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EMERGENTEndocrineICU
Diabetic Ketoacidosis (DKA)
Life-threatening metabolic emergency requiring early recognition, aggressive IV fluids, insulin infusion, and electrolyte replacement -with vigilant monitoring for complications.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Definition
DKA is characterized by the triad of hyperglycemia (usually BG > 250 mg/dL), anion-gap metabolic acidosis (pH < 7.3, bicarb < 18), and ketonemia/ketonuria. It results from absolute or relative insulin deficiency combined with excess counterregulatory hormones.
Why It Matters
⚠ Mortality up to 5% in adultsHigher in elderly, delayed recognition, or severe comorbidities. Cerebral edema is the leading cause of death in children.
Who Gets It
Type 1 DM (can be the presenting illness in ~25%)
Type 2 DM under physiologic stress
SGLT2-inhibitor users (euglycemic DKA -BG may be < 200!)
Insulin deficiency → unrestrained lipolysis → free fatty acids → hepatic ketogenesis (acetoacetate, β-hydroxybutyrate) → high anion gap metabolic acidosis. Hyperglycemia → osmotic diuresis → profound volume depletion and electrolyte losses. Total body K⁺ is depleted even when serum K⁺ appears normal or high (due to transcellular shift from acidosis).
Weakness, fatigue, altered mental status (in severe cases)
Timeline: hours to days (faster than HHS)
Exam
Kussmaul respirations (deep, rapid -compensating for acidosis)
Fruity/acetone breath
Signs of dehydration: dry mucosa, tachycardia, hypotension, poor skin turgor
Red Flags
Altered mental status → think cerebral edema, severe osmolarity
Potassium < 3.5 → do NOT start insulin until repleted
Euglycemic DKA (SGLT2i) -don't miss it
pH < 7.0 or bicarb < 10 → severe DKA, ICU threshold
Differential Diagnosis
HHS -BG often > 600, severe hypertonicity, no/minimal ketones, pH usually > 7.3
Alcoholic ketoacidosis -low or normal glucose, ketones present, history of binge drinking + poor PO
Starvation ketosis -mild, pH > 7.3, bicarb usually > 18
Other high AG acidosis -lactic acidosis, toxic ingestions (methanol, ethylene glycol, salicylates)
🧪 Workup & Diagnosis
Initial Workup
DO ALL OF THIS IMMEDIATELYThese tests diagnose DKA, guide fluid/insulin dosing, and identify precipitant -results change management NOW.
Labs (STAT)
BMP -BG, creatinine, K⁺, bicarbonate
VBG or ABG -pH, pCO₂, calculated bicarb
Anion gap = Na – (Cl + HCO₃) → normal 8–12; in DKA typically > 20
Beta-hydroxybutyrate (BHB), serum -≥ 3.0 mmol/L is diagnostic for DKA per ADA/EASD 2024. Preferred over urine ketones for both diagnosis AND monitoring resolution.
Urine ketones (only if serum BHB unavailable; moderate-to-large dipstick ketones is the fallback diagnostic threshold)
Phosphate, magnesium -often depleted
CBC, blood cultures -rule out infectious precipitant
Lipase -DKA can elevate lipase without true pancreatitis
HbA1c -assess chronic control
Urinalysis + urine culture
Pregnancy test (women of childbearing age)
Imaging / ECG
ECG -assess for hyperkalemia changes (peaked T waves, wide QRS) or ischemia as precipitant
CXR -rule out pneumonia as precipitant
CT head only if focal neuro deficits or concern for cerebral edema
Diagnostic Criteria for DKA UPDATED 2024
🔄 What changed in 2024 (ADA/EASD Consensus): Diagnosis now requires all three of the triad below, with BHB ≥ 3.0 mmol/L as the preferred ketone marker. Severity grading was simplified to pH and bicarb only, anion gap and mental status were removed (AG is confounded by hyperchloremic acidosis from NS; mental status is now used for ICU triage, not severity grading). Bicarb thresholds also shifted slightly.
Diagnostic Triad (all 3 required)
Hyperglycemia: glucose ≥ 200 mg/dL (or known diabetes; not required in euglycemic DKA on SGLT2i)
Ketosis: BHB ≥ 3.0 mmol/L (preferred) OR moderate-to-large urine ketones
CHANGED mild now 15–18 (was 15–18, but resolution threshold raised)
Anion gap and mental status were removed from severity grading in 2024. AG is still elevated in DKA but is confounded by hyperchloremic acidosis after NS resuscitation. Altered mental status remains an independent ICU-triage criterion.
ADA/EASD Consensus, 2024
🚨 Management
Treatment: Step by Step
BEFORE STARTING INSULINEnsure K⁺ ≥ 3.5 mEq/L. Starting insulin with hypokalemia causes fatal cardiac arrhythmia.
First 5 Minutes
Assess & Stabilize
ABCs. IV access × 2. Foley if altered or unable to void. Cardiac monitor. POC glucose. Draw all STAT labs. Call senior if severe (pH < 7.1, AMS, K⁺ < 3.5).
First 15–30 Minutes
IV Fluids -Bolus Only If Hemodynamically Unstable
• Unstable / severely volume-depleted:1-1.5 L isotonic crystalloid bolus over 1 hour (NS OR balanced).
• Stable:skip the bolus -start 250-500 mL/hr maintenance from the outset. The reflex "2 L for everyone" is out; over-resuscitation is the more common modern errorADA DKA Consensus, 2024
After the first hour, choose by corrected Na⁺ (calculator):
• Corrected Na ≤ 135 → continue 0.9% NS at 250-500 mL/hr
• Corrected Na > 135 → switch to 0.45% NaCl at 250-500 mL/hr
• If using LR: just continue LR throughout and skip the half-NS switch (LR's Na 130 already provides some free water; only switch to 0.45% NaCl if corrected Na > 150).
Goal: replace 3-6 L deficit over 24-48 h (gentler is fine; over-aggressive correction risks cerebral edema, especially in pediatrics -PECARN, 2018).
🔄 Updated Practice: Old teaching was NS (normal saline) for DKA fluid resuscitation. Newer evidence (SMART, 2018) suggests balanced crystalloids (LR) may be preferred -NS causes hyperchloremic metabolic acidosis, which can worsen and confuse the clinical picture. The 4 mEq/L of potassium in LR is NOT a contraindication in hyperkalemic DKA -it's below physiologic plasma K⁺, and NS paradoxically worsens hyperkalemia via hyperchloremic acidosis (shifts K⁺ out of cells). Balanced crystalloids are safe in DKA despite that potassium content, and avoid the hyperchloremic acidosis that saline adds on top of the ketoacidosis.
First Hour
Potassium Replacement
K⁺ < 3.5 → replace aggressively (20–40 mEq/hr IV), do NOT start insulin yet
K⁺ 3.5–5.0 → add 20–30 mEq K⁺ per liter of IVF, start insulin
K⁺ > 5.0 → start insulin, hold K⁺ replacement, recheck in 2 hours
Insulin Infusion
Regular insulin drip at 0.1 units/kg/hr fixed rate, no bolus required (per ADA/EASD Consensus, 2024). A 0.1 units/kg IV bolus is reserved for a delay in setting up the infusion. Target: BG drop of 50–75 mg/dL/hr.
🔄 Updated Practice: The old DKA protocol included an insulin IV bolus before starting the drip. Current guidance recommends NO routine bolus -start a fixed-rate continuous infusion at 0.1 units/kg/hr directly (a bolus is reserved for a delay in setting up the infusion). The bolus increased hypoglycemia risk without improving outcomes. Also: subcutaneous insulin protocols (insulin lispro/aspart q1-2h) are acceptable for mild-moderate DKA -IV is not always necessary.
When BG Hits 200–250 mg/dL
Switch to Dextrose-Containing Fluids
Add D5 to IV fluids (D5-0.45%NS) -reduce insulin drip to 0.05 units/kg/hr. Continue until anion gap closes, NOT just until BG normalizes. This is the most common resident mistake.
Resolution Criteria UPDATED 2024
Preferred (when BHB available):
Beta-hydroxybutyrate (BHB) < 0.6 mmol/L
AND patient tolerating PO / clinically improved
Alternative (BHB unavailable, ALL must be met):
Venous pH ≥ 7.3
Serum bicarbonate ≥ 18 mEq/L
Anion gap ≤ 10 mEq/L
ADA/EASD Consensus, 2024
🔄 What changed in 2024: BHB < 0.6 mmol/L is now the preferred resolution marker. Anion gap closure was a noisy endpoint, large-volume NS gives hyperchloremic acidosis, so the gap can stay wide even after ketones clear and patients get stuck on the drip. BHB measures the actual ketoacid driving DKA. Other changes: bicarb threshold raised from ≥ 15 to ≥ 18, the anion gap removed entirely as a criterion (it is retained only where ketone testing is unavailable), and glucose < 200 downgraded to a desirable extra (you can resolve DKA while still hyperglycemic, and euglycemic DKA exists).
Transitioning to Subcutaneous Insulin
Give SQ long-acting insulin 2 hours before stopping the drip (overlap is mandatory to prevent rebound ketoacidosis) ADA/EASD Consensus, 2024. Resume home insulin regimen if known, or start TDD calculation (0.5–0.8 units/kg/day). Ensure patient is eating and K⁺ > 3.5.
When to Escalate to ICU
pH < 7.0 or bicarb < 10
Altered mental status / decreased GCS
Hemodynamic instability not responding to fluids
K⁺ < 3.0 or > 6.0 with ECG changes
Concurrent MI, stroke, or surgical emergency
Swipe for more examples
📋 Case 1, DKA Insulin Drip Management
Patient: 28F with T1DM, glucose 520, pH 7.15, bicarb 8, AG 28, K⁺ 5.8
Time
Action
Hour 0
Start insulin drip 0.1 units/kg/hr fixed rate (no bolus). NS 1L/hr. Do NOT give K⁺ yet (K⁺ > 5.2).
Hour 2
Glucose 380 (↓140). K⁺ 4.5 → start KCl 20 mEq/hr in IV fluids. Continue insulin drip.
Hour 4
Glucose 280 (↓100/hr -on target). K⁺ 3.8 → increase KCl to 40 mEq/hr. AG closing (18).
Hour 6
Glucose 240 → approaching 250 threshold. Switch fluids to D5 1/2NS + KCl to prevent hypoglycemia while continuing insulin to clear the ketones (follow BHB, not the anion gap).
Key: Never stop insulin drip until: (1) BHB < 0.6 mmol/L (or if BHB unavailable, AG ≤ 10), (2) pH ≥ 7.3, (3) bicarb ≥ 18, (4) patient eating, AND (5) SC insulin given ≥ 2h prior.
📋 Case 2, Euglycemic DKA (SGLT2 Inhibitor)
Patient: 52F with T2DM on empagliflozin + metformin. Presents with nausea, vomiting, abdominal pain × 2 days. Glucose 185 (not elevated!). pH 7.18, bicarb 10, AG 24, ketones 5.2.
The trap: Glucose is near-normal → team almost missed DKA. SGLT2 inhibitors cause glycosuria → glucose stays low while ketoacidosis develops.
Treatment:
Stop empagliflozin immediately. Effects last 24–48h even after stopping.
Start D5NS + insulin drip, need dextrose from the start since glucose is already normal. Cannot let glucose drop further.
Aggressive K⁺ monitoring, same protocol as classic DKA.
Clear the ketones: Same endpoints, BHB < 0.6 mmol/L with pH > 7.3 or bicarb ≥ 18. Takes longer than classic DKA because you're limited by how fast you can run insulin with dextrose.
Key lesson: Always check a VBG/BMP on any patient on SGLT2i presenting with nausea/vomiting. Normal glucose does NOT rule out DKA. Check ketones and AG.
📋 Case 3, DKA with Severe Hypokalemia
Patient: 19M with T1DM, found unresponsive. Glucose 680, pH 6.95, bicarb 4, AG 36. K⁺ = 2.8.
Critical decision: K⁺ < 3.5 → DO NOT start insulin yet. Insulin drives K⁺ intracellular → can cause fatal arrhythmia.
Treatment:
Step 1: IV KCl 40 mEq/hr via central line (peripheral max 10 mEq/hr). Continuous telemetry. Recheck K⁺ every 1–2 hours.
Step 3: Once K⁺ > 3.5 → START insulin drip at 0.1 units/kg/hr. Continue K⁺ replacement aggressively.
Step 4: Consider bicarb ONLY if pH < 6.9 (give 100 mL of 8.4% NaHCO₃ in 400 mL sterile water over 2h). Controversial but ADA allows at pH < 6.9.
Key lesson: Always check K⁺ BEFORE starting insulin in DKA. K⁺ < 3.5 = replace first. This is the most dangerous moment in DKA management, insulin without adequate K⁺ kills.
💊 Medications & Doses
Medications & Dosing
Drug
Dose / Route
Indication
Key Points
Regular Insulin
0.1 units/kg/hr IV fixed-rate infusion, no bolus required ADA/EASD Consensus, 2024
Insulin infusion
Do not start if K⁺ < 3.5. Reduce to 0.05 when BG < 250
Normal Saline (0.9%)
1–1.5 L over 1 hr, then 250–500 mL/hr
Volume resuscitation. LR is an acceptable alternative (SMART, 2018 -balanced crystalloids reduce AKI/death vs NS in critically ill)
Switch to 0.45%NS after initial bolus based on corrected Na⁺
KCl
20–40 mEq/hr IV (max 40 mEq/hr via central line) 10–20 mEq/hr peripheral
Hypokalemia in DKA
Continuous cardiac monitoring. Expect K⁺ to drop as insulin given
Sodium Bicarbonate
100 mEq in 400 mL D5W over 2 hrs
pH < 6.9 only
Controversial. May worsen hypokalemia and CNS acidosis. Use sparingly
Phosphate
20–30 mmol IV over 6 hrs
PO₄ < 1.0 mg/dL with symptoms
Routine replacement not recommended. Risk of hypocalcemia
Glargine (Lantus)
0.25–0.3 units/kg SQ (or prior home dose)
Transition off drip
Give 2 hours before stopping drip. Do not skip
📋 On Rounds
Common Pimp Questions
Why should you NOT start insulin if K⁺ < 3.5?
Insulin drives K⁺ intracellularly. Starting insulin when K⁺ is already low can cause life-threatening hypokalemia and fatal cardiac arrhythmia. Always replete first.
When do you stop the insulin drip?
Per ADA/EASD 2024: BHB < 0.6 mmol/L AND patient eating. If BHB unavailable, use the fallback triad: pH ≥ 7.3, bicarb ≥ 18, AG ≤ 10. NOT just when glucose normalizes. And give long-acting SQ insulin 2 hours before stopping the drip to prevent rebound ketosis.
What is euglycemic DKA and who is at risk?
DKA occurring with near-normal glucose (< 200 mg/dL). Seen with SGLT2 inhibitors (empagliflozin, dapagliflozin, canagliflozin). They enhance renal glucose excretion, masking hyperglycemia while ketoacidosis progresses. Always check ketones in SGLT2i users with nausea/vomiting.
Why is bicarbonate therapy generally avoided in DKA?
Bicarb worsens hypokalemia, may cause paradoxical CNS acidosis (buffering acid generates CO₂, and that CO₂ diffuses across the blood-brain barrier into the CSF faster than the bicarbonate itself, so CSF pH paradoxically drops), and has not been shown to improve outcomes. Reserve for pH < 6.9 only.
Clinical Examples
📋 Case 1, Classic DKA with Insulin Omission
Patient: 24 y/o F with T1DM, ran out of insulin 3 days ago, presents with nausea, vomiting, abdominal pain, and Kussmaul breathing.
K⁺ 5.4 (>3.5), start regular insulin drip at 0.1 units/kg/hr fixed rate (no bolus)ADA/EASD Consensus, 2024
Add KCl 20 mEq/L to each liter of IVF (total body K⁺ depleted despite normal serum K⁺)
When BG < 250, add D5 to IVF and reduce insulin to 0.05 units/kg/hr
Teaching point: Serum K⁺ is artificially elevated due to acidosis-driven transcellular shift. Total body K⁺ is always depleted in DKA. Aggressively replete as insulin drives K⁺ intracellularly.
📋 Case 2, Euglycemic DKA on SGLT2 Inhibitor
Patient: 58 y/o M with T2DM on empagliflozin and metformin, presents with 2 days of nausea, vomiting, and fatigue after a GI illness.
Teaching point: SGLT2 inhibitors mask hyperglycemia by enhancing renal glucose excretion. Always check ketones in SGLT2i users presenting with nausea/vomiting, even if glucose is normal.
📋 Case 3, DKA with Severe Hypokalemia
Patient: 31 y/o F with T1DM, presenting with DKA triggered by UTI. Found altered in the ED.
Key findings: BG 520, pH 7.08, bicarb 5, AG 30, K⁺ 2.9, ECG shows U waves and prolonged QTc.
Management:
DO NOT start insulin, K⁺ < 3.5 is an absolute contraindication
Aggressive K⁺ repletion: KCl 40 mEq/hr IV via central line with continuous telemetry
Start insulin ONLY when K⁺ ≥ 3.5 (recheck q1h during repletion)
Treat UTI precipitant with appropriate antibiotics
Teaching point: Insulin before K⁺ repletion in hypokalemic DKA causes fatal arrhythmias. This is the single most important safety rule in DKA management.
What to Say on Rounds
📋 Sample Presentation
"Mr. Smith is a 32-year-old with Type 1 DM presenting with a 2-day history of nausea, vomiting, and abdominal pain in the setting of missed insulin doses. He was found to have a glucose of 420, pH 7.18, bicarb of 10, and an anion gap of 24, consistent with severe DKA. He was started on NS resuscitation and a regular insulin drip at 0.1 units/kg/hr after K⁺ was confirmed to be 3.8. Over the past 8 hours, his glucose has come down to 240, his BHB has fallen from 5.2 to 1.4, and his bicarb is now 16. We are targeting a BHB below 0.6 with a pH above 7.3 before transitioning to subcutaneous insulin, rather than following the anion gap, which stays open with saline-induced hyperchloremic acidosis. His precipitant appears to be medication non-adherence, and we are involving diabetes education."
Monitoring Schedule
During Active DKA
Glucose: every 1 hour (via POC meter)
BMP (or at least K⁺, bicarb): every 2–4 hours
Anion gap: calculated every 2–4 hours to confirm closure
Beta-hydroxybutyrate: every 4 hours (preferred over urine ketones)
Urine output: target ≥ 0.5 mL/kg/hr -place Foley if needed
ECG: if K⁺ < 3.0 or > 6.0
Pitfalls to Watch
Stopping insulin too early -always wait for AG closure, not just BG normalization
Forgetting the 2-hour overlap when transitioning to SQ insulin
Overcorrecting fluids -iatrogenic fluid overload, especially in elderly or cardiac patients
Missing the precipitant -always ask: why did they get DKA?
Euglycemic DKA on SGLT2i -BG may be near-normal; check ketones regardless
Cerebral edema -rare in adults but watch for headache, declining GCS during treatment
All three are required: hyperglycemia (or a known diabetes diagnosis), ketosis, and metabolic acidosis.Beta-hydroxybutyrate 3.0 mmol/L or above is the preferred ketone marker, not urine ketones, which measure acetoacetate and can look falsely reassuring early and falsely persistent late. Severity is now graded on pH and bicarbonate only; anion gap and mental status were dropped.
Fluids First
Isotonic crystalloid 1 to 1.5 L in the first hour, then 250 to 500 mL/h, switching to half-normal saline if the corrected sodium is high. Balanced crystalloid is preferred over normal saline, which causes a hyperchloremic acidosis that keeps the bicarbonate low after the ketosis has cleared and makes the patient look untreated. Restoring perfusion alone lowers the glucose substantially.
Check Potassium Before Insulin, Every Time
Ensure potassium is at least 3.5 mEq/L before starting insulin.Total body potassium is depleted even when the serum level is normal or high, because acidosis and insulin deficiency drive it out of cells. Insulin given into hypokalemia causes fatal arrhythmia. Add 20 to 40 mEq per liter once the level is below 5.3 and the patient is making urine.
Insulin Infusion Without a Bolus
Regular insulin 0.1 units/kg/h. Target a glucose fall of 50 to 75 mg/dL/h. Add dextrose once the glucose reaches about 200 and continue the insulin, because the target is closing the anion gap, not normalizing the glucose. Stopping insulin at a normal glucose leaves the ketosis running.
Track the Gap, Not the Sugar
Resolution is a closed anion gap with a bicarbonate above 15 to 18 and a beta-hydroxybutyrate below 0.6, not simply a normal glucose. Urine ketones stay positive after resolution, because acetoacetate rises as beta-hydroxybutyrate is metabolized, so following them causes unnecessarily prolonged treatment.
Overlap the Transition Off the Drip
Give subcutaneous basal insulin 2 to 4 h before stopping the infusion.IV insulin has a half-life of minutes, so stopping it cleanly puts a type 1 patient straight back into ketoacidosis. The patient must also be eating and the gap closed before the drip comes down.
Hunt the Precipitant: the 5 I's
Infection (30 to 40%, the commonest, from urine, chest or skin), Insulin missed or under-dosed, Infarction (MI, stroke, mesenteric ischemia), Intoxication, Inflammation (pancreatitis). Fever is often absent, so a normal temperature does not exclude sepsis, and a troponin and ECG are worth doing in the older patient.
Two Things Not to Do, and One Not to Miss
Do not give bicarbonate except at a pH below about 6.9: it worsens intracellular acidosis, delays ketone clearance and causes hypokalemia. Do not give routine phosphate unless it is severely low or there is cardiac or respiratory compromise. Do not miss euglycemic DKA in SGLT2 inhibitor users, where the glucose can be below 200; an anion-gap acidosis with ketones in an acutely ill patient on one of these drugs is DKA until proven otherwise, treated with insulin plus dextrose. Cerebral edema is the leading cause of death in children, which is why fluid is given more cautiously in pediatrics.
RoundsRx Infographic Series · #12 · Renal & Metabolic · PDF 162 KB
Text version
ICU / Endocrine · One Pager
Diabetic Ketoacidosis
Hyperglycemia + ketosis + acidosis. Fluids first. Check K⁺ before insulin. Clear the ketones (BHB), not just the glucose.
🧪 Diagnosis
BG ≥ 200 mg/dL or known diabetes
pH < 7.3 and/or Bicarb < 18
BHB ≥ 3.0 mmol/L (or urine ketones 2+)
Anion gap NOT a criterion (ADA/EASD 2024)
Euglycemic DKA: BG normal on SGLT2i
⚡ Precipitants
Infection (30–40%)
Missed insulin (20–25%)
New diagnosis T1DM
MI, pancreatitis, surgery
SGLT2 inhibitor use
🚨 Management -Step by Step
1
IV fluids: isotonic saline or balanced crystalloid 500–1000 mL/hr × 2–4h. Balanced crystalloid preferred where available (faster resolution, less hyperchloremic acidosis)
2
Check K⁺ BEFORE insulin -if < 3.5, replace first. Do NOT start insulin.
3
Insulin: fixed-rate infusion 0.1 units/kg/hr IV, a bolus is not required. HHS: 0.05 units/kg/hr. Mild DKA may use SQ rapid-acting analogue ADA/EASD 2024
4
When BG < 250: Add D5 to IVF, reduce insulin to 0.05 units/kg/hr
5
Resolved when: BHB < 0.6 mmol/L AND (pH ≥ 7.3 or bicarb ≥ 18); ideally BG < 200. Do NOT use the anion gap or urine ketones
6
SQ insulin overlap: Give basal insulin 1–2h before stopping drip, once eating
ADA/EASD 2024: BHB replaces the anion gap for diagnosis and resolution
Resolution: BHB < 0.6; hyperchloremic acidosis from saline keeps the gap open
Bicarb: Only if pH < 7.0 (not routine)
ICUCriticalCommon
Sepsis & Septic Shock
Life-threatening organ dysfunction from infection. Every hour of antibiotic delay = ~7% more mortality. Diagnose fast, culture fast, treat fast. Source control is as important as antibiotics.
🔍 Overview
Sepsis-3 Definitions (Singer, JAMA 2016)
Sepsis: Life-threatening organ dysfunction caused by a dysregulated host response to infection. Operationally defined as SOFA score increase ≥ 2 from baseline in a patient with suspected infection.
qSOFA (bedside screen -1 point each): Altered mentation (GCS < 15) | RR ≥ 22 | SBP ≤ 100. Score ≥ 2 = high risk → triggers full SOFA + ICU evaluation. qSOFA is a screen, NOT a definition. ⚠️ SSC 2026: qSOFA has poor sensitivity -misses too many septic patients. NEWS/MEWS now recommended as primary screening tools.
SIRS Criteria (historical -Bone, Chest 1992): Infection + ≥ 2 of: Temp > 38°C or < 36°C | HR > 90 | RR > 20 or PaCO₂ < 32 | WBC > 12,000 or < 4,000 or > 10% bands. Replaced by Sepsis-3 (2016) due to poor specificity -SIRS is present in most hospitalized patients Sepsis-3, 2016 regardless of infection. Still used as a triage trigger in some institutions given its high sensitivity.
🔴 SSC 2026 Guidelines (March 2026) -Key Changes from 2021:
Domain
2021 SSC
2026 SSC Update
Screening
qSOFA suggested outside ICU
NEWS/NEWS2/MEWS/SIRS now recommended OVER qSOFA. qSOFA has poor sensitivity -should not be sole screening tool.
Fluids
30 mL/kg crystalloid within 3h. Balanced crystalloids already suggested over 0.9% saline (weak rec, low-quality evidence; it was the 2016 edition that had no preference).
30 mL/kg still suggested, with greater emphasis on individualizing fluid after that initial bolus (liberal or restrictive, per patient and system factors). Balanced-over-saline unchanged from 2021. New: fluid removal after resuscitation now addressed.
Vasopressors
Start via central line. NE first-line (strong).
Peripheral vasopressor start now OK -don't delay for central access. NE first-line is still a strong "recommend" against dopamine, epinephrine and selepressin; only the comparison against vasopressin or angiotensin II is a conditional "suggest", so this is not a blanket downgrade. New: MAP 60-65 for adults ≥ 65 years.
Steroids
Suggested if ongoing vasopressor need (reversed 2016 stance against routine steroids)
Maintained from 2021. Hydrocortisone 200 mg/day for septic shock with ongoing vasopressor requirement. No specific wait time mandated (trial enrollment used ≥ 4h).
Antibiotics
Within 1h of recognition
Refined: 1 hour for septic shock, 3 hours for sepsis without shock. New: antibiotic optimization & prehospital antibiotics may reduce mortality (OR 0.58).
Beta-lactam dosing
Not addressed
Recommend (strong) prolonged infusion of beta-lactams for maintenance after loading dose. Improves time-dependent killing.
Anaerobic coverage
Routine empiric pip-tazo / metronidazole as part of broad-spectrum cover
Stop reflexively adding anaerobic coverage.Chanderraj, 2024 showed empiric anti-anaerobic agents in critically ill patients without an anaerobic source ↑ mortality, C. diff, and VRE. New default empiric: Vanc + Cefepime. Add Zosyn / metronidazole only for clear anaerobic sources (intra-abdominal, aspiration w/ abscess, nec fasc, pelvic, bite wound).
Variable. CNS: S. pneumoniae, N. meningitidis, Listeria (elderly/immunocompromised). Endocarditis: S. aureus, viridans strep, enterococci. Consider early in sepsis with no clear source, especially with fever + AMS or new murmur
Source control is as important as antibiotics. SSC 2026 emphasizes anatomic source control (drain abscesses, remove infected lines, debride necrotic tissue, decompress obstructed urinary tract) within 6–12 hours of recognition. Antibiotics alone fail without source control.
Hypotension, warm/flushed skin (early distributive), later cold/mottled
Altered mental status (confusion, agitation, lethargy)
Decreased urine output (< 0.5 mL/kg/hr)
Elevated lactate (tissue hypoperfusion marker)
Don't Be Fooled: Elderly, immunocompromised (transplant, chemotherapy), and patients on chronic steroids may present with NO fever, minimal leukocytosis, and normal HR. Hypothermia and leukopenia in sepsis = very bad prognostic signs. Think sepsis in any elderly patient with AMS + unexplained hypotension.
🧪 Workup & Diagnosis
Sepsis Bundle SSC, 2026
Septic shock: ALL within 1 hour. Sepsis without shock: antibiotics within 3 hours.(SSC 2026 now distinguishes timing by severity -previously 1h for all sepsis.)
Measure serum lactate (repeat if initial > 2 mmol/L to confirm clearance)
Blood cultures × 2 sets from 2 separate sites -before antibiotics, but do not delay antibiotics > 45 min waiting for cultures
Broad-spectrum antibiotics administered IV, 1h for septic shock, 3h for sepsis without shock (SSC 2026)
30 mL/kg balanced crystalloid (LR or PlasmaLyte) bolus if MAP < 65 mmHg OR lactate ≥ 4 mmol/L (SSC 2026 suggests balanced over 0.9% saline, except TBI)
CT abdomen/pelvis with contrast -abdominal source, abscess (do not delay abx for CT)
CT head -if AMS, meningismus, focal neuro deficit (LP after if no mass lesion)
Lactate Interpretation
Lactate Level
Category
Action
< 2 mmol/L
Normal
Standard care; monitor if clinical concern
2–4 mmol/L
Elevated -sepsis
Aggressive resuscitation; repeat lactate in 2h
≥ 4 mmol/L
Cryptic shock
Mandatory aggressive resuscitation: 30 mL/kg balanced crystalloid, ICU evaluation, source control, repeat lactate q2h. Vasopressors if MAP < 65 after fluids (per SSC 2026, not all cryptic shock requires immediate pressors if BP responds).
Lactate Clearance: Target ≥ 10% clearance per 2 hours. Failure to clear lactate despite resuscitation = inadequate source control, occult bleeding, or mitochondrial dysfunction. Persistently elevated lactate = very poor prognosis.
🚨 Management
▶ How to Escalate Sepsis Care, Step by Step (tap to expand)
The SSC 2026 paradigm: recognize fast, antibiotics fast (within 1 hour of recognition in shock), source control fast, and de-resuscitate once stable. Each hour of antibiotic delay in septic shock raises mortality ~7%. The bundle is not a checklist for documentation, it's a survival curve.
Defines the "Hour-1 bundle" trigger. Mortality jumps from ~10% (sepsis) to ~40% (shock); the bundle window is when survival is shaped.
Bedside screen
qSOFA ≥ 2 (RR ≥ 22, AMS, SBP ≤ 100) or NEWS2 ≥ 5 at floor/ED
qSOFA is a screening trigger, not a diagnosis. A "0" qSOFA in a sick-looking patient still gets the workup, clinical gestalt overrides scores.
Step 2: Hour-1 bundle (the survival window)
Action
How
Why
Lactate
VBG or specific lactate. Recheck in 2 hr.
Initial lactate stratifies severity; clearance > 10% per 2 hr is the resuscitation goal. Persistent lactate > 4 is high-mortality.
Cultures BEFORE antibiotics
2 blood cultures from separate sites; site-specific (UA, sputum, CSF, peritoneal) as indicated. Don't delay antibiotics > 45 min for cultures.
Pretreatment cultures double yield. But never sacrifice antibiotic timing in shock, get what you can in < 45 min and move on.
Antibiotics within 1 hr (shock) or 3 hr (sepsis without shock)
Default empiric: vancomycin + cefepime. Tailor to source (see Step 3).
The move off pip-tazo as universal default is driven by Chanderraj (2024): unnecessary anti-anaerobic coverage strips protective gut anaerobes and is associated with higher mortality, C. diff and VRE. Cefepime + vanc is broad without that anaerobic hit. Note what ACORN did NOT show: its primary AKI/death endpoint was a wash, so "avoid pip-tazo to protect the kidneys" is not the reason.
Balanced crystalloid 30 mL/kg
LR or PlasmaLyte (not NS) over 1-3 hr if MAP < 65 or lactate ≥ 4. Re-assess after each 500 mL (passive leg raise, lung auscultation, JVP).
SMART (2018): balanced fluids reduce major adverse kidney events vs NS. CLOVERS (2023): liberal vs restrictive fluid showed no benefit, don't reflex more if not responding. NS only in TBI.
Start pressors early
Norepinephrine 0.01-0.05 mcg/kg/min, titrate to MAP ≥ 65. Peripheral start is OK while central line is being placed, don't delay.
SSC 2026: peripheral pressors safe for short-term use, removing the "central access first" delay. Waiting for central line costs survival minutes.
Step 3: Choose empiric antibiotic by suspected source
Intra-abdominal, aspiration with abscess/empyema, nec fasc, pelvic, bite
Vancomycin + piperacillin-tazobactam, OR vanc + cefepime + metronidazole
Anaerobic coverage essential. Use pip-tazo despite AKI signal when the anaerobic indication is clear.
Pneumonia, severe community-acquired
Ceftriaxone + azithromycin (typical CAP), or vanc + cefepime if HAP/VAP risk
Macrolide for atypicals (Legionella, Mycoplasma). Add vanc if MRSA risk (post-influenza, cavitary, IVDU).
Urinary
Ceftriaxone (uncomplicated) or pip-tazo/cefepime (complicated, obstruction, hospital exposure)
~70% E. coli, others Klebsiella, Pseudomonas. Add vanc only if hardware (stent, catheter) or known prior MRSA.
Meningitis
Ceftriaxone 2 g IV + vancomycin + dexamethasone (give before/with antibiotics in pneumococcal) + ampicillin (Listeria) if > 50 yr, immunocompromised, alcoholic, pregnant
Dexamethasone reduces mortality and neurologic sequelae in pneumococcal meningitis only when given before/with the first antibiotic dose (de Gans, 2002).
Neutropenic fever
Cefepime monotherapy (or pip-tazo). Add vanc only if hemodynamic instability, line infection, severe mucositis, MRSA history.
Routine empiric vanc no longer recommended (IDSA 2018, 2024 update); doesn't improve outcomes and selects resistance.
Time to source control should be < 6-12 hr for drainable infections. Persistent shock despite adequate antibiotics + fluids + pressors = look for missing source control.
Step 5: Refractory shock → escalate
Trigger
Do This
Why
NE ≥ 0.25-0.5 mcg/kg/min still not at MAP 65
Add vasopressin 0.03 U/min fixed dose
VASST (2008): vasopressin spares NE; mortality signal in less-severe shock subgroup. Fixed dose, no titration.
Persistent shock on NE + vasopressin
Add epinephrine; consider hydrocortisone 200 mg/day IV (50 mg q6h or continuous)
Persistent lactate after MAP and pressors are optimized usually means undrained source or wrong antibiotic.
Step 6: ICU supportive bundle
Element
Target
Why
Lung-protective ventilation
TV 6 mL/kg PBW, Pplat ≤ 30, target SpO₂ 92-96%
ARDSNet (2000): TV 6 vs 12 mL/kg reduced mortality 22%. Applies to all ICU mechanical ventilation.
Glucose
140-180 mg/dL
NICE-SUGAR (2009): tight control (81-108) increased mortality and 13× severe hypoglycemia.
DVT prophylaxis
Enoxaparin (UFH if CrCl < 30) + SCDs
Septic patients have high VTE risk.
Stress ulcer prophylaxis
PPI or H2-blocker IF mechanical ventilation > 48 hr, coagulopathy, prior GI bleed, TBI, large burns. Not universally.
SUP-ICU (2018): routine prophylaxis no mortality benefit; weigh C. diff and pneumonia risk.
Enteral nutrition
Within 24-48 hr
Preserves gut mucosal integrity. NUTRIREA-2 and CALORIES showed enteral and parenteral mortality similar but enteral has fewer complications.
Transfusion threshold
Hgb < 7 (or < 8 if active cardiac ischemia)
TRICC (1999): restrictive (< 7) non-inferior to liberal (< 10).
Step 7: De-escalate at 48-72 hours
Reassess everything at 48-72 hr:
Narrow antibiotics to culture-directed therapy (e.g., vanc → cefazolin if MSSA; cefepime → ceftriaxone if susceptible).
Stop empiric MRSA coverage if cultures negative at 48 hr and no MRSA risk factors.
Total duration 5-7 days for most sepsis with good source control and clinical improvement (PRORATA, SAPS, BALANCE). Longer for endocarditis, osteo, undrained abscess, S. aureus bacteremia.
Procalcitonin can guide stopping (PRORATA: 2.7 day reduction, no mortality penalty).
De-resuscitate: once stable and MAP supported off pressors, start net-negative fluid balance. SSC 2026 explicitly added this. Fluid overload at day 3-5 worsens mortality.
Shortcuts that override the ladder
Scenario
Do This
Why
Severe penicillin allergy (anaphylaxis, SJS/TEN)
Aztreonam + vanc + metronidazole for broad coverage; meropenem if SJS to non-PCN beta-lactam
Cefepime is generally safe with non-severe PCN allergy (cross-reactivity ~1-3%), but in severe IgE/SJS history, aztreonam (monobactam) avoids cross-reactivity.
Renal failure / on dialysis
Use AUC-guided vancomycin dosing and adjust all renally-cleared drugs
Vanc and beta-lactams need renal dose adjustment. Older observational data suggested pip-tazo + vanc raises AKI rate, but the ACORN RCT (2023) did not confirm it, so do not withhold pip-tazo on that basis alone. Cefepime carries its own risk here: neurotoxicity accumulates in renal failure, so it needs renal dose reduction.
Standard category labels for these. Treat aggressively; sepsis in pregnancy carries high maternal-fetal mortality.
Sepsis-induced cardiomyopathy (drop in EF, cold extremities, low CO despite MAP)
Add dobutamine 2-20 mcg/kg/min while continuing NE
Septic cardiomyopathy is reversible, lasts days to weeks. Echo confirms; dobutamine supports CO until myocardium recovers.
Suspected adrenal crisis (hyponatremia, hyperkalemia, eosinophilia, on chronic steroids)
Empiric hydrocortisone 100 mg IV q8h upfront, before cosyntropin if life-threatening
Sepsis can precipitate adrenal crisis in chronic steroid users or unrecognized Addison. Stress-dose covers both relative adrenal insufficiency and sepsis itself.
Influenza or COVID superinfection suspected
Oseltamivir 75 mg BID or remdesivir/dexamethasone per current protocol; cover MRSA (post-influenza necrotizing pneumonia) and Strep pneumo
Post-influenza bacterial superinfection is classically MRSA (necrotizing) or pneumococcus. Don't withhold antiviral while bacterial workup pending.
Septic shock in patients with poor baseline functional status has > 80% mortality. Aggressive ICU care without alignment to goals worsens dying.
Resuscitation Strategy
0–15 min -Recognition & Stabilization
ABCs. Two large-bore IVs. Cardiac monitor. O₂. Call for help.
If shock criteria met (MAP < 65, lactate ≥ 4, AMS): activate ICU consult now -not after labs, not after imaging.
Bedside echo to exclude obstructive shock (PE, tamponade) and assess LV function.
0–30 min -Cultures then Antibiotics (in that order, fast)
Blood cultures × 2 → broad-spectrum antibiotics within 1 hour. Every hour of delay in septic shock increases mortality ~7%. Narrow based on culture results at 48–72h.
Drug
Dose
Bugs Covered
⚠️ Side Effects
When to Use
Piperacillin-tazobactam (Zosyn)
3.375g IV q6h (or 4.5g q8h extended infusion over 4h)
⚠️ AKI risk when paired with vancomycin is not confirmed (observational signal only; the ACORN RCT was neutral) ACORN, 2023 (use cefepime + vanc as default empiric unless anaerobic source). C. diff (higher than cefepime, broad anaerobic kill). Hypokalemia (common, often missed, check daily BMP; mechanism = non-reabsorbable anion in distal tubule). Thrombocytopenia & neutropenia with courses > 7–14 days. Rash; DRESS (rare); cross-reactivity with severe PCN allergy. Transaminitis; cholestasis with prolonged infusion. False-positive serum galactomannan (critical in heme/onc aspergillus screening). Drug fever. Seizures in renal failure (rare). Diarrhea (non-C. diff).
Reserve for clear anaerobic source (intra-abdominal, aspiration w/ abscess, nec fasc, pelvic, bite wound). No longer the default empiric in 2026, Chanderraj, 2024 showed empiric anti-anaerobic agents without an anaerobic indication ↑ mortality, C. diff, and VRE.
Cefepime (Maxipime)
2g IV q8h
Gram-positives: Strep, MSSA (not MRSA) Gram-negatives: E. coli, Klebsiella, Pseudomonas, Enterobacter, Serratia, Citrobacter No anaerobes
⚠️ Cefepime-induced neurotoxicity (CIN), encephalopathy, confusion, myoclonus, asterixis, tremor, non-convulsive status epilepticus. Esp. renal failure, elderly, sepsis. Often misdiagnosed as ICU delirium; EEG shows triphasic waves or generalized periodic discharges. Resolves with discontinuation ± HD. Dose-adjust aggressively for CrCl. Overt seizures (part of spectrum). C. diff. Rash; hypersensitivity (PCN cross-reactivity ~1–3%, safe in non-severe PCN allergy). Thrombocytopenia, eosinophilia, positive Coombs (rare AIHA). Transaminitis. Drug fever; infusion-site phlebitis. Candidiasis / thrush with prolonged use.
New 2026 default empiric (paired with vanc). Covers Pseudomonas + GNR without anaerobic spectrum. ↓ AKI vs pip-tazo+vanc. Add metronidazole only if a true anaerobic source is identified.
⚠️ Seizures (esp. renal failure, CNS lesion, elderly, high dose, lower risk than imipenem; always dose-adjust for CrCl). ↓ valproic acid 50–90% in 24–48h → breakthrough seizures/status epilepticus (AVOID combo, dose-escalating VPA does NOT rescue; bridge to levetiracetam). C. diff, diarrhea, nausea. Rash / hypersensitivity (PCN cross-reactivity ~1%, safe in non-severe PCN allergy). Thrombocytosis, eosinophilia, positive Coombs (rare AIHA); transaminitis. VRE + Candida superinfection with prolonged courses. Encephalopathy/myoclonus in renal failure.
Use if: prior ESBL/MDR organism, recent hospitalization + IV abx within 90 days, high local resistance, failed pip-tazo. Broadest gram-negative coverage.
Vancomycin (Vancocin)
15–20 mg/kg IV q8–12h (AUC/MIC target 400–600)
Gram-positives only:MRSA, MSSA, Strep, Enterococcus (not VRE) No gram-negatives. No anaerobes.
⚠️ Nephrotoxicity / AKI (dose- and duration-dependent; the long-assumed extra hit from pairing with pip-tazo was not confirmed by RCT ACORN, 2023; AUC/MIC 400–600 guided dosing ↓ risk vs trough-only). Vancomycin flushing syndrome (formerly "Red Man", histamine release, NOT IgE allergy; infuse over ≥ 1h, pre-treat with antihistamine if recurrent). Ototoxicity (dose/duration; additive with loops + aminoglycosides). DRESS, SJS/TEN (rare). Linear IgA bullous dermatosis. Neutropenia + thrombocytopenia with courses > 7–14 days. Drug fever. Phlebitis, prefer central line for prolonged courses.
Add for MRSA coverage -any sepsis with: prior MRSA, IVDU, skin/soft tissue source, healthcare exposure, HD catheter. Pair with pip-tazo, cefepime, or meropenem.
Linezolid (Zyvox)
600 mg IV/PO q12h
Gram-positives only:MRSA, VRE, Strep, Enterococcus No gram-negatives. No anaerobes.
⚠️ Thrombocytopenia (courses > 7–14d, monitor CBC weekly; most common dose-limiting toxicity). Serotonin syndrome (weak reversible MAOi, avoid SSRIs, SNRIs, tramadol, meperidine, TCAs; ideally 2-week washout. Classic inpatient pimp trap). Peripheral neuropathy + optic neuritis (courses > 28d, may be irreversible; discontinue at first sign). Myelosuppression / pancytopenia (marrow suppression, > 14d). Lactic acidosis (mitochondrial protein synthesis inhibition, prolonged use, often > 28d). Tyramine reaction (avoid aged cheese, cured meats, wine, MAOi effect). Hypoglycemia in diabetics on sulfonylureas/insulin. Headache, nausea, diarrhea, rash.
Alternative to vanc if: CKD/AKI (no renal adjustment), VRE suspected, MRSA pneumonia (superior lung penetration), no IV access (100% PO bioavailability).
⚠️ Disulfiram-like reaction with alcohol (flushing, tachycardia, nausea, vomiting, counsel: NO alcohol during + 72h after. Applies to mouthwash, cough syrup, IV meds in propylene glycol). Peripheral neuropathy (dose- and duration-related, distal axonal, courses > 4–6 weeks; may be irreversible). CNS toxicity, encephalopathy, cerebellar syndrome (ataxia, dysarthria, nystagmus), seizures. MRI: symmetric cerebellar dentate / corpus callosum splenium lesions; reversible with discontinuation. Metallic taste + nausea (very common, adherence issue). Warfarin INR ↑ (CYP2C9 inhibition, recheck INR at 48–72h; anticipate dose reduction). Lithium toxicity. Reversible leukopenia. Optic neuropathy (rare). Aseptic meningitis (very rare).
Add to cefepime or meropenem when anaerobic coverage needed (intra-abdominal, abscess, aspiration with empyema). Not needed with pip-tazo (already covers anaerobes).
Key principle (2026): Default empiric is Vanc + Cefepime, covers MRSA + Pseudomonas + GNR without unnecessary anaerobic spectrum. Add Zosyn or metronidazole only when there's a clear anaerobic source (intra-abdominal, aspiration w/ abscess/empyema, nec fasc, pelvic, bite wound).
Fluid Resuscitation
30 mL/kg balanced crystalloid (LR or PlasmaLyte preferred over NS)SMART, 2018SALT-ED, 2018 if MAP < 65 or lactate ≥ 4. Early aggressive resuscitation is key Rivers EGDT, 2001 -though the specific EGDT protocol (CVP, ScvO2 targets) was later shown unnecessary by ProCESS, 2014.
After initial bolus: reassess after each 500 mL. Check JVP, lung auscultation, passive leg raise response. Do not reflexively give more fluids if no hemodynamic response -start vasopressors. Fluid overload in sepsis = worse outcomes. CLOVERS, 2023 showed no benefit to liberal fluid strategy, supporting a conservative approach. Use crystalloids over colloids -CRISTAL, 2013 found no 28-day mortality difference between colloids and crystalloids. Notably, FEAST, 2011 demonstrated that fluid boluses increased mortality in febrile children (resource-limited setting), underscoring the importance of judicious fluid use.
🔄 Updated Practice (SSC 2026): Balanced crystalloids (LR/PlasmaLyte) now suggested over 0.9% saline (except TBI -use NS). 30 mL/kg remains suggested but with greater emphasis on individualization. CLOVERS, 2023 showed no difference between restrictive (~1.8L) and liberal (~3.8L) strategies. New in 2026: fluid removal after resuscitation is now addressed -de-resuscitate once stabilized. Fluid overload kills -reassess after each bolus.
Vasopressors -MAP Target ≥ 65
Norepinephrine first-line (start 0.01–0.05 mcg/kg/min, titrate to max ~3 mcg/kg/min)SOAP II, 2010 -α₁ > β₁, increases MAP without excessive HR.
Add vasopressin 0.03 units/min (fixed dose, no titration) when NE reaches 0.25–0.5 mcg/kg/min (spares NE, possibly reduces mortality) VASST 2008.
Add epinephrine for refractory shock. Use dobutamine (2–20 mcg/kg/min) only if MAP adequate but persistent signs of low CO (cold extremities, rising lactate, low ScvO₂). Hydrocortisone 200 mg/day IV (50 mg q6h or continuous) for septic shock with ongoing vasopressor requirement (SSC 2021/2026 -conditional recommendation). Shortens shock duration. ADRENAL 2018; APROCCHSS 2018CORTICUS, 2008.
🔄 Updated Practice (SSC 2026):Peripheral vasopressor start is now OK -don't delay pressors waiting for central access. Norepinephrine remains first-line but downgraded from "recommend" to "suggest" (still first-line, weaker strength). Vasopressin second-line (0.03 units/min, fixed). Dopamine and "renal-dose dopamine" are DEBUNKED. New in 2026: for adults ≥ 65, suggest initial MAP 60-65 mmHg over higher targets. Prolonged beta-lactam infusion now recommended (strong) for maintenance dosing after loading dose.
Source Control
Identify and eliminate the source of infection -as important as antibiotics.
Drain abscess (IR-guided or surgical). Remove infected IV lines (replace in new site). Decompress biliary obstruction (ERCP or percutaneous). Surgical consult for perforated viscus, necrotizing fasciitis, infected prosthetic. Time to source control should be < 6–12 hours for drainage procedures.
ICU-Level Bundles
Ventilation: Lung-protective if intubated (TV 6 mL/kg PBW, Pplat ≤ 30). Glucose: Target 140–180 mg/dL with insulin infusion NICE-SUGAR, 2009. Avoid hypoglycemia. DVT prophylaxis: Enoxaparin (or UFH if CrCl < 30) + SCDs. Stress ulcer prophylaxis: IV PPI or H2-blocker if high-risk (mechanically ventilated > 48h, coagulopathy, history of GI bleed, TBI, burns > 35% BSA). Not all ICU patients need it -SUP-ICU, 2018: no mortality benefit from routine prophylaxis; weigh risk of C. difficile and nosocomial pneumonia. Nutrition: Early enteral nutrition within 24–48h. Enteral is preferred over parenteral -NUTRIREA-2, 2018 and CALORIES, 2014 showed no mortality difference between parenteral and enteral, but enteral maintains gut integrity. Antibiotic de-escalation: Reassess at 48–72h based on cultures + clinical trajectory. Target 5–7 days total if good source control and clinical improvement. Use procalcitonin to guide stopping PRORATA 2010.
Resuscitation Targets
Parameter
Target
Notes
MAP
≥ 65 mmHg (60-65 if age ≥ 65)
Higher (≥ 75) in chronic hypertension or AKI. SSC 2026: lower target 60-65 for older adults spares vasopressor exposure.
Lactate
Clearance ≥ 10% per 2h
Target < 2 mmol/L; failure to clear = reassess
UOP
≥ 0.5 mL/kg/hr
Oliguria = inadequate perfusion or AKI
ScvO₂
≥ 70%
Low = high O₂ extraction → low CO or anemia
Glucose
140–180 mg/dL
Avoid hypoglycemia -check q1–2h
Hgb
≥ 7–9 g/dL
Transfuse if Hgb < 7 (or < 8 if cardiac ischemia) TRICC, 1999
💊 Medications & Doses
Empiric Antibiotic Selection
🔄 SSC 2026 + Chanderraj, 2024, pick empiric by source, not by reflex. Two principles drive every choice below:
No anaerobic source → no anti-anaerobic agent. Routine empiric pip-tazo, metronidazole, or clindamycin in critically ill patients without an anaerobic indication is associated with higher mortality, C. difficile, and VRE. Chanderraj, 2024
Clinical Scenario
Empiric Regimen
Notes
Sepsis, no clear source (default while workup pending)
Cefepime (Maxipime) 2g IV q8h (Pseudomonas, E. coli, Klebsiella, Enterobacter, MSSA) + Vancomycin (Vancocin) 25–30 mg/kg loading (MRSA, Strep, Enterococcus)
New 2026 default. Covers MRSA + Pseudomonas + GNR without unnecessary anaerobic coverage. Use this instead of Vanc + Zosyn unless an anaerobic source is identified.
CAP (community-acquired pneumonia) Pulmonary source = ~40–50% of sepsis
Typical organisms (S. pneumoniae, H. influenzae) + atypicals (Mycoplasma, Legionella). Add vanc if MRSA risk (post-influenza, cavitary, prior MRSA). Levofloxacin monotherapy is an alternative.
Severe CAP + sepsis / HAP / VAP
Cefepime (Maxipime) 2g IV q8h + Vancomycin (Vancocin)
Pseudomonas + MRSA coverage. Cefepime preferred over Zosyn (2026), pneumonia is not an anaerobic source unless aspiration with abscess or empyema.
Urosepsis (community-acquired) GU source = ~20–25% of sepsis
Ceftriaxone (Rocephin) 1–2g IV daily
E. coli is #1 (~80%). Urinary tract is not an anaerobic source. Adjust by Gram stain + culture. Add ampicillin if Enterococcus on Gram stain. Cefepime if Pseudomonas risk (recurrent UTI, indwelling catheter, prior Pseudomonas).
Pip-tazo (Zosyn) 4.5g IV q6h OR Ceftriaxone + Metronidazole (Flagyl) 500 mg IV q8h
True anaerobic source. Anaerobic coverage is appropriate here. Urgent source control (ERCP, IR drainage, surgery) is as critical as antibiotics.
SBP (cirrhosis + ascites)
Ceftriaxone (Rocephin) 2g IV daily
SBP is monomicrobial GNR (E. coli, Klebsiella), does NOT need anaerobic coverage. If healthcare-associated SBP or recent broad abx: cefepime or meropenem.
Vancomycin (Vancocin) (MRSA) + Cefepime only if GNR risk or unstable
Not an anaerobic infection. Most non-necrotizing cellulitis is Group A strep + S. aureus. Vanc alone is often sufficient. Skip Zosyn unless polymicrobial features.
Aspiration pneumonia with lung abscess, empyema, or witnessed large-volume aspiration
Ampicillin-sulbactam (Unasyn) 3g IV q6h OR Pip-tazo (Zosyn) 4.5g IV q6h
Routine "aspiration" CAP does NOT need anaerobic coverage. Reserve for clear anaerobic features: abscess, empyema, putrid sputum, severe dental disease, witnessed aspiration of gastric contents.
Neutropenic fever (ANC < 500)
Cefepime (Maxipime) 2g IV q8h ± Vancomycin
Cefepime monotherapy is the standard. Add vanc only for: hemodynamic instability, line infection, skin/soft tissue source, severe mucositis, or known MRSA colonization. Add micafungin at day 4–5 if persistent fever.
Suspected meningitis CNS source = < 5% of sepsis
Ceftriaxone (Rocephin) 2g IV q12h + Vancomycin + Dexamethasone (Decadron) 0.15 mg/kg IV q6h × 4d
Dex before or with first abx dose. Add ampicillin 2g IV q4h for Listeria if > 50yo, immunocompromised, or pregnant. Add acyclovir if HSV encephalitis suspected.
Necrotizing fasciitis
Vancomycin + Pip-tazo (Zosyn) 4.5g IV q6h + Clindamycin (Cleocin) 900 mg IV q8h
Polymicrobial soft tissue → anaerobes appropriate. Clindamycin = toxin suppression (50S inhibition), not for coverage. Surgical emergency, debridement ASAP.
Suspected fungal sepsis
Micafungin (Mycamine) 100 mg IV daily OR Fluconazole (Diflucan) 800 mg IV load → 400 mg daily
Risk factors: TPN, prior broad-spectrum abx, abdominal surgery, Candida colonization, persistent fever despite antibiotics. Micafungin preferred empirically (broader Candida coverage). Step down to fluconazole if C. albicans confirmed susceptible.
Known prior MDR organism (prior ESBL/CRE culture, MDR colonization, or local antibiogram > 10–20% ESBL)
Reserve carbapenems for documented resistant organisms or high institutional ESBL prevalence. Add micafungin if Candida risk (TPN, lines, abdominal surgery).
🔄 Vancomycin monitoring (2020 ASHP/IDSA): Target AUC/MIC 400–600 using Bayesian software or two-level AUC estimation. Old trough-based dosing (15–20 mcg/mL) caused unnecessary nephrotoxicity. AUC-guided dosing reduces AKI by ~30%.
Anaerobic Coverage (2026 Update)
🔄 2026 Update, Stop reflexively adding anaerobic coverage. New evidence shows that empiric anti-anaerobic agents (pip-tazo, metronidazole, clindamycin) given to critically ill patients without an anaerobic source are associated with increased mortality, C. difficile, VRE colonization, and worse 30-day outcomes, likely from gut microbiome disruption. Chanderraj, 2024
New default empiric for sepsis with no clear source:Vancomycin + Cefepime 2g IV q8h (covers MRSA + Pseudomonas + GNR without anaerobic spectrum).
Add anaerobic coverage (pip-tazo, metronidazole, or carbapenem) ONLY when there is a clear anaerobic source:
Aspiration pneumonia with clear risk, poor dentition, lung abscess, empyema, witnessed large-volume aspiration. Routine CAP-aspiration does NOT need anaerobes.
Oropharyngeal / dental / head & neck, Ludwig's angina, deep neck space infection, odontogenic abscess
Bite wounds, human or animal
If none of the above apply, use Vanc + Cefepime instead of Vanc + Zosyn. This change alone reduces C. diff, AKI, and mortality in mixed-source critical care cohorts.
Vasopressor Guide
Agent
Dose
Receptor
Role
Avoid
Norepinephrine (Levophed) 1ST LINE
0.01–3 mcg/kg/min
α₁>>β₁
First-line. ↑ SVR + mild inotropy
-
Vasopressin (Pitressin) ADD-ON
0.03 units/min (fixed, no titration)
V1/V2
Add vasopressin when NE dose reaches 0.25–0.5 mcg/kg/min (per SSC 2026). Adding vasopressin early allows NE dose reduction (NE-sparing effect). May reduce AKI (V2-mediated water reabsorption). Non-catecholamine → works even in catecholamine-resistant shock (acidosis, downregulated adrenergic receptors). VASST 2008SSC 2026
Cardiac ischemia (coronary vasospasm), mesenteric ischemia at high doses, hyponatremia (V2 effect -monitor Na⁺)
Epinephrine (Adrenalin) 2ND LINE
0.01–0.5 mcg/kg/min
α₁, β₁, β₂
Refractory shock. Adds inotropy.
Falsely elevates lactate (β₂ effect)
Phenylephrine (Neo-Synephrine)
0.5–6 mcg/kg/min
α₁ pure
If tachyarrhythmia limits NE
Low CO states (pure vasoconstriction)
Dobutamine (Dobutrex)
2–20 mcg/kg/min
β₁>β₂
Low CO despite adequate MAP
Without vasopressor if MAP < 65
Dopamine (Intropin) AVOID
-
D1, β₁, α₁
Avoid in sepsis -more arrhythmias, higher mortality SOAP II, 2010
Avoid
Adjuncts
Drug
Indication
Dose
Evidence
Hydrocortisone (Solu-Cortef)
Septic shock with ongoing vasopressor requirement (SSC 2021/2026 -conditional)
De-escalation is mandatory. Broad-spectrum empiric antibiotics carry real harms: C. difficile, fungal infections, nephrotoxicity, resistance selection. Once cultures return, narrow to the narrowest agent that covers the identified organism. Stop antibiotics at 5–7 days if source controlled and patient improving. Use procalcitonin to guide duration.
Clinical Scenario
Why This Empiric
Culture Result
De-Escalate To
Duration
Sepsis, no clear source most common starting point
Vanc + Cefepime, covers MRSA + Pseudomonas + GNR. No anaerobic source → no Zosyn (2026).
Blood cx: MSSA
Stop both. → Cefazolin 2g IV q8h
Bacteremia: 2–4 weeks
Sepsis, no clear source
Vanc + Cefepime, broadest non-anaerobic empiric
Blood cx: MRSA
Stop cefepime. Continue Vancomycin (AUC-guided)
Min 2 weeks, longer if endocarditis
Fever + tachycardia (unclear source) very common, often turns out to be SIRS, not sepsis
Vanc + Cefepime, empiric for possible sepsis without anaerobic source
All cx negative at 48h. PCT < 0.25. Improving.
Stop all antibiotics. Consider non-infectious SIRS?
Stop if no infection identified
CAP (standard) Pulmonary source = ~40–50% of sepsis
Ceftriaxone + Azithro, standard CAP: typicals + atypicals
Vanc + Zosyn, severity warranted broad coverage beyond standard CAP regimen
Sputum: S. pneumoniae (pan-sensitive). MRSA swab neg.
Stop vanc (NPV > 95%). Zosyn → Ceftriaxone 1g IV daily → PO amoxicillin when afebrile
5 days total (PCT-guided)
Urosepsis GU source = ~20–25% of sepsis
Vanc + Cefepime, empiric until source confirmed (no anaerobes, urinary tract is not an anaerobic source)
Urine cx: E. coli (pansensitive)
Stop both. → Ceftriaxone 1g IV daily → PO cipro or TMP-SMX
UTI: 5–7 days. Pyelo: 7–10 days
Pyelonephritis + sepsis
Ceftriaxone 1g IV daily, first-line for community-acquired urosepsis (GNR coverage)
Urine: E. coli (susceptible to cipro + TMP-SMX)
IV → PO ciprofloxacin 500mg BID or TMP-SMX DS BID when afebrile + tolerating PO
7 days total
Perforated appendicitis (post-op) Abdominal source = ~15–20% of sepsis
Zosyn 3.375g IV q6h, GNR + anaerobe coverage for abdominal source
Intra-abdominal: E. coli + Bacteroides (susceptible)
Continue Zosyn → PO amox-clav 875/125 q12h when tolerating PO
4 days post source control STOP-IT, 2015
SBP (cirrhosis + ascites)
Ceftriaxone 2g IV daily, SBP is monomicrobial GNR (E. coli, Klebsiella). Not polymicrobial → does NOT need anaerobic coverage. If healthcare-associated SBP or recent abx: cefepime or meropenem.
Ascitic fluid cx: E. coli. Susceptible to ceftriaxone.
Continue ceftriaxone.
5 days. Repeat paracentesis at 48h, PMN should drop > 25%.
Cellulitis (admitted, severe) Skin/soft tissue source = ~5–10% of sepsis
Vanc + Cefepime, MRSA + GNR. Non-necrotizing cellulitis is NOT an anaerobic infection, skip Zosyn (2026).
Blood cx negative at 48h. No abscess. Non-purulent.
Stop both. → PO cephalexin 500mg q6h. If purulent: TMP-SMX DS BID
5 days
HAP/VAP
Vanc + Cefepime, hospital-acquired = Pseudomonas + MRSA risk. Cefepime preferred over Zosyn (2026), pneumonia is not an anaerobic source unless aspiration with abscess/empyema.
Sputum: Pseudomonas aeruginosa (susceptible to cefepime)
Stop vanc. Continue Cefepime 2g IV q8h
7 days for HAP/VAP
Line sepsis (suspected CLABSI)
Vanc + Cefepime, MRSA + GNR coverage for line infection (line is not an anaerobic source)
Blood cx: Coag-negative Staph (1 of 2 bottles)
Likely contaminant. 1 bottle + improving + no hardware → stop vanc. If 2/2 bottles or prosthetic → treat.
Contaminant: stop. True: 5–7 days (no hardware) or 4–6 wks (prosthetic)
Neutropenic fever
Vanc + Cefepime, cefepime = anti-pseudomonal monotherapy for febrile neutropenia; vanc if line infection suspected
Stop vanc + cefepime. Micafungin → Fluconazole 400mg IV/PO daily. Remove all central lines.
14 days from first negative blood cx
VAP + prior meropenem use
Meropenem + Vanc, prior carbapenem use selects for resistant organisms
Sputum: Stenotrophomonas maltophilia
Stop meropenem (intrinsically resistant). → TMP-SMX 15mg/kg/day IV divided q6-8h
10–14 days. Meropenem selects for Steno.
Necrotizing fasciitis rare, surgical emergency
Vanc + Zosyn, broadest empiric for polymicrobial soft tissue infection
Wound cx: Group A Strep
Stop both. → Penicillin G 4MU IV q4h + Clindamycin 900mg IV q8h (toxin suppression)
Until debridement complete + clinical improvement
The narrowest effective antibiotic is the best antibiotic.
Pimp Questions
What is the Sepsis-3 definition of sepsis vs septic shock?
Sepsis: life-threatening organ dysfunction from dysregulated host response to infection, operationally: suspected infection + SOFA increase ≥ 2. Septic shock: sepsis requiring vasopressors for MAP ≥ 65 plus lactate > 2 despite adequate fluids. Both criteria must be met, a patient on pressors with normal lactate is sepsis, not septic shock. Mortality > 40%.
What does lactate actually measure, and what is "cryptic shock"?
Lactate reflects tissue hypoperfusion + aerobic glycolysis from stress, it is NOT just "anaerobic metabolism." Lactate ≥ 2 with normal BP = "cryptic shock", these patients have the same mortality as overt shock if untreated. Lactate ≥ 4 = mandatory resuscitation regardless of MAP. Target lactate clearance ≥ 10% per 2 hoursANDROMEDA-SHOCK, 2019.
Walk me through the sepsis bundle. What goes first and what's the time target?
Within 1 hour (septic shock) or 3 hours (sepsis without shock) per SSC 2026: (1) Lactate, measured immediately, repeat in 2–4h. (2) Blood cultures × 2, from 2 separate sites before abx, but never delay abx for cultures. (3) Broad-spectrum antibiotics, every hour of delay ≈ +7% mortality. (4) 30 mL/kg balanced crystalloid (LR over NS) if hypotensive or lactate ≥ 4
Why is LR preferred over normal saline? When would you use NS instead?
NS causes hyperchloremic metabolic acidosis → renal afferent vasoconstriction → ↓ GFR → AKI. SMART, 2018: LR/PlasmaLyte reduced death + new renal failure vs NS. Use NS only for: (1) hyponatremia, (2) TBI (LR is slightly hypotonic, risk of cerebral edema), (3) running with blood products (LR has calcium → clots with citrated blood). SSC 2026 strengthened this to "suggest balanced crystalloids over NS."
Your septic patient's MAP is 58 after 2L of crystalloid. What do you do?
Start norepinephrine now, don't keep bolusing.CENSER, 2019: early NE initiation alongside fluids improved shock control. Start peripherally via large-bore IV above antecubital fossa if no central line, SSC 2026 explicitly endorses this. Fluid overload kills: > 5–6L in 24h independently increases mortality, worsens ARDS, delays extubation. Pressors are not a failure, they're the next step.
Why is norepinephrine first-line? What receptor profile makes it ideal for sepsis?
NE is a potent α₁ agonist (vasoconstriction → raises MAP) with mild β₁ (maintains cardiac output without tachycardia). SOAP II, 2010: dopamine caused 2× more arrhythmias (24% vs 12%) with trend toward higher mortality. Dopamine's dose-dependent receptor effects (D1→β₁→α₁) are unpredictable. Phenylephrine (pure α₁) is avoided because it drops CO. Only use pressor-dose epi if also needing inotropic support.
Patient on NE 0.3, MAP still 60. Walk through your vasopressor escalation.
Step 1: Add vasopressin 0.03 units/min (fixed dose, no titration), works via V1 receptors, catecholamine-independent VASST, 2008. Step 2:Hydrocortisone 50 mg IV q6h for ongoing vasopressor-dependent shock ADRENAL, 2018. Step 3: Stop and reassess, (a) source control adequate? (b) bedside echo: is this actually cardiogenic or mixed shock? (c) missed adrenal crisis, hemorrhage, or obstructive cause? More pressors without a diagnosis is not a plan.
When do you give stress-dose steroids? What trial data supports it?
Hydrocortisone 200 mg/day (50 mg IV q6h) for septic shock with ongoing vasopressor requirement (SSC 2021 reversed the 2016 stance; maintained in 2026). ADRENAL, 2018: no mortality benefit but faster shock reversal. APROCCHSS, 2018: hydrocortisone + fludrocortisone DID reduce 90-day mortality.Don't do a cosyntropin stim test first, it doesn't predict who benefits. Taper over 3–5 days after pressors off.
How do you assess fluid responsiveness in a septic patient?
Only ~50% of septic patients are fluid-responsive, giving fluid to non-responders causes harm. Best bedside tests: (1) Passive leg raise (PLR), raise legs to 45°, if CO or pulse pressure increases > 10%, patient is preload-responsive. (2) Pulse pressure variation (PPV) > 13% on arterial line (only valid if mechanically ventilated, Vt ≥ 8, sinus rhythm)
What empiric antibiotics do you choose for undifferentiated septic shock?
Vancomycin + cefepime 2g IV q8h is the new 2026 default, covers MRSA + Pseudomonas + GNR without unnecessary anaerobic spectrum. Chanderraj, 2024 showed empiric anti-anaerobic agents (Zosyn, metronidazole, clinda) given without an anaerobic source ↑ mortality, C. diff, and VRE. Add Zosyn or metronidazole ONLY for clear anaerobic sources: intra-abdominal, aspiration w/ abscess/empyema, nec fasc, pelvic, or bite wounds. MDR / prior ESBL → meropenem 1g q8h. Add micafungin if Candida risk. SSC 2026: 1h for shock, 3h for sepsis without shock.
When should you intubate a septic patient? What are the risks?
Intubate for airway protection (GCS ≤ 8), refractory hypoxemia (SpO₂ < 90% on high-flow), or respiratory fatigue (rising RR, accessory muscle use, rising lactate from breathing work). Danger: intubation in septic shock can cause cardiovascular collapse, induction agents drop SVR + preload, positive pressure ventilation drops venous return.
What is the difference between warm shock and cold shock? How does it change management?
Warm shock (early/classic): high CO + low SVR → warm extremities, bounding pulses, wide pulse pressure, flash CRT. Treat with vasopressors alone.Cold shock: low CO + high SVR → mottled/cool extremities, weak pulses, narrow PP, delayed CRT, low ScvO₂. Treat with vasopressors + dobutamine (start 2.5 mcg/kg/min, max 20). Septic cardiomyopathy occurs in ~40%, biventricular, reversible in 7–10 days. Diagnose with bedside echo (poor EF, dilated LV).
How do you use procalcitonin to guide antibiotic duration?
Check PCT at baseline then q48–72h. Stop antibiotics when: PCT < 0.25 OR ≥ 80% decline from peakPRORATA, 2010: safely reduced abx duration by 2.7 days. False positives (elevated without infection): post-surgery, burns, cardiac arrest, pancreatitis, trauma. False negatives (low despite infection): localized/walled-off infections (abscess, empyema), early infection (< 6h).
What is source control and when does delayed source control kill?
Source control = physically removing the nidus of infection. Antibiotics alone cannot sterilize undrained abscesses, necrotic tissue, or infected hardware. Time-critical sources: (1) necrotizing fasciitis → OR within hours, (2) bowel perforation → surgical repair, (3) cholangitis with stone → ERCP, (4) obstructed pyelonephritis → nephrostomy or stent, (5) infected central line → pull it. Target source control within 6–12 hours.
Patient cleared lactate, on NE 0.06 + vasopressin. How do you wean?
Wean NE first, vasopressin last. Reduce NE by 0.02–0.05 mcg/kg/min q15–30 min while monitoring MAP. Once NE is off → wean vasopressin by 0.01 units/min q30 min. Why vasopressin last? It provides catecholamine-independent vasoconstriction, stopping it first causes rebound hypotension requiring NE re-escalation. Taper hydrocortisone over 3–5 days after all pressors are off, abrupt discontinuation risks adrenal crisis.
An elderly patient presents with AMS and hypotension but no fever. Can this be sepsis?
Absolutely, and this is the most commonly missed presentation. Elderly, immunocompromised (transplant, chemo), and patients on chronic steroids may present with no fever, minimal leukocytosis, and normal HR.Hypothermia (temp < 36°C) and leukopenia in sepsis are very bad prognostic signs, worse outcomes than febrile patients. Think sepsis in any elderly patient with unexplained AMS + hypotension, even with a normal WBC and no fever.
What role does albumin play in sepsis resuscitation?
SSC 2026 reversed course: now suggests crystalloids alone over crystalloids + albumin for initial resuscitation. This flips the 2021 recommendation. Exception: albumin may still be appropriate after large crystalloid volumes or in cirrhosis. SAFE, 2004: no overall benefit vs saline. ALBIOS, 2014: targeting albumin ≥ 3 g/dL did not improve 28-day mortality. Bottom line: don't reflexively add albumin to your resuscitation -crystalloids alone are sufficient for most patients.
How much fluid is too much? When does fluid resuscitation become harmful?
There is no safe "magic number", assess after every bolus. After the initial 30 mL/kg, further fluid should be given only if the patient demonstrates fluid responsiveness (PLR, PPV, or CO response to bolus). Signs of fluid overload: rising FiO₂ requirements, new crackles, worsening P/F ratio, rising CVP with no MAP improvement, positive fluid balance > 5–6L. FACTT, 2006: conservative fluid strategy shortened ventilator days in ARDS.
Clinical Examples
📋 Case 1, Urosepsis with Cryptic Shock
Patient: 78 y/o F with DM2 and CKD3, presents with confusion, dysuria, and fever 39.2°C for 1 day.
Key findings: HR 112, BP 108/68, RR 24. Lactate 4.2, WBC 18.4K, Cr 2.8 (baseline 1.6), UA positive for nitrites and leukocyte esterase.
Management:
Blood cultures x2 drawn, then ceftriaxone 1g IV within 1 hour SSC, 2026
30 mL/kg LR bolus (lactate ≥ 4 = mandatory resuscitation)
Repeat lactate at 2h, clearance ≥ 10% is the target
CT abdomen to rule out renal abscess or obstruction
Teaching point: Cryptic shock, lactate ≥ 4 with normal blood pressure. This patient meets septic shock criteria even though MAP is adequate. Do not be falsely reassured by a normal BP when lactate is elevated.
📋 Case 2, Refractory Septic Shock with Vasopressor Escalation
Patient: 62 y/o M with COPD, presents with productive cough and fevers. CXR shows RLL consolidation. MAP 52 after 2L LR.
Norepinephrine via peripheral IV, do not delay for central line CENSER, 2019
Cefepime 2g IV q8h + vancomycin 25 mg/kg load (pneumonia is not an anaerobic source, SSC 2026 / Chanderraj, 2024 prefers cefepime over Zosyn)
NE at 0.3, MAP still 58, add vasopressin 0.03 u/min VASST, 2008
Hydrocortisone 50 mg IV q6h (ongoing vasopressor-dependent shock) ADRENAL, 2018
Antibiotic Stewardship: Day 2, sputum culture grows S. pneumoniae (pan-sensitive). MRSA nasal swab negative (NPV > 95%). De-escalate: stop vancomycin, narrow cefepime → ceftriaxone 1g IV daily. Check PCT trend, if ≥ 80% decline from peak, target 5-day total course.
Teaching point: Vasopressor escalation: NE first → vasopressin second (fixed 0.03 u/min) → hydrocortisone if still requiring high-dose pressors. Wean NE first, vasopressin last. Always reassess antibiotics at 48-72h when cultures finalize.
📋 Case 3, Sepsis with Procalcitonin-Guided De-escalation
Patient: 55 y/o F, admitted with severe CAP and sepsis. Started on cefepime + vancomycin empirically (SSC 2026, pneumonia is not an anaerobic source).
Narrow cefepime to ceftriaxone (culture-directed for S. pneumoniae)
PCT ≥ 80% decline, stop antibiotics at day 5 PRORATA, 2010
Total duration: 5 days (not the traditional 7-14)
Antibiotic Stewardship: Culture-directed narrowing is the goal. MRSA swab negative → stop vancomycin. Pan-sensitive organism → narrow to simplest effective agent. PCT-guided stop rule avoids unnecessary antibiotic days, fewer C. diff, less resistance, shorter stay.
Teaching point: Procalcitonin-guided de-escalation safely reduces antibiotic duration by 2-3 days. Stop rule: PCT < 0.25 or ≥ 80% decline from peak. Every unnecessary antibiotic day increases C. diff and resistance risk.
📋 Case 4, Urosepsis in Elderly Patient
Patient: 78F from nursing home, altered mental status, T 39.2°C, HR 112, BP 82/48, WBC 22k. Foley catheter in place. UA: positive nitrites, leukocyte esterase, bacteria.
Key findings: Lactate 4.8 mmol/L → septic shock.
Management:
Blood cultures × 2 + urine culture BEFORE antibiotics
Cefepime 2g IV within 1 hour (covers Pseudomonas, catheter-associated UTI risk). Add vancomycin if concerned for MRSA bacteremia.
30 mL/kg LR bolus. Reassess after each liter.
Norepinephrine via peripheral IV, don't wait for central line SSC, 2026
Antibiotic Stewardship: Day 2, urine culture grows E. coli (pan-sensitive). Narrow cefepime → ceftriaxone 1g IV daily. Plan transition to PO ciprofloxacin or TMP-SMX for discharge. Total course: 7-10 days for complicated UTI.
Teaching point: Catheter-associated UTI + septic shock = remove the catheter (source control), cover Pseudomonas empirically, start pressors early, and narrow at 48h when cultures return.
📋 Case 5, Necrotizing Fasciitis
Patient: 55M with diabetes, rapidly spreading erythema on left leg × 12 hours. Pain out of proportion to exam. Crepitus on palpation. T 39.8°C, HR 125, BP 95/58, WBC 28k, lactate 5.2.
This is a surgical emergency, NOT a medical one.
Do NOT wait for LRINEC score if clinical suspicion is high. Pain out of proportion + crepitus + sepsis = OR now.
Vancomycin + pip-tazo + clindamycin (clindamycin inhibits toxin production in Group A Strep)
Emergent surgical consult → radical debridement within hours. Every hour of delay ≈ +7.6% mortality.
Expect return to OR every 24–48h for re-exploration until margins are clean.
Antibiotic Stewardship: Post-debridement, wound cultures guide narrowing. If Group A Strep confirmed → narrow to penicillin G + clindamycin (toxin suppression). If polymicrobial → maintain broad coverage. Duration guided by clinical response, not a fixed number of days.
Teaching point: Nec fasc is a surgical disease with medical support. The antibiotic that matters most is the scalpel. Call surgery BEFORE imaging.
📣 Sample Presentation
One-Liner
"Mr. Torres is a 72-year-old with T2DM and CKD3 who presented with 3 days of fever, dysuria, and confusion. Vitals: BP 82/50, HR 118, Temp 39.1°C. Lactate 4.8. He met criteria for septic shock from presumed urosepsis."
Key Points to Cover on Rounds
Source: urosepsis (urine GNR on gram stain, cultures pending). Antibiotics: ceftriaxone day 2, started within 40 min of arrival. Lactate trending 4.8→2.1→1.4. Hemodynamics: NE weaned from 0.12 to 0.04 mcg/kg/min, MAP 68. UOP 45 mL/hr. Cr 2.1 from baseline 1.4, trending down. Plan: narrow abx when cultures finalize, continue NE wean.
Daily Rounds Checklist
Cultures finalized? → Narrow antibiotics today if possible. What day of antibiotics are we on?
Lactate cleared? → < 2 on two consecutive measurements = adequate perfusion
Vasopressor trajectory → Weaning or escalating? Note exact dose and trend
UOP adequate? → Target ≥ 0.5 mL/kg/hr. If oliguric -reassess volume status + pressor dose
Source controlled? → Drain placed? Infected line removed? Surgery consulted?
Glucose 140–180 mg/dL? → Avoid hypoglycemia; tight control not beneficial NICE-SUGAR, 2009
DVT prophylaxis ordered? Stress ulcer prophylaxis (SUP) indicated?Updated (SCCM/ASHP, 2024): SUP only if coagulopathy (PLT <50K, INR >1.5), shock (on vasopressors), or chronic liver disease. Vent alone is no longer a clear indication. Enteral feeding is protective, if tolerating feeds, SUP is likely unnecessary. Discontinue when risk factors resolve.
Nutrition started? → Enteral preferred within 24–48h if hemodynamically stable
De-escalate antibiotics based on growth + sensitivities
Procalcitonin
q48–72h
If falling and < 0.25 → consider stopping antibiotics PRORATA 2010
Coags (INR, fibrinogen, D-dimer)
Daily if coagulopathy
Fibrinogen < 1.5 + falling = DIC
Temperature
Continuous
Hypothermia = worse prognosis than fever
Organ Support Targets
Renal
AKI develops in 40–50% of septic shock. Avoid nephrotoxins (NSAIDs, aminoglycosides, contrast if possible). CRRT (continuous renal replacement) preferred over IHD in hemodynamically unstable patients. Initiate CRRT for refractory acidosis, hyperkalemia, or volume overload.
Coagulation / DIC
DIC complicates ~35% of septic shock. Treat with FFP if bleeding + INR > 1.5. Platelet transfusion if < 10k (or < 50k if bleeding). Avoid prophylactic FFP unless procedure planned.
Respiratory
Avoid intubation if possible -try HFNC or NIV for early respiratory compromise. If intubated: lung-protective ventilation (TV 6 mL/kg PBW, Pplat ≤ 30). Daily SAT + SBT per ABCDEF bundle.
Antibiotic Duration
Standard: 5–7 days for bacteremia with good source control. Do not continue antibiotics empirically "just in case." Use procalcitonin trend + clinical response.
Certain infections require longer: endocarditis (4–6 weeks), osteomyelitis (6 weeks -oral step-down is acceptable OVIVA, 2019), S. aureus bacteremia (minimum 14 days from first negative culture).
⚡ Summary
Summary
Define It by Organ Dysfunction
Sepsis is life-threatening organ dysfunction from infection, SOFA rise of 2 or more.Septic shock is vasopressor-requiring hypotension with a lactate above 2 despite adequate fluid, and it carries far higher mortality. SIRS was abandoned because it is present in almost every ill inpatient and cannot distinguish sepsis from a bad flu.
Screen With NEWS or MEWS, Not qSOFA
SSC 2026 moved away from qSOFA because its sensitivity is poor and it misses too many septic patients.NEWS 7 or above is an emergency; MEWS 5 or above needs urgent review.qSOFA remains a rapid bedside prompt, never a definition, and a score of 0 does not exclude sepsis.
Antibiotic Timing Now Splits by Severity
Septic shock: everything within 1 hour.Sepsis without shock: antibiotics within 3 hours, which is a change from the previous 1-hour-for-all standard and allows a short diagnostic window when the picture is uncertain. Each hour of delay in septic shock raises mortality by roughly 7%, so culture then treat, and never wait for results.
Run the Bundle, Then Reassess
Lactate, two sets of blood cultures before antibiotics, broad-spectrum antibiotics, 30 mL/kg of balanced crystalloid, and vasopressors for a MAP below 65.Recheck lactate every 2 hours, targeting at least 10% clearance. Failure to clear despite resuscitation means inadequate source control, occult bleeding or mitochondrial dysfunction, not simply more fluid.
Fluid: Balanced, Bolused, Then Stopped
Lactated Ringer or Plasma-Lyte over normal saline, which causes hyperchloremic acidosis. Give 30 mL/kg initially, then reassess responsiveness rather than continuing on protocol. Fluid overload kills, so once the patient is no longer fluid-responsive, switch to vasopressors and start de-resuscitating when stable.
Norepinephrine First, and Start It Early
Norepinephrine is first line and can be started peripherally per SSC 2026, so central access should never delay it. Add vasopressin 0.03 units/min once norepinephrine reaches 0.25 to 0.5 mcg/kg/min, which is catecholamine-sparing. Hydrocortisone 200 mg/day for shock that remains vasopressor-dependent.Dobutamine for a low cardiac output despite adequate filling.
Do Not Add Anaerobic Cover Reflexively
Vancomycin plus cefepime is the 2026 default when there is no anaerobic source, based on evidence that unnecessary anaerobic coverage disrupts the gut microbiome and is associated with worse outcomes (Chanderraj 2024). Add piperacillin-tazobactam or metronidazole only for an intra-abdominal, aspiration-with-abscess, necrotizing, pelvic or bite-wound source.
Source Control Is Equal to Antibiotics
Antibiotics alone fail in an undrained source.Find it, drain it, remove the line, consult surgery, target 6 to 12 hours. Abscess to interventional radiology or the operating room, necrotizing fasciitis to emergent debridement without waiting for imaging, cholangitis or obstructed urinary tract to urgent decompression. Then reassess at 48 to 72 hours: narrow to culture-directed therapy, stop empiric MRSA cover if cultures are negative, and treat for 5 to 7 days in most patients. Watch for the patient who does not look septic: the elderly, the immunosuppressed and those on steroids may have no fever and no leukocytosis, and hypothermia with leukopenia is an ominous sign.
SIRS: ≥ 2 of temp >38/<36, HR >90, RR >20, WBC >12k/<4k (historical, high sensitivity triage)
Lactate ≥ 4 = cryptic shock even if BP normal
🦠 Common Sources MOST → LEAST
🫁 Pulmonary ~40–50% (pneumonia)
🚿 GU ~20–25% (urosepsis)
🫀 Intra-abdominal ~15–20%
🩹 Skin/soft tissue ~5–10%
💉 Line / device ~5%
🧠 CNS / endocarditis < 5%
❓ No source identified ~10–15%
⏱️ Sepsis Bundle SSC 2026
1
Lactate -measure now, repeat if > 2 in 2h. Target clearance ≥ 10%.
2
Blood cultures × 2 -before antibiotics. UA + urine Cx. Don't delay abx > 45 min.
3
Antibiotics:Vanc + Cefepime default (2026, no anaerobic source → no Zosyn). Add Zosyn/metronidazole only for intra-abdominal, aspiration w/ abscess, nec fasc, pelvic, or bite wound. Meropenem if prior ESBL/MDR. 1h for septic shock, 3h for sepsis without shock.
4
30 mL/kg LR/PlasmaLyte if MAP < 65 or lactate ≥ 4. Stop if no response. SMART 2018
5
Vasopressors: NE first-line if MAP < 65 despite fluids. SOAP II, 2010
Acute worsening of HF symptoms requiring urgent intervention. Classify the hemodynamic profile first (Warm/Cold × Wet/Dry) -it drives everything. For chronic HF and GDMT optimization, see Heart Failure (Chronic).
🔍 Overview
Hemodynamic Profiles (Stevenson / Forrester)
Classify your patient before reaching for diuretics. The profile drives the entire management strategy.
Profile
Perfusion
Congestion
Management
Warm & Wet (~70%)
Adequate (warm extremities, normal mentation)
Yes (JVD, edema, crackles)
IV diuresis. This is the most common profile. Furosemide, monitor UOP, daily weights.
Cold & Wet (~20%)
Impaired (cold, clammy, AMS, low UOP)
Yes
ICU. Inotropes (dobutamine/milrinone) + diuresis. May need invasive monitoring. Consider mechanical circulatory support (MCS) early.
IV furosemide -start at 1–2.5× the home oral dose IV. If diuretic-naive, start 40 mg IV. Monitor UOP every hour -target 0.5–1 mL/kg/hr. UOP < 200 mL in 2 hrs = inadequate response.
Step 2 -Diuretic Resistance
Double the furosemide dose OR add metolazone 2.5–5 mg PO 30 min before furosemide (sequential nephron blockade) DOSE, 2011. Or switch to continuous furosemide infusion (10–40 mg/hr). Acetazolamide 500 mg IV daily as adjunct to loop diuretics improves decongestion ADVOR, 2022. Monitor K⁺ and Mg closely -replace aggressively.
Step 3 -Vasodilators (if hypertensive)
Nitroglycerin drip 5–200 mcg/min -reduces preload, improves dyspnea rapidly. Ideal for flash pulmonary edema with SBP > 140. Or nitroprusside 0.3–5 mcg/kg/min (afterload + preload reduction) -requires arterial line, cyanide toxicity risk > 48h. Avoid vasodilators if SBP < 90.
Step 4 -Respiratory Support
BiPAP/CPAP for acute pulmonary edema -reduces work of breathing, ↓ preload, ↓ afterload, buys time for diuretics to work. 3CPO, 2008: NIV reduced dyspnea and physiologic distress but no mortality benefit vs standard O₂. Intubate if: worsening hypoxia despite NIV, RR > 35, inability to protect airway, hemodynamic collapse.
Monitoring
Daily weights (gold standard for tracking decongestion). Daily BMP. UOP q1h (Foley recommended). Cr bump ≤ 0.3 mg/dL acceptable ("acceptable cardiorenal syndrome"). Net negative 1–2 L/day is a reasonable target.
Transition to Oral
When clinically euvolemic: JVD resolved, crackles gone, comfortable on exertion, at dry weight. Convert to oral furosemide at 2× IV dose. Reassess at 24 hrs before discharge.
Cold & Wet / Low Output -DO NOT give aggressive diuretics alone. These patients need inotropic support (dobutamine or milrinone) before or alongside diuresis. ICU admission. Consider MCS early if deteriorating. See Cardiogenic Shock topic.
💊 ADHF Medications
Acute Agents
Drug (Brand)
Dose
Role
Key Notes
Furosemide (Lasix) 1ST LINE
40–200 mg IV bolus or 10–40 mg/hr infusion
First-line diuretic. Decongestion.
1–2.5× home oral dose IV. Monitor UOP, K⁺, Mg, Cr daily. Continuous infusion may cause less ototoxicity than large boluses.
Bumetanide (Bumex) ALTERNATIVE
1–4 mg IV
Alternative loop diuretic. 40:1 ratio (furosemide 40 mg ≈ bumetanide 1 mg).
More predictable oral bioavailability than furosemide. Some prefer in outpatient setting.
Thiazide-like. Works even at low GFR (unlike HCTZ). Massive electrolyte shifts -monitor K⁺, Mg, Na aggressively.
Chlorothiazide (Diuril) ADD-ON (IV)
500–1000 mg IV 30 min before loop diuretic
IV thiazide for sequential nephron blockade. Use when NPO or fast onset needed.
Only IV thiazide in US. Onset 15 min, duration 6–12h. Fails below eGFR 30 (unlike metolazone). Expensive (~$40–80 per dose). Severe hypokalemia, hyponatremia -monitor K⁺, Mg, Na aggressively. Dose BEFORE the loop, never after.
Acetazolamide (Diamox) ADD-ON
500 mg IV daily × 3 days
Proximal tubule block (carbonic anhydrase inhibitor). Add-on for diuretic resistance and when metabolic alkalosis develops from loop diuresis.
ADVOR, 2022: successful decongestion at day 3 42% vs 30% (12% absolute increase, NNT < 9; RR 1.46) when added to loop. Works upstream of the loop so it stacks with thiazide (different site). Watch for metabolic acidosis (expected from mechanism) and hypokalemia. Dose-reduce at low eGFR.
Tolvaptan (Samsca) AQUARETIC / NICHE
15–30 mg PO daily (inpatient start only)
V2 receptor antagonist (aquaretic). Excretes free water only, no Na effect. For hypervolemic hyponatremia (Na < 125) when further diuresis would worsen sodium.
EVEREST, 2007: symptom and weight benefit, no mortality benefit. Must start inpatient -rapid Na correction risk (ODS). Avoid in cirrhosis (hepatotoxicity). Short-term bridge only.
Nitroglycerin (Tridil) HYPERTENSIVE ADHF
5–200 mcg/min IV drip
Preload reduction. Rapid relief of dyspnea in flash pulmonary edema with SBP > 140.
Venodilator predominantly. Titrate to symptom relief. Avoid if SBP < 90, severe AS, RV infarct, or PDE5 inhibitor use (sildenafil within 24h).
Requires arterial line. Cyanide toxicity risk > 48h or > 2 mcg/kg/min. Thiocyanate levels if prolonged. Avoid in renal failure (thiocyanate accumulation).
Dobutamine (Dobutrex) COLD & WET
2–20 mcg/kg/min IV
Inotrope for low-output state. Cold & Wet profile.
↑ CO, ↑ HR. Never use alone if MAP < 65 -pair with NE. Tachyphylaxis after 72h. See Inotropes Guide.
Milrinone (Primacor) COLD & WET / RV
0.125–0.75 mcg/kg/min IV (skip loading dose)
Inodilator. RV failure, pulmonary HTN, patients on chronic BB.
↓ PVR (key advantage in RV failure). Renally cleared -dose-adjust in AKI. Longer half-life (2–3h) than dobutamine's ~2 min.
Norepinephrine (Levophed) 1ST LINE PRESSOR
0.05–1 mcg/kg/min IV (titrate to MAP ≥ 65)
First-line vasopressor for hypotension or cardiogenic shock complicating ADHF. Pair with dobutamine or milrinone if low CO.
SOAP II, 2010: preferred over dopamine (fewer arrhythmias, better cardiogenic shock outcomes). Central line preferred (extravasation necrosis risk peripherally). Once pressors needed, hold ACEi/ARB/ARNI, BB, MRA, SGLT2i until off pressors.
Ferric carboxymaltose (Injectafer) INPATIENT IRON
15 mg/kg IV (max 750 mg/dose) × 2 doses separated by ≥ 7 days
Iron repletion in iron-deficient HF. Give during admission, not outpatient, for maximum event reduction.
AFFIRM-AHF, 2020: 26% reduction in HF hospitalizations at 52 weeks. Criteria: ferritin < 100 OR ferritin 100–299 + TSAT < 20%. Screen every ADHF admission. Avoid in active infection. Rare anaphylaxis (safer than older iron dextran).
GDMT in ADHF -What to Do
Do not stop GDMT abruptly during ADHF hospitalization. Continue at reduced doses if needed. The exception: frank cardiogenic shock → hold everything until stabilized.
START: norepinephrine for MAP, plus dobutamine for low CO (milrinone preferred if RV failure or pulmonary HTN)
CONTINUE (at adjusted dose): loop diuretic, titrated to UOP and MAP. Decongestion is still needed, just carefully.
Resume sequentially once off pressors, MAP stable > 65, and Cr not rising: ACEi/ARB first, then beta-blocker, then MRA, then SGLT2i. Titrate back to home doses before discharge.
Outside of frank cardiogenic shock, reduce, don't stop. B-CONVINCED 2009 established continuing beta-blockers through ADHF was safer than stopping them. Abrupt BB withdrawal causes rebound tachycardia and ischemia.
Meds to Come OFF at Admission
These aren't GDMT, but they drive or perpetuate HF. Review the full med list on admission and deprescribe aggressively. Missing these is a common rounding oversight.
PPAR-γ activation drives Na and water retention. Increased HF hospitalization; contraindicated in NYHA III-IV.
Switch diabetes management to SGLT2i or GLP-1 RA (both reduce HF events).
Saxagliptin HOLD / SWITCH
SAVOR-TIMI 53 showed an increased HF hospitalization signal. Sitagliptin and linagliptin appear safer.
Switch to sitagliptin, or better, to SGLT2i or GLP-1 RA.
Pregabalin / gabapentin HOLD
Peripheral edema is common and can mimic or worsen HF volume overload.
Especially hold if edema is disproportionate to the congestion picture. Consider duloxetine or TCA for neuropathic pain.
High-dose glucocorticoids MINIMIZE
Mineralocorticoid activity at high doses drives Na and water retention, HTN.
Not always possible to stop (autoimmune disease). Use lowest effective dose. Hydrocortisone has less mineralocorticoid effect at replacement doses.
Anti-arrhythmics with negative inotropy (flecainide, propafenone, disopyramide) AVOID in HFrEF
Class IC agents increase mortality in structural heart disease (CAST). Disopyramide is negatively inotropic.
Amiodarone and dofetilide are the only rhythm-control agents considered safe in HFrEF.
Excess IV fluids STOP
Overzealous maintenance fluids or high-Na medication carriers undo diuresis. Reconcile total Na and volume intake daily.
Convert IV meds to concentrated formulations. Use D5W as carrier when a drip is essential.
For full chronic GDMT optimization (the four pillars, titration targets, key trials), see Heart Failure (Chronic).
🪜 Diuretic Escalation Ladder
The Ladder, Step by Step
Most "diuretic resistance" is actually under-dosed loop OR an unaddressed reversible cause. Work through this order; don't skip rungs.
Step 0: Address reversible causes first. Stop NSAIDs (prostaglandin inhibition blunts loop response). Treat hypotension (kidneys can't diurese if MAP is too low, may need pressors to perfuse them). Switch PO to IV when gut edema is present. Check TSH (hypothyroid fluid retention mimics resistance). Consider bilateral renal artery stenosis if ACE-induced AKI pattern.
Step 1: Max the loop. Double the IV dose (up to 200 mg furosemide IV bolus), switch from PO to IV, or start a continuous infusion (10-40 mg/hr). Gut edema makes PO absorption unreliable, so IV is the default in ADHF.
Step 2: Add a tubular co-blocker (sequential nephron blockade). Two options at different tubular sites that can be used alone or stacked: thiazide (metolazone PO or Diuril IV) blocks the distal tubule, and acetazolamide 500 mg IV daily × 3 blocks the proximal tubule. ADVOR 2022: acetazolamide added to loop produced successful decongestion in 42% vs 30% at day 3 (12% absolute increase, NNT < 9; RR 1.46). Acetazolamide is particularly useful when loop diuresis has caused metabolic alkalosis. Give the thiazide 30-60 min before the loop.
Step 3: Start an SGLT2 inhibitor if not already on one. Dapagliflozin 10 mg PO or empagliflozin 10 mg PO. EMPULSE / EMPAG-HF 2022: in-hospital start during ADHF reduced weight, NT-proBNP, and clinical events. Also foundational GDMT with mortality benefit. Drop the loop dose ~25% when starting to avoid over-diuresis.
Step 4: Albumin + furosemide sandwich if serum albumin < 2.5 g/dL. See full breakdown at the bottom of this section.
Step 5: Tolvaptan if hypervolemic AND hyponatremic (Na < 125). Blocks ADH at the collecting duct so the kidney excretes free water only, no Na effect. Must start inpatient (rapid-correction risk). Avoid in liver disease. EVEREST 2007 showed symptom and weight benefit without mortality benefit.
Step 6: Ultrafiltration or dialysis if all pharmacologic options fail and the patient remains volume-overloaded with AKI or refractory acidosis.
Furosemide vs Diuril vs Metolazone
Feature
Furosemide (Lasix)
Chlorothiazide (Diuril)
Metolazone (Zaroxolyn)
Class
Loop
Thiazide (IV only in US)
Thiazide-like (PO only)
Role
Primary diuretic
Add-on for resistance
Add-on for resistance
Site of action
Thick ascending limb (NKCC2)
Distal tubule (NCC)
Distal tubule (NCC)
Route
IV or PO
IV only
PO only
Typical dose
20-200+ mg IV
500-1000 mg IV
2.5-10 mg PO
Onset
IV 5 min / PO 30 min
IV 15 min
PO 60 min
Duration
~2 h
6-12 h
12-24 h (longest)
% filtered Na blocked (alone)
~25% (most potent single agent)
~3-5%
~5%
Works at eGFR < 30?
Yes
No
Yes (unique among thiazides)
Cost per dose
Pennies
~$40-80
Pennies
Main toxicities
Hypokalemia, hypomagnesemia, ototoxicity (high dose / rapid push), pre-renal AKI
Severe hypokalemia, hyponatremia, hypomagnesemia
Same as Diuril but longer and more profound (24h action window)
One-liner
The engine
Fast IV turbo
Long-acting PO turbo
Which Thiazide When?
Patient can swallow, any eGFR: metolazone 2.5-10 mg PO 30-60 min before the loop. Default choice. Cheap, long-acting, works in advanced CKD.
NPO, or need fast predictable onset: Diuril 500-1000 mg IV 30 min before the loop. Works in 15 min. Expensive. Fails below eGFR 30.
eGFR < 30: metolazone is the only option. Diuril and HCTZ lose efficacy at this level of renal function.
Two common mistakes:
Reaching for Diuril when metolazone PO would work. Diuril is expensive ($40-80 per dose vs pennies for metolazone) and shorter-acting. If the patient can swallow and isn't in fulminant gut edema, metolazone is the default.
Giving the thiazide after or with the loop. The synergy depends on the thiazide being at the distal tubule BEFORE the loop dumps Na downstream. Dose the thiazide 30-60 min first, every time.
Key Adjuncts (Beyond Loop + Thiazide)
Drug
Dose
Mechanism
When to reach for it
Acetazolamide (Diamox) ADVOR 2022
500 mg IV daily × 3 days
Proximal tubule carbonic anhydrase inhibitor. Blocks Na/HCO₃ reabsorption upstream of the loop.
Added to loop in ADHF → 46% more successful decongestion at day 3. Especially useful when loop diuresis has caused metabolic alkalosis. Can stack with thiazide (different site).
Dapagliflozin / Empagliflozin GDMT + DIURESIS
Dapa 10 mg PO / Empa 10 mg PO daily
Proximal tubule SGLT2 block. Modest natriuresis plus mortality/HF-hospitalization benefit independent of diabetes.
Start in-hospital during ADHF if not already on one. EMPULSE / EMPAG-HF 2022 showed reduced weight, NT-proBNP, clinical events. Drop loop ~25% to avoid over-diuresis.
Tolvaptan (Samsca) NICHE
15-30 mg PO daily (inpatient start only)
V2 receptor antagonist (aquaretic). Blocks ADH at collecting duct. Excretes free water only, no Na effect.
Hypervolemic AND hyponatremic (Na < 125) when further diuresis would worsen sodium. Liver toxicity limits long-term use. Avoid in cirrhosis.
Hypertonic saline + high-dose furosemide NICHE / EU
3% saline 150 mL + furosemide 250-500 mg IV, BID
Tonicity gradient mobilizes interstitial Na back into the vascular space, so the loop has more Na to excrete.
Refractory HF failing standard escalation. More European than US practice. SMAC-HF 2011. Avoid if Na > 140.
Step 0 checklist: reversible causes of "diuretic resistance" to rule out FIRST
Bilateral renal artery stenosis, ACE-induced AKI looks like diuretic resistance. Consider if Cr jumps on ACEi/ARB with diuretic.
Non-adherence to sodium restriction, ask the family what the patient is actually eating.
Hypoalbuminemia < 2.5, impairs loop delivery to its tubular target (see sandwich, Step 4).
What NOT to do (classic traps):
"Renal-dose dopamine" (1-3 mcg/kg/min), no benefit. ROSE-HF 2013 was the definitive nail in the coffin. Don't order it.
Nesiritide (recombinant BNP), ASCEND-HF 2011 neutral on outcomes, increases hypotension. Abandoned in most centers.
Aggressive fluid restriction in cardiogenic shock, the kidneys need perfusion pressure. Restricting fluid here worsens AKI without improving congestion.
Albumin + Furosemide "Sandwich" (Step 4 of the Ladder)
For diuretic-resistant edema in hypoalbuminemic patients. Two mechanisms combined:
Oncotic pull. Albumin raises plasma oncotic pressure, mobilizing interstitial fluid back into the vascular space so the loop has volume to diurese.
Drug delivery. Furosemide is ~95% albumin-bound. In hypoalbuminemia, less drug reaches the proximal tubule for active secretion, so less reaches its NKCC2 target. Supplementing albumin restores drug delivery to the thick ascending limb.
When to use (BOTH required):
Diuretic-resistant edema despite max loop + thiazide
Serum albumin < 2.5 g/dL
Classic settings:
Nephrotic syndrome with anasarca
Cirrhotic refractory edema
ICU third-spacing / capillary leak
Post-op volume overload with low albumin
Dosing:
Albumin 25% 100 mL IV (25 g) over 30 min
Then furosemide 40-80 mg IV push at the end of the infusion
Repeat q6-12h if needed
Don't use if albumin is normal. Expensive placebo with no benefit. Effect is transient (hours), so it's a bridge, not a fix. Watch for flash pulmonary edema if the heart can't handle the mobilized volume.
📋 On Rounds
On Rounds
Pimp Questions
What is cardiorenal syndrome and when should you stop diuresing?
Worsening renal function during HF treatment. A Cr bump of ≤ 0.3 mg/dL is acceptable and does not indicate stopping diuresis. It's often from reduced renal perfusion pressure -continue if congestion persists. Stop or slow if Cr rising > 0.5 or K⁺ becoming dangerous.
Why should beta-blockers NOT be started in acute decompensation?
Starting beta-blockers in a decompensated state (where cardiac output is already low) can precipitate cardiogenic shock. Wait until the patient is euvolemic and stable. However, do NOT stop them if already on them -abrupt discontinuation worsens outcomes.
What are the 4 pillars of GDMT for HFrEF and why must you start all four?
(1) ARNI (sacubitril-valsartan) or ACEi/ARB, (2) Evidence-based beta-blocker (carvedilol, metoprolol succinate, bisoprolol -NOT atenolol/metoprolol tartrate), (3) MRA (spironolactone or eplerenone), (4) SGLT2 inhibitor (dapagliflozin or empagliflozin). Each independently reduces mortality by 15-30%. Combined, they reduce mortality ~70% vs placebo. Start all four early -don't wait to titrate one before starting the next.
How do you know if your diuretic dose is working in ADHF, and when should you escalate?
Track net fluid balance, daily weights, and urine output -not BNP. Good diuretic response: UOP 100-150 mL/hr in first 2h after IV furosemide, net negative 1-2L/day, weight loss 0.5-1 kg/day. If inadequate response (UOP < 100 mL in 2h): double the IV dose (ceiling effect -need higher dose to reach threshold in Loop of Henle). If still inadequate → add metolazone 5 mg PO 30 min before furosemide (sequential nephron blockade).
Clinical Examples
📋 Case 1, Warm and Wet with Diuretic Resistance
Patient: 68 y/o M with HFrEF (EF 25%), presenting with 10-lb weight gain, orthopnea, and bilateral leg edema. Home furosemide 80 mg PO BID.
Teaching point: Diuretic resistance requires dose escalation (ceiling effect), then sequential nephron blockade with metolazone. A Cr bump ≤ 0.3 is acceptable during active diuresis.
📋 Case 2, Cold and Wet Requiring Inotropes
Patient: 72 y/o F with HFrEF (EF 15%), presents with confusion, cool mottled extremities, and anasarca. SBP 78.
ICU admission, cold and wet profile (low CO + congestion)
Start dobutamine 5 mcg/kg/min to improve cardiac output before diuresis
Once MAP improves, add IV furosemide for decongestion
Reduce BB dose but do NOT discontinue abruptly
Teaching point: Cold and wet is the most dangerous profile. These patients need inotropes before diuresis, you cannot diurese a heart that is not generating adequate forward flow.
📋 Case 3, New-Onset HFrEF with AF Trigger
Patient: 58 y/o M, no cardiac history, 1 week of progressive dyspnea with new AF and RVR (HR 152).
Key findings: JVP 12 cm, S3 gallop, BNP 2,800. Echo: EF 30%, dilated LV, moderate MR.
Management:
Rate control with IV amiodarone (avoid diltiazem in HFrEF, negative inotrope)
IV furosemide 40 mg (diuretic-naive starting dose)
Anticoagulation for AF, coronary angiogram to rule out ischemic etiology
Teaching point: Tachycardia-mediated cardiomyopathy from uncontrolled AF is reversible with rate/rhythm control. Start all 4 GDMT pillars early, do not wait to titrate one before starting the next.
📋 Sample Presentation
"Mr. Davis is a 74-year-old with HFrEF (EF 30%) presenting with 5 days of worsening dyspnea, 8-pound weight gain, and 3-pillow orthopnea. He was started on his home furosemide 80 mg daily last week but ran out. His BNP is 2,400, creatinine is 1.4 from baseline 1.1, and CXR shows pulmonary edema. He is warm and wet -he received IV furosemide 80 mg with 1,400 mL of UOP in the first 6 hours. He's on day 2, down 2.6 kg from admission weight, creatinine 1.5, K⁺ 3.4 for which we're repleting. GDMT is continued. Plan is to transition to oral diuresis today and target discharge tomorrow if he remains comfortable."
📋 Case 4, New HFrEF: Rapid GDMT Initiation (STRONG-HF)
Patient: 58M with newly diagnosed HFrEF (EF 25%), BP 118/72, HR 78, K⁺ 4.2, Cr 1.1. Currently on no cardiac medications.
🔄 Old approach: Start ACEi → wait weeks → add BB → wait weeks → add MRA → months later maybe ARNI. Patients spent months without full therapy.
New approach (2022 AHA/ACC, STRONG-HF, 2022): Start all 4 pillars within 1–2 weeks at low doses. Don't wait for one to reach target before starting the next.
Timepoint
Action
Day 1 (Admission)
SGLT2i: Dapagliflozin (Farxiga) 10mg daily -start immediately, no titration needed, minimal BP effect. Easiest pillar to add on day 1.
Day 2–3
ARNI: Sacubitril-valsartan (Entresto) 24/26mg BID -if SBP > 100 and off pressors. Go straight to ARNI (skip ACEi if new diagnosis). If already on ACEi, must wash out 36h before starting ARNI. Check BMP: K⁺ and Cr before adding MRA.
Day 3–5 (once near-euvolemic, off pressors)
Beta-blocker: Carvedilol (Coreg) 3.125mg BID -start low. Do NOT start during active decompensation or on inotropes (risk of cardiogenic shock). Wait until diuresis has taken effect and hemodynamics are stable. MRA: Spironolactone (Aldactone) 25mg daily -if K⁺ < 5.0 and eGFR > 30.
All 4 pillars on board within 1 week. Now uptitrate in parallel:
Week 2
Entresto → 49/51mg BID, carvedilol → 6.25mg BID (if BP and HR tolerate).
Each drug reduces mortality independently -every day without full GDMT is a missed opportunity.
Hypotension (SBP < 90) is the main limiting factor -prioritize ARNI > BB > MRA if BP-limited.
"Creatinine bumps" of 0.3–0.5 are acceptable when starting RAAS inhibitors -don't reflexively stop.
SGLT2i + MRA together are safe -monitor K⁺ but the risk of hyperkalemia is lower than feared.
📋 Case 5, Warm & Wet Decompensation (Known HFrEF)
Patient: 64F with known HFrEF (EF 20%), presents with orthopnea, PND, bilateral crackles, JVP 14cm, 2+ pitting edema. BP 142/88, SpO₂ 90% on RA.
Profile: Wet & Warm (congested, adequate perfusion) -most common presentation.
Immediate:
Sit upright, O₂ to maintain SpO₂ > 92%. BiPAP if respiratory distress.
Furosemide (Lasix) 80mg IV push (give 2× their home oral dose as IV dose -she takes 40mg PO daily → give 80mg IV; can escalate to 100mg / 2.5× if prior dose was inadequate). Can redose in 2h if < 100mL UOP.
If inadequate response: double the dose → 160mg IV. If still inadequate → add metolazone (Zaroxolyn) 5mg PO 30 min before next lasix dose (sequential nephron blockade).
Monitoring: Strict I&Os, daily weights (goal: net negative 1–2L/day), BMP BID (watch K⁺ and Cr -"creatinine bumps" of 0.3–0.5 are acceptable if patient is decongesting).
Home GDMT: Continue metoprolol succinate (Toprol XL) at current dose (do NOT uptitrate during decompensation, but do NOT stop unless cardiogenic shock). Hold ACEi/ARNI if hypotensive or Cr rising sharply.
Discharge when: Stable on oral diuretics × 24h, ambulatory SpO₂ > 92%, weight at or near dry weight, scheduled HF clinic follow-up within 7 days.
EF improvement on GDMT may reclassify HFrEF → HFimpEF. Continue all GDMT even if EF improves.
Telemetry
Continuous during IV diuresis and inotrope use
Monitor for AF, VT, bradycardia from BB/digoxin. Discontinue when stable on oral regimen.
Functional status
Each assessment
Dyspnea improvement, orthopnea resolution, exercise tolerance, appetite. The exam matters more than the labs.
Before discharge: Stable on oral diuretics ≥ 24h, weight trending down or at dry weight, BMP stable, GDMT initiated or uptitrated, follow-up within 7 days, patient weighed and educated on daily weights and 2g Na restriction.
BNP/NT-proBNP is the cornerstone biomarker. BNP >400 or NT-proBNP >900 (age-adjusted) strongly supports HF diagnosis. Always obtain an echocardiogram to classify EF and guide therapy.
Test
Rationale
Key Values
BNP / NT-proBNP
Diagnosis and prognostication. Trend to assess treatment response.
BNP >400 pg/mL or NT-proBNP >900 pg/mL (age <75) supports HF. Obesity falsely lowers BNP. Full high/low breakdown ↓
BNP and NT-proBNP are released when cardiac myocytes are stretched by pressure or volume overload (proBNP is cleaved 1:1 into active BNP and inert NT-proBNP). Anything that stretches the heart raises them. The traps are that several non-cardiac conditions raise them without heart failure, and a handful of conditions keep them deceptively low even when HF is real. Always read the number against the patient in front of you, not in isolation.
Conditions that RAISE BNP (most common first)
Condition
Why it raises BNP
Cardiac (the signal you want)
Heart failure (HFrEF and HFpEF)
Volume and pressure overload stretch the ventricular wall, the intended diagnostic signal. Degree of elevation tracks severity and prognosis.
Atrial fibrillation
Atrial stretch plus the rapid ventricular rate raise BNP independent of HF, so new AF can push BNP into the “HF range” and muddy the diagnosis. Interpret cautiously in AF.
ACS / myocardial ischemia
Ischemic wall stress and stunning raise BNP; a high BNP post-MI predicts higher HF and mortality risk (prognostic, not just diagnostic).
Valvular disease (AS, MR)
Chronic pressure (AS) or volume (MR) load stretches the ventricle even before symptoms; rising BNP can flag the time for intervention.
Direct myocardial injury or stress releases BNP transiently.
Non-cardiac (raises BNP without HF, the traps)
Older age
BNP rises with age regardless of HF. Use age-adjusted NT-proBNP cutoffs: <450 (age <50), <900 (50–75), <1800 (>75) pg/mL to rule in acute HF.
CKD / renal failure
Reduced clearance raises baseline levels. NT-proBNP is affected more than BNP because NT-proBNP is cleared only by the kidney. Use higher cutoffs in CKD and trend rather than relying on a single value.
Pulmonary embolism
Acute RV pressure overload stretches the right ventricle; an elevated BNP in PE marks RV strain and worse prognosis (risk-stratification, not diagnosis).
Pulmonary hypertension, cor pulmonale, severe COPD
Chronic RV pressure overload stretches the RV, raising BNP from the right side of the heart.
Sepsis / critical illness
Cytokine-mediated myocardial depression plus volume shifts raise BNP; very common in the ICU and a frequent reason a BNP is hard to interpret there.
Female sex
Higher baseline BNP than men at any given age, a population effect to keep in mind near cutoffs.
Anemia, high-output states (cirrhosis, hyperthyroidism)
Increased cardiac work and circulating volume raise wall stress and therefore BNP.
Conditions that keep BNP DECEPTIVELY LOW (false negatives, HF is present but BNP underwhelms)
Condition
Why BNP is low despite real HF
Obesity (especially BMI >35)
Adipocytes express natriuretic peptide clearance receptors (NPR-C), so BNP is cleared faster and runs low. A “normal” BNP does not rule out HF in an obese patient, consider halving the cutoff (roughly 50 pg/mL). NT-proBNP is less affected.
Flash (hyperacute) pulmonary edema
In the first 1–2 hours (e.g., hypertensive flash edema) BNP has not had time to rise. A low early value does not exclude acute HF, recheck a few hours later.
HFpEF vs HFrEF
Lower ventricular wall stress in HFpEF means lower BNP for the same degree of congestion; a meaningful minority of acute HFpEF presents with near-normal BNP.
Constrictive pericarditis / tamponade
The constrained ventricle cannot stretch, so BNP stays lower than the congestion suggests. Useful discriminator: BNP is markedly lower in constrictive pericarditis than in restrictive cardiomyopathy, which helps tell the two apart.
Stable, compensated chronic HF on optimal therapy
Lower wall stress than during decompensation, BNP falls toward the patient’s “dry” baseline. Trend against that personal baseline, not a population cutoff.
Which to order: BNP vs NT-proBNP. For diagnosis and prognosis they are clinically equivalent, so most of the time you use whichever your lab runs (institutions usually stock only one).
Use NT-proBNP if the patient is on sacubitril/valsartan (ARNI, Entresto), the hard rule. Neprilysin inhibition blocks BNP breakdown so BNP is falsely elevated and uninterpretable; NT-proBNP is not a neprilysin substrate and stays valid.
NT-proBNP also has the edge for sample stability (half-life ~1–2 h vs BNP ~20 min, less minute-to-minute noise) and has well-validated age-adjusted rule-in cutoffs (>450 if <50y, >900 if 50–75, >1800 if >75).
Lean BNP in advanced CKD, both rise with renal impairment but NT-proBNP rises more (renal-only clearance), so BNP is marginally less confounded. Soft preference, both still need adjusted cutoffs.
Never compare a BNP value to an NT-proBNP value, NT-proBNP runs roughly 5–10× higher. Pick one assay and trend that same one across the admission and between visits.
BNP vs NT-proBNP, and the ARNI trap, all explained by one fact: BNP is cleared three ways (NPR-C receptor uptake, enzymatic degradation by neprilysin and other proteases, and renal excretion); NT-proBNP is cleared only by the kidney. From that single difference:
CKD raises NT-proBNP more than BNP, because the kidney is NT-proBNP’s only exit.
Obesity lowers BNP more than NT-proBNP, because NPR-C clearance acts on active BNP.
Sacubitril/valsartan (ARNI, Entresto) makes BNP go UP and become unreliable, neprilysin inhibition blocks BNP breakdown. NT-proBNP is not a neprilysin substrate, so use NT-proBNP to monitor patients on an ARNI.
Do not switch assays mid-course. Pick BNP or NT-proBNP and trend the same one, the numeric scales are not interchangeable.
⚡ Summary
Summary
Classify the Profile First
Warm or cold (perfusion) by wet or dry (congestion).Warm and wet is the great majority and is a decongestion problem.Cold and wet is cardiogenic shock and needs inotropes and perfusion pressure before diuresis.Getting this wrong is the central error: diuresing a cold patient worsens the kidney and the output.
Find What Tipped Them Over
Non-adherence with medication or diet, arrhythmia (above all new atrial fibrillation), ischemia, infection, uncontrolled hypertension, anemia, thyroid disease, and drugs (NSAIDs, steroids, non-dihydropyridine calcium channel blockers, thiazolidinediones). Treating the congestion without the trigger guarantees readmission.
IV Loop Diuretic, Adequately Dosed
Give at least 1 to 2.5 times the home oral dose, intravenously.Oral absorption is unreliable in a congested gut, which is why an outpatient dose given by mouth in hospital often does nothing. DOSE showed bolus and infusion are equivalent, and higher dosing decongests better at the cost of a transient creatinine rise.
Judge Response in Hours, Not Days
Check a urine sodium at 2 h or urine output at 6 h.A spot urine sodium below 50 to 70 mmol/L means an inadequate response, so double the dose now rather than waiting for tomorrow's weight. Serial daily weights and strict input-output remain the ward measures, but they are too slow to steer the first day.
Escalate Deliberately When Diuresis Stalls
Double the loop dose first, then add a thiazide for sequential nephron blockade (metolazone, or IV chlorothiazide for speed), giving the thiazide 30 min before the loop. Acetazolamide added early improves decongestion (ADVOR). Watch potassium, magnesium and sodium closely once combination diuretics are running, since the electrolyte losses are large and rapid.
A Creatinine Bump Is Not a Reason to Stop
A modest rise during effective decongestion reflects hemoconcentration and does not predict worse outcomes, and stopping diuresis for it leaves the patient congested, which does. Reassess volume status rather than the number, and stop when the patient is euvolemic, not when the creatinine moves.
Continue Guideline Therapy Wherever You Can
Do not routinely stop beta blockers: continue them unless the patient is in cardiogenic shock, hypotensive or severely congested, since stopping worsens outcomes. Start or continue the four pillars during the admission, which is far more effective than deferring to the outpatient setting (STRONG-HF). Come off: NSAIDs, non-dihydropyridine calcium channel blockers, thiazolidinediones, and hold the RAS inhibitor only for hypotension or acute kidney injury.
Read the BNP in Context
It is raised by wall stress, so it is also raised by atrial fibrillation, pulmonary embolism, renal failure and age.It is falsely low in obesity, where a normal value can accompany real heart failure, and in flash pulmonary edema before it has had time to rise. Sacubitril-valsartan raises BNP but not NT-proBNP, so follow NT-proBNP in those patients. Before discharge: confirm euvolemia, transition to an oral regimen for 24 h, arrange follow-up within 7 days and refer to cardiac rehabilitation.
RoundsRx Infographic Series · #35 · Cardiovascular · PDF 160 KB
Text version
ADHF, Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
ACUTE DECOMPENSATED HEART FAILURE, AT A GLANCE
🌡️ Classify: Warm/Cold × Wet/Dry. Warm-Wet = diurese. Cold-Wet = ICU + inotropes. Cold-Dry = MCS. 🧪 Workup: BNP/NT-proBNP, BMP, troponin, echo, CXR, iron studies. Identify precipitant. 💧 Diurese: IV furosemide 1–2.5× home dose. UOP goal 0.5–1 mL/kg/hr. Add metolazone if resistant. 💊 GDMT: Continue ACEi/ARNI, BB (reduce dose, don’t stop), MRA, SGLT2i. Initiate before discharge. 📈 Monitor: Daily weight, I/Os, BMP (Cr, K⁺), telemetry. Cr bump ≤0.3 acceptable during diuresis. 🏠 Discharge: Stable on PO diuretics ≥24h, at dry weight, GDMT initiated, 7-day follow-up, daily weight education.
EMERGENTCardiology
STEMI
ST-elevation myocardial infarction -complete coronary artery occlusion. Door-to-balloon < 90 minutes. Every minute of delay = more dead myocardium. This is the most time-critical diagnosis in cardiology.
🆕 2025 ACS Guideline updates apply here. Shorter DAPT with ticagrelor monotherapy after 1 month, complete revascularization for multivessel disease, intravascular imaging upgraded to Class 1, Impella CP for select cardiogenic shock, lower LDL targets post-ACS. See full 2025 changes table →
ECG Criteria
STEMI = cath lab activation. Do not delay for troponin.
Criteria
Definition
ST elevation
≥ 1 mm in ≥ 2 contiguous leads (or ≥ 2 mm in V1–V3 in men, ≥ 1.5 mm in women)
STEMI Equivalents
These patterns require emergent reperfusion even without classic ST elevation. Recognizing STEMI equivalents prevents missed cath lab activations.
Pattern
ECG Findings
Clinical Significance
New LBBB
New or presumably new LBBB in the setting of ischemic symptoms
Treat as STEMI. Use Sgarbossa criteria if prior LBBB: concordant ST elevation ≥ 1 mm (5 pts), concordant ST depression ≥ 1 mm in V1–V3 (3 pts), discordant ST elevation ≥ 5 mm (2 pts). Score ≥ 3 = MI. Modified Sgarbossa (Smith): ST/S ratio ≥ 0.25 in any lead replaces the 5 mm rule, higher sensitivity.
Posterior MI
ST depression V1–V3 with tall R waves ± upright T waves
Reciprocal changes of posterior ST elevation. Get posterior leads (V7–V9): ST elevation ≥ 0.5 mm confirms posterior STEMI. Often occurs with inferior MI (RCA/LCx). Missed in ~75% of cases on standard 12-lead.
De Winter T waves
1–3 mm upsloping ST depression at the J-point with tall, symmetric T waves in precordial leads. No ST elevation.
Proximal LAD occlusion. Present in ~2% of anterior MIs. Static pattern (does not evolve into ST elevation). Activate cath lab immediately.
Wellens syndrome
Type A (25%): Biphasic T waves (up-down) in V2–V3. Type B (75%): Deep symmetric T-wave inversions in V2–V3 (± V1–V6)
Critical proximal LAD stenosis. Occurs during pain-free intervals (T waves normalize during active ischemia). Will progress to massive anterior MI without intervention. Do NOT stress test, go to cath lab.
Hyperacute T waves
Tall, broad-based, symmetric T waves in a coronary territory. Often taller than the QRS complex.
Earliest sign of acute MI, precedes ST elevation by minutes to hours. Represents subendocardial ischemia with transmural progression. If clinical suspicion is high, serial ECGs q15–30 min or activate cath lab.
ST elevation in aVR
Diffuse ST depression in ≥ 6 leads with ST elevation in aVR (± V1)
Left main or proximal LAD occlusion, or severe 3-vessel disease. Very high mortality. Emergent cardiology consultation. Not a classic “STEMI activation” at all centers but requires urgent catheterization.
Isolated RV infarction
ST elevation in V4R (> 1 mm) with inferior ST elevation (II, III, aVF). May have ST elevation V1 with depression V2.
Proximal RCA occlusion. Preload-dependent, avoid nitrates, diuretics, morphine. Treat hypotension with IV fluid boluses. Get right-sided leads on all inferior STEMIs.
Aslanger pattern
ST elevation in lead III only (not II), with ST depression in any precordial lead, and ST elevation in V1 that does not exceed the ST depression in V6
Inferior MI with concomitant multi-vessel disease. Subtle pattern, does not meet classic STEMI criteria. Associated with worse outcomes due to multi-vessel involvement. Requires emergent angiography.
High Lateral OMI (South African Flag sign)
ST elevation in I and aVL (± V2) with reciprocal ST depression in III and aVF. ST changes may be subtle (< 1 mm) and not meet classic STEMI voltage criteria.
LCx or diagonal branch (D1) occlusion. High lateral territory is poorly represented on standard 12-lead, often missed. The “South African Flag” sign refers to the characteristic ECG morphology resembling the flag’s shape. Low voltage in limb leads makes detection harder. Have a low threshold for cath lab activation with ischemic symptoms + subtle I/aVL changes.
Coronary Territories
ECG Leads
Territory
Artery
Key Complications
V1–V4
Anterior
LAD
Largest territory. Highest mortality. LV failure, cardiogenic shock, VT/VF, anterior wall aneurysm.
II, III, aVF
Inferior
RCA (85%) or LCx (15%)
Bradycardia (AV node from RCA), RV infarct (get right-sided leads V4R). Hypotension -treat with fluids, NOT nitrates.
I, aVL, V5–V6
Lateral
LCx
Often subtle. May be missed. MR from papillary muscle ischemia.
V7–V9
Posterior
PDA (from RCA or LCx)
Missed on standard 12-lead. Always check if ST depression V1–V3.
V4R
Right ventricle
Proximal RCA
Avoid nitroglycerin, morphine, diuretics -RV is preload-dependent. Treat hypotension with IV fluids.
🚨 Management
Step-by-Step Management -STEMI
1
ABCs + IV Access + Continuous Telemetry + 12-lead ECG within 10 min Two large-bore IVs. Continuous cardiac monitoring. 12-lead ECG is the STEMI trigger -ST elevation in ≥2 contiguous leads (or new LBBB with positive Sgarbossa) confirms diagnosis. Supplemental O₂ only if SpO₂ < 90%.
🔄 Updated Practice: Old teaching: give supplemental oxygen to all MI patients. Current practice: oxygen only if SpO₂ < 90%.DETO2X-AMI, 2017 and AVOID, 2015 showed routine oxygen in normoxemic MI does NOT reduce infarct size and may worsen outcomes through coronary vasoconstriction. Hyperoxia is not benign.
Activate cath lab NOW Single phone call. Goal: door-to-balloon < 90 min. Don't wait for troponin to come back -ECG is the trigger. Notify interventionalist, OR team, and transfer team simultaneously.
4
Decide reperfusion strategy: Primary PCI vs FibrinolysisSTREAM, 2013 PCI available within 120 min → Primary PCI (gold standard). Door-to-balloon target < 90 min. Stent the culprit lesion. PCI not available within 120 min → Fibrinolysis within 30 min of first medical contact. Tenecteplase (weight-based single IV bolus) or alteplase. Transfer for angiography within 3–24h regardless (pharmacoinvasive strategy).
Fibrinolysis contraindications.Absolute: any prior ICH, ischemic stroke within 3 months, known intracranial neoplasm/AVM, suspected aortic dissection, active bleeding, significant closed head/facial trauma within 3 months. Relative: uncontrolled HTN (> 180/110), anticoagulant use, recent surgery (< 3 weeks), traumatic CPR, recent internal bleeding, pregnancy, active peptic ulcer.
5
Heparin -anticoagulation(anticoagulant) How this differs from NSTEMI: in NSTEMI, you start heparin in the ED right after the diagnosis is confirmed (the patient may not get to cath for hours, so you protect them while they wait). In STEMI, the destination is the cath lab and the wait is short (door-to-balloon < 90 min), so the heparin dose is timed to the procedure -who gives it depends on the reperfusion strategy: Primary PCI → Heparin is given in the cath lab by the interventionalist, not on the floor. UFH 70–100 units/kg IV bolus, ACT-titrated to 250–300 sec. (Why: ACT-guided dosing in the lab is precise; pre-loading on the floor complicates that titration.) Bivalirudin is an alternative (lower bleeding, slightly higher stent thrombosis). Fibrinolysis → Heparin is given immediately, as adjunct to the lytic. UFH 60 units/kg IV bolus (max 4000) → 12 units/kg/hr infusion (max 1000/hr). Target aPTT 1.5–2× control. Continue 48h or until revascularization. (Why: there's no cath lab in this scenario, so anticoagulation has to start at the time of lysis to keep the artery open.)
6
P2Y12 inhibitor -load upfront in STEMI(antiplatelet)PLATO, 2009TRITON-TIMI 38, 2007 Why STEMI gets P2Y12 upfront, NSTEMI usually defers until cath anatomy is known: In STEMI, the diagnosis is certain (ST elevation = thrombotic occlusion), the destination is certain (cath lab for primary PCI), and CABG-needing anatomy is uncommon (~3–5% of STEMIs, usually a single culprit), so pre-loading lets platelet inhibition reach therapeutic levels by the time of stent deployment. In NSTEMI/UA, ~10–15% turn out to need CABG (3-vessel disease, left main, complex anatomy); pre-loaded ticagrelor or prasugrel force a 5–7 day wait off antiplatelet before surgery, delaying revascularization and increasing in-hospital complications. ACCOAST, 2013 showed upstream prasugrel in NSTEMI did not reduce ischemic events and increased major bleeding, which is why current ACC/AHA guidelines recommend P2Y12 loading at the time of PCI in NSTEMI, not in the ED. Primary PCI → Ticagrelor 180 mg PO load (preferred) OR prasugrel 60 mg PO load (avoid prior stroke/TIA, age ≥ 75, wt < 60 kg). Clopidogrel 600 mg PO if neither tolerated. Fibrinolysis → Clopidogrel 300 mg PO load if age < 75; 75 mg PO load if age ≥ 75. CLARITY-TIMI 28, 2005 Ticagrelor and prasugrel are NOT studied with lytics -use clopidogrel.
When to add IV antiplatelet (cangrelor or GP IIb/IIIa) on top of -or instead of -oral P2Y12:
• Patient can't absorb oral P2Y12 (vomiting, intubated, post-arrest, cardiogenic shock with poor gut perfusion, NPO): use cangrelor IV (preferred -same P2Y12 class, on/off in ~1h) or GP IIb/IIIa as the bridge.
• PCI going badly (large visible thrombus, slow flow / no-reflow, distal embolization, failed reperfusion): add GP IIb/IIIa on top of the oral P2Y12 already given. Interventionalist's call.
• Cath shows CABG-needing anatomy (rare in STEMI -usually a single culprit, but possible): hold further oral P2Y12, bridge with cangrelor or short-acting GP IIb/IIIa until surgery.
• With fibrinolysis: do NOT add GP IIb/IIIa -bleeding risk too high (FINESSE killed this combination).
7
Nitroglycerin for ongoing chest pain SL NTG 0.4 mg q5 min × 3, then NTG drip 5–200 mcg/min if pain persists. ⚠️ AVOID in: RV infarct (preload-dependent -check V4R first in inferior MI), SBP < 90, PDE5 inhibitor within 24h (sildenafil) or 48h (tadalafil).
8
High-intensity statin -start within 24hPROVE IT-TIMI 22, 2004 Atorvastatin 80 mg PO (or rosuvastatin 40 mg). Start regardless of LDL -plaque stabilization + anti-inflammatory effects beyond lipid lowering. Lifelong.
9
Beta-blocker within 24h (if hemodynamically stable) Metoprolol tartrate 12.5–25 mg PO q6–12h → titrate to HR 55–65. ⚠️ Hold if: cardiogenic shock, HR < 60, SBP < 100, decompensated HF, cocaine use, severe reactive airway, high-degree AV block. COMMIT-CCS 2, 2005-early IV BB is harmful in unstable patients; oral BB once stable is the standard.
10
ACEi/ARB within 24hSAVE, 1992 Lisinopril 2.5–5 mg PO daily (or equivalent). Especially if anterior MI or EF < 40%. Prevents adverse remodeling. Hold if SBP < 100 or AKI.
11
Post-PCI / Discharge Optimization DAPT: ASA 81 mg + ticagrelor 90 mg BID (or prasugrel 10 mg daily) × 12 months minimum post-ACS DAPT Study, 2014. May shorten to 3–6 months if high bleed risk TWILIGHT, 2019. High-intensity statin lifelong 4S, 1994 Beta-blocker -continue indefinitely if EF reduced ACEi/ARB if EF < 40%, HTN, DM, or CKD Aldosterone antagonist (spironolactone or eplerenone) if EF ≤ 40% + symptomatic HF or DM EPHESUS, 2003 Smoking cessation + cardiac rehab referral
⚠️ Do NOT delay for any of these steps:
• ASA -give IMMEDIATELY on recognition
• ECG -within 10 minutes
• Cath lab activation -single phone call, don't wait for troponin
• Door-to-balloon < 90 min (primary PCI) or door-to-needle < 30 min (fibrinolysis)
Preferred over clopidogrelPLATO, 2009: reduced CV death + MI + stroke. Reversible binding. Side effects: dyspnea, bradycardia pauses (due to adenosine accumulation -ticagrelor blocks RBC ENT1 reuptake). Do NOT use with > 100 mg ASA.
Prasugrel (Effient)(antiplatelet) PREFERRED P2Y12
60 mg loading → 10 mg daily
At time of PCI
TRITON-TIMI 38, 2007: superior to clopidogrel. Contraindicated: prior stroke/TIA, age ≥ 75, weight < 60 kg (increased bleeding).
Clopidogrel (Plavix)(antiplatelet) 2ND LINE P2Y12
600 mg loading → 75 mg daily
At PCI
Use if ticagrelor/prasugrel contraindicated. Prodrug -depends on CYP2C19 metabolism. ~30% of patients are poor metabolizers (consider genetic testing).
Heparin (UFH)(anticoagulant) PCI
70–100 units/kg IV bolus (per cath lab)
At PCI
ACT-guided in cath lab. Bivalirudin is alternative (lower bleeding but higher stent thrombosis). If no PCI planned: enoxaparin 1 mg/kg SC BID is an option ESSENCE, 1997
GP IIb/IIIa inhibitor (tirofiban / Aggrastat, eptifibatide / Integrilin) (antiplatelet) BAILOUT ONLY(bailout = rescue use mid-procedure)
Tirofiban: 25 mcg/kg IV bolus → 0.15 mcg/kg/min infusion. Eptifibatide: 180 mcg/kg IV bolus → 2 mcg/kg/min infusion.
In cath lab if needed -NOT routine, NOT before cath
No longer routine in primary PCI. Reserved for cath-lab bailout: large thrombus burden, slow flow / no-reflow, distal embolization, or as a bridge when P2Y12 absorption is in doubt (vomiting, intubation). FINESSE, 2008HORIZONS-AMI, 2008 killed routine pre-cath use. Interventionalist's call.Why bailout only? Strongest antiplatelet class (blocks the final common pathway where all aggregation signals converge) but biggest bleeding risk. Modern ticagrelor/prasugrel/cangrelor + bivalirudin + DES now give ~95% of the ischemic benefit with less bleeding -marginal gain no longer worth the bleeding cost.
Especially if anterior MI or EF < 40%. Prevents remodeling. Reduce mortality SAVE, 1992.
Nitroglycerin (Nitrostat)
0.4 mg SL q5 min × 3, or drip 5–200 mcg/min
For ongoing chest pain
AVOID in: RV infarct (preload-dependent), SBP < 90, PDE5 inhibitor within 24h (sildenafil) or 48h (tadalafil). Inferior MI → check V4R first.
⚠️ Mechanical Complications
Mechanical Complications (Days 1–14)
If a STEMI patient suddenly decompensates 2–7 days post-MI → think mechanical complication.
Complication
Timing
Presentation
Diagnosis
Treatment
Ventricular free wall rupture
Day 3–7
Sudden PEA arrest, tamponade
Bedside echo → pericardial effusion
Emergent surgery. Almost always fatal without it.
Ventricular septal rupture (VSR)
Day 3–7
New harsh holosystolic murmur + acute HF
Echo with color Doppler → L-to-R shunt. O₂ step-up on right heart cath.
Surgical repair. IABP/Impella as bridge. Very high mortality.
Papillary muscle rupture
Day 2–7
New holosystolic murmur → acute severe MR → flash pulmonary edema
Echo → flail mitral leaflet, severe MR
Emergent mitral valve surgery. Afterload reduction (nitroprusside, IABP) as bridge.
LV aneurysm
Weeks–months
Persistent ST elevation post-MI, HF symptoms, arrhythmias
Echo → dyskinetic/akinetic thin-walled segment
Medical management. Anticoagulation if thrombus. Surgery if refractory arrhythmias.
📋 On Rounds
Pimp Questions
Why must you check V4R in inferior STEMI?
Inferior STEMI (II, III, aVF) is usually from RCA occlusion, and the proximal RCA also supplies the RV. Up to 40% of inferior STEMIs have RV involvement. RV infarct makes the patient preload-dependent -nitrates, morphine, and diuretics drop preload → hemodynamic collapse. V4R (right-sided V4) showing ≥ 1 mm ST elevation confirms RV involvement. Treatment: IV fluids (not nitrates), avoid diuretics, maintain preload.
What are the Sgarbossa criteria?
Used to diagnose STEMI in the presence of LBBB (where ST changes are expected). Original Sgarbossa: (1) concordant ST elevation ≥ 1 mm -most specific, (2) concordant ST depression ≥ 1 mm in V1–V3, (3) discordant ST elevation ≥ 5 mm. Modified Sgarbossa (Smith): replaces criterion 3 with ST/S ratio ≥ 25% -more sensitive. Any positive criterion in the right clinical context → activate cath lab.
Why is ticagrelor preferred over clopidogrel?
PLATO, 2009: ticagrelor reduced the composite of CV death, MI, and stroke by 16% vs clopidogrel, with 22% reduction in CV mortality. Key advantages: (1) reversible binding (clopidogrel is irreversible -platelet function recovers faster after stopping ticagrelor), (2) no CYP2C19 dependency (clopidogrel is a prodrug requiring activation -~30% are poor metabolizers). Downsides: BID dosing, dyspnea (~14%), cost.
What is the door-to-balloon time target and what happens if your hospital can't do PCI?
Door-to-balloon time target: ≤ 90 minutes at a PCI-capable hospital. If diagnosed in the field by EMS → target first medical contact-to-balloon ≤ 90 min. If your hospital is NOT PCI-capable: transfer target is first medical contact-to-balloon ≤ 120 min. If transfer time would exceed 120 min → give fibrinolytic therapy (tPA) within 30 minutes of arrival (door-to-needle ≤ 30 min) and then transfer for rescue PCI.
📣 Sample Presentation
One-Liner
"Mr. Jackson is a 58-year-old smoker with HTN presenting with acute crushing substernal chest pain radiating to left arm × 2 hours. ECG shows ST elevation in leads II, III, aVF. Taken for emergent PCI with DES to RCA with TIMI 3 flow post-intervention."
Key Points to Cover on Rounds
Cath: 99% occlusion of mid-RCA, single DES placed, TIMI 3 flow restored. Peak troponin 42 ng/mL. Echo: EF 45%, inferior hypokinesis. Medications: ASA 81 mg + ticagrelor 90 BID (DAPT), atorvastatin 80, metoprolol 25 BID, lisinopril 5 daily. No arrhythmias on telemetry. Pain-free since cath. Cardiac rehab referral placed. Plan: discharge tomorrow if stable.
Monitoring Parameters -STEMI
Parameter
Frequency
Target / Action
Continuous telemetry
Minimum 48 hours post-PCI (longer if EF ≤ 40% or arrhythmias)
Watch for reperfusion arrhythmias (AIVR -usually benign, VT/VF, bradycardia in inferior MI). AIVR is a sign of successful reperfusion -do not treat unless hemodynamically unstable.
Serial troponins
q3-6h until peak identified (typically 12-24h post-PCI)
Peak troponin correlates with infarct size. Rising troponin after initial decline → stent thrombosis or reinfarction.
ECG
Immediately post-PCI, then daily × 2-3 days
ST resolution > 50% within 60-90 min post-PCI = successful reperfusion. New ST changes → concern for stent thrombosis, re-occlusion.
BP and HR
q1h × 4h post-cath, then q4h
SBP > 90 for ACEI/BB initiation. HR 60-80. Hypotension in inferior MI → suspect RV infarct (give fluids, avoid nitroglycerin).
EF, wall motion, mechanical complications (VSD -new murmur + hemodynamic collapse; papillary muscle rupture -acute MR). Repeat at 6-12 weeks if EF ≤ 40%.
Post-STEMI DAPT is critical. Educate patients: do NOT stop aspirin or ticagrelor/prasugrel without cardiology approval. Premature discontinuation within 30 days of DES = highest risk period for stent thrombosis.
🧪 Workup
Diagnostic Evaluation -STEMI
Do NOT delay reperfusion for labs. Door-to-balloon goal < 90 min (PCI) or door-to-needle < 30 min (fibrinolytics). Draw labs while activating the cath lab.
Test
Rationale
Key Values
12-lead ECG
Diagnose STEMI. Identify culprit territory. Repeat q15 min if evolving or diagnostic uncertainty.
≥ 1 mm ST elevation in 2 contiguous leads (≥ 2 mm in V1-V3 for men > 40). New LBBB with ischemic symptoms. Right-sided leads (V4R) for inferior STEMI → RV involvement.
Serial troponins
Confirm myocardial injury and trend infarct size. Do NOT wait for troponin to activate cath lab in STEMI.
Draw at presentation, then q3-6h × 3. Peak troponin correlates with infarct size. High-sensitivity troponin (hs-cTnI or hs-cTnT).
CBC
Baseline Hgb (bleeding risk with anticoagulation/DAPT), platelets (for P2Y12 inhibitor).
Hgb < 10 = higher bleeding risk with aggressive antithrombotics. Plt < 100K = relative contraindication to DAPT.
Obtain within 24-48h post-PCI. EF ≤ 40% → ACEI/ARB + aldosterone antagonist. New MR → papillary muscle dysfunction.
Type and screen
In case of bleeding complication or need for emergent surgery.
Standard pre-procedural lab.
🏥 Clinical Cases
Case 1: Classic Anterior STEMI -The Textbook Case
Scenario: 58M, smoker, HTN, presents to ED at 2:14 AM with crushing substernal chest pain radiating to left arm × 40 minutes. Diaphoretic, pale, HR 102, BP 148/92.
Phase
Time
Action
Rationale / Pearl
ED Arrival
T+0 min
12-lead ECG within 10 minutes
ECG shows ST elevation V1-V4 with reciprocal ST depression in II, III, aVF. This is an anterior STEMI -LAD territory. Activate cath lab immediately.
Chew ASA for rapid absorption. Load P2Y12 inhibitor before cath. Heparin for anticoagulation during PCI. Statin started day 1 regardless of lipid panel.
Door-to-balloon = 48 min (goal < 90 min). Complete occlusion confirmed -this is why ECG, not troponin, drives the decision. Troponin was still negative at arrival.
Troponin #1
T+0 (arrival)
hs-cTnI: 45 ng/L (normal < 26)
Only mildly elevated at presentation -do not wait for troponin to confirm STEMI. ECG is the decision tool. Early troponin may be falsely reassuring in early presenters.
Large delta = large infarct. Rapid rise-and-fall pattern typical of reperfused STEMI. Expected to peak 12-24h post-onset.
Troponin #3
T+6h
hs-cTnI: 38,600 ng/L. Still rising.
Continue trending q6h. The magnitude of peak predicts LV dysfunction severity and 30-day mortality. > 10,000 ng/L in anterior STEMI = high risk for EF < 40%.
Peak troponin reached ~12h post-symptom onset. Large anterior MI confirmed. Correlates with TTE findings. Subsequent decline = no re-occlusion. Any secondary rise → suspect stent thrombosis.
CCU Day 1
T+3h
Chest pain resolved. Troponin peaks at 85 ng/mL. TTE: EF 40%, anterior wall hypokinesis.
Peak troponin correlates with infarct size. EF 40% -will need ACEi/ARB and assess for ICD at 40 days. Start metoprolol 25 mg BID if hemodynamically stable.
Declining troponin = reassuring (no re-occlusion). ACEi started for EF ≤ 40% (reduces remodeling and mortality). BB reduces arrhythmia risk. Early rehab referral improves adherence and outcomes.
Ensure all 4 pillars prescribed before discharge. LDL goal < 70 (or < 55 per ESC). Repeat TTE in 6-12 weeks. Discuss ICD if EF still ≤ 35% at 40 days.
Teaching point: Anterior STEMIs have the worst prognosis because the LAD supplies ~40% of LV myocardium. These patients are most likely to develop systolic HF, and rapid reperfusion is critical.
Case 2: Inferior STEMI with RV Involvement -The Fluid-Dependent Patient
Scenario: 72M, DM2 and dyslipidemia, presents with epigastric pain and nausea × 1 hour. Thought it was indigestion. HR 48, BP 82/54. Diaphoretic.
Phase
Time
Action
Rationale / Pearl
ED Arrival
T+0
ECG: ST elevation II, III, aVF. Reciprocal depression I, aVL.
Inferior STEMI -RCA territory (85%). Immediately get right-sided leads (V4R). V4R shows ST elevation ≥ 1mm -confirms RV infarct.
Critical Decision
T+3 min
NO nitroglycerin. NO morphine. Start 500 mL NS bolus.
RV infarct = preload dependent. Nitrates and morphine drop preload → cardiovascular collapse. Fluids first. If still hypotensive after 1-2L, start dobutamine (not norepinephrine -need inotropy, not vasoconstriction).
Meds
T+8 min
ASA 325 + clopidogrel 600 (not ticagrelor -patient is bradycardic). Heparin. Atropine 0.5 mg IV for symptomatic bradycardia.
Ticagrelor can worsen bradycardia (PLATO showed more bradycardic pauses). Clopidogrel is safer here. Atropine for vagally-mediated bradycardia (common in inferior MI due to RCA supplying AV node).
Cath Lab
T+62 min
PCI to RCA: 100% mid-vessel occlusion. DES placed. TIMI 3 flow. BP improves to 106/68.
RCA reperfusion often dramatically improves hemodynamics. Bradycardia may resolve as AV node perfusion returns. If persistent complete heart block → temporary pacer.
Troponin #1
T+0 (arrival)
hs-cTnI: 180 ng/L (elevated > 26)
Elevated at presentation -1 hour of symptoms means troponin is already rising. In inferior STEMI, absolute values tend to be lower than anterior (smaller territory). Still -do NOT wait for troponin result.
Troponin #2
T+3h
hs-cTnI: 5,800 ng/L. Rising.
Moderate elevation consistent with RCA territory (supplies ~25-30% of LV). Compare: LAD occlusion often produces troponins > 50,000.
Troponin #3 (peak)
T+8h
hs-cTnI: 14,200 ng/L (peak).
Earlier peak than anterior STEMI (smaller territory = faster washout post-reperfusion). Declining troponin + improving hemodynamics = successful reperfusion. Any secondary rise → re-occlusion or stent thrombosis.
CCU Day 1
T+6h
Sinus rhythm restored, HR 68. BP 110/72 on 150 mL/hr NS. TTE: EF 50%, inferior hypokinesis, RV dilated but improving. Troponin trending down.
RV function often recovers within days-weeks (RV is more resilient than LV). Avoid diuretics -patient needs volume. Hold ACEi until hemodynamically stable.
RV infarct patients are exquisitely sensitive to volume depletion AND afterload reduction. Titrate meds slowly. If EF preserved, ACEi is less urgent but still beneficial.
Key teaching: Always check V4R in inferior STEMI. RV infarct changes your entire management -no nitrates, aggressive fluids, be cautious with preload-reducing drugs.
Teaching point: Diabetic patients often present atypically -epigastric pain, nausea, or just "not feeling right." Low threshold for ECG in any diabetic with GI complaints.
Case 3: Late Presenter with Cardiogenic Shock -The Nightmare Scenario
Scenario: 65F, no prior medical history, arrives by EMS after 6 hours of chest pain that started during sleep. She delayed calling because she thought it was anxiety. HR 118, BP 76/50, SpO2 89%, cold/clammy extremities, JVD.
Phase
Time
Action
Rationale / Pearl
ED Arrival
T+0
ECG: ST elevation V1-V6, I, aVL (massive anterolateral). Chest X-ray: bilateral pulmonary edema.
Extensive anterior STEMI with Killip Class IV (cardiogenic shock). This is the highest-risk presentation -mortality 40-50% even with PCI. Do NOT delay cath for stabilization.
Cardiogenic shock = primary PCI regardless of time from onset. Norepinephrine is first-line vasopressor in cardiogenic shock (SOAP II trial). Avoid dopamine (more arrhythmias). Load P2Y12 via NG if vomiting.
Pre-Cath
T+15 min
Intubated for respiratory failure and impaired consciousness. PA catheter placed: CI 1.6, PCWP 28, SVR 1800.
PA catheter confirms cardiogenic shock: low CI (< 2.2), high PCWP (> 18), high SVR. BiPAP is an alternative if patient is alert, but this patient is deteriorating.
Cath Lab
T+55 min
PCI to LAD: 100% proximal occlusion. DES placed. TIMI 2 flow (incomplete reperfusion). Intra-aortic balloon pump (IABP) placed.
TIMI 2 flow (partial) has worse prognosis than TIMI 3 (complete). Mechanical circulatory support (IABP or Impella) considered for refractory shock. IABP-SHOCK II showed no mortality benefit for IABP, but still used as bridge.
Troponin #1
T+0 (arrival)
hs-cTnI: 28,400 ng/L (massively elevated)
Already very high at presentation -6 hours of unreperfused ischemia. In cardiogenic shock, troponin may be falsely lower due to decreased cardiac output (poor washout). Once reperfused, expect a secondary surge.
Reperfusion washout phenomenon: troponin spikes after PCI as necrotic myocardium is reperfused and cellular contents flood the circulation. Higher post-PCI spike = more necrosis, not a new event.
Troponin #3
T+12h
hs-cTnI: 142,000 ng/L (peak).
Late presenters (6h+) have the highest peak troponins. TIMI 2 flow means incomplete washout -troponin may plateau longer. This level predicts severe LV dysfunction and high 30-day mortality.
Troponin #4
T+24h
hs-cTnI: 98,000 ng/L. Beginning to decline.
Slow decline expected with TIMI 2 flow. If troponin re-rises → stent thrombosis, extension of infarct, or type 2 MI from shock. Recheck ECG immediately.
CCU Day 1-2
Persistent shock on norepi + dobutamine. TTE: EF 15%, diffuse anterior akinesis. Lactate trending down from 6.8 to 3.1. Cr rising (1.1 → 2.3). Troponin 98,000 → 54,000 ng/L.
Multiorgan dysfunction from prolonged cardiogenic shock. Add milrinone if dobutamine insufficient. Avoid aggressive diuresis -cardiorenal syndrome. Consider Impella if failing IABP.
Day 3-5
Slowly weaning vasopressors. Extubated Day 4. Watch for mechanical complications (VSD, papillary rupture -classically Day 3-7).
Day 3-7 is the danger zone for mechanical complications. New murmur + hemodynamic collapse = STAT TTE. Free wall rupture presents as sudden PEA arrest with tamponade.
Day 7-10
Off pressors. EF 20% on repeat TTE. Start captopril 6.25 mg TID (short-acting, easy to titrate). Careful diuresis with IV furosemide.
Use short-acting ACEi (captopril) initially -if BP drops, it wears off in hours. Sacubitril/valsartan NOT in acute phase (< 36h post-MI). Start after stabilization.
Discharge (Day 14)
ASA 81 + clopidogrel 75 × 12 months. Carvedilol 3.125 BID. Captopril 12.5 TID (switch to sacubitril/valsartan outpatient). Atorvastatin 80. Eplerenone 25 mg. Furosemide PRN. LifeVest (wearable defibrillator) until 40-day EF reassessment for ICD.
EF 20% → high SCD risk. LifeVest bridges to 40-day reassessment (don't implant ICD immediately -EF may recover). If EF still ≤ 35% at 40 days → ICD. Refer for advanced HF evaluation if no recovery.
Teaching point: Women present later, have atypical symptoms more often, and have higher mortality from STEMI than men. Always maintain high suspicion for ACS in women with chest, jaw, back, or epigastric pain.
Case 4: Posterior STEMI -The One You Almost Missed
Scenario: 49M, no known PMH, presents with 2 hours of severe interscapular and chest pressure. HR 78, BP 134/82. Initial ECG looks "normal" to the intern.
Phase
Time
Action
Rationale / Pearl
ED Arrival
T+0
ECG: No ST elevation. But -ST depression V1-V3, tall R waves in V1-V2 (R/S ratio > 1). Subtle but there.
This IS a STEMI. ST depression V1-V3 with tall R waves = posterior MI (mirror image). The standard 12-lead has NO posterior-facing leads. This is the most commonly missed STEMI.
Key Move
T+5 min
Posterior leads V7-V9. V7-V9 show ST elevation ≥ 0.5 mm.
Posterior STEMI confirmed. This is a STEMI equivalent -activate cath lab immediately. LCx or PDA (from RCA) territory. Any ST elevation ≥ 0.5 mm in posterior leads is diagnostic.
Standard STEMI protocol. Do NOT wait for troponin to confirm. The posterior leads are your proof.
Cath Lab
T+72 min
PCI to LCx: 100% mid-vessel occlusion. DES placed. TIMI 3 flow.
LCx occlusion confirmed. Door-to-balloon 72 min. Without posterior leads, this patient would have been admitted as "NSTEMI" and waited hours-days for cath.
Troponin #1
T+0 (arrival)
hs-cTnI: 620 ng/L (elevated)
2 hours of symptoms -troponin already elevated. In posterior STEMI, the ECG may look "normal" but the troponin confirms myocardial injury. However the posterior leads, NOT the troponin, drove the cath lab activation.
Troponin #2
T+3h
hs-cTnI: 4,200 ng/L. Rising.
LCx territory is smaller than LAD -expect moderate (not massive) troponin elevation. Peak troponins in LCx STEMI are typically 5,000-25,000 ng/L range.
Troponin #3 (peak)
T+8h
hs-cTnI: 9,800 ng/L (peak).
Moderate peak -consistent with smaller infarct territory and good TIMI 3 reperfusion. Early reperfusion limits infarct size. Declining troponin + preserved EF = excellent prognosis.
Good EF because LCx territory is smaller than LAD. Mild MR from posterior papillary muscle -monitor with serial TTE. Usually improves with reperfusion.
Key teaching: "Normal" ECG + ACS symptoms → get posterior leads. ST depression V1-V3 is never normal in ACS. This diagnosis is made by the physician who thinks of it, not by the ECG machine's algorithm.
Teaching point: Train yourself to look at V1-V3 for ST depression in every ACS patient. If you see it, say "posterior leads" out loud. The ECG machine will never auto-read "posterior STEMI" -only you will.
Case 5: Young Patient with Cocaine-Induced STEMI -The Trap
Scenario: 32M, no PMH, presents at 1 AM with chest pain after using cocaine 2 hours ago. HR 112, BP 168/104, agitated. ECG: ST elevation V1-V4.
Phase
Time
Action
Rationale / Pearl
ED Arrival
T+0
ECG: ST elevation V1-V4. STEMI criteria met. But -is this true coronary occlusion or cocaine-induced vasospasm?
Doesn't matter initially -treat as STEMI. Activate cath lab. Can distinguish at angiography. 6% of cocaine chest pain has real MI.
Critical Meds
T+3 min
ASA 325 mg. Benzodiazepine (diazepam 5-10 mg IV). Nitroglycerin 0.4 mg SL. NO BETA-BLOCKERS.
Beta-blockers are CONTRAINDICATED in cocaine MI -causes unopposed alpha stimulation → worsens coronary vasospasm and hypertension. Benzos reduce sympathetic drive. Nitro treats vasospasm. If nitro + benzo resolve ST elevation → likely vasospasm, not thrombotic occlusion.
Response
T+15 min
After diazepam + nitro: ST elevation persists. Pain ongoing. → Proceed to cath lab.
If ST changes resolve with benzos + nitro → observe, serial ECGs, troponins. If ST changes persist → angiography. This patient has persistent ST elevation → real occlusion until proven otherwise.
Cath Lab
T+58 min
PCI to LAD: Thrombus with 90% stenosis in a young vessel. Aspiration thrombectomy + DES. TIMI 3 flow.
Cocaine causes MI via: (1) coronary vasospasm, (2) accelerated atherosclerosis, (3) increased platelet aggregation, (4) increased myocardial oxygen demand. This patient had both thrombus AND underlying disease.
Troponin #1
T+0 (arrival)
hs-cTnI: 52 ng/L (mildly elevated)
Only mildly elevated -cocaine was used 2h ago, but coronary occlusion may be more recent. Key point: if ST elevation resolves with benzos + nitro AND troponin is normal → vasospasm. If troponin rises → true infarction regardless of vasospasm resolution.
Rising troponin confirms true MI -not just vasospasm. Cocaine-induced MI can have both components (spasm + thrombus). The delta (52 → 6,800) confirms acute necrosis.
Troponin #3 (peak)
T+8h
hs-cTnI: 18,400 ng/L (peak).
Moderate peak -aspiration thrombectomy + early reperfusion limited infarct size. Young vessels with less collateral disease may paradoxically have larger infarcts (no collateral protection). Monitor for decline.
CCU Day 1
Symptom free. Troponin declining: 11,200 ng/L. TTE: EF 50%. Start amlodipine 5 mg (vasodilator, safe in cocaine). Still no beta-blocker.
CCB (amlodipine or diltiazem) is safe and treats both vasospasm and hypertension. Can consider non-selective BB (carvedilol) only after cocaine fully cleared (24-48h) and only if clear cardiac indication.
Discharge prescription without addressing cocaine use = guaranteed readmission. Substance abuse consult is as important as the stent. Document the conversation. Arrange follow-up.
Teaching point: The boards love this case. Remember: no beta-blockers with cocaine. Benzos + nitro first. And always address the substance use -it's the modifiable risk factor that will kill this patient.
⚡ Summary
Summary
Diagnose in the First 10 Minutes
ECG within 10 minutes of arrival.ST elevation of 1 mm or more in 2 contiguous leads (2 mm in V2-V3 for men under 40, 2.5 mm for men over 40, 1.5 mm for women), or a new LBBB with the Sgarbossa criteria.Do not wait for the troponin: it is normal early, and the ECG plus the story is the whole diagnosis.
Recognize the STEMI Equivalents
Occlusion without classic ST elevation: de Winter T waves, hyperacute T waves, Wellens syndrome, posterior MI, ST elevation in aVR with diffuse depression, high lateral OMI (South African flag sign) and the Aslanger pattern.All of these mean emergent reperfusion.Get posterior leads (V7 to V9) for ST depression in V1 to V3, and right-sided leads (V4R) for inferior infarcts.
Reperfuse Against the Clock
Door-to-balloon under 90 minutes at a PCI center, under 120 minutes if transferring.If that is unachievable, give fibrinolysis within 30 minutes of arrival, then transfer for angiography in 3 to 24 h (a pharmaco-invasive strategy). Activate the cath lab from the field on a prehospital ECG.Every 30-minute delay raises 1-year mortality by about 7.5%.
Give the Drugs That Matter
Aspirin 325 mg chewed (chewed for faster absorption). A P2Y12 inhibitor, ticagrelor or prasugrel preferred over clopidogrel; prasugrel is contraindicated after stroke or TIA. Anticoagulation with heparin or bivalirudin. High-intensity statin.Beta blocker within 24 h once stable, and not while the patient is in heart failure, hypotensive or bradycardic.
MONA Is Dead
Morphine may increase mortality, because it delays and blunts oral antiplatelet absorption, so use it only for refractory pain. Oxygen only if SpO₂ is below 90%: routine oxygen in a normoxic patient increases infarct size. Nitrates are symptomatic only, and are contraindicated in right ventricular infarct, hypotension and recent PDE5 inhibitor use.
Inferior STEMI: Check the Right Ventricle Before Nitrates
Get V4R in every inferior STEMI.RV infarct is preload-dependent, so nitrates and diuretics cause profound hypotension, and the treatment is fluid loading plus reperfusion. Inferior infarcts also cause bradycardia and heart block, so have atropine and pacing available.
Watch for the Mechanical Complications
Days 1 to 14: papillary muscle rupture with acute mitral regurgitation and flash pulmonary edema (a new murmur may be soft or absent), ventricular septal rupture with a harsh holosystolic murmur and a thrill, and free wall rupture with tamponade and sudden electromechanical dissociation. All three are surgical emergencies, and a late presenter who was never reperfused is the classic patient.
Know the Traps
Cocaine-associated STEMI: avoid beta blockers, which leave unopposed alpha stimulation and worsen the vasospasm; use benzodiazepines, nitrates and calcium channel blockers. Posterior MI is the one that gets missed: ST depression in V1 to V3 with tall R waves is a posterior injury current, not anterior ischemia. Cardiogenic shock means emergent PCI plus consideration of mechanical support, and it carries the highest mortality of any STEMI presentation. Every discharge gets the ABCDE package plus cardiac rehabilitation.
Acute coronary syndrome WITHOUT ST elevation. Partial or intermittent coronary occlusion. Risk-stratify early (TIMI, GRACE, HEART) to determine invasive vs conservative strategy. Unlike STEMI, you have time to think -but not too much.
Risk-stratify. May be managed conservatively if low-risk.
With high-sensitivity troponin assays, true "unstable angina" is increasingly rare. Most patients with ACS symptoms now have detectable troponin elevation.
Risk Stratification -HEART Score -ED chest pain disposition (discharge vs admit vs cath)
Best for ED chest pain disposition -identifies low-risk patients safe for early discharge vs those needing admission and workup. HEART Pathway, 2015
Component
0 Points
1 Point
2 Points
H -History
Non-suspicious
Moderately suspicious
Highly suspicious
E -ECG
Normal
Non-specific repolarization changes
Significant ST deviation
A -Age
< 45
45–64
≥ 65
R -Risk factors
None
1–2 factors
≥ 3 factors or known CAD
T -Troponin
Normal
1–3× ULN
> 3× ULN
Score
Risk
Action
0–3
Low (< 2% MACE at 6 weeks)
Consider early discharge with outpatient follow-up. Stress test if needed.
4–6
Intermediate
Admit, observe, serial troponins. Consider angiography.
7–10
High (> 50% MACE)
Early invasive strategy -angiography within 24h.
TIMI Risk Score for UA/NSTEMI -14-day risk of death, MI, or urgent revascularization
Quick bedside risk stratification -7 yes/no questions, 1 point each. Higher score = higher risk of adverse events at 14 days. TIMI 11B, 1998
Variable
1 Point If Present
Age ≥ 65
Yes / No
≥ 3 CAD risk factors
HTN, DM, dyslipidemia, smoking, family hx of premature CAD
Known CAD (stenosis ≥ 50%)
Prior coronary stenosis ≥ 50% on cath
ASA use in past 7 days
Suggests breakthrough event despite aspirin
≥ 2 anginal episodes in 24h
Recurrent ischemia = higher risk
ST deviation ≥ 0.5 mm
ST depression or transient ST elevation on ECG
Elevated cardiac biomarkers
Troponin or CK-MB above upper limit of normal
TIMI Score
14-Day Event Rate
Risk Level
Action
0–2
4.7%
Low
Conservative management. Consider early discharge if HEART score also low.
3–4
13.2%
Intermediate
Admit. Consider angiography within 24–72h.
5–7
40.9%
High
Early invasive strategy -cath within 24h. Consider ICU-level monitoring.
TIMI vs HEART vs GRACE: TIMI is quick and easy at bedside (7 yes/no questions). HEART is best validated for ED chest pain disposition (who goes home vs who gets admitted). GRACE is the most accurate mortality predictor and drives invasive strategy timing (GRACE > 140 → cath within 24h). Use GRACE for admitted NSTEMI patients.
GRACE Score (Global Registry of Acute Coronary Events) -in-hospital and 6-month mortality after ACS, guides invasive timing
Most accurate predictor of in-hospital and 6-month mortality in ACS -used to determine timing of invasive strategy in admitted NSTEMI patients.
Variable
Details
Age
Continuous -higher age = more points (e.g., 60 yo = ~58 pts, 80 yo = ~91 pts)
Nitroglycerin for ongoing chest pain SL NTG 0.4 mg q5min × 3, then NTG drip 5–200 mcg/min if pain persists. ⚠️ Contraindications: SBP < 90, RV infarct (check right-sided ECG), PDE5 inhibitor within 24–48h.
4
Anticoagulation -start heparin(anticoagulant) Give to all NSTE-ACS unless contraindicated (active bleeding, recent ICH, known HIT). Risk scores guide cath timing, NOT the decision to anticoagulate. UFH drip: 60 U/kg bolus (max 4,000) → 12 U/kg/hr (max 1,000). Target aPTT 1.5–2.5× control. OR Enoxaparin: 1 mg/kg SC BID (if no PCI planned within 24h, CrCl > 30) ESSENCE, 1997 ⚠️ Do NOT switch between heparin types (increases bleeding risk).
5
Risk stratify -TIMI + HEART + GRACE + serial troponins TIMI scoreQuick bedside -7 yes/no questions, 1 point each. Predicts 14-day death/MI/urgent revasc. Fast to calculate at the bedside; higher score = more benefit from early invasive strategy. TIMI 11B, 1998 HEART scoreED disposition -best for deciding who goes home vs who gets admitted. 0–3 = low risk (< 2% MACE), safe for early discharge with outpatient follow-up. GRACE scoreMost accurate mortality prediction -in-hospital and 6-month mortality. Drives invasive strategy timing: GRACE > 140 = cath within 24h. Use for all admitted NSTEMI patients. Serial troponins q3–6h -watch for rise and/or fall pattern.
6
Decide: Invasive vs Conservative StrategyTIMACS, 2009 GRACE > 140 or high-risk features → Early invasive (cath within 24h) GRACE 109–140 (intermediate risk) → Delayed invasive (cath within 24–72h) GRACE ≤ 108, negative troponins, no high-risk features → Conservative. Stress test if needed.
This is essentially a STEMI-equivalent presentation without ST elevation.
Early invasive (≤ 24h)
GRACE > 140, rising troponin, new ST changes, dynamic ECG changes
Cath within 24h
TIMACS, 2009: early (< 24h) vs delayed (> 36h) → reduced refractory ischemia in high-risk patients (GRACE > 140).
Delayed invasive (24–72h)
GRACE 109–140, intermediate risk (e.g., diabetes, EF < 40%, post-MI angina, prior PCI/CABG, GFR < 60)
Cath within 72h
Acceptable for stable patients. Load P2Y12 when anatomy known (cath lab).
Conservative / ischemia-guided
GRACE ≤ 108, no recurrent symptoms, negative serial troponins, no high-risk features
Stress test if needed
Medical management. Cath only if stress test positive or recurrent symptoms.
7
P2Y12 inhibitor -timing depends on strategy(antiplatelet)PLATO, 2009TRITON-TIMI 38, 2007 Going to cath → Load in the cath lab AFTER coronary anatomy is known (preserves CABG option -ticagrelor/clopidogrel delay surgery 5–7 days). Conservative strategy → Load upfront (ticagrelor 180 mg or clopidogrel 600 mg). Preferred: Ticagrelor 90 mg BID (reversible, faster onset, no CYP2C19 resistance). Prasugrel if going to PCI and no contraindications (prior stroke/TIA, age ≥75, wt <60 kg).
Agent
Loading
Maintenance
Mechanism
Notes
Ticagrelor (Brilinta) PREFERRED
180 mg PO
90 mg BID
Reversible
Faster onset, no CYP2C19 issue. Side effects: dyspnea, bradycardia (adenosine accumulation -blocks RBC ENT1 reuptake). Do NOT use with ASA > 100 mg.
Prasugrel (Effient)
60 mg PO
10 mg daily
Irreversible
Only after anatomy known (PCI confirmed). Contraindicated: prior stroke/TIA. Avoid: age ≥ 75, wt < 60 kg.
Clopidogrel (Plavix) 2ND LINE
600 mg PO
75 mg daily
Irreversible (prodrug)
Use if ticagrelor/prasugrel contraindicated. ~30% of patients are CYP2C19 poor metabolizers (consider genetic testing).
Cangrelor (Kengreal) IV OPTION
30 mcg/kg IV bolus
4 mcg/kg/min infusion
Reversible (IV)
For cath lab if patient can't take PO or needs immediate platelet inhibition. Bridge until oral P2Y12 onset.
Pre-treatment controversy in NSTEMI.ACCOAST, 2013 showed prasugrel pre-treatment before angiography provided no ischemic benefit but INCREASED bleeding. Current ESC guidance: do NOT routinely pre-treat with P2Y12 if early invasive strategy is planned -load in the cath lab once anatomy is known. STEMI is different (load upfront because diagnosis is certain).
GP IIb/IIIa inhibitors (tirofiban / Aggrastat, eptifibatide / Integrilin) (antiplatelet -bailout = rescue use mid-procedure) Bailout role only: high thrombus burden, slow flow / no-reflow, or bridge when P2Y12 absorption is in doubt (vomiting, intubation). EARLY ACS, 2009 showed pre-cath use adds bleeding without benefit. Why bailout only? Strongest antiplatelet class (blocks final common pathway) but biggest bleeding risk -modern P2Y12 + bivalirudin + DES deliver ~95% of the ischemic benefit with less bleeding.
PCI vs CABG vs Medical Therapy:
• Stable CAD: PCI does NOT beat optimal medical therapy on hard outcomes COURAGE, 2007
• Multivessel / left-main: CABG preferred for complex anatomy SYNTAX, 2009
• Diabetics with multivessel CAD: CABG beats PCI FREEDOM, 2012
If CABG is needed: hold oral P2Y12 (clopidogrel 5d, ticagrelor 3d, prasugrel 7d), continue ASA. If antiplatelet protection still needed, bridge with cangrelor (preferred -IV P2Y12, off in ~1h) or short-acting GP IIb/IIIa (tirofiban / eptifibatide, off in 2–4h). This is why P2Y12 is loaded in the cath lab, not before -pre-loading forces a 5–7 day surgical delay if anatomy turns out to need CABG.
8
High-intensity statin -start within 24hPROVE IT-TIMI 22, 2004 Atorvastatin 80 mg PO (or rosuvastatin 40 mg). Start regardless of LDL -plaque stabilization + anti-inflammatory effects beyond lipid lowering. Lifelong.
9
Beta-blocker within 24 hours (if hemodynamically stable) Metoprolol tartrate 12.5–25 mg PO q6–12h → titrate to HR 55–65. ⚠️ Hold if: SBP < 100, HR < 60, active HF/pulmonary edema, cocaine use, high-degree AV block. Defer until after the invasive/conservative decision and hemodynamic status is clear -BB is not emergent.
10
Post-PCI / Discharge Optimization DAPT: ASA 81 mg + ticagrelor 90 mg BID × 12 months (minimum 6 months if high bleed risk) PLATO, 2009 High-intensity statin lifelong 4S, 1994 Beta-blocker (continue indefinitely if EF reduced) ACEi/ARB if EF < 40%, HTN, DM, or CKD Smoking cessation + cardiac rehab referral
⚠️ Do NOT delay for any of these steps:
• Aspirin -give IMMEDIATELY on recognition
• ECG -within 10 minutes
• Heparin -start as soon as NSTEMI/UA diagnosis confirmed (STEMI primary PCI = give in cath lab; STEMI lytic = give as adjunct in the ED)
• Cath -within 2h if hemodynamically unstable (treat like STEMI)
📋 On Rounds
Pimp Questions
Why delay P2Y12 loading until cath in NSTEMI?
~10–15% of NSTEMI patients have left main or severe three-vessel disease requiring CABGSYNTAX, 2009FREEDOM, 2012. If you load ticagrelor or clopidogrel before knowing the anatomy, the patient must wait 5–7 days for the drug to wash out before safe surgery (bleeding risk). By waiting to load until coronary anatomy is known in the cath lab, you preserve the option for urgent CABG without delay.
What's the HEART score and how does it guide disposition?
HEART = History, ECG, Age, Risk factors, Troponin. Score 0–10. 0–3 = low risk (< 2% MACE at 6 weeks) → safe for early discharge with outpatient follow-up. 4–6 = intermediate → admit, observe, serial troponins, consider cath. 7–10 = high risk (> 50% MACE) → early invasive strategy within 24h. The HEART score has been validated in multiple large studies and is increasingly used over TIMI for ED chest pain evaluation.
When do you choose early invasive (cath within 24h) vs conservative strategy in NSTEMI?
Early invasive (cath within 24h): GRACE score > 140, troponin rise, dynamic ST changes, hemodynamic instability, recurrent angina despite therapy, diabetes, eGFR < 60, prior CABG/PCI, LVEF < 40%. Conservative (medical therapy, stress test before cath): low GRACE score, no dynamic changes, troponin borderline, low-risk features. TIMACS, 2009: early intervention (within 24h)
What anticoagulation do you start in NSTEMI and when do you stop it?
Unfractionated heparin drip (60 U/kg bolus → 12 U/kg/hr, target aPTT 1.5-2.5× control) or enoxaparin 1 mg/kg SC BID (if not going to cath immediately). Continue until cath/PCI or for 48h if conservative strategy. Fondaparinux 2.5 mg SC daily is an alternative with lowest bleeding risk but needs UFH supplementation at cath. Key: don't switch between heparin types (increases bleeding risk).
Case 1: Type 1 NSTEMI, Classic Presentation
62M with HTN, DM2, and 40-pack-year smoking history presents with substernal chest pressure radiating to the left arm for 2 hours, associated with diaphoresis and nausea. Vitals: BP 158/92, HR 88, SpO2 96%. ECG shows ST depressions in V4-V6 with T-wave inversions in I and aVL. Troponin trending 0.4 → 1.8 → 3.2 ng/mL. HEART score 8 (high risk).
Management:Aspirin 325 mg chewed immediately, heparin drip (60 U/kg bolus → 12 U/kg/hr), atorvastatin 80 mg, metoprolol tartrate 12.5 mg PO BID. GRACE score 148, early invasive strategy, cath within 24 hours. P2Y12 inhibitor loading deferred until coronary anatomy known in the cath lab to preserve CABG option. NTG SL PRN for recurrent chest pain.
Case 2: Type 2 NSTEMI, Demand Ischemia
78F admitted for community-acquired pneumonia, found to have troponin mildly elevated at 0.12 → 0.18 → 0.14 ng/mL (rising then trending down). HR 112 on admission, now improving to 88 with IV fluids and antibiotics. ECG shows sinus tachycardia with nonspecific T-wave flattening, no ST depressions or dynamic changes. No chest pain, troponin was drawn as part of sepsis workup.
Management: This is Type 2 MI (demand ischemia), tachycardia and hypoxemia from pneumonia caused supply-demand mismatch, not plaque rupture. Treat the underlying pneumonia, not with cath. Avoid aggressive anticoagulation or invasive strategy. Start atorvastatin 80 mg for secondary prevention. Cardiology consult for outpatient stress test after pneumonia resolves. Serial troponins to confirm downtrend.
Case 3: High-Risk NSTEMI with Cardiogenic Shock
55M with no prior cardiac history presents with acute dyspnea, diaphoresis, and chest tightness for 6 hours. Vitals: BP 82/54, HR 118, SpO2 88% on 4L NC. Exam reveals bilateral crackles, elevated JVP, cool extremities. ECG shows diffuse ST depressions with TWI in V1-V4 and reciprocal changes. Troponin 8.6 ng/mL. Bedside echo: EF 30%, diffuse hypokinesis. Killip class IV.
Management: This is NSTEMI with cardiogenic shock, treat as STEMI equivalent. Emergent cath (< 2 hours). Start norepinephrine for hemodynamic support (avoid dobutamine alone if SBP < 90). Consider IABP or Impella for mechanical circulatory support. Cath reveals multivessel disease, culprit PCI now, then heart team discussion for staged PCI vs CABG for remaining lesions. Hold beta-blocker until hemodynamically stable. ICU admission mandatory.
📣 Sample Presentation
One-Liner
"Mrs. Patel is a 65-year-old with DM, HTN, and dyslipidemia presenting with exertional chest pressure × 3 days, now at rest. ECG shows ST depressions in V4-V6. Troponin trending 0.8→2.4→3.1. GRACE score 142 (high risk)."
Key Points to Cover on Rounds
Troponin peaked at 3.1, now downtrending. Started on heparin drip, ASA, ticagrelor load. Cardiology consulted -planned for cath tomorrow morning (early invasive strategy given high GRACE score). Atorvastatin 80 started. Metoprolol 12.5 BID. Pain controlled with nitroglycerin. No dynamic ECG changes overnight.
Monitoring Parameters -NSTEMI / Unstable Angina
Parameter
Frequency
Target / Action
Continuous telemetry
Duration of hospitalization (minimum 24-48h)
Monitor for VT/VF, new AF, bradycardia, ST changes. Ischemic ST changes on telemetry → repeat 12-lead ECG immediately.
Serial troponins
At presentation, 3h, 6h (until peak identified)
Rising pattern confirms NSTEMI. Plateau or decline = peak identified. Re-elevation after decline → reinfarction or stent thrombosis.
K⁺ > 4.0, Mg²⁺ > 2.0. Cr at 24 and 48h post-contrast. Cr rise > 0.5 = contrast nephropathy.
Hgb / Hct
Daily; more frequently if on anticoagulation or post-cath
Hgb drop > 2 without overt bleeding → access site bleed? retroperitoneal hemorrhage? GI bleed?
Red flags requiring immediate action: Recurrent chest pain with dynamic ECG changes, hemodynamic instability, new murmur (mechanical complication), unexplained Hgb drop (bleeding), acute HF symptoms.
🧪 Workup
Diagnostic Evaluation -NSTEMI / Unstable Angina
Serial troponins are essential. A rising pattern (delta) distinguishes acute MI from chronic troponin elevation. Use HEART score and TIMI risk score to guide disposition and invasive strategy timing.
Test
Rationale
Key Values
Serial troponins
Diagnose NSTEMI (rising/falling pattern). Draw at presentation, 3h, and 6h. Unstable angina = negative troponins with ischemic symptoms.
hs-cTnI or hs-cTnT: rising delta > 20% from baseline = acute injury. Peak troponin correlates with infarct size and prognosis.
12-lead ECG
ST depressions, T-wave inversions, or dynamic changes. Repeat with any symptom recurrence.
ST depression ≥ 0.5 mm in 2+ contiguous leads. New TWI ≥ 1 mm. Normal ECG does NOT exclude NSTEMI. Wellens' pattern (deep symmetric TWI in V2-V3) = critical LAD stenosis. LCx occlusion is often electrically silent -standard 12-lead has no posterior-facing leads, so isolated posterior/lateral wall ischemia may show only subtle ST depression in V1–V3 or no changes at all. If clinical suspicion is high despite a normal ECG, get posterior leads (V7–V9) and maintain a low threshold for serial ECGs and troponins.
HEART score
Risk stratification for chest pain. Guides disposition (discharge vs admit vs cath).
Baseline coags before anticoagulation. Lipid panel within 24h (LDL drops after 24-48h in acute MI).
Start high-intensity statin (atorvastatin 80 mg) regardless of LDL.
The "ECG-negative" NSTEMI -beware the LCx. The left circumflex artery supplies the posterior and lateral walls, which are poorly represented on a standard 12-lead ECG. An isolated LCx occlusion can present with ischemic symptoms, rising troponins, and a completely normal or near-normal ECG. This is one of the most commonly missed MIs. Always obtain posterior leads (V7–V9) when ACS is suspected and the standard ECG is unrevealing. Look for subtle reciprocal ST depression in V1–V3 (tall R waves, ST depression = posterior STEMI equivalent).
Type 2 MI (demand ischemia) -troponin elevation from supply-demand mismatch (sepsis, tachycardia, anemia, hypotension) rather than plaque rupture. Treat the underlying cause, not with cath. Distinguish from Type 1 (atherothrombotic) by clinical context.
💊 Medications
Key Medications -NSTEMI / Unstable Angina
Class
Drug / Dose
Key Pearls
Aspirin
ASA 325 mg loading (chew), then 81 mg daily indefinitely
Give immediately on presentation. Non-enteric coated for faster absorption. Continue lifelong.
Ticagrelor superior to clopidogrel PLATO, 2009. Prasugrel contraindicated if prior stroke/TIA, age ≥ 75, or weight < 60 kg. DAPT duration: minimum 12 months post-PCI.
Continue until cath or for duration of hospitalization if conservative strategy. Check aPTT q6h for UFH (goal 60-80s). Reduce enoxaparin to 1 mg/kg daily if CrCl < 30.
Beta-blocker
Metoprolol tartrate 12.5-25 mg PO q6-12h → titrate to HR 60-70
Start within 24h if no HF, cardiogenic shock, bradycardia, or heart block. Avoid IV beta-blocker acutely (increased cardiogenic shock risk). Convert to succinate for discharge.
Contraindicated if SBP < 90, RV infarct, PDE5 inhibitor within 24-48h. Provides symptom relief -does NOT reduce mortality.
Timing of invasive strategy: Immediate cath (< 2h) if refractory angina, hemodynamic instability, or VT/VF. Early invasive (within 24h) if GRACE > 140 or TIMI ≥ 3. Delayed invasive (25-72h) for lower-risk patients. Ischemia-guided (conservative) if low-risk and symptom-free.
⚡ Summary
Summary
NSTEMI or Unstable Angina
Both have ischemic symptoms without ST elevation; the troponin separates them.With high-sensitivity assays true unstable angina is increasingly rare, because almost every real ACS now shows a detectable troponin rise. Use serial troponins with a delta, since a single value neither confirms nor excludes.
GRACE Drives the Timing of Angiography
GRACE above 140 means early invasive within 24 h, which is the single most important cutoff on the page. Higher GRACE means more benefit from early angiography (TIMACS). Very high risk features, ongoing ischemia, hemodynamic or electrical instability, or mechanical complication, mean immediate angiography regardless of score.
Use the Right Score for the Right Decision
HEART is for emergency department disposition, who goes home and who is admitted.GRACE is the mortality predictor and drives invasive timing.TIMI is quick at the bedside but is the least discriminating.Applying a HEART cutoff to cath timing in an admitted NSTEMI is a category error: it was never validated for that decision.
Initial Therapy
Aspirin, anticoagulation (usually enoxaparin or unfractionated heparin), high-intensity statin, and a beta blocker within 24 h once stable.Nitrates and morphine for symptoms only, with the same caveats as in STEMI. Oxygen only if the saturation is below 90%.
Do Not Routinely Pre-Treat With a P2Y12 Inhibitor
ACCOAST showed prasugrel pre-treatment before angiography gave no ischemic benefit and increased bleeding.If an early invasive strategy is planned, wait until the coronary anatomy is known, so the agent can be chosen against the actual plan, including the possibility of urgent CABG.
Know the 2025 DAPT Change
Shorter dual antiplatelet therapy with a switch to ticagrelor monotherapy after 1 month, where the bleeding-reduction benefit is largest in NSTE-ACS. Short-course triple therapy for atrial fibrillation plus PCI, dropping aspirin early and continuing an oral anticoagulant with a P2Y12 inhibitor, since prolonged triple therapy bleeds far more than it prevents.
A Conservative Strategy Is Legitimate for Some
Low-risk patients, and those in whom revascularization would not be pursued because of frailty, severe comorbidity or patient preference, are managed medically with ischemia-guided testing. The choice should be explicit and documented, not the default that happens when nobody calls cardiology.
Watch for the Type 2 Trap and Killip Class
A troponin rise in sepsis, tachyarrhythmia, anemia or hypoxia is usually demand ischemia, not plaque rupture, and catheterizing those patients causes harm; treat the precipitant. Killip class at presentation carries strong prognostic weight (I no failure, II rales or S3, III pulmonary edema, IV cardiogenic shock) and feeds the GRACE score. Every discharge gets the full secondary-prevention package plus cardiac rehabilitation.
Comprehensive guide to cardiac arrhythmias -SVT, VT, long QT, Brugada, WPW, MAT, and more. Narrow vs wide, regular vs irregular -the approach is systematic. See also: Atrial Fibrillation & Heart Block & Bradyarrhythmias.
Jump to:SVTVT vs SVTFlutterSinus TachyMATJunctionalLong QTBrugadaWPWPACs/PVCsSick Sinus
Afib with WPW (DANGEROUS), polymorphic VT / Torsades, Afib with aberrancy
Afib + WPW → procainamide or cardiovert. NEVER adenosine/CCB/BB. Torsades → Mg 2g IV + defibrillate if pulseless.
Rule #1: Wide-complex tachycardia = VT until proven otherwise. Giving adenosine or CCBs to VT can cause hemodynamic collapse. When in doubt, treat as VT.
▶ AVNRT vs AVRT, How to Identify (tap to expand)
Both are types of PSVT* (paroxysmal supraventricular tachycardia): narrow-complex, regular tachycardias at 150–220 bpm with sudden onset and termination. Together they account for ~90% of PSVT. The distinction matters because a patient with an accessory pathway who later develops AFib can conduct at dangerous rates, management differs.
AVNRT* (AV Nodal Reentrant Tachycardia), ~60% of PSVT
Start with normal physiology. The AV node is the only electrical connection between atria and ventricles. Normally it acts as a single one-way funnel: one impulse at a time, with a built-in delay (~100 ms) that lets the atria finish contracting before the ventricles fire. In about 30% of adults there is a congenital variant in which the AV node contains two parallel functional pathways:
Slow pathway: slow conduction velocity, but SHORT refractory period (recovers quickly after firing).
Fast pathway: fast conduction velocity, but LONG refractory period (slow to recover).
In normal sinus rhythm the two pathways coexist silently. A sinus impulse travels down both at once, the fast path wins the race and activates the bundle of His, and the slow-path impulse arrives at tissue that is already depolarized and dies out. Baseline ECG is completely normal.
How the reentry loop starts (the premature beat trigger):
A premature atrial contraction (PAC) fires earlier than the next expected sinus beat.
The fast pathway is still in its long refractory period from the prior beat, so the PAC is blocked there.
The slow pathway has already recovered (short refractory period), so the PAC travels DOWN the slow pathway.
By the time the impulse reaches the distal AV node, the fast pathway has now recovered.
The impulse turns around and travels retrograde UP the fast pathway back to the top of the AV node.
At the top, the slow pathway has re-recovered, so the impulse descends it again.
Steps 3 through 6 repeat continuously. The loop lives entirely inside the AV node and spins at ~150–220 bpm.
Why the P wave hides in the QRS: each cycle discharges the ventricles (antegrade down the loop plus His-Purkinje) AND the atria (retrograde up the fast pathway) at almost the same moment. On the ECG, the retrograde P wave lands on top of the QRS and is invisible in ~60% of cases, or just peeks out at the end as a pseudo-R' in V1 or a pseudo-S in inferior leads. Short RP interval (< 70 ms) is the ECG signature (because the reentry loop is confined to the AV node, the atria and ventricles are depolarized at nearly the same instant, so the retrograde P wave has almost no time to separate from the QRS; contrast with AVRT, where the impulse must travel ventricle → accessory pathway → atrium, adding measurable delay and producing a longer RP).
Who: young to middle-aged adults, women > men, structurally normal hearts. Triggered by caffeine, alcohol, stress, stimulants.
ECG during SVT: narrow QRS, regular, rate 150–220.
P wave: buried in QRS or pseudo-R' in V1 (as described above).
RP interval: very short (< 70 ms), classic "short RP" tachycardia.
Baseline ECG (sinus rhythm): usually normal. No delta wave.
AVRT* (AV Reciprocating Tachycardia), ~30% of PSVT
Start with normal anatomy. Atria and ventricles are electrically insulated from each other by the fibrous skeleton of the heart. The AV node is the ONLY legitimate electrical connection between them, and its conduction delay is what staggers atrial and ventricular contraction.
The accessory pathway (AP). In AVRT, there is a congenital strand of muscle that pierces the fibrous skeleton and directly connects an atrium to a ventricle, bypassing the AV node entirely. The classic example is the bundle of Kent in WPW* (Wolff-Parkinson-White) syndrome. Because the accessory pathway is ordinary myocardium, it has key properties that differ from the AV node:
No physiologic AV delay. It conducts as fast as ordinary atrial or ventricular muscle, so impulses cross it nearly instantly.
Longer refractory period than the AV node (in most cases).
May conduct in both directions, or only retrograde (ventricle to atrium), which is called a "concealed" pathway because the baseline ECG looks totally normal.
Why manifest WPW produces a delta wave at baseline: in sinus rhythm the impulse travels down BOTH routes simultaneously. The accessory pathway has no AV delay, so it reaches the ventricle FIRST and begins depolarizing a small patch of ventricular myocardium before the AV node gets there. That early, muscle-to-muscle spread creates:
Short PR interval (< 120 ms): the AV node delay is partially bypassed.
Delta wave: a slurred, slow upstroke at the start of the QRS, caused by that early pre-excited myocardium depolarizing slowly from cell to cell before the His-Purkinje system catches up.
Slightly widened QRS: a fusion beat of accessory-pathway conduction + normal node conduction.
How the reentry loop starts (orthodromic AVRT, ~95% of AVRT episodes):
A PAC fires earlier than the next sinus beat.
The accessory pathway is still refractory (longer refractory period than the AV node), so the PAC cannot cross it.
The PAC travels down the AV node only. Ventricle depolarizes normally through His-Purkinje, producing a narrow QRS.
By the time the ventricle is fully depolarized, the accessory pathway has now recovered.
The impulse crosses retrograde UP the accessory pathway from ventricle back to atrium.
The atrium is re-activated, and the impulse descends the AV node again.
Steps 3 through 6 repeat at ~150–220 bpm. The circuit uses the WHOLE heart as its substrate: atrium, AV node, ventricle, accessory pathway, back to atrium.
Antidromic AVRT (~5%): same loop running in reverse. The PAC catches the AV node refractory, the impulse descends the ACCESSORY pathway, the ventricle is activated entirely from the pathway insertion point (producing a wide, bizarre QRS that is indistinguishable from VT on morphology), then travels retrograde up the AV node.
Why the P wave shows up AFTER the QRS in orthodromic AVRT: the atrium is activated by retrograde conduction through the accessory pathway ONLY AFTER the ventricle has fully depolarized. That sequence (ventricle, then pathway, then atrium) takes measurable time, so the retrograde P wave appears clearly on the ST segment or early T wave, inverted in II/III/aVF. Long RP interval (> 70 ms). Contrast this with AVNRT, where atria and ventricles fire almost simultaneously and the P is hidden.
Who: often younger patients. Some have a known pre-excitation pattern (delta wave + short PR) on baseline ECG; others first present with SVT and have a concealed pathway.
ECG during SVT: narrow QRS in orthodromic (~95%), wide QRS in antidromic (~5%).
P wave: visible after the QRS, inverted in II/III/aVF (as described above).
RP interval: long (> 70 ms).
Baseline ECG (sinus rhythm): delta wave + short PR + slightly widened QRS if manifest WPW; completely normal if the pathway is concealed (retrograde-only).
Side-by-Side Differentiation
Feature
AVNRT
AVRT (Orthodromic)
Frequency
~60% of PSVT
~30% of PSVT
Circuit
Entirely within the AV node (dual pathways)
Uses an accessory pathway outside the AV node
P wave location
Buried in the QRS, OR pseudo-R' in V1 immediately after QRS
Visible after the QRS, on the ST segment or T wave (retrograde)
RP interval
Short (< 70 ms),"short RP" tachycardia
Long (> 70 ms), longer RP
Baseline ECG (sinus)
Normal
May show delta wave + short PR (manifest WPW); normal if pathway is concealed
QRS width during SVT
Narrow (unless pre-existing BBB)
Narrow in orthodromic (~95%); wide in antidromic (~5%)
Risk profile
Benign; recurrent episodes, not life-threatening
Accessory pathway + AFib → can conduct at 300+ bpm to ventricles → VF and sudden death
First-line acute treatment
Vagal maneuvers → adenosine 6 mg → 12 mg (third 12 mg dose no longer in the AHA algorithm)
Same for narrow/regular presentation. If AFib with pre-excitation: procainamide or cardioversion. NEVER adenosine / CCB / BB / digoxin.
Definitive therapy
Slow-pathway ablation (> 95% cure)
Accessory-pathway ablation (> 95% cure)
Bedside identification workflow:
Narrow QRS, regular, rate 150–220? → PSVT (AVNRT or AVRT most likely).
Look for the P wave:
Buried in QRS or pseudo-R' in V1 → AVNRT.
Visible after QRS, inverted in II/III/aVF → AVRT (orthodromic).
Check a prior baseline ECG. Delta wave + short PR at rest → accessory pathway → AVRT.
Adenosine response. Both terminate with adenosine (the AV node is part of both circuits), so response does NOT differentiate them during SVT. Adenosine is useful as a diagnostic tool when it transiently unmasks underlying atrial flutter or tachycardia.
⚠️ The life-threatening scenario: pre-excited AFib. A patient with an accessory pathway who develops atrial fibrillation can conduct AFib impulses at 250–300+ bpm directly to the ventricles via the bypass tract, since the AV node's rate-limiting protection is skipped. The ECG shows wide, irregular, very fast QRS complexes, pre-excited AFib, which can degenerate into VF. NEVER give AV-nodal blockers (adenosine, verapamil, diltiazem, beta-blockers, digoxin): blocking the AV node forces all conduction through the accessory pathway and accelerates the ventricular rate. Treat with IV procainamide (slows accessory pathway conduction) or synchronized cardioversion if unstable.
VT vs SVT with Aberrancy -How to Tell Them Apart
Both present as wide-complex tachycardia. Getting this wrong can be fatal -treating VT with a calcium channel blocker causes hemodynamic collapse. When in doubt, always treat as VT.
Feature
Favors VT
Favors SVT with Aberrancy
AV dissociation
✅ Most specific for VT. P waves march independently at a different rate from QRS.
❌ Absent -P waves are associated with each QRS (1:1 relationship).
Fusion & capture beats
✅ Pathognomonic for VT. Fusion = P wave partially captures ventricle mid-VT. Capture = sinus beat "captures" ventricle (narrow QRS in midst of wide complexes).
❌ Not seen.
QRS width
✅ > 160 ms strongly favors VT. Extremely wide (> 200 ms) = almost certainly VT.
Typically 120–140 ms (bundle branch block pattern).
QRS morphology
✅ Bizarre, atypical -doesn't look like a classic RBBB or LBBB pattern.
Looks like a typical RBBB or LBBB (rsR' in V1, or rS in V1 with broad R in V6).
Concordance
✅ All precordial leads (V1–V6) deflect in the same direction (all positive or all negative) = VT.
✅ Extreme axis deviation (negative in I and aVF) = almost always VT.
Axis is within normal or expected BBB range.
RS interval in precordial leads
✅ RS interval > 100 ms in any precordial lead (Brugada criterion) favors VT.
RS interval < 100 ms.
Absence of RS complex
✅ No RS complex in any V1–V6 lead (all QS or monophasic R) = VT.
RS complexes present in at least one precordial lead.
History
✅ Prior MI, known cardiomyopathy, HF, structural heart disease -VT is overwhelmingly more likely.
Young, no structural heart disease, known SVT/BBB on prior ECG.
Hemodynamic stability
⚠️ Does NOT help differentiate. VT can be hemodynamically stable. Do not assume stable = SVT.
⚠️ Same -SVT with aberrancy can also be unstable.
Response to adenosine
❌ No effect (VT does not involve AV node). ⚠️ Adenosine is generally safe but NOT diagnostic -VT that doesn't terminate ≠ SVT.
✅ Terminates or slows (involves AV node reentry). But only give if you're reasonably confident it's SVT.
⚠️ The Brugada Algorithm for Wide-Complex Tachycardia: Step 1: Absence of RS complex in ALL precordial leads? → VT Step 2: RS interval > 100 ms in any precordial lead? → VT Step 3: AV dissociation present? → VT Step 4: Morphology criteria for VT in V1 and V6? → VT
If none of the above → SVT with aberrancy. Sensitivity > 98% for VT.
Clinical Pearl: In patients > 50 years old with structural heart disease presenting with wide-complex tachycardia, the diagnosis is VT in ~80% of cases. Age + prior MI = treat as VT until proven otherwise. It is always safer to treat SVT as VT (cardioversion works for both) than to treat VT as SVT (CCBs/adenosine in VT → cardiac arrest).
Atrial Flutter
Sawtooth pattern in II, III, aVF (best seen in II). Rate typically ~300 bpm with 2:1 block → ventricular rate ~150 bpm.
If the ventricular rate is exactly ~150 bpm → think flutter until proven otherwise.
Management: same as Afib (rate control, anticoagulation by CHA₂DS₂-VASc). Often responds better to cardioversion and ablation than to drugs.
Ablation cure rate for typical (CTI-dependent) flutter is > 95% -refer early.
Sinus Tachycardia
Sinus tachycardia is NOT a primary arrhythmia -it is a physiologic response. Do NOT treat sinus tachycardia with antiarrhythmics. Find and treat the underlying cause.
≥ 3 distinct P-wave morphologies with varying P-P, PR, and R-R intervals. Irregular rhythm.
NOT Afib -MAT has discrete P waves before each QRS (Afib has no organized P waves).
Almost always associated with severe underlying illness: COPD exacerbation, hypoxia, hypercapnia, hypomagnesemia, heart failure, theophylline use.
Treatment = treat the underlying cause. Correct Mg²⁺ and K⁺. Improve oxygenation. Treat COPD.
⚠️ Do NOT cardiovert MAT -it will not work (multiple foci, not a single reentrant circuit).
If rate control needed: IV magnesium 2g first. Then non-dihydropyridine CCB (verapamil/diltiazem) if no HF. Avoid beta-blockers in COPD-driven MAT.
Junctional Rhythms
Junctional escape rhythm (40–60 bpm): narrow QRS, absent/retrograde P waves. Occurs when SA node fails or slows (sinus bradycardia, sick sinus, high vagal tone).
Accelerated junctional rhythm (60–100 bpm): enhanced automaticity of AV junction. Causes: digoxin toxicity (#1), inferior MI, post-cardiac surgery, myocarditis.
Junctional tachycardia (> 100 bpm): rare in adults. Think dig toxicity or post-surgical.
Treatment: identify and treat the cause. If dig toxicity → hold digoxin, check level, give Digibind if hemodynamically unstable.
⚠️ Accelerated junctional rhythm + regularization of previously irregular rhythm = think digoxin toxicity until proven otherwise.
Long QT Syndrome
Prolonged QTc (> 500 ms) = high risk for Torsades de Pointes (TdP) -a polymorphic VT that can degenerate into VF and sudden death.
⚠️ QTc > 500 ms = STOP all QT-prolonging agents immediately. Correct K⁺ to > 4.0 and Mg²⁺ to > 2.0. If Torsades develops: Mg 2g IV push → overdrive pacing or isoproterenol to increase HR (shortens QT). Defibrillate if pulseless.
Brugada Syndrome
ECG pattern: Coved ST elevation (> 2 mm) with T-wave inversion in V1–V3 (Type 1 = diagnostic). Type 2 (saddleback) is suggestive but not diagnostic. Consider high V1–V2 leads (2nd/3rd intercostal space) to unmask.
Risk: Sudden cardiac death from VF, often during rest or sleep. Young males (20–40), Southeast Asian descent.
Genetics: SCN5A mutation (Na⁺ channel loss-of-function) in ~20–30% of cases. Autosomal dominant.
Triggers (avoid): Fever (#1, aggressive antipyretics for any febrile illness), sodium channel blockers (Class I antiarrhythmics, TCAs, cocaine, propofol in high doses), electrolyte disturbances, alcohol, large meals at night.
Provocation test: IV procainamide, ajmaline, or flecainide, unmasks Type 1 pattern in ambiguous cases. Do only in controlled EP lab setting.
Management:ICD if prior cardiac arrest, spontaneous Type 1 pattern with syncope, or sustained VT. Quinidine (unique sodium-channel blocker that paradoxically helps in Brugada, blocks Ito current). Isoproterenol drip for electrical storm. Family screening with ECG.
Do NOT give Class I antiarrhythmics (flecainide, procainamide, lidocaine, except for provocation testing), they worsen the ECG and increase VF risk.
Wolff-Parkinson-White (WPW) -Expanded
ECG triad: Short PR (< 120 ms) + delta wave (slurred QRS upstroke) + wide QRS (> 120 ms). Caused by an accessory pathway (Bundle of Kent) bypassing the AV node.
Orthodromic AVRT (~95%): Impulse goes DOWN the AV node, UP the accessory pathway. Narrow QRS. Treat like SVT (adenosine safe).
Antidromic AVRT (~5%): Impulse goes DOWN the accessory pathway, UP the AV node. Wide QRS -looks like VT. Procainamide or cardiovert.
⚠️ Afib + WPW = LETHAL COMBINATION. Rapid conduction down the accessory pathway → extremely fast ventricular rates → VF → cardiac arrest.
NEVER give AV nodal blockers: adenosine, beta-blockers, calcium channel blockers, digoxin. These block the AV node and force ALL conduction down the accessory pathway.
Treatment: Procainamide IV (slows accessory pathway) or synchronized cardioversion. If unstable → immediate cardioversion.
Premature Beats (PACs & PVCs)
Feature
PAC (Premature Atrial Contraction)
PVC (Premature Ventricular Contraction)
Origin
Ectopic atrial focus (above AV node)
Ventricular myocardium (below AV node)
P Wave
Present -early, abnormal morphology (differs from sinus P)
Absent -no preceding P wave
QRS
Narrow (< 120 ms) -conducts normally through His-Purkinje
Wide & bizarre (> 120 ms) -cell-to-cell spread, NOT His-Purkinje
QRS Axis
Same as baseline -normal conduction pathway preserved
Different from baseline -axis points away from PVC origin. RVOT PVCs → LBBB + inferior axis. LV PVCs → RBBB morphology.
Compensatory Pause
Usually non-compensatory (incomplete) -SA node resets
Usually full compensatory pause -SA node not reset
Pulse on Exam
Normal pulse -patient may feel a brief "skip"
Weaker pulse (↓ filling time → ↓ stroke volume). May drop the beat entirely on radial pulse. Followed by a stronger "thud" beat after the pause.
Clinical Significance
Almost always benign. Common with caffeine, stress, alcohol. Frequent PACs may predict future Afib.
Very early PACs may conduct aberrantly (usually RBBB pattern -right bundle has longer refractory period) → wide QRS but axis still normal
Always wide QRS with abnormal axis. If wide-complex beat has same axis as baseline → think aberrant PAC, not PVC.
Management
Reassurance. Reduce caffeine/alcohol if symptomatic. Rarely need treatment.
< 10% burden + normal echo: reassure, BB if symptomatic. > 10–15% burden: echo to check EF, consider ablation. CAST, 1991 -⚠️ do NOT suppress PVCs with Class Ic agents post-MI.
Presentation: Syncope, presyncope, fatigue, exercise intolerance. Often elderly with fibrosis of the SA node.
Diagnostic clue: Bradycardia that doesn't respond to atropine + intermittent tachyarrhythmias.
Treatment:Permanent pacemaker (allows safe use of rate-control drugs for the tachycardia component). Without a pacer, rate-controlling drugs worsen the bradycardia.
Key point: You can't treat the tachy without a pacer to protect against the brady.
Related topics: For detailed Afib management (rate/rhythm control, CHA₂DS₂-VASc, anticoagulation), see Atrial Fibrillation. For AV block classification and pacing indications, see Heart Block & Bradyarrhythmias.
Monitoring -Arrhythmias
Parameter
Frequency
Target
Continuous telemetry
Until rhythm stable ×24h
Identify recurrence, assess rate control
12-lead ECG
After conversion + daily
Confirm sinus rhythm, rule out pre-excitation (delta wave → WPW)
Vitals
q4h
HR, BP -especially after starting rate/rhythm control agents
Vagal maneuvers first. Modified Valsalva (blow into syringe for 15 sec, then lie flat with legs elevated -conversion rate ~43% vs 17% for standard Valsalva REVERT, 2015). Carotid sinus massage (avoid if carotid bruit).
Step 2 -Adenosine
Adenosine 6 mg rapid IV push (antecubital, followed by 20 mL NS flush and arm elevation). If no effect in 1–2 min → 12 mg → 12 mg.Half-life = 6 seconds. Warn patient: transient chest tightness, flushing, sense of doom.
Step 3 -If refractory
Diltiazem 0.25 mg/kg IV (repeat 0.35 mg/kg in 15 min if needed) or verapamil 5 mg IVACC/AHA/HRS SVT Guidelines, 2015. Or synchronized cardioversion (50–100J biphasic) if unstable or refractory to all drugs.
Synchronized cardioversion 100–200J. Sedate first if time permits.
Stable monomorphic VT
Amiodarone 150 mg IV over 10 min → 1 mg/min × 6h → 0.5 mg/min × 18h. Alternative: procainamide 20–50 mg/min until rhythm converts (monitor QRS width and BP). Lidocaine 1–1.5 mg/kg as third option.
Polymorphic VT / Torsades
Magnesium 2g IV push. If pulseless → defibrillate (unsynchronized). Stop QT-prolonging drugs. Overdrive pacing or isoproterenol to increase HR (shortens QT). IV potassium to K⁺ > 4.5.
Long QT / Torsades -Acute Management
1
STOP all QT-prolonging agents immediately -review med list (antiarrhythmics, antibiotics, antipsychotics, antiemetics).
2
Magnesium 2g IV over 2–5 min -first-line even if Mg level is normal. Stabilizes cardiac membrane.
3
Correct electrolytes: K⁺ to > 4.0 mEq/L, Mg²⁺ to > 2.0 mg/dL, Ca²⁺ normal.
4
If Torsades persists → overdrive pacing (temporary transvenous pacer at rate 90–110 bpm) or isoproterenol drip to increase HR (shortens QT interval). Target HR > 90.
5
If pulseless → defibrillate (unsynchronized) 120–200J biphasic. Do NOT use synchronized cardioversion for polymorphic VT.
⚠️ Do NOT give amiodarone for Torsades -amiodarone itself prolongs QT and will worsen the arrhythmia.
MAT -Management
Step 1: Treat the underlying cause -optimize COPD, correct hypoxia, treat HF/sepsis.
Step 2:IV magnesium 2g -often converts or slows MAT.
Step 3: If rate control needed → non-dihydropyridine CCB (verapamil/diltiazem). Avoid beta-blockers if COPD is the driver.
⚠️ Cardioversion does NOT work for MAT -multiple automatic foci, not a reentrant circuit.
⚠️ Antiarrhythmics are not effective -focus on the underlying disease.
Electrical Cardioversion -Quick Reference
Rhythm
Synchronized?
Energy (Biphasic)
Notes
SVT
✅ Synchronized
50–100J
Sedate first (propofol, midazolam, or etomidate)
Atrial Flutter
✅ Synchronized
50–100J
Often converts at low energy
Atrial Fibrillation
✅ Synchronized
120–200J
Higher energy needed. Anticoagulate ≥ 3 weeks pre or TEE to rule out LAA thrombus.
Monomorphic VT (stable)
✅ Synchronized
100J → 200J → 300J → 360J
Escalate if first shock fails
Polymorphic VT / Torsades
❌ Unsynchronized (DEFIB)
120–200J
Can't sync to irregular rhythm -treat as VF
VF / Pulseless VT
❌ Unsynchronized (DEFIB)
120–200J
ACLS protocol. CPR between shocks.
Synchronized = shock on R wave (avoids vulnerable T-wave period which could cause VF). Unsynchronized = shock immediately (for VF/pulseless VT/polymorphic VT where there's no reliable R wave to sync to).
📋 On Rounds
Pimp Questions
How do you differentiate SVT with aberrancy from VT?
Several ECG criteria favor VT: (1) AV dissociation (P waves marching through at different rate -most specific), (2) fusion and capture beats, (3) very wide QRS > 160 ms, (4) concordance (all precordial leads same direction), (5) Brugada criteria (absence of RS complex in all precordial leads, RS interval > 100 ms). In practice: if in doubt, treat as VT -it's safer to cardiovert SVT than to give a calcium channel blocker to VT.
What did the REVERT trial show about Valsalva technique?
REVERT, 2015: the modified Valsalva (strain for 15 seconds in semi-recumbent position, then immediately lie flat with legs passively raised to 45° for 15 seconds) converted SVT in 43% of patients vs 17% with standard Valsalva. The leg raise augments venous return → increases vagal tone. Simple, free, and should be tried before adenosine.
What is the modified Valsalva technique and why is it more effective?
The REVERT trial (2015) showed the modified Valsalva converts SVT at 43% vs 17% for standard Valsalva. Technique: patient blows into a 10 mL syringe (generating ~40 mmHg intrathoracic pressure) for 15 seconds while sitting at 45° → immediately lay them flat and passively raise both legs to 45° for 15 seconds. The leg raise augments venous return → stretches the right atrium → enhances vagal tone. This should be attempted before adenosine.
A patient has SVT and you notice a delta wave on the baseline ECG. What do you NOT give?
Do NOT give adenosine, beta-blockers, calcium channel blockers, or digoxin -any AV nodal blocker is dangerous in WPW (Wolff-Parkinson-White). These drugs slow conduction through the AV node but don't affect the accessory pathway. If the patient develops Afib (which is common in WPW), the accessory pathway conducts at high rates without AV nodal braking → ventricular fibrillation and death.
Brugada syndrome is a channelopathy (SCN5A Na⁺ channel mutation in ~25%) causing coved ST elevation in V1–V3 with risk of sudden cardiac death from VF, typically at rest or during sleep. The biggest trigger is fever -it unmasks or worsens the Brugada pattern and can precipitate VF. Treat fever aggressively with acetaminophen and admit for monitoring. Other triggers: Na⁺ channel blockers (flecainide, TCAs), cocaine, alcohol, vagal stimulation.
How do you differentiate MAT from Afib on ECG?
Both are irregular, but: MAT has discrete P waves before each QRS -at least 3 different P-wave morphologies with varying P-P, PR, and R-R intervals. Afib has NO organized P waves -just a fibrillating baseline with irregularly irregular ventricular response. MAT is almost always seen in severe COPD or critical illness. Key management difference: MAT cannot be cardioverted (multiple automatic foci, not reentrant).
When do PVCs need further workup?
PVCs need workup when: (1) PVC burden > 10–15% on Holter monitor (risk of PVC-induced cardiomyopathy), (2) symptomatic (palpitations, presyncope, exercise intolerance), (3) structural heart disease present or suspected, (4) new-onset PVCs post-MI, (5) multifocal PVCs or R-on-T phenomenon. Workup: echo (assess EF), Holter (quantify burden), consider cardiac MRI if cardiomyopathy suspected. CAST trial
What is the CAST trial and why is it one of the most important arrhythmia trials?
CAST, 1991: The Cardiac Arrhythmia Suppression Trial tested whether suppressing PVCs with Class Ic antiarrhythmics (flecainide, encainide) after MI would reduce sudden cardiac death. The trial was stopped early because patients on flecainide/encainide had 3.6× higher mortality than placebo. This was a paradigm shift: just because you can suppress an arrhythmia on the monitor doesn't mean you improve outcomes.
Case 1: Young Woman with Palpitations
Presentation: 28-year-old woman presents to the ED with sudden-onset palpitations lasting 45 minutes. She reports "fluttering" in her chest and mild lightheadedness. No syncope, chest pain, or dyspnea. No prior cardiac history. Two cups of coffee this morning.
Vitals: HR 182 (regular), BP 108/72, RR 18, SpO₂ 99% on RA.
ECG: Narrow-complex regular tachycardia at 180 bpm. No discernible P waves. No delta wave on prior baseline ECG.
Question: What is the most likely rhythm and your first intervention?
Management: Most likely AVNRT (most common SVT in young women). Start with modified Valsalva per REVERT, 2015 (blow into syringe 15s → lie flat with legs raised 15s). If unsuccessful, Adenosine (Adenocard) 6 mg rapid IV push → 12 mg if no response. Post-conversion ECG confirms sinus rhythm with no pre-excitation. Discharge with cardiology referral for EP study and catheter ablation (cure rate >95%).
Case 2: Elderly Patient on Digoxin with Atrial Tachycardia
Presentation: 79-year-old man with HFrEF (EF 30%) and chronic Afib on Digoxin (Lanoxin) 0.125 mg daily presents with nausea, blurred vision, and new palpitations. He reports seeing "yellow halos" around lights.
Vitals: HR 146 (irregularly irregular with pauses), BP 98/64, RR 20, SpO₂ 94% on 2L NC.
ECG: Atrial tachycardia with variable block. Multiple P-wave morphologies with grouped beating pattern. Baseline ST scooping ("digitalis effect").
Question: Is this MAT or digitalis toxicity? What is your next step?
Management: Classic digitalis toxicity, atrial tachycardia with block + GI symptoms + visual changes. Hold digoxin immediately. Check digoxin level (therapeutic 0.5–2.0 ng/mL), K⁺ (hypokalemia worsens toxicity), Mg²⁺, and Cr. Distinguish from MAT (≥3 P-wave morphologies, seen in severe COPD). If hemodynamically unstable or level markedly elevated, give Digoxin Immune Fab (Digibind). Replete K⁺ >4.0 and Mg²⁺ >2.0. Avoid cardioversion (risk of refractory VF in dig toxicity).
Case 3: WPW with Antidromic Tachycardia
Presentation: 34-year-old man brought in by EMS after collapsing at the gym. He is diaphoretic and pale with a weak pulse. Prior ECG on file shows a short PR interval and delta wave (known WPW). No prior ablation.
Vitals: HR 224 (irregular), BP 82/50, RR 24, SpO₂ 92% on RA.
ECG: Wide-complex irregular tachycardia. Varying QRS morphology. Rates 180–260 bpm. Consistent with pre-excited atrial fibrillation (Afib conducting over the accessory pathway).
Question: What drugs must you avoid and why?
Management:Avoid ALL AV nodal blockers, Adenosine (Adenocard), Diltiazem (Cardizem), Metoprolol (Lopressor), and Digoxin (Lanoxin) are contraindicated. These slow AV node conduction but leave the accessory pathway uninhibited → unopposed rapid conduction → ventricular fibrillation. Given hemodynamic instability, proceed to synchronized cardioversion (120–200J biphasic). If stable, use Procainamide (Pronestyl) 15–17 mg/kg IV to slow accessory pathway conduction. Urgent cardiology consult for catheter ablation.
📣 Sample Presentation
One-Liner
"Ms. Rivera is a 32-year-old healthy woman presenting with sudden palpitations and HR 186, narrow-complex regular tachycardia on ECG consistent with SVT. Hemodynamically stable. Broke with adenosine 12 mg after failing 6 mg."
Key Points to Cover on Rounds
Converted to sinus rhythm after second adenosine bolus. Post-conversion ECG: normal sinus, no delta wave (WPW ruled out), no short PR. K⁺ 3.8, Mg 2.1 -within normal. TSH normal. No structural heart disease on prior records. First episode, no recurrence. Plan: discharge with cardiology follow-up, consider EP referral if recurrent.
Monitoring
Parameter
Frequency
Target / Action
CRP
Weekly until normal
Guides duration of therapy. Do NOT taper NSAIDs until CRP normalizes. Premature taper = recurrence.
ECG
At diagnosis, then at follow-up
Monitor ST/PR normalization through 4 stages. Persistent changes may suggest constrictive physiology.
TTE (Echo)
Repeat in 1-2 weeks
Confirm effusion resolution. Repeat sooner if hemodynamic compromise or clinical worsening.
12-lead ECG during tachycardia is the most important diagnostic step. Capture it BEFORE giving adenosine -it is both diagnostic AND therapeutic, and you lose the diagnostic ECG once the rhythm converts.
12-lead ECG during tachycardia -narrow complex (< 120 ms)? Regular or irregular? P waves visible? Relationship of P to QRS? Short RP vs long RP? These features differentiate AVNRT, AVRT, and atrial tachycardia.
Adenosine (6 mg → 12 mg rapid IV push) -diagnostic AND therapeutic. Terminates re-entrant SVTs involving the AV node (AVNRT, AVRT). If it doesn't terminate but reveals underlying atrial activity (flutter waves, atrial tachycardia) → the diagnosis is NOT AVNRT/AVRT.
BMP -K⁺ (hypokalemia triggers arrhythmias), Mg²⁺ (low Mg → refractory hypoK and arrhythmias), Ca²⁺ (hypercalcemia can shorten QT)
TSH -hyperthyroidism is a common reversible cause of SVT and atrial fibrillation. Check in all new-onset SVT.
Troponin -if prolonged SVT (sustained rapid rates can cause demand ischemia, especially in CAD patients) or if chest pain is present
Echocardiogram -if recurrent SVT, to assess for structural heart disease (WPW with accessory pathway, hypertrophic cardiomyopathy, valvular disease). Not urgent for first isolated episode with normal ECG.
Key ECG features: Narrow complex + regular + no visible P waves = likely AVNRT (most common SVT). Narrow + regular + retrograde P waves in ST segment = AVRT. Narrow + regular + different P wave morphology = atrial tachycardia. Narrow + irregularly irregular = atrial fibrillation (not SVT). Look for delta waves on baseline ECG → WPW (avoid AV nodal blockers).
💊 Medications
Vaughan-Williams Antiarrhythmic Classification
The classic framework for understanding antiarrhythmic drugs. Each class targets a different ion channel. Know the class, MOA, and dangerous side effects.
First-line for stable narrow-complex SVT (AVNRT/AVRT). Diagnostic (unmasks underlying rhythm). 6 mg → 12 mg rapid IV push (two doses; the third 12 mg was dropped from the AHA algorithm).
⚠️ Transient: chest tightness, flushing, dyspnea, sense of doom (warn patient!) ⚠️ Contraindicated in WPW + Afib, severe asthma, 2nd/3rd degree heart block ⚠️ Theophylline/caffeine antagonize. Dipyridamole/carbamazepine potentiate → reduce dose.
Digoxin (Lanoxin)
Inhibits Na⁺/K⁺-ATPase → increases vagal tone (slows AV conduction). Also increases intracellular Ca²⁺ → positive inotropy.
Rate control in Afib (especially with HF -provides inotropy + rate control). Third-line in most settings.
⚠️ Narrow therapeutic window (0.5–2.0 ng/mL). Toxicity: N/V, visual changes (yellow halos), arrhythmias (accelerated junctional, bidirectional VT, PAT with block) ⚠️ Hypokalemia and hypomagnesemia worsen toxicity ⚠️ Toxicity antidote: Digibind (digoxin-specific Fab antibodies)
Magnesium
Stabilizes cardiac cell membranes. Suppresses early afterdepolarizations. Essential cofactor for Na⁺/K⁺-ATPase.
First-line for Torsades de Pointes. Adjunct in MAT. Electrolyte repletion in any arrhythmia.
⚠️ Flushing, hypotension (if given too fast), loss of deep tendon reflexes (toxicity), respiratory depression (severe toxicity)
Atropine
Muscarinic (M₂) receptor antagonist → blocks vagal input to SA/AV node → increases HR and conduction.
First-line for symptomatic bradycardia. 0.5 mg IV q3–5min (max 3 mg). Bridge to transcutaneous/transvenous pacing.
⚠️ Tachycardia, urinary retention, dry mouth, mydriasis, delirium (especially elderly) ⚠️ Ineffective in infranodal block (Mobitz II, 3rd degree with wide escape) -go straight to pacing
Drug interactions & renal dosing: Always check Drug Interactions and CrCl Calculator before prescribing antiarrhythmics. Many require renal dose adjustment (dofetilide, sotalol, digoxin, procainamide).
⚡ Summary
Summary
Rule Number One
A wide-complex tachycardia is ventricular tachycardia until proven otherwise.Giving adenosine or a calcium channel blocker to VT can cause hemodynamic collapse.When in doubt, treat as VT: the cost of treating SVT as VT is small, the cost of the reverse is an arrest. A history of structural heart disease or prior MI makes VT far more likely.
Unstable Means Electricity, Whatever the Rhythm
Hypotension, altered mental status, ischemic chest pain, acute heart failure or shock → synchronized cardioversion now.Do not spend time on drugs in an unstable patient, and sedate if there is time. Pulseless VT and VF are defibrillated, not cardioverted.
Identify Narrow-Complex SVT at the Bedside
Narrow QRS, regular, rate 150 to 220 suggests AVNRT or AVRT.Find the P wave: buried in the QRS or a pseudo-R prime in V1 points to AVNRT; visible after the QRS and inverted inferiorly points to AVRT. Irregularly irregular means atrial fibrillation; a sawtooth baseline at about 300 with 2:1 conduction means flutter at 150.
Vagal Then Adenosine for Stable SVT
Try the modified Valsalva first, which converts substantially more patients than the standard version (REVERT). Then adenosine 6 mg rapid IV push with an immediate flush, then 12 mg.Warn the patient it feels awful and is brief.Run a continuous rhythm strip through the push: even when it does not convert, the transient AV block unmasks the underlying atrial rhythm and makes the diagnosis.
Know When Adenosine Is the Wrong Drug
Avoid in pre-excited atrial fibrillation (WPW with an irregular wide-complex tachycardia), where blocking the AV node pushes conduction down the accessory pathway and can precipitate ventricular fibrillation. The same applies to verapamil, diltiazem, beta blockers and digoxin in that rhythm.Use procainamide or cardioversion instead. Adenosine is also less effective in patients on theophylline and exaggerated in those on dipyridamole or with a transplanted heart.
Torsades Is Treated Differently From Other VT
Magnesium sulfate 2 g IV, even when the magnesium level is normal.Stop every QT-prolonging drug and correct potassium and magnesium.Overdrive pacing or isoproterenol for pause-dependent torsades, since increasing the rate shortens the QT. Amiodarone is contraindicated: it prolongs the QT further.
Stable Monomorphic VT
Amiodarone, procainamide or lidocaine, with procainamide the most effective for conversion (PROCAMIO) though it needs blood pressure monitoring. Correct the reversible drivers: potassium, magnesium, ischemia and drug toxicity. Have the defibrillator at the bedside, because stable VT becomes unstable without warning.
Multifocal Atrial Tachycardia Is a Lung Diagnosis
Three or more distinct P wave morphologies with an irregular rhythm, classically in COPD exacerbation.Treat the lung disease and correct hypoxia, hypokalemia and hypomagnesemia; the rhythm follows.Cardioversion does not work and beta blockers are usually contraindicated; verapamil is the drug if rate control is genuinely needed. Also plan the definitive therapy: recurrent AVNRT and AVRT are cured by ablation, with high success and low complication rates.
RoundsRx Infographic Series · #18 · Cardiovascular · PDF 148 KB
Text version
Cardiology · One Pager
SVT
Narrow, regular, fast. Modified Valsalva first, then adenosine. Check for WPW before AV nodal blockers. Unstable → cardiovert.
💊 Key Drugs
Adenosine6 mg → 12 mg rapid push
Diltiazem20 mg IV over 2 min
Metoprolol5 mg IV q5min × 3
Procainamide15-17 mg/kg IV (WPW)
⚠️ Pitfalls
AV nodal blockers in WPW → VF
Not trying modified Valsalva first
Missing atrial flutter (2:1 looks like SVT at 150)
Adenosine in wide-complex tachycardia
UrgentCardiology
Pericarditis & Pericardial Disease
Inflammation of the pericardium. Usually viral and self-limited. The danger: missing tamponade and confusing it with STEMI. Colchicine reduces recurrence by 50%.
🔍 Overview
Diagnosis (≥ 2 of 4 criteria)
Pleuritic chest pain -sharp, worse with inspiration and supine, improved leaning forward
Tamponade is a clinical diagnosis, not an echocardiographic one. A large effusion can be well-tolerated (chronic); a small rapidly accumulating effusion can cause tamponade.
Beck's triad: hypotension, JVD, muffled heart sounds (only ~30% have all three)
Pulsus paradoxus > 10 mmHg (SBP drop > 10 with inspiration) -most sensitive clinical sign
Echo: RA collapse in systole (earliest), RV diastolic collapse, IVC plethora (no collapse with inspiration)
Electrical alternans on ECG (swinging heart) -classic but uncommon
Treatment: emergent pericardiocentesis -subxiphoid approach, echo-guided. Drain as much as possible. Send fluid for cell count, protein, LDH, glucose, gram stain, culture, cytology, ADA.
🚨 Management
Acute Pericarditis -Treatment
Drug
Dose
Duration
Notes
NSAIDs 1ST LINE
Ibuprofen 600 mg PO TID or ASA 750–1000 mg PO TID
1–2 weeks, taper over 2–4 weeks
First-line anti-inflammatory. ASA preferred post-MI (NSAIDs impair scar formation). Add PPI for gastric protection.
Colchicine (Colcrys) ADD TO ALL
0.5 mg BID (if > 70 kg) or 0.5 mg daily (if ≤ 70 kg)
3 months
COPE, 2005 + ICAP, 2013: colchicine reduced recurrence by ~50%. Should be added to ALL pericarditis treatment. GI side effects (diarrhea). Renal dose if CrCl < 30.
Corticosteroids LAST RESORT
Prednisone 0.25–0.5 mg/kg/day
Taper over weeks–months
Avoid if possible -steroids increase recurrence rate. Use only if NSAIDs + colchicine contraindicated or failed, or autoimmune etiology confirmed. Taper VERY slowly.
Exercise restriction: Non-athletes → restrict until symptoms resolve + CRP normalizes. Athletes → minimum 3 months of no competitive sports ESC 2015 guidelines.
📋 On Rounds
Pimp Questions
Why do steroids increase recurrence in pericarditis?
Steroids suppress the immune response so effectively that the underlying viral/inflammatory process doesn't fully resolve -it smolders. When you taper the steroids, the inflammation rebounds. This is why COPE, 2005 and subsequent studies showed steroids as an independent predictor of recurrence. Colchicine, by contrast, modulates the inflammatory response without suppressing it entirely, leading to more durable resolution.
How do you differentiate pericardial effusion from tamponade?
Effusion is an anatomic finding. Tamponade is a hemodynamic diagnosis. A patient can have a massive chronic effusion with no hemodynamic compromise (the pericardium stretches slowly). Conversely, 200 mL accumulating rapidly (e.g., post-procedure, trauma, aortic dissection) can cause tamponade. The diagnosis is clinical: hypotension + JVD + pulsus paradoxus + echo showing diastolic chamber collapse.
When should you suspect cardiac tamponade in a patient with pericarditis?
Beck's triad: hypotension + JVD + muffled heart sounds (only 10-40% have all three). More reliable: pulsus paradoxus > 10 mmHg (SBP drops > 10 during inspiration). Best bedside test: echo showing diastolic RV collapse (most specific), RA collapse, IVC plethora (dilated, no respiratory variation), respiratory variation in mitral/tricuspid inflow velocities.
Why do you add colchicine to NSAIDs for pericarditis?
COPE, 2005 and ICAP, 2011: adding colchicine to NSAIDs halved the recurrence rate from ~30% to ~15%. Colchicine inhibits tubulin polymerization → blocks neutrophil chemotaxis and inflammasome activation. Dose: 0.5 mg BID (or 0.5 mg daily if < 70 kg) × 3 months for first episode, × 6 months for recurrence. Start colchicine on day 1 -not just for recurrence prevention.
Clinical Examples
📋 Case 1, Acute Viral Pericarditis with Myopericarditis
Patient: 26M, previously healthy, presents with 2 days of sharp pleuritic chest pain worse lying flat and improved leaning forward. Recent URI 10 days ago.
Key findings: T 100.4°F, HR 88, BP 122/74. Pericardial friction rub on auscultation. ECG: diffuse concave ST elevation + PR depression. Troponin 0.18 (mildly elevated). CRP 8.4. Echo: small circumferential effusion, no tamponade.
Management:
Ibuprofen 600 mg PO TID x 1-2 weeks, then taper by 200-400 mg/week. PPI for GI protection.
Colchicine 0.5 mg BID x 3 months (reduces recurrence by ~50%)
Activity restriction until symptoms resolved AND CRP normalized (critical with troponin elevation)
Repeat echo in 1 week; CRP weekly until normalized
Avoid steroids, increase recurrence risk
Teaching point: The mildly elevated troponin indicates myopericarditis (myocardial involvement). This does not change treatment but mandates strict exercise restriction, return to sport only after 3-6 months symptom-free with normal CRP, ECG, and echo. ICAP, 2013
📋 Case 2, Recurrent Pericarditis on Steroid Taper
Patient: 41F, 3rd episode of pericarditis in 18 months. Initially treated with NSAIDs alone (no colchicine). Second episode treated with prednisone 40 mg with rapid taper. Now recurs 2 weeks after completing steroid taper.
Key findings: Pleuritic chest pain, CRP 12.8, small effusion on echo. No tamponade physiology. ECG with recurrent ST changes.
Management:
Restart ibuprofen 600 mg TID + colchicine 0.5 mg BID x 6 months (longer duration for recurrence)
If steroid-dependent: very slow taper (decrease by 2.5 mg every 2-4 weeks only if asymptomatic + CRP normal)
If refractory to colchicine + NSAIDs + slow steroid taper: consider anakinra (IL-1 receptor antagonist)
Avoid exercise until CRP normalizes
Teaching point: Steroids are an independent risk factor for recurrent pericarditis. COPE, 2005 demonstrated colchicine should be first-line for all pericarditis. In steroid-dependent recurrent pericarditis, AIRTRIP, 2016 showed anakinra achieved complete response in 80%+ of patients.
📋 Case 3, Post-MI Pericarditis (Dressler Syndrome)
Patient: 63M, admitted 3 weeks ago for anterior STEMI with PCI to LAD. Now re-presents with pleuritic chest pain, low-grade fever, and new pericardial friction rub.
Key findings: ECG: diffuse ST elevation (different from prior focal anterior changes). Troponin re-elevated to 0.42. CRP 15.2. Echo: moderate pericardial effusion, no tamponade. On aspirin 81 mg + ticagrelor (DAPT).
Management:
Aspirin 750-1000 mg TID (preferred NSAID post-MI)
Colchicine 0.5 mg BID x 3 months
Avoid ibuprofen post-MI, interferes with aspirin's antiplatelet effect
Continue DAPT (do not stop ticagrelor for pericarditis)
Monitor for tamponade, anticoagulated patients at higher risk of hemorrhagic effusion
Teaching point: Dressler syndrome is autoimmune pericarditis occurring 2-10 weeks post-MI. Use aspirin (not ibuprofen) as the anti-inflammatory because ibuprofen competitively inhibits aspirin's irreversible COX-1 platelet binding. Avoid anticoagulation if large effusion due to hemorrhagic tamponade risk.
📣 Sample Presentation
One-Liner
"Mr. Okafor is a 24-year-old presenting with sharp pleuritic chest pain worse lying flat, improved leaning forward, following a URI 10 days ago. ECG shows diffuse ST elevation with PR depression. Troponin mildly elevated at 0.15 suggesting myopericarditis."
Key Points to Cover on Rounds
Etiology: likely viral (post-URI). Troponin 0.15 (mild, myopericarditis). Echo: small pericardial effusion, no tamponade physiology. CRP 8.4 (elevated, will trend). Treatment: ibuprofen 600 mg TID × 2 weeks + colchicine 0.5 mg BID × 3 months. Pain improving. Avoiding exercise until CRP normalizes and symptoms resolve. Plan: repeat echo in 1 week, CRP weekly.
Monitoring -Pericarditis & Pericardial Disease
Parameter
Frequency
Target / Action
CRP
Weekly until normal
Guides duration of therapy. Do NOT taper NSAIDs until CRP normalizes. Premature taper = recurrence.
ECG
At diagnosis, then at follow-up
Monitor ST/PR normalization through 4 stages. Persistent changes may suggest constrictive physiology.
TTE (Echo)
Repeat in 1-2 weeks
Confirm effusion resolution. Repeat sooner if hemodynamic compromise or clinical worsening.
RoundsRx Licensed Content - Unauthorized Use Prohibited💊 Medications
Medications -Pericarditis & Pericardial Disease
Drug
Dose
Duration
Notes
Ibuprofen (Advil) 1ST LINE
600 mg PO TID
1-2 weeks, then taper over 2-3 weeks
First-line NSAID. Take with PPI for GI protection. Taper by 200-400 mg/week.
Colchicine (Colcrys) 1ST LINE
0.5 mg BID (0.5 mg daily if <70 kg)
3 months (first episode), 6 months (recurrent)
Halves recurrence rate.COPE, 2005 + ICAP, 2013. GI side effects (diarrhea) -dose-reduce if needed.
Aspirin
750-1000 mg PO TID
1-2 weeks, then taper
Preferred over ibuprofen if recent MI (post-infarction pericarditis / Dressler syndrome).
Prednisone 2ND LINE ONLY
0.25-0.5 mg/kg/day
Slow taper over weeks-months
Only if contraindication to NSAIDs (renal failure, GI bleeding). Increases recurrence risk. Always use with colchicine.
Avoid anticoagulants if moderate-large effusion -risk of hemorrhagic pericardial effusion and tamponade. If on anticoagulation for other indication, discuss risk-benefit with cardiology.
⚡ Summary
Summary
Diagnose on Two of Four
Pleuritic chest pain, a pericardial friction rub, diffuse ST elevation with PR depression, and a new or worsening pericardial effusion.Any two make the diagnosis. The pain is classically sharp, worse lying flat and relieved by sitting forward, which is a useful discriminator from ischemic pain.
Separate It From STEMI on the ECG
Pericarditis: diffuse ST elevation across multiple territories, concave upward, with PR depression and no reciprocal change (except in aVR, where the ST depresses and the PR elevates).STEMI: territorial ST elevation, often convex, with reciprocal depression.Getting this wrong sends a pericarditis patient to the cath lab or, far worse, sends a STEMI patient home on ibuprofen.
Colchicine Is Not Optional
Add colchicine to the NSAID for 3 months: it roughly halves recurrence (ICAP, CORP). It is the single highest-yield element of the regimen and it is frequently omitted. Dose-reduce for renal impairment and for weight below 70 kg, and warn about diarrhea.
NSAIDs at Anti-Inflammatory Doses, Then Taper
High-dose ibuprofen or aspirin until symptoms resolve and CRP normalizes, then taper rather than stopping abruptly, which precipitates rebound. Use aspirin, not other NSAIDs, in post-MI pericarditis, because other NSAIDs impair infarct healing and increase the risk of wall rupture.
Avoid Steroids as First Line
Corticosteroids relieve symptoms quickly but substantially increase recurrence, creating a steroid-dependent course that is much harder to treat. Reserve them for specific indications: connective tissue disease, uremic pericarditis, or genuine NSAID and colchicine failure or contraindication.
Tamponade Is a Clinical Diagnosis
Not an echocardiographic one.A large chronic effusion can be entirely well tolerated, while a small, rapidly accumulating one causes tamponade, because the pericardium has not had time to stretch. Look for hypotension, raised JVP, muffled sounds, tachycardia and pulsus paradoxus, and treat with drainage, not diuretics.
Track CRP, and Restrict Exercise
CRP guides both the taper and the confirmation of resolution.Non-athletes: restrict until symptoms resolve and CRP normalizes. Athletes: a minimum of 3 months away from competitive sport (ESC), because exertion during active inflammation increases recurrence and arrhythmic risk.
Look for a Cause in the Minority Who Need It
Most acute pericarditis is viral or idiopathic and needs no workup beyond ECG, troponin, CRP, chest x-ray and echocardiography.Investigate further for high-risk features: fever above 38°C, subacute onset, a large effusion or tamponade, failure to respond after a week, immunosuppression, trauma or anticoagulation. Then consider tuberculosis, malignancy, uremia, autoimmune disease and bacterial pericarditis, and remember myopericarditis, where a raised troponin means myocardial involvement and warrants closer follow-up of ventricular function.
Tear in the aortic intima with blood tracking into the media. Stanford A (ascending) = surgical emergency with ~1% mortality per hour untreated. Stanford B (descending) = medical management unless complicated. HR and BP control are immediate priorities.
🔍 Overview
Stanford Classification
Type
Involvement
% of Cases
Mortality (Untreated)
Treatment
Stanford A
Ascending aorta (± descending)
~60%
~1–2% per hour for first 48h
Emergent surgery. Call CT surgery immediately. IRAD Registry, Hagan 2000
Stanford B
Descending aorta only (distal to L subclavian)
~40%
~10% at 30 days
Medical management (BP + HR control). Surgery/TEVAR only if complicated.
Any dissection involving the ascending aorta = Type A = surgery. It doesn't matter if it also extends into the descending aorta -ascending involvement dictates management.
Presentation
"Tearing" or "ripping" chest/back pain -acute onset, maximal at onset (unlike MI which crescendos), may migrate as dissection propagates
BP differential > 20 mmHg between arms -dissection flap compromising subclavian
Pulse deficit -absent or diminished pulses in one limb
Aortic regurgitation murmur (Type A -flap disrupts aortic valve)
Classic pitfall: Type A dissection involving the RCA → inferior STEMI on ECG. If you give tPA or anticoagulate for "MI," the patient bleeds into the pericardium → tamponade → death. Always consider dissection before treating STEMI, especially with tearing pain, pulse deficits, or widened mediastinum.
Diagnosis
Test
Role
CTA chest/abdomen/pelvis TEST OF CHOICE
Sensitivity > 95%. Shows intimal flap, true vs false lumen, extent, branch vessel involvement. Get with arterial phase + delayed phase.
TEE (transesophageal echo)
If too unstable for CT. Can be done at bedside / in OR. Excellent for Type A. Limited for distal descending.
CXR
Widened mediastinum (~60% sensitivity -absence does NOT rule out dissection). May see left pleural effusion.
D-dimer
Elevated in > 95% of dissections. Negative D-dimer has high NPV -can help rule out in low-pretest probability. Not reliable alone.
🚨 Management
Immediate -All Dissections
HR first, then BP. Dropping BP without slowing HR increases aortic wall shear stress (dP/dt) and propagates the dissection.
Step 1 -HR Control
IV beta-blocker first. Target HR < 60 bpm. Esmolol 500 mcg/kg bolus → 50–200 mcg/kg/min (preferred -ultra-short acting, titratable). Or labetalol 20 mg IV q10 min. Must control HR BEFORE adding vasodilators.
Step 2 -BP Control
Target SBP 100–120 mmHg. If BB alone insufficient → add nicardipine 5–15 mg/hr or nitroprusside 0.3–5 mcg/kg/min (only AFTER HR controlled). Clevidipine is another option (ultra-short acting CCB).
Pain Control
IV morphine or fentanyl. Pain drives sympathetic response → HR/BP elevation → propagation. Aggressive pain control is part of the treatment.
Type A -Surgical Emergency
Emergent CT surgery consult -do not delay for any reason
Mortality without surgery: 50% at 48h. With surgery: 15–25%.
Tamponade → emergent pericardiocentesis as bridge to OR (limited drainage -just enough to restore perfusion)
Type B -Medical Management
Uncomplicated Type B: BP/HR control + pain management + ICU monitoring. Long-term oral BB + amlodipine. Repeat imaging at 48–72h, 1 month, 6 months, then annually. INSTEAD-XL, Nienaber 2013ADSORB, Brunkwall 2014
Complicated Type B (malperfusion, rupture, refractory pain, rapid expansion) → TEVAR (thoracic endovascular aortic repair) or open surgery.
Medications
Drug (Brand)
Dose
Role
Esmolol (Brevibloc) 1ST LINE
500 mcg/kg bolus → 50–200 mcg/kg/min
Preferred BB -ultra-short t½ (9 min), highly titratable. Stops fast if complications.
Labetalol (Trandate) 1ST LINE
20 mg IV q10 min (max 300 mg) or 1–2 mg/min drip
α + β blocker. Good alternative if esmolol drip unavailable. Longer acting.
Nicardipine (Cardene) ADD-ON
5–15 mg/hr IV
Add if BP not at target despite BB. Do NOT use alone without BB.
Nitroprusside (Nipride) ADD-ON
0.3–5 mcg/kg/min
Potent vasodilator. Only use AFTER HR controlled -reflex tachycardia worsens shear stress. Cyanide toxicity > 48h.
📋 On Rounds
Why must you control HR before BP in aortic dissection?
dP/dt (the rate of rise of aortic pressure) is the primary driver of dissection propagation -not the absolute BP alone. Vasodilators (like nitroprusside) that drop BP without slowing HR cause reflex tachycardia, which paradoxically increases dP/dt and wall shear stress, potentially extending the dissection. Beta-blockers reduce both HR and contractility, lowering dP/dt. Always achieve HR < 60 first, then add vasodilators if needed for BP.
A patient presents with inferior STEMI and tearing chest pain radiating to the back. What should you think?
Type A aortic dissection involving the right coronary artery. The dissection flap can occlude the RCA ostium → inferior STEMI. If you give tPA, heparin, or dual antiplatelets for a "primary MI," the patient bleeds into the false lumen or pericardium → tamponade → death. Always consider dissection when STEMI presents with atypical features: tearing/migratory pain, pulse deficits, wide mediastinum, or new aortic regurgitation murmur.
Why is the target HR < 60 in aortic dissection, and why do you start a beta-blocker before a vasodilator?
HR and dP/dt (the rate of rise of aortic pressure) are the main determinants of aortic wall shear stress. The faster the heart beats and the harder it contracts, the more force is applied to the dissection flap → propagation. Beta-blockers reduce both HR and contractility (dP/dt) -esmolol IV is first-line (short-acting, titratable). You must start the BB BEFORE any vasodilator (e.g., nicardipine)
How do you differentiate Stanford Type A from Type B, and why does it change everything?
Type A: involves the ascending aorta (regardless of where the tear starts) → SURGICAL EMERGENCY. Mortality increases 1-2% per hour without surgery. Complications: aortic regurgitation, tamponade, coronary malperfusion (MI), stroke. Type B: involves only the descending aorta (distal to left subclavian) → medical management (HR/BP control). Surgery only if complicated (malperfusion, rupture, refractory pain, rapid expansion).
Clinical Examples
📋 Case 1, Type A Dissection with Tamponade
Patient: 58M, HTN and Marfan syndrome, presents with acute tearing chest pain radiating to back. Appears pale and diaphoretic.
Key findings: BP 180/110 right arm, 145/90 left arm (pulse deficit). HR 110. JVD, distant heart sounds, new diastolic murmur (AR). CTA: Stanford Type A dissection from aortic root to descending aorta. Pericardial effusion. Troponin elevated (RCA involvement).
Management:
Esmolol 500 mcg/kg bolus then drip, target HR < 60 FIRST
Then add nicardipine drip for SBP target < 120
EMERGENT cardiac surgery consult, Type A = surgical emergency (mortality 1-2%/hour without surgery)
Type and crossmatch 6 units pRBC, FFP, platelets available
Do NOT give tPA or anticoagulation despite troponin elevation (would be fatal)
Teaching point: Type A dissection with pericardial effusion = blood tracking into the pericardium. This patient has a triad of dissection + tamponade + aortic regurgitation. The inferior STEMI pattern is from RCA ostial involvement by the dissection flap. If sent to cath lab for "STEMI," the anticoagulation will be catastrophic.
📋 Case 2, Uncomplicated Type B Dissection
Patient: 64M, longstanding uncontrolled HTN (non-adherent), cocaine use. Presents with severe interscapular pain of sudden onset.
Key findings: BP 228/124, HR 96. No pulse deficits. Cr 1.3 (baseline). Lactate normal. CTA: Stanford Type B dissection from left subclavian to celiac trunk. No malperfusion.
Management:
Esmolol drip, HR to < 60 first, then nicardipine for SBP 100-120
IV morphine for pain control (pain drives sympathetic surge → worsens shear stress)
Uncomplicated Type B = medical management (HR/BP control)
Serial imaging (CTA in 48-72h, then 1, 3, 6, 12 months)
Transition to oral labetalol + amlodipine when stable x 24h on drip
Teaching point: Uncomplicated Type B dissection is managed medically. Surgery only if complicated: malperfusion, rupture, refractory pain, or rapid expansion. INSTEAD-XL, 2013 showed benefit of TEVAR for uncomplicated Type B only at 5 years, not acutely.
📋 Case 3, Type B with Mesenteric Malperfusion
Patient: 71F, HTN and DM2, initially managed medically for Type B dissection. 18 hours after admission, develops severe abdominal pain, bloody diarrhea, and rising lactate.
Key findings: Lactate 6.2 (was 1.1 on admission). Cr rising from 1.3 to 2.8. CT angiography: true lumen compression with SMA involvement. Absent bowel peristalsis.
Management:
This is NOW a complicated Type B, emergent intervention required
Vascular surgery / interventional radiology for TEVAR ± SMA stenting
Continue aggressive HR/BP control
NPO, NG tube, broad-spectrum antibiotics for possible bowel ischemia
Monitor for bowel necrosis (may require exploratory laparotomy if peritonitis develops)
Teaching point: Malperfusion syndrome converts uncomplicated to complicated Type B and mandates urgent intervention. Rising lactate + end-organ dysfunction in a patient with known dissection should trigger immediate reimaging and surgical/IR consultation. Mesenteric ischemia from dissection carries mortality > 50% without intervention.
📣 Sample Presentation
One-Liner
"Mr. Franklin is a 62-year-old with longstanding uncontrolled HTN presenting with acute tearing chest pain radiating to the back. BP 210/120 in right arm, 168/95 in left. CTA shows Stanford type B aortic dissection extending from left subclavian to celiac trunk."
Key Points to Cover on Rounds
Stanford type B (descending) -medical management. HR 58 on esmolol drip (target <60). SBP 118 on nicardipine drip (target 100-120). No malperfusion signs: renal function stable, bowels functioning, distal pulses symmetric. CT surgery aware -no surgical indication currently. Pain controlled with IV morphine. Plan: transition to oral BB + amlodipine when stable ×24h, serial imaging.
Monitoring -Aortic Dissection
Arterial line -continuous BP monitoring mandatory. SBP target 100-120 mmHg.
HR q5-15 min during drip titration. Target HR <60 bpm.
Urine output hourly -renal malperfusion if declining.
HR first, THEN BP. Always achieve heart rate control before adding vasodilators. Pure vasodilators without beta-blockade cause reflex tachycardia, increasing aortic shear stress and propagating the dissection.
Add AFTER beta-blocker for SBP target <120 mmHg. Smooth arterial vasodilator. No reflex tachycardia when BB already on board.
Labetalol (Trandate) ALTERNATIVE
20 mg IV bolus, then 1-2 mg/min drip
IV
Combined alpha + beta blockade. Alternative to esmolol + nicardipine. Less titratable than esmolol.
Nitroprusside ADJUNCT ONLY
0.25-10 mcg/kg/min
IV
NEVER without prior beta-blockade. Potent vasodilator -reflex tachycardia worsens dissection. Cyanide toxicity risk with prolonged use.
IV Morphine
2-4 mg IV q5-15min PRN
IV
Pain control is critical -pain drives sympathetic surge → elevated HR/BP. Reduces shear stress.
Avoid: pure vasodilators (hydralazine, nitroprusside) without beta-blockade. Avoid anticoagulation until dissection is excluded or surgical plan is defined.
⚡ Summary
Summary
Type A
Ascending aorta involved → SURGICAL EMERGENCY. Mortality 1-2%/hr without surgery. Call CT surgery immediately.
Type B
Descending only → Medical management. HR < 60 + SBP 100-120. Surgery only if complicated (malperfusion, rupture).
First Drug
Esmolol IV (BB before vasodilator). Reduce HR first, then BP. Vasodilators alone → reflex tachycardia → worsens dissection.
Imaging
CTA chest/abdomen/pelvis. If CTA unavailable → TEE. CXR may show widened mediastinum but is insensitive.
Suspect When
Tearing chest/back pain + BP differential between arms + unequal pulses + history of HTN or Marfan.
Infection of the endocardial surface (usually valves). Diagnosis requires high clinical suspicion + blood cultures + echo. Delay in treatment = valve destruction, emboli, death. Get cultures before antibiotics -then don't wait.
🔍 Overview
Modified Duke Criteria
Definite IE: 2 major, OR 1 major + 3 minor, OR 5 minor. Possible IE: 1 major + 1 minor, OR 3 minor. Modified Duke, 2000
Major Criteria
Details
1. Positive blood cultures
Typical organisms from 2 separate cultures: Viridans strep, S. bovis, HACEK, S. aureus, or Enterococcus (without primary focus). OR persistently positive cultures (≥ 2 drawn > 12h apart, or 3/3 or majority of ≥ 4 cultures positive).
2. Endocardial involvement
Echo: vegetation, abscess, new prosthetic dehiscence. OR new valvular regurgitation (murmur change).
Minor Criteria
Predisposition: IV drug use, prosthetic valve, prior IE, structural heart disease
Microbiologic: positive cultures not meeting major criteria, or serologic evidence
Blood Culture Protocol
3 sets of blood cultures from 3 different venipuncture sites before antibiotics. Each set = 1 aerobic + 1 anaerobic bottle. Draw at least 20 mL per set. Space 30–60 min apart if possible (but do NOT delay antibiotics more than 1–2h for critically ill patients).
Organisms
Organism
% of IE
Key Association
S. aureus
~30–40%
Most common overall (especially IVDU and healthcare-associated). Acute, destructive. High embolic risk.
Viridans streptococci
~20–25%
Subacute. Dental procedures. Native valve. More indolent course.
Vancomycin (Vancocin) (covers MRSA -most common in IVDU IE)
Narrow to nafcillin/oxacillin if MSSA. Right-sided (tricuspid) has better prognosis than left-sided. POET, 2019
🔄 Updated Practice: Old teaching: add gentamicin to all endocarditis regimens for synergy. Current practice: gentamicin is no longer routinely recommended for native valve Staph aureus endocarditis, it adds nephrotoxicity without mortality benefit. For Enterococcus faecalis endocarditis, ampicillin + ceftriaxone is preferred over ampicillin + gentamicin (equally effective, less nephrotoxic, Enterococcal Endocarditis Trial, 2013). Gentamicin is still used for prosthetic valve endocarditis and some streptococcal regimens.
Surgical Indications -When to Operate
Early surgery (during initial hospitalization) reduces mortality in these scenarios:[EASE, 2012
Heart failure from severe valvular regurgitation -most common surgical indication
Large vegetation (> 10 mm) with embolic events despite antibiotics
Fungal endocarditis -almost always requires surgery
Prosthetic valve endocarditis with dehiscence, abscess, or persistent bacteremia
S. aureus prosthetic valve IE -consider early surgery regardless
📋 On Rounds
Why does S. bovis endocarditis require a colonoscopy?
S. gallolyticus (formerly S. bovis biotype I) bacteremia/endocarditis has a strong association with colorectal malignancy -up to 25–50% of patients have colon polyps or cancer. The mechanism is thought to involve bacterial translocation through disrupted colonic mucosa. Every patient with S. bovis/gallolyticus bacteremia needs a colonoscopy, even if asymptomatic.
When do you get a TEE vs TTE for endocarditis?
TTE first in most patients -sensitivity ~70% for vegetations. If TTE is negative but clinical suspicion remains high → TEE (sensitivity ~95%). Go straight to TEE in: prosthetic valves (TTE limited by acoustic shadowing), suspected perivalvular abscess, S. aureus bacteremia (high-risk, need definitive imaging), poor TTE windows (obese, ventilated). If initial TTE/TEE negative but suspicion persists → repeat in 5–7 days.
When does endocarditis require surgery instead of antibiotics alone?
Four major surgical indications: (1) Heart failure from valvular regurgitation (most common indication), (2) Uncontrolled infection (persistent bacteremia > 7 days despite appropriate abx, perivalvular abscess, mycotic/fungal endocarditis), (3) Large vegetation (> 10 mm on left-sided valve with embolic event, or > 15 mm even without embolism), (4) Prosthetic valve endocarditis with any of the above.
A patient with IVDU has tricuspid valve endocarditis. Does this change your antibiotic approach?
Right-sided endocarditis (TV) in IVDU has better prognosis than left-sided (mortality ~5% vs ~20-30%). If MSSA: nafcillin/oxacillin 2g IV q4h × 4 weeks (can shorten to 2 weeks if: uncomplicated, MSSA, no metastatic infection, vegetation < 2 cm, and clinical improvement). MRSA: vancomycin or daptomycin (daptomycin is an alternative for right-sided MRSA IE, but NOT left-sided -inactivated by surfactant in lungs).
Clinical Examples
📋 Case 1, Native Valve Endocarditis with Embolic Stroke
Patient: 58M with poorly controlled diabetes, presents with 3 weeks of fevers, malaise, and new-onset left arm weakness. Recent dental extraction 4 weeks ago without antibiotic prophylaxis.
Key findings: Temp 38.9°C, HR 105, new aortic regurgitation murmur, Janeway lesions on palms, splinter hemorrhages. Blood cultures 4/4 positive for Streptococcus gallolyticus. TEE: 1.4 cm vegetation on aortic valve with moderate AR. MRI brain: acute embolic infarct R MCA territory.
Management:
IV penicillin G 4 million units q4h + gentamicin 1 mg/kg q8h (synergy) x 4 weeks
Urgent CT surgery consult: large vegetation (>10 mm) + embolic event = surgical indication EASE Trial, 2012
Colonoscopy required: S. gallolyticus (bovis) has strong association with colorectal neoplasia (~60% have polyps or cancer)
Serial blood cultures q48h until clearance; repeat TEE at 1 week
Teaching point: S. gallolyticus endocarditis mandates colonoscopy regardless of GI symptoms. Embolic events with vegetations >10 mm warrant early surgery.
📋 Case 2, Prosthetic Valve Endocarditis with Paravalvular Abscess
Patient: 72F with mechanical aortic valve (replaced 8 months ago), presents with fever x 2 weeks, chills, and new heart failure symptoms. Central line placed 3 weeks ago for chemotherapy.
Key findings: Temp 38.5°C, HR 98, BP 100/55, bilateral crackles, JVD. Blood cultures 4/4 positive for methicillin-resistant Staphylococcus epidermidis. TEE: 8 mm vegetation on prosthetic AV, paravalvular abscess with new dehiscence.
Management:
Vancomycin (trough 15-20) + rifampin 300 mg PO q8h + gentamicin 1 mg/kg IV q8h x 2 weeks, then vanco + rifampin x 6 weeks total
Heart failure management: diuresis, preload/afterload optimization while awaiting surgery
Rifampin added ONLY after blood cultures negative (induces resistance if started during active bacteremia)
Teaching point: PVE with paravalvular abscess has near-100% surgical indication. Rifampin is essential for biofilm penetration on prosthetic material but must be started after culture clearance.
📋 Case 3, Culture-Negative Endocarditis
Patient: 38F, no significant PMH, presents with 6 weeks of fevers, weight loss, arthralgias, and night sweats. Given azithromycin empirically 2 weeks ago at urgent care.
Key findings: Temp 38.2°C, new MR murmur, Osler nodes on fingertips. Blood cultures 4/4 negative (drawn on antibiotics). TTE: 6 mm vegetation on anterior mitral leaflet. Bartonella henselae IgG titer 1:1024. Patient has 3 cats.
Bartonella IE confirmed: doxycycline 100 mg BID + gentamicin 1 mg/kg q8h x 2 weeks, then doxycycline alone x 6 weeks
Prior antibiotic exposure is the most common cause of culture-negative IE (~50% of cases)
Consider 16S rRNA PCR on excised valve tissue if serologies inconclusive
Teaching point: When cultures are negative, always ask about prior antibiotics. Bartonella is the most common cause of culture-negative IE in immunocompetent patients -- think cat exposure.
📣 Sample Presentation
One-Liner
"Mrs. Thompson is a 44-year-old with IVDU presenting with 2 weeks of fever, chills, and a new systolic murmur at the left sternal border. Blood cultures grew MSSA (4/4 bottles). TTE shows a 1.2 cm vegetation on the tricuspid valve."
Key Points to Cover on Rounds
Organism: MSSA on 4/4 blood cultures, sensitive to oxacillin. Antibiotics: nafcillin 2g IV q4h, day 5 of planned 6-week course. Echo: 1.2 cm TV vegetation, moderate TR, no abscess. No embolic complications -CT chest negative for septic emboli, UA clean. Surveillance cultures at 48h negative. ID following. CT surgery evaluated -no surgical indication yet. Plan: PICC line placed, continue IV abx, daily assessment for embolic events.
Monitoring During Treatment
Parameter
Frequency
Target / Action
Blood cultures
q24-48h until negative
Must document clearance. Persistent bacteremia → evaluate for abscess, source control
Aminoglycosides and vancomycin are nephrotoxic. Adjust doses accordingly
CBC, ESR/CRP
Weekly
Trend WBC and inflammatory markers. Should decline with treatment
Repeat TTE/TEE
At completion of therapy
New baseline. Sooner if clinical deterioration, new murmur, or concern for abscess
Neuro checks
Daily
Embolic stroke in 20-40%. New focal deficit → urgent CT/MRI head
ECG
Daily initially
New PR prolongation → perivalvular abscess. New AV block is an emergency
New conduction abnormality (prolonged PR, new heart block) during IE = abscess until proven otherwise. Get urgent TEE and CT surgery consult.
🧪 Workup
Diagnostic Evaluation -Infective Endocarditis
Blood cultures BEFORE antibiotics. Obtain 3 sets from separate venipuncture sites, separated by at least 30 minutes. This is the single most important diagnostic step.
Test
Findings
Clinical Significance
Blood cultures ×3 ESSENTIAL
Persistent bacteremia (same organism in multiple sets)
Draw from 3 separate sites BEFORE antibiotics. Continuous bacteremia is a major Duke criterion. Identifies organism + susceptibilities.
Anemia of chronic disease common in subacute IE. Thrombocytopenia suggests severe sepsis or DIC.
BMP
Cr (baseline + immune complex GN), electrolytes
Renal function -immune complex glomerulonephritis, aminoglycoside toxicity monitoring.
ESR / CRP
Elevated
Markers of inflammation. Trend to monitor treatment response.
Rheumatoid factor
Elevated in chronic IE
Minor Duke criterion. Immune complex formation in subacute endocarditis.
Complement levels (C3/C4)
Low
Consumed by immune complex deposition (glomerulonephritis).
Urinalysis
Microscopic hematuria, RBC casts, proteinuria
Immune complex GN or renal septic emboli. Hematuria in up to 50% of IE patients.
Modified Duke Criteria: Definite IE = 2 major, OR 1 major + 3 minor, OR 5 minor criteria. Major: (1) positive blood cultures (typical organism ×2, or persistently positive), (2) endocardial involvement on echo (vegetation, abscess, new dehiscence, new regurgitation).
💊 Medications
Key Medications -Infective Endocarditis
Scenario
Regimen
Duration
Notes
Empiric (native valve)
Vancomycin (AUC 400-600) + Ceftriaxone (Rocephin) 2g IV q24h
Anti-staphylococcal penicillins are preferred over vancomycin for MSSA (better outcomes). Cefazolin 2g IV q8h if penicillin allergy (non-anaphylactic).
MRSA -native valve
Vancomycin IV, AUC-guided dosing (target AUC 400-600)
6 weeks
Trough-based dosing is outdated. AUC-guided dosing reduces nephrotoxicity. Alternative: daptomycin 8-10 mg/kg IV daily (NOT for left-sided endocarditis with pulmonary involvement -inactivated by surfactant).
Prosthetic valve (empiric)
Vancomycin + Gentamicin 1 mg/kg IV q8h + Rifampin 300 mg PO q8h
≥6 weeks (vanco + rifampin), 2 weeks (gent)
Rifampin penetrates biofilm on prosthetic material. Do NOT start rifampin until blood cultures are negative (resistance develops rapidly).
Viridans streptococci (MIC ≤0.12)
Ceftriaxone 2g IV q24h
4 weeks
Can use 2-week short course with ceftriaxone + gentamicin if uncomplicated native valve. Penicillin G 12-18 million units/day IV continuous is alternative.
Enterococcus
Ampicillin 2g IV q4h + Ceftriaxone 2g IV q12h
6 weeks
Ampicillin + ceftriaxone preferred over ampicillin + gentamicin (avoids nephrotoxicity, similar efficacy). If VRE: linezolid or daptomycin.
Surgical indications: heart failure from valvular dysfunction, uncontrolled infection (persistent bacteremia >5-7 days, abscess, enlarging vegetation), prevention of embolism (vegetation >10 mm with embolic event, >15 mm regardless). Consult CT surgery early.
⚡ Summary
Summary
Modified Duke
2 major, or 1 major + 3 minor, or 5 minor. Major: positive blood cultures (typical organisms), echo vegetation.
ESR/CRP: Elevated in > 90%. Useful for monitoring treatment response
Urinalysis: Microscopic hematuria (renal emboli, immune complex GN) in 25-50%
RF (rheumatoid factor): Positive in ~50% of subacute IE
Procalcitonin: Supports bacterial etiology if elevated
Imaging
TTE first -sensitivity ~75% for native valves. Adequate if high quality and clinical picture clear
TEE if: TTE negative but high suspicion, prosthetic valve, poor TTE windows, suspected abscess/fistula. Sensitivity ~95%
CT chest/abdomen/pelvis: If concern for septic emboli (splenic infarct, renal infarct, mycotic aneurysm)
Brain MRI: If neurologic symptoms. Mycotic aneurysms, septic emboli, meningitis
PET/CT: Consider for prosthetic valve IE or cardiac implantable device infection when echo is equivocal
Modified Duke Criteria: 2 major, or 1 major + 3 minor, or 5 minor = definite IE. Major = positive blood cultures (typical organism × 2 OR persistently positive) + endocardial involvement on echo (vegetation, abscess, new dehiscence, new regurgitation).
Vancomycin 15-20 mg/kg IV q8-12h (trough 15-20) OR daptomycin 8-10 mg/kg IV daily
Vancomycin + rifampin + gentamicin × 2 weeks
6 weeks
Viridans Strep (MIC ≤ 0.12)
Ceftriaxone 2g IV daily OR penicillin G 12-18 MU/day
Same + gentamicin × 2 weeks
NV: 4 weeks. PV: 6 weeks
Enterococcus
Ampicillin 2g IV q4h + ceftriaxone 2g IV q12h (preferred for E. faecalis)
Ampicillin + ceftriaxone 6 weeks
6 weeks
HACEK
Ceftriaxone 2g IV daily
Ceftriaxone 2g IV daily
NV: 4 weeks. PV: 6 weeks
Culture-negative
Vancomycin + cefepime. ID consult for serologies (Bartonella, Coxiella, Brucella)
Same + rifampin
6 weeks
Key principles: Bactericidal agents only (not bacteriostatic). IV therapy for entire course. Aminoglycoside synergy duration varies. Monitor vanco troughs, gentamicin levels, renal function. ID consult for all IE.
⚡ Summary
Cultures Before Antibiotics, Then Do Not Wait
Three sets of blood cultures from separate sites, ideally spaced, before the first antibiotic dose.Antibiotics given first cause culture-negative endocarditis, which turns a 6-week targeted regimen into months of guesswork. In sepsis or acute deterioration, take the cultures fast and start empiric therapy immediately; do not delay for spacing.
Use the Modified Duke Criteria
Major: typical organism in persistently positive cultures, and evidence of endocardial involvement on echo (vegetation, abscess, new dehiscence) or a new regurgitant murmur.Minor: predisposing condition or injection drug use, fever, vascular phenomena, immunologic phenomena, and supportive microbiology.Definite is 2 major, or 1 major plus 3 minor, or 5 minor.
TTE First, but a Negative TTE Does Not Exclude It
Transthoracic echo is the starting point and is quick and non-invasive.TEE is far more sensitive and is required for a prosthetic valve, when abscess is suspected, and whenever suspicion remains after a negative TTE. Going home on a negative TTE with persistent bacteremia is a recognized way to miss this diagnosis.
Let the Organism Tell You Where to Look
S. aureus: acute, aggressive, destroys valves quickly, and is the commonest overall including in injection drug use (classically tricuspid).Viridans streptococci: subacute, after dental procedures.Enterococcus: genitourinary source.S. gallolyticus (bovis): get a colonoscopy, because of its association with colorectal neoplasia. Coagulase-negative staphylococci: prosthetic valves.
Empiric Therapy Then Narrow
Vancomycin covers MRSA and streptococci for a native valve; add gentamicin and rifampin for a prosthetic valve.Narrow as soon as susceptibilities return, since targeted therapy is more effective and less toxic. Treat for 4 to 6 weeks, with the clock usually starting from the first negative blood culture.
Know the Surgical Indications
Heart failure from valve dysfunction (the commonest and most urgent), perivalvular abscess or heart block, persistent bacteremia beyond 5 to 7 days of appropriate therapy, fungal or highly resistant organisms, recurrent emboli with a persisting large vegetation, and prosthetic valve endocarditis.Refer early rather than after the patient decompensates: operating on established heart failure carries far higher mortality.
Look for Complications Actively
Embolic stroke, mycotic aneurysm, splenic and renal infarcts, vertebral osteomyelitis and septic pulmonary emboli in right-sided disease.Image the brain in any neurologic symptom, and consider whole-body imaging in S. aureus bacteremia.Peripheral stigmata (Janeway lesions, Osler nodes, Roth spots, splinter hemorrhages) are uncommon now, so their absence means nothing.
Get Prophylaxis Right, Because It Narrowed
Only the highest-risk patients need antibiotic prophylaxis: prosthetic valves or prosthetic material, previous endocarditis, certain congenital heart disease, and cardiac transplant valvulopathy. Only for dental procedures involving gingival or periapical manipulation, plus certain respiratory and infected-skin procedures. Mitral valve prolapse and bicuspid aortic valve no longer qualify, and routine GI and GU procedures do not warrant it.
Aortic stenosis, mitral regurgitation, and aortic regurgitation -the three you'll see most. Know the murmurs, when to echo, and when to refer for intervention.
🔍 Overview
Jump to:ASMRARMSTRMurmursEcho
Aortic Stenosis
Severity
Parameter
Mild
Moderate
Severe
Aortic valve area (AVA)
> 1.5 cm²
1.0–1.5 cm²
< 1.0 cm²
Mean gradient
< 20 mmHg
20–40 mmHg
> 40 mmHg
Peak velocity
< 3 m/s
3–4 m/s
> 4 m/s
When to Intervene
Symptomatic severe AS: any symptom from the classic triad → immediate referral for AVR
Classic triad (SAD):S yncope (3-year survival without AVR) · A ngina (5-year) · D yspnea/HF (2-year). Once symptoms develop, mortality is 50% at 2 years without surgery.
Asymptomatic severe AS with EF < 50% → AVR
TAVR (transcatheter) now approved for all surgical risk categories PARTNER 3, 2019
⚠️ Avoid vasodilators in severe AS. Afterload reduction (nitrates, ACEi, hydralazine) can cause severe hypotension -the fixed obstruction prevents compensatory increase in CO. Also avoid rapid fluid depletion -AS patients are preload-dependent.
Wide (bounding "water-hammer" pulse, Corrigan pulse, de Musset sign)
Murmur
Short early diastolic (equalization)
Blowing early diastolic at LUSB, best heard sitting up and leaning forward
Treatment
Emergent surgery. Nitroprusside bridge. IABP is CONTRAINDICATED in AR.
Surgery when symptomatic, or asymptomatic with EF < 55% or LVESD > 50 mm or LVIDd > 65 mm.
⚠️ IABP is contraindicated in aortic regurgitation. The balloon inflates in diastole -this increases aortic diastolic pressure and worsens regurgitant flow back into the LV.
Mitral Stenosis
Feature
Details
#1 Cause
Rheumatic heart disease (virtually always). Rare in developed countries now.
Pathophysiology
Stenotic MV → ↑ LA pressure → LA dilation → atrial fibrillation → pulmonary HTN → RV failure
Murmur
Low-pitched diastolic rumble at apex with opening snap. Best heard in left lateral decubitus. Shorter snap-to-rumble interval = more severe.
Key complication
Afib (from LA dilation) → high stroke risk → anticoagulate with warfarin (DOACs inferior in mechanical/rheumatic valvular disease)
Severity
Normal MVA ~4–6 cm². Severe MS: MVA < 1.5 cm², mean gradient > 10 mmHg
Treatment
Rate control (BB/CCB) + anticoagulation if Afib. Intervention: percutaneous mitral balloon commissurotomy (PMBC) if pliable valve, no significant MR, no LA thrombus. Otherwise → surgical MV replacement.
Tricuspid Regurgitation
Feature
Details
#1 Cause
Functional/secondary -RV dilation from pulmonary HTN, LV failure, or COPD stretches the tricuspid annulus
Treat the underlying cause (pulmonary HTN, LV failure). Diuretics for volume overload. Surgery rarely needed unless primary TR with severe symptoms.
Murmur Quick Reference
Lesion
Murmur
Timing
Best Heard
Key Maneuver
Aortic Stenosis
Crescendo-decrescendo (ejection)
Systolic
RUSB → carotids
↓ with Valsalva (except HCM)
Mitral Regurgitation
Holosystolic (blowing)
Systolic
Apex → axilla
↑ with handgrip (↑ afterload)
Aortic Regurgitation
Early diastolic (blowing, decrescendo)
Diastolic
LUSB, sitting up/leaning forward
Wide pulse pressure, water-hammer pulse
Mitral Stenosis
Low-pitched rumble with opening snap
Diastolic
Apex, left lateral decubitus
Louder with exercise (↑ flow)
Tricuspid Regurgitation
Holosystolic (blowing)
Systolic
LLSB
↑ with inspiration (Carvallo sign)
When to Get an Echo
New murmur with symptoms (dyspnea, syncope, chest pain)
Any diastolic murmur (always pathologic)
Any holosystolic murmur (MR or TR)
Grade ≥ 3/6 systolic murmur
Systolic murmur + abnormal symptoms/exam findings
Known valve disease with change in symptoms
Benign flow murmurs (grade 1–2/6 systolic at LUSB, no radiation, no symptoms, young patient) do NOT need echo. But when in doubt -echo.
📋 On Rounds
What is the classic triad of symptomatic aortic stenosis?
SAD: Syncope, Angina, Dyspnea (HF). They appear in that order as the disease progresses. Once any symptom develops, average survival without AVR: syncope = 3 years, angina = 5 years, heart failure = 2 years. This is why symptomatic severe AS is an indication for urgent valve replacement -delay costs lives.
Why is IABP contraindicated in aortic regurgitation?
The IABP inflates during diastole to augment coronary perfusion and deflates during systole to reduce afterload. In AR, blood regurgitates from aorta into LV during diastole. IABP inflation during diastole increases aortic diastolic pressure → drives MORE blood backward through the incompetent valve → worsens regurgitation and LV volume overload. Use nitroprusside or Impella instead for hemodynamic support in acute AR.
A patient with severe aortic stenosis needs non-cardiac surgery. How do you manage this?
Severe AS + non-cardiac surgery = high perioperative risk (hypotension, HF, death). Key principles: (1) Symptomatic severe AS → defer elective surgery until valve intervention (TAVR or SAVR). (2) If surgery is urgent/emergent: proceed with invasive hemodynamic monitoring, maintain preload (avoid dehydration), avoid vasodilators and rapid HR changes, goal-directed fluid management
What is the most important echo measurement in aortic stenosis and what values define severe?
Aortic valve area (AVA) is the gold standard. Severe AS: AVA < 1.0 cm², mean gradient > 40 mmHg, peak velocity > 4 m/s. BUT these can be discordant in low-flow, low-gradient AS (low EF → low gradient despite severe stenosis). In this case, do a dobutamine stress echo: if AVA remains < 1.0 cm² as flow increases → truly severe ("fixed" stenosis → valve intervention). If AVA improves → pseudosevere (improve EF medically).
Clinical Examples
📋 Case 1, Symptomatic Severe Aortic Stenosis
Patient: 76M with progressive dyspnea on exertion and an episode of exertional syncope. Crescendo-decrescendo systolic murmur at RUSB radiating to carotids. Echo: AVA 0.6 cm², mean gradient 48 mmHg, peak velocity 4.5 m/s, EF 55%.
Key findings: Symptomatic severe AS (SAD triad: Syncope, Angina, Dyspnea). Once symptoms develop, mortality without intervention: syncope = 3-year, angina = 5-year, HF = 2-year median survival.
Management:
Immediate referral for aortic valve replacement, do NOT delay
Heart team discussion: TAVR vs SAVR. TAVR now approved for all surgical risk categories PARTNER 3, 2019
TAVR preferred if: age > 65, high surgical risk, no bicuspid valve. SAVR preferred if: age < 50, bicuspid, concomitant CABG needed
AVOID vasodilators (ACEi/nitrates) and excessive diuresis, fixed obstruction means preload-dependent
No balloon valvuloplasty as definitive therapy (restenosis in weeks), only as bridge to TAVR/SAVR
Teaching point: Symptomatic severe AS is a surgical emergency, median survival without intervention is 2-5 years depending on symptoms. There is no effective medical therapy for AS. The only treatment is valve replacement.
📋 Case 2, Acute Severe Mitral Regurgitation
Patient: 62M, 3 days post-inferior STEMI. Sudden dyspnea, new holosystolic murmur radiating to axilla, flash pulmonary edema. BP 85/50. Echo: EF 50%, flail posterior MV leaflet, severe eccentric MR jet. BNP 4200.
Key findings: Acute severe MR from papillary muscle rupture post-MI. The posteromedial papillary muscle (single blood supply from PDA) is vulnerable in inferior MI. This is a surgical emergency, mortality without surgery approaches 75% at 24h.
Management:
Emergent cardiac surgery consult for MV repair or replacement
Afterload reduction: nitroprusside or IV nitroglycerin (reduces regurgitant fraction by lowering SVR)
IABP for hemodynamic stabilization as bridge to OR (reduces afterload during systole → reduces MR)
Teaching point: Acute severe MR is a volume + pressure emergency. The LV has not had time to dilate and compensate. Unlike chronic MR (where EF can be preserved for years), acute MR → immediate pulmonary edema and shock. Surgery is the only definitive treatment.
📋 Case 3, Mitral Stenosis with New Atrial Fibrillation
Patient: 42F immigrant from South Asia with progressive dyspnea, now palpitations. HR 142 irregularly irregular, bilateral rales. Echo: MVA 1.1 cm² (moderate-severe MS), LA diameter 5.8 cm, RV pressure 55 mmHg. No MV thrombus on TEE.
Key findings: Rheumatic mitral stenosis with new Afib. MS increases LA pressure → LA dilation → Afib. Afib causes loss of atrial kick + rapid rate → dramatically worsened hemodynamics. MS + Afib = high stroke risk (warfarin required, not DOACs).
Management:
Rate control with IV diltiazem or beta-blocker, slower HR = longer diastolic filling time through stenotic valve
IV furosemide for pulmonary congestion (MS causes pulmonary venous HTN)
Anticoagulation with warfarin (NOT DOACs, valvular AF from MS requires warfarin, INR 2-3)
Once stable: percutaneous mitral balloon commissurotomy (PMBC) if valve morphology favorable (Wilkins score ≤ 8)
If PMBC not feasible: surgical MV repair or replacement
Teaching point: Mitral stenosis with Afib is the ONE scenario where warfarin is mandatory over DOACs. DOACs have not been studied in rheumatic MS. Rate control is more important than rhythm control, slow rates improve diastolic filling through the stenotic valve.
📣 Sample Presentation
One-Liner
"Mr. Morris is a 78-year-old presenting with exertional syncope and progressive dyspnea. Echo shows severe aortic stenosis with AVA 0.7 cm², mean gradient 52 mmHg, EF 55%. Symptomatic severe AS."
Key Points to Cover on Rounds
Symptomatic severe AS (syncope + dyspnea). AVA 0.7, mean gradient 52, EF preserved. STS score 4.2% (intermediate risk). CT surgery and structural heart consulted -candidate for TAVR vs SAVR discussion. Medical optimization: gentle diuresis for volume overload. Avoiding vasodilators and aggressive diuresis. Plan: outpatient TAVR evaluation, cardiac cath to assess coronary anatomy.
🧪 Workup
Diagnostic Evaluation -Valvular Heart Disease
Echo is the cornerstone. Every suspected valvular lesion needs echocardiography for severity grading. Additional testing depends on the clinical context and surgical candidacy.
Drug: Amoxicillin 2g PO 30–60 min before procedure. If PCN allergy: clindamycin 600mg PO or azithromycin 500mg PO.
⚡ Summary
Summary
Echo Is the Cornerstone
Every suspected valvular lesion needs echocardiography for severity grading.A benign flow murmur, grade 1 to 2 out of 6, systolic, at the left upper sternal border, with no radiation and no symptoms in a young patient, does not need an echo, but anything diastolic, anything with symptoms, and anything you are unsure about does.
Aortic Stenosis: Symptoms Are the Trigger
Severe is a valve area below 1.0 cm², a mean gradient above 40 mmHg, or a peak velocity above 4.0 m/s.Asymptomatic severe AS has near-normal survival; the appearance of angina, syncope or heart failure means refer for valve replacement now.Nothing medical alters the natural history.
Do Not Vasodilate Severe AS
Nitrates, ACE inhibitors and hydralazine can cause profound hypotension, because the fixed obstruction prevents a compensatory rise in cardiac output. Equally, avoid rapid fluid depletion: these patients are preload-dependent. Both errors present as sudden collapse in a patient who was stable an hour earlier.
Aortic Regurgitation: Operate on the Ventricle
Symptoms, or an EF below 55%, or an end-systolic dimension above 50 mm, or an end-diastolic dimension above 65 mm.The ventricle dilates silently for years, and once it decompensates the recovery after surgery is incomplete, which is why the echo dimensions matter as much as the symptoms. Acute severe AR, from dissection or endocarditis, is a surgical emergency with no time for medical management.
IABP Is Contraindicated in Aortic Regurgitation
The balloon inflates in diastole, which raises aortic diastolic pressure and drives more blood back into the ventricle. It worsens exactly the lesion it is being used to support. This is a classic and dangerous error in a hypotensive patient with an unrecognized AR murmur.
Mitral Regurgitation: Read the EF Differently
In MR the ventricle unloads into the low-pressure left atrium, so the EF is falsely flattering.An EF of 60% in severe MR is already impaired, which is why the surgical threshold is EF 60% or below, or an end-systolic dimension of 40 mm or more, even without symptoms. Separate primary (degenerative, valve problem, operate) from secondary (functional, ventricular problem, optimize guideline therapy first).
Mitral Stenosis Is Almost Always Rheumatic
An opening snap with a diastolic rumble, and atrial fibrillation from left atrial enlargement.Rate control is the key medical intervention, because tachycardia shortens diastole and is what causes decompensation, classically in pregnancy or with new AF. Percutaneous balloon valvuloplasty is effective in suitable anatomy, unlike in aortic stenosis where it is only a bridge.
Follow Asymptomatic Disease on a Schedule
Severe lesions need annual echocardiography; moderate every 1 to 2 years; mild every 3 to 5.Teach the patient which symptoms mean 'come back now', since the entire management strategy depends on catching the transition to symptomatic disease. Refer to a Heart Valve Team for intervention decisions, and remember endocarditis prophylaxis now applies only to the highest-risk groups.
Transient loss of consciousness from cerebral hypoperfusion. The key question: is this cardiac or benign? Risk-stratify every patient -most syncope is vasovagal, but cardiac syncope kills.
🔍 Overview
Definition & Classification
Syncope = transient loss of consciousness (TLOC) due to global cerebral hypoperfusion, with rapid onset, short duration, and spontaneous complete recovery. NOT seizure, NOT hypoglycemia, NOT stroke.
Not all TLOC is syncope. Differential: seizure (postictal state, tongue biting, incontinence), hypoglycemia (glucose < 50), TIA (focal deficits), psychogenic pseudosyncope (eyes closed, prolonged duration).
📋 On Rounds
Pimp Questions
Q: What are the high-risk ECG findings in syncope?
A: Bifascicular block, QTc > 500ms, Brugada pattern (coved ST in V1-V3), pre-excitation (WPW), Mobitz II or complete heart block, sustained or non-sustained VT, sinus pauses > 3 sec, new Q waves suggesting MI. Any of these = admit for monitoring.
Q: What is the San Francisco Syncope Rule (CHESS)?
A: C-HF history, H-Hct < 30%, E-ECG abnormal, S-Shortness of breath, S-Systolic BP < 90. Any positive = high risk (~98% sensitivity). Identifies patients needing admission. Negative SFSR = low risk for 7-day serious outcome.
Q: How do you differentiate syncope from seizure?
A: Syncope: prodrome (lightheaded, warm, diaphoretic), brief LOC (< 30 sec), rapid recovery. Seizure: aura, tonic-clonic activity > 60 sec, tongue biting (lateral), postictal confusion 15-30 min, incontinence. Brief myoclonic jerks CAN occur in syncope (convulsive syncope) -don't be fooled.
Q: When do you admit a patient with syncope?
A: Admit if: abnormal ECG, structural heart disease, exertional syncope, syncope causing significant injury, recurrent syncope, family hx of sudden cardiac death, new neurologic deficits. Low-risk features (young, prodrome, positional trigger, normal ECG, no heart disease) = safe discharge.
Q: What is carotid sinus hypersensitivity?
A: Exaggerated response to carotid sinus stimulation → > 3 sec asystole (cardioinhibitory) or SBP drop > 50 mmHg (vasodepressor) or both (mixed). Common in elderly males. Diagnosed by carotid sinus massage (CSM). Treatment: pacemaker for cardioinhibitory type.
Q: What is the PERC rule's role in syncope?
A: Syncope can be the presenting symptom of PE (up to 17% of PE patients). If you suspect PE, use PERC to rule out (if all 8 criteria negative → no D-dimer needed). If PERC fails → D-dimer or CTPA. Always consider PE in unexplained syncope with tachycardia or hypoxia.
Clinical Examples
Case 1: Vasovagal Syncope
22F fainted while standing in line at DMV. Felt warm, lightheaded, and nauseated beforehand. Witnessed to go limp, regained consciousness in < 30 sec. Normal exam, normal ECG. Dx: Classic vasovagal -prodrome + positional trigger + young + normal ECG. Reassurance and hydration. No workup needed.
Case 2: Cardiac Syncope -Complete Heart Block
78M with h/o CAD found on floor by wife. No prodrome. ECG shows complete heart block with ventricular rate 32. SBP 80. Dx: Cardiac syncope from CHB. Transcutaneous pacing → cardiology for permanent pacemaker. Admit to CCU. No prodrome + abnormal ECG + age = high risk.
Case 3: Orthostatic Syncope
65M on lisinopril, amlodipine, and tamsulosin. Passed out getting up from bed at night. Orthostatics: supine BP 140/80, standing BP 100/60 (drop 40). Dx: Orthostatic hypotension -medication-related (alpha-blocker + antihypertensives). Reduce tamsulosin, hold amlodipine, encourage hydration and compression stockings.
Case 4: Exertional Syncope -HOCM
19M college athlete collapsed during basketball. No prodrome. Exam: harsh crescendo-decrescendo systolic murmur at LLSB that increases with Valsalva. ECG: LVH with deep septal Q waves. Dx: HOCM. Echo confirmed. Restrict from competitive sports. Family screening. Consider ICD if high-risk features. Exertional syncope in young = cardiac until proven otherwise.
Sample Presentation
Mr. Davis is a 74-year-old man with CAD, HTN, and HFrEF (EF 30%) who presents after a witnessed syncopal episode while sitting in a chair. No prodrome. Wife reports he went pale, slumped over, was unresponsive for ~10 seconds, then woke up confused. No seizure activity, no incontinence. ECG shows sinus rhythm with bifascicular block (RBBB + LAFB), QTc 480ms. Orthostatics negative. Troponin negative. BNP elevated at 850.
Key Points: High-risk syncope -no prodrome, structural heart disease (HFrEF), abnormal ECG (bifascicular block). Admit for continuous telemetry monitoring. Consider EP study. Bifascicular block in setting of syncope suggests intermittent complete heart block -may need pacemaker or ICD given EF 30%.
Daily Rounds Checklist
Telemetry review: Any pauses > 3 sec? Any VT runs? Any new arrhythmias?
Orthostatic vitals: Repeat if initially positive or if meds adjusted
ECG changes: Repeat ECG if initial was abnormal or if symptoms recur
12-lead ECG -MANDATORY in every syncope patient. Look for: long QT, Brugada, WPW, heart block, old MI (Q waves), LVH
Orthostatic vitals: SBP drop > 20 mmHg OR DBP drop > 10 mmHg within 3 min of standing = positive
The history + ECG alone will identify the cause in ~50% of syncope patients. Routine labs, CT head, EEG, and carotid ultrasound have extremely low yield and should NOT be ordered unless specifically indicated.
High-Risk ECG Findings
Finding
Suggests
Action
Bifascicular block (RBBB + LAFB or LPFB)
Intermittent complete heart block
Admit, EP consult, likely pacemaker
QTc > 500 ms
Long QT syndrome → torsades de pointes
Admit, telemetry, avoid QT-prolonging drugs
Brugada pattern (coved ST V1-V3)
Brugada syndrome → VF
EP consult, ICD evaluation
Pre-excitation (short PR, delta wave)
WPW → AF with rapid conduction → VF
EP consult for ablation
Mobitz II / CHB
High-grade AV block
Pacing (transcutaneous → permanent)
VT / Non-sustained VT
Ventricular arrhythmia
Admit, EP consult, ICD evaluation
Pathologic Q waves
Prior MI → scar-mediated VT
Echo, EP consult
Selective Testing
Echocardiogram: If cardiac murmur, abnormal ECG, exertional syncope, or known heart disease
Continuous monitoring: Holter (24-48h) if daily symptoms; event monitor (2-4 weeks) if weekly; implantable loop recorder (ILR) for recurrent unexplained syncope ISSUE-3, 2012
EP study: Suspected arrhythmic syncope with non-diagnostic non-invasive workup, structural heart disease
Labs: Only if clinically indicated -CBC (anemia/bleeding), BMP (dehydration), troponin (ACS), BNP (HF), glucose, pregnancy test
Risk Stratification Scores
Score
Criteria
Use
San Francisco Syncope Rule (CHESS)
CHF hx, Hct < 30, ECG abnormal, SOB, SBP < 90
Any positive = high risk. ~98% sensitivity for 7-day serious outcome STePS, 2006
Canadian Syncope Risk Score
Predisposition to vasovagal, heart disease, elevated troponin, abnormal QRS axis, QTc > 480, ED diagnosis, SBP < 90
Validated prediction of 30-day serious adverse events. Score -3 to +11. CSRS, 2016
ROSE Rule
BNP ≥ 300, bradycardia ≤ 50, rectal exam with fecal occult blood, anemia, chest pain, ECG Q-wave, saturation ≤ 94% on RA
Predicts 1-month serious outcome. Any positive = high risk. ROSE, 2010
Canadian Syncope Risk Score -30-day serious adverse event risk after ED syncope (guides admission vs discharge)
Validated score for ED risk stratification. Predicts 30-day serious adverse events. Canadian Syncope Risk Score, Thiruganasambandamoorthy 2016
Predictor
Points
ED diagnosis: vasovagal
−2
Heart disease history (HF, CAD, VHD)
+1
Any ED SBP < 90 or > 180
+2
Troponin elevated (> 99th percentile)
+2
Abnormal QRS axis (< −30° or > 100°)
+1
QRS > 130 ms
+1
Corrected QT > 480 ms
+2
ED diagnosis: cardiac syncope
+2
Score ≤ −1: very low risk (~1%) → safe for discharge. Score ≥ 3: high risk (~20%+) → admit. San Francisco Syncope Rule, Quinn 2004
🚨 Management
Admission Criteria
Admit if ANY of these present: Abnormal ECG, structural heart disease (EF < 35%, severe AS, HOCM), exertional syncope, syncope while supine, family hx of sudden cardiac death < 50, significant injury from syncope, recurrent syncope, new neurologic deficits, suspected PE/ACS.
Cardiac Syncope -Arrhythmic
Bradycardia (sinus node dysfunction, heart block): Permanent pacemaker. Atropine or transcutaneous pacing as bridge.
VT with structural heart disease: ICD implantation. Antiarrhythmics (amiodarone, sotalol) as adjunct. EP study for VT ablation.
Long QT: Avoid QT-prolonging drugs (www.crediblemeds.org). Beta-blockers (nadolol) first-line. ICD if cardiac arrest survivor or recurrent syncope on beta-blockers.
Brugada: ICD for cardiac arrest survivors or spontaneous type 1 with syncope. Avoid fever (triggers arrhythmia). Isoproterenol for VT storm.
WPW: Catheter ablation of accessory pathway (curative in > 95%). Avoid AV nodal blockers (digoxin, verapamil, beta-blockers) in AF with WPW.
Cardiac Syncope -Structural
Severe AS with syncope: Urgent AVR (surgical or TAVR). No medical temporizing.
HOCM: Avoid dehydration, Valsalva, heavy exertion. Beta-blockers or verapamil. ICD if high-risk (family hx SCD, massive LVH > 30mm, unexplained syncope, NSVT). Myectomy or alcohol septal ablation for refractory symptoms.
PE: Anticoagulation. Thrombolytics if Category E PE with hemodynamic compromise.
Tilt training: Progressive standing exercises. Evidence is mixed.
Pacemaker: Only for recurrent vasovagal with documented prolonged asystole (> 3 sec) on ILR. Dual-chamber pacing with rate-drop response. ISSUE-3, 2012
Pharmacologic:Midodrine 5-10mg TID or droxidopa (Northera) for neurogenic OH
Safe for discharge: Young patient (< 50), clear vasovagal trigger, no cardiac history, normal ECG, normal exam, no exertional component, no family hx of SCD. Counsel on prodrome recognition, hydration, and counterpressure maneuvers.
💊 Medications
Medications for Recurrent Syncope
Drug
Indication
Dose
Notes
Midodrine
Orthostatic hypotension
2.5-10 mg PO TID
Alpha-1 agonist. Give morning/noon/afternoon. Avoid evening dose (supine HTN)
Fludrocortisone
Orthostatic hypotension
0.1-0.2 mg PO daily
Volume expansion. Monitor K+ and edema. Avoid in HF
Droxidopa
Neurogenic orthostatic hypotension
100-600 mg PO TID
For autonomic failure (Parkinson's, MSA). Norepinephrine prodrug
Beta-blockers
Long QT syndrome
Nadolol 40-80 mg daily preferred
Reduces risk of cardiac events in LQTS. Non-selective preferred
SSRI (paroxetine)
Refractory vasovagal
20 mg PO daily
Limited evidence. Consider in severely recurrent vasovagal only
Most syncope does not need medications. Vasovagal is treated with counter-pressure maneuvers, hydration, and trigger avoidance. Medication review (stopping offending agents) is often the most important intervention.
⚡ Summary
Summary
The Question That Matters
Transient loss of consciousness from cerebral hypoperfusion, with spontaneous complete recovery.Most syncope is vasovagal and benign; cardiac syncope kills. The entire evaluation is aimed at separating the two, not at finding a cause for every episode.
The History Does Most of the Work
Prodrome of nausea, warmth, tunnel vision, and a trigger such as pain, standing, heat or micturition points to vasovagal.Syncope during exertion, while supine, or with palpitations and no prodrome points to cardiac, as does a family history of sudden death. Injury from the fall favors cardiac, because there was no warning to break it.
ECG on Everyone
Look for the conditions that cause sudden death: long or short QT, Brugada pattern, pre-excitation, ARVC changes, hypertrophic cardiomyopathy, bifascicular block, complete heart block, ischemia. A normal ECG with a normal exam and a typical prodrome is highly reassuring, and a resting ECG is one of the few tests that reliably changes disposition.
Check Orthostatics and Examine the Heart
A fall of 20 mmHg systolic or 10 mmHg diastolic within 3 min of standing.Review medications, which are the commonest reversible cause in older patients: antihypertensives, alpha blockers, diuretics, nitrates, antidepressants. Listen for aortic stenosis and hypertrophic cardiomyopathy, both of which present as exertional syncope.
Order Tests Selectively
Routine head CT, carotid ultrasound and EEG have almost no yield in undifferentiated syncope and should not be reflexive. Echo when structural disease is suspected, ambulatory or implantable monitoring when arrhythmia is suspected but not captured, and exercise testing for exertional syncope. Focal neurology means it was not simple syncope, so image that patient.
Use a Score to Support, Not Replace, Judgment
Canadian Syncope Risk Score and San Francisco Syncope Rule stratify 30-day serious outcomes and help defend a discharge decision. They do not override a worrying history: exertional syncope with a normal workup still warrants investigation.
Admit for the Right Reasons
Abnormal ECG, known structural heart disease or heart failure, exertional or supine syncope, palpitations preceding the event, family history of sudden death, significant injury, persistent abnormal vital signs, or severe anemia and suspected GI bleeding.Age alone is not an admission criterion, though it raises the probability of every dangerous cause.
Distinguish the Mimics and Treat What You Find
Seizure: prolonged postictal confusion, tongue biting laterally, incontinence (brief myoclonic jerks are common in ordinary syncope and are not seizures). Hypoglycemia, intoxication, psychogenic pseudosyncope.Treat vasovagal disease with education, trigger avoidance, fluid and salt, and counterpressure maneuvers, with midodrine or fludrocortisone for refractory cases. Cardiac syncope is treated by treating the cardiac disease, and it needs driving restrictions discussed and documented.
History (position, prodrome, exertional, family hx SCD) + orthostatic vitals + 12-lead ECG. That's it for low-risk. Echo if murmur/abnormal ECG/exertional. Labs only if indicated. Skip CT head and EEG.
Conduction system disease from AV node to His-Purkinje. Know which blocks are benign (Mobitz I) vs which need pacing (Mobitz II, 3rd degree). Atropine is your bridge while you call for the pacer.
🔍 Overview
AV Block Classification
Type
ECG Pattern
Level of Block
Clinical Significance
Needs Pacing?
1st Degree
PR > 200 ms, every P followed by QRS
AV node delay
Benign. No treatment needed. Common in athletes, vagal tone, beta-blockers.
Usually benign. Common in inferior MI (RCA supplies AV node), athletes, digoxin. Often transient.
Rarely. Only if symptomatic (bradycardia with hemodynamic compromise).
2nd Degree -Mobitz II
Constant PR interval → sudden dropped QRS. No progressive prolongation.
Below His bundle (infranodal)
DANGEROUS. High risk of progressing to complete heart block without warning. Often associated with anterior MI, structural disease.
Yes -pacemaker indicated even if asymptomatic.
3rd Degree (Complete)
Complete AV dissociation. P waves march through at their own rate. QRS at escape rate (junctional 40–60 or ventricular 20–40).
Complete block at any level
EMERGENCY if symptomatic. May be stable if junctional escape with narrow QRS. Wide QRS escape = unstable, unreliable.
Yes -permanent pacemaker.
Mobitz I = safe (AV node, usually transient). Mobitz II = dangerous (infranodal, can drop to complete block suddenly). The key distinction: does the PR progressively lengthen before the drop? Yes = Mobitz I. No = Mobitz II.
Common Causes
Medications -beta-blockers, CCBs (verapamil/diltiazem), digoxin, amiodarone (most common reversible cause)
Ischemia -inferior MI (AV node block, often transient), anterior MI (His-Purkinje, often permanent)
Degenerative -fibrosis of conduction system (Lenegre disease, Lev disease) -most common in elderly
Infiltrative -sarcoidosis (think cardiac sarcoid in young patient with unexplained heart block), amyloidosis
Infectious -Lyme disease (early disseminated → AV block, usually reversible with antibiotics), endocarditis with abscess
Post-surgical -TAVR, septal myectomy, congenital heart surgery
🚨 Management
Acute Symptomatic Bradycardia
Step 1
Atropine 0.5 mg IV q3–5 min (max 3 mg). Works for AV nodal block (1st degree, Mobitz I, junctional). Does NOT work for infranodal block (Mobitz II, 3rd degree with wide escape) -the block is below where atropine acts.
🔄 Updated Practice: Old teaching: atropine works for all types of heart block. Current practice: atropine only works for NODAL blocks (1st degree AV block, Mobitz Type I/Wenckebach) by increasing AV node conduction via vagolytic effect. It does NOT work for INFRANODAL blocks (Mobitz Type II, complete/3rd degree heart block), and can paradoxically worsen the block by increasing atrial rate without improving ventricular conduction. Infranodal blocks require transcutaneous or transvenous pacing.
Step 2
If atropine fails: transcutaneous pacing (external pads). Set rate 60–80, increase mA until capture. Sedate the patient -it's painful. This is a bridge.
Step 3
Transvenous pacing (temporary pacing wire via IJ/subclavian/femoral). Definitive temporary bridge until permanent pacer.
Bridge agents
While awaiting pacing: dopamine 5–20 mcg/kg/min or epinephrine 2–10 mcg/min or isoproterenol 2–20 mcg/min (β₁ chronotropy).
Permanent Pacemaker Indications
3rd degree AV block (symptomatic or asymptomatic) ACC/AHA/HRS Bradycardia Guidelines, Kusumoto 2019
Mobitz II (symptomatic or asymptomatic -high progression risk)
Always rule out reversible causes before permanent pacing: medication effect (hold offending drugs and reassess), Lyme disease (treat with IV ceftriaxone), inferior MI (AV block often resolves in 5–7 days), hyperkalemia, hypothyroidism. ACC/AHA/HRS, 2019
🧪 Workup
Workup
ECG -degree and level of block
BMP + Mg²⁺ -hyperkalemia
Medication review -BB, CCB, digoxin, amiodarone
TSH -hypothyroidism
Lyme serology -AV block in Lyme carditis
Troponin -inferior MI → AV node ischemia
Echo -structural/infiltrative disease
📋 On Rounds
Why doesn't atropine work in Mobitz II or infranodal block?
Atropine is a parasympatholytic (anticholinergic) -it blocks vagal tone at the AV node, increasing conduction through the node. In Mobitz II and 3rd degree heart block with wide QRS, the block is below the AV node (in the His bundle or bundle branches) where there is no parasympathetic innervation. Atropine has no target to act on.
A 28-year-old presents with new-onset 3rd degree heart block. What diagnosis should you consider?
Lyme disease (Lyme carditis) and cardiac sarcoidosis. Lyme is the most important to catch -it's fully reversible with IV ceftriaxone (2g daily × 14–21 days). Occurs in early disseminated Lyme (weeks–months after tick bite). Get Lyme serologies in any young patient with unexplained heart block, especially in endemic areas.
What medications cause heart block, and which are reversible?
Reversible (hold and observe): beta-blockers (metoprolol, atenolol, carvedilol), non-DHP calcium channel blockers (diltiazem, verapamil), digoxin, amiodarone, clonidine. Metabolic causes (correct the cause): hyperkalemia (most dangerous -can cause any degree of block → sine wave → arrest), hypothyroidism, hypothermia.
An inferior STEMI patient develops complete heart block. Is this the same as chronic CHB?
No -and the management is different. Inferior MI causes AV node ischemia (supplied by RCA in 85%) → typically a junctional escape rhythm at 40-60 bpm (narrow QRS, relatively stable). This is usually transient (resolves in 2-7 days) as the AV node recovers. Management: temporary pacing if hemodynamically compromised, atropine may help (vagal-mediated). Does NOT routinely need a permanent pacer -monitor and reassess.
Case 1: Symptomatic Mobitz Type II
Presentation: 70M with recurrent syncope over 2 weeks, baseline HTN and prior anterior MI. Arrives after witnessed syncopal episode. HR 38, BP 88/54. ECG shows 2:1 AV block with wide QRS (RBBB morphology) and constant PR intervals on conducted beats, consistent with Mobitz Type II.
Management: Transcutaneous pacing pads placed immediately. Atropine 0.5 mg IV given, no response (expected: infranodal block has no vagal innervation to antagonize). Capture achieved with transcutaneous pacing at 70 mA. Dopamine drip started at 5 mcg/kg/min for BP support. EP consulted, permanent dual-chamber pacemaker (DDD) placed next day.
Teaching Point: Mobitz II with wide QRS = infranodal block. Atropine will not work. Do not delay pacing. Even asymptomatic Mobitz II is a Class I indication for permanent pacemaker.
Case 2: Complete Heart Block Post-Inferior STEMI
Presentation: 58F with acute inferior STEMI (RCA occlusion) taken for PCI. Post-cath, develops new 3rd degree AV block with narrow QRS junctional escape rhythm at 42 bpm. BP 96/60, mildly symptomatic with lightheadedness but alert.
Management:Atropine 0.5 mg IV, HR improves transiently to 56 bpm (AV nodal block, so atropine has partial effect). Temporary transvenous pacing wire placed via RIJ as backup. Monitored on telemetry. By day 3, AV conduction returns, 1st degree AV block only. Pacing wire removed day 4.
Teaching Point: Inferior MI causes AV node ischemia (RCA supplies AV node in 85%). Heart block is usually transient (resolves in 2–7 days) with a stable junctional escape. Does NOT routinely require permanent pacing, monitor and reassess. Contrast with anterior MI, where heart block is infranodal and often permanent.
Case 3: Drug-Induced Bradycardia & High-Grade AV Block
Presentation: 82M with HFrEF and atrial fibrillation, on Metoprolol Succinate (Toprol-XL) 100 mg daily + Diltiazem (Cardizem) 120 mg TID + Digoxin (Lanoxin) 0.125 mg daily. Admitted with fatigue and near-syncope. HR 32, BP 84/50. ECG shows 1st degree AV block progressing to high-grade AV block (3:1 and 4:1 conduction) with narrow QRS.
Management: All three AV-nodal blocking agents held immediately. Atropine 1 mg IV, transient improvement to HR 48. Glucagon 3 mg IV bolus then 3 mg/hr drip (beta-blocker reversal). Digoxin level drawn, 2.4 ng/mL (elevated). Transcutaneous pads placed prophylactically. Over 36 hours, metoprolol and diltiazem cleared, HR improved to 64, normal sinus rhythm with 1st degree AV block only.
Teaching Point: Triple AV-nodal blockade (beta-blocker + non-DHP CCB + digoxin) is a common iatrogenic cause of high-grade AV block. First step: hold all offending agents and check digoxin level. Glucagon is the specific antidote for beta-blocker toxicity. Most drug-induced heart block resolves after drug washout, avoid permanent pacing until reversible causes are excluded.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 76-year-old on metoprolol 200 mg daily presenting with dizziness and HR 34. ECG shows complete (third-degree) AV block with a ventricular escape rate of 34 bpm."
Key Points to Cover on Rounds
Third-degree AV block. Hemodynamically stable but symptomatic. Metoprolol held (reversible cause). Temporary transcutaneous pacing pads placed. Atropine 0.5 mg given with transient improvement to HR 48. Lyme screen and TSH sent. Troponin negative. EP consulted for permanent pacemaker. Plan: if no improvement after holding BB ×24h, transvenous pacing wire → permanent pacer.
💊 Medications
Key Medications -Heart Block & Bradycardia
Drug
Dose
Route
Notes
Atropine 1ST LINE
0.5-1 mg IV, repeat q3-5 min (max 3 mg)
IV push
Vagolytic -works for nodal block only (1st degree, Mobitz I). Will NOT work for Mobitz II or 3rd degree (infranodal) -no vagal innervation below AV node. Can paradoxically worsen infranodal block.
Isoproterenol (Isuprel)
2-10 mcg/min IV drip
IV
Beta-1 + Beta-2 agonist. Increases HR and AV conduction. Bridge to pacing. Caution: increases myocardial O₂ demand.
Dopamine
5-20 mcg/kg/min IV drip
IV
Chronotropic at 5-10 mcg/kg/min (beta effect). Alternative to isoproterenol if hypotensive. Higher doses add alpha vasoconstriction.
Epinephrine
2-10 mcg/min IV drip
IV
For symptomatic bradycardia unresponsive to atropine. Potent chronotrope and vasopressor.
Transcutaneous pacing
Start 60-80 mA, rate 60-80 bpm
External pads
Bridge to transvenous pacing. Painful -requires sedation. Verify mechanical capture (palpable pulse with each complex).
Transvenous pacing
Per EP/cardiology
Central venous
Temporary pacing wire via RIJ or femoral vein. For refractory symptomatic bradycardia awaiting permanent pacemaker.
First step: Review medication list -hold all AV-nodal blockers (beta-blockers, non-DHP CCBs, digoxin, amiodarone). Check K⁺ and Mg²⁺. Many cases of heart block are iatrogenic and reversible.
⚡ Summary
Summary
Mobitz I Is Safe, Mobitz II Is Not
Mobitz I (Wenckebach) is at the AV node, usually transient and often benign.Mobitz II is infranodal and can drop to complete block without warning, so it needs pacing. The discriminator is whether the PR interval progressively lengthens before the dropped beat: yes is Mobitz I, no is Mobitz II.
Atropine Only Works Above the Node
It is vagolytic, so it speeds conduction through the AV node.It works in first-degree block and Mobitz I. It does not work in Mobitz II or complete heart block, which are infranodal, and it can make them worse by increasing atrial rate without improving conduction. Move to pacing rather than repeating the dose.
Escalate in the Right Order for Unstable Bradycardia
Atropine 1 mg IV, repeatable to 3 mg, then transcutaneous pacing, then a chronotropic infusion (dopamine or epinephrine), then transvenous pacing.Sedate for transcutaneous pacing, which is painful, and confirm mechanical capture with a pulse, not just the pacing spikes on the monitor.
Look at the Medication List First
Many cases are iatrogenic and fully reversible.Hold every AV nodal blocking agent: beta blockers, non-dihydropyridine calcium channel blockers, digoxin, amiodarone, and also clonidine and cholinesterase inhibitors. Check potassium and magnesium. Reassess after the drug clears before committing to a device.
Exclude the Reversible Causes Before Pacing
Medication effect, hyperkalemia, hypothyroidism, and Lyme carditis, which is treated with IV ceftriaxone and typically resolves. Inferior MI causes AV block that usually resolves in 5 to 7 days, because it is nodal and vagally mediated, so it rarely needs a permanent device. Anterior MI with new block is different: it means extensive septal infarction, it is infranodal, and it does need permanent pacing.
Complete Heart Block Is Recognized by Dissociation
Regular P waves and regular QRS complexes marching independently, with a QRS rate slower than the P rate.The escape rhythm predicts the risk: a narrow junctional escape at 40 to 60 is relatively stable, while a wide ventricular escape at 20 to 40 is unreliable and can fail without warning.
Know the Pacing Indications
Symptomatic bradycardia of any type, Mobitz II, complete heart block, and advanced second-degree block, once reversible causes are excluded.Also alternating bundle branch block and symptomatic sinus node dysfunction.Asymptomatic Mobitz I and first-degree block do not need pacing, and treating a number rather than a patient is the commonest over-treatment here.
Consider the Other Diagnoses a Slow Heart Rate Signals
BRASH syndrome: bradycardia, renal failure, AV nodal blockade, shock and hyperkalemia, a self-reinforcing spiral in which each element worsens the others, and it needs all of them treated at once rather than the bradycardia alone. Also look for infiltrative disease, cardiac sarcoidosis and amyloidosis, in unexplained conduction disease in a younger patient, since finding it changes the treatment entirely.
Inflammation of the myocardium. Classic presentation: young patient with recent viral illness → chest pain + troponin elevation + new HF. Ranges from mild (self-limited) to fulminant (cardiogenic shock). Cardiac MRI is the key diagnostic tool.
🔍 Overview
Presentation Spectrum
Type
Presentation
Hemodynamics
Prognosis
Acute (non-fulminant)
Chest pain, dyspnea, palpitations. Preceded by viral URI 1–4 weeks prior. Mild-moderate LV dysfunction.
Giant cell myocarditis -idiopathic, associated with autoimmune diseases (IBD, thymoma)
Checkpoint inhibitor myocarditis: rare (~1%) but mortality > 40%. Presents 1–3 months after starting therapy. Stop the drug immediately. High-dose IV methylprednisolone. Cardiology + oncology co-management.
Diagnosis
Test
Findings
Troponin
Elevated (may mimic MI). Often with recent viral prodrome.
ECG
Diffuse ST changes (may mimic pericarditis or STEMI), sinus tachycardia, arrhythmias (VT, heart block), low voltage.
Echo
New wall motion abnormalities (often non-territorial -unlike MI). Reduced EF. May see pericardial effusion.
Cardiac MRI KEY DIAGNOSTIC TOOL
Lake Louise criteria: (1) T2 hyperintensity (edema), (2) late gadolinium enhancement -mid-wall or epicardial pattern (unlike MI which is subendocardial/transmural). (3) T1 mapping abnormalities. Sensitivity ~80%, specificity ~90%.
Endomyocardial biopsy
Gold standard but rarely done (low sensitivity due to sampling error). Indicated in: fulminant myocarditis, suspected giant cell, no improvement despite treatment, need to guide immunosuppression.
🚨 Management
Treatment
Supportive care -standard HF therapy if reduced EF (ACEi/ARB, beta-blocker, diuretics as needed). Avoid NSAIDs in acute phase (may impair healing).
Activity restriction -no competitive sports for 3–6 months minimum. Risk of fatal arrhythmias with exertion. Repeat echo and MRI before return to play.
Arrhythmia management -telemetry monitoring. Life vest (wearable defibrillator) if EF < 35% acutely. Avoid permanent ICD in acute phase -EF may recover. Reassess at 3–6 months.
Fulminant → ICU. Inotropes, vasopressors. Early MCS (Impella/ECMO) if deteriorating -these patients often recover if supported through the acute phase.
Giant cell myocarditis → immunosuppression (cyclosporine + steroids ± azathioprine). Early transplant evaluation. Giant Cell Myocarditis Registry, 1997: immunosuppression improved survival from 3 months to 12 months.
Checkpoint inhibitor myocarditis → stop drug + high-dose IV methylprednisolone 1g/day × 3–5 days, then oral taper.
Monitoring, Myocarditis
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
Endomyocardial biopsy -only if giant cell suspected
💊 Medications
Medications
Drug
Dose
Route
Notes
Lisinopril (Zestril)
2.5-20 mg daily
PO
ACEi for LV remodeling. Start low, uptitrate. ARB if ACEi-intolerant.
Carvedilol (Coreg)
3.125-25 mg BID
PO
Low-dose BB -titrate cautiously. Hold if cardiogenic shock or decompensated HF.
Furosemide (Lasix)
20-80 mg PRN
IV/PO
Diuresis for fluid overload/congestion. Titrate to euvolemia.
Avoid NSAIDs
-
-
Worsen myocardial inflammation and necrosis. Contraindicated even though chest pain is prominent.
Immunosuppression
Per biopsy/pathology
IV/PO
ONLY for giant cell myocarditis (cyclosporine + steroids) or eosinophilic myocarditis (high-dose steroids). NOT for viral myocarditis.
IVIG
2 g/kg over 2-5 days
IV
Consider in select cases (pediatric, fulminant). Evidence mixed. Not routine.
Inotropes / MCS
Per hemodynamics
IV
Milrinone or dobutamine for cardiogenic shock. Impella/ECMO for fulminant myocarditis with refractory shock.
📋 On Rounds
How does cardiac MRI distinguish myocarditis from MI?
Late gadolinium enhancement (LGE) pattern. In MI, LGE follows a coronary distribution and is subendocardial or transmural (starts from the endocardium and extends outward). In myocarditis, LGE is typically mid-wall or epicardial (spares the subendocardium) and is non-territorial (doesn't match a coronary artery distribution).
Why does fulminant myocarditis have a paradoxically better long-term prognosis?
Fulminant myocarditis represents an overwhelming but robust immune response -the immune system aggressively attacks the virus (and unfortunately, the myocardium). If the patient survives the acute phase (with MCS if needed), the strong immune response effectively clears the virus, and the myocardium recovers -~90% regain normal LV function.
Why do you avoid NSAIDs in acute myocarditis even though they're first-line for pericarditis?
In pericarditis, inflammation is limited to the pericardium -NSAIDs reduce inflammation and improve symptoms. In myocarditis, the inflammation involves the myocardium itself. Animal studies showed NSAIDs increased myocardial necrosis and mortality in viral myocarditis by impairing the immune response needed to clear the virus and by increasing viral replication. NSAIDs also reduce renal blood flow which is detrimental in patients with reduced EF.
A 28-year-old recovered from myocarditis with EF 35%. When can they return to exercise?
No competitive sports or intense exercise for minimum 3-6 months after acute myocarditis regardless of EF recovery. This is because active myocardial inflammation creates a substrate for fatal ventricular arrhythmias during exercise (catecholamine surge + inflamed myocardium = VT/VF). Before returning: (1) ≥ 3 months from onset, (2) EF normalized on repeat echo, (3) No LGE on cardiac MRI (or stable/reduced)
Clinical Examples
📋 Case 1, Viral Myocarditis with Acute HF
Patient: 26M with chest pain and dyspnea 10 days after a flu-like illness. Troponin 6.8, BNP 2400. ECG: diffuse ST elevation without reciprocal changes. Echo: EF 30%, global hypokinesis. No coronary disease on angiography.
Key findings: Acute viral myocarditis with new-onset HFrEF. Clean coronaries exclude ACS. Diffuse ST changes (not territorial) + recent viral prodrome + young patient = classic presentation.
Management:
Cardiac MRI, Lake Louise criteria: T2 edema + LGE in non-coronary distribution (mid-wall/epicardial) confirms myocarditis
GDMT for HFrEF: ACEi/ARB, beta-blocker (once stable), MRA if EF ≤ 35%
Telemetry monitoring, arrhythmia risk highest in acute phase (VT/VF)
NO NSAIDs (worsen inflammation and remodeling in myocarditis)
Repeat echo at 3-6 months, most viral myocarditis recovers EF (60-70% normalize)
Teaching point: Do NOT place an ICD during acute myocarditis even if EF ≤ 35%. Most patients recover EF, wait ≥ 3-6 months and reassess. LifeVest (wearable defibrillator) is a bridge if high arrhythmia risk.
📋 Case 2, Fulminant Myocarditis
Patient: 32F with 2 days of progressive dyspnea, now in cardiogenic shock. HR 120, BP 72/48, cool extremities, lactate 6.2. Echo: EF 10%, global severe hypokinesis. Troponin 42. No prior cardiac history.
Key findings: Fulminant myocarditis, rapid-onset cardiogenic shock in a previously healthy patient. Paradoxically, fulminant myocarditis has BETTER long-term prognosis than acute myocarditis if the patient survives the acute phase (stronger immune response → better viral clearance).
Early mechanical circulatory support: Impella or VA-ECMO if refractory to inotropes
Endomyocardial biopsy, rule out giant cell myocarditis (requires immunosuppression) or eosinophilic myocarditis
Avoid beta-blockers acutely in cardiogenic shock (can worsen hemodynamics)
If giant cell myocarditis on biopsy: high-dose steroids + cyclosporine (without immunosuppression, mortality > 80%)
Teaching point: Fulminant myocarditis is a "bridge to recovery" disease, patients who survive the acute phase often recover near-normal EF. Aggressive mechanical support (ECMO/Impella) saves lives. Biopsy is critical to exclude giant cell myocarditis.
📋 Case 3, Immune Checkpoint Inhibitor Myocarditis
Patient: 58M on pembrolizumab for melanoma × 3 cycles. New fatigue, dyspnea, palpitations. Troponin 2.4 (was normal at baseline). ECG: new conduction delay, PR prolongation. Echo: EF 45% (was 60%).
Key findings: Immune checkpoint inhibitor (ICI) myocarditis, occurs in 1-2% of ICI-treated patients but mortality is 25-50%. Can present with conduction abnormalities, arrhythmias, or HF. Often coexists with myositis and myasthenia gravis.
Management:
Hold pembrolizumab immediately (permanently discontinue, do not rechallenge)
High-dose methylprednisolone 1g IV daily × 3-5 days → prednisone 1 mg/kg with slow taper
If steroid-refractory: add mycophenolate, infliximab, or abatacept
Continuous telemetry, high-grade AV block and VT are common and often fatal
Check CK (concurrent myositis), anti-AChR antibodies (concurrent MG), and cardiac MRI
Teaching point: ICI myocarditis is the most lethal irAE, early troponin monitoring and a low threshold for holding therapy saves lives. Conduction abnormalities (PR prolongation, BBB) may be the first sign before EF drops.
📣 Sample Presentation
One-Liner
"Mr. Reyes is a 28-year-old presenting with chest pain and dyspnea 10 days after a viral illness. Troponin 8.2, BNP 1,400. ECG shows diffuse ST changes. Echo EF 35% with global hypokinesis. Cardiac MRI shows late gadolinium enhancement consistent with myocarditis."
Asymmetric septal hypertrophy (≥ 15 mm) not explained by loading conditions. Autosomal dominant. The #1 cause of sudden cardiac death in young athletes. Know the LVOT obstruction physiology -it drives everything.
🔍 Overview
LVOT Obstruction -The Core Physiology
~70% of HCM patients have dynamic LVOT obstruction (gradient ≥ 30 mmHg at rest or with provocation). The thickened septum narrows the outflow tract → high-velocity flow → Venturi effect pulls the anterior mitral leaflet toward the septum (SAM = systolic anterior motion) → further obstruction + mitral regurgitation.
Avoid in HCM: nitrates, diuretics, digoxin, ACEi/ARBs (drop preload/afterload → worsen obstruction), dobutamine/milrinone (increase contractility → worsen obstruction). If hypotensive → IV fluids + phenylephrine. NOT vasopressors that increase contractility.
Clinical Features
Murmur: harsh crescendo-decrescendo systolic murmur at LLSB. Louder with Valsalva and standing (decreased preload). Softer with squatting (increased preload). This is the opposite of most murmurs.
EXPLORER-HCM, 2020: reduced LVOT gradient from 74 → 12 mmHg. Improved symptoms and exercise capacity. First targeted therapy for HCM. Requires REMS program (risk of excessive EF reduction).
Invasive Therapy (Refractory Symptoms)
Septal myectomy (Morrow procedure) -surgical resection of hypertrophied septum. Gold standard for refractory obstructive HCM. Success rate > 95%. Mortality < 1% at experienced centers.
Alcohol septal ablation -ethanol injection into septal perforator artery → controlled MI of hypertrophied septum. Alternative for high surgical risk. Higher rates of heart block (10–20%) and need for permanent pacemaker.
Sudden Cardiac Death Risk -ICD Criteria
HCM is the #1 cause of sudden cardiac death in young athletes. Risk stratify ALL HCM patients.
Valsalva decreases venous return (preload) → smaller LV cavity → the hypertrophied septum and anterior mitral leaflet are now closer together → more SAM → greater LVOT obstruction → louder murmur. This is the opposite of AS (fixed obstruction -murmur gets softer with decreased preload because less blood crosses the valve). The dynamic nature of the obstruction is the key concept -anything that makes the ventricle smaller worsens HCM obstruction.
What is mavacamten and why is it a breakthrough?
Mavacamten is a first-in-class cardiac myosin inhibitor -it directly reduces the number of myosin-actin cross-bridges that form during systole, reducing contractility at the sarcomere level. EXPLORER-HCM, 2020 showed it reduced resting LVOT gradient from 74 to 12 mmHg (vs 4 mmHg reduction with placebo). This is the first drug that targets the root cause of HCM (excess contractility) rather than compensating for it with negative chronotropy (BB)
Why are vasodilators, diuretics, and digoxin dangerous in obstructive HCM?
In obstructive HCM, the septum narrows the LVOT and the anterior mitral leaflet is pulled into the outflow tract during systole (SAM = systolic anterior motion). Vasodilators (ACEi, ARBs, nitrates, dihydropyridine CCBs) → reduce afterload → less resistance to outflow → LVOT gradient INCREASES → worsens obstruction. Diuretics → reduce preload → smaller LV cavity → septum and mitral leaflet are closer together → obstruction worsens.
Clinical Examples
📋 Case 1, Symptomatic Obstructive HCM
Patient: 48M with exertional dyspnea and near-syncope when climbing stairs. Systolic murmur that increases with Valsalva. Echo: septal thickness 24 mm, LVOT gradient 72 mmHg at rest, SAM of MV with moderate MR. EF 70%.
Key findings: Obstructive HCM (resting gradient > 30 mmHg) with NYHA II-III symptoms. SAM causes dynamic LVOT obstruction + MR. Gradient worsens with decreased preload (Valsalva, dehydration, standing).
Management:
Metoprolol succinate 50 mg → titrate to 200 mg daily (first-line, slows HR, increases filling time, reduces gradient)
If refractory to all medical therapy: septal myectomy (surgical, gold standard) or alcohol septal ablation
Teaching point: In HCM, everything that reduces preload or increases contractility worsens obstruction. The hemodynamic goal is the opposite of HFrEF, increase preload, decrease contractility, slow HR.
📋 Case 2, Sudden Cardiac Death Risk Stratification
Patient: 22M diagnosed with HCM on screening echo after his brother died suddenly during basketball at age 19. Septal thickness 30 mm, no resting LVOT obstruction, EF 65%. Asymptomatic. Holter: 3-beat run of NSVT.
Key findings: Multiple SCD risk factors: family history of SCD, massive LVH (≥ 30 mm), NSVT on Holter. HCM is the #1 cause of SCD in young athletes.
Management:
ICD implantation recommended, ≥ 1 major risk factor for SCD in HCM warrants primary prevention ICD
SCD risk factors: family hx SCD, syncope, NSVT, max wall thickness ≥ 30 mm, abnormal BP response to exercise
No competitive sports (AHA/ACC Class III recommendation for HCM with any risk factor)
Cardiac MRI with LGE, extent of fibrosis is an emerging risk predictor
Screen all first-degree relatives with echo + ECG (genetic counseling, consider genetic testing)
Teaching point: The decision to place an ICD in HCM requires only ONE major risk factor. This is different from HFrEF (where EF ≤ 35% is the threshold). A 22-year-old with massive LVH + family SCD + NSVT has a very high SCD risk.
📋 Case 3, HCM with Atrial Fibrillation
Patient: 56F with known HCM, presents with palpitations and dyspnea. HR 148 irregularly irregular, BP 88/60. Echo: LVOT gradient now 95 mmHg (was 35 at baseline). New moderate MR.
Key findings: Afib with rapid ventricular response in HCM, hemodynamic emergency. Loss of atrial kick + fast HR → decreased filling time → dramatically increased LVOT gradient → hypotension.
Management:
IV phenylephrine for hypotension (pure alpha agonist, increases afterload without increasing contractility, reduces gradient)
IV metoprolol for rate control (do NOT use diltiazem or verapamil acutely if hypotensive)
If hemodynamically unstable: emergent synchronized cardioversion
Long-term anticoagulation, ALL HCM patients with Afib need anticoagulation regardless of CHA₂DS₂-VASc score
Consider amiodarone or catheter ablation for rhythm control (Afib recurrence is poorly tolerated in HCM)
Teaching point: Afib in HCM is a medical emergency. Unlike the general population, ALL HCM patients with Afib require anticoagulation, the stroke risk is markedly elevated regardless of CHA₂DS₂-VASc score.
📣 Sample Presentation
One-Liner
"Ms. Washington is a 34-year-old referred after a murmur was found on sports physical. Echo shows septal thickness 22 mm, LVOT gradient 65 mmHg at rest, SAM of mitral valve. Asymptomatic."
Key Points to Cover on Rounds
Known HCM with obstruction (resting gradient 65). Currently asymptomatic, NYHA class I. SCD risk assessment: no FH of SCD, no unexplained syncope, no NSVT on Holter, max wall thickness 22 mm (risk factor), no exercise hypotension. ICD discussion: intermediate risk based on wall thickness -shared decision-making. Started metoprolol 25 mg BID. Avoid dehydration, vasodilators, digoxin. Activity: no competitive sports.
💊 Medications
Key Medications -Hypertrophic Cardiomyopathy
The governing principle: anything that shrinks the ventricle or speeds it up makes obstruction worse. In obstructive HCM the gradient rises when preload or afterload falls, or when contractility rises. That single idea explains every drug choice and every drug to avoid below.
Drug
Dose
Role
Watch for
Metoprolol / bisoprolol 1ST LINE
Titrate to symptoms and heart rate
First line for symptomatic obstruction. Slows the heart, so diastole is longer and filling is better, and reduces contractility so the gradient falls.
Bradycardia, fatigue, bronchospasm. Titrate to symptoms, not to a target gradient.
Verapamil
120 to 480 mg daily
Alternative when beta-blockers are not tolerated. Improves diastolic relaxation.
Dangerous in severe obstruction with hypotension or a very high gradient, where its vasodilatory effect can precipitate collapse. Avoid in decompensated patients.
Disopyramide
Titrated, usually with a beta-blocker
Added for refractory obstruction before considering septal reduction.
Potent negative inotrope, which is the point. QT prolongation and marked anticholinergic effects (dry mouth, urinary retention). Pair with an AV nodal blocker as it can accelerate AV conduction in AF.
Mavacamten (Camzyos) CARDIAC MYOSIN INHIBITOR
Start 5 mg daily, titrate among 2.5, 5, 10 and 15 mg by echo
Reduces excessive actin-myosin cross-bridging, lowering the gradient and improving symptoms in obstructive HCM EXPLORER-HCM, 2020.
Dispensed only through a REMS program because it can reduce LVEF and precipitate heart failure. Echo-guided titration is mandatory; hold the drug if LVEF falls below 50%. Numerous CYP interactions.
Anticoagulation
DOAC or warfarin
Any atrial fibrillation in HCM warrants anticoagulation, irrespective of the CHA2DS2-VASc score.
HCM confers a stroke risk that the usual score underestimates, so the score is not used to decide here.
Avoid in obstructive HCM:dihydropyridine calcium blockers (amlodipine, nifedipine) and nitrates, which drop afterload and preload; aggressive diuresis, which drops preload; and digoxin or other inotropes, which raise contractility. Each one widens the gradient. Treat hypotension in obstructive HCM with fluids and phenylephrine, never with an inotrope.
⚡ Summary
Summary
One Principle Explains Everything
Anything that shrinks the ventricle or speeds it up makes the obstruction worse. The gradient rises when preload falls, when afterload falls, or when contractility rises. Every drug rule, every murmur maneuver and every hemodynamic instruction on this page follows from that one sentence.
Define It
Asymmetric septal hypertrophy of 15 mm or more, not explained by loading conditions. Autosomal dominant, from sarcomere protein mutations. It is the leading cause of sudden cardiac death in young athletes, and it can be entirely asymptomatic until that event.
The Murmur Behaves Backwards
The systolic murmur increases with Valsalva and on standing (both reduce preload) and decreases with squatting and handgrip (which increase preload and afterload). Aortic stenosis does the opposite, and that is the bedside discriminator between the two.
The Drugs to Avoid
Nitrates, diuretics in excess, dihydropyridine calcium channel blockers, ACE inhibitors and ARBs all drop preload or afterload and worsen the gradient.Digoxin, dobutamine and milrinone raise contractility and worsen it too. These are the standard drugs for other cardiac disease, which is what makes this so easy to get wrong.
Treat Hypotension Backwards From Instinct
Give IV fluid and phenylephrine.Do not give inotropes: a pure alpha agonist raises afterload and relieves the obstruction, whereas an inotrope worsens it and can precipitate arrest. This is the reverse of almost every other shock algorithm.
Medical Therapy Slows and Fills
Beta blockers first line, which slow the heart and allow diastolic filling. Verapamil as an alternative, though with caution in severe obstruction or high filling pressures. Disopyramide for its negative inotropy in refractory symptoms. Mavacamten, a cardiac myosin inhibitor, reduces the gradient and symptoms in obstructive disease (EXPLORER-HCM) and requires echocardiographic monitoring of the ejection fraction.
Invasive Options for Refractory Symptoms
Septal myectomy is the gold standard in experienced centers, with excellent durability. Alcohol septal ablation for poor surgical candidates, at the cost of a heart block risk requiring a pacemaker. These treat symptoms, not sudden death risk, so an ICD decision is made separately.
Risk Stratify Every Patient for Sudden Death
Family history of sudden cardiac death, unexplained syncope, massive hypertrophy of 30 mm or more, non-sustained ventricular tachycardia on monitoring, and an abnormal blood pressure response to exercise. Add extensive late gadolinium enhancement on MRI and apical aneurysm as modifiers. Screen first-degree relatives with ECG and echocardiography, and discuss genetic testing, since the disease is inherited and the index case is often found through a relative.
GDMT optimization with the four pillars, HFrEF vs HFpEF distinction, device therapy, and long-term management. For acute decompensation and ICU management, see ADHF.
🔍 Overview
Classification
Type
EF
Pathology
Key Feature
HFrEF (systolic)
≤ 40%
Impaired contraction
GDMT* proven to reduce mortality. All four pillars apply. *GDMT = Guideline-Directed Medical Therapy
HFmrEF (mid-range)
41–49%
Borderline -may behave like either
Emerging data supports GDMT (especially SGLT2i). Treat like HFrEF if symptomatic.
HFpEF (diastolic)
≥ 50%
Impaired relaxation / filling
No mortality-reducing GDMT until SGLT2i. Manage volume, comorbidities, and now SGLT2i.
NYHA Functional Classification
Class
Symptoms
Implication
I
No limitation. Ordinary activity does not cause symptoms.
Optimize GDMT. Continue current regimen.
II
Slight limitation. Comfortable at rest, symptoms with ordinary activity.
Ensure all four pillars are at target doses.
III
Marked limitation. Comfortable at rest, symptoms with less than ordinary activity.
Unable to carry on any activity without symptoms. Symptoms at rest.
Advanced HF referral. Evaluate for LVAD / transplant.
Key Prognostic Markers
BNP / NT-proBNP -higher levels = worse prognosis. Useful for tracking response to therapy.
Hyponatremia (Na⁺ < 135) -independent predictor of mortality in HF
Peak VO₂ -gold standard for transplant candidacy (≤ 14 mL/kg/min → list)
NYHA class -class III/IV = ↑ mortality
EF -lower EF = higher mortality, but HFpEF also carries significant morbidity
Emerging Therapies
Digitoxin -DIGIT-HF, 2025 showed digitoxin 0.07 mg daily reduced death + HF hospitalization by 18% in advanced HFrEF (NYHA III–IV) on GDMT. Consider as add-on after optimizing all four pillars.
💊 GDMT -The Four Pillars (HFrEF)
▶ How to Escalate GDMT in HFrEF, Step by Step (tap to expand)
Paradigm shift (STRONG-HF, 2022): the old "titrate one drug to max, then add the next" model is dead. Current practice is start all four pillars at low dose within days, then uptitrate over 4-6 weeks. STRONG-HF (Lancet 2022) randomized 1,078 ADHF patients to rapid vs usual uptitration within 2 weeks of discharge: 34% reduction in 180-day death or HF hospitalization. Class I recommendation in the 2022 AHA/ACC/HFSA guideline.
Step 1: Confirm and stabilize before initiating
Check
What
Why
Confirm HFrEF
Echo with EF ≤ 40% (or HFmrEF 41-49%, treat same way per 2022 guideline)
4-pillar GDMT only proven to reduce mortality in HFrEF/HFmrEF. HFpEF gets different management (see HFrEF vs HFpEF section).
Stabilize hemodynamics
SBP ≥ 90, off pressors, no active cardiogenic shock
Starting ARNI or BB in shock will deepen the shock. Stabilize first, then layer GDMT. Loop diuretics for congestion don't wait.
Baseline labs
BMP (K+, Cr, eGFR), NT-proBNP or BNP, iron studies (ferritin, TSAT)
Hyperkalemia or AKI changes which pillars you can safely start. NT-proBNP trends gauge decongestion. Iron deficiency (ferritin < 100, or 100-299 with TSAT < 20%) needs IV iron (AFFIRM-AHF).
Step 2: Start all four pillars at low dose within days
Order in practice: the pillars don't need to be started on the same day, but all four should be on board within 2 weeks of discharge. A common sequencing (when staggered) is SGLT2i + low-dose BB on day 1 (most BP-neutral), then add ARNI day 2-3, then MRA day 3-7 once K+ stable. ARNI requires 36-hour washout from any ACEi (angioedema risk from dual neprilysin/ACE inhibition).
Pillar
Starting Dose
Why Low to Start
1. ARNI (sacubitril/valsartan)
49/51 mg BID if previously on ACEi/ARB and SBP ≥ 100; 24/26 mg BID if naive, elderly, or SBP 95-100
20% MACE reduction vs enalapril (PARADIGM-HF). Start low to limit hypotension and AKI; the BP drop is front-loaded.
Only these three BBs are evidence-based (MERIT-HF, COPERNICUS, CIBIS-II). Atenolol, propranolol, metoprolol tartrate are NOT acceptable substitutes. Negative inotropy at start makes congestion worse if patient is wet, so don't start during active decompensation.
3. MRA
Spironolactone 12.5-25 mg daily, or eplerenone 25 mg daily
30% mortality reduction (RALES, EMPHASIS-HF). Hold if K+ > 5.0 or eGFR < 30. Eplerenone if gynecomastia is a concern (less anti-androgen activity).
4. SGLT2i
Dapagliflozin 10 mg or empagliflozin 10 mg daily (no titration)
25-30% reduction in CV death + HF hospitalization (DAPA-HF, EMPEROR-Reduced), benefit regardless of diabetes status. Expect a 0.2 mg/dL Cr bump (hemodynamic, reverses; do not stop). Initiate down to eGFR 20.
Step 3: Uptitrate over 4-6 weeks to target doses
Drug
Target Dose
How to Titrate
Sacubitril/valsartan
97/103 mg BID
Double the dose q2-4 weeks if SBP and K+ tolerate. Recheck BMP at 1-2 weeks after each step.
Carvedilol
25 mg BID (50 mg BID if > 85 kg)
Double q2 weeks. Hold uptitration if HR < 55 or SBP < 90.
Metoprolol succinate
200 mg daily
Double q2 weeks (12.5 → 25 → 50 → 100 → 200).
Bisoprolol
10 mg daily
Double q2 weeks (1.25 → 2.5 → 5 → 10).
Spironolactone
25-50 mg daily
BMP at 3 days, 1 week, then monthly. Hold if K+ > 5.5.
Repeat echo at 3 months on optimized GDMT before any device decision. 30-40% of new HFrEF will recover EF > 35% on GDMT and won't need an ICD. Premature ICD in a recovered patient is a permanent device they didn't need.
EF recovers > 35%: continue GDMT lifelong (do NOT stop; TRED-HF showed 40% relapse rate within 6 months of withdrawal). No ICD.
EF stays ≤ 35%, NYHA II-III on optimized GDMT for ≥ 3 months: primary-prevention ICD (Class I).
EF ≤ 35% + LBBB ≥ 150 ms + NYHA II-IV:CRT-D (strongest indication; Class I).
Step 5: Add-on therapies if persistent symptoms despite optimized 4-pillar
Drug
When to Add
Why
Hydralazine + ISDN
Self-identified Black patients, NYHA III-IV on optimized GDMT
A-HeFT (2004): 43% mortality reduction in Black patients added to ACEi/BB. Class I in this population.
Ivabradine (Corlanor)
NSR with HR ≥ 70 despite max-tolerated BB, NYHA II-III, EF ≤ 35%
SHIFT (2010): 18% reduction in CV death/HF hospitalization. Funny-current (If) inhibitor in SA node; only works in NSR. Class IIa.
Vericiguat (Verquvo)
Recent worsening HF (hospitalization or IV diuretic) despite optimized GDMT
VICTORIA (2020): 10% reduction in CV death/HF hospitalization in high-risk worsening-HF patients. Soluble guanylate cyclase stimulator. Class IIb.
Digoxin
Persistent symptoms despite all above, or AF rate control overlay
DIG trial: no mortality benefit but reduces HF hospitalization. Narrow therapeutic window (target 0.5-0.9 ng/mL); higher levels increase mortality.
IV iron (ferric carboxymaltose)
Iron deficiency (ferritin < 100, or 100-299 with TSAT < 20%)
AFFIRM-AHF (2020): 26% reduction in HF hospitalization at 52 weeks. Treat even if Hb is normal -iron deficiency in HF is symptomatic without anemia.
Step 6: Advanced therapies (refractory NYHA IV)
Refer to advanced HF / transplant program early if any of: persistent NYHA IV symptoms, recurrent admissions, intolerance to GDMT, escalating diuretic doses, SBP < 90 limiting GDMT, INTERMACS profile 1-3, peak VO₂ < 14 mL/kg/min. Options: LVAD (bridge to transplant, bridge to candidacy, or destination therapy), heart transplant, palliative inotropes (dobutamine, milrinone) for symptom relief in end-stage.
Shortcuts that override the ladder
Scenario
Do This
Why
Cardiogenic shock (SBP < 90, on pressors)
Hold all 4 pillars; continue loop diuretic at adjusted dose. Resume sequentially once off pressors and Cr stable.
Each pillar drops BP, blunts SNS, or worsens hemodynamics in shock. Restart in order: ACEi/ARB/ARNI → BB → MRA → SGLT2i.
AKI with Cr rise > 30% from baseline
Hold ACEi/ARB/ARNI and MRA; continue SGLT2i and BB (SGLT2i Cr bump is hemodynamic and reverses)
RAAS-blockade and MRA cause true GFR drop that doesn't reverse if pushed; SGLT2i bump is intraglomerular pressure normalization (renoprotective long-term).
MRA mortality benefit is lost if discontinued. Binders preserve GDMT. Class IIa in the 2022 guideline.
SBP < 90 limiting titration
Prioritize BB and SGLT2i (less BP-dependent for mortality benefit); use lower-dose ARNI or hold ARNI; reduce non-GDMT BP-lowering agents (CCBs, alpha-blockers).
BB and SGLT2i mortality benefit holds at lower BPs. Don't abandon mortality drugs to chase a BP number.
HR < 55 or symptomatic bradycardia
Hold further BB uptitration; reassess for AV block; consider ivabradine if NSR and HR remains ≥ 70 at max-tolerated BB later
BB still has mortality benefit at submaximal doses (don't abandon it). Bradycardia at low BB dose may unmask underlying conduction disease.
Active decompensation (admitted, congested, on IV diuretic)
Don't initiate BB; continue if already on it (B-CONVINCED). OK to initiate ARNI/ACEi/MRA/SGLT2i if hemodynamically stable.
Negative inotropy of BB in a wet patient worsens cardiac output and congestion. Once euvolemic and stable, start BB before discharge.
HFpEF (EF ≥ 50%)
SGLT2i first (EMPEROR-Preserved, DELIVER), then consider MRA (TOPCAT signal in Americas), diuretic for congestion. Treat HTN, AF, OSA, obesity aggressively.
HFpEF has no ARNI/BB mortality benefit. SGLT2i is the only class with clean HFpEF outcome data. Class I (SGLT2i) in 2023 focused update.
HFmrEF (EF 41-49%)
Treat as HFrEF -all 4 pillars (Class IIa in 2022 guideline)
Pooled data and DELIVER subgroup show similar benefit to HFrEF. Don't undertreat just because EF is borderline.
The Four Pillars of HFrEF
All four pillars should be initiated and uptitrated in every HFrEF patient (EF ≤ 40%) unless contraindicated. Each independently reduces mortality. Together, they reduce HF mortality by ~70% compared to no treatment. Get them all on board -don't wait to finish one before starting the next.
Pillar
Drug (Brand)
Target Dose
Key Trial
Mortality Reduction
Watch Out
1. ARNI* *= Angiotensin Receptor-Neprilysin Inhibitor (sacubitril-valsartan) 1ST LINE
Only these three BBs are evidence-based for HFrEF. Atenolol, propranolol, etc. have no HF data. Start low, go slow. Do NOT start during decompensation.
3. MRA* *= Mineralocorticoid Receptor Antagonist (spironolactone, eplerenone) 1ST LINE
~25% reduction in CV death + HF hospitalization. Benefit independent of diabetes status.
Expect a ~0.2 Cr bump when starting (hemodynamic, not injury, reverses). Avoid if eGFR < 20 or T1DM (euglycemic DKA risk). Watch for GU mycotic infections. Hold peri-operatively or if NPO for > 24h.
🫀 HFrEF vs HFpEF
HFrEF vs HFpEF -Management Comparison
Classification: HFrEF = EF ≤ 40% | HFmrEF = EF 41–49% | HFpEF = EF ≥ 50%. Management differs fundamentally -HFrEF has strong mortality-reducing GDMT; HFpEF treatment is largely symptom-driven with emerging evidence for SGLT2 inhibitors.
Diastolic dysfunction -stiff ventricle. Normal LV size, impaired relaxation and filling.
ARNI / ACEi / ARB
MORTALITY BENEFIT ARNI preferred over ACEi/ARB. PARADIGM-HF, 2014: sacubitril/valsartan reduced CV death + HF hospitalization by 20% vs enalapril.
NO PROVEN BENEFITPARAGON-HF, 2019: ARNI did not significantly reduce primary endpoint vs valsartan. Possible benefit in lower EF range (EF ≤ 57%).
Beta-blocker
MORTALITY BENEFIT Carvedilol, metoprolol succinate, or bisoprolol. COPERNICUS, 2001: carvedilol reduced mortality 35% in severe HFrEF. MERIT-HF, 1999: metoprolol succinate reduced mortality 34%.
NO PROVEN BENEFIT No mortality benefit in HFpEF trials. Use for rate control (Afib) or HTN -not as HF-specific therapy.
MRA
MORTALITY BENEFITRALES, 1999: spironolactone reduced mortality 30% in severe HFrEF. EPHESUS, 2003: eplerenone in post-MI HFrEF.
POSSIBLE BENEFITTOPCAT, 2014: overall negative, but Americas subgroup showed benefit. Consider if symptomatic despite diuretics.
SGLT2 inhibitor
MORTALITY BENEFITDAPA-HF, 2019: dapagliflozin reduced worsening HF/CV death 26%. EMPEROR-Reduced, 2020: empagliflozin confirmed class effect.
HF HOSPITALIZATION BENEFITEMPEROR-Preserved, 2021: empagliflozin reduced CV death + HF hospitalization 21%. DELIVER, 2022: dapagliflozin confirmed across EF spectrum. Only drug class with clear benefit in HFpEF.
Diuretics
Symptom relief. Loop diuretics for congestion. No mortality benefit but essential for decongestion.
Cornerstone of symptom management. Low-dose loop diuretics. Avoid over-diuresis -these patients are preload-dependent.
GLP-1 RA
No specific HFrEF indication. Use for comorbid T2DM/obesity.
EMERGINGSTEP-HFpEF, 2023: semaglutide improved symptoms, exercise capacity, and weight in obese HFpEF. Targets the obesity-HFpEF phenotype.
Comorbidity focus
ICD/CRT if EF ≤ 35% on optimal GDMT × 3 months. Cardiac rehab. Iron repletion if deficient.
Central to management. Aggressive HTN control, Afib rate control (restore atrial kick), weight loss, OSA treatment, glycemic control, exercise training. Ex-DHF, 2011: exercise training improved peak VO₂ and quality of life.
Devices
ICD if EF ≤ 35% + NYHA II–III on optimal GDMT ≥ 3 months (SCD-HeFT, 2005). CRT if EF ≤ 35% + LBBB + QRS ≥ 150ms.
No role for ICD or CRT. EF is preserved -sudden death risk is lower.
Key takeaway: HFrEF has 4 mortality-reducing drug classes (ARNI, BB, MRA, SGLT2i) -start all four early and titrate to targets. HFpEF management centers on SGLT2 inhibitors (the only drug class with clear evidence), aggressive diuresis for symptoms, and treating every comorbidity (HTN, obesity, Afib, DM, OSA). The days of "nothing works for HFpEF" are over -SGLT2i changed the game.
🔧 Device Therapy
ICD (Implantable Cardioverter-Defibrillator)
Primary prevention ICD indications in HFrEF:
EF ≤ 35% despite ≥ 3 months of optimal GDMT
NYHA class II–III
Expected survival > 1 year
Wait ≥ 40 days post-MI and ≥ 90 days post-revascularization before implant MADIT-II, 2002SCD-HeFT, 2005
Secondary prevention: Any survivor of VT/VF arrest or sustained VT with hemodynamic compromise → ICD regardless of EF.
CRT (Cardiac Resynchronization Therapy)
EF ≤ 35% + LBBB with QRS ≥ 150 ms + NYHA II–IV on optimal GDMT → strongest indication (class I)
LBBB with QRS 120–149 ms → class IIa
Non-LBBB with QRS ≥ 150 ms → class IIa (weaker benefit)
QRS < 120 ms → NO benefit from CRT
MADIT-CRT, 2009: CRT-D reduced HF events by 34% in LBBB patients. RAFT, 2010: CRT-D reduced mortality by 25% vs ICD alone in LBBB.
Advanced HF -When to Refer
NYHA III–IV despite maximal GDMT
≥ 2 HF hospitalizations in 12 months
Rising BNP/NT-proBNP despite optimization
Refractory volume overload requiring frequent IV diuretics
Declining renal function (cardiorenal syndrome)
Consideration for LVAD (bridge to transplant or destination therapy) or heart transplant
📋 On Rounds
Pimp Questions
What are the four pillars of HFrEF GDMT?
(1) ARNI (sacubitril/valsartan) or ACEi/ARB, (2) evidence-based beta-blocker (carvedilol, metoprolol succinate, or bisoprolol -only these three), (3) MRA (spironolactone or eplerenone), (4) SGLT2 inhibitor (dapagliflozin or empagliflozin). All four independently reduce mortality. Together, ~70% mortality reduction.
Why is sacubitril/valsartan (Entresto) better than enalapril?
PARADIGM-HF, 2014: sacubitril/valsartan reduced CV death by 20% and HF hospitalization by 21% compared to enalapril. Sacubitril is a neprilysin inhibitor -it prevents breakdown of natriuretic peptides (BNP, ANP) → enhanced natriuresis, vasodilation, and neurohormonal modulation. Must hold ACEi × 36h before switching (angioedema risk from dual enzyme inhibition).
Which beta-blockers are evidence-based in HFrEF?
Only three: carvedilol COPERNICUS, 2001, metoprolol succinate MERIT-HF, 1999, and bisoprolol CIBIS-II, 1999. Atenolol, propranolol, metoprolol tartrate, and other beta-blockers have NO evidence for mortality reduction in HFrEF. Metoprolol tartrate ≠ metoprolol succinate -the succinate (extended release) formulation is the one with the trial data.
What was the first drug to show benefit in HFpEF?
SGLT2 inhibitors. EMPEROR-Preserved, 2021: empagliflozin reduced HF hospitalization by 21% in HFpEF. DELIVER, 2022: dapagliflozin reduced HF composite by 18%. Before this, decades of trials failed in HFpEF -ACEi, ARBs, digoxin, and spironolactone all showed no or equivocal mortality benefit. SGLT2i are now first-line for all HF regardless of EF.
When do you refer for ICD vs CRT?
ICD: EF ≤ 35% despite ≥ 3 months GDMT, NYHA II–III, expected survival > 1 year. Wait ≥ 40 days post-MI. CRT: same EF criteria PLUS LBBB with QRS ≥ 150 ms (strongest indication). Non-LBBB or QRS 120–149 have weaker evidence. QRS < 120 ms = no CRT benefit. Most patients who qualify for CRT also get a combined CRT-D (CRT + defibrillator).
Clinical Examples
📋 Case 1, New HFrEF Diagnosis: Initiating GDMT
Patient: 55M with HTN and T2DM, presents with 3 weeks of progressive dyspnea on exertion, orthopnea (3-pillow), and bilateral leg swelling. No prior cardiac history.
Key findings: BP 142/88, HR 92, SpO2 95% on RA, JVD, bilateral crackles to mid-lung, 2+ pitting edema. BNP 1,840. Echo: EF 25%, global hypokinesis, no significant valvular disease. Troponin negative x2.
Management:
IV furosemide 40 mg q12h for decongestion, daily weights, strict I/Os, Na < 2g/day
Check BMP in 1 week (K+ and Cr on ARNI + MRA). Hold MRA if K+ > 5.0 or eGFR < 30
Uptitrate ARNI and BB at 2-week intervals to target doses as tolerated
Teaching point: Current guidelines favor starting all 4 GDMT pillars early rather than sequential addition. SGLT2i can be started regardless of diabetes status. The STRONG-HF, 2022 trial showed rapid uptitration is safe and improves outcomes.
📋 Case 2, Acute Decompensated HF with Cardiogenic Shock
Patient: 68F with known HFrEF (EF 20%), on sacubitril/valsartan, carvedilol, spironolactone, and dapagliflozin. Presents with worsening dyspnea at rest x 2 days, unable to lie flat.
Key findings: BP 82/54, HR 110, SpO2 88% on 4L NC, cool extremities, mottled skin. Lactate 4.2. BNP 5,600. CXR: pulmonary edema. PA catheter: CI 1.6, PCWP 32, SVR 2,100 ("cold and wet" profile).
Management:
Hold BB, ARNI, MRA in acute cardiogenic shock (restart once hemodynamically stable)
IV milrinone (preferred if on chronic BB -- does not compete with beta receptors) or dobutamine for inotropy
IV furosemide drip (double home dose) for decongestion once perfusion improves
If refractory: consider mechanical circulatory support (Impella, IABP). Cardiology and CT surgery consult
Teaching point: In cardiogenic shock, hold all GDMT that lowers BP or HR. The "cold and wet" profile requires inotropes before diuresis. Use the Stevenson classification (warm/cold, wet/dry) to guide management.
📋 Case 3, HFpEF with Recurrent Admissions
Patient: 74F with obesity (BMI 38), HTN, T2DM, and Afib, presents with third HF admission in 6 months. Dyspnea on minimal exertion, 8 lb weight gain over 2 weeks despite taking furosemide 40 mg daily at home.
Key findings: BP 158/92, HR 84 (irregular), SpO2 93% on RA, elevated JVP, bibasilar crackles, 3+ edema. BNP 680. Echo: EF 62%, grade II diastolic dysfunction, moderate TR, RVSP 52. H2FPEF score: 8 (high probability of HFpEF).
Management:
IV diuresis: furosemide 80 mg IV BID (double oral dose for IV). Target net negative 1-2 L/day
Start empagliflozin 10 mg daily -- first drug class with proven benefit in HFpEF EMPEROR-Preserved, 2021
Aggressive BP control (target < 130/80), rate control for Afib (target HR < 110), weight loss counseling
Consider spironolactone 25 mg daily (reduces HF hospitalizations in HFpEF per TOPCAT, 2014 Americas subgroup)
Teaching point: SGLT2 inhibitors are the first drug class to show clear benefit across the entire EF spectrum. In HFpEF, focus on treating comorbidities (HTN, obesity, Afib, volume status) since no other drug has proven mortality benefit.
📣 Sample Presentation
One-Liner
"Mr. Lopez is a 62-year-old with HFrEF (EF 30%), NYHA class II, currently on lisinopril 10 mg, carvedilol 12.5 BID, and furosemide 40 daily. Not on MRA or SGLT2i. Here for medication optimization."
Key Points to Cover on Rounds
EF 30%, NYHA II, currently on 2 of 4 GDMT pillars. Action plan: (1) Switch lisinopril → sacubitril-valsartan 24/26 BID (must wash out ACEi ×36h first), (2) Uptitrate carvedilol to 25 mg BID in 2 weeks, (3) Add spironolactone 25 mg daily (K⁺ 4.2, Cr 1.1 -safe), (4) Add dapagliflozin 10 mg daily. ICD candidacy: EF ≤ 35% on max GDMT ×3 months → reassess. CRT if LBBB + QRS ≥ 150. Cardiac rehab referral.
Monitoring Parameters -Chronic Heart Failure
Parameter
Frequency
Target / Action
Daily weights
Every morning, same scale, before breakfast
Weight gain > 2 lbs in 2 days or > 5 lbs in 1 week → call clinic / increase diuretic per action plan. Most important home monitoring tool.
BMP (K⁺, Cr, Na⁺)
1–2 weeks after each GDMT initiation or dose change; then q3–6 months when stable
SBP ≥ 90 for ARNI/ACEi/ARB titration. Tolerate asymptomatic low SBP (90–100) if on optimal GDMT. Symptomatic hypotension → reduce diuretic first, then GDMT.
Heart rate
Each clinic visit
Resting HR 60–70 on maximally tolerated beta-blocker. HR ≥ 70 despite max BB → consider ivabradine (if sinus rhythm, EF ≤ 35%).
BNP / NT-proBNP
Baseline, then to track response to therapy
> 30% reduction from baseline = good prognostic sign. Do not chase a specific number -trend matters more than absolute value. If on sacubitril/valsartan (Entresto), trend NT-proBNP, not BNP -neprilysin inhibition falsely elevates BNP, while NT-proBNP is unaffected. Why ↗
Echocardiogram (EF)
Repeat at 3–6 months after GDMT optimization
EF improvement → continue all GDMT (may reclassify HFrEF → HFimpEF). LBBB + EF ≤ 35% + QRS > 150 ms → CRT candidate.
Ferritin < 100 or ferritin 100–300 + TSAT < 20% → IV iron replacement. Improves functional capacity and reduces HF hospitalizations.
GDMT uptitration is the priority. At every visit, ask: "Can I increase any of the four pillars?" Uptitrate one drug at a time, every 1-2 weeks, to target dose or maximally tolerated dose. Do NOT wait for one pillar to be at target before starting the next - initiate all four early and uptitrate in parallel STRONG-HF, 2022.
🧪 Workup
Workup -Chronic Heart Failure
Echocardiogram -the single most important test. Establishes EF (HFrEF vs HFpEF vs HFmrEF), wall motion abnormalities, valvular disease, diastolic dysfunction, chamber sizes. Repeat at 3–6 months after GDMT optimization to reassess EF.
BNP / NT-proBNP -elevated in HF (BNP > 100, NT-proBNP > 300). Useful for diagnosis, prognosis, and monitoring response to therapy. Trend over time -> 30% reduction with treatment is a good prognostic sign. On an ARNI (sacubitril/valsartan, Entresto), monitor with NT-proBNP -BNP is falsely raised by neprilysin inhibition, NT-proBNP is not a neprilysin substrate.
BMP -baseline Cr, K⁺, Na⁺ before starting RAAS inhibitors and diuretics. Monitor after each dose change. Cr rise ≤ 30% acceptable on ACEi/ARB/ARNI. K⁺ must be < 5.0 for MRA initiation.
CBC -anemia worsens HF symptoms and is common (anemia of chronic disease, hemodilution). Iron studies if anemic -IV iron if ferritin < 100 or ferritin 100–300 + TSAT < 20% AFFIRM-AHF, 2020
TSH -hypo- and hyperthyroidism are reversible causes of HF. Check in all new diagnoses.
Iron studies -ferritin and TSAT. Iron deficiency is common in HF and independently worsens exercise capacity and outcomes, even without anemia.
ECG -LVH, prior MI, arrhythmia (AF common), conduction disease (LBBB -CRT candidate if QRS > 150 ms + EF ≤ 35%).
Cardiac MRI -if echo is inadequate, or to characterize etiology (ischemic vs non-ischemic, infiltrative, myocarditis, hemochromatosis, amyloid).
💊 Medications
Medications -Chronic Heart Failure (HFrEF)
All four pillars should be initiated in every HFrEF patient (EF ≤ 40%). See the GDMT (Four Pillars) tab above for detailed dosing, trials, and titration guidance.
Pillar
Drug (Brand)
Starting → Target Dose
Key Monitoring
1. ARNI
Sacubitril/valsartan (Entresto)
24/26 mg BID → 97/103 mg BID
BP, Cr, K⁺ at 1–2 weeks. Hold ACEi 36h before starting. SBP ≥ 90.
2. Beta-blocker
Carvedilol (Coreg) or metoprolol succinate (Toprol-XL)
No titration needed. Works in diabetic AND non-diabetic HF. Watch for GU infections, euglycemic DKA (rare).
Additional Agents
Diuretics -furosemide (Lasix) for volume management. Symptom relief only -no mortality benefit. Titrate to dry weight.
Hydralazine/isosorbide dinitrate (BiDil) -add to GDMT in Black patients with NYHA III–IV (A-HeFT, 2004). Also for patients who cannot tolerate ACEi/ARB/ARNI.
Ivabradine (Corlanor) -if HR ≥ 70 on maximally tolerated beta-blocker, sinus rhythm, EF ≤ 35% SHIFT, 2010.
IV iron -ferric carboxymaltose (Injectafer) if ferritin < 100 or ferritin 100–300 + TSAT < 20%. Improves symptoms and reduces HF hospitalizations.
DIGIT-HF (NEJM 2025): Digitoxin 0.07 mg daily added to GDMT reduced the composite of death + HF hospitalization by 18% (HR 0.82, p=0.03) in advanced HFrEF (LVEF ≤40%, NYHA III-IV). Benefits consistent even on ARNI + SGLT2i. Consider after optimizing all four pillars. DIGIT-HF, 2025 Note: the older DIG, 1997 trial showed digoxin reduced HF hospitalizations 28% but had no mortality benefit.
⚡ Management
Management -Chronic Heart Failure
See the GDMT (Four Pillars) tab for the full treatment algorithm with drug dosing, target doses, and landmark trial citations. See the HFrEF vs HFpEF tab for a side-by-side management comparison. For acute decompensation management, see ADHF.
Iron Deficiency in HF -Different Cutoffs Than General Population
Iron deficiency affects up to 50% of HF patients (with or without anemia) and is independently associated with worse exercise capacity, quality of life, and HF hospitalization. The diagnostic thresholds in HF are different from the general population -ferritin is an acute-phase reactant, and chronic systemic inflammation in HF inflates it, masking true iron deficiency.
Population
Iron deficiency definition
Why this threshold
General adult
Ferritin < 30 ng/mL OR TSAT < 20% with ferritin < 100
Standard ID threshold; no inflammation correction needed.
Chronic inflammation in HF elevates ferritin (acute-phase reactant). A "normal" ferritin (e.g., 80 ng/mL) in HF can mask iron-depleted stores. TSAT < 20% is more reliable -less affected by inflammation.
Practical lab combo to check in HF: ferritin + TSAT + serum iron + TIBC. Iron-saturation ratio (TSAT) catches the functional iron deficiency that ferritin alone misses. Don't be reassured by ferritin 50-150 in a HF patient with persistent fatigue and exercise intolerance -check TSAT.
What is TSAT (Transferrin Saturation), and why does it matter so much in HF? The percentage of transferrin (the iron-carrying transport protein) that is currently bound to iron. Formula: TSAT = (serum iron ÷ TIBC) × 100. Normal range: 20-50%. Iron deficiency: < 20%.
Why TSAT > ferritin in HF specifically: ferritin is a storage marker AND an acute-phase reactant -it rises with inflammation. HF is a state of chronic systemic inflammation, so a "normal-looking" ferritin (e.g., 80-150 ng/mL) can mask depleted iron stores. TSAT reflects circulating iron available for cardiomyocyte and skeletal-muscle mitochondria right now, and is much less inflated by inflammation. That's why the HF iron-deficiency definition explicitly includes TSAT < 20% as a functional criterion -it catches the patient who looks fine on ferritin alone but is functionally iron-starved.
Pre-test pearls: hold oral iron for 24-48 h before draw (recent dose falsely elevates TSAT). TSAT has diurnal variation (higher in AM) -fasting AM draw is most reliable for borderline cases.
Who to give iron to
HFrEF (EF ≤ 40%) AND iron-deficient (per HF criteria above) AND symptomatic (NYHA II-IV) -Class 2a per ACC/AHA 2022 and ESC 2023.
HFmrEF (EF 41-49%) -reasonable based on extrapolation; trial data sparser.
HFpEF (EF ≥ 50%) -individualize. Trials predominantly enrolled HFrEF; HFpEF iron data still emerging.
Acute HF admission with iron deficiency -AFFIRM-AHF, 2020 supports IV iron BEFORE discharge to reduce HF rehospitalization.
What to give -IV iron, not oral
Oral iron is generally ineffective in HF. Chronic inflammation drives high hepcidin → blocks intestinal iron absorption AND blocks iron release from stores. IRONOUT-HF, 2017 showed oral iron polysaccharide did NOT improve exercise capacity. Use IV iron.
Drug
Dose
Notes
Ferric carboxymaltose (Injectafer) PREFERRED
Up to 1000 mg IV per dose, max 1500 mg per cycle. Repeat in 3-6 mo if depleted.
Most-studied IV iron in HF (FAIR-HF, CONFIRM-HF, AFFIRM-AHF, HEART-FID). Watch transient hypophosphatemia (especially with repeat dosing).
Ferric derisomaltose (Monoferric) SINGLE-INFUSION
Up to 1500 mg IV in one dose (over 20-30 min)
IRONMAN, 2022 showed clinical-event reduction. Convenient single infusion. Less hypophosphatemia than ferric carboxymaltose.
Iron sucrose (Venofer) OLDER
200 mg IV per dose, multiple infusions needed
Older agent, requires more infusions (5-10 visits to repleting). Less convenient. Use only if newer agents unavailable.
Why give iron in HF -what does it actually do?
Improves exercise capacity (6-minute walk distance, peak VO₂) -CONFIRM-HF, 2015
Improves quality of life and NYHA class -FAIR-HF, 2009
Mechanism: iron is essential for mitochondrial function in cardiomyocytes and skeletal muscle. Repletion improves cellular energetics independent of correcting anemia.
Bottom line for rounds: In any HFrEF patient with NYHA II-IV symptoms, check ferritin + TSAT. Use the HF-specific cutoffs (ferritin < 100 absolute, OR ferritin 100-299 + TSAT < 20% functional). If iron-deficient, give IV ferric carboxymaltose 1000 mg (or ferric derisomaltose 1500 mg single dose). Don't bother with oral iron. Recheck labs in 3-6 months.
⚡ Summary
Summary
Start All Four Pillars, and Start Them Early
ARNI (or ACE inhibitor/ARB), beta blocker, mineralocorticoid receptor antagonist, and SGLT2 inhibitor.Begin all four at low dose within days rather than sequentially over months: the mortality benefit is additive and appears within weeks, so a patient on one drug at target dose is worse off than a patient on four at low dose.
Uptitrate on a Schedule, Not on Symptoms
Titrate toward target doses over 4 to 6 weeks with a defined follow-up plan.STRONG-HF showed rapid uptitration with close follow-up reduces death and readmission.The commonest failure in heart failure care is a patient left on starting doses indefinitely because nobody owned the titration.
Know What Each Pillar Buys
ARNI beats ACE inhibitor on mortality (PARADIGM-HF), with a mandatory 36-hour washout from an ACE inhibitor to avoid angioedema. Beta blockers: only carvedilol, metoprolol succinate and bisoprolol have mortality evidence, and they are started when the patient is euvolemic, not while congested. MRAs reduce mortality and need potassium and creatinine checked at 1 and 4 weeks.SGLT2 inhibitors work regardless of diabetes and across the whole ejection fraction range.
Tolerate the Expected Side Effects
A creatinine rise up to about 30% and a modest blood pressure fall are expected and are not reasons to stop.Asymptomatic hypotension is tolerated; symptomatic hypotension means reduce the diuretic first, not the guideline therapy. Stopping the drug at the first abnormal number is how patients end up on nothing.
HFpEF Is a Shorter List
SGLT2 inhibitors are the first therapy with clear benefit (EMPEROR-Preserved, DELIVER). MRAs and ARNI have a role, particularly at the lower end of the preserved range.Otherwise treat the comorbidities: hypertension, atrial fibrillation, obesity, sleep apnea and coronary disease, which is where most of the modifiable risk sits. Diuretics for symptoms in both phenotypes, but they do not change mortality.
Reassess at 3 Months Before Devices
Repeat the echocardiogram after 3 months of optimized therapy.30 to 40% of new HFrEF recovers an ejection fraction above 35% on guideline therapy and never needs an ICD, so implanting early exposes patients to a device they would not have needed. ICD for EF 35% or below after that period, with a life expectancy above 1 year.
CRT Has Its Own Criteria
EF 35% or below, sinus rhythm, and a QRS of 150 ms or more with LBBB morphology, in NYHA class II to IV on optimal therapy.The benefit is greatest with LBBB and a wide QRS, and it is much weaker with a non-LBBB pattern or a narrower QRS, where implanting adds risk without clear benefit.
Recognize When to Refer for Advanced Therapy
I-NEED-HELP: inotropes, NYHA class IV, end-organ dysfunction, EF 20% or below, defibrillator shocks, hospitalizations, escalating diuretics, low blood pressure, prognostic markers worsening. Refer before the patient is too sick for transplant or a durable device, since late referral is the commonest reason these options are lost. Also address iron deficiency (IV iron improves symptoms even without anemia), vaccination, sodium and fluid education, daily weights and cardiac rehabilitation.
IV furosemide 1-2.5× home dose. Target net −1 to 2L/day. Metolazone for resistance. Avoid inotropes unless cardiogenic shock. Continue GDMT unless hypotensive.
💊 4 GDMT Pillars
(1) ARNI [PARADIGM-HF] or ACEi. (2) BB: carvedilol, metoprolol succinate, or bisoprolol. (3) MRA: spironolactone [RALES]. (4) SGLT2i: dapagliflozin [DAPA-HF] or empagliflozin.
💊 Key Drugs
Furosemide IV40-200 mg bolus
Sacubitril-valsartan24/26 → 97/103 BID
Carvedilol3.125 → 25 mg BID
Spironolactone12.5-50 mg daily
Dapagliflozin10 mg daily
⚠️ Pitfalls
Holding BB in acute HF (continue unless cardiogenic shock)
Not starting all 4 GDMT pillars
Chasing BNP number instead of clinical volume status
Rise in creatinine ≥ 0.3 mg/dL in 48h or ≥ 1.5× baseline in 7 days. Step 1: is it pre-renal, intrinsic, or post-renal? The answer drives everything.
🔍 Overview
2024–2026 Practice Updates
What's changed since the original 2012 KDIGO guideline:
Terlipressin is first-line for HRS-AKI in the US (FDA approved 2022), replaces midodrine + octreotide as the preferred regimen when available. CONFIRM, 2021
Contrast-associated AKI is overestimated. N-acetylcysteine and bicarbonate are not recommended; isotonic saline only for eGFR <30. PRESERVE, 2018 · AMACING, 2017 Don't withhold needed imaging for moderate CKD.
SGLT2 inhibitors: Hold during acute illness / volume depletion, but resume after recovery, they are renoprotective long-term. EMPA-KIDNEY, 2022
Early vs delayed RRT: Watchful waiting is preferred for stage 2/3 AKI without emergent indications. STARRT-AKI, 2020 · AKIKI, 2016
Furosemide stress test (1–1.5 mg/kg IV; UOP <200 mL/2h predicts progression) is now an accepted bedside risk-stratification tool.
Biomarkers (TIMP-2 × IGFBP-7 / NephroCheck): FDA-cleared for early AKI prediction in ICU patients, adoption variable, not yet standard of care.
Patiromer / SZC have replaced SPS (Kayexalate) for non-emergent hyperkalemia, faster onset, lower risk of intestinal necrosis.
First Move: Bladder scan + renal ultrasound (rule out obstruction) -quick, cheap, and you'll miss post-renal without it.
UA with microscopy -RBC casts (GN), waxy/granular casts (ATN), eosinophils (AIN), protein
FENa = (UNa × PCr) / (PNa × UCr) × 100
< 1% = pre-renal or early contrast nephropathy
> 2% = ATN (intrinsic) Note: FEUrea more reliable in patients on diuretics (< 35% = pre-renal)
🔄 Updated Practice: Old teaching: FENa <1% = pre-renal, FENa >2% = intrinsic (ATN). This is unreliable if the patient is on diuretics (which increase FENa regardless of etiology). Use FEUrea instead -it is NOT affected by diuretics. FEUrea <35% = pre-renal, FEUrea >50% = intrinsic. Also: "pre-renal" and "ATN" exist on a spectrum -prolonged pre-renal azotemia leads to ATN. Early volume resuscitation prevents progression.
Timing of Dialysis -Don't Rush. Early initiation of RRT does NOT improve mortality vs a delayed/watchful strategy STARRT-AKI, 2020AKIKI, 2016. Only dialyze when you have a clear AEIOU indication.
Trial
Year
Finding
AKIKI
2016
Early RRT (within 6h of KDIGO 3) vs delayed (watchful waiting for AEIOU indication) in critically ill AKI -no mortality difference. 49% of delayed group never needed dialysis at all.
IDEAL-ICU
2018
Early vs delayed RRT in septic shock with AKI -no benefit. Stopped early for futility. 38% of delayed group avoided RRT entirely.
STARRT-AKI
2020
Largest trial (n=2,927). Accelerated vs standard RRT initiation -no 90-day mortality benefit. Accelerated group had more catheter-related bloodstream infections and hypotension during dialysis.
Bottom line: Wait for a hard AEIOU indication before initiating RRT. Many critically ill AKI patients recover renal function and never require dialysis if given time. Early initiation exposes patients to catheter complications and hemodynamic instability without survival benefit.
🔄 Updated Practice: Old teaching: start dialysis early in AKI to prevent complications. AKIKI 2016 and STARRT-AKI 2020 both showed that delayed/watchful waiting strategy is safe and avoids unnecessary dialysis in ~50% of patients. Only start RRT for absolute indications: refractory hyperkalemia, severe metabolic acidosis, refractory fluid overload, or uremic complications (encephalopathy, pericarditis, bleeding). "The best dialysis is the one you never need to start."
Swipe for more examples
📋 Case 1, AKI Workup Interpretation
Patient: 72M admitted for pneumonia, Cr rising 1.0 → 2.4 over 48h (KDIGO Stage 2)
IV isotonic fluids, NS or LR at 1 mL/kg/hr. Avoid volume overload (monitor lung exam, JVP).
Hold all nephrotoxins, metformin, ACEi, NSAIDs, aminoglycosides.
No more contrast for at least 48–72h. If urgent need → minimize volume + use iso-osmolar contrast.
Expect peak Cr at 3–5 days, recovery over 7–14 days. If no recovery by day 14 → may need nephrology consult.
Key lesson: CKD + contrast = high risk. Pre-hydration with IV NS reduces risk. NAC (N-acetylcysteine) has been debunked, no benefit (PRESERVE trial, 2018).
📋 Case 3, Rhabdomyolysis-Induced AKI
Patient: 34M found down after drug overdose (unknown duration). Cr 4.6 (baseline normal). CK 85,000. Dark tea-colored urine. K⁺ 6.2 with peaked T-waves on ECG.
Pathophysiology: Muscle breakdown → myoglobin released → precipitates in renal tubules → ATN. Also causes massive K⁺ and phosphate release and Ca²⁺ sequestration.
Treatment:
Aggressive IV fluids: NS at 200–300 mL/hr initially. Target UOP > 200–300 mL/hr to flush myoglobin. May need 10–15 L/day.
Monitor CK q6–12h until trending down. Monitor compartment pressures if limb swelling.
Avoid calcium repletion even if Ca²⁺ is low, it deposits in damaged muscle. Only give calcium for symptomatic hypocalcemia or ECG changes.
Dialysis if refractory hyperkalemia, acidosis, or fluid overload despite aggressive IVF.
Key lesson: CK > 5,000 = rhabdo risk for AKI. Flood with fluids early, the best treatment is prevention of tubular precipitation. Always check CK in any "found down" patient.
⚡ Summary
Summary
Define and Stage It
A creatinine rise of 0.3 mg/dL or more within 48 h, or 1.5 times baseline within 7 days, or urine output below 0.5 mL/kg/h for 6 h.KDIGO stages 1 to 3 by creatinine multiple and urine output. The urine output criterion is met before the creatinine moves, so an oliguric patient with a normal creatinine already has AKI.
The Three-Bucket Question Drives Everything
Pre-renal, intrinsic or post-renal.Pre-renal and post-renal are common and reversible, so exclude them first. Intrinsic then splits by compartment: tubular (ATN), interstitial (AIN), glomerular (GN) and vascular.
First Move Is a Bladder Scan and an Ultrasound
Cheap, quick, and you will miss obstruction without it. Post-renal AKI reverses completely if it is relieved early and causes permanent damage if it is not, and a distended bladder in a confused elderly man is easy to overlook on examination.
Use FEUrea, Not FENa, in a Diuresed Patient
The classic FENa below 1% for pre-renal and above 2% for ATN is unreliable on diuretics, which raise FENa regardless of cause. FEUrea is not affected by diuretics: below 35% is pre-renal, above 50% is intrinsic.Always look at the sediment too: muddy brown casts for ATN, white cell casts and eosinophiluria for AIN, red cell casts for glomerulonephritis, bland for pre-renal.
Stop the Insults and Fix the Perfusion
Hold NSAIDs, aminoglycosides, contrast and other nephrotoxins, and renally dose everything else.ACE inhibitors and ARBs are held in the acute setting, though they are not the villain in a well-perfused patient. Give fluid for genuine hypovolemia and stop when the patient is euvolemic: fluid is a treatment for pre-renal AKI, not a treatment for oliguria, and volume overload in established ATN worsens outcomes.
Do Not Rush Dialysis
Early initiation does not improve mortality compared with a watchful strategy (AKIKI, STARRT-AKI), and a delayed strategy avoids dialysis altogether in roughly half of patients. Dialyze for an indication, not for a number.
AEIOU Is the Indication List
Acidosis refractory to medical therapy, Electrolytes (refractory hyperkalemia), Intoxications (methanol, ethylene glycol, lithium, salicylates), Overload refractory to diuretics, Uremia (pericarditis, encephalopathy, bleeding). Refractory is the operative word: each of these means dialysis only after medical management has failed.
Two Practice Changes Worth Knowing
Terlipressin is now first line for hepatorenal syndrome AKI in the US (FDA approved 2022), replacing midodrine plus octreotide where it is available. Contrast-associated AKI has been substantially overestimated, so an indicated scan should not be withheld. Diuretics do not treat AKI: they treat volume overload, and converting oliguric to non-oliguric AKI does not improve survival. Document and follow up, because AKI raises long-term CKD and cardiovascular risk even when the creatinine returns to baseline.
RoundsRx Infographic Series · #9 · Renal & Metabolic · PDF 151 KB
Text version
Nephrology · One Pager
Acute Kidney Injury
Pre-renal, intrinsic, or post-renal. Bladder scan + renal U/S first. FENa localizes the rest. Stop the nephrotoxins.
🚿 Pre-Renal (60–70%)
FENa < 1% / BUN:Cr > 20
Volume depletion, low CO
NSAIDs, ACEi/ARB
Rx: IV fluids, hold nephrotoxins
Cr improves in 24–48h
🔬 Intrinsic (20–30%)
FENa > 2% / muddy brown casts
ATN: ischemia, contrast, aminoglycosides
AIN: drugs (PPIs, NSAIDs, PCN)
GN: RBC casts + proteinuria
Rx: Supportive, avoid nephrotoxins
🚧 Post-Renal (5–10%)
Hydronephrosis on U/S
BPH, bladder outlet obstruction
Ureteral obstruction
Rx: Foley or urology consult
Watch for post-obstructive diuresis
🧮 FENa Calculation
(UNa × PCr) ÷ (PNa × UCr) × 100
< 1% = Pre-renal
> 2% = ATN (intrinsic)
Use FEUrea if on diuretics (< 35% = pre-renal)
🆘 Dialysis Indications -AEIOU
A -Acidosis (pH < 7.1)
E -Electrolytes (refractory K⁺)
I -Ingestion (toxic)
O -Overload (refractory)
U -Uremia (pericarditis, encephalopathy)
📋 On Rounds
Pimp Questions
What is the difference between FENa and FEUrea, and when do you use each?
FENa (fractional excretion of sodium) differentiates pre-renal (< 1%) from intrinsic (> 2%) AKI. However, FENa is unreliable if the patient is on diuretics -diuretics increase sodium excretion even in pre-renal states, giving a falsely elevated FENa. In this case, use FEUrea -urea reabsorption is not affected by diuretics. FEUrea < 35% = pre-renal, > 50% = intrinsic. Rule of thumb: use FENa if no diuretics, use FEUrea if on diuretics.
A patient's creatinine is rising but urine output is normal. Is this still AKI?
Yes -non-oliguric AKI is more common than oliguric AKI. Creatinine reflects GFR, not urine output. The kidneys can still produce urine (especially dilute urine) even when filtration is impaired. In fact, non-oliguric AKI generally has a better prognosis than oliguric AKI because it suggests less severe tubular damage. KDIGO stages AKI by Cr rise OR UOP decrease -you only need one criterion.
What are the indications for emergent dialysis in AKI? Use the mnemonic.
AEIOU:A cidosis (pH < 7.1, refractory to bicarb) · E lectrolytes (hyperkalemia > 6.5 refractory to medical management, or with ECG changes) · I ngestion (toxic alcohols: methanol, ethylene glycol -dialyzable; lithium, salicylate toxicity) · O verload (volume overload refractory to diuretics, especially with pulmonary edema) · U remia (uremic pericarditis, uremic encephalopathy, uremic bleeding). Key: these are indications for emergent dialysis.
How do you differentiate ATN from pre-renal AKI when the patient is on diuretics?
FENa is unreliable on diuretics (falsely elevated -diuretics increase sodium excretion). Use FEUrea instead -urea reabsorption is NOT affected by diuretics. FEUrea < 35% = pre-renal, > 50% = intrinsic (ATN). Other clues: Urine microscopy is the most underused tool -muddy brown granular casts = ATN (renal tubular cell debris). Pre-renal has bland sediment or hyaline casts.
Clinical Examples
📋 Case 1, Pre-renal AKI from Volume Depletion
Patient: 82 y/o F with HTN and DM2, admitted for gastroenteritis with 3 days of vomiting/diarrhea. Home meds: lisinopril, ibuprofen PRN.
Key findings: HR 104, BP 92/58, dry mucous membranes. Cr 3.1 (baseline 1.0), BUN/Cr 32, FENa 0.3%, urine osm 620, bland sediment.
Management:
Hold nephrotoxins: stop lisinopril and ibuprofen (ACEi + NSAID + dehydration = classic triple hit)
Volume resuscitation with LR, reassess Cr at 24-48h
Teaching point: FENa < 1% with concentrated urine (osm > 500) confirms avid sodium retention. The ACEi + NSAID + dehydration combination is the most common iatrogenic cause of pre-renal AKI.
📋 Case 2, ATN with Muddy Brown Casts
Patient: 70 y/o M with CKD3 (baseline Cr 1.8) and DM2, Cr rises to 3.4 at 48h post-contrast CT. On furosemide chronically.
Key findings: UOP 25 mL/hr, FEUrea 58% (FENa unreliable on diuretics), urine microscopy: muddy brown granular casts. KDIGO stage 2.
Management:
Supportive care, no specific treatment reverses established ATN
Avoid further nephrotoxins, dose-adjust renally cleared medications
Maintain euvolemia (ATN does not respond to volume loading)
Monitor for dialysis indications (AEIOU mnemonic)
Teaching point: Use FEUrea when patients are on diuretics. Muddy brown granular casts are pathognomonic for ATN. NAC for contrast prophylaxis was debunked by PRESERVE, 2018.
📋 Case 3, Obstructive AKI Requiring Emergent Intervention
Patient: 65 y/o M with BPH and prostate cancer, presents with anuria x24h, nausea, and confusion. K⁺ 7.1 with peaked T waves.
Urology for nephrostomy tubes if needed; dialysis if refractory hyperkalemia/acidosis
Teaching point: Always get renal ultrasound in AKI to rule out obstruction, the most readily treatable cause. Post-obstructive diuresis causes massive electrolyte losses; monitor BMP q6h and replace IVF at 50-75% of UOP.
📣 Sample Presentation
One-Liner
"Mrs. Adams is a 70-year-old with DM and HTN admitted for pneumonia, found to have Cr rise from baseline 1.0 to 2.8 (KDIGO stage 2). FENa 0.4%, bland urine sediment. Likely pre-renal from volume depletion."
Key Points to Cover on Rounds
Baseline Cr 1.0, now 2.8 (KDIGO stage 2). FENa 0.4% (pre-renal). UA: no casts, no protein. Renal US: no hydronephrosis. Nephrotoxins held: lisinopril, ibuprofen stopped on admission. Volume resuscitation with LR ongoing. UOP improving 20→55 mL/hr. Cr trending 2.8→2.4. Plan: continue fluids, recheck BMP PM, restart ACEi only after Cr returns to baseline.
AKI Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
💊 Medications
AKI Medications, Frequency Ordered
Most AKI is managed by stopping nephrotoxins, restoring perfusion, and treating the underlying cause, not by adding drugs. The drugs below are for specific complications, not for "treating AKI" itself. Always renal-dose and review the med list daily.
Hyperkalemia Bundle (most common AKI emergency)
Drug
Dose
Onset / Notes
Calcium gluconate 10%
1–2 g IV over 2–5 min (or CaCl₂ via central line)
1–3 min · membrane stabilization · K>6.5 or any ECG change
Insulin regular + D50
10 u IV + 25 g dextrose (check glc, recheck q1h ×4)
15–30 min · drops K ~0.6–1.0 · hypoglycemia common, especially in AKI
Albuterol nebulizer
10–20 mg neb (4–8× the asthma dose)
15–30 min · drops K ~0.5–1.0 · additive to insulin
Sodium bicarbonate
50–150 mEq IV (only if acidemic, pH <7.2)
Slow · best when AKI + metabolic acidosis · avoid in volume overload
Loop diuretic
Furosemide 40–80 mg IV (higher if known CKD)
Only if making urine · potassium-wasting
Patiromer / SZC
Patiromer 8.4 g PO daily · SZC 10 g PO TID ×48h then daily
Hours · for non-emergent K removal · bridge to definitive therapy
Hemodialysis
Emergent
Definitive · refractory hyperK, ESRD, or AEIOU criteria
Avoid SPS (Kayexalate) in AKI, slow onset, intestinal necrosis risk, and patiromer/SZC are safer and faster.
Diuretics in AKI
Drug
Dose
Use
Furosemide
40–80 mg IV bolus, double q2h to max 200 mg; or drip 5–20 mg/h
Volume overload only · does NOT prevent or treat AKI itself KDIGO
Bumetanide
1–2 mg IV (≈40 mg furosemide)
Alternative if furosemide allergy or poor response
"Furosemide stress test" (1–1.5 mg/kg IV): urine output <200 mL over 2 h predicts progression to stage 3 AKI / RRT need.
Hepatorenal Syndrome – AKI (HRS-AKI)
Drug
Dose
Notes
TerlipressinCONFIRM, 2021
0.5–2 mg IV q4–6h (or continuous infusion)
First-line in US since FDA approval 2022. Hold for hypoxemia (SpO₂ <90%), black-box respiratory failure risk
Albumin 25%
1 g/kg day 1 (max 100 g), then 20–40 g/day
Always paired with terlipressin / midodrine + octreotide
Midodrine + Octreotide
Mido 7.5–12.5 mg PO TID + Oct 100–200 mcg SC TID
Alternative if terlipressin unavailable / contraindicated
Norepinephrine
0.5–3 mg/h IV
ICU alternative · titrate to MAP increase ≥10 mmHg
Common Drugs to STOP or Renal-Dose
Stop immediately: NSAIDs, ACEi/ARB (during active AKI), aminoglycosides, IV contrast (when avoidable), SGLT2i (hold during acute illness), metformin (lactic acidosis risk if eGFR <30)
Dose-adjust: Vancomycin (trough or AUC-guided), pip-tazo (extended infusion), cefepime (neurotoxicity at high levels in AKI), LMWH (switch to UFH if CrCl <30), DOACs, gabapentin/pregabalin, opioids (avoid morphine, codeine)
Hold and reassess: Diuretics if pre-renal · spironolactone/eplerenone (hyperkalemia) · trimethoprim, tacrolimus (creatinine bumps)
Resume after recovery: ACEi/ARB and SGLT2i once Cr stable and patient euvolemic, both are renoprotective long-term
Contrast-Associated AKI Prophylaxis
2024 reframing: True contrast nephropathy is far rarer than once thought. AMACING 2017 / PRESERVE 2018 Don't withhold needed contrast for moderate CKD.
Isotonic saline 1–1.5 mL/kg/h ×6–12h before and after, only for eGFR <30 or AKI
N-acetylcysteine: NOT recommended (PRESERVE), abandon this reflex order
Bicarbonate infusion: NOT recommended over saline
SGLT2i / metformin: Hold the day of contrast, resume 48 h later if Cr stable
Adjuncts & Specific Scenarios
Sodium bicarbonate for severe metabolic acidosis (pH <7.2), BICAR-ICU, 2018
Rasburicase 0.2 mg/kg IV ×1 for tumor lysis syndrome with uric acid >8 (screen for G6PD)
Plasma exchange for TTP, anti-GBM, ANCA vasculitis with rapidly progressive GN
High-dose steroids for biopsy-proven AIN (after stopping the offending drug), prednisone 1 mg/kg taper
Calcitriol / phosphate binders: Reserve for prolonged AKI with CKD-MBD features, not routine
Renal Dosing Quick Reference
For specific CrCl-based dosing of antibiotics, anticoagulants, and analgesics, see Antibiotic Guide · Drug Interactions · Calculators (CrCl).
NephrologyChronicCommon
Chronic Kidney Disease (CKD)
Progressive, irreversible loss of nephron function over months to years. Management centers on slowing progression (RAAS blockade + SGLT2i), treating complications (anemia, bone-mineral disease, acidosis), and timely dialysis planning.
🔍 Overview
Definition
CKD is defined as abnormalities of kidney structure or function present for > 3 months with health implications. Requires either GFR < 60 mL/min/1.73m² OR markers of kidney damage (albuminuria, hematuria, structural abnormality, history of transplant) -or both. Classified by GFR stage (G1–G5) and albuminuria category (A1–A3).
Both GFR and albuminuria independently predict progression and cardiovascular risk. A patient with G2 + A3 is higher risk than G3a + A1. Always classify both.
Etiology (Most Common → Least)
Cause
% of ESKD
Key Features
Diabetes mellitus
~45%
Most common cause worldwide. Nodular glomerulosclerosis (Kimmelstiel-Wilson). Progressive albuminuria → nephrotic range.
Hypertension
~28%
Hypertensive nephrosclerosis. Arteriolar thickening → ischemic nephron loss. Often coexists with DM.
Glomerulonephritis
~8%
IgA nephropathy (most common GN globally), FSGS, membranous, lupus nephritis. Active sediment (RBC casts).
Polycystic kidney disease (ADPKD)
~5%
Autosomal dominant. Bilateral enlarged cystic kidneys on imaging. Family history. Tolvaptan slows progression TEMPO 3:3, 2012.
Regardless of cause, CKD follows a common final pathway: initial injury → nephron loss → compensatory hyperfiltration in remaining nephrons → glomerular hypertension → progressive glomerulosclerosis → further nephron loss → cycle continues. RAAS activation drives this cycle -which is why ACEi/ARBs are foundational therapy. SGLT2 inhibitors reduce intraglomerular pressure by restoring tubuloglomerular feedback (constricting the afferent arteriole).
Key concept:After ~50% nephron loss, progression becomes self-sustaining even if the original insult is removed. This is why early intervention (BP control, RAAS blockade, SGLT2i) is critical -you're trying to break the hyperfiltration cycle before it becomes irreversible.
Presentation
Early (G1–G3a): Usually asymptomatic. Detected incidentally on labs (elevated Cr, proteinuria on UA).
Family history of kidney disease → ADPKD (US), Alport syndrome (genetic testing)
Young patient with CKD → always pursue cause (GN, reflux, congenital)
Small bilateral kidneys (< 9 cm) on US = chronic, irreversible. Biopsy is usually not helpful at this stage -insufficient tissue. Exceptions: normal-sized kidneys in CKD (think DM nephropathy, amyloid, ADPKD, HIV nephropathy).
🚨 Management
▶ How to Manage CKD Stage by Stage (tap to expand)
Two parallel tracks at every stage: (1) Slow progression with the Big 4 (BP control, ACEi/ARB, SGLT2i, finerenone if diabetic), (2) Manage complications as nephron loss accumulates (anemia, bone-mineral, acidosis, K+, fluid). KDIGO 2024 added finerenone as a 4th pillar in diabetic CKD with albuminuria and pushed the SGLT2i threshold to eGFR 20.
Step 1: Confirm CKD and stage by GFR + albuminuria
Check
What
Why
Confirm chronicity
Two abnormal values (eGFR < 60 or albuminuria) ≥ 3 months apart
A single abnormal BMP could be AKI, dehydration, or contrast. CKD requires chronicity by definition.
Stage by GFR + UACR
Use the "heat map": G1-G5 × A1-A3. A patient with G2A3 is higher risk than G3aA1.
Both axes independently predict ESKD and CV mortality. Staging by GFR alone undercalls risk.
Identify etiology
BMP, UACR, UA with micro, renal US; pursue further if active sediment, nephrotic proteinuria, rapid decline, young patient, or family hx
~45% DM, ~28% HTN, ~8% GN, ~5% ADPKD. Etiology drives some choices (e.g., tolvaptan for rapid ADPKD, immunosuppression for GN).
Step 2: Universal interventions for every CKD patient
Pillar
How
Why
BP control
Target < 130/80 (< 120/80 if proteinuric per KDIGO 2024)
SPRINT and post-hoc CKD subgroup: intensive control reduces mortality without harming kidney function. BP > 130 accelerates progression and CV death.
ACEi or ARB
Maximally titrated to BP target; required if UACR ≥ 30 (A2 or A3) or proteinuric of any cause
Reduces intraglomerular pressure → slows progression and lowers proteinuria 30-50%. RENAAL, IDNT in diabetic CKD; AASK in hypertensive CKD even in Black patients. Expect Cr rise 10-30%, that's hemodynamic, not injury; only stop if > 30% or K+ > 5.5.
SGLT2 inhibitor
Dapagliflozin 10 mg or empagliflozin 10 mg daily; initiate down to eGFR 20, continue until dialysis
10 mg daily (20 mg if K+ stable and eGFR ≥ 60); ADD to ACEi/ARB + SGLT2i, don't replace
FIDELIO-DKD (2020): 18% reduction in CKD progression. FIGARO-DKD (2021): 13% reduction in CV death/MACE. Non-steroidal MRA, less gynecomastia and less hyperkalemia than spironolactone. Class I in KDIGO 2024 for diabetic CKD.
Lifestyle
Sodium < 2 g/day, protein 0.6-0.8 g/kg/day (Stage 3+), smoking cessation, weight loss
Each independently slows progression. Don't restrict protein below 0.6 g/kg (sarcopenia risk).
CV risk reduction
Statin for all CKD G3-G5 not on dialysis (SHARP); ASA if established ASCVD; A1c < 7% if young, < 8% if frail/elderly
CKD is a CAD risk equivalent. Most CKD patients die of CV disease, not progress to ESKD.
Step 3: Stage-specific add-ons
Stage
What's New This Stage
Why
G1-G2 (eGFR ≥ 60)
Treat etiology, optimize Big 4, reassess every 6-12 months
Most patients are asymptomatic; the window for slowing progression is widest here. Don't wait for symptoms.
EPO production drops at G3a. PTH starts rising. Hep B vaccination needs the higher CKD dosing (double dose) and works best while eGFR is still high.
G3b (30-44)
Nephrology referral if not already; start discussing future kidney replacement options; avoid nephrotoxins; review medication renal dosing
Two-year median to ESKD if eGFR declines > 3 mL/min/yr at this stage. Referral late is the #1 reason patients arrive at ESKD without a transplant or fistula plan.
G4 (15-29)
Kidney replacement therapy education (HD/PD/transplant). Pre-emptive transplant evaluation if eGFR < 20. Vascular surgery referral for AVF/AVG planning at eGFR ~20.
AVF maturation takes 3-6 months; placing it < 6 months before dialysis means starting with a catheter (higher infection/mortality). Pre-emptive transplant has better outcomes than transplant after dialysis start.
G5 (< 15)
Initiate KRT when uremic (not by GFR alone), or palliative pathway if appropriate; complete transplant workup if not done
IDEAL (2010): early-start dialysis offered no benefit over symptom-driven start. Don't initiate by number alone, watch for AEIOU indications.
Step 4: Manage complications as they appear
Complication
Threshold to Act
How
Anemia of CKD
Hb < 10 g/dL
Iron first (target ferritin > 100, TSAT > 20%). Then ESA (epoetin alfa, darbepoetin) targeting Hb 10-11.5 (NOT > 12, increased CV events in TREAT, CHOIR). Consider HIF-PHI (daprodustat) as oral alternative.
CKD-MBD
PO4 > 4.5, PTH > 2-9× upper limit, low 25-OH D
Dietary phosphate restriction → phosphate binders (sevelamer or lanthanum first; avoid Ca-based if vascular calcification). Vit D analogs (calcitriol or cinacalcet) for secondary hyperparathyroidism.
Metabolic acidosis
HCO3 < 22
Sodium bicarbonate 650 mg PO TID, target HCO3 ≥ 22. Slows progression (UBI, 2014). Veverimer if available.
Hyperkalemia
K+ > 5.5 limiting RAAS
Patiromer or SZC to preserve RAAS rather than discontinue it (DIAMOND, AMBER). Diet education, avoid NSAIDs.
Volume overload
Edema, weight gain, dyspnea
Loop diuretic (furosemide, torsemide); often needs higher doses as eGFR falls. Sodium restriction.
Indication to initiate dialysis (AEIOU). Pruritus: gabapentin or difelikefalin (kappa-opioid agonist, FDA-approved 2021).
Step 5: KRT preparation in G4-G5
Modality
When to Choose
Why
Pre-emptive kidney transplant
eGFR < 20, no exclusions; refer to transplant center for evaluation
Best long-term outcomes, lowest mortality. Pre-emptive (before dialysis) is better than post-dialysis. Living donor preferred over deceased.
Hemodialysis (HD)
Patient preference, in-center 3×/wk; home HD for some
Highest "rescue" capability for fluid/K+. AVF preferred over AVG over catheter (infection risk catheter >> graft > fistula).
Peritoneal dialysis (PD)
Patient preference, home-based, daily exchanges or cycler at night
Preserves residual kidney function longer, no vascular access needed, more lifestyle flexibility. Not for patients with prior abdominal surgery/adhesions.
Conservative / palliative
Frail elderly, dementia, multiple comorbidities where dialysis won't extend or improve quality of life
In octogenarians with multiple comorbidities, dialysis often doesn't extend life and worsens QoL. Honest conversations early.
Shortcuts that override the ladder
Scenario
Do This
Why
Cr rise > 30% on ACEi/ARB
Hold RAAS; screen for bilateral renal artery stenosis (renal duplex, MRA)
RAS unmasks itself when ACEi/ARB drops perfusion to the post-stenotic kidney. Don't just reflexively stop and move on.
Hyperkalemia on RAAS or finerenone
Try patiromer or SZC first; only stop the renoprotective drug if binders fail
RAAS-blockade and finerenone slow progression. Mortality and ESKD benefit is lost if discontinued. K+ binders preserve the regimen.
ADPKD with rapid progression (eGFR drop > 3 mL/min/yr or significant TKV growth)
Tolvaptan (Jynarque); requires LFT monitoring
TEMPO 3:4 (2012) and REPRISE (2017): tolvaptan slowed eGFR decline and total kidney volume growth. Only disease-modifier in ADPKD.
Diabetic CKD with persistent albuminuria on ACEi+SGLT2i
Add finerenone (titrate based on K+ and eGFR)
FIDELIO-DKD/FIGARO-DKD: additive benefit on top of RAAS+SGLT2i. The 4th pillar for diabetic CKD.
Iodinated contrast in eGFR 30-44
Pre/post hydration (isotonic saline 1-1.5 mL/kg/hr); hold metformin and SGLT2i 48 hr; don't withhold contrast if clinically necessary
Contrast-associated AKI risk in modern era is modest; outdated reflexes to avoid contrast can delay diagnosis. PRESERVE (2018): NAC and bicarb didn't help; isotonic saline is what works.
Pregnancy + CKD
Switch ACEi/ARB to labetalol, nifedipine, or methyldopa; close OB-nephro co-management
ACEi/ARB are teratogenic (renal dysgenesis, oligohydramnios). SGLT2i and finerenone also avoided. Pregnancy itself can accelerate CKD; risk stratify by pre-pregnancy eGFR.
Hold "DRAMA" sick-day meds: Diuretics, RAAS, ARBs/ARNI, Metformin, Anti-inflammatories (NSAIDs); also hold SGLT2i
Volume contraction + these drugs = AKI. Resume once eating/drinking and Cr stable.
AKI on top of CKD
Look for reversible cause (volume, obstruction, nephrotoxin, contrast, infection) before assuming progression
~30% of "CKD progression" is actually superimposed AKI that recovers. Treat the AKI; reassess baseline in 3 months.
Refractory albuminuria despite max ACEi+SGLT2i+finerenone
Confirm adherence; refer for biopsy (GN missed at diagnosis); consider GLP-1 RA (FLOW trial, semaglutide reduced kidney events 24%)
FLOW (2024): semaglutide in diabetic CKD reduced major kidney + CV events 24%. New addition to the toolbox. Biopsy uncovers treatable GN (IgA, FSGS, lupus) in some "diabetic CKD" patients.
"Bad-looking" eGFR in muscular or amputee patient
Use cystatin C-based eGFR (eGFRcr-cys is more accurate)
Creatinine is muscle-mass dependent; low muscle (amputee, elderly, sarcopenia) overestimates eGFR. Cystatin C is muscle-independent. 2021 CKD-EPI race-free equation also recommended.
Cornerstone Therapies -Slow Progression
The "Big 4" that change CKD trajectory: BP control, ACEi/ARB, SGLT2 inhibitor, finerenone (if diabetic CKD). Every CKD patient with albuminuria should be on the first three.
1. BP Control
Target < 120/80 mmHg if proteinuria present SPRINT, 2015. Target < 130/80 for all CKD KDIGO, 2024. First-line: ACEi or ARB (dual RAAS blockade).
2. ACEi / ARB
Foundational therapy if albuminuria (A2 or A3). Reduces intraglomerular pressure, slows progression, reduces proteinuria 30–50%. RENAAL, 2001: losartan reduced ESKD by 28% in diabetic nephropathy. IDNT, 2001: irbesartan similar benefit. Do NOT combine ACEi + ARB ONTARGET, 2008: no additional benefit, increased hyperkalemia + AKI.
Expect Cr to rise 10–30% after initiation -this is acceptable and expected. Only hold if Cr rises > 30% or K⁺ > 5.5.
3. SGLT2 Inhibitor
Add to ACEi/ARB in all CKD with eGFR ≥ 20 and albuminuria. Benefit is independent of diabetes status. DAPA-CKD, 2020: dapagliflozin reduced CKD progression by 39%. Trial stopped early for efficacy. Benefit in both diabetic and non-diabetic CKD. EMPA-KIDNEY, 2022: empagliflozin reduced progression by 28%. Benefit down to eGFR 20.
Mechanism: restores tubuloglomerular feedback → constricts afferent arteriole → reduces intraglomerular pressure. Also natriuretic, reduces weight, lowers BP. Expect initial eGFR dip of 3–5 mL/min (like ACEi) -this is hemodynamic, not injury. Do not stop.
4. Finerenone (Kerendia)
Add in diabetic CKD with persistent albuminuria despite ACEi/ARB + SGLT2i. FIDELIO-DKD, 2020: 18% reduction in kidney composite endpoint. FIGARO-DKD, 2021: 13% reduction in CV composite.
Non-steroidal MRA -less hyperkalemia than spironolactone. Requires K⁺ < 5.0 and eGFR ≥ 25 to initiate. Monitor K⁺ within 4 weeks.
Lifestyle & Supportive
Dietary sodium restriction -< 2g/day. Enhances efficacy of RAAS blockade and reduces edema/HTN.
Protein intake -0.8 g/kg/day in G3–G5 (not on dialysis). Excessive protein accelerates hyperfiltration.
Glycemic control (DM) -HbA1c < 7% (individualize in elderly/frail). SGLT2i counts toward this.
Smoking cessation -smoking accelerates CKD progression and CV risk.
Statin therapy -CKD is a coronary risk equivalent. Statin for all G3–G5 not on dialysis SHARP, 2011: simvastatin/ezetimibe reduced major atherosclerotic events by 17%.
Avoid nephrotoxins -NSAIDs, aminoglycosides, IV contrast (pre-hydrate if essential), herbal supplements.
Vaccinations -Hepatitis B (double dose: 40 mcg), influenza annually, pneumococcal (PCV20 or PCV15 + PPSV23), COVID-19.
⚠️ Complications
CKD-Mineral Bone Disease (CKD-MBD)
Begins at G3. The kidneys fail to excrete phosphate and activate vitamin D → hyperphosphatemia → hypocalcemia → secondary hyperparathyroidism → renal osteodystrophy → vascular calcification → cardiovascular death.
Uremic platelet dysfunction -prolonged bleeding time despite normal PT/INR. Treat with desmopressin (DDAVP) 0.3 mcg/kg IV for acute procedures. Conjugated estrogens for sustained effect.
💊 Medications
CKD-Specific Medications
Drug (Brand)
Class
Dose
Indication
Key Points
Dapagliflozin (Farxiga) 1ST LINE
SGLT2i
10 mg PO daily
CKD with eGFR ≥ 20 + albuminuria
DAPA-CKD, 2020. DM and non-DM. Do not initiate < 20.
Empagliflozin (Jardiance) 1ST LINE
SGLT2i
10 mg PO daily
CKD with eGFR ≥ 20
EMPA-KIDNEY, 2022. Benefits down to eGFR 20.
Finerenone (Kerendia) ADD-ON
Non-steroidal MRA
10–20 mg PO daily
Diabetic CKD with albuminuria despite ACEi/ARB
FIDELIO-DKD, 2020. Requires K⁺ < 5.0 to start. Monitor K⁺ at 4 wks.
Sevelamer (Renvela) PREFERRED
Phosphate binder
800–1600 mg with meals
Hyperphosphatemia (G4–G5)
Non-calcium binder. Preferred over calcium-based binders to avoid vascular calcification.
Calcitriol (Rocaltrol)
Active vitamin D
0.25–0.5 mcg PO daily
Secondary hyperparathyroidism
Monitor Ca²⁺ (risk of hypercalcemia). Alternative: paricalcitol (Zemplar) -less hypercalcemia.
Cinacalcet (Sensipar)
Calcimimetic
30–180 mg PO daily
Secondary hyperPTH on dialysis
Activates CaSR on parathyroid → suppresses PTH. GI side effects common.
Epoetin alfa (Epogen) AFTER IRON
ESA
50–300 units/kg 3×/week IV/SC
Anemia of CKD (Hgb < 10)
Iron-replete first. Target Hgb 10–11.5. Never > 13 TREAT, 2009.
Darbepoetin (Aranesp)
ESA (long-acting)
0.45 mcg/kg q2 weeks or monthly
Anemia of CKD
Less frequent dosing than epoetin. Same Hgb target.
Sodium bicarbonate
Alkali
650–1300 mg PO TID
Metabolic acidosis (bicarb < 22)
Slows CKD progression. Watch for volume overload (Na⁺ content).
Patiromer (Veltassa) ADJUNCT
K⁺ binder
8.4–25.2 g PO daily
Chronic hyperkalemia on RAAS blockade
Allows continuation of ACEi/ARB/MRA. Takes hours to work -not for acute hyperK.
Drug Dosing in Renal Impairment
Renal impairment changes a drug in one of three ways: it becomes unsafe (stop or avoid), it accumulates (reduce the dose or extend the interval), or it needs level-guided dosing. Most drug labels use Cockcroft-Gault creatinine clearance (CrCl calculator), not eGFR, the two diverge at extremes of body size, so dose by CrCl and stage by eGFR. In AKI, kidney function is a moving target, assume the worst, dose conservatively, and recheck daily. Thresholds below are starting points, confirm against the current label for any unfamiliar drug.
Amiodarone (hepatic clearance) for rhythm; metoprolol or diltiazem for rate control.
Gadolinium (group I agents)
Avoid eGFR < 30 and dialysis
Nephrogenic systemic fibrosis.
Newer group II gadolinium agent (NSF risk near zero), lowest dose; or non-contrast MRI.
2. Antibiotics (adjust or monitor)
Drug
What to do
Why
Use instead
Vancomycin
Dose by AUC/levels, extend the interval as CrCl falls
Renally cleared and itself nephrotoxic. Trough/AUC-guided dosing prevents both under-treatment and AKI.
If AKI or level problems: linezolid or daptomycin for MRSA (no renal efficacy penalty; daptomycin interval extended).
Aminoglycosides (gentamicin, tobramycin)
Extend interval, monitor troughs, avoid if an alternative exists
Nephrotoxic (ATN) and ototoxic; toxicity rises with accumulation.
An anti-pseudomonal beta-lactam (cefepime, pip-tazo, meropenem, all dose-adjusted) per susceptibility.
Cefepime
Reduce dose per CrCl
Neurotoxicity (encephalopathy, myoclonus, nonconvulsive status epilepticus); ~85% of cases occur in renal impairment without dose adjustment.
Dose-adjust rather than swap; if neurotoxicity occurs, switch to meropenem or pip-tazo (also adjusted).
Piperacillin-tazobactam
Reduce per CrCl
Observational data long suggested additive AKI when paired with vancomycin, but the only randomized trial ACORN, 2023 found no difference in its primary AKI/death endpoint. Do not withhold pip-tazo on renal grounds alone.
Use AUC-guided vancomycin and monitor renal function either way. If you do prefer cefepime, prefer it for anaerobic sparing, and remember cefepime neurotoxicity accumulates in CKD.
Carbapenems (meropenem, imipenem)
Reduce per CrCl
Accumulation lowers the seizure threshold (imipenem most). Also lowers valproate levels.
Meropenem over imipenem (lower seizure risk); dose-adjust rather than swap class if carbapenem is indicated.
Moxifloxacin (no renal adjustment, hepatic) where the spectrum fits; otherwise a beta-lactam per organism.
TMP-SMX
Reduce dose CrCl < 30
Trimethoprim blocks ENaC (hyperkalemia) and tubular creatinine secretion (a pseudo-rise in Cr, not true AKI). Distinguish before stopping.
Indication-dependent (no universal swap); for UTI use cephalexin, for PJP the dose is reduced rather than substituted.
Acyclovir / valacyclovir
Reduce per CrCl, hydrate, infuse IV slowly
Crystal nephropathy and neurotoxicity (confusion, myoclonus) when not adjusted.
Dose-adjust and hydrate rather than swap; valacyclovir PO over IV acyclovir when oral therapy is appropriate.
3. Anticoagulants
Listed preferred-first. Apixaban is the DOAC of choice in CKD because it is the least renally cleared (~27%); rivaroxaban follows directly to make the contrast obvious (~36% renal, so it is dose-reduced earlier and avoided sooner). Dabigatran is the most kidney-dependent and the first to drop off.
Drug
Threshold / action
Why
Use instead
ApixabanPREFERRED DOAC
Reduce to 2.5 mg BID if 2 of 3: age ≥ 80, weight ≤ 60 kg, Cr ≥ 1.5
Least renally cleared DOAC (~27%), most usable in advanced CKD. Use in dialysis remains debated but it is the DOAC of choice when one is used.
This is the preferred alternative; if a DOAC is unsuitable, warfarin (INR-titrated) remains usable at any GFR.
Rivaroxaban
AFib CrCl 15–50 → 15 mg daily; avoid < 15
More renally cleared than apixaban (~36%), so it accumulates sooner → bleeding. Same Xa-inhibitor class, but apixaban is preferred as function falls.
~80% renal clearance, the most kidney-dependent DOAC, so bleeding climbs fastest as function falls.
Apixaban (or warfarin) below CrCl 30.
Edoxaban
Reduce if CrCl 15–50; avoid if CrCl > 95 or < 15
The > 95 paradox: it under-protects against stroke at high clearance, a classic exam point.
Apixaban or rivaroxaban if CrCl > 95; apixaban/warfarin if < 15.
Enoxaparin
Treatment dose 1 mg/kg once daily (not BID) if CrCl < 30; consider anti-Xa monitoring
Renal accumulation → bleeding.
IV unfractionated heparin (titratable, reversible, not renally cleared) in severe renal failure.
4. Diabetes agents
Drug
Threshold / action
Why
Use instead
SGLT2 inhibitors (dapa/empa)
Initiate eGFR ≥ 20 (empagliflozin) or ≥ 25 (dapagliflozin); continue until dialysis
Glucose-lowering fades below ~45, but renal and CV protection persists, so keep them on for the kidney benefit, not the sugar.
Below the initiation threshold, add a GLP-1 RA or linagliptin for glycemic control.
Sulfonylureas
Prefer glipizide; avoid glyburide
Glipizide is hepatically metabolized; glyburide has renally cleared active metabolites causing prolonged hypoglycemia.
Glipizide; or shift to an SGLT2i, GLP-1 RA, or linagliptin.
Insulin
Reduce total daily dose as eGFR falls
The kidney clears insulin; less clearance means longer action and more hypoglycemia.
Same agent, lower dose; favor titratable basal-bolus over fixed mixes for safety.
DPP-4 inhibitors
Reduce sitagliptin/saxagliptin; linagliptin needs no adjustment
Linagliptin is biliary/hepatically cleared, the go-to gliptin in CKD.
Linagliptin (no renal dose adjustment).
GLP-1 agonists
Generally no dose change
Watch for volume depletion from GI losses (nausea, vomiting), which can precipitate prerenal AKI.
No swap needed; hydrate and titrate slowly. A preferred class in CKD.
5. Cardiovascular
Drug
What to do
Why
Use instead
Digoxin
Reduce dose, monitor levels
Narrow therapeutic index and renally cleared; toxicity is worsened by the hypokalemia and hypomagnesemia common in CKD.
For rate control, a beta-blocker or non-DHP calcium channel blocker instead.
Atenolol, nadolol, sotalol
Accumulate as CrCl falls
Renally cleared beta-blockers build up (bradycardia, heart block); the hepatically cleared ones are safer in CKD.
Metoprolol or carvedilol (hepatic clearance, no renal adjustment).
ACEi / ARB
Not dose-reduced, but expect a Cr rise ≤ 30% (acceptable) and watch K⁺; hold during AKI or acute illness (sick-day rule)
Efferent arteriolar dilation drops GFR slightly; only a Cr rise > 30% or hyperkalemia signals true harm. They remain renoprotective long-term.
No swap, they are renoprotective; if intolerant from hyperkalemia, add a K⁺ binder (patiromer) rather than stopping.
Rosuvastatin
Max 10 mg/day if eGFR < 30
Higher systemic exposure in renal impairment raises myopathy/rhabdomyolysis risk.
Atorvastatin (hepatic/biliary clearance, no renal dose cap).
6. Analgesia, neuro, and miscellaneous
Drug
What to do
Why
Use instead
Gabapentin / pregabalin
Reduce ~50% if CrCl < 60; CKD4 (15–29) ~200–700 mg/day; CKD5 or HD 100–300 mg with a dose after dialysis
> 90% renal elimination, accumulation causes sedation, myoclonus, and falls, a very common inpatient error.
Reduce dose rather than swap; for neuropathic pain a tricyclic (nortriptyline) or duloxetine avoids renal accumulation.
Morphine, codeine
Avoid in advanced CKD
The active metabolite morphine-6-glucuronide is renally cleared and accumulates → sedation and respiratory depression.
Hydromorphone or fentanyl (fentanyl is the safest opioid in renal failure).
Tramadol
Reduce dose
Metabolite accumulation plus a lowered seizure threshold.
Fentanyl or low-dose hydromorphone for opioid-requiring pain.
Allopurinol
Start low (50–100 mg), titrate to the urate target with monitoring
The active metabolite oxypurinol accumulates and can trigger allopurinol hypersensitivity syndrome (DRESS, SJS/TEN). Slow titration, not a fixed low cap, is current practice.
Febuxostat (hepatic metabolism, no renal dose adjustment); note the CARES CV-mortality signal, weigh in cardiac patients.
Colchicine
Reduce or avoid; never combine with a strong CYP3A4/P-gp inhibitor in renal failure
Accumulation → myoneuropathy and marrow suppression.
For acute gout, corticosteroids (oral or intra-articular); IL-1 inhibitor if refractory.
Symptomatic uremia (nausea, anorexia, asterixis, neuropathy) -typically GFR 5–10
Do NOT start dialysis based on GFR alone.IDEAL, 2010: early dialysis initiation (GFR 10–14) vs late (GFR 5–7) showed no survival benefit. Start for symptoms or complications, not a number.
Dialysis Modalities
Modality
Access
Schedule
Best For
Disadvantages
Hemodialysis (HD)
AV fistula (best) > AV graft > tunneled catheter (worst)
ICU-only, resource intensive, requires anticoagulation of circuit.
Access Planning
AV fistula referral at eGFR ~20 (G4) -needs 2–3 months to mature before use. "Fistula first" approach.
Protect the non-dominant arm -no blood draws, no IVs, no BP cuffs on the future fistula arm from G4 onwards.
Avoid subclavian lines -causes subclavian stenosis, makes future fistula/graft on that side impossible. Use IJ if central access needed.
Transplant evaluation -refer when GFR < 20. Pre-emptive transplant (before dialysis) has best outcomes. Living donor preferred.
BP target in ESRD: SBP, not MAP
For chronic dialysis BP management, follow SBP, not MAP. Vascular calcification widens pulse pressure in dialysis patients, so a "normal" MAP can hide a damaging SBP. Example: BP 180/60 gives MAP 100 (looks fine) but that 180 SBP is hammering the brain and heart every beat. KDOQI and KDIGO target SBP. Caveat: in acute settings (intra-dialytic crash, sepsis, peri-op), MAP still rules for organ perfusion.
📋 On Rounds
Pimp Questions
Why should you never combine ACEi + ARB in CKD?
ONTARGET, 2008: dual RAAS blockade (ramipril + telmisartan) vs either alone -no additional renal benefit, but significantly more hyperkalemia, hypotension, and acute kidney injury. Also: VA NEPHRON-D, 2013 stopped early for safety (losartan + lisinopril in diabetic nephropathy). Bottom line: one RAAS blocker is enough. If more antiproteinuric effect needed, add SGLT2i or finerenone.
Why does eGFR dip when you start an SGLT2 inhibitor?
SGLT2 inhibitors restore tubuloglomerular feedback -they increase sodium delivery to the macula densa, which signals afferent arteriolar constriction, reducing intraglomerular pressure. This is the therapeutic mechanism (same concept as ACEi reducing efferent tone). The initial eGFR dip of 3–5 mL/min reflects reduced hyperfiltration, not kidney injury. It stabilizes within weeks and long-term GFR slope is markedly better.
Why is HbA1c unreliable in ESKD?
Two reasons: (1) EPO/ESA therapy → increased reticulocyte production → younger RBCs → shorter glycation time → falsely LOW HbA1c. (2) Uremia → carbamylated hemoglobin → can interfere with some assays → falsely HIGH. Also, shortened RBC lifespan in ESKD (90 vs 120 days) → less glycation time. Alternative: use glycated albumin or fructosamine for glycemic monitoring in ESKD.
When should you refer for AV fistula creation?
At eGFR ~20 (CKD G4), or ~12 months before anticipated dialysis start. AV fistulas need 2–3 months to mature (some need 6 months). "Fistula first" -AVF has lowest infection rate, best long-term patency, and lowest mortality compared to grafts or catheters. Protect the non-dominant arm from G4 onwards (no IVs, no blood draws, no BP cuffs). Avoid subclavian central lines -causes stenosis that ruins ipsilateral fistula options.
Should you start dialysis early based on GFR alone?
No. IDEAL, 2010: randomized early start (eGFR 10–14) vs late start (eGFR 5–7) in 828 patients -no difference in mortality, CV events, infections, or quality of life. Early start just means more time on dialysis with no survival benefit. Start dialysis for symptoms (uremia, refractory volume overload, refractory hyperK, pericarditis) -not a number.
Clinical Examples
Case 1: CKD Stage 3b with Albuminuria
Presentation: 62M with T2DM and HTN. eGFR 38, UACR 450 mg/g, BP 134/82. Currently on Lisinopril (Prinivil) 40 mg daily.
Key Decisions:
Add Dapagliflozin (Farxiga) 10 mg daily, DAPA-CKD, 2020 showed 39% reduction in CKD progression regardless of diabetes status
Add Finerenone (Kerendia) 10–20 mg daily, FIDELIO-DKD, 2020 reduced CKD progression and CV events in diabetic kidney disease
Expect initial eGFR dip of 3–5 mL/min after starting SGLT2i, this is the therapeutic mechanism (tubuloglomerular feedback), not injury. Continue if dip < 30% and stable.
Monitor potassium at 2–4 weeks after starting finerenone (hold if K⁺ > 5.5 at initiation)
Nephrology referral now, eGFR < 30 threshold approaching; early referral allows time for fistula planning if trajectory continues
Teaching point: SGLT2i + finerenone + ACEi/ARB triple combination is now guideline-supported for CKD with albuminuria and DM. Do NOT add ARB on top of ACEi (ONTARGET).
Anemia (Hgb 9.2): Check iron studies first, replete iron (IV iron preferred if TSAT < 20%). If iron-replete, start Epoetin Alfa (Epogen) or Darbepoetin (Aranesp); target Hgb 10–11
Hyperkalemia (K⁺ 5.6): Dietary potassium restriction + consider Patiromer (Veltassa) to allow continuation of RAAS blockade
Secondary hyperPTH (PTH 310, PO₄ 5.4): Start phosphorus binder (e.g., Sevelamer (Renvela) 800 mg TID with meals)
AV fistula referral, eGFR 18 means dialysis likely within 1–2 years; fistula needs 3–6 months to mature
Modality discussion: Address HD vs PD vs transplant. Transplant eval at eGFR ~20. PD preferred if preserved residual function and self-care capable.
Teaching point: CKD G4 is a system, address all complications simultaneously. Do not defer anemia, acidosis, or MBD management while waiting for dialysis.
Case 3: Acute-on-Chronic Kidney Injury
Presentation: 55M with baseline CKD G3 (Cr 1.8). Admitted with Cr 4.2 after 5 days of ibuprofen for back pain + nausea/vomiting with poor PO intake.
Immediate Management:
Hold nephrotoxins immediately: Stop all NSAIDs, hold ACEi/ARB, hold metformin (if applicable)
IV fluids cautiously: NS or LR at 100–150 mL/hr to restore euvolemia, reassess frequently; avoid volume overload in underlying CKD
Monitor closely: Daily BMP (K⁺, bicarb, Cr), urine output. Watch for hyperkalemia and need for emergent dialysis (AEIOU criteria)
Trend creatinine: If Cr begins to fall within 48–72 hrs → AKI superimposed on CKD. If plateau or worsening → consider intrinsic AKI (NSAID-induced AIN) vs true CKD progression
Renal recovery window: Do NOT restart ACEi/ARB until Cr returns to within 25% of baseline and patient euvolemic
Distinguish AKI from CKD progression: True CKD progression requires eGFR decline > 5 mL/min/yr over ≥ 3 months, a single elevated Cr in an ill patient is not CKD progression
Teaching point: NSAIDs reduce prostaglandin-mediated afferent arteriolar dilation, in CKD, this causes acute hemodynamic AKI. This is the #1 avoidable AKI cause in CKD patients. Counsel all CKD patients to avoid NSAIDs absolutely.
Sample Presentation
📋 CKD -Outpatient Nephrology
"Mr. Patel is a 58-year-old man with Type 2 DM, HTN, and CKD Stage G3b-A3 (eGFR 38, UACR 820 mg/g). He is on lisinopril 40 mg daily, dapagliflozin 10 mg daily, and was recently started on finerenone 10 mg daily -K⁺ was 4.6 at 4-week check. His BP today is 128/76. Labs show Hgb 10.8, bicarb 21, Ca 8.9, PO₄ 4.8, PTH 128, 25-OH Vitamin D 18. Plan: start sodium bicarb 650 mg TID for acidosis, replete Vitamin D with ergocalciferol 50,000 units weekly × 8 weeks, recheck PTH/Ca/PO₄ in 3 months. AV fistula referral placed. Transplant evaluation in progress."
Hgb trending -anemia of CKD begins at G3. If Hgb < 10 → check iron studies → replete iron → then ESA if needed.
Iron studies (ferritin, TSAT)
q3–6 months
Ferritin > 100 (or > 200 on dialysis), TSAT > 20%. Iron-replete before starting ESA.
HbA1c (if diabetic)
q3 months
Target < 7% (individualize). Note: HbA1c unreliable in ESKD (shortened RBC lifespan, EPO use) -use fructosamine or CGM.
BP
Every visit + home monitoring
Target < 130/80 (KDIGO 2024). < 120/80 if tolerated with proteinuria SPRINT, 2015.
Lipids
Annually
CKD is a coronary risk equivalent. Statin for all G3–G5 not on dialysis.
Urinalysis
Annually
Monitor for active sediment (new hematuria, worsening proteinuria).
Hepatitis B/C screening
At diagnosis, then periodically
All CKD patients. Hep B vaccination if non-immune (double dose: 40 mcg).
Bone density (DEXA)
Consider in G3–G5 with fracture risk
CKD-MBD causes renal osteodystrophy. DEXA interpretation is complex in CKD -discuss with nephrology.
CKD monitoring is a system. Every visit: BP, eGFR trend, UACR, K+, bicarb. Every 3–6 months: CBC, iron, Ca/PO4/PTH. Annually: lipids, HbA1c, UA, Hep B/C. Adjust medications based on trends, not single values.
G1 to G5 by eGFR, A1 to A3 by urine albumin-to-creatinine ratio.Albuminuria is an independent predictor of progression and cardiovascular death, so staging on eGFR alone understates risk: a patient with a normal eGFR and an ACR above 300 is high risk. CKD requires abnormality persisting beyond 3 months, which is what separates it from AKI.
Four Interventions Slow Progression
RAAS blockade (ACE inhibitor or ARB) titrated to the maximum tolerated dose, an SGLT2 inhibitor, blood pressure control to a systolic below 120 where tolerated, and glycemic control in diabetes.SGLT2 inhibitors slow progression and reduce cardiovascular events regardless of diabetes status (DAPA-CKD, EMPA-KIDNEY), and they are now a cornerstone rather than a diabetes drug.
Expect and Tolerate the Creatinine Bump
A rise of up to about 30% after starting an ACE inhibitor, ARB or SGLT2 inhibitor is expected and reflects the intended hemodynamic effect.Do not stop the drug for it.Investigate a rise beyond 30%, which suggests volume depletion or bilateral renal artery stenosis. Recheck creatinine and potassium 1 to 2 weeks after any change.
Add Finerenone in Diabetic Kidney Disease
A non-steroidal MRA that reduces progression and cardiovascular events on top of RAAS blockade and an SGLT2 inhibitor (FIDELIO-DKD, FIGARO-DKD). Monitor potassium closely, since the combination of three agents that all raise it is where hyperkalemia becomes the limiting factor.
Treat the Complications as They Appear
Anemia: correct iron first, then an ESA targeting hemoglobin 10 to 11 g/dL, because higher targets increase stroke and thrombosis. Metabolic acidosis: bicarbonate to keep it above 22, which itself slows progression and preserves muscle. CKD-MBD: control phosphate with dietary restriction and binders, then vitamin D and a calcimimetic for hyperparathyroidism. Hyperkalemia: diet, diuretics and a potassium binder, so that the RAAS blocker can be continued.
Do Not Chase Every Number
Do not correct anemia to normal, do not normalize PTH, and do not treat mild asymptomatic hyperphosphatemia aggressively. Each of those instincts has been tested and each caused harm or no benefit. The targets in CKD are deliberately loose, and treating to a normal value is the commonest source of iatrogenic harm on this page.
Protect the Kidneys That Are Left
Avoid NSAIDs entirely, renally dose every drug, minimize contrast where a real alternative exists, and hold nephrotoxins during acute illness.Give sick-day guidance: hold the ACE inhibitor or ARB, the SGLT2 inhibitor, diuretics and metformin during vomiting, diarrhea or dehydration, since an AKI on CKD is what causes stepwise permanent loss.
Prepare for Replacement Before You Need It
Refer to nephrology at eGFR below 30, and start access planning at G4: a fistula needs months to mature, so a late referral means a catheter and its infection risk. Discuss hemodialysis, peritoneal dialysis, transplant and conservative management, and preserve the non-dominant arm veins by avoiding PICCs and unnecessary phlebotomy. Start dialysis for symptoms and complications, not for a number, since early initiation by eGFR alone does not improve outcomes (IDEAL).
Legacy 2013 Pooled Cohort Equation (ACC/AHA 2013/2018). Retired by the 2026 ACC/AHA Dyslipidemia Guideline -use the PREVENT calculator above for current 2026 guidance. PCE retained here for cross-reference and patients still being managed on prior thresholds. Validated for ages 40-79 without prior CV event, stroke, or PAD. Inputs: age, sex, race, total cholesterol, HDL, SBP, treated HTN status, DM, smoking. Tends to overestimate risk vs PREVENT, especially in Black patients and the elderly.
Wells Score (PE)
Pretest probability of pulmonary embolism.
PERC Rule (PE Rule-Out Criteria)
Use ONLY if pre-test probability is already LOW (gestalt < 15%). All 8 criteria must be negative to rule out PE without a D-dimer.
sPESI (Simplified PE Severity Index)
30-day mortality risk in acute PE. Identifies outpatient-eligible patients (score 0) vs those needing admission (score ≥ 1).
Hestia Criteria (Outpatient PE Eligibility)
11 exclusion criteria for home treatment of acute PE. Any single YES = not an outpatient candidate.
MAP (Mean Arterial Pressure)
Estimates average arterial pressure during one cardiac cycle
QTc (Corrected QT Interval)
Bazett formula -corrects QT interval for heart rate
Pulmonology
CURB-65 (Pneumonia)
Severity scoring for community-acquired pneumonia. Guides disposition.
Modified Medical Research Council Dyspnea Scale. Quantifies functional impairment from breathlessness. Drives the symptom axis of COPD ABE classification (mMRC ≥ 2 = high symptoms → Group B or E).
CAT (COPD Assessment Test)
8-item symptom questionnaire. Each item scored 0-5; total 0-40. CAT ≥ 10 = high symptom burden (Group B or E in COPD ABE classification). Used alongside mMRC.
STOP-BANG (OSA Screening)
Pre-test probability of obstructive sleep apnea. 8 yes/no items, 1 point each. Validated for pre-op screening and high-yield in resistant HTN (OSA is the #1 secondary cause). Score ≥ 3 = at risk for OSA; ≥ 5 = high probability of MODERATE-TO-SEVERE OSA.
ICU / Critical Care
Glasgow Coma Scale (GCS)
Quantify consciousness. Range 3–15. GCS ≤ 8 = intubate for airway protection.
NEWS Score
National Early Warning Score -SSC 2026 recommended sepsis screening tool. Scores 7 parameters.
MEWS Score
Modified Early Warning Score -simpler alternative to NEWS. Score ≥5 = urgent clinical review.
Neurology
NIHSS (NIH Stroke Scale)
11-item stroke severity scale. Drives thrombectomy eligibility (≥ 6), antiplatelet choice (≤ 3 → DAPT per CHANCE/POINT), and prognosis. Score before tPA, after tPA, and daily.
Convert between opioids using total daily OME. Always reduce calculated equivalent by 25–50% for incomplete cross-tolerance when rotating. Methadone is NOT linear, consult palliative care.
GI / Hepatology
MELD-Na
Model for End-Stage Liver Disease. Transplant priority and 3-month mortality.
General
BMI (Body Mass Index)
Weight-based classification for nutritional status
Steroid Converter
Glucocorticoid equivalence -converts between common steroids
EmergentNeuro · ICU
Glasgow Coma Scale -Pocket Card
Print this and tape it to your badge. GCS ≤ 8 = intubate. Motor is the most prognostically important component.
Component
Response
Score
Eye Opening (E)
Spontaneous
4
To voice / command
3
To pressure / pain
2
None
1
Verbal Response (V)
Oriented (person, place, time, event)
5
Confused (converses but disoriented)
4
Inappropriate words (random words, no conversation)
3
Incomprehensible sounds (moaning, no words)
2
None
1
Motor Response (M) Most prognostically important
Obeys commands
6
Localizes pain (reaches toward stimulus)
5
Normal flexion / withdrawal (pulls away)
4
Abnormal flexion / decorticate (arms flex, legs extend)
3
Extension / decerebrate (arms and legs extend)
2
None
1
Severity Classification
GCS Score
Severity
Action
13 – 15
Mild
Observation, serial neuro exams q1–2h. CT head if: anticoagulation, focal deficit, LOC, persistent vomiting, age > 65, coagulopathy.
INTUBATE for airway protection. CT head STAT. ICU. Neurosurgery consult. Consider ICP monitoring if TBI (bolt if GCS ≤ 8 + abnormal CT).
3
Minimum (coma)
Worst possible score. No eye opening, no verbal, no motor. Evaluate for brain death criteria if persistent.
Clinical Pearls
GCS ≤ 8 = intubate. The patient cannot protect their own airway. This is the single most important GCS threshold.
Motor score is the most prognostically important component. A patient with E1V1M5 (GCS 7) has a much better prognosis than E2V2M3 (GCS 7) -same total, very different meaning.
Always report components, not just the total: "GCS 8 (E2V2M4)" -not just "GCS 8." The components tell you where the deficit is.
Intubated patients: Verbal = 1T (denotes tube). Report as "GCS 7T (E2V1TM4)." Cannot assess verbal in intubated patients.
GCS was validated for TBI -it is less reliable in metabolic coma, drug overdose, or non-traumatic causes. Use alongside pupil reactivity for better prognostication (GCS-Pupils score).
"GCS is 15 -eyes open spontaneously, oriented and conversing, following commands."
Confused patient
"GCS is 13, that's E4 V4 M5 -eyes open spontaneously, conversing but confused to date and place, localizes to pain."
Obtunded patient
"GCS is 9, E2 V3 M4 -eyes open to pain only, inappropriate words, withdraws from pain. This is down from 12 yesterday -we need a stat CT head."
Intubated patient
"GCS is 7T -that's E2 V1T M4. Eyes open to pain, intubated so verbal is untestable, withdraws to pain. Sedation is off for over 2 hours."
Comatose patient
"GCS is 3, E1 V1 M1 -no eye opening, no verbal, no motor response to central pain. Pupils are 4 mm and fixed bilaterally. We need to discuss brain death evaluation."
Improving patient
"GCS improved from 8 to 11 overnight -now E3 V3 M5. Eyes opening to voice, still using inappropriate words, but now localizing to pain. Motor improvement is the most important prognostic sign here."
The formula for presenting GCS: "GCS is [total], that's E[_] V[_] M[_] -[describe what each means in plain English]." Always state the trend compared to prior ("up from…" / "down from…" / "unchanged from…"). If intubated, say "V1T" and note how long sedation has been off. If there are confounders (sedation, paralysis, orbital swelling), state them: "GCS is limited by ongoing propofol -motor is the only reliable component."
How to Test
Component
How to Assess
Eye
Observe → if no spontaneous opening, call patient's name loudly → if no response, apply central pain (trapezius squeeze or sternal rub). Do NOT use peripheral pain for eye opening (may cause withdrawal without eye opening).
Verbal
Ask: "What is your name? Where are you? What month/year is it? What happened?" Oriented = all 4 correct. Confused = conversing but wrong answers. Inappropriate = single words, no conversation. Incomprehensible = moans/groans only.
Motor
Ask patient to "show me two fingers" or "lift your arms." If no response → apply central pain (trapezius squeeze preferred over sternal rub -less tissue damage). Observe best response in any limb. Localizes = hand crosses midline and reaches above clavicle toward stimulus. Flexion = arm bends at elbow. Extension = arm straightens and internally rotates.
Decorticate (flexion, GCS M3) vs Decerebrate (extension, GCS M2): Decorticate = cortical damage above red nucleus → arms flex, legs extend. Decerebrate = brainstem damage below red nucleus → all limbs extend. Decerebrate carries a worse prognosis. Mnemonic: de-COR-ticate = CORtex = arms toward CORE (flex). de-CERE-brate = CEREbellum level = arms extend.
EMERGENTICUVentilator
ARDS -Acute Respiratory Distress Syndrome
Diffuse inflammatory lung injury causing refractory hypoxemia. The cornerstone of management is lung-protective ventilation -low tidal volumes, prone positioning, and avoiding further barotrauma.
🔍 Overview
Definition
ARDS is acute, diffuse inflammatory lung injury causing increased alveolar-capillary permeability, pulmonary edema, and severe hypoxemia not explained by cardiac failure. Definition uses the Berlin Definition of ARDS (2012).
Bilateral opacities on CXR/CT (not explained by effusion/collapse)
Origin of edema
Not fully explained by heart failure or fluid overload
Oxygenation (P/F)
Used to grade severity (see below), with PEEP ≥ 5 cmH₂O
ARDS Severity Classification
Severity
PaO₂/FiO₂ (P/F Ratio)
Mortality
Mild
200–300 mmHg
~27%
Moderate
100–200 mmHg
~32%
Severe
< 100 mmHg
~45%
All measured with PEEP ≥ 5 cmH₂O. Most common patient profile: critically ill adult with sepsis or pneumonia, often requiring mechanical ventilation.
Most Common Causes of ARDS
Cause
Approx %
Sepsis
~40–50%
Pneumonia
~30–40%
Aspiration
~10–15%
Trauma / contusion
~5–10%
Pancreatitis
~3–5%
Massive transfusion (TRALI)
~2–5%
Inhalational injury
< 2%
Direct (Pulmonary) Causes
Pneumonia (bacterial, viral, fungal)
Aspiration of gastric contents
Pulmonary contusion, inhalation injury
Near-drowning
Indirect (Extrapulmonary) Causes
Sepsis (most common overall cause)
Pancreatitis
Massive transfusion / TRALI
Burns, trauma, DIC
Drug overdose (heroin, aspirin, cocaine)
Stepwise Pathophysiology
ARDS occurs through three overlapping phases. The key physiologic problem is shunt hypoxemia -blood passes through non-ventilated alveoli, so oxygen therapy alone often fails.
1. Exudative Phase (First 7 Days)
Initial inflammatory injury.
Step
Pathology
Lung insult
Infection, aspiration, trauma
Macrophage activation
Cytokine release (TNF-α, IL-1, IL-6)
Neutrophil recruitment
Endothelial damage
↑ Capillary permeability
Protein-rich edema floods alveoli
Alveolar flooding
Impaired gas exchange, ↓ compliance, shunt physiology
Results: ↓ compliance, severe hypoxemia, shunt physiology. Lungs become stiff, small (baby lung concept -only ~30% of lung is recruitable).
2. Proliferative Phase (7–21 Days)
Repair begins.
Process
Effect
Type II pneumocyte proliferation
Surfactant restoration
Fibroblast activation
Collagen deposition
Alveolar repair
Partial recovery
3. Fibrotic Phase (≥ 21 Days)
Occurs in severe/prolonged cases. Pulmonary fibrosis → stiff lungs → reduced compliance → prolonged ventilation. Not all patients progress to this phase.
Preventing ventilator-induced lung injury is critical
🧪 Workup & Diagnosis
Diagnostic Workup
Test
Purpose
ABG
Calculate P/F ratio (PaO₂ ÷ FiO₂). P/F < 300 = ARDS by Berlin criteria. Most important diagnostic step.
CXR
Bilateral opacities not explained by effusion or collapse (Berlin criterion)
Echo (bedside)
Rule out cardiogenic pulmonary edema (PCWP > 18 argues against ARDS). Fastest way to exclude cardiac cause.
BNP / NT-proBNP
Further differentiates cardiogenic vs non-cardiogenic edema
CBC, CMP, coags, lactate, procalcitonin
Assess severity, organ dysfunction, identify sepsis
Blood cultures
Identify infectious cause (sepsis = most common etiology)
CT chest
Dependent consolidation, ground glass opacities. Rules out PE/effusion. Not required for diagnosis.
BAL / sputum cultures
Identify infectious precipitant; obtain after securing airway
ARDS vs Cardiogenic Pulmonary Edema
Feature
ARDS
Cardiogenic
PCWP
Normal (≤ 18 mmHg)
High (> 18 mmHg)
BNP
Normal or mildly elevated
High
Cause
Lung injury (sepsis, pneumonia, aspiration)
Heart failure
Edema fluid
Protein-rich exudate
Transudate
CXR pattern
Diffuse bilateral, peripheral
Perihilar "bat wing", Kerley B lines
Response to diuresis
Minimal improvement
Significant improvement
Heart size
Normal
Often enlarged
Key differentiator: ARDS = normal filling pressures, no response to diuretics, diffuse bilateral disease. Cardiogenic = elevated filling pressures, responds to diuresis, often perihilar pattern. Echo is the fastest way to differentiate at the bedside.
🚨 Management
Lung-Protective Ventilation ARDSNet, 2000
This is the only intervention proven to reduce mortality in ARDS.ARDSNet, 2000 showed a 9% absolute mortality reduction with 6 mL/kg vs 12 mL/kg PBW. Low tidal volumes save lives. Do not let anyone override this for "patient comfort" without a very good reason.
Tidal Volume
6 mL/kg of Predicted Body Weight (PBW) -NOT actual body weight. Start at 6–8 mL/kg, titrate down to 6 mL/kg. SSC, 2021: strong recommendation, high quality evidence. PBW male = 50 + 2.3 × (height in inches − 60) PBW female = 45.5 + 2.3 × (height in inches − 60)
If Pplat remains > 30 after reducing to 6 mL/kg, reduce further to as low as 4 mL/kg PBW. Increase RR to max 35 to maintain minute ventilation.
Plateau Pressure
Keep Pplat ≤ 30 cmH₂OSSC, 2021 -strong recommendation, moderate quality evidence. If above, reduce TV further (down to 4 mL/kg).
Driving pressure (Pplat − PEEP) < 12–15 cmH₂O may be advantageous in patients without spontaneous breathing LUNG SAFE, 2016. Higher plateau pressures correlated with mortality; the relationship was strongest above 29 cmH₂O.
PEEP Strategy
SSC, 2021: suggests higher PEEP over lower PEEP in moderate-severe ARDS (weak recommendation, moderate evidence). Patient-level meta-analysis PEEP Meta-Analysis, 2010 found mortality benefit with higher PEEP only in P/F ≤ 200.
ARDSNet Lower PEEP / FiO₂ Table:
FiO₂
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
PEEP
5
5–8
8–10
10
10–14
14
14–18
18–24
ARDSNet Higher PEEP / FiO₂ Table (moderate-severe):
FiO₂
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
PEEP
12
14
16
18
18
20
22
22–24
Target: SpO₂ 88–95% or PaO₂ 55–80 mmHg.
Permissive Hypercapnia
Acceptable to allow PaCO₂ to rise (up to 50–60 mmHg) to achieve lung-protective goals. pH > 7.20 is generally tolerated. Contraindicated in raised ICP, sickle cell crisis. No single mode (VC vs PC) has demonstrated superiority as long as lung-protective principles are respected.
Prone Positioning (P/F < 150)
Prone ≥ 16 hours/dayPROSEVA, 2013 -reduced 28-day mortality from 32.8% to 16% in severe ARDS. SSC, 2021: strong recommendation, moderate quality evidence for > 12 hours daily.
Improves V/Q matching, recruits dependent lung, reduces compression by mediastinum. Meta-analysis confirmed benefit when applied within 36 hours of intubation for > 12 hrs/day in P/F < 200 Munshi, 2017. Associated with increased pressure sores (RR 1.22) but no increase in accidental extubation.
🔄 Updated Practice: Old teaching: prone positioning is a rescue maneuver for refractory hypoxemia. Current practice: prone positioning is now standard of care for moderate-severe ARDS (P/F <150). PROSEVA (2013) showed 16 hours/day of proning reduced 28-day mortality from 33% to 16%, one of the largest mortality benefits ever seen in ARDS. Initiate proning early (within 12-24h), not as a last resort.
Conservative Fluid Strategy
After initial resuscitation, target even to negative fluid balance. FACTT, 2006: conservative fluid strategy reduced vent days by ~2.5 days without worsening renal function or shock. Use CVP or PAOP-guided diuresis. Avoid fluid overload -it worsens pulmonary edema and prolongs mechanical ventilation.
Neuromuscular Blockade
ACURASYS, 2010: 48h cisatracurium infusion in P/F < 150 showed 90-day mortality benefit vs deep sedation alone (RR 0.71). ROSE, 2019: no benefit vs light sedation with PRN boluses (RR 0.99).
SSC, 2021: suggests intermittent NMBA boluses over continuous infusion (weak recommendation, moderate evidence). Overall, NMBAs reduce barotrauma (RR 0.55). ATS, 2024: conditional recommendation for NMBAs in early (<48h) severe ARDS (P/F ≤ 100). Cisatracurium preferred, may have anti-inflammatory pleiotropic effects. Typical dosing: 15 mg bolus then 37.5 mg/hr × 48h.
If NMBAs used, ensure adequate sedation and analgesia.
🔄 Updated Practice: Old teaching: set PEEP as high as possible to recruit alveoli in ARDS. Current practice: driving pressure (plateau pressure minus PEEP) is the ventilatory variable most strongly associated with survival (Amato, NEJM 2015). Target driving pressure <15 cmH2O. Higher PEEP is beneficial in moderate-severe ARDS (P/F <200) but not in mild ARDS (PEEP Meta-Analysis, 2010). The ART trial (2017) showed aggressive recruitment maneuvers increased mortality.
ECMO Referral
Consider VV-ECMO if P/F < 80 despite optimal settings, pH < 7.15, or plateau pressure > 35 cmH₂O. EOLIA, 2018: supports VV-ECMO as rescue in severe ARDS at experienced centers. SSC, 2021: weak recommendation, low quality evidence. ATS, 2024: conditional recommendation for VV-ECMO in selected severe ARDS (pooled RR 0.76; 95% CI 0.60–0.95; moderate certainty). Refer early -do not wait until irreversible organ failure.
Oxygenation Strategy Before Intubation
High-Flow Nasal Cannula (HFNC)
SSC, 2021: suggests HFNC over NIV for sepsis-induced hypoxemic respiratory failure (weak recommendation, low quality evidence). FLORALI, 2015: HFNC improved 90-day survival vs NIV (OR 0.42) and reduced intubation in severe hypoxemia (P/F ≤ 200): 35% vs 58%. HFNC provides flows up to 60 L/min, FiO₂ up to 100%, with washout of nasopharyngeal dead space and modest PEEP effect (~3–5 cmH₂O).
NIV in ARDS:SSC, 2021 issued no recommendation for NIV vs invasive ventilation in sepsis-induced hypoxemic respiratory failure. LUNG SAFE, 2016: NIV used in 15% of ARDS with higher failure rates in severe disease. NIV failure is an independent mortality risk factor. If trialing NIV: monitor closely for Vt, work of breathing, and need for intubation.
Corticosteroids in ARDS
Steroids have an evolving role in ARDS -evidence now supports early dexamethasone in moderate-to-severe ARDS.
Early dexamethasone in moderate-to-severe ARDS (P/F ≤ 200):DEXA-ARDS, 2020: dexamethasone 20 mg IV daily × 5 days → 10 mg daily × 5 days. Reduced 60-day mortality (21% vs 36%, p=0.0047) and increased ventilator-free days. Start within 30h of ARDS diagnosis. This applies to non-COVID ARDS. Supported by CoDEX, 2020, which also showed dexamethasone increased ventilator-free days in moderate-severe ARDS.
Unresolving/fibroproliferative ARDS (after day 7):ARDS Steroid Trial, 2007: methylprednisolone 1 mg/kg/day with slow taper improved LIS score and reduced mechanical ventilation days. Do NOT start after day 14 -ARDSNet LaSRS, 2006: late initiation associated with increased 60- and 180-day mortality.
COVID-19 ARDS:RECOVERY, 2020: dexamethasone 6 mg/day × 10 days reduced 28-day mortality in patients on mechanical ventilation (29.3% vs 41.4%). CAPE COVID, 2020 found that low-dose hydrocortisone did not significantly reduce treatment failure in COVID pneumonia. REMAP-CAP, 2021 showed IL-6 inhibitors (tocilizumab, sarilumab) improved organ support-free days and survival in severe COVID when combined with corticosteroids.
🆕 ATS 2024 Update: The ATS now formally recommends corticosteroids for ARDS (conditional recommendation, moderate certainty). Pooled analysis: RR 0.84 (95% CI 0.73–0.96) for mortality reduction. Optimal regimen remains unknown, DEXA-ARDS protocol (above) is the most studied. ATS ARDS Guideline, 2024
What Does NOT Work in ARDS
Therapy
Outcome
Late steroids (> day 14)
↑ mortality when started after day 14 ARDSNet LaSRS, 2006. Early dexamethasone (within 30h) IS beneficial -see above.
Inhaled nitric oxide (iNO)
Transient oxygenation improvement only. No mortality benefit. Increases renal dysfunction.
Surfactant
Effective in neonatal RDS. Ineffective in adult ARDS.
Increased 28-day mortality (RR 1.12). ART, 2017ATS, 2024: strong recommendation against prolonged recruitment maneuvers. Higher PEEP WITHOUT recruitment maneuvers is conditionally recommended for moderate-severe ARDS.
IV beta-agonists (albuterol)
Increased mortality. BALTI-2, 2012
💊 Medications & Doses
Sedation & Analgesia
Analgesia-first, target light sedation (RASS 0 to −2).PADIS, 2018 guidelines recommend protocolized sedation with daily awakening trials. PADIS Update, 2025: dexmedetomidine now suggested over propofol when light sedation and/or delirium reduction are priorities. Deep sedation (RASS −4/−5) only when NMBAs required.
Drug
Dose
Indication
Notes
Fentanyl (Sublimaze)
25–200 mcg/hr IV
Analgesia (first-line)
Analgesia-first approach. Less histamine release and hypotension than morphine. Accumulates with hepatic/renal failure.
Propofol (Diprivan)
5–50 mcg/kg/min IV
Sedation (first-line)
Rapid on/off -ideal for daily awakening trials. Monitor triglycerides q48h. Propofol infusion syndrome risk if > 80 mcg/kg/min > 48h.
Dexmedetomidine
0.2–1.5 mcg/kg/hr IV
Light sedation (no NMBAs)
Preserves respiratory drive. Less delirium than benzos. May cause bradycardia/hypotension. Not appropriate for deep sedation.
Midazolam (Versed)
0.02–0.1 mg/kg/hr IV
Sedation (2nd-line)
Accumulates in renal/hepatic failure → prolonged wake-up. Associated with more delirium. Avoid long-term use.
Neuromuscular Blockade
Drug
Dose
Indication
Notes
Cisatracurium (bolus)
0.1–0.2 mg/kg IV PRN
Intermittent use in mod-severe ARDS SSC, 2021
Preferred strategy per SSC 2021. Monitor ventilator synchrony. Does not require train-of-four for intermittent dosing.
Cisatracurium (infusion)
0.1–0.2 mg/kg/hr IV × 48h
Severe ARDS with refractory dyssynchrony
ACURASYS, 2010: mortality benefit vs deep sedation. ROSE, 2019: no benefit vs light sedation + boluses. Monitor with train-of-four (target 1–2/4).
Other ARDS Medications
Drug
Dose
Indication
Notes
Methylprednisolone (Solu-Medrol)
1 mg/kg/day IV → taper over 2 wks
Unresolving ARDS (fibroproliferative phase, day 7–14)
ARDS Steroid Trial, 2007. Do NOT start after day 14 ARDSNet LaSRS, 2006: late steroids = ↑ mortality.
Dexamethasone (early)
20 mg IV daily × 5d → 10 mg × 5d
Moderate-severe ARDS (P/F ≤ 200), start within 30h
DEXA-ARDS, 2020: reduced 60-day mortality (21% vs 36%) and ↑ ventilator-free days in non-COVID ARDS.
Dexamethasone (COVID)
6 mg IV/PO daily × 10 days
COVID-19 ARDS
RECOVERY, 2020: NNT 8 in ventilated COVID patients.
Furosemide (Lasix)
Titrated to even/negative fluid balance
Conservative fluid strategy
FACTT, 2006. Start after resuscitation phase. Monitor Cr and K⁺ closely. CVP or PAOP guidance if available.
Sodium Bicarbonate
1–2 mEq/kg IV slow push or infusion
pH < 7.15 with permissive hypercapnia
Use sparingly. Does not improve outcomes. Temporizing for severe acidemia only.
📋 On Rounds
On Rounds
Pimp Questions
What tidal volume should you use in ARDS and why?
6 mL/kg of ideal body weight. Higher tidal volumes cause volutrauma (overdistension) and worsen alveolar injury. ARDSnet 2000: 22% relative reduction in mortality with 6 vs 12 mL/kg PBW -the single most impactful ARDS trial ever done.
When do you prone a patient and what is the evidence?
P/F ratio < 150 despite optimal ventilator settings. PROSEVA 2013 prone ≥ 16 hrs/day reduced 28-day mortality from 32.8% to 16% -one of the most dramatic results in critical care medicine.
What is permissive hypercapnia and why do we accept it?
Allowing PaCO₂ to rise above normal (up to ~60 mmHg) as a trade-off for achieving lung-protective tidal volumes. Increasing minute ventilation to normalize CO₂ would require higher tidal volumes that cause further lung injury. pH > 7.20 is generally safe. Contraindicated in raised ICP and sickle cell crisis.
What is driving pressure, and why does it matter more than plateau pressure alone?
Driving pressure = Pplat − PEEP. It reflects the cyclic strain on functional lung tissue (the "baby lung"). A patient-level meta-analysis Driving Pressure Meta-Analysis, 2015 found driving pressure < 15 cmH₂O was the strongest independent predictor of survival in ARDS -better than Vt or Pplat alone. It accounts for both the tidal volume and the functional lung size.
ACURASYS vs ROSE -how do you reconcile conflicting NMBA data?
ACURASYS, 2010 compared 48h cisatracurium infusion vs deep sedation without NMBAs → mortality benefit. ROSE, 2019 compared infusion vs light sedation with PRN boluses → no benefit. The difference was the control arm: it's the deep sedation that was harmful, not the NMBAs that were magical. The lesson: avoid deep sedation; use light sedation with PRN NMBA boluses as first-line SSC, 2021.
When should you start thinking about ECMO?
P/F < 80 despite optimal vent settings (PEEP optimized, Pplat ≤ 30, TV 6 mL/kg PBW), prone positioning, and trial of NMBAs. Also consider for pH < 7.15 from respiratory acidosis or Pplat > 35 despite TV reduction to 4 mL/kg. EOLIA, 2018 showed benefit when referred early to experienced ECMO centers. Key: refer early -don't wait for irreversible multi-organ failure.
Why should you avoid fluid overload in ARDS, and what trial supports conservative fluids?
FACTT, 2006 randomized 1,000 ARDS patients to conservative vs liberal fluid management after initial resuscitation. Conservative strategy: ~2.5 fewer ventilator days, improved oxygenation index, no increase in shock or renal failure. Mechanism: reduced hydrostatic pressure across damaged pulmonary capillaries → less alveolar edema. Target even or negative daily fluid balance once resuscitation is complete.
What is the definition of ARDS?
Acute diffuse inflammatory lung injury → increased alveolar-capillary permeability → pulmonary edema → severe hypoxemia. Diagnosed by Berlin criteria: acute onset ≤ 1 week, bilateral CXR opacities, not cardiogenic, P/F ratio determines severity.
What are the Berlin severity classifications?
Mild: P/F 200–300 (~27% mortality). Moderate: P/F 100–200 (~32% mortality). Severe: P/F < 100 (~45% mortality). All with PEEP ≥ 5 cmH₂O.
What is the most common cause of ARDS?
Sepsis (~40–50%), followed by pneumonia (~30–40%). Sepsis is the most common indirect cause; pneumonia is the most common direct (pulmonary) cause.
Why does hypoxemia occur in ARDS?
Shunt physiology -blood passes through non-ventilated, fluid-filled alveoli without participating in gas exchange. This is why supplemental O₂ alone often fails to correct the hypoxemia, and why PEEP (to recruit collapsed alveoli) is critical.
What plateau pressure should you target?
Pplat ≤ 30 cmH₂O. Additionally, driving pressure (Pplat − PEEP) < 15 cmH₂O is the strongest independent predictor of survival Driving Pressure Meta-Analysis, 2015.
How do you differentiate ARDS from cardiogenic pulmonary edema?
ARDS: normal PCWP (≤ 18), normal BNP, protein-rich exudate, diffuse bilateral CXR, no response to diuretics. Cardiogenic: high PCWP, high BNP, transudative, perihilar "bat wing" pattern, responds to diuresis. Bedside echo is the fastest differentiator.
Clinical Examples
📋 Case 1, Pneumonia-Induced ARDS
Patient: 55M, PMH DM2. Severe CAP (Strep pneumoniae). Intubated for hypoxemic respiratory failure.
Key findings: P/F 120 (moderate ARDS). Bilateral infiltrates. BNP 45. TV 420 mL (6 mL/kg PBW), PEEP 12, FiO2 0.7. Pplat 28, driving pressure 16.
Driving pressure 16, reduce below 15 Amato et al., 2015
Conservative fluid strategy FACTT, 2006
P/F < 150, prone ≥ 16h/day PROSEVA, 2013
Light sedation (RASS -1 to -2), daily SAT/SBT assessment
Teaching point: Driving pressure (Pplat - PEEP) < 15 is the strongest predictor of survival in ARDS.
📋 Case 2, Severe ARDS Requiring Proning
Patient: 40F, previously healthy. Influenza A pneumonia. P/F 72 (severe) despite FiO2 1.0, PEEP 16.
Key findings: TV 330 mL (6 mL/kg PBW), Pplat 30, driving pressure 14. SpO2 85% supine.
Management:
Prone immediately ≥ 16h/day PROSEVA, 2013
Cisatracurium PRN boluses for dyssynchrony, not routine infusion ROSE, 2019
Light sedation (RASS -2), avoid deep sedation
If P/F remains < 80 after proning, consult ECMO center EOLIA, 2018
Oseltamivir 75 mg BID for influenza
Teaching point: PROSEVA reduced mortality from 32.8% to 16%. ACURASYS vs ROSE: deep sedation was harmful, not paralytics magical. Use light sedation + PRN NMBA boluses.
📋 Case 3, ARDS vs Cardiogenic Pulmonary Edema
Patient: 68M, PMH HFrEF (EF 25%). Bilateral infiltrates, intubated. P/F 180. Is this ARDS or decompensated HF?
Key findings: BNP 2800. Echo: EF 20%, dilated LV. Responds to IV furosemide. Cardiogenic pulmonary edema, NOT ARDS.
Management:
IV furosemide drip, target negative fluid balance
Do NOT apply low-TV strategy reflexively, volume overload, not ARDS
Teaching point: Berlin criteria require bilateral opacities NOT fully explained by cardiac failure. ARDS = normal BNP/PCWP, no diuretic response. Cardiogenic = elevated BNP/PCWP, responds to diuresis.
📋 Sample Presentation
"Mr. Torres is a 52-year-old with no significant PMH who developed ARDS in the setting of severe CAP with Streptococcus pneumoniae. He was intubated on hospital day 1. He is on lung-protective ventilation: TV 6 mL/kg PBW at 390 mL, PEEP 12, FiO₂ 0.7, with a P/F ratio of 148 this morning -consistent with moderate ARDS. He was proned for 16 hours overnight with improvement in P/F to 180. His plateau pressure is 26. He is on propofol and fentanyl drips, RASS −2. We are on day 2 of cisatracurium. Fluid balance is negative 400 mL over the last 24 hours. He remains hemodynamically stable on low-dose norepinephrine. Plan is to continue prone cycling and target daily fluid balance of at least even."
Daily Ventilator Assessment
P/F ratio -calculate every morning from ABG. Trend drives all major decisions (prone, ECMO).
Assess daily once P/F > 200 and FiO₂ ≤ 0.4 with PEEP ≤ 8:
Precipitant resolving or resolved
Hemodynamically stable (off or low-dose vasopressors)
Adequate cough and gag reflex
RASS −1 to +1 (awake, cooperative)
No planned surgery or procedures requiring deep sedation
Rapid shallow breathing index (RSBI) < 105 breaths/min/L
SBT Protocol: 30–120 min on PS 5–8 / PEEP 5 or T-piece. Pass = RR < 35, SpO₂ > 90%, HR < 140, no accessory muscle use, no distress. → Extubate. If fails → resume full support, retry in 24h. WIND, 2018: daily SBTs reduce time to extubation.
Complications to Watch
Ventilator-associated pneumonia (VAP) -new fever, purulent sputum, new infiltrate on CXR after 48h of MV. Maintain HOB ≥ 30°, oral care, subglottic suctioning.
ICU-acquired weakness -from NMBAs, steroids, immobility. Early mobilization when safe Early Mobilization Trial, 2009.
Delirium -screen daily with CAM-ICU. Minimize benzos, sleep hygiene, early mobilization.
RV failure -from high PEEP and pulmonary vasoconstriction. Monitor with echo. Reduce PEEP if RV dilation/failure suspected.
Renal failure -common in ARDS. May be from underlying sepsis, contrast, or positive pressure effects on renal perfusion.
⚡ Summary
Summary
Berlin Criteria Define It
Acute onset within 1 week of a known insult, bilateral opacities not fully explained by effusion or collapse, respiratory failure not fully explained by cardiac failure or fluid overload, and impaired oxygenation on at least 5 cmH₂O of PEEP.Severity by P/F ratio: mild 200 to 300, moderate 100 to 200, severe below 100.
Low Tidal Volume Is the Intervention That Saves Lives
6 mL/kg of predicted body weight, calculated from height and sex, not actual weight, because lung size tracks height. ARMA showed a mortality reduction from 40% to 31% with this alone. Keep plateau pressure below 30 cmH₂O and driving pressure below 15, since driving pressure is the variable most closely associated with survival.
Accept Permissive Hypercapnia
Tolerate a rising CO₂ and a pH down to about 7.20 rather than raising the tidal volume.The ventilator injures the lung; the CO₂ largely does not. Raise the respiratory rate first, and use bicarbonate only if the acidemia is causing hemodynamic compromise.
Prone Early in Severe Disease
P/F below 150 for at least 16 h per session.PROSEVA showed a large mortality reduction, from recruitment of dependent lung and more uniform distribution of ventilation. Prone early rather than as a last resort, and treat pressure areas, tube security and line management as the main risks of the procedure.
Use Paralysis and Steroids Selectively
Neuromuscular blockade for severe early ARDS with ventilator dyssynchrony: ACURASYS suggested benefit but ROSE, with lighter sedation in the control arm, did not, so it is not routine. Steroids have evidence in moderate-to-severe ARDS (DEXA-ARDS) and in COVID-related disease, but avoid starting them late in established fibroproliferative ARDS, where harm was seen.
Keep Them Dry Once They Are Stable
A conservative fluid strategy after shock has resolved improves oxygenation and shortens ventilator days (FACTT), without increasing renal failure. Resuscitate the shocked patient first, then dry them out: the sequence matters, and continuing liberal fluids into the stable phase is the commoner error.
Separate It From Cardiogenic Edema
ARDS: no cardiomegaly, peripheral and patchy opacities, normal or low BNP, no response to diuresis alone.Cardiogenic edema: cardiomegaly, central bat-wing distribution, effusions, raised BNP, responds to diuresis.Echocardiography settles it and should be done early rather than after a failed diuretic trial.
Escalate in a Defined Order
Optimize the ventilator, then prone, then consider inhaled pulmonary vasodilators as a temporizing measure, then refer for VV-ECMO.Refer early to an ECMO center (EOLIA), since transferring a patient after multiorgan failure has set in is far less successful. Throughout, treat the underlying cause: ARDS is a syndrome, and the sepsis, pancreatitis or aspiration driving it determines the outcome.
From the decision to intubate through vent settings, oxygenation vs ventilation, troubleshooting, sedation, and weaning to extubation. Everything you need to manage the airway and the ventilator.
Impending respiratory failure -accessory muscle use, paradoxical breathing, rising work of breathing
Try NIV First (if appropriate): BiPAP/CPAP for COPD exacerbation, cardiogenic pulmonary edema, and mild-moderate hypoxemia. Avoid NIV in decreased consciousness, vomiting, hemodynamic instability, or inability to cooperate.
Key Vent Concepts
Pressure vs Volume
Volume Control (VC): You set the tidal volume -the vent delivers exactly that volume. Pressure varies. Preferred in ARDS (tight TV control).
Pressure Control (PC): You set the pressure -the volume varies depending on lung compliance. Preferred when you want to limit pressures.
Key Numbers to Know Every Morning
Tidal volume (Vt) -actual delivered TV in mL/kg PBW
▶ How to Pick BiPAP Settings, Step by Step (tap to expand)
Understanding IPAP, EPAP & Pressure Support
The Key Concept: BiPAP delivers two pressures. IPAP (Inspiratory Positive Airway Pressure) is the pressure during inhale. EPAP (Expiratory Positive Airway Pressure) is the pressure during exhale (functionally identical to PEEP). The difference between them is Pressure Support (PS) = IPAP − EPAP. PS is what actually pushes air into the lungs and generates tidal volume.
Start 5 cmH₂O. ↑ by 2 if SpO₂ < 90% despite FiO₂. Max ~10-12.
= PEEP. Treats the O₂ problem.
IPAP
Ventilation (how much air is pushed in per breath)
Start 10 cmH₂O. ↑ by 2 q15-30 min if CO₂ still high. Max ~20-25.
= Tidal volume driver. Treats the CO₂ problem.
PS (= IPAP − EPAP)
Tidal volume per breath
Higher PS → bigger breaths → more CO₂ blown off. Target PS 5-15 cmH₂O for most patients.
PS is essentially your tidal volume knob. PS of 10 ≈ TV of ~400-500 mL in most adults.
FiO₂
Oxygen concentration
Start 100%, wean to target SpO₂ 88-92% (COPD) or 92-96%. Always wean FiO₂ before weaning pressures.
Supplemental O₂. Independent of IPAP/EPAP.
Rate (backup)
Minimum breaths/min if patient doesn't trigger
Set 12-16. Usually not needed, patient triggers their own breaths.
Safety net for apnea.
The Two Knobs: Fix O₂ vs Fix CO₂
Problem
Which Knob to Turn
What to Do
SpO₂ low (oxygenation failure)
↑ EPAP (or ↑ FiO₂)
EPAP recruits alveoli and improves V/Q matching. Think of it like adding PEEP on a vent.
CO₂ high (ventilation failure)
↑ IPAP (keeping EPAP the same)
This increases PS, which increases tidal volume, which blows off more CO₂. ↑ IPAP by 2 cmH₂O every 15-30 min until pH improves.
Both
↑ EPAP for O₂, ↑ IPAP for CO₂
Always increase IPAP at least as much as EPAP to maintain the PS gap. If you raise EPAP by 2, raise IPAP by 2 also.
⚠️ Critical Rule: If you increase EPAP without increasing IPAP, you decrease PS, which decreases tidal volume, which can worsen CO₂ retention. Always maintain or increase the PS gap when raising EPAP.
Example: IPAP 12 / EPAP 5 = PS 7. If you raise EPAP to 8 but keep IPAP at 12 → PS drops to 4 → patient gets smaller breaths → CO₂ rises. Fix: raise IPAP to 15 / EPAP 8 = PS 7 maintained.
Starting Protocol & Titration
Step 1: Start BiPAP
IPAP 10 / EPAP 5 (PS = 5) -safe starting point for most patients
FiO₂ 100% (wean later based on SpO₂)
Backup rate 12-16
Fit mask snugly. Coach patient: "Breathe with the machine, let it push air in."
Step 2: Check ABG at 1 Hour
CO₂ still elevated / pH still acidotic? → ↑ IPAP by 2 (e.g., IPAP 12 → 14 → 16). Recheck in 1h.
SpO₂ still low? → ↑ EPAP by 2 (and raise IPAP by 2 to maintain PS). Or ↑ FiO₂.
Both improving? → Hold current settings. Wean FiO₂ first.
Step 3: Reassess at 2 Hours
pH improving and patient comfortable? → BiPAP is working. Continue. Recheck ABG q4-6h.
No improvement or worsening? → NIV failure. Prepare for intubation. Do NOT delay.
Clinical Example: BiPAP Preventing Intubation in COPD
🏥 Scenario: 68M with severe COPD exacerbation
Presentation: Brought in by EMS, severe respiratory distress, accessory muscle use, speaking in 1-2 word sentences. RR 32, SpO₂ 84% on 6L NC, HR 115, BP 155/90.
Overnight: Continue BiPAP. Wean FiO₂ to 35%. Give Ipratropium/Albuterol (DuoNeb) nebs q4h, Methylprednisolone (Solu-Medrol) 60 mg IV daily (= prednisone 40 mg PO; switch to PO when tolerating), Azithromycin (Zithromax) 500 mg IV. Next AM: ABG 7.38 / 48 / 78. Trial off BiPAP → tolerates nasal cannula. Extubation avoided.
✅ Why this worked: Each time we raised IPAP (while keeping EPAP the same), we increased PS → bigger tidal volumes → more CO₂ blown off per breath → pH corrected. The key was titrating IPAP up aggressively every 15-30 minutes until the ABG improved. If by 1-2 hours the pH hadn't improved, this patient would have needed intubation.
Quick Reference: Common BiPAP Settings by Scenario
Scenario
Starting IPAP / EPAP
PS
Goal
Titration Target
COPD exacerbation
10-12 / 5
5-7
↓ CO₂, ↑ pH
↑ IPAP q15-30 min → max 20-25. Target pH > 7.30.
Cardiogenic pulmonary edema
10-12 / 8-10
2-4
↑ O₂, ↓ preload
Higher EPAP for recruitment. CPAP 10-12 is often enough.
Obesity hypoventilation
14-18 / 8-10
6-10
↓ CO₂
Need higher pressures due to chest wall compliance. ↑ IPAP aggressively.
Neuromuscular weakness
10-14 / 5
5-9
Augment weak inspiratory muscles
↑ IPAP if NIF declining. Low threshold for intubation (GBS, MG crisis).
Post-extubation (prophylactic)
8-10 / 5
3-5
Prevent reintubation
Low support. Alternate with HFNC. Wean over 24-48h.
DNI / comfort care
10-15 / 5-8
5-7
Symptom relief
Titrate to comfort + dyspnea relief. No ABG targets.
Special Consideration: The Obese Patient
Obesity makes BiPAP harder. Abdominal and chest wall fat reduces lung compliance, compresses the diaphragm (especially supine), and causes baseline hypoventilation. These patients need more aggressive settings than normal-weight patients.
Challenge
Why It Happens
What to Do
Higher IPAP needed
Chest wall is stiff → needs more pressure to generate the same tidal volume
Start IPAP 14-18 (not 10). May need IPAP 20-25 in BMI > 50. Don't be afraid to go higher.
Start EPAP 8-10 (not 5). Acts like higher PEEP to recruit collapsed bases.
Positioning matters hugely
Supine = diaphragm splinted by abdomen. Functional residual capacity drops.
Sit patient upright at 30-45° or reverse Trendelenburg. This alone can improve oxygenation dramatically.
Chronic CO₂ retention
Obesity hypoventilation syndrome (OHS), chronic hypercapnia with elevated bicarb
Don't normalize CO₂. Target their baseline PaCO₂ (often 50-60). Check HCO₃, if elevated, it's chronic. Over-ventilating → alkalosis → arrhythmias.
Mask leak
Facial fat makes mask seal harder
Use a full-face mask (oronasal). May need a larger size. Check for beard. Tighten straps but avoid skin breakdown.
💡 Practical Example, BMI 48 with OHS Exacerbation:
Patient arrives with pH 7.18, PaCO₂ 95, HCO₃ 34 (chronic + acute). SpO₂ 82%.
• Start: IPAP 18 / EPAP 10 (PS = 8), FiO₂ 40%, upright positioning
• 15 min: SpO₂ 88%, still tachypneic → ↑ IPAP to 22 (PS = 12)
• 1 hour ABG: pH 7.25, PaCO₂ 75. Improving. Hold settings.
• Target: pH > 7.30 and PaCO₂ toward their baseline (~55-60). Do NOT target PaCO₂ 40, that's over-ventilation for this patient.
When NIV is Failing -Escalate to Intubation
⚠️ Signs of NIV failure (reassess within 1–2 hours):
• No improvement in pH or PaCO₂ after 1–2h of BiPAP
• Worsening tachypnea (RR > 30 despite NIV)
• SpO₂ < 90% despite FiO₂ escalation
• Declining mental status (somnolence, confusion)
• Hemodynamic instability
• Patient intolerance / non-compliance with mask Do NOT delay intubation if NIV is failing. Late intubation = worse outcomes.
🚨 Rapid Sequence Intubation (RSI)
The 7 P's of RSI
1
Preparation Equipment: ETT (7.0–7.5 women, 7.5–8.0 men), laryngoscope (video preferred), bougie, BVM, suction, end-tidal CO₂, backup airway (LMA). Two IV lines. Monitors on. Confirm code status.
2
Pre-oxygenation 3–5 minutes of 100% O₂ via NRB or HFNC 60L/min (builds O₂ reserve in FRC). Goal: SpO₂ 100%. In obese or critically ill → apneic oxygenation: leave NC at 15L under the NRB or continue HFNC during intubation attempt.
3
Pre-treatment (optional) Fentanyl 1–3 mcg/kg IV (blunts sympathetic surge -useful in elevated ICP, aortic dissection). Lidocaine 1.5 mg/kg IV (for elevated ICP -controversial). Most patients skip this step.
4
Paralysis with Induction (push simultaneously) See drug table below. Induction agent → wait 20–30 seconds → paralytic.
5
Protection & Positioning Sniffing position: neck flexed, head extended (aligns oral-pharyngeal-laryngeal axes). Elevate head of bed 20–30° in obese. Apply cricoid pressure (Sellick maneuver -controversial but still used).
6
Placement Direct or video laryngoscopy → visualize cords → pass tube through cords → inflate cuff → confirm placement: (1) End-tidal CO₂ waveform (gold standard), (2) bilateral breath sounds, (3) misting in tube, (4) CXR for depth (2–4 cm above carina).
7
Post-intubation Management Start sedation (propofol or midazolam + fentanyl). Set initial vent settings. Secure tube (tape or holder). NG/OG tube. Arterial line if not already placed. ABG in 30 min. CXR to confirm ETT position.
RSI Drug Table
Drug
MOA
Dose
Onset
Duration
Best For
⚠️ Avoid If
INDUCTION AGENTS
Etomidate
GABA-A agonist
0.3 mg/kg IV push
15–30 sec
5–15 min
Hemodynamically unstable -most neutral on BP. Most common RSI induction agent.
⚠️ Adrenal suppression (single dose is clinically insignificant). Avoid in septic shock? -debated.
Ketamine (Ketalar)
NMDA antagonist
1–2 mg/kg IV push
30–60 sec
10–20 min
Asthma/bronchospasm (bronchodilator), hypotension (preserves BP via sympathetic stimulation), elevated ICP (old teaching said avoid -now considered safe).
Non-depolarizing NMB -competitive ACh blocker at nicotinic receptor
1.2 mg/kg IV push (RSI dose)
45–60 sec
45–70 min
When succinylcholine is contraindicated. Reversible with sugammadex (16 mg/kg for immediate reversal). Becoming first-line at many centers.
⚠️ Long duration -if can't intubate AND can't ventilate, patient is paralyzed for 45+ min (unless sugammadex available).
⚠️ Cannot Intubate, Cannot Oxygenate (CICO) -Surgical Airway
If 2 intubation attempts fail AND cannot bag-mask ventilate AND LMA fails → cricothyrotomy. Palpate cricothyroid membrane (between thyroid and cricoid cartilage) → vertical skin incision → horizontal stab through membrane → insert bougie → railroad 6.0 ETT or cric tube. This is the final rescue. Do not delay.
Difficult Airway Predictors (LEMON): L ook externally (short neck, obesity, facial trauma, beard) E valuate 3-3-2 (3 fingers mouth opening, 3 fingers hyoid-to-chin, 2 fingers thyroid notch-to-floor of mouth) M allampati score (III/IV = harder) O bstruction (epiglottitis, angioedema, tumor, hematoma) N eck mobility (c-spine collar, ankylosing spondylitis, rheumatoid arthritis)
⚠️ No backup rate -if patient becomes apneic, no breaths are delivered. Need apnea backup alarm.
APRV Airway Pressure Release Ventilation
Sustained high pressure (P-high) with brief releases to low pressure (P-low) for CO₂ clearance. Essentially inverse-ratio CPAP.
P-high, T-high, P-low, T-low
TV during releases
Refractory ARDS -keeps alveoli open with sustained high pressure. Allows spontaneous breathing.
⚠️ Complex to manage. Requires experience. Not proven superior to standard lung-protective ventilation. Hemodynamic effects from sustained high intrathoracic pressure.
Quick Decision: Which Mode?
Scenario
Mode
Why
Fresh intubation (default)
AC/VC
Guarantees tidal volume. Simple. Predictable.
ARDS
AC/VC (6 mL/kg PBW)
Must control TV tightly for lung protection.
COPD / asthma
AC/VC (low rate, long I:E)
Need guaranteed TV with long expiratory time to avoid air trapping.
High peak pressures
Switch AC/VC → AC/PC
Limits pressure delivery. But monitor TV -may drop.
Ready to wean / SBT
PSV 5–8 / PEEP 5
Minimal support. Tests if patient can breathe independently.
Refractory ARDS
APRV (by experienced team)
Last resort before ECMO. Keeps alveoli recruited.
🫁 Oxygenation vs Ventilation
The Most Important Concept on the Vent
Oxygenation and ventilation are two completely separate physiologic processes. They are fixed by different vent settings. Confusing them is the #1 mistake interns make in the ICU. If you learn nothing else about the vent, learn this table.
🔵 Oxygenation (O₂)
🔴 Ventilation (CO₂)
What is it?
Getting oxygen INTO the blood
Getting CO₂ OUT of the blood
Measured by
PaO₂ (ABG) or SpO₂ (pulse ox)
PaCO₂ (ABG) or EtCO₂ (capnography)
Normal values
PaO₂ 80–100 mmHg, SpO₂ 94–98%
PaCO₂ 35–45 mmHg
Problem
Hypoxemia -O₂ too low
Hypercapnia -CO₂ too high Hypocapnia -CO₂ too low
Vent settings that fix it
FiO₂ (↑ = more O₂ delivered) PEEP (↑ = recruits collapsed alveoli, improves gas exchange surface area)
Respiratory Rate (↑ RR = blow off more CO₂) Tidal Volume (↑ TV = each breath removes more CO₂) Together = Minute Ventilation (MV = RR × TV)
Think of it as
How much oxygen you're putting IN the lungs
How much air you're moving THROUGH the lungs
Quick Decision Framework
🔵 Patient is HYPOXEMIC (SpO₂ low)
Step 1: ↑ FiO₂ (quick fix -increase the O₂ concentration) Step 2: ↑ PEEP (recruit alveoli -increases surface area for gas exchange) Step 3:Prone positioning -flip patient face-down ≥ 16h/day. Redistributes ventilation to dorsal lung (where perfusion is greatest) → improves V/Q matching. Mortality benefit in severe ARDS (P/F < 150) PROSEVA, 2013 Step 4:Inhaled nitric oxide (iNO) 5–40 ppm or inhaled epoprostenol -selective pulmonary vasodilators. Dilate vessels ONLY in ventilated alveoli → redirects blood flow to functioning lung units → improves V/Q matching + oxygenation. ⚠️ No proven mortality benefit -used as rescue/bridge therapy. Step 5:ECMO (VV-ECMO) -when all above fail. Blood is oxygenated externally. Consider if P/F < 80 despite optimal vent + prone + iNO.
⚠️ Do NOT increase RR or TV -these do not fix oxygenation. Breathing faster doesn't put more O₂ in the blood if the alveoli can't exchange gas.
🔴 Patient is HYPERCAPNIC (CO₂ high)
Step 1: ↑ Respiratory Rate (blow off more CO₂ per minute) Step 2: ↑ Tidal Volume (each breath removes more CO₂) Minute Ventilation = RR × TV → this is what determines CO₂ clearance
Step 3 (if bronchospasm):Heliox (70–80% helium / 20–30% O₂) -helium is less dense than nitrogen → reduces turbulent airflow resistance → gas flows past the obstruction more easily → improves ventilation in severe bronchospasm/upper airway obstruction refractory to bronchodilators. ⚠️ Limitation: Max FiO₂ is 30% (rest is helium), so don't use if patient needs high FiO₂.
⚠️ Do NOT increase FiO₂ or PEEP -these do not remove CO₂. Giving more oxygen doesn't help ventilation. ⚠️ Watch for auto-PEEP: If RR too high (especially in COPD), patient may not fully exhale → air trapping → hemodynamic collapse.
Common Scenarios -What to Adjust
ABG Shows
Problem
Adjust
⚠️ Watch For
PaO₂ 55, SpO₂ 88%
Hypoxemia
↑ FiO₂ and/or ↑ PEEP
FiO₂ > 0.6 for > 24h → O₂ toxicity. Wean FiO₂ first, then PEEP.
PaCO₂ 65, pH 7.22
Respiratory acidosis (hypoventilating)
↑ RR or ↑ TV (↑ minute ventilation)
Auto-PEEP in COPD. Pplat > 30 if TV too high. Max RR ~35 before ineffective.
PaCO₂ 25, pH 7.55
Respiratory alkalosis (overventilating)
↓ RR or ↓ TV (↓ minute ventilation)
Patient may be anxious/in pain → treat the cause. Don't just sedate to fix CO₂.
PaO₂ 55 AND PaCO₂ 60
Both hypoxemic + hypercapnic
↑ FiO₂/PEEP (for O₂) AND ↑ RR/TV (for CO₂). If refractory → prone + iNO + ECMO.
Suggests severe disease (ARDS + dead space). Consider prone, paralytics, iNO, ECMO.
⚠️ Permissive hypercapnia: In ARDS, it's OK to let CO₂ run high (up to 60–70) and pH drop to ~7.20 -as long as oxygenation is maintained. The priority is lung-protective ventilation (TV 6 mL/kg, Pplat ≤ 30). Don't sacrifice lung protection to normalize a CO₂ number. Same principle applies in status asthmaticus (accept PaCO₂ 60–80 with pH > 7.20 to avoid breath stacking and auto-PEEP).
The relationship between PaO₂ (the partial pressure of dissolved O₂) and SpO₂ (% of hemoglobin saturated) is sigmoid, not linear. Memorizing three points on the curve lets you mentally convert between the two at the bedside.
PaO₂ (mmHg)
SpO₂ (%)
What it means
40
70
Mixed venous blood. Severe hypoxemia if arterial.
50
80
Critically low. On the steepest part of the cliff.
60
90
The "knee." Above this you're on the safe plateau; below, on a cliff.
~95-100
97-100
Normal arterial. Far up the plateau.
Bedside shortcut: on the steep part of the curve (SpO₂ 70-90), SpO₂ minus 30 ≈ PaO₂. So an SpO₂ of 88 ≈ PaO₂ ~58. Above SpO₂ 90 the plateau is too flat for this trick to work, small SpO₂ changes hide much larger PaO₂ swings.
Why the curve has a knee at SpO₂ 90 / PaO₂ 60
Above the knee (PaO₂ > 60, SpO₂ > 90): flat plateau. Big PaO₂ changes produce only small SpO₂ changes. PaO₂ 100 vs PaO₂ 80 both look like 96-97% on the pulse ox.
Below the knee (PaO₂ < 60, SpO₂ < 90): steep cliff. Small PaO₂ drops produce massive SpO₂ drops. Crashes look sudden because the curve falls off fast here.
Why this matters for targets: aim for SpO₂ ≥ 92% (general) or 88-92% (COPD CO₂ retainers, permissive hypoxemia in ARDS). Sitting at 92% is at the edge, small drops can plummet quickly.
Curve shifts (the Bohr effect and friends)
Direction
Effect
Caused by
RIGHT shift
Hgb releases O₂ more easily (higher P50). Good for tissues, bad for lungs at low PaO₂.
CADET, face Right: ↑ CO₂, Acidosis, 2,3-DPG (BPG), Exercise, Temperature.
LEFT shift
Hgb holds O₂ tighter (lower P50). Hgb saturates well in the lungs but unloads poorly to tissues.
CO poisoning: SpO₂ reads ~100% even though tissues are profoundly hypoxic. The pulse ox can't distinguish HbCO from HbO₂. Use co-oximetry (carboxyhemoglobin level) on a venous or arterial sample. Treat with 100% O₂ via NRB; hyperbaric for severe cases.
Methemoglobinemia: SpO₂ stuck around 85% regardless of true saturation. Suspect with cyanosis unresponsive to O₂, "chocolate brown" blood, history of dapsone, benzocaine, nitrites, or aniline dyes. Treat with methylene blue 1-2 mg/kg IV (avoid in G6PD deficiency).
P/F ratio = PaO₂ ÷ FiO₂ -the single best number to assess oxygenation on a vent. > 300: Normal 200–300: Mild ARDS 100–200: Moderate ARDS < 100: Severe ARDS → consider prone, paralytics, ECMO
Types of Respiratory Failure
Type
Name
Mechanism
ABG Pattern
Common Causes
Treatment Focus
Type 1
Hypoxemic
Failure of gas exchange -O₂ can't cross alveolar membrane into blood. V/Q mismatch, shunt, diffusion impairment.
🔴 RR × TV (↑ minute ventilation). BiPAP first if possible.
Type 3
Perioperative
Atelectasis from anesthesia, supine positioning, diaphragm splinting (pain, abdominal distension).
PaO₂ low PaCO₂ usually normal
Post-surgical (especially abdominal/thoracic), obesity, poor pain control limiting deep breathing
Incentive spirometry, early mobilization, pain control, CPAP if needed
Type 4
Shock
Hypoperfusion → insufficient O₂ delivery to tissues despite adequate lung function. Respiratory muscles fatigue from hypoperfusion.
Lactic acidosis Mixed picture
Cardiogenic shock, septic shock, hypovolemic shock, Category E PE
Treat the shock first (fluids, vasopressors, inotropes). Intubate to reduce O₂ consumption by respiratory muscles.
Why does this matter? Knowing the type tells you what to fix. Type 1 → fix oxygenation (FiO₂/PEEP). Type 2 → fix ventilation (RR/TV or BiPAP). Type 3 → prevent/reverse atelectasis. Type 4 → fix the circulation, not just the lungs.
📌 Settings
Initial Vent Settings
Parameter
Standard
ARDS
COPD/Obstructive
Mode
AC/VC or AC/PC
AC/VC
AC/VC or SIMV
Tidal Volume
8 mL/kg PBW
6 mL/kg PBW
6–8 mL/kg PBW
Rate
14–16 /min
18–22 /min
10–14 /min (avoid stacking)
FiO₂
Start 1.0, wean
Wean to keep SpO₂ 88–95%
Target SpO₂ 88–92%
PEEP
5 cmH₂O
8–16 (ARDSnet table)
Auto-PEEP concern -keep low
I:E Ratio
1:2
1:2 to 1:3
1:3 to 1:4 (more time to exhale)
📌 Trouble
Acute Deterioration on the Vent -DOPE
Patient suddenly desaturating or high pressures alarm → Call for help + use DOPE mnemonic immediately
D -Displacement
ETT displaced (too deep → right mainstem, or dislodged)
Check: confirm with laryngoscope, CXR, ETCO₂, auscultation
Fix: reposition or replace tube
O -Obstruction
Mucus plug, biting tube, kinked circuit
Check: suction catheter passes easily? Pass suction first
ARDS: TV 6 mL/kg PBW ARDSNet, 2000, PEEP per ARDSNet table, prone if P/F < 150 PROSEVA, 2013
Daily SBT: FiO₂ ≤ 40%, PEEP ≤ 8, following commands → PSV 5/5 × 30 min
Sedation: RASS 0 to −2. Daily SAT before SBT.
💊 Medications
Medications
Drug
Dose
Route
Notes
Propofol (Diprivan)
5–50 mcg/kg/min
IV
First-line sedation. ⚠️ Propofol infusion syndrome (PRIS) risk if > 48h or > 80 mcg/kg/min (check CK, triglycerides, lactate).
Fentanyl (Sublimaze)
25–200 mcg/hr
IV
Analgesia-first approach. Preferred analgesic in ICU. Lipophilic -accumulates > 72h.
Cisatracurium
1–3 mcg/kg/min
IV
Neuromuscular blockade for severe ARDS × 48h. Must have adequate sedation first -paralyzed + aware = torture. ACURASYS, 2010
Dexmedetomidine
0.2–1.5 mcg/kg/hr
IV
Less delirium than benzos MENDS, 2007. SEDCOM, 2009. DEXCOM, 2016: reduced delirium and shorter time to extubation vs midazolam. ⚠️ Bradycardia, hypotension. No respiratory depression -can use during SBT.
NONSEDA, 2020: No sedation vs light sedation in mechanically ventilated patients showed similar outcomes, though no-sedation had more agitation episodes. Supports minimizing sedation depth when feasible.
Cuff leak test: deflate cuff → listen for air leak around tube. No leak suggests laryngeal edema → post-extubation stridor risk → give dexamethasone and delay extubation
Consider dexamethasone 8 mg IV q8h × 4 doses starting 12h before extubation if intubated > 7 days or failed cuff leak
Anesthesia or airway team notified if anticipated difficult reintubation
⚠️ Failed Extubation: Need to reintubate within 48–72 hours -associated with significantly higher mortality (up to 25–50%). Better to wait one more day than to extubate prematurely. Risk factors for failure: age > 65, COPD, HF, weak cough, excessive secretions, high RSBI.
Post-extubation: Apply supplemental O₂ (nasal cannula or HFNC). Monitor closely for 24–48h. If high-risk for reintubation → prophylactic HFNC or NIV (BiPAP) post-extubation reduces reintubation rates.
🗣️ Tracheostomy Speaking Valve (Passy-Muir)
⚠️ THE ONE RULE THAT CAN KILL: deflate the cuff first. The Passy-Muir Valve (PMV* (Passy-Muir Valve, the speaking valve)) is a one-way valve -air enters through the trach on inhalation, but the only exit on exhalation is up around the tube and out through the larynx, mouth, and nose. If the cuff is still inflated it blocks that exit, so air stacks with every breath → rising intrathoracic pressure → barotrauma and potentially fatal respiratory arrest. The cuff must be 100% deflated and a leak around the tube confirmed before the valve goes on. Never place a PMV on an inflated cuff.
How It Works
The PMV is a bias-closed, no-leak one-way valve that snaps onto the trach hub (with a quarter-turn) or sits in-line on the ventilator circuit. It is the only speaking valve that stays closed at rest: it opens on inhalation to let air in through the trach, then closes on exhalation and forces the exhaled breath up through the vocal folds and upper airway. That redirected, continuous column of air is what restores voice and subglottic pressure -the physiologic basis for nearly all of its benefits.
Other speaking valves are bias-open (open at rest). The PMV's closed-at-rest design is what re-establishes a continuous subglottic air column, which is why it tends to outperform on phonation and swallowing.
Indications & Benefits
Indication
Why it works
Restore voice / phonation
Exhaled air is forced through the larynx instead of out the trach, giving audible speech. The primary reason it is placed and the biggest quality-of-life and delirium-reducing win.
Improve swallowing, reduce aspiration
Closing on exhalation restores subglottic pressure and normal aerodigestive pressures, improving laryngeal sensation, cough strength, and airway protection.
Better secretion clearance & cough
Restored subglottic pressure produces a more effective, productive cough so secretions clear through the mouth rather than needing trach suction.
Restore smell & taste
Re-establishing nasal and oral airflow returns olfaction, and with it taste and appetite.
Facilitate weaning & decannulation
Reintroduces upper-airway airflow and reconditions a more physiologic breathing pattern, a step toward capping and tube removal.
Restore physiologic PEEP
The closed exhalation phase recreates the native end-expiratory pressure that is lost when the upper airway is bypassed.
Contraindications
Type
Contraindication
Why
ABSOLUTE
Inflated cuff
Blocks the only exhalation route → air stacking → barotrauma / fatal arrest. Must be fully deflated first.
ABSOLUTE
Foam-filled cuff (e.g., Bivona Fome-Cuf)
Self-inflates and cannot be reliably kept deflated, so the exhalation path can re-occlude. Same trapping risk.
ABSOLUTE
Total laryngectomy
No patent connection from trachea to upper airway -exhaled air has nowhere to go.
ABSOLUTE
Unconscious / comatose / unstable
Cannot protect the airway or signal distress, so the valve cannot be safely trialed.
CAUTION
Severe upper-airway obstruction (tracheal/subglottic stenosis, bilateral vocal-fold paralysis, large granulation, or trach tube too big for the airway)
Not enough room to exhale around the tube. Always do the leak check first; no leak means do not place.
CAUTION
Severe aspiration risk
Redirecting airflow does not fix a grossly unsafe swallow; assess before trialing.
Exhaling through the upper airway adds work of breathing the patient may not tolerate.
Not for endotracheal tubes. The PMV is a tracheostomy device only; it is never placed on an ETT.
Bedside Placement & Safety
1
Confirm candidacy -awake, stable, none of the absolute contraindications above.
2
Suction the trach and oral secretions (have suction ready -deflation often triggers a cough).
3
Deflate the cuff fully and slowly. 100% down, no exceptions. This is the step that prevents the lethal complication.
4
Confirm a leak around the tube -feel/listen for exhaled air at the mouth and nose, or watch the returned tidal volume drop on the vent. No leak = airway too obstructed → do NOT place.
5
Apply the valve (quarter-turn for a friction-tight fit). Coach: breathe in through the valve, voice on exhalation.
6
Monitor SpO₂, work of breathing, and comfort. Remove the valve immediately for rising work of breathing, desaturation, or distress -taking it off instantly restores the open exhalation path.
In-line on the ventilator: use the in-line valve (PMV 007, aqua), then adjust the vent for the cuff-deflation leak: reduce or remove set PEEP (the restored upper airway supplies physiologic PEEP, and added PEEP just escapes the open airway), increase set tidal volume to compensate for the leak, and silence/adjust the low-volume and low-pressure alarms (returned volume reads low by design, not from a circuit fault).
Pimp Questions
Why must the tracheostomy cuff be fully deflated before placing a Passy-Muir valve?
The PMV is a one-way valve: air enters through the trach on inhalation but can only exit up around the tube and out the upper airway on exhalation. An inflated cuff blocks that exit, so air stacks with every breath, intrathoracic pressure climbs, and the patient can suffer barotrauma or fatal respiratory arrest. The cuff must be 100% deflated and a leak confirmed before the valve goes on.
A patient is in distress and desaturating minutes after a PMV was placed. First move?
Remove the valve immediately. Distress after PMV placement means air cannot escape, usually an incompletely deflated cuff, upper-airway obstruction, or a trach tube too large for the airway. Taking the valve off instantly reopens the exhalation path through the trach. Then suction, re-check that the cuff is fully down, and evaluate for obstruction before any re-trial.
📋 On Rounds
On Rounds
Pimp Questions
What is driving pressure and why does it matter?
Driving pressure = Pplat − PEEP. It reflects the stress on functional lung units. A driving pressure > 15 cmH₂O is independently associated with increased ARDS mortality even when TV and Pplat are within targets. It may be the most important vent parameter to minimize.
What is auto-PEEP and when does it occur?
Air trapping due to incomplete exhalation before the next breath -common in COPD/asthma. Causes hemodynamic compromise (reduced venous return) and barotrauma. Detected by expiratory hold maneuver. Treated by reducing RR, increasing I:E ratio (longer expiratory time), and bronchodilators.
The vent is alarming with high peak pressures. How do you troubleshoot?
Peak pressure = airway resistance + compliance + PEEP. High peak + normal plateau (< 30) = airway resistance problem: bronchospasm (give albuterol), mucus plug (suction), kinked ETT, biting tube (bite block/sedation), small ETT. High peak + high plateau (> 30)
What is driving pressure and why is it more important than tidal volume alone?
Driving pressure = Plateau pressure − PEEP. It represents the actual distending pressure applied to the lung parenchyma. Goal: < 15 cmH₂O. A landmark meta-analysis by Amato (2015) showed driving pressure was the ventilator variable most strongly associated with survival in ARDS -more predictive than tidal volume or plateau pressure alone.
📋 Daily Vent Check Presentation
"Mr. Patel is intubated day 3 for hypoxemic respiratory failure from aspiration pneumonia. Current vent settings: AC/VC, TV 420 mL (6 mL/kg PBW), RR 18, PEEP 8, FiO₂ 0.55. This morning's ABG: pH 7.38, pCO₂ 42, pO₂ 74 -P/F ratio 135, consistent with moderate ARDS. Pplat is 24, driving pressure 16. He had a SAT trial this morning -he was following commands but became tachypneic. We are holding the SBT today and will reassess tomorrow. He is on propofol and fentanyl, RASS −1. Fluid balance is negative 200 mL over the past 24 hours."
Clinical Examples
Case 1: ARDS, Severe Pneumonia
Presentation: 45M admitted with severe bilateral pneumonia and hypoxemic respiratory failure. SpO₂ 82% on 15L NRB, intubated emergently. ABG post-intubation: pH 7.34, PaO₂ 70 on FiO₂ 0.8 → P/F ratio 88 (severe ARDS, <100).
Vent Strategy (ARDSNet): Mode AC/VC. PBW ~63 kg → TV 6 mL/kg PBW = 378 mL (set 380 mL). RR 18, PEEP 12, FiO₂ 0.8. Confirm Pplat after first breath: target <30 cmH₂O. Driving pressure (Pplat − PEEP) target <15 cmH₂O. ARMA, 2000
Escalation: P/F ratio persists <150 after 12–16h on optimized settings → initiate prone positioning for 16h/day. Consider neuromuscular blockade (Cisatracurium (Nimbex)) if severe patient-ventilator dyssynchrony. Repeat ABG 30 min after every vent change.
Teaching point: Always use PBW (predicted body weight, from height and sex), not actual body weight, for TV calculation. Over-ventilating causes ventilator-induced lung injury (VILI) and increases mortality, even a few extra mL/kg matters.
Case 2: COPD Exacerbation, Auto-PEEP Risk
Presentation: 68F with severe AECOPD, on BiPAP for 4h with worsening hypercapnia (pH 7.18, pCO₂ 92). BiPAP failure → intubated with RSI using Ketamine (Ketalar) + Succinylcholine (Anectine).
Vent Strategy: Mode AC/VC. TV 6–8 mL/kg PBW. RR 12–14/min (low rate = more time to exhale). High inspiratory flow rate (60–80 L/min) to shorten inspiratory time. Target I:E ratio 1:4 (vs. normal 1:2) to maximize expiratory time and prevent breath stacking. Start PEEP 5.
Auto-PEEP check: Perform end-expiratory hold maneuver, press hold, read auto-PEEP off the ventilator display. Auto-PEEP >5 cmH₂O = air trapping. Treatment: decrease RR, increase expiratory time, aggressive bronchodilators (Albuterol + Ipratropium); if critical, briefly disconnect ETT and allow full passive exhalation.
Permissive hypercapnia: Target pH 7.25–7.35, not a normal pCO₂. Do not raise RR to normalize CO₂, this worsens air trapping. Hemodynamic stability is the goal, not a normal ABG.
Case 3: Ventilator Weaning, SAT + SBT Protocol
Presentation: 55M intubated day 5 for Category E PE with hemodynamic instability, now improving. On AC/VC, RR 14, TV 450 mL, PEEP 5, FiO₂ 0.35. SpO₂ 96%, hemodynamically stable, off vasopressors. RASS −1, follows commands, intact cough.
Step 1, SAT (Sedation Vacation): Hold Propofol and Fentanyl infusions every morning. Assess within 30 min: opens eyes to voice, follows commands, breathing comfortably? Fail criteria: agitation, RR >35, SpO₂ <88%, hemodynamic instability → restart sedation at half dose. Girard, 2008
Step 2, SBT (Spontaneous Breathing Trial): SAT passes → switch to PS 5 / PEEP 5 for 30–120 min. Readiness: FiO₂ ≤40%, PEEP ≤8, hemodynamically stable. Pass criteria: RR <35, SpO₂ >90%, no significant accessory muscle use, RSBI (f/VT in L) <105. Example: RR 18, TV 0.45L → RSBI = 40 → pass.
Decision: Passes both SAT + SBT → proceed to extubation. Fails repeatedly (≥3 attempts over multiple days) → discuss tracheostomy to facilitate long-term weaning, reduce dead space, and improve patient comfort.
Assess readiness: FiO2 ≤ 40%, PEEP ≤ 8, hemodynamically stable, no high-dose vasopressors, adequate mental status. RSBI < 105 (RR/TV in liters) predicts successful extubation. Girard, 2008: paired SAT + SBT improves outcomes.
Plateau pressure
q4–6h or with vent changes
Pplat < 30 cmH2O (lung protective). If exceeding → reduce TV, check for pneumothorax, bronchospasm, or mucus plugging.
Driving pressure
q4–6h
Driving pressure < 15 cmH2O (Pplat - PEEP). Strongest predictor of ARDS mortality Amato, 2015. Optimize by adjusting TV and PEEP.
SpO2 / FiO2 trending
Continuous SpO2, track P/F ratio
SpO2 target 88–95% in ARDS, 94–98% otherwise. Worsening P/F may indicate disease progression, fluid overload, or new complication.
Auto-PEEP check
q shift and with clinical concern
Expiratory hold maneuver. Auto-PEEP > 5 = air trapping → increase expiratory time (decrease RR, decrease I:E ratio). Common in COPD/asthma.
Sedation level (RASS)
q4h
Target RASS -2 to 0 (light sedation). Deeper sedation only if specific indication (prone, paralysis, severe agitation). Daily sedation awakening trial (SAT).
Daily SAT + SBT
Every morning
Girard, 2008: paired protocol -SAT first (hold sedation, assess arousal) → if passes → SBT (PS 5–8/PEEP 5 for 30–120 min). Reduces vent days and mortality.
VAE surveillance
Daily
Ventilator-associated events: new/worsening infiltrate, rising FiO2/PEEP after period of stability, fever, purulent secretions. Prevent with: HOB 30-45°, oral care, DVT/PUD prophylaxis, daily SBT.
Every vent day is a bad day. The single best thing you can do for a ventilated patient is liberate them from the ventilator. Daily SAT + SBT is the most evidence-based strategy to shorten ventilator duration.
⚡ Summary
Summary
Escalate in Order
Nasal cannula (up to 6 L) → venturi mask → non-rebreather → high-flow nasal cannula → NIV → intubation.High-flow nasal cannula is not just more oxygen: it washes out nasopharyngeal dead space and delivers a few cmH₂O of PEEP, which is why it works in hypoxemic failure where a non-rebreather has stopped working.
CPAP or BiPAP
CPAP is one continuous pressure and fixes oxygenation, so it is the choice in cardiogenic pulmonary edema, where it also cuts preload and afterload. BiPAP adds an inspiratory boost above the expiratory pressure, and that difference is the tidal volume, so it is what fixes ventilation in a hypercapnic COPD exacerbation. NIV in COPD and cardiogenic edema reduces intubation and mortality; it is far weaker evidence in pneumonia and ARDS.
Four Reasons to Intubate
Failure to protect the airway, failure to oxygenate, failure to ventilate, and anticipated clinical course. The fourth is the one that gets under-called: a patient who is predictably deteriorating is safer intubated now, in daylight with a full team, than at 3 am as a crash airway.
The Two Knobs
Oxygenation is FiO₂ and PEEP. Ventilation is respiratory rate and tidal volume. A low saturation means turn up PEEP or FiO₂; a high CO₂ means increase minute ventilation. Confusing the two is the commonest ventilator error, and raising the rate for a hypoxemic patient just causes breath stacking.
Starting Settings
Volume control, tidal volume 6 to 8 mL/kg of predicted (not actual) body weight, rate 12 to 16, PEEP 5, FiO₂ 100% then wean down quickly.Predicted body weight is calculated from height, because lung size tracks height, not weight: dosing a 6-foot obese patient on actual weight delivers a frankly injurious volume.
Watch Plateau Pressure, Not Peak
Keep plateau pressure below 30 cmH₂O and driving pressure below 15.A high peak with a normal plateau is an airway problem (secretions, bronchospasm, a kinked or biting tube); a high peak with a high plateau is a lung or chest wall compliance problem (pulmonary edema, ARDS, pneumothorax, abdominal distension). The measurement takes an inspiratory hold and it tells you which of those two you are dealing with.
Sudden Deterioration: Think DOPE
Displaced tube, Obstruction, Pneumothorax, Equipment failure. Disconnect from the ventilator and bag by hand: easy bagging points to the machine, difficult bagging points to the patient, and this single maneuver also relieves the breath stacking that causes hypotension in obstructive disease.
Wean With a Daily SBT
Screen daily and pair a spontaneous awakening trial with a spontaneous breathing trial, which reduces ventilator days and mortality. Rapid shallow breathing index below 105 predicts success.Passing an SBT is not enough on its own: the patient still needs to protect the airway and manage their secretions, and a cuff leak test is worth doing where laryngeal edema is a risk.
RoundsRx Infographic Series · #3 · Respiratory · PDF 153 KB
Text version
ICU · Ventilator · One Pager
Mechanical Ventilation
Know your numbers every morning. When in doubt -disconnect and bag. DOPE for acute deterioration. SAT + SBT daily to get them off the vent.
⚙️ Initial Settings
ModeAC/VC (most common)
Tidal volume6–8 mL/kg PBW
Rate14–16 /min
FiO₂1.0 → wean to SpO₂ 94–98%
PEEP5 cmH₂O (start)
🆘 Acute Deterioration -DOPE
D -Displacement (ETT too deep/dislodged)
O -Obstruction (mucus plug, biting)
P -Pneumothorax → needle decompress
E -Equipment failure → bag the patient
📊 Pressure Interpretation
High Peak, Normal Plat: Airway resistance → suction, bronchodilator
High Peak + High Plat: Compliance problem → PTX, ARDS, edema
Driving pressure = Pplat − PEEP. Target ≤ 15.
✅ Weaning -Daily SAT + SBT Girard 2008
Stop sedation daily (SAT)
SBT on CPAP 5 / PS 5–8 for 30–120 min
RSBI < 105 = ready to extubate
Pass both → extubate
📣 Sample Presentation
One-Liner
"Mr. Brown is a 64-year-old intubated for COPD exacerbation with hypercapnic respiratory failure. Currently on AC/VC: TV 450, RR 16, PEEP 5, FiO₂ 30%. Morning ABG: pH 7.38, pCO₂ 52, pO₂ 88."
Key Points to Cover on Rounds
Intubation indication: hypercapnic respiratory failure (pH 7.22, pCO₂ 78 on presentation, failed BiPAP). Current ABG improved: pH 7.38, pCO₂ 52 (his baseline is ~48). Vent: AC/VC, TV 450 mL (6 mL/kg), RR 16, PEEP 5, FiO₂ 30%. Plateau 22, no auto-PEEP. Sedation: propofol off, RASS 0, following commands. SAT passed, SBT with PSV 5/5 × 30 min -RR 18, TV 380, no distress. Plan: extubate today. BiPAP standby. Nebs q4h.
Cardiac pump failure causing inadequate tissue perfusion. Cold, clammy, hypotensive with elevated filling pressures. In-hospital mortality 40–50%. Identify and reverse the cause -fast.
🔍 Overview
Definition & Criteria
Cardiogenic shock = cardiac pump failure resulting in tissue hypoperfusion. Classic hemodynamic criteria: SBP < 90 mmHg for > 30 min (or vasopressor requirement), CI < 2.2 L/min/m², PCWP > 15 mmHg.
Causes
Cause
Key Features
Acute MI / ACS (~70–80%)
Most common cause. Large anterior STEMI, RV infarct. Emergent PCI/cath lab. SHOCK trial: early revascularization ↓ 6-month mortality SHOCK, 1999.
Acute decompensated HFrEF (~10–15%)
End-stage HF on maximal GDMT. Progressive pump failure. Bridge to LVAD/transplant or palliative.
Acute valvular emergency (~5–8%)
Acute severe MR (papillary muscle rupture post-MI), acute AR (endocarditis, aortic dissection), critical AS. Emergent surgical consult.
Fulminant myocarditis (~2–5%)
Viral (Coxsackie, parvovirus B19), giant cell, eosinophilic. Young patient, rapid-onset HF. MRI if stable, biopsy if refractory. May need mechanical circulatory support (MCS) bridge to recovery.
Category E PE (~2–3%)
RV failure from acute pressure overload. Not true "pump" failure -it's obstructive. tPA, catheter-directed therapy, or surgical embolectomy.
Troponin, BNP -confirm myocardial injury, severity of HF
ABG -lactate, acid-base (metabolic acidosis = bad sign)
BMP -creatinine, K⁺, glucose
CXR -pulmonary edema, cardiomegaly
Invasive monitoring (PA catheter / arterial line) -if diagnosis uncertain or refractory to treatment
Hemodynamic Profiles by PA Catheter
Shock Type
CO
SVR
PCWP
Cardiogenic
↓↓
↑↑
↑↑
Distributive (Septic)
↑ or normal
↓↓
Low/normal
Hypovolemic
↓
↑
↓↓
Obstructive (PE/Tamponade)
↓
↑
Variable
🚨 Management
Management
Immediate
ABCs, ICU transfer, arterial line, central line. Cardiac monitoring. Call cardiology immediately. If STEMI -activate cath lab NOW (door-to-balloon < 90 min). Do NOT delay revascularization for hemodynamic stabilization.
Vasopressors (MAP target ≥ 65)
Norepinephrine first-line for vasopressor support. Do NOT use dopamine (increased arrhythmias in SHOCK trial). Add vasopressin or epinephrine for refractory hypotension.
Inotropes (for low CO)
Dobutamine 2–20 mcg/kg/min -increases CO, reduces afterload. Use when MAP is adequate but CO is still low (cold, not adequately responding to pressors alone). Can cause hypotension and tachyarrhythmias.
Revascularization (if ACS)
Emergency PCISHOCK 1999: early revascularization reduces 1-year mortality in cardiogenic shock from MI. Do not delay for stabilization. Surgical revascularization if anatomy unsuitable for PCI.
Mechanical Circulatory Support
IABP (intra-aortic balloon pump) -no mortality benefit IABP-SHOCK II 2012. Impella or ECMO for refractory CS. Consider early in rapidly deteriorating patients -get mechanical circulatory support (MCS) team involved before the patient is "too sick."
Treat the Cause
Tamponade → pericardiocentesis. Acute severe MR/VSD → surgery. Fulminant myocarditis → steroids + mechanical circulatory support (MCS) bridge. Complete heart block → temporary pacing. Identify and reverse.
💊 Medications & Doses
Medications
Drug
Dose
Role
Notes
Norepinephrine (Levophed) 1ST LINE
0.1–1 mcg/kg/min
First-line vasopressor
Preferred over dopamine in CS. Increases MAP without excessive tachycardia.
Dobutamine (Dobutrex)
2–20 mcg/kg/min
Inotrope
↑CO, ↓SVR. Use when MAP adequate but CO still low. Titrate to clinical response. Can cause arrhythmias.
Milrinone (Primacor)
0.375–0.75 mcg/kg/min
Inotrope/vasodilator
PDE3 inhibitor. Good in chronic HF (not beta-blocked). Avoid if hypotensive (vasodilatory). Renally cleared.
Vasopressin (Pitressin)
0.03–0.04 units/min
Vasopressor add-on
Nonadrenergic -useful adjunct to reduce catecholamine dose. Fixed dose.
Aspirin + Heparin
325 mg PO + UFH per ACS protocol
ACS-associated CS
Antiplatelet + anticoagulation for PCI. Do not hold for hemodynamic instability.
📋 On Rounds
On Rounds
Pimp Questions
Why is dopamine avoided in cardiogenic shock?
SOAP II, 2010 and SHOCK trial subgroup: dopamine causes significantly more arrhythmias (especially atrial fibrillation) compared to norepinephrine in cardiogenic and other shock states, without mortality benefit. Norepinephrine is safer and equally effective.
What did the IABP-SHOCK II trial show?
IABP-SHOCK II 2012: Intra-aortic balloon pump did NOT reduce 30-day mortality in cardiogenic shock complicating MI compared to medical therapy alone. This changed practice -IABP is no longer routinely recommended for CS despite being widely used before this trial.
How do you differentiate cardiogenic shock from septic shock at the bedside?
A patient with cardiogenic shock has MAP 62 on norepinephrine but cardiac index is 1.4. What do you add?
Add an inotrope -dobutamine or milrinone. The MAP is adequate (≥65) but cardiac output is critically low (CI < 2.2). Norepinephrine raises MAP via vasoconstriction but doesn't improve forward flow. Dobutamine (β₁ > β₂): increases contractility and CO, first-line inotrope. Start 2.5 mcg/kg/min, titrate to CI > 2.2. Risk: tachycardia, hypotension from β₂ vasodilation.
What is an Impella and how does it differ from IABP and ECMO?
Impella: percutaneous axial flow pump placed across the aortic valve (femoral artery → LV). Actively pumps blood from LV into aorta. Provides 2.5-5.5 L/min support depending on device. Unloads the LV (reduces wall stress, O₂ demand). IABP: inflates in diastole (augments coronary perfusion), deflates in systole (reduces afterload). Only provides ~0.5 L/min augmentation -modest hemodynamic support. No mortality benefit IABP-SHOCK II, 2012.
Why does VA-ECMO increase LV afterload, and why is that dangerous?
VA-ECMO returns oxygenated blood into the femoral artery → flows retrograde into the aorta → increases aortic pressure against which the LV must eject. If the LV is too weak to open the aortic valve against this increased pressure, the LV becomes a stagnant, distended chamber → LV distension → increased wall stress → increased O₂ demand → worsening ischemia → pulmonary edema (blood backs up into lungs).
What is the SCAI classification of cardiogenic shock and why does it matter?
SCAI shock classification (Society for Cardiovascular Angiography and Interventions) stages A through E: A = At risk (large MI, no shock), B = Beginning (hypotension or tachycardia, but adequate perfusion), C = Classic (hypoperfusion requiring intervention -pressors or MCS), D = Deteriorating (failing initial therapy, escalating support), E = Extremis (refractory shock, CPR, multiple pressors at max).
A patient has an acute massive MI with cardiogenic shock. Should you stabilize hemodynamics before taking them to the cath lab?
NO -do NOT delay revascularization to "stabilize" the patient. The SHOCK, 1999 trial showed that early revascularization (PCI or CABG within 6h) reduced 6-month mortality from 63% to 50% compared to initial medical stabilization. The myocardium is dying -every minute of delay = more infarct → worse pump function → deeper shock. Start pressors and inotropes while preparing for cath, not instead of cath.
What are the mechanical complications of MI that cause cardiogenic shock, and how do you diagnose them?
Three mechanical complications (typically 3-7 days post-MI): (1) Ventricular septal rupture (VSR): new harsh holosystolic murmur + step-up in O₂ sat from RA to PA on PA catheter. Echo: VSD with L→R shunt. Treatment: surgical repair (emergent). (2) Papillary muscle rupture: new severe MR (holosystolic murmur at apex, but may be soft if severe). PA catheter: large V waves on PCWP tracing. Echo: flail mitral leaflet.
How do you use a PA catheter to guide management in cardiogenic shock?
PA catheter (Swan-Ganz) gives 4 key hemodynamic parameters: (1) CI (cardiac index): < 2.2 = cardiogenic shock. Target > 2.2 with inotropes. (2) PCWP: > 15 = volume overloaded / high filling pressures. Guide diuresis or vasodilator therapy. (3) SVR: elevated in cardiogenic shock (compensatory vasoconstriction). If very high (> 1,800) → afterload reduction may improve forward flow
Clinical Examples
📋 Case 1, Anterior STEMI with Cardiogenic Shock
Patient: 59M, PMH HTN, smoking. Crushing chest pain x2h. ECG: ST elevation V1-V5. BP 78/50, HR 110, cold/clammy, JVP elevated.
Key findings: Lactate 5.8, troponin > 50, BNP 1200. Echo: anterior wall akinesis, EF ~15%. Cardiogenic shock from anterior STEMI.
Management:
Emergent cardiac cath, do NOT delay for stabilization SHOCK, 1999
Norepinephrine first-line, NOT dopamine SOAP II, 2010
Dobutamine 2-20 mcg/kg/min if MAP adequate but CI < 2.2
Activate MCS team early for Impella consideration
Aspirin 325 mg + heparin per ACS protocol
Teaching point: The cath lab IS the treatment for MI-related CS. Every minute of delay = more infarct = deeper shock. Start pressors while preparing for PCI, not instead of PCI.
📋 Case 2, Mechanical Complication Post-MI
Patient: 72F, POD 5 from inferior STEMI. Sudden hypotension (BP 65/40), new loud holosystolic murmur at LLSB, acute respiratory distress.
Key findings: Echo: VSD with L-to-R shunt. PA catheter: O2 sat step-up from RA to RV. CI 1.6, PCWP 24.
Management:
Norepinephrine for MAP support
IABP for temporary support (reduces afterload, decreases L-to-R shunt)
Emergent cardiac surgery, surgical VSD repair is definitive
Nitroprusside if MAP tolerates (reduces shunt fraction)
Teaching point: Mechanical complications (VSD, papillary muscle rupture, free wall rupture) occur 3-7 days post-MI. Any acute deterioration in this window requires immediate echo. New murmur post-MI = VSD or acute MR until proven otherwise.
📋 Case 3, Refractory CS Requiring VA-ECMO
Patient: 45M with fulminant myocarditis. EF 5%, SCAI stage D. On max NE + dobutamine + vasopressin. Lactate rising 6 to 12.
Add Impella for LV venting (ECPELLA), ECMO increases LV afterload
Monitor for LV distension (aortic valve not opening = inadequate venting)
Endomyocardial biopsy; empiric steroids if giant cell myocarditis suspected
Transplant evaluation
Teaching point: VA-ECMO provides support but increases LV afterload. Without LV venting, the LV distends, worsening ischemia and pulmonary edema. IABP provides insufficient support IABP-SHOCK II, 2012.
📋 Sample Presentation
"Mr. Kim is a 61-year-old with no known cardiac history who presented with anterior STEMI complicated by cardiogenic shock. He underwent emergency PCI with stenting of the LAD. Echo post-cath shows EF of 20% with anterior wall akinesis. He was started on norepinephrine and dobutamine in the cath lab. He is on NE 0.3 mcg/kg/min and dobutamine 10 mcg/kg/min. This morning his MAP is 67, lactate trending down from 6.2 to 3.1, UO 40 mL/hr. He remains intubated. We are in contact with our mechanical circulatory support (MCS) team regarding Impella consideration given refractory shock. Cardiology and cardiac surgery are both following."
⚡ Summary
Summary
Recognize the Profile
Cold and wet: hypotension with poor perfusion and elevated filling pressures. Cool extremities, mottling, narrow pulse pressure, oliguria, rising lactate, altered mentation. In-hospital mortality is 40 to 50%, and the trajectory is set in the first hours.
Get the Echo Immediately
It is the most important early test: it confirms the diagnosis, identifies the cause and directs management, all at the bedside. Look specifically for a mechanical complication, acute mitral regurgitation, ventricular septal rupture, tamponade or RV failure, because each of those changes the plan completely.
Most of It Is Acute MI
ACS causes 70 to 80%, typically a large anterior STEMI or an RV infarct. Emergent revascularization is the intervention that changes mortality (SHOCK trial), so the cath lab is activated at the same time the vasopressor is started, not after stabilization. Decompensated HFrEF accounts for another 10 to 15%.
Norepinephrine Is the First Vasopressor
It beat dopamine in cardiogenic shock, with fewer arrhythmias and lower mortality in that subgroup (De Backer). Restore perfusion pressure first, then add an inotrope, dobutamine or milrinone, once the mean arterial pressure will tolerate the vasodilation they cause. Milrinone is renally cleared and long-acting, so it is harder to back out of in renal failure.
Do Not Give the Usual Heart Failure Drugs
Beta blockers, ACE inhibitors and ARBs are held in shock: this patient needs inotropy and perfusion pressure, not afterload reduction and negative inotropy. Diuretics do not work until cardiac output is restored, and giving them into a low-output state worsens the kidney. Resume guideline therapy once the patient is off support.
Get the Volume Status Right in Both Directions
Not every cardiogenic shock patient is wet.RV infarct is preload-dependent and needs fluid, and nitrates or diuretics there cause profound hypotension. Use the echo, the JVP and the response to a small challenge rather than assuming. A pulmonary artery catheter is back in favor for defining the hemodynamic profile when the picture is unclear.
Escalate Mechanically Before the Organs Fail
Intra-aortic balloon pump did not improve mortality in IABP-SHOCK II, so it is not the reflex it once was. Impella or VA-ECMO for refractory shock, decided early by a shock team, since salvage after multiorgan failure is poor. Frame it explicitly as a bridge: to recovery, to transplant, or to a durable device, and confirm which before cannulating.
Track Perfusion, Not Blood Pressure
Lactate clearance, mentation, urine output and mixed venous saturation tell you whether the organs are being perfused; a mean arterial pressure propped up by escalating vasopressors does not. A rising lactate on rising support means the strategy has failed and it is time for mechanical support or a goals-of-care conversation, not another dose increase.
RoundsRx Infographic Series · #50 · Cardiovascular · PDF 153 KB
Text version
ICU · Cardiology · One Pager
Cardiogenic Shock
Cold, clammy, low output with elevated filling pressures. Mortality 40–50%. Treat the cause fast. NE first, NOT dopamine. Early mechanical circulatory support (MCS) if refractory.
❤️ Definition & Causes
SBP < 90 + CI < 2.2 + PCWP > 15
Acute MI (large anterior STEMI)
Acute valvular emergency
Fulminant myocarditis
Category E PE / tamponade
🔍 Key Workup
ECG immediately -activate cath lab if STEMI
Echo -EF, wall motion, tamponade, RV
Troponin, BNP, ABG, lactate
PA catheter if diagnosis unclear
🚨 Management
1
ICU, art line + central line. Call cardiology immediately. Do NOT delay PCI for "stabilization."
2
Norepinephrine (NOT dopamine SOAP II, 2010) for MAP ≥ 65. Add vasopressin if refractory.
3
Dobutamine 2–20 mcg/kg/min if MAP adequate but CO still low.
BP usually > 180/120 with acute end-organ damage. The organ being damaged determines the drug and the target. Do NOT drop BP too fast -cerebral autoregulation cannot keep up.
🔍 Overview
Hypertensive Emergency vs Urgency
Emergency: Severely elevated BP + acute end-organ damage. Requires IV therapy, ICU admission, controlled BP reduction.
Urgency: Severely elevated BP without end-organ damage. Can be managed with oral agents and close outpatient follow-up. NOT an emergency. Outpatient target: SBP <130 for high-risk patients SPRINT, 2015. First-line: thiazide-type diuretic ALLHAT, 2002.
Aortic Dissection must be excluded first if BP very high + chest/back pain. Different drugs, different targets. CTA chest/abdomen/pelvis immediately. Do NOT give nitroprusside until dissection excluded.
🚨 Management
BP Reduction Targets -By Syndrome
General Rule: Reduce MAP by no more than 25% in the first hour, then to 160/100 over the next 2–6 hours. Exception: aortic dissection (aggressive), ischemic stroke (conservative).
Syndrome
Target
First-Line Drug
Hypertensive encephalopathy
MAP reduction 20–25% in 1h
Nicardipine or labetalol IV
Aortic dissection (Type A/B)
SBP < 120, HR < 60 ASAP
Esmolol + nitroprusside or nicardipine
Acute pulmonary edema
Rapid reduction
Nicardipine + nitroglycerin IV + diuresis
ACS with hypertension
SBP < 140
Nitroglycerin IV + beta-blocker
Ischemic stroke
Only treat if BP > 220/120 (no tPA) or > 185/110 (if tPA candidate) AHA/ASA, 2019
Labetalol or nicardipine IV -go slow
Hemorrhagic stroke
SBP < 140 ATACH-2, 2016INTERACT2, 2013
Nicardipine or labetalol IV
Eclampsia
SBP < 160, DBP < 110
Labetalol IV or hydralazine IV + MgSO₄ MAGPIE, 2002
Pheochromocytoma crisis
MAP reduction 20–25%
Phentolamine IV -α-blockade first, then add beta-blocker
Never use beta-blockers alone in pheochromocytoma. Unopposed α stimulation → paradoxical hypertensive crisis. Always α-block first.
This is a hypertensive EMERGENCY (not urgency) -end-organ damage present: AKI, proteinuria with active sediment (renal), troponin elevation (cardiac), visual changes (retinal/CNS).
Step 1 -Choose IV agent based on end-organ damage:
Renal damage → Nicardipine (Cardene) 5mg/hr IV, titrate by 2.5mg/hr q5-15min (max 15mg/hr). Smooth, titratable, no renal dosing needed.
Aortic dissection → Esmolol (Brevibloc) drip first (target HR <60), THEN add nicardipine. Must reduce HR before afterload reduction.
Eclampsia → Magnesium sulfate + hydralazine (Apresoline) or labetalol (Trandate).
Stroke → see specific stroke BP targets (different for ischemic vs hemorrhagic, tPA vs no tPA).
Step 2 -BP target:
Reduce MAP by no more than 25% in the first hour. Then toward 160/100 over next 2-6 hours.
Do NOT normalize BP rapidly → risk of watershed infarction (brain, kidneys).
Exception: Aortic dissection → SBP <120 within 20 minutes.
Step 3 -Transition to oral:
Once stable on IV × 12-24h → start oral antihypertensive (amlodipine 5-10mg, lisinopril, etc.).
Overlap IV + PO for 2-4 hours before weaning drip.
Hypertensive URGENCY (BP >180/120 WITHOUT end-organ damage): Do NOT use IV meds. Restart/uptitrate oral meds. Discharge with close follow-up. The BP did not get this high overnight and does not need to come down overnight.
📋 Case 2, Hypertensive Emergency with Acute Aortic Dissection
Patient: 58M with sudden tearing chest pain radiating to back. BP 210/120. CT angiography: Stanford Type B dissection.
Step 1 -IV esmolol drip FIRST: Target HR <60 BEFORE lowering BP. Beta-blocker first to reduce aortic shear stress. Do NOT lower BP without HR control first, dropping BP alone causes reflex tachycardia → increased aortic shear → propagation of dissection.
Step 2 -Add vasodilator AFTER HR controlled: Nicardipine or nitroprusside for BP target <120 systolic within 20 minutes. Never nitroprusside alone, must have beta-blocker on board first.
Step 3 -Pain control: IV morphine. Pain drives catecholamine release → higher BP. Adequate analgesia is part of BP management.
Type A (ascending) → emergent surgery. Type B (descending) → medical management unless complicated (malperfusion, rupture, refractory pain).
Key Lesson: In dissection, HR control comes BEFORE BP control. Esmolol first, then vasodilator. Target SBP <120 and HR <60. Never nitroprusside alone.
📋 Case 3, Hypertensive Emergency with Acute Pulmonary Edema
Patient: 72F with flash pulmonary edema, BP 230/130, SpO2 82%, severe respiratory distress.
Step 1 -Position + BiPAP immediately: Sit upright. BiPAP reduces preload + afterload + improves oxygenation. Start before anything else.
Step 2 -IV nitroglycerin drip: Start 5 mcg/min, titrate rapidly up to 200 mcg/min if needed. Potent vasodilator that reduces both preload AND afterload. Nitroglycerin is MORE important than diuresis in the first 30 minutes.
Step 3 -IV furosemide 80-120mg: Important but secondary to nitroglycerin. The acute crisis is afterload-driven, not volume-driven (though volume contributes).
Do NOT give labetalol, negative inotropy worsens acute decompensated heart failure. Avoid beta-blockers in this setting.
BP target: Reduce by 25% in the first hour. Reassess with repeat CXR, SpO2 trending, work of breathing.
Key Lesson: Flash pulmonary edema = BiPAP + nitroglycerin drip. Nitroglycerin is the hero, not lasix. Avoid beta-blockers in acute decompensated HF.
💊 Medications & Doses
IV Antihypertensive Agents
Drug
Dose
Onset
Best For
Avoid In
Nicardipine (Cardene)
5–15 mg/hr IV drip
5–10 min
Most hypertensive emergencies. Excellent titratable agent.
The workup answers ONE question: Is there end-organ damage? YES → hypertensive emergency (IV meds, ICU). NO → hypertensive urgency (oral meds, outpatient). The BP number alone does NOT define the emergency.
Test
Looking For
End-Organ Damage
BMP + Cr
Cr above baseline
Renal: AKI from malignant nephrosclerosis
UA + microscopy
Proteinuria, hematuria, RBC casts
Renal: Active sediment = hypertensive nephropathy
Troponin
Elevated, rise-fall
Cardiac: Demand ischemia or ACS from afterload
ECG
LVH, ST/T changes, new arrhythmia
Cardiac: Acute ischemia, atrial strain
CXR
Pulmonary edema, wide mediastinum
Cardiac: Flash pulmonary edema. Wide mediastinum → CTA for dissection
Fundoscopy
Flame hemorrhages, papilledema
Retinal/CNS: Grade III-IV = malignant HTN
CT head
Hemorrhage, PRES, ischemia
CNS: Order if headache, AMS, focal deficits, seizures, visual changes
Peripheral smear
Schistocytes, low platelets
Hematologic: MAHA from shear stress. Check LDH ↑, haptoglobin ↓
BNP
Elevated
Cardiac: Flash pulmonary edema from afterload crisis
Urine drug screen
Cocaine, amphetamines
Etiology: Avoid beta-blockers with cocaine (unopposed alpha)
Emergency vs Urgency: Emergency = elevated BP + end-organ damage → IV meds, ICU, reduce MAP 25% in first hour. Urgency = elevated BP WITHOUT damage → oral meds, discharge with follow-up 24-72h. Do NOT use IV meds for urgency.
📋 On Rounds
On Rounds
Pimp Questions
Why should you not lower BP too fast in hypertensive emergency?
Chronic hypertension shifts the cerebral autoregulation curve rightward. These patients need higher perfusion pressures to maintain cerebral blood flow. Rapid BP reduction causes cerebral ischemia -watershed infarcts, blindness (anterior ischemic optic neuropathy), renal infarction. Max 25% MAP reduction in first hour.
What is the BP target for ischemic stroke and why is it different?
Only treat if BP > 220/120 (no tPA) because elevated BP in ischemic stroke maintains perfusion to the ischemic penumbra. Lowering BP aggressively expands the infarct. Exception: if patient is a tPA candidate, reduce to < 185/110 first to reduce hemorrhage risk.
Why do you target only 25% MAP reduction in the first hour instead of normalizing BP?
Cerebral autoregulation is shifted right in chronic hypertension. The brain has adapted to higher pressures -the autoregulatory curve (which maintains constant cerebral blood flow across a range of MAPs) shifts upward. If you drop BP too quickly to "normal" levels, you fall below the lower limit of autoregulation → cerebral hypoperfusion → watershed stroke.
What IV antihypertensive do you choose for different end-organ emergencies?
Match the drug to the complication: Nicardipine (DHP CCB drip): best all-purpose -works for most emergencies. Smooth, titratable, no CNS depression. Clevidipine: ultra-short acting CCB -good when minute-to-minute control needed. Labetalol: combined α/β blocker -good for aortic dissection (reduces HR + BP), preeclampsia (safe in pregnancy). Esmolol: ultra-short BB -best for dissection when you need rapid HR < 60.
Clinical Examples
📋 Case 1, Hypertensive Emergency with Acute Kidney Injury
Patient: 54M, non-adherent to amlodipine and lisinopril, presents with headache, blurred vision, and nausea. No chest pain or focal neurologic deficits.
Key findings: BP 238/142, HR 92. Fundoscopy: flame hemorrhages + papilledema. Cr 3.4 (baseline 1.2), proteinuria 3+, hematuria. CT head negative. TTE: LVH, EF 55%.
Management:
IV nicardipine drip starting at 5 mg/hr, titrate q5-15 min (max 15 mg/hr)
Target: reduce MAP by 25% in first hour, then to 160/100 over next 2-6h
Arterial line for continuous BP monitoring
Trending Cr q12h, expect improvement with controlled BP reduction
Transition to oral amlodipine 10 mg + lisinopril 20 mg when stable on drip x 24h
Teaching point: Hypertensive nephrosclerosis with acute end-organ damage (AKI + papilledema) defines hypertensive emergency. Nicardipine is first-line for most hypertensive emergencies: smooth, titratable, no CNS depression. Renal function often improves with controlled BP reduction.
📋 Case 2, Hypertensive Emergency in Acute Ischemic Stroke
Patient: 72F, HTN and AF (not on anticoagulation), presents with acute right-sided weakness and aphasia. Symptom onset 2 hours ago. NIHSS 14.
Key findings: BP 204/118, HR 88 irregular. CT head: no hemorrhage. CTA: left MCA occlusion. tPA candidate (within window, no contraindications).
Management:
BP must be < 185/110 BEFORE tPA administration
IV labetalol 10-20 mg bolus; repeat if needed. Alternatively, nicardipine drip
Once tPA given: maintain BP < 180/105 for 24 hours
If NOT a tPA candidate: only treat BP if > 220/120 (permissive hypertension protects the penumbra)
Thrombectomy evaluation given large vessel occlusion
Teaching point: BP management in stroke differs from other hypertensive emergencies. Aggressive BP lowering in ischemic stroke expands the infarct by reducing perfusion to the penumbra. The only reason to lower BP acutely is to safely give tPA. AHA/ASA Stroke Guidelines, 2019
📋 Case 3, Pheochromocytoma Crisis
Patient: 42F, no prior medical history, presents with episodic severe headaches, palpitations, and diaphoresis. In the ED, BP spikes to 260/150 with HR 132 during a paroxysm.
Key findings: Between episodes: BP 145/90. 24h urine metanephrines: 4x upper normal. CT abdomen: 4.2 cm right adrenal mass. Plasma-free metanephrines markedly elevated.
Management:
Phentolamine 5 mg IV bolus for acute crisis (alpha-blocker)
Start phenoxybenzamine 10 mg BID, titrate up over 10-14 days pre-operatively
Add beta-blocker (propranolol) ONLY AFTER adequate alpha blockade (typically 3-5 days later)
NEVER give beta-blocker first, causes unopposed alpha stimulation and hypertensive crisis
High-sodium diet + liberal fluids to restore intravascular volume before surgery
Teaching point: Pheochromocytoma hypertensive crisis requires alpha-blockade FIRST. Beta-blockers before alpha-blockade removes the beta-2 vasodilatory counterbalance, leaving unopposed alpha vasoconstriction. This is one of the most testable concepts in medicine.
📋 Sample Presentation
"Mrs. Okafor is a 58-year-old with poorly controlled hypertension who presented with BP 210/130, severe headache, and confusion. She was found to have papilledema on fundoscopy and elevated creatinine of 2.8 from a baseline of 1.0, consistent with hypertensive emergency with end-organ damage involving the CNS and kidneys. CT head showed no hemorrhage. She was started on nicardipine drip and MAP was reduced by 22% over the first hour to 147. She is now alert, BP 158/96 on nicardipine 8 mg/hr. Plan is to continue gradual reduction to target BP 150/90 over the next 24–48 hours, then transition to oral agents."
Monitoring Parameters -Hypertensive Emergency
Parameter
Frequency
Target / Action
Arterial line BP
Continuous (art line mandatory in ICU)
Reduce MAP no more than 25% in the first hour. Cuff pressures are insufficient for IV drip titration -art line is standard of care.
MAP during titration
q5–15 min while adjusting IV drip
First hour: ≤ 25% MAP reduction. Next 2–6h: target ~160/100. Next 24–48h: gradual normalization. Too fast → watershed stroke.
Neuro checks
q1–2h during active titration
GCS, pupil reactivity, focal deficits, level of consciousness. New deficit during BP lowering → stop titration, allow BP to rise, urgent imaging (stroke?).
Urine output
q1h (Foley)
UOP ≥ 0.5 mL/kg/hr. Declining UOP during BP reduction = renal hypoperfusion -may need to allow higher BP target.
Creatinine
q12–24h
Trend from baseline. Rising Cr suggests renal end-organ injury or overly aggressive BP lowering. Adjust target accordingly.
Troponin
On admission, repeat at 6h if elevated or ongoing chest pain
Hypertensive emergency can cause demand ischemia (type 2 MI). Elevated troponin changes management -cardiology consult.
Fundoscopic exam
On admission, repeat if worsening
Papilledema, flame hemorrhages, cotton-wool spots, AV nicking. Presence confirms end-organ damage and classifies as true emergency vs urgency.
Transition to oral agents
After 12–24h stable on IV drip
Start long-acting oral antihypertensives (amlodipine, lisinopril, etc.) with IV drip overlap. Wean drip gradually as oral agents take effect (24–48h). Do not abruptly stop IV.
BP reduction timeline: 25% MAP reduction in first hour → 160/100 over next 2–6h → gradual normalization over 24–48h. Exception: aortic dissection -target SBP < 120 + HR < 60 within minutes (esmolol + nicardipine). Exception: ischemic stroke -do NOT lower BP unless > 220/120 (or > 185/110 if tPA candidate).
⚡ Summary
Summary
The Number Does Not Define It
Hypertensive emergency is severe hypertension with acute end-organ damage; urgency is the same number without it.The workup answers one question: is there end-organ damage? Yes means IV therapy and monitored care; no means oral therapy and outpatient follow-up. Treating a high number in an asymptomatic patient causes harm.
Look for the Damage Systematically
Brain: encephalopathy, stroke, PRES.Heart: ACS, acute pulmonary edema, aortic dissection.Kidney: acute kidney injury, hematuria and proteinuria.Eye: retinal hemorrhages, exudates, papilledema.Blood: microangiopathic hemolysis.Fundoscopy is quick, free and frequently omitted.
Lower It Slowly, With Two Exceptions
Reduce the mean arterial pressure by no more than 25% in the first hour, then toward 160/100 over the next 2 to 6 h.Cerebral autoregulation is shifted rightward in chronic hypertension, so a rapid drop causes watershed infarction, blindness and renal failure.Aortic dissection is the aggressive exception; ischemic stroke is the conservative one.
Exclude Dissection Before Choosing a Drug
Severe hypertension with chest or back pain means CT angiography of the chest, abdomen and pelvis immediately.Target a systolic of 100 to 120 and a heart rate below 60 within 20 minutes, using a beta blocker FIRST (esmolol or labetalol), then a vasodilator. Do not give nitroprusside or any vasodilator before rate control: reflex tachycardia increases aortic wall shear stress and extends the dissection.
Match the Drug to the Organ
Nicardipine or clevidipine for most emergencies, including neurologic ones, because they are titratable and do not raise intracranial pressure. Labetalol for stroke and dissection. Nitroglycerin for pulmonary edema and ACS. Hydralazine or labetalol for preeclampsia. Phentolamine for pheochromocytoma and cocaine.
Never Beta-Block Alone in Catecholamine Excess
In pheochromocytoma, beta blockade without prior alpha blockade leaves unopposed alpha stimulation and precipitates a paradoxical hypertensive crisis.The same principle applies in cocaine and amphetamine toxicity, where benzodiazepines, nitrates and phentolamine are the appropriate agents.
Use an Arterial Line and an Infusion, Not Boluses
Titratable infusions with continuous monitoring, because intermittent boluses produce the overshoot that causes the ischemic complications. Avoid sublingual nifedipine entirely: it drops the pressure precipitously and unpredictably and has caused strokes and infarcts.
Find the Reason It Got This High
Non-adherence and abrupt withdrawal of clonidine or a beta blocker are the commonest causes, and clonidine withdrawal produces a rebound crisis that needs the drug restarted rather than a new one added. Also screen for renal artery stenosis, primary aldosteronism, pheochromocytoma, thyroid disease, sleep apnea, cocaine and sympathomimetics, and NSAIDs. Discharge with a regimen the patient can actually afford and take, plus follow-up within days.
RoundsRx Infographic Series · #43 · Cardiovascular · PDF 155 KB
Text version
ICU · One Pager
Hypertensive Emergency
End-organ damage defines the emergency. The organ being damaged determines the drug and the target. Never drop BP > 25% in first hour.
🚨 Exclude First -Aortic Dissection
Chest/back pain + very high BP → CTA chest/abdomen NOW
Target SBP < 120, HR < 60 ASAP
Esmolol + nicardipine or nitroprusside
Never nitrates alone (reflex tachycardia)
📐 BP Reduction Rule
Reduce MAP ≤ 25% in first hour
Then to 160/100 over 2–6h
Exception: Dissection (aggressive) and ischemic stroke (conservative)
Ischemic stroke: only treat if BP > 220/120
💊 Drug by Syndrome
Most emergenciesNicardipine 5–15 mg/hr IV
Aortic dissectionEsmolol + nicardipine
ACS / pulmonary edemaNitroglycerin IV + labetalol
Stroke (hemorrhagic)Nicardipine → SBP < 140
EclampsiaLabetalol IV + MgSO₄
PheochromocytomaPhentolamine (α first!) then β-blocker
⚠️ Pheo Rule
α-block FIRST with phentolamine
THEN add beta-blocker
Beta-block first → unopposed α → crisis
🧠 Why Not Too Fast?
Chronic HT shifts autoregulation rightward
Rapid drop → cerebral ischemia
Watershed infarcts, blindness, renal infarction
CardiologyChronicCommon
Hypertension - Outpatient Management
~50% of US adults have HTN, and it's the #1 modifiable cardiovascular risk factor. Diagnosis, workup, drug selection by compelling indication, resistant-HTN evaluation, and SPRINT-era BP targets. For acute hypertensive emergency, see HTN Emergency.
🔍 Overview
Staging (ACC/AHA 2017)
Category
SBP (mmHg)
DBP (mmHg)
Action
Normal
< 120
< 80
Reassess in 1 year. No drugs.
Elevated
120-129
< 80
Lifestyle only. Reassess in 3-6 months. No drugs.
Stage 1
130-139
OR 80-89
Lifestyle. Single-drug monotherapy if ASCVD risk ≥ 10%, established CV disease, DM, or CKD.
Stage 2
≥ 140
OR ≥ 90
Lifestyle plus pharmacotherapy. Two-drug combination upfront if SBP ≥ 20 or DBP ≥ 10 above target (most stage 2 patients). Single-pill combinations preferred for adherence.
Resistant HTN
BP above goal at any threshold
BP above target despite 3 drugs of different classes (one a diuretic) at maximally tolerated doses, OR controlled BP requiring 4+ drugs. Rule out pseudoresistance first; then secondary causes; then add spironolactone as the 4th agent (PATHWAY-2). See Resistant HTN tab.
Hypertensive urgency
> 180
OR > 120
NO end-organ damage. Asymptomatic or mild headache only. Outpatient management: restart or up-titrate home oral meds, lower BP gradually over 24-72 hours. NO IV agents; no ICU. Rapid lowering causes watershed strokes.
Hypertensive emergency
> 180
OR > 120
WITH end-organ damage (CNS, cardiac, renal, retinal). ICU. IV nicardipine or labetalol. Lower MAP by ≤ 25% in the first hour. See HTN Emergency.
Diagnosis requires confirmation. Two or more elevated readings on separate occasions, or home/ambulatory monitoring confirming the office reading. Single-visit diagnosis misses white-coat HTN (over-treats) and masked HTN (under-treats).
Why It Matters
Most common modifiable CV risk factor. Affects ~50% of US adults, and a higher fraction of older adults.
Risk doubles for every 20/10 mmHg above 115/75. Linear, log-linear relationship with stroke, MI, HF, CKD, dementia.
Asymptomatic until end-organ damage occurs. Patients don't feel HTN. Adherence is the central battle.
Black patients develop HTN earlier, with more severe target-organ damage and lower response to ACEi/ARB monotherapy. Thiazide or CCB first-line.
Secondary HTN -~5-10%. Identifiable cause. Higher prevalence in atypical presentations: onset < 30 or sudden onset > 65, severe or resistant HTN, abrupt change in stable HTN, target-organ damage out of proportion.
Top secondary causes to think about: primary aldosteronism (most common, ~5-13% of HTN, often normokalemic), obstructive sleep apnea, renovascular disease, CKD, pheochromocytoma, Cushing's syndrome, thyroid disease, oral contraceptives / NSAIDs / decongestants. See the Resistant HTN tab for the workup algorithm.
🧪 Workup
Confirming the Diagnosis
Office BP technique matters. Patient seated quietly 5 minutes, feet on floor, arm at heart level, no caffeine/exercise/smoking 30 min prior, appropriate cuff size (cuff too small = falsely high). Two readings, 1-2 minutes apart, average them.
Confirm with out-of-office monitoring when possible. Home BP monitoring (HBPM) is most practical; 24-hour ambulatory BP monitoring (ABPM) is the gold standard.
White-coat HTN -elevated office, normal home/ABPM. Don't treat with drugs; monitor.
Baseline kidney function + drug-safety screen + flag for secondary HTN
eGFR < 60 = stage 3 CKD: tightens BP target to < 130/80, makes ACEi/ARB a compelling (renal-protective) indication, and triggers dose-adjustment for renally cleared drugs (atenolol, nadolol, lisinopril). eGFR < 30: HCTZ/chlorthalidone become ineffective (switch to loop or metolazone) and MRAs become dangerous (hyperK risk). K⁺ < 3.5 unprovoked → primary aldosteronism until proven otherwise (workup with morning aldosterone-renin ratio). K⁺ > 5.0: hold MRA, reduce or hold ACEi/ARB. Bicarb low + K⁺ high in a diabetic with CKD: think Type 4 RTA. Always check K⁺ before starting any RAAS blocker or thiazide.
Fasting lipids
Required input for the ASCVD calculator + screen for statin indication + flag metabolic syndrome
The ASCVD 10-year risk score literally needs lipid values to compute -the Pooled Cohort Equation requires total cholesterol and HDL. Without them you can't risk-stratify. The score then determines stage 1 HTN management: treat with drugs if ASCVD ≥ 10%, lifestyle alone if < 10%. Lipids also independently identify statin indications: LDL ≥ 190 (high-intensity statin), DM age 40-75 (moderate-to-high), ASCVD ≥ 7.5% (moderate-to-high). Many HTN patients qualify for a statin separately, and the lipid panel is the only way to find out. Reveals metabolic syndrome (HTN + low HDL + high TG + central obesity + glucose intolerance), which warrants aggressive lifestyle and comorbidity treatment beyond just BP control.
HbA1c or fasting glucose
Screen for diabetes (compelling indication) + flag prediabetes / metabolic syndrome
A1c ≥ 6.5% = diabetes: tightens BP target to < 130/80 (ADA 2024), makes ACEi/ARB the preferred class if any albuminuria (UACR ≥ 30), and adds SGLT2i as a compelling indication for cardio-renal protection regardless of A1c. DM + albuminuric CKD: stack ACEi/ARB + SGLT2i + finerenone (FIDELIO-DKD / FIGARO-DKD). A1c 5.7-6.4% = prediabetes: nearly doubles 10-year ASCVD risk; aggressive lifestyle intervention with weight loss, DASH, exercise. Fasting glucose > 250 in an undiagnosed patient: assume long-standing DM with possible silent microvascular damage; lower threshold for ACEi/ARB and screen for retinopathy/nephropathy. Watch for hypoglycemia masking on BBs, especially atenolol, in insulin-treated diabetics.
TSH
Screen for a reversible secondary HTN cause
Hyperthyroidism (TSH < 0.1): causes systolic HTN with wide pulse pressure from increased CO. ~10-15% develop AFib. Often presents with palpitations, weight loss, tremor. Treat the thyroid first with methimazole (PTU in first trimester or thyroid storm) plus a BB (propranolol blocks T4→T3 conversion at high doses) for adrenergic symptoms. BP usually normalizes. Hypothyroidism (TSH > 10): causes diastolic HTN from peripheral vasoconstriction and reduced CO. Levothyroxine replacement normalizes BP within 6-8 weeks; recheck BP before adding antihypertensives. Subclinical hypothyroidism (TSH 4.5-10): contribution to HTN is debated; treatment for HTN benefit alone is unproven, but treat if TSH > 10, pregnancy, or symptoms.
Urine albumin/creatinine ratio (UACR)
Detect end-organ damage + identify compelling indication for ACEi/ARB
UACR < 30 mg/g: normal. No specific drug-class shift from this lab alone. UACR 30-300 (microalbuminuria): early hypertensive or diabetic nephropathy. Strong indication for ACEi or ARB even in stage 1 HTN (renal-protective per AASK 2002). Tightens BP target to < 130/80. UACR > 300 (macroalbuminuria): overt nephropathy. Add SGLT2i (DAPA-CKD 2020), goal BP < 130/80, possibly < 120/80 if tolerated. UACR > 3000 (nephrotic-range): workup for primary glomerular disease (FSGS, membranous, MPGN), consider renal biopsy. New UACR > 30 in an older patient without DM: think early hypertensive nephropathy and tighten BP target before drugs would otherwise be indicated.
ECG
Detect cardiac end-organ damage + screen for silent MI / arrhythmia
LVH (Sokolow-Lyon: S in V1 + R in V5 or V6 ≥ 35 mm; Cornell: S in V3 + R in aVL > 28 mm men / 20 mm women) = target-organ damage. Tightens BP target and shifts drug choice away from BBs toward ARB or ACEi per LIFE, 2002. Q waves or R-wave loss: prior silent MI = compelling indication for BB + ACEi. LBBB: think underlying cardiomyopathy → get an echo; if EF ≤ 35% with QRS ≥ 150, CRT candidate. Left atrial enlargement (P-wave > 120 ms or biphasic in V1): correlates with diastolic dysfunction and predicts AFib. New AFib on screening ECG changes management dramatically -anticoagulation if CHA₂DS₂-VASc ≥ 2, plus rate control. ST/T-wave changes: ischemia workup before tightening BP target (could be active angina).
Not routine for every HTN patient. Order when: ECG suggests LVH, exertional dyspnea or HFpEF symptoms, atypical features, severe HTN in a young patient, or murmur on exam. Echo-confirmed LVH (LV mass index > 115 g/m² men / > 95 g/m² women): confirms target-organ damage even when ECG is equivocal -tightens BP target and prefers ARB/ACEi over BB. Diastolic dysfunction (E/e′ > 14, LA volume index > 34 mL/m²): HFpEF is evolving -intensify BP control and add SGLT2i (EMPEROR-Preserved, DELIVER). Reduced EF < 50%: de novo HFrEF discovered -pivots management to the four GDMT pillars. Aortic root dilation in a tall, thin young patient: think Marfan; refer for genetic counseling and BB to reduce dP/dt. Aortic coarctation may explain unexpected HTN with arm-leg BP differential.
Pattern: every initial lab answers one of four questions. (1) End-organ damage already present? (UACR, ECG, echo). (2) Reversible secondary cause? (BMP K⁺, TSH). (3) Compelling indication that drives drug choice? (A1c, UACR, BMP). (4) Drug-safety baseline? (BMP for Cr / K⁺ before RAAS or thiazide). One lab can answer multiple.
When to Screen for Secondary Causes
Resistant HTN (uncontrolled on 3 drugs including a diuretic at maximally tolerated doses)
Onset before age 30 or sudden new HTN after 65
Severe HTN at presentation (≥ 180/120) without prior diagnosis
Abrupt loss of control in previously stable HTN
Hypokalemia (especially unprovoked) or hypertensive end-organ damage out of proportion to severity
Episodic HTN with palpitations, headache, sweating (think pheochromocytoma)
Abdominal bruit, flash pulmonary edema, AKI on ACEi/ARB (think renovascular disease)
🚨 Management
▶ How to Escalate HTN Therapy, Step by Step (tap to expand)
Scope: uncomplicated essential HTN in adults. If a compelling indication is present (HFrEF, CKD with albuminuria, post-MI, DM, AF, pregnancy), drug choice is driven by the comorbidity (see Compelling Indications table). At every step, reinforce lifestyle (DASH + sodium < 1.5-2 g/day + weight loss + exercise stacks to a 20+ mmHg SBP drop, comparable to two-drug therapy).
Step 1: Confirm diagnosis before any drug
Check
What
Why
Out-of-office BP
Home BP monitoring (HBPM) for 7 days, or 24-hour ambulatory BP (ABPM)
~20% of "stage 1" office HTN is white-coat (normal home/ABPM, no drug needed) and ~10-15% of "normal" office BP is masked HTN (high home/ABPM, treat aggressively). Treating a number rather than a phenotype leads to hypotension, falls, and missed disease.
Correct technique
Seated 5 min, no caffeine/exercise 30 min prior, arm at heart level, appropriate cuff size, 2 readings averaged
Cuff too small adds ~10 mmHg; arm below heart adds ~5 mmHg. Bad technique fakes resistant HTN.
Identifies end-organ damage (LVH, CKD, albuminuria) and secondary-HTN clues. ASCVD risk drives the Stage 1 decision (treat at lower threshold if risk ≥ 10%).
Step 2: Initiate based on stage and risk
BP Stage
What to Do
Why
Normal/Elevated (< 130/80, or 120-129/< 80)
Lifestyle only. Reassess in 3-6 months.
No mortality benefit from drugs in this range. Capture early via lifestyle.
Stage 1 (130-139/80-89)
Lifestyle for 3-6 months; add monotherapy if 10-yr ASCVD risk ≥ 10%, established ASCVD, DM, CKD, or HF
SPRINT showed CV benefit of intensive control in high-risk patients. In low-risk Stage 1, lifestyle alone is enough.
Stage 2 (≥ 140/90, or > 20/10 above target)
Start dual therapy upfront, ideally as a single-pill combination
Monotherapy rarely closes a > 20/10 gap; needing 2-3 visits to get there wastes time and erodes adherence. ACCOMPLISH (2008): ACEi + amlodipine beat ACEi + HCTZ by 20% on MACE in high-risk patients. Single-pill combos improve adherence ~30%.
First-line drug picks (no compelling indication):
Non-Black: any of thiazide (chlorthalidone preferred), ACEi/ARB, or dihydropyridine CCB (amlodipine). ALLHAT showed all three are equivalent at population level.
Black patient: thiazide or CCB first (ALLHAT: ACEi monotherapy is less effective at lowering BP and reduces stroke less). Add ACEi/ARB if CKD with albuminuria, DM, or HFrEF.
Recheck BP and BMP at 2-4 weeks after starting or uptitrating. Catches thiazide-induced hypokalemia/hyponatremia/hyperuricemia and RAAS-induced hyperkalemia/Cr bump while they're still reversible. A Cr rise ≤ 30% on ACEi/ARB is expected and acceptable; only stop if rise > 30% or K+ > 5.5. Then titrate each agent to max tolerated before adding the next.
Step 4: Add the third agent
The classic 3-drug combo is ACEi/ARB + CCB + thiazide ("A + C + D"). Whichever class you didn't use in steps 2-3 is the third. If already on ACEi + CCB, add chlorthalidone. If on ACEi + thiazide, add amlodipine. This combination handles ~85-90% of HTN. Re-confirm out-of-office BP at this point, white-coat unmasking is common as the office number drops.
Step 5: If still uncontrolled on 3 drugs → resistant HTN workup
Step
What
Why
Confirm true resistance
3 agents at max-tolerated doses, one being a diuretic, ABPM or HBPM confirms elevated
~30-50% of "resistant" cases are pseudo-resistance: non-adherence (most common, check pill counts and refill data), white-coat effect, bad measurement technique, or undertreated dose. Get this right before secondary workup.
Switch HCTZ → chlorthalidone if not already
Chlorthalidone 12.5-25 mg daily
Longer half-life (40-60h vs 6-15h) and better 24h BP control; many patients labeled "resistant" on HCTZ become controlled on equipotent chlorthalidone.
Add 4th agent: spironolactone
12.5-25 mg daily (watch K+)
PATHWAY-2 (2015) showed spironolactone reduced home SBP an additional 8-10 mmHg, beating bisoprolol or doxazosin. First-line 4th agent per 2017 ACC/AHA.
Try patiromer or sodium zirconium cyclosilicate (SZC) before stopping RAAS or MRA
Mortality benefit of RAAS-blockade and MRA is lost on discontinuation. K+ binders preserve the regimen (DIAMOND, 2022).
AKI with Cr rise > 30% after ACEi/ARB start
Hold RAAS-blockade and screen for bilateral renal artery stenosis (renal duplex, MRA)
RAS unmasks itself when ACEi/ARB drops perfusion pressure to the post-stenotic kidney. Don't just reflexively stop and move on.
Gout / hyperuricemia
Prefer losartan (mildly uricosuric) or CCB; avoid thiazide if possible
Thiazides raise uric acid and trigger flares. If a thiazide is needed for BP, prophylax with allopurinol.
Hypertensive urgency (BP > 180/120, asymptomatic)
Restart held home meds, oral agent (clonidine, captopril, labetalol). Outpatient follow-up < 1 week. Do NOT lower > 25% in 24 hours.
Rapid lowering risks watershed stroke and MI. Numbers without end-organ damage are urgency, not emergency.
Hypertensive emergency (end-organ damage)
IV nicardipine, labetalol, clevidipine; lower MAP 25% in first hour, then to 160/100 over 2-6 hours. See HTN Emergency
End-organ damage (encephalopathy, MI, dissection, AKI, pulmonary edema) requires controlled IV lowering on telemetry.
▶ BP Targets by Population (tap to expand)
Population
Target
Evidence
General adult, high CV risk
< 130/80
SPRINT, 2015 (intensive < 120 SBP reduced MACE 25%, mortality 27%; ACC/AHA adopted < 130/80 as practical target). Earlier, HOT, 1998 established DBP < 90 as the baseline target and < 80 in DM.
Diabetes
< 130/80
ADA 2024, ACC/AHA 2017. ACCORD-BP, 2010: intensive < 120 SBP did NOT beat < 140 for the primary CV composite in DM and caused more AEs, driving the compromise to < 130/80.
CKD (any stage)
< 130/80
KDIGO 2024. Even tighter (< 120/80) if proteinuric.
HYVET, 2008 showed treatment benefit even in patients ≥ 80. SPRINT included older adults with benefit. STEP, 2021 reproduced SPRINT-like benefit in elderly.
Older adult, frail / multiple comorbidities
< 140/90 reasonable
Avoid orthostatic falls. Target individualized.
Pregnancy
< 140/90 (treat at ≥ 140/90)
CHAP, 2022. Labetalol, nifedipine, methyldopa are first-line. Avoid ACEi/ARB (teratogenic, especially 2nd-3rd trimester).
SPRINT vs ACCORD-BP: why the intensive target splits on diabetes
Same intensive target (SBP < 120), opposite results, divided by diabetes status. This trial pair is the reason the guideline target settled at < 130/80 rather than < 120.
SPRINT, 2015 (nondiabetic, N = 9,361): intensive SBP < 120 vs < 140 reduced the primary CV composite 25% and all-cause mortality 27%. Stopped early for benefit. (Excluded diabetes and prior stroke.)
ACCORD-BP, 2010 (type 2 diabetes, N = 4,733): intensive SBP < 120 did NOT reduce the primary CV composite or mortality. Only stroke fell (~41%), while serious treatment-related adverse events rose (hypotension, syncope, hyperkalemia, renal effects).
Bedside takeaway: push toward SBP < 120 only in high-risk nondiabetic patients who tolerate it. In diabetes, settle at < 130/80, because the extra push to < 120 buys some stroke reduction at the cost of more harm and no mortality or composite benefit.
Lifestyle Interventions (always first or concurrent)
Intervention
Approximate SBP / DBP Effect
Note
DASH diet
↓ 11 / 3 mmHg
DASH, 1997: high in fruits, vegetables, low-fat dairy; reduced saturated fat. DASH-Sodium, 2001 showed sodium restriction is additive.
Sodium restriction (< 1.5-2 g/day)
↓ 5 / 3 mmHg
Greater effect in Black patients, older adults, salt-sensitive HTN.
Weight loss
↓ ~1 / 1 mmHg per kg
Sustained effect. Most impactful in obese patients.
Aerobic exercise
↓ 4 / 3 mmHg
≥ 90-150 min/week moderate intensity.
Alcohol reduction
↓ 4 / 3 mmHg
Limit to ≤ 2 drinks/day men, ≤ 1 drink/day women.
Smoking cessation
Variable acute, large CV mortality benefit
Doesn't lower chronic BP much, but huge CV impact.
Stacking lifestyle changes is additive. A patient who adopts DASH plus sodium restriction plus weight loss plus exercise can achieve a 20+ mmHg SBP drop, comparable to two-drug therapy.
First-line Drug Selection
Initiate two-drug combination therapy if BP is > 20/10 above target. Monotherapy is rarely adequate at stage 2. Single-pill combinations improve adherence dramatically. When choosing a combination, ACCOMPLISH, 2008 showed ACEi + amlodipine outperformed ACEi + HCTZ for CV outcomes (20% relative risk reduction in MACE) in high-risk patients.
Patient
First-line Choice
Why
General non-Black, no compelling indication
Thiazide (chlorthalidone preferred) OR ACEi/ARB OR dihydropyridine CCB (amlodipine)
All three classes have similar BP-lowering and CV outcome benefit at population level.
Black patient (no compelling indication)
Thiazide OR CCB (not ACEi/ARB monotherapy)
ALLHAT, 2002: ACEi monotherapy is less effective at lowering BP in Black patients. Add an ACEi/ARB if concomitant CKD, DM with albuminuria, or HFrEF.
Compelling indication present
See compelling indications table below
Drug selection driven by comorbidity, not just BP.
Compelling Indications (let comorbidity drive drug choice)
ACEi, ARB, ARNI, MRA, direct renin inhibitors (teratogenic).
Follow-up Cadence
After starting or changing therapy: recheck BP and BMP in 2-4 weeks.
Stable on regimen: visit q3-6 months; BMP q6-12 months -monitor for thiazide effects (hypokalemia, hyponatremia, hyperuricemia, mild glucose intolerance) and RAAS-inhibitor effects (hyperkalemia, Cr bump). Recheck BMP within 1-2 weeks any time you start or uptitrate a thiazide, ACEi/ARB, ARNI, or MRA -that's the highest-yield window for catching these.
Home BP monitoring at every visit. Target: home average matches office target. If home is consistently lower than office → suspect white-coat effect.
Non-adherence is the most common reason for "resistance." Always check pill counts, refill data, and consider direct-observed dosing or single-pill combinations before escalating.
Time-of-day dosing doesn't matter.TIME, 2022 showed evening dosing does NOT reduce CV events vs morning. Pick the time the patient is most likely to remember.
💊 Medications
First-line Classes
Drug
Starting → Target Dose
Key Notes
Chlorthalidone PREFERRED THIAZIDE
12.5-25 mg PO daily (max 25-50)
Preferred over HCTZ -longer half-life (40-60h vs 6-15h), better 24h BP control, may reduce CV events more. Watch hypokalemia, hyperuricemia, hyponatremia. Outcome data: ALLHAT, 2002 (chlorthalidone matched amlodipine/lisinopril for CHD and was superior for preventing heart failure; established thiazide as first-line); SHEP, 1991 (cut stroke 36% in elderly isolated systolic HTN).
Hydrochlorothiazide (HCTZ) ALTERNATIVE
25-50 mg PO daily
Cheaper, more familiar, but weaker 24h coverage. Use chlorthalidone if available. Note: the landmark outcome trials (ALLHAT, 2002, SHEP, 1991) used chlorthalidone, not HCTZ -HCTZ's CV-outcome evidence is weaker.
Amlodipine (Norvasc) DHP CCB
2.5-5 → 10 mg PO daily
Excellent for systolic HTN in elderly. Pedal edema common (dose-dependent, not from fluid retention). Safe in HFrEF. ALLHAT, 2002 (CV-equivalent to thiazide); ACCOMPLISH, 2008 (ACEi + amlodipine beat ACEi + HCTZ by 20% on MACE; the preferred dual combo).
Lisinopril (Zestril) ACEi
10 → 40 mg PO daily
Cough (~10%, persistent) and angioedema (rare but serious). Hyperkalemia. Avoid in pregnancy.ALLHAT, 2002 (equivalent overall, but weaker BP-lowering and stroke protection as monotherapy in Black patients).
Losartan (Cozaar) ARB
50 → 100 mg PO daily
No cough. Uricosuric -preferred ARB in HTN with gout/hyperuricemia. Hyperkalemia. Avoid in pregnancy.LIFE, 2002 (beat atenolol on stroke in LVH despite similar BP).
Metoprolol succinate (Toprol-XL) BB - COMPELLING ONLY
25 → 200 mg PO daily
Not first-line for uncomplicated HTN (less stroke reduction than thiazide/CCB/ACEi). Use for HFrEF, post-MI, AFib rate control. MERIT-HF, 1999 (HFrEF mortality benefit).
Carvedilol (Coreg) BB - HFrEF
3.125 BID → 25 BID
Alpha + beta blockade. HFrEF preferred BB. COPERNICUS, 2001 (mortality ↓35% in severe HFrEF); COMET, 2003 (beat metoprolol tartrate on mortality).
Olmesartan pearl, sprue-like enteropathy. Olmesartan (Benicar; also in Azor, Benicar HCT, Tribenzor) can cause a distinctive sprue-like enteropathy: severe chronic diarrhea, weight loss, and small-bowel villous atrophy that mimics celiac disease. The catch: celiac serologies are negative and it does NOT respond to a gluten-free diet, and onset can be months to years after starting. It resolves on stopping the drug (and recurs on rechallenge). FDA warning 2013 (Mayo Clinic case series). Why it matters: in any patient on olmesartan with unexplained chronic diarrhea and seronegative villous atrophy, stop the drug before labeling it refractory celiac, that single step is often curative.
Add-on / Combination Agents
Drug
Dose
Role
Spironolactone (Aldactone)
12.5-50 mg daily
Fourth-line for resistant HTN (PATHWAY-2, 2015). Also for primary aldosteronism. Watch hyperkalemia, gynecomastia (~10%, switch to eplerenone if bothersome).
Hydralazine (Apresoline)
10-50 mg PO TID-QID (start 10 mg QID)
Direct arteriolar vasodilator. Useful in pregnancy and as add-on. Reflex tachycardia (pair with BB), drug-induced lupus at > 200 mg/day or in slow acetylators.
Clonidine (Catapres)
PO: 0.1 mg BID, titrate to max 0.6 mg/day. Patch: 0.1-0.3 mg/24h, change weekly.
Central alpha-2 agonist. Avoid as monotherapy -severe rebound HTN if missed doses. Patch helpful for adherence-limited resistant HTN.
Doxazosin (Cardura)
1 → 16 mg daily (start 1 mg qhs)
Alpha-blocker. Add-on for resistant HTN, especially with BPH. Monotherapy inferior (ALLHAT, 2002). Watch first-dose orthostatic syncope -dose at bedtime.
Diltiazem ER (Cardizem CD, Tiazac)
180-360 mg PO daily
Non-DHP CCB. Useful for HTN + AFib needing rate control. Avoid in HFrEF (negative inotropy).
Verapamil ER (Calan SR, Verelan)
180-480 mg PO daily
Non-DHP CCB. Same role as diltiazem; more constipation. Avoid in HFrEF.
Single-pill combinations cut pill burden and dramatically improve adherence. Most guidelines now recommend starting Stage 2 HTN with a single-pill dual combination rather than two separate pills.
Combination
Brand Name
Available Strengths (mg)
ACEi/ARB + Amlodipine (preferred combo per ACCOMPLISH)
ARB + Neprilysin Inhibitor (HFrEF, not first-line HTN)
Sacubitril + valsartan
Entresto
24/26, 49/51, 97/103 BID
Don't combine ACEi + ARB. No CV benefit but significantly more hyperkalemia, AKI, and hypotension (ONTARGET, 2008). Same applies to ACEi/ARB + direct renin inhibitor (aliskiren).
▶ Why Beta-Blockers Aren't First-Line for Uncomplicated HTN (tap to expand)
BBs lower brachial cuff BP just as well as thiazides, CCBs, and ACEi/ARB at equivalent doses, but they consistently underperform for stroke and CV outcomes. Two converging mechanisms explain this gap.
Mechanism 1: BBs don't lower CENTRAL aortic pressure as well as they lower brachial pressure
The pressure your heart, brain, and kidneys actually see is the aortic root pressure, not the brachial cuff pressure. The two are usually close, but not always:
The arterial pulse generates a forward wave that travels distally and a reflected wave that bounces back from peripheral arteries.
In young, compliant arteries, the reflected wave returns in diastole -augmenting coronary perfusion (good).
In stiff aging arteries, pulse wave velocity is faster and the reflected wave returns earlier, in late systole -augmenting central aortic systolic pressure (bad).
BBs slow heart rate → longer ejection time → reflected wave returns even earlier in systole → more central pressure augmentation. The brachial cuff misses this because the reflection adds less to peripheral readings.
CCBs and ACEi/ARB vasodilate peripheral arteries → reduce wave reflection → drop central pressure more than BBs do at the same brachial reading.
CAFE substudy of ASCOT, 2006: amlodipine ± perindopril vs atenolol ± thiazide produced near-identical brachial BP, but central aortic pressure was 4-5 mmHg lower on the CCB/ACEi arm. This central pressure gap explained the CV outcome benefit seen in the parent ASCOT-BPLA, 2005 trial.
Mechanism 2: Other BB disadvantages in uncomplicated HTN
Worse stroke prevention at equipotent BP (LIFE 2002, MRC 1992, ASCOT 2005 all consistent).
Adverse metabolic profile -atenolol increases new-onset diabetes (especially when combined with thiazide), promotes weight gain, worsens lipid profile.
Bradycardia and fatigue reduce adherence in working-age patients.
Withdrawal rebound HTN if doses missed; abrupt discontinuation is dangerous.
Atenolol is the worst offender -most of the negative trials used atenolol. Vasodilating BBs (carvedilol, nebivolol, labetalol) have a more favorable hemodynamic profile because they reduce peripheral vascular resistance and may not worsen central pressure as much.
When BBs ARE Indicated (compelling indications)
Indication
Preferred BB(s)
Why
HFrEF
Carvedilol, metoprolol succinate, bisoprolol
Mortality benefit, one of the four GDMT pillars. Only these three have HFrEF trial evidence.
Post-MI (first 1-3 years)
Metoprolol succinate, carvedilol, bisoprolol
Mortality reduction in the early post-MI window. Continue at least 1 year, often longer with reduced EF.
Atrial fibrillation needing rate control
Metoprolol, atenolol, bisoprolol, carvedilol
Slows AV nodal conduction. Drug selection by HF status. Diltiazem/verapamil are alternatives if no HFrEF.
Lower HR BEFORE BP -reducing dP/dt minimizes wall shear stress propagating the dissection.
Thyrotoxicosis / thyroid storm
Propranolol
Blocks adrenergic excess; propranolol also blocks T4→T3 conversion at high doses.
Hypertension in pregnancy
Labetalol
First-line in pregnancy (alpha + beta blockade). Methyldopa and nifedipine are alternatives.
Migraine prophylaxis with comorbid HTN
Propranolol, metoprolol
Well-validated for migraine prevention; treats both conditions.
Essential tremor with HTN
Propranolol
First-line for tremor. Dual indication.
Pheochromocytoma (after alpha block)
Any BB, after phenoxybenzamine
Never start BB before alpha block -unopposed alpha stimulation → hypertensive crisis.
Resistant HTN (4th/5th line)
Bisoprolol
PATHWAY-2 2015 showed spironolactone is preferred 4th drug, but bisoprolol is reasonable 5th if HR > 70 or as alternative when MRA is contraindicated.
One-line takeaway: if your HTN patient has no compelling indication, a thiazide, CCB, or ACEi/ARB will protect them better than a beta-blocker -even though the cuff numbers look the same. The cuff lies; central aortic pressure tells the truth.
▶ Antihypertensives in CKD & AKI - What to Avoid & What to Use (tap to expand)
CKD changes the pharmacology of every antihypertensive class. Some accumulate (toxicity), some lose efficacy, some cause hyperkalemia, and some are actively renal-protective. Pick agents based on eGFR and compelling indications.
Atenolol is the classic CKD trap. ~50% renally excreted unchanged. Half-life extends from 6-9h (normal kidneys) to 16-30+ hours in advanced CKD. Accumulation causes symptomatic bradycardia, hypotension, fatigue, AV block, and hypoglycemia unawareness in diabetics. Dialyzable, so HD patients must be dosed post-dialysis. Switch to a hepatically cleared BB (metoprolol, carvedilol, labetalol) whenever possible.
Beta-blockers in CKD
Drug
Clearance
CKD Action
Atenolol AVOID
~50% renal
Avoid if possible. If needed: max 50 mg/day at eGFR 15-35, max 25 mg/day or QOD at eGFR < 15. Dose post-HD (dialyzable).
Nadolol AVOID
Renal
Very long half-life that extends further in CKD. Switch to a hepatic BB.
Sotalol AVOID
Renal
Renally cleared and QT-prolonging. Dangerous combination in CKD. If used for rhythm control, dose-adjust by CrCl with frequent QTc monitoring.
Bisoprolol ADJUST
~50% renal / 50% hepatic
Mild adjustment. Start 2.5 mg at eGFR < 40. Still acceptable as an HFrEF GDMT pillar in CKD.
Metoprolol succinate / tartrate PREFERRED
Hepatic
No renal dose adjustment. Preferred BB in CKD when there's a compelling indication.
Carvedilol PREFERRED
Hepatic
No renal dose adjustment. HFrEF first-line, also useful for CKD with HF overlap.
Labetalol, propranolol, nebivolol PREFERRED
Hepatic
No renal adjustment. Labetalol is preferred in pregnancy with CKD.
Renally cleared. Renal-protective in proteinuric CKD (AASK, 2002). Hyperkalemia and 10-30% Cr rise on initiation.
Preferred in CKD with albuminuria (UACR > 30). Mild dose adjustment for severe CKD. Hold if Cr rises > 30% from baseline or K⁺ > 5.5. The expected hemodynamic Cr bump (≤ 30%) is OK and reverses on stopping.
Fosinopril UNIQUE
The only ACEi cleared hepatically (the rest are renal).
No renal dose adjustment. Useful when other ACEi accumulate or patient is on multiple renally cleared drugs.
Same renal-protective and hyperK profile as ACEi. Most don't need major dose adjustment.
Same role as ACEi in CKD. Switch from ACEi if cough or angioedema. Don't combine with ACEi (ONTARGET, 2008: more AKI, hyperK, hypotension, no benefit).
Sacubitril/valsartan (Entresto, ARNI) CAUTION
Limited data at eGFR < 30. Same hyperK and hypotension concerns as ACEi/ARB.
Avoid initiation at eGFR < 30. If eGFR drops below 30 on therapy, individualize.
Aliskiren (direct renin inhibitor) AVOID
High AKI and hyperkalemia risk, especially when combined with ACEi or ARB.
Avoid in CKD. Never combine with ACEi/ARB.
Diuretics in CKD
Drug
CKD Considerations
Action
HCTZ, chlorthalidone LIMITED
Lose efficacy at eGFR < 30 (poor delivery to distal tubule).
Switch to loop diuretic at eGFR < 30. Metolazone is the only thiazide-like agent that retains effect at low GFR.
Metolazone CKD-FRIENDLY
Thiazide-like. Works at any GFR. Synergistic with loop diuretics.
Useful as add-on for diuretic resistance in CKD. Monitor K⁺, Mg, Na.
Work at any GFR but often need higher doses as CKD advances.
First-line diuretic at eGFR < 30 for both volume and BP. Torsemide preferred for outpatient (better PO bioavailability).
MRA (spironolactone, eplerenone) HYPERK RISK
Hyperkalemia risk rises sharply as eGFR drops.
Avoid at eGFR < 30. Caution 30-60 with frequent K⁺ monitoring (3 days, 1 week, monthly). Consider K-binder (patiromer, sodium zirconium) before discontinuing in CKD/HF overlap where the MRA is providing mortality benefit.
Acetazolamide CAUTION
Renally cleared, can worsen metabolic acidosis (already common in CKD).
Avoid or reduce. Not typically used for HTN anyway.
CCBs and other agents
Drug Class
CKD Considerations
Action
Amlodipine, felodipine, nifedipine ER (DHP CCBs) PREFERRED
Hepatically cleared.
Safe at any eGFR. No dose adjustment. Excellent first-line in CKD HTN.
Diltiazem, verapamil (non-DHP CCBs)
Hepatically cleared.
Safe in CKD. Avoid in HFrEF (negative inotropy).
Doxazosin, terazosin (alpha-blockers)
Hepatically cleared.
Safe in CKD. Useful add-on with BPH coexistence.
Hydralazine CKD-FRIENDLY
Hepatically cleared.
No renal adjustment. Useful in resistant HTN with CKD when other classes are limited.
Clonidine ADJUST
Renally cleared, accumulates in CKD.
Reduce dose. Patch is preferred for steady levels and adherence (avoids the rebound HTN problem).
Methyldopa
Renally cleared.
Mild adjustment. Mostly used in pregnancy.
Minoxidil
Hepatically cleared, but causes fluid retention and reflex tachycardia.
Reserved for severe resistant HTN with CKD on dialysis. Pair with loop diuretic + BB.
NSAIDs NEVER
Drive AKI, blunt BP control, worsen HTN. Even short courses precipitate AKI in CKD.
Avoid in CKD always. Use acetaminophen for pain.
AKI: Same Principles, More Urgent
AKI is a moving target. Atenolol's accumulation problem is worse in AKI than in stable CKD because you can't predict drug clearance as kidney function changes hour-to-hour, and AKI patients are usually hemodynamically labile (sepsis, post-op, volume shifts). The same logic applies to every renally cleared antihypertensive.
HTN drugs to HOLD when AKI develops on a hypertensive patient:
ACEi / ARB / ARNI -dilate the efferent arteriole and drop GFR further. Especially harmful in pre-renal AKI or bilateral RAS. Hold until Cr is stable, then resume cautiously.
Aliskiren -same problem as ACEi/ARB but worse. Always hold.
NSAIDs -constrict the afferent arteriole, drive AKI directly. Always off in AKI, even short courses.
Atenolol, nadolol, sotalol -accumulate unpredictably. Switch to a hepatic BB.
Spironolactone, eplerenone -hyperkalemia risk skyrockets when GFR drops acutely. Hold.
HCTZ / chlorthalidone -lose efficacy at low GFR anyway; switch to a loop if diuresis is needed.
Oral clonidine -accumulates; switch to patch (steady release, less rebound risk if doses missed).
Metformin (not HTN, but always check) -hold in any significant AKI to prevent lactic acidosis.
Safe to keep or start in AKI for HTN control:
Amlodipine -hepatic, no adjustment, safe at any GFR.
Hydralazine -hepatic, useful for resistant HTN in AKI when other classes are limited.
Hepatic BBs -metoprolol, carvedilol, labetalol. Switch from atenolol if patient was on it.
Loop diuretics if volume-overloaded; often need higher doses as AKI progresses.
IV options for severe HTN in AKI:nicardipine (DHP CCB), labetalol (alpha+beta blocker), esmolol (ultrashort BB, t½ ~9 min, hepatic clearance, ideal when you want the option to bail quickly).
One-line rule: If renal clearance is impaired for any reason -chronic (CKD) or acute (AKI) -atenolol accumulates and gets you in trouble. AKI is actually riskier than stable CKD because the kidney function is a moving target.
CKD HTN cheat sheet:
Proteinuria + CKD → ACEi or ARB first (renal-protective per AASK 2002).
Add SGLT2i for any CKD patient with eGFR > 20 - mortality and renal-protective regardless of diabetes (DAPA-CKD 2020).
Need a CCB → amlodipine, hepatically cleared and safe at any GFR.
Need a diuretic at eGFR < 30 → loop (furosemide / torsemide). Add metolazone if resistance.
Need a BB → metoprolol, carvedilol, or labetalol. Avoid atenolol, nadolol, sotalol.
Resistant HTN in CKD → spironolactone IF eGFR > 30 and K⁺ < 5.0; otherwise hydralazine, clonidine patch, or minoxidil.
Resistant HTN = BP above goal despite three drugs of different classes (one of which is a diuretic) at maximally tolerated doses, OR controlled BP requiring four or more drugs.
White-coat effect -confirm with home BP monitoring or ABPM.
Inadequate dosing -is each agent at maximal tolerated dose? Is the diuretic chlorthalidone (preferred) or HCTZ?
Wrong diuretic for renal function -loop diuretic is needed at eGFR < 30; thiazides lose efficacy (except metolazone).
Drug or substance contributors -NSAIDs, oral contraceptives, decongestants (pseudoephedrine), cocaine/amphetamines, glucocorticoids, licorice (mineralocorticoid mimic), erythropoietin, calcineurin inhibitors.
Step 2: Screen for Secondary Causes
Cause
Screening Test
Confirmatory
Primary aldosteronism (most common, ~5-13% of all HTN)
Morning aldosterone-to-renin ratio (ARR). ARR > 20-30 with aldosterone > 15 ng/dL. Hold MRA ≥ 4 weeks, ACEi/ARB/diuretics ≥ 2 weeks before testing.
Salt-loading test or saline suppression. Then adrenal vein sampling (gold standard) to localize unilateral vs bilateral. CT alone misses ~38% of unilateral disease.
Polysomnography (in-lab) or home sleep apnea testing. Treat with CPAP -modest BP reduction (3-5 mmHg).
Renovascular disease (atherosclerotic in older adult; fibromuscular dysplasia in young woman)
Renal artery duplex, MRA, or CTA. Suspect with abdominal bruit, flash pulmonary edema, AKI on ACEi/ARB.
CTA or MRA. Angiography if intervention planned. Stenting only if > 70% stenosis with refractory HTN or recurrent HF (CORAL, 2014 was negative for routine stenting in atherosclerotic RAS).
CKD
BMP, UACR. Often both cause and consequence of HTN.
Renal US for size and obstruction.
Pheochromocytoma
Plasma free metanephrines OR 24-hour urine fractionated metanephrines.
CT/MRI adrenals. Do NOT biopsy -triggers catecholamine crisis. Alpha-block (phenoxybenzamine) BEFORE beta-block.
If positive, ACTH-dependence assessment, then localize source.
Thyroid disease
TSH
Free T4 if abnormal.
Coarctation of aorta (young patient)
BP differential between arms and legs (legs lower). Radial-femoral pulse delay.
Echocardiogram, CTA aorta.
Step 3: Add the Right Fourth Drug
PATHWAY-2, 2015: Spironolactone is the preferred fourth-line agent for resistant HTN. Outperformed bisoprolol and doxazosin for BP reduction in patients on optimized A+C+D (ACEi/ARB + amlodipine + chlorthalidone).
Spironolactone 12.5-50 mg daily -fourth-line of choice. Watch K⁺ (especially with concomitant ACEi/ARB). Switch to eplerenone if gynecomastia.
Alternatives if spironolactone contraindicated or intolerable: bisoprolol (resting HR > 70), doxazosin (BPH coexists), or clonidine.
Renal denervation -SPYRAL HTN-ON MED, 2020 showed efficacy on top of optimized triple therapy (SBP ↓ 4-5 mmHg vs sham). FDA-approved (2023) for resistant HTN; modest overall benefit (~5-10 mmHg SBP reduction). Specialty referral.
📋 On Rounds
Pimp Questions
Why is chlorthalidone preferred over HCTZ?
Longer half-life (40-60h vs 6-15h for HCTZ) gives better 24-hour BP control, especially overnight. Multiple meta-analyses suggest greater CV event reduction at equipotent doses. Trade-off: higher rates of hypokalemia and hyponatremia, so monitor electrolytes more closely. Chlorthalidone 12.5-25 mg ≈ HCTZ 25-50 mg in BP-lowering effect.
Why isn't a beta-blocker first-line for uncomplicated HTN?
BBs lower BP but have weaker stroke reduction than thiazides, CCBs, or ACEi/ARB at equipotent BP-lowering. LIFE, 2002 (atenolol vs losartan in HTN with LVH) showed BBs underperformed for stroke prevention despite similar BP lowering. They're still first-line when there's a compelling indication (HFrEF, post-MI, AFib rate control), just not for HTN alone.
A 32-year-old woman has BP 168/104 with serum K⁺ 3.1. What's the diagnosis to consider?
Primary aldosteronism -unprovoked hypokalemia plus HTN should always trigger this consideration. It's the most common secondary cause (~5-13% of all HTN, often normokalemic). Workup: morning aldosterone-to-renin ratio (ARR), hold MR antagonists ≥ 4 weeks and ACEi/ARB/diuretics ≥ 2 weeks first. Confirm with salt-loading or saline suppression test, then adrenal vein sampling to localize.
What's the most common reason a patient appears to have resistant HTN?
Non-adherence -by far the #1 cause. Studies using directly-observed therapy or pill-counts show that 30-50% of "resistant" patients are simply not taking their medications. Other pseudoresistance causes: white-coat effect (use home/ABPM), inadequate dosing, wrong diuretic for renal function (need loop at eGFR < 30), and drug interactions (NSAIDs, OCPs, decongestants). Always rule out pseudoresistance before adding a fourth drug or chasing secondary causes.
What's the spironolactone evidence in resistant HTN?
PATHWAY-2, 2015: in patients with resistant HTN already on ACEi/ARB + CCB + thiazide, spironolactone reduced home SBP significantly more than bisoprolol or doxazosin. This established spironolactone as the preferred fourth-line agent. Mechanism: most resistant HTN involves some aldosterone-driven sodium retention, even without overt primary aldosteronism. Watch hyperkalemia (recheck K⁺ at 3 days, 1 week, then monthly).
Why avoid ACEi monotherapy in Black patients?
ALLHAT 2002 and other trials: ACEi monotherapy lowers BP less effectively in Black patients compared to non-Black. Mechanistic explanation: Black patients tend to have lower-renin HTN, which responds better to thiazides and CCBs (volume/vascular drivers) than to RAAS inhibition. ACEi/ARB are still appropriate when there's a compelling indication -concomitant HFrEF, CKD with proteinuria, or DM with albuminuria -but as monotherapy for uncomplicated HTN in Black patients, thiazide or CCB is preferred.
Clinical Examples
📋 Case 1, New Stage 2 HTN, No Comorbidities
Patient: 52F with no PMH presents for routine physical. BP 156/96 today, 152/94 last visit (2 weeks ago). Home BP averaging 150/92 over the past month. BMI 31. Non-Black. No DM or CKD.
Two-drug combination (BP > 20/10 above target): start chlorthalidone 12.5 mg + lisinopril 10 mg, ideally as a single-pill combination.
Follow-up at 2-4 weeks with BMP and BP recheck. Target home average < 130/80.
Teaching point: Stage 2 HTN warrants two drugs from day 1. Single-pill combinations dramatically improve adherence. Confirm diagnosis with home or ABPM data before committing to lifelong therapy.
📋 Case 2, Resistant HTN Workup
Patient: 58M, HTN ×8 years, on lisinopril 40 mg, amlodipine 10 mg, HCTZ 25 mg. Office BP 162/98 today. Home BP averages 158/96. Adherent (verified pill counts and pharmacy refills).
Pseudoresistance ruled out -adherent, home BP confirms, no offending drugs.
Switch HCTZ → chlorthalidone 25 mg for better 24h control.
Screen for secondary causes: morning aldosterone-to-renin ratio (low K⁺ raises suspicion for primary aldosteronism), STOP-BANG (BMI 34 high pretest for OSA), TSH.
Add spironolactone 25 mg daily as fourth agent (PATHWAY-2 evidence). Recheck K⁺ in 1 week.
Sleep study referral for OSA evaluation.
Teaching point: True resistant HTN demands secondary cause workup AND optimization of existing therapy (chlorthalidone over HCTZ). Spironolactone is the preferred fourth drug. Hypokalemia plus HTN should always raise primary aldosteronism on the differential.
📋 Case 3, HTN in Pregnancy
Patient: 29F, 22 weeks pregnant, BP 148/96 at routine prenatal visit. No proteinuria. No history of HTN. Asymptomatic.
Plan:
Recheck BP and confirm with home or repeat readings. Treat at threshold ≥ 140/90 per CHAP, 2022.
Workup: 24-hour urine protein or UACR (rule out preeclampsia), CBC, LFTs, BMP, uric acid.
Drug choice:labetalol (preferred) or nifedipine ER. Methyldopa is older alternative. Start labetalol 100 mg BID, titrate.
STOP any ACEi / ARB / ARNI / direct renin inhibitor -teratogenic, especially 2nd-3rd trimester (oligohydramnios, renal failure, skull defects).
OB co-management for preeclampsia surveillance.
Teaching point: Treat chronic HTN in pregnancy at 140/90 (CHAP 2022 changed practice). Labetalol, nifedipine, methyldopa are safe; RAAS inhibitors are absolutely contraindicated.
📣 Sample Presentation
One-Liner
"Mr. Lopez is a 58-year-old with stage 2 HTN, on triple therapy at maximum doses, with home BP averaging 158/96 despite verified adherence. Workup for resistant HTN today."
Plan
(1) Switch HCTZ to chlorthalidone. (2) Send aldosterone-to-renin ratio after holding MRA/diuretics for 2 weeks. (3) STOP-BANG and sleep study referral (BMI 34). (4) Add spironolactone 25 mg daily after K⁺ confirmed < 5.0. (5) Recheck BMP at 1 week, BP and home log at 4 weeks.
⚡ Summary
Summary
Confirm Before You Treat
Stage 1 is 130 to 139 or 80 to 89; stage 2 is 140/90 or above (ACC/AHA 2017).Confirm with out-of-office readings, home monitoring or ambulatory monitoring, before labeling anyone hypertensive.White coat hypertension is common, and masked hypertension is dangerous, so the clinic reading alone commits some patients to lifelong therapy they do not need and reassures others who do.
Start Drugs by Stage and Risk, Not by Number Alone
Stage 1 with ASCVD risk below 10%: lifestyle for 3 to 6 months.Stage 1 with risk 10% or above, or with diabetes, CKD or established cardiovascular disease: start medication.Stage 2: start two agents. Recheck and titrate at 2 to 4 weeks rather than at 3 months, since slow titration is why so many patients remain uncontrolled for years.
Four First-Line Classes, Chosen by Comorbidity
Thiazide, ACE inhibitor or ARB, and dihydropyridine calcium channel blocker.ACE inhibitor or ARB for diabetes with albuminuria, CKD and HFrEF.Beta blockers are not first line for uncomplicated hypertension, and are used when there is a compelling indication such as ischemic heart disease, heart failure or rate control. Never combine an ACE inhibitor with an ARB.
Prefer Chlorthalidone and Combine Rationally
Chlorthalidone is longer-acting and more potent than hydrochlorothiazide at equivalent doses.ACE inhibitor or ARB plus a calcium channel blocker beat ACE inhibitor plus thiazide on cardiovascular outcomes (ACCOMPLISH). Use single-pill combinations, which measurably improve adherence, and adherence is the dominant determinant of control.
Know Why SPRINT and ACCORD Split
SPRINT showed a systolic target below 120 reduced events and mortality in high-risk non-diabetic patients, using unattended automated readings that run lower than routine clinic values.ACCORD-BP found no benefit in diabetics.So an intensive target is reasonable in selected high-risk non-diabetic patients, measured the same way SPRINT measured it, and less so in diabetes and in the frail elderly where falls and syncope rise.
Non-Adherence Is the Number One Cause of Apparent Resistance
Before working up resistant hypertension, confirm the patient is actually taking the drugs and that the technique of measurement is correct: right cuff size, seated, back supported, arm at heart level, no talking. Pseudoresistance from non-adherence, white coat effect and poor technique accounts for a large share of referrals.
Screen for Secondary Causes in the Right Patients
Onset before 30 or after 55, resistant hypertension on three drugs including a diuretic, hypokalemia, an abrupt loss of control, or an adrenal mass.Primary aldosteronism is the commonest and is heavily under-diagnosed, and the 2025 guidance is to screen every hypertensive patient. Also consider renal artery stenosis, OSA, pheochromocytoma, thyroid disease, Cushing syndrome and coarctation.
Do Not Forget the Drug Causes and Lifestyle
NSAIDs, decongestants, oral contraceptives, stimulants, steroids, calcineurin inhibitors, licorice, alcohol and cocaine.Sodium restriction, the DASH diet, weight loss, exercise and alcohol reduction each lower systolic pressure by several mmHg and are additive, so together they are equivalent to a drug. Home blood pressure monitoring improves control and is a genuine intervention, not just a measurement.
First major update since 2018. Released March 13, 2026 by ACC/AHA with AACVPR/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA. Retitled from "Blood Cholesterol" to "Dyslipidemia" to reflect the broader scope (LDL + non-HDL + apoB + Lp(a) + remnants). Core principle: "lower LDL for longer is better" -cumulative exposure analogous to pack-years. Here is everything that changed from the 2018 guideline and why it matters for your practice.
⚖️ 2018 Cholesterol Guideline vs 2026 Dyslipidemia Guideline
Full Comparison Table
Domain
2018 ACC/AHA Cholesterol Guideline
2026 ACC/AHA/Multisociety Dyslipidemia Guideline
Impact
Risk Calculator
2013 Pooled Cohort Equation (PCE). Validated age 40-79, race input (Black / non-Black), 10-yr risk only.
PREVENT-ASCVD (Khan et al, Circulation 2024) replaces PCE. Validated age 30-79, race removed, adds eGFR / UACR (CKD), HbA1c, BMI, social deprivation index. Estimates 10-year AND 30-year ASCVD risk. Generally produces lower 10-yr estimates than PCE, especially in Black patients and the elderly.
New thresholds: low < 3%, borderline 3-< 5%, intermediate 5-< 10%, high ≥ 10%. Bands lowered to compensate for PREVENT producing lower scores than PCE -population qualifying for statin is roughly preserved, but the math is more equitable (no race input).
Major
Primary Prevention LDL Goal
No numeric LDL goal. Recommended "≥ 50% LDL reduction" with high-intensity statin in high-risk; "30-49%" with moderate-intensity in intermediate. No mg/dL target.
LDL < 70 mg/dL universally for clinical ASCVD. "Very-high-risk" (2018 / 2022 consensus) suggested < 55 but was less formally codified.
Split into two tiers, codified.Very-high-risk ASCVD → LDL < 55 mg/dL (apoB < 55). Standard-risk ASCVD (clinical ASCVD without VHR features) → LDL < 70. Lp(a) ≥ 50 mg/dL plus ASCVD newly added to the very-high-risk definition.
Major
Lp(a) Testing
"May be considered" as a risk enhancer in selected patients (FH, premature ASCVD family hx). Not routine.
Recommend Lp(a) measurement once per lifetime in all adults. Lp(a) ≥ 50 mg/dL (≥ 125 nmol/L) is a major risk enhancer. Lp(a) ≥ 50 + established ASCVD = "very-high-risk" → LDL goal < 55. Cascade-screen family. PCSK9i / inclisiran lower Lp(a) modestly (~15-25%); investigational siRNA/ASO agents are in trials.
Major
ApoB Testing
Listed as an optional risk enhancer; no quantitative target.
Routine measurement in patients with elevated TG (> 200), diabetes, low LDL on therapy, or borderline-risk decisions. Quantitative targets align with the LDL goal: apoB < 55 (when LDL goal is < 55, i.e., very-high-risk ASCVD), < 70 (when LDL goal is < 70, i.e., standard ASCVD or primary-prevention high-risk), < 90 (when LDL goal is < 100, i.e., primary-prevention intermediate / borderline categories). ApoB > the matched LDL target even when LDL appears at goal → intensify therapy (small-dense-LDL / remnant pattern).
Major
Early Intervention (young patients)
No formal "early intervention" category. Young patients with LDL 160-189 and no other risk factors mostly received lifestyle counseling unless severe (LDL ≥ 190 / FH).
NEW dedicated category. Start statin earlier when any of: HeFH at diagnosis (including children age 8-10), age ≤ 30 with LDL ≥ 160, strong family hx of premature ASCVD, or high 30-year PREVENT risk. Rationale: cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk; delaying treatment in young high-LDL patients wastes the longest-yield treatment window.
Major
Diabetes Statin Indication
DM age 40-75 with LDL 70-189 → moderate-intensity statin. High-intensity if ASCVD risk ≥ 7.5% or risk enhancers.
Expanded to age 30-39 when LDL ≥ 160 or elevated 30-year PREVENT risk. Intensification driven by 10-year PREVENT ≥ 10%, established ASCVD, or multiple risk enhancers. ADA-aligned LDL goal < 70 if ASCVD; < 100 otherwise.
Moderate
Heterozygous FH (HeFH)
High-intensity statin recommended; treatment age generally adult.
Treat at diagnosis regardless of age. Supports statin in HeFH children from age 8-10. Combination therapy (statin + ezetimibe → PCSK9i / inclisiran) initiated earlier to reach goal. Cascade screening of first-degree relatives reinforced.
Moderate
Non-Statin Add-On Strategy
Stepwise ladder: statin → ezetimibe → PCSK9i mAb. Inclisiran not yet approved at time of 2018 publication; bempedoic acid had limited outcomes data.
Reframed as parallel options. After max-tolerated statin: ezetimibe / bempedoic acid / PCSK9i mAb (alirocumab, evolocumab) / inclisiran. Choose by cost, route preference, comorbidities, adherence. Combination therapy is the rule, not the exception, for very-high-risk ASCVD -starting two or three agents simultaneously is now explicitly supported when far from goal.
Major
Bempedoic Acid
Limited mention; outcome data not yet available.
Formally included as a non-statin option, especially for statin-intolerant patients. Supported by CLEAR Outcomes, 2023 -13% MACE reduction in statin-intolerant patients. PO daily; muscle symptoms minimal; small ↑ in uric acid / gout risk.
New
Inclisiran (siRNA)
Not approved; not in 2018 guideline.
Now formally included. Small-interfering RNA targeting hepatic PCSK9 mRNA. SC every 6 months after loading dose. ~50% LDL reduction; major adherence advantage. ORION-10/11, 2020. CV outcomes trial (ORION-4) ongoing.
New
HIV Primary Prevention
Treat per general primary-prevention guidance (PCE-driven); no HIV-specific recommendation.
Pitavastatin 4 mg recommended for primary prevention in HIV adults age 40-75 regardless of standard LDL threshold. Driven by REPRIEVE, 2023 -35% MACE reduction over 5 yr in low-to-moderate-risk HIV patients with LDL below traditional treatment threshold. Avoid simvastatin / lovastatin with protease inhibitors (CYP3A4).
New
Hypertriglyceridemia (ASCVD)
Statin first; fish oil / fibrate roles modest. REDUCE-IT not yet published.
Icosapent ethyl 2 g BID recommended for patients with established ASCVD (or DM with risk factors) and persistent TG 150-499 on statin. REDUCE-IT, 2019: 25% MACE reduction. Fibrate-class CV benefit beyond statin disproven by PROMINENT, 2022; fenofibrate retained only for pancreatitis prevention at TG ≥ 500.
Moderate
Lifetime Exposure Framing
Risk-based framework with discrete decisions at index visit.
"Lower LDL for longer is better" codified as a guiding principle. Cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk; CTT meta-analysis: each ~39 mg/dL LDL drop ≈ 22% MACE reduction per year, compounding over time. Drives earlier starts and lower targets.
Moderate
Statin Intensity Definitions
High (≥ 50% LDL ↓), moderate (30-49%), low (< 30%) with specific drug-dose mapping.
Unchanged from 2018 -atorva 40-80 / rosuva 20-40 = high-intensity; atorva 10-20 / rosuva 5-10 = moderate. No new drug-dose tiers introduced.
Maintained
CAC Scoring
Tiebreaker for borderline 5-7.5% PCE; "powerdown" strategy (CAC = 0 → defer statin) supported in selected patients.
Tiebreaker for borderline 3-< 5% PREVENT (band shifted). Same role -confirms or downgrades risk in patients near the SDM threshold. CAC = 0 still supports deferring statin in select primary-prevention adults > 55 years without DM, FH, or smoking.
Moderate
Lipid Screening Age
Adults starting at age 20; repeat every 4-6 yr if normal.
Maintained. Adults starting at age 20; repeat every 4-6 yr if normal. New 2026 layer: measure Lp(a) once per lifetime, apoB in selected patients (see above).
Maintained
Fasting vs Non-Fasting
Non-fasting acceptable; fasting if TG > 400 needed for Friedewald.
Maintained. Non-fasting acceptable; redraw fasting if TG > 400. Friedewald LDL inaccurate at TG > 400 or LDL < 70 -use direct LDL or Martin-Hopkins method in those settings.
Maintained
🔥 Key Changes at a Glance
Bottom Line: The 2026 ACC/AHA/Multisociety Dyslipidemia Guideline shifts lipid management toward earlier, lower, longer. PREVENT-ASCVD replaces the 2013 PCE (no race input, ages 30-79, 10- and 30-year risk). Primary prevention gets numeric LDL goals for the first time (< 70 high-risk, < 100 intermediate). Secondary prevention is split into very-high-risk (< 55) vs standard-risk (< 70). Lp(a) is measured once per lifetime in all adults, apoB routinely in residual-risk patients. Non-statin therapies are parallel options rather than a strict ladder. A new early-intervention category formalizes statin starts in young high-LDL patients (HeFH, age ≤ 30 with LDL ≥ 160, strong family hx).
🚨 The 7 Biggest Changes
1. PREVENT replaces the Pooled Cohort Equation
PREVENT-ASCVD is now the recommended risk tool for primary prevention age 30-79. Removes race as input, adds CKD (eGFR / UACR), HbA1c, BMI, social deprivation. Estimates 10- and 30-year risk. Generally produces lower 10-yr scores than PCE -especially in Black patients and the elderly.
2. New Risk Bands
Low < 3% / borderline 3-< 5% / intermediate 5-< 10% / high ≥ 10%. Replaces the 2018 PCE bands (< 5 / 5-7.5 / 7.5-20 / ≥ 20%). Lowered to compensate for PREVENT producing lower scores -population qualifying for statin is roughly preserved.
Very-high-risk ASCVD → LDL < 55, apoB < 55. Standard-risk ASCVD → LDL < 70. Lp(a) ≥ 50 + ASCVD newly defined as very-high-risk. 2018 used < 70 universally; 2022 consensus first proposed < 55, codified in 2026.
5. Lp(a) and ApoB Become Routine
Lp(a) once per lifetime in all adults. ApoB routinely in patients with TG ≥150, DM, low LDL on therapy, or borderline-risk decisions. ApoB targets align with the LDL goal: < 55 (LDL goal < 55), < 70 (LDL goal < 70), < 90 (lower-risk / borderline).
6. Early-Intervention Category
NEW: formalizes earlier statin starts in HeFH at diagnosis (incl. children 8-10), age ≤ 30 with LDL ≥ 160, strong family hx of premature ASCVD, or high 30-year PREVENT. Rationale: cumulative LDL exposure ("LDL pack-years") drives lifetime risk -don't waste the longest-yield treatment window.
7. Non-Statin Add-Ons as Parallel Options
Reframed from strict ladder to parallel options: ezetimibe / bempedoic acid (CLEAR Outcomes 2023) / PCSK9i mAb / inclisiran (siRNA, SC q6mo). Choose by cost, route, comorbidity, adherence. Combination therapy is the rule, not the exception, for very-high-risk ASCVD -start two or three agents simultaneously when far from goal.
Several elements of the 2026 guideline did not exist in any form in 2018. These are the highest-yield "this is new" topics for board review and clinic.
📐 PREVENT 30-Year Risk Estimation
PCE only estimated 10-year risk. PREVENT estimates BOTH 10- and 30-year ASCVD risk. The 30-year horizon enables the new "early intervention" category -treat young patients with high lifetime exposure even when their 10-year score is low.
🎯 Numeric Primary-Prevention LDL Goals
For the first time in an ACC/AHA cholesterol guideline, primary prevention has explicit mg/dL targets: < 70 (high-risk) and < 100 (intermediate-risk). 2018 only specified percentage reductions without numeric goals. Aligns primary prevention with the secondary-prevention framework.
🧬 Routine Lp(a) Measurement
Once per lifetime in all adults. Genetic, doesn't change with lifestyle or statin. Lp(a) ≥ 50 mg/dL (≥ 125 nmol/L) = major risk enhancer. Lp(a) ≥ 50 plus established ASCVD = "very-high-risk" → LDL goal < 55. Cascade-screen first-degree relatives. PCSK9i and inclisiran lower Lp(a) modestly (~15-25%); investigational siRNA / ASO agents (pelacarsen, olpasiran, lepodisiran) in late-phase trials.
🧪 Routine ApoB Measurement
ApoB counts every atherogenic particle (one apoB per LDL, VLDL, IDL, Lp(a)). When LDL appears at goal but apoB exceeds it, the patient has small-dense-LDL or remnant-rich profile -still residual ASCVD risk. Targets align with the LDL goal: < 55 / < 70 / < 90 (matching LDL < 55 / < 70 / lower-risk respectively). 2018 mentioned apoB only as an optional risk enhancer.
🌱 Early-Intervention Category
Statin start before the traditional age-40 cutoff for any of: HeFH at diagnosis (including children 8-10), age ≤ 30 with LDL ≥ 160, strong family hx of premature ASCVD, or high 30-year PREVENT. Rationale: cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk -delaying treatment in young high-LDL patients wastes the longest-yield treatment window.
💊 Inclisiran (siRNA)
Small-interfering RNA targeting hepatic PCSK9 mRNA. SC injection at day 0, 90, then every 6 months. ~50% LDL reduction, sustained. Twice-yearly dosing is a major adherence advantage vs PCSK9 mAbs (q2-4 wk). ORION-10/11, 2020; CV outcomes trial (ORION-4) ongoing. Not in the 2018 guideline at all.
💊 Bempedoic Acid (Outcomes Data)
ATP-citrate lyase inhibitor; activated only in liver, not muscle (no myalgia). PO daily. CLEAR Outcomes, 2023: 13% MACE reduction in statin-intolerant patients with or at high risk for ASCVD. Now formally included in the 2026 ladder. Watch for ↑ uric acid / gout.
🦠 HIV Primary Prevention (REPRIEVE)
Pitavastatin 4 mg recommended in HIV adults age 40-75 regardless of standard LDL threshold.REPRIEVE, 2023: 35% MACE reduction over 5 yr. Avoid simva / lova with protease inhibitors (CYP3A4); pitavastatin or pravastatin preferred.
🐟 Icosapent Ethyl for Residual TG-Driven Risk
Icosapent ethyl 2 g BID for ASCVD (or DM with risk factors) and persistent TG 150-499 on statin. REDUCE-IT, 2019. Distinct from generic OTC fish oil (mixed EPA / DHA), which has not shown CV benefit. PROMINENT, 2022 closed the door on fibrate-class CV benefit beyond statin -fenofibrate retained for pancreatitis prevention at TG ≥ 500.
📜 "Lower for Longer" Mantra
First time codified as a guiding principle in an ACC/AHA cholesterol document. Cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk; CTT meta-analysis shows each ~39 mg/dL LDL drop ≈ 22% MACE reduction per year, compounding over time. Drives earlier starts and lower targets.
Key Trials Supporting the 2026 Changes
Trial
Year
Finding
2026 Impact
FOURIER
2017
Evolocumab on top of statin: 15% MACE reduction; safe down to LDL ~ 30
RoundsRx Infographic Series · #154 · Cardiovascular · PDF 157 KB
Text version
CARDIOLOGY · One Pager
2026 ACC/AHA Dyslipidemia Guideline: What Changed
First major update since 2018, and the whole document rests on one principle: lower LDL for longer is better, because cumulative exposure works like pack-years.
🧪 New Risk Tool and Bands
PREVENT-ASCVD replaces the 2013 Pooled Cohort Equation. Validated ages 30–79, race removed, adds eGFR / UACR, HbA1c, BMI, and social deprivation index, and estimates 10-year AND 30-year risk.
New bands: low <3%, borderline 3 to <5%, intermediate 5 to <10%, high ≥10%. Replaces <5 / 5–7.5 / 7.5–20 / ≥20%.
Why the bands dropped: PREVENT produces lower 10-year estimates than PCE, especially in Black patients and the elderly, so lowering the thresholds keeps roughly the same population eligible for statin while removing race from the math.
The 30-year horizon is what enables the new early-intervention category, since a young patient with high lifetime exposure can have a low 10-year score.
Lipid screening unchanged: adults from age 20, repeat every 4–6 years if normal. New layer on top is Lp(a) once per lifetime and apoB in selected patients.
Fasting rules unchanged: non-fasting acceptable, redraw fasting if TG >400. Friedewald is inaccurate at TG >400 or LDL <70, so use direct LDL or Martin-Hopkins there.
⚡ New LDL and ApoB Targets
Very-high-risk ASCVD: LDL <55 mg/dL (apoB <55). 2018 used <70 universally; the 2022 consensus proposed <55 and 2026 codified it.
Standard-risk ASCVD (clinical ASCVD without very-high-risk features): LDL <70.
Primary prevention, PREVENT ≥10%: LDL <70. Genuinely new, since 2018 had no numeric primary-prevention goal at all, only "≥50% reduction."
Primary prevention, PREVENT 5 to <10%: LDL <100. 2018 only said "30–49% reduction" with a moderate-intensity statin.
ApoB targets align with the LDL goal: <55 / <70 / <90, matching LDL goals of <55, <70, and <100 respectively. ApoB above the matched target even when LDL looks at goal means a small-dense-LDL or remnant pattern, so intensify therapy.
Lp(a) ≥50 mg/dL plus established ASCVD is newly added to the very-high-risk definition, which moves that patient from a <70 goal to a <55 goal.
🚨 The Seven Biggest Changes
1
PREVENT replaces the PCE: ages 30–79, no race input, adds CKD / HbA1c / BMI / social deprivation, gives 10-year and 30-year risk.
2
New risk bands: <3 / 3 to <5 / 5 to <10 / ≥10%, lowered to compensate for PREVENT scoring lower than PCE.
3
Numeric LDL goals in primary prevention for the first time: <70 if PREVENT ≥10%, <100 if 5 to <10%. This brings primary prevention into the same framework as secondary prevention.
4
Secondary prevention split into two tiers: very-high-risk gets LDL <55 and apoB <55, standard-risk stays at <70.
5
Lp(a) and apoB become routine: Lp(a) once per lifetime in all adults, apoB routinely when TG ≥150, diabetes, low LDL on therapy, or a borderline-risk decision.
6
New early-intervention category: HeFH at diagnosis including children age 8–10, age ≤30 with LDL ≥160, strong family history of premature ASCVD, or high 30-year PREVENT. Delaying treatment in a young high-LDL patient wastes the longest-yield treatment window.
7
Non-statin add-ons reframed as parallel options, not a strict ladder: ezetimibe / bempedoic acid / PCSK9i mAb / inclisiran, chosen by cost, route, comorbidity, and adherence. Combination therapy is the rule, not the exception, for very-high-risk ASCVD.
💊 Drugs New or Newly Positioned
Bempedoic acidPO daily; formally included, especially for statin-intolerant patients. Muscle symptoms minimal; watch uric acid and gout
Inclisiran (siRNA)SC every 6 months after loading; ~50% LDL reduction, major adherence advantage. Not in the 2018 guideline at all
PCSK9i mAbalirocumab or evolocumab; now a parallel option rather than the last rung of a ladder
Pitavastatin4 mg for primary prevention in HIV adults age 40–75 regardless of standard LDL threshold
Icosapent ethyl2 g BID for established ASCVD (or DM with risk factors) and persistent TG 150–499 on statin
Fenofibrateretained only for pancreatitis prevention at TG ≥500, because fibrate-class CV benefit beyond statin was disproven
📊 What Stayed the Same
Statin intensity definitions unchanged: atorvastatin 40–80 or rosuvastatin 20–40 is high-intensity, atorvastatin 10–20 or rosuvastatin 5–10 is moderate. No new drug-dose tiers.
Lipid screening from age 20, repeat every 4–6 years if normal.
Non-fasting panels remain acceptable, with a fasting redraw only if TG >400.
CAC keeps the same tiebreaker role, just in a shifted band: it now resolves the borderline 3 to <5% PREVENT group instead of borderline 5–7.5% PCE. CAC = 0 still supports deferring a statin in selected primary-prevention adults over 55 without diabetes, FH, or smoking.
⚠️ Pitfalls
Do not carry forward the old PCE bands. Calling 7.5% "intermediate" is a 2018 reflex; under PREVENT, 7.5% sits in the 5 to <10% intermediate band with an LDL goal of <100.
Do not apply a percentage rule to a patient with prior ASCVD. The <55 goal comes from feature-based very-high-risk classification, not from a risk score.
Do not quote a <65 or <80 apoB tier. The 2026 apoB scheme is <55 / <70 / <90, mapped to the LDL goal.
Do not substitute mixed omega-3 for icosapent ethyl. The outcome data belongs to icosapent ethyl.
Do not treat a normal LDL as the end of the assessment when apoB exceeds the matched target; that residual particle burden still carries ASCVD risk.
Do not avoid simvastatin or lovastatin questions in HIV. They interact with protease inhibitors via CYP3A4 and must be avoided.
🏥 Population-Specific Changes
Diabetes, EXPANDED: 2018 covered age 40–75; 2026 adds age 30–39 when LDL ≥160 or 30-year PREVENT is elevated. Intensification is driven by 10-year PREVENT ≥10%, established ASCVD, or multiple risk enhancers. Goal LDL <70 if ASCVD, <100 otherwise.
Heterozygous FH, EARLIER START: treat at diagnosis regardless of age, with statin supported in HeFH children from age 8–10. Combination therapy is started earlier to reach goal, and cascade screening of first-degree relatives is reinforced.
HIV, NEW: pitavastatin 4 mg for primary prevention in adults age 40–75 regardless of the standard LDL threshold.
Hypertriglyceridemia: icosapent ethyl 2 g BID for ASCVD or DM with risk factors and persistent TG 150–499 on statin; fenofibrate now only for pancreatitis prevention at TG ≥500.
Lp(a), MAJOR: measure once per lifetime in all adults. ≥50 mg/dL (≥125 nmol/L) is a major risk enhancer, and cascade screening of family follows. PCSK9i and inclisiran lower Lp(a) only modestly (~15–25%).
🎓 Key Evidence Behind the Changes
CTT meta-analysis, 2010 / 2015: each ~39 mg/dL LDL drop is about a 22% MACE reduction per year, compounding over time. This is the arithmetic behind "lower for longer."
FOURIER, 2017: evolocumab on top of statin cut MACE 15% and was safe down to LDL ~30, supporting lower targets.
REDUCE-IT, 2019: 25% MACE reduction, which is what codified icosapent ethyl for residual TG-driven risk.
ORION-10/11, 2020: ~50% LDL reduction sustained, bringing inclisiran into the 2026 options. CV outcomes trial ORION-4 is ongoing.
PROMINENT, 2022: pemafibrate lowered TG ~26% with no MACE reduction, which closed the door on fibrate-class CV benefit beyond statin.
CLEAR Outcomes, 2023: 13% MACE reduction in statin-intolerant patients, formally putting bempedoic acid on the list.
REPRIEVE, 2023: 35% MACE reduction over 5 years in HIV patients whose LDL sat below the traditional treatment threshold.
PREVENT (Khan et al), 2024: the race-free equations, ages 30–79, adding CKD / HbA1c / SDI with 10-year and 30-year output, that replaced the PCE.
CardiologyAmbulatoryCommon
Outpatient Lipid Management
2026 ACC/AHA/Multisociety Dyslipidemia Guideline (released March 13, 2026) is the current framework -retires the 2018 cholesterol guideline. Core principle: "lower LDL for longer is better" (cumulative exposure, analogous to pack-years). PREVENT-ASCVD risk replaces the 2013 Pooled Cohort Equation. Lower LDL targets (<55 very high-risk ASCVD, <70 standard ASCVD or high-risk primary prevention, <100 intermediate primary prevention), earlier statin starts (HeFH(heterozygous familial hypercholesterolemia), age ≤30 with LDL ≥160, strong family hx), routine apoB (apolipoprotein B) and Lp(a) (lipoprotein(a)). Statin → ezetimibe / bempedoic acid / PCSK9i mAb / inclisiran.
The PREVENT equations are now the recommended risk tool. Use the PREVENT calculator; new thresholds drive treatment.
10-yr PREVENT-ASCVD Risk
Category
2026 Recommendation
vs 2018 (Pooled Cohort Equation)
< 3%
Low
Lifestyle. Moderate-intensity statin may be considered if LDL 160-189 (severe hypercholesterolemia subgroup). Otherwise reassess in 4-6 yr.
2018 cutoff was <5% (low). Threshold tightened in 2026 because PREVENT scores run lower than PCE -keeps the same population on lifestyle-only.
3% to < 5%
Borderline
Lipid-lowering therapy may be considered after risk discussion. CAC scoring useful tiebreaker. Risk enhancers (FH, Lp(a) ≥ 50, CKD, premature family hx) tip toward starting.
2018 borderline was 5-7.5%. 2026 lowered the band to 3-<5% to compensate for PREVENT producing lower scores than PCE. Population qualifying is roughly similar.
5% to < 10%
Intermediate
Lipid-lowering should be considered. Moderate-intensity statin; LDL goal < 100 mg/dL. Add non-statin if not at goal.
2018 used 7.5-20% as "intermediate." 2026 added a numeric LDL goal here (<100) -2018 had none for primary prevention.
2018 high-risk was ≥20% (or 7.5-20% with enhancers → high-intensity). 2026 added <70 numeric LDL goal -2018 had no primary-prevention numeric goal at all.
Important calibration point: PREVENT generally produces lower 10-yr risk estimates than the 2013 PCE -especially in Black patients and the elderly -because it removes race and recalibrates to contemporary cohorts. Treatment thresholds were also lowered to compensate. The combination is roughly risk-neutral overall (similar populations qualify for statin), but the math is now more equitable.
Who Gets a Statin (2026 Indications)
The 2026 guideline reorganizes the old "4 statin benefit groups" into broader treatment indications. Same core decisions (ASCVD, severe LDL, DM, primary-prevention risk) but with new thresholds and a NEW "early intervention" category for young high-LDL patients.
▶ Primary vs secondary prevention -don't mix the rules (tap to expand)
The 2026 guideline uses different criteria for primary vs secondary prevention. The percentage-based rule (≥10%) only applies to primary prevention.
First question: Has the patient already had an ASCVD event (MI, stroke/TIA, coronary revasc, PAD with imaging)?
NO → Primary prevention. Calculate PREVENT 10-yr risk:
≥ 10% → high risk → LDL < 70
5 to < 10% → intermediate → LDL < 100
3 to < 5% → borderline → SDM, optional therapy
< 3% → lifestyle
YES → Secondary prevention.Do NOT use PREVENT -calculator is not validated post-event. Classify by clinical features:
Bottom line: LDL < 55 is reserved for very-high-risk ASCVD (a feature-based classification, no percentage gate). Primary prevention tops out at LDL < 70 (PREVENT ≥ 10%) -the percentage rule never produces a < 55 goal. Don't apply the ≥ 10% rule to a patient with prior ASCVD -PREVENT isn't validated post-event; classify them by clinical features instead.
High-intensity regardless of risk. Goal LDL reduction ≥ 50%. Add ezetimibe / bempedoic acid → PCSK9i / inclisiran early. Treat all HeFH(heterozygous FH)starting at diagnosis (2026 emphasis: don't delay). Children with HeFH: consider statin from age 8-10.
Same indication as 2018. EARLIER START 2026 emphasizes treating HeFH at diagnosis (incl. children 8-10) rather than delaying to adulthood.
3. Primary prevention by PREVENT risk
Adult age 30-79 with LDL 70-189, no DM, no prior ASCVD event. Use this row only if rows 1-2 and 4-5 don't apply. The criteria are exclusion gates: age <30 → row 5, LDL ≥190 → row 2, DM → row 4, prior ASCVD → row 1, LDL <70 → no statin needed. PREVENT score then drives intensity.
CHANGED Major restructure: 2018 was age 40-75 with PCE thresholds (<5/5-7.5/7.5-20/≥20%). 2026 is age 30-79 with PREVENT thresholds (<3/3-<5/5-<10/≥10%). 2018 had no numeric primary-prev LDL goal; 2026 added <70 high / <100 intermediate.
4. Diabetes
DM age 40-75 with LDL 70-189; consider age 30-39 if LDL ≥ 160 or elevated 30-yr PREVENT risk
Moderate-intensity baseline. High-intensity if PREVENT risk ≥ 10%, multiple risk enhancers, or established ASCVD. Goal LDL < 70 if ASCVD; < 100 otherwise. Evidence:CARDS, 2004 · HPS-DM
2018 was age 40-75 only. EXPANDED 2026 added age 30-39 with LDL ≥ 160 or elevated 30-yr PREVENT. Intensification trigger now PREVENT ≥ 10% (was ASCVD ≥ 7.5% in 2018).
5. Early intervention NEW 2026
HeFH at any age, age ≤ 30 with LDL ≥ 160, strong family hx of premature ASCVD, high 30-yr PREVENT risk
Start statin earlier than the traditional age-40 cutoff. Rationale: cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk; delaying treatment in young high-LDL patients wastes the longest-yield treatment window.
NEW 2026 2018 had no formal "early intervention" category. Young patients with LDL 160-189 and no other risk factors mostly got lifestyle. 2026 enabled by PREVENT 30-yr risk estimation.
Lipid therapy is one piece of secondary prevention -don't forget aspirin.ASA 75-100 mg daily (typically 81 mg) is universally indicated for all secondary prevention of ASCVD: prior MI, ischemic stroke / TIA (non-cardioembolic), stable angina, PAD with imaging, post-CABG / PCI. Evidence: ATT, 2002 showed ~22% MACE reduction across all secondary-prevention subgroups. Exceptions: active major bleeding, severe thrombocytopenia, true ASA allergy. On full anticoagulation for AFib + stable ASCVD? Often drop ASA after 12 mo of triple therapy (AUGUSTUS, 2019; WOEST, 2013) -DOAC + clopidogrel monotherapy is the new standard for that combination. Primary prevention? ASA is no longer routinely recommended (ASPREE, 2018; ARRIVE, 2018).
"Very High-Risk ASCVD" (drives the <55 LDL goal)
2026 retains the very-high-risk ASCVD category from the 2018 framework / 2022 consensus. Defining it matters because it triggers the more aggressive LDL goal (<55 mg/dL with apoB <55) and earlier non-statin add-on.
Multiple major ASCVD events (e.g., recurrent MI, MI + stroke, MI + symptomatic PAD)
One major ASCVD event PLUS multiple high-risk conditions: age ≥ 65, HeFH, prior CABG/PCI outside the index event, DM, HTN, CKD (eGFR 15-59), smoking, persistent LDL ≥ 100 on max-tolerated statin + ezetimibe, history of HF
When PREVENT risk is borderline, these factors push toward statin treatment. Document at least one before starting therapy in this group. (Same list as 2018, with 2026 emphasis on Lp(a) and CKD.)
Family history of premature ASCVD (men < 55, women < 65 in first-degree relative)
Persistent LDL ≥ 160 (even before statin) or non-HDL ≥ 190
Chronic kidney disease (eGFR 15-59, or albuminuria)
Avoid simvastatin 80 mg. FDA black-box -higher rhabdomyolysis risk than other statins at equipotent doses. If a patient was at 80 mg before March 2010 without issues, they can stay; otherwise switch to atorvastatin or rosuvastatin.
LDL Targets by Population (2026 ACC/AHA Dyslipidemia Guideline)
Population
2026 LDL Target
vs 2018 Cholesterol Guideline
ApoB Target / Trigger to intensify
Very high-risk ASCVD (recurrent event, polyvascular disease, ≥1 major event + multiple high-risk conditions, FH + ASCVD, or Lp(a) ≥ 50 + ASCVD)
< 55 mg/dL ≥ 50% reduction from baseline
2018 had <70. CHANGED AHA 2022 consensus first proposed <55 for this group; 2026 codified it. Lp(a) ≥ 50 + ASCVD newly added to definition in 2026.
apoB < 55 mg/dL. Add PCSK9i / inclisiran if LDL ≥ 70 on max statin + ezetimibe / bempedoic acid.
Standard-risk ASCVD (clinical ASCVD without very-high-risk features)
< 70 mg/dL ≥ 50% reduction
2018 also < 70. UNCHANGED
apoB < 70 (matches LDL goal). Add ezetimibe / bempedoic acid if > 70 on max statin; PCSK9i / inclisiran if still not at goal.
Primary prevention -high risk (PREVENT ≥ 10%)
< 70 mg/dL or ≥ 50% reduction
2018 had no numeric primary-prevention LDL goal (only "≥50% reduction"). NEW 2026
High-intensity statin baseline. Add non-statin if not at goal.
Primary prevention -intermediate risk (PREVENT 5 to < 10%)
< 100 mg/dL or ≥ 30-49% reduction
2018 had no numeric goal; just "30-49% reduction" with moderate statin. NEW 2026
Moderate-intensity statin baseline.
Primary prevention -borderline risk (PREVENT 3 to < 5%)
If treated: < 100 (or ≥ 30% reduction)
2018 borderline band was 5-7.5%; 2026 shifted to 3-<5% to compensate for PREVENT producing lower scores. CHANGED
"Lower for longer is better" -central principle of the 2026 guideline. Cumulative LDL exposure ("LDL pack-years") drives lifetime ASCVD risk. CTT meta-analysis showed each ~39 mg/dL LDL drop yields ~22% MACE reduction per year, compounding over time. FOURIER / ODYSSEY OUTCOMES confirmed safety down to LDL ~20-30 mg/dL. Implication: earlier and more aggressive LDL reduction yields more lifetime benefit -hence the 2026 emphasis on starting young high-LDL patients sooner and pushing primary-prevention targets lower.
🧪 Workup
When to Screen
2026 ACC/AHA Dyslipidemia Guideline: screen all adults starting at age 20 with a fasting or non-fasting lipid panel. Repeat every 4-6 yr if normal; more frequently if borderline or treated. NEW 2026: measure Lp(a) once per lifetime in all adults and apoB in patients with elevated TG, DM, low LDL on therapy, or borderline-risk decisions.
USPSTF 2022: statin initiation recommended for adults 40-75 with ≥ 1 CV risk factor and 10-yr ASCVD risk ≥ 10% (still in effect; 2026 ACC/AHA goes further with PREVENT-based thresholds).
Children (rare): universal screening once between ages 9-11 and again 17-21 (NHLBI 2011). Targeted earlier if family history of premature ASCVD or hypercholesterolemia. HeFH children: 2026 supports statin from age 8-10.
Special situations trigger earlier screening: family history of premature ASCVD, FH suspicion, xanthomas, premature CAD/stroke, pancreatitis (TG concern), DM, CKD, autoimmune disease, HIV.
Fasting vs Non-Fasting
Non-fasting lipid panel is acceptable for screening per the 2026 ACC/AHA Dyslipidemia Guideline (carried forward from 2018 ACC/AHA and ESC 2019). The exception: if non-fasting triglycerides > 400 mg/dL, repeat fasting for accurate LDL calculation (Friedewald equation fails at high TG).
Total cholesterol, HDL, direct LDL -minimally affected by fasting state
Triglycerides -increase 20-30% non-fasting; redraw fasting if > 400
Friedewald equation: LDL = TC - HDL - (TG / 5). Inaccurate when TG > 400 or LDL < 70 -use direct LDL or Martin-Hopkins method.
Children, post-MI acute, severe illness: fasting preferred for accuracy.
Initial Labs at Diagnosis
Test
Reason We Check
What It Changes
Fasting lipid panel (TC, LDL, HDL, TG, non-HDL)
Establish baseline + PREVENT calculator inputs
Drives statin initiation and intensity. Non-HDL = TC − HDL (more accurate than LDL when TG ≥150; goal = LDL goal + 30).
Lp(a) ONCE per lifetimeROUTINE 2026
Genetic risk factor; doesn't change with lifestyle/statin. 2026 guideline upgraded this to routine adult measurement.
Lp(a) ≥ 50 mg/dL (or ≥ 125 nmol/L) is a major risk enhancer. Pushes borderline patients toward statin. Lp(a) ≥ 50 + ASCVD = "very high-risk" classification (LDL goal < 55). Cascade-screen family. PCSK9i and inclisiran modestly lower Lp(a) ~25%; apheresis for refractory.
ApoBROUTINE 2026
Atherogenic particle count. 2026 emphasis: useful when LDL goal met (especially TG ≥150, DM, or LDL < 70).
Targets (mirror the LDL goal): apoB < 55 in very-high-risk ASCVD; < 70 in standard-risk ASCVD or high-risk primary prevention; < 90 in intermediate / borderline primary prevention. ApoB > LDL goal even when LDL "looks OK" → intensify therapy (small dense LDL pattern).
BMP / eGFR
CKD is a risk enhancer + drug-safety baseline
eGFR < 60 = CKD = risk enhancer. Statin choice: pravastatin or atorvastatin OK without renal adjustment; rosuvastatin reduce dose at eGFR < 30.
HbA1c / fasting glucose
Diabetes is a major statin indication
If DM diagnosed, automatically falls into the moderate-to-high intensity statin group regardless of PREVENT score.
TSH
Hypothyroidism is the #1 reversible secondary cause of hypercholesterolemia
Untreated hypothyroidism → high LDL; treat thyroid before initiating statin (LDL often normalizes on levothyroxine alone).
LFTs (ALT, AST)
Baseline before statin (severe liver disease is a relative contraindication)
Mild elevation isn't a contraindication. NAFLD/MASLD is common and statins are generally safe (and may help). Avoid statin only if active hepatitis or cirrhosis with decompensation.
CK (only if myalgia or risk factors for myopathy)
Baseline before statin in select patients
Routine CK before statin not recommended. Check at baseline only if hx of myopathy, on multiple statins, or high-risk drug interactions.
UACR (selected)
Albuminuria suggests CKD risk enhancer
UACR ≥ 30 in a non-DM patient → CKD as risk enhancer; pushes toward statin.
Workup for Severe Hypercholesterolemia (LDL ≥ 190)
LDL ≥ 190 is presumed familial hypercholesterolemia (FH) until proven otherwise. Heterozygous FH affects ~1 in 200-500 -much more common than most providers realize.
Family history: premature ASCVD (M < 55, F < 65) in first-degree relatives, hypercholesterolemia in family
TG ≥ 1000 = pancreatitis risk. Triggers urgent treatment with fibrate, omega-3, and lifestyle. TG ≥ 500 is the threshold for pharmacologic treatment to prevent pancreatitis.
Acute pancreatitis triggered by hypertriglyceridemia: treat with insulin drip + heparin (if not bleeding) or apheresis for severe cases. Long-term: fibrate + icosapent ethyl + dietary fat restriction.
🚨 Management
▶ How to Escalate Lipid Therapy, Step by Step (tap to expand)
2026 paradigm shift: non-statin therapies are no longer a strict ladder (statin → ezetimibe → PCSK9i over many years). They're parallel options. For high-risk patients far from goal, combination therapy from day 1 is now explicitly supported, "lower for longer" is the framing. Each 39 mg/dL LDL drop ≈ 22% MACE reduction per year (CTT meta-analysis); waiting six weeks at each step costs treatment time.
Step 1: Identify the indication
Bucket
Trigger
Starting Intensity
Secondary prevention (clinical ASCVD)
Prior MI, stable angina, coronary revasc, ischemic stroke/TIA, PAD with imaging
High-intensity statin always. LDL goal < 55. No PREVENT calculation needed, eligibility is the diagnosis.
Severe hypercholesterolemia (presumed FH)
Untreated LDL ≥ 190
High-intensity statin always. Treat HeFH at diagnosis, even children at age 8-10. Goal LDL < 70 (or < 55 if also clinical ASCVD).
DM age 40-75
Any T1DM or T2DM
Moderate-intensity baseline; high-intensity if established ASCVD, PREVENT ≥ 10%, or multiple risk enhancers.
Stacked: 20-30% LDL drop, comparable to a moderate-intensity statin. Always reinforced regardless of drug step.
Why start strong, not titrate up: each year on suboptimal LDL is a year of missed plaque-regression benefit. The 2026 "lower for longer" framing explicitly opposes starting low and creeping up unless intolerance forces it. Modify drug choice (rosuvastatin vs atorvastatin), not the intensity tier, for special populations: Asian descent (start rosuvastatin 5 mg), eGFR < 30 (rosuvastatin max 10 mg), HIV on PI (avoid simva/lova), cyclosporine (pravastatin/pitavastatin), pregnancy (stop all statins).
Step 3: Recheck at 4-12 weeks
Sweet spot is 6-8 weeks, statins reach steady-state nadir at ~4 weeks, so anything earlier risks false non-response. Measure LDL ± apoB ± non-HDL-C. Verify ≥ 50% LDL drop from baseline (high-intensity) or 30-49% (moderate). Don't routinely check LFTs (FDA dropped routine monitoring in 2012) or CK unless symptomatic. If LDL drop is < expected: check adherence first, ~50% of patients discontinue statins within a year, often without telling you.
Step 4: Not at LDL/apoB goal? Add a non-statin in parallel
Drug
When / Why
LDL Drop
Ezetimibe (Zetia) 10 mg PO daily USUAL 1ST ADD-ON
Cheap (generic), oral, easy. IMPROVE-IT (2015) showed CV benefit when added to statin in post-ACS. Default first add-on in most pathways.
~15-25% additional
PCSK9 monoclonal Ab (evolocumab, alirocumab) SC q2-4 wk
Far-from-goal patients, ASCVD with LDL still ≥ 70 on statin + ezetimibe, FH. Largest absolute LDL drop available. FOURIER (2017), ODYSSEY (2018).
~50-60% additional
Inclisiran (Leqvio) SC at month 0, 3, then q6 months
Adherence advantage, 2 injections per year. For patients who can't manage q2-4 wk SC. CV outcome data pending (ORION-4).
~50% additional
Bempedoic acid (Nexletol) 180 mg PO daily STATIN-INTOLERANT
Statin-intolerant patients (true myopathy, not nocebo). Oral. CLEAR Outcomes (2023): 13% MACE reduction in statin-intolerant patients.
~17-25% additional
For very-high-risk patients (recent ACS, multivessel ASCVD, recurrent events) starting far from goal: the 2026 guideline now supports initiating statin + ezetimibe simultaneously on day 1, or even statin + ezetimibe + PCSK9i in extreme cases, rather than the old sequential 6-week-recheck cascade. Don't lose treatment time waiting.
Step 5: Triglyceride pathway (parallel, not after LDL)
TG Level
Do This
Why
150-499 on statin, ASCVD or DM with risk
Add icosapent ethyl (Vascepa) 2 g BID
REDUCE-IT (2019): 25% MACE reduction. Don't substitute combination omega-3 (EPA+DHA), only icosapent ethyl has the outcome data.
Pancreatitis prevention is the indication for the fibrate, NOT MACE reduction. Use fenofibrate (not gemfibrozil) when combining with statin, gemfibrozil inhibits statin glucuronidation and raises rhabdo risk.
Fibrate-class skepticism (post-2022):PROMINENT (2022) showed pemafibrate lowered TG ~26% but produced NO MACE reduction in DM patients on statin. Fibrate role today is pancreatitis prevention at TG ≥ 500, not ASCVD risk reduction. For ASCVD + residual TG-driven risk, use icosapent ethyl.
Shortcuts that override the ladder
Scenario
Do This
Why
Recent ACS / very-high-risk ASCVD with LDL still > 100
Initiate high-intensity statin + ezetimibe together; consider PCSK9i upfront if LDL very far from goal
2026 guideline shift: combination therapy from day 1 for very-high-risk, not sequential.
True statin intolerance (documented myopathy on 2+ statins at low dose, CK or rhabdo, not nocebo)
Switch to bempedoic acid ± ezetimibe ± PCSK9i
CLEAR Outcomes proved bempedoic acid reduces MACE in this population. Try lower dose of a different statin first (rosuvastatin 5 mg every other day) before declaring intolerance.
Pregnancy
STOP all statins; resume after delivery and breastfeeding
Teratogenic. Bile acid sequestrants (cholestyramine) are the only LDL-lowering option in pregnancy if absolutely needed.
HoFH (homozygous familial hypercholesterolemia, LDL often > 500)
No Lp(a)-specific drug is approved yet (pelacarsen, olpasiran in trials). PCSK9i is the only currently-available lipid drug that lowers Lp(a). Niacin and aspirin are no longer recommended for Lp(a) alone.
Frail elderly with limited life expectancy
Consider one tier lower than indicated intensity, or deprescribe; SDM
Polypharmacy risk and competing mortality may outweigh CV benefit at advanced age. Not an absolute rule, individualize.
CV benefit far outweighs (~1 DM case per 1000 patient-years vs major MACE reduction). Patients at risk are usually already pre-diabetic.
Muscle symptoms without CK elevation (most "statin myalgia")
Trial off → rechallenge same statin, or switch to a different statin at lower dose, or alternate-day dosing of rosuvastatin
SAMSON (2020): ~90% of statin-attributed symptoms are nocebo (placebo arm and statin arm had identical symptom rates). Don't abandon the drug class on the first complaint.
▶ Lifestyle Interventions (always first or concurrent)
HDL increases ~5 mg/dL within 3 weeks. Major MACE benefit independent of lipids.
Alcohol moderation
↓ TG significantly
Heavy alcohol drives TG; even modest reduction helps. Avoid completely if TG > 500.
Stacking lifestyle changes (Mediterranean + saturated fat reduction + fiber + exercise + weight loss) can drop LDL by 20-30% -comparable to a moderate-intensity statin.
2026 Statin Initiation Algorithm
Identify the indication: clinical ASCVD, severe LDL ≥ 190, DM, primary prevention by PREVENT, or 2026 early-intervention category (HeFH / age ≤ 30 with LDL ≥ 160 / strong family hx). If none → lifestyle, reassess in 4-6 yr.
Calculate PREVENT 10-yr risk (and 30-yr if young) using the PREVENT calculator. Categorize: low / borderline / intermediate / high.
Choose intensity by 2026 thresholds:
Intensity
2026 indication (any of)
Default drug + dose
High-intensity ≥ 50% LDL ↓
Clinical ASCVD (any: MI, stable angina, coronary revasc, stroke/TIA, PAD with imaging) -secondary prevention is always high-intensity
LDL ≥ 190 (presumed FH; treat HeFH at diagnosis, age 8-10 in children)
DM with high-risk features: established ASCVD, PREVENT ≥ 10%, or multiple risk enhancers
PREVENT < 3% AND no DM, no clinical ASCVD, LDL < 190. Reassess in 4-6 yr. Consider moderate-intensity if LDL 160-189 (severe hypercholesterolemia subgroup).
,
Start at the indicated intensity -don't titrate up. Each ~39 mg/dL LDL drop ≈ 22% MACE reduction per year (CTT meta-analysis); starting low and creeping up wastes treatment time. The 2026 "lower for longer" framing explicitly supports starting strong from day 1. Step down only for documented intolerance.
Modify drug choice (not intensity tier) for special populations:
Asian patients -more sensitive to rosuvastatin; start 5 mg per FDA labeling (esp. Japanese descent)
eGFR < 30 -rosuvastatin max 10 mg; pravastatin or atorvastatin preferred (no renal dose adjustment needed)
HIV on protease inhibitor -avoid simvastatin / lovastatin (severe CYP3A4 interactions); use pravastatin, pitavastatin, or rosuvastatin
Transplant on cyclosporine -pravastatin or pitavastatin at low dose; avoid simva / lova
Pregnancy -STOP all statins (teratogenic). Resume after delivery / breastfeeding.
Frail elderly with multiple comorbidities -consider one tier lower than the indicated intensity; weigh life expectancy and polypharmacy risk
Start atorvastatin or rosuvastatin -most potent, generic, well-tolerated. Atorvastatin 40-80 mg or rosuvastatin 20-40 mg for high-intensity; atorvastatin 10-20 or rosuvastatin 5-10 for moderate.
Counsel: lifelong therapy, myalgia possible (low rate), nocebo effect common. Frame around "lower for longer" -longer treatment = more benefit.
Recheck lipid panel in 4-12 weeks: measure LDL ± apoB ± non-HDL-C. Verify adherence and ≥ 30-50% LDL drop.
If not at LDL / apoB goal: confirm adherence and max-tolerated statin → add non-statin in parallel options (2026 reframing): ezetimibe (PO, cheap), bempedoic acid (PO, statin-intolerant alternative), PCSK9 mAb (SC q2-4 wk, fastest LDL drop), or inclisiran (SC q6mo, adherence advantage). Choice driven by cost, route preference, comorbidities.
Recheck in 4-12 weeks after each escalation. Combination therapy is the rule, not the exception, for very-high-risk ASCVD.
2026 framing shift: non-statin therapies are no longer a strict ladder (statin → ezetimibe → PCSK9i). They are parallel options. For a high-risk patient starting far from goal, jumping straight to statin + ezetimibe + PCSK9i / inclisiran (or initiating combination at start) is now explicitly supported -don't lose treatment time waiting for 6-week rechecks at each step.
Hypertriglyceridemia Management
Triglyceride Level
Action
< 150 mg/dL
Normal. Lifestyle continues.
150-499 (mild-moderate)
Statin first (also lowers TG modestly). Address secondary causes (DM, alcohol, weight). If clinical ASCVD, or DM with risk factors and TG persistently 150-499 on statin (high PREVENT risk): add icosapent ethyl 2 g BID (REDUCE-IT, 2019).
500-999
Fibrate first (fenofibrate 145 mg daily) to prevent pancreatitis. Statin still indicated for ASCVD risk if criteria met. Add icosapent ethyl. Aggressive lifestyle.
Avoid gemfibrozil with statins -inhibits statin glucuronidation, increasing rhabdomyolysis risk significantly. Use fenofibrate instead when combining with a statin.
Fibrate-class skepticism (post-2022):PROMINENT, 2022 showed pemafibrate lowered TG ~26% but produced NO MACE reduction in DM patients on statin. Combined with prior negative ACCORD-Lipid, 2010, fibrate-class CV benefit beyond statin is largely disproven. Fenofibrate role today: pancreatitis prevention at TG ≥ 500, not ASCVD risk reduction. For ASCVD + residual TG-driven risk on statin, use icosapent ethyl (REDUCE-IT) instead.
Follow-up Cadence
After starting or changing therapy: recheck lipid panel in 4-12 weeks (sweet spot 6-8). This is when the ≥ 50% LDL-reduction goal is measured -drug reaches steady-state nadir by ~4 weeks, so don't recheck earlier (risk of falsely concluding non-response). Liver enzymes only if symptoms or hx of liver disease.
Stable on regimen at goal: annual lipid panel.
Don't routinely check CK unless myalgia. Don't routinely check LFTs unless symptoms or specific concern (FDA dropped routine LFT monitoring in 2012).
Adherence is key: ~50% of patients discontinue statins within 1 year. Re-engage with myalgia management, dose-adjustment, alternative regimens before declaring failure.
💊 Medications
Statins (foundation)
Drug
Dose
Notes
Atorvastatin (Lipitor) PREFERRED
10-80 mg PO daily (any time of day)
Most-prescribed statin. Hepatic clearance (CYP3A4) -watch interactions with macrolides, azoles, amiodarone, diltiazem, verapamil, grapefruit. Safe in CKD (no renal dose adjustment).
Rosuvastatin (Crestor) PREFERRED
5-40 mg PO daily
Most potent per mg. Minimal CYP3A4 metabolism -fewer drug interactions. Reduce dose at eGFR < 30 (max 10 mg). Asian patients more sensitive (start 5 mg).
Pravastatin (Pravachol)
10-80 mg PO daily
Hydrophilic, minimally metabolized by CYP -safest interaction profile. Useful in HIV (PI interactions), transplant patients on cyclosporine. Less potent.
Simvastatin (Zocor) AVOID 80 mg
10-40 mg PO at bedtime
Avoid 80 mg dose -FDA black-box for rhabdomyolysis. Many drug interactions (CYP3A4). Cheap.
Pitavastatin (Livalo)
1-4 mg PO daily
Newer, minimal CYP3A4 metabolism, preferred in HIV (lopinavir/ritonavir). More expensive.
Lovastatin, Fluvastatin
20-80 mg daily
Older, less commonly used.
▶ Choosing within high-intensity: atorvastatin 40 vs 80 mg (or rosuvastatin 20 vs 40)
Default to atorvastatin 40 mg (or rosuvastatin 20 mg) for high-intensity start. Reserve 80 mg (or rosuva 40 mg) for ACS/post-MI, very-high-risk ASCVD, or LDL not at goal on the lower dose at 4-12 weeks.
Scenario
Atorva dose
Why / Evidence
ACS / post-MI (within 30 days)
80 mg
PROVE-IT, 2004 -atorva 80 cut MACE 16% vs prava 40 post-ACS (LDL 62 vs 95). MIRACL, 2001 supported in-hospital initiation. Standard post-ACS protocol = atorva 80.
80 mg amplifies CYP3A4 interactions. Rosuvastatin has minimal CYP3A4 metabolism -safer choice if interactions are unavoidable.
Why not always 80? The atorva dose-response curve flattens at the top. 40 → 80 only adds ~6% more LDL reduction, but myalgia rate roughly doubles and adherence drops. Most landmark primary-prevention trials used moderate doses (CARDS atorva 10, ASCOT-LLA atorva 10, JUPITER rosuva 20). The 80 mg evidence base comes specifically from post-ACS / stable CAD secondary prevention trials (PROVE-IT, TNT, IDEAL).
Rosuvastatin 20 vs 40: rosuva 20 mg is the high-intensity default (potency ≈ atorva 40-80). Rosuva 40 reserved for the same scenarios as atorva 80 -more albuminuria / myalgia signal at 40 than 20. Many clinicians stop at rosuva 20 and add ezetimibe rather than push to 40 (better tolerated). Asian patients (esp. Japanese descent) -start rosuva 5 mg per FDA labeling.
▶ Choosing within moderate-intensity: which statin and which dose
Default to atorvastatin 10-20 mg or rosuvastatin 5-10 mg. The other moderate-intensity options exist for specific reasons -drug interactions, transplant patients, HIV on protease inhibitors, or cost. Use them when the default has a problem; don't use them by habit.
Scenario
Preferred drug + dose
Why
Default starting choice (most patients)
Atorvastatin 10-20 mg or rosuvastatin 5-10 mg
Most potent per mg, both generic, well-tolerated, atorva any time of day. Atorva 20 → ~38% LDL drop; rosuva 10 → ~43%.
HIV on protease inhibitor (lopinavir, ritonavir, atazanavir + ritonavir)
Pravastatin 40-80 mg or pitavastatin 1-4 mg
Avoid simvastatin / lovastatin (severe CYP3A4 interactions → rhabdo risk). Pravastatin is hydrophilic, minimally CYP-metabolized. Pitavastatin similar profile, more expensive. Rosuva is also acceptable.
Transplant on cyclosporine
Pravastatin 20-40 mg or pitavastatin 1-2 mg (low-dose)
Cyclosporine raises statin levels; pravastatin / pitavastatin minimize this. Avoid simvastatin and lovastatin. Atorva/rosuva can be used at reduced doses.
Both have minimal CYP3A4 metabolism. Switch from atorva/simva when interactions are unavoidable.
Asian patients (esp. Japanese descent)
Rosuvastatin 5 mg start (per FDA labeling)
Polymorphisms in OATP1B1 / SLCO1B1 increase rosuvastatin exposure. Start 5 mg and titrate; full 10 mg may behave like 20 mg in this population.
eGFR < 30 / dialysis
Atorvastatin 10-20 mg or pravastatin 40-80 mg
Atorva and prava don't need renal adjustment. Rosuvastatin: max 10 mg if eGFR < 30. Avoid statin in dialysis primary prevention (4D, AURORA showed no benefit); continue if already on it for ASCVD.
Pure cost-sensitive patient (no insurance, no comorbidities)
Simvastatin 20-40 mg at bedtime
Cheapest generic. Watch CYP3A4 interactions. Avoid 80 mg (FDA black-box for rhabdo). Atorva is now generic and similarly priced -prefer it when available.
Cannot tolerate atorva or rosuva at any dose
Pravastatin 40-80 mg
Hydrophilic statin with the lowest myalgia rate in head-to-head data. Less potent than atorva/rosuva (mid-moderate intensity at max), but a real option in true intolerance before declaring "non-statin only."
Pregnancy
STOP all statins
Teratogenic (FDA category X historically; 2021 FDA softened wording but pregnancy is still a contraindication for moderate or high doses). Bile acid sequestrants are the only acceptable lipid agent in pregnancy. Resume after delivery / breastfeeding.
2026 framework calls for moderate-intensity in: primary prevention with PREVENT 5-<10% (intermediate, LDL goal < 100), DM age 40-75 without high-risk features (LDL < 100), DM age 30-39 with LDL ≥ 160 or elevated 30-yr PREVENT, and borderline 3-<5% if SDM favors treatment. Don't drop to moderate-intensity from a high-intensity indication out of habit -if the patient has ASCVD or PREVENT ≥ 10%, the indication is high-intensity, even if you're choosing a low-CYP3A4 drug.
▶ Low-intensity statin: when (rarely) it's the right answer
Low-intensity statin is rarely a first choice in 2026. The "lower for longer" framing pushes toward at least moderate-intensity from day 1. Low-intensity (< 30% LDL ↓) is mostly a tolerability fallback, not a primary indication. Drugs: simvastatin 10 mg, pravastatin 10-20 mg, lovastatin 20 mg, fluvastatin 20-40 mg.
Scenario
Drug + dose
Why
True statin intolerance, working up the ladder
Rosuvastatin 5 mg every other day or atorvastatin 10 mg every 3 days
Alternative-day regimens count as "low-intensity" by total weekly exposure. Many "intolerant" patients tolerate these (n-of-1 rechallenge after SAMSON, 2020). Better than declaring "non-statin only."
Frail elderly with severe polypharmacy
Pravastatin 10-20 mg or simvastatin 10 mg
When the goal is "any statin exposure" rather than achieving an LDL target, and the patient won't tolerate higher doses. Individualize -frailty, life expectancy, falls risk, drug burden all weigh in.
Drug-interaction forced floor (e.g., HIV on PI plus other CYP3A4 inhibitors)
Pravastatin 10-20 mg or pitavastatin 1 mg
When even moderate-intensity at standard dose isn't safe due to overlapping inhibitors. Combine with ezetimibe to recover some LDL drop without raising statin dose.
Borderline 3-<5% PREVENT with patient hesitance
Lifestyle first; if statin chosen via SDM: pravastatin 10-20 mg
Some patients in the borderline band insist on a "lowest possible" exposure. Defensible compromise: low-intensity statin + lifestyle + reassessment in 6-12 mo. CAC scoring is more useful here than dose-titration.
Don't confuse "low-intensity" with "low dose of a high-intensity drug": rosuvastatin 5 mg DAILY = moderate-intensity (≥ 30% LDL ↓). Rosuvastatin 5 mg EVERY OTHER DAY ≈ low-intensity. Atorvastatin 10 mg DAILY = moderate-intensity. The distinction is total weekly exposure, not the drug name.
Avoid: Simvastatin 10 mg "to start, then titrate" in a young patient with a clear high-intensity indication -that's wasted treatment time. Either commit to moderate-intensity (atorva 20 / rosuva 10) or work up the intolerance ladder explicitly. Don't drift on subtherapeutic dosing.
Statin side effects: myalgia (~5-10%, often nocebo on rechallenge), rhabdomyolysis (rare, < 0.1%), liver enzyme elevation (rarely clinically significant), small absolute increase in DM diagnosis (~1 case per 1000 patient-years -CV benefit far outweighs), cognitive symptoms (controversial, not borne out in trials). Avoid in pregnancy (teratogenic).
▶ When to stop a statin: LFT, CK, and clinical thresholds
Framing first: the FDA dropped routine LFT monitoring in 2012, and routine CK was never recommended. Don't recheck unless the patient has symptoms. Serial screening generated false alarms without catching the cases that mattered. Use clinical judgment + symptoms, not isolated lab numbers.
LFT-driven decisions
ALT or AST level
Action
< 3× ULN, asymptomatic
Continue. Don't stop, don't even recheck unless symptoms develop. Most mild transaminitis on statin is unrelated (NAFLD/MASLD, alcohol, viral hepatitis).
3-5× ULN, asymptomatic
Repeat in 1-2 weeks. Transient → continue. Persistent → work up other causes (NAFLD, alcohol, viral, autoimmune) before blaming the statin.
> 3× ULN WITH symptoms (fatigue, jaundice, RUQ pain, dark urine)
Hold the statin. Evaluate for clinical hepatitis. Rechallenge later with a different statin (pravastatin or pitavastatin -lowest hepatic burden) if no other cause is identified.
Permanent discontinuation. Work up acute liver failure. Switch to non-statin LDL-lowering: ezetimibe, bempedoic acid, PCSK9i, or inclisiran.
Non-contraindications -don't withhold a statin for these:
NAFLD / MASLD -statins are safe and may IMPROVE liver outcomes (don't withhold)
Compensated cirrhosis (Child-Pugh A) -generally safe; benefit usually outweighs risk
Stable mild ALT elevation (e.g., chronic 1.5× ULN from fatty liver) -continue
Genuine contraindications:
Active acute hepatitis (viral, drug-induced, autoimmune) -hold until resolved
Decompensated cirrhosis (Child-Pugh B or C with ascites / encephalopathy / variceal bleeding) -relative contraindication
Acute liver failure -absolute contraindication
CK-driven decisions
CK level
Action
< 5× ULN, asymptomatic
Continue. Common with exercise, IM injection, sex/race normal variation.
< 5× ULN WITH myalgia
Trial off, confirm symptoms resolve, rechallenge. Most "intolerance" is nocebo (SAMSON, 2020 -90% rechallenge tolerance).
5-10× ULN with myalgia
Hold statin, monitor CK trend. Rule out hypothyroidism (#1 reversible mimic), vitamin D deficiency, drug interaction (CYP3A4 inhibitors). Rechallenge with low-dose alternative regimen (rosuva 5 mg every other day, atorva 10 mg every 3 days).
> 10× ULN OR myoglobinuria / AKI
Stop immediately. Treat as rhabdomyolysis -IV fluids, monitor for AKI, evaluate for trigger (drug interaction, exercise, viral). Permanent discontinuation of that statin. Switch to bempedoic acid (no muscle effects) or ezetimibe-based regimen ± PCSK9i.
Routine baseline and monitoring rules:
LFTs at baseline -yes (identifies pre-existing liver disease that affects regimen choice). Do NOT recheck routinely -only if symptoms (FDA 2012 update).
CK at baseline -only in selected patients: prior myopathy, multi-statin exposure, high-risk drug interactions, severe renal/hepatic disease. Routine CK is not recommended.
TSH -check at baseline AND if myalgia develops. Hypothyroidism is the #1 reversible cause of statin-mimicking myalgia and the #1 reversible cause of secondary hypercholesterolemia.
Non-Statin LDL-Lowering Agents
Drug
Dose
LDL Reduction
Key Use / Trial
Ezetimibe (Zetia) 2ND LINE
10 mg PO daily
~20-25%
First add-on after maxed statin. IMPROVE-IT, 2015 -reduced MACE post-ACS. Cheap, well-tolerated, no major interactions.
Evolocumab (Repatha) PCSK9i
140 mg SC q2 weeks OR 420 mg monthly
~50-60%
FOURIER, 2017. GLAGOV, 2016: plaque regression on IVUS. EBBINGHAUS, 2017: no cognitive harm. For ASCVD or FH not at goal on max statin + ezetimibe. Expensive (~$5,800/yr but coverage often available with prior auth).
Alirocumab (Praluent) PCSK9i
75 or 150 mg SC q2 weeks
~50-60%
ODYSSEY OUTCOMES, 2018. Same indications as evolocumab.
Inclisiran (Leqvio) siRNA
284 mg SC at 0, 3 months, then q6 months
~50%
ORION 9/10/11. Twice-yearly injection -excellent adherence advantage. Same indications as PCSK9 mAbs. CV outcome trial pending.
Combination pill, useful for statin-intolerant patients needing more LDL drop than either alone.
Cholestyramine, colestipol, colesevelam (Welchol) RARELY USED
Cholestyramine 4 g BID; colesevelam 3.75 g daily
~15-30%
Bile acid sequestrants. GI side effects (constipation), interfere with absorption of other drugs (separate by 4 h). Niche use. Colesevelam also lowers A1c modestly.
Triglyceride-Lowering Agents
Drug
Dose
Notes
Fenofibrate (Tricor, Trilipix) PREFERRED FIBRATE
145 mg PO daily (with food)
Reduces TG ~30-50%. Safe to combine with statins. Watch Cr (mild reversible rise common -don't reflexively discontinue), myopathy when combined with statin (low rate). Indication: TG ≥ 500.
Gemfibrozil (Lopid) AVOID WITH STATIN
600 mg PO BID
Inhibits statin glucuronidation -markedly increases rhabdomyolysis risk. Use only as monotherapy, not combined with statin. Otherwise effective for TG.
Icosapent ethyl (Vascepa) CV BENEFIT
2 g PO BID with meals
Pure EPA (not mixed omega-3). REDUCE-IT, 2019: 25% MACE reduction in patients with ASCVD or DM + TG 150-499 on statin. Mixed omega-3 (Lovaza, fish oil supplements) does NOT show this benefit -don't substitute.
Omega-3 (Lovaza, OTC fish oil) TG ONLY
4 g daily
Lowers TG ~20-30%. STRENGTH 2020 was negative for CV outcomes. Use only if pure EPA (Vascepa) not available; inferior choice.
Niacin (Niaspan) RARELY USED
500-2000 mg PO daily
AIM-HIGH 2011 and HPS2-THRIVE 2014 were negative for CV outcomes when added to statin. Side effects: flushing (worsened by alcohol/spicy food, reduced by ASA pretreatment), hyperglycemia, hyperuricemia/gout, hepatotoxicity. Largely abandoned.
⚠️ Refractory & Special Populations
Statin Intolerance
Most "statin intolerance" is nocebo or unrelated myalgia. SAMSON 2020 and similar n-of-1 trials show 90% of "statin-intolerant" patients tolerate the same statin on blinded rechallenge. Always rechallenge before labeling intolerant.
Confirm: stop statin, confirm symptoms resolve, restart same or different statin -if symptoms recur reproducibly, label intolerant.
Rule out alternatives: hypothyroidism (TSH), vitamin D deficiency, polymyalgia rheumatica, drug interaction (CYP3A4 inhibitors).
Switch statin: try a hydrophilic statin (pravastatin) or low-dose alternative (rosuvastatin 5 mg every other day, atorvastatin 10 mg q3 days). Many patients tolerate alternative regimens.
Add non-statin agents: ezetimibe + bempedoic acid + PCSK9i / inclisiran can replicate statin LDL-lowering without statin exposure.
Heterozygous FH: ~1 in 200-500. Untreated LDL typically 200-400, with premature CAD often by age 40 men / 50 women.
Homozygous FH: rare (~1 in 1 million), LDL often > 500, CAD in childhood, requires apheresis ± PCSK9i ± lomitapide / evinacumab.
Diagnosis: LDL ≥ 190 + family hx of premature CAD, or genetic confirmation. Dutch Lipid Clinic Network or Simon Broome criteria.
Treatment: high-intensity statin + ezetimibe early. PCSK9i / inclisiran often needed -insurance approval is reasonable for FH. Goal: LDL reduction ≥ 50%, < 100 (or < 70 if also ASCVD).
Cascade family screening: test all first-degree relatives. Children of an affected parent have 50% risk.
Lipoprotein(a): often elevated in FH; check once. PCSK9i and inclisiran modestly lower Lp(a); apheresis for very high Lp(a) refractory to drugs.
Lp(a) -Targeted Therapies (emerging, 2024-2025)
Lp(a) is a strong, genetically-determined ASCVD risk factor with no approved Lp(a)-specific therapy yet. PCSK9i and inclisiran lower Lp(a) ~20-25% as a side effect; apheresis is the only intervention with proven Lp(a) reduction > 50%. Several agents in late-stage trials are expected to change practice 2025-2027.
Selective Lp(a) and LDL removal via column, weekly or biweekly
~50-75% per session
FDA-approved for Lp(a) ≥ 60 mg/dL with progressive ASCVD despite max therapy. Burdensome (4-6 hour sessions q1-2 weeks). Reserved for refractory disease until drugs approved.
Key knowledge gap: all four investigational agents lower Lp(a) dramatically, but none has yet shown CV outcome benefit. The field assumes Lp(a) reduction reduces ASCVD events (Mendelian randomization supports this), but ongoing Phase 3 trials will define if and how much. Until then, focus on optimizing standard ASCVD risk factors aggressively in elevated-Lp(a) patients (lower LDL goal, BP control, statin + ezetimibe ± PCSK9i).
Special Populations
Population
Considerations
Pregnancy
STOP all statins, ezetimibe, fibrates, niacin, PCSK9i -teratogenic or insufficient data. Bile acid sequestrants safe. Resume after delivery / breastfeeding.
Elderly (> 75)
Continue statin if life expectancy > 1 year and tolerating. Initiate based on individualized risk-benefit. ASPREE 2018: aspirin in elderly without prior CV disease no benefit + harm. Statins still beneficial for secondary prevention.
HIV / on protease inhibitors
Avoid simvastatin and lovastatin (severe CYP3A4 interactions). Use pravastatin, pitavastatin, or rosuvastatin. PCSK9i safe. REPRIEVE, 2023: pitavastatin 4 mg reduced MACE 35% in HIV patients age 40-75 even at low-moderate ASCVD risk and LDL below standard treatment threshold -statin recommended for primary prevention in HIV regardless of LDL.
CKD (eGFR < 60)
CKD itself is a risk enhancer -lowers threshold for statin. Pravastatin or atorvastatin OK without renal adjustment. Rosuvastatin reduce dose at eGFR < 30 (max 10 mg). SHARP, 2011: simva + ezetimibe reduced MACE 17% in CKD pre-dialysis. Avoid statin if on dialysis without prior ASCVD (4D, AURORA negative).
Liver disease
Statins safe in NAFLD/MASLD (often help). Avoid in active hepatitis or decompensated cirrhosis. Mild ALT elevation alone is not a contraindication.
Transplant on calcineurin inhibitors
Cyclosporine increases statin levels. Use pravastatin or pitavastatin at low dose. Avoid simvastatin/lovastatin.
📋 On Rounds
Pimp Questions
What changed in the 2026 ACC/AHA Dyslipidemia Guideline?
Released March 13, 2026; replaces the 2018 Cholesterol Guideline. Six big changes: (1) PREVENT-ASCVD calculator replaces 2013 PCE -no race input, includes CKD, ages 30-79. (2) New risk categories: low <3%, borderline 3-<5%, intermediate 5-<10%, high ≥10%. (3) Lower numeric LDL goals in primary prevention: <70 if PREVENT ≥10%, <100 if 5-<10%. (4) Earlier statin starts: all HeFH at diagnosis, age ≤30 with LDL ≥160, strong family hx, high 30-yr PREVENT. (5) Routine apoB and Lp(a) testing. (6) Non-statin add-ons reframed as parallel options (ezetimibe / bempedoic acid / PCSK9i / inclisiran) -not a strict ladder. Core principle: "lower LDL for longer is better" -cumulative-exposure framing.
What are the 2026 statin indications?
(1) Clinical ASCVD -high-intensity statin; LDL < 55 if very-high-risk, < 70 otherwise. (2) LDL ≥ 190 -high-intensity regardless of risk; treat HeFH at diagnosis. (3) Primary prevention by PREVENT: ≥10% high-intensity, <70 goal; 5-<10% moderate-intensity, <100 goal; 3-<5% SDM. (4) Diabetes -moderate-intensity baseline, high-intensity if PREVENT ≥10% or ASCVD. (5) NEW: early intervention -age ≤30 with LDL ≥160, strong family hx, high 30-yr PREVENT. Rationale: cumulative LDL exposure ("LDL pack-years") drives lifetime risk.
Why did 2026 introduce numeric LDL goals in primary prevention when 2018 didn't have them?
2018 used "≥50% reduction" as the only target -no absolute number for primary prevention. 2026 added <70 for high-risk and <100 for intermediate-risk primary prevention based on accumulated CTT meta-analytic evidence and FOURIER / ODYSSEY OUTCOMES safety data showing benefit continues to LDL ~20-30 with no floor. Combined with PREVENT producing lower 10-yr risk estimates, lower numeric goals keep treatment intensity calibrated to actual risk. The framing is "lower for longer is better" -cumulative LDL exposure drives lifetime ASCVD, so push targets lower in primary prevention.
A 55F with LDL 220, no symptoms, family history of MI in father at 48. What's the diagnosis and management?
Familial hypercholesterolemia (heterozygous) until proven otherwise. LDL ≥ 190 + premature CAD in first-degree relative meets clinical criteria. Workup: rule out secondary causes (TSH, UACR, LFTs), genetic testing (LDLR most common), exam for xanthomas / xanthelasma. Management: high-intensity statin (atorvastatin 40-80 or rosuvastatin 20-40) + ezetimibe early; add PCSK9i / inclisiran if LDL not at goal. Goal ≥ 50% LDL reduction, < 100 (or < 70 if also ASCVD). Cascade family screening -test all first-degree relatives (50% affected).
When do you check Lp(a)?
Once per lifetime in adults (it's genetically determined and doesn't change). Especially in: family history of premature ASCVD, FH, recurrent ASCVD events despite optimal statin, or borderline ASCVD risk needing tiebreaker. Lp(a) ≥ 50 mg/dL (or ≥ 125 nmol/L) is a major risk enhancer -pushes borderline patients toward statin and intensifies treatment in established disease. Statins do NOT lower Lp(a) (sometimes raise it). PCSK9i and inclisiran modestly lower it (~25%). Apheresis for very high refractory levels.
Why avoid gemfibrozil with a statin?
Gemfibrozil inhibits glucuronidation of statins, increasing statin plasma levels and the risk of severe rhabdomyolysis. Cerivastatin (withdrawn) caused multiple fatal rhabdo cases when combined with gemfibrozil. Use fenofibrate instead when combining with a statin -it doesn't have the same interaction. If gemfibrozil is necessary, use as monotherapy.
A patient with ASCVD on atorvastatin 80 and ezetimibe 10 still has LDL 95. Goal < 70. Next step?
Add a PCSK9 inhibitor -evolocumab 140 mg SC q2 weeks or alirocumab 75-150 mg SC q2 weeks. Will reduce LDL another 50-60%, easily getting below 70 (often below 30). Alternative: inclisiran 284 mg SC at 0, 3 months, then q6 months for adherence advantage. Both are FDA-approved for ASCVD or FH not at goal on max-tolerated statin + ezetimibe. Insurance often covers with prior authorization. Bempedoic acid is an oral alternative if injection is unacceptable, but smaller LDL effect.
Clinical Examples
📋 Case 1, Primary prevention with intermediate risk
Patient: 52F, BP 128/82, LDL 145, HDL 48, TG 150, A1c 5.7%, no DM, no ASCVD, non-smoker, mother had MI at 58. PREVENT 10-yr risk = 6.8%.
Key findings: 2026 intermediate-risk band (PREVENT 5 to <10%). Risk enhancer present (premature ASCVD in mother < 65). LDL above 130 also an enhancer.
Management:
Start moderate-intensity statin per 2026 guideline (intermediate-risk band): atorvastatin 20 mg or rosuvastatin 10 mg.
LDL goal < 100 mg/dL (2026 added a numeric goal for the intermediate band; 2018 had none for primary prevention).
Risk enhancers (mother MI < 65, LDL ≥ 130) reinforce the indication; CAC score is optional now -more useful as a tiebreaker in the borderline 3-<5% band, less needed at PREVENT 6.8%.
Lifestyle: Mediterranean diet, exercise 150 min/week, smoking cessation if applicable.
Recheck lipid panel in 4-12 weeks; intensify to high-intensity or add ezetimibe if not at < 100 (or push lower given her risk enhancers).
Teaching point: The 2026 framework relabels 5-7.5% (an old PCE borderline tier) as intermediate risk (PREVENT 5-<10%), with a numeric LDL goal of < 100. CAC scoring is most useful in the new borderline 3-<5% band, where SDM dominates -CAC = 0 reasonably defers statin; CAC > 100 supports starting.
📋 Case 2, Very-high-risk secondary prevention not at goal
Patient: 65M with prior MI 2 years ago, hypertension on lisinopril. On atorvastatin 80 mg, aspirin 81 mg, metoprolol. LDL 92, HDL 42, TG 180, apoB 78.
Key findings:Very-high-risk ASCVD per 2026 (one major event + multiple high-risk conditions: age ≥ 65 AND HTN). LDL goal is therefore < 55 mg/dL (apoB < 55), not < 70. He's far from goal at LDL 92 despite max-intensity statin -needs combination therapy.
Management:
Continue atorvastatin 80 mg (already at maximum-intensity).
Add ezetimibe 10 mg daily -expected ~20% further LDL drop → ~LDL 73 (IMPROVE-IT, 2015). Still won't hit < 55.
Add PCSK9i (evolocumab 140 mg SC q2 wk or alirocumab 75-150 mg SC q2 wk) -another ~50-60% drop → LDL ~30, comfortably below 55. Alternative: inclisiran 284 mg SC at 0, 3 months, then q6 mo for adherence advantage. FOURIER, 2017 · ODYSSEY OUTCOMES, 2018.
Consider adding icosapent ethyl 2 g BID for residual TG-driven ASCVD risk at TG 180 (REDUCE-IT, 2019).
Reinforce lifestyle, adherence, and aspirin.
Teaching point: The 2026 guideline split ASCVD into very-high-risk (LDL < 55, apoB < 55) and standard-risk (< 70). One MI + age ≥ 65 + HTN = very-high-risk → triple therapy (statin + ezetimibe + PCSK9i / inclisiran) is often the rule, not the exception. Ezetimibe alone won't get this patient to goal -don't stop there.
Key findings: Severe hypertriglyceridemia with pancreatitis. Multiple secondary causes (uncontrolled DM, alcohol).
Management:
Acute: NPO, IV fluids, treat pancreatitis. Insulin drip ± heparin for severe hypertriglyceridemia. Apheresis if persistent > 1000 with worsening pancreatitis.
Add icosapent ethyl 2 g BID -25% MACE reduction in DM/ASCVD with persistent TG 150-499 on statin (REDUCE-IT 2019). Distinct from generic OTC fish oil (mixed EPA/DHA, no CV benefit).
Once TG < 500 and stable: start moderate-intensity statin (atorvastatin 20 mg or rosuvastatin 10 mg) -DM is an automatic 2026 statin indication. LDL goal < 100 (or < 70 if PREVENT ≥ 10% or other ASCVD risk emerges). Recheck PREVENT once DM is controlled; uncontrolled A1c inflates the score.
Teaching point: TG ≥ 1000 = pancreatitis emergency. Treat secondary causes aggressively (DM, alcohol). Fibrate first-line for prevention -statin doesn't address pancreatitis risk (that's a fibrate / EPA / dietary fat target). But once TG settles, the patient still needs a statin: DM is one of the 5 standalone 2026 statin indications, regardless of his LDL number.
⚡ Summary
Summary
2026 Framework
PREVENT-ASCVD replaces the pooled cohort equations: low <3%, borderline 3-<5%, intermediate 5-<10%, high ≥10%. Race dropped, 30-year risk added. Core idea is lower for longer, since cumulative LDL exposure drives plaque.
2026 LDL Goals
Very-high-risk ASCVD <55 (apoB <55). Standard ASCVD <70. Primary prevention <70 if high risk, <100 if intermediate. Numeric primary-prevention goals are new in 2026 and are what trigger add-on therapy.
Who Gets a Statin
ASCVD, LDL ≥190, diabetes, PREVENT ≥10% (high-intensity) or 5-<10% (moderate). NEW: early intervention at age ≤30 with LDL ≥160, HeFH, or high 30-year risk, because 10-year risk is always low in the young. In HIV, treat regardless of LDL (REPRIEVE).
Intensity
High = atorvastatin 40-80 or rosuvastatin 20-40 (≥50% LDL reduction). Moderate = atorvastatin 10-20 or rosuvastatin 5-10 (30-49%). Defined by percent reduction, not by milligrams.
Lp(a) and apoB
Lp(a) once per lifetime, genetically fixed so one measurement settles it. apoB when LDL is at goal, TG ≥150, or in diabetes, where LDL-C understates particle number and hides residual risk.
Add-Ons Are Parallel
Ezetimibe, bempedoic acid, PCSK9i mAb and inclisiran are parallel options, not a fixed ladder, so choose on cost and route. Combination is expected in very-high-risk patients, where a statin alone rarely reaches LDL <55.
Familial Hypercholesterolemia
LDL ≥190 is FH until proven otherwise. High-intensity statin + ezetimibe + PCSK9i, started at diagnosis rather than after a risk score. Cascade screen relatives: each first-degree relative has a 50% chance.
High Triglycerides
≥500: fenofibrate, never gemfibrozil with a statin (rhabdomyolysis). ≥1000: pancreatitis risk, which is why you treat urgently. ASCVD with TG 150-499: icosapent ethyl (REDUCE-IT). PROMINENT ended fibrates for ASCVD benefit.
Statin Intolerance
Mostly nocebo: SAMSON found the same symptoms on placebo. Rechallenge with a different agent or alternate-day dosing before labeling anyone intolerant, since the label costs decades of protection. Then bempedoic acid, ezetimibe, PCSK9i.
Pregnancy
Stop statins, ezetimibe, fibrates, niacin and PCSK9 inhibitors. Bile acid sequestrants only, since they are not absorbed. Discuss contraception before starting a statin and plan the interruption in advance.
RoundsRx Infographic Series · #154 · Cardiovascular · PDF 157 KB
Text version
AMBULATORY · One Pager
Outpatient Lipid Management
Find the indication first, start at the intensity that indication demands rather than titrating up, then verify the percentage drop, because lower LDL for longer is what buys the risk reduction.
🧪 Who Gets a Statin (5 Indications)
1. Clinical ASCVD (prior MI, stable angina, coronary revascularization, stroke/TIA, PAD with imaging): high-intensity statin, plus ASA 81 mg daily. Eligibility is the diagnosis, so no risk score is needed.
2. Severe hypercholesterolemia, LDL ≥190 (often FH): high-intensity regardless of risk, goal ≥50% LDL reduction. Treat HeFH at diagnosis; children with HeFH from age 8–10.
3. Primary prevention by PREVENT (age 30–79, LDL 70–189, no DM, no prior event): ≥10% high-intensity with LDL goal <70; 5 to <10% moderate-intensity with goal <100; 3 to <5% shared decision-making with risk enhancers or CAC.
4. Diabetes age 40–75 with LDL 70–189: moderate-intensity baseline, high-intensity if PREVENT ≥10%, multiple risk enhancers, or established ASCVD. Consider age 30–39 if LDL ≥160 or elevated 30-year PREVENT.
5. Early intervention (NEW 2026): HeFH at any age, age ≤30 with LDL ≥160, strong family history of premature ASCVD, or high 30-year PREVENT. Cumulative LDL exposure drives lifetime risk, so delaying wastes the longest-yield window.
⚡ LDL Targets and Risk Bands
Very-high-risk ASCVD: LDL <55, apoB <55, plus ≥50% reduction from baseline. Qualifies by any of: recurrent events, polyvascular disease (≥2 of CAD, cerebrovascular, PAD), one event plus multiple high-risk conditions (age ≥65, HeFH, DM, CKD eGFR 15–59, HTN, smoking, prior CABG/PCI, persistent LDL ≥100 on max therapy, HF), or Lp(a) ≥50 with ASCVD.
Standard-risk ASCVD: LDL <70, apoB <70.
PREVENT ≥10% (high): LDL <70.5 to <10% (intermediate): <100.3 to <5% (borderline): optional, <100 if treated, CAC is the useful tiebreaker here. <3% (low): lifestyle, reassess in 4–6 years.
Diabetes: <70 if ASCVD or multiple risk factors, <100 otherwise.
Heterozygous FH: <100, or <70 if also ASCVD, with ≥50% reduction. Homozygous FH: <100, treatment-intensive.
Do not use PREVENT after an ASCVD event; it is not validated post-event, so classify by clinical features instead. The percentage rule never produces a <55 goal.
🚨 Management, Step by Step
1
Identify the indication before calculating anything: clinical ASCVD, LDL ≥190, diabetes, primary prevention by PREVENT, or the 2026 early-intervention category. If none apply, lifestyle and reassess in 4–6 years.
2
Baseline labs that change management: lipid panel, TSH (hypothyroidism is the leading reversible cause of high LDL, and treating it often normalizes the LDL on its own), BMP/eGFR, HbA1c, LFTs, plus Lp(a) once per lifetime and apoB if TG ≥150, DM, or LDL is low on therapy. CK only if myalgia or myopathy risk factors.
3
Start at the indicated intensity, do not titrate up. High-intensity is atorvastatin 40–80 or rosuvastatin 20–40 (≥50% drop); moderate is atorvastatin 10–20 or rosuvastatin 5–10 (30–49%). Each year at a suboptimal LDL is a year of lost benefit.
4
Recheck at 4–12 weeks, sweet spot 6–8. Statins reach steady-state nadir at ~4 weeks, so checking earlier risks falsely calling a non-response. Verify the percentage drop, which is a better adherence signal than the absolute LDL. If the drop is short, check adherence first, because about half of patients stop within a year.
5
Not at goal? Add a non-statin in parallel, not as a slow ladder: ezetimibe (cheap, oral, usual first add-on), bempedoic acid (oral, statin-intolerant), PCSK9i mAb (largest LDL drop), or inclisiran (twice-yearly, adherence). For very-high-risk patients far from goal, starting statin plus ezetimibe together on day 1 is explicitly supported.
6
Run the triglyceride pathway in parallel, not after LDL. TG 150–499 with ASCVD or DM plus risk on statin gets icosapent ethyl 2 g BID; TG 500–999 gets fenofibrate for pancreatitis prevention; TG ≥1000 is urgent.
💊 Key Drugs
Atorvastatin (Lipitor)10–80 mg daily, any time of day; CYP3A4, watch macrolides, azoles, amiodarone, diltiazem, verapamil, grapefruit. No renal adjustment
Rosuvastatin (Crestor)5–40 mg daily; most potent per mg, minimal CYP3A4. Max 10 mg if eGFR <30; start 5 mg in Asian patients
Pravastatin (Pravachol)10–80 mg daily; hydrophilic, safest interaction profile, useful in HIV on PI and transplant on cyclosporine. Less potent
Ezetimibe (Zetia)10 mg daily, ~20–25% additional LDL drop; default first add-on, cheap with outcome data
Evolocumab (Repatha)140 mg SC q2 weeks or 420 mg monthly, ~50–60% additional; for ASCVD or FH not at goal on max statin plus ezetimibe
Alirocumab (Praluent)75 or 150 mg SC q2 weeks, ~50–60% additional; same indications as evolocumab
Inclisiran (Leqvio)284 mg SC at 0 and 3 months then q6 months, ~50%; twice-yearly dosing is the adherence advantage
Bempedoic acid (Nexletol)180 mg daily, ~17–25%; activated in liver not muscle, so no myalgia. Watch uric acid and gout
Icosapent ethyl (Vascepa)2 g PO BID with meals; pure EPA, do not substitute mixed omega-3
Fenofibrate (Tricor)145 mg daily with food, TG down ~30–50%; the fibrate to use with a statin. Indication is TG ≥500
📊 Monitoring
Lipid panel 4–12 weeks after starting or changing therapy (6–8 is the sweet spot), which is when the ≥50% reduction goal is actually measured.
Annual lipid panel once stable at goal, mainly to catch adherence drift.
Do not recheck LFTs routinely (the FDA dropped routine monitoring in 2012); check only for symptoms or a specific concern.
Do not check CK routinely; baseline only in selected patients (prior myopathy, multi-statin exposure, high-risk interactions, severe renal or hepatic disease), and on new myalgia.
TSH at baseline and again if myalgia develops, since hypothyroidism is the leading reversible mimic of statin myalgia and the leading reversible cause of secondary hypercholesterolemia.
Recheck adherence before escalating. About 50% of patients discontinue statins within one year, often without saying so.
Watch creatinine on fenofibrate: a mild reversible rise is common and is not by itself a reason to stop.
⚠️ Pitfalls
Starting low and creeping up when the indication is high-intensity. That is treatment time lost at a suboptimal LDL.
Gemfibrozil with a statin. It inhibits statin glucuronidation and markedly raises rhabdomyolysis risk. Use fenofibrate when combining.
Declaring statin intolerance on the first complaint. Rechallenge first, and rule out hypothyroidism, vitamin D deficiency, and CYP3A4 interactions.
Stopping the statin for statin-associated new-onset diabetes. Continue it and treat the diabetes; CV benefit far outweighs roughly 1 case per 1000 patient-years.
Withholding a statin for NAFLD/MASLD, compensated cirrhosis, or a stable mild ALT elevation. None of these are contraindications; active hepatitis, decompensated cirrhosis, and acute liver failure are.
Simvastatin 80 mg (FDA black box for rhabdomyolysis), and simvastatin or lovastatin with protease inhibitors or cyclosporine.
Substituting OTC fish oil or Lovaza for icosapent ethyl. The CV outcome data belongs to pure EPA only.
Forgetting to stop lipid therapy in pregnancy. Statins, ezetimibe, fibrates, niacin, and PCSK9i all stop; bile acid sequestrants are the only option.
🏥 Escalate, Refer, or Modify the Drug When
LDL ≥190: presume FH until proven otherwise (HeFH is ~1 in 200–500). Rule out secondary causes (TSH, UACR, LFTs), examine for tendinous xanthomas, xanthelasma, and corneal arcus <45, consider genetic testing, and cascade-screen first-degree relatives, half of whom will be affected.
Homozygous FH (LDL often >500): specialty lipid clinic for statin plus ezetimibe plus PCSK9i plus apheresis, with lomitapide or evinacumab, because standard therapy cannot reach goal.
TG ≥1000: imminent pancreatitis risk. Fibrate plus icosapent ethyl, dietary fat <15% of calories, eliminate alcohol, treat secondary causes (uncontrolled DM, alcohol, obesity, hypothyroidism, nephrotic syndrome, offending drugs), and genetic workup if persistent.
True statin intolerance (reproducible myopathy on 2 or more statins, not nocebo): bempedoic acid with or without ezetimibe and PCSK9i. Try an alternative low-dose regimen such as rosuvastatin 5 mg every other day first.
CK >10× ULN or myoglobinuria/AKI: stop immediately, treat as rhabdomyolysis, permanently discontinue that statin.
ALT/AST >10× ULN or clinical hepatitis: permanent discontinuation and non-statin LDL lowering instead.
Elevated Lp(a) ≥50 mg/dL: intensify LDL lowering and counsel family screening. No Lp(a)-specific drug is approved yet, and PCSK9i lowers it only ~25%.
Modify the drug, not the intensity tier, for special populations: Asian patients start rosuvastatin 5 mg; eGFR <30 use rosuvastatin max 10 mg or pravastatin/atorvastatin; HIV on a protease inhibitor use pravastatin, pitavastatin, or rosuvastatin; cyclosporine use pravastatin or pitavastatin; pregnancy stop all statins.
🎓 Key Evidence
CTT meta-analysis: each ~39 mg/dL LDL drop is about a 22% MACE reduction per year, compounding over time. This is why waiting six weeks at every step is costly.
IMPROVE-IT, 2015: ezetimibe added to statin post-ACS reduced MACE, making it the first add-on with outcome data.
FOURIER, 2017 and ODYSSEY OUTCOMES, 2018: ~15% MACE reduction each, and safety confirmed down to LDL ~20–30, which is what justifies pushing targets lower.
REDUCE-IT, 2019: 25% MACE reduction with icosapent ethyl on top of a statin.
PROMINENT, 2022 plus ACCORD-Lipid, 2010: fibrate-class CV benefit beyond statin is largely disproven, so fenofibrate is for pancreatitis prevention at TG ≥500, not risk reduction.
CLEAR Outcomes, 2023: 13% MACE reduction in statin-intolerant patients.
SAMSON, 2020: about 90% of statin-attributed symptoms are nocebo, which is why blinded rechallenge comes before the intolerance label.
SHARP, 2011: benefit in pre-dialysis CKD, while 4D and AURORA were negative, so do not start a statin for primary prevention in a dialysis patient.
REPRIEVE, 2023: pitavastatin 4 mg cut MACE 35% in HIV adults age 40–75 below the traditional LDL threshold.
Continuous seizure activity > 5 minutes or ≥ 2 seizures without return to baseline. A neurological emergency -every minute of seizure activity causes irreversible neuronal death. Stop it now.
🔍 Overview
Definitions
Status epilepticus (SE): Seizure ≥ 5 minutes OR ≥ 2 seizures without return to baseline between them.
Refractory SE: Failure of 2 first-line agents (benzodiazepine + second AED) -requires ICU admission and anesthetic agents.
Super-refractory SE: SE persisting ≥ 24 hours after initiation of anesthetic agents, including recurrence on weaning.
Causes
Known epilepsy + subtherapeutic AED levels (most common)
Autoimmune encephalitis (anti-NMDA receptor -especially young women)
Non-Convulsive SE (NCSE)
Don't miss this. NCSE presents as altered mental status, confusion, or subtle motor movements without obvious convulsions. Common after convulsive SE is "treated." Only diagnosed by EEG. Any patient with AMS after a seizure who doesn't wake up → get EEG.
🧪 Workup
Workup, While Treating
Workup happens in parallel with treatment. Never delay benzodiazepine administration to chase labs or imaging.
Fingerstick glucose FIRST, hypoglycemia is a reversible cause of seizure
BMP, Na (hyponatremia), Ca, Mg, renal function
AED levels (if patient on chronic anticonvulsants), subtherapeutic levels are a top cause of breakthrough SE
CBC, leukocytosis (infection, stress)
LFTs, ammonia, hepatic encephalopathy with myoclonus
Lactate, elevated early post-seizure (anaerobic metabolism); should clear within ~1h if seizure has stopped
Non-contrast CT head, rule out stroke, hemorrhage, mass, edema
LP, if meningitis/encephalitis suspected (fever, immunocompromised, signs of infection)
MRI brain, after acute stabilization; more sensitive for cortical lesions, autoimmune encephalitis
Continuous EEG × 24–48h, mandatory if patient doesn't rapidly return to baseline; diagnoses NCSE (present in up to 30% of persistent coma after convulsive SE)
Pregnancy test, eclampsia is a stroke mimic and changes AED choice (levetiracetam preferred; avoid valproate)
Autoimmune encephalitis panel (anti-NMDA-R, LGI1, GABA-B, etc.), if no clear etiology, especially young women
Post-Ictal LFT Gotcha, AST Is Muscle, Not Liver
Generalized tonic-clonic seizures cause subclinical-to-overt rhabdomyolysis. AST is constitutively present in skeletal muscle and leaks out when fibers lyse during the seizure (it isn't "produced" on demand, just released). ALT is in muscle too but at lower concentration, which is why the post-ictal pattern is AST > ALT, the opposite of viral hepatitis.
Classic post-ictal lab pattern:
↑↑ CK (often 1,000 to >10,000 U/L), confirms muscle source. Always order CK on a post-ictal LFT abnormality.
↑ AST and ↑ ALT, with AST > ALT. AST often 200–500 in moderate post-ictal rhabdo.
↑ LDH, ↑ aldolase (also leaked from muscle)
↑ K⁺, ↑ phosphate, ↓ Ca²⁺ (intracellular contents released; Ca²⁺ binds to damaged muscle and phosphate)
Tea-colored urine, dipstick + for blood with no RBCs on micro = myoglobinuria
AKI from myoglobin cast nephropathy (CK > 10,000 = high risk)
Why it matters: A post-ictal patient with AST 300 / ALT 200 / AST > ALT does not need a hepatitis serology workup. Check CK first. If CK is high, the LFT bump is muscle and trends down with hydration over 3–5 days. Chasing hepatitis B/C, ANA, and ferritin wastes time and money and delays the right intervention, IV fluids targeting UOP 200–300 mL/hr, q4–6h K⁺, watching for compartment syndrome.
One more nuance, myoglobin does NOT cause jaundice. Although myoglobin contains heme, its clinical fate in rhabdo is renal excretion (causing the tea-colored urine and pigment AKI), not conversion to bilirubin. Bilirubin overwhelmingly comes from hemoglobin breakdown by splenic macrophages (~80% of daily production). If a post-ictal or rhabdo patient is jaundiced, look elsewhere, hemolysis, ischemic hepatitis from shock, or drug-induced hepatic injury.
Post-Ictal Lab Timing Reference
Sorted from fastest-decay to slowest, so you know what's still recoverable as a diagnostic clue depending on when the patient hits your ED. Magnitudes are typical for a single GTC seizure; massive seizures or status epilepticus push everything higher.
Lab
Starts to Rise
Peaks
Back to Normal
Typical Magnitude
Why It Matters
Lactate
Within minutes
Immediate post-event
30–90 min
5–15 mmol/L
Best fast discriminator. Rapid clearance distinguishes post-ictal from sepsis (sepsis lactate doesn't drop in an hour). Cutoff: lactate > 2.5 mmol/L within 2h of TLOC has ~80% sensitivity, ~95% specificity for GTC seizure.
Anion gap / pH ↓
Minutes
Immediate
30–90 min
AG often > 16, pH 7.20–7.30
Tracks lactate. Resolves as lactate clears. Don't confuse with DKA or toxic ingestion if it's already correcting.
Prolactin
10–20 min
20 min
60 min
2–3× baseline
GTC vs PNES (psychogenic non-epileptic seizure). Useless if drawn after 60 min or in NCSE/focal/established status. Window matters.
WBC
Minutes (demargination)
1–2 hours
24–48h
12–20K, neutrophil-predominant
Mild leukocytosis is expected post-seizure, not necessarily infection. Don't reflex broad-spectrum antibiotics on WBC alone.
Cortisol
Minutes
30–60 min
2–4h
2–3× baseline
Not used for diagnosis. Explains the leukocytosis (demargination + neutrophilia + lymphopenia).
Glucose
Minutes
30–60 min
1–2h
150–250 mg/dL
Stress hyperglycemia from catecholamine surge. Don't restart insulin sliding scale based on a single post-ictal glucose.
Ammonia
Immediate
< 60 min
2–12h
2–3× ULN
Can falsely flag hepatic encephalopathy in a non-cirrhotic patient. Recheck in 4–6h before treating with lactulose.
Serum myoglobin
1–3h
6–12h
24h
Variable
Clears rapidly via kidney. Urine myoglobin lingers longer (24–48h). Rarely needed if CK is being trended.
Troponin
3–6h
6–12h
24–72h
Usually low-level (< 0.5 ng/mL)
False bump from sympathetic surge / demand ischemia. Don't reflex an ACS workup if seizure history is solid; trend it instead.
AST
6–12h
24–48h
3–5 days
200–500 U/L
Released from lysed muscle, not made by injured liver. AST > ALT (opposite of viral hepatitis).
ALT
6–12h
24–72h
3–7 days
100–300 U/L
Smaller bump than AST because muscle has less ALT. Tracks AST.
CK
2–12h
24–72h
5–7 days
1,000 to > 10,000 U/L
Best late marker. Confirms a convulsive event happened even days after the lactate window has closed. CK > 10,000 = high AKI risk.
Aldolase
6–12h
24–72h
5–7 days
Variable
Tracks CK. Rarely added if CK is already being trended; useful if CK is borderline and you want corroboration.
K⁺ ↑
Hours
12–24h
2–3 days
Up to 6–7 mEq/L in significant rhabdo
Arrhythmia risk window. Recheck q4–6h until trending down. Don't extrapolate from a single normal K⁺ at hour 2.
Phosphate ↑
Hours
12–24h
3–5 days
5–8 mg/dL
From muscle cell lysis. Contributes to hypocalcemia by binding free Ca²⁺.
Calcium ↓
Hours
24–48h (lowest)
1–2 weeks
Often 7–8 mg/dL corrected
Binds to damaged muscle and phosphate. Don't reflexively replace unless symptomatic, rebound hypercalcemia during recovery is common and replacement makes it worse.
Pigment cast nephropathy from myoglobin. Severity proportional to peak CK and time to fluids.
LDH
6–12h
24–48h
7–10 days
500–2,000 U/L
Long half-life; persists longest of all post-ictal markers. Useful retrospective clue if a patient presents days later with unclear history.
Key takeaways for clinical use:
Patient arrives within 1 hour of event: draw lactate, prolactin, ABG/VBG with anion gap. The fast-decay markers are still recoverable. After this window they're gone.
Patient arrives 2–6 hours later: lactate window may be missed. Pivot to early CK trend, troponin (with caveats), early AST/ALT, ammonia.
Patient arrives 24–72 hours later: CK is the workhorse. AST > ALT pattern still visible. LDH still elevated. Lactate and prolactin gone.
Patient arrives 3–7 days later: CK still mildly up, LDH still elevated, urine has cleared. Diagnostic certainty drops; lean on history, EEG, MRI.
Why Bilirubin Isn't on the Post-Ictal List
Despite myoglobin containing heme, post-ictal bilirubin is almost always normal. The myoglobin → heme oxygenase → biliverdin → bilirubin pathway is biochemically real but clinically negligible because myoglobin is renally excreted before metabolism. Bilirubin overwhelmingly comes from hemoglobin breakdown by splenic macrophages (~80% of daily production), and seizures don't cause hemolysis.
If a post-ictal patient IS jaundiced, look elsewhere:
Status epilepticus + shock → ischemic hepatitis ("shock liver"):direct or mixed ↑, AST in the thousands, LDH ↑↑↑, ↑ INR. Peaks 24–72h, falls fast once perfusion is restored.
AED-induced liver injury (DILI): direct ↑ with AST/ALT, often weeks after starting the drug. Valproate, lamotrigine, phenytoin are the usual suspects.
DRESS (drug-induced hypersensitivity): direct ↑ + eosinophilia + rash + fever. Carbamazepine, phenytoin, lamotrigine, days-to-weeks after initiation.
Underlying alcohol use or cirrhosis: bilirubin reflects baseline liver disease, not the seizure. Common in withdrawal-related seizures.
Hemolysis (any cause): haptoglobin ↓, retic ↑, schistocytes or spherocytes on smear.
Practical workup if post-ictal patient is jaundiced: CBC + smear + retic + haptoglobin (hemolysis), AST/ALT/INR/LDH trajectory (ischemic hepatitis), AED levels + medication review (DILI/DRESS), RUQ ultrasound if direct + alk phos predominant (obstruction).
Did a Seizure Actually Happen? Discriminator Table
When the event isn't witnessed or the story is fuzzy (post-ictal patient can't tell you what happened), these markers separate GTC seizure from syncope from PNES.
Feature
GTC Seizure
Syncope
PNES (psychogenic)
Lactate (early, < 1h)
↑↑ (often > 5 mmol/L) then rapid clearance
Normal or trivial bump
Normal
CK at 24h
Often > 1,000 U/L
Normal
Normal (rare exceptions in prolonged events)
Prolactin (drawn 10–60 min post)
2–3× baseline
Mild ↑ at most
Normal
Lateral tongue bite
~99% specific when present (sensitivity ~24%)
No
No
Postictal confusion
> 5 min, gradual recovery
< 30 sec, rapid full recovery
Variable, often abrupt return to baseline
Eyes during event
Open, often deviated
Open or closed
Often forcibly closed (resists examiner opening them)
Cyanosis
Common during tonic phase
Pallor more typical
Absent
Incontinence
Common (urinary > fecal)
Possible if prolonged
Possible (less specific than once thought)
🚨 Management
Status Epilepticus Protocol -Time Is Neurons
0–5 Minutes -Stabilize
ABCs, O₂, IV access, cardiac monitor. POC glucose STAT. If hypoglycemic → D50W (50% dextrose) 50 mL IV (= 25 g dextrose). Give thiamine 100 mg IV before or with dextrose if alcohol use, malnutrition, or unknown history (Wernicke prevention; alcohol withdrawal is a common SE precipitant). Check temperature (fever → active cooling, hyperthermia worsens neuronal injury). Place patient safely, do NOT restrain or put anything in mouth.
5 Minutes -Phase 1: Benzodiazepine (First-Line)
IV access available:Lorazepam (Ativan) 0.1 mg/kg IV (max 4 mg per dose), repeat × 1 in 5 min if no response (max total 8 mg). Alternative:Diazepam (Valium) 0.15–0.2 mg/kg IV (max 10 mg per dose), repeat × 1. No IV access:Midazolam (Versed)10 mg IM if ≥ 40 kg (5 mg IM if 13–40 kg). IM is as fast as IV, do not delay for IV access.
RAMPART 2012: IM midazolam = IV lorazepam in efficacy. Use IM if no IV. Why benzos first: they enhance GABAergic inhibition, the same neurotransmission that fails as SE persists (GABA-A receptors internalize, NMDA receptors externalize after ~30 min, which is why benzos lose potency in prolonged SE and you need NMDA antagonists like ketamine).
20 Minutes -Phase 2: Second AED (if benzo fails)
Give ONE of:
Levetiracetam (Keppra)60 mg/kg IV (max 4500 mg) over 10 min, preferred (fewest drug interactions, no respiratory depression, no cardiac monitoring needed)
Valproate (Depakote)40 mg/kg IV (max 3000 mg) over 10 min. Avoid in pregnancy (teratogenic, FDA black box), severe liver disease, mitochondrial disease (POLG mutations).
Fosphenytoin (Cerebyx)20 mg PE/kg IV (max 1500 mg PE), infusion rate ≤ 150 mg PE/min. Cardiac monitoring required (hypotension, arrhythmia during infusion). Use caution in severe liver disease (monitor free phenytoin levels), but not absolutely contraindicated in emergent SE. (Why fosphenytoin, not phenytoin: 3× faster infusion (150 vs 50 mg/min), no purple-glove tissue necrosis on extravasation, less propylene-glycol cardiotoxicity, IM option if IV is lost. Same active drug after 8–15 min plasma hydrolysis.)
Lacosamide (Vimpat)200–400 mg IV load over 5–15 min, then 100–200 mg IV/PO BID. ALTERNATIVE Not studied in ESETT, but increasingly used when LEV/VPA/PHT are contraindicated or fail. Especially useful in focal-onset SE, hepatic disease (no liver concern), or when minimal drug interactions are needed (no CYP effect, compatible with chemo, immunosuppressants, DOACs, OCPs). Watch for PR prolongation, get baseline ECG; avoid in 2°/3° AV block.
ESETT 2019: all three equally effective (~50% seizure termination at 60 min). Choice is driven by patient factors (pregnancy, liver disease, cardiac comorbidities, drug interactions). Lacosamide is an off-label fourth option supported by post-ESETT consensus and observational data.
40 Minutes -Phase 3: Refractory SE → ICU + Anesthetic
Intubate + continuous EEG. Target burst suppression for 24–48h, then slowly wean.
Options:
Propofol (Diprivan) 1–2 mg/kg IV bolus then 1–15 mg/kg/hr drip. Watch for propofol infusion syndrome (PRIS) at > 5 mg/kg/hr for > 48h: lactic acidosis, rhabdo, hypertriglyceridemia, bradyarrhythmia, cardiac collapse. Cap dose if you can or rotate to midazolam.
Midazolam (Versed) 0.2 mg/kg IV bolus then 0.05–2 mg/kg/hr drip. Tachyphylaxis develops over hours-days; expect dose escalation.
Ketamine (Ketalar) 1–2 mg/kg IV bolus then 1.2–5 mg/kg/hr. NMDA antagonist (the receptor that's externalized in prolonged SE), neuroprotective, preserves hemodynamics, bronchodilator. Increasingly used early in refractory SE.
Pentobarbital (super-refractory): 5 mg/kg bolus then 1–5 mg/kg/hr. Reserve for failure of midazolam/propofol/ketamine; high hemodynamic and infectious complication burden.
Neurology and/or epilepsy consult. Continuous EEG mandatory to detect NCSE and guide treatment (clinical exam useless once paralyzed/sedated).
Concurrent -Find the Cause
CT head (hemorrhage, structural lesion), LP (meningitis/encephalitis -unless ICP elevated), metabolic panel, AED levels, toxicology screen, anti-NMDA/LGI1 antibodies if young woman with encephalopathy, EEG (NCSE).
💊 Medications & Doses
Medications Reference
Drug
Dose
Phase
Notes
Lorazepam (Ativan) 1ST LINE
0.1 mg/kg IV, max 4 mg per dose; repeat × 1 (max 8 mg total)
Phase 1 (IV)
First-line if IV access. Respiratory depression risk -have bag-mask ready. Alternative IV benzo: diazepam (Valium) 0.15–0.2 mg/kg IV, max 10 mg/dose, repeat × 1.
Midazolam (Versed) IM
10 mg IM (> 40 kg); 5 mg (13–40 kg)
Phase 1 (no IV)
RAMPART 2012: non-inferior to IV lorazepam. Faster than establishing IV access. Use the outer thigh.
Levetiracetam (Keppra) PREFERRED 2ND
60 mg/kg IV, max 4500 mg over 10 min
Phase 2
Preferred second agent. No hepatotoxicity, no CYP interactions, no cardiac monitoring needed. Can cause agitation.
Cardiac monitoring required (hypotension, arrhythmia during infusion). Give ≤ 150 mg PE/min. Use caution in severe liver disease (monitor free phenytoin levels), but not absolutely contraindicated in emergent SE.
Lacosamide (Vimpat) ALTERNATIVE
200–400 mg IV load over 5–15 min, then 100–200 mg IV/PO BID
Phase 2 (off-label SE)
Not in ESETT but increasingly used. Minimal drug interactions, no CYP effect, no respiratory depression, 1:1 IV→PO. PR prolongation, baseline ECG; avoid in 2°/3° AV block. Especially useful in focal SE, hepatic disease, or when LEV/VPA/PHT contraindicated.
Propofol (Diprivan)
2 mg/kg bolus, then 1–15 mg/kg/hr
Phase 3 (refractory)
Rapid, titratable. Propofol infusion syndrome risk at high doses/prolonged use. Requires intubation.
Ketamine (Ketalar)
1.5 mg/kg IV bolus, then 1.2–5 mg/kg/hr
Phase 3
NMDA antagonist. Emerging evidence for refractory SE. Bronchodilator. Preserves airway reflexes better. Less hemodynamic compromise.
Discharge & Outpatient AED Regimen
Acute SE termination buys you the moment; a take-home AED keeps the patient out of the next ED visit. Selection is driven by seizure type, comorbidities, pregnancy status, and interaction profile.
Step 1, Do They Even Need an AED?
Not every seizure patient needs a chronic AED. The decision rests on recurrence risk over the next 2 years.
Provoked seizure (alcohol withdrawal, hypoglycemia, hyponatremia, drug toxicity, fever in pediatrics): treat the cause, no chronic AED. Recurrence rate is low if the trigger is removed.
First unprovoked seizure with high-risk features (abnormal EEG with epileptiform discharges, MRI lesion, status presentation, prior brain insult): ~60% recurrence over 2 years → start AED. Why: the recurrence risk approximates the definition of epilepsy itself, so treatment is justified after a single event.
First unprovoked seizure, normal EEG/MRI, no prior brain insult: ~30% recurrence over 2 years → shared decision. Treating cuts recurrence by ~35%, but does not change long-term remission rate. Many neurologists hold back unless a second seizure occurs (the textbook definition of epilepsy).
Two or more unprovoked seizures (= epilepsy): AED indicated regardless of EEG/MRI.
Step 2, AED Selection by Seizure Type
First-line choice depends on whether the seizures are focal (start in one brain region) or generalized (involve both hemispheres from onset). Ordered most-to-least common in adults.
CBZ, phenytoin, lamotrigine, oxcarbazepine, gabapentin, can worsen myoclonus
Key principle: if you don't know whether seizures are focal or generalized, default to a broad-spectrum agent (levetiracetam, lamotrigine, valproate, topiramate, zonisamide). Narrow-spectrum drugs (CBZ, phenytoin, gabapentin) can worsen idiopathic generalized epilepsy and should not be empirically chosen.
Rare but life-threatening (STOP drug): SJS-like reactions, angioedema, severe thrombocytopenia. Suicidal ideation (AED class effect, FDA warning), screen for new mood changes. Behavioral SE (irritability, anxiety, depression, aggression, rarely psychosis) in ~10–15%, dose-limiting. Empirical pyridoxine (B6) 50–200 mg/day may help in ~30–50% (mechanism unclear, not repleting a true deficiency, supraphysiologic adjunct); switch to brivaracetam if no response in 2–4 weeks. Common but tolerable: somnolence/fatigue ~15%, headache, dizziness, asthenia. Renally cleared, dose-adjust for CrCl < 80.
Lamotrigine (Lamictal) FIRST-LINE
100–200 mg BID
Start 25 mg/day × 2 wk → 50 mg/day × 2 wk → titrate to target over 4–6 wk.
Stevens-Johnson syndrome / TEN if titrated too fast (especially with VPA, which doubles lamotrigine levels, halve the starting dose). Hemophagocytic lymphohistiocytosis (HLH, FDA 2018 boxed warning), fever + cytopenias + ↑ ferritin + ↑ triglycerides → STOP. DRESS, aseptic meningitis (rare). Suicidal ideation (class). Rash distinction: benign maculopapular rash ~10% (days 5–14 of titration); STOP if fever, mucosal involvement, blisters, or desquamation. Common: insomnia, headache, dizziness, ataxia, diplopia, blurred vision. Estrogen-containing OCPs ↓ lamotrigine ~50% during active pill weeks (cycling toxicity risk).
PR prolongation (baseline ECG; avoid in 2°/3° AV block). Rare but serious: DRESS, atrial fibrillation/flutter, syncope. Suicidal ideation (class effect). Common: dizziness, diplopia, ataxia, headache, nausea (slow titration mitigates). Renal dose adjust for CrCl < 30 (cap 300 mg/day). Minimal drug interactions, attractive in polypharmacy.
Oxcarbazepine (Trileptal)
300–1200 mg BID
Start 150 mg BID, titrate weekly.
SJS / DRESS / agranulocytosis (rare; HLA-B*1502 testing in Asian patients, cross-reactive with CBZ). Hyponatremia in ~25% (SIADH-like, dose-dependent, more in elderly), check Na 1–2 wk after start and after dose increases. Suicidal ideation (class). Mild CYP3A4 inducer at higher doses (still ↓ OCPs, less than CBZ). Common: dizziness, somnolence, diplopia, ataxia, nausea, rash ~5% (less than CBZ).
Carbamazepine (Tegretol)
200–600 mg BID
Start 200 mg BID. Level: 4–12 mcg/mL. Auto-induces own metabolism over 4–6 wk, levels drop after starting.
SJS/TEN, DRESS (HLA-B*1502 testing in Asian patients, FDA mandate). Agranulocytosis, aplastic anemia (rare, monitor CBC q3–6 mo); leukopenia ~10% (usually benign). Hepatotoxicity.Avoid in idiopathic generalized epilepsy (worsens absence/myoclonic). Fetal anomalies (NTDs ~1%, craniofacial, IUGR, FDA category D). SIADH / hyponatremia.Strong CYP3A4/2C9 inducer, drops OCPs, warfarin, DOACs, immunosuppressants, lamotrigine. Common CNS (peak-level dependent): ataxia, nystagmus, diplopia, blurred vision.
Valproate (Depakote ER)
500–1500 mg QD (ER) or 250–750 mg BID (IR)
Level: 50–100 mcg/mL. Check baseline LFTs, recheck if symptomatic.
Hepatotoxicity (especially < 2 yr, mitochondrial disease/POLG mutations, can be fatal). Pancreatitis (rare but fatal, check lipase if abdominal pain). Avoid in pregnancy (NTDs ~1–2%, lower offspring IQ ~9 points, FDA black box). Hyperammonemic encephalopathy can occur with normal LFTs and therapeutic VPA level (treat with L-carnitine). Carbapenem interaction drops VPA > 60% in 24h → breakthrough seizures (do not co-administer). PCOS / menstrual irregularity in adolescent girls. Common: thrombocytopenia, weight gain, alopecia, tremor.
Topiramate (Topamax)
100–200 mg BID
Start 25 mg QHS, titrate by 25–50 mg/wk.
Acute angle-closure glaucoma (FDA warning, typically first month, painful red eye + acute visual change → STOP and ophthalmology emergent). Cleft palate in pregnancy (FDA category D). Suicidal ideation, depression, mood changes. Word-finding difficulty / cognitive slowing (dose-limiting). Kidney stones, metabolic acidosis (non-AG, carbonic anhydrase inhibition), oligohidrosis. Reduced OCP efficacy at > 200 mg/day. Common: paresthesias ~50%, weight loss (helpful or harmful).
Phenytoin (Dilantin)
300 mg QD or 100 mg TID
Level: 10–20 mcg/mL total, 1–2 mcg/mL free. Saturable kinetics, small dose changes cause big level swings.
DRESS, SJS, lupus-like syndrome, lymphadenopathy (rare, life-threatening). Purple glove syndrome from IV extravasation (skin necrosis; use fosphenytoin instead). Fetal hydantoin syndrome (cleft lip/palate, IUGR, microcephaly, distal phalangeal hypoplasia). Cerebellar atrophy from chronic toxicity (sometimes irreversible). Megaloblastic anemia from folate inhibition. Strong CYP inducer (drops OCPs, warfarin, DOACs, immunosuppressants). Common: gingival hyperplasia, hirsutism, coarse facies, ataxia, nystagmus (peak-related), peripheral neuropathy, osteopenia (long-term, vit D catabolism). Free phenytoin levels in low albumin or uremia. Largely supplanted by Keppra/lamotrigine for chronic use.
Rare but serious: anaphylaxis, angioedema, bronchospasm. Suicidal ideation (class). Similar to Keppra (binds same SV2A target with higher affinity) but fewer behavioral side effects, useful when a patient cannot tolerate Keppra-induced irritability/depression. Common: somnolence ~15%, dizziness, fatigue, nausea.
Step 4, Special Populations
Pregnancy / women of childbearing age:
Preferred:lamotrigine or levetiracetam (lowest teratogenic risk in registries; major malformation rates ~2–3%, similar to baseline population).
Avoid:valproate (NTDs ~1–2%, lower offspring IQ ~9 points, FDA black box), topiramate (cleft lip/palate ~1–2%), phenobarbital, polytherapy (additive risk).
Folic acid 4 mg daily at least 3 months before conception (vs 0.4–0.8 mg in general population). Why: AEDs deplete folate, and high-dose folate cuts NTD risk in this population.
OCP interactions: enzyme inducers (CBZ, phenytoin, phenobarbital, oxcarbazepine, topiramate > 200 mg/day) ↓ ethinyl estradiol levels by 30–50% → contraception failure. Use IUD, depot medroxyprogesterone, or higher-dose OCP. Conversely, estrogen ↓ lamotrigine ~50% during active pill weeks.
Levels during pregnancy: volume of distribution and clearance increase. Lamotrigine and levetiracetam levels often drop 30–50% by third trimester, anticipate dose increases. Recheck levels q month and post-partum (taper back).
Elderly:levetiracetam or lamotrigine preferred. Lower interaction burden, less cognitive impact than CBZ/phenytoin/phenobarbital, no induction of warfarin/DOAC metabolism. Start at half the usual dose; renal clearance and protein binding both decline with age.
CKD:lacosamide (low renal clearance), lamotrigine (hepatic clearance), valproate (hepatic). Levetiracetam needs dose reduction (CrCl-based, drops to half-dose at CrCl < 50 and quarter-dose at CrCl < 30).
Don't skip these conversations, document each one:
Driving restrictions: state-specific. Most US states require 3–6 months seizure-free before driving; some mandate physician reporting (CA, DE, NJ, NV, OR, PA), others rely on patient self-reporting. Document the conversation in the chart, this is a med-legal flashpoint.
Adherence is the #1 cause of breakthrough seizures and SE. Pillbox, smartphone reminders, family involvement. Missed doses are NOT benign, AED levels can drop below threshold within 24–48h.
Triggers to avoid: sleep deprivation (single biggest after non-adherence), alcohol (especially binge → withdrawal seizures), recreational drugs, photic stimulation (in photosensitive epilepsy, ~5% of patients).
Bone health: long-term enzyme inducers (CBZ, phenytoin, phenobarbital, primidone) increase osteoporosis risk via vitamin D catabolism. DEXA every 2 years after 5+ years of therapy; vitamin D 1000–2000 IU + calcium 1000–1200 mg daily.
SUDEP counseling: sudden unexpected death in epilepsy occurs ~1 per 1000 patient-years, higher with uncontrolled GTC seizures. Best prevention is seizure freedom. Discuss bedside monitors, partner education, prone-sleep avoidance in high-risk patients.
Follow-up: neurology in 1–2 weeks, EEG (if not done), MRI brain (if not done). Recheck AED level at 1–2 weeks for narrow-TI drugs (phenytoin, valproate, CBZ).
Pregnancy planning: if patient is or could become pregnant, discuss preferred AEDs and high-dose folic acid before conception, not after.
Step 6, Drug-Drug Interactions to Watch
🚫 Carbapenem × valproate: meropenem, imipenem, ertapenem drop VPA serum levels by 60–100% within 24 hours, breakthrough seizures or SE even in well-controlled patients. Do not co-administer. Bridge to levetiracetam if a carbapenem is essential.
Lamotrigine × valproate: VPA inhibits glucuronidation, doubles lamotrigine half-life. Halve the lamotrigine starting dose and titrate even more slowly to avoid SJS/TEN.
Valproate as an inhibitor (raises other drug levels): VPA inhibits glucuronidation and CYP2C9, raising phenobarbital levels (sedation, respiratory depression risk) and warfarin levels (bleeding risk; recheck INR after starting/stopping VPA). Conversely, enzyme inducers (phenytoin, carbamazepine, phenobarbital, rifampin) lower VPA levels and can cause breakthrough seizures, recheck VPA level if any of these is started.
Lamotrigine × estrogen-containing OCPs: estrogen induces lamotrigine glucuronidation, level drops ~50% during the 3-week active pill phase, then rebounds during placebo week (toxicity risk). Adjust dose with cyclic OCP, or switch to continuous-cycle / progesterone-only contraception.
📋 On Rounds
On Rounds
📋 Sample Presentation
"Mr. Abreu is a 34-year-old with known epilepsy who was brought in with generalized tonic-clonic seizure activity for approximately 12 minutes prior to EMS arrival. He received midazolam 10 mg IM en route with partial response. In the ED he received lorazepam 4 mg IV -the seizure terminated after 3 minutes. He was then loaded with levetiracetam 60 mg/kg IV. His home levetiracetam level was undetectable -consistent with medication non-adherence as the precipitant. CT head is negative. He is currently post-ictal but following commands. EEG is monitoring for non-convulsive status. Neurology is following."
Pimp Questions
Why 5 minutes as the definition of status epilepticus?
Most self-limited seizures stop within 2–3 minutes. Beyond 5 minutes, spontaneous termination becomes unlikely AND neuronal injury from excitotoxicity begins. At 30 minutes, permanent injury is near certain. The operational definition was lowered from 30 to 5 minutes to encourage earlier intervention.
What is the preferred second-line AED and what trial established this?
All three agents are equally effective ESETT 2019 -approximately 50% success at 60 minutes. Levetiracetam is generally preferred due to favorable safety profile: no cardiac monitoring, no hepatotoxicity, fewer drug interactions.
A patient's seizures stopped but they haven't woken up. How long do you wait before worrying?
Post-ictal state typically resolves within 30-60 minutes. If the patient hasn't returned to baseline by 60 min → concern for non-convulsive status epilepticus (NCSE). NCSE = ongoing seizure activity on EEG without visible convulsions -the brain is still seizing but the body isn't moving. This occurs in up to 48% of patients after convulsive status. Get an EEG immediately if there's persistent AMS after apparent seizure cessation.
What is the correct sequence of medications in status epilepticus?
Stage 1 (0-5 min): Benzodiazepine -lorazepam 0.1 mg/kg IV (max 4 mg/dose, repeat × 1) OR midazolam 10 mg IM if no IV access. Stage 2 (5-20 min, BZD failed): Second-line AED -levetiracetam 60 mg/kg IV (max 4500 mg) OR fosphenytoin 20 mg PE/kg IV OR valproate 40 mg/kg IV. These are considered equivalent per ESETT, 2019 trial -choose based on patient factors (valproate: avoid in pregnancy/liver disease; fosphenytoin: avoid in heart block).
Clinical Examples
📋 Case 1, Convulsive SE from Non-Adherence
Patient: 28M with epilepsy on levetiracetam. Found seizing ~10 min ago. GTC activity ongoing on EMS arrival.
Key findings: No IV access initially. Glucose 110. Levetiracetam level undetectable.
Management:
Midazolam (Versed) 10 mg IM if ≥ 40 kg (5 mg if 13–40 kg), no IV needed. RAMPART, 2012
Establish IV; if seizure persists, levetiracetam (Keppra) 60 mg/kg IV (max 4500 mg) over 10 min
Check BMP (Na, Ca, Mg), tox screen, AED levels, CT head
Continuous EEG if not at baseline within 30–60 min (rule out NCSE)
Teaching point: Medication non-adherence is the most common cause of SE. IM midazolam is non-inferior to IV lorazepam and faster when IV access is unavailable.
📋 Case 2, Refractory SE Requiring Intubation
Patient: 52F with brain metastases. Seizing 25 min despite lorazepam (Ativan) 4 mg IV × 2 and levetiracetam (Keppra) 4500 mg IV.
Propofol (Diprivan) 1–2 mg/kg bolus then 1–15 mg/kg/hr, titrate to burst suppression on cEEG. Watch for propofol infusion syndrome (PRIS) at > 5 mg/kg/hr × 48h.
Alternative: midazolam (Versed) 0.2 mg/kg bolus then 0.05–2 mg/kg/hr, or ketamine (Ketalar) 1–2 mg/kg bolus then 1.2–5 mg/kg/hr (NMDA antagonist, preserves hemodynamics, increasingly used early)
Continuous EEG mandatory, clinical exam useless once sedated
Target burst suppression 24–48h, then slowly wean
MRI brain; neurosurgery and oncology consult
Teaching point: After second-line AED fails = refractory SE. Must have cEEG, cannot assess seizure activity clinically in sedated patients. ESETT, 2019 showed all three second-line AEDs equally effective (~50% cessation).
📋 Case 3, Non-Convulsive SE (NCSE)
Patient: 74M post-cardiac arrest with ROSC. Comatose at 24h. Subtle eye twitching and lip movements. No overt convulsions.
Key findings: Continuous EEG: electrographic seizures without motor correlate. NCSE in up to 30% of comatose ICU patients.
Management:
IV levetiracetam (Keppra) 60 mg/kg (less sedating, preferred post-arrest)
If seizures persist, add lacosamide (Vimpat) 200 mg IV or valproate (Depakote) 40 mg/kg IV (max 3000 mg)
Avoid overly aggressive sedation unless electrographic SE persists
Continue targeted temperature management per post-arrest protocol
Neurology consult for EEG interpretation
Teaching point: NCSE is extremely common and frequently missed. Any ICU patient with unexplained AMS or failure to wake up post-seizure needs an EEG. You cannot diagnose NCSE without EEG.
Monitoring
Continuous EEG
AED levels
Neuro exam q2-4h
Glucose
CK if prolonged seizure
⚡ Summary
Summary
Define It Early
Continuous seizure activity beyond 5 minutes, or two or more seizures without return to baseline in between.The threshold used to be 30 minutes and was lowered because seizures beyond about 5 minutes rarely self-terminate and every additional minute causes neuronal death. Time is neurons.
Give an Adequate Benzodiazepine Dose
Lorazepam 4 mg IV, or midazolam 10 mg IM if there is no IV access, repeated once after 5 minutes.Under-dosing is the single commonest error: a 2 mg dose that fails is usually an inadequate dose, not benzodiazepine failure, and it wastes the window in which the drug still works (GABA receptors internalize as the seizure continues, so later doses work less well).
Work Up in Parallel, Never in Sequence
Never delay the benzodiazepine to chase labs or imaging.Check glucose immediately, since hypoglycemia is instantly correctable, and give thiamine before glucose in anyone malnourished or alcohol-dependent. Send electrolytes, calcium, magnesium, toxicology and antiepileptic levels while treatment is under way.
Move to the Second Agent by 20 Minutes
Levetiracetam 60 mg/kg, fosphenytoin 20 mg PE/kg, or valproate 40 mg/kg.The ESETT trial found all three equivalent, at roughly 45 to 50% efficacy each, so choose by the patient: levetiracetam for renal and hepatic safety and no interactions, valproate not in pregnancy or liver disease, fosphenytoin not in hypotension or arrhythmia and always at a controlled infusion rate.
Third Line Is Anesthesia and Intubation
Refractory status means failure of a benzodiazepine plus one second-line agent.Intubate and start a continuous infusion of midazolam, propofol or pentobarbital, titrated on continuous EEG to seizure suppression or burst suppression. Expect hypotension and have vasopressors running. Watch for propofol infusion syndrome at high doses.
Do Not Miss Non-Convulsive Status
NCSE presents as altered mental status, confusion or subtle motor movements with no obvious convulsion, and it commonly follows apparently treated convulsive status.Only EEG diagnoses it.Any patient who does not return to baseline after a seizure needs an EEG, and treating the convulsion while leaving electrographic status running is a classic and costly miss.
Find the Precipitant
Antiepileptic non-adherence or a subtherapeutic level in a known epileptic is the commonest cause. Also alcohol or benzodiazepine withdrawal, stroke, intracranial hemorrhage, CNS infection, tumor, metabolic derangement (sodium, glucose, calcium), hypoxia and drug toxicity. Image and consider an LP once the seizure is controlled, since status is a presenting feature of meningitis and encephalitis.
Read the Post-Ictal Labs Correctly
A raised AST after a seizure is muscle, not liver: check CK and note that ALT and bilirubin stay normal, so labeling it hepatitis starts a pointless workup. Expect a transient lactic acidosis that clears within an hour and a raised prolactin if drawn within 10 to 20 min, which supports a true seizure over a psychogenic event. A raised white count is stress demargination, not necessarily infection, though it should not stop you looking for one.
Esophageal varices (portal hypertension from cirrhosis)
Gastric varices
Higher mortality, requires different initial management (octreotide + antibiotics)
Risk Stratification -Glasgow-Blatchford Score -need for endoscopic intervention or transfusion in upper GI bleed (score 0 = safe outpatient)
Used to determine if patients can be managed outpatient vs need urgent endoscopy. Score ≥ 1 → admission. Score 0 → consider outpatient management. Components: BUN, Hgb, SBP, HR, melena, syncope, hepatic disease, cardiac failure.
High-Risk Features Requiring ICU: Hemodynamic instability (HR > 100, SBP < 100), active hematemesis, Hgb < 7, coagulopathy, cirrhosis/varices, on anticoagulants, multiple comorbidities.
🧪 Workup & Diagnosis
Workup
CBC -Hgb/Hct (may be normal initially -equilibration takes hours), platelets
BMP -BUN (elevated in UGIB from digestion of blood -BUN:Cr > 20:1 = UGIB), creatinine
Coags -PT/INR, PTT, fibrinogen (especially if cirrhosis or on anticoagulants)
Type & Screen -always. Type & Cross if actively bleeding
LFTs -cirrhosis workup if variceal source suspected
Nasogastric lavage -controversial; positive (bloody or coffee-ground aspirate) confirms UGIB; negative does not rule out (30% false negative if duodenal source)
EGD (upper endoscopy) -diagnostic and therapeutic; perform within 24 hours (within 12h if hemodynamically unstable or actively bleeding)
🚨 Management
Management
Immediate Resuscitation
2 large-bore IVs (16G or larger). Airway assessment -intubate if massive hematemesis, AMS, or unable to protect airway. IV crystalloid bolus initially. Transfuse PRBCs if Hgb < 7 (target 7–9). Restrictive transfusion strategy TRIGGER, 2015Villanueva, 2013 improves survival in UGIB.
Variceal vs Non-Variceal Decision
Known cirrhosis or portal hypertension? → Assume variceal until proven otherwise → Start octreotide + IV ceftriaxone immediately (do NOT wait for scope). Non-variceal → IV PPI (pantoprazole) infusion.
PPI Infusion (Non-Variceal)
Pantoprazole 80 mg IV bolus, then 8 mg/hr infusion for 72 hours after endoscopy shows high-risk lesion (Forrest Ia/Ib/IIa) Lau, 2007. Reduces rebleeding from peptic ulcers. Start empirically before scope. Erythromycin 250 mg IV 30 min pre-EGD improves visualization Barkun, 2010.
Endoscopy (EGD)
Within 24 hrs for stable patients. Within 12 hrs for unstable. GI endoscopy team should be called early. Endoscopic hemostasis: epinephrine injection, hemoclip, thermal coagulation, band ligation (varices).
Refractory / Massive Bleeding
Second EGD attempt. IR for embolization (non-variceal). TIPS (transjugular intrahepatic portosystemic shunt) for refractory variceal bleed. Surgery (rare -last resort). Sengstaken-Blakemore tube as temporizing bridge for massive variceal bleed if scope unavailable.
Swipe for more examples
📋 Case 1, Non-Variceal Upper GI Bleed
Patient: 58M on aspirin + clopidogrel (Plavix), presents with melena × 2 days, hematemesis in ED. HR 112, BP 88/54, Hgb 6.8.
Immediate resuscitation:
2 large-bore IVs (18G or larger). Type & crossmatch.
IV LR bolus 1L. Transfuse 2 units pRBC (Hgb < 7, hemodynamically unstable).
Hold aspirin and clopidogrel -discuss with cardiology (balancing GI bleed vs stent thrombosis risk).
Octreotide (Sandostatin) 50mcg IV bolus → 50mcg/hr IF variceal bleed suspected (cirrhosis, known varices). Add ceftriaxone (Rocephin) 1g IV daily for SBP prophylaxis.
GI consult for EGD within 24h (within 12h if hemodynamically unstable after resuscitation).
Post-EGD: Ulcer with visible vessel found and clipped. Continue PPI IV drip × 72h → then PO PPI BID. Resume aspirin in 3-5 days (cardiovascular benefit > rebleed risk if indicated). Clopidogrel -discuss with cards about timing.
Glasgow-Blatchford Score: Determines need for intervention. Score 0 = safe for outpatient management. This patient scores high → inpatient + urgent EGD.
📋 Case 2, Variceal Bleed
Patient: 52M with cirrhosis (Child-Pugh C), presents with hematemesis of bright red blood. HR 128, BP 78/44.
Management:
Octreotide drip: 50 mcg IV bolus → 50 mcg/hr (reduces portal pressure).
Ceftriaxone 1g IV daily, antibiotic prophylaxis in cirrhotics with GI bleed (reduces mortality).
Emergent EGD within 12 hours. Band ligation of varices.
If rebleeding after banding → TIPS (transjugular intrahepatic portosystemic shunt).
Key lesson: In variceal bleeds, octreotide + antibiotics + EGD within 12h. Over-transfusing KILLS, target Hgb 7, not 10.
📋 Case 3, Lower GI Bleed
Patient: 75F on apixaban for AFib, presents with painless bright red blood per rectum × 6 hours. HR 95, BP 110/68, Hgb 8.2.
Management:
Hold apixaban. IV fluids, type and crossmatch.
No need for FFP/PCC unless actively hemorrhaging and hemodynamically unstable.
Colonoscopy within 24h → diverticular bleed identified → endoscopic clipping.
If massive ongoing bleed → CT angiography → IR embolization.
Resume anticoagulation in 7 days (balancing stroke risk vs rebleed risk).
Key lesson: Most lower GI bleeds stop spontaneously. Colonoscopy within 24h is diagnostic. Don't forget to restart anticoagulation, stroke risk often outweighs rebleed risk.
🔄 Updated Practice: Old teaching: IV PPI drip (pantoprazole 8 mg/hr) for 72 hours in all upper GI bleeds. Current practice: IV PPI bolus is reasonable pre-endoscopy, but the 72-hour drip is only needed if high-risk lesion found on EGD (active bleeding, visible vessel, adherent clot). Clean-base ulcers can switch to PO PPI immediately. Also: pre-endoscopy erythromycin (250 mg IV) improves gastric visualization -increasingly used as a prokinetic before EGD.
💊 Medications & Doses
Medications
Drug
Dose
Indication
Notes
Pantoprazole (Protonix)
80 mg IV bolus → 8 mg/hr × 72h
Non-variceal UGIB (high-risk)
Raises gastric pH → stabilizes clot. Start before EGD empirically. Switch to oral after 72h.
Octreotide (Sandostatin)
50 mcg IV bolus → 50 mcg/hr × 3–5 days
Variceal UGIB
↓ Splanchnic blood flow → ↓ portal pressure. Start as soon as variceal source suspected. Continue 3–5 days post-banding.
Ceftriaxone (Rocephin)
1 g IV daily × 7 days
Variceal UGIB (cirrhosis)
Prophylaxis against SBP and bacterial infections. Significantly reduces mortality. Start with octreotide immediately.
FFP / Vitamin K
FFP 2–4 units; Vit K 10 mg IV
Coagulopathy (INR > 1.5–2)
Reverse anticoagulation before endoscopy if significant coagulopathy. Vit K for warfarin reversal. 4-factor PCC if urgent.
"Mr. Nguyen is a 67-year-old on aspirin and ibuprofen for knee pain who presented with 2 episodes of hematemesis and melena with initial BP 88/60 and HR 118. He was resuscitated with 2L NS and 2 units of PRBCs, with hemodynamic stabilization. BUN was 44, creatinine 1.1 -BUN:Cr ratio of 40 consistent with UGIB. Hgb on arrival was 8.2, now 9.1 post-transfusion. He is on pantoprazole 8 mg/hr infusion. GI performed EGD this morning showing a 1.5 cm duodenal ulcer with a visible vessel -Forrest IIa. Hemostasis was achieved with hemoclip and epinephrine injection. He is on PPI infusion for 72 hours. H. pylori testing is pending."
Pimp Questions
Why is BUN:Cr > 20 suggestive of UGIB?
Blood in the upper GI tract is digested and absorbed as protein, resulting in elevated BUN from amino acid catabolism. Creatinine remains unchanged. This disproportionate BUN rise (BUN:Cr > 20:1) helps localize the bleed above the ligament of Treitz.
Why do cirrhotic patients with GI bleed get prophylactic antibiotics?
Cirrhotic patients with GI bleed have very high rates of bacterial infections (up to 35–66%), including SBP, bacteremia, and UTIs. These infections worsen outcomes and increase rebleed risk. Prophylactic antibiotics (ceftriaxone 7 days) Soriano 1992 reduce infections, rebleeding, and mortality -one of the clearest survival benefits in hepatology.
When do you do an EGD in upper GI bleed -and when should it be truly emergent?
Most upper GI bleeds: EGD within 24 hours of presentation (after resuscitation and hemodynamic stabilization). Emergent EGD (within 12h): hemodynamic instability despite resuscitation, suspected variceal bleed (cirrhosis + hematemesis), or ongoing active hemorrhage.
A cirrhotic patient with hematemesis -what 3 things must you do that differ from a non-variceal bleed?
(1) Octreotide drip (50 mcg IV bolus → 50 mcg/hr × 3-5 days) -splanchnic vasoconstriction, reduces portal pressure and variceal bleeding. Start immediately, before EGD. (2) Ceftriaxone 1g IV daily × 7 days -antibiotic prophylaxis reduces infection, rebleeding, and mortality in cirrhotic GI bleed (up to 20% have occult SBP). (3) Restrictive transfusion target -Hgb goal 7-8 (not 10). Over-transfusion increases portal pressure → more bleeding.
Clinical Examples
📋 Case 1, Variceal Bleed in Cirrhosis
Patient: 52M with alcohol-related cirrhosis (Child-Pugh C), presents with large-volume hematemesis and melena. History of prior variceal bleed 1 year ago, non-compliant with nadolol.
2 large-bore IVs, type and crossmatch, transfuse pRBCs target Hgb 7 (restrictive strategy) Villanueva, 2013
Octreotide 50 mcg IV bolus then 50 mcg/hr drip x 3-5 days (start BEFORE endoscopy)
Ceftriaxone 1g IV daily x 7 days (antibiotic prophylaxis in cirrhotic GI bleed reduces mortality)
Urgent EGD within 12h for band ligation. If bleeding uncontrolled: Blakemore tube as bridge to TIPS
Teaching point: In variceal bleeding, the triad is: restrictive transfusion (Hgb 7), octreotide, and antibiotics. Over-transfusion increases portal pressure and worsens bleeding.
📋 Case 2, Peptic Ulcer Bleed on Anticoagulation
Patient: 71F with Afib on apixaban 5 mg BID and aspirin 81 mg daily (recent drug-eluting stent 3 months ago), presents with coffee-ground emesis and black tarry stools x 2 days.
Key findings: HR 102, BP 108/62, Hgb 7.8 (baseline 12.4), BUN 48, Cr 1.1. Glasgow-Blatchford score: 12. EGD: 1.5 cm duodenal ulcer with visible vessel (Forrest IIa).
Management:
Hold apixaban and aspirin. Consider andexanet alfa only if life-threatening bleed requiring emergent intervention
IV PPI: pantoprazole 80 mg bolus then 8 mg/hr drip x 72h after endoscopic hemostasis
EGD within 24h: dual therapy (epinephrine injection + thermal coagulation or clips) for Forrest Ia, Ib, IIa
Restart apixaban within 7 days (delay increases stroke risk more than bleed risk). Resume aspirin only if < 6 months post-stent
Teaching point: The decision to restart anticoagulation after GI bleed is critical. Delaying beyond 7 days significantly increases thromboembolic events. IV PPI drip is only indicated after endoscopic therapy for high-risk ulcer stigmata.
📋 Case 3, Low-Risk UGIB Managed as Outpatient
Patient: 34M with no significant PMH, presents to ED with one episode of coffee-ground emesis after heavy NSAID use for back pain. No hemodynamic instability, no melena.
Key findings: HR 76, BP 128/78, Hgb 14.2. BUN/Cr normal. Glasgow-Blatchford score: 0 (HR < 100, Hgb > 13 in male, BUN < 18.2, SBP > 109, no syncope/melena/liver disease/heart failure).
Management:
Glasgow-Blatchford score of 0 = very low risk. Can safely discharge with outpatient EGD Stanley, 2009
Start PO PPI: pantoprazole 40 mg BID. Stop NSAIDs. Outpatient EGD within 1-2 weeks
H. pylori testing at time of EGD. If positive, triple therapy for eradication
Teaching point: Glasgow-Blatchford score of 0 identifies patients who can be safely discharged. It outperforms clinical judgment for identifying low-risk patients who do not need admission or urgent endoscopy.
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
⚡ Summary
Summary
Resuscitate First, Scope Second
Two large-bore IVs, type and cross, fluids and blood.Endoscopy on an unresuscitated, hypotensive patient is dangerous and diagnostically poor.Aim for endoscopy within 24 h, and within 12 h for variceal bleeding or hemodynamic instability.
Transfuse Restrictively
Target hemoglobin above 7 g/dL (above 8 in active coronary disease). Liberal transfusion increases mortality in upper GI bleeding, particularly in cirrhosis, where raising the volume raises portal pressure and provokes rebleeding (Villanueva). The first hemoglobin is falsely reassuring in acute bleeding, since hemodilution has not yet occurred.
Split the Causes at the Door
Non-variceal, about 80%: peptic ulcer, erosive disease, Mallory-Weiss, malignancy, Dieulafoy lesion, angiodysplasia. Variceal, about 20%, in portal hypertension. The two are managed with different drugs from the first hour, so decide which you are treating before ordering.
Non-Variceal: PPI, But Not Reflexively for 72 Hours
An IV PPI bolus before endoscopy is reasonable and downstages the lesion. The 72-hour infusion is only needed if a high-risk lesion is found at endoscopy, an actively bleeding vessel, a visible vessel or an adherent clot. A clean-based ulcer needs no drip and can often be fed and discharged early. The mechanism is raising gastric pH so platelet aggregation and clot stability are possible.
Variceal: Octreotide and Antibiotics Before the Scope
Octreotide bolus then infusion to reduce splanchnic flow and portal pressure. Ceftriaxone for every cirrhotic with GI bleeding, which independently improves survival and reduces rebleeding: bacterial translocation during a bleed is common and infection worsens it. Band ligation at endoscopy, then non-selective beta blockade for secondary prophylaxis, and consider early TIPS in high-risk patients.
Know Who Needs the ICU
Hemodynamic instability (HR above 100, systolic below 100), active hematemesis, hemoglobin below 7, coagulopathy, cirrhosis or varices, anticoagulant use, or multiple comorbidities.Use Glasgow-Blatchford to identify the very low-risk patient who can be managed as an outpatient: a score of 0 to 1 has a very low chance of needing intervention.
Reverse Anticoagulation Proportionately
Reverse for life-threatening bleeding, not for every abnormal number.Warfarin: 4-factor PCC plus vitamin K. Dabigatran: idarucizumab. Factor Xa inhibitors: andexanet or PCC.Do not correct the INR in a cirrhotic reflexively: hemostasis there is rebalanced, and plasma raises portal pressure. Plan when anticoagulation restarts before the patient leaves, since the thrombotic indication has not gone away.
Finish the Job Before Discharge
Test and treat H. pylori in every peptic ulcer, and confirm eradication afterward, because untreated infection is the main driver of recurrence. Stop the NSAID, or add a PPI if it is essential.A gastric ulcer needs repeat endoscopy with biopsy in 6 to 8 weeks to exclude malignancy. Melena can persist for days after bleeding stops, so it is not by itself evidence of ongoing hemorrhage; use the hemoglobin trend and the vital signs instead.
Return of spontaneous circulation is just the beginning. Post-cardiac arrest syndrome causes multi-organ dysfunction. Targeted temperature management, hemodynamic optimization, and finding the cause define survival and neurologic outcome.
12-lead ECG (STEMI → cath lab without delay), ABG, labs, portable CXR, bedside echo. Establish arterial line + central line. If still on scene -transport immediately. For OHCA without ST elevation, immediate angiography is NOT required -COACT, 2019 showed no benefit to immediate cath in non-STEMI arrest.
Airway & Ventilation
Confirm ETT position. Target SpO₂ 94–98% -do NOT hyperoxia (increases reperfusion injury). Target PaCO₂ 35–45 mmHg -avoid hypocapnia (causes cerebral vasoconstriction). Titrate FiO₂ to achieve SpO₂ target, not 100%.
The goal is preventing fever, not inducing hypothermia.TTM-2 2021 found no benefit of 33°C over normothermia, so the old 32-36°C target range is superseded and routine cooling to 33°C is no longer the default. Current standard (ERC-ESICM 2021, AHA): keep comatose survivors under continuous temperature monitoring, actively prevent fever (T > 37.7°C) for at least 72 hours from ROSC, using a controlled device rather than relying on antipyretics. Why the device stays on: post-rewarming rebound fever is common and each degree above target worsens secondary brain injury. If a lower target is chosen for an individual patient, keep it controlled for ≥ 24 hours and rewarm slowly (≤ 0.25-0.5°C/h). Cooling blankets, Arctic Sun, or intravascular devices all work.
Seizure Management
Continuous EEG monitoring -up to 30–40% have post-arrest seizures including NCSE. Treat seizures aggressively. Prophylactic AEDs not recommended routinely but use if clinical or EEG seizure.
Neurological Prognostication
Wait ≥ 72 hours after rewarming before prognostication (sedation/hypothermia confound exam). Use multimodal approach: neuro exam (pupillary reflex, corneal reflex, motor response), SSEP (bilateral absent N20 = poor prognosis), EEG, CT/MRI brain, NSE (serum marker). No single test is definitive.
Secondary Prevention ICD & Disposition
Every VT/VF survivor needs ICD evaluation before discharge unless the arrest was due to a completely reversible cause. Missing this step is a common disposition error and can be fatal, since recurrence risk is substantial.
Secondary prevention ICD is a Class I indication for any survivor of sudden cardiac arrest (VF or hemodynamically unstable sustained VT) NOT due to a transient or reversible cause. Trial basis: AVID 1997, CIDS 2000, CASH 2000, all showed ICD superior to amiodarone for secondary prevention.
When ICD IS indicated (Class I)
Survivor of VF or hemodynamically unstable VT NOT from a clearly reversible cause
Sustained VT with structural heart disease (ischemic or non-ischemic cardiomyopathy), whether or not hemodynamically tolerated
Syncope with inducible sustained VT on EP study in a patient with structural heart disease
Genetic arrhythmia syndromes with prior cardiac arrest: long QT, Brugada, ARVC, CPVT, HCM with prior arrest
When ICD is NOT indicated (reversible causes)
Acute MI with complete revascularization and no residual ischemia, VF within 24-48h of MI is often attributable to acute ischemia alone and doesn't by itself mandate secondary ICD
Electrolyte derangement (severe hypokalemia, hypomagnesemia), fully corrected, no structural substrate
Drug-induced QT prolongation, offending drug stopped and QTc normalized off the agent
Commotio cordis (blunt chest impact causing VF), structurally normal heart, no long-term risk
Severe acid-base or metabolic disturbance, cause identified and corrected
Illicit drug-induced arrest (cocaine, methamphetamine) with structurally normal heart and commitment to abstinence
Timing rules before implantation:
Post-MI primary prevention: wait ≥ 40 days if EF persistently ≤ 35% (DINAMIT 2004, IRIS 2009, no benefit from earlier ICD). But secondary prevention ICDs can go in sooner if the arrest was NOT attributable to the acute MI itself.
Post-revascularization (CABG/PCI): wait ≥ 90 days before primary prevention ICD assessment, EF often recovers with revascularization.
New cardiomyopathy (ischemic or non-ischemic): ≥ 3 months of maximally tolerated GDMT before primary prevention ICD assessment, 30-40% of patients recover EF above 35% on GDMT.
Neurologically devastated survivors: defer ICD, prognostication must first confirm meaningful neurologic recovery. Implanting in a patient who will not wake up is not appropriate.
Before-Discharge Checklist
EP consultation to decide ICD vs no ICD
Echocardiogram to document EF (primary vs secondary prevention logic differs)
Coronary angiography (if not already done) to rule out ischemic substrate
Family history + genetic testing if channelopathy or ARVC suspected; family screening
GDMT initiation if structural heart disease (ARNI/ACEi/ARB, BB, MRA, SGLT2i)
Wearable cardioverter-defibrillator (LifeVest) bridge if ICD decision deferred (pending GDMT trial, revascularization recovery, neurologic prognostication), VEST 2018 evidence mixed; used pragmatically in many centers.
Return precautions and AED-at-home counseling for the family
💊 Medications & Doses
Medications
Drug
Dose
Role
Notes
Norepinephrine (Levophed)
0.1–1 mcg/kg/min
Vasopressor (first-line)
Maintain MAP ≥ 65–70 post-ROSC. Post-arrest myocardial dysfunction is common -monitor CO.
Dobutamine (Dobutrex)
2–15 mcg/kg/min
Post-arrest cardiogenic shock
Add if MAP adequate but echo shows severely reduced EF. Titrate to echo/clinical response.
Propofol (Diprivan)
5–50 mcg/kg/min
Sedation during TTM
Reduces shivering, facilitates temperature control. Monitor for propofol infusion syndrome.
Meperidine / Buspirone
Meperidine 25–50 mg IV PRN
Anti-shivering during TTM
Shivering increases metabolic demand and raises temperature. Treat aggressively. Magnesium also helps.
Aspirin + Heparin
Per ACS protocol
If ACS precipitant
Do not withhold antiplatelet/anticoagulation for neurologic concerns alone. Treat the cause.
Insulin infusion
Target BG 140–180 mg/dL
Glycemic control
Avoid both hypoglycemia and severe hyperglycemia. Tight control (< 110) increases hypoglycemia and worsens outcomes.
📋 On Rounds
On Rounds
Pimp Questions
Why do we avoid hyperoxia post-ROSC?
Hyperoxia (PaO₂ > 300 mmHg) worsens cerebral reperfusion injury through free radical generation. Multiple observational studies Kilgannon 2010 show increased mortality with hyperoxia post-ROSC. Target SpO₂ 94–98%, not 100%. Titrate FiO₂ down as soon as possible after ROSC.
When can you prognosticate neurological outcome after cardiac arrest?
Not before 72 hours after rewarming from hypothermia. Sedation, hypothermia, and metabolic derangements all suppress neurological function and mimic poor prognosis. Early withdrawal based on exam alone leads to self-fulfilling prophecy. Use multimodal assessment: neuro exam + SSEP + EEG + MRI brain + NSE levels.
What is targeted temperature management (TTM) and what does current evidence say?
TTM2, 2021: targeted hypothermia at 33°C did NOT improve survival or neurologic outcome compared to normothermia (targeting ≤ 37.5°C and actively preventing fever). This changed practice -the benefit is from preventing fever, not inducing hypothermia. Current approach: avoid fever aggressively (target ≤ 37.5°C × 72h). If using active cooling, 33°C × 24h is still acceptable. Rewarm slowly (0.25°C/hr).
When can you prognosticate neurologic outcome after cardiac arrest, and what tools do you use?
Wait ≥ 72 hours after rewarming (if TTM used) or ≥ 72h from ROSC. Earlier assessment is unreliable due to sedation, hypothermia, and metabolic derangements. Multimodal approach (no single test is sufficient): (1) Clinical exam: absent pupillary and corneal reflexes at 72h + bilaterally absent motor response = poor prognosis. (2) EEG: burst suppression or status epilepticus at 72h
Clinical Examples
Case 1: ROSC After VF Arrest with STEMI
Presentation: 58M found unresponsive at home. EMS: VF, defibrillated × 2, ROSC after 18 minutes of CPR. Arrives intubated. 12-lead ECG shows inferior STEMI.
Priorities: Cath lab activated immediately, PCI does not wait for neurologic prognostication. Post-PCI, initiate TTM: target ≤ 37.5°C × 72h with active fever prevention per TTM2, 2021. Titrate FiO₂ to SpO₂ 94–98%, avoid hyperoxia and hypoxia. MAP ≥ 65 with Norepinephrine; add Dobutamine if echo shows post-arrest low EF.
Teaching point: STEMI post-arrest goes to the cath lab regardless of coma. Post-arrest myocardial stunning is reversible, echo EF often normalizes by 48–72h. Rewarm slowly (0.25°C/hr) to avoid rebound hyperthermia.
Case 2: Neurologic Prognostication, Day 3 Post-Arrest
Presentation: 65F, out-of-hospital VF arrest, ROSC after 12 minutes. TTM completed (fever prevention protocol). Now day 3 post-normothermia, still comatose. GCS 5 (E1V1M3). Absent pupillary reflexes bilaterally. EEG shows burst suppression pattern. Family asking about prognosis.
Management: Do not withdraw support yet, full 72h post-normothermia is mandatory. Convene multidisciplinary meeting (neurology, ICU, palliative). Absent bilateral N20 SSEPs + absent pupillary reflexes + burst suppression EEG = convergent poor prognosis. Family meeting with honest, compassionate goals-of-care discussion.
Teaching point: No single test predicts outcome, multimodal assessment required. Early withdrawal is a self-fulfilling prophecy.
Case 3: Hypoxic Cardiac Arrest from Opioid OD
Presentation: 45M found unresponsive, suspected fentanyl overdose. EMS: PEA, ROSC after 8 minutes of CPR and Naloxone administration. Non-shockable rhythm. Arrives intubated, GCS 6.
Priorities: No cardiac cause, PCI not indicated. ECG: no STEMI. Bedside echo: normal EF, no wall motion abnormality. CT head to rule out intracranial pathology. Target SpO₂ 94–98%, normocapnia (PaCO₂ 35–45). Fever prevention protocol initiated. Continuous EEG, treat seizures aggressively if present.
Goals of care: 8 minutes of CPR is relatively short, prognosis may be better than prolonged arrest. Defer prognostication ≥ 72h post-normothermia. If no meaningful neurologic recovery expected on reassessment, early goals-of-care conversation with family. Address substance use disorder, consider Buprenorphine initiation prior to discharge if recovery occurs.
Teaching point: Hypoxic arrests (OD, asphyxia) receive the same post-arrest bundle, TTM, avoid hyperoxia, EEG monitoring. The cause determines whether you go to the cath lab, not the post-arrest protocol itself.
📋 Sample Presentation
"Mr. Perez is a 55-year-old who suffered an out-of-hospital VF arrest with 18 minutes of CPR before ROSC. He was brought to our ICU intubated. Initial ECG showed STEMI -he underwent emergency PCI with drug-eluting stent to the RCA. He is on TTM protocol at 33°C, day 1. He is on NE 0.2 mcg/kg/min, MAP 68. Echo shows EF of 30% with inferior wall hypokinesis -on dobutamine 5 mcg/kg/min. SpO₂ 96% on FiO₂ 0.4, PaCO₂ 41. Continuous EEG shows no seizure activity. BG 152, on insulin drip. We will maintain cooling for 24 hours total, then rewarm at 0.5°C per hour. Neurological prognostication deferred for 72 hours post-rewarming."
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
⚡ Summary
Summary
ROSC Is the Start, Not the End
Post-cardiac arrest syndrome is a whole-body ischemia-reperfusion injury: brain injury, myocardial dysfunction, systemic inflammation resembling sepsis, and the persisting precipitating illness. Neurologic outcome, not survival to ICU, is the outcome that matters, and it is largely determined in the first 24 h.
ECG and Echo Immediately
STEMI means the cath lab now, even in a patient who looks neurologically devastated, since prognostication that early is unreliable and revascularization improves outcome. Echocardiography gives wall motion, RV dilation suggesting pulmonary embolism, tamponade and ejection fraction, all in minutes at the bedside.
Run the H's and T's Systematically
Hypoxia, hypovolemia, hydrogen ion (acidosis), hypo- and hyperkalemia, hypothermia, hypoglycemia; toxins, tamponade, tension pneumothorax, thrombosis (coronary and pulmonary), trauma.If you do not find the cause you cannot fix it, and the arrest will recur.
Do Not Hyperoxygenate or Hyperventilate
Target a saturation of 92 to 98%: hyperoxia worsens reperfusion injury.Target normocapnia, a PaCO₂ of about 35 to 45: hypocapnia causes cerebral vasoconstriction and worsens ischemia, and hypercapnia raises intracranial pressure. Wean the FiO₂ down deliberately rather than leaving the patient on 100% after ROSC.
Control Temperature Actively
Targeted temperature management with a constant target between 32 and 36°C, and above all avoid fever.TTM2 found 33°C was not superior to normothermia with active fever prevention, so the current emphasis is on preventing hyperthermia for at least 72 h rather than on deep cooling. Treat shivering, which raises metabolic demand and defeats the target.
Support the Hemodynamics and the Glucose
Target a MAP above 65, often higher if there is evidence of cerebral hypoperfusion, using fluids, norepinephrine and an inotrope for the stunned myocardium, which typically recovers over 24 to 72 h. Keep glucose in a moderate range and treat hypoglycemia promptly, and treat seizures, which are common and may be non-convulsive, so get an EEG in anyone who does not wake.
Do Not Prognosticate Too Early
Wait at least 72 h after return to normothermia, and longer if sedation may still be confounding the exam.Use multiple modalities: clinical examination, EEG, somatosensory evoked potentials, neuron-specific enolase and imaging. Early pessimism becomes a self-fulfilling prophecy, since it leads to withdrawal of the support that would have permitted recovery.
Plan Secondary Prevention Before Discharge
An ICD is a Class I indication for any survivor of sudden cardiac arrest from VF or hemodynamically unstable sustained VT not due to a transient or reversible cause (AVID, CIDS, CASH). The reversible-cause exception matters: an arrest from hyperkalemia or an acute STEMI treated by revascularization may not need a device. Arrange cardiology follow-up, family screening where an inherited channelopathy or cardiomyopathy is possible, and rehabilitation.
Neuropsychiatric dysfunction from liver failure. In cirrhosis it's often episodic and reversible -find and treat the precipitant. Acute liver failure (ALF) is a different, more dangerous beast requiring ICU and transplant evaluation.
🔍 Overview
HE vs ALF -Two Different Conditions
Hepatic Encephalopathy (HE): Neuropsychiatric complications in a patient with pre-existing liver disease (cirrhosis). Usually reversible. Graded West Haven criteria 1–4.
Acute Liver Failure (ALF): Rapid hepatic necrosis in a previously healthy liver: coagulopathy (INR > 1.5) + encephalopathy without prior liver disease. Medical emergency requiring ICU + transplant evaluation.
Precipitants of HE -TIPS Mnemonic
T -Toxins/drugs (opioids, benzos, sedatives), Transjugular shunts
I -Infection (SBP is most common! -always tap ascites), Increased protein load (GI bleed)
P -Portal shunting, Portosystemic shunts
S -Sodium low (hyponatremia), Surgical stress, Starvation
Always perform diagnostic paracentesis in cirrhotic patient with new/worsening HE. SBP is the most commonly missed precipitant. PMN > 250/mm³ → SBP → treat even without symptoms.
LFTs, INR/PT -severity of liver dysfunction (most critical for staging)
Ammonia -confirms HE but does NOT correlate well with grade. Trend more useful than single value.
BMP -Na (hyponatremia worsens HE), K, BUN/Cr (renal function -HRS?)
CBC -infection? thrombocytopenia (cirrhosis)?
Diagnostic paracentesis -PMN count > 250 = SBP (most commonly missed precipitant); do this early
Blood cultures + UA + urine culture -rule out infection triggering HE
CXR -pulmonary infection
Head CT -if focal neuro deficits or unclear diagnosis (rule out structural cause); not routine
For ALF -Additional
Acetaminophen level -most common cause of ALF in US (50%); check even without clear history
Toxicology screen -rule out other drug/toxin causes
Viral hepatitis panel (HAV IgM, HBsAg, HBV DNA, HCV RNA) -2nd most common etiology group
Autoimmune hepatitis (ANA, ASMA, IgG) -treatable, do not miss
Pregnancy test -AFLP and HELLP are obstetric emergencies
Wilson's disease (ceruloplasmin, Kayser-Fleischer rings, urine copper) -rare but treatable in young patients
Contact transplant hepatology early in ALF -before deterioration
🚨 Management
Management: Hepatic Encephalopathy
Find and Treat the Precipitant
This is the most important step. Treat infection (SBP, pneumonia, UTI). Stop offending medications. Correct electrolytes. Treat GI bleed. Relieve constipation. Correct dehydration.
Lactulose (First-Line)
Lactulose 25–30 g PO/NG q1–2h until bowel movement, then titrate to 2–3 soft stools/day. Mechanism: acidifies colon → traps NH4⁺ → reduces ammonia absorption. If no PO/NG: lactulose enemas 300 mL in 700 mL water retention enema q6h.
🔄 Updated Practice: Old teaching: lactulose enemas are first-line for hepatic encephalopathy. Current practice: oral or NG lactulose is first-line (titrate to 3-4 soft stools per day). Rectal lactulose enemas (300 mL in 700 mL water) are reserved for patients who cannot take oral medications (e.g., grade III-IV HE with aspiration risk). Rifaximin (Xifaxan) 550 mg BID is added for secondary prevention of recurrence.
Rifaximin (Second-Line / Maintenance)
Rifaximin 550 mg PO BID -non-absorbable antibiotic that reduces gut ammonia-producing bacteria. Added to lactulose for recurrent or refractory HE. Significantly reduces HE recurrence Bass, 2010.
Airway Protection
Grade 3–4 HE (stupor/coma) → high risk of aspiration. Consider intubation early for airway protection, especially before procedures (paracentesis, endoscopy, LP).
Swipe for more examples
📋 Case 1, Hepatic Encephalopathy Management
Patient: 62M with alcoholic cirrhosis (Child-Pugh C), brought in confused and somnolent. Asterixis present. NH3 68.
Grade: West Haven Grade 3 (somnolent but arousable, confused, asterixis).
Identify precipitant: Infection (SBP? UTI? Pneumonia?), GI bleed, constipation, medications (benzos, opioids), electrolyte derangement (hypokalemia, hyponatremia), non-compliance with lactulose. Check: CBC, BMP, UA, CXR, blood cultures, diagnostic paracentesis (ALWAYS if ascites -rule out SBP).
Treatment:
Lactulose (Kristalose) 30mL PO/NG q1-2h until first bowel movement → then titrate to 3-4 soft stools/day. Can give as enema (300mL in 700mL water) if unable to take PO.
Rifaximin (Xifaxan) 550mg PO BID -add for prevention of recurrence (not just acute treatment). Reduces recurrence by 58%.
Protein restriction is OUTDATED -maintain 1.2-1.5 g/kg/day protein. Malnutrition worsens encephalopathy.
🔄 Updated Practice: Old teaching: restrict protein intake in hepatic encephalopathy to reduce ammonia production. Current practice: protein restriction is HARMFUL, it worsens malnutrition (which is already severe in cirrhosis) and does NOT improve encephalopathy. Maintain protein intake at 1.2-1.5 g/kg/day. Branched-chain amino acid supplements may help in protein-intolerant patients.
Key: NH3 level does NOT correlate with severity and should NOT be trended. Treat the patient, not the number. Lactulose titrated to stool output is the cornerstone.
📋 Case 2, Refractory Hepatic Encephalopathy
Patient: 61M with cirrhosis (Child-Pugh C), on lactulose and rifaximin, still Grade 3 HE (somnolent, confused). Ammonia 142.
Key concept: FIND THE PRECIPITANT, not just increase lactulose.
Precipitant checklist:
GI bleed, do rectal exam. Melena?
Infection / SBP, diagnostic paracentesis if ascites
Constipation, when was last BM?
Electrolyte abnormalities, hypokalemia and alkalosis worsen HE. Alkalosis converts NH4+ to NH3 which crosses BBB.
Medications, benzos, opioids, PPIs. Stop all sedatives.
Dehydration / renal failure
Dietary protein excess, rare. Do NOT restrict protein; they need it.
Rifaximin 550 mg BID -non-absorbable antibiotic that reduces ammonia-producing gut bacteria. Add-on to lactulose for recurrent HE; reduces breakthrough episodes by ~50% and HE-related hospitalizations by ~50% per Bass NEJM 2010.
Treat the precipitant -GI bleed, infection (especially SBP), AKI/dehydration, electrolyte derangement (esp. hypokalemia → ↑ ammonia), constipation, sedatives, dietary protein load, TIPS-related, HCC. Without precipitant control, HE recurs regardless of lactulose dose.
Consider zinc supplementation (cofactor in the urea cycle; cirrhotics are commonly deficient and modest data support reduced HE recurrence with repletion).
Key Lesson: Refractory HE = hunt for the precipitant. The answer is almost never "more lactulose." Check for GI bleed, SBP, constipation, hypokalemia, and sedating medications.
📋 Case 3, HE Mimicker: Wernicke's Encephalopathy in Cirrhosis
Patient: 55M with alcoholic cirrhosis, admitted with confusion, ataxia, and nystagmus. Team starts lactulose for presumed HE. Ammonia is only 45 (mildly elevated, does not correlate with HE severity).
Clinical course: After 48h of lactulose, no improvement. Re-examine: classic triad of confusion + ataxia + ophthalmoplegia = Wernicke's encephalopathy from thiamine deficiency, NOT hepatic encephalopathy.
Treatment:
IV thiamine 500mg TID × 3 days → 250mg daily × 5 days (high-dose Caine criteria dosing).
Must give thiamine BEFORE glucose (glucose without thiamine precipitates Wernicke's).
Improvement expected within hours to days.
Key Lesson: Not all confusion in cirrhotics is HE. Wernicke's and HE overlap significantly in alcoholic liver disease. Always give IV thiamine empirically. Ammonia levels do NOT reliably diagnose or exclude HE.
Management: Acute Liver Failure (ALF)
ICU admission -all ALF patients
N-acetylcysteine (NAC) -for acetaminophen ALF (and emerging evidence for non-acetaminophen ALF). 150 mg/kg IV over 1h, then 12.5 mg/kg/hr × 4h, then 6.25 mg/kg/hr × 16h. Start immediately if APAP toxicity possible.
Liver transplant evaluation immediately -contact transplant center
Manage ICP (cerebral edema risk in ALF) -head of bed 30°, avoid hypotonic fluids, consider ICP monitoring
Correct coagulopathy only if actively bleeding (do NOT give FFP prophylactically -INR is prognostic)
Avoid
💊 Medications
Medications -Hepatic Encephalopathy
Drug
Dose
Route
Notes
Lactulose (Kristalose) 1ST LINE
30 mL PO q1–2h until first BM → titrate to 3–4 soft stools/day
PO/NG/PR
Cornerstone of HE treatment. Acidifies colon → traps NH4+ → reduces ammonia absorption. Enema (300 mL in 700 mL water) if unable to take PO. Titrate to stool output, NOT ammonia level.
Rifaximin (Xifaxan)
550 mg PO BID
PO
Non-absorbable antibiotic. Added to lactulose for recurrence prevention -reduces HE recurrence by 58% RFHE, 2010. Not just for acute treatment. Well tolerated, minimal systemic absorption.
Zinc sulfate
220 mg PO daily
PO
Zinc deficiency impairs the urea cycle, worsening ammonia metabolism. Adjunctive therapy. Common deficiency in cirrhosis.
LOLA (L-ornithine L-aspartate)
Per protocol
PO/IV
Adjunct therapy. Provides substrates for ammonia metabolism (urea cycle and glutamine synthesis). Evidence modest -use as add-on when lactulose + rifaximin insufficient.
Metronidazole (Flagyl)
250 mg PO TID
PO
Only if rifaximin unavailable. Reduces ammonia-producing gut bacteria. Limit duration -neurotoxicity with prolonged use (peripheral neuropathy, cerebellar dysfunction). Not first-line.
Protein restriction is OUTDATED. Maintain 1.2–1.5 g/kg/day protein. Malnutrition worsens encephalopathy and increases mortality. Branched-chain amino acids (BCAA) may be beneficial if intolerant of standard protein.
📋 On Rounds
On Rounds
Pimp Questions
How does lactulose work in hepatic encephalopathy?
Lactulose is metabolized by colonic bacteria to lactic acid and acetic acid, lowering colonic pH. This acidic environment converts NH3 (which freely crosses intestinal epithelium) to NH4⁺ (which is charged and cannot be absorbed). It also acts as an osmotic cathartic, reducing intestinal transit time and ammonia absorption.
Why should you NOT give FFP prophylactically in ALF?
The INR in ALF reflects global coagulation factor deficiency and is used as a prognostic marker (part of King's College criteria for transplant listing). Correcting the INR with FFP obscures this prognostic marker without proven clinical benefit. Reserve FFP for active bleeding or before invasive procedures only.
What are the precipitants of hepatic encephalopathy and what's the mnemonic?
HEPATICS:H emorrhage (GI bleed → protein load → ammonia) · E lectrolytes (hypokalemia → increased renal ammonia production; hyponatremia) · P roteins (excessive dietary protein -rare cause, over-taught) · A nything that causes dehydration (diuretics, vomiting, diarrhea) · T IPS (shunting portal blood past the liver) · I nfection/SBP (most commonly missed precipitant -always do paracentesis) · C onstipation (decreased ammonia elimination) · S edatives (benzodiazepines, opioids -enhanced GABA sensitivity in cirrhosis). Most important: SBP and infection -check paracentesis fluid in every cirrhotic with altered mental status, even without abdominal pain or fever.
Why do you not chase the ammonia number?
Ammonia levels do not correlate well with the severity of hepatic encephalopathy and should not guide treatment. Reasons: (1) Ammonia is only one of many neurotoxins in HE -manganese, mercaptans, short-chain fatty acids, and inflammatory cytokines all contribute. (2) Venous ammonia levels don't reflect brain ammonia (arterial is slightly more reliable but still imperfect)
Clinical Examples
📋 Case 1, Overt HE Precipitated by GI Bleed
Patient: 61M with alcohol-related cirrhosis (Child-Pugh B), presents with confusion and asterixis. Found to have melena. Family reports increasing somnolence over 24 hours.
Key findings: Temp 37.4°C, HR 104, BP 102/58. Disoriented to time and place, asterixis present, no focal neurological deficits. West Haven Grade III. Hgb 7.8 (baseline 10.2), ammonia 142, Cr 1.6. CT head: no acute abnormality.
Management:
Lactulose 30 mL PO/NG q1-2h until first bowel movement, then titrate to 2-3 soft stools/day
Treat precipitant: GI bleed workup, transfuse to Hgb 7, start octreotide and ceftriaxone
Check for other precipitants: infection (SBP screen with paracentesis), electrolytes (hypokalemia, hyponatremia), constipation, medications (benzodiazepines, opioids)
Teaching point: Always identify and treat the precipitant. GI bleed is a common trigger because blood in the gut is a massive protein/nitrogen load that gut bacteria convert to ammonia. The ammonia level does NOT guide treatment -- treat the clinical grade.
📋 Case 2, Lactulose-Refractory HE
Patient: 58F with NASH cirrhosis, admitted 3 days ago with Grade III HE. On lactulose 30 mL q6h with 3-4 stools/day but remains persistently confused and intermittently combative.
Key findings: Still disoriented, asterixis present, no improvement in West Haven grade despite adequate lactulose. All precipitants addressed: no infection, electrolytes corrected, no offending medications. Ammonia trending down but mental status unchanged.
Management:
Ensure lactulose is actually producing stools (not just charted). Consider lactulose enemas (300 mL in 700 mL water PR) if oral route inadequate
Add rifaximin 550 mg BID if not already on it
Consider zinc supplementation 220 mg BID (cofactor for urea cycle; often deficient in cirrhotics)
Rule out alternative diagnoses: Wernicke encephalopathy (give thiamine), subdural hematoma, metabolic encephalopathy, occult seizures (consider EEG)
Teaching point: When HE does not respond to lactulose, broaden the differential. Cirrhotic patients can have multiple simultaneous causes of altered mental status. Do not anchor on HE alone.
📋 Case 3, Covert HE Affecting Quality of Life
Patient: 64M with compensated HCV cirrhosis (Child-Pugh A), referred by hepatologist for cognitive complaints. Wife reports he has become forgetful, has difficulty managing finances, and had a minor car accident last month. No overt confusion or asterixis.
Key findings: Alert, oriented x3, no asterixis. However, psychometric testing (Stroop test, number connection test) is abnormal. Ammonia 68. MRI brain: no structural abnormality. Diagnosis: Covert (minimal) hepatic encephalopathy.
Management:
Start rifaximin 550 mg BID (shown to improve cognitive function and driving performance in covert HE)
Lactulose 15-30 mL titrated to 2-3 soft stools/day
Counsel on driving safety: covert HE significantly impairs reaction time and is a recognized cause of motor vehicle accidents
Optimize nutrition: adequate protein intake (1.2-1.5 g/kg/day -- protein restriction is HARMFUL and outdated). Consider branched-chain amino acid supplementation
Teaching point: Covert HE affects up to 80% of cirrhotic patients and significantly impairs quality of life. Protein restriction is a harmful myth -- adequate protein intake is essential. Always screen for driving safety concerns.
📋 Sample Presentation
"Mr. Alvarez is a 54-year-old with decompensated cirrhosis from alcohol who presented with confusion and asterixis. This represents Grade 2 hepatic encephalopathy. We performed diagnostic paracentesis on admission which showed PMN count of 312 -consistent with SBP. He was started on cefotaxime and albumin per SBP protocol. Ammonia on admission was 118. He was started on lactulose -currently having 2–3 soft stools per day. He is more alert today, following commands, with ammonia down to 74. We are adding rifaximin for recurrence prevention. Rifaximin was not on his outpatient regimen. Repeat paracentesis is planned on day 5 to confirm SBP resolution."
Person, place, time, situation. Serial number connection test if able to participate.
Lactulose stool output
Strict I&O tracking
Target 3–4 stools/day. Too few → increase lactulose. Excessive diarrhea → dehydration → worsens HE.
Ammonia level
On admission only
Do NOT trend ammonia -it does NOT correlate with severity. An initial elevated ammonia supports the diagnosis but serial levels do not guide treatment. Treat clinically.
BMP (K+, Na+, Cr, BUN)
Daily
Hypokalemia → metabolic alkalosis → increased renal ammonia production → worsens HE. Hyponatremia worsens cerebral edema. Cr for HRS surveillance.
Infection workup
On admission + any worsening
CBC, blood cultures, UA/UCx, CXR, diagnostic paracentesis (rule out SBP -most commonly missed precipitant). Repeat paracentesis with any AMS change.
Treat the patient, not the ammonia number. Lactulose titrated to stool output + finding/treating the precipitant are the cornerstones. If mental status is improving, the treatment is working regardless of what the ammonia says.
⚡ Summary
Summary
Two Different Diseases on One Page
HE in cirrhosis is episodic and reversible, and the job is to find the precipitant.Acute liver failure is a different and far more dangerous entity, needing ICU care and transplant evaluation, where the encephalopathy reflects cerebral edema rather than ammonia alone. Do not manage one as if it were the other.
Always Hunt the Precipitant
TIPS: Toxins (sedatives, opioids, alcohol), Infection (above all SBP), Portosystemic shunt, Systemic causes (GI bleed, constipation, dehydration, hypokalemia, alkalosis, renal failure). Refractory HE means the precipitant has not been found; the answer is almost never more lactulose.
Tap the Abdomen Every Time
Diagnostic paracentesis in any cirrhotic with new or worsening encephalopathy.SBP is the most commonly missed precipitant, and it is frequently silent, without fever or abdominal pain. PMN above 250/mm³ means treat, symptoms or not, with a third-generation cephalosporin plus albumin.
Lactulose by Mouth or Tube, Titrated to Stool
Oral or NG lactulose is first line, titrated to 3 to 4 soft stools per day.Old teaching used enemas first; they are now reserved for the patient who cannot take it enterally (300 mL in 700 mL water as a retention enema). It works by acidifying the colon so ammonia is trapped as ammonium and excreted, plus a cathartic effect. Too much lactulose causes dehydration and hypokalemia, which themselves worsen HE.
Add Rifaximin for Recurrence
Rifaximin 550 mg BID reduces recurrent episodes and hospitalizations when added to lactulose. It is poorly absorbed, so it acts locally on the gut flora that generate ammonia. It is an add-on, not a replacement: monotherapy has not been shown to match the combination.
Do Not Restrict Protein
Protein restriction is harmful. Cirrhotic patients are already severely malnourished and sarcopenic, and restricting protein accelerates muscle loss, which removes the main extrahepatic site of ammonia disposal and makes the encephalopathy worse. Target 1.2 to 1.5 g/kg/day, with a late evening snack to shorten the overnight fasting catabolism.
Do Not Manage by Ammonia Level
The ammonia correlates poorly with the grade of encephalopathy in cirrhosis, and it is easily raised by a tourniquet, a delayed sample or a fist clench. HE is a clinical diagnosis and a diagnosis of exclusion: check glucose, electrolytes, drugs and, where the picture does not fit, image the head, because a cirrhotic who falls can have a subdural hematoma.
Fix Potassium and Review Sedatives
Hypokalemia drives renal ammoniagenesis and shifts the equilibrium toward the diffusible form, so correcting it is genuinely therapeutic rather than incidental. Review every sedating medication, above all benzodiazepines and opioids, whose clearance is prolonged. Consider TIPS reversal or reduction in shunt-related HE, and refer for transplant assessment, since recurrent HE is a marker of decompensation and shortens survival.
RoundsRx Infographic Series · #41 · Gastro & Hepatology · PDF 144 KB
Text version
GI · Hepatology · One Pager
Hepatic Encephalopathy / ALF
Find the precipitant first -especially SBP. Tap ascites. Lactulose to 2–3 stools/day. Add rifaximin for recurrence. ALF → ICU + NAC + transplant evaluation.
⚡ Precipitants -TIPS
T -Toxins/drugs, TIPS shunts
I -Infection (SBP!), increased protein
P -Portal shunting
S -Sodium (hyponatremia), starvation
Also: constipation, dehydration, hypokalemia
🧪 Always Tap Ascites
PMN > 250/mm³ = SBP
Treat: cefotaxime 2g IV q8h + albumin 1.5 g/kg day 1, 1 g/kg day 3
The most common sustained cardiac arrhythmia. Management rests on three pillars: rate control, rhythm control (when appropriate), and stroke prevention with anticoagulation guided by CHA₂DS₂-VASc.
🔍 Overview
Definition
Atrial fibrillation (AF) is an irregularly irregular supraventricular tachyarrhythmia caused by chaotic atrial electrical activity. No organized P waves on ECG -replaced by fibrillatory waves with an irregular ventricular response.
Classification
Type
Definition
Paroxysmal
Self-terminates within 7 days (usually < 48h)
Persistent
Lasts > 7 days, requires intervention to terminate
Long-standing persistent
Continuous > 12 months
Permanent
Rate control accepted; no further attempts at rhythm control
Valvular AF
AF with moderate-severe mitral stenosis or mechanical heart valve → requires warfarin (not DOACs)
Post-operative -especially cardiac and thoracic surgery (30–50%)
PE -AF can be the first sign of PE
Sepsis / critical illness -new AF in ICU = search for underlying cause
OSA, obesity, advancing age, pericarditis
Always ask: What triggered this AF? New AF is often a symptom of something else (sepsis, PE, thyroid storm, ACS, volume overload). Treat the cause, not just the rhythm.
ECG Features
Absent P waves -replaced by irregular fibrillatory baseline
Irregularly irregular R-R intervals (the hallmark)
Narrow QRS (unless aberrant conduction or pre-existing BBB)
Ventricular rate typically 100–180 bpm if untreated (RVR)
⚡ Management
▶ How to Manage New AFib, Step by Step (tap to expand)
Three parallel questions to answer in every new AFib: (1) Is the patient stable? (2) Does the patient need anticoagulation? (3) Rate or rhythm? These are independent decisions, address each. The 2023 ACC/AHA AFib guideline lowered the threshold to consider rhythm control earlier (EAST-AFNET 4) and made catheter ablation first-line for symptomatic paroxysmal AF (EARLY-AF, STOP-AF).
Step 1: Is the patient hemodynamically unstable?
Unstable = SBP < 90, AMS, chest pain, acute pulmonary edema, or signs of shock. → Synchronized DC cardioversion immediately (120-200 J biphasic, sedate first). Do not delay for anticoagulation status, hemodynamic compromise overrides the embolism risk in the moment.
Step 2: Stable → workup for etiology
Test
Why
12-lead ECG
Confirm AFib (irregularly irregular, no P waves). Rule out flutter, WPW (delta wave), STEMI as trigger.
TSH
Thyrotoxicosis is a reversible cause of new AFib. Always check; missing it means treating downstream forever instead of fixing the trigger.
Echo (TTE)
Assess EF (drives rate control choice), valvular disease (mitral stenosis = warfarin-only), LA size (predicts ablation success), LV thrombus.
BMP + Mg
K+ and Mg are the #1 missed cause of refractory RVR. Target K+ > 4.0 and Mg ≥ 2.0 before declaring failed rate control.
BNP, troponin, CBC
BNP for HF severity; troponin for demand ischemia from RVR; CBC for anemia (anemic patients run faster).
Reversible triggers
Holiday heart (alcohol), OSA, pneumonia, PE, post-cardiac surgery, hyperthyroidism, sepsis. Treat the trigger first; many AFs resolve.
Step 3: Anticoagulation decision (CHA₂DS₂-VASc)
CHA₂DS₂-VASc
Action
Why
≥ 2 in men, ≥ 3 in women
Anticoagulate with DOAC (apixaban, rivaroxaban, dabigatran, edoxaban) preferred over warfarin
2023 ACC/AHA: DOAC is first-line for non-valvular AFib. Apixaban (5 mg BID; 2.5 mg BID if 2 of 3: age ≥ 80, Cr ≥ 1.5, weight ≤ 60 kg) has the best bleeding profile.
1 in men, 2 in women
Shared decision-making; most patients benefit from anticoagulation
Stroke risk ~1-2%/yr at this band; DOAC reduces it ~65%. 2023 guideline shifted toward favoring anticoag in this borderline group.
0 in men, 1 in women (woman's "1" is sex only)
No anticoagulation
Stroke risk < 1%/yr; bleeding risk on DOAC outweighs.
DOAC exceptions, use warfarin instead:
Mechanical heart valve (RE-ALIGN 2013: dabigatran caused excess strokes and bleeding vs warfarin).
Moderate-severe mitral stenosis (rheumatic), INVICTUS (2022) confirmed warfarin superior to rivaroxaban.
Antiphospholipid syndrome with triple-positive antibodies (TRAPS 2018: rivaroxaban inferior).
End-stage renal disease/dialysis: apixaban or warfarin; avoid other DOACs.
HAS-BLED is to mitigate modifiable bleeding risks, NOT to deny anticoagulation. Address: uncontrolled HTN, NSAIDs, alcohol, labile INR, before forgoing protection.
Step 4: Rate vs rhythm control (paradigm shift toward earlier rhythm)
Favor Rate Control
Favor Rhythm Control
Older (> 75), asymptomatic, long-standing AFib, large LA (> 5 cm)
Diltiazem (fast onset, COPD-safe) or metoprolol (also good for HTN/ACS)
Combination BB + non-DHP CCB only with caution (bradycardia); add digoxin if still high
Reduced EF (HFrEF, EF < 40%)
Metoprolol succinate, carvedilol, or bisoprolol (evidence-based for HFrEF)
Avoid non-DHP CCBs. Add digoxin (target 0.5-0.9 ng/mL) or amiodarone for refractory rate.
Critically ill / ICU
Esmolol (ultra-short β₁, stops fast if BP drops) or amiodarone if HFrEF or hemodynamically borderline
Avoid diltiazem in shock/sepsis (worsens BP).
Targets (RACE II, 2010):lenient HR < 110 at rest is non-inferior to strict < 80 for most patients with preserved EF and tolerable symptoms. Strict only if persistent symptoms despite lenient control.
Step 6: Rhythm control (if chosen)
Strategy
How
Why
Cardioversion (electrical or pharmacologic)
If onset < 48 hr: cardiovert with concurrent anticoagulation initiation. If ≥ 48 hr or unknown: ≥ 3 weeks of therapeutic anticoag OR TEE-guided to exclude LAA thrombus. Then continue ≥ 4 weeks anticoag post-cardioversion regardless of CHA₂DS₂-VASc.
Atrial mechanical stunning after cardioversion ↑ thrombus risk for weeks even with restored sinus. Long-term anticoag continues based on CHA₂DS₂-VASc, not the cardioversion success.
Antiarrhythmic drug (AAD)
No structural heart disease: flecainide or propafenone ("pill-in-pocket" possible). HFrEF or CAD: amiodarone (most effective, but toxic) or dofetilide (HFrEF safe, inpatient initiation). Avoid dronedarone in HFrEF (ANDROMEDA: harm). Sotalol if normal LV and QTc OK.
AADs in structural heart disease have proarrhythmic risk (CAST: Class IC ↑ mortality in post-MI). Choice driven by safety, not efficacy.
Catheter ablation
First-line for symptomatic paroxysmal AFib (EARLY-AF 2021, STOP-AF 2021); 2nd-line after AAD failure for persistent. Class I in HFrEF (CASTLE-AF 2018: 47% mortality reduction).
Modern ablation success ~70-80% at 1 year (paroxysmal), ~50-60% (persistent). The 2023 ACC/AHA guideline elevated ablation to first-line in paroxysmal symptomatic AFib.
Step 7: Refractory or anticoag-intolerant
Scenario
Do This
Why
Stroke risk high but DOAC contraindicated (recurrent major bleeding, intolerant)
LAA closure (Watchman, Amulet)
PROTECT-AF (2009), PREVAIL (2014), PRAGUE-17 (2020): LAA closure non-inferior to warfarin for stroke prevention with lower bleeding long-term. ~90% of AFib thrombi originate in the LAA.
Refractory rate despite all drugs
AV node ablation + permanent pacemaker ("ablate and pace")
Last resort for medication-refractory rate. Patient becomes pacemaker-dependent but rate is controlled.
Failed multiple ablations + AADs
Accept "permanent" AFib, optimize rate + anticoag
Some AFibs cannot be maintained in sinus; accept and protect from stroke and HF.
Shortcuts that override the ladder
Scenario
Do This
Why
AFib + WPW (delta wave, pre-excited tachycardia)
NEVER give AV-nodal blockers (diltiazem, verapamil, BB, digoxin, adenosine). Use procainamide or DC cardiovert.
Blocking the AV node forces conduction down the accessory pathway → can degenerate to VF and death. The AV node is the patient's safety valve here.
AFib + sepsis / pneumonia / PE
Treat the trigger first; gentle rate control with esmolol or amiodarone if needed
Most secondary AFib resolves with the trigger. Aggressive rate control with diltiazem in sepsis drops BP. Long-term anticoag decision deferred until reassessment after recovery.
Post-cardiac-surgery AFib
Rate-control short-term; anticoagulate if persists > 48 hr; expect resolution in > 80% by 6 weeks
POAF is usually self-limited inflammation. Long-term anticoag decision at 6 weeks based on rhythm status and CHA₂DS₂-VASc.
Tachycardia-mediated cardiomyopathy (new HFrEF + AFib RVR)
Rhythm control preferred, ablation often curative; EF may recover fully on sinus restoration
The cardiomyopathy is the AFib's consequence, not its cause. Restoring sinus is disease-modifying.
Pregnancy + AFib
Avoid DOACs and warfarin (warfarin teratogenic 6-12 weeks); use LMWH for anticoag. Metoprolol or digoxin for rate.
DOACs cross placenta (no safety data, contraindicated); warfarin teratogenic in first trimester. LMWH is the standard.
Holiday heart (alcohol-triggered AFib)
Abstinence is the intervention; cardiovert acute episode, no chronic anticoag if CHA₂DS₂-VASc 0-1 and triggers avoidable
Resolves with sobriety. Don't commit to lifelong anticoag from one trigger-driven episode.
Subclinical AFib found on device monitoring (pacemaker, ICD, Holter)
ARTESIA (2023): apixaban reduced stroke in subclinical AFib (episodes 6 min - 24 hr) but increased bleeding; balance individually. Episode duration matters.
AFib + recent ischemic stroke
Start DOAC at day 3-14 depending on infarct size (small → earlier; large → 7-14 days)
Hemorrhagic transformation risk early; stroke recurrence risk later. ELAN (2023) supported earlier (≤ 4 days) DOAC start in small-moderate strokes.
OSA + AFib
Treat OSA (CPAP); ablation success drops to ~20-30% without OSA treatment
Untreated OSA drives AFib recurrence even after successful ablation. CPAP improves rhythm-control success substantially.
Is the Patient Hemodynamically Unstable?
Unstable = hypotension (SBP < 90), AMS, chest pain, acute pulmonary edema, or signs of shock. If YES → immediate synchronized cardioversion. Do not delay for rate control medications.
Unstable → Cardiovert
Synchronized DC cardioversion -120–200J biphasic. Sedate first if possible (propofol, etomidate, or midazolam). If first shock fails, escalate energy. Have pads and airway equipment ready. This is immediate -do not wait for anticoagulation status.
Stable → Rate Control
If hemodynamically stable with RVR (HR > 110), proceed to pharmacologic rate control. Choice depends on EF:
Rate Control in Afib with RVR -By EF
Setting
First-Line
Dose
Notes
Preserved EF (HFpEF or normal)
Diltiazem
0.25 mg/kg IV over 2 min → repeat 0.35 mg/kg in 15 min if needed → drip 5–15 mg/hr
Fastest onset. Can also use metoprolol. Avoid in pre-excitation (WPW).
Preserved EF (alternative)
Metoprolol tartrate
5 mg IV push q5 min × 3 doses → 25–100 mg PO BID
Good if also hypertensive or ACS. Safer than diltiazem in borderline EF.
Reduced EF (HFrEF, EF < 40%)
Amiodarone
150 mg IV over 10 min → 1 mg/min × 6h → 0.5 mg/min × 18h
Avoid CCBs and high-dose BB in HFrEF. Amio provides rate + rhythm control. Monitor QTc.
Reduced EF (alternative)
Digoxin
0.25–0.5 mg IV load → 0.125–0.25 mg PO daily
Slow onset (hours). No acute rate control. Add-on for refractory rate. Check levels (0.5–0.9 ng/mL). RATE-AF, 2020: digoxin non-inferior to bisoprolol for rate control in permanent AF.
Critical illness / ICU
Amiodarone or esmolol
Esmolol: 500 mcg/kg IV bolus → 50–200 mcg/kg/min drip
Esmolol = ultra-short acting β₁ blocker. Ideal for hemodynamic uncertainty -stops fast if BP drops.
NEVER give CCBs (diltiazem, verapamil) or BB in Afib with WPW (pre-excitation / delta wave on ECG). These block the AV node → forces conduction down accessory pathway → VF → death. Use procainamide or cardiovert.
Targets
Strategy
Target HR
Evidence
Lenient (most patients)
< 110 bpm at rest
RACE II, 2010: lenient was non-inferior to strict. Less drug side effects. Preferred initial approach.
Strict (if symptomatic)
< 80 bpm at rest
Use if persistent symptoms despite lenient control.
Workup in New Afib with RVR
12-lead ECG -confirm AF, rule out flutter, WPW, STEMI
TSH -always check. Thyrotoxicosis is a reversible cause.
BMP -electrolytes (K⁺, Mg²⁺ -both must be repleted), renal function
BNP/Echo -assess EF. Determines drug choice (CCB vs amio).
AF duration < 1 year (higher success of maintaining sinus)
Tachycardia-mediated cardiomyopathy
EAST-AFNET 4, 2020: early rhythm control (within 1 year of diagnosis) reduced cardiovascular outcomes vs rate control alone
Cardioversion Rules
If AF > 48 hours (or unknown duration): Must anticoagulate ≥ 3 weeks before elective cardioversion OR do TEE to rule out LAA thrombus first. Then anticoagulate ≥ 4 weeks after cardioversion regardless.
If AF < 48 hours: Can cardiovert without prior anticoagulation (but start anticoagulation based on CHA₂DS₂-VASc after).
Antiarrhythmic Agents
Drug
Use
Key Caution
Flecainide (Tambocor) 1ST LINE
No structural heart disease ("pill-in-the-pocket" for paroxysmal AF)
Contraindicated in CAD, HFrEF, structural disease (proarrhythmic). Must give with AV nodal blocker.
Propafenone (Rythmol)
Same as flecainide -no structural disease
Same contraindications. Also has mild BB activity.
Amiodarone (Cordarone)
Structural heart disease, HFrEF -most versatile
Long-term toxicities (thyroid, pulmonary fibrosis, hepatotoxicity, corneal deposits). Not first-line in young patients.
QTc prolongation → Torsades. Must monitor QTc × 3 days inpatient. Renally dosed.
Sotalol
No severe structural disease. Combined BB + class III.
QTc prolongation. Avoid in HFrEF, renal failure. Monitor QTc closely.
Ibutilide
Acute pharmacologic cardioversion (IV only)
QTc prolongation → Torsades (risk ~4%). Monitor on telemetry × 4h. Have Mg²⁺ and defibrillator ready.
🔄 Updated Practice: Old teaching: rate control is preferred over rhythm control for most AF patients (based on AFFIRM, 2002). New evidence: EAST-AFNET 4, 2020 showed that EARLY rhythm control (within 1 year of diagnosis) reduces cardiovascular death, stroke, and HF hospitalization. Key word is "early" -the benefit diminishes if AF has been present for years. Consider early rhythm control especially in younger patients and those with HF.
💉 Anticoagulation & Stroke Prevention
CHA₂DS₂-VASc Score
Determines stroke risk and need for anticoagulation in non-valvular AF. Calculate for every AF patient.
Letter
Risk Factor
Points
C
Congestive heart failure (or LV dysfunction, EF ≤ 40%)
1
H
Hypertension (or on antihypertensive therapy)
1
A₂
Age ≥ 75 years
2
D
Diabetes mellitus
1
S₂
Stroke / TIA / thromboembolism (prior)
2
V
Vascular disease (prior MI, PAD, aortic plaque)
1
A
Age 65–74 years
1
Sc
Sex category -female
1
Maximum score: 9. Note: female sex alone (score = 1) does not warrant anticoagulation -it is a risk modifier, not an independent indication.
CHA₂DS₂-VASc and bridging(only relevant when AF anticoagulation is held for a procedure):
≥ 7 → bridge with LMWH (high thrombotic risk). Also bridge regardless of score if stroke/TIA within 3 months or rheumatic AF.
5–6 → individualize by the bleeding risk of the procedure (moderate risk).
≤ 4 → do NOT bridge -bridging low-risk AF adds bleeding with no reduction in stroke (BRIDGE, 2015).
Full periprocedural protocol: Anticoagulation Management → bridging.
⚠️ Anticoagulate regardless of CHA₂DS₂-VASc score -the following carry stroke risk so high that the score doesn't apply:
Hypertrophic cardiomyopathy (HCM) with AF -Class I (2024 AHA/ACC HCM guideline). DOAC preferred.
Cardiac amyloidosis with AF -anticoagulate even if sinus rhythm if intracardiac thrombus on imaging.
Moderate-to-severe (rheumatic) mitral stenosis -warfarin only, NOT DOACs.
Mechanical heart valve -warfarin only (RE-ALIGN: dabigatran failed).
LA / LAA thrombus on TEE or cardiac CT -anticoagulate regardless of rhythm.
Peri-cardioversion -anticoagulate ≥ 3 weeks before + 4 weeks after, or TEE-guided.
Anticoagulation Decision
Score (Male / Female)
Annual Stroke Risk
Recommendation
0 (M) / 1 (F)
~0.2–0.6%
No anticoagulation recommended
1 (M) / 2 (F)
~1.3–2.2%
Consider anticoagulation (discuss with patient -benefit may outweigh bleed risk)
≥ 2 (M) / ≥ 3 (F)
~2.2–15%
Anticoagulate. DOACs preferred over warfarin for non-valvular AF.
Anticoagulant Options
Drug
Dose
Key Points
Apixaban (Eliquis) PREFERRED
5 mg PO BID (2.5 mg if ≥ 2 of: age ≥ 80, weight ≤ 60 kg, Cr ≥ 1.5)
Preferred DOAC. Lowest bleeding risk. ARISTOTLE, 2011: superior to warfarin for stroke prevention with less bleeding.
Rivaroxaban (Xarelto) ALTERNATIVE
20 mg PO daily with dinner (15 mg if CrCl 15–50)
Once daily. ROCKET-AF, 2011: non-inferior to warfarin. Must take with food for absorption.
Dabigatran (Pradaxa) ALTERNATIVE
150 mg PO BID (75 mg if CrCl 15–30)
RE-LY, 2009: 150 mg dose superior to warfarin for stroke; higher GI bleed. Reversible with idarucizumab.
Edoxaban (Savaysa)
60 mg PO daily (30 mg if CrCl 15–50, weight ≤ 60 kg, or P-gp inhibitor)
ENGAGE AF-TIMI 48, 2013: non-inferior to warfarin. Do NOT use if CrCl > 95 (reduced efficacy).
Warfarin (Coumadin) VALVULAR ONLY
Titrate to INR 2.0–3.0
Required for valvular AF (mechanical valve, moderate-severe mitral stenosis). TTR > 70% needed for benefit. Bridging with heparin may be needed.
Valvular AF = warfarin only. DOACs are NOT approved for mechanical heart valves (RE-ALIGN, 2013: dabigatran increased thromboembolism and bleeding vs warfarin in mechanical valves -trial stopped early) or moderate-severe mitral stenosis.
🔄 Updated Practice: Old teaching: warfarin is the standard anticoagulant for AF. Current practice: DOACs (apixaban, rivaroxaban, dabigatran, edoxaban) are preferred over warfarin for non-valvular AF -better safety profile, no INR monitoring, fewer drug-food interactions. Warfarin is still required for: mechanical heart valves (RE-ALIGN -DOACs caused thromboembolism), moderate-severe mitral stenosis, and antiphospholipid syndrome (TRAPS -DOACs increased thrombosis).
HAS-BLED Score (Bleeding Risk)
Use to identify modifiable bleeding risk factors -NOT to withhold anticoagulation. A high HAS-BLED score means fix the modifiable risks, not stop the DOAC.
Score ≥ 3 = high bleeding risk. Address modifiable factors (control BP, stop NSAIDs, reduce alcohol, optimize INR). Do not withhold anticoagulation based on HAS-BLED alone.
Swipe for more examples
📋 Case 1, New Afib with RVR Management
Patient: 72F presents with palpitations, HR 142, irregularly irregular, BP 108/72. No prior Afib history.
Step 1 -Rate Control:
Metoprolol (Lopressor) 5mg IV push over 2 min. Repeat q5min × 3 doses (max 15mg). HR → 118.
Additional: metoprolol (Lopressor) 5mg IV → HR 98. Start metoprolol tartrate (Lopressor) 25mg PO q6h.
If HFrEF (EF < 40%): Avoid diltiazem -contraindicated (negative inotrope worsens HF). Use amiodarone (Cordarone) 150mg IV over 10 min → 1mg/min × 6h → 0.5mg/min × 18h. If preserved EF but hypotensive: diltiazem (Cardizem) 0.25 mg/kg IV bolus → drip 5-15 mg/hr is acceptable.
Step 2 -Anticoagulation: CHA₂DS₂-VASc: Age 72 (+1), Female (+1) = 2 → Anticoagulate.
Start apixaban (Eliquis) 5mg PO BID (preferred DOAC). Reduce to 2.5 mg BID if ≥ 2 of: age ≥ 80, weight ≤ 60 kg, Cr ≥ 1.5 mg/dL. Note: 2 of 3, not all 3, residents commonly miss this and underdose.
Step 4 -Rate vs Rhythm Control:
New-onset, symptomatic → consider cardioversion if < 48h onset OR TEE-guided if > 48h. Otherwise rate control + anticoagulation × 3 weeks → then cardioversion.
📋 Case 2, Afib with WPW (Pre-excitation)
Patient: 32M presents with HR 220, irregular wide-complex tachycardia. Known WPW. BP 100/62. ECG shows irregularly irregular wide QRS with varying morphology.
CRITICAL, Do NOT give AV nodal blockers:
No diltiazem, no metoprolol, no digoxin, no adenosine. These block the AV node and force conduction down the accessory pathway → can degenerate to VF.
Treatment:
Procainamide 20-50 mg/min IV (slows accessory pathway conduction).
If unstable → synchronized cardioversion.
If VF → defibrillate immediately.
Key Lesson:
Irregular wide-complex tachycardia = Afib with WPW until proven otherwise. AV nodal blockers can kill. Procainamide or cardiovert.
📋 Case 3, New Afib in Sepsis
Patient: 68F admitted with pneumonia and septic shock, develops new Afib with RVR (HR 148). No prior cardiac history. This is likely rate-related, not a primary arrhythmia.
Treatment, Treat the underlying cause FIRST:
Fluids, antibiotics, source control. The Afib is a symptom of the sepsis, not the primary problem.
Rate Control:
Esmolol drip (short-acting, titratable), better than diltiazem in sepsis because diltiazem drops BP. Target HR < 110 (not < 80).
Do NOT cardiovert:
Rhythm will likely convert once sepsis resolves.
Anticoagulation: CHA₂DS₂-VASc assessment, but defer starting anticoagulation until sepsis is stabilized.
Key Lesson:
New Afib in sepsis is usually a symptom, not the disease. Treat the infection. Use esmolol for rate control. Don't chase rhythm conversion.
🧪 Workup
Initial Workup -New Atrial Fibrillation
12-lead ECG -confirm AF (irregularly irregular, no P waves). Rule out flutter, WPW (delta wave).
TSH -hyperthyroidism is a reversible cause. Check in ALL new AF.
CBC -anemia can worsen rate, infection can trigger AF
TTE (echocardiogram) -assess LV function (EF), valvular disease, LA size, wall motion abnormalities
Troponin -if chest pain or concern for ACS as trigger
BNP/NT-proBNP -if concern for heart failure
Consider: D-dimer/CTPA if PE suspected, sleep study if OSA suspected, alcohol history ("holiday heart")
CHA₂DS₂-VASc score should be calculated at diagnosis and documented -it determines anticoagulation need. See Management tab.
💊 Medications
Key Medication Classes -Atrial Fibrillation
Full drug tables with dosing, indications, and contraindications are in the Management tab (Rate Control, Rhythm Control, and Anticoagulation sections).
Category
First-Line
Key Pearl
Rate control
Metoprolol (Lopressor) (HFrEF) or Diltiazem (Cardizem) (preserved EF)
Diltiazem contraindicated if EF < 40%. Target HR < 110 at rest RACE II, 2010.
Rhythm control
Flecainide (Tambocor) (no structural disease) or Amiodarone (Cordarone) (HFrEF)
Flecainide is proarrhythmic in CAD/HFrEF. Amiodarone has cumulative organ toxicity.
Anticoagulation
Apixaban (Eliquis) 5 mg BIDPREFERRED
Lowest bleeding risk among DOACs ARISTOTLE, 2011. Warfarin only for valvular AF (mechanical valve, MS).
Acute RVR
Diltiazem (Cardizem) 20 mg IV bolus → drip 5–15 mg/hr
Fastest onset. Can repeat bolus q15 min. Transition to PO within 24h.
⚡ Summary
Summary
Three Pillars
Rate control, rhythm control where appropriate, and stroke prevention.Anticoagulation is decided independently of whether you choose rate or rhythm control, which is the single most misunderstood point: restoring sinus rhythm does not remove the stroke risk or the indication to anticoagulate.
Unstable Means Cardiovert Now
Hypotension, ischemic chest pain, acute heart failure or altered mental status → synchronized cardioversion immediately. Do not spend time on rate-control drugs. Ask whether the AF is actually causing the instability, since AF with RVR is frequently the consequence of sepsis, pulmonary embolism or hemorrhage rather than the cause, and cardioverting those patients achieves nothing.
Anticoagulate by CHA2DS2-VASc
Anticoagulate at a score of 2 or more in men and 3 or more in women; consider it at 1 and 2 respectively.DOACs are preferred over warfarin for almost everyone, with warfarin required in mechanical valves and moderate-to-severe mitral stenosis. HAS-BLED identifies modifiable bleeding risk; it is not a reason to withhold anticoagulation.
Rate Control by Ejection Fraction
Preserved EF: a beta blocker or diltiazem or verapamil.Reduced EF: a beta blocker, or amiodarone or digoxin; avoid non-dihydropyridine calcium channel blockers, whose negative inotropy precipitates decompensation. Target a resting rate below about 110 in the asymptomatic patient (RACE II showed lenient control is non-inferior), tightening only if symptoms or tachycardia-mediated cardiomyopathy demand it.
Never Give AV Nodal Blockers in Pre-Excited AF
An irregular wide-complex tachycardia in WPW.Adenosine, diltiazem, verapamil, beta blockers and digoxin all block the AV node and push conduction down the accessory pathway, which can precipitate ventricular fibrillation.Use procainamide or cardioversion.
Rhythm Control Has Moved Earlier
EAST-AFNET 4 showed early rhythm control within a year of diagnosis reduces cardiovascular outcomes.Favor it in younger patients, in symptomatic AF, in a first episode, and in heart failure, where ablation improves mortality and hospitalization in HFrEF (CASTLE-AF). Antiarrhythmic choice is structure-dependent: flecainide and propafenone only in structurally normal hearts, amiodarone or dofetilide otherwise.
Observe the Cardioversion Rules
AF lasting 48 h or more, or of unknown duration, needs 3 weeks of therapeutic anticoagulation beforehand or a TEE to exclude left atrial thrombus.Anticoagulate for at least 4 weeks after cardioversion regardless of rhythm, because atrial stunning means the thrombus risk persists after sinus rhythm returns.
Always Look for the Trigger and the Alternative
Sepsis, pulmonary embolism, thyrotoxicosis, alcohol, electrolyte derangement, ischemia, post-operative state and obstructive sleep apnea.Check a TSH in every new AF.Treat obesity, hypertension, alcohol intake and sleep apnea as part of the rhythm strategy, since risk-factor modification reduces AF burden as much as some drugs. Left atrial appendage occlusion for patients with a genuine long-term contraindication to anticoagulation.
📋 On Rounds
Pimp Questions
Why can't you give diltiazem in Afib with WPW?
CCBs and beta-blockers slow AV nodal conduction. In WPW, an accessory pathway (Bundle of Kent) bypasses the AV node. Blocking the AV node forces all conduction down the accessory pathway → extremely rapid ventricular rates → ventricular fibrillation → cardiac arrest. Use procainamide or synchronized cardioversion instead.
What CHA₂DS₂-VASc score triggers anticoagulation?
≥ 2 in males, ≥ 3 in females → anticoagulate (DOACs preferred). Score of 1 (male) or 2 (female) → consider anticoagulation. Score 0 (male) or 1 (female, sex point only) → no anticoagulation. Female sex alone doesn't warrant treatment -it's a modifier.
When must you use warfarin instead of a DOAC?
Valvular AF: mechanical heart valve or moderate-severe mitral stenosis. RE-ALIGN, 2013 showed dabigatran was harmful in mechanical valves -increased stroke and bleeding vs warfarin. Also consider warfarin if severe renal failure (CrCl < 15), antiphospholipid syndrome, or patient preference/cost.
What is the most commonly missed cause of refractory Afib with RVR?
Hypomagnesemia. Always check and replete Mg²⁺ > 2.0. Low magnesium destabilizes cardiac membrane potentials and makes rate control drugs less effective. IV magnesium 2g over 15 min can help convert or slow AF even before other agents kick in.
What did EAST-AFNET 4 show about rhythm control?
EAST-AFNET 4, 2020: early rhythm control (within 1 year of AF diagnosis) reduced a composite of cardiovascular death, stroke, and HF hospitalization compared to rate control alone. This shifted practice toward more aggressive early rhythm control, especially in patients with recent-onset AF and cardiovascular comorbidities.
Clinical Examples
📋 Case 1, New AF with RVR in HFpEF
Patient: 74 y/o F with HTN, DM2, HFpEF (EF 55%), presents with palpitations and dyspnea. HR 148, irregularly irregular.
Teaching point: Always replete Mg and K⁺ before concluding rate control is failing. Hypomagnesemia is the most commonly missed cause of refractory AF with RVR.
📋 Case 2, AF with RVR in HFrEF
Patient: 66 y/o M with HFrEF (EF 30%), worsening dyspnea, HR 140. Known paroxysmal AF, non-compliant with metoprolol.
Key findings: BP 98/62, JVP elevated, bibasilar crackles. BNP 4,200. Echo: EF 28%.
Management:
IV amiodarone 150 mg over 10 min then drip (CCBs contraindicated in HFrEF)
Restart metoprolol succinate once rate controlled
IV furosemide for congestion (warm and wet)
Consider early rhythm control EAST-AFNET 4, 2020
Teaching point: Diltiazem and verapamil are contraindicated in HFrEF, negative inotropes that worsen heart failure. Use amiodarone or digoxin for rate control.
📋 Case 3, AF with WPW (Pre-excitation)
Patient: 28 y/o M with palpitations and near-syncope. HR 210, irregular wide-complex tachycardia. Known WPW.
Key findings: BP 86/54, ECG: irregularly irregular wide-complex tachycardia with delta waves and varying QRS morphology.
Management:
DO NOT give AV nodal blockers (diltiazem, beta-blockers, digoxin, adenosine), risk of VF
If stable: IV procainamide (slows accessory pathway conduction)
Refer for EP study and catheter ablation of accessory pathway
Teaching point: In AF with WPW, AV nodal blockers force conduction through the accessory pathway → VF → cardiac arrest. Procainamide or cardioversion are the only safe options.
Sample Presentation
📋 Afib with RVR
"Mrs. Johnson is a 72-year-old woman with HTN, DM, and HFpEF (EF 55%) who presented with palpitations and HR 148, found to be in new-onset atrial fibrillation with RVR. She was hemodynamically stable. TSH was normal. K⁺ 3.6, Mg 1.4 -both repleted. She received diltiazem 20 mg IV bolus × 2 then started on a diltiazem drip at 10 mg/hr with rate down to 92. She was transitioned to diltiazem ER 180 mg daily. Her CHA₂DS₂-VASc is 4 (HTN, DM, age 65–74, female) -we started apixaban 5 mg BID for stroke prophylaxis. Echo showed no structural abnormality. Plan to reassess for rhythm control as outpatient."
RoundsRx Infographic Series · #6 · Cardiovascular · PDF 153 KB
Rotation
ICU / Critical Care
Ventilator management, hemodynamic support, end-organ protection, and rapid recognition of life-threatening conditions. These are the topics you will use every day.
End-stage liver disease with portal hypertension. Ascites is the most common complication -present in ~60% within 10 years. Every new ascites or admission needs a diagnostic paracentesis. Always tap -it changes management more than you expect.
🔍 Overview
Child-Pugh Classification
Parameter
1 Point
2 Points
3 Points
Bilirubin
< 2
2–3
> 3
Albumin
> 3.5
2.8–3.5
< 2.8
INR
< 1.7
1.7–2.3
> 2.3
Ascites
None
Mild (controlled)
Moderate-severe (refractory)
Encephalopathy
None
Grade I–II
Grade III–IV
A (5–6): 1-yr survival ~100%. B (7–9): ~80%. C (10–15): ~45%. Child-Pugh C = decompensated → transplant evaluation.
Used for transplant listing priority. Higher MELD = sicker = higher priority on the waitlist.
MELD ≥ 15: transplant generally beneficial over medical management
MELD ≥ 30: 3-month mortality > 50% without transplant
Decompensation Events
Development of any of these marks the transition from compensated to decompensated cirrhosis -median survival drops from > 12 years to ~2 years. Triggers transplant evaluation.
Hepatorenal syndrome (HRS) -functional renal failure from splanchnic vasodilation
Jaundice (bilirubin > 3 with liver failure)
💧 Ascites Management
Diagnostic Paracentesis -Always Tap
Every new-onset ascites, every admission, and every clinical deterioration in a cirrhotics requires diagnostic paracentesis. SBP is present in ~15% of cirrhotics admitted to hospital -often asymptomatic. You will miss it without tapping.
Send
Why
Cell count + differential
PMN ≥ 250/mm³ = SBP (treat immediately -don't wait for culture). This is the most important test.
Ascites protein < 1.5 g/dL = high risk for SBP → consider prophylaxis.
Culture (blood culture bottles at bedside)
Inoculate aerobic + anaerobic blood culture bottles with 10 mL each. Bedside inoculation ↑ yield from ~50% to ~80%.
Glucose, LDH, gram stain
If concerned for secondary peritonitis (perforation): glucose < 50, LDH > serum, polymicrobial → CT + surgery.
INR is NOT a contraindication to paracentesis. Cirrhotics are auto-anticoagulated but also auto-procoagulant (rebalanced hemostasis). Bleeding complications are < 1% even with INR > 2 and platelets < 50K. Do NOT transfuse FFP or platelets before a paracentesis.
Ascites Treatment
Step 1 -Sodium restriction
2g Na/day (< 88 mEq/day). This alone controls ascites in ~10–15%. Fluid restriction only if Na < 125 (dilutional hyponatremia).
Step 2 -Diuretics
Spironolactone 100 mg + furosemide 40 mg daily (100:40 ratio maintains K⁺ balance) AASLD Guidelines, 2021. Titrate every 3–5 days. Max: spironolactone 400 mg + furosemide 160 mg. Monitor weight (target loss 0.5 kg/day without edema, 1 kg/day with edema), BMP, Cr.
Step 3 -Large volume paracentesis (LVP)
If tense ascites or diuretic-refractory. Remove 5–8+ liters per session. If removing > 5 L → give albumin 6–8 g per liter removed (prevents post-paracentesis circulatory dysfunction) Ginès, 1988.
Step 4 -Refractory ascites
TIPS (transjugular intrahepatic portosystemic shunt) -reduces portal pressure, resolves ascites in ~75% Salerno, 2007. Risk: hepatic encephalopathy (30–50%). Contraindicated if: Child-Pugh > 13, MELD > 18 (relative), active HE, right heart failure. Or serial LVP q2 weeks + albumin.
⚠️ Key Complications
Hepatorenal Syndrome (HRS)
Functional renal failure -kidneys are structurally normal but underperfused due to splanchnic vasodilation + renal vasoconstriction
HRS-AKI (Type 1): rapid Cr rise > 2× baseline in < 2 weeks. Median survival 2 weeks without treatment.
Diagnosis: no response to volume challenge (albumin 1 g/kg × 2 days), no shock, no nephrotoxins, no parenchymal disease on UA/imaging
Treatment:Albumin 20–40 g/day + octreotide 200 mcg SC TID + midodrine 7.5–15 mg TID (splanchnic vasoconstrictors). Or norepinephrine drip in ICU (more effective). Definitive treatment: liver transplant.CONFIRM, 2021: terlipressin FDA-approved for HRS-AKI (improved renal function in ~30%).
Variceal Prophylaxis
Setting
Management
No varices
EGD screening. Repeat in 2–3 years (compensated) or 1 year (decompensated).
Small varices, no red signs
NSBB (propranolol 20–40 mg BID or nadolol 20–40 mg daily or carvedilol 6.25–12.5 mg dailyBañares, 2002). Target HR reduction 25% or HR 55–60.
Medium/large varices
NSBB (carvedilol preferred) OR endoscopic variceal ligation (EVL). Both are first-line for primary prophylaxis. PREDESCI, 2019: NSBB in compensated cirrhosis with CSPH delayed decompensation.
Post-bleed (secondary prophylaxis)
NSBB + EVL (combination is superior to either alone) Lo, 2012. TIPS if rebleeding despite combo Early-TIPS, 2010.
🧪 Workup
Workup
CBC, BMP, LFTs, INR, albumin
MELD-Na
RUQ US + AFP q6mo -HCC screening
EGD -variceal screening
Paracentesis -new ascites or clinical change
Hepatitis serologies
Autoimmune/metabolic panel
🚨 Management
Management
Ascites: Na restrict 2g/day + spiro/furosemide 100:40. LVP+albumin. TIPS if refractory.
Removing > 5 L of ascites causes post-paracentesis circulatory dysfunction (PPCD) -the rapid reduction in intra-abdominal pressure causes splanchnic vasodilation → effective hypovolemia → RAAS activation → sodium retention → faster ascites recurrence → HRS. Ginès, 1988 showed that albumin 6–8 g per liter removed prevents PPCD by expanding the intravascular volume. No other volume expander (NS, dextran, gelatin)
Why is INR NOT a contraindication to paracentesis in cirrhosis?
Cirrhotic coagulopathy is a rebalanced hemostasis -both procoagulant factors (II, VII, IX, X) AND anticoagulant factors (protein C, protein S, antithrombin) are reduced proportionally. The INR measures only the procoagulant side and overestimates bleeding risk. Multiple large studies show bleeding complications from paracentesis are < 1% even with INR > 2 and platelets < 50K.
What is the management of refractory ascites, and when do you consider TIPS?
Refractory ascites = doesn't respond to max diuretics (spironolactone 400 + furosemide 160) or diuretic-induced complications prevent dose escalation. Options: (1) Serial large-volume paracentesis (LVP) every 2-4 weeks + albumin infusion (6-8g per liter if > 5L drained). (2) TIPS (transjugular intrahepatic portosystemic shunt): reduces portal pressure → ascites resolves in ~75%.
What HCC screening do you order and how often?
Ultrasound + AFP (alpha-fetoprotein) every 6 months in all cirrhotic patients regardless of etiology. This is one of the most commonly missed screening protocols. If US is limited (obesity, nodular liver) → consider CT or MRI. If a lesion is found: LI-RADS classification on contrast-enhanced CT or MRI. LI-RADS 5 = definite HCC (arterial enhancement + washout on portal/delayed phase).
Clinical Examples
📋 Case 1, Tense Ascites with SBP
Patient: 58 y/o M with alcohol-related cirrhosis (Child-Pugh C, MELD-Na 22), presents with abdominal distension, fever 38.4°C, and diffuse abdominal pain.
Ceftriaxone 2g IV daily for SBP (PMN ≥ 250 = treat, do not wait for cultures)
IV albumin 1.5 g/kg on day 1, 1 g/kg on day 3 Sort, 1999
Therapeutic LVP + albumin 6-8g/L if > 5L removed Gines, 1988
Lifelong SBP prophylaxis after resolution: norfloxacin or TMP-SMX
Teaching point: Any cirrhotic with fever, abdominal pain, or encephalopathy needs diagnostic paracentesis before antibiotics. PMN ≥ 250 = SBP regardless of culture result.
📋 Case 2, Acute Variceal Hemorrhage
Patient: 62 y/o M with HCV cirrhosis, large-volume hematemesis. Known varices, not on beta-blocker prophylaxis.
EGD within 12h for band ligation; nadolol for secondary prophylaxis
Teaching point: Do NOT correct INR with FFP, cirrhotic coagulopathy is rebalanced. FFP adds volume and worsens portal hypertension. Paracentesis is safe even with elevated INR.
📋 Case 3, Hepatorenal Syndrome
Patient: 55 y/o F with NASH cirrhosis, MELD-Na 28, Cr rising 1.2 → 3.8 over 5 days despite albumin challenge.
Key findings: UNa < 10, bland sediment, renal US normal. Albumin 1.5 g/kg x2 days with no Cr improvement. FENa 0.2%.
Management:
HRS type 1 (rapid Cr rise, no response to albumin volume challenge)
Midodrine 7.5 mg TID + octreotide 100 mcg TID + albumin 25-50g daily
If refractory: norepinephrine drip (ICU) or terlipressin CONFIRM, 2021
Transplant evaluation, definitive treatment (> 80% mortality without transplant)
Teaching point: HRS is a diagnosis of exclusion. The albumin challenge (1.5 g/kg x2 days) is both diagnostic and therapeutic. Avoid NSAIDs, aminoglycosides, and ACEi/ARBs in all cirrhotics.
📣 Sample Presentation
One-Liner
"Mr. Nguyen is a 56-year-old with alcohol-related cirrhosis, Child-Pugh C, MELD-Na 24, presenting with tense ascites and bilateral lower extremity edema. No fever, no confusion."
Key Points to Cover on Rounds
Chronic decompensated cirrhosis. Paracentesis: 4L drained, albumin 25g IV infused (replace 6-8g per liter if >5L). Fluid: PMN 120 (no SBP), culture sent. Diuretics: spironolactone 100 mg + furosemide 40 mg (100:40 ratio). Na-restricted diet (2g/day). Varices: on nadolol for secondary prophylaxis. HCC screening: US + AFP done last month -negative. Hepatology following. Transplant evaluation in progress -6 months sobriety confirmed. MELD-Na 24.
Monitoring Parameters
Parameter
Frequency
Target / Action
Repeat paracentesis
At 48 hours
PMN should drop > 25% from baseline. If not improving → suspect resistant organism, secondary peritonitis, or wrong diagnosis. Broaden antibiotics and get CT abdomen.
BMP / Creatinine
Daily
HRS surveillance. Rising Cr despite albumin = hepatorenal syndrome → urgent nephrology + hepatology consult. Cr is the most important lab to trend.
Urine output
Strict I&Os
UOP < 0.5 mL/kg/hr or declining → early sign of HRS. Correlate with Cr trend.
Mental status
q4–8h
HE surveillance -SBP is the most common precipitant of hepatic encephalopathy. Worsening confusion → start/escalate lactulose.
Blood cultures
At diagnosis, repeat if persistent fever
Guide antibiotic narrowing once sensitivity data available.
The 48-hour paracentesis is critical. If PMN count is not dropping > 25%, you need to reconsider: resistant organism (broaden coverage), secondary peritonitis (get CT), or bacterascites that resolved on its own.
⚡ Summary
Summary
Always Tap
Every new-onset ascites, every admission, and every clinical deterioration in a cirrhotic needs a diagnostic paracentesis.SBP is present in about 15% of cirrhotics admitted to hospital and is frequently asymptomatic, with no fever and no abdominal pain. You will miss it without tapping, and the mortality of missed SBP is high.
The INR Is Not a Contraindication
Cirrhotics are simultaneously auto-anticoagulated and auto-procoagulant; hemostasis is rebalanced, not simply impaired.Bleeding complications are under 1% even with an INR above 2 and platelets below 50,000.Do not transfuse plasma or platelets to correct numbers before a tap: it delays the diagnosis and does not reduce the (already minimal) risk.
Read the Fluid Properly
SAAG at or above 1.1 g/dL means portal hypertension; below 1.1 means something else (peritoneal carcinomatosis, tuberculosis, pancreatic ascites). PMN above 250/mm³ means SBP, treat regardless of symptoms, with a third-generation cephalosporin plus albumin (1.5 g/kg day 1, 1 g/kg day 3), which reduces hepatorenal syndrome and mortality. Send fluid for culture in blood culture bottles at the bedside, which markedly raises the yield. Multiple organisms or a high protein with low glucose suggests secondary peritonitis, which needs imaging and surgery, not just antibiotics.
Repeat the Tap at 48 Hours
The PMN count should fall by more than 25%.If it has not, reconsider: a resistant organism needing broader coverage, secondary peritonitis needing a CT, or bacterascites that has resolved on its own. This single repeat study catches the treatment failures that otherwise present as deterioration days later.
Treat Ascites With Salt and Diuretics
Sodium restriction to about 2 g/day plus spironolactone and furosemide in a 100:40 ratio, which keeps potassium stable. Fluid restriction only for a sodium below 125.Large-volume paracentesis for tense ascites, with albumin 8 g per liter removed above 5 liters to prevent post-paracentesis circulatory dysfunction. Stop NSAIDs entirely, since they cause diuretic resistance and renal failure.
Prevent Variceal Bleeding Deliberately
Screening endoscopy at diagnosis.Non-selective beta blocker (propranolol, nadolol or carvedilol) or band ligation for medium to large varices, titrating the beta blocker to heart rate rather than blood pressure. Hold beta blockers in refractory ascites, SBP and hepatorenal syndrome, where the loss of cardiac output reserve worsens renal perfusion. Acute bleeding: octreotide, antibiotic prophylaxis with ceftriaxone (which improves survival independently), and endoscopy within 12 h.
Stage It and Watch for Decompensation
Child-Pugh and MELD both stage severity; MELD drives transplant listing.The decompensation events are ascites, variceal bleeding, hepatic encephalopathy and jaundice, and the first of them marks a sharp fall in survival. Refer for transplant evaluation at first decompensation, not when the patient is moribund.
Do Not Forget the Surveillance and the Vaccines
Hepatocellular carcinoma screening with ultrasound every 6 months, with or without AFP: it is the surveillance that most often lapses and the one that finds curable disease. Vaccinate against hepatitis A and B, influenza and pneumococcus.Treat the cause, alcohol cessation, hepatitis C, weight loss in MASLD, since removing the driver can reverse decompensation. Nutrition matters: these patients are sarcopenic, need 1.2 to 1.5 g/kg/day of protein and a late evening snack, and should never be protein-restricted.
💊 Medications
Key Medications -Cirrhosis & Portal Hypertension
Drug
Dose
Indication
Watch for
Lactulose 1ST LINE HE
30 mL PO TID, titrated
Hepatic encephalopathy. Acidifies the colon so ammonia is trapped as ammonium and purged.
Titrate to 2 to 3 soft stools per day, not to a fixed dose. Overshooting causes dehydration and hypernatremia, which themselves precipitate encephalopathy.
Rifaximin
550 mg PO BID
Added after a second episode of overt HE to prevent recurrence.
Minimal systemic absorption and well tolerated; cost is the main barrier. Used with lactulose, not instead of it.
Carvedilol (or propranolol, nadolol)
Carvedilol 6.25 mg daily, titrated
Non-selective beta-blockade for varices, primary and secondary prophylaxis. Carvedilol is generally preferred as it lowers portal pressure more.
Hold if systolic BP is below 90, in AKI, or in refractory ascites with hypotension, where NSBBs impair the compensatory response and worsen outcomes.
Spironolactone + furosemide
100 mg : 40 mg, ratio maintained on uptitration
Ascites. Spironolactone is the backbone because the ascites is aldosterone-driven.
The ratio preserves potassium balance. Watch Na, K and creatinine. Stop diuretics in AKI, hyponatremia below 120, or encephalopathy.
Albumin 25%
6 to 8 g per liter removed; 1.5 g/kg then 1 g/kg in SBP
After large-volume paracentesis over 5 L, in SBP, and as part of HRS treatment.
Prevents post-paracentesis circulatory dysfunction, and in SBP reduces renal failure and mortality. Give on day 1 and day 3 in SBP.
Ceftriaxone / cefotaxime
Ceftriaxone 1 to 2 g IV daily
SBP treatment, and short-course prophylaxis during variceal bleeding.
Diagnose SBP on an ascitic PMN count of 250 or more. Treat before the culture returns; cultures are negative in a substantial minority.
Octreotide
50 mcg IV bolus, then 50 mcg/hr
Acute variceal bleeding, alongside antibiotics and endoscopy.
Splanchnic vasoconstriction reduces portal inflow. Continue for 3 to 5 days after control.
Terlipressin or midodrine + octreotide
With albumin in both cases
Hepatorenal syndrome (HRS-AKI). Terlipressin where available, otherwise midodrine plus octreotide.
Terlipressin carries a real risk of ischemic and respiratory complications; select patients carefully and monitor oxygenation.
Drugs to avoid or dose with care in cirrhosis:NSAIDs (precipitate AKI and blunt diuretic response), aminoglycosides, and sedatives including benzodiazepines which both mask and worsen encephalopathy. Acetaminophen is acceptable at up to 2 g/day and is preferred over NSAIDs for analgesia.
Ascitic fluid infection in cirrhosis. PMN ≥ 250/mm³ = SBP. Start antibiotics immediately -do not wait for cultures. Albumin on day 1 and day 3 prevents hepatorenal syndrome.
🚨 Management
Diagnostic Criteria
Ascitic fluid PMN ≥ 250 cells/mm³ = SBP. Start antibiotics immediately. Do NOT wait for culture results.
PMN ≥ 250/mm³ with positive culture = SBP
PMN ≥ 250/mm³ with negative culture = culture-negative neutrocytic ascites (CNNA) -treat the same as SBP
PMN < 250/mm³ with positive culture = bacterascites -repeat paracentesis in 48h. Treat if symptomatic or PMN rises.
Polymicrobial (multiple organisms including anaerobes)
Glucose
> 50 mg/dL
< 50 mg/dL
LDH
< serum LDH
> serum LDH
Protein
Low (< 1 g/dL)
Higher
Treatment
Antibiotics alone
Antibiotics + surgical source control (CT abdomen → OR)
Runyon's criteria for secondary peritonitis: if ascitic fluid shows ≥ 2 of (glucose < 50, LDH > ULN serum, protein > 1 g/dL) + polymicrobial gram stain → get CT abdomen to rule out perforation. This patient needs surgery, not just antibiotics.
Common Organisms
E. coli (~40%) -most common
Klebsiella pneumoniae (~10–15%)
Streptococcus pneumoniae (~10%)
Enterococcus (~5–10%)
Mechanism: bacterial translocation from gut lumen → mesenteric lymph nodes → bloodstream → ascitic fluid (which has impaired opsonization due to low complement/protein)
Treatment
Component
Regimen
Notes
Antibiotics IMMEDIATE
Ceftriaxone 2g IV daily × 5 days
Covers E. coli, Klebsiella, strep. If nosocomial SBP or recent FQ prophylaxis failure → broaden to piperacillin-tazobactam or meropenem (resistance is higher). Narrow based on culture + sensitivity.
Albumin CRITICAL
1.5 g/kg on day 1, then 1 g/kg on day 3
SBP Albumin Trial, 1999: albumin with antibiotics in SBP reduced HRS from 33% to 10% and mortality from 29% to 10%. One of the most impactful interventions in hepatology. Do not skip this.
Follow-Up & Response
Repeat paracentesis at 48h if no clinical improvement. PMN should decrease by ≥ 25%. If not → suspect resistant organism, secondary peritonitis, or wrong diagnosis.
Total duration: 5 days if culture-guided. 5–7 days empiric if culture-negative.
After first SBP episode → lifelong prophylaxis (see below)
Transplant evaluation -1-year survival after SBP is ~30–70%. SBP marks a critical inflection point.
Ascitic protein < 1.5 g/dL + advanced liver disease (Child-Pugh ≥ 9 with bilirubin ≥ 3 OR Cr ≥ 1.2 or Na ≤ 130 or BUN ≥ 25)
Norfloxacin 400 mg daily (or alternatives as above). Fernández, 2007: primary prophylaxis in high-risk patients reduced SBP incidence and improved survival.
Acute GI hemorrhage (all cirrhotics)
Ceftriaxone 1g IV daily × 7 days -reduces SBP, bacteremia, and mortality in acute variceal bleed Fernández, 2006.
🔄 Updated Practice: Old teaching: all cirrhotic patients with ascites need fluoroquinolone prophylaxis for SBP. Current practice: SBP prophylaxis is only recommended for (1) prior SBP episode (secondary prophylaxis -norfloxacin or TMP-SMX), (2) GI bleed in cirrhosis (ceftriaxone 1g IV × 7 days), or (3) ascitic fluid protein <1.5 g/dL with either Child-Pugh ≥9 or renal dysfunction. Indiscriminate FQ use drives resistance. Also: rifaximin (Xifaxan) may be an alternative for SBP prophylaxis -emerging evidence but not yet guideline-recommended.
📋 On Rounds
Why is albumin so important in SBP treatment?
SBP Albumin Trial, 1999: in the landmark RCT, adding albumin (1.5 g/kg day 1, 1 g/kg day 3) to ceftriaxone in SBP reduced renal impairment (HRS) from 33% to 10% and in-hospital mortality from 29% to 10%. The mechanism: SBP causes an inflammatory cascade → splanchnic vasodilation → effective hypovolemia → RAAS activation → renal vasoconstriction → HRS.
Why do you give albumin with antibiotics in SBP, and what's the dosing?
Albumin prevents hepatorenal syndrome (HRS), which is the leading cause of death in SBP -not the infection itself. The Sort trial SBP Albumin Trial, 1999 showed albumin 1.5 g/kg on day 1 + 1 g/kg on day 3 reduced renal failure from 33% to 10% and mortality from 29% to 10%. The mechanism: SBP causes massive cytokine release → splanchnic vasodilation → effective hypovolemia → renal hypoperfusion.
What are the criteria for SBP prophylaxis and what do you prescribe?
Primary prophylaxis (never had SBP): indicated if ascitic fluid protein < 1.5 g/dL + either (1) renal dysfunction (Cr > 1.2, BUN > 25, or Na < 130) or (2) liver failure (Child-Pugh ≥ 9 + bilirubin ≥ 3). Drug: norfloxacin 400 mg daily or TMP-SMX DS daily. Secondary prophylaxis (after first SBP episode): LIFELONG -norfloxacin 400 mg daily or TMP-SMX DS daily. Recurrence rate without prophylaxis is ~70% at 1 year.
Why is ceftriaxone preferred over fluoroquinolones for SBP treatment?
Rising fluoroquinolone resistance (many cirrhotic patients are on norfloxacin/cipro prophylaxis → resistant organisms). Ceftriaxone 2g IV daily has excellent activity against the common SBP pathogens (E. coli, Klebsiella, Strep) and is well-tolerated in liver disease. If the patient develops SBP while already on FQ prophylaxis, the organism is likely FQ-resistant → ceftriaxone or pip-tazo.
Clinical Examples
📋 Case 1, Classic SBP with Albumin Protocol
Patient: 56M with alcoholic cirrhosis (Child-Pugh C), large-volume ascites. Presents with fever 38.9°C, diffuse abdominal tenderness, worsening hepatic encephalopathy.
Ceftriaxone 2g IV daily × 5 days, start immediately once PMN ≥ 250
Albumin 1.5 g/kg on day 1 + 1 g/kg on day 3 SBP Albumin Trial, 1999
Repeat paracentesis at 48h, PMN should drop > 25%
Start norfloxacin 400 mg PO daily at discharge (lifelong secondary prophylaxis)
Teaching point: Albumin reduces HRS from 33% to 10% and mortality from 29% to 10%. This is one of the highest-impact interventions in hepatology, never skip the albumin.
📋 Case 2, Nosocomial SBP on FQ Prophylaxis
Patient: 63F with NASH cirrhosis, admitted for variceal bleed 5 days ago. On norfloxacin prophylaxis. New fever 38.4°C, increasing abdominal distension.
Key findings: Paracentesis: PMN 380. Gram stain: GPC in clusters. Already on FQ prophylaxis, likely resistant organism.
Management:
Piperacillin-tazobactam 4.5g IV q8h (broader coverage for nosocomial SBP)
Albumin protocol: 1.5 g/kg day 1, 1 g/kg day 3
If gram-positive organism confirmed, consider vancomycin
Repeat paracentesis at 48h to confirm response
Teaching point: Nosocomial SBP and SBP in patients on FQ prophylaxis have higher rates of resistant organisms (including MRSA and ESBL). Broaden empiric coverage to piperacillin-tazobactam or meropenem.
📋 Case 3, SBP vs Secondary Bacterial Peritonitis
Patient: 48M with cirrhosis, abdominal pain, fever. Paracentesis: PMN 1200, glucose 28 mg/dL, LDH 450 (above serum ULN), total protein 2.8 g/dL. Gram stain shows polymicrobial organisms.
Key findings: Runyon criteria for secondary peritonitis met: glucose < 50, LDH > ULN, protein > 1 g/dL, polymicrobial. This is NOT SBP, suspect bowel perforation.
Management:
Urgent CT abdomen with contrast to identify source (perforation, abscess)
Teaching point: Always check ascitic fluid glucose, LDH, and protein to differentiate SBP from secondary peritonitis. Polymicrobial gram stain, glucose < 50, LDH > ULN, and protein > 1 g/dL suggest secondary peritonitis requiring CT and surgical evaluation.
📣 Sample Presentation
One-Liner
"Mr. DeSilva is a 52-year-old with cirrhosis and ascites presenting with fever 38.6°C, diffuse abdominal pain, and worsening confusion. Paracentesis: PMN 680. Consistent with SBP."
Key Points to Cover on Rounds
PMN 680 (>250 = SBP). Gram stain: GNR (likely E. coli). Culture pending. Antibiotics: ceftriaxone 2g IV daily started within 1 hour. Albumin protocol: 1.5 g/kg (112g) on day 1, 1 g/kg (75g) on day 3 to prevent HRS SBP Albumin Trial, 1999. Repeat paracentesis at 48h planned (PMN should drop >25%). Mental status improving with lactulose (SBP was the precipitant for HE). Plan: 5-day antibiotic course, start norfloxacin prophylaxis at discharge.
PMN should drop > 25% from baseline. If not improving → suspect resistant organism, secondary peritonitis, or wrong diagnosis. Broaden antibiotics and get CT abdomen.
BMP / Creatinine
Daily
HRS surveillance. Rising Cr despite albumin = hepatorenal syndrome → urgent nephrology + hepatology consult. Cr is the most important lab to trend.
Urine output
Strict I&Os
UOP < 0.5 mL/kg/hr or declining → early sign of HRS. Correlate with Cr trend.
Mental status
q4–8h
HE surveillance -SBP is the most common precipitant of hepatic encephalopathy. Worsening confusion → start/escalate lactulose.
Blood cultures
At diagnosis, repeat if persistent fever
Guide antibiotic narrowing once sensitivity data available.
The 48-hour paracentesis is critical. If PMN count is not dropping > 25%, you need to reconsider: resistant organism (broaden coverage), secondary peritonitis (get CT), or bacterascites that resolved on its own.
Diagnostic paracentesis is mandatory in any cirrhotic with ascites presenting with fever, abdominal pain, AMS, or worsening clinical status. Tap first, then start antibiotics.
Diagnostic paracentesis: Cell count with differential (PMN ≥ 250/mm³ = SBP), gram stain, culture (inoculate blood culture bottles at bedside), albumin, total protein
Covers E. coli, Klebsiella, Strep. Start immediately once PMN ≥ 250. If nosocomial SBP or FQ prophylaxis failure → broaden to piperacillin-tazobactam or meropenem.
Albumin CRITICAL
1.5 g/kg on day 1 + 1 g/kg on day 3
2 doses
Reduces HRS from 33% to 10% and mortality from 29% to 10% SBP Albumin Trial, 1999. Do NOT skip this -one of the highest-impact interventions in hepatology.
PROPHYLAXIS (after acute treatment)
Norfloxacin
400 mg PO daily
Lifelong (secondary prophylaxis)
First-line for secondary prophylaxis after first SBP episode. Also for primary prophylaxis if ascitic protein < 1.5 g/dL with renal/liver dysfunction.
TMP-SMX DS
1 DS tablet PO daily
Lifelong
Alternative to norfloxacin for secondary prophylaxis. Equally effective.
Ceftriaxone (Rocephin)
1g IV daily
7 days
Acute GI hemorrhage prophylaxis in all cirrhotics -reduces SBP, bacteremia, and mortality during variceal bleed.
Primary prophylaxis criteria: ascitic fluid protein < 1.5 g/dL PLUS either Child-Pugh ≥ 9 with bilirubin ≥ 3, OR renal dysfunction (Cr ≥ 1.2, Na ≤ 130, BUN ≥ 25).
⚡ Summary
Summary
The Diagnostic Number
Ascitic fluid PMN count of 250 cells/mm³ or more is SBP, regardless of culture.Start antibiotics immediately and do not wait for the culture, which is negative in a substantial proportion of true cases because the organism load in ascites is low. Send fluid in blood culture bottles at the bedside to improve the yield.
Tap Everyone Who Might Have It
Every new-onset ascites, every admission of a cirrhotic, and every clinical deterioration.SBP is frequently asymptomatic: no fever, no abdominal pain, no tenderness. New or worsening encephalopathy, a rising creatinine, or unexplained deterioration is often the only presentation.
The INR Is Not a Contraindication to the Tap
Bleeding complications are under 1% even with an INR above 2 and platelets below 50,000, because hemostasis in cirrhosis is rebalanced rather than simply impaired. Do not transfuse plasma or platelets before the procedure: it delays the diagnosis, raises portal pressure and does not lower the already minimal risk.
Cefotaxime or Ceftriaxone for 5 Days
A third-generation cephalosporin is first line and covers the usual organisms. E. coli, Klebsiella and Streptococcus pneumoniae predominate, and the infection is characteristically monomicrobial. Consider broader coverage in nosocomial or healthcare-associated cases, where resistant organisms are common.
Albumin Is Part of the Treatment, Not an Extra
1.5 g/kg on day 1 and 1 g/kg on day 3.It reduces hepatorenal syndrome and mortality, by supporting effective circulating volume in a patient whose splanchnic vasodilation is being worsened by the infection. Give it to those at highest risk: creatinine above 1 mg/dL, BUN above 30, or bilirubin above 4.
Repeat the Tap at 48 Hours
The PMN count should fall by more than 25%.If it has not, think resistant organism, or secondary peritonitis, and get imaging. This single repeat study is what separates a treatment failure from a patient who is simply slow to improve.
Distinguish Secondary Peritonitis
Suspect it with multiple organisms, or with two of: total protein above 1 g/dL, glucose below 50 mg/dL, LDH above the upper limit of normal in serum.Secondary peritonitis needs imaging and usually surgery, and treating a perforated viscus as SBP with antibiotics alone is fatal.
Set Up Prophylaxis and Referral Before Discharge
Secondary prophylaxis after an episode is lifelong, usually with daily norfloxacin or ciprofloxacin or TMP-SMX, since recurrence approaches 70% in the first year. Primary prophylaxis for ascitic protein below 1.5 g/dL with renal or hepatic dysfunction, and short-course ceftriaxone during a variceal bleed.Avoid non-selective beta blockers during an episode of SBP, where they worsen hemodynamics. Refer for transplant assessment: SBP marks a sharp fall in survival.
RoundsRx Infographic Series · #74 · Gastro & Hepatology · PDF 148 KB
Text version
GI / Hepatology · One Pager
Spontaneous Bacterial Peritonitis
PMN ≥ 250 on paracentesis. Ceftriaxone + albumin (1.5g/kg day 1 + 1g/kg day 3). Lifelong secondary prophylaxis. Start transplant eval.
🧪 Diagnosis
Ascitic fluid PMN ≥ 250/mm³. Do paracentesis in every cirrhotic with fever, AMS, abdominal pain, or clinical deterioration. Don't wait for culture.
🚨 Treatment
Ceftriaxone 2g IV daily × 5 days. Albumin 1.5g/kg day 1 + 1g/kg day 3 (prevents HRS) SBP Albumin Trial, 1999. Repeat paracentesis at 48h (PMN should drop > 25%).
💊 Prophylaxis
Secondary (after first SBP): norfloxacin 400 mg or TMP-SMX DS daily -LIFELONG. Primary: if ascitic protein < 1.5 + renal/liver dysfunction. GI bleed: ceftriaxone × 7 days.
💊 Key Drugs
Ceftriaxone2g IV daily × 5d
Albumin1.5g/kg D1 + 1g/kg D3
Norfloxacin400 mg daily (prophylaxis)
TMP-SMX DS1 tab daily (alternative)
⚠️ Pitfalls
Not doing paracentesis (the test IS the diagnosis)
Forgetting albumin (prevents HRS -mortality benefit)
The most common healthcare-associated infection. Antibiotics disrupt the normal gut flora → C. diff overgrowth → toxin production → colitis. Fidaxomicin is now first-line over oral vancomycin. Stop the offending antibiotic if possible.
🔍 Overview
Risk Factors
Antibiotics -#1 risk factor. Worst offenders: fluoroquinolones (#1), clindamycin, cephalosporins, carbapenems. But ANY antibiotic can cause it.
Age > 65
Hospitalization / healthcare facility
PPI use -controversial but associated in multiple studies
Immunosuppression, chemotherapy, IBD, recent GI surgery
Diagnosis
Only test patients with ≥ 3 unformed stools in 24h. Do NOT test formed stool. Do NOT test asymptomatic patients. Do NOT test as "test of cure" after treatment.
Best test: NAAT (PCR) for toxin gene -highly sensitive. But detects carriers too (can be positive for weeks after treatment). Combine with toxin EIA for clinical disease.
Fidaxomicin 200 mg PO BID × 10 days PREFERRED OR vancomycin 125 mg PO QID × 10 days
Fidaxomicin 200 mg PO BID × 10 days (preferred) or vancomycin pulse-taper
Vancomycin pulse-taper, fidaxomicin, or fecal microbiota transplant (FMT)
Severe
Vancomycin (Vancocin) 125 mg PO QID × 10 days OR fidaxomicin 200 mg PO BID × 10 days
Same as first episode + consider FMT
FMT strongly recommended
Fulminant
Vancomycin 500 mg PO/NG QID + metronidazole 500 mg IV q8h. If ileus: add vancomycin retention enemas 500 mg in 100 mL NS q6h. Surgical consult → subtotal colectomy if toxic megacolon, perforation, or no improvement.
Same approach. Early surgical involvement critical.
Key Treatment Principles
Stop the offending antibiotic if at all possible -this is the single most important step
Fidaxomicin is now preferred over vancomycin for initial non-severe CDI IDSA/SHEA, 2021 -lower recurrence rate (~13% vs ~27%) because it's narrow-spectrum and preserves normal flora
IV metronidazole is ONLY used in fulminant CDI (as adjunct to PO/PR vancomycin). It is NOT first-line for any other severity -oral metronidazole is inferior to vancomycin
Do NOT use loperamide (Imodium) -can precipitate toxic megacolon
Contact precautions: gown + gloves, hand washing with soap and water (alcohol-based sanitizer does NOT kill C. diff spores)
Bezlotoxumab (anti-toxin B monoclonal antibody): single IV dose during treatment → reduces recurrence by ~40% MODIFY I/II, 2017. Consider for high recurrence risk patients.
🔄 Updated Practice: Old teaching: oral metronidazole (Flagyl) is first-line for C. difficile. WRONG -this changed in 2017. Current first-line (IDSA/SHEA 2021): fidaxomicin (Dificid) 200mg BID × 10 days (preferred -lower recurrence) OR vancomycin 125mg PO QID × 10 days. Oral metronidazole is NO LONGER recommended for initial episodes. IV metronidazole is only added in fulminant C. difficile (when ileus may prevent oral drug delivery to the colon). Also: fecal microbiota transplant (FMT) is recommended after ≥2 recurrences.
Vancomycin Pulse-Taper (for recurrence)
🧪 Workup
Diagnostic Workup -C. difficile
Only test unformed stool in symptomatic patients (≥ 3 episodes/24h). Do NOT test formed stool. Do NOT test asymptomatic patients. Do NOT retest as "test of cure" after treatment.
Test
Rationale
Key Values / Notes
Stool C. diff testing
Confirm diagnosis. Use institutional algorithm -do NOT order both PCR and toxin independently.
NAAT/PCR = highly sensitive (detects carriers). Toxin EIA = specific for active disease. Best approach: GDH screen → toxin EIA, or NAAT + toxin EIA. PCR⁺/toxin⁻ = possible carrier -use clinical judgment.
CBC with differential
WBC stratifies severity and identifies fulminant disease.
WBC > 15K = severe. WBC > 30K = fulminant (high mortality). Bandemia and left shift common.
BMP (Cr)
Creatinine defines severity. Monitor renal function during illness.
Cr ≥ 1.5 mg/dL = severe (IDSA/SHEA criteria). Also check K⁺ (diarrheal losses) and bicarb.
Gradual taper allows spore germination between doses, then kills vegetative forms. Effective for breaking recurrence cycle.
Metronidazole (Flagyl)
500 mg IV q8h
IV
Fulminant CDI adjunct ONLY (with PO/PR vancomycin)
NO longer recommended as monotherapy for any severity. IV metronidazole reaches colon via biliary excretion -useful when ileus prevents oral drug delivery.
Vancomycin enemas
500 mg in 100 mL NS q6h
PR
Fulminant CDI with ileus (oral medications cannot reach colon)
Given in addition to PO/NG vancomycin and IV metronidazole. Retain for 60 minutes if possible.
Bezlotoxumab (Zinplava)
10 mg/kg IV × 1 dose
IV
Recurrence prevention in high-risk patients (during active treatment course)
Anti-toxin B monoclonal antibody. Reduces recurrence by ~40% MODIFY I/II, 2017. Consider if: age ≥ 65, immunocompromised, severe CDI, or prior recurrence.
Fecal microbiota transplant (FMT)
Per protocol (colonoscopic, capsule, or enema)
Various
After ≥ 2 recurrences despite appropriate antibiotic therapy
~85-90% cure rate for recurrent CDI. FDA-approved products now available (RBX2660/Rebyota, SER-109/Vowst). Restores normal gut microbiome.
📋 On Rounds
Why is fidaxomicin preferred over vancomycin now?
Fidaxomicin is a narrow-spectrum macrocyclic antibiotic that kills C. diff but preserves the normal anaerobic gut flora (Bacteroides and other protective commensals). Vancomycin kills C. diff but also disrupts normal flora -leaving the gut vulnerable to recolonization once vancomycin is stopped. This is why fidaxomicin has a significantly lower recurrence rate (~13% vs ~27%)Louie, 2011.
Why doesn't alcohol-based hand sanitizer work for C. diff?
C. difficile forms spores -a dormant, highly resistant form that survives on surfaces for months. Spores have a tough outer coat that is resistant to alcohol, heat, and most disinfectants. Alcohol-based hand sanitizers kill vegetative bacteria but cannot penetrate or destroy spores. Only mechanical removal with soap and water (friction + rinsing) and sporicidal agents (bleach-based disinfectants for surfaces) are effective.
When should you consult surgery for C. difficile?
Surgical consultation for fulminant C. diff: (1) Toxic megacolon (colon > 6 cm on imaging), (2) Bowel perforation, (3) Hemodynamic instability requiring vasopressors, (4) Organ failure (AKI, respiratory failure), (5) WBC > 30K or lactate > 5 (markers of severity associated with high mortality). Surgery = subtotal colectomy with end ileostomy. Mortality of fulminant C. diff requiring surgery is 30-50% even with intervention.
Why is fidaxomicin preferred over oral vancomycin for C. diff?
Fidaxomicin has a significantly lower recurrence rate (~13% vs ~27% for vancomycin). Mechanism: fidaxomicin is narrow-spectrum (kills C. diff but spares normal gut flora), while vancomycin is broader and disrupts the microbiome → easier for C. diff to re-establish. IDSA/SHEA, 2021 now recommends fidaxomicin as first-line for initial and recurrent episodes. The downside: cost (~$3,500 vs ~$200 for vancomycin).
Case 1: First Episode Non-Severe CDI
Presentation: 68F admitted for UTI on ceftriaxone × 3 days, now with 5 episodes of watery, non-bloody diarrhea over 24 hours. Afebrile, hemodynamically stable. Mild LLQ tenderness without peritoneal signs.
Discontinue ceftriaxone, switch to narrower-spectrum agent if UTI treatment still needed
Start fidaxomicin (Dificid) 200 mg PO BID × 10 daysPREFERRED, or vancomycin 125 mg PO QID × 10 daysIDSA/SHEA, 2021
Contact precautions: gown + gloves, dedicated equipment, hand washing with soap and water (not alcohol-based sanitizer, does not kill spores)
Avoid loperamide, risk of toxic megacolon
Monitor stool frequency and WBC, do NOT retest stool as "test of cure"
Key Teaching Point: Oral metronidazole is NO longer first-line for C. diff, this changed in 2017. Fidaxomicin has a lower recurrence rate (~13% vs ~27%) because it preserves normal anaerobic gut flora.
Case 2: Fulminant C. difficile with Toxic Megacolon
Presentation: 72M with recent hospitalization for pneumonia (completed levofloxacin course), re-admitted with profuse watery diarrhea × 3 days, now with abdominal distension, absent bowel sounds, fever 39.2°C, HR 118, BP 82/50 on 2L NS bolus.
Labs: WBC 28,000 with 15% bands, Cr 2.8 mg/dL (baseline 1.0), lactate 4.2 mmol/L, albumin 1.9. CT abdomen: diffuse colonic wall thickening with pericolonic stranding, transverse colon dilated to 7.5 cm, toxic megacolon.
Vancomycin 500 mg PO/NG QID + vancomycin 500 mg in 100 mL NS retention enema q6h (ileus, oral meds may not reach colon)
Metronidazole (Flagyl) 500 mg IV q8h, reaches colon via biliary excretion when ileus prevents oral delivery
Urgent surgical consult for subtotal colectomy, colon > 6 cm = megacolon, lactate > 5 associated with high mortality
ICU transfer for vasopressor support and close monitoring
Aggressive IV fluid resuscitation, correct electrolytes (K⁺, Mg²⁺ from diarrheal losses)
NPO status, NG tube if ileus, serial abdominal exams q4-6h for perforation signs
Surgical Emergency: Mortality of fulminant C. diff requiring colectomy is 30-50%. Delay in surgery worsens outcomes. If no clinical improvement in 24-48h on max medical therapy, proceed to OR.
Case 3: Second Recurrence, Treatment Failure
Presentation: 55F with third episode of C. diff in 6 months. First episode treated with vancomycin 125 mg PO QID × 10 days, recurred 3 weeks after completion. Second episode treated with vancomycin pulse-taper × 6 weeks, recurred again 2 weeks after stopping. Now with 6 watery stools/day, cramping, WBC 11,000, Cr 0.8. Stool toxin positive.
Classification: Non-severe, second recurrence (third episode overall). Standard antibiotic therapy has failed.
Management Options:
Fidaxomicin (Dificid) 200 mg PO BID × 10 days, if not yet tried, preferred over vancomycin for recurrence (narrow-spectrum, preserves gut flora)
Extended vancomycin pulse-taper: 125 mg QID × 14d → BID × 7d → daily × 7d → every 2 days × 7d → every 3 days × 14d
Bezlotoxumab (Zinplava) 10 mg/kg IV × 1 dose during antibiotic treatment, anti-toxin B monoclonal antibody, reduces recurrence by ~40% MODIFY I/II, 2017
ID consultation for complex recurrent CDI management
Recurrence Strategy: After 2+ recurrences, the goal shifts from killing C. diff to restoring the protective microbiome. FMT is the most effective option. Bezlotoxumab can be added to any antibiotic course to reduce recurrence risk in high-risk patients.
📣 Sample Presentation
One-Liner
"Mrs. Clark is a 72-year-old recently discharged after hip replacement (received cefazolin perioperatively) presenting with watery diarrhea 8×/day, WBC 18K, Cr 1.1. C. diff toxin positive."
Key Points to Cover on Rounds
Non-severe C. diff (WBC 18K but Cr 1.1). Treatment: fidaxomicin 200 mg BID × 10 days (preferred over vanc PO -lower recurrence rate IDSA/SHEA, 2021). Cefazolin was the precipitant -no current antibiotics to stop. Contact precautions. Soap and water hand hygiene (alcohol doesn't kill spores). Stool frequency tracking: 8/day → 4/day on day 2. Plan: complete 10-day course, consider bezlotoxumab if high recurrence risk (age >65, immunocompromised, prior C. diff).
Monitoring -C. difficile
Parameter
Frequency
Target / Action
Stool frequency
Daily (nursing stool count)
Expect improvement in 3-5 days. Stool frequency should decrease. Diarrhea may persist for days even with effective treatment -judge by trend, not single day.
WBC
Daily if severe or fulminant; q2-3 days if non-severe
Trending down = improving. Rising WBC (especially > 30K) = worsening → reassess severity, consider surgical consult. Leukemoid reaction (> 40K) is a poor prognostic sign.
Creatinine
Daily if severe/fulminant; at baseline and mid-course if non-severe
Rising Cr = worsening (may need to escalate therapy). AKI from volume depletion -ensure adequate hydration.
Aggressive IV fluid resuscitation for dehydration from diarrhea. Monitor UOP, orthostatics, mucous membranes.
Do NOT repeat C. diff testing for "test of cure." PCR can remain positive for weeks after successful treatment. Retesting leads to unnecessary retreatment. Judge resolution by clinical improvement (decreased stool frequency, resolving WBC/Cr), not by repeat testing.
⚡ Summary
Summary
Fidaxomicin Is Now First Line
Fidaxomicin 200 mg BID for 10 days is preferred over oral vancomycin (IDSA/SHEA 2021). Recurrence is about 13% versus 27%, because fidaxomicin is narrow-spectrum and spares the normal anaerobic flora that keeps C. difficile suppressed. Oral vancomycin 125 mg QID remains an acceptable alternative where cost or access is limiting.
Metronidazole Is No Longer First Line
This changed in 2017. Oral metronidazole is inferior for cure and recurrence, and it is now reserved for settings where neither preferred agent is available. The exception is fulminant disease, where IV metronidazole is added to oral vancomycin because the oral drug may not reach an ileus-obstructed colon.
Test Only Symptomatic Patients With Unformed Stool
Three or more unformed stools in 24 h.Do not test formed stool, do not test asymptomatic patients, and never send a test of cure: colonization is common and PCR stays positive for weeks after successful treatment. Testing the wrong patient produces a positive result that gets treated as disease, which is the commonest diagnostic error here.
Stop the Offending Antibiotic Wherever You Can
Continuing the precipitating antibiotic markedly reduces cure and raises recurrence. If antibacterial therapy is genuinely required, narrow it as far as possible. Also review proton pump inhibitors and stop those without a clear indication.
Grade the Severity, Because It Changes the Route
Non-severe: WBC below 15,000 and creatinine below 1.5 mg/dL. Severe: either threshold crossed. Fulminant: hypotension, shock, ileus or megacolon.Fulminant disease gets oral vancomycin 500 mg QID plus IV metronidazole, with vancomycin enemas if there is ileus, and urgent surgical consultation.
Do Not Give Antimotility Agents in Severe Disease
Loperamide and opioids slow transit and retain toxin, and they can precipitate toxic megacolon. Ileus in a C. difficile patient is an ominous sign, not an improvement: the diarrhea stopping while the patient gets sicker means the colon has stopped working.
Treat Recurrence Differently From the First Episode
First recurrence: fidaxomicin, or a vancomycin pulse-taper if vancomycin was used first.Second and subsequent recurrences: fecal microbiota transplantation, which is highly effective because it restores the flora rather than suppressing the organism. Bezlotoxumab, an anti-toxin B monoclonal antibody, can be added to reduce recurrence in high-risk patients (use cautiously in heart failure).
Infection Control Is Part of the Treatment
Contact precautions and a private room, and hand washing with soap and water, because alcohol gel does not kill C. difficile spores.Clean the room with a sporicidal agent. These measures protect the next patient, and forgetting them is how a single case becomes a ward outbreak.
Bleeding distal to the ligament of Treitz. Usually presents with hematochezia (bright red blood per rectum). 80–85% stop spontaneously. The key question: is this really a lower bleed, or is it a brisk upper GI bleed presenting with hematochezia?
🔍 Overview
Common Causes
Cause
% of LGIB
Key Features
Diverticular bleed
~30-40%
Most common cause in adults > 60. Painless, large-volume, bright red blood. Usually self-limited (80% stop spontaneously). Right-sided diverticula bleed more often than left. Recurrence ~20-35% at 1 year Niikura, 2015.
Hemorrhoids
~20%
Bright red blood on toilet paper or coating stool. Most common cause of LGIB overall when including outpatient. Usually minor.
Angiodysplasia / AVM
~10%
Vascular ectasias, usually right colon. Chronic, intermittent bleeding. Associated with aortic stenosis (Heyde syndrome) and CKD.
Occult or slow chronic bleeding → iron deficiency anemia. Mass on colonoscopy.
Post-polypectomy bleed
Variable
1–7 days after colonoscopy with polypectomy. Usually self-limited.
Rule out upper GI source first. Up to 15% of patients presenting with hematochezia have a brisk UPPER GI bleed. If hemodynamically unstable with hematochezia, place NGT or perform upper endoscopy (EGD) BEFORE colonoscopy to rule out upper source.
Is It Really Lower?
~10-15% of patients presenting with hematochezia have an upper GI source. A brisk upper GI bleed can transit fast enough to present as bright red blood per rectum. If the patient is hemodynamically unstable with hematochezia, consider upper GI source and place an NG tube or perform urgent EGD first.
Clues to upper source: hemodynamic instability, BUN/Cr ratio > 30, melanotic stool mixed with red blood, history of liver disease/varices/NSAID use
BUN/Cr ratio > 30 suggests upper GI bleed (absorbed blood products increase BUN)
🚨 Management
Initial Approach
Resuscitate
ABCs. Two large-bore IVs. Crystalloid resuscitation. Type and crossmatch. Transfuse pRBCs if Hgb < 7 (or < 9 if active ongoing hemorrhage or CAD). Correct coagulopathy -reverse anticoagulation if life-threatening bleed (4F-PCC for warfarin, idarucizumab for dabigatran, andexanet alfa for Xa inhibitors).
If hemodynamically unstable or high suspicion → NG lavage (if returns bile = upper source less likely, if returns blood = upper confirmed) or urgent EGD. BUN/Cr ratio > 30 → think upper.
Colonoscopy
Colonoscopy within 24h after adequate bowel prep ACG Guidelines, 2023. Diagnostic AND therapeutic (clipping, cauterization, epinephrine injection).
Key Evidence: Early colonoscopy (within 24h) did NOT reduce mortality or rebleeding in acute LGIB compared to elective timing COOLNG-2 (Strate), 2020. Restrictive transfusion (Hgb threshold 7 g/dL) is recommended over liberal (9 g/dL) for most GI bleeds Villanueva, 2013. CTA (CT angiography) can localize active bleeding for IR embolization when colonoscopy fails ACG Guidelines (Strate), 2023.
If Colonoscopy Fails to Localize
Test
When
Notes
CT angiography
Active bleeding (requires > 0.3-0.5 mL/min)
Fast, widely available. Localizes active extravasation Defined, 2019. Can guide IR embolization. Get BEFORE colonoscopy if hemodynamically unstable.
Tagged RBC scan (nuclear medicine)
Intermittent or slow bleeding (> 0.1 mL/min)
More sensitive than CTA for slow bleeds. Localizes to a region (not exact vessel). Takes hours. Less useful in acute management.
Angiography + embolization (IR)
Active hemorrhage not controlled by endoscopy
Requires active bleeding (> 0.5 mL/min). Can embolize the bleeding vessel. Risk: bowel ischemia (~5%).
Surgery
Massive, life-threatening, refractory bleed
Last resort. Segmental colectomy if source localized. Subtotal colectomy if source unknown (high morbidity). Always try to localize before surgery.
Anticoagulation in LGIB
Hold anticoagulation during active bleed + resuscitation
Restart early -within 7 days for most patients (if indication is strong: Afib, mechanical valve, recent VTE). Longer delay → increased thromboembolic events without mortality benefit from reduced rebleeding.
Aspirin for secondary cardiovascular prevention: do NOT stop (increased cardiac events outweigh GI bleed risk). Hold only if life-threatening hemorrhage.
Anticoagulant Management in LGIB: Hold anticoagulants during active bleed. For warfarin: give vitamin K if INR > 2.5 with significant bleeding. For DOACs: consider reversal only if life-threatening (idarucizumab (Praxbind) for dabigatran, andexanet alfa (Andexxa) for factor Xa inhibitors). Resume anticoagulation within 7 days if possible - delayed resumption increases thrombotic events Witt, 2017.
🧪 Workup
Initial Labs & Studies
CBC -Hgb/Hct (may lag in acute hemorrhage), platelets
BMP -BUN/Cr ratio > 20:1 suggests upper GI source (digested blood raises BUN)
Coags -PT/INR, PTT (especially if on anticoagulants or liver disease)
Type & Screen -always. Type & Cross if actively bleeding or Hgb dropping
Lactate -marker of hypoperfusion from hemorrhagic shock
Digital rectal exam -stool color (bright red, maroon, melena), hemorrhoids, masses
Colonoscopy within 24h -diagnostic AND therapeutic. Requires bowel prep (GoLYTELY 4L over 3–4h). Identifies source in 70–80%.
CT angiography -if hemodynamically unstable or too unstable for prep. Detects active bleeding > 0.3 mL/min.
EGD first -if BUN/Cr > 20, hemodynamic instability with hematochezia, or high suspicion for upper source (~15% of hematochezia is upper GI)
Tagged RBC scan -for intermittent or slow bleeds (> 0.1 mL/min). More sensitive but less specific than CTA. Takes hours.
Capsule endoscopy -for obscure GI bleeding when EGD and colonoscopy are negative
Oakland Score: Validated risk stratification tool for LGIB. Score ≤ 8 predicts safe discharge from ED without inpatient admission (99% sensitivity for no adverse outcomes). Components: age, sex, prior LGIB admission, HR, SBP, DRE findings, hemoglobin Oakland, 2017.
💊 Medications
Key Medications
Drug
Dose
Route
Notes
pRBCs
Transfuse if Hgb < 7 (or < 9 if CAD/active hemorrhage)
IV
Restrictive strategy preferred. 1 unit raises Hgb ~1 g/dL.
Pantoprazole (Protonix)
40 mg IV BID
IV
If upper source not yet excluded. Switch to PO once upper ruled out.
4F-PCC (KCentra)
25–50 units/kg IV
IV
Warfarin reversal for life-threatening bleed. Effect within 15 min.
Idarucizumab (Praxbind)
5 g IV
IV
Reversal of dabigatran. Complete reversal within minutes.
Andexanet alfa (Andexxa)
Fixed low or high dose, NOT weight-based: low 400 mg bolus then 4 mg/min × 2h; high 800 mg then 8 mg/min × 2h
IV
Reversal of rivaroxaban/apixaban only (not edoxaban). High dose only if last dose was apixaban > 5 mg or rivaroxaban > 10 mg within 8h. Use for life-threatening bleed only (expensive, and raises thrombotic risk).
GoLYTELY (PEG)
4L over 3–4h
PO/NGT
Bowel prep before colonoscopy. Can give via NGT if patient unable to drink.
📋 On Rounds
A patient presents with massive hematochezia and hemodynamic instability. What do you do first?
Resuscitate and consider an upper source. Massive hematochezia with hemodynamic instability has a ~15% chance of being from a brisk upper GI bleed (variceal, ulcer). Steps: (1) Large-bore IVs, crystalloid, activate massive transfusion if needed. (2) Urgent EGD or NG lavage to rule out upper source -this changes management completely (octreotide for varices, PPI for ulcer)
What is Heyde syndrome?
Aortic stenosis + GI bleeding from angiodysplasia. The mechanism: blood flowing through the stenotic aortic valve experiences high shear stress → destruction of von Willebrand factor (vWF) high-molecular-weight multimers → acquired von Willebrand disease type 2A → impaired hemostasis → bleeding from pre-existing angiodysplasia in the GI tract.
15% of patients presenting with hematochezia actually have an upper GI source. How do you catch this?
Bright red blood per rectum doesn't always mean lower GI bleed. A brisk upper GI bleed can transit fast enough to appear as hematochezia. Clues it's actually upper: (1) Hemodynamic instability disproportionate to rectal bleeding, (2) Elevated BUN/Cr ratio > 20 (blood protein digestion in upper GI → urea absorption), (3) NG tube with bloody aspirate (but a clear aspirate does NOT rule out upper -pyloric spasm can prevent reflux)
What is the role of CTA in acute lower GI bleed?
CT angiography can detect active bleeding if the rate is ≥ 0.3-0.5 mL/min (extravasation of contrast = active bleed). Best for: (1) hemodynamically unstable patient too sick for colonoscopy, (2) massive ongoing bleed where endoscopy can't visualize the source, (3) localizing the bleed for IR angiographic embolization. Limitation: if the bleeding is intermittent or has stopped, CTA will be negative.
What is the Oakland Score and when can you safely discharge an LGIB patient from the ED?
Oakland Score: validated risk stratification tool using age, sex, prior LGIB admission, HR, SBP, DRE findings, and hemoglobin. Score ≤ 8 identifies very low-risk patients safe for outpatient management (99% sensitivity for no adverse outcomes). Avoids unnecessary admissions for self-limited bleeding like hemorrhoids. Oakland, BMJ 2017.
Case 1: Diverticular Bleed
Presentation: 72M with PMH of HTN, diverticulosis presents with 3 episodes of painless maroon stools over 6 hours. Denies abdominal pain, NSAID use, or anticoagulation.
Vitals: HR 92, BP 128/74, afebrile. Abdomen soft, non-tender. Rectal: maroon stool, no hemorrhoids.
Management: Two large-bore IVs, resuscitate with lactated Ringer's (LR). Type & screen, crossmatch 2 units pRBC. Transfuse for Hgb < 7 (restrictive strategy). Hold aspirin if on it. GI consult → colonoscopy within 24 hours after bowel prep. If active diverticulum found → endoscopic hemostasis with clip placement or epinephrine injection. Hgb q6h during active monitoring.
Case 2: Severe Hematochezia with Hemodynamic Instability
Presentation: 65F on apixaban (Eliquis) for AFib presents with massive bright red blood per rectum, lightheadedness, and near-syncope.
Vitals: HR 120, BP 85/50, RR 22, pale and diaphoretic. Abdomen soft. Rectal: large-volume bright red blood.
Management: Activate massive transfusion protocol (MTP). Two large-bore IVs, lactated Ringer's (LR) wide open. Reverse anticoagulation with andexanet alfa (Andexxa) or 4-factor PCC (Kcentra) if unavailable. CTA abdomen/pelvis to localize active extravasation. If source identified → IR angiographic embolization. If no source on CTA or ongoing instability → surgery consult for possible subtotal colectomy. Elevated BUN/Cr → consider EGD to rule out upper source first.
Case 3: Ischemic Colitis
Presentation: 80F POD#3 from CABG presents with acute LLQ cramping pain and bloody diarrhea (6 episodes). History of PVD and CHF.
Vitals: HR 98, BP 108/62, T 37.8°C. Abdomen tender in LLQ, no peritoneal signs. Rectal: bloody stool.
Labs: Hgb 10.2, WBC 14K, lactate 2.1. CT abdomen shows colonic wall thickening at splenic flexure (watershed area) with pericolonic fat stranding, no pneumatosis or free air.
Management: Supportive care - bowel rest (NPO), IV lactated Ringer's (LR) for hydration, optimize cardiac output. Avoid vasopressors if possible (worsen ischemia). Broad-spectrum antibiotics (piperacillin-tazobactam (Zosyn)) if concern for transmural ischemia or sepsis. Serial abdominal exams q4-6h. Repeat imaging if worsening pain, rising lactate, or peritoneal signs. Surgery consult for perforation, gangrene, or clinical deterioration. Most cases resolve in 48-72h with supportive care.
📣 Sample Presentation
One-Liner
"Mr. Peters is a 74-year-old on apixaban presenting with 3 episodes of painless bright red blood per rectum. Hemodynamically stable, Hgb 9.8 from baseline 13.2."
Key Points to Cover on Rounds
Lower GI bleed, likely diverticular (painless, large-volume, elderly). Hemodynamically stable (HR 82, BP 134/78). Apixaban held. Hgb 9.8 -transfused 1 unit pRBC. Upper source ruled out (no melena, no hematemesis, BUN/Cr ratio normal). GI consulted -colonoscopy planned within 24h after bowel prep. If active bleeding identified → endoscopic hemostasis. If massive/unstable → CTA abdomen/pelvis. Bleeding has stopped spontaneously. Plan: colonoscopy tomorrow, resume apixaban after hemostasis confirmed.
Monitoring
Hgb q6-8h during active bleed
Hemodynamics
Stool output
Repeat Hgb after transfusion
⚡ Summary
Summary
Rule Out an Upper Source First
10 to 15% of patients presenting with hematochezia actually have a brisk upper GI bleed, transiting fast enough to arrive as bright red blood per rectum. If the patient is hemodynamically unstable with hematochezia, do an EGD before the colonoscopy. A raised BUN-to-creatinine ratio also points upward, from digested blood.
Most of It Stops on Its Own
80 to 85% of lower GI bleeds stop spontaneously, which is why the initial job is resuscitation and risk stratification rather than emergency intervention. Two large-bore IVs, type and cross, and serial hemoglobins, with the recognition that the first hemoglobin understates the loss.
Know the Common Causes by Age
Diverticular bleeding is the commonest overall and is classically painless and brisk. Then angiodysplasia (associated with aortic stenosis and chronic kidney disease), hemorrhoids, ischemic colitis, post-polypectomy bleeding, inflammatory bowel disease and malignancy.In anyone under 50 with painless bleeding, still consider malignancy, since incidence is rising in younger adults.
Transfuse Restrictively
Target a hemoglobin above 7 g/dL (above 8 in acute coronary syndrome). Liberal transfusion does not improve outcomes and worsens them in some groups, so a stable patient at 7.5 does not need a unit.
Do Not Rush the Colonoscopy
Early colonoscopy within 24 h did not reduce mortality or rebleeding compared with elective timing (Strate). An adequate bowel preparation matters more than speed, because an unprepped colon gives a poor yield and a repeat procedure. Prep and scope on the next available list in a stable patient.
When the Colonoscopy Cannot Localize It
CT angiography for active bleeding at 0.3 to 0.5 mL/min, which is fast, available and directs the interventional radiologist.Tagged red cell scintigraphy detects slower bleeding but localizes poorly.Angiographic embolization for ongoing bleeding, with surgery reserved for failure of everything else, since blind segmental resection has a high rebleed rate.
Handle Anticoagulation Proportionately
Hold the anticoagulant during active bleeding and reverse only for life-threatening hemorrhage, using the agent-specific reversal. Most patients should restart, typically within about 7 days once hemostasis is secure, because the thrombotic risk of stopping usually exceeds the rebleeding risk. Make the restart decision explicitly and document it, since these patients are routinely discharged with the drug simply omitted.
Recognize Ischemic Colitis as a Different Problem
Crampy abdominal pain followed by bloody diarrhea, typically in the watershed areas, in an older patient or after hypotension. It is managed supportively with bowel rest, fluids and antibiotics in selected cases, not with endoscopic hemostasis. Peritonitis, gangrene or a sepsis picture means surgery, so it needs serial abdominal examinations rather than a single reassuring scan.
Stable: resuscitate → colonoscopy within 24h (after prep). Unstable: CTA abdomen/pelvis → if active bleed → IR embolization. EGD first if upper source suspected.
⚠️ 15% Rule
15% of hematochezia is from upper GI source. Clues: hemodynamic instability disproportionate to rectal bleeding, BUN/Cr ratio > 20. If in doubt → EGD before colonoscopy.
💊 Key Drugs
TransfusepRBC if Hgb < 7
IVFLR resuscitation
Hold anticoagResume after hemostasis
PPIOnly if upper source suspected
⚠️ Pitfalls
Assuming hematochezia = lower source (15% are upper)
RoundsRx Licensed Content - Unauthorized Use Prohibited
EmergentNephrology
Hyponatremia
Na⁺ < 135 mEq/L -the most common electrolyte abnormality in hospitalized patients. The approach is systematic: (1) serum osmolality, (2) volume status, (3) urine studies. Correct slowly -osmotic demyelination syndrome is iatrogenic and devastating.
🔍 Systematic Approach
Step 1 -Serum Osmolality
Serum Osm
Category
Causes
< 275 (low)
Hypotonic (true hyponatremia)
Most cases. Proceed to Step 2. Includes post-TURP (transurethral resection of the prostate) absorption of glycine or sorbitol irrigant, which is genuinely hypo-osmolar and therefore swells the brain, unlike the mannitol row below.
275–295 (normal)
Isotonic (pseudohyponatremia)
Hyperlipidemia, hyperproteinemia (multiple myeloma). Lab artifact -true Na is normal. Check lipid panel + protein.
> 295 (high)
Hypertonic (translocational)
Hyperglycemia (#1 -correct Na for glucose: add 1.6 mEq/L Na for every 100 mg/dL glucose above 100), mannitol, IV contrast. The water is pulled out of cells, so the patient is hypertonic despite the low sodium: do NOT give hypertonic saline.
Iatrogenic Hyponatremia: Mannitol and Post-TURP Irrigant Absorption
Why these two sit together: both are hyponatremias you cause, and in both the tonicity is not what the sodium number implies. Mannitol produces a hypertonic hyponatremia, so reaching for hypertonic saline pushes in the wrong direction. Glycine absorption during a TURP produces a genuinely hypotonic hyponatremia that can seize and kill within hours. Identical low sodium on the chart, opposite physiology, opposite treatment. Measure the osmolality before you treat any hyponatremia you may have created.
Where you will actually meet it: mannitol given for raised intracranial pressure or cerebral edema (severe TBI, large hemispheric stroke, tumor with mass effect), for acute angle-closure glaucoma to drop the intraocular pressure, and mannitol used as the irrigant during monopolar TURP or hysteroscopy. The neuro-ICU patient on repeated dosing is the classic setup, because the risk is cumulative.
Mechanism: mannitol is an effective osmole, meaning it stays outside cells. It raises plasma osmolality, which pulls intracellular water out into the extracellular space, and that water dilutes the serum sodium. The sodium falls while the patient is hypertonic, which is the opposite of ordinary hyponatremia.
How to recognize it: the measured osmolality exceeds the calculated osmolality (2 × Na + glucose/18 + BUN/2.8), producing an osmolal gap, because mannitol is a solute the calculation does not include. A low sodium plus a high measured osmolality plus an osmolal gap in someone who received mannitol is the entire diagnosis.
Do not give hypertonic saline: the brain cells are already shrunken by the hypertonicity, so adding more tonicity worsens the problem you are trying to treat. The treatment is to stop the mannitol and let the kidney clear it, and dialysis if it has accumulated and the patient is symptomatic.
Accumulation is the setup, and renal impairment is the risk factor: mannitol is freely filtered and not reabsorbed, so clearance depends entirely on GFR. In AKI or CKD it builds up in the circulation and keeps pulling water out of cells. Follow the osmolal gap rather than the serum osmolality alone before each repeat dose, since a rising gap means drug is accumulating even when the calculated numbers look acceptable.
The second phase flips to hypernatremia: once mannitol reaches the tubule it drives an osmotic diuresis that loses proportionally more water than sodium. The same drug therefore causes hyponatremia early and hypernatremia later, so a patient on repeated dosing needs the sodium followed in both directions rather than checked once.
Watch the potassium too: water leaving cells carries potassium with it, so the identical shift that lowers the sodium can raise the potassium, and it does so fastest in the patients with the worst renal clearance.
Post-TURP (Transurethral Resection of the Prostate) Irrigant Absorption Syndrome
Why the irrigant is electrolyte-free in the first place: monopolar transurethral resection of the prostate (TURP) returns current through the patient's body to a grounding pad, so a conductive fluid such as saline would disperse the current and stop the loop cutting. That forces an electrolyte-free irrigant: glycine 1.5%, sorbitol, or mannitol. The hyponatremia is a direct consequence of the electrosurgical design, not of the surgery itself.
How it gets in: resection opens prostatic venous sinuses, and irrigation pressure exceeding venous pressure drives fluid straight into the circulation at roughly 20 mL/min, which is several liters across a long resection. About 1 L absorbed in an hour drops the sodium 5 to 8 mEq/L.
The triad is hyponatremia, hypo-osmolality, and hypervolemia. Glycine 1.5% runs about 200 mOsm/L and contains no sodium. The hypo-osmolality is what swells the brain (headache, confusion, seizures, and in severe cases herniation), while the hypervolemia is what floods the lungs.
The vital signs run backwards from what you expect: intraoperative trouble usually means tachycardia and hypotension, but irrigant absorption gives hypertension with bradycardia because the problem is volume overload. In an awake patient under spinal anesthesia, restlessness, nausea, confusion, and visual disturbance arrive first and give you a warning. Under general anesthesia that warning is erased, and the presentation may be an unexplained blood pressure rise, ECG changes, or a seizure. That early-warning value is a large part of why spinal anesthesia is favored for TURP.
Glycine carries two toxicities beyond the sodium: it is metabolized to ammonia, so hyperammonemic encephalopathy can persist after the sodium is fixed and explains the patient who stays confused despite a corrected number; and it is an inhibitory neurotransmitter in the retina, so it causes transient blurred vision or frank blindness. Transient blindness after a TURP is the glycine, not a stroke, and it resolves as the glycine clears, which saves the patient an emergent stroke workup.
Management: tell the surgeon to stop and terminate the resection, secure the airway, and send an immediate sodium and osmolality. Give 3% hypertonic saline for seizures or severe neurologic symptoms, and add a loop diuretic when there is pulmonary edema, since this patient is volume overloaded rather than dry. Use dialysis or CRRT for profound hyponatremia with volume overload, where hypertonic saline alone would worsen the fluid load.
Anticipate spontaneous overcorrection: as glycine is metabolized and the absorbed water is excreted, the sodium climbs on its own. Layer hypertonic saline on top of that and you can overshoot into osmotic demyelination. Recheck the sodium every 1 to 2 h and stop the hypertonic saline the moment symptoms resolve. This hyponatremia developed over minutes to hours, so the brain has not adapted and the demyelination risk is lower than in chronic hyponatremia, but respect the 24-hour ceiling anyway because you can rarely be certain the baseline was normal.
Prevention, and why this is now uncommon:bipolar resection keeps the current flowing between two electrodes millimeters apart on the resectoscope tip, so it never crosses the patient and normal saline can be used as the irrigant, which has made classic TURP syndrome rare. Also limit resection time, keep the irrigation bag height low to reduce driving pressure, and check a sodium during long resections rather than waiting for symptoms.
The Irrigant Determines the Physiology
Irrigant
Resulting picture
Extra toxicity beyond the sodium
Glycine 1.5% (~200 mOsm/L, most common in monopolar TURP)
Hypotonic hyponatremia with true hypo-osmolality, so cerebral edema is the danger
Metabolized to ammonia (encephalopathy outlasting the sodium correction) and transient visual disturbance or blindness from retinal inhibition
Sorbitol 3%
Hypotonic hyponatremia, same cerebral edema risk
Metabolized to fructose and glucose, so hyperglycemia and lactic acidosis, which matters most in diabetics
Mannitol 5% (~275 mOsm/L, near iso-osmolar)
Dilutional hyponatremia without hypo-osmolality, so volume overload dominates rather than cerebral edema
Intravascular expansion and pulmonary edema, then an osmotic diuresis as it is excreted
Normal saline (possible only with bipolar resection)
No hyponatremia, which is the entire reason bipolar equipment displaced monopolar
Large absorbed volumes can still cause hyperchloremic metabolic acidosis and fluid overload
Volume resuscitation with NS. Na will correct as volume is restored. Watch for overcorrection -once ADH stimulus (hypovolemia) is removed, kidneys dump free water rapidly.
Euvolemic (no edema, no orthostasis -hardest to assess)
Fluid restriction + treat underlying disease. Diuretics for HF/cirrhosis. Dialysis if ESKD.
Hypervolemic, acute and iatrogenic post-TURP or operative hysteroscopy
> 20 (the sudden volume expansion drives a natriuresis, which lowers the sodium further)
Absorbed hypotonic irrigant: glycine 1.5% or sorbitol during monopolar resection. Suspect it on hypertension with bradycardia, the reverse of the usual intraoperative crash, plus confusion or visual disturbance in an awake patient
Stop the resection first. This is the one hypervolemic hyponatremia where you still give 3% hypertonic saline for seizures or severe symptoms, adding a loop diuretic for pulmonary edema. Full section
Step 3 -Key Labs to Order
Serum osmolality (first -classifies the hyponatremia)
Urine sodium (renal vs extrarenal losses in hypovolemic; confirms SIADH if > 40 in euvolemic)
Serum glucose (correct for hyperglycemia: add 1.6 per 100 above 100)
TSH, AM cortisol (rule out hypothyroidism and adrenal insufficiency before diagnosing SIADH)
Osmolal gap (measured minus calculated osmolality) whenever the patient received mannitol or absorbed irrigant -an unmeasured osmole means you are dealing with a translocational or iatrogenic hyponatremia, not a volume problem, and the treatment changes completely
🚨 Management
Correction Rates
The danger of hyponatremia treatment is NOT the low sodium -it's correcting too fast. Osmotic demyelination syndrome (ODS) is iatrogenic, irreversible, and devastating. ODS Prevention Study, 2010
Scenario
Max Correction Rate
Treatment
Chronic (> 48h or unknown duration)
≤ 8 mEq/L in 24h (some guidelines use ≤ 10). High-risk for ODS: ≤ 6 mEq/L in 24h.
Can correct faster -brain hasn't adapted. Still aim for ≤ 10–12 mEq/L in 24h.
More aggressive treatment acceptable. Still monitor closely.
Symptomatic (seizures, coma, severe AMS)
Immediate goal: raise Na by 4–6 mEq/L in first 6h to stop symptoms. Then ≤ 8 total in 24h.
3% hypertonic saline 100–150 mL IV bolus over 10–20 min.SALSA, 2021 May repeat × 2. ICU. Check Na q2h.
Osmotic Demyelination Syndrome (ODS)
Occurs 2–6 days after overcorrection -not immediately
Central pontine myelinolysis → "locked-in syndrome" (quadriplegia, inability to speak/swallow, preserved consciousness)
Risk factors for ODS: chronic hyponatremia (> 48h), alcoholism, malnutrition, hypokalemia (correct K⁺ simultaneously -K⁺ correction counts toward Na correction!), liver disease, Na < 105
If overcorrecting (Na rising too fast): (1) D5W infusion (free water to re-lower Na), (2) DDAVP 2 mcg IV q8h (clamp urine output → stop Na from rising further), (3) target: bring Na back within safe correction range
🔄 Updated Practice: Old teaching: correct sodium no more than 10-12 mEq/L in 24 hours. Updated: the recommended limit is now ≤8 mEq/L in any 24-hour period for patients at high risk for osmotic demyelination syndrome (ODS) -chronic hyponatremia (>48h), alcoholism, malnutrition, hypokalemia, liver disease. For truly acute hyponatremia (<48h, e.g., exercise-associated, postoperative), faster correction is safe. If overcorrected: give back free water (D5W) and consider desmopressin (DDAVP) 2 mcg IV to re-lower sodium.
Danger point: hypovolemic hyponatremia corrected with NS. Once volume is restored, the ADH stimulus disappears → kidneys suddenly excrete massive free water → Na shoots up rapidly → osmotic demyelination syndrome (ODS) risk. Prevention: anticipate it, cap correction ≤ 8 mEq/L in any 24h period in high-risk patients (chronic hyponatremia, alcoholic, malnourished, liver disease, hypokalemia). If overshooting: D5W infusion ± DDAVP 2 mcg IV to re-lower Na into the safe range.
Swipe for more examples
📋 Case 1, SIADH from SCLC
Patient: 68F with SCLC, found lethargic, Na⁺ 118 mEq/L.
Step 1 -Is this real? Serum osm: 248 (< 280 = true hypoosmolar hyponatremia). Not pseudohyponatremia.
Step 2 -Assess volume status:
Exam: Mucous membranes moist, no edema, no JVD, skin turgor normal → euvolemic
TSH: normal. AM cortisol: normal (rules out hypothyroid and adrenal insufficiency)
Diagnosis: SIADH from SCLC (paraneoplastic ADH secretion)
Step 3 -Treatment:
Symptomatic (lethargic) → 3% hypertonic saline 100 mL IV bolus over 10 min. Recheck Na in 2h.
Na went 118 → 121 (+3 in 2h) -good. Symptoms improving.
Target: correct ≤ 8 mEq/L in first 24h (risk of osmotic demyelination if faster)
Fluid restriction 1L/day for maintenance
If refractory SIADH: tolvaptan (Samsca) 15mg PO daily (check Na q6h -potent)
📋 Case 2, Beer Potomania
Patient: 48M heavy beer drinker (12+ beers/day), found confused. Na⁺ 108 mEq/L. No edema. Uosm 58 (maximally dilute).
Diagnosis: Beer potomania, massive free water intake with minimal solute intake → kidneys cannot excrete the water load despite maximally dilute urine.
Treatment:
STOP free water intake. Normal saline is usually sufficient (not hypertonic) because once solute intake resumes, kidneys correct rapidly.
Monitor Na q2h closely.
If correcting > 8 mEq/day → give DDAVP 2 mcg IV q8h + D5W to slow correction.
⚠️ DANGER: These patients auto-correct too fast once admitted and beer is stopped. The kidneys suddenly have enough solute to excrete free water → Na shoots up.
Key lesson: Beer potomania corrects itself dangerously fast when you admit the patient and stop beer. DDAVP rescue may be needed to SLOW correction.
📋 Case 3, SIADH from SSRI
Patient: 72F started on sertraline 3 weeks ago, presents with nausea and confusion. Na⁺ 122 mEq/L. Euvolemic.
Labs: Uosm 580 (inappropriately concentrated). Urine Na 65. TSH and cortisol normal.
Diagnosis: Classic SIADH from SSRI.
Treatment:
Fluid restriction 1–1.2 L/day (first-line for SIADH).
If not improving → salt tabs 1–2 g TID + loop diuretic (furosemide 20 mg, forces dilute urine).
Consider stopping sertraline or switching to a less SIADH-prone antidepressant.
Avoid hypertonic saline unless symptomatic (seizures, severe AMS).
Key lesson: Always check the med list for SIADH causes. SSRIs are the #1 medication cause. Fluid restriction is first-line, not hypertonic saline.
RoundsRx Licensed Content - Unauthorized Use Prohibited🧪 Workup
Diagnostic Workup -Hyponatremia
Systematic approach: (1) Serum osmolality → (2) Volume status → (3) Urine studies. Do NOT diagnose SIADH without first ruling out hypothyroidism and adrenal insufficiency.
Differentiates renal from extrarenal sodium losses in hypovolemic states; confirms SIADH in euvolemic.
UNa < 20 = extrarenal losses (GI, third-spacing) or effective hypovolemia (CHF, cirrhosis). UNa > 40 in euvolemic state = SIADH. UNa > 20 in hypovolemic = renal losses (diuretics, adrenal insufficiency).
Volume status (clinical)
Essential physical exam -guides entire differential and treatment.
Hypothyroidism is a reversible cause -must exclude before diagnosing SIADH.
Severe hypothyroidism → decreased free water clearance → hyponatremia. Treat thyroid disease first.
AM cortisol
Adrenal insufficiency mimics SIADH (euvolemic, high UNa). Must exclude before SIADH diagnosis.
AM cortisol < 3 = adrenal insufficiency likely. 3-15 = indeterminate → ACTH stimulation test. > 15 = AI unlikely.
Serum glucose
Correct Na for hyperglycemia (translocational hyponatremia).
Corrected Na = measured Na + 1.6 × [(glucose - 100) / 100]. If corrected Na is normal → not true hyponatremia.
💊 Medications
Drug Therapy -Hyponatremia
Drug
Dose
Route
Indication
Key Notes
3% Hypertonic saline
100-150 mL IV bolus over 10-20 min. May repeat × 2 (max 3 boluses).
IV
Severe symptomatic hyponatremia (seizures, coma, severe AMS)
ICU setting. Goal: raise Na by 4-6 mEq/L in first 6h to stop symptoms. Check Na q2h. Rapid intermittent bolus is as effective and safer than continuous infusion SALSA, 2021.
Effective if urine osmolality is not extremely high. Poor compliance limits effectiveness. Calculate free water clearance to predict response.
NaCl tablets (salt tabs)
1-3 g PO TID
PO
Chronic SIADH (with or without loop diuretic)
Often combined with furosemide 20 mg daily -the diuretic promotes free water excretion while salt tabs replenish sodium. Effective outpatient strategy.
Furosemide
20-40 mg PO daily
PO
Combined with salt tabs for chronic SIADH
Impairs urinary concentration → promotes electrolyte-free water excretion. Only effective when combined with adequate sodium intake (salt tabs).
Tolvaptan (Samsca)
15 mg PO daily (may increase to 30-60 mg)
PO
Refractory SIADH or hypervolemic hyponatremia not responding to fluid restriction
V2 receptor antagonist ("vaptan") -blocks ADH at collecting duct → aquaresis (free water loss). Must initiate inpatient. Check Na q6h for first 24h. Hepatotoxicity risk -do not use > 30 days. Do NOT use in hypovolemic hyponatremia.
Demeclocycline
300-600 mg PO BID
PO
Alternative for chronic SIADH (if tolvaptan not available/tolerated)
Tetracycline that induces nephrogenic DI. Slow onset (3-5 days). Nephrotoxic -avoid in liver disease. Largely replaced by tolvaptan.
DDAVP (desmopressin)
2 mcg IV q8h
IV
ODS rescue -given when Na is overcorrecting too rapidly
Clamps urine output → stops further Na correction. Combine with D5W (3-6 mL/kg/hr) to actively re-lower Na. Target: bring correction rate back to ≤ 8 mEq/L in 24h.
D5W (5% dextrose)
3-6 mL/kg/hr
IV
ODS rescue -free water to re-lower sodium if overcorrecting
Used with DDAVP. The dextrose is metabolized, leaving free water. Start immediately if Na rising > 8-10 mEq/L in 24h.
📋 On Rounds
Why does correcting hypokalemia matter in hyponatremia?
Potassium is osmotically active and contributes to the Na correction rate. When you give IV KCl, K⁺ enters cells and Na⁺ comes out (to maintain electrochemical balance via the Na⁺/K⁺-ATPase). This means every mEq of K⁺ you give raises the serum Na by approximately the same amount as giving a mEq of Na. If you're correcting hypokalemia aggressively alongside hyponatremia, the Na may rise faster than you expect.
A urine osmolality of 50 mOsm/kg in a hyponatremic patient tells you what?
The kidneys are doing their job -maximally diluting urine. This means ADH is appropriately suppressed and the kidneys are trying to excrete free water. The hyponatremia is from water intake exceeding the kidney's diluting capacity. Differential: psychogenic polydipsia (> 15–20 L/day overwhelms even normal kidneys), beer potomania (low solute intake → low obligate urine output → can't excrete enough water), tea-and-toast diet (same mechanism).
You are correcting hyponatremia and realize you've already gone up 10 mEq in 18 hours. What do you do?
ODS rescue protocol -act immediately: (1) Stop all hypertonic saline and salt tabs, (2) Give D5W at 3-6 mL/kg/hr (free water to re-lower sodium), (3) Give DDAVP 2 mcg IV q8h (makes kidneys retain free water, prevents further correction). (4) Recheck Na q2h until it falls back to the safe correction rate (≤ 8 mEq/24h, some experts say ≤ 6 in high-risk patients).
What are the most dangerous medications that cause SIADH?
SSRIs are the #1 drug cause of SIADH (sertraline, fluoxetine, paroxetine -onset typically 1-4 weeks). Other common offenders: carbamazepine/oxcarbazepine (direct ADH-like effect on collecting duct), cyclophosphamide (especially with high-volume hydration), vincristine (neuropathic ADH release), opioids, PPIs, NSAIDs, ecstasy/MDMA (causes acute hyponatremia from both ADH release and excessive water intake → can be fatal).
Clinical Examples
📋 Case 1, SIADH from SSRI with Overcorrection Risk
Patient: 72 y/o F on sertraline x3 weeks, presents with confusion. Na⁺ 112 (was 128 two weeks ago).
Key findings: Serum osm 238, urine osm 480, UNa 52, euvolemic. TSH and cortisol normal. SIADH from sertraline.
Management:
Stop sertraline, removing the SIADH stimulus may cause rapid free water excretion
Fluid restriction < 1L/day + salt tabs 1g TID
Na rose 10 mEq in 18h (overcorrection), start ODS rescue: D5W + DDAVP 2 mcg IV q8h
Re-lower Na back to safe correction rate (≤ 8 mEq/24h); recheck Na q2h
Teaching point: When the SIADH stimulus is removed, ADH drops and free water is excreted rapidly, causing overcorrection. ODS is devastating and irreversible. High-risk patients need proactive DDAVP clamping.
📋 Case 2, Severe Symptomatic Hyponatremia with Seizures
Patient: 55 y/o M with SCLC, found seizing at home. Na⁺ 104, obtunded.
Key findings: Serum osm 218, urine osm 640, UNa 68, GCS 8. Euvolemic. Ectopic ADH from SCLC.
Management:
3% NaCl 100-150 mL bolus over 10 min, repeat x1 if still seizing
Target 4-6 mEq/L acute rise to stop seizures, then ≤ 8 mEq/24h total
Check Na q2h during correction; DDAVP 2 mcg IV q8h proactively to prevent overcorrection
ICU admission, oncology for underlying SCLC treatment
Teaching point: Seizures from hyponatremia require emergent 3% NaCl, the one scenario where rapid correction is indicated. Target only enough rise to stop symptoms, then strictly limit total correction.
📋 Case 3, Beer Potomania (Low Solute Hyponatremia)
Treatment: normal diet (increase solute) + fluid restriction
HIGH overcorrection risk when diet resumes, use prophylactic DDAVP
Teaching point: Urine osm < 100 rules out SIADH. Beer potomania corrects rapidly when normal diet resumes, proactive DDAVP is essential to prevent ODS. SALT-1/2, 2006 showed tolvaptan is effective for SIADH but is NOT appropriate for low-solute states.
📣 Sample Presentation
One-Liner
"Mrs. Lee is a 68-year-old with SCLC presenting with Na⁺ 118, serum osm 252, urine osm 520, urine Na 45, euvolemic on exam. Consistent with SIADH from malignancy."
Key Points to Cover on Rounds
Euvolemic hypoosmolar hyponatremia. Urine osm 520 (inappropriately concentrated), UNa 45 (>40). TSH and cortisol normal. Etiology: SIADH from SCLC. Asymptomatic (no seizure, no AMS). Treatment: fluid restriction <1L/day. Na trending 118→120→122 over 24h (rate 4 mEq/24h -safe). Salt tabs 1g TID added. If refractory → tolvaptan 15 mg daily SALT-1/2, 2006 (monitor in-hospital, check Na q6h). Goal: ≤8 mEq/L correction per 24h to avoid ODS. Plan: treat underlying malignancy, continue fluid restriction.
Monitoring -Hyponatremia Correction
Parameter
Frequency
Target / Action
Serum sodium
q2h if on hypertonic saline; q4-6h during active correction; q6-8h once stable
Max correction ≤ 8 mEq/L in any 24h period (≤ 6 in high-risk: alcoholism, malnutrition, hypokalemia, liver disease, Na < 105). If overcorrecting → DDAVP + D5W rescue immediately.
Serum osmolality
At baseline, then q12-24h during correction
Should rise proportionally with Na. Guides assessment of correction adequacy.
Urine output
q1-2h during active treatment
Sudden brisk water diuresis (> 200 mL/hr of dilute urine) = danger sign for overcorrection. This happens when ADH stimulus is removed (e.g., volume resuscitation in hypovolemic hyponatremia). Start DDAVP preemptively if UOP surges.
Neurological status
q2-4h during active correction
Improving: resolution of confusion, seizures, lethargy = adequate correction. New dysarthria, dysphagia, quadriparesis 2-6 days after correction = ODS -MRI brain, neurology consult.
Potassium
With each Na check
K⁺ correction counts toward Na correction (K⁺ enters cells, Na⁺ comes out). If repleting K⁺ aggressively, account for this in your correction rate calculation.
I&Os
Strict q1h during active treatment
Track all free water intake (IV and PO). Ensure fluid restriction is enforced if indicated. Document urine osmolality if available (Uosm < 200 on tolvaptan = expected).
Overcorrection rescue protocol: If Na rises > 8-10 mEq/L in 24h → (1) Stop all hypertonic saline and salt tabs, (2) D5W at 3-6 mL/kg/hr, (3) DDAVP 2 mcg IV q8h, (4) Recheck Na q2h until back within safe range. Act immediately -ODS is irreversible.
⚡ Summary
Summary
Symptoms Outrank Etiology
Seizures or severe obtundation mean hypertonic saline now: 3% NaCl 100 to 150 mL over 10 to 20 min, repeatable twice.Target an acute rise of only 4 to 6 mEq/L, because that is enough to shrink the brain and stop the seizing, and any more starts spending the 24-hour correction budget. The workup runs after the brain is safe, not before.
First Lab Question: Is It Even Hypotonic?
Check serum osmolality before anything else. Below 275 is true hypotonic hyponatremia. Normal osmolality is pseudohyponatremia, a lab artifact from paraproteins, severe lipemia or IVIG: the sodium is fine, so treating it harms. High osmolality is translocational, glucose or mannitol pulling water out of cells; correct the sodium up 2.4 mEq/L per 100 mg/dL of glucose above 100, because fixing the glucose fixes the sodium.
Urine Osmolality Asks: Is ADH On?
Urine osm below 100 means ADH is appropriately off and the kidney is dumping water as fast as it can: the problem is intake outrunning it (primary polydipsia, beer potomania, tea-and-toast low solute), fixed by restricting water and feeding solute. Urine osm above 100 means ADH is acting, and the question becomes whether that ADH release is appropriate (hypovolemia) or not (SIADH).
Urine Sodium Splits the ADH-On Group
Urine Na below 20 to 30 means the kidney is clinging to sodium: true hypovolemia, or the low effective arterial volume of CHF, cirrhosis and nephrotic syndrome, where total body water is up but the kidney perceives emptiness. Urine Na above 30 to 40 in a euvolemic patient points to SIADH, but only after excluding hypothyroidism and adrenal insufficiency (check TSH and cortisol), which mimic it and have their own fixes. Diuretic use muddies the urine Na, so interpret it off diuretics when possible.
Treatment Follows the Category
Hypovolemic: isotonic fluid, and expect the sodium to jump once volume is restored and ADH switches off abruptly, so recheck early. Hypervolemic: fluid and sodium restriction plus loop diuretics, treating the failing organ. SIADH: fluid restriction under 1 L/day first (water is the poison, so remove the water), then salt tabs with a loop diuretic, then tolvaptan, inpatient only with sodium checks every 6 h, because vaptans can overcorrect rapidly. Always hunt the SIADH cause: drugs, small cell lung cancer, CNS and pulmonary disease.
The Ceiling: 8 mEq/L per 24 h
Never correct more than 8 mEq/L in 24 h, and hold to 4 to 6 in high-risk patients: sodium 105 or below, alcohol use disorder, malnutrition, hypokalemia, advanced liver disease. The brain has already adapted by shedding osmolytes, so a fast rise dehydrates oligodendrocytes and causes osmotic demyelination: quadriparesis, pseudobulbar palsy, locked-in syndrome, appearing 2 to 6 days later and largely irreversible. Chronic hyponatremia is the dangerous one to correct; the adaptation is complete.
Overcorrection Rescue
If the sodium is rising past the limit, actively re-lower it: D5W plus DDAVP 2 mcg IV q8h. This is not optional damage control; re-lowering within the same day prevents demyelination. The classic setting is the hypovolemic patient whose ADH shut off after fluids, producing a brisk free-water diuresis: a rising urine output with dilute urine is the early warning to act.
Not checking TSH and cortisol (must exclude before diagnosing SIADH)
Free water restriction while on tolvaptan (dangerous combo)
IV NS for hypovolemic hyponatremia in SIADH (worsens it)
NephrologyCore Skill
Acid-Base Disorders
A systematic 5-step approach to every ABG. pH → primary disorder → compensation → anion gap → delta-delta. Master this and you'll never be stumped by an ABG again.
🧪 5-Step ABG Interpretation
Step 1 -Look at the pH
pH
Primary Process
< 7.35
Acidemia (acidosis is the dominant process)
7.35–7.45
Normal (or mixed disorder with complete compensation)
Expected PCO₂ = 0.7 × [HCO₃] + 21 (± 2). Or: PCO₂ rises ~0.7 for each 1 mEq/L rise in HCO₃.
Acute respiratory acidosis
HCO₃ rises 1 per 10 mmHg ↑ PCO₂
Chronic respiratory acidosis
HCO₃ rises 3.5 per 10 mmHg ↑ PCO₂
Acute respiratory alkalosis
HCO₃ falls 2 per 10 mmHg ↓ PCO₂
Chronic respiratory alkalosis
HCO₃ falls 5 per 10 mmHg ↓ PCO₂
If compensation is more or less than expected → there's a second (mixed) disorder. Example: metabolic acidosis with PCO₂ lower than Winter's predicted → concurrent respiratory alkalosis (sepsis?).
Step 4 -Calculate the Anion Gap
AG = Na − (Cl + HCO₃). Normal: 12 ± 4 (or 8 ± 4 if albumin-corrected). Correct for albumin: for every 1 g/dL albumin below 4 → add 2.5 to the AG.
MUDPILES (AG Elevated > 12)
Cause
Mechanism
M ethanol
Alcohol dehydrogenase converts methanol to formic acid, which inhibits cytochrome oxidase and damages the retina (optic disc edema, blindness). Treat with fomepizole + dialysis.
U remia
Failing kidneys cannot excrete sulfates, phosphates, urate, and other organic anions. Develops at GFR < 20.
D KA (also alcoholic KA, starvation KA)
Insulin deficiency (or alcohol-induced NADH excess) drives lipolysis and hepatic ketogenesis. Accumulating β-hydroxybutyrate and acetoacetate are the unmeasured anions.
P ropylene glycol
Solvent in IV lorazepam, phenobarbital, and diazepam infusions. Metabolized by alcohol dehydrogenase to lactic acid. Classic iatrogenic ICU cause after high-dose benzo drips.
I soniazid / Iron
INH depletes pyridoxine (B6) and inhibits GABA synthesis → refractory seizures + lactic acidosis. Treat with high-dose pyridoxine 1:1 (g per g of INH ingested). Iron OD disrupts mitochondrial oxidative phosphorylation → lactate.
L actic acidosis #1 cause in hospital
Type A: tissue hypoperfusion or hypoxia (sepsis, shock, ischemia, severe anemia, CO poisoning). Type B: drugs (metformin, linezolid, propofol, NRTIs, β2 agonists), liver failure, malignancy (Warburg effect), thiamine deficiency, D-lactic from short bowel. See full breakdown in Differentials tab.
E thylene glycol
Antifreeze. Metabolized to glycolic acid (AG acidosis) and oxalic acid (calcium oxalate crystalluria → AKI). Treat with fomepizole + dialysis. Bedside clues: oxalate crystals in urine, fluorescence under Wood's lamp (some products).
S alicylates
Uncouples mitochondrial oxidative phosphorylation → AG acidosis. Also directly stimulates the medullary respiratory center → early respiratory alkalosis. The classic mixed disorder (AGMA + resp alkalosis) is the giveaway. Tinnitus is the bedside tell.
HARDUPS (AG Normal / Hyperchloremic)
Cause
Mechanism
H yperalimentation (TPN)
Cationic amino acids (lysine, arginine, histidine) in TPN generate HCl as they are metabolized. Modern TPN includes acetate buffer to offset this; classic boards still tests it.
A ddison's / Acetazolamide
Addison's (adrenal insufficiency): low aldosterone → impaired distal H+ and K+ excretion (mimics Type 4 RTA, hyperK). Acetazolamide: blocks proximal carbonic anhydrase → bicarbonate wasted in urine.
R TA
Type 1 (distal): α-intercalated cells cannot secrete H+ → urine pH > 5.5, hypoK, kidney stones (Sjögren, SLE). Type 2 (proximal): impaired HCO3- reabsorption → Fanconi syndrome, hypoK. Type 4: hypoaldosteronism (DM, ACEi/ARB, TMP-SMX, heparin, spironolactone) → hyperK. Most common RTA.
D iarrhea #1 cause of NAGMA
Direct loss of bicarbonate-rich small bowel and colonic secretions. Urine AG is negative (kidneys appropriately excrete NH4+), distinguishing it from RTA.
U reteral diversion (ileal conduit, ureterosigmoidostomy)
Bowel mucosa exchanges urinary Cl- for HCO3-. The longer the urine sits in contact with bowel, the more HCO3- is lost.
P ost-hypocapnia / Pancreatic fistula
Post-hypocapnia: chronic respiratory alkalosis caused renal HCO3- wasting as compensation; when PaCO2 abruptly normalizes (e.g., post-intubation), bicarb is now inappropriately low. Pancreatic fistula or biliary drain: direct loss of HCO3-rich secretions.
S aline (NS resuscitation)
Large-volume 0.9% NS delivers a Cl- load that displaces HCO3- extracellularly = hyperchloremic dilutional acidosis. Switch to LR or PlasmaLyte for ongoing resuscitation. SMART 2018
AG metabolic acidosis + concurrent non-AG metabolic acidosis (the bicarb dropped more than expected from the AG alone → additional acid or bicarb loss)
1–2
Pure AG metabolic acidosis (the drop in bicarb matches the rise in AG)
> 2
AG metabolic acidosis + concurrent metabolic alkalosis (bicarb is higher than expected → something is raising it -vomiting, diuretics, bicarb administration)
📋 Differentials
Metabolic Alkalosis
CLEVER PD (Causes of Metabolic Alkalosis)
Cause
Mechanism
C ontraction (volume depletion) SALINE-RESP
Loss of Cl⁻-rich extracellular fluid (vomiting, diuretics, sweating) makes the proximal tubule reabsorb Na⁺ paired with HCO3- instead of Cl⁻. Volume contraction also activates RAAS → aldosterone drives distal H⁺ secretion. Together: rising and maintained HCO3-.
L icorice (glycyrrhizic acid) SALINE-RESIST
Inhibits renal 11β-HSD2, which normally inactivates cortisol to cortisone in the collecting duct. Unopposed cortisol activates the mineralocorticoid receptor → apparent mineralocorticoid excess (Na retention, K⁺ and H⁺ wasting). Mimics primary hyperaldosteronism but with low renin AND low aldosterone.
E ndocrine (Conn's, Cushing's, Bartter, Gitelman) SALINE-RESIST
Conn's: autonomous aldosterone → distal Na/K and Na/H exchange. Cushing's: excess cortisol overwhelms 11β-HSD2. Bartter: defective NKCC2 in TAL = "endogenous loop diuretic" (hypoK, hypoCl, alkalosis, normal BP). Gitelman: defective NCC in DCT = "endogenous thiazide" (adds hypoMg).
V omiting / NG suction SALINE-RESPCommon
Direct loss of HCl from gastric secretions raises serum HCO3- (every H⁺ lost = one HCO3- generated). Concurrent volume and Cl⁻ depletion add a contraction component, perpetuating the alkalosis until both are repleted.
E xcess alkali SALINE-RESP
Direct HCO3- load: IV sodium bicarbonate, milk-alkali syndrome (CaCO3 antacids + milk → hyperCa, AKI, alkalosis; full breakdown in Hypercalcemia topic), massive transfusion (citrate metabolized to bicarb by the liver), TPN with acetate buffer overload.
R efeeding SALINE-RESP
Carb load triggers insulin surge → cellular uptake of K⁺, phos, Mg, and intracellular H⁺ shift. The resulting hypokalemia and intracellular acidosis maintain extracellular alkalosis. Watch closely in malnourished patients restarting nutrition. Full breakdown → Refeeding Syndrome topic.
P ost-hypercapnia SALINE-RESP
Chronic respiratory acidosis (COPD) caused renal HCO3- retention as compensation. When PaCO2 abruptly normalizes (post-intubation overventilation, NIV, mechanical hyperventilation), HCO3- is left inappropriately high → unmasked metabolic alkalosis. Avoid by lowering ventilator support gradually.
D iuretics (loop, thiazide) RESIST (active)RESP (off)
Block Na/Cl reabsorption proximal to the collecting duct → increased distal Na⁺ delivery + secondary hyperaldosteronism → distal Na/K and Na/H exchange. Plus volume contraction, hypoK, and hypoCl. While dosed: urine Cl > 20 (resistant). After stopping: urine Cl falls, becomes responsive. K⁺-sparing diuretics (spironolactone, eplerenone, amiloride) do NOT cause alkalosis (and can correct it).
NS (volume + chloride repletion). Correct the deficit.
> 20 mEq/L
Chloride-resistant
Hyperaldosteronism (Conn syndrome), Cushing's, Bartter/Gitelman, active diuretic use, severe hypokalemia
Treat underlying cause. K⁺ repletion. Spironolactone if hyperaldosteronism.
Why NS and K⁺ correct chloride-responsive metabolic alkalosis:
NS (volume + Cl⁻): Volume depletion (from vomiting, NG suction, diuretics) makes the proximal tubule avidly reabsorb Na⁺. With Cl⁻ also depleted, Na⁺ has to be reabsorbed paired with HCO₃⁻ instead of Cl⁻, which keeps serum HCO₃⁻ high. Volume contraction also activates aldosterone, which drives distal Na⁺/H⁺ exchange and generates more HCO₃⁻. Giving NS restores volume (turns off RAAS) and supplies Cl⁻ so the proximal tubule pairs Na⁺ with Cl⁻ again, letting the kidney finally dump excess HCO₃⁻ in the urine.
K⁺ repletion: Hypokalemia maintains the alkalosis through three mechanisms. (1) Transcellular shift: K⁺ leaves cells in exchange for H⁺ moving in, producing intracellular acidosis but extracellular alkalosis. (2) Distal tubule: when K⁺ is low, the principal cell swaps Na⁺ for H⁺ instead of K⁺, dumping more H⁺ in the urine. (3) Proximal tubule: hypokalemia stimulates ammoniagenesis (NH₄⁺ excretion), and each NH₄⁺ excreted generates a new HCO₃⁻. Replacing K⁺ shuts all three down. You cannot fully correct metabolic alkalosis without correcting K⁺.
Most common RTA. Diabetic nephropathy, ACEi/ARBs, spironolactone, TMP-SMX, heparin
Pearl: Always calculate the corrected AG (for albumin) and delta-delta ratio to identify mixed disorders.
Lactic Acidosis: Types A and B
Cohen-Woods classification. Two types only: A (hypoperfusion) and B (everything else). B is subdivided into B1, B2, B3. Every named cause (MALA, propofol infusion, D-lactic acidosis) sits inside one of these buckets.
Type
Mechanism
Causes
Type A Most common
Tissue hypoperfusion or hypoxia. Anaerobic glycolysis surges.
Shock (septic, cardiogenic, hypovolemic, obstructive), regional ischemia (mesenteric, limb, compartment syndrome), severe hypoxemia, severe anemia, CO poisoning, post-arrest, seizures, heavy exertion.
Type B1 Underlying disease
Disease impairs lactate clearance or shifts metabolism without overt hypoperfusion.
Liver failure (impaired clearance), malignancy (Warburg effect; classic in leukemia/lymphoma), sepsis (overlaps with A), thiamine deficiency, diabetes, pheochromocytoma, short bowel / SIBO → D-lactic acidosis.
Type B2 Drugs / toxins
Mitochondrial toxicity, β2 stimulation, or impaired clearance.
D-lactic acidosis (bacterial overgrowth): Short bowel syndrome and SIBO let gut bacteria (Lactobacillus, Streptococcus bovis, Bifidobacterium) ferment unabsorbed carbohydrate into D-lactate, the stereoisomer humans cannot metabolize efficiently (we lack effective D-lactate dehydrogenase). Triggered by carb-rich meals. Presents as episodic encephalopathy (slurred speech, ataxia, confusion; looks intoxicated) with a wide anion gap. The trap: the standard lactate assay measures L-lactate only, so it returns normal despite the gap. You must specifically order a D-lactate level. Treatment: low-carb diet, oral non-absorbable antibiotics (metronidazole, neomycin, vancomycin, rifaximin) to suppress overgrowth, IV fluids, bicarb if severe. Sits inside Type B1 in Cohen-Woods (the "D" refers to the molecular isomer, not a separate Cohen-Woods type).
Bedside framing: Lactate > 4 with hypotension → Type A, resuscitate first. Lactate elevated but patient looks well-perfused → Type B (drugs, liver, malignancy, thiamine). Persistent lactate despite resuscitation → recheck for missed ischemia (mesenteric, limb), failed source control, then consider metformin, linezolid, thiamine deficiency, malignancy.
Toxic Alcohols (suspect when AG ↑ + osmolar gap > 10)
Osmolar gap = measured osm − (2×Na + glu/18 + BUN/2.8). Normal < 10. The trap: the gap shrinks as the parent alcohol is metabolized to its toxic acid, so a late presentation can show a wide AG with a deceptively normal osmolar gap. Order both early and trend.
Fomepizole + emergent dialysis (lower threshold than EG: pH < 7.30 or any visual changes). Folinic acid 50 mg IV q4h enhances formate clearance.
Isopropanol
Rubbing alcohol, hand sanitizer
Acetone (NOT an acid)
Osmolar gap WITHOUT AGMA, ketones positive without acidosis, fruity breath, CNS depression. Mimics DKA but glucose normal.
Supportive only. Fomepizole NOT indicated (no toxic acid metabolite). Dialysis only if hemodynamic instability or coma.
Propylene glycol
IV solvent in lorazepam, phenobarbital, diazepam infusions
Lactic acid (Type B lactic acidosis)
ICU patient on prolonged benzo drip with rising lactate without hypoperfusion. AKI possible.
Stop the offending infusion. Fomepizole if severe. Dialysis for refractory cases.
When to give fomepizole empirically: Suspected toxic alcohol ingestion + any of (osmolar gap > 10, pH < 7.30, AG > 16, visual changes, AKI). Don't wait for the level. Fomepizole blocks alcohol dehydrogenase, halting metabolism to the toxic acid. Loading dose 15 mg/kg IV over 30 min. Ethanol drip is the fallback when fomepizole is unavailable (target ethanol level 100–150 mg/dL).
Respiratory Acidosis (PaCO2 > 40)
Hypoventilation fails to clear CO2. Acute (HCO3 rises 1 per 10 mmHg ↑ PaCO2) vs chronic (HCO3 rises 3.5 per 10) distinction matters: chronic is renally compensated, acute is dangerous and may need ventilation.
Check vent settings before treating the patient. Always.
Acute vs chronic at the bedside: Pure acute respiratory acidosis means HCO3 ≈ 24 + (PaCO2 − 40)/10. If HCO3 is much higher than predicted, the kidneys have had days to compensate (chronic). A COPD patient with pH 7.36, PaCO2 65, HCO3 36 is at chronic baseline; the same numbers in a previously healthy patient mean impending failure.
Respiratory Alkalosis (PaCO2 < 40)
Hyperventilation. Almost always centrally driven. Most common acid-base disorder in hospitalized patients, and frequently part of a mixed picture (sepsis, salicylates, hepatic encephalopathy).
Trigger
Mechanism / Notes
Hypoxemia
Carotid body drives ventilation. PE, pneumonia, pulmonary edema, high altitude, severe anemia. Always check SpO2 and consider CTPA in unexplained tachypnea.
Sepsis
Cytokine-mediated central drive. Often the earliest acid-base abnormality, before lactate or hypotension appear.
Pain / anxiety
Voluntary or involuntary hyperventilation. Pure psychogenic hyperventilation is a diagnosis of exclusion (rule out PE, sepsis, ASA first).
Salicylate toxicity
Direct medullary stimulation + uncoupling of oxidative phosphorylation. Classic mixed AGMA + respiratory alkalosis. Tinnitus is the giveaway.
Hepatic encephalopathy / cirrhosis
Ammonia and progesterone-like metabolites stimulate the medullary center. Almost universal in advanced cirrhosis.
Pregnancy
Progesterone is a respiratory stimulant. Normal pregnant PaCO2 is 28–32 with compensatory low HCO3 (~18–20).
CNS lesions
Brainstem stroke, tumor, infection, head injury → central neurogenic hyperventilation.
Iatrogenic
Over-ventilation on the vent (rate or tidal volume too high). Re-check settings before treating.
Compensation rule: Acute → HCO3 drops 2 per 10 mmHg ↓ PaCO2. Chronic → HCO3 drops 5 per 10. So a chronic respiratory alkalosis can present with a markedly low HCO3 (15–18) that mimics metabolic acidosis. Always check the pH first; alkalemia rules out a primary metabolic acidosis.
🧪 Workup
Workup
ABG/VBG -VBG acceptable for pH/HCO₃
BMP -AG calculation
Albumin -corrected AG = AG + 2.5×(4−albumin)
Lactate -#1 AG acidosis in hospital
Ketones/BHB
Osmolality (serum + calculated) -osmol gap >10 = toxic alcohol
Urine AG -positive=RTA, negative=GI loss
APAP + salicylate -always in unexplained AG acidosis
🚨 Management
Management
AG acidosis: DKA→insulin. Lactic→treat shock. Toxic alcohols→fomepizole+dialysis. Uremia→dialysis. Stewart Approach, Kellum 2009
Non-AG acidosis: Diarrhea→IVF. RTA→bicarb. NS-induced→switch to LR.
Albumin is a negatively charged protein that contributes ~12 mEq/L to the unmeasured anions (the normal AG). In hypoalbuminemic patients (cirrhosis, nephrotic syndrome, malnutrition, critical illness), the baseline AG is lower because there are fewer albumin anions. A "normal" AG of 12 in a patient with albumin of 2 actually represents a hidden AG elevation of ~5. Correction: for every 1 g/dL albumin below 4, add 2.5 to the calculated AG.
Walk me through the 5-step approach to ABG interpretation.
Step 1: Look at pH -acidemia (< 7.35) or alkalemia (> 7.45)? Step 2: Identify the primary disorder -does the pCO₂ explain it (respiratory) or the HCO₃ (metabolic)? Step 3: Is compensation appropriate? For metabolic acidosis: Winter's formula (expected pCO₂ = 1.5 × HCO₃ + 8 ± 2). If actual pCO₂ is HIGHER than expected → concurrent respiratory acidosis. If LOWER → concurrent respiratory alkalosis.
How do you calculate the corrected anion gap for albumin?
The anion gap is falsely low in hypoalbuminemia (albumin is the main unmeasured anion). Corrected AG = Calculated AG + 2.5 × (4.0 − measured albumin). For each 1 g/dL drop in albumin below 4, add 2.5 to the AG. Example: Na 140, Cl 108, HCO₃ 20, albumin 2.0 → raw AG = 140-108-20 = 12 (looks normal). Corrected AG = 12 + 2.5 × (4.0-2.0) = 17 (elevated!). Without correction, you'd miss a significant anion gap acidosis.
How many types of lactic acidosis are there?
Two (Cohen-Woods): Type A = tissue hypoperfusion or hypoxia (shock, ischemia, severe hypoxemia, anemia, CO poisoning) and Type B = everything else. Type B has 3 subtypes: B1 underlying disease (liver failure, malignancy, sepsis, thiamine deficiency, short bowel/SIBO), B2 drugs/toxins (metformin, linezolid, propofol, NRTIs, β2 agonists), B3 inborn errors (mitochondrial, PDH deficiency).
Short bowel patient with episodic confusion and slurred speech after meals, wide anion gap, but lactate is normal. Diagnosis?
D-lactic acidosis from bacterial overgrowth. Gut bacteria (Lactobacillus, Strep bovis, Bifidobacterium) ferment unabsorbed carbs into D-lactate, which humans cannot clear (we only metabolize L-lactate efficiently). The standard lactate assay measures L-lactate only, so it reads normal despite the gap. Order D-lactate level to confirm. Treat: low-carb diet, oral non-absorbable antibiotics (metronidazole, neomycin, rifaximin). Cohen-Woods: Type B1.
Lactate is 8 but the patient is well-perfused, BP normal, no shock. What's on your differential?
Type B lactic acidosis. Think drugs (metformin/MALA, linezolid > 2 wks, propofol infusion syndrome, NRTIs, β2 agonists like albuterol or epinephrine), liver failure (impaired clearance), malignancy (Warburg effect, classic in leukemia/lymphoma), thiamine deficiency (especially alcoholics, refeeding), D-lactic acidosis in short bowel. Sepsis can also cause Type B physiology even before overt hypotension.
Clinical Examples
📋 Case 1, Triple Acid-Base Disorder in Sepsis
Patient: 58M with septic shock from pneumonia. ABG: pH 7.22, pCO₂ 30, HCO₃ 12. Na 142, Cl 98, albumin 2.0. Lactate 8.4. Also receiving NS resuscitation for 24h.
Triple disorder: AG metabolic acidosis (lactic from sepsis) + respiratory acidosis (respiratory failure) + metabolic alkalosis (contraction from volume depletion)
Address the lactate: aggressive IVF (switch to LR, NS worsens non-AG acidosis), source control, antibiotics
The rising pCO₂ suggests respiratory fatigue → may need intubation soon (normally sepsis causes hyperventilation/low pCO₂)
Correct the albumin, always use corrected AG in ICU patients (hypoalbuminemia is nearly universal)
Recheck ABG in 2h, if pCO₂ continues to rise, intubate before arrest
Teaching point: A "normal" pCO₂ in a septic patient is alarming, they should be hyperventilating. A pCO₂ that is higher than Winter's predicted suggests respiratory muscle fatigue and impending respiratory arrest. This is a pre-intubation sign.
📋 Case 2, Non-Anion Gap Metabolic Acidosis (NAGMA)
Patient: 45F with chronic diarrhea from Crohn's disease. pH 7.30, pCO₂ 28, HCO₃ 14. Na 138, Cl 112, AG 12 (normal). Urine: Na 30, K 20, Cl 60.
Key findings: Normal AG + metabolic acidosis = NAGMA (non-anion gap metabolic acidosis). Hyperchloremic (Cl elevated). Use urine anion gap (UAG) to distinguish GI vs renal cause: UAG = Na+K-Cl = 30+20-60 = -10 (NEGATIVE).
Management:
Negative UAG = kidneys ARE appropriately excreting acid (NH4⁺) → GI bicarbonate loss (diarrhea is the cause)
If UAG were positive: kidneys CANNOT excrete acid → renal tubular acidosis (RTA)
Treat the diarrhea: optimize Crohn's therapy (5-ASA, immunomodulators, biologics per GI)
Oral sodium bicarbonate 650 mg TID for symptomatic acidosis (bridge while treating diarrhea)
Replace potassium (diarrheal losses), hypokalemia is common with GI bicarbonate loss
Teaching point: The urine anion gap is the key to NAGMA workup. Negative UAG = GI loss (diarrhea, kidneys working fine). Positive UAG = renal problem (RTA, kidneys can't excrete acid). Remember: "Negative = Normal kidneys, Positive = Problem in kidney."
📋 Case 3, Mixed Metabolic Alkalosis + Respiratory Alkalosis
Patient: 72F with COPD on chronic steroids, admitted for COPD exacerbation with NG tube on suction × 3 days. ABG: pH 7.58, pCO₂ 32, HCO₃ 38. K⁺ 2.8, Cl 88.
Key findings: Severely alkalemic (pH 7.58, dangerous). Two alkalosis disorders: metabolic alkalosis (HCO₃ 38, from NG suction losing HCl + volume contraction) AND respiratory alkalosis (pCO₂ 32, should be 48-52 for this HCO₃ level as compensation, but is much lower → concurrent respiratory alkalosis from anxiety/pain).
Management:
Replace volume: NS is chloride-rich (restores renal ability to excrete bicarb, "chloride-responsive" metabolic alkalosis)
Replace potassium aggressively: K⁺ 2.8 is dangerous + hypokalemia maintains metabolic alkalosis (kidneys retain H⁺ to excrete K⁺)
Review NG suction necessity, can it be discontinued or placed to gravity?
Danger: pH > 7.55 causes seizures, arrhythmias, and shifts the oxygen dissociation curve left (impaired O₂ delivery)
Teaching point: Metabolic alkalosis is maintained by three things: volume depletion (kidneys reabsorb Na with HCO₃), hypokalemia (kidneys excrete H⁺ instead of K⁺), and chloride depletion. Fixing all three (NS + KCl) corrects "chloride-responsive" alkalosis. Urine Cl < 20 = chloride-responsive.
📣 Sample Presentation
One-Liner
"Mr. Young is a 32-year-old with type 1 DM presenting with ABG: pH 7.18, pCO₂ 22, HCO₃ 8. Na 140, Cl 102, AG 30. Consistent with anion gap metabolic acidosis with appropriate respiratory compensation."
Key Points to Cover on Rounds
5-step ABG: (1) Acidemia (pH 7.18), (2) Primary metabolic acidosis (low HCO₃ 8), (3) Respiratory compensation: expected pCO₂ by Winter's = 1.5(8)+8±2 = 18-22 → actual 22 (appropriate), (4) AG 30 (elevated, corrected for albumin). (5) Delta-delta: ΔAG=18, ΔHCO₃=16 → ratio 1.1 (pure AG acidosis). Etiology: DKA (glucose 420, ketones positive). No concurrent non-AG acidosis or metabolic alkalosis. Plan: treat DKA -insulin drip, fluids, electrolyte monitoring.
Monitoring
ABG q2-4h during correction
BMP q4-6h -K⁺ shifts with pH
AG trend
Lactate q2-4h if lactic acidosis
UOP
⚡ Summary
Summary
Work Every Gas the Same Way
Five steps in the same order every time: pH, primary disorder, compensation, anion gap, delta-delta.The discipline is the point: skipping straight to a pattern you recognize is how a second, hidden disorder gets missed in a patient who has three.
Steps 1 and 2
pH below 7.35 is acidemia, above 7.45 is alkalemia, and it names the primary disorder because compensation never fully corrects the pH. Then match the direction: a low pH with a low bicarbonate is metabolic acidosis, a low pH with a high pCO₂ is respiratory acidosis, and so on. A normal pH with abnormal numbers means two opposing disorders, not a normal patient.
Check Whether Compensation Fits
Metabolic acidosis: Winter's formula, expected pCO₂ = 1.5 × HCO₂ + 8 ± 2.Acute respiratory: bicarbonate moves 1 per 10 mmHg of CO₂; chronic: 4 per 10.Compensation outside the predicted range is a second primary disorder, and this is the step that finds the patient who is tiring toward respiratory failure while their metabolic acidosis is being treated.
Always Calculate the Anion Gap
Na minus Cl minus HCO₂, normal about 12.Correct it for albumin: add 2.5 for every 1 g/dL the albumin is below 4, because albumin is the main unmeasured anion. An uncorrected gap in a hypoalbuminemic patient hides a real gap acidosis, which is the commonest reason lactic acidosis and ketosis are missed in the sick and the malnourished.
Know the Two Cause Lists
MUDPILES for a raised gap: Methanol, Uremia, DKA, Propylene glycol, Isoniazid or Iron, Lactate, Ethylene glycol, Salicylates. HARDUPS for a normal gap: Hyperalimentation, Acetazolamide, RTA, Diarrhea, Ureteroenteric fistula, Pancreatic fistula, Saline. Diarrhea and RTA are the two that matter at the bedside, separated by the urine anion gap.
Delta-Delta Finds the Third Disorder
Compare the rise in anion gap with the fall in bicarbonate.A ratio near 1 is a pure gap acidosis. Below 1 means a coexisting non-gap acidosis. Above 2 means a coexisting metabolic alkalosis, classically the DKA patient who has also been vomiting. Skipping this step is how a mixed picture gets treated as a simple one.
Check the Osmolar Gap When the Gap Is Unexplained
A raised anion gap with an osmolar gap above 10 means a toxic alcohol: methanol, ethylene glycol or propylene glycol. Treat with fomepizole and dialysis, and do not wait for confirmatory levels, which are send-outs. Calcium oxalate crystals and acute kidney injury point to ethylene glycol; visual loss points to methanol.
Separate Type A From Type B Lactate
Type A is hypoperfusion, shock, ischemia or hypoxia, and it is the one that means the patient is dying. Type B has no perfusion deficit: metformin, alcohol, thiamine deficiency, malignancy, linezolid, propofol, epinephrine infusion. Treating a type B lactate with more fluid does nothing, so the mechanism has to be identified before the number is chased. Also remember the ABG is only one input: correlate it with the patient in front of you.
RoundsRx Infographic Series · #10 · Renal & Metabolic · PDF 160 KB
Text version
Nephrology / Critical Care · One Pager
ABG Interpretation
5 steps: pH → primary disorder → compensation → AG (corrected for albumin) → delta-delta. MUDPILES for AG acidosis. Winter's formula.
🧪 5-Step Approach
(1) pH (acid vs alkalemia). (2) Primary disorder (pCO₂ vs HCO₃). (3) Compensation appropriate? (Winter's formula for met acidosis). (4) AG corrected for albumin. (5) Delta-delta (ΔAG/ΔHCO₃).
🚨 AG Acidosis -MUDPILES
M ethanol · U remia · D KA · P ropylene glycol · I NH/Iron · L actic acidosis · E thylene glycol · S alicylates Check lactate, ketones, osmol gap, tox screen.
💊 Key Formulas
Winter's: expected pCO₂ = 1.5 × HCO₃ + 8 ± 2. AG = Na − Cl − HCO₃. Corrected AG = AG + 2.5 × (4 − albumin). Delta-delta: > 2 = hidden met alk, < 1 = hidden non-AG met acidosis.
💊 Key Drugs
Bicarb drip150 mEq in D5W (if pH < 6.9 in DKA)
Fomepizole15 mg/kg load (toxic alcohols)
Insulin drip0.1 u/kg/hr (DKA)
DialysisRefractory acidosis or toxic ingestion
⚠️ Pitfalls
Not correcting AG for albumin (misses hidden AG acidosis in ICU patients)
Know when to call nephrology emergently (AEIOU) and the differences between HD, CRRT, and PD. The decision to start emergent dialysis is clinical, not based on a single lab value.
🔍 Emergent Indications -AEIOU
AEIOU -Emergent dialysis indications (refractory to medical management):
Letter
Indication
Details
A
Acidosis
Severe metabolic acidosis (pH < 7.1) refractory to bicarb. Especially toxic ingestions (methanol, ethylene glycol -dialysis removes the toxin AND corrects acidosis).
E
Electrolytes
Refractory hyperkalemia not responding to medical management (calcium, insulin/glucose, albuterol, bicarb). K⁺ > 6.5 with ECG changes + anuric patient → emergent HD.
I
Ingestion
Toxic alcohols (methanol, ethylene glycol), lithium, salicylate, theophylline, metformin (with severe lactic acidosis). Dialysis removes the toxin directly.
O
Overload (volume)
Pulmonary edema refractory to diuretics. Anuric patient with flash pulmonary edema → emergent ultrafiltration/HD.
U
Uremia
Uremic symptoms: encephalopathy (AMS, asterixis), pericarditis (friction rub → can progress to tamponade), uremic bleeding (platelet dysfunction), intractable nausea/vomiting. Uremic pericarditis = absolute indication -can cause fatal tamponade.
There is no specific BUN or Cr threshold for starting dialysis.IDEAL, 2010: early initiation (GFR 10–14) showed no survival benefit over late initiation (GFR 5–7) in CKD. The decision is based on clinical symptoms and refractory complications, not a single lab value. A patient with BUN 150 and no symptoms doesn't need dialysis. A patient with BUN 80 and uremic pericarditis does.
🔧 Modalities
HD vs CRRT vs PD
Feature
Intermittent HD
CRRT
PD
Setting
Outpatient dialysis center, inpatient
ICU only
Home (chronic) or inpatient
Access
AV fistula, AV graft, or dialysis catheter (IJ preferred)
Dialysis catheter (large bore, dual lumen)
PD catheter (Tenckhoff, peritoneal)
Duration
3–4 hours, 3×/week
Continuous (24/7)
Overnight (APD) or 4× daily exchanges (CAPD)
Hemodynamic stability
Rapid fluid/solute shifts → hypotension risk
Gentler -preferred for hemodynamically unstable patients (septic shock, cardiogenic shock)
Gentle, minimal hemodynamic effects
Solute clearance
Fast, efficient for small molecules
Slower per hour but continuous → equivalent over 24h
ICU patients who are hemodynamically unstable. AKI in shock. Cerebral edema (slower osmolar shifts).
Chronic CKD/ESKD who want home-based therapy. Preserve residual renal function longer.
CRRT Modes
Mode
Mechanism
Use
CVVH (Continuous VenoVenous Hemofiltration)
Convection (hydrostatic pressure pushes fluid + solutes across membrane, replaced with clean fluid)
Volume overload, middle-molecule clearance
CVVHD (Continuous VenoVenous Hemodialysis)
Diffusion (solute moves down concentration gradient across membrane via dialysate)
Small molecule clearance (urea, K⁺, toxins)
CVVHDF (Continuous VenoVenous Hemodiafiltration)
Both convection + diffusion
Most commonly used in ICU. Combines benefits of both. Best overall solute + fluid clearance.
Vascular Access
AV fistula -gold standard for chronic HD. Lowest infection rate, longest patency. Place when eGFR ~20 (needs 2–3 months to mature). Radiocephalic (wrist) → brachiocephalic (upper arm).
AV graft -synthetic conduit. Can use in 2–3 weeks. Higher infection and thrombosis rate than fistula.
Tunneled dialysis catheter (Permacath) -for patients awaiting fistula maturation or not candidates for fistula. Highest infection rate. Right IJ preferred (straightest path to RA).
Non-tunneled temporary catheter -emergent dialysis only. IJ or femoral. Should be replaced within 1–2 weeks.
Preserve arm veins: avoid blood draws and IVs in the non-dominant arm of any patient with CKD stage 3+ or approaching dialysis. That arm may be needed for a fistula. Never use a dialysis catheter for non-dialysis purposes (blood draws, meds, fluids) unless absolute emergency -infection risk.
IDH prevention: slow UF, cool dialysate 35.5°C, midodrine, hold antihypertensives HD days
💊 Medications
Medications -Dialysis
Drug (Brand)
Dose
Route
Indication
Notes
CIRCUIT ANTICOAGULATION
Heparin
Per protocol (bolus + infusion)
IV
HD circuit anticoagulation
Standard for intermittent HD. Monitor aPTT. Hold if active bleeding -run without anticoag.
Citrate (regional)
Per CRRT protocol
IV
CRRT anticoagulation
Preferred for CRRT -chelates calcium in circuit. Monitor ionized calcium closely (systemic and circuit). Risk: metabolic alkalosis, hypocalcemia.
CKD-MBD MANAGEMENT
Sevelamer (Renvela)
800–1600 mg with meals
PO
Phosphate binder
Non-calcium binder -preferred to avoid vascular calcification. Take with every meal.
Calcium acetate (PhosLo)
667 mg (1–2 tabs) with meals
PO
Phosphate binder
Calcium-based binder. Avoid if hypercalcemic or high Ca x PO4 product.
Cinacalcet (Sensipar)
30–180 mg PO daily
PO
Secondary hyperparathyroidism
Calcimimetic -activates CaSR on parathyroid → suppresses PTH. GI side effects common. For dialysis patients with refractory hyperPTH.
Calcitriol (Rocaltrol)
0.25–0.5 mcg PO daily
PO
Active vitamin D
For secondary hyperPTH. Monitor calcium (risk of hypercalcemia). Alternative: paricalcitol (Zemplar).
ANEMIA MANAGEMENT
Epoetin alfa (Procrit)
50–300 units/kg 3x/week
IV/SQ
Anemia of CKD/ESKD
Iron-replete first (ferritin > 200, TSAT > 20%). Target Hgb 10–11.5. Never > 13.
Darbepoetin (Aranesp)
0.45 mcg/kg q2 weeks or monthly
IV/SQ
Anemia of CKD/ESKD
Long-acting ESA -less frequent dosing. Same Hgb target.
Iron sucrose (Venofer)
100–200 mg IV per HD session
IV
Iron deficiency on dialysis
Given during HD sessions. Target ferritin 200–500, TSAT 20–30%. Must replete iron before starting ESA.
📋 On Rounds
When do you choose CRRT over intermittent HD in the ICU?
Hemodynamic instability is the primary indication for CRRT over HD. Intermittent HD removes fluid and solutes rapidly over 3–4 hours → large intravascular volume shifts → hypotension (especially in patients already on vasopressors). CRRT removes the same total fluid/solutes but continuously over 24 hours → gentler osmolar and volume shifts → better tolerated hemodynamically.
Why is uremic pericarditis an absolute dialysis indication?
Uremic pericarditis is a fibrinous/hemorrhagic pericarditis caused by uremic toxin accumulation irritating the pericardium. Unlike viral pericarditis, it can rapidly progress to hemorrhagic pericardial effusion → tamponade because uremic patients have concurrent platelet dysfunction (uremic bleeding). The pericarditis responds to intensive dialysis (daily HD for 1–2 weeks), not to NSAIDs or colchicine (which treat viral pericarditis).
A patient on HD has hypotension during the session. What do you do?
Intradialytic hypotension (IDH) -the most common HD complication (~20-30% of sessions). Immediate management: (1) Passive leg raise (Trendelenburg has no evidence), (2) Reduce UF rate or stop UF (keep dialysis running for clearance), (3) NS 100-250 mL bolus, (4) If persistent → stop dialysis.
What is the difference between intermittent HD and CRRT, and when do you choose each?
Calcium gluconate 3g IV over 5 min (membrane stabilizer, buys time, does NOT lower K⁺)
Insulin 10 units IV + D50 1 amp (shifts K⁺ intracellularly, onset 15 min, lasts 4-6h)
Emergent hemodialysis, call nephrology and dialysis nurse STAT. Most effective K⁺ removal
Albuterol 10-20 mg nebulized (shifts K⁺, additive to insulin)
Kayexalate is NOT emergent therapy (onset 6-12h, causes GI necrosis risk)
Teaching point: The order matters: stabilize the membrane (calcium) → shift K⁺ (insulin/albuterol) → remove K⁺ (dialysis). Calcium gluconate does not lower potassium, it prevents cardiac arrest while you arrange definitive removal.
📋 Case 2, CRRT in ICU for Septic Shock + AKI
Patient: 67F in ICU with septic shock on norepinephrine 0.25 mcg/kg/min. Oliguric AKI (Cr 1.1 → 5.8 in 3 days). K⁺ 5.9, pH 7.18, HCO₃ 12. Volume overloaded (6L positive).
Key findings: AKI with multiple dialysis indications (acidosis, hyperkalemia, volume overload) but hemodynamically unstable, cannot tolerate intermittent HD (rapid fluid shifts → hypotension).
Management:
CRRT (continuous venovenous hemodiafiltration, CVVHDF) rather than intermittent HD
CRRT advantages in shock: slow continuous fluid removal (50-100 mL/hr net UF), hemodynamically gentle
Dialysis catheter: temporary non-tunneled in right IJ (preferred site for flow)
Anticoagulation for CRRT circuit: citrate regional anticoagulation (preferred) or heparin
Monitor ionized calcium closely if using citrate (citrate chelates calcium → hypocalcemia risk)
Teaching point: CRRT is not "better" than intermittent HD, it's gentler. The AKIKI trial showed no mortality benefit for early vs delayed RRT initiation in ICU. Start CRRT for absolute indications (AEIOU), not prophylactically.
📋 Case 3, Dialysis Access Complications
Patient: 52M on HD via left brachiocephalic AV fistula × 3 years. Presents with left arm swelling, difficulty cannulating the fistula, and prolonged bleeding after last HD session. Thrill diminished on exam.
Key findings: AV fistula stenosis with signs of access failure: diminished thrill (should be palpable), prolonged bleeding (elevated venous pressure), difficult cannulation, arm edema (central venous stenosis).
Management:
Duplex ultrasound of fistula to confirm stenosis location and degree
Fistulogram (contrast venography) with angioplasty if stenosis > 50% with clinical symptoms
If angioplasty fails: surgical revision or new access creation
Temporary dialysis catheter if fistula nonfunctional and dialysis cannot wait
AV fistula hierarchy: radiocephalic (wrist) → brachiocephalic → brachiobasilic transposition → AV graft → tunneled catheter (last resort)
Teaching point: AV fistula is the gold standard for HD access (lowest infection rate, longest patency). Fistula first, always plan access early (6 months before anticipated HD start for fistula maturation). Catheters should be a bridge, not permanent.
📣 Sample Presentation
One-Liner
"Mrs. White is a 62-year-old with ESKD on HD (MWF via LUE AV fistula) who missed 2 sessions, presenting with dyspnea, bilateral crackles, K⁺ 6.8, and BUN 112."
Key Points to Cover on Rounds
Missed dialysis ×2 → volume overload + hyperkalemia + uremia. K⁺ 6.8 with peaked T waves → calcium gluconate, insulin/D50, albuterol given. Nephrology emergently contacted -urgent HD session arranged. Access: LUE fistula with good thrill and bruit. Fluid overloaded: JVP 14 cm, crackles bilaterally, 3+ LE edema. UF goal 4L for this session. Plan: resume regular MWF HD, social work to address barriers to sessions.
Monitoring -Dialysis
Parameter
Frequency
Target / Action
Pre/post BUN, K+, bicarb, Ca, PO4
Each HD session (or daily for CRRT)
Assess clearance adequacy. Post-HD K+ should be 3.5–5.0. Bicarb > 22. PO4 3.5–5.5.
Check thrill and bruit -absence suggests thrombosis or stenosis. Inspect for signs of infection, aneurysm, steal syndrome (cold/pale hand).
Kt/V
Monthly
Dialysis adequacy: target Kt/V ≥ 1.4 (single-pool) for thrice-weekly HD. URR (urea reduction ratio) > 65% is alternative measure.
Hgb / iron studies
Monthly
Hgb target 10–11.5 g/dL. Ferritin 200–500, TSAT 20–30%. Replete iron before adjusting ESA dose.
PTH
Every 3 months
Target 2–9x upper limit of normal for dialysis patients. Rising PTH → increase phosphate binders, add cinacalcet or calcitriol.
Access is lifeline. Protect AV fistulas -no blood draws, no BPs, no IVs in the fistula arm. Never use a dialysis catheter for non-dialysis purposes unless absolute emergency.
⚡ Summary
Summary
AEIOU Is the Emergent Indication List
Acidosis refractory to medical therapy, Electrolytes (refractory hyperkalemia), Intoxications (methanol, ethylene glycol, lithium, salicylates, metformin), Overload refractory to diuretics, Uremia with pericarditis, encephalopathy or bleeding. Refractory is the operative word in every one of them.
There Is No BUN or Creatinine Threshold
The decision is clinical.IDEAL showed early initiation at GFR 10 to 14 gave no survival benefit over late initiation at 5 to 7, and in AKI, AKIKI and STARRT-AKI showed a watchful strategy is safe and avoids dialysis altogether in about half. Dialyzing a number rather than a patient exposes them to access complications and hypotension for nothing.
Choose the Modality by Hemodynamics
Intermittent hemodialysis: efficient, 3 to 4 h, for the hemodynamically stable, and the fastest way to clear potassium or a dialyzable toxin.CRRT: continuous and gentle, for the hemodynamically unstable patient on vasopressors, and for cerebral edema or acute liver failure where rapid osmolar shifts are dangerous.Peritoneal dialysis: no vascular access or anticoagulation needed, but slower and unsuitable after recent abdominal surgery.
CRRT Is Not Better, Just Gentler
It has not been shown to improve survival or renal recovery over intermittent hemodialysis. Its advantage is tolerability in shock, and its costs are immobility, continuous anticoagulation, and the frequent drug dose errors that follow from a clearance nobody has recalculated. Review every drug dose whenever the modality changes.
Know the CRRT Modes
CVVH uses convection (solute dragged with fluid) and clears middle molecules better.CVVHD uses diffusion across a concentration gradient and clears small solutes.CVVHDF combines both. The practical difference is modest; the important thing is knowing which is running so the prescription and the drug dosing match.
Match the Access to the Timeframe
A non-tunneled temporary catheter for immediate need, tunneled for weeks to months, and an arteriovenous fistula for long-term dialysis.A fistula takes months to mature, which is why access planning starts at CKD stage 4. Fistula beats graft beats catheter for infection and patency, and catheter-related bacteremia is a major cause of death in dialysis patients.
Protect the Veins Before They Are Needed
Avoid PICC lines, subclavian catheters and unnecessary phlebotomy in the non-dominant arm of any advanced CKD patient. A PICC placed for convenience can permanently destroy the vessel that would have carried a fistula, and this decision is usually made by someone who has never met the nephrologist.
Anticipate the Complications
Intradialytic hypotension is the commonest, from removing fluid faster than it refills from the interstitium. Dialysis disequilibrium syndrome, headache, confusion and seizures from rapid urea clearance causing cerebral edema, which is why the first sessions in a very uremic patient are deliberately short and gentle. Also watch for arrhythmia from potassium shifts, bleeding from anticoagulation, and access infection.
Painful violaceous skin necrosis from calcified arterioles in ESRD patients. 1-year mortality 45–80%, mostly from sepsis. Treatment is a coordinated package: sodium thiosulfate, stop the calcifying drugs (warfarin, Ca binders), aggressive phosphate control, and don't over-debride.
🔍 Overview
Definition
Calciphylaxis (preferred current name: calcific uremic arteriolopathy, CUA) is a small-vessel vasculopathy with medial calcification, intimal proliferation, and thrombosis of dermal/subcutaneous arterioles → ischemic skin necrosis with painful violaceous lesions that progress to non-healing ulcers and eschars. Sepsis from infected ulcers is the most common cause of death.
Epidemiology
1–4% of dialysis patients per year (US registry data); higher in obese, diabetic, female ESRD patients.
Female: male ratio ~3:1.
Predominantly in ESRD on dialysis (~80–90% of cases). Non-uremic calciphylaxis exists but is rare (primary HPT, malignancy, autoimmune disease, alcoholic liver disease).
Mean age ~55–60 years.
1-year mortality: ~45–55% overall; ~80% if central (truncal) lesions, ~50% if distal only.
Pathophysiology
Calciphylaxis is not just "high Ca × P precipitating in skin." It is an active, regulated process: vascular smooth muscle cells trans-differentiate into osteoblast-like cells and lay down hydroxyapatite in arteriolar media. Loss of natural calcification inhibitors drives this process.
Matrix Gla protein (MGP) is the body's main vascular calcification inhibitor. It requires vitamin K-dependent γ-carboxylation to be active. Warfarin blocks this (the same mechanism that gives it anticoagulant effect against factors II/VII/IX/X), leaving uncarboxylated, inactive MGP and unleashing arterial calcification. This is why warfarin is a major risk factor.
Fetuin-A, another circulating calcification inhibitor, is depleted in chronic inflammation and uremia.
Hyperphosphatemia directly drives smooth-muscle osteoblast differentiation through the Pit-1 phosphate transporter.
Ca × P (mg²/dL²) = Total Ca (mg/dL) × Phosphate (mg/dL)
Target in dialysis patients: < 55 mg²/dL². Above ~55–70, passive precipitation of hydroxyapatite in soft tissue becomes thermodynamically favorable (this approximates the solubility product constant for CaPO₄ under physiologic conditions). Use albumin-corrected Ca, total Ca underestimates ionized Ca in hypoalbuminemia (common in ESRD): corrected Ca = total Ca + 0.8 × (4 − albumin).
Worked example (Case 1 from Rounds tab): Ca 9.8, P 6.4 → Ca × P = 9.8 × 6.4 = 62.7 mg²/dL², above the < 55 target → drives both passive and active calcification.
KDIGO 2017 caveat: the current CKD-MBD guideline moved away from rigid Ca × P targets because (1) single time-point calculations are unreliable (P fluctuates with meals and dialysis), and (2) the dominant biology is active vascular calcification (matrix Gla protein loss, BMP-2 upregulation, smooth-muscle osteoblast trans-differentiation), not just passive precipitation. Use Ca × P as a bedside check but treat Ca, P, and PTH individually. In calciphylaxis specifically, the product is still clinically useful because passive precipitation does matter at scale here.
Risk Factors (Modifiable First, Targets for Treatment)
Risk Factor
Mechanism
Modifiable?
Warfarin use
Blocks vitamin K-dependent activation of matrix Gla protein → unleashes vascular calcification
Hypercoagulable states (protein C/S deficiency, antiphospholipid)
Promotes microthrombosis in already-calcified vessels
PARTIAL Treat underlying
Clinical Presentation
Painful (severe, opioid-requiring, often disproportionate to lesion size, this is the single most useful clinical pearl). Pain often precedes visible skin findings by days.
Violaceous retiform purpura (net-like / livedo-like pattern) → indurated tender plaques → necrotic eschar with surrounding violaceous halo → ulceration with thick black eschar.
Two distribution patterns:
Central (proximal): trunk, abdomen, thighs, breasts, buttocks. Worse prognosis (1-year mortality ~80%). Often multiple, large lesions.
Lesions at SC injection sites (heparin, insulin) is a near-pathognomonic finding in dialysis patients.
Usually not febrile at presentation unless ulcers are infected; fever is a sepsis red flag, not a primary feature.
Differential Diagnosis
Mimic
Distinguishing Feature
Warfarin-induced skin necrosis
Onset days 3–10 of warfarin, protein C deficiency, breasts/buttocks/extremities, NO ESRD context required. Histology: thrombi without medial calcification.
Cellulitis / necrotizing fasciitis
Fever, leukocytosis, more diffuse erythema, lacks the retiform livedo pattern. Necrotizing fasciitis spreads fast in hours.
Atheroembolic disease (cholesterol emboli)
Recent vascular procedure, livedo + blue toes + eosinophilia + ↓ complement. Usually distal.
Pustule → ulcer with violaceous undermined edge, IBD/RA association, pathergy (lesion at trauma sites).
Nephrogenic systemic fibrosis
Gadolinium exposure in advanced CKD, woody indurated plaques on extremities, NOT painful necrosis.
Oxalate vasculopathy
Primary hyperoxaluria or short bowel; calcium oxalate in tissue (not phosphate). Rare.
🧪 Workup
Diagnosis Is Often Clinical
In a dialysis patient with painful violaceous retiform lesions on adipose-rich areas, calciphylaxis is the diagnosis until proven otherwise. Definitive confirmation requires biopsy, but biopsy itself can extend the lesion and become a non-healing ulcer, so many centers treat empirically when the clinical picture is classic.
Laboratory Workup
Ionized Ca, phosphate, PTH, 25-OH vitamin D, ALP, albumin: characterize the CKD-MBD axis. Look for high P, high Ca, high PTH, high Ca × P product.
BMP, CBC: baseline.
INR, PT, aPTT: especially if patient on warfarin (which is a major modifiable risk factor).
Hypercoagulability workup if young, recurrent, or thrombotic features: protein C and S, antithrombin, factor V Leiden, antiphospholipid antibodies.
Vitamin K status: PIVKA-II (proteins induced by vitamin K absence/antagonist) if available; otherwise empiric supplementation if on warfarin or poor intake.
Wound cultures: if ulcerated, especially if febrile or systemic signs. Sepsis from infected ulcers is the leading cause of death.
Bone scan (Tc-99m bisphosphonate): subcutaneous radiotracer uptake at lesion sites. Sensitivity ~90%, useful when biopsy is too risky. Helpful to confirm diagnosis non-invasively.
CT: shows extent of subcutaneous calcification but adds radiation and contrast risk.
Skin Biopsy (Confirmatory but Risky)
Biopsy is the gold standard but controversial. The biopsy site can become a new non-healing ulcer in this hypercoagulable, ischemic skin. Reserve biopsy for cases where the diagnosis is genuinely unclear (atypical presentation, non-dialysis patient, mimics not excluded). For classic ESRD presentation, many centers skip biopsy and treat empirically.
Histology: medial calcification of small/medium dermal arterioles (von Kossa or Alizarin red stain), intimal proliferation, vascular thrombosis, panniculitis with fat necrosis.
Use punch biopsy from edge of lesion (not center, where necrosis obscures findings).
Avoid biopsying through ulcerated tissue.
🚨 Management
Treatment Is a Coordinated Package, Not a Single Drug
Mortality is 45–80% at 1 year, mostly from sepsis from infected ulcers. No single intervention fixes calciphylaxis. The strategy is to remove all calcification drivers simultaneously, deliver targeted therapy (sodium thiosulfate), and prevent infection. Multidisciplinary team: nephrology, dermatology, wound care, palliative care, surgery as needed.
Step-by-Step Management
Step
Intervention
Why It Matters
1. Sodium thiosulfate (STS)
Sodium thiosulfate 25 g IV over 30–60 min after each HD session (3×/week), continue 3–6 months minimum, often longer until healing
The cornerstone targeted therapy. Chelates calcium → soluble Ca-thiosulfate complex (cleared by dialysis), antioxidant, vasodilator (NO donor). Evidence: large case series (highest-quality available; no RCT). Side effects: metabolic acidosis (anion gap, treat with bicarb), nausea, hypotension, fluid overload. Reduce dose if these are intolerable.
2. Stop warfarin
Switch to apixaban (Eliquis) 2.5–5 mg BID if anticoagulation is still needed
Warfarin inhibits γ-carboxylation of matrix Gla protein, the body's main vascular calcification inhibitor → unleashes calcification. Apixaban does not affect MGP. KDIGO 2017 endorses avoiding warfarin in calciphylaxis. If anticoagulation can be stopped entirely (e.g., AF with low CHA₂DS₂-VASc), do so.
3. Stop calcium-based phosphate binders
Switch to non-calcium binder: sevelamer (Renvela), lanthanum (Fosrenol), ferric citrate (Auryxia), or sucroferric oxyhydroxide (Velphoro)
Calcium carbonate and calcium acetate add to systemic calcium load and Ca × P product. Non-Ca binders lower phosphate without driving calcification.
4. Aggressive phosphate control
Target P < 5.5 mg/dL, Ca × P product < 55. Strict 800–1000 mg/day dietary P. Intensify dialysis (longer sessions, more frequent, low-Ca dialysate 2.0–2.5 mEq/L)
Hyperphosphatemia drives smooth-muscle osteoblast differentiation via Pit-1 transporter. Removing the phosphate driver is essential. Low-Ca dialysate avoids adding calcium during the very treatment that should be removing it.
5. Hyperparathyroidism control
Cinacalcet (Sensipar) 30–180 mg PO daily (titrate to PTH 150–300) or etelcalcetide (Parsabiv) 5–15 mg IV after each HD. Refractory: parathyroidectomy
Calcimimetics activate the parathyroid Ca-sensing receptor → ↓ PTH → ↓ bone Ca and P efflux. Lower Ca, P, and PTH simultaneously, ideal for CUA. Parathyroidectomy reserved for medically refractory severe HPT (PTH > 800–1000 with hypercalcemia).
6. Vitamin K supplementation
Vitamin K1 (phytonadione) 1–10 mg PO daily
Activates matrix Gla protein (the natural calcification inhibitor). Most ESRD patients are functionally K-deficient. Especially important if recently on warfarin. Small RCTs (VitaVasK, others) suggest reduction in vascular calcification. Cheap, low-risk.
7. Wound care, conservative
Sterile non-adherent dressings, gentle cleansing. Avoid aggressive surgical debridement unless infected/septic; lesions can extend and become non-healing
The skin is ischemic; cutting healthy-looking edges propagates the lesion. Debride only frankly necrotic, infected tissue. Wound-care nursing service is invaluable.
8. Pain control
Multimodal: opioids (often required), gabapentin or pregabalin for neuropathic component, ketamine drip in severe cases, regional blocks. Avoid fentanyl patches over lesions
Pain is severe and opioid-requiring. Fentanyl patches absorb erratically over necrotic skin, and the patch's heat further worsens local ischemia. Opioids are dialyzable variably (avoid morphine in ESRD; hydromorphone, fentanyl IV, methadone are options).
9. Infection prevention & treatment
Low threshold for blood cultures and broad-spectrum antibiotics if febrile or systemic signs. Cover MRSA + Gram-negatives (vancomycin + cefepime or piperacillin-tazobactam, dose-adjusted for ESRD)
Sepsis from infected ulcers is the #1 cause of death. Don't wait for classic SIRS criteria; ESRD patients mount blunted febrile responses.
10. Hyperbaric oxygen (HBOT)ADJUNCT
2.0–2.4 ATA × 90 min, 5 days/week × 20–40 sessions
Increases tissue oxygen delivery, promotes angiogenesis, antimicrobial. Case series show benefit; not RCT-proven. Consider for severe or refractory cases at centers with HBOT expertise.
11. BisphosphonatesCASE-SERIES ONLY
Pamidronate 30–90 mg IV every 4–8 weeks
Inhibits osteoclast-mediated Ca/P efflux from bone; possibly direct effect on vascular calcification. Evidence weak (case series). Not first-line; consider in refractory cases or when STS is contraindicated.
12. Palliative care
Early integration, especially for severe/proximal disease
Mortality is high, pain is severe, and quality-of-life conversations are essential. Palliative care is not "giving up", it is good care.
What NOT to Do
Don't continue warfarin if there is any reasonable alternative (apixaban, no anticoagulation).
Don't aggressively debride non-infected lesions; the skin is ischemic and debridement extends necrosis.
Don't use IV calcium for hypocalcemia unless symptomatic and severe; binds to phosphate → CaPO₄ precipitation worsens calciphylaxis.
Don't use fentanyl patches over or near lesions.
Don't use gadolinium MRI contrast in advanced CKD/ESRD without weighing NSF risk.
Don't dismiss "bruise-like" pain in a dialysis patient as soft-tissue injury, painful retiform purpura is calciphylaxis until proven otherwise.
💊 Medications
Medications Reference
Drug
Dose
Role
Key Notes & Why It Matters
Sodium thiosulfate CORNERSTONE
25 g IV over 30–60 min after each HD session (3×/week)
Targeted therapy
Chelates Ca, antioxidant, vasodilator. Side effects: anion-gap metabolic acidosis (treat with bicarb), nausea, hypotension, volume overload. Reduce to 12.5 g if poorly tolerated. Continue 3–6+ months until healing.
Apixaban (Eliquis)
2.5–5 mg PO BID
Anticoagulation if needed (replace warfarin)
Does not inhibit matrix Gla protein. Preferred over warfarin in calciphylaxis when anticoagulation is needed. Dose-adjust per ESRD: 2.5 mg BID if 2 of (age ≥ 80, weight ≤ 60 kg, Cr ≥ 1.5).
Sevelamer (Renvela)
800–1600 mg TID with meals
Non-Ca phosphate binder
Polymeric, non-absorbed, no calcium load. Side effects: GI upset, metabolic acidosis. Less effective per-tablet than Ca-based binders (more pill burden).
Lanthanum (Fosrenol)
500–1000 mg TID chewed with meals
Non-Ca phosphate binder
Effective at lower pill burden than sevelamer. Side effects: GI upset. Long-term tissue accumulation (theoretical concern, not clinically validated).
Ferric citrate (Auryxia)
2 tablets (210 mg elemental Fe each) TID with meals
Non-Ca phosphate binder + iron source
Bonus iron repletion useful in CKD-related anemia. Side effects: dark stools, GI upset. Monitor ferritin and TSAT (avoid iron overload).
Sucroferric oxyhydroxide (Velphoro)
500 mg (1 tab) TID chewed with meals
Non-Ca phosphate binder
Lowest pill burden of the iron-based binders. Minimal systemic iron absorption (vs ferric citrate). Side effects: dark stools, diarrhea.
Cinacalcet (Sensipar)
30 mg PO daily, titrate to 30–180 mg/day
Calcimimetic for hyperparathyroidism
Activates parathyroid Ca-sensing receptor → ↓ PTH, ↓ Ca, ↓ P. Side effects: hypocalcemia (most common, monitor weekly initially), nausea, vomiting.
Etelcalcetide (Parsabiv)
5 mg IV after each HD; titrate to 2.5–15 mg per session
Calcimimetic, IV alternative to cinacalcet
Better adherence than oral cinacalcet (given by dialysis nurse). Same hypocalcemia risk; monitor Ca closely.
Vitamin K1 (phytonadione)
1–10 mg PO daily
Activates matrix Gla protein
Inexpensive, low-risk. Especially useful after stopping warfarin. Avoid if patient still requires warfarin (defeats anticoagulation).
PamidronateADJUNCT
30–90 mg IV every 4–8 weeks
Bisphosphonate, weak evidence
Inhibits osteoclast-mediated bone resorption; may reduce vascular calcification. Side effects: hypocalcemia, osteonecrosis of jaw (rare), atypical femoral fractures. Renal dose-adjust.
Hydromorphone or methadone or fentanyl IV
Per pain protocol
Pain control
Avoid morphine in ESRD (active metabolite M6G accumulates → neurotoxicity). Avoid fentanyl patches over lesions (heat + necrotic skin). Methadone is dialyzable variably and safe in ESRD with care.
"Ms. Reyes is a 58-year-old woman with ESRD on hemodialysis × 6 years (DM and HTN nephropathy), atrial fibrillation on warfarin, and BMI 34, admitted with 2 weeks of severely painful, expanding violaceous lesions on her abdomen and bilateral thighs. Pain is 10/10, requires PCA hydromorphone. On exam, she has multiple violaceous retiform plaques on the lower abdomen and medial thighs with central black eschars and surrounding livedo, no fever. Labs: Ca 9.8, P 6.4, PTH 540, Ca × P 63, INR 2.4, ALP 180, albumin 3.0. Bone scan shows subcutaneous tracer uptake corresponding to lesions. We have made the clinical diagnosis of calciphylaxis, started sodium thiosulfate 25 g IV after each HD, switched warfarin to apixaban, switched calcium acetate to sevelamer, started cinacalcet 30 mg daily, vitamin K1 5 mg daily, and engaged wound care, palliative care, and dermatology."
Pimp Questions
Why is warfarin a major risk factor for calciphylaxis?
Warfarin inhibits vitamin K-dependent γ-carboxylation, which activates not only clotting factors II/VII/IX/X but also matrix Gla protein (MGP), the body's primary inhibitor of vascular calcification. Uncarboxylated MGP is inactive → vascular smooth muscle freely undergoes osteoblast-like trans-differentiation → arterial media calcify. This is why apixaban (a direct factor Xa inhibitor with no effect on MGP) is preferred when anticoagulation is needed in calciphylaxis.
What is the mechanism of sodium thiosulfate in calciphylaxis?
Three proposed mechanisms: (1) Calcium chelation: thiosulfate binds free calcium to form soluble calcium-thiosulfate complexes that are dialyzable. (2) Antioxidant: scavenges reactive oxygen species, reduces vascular smooth-muscle osteoblast differentiation. (3) Vasodilation: thiosulfate is metabolized to hydrogen sulfide and other NO-related species, improving microvascular perfusion. Standard dose 25 g IV after each HD; main side effects are anion-gap metabolic acidosis, nausea, and hypotension.
A dialysis patient has a painful violaceous lesion on the abdomen. What's the differential and how do you tell them apart?
Calciphylaxis (ESRD context, painful retiform purpura, adipose-rich sites), warfarin-induced skin necrosis (days 3–10 of warfarin, protein C deficiency, breasts/buttocks, lacks ESRD requirement), cellulitis (febrile, leukocytosis, more diffuse), cholesterol emboli (recent vascular procedure, livedo + blue toes + eosinophilia), pyoderma gangrenosum (pustule → ulcer with violaceous undermined edge, IBD/RA), vasculitis (systemic features, positive serologies). The pain out of proportion to lesion size + ESRD context strongly favors calciphylaxis.
Why is biopsy controversial in calciphylaxis?
Biopsy is the gold standard (medial calcification, intimal proliferation, microthrombi on von Kossa stain), but the biopsy site itself can become a new non-healing ulcer because the surrounding skin is ischemic and hypercoagulable. For classic ESRD presentations, many centers diagnose clinically (or with bone scan, sensitivity ~90%) and treat empirically. Reserve biopsy for atypical cases (non-uremic, unusual distribution, mimics not excluded). If you do biopsy, take a punch from the edge of the lesion, not the center.
What is the prognosis of calciphylaxis?
Grim. 1-year mortality 45–80%. The leading cause of death is sepsis from infected skin ulcers. Prognostic factors: (1) Distribution, central (truncal) lesions ~80% mortality vs distal (limb) lesions ~50%. (2) Ulceration at presentation (worse). (3) Infection. (4) Total body surface area involved. (5) Time to diagnosis and treatment. Early aggressive multidisciplinary management (sodium thiosulfate, stop warfarin, stop Ca binders, control P and PTH) improves outcomes; case series report 30–50% healing with the full package.
Clinical Examples
📋 Case 1, Classic Truncal Calciphylaxis
Patient: 58F on HD × 6 years, AF on warfarin, BMI 34, DM. Painful violaceous abdominal/thigh lesions × 2 weeks.
Key findings: Multiple retiform plaques with central eschars on abdomen and medial thighs. Pain 10/10. Ca 9.8, P 6.4, PTH 540, Ca × P 63, INR 2.4. Bone scan: subcutaneous uptake.
Management:
Sodium thiosulfate 25 g IV after each HD
Switch warfarin → apixaban 5 mg BID
Switch calcium acetate → sevelamer 800 mg TID
Cinacalcet 30 mg daily, titrate for PTH 150–300
Vitamin K1 5 mg PO daily
Pain: hydromorphone PCA + gabapentin 100 mg at HD
Wound care, derm, palliative care all engaged
Teaching point: Truncal lesions carry the worst prognosis (~80% 1-year mortality). Treatment requires removing every calcification driver simultaneously, not just adding sodium thiosulfate.
📋 Case 2, Distal Calciphylaxis at Heparin Injection Sites
Patient: 64M on HD × 4 years, on enoxaparin for prior PE. New painful violaceous lesions at rotated SC injection sites on abdomen and thighs.
Key findings: Lesions correspond exactly to recent injection sites. P 5.8, PTH 380, Ca 9.4. No ulceration yet.
Teaching point: Lesions appearing at SC injection sites in a dialysis patient is near-pathognomonic for calciphylaxis. Microtrauma from injections triggers calcific lesions in already-vulnerable tissue. Switching to oral or IV routes (and eliminating SC heparin/insulin/enoxaparin where possible) is part of treatment.
📋 Case 3, Non-Uremic Calciphylaxis
Patient: 49F with primary biliary cholangitis (cirrhosis, MELD 18) and primary hyperparathyroidism, no CKD. Painful violaceous breast and thigh lesions.
Key findings: Ca 11.2, P 4.8, PTH 240 (high for normal renal function), albumin 2.5. Skin biopsy confirms medial arteriolar calcification.
Management:
Sodium thiosulfate 25 g IV 3×/week (no dialysis, give as outpatient infusion)
Cinacalcet for HPT, plus parathyroidectomy evaluation
Vitamin K supplementation
Aggressive nutrition (low albumin = low fetuin-A → loss of calcification inhibitor)
Wound care; pain control
Teaching point: Non-uremic calciphylaxis exists (~10% of cases). Risk factors include primary HPT, malignancy, autoimmune disease (especially with hypoalbuminemia), and cirrhosis. Same treatment principles, but no dialysis to time the STS infusion against. Also a setting where biopsy is more important since the diagnosis is less clinically obvious than in classic ESRD.
Wound exam: extension of lesions, new lesions, signs of infection (purulence, surrounding cellulitis, fever)
Phosphate, Ca, PTH: trending; binder dose adjustments; cinacalcet response
STS tolerance: bicarb (anion-gap acidosis), nausea, BP, fluid status
Anticoagulation: confirmed off warfarin; apixaban dose appropriate for renal function
Infection screen: low threshold for cultures and broad-spectrum antibiotics
Goals of care: revisit at every transition (new lesion, sepsis, refractory pain)
🎯 Summary
At a Glance
Definition
Calcific uremic arteriolopathy: medial calcification + intimal proliferation + thrombosis of dermal arterioles → painful violaceous skin necrosis in ESRD patients. The lesion is ischemic, not infective, which is why antibiotics alone do nothing and why the treatment targets calcification and thrombosis.
Epidemiology
1-4% of dialysis patients per year. F:M ~3:1. Mean age 55-60. 1-year mortality 45-80%, mostly from sepsis, through infected necrotic ulcers rather than from the vascular disease itself. That is why wound care and infection prevention carry as much weight as the specific therapy.
Top Risk Factors
ESRD on dialysis, female, obesity, diabetes, warfarin, calcium-based binders, hyperphosphatemia, hyperparathyroidism, vitamin K deficiency. Warfarin and vitamin K deficiency matter mechanistically: vitamin K activates matrix Gla protein, the main inhibitor of vascular calcification, so blocking it removes the brake.
Hallmark
Painful, often disproportionately so, violaceous retiform purpura on adipose-rich sites (abdomen, thighs, breasts). Lesions at subcutaneous injection sites are near-pathognomonic, because local trauma to fat-rich tissue triggers them, so ask about heparin and insulin injection habits.
Diagnosis
Clinical in a classic ESRD presentation. Bone scan (Tc-99m) sensitivity ~90% for non-invasive confirmation. Biopsy is the gold standard but risks a non-healing ulcer at the biopsy site, which can itself become the fatal lesion, so it is reserved for genuinely uncertain cases.
Cornerstone Therapy
Sodium thiosulfate 25 g IV after each hemodialysis session, 3 times weekly, for 3-6+ months. It chelates calcium, acts as an antioxidant and vasodilates. Expect nausea and a metabolic acidosis, and treat the duration as months rather than weeks, since early discontinuation is a common cause of apparent failure.
Stop List
Stop warfarin (switch to apixaban), stop calcium-based binders (switch to sevelamer, lanthanum or iron-based), stop fentanyl patches over lesions since absorption through necrotic skin is unpredictable, and stop aggressive surgical debridement, which extends the ischemic wound rather than healing it.
Targets
Phosphate < 5.5, Ca × P < 55, PTH 150-300, normal calcium.Intensify dialysis with a low-calcium dialysate to shift the calcium-phosphate balance out of the tissue. Vitamin K1 1-10 mg/day to restore matrix Gla protein activity.
Multidisciplinary Team
Nephrology + dermatology + wound care + palliative care + pain medicine + dietitian + surgery (if infected ulcers). Pain is severe, opioid-requiring and frequently under-treated, and palliative involvement is appropriate early given the mortality, not only at the end.
Prognostic Markers
Worse: central or truncal lesions, ulceration, infection, large surface area.Better: distal-only lesions, no ulceration, early diagnosis and the full treatment package.Ulceration is the inflection point, since it opens the route to the sepsis that kills most of these patients, so intact painful lesions are an urgent opportunity rather than a mild presentation.
Phosphate < 5.5, Ca × P < 55, low-Ca dialysate, intensified HD
Cinacalcet or etelcalcetide for HPT; parathyroidectomy if refractory
Vitamin K1 1–10 mg/day
Conservative wound care, debride only if infected; HBOT in select cases
Pain: hydromorphone or methadone IV, gabapentin (low ESRD dose), avoid morphine and fentanyl patches
Low threshold for sepsis workup and broad-spectrum antibiotics
Palliative care early
Avoid: warfarin, Ca-based binders, IV calcium for asymptomatic hypoCa, fentanyl patches over lesions, aggressive debridement of non-infected lesions, gadolinium MRI in advanced CKD.
Bacterial meningitis carries ~20% mortality even with treatment, and every hour of antibiotic delay worsens the odds (door-to-antibiotic beyond 6 hours is associated with roughly an 8-fold rise in mortality). Empiric antibiotics BEFORE LP if there will be ANY delay. Dexamethasone before or with first antibiotic dose.
🔍 Overview
CSF Patterns
Parameter
Bacterial
Viral
TB / Fungal
Opening pressure
↑↑ (> 25 cmH₂O)
Normal or mildly ↑
↑
WBC
> 1000 (PMN predominant)
10–500 (lymphocyte predominant)
10–500 (lymphocyte predominant)
Glucose
< 40 (or CSF/serum ratio < 0.4)
Normal
↓↓ (often < 20 in TB)
Protein
> 100 mg/dL (typically 100–500; the higher the value the more it favors bacterial)
50–100
↑↑ (100–500)
Gram stain
Positive in ~60–90%
Negative
AFB smear low sensitivity (~20% in TB)
Organisms by Age
Age Group
Common Organisms
Empiric Coverage
Neonates (< 1 mo)
Group B strep, E. coli, Listeria
Ampicillin + cefotaxime (or gentamicin)
Children (1 mo–18 yr)
N. meningitidis, S. pneumoniae, H. influenzae
Vancomycin + ceftriaxone
Adults (18–50)
S. pneumoniae (#1), N. meningitidis
Vancomycin + ceftriaxone
Adults > 50, immunocompromised, alcoholics
S. pneumoniae, Listeria, N. meningitidis, gram-negatives
Add ampicillin for Listeria coverage if: age > 50, immunocompromised, alcoholics, pregnancy, chronic steroids. Listeria is NOT covered by cephalosporins.
When to Get CT Before LP
CT before LP ONLY if: immunocompromised, history of CNS disease, new-onset seizure, papilledema, altered consciousness, focal neurologic deficit
If CT needed → give antibiotics BEFORE CT AND LP. Do NOT delay antibiotics for imaging.
If none of these features → LP first, no CT needed
🚨 Management
Empiric Treatment
Antibiotics within 30–60 minutes. Every hour of delay increases mortality. Do NOT wait for LP results.
Drug
Dose
Role
Vancomycin (Vancocin)
15–20 mg/kg IV q8–12h
Covers penicillin-resistant S. pneumoniae (up to 30% resistance in some regions)
Ceftriaxone (Rocephin)
2g IV q12h
Covers S. pneumoniae, N. meningitidis, H. influenzae, gram-negatives. Meningitis dose = 2g q12h (not standard 1–2g daily).
Ampicillin (Principen)
2g IV q4h
Listeria coverage. Add if age > 50, immunocompromised, alcoholism, pregnancy.
Dexamethasone (Decadron) GIVE WITH FIRST ANTIBIOTIC
0.15 mg/kg IV q6h × 4 days
European Dexamethasone Meningitis Trial, 2002: reduced mortality and hearing loss in S. pneumoniae meningitis. Give before or with first antibiotic dose. Discontinue if NOT S. pneumoniae (no benefit for other organisms). Do NOT give if already received antibiotics -benefit lost.
Acyclovir (Zovirax)
10 mg/kg IV q8h
Add if encephalitis suspected (AMS, seizures, temporal lobe findings, behavioral changes). Covers HSV encephalitis -mortality ~70% without treatment, ~20% with acyclovir.
Chemoprophylaxis -Close Contacts
N. meningitidis confirmed: close contacts (household, kissing, shared utensils, healthcare workers with unprotected airway exposure) need prophylaxis
Rifampin 600 mg PO BID × 2 days, OR ciprofloxacin 500 mg PO × 1 dose (preferred -single dose), OR ceftriaxone 250 mg IM × 1
Not needed for S. pneumoniae
Swipe for more examples
📋 Case 1, Bacterial Meningitis Empiric Therapy
Patient: 22M, worst headache of life, fever 39.4°C, nuchal rigidity, photophobia, petechial rash on trunk/extremities.
Do NOT delay antibiotics for LP or CT:
Blood cultures × 2 → antibiotics IMMEDIATELY → then CT (if indicated) → then LP.
Antibiotics within 1 hour. Every hour of delay worsens mortality.
Empiric therapy (age 18–50):
Ceftriaxone (Rocephin) 2g IV q12h (covers N. meningitidis, S. pneumoniae, H. influenzae)
+ Vancomycin (Vancocin) 15–20mg/kg IV q8–12h (covers resistant S. pneumoniae -MIC > 0.1)
+ Dexamethasone (Decadron) 0.15 mg/kg IV q6h × 4 days -give BEFORE or WITH first antibiotic dose (reduces mortality in pneumococcal meningitis -Cochrane 2015). No benefit if given after antibiotics.
If age > 50 or immunocompromised: Add ampicillin (Amoxil) 2g IV q4h for Listeria coverage.
Petechial rash → highly suspicious for N. meningitidis → droplet isolation (not airborne). Chemoprophylaxis for close contacts: ciprofloxacin (Cipro) 500mg PO × 1 dose or rifampin (Rifadin) 600mg PO BID × 2 days.
CSF expected: WBC > 1000 (PMN predominant), protein > 250, glucose < 40, Gram stain + in ~60%.
📋 Case 2, HSV Encephalitis
Patient: 34F presents with 3 days of fever, headache, bizarre behavior, and new-onset seizures.
Patient: 45M with HIV (CD4 count 65), presents with 2 weeks of progressive headache, low-grade fever, and neck stiffness. Subacute presentation suggests opportunistic infection, NOT typical bacterial meningitis.
LP: Opening pressure 32 cmH₂O (elevated), WBC 25 (lymphocytic), protein 80, glucose 30 (low). India ink: positive for encapsulated yeast. Cryptococcal antigen (CrAg): positive (titer 1:1024).
Serial LPs to manage elevated ICP (drain if OP >25, this is the #1 cause of death).
Consolidation: Fluconazole 400mg daily × 8 weeks.
Maintenance: Fluconazole 200mg daily until CD4 >200 × 6 months on ART.
Do NOT start ART immediately, wait 4-6 weeks (early ART causes IRIS → fatal cerebral edema).
Key lesson: Subacute meningitis + HIV + low CD4 = think crypto. Check CrAg. Serial LPs to manage pressure are lifesaving. Delay ART to avoid IRIS.
🔄 Updated Practice: Old teaching: dexamethasone is controversial in bacterial meningitis. Current evidence: dexamethasone (0.15 mg/kg IV q6h × 4 days) BEFORE or WITH the first antibiotic dose reduces mortality and hearing loss in PNEUMOCOCCAL meningitis (European Dexamethasone Meningitis Trial, 2002). Key: it must be given before or simultaneously with antibiotics -no benefit if given after. No proven benefit in meningococcal or gram-negative meningitis, but most centers give it empirically since you don't know the organism yet.
💊 Medications
Empiric Antibiotic Therapy -Bacterial Meningitis
Do NOT delay antibiotics. Give empiric therapy immediately after (or ideally with) blood cultures. Every hour of delay increases mortality. LP can follow antibiotics -CSF cultures remain positive for hours.
Drug
Dose
Indication
Key Notes
Ceftriaxone
2g IV q12h
Empiric coverage -S. pneumoniae, N. meningitidis, H. influenzae, GNRs
Higher dose than standard (meningeal dosing) -needed for adequate CSF penetration across BBB.
Vancomycin
15-20 mg/kg IV q8-12h
Empiric -covers penicillin-resistant S. pneumoniae (up to 30% resistance in some areas)
Target AUC/MIC 400-600 (AUC-guided dosing per 2020 ASHP/IDSA guidelines). Load with 25-30 mg/kg if severe.
Dexamethasone
0.15 mg/kg IV q6h × 4 days
Give BEFORE or WITH first antibiotic dose -reduces inflammation from bacterial lysis
Proven mortality benefit in pneumococcal meningitis de Gans, 2002. Discontinue if non-pneumococcal etiology confirmed. Must give before/with antibiotics -no benefit if given after.
Ampicillin
2g IV q4h
Add if age > 50, immunocompromised, pregnant, or alcoholic -covers Listeria monocytogenes
Listeria is intrinsically resistant to cephalosporins. Must add ampicillin for Listeria coverage in at-risk patients.
Adjust for renal function. Duration 14-21 days for HSV encephalitis. Maintain adequate hydration to prevent crystalluria.
Standard empiric regimen: Ceftriaxone + vancomycin + dexamethasone for all adults. ADD ampicillin if age > 50 or immunocompromised. ADD acyclovir if HSV suspected. Narrow based on culture and susceptibility results.
📋 On Rounds
Why give dexamethasone before antibiotics in bacterial meningitis?
When antibiotics lyse bacteria, cell wall fragments (lipoteichoic acid, peptidoglycan) are released → massive inflammatory cascade in the subarachnoid space → cerebral edema, increased ICP, neuronal damage. Dexamethasone dampens this inflammatory burst.European Dexamethasone Meningitis Trial, 2002: dex given before/with the first antibiotic dose in S. pneumoniae meningitis reduced mortality from 15% to 7% and hearing loss significantly.
Why is the ceftriaxone dose 2g q12h for meningitis instead of the usual 1–2g daily?
The blood-brain barrier limits antibiotic penetration into the CSF. Even with meningeal inflammation (which increases permeability), only a fraction of serum drug levels reach the CSF. To achieve adequate bactericidal concentrations in the CSF, you need higher and more frequent dosing than for systemic infections. Ceftriaxone 2g q12h achieves CSF levels that reliably exceed the MIC for S. pneumoniae and N. meningitidis.
When do you need a CT head before LP, and what happens if it delays treatment?
CT before LP is needed if: immunocompromised, history of CNS disease, new-onset seizure, papilledema, altered consciousness, focal neurologic deficit. These identify patients at risk for brain herniation from LP. If CT is needed: draw blood cultures → start empiric antibiotics + dexamethasone IMMEDIATELY → then CT → then LP when safe. Do NOT delay antibiotics for CT or LP.
How do you interpret CSF results to differentiate bacterial from viral meningitis?
Bacterial: WBC > 1,000 (PMN predominant > 80%), protein > 100 (often 100-500), glucose < 40 (or CSF/serum glucose ratio < 0.4), gram stain positive in ~60-90%. Viral: WBC 10-500 (lymphocyte predominant), protein 50-100, glucose normal, gram stain negative. TB/fungal: WBC 10-500 (lymphocyte predominant), protein very high (> 200), glucose LOW (like bacterial). Pearl: early bacterial meningitis can have lymphocyte predominance (first 12-24h)
Clinical Examples
📋 Case 1, Community-Acquired Bacterial Meningitis
Patient: 42M, previously healthy, presents with 18 hours of severe headache, fever, neck stiffness, and photophobia. Found confused by coworkers.
Key findings: Temp 39.6°C, HR 112, BP 88/52, GCS 12. Nuchal rigidity, positive Kernig and Brudzinski signs, petechial rash on trunk. CSF: WBC 2,400 (95% PMN), protein 320, glucose 18 (serum 110), gram stain: gram-negative diplococci. Lactate 8.4.
Management:
Dexamethasone 0.15 mg/kg IV q6h x 4 days -- give BEFORE or WITH first antibiotic dose de Gans, 2002
Empiric: ceftriaxone 2g IV q12h + vancomycin 15-20 mg/kg IV q8-12h (covers resistant pneumococcus)
Gram-negative diplococci = Neisseria meningitidis. Narrow to penicillin G or ceftriaxone once confirmed
Droplet precautions x 24h of effective antibiotics. Chemoprophylaxis for close contacts (rifampin, ciprofloxacin, or ceftriaxone IM)
Teaching point: Dexamethasone must be given BEFORE or WITH antibiotics to be effective. If antibiotics have already been given, dexamethasone has no benefit. Do not delay antibiotics for LP.
📋 Case 2, Meningitis in an Immunocompromised Patient
Patient: 67F on chronic prednisone 15 mg daily for polymyalgia rheumatica, presents with 3 days of low-grade fever, progressive headache, and subtle personality changes. No classic meningismus.
Key findings: Temp 38.3°C, HR 88, BP 134/72. Oriented but slow to respond. Mild neck stiffness only. CSF: WBC 680 (78% PMN), protein 245, glucose 22 (serum 105), gram stain: gram-positive rods.
Management:
Gram-positive rods in immunocompromised = Listeria monocytogenes until proven otherwise
Empiric: ceftriaxone 2g IV q12h + vancomycin + ampicillin 2g IV q4h (cephalosporins do NOT cover Listeria)
Dexamethasone: controversial in Listeria; give empirically and discontinue once Listeria confirmed
Ampicillin x 21 days minimum for Listeria meningitis (longer than other organisms due to intracellular persistence)
Teaching point: Add ampicillin for Listeria coverage in age >50, immunocompromised, pregnant, or alcoholic patients. Cephalosporins do NOT cover Listeria. Listeria can present subacutely without classic meningeal signs.
📋 Case 3, Post-Neurosurgical Meningitis
Patient: 56M, post-op day 8 from craniotomy for meningioma resection, develops new fever, worsening headache, and declining mental status. External ventricular drain (EVD) in place.
Key findings: Temp 39.2°C, HR 108, GCS declining from 15 to 12 over 24h. CSF from EVD: WBC 1,800 (90% PMN), protein 380, glucose 12 (serum 98), gram stain: gram-positive cocci in clusters.
Management:
Gram-positive cocci in clusters post-neurosurgery = Staphylococcus. Empiric: vancomycin IV + cefepime 2g IV q8h (covers MRSA + Pseudomonas)
Consider intrathecal/intraventricular vancomycin (5-20 mg daily) if poor response to IV therapy alone
EVD removal or exchange if feasible -- source control is critical for device-related ventriculitis
Do NOT give dexamethasone in post-surgical meningitis (no evidence of benefit)
Teaching point: Post-neurosurgical meningitis has completely different microbiology (Staph, gram-negatives) than community-acquired. Vancomycin + anti-pseudomonal beta-lactam is the empiric regimen. Device removal is essential for cure.
⚡ Summary
Summary
Antibiotics Within 30 to 60 Minutes
Every hour of delay worsens the odds, and door-to-antibiotic beyond 6 hours is associated with roughly an 8-fold rise in mortality.Give empiric antibiotics BEFORE the LP if there will be any delay: blood cultures and CSF chemistry, cell count and PCR remain informative after a dose of antibiotic. Mortality is about 20% even with treatment.
Dexamethasone Before or With the First Dose
0.15 mg/kg IV q6h for 4 days, given before or with the first antibiotic.It reduces mortality and hearing loss, above all in pneumococcal meningitis, by blunting the inflammatory surge released when bacteria lyse. Given after the antibiotic it does not work, so this is a sequencing rule, not an optional adjunct.
Add Ampicillin for Listeria in the Right Patients
Age over 50, immunocompromised, alcohol use disorder, pregnancy, or chronic steroids.Listeria is not covered by cephalosporins, which is the single most consequential empiric gap. Standard empiric therapy otherwise is vancomycin plus ceftriaxone, with vancomycin for resistant pneumococcus.
CT Before LP Only for Specific Indications
Immunocompromise, a history of CNS disease, new seizure, papilledema, altered consciousness or a focal neurologic deficit.Everyone else can be tapped without a scan, and scanning unnecessarily is the commonest cause of antibiotic delay. If CT is needed, give the antibiotics first.
Read the CSF Pattern
Bacterial: high opening pressure, thousands of neutrophils, high protein, low glucose (CSF-to-serum ratio below 0.4).Viral: lymphocytic, normal glucose, modest protein.Tuberculous and fungal: lymphocytic with very low glucose and very high protein.Early bacterial meningitis can be neutrophil-poor, so a modest count with a very low glucose still means bacterial until proven otherwise.
Cover HSV When the Picture Is Encephalitic
Altered mental status, seizures, personality change or focal deficits mean add acyclovir while awaiting the CSF PCR. HSV encephalitis untreated has 70% mortality and delay is what drives it, so the cost of empiric acyclovir is trivial by comparison. Temporal lobe involvement on MRI is the classic finding.
Isolate and Prophylax the Contacts
Droplet precautions for suspected meningococcal disease until 24 h of effective therapy.Chemoprophylaxis for close contacts of Neisseria meningitidis (household, childcare, direct exposure to secretions, and healthcare workers who performed unprotected airway management) with ciprofloxacin, rifampin or ceftriaxone. Also for H. influenzae type b contacts in defined households.
Follow the Complications
Seizures, cerebral edema and raised intracranial pressure, hydrocephalus, SIADH, subdural empyema and venous sinus thrombosis.Hearing loss is the commonest long-term sequela, so arrange audiology before discharge, particularly in children and after pneumococcal disease. Look for a source: sinusitis, otitis, endocarditis, or a CSF leak in recurrent disease.
RoundsRx Infographic Series · #22 · Sepsis & Infection · PDF 171 KB
Text version
Bacterial Meningitis -Text Version of the One Pager
Antibiotics within the hour. Never hold them for a CT or an LP. Blood cultures, then dexamethasone, then antibiotics, then imaging if indicated, then the LP. CSF cultures stay positive for hours after the first dose.
Recognize it
Fever, headache, neck stiffness and altered mental status, but the classic triad is complete in fewer than half, so its absence does not exclude meningitis. Also photophobia, seizures, focal deficit, and a purpuric rash (think meningococcus and move faster).
CT before LP only if
Immunocompromised, known CNS disease, new-onset seizure, papilledema, reduced consciousness, or focal neurological deficit. With none of these, go straight to LP. The scan excludes a mass lesion before you release CSF pressure; it does not diagnose meningitis. If a CT is needed, the antibiotics go in first.
CSF interpretation
Bacterial: opening pressure markedly raised (often > 25 cmH₂O), WBC 1,000-5,000 neutrophil-predominant, CSF:serum glucose ratio < 0.4, protein > 100 mg/dL (typically 100-500), Gram stain positive in 60-90%.
Viral: normal or mildly raised pressure, WBC 10-500 lymphocytic, normal glucose, protein 50-100, HSV and enterovirus PCR.
TB or fungal: raised pressure, WBC 10-500 lymphocytic, low glucose (often profoundly), protein often > 200, AFB smear (low yield), GeneXpert, culture.
Caveat: early bacterial meningitis can be lymphocyte-predominant in the first 12-24 hours, and prior antibiotics blunt every one of these numbers.
Empiric therapy (adult, community-acquired)
Ceftriaxone 2 g IV q12h. The meningeal dose is 2 g twice daily, not the usual once-daily gram, because the blood-brain barrier admits only a fraction of the serum level.
Vancomycin 25-30 mg/kg load, then 15-20 mg/kg q8-12h, targeting AUC/MIC 400-600. Added for resistant pneumococcus. Dose by AUC, not by trough: the 2020 ASHP/IDSA/PIDS/SIDP revision moved off trough-only monitoring, because a trough of 15-20 (the superseded 2009 surrogate) drives nephrotoxicity without reliably confirming the AUC.
Ampicillin 2 g IV q4h for Listeria if age over 50, pregnant, immunosuppressed, on chronic steroids, or alcohol-dependent. Cephalosporins do not cover Listeria.
Aciclovir 10 mg/kg IV q8h if HSV encephalitis is plausible. Untreated it kills around 70%; treated, closer to 20%.
Dexamethasone 0.15 mg/kg IV q6h for 4 days, given before or with the first antibiotic dose. Antibiotics lyse bacteria and release cell-wall fragments, and that inflammatory burst causes the edema and hearing loss, so steroid given afterwards has missed the event. Continue only if pneumococcal.
Pathogen-directed therapy and duration
N. meningitidis: ceftriaxone, 7 days. Notify public health; droplet isolation for the first 24 hours of effective therapy.
S. pneumoniae: ceftriaxone, keep vancomycin if resistant, 10-14 days. The only organism in which dexamethasone is continued.
H. influenzae: ceftriaxone, 7-10 days. Notifiable; prophylaxis for contacts.
L. monocytogenes: ampicillin plus gentamicin for synergy, at least 21 days. It survives intracellularly, so short courses relapse.
Gram-negative or post-neurosurgical: meropenem with or without an aminoglycoside, about 21 days. Remove or exchange any EVD.
Contact prophylaxis for meningococcus: ciprofloxacin 500 mg orally once, rifampin 600 mg twice daily for 2 days, or ceftriaxone 250 mg IM once. None is needed for pneumococcus.
When it isn't going well
Not improving at 48 h: repeat the LP. Think resistant pneumococcus, an undrained focus (subdural empyema, brain abscess, mastoiditis, sinusitis), or the wrong diagnosis. Re-image before broadening antibiotics.
Early complications: raised intracranial pressure, seizures, SIADH with hyponatremia. Late: brain abscess, hydrocephalus, cerebral venous sinus thrombosis, and sensorineural hearing loss. Arrange audiometry before discharge.
Neuroprotection: head up 30°, treat seizures (benzodiazepine then levetiracetam), analgesia, maintain normocapnia, avoid hypotonic fluids. Neurosurgery for hydrocephalus needing CSF diversion.
The most common bacterial infection in adults. The biggest mistake residents make: treating asymptomatic bacteriuria. A positive UA or culture in a patient without urinary symptoms is NOT a UTI -it's colonization. Don't treat the lab.
🔍 Overview
Classification
Type
Definition
Treatment Duration
Uncomplicated cystitis
Lower UTI (dysuria, frequency, urgency) in non-pregnant, premenopausal women with normal urinary tract
3–5 days
Complicated UTI
UTI with: male sex, pregnancy, structural abnormality, catheter, immunosuppression, renal transplant, recent instrumentation
5–7 days (outpatient FQ) or 10–14 days (if complicated/inpatient)
Catheter-associated UTI (CAUTI)
Catheter in place (or removed within 48h) + symptoms + culture ≥ 10³ CFU/mL. NOT the same as asymptomatic bacteriuria from catheter.
7 days (remove/replace catheter first)
Asymptomatic Bacteriuria -Do NOT Treat
Positive UA/culture WITHOUT urinary symptoms = asymptomatic bacteriuria. Do NOT treat. Treating ASB drives antibiotic resistance, C. diff risk, and adverse drug effects without benefit. IDSA, 2019
Exceptions (treat ASB): pregnancy (risk of pyelonephritis → preterm labor), pre-urologic procedure with mucosal bleeding expected
Do NOT treat ASB in: elderly, catheterized patients, diabetics, spinal cord injury, nursing home residents -even if pyuria is present
Pyuria alone is NOT an indication for treatment -it reflects inflammation, not necessarily infection
💊 Management
Empiric Antibiotics
Diagnosis
First-Line
Alternative
Notes
Uncomplicated cystitis
Nitrofurantoin 100 mg BID × 5 days 1ST LINE
TMP-SMX DS BID × 3 days (if local resistance < 20%). Fosfomycin 3g PO × 1 dose.
Avoid fluoroquinolones for uncomplicated cystitis -FDA warning, collateral damage, save for complicated infections. Nitrofurantoin: avoid if CrCl < 30 (ineffective + toxic). IDSA/ESCMID UTI Guidelines, 2011
Pyelonephritis -outpatient
Ciprofloxacin (Cipro) 500 mg BID × 7 days or levofloxacin (Levaquin) 750 mg daily × 5 daysPeterson et al., 2008
TMP-SMX DS BID × 14 days (if susceptible). Ceftriaxone 1g IM × 1 + oral step-down.
FQs are appropriate here (upper tract). Get urine culture to guide de-escalation. Consider admission if: unable to tolerate PO, sepsis, pregnancy, concern for obstruction.
Pyelonephritis -inpatient
Ceftriaxone (Rocephin) 1g IV daily 1ST LINE
Ciprofloxacin 400 mg IV q12h. Piperacillin-tazobactam if MDR risk. Meropenem if ESBL.
Step down to oral once afebrile × 48h and tolerating PO. Total duration depends on oral step-down agent: FQ 5–7 days, TMP-SMX 7–10 days, beta-lactam 10–14 days. CT abdomen if no improvement in 48–72h (abscess? obstruction?).
CAUTI
Based on local antibiogram + culture
Broader coverage initially (ceftriaxone or FQ). Narrow based on susceptibilities.
Remove or replace the catheter first -this alone can resolve the infection. Culture from NEW catheter. Duration 7 days. IDSA CAUTI, 2010 Assess if catheter is still needed -remove ASAP.
ESBL UTI: For uncomplicated ESBL cystitis, nitrofurantoin and fosfomycin retain activity. For ESBL pyelonephritis or complicated UTI, carbapenems (ertapenem, meropenem) are required. Avoid fluoroquinolones even if susceptible in vitro - clinical failure rates are higher with ESBL producers. Doi et al., 2015
Recurrent UTI (>= 3 episodes/year): Evaluate for structural abnormalities (renal ultrasound, post-void residual). Non-antibiotic prevention: vaginal estrogen (postmenopausal, restores lactobacilli and lowers vaginal pH), cranberry products, D-mannose. Antibiotic prophylaxis options: post-coital TMP-SMX, continuous low-dose nitrofurantoin. Set expectations on cranberry: the evidence is mixed. The best-known single RCT was negativeBarbosa-Cesnik, 2011, while the pooled Cochrane review does find a modest benefit in women with recurrent UTI Cochrane, 2023. Offer it as a low-harm adjunct, not as established therapy.
Pregnancy UTI: Screen ALL pregnant women for ASB at 12-16 weeks (one of only two situations where ASB requires treatment). Treat with cephalexin, amoxicillin, or nitrofurantoin (avoid in first trimester and at term). Untreated ASB in pregnancy progresses to pyelonephritis in 20-30% of cases. Smaill & Vazquez (Cochrane), 2019
🔄 Updated Practice: Complicated UTI was traditionally defined by a checklist of host factors (male, catheter, pregnant, etc.). The modern definition is simpler: any UTI that extends beyond the bladder. Additionally, asymptomatic bacteriuria should NOT be treated (except in pregnancy and before urologic procedures) -old practice was to treat all positive urine cultures.
📋 On Rounds
An 85-year-old with dementia has a positive UA (leukocyte esterase, bacteria) but no urinary symptoms. Should you treat?
No. This is asymptomatic bacteriuria (ASB). Up to 50% of elderly nursing home residents and 100% of chronically catheterized patients have bacteriuria without true infection. Treating ASB does not reduce mortality, morbidity, or subsequent symptomatic UTIs -but it does increase antibiotic resistance and C. diff risk. The exception: confusion in the elderly is NOT a urinary symptom. AMS + bacteriuria does not automatically = UTI.
Why should fluoroquinolones be avoided for uncomplicated cystitis?
FQ's (ciprofloxacin, levofloxacin) carry FDA black box warnings for tendon rupture, peripheral neuropathy, aortic dissection, and CNS effects -risks that are disproportionate for a self-limiting infection like uncomplicated cystitis. Nitrofurantoin or TMP-SMX are equally effective with far less toxicity. FQ's should be reserved for complicated UTIs, pyelonephritis when oral is needed, or resistant organisms.
An elderly patient has a positive urine culture but no urinary symptoms. Should you treat?
NO -this is asymptomatic bacteriuria (ASB), and treating it causes harm. ASB is defined as bacteria in urine without urinary symptoms (dysuria, frequency, urgency, suprapubic pain, fever). Do NOT treat ASB -antibiotics don't improve outcomes and promote resistance + C. diff. This is one of the most common antibiotic stewardship violations. Only 2 exceptions where you DO treat ASB: (1) Pregnancy, untreated ASB progresses to pyelonephritis in 20-30% and is linked to preterm delivery and low birth weight; screen and treat all pregnant women. (2) Before urologic procedures with mucosal trauma (TURP, ureteroscopy with stone manipulation), prevents post-procedure bacteremia and sepsis. Pre-procedure antibiotics only, not chronic treatment.
What antibiotics require dose adjustment in renal failure for UTI, and which don't?
Nitrofurantoin: AVOID if CrCl < 30 (doesn't concentrate in urine → ineffective, and accumulates → peripheral neuropathy). TMP-SMX: avoid if CrCl < 15. Watch for hyperkalemia (trimethoprim blocks ENaC). Ciprofloxacin: reduce to 250 mg BID if CrCl < 30. Ceftriaxone: no adjustment needed (biliary excretion). Fosfomycin: single 3g dose, no adjustment needed, but less effective in complicated UTI.
A patient with uncomplicated cystitis has an E. coli culture showing resistance to TMP-SMX but susceptibility to ciprofloxacin. What is the best treatment?
Still nitrofurantoin 100 mg BID x 5 days. Even with TMP-SMX resistance, the answer for uncomplicated cystitis is NOT fluoroquinolones. Nitrofurantoin remains first-line regardless of TMP-SMX susceptibility. FQs carry FDA black box warnings for tendon rupture, neuropathy, and aortic dissection - risks far exceeding the benefit for a self-limited infection. FQs should be reserved for pyelonephritis or complicated UTI.
How do you distinguish UTI from asymptomatic bacteriuria in a catheterized patient?
Catheterized patients almost universally develop bacteriuria by 5-7 days. CAUTI requires new systemic symptoms (fever > 38C, rigors, altered mental status, hemodynamic instability) plus culture >= 10^3 CFU/mL from a freshly placed catheter. Pyuria alone is NOT diagnostic. The IDSA 2010 CAUTI guidelines emphasize that neither pyuria nor bacteriuria alone warrants treatment. IDSA CAUTI Guidelines, 2010
What is the role of urine culture in uncomplicated cystitis?
No urine culture needed for uncomplicated cystitis - treat empirically. Culture is indicated for: complicated UTI, pyelonephritis, recurrent UTI (>= 3/year), treatment failure, suspected resistant organisms, and male UTI. For uncomplicated cystitis, the AUA/CUA/SUFU 2019 guidelines recommend empiric treatment based on local antibiogram. Culturing every UTI drives unnecessary antibiotic changes and delays treatment.
A patient treated for pyelonephritis remains febrile after 72 hours of appropriate antibiotics. What is the next step?
CT abdomen/pelvis with IV contrast to rule out perinephric abscess, renal abscess, or obstruction (obstructive pyelonephritis/pyonephrosis). Perinephric abscess occurs in ~5% of pyelonephritis cases and requires drainage. Obstructive pyonephrosis is a urologic emergency requiring percutaneous nephrostomy or ureteral stent. Also reassess culture susceptibilities and consider resistant organism or alternative diagnosis.
What is the evidence for short-course antibiotic therapy in UTI?
In adults, short courses hold up. Cystitis: nitrofurantoin 5 days, TMP-SMX 3 days (IDSA/ESCMID 2011). Pyelonephritis in women: ciprofloxacin 7 days is non-inferior to 14Sandberg, 2012, and levofloxacin 750 mg × 5 days is non-inferior to ciprofloxacin × 10 days Peterson, 2008. Shorter courses cut C. diff risk, resistance, and adverse effects without losing cure rates. Do not extrapolate to children: the SCOUT trial SCOUT, 2023 found 5 days was not non-inferior to 10 in children aged 2 months to 10 years (4.1% vs 0.6% persistent UTI).
Case 1: Complicated Pyelonephritis
Presentation: 45F presents with 2 days of fever (39.2°C), right flank pain, nausea, and dysuria. Labs: WBC 16.2, Cr 1.1. UA: pyuria, positive nitrites, many bacteria. Blood cultures drawn × 2.
Initial Management: Started on ceftriaxone 1g IV daily empirically. IV fluids for hydration. Urine and blood cultures pending.
Hospital Course: Blood cultures return positive for E. coli (pan-sensitive). Urine culture confirms same organism. Sensitivities show susceptibility to TMP-SMX (Bactrim). De-escalated to TMP-SMX DS 1 tab PO BID. Afebrile by 48h. Total antibiotic course: 10-14 days (extended due to bacteremia).
Key Teaching Points: Always obtain blood cultures in pyelonephritis (positive in ~25%). Bacteremia extends duration to 10-14 days. If no clinical improvement by 48-72h → CT abdomen/pelvis to rule out perinephric abscess or obstruction. De-escalate based on sensitivities, not empirically.
Case 2: Catheter-Associated UTI (CAUTI)
Presentation: 70M, post-op day 5 from hip replacement, Foley catheter in place × 5 days. New fever (38.6°C), no other localizing symptoms. UA: positive LE, positive nitrites, WBC > 100. Urine culture: Klebsiella pneumoniae > 100K CFU/mL.
Critical Decision: Is this CAUTI or asymptomatic bacteriuria? With a catheter in place, bacteriuria is nearly universal by day 5. Pyuria alone does NOT indicate infection in catheterized patients. However, this patient has new fever without another source → treat as CAUTI.
Management: Foley removed immediately (or replaced if still needed). Started ceftriaxone 1g IV daily. Narrowed to cephalexin (Keflex) 500 mg PO QID based on sensitivities. Total duration: 7 days (shorter course for CAUTI with prompt catheter removal).
Key Teaching Points: Step 1 is always remove or replace the catheter. Do NOT treat asymptomatic bacteriuria in catheterized patients, it does not reduce complications and promotes resistance + C. difficile. Fever is the most reliable sign of true CAUTI. Duration is 7 days (not 10-14) when catheter is removed promptly.
Case 3: ESBL-Producing E. coli UTI
Presentation: 32F with history of 4 UTIs in the past year, now presenting with dysuria and frequency × 2 days. No fever, no flank pain. Prior cultures have shown progressively resistant E. coli. Current urine culture: ESBL-producing E. coli, resistant to TMP-SMX, ciprofloxacin, ampicillin, and ceftriaxone. Susceptible to nitrofurantoin, fosfomycin, and carbapenems.
Management (Uncomplicated Cystitis): Since this is uncomplicated lower tract infection, started nitrofurantoin (Macrobid) 100 mg PO BID × 5 days. Nitrofurantoin retains activity against many ESBL organisms for cystitis because it concentrates in urine. Fosfomycin (Monurol) 3g PO × 1 is an alternative.
If This Were Complicated/Pyelonephritis: Would require ertapenem (Invanz) 1g IV daily or meropenem 1g IV q8h. Carbapenems are the backbone for ESBL complicated infections. Avoid fluoroquinolones even if susceptible in vitro, clinical failure rates are higher with ESBL producers.
Key Teaching Points: ESBL cystitis can often be treated with oral agents (nitrofurantoin, fosfomycin). Save carbapenems for complicated or upper tract ESBL infections. Fluoroquinolones should be avoided for ESBL. Consult ID for recurrent ESBL infections, consider suppressive prophylaxis and evaluation for structural abnormalities.
📣 Sample Presentation
One-Liner
"Ms. Chen is a 28-year-old healthy woman presenting with 3 days of dysuria, frequency, and urgency. No fever, no flank pain. UA: positive LE, positive nitrites, WBC 80. Consistent with uncomplicated cystitis."
Key Points to Cover on Rounds
Uncomplicated cystitis in a healthy, non-pregnant female. Treatment: nitrofurantoin 100 mg BID × 5 days (first-line). Avoided fluoroquinolones (FDA black box, disproportionate risk for self-limiting infection). Urine culture sent but treatment is empiric -will adjust only if resistant. No imaging needed. Plan: symptom relief with phenazopyridine 200 mg TID × 2 days, return if fever/flank pain develop (would indicate pyelonephritis).
Monitoring Parameters -Urinary Tract Infections
Parameter
Frequency
Target / Action
Symptom resolution
48-72h after starting antibiotics
Dysuria, frequency, urgency should improve within 48-72h. If not improving → recheck culture, consider resistant organism, imaging for complication (abscess, obstruction).
Temperature (pyelonephritis)
q4-8h inpatient
Fever should defervesce within 48-72h on appropriate antibiotics. Persistent fever → CT abdomen/pelvis to rule out perinephric abscess or obstruction.
Urine culture results
Check at 48h when available
Narrow antibiotic based on susceptibilities. De-escalate from IV to PO when afebrile 24-48h and tolerating PO.
Creatinine
At baseline; repeat if on nephrotoxic agents or pyelonephritis
Monitor for AKI in pyelonephritis. Adjust antibiotic dosing for renal function (nitrofurantoin ineffective if CrCl < 30).
Blood cultures (pyelonephritis)
At presentation; no routine repeat
Positive in ~20-30% of pyelonephritis. Guides duration (bacteremia may warrant 10-14 day course). Repeat only if persistent bacteremia suspected.
Do NOT repeat UA or urine culture for "test of cure." Bacteriuria can persist after successful treatment and does not require retreatment if the patient is asymptomatic. Repeating cultures leads to unnecessary antibiotic courses and C. diff risk.
🧪 Workup
Diagnostic Workup - UTI & Pyelonephritis
Workup depends on UTI classification. Uncomplicated cystitis: UA dipstick sufficient, no culture needed. Complicated UTI/pyelonephritis: UA + urine culture + blood cultures.
Test
When to Order
Interpretation
UA dipstick
All suspected UTIs
Leukocyte esterase (sensitivity ~75-96%) and nitrites (specificity ~90% but only detects Enterobacteriaceae). Negative nitrites does NOT rule out UTI.
Urine microscopy
Equivocal UA or complicated UTI
WBC > 10/hpf supports UTI. WBC casts suggest pyelonephritis. Bacteria on gram stain corresponds to >= 10^5 CFU/mL.
Urine culture
Complicated UTI, pyelonephritis, recurrent UTI, treatment failure, male UTI
>= 10^5 CFU/mL = significant. >= 10^3 CFU/mL with symptoms can be significant (especially CAUTI). Mixed flora suggests contamination - repeat clean catch.
Blood cultures
Pyelonephritis, sepsis, complicated UTI
Positive in ~20-30% of pyelonephritis. Same organism as urine confirms source. May extend treatment duration to 10-14 days.
CT abdomen/pelvis
No improvement at 48-72h, suspected obstruction or abscess
Rule out perinephric abscess, pyonephrosis, obstructing stone. Contrast required for abscess detection. Stunell et al., 2007
Hydronephrosis suggests obstruction. Post-void residual > 200 mL suggests retention. Safe in pregnancy.
💊 Medications
Antibiotic Therapy -Urinary Tract Infections
Uncomplicated cystitis does NOT require urine culture. Treat empirically. Reserve cultures for complicated UTI, pyelonephritis, recurrent infections, or treatment failure. Always check local antibiogram for resistance patterns.
Indication
Drug
Dose
Duration
Key Notes
Uncomplicated Cystitis
Nitrofurantoin (Macrobid)FIRST-LINE
100 mg PO BID
5 days
Avoid if CrCl < 30 (poor urinary concentration). Take with food. Not effective for pyelonephritis (no tissue penetration).
TMP-SMX DS (Bactrim)
1 DS tab PO BID
3 days
Use only if local E. coli resistance < 20%. Check sulfa allergy. Avoid in 3rd trimester pregnancy.
Fosfomycin (Monurol)
3g PO × 1 dose
Single dose
Convenient but less effective than multi-day regimens. Good option for MDR organisms (ESBL). Not for complicated UTI.
Pyelonephritis (inpatient)
CeftriaxoneFIRST-LINE
1g IV daily
Step down to PO when afebrile 24-48h; total duration by PO agent: FQ 5-7d, TMP-SMX 7-10d, beta-lactam 10-14d
Broad GNR coverage. Obtain blood and urine cultures before starting. Transition to PO based on susceptibilities.
Ciprofloxacin
400 mg IV q12h
Step down to PO 500 mg BID; total 5-7 days
Fluoroquinolone -FDA black box warning (tendon, nerve, CNS effects). Use only if no safer alternative. Shorter course (5-7d) if FQ used Sandberg, 2012.
Piperacillin-tazobactam
3.375g IV q8h (extended infusion)
Narrow when cultures available
Reserve for severely ill or concern for resistant organisms. De-escalate promptly.
Pyelonephritis (outpatient)
Ciprofloxacin
500 mg PO BID
5-7 days
Most effective oral option for pyelo. Check local resistance. Give initial dose of ceftriaxone 1g IV/IM if any concern.
TMP-SMX DS
1 DS tab PO BID
7-14 days
Only if susceptibility confirmed. Give initial parenteral dose (ceftriaxone 1g) for reliable early bactericidal activity.
Asymptomatic bacteriuria: Do NOT treat except in pregnancy or pre-urologic procedure. Positive UA/culture without dysuria, frequency, or urgency = colonization, not infection. Treating ASB drives resistance and causes C. diff.
⚡ Summary
Summary
Do Not Treat Asymptomatic Bacteriuria
A positive urinalysis or culture without urinary symptoms is colonization.Treating it drives resistance and C. difficile without benefit (IDSA 2019). The only two exceptions are pregnancy and before a urologic procedure with anticipated mucosal bleeding.Pyuria alone is not an indication to treat, and a foul-smelling or cloudy specimen is not a diagnosis.
Do Not Send Urine Reflexively in a Confused Elderly Patient
Bacteriuria is present in a large proportion of older adults and in essentially everyone with a chronic catheter, so a positive culture in a delirious patient is frequently incidental. Look for the real cause of the delirium: attributing it to a UTI is one of the commonest diagnostic anchors in geriatrics.
Classify Before Prescribing
Uncomplicated cystitis: a non-pregnant woman with a normal urinary tract.Complicated: male sex, pregnancy, catheter, obstruction, stones, immunosuppression or a structural or functional abnormality.Pyelonephritis: fever, flank pain, costovertebral angle tenderness, systemic illness. The category sets both the drug and the duration.
First-Line for Uncomplicated Cystitis
Nitrofurantoin for 5 days, TMP-SMX for 3 days where local resistance is under 20%, or single-dose fosfomycin.Avoid fluoroquinolones for simple cystitis: tendon rupture, aortic aneurysm, neuropathy and C. difficile risk make them a poor trade when narrower agents work. Nitrofurantoin does not treat pyelonephritis, because it does not achieve tissue levels.
Pyelonephritis Needs Different Drugs and Longer Courses
Ceftriaxone or another agent with good renal tissue penetration, 7 to 14 days depending on the agent and response.Get blood and urine cultures and admit for vomiting, hemodynamic instability, pregnancy or failure of outpatient therapy. Image if there is no improvement in 48 to 72 h, looking for obstruction or abscess, since an obstructed infected kidney needs urgent decompression, not more antibiotics.
Know What ESBL Changes
For uncomplicated ESBL cystitis, nitrofurantoin and fosfomycin retain activity.ESBL pyelonephritis or complicated infection requires a carbapenem, ertapenem or meropenem. Avoid fluoroquinolones even when they test susceptible, because failure rates are high.
Pregnancy Is the Exception to Almost Every Rule
Screen all pregnant women for asymptomatic bacteriuria at 12 to 16 weeks and treat it, because untreated it progresses to pyelonephritis and preterm labor. Use cephalexin, amoxicillin or nitrofurantoin, avoiding nitrofurantoin in the first trimester and at term, and avoid TMP-SMX in the first trimester and near delivery.
Work Up Recurrence Rather Than Re-Treating It
Three or more episodes a year warrants a renal ultrasound and a post-void residual.Non-antibiotic prevention first: vaginal estrogen in postmenopausal women, which restores lactobacilli and lowers vaginal pH, plus hydration and voiding habits. Remove or exchange a chronic catheter before treating a catheter-associated infection, since the biofilm makes antibiotics alone ineffective.
RoundsRx Infographic Series · #25 · Sepsis & Infection · PDF 143 KB
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UTI -Cystitis & Pyelonephritis
Cystitis: nitrofurantoin × 5d (avoid FQ). Pyelo: ceftriaxone or cipro. ASB: treat ONLY in pregnancy or pre-urologic surgery. Don't treat pyuria in catheterized patients.
🧪 Uncomplicated Cystitis
Dysuria + frequency + urgency in healthy non-pregnant female. Nitrofurantoin 100 BID × 5d (first-line). TMP-SMX × 3d if susceptible. Avoid fluoroquinolones.
🚨 Pyelonephritis
Fever + flank pain + CVA tenderness. Ceftriaxone 1g IV (inpatient) or cipro 500 BID × 7d (outpatient, if susceptible). Blood cultures + urine culture. Imaging if not improving at 48-72h.
⚠️ Asymptomatic Bacteriuria
Do NOT treat ASB -causes harm (resistance + C. diff). Only 2 exceptions: (1) Pregnancy. (2) Pre-urologic procedures with mucosal bleeding. Not in elderly, catheterized, diabetic, or nursing home.
💊 Key Drugs
Nitrofurantoin100 mg BID × 5d
TMP-SMX DS1 tab BID × 3d
Ceftriaxone1g IV daily
Ciprofloxacin500 mg BID × 7d (pyelo)
⚠️ Pitfalls
FQ for uncomplicated cystitis (disproportionate risk)
What the IM resident needs to know: opportunistic infections by CD4 count, when to start ART, immune reconstitution inflammatory syndrome (IRIS), and drug interactions. ART is now "treat all, treat early" -start regardless of CD4.
Azithromycin 1200 mg weekly (if ART not started yet)
Clarithromycin + ethambutol ± rifabutin
CD4 < 200 = AIDS-defining. PCP and toxo prophylaxis start here. TMP-SMX DS daily covers both. Discontinue prophylaxis when CD4 > 200 for ≥ 3 months on ART.
💊 ART Basics
When to Start ART
Start ART in ALL HIV-positive patients regardless of CD4 count.START, 2015: immediate ART (any CD4) reduced serious AIDS events and death vs deferred treatment (CD4 < 350). SMART, 2006: ART interruptions increase mortality -never stop ART. HPTN 052, 2011: early ART reduces transmission by 96% (U=U). ACTG 076, 1994: zidovudine reduced vertical transmission 67.5% - foundation for PMTCT. Treat early, treat all.
Exception -delay ART in: cryptococcal meningitis (start ART 4–6 weeks after antifungal induction -early ART causes fatal IRIS) and TB meningitis (delay 2–8 weeks)
Rapid ART initiation (same day or within 7 days of diagnosis) is now recommended -improves linkage to care and viral suppression
Preferred Initial Regimen
Regimen
Components
Notes
Biktarvy PREFERRED
Bictegravir + emtricitabine + TAF (single pill, once daily)
Preferred first-line. High barrier to resistance, minimal drug interactions, well-tolerated. Renal/bone-safe (TAF > TDF).
Dovato
Dolutegravir + lamivudine (2-drug regimen)
Acceptable first-line if HBV-negative and viral load < 500,000. Not if HBV co-infected (needs 2 active HBV drugs).
Triumeq
Dolutegravir + abacavir + lamivudine
Alternative. Requires HLA-B*5701 testing before starting abacavir (risk of fatal hypersensitivity reaction if positive).
Occurs 2–12 weeks after starting ART -immune system "wakes up" and mounts an exuberant inflammatory response against pre-existing (often subclinical) infections
Unmasking IRIS: new OI symptoms appear after ART initiation (was subclinical before)
Paradoxical IRIS: known OI worsens after ART initiation despite appropriate treatment
Discontinue when CD4 >100 for ≥3 months on ART. Alternative: clarithromycin 500 mg BID.
Crypto maintenance
Fluconazole (Diflucan) 200 mg daily
After induction/consolidation for cryptococcal meningitis
Secondary prophylaxis. Discontinue when CD4 >200 for ≥6 months + undetectable VL.
📋 On Rounds
Why do you delay ART in cryptococcal meningitis?
COAT Trial, 2014: starting ART within 1–2 weeks of cryptococcal meningitis diagnosis increased mortality vs waiting 5–6 weeks. The mechanism: early immune reconstitution causes a massive inflammatory response in the CNS against cryptococci → cerebral edema → herniation → death.
When should you NOT start ART immediately after HIV diagnosis?
Cryptococcal meningitis is the main exception. Starting ART during active crypto meningitis causes immune reconstitution inflammatory syndrome (IRIS) → cerebral edema → herniation → death. The COAT trial showed early ART (within 1–2 weeks) had higher mortality than deferred ART (5 weeks after antifungal induction). Treat crypto first (amphotericin B + flucytosine × 2 weeks), then start ART at 4–6 weeks.
What are the 3 most important opportunistic infections to know by CD4 count?
Immune Reconstitution Inflammatory Syndrome (IRIS) = paradoxical clinical worsening after starting ART, caused by the recovering immune system mounting an inflammatory response against pre-existing (often subclinical) infections. Onset: usually 1-12 weeks after ART initiation. Common in: TB-IRIS (lymph node enlargement, worsening CXR), crypto-IRIS (increased intracranial pressure), MAC-IRIS (lymphadenitis), CMV-IRIS (vitritis). Management:Continue ART, do NOT stop unless life-threatening (CNS IRIS with herniation risk). Treat the underlying OI aggressively. Add corticosteroids (prednisone 1 mg/kg or dexamethasone) for moderate-severe IRIS, especially TB-IRIS with CNS involvement or crypto-IRIS with elevated ICP. Serial LPs for crypto-IRIS to control pressure. NSAIDs for mild symptoms. Treat TB and start ART early (within 2 weeks if CD4 < 50; 8 weeks if CD4 ≥ 50) to reduce IRIS risk per AHA/IDSA guidelines.
Case 1: New HIV Diagnosis, Rapid ART Start
Presentation: 28M presents to clinic after positive HIV screening. Asymptomatic. CD4 180, viral load 250,000 copies/mL. No prior ART. No active opportunistic infections on workup.
Assessment: New HIV diagnosis with CD4 < 200 (AIDS-defining) but no active OI. Candidate for rapid ART initiation (same-day start).
Plan:
• Start bictegravir/emtricitabine/TAF (Biktarvy), single pill, once daily, high barrier to resistance
• OI prophylaxis: TMP-SMX DS daily for PCP (CD4 < 200), also covers toxoplasmosis
• MAC prophylaxis not needed (CD4 > 50), would add azithromycin 1200 mg weekly if CD4 < 50
• Send baseline resistance genotype, HLA-B*5701, QuantiFERON, RPR, hepatitis B/C serologies, BMP, LFTs, fasting lipids
• Viral load at 4 weeks (expect > 1-log drop), then q3–6 months. Goal: undetectable (< 50 copies/mL) by 24 weeks
Key point: Rapid ART initiation (same day) improves linkage to care and viral suppression. Do not wait for genotype results, switch later if resistance detected.
Case 2: Immune Reconstitution Inflammatory Syndrome (IRIS)
Presentation: 35F started ART 3 weeks ago with baseline CD4 45, viral load 520,000. Now presents with worsening cervical lymphadenopathy, fevers to 39.2°C, and night sweats despite improving viral load (now 8,000 copies/mL).
Assessment: Paradoxical IRIS, clinical worsening despite virologic response to ART. Low baseline CD4 (< 50) is a major risk factor. Differential: TB-IRIS (most common cause of lymphadenopathy-predominant IRIS) vs unmasking of new opportunistic infection.
Plan:
• Continue ART, do NOT stop. Stopping ART worsens outcomes
• Workup: lymph node biopsy for AFB/culture/pathology, blood cultures for MAC, CXR, QuantiFERON, CrAg
• If TB-IRIS confirmed and severe (airway compromise, systemic toxicity): prednisone 1.5 mg/kg/day × 2 weeks then taper over 4 weeks
• NSAIDs for mild-moderate IRIS symptoms
• Monitor closely, IRIS is self-limited once immune reconstitution stabilizes
Key point: IRIS typically occurs 1–12 weeks after ART initiation, especially when baseline CD4 < 50. Continue ART. Steroids reserved for severe or life-threatening IRIS.
Case 3: ART Failure with Drug Resistance
Presentation: 42M on efavirenz/emtricitabine/TDF for 18 months. Reports good adherence but viral load persistently detectable at 4,200 copies/mL (was previously undetectable). CD4 stable at 310.
Plan:
• Switch to INSTI-based regimen: dolutegravir/emtricitabine/TAF, high barrier to resistance, once daily
• Adherence counseling, identify barriers (side effects, pill burden, social factors, substance use)
• Check full resistance panel including integrase resistance (especially if prior INSTI exposure)
• Repeat viral load at 4 weeks after switch, expect > 1-log drop
• If multi-class resistance: consult HIV specialist for salvage regimen construction
Key point: K103N is the most common NNRTI resistance mutation. Always obtain genotype before switching. Never add a single drug to a failing regimen, switch at least 2 active agents to avoid accumulating resistance.
📣 Sample Presentation
One-Liner
"Mr. Roberts is a 34-year-old newly diagnosed with HIV after presenting with PCP pneumonia. CD4 42, viral load 380,000. LDH 520, bilateral GGO on CT chest. Started on TMP-SMX for PCP."
Key Points to Cover on Rounds
New HIV diagnosis with AIDS-defining illness (PCP, CD4 42). Treatment: TMP-SMX 15-20 mg/kg/day (trimethoprim component) × 21 days + prednisone taper (PaO₂ <70). ART start timing: within 2 weeks of OI treatment (not day 1 -IRIS risk). Planned ART: bictegravir/emtricitabine/TAF. OI prophylaxis needed: PCP (already treating), MAC (azithro 1200 weekly if CD4 <50), toxo (TMP-SMX covers). Screening: QuantiFERON, RPR, hepatitis panel, Pap smear. Resistance genotype sent before starting ART.
Monitoring
Parameter
Frequency
Target / Notes
HIV viral load
At 4 weeks, then q3-6 months
Goal: undetectable (<50 copies/mL). Should suppress within 12-24 weeks of ART. Detectable VL → assess adherence, resistance testing.
CD4 count
q3-6 months until immune reconstitution
Guides OI prophylaxis. Discontinue monitoring once CD4 >300 ×2 and VL suppressed (CD4 no longer clinically actionable).
BMP, LFTs
Baseline, then q6-12 months
ART hepatotoxicity and nephrotoxicity. Tenofovir (TDF/TAF): monitor Cr, phosphate. TAF has less renal toxicity than TDF.
Fasting lipids, HbA1c
Baseline, then annually
Metabolic monitoring -HIV and ART increase cardiovascular risk. Protease inhibitors most lipid-unfriendly. Screen and treat per guidelines.
STI screening
At diagnosis, then annually (or more frequently if high-risk)
HPV-related malignancy risk increased. Cervical Pap for women. Anal Pap for MSM and history of anal dysplasia.
Resistance testing
At diagnosis + treatment failure
Genotype before starting ART. Repeat if VL rebounds on treatment (adherence must be assessed first).
⚡ Summary
Summary
Start ART in Everyone, Immediately
Regardless of CD4 count.START showed immediate treatment at any CD4 reduced serious AIDS events and death compared with deferring, and SMART showed treatment interruptions increase mortality. Same-day initiation improves linkage to care and viral suppression, so do not wait for the genotype; switch later if resistance is found.
Know the Preferred Backbone
An integrase strand transfer inhibitor plus two NRTIs, typically bictegravir/emtricitabine/tenofovir alafenamide or dolutegravir with tenofovir and emtricitabine. INSTIs are preferred for rapid viral suppression, a high barrier to resistance and few interactions.Check hepatitis B status before choosing, since tenofovir and emtricitabine also treat HBV and stopping them causes a hepatitis flare.
Prophylaxis Is Driven by the CD4 Count
CD4 below 200 is AIDS-defining and is where PJP prophylaxis starts, with TMP-SMX DS daily covering both PJP and toxoplasmosis. Below 50, add MAC consideration (largely superseded by prompt ART). Stop prophylaxis when CD4 is above 200 for at least 3 months on ART.
Treat the Opportunistic Infection First in Two Situations
Cryptococcal meningitis and tuberculous meningitis: delay ART by about 4 to 6 weeks, because starting early precipitates a CNS immune reconstitution response that kills. For most other opportunistic infections, start ART within 2 weeks, which improves survival.
Recognize IRIS Rather Than Calling It Failure
Paradoxical worsening 1 to 12 weeks after starting ART, most often when the baseline CD4 was below 50.Continue ART: the deterioration is a recovering immune system attacking a pre-existing organism, not treatment failure or a new infection. Steroids only for severe or life-threatening IRIS.
Never Add a Single Drug to a Failing Regimen
Get a genotype before switching, and change at least two active agents, because adding one drug to a failing regimen is functional monotherapy and accumulates resistance. K103N is the commonest NNRTI resistance mutation.Check adherence before assuming resistance: it is the far commoner cause of a rising viral load.
Screen for the Coinfections and the Interactions
Test for tuberculosis, hepatitis B and C, syphilis and other STIs at diagnosis, and vaccinate. Rifampin and antiretrovirals interact severely, so TB cotreatment needs dose adjustment or a rifabutin substitution. Review every new drug against the regimen, particularly acid-reducing agents and polyvalent cations, which block INSTI absorption and must be separated in time.
Do Not Interrupt ART in Hospital
Continue the home regimen through an admission wherever possible, and involve pharmacy to reconstruct it correctly, since partial regimens breed resistance within days. Monitor CD4 and viral load, expecting suppression within 3 to 6 months, and remember U=U: sustained undetectable viral load means the patient does not transmit sexually, which matters for counseling and for stigma.
Start in ALL patients. Preferred: bictegravir/emtricitabine/TAF (single pill, once daily). Get resistance genotype before starting. Goal: undetectable VL (< 50) by 6 months.
⚠️ IRIS
Paradoxical worsening 1-12 weeks after starting ART (immune reconstitution). Continue ART + treat OI aggressively. Steroids for severe IRIS. Don't stop ART.
💊 Key Drugs
Bictegravir/FTC/TAF1 tab daily
TMP-SMX DS1 tab daily (PCP/toxo)
Azithromycin1200 mg weekly (MAC)
Fluconazole200 mg daily (crypto maintenance)
⚠️ Pitfalls
Delaying ART initiation
Starting ART during active crypto meningitis (high IRIS risk -wait until CSF sterile)
Rodent-borne RNA virus causing two distinct syndromes: Hantavirus Pulmonary Syndrome (HPS) in the Americas (cardiopulmonary phenotype, 35–50% mortality) and Hemorrhagic Fever with Renal Syndrome (HFRS) in Eurasia (renal-dominant phenotype). Treatment is supportive; VA-ECMO is the only intervention shown to dramatically improve survival in HPS.
🔍 Overview
🚨 Active 2026 Outbreak (as of May 2026): An Andes virus outbreak on the cruise ship M/V Hondius (departed Ushuaia, Argentina, March 20, 2026 → Cabo Verde → Canary Islands). As of May 6, 2026: 5 confirmed + 3 suspected cases, 3 deaths (Dutch couple, German national). Symptoms onset April 6–28, 2026: fever, GI symptoms, rapid pneumonia → ARDS → shock. Three US passengers under monitoring (2 Georgia, 1 Arizona, all asymptomatic at last update).
Why this matters clinically: Andes is the only hantavirus with documented person-to-person transmission (respiratory droplets in close-contact settings). Maintain droplet/airborne precautions for any suspected case with recent South America travel or cruise-ship exposure. Sources: WHO Disease Outbreak News (DON599, May 2026); CDC Newsroom; CIDRAP.
Definition & Two Syndromes
Hantaviruses are single-stranded RNA viruses (Bunyavirales order, Hantaviridae family) carried by specific rodent reservoirs. Each virus species causes distinct disease depending on the host rodent and geography.
HPS (Hantavirus Pulmonary Syndrome)
HFRS (Hemorrhagic Fever with Renal Syndrome)
Region
Americas (New World hantaviruses)
Eurasia (Old World hantaviruses)
Major viruses
Sin Nombre virus (US, dominant), Andes virus (S. America), Bayou, Black Creek Canal, Choclo
Hantaan (severe, China/Korea), Dobrava (Balkans), Seoul (worldwide), Puumala (mild, Scandinavia/Europe)
Reservoir rodent
Deer mouse (Peromyscus maniculatus), cotton rat, rice rat (US); long-tailed pygmy rice rat (Andes virus, S. America)
Striped field mouse (Hantaan), bank vole (Puumala), brown rat (Seoul)
YES for Andes virus only (respiratory droplets, close-contact settings, household and healthcare). NO for Sin Nombre or other US strains.
NO for any HFRS-causing virus.
Epidemiology (HPS in the US)
~30–40 US cases per year, ~890 cumulative cases since CDC surveillance began in 1993, ~35% case-fatality rate.
~95% of cases west of the Mississippi. Highest incidence in Four Corners region (NM, AZ, CO, UT) where deer mouse populations are densest.
Recent US notable cases: Gene Hackman's wife Betsy Arakawa (Santa Fe, NM, February 2025); Mammoth Lakes, CA cluster (early–mid 2025).
Risk activities: cleaning out cabins, sheds, barns, garages with rodent infestation; camping in rodent-prone areas; rural occupations (farming, forestry, military field exercises).
2026 cruise-ship cluster (Andes virus, M/V Hondius) is unusual: ship-board transmission with documented person-to-person spread is a new pattern outside South American endemic regions.
Pathophysiology
Hantavirus infects vascular endothelium via β3-integrin receptor, especially pulmonary capillary endothelium (HPS) or renal/glomerular endothelium (HFRS).
Viral replication triggers a cytokine storm (IL-6, TNF-α, IFN-γ) and immune-mediated endothelial injury → capillary leak.
Why mortality is so high in HPS: the cardiopulmonary phase progresses over hours, often before diagnosis is made. Capillary leak resists fluid resuscitation (more fluid worsens pulmonary edema). The myocardial depression component reduces cardiac output independent of preload.
Clinical Phases of HPS
Phase
Duration
Features
Why It Matters
1. Prodromal
3–6 days
Fever, severe myalgias (especially thighs, hips, lower back), headache, nausea, vomiting, abdominal pain. Looks like flu or gastroenteritis.
Most missed phase. Dry cough or dyspnea is uncommon early. Diagnosis often made retrospectively.
2. Cardiopulmonary
Hours to a few days
Rapid-onset dyspnea, tachypnea, hypoxemia, pulmonary edema, refractory hypotension. CXR: bilateral interstitial → alveolar infiltrates ± pleural effusions. Often progresses to intubation in < 24h.
Lethal phase. Most deaths here. Distinguish from cardiogenic shock by echo (preserved EF). Distinguish from septic shock by lab triad (thrombocytopenia + hemoconcentration + immunoblasts).
If patient survives phase 2, recovery can be dramatic. Cautious volume management as fluid mobilizes.
4. Convalescent
Weeks to months
Persistent fatigue, exertional dyspnea, weakness.
Most survivors return to baseline.
Differential Diagnosis (in a patient with prodrome → respiratory failure)
Influenza, COVID-19, RSV, look-alike prodromes; hantavirus has more profound thrombocytopenia, hemoconcentration, and rapid progression to ARDS without typical respiratory prodrome.
Sepsis with ARDS, blood cultures, procalcitonin help; sepsis usually has a clear source.
Leptospirosis, also rodent contact, but causes biphasic illness with renal failure, jaundice, and conjunctival suffusion; treat empirically with doxycycline if exposure overlap.
Plague (pneumonic), rare but possible exposure overlap (rodents/fleas); rapid bacterial pneumonia + sepsis; covered by aminoglycosides or doxycycline.
Q fever, tularemia, similar zoonotic exposures, atypical pneumonia patterns.
Cardiogenic shock, echo with preserved EF rules out in HPS context.
🧪 Workup
Diagnostic Triad in HPS
Three-feature triad that should make you think hantavirus in any patient with prodrome → respiratory failure:
Thrombocytopenia (often < 100K, sometimes < 50K), present in > 90%.
Hemoconcentration (rising hematocrit from capillary leak losing intravascular fluid).
Immunoblasts on peripheral smear (> 10% atypical lymphocytes with abundant basophilic cytoplasm). Hand-counted smear, not flagged by automated CBC.
All three present in > 80% of HPS cases at presentation. Add exposure history (rodents, Four Corners, recent cruise/South America in 2026) → high pretest probability.
Laboratory
CBC with manual differential: thrombocytopenia, hemoconcentration (rising Hct), immunoblasts (atypical lymphocytes > 10%), often left shift.
BMP, Mg, phos: AKI common in HPS (less prominent than HFRS but present), hyperkalemia, lactic acidosis.
Hantavirus IgM and IgG by ELISA, sensitivity ~95% by the time cardiopulmonary phase begins (IgM positive almost always at admission; paired serology helps if early). Available through state public health labs and CDC.
RT-PCR for viral RNA from blood or tissue, useful in early infection before serology turns positive. CDC and reference labs.
Andes virus-specific testing if exposure history fits (recent South America, M/V Hondius, close contact with confirmed Andes case).
Notify public health immediately on suspicion, hantavirus is reportable in all US states.
Imaging & Bedside Tests
CXR: bilateral interstitial infiltrates (early) → alveolar infiltrates with perihilar predominance and Kerley B lines, ± pleural effusions. Looks like ARDS or cardiogenic edema.
Bedside echo: preserved or only mildly depressed EF (key discriminator from cardiogenic shock). May show small chamber size from preload depletion.
POCUS lung: B-lines bilaterally (non-specific for non-cardiogenic vs cardiogenic edema; combine with echo).
There Is No Specific Antiviral, This Is Supportive ICU Care
HPS kills via refractory shock + ARDS over hours. The interventions that move the needle: early ICU transfer, lung-protective ventilation, judicious fluid restriction (capillary leak resists volume), early vasopressors, and consideration of VA-ECMO at experienced centers, which has improved HPS survival from ~35% to ~50–65% in case series.
Step-by-Step Management
Step
Intervention
Why It Matters
1. Early ICU + isolation
Transfer to ICU at first sign of pulmonary involvement. Droplet + airborne precautions for any suspected Andes virus or undifferentiated case.
Decompensation is rapid (hours). Andes virus has documented person-to-person spread; standard hantavirus species do not, but until species is identified, full precautions are safer.
2. Lung-protective ventilation
Tidal volume 4–6 mL/kg ideal body weight, plateau pressure < 30 cmH₂O, PEEP titrated, FiO₂ to SpO₂ 88–94%. Prone if P/F < 150.
Avoid liberal crystalloid resuscitation. Target euvolemia or mild dryness. Use albumin in select cases (preserves oncotic pressure during capillary leak).
This is the pitfall. The instinct in shock is to give fluids; in hantavirus the capillary is leaking and more fluid worsens pulmonary edema while not raising BP. Pressors over volume.
4. Early vasopressors
Norepinephrine first-line, titrate to MAP ≥ 65. Add vasopressin 0.03 units/min if escalating. Epinephrine if myocardial component dominant.
Hypotension here is distributive + cardiogenic, not hypovolemic. Pressors restore perfusion without worsening pulmonary edema.
5. Consider VA-ECMO early
Refer to ECMO center if: refractory shock on 2+ pressors, refractory hypoxemia despite proning, cardiac index < 2.2, lactate rising. Do not wait for crash.
The single intervention that has moved HPS mortality from ~35% to ~50–65%. VA-ECMO bridges the patient through the cardiopulmonary phase (typically 3–7 days); diuretic phase begins and patient can be weaned.
6. Inotropic support if EF depressed
Epinephrine drip or milrinone (if SBP allows) for myocardial component.
HPS has a real myocardial depression component (immune-mediated myocarditis-like). Inotropes when EF is reduced.
7. Notify public health + isolate
Reportable disease in all US states. Andes virus exposure history → contact tracing.
Critical for outbreak control, especially Andes virus where person-to-person spread occurs.
8. Avoid corticosteroids for HPS
No proven benefit; may worsen viral replication.
Routine steroids are NOT supported by evidence. Reserve for refractory ARDS per standard ARDS protocols.
9. Ribavirin: NOT for HPS; YES for HFRS
HPS: ribavirin trials negative, do not use. HFRS: IV ribavirin (33 mg/kg load → 16 mg/kg q6h × 4d → 8 mg/kg q8h × 6d) reduces mortality if started within 7 days of onset.
This is a syndrome-specific distinction. Don't reflex ribavirin for HPS; it doesn't work. HFRS is the syndrome where it has documented benefit.
10. Renal support (HFRS >> HPS)
CRRT or HD for AKI with refractory hyperkalemia, volume overload, severe acidosis, or uremia.
HFRS often has prominent AKI requiring temporary dialysis. HPS has milder AKI usually.
11. Investigational
Convalescent plasma (case reports), Andes virus-specific monoclonal antibodies (in development as of 2026).
No standard-of-care role yet. Consider through clinical trial enrollment if available.
Infection Control (Andes Virus / Outbreak Setting)
For confirmed or suspected Andes virus (or any hantavirus pending species ID):
Single-patient room, negative-pressure if airborne procedures planned (intubation, bronchoscopy).
Droplet precautions (mask within 6 ft) + airborne precautions during aerosol-generating procedures (N95, eye protection).
Contact precautions (gown, gloves) for any patient contact.
Sin Nombre virus and other US strains: standard precautions sufficient (no documented person-to-person spread). But until species confirmed, treat as Andes-like.
💊 Medications
Medications Reference
Drug
Dose
Role
Notes
Norepinephrine FIRST-LINE
0.05–1 mcg/kg/min IV
Vasopressor for distributive/mixed shock
Titrate to MAP ≥ 65. Central access preferred. Peripheral OK as bridge.
Vasopressin
0.03 units/min IV (fixed)
Adjunct vasopressor
Add when escalating norepinephrine; spares catecholamine dose.
Epinephrine
0.05–1 mcg/kg/min IV
Inopressor when myocardial depression dominant
Useful when EF depressed and MAP low. Can cause tachyarrhythmias.
Milrinone
0.25–0.75 mcg/kg/min IV (no bolus typically)
Inotrope for myocardial depression with adequate BP
Avoid if hypotensive (vasodilator effect). Useful if cardiogenic component limits ECMO bridge.
Albumin 5%
250–500 mL IV PRN
Volume expander preserving oncotic pressure
Selective use during capillary leak; avoid liberal crystalloid.
Echo with EF significantly depressed (< 40%) in the cardiopulmonary phase
Why early: mortality without ECMO in patients meeting these criteria approaches 100%. With ECMO at experienced centers, ~50–65% survive. The diuretic phase typically arrives within 3–7 days of ECMO support.
🛡️ Prevention
Quick answer: Hantavirus is prevented by avoiding aerosolized rodent excreta. The highest-risk activity is sweeping or vacuuming a rodent-infested cabin, garage, or shed. Always wet down with bleach solution first, wear an N95 + gloves + eye protection, and never sweep dry. No vaccine is available in the US. For the 2026 Andes virus cruise outbreak, returning travelers should monitor for fever, severe muscle pain, and dyspnea for 6 weeks (incubation 7–42 days, typically 14–21).
How is hantavirus spread?
Hantaviruses are carried in the saliva, urine, and feces of infected rodents. Humans get infected by inhaling aerosolized virus when contaminated dust is stirred up (sweeping, vacuuming, disturbing nesting material). Less commonly, infection happens through:
Direct rodent contact, bites, scratches, or handling without gloves
Eating food contaminated with rodent excreta
Touching contaminated surfaces, then touching eyes, nose, or mouth
Person-to-person, only Andes virus (respiratory droplets in close-contact household and healthcare settings). All other hantaviruses, including Sin Nombre virus (the dominant US strain), do NOT spread between people.
Key reservoir species in the US: deer mouse (Peromyscus maniculatus) is the primary carrier of Sin Nombre virus, especially in the Four Corners region (New Mexico, Arizona, Colorado, Utah). Cotton rats, rice rats, and white-footed mice carry related strains.
How do I safely clean rodent droppings, urine, and dead rodents?
Never sweep or vacuum dry. This aerosolizes the virus directly into your breathing zone and is the most common cause of hantavirus infection.
CDC step-by-step cleanup method:
Ventilate first. Open all doors and windows for at least 30 minutes before entering. Leave the area while it ventilates. Why: this lets airborne virus particles disperse before you walk in.
Put on protective gear: N95 respirator (or higher), nitrile or rubber gloves, eye protection, long sleeves, closed shoes. A surgical mask is NOT adequate.
Mix a 1:10 bleach solution (1 part household bleach to 9 parts water = 10% bleach) OR an EPA-registered disinfectant labeled for viruses. Pour into a spray bottle.
Spray or pour disinfectant directly onto droppings, urine, and nesting material until thoroughly soaked. Let sit for at least 5 minutes. Why: contact time matters; bleach inactivates the virus on contact but needs the wet exposure.
Wipe up with paper towels or a damp cloth. Do not sweep, vacuum, or use a duster. Place all waste in a sealable plastic bag.
Disinfect the area again after wiping (sprayer or mop with bleach solution).
For dead rodents: spray the carcass and the surrounding area with disinfectant, soak for 5 minutes, place in a plastic bag, double-bag, and dispose in covered trash. Wash any traps with the same bleach solution.
Wash gloves before removing them, then wash hands thoroughly with soap and water for at least 20 seconds.
Wash any contaminated clothing in hot water and detergent.
Heavy infestation warning: If you find a heavily contaminated space (a long-vacant cabin, an attic with extensive nesting, a shed with dozens of droppings), do not clean it yourself. Hire a licensed pest-control service with PAPR (powered air-purifying respirator) capability. The risk of aerosolization in heavy infestations exceeds what an N95 alone protects against.
How do I rodent-proof my home, cabin, or outbuilding?
Hantavirus prevention starts with keeping rodents out of human-occupied spaces. The CDC's "Seal Up, Trap Up, Clean Up" framework:
1. Seal up entry points
Inspect the home exterior for openings 1/4 inch (6 mm) or larger. Mice can squeeze through gaps the size of a dime.
Seal gaps around pipes, utility cables, vents, and dryer outlets with steel wool plus caulk, or hardware cloth (1/4-inch mesh).
Repair gaps in foundations, siding, and door/window frames.
Install door sweeps. Why: most rodent entry happens at ground level under doors.
2. Trap up
Snap traps are preferred over glue traps and live traps. Why: glue traps don't kill quickly and stress the rodent (can promote viral shedding); live traps require handling the animal, which is high-risk.
Bait with peanut butter or oats; place along walls where rodents travel.
Check traps daily. Disinfect traps and rodent carcasses with the cleanup protocol above.
3. Clean up the food and shelter
Store all food (including pet food and birdseed) in rodent-proof metal or thick plastic containers with tight lids. Don't leave pet food bowls out overnight.
Wash dishes, clean counters, and store leftovers promptly.
Remove brush, woodpiles, junk, and abandoned vehicles from within 100 feet of the home. These are nesting sites.
Keep grass mowed short.
Elevate woodpiles and hay bales at least 1 foot off the ground.
How do I open a cabin or seasonal property safely?
Long-vacant cabins, hunting camps, and seasonal homes in the Four Corners region (New Mexico, Arizona, Colorado, Utah) are the highest-risk setting for US hantavirus. Before staying or cleaning:
Approach from outside. Open all doors and windows from outside before entering, then leave the cabin airing out for at least 30 minutes.
Inspect for evidence of rodents from the doorway: droppings, gnawed food packaging, nesting material, urine stains, dead rodents, mouse smell. Heavy evidence = call professionals.
Don and spray. If contamination is light to moderate and you'll clean yourself: N95, gloves, eye protection. Spray all visible droppings and nests with 10% bleach. Let sit 5 minutes.
Wet-wipe everything. Counters, floors, tabletops, the inside of drawers and cabinets. Discard exposed food.
Wash bedding, towels, and any cloth items in hot water before use.
Set traps for next time. Place snap traps along walls before you leave so the next visit starts cleaner.
Camping, hiking, and outdoor recreation
Avoid sleeping on bare ground in known rodent-active areas (mountain meadows, abandoned structures). Use a tent with a floor or hammock.
Don't disturb rodent burrows, dens, or nests.
Store food in rodent-proof containers (sealed bear canisters work, OdorBarrier sacks, or hung at least 12 ft up and 6 ft out from a tree branch).
Camp in clean, dry sites; avoid trash piles or evidence of rodent activity.
Never handle wild rodents, dead or alive.
2026 Andes virus outbreak: traveler precautions
If you traveled on the M/V Hondius cruise (Ushuaia, Argentina → Cabo Verde → Canary Islands, March–April 2026), or had close contact with anyone who did:
Self-monitor for symptoms × 6 weeks from last possible exposure (Andes virus incubation 7–42 days, typically 14–21).
Seek medical care immediately if you develop fever, severe muscle pain (especially thighs and lower back), nausea/vomiting, headache, or shortness of breath. Mention the cruise exposure, this changes diagnostic suspicion and treatment.
Avoid close contact with others if you become ill (Andes virus has documented person-to-person transmission via respiratory droplets, especially in household settings).
Notify your local public health department, hantavirus is reportable in all US states.
For South America travel in 2026 generally: the Andes virus is endemic to Argentina, Chile, Bolivia, and southern Brazil. Avoid abandoned buildings, brush areas, and food contaminated by rodents. Andes virus household clusters have been documented since the 1996 El Bolsón outbreak in Argentina.
No post-exposure prophylaxis exists. Early recognition is the only mitigation.
What should I do if I think I've been exposed?
Don't panic but don't ignore it. Most exposures don't cause infection; the attack rate after typical exposure is low. But hantavirus has no specific antiviral, so early recognition is critical.
Watch for symptoms over 6 weeks. Most cases present 14–21 days after exposure with fever, severe muscle aches (especially thighs, lower back, hips), headache, nausea, and vomiting. Cough and shortness of breath develop later (the cardiopulmonary phase, often days 4–7 of illness).
Seek emergency care for any of: shortness of breath, chest tightness, hypoxia, or rapid worsening. The cardiopulmonary phase progresses in hours; do NOT wait it out.
Tell the medical team about your exposure history, rodent contact, cabin cleaning, recent South America travel, M/V Hondius cruise, close contact with a confirmed case. This changes diagnostic suspicion and may save your life.
No vaccine is available in the US. Hantaan-virus vaccines are licensed in South Korea and China but not for Andes or Sin Nombre virus.
Frequently Asked Questions
Is hantavirus contagious between people?
Only the Andes virus strain (found in South America and on the M/V Hondius cruise ship in 2026) has documented person-to-person transmission via respiratory droplets in close-contact settings, especially household members and healthcare workers. All other hantaviruses, including Sin Nombre virus (the main US strain), are NOT contagious between people. Standard infection in the US comes from inhaling aerosolized rodent excreta.
How long after exposure do hantavirus symptoms appear?
Incubation is typically 14–21 days but can range from 1 week to 6 weeks (7–42 days). The first phase (prodrome) is fever, severe muscle aches in the thighs/back/hips, headache, nausea, and vomiting, lasting 3–6 days. The dangerous cardiopulmonary phase (cough, shortness of breath, low blood pressure) typically begins around days 4–7 of illness and can progress over hours.
Can you get hantavirus from a mouse bite?
Yes, but it's uncommon. Most US hantavirus cases come from inhaling aerosolized rodent excreta during cleaning or activity in infested spaces. Bites and scratches are a documented but rare route. If bitten by a wild rodent, wash the wound thoroughly, contact your healthcare provider, and monitor for symptoms for 6 weeks.
Can hantavirus be cured?
There is no specific antiviral cure for HPS (the cardiopulmonary form caused by Sin Nombre and Andes viruses). Treatment is supportive ICU care: lung-protective ventilation, vasopressors, and early VA-ECMO referral for severe cases (which improves survival from ~35% to 50–65% at experienced centers). For HFRS (the Eurasian renal-hemorrhagic form), IV ribavirin within 7 days of symptom onset reduces mortality. Ribavirin does not work for HPS.
Is there a hantavirus vaccine?
No vaccine is available in the United States. Inactivated Hantaan-virus vaccines are licensed in South Korea and China for the HFRS strains common there, but no vaccine targets Sin Nombre virus or Andes virus. Prevention relies entirely on rodent control, safe cleaning practices, and avoiding aerosolization.
Where is hantavirus most common in the United States?
~95% of US cases occur west of the Mississippi River, with the highest concentration in the Four Corners region (New Mexico, Arizona, Colorado, Utah) where deer mouse (Peromyscus maniculatus) populations are densest. Notable recent cases include Betsy Arakawa (Gene Hackman's wife, Santa Fe NM, February 2025) and the Mammoth Lakes, California cluster (2025). Total US cases since CDC surveillance began in 1993: ~890, with ~30–40 new cases per year.
What disinfectant kills hantavirus?
A 1:10 bleach solution (10% bleach in water) is the standard CDC recommendation for home cleanup. EPA-registered disinfectants labeled for "viruses" or "general use" are also effective. The key is contact time: spray or pour the disinfectant directly on droppings/urine/nesting material and let sit at least 5 minutes before wiping. Hantavirus is enveloped and is inactivated by bleach, alcohol-based disinfectants, and most commercial cleaners; UV light and drying also reduce viability over hours to days.
📋 On Rounds
On Rounds
📋 Sample Presentation
"Mr. Velasquez is a 42-year-old man with no significant PMH presenting with 4 days of fever, severe thigh and back myalgias, headache, and nausea, who developed acute dyspnea and hypoxia in the past 12 hours. He spent the prior weekend cleaning out his uncle's cabin in northern New Mexico, with visible mouse droppings. On arrival: SpO₂ 82% on RA, HR 130, BP 82/48. CXR shows bilateral perihilar interstitial infiltrates without cardiomegaly. Labs: platelets 62, Hct 52% (baseline 42), WBC 14 with 12% atypical lymphocytes (immunoblasts on smear), LDH 580, lactate 4.8, troponin mildly elevated, BNP 80. Bedside echo: preserved EF, small chamber size. We made the clinical diagnosis of Hantavirus Pulmonary Syndrome (most likely Sin Nombre virus given Four Corners exposure), sent hantavirus IgM/IgG and RT-PCR, and notified state public health. He was intubated for ARDS, started on lung-protective ventilation, norepinephrine for shock, and is being transferred to our ECMO center. Standard precautions only since US strains are not person-to-person transmitted."
Pimp Questions
What's the diagnostic triad for HPS on routine labs?
Thrombocytopenia + hemoconcentration + immunoblasts on peripheral smear, present in > 80% at presentation. Thrombocytopenia is often < 100K. Hemoconcentration (rising Hct) reflects intravascular fluid loss into tissues from capillary leak. Immunoblasts are atypical lymphocytes > 10% on hand-counted smear (auto-CBC misses them). Add the exposure history (rodents, Four Corners, recent South America/cruise in 2026) and pretest probability is high.
Why is fluid resuscitation a pitfall in HPS?
The capillary endothelium is leaking, so administered crystalloid moves into the alveolar space and worsens pulmonary edema without raising BP. The shock is distributive + cardiogenic, not hypovolemic. Use vasopressors (norepinephrine, vasopressin) rather than volume. Albumin selectively can preserve oncotic pressure. This is opposite to standard sepsis bundles, where 30 mL/kg is the reflex.
When does ribavirin work in hantavirus?
HFRS only, and only if started within 7 days of symptom onset. IV ribavirin (33 mg/kg load → 16 mg/kg q6h × 4d → 8 mg/kg q8h × 6d) reduces mortality in HFRS. Ribavirin does NOT work in HPS, multiple trials in the Americas were negative. Don't reflex ribavirin in HPS; treatment is supportive ICU care + early VA-ECMO consideration.
Which hantavirus strain has person-to-person transmission?
Andes virus is the only hantavirus with documented person-to-person transmission (respiratory droplets in close-contact household and healthcare settings). This is clinically relevant in 2026 because of the M/V Hondius cruise-ship outbreak (Andes virus, 5 confirmed + 3 suspected cases, 3 deaths as of May 6, 2026). All other hantaviruses, including Sin Nombre virus (the dominant US strain), are spread only via rodent excreta aerosolization. For undifferentiated hantavirus suspicion, use droplet + airborne precautions until species is identified.
How does VA-ECMO improve mortality in HPS?
VA-ECMO bridges the patient through the cardiopulmonary phase (typically 3–7 days), supporting cardiac output and oxygenation while the immune-mediated capillary leak and myocardial depression resolve. The diuretic phase then arrives and the patient can be weaned. Case series at experienced centers report HPS survival of 50–65% with ECMO vs 35% without. Refer early when patient meets criteria (refractory shock on 2+ pressors, P/F < 80, EF < 40%, lactate rising), do not wait for cardiac arrest.
Clinical Examples
📋 Case 1, Classic Sin Nombre HPS (US)
Patient: 42M, no PMH, cleaned out uncle's cabin in N. New Mexico last weekend (visible rodent droppings). 4 days of fever, severe thigh/back myalgia, GI symptoms; today acute dyspnea + hypoxia.
Norepinephrine + vasopressin (avoid liberal fluids, capillary leak)
Hantavirus IgM/IgG + RT-PCR sent; state public health notified
Empiric doxycycline (lepto coverage) + vanc/cefepime until cultures back
ECMO consult, transferred to ECMO center given P/F 70 and lactate rising
Standard precautions (US strain, no person-to-person spread)
Teaching point: Four Corners + cabin cleaning + prodrome with severe myalgias + thrombocytopenia + immunoblasts = HPS until proven otherwise. Treatment is supportive ICU + early ECMO referral.
📋 Case 2, Andes Virus from 2026 Cruise Ship
Patient: 56F, 14 days post-disembarkation from M/V Hondius cruise (Ushuaia → Cabo Verde, March–April 2026). 5 days of fever and GI symptoms, now acute dyspnea.
Key findings: SpO₂ 86% RA, plt 48, Hct rising, immunoblasts present, lactate 5.2. CXR: bilateral infiltrates. Wife (close household contact during voyage) also developed mild fever.
Single-patient negative-pressure room; N95 + eye protection for staff
Andes virus-specific RT-PCR (CDC); standard hantavirus serology
State + CDC + WHO public health notification (international outbreak)
Wife isolated and monitored for symptom development × 6 weeks
Supportive care as in Case 1; early ECMO referral
Teaching point: 2026 outbreak alert. Recent South America travel or M/V Hondius itinerary + hantavirus syndrome → Andes virus suspect → airborne/droplet precautions + contact tracing of close contacts. Person-to-person spread is unique to Andes among hantaviruses.
📋 Case 3, HFRS (Eurasian Hantavirus)
Patient: 34M military service member, recently returned from field exercise in South Korea. Presents with 5 days of fever, severe lumbar/flank pain, and now oliguria.
ICU monitoring; aggressive renal support (CRRT/HD as needed for AKI/hyperK)
IV ribavirin 33 mg/kg load → 16 mg/kg q6h × 4d → 8 mg/kg q8h × 6d (HFRS, day 5 of symptoms, within 7-day window)
Hantaan / Dobrava / Seoul serology + RT-PCR
Watch for hemorrhagic complications (retroperitoneal/GI bleed)
Vasopressors as needed; cautious fluids
Teaching point: HFRS is the Eurasian phenotype: renal-dominant + hemorrhagic. Ribavirin works here if started within 7 days of onset, unlike HPS where it is ineffective. Travel history (Korea, China, Russia, Balkans, Scandinavia) plus AKI + thrombocytopenia + hemorrhagic features = consider HFRS.
🎯 Summary
At a Glance
Two Syndromes
HPS (Americas, cardiopulmonary, 35-50% mortality) vs HFRS (Eurasia, renal-hemorrhagic, 0.1-15% mortality). The geography tells you which organ will fail, and therefore what to prepare for: an ICU bed and possible ECMO for HPS, dialysis capability for HFRS.
2026 Outbreak
Andes virus on M/V Hondius cruise (Ushuaia → Cabo Verde → Canary Islands, March-April 2026). 5 confirmed + 3 suspected, 3 deaths as of May 6, 2026. Person-to-person spread documented.This is why a travel and cruise history matters: Andes is the one hantavirus that transmits between people, so the exposure question changes the isolation decision.
US Epidemiology
~30-40 cases/year, ~95% west of the Mississippi, Four Corners predominant. ~890 cumulative cases since 1993. Sin Nombre virus dominant. It is rare enough that it is only diagnosed by clinicians who ask about rodent exposure, which is the question that puts it on the differential at all.
Transmission
Aerosolized rodent excreta, classically while sweeping or cleaning a cabin, shed or crawl space. Person-to-person ONLY for Andes virus (respiratory droplets, close contact). Every other strain poses no risk to staff, which is what makes the strain question practical rather than academic.
Diagnostic Triad
Thrombocytopenia + hemoconcentration + immunoblasts on smear, in a patient with a prodrome progressing to respiratory failure plus rodent or cruise exposure. The hemoconcentration is the giveaway: capillary leak drives plasma out of the vasculature, so a rising hematocrit alongside a falling platelet count in a febrile patient is the pattern that separates it from ordinary pneumonia.
Phases of HPS
Prodrome (3-6 d, flu-like) → cardiopulmonary (hours, lethal) → diuretic (1-2 d, recovery) → convalescent. The transition from prodrome to cardiopulmonary phase is abrupt, so a patient who looks like influenza can be in shock within hours. That is the argument for early ICU transfer rather than ward observation.
Imaging Clues
CXR bilateral interstitial → alveolar infiltrates with perihilar predominance. Echo: preserved EF. The preserved ejection fraction distinguishes it from cardiogenic shock, and that matters because the treatments are opposite: this patient needs fluid restriction and pressors, not inotropes and diuresis for pump failure.
Treatment
Supportive ICU. ARDSnet ventilation. Restrict fluids, because the problem is capillary leak and volume loading floods the alveoli. Norepinephrine + vasopressin. Early VA-ECMO (50-65% survival vs 35% without), so refer before multiorgan failure sets in. Ribavirin: HFRS only, NOT HPS, where it has shown no benefit.
Isolation
Andes virus or undifferentiated: airborne + droplet + contact precautions.Sin Nombre and other US strains: standard precautions sufficient (no person-to-person spread).Default to full precautions until the strain and exposure are established, because de-escalating later costs nothing and the reverse cannot be undone.
Reportable
All US states. Notify state public health on suspicion, not on confirmation, since case-finding and rodent-exposure investigation depend on early notification. International outbreak (Andes virus): WHO + CDC notification, plus contact tracing, which is unnecessary for the non-transmissible strains.
RoundsRx Infographic Series · #186 · Sepsis & Infection · PDF 141 KB
Text version
Hantavirus One-Pager
2026 alert: Andes virus outbreak on M/V Hondius cruise (Ushuaia, Argentina → Canary Islands). Person-to-person transmission documented. Suspect in any returned passenger or close contact with prodrome → respiratory failure.
Diagnose clinically + confirm with serology/PCR:
Exposure: rodents (US, Four Corners) OR South America / cruise / close contact with Andes case
Prodrome 3–6 days: fever, severe thigh/back myalgia, GI symptoms
Early ICU + airborne/droplet precautions (until species ID'd)
ARDSnet ventilation (6 mL/kg PBW), prone if P/F < 150
Restrict fluids (capillary leak, more fluid worsens edema)
Norepinephrine + vasopressin first; epinephrine or milrinone for myocardial component
Refer for VA-ECMO early if refractory shock, P/F < 80, EF < 40%, lactate rising
Empiric doxycycline (lepto) + broad-spectrum antibiotics until cultures back
Ribavirin for HFRS only within 7 days of onset; NOT for HPS
Notify public health (reportable)
Andes virus: contact tracing of close contacts × 6 weeks
Avoid: liberal crystalloid resuscitation (worsens pulmonary edema), corticosteroids routinely (no benefit), ribavirin for HPS (ineffective), waiting for crash before ECMO referral.
Sources for 2026 outbreak data: WHO Disease Outbreak News (DON599, May 2026); CDC Newsroom; CIDRAP. Clinical content per CDC HPS clinical guidance, IDSA emerging infections updates, and published case series on VA-ECMO outcomes.
A filovirus causing severe viral hemorrhagic fever with case-fatality 25 to 90% by species. The intern’s job is recognition, isolation, and calling the right people. Aggressive supportive care saves lives independent of any drug. Inmazeb, Ebanga, and Ervebo are Zaire-ebolavirus-only, the active 2026 outbreak is Bundibugyo virus, so the approved drugs do not apply.
🔍 Overview
🚨 Active 2026 Outbreak (PHEIC declared May 17, 2026): Ebola disease caused by Bundibugyo ebolavirus in the Democratic Republic of the Congo (DRC) and Uganda. As of May 26, 2026: DRC has 121 confirmed cases (17 deaths) plus 1,077 suspected cases (238 deaths) in Ituri, North Kivu, and South Kivu provinces. Uganda has 7 confirmed cases (1 death). Two suspected travel-related cases in Lombardy, Italy (returning from Uganda) tested negative on May 25, 2026.
Why this is clinically critical: Inmazeb (atoltivimab/maftivimab/odesivimab), Ebanga (ansuvimab), and the Ervebo (rVSV-ZEBOV-GP) vaccine are all approved for Zaire ebolavirus only. Against Bundibugyo, none of them are indicated. Supportive care is the entire toolkit for the current outbreak strain. Sources: WHO Disease Outbreak News (May 2026); ECDC; CDC Travel Health Notices.
What Ebola is
Ebola virus disease (EVD) is a severe, often fatal illness caused by viruses in the Filoviridae family (same family as Marburg). Five species infect humans, with different geography and lethality. Transmission is by direct contact with body fluids (blood, vomit, diarrhea, saliva, breast milk, semen, sweat) of a symptomatic case or recently-deceased body, or with contaminated surfaces and fomites. Not airborne under standard conditions. Incubation is 2 to 21 days (most 8 to 10).
The Five Species (and Why It Matters at the Bedside)
Species
Geography
Case Fatality
Approved MCM
Approved Vaccine
Zaire ebolavirus
DRC, West Africa (2014–16 epidemic), most US-imported cases
40–90% (untreated); ~28–35% with MCM + supportive care
None approved. cAd3-EBO-S and ChAd3-SUDV candidates deployed under trial protocols during outbreaks.
None approved.
Bundibugyo ebolavirus2026 OUTBREAK
DRC, Uganda (2007, 2012, 2026)
25–50%
None approved. Investigational MCMs case-by-case via NIH/CDC; cross-reactivity of Zaire-targeted antibodies is incomplete and not a substitute.
None approved.
Tai Forest ebolavirus
Côte d’Ivoire (single human case, 1994)
Single survivor
None approved.
None approved.
Reston ebolavirus
Philippines, China (in non-human primates and swine)
No human disease documented
Not applicable
Not applicable
Why this table matters: the species drives whether any species-specific drug is even on the menu. If a returning traveler from DRC or Uganda in 2026 presents with Ebola, the working assumption is Bundibugyo until species-confirmed, and the medication shelf is empty. Supportive care is the proven backbone. Reaching for Inmazeb in a Bundibugyo case is not just unhelpful, it can delay supportive interventions and falsely reassure the team.
Transmission
Direct contact with body fluids of a symptomatic case (blood, vomit, diarrhea, saliva, semen, breast milk, sweat, urine) or with corpses (funeral practices are a major outbreak amplifier in endemic regions).
Fomites: needles, bedding, exam gloves, environmental surfaces contaminated by body fluids. Virus persists hours to days on surfaces depending on conditions.
Healthcare-associated transmission is the dominant pattern in hospital outbreaks, driven by inadequate PPE and high-risk procedures (suctioning, intubation, dialysis, post-mortem handling).
Sexual transmission from male survivors documented up to 12+ months post-recovery (semen RT-PCR can remain positive for >1 year). Breast milk and ocular fluid also harbor persistent virus.
Not airborne in routine clinical settings. Aerosol-generating procedures (intubation, BiPAP, open suctioning, CPR) can produce infectious droplet nuclei, which is why those procedures require enhanced PPE and ideally a negative-pressure room.
Patients are not contagious before symptom onset, which is the basis for 21-day contact monitoring rather than blanket isolation.
Clinical Phases
Phase
Days
Features
Why It Matters
1. Early febrile (“dry”)
Days 1–3
Abrupt fever, severe fatigue, myalgia, headache, sore throat, conjunctival injection. Looks like flu or malaria.
Most cases get missed here. Travel history within 21 days is the single most important screening question. Pretest probability is everything.
2. GI (“wet”)
Days 3–10
Severe vomiting, profuse watery diarrhea (5–10 L/day), abdominal pain, anorexia, hiccups. Maculopapular rash in ~25% (often missed on darker skin).
This is where supportive care saves lives. Hypovolemic shock and electrolyte derangements (hypokalemia, hypomagnesemia, hypocalcemia) are the proximate killers, not the virus itself. IV fluids and electrolyte repletion are the highest-yield interventions.
Hemorrhage is not universal and not required for diagnosis. The classic “hemorrhagic fever” image is overstated, most patients die from shock and multi-organ failure, not exsanguination.
4. Recovery or death
Days 8–16
Death typically days 8–16. Survivors enter prolonged convalescence with fatigue, arthralgias, uveitis, hearing loss, neurocognitive symptoms.
Post-Ebola syndrome is real and underrecognized. Survivors need ophthalmology, audiology, and mental health follow-up; CNS, ocular, and genital tract are sanctuary sites where virus can persist.
When to Suspect (Triage Red Flags)
Suspect Ebola if BOTH:
Clinical: fever ≥38°C OR any compatible symptom (severe headache, myalgia, vomiting, diarrhea, abdominal pain, unexplained bleeding).
Exposure within 21 days: travel to or residence in an active Ebola outbreak country (currently DRC, Uganda); OR contact with a known/suspected Ebola case; OR contact with body fluids of a sick or deceased person in an outbreak area; OR direct handling of bats, non-human primates, or bushmeat in endemic regions; OR work in a lab handling filoviruses.
If both are present: STOP. Mask the patient, place them in a private room with the door closed, alert charge nurse and infection control before further workup.
Differential Diagnosis in a Febrile Returning Traveler
Malaria (Plasmodium falciparum), by far the most common cause of febrile illness in returning travelers from sub-Saharan Africa, and the most likely diagnosis even when Ebola is on the differential. Always rule out malaria first with thick and thin smears or rapid diagnostic test, even before Ebola PCR. Missed falciparum kills within 24 hours.
Other viral hemorrhagic fevers: Marburg (filovirus, same family, same PPE), Lassa (West Africa, rat-borne, distinct epidemiology), Crimean-Congo (tick-borne, Eurasia/Africa), severe dengue (Asia, Latin America).
Meningococcemia, petechiae or purpura fulminans, requires immediate ceftriaxone.
Acute HIV seroconversion, viral hepatitis (A, B, E), measles, also on the list for nonspecific febrile illness.
🧪 Workup
The CDC Framework: Identify, Isolate, Inform
This is the entire intern playbook. Three steps, in order, before any other workup.
Identify, screen every febrile patient at triage for travel history and exposure within 21 days. One question added to triage is the difference between a contained case and a hospital outbreak.
Isolate, immediately to a single room with private bathroom (or dedicated commode), door closed, dedicated equipment, sign-in log. Limit entries to essential personnel only. Mask the patient. PPE for anyone entering (see Prevention tab).
Inform, in this order: charge nurse → hospital infection control / hospital epidemiologist → state or local health department → CDC Emergency Operations Center 770-488-7100 (24/7).
What NOT to Do Until Cleared
Until the patient is risk-stratified and public health has guided next steps:
No routine venipuncture or blood draws, every blood-handling step is an exposure. Only essential labs for clinical decision-making (malaria smear, basic chemistries, CBC), drawn by experienced staff in proper PPE, processed in a sealed transport container, lab notified in advance.
No central lines, no arterial lines, no LP, no surgery unless absolutely life-saving. Every needle stick is a potential transmission event.
No aerosol-generating procedures (intubation, BiPAP, open suctioning, nebulizers, bronchoscopy) without enhanced PPE and a negative-pressure room.
No transport for imaging until cleared. Bedside chest X-ray and ultrasound only.
No moving the patient through public spaces. No family visits. No food trays in and out without containment.
Laboratory Workup (Once Approved)
Ebola RT-PCR from EDTA whole blood, the gold standard. Run through the Laboratory Response Network (LRN) via the state public health lab, never the routine hospital lab. RT-PCR can be falsely negative within the first 72 hours of symptoms, repeat at 72 hours from symptom onset if initial test is negative and clinical suspicion persists. PCR sensitivity is >95% once symptomatic for >72 hours.
Malaria thick and thin smears AND malaria RDT, mandatory and immediate. A returning traveler with fever has falciparum until proven otherwise.
CBC with differential, leukopenia early then leukocytosis with left shift, thrombocytopenia (often <100K), lymphopenia.
BMP, Mg, Phos, ionized Ca, profound electrolyte derangements drive the morbidity. Track every 6–12 hours during the wet phase.
LFTs, AST > ALT (often 5–10× ULN), suggests hepatocellular injury and is a useful severity marker. Bilirubin often only mildly elevated.
Coags + fibrinogen + D-dimer, DIC pattern in severe disease (prolonged PT/aPTT, low fibrinogen, very high D-dimer).
Blood cultures × 2, gram-negative bacteremia from gut translocation is common and treatable; do not skip just because you suspect Ebola.
Pregnancy test in any woman of reproductive age, EVD in pregnancy is nearly uniformly fatal to the fetus and risk to mother is high; changes counseling and obstetric coordination.
Type and screen, HIV, hepatitis serologies, anticipate transfusion needs and confirm baseline status.
Imaging and Bedside Tests
Bedside CXR, usually unremarkable early; ARDS pattern if pulmonary involvement or fluid overload from over-resuscitation.
Bedside ultrasound (POCUS), IVC for volume status, lungs for B-lines, FAST for free fluid in the abdomen if hemorrhage suspected. POCUS minimizes patient movement and exposure.
ECG, baseline QTc before any QT-prolonging antiemetics or antibiotics; myocarditis can occur.
Risk Stratification by CDC Exposure Tier
Tier
Definition
Action
High risk
Percutaneous or mucous-membrane exposure to body fluids of a confirmed case; unprotected direct contact with a corpse in an outbreak area; lab handling without proper PPE.
Direct active monitoring × 21 days. Confine movement. Public health-supervised isolation if symptomatic.
Some risk
Household contact with confirmed case; direct contact with case while wearing PPE; healthcare worker in an outbreak setting with PPE breaches.
Active monitoring × 21 days. Restricted travel. Symptom-triggered isolation.
Low (but not zero) risk
Travel from outbreak country without specific contact; brief direct contact (e.g., handshake) with a symptomatic case while wearing PPE.
Passive self-monitoring × 21 days with reporting to public health if febrile.
No identifiable risk
Travel from non-outbreak countries adjacent to affected areas; contact with asymptomatic person who later tested negative.
No restrictions.
🩺 Management
Cornerstone: aggressive supportive care drops mortality from ~50% toward 25% even without any species-specific drug. This is true for every Ebola species. The intern’s leverage is on volume, electrolytes, glucose, and infection control, not on chasing a monoclonal antibody.
Volume Resuscitation
Balanced crystalloid (LR or Plasma-Lyte) IV, large volumes are often needed during the wet phase (losses of 5–10 L/day). Match output plus insensible losses. Avoid normal saline alone in large volumes, the chloride load worsens an already-deranged acid-base picture (hyperchloremic acidosis on top of lactic acidosis from shock).
Strict I/O, with hourly nursing assessment during the wet phase. Daily weights when feasible.
Oral rehydration (WHO ORS) is the global standard when IV access is unavailable; in US ICUs, IV is faster but ORS still has a role in stable patients with persistent diarrhea.
Avoid fluid overload, capillary leak makes pulmonary edema easy to precipitate in late disease. Re-assess with POCUS, do not just keep bolusing.
Electrolyte and Metabolic Repletion
Hypokalemia, replete to K ≥4.0 mEq/L; oral KCl preferred when tolerated to limit invasive lines. Hypomagnesemia coexists and must be corrected first or potassium will not stay in (renal wasting in the presence of low Mg).
Hypocalcemia, hypomagnesemia, hypophosphatemia, frequent and severe with massive GI losses. Check ionized calcium, not just total.
Hypoglycemia, common, especially in pediatric and malnourished patients; check glucose every 4–6 hours, treat with D10 or D50 IV depending on severity.
Acidosis, lactic acidosis from shock, anion-gap acidosis from AKI, hyperchloremic from NS over-use; fix the perfusion problem, not the bicarbonate number. Bicarb infusion only if pH <7.1 with hemodynamic compromise.
Hemodynamic Support
Norepinephrine first-line vasopressor for shock unresponsive to volume. Target MAP ≥65.
Vasopressin as second agent if escalating norepinephrine.
Stress-dose hydrocortisone (50 mg IV q6h) if catecholamine-refractory shock, same SSC 2026 logic as any septic shock.
Avoid invasive lines until PUI status is clarified. When a central line is unavoidable, ultrasound-guided single-pass attempt by the most experienced operator, dedicated sharps disposal at the bedside, never recap a needle.
Bleeding Management (if Present)
Hemorrhage occurs in ~20% of cases and is rarely the immediate cause of death; do not let “hemorrhagic fever” framing distract from the bigger threats (shock, electrolytes, AKI).
Transfusion thresholds, same as any critically ill patient: Hb 7 g/dL (TRICC/TRISS), platelets <10K prophylactic or <50K with active bleeding, FFP and cryoprecipitate guided by INR / fibrinogen.
Tranexamic acid 1 g IV in active hemorrhage with hemodynamic compromise, extrapolated from CRASH-2.
DIC pattern is common in late disease, treat the underlying virus and shock, transfuse to clinical bleeding rather than chasing numbers.
Symptom Control
Antiemetics, ondansetron 4–8 mg IV q8h, watch QTc (already at risk in shock and electrolyte chaos). Metoclopramide is a backup.
Antidiarrheals, loperamide is controversial because of theoretical concerns about retained virus; in practice WHO and CDC permit it for severe diarrhea once infectious gastroenteritis (C. diff, Salmonella) is excluded.
Fever and pain, scheduled acetaminophen. Avoid NSAIDs and aspirin, they worsen AKI and amplify bleeding risk in DIC. Opioids cautiously for severe pain.
Anxiety, delirium, low-dose haloperidol or quetiapine; benzodiazepines second-line and avoid in hemodynamically unstable patients.
Species-Specific Monoclonal Antibodies
⚠️ Critical species caveat: the two FDA-approved Ebola monoclonal antibodies, Inmazeb and Ebanga, are licensed only for Zaire ebolavirus. They are not indicated and are not expected to work for Sudan, Bundibugyo, Tai Forest, or Reston ebolaviruses. For the 2026 Bundibugyo outbreak, neither drug is on the menu.
Drug
Composition
Dose
Indication
Evidence
Inmazeb (REGN-EB3)
Cocktail of three human monoclonal antibodies (atoltivimab, maftivimab, odesivimab) targeting Ebola glycoprotein
50 mg/kg of each component (150 mg/kg total) IV ×1
Zaire ebolavirus only, adults and pediatric including neonates born to Ebola-positive mothers
PALM, 2019 reduced 28-day mortality to 33.5% vs 49.7% with ZMapp
Ebanga (ansuvimab, mAb114)
Single human monoclonal antibody against Ebola glycoprotein, derived from a 1995 Kikwit survivor
50 mg/kg IV ×1
Zaire ebolavirus only, adults and pediatric including neonates
PALM, 2019 28-day mortality 35.1%, comparable to Inmazeb
Both monoclonals work best when given early, mortality benefit is strongest in patients with lower viral loads at presentation. Do not delay supportive care while arranging drug access.
How to access: in the US, both are stockpiled by HHS / BARDA and released through the Strategic National Stockpile during an outbreak. Coordinate via state health department and CDC EOC; do not call the pharmacy expecting it on the shelf.
For Sudan, Bundibugyo, Tai Forest, no approved MCM. Investigational antibodies (e.g., MBP134 cross-reactive cocktail) may be available case-by-case under expanded access via NIH/CDC; supportive care remains the proven intervention.
Remdesivir and ZMapp are no longer recommended for Ebola, both were inferior to Inmazeb and Ebanga in PALM, do not substitute for the licensed drugs.
Empiric Co-Infection Coverage
Empiric anti-malarial, artemether-lumefantrine or IV artesunate based on severity, until smear and RDT are negative. Falciparum kills faster than Ebola in the first 48 hours and is treatable.
Empiric broad-spectrum antibiotics, ceftriaxone 2 g IV daily covers gram-negative bacteremia from gut translocation, common in advanced EVD. Add vancomycin if line infection suspected. Continue 5–7 days or until cultures clarify.
Antifungal coverage not routine; consider if prolonged broad-spectrum antibiotic exposure or invasive lines.
Complications to Watch
AKI, from volume depletion, direct viral cytopathy, and pigmenturia (myoglobin, hemoglobin). Daily renal function. Renal replacement therapy (CRRT preferred over intermittent HD because of hemodynamic instability) for refractory acidosis, volume overload, or uremia.
ARDS, from over-resuscitation, capillary leak, or aerosol exposure. Lung-protective ventilation (TV 6 mL/kg PBW, plateau ≤30, prone if P/F <150) per ARDSNet and PROSEVA.
Myocarditis, troponin elevation and depressed EF can occur; supportive, no specific therapy.
Hepatitis, AST > ALT, transaminases often 5–10× ULN; supportive.
Late: post-Ebola syndrome, fatigue, arthralgia, headache, mood disturbance, hearing loss, uveitis, all reported in survivors months to years out. Ophthalmology follow-up at 1 month is the bedside high-yield recommendation, uveitis can cause irreversible vision loss.
Persistent virus in sanctuary sites, eye humor, CSF, semen, breast milk. Documented sexual transmission from male survivors up to 12+ months out, counsel safer sex and serial semen RT-PCR until two consecutive negatives.
🛡️ Prevention
PPE for Ebola: Layered, Not Standard
Standard isolation PPE is not enough. Ebola PPE is full-body coverage with no skin exposed and a buddy-supervised donning and doffing protocol. The doffing step is where most healthcare-worker infections happen, not direct patient care.
Respiratory: PAPR (powered air-purifying respirator) preferred for aerosol-generating procedures; fitted N95 + full face shield acceptable for routine care. Surgical mask is not enough.
Body: impermeable coverall or gown PLUS a separate fluid-resistant apron over the gown, surgical hood covering head and neck.
Hands: double gloves (inner glove tucked under sleeve, outer glove over cuff).
Feet: waterproof knee-high boots or boot covers over closed-toe shoes.
Trained observer, a second trained person watches every donning and every doffing, reads the checklist out loud, calls out breaches in real time.
Doffing area, designated dedicated space immediately outside the patient room, with ABHR (alcohol-based hand rub) and waste containment at each step.
Limit personnel, the more people in the room, the more exposure events. Cohort one nurse and one MD per shift when possible; no trainees, no observers, no rotating teams.
Vaccine: Ervebo (rVSV-ZEBOV-GP)
FDA-approved single-dose live-attenuated vaccine using vesicular stomatitis virus expressing Ebola Zaire glycoprotein. Approved for ages ≥18 in 2019, expanded to ≥12 in July 2023.
Protects against Zaire ebolavirus only. Does not protect against Sudan, Bundibugyo, Tai Forest, or Reston. For the 2026 Bundibugyo outbreak, Ervebo is not the answer.
Efficacy: Guinea ring vaccination trial (2015) showed 100% protection at ≥10 days post-vaccination against Zaire, real-world effectiveness ~84–97% in DRC outbreaks.
Used as: (1) pre-exposure for frontline workers in outbreak countries (healthcare staff, contact tracers, lab personnel, burial teams) and surrounding high-risk countries (Uganda, Rwanda, South Sudan, Burundi); (2) post-exposure ring vaccination around confirmed Zaire cases (~10 days to protection).
For Sudan ebolavirus, no approved vaccine. Candidate vaccines (Sabin’s cAd3-EBO-S, IAVI’s ChAd3-SUDV) deployed under clinical-trial protocols during Sudan outbreaks (e.g., Uganda 2022, 2025).
For Bundibugyo, no approved or trial-ready vaccine; supportive care plus PPE plus contact tracing are the entire prevention toolkit for the 2026 outbreak.
Contact Tracing and Ring Vaccination
Identify all contacts within 21 days of the case’s symptom onset. Categorize by exposure tier (see Workup tab).
Daily symptom check × 21 days from last exposure, looking for fever ≥38°C, severe headache, GI symptoms, unexplained bleeding.
Ring vaccination, vaccinate contacts and contacts-of-contacts around each confirmed Zaire case. Highly effective. Not applicable to Bundibugyo, no approved vaccine.
Active vs passive monitoring, high and some-risk tiers get direct public-health observation; low-risk tiers self-monitor with daily reporting.
Returning Traveler Counseling
21-day vigilance after return from an outbreak country. Any febrile illness within 21 days → seek medical care immediately and call ahead, so the clinic or ED can mask and isolate before arrival. Walking unannounced into a waiting room is the single biggest amplifier of healthcare exposure.
Avoid travel to active outbreak areas, check CDC Travel Health Notices before any sub-Saharan Africa travel.
Healthcare workers and aid workers returning from outbreak areas, pre-arranged active monitoring with state public health; clear plan for symptom-triggered isolation and testing.
Survivors, safer sex (condoms) or abstinence until two consecutive negative semen RT-PCRs at least one week apart, typically 12+ months post-recovery for men. Breastfeeding mothers, defer breastfeeding until milk RT-PCR negative.
Environmental and Waste Decontamination
Surfaces, EPA-registered hospital disinfectant with label claim against non-enveloped viruses (Ebola is enveloped and easier to kill, but use the higher bar to be safe). 1:10 bleach solution acceptable for spills.
Waste, Category A infectious substance, requires specialized packaging and transport per 49 CFR. Do not put Ebola waste in routine medical waste bins.
Linens, single-use disposable preferred; if reusable, autoclave or incinerate.
Sharps, dedicated puncture-resistant container at the bedside, sealed and labeled when full, hand-carried to disposal by trained staff.
📋 Rounds
Pimp Questions
What two pieces of information do you need to suspect Ebola at triage?
(1) Compatible clinical syndrome, fever ≥38°C OR any compatible symptom (headache, myalgia, vomiting, diarrhea, abdominal pain, unexplained bleeding). (2) Exposure within 21 days, travel to or residence in an active outbreak country (currently DRC, Uganda in 2026), contact with a known case, body-fluid contact with sick or deceased in an outbreak area, or lab handling. Both required to trigger the Identify-Isolate-Inform pathway.
Why don’t Inmazeb and Ebanga work for the 2026 outbreak?
Both are Zaire-ebolavirus-only. The 2026 outbreak in DRC and Uganda is caused by Bundibugyo ebolavirus, a different species. Inmazeb (a 3-antibody cocktail) and Ebanga (ansuvimab) target the Zaire glycoprotein and have no proven activity against Bundibugyo. Reaching for them in a Bundibugyo case is not just unhelpful, it can delay supportive interventions and create false reassurance. Supportive care is the proven backbone regardless of species.
What kills patients with Ebola?
Not hemorrhage. Most deaths are from hypovolemic shock and electrolyte derangements driven by 5 to 10 L/day of GI losses during the wet phase, plus multi-organ failure (AKI, ARDS, hepatitis, myocarditis). Visible bleeding occurs in only ~20%. The bedside lever is aggressive fluid resuscitation, electrolyte and glucose repletion, and infection control, not chasing the “hemorrhagic fever” framing.
A returning traveler from Uganda has fever. What test do you order first?
Malaria thick and thin smears plus rapid diagnostic test. Falciparum malaria is by far the most common cause of febrile illness in returning sub-Saharan Africa travelers and kills within 24 hours if missed. Ebola PCR comes after isolation is in place and malaria is being addressed in parallel. Always rule out malaria first.
Why is doffing PPE the highest-risk step?
Most healthcare-worker Ebola infections occur during PPE removal, not direct patient care. Contaminated gloves and gowns transfer virus to skin and mucous membranes through small breaches in sequence (touching the face, snagging the gown, removing the mask before the gloves). Mitigation: a trained observer reads the doffing checklist out loud, in a designated doffing area with hand rub at each step. Buddy system is non-negotiable.
Who do you call (and in what order)?
Charge nurse → hospital infection control / hospital epidemiologist → state or local health department → CDC Emergency Operations Center 770-488-7100 (24/7). Public health authorizes testing through the LRN, never the routine hospital lab. Do not draw routine labs until guidance is given.
Sample Intern Scenario, Day-1 Cross-Cover
2 a.m. page from the ED: “Hi, we have a 34-year-old man, returned from Kampala 5 days ago, came in with fever 38.9°C, vomiting, watery diarrhea ×2 days. He’s in fast-track right now. Can you come down?”
What you do in the next 5 minutes:
Stop the patient from moving. Ask the ED to mask him, place him in a private room with the door closed (any private room is better than fast-track). No more visitors. No more staff in/out.
Page charge nurse and ED attending, confirm the exposure history with the patient directly (Uganda travel within 21 days? contact with sick person? handling animals?).
Page hospital infection control immediately. They activate the institution’s Special Pathogens Response Team or equivalent.
State health department, then CDC EOC 770-488-7100.
Order malaria smear and RDT (single dedicated draw with full PPE), and start empiric artemether-lumefantrine if any delay in smear results.
No central line, no LP, no routine labs until cleared. Bedside POCUS for volume status, peripheral IV by experienced nurse, IV fluids LR via syringe pump in sealed administration set.
Document exposure list, every staff member who has touched or been within 1 m of the patient since arrival, with timestamp. This is the contact-tracing dataset if the case turns positive.
The wrong move is to draw a CBC, BMP, blood cultures, and an ABG in the first 10 minutes “just to get them done”. Every needle stick before PPE and infection control are in place is a potential transmission event.
📌 Summary
EBOLA AT A GLANCE
Family: Filoviridae. Five species: Zaire, Sudan, Bundibugyo, Tai Forest, Reston. Case fatality 25–90% by species.
Transmission: direct contact with body fluids of symptomatic cases or corpses. Not airborne under standard conditions. Patients are not contagious before symptom onset (basis for 21-day contact monitoring).
Incubation: 2–21 days (most 8–10).
Phases: early febrile (days 1–3) → wet/GI (days 3–10) → critical/shock (days 7–12) → recovery or death (days 8–16).
Suspect if: fever or compatible symptom AND exposure within 21 days (travel to outbreak country, contact with case, body fluids in outbreak area, lab handling).
Rule out malaria first in returning sub-Saharan Africa traveler. Falciparum kills faster than Ebola in the first 48 hours.
Supportive care is the backbone: aggressive volume (LR, not large-volume NS), strict electrolyte and glucose repletion, norepinephrine for shock, empiric antimalarial and broad-spectrum antibiotics for co-infection.
Species-specific drugs (Zaire only): Inmazeb (50 mg/kg of each of 3 antibodies IV ×1), Ebanga (50 mg/kg IV ×1). 28-day mortality dropped to ~33–35% in PALM 2019.
No approved drug or vaccine for Sudan, Bundibugyo, Tai Forest, Reston. 2026 Bundibugyo outbreak: supportive care is the entire toolkit.
PPE: PAPR or N95 + face shield, double gloves, impermeable coverall + apron, hood, knee-high boots. Trained observer. Doffing is the highest-risk step.
Vaccine Ervebo (rVSV-ZEBOV-GP): single dose, ages ≥12, Zaire only. Used as pre-exposure for frontline workers and as post-exposure ring vaccination around Zaire cases.
Survivors: virus persists in semen, eye humor, breast milk, CSF. Safer sex / abstinence until two consecutive negative semen RT-PCRs. Ophthalmology follow-up for uveitis at ~1 month.
RoundsRx Infographic Series · #186 · Sepsis & Infection · PDF 141 KB
Text version
Infectious Disease · One Pager
Ebola Virus Disease
The intern's job is recognition, isolation, and calling the right people. Aggressive supportive care saves lives independent of any drug, and for the 2026 Bundibugyo outbreak it is the entire toolkit.
🚨 Identify, Isolate, Inform
Suspect if BOTH: (1) fever ≥38°C OR any compatible symptom (severe headache, myalgia, vomiting, diarrhea, abdominal pain, unexplained bleeding), AND (2) exposure within 21 days: travel to or residence in an active outbreak country (currently DRC, Uganda), contact with a known or suspected case, contact with body fluids of a sick or deceased person in an outbreak area, handling bats, non-human primates, or bushmeat, or lab work with filoviruses
Identify: screen every febrile patient at triage for travel and exposure within 21 days. One added triage question is the difference between a contained case and a hospital outbreak
Isolate: mask the patient, single room with private bathroom or dedicated commode, door closed, dedicated equipment, sign-in log, entries limited to essential personnel
Inform, in this order: charge nurse → hospital infection control / hospital epidemiologist → state or local health department → CDC Emergency Operations Center 770-488-7100 (24/7)
Transmission: direct contact with body fluids of a symptomatic case or a recently deceased body, plus fomites. Not airborne under standard conditions. Patients are not contagious before symptom onset, which is why contacts are monitored for 21 days rather than isolated outright
Incubation: 2 to 21 days, most 8 to 10
⛔ What NOT to Do Until Cleared
No routine venipuncture or blood draws. Every blood-handling step is an exposure. Only essential labs for clinical decisions (malaria smear, basic chemistries, CBC), drawn by experienced staff in proper PPE, sealed transport container, lab notified in advance
No central lines, arterial lines, LP, or surgery unless life-saving, because every needle stick is a potential transmission event
No aerosol-generating procedures (intubation, BiPAP, open suctioning, nebulizers, bronchoscopy) without enhanced PPE and a negative-pressure room
No transport for imaging. Bedside chest X-ray and ultrasound only
No moving the patient through public spaces, no family visits, no food trays in and out without containment
The wrong move is drawing a CBC, BMP, cultures, and an ABG in the first 10 minutes "just to get them done"
💉 Supportive Care: The Actual Treatment
1
Rule out malaria first: thick and thin smears AND rapid diagnostic test, mandatory and immediate. Falciparum is the most common cause of fever in a returning sub-Saharan Africa traveler and kills faster than Ebola in the first 48 hours. Start empiric artemether-lumefantrine, or IV artesunate by severity, if results are delayed
2
Volume, with balanced crystalloid (LR or Plasma-Lyte): wet-phase losses run 5 to 10 L/day, so match output plus insensible losses. Avoid large-volume normal saline, the chloride load stacks hyperchloremic acidosis on top of the lactic acidosis of shock
3
Electrolytes and glucose: replete K to ≥4.0 mEq/L, but correct magnesium first or potassium will not stay in (renal wasting when Mg is low). Check ionized calcium, not total. Glucose q4 to 6h, hypoglycemia is common, treat with D10 or D50 by severity
4
Shock: norepinephrine first-line for volume-unresponsive shock, target MAP ≥65; vasopressin as the second agent; stress-dose hydrocortisone 50 mg IV q6h if catecholamine-refractory. Avoid fluid overload, capillary leak makes pulmonary edema easy to precipitate, so reassess with POCUS instead of reflex bolusing
5
Cover co-infection: ceftriaxone 2 g IV daily for gram-negative bacteremia from gut translocation, common in advanced disease, 5 to 7 days or until cultures clarify. Add vancomycin if line infection is suspected
6
Symptom control: ondansetron 4 to 8 mg IV q8h with QTc awareness, scheduled acetaminophen for fever and pain, and avoid NSAIDs and aspirin because they worsen AKI and amplify bleeding risk in DIC
💊 Species-Specific Drugs (Zaire Only)
Inmazeb (REGN-EB3)50 mg/kg of each of 3 antibodies (150 mg/kg total) IV ×1
Ebanga (ansuvimab, mAb114)50 mg/kg IV ×1
Ervebo (rVSV-ZEBOV-GP) vaccinesingle dose, ages ≥12, Zaire only
All three are Zaire-ebolavirus-only. The active 2026 outbreak is Bundibugyo, so none of them apply and supportive care is the entire toolkit
Both monoclonals work best given early, the mortality benefit is strongest at lower viral loads, but never delay supportive care to chase drug access
Access: stockpiled by HHS / BARDA and released through the Strategic National Stockpile, coordinated via state health department and CDC EOC. It is not on the hospital pharmacy shelf
No approved drug or vaccine for Sudan, Bundibugyo, Tai Forest, or Reston. Investigational antibodies case-by-case via NIH/CDC
Remdesivir and ZMapp are no longer recommended, both were inferior in PALM
📊 Monitoring and Labs
Ebola RT-PCR from EDTA whole blood through the Laboratory Response Network via the state public health lab, never the routine hospital lab. It can be falsely negative within the first 72 hours of symptoms, so repeat at 72 hours from onset if suspicion persists; sensitivity is >95% once symptomatic >72 hours
BMP, Mg, Phos, ionized Ca every 6 to 12 hours during the wet phase, because the electrolyte derangements are what drive the morbidity
CBC: leukopenia early then leukocytosis with left shift, thrombocytopenia (often <100K), lymphopenia
LFTs: AST > ALT, often 5 to 10× ULN, a useful severity marker; bilirubin usually only mildly up
Coags, fibrinogen, D-dimer for the DIC pattern of severe disease, plus lactate, troponin, CK as end-organ markers
Blood cultures × 2, do not skip them just because you suspect Ebola, gram-negative bacteremia is common and treatable
Pregnancy test in any woman of reproductive age, it changes counseling and obstetric coordination
Bedside POCUS (IVC for volume, lungs for B-lines, FAST if hemorrhage suspected) because it minimizes patient movement and exposure. Baseline ECG for QTc before QT-prolonging drugs
⚠️ Pitfalls
Reaching for Inmazeb in a Bundibugyo case. Not just unhelpful, it delays supportive interventions and falsely reassures the team
Letting "hemorrhagic fever" framing drive the plan. Bleeding occurs in only ~20% and is rarely the immediate cause of death; shock, electrolytes, and multi-organ failure are
Missing the case in the dry phase (days 1 to 3), when it looks like flu or malaria. Travel history within 21 days is the single most important screening question
Trusting a negative PCR drawn in the first 72 hours. Repeat it
Skipping the malaria workup because Ebola is the exciting diagnosis
Over-resuscitating into ARDS. Capillary leak in late disease makes pulmonary edema easy to cause
Putting Ebola waste in routine medical waste bins. It is a Category A infectious substance requiring specialized packaging and transport per 49 CFR
🧥 PPE: Layered, Not Standard
Standard isolation PPE is not enough. Full-body coverage with no skin exposed, plus a buddy-supervised donning and doffing protocol
Respiratory: PAPR preferred for aerosol-generating procedures; fitted N95 plus full face shield acceptable for routine care. A surgical mask is not enough
Body: impermeable coverall or gown PLUS a separate fluid-resistant apron over it, and a surgical hood covering head and neck
Hands: double gloves, inner glove tucked under the sleeve, outer glove over the cuff
Feet: waterproof knee-high boots or boot covers over closed-toe shoes
Trained observer watches every donning and doffing, reads the checklist out loud, and calls out breaches in real time, because doffing is where most healthcare-worker infections happen, not direct patient care
Designated doffing area immediately outside the room with alcohol-based hand rub and waste containment at each step
Limit personnel: cohort one nurse and one MD per shift when possible. No trainees, no observers, no rotating teams, since every extra person is another exposure event
🎓 Key Evidence and Numbers
PALM, 2019: Inmazeb cut 28-day mortality to 33.5% vs 49.7% with ZMapp; Ebanga 35.1%. This is what made both drugs standard for Zaire
Supportive care alone drops mortality from ~50% toward 25%, without any species-specific drug, in every species
Case fatality 25 to 90% by species: Zaire 40 to 90% untreated (~28 to 35% with MCM plus supportive care), Sudan 40 to 60%, Bundibugyo 25 to 50%
Ervebo efficacy: Guinea ring vaccination trial (2015) showed 100% protection at ≥10 days post-vaccination against Zaire, real-world effectiveness ~84 to 97% in DRC outbreaks
Phases: early febrile days 1 to 3, wet/GI days 3 to 10, critical/shock days 7 to 12, recovery or death days 8 to 16
Survivors: virus persists in semen, ocular fluid, breast milk, and CSF. Safer sex or abstinence until two consecutive negative semen RT-PCRs at least one week apart, typically 12+ months. Ophthalmology follow-up at ~1 month, since uveitis can cause irreversible vision loss
Coccidian parasite spread by fecal-contaminated fresh produce and water. Causes prolonged, relapsing, watery diarrhea with profound fatigue, anorexia, and weight loss. Routine stool ova-and-parasites misses it, so you must specifically request Cyclospora testing. TMP-SMX is the only reliably effective treatment, and there is no good alternative for sulfa-allergic patients.
🔍 Overview
🚨 Active 2026 US Outbreak (as of July 2026): CDC issued a Health Alert Network notice for a surge in domestically acquired cyclosporiasis. Since May 1, 2026, CDC has logged 4,173 laboratory-confirmed domestic cases plus more than 7,400 additional probable cases still under investigation, a case count outpacing the prior season by more than 6-to-1. A linked traceback investigation identified 1,645 confirmed cases across 34 states (age range 2 to 95, median 44, 56% female).
Source and recall: The traceback points to shredded iceberg lettuce (Taylor Farms de Mexico) served at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia. On July 17, 2026, Taylor Farms de Mexico recalled all iceberg lettuce sourced from central Mexico.
Why this matters clinically: Suspect cyclosporiasis in any patient with prolonged (more than 1 week) or relapsing watery diarrhea, especially with a fresh-produce exposure. Standard stool ova-and-parasites (O&P) does not detect Cyclospora, so the diagnosis is missed unless you order it specifically. Sources: CDC HAN (HAN00531, 2026); CDC Cyclosporiasis Outbreak Investigation (July 2026); Infection Control Today, 2026.
What Is It
Cyclospora cayetanensis is a single-celled coccidian protozoan parasite (same broad family as Cryptosporidium and Cystoisospora). It infects the small-bowel epithelium and causes a prolonged, self-limited but often debilitating diarrheal illness in immunocompetent hosts, and a more severe, protracted illness in the immunocompromised.
Transmission & Why Outbreaks Happen
Fecal-oral, via contaminated food or water, not directly person-to-person. Freshly passed oocysts are not immediately infectious: they need days to weeks in the environment to sporulate (mature). This is why direct person-to-person spread does not occur, and why hospital contact precautions beyond standard hygiene are not required.
Classic vehicles are fresh produce that is eaten raw and can hold onto oocysts: leafy greens (iceberg/romaine lettuce), fresh herbs (cilantro, basil), raspberries, blackberries, snow peas, and mesclun. The 2026 US outbreak is lettuce-linked.
Seasonality: US cases cluster in spring and summer (May through August), which is why an outbreak in July fits the expected pattern.
Washing does not reliably remove it. Oocysts adhere tightly to produce surfaces and are resistant to routine chlorine and sanitizer washes, so ordinary rinsing cannot be relied on to make contaminated produce safe (see Prevention).
Clinical Course (the pattern that gives it away)
Incubation is a median of ~7 days (range roughly 2 to 14 days) after ingestion, longer than most bacterial foodborne illness, so patients often cannot pin it to a single meal.
Watery, non-bloody diarrhea is the hallmark, often frequent and profuse.
Relapsing / remitting course is highly characteristic: patients improve, then relapse. Untreated illness commonly lasts several weeks and can persist a month or more, which is why it is a leading cause of prolonged traveler's and foodborne diarrhea.
Profound anorexia, fatigue, and weight loss are disproportionate to a "simple" gastroenteritis and are a useful clue.
Other features: abdominal cramping, bloating, marked flatulence, nausea, low-grade fever, and myalgias.
Immunocompromised (advanced HIV, transplant): more severe, voluminous, and protracted diarrhea; biliary tract involvement (acalculous cholecystitis) can occur.
🧪 Workup
The single most important teaching point: a routine stool ova-and-parasites (O&P) exam does NOT detect Cyclospora. The lab must be specifically asked to look for it (special stains or a molecular GI panel that includes Cyclospora). If you do not order it by name, a negative "O&P" falsely reassures you and the diagnosis is missed.
When to Suspect
Watery diarrhea lasting more than ~1 week, or a relapsing diarrheal course, in an otherwise immunocompetent patient. Prolonged duration is the key trigger, since most bacterial and viral gastroenteritis resolves in days.
Fresh-produce or contaminated-water exposure, restaurant/outbreak link, or travel to an endemic region (Latin America, South/Southeast Asia).
Diarrhea plus disproportionate fatigue, anorexia, and weight loss.
Diagnostic Tests
Test
What it shows / why it works
Notes
Molecular multiplex GI PCR panel
Most sensitive and fastest. Several FDA-cleared gastrointestinal pathogen panels include Cyclospora cayetanensis. Detects parasite DNA directly.
PREFERRED where available Increasingly the first-line test; does not depend on catching oocysts on a slide.
Oocysts are 8 to 10 μm (about twice the size of Cryptosporidium, ~4 to 6 μm). They are variably acid-fast: in the same field, oocysts range from unstained to light pink to deep red.
Requires the lab to be told to look; not part of a routine O&P.
UV autofluorescence microscopy
Oocysts autofluoresce blue-green under ultraviolet epifluorescence against a dark background. Rapid and sensitive screening method.
Sensitive but not specific; confirm with stain or molecular test.
Stool wet mount / O&P
Standard parasite exam. Insensitive for Cyclospora and easily missed.
DOES NOT rule it out A negative routine O&P does not exclude cyclosporiasis.
Collect More Than One Specimen
Oocysts are shed intermittently and at low levels, even in patients with profuse diarrhea. A single negative stool does not exclude the diagnosis. If clinical suspicion is high and the first specimen is negative, collect at least 2 to 3 stool specimens on different days and process them with a sensitive method (molecular panel or special stains). This is the same reason a single sample under-detects the parasite in outbreak surveillance.
Supporting Labs
CBC: eosinophilia is not typical (unlike many helminths), so a normal eosinophil count does not argue against it.
BMP: assess for dehydration and electrolyte loss from prolonged diarrhea.
Consider co-testing for other stool pathogens; Cyclospora can co-occur with other foodborne organisms in an outbreak setting.
💊 Management
Treatment Approach
Antiparasitic therapy: TMP-SMX (trimethoprim-sulfamethoxazole) is the treatment of choice. It is the only reliably effective agent. Untreated illness is prolonged and relapsing, so treating shortens the course and prevents relapse rather than just easing symptoms.
Rehydration and supportive care: oral rehydration for most; IV fluids if volume-depleted from profuse or prolonged diarrhea. Replace electrolytes as needed.
Immunocompromised patients need more: higher doses, longer duration, and often long-term secondary suppression (see Medications), because relapse is common once therapy stops.
Public health reporting: cyclosporiasis is a nationally notifiable condition. Report confirmed and suspected cases to your state or local health department, especially during the current outbreak, so traceback and recalls can proceed.
Response and follow-up: On TMP-SMX, symptoms typically begin improving within a few days. If diarrhea does not improve after completing therapy, reconsider the diagnosis, check for a co-infection, and consider immunocompromise (which warrants a longer course). Persistent or recurrent symptoms in an immunosuppressed patient are an indication for extended treatment plus suppressive therapy.
What NOT to Do
Do not rely on a routine O&P to exclude it before treating a compatible prolonged/relapsing diarrhea, order the specific test.
Do not expect antibacterial "traveler's diarrhea" regimens to cover it. Azithromycin and standard fluoroquinolone empiric dosing are not reliable Cyclospora therapy; the parasite needs TMP-SMX.
Do not stop antiparasitic therapy early in the immunocompromised, relapse is the rule without an adequate course and suppression.
💉 Medications
Drug Regimens
Agent
Dose & Duration
Role / Why
TMP-SMX (Bactrim/Septra) DS 1ST LINE
1 double-strength tablet (TMP 160 mg / SMX 800 mg) PO twice daily × 7 to 10 days (immunocompetent adults and children over 2 months). Pediatric: TMP 5 mg/kg / SMX 25 mg/kg PO BID.
The only reliably effective agent. 7 to 10 days covers the full course and prevents the characteristic relapse; shorter courses risk recurrence.
TMP-SMX (immunocompromised)
Higher dose / longer course during acute illness, then secondary suppression: 1 DS tablet PO 3 times weekly while immunosuppressed (e.g., advanced HIV until immune reconstitution).
Immunosuppressed patients relapse without prolonged therapy and maintenance suppression, mirroring the approach used for other coccidian parasites in HIV.
Nitazoxanide (Alinia) SULFA ALLERGY
500 mg PO twice daily × 7 days (adult).
Considered for true sulfa allergy, but evidence is limited and efficacy is inconsistent. No alternative matches TMP-SMX.
Ciprofloxacin SULFA ALLERGY
500 mg PO twice daily × 7 days (adult).
Second-line for sulfa-allergic patients. Less effective than TMP-SMX with slower symptom resolution; use when nitazoxanide is unavailable or fails.
Sulfa allergy is the hard problem: CDC states that no highly effective alternative has been identified for patients who cannot take a sulfonamide. Nitazoxanide and ciprofloxacin are the fallback options, both less reliable than TMP-SMX. For a documented, non-severe sulfa reaction, weigh the benefit of the far more effective TMP-SMX against the allergy history, and involve allergy/ID when the illness is severe or prolonged.
🛡️ Prevention
Food & Water Safety
Washing produce reduces but does not eliminate risk. Cyclospora oocysts stick tightly to produce and resist routine chlorine/sanitizer washing, so rinsing cannot be relied on to make contaminated produce safe. During an active outbreak, avoiding the implicated product is the only reliable measure.
During the 2026 outbreak: follow CDC/FDA advisories, avoid recalled iceberg lettuce (Taylor Farms de Mexico, central-Mexico sourced), and heed restaurant-specific warnings.
Cooking kills the parasite; the risk is from raw/fresh produce. When in doubt in a high-risk period, cooked produce is safe.
Travelers to endemic regions should follow safe food and water practices (avoid raw produce and untreated water) during spring/summer months when transmission peaks.
Public Health
Report cases. Cyclosporiasis is nationally notifiable; prompt reporting lets public health link cases, identify the food vehicle, and trigger recalls that stop the outbreak.
No person-to-person precautions beyond standard hygiene are needed in the hospital, because freshly shed oocysts are not infectious until they sporulate in the environment. Standard hand hygiene is sufficient.
No vaccine exists; prevention is entirely food/water safety and outbreak avoidance.
🩺 Rounds
Pimp Questions
A patient has 12 days of watery diarrhea and a negative stool O&P. Why might the O&P be falsely negative, and what do you order?
Routine O&P does not detect Cyclospora, which requires specific testing: a modified acid-fast stain, UV autofluorescence, or a molecular GI PCR panel that includes Cyclospora. Oocysts are also shed intermittently, so collect 2 to 3 specimens on different days. A single negative routine O&P never excludes cyclosporiasis in a compatible prolonged/relapsing diarrhea.
What is the treatment of choice for cyclosporiasis, and the dose?
TMP-SMX (trimethoprim-sulfamethoxazole). Immunocompetent adults: 1 DS tablet (160/800 mg) PO BID × 7 to 10 days. It is the only reliably effective agent. The 7 to 10 day course prevents the classic relapse. Immunocompromised patients need higher/longer dosing plus suppressive therapy (1 DS tablet 3×/week).
Your patient has a true sulfa allergy. What are the options and the caveat?
Nitazoxanide 500 mg PO BID × 7 days or ciprofloxacin 500 mg PO BID × 7 days. The caveat: no highly effective alternative exists, both are less reliable than TMP-SMX (cipro is slower and less effective; nitazoxanide evidence is limited and inconsistent). For a mild sulfa reaction with severe illness, TMP-SMX may still be preferred after weighing risk.
How does Cyclospora spread, and does it require contact isolation in the hospital?
Fecal-oral via contaminated food or water (fresh produce), not person-to-person. Freshly passed oocysts are non-infectious until they sporulate over days to weeks in the environment. So no special contact precautions are needed beyond standard hand hygiene, and household/hospital transmission from a patient does not occur.
How do you distinguish Cyclospora from Cryptosporidium on a modified acid-fast stain?
Size. Cyclospora oocysts are 8 to 10 μm, roughly twice the diameter of Cryptosporidium (~4 to 6 μm). Cyclospora is also variably acid-fast (oocysts stain unevenly from unstained to deep red in the same field) and autofluoresces blue-green under UV. Molecular GI panels distinguish them definitively.
Clinical Examples
📋 Case 1, Outbreak-linked prolonged diarrhea
Patient: 44F, healthy, presents with 10 days of frequent watery, non-bloody diarrhea that briefly improved then relapsed. Marked fatigue, anorexia, and 5-lb weight loss. Ate at a fast-food restaurant with shredded lettuce ~1 week before onset.
Key findings: Afebrile to low-grade fever, mild orthostasis, no eosinophilia. Initial routine stool O&P negative. Local outbreak of cyclosporiasis reported.
Management:
Ordered Cyclospora-specific testing (molecular GI panel) rather than trusting the negative O&P
Molecular panel positive for Cyclospora cayetanensis
TMP-SMX DS 1 tab PO BID × 7 to 10 days + oral rehydration
Reported to the local health department (outbreak traceback)
Teaching point: Prolonged/relapsing watery diarrhea + fresh-produce exposure + negative routine O&P is the classic trap. Order the specific test and treat with TMP-SMX.
📋 Case 2, Sulfa-allergic patient
Patient: 52M with documented sulfonamide allergy (prior urticaria), 2 weeks of relapsing watery diarrhea, weight loss, confirmed Cyclospora on molecular panel.
Management:
Cannot use first-line TMP-SMX given allergy history
Started nitazoxanide 500 mg PO BID × 7 days; counseled that response may be incomplete
Ciprofloxacin 500 mg PO BID × 7 days held as backup if no improvement
Close follow-up arranged given the lack of a highly effective non-sulfa option
Teaching point: There is no equal substitute for TMP-SMX. Nitazoxanide or ciprofloxacin are fallbacks, and the patient needs follow-up because response is less reliable.
📋 Case 3, Immunocompromised host
Patient: 39M with advanced HIV (CD4 40), profuse, voluminous, protracted watery diarrhea for over 3 weeks, dehydration, RUQ discomfort.
Key findings: Cyclospora confirmed; ultrasound suggests acalculous cholecystitis (biliary involvement can occur in advanced immunosuppression).
Management:
Higher-dose, longer-course TMP-SMX for acute illness
Secondary suppression (1 DS tablet PO 3×/week) until immune reconstitution on ART
Aggressive rehydration and electrolyte repletion
Start/optimize antiretroviral therapy, immune recovery is the durable fix
Teaching point: In advanced immunosuppression, cyclosporiasis is severe and relapsing. Treat longer and maintain suppression until CD4 recovers.
🎯 Summary
At a Glance
Organism
Cyclospora cayetanensis, a coccidian protozoan parasite of the small bowel. It invades the enterocytes of the jejunum, which is why the illness is a malabsorptive watery diarrhea with profound fatigue rather than a dysenteric one.
2026 Outbreak
US surge, 4,173 confirmed + 7,400 probable since May 1, 2026 (CDC HAN). Traceback: shredded iceberg lettuce (Taylor Farms de Mexico) at Taco Bell in IN, KY, MI, OH, WV. Recall July 17, 2026. Ask about fresh produce and restaurant exposure in the preceding 2 weeks, because the incubation period means the meal that caused it is long forgotten by the time the patient presents.
Transmission
Fecal-oral via contaminated fresh produce and water.NOT person-to-person, because oocysts must sporulate in the environment for days before becoming infectious. That single fact means no isolation is needed and household contacts are not at risk from the patient, only from the same food source.
Incubation
Median ~7 days, range ~2 to 14, which is longer than most bacterial foodborne illness. The long incubation is why the exposure history has to reach back two weeks and why clusters are recognized late, after the implicated produce has already been eaten widely.
Hallmark
Prolonged, relapsing watery non-bloody diarrhea with marked fatigue, anorexia and weight loss. Untreated it runs for weeks to a month or more.The relapsing course is characteristic: patients improve, are told it was a virus, then relapse, which is often what finally prompts testing.
Diagnosis
Routine ova and parasites MISSES it.You must order specific testing: molecular GI panel (preferred), modified acid-fast stain, or UV autofluorescence. Oocysts are 8 to 10 µm. A negative routine O&P is the commonest reason this diagnosis is delayed by weeks, because everyone assumes the parasite screen covered it.
Multiple Specimens
Shedding is intermittent, so collect 2 to 3 stools on different days.One negative result does not exclude it, and in a patient with the classic relapsing course a single negative should prompt repeat sampling rather than a different diagnosis.
Treatment
TMP-SMX DS 1 tablet PO BID for 7 to 10 days.It is the only reliably effective agent, and it prevents the relapse that characterizes untreated infection. Symptoms usually improve within a few days.
Sulfa Allergy
There is no highly effective alternative. Nitazoxanide 500 mg BID for 7 days or ciprofloxacin 500 mg BID for 7 days, both less reliable with higher failure and relapse rates. Verify the allergy before accepting it, and consider desensitization in severe or protracted disease, since the alternatives genuinely underperform.
Immunocompromised
Severe and protracted disease, with possible biliary involvement.Higher dose, longer course, plus suppressive TMP-SMX 3 times weekly until immune recovery, because without immune reconstitution the infection recurs whenever treatment stops.
Reportable
Nationally notifiable.Report to public health to enable traceback and recalls: a single case is rarely isolated, and the reporting is what identifies the produce lot and prevents the next several thousand cases.
Prevention
Washing does not fully remove oocysts, because they adhere tightly to produce surfaces, so rinsing salad is not protective. Avoid implicated produce during outbreaks. Cooking kills it. There is no vaccine and no chemoprophylaxis.
RoundsRx Infographic Series · #186 · Sepsis & Infection · PDF 141 KB
Text version
Cyclosporiasis One-Pager
2026 alert: US cyclosporiasis surge (CDC HAN). Shredded iceberg lettuce (Taylor Farms de Mexico) served at Taco Bell in IN, KY, MI, OH, WV; central-Mexico iceberg lettuce recalled July 17, 2026. Suspect in any prolonged or relapsing watery diarrhea with a fresh-produce exposure.
Diagnose, do NOT trust a routine O&P:
Watery, non-bloody, prolonged (more than 1 week) or relapsing diarrhea + fatigue, anorexia, weight loss
Incubation median ~7 days; fresh-produce/water or outbreak/travel exposure
Order Cyclospora-specific testing: molecular GI PCR panel (preferred), modified acid-fast stain, or UV autofluorescence
Oocysts 8 to 10 μm, variably acid-fast, autofluoresce blue-green
Intermittent shedding, collect 2 to 3 specimens on different days; one negative does not exclude
Eosinophilia is NOT expected, a normal count does not argue against it
Treatment:
TMP-SMX DS (160/800 mg) 1 tab PO BID × 7 to 10 days, immunocompetent adults/children over 2 months (only reliably effective agent; prevents relapse)
Rehydrate (oral, or IV if volume-depleted); replace electrolytes
Sulfa allergy: nitazoxanide 500 mg BID × 7d OR ciprofloxacin 500 mg BID × 7d, both less reliable, no highly effective substitute
Avoid: ruling it out on a negative routine O&P; expecting azithromycin or standard fluoroquinolone empiric therapy to cover it; stopping therapy early in the immunocompromised (relapse); relying on washing to make contaminated produce safe.
Sources: CDC Cyclosporiasis clinical guidance and Health Alert Network notice (HAN00531, 2026); CDC Cyclosporiasis Outbreak Investigation (July 2026); ADA/IDSA-aligned references and Merck Manual Professional for clinical/diagnostic detail.
Related Topics
C. difficileHIV & ARTSepsis & Septic ShockHantavirus (HPS & HFRS)
Rotation
Infectious Disease
Antibiotic stewardship, sepsis, resistant organisms, and opportunistic infections.
Infection of bone -most commonly S. aureus. Hematogenous in children, contiguous spread in adults (diabetic foot, decubitus ulcers, post-surgical). MRI is the imaging gold standard. Bone biopsy is the diagnostic gold standard. Treatment is 6 weeks of targeted antibiotics -oral step-down is non-inferior to IV (OVIVA 2019).
🔍 Overview
Classification
Type
Mechanism
Typical Patient
Common Organisms
Hematogenous
Bacteremia seeds bone (metaphysis in children, vertebral body in adults)
Children, IVDU (vertebral), sickle cell disease
S. aureus (#1 overall). Salmonella in SCD. Pseudomonas in IVDU.
Contiguous spread
Direct extension from adjacent soft tissue infection, open fracture, or surgery
Chronic ischemia + minor trauma/ulceration → infection spreads to bone
Diabetic foot, peripheral arterial disease
Polymicrobial: S. aureus, Streptococcus, Enterococcus, gram-negatives (E. coli, Proteus), anaerobes (Bacteroides).
Acute vs Chronic
Feature
Acute
Chronic
Duration
< 2 weeks of symptoms
> 6 weeks, or recurrent
Pathology
Suppurative infection, edema
Sequestrum (dead bone), involucrum (new bone around dead bone), sinus tracts
Treatment
Antibiotics often curative alone
Usually requires surgical debridement + prolonged antibiotics
Probe-to-bone test: In diabetic foot ulcers, if a sterile metal probe reaches bone through the ulcer, the positive predictive value for osteomyelitis is ~89%. Simple, bedside, no imaging needed.
🚨 Management
Antibiotic Duration
Standard: 6 weeks of targeted antibiotics. Oral step-down after initial IV is acceptable -OVIVA trial showed oral antibiotics were non-inferior to IV for bone and joint infections at 1 year OVIVA, 2019.
Spinal epidural abscess with neurological compromise -neurosurgical emergency
Diabetic foot with non-healing ulcer and extensive bony involvement -may need amputation
Do NOT start antibiotics before bone biopsy/cultures if the patient is stable. Pre-biopsy antibiotics reduce culture yield and may lead to months of unnecessarily broad therapy. Exception: septic or hemodynamically unstable patients -treat empirically, culture what you can.
🧪 Workup
Diagnostic Evaluation
ESR and CRP -elevated in >90% of cases. ESR >70 is highly suggestive. Use to monitor treatment response.
Blood cultures (×2 sets) -positive in ~50% of hematogenous osteomyelitis. Always obtain before antibiotics.
CBC -WBC may be normal in chronic osteomyelitis. Left shift suggests acute infection.
Plain radiographs -first-line imaging. Changes take 10–14 days to appear (periosteal reaction, lytic lesions). Normal X-ray does NOT rule out early osteomyelitis.
MRI with gadolinium -imaging gold standard. Sensitivity 90–100%, specificity 80–90%. Shows bone marrow edema, soft tissue extent, abscess.
Bone biopsy with culture -diagnostic gold standard. Identifies organism and sensitivities. Essential for targeted therapy. IR-guided or open surgical.
Probe-to-bone test -bedside test for diabetic foot ulcers. PPV ~89% if positive.
MRI cannot distinguish osteomyelitis from Charcot arthropathy in diabetic feet -both show bone marrow edema. Clinical correlation and biopsy are essential in this setting.
💊 Medications
Targeted Therapy (Based on Culture)
Organism
First-Line
Alternative
Duration / Notes
MSSA* *= Methicillin-Sensitive Staph aureus
Nafcillin (Nallpen) 2g IV q4h or Cefazolin (Ancef) 2g IV q8h
Oral step-down: Cephalexin (Keflex) 1g PO QID or Dicloxacillin (Dynapen) 500mg PO QID
6 weeks. IV × 1–2 weeks then oral step-down per OVIVA. Cefazolin preferred for ease of outpatient dosing (q8h vs q4h).
MRSA* *= Methicillin-Resistant Staph aureus
Vancomycin (Vancocin) 15–20 mg/kg IV q8–12h (target AUC/MIC 400–600)
Oral step-down: TMP-SMX (Bactrim) DS 1–2 tabs PO BID + Rifampin (Rifadin) 300mg PO BID
6 weeks. Rifampin for biofilm penetration (hardware infections). Never use rifampin monotherapy -resistance develops rapidly.
Streptococcus
Ceftriaxone (Rocephin) 2g IV daily
Penicillin G or Amoxicillin (Amoxil) 1g PO TID
6 weeks. Strep are reliably penicillin-sensitive.
Pseudomonas
Cefepime (Maxipime) 2g IV q8h or Piperacillin-tazobactam (Zosyn)
Ciprofloxacin (Cipro) 750mg PO BID (oral option with good bone penetration)
6 weeks. Cipro has excellent oral bioavailability and bone penetration -preferred oral agent for Pseudomonas osteo.
Salmonella (SCD)
Ceftriaxone (Rocephin) 2g IV daily
Ciprofloxacin (Cipro) 500mg PO BID
6 weeks. Most common cause of osteomyelitis in sickle cell disease.
6 weeks. Surgical debridement is almost always needed. Vascular assessment essential.
📋 On Rounds
Pimp Questions
What is the most common organism causing osteomyelitis overall? In sickle cell disease?
Overall: S. aureus -accounts for ~60% of all osteomyelitis. In sickle cell disease: Salmonella -infarcted bone from vaso-occlusive crises is a perfect growth medium. This is a classic boards distinction. However, S. aureus is still #1 for septic arthritis in SCD.
Why is bone biopsy considered the gold standard over blood cultures?
Blood cultures are positive in only ~50% of hematogenous osteomyelitis and even less in contiguous spread. Bone biopsy with culture identifies the exact organism and sensitivities, allowing targeted narrow-spectrum therapy for a 6-week course. Without culture data, you may commit a patient to 6 weeks of unnecessarily broad-spectrum antibiotics with more side effects, higher cost, and greater resistance risk.
Can you treat osteomyelitis with oral antibiotics?
Yes. The OVIVA trial (2019) randomized 1,054 patients with bone/joint infections to IV vs oral antibiotics after initial surgical management. Oral was non-inferior at 1 year (treatment failure 14.6% oral vs 14.1% IV). Key caveat: patients had a defined organism with known oral sensitivities, and oral agents with good bone penetration were used (fluoroquinolones, rifampin combinations, linezolid).
Why should you never use rifampin as monotherapy?
Rifampin has excellent biofilm penetration (critical for hardware-associated infections) and good bone penetration. However, resistance develops extremely rapidly with monotherapy -single-step mutations in the rpoB gene occur at a rate of ~10⁻⁸, which is high enough to select resistant mutants within days. Always combine with another active agent (e.g., TMP-SMX, fluoroquinolone, vancomycin).
Clinical Examples
📋 Case 1, Vertebral Osteomyelitis from Bacteremia
Patient: 62M IVDU with 3 weeks of progressive back pain and low-grade fevers. MRI spine: L3-L4 vertebral body edema, disc enhancement, paravertebral phlegmon. Blood cultures: MSSA. No epidural abscess.
Key findings: Vertebral osteomyelitis (most common location for hematogenous osteomyelitis in adults). IVDU + S. aureus bacteremia. Must rule out epidural abscess (MRI with contrast is the gold standard). No surgical indication without abscess or instability.
Management:
Nafcillin 2g IV q4h × 6 weeks (MSSA → beta-lactam preferred over vancomycin for efficacy)
Add rifampin 300 mg PO BID after 2 weeks of IV therapy (enhances biofilm penetration, always in combination, never alone)
TTE → if positive or high suspicion: TEE to rule out endocarditis (IVDU + S. aureus = 30% concurrent IE)
PICC line for outpatient IV antibiotics (OPAT) if clinically stable after initial improvement
Teaching point: Every case of vertebral osteomyelitis needs an MRI of the ENTIRE spine (multifocal in 10-15%) and evaluation for endocarditis (especially S. aureus). Blood cultures are positive in 50-60%, get them before antibiotics.
📋 Case 2, Diabetic Foot Osteomyelitis
Patient: 68M with T2DM (A1c 10.2), presents with non-healing plantar ulcer × 3 months over 2nd metatarsal head. Ulcer depth: bone is palpable with sterile probe ("probe to bone" positive). XR: periosteal reaction and cortical erosion of 2nd metatarsal.
Key findings: Diabetic foot osteomyelitis, "probe to bone" test has 89% PPV for osteomyelitis when positive in a diabetic foot ulcer. X-ray changes confirm chronic osteomyelitis (periosteal reaction, cortical destruction).
Management:
MRI foot (best imaging) to delineate extent of bone involvement and surgical planning
Bone biopsy + culture before antibiotics if possible (wound swabs are unreliable, contaminated with skin flora)
Empiric: vancomycin + piperacillin-tazobactam (cover MRSA + GNR + anaerobes) → narrow based on bone culture
Surgical debridement or limited amputation (ray amputation) for devitalized bone, antibiotics alone cannot cure dead bone
Offloading: total contact cast or removable walking boot (pressure relief is essential for healing)
Teaching point: Wound swab cultures do NOT reflect bone pathogens, bone biopsy is the gold standard for guiding antibiotic therapy. If bone is visible or palpable in a diabetic foot ulcer, treat as osteomyelitis. MRI is the best imaging modality (sensitivity 90%, specificity 80%).
Key findings: Chronic prosthetic joint infection (PJI), onset > 3 months post-op. CoNS is #1 organism in chronic PJI (biofilm former on prosthetic material). Synovial WBC > 3,000 with > 80% PMNs meets MSIS criteria for PJI in a prosthetic joint.
Management:
Two-stage exchange arthroplasty (gold standard for chronic PJI): remove prosthesis → antibiotic spacer × 6-8 weeks → reimplant new prosthesis
IV vancomycin × 6 weeks (CoNS, often methicillin-resistant) + rifampin 300 mg PO BID (biofilm penetration)
Alternative (select cases): DAIR (debridement, antibiotics, implant retention) if: < 3 weeks of symptoms, stable implant, susceptible organism
ID consult for antibiotic optimization and duration
Withhold reimplantation until CRP normalizes and repeat aspiration is negative
Teaching point: Rifampin is the key drug in prosthetic joint infections, it penetrates biofilms that other antibiotics cannot reach. But NEVER use rifampin alone (rapid resistance in days). Always combine with vancomycin, TMP-SMX, or a fluoroquinolone.
📣 Sample Presentation
One-Liner
"Mrs. Garcia is a 62-year-old woman with poorly controlled diabetes (A1c 9.8%) and a non-healing right plantar ulcer × 3 months, now with exposed bone on probing and MRI showing marrow edema in the 2nd metatarsal head consistent with osteomyelitis."
Key Points to Cover on Rounds
Diabetic foot ulcer with positive probe-to-bone. MRI confirms osteomyelitis of 2nd metatarsal head -no abscess, no soft tissue collection. ESR 88, CRP 6.4. Blood cultures × 2 pending. IR-guided bone biopsy scheduled tomorrow -holding antibiotics until culture obtained (patient is hemodynamically stable). Vascular surgery consulted for ABI assessment -pedal pulses palpable. Podiatry involved for wound care. Plan: bone biopsy → targeted antibiotics × 6 weeks, oral step-down when organism and sensitivities known. Glucose management with insulin drip per endocrine.
Monitoring Parameters
ESR and CRP -check weekly. CRP normalizes faster (1–2 weeks). ESR may take weeks to decline. Failure to trend down suggests treatment failure or undrained collection.
CBC with differential -weekly. Monitor WBC normalization.
Vancomycin levels -if on vancomycin, target AUC/MIC 400–600. Check trough before 4th dose, then 1–2× weekly.
Renal function (BMP) -weekly if on vancomycin or aminoglycosides. Watch for nephrotoxicity.
LFTs -if on rifampin (hepatotoxic). Baseline then q2 weeks.
PICC line site -daily inspection for infection, thrombosis if on prolonged IV therapy.
Repeat imaging -not routine. Repeat MRI only if clinical concern for treatment failure or new collection. Imaging lags behind clinical improvement.
RoundsRx Licensed Content - Unauthorized Use Prohibited⚡ Summary
Get Tissue Before Antibiotics
Bone biopsy with culture is the diagnostic gold standard and directs 6 weeks of therapy.Superficial swabs grow colonizers and misdirect treatment.Hold antibiotics for the biopsy in a stable patient; treat empirically first only in sepsis or rapidly progressive infection.
Know the Two Routes of Infection
Hematogenous in children, typically long bone metaphysis, usually monomicrobial.Contiguous spread in adults, from diabetic foot ulcers, decubitus ulcers, post-surgical wounds and trauma, usually polymicrobial. S. aureus is the commonest organism in both. Vertebral osteomyelitis is the classic hematogenous form in adults and often follows bacteremia.
Use the Probe-to-Bone Test in Diabetic Feet
A sterile probe reaching bone through the ulcer has a positive predictive value of about 89%. Free, immediate, and better than most first-line imaging.
MRI Is the Imaging Gold Standard
It shows marrow edema early, defines the extent, and identifies abscess and epidural extension.Plain films are normal for the first 10 to 14 days, because 30 to 50% of bone mineral must be lost before a change is visible, so a normal x-ray early excludes nothing.
Six Weeks, With One Important Exception
Six weeks of targeted therapy is standard when infected bone remains.If all infected bone is resected, only 2 to 5 days of soft tissue coverage is needed, because the infected tissue is gone. Getting that distinction right saves weeks of unnecessary IV therapy after an amputation or complete debridement.
Oral Step-Down Is Non-Inferior
OVIVA showed oral therapy was non-inferior to IV for bone and joint infection when a well-absorbed agent with good bone penetration is available and the organism is susceptible. This avoids a PICC line and its infection and thrombosis risk, and it should be actively considered rather than defaulting to 6 weeks of IV.
Surgery Is Needed More Often Than People Expect
Debride for necrotic bone or sequestrum, drain abscesses, remove infected hardware, and stabilize instability.Chronic osteomyelitis with dead bone will not be cured by antibiotics alone, because there is no blood supply to carry the drug. Retained hardware usually needs removal or long-term suppression.
Follow Response and Look for the Source
Track CRP and the clinical picture rather than repeating MRI early, since imaging changes lag improvement by months and a persistent abnormality is not treatment failure. In vertebral osteomyelitis, get blood cultures and an echocardiogram, since it frequently arises from endocarditis, and watch for epidural abscess, where new neurologic symptoms mean emergent imaging and decompression.
Delirium affects 20–30% of hospitalized patients and up to 80% in ICU. It's a syndrome, not a diagnosis -always find the cause. The hallmark: acute change in attention that fluctuates. Prevention is better than treatment -benzos make it worse.
🔍 Overview
Delirium vs Dementia
Feature
Delirium
Dementia
Onset
Acute (hours–days)
Chronic (months–years)
Course
Fluctuating (waxes and wanes)
Progressive, stable day-to-day
Attention
Impaired (cardinal feature)
Preserved until late stages
Consciousness
Altered (hyperalert or obtunded)
Clear until late stages
Reversibility
Reversible (treat the cause)
Irreversible (but delirium can be superimposed on dementia)
Screening -CAM (Confusion Assessment Method)
Requires feature 1 AND 2 PLUS either 3 OR 4:
1. Acute onset with fluctuating course (was fine yesterday, confused today, better this afternoon, worse tonight)
2. Inattention (can't recite months backward, can't spell WORLD backward, easily distracted) -most important feature
3. Disorganized thinking (incoherent speech, illogical flow of ideas)
4. Altered level of consciousness (anything other than alert -lethargic, stuporous, hyperalert, agitated)
CAM-ICU is the version for intubated/non-verbal patients -uses RASS for consciousness level and a visual attention task (squeeze my hand when you see the letter A).
No evidence it shortens delirium duration. Use lowest effective dose, shortest duration. Monitor QTc (hold if QTc > 500). Avoid in Parkinson's (worsens motor symptoms).
Quetiapine (Seroquel)
25–50 mg PO at bedtime
Sundowning, nocturnal agitation, ICU delirium
Lower EPS risk than haloperidol. Sedating. Preferred in Parkinson's and Lewy body dementia (less D2 blockade). Start 12.5–25 mg in elderly.
Dexmedetomidine
0.2–1.5 mcg/kg/hr IV
ICU delirium (intubated patients)
MENDS, 2007: dex reduced delirium duration vs midazolam in ICU. SEDCOM, 2009: less delirium (54% vs 76.6%) and shorter extubation time vs midazolam. DahLIA, 2016: dex resolved agitated delirium faster and reduced ventilator time. No respiratory depression. Preferred ICU sedative for delirium.
BRAIN-ICU, 2013: ICU delirium duration is independently associated with worse long-term cognitive outcomes at 3 and 12 months -underscoring the importance of aggressive delirium prevention and treatment.
Benzodiazepines WORSEN delirium in almost all cases. Diphenhydramine (Benadryl) is NOT a sleep aid, it's an anticholinergic that causes and worsens delirium. Remove it from every patient's med list.
Delirium in the Elderly: Medication Nuances
Elderly patients are the highest-risk population for both delirium and for harm from the drugs we use to treat it. Non-pharmacologic first (HELP, reorientation, sleep, mobility, sensory aids, remove tethers, med reconciliation). Drugs are a last resort for severe agitation that threatens patient or staff safety. The points below address the two questions that get pimped most: when are benzos ever acceptable in an elderly delirious patient, and what is the right antipsychotic and dose.
When Benzodiazepines ARE Indicated in Elderly Delirium
General rule: benzos worsen delirium and are contraindicated in the elderly for routine agitation. The exceptions, ordered by frequency on wards:
Exception
Agent / Dose
Why Benzos Are Correct Here
Alcohol withdrawal delirium (DTs) Most common benzo indication in elderly delirium
Lorazepam 1–2 mg IV q1–2h symptom-triggered (CIWA), or diazepam 5–10 mg IV loading. Prefer lorazepam in liver disease.
Benzos replace the GABA tone that alcohol was providing. Underdosing kills (seizures, aspiration). Haloperidol lowers seizure threshold and does NOT treat withdrawal.
Benzodiazepine withdrawal
Restart a long-acting benzo (diazepam or chlordiazepoxide) at equipotent dose, then taper by 10–25% every 1–2 weeks.
Abrupt discontinuation of chronic benzos causes a withdrawal delirium that mirrors DTs. Requires slow taper, not abstinence.
Lorazepam 1–2 mg IV/IM challenge (both diagnostic and therapeutic). If response, continue 1–2 mg q4–6h scheduled.
Catatonia responds rapidly to lorazepam. Antipsychotics can worsen or trigger malignant catatonia, so get the diagnosis right first. Always consider catatonia in a quiet, unresponsive elderly patient.
Seizure or non-convulsive status epilepticus (NCSE)
Lorazepam 2–4 mg IV, then load anti-seizure med (levetiracetam, fosphenytoin).
Persistent post-ictal confusion or fluctuating delirium with no clear cause should trigger EEG. Benzos stop the seizure, ASM prevents recurrence.
Neuroleptic malignant syndrome (NMS) or serotonin syndrome
Lorazepam 1–2 mg IV q4–6h as adjunct to supportive care.
Benzos reduce rigidity and agitation. Primary treatment is stopping the offending agent and cooling; benzos buy time and reduce muscle breakdown.
Not an exception: "He was agitated so I gave him Ativan." Routine agitation in an elderly delirious patient is NOT an indication for a benzo. It prolongs delirium, increases fall risk, and worsens aspiration. Use a low-dose antipsychotic instead, and run the mimic sweep first, see the Acute Agitation tab for the bedside playbook.
Antipsychotic Selection in Elderly Delirium
Start with the lowest effective dose, use for the shortest duration, and stop as soon as agitation resolves. Remember MIND-USA, 2018: antipsychotics do not shorten delirium duration or improve mortality, they only manage dangerous agitation.
Agent
Elderly Dose
When to Choose
Cautions
Haloperidol (Haldol) FIRST LINE
0.25–0.5 mg PO/IV/IM q4–6h PRN. Max ~3 mg/24h in frail elderly.
Check QTc before dosing, hold if > 500. EPS, akathisia. Contraindicated in Parkinson's and Lewy body dementia (precipitates motor crisis).
Quetiapine (Seroquel) DLB / PARKINSON'S
12.5–25 mg PO at bedtime, can give 12.5 mg q12h PRN. Start low, titrate slowly.
Parkinson's disease, Lewy body dementia, sundowning, nocturnal agitation. Less D2 blockade so fewer motor side effects.
Sedating (can cause daytime somnolence). Orthostatic hypotension in elderly. Still carries the FDA black box warning.
Risperidone (Risperdal)
0.25–0.5 mg PO BID PRN.
Alternative to haloperidol when oral route available.
EPS at higher doses. Orthostatic hypotension. Not preferred in Parkinson's / DLB.
Olanzapine (Zyprexa)
2.5–5 mg PO or IM q8–12h PRN.
Refractory agitation, when oral route fails and IM needed.
Sedation, weight gain, anticholinergic effects at higher doses, orthostatic hypotension.
Dexmedetomidine ICU ONLY
0.2–1.5 mcg/kg/hr IV infusion.
ICU delirium, especially ventilated patients or when extubation is imminent. MENDS, 2007, SEDCOM, 2009, DahLIA, 2016.
Requires continuous monitoring. Bradycardia, hypotension. Not for floor patients.
FDA black box warning:all antipsychotics (typical and atypical) carry a boxed warning for increased all-cause mortality in elderly patients with dementia-related psychosis, driven mostly by cerebrovascular events and pneumonia. Use the lowest effective dose, shortest duration, document indication and discussion of risks, and stop as soon as acute agitation resolves. Do NOT continue on discharge without a clear plan to taper.
Also avoid in elderly delirium: diphenhydramine (anticholinergic, not a sleep aid), hydroxyzine (anticholinergic), meperidine (active metabolite causes delirium and seizures), metoclopramide (can worsen agitation and cause EPS), cyclobenzaprine, oxybutynin, and promethazine. All are on the Beers List and are among the top offenders for hospital-acquired delirium.
⚠️ Acute Agitation on the Wards
Every agitation call is a workup before it's a prescription. The 5-minute bedside sweep below catches the reversible causes that look like delirium but kill faster if missed. Run it BEFORE writing for haloperidol, every time. Hyperactive delirium IS agitation in ~95% of ward cases, so the workup half of this topic still applies. This tab is the "you walked into the room at 3 AM" execution layer.
Step 1, The 5-Minute Mimic Sweep
These are the agitation mimics that get treated wrong if you sedate first. Order reflects "fastest to kill if missed."
Mimic
How to catch it in 60 sec
Why this is the first move
Hypoxia
SpO₂, RR, accessory muscle use
A hypoxic patient sedated with haldol stops fighting AND stops breathing. SpO₂ before any sedative, no exceptions.
Hypoglycemia
Fingerstick
Looks identical to delirium. Missed → seizure, anoxic injury, death. D50 1 amp IV solves it in 90 seconds.
Under-treated pain is the most common reversible trigger of post-op agitation. Antipsychotic without analgesic just snows a hurting patient.
Hypercapnia
COPD/OSA history, recent opioids, somnolence preceding agitation. VBG/ABG if suspected.
CO₂ narcosis presents as agitation BEFORE somnolence. Sedating accelerates the crash to intubation.
Acute intracranial event
Focal exam, recent fall, anticoagulation, asymmetric pupils, new headache
Anticoagulated patient with new agitation = non-contrast head CT before sedation. A sedated stroke patient masks the deficit.
NMS or serotonin syndrome
Rigidity, hyperreflexia (SS) or lead-pipe rigidity (NMS), fever, recent antipsychotic or serotonergic agent
BOTH contraindicate haldol. Stop offender, cool, supportive care; benzodiazepines are correct here, antipsychotics are not. See NMS vs Serotonin Syndrome.
Step 2, Verbal De-Escalation and Non-Pharm
These cost nothing and run in parallel with the mimic sweep. Most ward agitation episodes end here without a milligram of anything.
One staff member talks, others step back. Multiple voices escalate. Get to eye level, hands visible, slow speech. Why: a delirious frontal cortex is overwhelmed by stimulus; reducing inputs is the fastest de-escalation lever.
Reorient briefly, then validate. "Mr. K, you're at the hospital, it's Tuesday morning, your daughter is on her way. I can see you're frustrated." Why: validation before redirection. Telling a delirious patient "calm down" is data they can't process; "I can see you're upset" is.
Glasses on, hearing aids in, dentures in.Why: you cannot de-escalate someone who can't see or hear you. Sensory deprivation manufactures agitation; every encounter without aids generates more confusion.
Lights up, curtains open, TV off, monitor alarms silenced if safe.Why: ambient stimulus drives the hyperactive subtype. Daytime light also re-anchors circadian rhythm, which is a downstream delirium fix.
Untether what you can. Foley out if not needed, telemetry off if not indicated, IV moved to less prominent arm. Why: tethers are the #1 thing patients pull at, AND Foleys cause CAUTI which causes more delirium = vicious loop.
Family at bedside, even at 2 AM. Phone-speaker if family can't come in. Why: a familiar voice often resolves what no drug will. Family also remember the patient's baseline and can tell you what's actually different.
Toileting offer + warm drink + snack.Why: "is there something you need?" fixes a surprising fraction of "agitated" patients. The complaint is often something basic the resident skipped past.
1:1 sitter as soon as available.Why: always preferred over restraints. Restraints INCREASE agitation, injury, pressure ulcers, aspiration risk, and prolong delirium. A sitter de-escalates; a restraint escalates.
Indications, document them in the chart: imminent risk of harm to self or staff, OR pulling lines/tubes essential for medical care, OR refusing essential treatment in a patient lacking capacity due to delirium. NOT for hypoactive delirium, not for sundowning alone, not for sleep, not because the patient is "annoying the nurses."
Goal: calm and arousable, NOT asleep. Snowing the patient just delays the diagnosis and prolongs LOS. Antipsychotics manage behavior; they do NOT shorten delirium duration (HOPE-ICU, 2013, MIND-USA, 2018, AID-ICU, 2022).
First-Line: Haloperidol
Dose: 0.25–0.5 mg PO/IV/IM in older adults (≥ 65 or frail). 1–2 mg in younger non-frail adults. May repeat q30 min PRN. If you're past ~3 mg/24h on the wards, stop and reassess, the diagnosis is wrong or the patient needs a higher level of care.
Onset: IV ~5–10 min, IM ~15–30 min, PO ~30–60 min. Pick the route to match how fast you need control AND how cooperative the patient is.
Why first-line: decades of ward use, IV/IM/PO all available, no active metabolites, minimal hypotension, minimal anticholinergic load.
Pre-dose checks: EKG (QTc < 500), K, Mg. Repeat EKG after cumulative dose ≥ 2 mg or any other QT-prolonger on board. Why: haloperidol prolongs QT and torsades is the dose-related lethal complication.
Avoid in: Parkinson's disease, Lewy body dementia, prior NMS, QTc > 500, alcohol or BZD withdrawal as the primary cause.
When Haloperidol Is Contraindicated
Scenario
Drug
Dose
Why this one
Parkinson's disease or Lewy body dementia
Quetiapine (Seroquel)
12.5–25 mg PO; can repeat q12h
Least D2 blockade of the antipsychotics → least extrapyramidal effect. Haldol can precipitate parkinsonian crisis or NMS in these patients.
QTc 470–500 or other QT concern
Olanzapine (Zyprexa)
2.5–5 mg PO/IM (PO disintegrating available)
IM available when refusing PO, less QT effect than haldol at low doses. Anticholinergic at higher doses, so keep it low in elderly.
Need oral, haldol contraindicated for non-Parkinson's reason
Risperidone (Risperdal)
0.25–0.5 mg PO BID PRN
Solid PO option when IV access is fine and you need a lower-EPS-risk-than-haldol agent. Avoid in Parkinson's and DLB.
When First-Line Is Inadequate, Escalation Options
A first dose of haldol 0.5 mg may not produce control in 30 minutes. Two legitimate moves before switching agents: (1) repeat the dose if EKG and tolerance are fine and cumulative is still < 3 mg/24h; (2) re-run the mimic sweep, you may have missed the trigger. If repeat dosing fails OR causes EPS/akathisia, switch agents. The parenteral options below are listed in approximate order of how often they are reached for on the wards.
Drug
Dose
Onset
When to choose / cautions
Droperidol (Inapsine) FAST IV
2.5 mg IV/IM, may repeat q15-30 min. Cap ~10 mg/24h on the wards. (5 mg in younger non-frail adults; 1.25 mg in the very elderly.)
IV 3-10 min IM 15-30 min
Butyrophenone (same class as haldol) with faster IV onset and more sedation per milligram. Carries an FDA black box (2001) for QT prolongation and torsades based on older 25+ mg surgical-anesthesia and antiemetic doses; at modern 2.5-5 mg agitation doses with baseline EKG screening, recent ED literature (Calver 2015, Perkins 2015) shows safety profile comparable to haldol, and many EDs now use droperidol as the preferred parenteral antipsychotic for severe agitation. Pre-dose checks identical to haldol: EKG (QTc < 500), K, Mg. Same contraindications as haldol (Parkinson's, DLB, prior NMS).
Olanzapine (Zyprexa) IM SEDATION
5-10 mg IM (Zydis ODT also available for cooperative PO refuser). Max 30 mg/24h. Cap at 10 mg single dose in older adults.
15-45 min IM
More sedating than haldol or droperidol, useful when the dominant problem is the patient cannot rest. Do NOT combine with IM/IV lorazepam within 1 hour, FDA black box for cardiorespiratory depression and death (especially in elderly). Anticholinergic load at higher doses, hence the elderly cap.
Ziprasidone (Geodon) IM NON-PARKINSON ATYPICAL
10-20 mg IM, may repeat q4h. Max 40 mg/24h.
15-30 min IM
Useful when haldol is contraindicated for non-QT reasons (Parkinson's, prior NMS) and the patient is refusing PO. Less sedating than olanzapine, less anticholinergic. Caveat: ziprasidone has the highest QT-prolonging effect of the atypical antipsychotics, so it does NOT rescue you when QTc is the contraindication, the alternative for QT-prolonged patients is non-pharmacologic management plus level-of-care escalation.
Level-of-care escalation CALL FOR HELP
Rapid response → anesthesia → step-down or ICU transfer
Immediate
If 2-3 antipsychotics across 60-90 min have failed, stop and call. The diagnosis is probably wrong (re-run the mimic sweep, consider NMS, serotonin syndrome, status epilepticus, ICH, sepsis), or the patient needs continuous dexmedetomidine 0.2-1.5 mcg/kg/hr in a monitored setting, the only reliably escalatory pharmacologic option beyond bolus antipsychotics, and not appropriate for a regular medical floor. DahLIA, 2016: dex resolves agitated delirium faster than placebo in ventilated patients.
Ketamine 4-5 mg/kg IM (or 1-2 mg/kg IV slow) is NOT a ward order. Reserved for life-threatening agitation in monitored settings (ED, ICU, anesthesia present). Onset 3-5 min IM, dissociative. If you are reaching for ketamine on a regular medical floor, you needed to escalate level of care 30 minutes earlier. Cautions: laryngospasm (rare), hypersalivation (premedicate with glycopyrrolate), emergence reactions, BP/HR rise. Useful framing: "ketamine is the answer when the patient will hurt someone in the next 60 seconds, in a place where airway and ICU are seconds away."
The "B-52" cocktail (Haldol 5 mg + Lorazepam 2 mg + Benadryl 50 mg IM) is NOT appropriate on a medical ward for delirium. Diphenhydramine adds anticholinergic load (worsens delirium), lorazepam is harmful in non-withdrawal delirium, and the doses are 4–10× too high for an older inpatient. Patients who genuinely need that level of sedation need an ICU evaluation, not a ward IM cocktail.
Avoid IM olanzapine + IM/IV lorazepam together. FDA black box for cardiorespiratory depression and death, especially in elderly. Separate by ≥ 1 hour if both are genuinely needed.
Step 4, Physical Restraints (Last Resort)
Indication: imminent harm AND less-restrictive options have failed or are unsafe. Document both halves explicitly. Why: a chart that just says "patient agitated, restraints applied" doesn't meet CMS standards and is medico-legally exposed.
Order requirements: physician order, time-limited (CMS: 4 hours adults, 2 hours ages 9–17, 1 hour under 9), specific behaviors documented, less-restrictive alternatives tried documented. Renewal requires face-to-face evaluation.
Monitoring: circulation, skin integrity, range of motion, toileting, hydration q15 min initially. Why: restraint-related injuries (pressure, brachial plexus, asphyxia from prone restraint) are "never events" and the q15 min check is what catches them.
Mitts before 4-points. Mittens prevent line-pulling without immobilizing limbs. 4-point restraint is rarely necessary on a medical ward outside acute psychiatric emergencies.
Remove ASAP. Reassess at every nursing check, not just at order renewal. Why: every additional hour increases delirium duration, pressure injury, and aspiration risk.
Step 5, After the Event
Reassess in 30 minutes for response and side effects: dystonia, akathisia, hypotension, oversedation, EPS. Why: akathisia is commonly mistaken for "still agitated" → wrong response is to give more antipsychotic, which makes it worse.
Repeat EKG if cumulative haloperidol ≥ 2 mg or any other QT-prolonger on board.
Daily reassessment of need. Write a stop date on the antipsychotic order. Why: most ward antipsychotics started for delirium get discharged on the patient, leading to outpatient falls, CV events, and the FDA-warned mortality bump.
Document trigger identified (or "no clear trigger after sweep"), what was tried, what worked, what dose. Why: the next overnight team needs the playbook so they don't restart from zero at 3 AM.
3 AM Decision Tree, "Patient Is Agitated Right Now"
SpO₂, fingerstick, full vitals while you walk in.
Bladder scan if not done in last 6h. Rectal if no BM in 3 days.
CIWA + last-drink history if any tremor, tachycardia, HTN, or diaphoresis.
Pain assessment (verbal scale, or PAINAD if non-verbal).
Sensory aids on, lights up, sitter requested, family called.
If still agitated AND a danger to self or staff: Haldol 0.5 mg IV (or 0.25 mg if frail/very elderly). Re-evaluate in 30 min. Do not redose more frequently than q30 min without re-eval.
If haldol inadequate at 30 min: repeat once if cumulative < 3 mg AND EKG OK, OR switch agents, droperidol 2.5 mg IV (faster onset), olanzapine 5-10 mg IM (more sedation), ziprasidone 10-20 mg IM (when haldol contraindicated for Parkinson's). See escalation table above.
If 2-3 agents across 60-90 min have failed: stop, re-run mimic sweep, reconsider diagnosis (NMS, serotonin syndrome, status epilepticus, ICH, sepsis), and call rapid response, the patient needs ICU/step-down for dexmedetomidine, not more haldol.
If withdrawal: Lorazepam 1–2 mg IV + thiamine 100 mg IV (thiamine BEFORE glucose if EtOH).
Document trigger and response before you leave the room.
High-Yield Why-Pearls
The most dangerous moment in ward agitation is the order for sedation written before the SpO₂ is checked. Hypoxia and hypoglycemia look identical to delirium and they kill faster.
Every Foley pulled is one less reason to be agitated tomorrow. Untether early and often.
A 1:1 sitter is medicine. Restraints are a complication waiting to happen.
Haloperidol calms behavior; it does not treat delirium. The fix is the trigger, not the prescription.
Akathisia from haldol looks like "still agitated." Giving more makes it worse. Always consider EPS before redosing.
If you write for an antipsychotic, write the stop date in the same order. Every. Single. Time.
📋 On Rounds
What is the #1 modifiable risk factor for delirium?
Medications. The most common offenders: (1) Anticholinergics (diphenhydramine, oxybutynin, promethazine, cyclobenzaprine -check the Beers List), (2) Benzodiazepines (lorazepam, midazolam -strongly associated with delirium in ICU and elderly), (3) Opioids (especially meperidine -active metabolite normeperidine causes seizures and delirium), (4) Steroids (high-dose), (5) Polypharmacy (≥ 5 medications increases delirium risk independently).
What is the CAM-ICU and how does it differ from the regular CAM?
CAM-ICU is a validated delirium screening tool adapted for patients who cannot speak (intubated, nonverbal). It tests: (1) acute onset/fluctuation, (2) inattention (squeeze hand on letter 'A' in S-A-V-E-A-H-A-A-R-T -errors ≥ 2 = positive), (3) altered level of consciousness (RASS ≠ 0), (4) disorganized thinking (simple questions + commands). Delirium = features 1+2 plus either 3 or 4.
What is the HELP protocol and why does it work better than medications for delirium?
HELP (Hospital Elder Life Program) is a multicomponent non-pharmacologic intervention that reduces delirium incidence by 33-40%. Components: (1) Orientation: clocks, calendars, whiteboards with date/team names, familiar objects from home. (2) Sleep: lights off at night, minimize overnight vitals/labs/interruptions, warm milk/herbal tea, earplugs + eye masks
What is the role of antipsychotics in delirium?
Antipsychotics do NOT prevent or treat delirium -this was shown definitively by MIND, 2018 (haloperidol and ziprasidone vs placebo in ICU delirium) and AID-ICU, 2022 (haloperidol didn't reduce delirium days or mortality). Their only role: severe agitation that threatens patient or staff safety when non-pharmacologic measures have failed and the patient is pulling lines or at risk of self-harm.
Patient agitated overnight. What do you check before writing for haloperidol?
Run the 5-minute mimic sweep first. SpO₂ (hypoxia), fingerstick (hypoglycemia), tremor/HR/last-drink (alcohol or BZD withdrawal), bladder scan (retention), rectal/last-BM (impaction), pain assessment (under-treated pain). Also: hypercapnia in COPD/OSA, focal neuro signs in anticoagulated patients (head CT), rigidity + recent antipsychotic or serotonergic agent (NMS/SS). Sedating any of these without identifying them can kill, hypoxia and hypoglycemia look identical to delirium and crash faster.
Why is the "B-52" cocktail (Haldol 5 + Ativan 2 + Benadryl 50 IM) inappropriate on a medical ward?
Three reasons. (1) Diphenhydramine is anticholinergic and worsens delirium, the opposite of what you want. (2) Lorazepam is contraindicated in non-withdrawal delirium, it prolongs the episode via GABAergic disinhibition. (3) The doses are 4-10x too high for an older inpatient (haldol target is 0.25-0.5 mg, not 5 mg). The B-52 is an ED chemical-restraint cocktail for a young, otherwise healthy, severely agitated psychiatric patient, NOT a prescription for ward delirium. If a ward patient genuinely needs that level of sedation, they need ICU evaluation.
You gave 0.5 mg haldol IV 30 minutes ago. Patient is still restless and now pacing. Do you give more?
Not without ruling out akathisia first. Haldol-induced akathisia (subjective inner restlessness, inability to sit still, pacing) looks like persistent agitation, but giving more antipsychotic makes it worse. Treatment is the opposite: reduce or stop haldol, consider propranolol 10-20 mg PO or benztropine 1-2 mg if severe, switch to a lower-D2 agent like quetiapine if antipsychotic still needed. The akathisia trap is a top reason ward residents end up snowing patients with escalating doses chasing a side effect.
Patient remains agitated after 1 mg haldol IV. EKG, K, and Mg are fine. Akathisia ruled out. What's your next move?
Switch agents, do not just keep redosing haldol past ~3 mg. Three reasonable parenteral options: (1) Droperidol 2.5 mg IV/IM, faster IV onset (3-10 min) and slightly more sedating, same EKG checks as haldol; (2) Olanzapine 5-10 mg IM when more sedation is the goal (do NOT combine with IM/IV lorazepam within 1 hour, FDA black box); (3) Ziprasidone 10-20 mg IM when haldol is contraindicated for Parkinson's or prior NMS (note: ziprasidone has the most QT effect of atypicals, so it does NOT rescue you from a QT contraindication). If 2-3 agents fail across 60-90 min, the diagnosis is wrong or the patient needs ICU/step-down for a dex drip, call rapid response.
What is droperidol, and why does it carry an FDA black box warning?
Droperidol is a butyrophenone antipsychotic, same drug class as haloperidol, with faster IV onset (3-10 min vs 5-10 min) and more sedation per milligram. Mechanism: D2 antagonist with α-adrenergic blockade. The 2001 FDA black box for QT prolongation and torsades was based on case reports at older surgical-anesthesia and antiemetic doses (often > 25 mg, occasionally up to 50-100 mg). Modern agitation dosing is 2.5-5 mg with baseline EKG, K, Mg, and recent ED literature (Calver 2015, Perkins 2015) shows safety comparable to haldol at these doses. The drug was largely pulled from US hospitals after the black box, but has been making a steady comeback in EDs as the preferred parenteral antipsychotic for severe acute agitation. Same contraindications as haldol: Parkinson's disease, Lewy body dementia, prior NMS, QTc > 500.
Clinical Examples
📋 Case 1, Hyperactive Delirium in Post-Surgical Patient
Patient: 78M with mild dementia (baseline MMSE 22), POD 2 from hip fracture repair, found pulling at IV lines, yelling at staff, trying to climb out of bed at 2 AM. Received morphine PCA and diphenhydramine for sleep.
Key findings: HR 108, BP 162/94, Temp 37.2°C. Agitated, disoriented to place and time, unable to spell "WORLD" backwards. CAM positive. UA: positive for UTI. Medications: morphine, diphenhydramine (both high-risk).
Non-pharmacologic measures: reorient frequently, mobilize early, sleep hygiene, glasses/hearing aids at bedside
For acute safety: haloperidol 0.5-1 mg IV/IM once. Check QTc first. Avoid in Parkinson or Lewy body dementia
Teaching point: Always remove offending medications (anticholinergics, benzodiazepines, opioids) before reaching for antipsychotics. The MIND Trial, 2018 showed antipsychotics do NOT treat delirium.
📋 Case 2, Hypoactive Delirium Missed on Rounds
Patient: 82F with CHF and CKD, admitted for pneumonia 4 days ago. Nursing notes: "sleeping most of day, not eating." Intern documents "oriented x3" based on brief interaction.
Key findings: Drowsy, slow to respond. Unable to list months backwards (inattention). Does not know she is in the hospital. CAM positive. RASS -2. Medications: lorazepam 0.5 mg HS, metoclopramide.
Management:
Stop lorazepam (benzodiazepines are a major delirium precipitant in elderly)
Stop metoclopramide (dopamine antagonist, can worsen delirium)
Teaching point: Hypoactive delirium is far more common (70% of cases) but frequently missed because patients are quiet. It carries worse prognosis than hyperactive delirium. Screen every elderly patient daily with CAM.
📋 Case 3, ICU Delirium in Ventilated Patient
Patient: 65M intubated for 4 days with ARDS from pneumonia. Nurse reports intermittent agitation and lethargy. RASS fluctuating between -1 and +2.
Key findings: CAM-ICU positive. Currently on propofol drip and fentanyl for sedation. No spontaneous breathing trial attempted today. Foley catheter and bilateral soft restraints in place.
Management:
Switch from propofol/benzodiazepine sedation to dexmedetomidine (associated with less delirium) SEDCOM, 2009
Implement ABCDEF bundle: A ssess pain · B oth SAT + SBT daily · C hoice of light sedation · D elirium screening BID · E arly mobility · F amily engagement
Target lightest sedation possible (RASS 0 to -1). Daily sedation vacation + spontaneous breathing trial
Remove Foley (independent risk factor for delirium). Remove restraints if safe
Teaching point: The ABCDEF bundle reduces ICU delirium, ventilator days, and mortality. Every day of delirium in the ICU independently increases mortality by 10%. Dexmedetomidine is preferred over benzodiazepines for sedation.
📣 Sample Presentation
One-Liner
"Mrs. Johnson is an 82-year-old with dementia admitted for UTI who is now acutely agitated, pulling at lines, not recognizing family. CAM positive (acute onset, inattention, disorganized thinking). Hyperactive delirium."
Key Points to Cover on Rounds
CAM positive -hyperactive delirium. Precipitant: UTI (on ceftriaxone day 2) + new environment + disrupted sleep. Medication review: Benadryl was ordered PRN sleep -discontinued (anticholinergic). Oxybutynin on home med list -held. Non-pharmacologic interventions: reorientation board, family at bedside, glasses and hearing aids in place, lights on during day/off at night, minimize tethers, PT mobilization. Bladder scan: no retention. Constipation: last BM 3 days ago → PEG 3350 + senna. Avoiding antipsychotics unless severe agitation threatening safety.
🧪 Workup
Workup -Delirium
Delirium is a clinical diagnosis, and the workup exists to find the precipitant, not to confirm the syndrome. Use a validated tool, then hunt the cause. Hypoactive delirium is the commonest form and the most missed, because a quiet patient does not prompt anyone to look.
1. Confirm the diagnosis
CAM on the ward or CAM-ICU in intensive care. Positive requires acute onset with a fluctuating course and inattention, plus either disorganized thinking or an altered level of consciousness.
4AT is a fast alternative needing no training, and it scores arousal, so it catches the hypoactive patient.
Establish the baseline from family or the care home before calling it delirium. Delirium superimposed on dementia is common and is still delirium.
2. Find the precipitant
Review the medication chart first. Anticholinergics, benzodiazepines, opioids, steroids, and any drug started in the last 72 hours. This is the highest-yield single step and the most modifiable.
Infection: urinalysis and culture, chest radiograph, and a careful skin and line examination. Do not treat asymptomatic bacteriuria as the cause; it is a common false trail.
Metabolic: CBC, electrolytes with calcium and magnesium, glucose, renal and liver function, TSH, and B12 where the picture fits.
Hypoxia and hypercapnia: pulse oximetry and an arterial or venous blood gas if respiratory disease is plausible.
Retention and constipation: a bladder scan and an abdominal examination. Both are common, easily missed, and immediately reversible.
Withdrawal: alcohol and benzodiazepines. Take a substance history from family if the patient cannot give one.
Imaging is not routine. Reserve CT head for a focal neurological deficit, a fall or head injury, anticoagulation, a depressed level of consciousness, or delirium with no identified cause after a full assessment. Scanning every confused patient delays the real diagnosis. Consider EEG only when non-convulsive status epilepticus is a genuine possibility, such as unexplained fluctuating consciousness after a witnessed seizure.
💊 Medications
Medications -Delirium
Non-pharmacologic interventions FIRST. Medications are second-line, reserved for severe agitation endangering patient or staff safety. No medication treats delirium -only addresses symptoms while you fix the cause.
Non-Pharmacologic (First-Line)
Reorientation: clock, calendar, familiar objects, consistent caregivers, windows for day/night cycle
Sleep hygiene: minimize nighttime vitals/interruptions, reduce noise, lights off at night, cluster care
Mobility: early ambulation, PT/OT, avoid bed rest. Remove tethers (telemetry, Foley, restraints) when possible
Low-dose antipsychotic for acute agitation. Avoid if QTc >500 ms. Check ECG before and after. Not FDA-approved for delirium but widely used.
Quetiapine (Seroquel)
12.5-50 mg PO BID-TID
PO
More sedating, useful for nighttime agitation. Lower EPS risk than haloperidol. Monitor QTc.
Dexmedetomidine (Precedex)
0.2-1.5 mcg/kg/hr IV
IV
Alpha-2 agonist. ICU setting for intubated patients. Maintains arousability. Reduces delirium duration vs benzodiazepines. Risk: bradycardia, hypotension.
Benzodiazepines AVOID
-
-
WORSEN delirium in most cases. Exception: alcohol withdrawal delirium and benzodiazepine withdrawal -benzodiazepines are treatment of choice for these specific etiologies.
⚡ Summary
Summary
It Is a Syndrome, Not a Diagnosis
Always find the cause.The hallmark is an acute change in attention that fluctuates, with disorganized thinking and an altered level of consciousness. It affects 20 to 30% of hospitalized patients and up to 80% in the ICU, and it independently predicts death, institutionalization and long-term cognitive decline.
Screen With CAM
Acute onset and fluctuating course, plus inattention, plus either disorganized thinking or an altered level of consciousness.Inattention is the cardinal feature: test it directly with digit span or months backward rather than assuming an oriented patient is not delirious.
Hypoactive Delirium Is the One That Gets Missed
The quiet, withdrawn, drowsy patient is far more common than the agitated one and carries a worse prognosis, precisely because nobody calls about them. Screen systematically rather than waiting to be told a patient is confused.
Work the Cause With AEIOU TIPS
Alcohol and drugs, Electrolytes and endocrine, Insulin (glucose), Oxygen and opiates, Uremia; Trauma, Infection, Psychiatric and poisons, Stroke and seizure. Check a glucose immediately, review every medication, and look for retention, constipation and pain, which are common, treatable and routinely missed.
Non-Pharmacologic Measures Come First
Reorientation, glasses and hearing aids in place, mobilization, sleep hygiene without sedatives, family presence, hydration and removing tethers, catheters, lines and telemetry. The HELP bundle reduces delirium incidence by 30 to 40% and outperforms any drug.
Benzodiazepines Make It Worse
They cause and prolong delirium in almost every setting.The exceptions are alcohol and benzodiazepine withdrawal, and neuroleptic malignant syndrome, where they are the treatment. Outside those, reaching for lorazepam for an agitated confused elderly patient deepens and lengthens the episode.
Use Antipsychotics Narrowly
Only for agitation that threatens the patient's or staff's safety, or that prevents essential care.Haloperidol first line at low dose, with ECG monitoring for QT.Avoid it in Parkinson disease and Lewy body dementia, where quetiapine is preferred. Antipsychotics do not prevent delirium, do not shorten it and carry a mortality warning in dementia, so they treat a symptom, not the syndrome.
Restraints Last, and Plan the Follow-Through
Physical restraints increase injury, agitation and delirium duration and are a last resort with frequent reassessment. Delirium can take weeks to months to resolve, so tell the family it is expected to persist beyond discharge, arrange cognitive follow-up, and stop the antipsychotic before discharge rather than letting it become an inadvertent long-term prescription.
RoundsRx Infographic Series · #89 · Neurology · PDF 148 KB
Text version
Delirium & Altered Mental Status -Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card. All tabs will print on the same page for a complete topic summary.
DELIRIUM & ALTERED MENTAL STATUS -AT A GLANCE
📋 Diagnose: CAM positive (acute + fluctuating + inattention + either disorganized thinking or altered LOC) → see Overview tab 🧪 Workup: AEIOU TIPS, focused labs + imaging → see Workup tab ⚡ Treat: Non-pharm first (HELP protocol), find and fix the trigger → see Management tab ⚠️ Acute agitation: 5-min mimic sweep (SpO₂, glucose, withdrawal, retention, pain) BEFORE any sedative; verbal de-escalation + 1:1 sitter; haldol 0.25–0.5 mg only if safety threatened → see Acute Agitation tab 💊 Drugs: Haldol first-line, quetiapine for Parkinson's or DLB, NO benzos except for withdrawal, seizure, catatonia, NMS, or SS → see Medications tab 📣 Present: One-liner + key points → see Rounds tab
Related Topics
Guillain-Barré SyndromeHeadache & MigraineHeat StrokeIntracerebral HemorrhageMyasthenic CrisisNMS vs Serotonin Syndrome
EMERGENTNeurology
Guillain-Barré Syndrome
Acute inflammatory demyelinating polyneuropathy -ascending weakness 1–4 weeks after infection. 30% need intubation. The key danger: respiratory failure from diaphragm weakness. Monitor NIF and FVC serially. Do NOT wait for ABG to deteriorate -intubate early.
🔍 Overview
Clinical Features
Ascending symmetric weakness -starts in legs, progresses to arms, trunk, respiratory muscles, cranial nerves
Areflexia or hyporeflexia -characteristic finding
Preceded by infection 1–4 weeks prior in ~70%: Campylobacter jejuni (#1), CMV, EBV, HIV, Mycoplasma, Zika
Albuminocytologic dissociation: elevated protein (> 45 mg/dL) with normal WBC (< 10). May be normal in first week. If WBC > 50 → think HIV, Lyme, sarcoidosis, or lymphomatous meningitis.
Nerve conduction studies / EMG
Demyelination pattern: prolonged distal latencies, conduction block, slowed conduction velocity, absent F waves. May be normal first few days. Repeat at 2 weeks if initially normal.
Anti-ganglioside antibodies
Anti-GM1 (AMAN variant), anti-GQ1b (Miller Fisher -ophthalmoplegia + ataxia + areflexia). Not required for diagnosis.
Respiratory Monitoring -The 20/30/40 Rule
Intubate if ANY of: FVC < 20 mL/kg, NIF < −30 cmH₂O, or FVC decline > 30% from baseline. Do NOT wait for hypercapnia or hypoxia on ABG -by then it's too late. Check FVC and NIF q4–6h in all GBS patients.
The Erasmus GBS Respiratory Insufficiency Score (EGRIS) predicts need for ventilation: rapid progression, high disability score at admission, and facial/bulbar weakness are the strongest predictors.
🚨 Management
Immunotherapy
Treatment
Dose
Notes
IVIG 1ST LINE
0.4 g/kg/day IV × 5 days
Equivalent efficacy to plasmapheresis. Easier to administer. Side effects: headache, renal failure (check IgA first -IgA-deficient patients get anaphylaxis), aseptic meningitis, thromboembolic events. GBS IVIG Trial, 1992
Plasmapheresis (PLEX) EQUIVALENT
5 exchanges over 2 weeks
Equivalent to IVIG. Preferred if IVIG contraindicated. Requires large-bore central access. More hemodynamic effects. Guillain-Barré Syndrome Study Group, 1985
Do NOT give both IVIG and PLEX -PLEX removes the IVIG you just gave. Pick one. Do NOT give corticosteroids -no benefit in GBS (unlike in CIDP or myasthenia).
Supportive Care
ICU admission for all moderate-severe GBS (rapid progression, bulbar involvement, autonomic dysfunction)
FVC + NIF q4–6h -trend is more important than single values
DVT prophylaxis -immobile patient, high VTE risk. Enoxaparin + SCDs.
Pain management -gabapentin or pregabalin for neuropathic pain. Opioids if severe. Pain is often undertreated.
Why do you check FVC and not just ABG for respiratory monitoring in GBS?
The ABG is a lagging indicator of respiratory failure in neuromuscular disease. Patients with progressive diaphragm weakness compensate by increasing respiratory rate → they maintain normal PaO₂ and PaCO₂ until they're nearly exhausted. When the CO₂ finally rises on ABG, they're about to arrest. FVC (forced vital capacity) is a leading indicator -it declines progressively as respiratory muscles weaken, well before gas exchange deteriorates.
What is the 20/30/40 rule in GBS and why is FVC more important than SpO₂?
The 20/30/40 rule predicts the need for intubation: FVC < 20 mL/kg, NIF < −30 cmH₂O, or FVC decline > 30% from baseline. Additionally, bulbar dysfunction (inability to swallow, weak cough) independently warrants intubation. SpO₂ is a late and unreliable sign -a patient with GBS can have normal SpO₂ until minutes before respiratory arrest because their lungs are normal; the problem is the respiratory muscles.
What are the differences between IVIG and plasmapheresis (PLEX) for GBS?
Both are equally effective -Hughes, 2014 Cochrane showed no significant difference in outcomes. IVIG: 0.4 g/kg/day × 5 days. Advantages: easier to administer, no special equipment, can do on general floor. Disadvantages: headache, aseptic meningitis, renal failure (sucrose-containing formulations), thrombotic events. PLEX: 5 exchanges over 1-2 weeks. Advantages: faster onset of improvement in some studies.
Can you use steroids in GBS?
No -steroids do NOT help GBS and may be harmful. This is a common mistake because GBS is autoimmune and steroids work in many autoimmune conditions. However, multiple RCTs and Cochrane reviews have shown corticosteroids do not improve outcomes and may delay recovery. The reason is unclear -GBS inflammation involves different immune pathways (complement-mediated, macrophage-mediated demyelination) than conditions responsive to steroids.
Clinical Examples
📋 Case 1, Classic AIDP with Respiratory Compromise
Patient: 42M with ascending bilateral leg weakness × 4 days, now unable to walk. Had Campylobacter gastroenteritis 2 weeks ago. Areflexic throughout. Bilateral facial weakness. FVC 22 mL/kg (declining from 30 mL/kg 12h ago).
Teaching point: Serial FVC is the most critical measurement in GBS, not SpO₂. By the time SpO₂ drops, the patient is in extremis. The "20-30-40 rule" provides objective intubation thresholds. ~30% of GBS patients require mechanical ventilation.
📋 Case 2, Miller Fisher Syndrome
Patient: 55F with 3 days of double vision, unsteady gait, and bilateral ptosis. Areflexia. No limb weakness. Recent URI 2 weeks ago. MRI brain normal.
Key findings: Miller Fisher syndrome triad: ophthalmoplegia + ataxia + areflexia. A GBS variant. Anti-GQ1b antibodies positive in > 90%. Does NOT typically cause limb weakness or respiratory failure (unlike classic GBS).
Management:
IVIG 0.4 g/kg/day × 5 days (standard treatment, though most cases self-resolve)
Check anti-GQ1b antibodies (confirmatory, highly specific for Miller Fisher)
Monitor FVC despite no limb weakness (overlap with GBS can develop, 5-10% progress to AIDP)
LP: albuminocytologic dissociation (elevated protein, normal WBC), same as classic GBS
Prognosis excellent: most recover fully within 2-3 months without residual deficits
Teaching point: Miller Fisher is the most common GBS variant. The triad of ophthalmoplegia + ataxia + areflexia after a viral infection should trigger immediate GQ1b testing and admission for FVC monitoring, even though prognosis is better than classic AIDP.
📋 Case 3, GBS vs CIDP Diagnostic Dilemma
Patient: 60M with progressive proximal and distal weakness over 3 months. Initially diagnosed as GBS 10 weeks ago and treated with IVIG, improved briefly then relapsed. Now wheelchair-bound. Areflexic. No preceding infection.
Key findings: Progression > 8 weeks = by definition NOT GBS (GBS peaks by 4 weeks). This is CIDP (chronic inflammatory demyelinating polyneuropathy). The relapse after IVIG and chronic course are diagnostic clues. CIDP responds to steroids (unlike GBS).
IVIG 2 g/kg over 2-5 days (alternative first-line, some patients prefer to avoid steroids)
If steroid/IVIG-refractory: PLEX, rituximab, or other immunosuppressants
Long-term maintenance therapy often required (CIDP is chronic, relapsing)
Teaching point: The critical distinction: GBS = monophasic, peaks ≤ 4 weeks, steroids DON'T work. CIDP = chronic/relapsing, progresses > 8 weeks, steroids DO work. Any "GBS" that relapses or progresses beyond 8 weeks should be reclassified as CIDP.
📣 Sample Presentation
One-Liner
"Mr. Fernandez is a 45-year-old presenting with 5 days of ascending bilateral leg weakness and paresthesias following a diarrheal illness 3 weeks ago. Areflexic on exam. FVC 28 mL/kg."
Intubate if FVC < 20 mL/kg or declining > 30% from baseline. FVC is the vital sign in GBS -do NOT rely on SpO2 or ABG (lagging indicators).
NIF (negative inspiratory force)
q4–6h (with FVC)
Intubate if weaker than -20 to -30 cmH2O. Declining NIF indicates diaphragmatic weakness.
HR / BP (autonomic dysfunction)
Continuous telemetry
Labile BP, tachycardia/bradycardia, arrhythmias in ~70% of GBS. Avoid beta-blockers (can worsen bradycardia episodes). Gentle fluid management for BP lability. Note: this is autonomic dysfunction, not autonomic dysreflexia (which is a spinal cord injury phenomenon).
I&Os (neurogenic bladder)
Strict
Urinary retention is common from autonomic dysfunction. Monitor for distension. May need intermittent catheterization or Foley.
Daily neuro exam
Daily (at minimum)
Track progression: proximal vs distal strength (MRC scale), cranial nerve function, bulbar weakness (swallowing, cough). Nadir typically at 2–4 weeks.
Pain assessment
Each shift
Neuropathic pain in ~60% -often undertreated. Use gabapentin or pregabalin. Opioids if severe.
The 20/30/40 rule: Intubate if FVC < 20 mL/kg, NIF < -30 cmH2O, or FVC decline > 30%. By the time ABG shows respiratory acidosis, you are too late for a controlled intubation.
🧪 Workup
Workup
LP -high protein, normal WBC
NCS/EMG -demyelinating vs axonal
FVC q4-6h -intubate <20mL/kg
NIF -intubate <−30
Anti-ganglioside Ab
MRI spine -rule out cord compression
💊 Medications
Medications -Guillain-Barre Syndrome
Drug
Dose
Route
Notes
IMMUNOTHERAPY (choose ONE)
IVIG PREFERRED
0.4 g/kg/day x 5 days
IV
Preferred due to easier administration. Check IgA level first (IgA-deficient → anaphylaxis risk). Side effects: headache, renal failure, aseptic meningitis, thrombotic events.
Plasma exchange (PLEX)
5 sessions over 2 weeks
IV (large-bore access)
Equivalent efficacy to IVIG. Use if IVIG contraindicated. Requires central access. More hemodynamic effects.
Do NOT combine IVIG + PLEX (PLEX removes IVIG). Steroids are NOT effective in GBS.
SUPPORTIVE CARE
Gabapentin (Neurontin)
100–900 mg TID, titrate up
PO
Neuropathic pain -first-line. Pain is present in ~60% and often undertreated.
Pregabalin (Lyrica)
75–150 mg BID
PO
Alternative to gabapentin for neuropathic pain.
Enoxaparin (Lovenox) MANDATORY
40 mg SQ daily
SQ
DVT prophylaxis is mandatory. Immobile patients at very high VTE risk. Add SCDs. Continue until ambulatory.
RoundsRx Infographic Series · #90 · Neurology · PDF 156 KB
Related Topics
Altered Mental Status & DeliriumHeadache & MigraineHeat StrokeIntracerebral HemorrhageMyasthenic CrisisNMS vs Serotonin Syndrome
EMERGENTNeurology
Myasthenic Crisis
Myasthenia gravis exacerbation with respiratory failure requiring intubation. Triggered by infection, surgery, medication changes, or drug interactions. Same respiratory monitoring as GBS -FVC < 20 → intubate. Know the drugs that worsen MG.
🔍 Overview
Myasthenia Gravis -Key Concepts
Autoantibodies against AChR (acetylcholine receptor) at the neuromuscular junction → fatigable weakness
Fatigable: weakness worsens with repeated use and improves with rest. Worse at end of day.
Excessive (SLUDGE: salivation, lacrimation, urination, diarrhea, GI cramping, emesis)
Fasciculations
Absent
Present
Response to edrophonium
Improves
Worsens
Treatment
IVIG or PLEX + immunosuppression
Hold pyridostigmine, atropine for secretions
🚨 Management
Myasthenic Crisis Treatment
Respiratory
FVC + NIF q4–6h. Same 20/30/40 rule as GBS. Intubate if FVC < 20 mL/kg or NIF < −30. Avoid succinylcholine and minimize non-depolarizing agents. BiPAP can bridge but do NOT delay intubation if deteriorating.
Rapid immunotherapy
IVIG 0.4 g/kg/day × 5 days OR plasmapheresis × 5 exchanges. Both equally effective. PLEX onset is faster (~24–48h) vs IVIG (3–5 days). Choose based on availability and access.
Steroids
Start high-dose steroids (prednisone 1 mg/kg/day or methylprednisolone 1g IV × 3–5 days). Warning: steroids can cause transient worsening in the first 1–2 weeks → always start WITH IVIG/PLEX, not alone in crisis.
Cholinesterase inhibitor
Hold pyridostigmine during crisis (increased secretions worsen respiratory status, and it may contribute to cholinergic crisis). Resume when improving and extubated.
Trigger
Identify and treat the trigger: infection (#1 -pneumonia, UTI), medication change, surgery, emotional stress. Review medication list for MG-exacerbating drugs.
Chronic MG Management
Drug
Role
Notes
Pyridostigmine (Mestinon) SYMPTOMATIC
AChE inhibitor -increases ACh at NMJ
First-line symptomatic treatment. 60 mg PO TID, titrate. Does NOT alter disease course -only improves symptoms.
Prednisone (Deltasone)
Immunosuppression
Most patients need immunosuppression beyond pyridostigmine. Start low, escalate slowly (risk of initial worsening).
Azathioprine (Imuran)
Steroid-sparing agent
Takes 6–12 months to work. Check TPMT before starting (deficiency → myelosuppression).
Mycophenolate (CellCept)
Steroid-sparing agent
Alternative to azathioprine. Common choice. Teratogenic.
Rituximab (Rituxan)
Anti-CD20 -refractory MG
Especially effective in anti-MuSK MG. Growing evidence for AChR+ refractory disease.
Efgartigimod (Vyvgart)
FcRn inhibitor -reduces pathogenic IgG
ADAPT, 2021: improved MG-ADL by ≥ 2 points in 67.7% vs 29.7% placebo. IV infusion cycles.
Thymectomy
Surgical -removes pathogenic antigen source
Indicated if thymoma. Also beneficial in AChR+ non-thymomatous MG < 65 yrs (MGTX, 2016). Response takes months.
🧪 Workup
Workup
AChR Ab (~85%)
MuSK Ab if AChR neg
CT chest -thymoma
PFTs (FVC, NIF)
Ice pack test -ptosis improvement
💊 Medications
Medications
Drug
Dose
Route
Notes
Pyridostigmine
60mg q4-6h
PO
AChE inhibitor
Prednisone
Start low, titrate
PO
Can worsen MG initially
Azathioprine
2-3mg/kg/day
PO
Steroid-sparing
IVIG
0.4g/kg×5d
IV
Crisis
Rituximab
375mg/m²
IV
Refractory
📋 On Rounds
Why should you avoid IV magnesium in myasthenia gravis?
Magnesium acts as a calcium channel blocker at the neuromuscular junction -it inhibits presynaptic calcium-dependent acetylcholine release and reduces postsynaptic sensitivity to ACh. In a patient with MG (where ACh receptor density is already reduced by autoantibodies), adding magnesium further impairs neuromuscular transmission → can precipitate myasthenic crisis and respiratory failure.
What medications are contraindicated in myasthenia gravis and why?
Several common medications can precipitate or worsen myasthenic crisis by impairing neuromuscular transmission: (1) Aminoglycosides (gentamicin, tobramycin) -block presynaptic Ca²⁺ channels → reduced ACh release. (2) Fluoroquinolones -same mechanism, plus direct NMJ blockade. (3) Beta-blockers -impair NMJ safety factor. (4) Magnesium -blocks presynaptic Ca²⁺ channels (don't aggressively replete Mg in MG patients).
What is cholinergic crisis and how do you differentiate it from myasthenic crisis?
Both present with weakness and respiratory failure, but the mechanism is opposite. Myasthenic crisis: under-treated MG → insufficient ACh at NMJ → weakness. Pupils: normal or dilated. Secretions: dry. Responds to: edrophonium/neostigmine (improves). Cholinergic crisis: over-treated with pyridostigmine → excess ACh → depolarization block + muscarinic effects. Pupils: miotic (small).
How do you differentiate MG from Lambert-Eaton syndrome?
MG: autoantibodies against post-synaptic AChR → fatigable weakness that WORSENS with repetitive use, proximal > distal, bulbar symptoms (ptosis, diplopia, dysphagia) prominent, reflexes normal. EMG: decremental response on repetitive nerve stimulation. Lambert-Eaton (LEMS): autoantibodies against pre-synaptic voltage-gated calcium channels (P/Q type)
Clinical Examples
📋 Case 1, Myasthenic Crisis
Patient: 58F with known AChR Ab+ MG on pyridostigmine 60 mg QID. Admitted with worsening dyspnea and dysphagia after UTI (treated with ciprofloxacin). FVC 14 mL/kg (declining). Bilateral ptosis, weak neck flexion, nasal speech.
Key findings: Myasthenic crisis: respiratory failure from MG exacerbation. Triggered by UTI (infection is #1 precipitant) + ciprofloxacin (fluoroquinolones worsen NMJ transmission). FVC < 20 = intubation threshold.
Management:
ICU admission, check FVC q4h (same monitoring protocol as GBS)
IVIG 0.4 g/kg/day × 5 days OR PLEX q other day × 5 sessions (both equally effective)
STOP ciprofloxacin, switch to a non-NMJ-affecting antibiotic (ceftriaxone, TMP-SMX)
HOLD pyridostigmine during crisis (excess secretions complicate airway management)
Intubate if FVC < 15 mL/kg, declining rapidly, or unable to handle secretions, use non-depolarizing NMB (avoid succinylcholine, MG patients are resistant)
Teaching point: The most common trigger for myasthenic crisis is infection, not medication non-compliance. Always review the med list, fluoroquinolones, aminoglycosides, beta-blockers, and magnesium can precipitate crisis. The MG medication "hit list" should be at every bedside.
📋 Case 2, New Diagnosis of MG with Thymoma
Patient: 45M with 3 months of fluctuating diplopia, ptosis (worse in evening), difficulty chewing steak. Ice pack test: ptosis improves bilaterally. AChR antibodies positive. CT chest: anterior mediastinal mass 4 cm.
Key findings: New MG with thymoma, ~15% of MG patients have thymoma, and ~30% of thymoma patients develop MG. Thymectomy is indicated for ALL thymomas regardless of MG severity, plus for non-thymomatous MG per MGTX trial.
Management:
Start pyridostigmine 60 mg PO TID (symptomatic relief, first-line)
CT-guided biopsy of mediastinal mass → staging
Thymectomy: robotic or open, both curative for thymoma + improves MG outcomes MGTX, 2016
Pre-op optimization: may need IVIG or PLEX before surgery (reduce perioperative myasthenic crisis risk)
Start prednisone LOW (10 mg, titrate up slowly), high-dose steroids can transiently worsen MG in first 2 weeks
Teaching point: Always get CT chest in new MG, thymoma is present in 15%. The MGTX trial showed thymectomy improves outcomes even in NON-thymomatous MG (AChR Ab+, age 18-65). Prednisone must be started low and titrated slowly to avoid initial worsening.
Key findings: MuSK-positive MG, distinct phenotype: bulbar and facial predominance, tongue/facial atrophy, poor response to pyridostigmine (often makes symptoms worse), and no benefit from thymectomy.
Management:
Stop pyridostigmine (MuSK-MG often worsens with AChE inhibitors)
Rituximab is emerging as first-line for MuSK-MG (excellent response rate ~70-80%)
PLEX preferred over IVIG for acute exacerbations (MuSK antibodies are IgG4, not efficiently removed by IVIG)
Prednisone + mycophenolate as standard immunosuppression
No thymectomy (thymoma is extremely rare in MuSK-MG, and thymectomy does not improve outcomes)
Teaching point: MuSK-MG breaks all the rules of AChR-MG: pyridostigmine worsens it, thymectomy doesn't help, IVIG is less effective than PLEX, and rituximab works better than traditional immunosuppressants. Always check MuSK antibodies if AChR is negative.
📣 Sample Presentation
One-Liner
"Mrs. Park is a 60-year-old with AChR Ab+ myasthenia gravis on pyridostigmine who presents with worsening dyspnea and dysphagia after a UTI. FVC 16 mL/kg. Diagnosed with myasthenic crisis."
Key Points to Cover on Rounds
Myasthenic crisis triggered by UTI. FVC 16 mL/kg (<20 → intubated for airway protection). NIF −18 cmH₂O. Treatment: IVIG 0.4 g/kg/day × 5 days. Pyridostigmine HELD during crisis (excess secretions worsen airway). Antibiotics for UTI: switched from ciprofloxacin → ceftriaxone (fluoroquinolones contraindicated in MG). Offending meds reviewed -no aminoglycosides, no BB, no Mg supplementation. Methylprednisolone 1g IV × 3 days (cautious -steroids can transiently worsen MG in first 7-10 days). Plan: daily FVC/NIF, restart pyridostigmine when improving and extubated.
Monitoring
FVC every visit
Med review -avoid aminoglycosides, FQs, BB, Mg
Thymoma surveillance
Infection screening on immunosuppression
⚡ Summary
Summary
Define the Crisis by the Respiratory Numbers
Myasthenic crisis is an exacerbation with respiratory failure requiring ventilatory support.Follow FVC and negative inspiratory force serially, not the oxygen saturation: neuromuscular respiratory failure gives normal saturations until the patient is nearly apneic. FVC below about 20 mL/kg, NIF weaker than -30, or a falling trend means intubate.
Intubate Early, Electively
Do not wait for hypercapnia or exhaustion. A controlled intubation with a full team is far safer than a crash airway in a patient who has just lost their bulbar function. Bulbar weakness with aspiration is an indication in its own right, independent of the vital capacity.
Know the Drugs That Precipitate It
Aminoglycosides, fluoroquinolones, macrolides, beta blockers, magnesium, neuromuscular blockers, and iodinated contrast.Magnesium given for eclampsia or hypomagnesemia can precipitate crisis, and it is one of the commonest inadvertent triggers on a medical ward. Review every new drug against the list.
Find the Trigger
Infection is the commonest, then surgery, pregnancy, tapering immunosuppression, and a new drug.Treat the infection aggressively, choosing antibiotics that do not worsen the disease. A crisis with no identified trigger should prompt a search for thymoma and for a coexisting thyroid disorder.
Plasma Exchange or IVIG, Plus Steroids
Both work and both act within days.Plasma exchange is often faster but needs vascular access and causes hemodynamic shifts; IVIG is easier but carries thrombosis, renal and volume risks.Start high-dose steroids at the same time for the durable effect, warning that steroids cause a transient worsening in the first 1 to 2 weeks, which is why they are started under respiratory monitoring.
Hold the Cholinesterase Inhibitor in Crisis
Pyridostigmine is usually stopped in a ventilated patient in crisis: it increases secretions, which worsens the airway situation, and it contributes to the diagnostic confusion with cholinergic crisis. Restart it as the patient recovers.
Distinguish Cholinergic Crisis
Cholinergic crisis comes from excess cholinesterase inhibitor and adds muscarinic features: SLUDGE (salivation, lacrimation, urination, diarrhea, GI upset, emesis), miosis, bradycardia and fasciculations. Myasthenic crisis has none of those and improves with more treatment; cholinergic crisis worsens.When in doubt, hold the pyridostigmine and support the airway, which is safe in both.
Plan the Long-Term Regimen Before Discharge
Pyridostigmine for symptoms plus a steroid-sparing agent (azathioprine, mycophenolate) for maintenance, with newer targeted options (rituximab, complement and FcRn inhibitors) for refractory disease. CT the chest for thymoma, and consider thymectomy, which improves outcomes in generalized AChR-antibody-positive disease (MGTX). Give the patient a written list of drugs to avoid, since the next crisis is most often triggered by a prescription written elsewhere.
Core temperature >40°C (104°F) with CNS dysfunction (altered mental status, seizures, coma). A true medical emergency -mortality 10–50% depending on delay to cooling. The single most important intervention is rapid cooling to <39°C within 30 minutes. Every minute counts.
🔍 Overview
Classification
Type
Setting
Mechanism
Key Features
Classic (non-exertional)
Elderly, chronic illness, medications, heat waves
Failure of thermoregulation -body cannot dissipate environmental heat
Develops over days. Skin often hot and dry (sweat glands exhausted). Elderly on anticholinergics, diuretics, beta-blockers at highest risk.
The defining feature of heat stroke is CNS dysfunction -not the temperature alone. A patient with temp 40.5°C and normal mentation has heat exhaustion. A patient with temp 40.1°C and confusion/seizures has heat stroke. Treat the brain, not the thermometer.
Beta-blockers -blunt cardiac output response to heat stress
Stimulants -amphetamines, cocaine, MDMA increase metabolic heat production
Antipsychotics -impair thermoregulation centrally (especially in NMS overlap)
Extremes of age -elderly (impaired thermoregulation) and infants (high surface area:volume)
Obesity, deconditioning, dehydration
🚨 Management
Cooling -The Single Most Important Intervention
Target: core temperature < 39°C (102.2°F) within 30 minutes. Every minute of delay increases mortality and neurological injury. Start cooling BEFORE full workup. Do NOT wait for labs.
Method
Technique
Effectiveness
Notes
Cold water immersion GOLD STANDARD
Immerse body (neck down) in ice water bath (1–3°C)
Cooling rate ~0.2°C/min -fastest available method
Gold standard for exertional heat stroke. Near-zero mortality if applied within 30 min. Logistically challenging in ED -need large tub. Monitor for shivering (counterproductive).
Evaporative cooling
Undress patient, mist with lukewarm water, fan continuously
Cooling rate ~0.05°C/min
Most practical in ED/ICU. Less effective than immersion but widely available. Combine with ice packs to axillae, groin, neck.
Ice packs
Apply to axillae, groin, neck, and scalp (high blood flow areas)
Adjunct -slow as standalone
Use in combination with other methods. Cover large surface area. Rotate frequently.
Cold IV fluids
4°C normal saline bolus (not iced -just refrigerated)
Adjunct -modest cooling effect
Addresses volume depletion AND provides some cooling. Give 1–2L bolus. Do not use as sole cooling method.
Invasive cooling
Peritoneal lavage, bladder irrigation with cold saline, endovascular cooling catheter
Variable -reserved for refractory cases
Consider if temp >41°C and not responding to external cooling. Endovascular catheter allows precise temperature control.
Stepwise Approach
ABCs first -secure airway if GCS ≤ 8, intubate if needed
Remove from heat -move to cool environment, remove clothing
Begin cooling immediately -cold water immersion if available, otherwise evaporative + ice packs
IV access + fluids -cold NS or LR 1–2L bolus. LR is safe even in liver disease (lactate is metabolized by kidneys and skeletal muscle, not just liver).
Continuous core temperature monitoring -rectal or esophageal probe (NOT oral or axillary -inaccurate)
Stop cooling at 39°C -overshoot hypothermia is a real risk
Avoid antipyretics -acetaminophen and NSAIDs do NOT work. Heat stroke is not a fever (no prostaglandin-mediated set point elevation). Antipyretics may worsen hepatic/renal injury.
Do NOT give antipyretics (acetaminophen, NSAIDs). Heat stroke is a failure of thermoregulation, not a prostaglandin-mediated fever. The hypothalamic set point is normal -the body simply cannot dissipate heat. Antipyretics are useless and hepatotoxic in this setting.
🧪 Workup
Diagnostic Evaluation
Core temperature -rectal or esophageal probe. Oral/axillary/temporal are unreliable. Must be >40°C for diagnosis.
LFTs -AST/ALT elevation is universal. Hepatic injury peaks at 48–72h. Fulminant liver failure is a major cause of death.
CK (creatine kinase) -rhabdomyolysis (CK >5× ULN). Peak at 24–72h. Check q6–12h.
Coagulation panel -PT/INR, PTT, fibrinogen, D-dimer. DIC is common and a major cause of death.
Lactate -marker of tissue hypoperfusion and anaerobic metabolism.
UA with myoglobin -dark urine, positive blood on dipstick but no RBCs on microscopy = myoglobinuria.
ABG/VBG -mixed acid-base disturbances common (respiratory alkalosis from tachypnea + metabolic acidosis from lactic acid).
CT head -if focal neurological deficits or seizures to rule out structural cause.
LFTs may be initially normal. Hepatic injury from heat stroke peaks at 48–72 hours. Recheck LFTs daily for 3–5 days. Fulminant hepatic failure requiring transplant can occur.
💊 Medications
Key Medications
Drug
Dose
Role
Notes
Normal Saline (cold, 4°C) 1ST LINE
1–2 L IV bolus
Volume resuscitation + adjunct cooling
Most patients are severely volume depleted. LR or NS are both acceptable -LR is safe even in liver disease (lactate is metabolized by kidneys and muscle, not just liver). Titrate to UOP 1–2 mL/kg/h (especially if rhabdo).
Lorazepam (Ativan)
2–4 mg IV PRN
Seizures, shivering
Shivering during cooling is counterproductive (generates heat). Benzos suppress shivering. Also first-line for heat stroke seizures.
Dantrolene CONSIDER
1–2.5 mg/kg IV
Refractory hyperthermia
Skeletal muscle relaxant. Consider if NMS or malignant hyperthermia cannot be excluded. Evidence for pure heat stroke is limited, but may help if significant muscle rigidity/rhabdo.
Sodium Bicarbonate
150 mEq in 1L D5W
Urine alkalinization for rhabdomyolysis
Target urine pH >6.5 to prevent myoglobin-induced AKI. Use if CK >5,000 and rising.
Medications that are CONTRAINDICATED or USELESS: Acetaminophen (no effect, hepatotoxic), NSAIDs (no effect, nephrotoxic), aspirin (no effect, worsens DIC), phenytoin (ineffective for hyperthermic seizures -use benzos).
📋 On Rounds
Pimp Questions
Why don't antipyretics work in heat stroke?
Fever is caused by prostaglandins raising the hypothalamic set point -antipyretics (acetaminophen, NSAIDs) work by blocking prostaglandin synthesis. In heat stroke, the hypothalamic set point is normal -the body simply cannot dissipate the heat load fast enough (overwhelmed thermoregulatory system). Since there is no prostaglandin-mediated set point elevation, antipyretics have zero effect.
What is the key difference between heat stroke and heat exhaustion?
CNS dysfunction. Heat exhaustion can cause fatigue, nausea, headache, and even syncope -but mental status remains intact. Heat stroke is defined by altered mental status (confusion, delirium, seizures, coma) + core temp >40°C. Heat exhaustion is a clinical continuum that can progress to heat stroke if not treated. The moment a patient develops AMS in the setting of hyperthermia, it's heat stroke until proven otherwise.
What is the gold standard cooling method and what cooling rate does it achieve?
Cold water immersion (ice water bath, 1–3°C) is the gold standard. Cooling rate ~0.2°C/min, which means a patient at 42°C can reach target (39°C) in ~15 minutes. Near-zero mortality when applied within 30 minutes. Compare with evaporative cooling (~0.05°C/min) -significantly slower. The military and sports medicine literature strongly supports ice water immersion as first-line.
How do you differentiate heat stroke from neuroleptic malignant syndrome (NMS)?
NMS presents with hyperthermia + AMS + lead-pipe rigidity + autonomic instability, typically after starting or increasing a dopamine antagonist (antipsychotics, metoclopramide). Key distinguishing features: (1) NMS has prominent muscle rigidity (heat stroke has flaccidity or mild rigidity), (2) NMS develops over days (exertional heat stroke over hours), (3) NMS has markedly elevated CK from rigidity
📣 Sample Presentation
One-Liner
"Mr. Thompson is a 22-year-old Army recruit who collapsed during a 10-mile run in 95°F heat, found unresponsive with rectal temp 41.8°C, GCS 7, tachycardic to 140, and diffusely diaphoretic."
Key Points to Cover on Rounds
Exertional heat stroke -core temp 41.8°C on arrival, GCS 7. Ice water immersion initiated in field within 15 min, continued in ED. Core temp down to 39.2°C at 20 min, cooling stopped at 38.8°C. Now GCS 11 (E3V3M5), improving. CK 12,400 and rising -aggressive IVF at 250 mL/hr with bicarb drip for urine alkalinization, target UOP >200 mL/h. LFTs: AST 320, ALT 180 -will recheck daily (peaks at 48–72h). Coags normal, no DIC. Lactate 6.2 → 3.1 trending down. Plan: ICU, continuous core temp monitoring, CK q6h, LFTs daily, neuro checks q2h, hold all nephrotoxins.
Monitoring Parameters
Continuous core temperature -rectal or esophageal probe. Stop active cooling at 39°C to prevent overshoot hypothermia.
Continuous telemetry -arrhythmias from hyperkalemia, hyperthermia-induced myocardial injury.
Heat stroke is hyperthermia plus altered mental status; heat exhaustion is hyperthermia with intact mentation.A patient at 40.5°C who is thinking clearly has heat exhaustion; a patient at 40.1°C who is confused or seizing has heat stroke.Treat the brain, not the thermometer.
Cool Immediately, Before the Workup
Target a core temperature below 39°C within 30 minutes.Every minute of delay increases mortality and neurologic injury, because the duration and degree of hyperthermia together determine the protein denaturation and cell death. Start cooling before the labs, before imaging, before the full history.
Cold Water Immersion Is the Best Method
It cools fastest and has the lowest mortality in exertional heat stroke.Evaporative cooling with misting and fans is the practical alternative in the elderly or when immersion is impractical, along with ice packs to the neck, axillae and groin, and cold IV fluids. Stop at about 38.5 to 39°C to avoid overshoot into hypothermia.
Do Not Give Antipyretics
Acetaminophen and NSAIDs do nothing.Heat stroke is a failure of heat dissipation, not a prostaglandin-mediated fever, and the hypothalamic set point is normal. Worse, both add hepatic and renal toxicity to organs that are already injured by the hyperthermia.
Do Not Give Dantrolene Either
It is the treatment for malignant hyperthermia and neuroleptic malignant syndrome, not for classic or exertional heat stroke, where it has shown no benefit. Consider those diagnoses instead when the history involves an anesthetic, succinylcholine or an antipsychotic, since the treatments genuinely differ.
Sedate for Shivering
Shivering during cooling generates heat and defeats the intervention. Use benzodiazepines, which also treat the agitation and seizures that accompany the syndrome. This is one of the commonest reasons active cooling appears to fail.
Separate Classic From Exertional
Classic: elderly, chronically ill, during a heat wave, often anhidrotic with hot dry skin, developing over days.Exertional: young, fit, exercising in the heat, frequently still sweating, so the presence of sweat does not exclude heat stroke. Exertional cases have far more rhabdomyolysis, DIC and acute kidney injury.
Anticipate Multi-Organ Failure
Rhabdomyolysis with acute kidney injury, hepatic injury, DIC, ARDS and arrhythmia.Give aggressive fluids and follow CK, renal function, liver tests, coagulation and electrolytes serially.Review the drugs that predisposed them: anticholinergics, antipsychotics, diuretics, beta blockers and stimulants all impair heat dissipation, and counsel about them before discharge.
RoundsRx Infographic Series · #108 · Toxicology & Emergencies · PDF 146 KB
Related Topics
Altered Mental Status & DeliriumGuillain-Barré SyndromeHeadache & MigraineIntracerebral HemorrhageMyasthenic CrisisNMS vs Serotonin Syndrome
EmergentEM
Chest Pain Workup
The most common ED complaint. Your job: rapidly rule out the five life-threatening causes before anything else. ECG within 10 minutes. Most chest pain is benign -but the 5% that isn't will kill if missed.
🔍 Overview
5 Life-Threatening Causes -Rule These Out First
Diagnosis
Key Features
Critical Action
ACS (STEMI/NSTEMI)
Substernal pressure, exertional, radiates to jaw/arm, diaphoresis, nausea. Risk factors: age, DM, HTN, smoking, family hx.
ECG within 10 min. Troponin. See STEMI / NSTEMI.
Aortic dissection
Tearing/ripping pain, maximal at onset, radiating to back. BP differential, pulse deficit, new AR murmur.
CTA chest/abdomen. BP/HR control. See Aortic Dissection.
Pulmonary embolism
Pleuritic pain, dyspnea, tachycardia out of proportion. Risk: immobility, surgery, cancer, OCP.
Clinical diagnosis → needle decompression. See Pneumothorax.
Esophageal rupture (Boerhaave)
Severe retrosternal pain after forceful vomiting. Subcutaneous emphysema, Hamman's crunch (mediastinal crackle). Left pleural effusion.
CT chest with oral contrast or water-soluble esophagram. Emergent surgical consult. Mortality > 50% if delayed > 24h.
ECG within 10 minutes of arrival. Do NOT wait for lab results, triage, or full history before obtaining an ECG. A STEMI diagnosis changes everything - door-to-balloon time < 90 min saves myocardium. If initial ECG is nondiagnostic but suspicion remains high, repeat in 15-30 minutes.
Common Non-Emergent Causes
Category
Diagnosis
Clues
Musculoskeletal (~35%)
Costochondritis, muscle strain
Reproducible with palpation, worse with movement/position, no cardiac risk factors. Most common cause of chest pain in ED.
GI (~15%)
GERD, esophageal spasm, PUD
Burning, postprandial, relieved by antacids. Esophageal spasm can mimic ACS (substernal, relieved by NTG).
Pulmonary
Pneumonia, pleuritis, asthma
Pleuritic (sharp, worse with inspiration), fever, cough, focal exam findings.
PE (if negative + low Wells → ruled out). Do NOT order if high pretest → go straight to CTPA.
CTPA
PE suspected (high Wells, positive D-dimer)
PE. Also shows dissection incidentally.
CTA chest
Dissection suspected
Aortic dissection. Triple rule-out CTA can assess coronaries + PE + dissection in one scan (but requires specific protocol).
HEART Score for Chest Pain Disposition
See NSTEMI topic for full HEART score. Score 0–3: safe for early discharge (< 2% MACE). Score 7–10: high risk → early invasive.
High-sensitivity troponin changes practice: hs-cTnI can rule out MI with a single draw if < 5 ng/L (99% NPV) HiSTORIC, 2019. Serial troponins (0h/1h or 0h/3h protocol) are standard. Delta troponin matters more than absolute value for detecting acute injury vs chronic elevation (CKD, HF).
🚨 Management
Management
ACS: ASA+heparin+serial troponin+cardiology
PE: Wells→D-dimer or CTPA
Dissection: CTA. A→surgery. B→HR/BP control.
Tamponade: echo→pericardiocentesis
Tension PTX: needle decompress→tube
HEART 0-3 + 2 neg troponins → safe discharge
Key Evidence: The HEART score safely identifies low-risk chest pain patients for early discharge HEART Pathway, 2015. High-sensitivity troponin 0h/1h protocol can safely rule out MI in ED ESC 0h/1h Algorithm, 2020. CCTA is an alternative to stress testing for intermediate-risk chest pain PROMISE, 2015SCOT-HEART, 2018.
Safe discharge criteria: HEART score 0-3 + negative serial troponins (at least 2 draws, 3h apart) + nonischemic ECG + resolution of symptoms. Arrange outpatient stress test or cardiology follow-up within 72h. Prescribe ASA and NTG SL PRN. Clear return precautions: "Come back immediately if chest pain returns, worsens, or spreads."
📋 On Rounds
Can NTG relief differentiate cardiac from non-cardiac chest pain?
No. This is a common myth. NTG relieves pain from ACS (coronary vasodilation + preload reduction) but also relieves esophageal spasm (smooth muscle relaxation). Henrikson, 2003: NTG response had no predictive value for cardiac vs non-cardiac chest pain. Patients with documented ACS failed to respond to NTG in ~35% of cases, while patients with non-cardiac pain responded in ~40%. Do NOT use NTG response to rule in or rule out ACS.
What are the 5 'must-not-miss' causes of chest pain?
What is the HEART score and how does it change your management?
HEART score = History (0-2) + ECG (0-2) + Age (0-2) + Risk factors (0-2) + Troponin (0-2). Total 0-10. 0-3 (low risk): 1.6% risk of MACE at 30 days → safe for early discharge with outpatient follow-up. Consider stress test outpatient. 4-6 (moderate): 12% risk → observe, serial troponins, consider stress test or CT coronary angiography before discharge PROMISE, 2015. 7-10 (high): 65% risk → admit, heparin, cardiology consult, likely cath.
What are the classic ECG findings that differentiate pericarditis from STEMI?
Pericarditis: diffuse ST elevation (not territorial), PR depression (most specific finding), concave-up ("smiley face") ST morphology, reciprocal ST depression + PR elevation in aVR only. STEMI: territorial ST elevation (corresponds to coronary artery territory -e.g., II/III/aVF = inferior = RCA), convex-up ("tombstone") morphology, reciprocal ST depression in opposite leads, Q waves may develop.
What is the HEART score and how does it guide disposition?
HEART = History, ECG, Age, Risk factors, Troponin. Each scored 0-2, total 0-10. 0-3 (low risk): consider discharge with outpatient follow-up. 4-6: observation, serial troponins. 7-10 (high risk): admit for invasive strategy. The HEART Pathway, 2015 safely reduced admissions by 20% vs standard care.
Clinical Examples
📋 Case 1, NSTEMI with High HEART Score
Patient: 64-year-old man with DM, HTN, and hyperlipidemia presents with 3 hours of substernal pressure radiating to the left arm. Diaphoretic, nauseous. BP 148/92, HR 88.
Key findings: ECG: ST depression in V3-V6 and I/aVL. Troponin 0.48 (elevated), repeat at 3h: 1.24 (rising). HEART score 8.
Metoprolol 25 mg PO (HR/BP allow), atorvastatin 80 mg PO
Cardiology consult for early invasive strategy (cath within 24h)
Continuous telemetry, serial ECGs with recurrent symptoms
Teaching point: HEART score 7-10 = 65% risk of MACE at 30 days. Rising troponin pattern confirms acute myocardial injury. Early invasive strategy with cath is indicated. TIMACS, 2009
📋 Case 2, Acute Pericarditis
Patient: 32-year-old previously healthy man presents with sharp pleuritic chest pain worse when lying supine, improved by leaning forward. Recent URI 1 week ago. Low-grade fever 38.1C.
Key findings: ECG: diffuse concave-up ST elevation with PR depression in limb leads, reciprocal PR elevation and ST depression in aVR. Troponin mildly elevated at 0.08 (myopericarditis). Echo: small circumferential pericardial effusion without tamponade physiology.
Activity restriction until symptom resolution and CRP normalization
Avoid anticoagulation (risk of hemorrhagic pericarditis)
Teaching point: PR depression is virtually pathognomonic for pericarditis and is never seen in STEMI. Diffuse (non-territorial) ST elevation with concave morphology distinguishes pericarditis from STEMI. Colchicine reduces recurrence by 50%. COPE, 2005
📋 Case 3, Low-Risk Chest Pain Safe Discharge
Patient: 38-year-old woman with no cardiac risk factors presents with left-sided sharp chest pain reproduced by palpation. No exertional component. Non-smoker, no family history of premature CAD.
Key findings: ECG: normal sinus rhythm, no ST changes. Troponin 0h: undetectable. Troponin 3h: undetectable. HEART score 1.
Management:
HEART score 0-3 with two negative high-sensitivity troponins = safe for discharge
Teaching point: HEART score 0-3 with 2 negative troponins at 0 and 3h has less than 1.6% risk of MACE at 30 days. This is one of the safest discharge criteria in emergency medicine. Reproducible chest wall tenderness makes musculoskeletal cause most likely.
📣 Sample Presentation
One-Liner
"Mr. Thompson is a 52-year-old smoker with HTN presenting with substernal chest pressure × 4 hours radiating to left jaw. Diaphoretic. ECG: normal sinus, no ST changes. Troponin 0.04 (pending repeat). HEART score 6."
Key Points to Cover on Rounds
High-risk chest pain -HEART score 6. DDx: ACS (high probability), must rule out PE, dissection, tamponade, tension PTX. ECG: no acute ST changes but doesn't rule out NSTEMI. Troponin 0.04 (borderline, repeat at 3h). Started ASA 325, heparin drip. Chest pain resolved with nitroglycerin SL × 2. CXR: no widened mediastinum (dissection less likely), no PTX. D-dimer not sent (low Wells for PE). Plan: serial troponin, if rising → cardiology for early cath. If negative × 2 → stress test before discharge PROMISE, 2015.
💊 Medications
Key Medications -Chest Pain / ACS Workup
Drug
Dose
Route
Indication
Notes
Aspirin STAT
325 mg chew STAT
PO (chew)
All suspected ACS
Chewing provides faster absorption than swallowing. Non-enteric coated. Give immediately -do not wait for troponin results.
Nitroglycerin
0.4 mg SL q5min x 3 doses
SL
Chest pain relief
Reduces preload → decreases myocardial O2 demand. Contraindicated if SBP < 90, RV infarct, PDE5 inhibitor within 24–48h (sildenafil/tadalafil).
Morphine
2–4 mg IV q5–15min PRN
IV
If NTG fails for pain
Use cautiously. May cause hypotension and respiratory depression. Some data suggests worse outcomes in NSTEMI -consider alternatives (fentanyl).
Heparin (UFH)
60 u/kg bolus (max 4000u) → 12 u/kg/hr
IV drip
High-suspicion ACS
Anticoagulation for suspected ACS. Target aPTT 60–80 sec. Alternative: enoxaparin 1 mg/kg SQ q12h.
Metoprolol
25 mg PO
PO
ACS if HR/BP allow
Beta-blocker -reduces myocardial O2 demand. Hold if: HR < 60, SBP < 100, signs of HF, PR > 0.24, 2nd/3rd degree AV block, active wheezing.
High-intensity statin
Atorvastatin 80 mg PO
PO
All ACS patients
Start immediately regardless of baseline LDL. Plaque stabilization. Continue lifelong.
MONA is OBSOLETE. The 2025 ACC/AHA ACS Guideline has significantly downgraded morphine, it delays absorption of P2Y12 inhibitors (ticagrelor, clopidogrel), reducing antiplatelet efficacy. CRUSADE registry data associated morphine with increased mortality in NSTEMI. Reserve morphine ONLY for pain refractory to nitroglycerin. Oxygen only if SpO2 < 90%, routine O2 in normoxemic MI showed no benefit and possible harm DETO2X-AMI, 2017.
⚡ Summary
Summary
ECG Within 10 Minutes
Before the labs, before triage is complete, before the history is finished.A STEMI diagnosis changes everything and door-to-balloon under 90 minutes saves myocardium.Repeat the ECG if the first is non-diagnostic and symptoms persist, since evolving infarction declares itself over minutes.
Rule Out the Five Killers First
Acute coronary syndrome, aortic dissection, pulmonary embolism, tension pneumothorax and esophageal rupture. Add cardiac tamponade. Most chest pain is benign, but the small fraction that is not will kill if missed, so the workup is structured as exclusion of the lethal causes rather than as a search for the likeliest one.
Let the Story Point You
Tearing pain radiating to the back with a blood pressure differential or a new AR murmur: dissection, get CT angiography.Pleuritic pain with dyspnea and hypoxia: pulmonary embolism.Sudden dyspnea with absent breath sounds and tracheal deviation: tension pneumothorax, decompress before imaging.Vomiting then severe pain with subcutaneous emphysema: esophageal rupture.
Use High-Sensitivity Troponin Properly
Serial draws with a 0/1 h or 0/3 h protocol are standard, and the delta matters more than the absolute value.A single very low hs-cTn draw can rule out MI in a suitable patient (HiSTORIC). A raised troponin is not automatically ACS: sepsis, pulmonary embolism, heart failure, myocarditis and renal disease all raise it, so a rise without a delta and without ischemic features is usually type 2.
HEART Is a Disposition Score
0 to 3 low risk (consider discharge), 4 to 6 moderate (admit), 7 to 10 high (early invasive).It answers who goes home from the emergency department, and it was never validated for choosing cath timing in an admitted NSTEMI, which is GRACE's job.
Discharge Against Explicit Criteria
HEART 0 to 3, negative serial troponins at least 3 h apart, a non-ischemic ECG, and resolution of symptoms.Arrange outpatient stress testing or cardiology follow-up within 72 h and give clear return precautions. Do not discharge on a single troponin and a normal ECG if the story is convincing.
Consider CCTA in the Right Patient
Low to intermediate risk with an unclear picture, where the very high negative predictive value can rule out coronary disease and end the workup. It also gives a calcium score. It is not the test for a high-probability patient, who needs invasive angiography rather than more imaging.
Do Not Be Reassured by the Wrong Things
A response to a GI cocktail does not exclude ACS, and neither does reproducible chest wall tenderness in a patient with a compelling story. Women, the elderly and diabetics present atypically, with dyspnea, fatigue or epigastric discomfort rather than crushing chest pain. Get a posterior and right-sided ECG when the picture fits but the standard leads look clean.
IgE-mediated systemic allergic reaction. Epinephrine is the ONLY first-line treatment -everything else is adjunctive. The most common mistake: giving diphenhydramine and steroids instead of epinephrine. Epi first, always.
🔍 Overview
Diagnostic Criteria -Any ONE of Three
Criterion 1: Acute onset (minutes–hours) of skin/mucosal involvement (hives, flushing, angioedema) PLUS respiratory compromise (dyspnea, stridor, wheeze, hypoxia) OR hypotension/end-organ dysfunction
Criterion 2: ≥ 2 of the following after exposure to LIKELY allergen: skin/mucosal symptoms, respiratory compromise, hypotension, persistent GI symptoms (cramping, vomiting)
Criterion 3: Hypotension alone after exposure to KNOWN allergen for that patient
Up to 20% of anaphylaxis has NO skin findings. Don't wait for hives to give epinephrine. Isolated hypotension or bronchospasm after allergen exposure = anaphylaxis.
Common Triggers
Foods: peanuts, tree nuts, shellfish, milk, eggs (#1 cause in children)
Medications: antibiotics (penicillin, cephalosporins), NSAIDs, contrast dye, anesthetic agents (#1 cause in perioperative setting)
Insect stings: Hymenoptera (bee, wasp, hornet) -#1 cause of fatal anaphylaxis in adults
Latex
Idiopathic (~20% -no identifiable trigger)
Biphasic Anaphylaxis
Up to 20% of anaphylaxis cases have a biphasic reaction -recurrence of symptoms 1–72 hours after initial resolution (most within 8–10h). This is why ALL patients require a minimum 4–6 hour observation period, and severe reactions warrant 12–24h observation. Steroids (methylprednisolone 125 mg IV) are given empirically to prevent biphasic reactions, though evidence is limited.
Clinical Example
Case
28F with known shrimp allergy presents from a restaurant with lip swelling, diffuse urticaria, audible wheezing, and BP 82/48 within 15 minutes of eating shellfish. HR 124, SpO₂ 91% on RA. This is anaphylaxis (Criterion 2: skin + respiratory + hypotension after known allergen).
🚨 Management
Treatment Protocol
EPINEPHRINE is the ONLY first-line treatment. There is NO contraindication to epinephrine in anaphylaxis -not age, not pregnancy, not cardiac disease. The risk of NOT giving epi is always greater than the risk of giving it.IM Epinephrine Pharmacokinetics Trial, 2004WAO, 2020
Step
Drug
Dose
Notes
1. EPINEPHRINE
Epinephrine 1:1000 (1 mg/mL) GIVE FIRST
0.3–0.5 mg IM (0.3–0.5 mL) in anterolateral thigh. Repeat q5–15 min if no improvement.
IM (not SubQ) -faster absorption IM Epinephrine Pharmacokinetics Trial, 2004. Anterolateral thigh (not deltoid) -better blood flow. Autoinjector: EpiPen 0.3 mg adult, 0.15 mg pediatric (< 30 kg). Most common error: not giving epi, giving it too late, or giving it SubQ.WAO Anaphylaxis Guidelines, 2020
2. Position
Supine with legs elevated (improves venous return). If vomiting → recovery position. If respiratory distress → sitting up. Do NOT have the patient stand or sit upright if hypotensive -can cause fatal "empty ventricle syndrome."
Diphenhydramine 50 mg IV + famotidine (Pepcid) 20 mg IV
H1 + H2 blockers
Adjunctive ONLY -do NOT give instead of epinephrine. Antihistamines treat hives but do NOT reverse bronchospasm or hypotension.
5. Steroids
Methylprednisolone 125 mg IV
Or dexamethasone 10 mg IV
Does NOT help acute anaphylaxis (takes 4–6h to work). May prevent biphasic reaction (occurs in ~5–20%, usually 1–72h later) Biphasic Anaphylaxis Review, 2015. Observe ≥ 4–6h after resolution.
Refractory
Epinephrine drip
1–10 mcg/min IV
If ≥ 2 doses of IM epi fail → start epi drip. Glucagon 1–5 mg IV if on beta-blockers (epi may be ineffective due to β-blockade). Vasopressin for refractory hypotension.
IM epinephrine is the ONLY life-saving treatment. Antihistamines and steroids are ADJUNCTS -they do NOT treat anaphylaxis. Delay in epinephrine = death.
NEVER give IV epinephrine push for anaphylaxis (unless cardiac arrest). IV push epi in a patient with a pulse causes fatal arrhythmias. Use IM or IV drip only.
Updated Practice: Old teaching: give IV Benadryl and steroids first, then epi if not improving. WRONG -epinephrine is FIRST, immediately. Every minute of delay increases mortality. WAO, 2020
🧪 Workup
Laboratory Workup
Tryptase level -draw within 1–2h of onset (peaks at 1h). Confirms mast cell degranulation. A normal tryptase does NOT rule out anaphylaxis.
CBC -baseline hematocrit, WBC
BMP -renal function, electrolytes (epinephrine can cause hypokalemia)
ECG -arrhythmias from epinephrine administration or myocardial involvement (Kounis syndrome -allergic MI)
Allergist referral -4–6 weeks post-event for skin-prick testing and component testing
Clinical diagnosis. Do NOT delay treatment waiting for labs. Tryptase is confirmatory, not diagnostic. If it looks like anaphylaxis, treat like anaphylaxis.
📋 On Rounds
Why give glucagon in anaphylaxis for patients on beta-blockers?
Epinephrine works primarily through β₁ (increased HR, contractility) and β₂ (bronchodilation, vasodilation in muscle) receptors. In patients on beta-blockers, these receptors are occupied/blocked → epinephrine is less effective → refractory anaphylaxis. Glucagon bypasses the β-receptor entirely -it activates adenylyl cyclase directly via the glucagon receptor → increases cAMP → positive inotropy + chronotropy + smooth muscle relaxation.
Why is IM epinephrine given in the anterolateral thigh and not the deltoid?
The anterolateral thigh (vastus lateralis) provides faster and higher peak epinephrine absorption than the deltoid, with peak plasma levels at ~8 minutes vs ~34 minutes for subcutaneous. This is because the thigh has rich vasculature and large muscle mass for IM absorption. Never give epi IV push for anaphylaxis (unless in cardiac arrest) -IV bolus can cause fatal arrhythmia. The dose is 0.3–0.5 mg of 1:1000 (1 mg/mL) IM, repeat q5–15 min.
A patient had an anaphylactic reaction 4 hours ago and feels fine. Can you discharge them?
Observe for biphasic reaction. Biphasic anaphylaxis occurs in 1-20% of cases (most estimates ~5%), typically 1-72 hours after the initial reaction (most within 8-10h). Risk factors for biphasic: severe initial reaction, delayed epinephrine, required > 1 dose of epi, unknown trigger. Minimum observation: 4-6 hours for mild reactions.
What are the diagnostic criteria for anaphylaxis?
Anaphylaxis is diagnosed when any 1 of 3 criteria is met: (1) Acute skin/mucosal involvement (hives, flushing, angioedema) + respiratory compromise (wheeze, stridor, hypoxia) OR hypotension. (2) ≥ 2 of the following after exposure to a likely allergen: skin/mucosal symptoms, respiratory compromise, hypotension, persistent GI symptoms (cramping, vomiting). (3) Hypotension alone after exposure to a known allergen for that patient.
Clinical Examples
📋 Case 1, Antibiotic-Induced Anaphylaxis
Patient: 42F, no known drug allergies. First dose IV piperacillin-tazobactam. Within 15 min: diffuse urticaria, lip swelling, wheeze, BP 72/38.
Epinephrine 0.5 mg IM anterolateral thigh (1:1000), FIRST, do not delay
Stop offending antibiotic immediately
NS 1-2L bolus; diphenhydramine 50 mg IV + famotidine 20 mg IV
Methylprednisolone 125 mg IV; albuterol neb for bronchospasm
Repeat epi q5-15 min if no improvement; epi drip if refractory
Teaching point: Most deaths from anaphylaxis result from delayed or withheld epinephrine. IM epinephrine has NO absolute contraindications. Antihistamines treat hives but do NOT reverse hypotension or airway obstruction. WAO, 2020
📋 Case 2, Refractory Anaphylaxis on Beta-Blockers
Patient: 67M, PMH CAD on metoprolol 100 mg BID. Bee sting 20 min ago. Flushing, tongue swelling, wheeze, BP 68/40, HR 52.
Key findings: Refractory hypotension despite 2 IM epi doses. HR blunted by beta-blocker.
Management:
Glucagon 1-5 mg IV bolus, then 5-15 mcg/min, bypasses beta-receptor
Epinephrine IV drip 1-10 mcg/min (ICU monitoring)
Aggressive IVF 2-3L; have suction ready (glucagon causes vomiting)
Teaching point: Beta-blockers blunt the cardiac response to epinephrine. Glucagon bypasses the beta-receptor via direct adenylyl cyclase activation, producing positive inotropy and chronotropy independent of beta-receptors.
Key findings: Biphasic anaphylaxis (~5% of cases, within 1-72h). Risk factors: severe initial reaction, > 1 epi dose needed, delayed treatment.
Management:
Repeat epinephrine 0.5 mg IM immediately
Admit for extended observation (12-24h minimum)
Continue H1 + H2 blockers and steroids
Discharge with EpiPen, allergist referral, action plan, medical alert bracelet
Teaching point: Biphasic reactions are why all anaphylaxis patients need minimum 4-6h observation (12-24h if severe). All patients need an EpiPen prescription and allergist referral at discharge.
📣 Sample Presentation
One-Liner
"Ms. Williams is a 35-year-old who developed diffuse urticaria, throat tightness, wheezing, and hypotension (BP 78/42) within 10 minutes of IV cefazolin administration. Consistent with anaphylaxis."
Key Points to Cover on Rounds
Anaphylaxis to cefazolin (probable cephalosporin allergy). Epinephrine 0.5 mg IM anterolateral thigh given × 1 → BP improved to 102/64. Additional: diphenhydramine 50 mg IV, famotidine 20 mg IV, methylprednisolone 125 mg IV, NS 1L bolus. Wheezing resolved with albuterol neb. Observed for biphasic reaction × 6 hours -no recurrence. Tryptase level drawn at 1h. Allergy documented: cephalosporins → anaphylaxis. EpiPen prescribed. Plan: allergist referral, avoid cephalosporins and high-cross-reactivity penilcillins, discharge with anaphylaxis action plan.
💊 Medications
Anaphylaxis Medications
Drug
Dose
Route
Role
Epinephrine (1:1000)
0.3–0.5 mg
IM anterolateral thigh
FIRST-LINE -repeat q5–15 min. No contraindications in anaphylaxis.
Diphenhydramine
50 mg
IV
H1 blocker -adjunct for urticaria/pruritus. Does NOT treat hypotension or bronchospasm.
Famotidine (Pepcid)
20 mg
IV
H2 blocker -adjunct. Combined H1+H2 blockade more effective than H1 alone.
Methylprednisolone
125 mg
IV
Prevents biphasic reaction (theoretical -weak evidence). Takes 4–6h to work. NOT for acute treatment.
Albuterol
2.5 mg neb
Nebulized
For bronchospasm refractory to epinephrine. Continuous neb if severe.
Glucagon
1–5 mg bolus, then 5–15 mcg/min
IV
For patients on beta-blockers. Bypasses β-receptor blockade → direct cAMP activation. Side effect: vomiting.
Epinephrine drip
1–10 mcg/min
IV infusion
Refractory anaphylaxis (failed ≥2 IM doses). ICU-level monitoring required.
⚡ Summary
Summary
Epinephrine Is the Only First-Line Treatment
0.3 to 0.5 mg IM of 1:1000 into the anterolateral thigh, repeated every 5 to 15 min as needed.Everything else is adjunctive.The commonest fatal mistake is giving diphenhydramine and steroids instead of epinephrine. Antihistamines treat hives; they do not treat airway edema, bronchospasm or shock.
There Is No Contraindication
Not age, not pregnancy, not coronary disease.The risk of withholding epinephrine always exceeds the risk of giving it, and delay is the strongest predictor of death in fatal anaphylaxis. Hesitating in an elderly cardiac patient is the exact situation in which the drug is most needed.
Never IV Push Epinephrine in a Patient With a Pulse
IV push causes fatal arrhythmia and hypertensive crisis.Use IM, and escalate to an IV infusion if IM doses fail, titrated under monitoring. IV push is reserved for cardiac arrest. This is one of the highest-consequence route errors in acute medicine.
Up to 20% Have No Skin Findings
Do not wait for hives.Isolated hypotension, or isolated bronchospasm, after exposure to a known or likely allergen is anaphylaxis and is treated as such. The diagnostic criteria are met by any one of three patterns, and only one of them requires skin or mucosal involvement.
Position and Resuscitate at the Same Time
Lay the patient flat with the legs elevated, unless they are vomiting or in respiratory distress.Sitting a hypotensive anaphylaxis patient up, or letting them stand, has caused sudden death from the empty ventricle syndrome.Give aggressive IV fluid, since massive capillary leak means these patients need liters, and remove the trigger where possible.
Know the Refractory Cases
Patients on beta blockers may not respond to epinephrine; give glucagon 1 to 5 mg IV, which bypasses the beta receptor to raise cyclic AMP. Add a vasopressor infusion for persistent hypotension, and prepare for a difficult airway early, since angioedema progresses fast and late intubation may be impossible.
Adjuncts Have a Role, Just Not the First One
H1 and H2 antihistamines for cutaneous symptoms, bronchodilators for bronchospasm, and steroids, historically given to prevent biphasic reactions though the evidence for that is weak. None of them substitutes for epinephrine, and none should delay it.
Observe, Then Prescribe and Refer
Biphasic reactions occur in up to 20%, typically within 4 to 12 h, so observe for 4 to 6 h, longer after severe reactions or repeated epinephrine doses. Discharge with two epinephrine autoinjectors, a demonstration of how to use them, and an anaphylaxis action plan, plus allergy referral. A serum tryptase drawn within 1 to 3 h can confirm the diagnosis retrospectively when the presentation was ambiguous.
Any rapid response or code blue -call BEFORE you go, even if you think you can handle it
New vasopressor requirement or escalation of existing pressors
Transfer to ICU or higher level of care
Acute stroke code -tPA window decisions
Acute MI / STEMI activation
Intubation needed (unless you're the person intubating)
New GI bleed with hemodynamic instability
Patient or family requesting to change code status urgently
Death -expected or unexpected (pronouncement, family notification, paperwork)
Any situation where you're unsure -calling too early is always better than calling too late
Cross-Cover Approach -Every Call
ABCDE for every page: Assess → Bedside (go see the patient) → Chart review → Decide → Execute + follow-up
Step 1 -Get the right information from the nurse: Vitals (current + trend), mental status change, what intervention was already tried, code status, is the primary team aware?
Step 2 -Go see the patient: Never manage cross-cover issues by phone alone. A 30-second bedside assessment (airway, breathing, circulation, mental status) tells you more than 10 minutes of chart review.
Step 3 -Check the chart: Admitting diagnosis, active problems, recent labs/imaging, medications (what changed today?), code status, allergies.
Step 4 -Address the acute issue: Order what's needed (stat labs, imaging, meds). Don't shotgun -think about what will change your management.
Step 5 -Document: Brief cross-cover note -what you were called for, what you found, what you did, and follow-up plan. The primary team needs to know what happened overnight.
Common Overnight PRN Orders
Problem
First-Line Order
Notes
Insomnia
Melatonin 3-5 mg PO
NOT diphenhydramine in elderly (delirium, falls). Trazodone 25-50 mg alternative.
Pain (mild)
Acetaminophen 650 mg PO q6h
Max 3g/day if liver disease. Scheduled > PRN for consistent control.
Pain (moderate)
Oxycodone 5 mg PO q4h PRN
Start low in opioid-naive. Add PEG 3350 + senna. Check last dose timing.
Nausea
Ondansetron 4 mg IV/PO q6h
Check QTc first. Promethazine is more sedating. Avoid metoclopramide if Parkinson's.
Constipation
PEG 3350 17g daily + senna 2 tabs PO QHS
If on opioids: must have a bowel regimen. Bisacodyl 10 mg PR if > 3 days. Do not use docusate (ineffective).
Agitation
Non-pharm first. If severe: haloperidol 0.5-2 mg IV/IM
UA + CXR. Don't reflexively add antibiotics without evaluating -call senior if sepsis concern.
Hypertension (asymptomatic)
Restart home meds if held. PRN: hydralazine 10 mg IV or labetalol 10 mg IV
Don't treat numbers -treat end-organ damage. Asymptomatic BP 180/100 can often wait until morning.
Hypoglycemia (glucose < 70)
D50 25 mL IV push (if NPO/altered) or juice + crackers (if eating)
Recheck in 15 min. Identify cause: excess insulin? missed meal? Hold offending agent.
Foley issues
Flush with 30 mL NS. If blocked → replace.
If can't place → call urology for difficult catheterization. Don't force it.
Night Float Tips from Senior Residents
Read sign-out BEFORE your shift starts. Know your "watchers" -the patients most likely to decompensate. See them first.
Pre-round on the sickest patients at the start of your shift, not when they're crashing at 3 AM.
Keep a running list of what happened overnight. Sign out in the morning should be efficient -"here's what happened, here's what I did, here's what needs follow-up."
Eat before your shift, bring snacks, and have caffeine strategically (not at 4 AM if you want to sleep post-call).
Batch your work: if you're going to one floor to see a patient, check if there are other pages on the same floor.
The patient is not your enemy at 3 AM. They're scared, in pain, and in an unfamiliar place. A 30-second reassuring visit can prevent 5 more pages.
If you're drowning, tell someone. Call your senior. Page the attending if needed. Patient safety > pride.
Classify by MCV first -microcytic, normocytic, or macrocytic. Then use iron studies, reticulocyte count, and peripheral smear to narrow the diagnosis. Iron deficiency is the most common cause worldwide.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 MCV-Based Classification
MCV
Category
Differential
Key Labs
< 80
Microcytic
Iron deficiency (#1 -GI blood loss in men/postmenopausal women until proven otherwise), thalassemia (Mentzer index: MCV/RBC < 13 → thalassemia, > 13 → iron def), anemia of chronic disease (some), sideroblastic, lead poisoning
Iron studies, ferritin, TIBC, reticulocyte count, Hgb electrophoresis if thalassemia suspected
B12, folate, reticulocyte count, TSH, peripheral smear (hypersegmented neutrophils → megaloblastic), methylmalonic acid (↑ in B12 def, normal in folate def)
New iron deficiency anemia in a man or postmenopausal woman = GI malignancy until proven otherwise. These patients need colonoscopy + upper endoscopy. Do NOT just give iron and move on.
Reticulocyte Count -Production vs Destruction
Reticulocyte count > 2% (or reticulocyte index > 2): bone marrow is responding → the problem is blood loss or destruction (hemolysis)
Reticulocyte count < 2%: bone marrow is NOT responding → underproduction (iron/B12/folate deficiency, CKD, bone marrow failure, anemia of chronic disease)
Reticulocyte Production Index (RPI): (retic % × Hgb/15) / maturation factor. RPI > 2 = appropriate response.
🧪 Iron Studies Interpretation
Lab
Iron Deficiency
Anemia of Chronic Disease
Both (Mixed)
Serum iron
↓
↓
↓
Ferritin
↓↓ (< 30)
↑ or normal (acute phase reactant)
Low-normal (30–100)
TIBC
↑ (body wants more iron)
↓ (body not trying to absorb more)
Variable
Transferrin saturation (TSAT)
↓ (< 20%)
↓ (15–20%)
↓
Ferritin is an acute phase reactant -it rises with inflammation, infection, liver disease, and malignancy. A "normal" ferritin of 50–100 in an inflamed hospitalized patient may actually represent iron deficiency. Ferritin < 30 is diagnostic of iron deficiency. Ferritin < 100 in the setting of inflammation is suggestive.
What is TSAT (Transferrin Saturation)? The percentage of transferrin (the iron-carrying transport protein) that is currently bound to iron. Formula: TSAT = (serum iron ÷ TIBC) × 100. Normal range: 20-50%. Iron deficiency: < 20%. Iron overload: > 45-50% (consider hemochromatosis or transfusion overload).
Why it complements ferritin: TSAT reflects the iron actually available right now for erythropoiesis (the "circulating" iron pool), while ferritin reflects storage iron. TSAT is less affected by inflammation, so it's the more reliable marker when ferritin is unreliable -hospitalized inflamed patients, HF, CKD, chronic infection, malignancy. A patient with ferritin 80 + TSAT 12% is iron-deficient even though the ferritin looks "OK."
Pre-test pearls: hold oral iron for 24-48 h before drawing labs (recent iron pill falsely elevates TSAT). TSAT has a diurnal rhythm -higher in the morning -so a fasting AM draw is most reliable when the result is borderline.
Iron Replacement
Route
Agent
Notes
Oral
Ferrous sulfate 325 mg PO daily–TID
Take on empty stomach with vitamin C (enhances absorption). GI side effects are dose-limiting. Every-other-day dosing may improve absorption and tolerability. Takes 3–6 months to replete stores.
IV (preferred if)
Iron sucrose (Venofer) 200 mg IV × 5 doses or ferric carboxymaltose (Injectafer) 750 mg IV × 2
Preferred if: oral intolerant, CKD/dialysis, IBD, ongoing blood loss exceeding oral repletion, Hgb < 7 with symptoms, pre-surgery. Injectafer: can give 750 mg in one sitting (fewer visits).
🧪 Workup
Workup
CBC + retic count (#1 test)
Peripheral smear
Iron studies
B12 + folate
LDH, haptoglobin, indirect bili -hemolysis
Direct Coombs
EPO level
Bone marrow biopsy if unclear
🚨 Management
Management
Iron deficiency: FIND SOURCE + IV iron (ferric carboxymaltose 750mg×2) or PO. Transfuse: Hgb<7 in most patients TRICC, Hébert 1999
B12: IM cyanocobalamin 1000mcg daily×7→weekly×4→monthly
How do you distinguish iron deficiency from anemia of chronic disease when both have low serum iron?
Ferritin and TIBC. In iron deficiency, the body is truly depleted of iron → ferritin is low (< 30) and TIBC is high (the body upregulates transferrin to grab any available iron). In anemia of chronic disease, iron is trapped in macrophages by hepcidin (the inflammatory "iron warden") → ferritin is normal or high (iron is stored, just not released) and TIBC is low (no need to absorb more -there's plenty, just sequestered).
A patient has a ferritin of 80 but you still suspect iron deficiency. How is that possible?
Ferritin is an acute phase reactant -it rises with inflammation, infection, liver disease, and malignancy regardless of iron stores. A 'normal' ferritin of 80 in a patient with active inflammation (elevated CRP) may actually represent iron deficiency. In the setting of chronic disease or inflammation, a ferritin < 100 with transferrin saturation < 20% suggests functional iron deficiency even though ferritin appears 'normal'.
A patient has pancytopenia. What's your differential and what do you order?
Pancytopenia = all three lines down (anemia + leukopenia + thrombocytopenia). Differential by mechanism: Decreased production (bone marrow failure): aplastic anemia, MDS, leukemia/lymphoma, myelofibrosis, B12/folate deficiency (megaloblastic), drug-induced (methotrexate, chemotherapy), infections (HIV, hepatitis, parvovirus, TB). Increased destruction: hypersplenism (cirrhosis), DIC, TTP/HUS, autoimmune (SLE). Workup: CBC with peripheral smear (blasts → leukemia; schistocytes → TTP/DIC; hypersegmented neutrophils → B12/folate; teardrop cells → myelofibrosis). Reticulocyte count (↓ = production problem, ↑ = destruction/loss). B12, folate, LDH, haptoglobin, Coombs. HIV, hepatitis serologies. Fibrinogen, D-dimer, PT/PTT if DIC suspected. ADAMTS13 if TTP suspected. SPEP/free light chains if myeloma on smear (rouleaux). Bone marrow biopsy if etiology unclear after initial labs, or if blasts / leukoerythroblastic picture on smear.
How do you approach anemia when the MCV is normal (normocytic)?
Normocytic anemia (MCV 80-100): the broadest differential. Step 1: Reticulocyte count.High retic (> 2%): the marrow is responding → blood LOSS or blood DESTRUCTION. Check: LDH, haptoglobin, Coombs test. If hemolysis markers positive → hemolytic anemia (autoimmune, TTP, DIC, G6PD, sickle cell, PNH). If hemolysis markers negative → acute blood loss (look for the source). Low retic (< 2%): marrow is NOT responding → production problem.
Clinical Examples
📋 Case 1, Microcytic Anemia from Menorrhagia
Patient: 34-year-old premenopausal woman with heavy menstrual periods presents with fatigue and pica (ice craving).
Warm AIHA secondary to SLE: prednisone 1 mg/kg/day
Transfuse if hemodynamically unstable
If steroid-refractory: rituximab or splenectomy
Teaching point: Warm AIHA (IgG-mediated) is associated with SLE, CLL, and drugs. MCV may be falsely elevated because reticulocytes are larger than mature RBCs. Haptoglobin is the most sensitive hemolysis marker.
📋 Case 3, Macrocytic Anemia from B12 Deficiency
Patient: 68-year-old vegan woman presents with fatigue, glossitis, and bilateral lower extremity paresthesias. Decreased vibration sense, positive Romberg.
Key findings: Hgb 9.2, MCV 124, reticulocyte index 0.6. B12 less than 100. Methylmalonic acid 2400 (markedly elevated). Smear: macro-ovalocytes, hypersegmented neutrophils.
Management:
IM cyanocobalamin 1000 mcg daily x 7d, then weekly x 4, then monthly lifelong
Monitor K+ and phosphate (drop during rapid erythropoiesis)
Neurology follow-up for subacute combined degeneration
Teaching point: B12 deficiency causes subacute combined degeneration (posterior columns + lateral corticospinal tracts). Methylmalonic acid differentiates B12 from folate deficiency. Neurologic damage may be irreversible if treatment is delayed.
📣 Sample Presentation
One-Liner
"Mrs. Rivera is a 48-year-old premenopausal woman with fatigue and Hgb 8.2, MCV 72. Iron studies: ferritin 8, TIBC 450, transferrin sat 6%. Consistent with iron deficiency anemia."
Key Points to Cover on Rounds
Microcytic anemia -iron deficiency confirmed (ferritin 8, Tsat 6%). Source: heavy menstrual bleeding (menorrhagia × 2 years, soaking through pads). No GI symptoms, no melena. Given her age and clear gynecologic source, GI workup deferred. Treatment: IV iron infusion (ferric carboxymaltose 750 mg × 2 doses, 1 week apart) -chose IV over PO due to severity and faster repletion. Gynecology referral for menorrhagia management. Plan: recheck CBC + ferritin in 6-8 weeks, expect Hgb rise 1 g/dL per week of iron.
💊 Medications
Key Medications -Anemia
Treatment depends on the cause. Iron deficiency = replace iron + find source. B12 deficiency = replace B12. Anemia of CKD = iron first, then ESA. Hemolytic = treat underlying cause.
Drug
Dose
Route
Indication
Ferrous sulfate
325 mg PO daily–TID
PO
Iron deficiency anemia (mild-moderate). Take on empty stomach with vitamin C. Every-other-day dosing may improve absorption.
Iron sucrose (Venofer)
200 mg IV x 5 doses
IV
IV iron preferred if: oral intolerant, CKD/dialysis, IBD, Hgb < 7, ongoing blood loss, pre-surgery.
Ferric carboxymaltose (Injectafer)
750 mg IV x 2 (1 week apart)
IV
Convenient IV iron -can give 750 mg in one sitting (fewer visits).
Cyanocobalamin (B12)
1000 mcg IM daily x 7d → weekly x 4 → monthly
IM
B12 deficiency. High-dose oral (1000–2000 mcg/day) may be adequate if no absorption issues.
Folic acid
1 mg PO daily
PO
Folate deficiency. Always check B12 first -folate alone can mask B12 deficiency (corrects anemia but NOT neuro damage).
Epoetin alfa (Procrit)
50–300 units/kg 3x/week
IV/SQ
Anemia of CKD (after iron repletion). Target Hgb 10–11.5. Never > 13.
Hgb < 7 for most patients [TRICC, TRISS]. Hgb < 8 for active cardiac ischemia. Never transfuse to a number -transfuse for symptoms.
B12 Deficiency
Can cause pancytopenia mimicking leukemia. Hypersegmented neutrophils on smear. Neuro symptoms (subacute combined degeneration). Check methylmalonic acid.
Reticulocyte Count
The single most important test. High retic = bone marrow is working (loss or destruction). Low retic = production failure (check iron/B12/folate, consider biopsy).
Ferritin < 30 (or < 100 in inflammation/CKD), low transferrin sat. FIND THE SOURCE: GI (colonoscopy if > 50 or alarm features), menstrual, malabsorption. IV iron for severe or refractory.
The most overdiagnosed infection in medicine -up to 30% of "cellulitis" admissions are actually stasis dermatitis, DVT, gout, or contact dermatitis. Purulent vs non-purulent determines whether you cover MRSA. Mark the borders with a pen.
🔍 Overview
Purulent vs Non-Purulent -This Drives Treatment
Type
Features
Organism
Treatment
Non-purulent cellulitis
Diffuse erythema, warmth, tenderness. No abscess, no pus, no drainage. Clear borders.
Beta-hemolytic strep (Group A strep) is the most common cause. NOT usually MRSA.
Cefazolin (Ancef) 2g IV q8h (inpatient) or cephalexin 500 mg QID (outpatient). 5–6 days is sufficientIDSA, 2014. No MRSA coverage needed.
Purulent cellulitis / abscess
Fluctuant, drainable collection. Pus expressed. Central pustule or wound.
S. aureus (MSSA or MRSA) -especially CA-MRSA (USA300).
I&D is the primary treatment (antibiotics alone are less effective). Talan et al. (NEJM), 2016 Antibiotics: TMP-SMX (Bactrim) DS BID or doxycycline (Vibramycin) 100 mg BID × 5–7 days. IV: vancomycin if severe.
Necrotizing fasciitis SURGICAL EMERGENCY
Pain out of proportion, crepitus, rapid spread, bullae, skin necrosis, hemodynamic instability. LRINEC score ≥ 6 → high suspicion.
Type I: polymicrobial. Type II: Group A strep (monomicrobial).
Emergent surgical debridement (do NOT wait for imaging). Vanc + pip-tazo + clindamycin (clindamycin inhibits toxin production). ICU.
Cellulitis mimics (up to 30% of admissions): stasis dermatitis (bilateral, chronic, hemosiderin staining -#1 mimic), DVT (unilateral leg swelling → get duplex US), gout (peri-articular), contact dermatitis, erythema migrans (Lyme -single expanding ring), lipodermatosclerosis (woody induration).
Key Principles
Mark the borders with a pen and date/time it -this is how you track whether it's improving or spreading on antibiotics
Blood cultures are NOT recommended for uncomplicated cellulitis (positive in < 2%). IDSA SSTI Guidelines, 2014 Only get if: sepsis, immunocompromised, animal/water bite, or unusual exposures.
Elevate the affected limb -reduces edema and speeds resolution
Bilateral "cellulitis" is almost never cellulitis -think stasis dermatitis, HF, venous insufficiency
Not improving at 48–72h? Consider: wrong diagnosis (mimic), abscess needing drainage, resistant organism, deeper infection (osteomyelitis, septic joint), necrotizing fasciitis
🧪 Workup
Workup -Cellulitis & Skin Infections
CBC with differential -leukocytosis supports infection, but WBC is often normal in uncomplicated cellulitis. Bandemia or left shift suggests more severe/systemic infection.
Blood cultures -only if systemic signs/sepsis (fever > 38.5°C, tachycardia, hypotension, immunocompromised). NOT routine for simple cellulitis -yield is < 2% IDSA, 2014Perl et al., 1999
Wound culture -only if abscess drained (send purulent material) or open wound present. Swab of intact skin over cellulitis is useless -do not send.
Ultrasound -if abscess suspected but not clinically obvious. Bedside US has excellent sensitivity for detecting drainable fluid collections. A missed abscess is the #1 reason cellulitis "fails" antibiotics.
Mark borders with skin marker -draw along the leading edge of erythema and write the date/time. This is the most important bedside tool to objectively track response at 48h.
Cellulitis is a clinical diagnosis. Imaging is for ruling out abscess (US) or necrotizing fasciitis (CT with gas), NOT for confirming cellulitis. If bilateral → think stasis dermatitis. If unilateral with edema → consider DVT (get duplex US). Up to 30% of "cellulitis" admissions are misdiagnosed.
🔄 Updated Practice: Old teaching: draw blood cultures for all cellulitis. Current practice: blood cultures are positive in <2-5% of uncomplicated cellulitis and do not change management. Only draw blood cultures if: systemic signs of sepsis (fever, tachycardia, hypotension), immunocompromised, facial cellulitis, animal/water exposure, or failed outpatient therapy (IDSA 2014). Similarly, wound cultures are only useful from abscess drainage or open wounds, surface swabs grow contaminants.
🚨 Management
Management by Severity
Severity
Treatment
Duration
Key Points
Mild (outpatient) Non-purulent, no systemic signs
Cephalexin (Keflex) 500 mg PO QID
5–7 days Hepburn et al., 2004
Covers Group A strep. No MRSA coverage needed. Elevate limb, mark borders, follow-up in 48h.
Moderate (inpatient) Systemic signs, rapid spread, failed PO
I&D primary + TMP-SMX DS PO BID or doxycycline 100 mg PO BID
5–7 days
I&D is the definitive treatment, antibiotics alone are inferior. Daum et al. (NEJM), 2017 Send wound culture. Pack wound, recheck in 48h.
Severe / Necrotizing Fasciitis SURGICAL EMERGENCY
Vancomycin + pip-tazo 4.5g IV q6h + clindamycin 900 mg IV q8h
Until surgical debridement + clinical improvement
Pain out of proportion, crepitus, bullae, rapid spread → call surgery immediately. Clindamycin inhibits toxin production. Do NOT delay for imaging.
IV → PO Transition Criteria
Afebrile × 24 hours
WBC trending down
Erythema receding past marked borders (the most objective criterion)
Tolerating oral intake
Systemically well (no ongoing tachycardia, hypotension)
Transition typically at 48–72h. Switch cefazolin IV → cephalexin PO. Total antibiotic course: 5–7 days (including IV days). Longer courses (10–14 days) only for immunocompromised or slow response. Eron et al., 2003
Recurrence Prevention
Treat tinea pedis (interdigital cracking is the #1 portal of entry), topical terbinafine × 2–4 weeks
Compression stockings for chronic venous insufficiency and lymphedema
Skin care, moisturize dry skin, avoid trauma, treat eczema and dermatitis
Weight loss, obesity and lymphedema are major risk factors for recurrence
Prophylactic antibiotics, consider penicillin V 250 mg PO BID for ≥ 3 episodes/year PATCH I, 2013
📋 On Rounds
Why is non-purulent cellulitis usually strep and not staph?
Non-purulent (diffuse) cellulitis is caused by bacteria that spread through tissue planes via hyaluronidase and streptokinase -enzymes that break down connective tissue and dissolve clots, allowing rapid lateral spread. Beta-hemolytic streptococci (especially Group A) excel at this. S. aureus, by contrast, tends to form localized, walled-off collections (abscesses) because it produces coagulase (promotes clot formation around the infection).
How do you distinguish cellulitis from DVT, and why does it matter?
Both present with a red, swollen, warm leg -and misdiagnosis is common. Key distinguishers: Cellulitis = fever, leukocytosis, skin warmth with clear border, often portal of entry (wound, tinea pedis), bilateral involvement suggests stasis dermatitis not cellulitis. DVT = unilateral leg edema, calf tenderness on palpation, risk factors (immobility, cancer, surgery), usually no fever or skin erythema early on.
How do you decide between IV and PO antibiotics for cellulitis?
Outpatient PO: Non-purulent, no systemic toxicity (afebrile, non-toxic), small area, immunocompetent, reliable follow-up. Drug: cephalexin 500 mg QID × 5-7 days. Inpatient IV: Rapidly spreading (beyond marked borders), systemic toxicity (fever, tachycardia, WBC > 15K), failed outpatient PO after 48h, immunocompromised, facial cellulitis, periorbital cellulitis, hand cellulitis, concern for deeper infection. Drug: cefazolin 2g IV q8h.
What are the red flags that suggest necrotizing fasciitis instead of simple cellulitis?
Nec fasc mimics cellulitis early but kills fast. Red flags: (1) Pain out of proportion to exam (the hallmark, disproportionate pain = alarm), (2) Rapid progression (spreading beyond marked borders within hours, not days), (3) Systemic toxicity (high fever, tachycardia, hypotension out of proportion to skin findings), (4) Crepitus (gas in tissues, palpable or visible on imaging), (5) Hemorrhagic bullae or skin necrosis (dusky, purple discoloration = fascial ischemia), (6) Lab flags (WBC > 25K, Na < 135, Cr elevated, CRP > 150, calculate LRINEC score ≥ 6). Call surgery immediately, do NOT delay for imaging. Negative CT does not rule it out.
A patient with a skin abscess asks if antibiotics alone can treat it. What do you tell them?
Incision and drainage (I&D) is the primary treatment for cutaneous abscesses. The LOOP trial and a landmark NEJM trial by Rajendran et al. (2017) confirmed that I&D alone cures most uncomplicated abscesses. Adding TMP-SMX or clindamycin after I&D modestly improves cure rates (~7% absolute benefit) per the IDSA 2014 guidelines, but antibiotics WITHOUT drainage have unacceptably high failure rates. Talan et al., 2016
Why do you mark the borders of cellulitis with a skin marker?
Marking the leading edge of erythema with date/time is the most objective way to assess treatment response at 48h. Cellulitis erythema that remains within or recedes past the marks = responding. Spreading beyond marks = failing therapy. Without marks, subtle progression or improvement is impossible to detect, especially with shift changes. This simple bedside tool prevents unnecessary antibiotic escalation and catches true treatment failures early.
What is the most common cause of recurrent lower extremity cellulitis and how do you prevent it?
Tinea pedis (athlete's foot) with interdigital cracking is the #1 portal of entry for recurrent leg cellulitis. Other risk factors: lymphedema, chronic venous insufficiency, obesity, prior cellulitis. Prevention: treat tinea pedis (topical terbinafine x 2-4 weeks), moisturize dry skin, compression stockings for edema, weight loss. For >= 3 episodes/year, consider prophylactic penicillin V 250 mg BID. PATCH I, 2013PATCH II, 2020
When should you suspect necrotizing fasciitis and what is the LRINEC score?
Suspect nec fasc when pain is OUT OF PROPORTION to skin findings, rapid spread, crepitus, hemorrhagic bullae, skin necrosis, or hemodynamic instability. LRINEC score uses 6 labs: CRP (>150 = 4 pts), WBC (>15k = 1, >25k = 2), Hgb (<11 = 2, <13.5 = 1), Na (<135 = 2), Cr (>1.6 = 2), glucose (>180 = 1). Score >= 6 = high suspicion. BUT a low score does NOT rule it out. Clinical suspicion trumps any score. Call surgery immediately - do NOT wait for imaging. Wong et al., 2004
A patient's cellulitis is not improving after 48 hours of cefazolin. What is your differential?
Five things to consider: (1) Wrong diagnosis - stasis dermatitis, DVT, gout, contact dermatitis (up to 30% of cellulitis admissions are misdiagnosed). (2) Missed abscess - get bedside ultrasound (a missed drainable collection is the #1 reason cellulitis 'fails'). (3) Resistant organism - broaden to vancomycin for MRSA coverage. (4) Deeper infection - osteomyelitis, septic joint, pyomyositis (get MRI). (5) Necrotizing fasciitis - pain out of proportion, crepitus, rapid spread = emergent surgery.
Case 1: Non-Purulent Cellulitis
Presentation: 58M with HTN and chronic venous insufficiency presents with 2 days of progressive left lower leg redness, warmth, and pain. He noticed a small crack between his toes (tinea pedis) last week. Exam shows well-demarcated unilateral erythema from mid-shin to ankle, warmth, tenderness, no fluctuance or crepitus. No purulence or drainable collection. T 38.2°C, HR 88, BP 142/86. WBC 13.2.
Key Actions:
• Draw borders with skin marker and document date/time for 48h reassessment
• Start cefazolin (Ancef) 2g IV q8h, no MRSA coverage needed for non-purulent cellulitis
• Elevate the affected limb above heart level to reduce edema
• Rule out DVT with duplex ultrasound if significant unilateral swelling or risk factors
• Transition to cephalexin (Keflex) 500 mg PO QID once afebrile × 24h, WBC trending down, and erythema receding past marked borders
• Treat underlying tinea pedis with topical antifungals to eliminate portal of entry and prevent recurrence
• Total antibiotic course: 5–7 days
Case 2: Purulent MRSA Abscess
Presentation: 28F, otherwise healthy, presents with 4 days of a painful, enlarging left axillary lump with overlying redness. She shaves her axillae regularly. Exam shows a 3 cm fluctuant, tender, erythematous mass with a central area of pointing. No surrounding induration or tracking lymphangitis. Afebrile, vitals stable, WBC 9.8. No systemic signs of infection.
Key Actions:
• I&D is the primary treatment, antibiotics alone are inferior for drainable abscesses
• Send wound culture from purulent material (not a surface swab) to confirm MRSA and guide therapy
• Start TMP-SMX (Bactrim) DS 1 tab PO BID × 7 days or doxycycline (Vibramycin) 100 mg PO BID × 7 days for MRSA coverage
• No IV antibiotics needed, patient is non-toxic, afebrile, and abscess is well-localized
• Pack wound loosely with iodoform gauze, arrange follow-up in 48h for repacking and wound check
• Educate on wound care: keep clean, avoid shaving the area until healed, no sharing towels or razors
Case 3: Necrotizing Fasciitis Concern
Presentation: 65M with poorly controlled diabetes (A1c 10.2) and PVD presents with 1 day of rapidly worsening right lower leg pain, erythema, and swelling. Exam shows dusky erythema extending from foot to knee with hemorrhagic bullae, crepitus on palpation, and pain dramatically out of proportion to visible skin findings. T 39.4°C, HR 122, BP 88/52, WBC 22.1, lactate 3.8, Cr 1.9.
Key Actions:
• Emergent surgical consult, do NOT delay for imaging. Necrotizing fasciitis is a clinical and surgical diagnosis
• Calculate LRINEC score (WBC, Hgb, Na, glucose, Cr, CRP), score ≥ 6 is highly suspicious
• Start broad-spectrum empiric coverage immediately: vancomycin (Vancocin) 25 mg/kg IV + piperacillin-tazobactam (Zosyn) 4.5g IV q6h + clindamycin (Cleocin) 900 mg IV q8h
• Clindamycin is added specifically to inhibit toxin production (protein synthesis inhibitor), critical in GAS necrotizing fasciitis
• Aggressive IV fluid resuscitation, vasopressors if needed, ICU admission
• CT may show fascial gas but a negative CT does NOT rule out nec fasc, surgery decides
• Mortality 20–40% even with optimal care; delay in debridement is the strongest predictor of death
📣 Sample Presentation
One-Liner
"Mr. Williams is a 56-year-old diabetic presenting with left lower leg erythema, warmth, and swelling × 3 days. No abscess or purulence. Tinea pedis noted on foot exam. Non-purulent cellulitis."
Key Points to Cover on Rounds
Non-purulent cellulitis -likely strep (Group A). Portal of entry: tinea pedis (interdigital cracking). Borders marked with skin marker + time. Treatment: cefazolin 2g IV q8h (first-line for non-purulent). No I&D needed (no abscess on exam, no fluctuance). US: no fluid collection. Blood cultures not sent (low yield unless septic/immunocompromised). Leg elevated. Response at 48h: erythema receding from marked borders. Plan: transition to cephalexin 500 QID PO to complete 5-7 day course. Treat tinea pedis (terbinafine cream) to prevent recurrence.
Mark and remeasure daily (at least q12h if concern for rapid spread)
Erythema receding past marked borders = responding. Spreading beyond marks at 48h → broaden antibiotics, image for abscess, or consider necrotizing fasciitis.
WBC
Daily while on IV antibiotics
Trending down = responding. Rising or persistently elevated → consider treatment failure, abscess, deeper infection, or wrong diagnosis.
Fever curve
q4h (Tmax documented daily)
Afebrile × 24h is one criterion for IV → PO transition. Persistent fever > 48h on appropriate antibiotics → re-evaluate diagnosis and coverage.
IV → PO transition criteria
Assess daily starting at 48h
Transition to oral when: afebrile × 24h, WBC trending down, erythema receding past marked borders, tolerating PO, systemically well. Usually at 48–72h.
Wound check (if I&D performed)
Daily until packing removed
Wound packing removed or changed at 48h. Assess for re-accumulation, ongoing drainage, surrounding cellulitis. Consider wound culture if not improving.
Not improving at 48h? Differential: (1) missed abscess (get US), (2) wrong diagnosis (stasis dermatitis, DVT, gout), (3) resistant organism (broaden to vancomycin), (4) deeper infection (osteomyelitis, septic joint → MRI), (5) necrotizing fasciitis (pain out of proportion, crepitus, rapid spread → emergent surgery).
Covers beta-hemolytic strep (Group A). No MRSA coverage needed. Shorter courses (5 days) are effective IDSA, 2014.
Non-purulent cellulitis (inpatient) 1ST LINE
Cefazolin (Ancef)
2g IV q8h
Transition to cephalexin PO when afebrile × 24h, WBC trending down, erythema receding past marked borders.
Purulent / abscess (MRSA coverage)
TMP-SMX (Bactrim) DS or Doxycycline (Vibramycin)
TMP-SMX DS 1 tab PO BID × 5–7 days Doxycycline 100 mg PO BID × 5–7 days
I&D is the primary treatment for abscess -antibiotics are adjunctive. Both cover CA-MRSA. TMP-SMX: avoid in pregnancy, check K⁺ (can cause hyperkalemia). Doxycycline: photosensitivity, avoid in pregnancy.
Vanc: 15–20 mg/kg IV q8–12h (target AUC/MIC 400–600) Pip-tazo: 4.5g IV q6h Clindamycin: 900 mg IV q8h
Clindamycin inhibits toxin production (ribosomal suppression) -critical for toxin-mediated disease (GAS, S. aureus). Broad coverage for polymicrobial (Type I) and monomicrobial (Type II) nec fasc. Emergent surgical debridement is definitive treatment.
PCN allergy? Non-purulent: clindamycin 300–450 mg PO TID (but 15–20% MRSA resistance in some areas). Severe: vancomycin alone covers both MRSA and most strep. For true anaphylaxis to penicillin, avoid all cephalosporins (although cross-reactivity is < 2% with cephalexin).
⚡ Summary
Summary
Purulent or Non-Purulent Drives Everything
Purulent (abscess, furuncle, carbuncle): S. aureus including MRSA, so cover MRSA and, above all, drain it.Non-purulent (diffuse cellulitis, erysipelas): beta-hemolytic streptococci, so cover streptococci with cefazolin or cephalexin and do not routinely add MRSA cover.Reflexively adding vancomycin to every cellulitis is over-treatment that adds toxicity without improving cure.
Incision and Drainage Is the Treatment for an Abscess
Antibiotics alone do not cure a walled-off collection.Drain it, and add antibiotics for a larger abscess, surrounding cellulitis, systemic symptoms, immunosuppression or failure of drainage alone. Ultrasound is useful when it is unclear whether there is a drainable collection.
Up to 30% of Admissions Are Not Cellulitis
Stasis dermatitis is the commonest mimic: bilateral, chronic, with hemosiderin staining. Bilateral means it is almost certainly not cellulitis, which is nearly always unilateral. Also consider DVT (get a duplex), gout, contact dermatitis, erythema migrans and lipodermatosclerosis. Misdiagnosis means unnecessary antibiotics and a missed real diagnosis.
Do Not Draw Routine Blood Cultures
They are positive in under 2 to 5% of uncomplicated cellulitis and do not change management.Draw them only for systemic toxicity, immunosuppression, neutropenia, animal or water exposure, or suspected necrotizing infection. Cellulitis is a clinical diagnosis, and imaging is for excluding abscess or necrotizing fasciitis, not for confirming it.
Switch to Oral at 48 to 72 Hours
Cefazolin IV to cephalexin PO once fever has settled and the erythema has stopped advancing.Total course 5 to 7 days including the IV days; longer courses of 10 to 14 days only for the immunocompromised or a slow response. Erythema often looks worse in the first 24 to 48 h as bacterial killing releases inflammatory mediators, so that alone is not treatment failure.
Mark the Border and Elevate
Draw the margin with a pen and date it. It is the simplest objective measure of response and it settles the daily argument about whether the cellulitis is improving. Elevate the limb, which reduces edema and speeds resolution more than any adjunctive drug.
Exclude Necrotizing Infection Deliberately
Pain out of proportion to the exam, rapid progression, systemic toxicity, bullae, crepitus or skin anesthesia means surgical consultation now.Do not wait for imaging: CT can miss early disease, and delay beyond 24 h to debridement multiplies mortality several-fold.
Prevent Recurrence at the Cause
Treat tinea pedis and any other skin break, since interdigital fissures are the commonest portal of entry.Manage edema with compression once the acute infection settles, and treat venous insufficiency and obesity. Consider prophylactic penicillin for 3 or more episodes per year (PATCH), which works while it is taken.
Inpatient falls are a "never event" -they cause hip fractures, subdural hematomas, and prolonged hospitalization. Delirium prevention is the same bundle. Most of this is medication review + non-pharmacologic interventions.
Diphenhydramine (Benadryl) -#1 offender on inpatient med lists. Also: hydroxyzine, oxybutynin, promethazine, cyclobenzaprine.
Cetirizine (non-sedating antihistamine). Acetaminophen for pain. Remove diphenhydramine from every PRN order set.
Opioids (excess)
High-dose PRN without scheduled non-opioid adjuncts
Scheduled acetaminophen 1g q6h. Add gabapentin for neuropathic. Use opioids for breakthrough only.
Antihypertensives (excess)
Home doses continued despite lower inpatient BP → orthostatic hypotension
Hold/reduce home antihypertensives if SBP < 120 or symptomatic orthostasis. Reassess at discharge.
Sedating antipsychotics
Quetiapine, chlorpromazine at high doses
Use lowest effective dose. Time-limit orders.
Non-Pharmacologic Prevention (HELP Protocol)
Reorientation -whiteboard with date, day, nurse name. Clock in room. Familiar objects. Family at bedside.
Sleep hygiene -lights off by 10 PM, minimize nighttime vitals, cluster care, earplugs + eye mask, avoid nighttime medication administration if possible
Early mobility -PT/OT consult on admission for at-risk patients. Ambulate TID minimum. Chair for meals (not bed).
Sensory aids -glasses and hearing aids AT BEDSIDE (not in a drawer). Dentures in for meals.
Remove tethers -Foley (remove by day 2 unless specific indication), unnecessary IV lines, telemetry if not needed, restraints (worsen agitation)
Nutrition + hydration -avoid NPO status if possible. Offer fluids. Malnutrition worsens delirium.
Avoid physical restraints -restraints increase agitation, prolong delirium, increase falls (patients climb over them), and increase mortality
The HELP (Hospital Elder Life Program) protocol reduces delirium incidence by 30-40%. It's entirely non-pharmacologic and costs nothing. It works better than any drug.
Key Evidence: The HELP program reduced delirium incidence by 40% using non-pharmacologic interventions Inouye (HELP), 1999. Antipsychotics do NOT prevent delirium in hospitalized patients Neufeld, 2016AID-ICU, 2018. Melatonin shows promise for sleep-wake cycle regulation but evidence is mixed Al-Aama, 2011.
🧪 Workup
Post-Fall Assessment
Assessment
What to Check
Action
Injury survey
Head (laceration, hematoma), hip/pelvis (pain on log-roll), spine (tenderness), extremities
CT head if head strike (mandatory if on anticoagulation). Hip X-ray if hip/groin pain. C-spine if neck pain.
Physical restraints do NOT prevent falls -they increase agitation, delirium, pressure injuries, aspiration, and functional decline. They are a last resort only for imminent self-harm, never routine fall prevention.
Non-pharmacologic delirium prevention bundle (HELP): Reorient frequently (clock, calendar, family photos). Mobilize early (PT by day 1-2). Remove unnecessary tethers (Foley, telemetry, restraints). Ensure glasses and hearing aids are at bedside. Promote sleep hygiene (lights off, minimize nighttime vitals). Avoid deliriogenic medications (Beers Criteria) AGS Beers Criteria, 2023.
💊 Medications
High-Risk Medications for Falls -Beers Criteria
Drug Class
Examples
Mechanism of Fall Risk
Action
Benzodiazepines
Lorazepam, diazepam, alprazolam
Sedation, impaired balance, cognitive slowing
Taper and discontinue. Use melatonin or trazodone for insomnia.
Liberalize BP target in frail elderly (SBP 150 may be acceptable).
Antipsychotics
Haloperidol, quetiapine
Sedation, orthostasis, EPS
Avoid for delirium if possible. If needed, use lowest dose × shortest duration.
Hypoglycemics
Sulfonylureas (glipizide), insulin
Hypoglycemia → syncope → fall
Liberalize glucose targets in elderly (A1c 7.5–8.5% acceptable).
Avoid benzodiazepines for delirium (except alcohol/benzo withdrawal). Benzodiazepines worsen confusion and increase fall risk. If pharmacologic management is needed for agitated delirium, use low-dose haloperidol 0.5-1 mg IV/PO or quetiapine 12.5-25 mg PO Devlin, 2010. Dexmedetomidine is preferred in ICU for delirious mechanically ventilated patients MENDS2, 2021.
Diphenhydramine is the #1 culprit. It appears on almost every inpatient PRN list as "sleep aid" or "allergy." It is strongly anticholinergic, causes delirium in elderly, and increases fall risk. Remove it from every order set. Alternatives: melatonin 3-5 mg for sleep, cetirizine for allergy Gray, 2015.
📋 On Rounds
Pimp Questions
Why is diphenhydramine (Benadryl) the worst PRN sleep medication for hospitalized elderly patients?
Diphenhydramine is a first-generation antihistamine with strong anticholinergic properties. In elderly patients, anticholinergics cause: (1) delirium (crosses BBB, blocks muscarinic receptors in CNS), (2) urinary retention (→ UTI, agitation from discomfort), (3) falls (sedation + orthostatic hypotension + impaired coordination), (4) constipation (→ more agitation).
What workup is mandatory after an inpatient fall in a patient on anticoagulation?
CT head without contrast -even if asymptomatic. Patients on anticoagulation (warfarin, DOACs, heparin) are at high risk for delayed intracranial hemorrhage, particularly subdural hematoma (SDH). SDH can present hours to days after a seemingly minor fall, and the patient may initially appear fine. If on warfarin, repeat CT head in 24 hours even if the initial CT is negative -delayed bleeds occur as INR fluctuates.
What is the Beers Criteria and why does every intern need to know it?
AGS Beers Criteria is a list of potentially inappropriate medications (PIMs) in adults ≥ 65 that increase fall risk, delirium, bleeding, and other harms. Key categories: (1) Anticholinergics: diphenhydramine, hydroxyzine, oxybutynin, cyclobenzaprine → delirium + falls. (2) Benzodiazepines: all of them → oversedation, falls, hip fractures. (3) Non-benzo hypnotics: zolpidem → falls, complex sleep behaviors
What medications most commonly contribute to falls in hospitalized patients?
The 'fall-risk' medication classes (overlaps heavily with Beers Criteria): (1) Benzodiazepines -sedation, impaired balance, cognitive slowing. Even short-acting (lorazepam) increases fall risk. (2) Opioids -sedation, orthostatic hypotension, cognitive impairment. (3) Antihypertensives -orthostatic hypotension (especially alpha-blockers, diuretics at night). (4) Anticholinergics -confusion, blurred vision, urinary retention → agitation
What is the HELP program and what did it show for delirium prevention?
Hospital Elder Life Program (HELP): multicomponent non-pharmacologic intervention targeting 6 delirium risk factors (cognitive impairment, sleep deprivation, immobility, visual/hearing impairment, dehydration). Inouye, 1999 (NEJM): Reduced delirium incidence by 40% in hospitalized elderly. Now the gold standard for delirium prevention. Costs less than pharmacologic approaches.
Clinical Examples
📋 Case 1, Inpatient Fall on Anticoagulation
Patient: 84F on apixaban for Afib, found on floor next to bed at 3 AM. Unwitnessed. Denies head strike but cannot recall details. Oriented, no focal deficits. Small forehead hematoma.
Key findings: High-risk fall: elderly + anticoagulation + possible head strike + unreliable history. Intracranial hemorrhage can present delayed in anticoagulated patients, symptoms may appear hours later.
Management:
CT head without contrast STAT (low threshold for imaging in anticoagulated patients with any head trauma)
Neuro checks q1h × 4h, then q2h × 8h (delayed ICH risk)
Fall risk assessment: Morse Fall Scale, bed alarm, non-skid socks, call light within reach, low bed position
PT/OT evaluation for mobility assessment, assistive device needs, home safety evaluation before discharge
Teaching point: In anticoagulated patients, CT head should be obtained for any fall with possible head strike, even if the patient looks fine. Subdural hematomas in elderly anticoagulated patients can be insidious, expanding slowly over hours to days before symptoms appear.
📋 Case 2, Recurrent Falls with Orthostatic Hypotension
Patient: 78M with HTN, BPH, T2DM. Third fall in 2 months. Home meds: amlodipine 10, doxazosin 4 mg, metoprolol 50 BID, trazodone 50 mg QHS. Orthostatic vitals: supine 148/82 → standing 108/58 with dizziness.
Key findings: Orthostatic hypotension (≥ 20 mmHg SBP drop or ≥ 10 mmHg DBP drop within 3 min of standing). Multiple contributing medications: doxazosin (alpha-blocker, worst offender), amlodipine, trazodone. Polypharmacy in elderly = falls.
Management:
Deprescribe doxazosin (alpha-blocker, highest fall risk of all antihypertensives, minimal CV benefit in elderly)
Switch BPH agent to tamsulosin 0.4 mg QHS (more uroselective, less orthostasis) or finasteride
Reduce amlodipine if BP allows (contributor to vasodilation)
Trazodone: assess if still needed for sleep, consider melatonin as safer alternative
Non-pharmacologic: rise slowly, sit at bedside 1 min before standing, compression stockings, adequate hydration
Teaching point: The #1 intervention for falls is medication review. Deprescribing fall-risk medications prevents more falls than any exercise program or environmental modification. Doxazosin is the classic "stop this drug" answer on falls assessment.
📋 Case 3, Fall with Hip Fracture
Patient: 82F with osteoporosis (T-score -3.4), fell from standing. Unable to bear weight on left leg. Left leg shortened and externally rotated. XR: left intertrochanteric hip fracture.
Key findings: Hip fracture from low-energy fall, pathologic fracture through osteoporotic bone. Hip fractures in elderly carry 20-30% 1-year mortality. Time to surgery is critical, OR within 24-48h reduces complications and mortality.
Management:
Orthopedic surgery consult for surgical fixation (intertrochanteric → intramedullary nail or sliding hip screw)
Surgery within 24-48h of admission (delay > 48h increases mortality, pneumonia, DVT, delirium)
Pain management: fascia iliaca block (regional anesthesia, superior to systemic opioids, reduces delirium risk)
DVT prophylaxis, delirium prevention (avoid benzos/anticholinergics, reorient, early mobility post-op)
Start osteoporosis treatment post-op: IV zoledronic acid after surgical healing + calcium/vitamin D (prevent next fracture)
Teaching point: A hip fracture is an orthopedic emergency, not an elective case. Every hour of surgical delay increases morbidity. The fascia iliaca block is a game-changer, it provides excellent pain control without the delirium risk of systemic opioids in elderly patients.
📣 Sample Presentation
One-Liner
"Mrs. Chen is an 85-year-old on apixaban who had an unwitnessed fall on the ward. She reports tripping on the IV tubing. No head strike per patient. Oriented, no focal deficits."
Key Points to Cover on Rounds
Unwitnessed fall on anticoagulation. No reported head strike but unwitnessed → CT head obtained (negative for acute intracranial hemorrhage). Neuro exam intact. Orthostatic vitals: positive (sitting→standing: 138/82→110/64). Medication review: amlodipine 10 mg (contributor to orthostatic hypotension) → reduced to 5 mg. Lorazepam 0.5 PRN sleep → discontinued. Foley removed (mobility barrier). PT evaluation: gait instability with walker. Plan: fall prevention bundle initiated, 24h repeat CT head (on apixaban), notify family, incident report filed.
Delayed SDH can develop. Even if initial CT negative.
Vitals + orthostatics
Daily until resolved
Orthostatic hypotension → adjust meds, IVF.
Morse Fall Scale
Each shift
Reassess fall risk. Update care plan.
Incident report
Immediately
Document fall circumstances, injuries, interventions. Notify family.
Monitoring Parameters -VTE / DVT
Parameter
Frequency
Target / Action
aPTT (heparin drip)
q6h until stable, then q12h
Target aPTT 60–80 sec (or per institutional protocol). Adjust infusion rate per nomogram.
INR (warfarin)
Daily while inpatient, then weekly → monthly when stable
Target INR 2.0–3.0. Bridge with heparin x 5 days AND until INR ≥ 2 for 24h before stopping heparin.
Platelets (HIT surveillance)
q2–3 days on heparin (days 4–14)
HIT: > 50% drop from baseline or platelets < 150K on heparin → check HIT antibody (PF4/heparin). 4T score to assess probability. If HIT → stop all heparin, start argatroban or bivalirudin.
Creatinine (DOAC dosing)
Baseline and periodically
CrCl determines DOAC eligibility. For VTE: apixaban approved down to CrCl 15 (AMPLIFY excluded < 25, so data weakest 15–25); rivaroxaban avoid < 30; dabigatran avoid < 30; edoxaban avoid < 15. For A-fib (different cutoffs): apixaban dose-reduce to 2.5 mg BID if ≥ 2 of (age ≥ 80, wt ≤ 60, Cr ≥ 1.5); rivaroxaban 15 mg daily if CrCl 15–50. Declining renal function may require switch to warfarin.
Bleeding symptoms
Each assessment
GI bleeding (melena, hematochezia), hematuria, gum bleeding, easy bruising, menorrhagia. Any major bleed → hold anticoagulation, assess need for reversal.
Recurrent VTE symptoms
Each assessment + patient education
New leg swelling/pain → repeat ultrasound. New dyspnea/chest pain → CTPA. Recurrence on anticoagulation → consider non-compliance, cancer workup, APS testing.
HIT surveillance is critical on heparin. Check platelets baseline, then q2–3 days from days 4–14. A > 50% drop is the trigger -not an absolute threshold. Use the 4T score before sending the expensive PF4 antibody.
Inpatient falls cause hip fractures, subdural hematomas and prolonged admissions, and are classed as never events.The prevention bundle is the same one that prevents delirium, because the drivers, immobility, sedatives, sensory deprivation and disorientation, are identical.
HELP Works Better Than Any Drug
The Hospital Elder Life Program reduces delirium incidence by 30 to 40%, is entirely non-pharmacologic and costs nothing. Orientation, early mobilization, sleep protocols without sedatives, vision and hearing aids in place, hydration and feeding assistance. No medication comes close to that effect size.
The Medication List Is the Highest-Yield Intervention
Review and stop what you can: benzodiazepines, Z-drugs, antipsychotics, anticholinergics, opioids, tricyclics, muscle relaxants, alpha blockers and any drug causing orthostasis. Beers criteria name these explicitly.Most inpatient falls have a medication contribution, and deprescribing is faster and safer than any monitoring device.
Do Not Prescribe Sedatives for Sleep or Agitation
Benzodiazepines and Z-drugs cause the delirium and the falls they are given to manage, and antipsychotics carry a mortality warning in dementia without preventing falls. Use non-pharmacologic sleep measures and reserve antipsychotics for severe agitation with a danger to the patient or staff, at the lowest dose for the shortest time.
Bed Alarms and Restraints Do Not Prevent Falls
Bed alarms have not reduced fall rates in trials, and physical restraints increase injury, agitation, deconditioning and delirium.Mobility, not immobilization, is what protects these patients, and a sitter or family presence achieves more than any device.
Check Orthostatics and the Senses
Lying and standing blood pressure, and a medication review aimed at the cause.Make sure glasses and hearing aids are actually on the patient: sensory deprivation is a leading and completely reversible contributor to both falls and delirium, and the devices are frequently left in a drawer at home or in a bag by the bed.
Assess Properly After a Fall
Look for injury, above all head injury and hip fracture, and image the head if the patient is anticoagulated or hit their head.Then ask why they fell: syncope, arrhythmia, orthostasis, hypoglycemia, stroke, infection, or a new medication. A fall is a symptom, not an event, and treating it as an incident report rather than a diagnosis misses the cause.
Plan the Discharge Around It
Physical and occupational therapy assessment, a home safety evaluation, and assistive devices fitted properly.Check vitamin D, treat osteoporosis, and review the outpatient medication list with the same rigor.A fall in hospital predicts falls at home, so the intervention has to leave with the patient.
RoundsRx Infographic Series · #184 · General Medicine · PDF 140 KB
Text version
INPATIENT FALL -AT A GLANCE
🔍 Assess: Injury survey, neuro exam, orthostatics, ECG 🧪 Labs: BMP (Na, glucose, Ca), CBC, INR if on warfarin 🧠 CT head: If head strike + anticoag → STAT + repeat 24h 💊 Meds: Deprescribe benzos, anticholinergics, opioids 🛏️ Prevent: Bed alarm, clear path, HELP protocol, PT/OT 📋 Document: Incident report, family notification
Assess for injury: head strike → CT head (especially if on anticoagulation -delayed SDH). Hip pain → hip X-ray. Neuro exam.
On anticoagulant + head strike: CT head STAT even if asymptomatic. Repeat in 24h if on warfarin (delayed bleed).
Root cause: what was the patient doing? Medication-related? Orthostatic? Environmental (wet floor, cords)? Delirium? Seizure? Syncope?
Incident report + family notification + attending notification + documentation
HematologyCore
VTE Prophylaxis & Treatment
Every hospitalized patient needs VTE risk assessment. DVT and PE are preventable causes of inpatient death -know when to prophylax, how to diagnose, and how to treat.
🔍 Overview
VTE Spectrum
Venous thromboembolism (VTE) encompasses deep vein thrombosis (DVT) and pulmonary embolism (PE). PE is a DVT that has embolized to the pulmonary vasculature. ~600,000 VTE events/year in the US; ~100,000 deaths/year. Hospital-acquired VTE is the #1 preventable cause of hospital death.
Virchow's Triad
Stasis: Immobility, hospitalization, long flights, paralysis, obesity
Endothelial injury: Surgery, trauma, central lines, prior DVT, vasculitis
Hypercoagulability: Cancer (#1 acquired), pregnancy, OCP/HRT, Factor V Leiden, prothrombin mutation, antiphospholipid syndrome, nephrotic syndrome
Padua Prediction Score (VTE Prophylaxis)
Risk Factor
Points
Active cancer
3
Previous VTE (excluding SVT)
3
Reduced mobility (≥ 3 days)
3
Known thrombophilia
3
Recent (≤ 1 month) surgery or trauma
2
Age ≥ 70
1
Heart or respiratory failure
1
Acute MI or stroke
1
Acute infection or rheumatic disorder
1
Obesity (BMI ≥ 30)
1
Ongoing hormonal treatment
1
Padua ≥ 4 = High risk → pharmacologic prophylaxis. Padua < 4 = Low risk → ambulation + SCDs only. Also assess bleeding risk (IMPROVE score) before starting anticoagulation prophylaxis.
Key Facts
~50% of hospital DVTs are asymptomatic. Prophylaxis prevents them before they embolize.
Chronic thromboembolic pulmonary hypertension (CTEPH): ~4% of PE patients. Screen if persistent dyspnea after PE treatment.
Cancer-associated VTE: 4-7x increased risk. Consider occult cancer workup in unprovoked VTE (age-appropriate screening).
📋 On Rounds
Pimp Questions
What is the Padua Prediction Score and when do you give pharmacologic VTE prophylaxis?
Padua score stratifies VTE risk in medical patients. Score >= 4 = high risk, start pharmacologic prophylaxis (enoxaparin 40 mg SQ daily or heparin 5000 units SQ q8h). Score < 4 = low risk, ambulation + SCDs only. Key high-point items: active cancer (3), prior VTE (3), reduced mobility >= 3 days (3), known thrombophilia (3). Also assess bleeding risk (IMPROVE score) before anticoagulation.
What is the difference between the Wells score for DVT and the Wells score for PE?
Two separate scoring systems. DVT Wells: max ~9 points, score >= 2 = DVT likely (go to US), < 2 = unlikely (D-dimer first). PE Wells: max ~12.5 points, score > 4 = PE likely (CTPA directly), <= 4 = unlikely (D-dimer first). Key difference: PE Wells heavily weights clinical suspicion (PE most likely dx = 3 pts) and DVT signs (3 pts). Both use '-2' for alternative diagnosis. Never combine them.
When can you use the PERC rule to rule out PE without a D-dimer?
PERC applies ONLY to LOW pre-test probability patients. All 8 criteria must be negative: age < 50, HR < 100, SpO2 >= 95%, no hemoptysis, no estrogen use, no prior DVT/PE, no unilateral leg swelling, no surgery/trauma in 4 weeks. If all 8 negative, PE is ruled out without D-dimer (miss rate < 2%). Do NOT apply PERC to moderate or high pre-test probability patients. Kline et al., 2004
What is the age-adjusted D-dimer cutoff and why is it important?
For patients > 50 years old, the D-dimer cutoff = age x 10 ng/mL (e.g., 65-year-old = 650 instead of 500). D-dimer specificity decreases with age, leading to excessive CTPAs in elderly patients. The ADJUST-PE trial showed age-adjusted cutoffs increased specificity from 34% to 46% without missing any PEs, reducing unnecessary CTPAs by ~12%. Only use in PE-unlikely patients (Wells <= 4). ADJUST-PE, 2014
A patient with cancer develops a DVT. What anticoagulant do you use and why?
For cancer-associated VTE, LMWH (enoxaparin) was the historical standard based on the CLOT trial (52% recurrence reduction vs warfarin). Now DOACs (edoxaban per HOKUSAI-VTE Cancer, rivaroxaban per SELECT-D) are alternatives with similar efficacy and convenience. EXCEPTION: avoid DOACs in GI or GU cancers due to significantly higher mucosal bleeding risk. Warfarin is avoided in cancer (drug interactions, unreliable INR, inferior outcomes). Duration: as long as cancer is active. CLOT, 2003
When do you give tPA for PE and when do you NOT?
tPA (alteplase 100 mg IV over 2h) is indicated for CATEGORY E PE only (formerly massive): sustained SBP < 90 for > 15 min, cardiac arrest, or persistent profound bradycardia. Do NOT give for Category C3 (RV strain + normal BP, formerly submassive) - the PEITHO trial reduced hemodynamic collapse but increased intracranial hemorrhage (2.4%) and major bleeding (6.3%). Category C3 = heparin + ICU monitoring + close observation for deterioration. PEITHO, 2014
How long do you anticoagulate after a first VTE?
Provoked by major transient risk (surgery, immobilization): 3 months. Provoked by minor risk (travel, estrogen): 3 months, consider extending. Unprovoked: minimum 3 months, then reassess - often extended indefinitely if low bleeding risk. Recurrent unprovoked: indefinite. Cancer-associated: as long as cancer is active. D-dimer after stopping anticoagulation helps guide (PROLONG study - elevated D-dimer after stopping = high recurrence risk, restart). PROLONG, 2006
What is HIT and how do you manage it?
Heparin-induced thrombocytopenia: immune-mediated platelet activation via PF4-heparin antibodies. Suspect when platelets drop > 50% from baseline on days 5-14 of heparin exposure. Use 4T score to risk-stratify. Management: STOP ALL heparin immediately (including flushes and line locks). Start a non-heparin anticoagulant (argatroban if hepatic function okay, bivalirudin if renal failure). Send PF4 antibody + SRA. Do NOT give warfarin until platelets > 150K (risk of venous limb gangrene).
Why is apixaban preferred over warfarin for most non-cancer VTE?
The AMPLIFY trial showed apixaban was non-inferior to warfarin for preventing recurrent VTE (2.3% vs 2.7%) with 56% less major bleeding (0.6% vs 1.8%). Advantages over warfarin: no heparin bridge needed (load 10 mg BID x 7 days then 5 mg BID), no INR monitoring, fewer drug-food interactions, predictable pharmacokinetics, rapid onset. Disadvantages: cost, limited reversal agents (andexanet alfa), less data in severe renal failure or mechanical valves. AMPLIFY, 2013
Q: What is the Wells Score for PE?
A: Clinical signs of DVT (3), PE most likely dx (3), HR > 100 (1.5), immobilization/surgery in 4 wks (1.5), prior DVT/PE (1.5), hemoptysis (1), cancer (1). Score > 4 = PE likely → CTPA. Score ≤ 4 = PE unlikely → D-dimer first. Simplifies to 2-tier: likely vs unlikely.
Q: When can you use PERC to rule out PE?
A: Only in LOW pre-test probability patients. All 8 must be negative: age < 50, HR < 100, O2 sat ≥ 95%, no hemoptysis, no estrogen use, no prior DVT/PE, no unilateral leg swelling, no surgery/trauma in 4 weeks. If ALL negative → PE ruled out without D-dimer. Misses < 2%.
Q: What is the age-adjusted D-dimer cutoff?
A: For patients > 50: cutoff = age × 10 (e.g., 65yo → cutoff 650 ng/mL instead of 500). Validated in ADJUST-PE trial -increased specificity from 34% to 46% without missing PEs. Only use in PE-unlikely patients. Reduces unnecessary CTPAs by ~12%.
Q: What anticoagulant do you use for cancer-associated VTE?
A: LMWH was standard (CLOT trial). Now DOACs (edoxaban per HOKUSAI-VTE Cancer, rivaroxaban per SELECT-D) are alternatives EXCEPT in GI/GU cancers (higher bleeding risk with DOACs). Avoid warfarin in cancer -harder to manage, drug interactions, unreliable INR.
Q: When do you give tPA for PE?
A: Category E only (formerly massive): sustained hypotension (SBP < 90 for > 15 min), pulselessness, or persistent bradycardia. Alteplase 100mg IV over 2h is standard. NOT for Category C3 (RV strain + normal BP) -PEITHO trial showed tPA reduced hemodynamic collapse but increased ICH. Category C3 = anticoagulation + close monitoring.
Q: How long do you anticoagulate after a first VTE?
A: Provoked (surgery, immobility): 3 months. Unprovoked: minimum 3 months, then reassess -often extended/indefinite if low bleeding risk. Cancer: treat as long as cancer is active. Recurrent unprovoked: indefinite. Use D-dimer after stopping to guide (PROLONG study).
Clinical Examples
Case 1: DVT -Provoked
58M, 5 days post-TKR, left calf swelling and tenderness. D-dimer 2400. Duplex US: acute occlusive thrombus in left popliteal vein. Dx: Provoked proximal DVT. Start enoxaparin (Lovenox) 1mg/kg BID, bridge to apixaban (Eliquis). Duration: 3 months (provoked by surgery).
Case 2: Category C3 PE
45F on OCPs presents with acute dyspnea, HR 115, BP 110/70, SpO2 91%. CTPA: bilateral PE with RV/LV ratio > 1. Troponin 0.15. BNP 450. Dx: Category C3 PE, formerly submassive (RV strain + elevated biomarkers, but hemodynamically stable). Start heparin drip. Monitor closely in ICU. tPA NOT indicated unless hemodynamic decompensation. PEITHO, 2014
Case 3: Cancer-Associated VTE
62F with metastatic pancreatic cancer, found to have incidental PE on staging CT. Asymptomatic, hemodynamically stable. Dx: Cancer-associated VTE. Start enoxaparin (Lovenox) 1mg/kg BID (preferred over DOAC in GI malignancy due to bleeding risk). CLOT, 2003 Duration: as long as cancer is active or on treatment.
Case 4: HIT with DVT
70M on heparin drip for DVT, day 7. Platelets dropped from 220K to 85K (60% decline). 4T score: 6 (high probability). Dx: HIT. STOP all heparin immediately (including flushes). Start argatroban (direct thrombin inhibitor). Send PF4 antibody + SRA. Do NOT give warfarin until platelets > 150K (risk of warfarin-induced venous limb gangrene).
Sample Presentation
Mrs. Thompson is a 52-year-old woman presenting with 3 days of left leg swelling and pain. She returned from a 12-hour flight 5 days ago. No prior VTE. On estrogen HRT. Exam: left calf 3cm larger than right, pitting edema, tenderness along deep veins, positive Homan's sign. Wells DVT score: 3 (calf swelling > 3cm, pitting edema, entire leg swollen). D-dimer: 1,800 ng/mL.
Key Points: High pre-test probability DVT (Wells ≥ 2 + elevated D-dimer). Obtain duplex ultrasound to confirm. Risk factors: prolonged travel + estrogen. If proximal DVT confirmed, start anticoagulation (apixaban preferred for non-cancer VTE). Duration 3 months if provoked (travel + estrogen). Counsel to stop HRT. No thrombophilia workup needed for first provoked event.
Daily Rounds Checklist
VTE prophylaxis ordered? Check every patient, every day. Document reason if held.
Immobilization (≥ 3 days) or surgery in prior 4 weeks
1.5
Previous DVT/PE
1.5
Hemoptysis
1
Malignancy (treatment in last 6 months or palliative)
1
Score > 4 (PE likely): → CTPA directly. Score ≤ 4 (PE unlikely): → D-dimer first. Use age-adjusted D-dimer (age × 10 for patients > 50) ADJUST-PE, 2014
PERC Rule (PE Rule-Out Criteria)
PERC: Use ONLY if pre-test probability is LOW. All 8 must be negative to rule out PE without D-dimer: Age < 50, HR < 100, SpO2 ≥ 95%, no hemoptysis, no estrogen, no prior DVT/PE, no unilateral leg swelling, no surgery/trauma in 4 weeks.
Imaging
Duplex ultrasound: First-line for DVT. Sensitivity 94%, specificity 98% for proximal DVT. Lower sensitivity for calf DVT (~70%).
CTPA: Gold standard for PE. Sensitivity 83-100%, specificity 89-97%. PIOPED II, 2006
V/Q scan: Alternative if CTPA contraindicated (contrast allergy, renal failure). Best when CXR is normal. Reports as normal/low/intermediate/high probability.
Bedside echo: RV dilation, RV hypokinesis, McConnell's sign (RV free wall akinesis with apical sparing). Useful in Category E PE when too unstable for CTPA.
PE Risk Stratification
Category
Hemodynamics
RV Dysfunction
Biomarkers
Mortality
Treatment
Massive
SBP < 90 or arrest
Yes
Elevated
25-65%
tPA + heparin
Category C3
Normal
Yes
Elevated (troponin/BNP)
3-15%
Heparin + ICU monitoring
Low-risk
Normal
No
Normal
< 1%
Anticoagulation
💊 Treatment
VTE Prophylaxis
Agent
Dose
Notes
Enoxaparin (Lovenox)
40mg SQ daily
First-line medical prophylaxis. Adjust for CrCl < 30 (30mg daily). Hold if platelets < 50K or active bleeding.
Heparin (UFH)
5000 units SQ q8h
Use if CrCl < 30 or high bleeding risk (can reverse with protamine). TID dosing > BID for medical patients.
SCDs (mechanical)
Bilateral
Use alone if active bleeding, platelets < 50K, or high bleed risk. Use WITH pharmacologic in highest-risk patients. Remove for ambulation.
Fondaparinux (Arixtra)
2.5mg SQ daily
Alternative if HIT history. No platelet monitoring needed. Contraindicated CrCl < 30.
VTE prophylaxis is a quality measure. Every medical patient with Padua ≥ 4 and every surgical patient should have pharmacologic prophylaxis unless contraindicated. Document the reason if held (active bleeding, platelets < 50K, etc).
Acute Treatment
Agent
Dose
Monitoring
Notes
Heparin drip (UFH)
80 units/kg bolus → 18 units/kg/hr
aPTT q6h → q12h when stable
Use for Category E PE, renal failure, high bleed risk (short half-life, reversible)
Enoxaparin (Lovenox)
1mg/kg SQ BID or 1.5mg/kg daily
Anti-Xa if obese or renal impairment
Preferred for most DVT. Avoid if CrCl < 30.
Apixaban (Eliquis)
10mg BID × 7 days → 5mg BID
None routinely
No heparin lead-in needed. First-line for non-cancer VTE. AMPLIFY, 2013
Rivaroxaban (Xarelto)
15mg BID × 21 days → 20mg daily
None routinely
No heparin lead-in. Once-daily maintenance. EINSTEIN-PE, 2012
Warfarin (Coumadin)
Target INR 2.0-3.0
INR daily → weekly → monthly
Requires 5-day heparin bridge. Cheap. Use if mechanical valve, APS, severe renal failure.
Edoxaban (Savaysa)
60mg daily (after 5-day heparin lead-in)
None routinely
Requires parenteral lead-in. Reduce to 30mg if CrCl 15-50 or weight ≤ 60kg. HOKUSAI-VTE, 2013
Duration of Anticoagulation
Scenario
Duration
Rationale
Provoked by major transient risk (surgery, immobilization)
3 months
Low recurrence risk once risk factor resolved (~3%/year)
Provoked by minor transient risk (travel, estrogen, minor injury)
3 months (consider extended)
Intermediate recurrence risk. Reassess at 3 months.
Unprovoked (first event)
≥ 3 months → reassess
15% recurrence at 2 years if stopped. Extend if low bleed risk. D-dimer after stopping helps guide (PROLONG).
Recurrent unprovoked
Indefinite
~30% recurrence if stopped. Benefit of continued anticoagulation outweighs bleeding risk.
Cancer-associated
As long as cancer active
LMWH or DOAC (not warfarin). Reassess every 3-6 months. CLOT, 2003
Special Situations
Cancer-associated VTE:LMWH or edoxaban/rivaroxaban (avoid DOACs in GI/GU cancers -bleeding). Avoid warfarin. Treat indefinitely while cancer active.
Pregnancy:LMWH only (enoxaparin 1mg/kg BID). Warfarin is teratogenic. DOACs contraindicated. Hold LMWH 24h before delivery.
Renal failure (CrCl < 30): UFH or dose-adjusted LMWH (enoxaparin 1mg/kg daily, monitor anti-Xa). Warfarin safe. Apixaban can be used (less renal clearance). Avoid rivaroxaban, edoxaban.
HIT: Stop ALL heparin. Start argatroban (hepatic metabolism, use in renal failure) or bivalirudin. Transition to warfarin only after platelets > 150K. Fondaparinux is an alternative.
Obesity (> 120kg or BMI > 40): Use weight-based LMWH with anti-Xa monitoring. DOACs may have reduced efficacy (limited data). Consider heparin drip for acute treatment.
DOAC Unified Comparison
DOAC
VTE dosing
Renal cutoffs
Reversal agent
Notes
Apixaban (Eliquis) PREFERRED non-cancer
10 mg BID × 7 d → 5 mg BID. Extended Rx: 2.5 mg BID after 6 mo.
Avoid CrCl < 25 (no dose data). Approved down to CrCl 15 by FDA but data weak.
Lowest major-bleed signal of any DOAC (AMPLIFY 0.6%). No food restriction. Twice-daily dosing the only downside.
Rivaroxaban (Xarelto)
15 mg BID × 21 d → 20 mg daily with food. Extended Rx: 10 mg daily after 6 mo.
Avoid CrCl < 30 for VTE.
Andexanet alfa · 4F-PCC 50 u/kg.
Once-daily after the 21-day load. Must take with food (absorption ↑ 39%). Slightly higher GI bleeding signal than apixaban.
Edoxaban (Savaysa)
60 mg daily AFTER 5-10 days of parenteral lead-in (heparin or LMWH). Reduce to 30 mg if CrCl 15-50, weight ≤ 60 kg, or strong P-gp inhibitor.
Avoid CrCl < 15.
Andexanet alfa (off-label) · 4F-PCC.
Used in HOKUSAI-VTE Cancer for cancer-associated VTE. Lead-in requirement makes it less convenient than apixaban/riva.
Dabigatran (Pradaxa)
150 mg BID AFTER 5-10 days of parenteral lead-in.
Avoid CrCl < 30.
Idarucizumab (Praxbind) 5 g IV -specific antidote, works within minutes.
Direct thrombin inhibitor (others are factor Xa). High GI bleeding signal at 150 mg dose. Best reversal of any DOAC. Dyspepsia common.
Anticoagulation Reversal -Major Bleeding
Major bleeding: intracranial hemorrhage, retroperitoneal bleed, hemodynamic compromise, transfusion ≥ 2 units, drop in Hgb ≥ 2 g/dL, or bleeding into a critical site. Stop the anticoagulant, apply local hemostasis, transfuse as needed, and reverse with the agent below.
Anticoagulant
Reversal
Dose / Notes
Warfarin
4F-PCC (Kcentra) + Vitamin K 10 mg IV
4F-PCC dose by INR: INR 2-4 → 25 u/kg; INR 4-6 → 35 u/kg; INR > 6 → 50 u/kg (max 5000 u). Faster and less volume than FFP. Always co-give Vitamin K 10 mg IV -PCC effect lasts ~6 h, Vit K provides durable reversal. FFP only if PCC unavailable (15-30 mL/kg).
Unfractionated heparin (UFH)
Protamine sulfate
1 mg per 100 units of heparin given in the last hour. Last 1-2 h → 0.5 mg per 100 u. Last 2-4 h → 0.25 mg per 100 u. Max 50 mg single dose. Watch for hypotension and anaphylaxis (especially in fish-allergy or prior protamine exposure -e.g., NPH insulin patients).
LMWH (enoxaparin)
Protamine -partial reversal only
Reverses ~60% of anti-Xa activity. Within 8 h of dose: 1 mg protamine per 1 mg enoxaparin. 8-12 h after dose: 0.5 mg per 1 mg. > 12 h: not effective. Consider 4F-PCC if life-threatening.
Apixaban / Rivaroxaban / Edoxaban (Factor Xa inhibitors)
Andexanet alfa (Andexxa) 1st-line · 4F-PCC alternative
Andexanet bolus + 2-h infusion (low-dose 400 mg + 4 mg/min, or high-dose 800 mg + 8 mg/min depending on agent / time / dose). Alternative: 4F-PCC 50 u/kg if andexanet unavailable, cost-prohibitive, or contraindicated. ANNEXA-4, 2019
Dabigatran (direct thrombin inhibitor)
Idarucizumab (Praxbind) 5 g IV -specific antidote
Two 2.5 g vials given consecutively over 5-10 min. Reversal within minutes (binds dabigatran 350× more tightly than thrombin). RE-VERSE AD, 2017. Hemodialysis is an alternative (60% removal in 2 h) -useful in advanced renal failure.
Argatroban / Bivalirudin (used in HIT)
No specific reversal
Stop infusion. Argatroban half-life ~50 min, bivalirudin ~25 min. Supportive care + transfusion. 4F-PCC may be considered if life-threatening but data limited.
Fondaparinux
No proven reversal
Stop the drug. Half-life 17-21 h. Recombinant factor VIIa has been tried (limited data, off-label). Consider 4F-PCC empirically. Hemodialysis ineffective.
Last-dose timing matters more than the lab number for DOACs. Specific anti-Xa or dabigatran levels are not routinely available; time since last dose drives the reversal decision. If the last dose was > 24-48 h ago in a patient with normal renal function, the drug is largely cleared and reversal may not be needed. Always confirm timing before reversing.
Thrombolysis & Catheter-Directed Therapy for PE
Category E PE, formerly massive (SBP < 90 × 15 min, cardiac arrest, or persistent bradycardia):Alteplase (tPA) 100 mg IV over 2 hours (or 50 mg bolus in arrest). Give WITH heparin. Absolute contraindications: active internal bleeding, recent (2 months) CVA, intracranial neoplasm. Mortality benefit outweighs bleed risk in Category E.
Modality
Indication
Procedure
Evidence
Systemic tPA
Category E PE (hemodynamic compromise) only. NOT for Category C3 alone.
Alteplase 100 mg IV over 2 h, OR 50 mg bolus in cardiac arrest. Heparin co-administered.
PEITHO, 2014 -systemic lysis in submassive PE causes more harm than good.
Catheter-directed thrombolysis (CDT)
Category C3 to D (RV strain, formerly submassive) where systemic lysis is too risky; or Category E with relative contraindication to systemic.
Catheter advanced into pulmonary artery; low-dose alteplase (1 mg/h × 12-24 h, total dose 10-24 mg) infused locally. EKOS adds ultrasound to fragment clot.
ULTIMA, 2014 · SEATTLE II, 2015
Mechanical thrombectomy (catheter aspiration)
Massive or intermediate-high-risk PE, especially when thrombolytics contraindicated. Increasingly used as first-line in Category C3 to D.
FlowTriever (Inari) -large-bore aspiration catheter; mechanical thrombus removal without lytic. Penumbra Indigo -aspiration. No tPA needed.
FLARE, 2019 · FLAME, 2023 · PEERLESS, 2024
Surgical embolectomy
Category E PE with absolute contraindication to all thrombolytics AND failed CDT/mechanical, OR clot-in-transit through PFO with paradoxical embolism risk.
Median sternotomy, cardiopulmonary bypass, direct extraction.
Largely superseded by catheter-based options. Reserved for centers with surgical expertise.
VA-ECMO
Cardiac arrest from PE or refractory shock as a bridge to definitive therapy (CDT, thrombectomy, or recovery).
Veno-arterial ECMO provides circulatory support while thrombus resolves or is removed.
Increasingly used at PERT-equipped centers. PERT consortium data supports multidisciplinary approach.
Activate PERT (Pulmonary Embolism Response Team) for any massive or intermediate-high-risk PE if your hospital has one. Cardiologists, IR, pulmonary, and CT surgery convene rapidly to choose between systemic lysis, CDT, mechanical thrombectomy, or surgical embolectomy. Time-to-decision matters as much as the choice.
HIT 4T Score
Category
2 points
1 point
0 points
Thrombocytopenia
Platelet drop > 50% AND nadir ≥ 20K
Drop 30-50% OR nadir 10-19K
Drop < 30% OR nadir < 10K
Timing
Days 5-10 (or < 1 day with prior heparin in last 30 d)
Possibly 5-10 (no clear records) or > 10 days
< 4 days without prior exposure
Thrombosis
New thrombosis · skin necrosis at injection site · acute systemic reaction after IV bolus
Score 0-3 = low probability (HIT essentially excluded; PF4 antibody not needed). 4-5 = intermediate (send PF4 ELISA; stop heparin pending result). 6-8 = high (stop ALL heparin immediately, start non-heparin anticoagulant -argatroban or bivalirudin -before lab confirmation; send PF4 + serotonin release assay).
IVC Filter
Indication: Acute proximal DVT or PE with absolute contraindication to anticoagulation (active major bleeding, recent CNS surgery)
Retrievable filters preferred -remove once anticoagulation can be restarted (filter itself increases DVT risk)
NOT indicated as adjunct to anticoagulation in most cases
⚡ Summary
Summary
Assess Every Inpatient
Hospital-acquired VTE is a preventable cause of inpatient death, and failing to order prophylaxis is a safety event rather than an oversight. Padua 4 or more in medical inpatients means pharmacologic prophylaxis; Caprini stratifies surgical patients. Reassess when the clinical picture changes.
Diagnose With a Pretest Probability, Not a D-Dimer Alone
Wells for DVT and PE.D-dimer is a rule-out test only in low or intermediate probability: it is raised by age, pregnancy, cancer, infection, surgery and inflammation, so a positive result in a high-probability patient adds nothing. Use age-adjusted D-dimer above 50 (age × 10) to cut unnecessary imaging.
Know When PERC Applies
PERC only rules out PE in a patient who is already low risk by gestalt.All eight criteria must be negative, and then no further testing is needed. Applying PERC to a moderate or high-probability patient is misuse and misses PE.
Imaging by Site
Compression ultrasound for DVT.CT pulmonary angiography for PE, with V/Q scanning where contrast is contraindicated, in renal failure, or in pregnancy.Bedside echocardiography in an unstable patient, where right ventricular strain supports the diagnosis fast enough to act on.
Risk-Stratify PE Before Choosing Treatment
Massive (high-risk): sustained hypotension or shock → systemic thrombolysis or catheter-directed therapy.Category C3 (elevated severity): right ventricular strain on echo or CT with a positive troponin, but normotensive → anticoagulate and monitor closely, with thrombolysis reserved for deterioration (PEITHO showed reduced decompensation but excess major bleeding and intracranial hemorrhage). Low risk → anticoagulate, and consider outpatient management using sPESI or Hestia.
DOACs Are First Line, With Named Exceptions
Apixaban and rivaroxaban start without a heparin lead-in; dabigatran and edoxaban need 5 days of parenteral therapy first.Use warfarin, not a DOAC, in antiphospholipid syndrome (higher arterial event rates on rivaroxaban), in mechanical valves, and in severe renal impairment. LMWH remains preferred in pregnancy and is a reasonable choice in cancer, where DOACs are also acceptable but raise GI bleeding with luminal tumors.
Duration Is Decided by Provocation
Provoked by a major transient risk factor (surgery, trauma, immobility): 3 months.Unprovoked: at least 3 months, then consider extended therapy, since recurrence after stopping is high. Active cancer: continue while the cancer is active.Recurrent unprovoked VTE: indefinite.Reduced-dose apixaban or rivaroxaban is an option for extended therapy, keeping most of the protection with less bleeding.
Reverse Only for Real Bleeding, and Know the Agent
Warfarin: 4-factor PCC plus vitamin K. Dabigatran: idarucizumab. Apixaban and rivaroxaban: andexanet alfa, or PCC where it is unavailable.An IVC filter is for anticoagulation failure or an absolute contraindication to anticoagulation, not as an add-on, and it must have a documented retrieval plan, because a filter left indefinitely causes its own thrombosis. Consider a thrombophilia workup only when the result would change duration, and never during the acute event or while anticoagulated, when the assays are uninterpretable.
RoundsRx Infographic Series · #149 · Hematology · PDF 150 KB
Text version
One-Pager
VTE Prophylaxis & Treatment
DVT/PE Management
Prophylaxis
Padua ≥ 4 → enoxaparin 40mg SQ daily. CrCl < 30 → heparin 5000u q8h. Active bleeding → SCDs only. EVERY patient needs VTE risk assessment on admission. Document if held.
Diagnosis Algorithm
DVT: Wells → if ≥ 2 → US; if < 2 → D-dimer. PE: PERC → Wells → if ≤ 4 → D-dimer (age-adjusted > 50); if > 4 → CTPA. Category E PE: bedside echo (RV dilation, McConnell's).
Acute Treatment
Non-cancer: apixaban 10mg BID × 7d → 5mg BID (no heparin lead-in). Cancer: LMWH (not DOAC in GI/GU). Category E PE: tPA 100mg/2h + heparin. HIT: stop heparin → argatroban.
Key Trials
AMPLIFY (apixaban) · EINSTEIN (rivaroxaban) · HOKUSAI-VTE (edoxaban) · CLOT (LMWH in cancer) · ADJUST-PE (age-adjusted D-dimer) · PEITHO (tPA in submassive PE -don't do it) · PIOPED II (CTPA).
A safe discharge prevents readmission. Medication reconciliation, follow-up, patient education, and safety-net instructions are the four pillars. Readmission within 30 days is often a failure of discharge, not disease.
✅ Discharge Checklist
Before Writing the Discharge Order
Medication reconciliation -compare admission meds vs discharge meds. What was added? Changed? Stopped? Does the patient understand each change and why?
Labs pending? -do NOT discharge with critical pending results (blood cultures, pathology). If minor labs pending → ensure follow-up plan for results.
Follow-up appointments -PCP within 7–14 days for all discharges. Specialist follow-up as needed (cardiology post-ACS, surgery post-op, oncology). High-risk patients: follow-up within 48–72h.
Discharge medications prescribed + sent to pharmacy. Verify the patient can afford them. Prior authorizations done? Assistance programs if needed.
Patient education -diagnosis explained in plain language. Red flags to return to ED. Medication side effects. Activity restrictions. Diet changes (low-sodium for HF, renal diet for CKD).
Durable medical equipment -O₂ arranged? CPAP? Walker/wheelchair? Home health nursing?
Social work / care coordination -safe living situation? Capable of ADLs? Need rehab (SNF, acute rehab, LTAC)? Substance use resources? Mental health follow-up?
VTE prophylaxis post-discharge -does the patient need extended prophylaxis (post-major orthopedic surgery × 35 days, post-cancer surgery)?
Discharge summary completed -timely, sent to PCP. Include: admission diagnosis, hospital course, key results, discharge meds (with changes highlighted), pending results, follow-up plan, and code status discussion if applicable.
High-Risk Discharges (30-Day Readmission Risk)
Condition
Key Discharge Interventions
Heart Failure
Daily weights at home. Fluid restrict 1.5–2 L/day. Low-sodium diet. Follow-up within 7 days. Action plan: "If weight ↑ 3 lbs in 2 days → call clinic / double Lasix."
Document capacity assessment, risks explained, medications offered, follow-up arranged despite AMA. Patients retain right to receive discharge meds and instructions.
I-PASS Sign-Out Format
Letter
Meaning
Example
I
Illness severity
"Stable" / "Watcher" / "Unstable"
P
Patient summary
"72M with COPD exacerbation, day 3 of prednisone, on 2L NC"
A
Action list
"Repeat BMP at 6 AM for K⁺ recheck. Call if below 3.5."
S
Situation awareness
"May need BiPAP if RR > 30 or SpO₂ < 88%. Has been borderline."
S
Synthesis by receiver
Receiving team reads back key action items and contingency plans.
I-PASS reduced medical errors by 23% and preventable adverse events by 30% in a multicenter study I-PASS Study, 2014.
💊 Medications
Medication Reconciliation -The #1 Safety Issue
~50% of patients have ≥ 1 medication discrepancy at discharge. The three most dangerous: (1) restarting a med that was intentionally held, (2) not starting a new med that was added, (3) duplicate therapy.
Step
Action
1. Compare lists
Home meds → inpatient meds → discharge meds. Use pharmacy reconciliation if available.
2. Mark changes
Flag: * = NEW, Δ = CHANGED dose/frequency, ✕ = STOPPED. Explain WHY for each change.
3. Teach-back
Review each changed med with patient. "Tell me how you'll take this at home." Low health literacy = use plain language.
4. Access check
Can patient afford meds? Has pharmacy? Need prior auth? Provide 30-day bridge if insurance gap.
⚡ Summary
Summary
Readmission Is Usually a Discharge Failure
A 30-day readmission is more often a failure of the discharge process than of the disease.Four pillars: medication reconciliation, follow-up, patient education, and safety-net instructions. Plan the discharge from the day of admission rather than on the morning it happens.
Medication Reconciliation Is the Number One Safety Issue
Compare the discharge list against the true pre-admission list, drug by drug.Explicitly account for every change: what was started, stopped, dose-changed, and what was held in hospital and must be restarted. Drugs held for an inpatient reason and never restarted, and inpatient-only drugs continued at home, are the two classic errors.
Name the Follow-Up, Do Not Just Recommend It
An appointment with a date, a time and a named clinician.Within 7 days for heart failure and other high-risk conditions, within 2 weeks otherwise.'Follow up with your PCP' is not a plan, and the patients least able to arrange it themselves are the ones most likely to bounce back.
Close the Test Loop
List every pending result and name who will follow it up.Pending cultures, biopsies and incidental imaging findings are routinely lost at discharge, because the inpatient team stops looking and the outpatient team never knew. Put them in the summary and in the follow-up appointment note.
Teach Back, Do Not Just Hand Over
Ask the patient to explain the plan in their own words. Cover what changed and why, what to watch for, what to do about it, and how to take each new medication. Written instructions at an appropriate reading level, in the patient's language, and involve the caregiver who will actually be managing it.
Give an Explicit Safety Net
Specific red-flag symptoms with a specific action and a specific number to call.'Come back if you feel worse' is not actionable: name the weight gain, the shortness of breath, the fever, the pain, the bleeding, so the patient knows which change matters.
Identify the High-Risk Discharge
Heart failure, COPD, cirrhosis, recent readmission, polypharmacy, cognitive impairment, poor social support, homelessness, substance use disorder, low health literacy, and no primary care clinician.These need earlier and more intensive planning: case management, home health, a pharmacist review, and a follow-up phone call within 48 to 72 h.
Write the Summary for the Person Who Will Read It
Use I-PASS or an equivalent structure and get the summary out the same day.State the discharge diagnosis, what happened, what changed, what is pending, and what the receiving clinician must do.Also confirm the practical prerequisites: transport, whether the prescriptions are affordable and actually obtainable, equipment at home, and whether the patient can safely manage stairs and self-care.
🔍 Overview
Overview
~20% of patients have adverse events within 3 weeks of discharge. ~40% involve medication errors. I-PASS handoff, bedside med reconciliation, teach-back, and 48h phone calls reduce readmissions.
📋 On Rounds
Pimp Questions
What is the single most commonly missed item on a discharge that leads to readmission?
Medication reconciliation -specifically, not communicating medication changes to the patient and PCP. Studies show that ~50% of patients have at least one medication discrepancy at discharge. The most dangerous errors: (1) restarting a medication that was intentionally stopped (e.g., metformin held for AKI, ACEi held for hyperkalemia), (2) not starting a new medication that was added (e.g., DAPT after stent, anticoagulation after new AFib)
When should follow-up be within 48–72 hours vs 7–14 days after discharge?
48–72 hour follow-up is indicated for high-risk discharges: heart failure (weight monitoring, diuretic adjustment), COPD exacerbation (inhaler reassessment), AKI (Cr recheck), medication changes requiring monitoring (new anticoagulation, new insulin), patients with limited health literacy or social support, and any patient you're worried about.
What is the I-PASS framework and why does it reduce medical errors?
I-PASS is a standardized handoff mnemonic that reduced medical errors by 30% in a multicenter study I-PASS Study, 2014. I = Illness severity (stable, watcher, unstable). P = Patient summary (one-liner: age, sex, diagnosis, key hospital course). A = Action list (what needs to be done overnight -labs to check, meds to give, pending results). S = Situation awareness ("if X happens, then do Y" -anticipatory guidance).
What are the most common causes of 30-day readmission and how do you prevent them?
The top 3: (1) Heart failure (highest readmission rate ~25%) -prevent with: weight monitoring daily at home, clear diuretic instructions ("if weight up 3 lbs in 1 day, take extra Lasix"), follow-up within 48-72h, dietary counseling (2g Na restriction). (2) COPD -prevent with: proper inhaler technique verified at discharge, action plan for exacerbations, pulm rehab referral, 5-7 day follow-up.
Clinical Examples
📋 Case 1, Heart Failure Discharge with High Readmission Risk
Patient: 72M with HFrEF (EF 25%), admitted for acute decompensation (fluid overload). Now euvolemic on furosemide 80 mg PO BID. Lives alone, limited health literacy. Eats canned soups daily.
Key findings: HF is the #1 readmission diagnosis (~25% 30-day readmission rate). High-risk features: lives alone, limited literacy, dietary non-adherence. Most HF readmissions are from volume overload due to dietary indiscretion or medication non-compliance.
Management:
Teach-back method: "Tell me in your own words when you should call your doctor" (verifies comprehension)
Daily weight instructions: "Weigh yourself every morning after using the bathroom. If you gain 3 lbs in 1 day or 5 lbs in 1 week, take an extra Lasix AND call us"
Follow-up within 48-72h (HF clinic or PCP). Transitional care nurse phone call within 48h
Medication reconciliation at bedside with patient: review each med, what it's for, when to take it
Teaching point: The discharge summary is a medical document, the discharge CONVERSATION is what prevents readmissions. Teach-back is more valuable than any written instruction. If a patient can't explain their weight monitoring plan back to you, they're not ready for discharge.
📋 Case 2, Complex Med Reconciliation After ACS
Patient: 58M admitted for NSTEMI, underwent PCI with DES to LAD. Started on DAPT (ASA + ticagrelor), high-intensity statin, beta-blocker, ACEi. Home meds included clopidogrel (prior stroke), PPI, metformin. Multiple medication changes.
Key findings: High-complexity medication reconciliation: new DAPT (replacing prior clopidogrel monotherapy), new statin dose, new BB and ACEi. Risk: patient may continue old clopidogrel + new ticagrelor (double P2Y12), or stop ASA thinking it's redundant.
Management:
Create a clean medication list with "STOP" and "NEW" clearly marked
STOP: clopidogrel (replaced by ticagrelor). CONTINUE: ASA 81 mg (part of DAPT)
PPI: continue (GI prophylaxis on DAPT). Note: omeprazole interacts with clopidogrel but NOT ticagrelor
Cardiology follow-up within 1-2 weeks. Emphasize: do NOT stop ticagrelor or ASA without calling cardiologist
Teaching point: Post-PCI patients who stop DAPT prematurely have a 5-10% risk of stent thrombosis (often fatal STEMI). The discharge conversation must include: "Do not stop these two blood thinners for ANY reason without calling your cardiologist first, not even for a dental cleaning."
📋 Case 3, Safe Opioid Tapering at Discharge
Patient: 45F admitted for pancreatitis × 7 days, received IV hydromorphone for pain control. Now tolerating PO, pain 3/10. Team wants to transition to oral and prepare for discharge. Patient has no prior opioid use.
Key findings: Opioid-naive patient on IV opioids × 7 days, at risk for physical dependence and outpatient opioid misuse. Must taper appropriately and set clear expectations for discharge prescribing.
Management:
Convert IV hydromorphone to oral equivalent (2 mg IV hydromorphone ≈ 8 mg PO hydromorphone)
Reduce by 25-50% when converting IV → PO (incomplete cross-tolerance)
Discharge with 3-5 day supply of oral opioid MAXIMUM with no refills (short-course prescribing)
Co-prescribe: acetaminophen 1g TID + ibuprofen 400 mg TID (multimodal, reduces opioid need by 30-40%)
Set expectations: "Pain should improve daily. If it's getting worse rather than better, call us, that's not normal"
Teaching point: The #1 risk factor for chronic opioid use is the initial prescription length. Prescribing > 7 days of opioids for acute pain doubles the risk of chronic use at 1 year. Always prescribe the minimum effective course with a clear taper plan.
📣 Sample Presentation
One-Liner
"Mrs. Baker is a 74-year-old admitted 4 days ago for COPD exacerbation, now back to baseline on home O₂ (2L), tolerating PO steroids, and able to ambulate. Ready for discharge."
Key Points to Cover on Rounds
Discharge medications reviewed at bedside: * NEW: prednisone 40 mg PO daily × 3 more days (5-day course total), * NEW: azithromycin 250 mg daily × 2 more days, * CHANGED: added Breo Ellipta 200/25 daily (was not on ICS/LABA before). Home meds continued: tiotropium, albuterol PRN, lisinopril, atorvastatin. Follow-up: PCP in 5 days, pulmonology in 2 weeks. Smoking cessation: quit 2 years ago -reinforced. Pulm rehab referral sent. Patient taught proper inhaler technique (observed return demo). Red flags reviewed: return if worsening dyspnea, fever, or unable to complete steroid taper.
Pre-Discharge Checklist -Discharge Planning
Domain
Checklist Item
Action / Details
Medication reconciliation
Complete and reviewed at bedside
Compare admission → discharge meds. Mark NEW / CHANGED / STOPPED. Ensure patient understands each change and why. Verify meds are affordable and filled.
Follow-up appointments
Scheduled before discharge
PCP within 7–14 days (48–72h if high-risk: HF, ACS, COPD). Specialist follow-up as needed with date and location confirmed. Patient has written appointment details.
Patient education
Red flags and return precautions
Disease-specific return precautions explained in plain language. Teach-back method: patient explains warning signs in their own words. Written instructions provided.
Discharge summary
Completed and sent to PCP
Sent same day. Include: admission diagnosis, hospital course, key results, medication changes with rationale, pending results, follow-up plan, code status.
Pending labs/results
Responsible provider assigned
Every pending result (blood cultures, pathology, imaging reads) must have a named provider responsible for follow-up. Document who will contact the patient.
VTE prophylaxis
Post-discharge plan if applicable
Extended prophylaxis for: post-major orthopedic surgery (35 days), post-cancer surgery (28 days). Ensure prescription and patient education on injection technique if applicable.
Code status
Confirmed and documented
Especially for patients with serious illness, recurrent admissions, or goals-of-care discussions during hospitalization. Ensure advance directive is in the chart.
Post-Discharge Monitoring Plan
Timeframe
Action
24–48 hours
Post-discharge phone call (nursing or pharmacy). Confirm: meds filled, understanding discharge instructions, no new symptoms.
48–72 hours
High-risk follow-up: HF (weight, diuretic response), AKI (Cr recheck), new anticoag (INR if warfarin), new insulin (glucose log).
7 days
PCP follow-up for most patients. Review hospital course, pending results, medication changes.
30 days
Specialist follow-up. Labs (Cr, CBC, LFTs as indicated). Functional status assessment.
Readmission within 30 days is often a failure of discharge, not disease. The most impactful interventions: medication reconciliation at bedside (not just on paper), confirmed follow-up appointment (not just "follow up with PCP"), and post-discharge phone call within 48h.
RoundsRx Infographic Series · #187 · General Medicine · PDF 137 KB
Text version
Transitions of Care · One Pager
Safe Discharge
I-PASS handoff. Med reconciliation at bedside. Teach-back method. Follow-up within 7 days. Phone call at 48h. Red flag instructions in writing.
🧪 I-PASS
Illness severity → Patient summary → Action list → Situation awareness ("if X, then Y") → Synthesis by receiver. Reduces errors 30% I-PASS Study, 2014.
🚨 Medication Safety
Reconcile at bedside: every med reviewed (new, changed, stopped + reason). Teach-back: patient explains each med. Ensure meds IN HAND (not just prescriptions).
💊 Prevent Readmission
Phone call within 48h. Follow-up within 7d (48-72h for HF). Specific return precautions in writing. Address social barriers: transport, cost, health literacy.
💊 Key Drugs
EnsurePatient has medications in hand
ReconcileEvery med -new, changed, stopped
Follow-upPCP within 7d, HF within 48-72h
CallPost-discharge phone call at 48h
⚠️ Pitfalls
Med reconciliation by chart review only (must be at bedside with patient)
Discharge summary not sent to PCP same day
No specific return precautions given
Pending results not handed off to outpatient provider
Rotation
General Wards
The bread and butter of internal medicine. Common inpatient diagnoses, admission workups, discharge planning, and transitions of care.
Pathologic activation of coagulation → widespread microvascular thrombosis → consumption of factors and platelets → paradoxical bleeding. Never primary -always find and treat the trigger.
🔍 Overview
Lab Pattern
Lab
Finding
Why
Platelets
↓↓
Consumed in microthrombi ISTH DIC Score, Taylor 2001
Treat the underlying cause. DIC is ALWAYS secondary -sepsis, malignancy, obstetric emergency, trauma. Transfusion supports hemostasis but does not fix the driver.
Product
Indication
Dose
Target
Platelets
Plt <10K (any) or <50K with active bleeding
1 apheresis unit or 6-pack
Plt >50K if bleeding, >10K if stable
Cryoprecipitate
Fibrinogen <100-150 mg/dL
10 units (pools)
Fibrinogen >150 mg/dL. Each pool raises fibrinogen ~50 mg/dL.
FFP
PT/aPTT >1.5× normal WITH active bleeding
15 mL/kg (typically 4 units)
INR <1.5. Replaces all clotting factors.
pRBCs
Hgb <7 (or <8 if active hemorrhage)
Per transfusion protocol
Hemodynamic stability, adequate oxygen delivery.
Heparin SELECT CASES
Chronic/compensated DIC with thrombosis predominance
Low-dose UFH or prophylactic LMWH
Only when thrombosis outweighs bleeding risk (e.g., Trousseau syndrome, purpura fulminans). Contraindicated in acute DIC with active hemorrhage.
Tranexamic acid
Hyperfibrinolysis-predominant DIC
1g IV load then 1g over 8h
Consider in APL-associated DIC or trauma. Use with caution -can worsen microvascular thrombosis.
Do NOT transfuse to normalize labs. Transfuse ONLY if actively bleeding or at high risk of bleeding (pre-procedure). Prophylactic transfusion in stable DIC is not indicated and wastes blood products.
📋 On Rounds
How does DIC differ from TTP on labs?
Both: thrombocytopenia + schistocytes. DIC = ↑ PT/INR, ↑ aPTT, ↓ fibrinogen, ↑↑ D-dimer (consumptive coagulopathy). TTP = PT/INR and aPTT are NORMAL, fibrinogen is NORMAL. TTP is platelet consumption only -the coagulation cascade is not activated. If coags are deranged → DIC. If coags are normal → TTP/HUS.
How do you differentiate DIC from TTP? Both have MAHA + thrombocytopenia.
DIC = prolonged PT/INR + low fibrinogen + very high D-dimer. The coagulation cascade is consumed → bleeding predominates. TTP = normal PT/INR + normal fibrinogen + ADAMTS13 < 10%. The problem is platelet microthrombi, not coagulation factor consumption. The key lab: fibrinogen. Low fibrinogen = DIC. Normal fibrinogen = think TTP (or HUS). This distinction is critical because platelet transfusion is treatment in DIC (if bleeding)
What lab value is the most specific for DIC, and why?
Fibrinogen is the most specific and clinically actionable lab. In DIC, the coagulation cascade is massively activated → clotting factors AND fibrinogen are consumed. Low fibrinogen (< 100-150 mg/dL) is highly specific for DIC -it differentiates DIC from other causes of thrombocytopenia + coagulopathy (TTP has normal fibrinogen, liver disease has low fibrinogen but less severely, heparin-induced doesn't affect fibrinogen).
How do you differentiate DIC from severe liver disease?
Both have elevated PT/INR, low platelets, and low fibrinogen -making differentiation challenging. Key differentiators: (1) D-dimer: massively elevated in DIC (> 10× ULN), only mildly elevated in liver disease. (2) Factor VIII: LOW in DIC (consumed like all factors), ELEVATED in liver disease (factor VIII is made by endothelium, not hepatocytes -actually increases in liver disease as an acute phase reactant).
Clinical Examples
📋 Case 1, Sepsis-Induced DIC with Active Bleeding
Patient: 65M with septic shock from E. coli urosepsis. Developing diffuse oozing from IV sites, petechiae, and hematuria.
Treat the underlying cause, antibiotics + source control (this is the ONLY curative treatment)
Cryoprecipitate 10 units for fibrinogen < 100 (each unit raises fibrinogen ~5-10 mg/dL)
Platelet transfusion for plt < 50K + active bleeding
FFP 4 units for prolonged INR + active bleeding
Trend fibrinogen, plt, INR q4-6h, fibrinogen is the key lab to follow
Do NOT give heparin (bleeding-predominant DIC)
Teaching point: Fibrinogen is the most specific and actionable lab in DIC. Factor VIII is LOW in DIC but ELEVATED in liver disease, this is the single best lab to differentiate them when the clinical picture is unclear.
📋 Case 2, DIC in APL (Thrombotic Predominant)
Patient: 32F presenting with pancytopenia and gum bleeding. Peripheral smear: blasts with Auer rods. Diagnosed with acute promyelocytic leukemia (APL). Labs: plt 18K, INR 1.8, fibrinogen 85, D-dimer 12,000.
Key findings: APL-associated DIC, unique because it has both bleeding AND thrombotic features. APL blasts release tissue factor and annexin II causing consumptive coagulopathy.
Management:
Start ATRA (all-trans retinoic acid) immediately, do not wait for confirmatory testing
Cryoprecipitate and platelet transfusions as needed
Hematology/oncology emergent consult
DIC typically resolves within 48-72h of ATRA initiation
Teaching point: APL is a hematologic emergency because of severe DIC. ATRA corrects the DIC by inducing differentiation of the leukemic promyelocytes. In APL, maintain higher fibrinogen (> 150) and platelet (> 50K) thresholds than typical DIC.
📋 Case 3, DIC vs TTP Differentiation
Patient: 44F with thrombocytopenia (plt 22K), schistocytes on smear, and elevated LDH. Presenting with confusion and fever. Is this DIC or TTP?
Key findings: PT/INR NORMAL. Fibrinogen 310 (NORMAL). D-dimer mildly elevated. Cr 2.1. This is NOT DIC, normal coags with thrombocytopenia + MAHA = TTP until proven otherwise.
Management:
Send ADAMTS13 activity level URGENTLY (do not wait for result to treat)
Do NOT transfuse platelets in TTP (fuels thrombosis, "adding fuel to fire")
Start steroids (methylprednisolone 1 g/day x 3 days)
Consult hematology emergently
Teaching point: The key differentiator: DIC = prolonged PT/INR + low fibrinogen + very high D-dimer. TTP = NORMAL PT/INR + NORMAL fibrinogen. Both have MAHA + thrombocytopenia. If coags are normal, think TTP. Platelet transfusion is treatment in DIC but contraindicated in TTP.
📣 Sample Presentation
One-Liner
"Mr. Ahmed is a 62-year-old with septic shock from cholangitis who developed diffuse oozing from line sites, petechiae, and hematuria. Platelets 32K, INR 2.8, fibrinogen 68, D-dimer >20,000. Consistent with acute DIC."
Key Points to Cover on Rounds
DIC secondary to sepsis (cholangitis -source controlled with ERCP yesterday). Labs: plt 32K, INR 2.8, fibrinogen 68 (<100 → cryoprecipitate 10 units given), D-dimer >20K. Actively bleeding from lines. Treatment: (1) treat underlying cause (antibiotics day 3, source controlled), (2) cryoprecipitate for fibrinogen <100, (3) platelets transfused (plt <50 + active bleeding), (4) FFP 4 units for INR 2.8 + active bleeding. NOT giving heparin (bleeding-predominant DIC). Plan: trend fibrinogen, plt, INR q6h, continue treating sepsis.
IV sites, surgical sites, mucosal bleeding, petechiae, hematuria, GI bleeding. Simultaneous bleeding AND thrombosis is pathognomonic.
Thrombotic complications
Each assessment
Skin necrosis (purpura fulminans), acral ischemia, organ dysfunction (renal, hepatic). DVT/PE screening if clinical concern.
⚡ Summary
Summary
The Paradox That Defines It
Pathologic activation of coagulation causes widespread microvascular thrombosis, which consumes clotting factors and platelets, so the patient bleeds.Thrombosis and hemorrhage are happening at the same time, which is why the labs look like a bleeding disorder while the pathology is clotting.
Read the Lab Pattern
Platelets low (consumed in microthrombi), fibrinogen low with below 100 mg/dL indicating severe disease, PT and aPTT prolonged, D-dimer markedly raised, and schistocytes on the smear from red cells sheared through fibrin strands. Fibrinogen is the most specific marker of severity, and because it is an acute phase reactant a 'normal' value in a septic patient may already represent a large fall.
Trend the Labs, Do Not Read Them Once
A single set can look unremarkable early.A falling platelet count and a falling fibrinogen over hours are more informative than any absolute value, and the ISTH DIC score is designed to be applied serially rather than as a one-off.
DIC Is Never Primary
Always find and treat the trigger, because DIC will not resolve until it is removed.Sepsis is the commonest, about 35%, then trauma and major surgery, malignancy (acute promyelocytic leukemia and mucin-secreting adenocarcinomas of pancreas and prostate), obstetric emergencies (abruption, amniotic fluid embolism, HELLP), massive transfusion, large aortic aneurysm and envenomation.
Do Not Transfuse to Normalize Numbers
Transfuse only for active bleeding or before a procedure with high bleeding risk.Prophylactic transfusion in a stable DIC patient is not indicated, wastes product and adds transfusion risk without changing outcomes. The abnormal numbers are a marker of the underlying illness, not a target.
Know What to Give When They Do Bleed
Platelets for a count below about 50,000 with bleeding.Cryoprecipitate for fibrinogen below 100 to 150, which is the most efficient way to replace it. Fresh frozen plasma for a prolonged PT or aPTT with bleeding. Follow the response with repeat labs rather than giving fixed volumes.
Heparin Is Only for the Thrombotic Phenotype
Consider low-dose heparin when thrombosis dominates: purpura fulminans, digital ischemia, large vessel thrombosis, or chronic compensated DIC in malignancy. Avoid it when bleeding dominates, and be aware that antithrombin depletion in DIC blunts its effect. Antifibrinolytics such as tranexamic acid are generally contraindicated, since blocking fibrinolysis in a microthrombotic state worsens organ ischemia.
APL Is the Exception Worth Knowing
Acute promyelocytic leukemia causes a catastrophic DIC with early fatal hemorrhage, and ATRA started on clinical suspicion reverses it.Support aggressively while it takes effect: keep fibrinogen above 150 and platelets above 50,000, which are higher thresholds than in ordinary DIC precisely because intracranial hemorrhage is what kills these otherwise curable patients.
Thrombotic microangiopathies -ADAMTS13 deficiency (TTP) or complement-mediated (aHUS). Thrombocytopenia + MAHA + organ damage with NORMAL coags. Untreated TTP mortality > 90%. Plasma exchange saves lives. Never transfuse platelets.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Hemolysis (retic > 2.5%, hapto undetectable, or indirect bili > 2)
A
No active cancer
S
No stem cell/organ transplant
M
MCV < 90
I
INR < 1.5
C
Creatinine < 2.0
≥ 5: high probability → start plasma exchange. Don't wait for ADAMTS13 results.
🚨 Management
Plasma exchange
Daily TPE until platelets > 150K × 2 days. Removes antibodies + ultra-large vWF, replaces ADAMTS13. FFP as bridge if TPE delayed.
Steroids
Methylprednisolone 1g IV × 3 days → prednisone 1 mg/kg. Rituximab if refractory/relapsing.
Caplacizumab
Anti-vWF nanobody.HERCULES, 2019: 74% reduction in death + recurrence. Now standard alongside TPE + steroids.
NEVER transfuse platelets in TTP
🧪 Workup
Workup
CBC + peripheral smear -severe thrombocytopenia (often < 30K) + schistocytes. Schistocytes are REQUIRED for diagnosis.
ADAMTS13 activity level -send immediately but do NOT wait for results to start PLEX. ADAMTS13 < 10% = TTP. Takes 2-5 days to result. ADAMTS13 Discovery Study, 2004
PLASMIC score -7-variable clinical prediction score. Score 6-7 = high probability of ADAMTS13 < 10% → start PLEX empirically. Components: platelet count < 30K, hemolysis (retic > 2.5%, haptoglobin undetectable, indirect bili > 2), no active cancer, no transplant, MCV < 90, INR < 1.5, Cr < 2. PLASMIC Score Derivation, 2017
LDH -markedly elevated (often > 1000). Trends with disease activity -single best marker to follow during treatment.
Haptoglobin -undetectable (consumed by free hemoglobin binding)
Reticulocyte count -elevated (bone marrow compensating for hemolysis)
Indirect bilirubin -elevated (hemolysis)
Fibrinogen -NORMAL in TTP. This is the key differentiator from DIC (where fibrinogen is low). If fibrinogen is low, reconsider DIC.
Direct Coombs (DAT) -negative. Rules out autoimmune hemolytic anemia.
Cr -mild elevation typical. If Cr markedly elevated (> 3), consider HUS over TTP (renal-dominant TMA).
Coags (PT/INR) -should be normal. If elevated → think DIC, not TTP.
💊 Medications
Medications
Drug
Dose
Route
Notes
Therapeutic plasma exchange (PLEX)
1-1.5 plasma volumes daily
Apheresis
Cornerstone of treatment. Removes anti-ADAMTS13 antibodies and ultra-large vWF multimers, replaces ADAMTS13. Continue daily until platelet count > 150K × 2 consecutive days, then taper. Canadian TTP PLEX Trial, 1991
Methylprednisolone
1g IV daily × 3 days
IV
Then transition to prednisone 1 mg/kg daily with taper. Immunosuppression to reduce anti-ADAMTS13 antibody production.
Caplacizumab
11 mg IV first dose → 11 mg SQ daily
IV/SQ
Anti-vWF nanobody -prevents platelet-vWF binding. 74% reduction in composite of death + recurrence + major thromboembolic event.HERCULES, 2019. Continue for 30 days after last PLEX. Monitor for bleeding (mucocutaneous).
Rituximab
375 mg/m² IV weekly × 4 doses
IV
For refractory TTP (no response after 5-7 days PLEX) or relapsing TTP. Depletes anti-ADAMTS13-producing B cells. Response in 1-3 weeks. Increasingly used upfront in severe cases.
DO NOT give platelets
-
-
CONTRAINDICATED (unless life-threatening hemorrhage). Transfused platelets are consumed by ultra-large vWF multimers → fuels microthrombosis → clinical deterioration. "Adding fuel to the fire."
Folate
1 mg daily
PO
Support RBC production during ongoing hemolysis.
📋 On Rounds
Why are platelets contraindicated in TTP?
Ultra-large vWF multimers (uncleaved by absent ADAMTS13) create a thrombotic environment. Transfused platelets bind immediately → more microthrombi → worsened organ ischemia. The platelet count may be 5,000 but the patient is at risk from thrombosis, not bleeding. Treatment = remove the cause (plasma exchange), not add substrate (platelets).
Why should you NEVER transfuse platelets in TTP?
In TTP, platelet microthrombi are the pathology -transfusing platelets is like adding fuel to a fire. The ultra-large vWF multimers (from ADAMTS13 deficiency) recruit and consume platelets into microthrombi in small vessels, causing ischemic organ damage (brain, kidneys). Adding more platelets → more substrate for thrombus formation → worse organ damage.
What is caplacizumab and why was it a breakthrough for TTP?
Caplacizumab is an anti-von Willebrand factor nanobody that blocks the interaction between ultra-large vWF multimers and platelets → prevents platelet adhesion and microthrombus formation. HERCULES, 2019: caplacizumab + standard therapy (PLEX + steroids) vs placebo: faster platelet normalization, fewer thromboembolic events, fewer TTP-related deaths. Dose: 11 mg IV before first PLEX, then 11 mg SQ daily until 30 days after last PLEX.
What is the PLASMIC score and how does it guide your decision to start PLEX?
PLASMIC score predicts ADAMTS13 < 10% (which confirms TTP). Components: Platelet count < 30K (+1), combined hemolysis variables (reticulocyte > 2.5%, haptoglobin undetectable, indirect bilirubin > 2) (+1), no active cancer (+1), no solid organ or stem cell transplant (+1), MCV < 90 (+1), INR < 1.5 (+1), Cr < 2.0 (+1). Score 0-4: low probability TTP → consider other MAHA causes (DIC, HUS).
❓ What is the classic pentad of TTP and how often is it complete?
The classic pentad: (1) thrombocytopenia, (2) microangiopathic hemolytic anemia (schistocytes), (3) neurological symptoms, (4) renal impairment, (5) fever. However, the full pentad is present in < 5% of cases. Most present with only thrombocytopenia + MAHA. Waiting for the pentad delays treatment and increases mortality. Treat on clinical suspicion.
❓ What is ADAMTS13 and why is it deficient in TTP?
ADAMTS13 is a metalloprotease that cleaves ultra-large von Willebrand factor (vWF) multimers into smaller fragments. In immune TTP, autoantibodies against ADAMTS13 cause acquired deficiency (< 10% activity). Without ADAMTS13, ultra-large vWF multimers accumulate → spontaneous platelet aggregation → microvascular thrombosis throughout the body. Congenital TTP (Upshaw-Schulman) is genetic ADAMTS13 deficiency.
❓ Why are platelets contraindicated in TTP?
Transfused platelets are immediately consumed by the ultra-large vWF multimers that are pathologically accumulated in the microvasculature. This fuels more microthrombosis rather than raising the platelet count -"adding fuel to the fire." Only give platelets if there is life-threatening hemorrhage (which is rare in TTP because the thrombocytopenia is consumptive, not due to production failure).
❓ When would you give rituximab in TTP?
Refractory TTP (no response after 5-7 days of daily PLEX), relapsing TTP, or preemptive treatment when ADAMTS13 falls < 10% during remission monitoring (before clinical relapse). Some centers use rituximab upfront in severe presentations. Rituximab depletes the B cells producing anti-ADAMTS13 antibodies. Response in 1-3 weeks. TTP Rituximab Study, 2011
Key findings: Microangiopathic hemolytic anemia (MAHA) + thrombocytopenia = TMA. High PLASMIC score (> 5) = high probability of TTP (ADAMTS13 < 10%). Do NOT wait for ADAMTS13 result to start treatment.
Management:
Send ADAMTS13 activity + inhibitor BEFORE starting PLEX (plasma dilutes the sample)
Emergent therapeutic plasma exchange (PLEX), daily until platelets > 150K × 2 days
Caplacizumab 11 mg IV bolus before first PLEX → 11 mg SQ daily (anti-vWF nanobody, faster platelet recovery) HERCULES, 2019
Do NOT transfuse platelets (fuels microvascular thrombosis, "adding fuel to the fire")
Teaching point: TTP is a clinical emergency, mortality untreated is > 90%. Start PLEX empirically based on PLASMIC score. Platelet transfusion is contraindicated unless life-threatening bleeding, it worsens microvascular thrombosis.
📋 Case 2, TTP vs HUS Differentiation
Patient: 4-year-old boy with bloody diarrhea × 5 days after eating undercooked hamburger. Now oliguric, pallor. Hgb 6.8, platelets 28K, Cr 4.8, LDH 920. Smear: schistocytes. Stool: Shiga toxin positive.
Key findings: Typical HUS (Shiga toxin-associated): MAHA + thrombocytopenia + AKI after bloody diarrhea with Shiga toxin-producing E. coli (usually O157:H7). Renal involvement is predominant (unlike TTP where neuro predominates).
Management:
Supportive care is mainstay, NO antibiotics (may increase Shiga toxin release and worsen HUS)
IVF resuscitation, monitor UOP strictly, dialysis if needed for renal failure
Transfuse pRBCs for symptomatic anemia (unlike TTP, platelet transfusion is not as clearly contraindicated)
PLEX is NOT standard for typical HUS (unlike TTP)
Most children recover renal function (90%+), but 5-10% develop ESRD
Teaching point: The key differentiator: TTP = neurologic predominance + ADAMTS13 < 10%. HUS = renal predominance + Shiga toxin + normal ADAMTS13. Atypical HUS (complement-mediated, no diarrhea) is treated with eculizumab (anti-C5).
📋 Case 3, Relapsing TTP with ADAMTS13 Monitoring
Patient: 42F with history of TTP 18 months ago (achieved remission with PLEX + steroids). Routine ADAMTS13 monitoring: activity dropped from 45% → 8% over 3 months. Asymptomatic, platelets 180K, LDH normal.
Key findings: Falling ADAMTS13 without clinical relapse, "subclinical relapse." ADAMTS13 < 10% predicts imminent clinical relapse with MAHA, thrombocytopenia, and end-organ damage.
Management:
Preemptive rituximab 375 mg/m² weekly × 4 (prevent clinical relapse before it occurs)
Monitor ADAMTS13 q2 weeks during rituximab treatment, expect recovery to > 20% within 4-8 weeks
Continue ADAMTS13 monitoring q3 months indefinitely (relapse risk is lifelong)
No PLEX needed if asymptomatic with normal counts, rituximab alone is sufficient preemptively
Caplacizumab course (30 days after PLEX) reduces relapse rate in the initial treatment period
Teaching point: ADAMTS13 monitoring after TTP allows preemptive treatment before clinical relapse. A falling ADAMTS13 < 10% is an actionable finding, rituximab at this point prevents the life-threatening clinical episode. This is why lifelong monitoring is essential.
📣 Sample Presentation
One-Liner
"Ms. Wilson is a 36-year-old presenting with confusion, petechiae, Hgb 7.8, platelets 12K, Cr 1.8, LDH 1,400, and schistocytes on peripheral smear. PLASMIC score 7. ADAMTS13 sent."
Key Points to Cover on Rounds
MAHA + severe thrombocytopenia + neuro symptoms + renal impairment -TTP until proven otherwise. PLASMIC 7 (high probability). ADAMTS13 sent -don't wait for result. Treatment initiated emergently: (1) PLEX (plasmapheresis) -first session today, (2) methylprednisolone 1g IV daily × 3 days, (3) caplacizumab 11 mg IV then SQ daily HERCULES, 2019. Platelets NOT transfused (contraindicated -fuels thrombosis). Hgb 7.8 → transfuse pRBCs (safe, not platelets). Plan: daily PLEX until plt >150 × 2 days, ADAMTS13 pending.
Monitoring
Platelet count daily -primary response marker. Goal: > 150K × 2 consecutive days before stopping/tapering PLEX. If platelets plateau or drop during taper → resume daily PLEX.
LDH daily -should trend down with effective treatment. Persistent elevation despite rising platelets → consider ongoing hemolysis or alternate diagnosis.
Schistocytes -should decrease on serial peripheral smears. Request daily smear during active treatment.
ADAMTS13 activity -send at diagnosis. Recheck after PLEX completion. Monitor for relapse (ADAMTS13 < 10% even in remission = high relapse risk → consider preemptive rituximab).
Cr + UA -renal function. Improving Cr supports treatment response.
Neuro exam -focal deficits, confusion, seizures. Fluctuating neuro symptoms are classic for TTP. Should improve with PLEX.
Haptoglobin + indirect bilirubin -hemolysis resolution markers. Haptoglobin should recover as hemolysis resolves.
Bleeding assessment -especially while on caplacizumab (mucocutaneous bleeding risk). Check for gum bleeding, epistaxis, GI bleed.
Long-term follow-up -ADAMTS13 levels q3-6 months for 2+ years. Relapse rate ~30-50% in immune TTP. Preemptive rituximab if ADAMTS13 drops < 10%.
⚡ Summary
Summary
The Pentad Is Historical; Two Findings Are Enough
Thrombocytopenia plus microangiopathic hemolytic anemia with schistocytes, and normal coagulation studies.Waiting for the classic pentad, adding fever, renal failure and neurologic change, means waiting until the patient is dying: the full pentad appears in a small minority. Normal PT and PTT are what separate it from DIC.
Untreated Mortality Exceeds 90%
Plasma exchange reduces it to about 10 to 20%, which is one of the largest treatment effects in medicine. Start plasma exchange urgently on clinical suspicion; do not wait for the ADAMTS13 result, which is a send-out. Give plasma infusion as a stopgap if exchange cannot be started immediately.
Never Transfuse Platelets
Platelets fuel further microthrombosis and can precipitate stroke and myocardial infarction.Reserve them for life-threatening bleeding only, and remember that the thrombocytopenia in TTP is consumptive, so the count is a marker of disease activity rather than a transfusion trigger.
Use PLASMIC to Decide Fast
It predicts severe ADAMTS13 deficiency below 10% from data you already have: platelet count, hemolysis markers, absence of active cancer, no transplant, MCV, INR and creatinine. A high score justifies starting exchange before the assay returns, and a low score should prompt you to look hard for an alternative microangiopathy.
Separate the Three Microangiopathies
TTP: ADAMTS13 below 10%, ultra-large von Willebrand multimers, neurologic features predominate.Typical HUS: Shiga toxin from E. coli O157:H7, bloody diarrhea and renal failure, mostly children, and largely supportive care.Atypical HUS: complement dysregulation, renal-predominant, treated with eculizumab, and it does not respond to plasma exchange.
Do Not Give Antibiotics in Shiga Toxin HUS
Antibiotics increase toxin release and the risk of developing HUS in E. coli O157:H7 infection. Management is supportive, with fluids, dialysis where needed, and avoiding antimotility agents, which also worsen it.
Add Immunosuppression to Exchange in TTP
Corticosteroids plus rituximab, because acquired TTP is autoantibody-mediated and exchange alone removes the antibody without stopping its production. Caplacizumab, an anti-von Willebrand nanobody, shortens time to platelet recovery and reduces exacerbations, at the cost of bleeding risk.
Track Platelets and Watch for Relapse
Platelet recovery is the marker of response, and exchange continues until the count is sustained normal for at least 2 days. Follow ADAMTS13 activity after remission: a falling level predicts relapse and can prompt preemptive rituximab. Relapse occurs in about a third, so patients need long-term follow-up rather than discharge to primary care, and drug-induced microangiopathy (quinine, gemcitabine, calcineurin inhibitors, VEGF inhibitors) should be excluded, since the treatment there is stopping the drug.
RoundsRx Infographic Series · #79 · Hematology · PDF 151 KB
Text version
Hematology · One Pager
TTP -Thrombotic Thrombocytopenic Purpura
MAHA + severe thrombocytopenia → start PLEX tonight. Don't wait for ADAMTS13. Don't transfuse platelets. Caplacizumab + steroids + PLEX = triple therapy.
🧪 Suspect When
MAHA (schistocytes on smear) + severe thrombocytopenia (< 30K) ± neuro symptoms ± renal impairment ± fever. PLASMIC score 6-7 = high probability → start PLEX.
🚨 Treatment -Triple Therapy
(1) PLEX daily (until plt > 150 × 2 days). (2) Methylprednisolone 1g IV × 3d. (3) Caplacizumab 11 mg IV then SQ daily HERCULES, 2019. Don't wait for ADAMTS13 result.
⚠️ Critical Rules
Do NOT transfuse platelets (fuels thrombosis -adding fuel to fire). DO transfuse pRBCs if needed (Hgb support is safe). TTP vs HUS: TTP = neuro-predominant, HUS = renal-predominant.
💊 Key Drugs
PLEXDaily until plt > 150 × 2d
Methylprednisolone1g IV daily × 3d
Caplacizumab11 mg IV then SQ daily
Rituximab375 mg/m² (refractory/relapsing)
⚠️ Pitfalls
Platelet transfusion (fuels microthrombosis)
Waiting for ADAMTS13 before starting PLEX
Not starting caplacizumab (reduces mortality)
Confusing with DIC (DIC has low fibrinogen, TTP has normal fibrinogen)
Laboratory TLS: ≥ 2 metabolic abnormalities within 3 days before or 7 days after chemo. Clinical TLS: lab TLS + organ damage (AKI, arrhythmia, seizure).
Lab
Direction
Mechanism
Danger
Potassium
↑↑
Released from lysed cells
Cardiac arrhythmia → VF → death. Most immediately lethal.
Phosphate
↑↑
Released from lysed cells
Binds calcium → calcium phosphate deposition in kidneys → AKI
Moderate risk: AML (high WBC > 100K), CLL treated with venetoclax
Lower risk: most solid tumors (rare but can occur with highly chemo-sensitive tumors)
🚨 Management
Prevention (Before Chemo)
Intervention
Dose
Notes
Aggressive IVF ALL PATIENTS
2–3 L/m²/day NS (goal UOP 2 mL/kg/hr)
Start 24–48h before chemo. Dilutes uric acid + phosphate. Most important prevention.
Allopurinol (Zyloprim) MODERATE RISK
300–600 mg PO daily
Prevents new uric acid formation (xanthine oxidase inhibitor). Does NOT break down existing uric acid. Start 1–2 days before chemo.
Rasburicase (Elitek) HIGH RISK
0.2 mg/kg IV × 1 dose (or fixed 3–6 mg)
Recombinant uricase -rapidly breaks down existing uric acid. Works within hours. Rasburicase TLS Trial, 2001CONTRAINDICATED in G6PD deficiency (hemolytic crisis -produces H₂O₂). Check G6PD before giving if possible. Falsely lowers uric acid if sample is not kept on ice.
Treatment of Established TLS
Hyperkalemia: treat per hyperkalemia protocol (calcium, insulin/glucose, patiromer (Veltassa)/Lokelma, dialysis if refractory)
Hyperphosphatemia: phosphate binders (sevelamer, aluminum hydroxide short-term), aggressive IVF, dialysis if severe
Hypocalcemia: only treat if symptomatic (seizures, tetany, QT prolongation). Do NOT aggressively replete calcium -it worsens calcium-phosphate precipitation in kidneys
Hyperuricemia: rasburicase (if not already given), aggressive IVF
LDH -reflects tumor cell lysis and disease burden. Markedly elevated LDH pre-chemo = high TLS risk.
Cr + BUN -AKI from uric acid crystallization in renal tubules (urate nephropathy) and calcium-phosphate precipitation.
ECG -critical. Hyperkalemia (peaked T waves, widened QRS → fatal arrhythmia) and hypocalcemia (QTc prolongation → torsades). Get ECG before and after each lab check.
Urine output -track hourly. Target ≥ 2 mL/kg/hr with aggressive hydration. Oliguria = urate nephropathy → may need dialysis.
G6PD level -check BEFORE giving rasburicase. Rasburicase causes severe hemolytic anemia in G6PD-deficient patients (hydrogen peroxide accumulation). Prevalence: ~10% in African American males.
Risk stratification: High risk = ALL, Burkitt lymphoma, DLBCL with bulky disease + high LDH, WBC > 100K in AML. Intermediate = most AML, CLL with high WBC. Low = most solid tumors, indolent lymphoma.
💊 Medications
Medications
Drug
Dose
Route
Notes
Rasburicase
0.2 mg/kg IV × 1 dose
IV
Treatment of established TLS -converts uric acid → allantoin (highly soluble) Rasburicase TLS Trial, 2001. Onset within hours. Contraindicated in G6PD deficiency (severe hemolysis). Must put blood sample on ice immediately (rasburicase degrades uric acid in tube → falsely low reading).
Allopurinol
300-600 mg PO daily (start 2-3 days before chemo)
PO
PROPHYLAXIS ONLY -does NOT treat established TLS. Xanthine oxidase inhibitor -prevents NEW uric acid formation but does not break down existing uric acid. Dose-reduce in CKD.
IV fluids (NS or D5W)
200-250 mL/hr (3 L/m²/day)
IV
Aggressive hydration is the foundation. Start 24-48h before chemo. Target UOP ≥ 2 mL/kg/hr. Promotes renal uric acid excretion + prevents crystal precipitation.
Sevelamer
800 mg PO TID with meals
PO
Phosphate binder for hyperphosphatemia. Avoid calcium-based binders (calcium carbonate, calcium acetate) -risk of CaPO₄ precipitation in tissues with already elevated PO₄ + Ca product.
Calcium gluconate
1-2g IV over 10-20 min
IV
ONLY for symptomatic hypocalcemia (seizures, tetany, QTc prolongation). Avoid routine correction -exogenous calcium + high PO₄ → tissue calcification.
Insulin + D50
10 units regular insulin + 25g dextrose
IV
For hyperkalemia. Intracellular potassium shift. Check glucose at 1h. Use alongside calcium gluconate for membrane stabilization if ECG changes.
Kayexalate or patiromer
15-30g PO or 8.4g PO
PO
GI potassium elimination for persistent hyperkalemia. Slow onset (hours). Not a substitute for insulin + calcium in acute setting.
📋 On Rounds
Why is rasburicase contraindicated in G6PD deficiency?
Rasburicase is a recombinant uricase that converts uric acid to allantoin. This reaction produces hydrogen peroxide (H₂O₂) as a byproduct. Normally, glutathione neutralizes H₂O₂. In G6PD deficiency, the pentose phosphate pathway cannot regenerate NADPH → cannot regenerate glutathione → H₂O₂ accumulates → oxidative hemolytic crisis (methemoglobinemia + hemolytic anemia). This is life-threatening. Screen for G6PD deficiency (quantitative assay) before giving rasburicase, especially in African, Mediterranean, and Southeast Asian patients. Use allopurinol or febuxostat instead.
Why is allopurinol NOT a treatment for established TLS?
Allopurinol is a xanthine oxidase inhibitor -it blocks the conversion of hypoxanthine → xanthine → uric acid. It prevents NEW uric acid formation but does NOT break down existing uric acid. In established TLS with already-elevated uric acid (e.g., UA = 14), you need rasburicase, which is a recombinant urate oxidase that directly converts existing uric acid → allantoin (soluble, easily excreted).
What electrolyte abnormality in TLS can you NOT aggressively correct and why?
Hypocalcemia -do NOT aggressively correct unless symptomatic (seizures, tetany, QTc prolongation with hemodynamic instability). In TLS, both calcium AND phosphate are abnormal: phosphate is very high from cell lysis, calcium drops because Ca²⁺ binds to the excess phosphate (calcium-phosphate precipitation).
❓ What are the Cairo-Bishop criteria for tumor lysis syndrome?
Laboratory TLS = 2 or more of: (1) uric acid ≥ 8 or 25% increase, (2) K⁺ ≥ 6 or 25% increase, (3) PO₄ ≥ 4.5 or 25% increase, (4) Ca²⁺ ≤ 7 or 25% decrease. Clinical TLS = lab TLS + ≥ 1 of: Cr ≥ 1.5× ULN, cardiac arrhythmia, seizure, or death. Clinical TLS is what kills patients.
❓ Why can you NOT give rasburicase to G6PD-deficient patients?
Rasburicase converts uric acid to allantoin via an oxidation reaction that produces hydrogen peroxide (H₂O₂) as a byproduct. G6PD-deficient patients cannot generate adequate NADPH to neutralize H₂O₂ → severe oxidative hemolytic anemia + methemoglobinemia. Prevalence of G6PD deficiency: ~10% of African American males, common in Mediterranean and Asian populations. Must check G6PD BEFORE rasburicase.
❓ Why do you avoid calcium-based phosphate binders in TLS?
In TLS, both phosphate and calcium levels are deranged. Giving calcium-based binders (calcium carbonate, calcium acetate) adds exogenous calcium. When the calcium × phosphate product exceeds 60, calcium-phosphate crystals precipitate in tissues -kidneys (worsening AKI), heart, lungs, and soft tissues (metastatic calcification). Use sevelamer (non-calcium binder) instead.
❓ What is the difference between allopurinol and rasburicase in TLS?
Allopurinol = prophylaxis only. Xanthine oxidase inhibitor -prevents NEW uric acid formation but does NOT reduce existing uric acid. Start 2-3 days before chemo. Rasburicase = treatment. Recombinant urate oxidase -directly converts existing uric acid → allantoin (1000× more soluble). Works within hours. For established TLS, rasburicase is vastly superior.
❓ Which malignancies are highest risk for TLS?
Highest risk: Burkitt lymphoma (highest proliferation rate of any cancer), ALL (especially with WBC > 100K), DLBCL (with bulky disease + high LDH), AML (especially with WBC > 100K). Intermediate: most AML, CLL with high tumor burden, aggressive lymphomas. Low risk: most solid tumors (rare but described with small cell lung cancer, hepatocellular carcinoma).
Key findings: Very high TLS risk: ALL + WBC > 100K + elevated LDH + elevated uric acid + elevated PO₄ baseline. Cairo-Bishop criteria for laboratory TLS likely already met. Chemo will cause massive cell lysis.
Management:
Rasburicase 0.2 mg/kg IV × 1 dose (uricase, enzymatically degrades uric acid, onset within hours)
Aggressive IVF: D5W + NS at 200 mL/hr (target UOP > 2 mL/kg/hr, flushes uric acid and phosphate)
Do NOT give allopurinol if giving rasburicase (allopurinol prevents uric acid formation; rasburicase degrades existing uric acid, allopurinol is the backup, not add-on)
Monitor: BMP + uric acid + LDH + PO₄ q6h for first 72h after chemo starts
Dialysis standby if K⁺ > 6 refractory to medical management or Cr doubling
Teaching point: Rasburicase is contraindicated in G6PD deficiency, it generates hydrogen peroxide during uric acid degradation, causing hemolytic anemia. Always check G6PD before giving rasburicase. Also: rasburicase degrades uric acid in the blood tube ex vivo, send samples on ice for accurate levels.
📋 Case 2, Established TLS with Hyperkalemia and AKI
Patient: 55M with Burkitt lymphoma, 24h after starting R-CHOP. K⁺ 7.1, PO₄ 8.4, uric acid 14.2, Ca 6.8, Cr 4.2 (was 1.0). ECG: peaked T waves, widened QRS. Oliguric.
Key findings: Clinical TLS (laboratory TLS + organ dysfunction): hyperkalemia with ECG changes + AKI + hypocalcemia (from calcium-phosphate precipitation in renal tubules). Life-threatening emergency.
Management:
Calcium gluconate 3g IV (membrane stabilization for hyperkalemia, do NOT correct hypocalcemia aggressively as this worsens Ca×PO₄ precipitation)
Emergent hemodialysis, most effective treatment for TLS with AKI (removes K⁺, PO₄, uric acid simultaneously)
Rasburicase 0.2 mg/kg IV if not already given
IVF if any UOP remaining; sevelamer for phosphate binding
Teaching point: In TLS, do NOT aggressively correct hypocalcemia unless symptomatic (tetany, seizures, QTc prolongation), giving IV calcium in the setting of hyperphosphatemia causes calcium-phosphate precipitation in kidneys and tissues, worsening AKI. Lower the phosphate first.
📋 Case 3, Spontaneous TLS Before Chemotherapy
Patient: 42F presents with fatigue, found to have WBC 280K with 92% blasts (AML). Before any treatment: K⁺ 6.4, PO₄ 6.8, uric acid 12.4, LDH 4200, Cr 3.1. Ca 7.2.
Key findings: Spontaneous TLS, occurs before any chemotherapy due to rapid tumor cell turnover and death from massive tumor burden. Seen in highly proliferative cancers with very high WBC or bulky disease.
Management:
Rasburicase 0.2 mg/kg IV STAT (most urgent, uric acid nephropathy is the primary driver of AKI in spontaneous TLS)
Treat hyperkalemia aggressively (calcium gluconate, insulin/D50, dialysis if refractory)
Must still start chemotherapy, delaying treatment allows tumor to keep lysing spontaneously
Leukapheresis if WBC > 100K with leukostasis symptoms (addresses both leukostasis and TLS risk)
Teaching point: TLS can occur BEFORE chemotherapy in highly proliferative tumors. Any patient with WBC > 100K or LDH > 2× ULN should have TLS labs checked at presentation. Spontaneous TLS is actually a predictor of chemosensitivity, these tumors are dying fast on their own.
📣 Sample Presentation
One-Liner
"Mr. Park is a 52-year-old with newly diagnosed Burkitt lymphoma (WBC 180K) who developed K⁺ 6.8, PO₄ 8.2, uric acid 14.2, Ca²⁺ 6.8, and Cr 3.4 twelve hours after starting chemotherapy. Consistent with tumor lysis syndrome."
Key Points to Cover on Rounds
TLS -Cairo-Bishop criteria met (2+ lab abnormalities + Cr rise). Labs: K⁺ 6.8 (treated emergently -Ca gluconate, insulin/D50, albuterol), PO₄ 8.2 (sevelamer started, avoid Ca-containing binders → CaPO₄ precipitation), uric acid 14.2, Ca²⁺ 6.8 (symptomatic → Ca gluconate only if ECG changes, otherwise avoid). Treatment: rasburicase 0.2 mg/kg IV × 1 (G6PD checked and normal). Aggressive IVF at 200 mL/hr. Allopurinol stopped (rasburicase is treatment, allopurinol is prophylaxis only). Nephrology consulted -HD if refractory K⁺ or fluid overload. Labs q6h. Plan: continue aggressive hydration, rasburicase, electrolyte management.
Monitoring
K⁺, PO₄, Ca²⁺, uric acid, Cr q6-8h -for first 48-72h after chemo initiation. High-risk patients may need q4h monitoring initially.
ECG -before each lab check. Hyperkalemia (peaked T → wide QRS → sine wave) and hypocalcemia (prolonged QTc) are immediately life-threatening.
Urine output hourly -target ≥ 2 mL/kg/hr. Falling UOP = urate nephropathy or CaPO₄ precipitation → nephrology consult for possible dialysis.
Fluid balance -aggressive IVF can cause volume overload, especially in patients with impaired renal or cardiac function. Daily weights + I/Os.
Dialysis indications: refractory hyperkalemia, severe oliguria/anuria, volume overload unresponsive to diuretics, symptomatic hypocalcemia with concurrent hyperphosphatemia (can't give Ca safely)
Ca × PO₄ product -if > 60 → high risk of metastatic calcification. Prioritize phosphate lowering.
⚡ Summary
Summary
What Happens and When
Massive cell death releases potassium, phosphate and nucleic acids, which become uric acid.It occurs 12 to 72 h after starting chemotherapy, and occasionally spontaneously in very high-burden disease before any treatment. It kills through hyperkalemia, acute kidney injury and cardiac arrest.
Know the Four Lab Abnormalities and Why Calcium Falls
High potassium, high phosphate, high uric acid, low calcium.The calcium falls because the released phosphate binds it, and that calcium-phosphate product then precipitates in the renal tubules, which is one of the two mechanisms of the kidney injury. Uric acid crystals are the other.
Identify High Risk Before the First Dose
High tumor burden plus rapid proliferation: Burkitt lymphoma, ALL, high-grade lymphomas, AML with a very high white count, and bulky chemosensitive solid tumors. Add pre-existing renal impairment, volume depletion and a high baseline uric acid or LDH. Venetoclax has a particularly high risk, which is why it is ramped up rather than started at full dose.
Prevention Is Fluids Plus a Urate-Lowering Agent
Aggressive IV hydration starting 24 to 48 h before treatment, targeting a high urine output, which is the intervention that matters most. Allopurinol for standard risk, blocking xanthine oxidase so no new uric acid is made. Rasburicase for high risk or an already elevated uric acid, which enzymatically degrades existing urate and works within hours.
Rasburicase Has Two Traps
It is contraindicated in G6PD deficiency, where the hydrogen peroxide generated causes severe hemolysis and methemoglobinemia. And it continues to degrade urate in the tube after the sample is drawn, so blood for uric acid must be collected on ice and processed immediately or the level reads falsely normal.
Do Not Alkalinize the Urine
It was standard teaching and is no longer recommended. Raising the urinary pH increases uric acid solubility but promotes calcium-phosphate precipitation, trading one crystal nephropathy for another. Volume, not pH, is what protects the kidney.
Do Not Give Calcium for Asymptomatic Hypocalcemia
Giving calcium while the phosphate is high drives calcium-phosphate deposition in the kidney and worsens the acute kidney injury.Treat only symptomatic hypocalcemia, tetany, seizures or ECG change.Lower the phosphate instead, with binders and dialysis as needed.
Monitor Intensively and Know When to Dialyze
Potassium, phosphate, calcium, uric acid and creatinine every 6 to 8 h through the first 48 to 72 h, with continuous cardiac monitoring in high-risk patients. Dialyze for refractory hyperkalemia, refractory acidosis, volume overload, severe symptomatic hypocalcemia or oliguric renal failure.Involve nephrology early rather than at the point of crisis, since access and timing take planning.
RoundsRx Infographic Series · #80 · Hematology · PDF 149 KB
Text version
Oncology / Nephrology · One Pager
Tumor Lysis Syndrome
High K⁺ + high PO₄ + high uric acid + low Ca²⁺ + AKI after chemo. Prevention: hydration + allopurinol. Treatment: rasburicase + aggressive IVF + dialysis if refractory.
Rasburicase 0.2 mg/kg IV (converts existing uric acid → allantoin). Aggressive IVF 200-250 mL/hr. Treat hyperkalemia emergently. Sevelamer for hyperphosphatemia. Dialysis if refractory.
⚠️ Do NOT
Don't give calcium for hypocalcemia unless symptomatic (increases CaPO₃ precipitation). Don't give allopurinol for established TLS (only prophylaxis). Check G6PD before rasburicase (hemolysis risk).
💊 Key Drugs
Rasburicase0.2 mg/kg IV × 1 (treatment)
Allopurinol300 mg daily (prophylaxis only)
IVF200-250 mL/hr NS or D5W
Sevelamer800 mg TID (for hyperPO₄)
⚠️ Pitfalls
Allopurinol for established TLS (doesn't break down existing uric acid)
IV calcium for hypocalcemia (CaPO₃ precipitation → renal damage)
Not monitoring labs q6-8h after chemo in high-risk tumors
Functional asplenia makes these patients vulnerable to encapsulated organisms -fever is a medical emergency. VOC is the most common reason for hospitalization. ACS is the #1 cause of death. Hydroxyurea saves lives.
🔍 Overview
Acute Complications
Complication
Features
Management
Vaso-occlusive crisis (VOC)
Severe pain (bones, chest, abdomen) triggered by dehydration, cold, infection, stress
Aggressive pain control (IV opioids -PCA preferred), IVF (NS or D5 1/2 NS at 1.5× maintenance), incentive spirometry q2h (prevents ACS)
Acute chest syndrome (ACS)
New infiltrate on CXR + one of: fever, chest pain, cough, hypoxia, tachypnea. #1 cause of death in SCD.
IVF, analgesia, aspiration/irrigation by urology. Exchange transfusion if refractory. > 4h → ischemic → impotence risk.
Infections & Sepsis in Sickle Cell
Fever ≥ 38.3°C (101°F) in SCD = medical emergency. Functional asplenia → cannot clear encapsulated organisms. Start empiric ceftriaxone within 1 hour of presentation. Do NOT wait for cultures. Mortality from overwhelming post-splenectomy sepsis can be > 50% if delayed.
Why Are SCD Patients at Risk?
By age 5, most HbSS patients have functional asplenia from repeated splenic infarction (autosplenectomy). The spleen is the primary filter for encapsulated bacteria -without it, these organisms can cause fulminant sepsis within hours. This is the same risk as surgically asplenic patients.
Key Organisms
Organism
Clinical Scenario
Key Points
Streptococcus pneumoniae #1 KILLER
Bacteremia, pneumonia, meningitis
Most common cause of fatal sepsis in SCD. Can progress from well → dead in < 12 hours. Penicillin prophylaxis (age < 5) + pneumococcal vaccines (PCV13 → PPSV23) are essential.
Haemophilus influenzae type b
Bacteremia, pneumonia, meningitis
Second most common encapsulated pathogen. Hib vaccine has dramatically reduced incidence.
In the general population, S. aureus is #1 for osteomyelitis. In SCD, Salmonella is #1 (infarcted bone is a perfect growth medium). Also causes bacteremia and GI infections.
Capnocytophaga canimorsus DOG/CAT BITE
Dog or cat bite, scratch, or saliva exposure
Gram-negative rod found in dog/cat saliva. In asplenic/functionally asplenic patients → fulminant sepsis, DIC, purpura fulminans, gangrene. Mortality 25–30% in asplenic patients. Treat with amoxicillin-clavulanate (bite prophylaxis) or piperacillin-tazobactam (if septic). Any SCD patient with a dog or cat bite needs immediate antibiotics and close monitoring.
Parvovirus B19
Aplastic crisis (NOT sepsis)
Infects erythroid precursors → transient red cell aplasia. Retic count drops to near zero. Self-limited but may need transfusion.
Fever Workup in SCD
Blood cultures × 2 (before antibiotics -but do NOT delay antibiotics if cultures take time)
CBC with differential -WBC, Hgb vs baseline, reticulocyte count
CXR -rule out ACS and pneumonia
Urinalysis + urine culture -UTI common
CMP -check for end-organ damage
Empiric ceftriaxone 2g IV -covers encapsulated organisms. Add vancomycin if toxic-appearing, meningitis suspected, or local DRSP rates are high
Required Vaccinations
Vaccine
Schedule
PCV13 → PPSV23
PCV13 series in childhood. PPSV23 at age 2, booster at age 5, then q5 years. Both types needed.
MenACWY
Primary series + booster every 5 years (lifelong in asplenic patients)
MenB
2-dose or 3-dose series (depending on product)
Hib
Standard childhood series. If unvaccinated adult, give 1 dose.
Influenza
Annual -respiratory infections trigger ACS
Penicillin prophylaxis: Penicillin VK 125 mg PO BID (age < 3) → 250 mg PO BID (age 3–5). Recommended for all HbSS children through age 5. PROPS, 1986: reduced pneumococcal sepsis by 84%. Discontinuation after age 5 is debated -many hematologists continue longer in high-risk patients.
🚨 Management
VOC Pain Management
Pain is real and severe. Treat aggressively. These patients are NOT drug-seeking. Chronic opioid tolerance means they need higher doses than you'd typically give. Use a PCA.
IV opioids: PCA (patient-controlled analgesia) is preferred. Hydromorphone or morphine. Titrate to pain relief.
Multimodal: ketorolac 15–30 mg IV q6h (if no AKI), acetaminophen 1g IV q6h, lidocaine patch
IVF: NS or D5 1/2 NS at 1.5× maintenance. Avoid over-hydration (risk of ACS).
Incentive spirometry q2h while awake -prevents atelectasis → ACS. Most important preventive measure during VOC admission.
Transfusion: simple transfusion if Hgb < 7 or > 2 below baseline. Target Hgb ≤ 10 (higher viscosity worsens sickling).
Disease-Modifying Therapy
Drug
Mechanism
Key Notes
Hydroxyurea 1ST LINE
↑ HbF production → ↓ sickling. Also ↓ WBC (anti-inflammatory), ↑ NO, ↑ MCV.
Most important disease-modifying drug. Reduces crises by 50%, reduces ACS, reduces mortality. MSH, 1995. Offer to ALL patients with ≥ 3 crises/year (or any ACS/stroke). Teratogenic -contraception required.
Voxelotor (Oxbryta)
HbS polymerization inhibitor -stabilizes oxy-Hb state
↑ Hgb by ~1 g/dL. FDA-approved. Long-term outcomes still being studied.
Crizanlizumab (Adakveo)
Anti-P-selectin monoclonal antibody -blocks sickle cell adhesion to endothelium
SUSTAIN, 2017: reduced median annual crises from 2.98 to 1.63. IV infusion monthly.
L-glutamine (Endari)
Reduces oxidative stress in RBCs
PO BID. Reduced crises by ~25%. Second-line add-on.
💊 Medications
Key Medications -Sickle Cell
Drug
Dose
Indication
Key Notes
Hydromorphone (Dilaudid)
0.5–1 mg IV q2–3h PRN or PCA
VOC pain
PCA preferred. Titrate to pain control. These patients have opioid tolerance -use adequate doses.
Ketorolac (Toradol)
15–30 mg IV q6h (max 5 days)
VOC adjunct
Avoid if AKI. Reduces opioid requirements. Hold if Cr rising.
Ceftriaxone (Rocephin)
2g IV q24h
Febrile SCD / ACS
Empiric coverage for encapsulated organisms. Combine with azithromycin for ACS.
Why do you target Hgb ≤ 10 when transfusing SCD patients?
Sickle cell patients have adapted to chronic anemia -their blood viscosity is calibrated to a lower Hgb. Transfusing to a "normal" Hgb (> 10) increases whole blood viscosity → paradoxically worsens vaso-occlusion and can trigger more crises. The optimal target is Hgb ≤ 10 g/dL. In exchange transfusions, the goal is to dilute HbS to < 30% while keeping total Hgb ≤ 10.
Why is incentive spirometry so important during VOC admission?
Chest wall pain during VOC → splinting → atelectasis → local hypoxia → triggers sickling in pulmonary vasculature → acute chest syndrome. ACS is the #1 cause of death in SCD and often develops during VOC admissions. Incentive spirometry q2h while awake prevents atelectasis and is the single most effective ACS prevention strategy during hospitalization -more important than any medication.
A sickle cell patient presents with fever, DIC, and purpura after a dog bite 2 days ago. What organism?
Capnocytophaga canimorsus -a gram-negative rod found in dog and cat saliva. In functionally asplenic patients (like SCD), it causes fulminant sepsis with DIC, purpura fulminans, and gangrene. Mortality is 25–30% in asplenic patients. This is why any dog or cat bite in a sickle cell patient needs immediate prophylactic antibiotics (amoxicillin-clavulanate). If already septic → piperacillin-tazobactam or meropenem.
What is the most common cause of osteomyelitis in sickle cell disease?
Salmonella -NOT Staph aureus. In the general population, S. aureus is #1 for osteomyelitis. In SCD, repeated bone infarctions create an ideal environment for Salmonella seeding. This is a classic boards distinction. However, S. aureus is still the #1 cause of septic arthritis in SCD. Mnemonic: Sickle cell + bone = Salmonella.
When do you do an exchange transfusion instead of a simple transfusion in sickle cell?
Why is incentive spirometry so important in sickle cell crisis?
Acute chest syndrome (ACS) is the #1 cause of death in SCD during hospitalization. It develops when VOC-related pain → splinting (shallow breathing to avoid pain) → atelectasis → ventilation-perfusion mismatch → local hypoxia → more sickling in pulmonary vasculature → infarction → ACS. Incentive spirometry (IS) breaks this cycle -deep breaths recruit collapsed alveoli, prevent atelectasis, and maintain oxygenation.
Clinical Examples
📋 Case 1, Vaso-Occlusive Crisis (VOC)
Patient: 22F with HbSS, presents with severe bilateral leg and back pain 10/10, not relieved by home oxycodone. Temp 37.8°C, HR 108. WBC 15K, Hgb 7.0 (baseline 7.5), retic 12%. No new infiltrate on CXR.
Key findings: Typical VOC: severe pain in bones/joints, mild fever (from inflammation, not necessarily infection), slight Hgb drop. No ACS (no infiltrate, no hypoxia). Pain management is the primary intervention.
Management:
IV opioids within 30 min of arrival: hydromorphone 0.5-1 mg IV q15-20min until pain controlled (PCA if repeated doses needed)
IV ketorolac 15-30 mg q6h (NSAID, reduces opioid requirement by 30-40%)
IVF: NS or D5-½NS at 1-1.5× maintenance (avoid overhydration → ACS risk)
Incentive spirometry q2h while awake (prevents ACS, the #1 killer during VOC hospitalization)
Avoid: under-treating pain (causes splinting → atelectasis → ACS), over-hydration, excessive supplemental O₂ (suppress erythropoiesis if not hypoxic)
Teaching point: Incentive spirometry is the most important nursing order in SCD, it prevents ACS. Pain management is not optional, undertreated pain → splinting → ACS → death. Treat pain aggressively and reassess frequently.
📋 Case 2, Acute Chest Syndrome
Patient: 28M with HbSS, admitted 2 days ago for VOC. Now develops fever 39.2°C, cough, pleuritic chest pain, SpO₂ 88% on RA. CXR: new RLL infiltrate. Hgb dropped 7.5 → 6.2.
Key findings: ACS = new pulmonary infiltrate + one of: chest pain, fever, hypoxia, cough. Developed during VOC hospitalization (classic, splinting → atelectasis → sickling → ACS). #1 cause of death in SCD during hospitalization.
Management:
Simple transfusion to Hgb 10 (if Hgb < 9 or dropping; avoid Hgb > 10 in SCD → hyperviscosity)
Exchange transfusion if severe (SpO₂ < 90% despite O₂, multilobar infiltrates, rapid deterioration), target HbS < 30%
Ceftriaxone 2g IV + azithromycin 500 mg IV (cover typical + atypical pathogens, infection triggers ~50% of ACS)
Supplemental O₂ to SpO₂ ≥ 95%, incentive spirometry, bronchodilators if wheezing
Continue pain management, do NOT reduce opioids just because ACS developed (pain → splinting → worsens ACS)
Teaching point: ACS and pneumonia are indistinguishable on imaging, treat for both. Exchange transfusion is the definitive treatment for severe ACS. Simple transfusion is sufficient for mild-moderate cases. Never let Hgb exceed 10 g/dL in SCD.
📋 Case 3, Stroke in Sickle Cell Disease
Patient: 8-year-old girl with HbSS presents with sudden right hemiplegia and aphasia. CT head: no hemorrhage. CT angiography: left MCA stenosis. Hgb 6.8, HbS 78%.
Key findings: Ischemic stroke from large-vessel vasculopathy, affects 11% of SCD children by age 20. Sickled RBCs damage endothelium → intimal hyperplasia → stenosis of large cerebral vessels (especially ICA and MCA).
Management:
Emergent exchange transfusion, target HbS < 30%, Hgb ~10 (do NOT wait, this is the #1 treatment)
IV tPA is NOT standard in SCD stroke (exchange transfusion is preferred and more effective for the underlying pathology)
Chronic transfusion program: monthly simple transfusions to maintain HbS < 30% indefinitely (reduces stroke recurrence from 67% to 10%)
Consider transition to hydroxyurea after 1+ year of transfusions (SWiTCH trial) if iron overload problematic
Transcranial Doppler (TCD) screening annually for all SCD children ages 2-16, abnormal velocity (> 200 cm/s) predicts stroke risk
Teaching point: TCD screening is one of the most impactful preventive measures in SCD, identifying high-risk children and starting chronic transfusions reduces primary stroke risk by 92% (STOP trial). Every SCD child needs annual TCD.
📣 Sample Presentation
One-Liner
"Ms. Brown is a 24-year-old with SCD (HbSS) presenting with severe bilateral leg and back pain rated 10/10, not relieved by home oxycodone. WBC 14K, Hgb 7.2 (baseline 8.0). No fever. Consistent with vaso-occlusive crisis."
Key Points to Cover on Rounds
VOC -pain crisis. Pain management: IV hydromorphone 0.5 mg q2h PRN started within 30 min of arrival (multimodal: + ketorolac 15 mg IV + acetaminophen 1g). Incentive spirometry q2h while awake (prevents ACS). Hydration: D5 1/2NS at 125 mL/hr. Hgb 7.2 (baseline 8.0) → no transfusion yet (threshold 7, or if significant drop). No transfuse above 10 (hyperviscosity). CXR baseline -no ACS. Reticulocyte count 8% (appropriate). On hydroxyurea at home -continued. Plan: aggressive pain control, IS compliance, monitor for ACS (fever + new infiltrate + respiratory symptoms).
⚡ Summary
Summary
Fever Is a Medical Emergency
Functional asplenia leaves these patients vulnerable to encapsulated organisms, so a temperature of 38.5°C or above means immediate blood cultures and empiric ceftriaxone.Do not wait for a source, and do not treat it as a viral illness: overwhelming pneumococcal sepsis can kill within hours.
Acute Chest Syndrome Is the Leading Cause of Death
A new pulmonary infiltrate with fever, chest pain, hypoxia or respiratory symptoms.Treat with antibiotics covering atypicals, oxygen, incentive spirometry, adequate analgesia and early transfusion, with exchange transfusion for severe or progressive disease. It frequently develops 24 to 72 h into an admission for pain, often precipitated by hypoventilation from opioids and splinting, which is why incentive spirometry is prescribed to every admitted patient.
Treat Vaso-Occlusive Pain Fast and Without Suspicion
Give the first parenteral opioid within 30 to 60 minutes of arrival, using the patient's own individualized plan where one exists.These patients are systematically under-treated and mislabeled as drug-seeking, and delay is both a quality failure and a driver of acute chest syndrome. Add scheduled NSAIDs, hydration to euvolemia and warmth.
Do Not Over-Hydrate or Over-Oxygenate
Give maintenance fluids, not aggressive boluses: volume overload precipitates acute chest syndrome. Oxygen only for hypoxemia, since it does not relieve pain in a normoxic patient and can suppress erythropoiesis with prolonged use.
Hydroxyurea Saves Lives
It raises fetal hemoglobin, reducing crises, acute chest syndrome, transfusion need and mortality.Indicated for recurrent pain crises, prior acute chest syndrome, severe anemia, and increasingly for all patients with HbSS. Monitor the blood count for myelosuppression, and counsel on contraception given teratogenicity. Newer agents (voxelotor, crizanlizumab, L-glutamine) and curative gene therapy and transplant now supplement it.
Know Which Crisis You Are Looking At
Aplastic crisis: a sudden fall in hemoglobin with a low reticulocyte count, classically parvovirus B19.Splenic sequestration: a falling hemoglobin with a rapidly enlarging spleen, mostly in children, and it can exsanguinate into the spleen.Hyperhemolytic crisis.The reticulocyte count separates them and directs the treatment.
Transfuse With a Purpose
Simple transfusion for symptomatic anemia; exchange transfusion for stroke, severe acute chest syndrome, multi-organ failure and preoperatively in some cases.Target a hemoglobin around 10 and do not exceed it, because raising it further increases viscosity and worsens vaso-occlusion. Use phenotypically matched blood, since alloimmunization is common and makes future crossmatching progressively harder. Delayed hemolytic transfusion reaction can mimic a pain crisis.
Prevent the Chronic Complications
Penicillin prophylaxis in children, and full vaccination against encapsulated organisms.Transcranial Doppler screening in children to identify stroke risk, which chronic transfusion then prevents. Annual retinal screening, renal function and urine protein, pulmonary hypertension assessment, and monitoring for avascular necrosis of the hip.Priapism lasting over 4 hours is a urologic emergency.
When to transfuse, what products to use, and how to manage reactions. Restrictive is better for most patients. Know the thresholds and the reactions -you'll order blood products daily.
🩸 Transfusion Thresholds
Product
Threshold
Evidence
pRBCs -general RESTRICTIVE
Hgb < 7 g/dL
TRICC, 1999: restrictive (7) non-inferior to liberal (10) in ICU. TRICS-III, 2017: confirmed in cardiac surgery.
pRBCs -ACS
Hgb < 8 g/dL (or symptomatic anemia)
REALITY, 2021: restrictive (8) vs liberal (10) -non-inferior for 30-day MACE in MI.
pRBCs -active bleeding
Hgb < 7–8, but transfuse to symptoms/hemodynamics
MTP: 1:1:1 ratio PROPPR, 2015 (pRBC:FFP:platelets). Don't wait for lab values in massive hemorrhage.
Platelets -general
< 10,000 (prophylactic)
Higher thresholds for active bleeding (< 50K), neurosurgery (< 100K), or procedures.
FFP
Active bleeding + INR > 1.5
15 mL/kg. Or 4F-PCC for warfarin reversal (faster, less volume).
Cryoprecipitate
Fibrinogen < 100–150 (DIC, massive transfusion)
10 units raises fibrinogen ~50–70 mg/dL. Key product in DIC.
🔄 Updated Practice: Old teaching: transfuse when Hgb <10 ("10/30 rule"). Current evidence: restrictive strategy (Hgb <7) is as safe or safer than liberal (Hgb <10) in most ICU patients (TRICC, 1999; TRISS, 2014). Exceptions: active ACS (transfuse <8), symptomatic anemia, active hemorrhage. For upper GI bleed, restrictive transfusion (Hgb <7) actually IMPROVED survival (Villanueva, 2013).
💉 Blood Products
Product
Contains
Expected Effect
Special Considerations
pRBCs
Red blood cells in additive solution
↑ Hgb ~1 g/dL per unit
Type & screen required. Irradiate if immunocompromised (prevent TA-GVHD). CMV-negative or leukoreduced for transplant candidates.
Platelets
Platelets (apheresis or pooled)
↑ 30,000–50,000 per unit
ABO-compatible preferred. Room temperature storage (not refrigerated). 5-day shelf life. Highest bacterial contamination risk of all blood products.
FFP
All clotting factors
↑ factor levels ~20–30%
ABO-compatible required. Thaw time ~30 min. Volume ~250 mL/unit (risk of TACO).
Cryoprecipitate
Fibrinogen, Factor VIII, vWF, Factor XIII
↑ fibrinogen ~50–70 mg/dL per 10 units
Key for DIC, massive transfusion, factor XIII deficiency. Pooled (10 units = 1 dose).
⚠️ Transfusion Reactions
First step in ANY suspected reaction: STOP the transfusion. Maintain IV access. Check vitals. Send a clerical check + blood sample to the blood bank.
Reaction
Timing
Features
Management
Acute hemolytic (ABO mismatch)
Minutes
Fever, flank pain, dark urine, hypotension, DIC. Most dangerous. Usually clerical error.
STOP immediately. IVF (prevent renal failure), send direct Coombs + repeat type & screen. Supportive ICU care.
Febrile non-hemolytic (FNHTR)
1–6 hours
Fever, rigors. Most common reaction. Cytokines from donor WBCs.
Stop, rule out hemolytic. Acetaminophen. Leukoreduced products prevent recurrence.
Allergic (mild)
During
Urticaria, pruritus. No fever or hemodynamic changes.
Stop temporarily. Diphenhydramine 25–50 mg IV. Can resume slowly if mild.
Anaphylactic
Minutes
Hypotension, bronchospasm, angioedema. Often in IgA-deficient patients (anti-IgA antibodies).
Epinephrine 0.3–0.5 mg IM. IVF, steroids, bronchodilators. Future: washed or IgA-deficient products.
TRALI
≤ 6 hours
Acute respiratory distress + bilateral infiltrates + hypoxia within 6h. No volume overload. Caused by donor antibodies activating recipient neutrophils in lungs.
Supportive (O₂, ventilation). Diuretics do NOT help (not a volume issue). Usually resolves 48–96h. Report to blood bank.
TACO
≤ 6 hours
Volume overload → pulmonary edema, HTN, JVD. Distinguished from TRALI by: elevated BNP, response to diuretics, hypertension.
Diuretics. Slow transfusion rate for future products
🔍 Overview
Overview
Blood product transfusion is one of the most common inpatient procedures. Restrictive thresholds (Hgb < 7) are standard for most patients [TRICC, 1999; TRISS, 2014] -liberal transfusion does not improve outcomes and may worsen them. In acute coronary syndrome, threshold is Hgb < 8. Always transfuse 1 unit at a time and recheck before ordering more. Massive transfusion protocol (MTP): 1:1:1 ratio of pRBC:FFP:platelets + TXA 1g IV [CRASH-2, 2010; PROPPR, 2015]. Key reactions to recognize: TRALI (non-cardiogenic pulmonary edema, normal BNP, within 6h) vs TACO (volume overload, elevated BNP, responds to diuretics). Stop transfusion immediately for any suspected reaction.
🧪 Workup
Workup
Type & screen -ABO + Rh typing + antibody screen. Required before all transfusions. Valid for 72h in recently transfused/pregnant patients.
Crossmatch -for elective/non-emergent transfusion. Takes 30-60 min. In emergency: use O-negative (universal donor) while crossmatch pending.
CBC -Hgb (transfusion threshold), platelet count (threshold 10K for prophylactic, 50K for invasive procedure, 100K for neurosurgery)
Coagulation studies -PT/INR (FFP threshold: INR > 1.5 with active bleeding), fibrinogen (cryoprecipitate threshold: < 100-150 mg/dL)
Direct Coombs (DAT) -if suspected transfusion reaction or hemolytic anemia. Positive = antibodies coating RBCs.
Indirect Coombs (IAT) -detects circulating antibodies. Part of antibody screen. Positive → need antigen-negative units.
Post-transfusion Hgb -check 1-2h after transfusion. Expected rise: ~1 g/dL per unit pRBC. If less → consider ongoing bleeding, hemolysis, or hypersplenism.
For suspected reaction: stop transfusion → send bag + tubing to blood bank → direct Coombs → free hemoglobin (plasma/urine) → haptoglobin → repeat type & screen → UA for hemoglobinuria → chest imaging if respiratory symptoms
Hgb < 8 -acute coronary syndrome, symptomatic anemia, acute GI bleed with hemodynamic instability
Hgb < 10 -rarely indicated (active MI with ongoing ischemia, severe symptomatic anemia)
Platelets < 10K -prophylactic (no bleeding)
Platelets < 50K -active bleeding or invasive procedure
Platelets < 100K -neurosurgery, ocular surgery
FFP -INR > 1.5 with active bleeding. NOT for "correcting" INR without bleeding.
Cryoprecipitate -fibrinogen < 100-150 mg/dL
Massive transfusion protocol (MTP): pRBC:FFP:platelets = 1:1:1 PROPPR, 2015. Activate early in hemorrhagic shock. TXA 1g IV within 3h of injury CRASH-2, 2010. Calcium gluconate 1g after every 4 units (citrate chelates calcium).
Transfusion reactions:
Febrile non-hemolytic (most common): fever + rigors within 1-6h. Stop, rule out hemolytic. Acetaminophen. Resume with leukoreduced products.
Special products: irradiated (prevent TA-GVHD in immunocompromised), CMV-negative (transplant recipients), leukoreduced (prevent febrile reactions + CMV), washed (IgA deficiency, severe allergic reactions)
📋 On Rounds
How do you distinguish TRALI from TACO?
Both present with respiratory distress + bilateral infiltrates within 6h of transfusion. TRALI: non-cardiogenic pulmonary edema (BNP normal or low, hypotension, no JVD, does NOT respond to diuretics). Caused by donor antibodies. TACO: cardiogenic volume overload (BNP elevated, hypertension, JVD, responds to diuretics). Risk factors: CHF, CKD, rapid infusion rate, multiple units. Key distinguisher: give furosemide. If they improve → TACO.
Why Hgb 7, not 10?
TRICC, 1999 randomized ICU patients to restrictive (Hgb 7) vs liberal (Hgb 10) transfusion. Restrictive was non-inferior for 30-day mortality and had fewer cardiac events. Multiple subsequent trials confirmed this across cardiac surgery TRICS-III, 2017, GI bleed Villanueva, 2013, and hip surgery FOCUS, 2011.
What is TRALI and how do you differentiate it from TACO?
Both present with respiratory distress during/after transfusion, but treatment is opposite. TRALI (Transfusion-Related Acute Lung Injury): non-cardiogenic pulmonary edema. Onset within 6h. Bilateral infiltrates on CXR. NO signs of volume overload (BNP normal/low, no JVD, no S3). Due to donor antibodies activating recipient neutrophils → capillary leak. Treatment: supportive (O₂, intubation if needed, NO diuretics).
What is the transfusion threshold for most hospitalized patients?
Restrictive threshold: Hgb < 7 g/dL for most hospitalized patients.TRICC, 1999 and TRISS, 2014: restrictive (Hgb < 7) was non-inferior to liberal (Hgb < 10) for mortality. Liberal transfusion did NOT improve outcomes and increased complications. Exception: Hgb < 8 for ACS/active cardiac ischemia (the MINT trial MINT, 2023 suggested possible benefit, though not definitive).
❓ How do you differentiate TRALI from TACO?
TRALI = non-cardiogenic pulmonary edema. Normal BNP, bilateral infiltrates within 6h, no fluid overload signs, does NOT respond to diuretics. Supportive care only -resolves 48-72h. TACO = volume overload. Elevated BNP, responds to furosemide, often hypertensive. Prevention: slow transfusion rate, furosemide between units in HF/CKD patients.
❓ What is the expected hemoglobin rise per unit of pRBC transfused?
~1 g/dL per unit in a 70 kg adult. If the post-transfusion Hgb rise is less than expected, consider: (1) ongoing hemorrhage, (2) hemolysis (check Coombs, LDH, haptoglobin), (3) hypersplenism, (4) volume overload diluting the measurement, (5) lab draw from a diluted line.
❓ When do you give cryoprecipitate and what does it contain?
Cryoprecipitate contains: fibrinogen (most important), Factor VIII, Factor XIII, vWF, and fibronectin. Give when fibrinogen < 100-150 mg/dL (DIC, massive transfusion, post-thrombolytics). Dose: 10 units (1 pool) raises fibrinogen ~70 mg/dL. In massive hemorrhage, check fibrinogen early and replace aggressively -it is the first factor to become critically depleted.
❓ What is a delayed hemolytic transfusion reaction (DHTR)?
DHTR occurs 3-14 days after transfusion due to anamnestic antibody response (patient was previously sensitized but antibody titer dropped below detection). Presents with: unexplained Hgb drop, new jaundice, dark urine, positive DAT. Especially dangerous in SCD patients -can cause hyperhemolysis (destruction of both transfused AND native RBCs). Prevention: extended phenotype matching.
❓ What does TXA do and when is it indicated in massive hemorrhage?
Tranexamic acid (TXA) inhibits fibrinolysis by blocking plasmin. Give 1g IV within 3 hours of hemorrhage onset -later administration may be harmful. Evidence: CRASH-2, 2010 -reduced mortality in trauma. WOMAN, 2017 -reduced death from postpartum hemorrhage. No benefit shown in GI bleeding HALT-IT, 2020. Include in all massive transfusion protocols.
Clinical Examples
📋 Case 1, Acute Hemolytic Transfusion Reaction
Patient: 62M receiving unit of pRBCs for Hgb 6.2. Within 15 min: rigors, fever 39.8°C, severe flank pain, dark urine. BP 82/48. Nursing notes: unit labeled "type A" but patient is "type O."
Key findings: ABO-incompatible transfusion, the most dangerous transfusion reaction. Patient (type O) has preformed anti-A antibodies → immediate intravascular hemolysis → DIC, shock, renal failure. Almost always a clerical/labeling error.
Management:
STOP transfusion immediately, do NOT continue even a drop
Maintain IV access with NS. Aggressive IVF to maintain UOP > 1 mL/kg/hr (prevent hemoglobin-induced AKI)
Send: DAT, repeat type and crossmatch, free hemoglobin, LDH, haptoglobin, fibrinogen, DIC panel
Return blood bag + tubing to blood bank for investigation
Monitor for DIC (fibrinogen, PT/PTT, D-dimer), replace products as needed
Teaching point: Acute hemolytic reactions are almost always human error, wrong blood to wrong patient. The bedside nurse check (patient ID + unit label + blood bank tag) is the last line of defense. Two-person verification at bedside prevents this lethal error.
📋 Case 2, TRALI vs TACO
Patient: 75F with HFrEF (EF 30%), received 2 units pRBCs for Hgb 6.8 (GI bleed). 4 hours after second unit: acute dyspnea, SpO₂ 84%, bilateral crackles, HTN (180/95). CXR: bilateral pulmonary infiltrates. BNP 2400.
Key findings: Elevated BNP + hypertension + responds to diuresis = TACO (transfusion-associated circulatory overload), NOT TRALI. TRALI would have normal BNP, hypotension, and would NOT respond to furosemide. This patient's underlying HF + rapid transfusion → volume overload.
Management:
Furosemide 40 mg IV (diagnostic AND therapeutic, TACO responds, TRALI does not)
Upright positioning, supplemental O₂, BiPAP if needed
If this were TRALI: supportive O₂ only, NO diuretics, may need intubation, resolves 48-72h
Prevention for future transfusions: slow rate (1 unit over 3-4h), furosemide 20 mg IV between units, limit to 1 unit at a time
Report to blood bank (both TACO and TRALI are reportable)
Teaching point: The BNP is the best discriminator: TACO = elevated BNP (volume overload). TRALI = normal BNP (capillary leak). When in doubt, give furosemide, if the patient improves, it's TACO. TACO is now more common than TRALI since leukoreduction reduced TRALI incidence.
📋 Case 3, Massive Transfusion Protocol
Patient: 32F with ruptured ectopic pregnancy, HR 140, BP 68/30, Hgb 4.2. Actively hemorrhaging. MTP activated.
Key findings: Class IV hemorrhagic shock (> 40% blood volume loss). Massive transfusion protocol (MTP) = ≥ 10 units pRBCs in 24h or ≥ 4 units in 1h. Goal: 1:1:1 ratio (pRBC:FFP:platelets) per PROPPR trial.
Management:
MTP packs: 6 pRBC + 6 FFP + 1 apheresis platelet (delivered as a cooler from blood bank)
1:1:1 ratio of pRBC:FFP:platelets PROPPR, 2015
TXA 1g IV within 3h of hemorrhage onset → 1g over 8h CRASH-2, 2010
Replace calcium: 1g calcium gluconate per 4 units pRBCs (citrate in blood products chelates calcium → hypocalcemia → cardiac dysfunction)
Check fibrinogen early, give cryo if < 150 (fibrinogen is the first factor to become critically depleted)
Teaching point: The biggest mistakes in massive transfusion: (1) giving crystalloid instead of blood (dilutes coagulation factors), (2) forgetting calcium replacement (citrate toxicity → cardiac arrest), (3) not checking fibrinogen early (depletes before other factors). Resuscitate with blood, not saline.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 68-year-old who developed rigors, fever 39.2°C, and back pain 20 minutes into a pRBC transfusion. BP dropped from 130/80 to 88/52. Transfusion stopped immediately."
Key Points to Cover on Rounds
Suspected acute hemolytic transfusion reaction (fever + hypotension + back pain during transfusion). Immediate actions: (1) transfusion STOPPED, (2) IV access maintained with NS, (3) patient ID rechecked against blood product -mismatch identified (wrong unit hung). Reaction workup sent: repeat type & screen, direct Coombs (DAT), free hemoglobin, LDH, haptoglobin, UA (hemoglobinuria). Blood bank notified immediately. IVF resuscitation for hypotension. Monitoring for DIC (PT/INR, fibrinogen, D-dimer q4h). Plan: supportive care, if Hgb still needed → crossmatch new unit with correct sample.
10 units (1 pool). Raises fibrinogen ~50–70 mg/dL. Contains fibrinogen, Factor VIII, vWF, Factor XIII.
Tranexamic acid (TXA)
Massive hemorrhage -within 3 hours of onset
1g IV over 10 min, then 1g over 8h. CRASH-2, 2010. Inhibits fibrinolysis. Include in all MTP activations.
Premedication
Premedication (acetaminophen 650 mg PO + diphenhydramine 25–50 mg IV/PO) is only indicated if the patient has had a prior febrile or allergic transfusion reaction. Routine premedication for all transfusions is NOT recommended -it delays the transfusion, adds cost, and does not prevent serious reactions (TRALI, hemolytic). Leukoreduction is more effective than premedication for preventing FNHTR.
⚡ Summary
Summary
Restrictive Is the Default
Transfuse red cells below 7 g/dL in most hospitalized patients.The old 10/30 rule is obsolete: TRICC and TRISS showed a restrictive strategy is as safe or safer. Exceptions where 8 is used: active coronary syndrome, and some post-operative orthopedic and cardiac surgery patients.
One Unit at a Time, Then Reassess
A single unit raises hemoglobin by about 1 g/dL in an average adult.Order one unit, then recheck and reassess rather than reflexively ordering two. Transfusion is a decision about the patient, not about a number: symptoms, ongoing bleeding and hemodynamics matter more than the value.
Know the Other Product Thresholds
Platelets: below 10,000 prophylactically, below 20,000 with fever or sepsis, below 50,000 for most procedures or active bleeding, below 100,000 for neurosurgery or ocular surgery.Plasma: for active bleeding or an urgent procedure with a significantly prolonged PT or aPTT, not to correct a number. Cryoprecipitate: for fibrinogen below 100 to 150.
Do Not Transfuse to Normalize Labs
Plasma given for a mildly abnormal INR in a non-bleeding patient does not reduce bleeding and does expose them to TRALI, TACO and allergic reactions.This is especially true in cirrhosis, where hemostasis is rebalanced and the INR overstates the bleeding risk. The number is not the patient.
Stop the Transfusion for Any Suspected Reaction
Stop, keep the line open with saline, check vital signs, and send the bag plus a fresh sample to the blood bank with a clerical recheck.Wrong blood to the wrong patient is the leading cause of fatal acute hemolytic reactions, so the identity check at the bedside is the highest-yield safety step in the whole process.
Sort Reactions by Timing and Vitals
Minutes with fever, flank pain and dark urine: acute hemolytic.Minutes with hypotension, bronchospasm and angioedema: anaphylaxis, think IgA deficiency.1 to 6 h with fever and no hemolysis: febrile non-hemolytic, the commonest.Hypoxia with bilateral infiltrates: TRALI if hypotensive with a normal JVP, TACO if hypertensive with a raised JVP and BNP.
Match the Product Modification to the Risk
Irradiated to prevent transfusion-associated GVHD in the immunocompromised and in directed donations from relatives.Leukoreduced to reduce febrile reactions, alloimmunization and CMV transmission.Washed for IgA deficiency and recurrent severe allergic reactions.Ordering the wrong modifier in an at-risk patient is what causes transfusion-associated GVHD, which is over 90% fatal.
Do Not Premedicate Routinely
Acetaminophen and diphenhydramine before every unit does not prevent serious reactions and simply masks the early fever that would have prompted you to stop. Reserve premedication for patients with a documented prior febrile or allergic reaction.Consent, verify the type and screen, and use a filtered set with normal saline only, since dextrose hemolyzes and calcium-containing fluids clot in the line.
RoundsRx Infographic Series · #138 · Hematology · PDF 145 KB
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Hematology · One Pager
Transfusion Medicine
Threshold Hgb < 7 for most. 1:1:1 for MTP. TRALI vs TACO: BNP differentiates. Stop + workup any suspected reaction. Type & screen before all transfusions.
🧪 Thresholds
Hgb < 7 for most patients [TRICC, TRISS]. Hgb < 8 for active cardiac ischemia. Massive hemorrhage: 1:1:1 ratio (pRBC:FFP:plt) + TXA [CRASH-2].
Immune-mediated platelet activation by anti-PF4/heparin antibodies. Paradoxically a PRO-thrombotic state despite low platelets. The platelets drop, but the patient clots. Stop ALL heparin immediately and switch to a non-heparin anticoagulant.
🔍 Overview
4T Score (Pretest Probability) -likelihood of heparin-induced thrombocytopenia (HIT); guides whether to send anti-PF4 and stop heparin
Criterion
2 Points
1 Point
0 Points
Thrombocytopenia
Drop > 50% AND nadir ≥ 20K
Drop 30–50% OR nadir 10–19K
Drop < 30% OR nadir < 10K
Timing
Days 5–10 OR ≤ 1 day if prior heparin within 30 days
Days 5–10 (unclear) OR > day 10
< day 4 (no prior exposure)
Thrombosis
New thrombosis, skin necrosis, or anaphylaxis post-heparin bolus
Progressive or recurrent thrombosis
None
Other causes
No other cause for thrombocytopenia
Possible other cause
Definite other cause
0–3: low probability (< 5%) → HIT unlikely, no further testing. 4–5: intermediate → send PF4 antibody, start non-heparin anticoagulant. 6–8: high probability → treat as HIT while awaiting confirmatory tests.
Key Features
Timing: platelet drop typically 5–10 days after heparin initiation (or within 24h if prior heparin exposure within 30 days -rapid onset HIT)
Platelet drop: usually > 50% from baseline (not absolute count -a drop from 300K to 130K is HIT)
Thrombosis in 50%: DVT/PE (most common), arterial (stroke, MI, limb ischemia), skin necrosis at heparin injection sites
UFH >> LMWH for HIT risk (but LMWH can also cause it -cross-reactivity ~90%)
🚨 Management
Immediate Actions
Stop ALL heparin immediately -IV, SC, line flushes, heparin-coated catheters. Even trace amounts perpetuate the immune response.
Drug
Dose
Notes
Argatroban 1ST LINE
0.5–2 mcg/kg/min IV (no bolus). Monitor aPTT.
Hepatically cleared -preferred in renal failure. Falsely elevates INR (complicates warfarin bridging). Reduce dose in hepatic impairment, ICU, post-cardiac surgery.
Bivalirudin 1ST LINE
0.15–0.2 mg/kg/hr IV. Monitor aPTT.
Short half-life (~25 min). Preferred for PCI and cardiac surgery settings. Partially renally cleared.
Fondaparinux ALTERNATIVE
Weight-based SC (same as VTE dosing)
Pentasaccharide -does NOT cross-react with HIT antibodies. Off-label for HIT but widely used. No monitoring needed. Renally cleared -avoid if CrCl < 30.
Do NOT transfuse platelets in HIT unless life-threatening bleeding. Platelets are prothrombotic in HIT, they become activated by HIT antibodies → more thrombosis. Do NOT start warfarin until platelets recover to ≥ 150K, early warfarin in HIT can cause protein C depletion → warfarin-induced skin necrosis and venous limb gangrene. When transitioning: overlap DTI (argatroban/bivalirudin) with warfarin for ≥ 5 days AND until INR is therapeutic on two consecutive days.
🧪 Workup
Workup
4T score -pre-test probability. ≥ 6 = high probability → start non-heparin anticoagulation immediately while awaiting confirmatory testing. 4-5 = intermediate → test. ≤ 3 = low → HIT unlikely. Components: Thrombocytopenia (% fall + nadir), Timing (day 5-10), Thrombosis (new), oTher cause (none identified). [4T Score Validation, 2006]
PF4/heparin ELISA (PF4 antibody) -screening test. High sensitivity (~97%), moderate specificity (~75%). Negative ELISA essentially rules out HIT. Positive → need confirmatory test. OD > 2.0 strongly predictive.
Serotonin release assay (SRA) -confirmatory gold standard. High specificity (~95%). Takes 3-7 days to result. Functional assay -measures actual platelet activation.
CBC trend -platelet nadir typically 5-10 days after heparin exposure. Classic: > 50% drop from baseline (e.g., 250K → 80K). Nadir usually 20-80K. If < 20K → consider other diagnoses (DIC, TTP).
Bilateral lower extremity duplex US -30-50% of HIT patients have occult DVT at diagnosis even without symptoms. Screen all confirmed/suspected HIT patients.
Review ALL heparin exposure -IV drips, SQ prophylaxis, line flushes, heparin-coated catheters (dialysis, PICC lines), heparin in OR tubing. Even brief exposure counts.
Timing clues: Typical onset day 5-10. Rapid-onset HIT (< 24h) = prior heparin exposure within 100 days (pre-formed antibodies). Delayed-onset HIT = develops after heparin stopped (rare, up to 3 weeks).
💊 Medications
Medications
Drug
Dose
Route
Notes
Argatroban
2 mcg/kg/min (0.5-1.2 in liver disease)
IV drip
Direct thrombin inhibitor.Argatroban HIT Trial, 2001 Hepatically metabolized -reduce dose in liver failure. Titrate to aPTT 1.5-3× baseline. Falsely elevates INR → complicates warfarin transition.
Bivalirudin
0.15-0.25 mg/kg/hr
IV drip
Alternative DTI. Shorter half-life (25 min vs 45 min) -preferred for PCI, cardiac surgery, or renal failure. Does not elevate INR.
Fondaparinux
5-10 mg SQ daily
SQ
Factor Xa inhibitor. Off-label for HIT but widely used. No IV monitoring needed. Minimal cross-reactivity with HIT antibodies (< 1%). Renally cleared -avoid if CrCl < 30.
DO NOT use LMWH
-
-
90% in-vitro cross-reactivity with HIT antibodies. Enoxaparin, dalteparin, tinzaparin are ALL contraindicated.
Warfarin transition
Start ONLY when platelets ≥ 150K
PO
Overlap argatroban for ≥ 5 days + INR ≥ 2 for 2 consecutive days. Starting warfarin too early depletes protein C Warfarin Limb Gangrene Study, 1997 → paradoxical thrombosis (venous limb gangrene, skin necrosis). Warfarin Limb Gangrene Study, 1997
DOAC transition
Per agent dosing
PO
Rivaroxaban or apixaban increasingly used as alternatives to warfarin for long-term anticoagulation post-HIT. Start when platelets recovered. Duration: 3-6 months minimum (or longer if provoked thrombosis).
📋 On Rounds
Why can't you bridge to warfarin immediately in HIT?
Warfarin inhibits vitamin K-dependent factors (II, VII, IX, X) but also inhibits protein C and S (natural anticoagulants). Protein C has the shortest half-life (~8h) → it drops first when warfarin is started. In HIT, the patient is already in a prothrombotic state. Starting warfarin creates a transient hypercoagulable window (protein C depleted before factors drop) → venous limb gangrene and skin necrosis.
A patient on heparin has a platelet drop. How do you decide if it's HIT vs other causes?
Use the 4T score: (1) Thrombocytopenia -fall > 50% and nadir ≥ 20K scores highest, (2) Timing -days 5–10 after heparin start (or < 1 day if prior heparin in last 30 days) scores highest, (3) Thrombosis -new confirmed thrombosis scores highest, (4) oTher causes -no other explanation scores highest. 4T score 0–3 = low probability (HIT essentially ruled out, NPV > 99%). 4–5 = intermediate → send PF4 antibody.
Why can you NOT start warfarin until platelets recover above 150K in HIT?
In the acute thrombotic phase of HIT, protein C levels are already depleted (consumed by the ongoing thrombotic process). Warfarin further suppresses protein C (vitamin K-dependent, shorter half-life than other clotting factors) → transient hypercoagulable state → microvascular thrombosis → venous limb gangrene or skin necrosis.
What non-heparin anticoagulants can you use in HIT?
Argatroban (first-line): direct thrombin inhibitor, IV drip, hepatically metabolized (reduce dose in liver failure). Titrate to aPTT 1.5-3× baseline. Prolongs INR → makes warfarin transition tricky (need to check INR after holding argatroban for 4h). Bivalirudin: direct thrombin inhibitor, shorter half-life, preferred in PCI setting or renal failure (cleared by plasma proteases, not kidneys).
❓ What are the components of the 4T score?
T hrombocytopenia: > 50% fall + nadir ≥ 20K = 2pts. T iming: day 5-10 (or < 1 day with prior heparin in last 30 days) = 2pts. T hrombosis: new confirmed thrombosis = 2pts. oT her cause: none apparent = 2pts. Score: 0-3 = low (HIT unlikely), 4-5 = intermediate, 6-8 = high probability → start non-heparin anticoag immediately. [4T Score Validation, 2006]
❓ Why is warfarin dangerous if started too early in HIT?
Warfarin depletes protein C faster than procoagulant factors (protein C half-life = 6h vs Factor II = 60h). In the prothrombotic state of HIT, this early protein C drop → paradoxical thrombosis → venous limb gangrene, skin necrosis (especially at fat-rich sites). Start warfarin ONLY when platelets ≥ 150K and overlap with DTI × ≥ 5 days. Warfarin Limb Gangrene Study, 1997
❓ How do you transition from argatroban to warfarin given that argatroban elevates INR?
Argatroban (a direct thrombin inhibitor) falsely elevates INR because it affects the thrombin-dependent step in the PT assay. Strategies: (1) Start warfarin when platelets ≥ 150K while continuing argatroban. (2) Target combined INR > 4 on overlap. (3) Hold argatroban × 4 hours, then check INR -if ≥ 2, the warfarin effect is therapeutic. (4) Some centers use chromogenic Factor X assay instead (not affected by argatroban).
❓ Can you use DOACs in HIT?
DOACs (rivaroxaban, apixaban) are increasingly used as alternatives to warfarin for the ongoing anticoagulation phase after platelet recovery. Advantages: no INR monitoring, no interaction with argatroban, rapid onset. Limited prospective data but growing retrospective evidence supports safety and efficacy. Start after platelets recovered (≥ 150K). Duration: 4 weeks (HIT without thrombosis) or 3-6 months (HIT with thrombosis).
❓ What is rapid-onset HIT and how does it differ from typical HIT?
Rapid-onset HIT: platelet drop within < 24 hours of heparin re-exposure in a patient with prior heparin exposure within the last 100 days. Pre-formed PF4/heparin antibodies cause immediate platelet activation. Key clue: patient was recently hospitalized or had surgery and now presents with acute thrombocytopenia upon heparin re-exposure. Contrast with typical HIT (day 5-10 onset in heparin-naive patients).
Clinical Examples
📋 Case 1, Post-Surgical HIT with DVT
Patient: 68M, PMH HTN, DM2. POD 8 from R total knee arthroplasty on enoxaparin prophylaxis. Nursing reports new R calf swelling and pain.
Key findings: Platelets dropped from 245K to 88K (64% decline) over 3 days. Duplex US: acute R popliteal DVT. 4T score: 7 (high probability).
Management:
Stop ALL heparin products immediately (enoxaparin, flushes, line locks)
Start argatroban 2 mcg/kg/min IV, titrate to aPTT 1.5-3x baseline
Send PF4/heparin antibody (ELISA) and SRA (confirmatory)
Do NOT start warfarin until platelets ≥ 150K; overlap with argatroban ≥ 5 days
Anticoagulate for 3-6 months (HIT with thrombosis = HITT)
Teaching point: LMWH cross-reacts with HIT antibodies in ~90% of cases. A patient with HIT on UFH should NOT be switched to enoxaparin. Always use a non-heparin anticoagulant (argatroban, bivalirudin, fondaparinux).
📋 Case 2, Rapid-Onset HIT
Patient: 55F, PMH breast cancer s/p port placement 3 weeks ago (received heparin flushes). Admitted for chemo, started on UFH DVT prophylaxis. Platelets drop from 190K to 45K within 12 hours.
Key findings: Rapid platelet decline within 24h of heparin re-exposure. Prior heparin exposure < 30 days ago. 4T score: 6 (high).
Management:
Stop heparin immediately
Start argatroban; consider bivalirudin if hepatic dysfunction
Bilateral LE duplex (30-50% have occult DVT)
Send PF4 Ab + SRA
Teaching point: Rapid-onset HIT occurs within < 24h of re-exposure in patients with pre-formed antibodies from heparin exposure within the last 100 days. The 4T score timing criteria awards 2 points for platelet fall < 1 day with prior heparin exposure.
📋 Case 3, Intermediate 4T Score with Low Clinical Suspicion
Patient: 72M in MICU on UFH for AF. Day 6, platelets drop from 180K to 105K (42% decline). Patient is septic from pneumonia with new pressor requirement.
Key findings: 4T score: 4 (intermediate). Sepsis is a common cause of thrombocytopenia in the ICU. No new thrombosis.
Management:
Send PF4 antibody (ELISA) given intermediate probability
If PF4 ELISA negative (OD < 0.40) → HIT essentially excluded (NPV > 99%)
If PF4 positive → stop heparin, start argatroban, send SRA for confirmation
Consider alternative causes: sepsis-associated thrombocytopenia, drug-induced (vancomycin, linezolid), dilutional
Teaching point: The 4T score's greatest value is its NPV at low scores (0-3), which essentially rules out HIT. At intermediate scores (4-5), the PF4 ELISA helps decide next steps. Sepsis is the #1 cause of thrombocytopenia in the ICU, not HIT.
📣 Sample Presentation
One-Liner
"Mrs. Liu is a 64-year-old post-op day 7 from hip replacement on heparin prophylaxis whose platelets dropped from 220K to 82K (62% decline). No bleeding. 4T score 6 (high probability). PF4 antibody sent."
Key Points to Cover on Rounds
High-probability HIT (4T score 6: >50% drop, day 5-10 timing, no thrombosis yet, no other cause). Immediate actions: (1) ALL heparin stopped (drips, flushes, line locks), (2) argatroban started at 2 mcg/kg/min, titrate to aPTT 1.5-3× baseline, (3) bilateral LE duplex ordered (30-50% have occult DVT). PF4 Ab pending, SRA pending. No warfarin until plt >150K (protein C depletion risk → skin necrosis, venous limb gangrene). Platelet transfusion NOT indicated. Plan: argatroban until plt recovery, then transition to warfarin with ≥5 days overlap.
Monitoring
Platelet count daily -should begin recovering within 4-10 days of stopping heparin + starting alternative anticoagulation. If NOT recovering → reconsider diagnosis or check for new thrombosis.
aPTT q6h while on argatroban -target 1.5-3× baseline. Avoid supratherapeutic levels (bleeding risk).
INR for warfarin transition -argatroban falsely elevates INR. Check INR after holding argatroban × 4h to get true INR. Some centers use chromogenic factor X assay instead.
Bilateral LE duplex US at diagnosis -even if no symptoms (30-50% occult DVT)
Clinical assessment for new thrombosis daily -arterial (stroke, limb ischemia, MI) and venous (DVT, PE). HIT is a prothrombotic state -thrombosis risk highest in first 30 days.
Skin exam -skin necrosis at injection sites (heparin-induced skin necrosis occurs before overt HIT)
Duration of anticoagulation: minimum 4 weeks if HIT without thrombosis. 3-6 months if HIT with thrombosis (HIT-T). Some experts recommend extended anticoagulation for arterial HIT events.
⚡ Summary
Summary
The Platelets Drop but the Patient Clots
Anti-PF4/heparin antibodies activate platelets, so HIT is a prothrombotic state despite the thrombocytopenia.Thrombosis, not bleeding, is what harms these patients, and up to half develop it. That single fact governs every management decision on this page.
Recognize the Timing and Magnitude
A platelet fall of more than 50% from baseline, typically 5 to 10 days after heparin exposure, or within hours if there has been exposure in the previous 100 days. The nadir is usually 40,000 to 80,000, rarely below 20,000, so a profoundly low count points to another cause.
Score It With 4Ts Before Testing
Thrombocytopenia magnitude, Timing, Thrombosis or other sequelae, and oTher causes excluded.A low score has a high negative predictive value and effectively rules HIT out, which matters because the alternative anticoagulants are expensive and carry bleeding risk. Intermediate or high scores warrant testing and empiric action.
Stop All Heparin Immediately
IV, subcutaneous, line flushes, heparin-coated catheters and heparin-bonded lines.Even trace exposure perpetuates the immune response.LMWH cross-reacts and is not an alternative. Search the chart actively, because flushes and coated devices are the exposures that get missed.
Stopping Is Not Enough: Start a Non-Heparin Anticoagulant
Argatroban or bivalirudin, or fondaparinux in selected patients.Simply withholding heparin leaves an untreated prothrombotic state, and thrombosis continues to develop. Argatroban is hepatically cleared, so it is the choice in renal failure, and it prolongs the INR, which complicates later warfarin transition.
Do Not Start Warfarin Until Platelets Recover
Wait until the count is at or above 150,000.Early warfarin depletes protein C faster than the procoagulant factors, causing venous limb gangrene and skin necrosis in a patient who is already hypercoagulable. Overlap with the non-heparin agent for at least 5 days and until the INR is therapeutic.
Do Not Transfuse Platelets
Unless there is life-threatening bleeding. Transfused platelets are activated by the HIT antibodies and add fuel to the thrombosis. The low count is not the problem; the clotting is.
Confirm, Document and Duration
Screen with an immunoassay (sensitive, not specific) and confirm with a functional assay such as the serotonin release assay, which is what distinguishes true HIT from the common asymptomatic antibody. Anticoagulate for at least 4 weeks without thrombosis and 3 months with it.Label the allergy prominently in the record, since re-exposure years later can cause rapid-onset HIT and the patient will not know to warn anyone.
RoundsRx Infographic Series · #82 · Hematology · PDF 153 KB
Text version
Hematology · One Pager
HIT -Heparin-Induced Thrombocytopenia
4T score ≥ 6 → stop ALL heparin + start argatroban. Bilateral LE duplex (30-50% occult DVT). No warfarin until plt ≥ 150K. No LMWH (90% cross-reactivity).
🧪 Diagnosis
4T score: Thrombocytopenia > 50% fall, Timing days 5-10, Thrombosis, oTher causes excluded. Score ≥ 6 = high probability → treat immediately. Send PF4 Ab + SRA.
🚨 Treatment
STOP all heparin (drips, flushes, line locks). Start argatroban 2 mcg/kg/min IV (reduce in liver failure). Bilateral LE duplex US (30-50% have occult DVT).
⚠️ Warfarin Rules
Do NOT start until plt ≥ 150K (protein C depletion → venous limb gangrene). Overlap argatroban ≥ 5 days. DOACs emerging as option after acute phase but limited evidence.
💊 Key Drugs
Argatroban2 mcg/kg/min IV drip
BivalirudinAlternative DTI
FondaparinuxSQ (off-label for HIT)
NO LMWH90% cross-reactivity
⚠️ Pitfalls
Not stopping ALL heparin (including flushes and line locks)
Warfarin before plt ≥ 150K (limb gangrene risk)
LMWH for HIT (cross-reacts in 90%)
Not checking bilateral LE duplex (30-50% occult DVT)
Fever (≥ 38.3°C single or ≥ 38.0°C sustained ≥ 1h) + ANC < 500 (or expected to drop < 500). This is a medical emergency -antibiotics within 60 minutes. These patients can go from febrile to septic shock in hours because they have no immune defense.
🔍 Overview
Definition
Neutropenia: ANC < 500 cells/μL, or ANC < 1000 and expected to decline to < 500 within 48h
Fever: single temperature ≥ 38.3°C (101°F) OR sustained ≥ 38.0°C (100.4°F) for ≥ 1 hour
Profound neutropenia: ANC < 100 → highest risk of bacteremia and death
Neutropenic patients cannot mount a normal inflammatory response. They may have no localizing signs -no pus, no infiltrate on CXR (no neutrophils to create one), minimal erythema at infection site. Fever may be the ONLY sign of life-threatening infection.
Risk Stratification -MASCC Score -low- vs high-risk febrile neutropenia (≥21 = low risk, may be eligible for outpatient oral antibiotics)
MASCC (Multinational Association for Supportive Care in Cancer) score predicts low-risk vs high-risk for serious complications.
Criterion
Points
Burden of illness: mild or no symptoms
+5
Burden of illness: moderate symptoms
+3
No hypotension (SBP ≥ 90)
+5
No COPD
+4
Solid tumor or no prior fungal infection
+4
No dehydration requiring IV fluids
+3
Outpatient at onset of fever
+3
Age < 60
+2
Score ≥ 21: low risk (~5% serious complication rate) → may consider outpatient oral antibiotics if reliable follow-up. Score < 21: high risk → admit for IV antibiotics.
Workup
Blood cultures × 2 sets (one from each lumen if central line + one peripheral). Draw BEFORE antibiotics but do NOT delay antibiotics for culture results.
CBC with differential, BMP, LFTs, lactate
UA + urine culture
CXR (may be falsely negative -no neutrophils to create infiltrate)
Sputum culture if productive cough
Stool for C. diff if diarrhea
Consider CT chest if pulmonary symptoms (CXR insensitive in neutropenia)
Time to antibiotics matters. Start within 60 minutes of presentation. Mortality increases with every hour of delay.
Setting
Regimen
Notes
Standard empiric
Cefepime (Maxipime) 2g IV q8h 1ST LINE
Or piperacillin-tazobactam 4.5g IV q6h or meropenem 1g IV q8h. Anti-pseudomonal coverage is essential. Monotherapy is sufficient for uncomplicated cases IDSA, 2010.
Add vancomycin if:
Vancomycin (Vancocin) 15–20 mg/kg IV q8–12h
Hemodynamic instability, skin/soft tissue infection, catheter-site infection, known MRSA colonization, severe mucositis, PNA on imaging. Do NOT add vanc routinely -only for specific indications.
Add antifungal if:
Micafungin (Mycamine) 100 mg IV daily or voriconazole or liposomal amphotericin B
Persistent fever after 4–7 days of antibiotics with no identified source. Prolonged neutropenia (> 7 days). Consider CT chest for invasive aspergillosis (halo sign). Galactomannan, β-D-glucan.
Low-risk outpatient
Ciprofloxacin (Cipro) 750 mg PO BID + amoxicillin-clavulanate (Augmentin) 875 mg PO BID
Only if MASCC ≥ 21, reliable patient, close follow-up within 24h, no IV line infection. Must observe 4–6h first.
G-CSF (Filgrastim/Neupogen)
NOT routine in all neutropenic fever -per ASCO/IDSA, G-CSF is considered for: pneumonia, sepsis/septic shock, fungal infection, expected prolonged neutropenia (> 10 days), ANC < 100
Dose: filgrastim 5 mcg/kg SC daily until ANC recovery
🧪 Workup
Workup
Blood cultures × 2 sets -1 peripheral + 1 from each lumen of central line. Draw BEFORE antibiotics. If no central line, 2 peripheral sets from different sites.
CBC with differential -confirm ANC < 500/μL (or < 1000 and expected to decline). Trend for nadir timing.
BMP + LFTs -baseline renal/hepatic function for antibiotic dosing
Lactate -if any concern for sepsis (tachycardia, hypotension)
CXR -may be NORMAL even with pneumonia (neutropenic patients cannot mount an inflammatory infiltrate). A normal CXR does NOT exclude pulmonary infection.
UA + urine culture -but note: pyuria may be absent (no WBCs to form pus)
Skin exam -inspect ALL skin including perianal area, line sites, oral mucosa. Cellulitis without pus/erythema is common in neutropenia.
Stool studies -C. diff PCR if diarrhea (mucositis + antibiotics = high risk)
CT chest -if persistent fever day 4-5 despite antibiotics. Look for halo sign (invasive aspergillosis).
Galactomannan + β-D-glucan -at day 4-5 if fevers persist (fungal biomarkers). Galactomannan specific for Aspergillus. β-D-glucan broad (not Mucor/Crypto).
MASCC score -risk stratification for outpatient vs inpatient management (≥ 21 = low risk → may consider oral FQ + amoxicillin-clav)
💊 Medications
Medications
Drug
Dose
Route
Notes
Cefepime
2g IV q8h
IV
First-line anti-pseudomonal β-lactam. Start within 1 hour of presentation. IDSA, 2010
Meropenem
1g IV q8h
IV
Alternative if prior ESBL, cefepime allergy, or hemodynamic instability. Also covers anaerobes.
Pip-tazo
4.5g IV q6h
IV
Alternative first-line. Covers Pseudomonas + anaerobes. Avoid if concern for seizures (piperacillin lowers threshold).
Vancomycin
15-20 mg/kg IV
IV
NOT routine. Add ONLY if: hemodynamic instability, skin/soft tissue infection, suspected line infection, known MRSA colonization, severe mucositis, or blood culture growing GP cocci.
Micafungin
100 mg IV daily
IV
Empiric antifungal at day 4-5 if fever persists despite antibiotics. Echinocandin covers Candida + Aspergillus.
Voriconazole
6 mg/kg q12h × 2 → 4 mg/kg q12h
IV/PO
If invasive aspergillosis suspected (halo sign on CT, positive galactomannan). Voriconazole Aspergillosis Trial, 2002
G-CSF (filgrastim)
5 mcg/kg SQ daily
SQ
Consider if ANC expected to be < 100 for > 10 days, pneumonia, sepsis, or invasive fungal infection. Not routine for uncomplicated neutropenic fever.
Levofloxacin + Amox-clav
750 mg daily + 875 mg BID
PO
Outpatient option for LOW-RISK patients only (MASCC ≥ 21, expected short neutropenia, no comorbidities).
📋 On Rounds
Why can the CXR be falsely normal in neutropenic pneumonia?
Infiltrates on CXR are caused by neutrophilic inflammation -exudate, pus, and cellular debris filling the alveoli. Without neutrophils (ANC < 500), the patient cannot mount this inflammatory response, so the infection exists but there's nothing to create a visible infiltrate. As the ANC recovers, the infiltrate may suddenly "appear" -this doesn't mean the infection is getting worse, it means the immune system is now responding.
When do you add vancomycin to neutropenic fever empiric coverage?
NOT routinely. IDSA guidelines recommend adding vancomycin only for specific indications: (1) hemodynamic instability/septic shock, (2) suspected catheter-related infection (tunnel infection, port-site cellulitis), (3) known MRSA colonization, (4) skin/soft tissue infection, (5) severe mucositis with fluoroquinolone prophylaxis (risk of viridans strep bacteremia).
When do you add vancomycin to cefepime in neutropenic fever?
Vancomycin is NOT routine first-line -add only for specific indications: (1) Hemodynamic instability / septic shock, (2) Suspected catheter-related infection (line erythema, tunnel infection, positive line cultures), (3) Skin/soft tissue infection (cellulitis, wound), (4) Blood culture growing gram-positive cocci (pending identification), (5) Mucositis (severe -increases risk of viridans strep bacteremia, which can cause septic shock).
What is the MASCC score and how does it guide management?
MASCC (Multinational Association for Supportive Care in Cancer) score stratifies neutropenic fever risk. Points for: burden of illness (5 or 3), no hypotension (5), no COPD (4), solid tumor or no prior fungal infection (4), no dehydration (3), outpatient onset (3), age < 60 (2). Score ≥ 21: low risk (~5% serious complications) → candidate for outpatient oral antibiotics (ciprofloxacin + amox-clav)
❓ What is the MASCC score and when do you use it?
The MASCC score risk-stratifies neutropenic fever patients. Score ≥ 21 = low risk (may consider outpatient oral antibiotics: levofloxacin + amoxicillin-clavulanate). Criteria include: burden of illness, no hypotension, no COPD, solid tumor (vs hematologic), no dehydration, outpatient at onset, and age < 60.
❓ When do you add vancomycin to empiric therapy in neutropenic fever?
Vancomycin is NOT routine. Add only for: (1) hemodynamic instability/sepsis, (2) skin/soft tissue infection or suspected line infection, (3) blood cultures growing gram-positive cocci pending speciation, (4) known MRSA colonization, (5) severe mucositis (fluoroquinolone prophylaxis setting). IDSA, 2010
❓ At what point do you add empiric antifungal therapy?
At day 4-5 if fever persists despite broad-spectrum antibiotics. Start echinocandin (micafungin 100 mg daily). Send galactomannan + β-D-glucan. CT chest looking for halo sign (invasive aspergillosis). If CT or galactomannan positive → switch to voriconazole (better CNS penetration for Aspergillus). Voriconazole Aspergillosis Trial, 2002
❓ Name three organisms neutropenic patients are particularly susceptible to.
Pseudomonas aeruginosa (gram-negative, most feared -drives anti-pseudomonal empiric therapy), Aspergillus (invasive pulmonary aspergillosis in prolonged neutropenia > 10 days), and Candida (especially with mucositis, central lines, broad-spectrum antibiotics). Also viridans group streptococci in severe mucositis.
❓ Why can a CXR be normal in a neutropenic patient with pneumonia?
Neutropenic patients cannot mount an adequate inflammatory response. Pulmonary infiltrates require neutrophil recruitment to the infection site. With ANC < 500, there are insufficient neutrophils to form the inflammatory exudate that creates the radiographic infiltrate. The infiltrate may "appear" on CXR as neutrophils recover -this is why some patients develop new infiltrates during count recovery.
❓ What is the role of G-CSF (filgrastim) in neutropenic fever?
G-CSF is NOT routine for uncomplicated neutropenic fever. Consider in: (1) ANC expected < 100 for > 10 days, (2) pneumonia, (3) sepsis/septic shock, (4) invasive fungal infection, (5) age > 65. Prophylactic G-CSF is indicated for chemo regimens with ≥ 20% risk of febrile neutropenia. [ASCO/NCCN Guidelines]
Clinical Examples
📋 Case 1, Straightforward Neutropenic Fever
Patient: 62M with AML on induction chemotherapy (7+3), day 12 post-chemo. Presents with fever 39.1C, no localizing symptoms. ANC 40.
Key findings: HR 102, BP 128/74, SpO2 97%. No oral mucositis, no line erythema, no skin lesions. CXR clear. UA bland. MASCC score 18 (high risk).
Management:
Blood cultures x2 (1 peripheral + 1 from central line) BEFORE antibiotics
Cefepime 2g IV q8h started within 60 minutes of fever onset
No vancomycin (no hemodynamic instability, no line infection, no skin findings)
Daily reassessment: add vancomycin if clinical deterioration, antifungal at day 4-5 if persistent fever
Continue cefepime until ANC > 500 and afebrile ≥ 48h
Teaching point: Cefepime monotherapy is sufficient for uncomplicated neutropenic fever. Adding vancomycin empirically increases VRE selection and nephrotoxicity without improving outcomes. IDSA Guidelines, 2010
📋 Case 2, Neutropenic Fever with Line Infection
Patient: 45F with NHL on R-CHOP cycle 3, ANC 120. Fever 38.5C with rigors after PICC line flush. Erythema and tenderness at PICC insertion site.
Key findings: HR 115, BP 98/58. Tunnel erythema along PICC tract. Blood cultures drawn: differential time to positivity pending.
Blood cultures from PICC AND peripheral, differential time to positivity > 2h = line infection
Consult ID for line removal vs salvage (tunnel infection usually requires removal)
NS bolus 30 mL/kg for hypotension
Teaching point: Vancomycin is added to neutropenic fever ONLY for specific indications: line infection, hemodynamic instability, skin/soft tissue infection, gram-positive bacteremia, or severe mucositis. De-escalate at 48-72h if cultures negative for gram-positives.
📋 Case 3, Persistent Fever Requiring Antifungal Escalation
Patient: 58M with AML, ANC 0, day 5 of cefepime for neutropenic fever. Still febrile (38.8C daily). Blood cultures negative. No source identified.
Key findings: CT chest: new 1.5 cm nodule with surrounding ground-glass halo ("halo sign"). Galactomannan index 1.8 (positive). Beta-D-glucan 245 (elevated).
Management:
Start voriconazole 6 mg/kg IV q12h x2 doses (loading), then 4 mg/kg IV q12h
Check voriconazole trough at day 5 (target 1-5.5 mcg/mL)
Continue cefepime for bacterial coverage
Consider G-CSF (ANC 0 for > 10 days with invasive fungal infection)
Repeat CT chest in 1-2 weeks to assess response
Teaching point: Persistent fever at day 4-5 on broad-spectrum antibiotics triggers empiric antifungal therapy. The halo sign on CT suggests invasive aspergillosis. Voriconazole is preferred over amphotericin B. Herbrecht et al., 2002
📣 Sample Presentation
One-Liner
"Mr. Wilson is a 58-year-old with AML on induction chemotherapy, day 10 post-chemo, ANC 80, presenting with fever 38.8°C. Hemodynamically stable. MASCC score 21 (high risk)."
Key Points to Cover on Rounds
Neutropenic fever -ANC 80 (profound neutropenia). Blood cultures × 2 drawn (1 peripheral + 1 from PICC). Cefepime 2g IV q8h started within 45 min of fever. No vancomycin yet (no hemodynamic instability, no line erythema, no skin infection). Chest CT: no infiltrate. UA: no pyuria. No oral mucositis. Source: occult bacteremia until proven otherwise. Plan: daily assessment -add vancomycin if clinical deterioration or positive cultures with GP. Add antifungal (micafungin) if fever persists at day 4-5. Continue cefepime until ANC >500 + afebrile ≥48h.
Monitoring
Temperature curve -defervescence expected within 3-5 days on appropriate antibiotics. Persistent fever at day 4-5 = expand workup (CT chest, fungal markers, line cultures)
ANC daily -recovery above 500/μL is the key milestone. Antibiotics generally continued until ANC > 500 AND afebrile × 48h.
Blood cultures at 48h -if initial cultures positive, repeat to document clearance. If persistent bacteremia → evaluate for endovascular source, line removal.
A single temperature of 38.3°C, or 38.0°C sustained for an hour, with an ANC below 500 or expected to fall below 500.This is a medical emergency: these patients can go from febrile to septic shock within hours because they have no cellular defense.
Antibiotics Within 60 Minutes
Blood cultures from a peripheral site and from every lumen of any central line, then antibiotics.Mortality rises with every hour of delay, so the antibiotic goes in before imaging, before the source is known, and before the culture results exist. Do not let a CT scan or a line placement delay the first dose.
Expect No Localizing Signs
Neutropenic patients cannot mount an inflammatory response.No pus, no infiltrate on the chest film (there are no neutrophils to make one), minimal erythema at an infected site.Fever may be the only sign of life-threatening infection, and a reassuring examination is not reassurance.
Antipseudomonal Monotherapy Is the Backbone
Cefepime, piperacillin-tazobactam or meropenem.Pseudomonas is the organism that kills fastest, which is why coverage is mandatory even without evidence of it. Do not add an aminoglycoside routinely: it adds nephrotoxicity without improving outcomes in uncomplicated cases.
Add Vancomycin Only for Specific Reasons
Hemodynamic instability, a suspected catheter-related infection, skin or soft tissue infection, pneumonia, known MRSA colonization, or a positive gram-positive culture pending speciation.Routine empiric vancomycin does not improve survival and drives resistance and nephrotoxicity. Stop it at 48 to 72 h if no gram-positive organism is isolated.
Examine the Places That Hide Infection
Mouth and pharynx, skin and every line site, and the perianal area.Do not perform a digital rectal examination and do not use rectal thermometers or suppositories: they can seed bacteremia through friable mucosa. Look, but do not instrument.
Escalate for Persistent Fever
Fever persisting beyond 4 to 7 days on broad-spectrum antibiotics means add antifungal cover (an echinocandin or liposomal amphotericin), and image the chest and sinuses looking for invasive mold. Reassess the whole picture rather than simply broadening again: consider line infection, abscess, C. difficile, drug fever and typhlitis.
Risk-Stratify and Use G-CSF Selectively
MASCC 21 or above identifies low-risk patients who may be treated as outpatients with oral ciprofloxacin plus amoxicillin-clavulanate, given reliable follow-up. G-CSF is for prophylaxis in high-risk regimens, not as routine treatment of established neutropenic fever, where it shortens neutropenia without changing mortality. Continue antibiotics until the ANC recovers above 500 and is rising and the patient is afebrile.
RoundsRx Infographic Series · #113 · Oncology & Palliative · PDF 150 KB
Text version
Oncology / ID · One Pager
Neutropenic Fever
ANC < 500 + fever → cefepime within 1 hour. No vancomycin unless specific indication. Add antifungal at day 4-5 if persistent fever. MASCC ≥ 21 may go home.
🧪 Definition
ANC < 500 (or expected to fall to < 500) + single temp ≥ 38.3°C or sustained ≥ 38.0°C over 1 hour. Medical emergency -clock starts at fever.
🚨 Treatment
Cefepime 2g IV q8h started within 1 hour. Blood cultures × 2 (peripheral + from line). CXR. UA. No vancomycin unless: shock, skin/line infection, GP bacteremia, mucositis.
💊 Escalation
Add vancomycin if specific indication at any time. Add antifungal (micafungin/caspofungin) at day 4-5 if persistent fever. MASCC ≥ 21: low-risk → outpatient oral abx (cipro + amox-clav) if reliable.
💊 Key Drugs
Cefepime2g IV q8h
Meropenem1g q8h (if prior resistant GNR)
Vancomycin15-20 mg/kg (only if indicated)
Micafungin100 mg daily (persistent fever)
⚠️ Pitfalls
Delaying cefepime (start within 1 hour)
Routine vancomycin (not needed unless specific indication)
Missing perianal abscess (physical exam including perirectal)
Thyroid storm: life-threatening thyrotoxicosis with mortality 10–30% even with treatment. Myxedema coma: severe hypothyroidism with altered consciousness and hypothermia. Both are clinical diagnoses -don't wait for labs to treat.
🔥 Thyroid Storm
Recognition -Burch-Wartofsky Score ≥ 45 -clinical probability of thyroid storm (≥45 highly suggestive, 25–44 impending, <25 unlikely)
Thyrotoxicosis with end-organ dysfunction: high fever, tachycardia out of proportion, AMS, HF, liver failure. Usually triggered by: infection, surgery, trauma, iodine load (contrast), medication non-adherence.
Treat in this order. Iodine must come AFTER thionamide (≥ 1h later) -otherwise iodine provides substrate for MORE thyroid hormone production (Jod-Basedow effect).
Step
Drug
Dose
Mechanism
1. Block synthesis
PTU PREFERRED
500–1000 mg PO loading → 250 mg PO q4h
Blocks new thyroid hormone synthesis (inhibits TPO). PTU preferred over methimazole in storm because it also inhibits peripheral T4→T3 conversion.
2. Block release (≥ 1h after PTU)
Iodine (SSKI or Lugol's)
SSKI 5 drops PO q6h, or Lugol's 10 drops PO q8h
Wolff-Chaikoff effect -high iodine temporarily shuts down thyroid hormone release. MUST give after thionamide or iodine becomes fuel.
3. Block peripheral effects
Propranolol
60–80 mg PO q4h (or 1 mg IV slowly)
β-blockade controls tachycardia, tremor, agitation. Propranolol also blocks T4→T3 conversion. Esmolol drip if too unstable for PO.
4. Block conversion
Hydrocortisone (Solu-Cortef)
100 mg IV q8h
Blocks peripheral T4→T3 conversion. Also treats possible concomitant adrenal insufficiency (thyroid storm increases cortisol metabolism). Also: dexamethasone 2 mg IV q6h is alternative.
5. Supportive
Cooling, IVF, acetaminophen
As needed
Avoid aspirin -displaces T4 from TBG → increases free T4. Use acetaminophen for fever. ICU admission. Treat precipitant.
❄️ Myxedema Coma
Recognition
Altered mental status (lethargy → coma) in the setting of severe hypothyroidism
Hypothermia (may be < 35°C -core temp may not register on standard thermometer)
200–400 mcg IV loading dose → 1.6 mcg/kg/day IV (50–100 mcg/day)
IV required -GI absorption unreliable in myxedema (ileus, edema). Large loading dose to replenish depleted T4 stores.
IV T3 (liothyronine) CONTROVERSIAL
5–20 mcg IV loading → 2.5–10 mcg IV q8h
Faster onset than T4 (T4 takes days to convert). Some add T3 for severe cases. Risk: arrhythmia, cardiac ischemia (especially elderly/CAD). No RCT showing mortality benefit.
Hydrocortisone (Solu-Cortef) GIVE BEFORE T4
100 mg IV q8h
Must give stress-dose steroids BEFORE thyroid hormone. Hypothyroidism masks adrenal insufficiency -giving T4 increases metabolic rate → unmasks cortisol deficiency → adrenal crisis. Always give hydrocortisone first, taper once adrenal axis confirmed normal.
Supportive: passive rewarming only (active rewarming causes vasodilation → cardiovascular collapse). Avoid sedatives/opioids (blunt already-depressed respiratory drive). Intubate if hypoventilating. Treat hyponatremia cautiously (fluid restrict, may need hypertonic saline if symptomatic). Treat precipitant.
📋 On Rounds
Why must iodine come AFTER the thionamide in thyroid storm?
Iodine is the substrate for thyroid hormone synthesis. If you give iodine to a thyrotoxic gland without first blocking the synthesis machinery (TPO enzyme), the gland uses the iodine to produce even more T3/T4 -the Jod-Basedow phenomenon. The thionamide (PTU or methimazole) blocks TPO first, ensuring the gland cannot use the incoming iodine for new hormone synthesis.
Why give steroids before thyroid hormone in myxedema coma?
Hypothyroidism slows cortisol metabolism, so the body's cortisol "lasts longer" and masks underlying adrenal insufficiency. When you give T4 and increase the metabolic rate, cortisol is suddenly metabolized faster → cortisol drops → adrenal crisis (hypotension, shock, death). Up to 5–10% of myxedema patients have concomitant adrenal insufficiency (Schmidt syndrome -autoimmune polyglandular syndrome).
Why do you give iodine 1 HOUR AFTER PTU and not at the same time?
Why do you give hydrocortisone in thyroid storm even without adrenal insufficiency?
Two reasons: (1) Thyroid storm increases cortisol metabolism -the hypermetabolic state accelerates cortisol clearance, creating a state of relative adrenal insufficiency. The adrenals can't keep up with demand. Without supplementation → adrenal crisis → refractory hypotension. (2) Hydrocortisone blocks peripheral T4 → T3 conversion (same enzyme that PTU and propranolol block -deiodinase type 1).
Why must you give PTU BEFORE iodine in thyroid storm?
Iodine is a substrate for new thyroid hormone synthesis. If given before blocking synthesis with a thionamide, it feeds the storm (Jod-Basedow effect). Always give PTU ≥ 1 hour before SSKI/Lugol's.
Why is aspirin contraindicated in thyroid storm?
Aspirin displaces T4 from thyroid-binding globulin (TBG), acutely increasing free T4 levels and worsening the storm. Use acetaminophen for fever instead.
Name 3 drugs that block T4→T3 peripheral conversion.
PTU, propranolol (high-dose), and corticosteroids. This is why all three are part of the thyroid storm treatment protocol. Methimazole does NOT block peripheral conversion.
What is the Burch-Wartofsky score and when do you use it?
A scoring system using temperature, CNS effects, GI dysfunction, HR, CHF, and AF to diagnose thyroid storm. Score ≥ 45 = thyroid storm, 25-44 = impending storm. Lab values alone can't distinguish thyrotoxicosis from storm.
Clinical Examples
📋 Case 1, Graves' Disease with Surgical Trigger
Patient: 34F, known Graves disease (non-adherent to methimazole x 3 weeks), presents post-emergency appendectomy with fever 40.2°C, HR 168, agitation, tremor, and vomiting.
Key findings: BP 160/70, RR 28, T 40.2°C. TSH < 0.01, free T4 6.8 (normal 0.8-1.8). Burch-Wartofsky score 60. Diffuse goiter with bruit. New atrial fibrillation on telemetry.
Acetaminophen for fever (NOT aspirin, displaces T4 from TBG)
ICU admission, cooling blankets, aggressive IV fluids
Teaching point: The order of therapy is critical: thionamide FIRST (block synthesis), then iodine ≥ 1 hour later (block release). Giving iodine before blocking synthesis fuels more hormone production (Jod-Basedow phenomenon). ATA Guidelines, 2016
📋 Case 2, Thyroid Storm Mimicking Sepsis
Patient: 52F, no known thyroid history, presents with fever 39.5°C, tachycardia to 150, confusion, and diarrhea. Initially treated as sepsis with broad-spectrum antibiotics, but cultures negative at 48h.
Key findings: Weight loss of 20 lbs over 3 months (per family). Fine tremor, lid lag, exophthalmos. TSH < 0.005, free T4 8.2, free T3 22. Burch-Wartofsky 55. LFTs elevated (AST 180, ALT 145, thyroid hepatopathy).
Continue antibiotics until infection definitively ruled out (storm can coexist with sepsis)
Monitor LFTs closely, hepatic dysfunction is a poor prognostic indicator in thyroid storm
Avoid esmolol in decompensated patients; propranolol preferred (also blocks T4→T3)
Teaching point: Thyroid storm and sepsis share many features (fever, tachycardia, AMS, hypotension). Always check TSH in unexplained tachycardia or sepsis not responding to antibiotics. Liver failure in thyroid storm carries mortality > 50%.
📋 Case 3, Amiodarone-Induced Thyrotoxicosis
Patient: 68M, on amiodarone for AF x 2 years, presents with worsening AF with RVR (HR 142), weight loss, and anxiety. Previously well-controlled.
Key findings: TSH < 0.01, free T4 4.8. No goiter, no exophthalmos. CRP 45. Thyroid ultrasound: normal-sized gland with decreased vascularity.
Prednisone 40 mg daily (first-line for type 2 AIT)
Type 1 (excess iodine substrate) would get thionamide + potassium perchlorate
If unclear type 1 vs 2, treat both simultaneously (combined PTU + prednisone)
Discuss with cardiology whether to stop amiodarone (long half-life of 40-55 days)
Teaching point: Amiodarone contains 37% iodine by weight. Type 1 AIT occurs in patients with underlying thyroid disease, excess substrate. Type 2 occurs in normal glands, direct thyroid destruction. Doppler ultrasound vascularity helps distinguish: increased = type 1, decreased/absent = type 2. ETA Guidelines, 2018
📣 Sample Presentation
One-Liner
"Ms. Santos is a 32-year-old with known Graves disease (non-adherent to methimazole) presenting with fever 39.8°C, HR 162, agitation, and tremor after a dental extraction. TSH <0.01, free T4 7.8. Burch-Wartofsky score 55. Thyroid storm."
Key Points to Cover on Rounds
Thyroid storm (BW score 55, ≥45 = storm). Precipitant: dental surgery + medication non-adherence. Treatment ORDER matters: (1) PTU 200 mg PO/PR q4h (blocks synthesis + peripheral T4→T3 conversion), (2) SSKI (iodine) started 1 HOUR AFTER first PTU dose (blocks thyroid hormone release -Wolff-Chaikoff), (3) propranolol 60 mg PO q6h (symptom control + blocks T4→T3), (4) hydrocortisone 100 mg IV q8h (prevents adrenal crisis + blocks conversion), (5) acetaminophen for fever (NOT aspirin -displaces T4 from binding proteins). ICU. Cooling blankets. IV fluids.
🔍 Overview
Overview
Thyroid storm is a life-threatening exaggeration of thyrotoxicosis with multi-organ dysfunction. Mortality 10-30% even with treatment. Diagnosis is clinical -do not wait for labs. Use the Burch-Wartofsky Point Scale (BWPS): score ≥ 45 = thyroid storm, 25-44 = impending storm. Classic triggers: surgery, infection, trauma, iodinated contrast, medication non-compliance, DKA in a patient with underlying Graves' disease. Key features: fever > 104°F (40°C), tachycardia out of proportion, altered mental status, GI dysfunction (diarrhea, jaundice -liver failure is a poor prognostic sign). Treatment follows a specific order: (1) beta-blocker → (2) thionamide → (3) iodine (≥ 1h after thionamide) → (4) steroids → (5) supportive care. The delay of iodine after thionamide is critical -giving iodine first fuels more hormone synthesis (Jod-Basedow effect).
🧪 Workup
Workup
TSH + free T4 + free T3 -TSH suppressed (< 0.01), T4/T3 elevated. T3 often disproportionately high.
ECG -AF in 10-35% of thyroid storm. Look for rate, ischemia.
Pregnancy test -in women of childbearing age (PTU preferred in 1st trimester)
⚡ Management
Management
Order of treatment matters: (1) Thionamide first → (2) Iodine 1 hour later → (3) Beta-blocker → (4) Steroids → (5) Supportive. Never give iodine before thionamide (Jod-Basedow effect -iodine feeds the storm).
1. Block new hormone synthesis: PTU 200 mg PO/PR q4h (preferred -also blocks T4→T3 conversion) or methimazole 20 mg PO q4-6h
2. Block hormone release (1h after thionamide): SSKI 5 drops q6h or Lugol's iodine 10 drops q8h. Lithium 300 mg q8h if iodine allergic.
3. Block peripheral effects: Propranolol 60-80 mg PO q4h (also blocks T4→T3) or esmolol drip if can't take PO
Step 1 -Block new hormone synthesis: PTU 500-1000mg loading → 250mg q4h (preferred over methimazole in storm because PTU also blocks T4→T3 conversion). Give rectally if vomiting.
Step 2 -Block hormone RELEASE (give ≥1 hour AFTER PTU): SSKI 5 drops q6h or Lugol's iodine 10 drops q8h. If given BEFORE antithyroid drugs, iodine will fuel more hormone production (Jod-Basedow effect).
Step 3 -Block peripheral T4→T3 conversion: Hydrocortisone (Solu-Cortef) 100mg IV q8h (also treats possible relative adrenal insufficiency).
Step 4 -Block peripheral effects: Propranolol (Inderal) 60-80mg PO q4-6h (preferred β-blocker -also inhibits T4→T3 conversion). Use esmolol drip if unable to take PO or hemodynamically tenuous.
Supportive: Cooling blankets for fever (avoid aspirin -displaces T4 from binding proteins), IV fluids, acetaminophen. ICU admission.
Key: Mortality of untreated thyroid storm is 20-30%. The sequential approach (PTU first, THEN iodine) is critical.
Alternative. More potent per mg. Does NOT block T4→T3. Preferred long-term but PTU preferred in storm and 1st trimester.
SSKI
5 drops q6h
PO
Give ≥ 1h AFTER thionamide. Blocks hormone release (Wolff-Chaikoff effect).
Propranolol
Burch-Wartofsky, 1993 60-80 mg PO q4h
PO
Non-selective BB. Also inhibits T4→T3 conversion at high doses. Controls tachycardia, tremor, diaphoresis.
Esmolol
500 mcg/kg bolus → 50-200 mcg/kg/min
IV
If can't take PO or hemodynamically unstable. Ultra-short acting.
Hydrocortisone
ATA, 2016 100 mg IV q8h
IV
Blocks T4→T3. Treats relative adrenal insufficiency. Empiric in all storm patients.
Cholestyramine
4g PO QID
PO
Adjunctive -binds thyroid hormone in gut, interrupts enterohepatic circulation.
Acetaminophen
1g IV/PO q6h
IV/PO
Antipyretic. NOT aspirin (displaces T4 from TBG).
⚡ Summary
Summary
It Is a Clinical Diagnosis
Do not wait for the thyroid function tests to treat.Mortality is 10 to 30% even with treatment. Look for fever, tachycardia out of proportion, agitation or delirium, heart failure and prominent GI symptoms in a thyrotoxic patient. The lab values do not distinguish storm from uncomplicated hyperthyroidism; the clinical picture does.
The Order of Drugs Matters
Thionamide first, then iodine at least 1 hour later.Iodine given first supplies substrate for more hormone synthesis (the Jod-Basedow effect), which makes the storm worse. This is the single most important sequencing rule in endocrine emergencies.
Block Synthesis, Release, Conversion and Effect
PTU 500 to 1,000 mg load then 250 mg q4h, preferred over methimazole here because it also blocks peripheral T4 to T3 conversion. Then SSKI or Lugol iodine to block release. Propranolol for the adrenergic effects and additional conversion blockade. Hydrocortisone 100 mg IV q8h, which blocks conversion and covers the relative adrenal insufficiency of severe thyrotoxicosis.
Do Not Give Aspirin
It displaces T4 from thyroid-binding globulin, raising free T4 and worsening the storm.Use acetaminophen for fever, plus cooling blankets. This is a small detail that is frequently missed on a ward where aspirin is the reflex antipyretic.
Hunt and Treat the Precipitant
Infection, surgery, trauma, iodinated contrast, amiodarone, childbirth, DKA, or abrupt withdrawal of antithyroid drugs.Storm almost never happens without a trigger, so treating the thyroid without finding the precipitant leaves the patient half-treated.
Support the Heart Aggressively
High-output heart failure and atrial fibrillation are common, and the tachycardia is what drives the decompensation. Use beta blockade carefully in overt heart failure, favoring a short-acting agent such as esmolol so it can be withdrawn, and treat the failure conventionally alongside. Aggressive fluids for the insensible and GI losses, and glucose support for the hypermetabolic state.
Myxedema Coma Is the Mirror Image
Hypothermia, altered mental status and a precipitant in an untreated hypothyroid patient.Hydrocortisone goes in before or with the thyroid hormone, because T4 raises cortisol demand and precipitates adrenal crisis if the axis is impaired. Then levothyroxine 200 to 400 mcg IV load, intravenously because gut absorption is unreliable.
Two Supportive Rules in Myxedema Coma
Passive rewarming only: active external rewarming causes peripheral vasodilation and cardiovascular collapse in a patient with no reserve. Avoid sedatives and opioids, which blunt an already depressed respiratory drive, and intubate for hypoventilation and CO₂ retention. Correct the hyponatremia slowly, since overcorrection risks osmotic demyelination.
PTU before iodine: iodine without PTU → substrate for MORE T3/T4 synthesis. Aspirin displaces T4 from TBG → increases free T4 → worsens storm. Hydrocortisone: relative adrenal insufficiency in hypermetabolic state.
💊 Key Drugs
PTU200 mg PO/PR q4h
SSKI5 drops q6h (1h after PTU)
Propranolol60-80 mg PO q6h
Hydrocortisone (Solu-Cortef)100 mg IV q8h
⚠️ Pitfalls
Iodine before PTU (substrate for more hormone)
Aspirin for fever (displaces T4 from TBG)
Not giving steroids (relative adrenal insufficiency)
Missing the precipitant (infection, surgery, non-adherence)
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
EMERGENTEndocrinology
Adrenal Crisis
Acute cortisol deficiency → refractory hypotension, shock, and death if untreated. Most commonly from abrupt steroid withdrawal or physiologic stress in a patient with adrenal suppression. Give hydrocortisone first, diagnose later.
🔍 Overview
Common Causes
Category
Examples
#1 -Steroid withdrawal
Abrupt discontinuation of chronic steroids (≥ 3 weeks of prednisone ≥ 20 mg/day suppresses HPA axis). Patient gets sick, can't take oral meds, and crashes. Always taper steroids.
Primary adrenal insufficiency (Addison)
Autoimmune adrenalitis (#1 in developed world), TB (#1 worldwide), adrenal hemorrhage (Waterhouse-Friderichsen -meningococcemia), metastatic disease, drugs (ketoconazole, etomidate)
Secondary (pituitary)
Pituitary tumor/surgery/apoplexy, chronic steroid use suppressing ACTH, checkpoint inhibitor hypophysitis
Critical illness-related
Relative adrenal insufficiency in septic shock (adrenals cannot mount adequate cortisol response to stress)
Clinical Features
Hypotension refractory to fluids and vasopressors -the hallmark. Cortisol is required for vascular tone and catecholamine sensitivity.
Hyponatremia + hyperkalemia (primary AI -aldosterone deficiency). Secondary AI → hyponatremia only (aldosterone preserved).
Hypoglycemia -cortisol is needed for gluconeogenesis
Hyperpigmentation -primary AI only (↑ ACTH → ↑ MSH from POMC cleavage). Absent in secondary AI.
Think adrenal crisis in any patient with refractory hypotension + hyponatremia + hypoglycemia + eosinophilia -especially if on chronic steroids or has a history of autoimmune disease.
Diagnosis
Random cortisol: AM cortisol < 3 mcg/dL is diagnostic of AI. > 15–18 rules it out. Between 3–15 = indeterminate → cosyntropin stim test.
Cosyntropin (ACTH) stimulation test: Give 250 mcg cosyntropin IV/IM → check cortisol at 30 and 60 min. Cortisol < 18 mcg/dL = adrenal insufficiency.
In crisis: draw cortisol and ACTH, then treat immediately. Do NOT wait for results.
Use dexamethasone, not hydrocortisone, if you still need to run the cosyntropin stim test. Hydrocortisone cross-reacts with the cortisol assay and will invalidate the results. Dexamethasone provides glucocorticoid coverage while you treat the patient but does NOT interfere with the cortisol measurement, so you can give dex, stabilize the patient, and still get an accurate stim test.
🚨 Management
Acute Adrenal Crisis
Immediate
Hydrocortisone 100 mg IV bolus → then 50 mg IV q8h (or 200 mg/24h continuous infusion) Endocrine Society Guidelines, 2016. Do NOT wait for labs. Hydrocortisone at stress doses provides both glucocorticoid AND mineralocorticoid activity.
Volume resuscitation
Aggressive NS boluses -these patients are profoundly volume-depleted. D5NS if hypoglycemic. The hypotension often dramatically improves within 1–2h of hydrocortisone + fluids.
Treat precipitant
Infection is the most common trigger. Broad-spectrum antibiotics if sepsis suspected.
Taper
Once stable → taper hydrocortisone over 3–5 days to physiologic replacement: hydrocortisone 15–20 mg AM + 5–10 mg PM (or prednisone 5 mg AM). Add fludrocortisone 0.1 mg daily if primary AI (mineralocorticoid replacement).
Stress Dose Steroids -When to Give
Stress Level
Dose
Examples
Minor illness
Double daily dose × 2–3 days
Mild URI, dental procedure, minor stress
Moderate illness/surgery
Hydrocortisone 50 mg IV q8h × 1–2 days
Moderate surgery, pneumonia, GI illness with vomiting
Severe stress / major surgery / critical illness
Hydrocortisone 100 mg IV q8h
Major surgery, sepsis, trauma, ICU admission Endocrine Society, 2016
Any patient on chronic steroids (≥ 20 mg prednisone/day × ≥ 3 weeks in the past year) should be assumed to have HPA axis suppression and needs stress-dose steroids during acute illness/surgery. This includes patients who recently tapered off. When in doubt, give hydrocortisone -the risk of one dose is minimal, the risk of missing adrenal crisis is fatal.
📋 Clinical Example -Adrenal Crisis Management
Patient: 55M on chronic prednisone 20mg daily for PMR, admitted for pneumonia. Now day 2, found hypotensive (BP 72/48), lethargic, Na 128, K 5.8, glucose 52.
Recognition: This is adrenal crisis -he is on chronic steroids (HPA axis suppressed) and the pneumonia is a physiologic stress. His daily prednisone dose is insufficient for acute illness.
Immediate treatment (do NOT wait for cortisol levels):
Hydrocortisone (Solu-Cortef) 100mg IV STAT → then 50mg IV q8h. This is life-saving.
NS bolus 1-2L (correct hypotension and hyponatremia). Dextrose for hypoglycemia.
If a cortisol level / cosyntropin stim test is still pending: give dexamethasone (4 mg IV) instead of hydrocortisone for the initial coverage. Dexamethasone does NOT cross-react with the cortisol assay, so it provides glucocorticoid coverage while preserving the diagnostic measurement. Hydrocortisone DOES cross-react and will invalidate the cortisol level. Switch to hydrocortisone after the stim test is drawn.
Stress dose steroid equivalents:
Mild stress (minor procedure): hydrocortisone 50mg IV × 1
Moderate stress (pneumonia, surgery): hydrocortisone 50mg IV q8h × 24-48h
Severe stress (septic shock, major surgery): hydrocortisone 100mg IV q8h
Who needs stress dose steroids? Any patient on ≥ prednisone 5mg/day for ≥3 weeks (or equivalent) in the past year. When in doubt, give stress dose -the risk of NOT giving it (death) far outweighs the risk of giving it (mild hyperglycemia).
Taper: Once stress resolves, taper back to home dose over 1-3 days. Do NOT abruptly stop.
📋 On Rounds
How do you distinguish primary from secondary adrenal insufficiency?
Key differences: (1) ACTH level: ↑ in primary (adrenal glands failing → pituitary cranks up ACTH), ↓ in secondary (pituitary failing → no ACTH signal). (2) Hyperkalemia: present in primary (aldosterone deficiency from destroyed adrenal cortex), absent in secondary (aldosterone is regulated by RAAS, not ACTH, so it's preserved). (3) Hyperpigmentation: present in primary only (high ACTH → cleavage of POMC → MSH)
A surgical patient on chronic prednisone 10 mg daily is going to the OR. What stress dose do you give?
The adrenal gland normally produces ~5–10 mg cortisol/day at baseline and up to 75–100 mg/day during major physiological stress (surgery, sepsis, trauma). A patient on chronic prednisone ≥ 5 mg/day for > 3 weeks has HPA axis suppression and cannot mount this stress response. Stress dosing by surgical severity: Minor (local/dental): take usual dose morning of surgery.
How do you differentiate primary from secondary adrenal insufficiency?
Primary (Addison's): adrenal gland destruction → low cortisol + HIGH ACTH (pituitary trying to stimulate failed adrenals). Hyperpigmentation (ACTH shares a precursor with MSH → melanin production). Mineralocorticoid deficiency → hyperkalemia + hyponatremia. Causes: autoimmune (#1 in developed world), TB (#1 worldwide), bilateral adrenal hemorrhage (Waterhouse-Friderichsen in meningococcemia), metastases.
What is the cosyntropin stimulation test and how do you interpret it?
Cosyntropin (synthetic ACTH) 250 mcg IV or IM → check cortisol at 0, 30, and 60 minutes. Normal response: cortisol rises to ≥ 18 mcg/dL (some labs use ≥ 20) at 30 or 60 min. If cortisol fails to rise to ≥ 18 → adrenal insufficiency confirmed. Interpretation: Low baseline + fails stim = AI. Low baseline + passes stim = may still have secondary AI (pituitary failure) if the adrenals haven't atrophied yet (early secondary AI).
A critically ill patient with refractory hypotension has a random cortisol of 8. Do you treat?
Yes -empirically. In critical illness, cortisol should be > 18-25. A level of 8 in a stressed patient = relative adrenal insufficiency. Give hydrocortisone 100 mg IV and don't wait for ACTH stim test.
Why must you treat cortisol deficiency BEFORE starting levothyroxine?
Levothyroxine increases metabolic rate and cortisol clearance. In a patient with unrecognized adrenal insufficiency, starting thyroid hormone can precipitate adrenal crisis. Always replace cortisol first.
What are the sick-day rules for adrenal insufficiency?
Double oral dose for minor illness, triple for major illness, IV stress-dose (100 mg hydrocortisone) for surgery/trauma/vomiting. All AI patients must carry an emergency injection kit and wear a medical alert bracelet.
Clinical Examples
📋 Case 1, Adrenal Crisis from Steroid Withdrawal
Patient: 62M, COPD on chronic prednisone 15 mg daily x 2 years, ran out of medication 5 days ago. Presents with nausea, vomiting, abdominal pain, and near-syncope.
Key findings: T 99.8°F, HR 112, BP 74/48 (refractory to 3L NS). Na 128, K 5.6, glucose 58, Cr 1.9 (baseline 1.1). Random cortisol 2.1. ACTH pending.
Management:
Hydrocortisone 100 mg IV bolus IMMEDIATELY, do not wait for confirmatory tests
D5NS for volume resuscitation + hypoglycemia correction
Hydrocortisone 50 mg IV q8h after initial bolus
BP improved to 98/62 within 2 hours of steroid administration
Taper to oral prednisone over 3-5 days; endocrine consult for slow taper plan
Teaching point: This is tertiary adrenal insufficiency (chronic exogenous steroids suppressed the HPA axis). Abrupt withdrawal after ≥ 3 weeks of prednisone ≥ 5 mg/day can precipitate crisis. BP improved rapidly because cortisol restores vascular catecholamine sensitivity. Endocrine Society, 2016
📋 Case 2, Perioperative Stress Dosing Failure
Patient: 45F, SLE on prednisone 10 mg daily, undergoes elective total knee replacement. Took her usual morning prednisone but no stress-dose steroids were given. 6 hours post-op: hypotension (BP 72/40), tachycardia (HR 130), unresponsive to 4L crystalloid and norepinephrine.
Key findings: Glucose 52, Na 131, K 5.4. Lactate 4.2. Surgical site hemostasis adequate. Intra-op blood loss 400 mL (EBL). Random cortisol 3.8.
Management:
Hydrocortisone 100 mg IV stat, vasopressor-refractory hypotension in chronic steroid user = adrenal crisis until proven otherwise
Continue hydrocortisone 50 mg IV q8h x 48-72h
Rapid hemodynamic improvement (weaned norepi within 4h)
Taper to home prednisone dose over 3 days as clinical status improves
Teaching point: Major surgery requires stress-dose steroids in any patient on chronic steroids (≥ 5 mg prednisone daily for > 3 weeks). The adrenals normally produce up to 75-100 mg cortisol/day under surgical stress. The usual 10 mg prednisone is equivalent to only ~12.5 mg hydrocortisone, far below perioperative needs.
📋 Case 3, Primary Adrenal Insufficiency (Addison's) with Sepsis
Patient: 38F, known Addison disease on hydrocortisone 20 mg AM / 10 mg PM + fludrocortisone 0.1 mg daily, presents with 2 days of fever, cough, and inability to keep medications down due to vomiting.
Key findings: T 102.4°F, HR 128, BP 68/38. Hyperpigmented skin creases and buccal mucosa. Na 126, K 6.2, glucose 48. CXR: RLL consolidation. Lactate 5.8.
Management:
Hydrocortisone 100 mg IV bolus, then 50 mg IV q6h (crisis-dose)
D5NS aggressive resuscitation; dextrose for hypoglycemia
No additional fludrocortisone needed at stress doses (hydrocortisone > 50 mg/day has adequate mineralocorticoid activity)
Ceftriaxone + azithromycin for CAP (the trigger)
Emergent K management: calcium gluconate, insulin + D50, kayexalate
Teaching point: All patients with known adrenal insufficiency must have sick-day rules: double oral dose for minor illness, triple for major illness, IM/IV stress dose if vomiting. This patient could not absorb oral meds. The hyperkalemia is from mineralocorticoid deficiency (primary AI destroys the entire adrenal cortex including zona glomerulosa).
📣 Sample Presentation
One-Liner
"Mr. Owens is a 58-year-old on chronic prednisone 15 mg daily for COPD who ran out of medication 5 days ago and presents with hypotension (BP 74/48 refractory to 3L IVF), nausea, and confusion. Na⁺ 128, K⁺ 5.6. Adrenal crisis."
Key Points to Cover on Rounds
Adrenal crisis -tertiary adrenal insufficiency (chronic exogenous steroid → HPA axis suppression → abrupt withdrawal). Treatment: hydrocortisone 100 mg IV bolus immediately, then 50 mg IV q8h. IVF resuscitation with D5NS (hypoglycemia risk). Na 128 will correct with cortisol replacement (cortisol is needed for free water excretion). K⁺ 5.6 will correct with cortisol (mineralocorticoid effect). Cortisol and ACTH were drawn before hydrocortisone (but didn't delay treatment). BP improved to 98/62 within 2 hours. Plan: taper to oral prednisone over 3-5 days, endocrine to develop slow steroid taper schedule, medic alert bracelet.
🧪 Workup
Workup
AM cortisol -draw before giving steroids if possible. < 3 mcg/dL = adrenal insufficiency confirmed. > 18 = AI excluded. 3-18 = need ACTH stim test.
ACTH stimulation test (cosyntropin) -250 mcg IV → cortisol at 0 and 60 min. Normal = cortisol ≥ 18 at 60 min. Do NOT delay steroids for this test -give dexamethasone (does not interfere with cortisol assay) while awaiting results.
21-hydroxylase antibodies -autoimmune adrenalitis (most common cause in developed countries)
💊 Medications
Medications
Drug
Dose
Route
Notes
Hydrocortisone
Endocrine Society, 2016 100 mg IV bolus → 50 mg IV q8h
IV
First-line for adrenal crisis. Has both glucocorticoid AND mineralocorticoid activity. Taper as patient improves.
Dexamethasone
Endocrine Society, 2016 4 mg IV q12h
IV
Alternative if ACTH stim test pending -does not interfere with cortisol assay. No mineralocorticoid activity -add fludrocortisone.
NS (normal saline)
1-2L bolus, then maintenance
IV
Aggressive volume resuscitation. These patients are volume-depleted from mineralocorticoid deficiency. Add D5 if hypoglycemic.
Fludrocortisone (Florinef)
Endocrine Society, 2016 0.05-0.2 mg daily
PO
Mineralocorticoid replacement for primary AI (Addison's). Not needed in secondary AI (ACTH deficiency preserves aldosterone). Start once PO tolerating.
Hydrocortisone (maintenance)
15-25 mg daily (10 AM + 5 PM)
PO
Chronic replacement. Mimic diurnal pattern. Sick-day rules: double or triple dose during illness/surgery.
Sick-day rules: All AI patients must carry an emergency injection kit (100 mg hydrocortisone IM) and wear a medical alert bracelet. Double oral dose for minor illness, triple for major illness, IV stress-dose for surgery/trauma.
⚡ Summary
Summary
Give Hydrocortisone First, Diagnose Later
Hydrocortisone 100 mg IV immediately, then 50 mg q6h or a continuous infusion, plus aggressive isotonic fluid resuscitation.Adrenal crisis kills through refractory hypotension, and the delay to confirm the diagnosis is the delay that kills. Draw a cortisol and ACTH first if it takes seconds, but never wait for the result.
Recognize the Lab Signature
Refractory hypotension with hyponatremia, hyperkalemia, hypoglycemia and eosinophilia, especially in a patient on chronic steroids or with autoimmune disease. Hypotension that does not respond to fluids and vasopressors is the clinical hallmark, and the shock becomes responsive within hours of steroid replacement.
Use Dexamethasone if You Still Need the Stim Test
Hydrocortisone cross-reacts with the cortisol assay and invalidates the cosyntropin stimulation test.Dexamethasone provides glucocorticoid cover without interfering, so it is the right choice when the diagnosis is genuinely unclear and the test will be run. Do not let this delay treatment either.
Assume HPA Suppression Liberally
Any patient on 20 mg of prednisone daily or more for 3 weeks or longer within the past year should be assumed to have a suppressed axis, including those who recently stopped. Recovery takes months to a year. The commonest cause of adrenal crisis is abrupt withdrawal of exogenous steroid, not Addison disease.
Match the Stress Dose to the Stress
Minor illness or minor procedure: double or triple the usual dose for 2 to 3 days.Moderate surgery: hydrocortisone 50 mg IV before and q8h for 24 h.Major surgery, trauma or critical illness: 100 mg IV then 50 mg q6h, tapering over days.Over-covering for a few days is harmless; under-covering can be fatal.
Separate Primary From Secondary
Primary (adrenal): high ACTH, hyperpigmentation, mineralocorticoid deficiency with hyperkalemia, and it needs fludrocortisone in addition to hydrocortisone.Secondary (pituitary or exogenous): low ACTH, no hyperpigmentation, aldosterone intact, so no fludrocortisone needed.Fludrocortisone is unnecessary while on high-dose hydrocortisone, which has enough mineralocorticoid activity of its own.
Correct the Sodium With Steroid and Saline, Not With Restriction
The hyponatremia is driven by cortisol deficiency causing inappropriate ADH release plus, in primary disease, aldosterone deficiency.It corrects with hydrocortisone and isotonic fluid, and it can correct fast, so watch the rate to avoid overcorrection and osmotic demyelination.
Prevent the Next Crisis Before Discharge
Every patient needs a medical alert bracelet, an emergency hydrocortisone injection kit with training for them and a family member, and written sick-day rules.Check thyroid function too: in autoimmune polyglandular disease, treating hypothyroidism before adrenal insufficiency precipitates crisis, so the steroid always goes first.
RoundsRx Infographic Series · #85 · Toxicology & Emergencies · PDF 148 KB
Text version
Endocrine · One Pager
Adrenal Insufficiency & Crisis
Hydrocortisone 100 mg IV immediately for crisis. Don't wait for labs. Primary = high ACTH + hyperpigmentation + hyperK. Secondary = low ACTH. Stress dosing rules for all patients.
🧪 Classification
Primary (Addison): adrenal destruction → low cortisol + HIGH ACTH + hyperpigmentation + hyperkalemia. Secondary/tertiary: pituitary/hypothalamic failure or chronic steroids → low cortisol + LOW ACTH. No hyperpigmentation, no hyperK.
🚨 Crisis Treatment
Hydrocortisone 100 mg IV bolus immediately → 50 mg q8h. IVF with D5NS (hypoglycemia risk). Don't wait for cosyntropin test results. Draw cortisol + ACTH before treatment if possible (don't delay).
💊 Chronic Management
Hydrocortisone 15-25 mg/day (divided: 2/3 AM + 1/3 PM). Fludrocortisone 0.05-0.1 mg daily (primary only -mineralocorticoid). Stress dosing: double dose for illness, 100 mg IV for surgery. Medic alert bracelet.
💊 Key Drugs
Hydrocortisone (Solu-Cortef)100 mg IV bolus (crisis)
Hydrocortisone (Solu-Cortef)15-25 mg/day PO (chronic)
Fludrocortisone0.05-0.1 mg daily (primary)
DexamethasoneIf testing needed (doesn't interfere with assay)
⚠️ Pitfalls
Waiting for cosyntropin results to treat crisis (treat immediately)
Forgetting fludrocortisone in primary AI (needed for mineralocorticoid)
Abrupt steroid withdrawal → crisis
Not teaching stress dosing rules and emergency injection
Related Topics
Cushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' DiseaseHypocalcemia
EndocrinologyCommon
SIADH
Too much ADH, so water is retained and the sodium falls while the patient stays euvolemic. The whole diagnosis rests on paired osmolalities plus a volume assessment, and the whole danger is correcting too fast. Includes side-by-side comparisons with diabetes insipidus (the mirror image) and cerebral salt wasting (the look-alike with the opposite treatment).
💧 Overview
Diagnostic Criteria, ALL Must Be Present
Serum Na⁺ < 135 mEq/L (hyponatremia)
Serum osmolality < 275 mOsm/kg (truly hypo-osmolar, which excludes pseudohyponatremia and hyperglycemia)
Urine osmolality > 100 mOsm/kg (inappropriately concentrated: in a hypo-osmolar state the kidney should be making maximally dilute urine)
Urine sodium > 40 mEq/L on a normal salt intake (the kidney is not volume-depleted, so it is not avidly retaining sodium)
Clinically euvolemic (no edema, no orthostasis, no JVD)
Normal thyroid and adrenal function, and no recent diuretic
SIADH is a diagnosis of exclusion. Check TSH and an AM cortisol before you commit to it. Hypothyroidism and adrenal insufficiency both produce euvolemic hyponatremia with concentrated urine, both are treatable with specific therapy, and both are missed if you anchor on SIADH early. Thiazides are the other great mimic: they cause hyponatremia with a high urine sodium and can look identical.
Why the Sodium Falls
SIADH is a water problem, not a salt problem. ADH acts on V2 receptors in the collecting duct, inserting aquaporin-2 channels and retaining free water. The retained water dilutes the sodium. Volume expansion is only transient, because the kidney escapes by excreting sodium (pressure natriuresis plus natriuretic peptides), which is why the patient ends up euvolemic with a high urine sodium rather than edematous. That is also why giving isotonic saline can make things worse: if urine osmolality exceeds the osmolality of the fluid you infuse, the kidney excretes the salt and keeps the water. This is the desalination phenomenon.
Causes, Grouped the Way You Should Search for Them
Category
Specifics
Clinical clue
Drugs the first thing to review
SSRIs (most common drug cause), carbamazepine and oxcarbazepine, cyclophosphamide, vincristine, NSAIDs, antipsychotics, MDMA, desmopressin, thiazides (a mimic rather than true SIADH)
Onset typically 2 to 4 weeks after starting the drug, and the elderly are most at risk. Check a sodium at that interval after starting an SSRI.
CNS disease
Stroke, subarachnoid hemorrhage, head trauma, meningitis, encephalitis, brain tumor, and post-neurosurgical states
In a hyponatremic SAH patient you must separate SIADH from cerebral salt wasting before restricting fluids. See the comparison tab.
Pulmonary disease
Pneumonia, tuberculosis, lung abscess, empyema, and positive-pressure ventilation
Often resolves as the lung process resolves; no specific therapy is needed beyond treating the pneumonia.
Malignancy
Small cell lung cancer is the classic ectopic ADH producer, then head and neck cancers
Unexplained SIADH in a smoker warrants chest imaging. Hyponatremia may be the presenting sign of SCLC.
Pain, nausea, post-op
Any severe pain or nausea is a potent physiologic ADH stimulus
Frequently overlooked. Treating the pain and nausea treats the hyponatremia, so do that before reaching for tolvaptan.
🧪 Workup
The Three Tests That Make the Diagnosis
Send a serum osmolality, a urine osmolality and a urine sodium at the same time, before you give any fluid. Paired samples are the entire workup. A urine osmolality drawn after a saline bolus is uninterpretable, and this is the single most common way the diagnosis gets muddied.
Step
Test
How to read it
1. Is it truly hypo-osmolar?
Serum osmolality
< 275 confirms true hyponatremia. If normal or high, you have pseudohyponatremia (severe hyperlipidemia or paraproteinemia) or a second osmole such as glucose, mannitol or ethanol. Correct sodium for glucose before going further.
2. Is ADH acting?
Urine osmolality
> 100 means ADH is on when it should be off. A urine osmolality < 100 points instead to primary polydipsia, beer potomania or low solute intake, where the kidney is diluting appropriately and the problem is intake.
3. What is the volume state?
Urine sodium plus the bedside exam
> 40 with clinical euvolemia supports SIADH. < 20 means an avidly sodium-retaining kidney, so think hypovolemia or a low effective circulating volume state (heart failure, cirrhosis).
Before You Commit to the Diagnosis
TSH and AM cortisol on every patient, because hypothyroidism and adrenal insufficiency mimic SIADH exactly and are treatable
Review the medication list with SSRIs, carbamazepine and thiazides specifically in mind
Serum uric acid is low (< 4 mg/dL). Urate is reabsorbed in the proximal tubule coupled to sodium. SIADH retains water, which mildly expands the effective circulating volume, and that expansion switches off proximal sodium reabsorption. Urate is lost along with it. It does not distinguish SIADH from cerebral salt wasting, where it is also low
BUN is low or low-normal from dilution; a raised BUN should make you reconsider hypovolemia
Chest imaging if the cause is not obvious, particularly in a smoker, to look for small cell lung cancer
Document the acuity. Hyponatremia known to be under 48 hours old can be corrected faster; anything undocumented is treated as chronic, which is the safe assumption
⚡ Management
Treatment by Severity
Scenario
Treatment
Correction target and cautions
Symptomatic (seizure, coma, severe altered mental status)
3% hypertonic saline 100 to 150 mL IV bolus over 10 to 20 min. May repeat up to twice if symptoms persist. ICU admission and frequent sodium checks.
Immediate goal is to raise the sodium by 4 to 6 mEq/L in the first 6 hours, which is enough to stop seizures and reduce cerebral edema. Then hold at ≤ 8 mEq/L total in 24 hours. You are treating the brain, not the number.
Asymptomatic or chronic (Na 120 to 134)
Fluid restriction 800 to 1000 mL/day, stop the offending drug, and treat the underlying cause. Add salt tablets or oral urea 15 to 30 g daily if restriction alone fails.
≤ 8 mEq/L per 24 hours. The brain has adapted by extruding osmolytes, so a fast correction is what injures it. Fluid restriction is slow and often unpopular with patients, so set expectations.
Refractory
Tolvaptan 15 mg PO daily, a V2 receptor antagonist producing a free water aquaresis. SALT-1 and SALT-2, 2006
Start inpatient only and check sodium at 4 to 6 h, 8 to 12 h and 24 h. Do not combine with hypertonic saline or fluid restriction during initiation, since the combination overcorrects. Hepatotoxicity limits use to 30 days.
Predicting who will fail fluid restriction. Restriction is unlikely to work if the urine osmolality is above 500, or if the urine sodium plus urine potassium exceeds the serum sodium (the patient is generating negative free water clearance and would need an impractically tight restriction). Those patients need salt plus a loop diuretic, urea, or tolvaptan rather than a doomed trial of restriction.
Verbalis Expert Panel, 2013Osmotic demyelination syndrome. Correcting faster than 8 mEq/L in 24 hours destroys myelin in the central pons, producing dysarthria, dysphagia, quadriparesis and a locked-in syndrome. It appears 2 to 6 days later and is irreversible. Highest risk: chronic hyponatremia, Na < 105, alcohol use disorder, malnutrition, hypokalemia and liver disease, where the ceiling drops to 6 mEq/L per 24 h. If you are overcorrecting, act immediately: D5W plus DDAVP 2 mcg IV q8h to re-lower the sodium onto a safe trajectory.
⚖️ SIADH vs DI & CSW
SIADH vs Diabetes Insipidus, the Mirror Image
Same hormone, opposite ends. SIADH is too much ADH so water is retained and the sodium falls. DI is too little ADH, or a kidney that cannot respond to it, so free water is lost and the sodium rises. Both are diagnosed with paired serum and urine osmolalities.
Feature
SIADH
Diabetes Insipidus
ADH
Excess (or ectopic)
Deficient (central) or ineffective (nephrogenic)
Serum sodium
Low, often 120s
High, if the patient cannot reach water
Serum osmolality
< 275
> 290
Urine osmolality
> 100, inappropriately concentrated
< 300, inappropriately dilute
Urine output
Normal or low
Polyuria > 3 L/day
Volume status
Euvolemic
Euvolemic to hypovolemic
Treatment
Restrict water. Salt, urea or tolvaptan if refractory
Give water. DDAVP for central; remove the cause plus thiazide for nephrogenic
They can occur in the same patient, in sequence. After pituitary surgery about a quarter of patients show the triphasic response: DI for a few days, then a SIADH phase around days 5 to 10 as stored ADH is released from the dying posterior pituitary, then permanent DI. Continuing DDAVP into the SIADH phase causes fatal hyponatremia, so when the urine output falls and the sodium starts dropping, stop the DDAVP.
SIADH vs Cerebral Salt Wasting, the Dangerous Look-Alike
The labs are nearly identical and the treatments are opposite. Both give hyponatremia, urine osmolality above 100, urine sodium above 40, and a low uric acid, usually in a patient with intracranial pathology. Volume status is the discriminator. Fluid-restricting a cerebral salt wasting patient with subarachnoid hemorrhage worsens volume depletion and drives delayed cerebral ischemia and vasospasm.
Feature
SIADH
Cerebral salt wasting
Primary defect
ADH excess, so water is retained
Renal sodium wasting, so water follows the salt out
Low. Does not distinguish them, which is the classic trap
Fractional excretion of urate
Elevated in both while hyponatremic, so it is useless on first encounter. After the sodium is corrected it normalizes to < 11% in SIADH but stays > 11% in cerebral salt wasting, which is the most reliable discriminator described.
Response to saline
No change, or the sodium falls further through desalination
Improves
Treatment
Fluid restriction
Isotonic saline and salt repletion.Fludrocortisone 0.1 to 0.2 mg daily reduces the natriuresis. Never fluid restrict.
Practical approach at the bedside: assess volume properly with strict intake and output, daily weights, orthostatics and a CVP if a line is already in, then consider a trial of isotonic saline, since cerebral salt wasting improves and SIADH does not. Note that the existence of cerebral salt wasting is contested, with many arguing most labeled cases are really SIADH, but in the neurosurgical population the distinction still changes what you do.
💊 Medications
Key Medications in SIADH
Drug
Dose
Role
Watch for
Hypertonic saline 3%
100 to 150 mL IV bolus over 10 to 20 min, repeat up to twice
Symptomatic hyponatremia only (seizure, coma, severe altered mental status)
Aim for a 4 to 6 mEq/L rise in 6 h, then stop. Recheck sodium 2 h after each bolus. Peripheral administration of small boluses is acceptable.
Sodium chloride tablets
1 g PO TID, titrated
Add-on when fluid restriction alone is not enough
Often paired with a loop diuretic when urine osmolality is high, since the loop lowers urinary concentrating ability.
Urea (oral)
15 to 30 g daily
Induces an osmotic diuresis of free water; useful for chronic SIADH
Poor palatability is the main limit. Cheaper than tolvaptan and no hepatotoxicity ceiling.
Tolvaptan (Samsca)
15 mg PO daily, titrate to 30 to 60 mg
V2 receptor antagonist producing free water aquaresis without sodium loss
Inpatient initiation only. Sodium at 4 to 6 h, 8 to 12 h and 24 h. Do not combine with hypertonic saline or fluid restriction at initiation. Hepatotoxicity limits use to 30 days.
Desmopressin (DDAVP)
2 mcg IV q8h for rescue; 1 to 2 mcg IV/SC q12h for central DI
Two opposite roles: ODS rescue in overcorrected hyponatremia, and replacement in central DI
In rescue, pair with D5W to re-lower the sodium. Know which indication you are treating before you order it.
Fludrocortisone
0.1 to 0.2 mg PO daily
Cerebral salt wasting, to reduce renal sodium wasting
Watch for volume overload, hypokalemia and hypertension. Not a treatment for SIADH.
The commonest medication error here is treating the number instead of the patient. A sodium of 118 that is chronic and asymptomatic needs fluid restriction and patience. A sodium of 124 with a seizure needs hypertonic saline now. Symptoms, not the absolute value, decide how aggressive you are.
📋 On Rounds
A patient's Na corrected from 112 to 124 in 18 hours. What do you do?
That's a 12 mEq/L correction in 18h, too fast. The safe limit is ≤ 8 mEq/L in 24h. Immediate steps: (1) D5W infusion (free water to re-lower Na), (2) DDAVP 2 mcg IV q8h (replaces ADH so the kidneys retain free water and Na drops back), (3) target Na no more than 8 mEq/L above the starting value for the 24h period. The goal is to "re-lower" the sodium onto a safe correction trajectory.
Hyponatremia in a patient 5 days after subarachnoid hemorrhage. Why is fluid restriction the wrong reflex?
Because it may be cerebral salt wasting, not SIADH. The labs look identical (low Na, urine osm > 100, urine Na > 40, low uric acid) but CSW patients are hypovolemic. Restricting fluid deepens the volume depletion and increases delayed cerebral ischemia and vasospasm. Assess volume status, and if uncertain give isotonic saline: CSW improves, SIADH does not.
Why do thiazides paradoxically help nephrogenic DI?
Counterintuitive but elegant: thiazides block NaCl reabsorption in the distal convoluted tubule causing mild sodium and volume depletion, so the body compensates by increasing proximal tubule reabsorption of sodium and water. Less water reaches the ADH-insensitive collecting duct, so less dilute urine is produced and urine volume falls, by roughly 30 to 50%.
How does tolvaptan work and why must you start it inpatient?
Tolvaptan is a V2 receptor antagonist that blocks ADH at the collecting duct, inducing a free water diuresis (aquaresis) without sodium loss, so the urine concentrates and the plasma dilutes and sodium rises. It must be started inpatient because the correction can be rapid and unpredictable, risking overcorrection and osmotic demyelination. Check sodium at 4 to 6h, 8 to 12h and 24h after the first dose.
What are the criteria for diagnosing SIADH?
All must be met: (1) serum osm < 275 (hypo-osmolar), (2) urine osm > 100 (inappropriately concentrated, since the kidney should be making dilute urine in a hypo-osmolar state), (3) euvolemic (no edema, no JVD, no orthostasis), (4) urine Na > 40, (5) normal thyroid and adrenal function with no recent diuretic.
A patient with Na 118 and seizures. What do you give and how fast do you correct?
3% hypertonic saline 100 to 150 mL bolus over 10 to 20 min, repeatable up to twice. Target a 4 to 6 mEq/L rise in the first 6h to stop the seizure. Do not exceed 8 mEq/24h (6 if high-risk). Overcorrection causes osmotic demyelination syndrome.
What is the most dangerous time for osmotic demyelination syndrome?
ODS presents 2 to 6 days after overcorrection with dysarthria, dysphagia, quadriparesis and locked-in syndrome. Risk factors: chronic hyponatremia over 48h, alcohol use disorder, malnutrition, liver disease and hypokalemia.
Why must you check TSH and cortisol before diagnosing SIADH?
Both hypothyroidism and adrenal insufficiency cause hyponatremia and mimic SIADH exactly (euvolemic, concentrated urine). Both are treatable with specific therapy and both are missed if you anchor early. SIADH is a diagnosis of exclusion.
Clinical Examples
📋 Case 1, SSRI-Induced SIADH
Patient: 72-year-old woman started on escitalopram 3 weeks ago for depression. Presents with fatigue, nausea, mild confusion. Na 118, serum osm 248, urine osm 520, UNa 58. Euvolemic. TSH and AM cortisol normal.
Key findings: Classic SSRI-induced SIADH. All diagnostic criteria met: hypo-osmolar, inappropriately concentrated urine, euvolemic, UNa > 40, normal thyroid and adrenal function.
Management:
Hold escitalopram (offending agent)
Fluid restriction < 1 L/day
Na q4-6h (symptomatic with confusion)
If Na not improving: salt tabs 1g TID
Correction rate ≤ 8 mEq/L per 24h (high risk: elderly)
Teaching point: SSRIs are the most common drug cause of SIADH. Always check a sodium 2 to 4 weeks after starting an SSRI in an elderly patient. Leth-Moller et al., 2016
📋 Case 2, Post-Neurosurgical Central DI
Patient: 38-year-old man, POD 1 from transsphenoidal pituitary adenoma resection. UOP 650 mL/hr x 4 hours. Clear, dilute urine. Na 151 (was 140 pre-op), serum osm 308, urine osm 78.
Key findings: Post-surgical central DI. Massive polyuria with inappropriately dilute urine and a rising sodium. Watch for the triphasic response.
Management:
DDAVP 1 mcg IV q12h
D5W to replace the free water deficit and match ongoing losses
Na q4h, strict I&Os, hourly UOP
If UOP drops and Na falls on days 5-10: STOP DDAVP immediately (SIADH phase)
Teaching point: The triphasic response (DI, then SIADH, then permanent DI) occurs in roughly 25% of pituitary surgery patients. Continuing DDAVP into the SIADH phase causes fatal hyponatremia.
📋 Case 3, Overcorrection Rescue
Patient: 65-year-old man with chronic hyponatremia (Na 108) from SCLC-associated SIADH. After 18 hours of 3% saline and fluid restriction, Na corrected to 122, a 14 mEq/L rise.
Key findings: Overcorrection. 14 mEq/L in 18h exceeds the safe limit of 8 mEq/L per 24h. High risk for ODS: chronic, severe hyponatremia and malignancy.
Management:
STOP hypertonic saline immediately
DDAVP 2 mcg IV q8h to re-lower Na
D5W infusion to bring Na back down
Target: Na no more than 8 mEq/L above the starting value for the 24h period (goal Na ≤ 116)
Na q2h until trending downward
Teaching point: ODS rescue (DDAVP plus D5W) should start the moment overcorrection is detected. ODS presents 2 to 6 days later and is irreversible. Verbalis Expert Panel, 2013
📣 Sample Presentation
One-Liner
"Mr. Foster is a 68-year-old started on sertraline 3 weeks ago presenting with Na⁺ 122, serum osm 258, urine osm 480, UNa 52, euvolemic. TSH and cortisol normal. SIADH from SSRI."
Key Points to Cover on Rounds
SIADH, euvolemic hypo-osmolar hyponatremia with inappropriately concentrated urine and a high urine sodium. Cause: sertraline, since SSRIs are the most common drug cause. Asymptomatic, no seizure or altered mental status. Treatment: fluid restriction under 1 L/day started, sertraline held, alternative antidepressant to be discussed with psychiatry. Na trending 122 to 124 to 126 over 36h, a rate of 3 mEq/24h which is safe against a ceiling of 8. Plan: if refractory to restriction, salt tabs 1g TID; if still refractory, tolvaptan inpatient with Na checks at 4 to 6h, 8 to 12h and 24h. ODS rescue protocol available if overcorrected (D5W plus DDAVP).
Monitoring in SIADH
Parameter
Frequency
Target / Action
Serum sodium
q2h while on hypertonic saline, q4-6h if symptomatic, q12-24h once stable
Ceiling ≤ 8 mEq/L per 24 h, or ≤ 6 if high-risk for ODS. The single most important number on this page.
Urine output and fluid balance
Strict, hourly if on hypertonic saline
A sudden water diuresis means the ADH stimulus has switched off and the sodium is about to rise fast. Anticipate overcorrection and consider pre-emptive DDAVP.
Urine osmolality
At diagnosis, then if not responding
Above 500 predicts failure of fluid restriction. Falling values mean ADH is switching off.
Potassium
Daily
Hypokalemia raises ODS risk, and repleting it also raises the sodium, so count it in your 24h correction budget.
Neurologic exam
Each assessment
Improving mental status guides how aggressive to be. New dysarthria, dysphagia or weakness 2 to 6 days after correction suggests ODS.
⚡ Summary
Summary
The Diagnosis Rests on Paired Osmolalities Plus Volume
Hypotonic hyponatremia with a low serum osmolality, inappropriately concentrated urine (osmolality above 100), a urine sodium above 30 to 40 on a normal salt intake, and clinical euvolemia, with normal thyroid and adrenal function and no diuretics. All of these must be present: SIADH is a diagnosis of exclusion, not a label for any hyponatremia.
Assess Volume Status First
Hypovolemic hyponatremia and SIADH have overlapping labs and completely opposite treatments.Giving saline to true SIADH can lower the sodium further, because the salt is excreted while the water is retained. A cautious saline challenge helps: hypovolemia improves, SIADH does not or worsens.
Search the Causes in Four Groups
CNS disease (stroke, hemorrhage, infection, trauma), pulmonary disease (pneumonia, tuberculosis, positive pressure ventilation), malignancy (small cell lung cancer above all), and drugs (SSRIs, carbamazepine, cyclophosphamide, antipsychotics, NSAIDs, MDMA). Pain, nausea and the postoperative state are potent and reversible stimuli that are frequently overlooked.
Uric Acid Points Toward It
Serum uric acid is low, below about 4 mg/dL. Urate is reabsorbed in the proximal tubule coupled to sodium; the mild volume expansion of SIADH switches off proximal sodium reabsorption and urate is lost with it. It does not distinguish SIADH from cerebral salt wasting, where it is also low.
Correct Slowly: 8 mEq/L in 24 Hours
Do not exceed 8 mEq/L in 24 h, or 6 in high-risk patients (alcohol use disorder, malnutrition, hypokalemia, advanced liver disease, chronic hyponatremia). Overcorrection causes osmotic demyelination syndrome, which is devastating and irreversible.Check sodium every 2 to 4 h during active correction, and be prepared to relower with D5W and desmopressin if you overshoot.
Severe Symptoms Override the Slow Rule
Seizures, coma or severe confusion mean 3% hypertonic saline, 100 to 150 mL boluses, aiming for a rapid 4 to 6 mEq/L rise to stop the symptoms.Then stop and revert to the slow limit: the initial bolus buys brain safety, it is not the start of a fast correction.
Match the Chronic Treatment to Severity
Fluid restriction first line for mild to moderate disease, though it works poorly when the urine osmolality is very high. Salt tablets with a loop diuretic, or urea, for inadequate response.Tolvaptan for refractory cases, in hospital with close monitoring, since it causes rapid free water diuresis and overcorrection. Above all, treat the cause, which is what actually resolves it.
Know the Two Look-Alikes
Cerebral salt wasting is hypovolemic, with a high urine output and a genuine negative sodium balance, and it is treated with salt and volume, the opposite of fluid restriction; volume status is the discriminator. Diabetes insipidus is the mirror image: too little ADH or resistance to it, with a high sodium, high output and dilute urine, treated with desmopressin or by removing the renal cause.
"Stones, bones, groans, thrones, and psychiatric overtones." Corrected Ca > 10.5 mg/dL. 90% caused by primary hyperparathyroidism or malignancy. Aggressive IVF is the first treatment for everything -then target the cause.
🔍 Overview
Severity
Level
Corrected Ca
Symptoms
Mild
10.5–12 mg/dL
Often asymptomatic. Fatigue, constipation.
Moderate
12–14 mg/dL
Polyuria, polydipsia, nausea, constipation, confusion, short QT on ECG.
First lab after finding hypercalcemia: PTH. PTH high or normal → primary hyperparathyroidism. PTH low → malignancy or other cause → check PTHrP, vitamin D levels (25-OH and 1,25-OH), SPEP/UPEP.
🥛 Milk-Alkali Syndrome
Classic triad: hypercalcemia + metabolic alkalosis + AKI from excess calcium-containing alkali ingestion. Third most common cause of hypercalcemia in hospitalized patients (after malignancy and primary hyperparathyroidism), and easy to miss because patients describe their calcium carbonate as "antacids" or "Tums" rather than calcium.
Modern setup
Elderly woman taking calcium carbonate (Tums, OsCal, Caltrate) for osteoporosis or GERD, often > 5 g/day elemental calcium. Co-factors that tip her over: thiazide (reduces Ca excretion), volume depletion (NSAIDs, loop diuretics, GI loss), CKD, vitamin D supplementation. Modern incidence rose with widespread OTC calcium use; the historical 1920s "milk + bicarbonate for peptic ulcers" recipe is mostly extinct.
Mechanism (vicious cycle)
High oral Ca and alkali load → mild hypercalcemia + alkalosis.
Hypercalcemia causes renal vasoconstriction and nephrogenic DI → volume depletion → AKI.
AKI prevents the kidney from excreting the alkali load → alkalosis worsens.
Alkalosis further reduces urinary Ca excretion → hypercalcemia worsens.
Loop continues until the calcium source is removed.
Distinguishing labs (PTH suppressed)
Lab
Milk-alkali
vs Primary HPT
vs Malignancy
PTH
Low (suppressed by hyperCa)
High or inappropriately normal
Low (suppressed)
PTHrP
Normal
Normal
Often high (humoral hyperCa of malignancy)
Phosphate
Normal to high
Low (PTH wastes PO4)
Variable
HCO3-
Elevated (metabolic alkalosis)
Normal or mildly low (hyperchloremic acidosis)
Normal
Creatinine
Elevated (AKI is part of the triad)
Often normal
Variable
25-OH / 1,25-OH vit D
Normal (unless coingested)
Variable
1,25 elevated in lymphoma and granulomatous disease
Treatment
Stop the calcium and alkali source immediately. Most cases resolve in 2–7 days.
IV NS 200–500 mL/hr to restore volume and enhance Ca excretion.
Avoid bisphosphonates in most cases. Bone turnover is already suppressed (no osteoclast-driven hyperCa to block), and there is real risk of rebound hypocalcemia once renal Ca handling recovers. Reserve for severe or refractory hypercalcemia.
Hold thiazides (reduce Ca excretion) and any vitamin D supplements.
Dialysis only if severe AKI with refractory hypercalcemia.
Counsel patient and family on safe calcium dosing (target < 1500 mg/day elemental Ca, with food, and separated from PPI).
Boards bait: Elderly woman, calcium carbonate for osteoporosis or "indigestion," now with confusion and AKI. PTH suppressed, phosphate normal-to-high, HCO3- elevated. Don't reach for bisphosphonates. Stop the Tums.
🚨 Management
Acute Hypercalcemia Treatment
Step
Drug
Dose
Onset
Notes
1. Volume
IV NS FIRST
200–500 mL/hr (aggressive -these patients are volume-depleted from hypercalcemia-induced nephrogenic DI)
Hours
Always start here. Volume expansion enhances renal Ca excretion. Target UOP 200–300 mL/hr. Most patients need 3–6 L in first 24h.
2. Calcitonin
Calcitonin (Miacalcin)
4 IU/kg SC/IM q12h
4–6 hours
Fastest onset. Inhibits osteoclasts + enhances renal Ca excretion. Effect is modest (↓ Ca by 1–2 mg/dL) and tachyphylaxis within 48h (receptors downregulate). Bridge to bisphosphonate.
3. Bisphosphonate
Zoledronic acid (Zometa) MOST EFFECTIVE
4 mg IV over 15 min
2–4 days
Potent osteoclast inhibitor. Best for malignancy-associated hypercalcemia. Effect lasts 2–4 weeks. Nephrotoxic -hold if Cr > 4.5. Alternative: pamidronate 60–90 mg IV over 2–4h.
4. Denosumab
Denosumab (Xgeva)
120 mg SC
4–10 days
RANKL inhibitor. Use if bisphosphonate-refractory or CKD (not renally cleared). Risk: severe rebound hypercalcemia when stopped.
Steroids
Hydrocortisone (Solu-Cortef) 200 mg IV/day
As needed
Days
Specific indications: granulomatous disease (sarcoid → steroids ↓ calcitriol production), lymphoma, vitamin D intoxication, myeloma. Ineffective for PTH-mediated or most solid tumor hypercalcemia.
Dialysis
Hemodialysis with low-Ca bath
Emergent
Immediate
Last resort for severe (> 18 mg/dL), symptomatic, refractory, or with AKI preventing bisphosphonate use.
Furosemide for hypercalcemia is largely obsolete. Old teaching was "saline + Lasix." Current evidence: loop diuretics only help if the patient is volume-overlo
🧪 Workup
Workup
PTH -the single most important test. Elevated/inappropriately normal = PTH-mediated (primary hyperparathyroidism 90%). Suppressed = PTH-independent (malignancy, granulomatous, vitamin D).
PTHrP -if PTH suppressed. Humoral hypercalcemia of malignancy (squamous cell lung, renal, breast). Elevated in ~80% of malignancy-associated hypercalcemia.
25-OH vitamin D -exogenous vitamin D toxicity
1,25-dihydroxy vitamin D -elevated in granulomatous disease (sarcoidosis, TB, histoplasmosis, lymphoma) -macrophage 1α-hydroxylase activity. Normal PTH, suppressed PTHrP.
SPEP/UPEP + free light chains -multiple myeloma (osteolytic lesions → calcium release). Must check in unexplained hypercalcemia, especially with bone pain + anemia + renal failure.
Corrected calcium = measured Ca + 0.8 × (4 − albumin). Or use ionized calcium (more accurate, not affected by albumin).
Cr + BUN -hypercalcemia causes nephrogenic DI → dehydration → prerenal AKI (most patients are significantly volume-depleted)
Phosphorus -low in hyperPTH (PTH causes phosphaturia). High in vitamin D toxicity, granulomatous disease, tumor lysis.
💊 Medications
Medications
Drug
Dose
Route
Notes
Normal saline
200-300 mL/hr
IV
FIRST and most important step. Most patients 3-6L depleted from hypercalcemia-induced nephrogenic DI. Restores GFR → renal calcium excretion.
Calcitonin
Endocrine Society, 2014 4 IU/kg IM/SQ q12h
IM/SQ
Fast onset (4-6h). Bridges to bisphosphonate effect. Modest drop (~1-2 mg/dL). Tachyphylaxis at 48h -stop after 2 days.
Zoledronic acid
Zoledronic Acid Hypercalcemia Trial, 2001 4 mg IV over 15 min
IV
Most potent long-term treatment. Onset 2-4 days, peak 4-7 days, lasts weeks. Avoid if CrCl < 35 (use denosumab instead). Monitor for osteonecrosis of jaw (rare).
Denosumab
Denosumab Hypercalcemia Trial, 2014 120 mg SQ
SQ
RANKL inhibitor. Use if renal impairment (not renally cleared) or bisphosphonate failure. Risk of severe rebound hypercalcemia if stopped.
Prednisone
20-40 mg daily
PO
Granulomatous disease and lymphoma ONLY. Blocks 1α-hydroxylase in macrophages. NOT effective for PTH-mediated or PTHrP-mediated.
Cinacalcet
30 mg BID
PO
Calcimimetic for primary hyperPTH (if not surgical candidate). Also parathyroid carcinoma. Lowers PTH → lowers Ca.
Furosemide (Lasix)
20-40 mg IV PRN
IV
ONLY after adequate hydration. Calciuresis. Do NOT give to dehydrated patient -worsens hypercalcemia.
📋 On Rounds
How do you distinguish hyperparathyroidism from malignancy as the cause?
PTH level. In primary hyperparathyroidism, PTH is elevated or inappropriately normal (should be suppressed by high calcium but isn't -the parathyroid adenoma is autonomously producing PTH). In malignancy, PTH is suppressed (low) because the hypercalcemia is driven by PTHrP, osteolytic metastases, or calcitriol -all of which suppress normal PTH via negative feedback.
Why does calcitonin lose effectiveness after 48 hours?
Tachyphylaxis from receptor downregulation. Calcitonin binds osteoclast calcitonin receptors, inhibiting bone resorption. With sustained exposure (> 48h), osteoclasts internalize and downregulate their calcitonin receptors -they become resistant to the drug. The clinical effect fades and calcium starts rising again. This is why calcitonin is a bridge agent -its fast onset (4–6h)
Why is furosemide no longer recommended for hypercalcemia treatment?
Old teaching: "NS + Lasix for hypercalcemia" -the idea was furosemide blocks calcium reabsorption in the Loop of Henle (calciuresis). Current evidence: furosemide is NOT recommended unless the patient is volume overloaded. Reasons: (1) Most hypercalcemia patients are severely volume depleted (hypercalcemia → nephrogenic DI → polyuria → dehydration). Giving furosemide before adequate volume repletion worsens dehydration → worsens hypercalcemia.
What is the approach to determining the etiology of hypercalcemia?
PTH is the branch point. Check PTH first. PTH elevated (or inappropriately normal): primary hyperparathyroidism (#1 cause of hypercalcemia in outpatients). Rarely: familial hypocalciuric hypercalcemia (FHH -check 24h urine calcium: FHH has low urine Ca, PHPT has high urine Ca), lithium-induced, parathyroid carcinoma. PTH suppressed (< 20): non-PTH-mediated.
What is the single most important test in the workup of hypercalcemia?
PTH. It's the diagnostic branch point. Elevated/normal PTH = PTH-mediated (90% primary hyperparathyroidism). Suppressed PTH = malignancy, granulomatous disease, or vitamin D toxicity.
Why should you NOT give furosemide as initial treatment for hypercalcemia?
Most patients are severely dehydrated from hypercalcemia-induced nephrogenic diabetes insipidus. Furosemide in a dehydrated patient worsens volume depletion and hypercalcemia. Rehydrate with NS first, then furosemide only if volume-overloaded.
A patient with sarcoidosis has hypercalcemia. Which medication treats it and why?
Prednisone -sarcoid macrophages express 1α-hydroxylase that converts 25-OH vitamin D to active 1,25-dihydroxy vitamin D. Steroids suppress this enzyme. Bisphosphonates are less effective because the mechanism is vitamin D-mediated, not bone resorption.
Why does calcitonin have tachyphylaxis at 48 hours?
Calcitonin receptors on osteoclasts become downregulated after 48h of continuous exposure. The Ca-lowering effect wanes. It's used only as a bridge while waiting for zoledronic acid to take effect (onset 2-4 days).
📣 Sample Presentation
One-Liner
"Mrs. Taylor is a 72-year-old with metastatic breast cancer presenting with confusion, constipation, and polyuria. Ca²⁺ 14.8 (corrected for albumin). PTH suppressed at 8. PTHrP pending."
Key Points to Cover on Rounds
Hypercalcemia of malignancy (PTH suppressed → not primary hyperparathyroidism). Most likely humoral hypercalcemia (PTHrP secretion from breast cancer). Treatment initiated: (1) NS at 250 mL/hr (volume expansion -first priority), (2) calcitonin 4 IU/kg IM q12h (fast onset, bridges to zoledronic acid, tachyphylaxis at 48h), (3) zoledronic acid 4 mg IV over 15 min (most effective long-term, onset 2-4 days). No furosemide unless volume overloaded. Ca trending 14.8→13.2→11.4 over 48h. Plan: oncology for disease-directed therapy, repeat Ca in 48h, denosumab if bisphosphonate fails.
Monitoring
Ionized calcium q6-12h during active treatment (more accurate than corrected Ca in critical illness, hypoalbuminemia, acid-base disorders)
BMP q12-24h -Cr (renal function during aggressive hydration), K⁺, Mg²⁺ (calcitonin can cause hypokalemia/hypomagnesemia)
Urine output q1-4h during initial hydration -target ≥ 100-150 mL/hr. Hypercalcemia causes nephrogenic DI → patients are severely volume-depleted
ECG -short QT interval, Osborn waves, bradycardia at very high levels. Monitor for QTc normalization
Repeat Ca²⁺ at 48h after zoledronic acid -onset 2-4 days, peak effect 4-7 days. Don't re-dose before day 7.
Phosphate -bisphosphonates can cause hypophosphatemia
Mental status -confusion, lethargy correlate with severity ("bones, stones, groans, psychiatric overtones")
Daily volume status -aggressive IVF can cause overload in CHF/CKD patients
⚡ Summary
Summary
One Test Splits the Whole Differential
Check PTH first, because primary hyperparathyroidism and malignancy together explain about 90% of hypercalcemia.Elevated or even inappropriately normal PTH is PTH-dependent disease: a normal PTH in the face of a high calcium is already abnormal, since a healthy gland would have shut off. Suppressed PTH means something else is driving the calcium: send PTHrP for humoral malignancy and 1,25-vitamin D for granulomatous disease or lymphoma, and review the med list (thiazides, lithium, calcium-alkali, vitamin D excess).
Outpatient #1: Primary Hyperparathyroidism
High calcium with a high or non-suppressed PTH, usually a single parathyroid adenoma. Typically mild and found on routine labs. Parathyroidectomy is the cure for symptomatic disease or guideline criteria (age under 50, calcium more than 1 above normal, osteoporosis or fracture, eGFR below 60, stones). Check a 24-hour urine calcium before referring for surgery: familial hypocalciuric hypercalcemia mimics the labs, causes no harm, and gains nothing from an operation.
Inpatient #1: Malignancy
The commonest cause of severe inpatient hypercalcemia, and the mechanism guides the workup: humoral PTHrP secretion (squamous cell cancers, renal cell, breast) in about 80%, direct osteolytic destruction (myeloma, breast metastases) in most of the rest, and tumor 1,25-vitamin D production (lymphoma), which is the one that responds to steroids. Calcium high enough to admit usually means disease advanced enough to see, so a normal PTHrP with an unremarkable exam should push toward myeloma workup and imaging.
Treatment Order, and Why That Order
(1) Normal saline 200 to 300 mL/h first and most important: hypercalcemia causes a nephrogenic diabetes insipidus plus vomiting, so every one of these patients is volume depleted, and restoring volume restores renal calcium excretion. (2) Calcitonin 4 IU/kg SC q12h works within hours but exhausts itself by 48 h (receptor tachyphylaxis), so it exists to bridge the gap. (3) Zoledronic acid 4 mg IV is the durable therapy, shutting down osteoclasts, with onset 2 to 4 days. No furosemide unless volume overloaded: it worsens the depletion that is driving the calcium. Steroids only for 1,25-D-mediated disease, where they cut the vitamin D activation.
Severe (Above 14) or Symptomatic
Run all three at once: aggressive saline, calcitonin for the first 48 h, and zoledronic acid on day one, because the bisphosphonate started today is what controls day four. ICU and telemetry for AMS or cardiac findings; the ECG clue is a short QT.Denosumab if bisphosphonate-refractory or renal failure blocks bisphosphonate use, and dialysis for the refractory patient with AKI who cannot receive the saline volume.
Symptoms: Stones, Bones, Groans, Moans
Renal stones, bone pain and fractures, abdominal pain with constipation and pancreatitis, and neuropsychiatric changes from depression to coma. Polyuria with thirst is the underrated one: calcium impairs the collecting duct's response to ADH (nephrogenic DI), which is exactly why these patients arrive dehydrated and why fluids come first. Severity tracks the speed of the rise more than the number: a slow drift to 12 may be silent while a rapid rise to the same level is not.
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CoreEndocrinology
Corticosteroids
Complete guide to systemic corticosteroids, glucocorticoid vs mineralocorticoid potency, equivalent dosing, duration of action, and when to choose which steroid. A high-yield reference that crosses every rotation.
🔍 Overview
Glucocorticoid vs Mineralocorticoid Activity
Glucocorticoid activity, anti-inflammatory, immunosuppressive, metabolic (gluconeogenesis, protein catabolism, fat redistribution). This is the effect you want for most indications (asthma, autoimmune disease, cerebral edema, etc.).
Mineralocorticoid activity, sodium retention, potassium excretion, volume expansion. Desired in adrenal insufficiency (replaces aldosterone), but an unwanted side effect in most other settings (causes edema, hypertension, hypokalemia).
Key principle: All corticosteroids have BOTH activities in varying ratios. Choosing the right steroid means matching the glucocorticoid:mineralocorticoid profile to the clinical scenario.
Duration of Action Categories
Category
Biologic Half-Life
Examples
Clinical Implication
Short-acting
8–12 hours
Hydrocortisone (Solu-Cortef), Cortisone
Most physiologic. Mimics endogenous cortisol. Best for replacement therapy. Must dose BID-TID.
Workhorse steroids. Daily or BID dosing. Most common for anti-inflammatory use.
Long-acting
36–72 hours
Dexamethasone (Decadron), Betamethasone
Most potent per mg. No mineralocorticoid activity. Daily dosing. Greatest HPA axis suppression.
📊 Equivalency Table
Steroid Equivalency & Potency Comparison
How to read this table: All doses shown are equivalent to 20 mg hydrocortisone (the body's daily physiologic cortisol output). A higher glucocorticoid potency number means you need LESS drug for the same anti-inflammatory effect.
Steroid
Equivalent Dose
Glucocorticoid Potency vs Hydrocortisone (1×)
Mineralocorticoid Potency vs Hydrocortisone (1×)
Biologic Half-Life
Duration
Hydrocortisone (Solu-Cortef) Most physiologic, identical to endogenous cortisol
20 mg
1×
1×
8–12 h
Short
Cortisone Prodrug → converted to hydrocortisone in liver
25 mg
0.8×
0.8×
8–12 h
Short
Prednisone Most commonly prescribed oral steroid
5 mg
4×
0.6×
12–36 h
Intermediate
Prednisolone Active form of prednisone, use in liver failure
5 mg
4×
0.6×
12–36 h
Intermediate
Methylprednisolone (Solu-Medrol) IV steroid of choice, less mineralocorticoid than prednisone
4 mg
5×
0.5×
12–36 h
Intermediate
Triamcinolone (Kenalog) Common for intra-articular injections
4 mg
5×
0×
12–36 h
Intermediate
Dexamethasone (Decadron) Most potent, zero mineralocorticoid activity
0.75 mg
25–30×
0×
36–72 h
Long
Betamethasone (Celestone) Used for fetal lung maturity in preterm labor
0.75 mg
25–30×
0×
36–72 h
Long
Fludrocortisone (Florinef) Mineralocorticoid replacement, NOT used for anti-inflammatory effect
N/A
10×
125×
18–36 h
Intermediate
Fludrocortisone is used purely for mineralocorticoid replacement in primary adrenal insufficiency (0.05–0.2 mg daily). Despite having glucocorticoid potency, it is NEVER used as an anti-inflammatory agent because the mineralocorticoid side effects (Na⁺ retention, K⁺ wasting, HTN) would be unacceptable at those doses.
🏥 Clinical Use
When to Use Which Steroid
Clinical Scenario
Steroid of Choice
Why This One
Adrenal crisis / insufficiency replacement Most common steroid question on rounds
Hydrocortisone 100 mg IV bolus → 50 mg q8h
Most physiologic. Provides BOTH glucocorticoid AND mineralocorticoid coverage. Mimics endogenous cortisol. Endocrine Society, 2016
Adrenals cannot mount an adequate cortisol response to physiologic stress. Suspect in vasopressor-dependent shock not responding to fluids and pressors. Random cortisol <10 in critical illness is suggestive. SSC, 2021/2026: start steroids for septic shock with ongoing vasopressor requirement. APROCCHSS, 2018
Adrenal insufficiency, need cosyntropin stim test
Dexamethasone 4 mg IV q12h
Does NOT cross-react with cortisol assay → lets you treat the patient AND still get a valid cosyntropin stimulation test result. Switch to hydrocortisone once diagnosis confirmed.
Cerebral edema / increased ICP
Dexamethasone 10 mg IV load → 4 mg q6h
Most potent anti-inflammatory. Zero mineralocorticoid activity = no sodium/water retention that would worsen cerebral edema. Galicich & French, 1961
Bacterial meningitis (adjunctive)
Dexamethasone 0.15 mg/kg q6h × 4 days
Reduces inflammation and hearing loss. Must give BEFORE or WITH first antibiotic dose. de Gans, 2002
COPD exacerbation
Methylprednisolone 125 mg IV (inpatient) OR Prednisone 40 mg PO daily × 5 days
IV methylprednisolone for acute ED/inpatient management, then transition to PO prednisone 40 mg daily to complete a 5-day course. REDUCE, 2013GOLD, 2024
Asthma exacerbation
Prednisone 40–60 mg PO daily × 5–7 days OR Dexamethasone 16 mg PO × 2 days
Dex option emerging as single-dose/2-day alternative in ED. Prednisone is traditional standard. Rehrer, 2016
Autoimmune flare (SLE, vasculitis, etc.)
Methylprednisolone 1g IV daily × 3 days ("pulse"), then Prednisone taper
IV pulse for rapid immunosuppression. Methylprednisolone preferred IV, less mineralocorticoid than hydrocortisone at high doses. EULAR, 2020
Spinal cord compression
Dexamethasone 10 mg IV load → 4 mg q6h
Same rationale as cerebral edema, maximal anti-inflammatory, no fluid retention.
Croup
Dexamethasone 0.6 mg/kg PO/IM × 1 dose
Long half-life = single dose sufficient. Well-studied in pediatrics. Bjornson, Cochrane 2013
Thyroid storm
Hydrocortisone 100 mg IV q8h
Blocks peripheral T4→T3 conversion. Treats relative adrenal insufficiency from hypermetabolic state. Mineralocorticoid activity is acceptable here. ATA, 2016
Septic shock (refractory)
Hydrocortisone 50 mg IV q6h × 7 days
Low-dose stress steroids for vasopressor-refractory shock. SSC, 2021/2026ADRENAL, 2018APROCCHSS, 2018
Fetal lung maturity (preterm labor)
Betamethasone 12 mg IM × 2 doses 24h apart
Crosses placenta effectively. No mineralocorticoid activity. Standard of care 24–34 weeks gestation. Liggins & Howie, 1972
Hydrocortisone for glucocorticoid + some mineralocorticoid. Fludrocortisone added because primary AI loses both cortisol AND aldosterone. Endocrine Society, 2016
Chronic replacement (secondary AI)
Hydrocortisone 15–20 mg AM + 5–10 mg PM
No fludrocortisone needed, aldosterone production is preserved (renin-angiotensin axis intact).
Liver failure patient needing steroids
Prednisolone or Methylprednisolone
Prednisone is a prodrug that requires hepatic conversion to prednisolone. In liver failure, use the active form directly.
Key Clinical Pearls
Prednisone vs Prednisolone: Prednisone is a prodrug, the liver converts it to active prednisolone. In severe liver disease or hepatic failure, use prednisolone (or methylprednisolone IV) directly since the conversion may be impaired.
Dexamethasone + cosyntropin stim test: When you suspect adrenal insufficiency but want to treat BEFORE confirming, use dexamethasone instead of hydrocortisone. Dex does NOT cross-react with the cortisol assay used in the cosyntropin stimulation test, so you can treat and test simultaneously.
Mineralocorticoid effects at high doses: Even steroids with "low" mineralocorticoid potency (like prednisone) can cause significant Na⁺ retention, edema, and HTN when used at high doses (≥40 mg/day). This is why methylprednisolone or dexamethasone are preferred for high-dose IV pulse therapy, minimal mineralocorticoid effect.
⚠️ Side Effects
Adverse Effects by System
System
Effect
Mechanism / Notes
Metabolic Most common overall
Hyperglycemia, insulin resistance
Gluconeogenesis + peripheral insulin resistance. Check BG q6h on all inpatients started on steroids. May need sliding scale or basal insulin adjustment. RABBIT 2, 2011
Musculoskeletal
Osteoporosis, avascular necrosis, myopathy
Bone: inhibits osteoblasts + Ca²⁺ absorption. Start calcium + vitamin D + consider bisphosphonate if ≥3 months of prednisone ≥7.5 mg/day. AVN: hip most common. ACR, 2022
Infectious
Immunosuppression, opportunistic infections
PJP prophylaxis (TMP-SMX) if prednisone ≥20 mg/day for ≥1 month. Reactivation risk: TB, strongyloides, HBV. IDSA/ATS Guidelines
Inhibits collagen synthesis. Counsel patients on increased skin fragility.
Three things to do for EVERY patient started on steroids: (1) Check blood glucose q6h and cover with insulin. (2) Start GI prophylaxis if also on NSAIDs or anticoagulants. (3) Plan the taper from day one, do not start steroids without an exit strategy.
📉 Tapering
When to Taper vs Abrupt Stop
Can stop abruptly: Short course (≤2 weeks) at any dose, OR low dose (≤10 mg prednisone) for any duration, OR alternate-day regimen.
Must taper: ≥20 mg prednisone equivalent daily for ≥3 weeks. Also taper if ANY duration on supraphysiologic doses AND the patient has Cushingoid features or symptoms of HPA suppression.
General rule: The longer the patient was on steroids, the slower the taper. There is no single correct taper, individualize based on the disease being treated and the patient's symptoms.
Sample Taper Strategies
Starting Dose
Taper Approach
Notes
Prednisone ≥40 mg/day
Decrease by 10 mg every 1–2 weeks until 20 mg, then by 5 mg every 1–2 weeks until 10 mg, then by 2.5 mg every 1–2 weeks
Slower taper below 10 mg, this is where HPA axis recovery happens
Prednisone 20–40 mg/day
Decrease by 5 mg every 1–2 weeks until 10 mg, then by 2.5 mg every 1–2 weeks
Watch for disease flare and adrenal insufficiency symptoms during taper
Signs of too-fast taper: fatigue, malaise, arthralgias, myalgias, nausea, orthostatic hypotension. These may represent adrenal insufficiency OR disease flare, check an AM cortisol to differentiate. If cortisol low → slow the taper. If cortisol normal → likely disease flare → increase dose back up.
🩺 Rounds
Pimp Questions
Why do you use dexamethasone instead of hydrocortisone when you still need to confirm adrenal insufficiency with a cosyntropin stim test?
Hydrocortisone IS cortisol, it cross-reacts with the cortisol immunoassay and will falsely elevate the measured cortisol level, invalidating the stim test results. Dexamethasone is a synthetic steroid that does NOT cross-react with the cortisol assay, so you can treat the patient and still get an accurate stim test.
Why is methylprednisolone preferred over hydrocortisone for IV pulse therapy in autoimmune disease?
At high pulse doses (500–1000 mg), hydrocortisone's mineralocorticoid activity would cause massive sodium and water retention, hypertension, and hypokalemia. Methylprednisolone has minimal mineralocorticoid activity, so you get the immunosuppression without the volume overload.
A patient with cirrhosis needs steroids for an autoimmune hepatitis flare. Why should you use prednisolone instead of prednisone?
Prednisone is a prodrug that requires hepatic conversion to its active form, prednisolone. In a patient with severe liver disease, this conversion may be impaired, leading to a subtherapeutic response. Prednisolone is already the active form and bypasses this step.
Why does primary adrenal insufficiency require fludrocortisone but secondary does not?
In primary AI, the adrenal gland itself is destroyed → you lose BOTH cortisol (glucocorticoid) AND aldosterone (mineralocorticoid). Fludrocortisone replaces the missing aldosterone. In secondary AI, the problem is pituitary ACTH deficiency → cortisol drops, but aldosterone production is still intact because it is regulated by the renin-angiotensin system, NOT ACTH.
What is the physiologic daily cortisol output, and which steroid dose is equivalent?
The body produces ~15–25 mg of cortisol daily (average ~20 mg). This equals hydrocortisone 20 mg, prednisone 5 mg, methylprednisolone 4 mg, or dexamethasone 0.75 mg. Anything above this is "supraphysiologic" and carries risk of HPA axis suppression with chronic use.
Why is dexamethasone the steroid of choice for cerebral edema and not hydrocortisone?
Dexamethasone has ZERO mineralocorticoid activity, no sodium or water retention. Hydrocortisone would worsen cerebral edema through its mineralocorticoid effect. Dex is also the most potent glucocorticoid per mg (25–30× hydrocortisone), giving maximum anti-inflammatory effect with minimum volume.
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ChronicRheumatology
Rheumatoid Arthritis
Symmetric inflammatory polyarthritis of the small joints. Early aggressive treatment with DMARDs prevents joint destruction. "Treat to target" -remission or low disease activity. Know the extra-articular manifestations and drug monitoring.
🔍 Overview
Diagnosis
Symmetric polyarthritis of small joints: MCPs, PIPs, wrists, MTPs. Spares DIPs (DIP involvement → think OA or psoriatic).
Morning stiffness > 30 minutes (improves with use -opposite of OA which worsens with use)
Labs: RF (sensitive ~70%, not specific), anti-CCP (most specific ~95%), ESR, CRP elevated. Anti-CCP negative RA exists (seronegative -harder to diagnose).
Imaging: X-ray hands/feet -periarticular osteopenia, joint space narrowing, marginal erosions (late). US or MRI for early synovitis detection.
💊 Treatment
Line
Drug
Monitoring
Key Notes
1ST LINE
Methotrexate (Trexall) 15–25 mg PO/SC weekly
CBC, LFTs, Cr q3 months. CXR at baseline (ILD screening).
Cornerstone of RA treatment. Always give with folic acid 1 mg daily (reduces GI/oral side effects). Teratogenic -contraception required. Avoid in liver disease, heavy EtOH. Hold for surgery (infection risk).
ADD-ON
Hydroxychloroquine (Plaquenil) 200–400 mg daily
Annual eye exam (retinal toxicity after 5 years)
Mild disease or combination therapy. Very safe. Also used in SLE.
ADD-ON
Sulfasalazine 2–3g daily
CBC, LFTs
Triple therapy (MTX + HCQ + SSZ) is as effective as many biologics for moderate RA.
Screen for TB (QuantiFERON), Hep B/C, HIV before starting. Annual TB screening.
Add to MTX if inadequate response. Hold for active infection and peri-operatively. Risk: TB reactivation, serious infections, lymphoma (small increase).
BIOLOGIC
IL-6 inhibitor (tocilizumab), JAK inhibitor (tofacitinib, upadacitinib)
CBC, LFTs, lipids. JAKi: screen for VTE risk.
Alternatives if TNFi fails. JAK inhibitors: FDA black box for VTE, MACE, and malignancy in age > 65 ORAL Surveillance, 2022 -use after biologic failure.
Screen for TB before ANY biologic or JAK inhibitor. TNF is critical for granuloma maintenance -TNF inhibition can reactivate latent TB. QuantiFERON-Gold or PPD. If positive → treat latent TB (isoniazid × 9 months or rifampin × 4 months) for ≥ 1 month before starting biologic.
🚨 Management
Management
Goal: Remission or low disease activity within 6 months -treat-to-targetTICORA, 2004. Check DAS28 or CDAI q3 months. Adjust until target reached.
First-line: Methotrexate 15-25 mg/week PO or SQ + folic acid 1 mg daily (reduces side effects without reducing efficacy). Start 15 mg, escalate to 25 mg by week 8 if tolerated. SQ has better bioavailability at higher doses.
Bridge therapy: Low-dose prednisone ≤ 10 mg daily while waiting for DMARD effect (4-12 weeks). Taper ASAP -goal is OFF steroids. Depo-medrol intra-articular for 1-2 dominant joints.
If inadequate at 3 months on max MTX: Add biologic DMARD:
TNF inhibitors (adalimumab, etanercept, infliximab) -most commonly used first-line biologics
Non-TNF biologics: tocilizumab (IL-6), abatacept (T-cell co-stim), rituximab (anti-CD20, especially if RF/CCP positive)
JAK inhibitors: tofacitinib, upadacitinib, baricitinib -oral, fast onset. FDA box warning: ↑ VTE, MACE, malignancy in pts > 50 with CV risk factors ORAL Surveillance, 2022
Pre-biologic checklist: QuantiFERON (TB), HBV/HCV serologies, update vaccines (no live vaccines on biologics), CXR
Monitoring on MTX: CBC + CMP q4-8 weeks first 3 months, then q8-12 weeks. Hold MTX if transaminases > 2× ULN. Avoid alcohol. Contraception required (teratogenic -hold 3 months before conception).
📋 On Rounds
An RA patient on methotrexate is admitted with pneumonia. What do you do with the methotrexate?
Hold methotrexate during active infection. MTX is an immunosuppressant -continuing it impairs the patient's ability to fight the infection. Also hold if: surgery planned (increased wound healing complications), new cytopenias (check CBC), or rising LFTs. Resume once infection is treated and patient is clinically improving. Do NOT hold hydroxychloroquine -it has minimal immunosuppression and should be continued through illness.
Why do you check hepatitis B and TB before starting a biologic in RA?
Biologics (TNF inhibitors like adalimumab, infliximab; IL-6 inhibitors like tocilizumab; B-cell depleting agents like rituximab) cause profound immunosuppression that can reactivate latent infections. Hepatitis B: TNF inhibitors can cause fatal HBV reactivation (fulminant hepatitis) -check HBsAg, anti-HBs, anti-HBc. If HBsAg+ or anti-HBc+ → start antiviral prophylaxis (entecavir or tenofovir) before starting biologic.
What is the treat-to-target approach in RA?
Goal: remission or low disease activity within 6 months. Start methotrexate (first-line DMARD, 15-25 mg/week + folic acid 1 mg daily). Reassess at 3 months: if not at target → add or switch therapy. Options: (1) Add biologic (TNFi: adalimumab, etanercept; or non-TNF: tocilizumab, abatacept, rituximab), (2) Add JAK inhibitor (tofacitinib, upadacitinib -oral, convenient, but risk of VTE/MACE at higher doses).
What monitoring is needed for a patient on methotrexate for RA?
Before starting: CBC, CMP (LFTs, Cr), hepatitis B/C serologies, chest X-ray (baseline for pulmonary toxicity), pregnancy test (teratogenic -Category X). Ongoing monitoring (every 2-3 months initially, then q3-6 months when stable): CBC (pancytopenia -bone marrow suppression), LFTs (hepatotoxicity -hold if AST/ALT > 2× ULN), Cr (renal clearance -dose reduce if CrCl declining).
What is the most specific antibody for RA?
Anti-CCP (anti-citrullinated peptide) -~95% specific. Can be positive years before symptoms. High titer predicts more aggressive, erosive disease. RF is sensitive (~80%) but not specific.
A patient with RA on methotrexate for 3 months still has active disease. What's next?
Add a biologic DMARD (TNF inhibitor like adalimumab, or non-TNF like tocilizumab/abatacept). Per treat-to-target guidelines, if target not met at 3 months → escalate. If still not met at 6 months → switch class.
Why are DOACs inferior to warfarin in antiphospholipid syndrome?
The TRAPS trial [2018] was stopped early because rivaroxaban had significantly more arterial thrombotic events than warfarin in triple-positive APS. ASTRO-APS confirmed. The mechanism: DOACs don't adequately block the thrombin generation pathway in APS.
Which RA medication is safe in pregnancy?
Sulfasalazine and hydroxychloroquine are safe. Certolizumab (Fc-free anti-TNF) has minimal placental transfer. Methotrexate is category X -stop 3 months before conception. Leflunomide has a very long half-life -needs cholestyramine washout.
Clinical Examples
📋 Case 1, Methotrexate Pneumonitis
Patient: 56-year-old woman with seropositive RA on methotrexate 20 mg/week × 2 years, presenting with 1 week of progressive dyspnea, dry cough, and low-grade fever. No sick contacts.
Stop methotrexate immediately, methotrexate pneumonitis (hypersensitivity, not dose-dependent)
Prednisone 1 mg/kg daily with taper over 4-6 weeks
Rule out PJP, RA-ILD, and infection
Do NOT rechallenge with MTX, switch to leflunomide or biologic
Teaching point: MTX pneumonitis can occur at any time. It is a hypersensitivity reaction, not dose-related. Acute onset and temporal relationship to MTX distinguishes it from RA-ILD. Never rechallenge.
📋 Case 2, Biologic Initiation with Latent TB
Patient: 48-year-old man with RA, inadequate response to methotrexate 25 mg/week × 6 months (DAS28 = 5.1). Rheumatology recommends adalimumab. Pre-biologic screening: QuantiFERON POSITIVE. CXR normal.
Key findings: Latent TB identified. No active disease. HBsAg negative, anti-HBc negative.
Hold adalimumab AND methotrexate during active infection
Continue hydroxychloroquine, minimal immunosuppression, safe during illness
Treat cellulitis: IV cefazolin → oral cephalexin
For RA flare: prednisone 20 mg × 5 days (acceptable during infection at moderate doses)
Resume biologics only after infection fully resolved
Teaching point: Holding biologics during infection is mandatory. HCQ is the one DMARD safe to continue through most infections. Do not restart biologics too early, ensure complete clinical resolution.
📣 Sample Presentation
One-Liner
"Mrs. Patterson is a 42-year-old with seropositive RA on methotrexate 20 mg weekly who presents with 3 weeks of worsening bilateral hand and wrist swelling and morning stiffness >2 hours. CRP 4.8, ESR 62. Active flare."
Key Points to Cover on Rounds
RA flare on methotrexate monotherapy. DAS28 score indicates high disease activity. Treatment: prednisone 20 mg PO burst × 5 days for acute symptom control. Rheumatology consulted -plan to add biologic (adalimumab or tocilizumab). Pre-biologic workup: QuantiFERON (TB), HBsAg, anti-HBs, anti-HBc (hepatitis B reactivation risk), hepatitis C, CBC, LFTs. Immunizations: flu, pneumococcal, COVID -updated before starting biologic. Plan: taper prednisone, initiate biologic when screening complete, repeat CRP in 4 weeks.
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
Monitoring
DAS28 or CDAI score q3 months -standardized disease activity tracking. Adjust treatment to target.
CBC, CMP (LFTs, Cr) q8-12 weeks on MTX -hepatotoxicity, cytopenias, renal function
X-rays hands/feet annually first 3 years -structural damage progression
Lipids -check at baseline and periodically on tocilizumab and JAK inhibitors
Infection vigilance -on biologics/JAKi: annual flu + pneumococcal vaccines (inactivated only). Low threshold for workup of fever.
Cervical spine X-ray -if surgery planned (atlantoaxial subluxation risk in severe RA)
CV risk assessment -RA is an independent CV risk factor. Multiply Framingham score by 1.5.
🧪 Workup
Workup
RF (rheumatoid factor) -sensitive (~80%) but not specific. Also positive in Sjögren's, HCV, endocarditis, elderly.
Anti-CCP (anti-citrullinated peptide) -most specific for RA (~95%). Can be positive years before symptoms. High titer = more aggressive/erosive disease.
ESR + CRP -baseline disease activity markers. CRP more responsive to treatment changes.
CBC, BMP, LFTs -baseline before starting DMARDs. Anemia of chronic disease common.
Hepatitis B/C serologies -before methotrexate or biologics (reactivation risk)
QuantiFERON/PPD -latent TB screening before biologics (especially TNF inhibitors)
X-rays of hands/feet -baseline. Periarticular osteopenia, joint space narrowing, marginal erosions. Erosions within first 2 years in 70% untreated.
Musculoskeletal ultrasound -synovitis, erosions earlier than X-ray. Increasingly used for subclinical inflammation.
Joint distribution -symmetric small joint polyarthritis (MCPs, PIPs, wrists, MTPs). Spares DIPs (DIP involvement = think OA or psoriatic arthritis).
💊 Medications
Medications
Drug
Dose
Route
Notes
Conventional DMARDs
Methotrexate
15-25 mg/week
PO/SQ
First-line DMARD -anchor drug. Start with folic acid 1 mg daily (reduces GI + oral ulcer side effects). SQ better absorbed at doses > 15 mg. Monitor: CBC, LFTs, Cr q8-12 weeks. Teratogenic (category X) -stop 3 months before conception.
Leflunomide
20 mg daily
PO
Alternative to MTX if intolerant. Pyrimidine synthesis inhibitor. Very long half-life (14 days). Cholestyramine washout if toxicity or pregnancy planned.
Sulfasalazine
1-1.5g BID
PO
Mild RA or combination therapy. Safe in pregnancy (one of few DMARDs). Check G6PD.
Hydroxychloroquine
200-400 mg daily
PO
Mild RA, often combined with MTX. Annual retinal screening after 5 years.
Biologic DMARDs -add if inadequate response to MTX at 3 months
Adalimumab
40 mg SQ q2 weeks
SQ
TNF inhibitor. Most prescribed biologic. Screen TB/HBV before starting. Risk: serious infections, reactivation TB, lymphoma (rare).
Etanercept
50 mg SQ weekly
SQ
TNF inhibitor (receptor fusion protein). Less TB reactivation risk than monoclonal anti-TNFs. Does NOT work for IBD (unlike other TNFis).
Tocilizumab
162 mg SQ weekly or 8 mg/kg IV monthly
SQ/IV
Anti-IL-6 receptor. Suppresses CRP (can mask infection). Monitor lipids (LDL ↑), neutrophils, LFTs. Risk of GI perforation.
Abatacept
125 mg SQ weekly
SQ
T-cell costimulation blocker (CTLA-4 Ig). Generally well tolerated. Good safety profile in elderly.
Rituximab
1000 mg IV × 2 doses (day 1 + day 15)
IV
Anti-CD20 (B-cell depletion). Usually reserved for refractory RA after TNFi failure. Screen HBV. Monitor immunoglobulins.
JAK Inhibitors -oral targeted synthetic DMARDs
Tofacitinib
5 mg BID
PO
JAK1/3 inhibitor. FDA boxed warning: increased CV events + malignancy vs TNFi in patients ≥ 50 with CV risk ORAL Surveillance, 2022. Use after TNFi failure.
Upadacitinib
15 mg daily
PO
Selective JAK1 inhibitor. Superior to adalimumab in SELECT-COMPARE. Same FDA boxed warning class. VTE risk.
Treat-to-target: reassess disease activity (DAS28, CDAI) every 3 months. If target not met at 3 months → escalate. If target not met at 6 months → switch class. Goal: remission or low disease activity.
⚡ Summary
Summary
Recognize the Pattern
Symmetric inflammatory polyarthritis of the small joints, MCPs, PIPs and wrists, with morning stiffness beyond an hour.The DIP joints are spared, which separates it from osteoarthritis and psoriatic arthritis. Anti-CCP is the more specific antibody and predicts erosive disease; rheumatoid factor is less specific and occurs in hepatitis C, Sjogren and healthy older people.
Start DMARDs Early
The window in which joint destruction is preventable is the first months.Methotrexate is the anchor drug, with folic acid, and it is escalated rather than left at a token dose. Steroids are a bridge while the DMARD takes effect, never the long-term plan.NSAIDs relieve symptoms and do not prevent erosion.
Treat to Target
Reassess disease activity (DAS28 or CDAI) every 3 months.Target not met at 3 months means escalate; not met at 6 months means switch class.Aim for remission or low disease activity, and the discipline of scheduled reassessment is what distinguishes treat-to-target from drifting on an inadequate regimen.
Screen for TB Before Any Biologic or JAK Inhibitor
TNF maintains granulomas, so TNF inhibition reactivates latent tuberculosis.QuantiFERON-Gold or PPD, and treat latent TB (isoniazid for 9 months or rifampin for 4) before starting. Also screen hepatitis B and C, since biologics reactivate HBV.
Know the Monitoring for Each Drug
Methotrexate: CBC and liver tests every 8 to 12 weeks; hepatotoxicity, cytopenias, pneumonitis, and absolutely contraindicated in pregnancy. Leflunomide: liver tests, teratogenic with a very long half-life needing cholestyramine washout. Hydroxychloroquine: annual retinal screening. Sulfasalazine: CBC and liver tests. The monitoring is not optional paperwork: it is what makes long-term use safe.
Be Aware of the JAK Inhibitor Warning
ORAL Surveillance found higher rates of major cardiovascular events, malignancy, thrombosis and death with tofacitinib compared with a TNF inhibitor in patients over 50 with a cardiovascular risk factor. Reserve JAK inhibitors for patients who have failed a TNF inhibitor, and discuss the risk explicitly with older patients and smokers.
Look for the Extra-Articular Disease
Interstitial lung disease, which drives much of the mortality; pericarditis; scleritis and episcleritis; rheumatoid nodules; Felty syndrome (RA with splenomegaly and neutropenia); secondary Sjogren; and vasculitis.Cardiovascular disease is the leading cause of death, from the chronic inflammation itself, so aggressive risk-factor management is part of RA care.
Check the Cervical Spine Before Intubation
Atlantoaxial subluxation is common in long-standing RA and can cause cord compression on neck extension.Get flexion-extension cervical films before any general anesthetic, and warn the anesthesia team. This is the RA complication most likely to be catastrophic and most likely to be forgotten.
Autoimmune prothrombotic disorder. Triple-positive APS has highest risk. Warfarin is the standard, DOACs contraindicated (TRAPS trial). Catastrophic APS = multi-organ thrombosis requiring triple therapy.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Diagnostic Criteria (Revised Sapporo)
Requires ≥ 1 clinical criterion + ≥ 1 lab criterion, with lab confirmed on 2 occasions ≥ 12 weeks apart.
Clinical Criteria (≥ 1)
Lab Criteria (≥ 1, confirmed × 2)
Vascular thrombosis: arterial, venous, or small vessel thrombosis in any organ (DVT, PE, stroke, MI, renal/hepatic thrombosis)
Lupus anticoagulant (LA) -most strongly associated with thrombosis
Pregnancy morbidity: ≥ 1 unexplained fetal death ≥ 10 weeks, ≥ 3 unexplained consecutive losses < 10 weeks, premature birth < 34 weeks due to eclampsia/placental insufficiency
Anticardiolipin (aCL) IgG or IgM -medium-high titer
Anti-β2 glycoprotein I IgG or IgM
Triple-positive APS (all 3 antibodies positive) has the highest thrombotic risk. DOACs are CONTRAINDICATED in APS -TRAPS, 2018 showed rivaroxaban was inferior to warfarin with more thrombotic events. Warfarin is the standard.
Why is the aPTT prolonged in APS if the patient is actually prothrombotic?
The lupus anticoagulant binds to phospholipids that are used as reagents in the aPTT assay. In the test tube, this binding interferes with the phospholipid-dependent coagulation cascade → prolonged aPTT in vitro. But in vivo, these same antibodies bind endothelial cell phospholipids, activate complement, inhibit natural anticoagulants (protein C, annexin V), and activate platelets and monocytes → prothrombotic state.
Why are DOACs contraindicated in antiphospholipid syndrome?
The TRAPS trial (2018) was stopped early for safety -triple-positive APS patients randomized to rivaroxaban had significantly more thrombotic events (including stroke and MI) than those on warfarin.
What is catastrophic APS (CAPS) and how do you treat it?
What lab tests confirm APS and why do you need them positive twice?
3 antibodies: (1) Lupus anticoagulant (LA) -functional assay (prolonged aPTT that doesn't correct with mixing study). (2) Anticardiolipin antibodies (aCL) -IgG and IgM, medium-to-high titer. (3) Anti-β2-glycoprotein I (anti-β2GP1) -IgG and IgM. Must be positive on ≥ 2 occasions, at least 12 weeks apart -because transient positivity occurs with infections (HIV, hepatitis, syphilis), medications, and acute thrombotic events.
Why must antiphospholipid antibodies be confirmed at 12 weeks?
Transient aPL positivity occurs commonly during infections, medications, and other acute illnesses. Persistent positivity (≥ 12 weeks apart on 2 occasions) is required for diagnosis to avoid overdiagnosis and unnecessary lifelong anticoagulation.
What is catastrophic APS (CAPS)?
Multi-organ failure developing over < 1 week due to widespread small-vessel thrombosis. ~50% mortality. Affects ≥ 3 organ systems simultaneously. Treat with triple therapy: anticoagulation + high-dose steroids + PLEX or IVIG.
What is the standard regimen for obstetric APS?
Low-dose ASA (81 mg) started preconception + prophylactic LMWH (enoxaparin 40 mg daily) added once pregnancy confirmed. This reduces pregnancy loss from ~70% to ~20-30%.
Which APS patients are highest risk for recurrent thrombosis?
Triple-positive patients (lupus anticoagulant + anticardiolipin + anti-β2GP1 all positive). These patients need lifelong anticoagulation -never stop. Single positivity has lower (but not zero) recurrence risk.
Clinical Examples
📋 Case 1, Triple-Positive APS with Recurrent DVT
Patient: 34-year-old man with known triple-positive APS on warfarin, presenting with new left leg swelling. INR 1.4 (subtherapeutic, missed doses). Compression US confirms acute proximal DVT.
Key findings: Triple-positive: LA+, aCL IgG 82 GPL, anti-β2GP1 IgG+. Prior DVT 2 years ago. No SLE features.
Management:
Start heparin drip immediately (bridge to therapeutic warfarin)
Target INR 2-3 (some experts target 3-4 for recurrent events on therapeutic INR) TRAPS, 2018
No DOACs, contraindicated in APS (TRAPS showed excess thrombosis with rivaroxaban)
Add hydroxychloroquine 200 mg daily (antithrombotic properties in APS)
Lifelong warfarin, never stop in triple-positive APS
Teaching point: Triple-positive APS has the highest thrombotic risk. DOACs are absolutely contraindicated. Warfarin adherence is critical, even brief subtherapeutic periods can lead to recurrent events.
📋 Case 2, Catastrophic APS (CAPS)
Patient: 28-year-old woman with known APS (single-positive aCL), hospitalized for pneumonia. Over 3 days develops acute renal failure (Cr 1.0 → 4.2), altered mental status, thrombocytopenia (platelets 38K), and livedo reticularis with digital ischemia.
Key findings: Schistocytes on smear. LDH 1,200. Multi-organ thrombosis on imaging: renal infarcts, cerebral microthrombi on MRI. Infection triggered CAPS.
Management:
Triple therapy for CAPS: (1) Heparin drip, (2) Methylprednisolone 1g IV × 3 days, (3) Plasma exchange (PLEX) daily × 5-7 days
Continue treating the trigger (antibiotics for pneumonia)
If refractory → add rituximab or eculizumab (complement inhibitor)
ICU admission, mortality 30-50% even with treatment
Teaching point: CAPS = multi-organ thrombosis developing in less than 1 week. Most often triggered by infection, surgery, or anticoagulation withdrawal. Recognize by the pattern: ≥ 3 organ systems + microvascular thrombosis + known aPL.
📋 Case 3, Obstetric APS
Patient: 31-year-old woman with 3 consecutive first-trimester miscarriages. No prior thrombosis. Workup reveals persistent anticardiolipin IgG (52 GPL) and anti-β2GP1 IgG positive on two occasions 14 weeks apart. LA negative.
Key findings: Meets criteria for obstetric APS: ≥ 3 consecutive pregnancy losses before 10 weeks + persistent aPL positivity (confirmed at ≥ 12 weeks).
Teaching point: Obstetric APS requires persistent aPL positivity on 2 tests ≥ 12 weeks apart to avoid overdiagnosis from transient infection-related positivity. ASA + LMWH is the standard regimen. Warfarin is teratogenic, must switch to LMWH.
📣 Sample Presentation
One-Liner
"Mr. Garcia is a 38-year-old with triple-positive APS (LA+, aCL+, anti-β2GP1+) on warfarin who presents with INR 1.3 and new left leg DVT on compression ultrasound."
Key Points to Cover on Rounds
Recurrent thrombosis in known triple-positive APS -INR subtherapeutic at 1.3 (goal 2-3). Acute DVT management: heparin drip started (bridge to therapeutic warfarin). INR target remains 2-3 -some experts recommend 3-4 for recurrent events on therapeutic warfarin. No DOACs (contraindicated in APS TRAPS, 2018). Adding hydroxychloroquine (reduces thrombosis risk in APS, especially SLE-associated). Warfarin adherence and diet counseled. Plan: lifelong warfarin, rheumatology follow-up, consider adding low-dose ASA if arterial events occur.
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
🧪 Workup
Workup
Lupus anticoagulant (LA) -functional assay (dRVVT or PTT-LA). Paradoxically prolongs aPTT but is PROthrombotic. Most specific of the 3 tests.
Anticardiolipin antibodies (IgG and IgM) -ELISA. Titers > 40 GPL/MPL are clinically significant.
Anti-β2-glycoprotein I (IgG and IgM) -ELISA. Associated with thrombosis + obstetric complications.
Repeat positive at 12 weeks -diagnosis requires positive on 2 occasions ≥ 12 weeks apart (transient positivity in infections is common).
First-line for thrombotic APS. Lifelong after first event. DOACs are INFERIOR to warfarin in APS -TRAPS trial stopped early for excess arterial events with rivaroxaban TRAPS, 2018. ASTRO-APS confirmed: use warfarin, not DOACs.
Heparin (LMWH)
Enoxaparin 1 mg/kg BID
SQ
Acute thrombosis treatment, bridge to warfarin. Also used in obstetric APS.
ASA
81 mg daily
PO
Primary prevention in asymptomatic aPL-positive patients (especially with SLE). Added to warfarin for arterial events.
Hydroxychloroquine
200-400 mg daily
PO
Reduces thrombotic risk in SLE-associated APS. Antithrombotic + immunomodulatory properties. Consider in all APS patients.
Obstetric APS
ASA + LMWH
ASA 81 mg + enoxaparin 40 mg daily
PO/SQ
Standard regimen for obstetric APS (recurrent pregnancy loss, preeclampsia). Start ASA preconception, add LMWH at positive pregnancy test.
Catastrophic APS (CAPS)
Triple therapy
Anticoag + steroids + PLEX or IVIG
IV
CAPS = multi-organ failure in < 1 week. ~50% mortality. Anticoagulation + methylprednisolone 1g × 3d + plasma exchange. Add rituximab or eculizumab if refractory.
⚡ Summary
Summary
Diagnose on Clinical Plus Laboratory Criteria
A clinical event, vascular thrombosis or defined pregnancy morbidity, plus a persistently positive antibody.The antibody must be positive on two occasions at least 12 weeks apart, because transient positivity after infection is common and is not APS. Testing once and treating for life is a real and consequential error.
Three Antibodies, and Triple Positivity Matters
Lupus anticoagulant, anticardiolipin, and anti-beta-2 glycoprotein I.Triple-positive patients carry the highest thrombotic risk and the highest recurrence rate, so risk stratification is by antibody profile rather than by the index event alone. Lupus anticoagulant carries the strongest association with thrombosis of the three.
DOACs Are Contraindicated
TRAPS showed rivaroxaban was inferior to warfarin with more arterial thrombotic events, particularly in triple-positive disease. Warfarin is the standard, targeting an INR of 2 to 3 for venous events, with a higher target considered after arterial or recurrent thrombosis. Switch any APS patient who arrives on a DOAC.
The Lab Paradox
Lupus anticoagulant prolongs the aPTT in vitro but causes thrombosis in vivo. The antibody interferes with the phospholipid-dependent assay, not with hemostasis. It can also make the INR unreliable in some patients, in which case chromogenic factor X or anti-Xa monitoring is needed to titrate warfarin safely.
Never Leave Them Unprotected Around Procedures
APS patients on warfarin require therapeutic LMWH bridging.The thrombotic risk during an interruption is high, and catastrophic APS is frequently triggered by surgery, infection or anticoagulation withdrawal. Plan the bridge in advance rather than simply holding the warfarin.
Manage Pregnancy Differently
Obstetric APS is treated with low-dose aspirin plus prophylactic LMWH, which substantially improves live birth rates. Warfarin is teratogenic and is stopped before or immediately on confirmation of pregnancy.Continue anticoagulation for 6 weeks postpartum, which is the highest-risk window.
Recognize Catastrophic APS
Multi-organ thrombosis developing over days, with a high mortality.Treat with triple therapy: anticoagulation, high-dose steroids, and plasma exchange or IVIG, adding rituximab or eculizumab in refractory cases. Look for and treat the trigger, most often infection, surgery or a missed anticoagulant dose.
Address the Company It Keeps
Screen for lupus and other connective tissue disease, since a large proportion of APS is secondary. Add hydroxychloroquine in lupus-associated APS, which reduces thrombotic risk. Manage conventional cardiovascular risk factors aggressively and avoid estrogen-containing contraception, which compounds an already prothrombotic state.
⚡ Management
Management
Thrombotic APS -first event: Lifelong anticoagulation with warfarin (target INR 2-3). DOACs are inferior in triple-positive APS TRAPS, 2018 -higher thrombotic events vs warfarin. DOACs may be acceptable for single/double-positive with venous events only.
Thrombotic APS -recurrent event on warfarin INR 2-3: Increase target to INR 3-4, or add low-dose ASA, or switch to LMWH.
Obstetric APS (recurrent pregnancy loss): Low-dose ASA 81 mg + prophylactic LMWH (enoxaparin 40 mg SQ daily) starting at positive pregnancy test through 6 weeks postpartum. [PROMISSE]
Catastrophic APS (CAPS): Triple therapy -anticoagulation + high-dose steroids + PLEX or IVIG. Mortality 30-50% even with treatment. Rituximab or eculizumab for refractory cases.
Asymptomatic aPL carriers: Low-dose ASA 81 mg for primary prevention (especially if lupus anticoagulant positive + additional CV risk factors). No anticoagulation.
Perioperative bridging: APS patients on warfarin require therapeutic bridging with LMWH -do NOT leave them unprotected. High thrombotic risk during interruptions.
Systemic sclerosis -fibrosis of skin and internal organs. The emergency: scleroderma renal crisis (SRC) -acute HTN + AKI + MAHA. Treatment: ACE inhibitors. Do NOT give steroids -they precipitate SRC.
C alcinosis · R aynaud's · E sophageal dysmotility · S clerodactyly · T elangiectasias
Scleroderma Renal Crisis (SRC)
SRC = acute hypertensive emergency + AKI + MAHA in a scleroderma patient. Occurs in ~10% of diffuse SSc, usually within the first 5 years. ACE inhibitors are life-saving. Steroids (especially > 15 mg prednisone/day) PRECIPITATE SRC.
Presentation: acute severe HTN (often > 180/120), rapid rise in Cr, oliguria, schistocytes on smear (MAHA), elevated LDH, thrombocytopenia (can mimic TTP)
Treatment:Captopril 6.25–12.5 mg PO q8h, titrate aggressively to normalize BP. ACEi even if Cr is rising -do NOT hold for AKI. ACEi reduces mortality from > 80% to ~25%. Continue even if patient needs dialysis (some recover renal function months later).
ARBs are NOT a substitute -evidence is only for ACE inhibitors in SRC.
Prevention: avoid steroids > 15 mg prednisone/day in diffuse SSc. Monitor BP closely in all diffuse SSc patients.
📋 On Rounds
Why do steroids precipitate scleroderma renal crisis?
The mechanism isn't fully understood, but the leading theory is that steroids cause direct endothelial injury in the renal vasculature of scleroderma patients (whose vessels are already primed by intimal fibrosis and vascular obliteration). This triggers a cascade of renin release → severe hypertension → further endothelial damage → MAHA → AKI -a vicious cycle.
Why are ACE inhibitors life-saving in scleroderma renal crisis but ARBs are not?
This is a critical distinction. ACE inhibitors block the conversion of angiotensin I → II, reducing both circulating and tissue-level angiotensin II. Before ACEi were used, scleroderma renal crisis had > 80% mortality at 1 year. With captopril, survival improved to ~60%. ARBs block the AT1 receptor but do NOT reduce angiotensin II levels -in fact, Ang II levels rise (compensatory).
What organ complications define limited vs diffuse scleroderma?
Prednisone > 15 mg/day is a risk factor for scleroderma renal crisis (SRC). The mechanism is not fully understood but likely involves steroid-induced endothelial injury in the renal vasculature → activation of the renin-angiotensin system → malignant hypertension + TMA + AKI. Anti-RNA polymerase III antibody patients are at highest risk. Rule: avoid steroids > 15 mg/day in diffuse scleroderma.
A scleroderma patient presents with sudden severe hypertension and AKI. What is this and how do you treat it?
Scleroderma renal crisis. Treat with ACE inhibitor (captopril) -titrate aggressively to normalize BP. This transformed survival from ~10% to ~65%. Do NOT use prophylactic ACEi -it may worsen outcomes. Start only when crisis occurs.
Which scleroderma antibody predicts ILD?
Anti-Scl-70 (anti-topoisomerase I) -associated with diffuse cutaneous SSc and interstitial lung disease. Anti-centromere = limited SSc (CREST) + pulmonary HTN. Anti-RNA polymerase III = renal crisis risk.
What is first-line treatment for SSc-ILD?
Mycophenolate mofetilScleroderma Lung Study II, 2016. Similar efficacy to cyclophosphamide with fewer side effects. Add nintedanibSENSCIS, 2019 if progressive despite MMF.
What screening should all scleroderma patients get annually?
PFTs with DLCO (ILD screening -FVC decline or isolated DLCO decline) and echocardiogram (PAH screening -RVSP, TR velocity). Isolated DLCO decline out of proportion to FVC suggests pulmonary hypertension rather than ILD.
📣 Sample Presentation
One-Liner
"Mrs. Kim is a 48-year-old with diffuse cutaneous systemic sclerosis (on prednisone 20 mg for ILD) presenting with acute BP 210/130, Cr rising from 1.0 to 3.8 over 3 days, and schistocytes on peripheral smear. Scleroderma renal crisis."
Key Points to Cover on Rounds
Scleroderma renal crisis -hypertension + AKI + MAHA. Risk factor: prednisone >15 mg/day. Treatment: captopril 6.25 mg PO q8h, titrated aggressively to 25 mg TID over 24h (short-acting ACEi -captopril specifically, not ARB). DO NOT hold for rising Cr -it may take weeks to recover. Prednisone tapered urgently (precipitated the crisis). BP improved 210/130→158/92 within 24h. Cr still rising (expected initially). Schistocytes → monitoring for concurrent TMA. Nephrology following -dialysis if needed (may be temporary). Plan: continue aggressive ACEi titration, trend Cr/plt/LDH daily.
🧪 Workup
Workup
ANA -positive in > 90%. Nucleolar pattern suggestive of scleroderma.
Anti-Scl-70 (anti-topoisomerase I) -associated with diffuse cutaneous SSc + ILD. ~40% of dcSSc.
Anti-centromere -associated with limited cutaneous SSc (CREST) + pulmonary HTN. ~60% of lcSSc.
Anti-RNA polymerase III -associated with scleroderma renal crisis + rapidly progressive skin. Screen these patients carefully.
PFTs with DLCO -screen at baseline and q6-12 months. FVC decline or DLCO decline > 15% = progressive ILD. Isolated DLCO decline = pulmonary HTN.
HRCT chest -ILD pattern: NSIP most common (ground-glass opacities, subpleural sparing). UIP pattern less common.
Echocardiography -annual screening for pulmonary HTN (RVSP > 40, RV dilation). Confirm with right heart catheterization if suspected.
BMP + Cr -scleroderma renal crisis: sudden severe HTN + AKI + MAHA. Medical emergency. Treat with ACE inhibitor.
UA -proteinuria, hematuria in renal crisis
Modified Rodnan Skin Score (mRSS) -extent and severity of skin thickening. Track q6-12 months.
Nailfold capillaroscopy -dilated capillary loops, hemorrhages, avascular areas. Supports diagnosis + correlates with organ involvement.
⚡ Management
Management
Raynaud's: CCBs first-line (nifedipine 30-60 mg daily or amlodipine 5-10 mg). Severe/refractory: add PDE5 inhibitor (sildenafil), IV epoprostenol, or digital sympathectomy. Avoid beta-blockers.
Skin fibrosis (dcSSc): Methotrexate for early diffuse disease [van den Hoogen]. Mycophenolate for progressive skin thickening. Tocilizumab (IL-6 inhibitor) -emerging option [focuSSced, 2020]. For severe, rapidly progressive diffuse SSc: autologous stem cell transplant SCOT, Sullivan 2018
ILD (most common cause of death in SSc): Mycophenolate (first-line) SLS II, Tashkin 2016 or nintedanib SENSCIS, Distler 2019. Cyclophosphamide as alternative SLS I, Tashkin 2006. Screen with HRCT + PFTs (FVC trend). Refer for transplant if FVC < 50% or declining rapidly.
PAH: Right heart cath to confirm. Upfront combination: ambrisentan + tadalafil [AMBITION]. Add riociguat or selexipag for inadequate response. IV epoprostenol for FC III-IV.
Scleroderma renal crisis (SRC):ACE inhibitor immediately (captopril 6.25-12.5 mg q8h, titrate aggressively). Even if creatinine rising -continue ACEi. Do NOT use ARBs (no evidence). Avoid corticosteroids ≥ 15 mg prednisone (triggers SRC). Steen & Medsger, 1990
GI: GERD → PPI (high-dose often needed). Gastroparesis → prokinetics (metoclopramide, erythromycin). GAVE (watermelon stomach) → APC ablation. Intestinal dysmotility → rotating antibiotics for SIBO.
💊 Medications
Medications
Drug
Dose
Route
Notes
ILD (Interstitial Lung Disease)
Mycophenolate mofetil
2-3g daily
PO
First-line for SSc-ILD.Scleroderma Lung Study II, 2016 -similar efficacy to cyclophosphamide with fewer side effects.
Nintedanib
150 mg BID
PO
Antifibrotic. Add-on to MMF for progressive SSc-ILD SENSCIS, 2019. Slows FVC decline. GI side effects (diarrhea).
Tocilizumab
162 mg SQ weekly
SQ
Anti-IL-6. Preserves FVC in early dcSSc with elevated inflammatory markers [focuSSced, 2020].
Raynaud's
Nifedipine ER
30-90 mg daily
PO
First-line CCB for Raynaud's. Reduces frequency/severity of attacks.
Sildenafil
20 mg TID
PO
PDE5 inhibitor for severe Raynaud's + digital ulcers. Also used for PAH.
Iloprost
0.5-2 ng/kg/min × 6h
IV
IV prostacyclin for refractory Raynaud's + digital ischemia.
Renal Crisis
ACE inhibitor (captopril)
6.25-25 mg TID, titrate aggressively
PO
Drug of choice for scleroderma renal crisis. Revolutionized survival from ~10% to ~65%. Do NOT use prophylactically -prophylactic ACEi may worsen outcomes. Start when crisis occurs.
Pulmonary Arterial Hypertension
Ambrisentan + tadalafil
10 mg + 40 mg daily
PO
Upfront combination ERA + PDE5i is standard AMBITION, 2015. Reduces hospitalization + clinical worsening.
⚡ Summary
Summary
Recognize the Triad
Acute hypertensive emergency plus acute kidney injury plus microangiopathic hemolytic anemia, in a patient with scleroderma.It occurs in about 10% of diffuse systemic sclerosis, usually within the first 5 years, which is when surveillance matters most.
ACE Inhibitors Are Life-Saving
Captopril first, because its short half-life allows rapid titration, escalated aggressively to control the blood pressure. Start it even when the creatinine is rising: this is the one situation where a climbing creatinine is not a reason to stop the ACE inhibitor, and treatment transformed the outcome from near-universal death to largely survivable.
Steroids Precipitate It
Prednisone above about 15 mg daily is a recognized trigger for scleroderma renal crisis.Avoid steroids in diffuse systemic sclerosis wherever possible, and if they are unavoidable, use the lowest dose for the shortest time with close blood pressure and creatinine monitoring.
Teach Home Blood Pressure Monitoring
A rise from the patient's own baseline is the earliest sign, and it can precede symptoms and the creatinine rise. An absolute value that looks only mildly elevated can be a crisis in a patient who normally runs low, which is why the baseline, not the threshold, is what matters.
Distinguish Limited From Diffuse
Limited (CREST): skin distal to elbows and knees plus face, anti-centromere antibody, and the feared complication is isolated pulmonary arterial hypertension, screened with annual echocardiography. Diffuse: proximal skin involvement, anti-Scl-70, and the feared complications are interstitial lung disease and renal crisis.The antibody predicts which organ will fail.
Screen the Lungs Annually in Diffuse Disease
Interstitial lung disease, usually an NSIP pattern, is a leading cause of death.PFTs with DLCO and high-resolution CT, and treat progressive disease with mycophenolate, or nintedanib or tocilizumab. Do not wait for breathlessness: by then substantial function is already lost.
Manage Raynaud and the Gut Actively
Raynaud phenomenon: cold avoidance, calcium channel blockers, and PDE5 inhibitors or prostacyclin for digital ulcers, which are painful and disabling. Esophageal dysmotility and reflux: proton pump inhibitors, elevate the head of the bed, and be aware of small bowel bacterial overgrowth causing malabsorption.
Expect Dialysis and Do Not Rush to Transplant
Many patients need renal replacement therapy during the crisis, but a substantial proportion recover enough renal function to come off dialysis over 6 to 18 months if the ACE inhibitor is continued. Wait at least 2 years before considering transplant, and do not discontinue the ACE inhibitor simply because the patient is on dialysis.
HTN emergency + AKI + MAHA. Triggered by steroids > 15 mg/day. Treatment: CAPTOPRIL (short-acting ACEi) -titrate aggressively. Don't hold for rising Cr (may take weeks to recover).
💊 Screening
ILD: HRCT + PFTs at diagnosis, then annually. PAH: echo annually. GI: PPI for GERD. Raynaud: nifedipine/amlodipine. Avoid beta-blockers (worsen Raynaud).
Crystal arthropathies -the most common inflammatory arthritis. Gout = monosodium urate (negatively birefringent needles). Pseudogout = calcium pyrophosphate (positively birefringent rhomboids). Joint aspiration is the gold standard -don't guess, tap.
🔍 Overview
Gout vs Pseudogout
Feature
Gout
Pseudogout (CPPD)
Crystal
Monosodium urate (MSU) -needle-shaped, negatively birefringent (yellow when parallel to polarizer)
Calcium pyrophosphate (CPP) -rhomboid-shaped, positively birefringent (blue when parallel)
Classic joint
1st MTP (podagra) -also ankles, knees, wrists
Knee (#1), wrists, shoulders
Demographics
Men > women (until menopause). Obesity, alcohol, purine-rich diet, CKD.
Elderly (> 65). Associated with hemochromatosis, hyperparathyroidism, hypomagnesemia, hypothyroidism.
X-ray
Erosions with overhanging edges ("rat-bite"), tophi (late)
Chondrocalcinosis (calcification of cartilage -menisci, triangular fibrocartilage of wrist)
Serum uric acid
Often ↑ but can be normal during acute flare (~40%). Do NOT rule out gout based on normal UA.
Normal
Always rule out septic arthritis first. Gout and septic arthritis can look identical (hot, swollen, painful joint with leukocytosis). Septic arthritis is joint-threatening → tap the joint. Crystal-positive fluid does NOT rule out concurrent infection -they can coexist.
💊 Management
Acute Flare Treatment
Drug
Dose
Notes
NSAIDs 1ST LINE
Indomethacin 50 mg TID × 5–7 days, or naproxen 500 mg BID
Most effective if started within 24h. Avoid in CKD, GI bleed, CHF, anticoagulation.
Colchicine (Colcrys) 1ST LINE
1.2 mg PO, then 0.6 mg 1h later (total 1.8 mg day 1). Then 0.6 mg BID until flare resolves.
Low-dose colchicine (AGREE, 2010) is as effective as high-dose with far fewer GI side effects. Best within 36h of onset. Reduce dose in CKD. Avoid with strong CYP3A4 inhibitors (clarithromycin).
Corticosteroids IF NSAIDs/COLCHICINE CI
Prednisone 30–40 mg/day × 5 days (or taper over 10–14 days). Or intra-articular triamcinolone if 1–2 joints.
Preferred in CKD, GI disease, or elderly. Intra-articular injection is ideal for monoarticular flare (after ruling out septic joint).
IL-1 inhibitor (anakinra) REFRACTORY
100 mg SC daily × 3–5 days
For patients who fail or cannot take NSAIDs, colchicine, AND steroids. Off-label but effective. anaGO, 2021
Urate-Lowering Therapy (ULT) -Chronic
🔄 Starting ULT during an acute flare CHANGED Old teaching: never start allopurinol during a flare, it will prolong the attack. Current practice (ACR 2020, conditional): it IS safe to start urate-lowering therapy during an acute flare, provided anti-inflammatory cover (colchicine 0.6 mg daily or BID, NSAID, or low-dose prednisone) is on board. Multiple RCTs show no increase in flare duration or severity. Why the change: delaying ULT by weeks creates treatment gaps and patients are lost to follow-up. Never stop ULT if the patient is already on it during a flare, abrupt urate shifts worsen the attack.
Drug
Dose
Notes
Allopurinol (Zyloprim) 1ST LINE
Start 100 mg daily (50 mg if CKD), titrate by 100 mg q2–4 weeks. Target: serum urate < 6 mg/dL.
Preferred ULT in patients with CV disease (post-MI, CAD, prior stroke), allopurinol had lower CV mortality and all-cause mortality vs febuxostat in CARES, 2018. Check HLA-B*5801 before starting in Southeast Asian, Black, and Korean patients, risk of severe hypersensitivity (SJS/TEN/DRESS). Start low, go slow.
Febuxostat (Uloric) 2ND LINE
40–80 mg daily
AVOID in patients with CV disease (post-MI, CAD, prior stroke).CARES, 2018: febuxostat had higher CV mortality (HR 1.34) and all-cause mortality (HR 1.22) vs allopurinol, leading to an FDA black-box warning. Reserve for: patients who fail allopurinol, are HLA-B*5801 positive, or have severe allopurinol intolerance.
Indications for ULT (ACR 2020):Strong recommendation: ≥ 2 flares/year, ≥ 1 subcutaneous tophus, or radiographic damage from gout. Conditional recommendation (start ULT after even 1 flare if): CKD stage ≥ 3, serum urate > 9 mg/dL, or urolithiasis (urate stones). Target serum urate < 6 mg/dL (< 5 if tophi). Why titrate to a number, not symptom relief: below the urate saturation point (~6.8 mg/dL) crystals dissolve and tophi shrink. Treating to target is what prevents recurrent flares and joint erosion; treating only until the patient feels better leaves crystals in place and the next flare is coming.
Joint aspiration -gold standard. Negatively birefringent, needle-shaped monosodium urate crystals under polarized light. Yellow when parallel to compensator.
Synovial fluid WBC -2,000-50,000 (inflammatory range). ALWAYS send culture + gram stain -gout and septic arthritis can coexist (up to 5% of gout flares).
Serum uric acid -can be NORMAL during acute flare (don't use to diagnose). Check between flares for ULT target. Flare threshold usually > 6.8 mg/dL (supersaturation point).
BMP + Cr -renal function determines medication choice (colchicine dose, allopurinol starting dose). CKD is both a cause and consequence of hyperuricemia.
CBC -leukocytosis during flare (mimics infection)
HLA-B*5801 -BEFORE allopurinol in Southeast Asian, African American, Hawaiian/Pacific Islander patients. Strong predictor of DRESS/SJS. If positive → use febuxostat instead.
24h urine uric acid -uric acid overproducer (> 800 mg/day) vs underexcretor. Guides ULT choice (xanthine oxidase inhibitor vs uricosuric).
X-ray -acute: soft tissue swelling only. Chronic: "rat-bite" erosions with overhanging edges, tophi. DECT: urate crystal deposition (research, not routine).
💊 Medications
Medications
Drug
Dose
Route
Notes
Acute Flare Treatment
Colchicine
1.2 mg → 0.6 mg at 1h (day 1), then 0.6 mg BID
PO
Low-dose regimen AGREE, 2010 -equally effective, far fewer GI side effects. Reduce dose if CrCl < 30 (0.3 mg BID). Onset within 24h.
Indomethacin
50 mg TID × 3 days, then taper
PO
NSAID -fast acting. Avoid in CKD, GI bleed, HF, anticoagulation. Naproxen 500 BID is alternative.
Prednisone
30-40 mg daily × 5 days
PO
If NSAIDs + colchicine contraindicated. Equally effective. No taper for 5-day course. Best for polyarticular flare.
Intra-articular triamcinolone
10-40 mg per joint
IA
Monoarticular flare -fast relief. Must rule out septic joint first (culture synovial fluid).
Anakinra
100 mg SQ × 3-5 days
SQ
IL-1 receptor antagonist. For refractory flares when ALL of the above are contraindicated (CKD + CHF + anticoag + infection).
Urate-Lowering Therapy (ULT) -Start ≥ 2 weeks after flare resolves
Allopurinol
Start 100 mg daily (50 mg if CKD), titrate by 100 mg q2-4 weeks
PO
Xanthine oxidase inhibitor. Target UA < 6 mg/dL. Max 800 mg. Check HLA-B*5801 first in at-risk populations. Titrate slowly -faster titration does NOT cause more flares. Allopurinol Dose-Escalation Study, 2017
Febuxostat
40-80 mg daily
PO
XOI alternative if allopurinol intolerant or HLA-B*5801+. More potent per mg. FDA CV warning but FAST, 2020 showed non-inferiority to allopurinol.
Probenecid
250 mg BID → 500 mg BID
PO
Uricosuric. Only if underexcretor. Contraindicated if CrCl < 50 or nephrolithiasis.
Pegloticase
8 mg IV q2 weeks
IV
Recombinant uricase. Refractory tophaceous gout only. Must premedicate. Check UA before each infusion -if > 6, discontinue (loss of response → anaphylaxis risk).
Flare prophylaxis when starting ULT: colchicine 0.6 mg daily × 3-6 months. Starting ULT mobilizes urate crystals from deposits → paradoxical flares. Do NOT stop ULT during a flare -it does not worsen flares and stopping/starting destabilizes urate levels.
📋 On Rounds
Why can serum uric acid be normal during an acute gout flare?
During an acute inflammatory response, IL-6 increases renal urate excretion via uricosuric effects and redistributes urate from plasma into tissues. Additionally, the acute phase response and volume shifts during inflammation dilute serum urate. Up to 40% of acute gout flares have a normal serum uric acid. This is why a normal UA does NOT rule out gout -you need joint aspiration with polarized microscopy (negatively birefringent crystals)
A patient with gout is already on allopurinol. Should you stop it during an acute flare?
NO -do NOT stop allopurinol during an acute flare. This is one of the most commonly made errors. Stopping or starting ULT (urate-lowering therapy) during a flare causes uric acid fluctuations that can prolong and worsen the flare. If the patient is already on allopurinol, continue it at the same dose and treat the flare with NSAIDs, colchicine, or steroids. If ULT hasn't been started yet, wait until the flare resolves (2–4 weeks)
What is the treat-to-target approach for uric acid, and what level do you aim for?
Target serum uric acid < 6 mg/dL (or < 5 mg/dL if tophi present). The monosodium urate saturation point is ~6.8 mg/dL -keeping UA below 6 ensures crystals dissolve over time and prevents new deposition. Treat-to-target protocol: Start allopurinol low (100 mg daily, or 50 mg if CKD) → increase by 100 mg every 2-4 weeks → check UA level → keep titrating until UA < 6. Most patients need 300-600 mg daily (not the old default of 300 mg).
What is the role of IL-1 inhibitors in gout?
Anakinra (IL-1 receptor antagonist) is used for acute gout flares when NSAIDs, colchicine, AND steroids are all contraindicated or failed -typically in patients with CKD + HF + active infection (can't use NSAIDs, colchicine, or steroids safely). Dose: 100 mg SQ daily × 3 days. Works by blocking IL-1β, which is the key cytokine released when NLRP3 inflammasome is activated by MSU crystals.
A patient has an acute gout flare. Should you start allopurinol now?
Current guidelines say you CAN start ULT during a flare [ACR 2020] -it does not worsen or prolong the flare. But always add flare prophylaxis (colchicine). Never STOP ULT during a flare -stopping/restarting destabilizes urate levels.
Why do you check HLA-B*5801 before starting allopurinol?
HLA-B*5801 is a strong predictor of severe allopurinol hypersensitivity (DRESS/SJS/TEN) -fatality rate ~25%. Prevalence: 6-8% in Southeast Asian, 3.5% in African American. If positive → use febuxostat instead.
What is the serum urate target for gout ULT?
< 6 mg/dL (below the supersaturation point of 6.8 mg/dL). For severe tophaceous gout, target < 5. It takes 6-12 months of sustained target to dissolve tissue urate deposits.
Clinical Examples
📋 Case 1, Acute Gout in CKD
Patient: 68-year-old man with CKD stage 4 (GFR 22), HTN, and no prior gout history presenting with acute right knee swelling, erythema, and severe pain × 1 day. WBC 14,000. Temp 38.1°C.
Key findings: Arthrocentesis: WBC 38,000, negatively birefringent needle-shaped crystals. Gram stain negative, culture pending. Serum uric acid 6.4 (normal, does not rule out gout). Cr 3.8 at baseline.
Management:
NSAIDs and high-dose colchicine both contraindicated (CKD 4)
Prednisone 30 mg PO daily × 5 days (preferred in CKD when infection excluded)
Intra-articular triamcinolone 40 mg, ideal for monoarticular flare after ruling out septic joint
Continue culture follow-up, gout and septic arthritis can coexist (5% of cases)
Teaching point: In CKD, steroids (PO or intra-articular) are the safest option. Normal uric acid during a flare occurs in ~40% of cases due to IL-6-mediated uricosuria, never use it to rule out gout.
📋 Case 2, ULT Initiation with Mobilization Flare
Patient: 55-year-old man with 4 gout flares in the past year, tophi on bilateral elbows. UA 9.2 mg/dL between flares. HLA-B*5801 negative. Started allopurinol 100 mg daily 3 weeks ago with colchicine 0.6 mg daily prophylaxis. Now presents with acute left 1st MTP flare.
Key findings: This is a mobilization flare, expected when starting ULT as tissue urate deposits dissolve and crystals are released into joints. UA trending down to 7.4 (not yet at target).
Management:
Do NOT stop allopurinol, stopping/restarting destabilizes urate levels and worsens outcomes
Treat the acute flare: colchicine 1.2 mg then 0.6 mg in 1h, then resume 0.6 mg BID AGREE, 2010
Continue uptitrating allopurinol by 100 mg q2-4 weeks → target UA < 5 mg/dL (tophi present)
Continue colchicine prophylaxis × 6 months after reaching target
Teaching point: Mobilization flares are expected and do NOT mean ULT has failed, they mean urate is being cleared. Continue ULT, treat the flare, and reassure the patient.
📋 Case 3, Pseudogout Mimicking Septic Joint
Patient: 78-year-old woman with hypothyroidism presenting with acute right wrist swelling, warmth, and fever (38.5°C) × 2 days after a hospitalization for pneumonia. WBC 16,000. X-ray shows chondrocalcinosis of the triangular fibrocartilage.
Key findings: Arthrocentesis: WBC 45,000, positively birefringent rhomboid-shaped crystals (calcium pyrophosphate). Gram stain negative. No growth at 48h.
Management:
Acute CPPD flare (pseudogout), triggered by acute illness/hospitalization
Treatment same as gout flare: NSAIDs, colchicine, or steroids
Given age and recent pneumonia → prednisone 25 mg × 5 days
Check for metabolic associations: hypothyroidism (already known), hemochromatosis (ferritin, iron saturation), hyperparathyroidism (calcium, PTH), hypomagnesemia
Teaching point: Pseudogout is commonly triggered by acute medical illness or surgery. Unlike gout, there is no urate-lowering equivalent, treatment is limited to flare management. Always check for associated metabolic conditions, especially in patients under 60.
📣 Sample Presentation
One-Liner
"Mr. Thompson is a 62-year-old with CKD3 presenting with acute right first MTP joint erythema, swelling, and exquisite tenderness × 2 days. Joint aspiration shows negatively birefringent needle-shaped crystals. WBC 42,000 in synovial fluid. Acute gout."
Key Points to Cover on Rounds
Acute gout confirmed by crystal analysis. Septic joint ruled out (culture pending, but crystals identified -can coexist, treat empirically if concern). Treatment: colchicine 1.2 mg then 0.6 mg 1h later, then 0.6 mg BID (low-dose per AGREE, 2010 -less GI toxicity than traditional high-dose). NSAIDs avoided (CKD3). Uric acid level 7.8 (can be normal during flare). Already on allopurinol 200 mg -continued (don't stop during flare). Plan: after flare resolves → uptitrate allopurinol to target uric acid <6, continue colchicine 0.6 mg daily × 6 months as prophylaxis. Check HLA-B*5801 if not previously done.
Monitoring
Serum uric acid q2-4 weeks while titrating ULT -target < 6 mg/dL (or < 5 if tophi present). Most common error: starting at full dose. Always start low, go slow.
Cr + LFTs q3-6 months on allopurinol/febuxostat -rare hepatotoxicity, dose-adjust for CKD
CBC if on colchicine long-term (rare bone marrow suppression, especially with CKD or statin interaction)
Flare frequency -should decrease after 6-12 months of ULT at target. Early ↑ in flares is expected when starting ULT (crystal mobilization) -this is why prophylaxis is essential
Colchicine prophylaxis × 3-6 months when starting or titrating ULT (0.6 mg daily or BID). Prevents mobilization flares. Continue until urate at target for ≥ 3-6 months with no flares.
Tophi assessment -should shrink over 12-24 months on ULT. If persistent → urate not at target
Joint imaging -X-ray at baseline for erosions. Dual-energy CT if diagnostic uncertainty (research tool, not routine follow-up)
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
⚡ Summary
Summary
Tap the Joint
Joint aspiration is the gold standard; do not diagnose by pattern recognition alone.Gout: negatively birefringent needle-shaped monosodium urate crystals.Pseudogout: positively birefringent rhomboid calcium pyrophosphate crystals. Send cell count, Gram stain and culture on the same sample.
Rule Out Septic Arthritis First
Gout and septic arthritis look identical: a hot, swollen, painful joint with leukocytosis and fever.Crystals in the fluid do not exclude infection, since the two coexist, so a crystal-positive aspirate with a high cell count and a convincing clinical picture still needs culture and empiric cover. Septic arthritis is joint-threatening within 24 to 48 h.
Do Not Use the Uric Acid to Diagnose a Flare
Serum urate is often normal or low during an acute attack, because urate deposits into the joint as the flare develops. A normal level does not exclude gout and a high level does not diagnose it, since most hyperuricemic people never get gout. Check it 2 weeks after the flare settles to establish a baseline for treatment.
Treat the Flare With Any of Three, Chosen by Comorbidity
NSAIDs if renal function, GI history and cardiovascular risk allow. Colchicine, low-dose (1.2 mg then 0.6 mg an hour later), which is as effective as high-dose with far less diarrhea, and dose-reduced for renal impairment and interactions. Steroids, oral, intra-articular or intramuscular, and the safest choice in chronic kidney disease, heart failure and anticoagulation. Intra-articular injection is ideal for a single joint once infection is excluded.
Start Treatment Early and to a Target
The earlier the flare is treated the faster it settles, so patients with recurrent gout should have a home supply and a written plan rather than waiting for an appointment. Treat until the flare resolves, then stop, rather than continuing indefinitely.
You Can Now Start Urate-Lowering Therapy During a Flare
Old teaching was to wait; ACR 2020 says it is safe to start during an acute attack provided effective anti-inflammatory cover is running. Starting during the admission markedly improves the chance the patient actually takes it, since deferring to an outpatient visit means many never start.
Treat to a Urate Target, With Prophylaxis
Indications: two or more flares a year, tophi, radiographic damage, or urate nephrolithiasis.Allopurinol first line, started at 100 mg or less and titrated to a urate below 6 mg/dL, below 5 with tophi. Give colchicine or an NSAID as flare prophylaxis for 3 to 6 months while titrating, because mobilizing urate provokes attacks and that is why patients stop the drug.
Know the Allopurinol and Febuxostat Cautions
Test HLA-B*5801 before allopurinol in Han Chinese, Thai, Korean and other high-prevalence groups, because of severe cutaneous adverse reactions. Febuxostat carries a cardiovascular mortality signal (CARES) and is second line. Pseudogout is treated the same way acutely but has no urate-lowering equivalent: look instead for hemochromatosis, hyperparathyroidism, hypomagnesemia and hypophosphatasia in younger patients.
Stopping ULT during acute flare (don't stop -continue and add anti-inflammatory)
Starting ULT without flare prophylaxis (colchicine × 3-6 months)
Not checking HLA-B*5801 in at-risk populations
High-dose colchicine (use low-dose -same efficacy, less GI toxicity)
EmergentRheumatology
SLE Flare
Lupus is the great mimicker. Flares can involve any organ. The most dangerous: lupus nephritis (Class III/IV/V), cerebral lupus, catastrophic APS, and diffuse alveolar hemorrhage. Labs: ↓ complement (C3/C4), ↑ anti-dsDNA = active disease.
↑ ESR with normal CRP -classic lupus pattern (CRP usually only rises in serositis or infection, not lupus flares). If CRP is high → think infection.
Worsening cytopenias -active disease. But also consider medication side effects.
ESR ↑ + CRP normal = lupus flare. ESR ↑ + CRP ↑ = infection until proven otherwise. This distinction is clinically useful for differentiating flare vs infection in SLE patients (who are immunosuppressed and infection-prone).
💊 Management
Treatment by Severity
Severity
Treatment
All patients (baseline)
Hydroxychloroquine (Plaquenil) 200–400 mg dailyCORNERSTONE -reduces flares, organ damage, thrombosis, and mortality. Never stop. Annual eye exam for retinal toxicity.
Pulse methylprednisolone 1g IV daily × 3 days → prednisone 1 mg/kg. Then: mycophenolate (preferred for nephritis induction -ALMS, 2009) or cyclophosphamide (Euro-Lupus low-dose protocol for severe nephritis). Belimumab (anti-BAFF) for add-on in active lupus nephritis BLISS-LN, 2020. Voclosporin (calcineurin inhibitor) added to MMF for nephritis AURORA, 2021.
📋 Clinical Example -Lupus Flare Assessment & Management
Patient: 28F with known SLE, presents with fatigue, joint pain, malar rash, oral ulcers, Cr rising from 0.8 → 1.6 over 2 weeks.
Flare workup:
Labs: CBC (cytopenias?), BMP (renal), UA with microscopy (RBC casts = lupus nephritis), protein/creatinine ratio, complement C3/C4 (low = active disease), anti-dsDNA (rising titer = flare), ESR/CRP.
UA: 2+ protein, 25 RBCs, RBC casts → active lupus nephritis. Protein/Cr ratio 2.8 (>0.5 = significant proteinuria).
Key: Hydroxychloroquine is the ONE drug every SLE patient should be on. Reduces flares, organ damage, and mortality.
📋 On Rounds
How do you distinguish lupus flare from infection in an immunosuppressed SLE patient?
This is one of the hardest clinical questions in rheumatology. Key clues: (1) CRP: low/normal in flare, elevated in infection. (2) Complement (C3/C4): drops in flare, normal or rises (acute phase) in infection. (3) Procalcitonin: elevated in bacterial infection, usually normal in flare (though not perfect). (4) Anti-dsDNA: rising in flare, stable in infection
Why is CRP typically normal in a lupus flare but elevated in infection?
In most autoimmune flares, CRP remains low or normal because lupus inflammation is driven by type I interferons, which actually suppress hepatic CRP production. In contrast, bacterial infection drives IL-6 release → potent CRP stimulation in the liver → CRP rises markedly. This makes CRP a useful discriminator: CRP < 5 + low C3/C4 + rising anti-dsDNA = flare.CRP > 50 + normal complements = infection.
Why should hydroxychloroquine never be stopped in SLE?
HCQ is the only SLE medication proven to reduce mortality -and the effect is dose-independent (even low doses help). Benefits: (1) Reduces flare frequency by 50-60%, (2) Reduces thrombosis risk (important in APS overlap), (3) Improves lipid profiles, (4) Reduces renal damage progression, (5) Safe in pregnancy (one of few SLE drugs that is). Stopping HCQ increases flare risk by 2.5× within 6 months. Even during remission, continue HCQ.
What are the indications for renal biopsy in lupus nephritis?
Biopsy is indicated whenever there is evidence of renal involvement in SLE -it determines the ISN/RPS class (I-VI) which directly guides treatment. Indications: (1) Proteinuria > 500 mg/day (UPCR > 0.5), (2) Active urine sediment (RBC casts, dysmorphic RBCs), (3) Unexplained rising creatinine, (4) Combination of proteinuria + hematuria even if individually below threshold. Why biopsy matters: Class I/II (minimal/mesangial)
Clinical Examples
📋 Case 1, Lupus Nephritis Class IV
Patient: 24-year-old woman with known SLE presenting with bilateral LE edema, foamy urine × 2 weeks, and fatigue. BP 148/92.
Key findings: UPCR 3.8 (nephrotic range), UA: 25 RBCs/hpf with RBC casts. C3 42 (low), C4 6 (low). Anti-dsDNA 1:640 (rising). CRP 1.8 (low). Renal biopsy: Class IV with crescents.
Teaching point: Cannot predict nephritis class clinically, biopsy is mandatory. Class IV is most common and aggressive. Low CRP + low complements = classic SLE flare pattern.
📋 Case 2, SLE Flare vs Infection
Patient: 32-year-old woman with SLE on mycophenolate and prednisone 10 mg, presenting with fever 39.1°C, fatigue, worsening joint pain × 3 days.
Infection, not flare, high CRP, normal complements, stable dsDNA, elevated procalcitonin
Treat UTI per sensitivities. Hold mycophenolate during infection.
Do NOT increase steroids. Resume MMF once cleared.
Teaching point: CRP low + C3/C4 low + dsDNA rising = flare. CRP high + C3/C4 normal + procalcitonin elevated = infection. When uncertain, cover both.
📋 Case 3, SLE in Pregnancy
Patient: 29-year-old woman with SLE (class III nephritis in remission × 18 months) on HCQ and azathioprine, now 8 weeks pregnant. Anti-Ro/SSA positive.
"Ms. Johnson is a 28-year-old with SLE presenting with facial rash, pleuritic chest pain, and UA showing 2+ protein and 15 RBCs/hpf. Anti-dsDNA elevated, C3/C4 low. CRP 2.4 (low). Consistent with lupus flare with possible nephritis."
Key Points to Cover on Rounds
SLE flare -active serology (rising anti-dsDNA, falling C3/C4). CRP low (supports flare over infection). Organ involvement: skin (malar rash), serositis (pleuritic chest pain -CXR: small left pleural effusion), renal (proteinuria + hematuria → nephritis?). Urine protein/Cr ratio sent -UPCR 2.4 (nephrotic range). Nephrology consulted for renal biopsy (needed for class determination → guides treatment). Hydroxychloroquine continued (never stop -reduces flares, thrombosis, mortality). Prednisone 0.5 mg/kg started pending biopsy. If class III/IV → mycophenolate or cyclophosphamide induction. Plan: renal biopsy this week, continue HCQ + steroids, check for infection before immunosuppression.
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
🧪 Workup
Workup -Systemic Lupus Erythematosus
ANA is the gate, not the diagnosis. It is highly sensitive and poorly specific, so it is useful to rule lupus out and nearly useless alone to rule it in. A negative ANA makes SLE very unlikely; a positive ANA in an otherwise well patient usually means nothing. Test only when there is a clinical reason.
Test
What it tells you
ANA
Screening test. Positive in nearly all SLE, but also in healthy people, other autoimmune disease, and with age. Report the titre and pattern.
Anti-dsDNA
Specific for SLE and tracks disease activity, particularly lupus nephritis. Useful to follow serially once the diagnosis is made.
Anti-Smith
The most specific antibody for SLE, but present in only a minority. A positive result largely settles the diagnosis; a negative one excludes nothing.
C3 and C4
Fall during active disease as complement is consumed. A falling complement with a rising dsDNA is the classic serologic signature of a flare, especially renal.
Urinalysis with sediment, plus urine protein:creatinine
The single most important test at every visit. Lupus nephritis is often silent until it is advanced, so proteinuria, hematuria and cellular casts are actively looked for rather than waited for.
CBC, creatinine, LFTs
Cytopenias are diagnostic criteria in their own right: hemolytic anemia, leukopenia, lymphopenia and thrombocytopenia. Creatinine tracks renal involvement.
Antiphospholipid antibodies
Lupus anticoagulant, anticardiolipin and anti-beta-2-glycoprotein I. Check at diagnosis, because they change thrombotic and pregnancy risk and therefore management.
Anti-Ro and anti-La
Relevant in pregnancy: they cross the placenta and cause neonatal lupus and congenital heart block, which changes fetal monitoring.
Renal biopsy
Indicated for significant proteinuria or an active sediment. The ISN/RPS class dictates whether the patient needs induction immunosuppression, so the biopsy drives treatment rather than confirming a hunch.
Before starting hydroxychloroquine, arrange a baseline eye examination, then annual retinal screening from year five, or sooner with renal impairment or high dosing. Retinopathy is irreversible, and screening exists to catch it before vision is lost.
💊 Medications
Key Medications -Systemic Lupus Erythematosus
Drug
Dose
Role
Watch for
Hydroxychloroquine EVERYONE
5 mg/kg actual body weight per day, usually 200 to 400 mg
Background therapy for essentially every patient with SLE. Reduces flares, organ damage and mortality, and improves pregnancy outcomes.
Retinal toxicity is the dose-limiting harm, hence the weight-based cap and annual screening from year five. Do not stop it in pregnancy.
Glucocorticoids
Dose to severity; pulse methylprednisolone for organ-threatening disease
Fast control while a slower agent takes effect.
The goal is always to get off them. Cumulative steroid exposure, not lupus itself, causes much of the long-term damage. Taper deliberately and add a steroid-sparing agent early.
Mycophenolate mofetil
2 to 3 g daily for induction
Lupus nephritis induction and maintenance, and useful in non-renal disease.
Teratogenic. Requires reliable contraception and a switch to azathioprine before a planned pregnancy.
Cyclophosphamide
Low-dose Euro-Lupus or NIH regimens
Severe organ-threatening disease: proliferative nephritis, CNS lupus, alveolar hemorrhage.
Gonadal toxicity, infection, hemorrhagic cystitis and later malignancy. Discuss fertility preservation before starting.
Belimumab
IV or subcutaneous
Active SLE and lupus nephritis, added to standard therapy. Anti-BLyS monoclonal.
Infection risk. Slow onset, so it is an add-on for persistent activity rather than a rescue drug.
Anifrolumab
IV every 4 weeks
Type I interferon receptor blocker for moderate to severe SLE, particularly skin and joint disease.
Not approved for lupus nephritis or CNS lupus, which is the distinction most often got wrong. Increased herpes zoster risk.
Voclosporin
Oral, with background therapy
Calcineurin inhibitor approved specifically for active lupus nephritis in combination with mycophenolate and steroids.
Monitor blood pressure and eGFR; calcineurin inhibitors are nephrotoxic, which is a particular consideration in a nephritis population.
⚡ Summary
Summary
ANA Is the Gate, Not the Diagnosis
Highly sensitive and poorly specific, so it rules lupus out and is nearly useless alone to rule it in.A negative ANA makes SLE very unlikely; a positive ANA in an otherwise well patient usually means nothing.Anti-dsDNA and anti-Smith are the specific antibodies, and anti-dsDNA also tracks disease activity.
Track Flares With Complement and dsDNA
Falling C3 and C4 with rising anti-dsDNA indicates active disease, because complement is consumed by immune complexes. Trend them over time rather than reading a single set.
The ESR-CRP Split Separates Flare From Infection
Raised ESR with a normal CRP suggests a lupus flare. Raised ESR with a raised CRP is infection until proven otherwise.This distinction is genuinely useful in a population that is immunosuppressed, infection-prone, and in whom the two present almost identically. Serositis is the main lupus exception that does raise CRP.
Hydroxychloroquine for Everyone
It reduces flares, organ damage and mortality, and improves survival in lupus nephritis.Continue it through pregnancy and through flares.Annual retinal screening for the dose- and duration-related retinopathy, keeping the dose at or below 5 mg/kg of actual body weight.
Know the Dangerous Manifestations
Lupus nephritis (classes III, IV and V), cerebral lupus, catastrophic antiphospholipid syndrome and diffuse alveolar hemorrhage.These are the ones that kill, and they are treated with high-dose steroids plus an induction agent rather than with escalating outpatient therapy.
Biopsy the Kidney Rather Than Guessing
Proteinuria, an active sediment or a rising creatinine means a renal biopsy, because the class determines the treatment and cannot be predicted from the serology. Induction with mycophenolate or low-dose cyclophosphamide plus steroids, increasingly with belimumab or voclosporin added, then maintenance. Class IV carries the worst renal prognosis.
Minimize the Steroids Deliberately
Most long-term damage in lupus comes from corticosteroids rather than from the disease: osteoporosis, avascular necrosis, diabetes, cataracts, infection and cardiovascular disease. Use steroid-sparing agents early and taper with intent, rather than leaving patients on a maintenance dose indefinitely because it is easier.
Manage the Long-Term Risks
Accelerated atherosclerosis makes cardiovascular disease a leading cause of death, so treat conventional risk factors aggressively. Screen for antiphospholipid antibodies, which change anticoagulation and pregnancy management. Plan pregnancy during quiescent disease, and check anti-Ro and anti-La, which cause neonatal lupus and congenital heart block. Vaccinate before immunosuppression, and add PJP prophylaxis with high-dose steroids plus a cytotoxic agent.
Inflammation of blood vessel walls → ischemia and organ damage. Classified by vessel size. The ANCA-associated vasculitides (GPA, MPA, EGPA) are the ones you'll see on the wards. Pulmonary-renal syndrome = treat immediately.
Steroids (often sufficient for mild). Mepolizumab (anti-IL5) MIRRA, 2017. Cyclophosphamide if organ-threatening.
Medium vessel
PAN (Polyarteritis Nodosa)
ANCA-negative. Microaneurysms on angiography. Skin (livedo, nodules, ulcers), renal (HTN, infarction -but NOT glomerulonephritis), GI (mesenteric ischemia), neuropathy. Associated with HBV.
Negative
Steroids + cyclophosphamide. Treat HBV if associated.
Large vessel
Giant Cell Arteritis (GCA)
Age > 50. Temporal headache, jaw claudication, scalp tenderness, vision loss (anterior ischemic optic neuropathy). ESR often > 100.
Negative
Start steroids BEFORE biopsy (don't wait -vision loss is irreversible). Prednisone 40–60 mg/day. Tocilizumab for steroid-sparing GiACTA, 2017.
Takayasu arteritis
Young women (< 40). Aorta + branches → limb claudication, BP discrepancy, absent pulses, bruits. "Pulseless disease."
Negative
Steroids + methotrexate/tocilizumab.
Pulmonary-Renal Syndrome
DAH (hemoptysis + bilateral infiltrates + dropping Hgb) + RPGN (rising Cr + active sediment) = pulmonary-renal syndrome. This is a medical emergency. Differential: GPA, MPA, anti-GBM (Goodpasture's), SLE. Send ANCA, anti-GBM, ANA, complement. Start pulse methylprednisolone 1g IV × 3 days + cyclophosphamide or rituximab + plasmapheresis (especially if anti-GBM positive). Do NOT wait for biopsy to start treatment.
🧪 Workup
Workup
ANCA -c-ANCA/PR3 (GPA/Wegener's), p-ANCA/MPO (MPA, EGPA). Send BOTH ELISA (PR3, MPO) AND IFA (c-ANCA, p-ANCA).
CBC, BMP, LFTs, ESR, CRP -baseline organ function + inflammatory markers
UA with microscopy -dysmorphic RBCs, RBC casts = glomerulonephritis (RPGN). This is an emergency -needs urgent renal biopsy.
Complement levels (C3, C4) -low in complement-mediated vasculitis (cryoglobulinemic, anti-GBM, SLE). Normal in ANCA vasculitis.
Cryoglobulins + HCV -HCV-associated cryoglobulinemic vasculitis (type II mixed)
Anti-GBM antibodies -Goodpasture syndrome (pulmonary-renal syndrome with linear IgG on biopsy)
Eosinophil count -markedly elevated in EGPA (eosinophilic granulomatosis with polyangiitis / Churg-Strauss)
⚡ Management
Treatment -ANCA-Associated Vasculitis
Phase
Regimen
Details
Induction
Pulse methylpred 1g IV × 3d → pred 1 mg/kg taper + Rituximab (Rituxan) 375 mg/m² × 4 wks
Rituximab preferred over cyclophosphamide RAVE, 2010. Especially for PR3+/relapsing.
Alternative
Cyclophosphamide IV 15 mg/kg q2–4 wks
If rituximab unavailable. Limit cumulative dose (bladder CA risk). Mesna for cystitis prevention.
Severe renal/DAH
Add plasmapheresis
PLEX for Cr > 5.7 or DAH requiring ventilation.
Maintenance
Rituximab (Rituxan) 500 mg q6 months or azathioprine (Imuran)
Maintain ≥ 2 years. PR3+ = longer maintenance (higher relapse).
💊 Medications
Medications
Drug
Dose
Route
Notes
ANCA-Associated Vasculitis -Induction
Rituximab
375 mg/m² weekly × 4 or 1000 mg × 2
IV
First-line induction (equal to cyclophosphamide).RAVE, 2010. Preferred in relapsing disease. Fewer side effects than CYC. Screen HBV.
Cyclophosphamide
15 mg/kg IV q2 weeks × 3 then q3 weeks
IV
Alternative induction. Effective but more toxicity (bladder cancer, infertility, myelosuppression). Mesna for bladder protection. Limit cumulative dose.
Methylprednisolone
500-1000 mg IV × 3 days
IV
Pulse steroids with induction. Then prednisone 1 mg/kg taper over 3-6 months. [PEXIVAS: reduced-dose glucocorticoid non-inferior, 2020]
Avacopan
30 mg BID
PO
C5a receptor inhibitor -steroid-sparing.ADVOCATE, 2021. Can replace prednisone during induction (add to RTX or CYC). Superior sustained remission at 52 weeks.
Maintenance
Rituximab
500 mg q6 months × 2-4 years
IV
Preferred maintenance.MAINRITSAN, 2014 -superior to azathioprine. Duration: minimum 2 years, possibly longer for PR3+.
Azathioprine
2 mg/kg/day
PO
Alternative maintenance. Check TPMT. Less effective than rituximab for relapse prevention.
Giant Cell Arteritis (GCA)
Prednisone
40-60 mg daily
PO
Start IMMEDIATELY if clinical suspicion -do NOT wait for biopsy. Taper over 12-24 months. Visual loss = methylprednisolone 1g IV × 3d.
Tocilizumab
162 mg SQ weekly
SQ
Steroid-sparing for GCA.GiACTA, 2017. Sustained remission with 26-week taper vs 52-week steroid-only taper. Now first-line adjunct.
⚡ Summary
Summary
Classify by Vessel Size
Large vessel: giant cell arteritis, Takayasu. Medium: polyarteritis nodosa, Kawasaki. Small: the ANCA-associated vasculitides plus immune-complex disease.Vessel size predicts the clinical syndrome, which is why classification is the first step rather than an academic exercise.
Pulmonary-Renal Syndrome Is an Emergency
Diffuse alveolar hemorrhage (hemoptysis, bilateral infiltrates, a falling hemoglobin) plus rapidly progressive glomerulonephritis (rising creatinine, active sediment).Send ANCA, anti-GBM, ANA and complement immediately, and treat before they return. Differential: GPA, MPA, anti-GBM disease and lupus. Hemoptysis may be absent even with significant alveolar hemorrhage.
Let the ANCA Pattern Point to the Disease
c-ANCA / PR3: granulomatosis with polyangiitis, with upper airway disease (sinusitis, saddle-nose deformity, subglottic stenosis), lung nodules and cavities, and glomerulonephritis. p-ANCA / MPO: microscopic polyangiitis, renal and pulmonary without granulomas or upper airway disease. EGPA: asthma, eosinophilia and neuropathy, ANCA-positive in only about 40%.
A Negative ANCA Does Not Exclude It
Roughly 10% of ANCA-associated vasculitis is ANCA-negative, and EGPA is negative more often than not. Biopsy remains the gold standard, from kidney, lung, skin or nerve depending on the involved organ, and it should not be deferred because a serology was negative.
Induction Is Steroids Plus a Second Agent
Pulse methylprednisolone plus either rituximab or cyclophosphamide.RAVE showed rituximab is non-inferior to cyclophosphamide for induction and superior for relapsing disease, and it avoids infertility and bladder toxicity. Add plasma exchange for severe alveolar hemorrhage or a very high creatinine, and for anti-GBM disease, where it is central.
Maintain, Because Relapse Is the Rule
Rituximab is superior to azathioprine for maintenance (MAINRITSAN), continued for at least 18 to 24 months. Stopping immunosuppression too early is the commonest cause of relapse, and each relapse causes further irreversible organ damage.
Give the Prophylaxis That Goes With the Immunosuppression
PJP prophylaxis with TMP-SMX for anyone on high-dose steroids plus a cytotoxic or B-cell depleting agent.Bone protection, glucose monitoring and vaccination before starting where possible.Screen hepatitis B before rituximab, which reactivates it. Mesna and hydration with cyclophosphamide to prevent hemorrhagic cystitis.
Know the Named Mimics and Look Beyond the Kidney
Mononeuritis multiplex, palpable purpura, episcleritis, scleritis and sinus disease are the findings that point to vasculitis when the renal picture is ambiguous. Exclude infection and drug-induced ANCA vasculitis (hydralazine, propylthiouracil, levamisole-adulterated cocaine, minocycline) before committing to long-term immunosuppression, since the treatment there is stopping the drug. Endocarditis mimics vasculitis closely, and immunosuppressing it is catastrophic.
📋 On Rounds
Why start steroids before temporal artery biopsy in suspected GCA?
Vision loss from GCA is irreversible. Anterior ischemic optic neuropathy (AION) from inflammation of the ophthalmic or posterior ciliary arteries can cause sudden permanent blindness -and once one eye is affected, the other is at high risk within days. The biopsy remains diagnostic even 2–6 weeks after starting steroids (the inflammatory infiltrate takes weeks to resolve).
What's the difference between c-ANCA/PR3 and p-ANCA/MPO and why does it matter?
c-ANCA (anti-PR3) is associated with GPA (granulomatosis with polyangiitis, formerly Wegener's) -upper/lower respiratory tract + kidneys (sinusitis, cavitary lung lesions, RPGN). p-ANCA (anti-MPO) is associated with MPA (microscopic polyangiitis) -kidneys + lungs (RPGN, pulmonary hemorrhage, no upper airway involvement) and EGPA (eosinophilic GPA, formerly Churg-Strauss) in ~50%. Why it matters
What is the ANCA-associated vasculitis treatment algorithm?
Induction: Pulse methylprednisolone 1g IV × 3 days → prednisone 1 mg/kg (max 80 mg) tapered over 6 months. PLUS rituximab 375 mg/m² weekly × 4 (preferred for PR3+/relapsing disease RAVE, 2010) OR cyclophosphamide (preferred for severe renal disease or DAH). If Cr > 5.7 or DAH → add plasmapheresis (removes pathogenic ANCA antibodies).
When do you use plasmapheresis in ANCA-associated vasculitis?
PLEX indications: (1) Severe renal failure (Cr > 5.7 mg/dL or dialysis-dependent) -though PEXIVAS, 2020 showed PLEX did NOT reduce death or ESKD overall, subgroup analysis and clinical practice still support it for dialysis-dependent patients where there may be salvageable renal function. (2) Diffuse alveolar hemorrhage (DAH) -PLEX removes pathogenic ANCA antibodies and can be life-saving in severe pulmonary hemorrhage
What is the initial treatment for suspected GCA with visual symptoms?
IV methylprednisolone 1g × 3 days IMMEDIATELY -do NOT wait for biopsy. Temporal artery biopsy can be done up to 2 weeks after starting steroids. Visual loss is often irreversible if treatment delayed even hours.
What drug has replaced cyclophosphamide as first-line induction for ANCA vasculitis?
RituximabRAVE, 2010 -equally effective for induction with fewer side effects. Preferred in relapsing disease. Cyclophosphamide still used but carries bladder cancer, infertility, and myelosuppression risks.
What is avacopan and why is it important?
C5a receptor inhibitorADVOCATE, 2021 -the first approved steroid-sparing agent for ANCA vasculitis. Can replace prednisone during induction (used with rituximab or cyclophosphamide). Superior sustained remission at 52 weeks.
How do you differentiate GPA from MPA?
GPA (Wegener's): upper + lower respiratory + renal. Cavitary lung nodules, sinusitis, saddle nose deformity. c-ANCA/PR3+. MPA: renal + pulmonary (DAH) without upper airway. No granulomas. p-ANCA/MPO+.
Clinical Examples
📋 Case 1, GPA (Granulomatosis with Polyangiitis)
Patient: 52M with chronic sinusitis refractory to antibiotics, new hemoptysis, and Cr rising 1.1 → 3.6 over 10 days. UA: RBC casts, proteinuria. CT chest: bilateral cavitary lung nodules.
Urgent renal biopsy, expect pauci-immune crescentic GN
Induction: rituximab 375 mg/m² weekly × 4 (preferred over cyclophosphamide for GPA) RAVE, 2010
Pulse methylprednisolone 500-1000 mg IV × 3 days → prednisone 1 mg/kg taper
Plasma exchange if severe renal involvement (Cr > 5.7) or DAH PEXIVAS, 2020
PJP prophylaxis with TMP-SMX (also prevents GPA relapse in upper airway)
Teaching point: c-ANCA/PR3 = GPA. Rituximab is now preferred over cyclophosphamide for induction in GPA, equal efficacy with better safety profile and superior for relapsing disease.
📋 Case 2, Giant Cell Arteritis with Vision Threat
Patient: 74F with new temporal headache × 2 weeks, jaw claudication, and 4 hours of monocular vision loss in right eye that resolved. ESR 98, CRP 8.4. Temporal artery tender and non-pulsatile.
Key findings: GCA with amaurosis fugax, ophthalmologic emergency. If untreated, permanent bilateral blindness occurs in 20% within days. ESR > 50 + age > 50 + new headache + jaw claudication = high probability.
Management:
IV methylprednisolone 1g daily × 3 days (vision-threatening GCA = IV steroids STAT)
Then prednisone 1 mg/kg daily with slow taper over 12-18 months
Temporal artery biopsy within 2 weeks (steroids do not alter biopsy for 10-14 days, do NOT delay steroids for biopsy)
Urgent ophthalmology consult
Tocilizumab 162 mg SQ weekly as steroid-sparing agent GiACTA, 2017
Teaching point: Never delay steroids in suspected GCA to wait for biopsy. Permanent blindness is the feared complication, treat first, biopsy second. Tocilizumab is now standard steroid-sparing therapy.
📋 Case 3, Eosinophilic Granulomatosis with Polyangiitis (EGPA)
Patient: 38F with severe asthma (diagnosed age 30), new peripheral neuropathy (foot drop), purpuric rash on lower extremities, eosinophils 4,200/μL. p-ANCA/MPO positive. CT chest: patchy GGOs.
EMG/NCV to characterize neuropathy; neurology consult
Echocardiogram, cardiac involvement is the #1 cause of death in EGPA
Teaching point: EGPA is the one ANCA vasculitis with asthma and eosinophilia. Cardiac involvement (myocarditis, pericarditis) occurs in ~60% and is the leading cause of mortality, always get an echo.
📣 Sample Presentation
One-Liner
"Mr. O'Connell is a 58-year-old presenting with hemoptysis, RPGN (Cr rising 1.2→4.8 in 4 days), and CT showing bilateral GGO. c-ANCA positive, anti-PR3 positive. Consistent with GPA (granulomatosis with polyangiitis)."
Key Points to Cover on Rounds
GPA with pulmonary-renal syndrome -c-ANCA/PR3+. Cr 4.8 (RPGN -UA showing RBC casts). CT chest: bilateral GGO (DAH). Hemoptysis -life-threatening. Treatment: (1) pulse methylprednisolone 1g IV × 3 days, (2) rituximab 375 mg/m² weekly × 4 weeks RAVE, 2010 (preferred for PR3+ -lower relapse rate than cyclophosphamide for relapsing disease), (3) emergent plasmapheresis initiated (Cr >5.7 or DAH → PLEX indicated). Biopsy: renal biopsy scheduled but NOT delaying treatment. Plan: daily Cr, Hgb, CXR for DAH monitoring. PCP prophylaxis with TMP-SMX. Hepatitis B/TB screening (before rituximab infusion #2).
Pulse methylprednisolone 1g × 3d → prednisone taper. Rituximab 375 mg/m² × 4 weeks RAVE, 2010 (PR3+/relapsing) OR cyclophosphamide (severe renal/DAH). PLEX if Cr > 5.7 or DAH.
💊 Maintenance
Rituximab 500 mg q6 months × 2 years MAINRITSAN, 2014 OR azathioprine. PCP prophylaxis (TMP-SMX). Calcium + vitamin D. Screen for TB/HBV before rituximab.
💊 Key Drugs
Methylprednisolone1g IV × 3d
Rituximab375 mg/m² weekly × 4
Cyclophosphamide15 mg/kg q2wk × 3 then q3wk
TMP-SMXDS daily (PCP prophylaxis)
⚠️ Pitfalls
Waiting for biopsy to start treatment (life-threatening disease -treat empirically)
Hospice = comfort-focused care for patients with prognosis ≤ 6 months. It's a Medicare benefit, not giving up. Patients and families consistently say they wish hospice was offered earlier. Know the disease-specific criteria.
🕊️ Hospice Eligibility
General Criteria (All Diseases)
Prognosis ≤ 6 months if disease runs its expected course (physician certification)
Patient (or surrogate) elects comfort-focused care -no curative intent treatments
General decline indicators: Karnofsky < 50% or PPS ≤ 50%, recurrent hospitalizations, progressive weight loss (> 10% in 6 months), declining functional status (increasing dependence in ADLs), albumin < 2.5
"Surprise question": "Would you be surprised if this patient died in the next 6 months?" If no → hospice referral appropriate. SUPPORT Study, 1995
Disease-Specific Criteria
Disease
Hospice-Eligible When
Heart Failure
NYHA Class IV at rest despite optimal therapy. EF ≤ 20%. Recurrent hospitalizations (≥ 3 in 6 months). Refractory to diuretics. Not a candidate for transplant/LVAD. Symptomatic hypotension limiting meds.
COPD / Pulmonary
FEV₁ < 30% predicted. Resting dyspnea on max therapy. O₂-dependent. Cor pulmonale / RHF. Recurrent exacerbations requiring hospitalization. pCO₂ > 50 or O₂ sat ≤ 88% on room air.
Dementia
FAST scale ≥ 7 (unable to ambulate, dress, bathe without assistance; < 6 intelligible words). Plus ≥ 1 complication in past 12 months: aspiration pneumonia, pyelonephritis, sepsis, decubitus ulcer stage III+, recurrent fever despite abx.
Cancer
Metastatic disease declining despite treatment or patient declines further disease-directed therapy. Poor performance status (ECOG 3–4). Progressive despite ≥ 2 lines of therapy. Hypercalcemia, malignant effusions, cachexia.
CKD stage 5 (GFR < 15) and patient declines or discontinues dialysis. Creatinine clearance < 10 mL/min (CrCl < 15 for diabetics). Uremic symptoms not being treated with RRT.
Stroke / Neurologic
Coma or persistent vegetative state. Dysphagia with aspiration + declining to PEG. Progressive decline despite rehab. Recurrent aspiration pneumonia.
What Hospice Provides
Covered by Medicare Part A -no out-of-pocket cost to patient for hospice services
Includes: RN visits (typically 1–3×/week), aide visits, social worker, chaplain, medications related to terminal diagnosis, DME (hospital bed, O₂, wheelchair), continuous care during crises, respite care (5 days), bereavement support for 13 months after death
Does NOT mean stopping all meds. Comfort medications continue (pain, nausea, dyspnea, anxiety). Disease-modifying meds may continue if they provide symptom benefit. Temel et al., 2010
Can be revoked at any time -patient can re-elect curative care if they change their mind
📋 On Rounds
Pimp Questions
A family asks: 'Does hospice mean you're giving up on my father?' How do you respond?
This is one of the most important conversations in medicine. The key reframe: 'Hospice isn't giving up -it's refocusing.' We're shifting from treatments that aren't working to treatments that improve quality of life. Hospice provides more care, not less: a nurse visits regularly, medications for comfort are covered, a chaplain and social worker support the family, and there's 24/7 phone access for crises.
What is the difference between hospice and palliative care?
Palliative care can be provided at any stage of serious illness, alongside curative treatment. It focuses on symptom management, goals of care, and quality of life. There is no prognosis requirement. Hospice is a specific Medicare benefit for patients with prognosis ≤ 6 months who elect comfort-focused care (no curative-intent treatments). Think of it this way: all hospice is palliative care, but not all palliative care is hospice.
What are the general hospice eligibility criteria beyond disease-specific ones?
General LCD (Local Coverage Determination) criteria: (1) Prognosis ≤ 6 months if disease runs its usual course (certified by 2 physicians), (2) Patient has elected comfort-focused care (no curative-intent treatments), (3) Functional decline: PPS (Palliative Performance Scale) ≤ 50% or declining, increasing dependence in ADLs, spending > 50% of day in bed
What symptoms can hospice patients still receive treatment for?
Hospice is NOT withdrawal of all treatment -it's refocusing on comfort. Hospice covers: (1) Pain: opioids, adjuvants (gabapentin, duloxetine, dexamethasone), nerve blocks, radiation for bone mets pain. (2) Dyspnea: morphine (first-line, low-dose), supplemental O₂ for comfort (not to chase SpO₂), fan directed at face, benzodiazepines if anxiety-related. (3) Nausea: ondansetron, haloperidol, metoclopramide, dexamethasone
📣 Sample Presentation
One-Liner
"Mrs. Martinez is a 78-year-old with metastatic pancreatic cancer, declining PPS (30%), unable to eat or ambulate, with increasing pain and dyspnea. Oncology confirms no further disease-directed therapy. Family meeting held -patient and family electing hospice."
Key Points to Cover on Rounds
Goals of care discussion completed using REMAP framework. Patient priorities: comfort, being at home, no more ER visits. Prognosis: weeks to low months (PPS 30%, declining trajectory). Code status: DNR/DNI documented and in chart. Hospice eligibility: metastatic cancer with declining functional status despite treatment -meets LCD criteria. Hospice agency contacted -admission tomorrow. Comfort medications ordered: morphine 5 mg PO q4h PRN pain, lorazepam 0.5 mg SL q4h PRN anxiety, ondansetron 4 mg q6h PRN nausea, glycopyrrolate 0.2 mg SL q4h PRN secretions. Unnecessary meds stopped: statin, metformin, lisinopril. Hospital bed and O₂ arranged for home.
PPS trending. Declining PPS confirms trajectory. Document for recertification
Medication review
Each visit
Are comfort meds working? Side effects? Need dose adjustment? Route change needed?
Caregiver assessment
Each visit
Burnout, coping, need for respite care, bereavement risk assessment
Labs
Generally NOT indicated
Labs rarely change management in hospice. Only draw if result will change comfort plan
Recertification
90 days, 90 days, then 60-day periods
Two physicians must certify continued eligibility. Document ongoing decline
Less is more in hospice monitoring. Stop checking labs that won't change management. Focus on symptoms, comfort, and family support -not numbers.
Monitoring Parameters -Opioid Rotation
Parameter
Frequency
Target / Action
Pain scores
q4h + 1h after each PRN dose
Target ≤ 4/10 or functional goals (e.g., able to ambulate, sleep). Track breakthrough use -if > 3 PRN doses/day, increase scheduled dose.
Sedation (Pasero Opioid-Induced Sedation Scale)
q4h with vitals (q1–2h first 24h post-rotation)
S = sleep, easy to arouse; 1 = awake, alert (acceptable); 2 = slightly drowsy (acceptable); 3 = frequently drowsy (hold dose, reduce); 4 = somnolent (hold, consider naloxone). Naloxone (Narcan) must be at bedside.
Respiratory rate
q4h (q1h first 24h of new opioid)
RR < 10 → hold opioid. RR < 8 or unresponsive → naloxone 0.04–0.4 mg IV (titrate to respirations, not consciousness). Monitor closely × 48–72h after rotation.
Bowel regimen
Daily assessment (BM frequency)
Start bowel regimen with ALL opioids, PEG 3350 (MiraLAX) 17g daily + senna 8.6 mg BID. No BM × 3 days → add bisacodyl or methylnaltrexone (Relistor) 12 mg SC if refractory. Tolerance does NOT develop to constipation. Do not use docusate (no better than placebo, AGA-ACG 2023).
Pruritus
Each assessment
Common opioid side effect (histamine release). Rotation may resolve it. Treat with low-dose nalbuphine 2.5 mg IV or hydroxyzine 25 mg PO. Avoid diphenhydramine (additive sedation).
Nausea
Each assessment
Often resolves with rotation. Ondansetron 4 mg IV/PO q8h PRN. Haloperidol 0.5–1 mg PO/IV for refractory opioid-induced nausea.
Functional status
Daily
Can the patient ambulate, participate in PT, perform ADLs? Pain management goal is function, not a number. Reassess total opioid requirements and consider multimodal adjuncts.
Monitor closely × 48–72h after any opioid rotation. Incomplete cross-tolerance means the new opioid may be unexpectedly potent. Have naloxone (Narcan) at bedside for all patients on opioid drips or after recent rotation. Adjust based on pain scores, breakthrough use, and side effect profile.
Prognostic tools: "Surprise question" -would you be surprised if this patient died in 6 months? Disease-specific criteria (see Criteria tab)
Goals of care discussion: Use REMAP framework -Reframe, Expect emotion, Map values, Align, Plan. Document in chart
Review active medications: Identify meds to continue (comfort) vs discontinue (no longer beneficial). Stop statins, metformin, vitamins, screening meds
Code status: Confirm and document DNR/DNI. Ensure POLST/MOLST form completed
Caregiver assessment: Evaluate family support, caregiver burnout risk, need for respite care
💊 Medications
Comfort Medications in Hospice
Symptom
First-Line
Dose
Notes
Pain
Morphine
5-10 mg PO q4h PRN; 2-4 mg IV/SC q2h PRN
Gold standard. Also treats dyspnea. Reduce dose in renal failure
Pain (renal failure)
Hydromorphone
0.5-1 mg PO q4h PRN
Safer than morphine in CKD/ESRD -no active metabolites
Pain (neuropathic)
Gabapentin
100-300 mg TID, titrate
Adjuvant for neuropathic pain. Also helps anxiety/insomnia
Dyspnea
Morphine
2.5-5 mg PO q4h PRN
Low-dose morphine is first-line. Fan to face also effective
Nausea
Ondansetron
4 mg PO/IV q6h PRN
First-line. Haloperidol 0.5-1 mg PO/IV q6h is excellent alternative
Secretions (death rattle)
Glycopyrrolate
0.2 mg SL/SC q4h PRN
Does not cross BBB (less delirium). Atropine 1% drops SL also works
Agitation/delirium
Haloperidol
0.5-2 mg PO/IV/SC q4-6h
First-line for terminal delirium. Add lorazepam if refractory
Anxiety
Lorazepam
0.5-1 mg PO/SL q4-6h PRN
Short-acting. Can be given sublingual if unable to swallow
Constipation
PEG 3350 + senna
Senna 2 tabs BID + MiraLAX 17g daily
Start with opioids. Methylnaltrexone SC if refractory. Docusate ineffective (AGA-ACG 2023)
Key principle: Route matters at end of life. When patients can no longer swallow, switch to SL (sublingual), SC (subcutaneous), or rectal routes. IV access is rarely needed in hospice.
⚡ Summary
Summary
The General Criterion
A prognosis of 6 months or less if the disease follows its expected course, with the patient choosing comfort-focused care over disease-directed treatment.The 6-month estimate is a good-faith clinical judgment, not a guarantee: patients who live longer are recertified, and they are not discharged for outliving a prediction.
Two General Markers Cross All Diseases
Declining functional status, Palliative Performance Scale 50% or less or Karnofsky under 50, and progressive weight loss or nutritional decline. Add recurrent hospitalizations and increasing dependence in activities of daily living. Documenting the trajectory matters more than any single value.
Know the Disease-Specific Criteria
Heart failure: NYHA IV with symptoms at rest despite optimal therapy, EF 20% or below.COPD: disabling dyspnea at rest, recurrent infections, cor pulmonale, resting hypoxemia.Dementia: FAST stage 7, non-ambulatory, minimal speech, plus a complication such as aspiration pneumonia or a pressure ulcer.Liver disease: INR above 1.5 with albumin below 2.5 plus refractory ascites, SBP or hepatorenal syndrome.
Hospice Is Not Giving Up
It is a change in the goal of treatment, not a withdrawal of care.Patients on hospice frequently live as long or longer than those pursuing further disease-directed treatment in comparable populations, and quality of life is consistently better. Say that plainly, because families hear 'hospice' as abandonment.
Know What It Actually Provides
An interdisciplinary team, nursing visits, a 24-hour on-call line, medications related to the terminal diagnosis, equipment, respite care, social work, chaplaincy and 13 months of bereavement support for the family.It is mostly delivered at home, which is where most patients say they want to be.
It Does Not Mean No Treatment
Antibiotics, radiation for pain, transfusions and even some hospital care can be appropriate if they serve comfort.The test is whether the intervention relieves symptoms, not whether it is 'aggressive', and framing it that way removes the false choice families think they are being offered.
Change the Monitoring
Less is more: stop checking labs that will not change management.Focus on symptoms, comfort and family support, not numbers. Routine glucose checks, daily bloods and vital sign rounds cause discomfort and distress without benefit, and stopping them is an active clinical decision worth writing down.
Route Matters at the End of Life
When patients can no longer swallow, switch to sublingual, subcutaneous or rectal routes; IV access is rarely needed in hospice.Refer early rather than in the last days: very short stays deny families most of the benefit, and late referral is the commonest failure. Do not equate hospice with palliative care, which runs alongside disease-directed treatment at any stage.
⚡ Management
Hospice Management Priorities
Symptom management is the primary goal. Pain, dyspnea, nausea, agitation -treat aggressively. There is no ceiling dose for opioids in hospice if symptoms persist
Anticipatory prescribing: Write PRN orders for common end-of-life symptoms BEFORE they occur -pain, dyspnea, secretions, agitation, nausea, fever
Crisis plan: Document what to do for symptom emergencies. Continuous care (24h nursing) available for crises. Avoid unnecessary 911 calls/ER visits
Family education: Prepare family for signs of active dying -Cheyne-Stokes breathing, mottling, decreased urine output, terminal restlessness, changes in consciousness
Spiritual/psychosocial care: Chaplain, social worker, life review, legacy work. Address existential distress
Pain: morphine (first-line). Dyspnea: morphine + fan at face. Nausea: ondansetron, haloperidol. Secretions: glycopyrrolate/atropine drops. Agitation: haloperidol, lorazepam.
💊 What to Stop
Statins, metformin, vitamins, screening tests, antihypertensives (unless symptomatic). Each med removed = reduced pill burden + side effects. Focus on comfort and quality of life.
💊 Key Drugs
Morphine2-5 mg PO/SL q2-4h PRN
Lorazepam0.5-1 mg SL q4h PRN
Ondansetron4 mg q6h PRN
Glycopyrrolate0.2 mg SL q4h PRN
⚠️ Pitfalls
Hospice = giving up (it's active symptom management + support)
Continuing aggressive meds that add no comfort benefit
Not offering hospice early enough (many patients referred too late)
Not supporting caregivers (burnout is real -hospice provides respite care)
Related Topics
Code Status & Advance DirectivesFamily Meeting FrameworkGoals of Care & Symptom ManagementNon-Opioid Symptom ManagementOpioid Rotation ConversionPalliative Extubation
Palliative Care
Opioid Rotation & Conversion
Evidence-based approach to opioid rotation, equianalgesic dosing, and non-opioid adjuvant therapy for residents managing pain in palliative and inpatient settings.
💊 Opioid Rotation Protocol
→ Open the interactive Opioid Conversion calculator, computes OME, shows equivalents across morphine/oxycodone/hydromorphone/fentanyl patch + IV drip, and applies cross-tolerance reduction automatically. Methadone is intentionally blocked (non-linear; consult palliative care).
When to Rotate
Intolerable side effects (nausea, sedation, pruritus, myoclonus) despite dose adjustments
Inadequate analgesia despite dose escalation (true tolerance vs ceiling effect)
Renal failure (rotate away from morphine -M6G accumulates) McPherson et al., 2018
Route change required (PO → IV, or vice versa)
4-Step Conversion Process
Step 1
Calculate total 24h dose of current opioid (scheduled + PRN breakthrough actually used). Example: morphine 30 mg PO q4h (scheduled) + 15 mg PO × 4 breakthrough = 210 mg PO morphine/24h.
Step 2
Convert to equianalgesic dose of new opioid using conversion table (see Opioid Conversions). 210 mg PO morphine ÷ 30 × 20 = 140 mg PO oxycodone/24h equivalent.
Step 3
Reduce by 25–50% for incomplete cross-tolerance. Different opioids bind to different μ-receptor subtypes → previous tolerance doesn't fully transfer. 140 × 0.75 = 105 mg PO oxycodone/24h. Use 50% reduction if: elderly, frail, renal/hepatic impairment, or switching to methadone.
Step 4
Split into scheduled + PRN. Scheduled: 105 ÷ 24h = ~4.4 mg/hr → oxycodone ER 45 mg q12h (or round to nearest available). PRN breakthrough: 10–15% of total 24h dose = oxycodone IR 10–15 mg q3h PRN.
ALWAYS reduce the calculated equianalgesic dose by 25–50%. Skipping this step is the #1 cause of opioid rotation overdose. The cross-tolerance reduction is non-negotiable. McPherson et al., 2018For methadone conversions: ALWAYS consult pharmacy or palliative care -methadone conversion is non-linear and complex. CDC Opioid Prescribing Guideline, 2022
Fentanyl Patch Conversion: Only for patients on stable opioid doses >= 60 mg oral morphine equivalents/day for >= 1 week. Calculate total 24h OME, then: patch mcg/hr ≈ total daily OME / 2. Example: 120 mg OME/day ≈ fentanyl 50 mcg/hr patch. Apply new patch, continue current short-acting opioid for 12-24h (absorption delay). Remove old opioid ER formulation when patch is applied.
Naloxone Co-prescribing: Co-prescribe naloxone (Narcan) for all patients on >= 50 mg oral morphine equivalents/day, concurrent benzodiazepines, history of overdose, or substance use disorder. Educate patient/family on use. Naloxone duration (30-90 min) may be shorter than opioid duration - observe for re-sedation. CDC Opioid Guideline, 2022
💊 Non-Opioid Adjuvants
Pain Type
Agent
Notes
Neuropathic
Gabapentin (Neurontin) 100–300 mg TID → titrate to 1200 mg TID or pregabalin (Lyrica) 75 mg BID → 300 mg BID
First-line for neuropathic pain. Start low, titrate slow (sedation, dizziness). Reduce dose in CKD. Also: duloxetine 30–60 mg daily (good for diabetic neuropathy). NeuPSIG (Finnerup), 2015
Dexamethasone (Decadron) 8–16 mg IV daily + octreotide (Sandostatin) 100–300 mcg SC TID + glycopyrrolate for secretions
Medical management for malignant bowel obstruction when surgery is not appropriate.
Visceral / somatic
Acetaminophen (Tylenol) 1g q6h (scheduled, not PRN) + NSAIDs (ibuprofen 400–600 mg TID or ketorolac 15 mg IV q6h × 5 days max)
Scheduled acetaminophen reduces opioid requirements by 20–30%.Elia et al., 2005 NSAIDs: avoid in CKD, GI bleed risk, CHF. Ketorolac: max 5 days (renal toxicity).
Muscle spasm
Baclofen 5–10 mg TID or tizanidine 2–4 mg TID
Avoid cyclobenzaprine in elderly (anticholinergic → delirium). Baclofen: reduce dose in CKD (renally cleared).
🔄 Updated Practice: Old teaching: pain is the "5th vital sign" -treat aggressively with opioids. This contributed to the opioid epidemic. Current practice: multimodal analgesia first (acetaminophen + NSAIDs/ketorolac + gabapentin/pregabalin + regional/local anesthesia). Opioids are for severe pain refractory to multimodal therapy, at the lowest effective dose, for the shortest duration. For chronic non-cancer pain, opioids should generally be avoided -evidence shows minimal long-term benefit with significant harm (addiction, hyperalgesia, overdose).
📋 On Rounds
Pimp Questions
Why do you reduce the equianalgesic dose by 25–50% when rotating opioids?
Incomplete cross-tolerance. Different opioids bind to slightly different μ-opioid receptor subtypes and have different receptor binding profiles (μ1, μ2, δ, κ). When a patient develops tolerance to one opioid, that tolerance does NOT fully transfer to a new opioid -the new drug will be more potent than the conversion table suggests.
When should you rotate opioids vs simply increase the dose of the current opioid?
Rotate (switch to a different opioid) when: (1) intolerable side effects despite dose adjustments (persistent nausea, myoclonus, pruritis, sedation -a different opioid may not cause the same side effect), (2) true analgesic tolerance with escalating doses and diminishing returns (switching resets cross-tolerance)
What is the most dangerous opioid rotation and why?
Rotation TO methadone is the most dangerous. Methadone has unique pharmacology that makes standard equianalgesic tables unreliable: (1) Long and variable half-life (15-60 hours) -steady state takes 5-7 days, so dose adjustments cause delayed toxicity. (2) Incomplete cross-tolerance is MORE pronounced with methadone than other opioids -the standard tables OVERESTIMATE the required methadone dose
What is the equianalgesic dose table and what are its limitations?
Key conversions (oral): Morphine 30 mg = Oxycodone 20 mg = Hydromorphone 6 mg = Hydrocodone 30 mg. IV conversions: Morphine 10 mg IV = Hydromorphone 1.5 mg IV. Oral-to-IV ratio: morphine 3:1 (30 mg PO = 10 mg IV), hydromorphone 5:1 (6 mg PO ≈ 1.5 mg IV). Limitations: (1) Tables are based on single-dose studies in opioid-naive patients -do NOT apply directly to chronic opioid patients
Why is morphine avoided in patients with renal failure?
Morphine is metabolized to morphine-6-glucuronide (M6G), a pharmacologically active metabolite that is renally cleared. In CKD/ESRD, M6G accumulates and causes prolonged sedation, respiratory depression, and myoclonus - effects that can persist for days. Hydromorphone (less active metabolite accumulation) or fentanyl (no active metabolites, hepatically cleared) are safer alternatives. McPherson et al., 2018
A patient on morphine 30 mg PO q4h (180 mg/day) needs rotation to IV hydromorphone. Calculate the dose.
Step 1: Total 24h oral morphine = 180 mg. Step 2: Convert to IV morphine (PO:IV = 3:1) = 60 mg IV morphine/day. Step 3: Convert to IV hydromorphone (morphine 10 mg IV = hydromorphone 1.5 mg IV) = 60 x 1.5/10 = 9 mg IV hydromorphone/day. Step 4: Reduce 25-50% for cross-tolerance = 4.5-6.75 mg/day. Final: hydromorphone ~0.2-0.3 mg/hr continuous or ~1 mg IV q4h with 0.5 mg q2h PRN.
What is opioid-induced hyperalgesia and how does it differ from tolerance?
Opioid-induced hyperalgesia (OIH) is paradoxical increased pain sensitivity caused by opioids themselves. Unlike tolerance (where the same dose produces less effect, requiring dose escalation for the SAME pain), OIH causes NEW or WORSENING pain that is often diffuse and qualitatively different from the original pain. The key distinction: with tolerance, increasing the dose helps. With OIH, increasing the dose makes it WORSE. Treatment: rotate opioids, reduce total dose, add NMDA antagonists (ketamine, methadone). opioid rotation and NMDA antagonists.">Lee et al., 2011
What are the unique dangers of fentanyl patch prescribing?
Fentanyl patches are for STABLE opioid requirements only - never for opioid-naive patients or acute pain (FDA black box). Key dangers: (1) 12-24 hour delay to peak effect - fatal if dose is too high. (2) Drug continues releasing 12-24h AFTER removal. (3) Heat exposure (fever, heating pads, hot baths) dramatically increases absorption and can cause fatal overdose. (4) Patches can be accidentally transferred to caregivers or children through skin contact. (5) CYP3A4 inhibitors increase fentanyl levels. Nelson & Schwaner, 2009
When should you consult palliative care for pain management?
Presentation: 72M with advanced pancreatic cancer on morphine SR 60 mg PO BID + morphine IR 15 mg PO q4h PRN (using 4 doses/day). Complaints: severe nausea, myoclonus (arm jerks), and pruritus despite antiemetics. Cr 1.8 (baseline 0.9). Total 24h morphine: 120 mg SR + 60 mg PRN = 180 mg PO/day.
Conversion: 180 mg PO morphine / 5 = 36 mg PO hydromorphone equivalent. Apply 25% reduction (rising Cr) = 27 mg/day. New regimen: hydromorphone ER 12 mg PO q12h (24 mg scheduled) + hydromorphone IR 3 mg PO q3h PRN (10-15% of TDD). Bowel regimen: PEG 3350 + senna (docusate removed per AGA-ACG 2023 - no benefit). AGA-ACG, 2023
Outcome: Nausea and myoclonus resolved within 48h (morphine-specific side effects). Pain controlled with 1-2 breakthrough doses/day.
PCA to Oral Conversion at Discharge
Presentation: 45F post-exploratory laparotomy, POD 3, tolerating PO. Current: hydromorphone PCA - basal rate 0 mg/hr, demand dose 0.2 mg q10min. Over past 24h: used 18 demands (3.6 mg IV hydromorphone/day). Ready for PO transition.
Conversion: 3.6 mg IV hydromorphone x 4 (IV:PO ratio) = 14.4 mg PO hydromorphone/day. No cross-tolerance reduction needed (same drug, just route change). New regimen: hydromorphone 2 mg PO q4h scheduled (12 mg/day) + hydromorphone 2 mg PO q3h PRN. Also: scheduled acetaminophen 1g q6h (reduces opioid requirement 20-30%), ibuprofen 400 mg TID if no contraindications. Taper plan: reduce by 25% every 2-3 days as surgical pain resolves.
Key point: Always add multimodal adjuvants when converting to oral. PCA-to-PO conversion is based on actual PCA usage, not the demand settings.
Dangerous Methadone Conversion
Presentation: 58M with metastatic lung cancer on oxycodone ER 80 mg BID + oxycodone IR 20 mg q4h PRN (using 4 doses/day). Total: 240 mg oxycodone/day. Attending requests rotation to methadone due to cost and neuropathic pain component (methadone has NMDA antagonist activity).
Conversion: 240 mg oxycodone = ~360 mg oral morphine equivalents (oxycodone x 1.5). At this high dose (>300 mg OME), methadone conversion is NOT 1:1 - the ratio is approximately 12:1 to 20:1 (morphine:methadone). Using 15:1 ratio: 360/15 = 24 mg methadone/day. Further reduce 50% for safety = 12 mg/day. Start methadone 5 mg PO TID (15 mg/day) with oxycodone IR 10 mg q4h PRN for breakthrough during transition.
Critical teaching: Methadone reaches steady state in 5-7 days due to long half-life. Do NOT increase methadone dose during the first week. Deaths occur when clinicians increase the dose on day 2-3 because the patient reports pain - the methadone hasn't peaked yet. QTc monitoring required (obtain baseline ECG, repeat at steady state). Weschules & Bain, 2008
📣 Sample Presentation
One-Liner
"Mr. Lee is a 64-year-old with metastatic prostate cancer on sustained-release morphine 60 mg BID + morphine IR 15 mg q4h PRN (using 4 doses/day) being rotated to hydromorphone due to intolerable nausea, myoclonus, and pruritus."
Key Points to Cover on Rounds
Current 24h opioid: morphine SR 120 mg + IR 60 mg = 180 mg oral morphine/day. Equianalgesic conversion: oral morphine 180 mg → oral hydromorphone (÷5) = 36 mg/day. Apply 25% reduction for incomplete cross-tolerance → 27 mg/day. New regimen: hydromorphone ER 12 mg PO BID (24 mg scheduled) + hydromorphone IR 3 mg PO q3h PRN (10-15% of TDD for breakthrough). Bowel regimen continued: PEG 3350 + senna. Antiemetic PRN. Plan: monitor for first 48-72h, adjust based on pain scores and breakthrough use. Expect resolution of morphine-specific side effects.
Monitoring Parameters -Opioid Rotation
Parameter
Frequency
Target / Action
Pain scores
q4h + 1h after each PRN dose
Target ≤ 4/10 or functional goals (e.g., able to ambulate, sleep). Track breakthrough use -if > 3 PRN doses/day, increase scheduled dose.
Sedation (Pasero Opioid-Induced Sedation Scale)
q4h with vitals (q1–2h first 24h post-rotation)
S = sleep, easy to arouse; 1 = awake, alert (acceptable); 2 = slightly drowsy (acceptable); 3 = frequently drowsy (hold dose, reduce); 4 = somnolent (hold, consider naloxone). Naloxone (Narcan) must be at bedside.
Respiratory rate
q4h (q1h first 24h of new opioid)
RR < 10 → hold opioid. RR < 8 or unresponsive → naloxone 0.04–0.4 mg IV (titrate to respirations, not consciousness). Monitor closely × 48–72h after rotation.
Bowel regimen
Daily assessment (BM frequency)
Start bowel regimen with ALL opioids, PEG 3350 (MiraLAX) 17g daily + senna 8.6 mg BID. No BM × 3 days → add bisacodyl or methylnaltrexone (Relistor) 12 mg SC if refractory. Tolerance does NOT develop to constipation. Do not use docusate (no better than placebo, AGA-ACG 2023).
Pruritus
Each assessment
Common opioid side effect (histamine release). Rotation may resolve it. Treat with low-dose nalbuphine 2.5 mg IV or hydroxyzine 25 mg PO. Avoid diphenhydramine (additive sedation).
Nausea
Each assessment
Often resolves with rotation. Ondansetron 4 mg IV/PO q8h PRN. Haloperidol 0.5–1 mg PO/IV for refractory opioid-induced nausea.
Functional status
Daily
Can the patient ambulate, participate in PT, perform ADLs? Pain management goal is function, not a number. Reassess total opioid requirements and consider multimodal adjuncts.
Monitor closely × 48–72h after any opioid rotation. Incomplete cross-tolerance means the new opioid may be unexpectedly potent. Have naloxone (Narcan) at bedside for all patients on opioid drips or after recent rotation. Adjust based on pain scores, breakthrough use, and side effect profile.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Overview -Opioid Rotation & Pain Management
See the tabs above for the complete clinical reference: Workup, Management, Medications, Monitoring, Rounds, Summary, and One Pager.
🧪 Workup
Pre-Rotation Assessment -Opioid Rotation
Pain assessment -numeric rating scale (0–10), functional goals ("What would you like to be able to do?"), pain quality (nociceptive vs neuropathic), exacerbating/relieving factors. The number alone is insufficient.
Current opioid regimen -exact drug, dose, route, frequency (scheduled + PRN). Calculate total 24h opioid consumption including all breakthrough doses actually taken.
Equianalgesic calculation -convert current total 24h dose to oral morphine equivalents (OME), then convert to the new opioid using equianalgesic table. Apply 25–50% reduction for incomplete cross-tolerance.
Reason for rotation -intolerable side effects (nausea, myoclonus, pruritus, sedation), analgesic tolerance despite dose escalation, cost/formulary, route change needed (PO → IV or vice versa)
Renal function (BMP, CrCl) -affects opioid metabolism. Morphine: avoid in CKD (active metabolite M6G accumulates → prolonged sedation/respiratory depression). Hydromorphone: safer in CKD but metabolite H3G can accumulate. Fentanyl: safest in renal failure (no active metabolites).
Hepatic function (LFTs) -most opioids are hepatically metabolized (CYP3A4, CYP2D6). Severe liver disease → reduced clearance → dose reduce and extend intervals. Methadone especially affected.
⚡ Management
Management -Opioid Rotation
See the Rotation Steps tab above for the full 4-step conversion process with equianalgesic calculations and cross-tolerance reduction guidance.
Preferred in renal impairment. 5× more potent than morphine PO. IR: q3–4h. ER: q12–24h.
Oxycodone (OxyContin)
20 mg
N/A (no IV form)
-
1.5× more potent than morphine PO. IR: q4–6h. ER: q12h.
Fentanyl patch (Duragesic)
12 mcg/hr patch ≈ 30 mg PO morphine/24h
Variable
-
For stable opioid requirements ONLY (not acute pain). Takes 12–24h to reach peak effect. No active metabolites -safest in CKD/ESRD. Mercadante & Bruera, 2016
Methadone (Dolophine)
Non-linear conversion
Variable
~2:1
DANGER t½ = 15–60h. QTc prolongation. NMDA antagonist. Use dedicated methadone conversion tables -NOT the standard equianalgesic table. Weschules & Bain, 2008Consult pharmacy or palliative care.
After calculating the equianalgesic dose, reduce the new opioid by 25–50% for incomplete cross-tolerance. This is non-negotiable. Use the 50% reduction for: elderly, hepatic/renal impairment, methadone conversions, or high-dose rotations (> 200 mg OME/day). Methadone has additional unique risks -always consult an experienced prescriber.
⚡ Summary
Summary
Know Why You Are Rotating
Inadequate analgesia despite escalation, intolerable side effects, opioid-induced neurotoxicity (myoclonus, hyperalgesia, delirium), a change in route or in organ function, or cost and availability.Rotating for uncontrolled pain that is actually neuropathic or psychological in origin will not work, so define the problem before switching the drug.
Follow the Four Steps
Calculate the total 24-hour oral morphine equivalent of everything the patient is taking.Convert to the new agent using an equianalgesic table.Reduce for incomplete cross-tolerance.Divide into a scheduled dose plus breakthrough, with breakthrough at about 10 to 15% of the total daily dose.
The Cross-Tolerance Reduction Is Non-Negotiable
Always reduce the calculated equianalgesic dose by 25 to 50%.Skipping this step is the single commonest cause of opioid rotation overdose: tolerance to one opioid does not transfer completely to another, so the calculated dose is more potent than expected in that patient.
Methadone Is a Different Animal
Its conversion ratio is non-linear and rises with the previous dose, and it has a long and variable half-life with NMDA activity and QT prolongation.Consult palliative care or pain before converting to methadone, and get a baseline ECG. Standard equianalgesic tables do not apply.
Fentanyl Patches Have Entry Requirements
Only for patients already on a stable dose of at least 60 mg oral morphine equivalents per day for at least a week.Patch mcg/h is roughly total daily OME divided by 2 (120 mg OME/day is about 50 mcg/h). It takes 12 to 24 h to take effect and just as long to wear off, so it is never the drug for acute or unstable pain, and fever or a heat source accelerates absorption unpredictably.
Monitor for 48 to 72 Hours After Any Rotation
Incomplete cross-tolerance means the new opioid may be unexpectedly potent.Keep naloxone at the bedside for anyone on an opioid infusion or recently rotated, and reassess the dose at least daily rather than waiting for the next scheduled review.
Multimodal First, Opioid as One Component
The 'pain as the fifth vital sign' era, treating aggressively with opioids, contributed to the opioid epidemic.Start with acetaminophen plus an NSAID or ketorolac, and add gabapentinoids or a tricyclic for neuropathic pain, plus regional and non-pharmacologic approaches. Opioid-sparing is the goal, not opioid-avoidance: untreated severe pain is also harm.
Prescribe Naloxone and Manage the Bowels
Co-prescribe naloxone for anyone on 50 mg OME per day or more, on concurrent benzodiazepines, with a history of overdose, or with substance use disorder, and teach the family to use it. Start a bowel regimen with the first opioid dose: constipation is the one side effect to which no tolerance develops, and it is what makes patients stop effective analgesia.
RoundsRx Infographic Series · #178 · Oncology & Palliative · PDF 134 KB
Text version
Opioid Rotation -Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
OPIOID ROTATION -AT A GLANCE
📋 When to rotate: Intolerable side effects, tolerance, poor pain control, renal failure (morphine metabolites). 📊 Equianalgesic: PO morphine 30 = oxycodone 20 = hydromorphone 6. IV morphine 10 = hydromorphone 1.5. ⚠️ Cross-tolerance: Always reduce calculated dose by 25–50% -cross-tolerance is INCOMPLETE. 🚨 Methadone: Non-linear conversion, long t½ (15–60h), QTc risk. Use dedicated tables. Experienced prescribers only. 📈 Monitor: Closely × 48–72h after rotation. Pain scores, sedation, RR. Narcan at bedside.
Related Topics
Code Status & Advance DirectivesFamily Meeting FrameworkGoals of Care & Symptom ManagementHospice Eligibility CriteriaNon-Opioid Symptom ManagementPalliative Extubation
Palliative Care
Goals of Care & Symptom Management
Palliative care is not hospice. It's about aligning treatment with the patient's values at any stage of illness. Every resident should be able to lead a goals-of-care conversation and manage common symptoms at end of life.
🤝 Goals of Care Conversation
When to Have the Conversation
Any new serious diagnosis (advanced cancer, end-stage organ failure, severe dementia)
Significant clinical deterioration or ICU admission
Repeated hospitalizations for chronic progressive disease
"Would you be surprised if this patient died in the next year?" -if no, initiate GOC discussion.
Framework -REMAP
Step
What to Say
R -Reframe
"I want to step back and talk about the big picture of what's going on."
E -Expect emotion
Pause. Acknowledge. "I can see this is hard to hear." NURSE: Name, Understand, Respect, Support, Explore.
M -Map values
"What matters most to you?" "What does a good day look like?" "Are there things worse than death to you?"
A -Align
"Based on what you've told me -that being independent and not suffering are most important -I'd recommend..."
P -Plan
Concrete next steps. Document. Communicate with team. Revisit as things change.
Code Status Discussion
Avoid: "Do you want us to do everything?" (misleading -implies no CPR = giving up)
Better: "If your heart were to stop, CPR involves chest compressions that often break ribs, a breathing tube, and electric shocks. In someone with your condition, the chance of surviving to leave the hospital is about ___%. Given what you've told me about what matters most to you, I would recommend..."
Make a recommendation. Patients want guidance, not just options.
💊 Symptom Management
Symptom
First-Line
Notes
Pain
Morphine (MS Contin) 2–5 mg IV/SC q2–4h PRN or oxycodone 5–10 mg PO q4h. Scheduled + PRN for constant pain.
Titrate to comfort. No ceiling for opioids in end-of-life care. Add adjuncts: acetaminophen (scheduled), gabapentin (neuropathic), dexamethasone (bone mets, inflammation).
Dyspnea
Morphine (MS Contin) 2–4 mg IV/SC q2–4h PRN. Fan to face. Oxygen if hypoxic.
Opioids are the most effective treatment for dyspnea in palliative care. They reduce the sensation of breathlessness centrally. Low doses are safe and don't hasten death Opioids for Dyspnea Trial, 2003. Anxiolytics (lorazepam 0.5–1 mg) if anxiety-driven.
Nausea / vomiting
Ondansetron (Zofran) 4–8 mg IV q6h or haloperidol 0.5–1 mg IV q6h (good for opioid-induced or chemical causes)
Match anti-emetic to mechanism: chemoreceptor trigger zone → haloperidol/ondansetron. GI dysmotility → metoclopramide. Raised ICP → dexamethasone. Vestibular → meclizine.
Anticholinergics reduce new secretion production. Suctioning is uncomfortable and often futile. Reposition to lateral. Reassure family -the sound is often more distressing to family than to the patient.
Rule out reversible causes first (urinary retention, constipation, pain, medication). If actively dying and refractory → palliative sedation with midazolam or phenobarbital infusion (requires palliative care consult + family discussion).
🔍 Overview
Overview
Palliative care improves quality of life through symptom management, GOC discussions, and psychosocial support. Appropriate at any illness stage -concurrent with curative treatment. Palliative care ≠ hospice.
🧪 Workup
Workup
ESAS symptom scores (0-10)
Functional status -PPS, ECOG
Prognostication -surprise question, PPI
Advance directives review
Psychosocial/spiritual screening
🚨 Management
Management
Pain: WHO ladder + adjuvants (gabapentin, duloxetine, dexamethasone)
Dyspnea: Morphine 2-5mg SL + fan at face + O₂ if hypoxic
An attending asks you to 'make the patient comfortable' -what specific orders do you write?
This is a practical question that catches many interns off guard. A complete comfort care order set includes: (1) Pain: morphine 2–5 mg IV/SC q2h PRN (or current opioid equivalent). Scheduled if constant pain. (2) Dyspnea: morphine 2–4 mg IV/SC q2h PRN (opioids are first-line for dyspnea). (3) Anxiety/agitation: lorazepam 0.5–1 mg IV/SC q4h PRN. (4) Secretions (death rattle): glycopyrrolate 0.2 mg IV/SC q4h PRN or atropine 1% drops SL q4h.
How do you know when to give morphine for dyspnea vs when it will hasten death?
This is one of the most common misconceptions in medicine. Appropriately dosed opioids for dyspnea do NOT hasten death. This was definitively shown by Abernethy et al. (2003): low-dose morphine significantly improved dyspnea without affecting respiratory rate, oxygen saturation, or survival.
What is the REMAP framework for goals of care conversations?
R eframe -Set the stage: "I want to make sure we're on the same page about what's happening." Clarify medical reality without jargon. E xpect emotion -Pause. Let silence work. Acknowledge: "I can see this is really hard." Don't fill silence with medical facts.
How do you manage terminal dyspnea?
Dyspnea is the symptom patients and families fear most in the terminal phase. Management: (1) Morphine is first-line -2-5 mg PO/SL/SQ q2-4h PRN. Reduces central perception of breathlessness without clinically significant respiratory depression at appropriate doses Opioids for Dyspnea Trial, 2003. (2) Fan directed at face -stimulates V2 branch of trigeminal nerve → reduces sensation of air hunger. Evidence-based and free
Clinical Examples
📋 Case 1, Transitioning to Comfort Measures
Patient: 78M with metastatic pancreatic cancer, ECOG 4, declining PO intake × 2 weeks. Family ambivalent about hospice. Current: morphine PCA, ondansetron, IV fluids.
Key findings: PPS 20%. Recurrent SBO from peritoneal carcinomatosis. No further oncologic options. Patient previously expressed "no machines" but no formal advance directive.
Management:
Goals of care conversation using REMAP framework with patient and family
Transition PCA to SQ morphine infusion 2 mg/hr for comfort
D/C IV fluids (contributes to secretions and edema at end of life)
Add glycopyrrolate 0.2 mg SQ q4h PRN for secretions
Hospice referral, inpatient hospice given symptom burden
Teaching point: IV fluids at end of life often worsen symptoms (secretions, edema, dyspnea). Discontinuing is not "giving up", it is symptom management.
📋 Case 2, Refractory Cancer Pain
Patient: 62F with metastatic breast cancer to bone. Pain 9/10 despite oxycodone 40 mg q4h. Somnolent but still reporting severe pain. Cr 2.4 (new).
Key findings: Opioid neurotoxicity (myoclonus, somnolence with persistent pain). Renal failure accumulating active metabolites. Current opioid dose equivalent: 360 MME/day.
Management:
Opioid rotation to hydromorphone (no active renal metabolites), reduce by 25-50% for cross-tolerance
Dexamethasone 4 mg IV q6h for bone pain and peritumoral edema
Radiation oncology consult for palliative XRT to painful metastases
Add gabapentin 100 mg TID (renal dose) for neuropathic component
IV hydration to address prerenal AKI
Teaching point:Opioid rotation is indicated when dose escalation causes toxicity without adequate analgesia. Hydromorphone and fentanyl are preferred in renal failure.
📋 Case 3, Terminal Dyspnea Management
Patient: 85M with end-stage IPF, on 15L high-flow, SpO₂ 78%. DNR/DNI. Progressive dyspnea with visible distress. Family at bedside.
Key findings: Terminal respiratory failure. No reversible cause. Patient previously documented desire for comfort-focused care. PPS 10%.
Management:
Morphine 2 mg IV q15min PRN for dyspnea (titrate to comfort, not respiratory rate)
Fan directed at face, stimulates trigeminal V2 branch, reduces air hunger
Lorazepam 0.5 mg SL q4h PRN for anxiety component
Continue supplemental O₂ for comfort (not to target SpO₂)
Proactive family communication: normalize Cheyne-Stokes breathing, explain death rattle
Teaching point: Morphine for dyspnea does not hasten death at appropriate doses. The principle of double effect permits symptom management even if it theoretically shortens life.
📣 Sample Presentation
One-Liner
"Mr. Washington is a 82-year-old with advanced dementia (FAST 7c), recurrent aspiration pneumonia × 3 admissions this year, and worsening functional status. Family requesting "everything" but primary team is concerned about escalating interventions."
Key Points to Cover on Rounds
Goals of care conversation needed. Current trajectory: advanced dementia with recurrent aspiration -antibiotics are treating the symptom, not the underlying cause. REMAP framework used: R (reframe: "his dementia is causing the pneumonias -antibiotics can't fix that"), E (expect emotion -family is grieving), M (map values: "what would he say if he could tell us?"), A (align), P (plan). Family shared that he previously said he "never wanted to be a burden." After discussion, family chose: comfort-focused care, treat symptoms (dyspnea with morphine 2 mg SL q2h PRN), no more antibiotics for aspiration, no intubation, no ICU. Hospice referral initiated. Palliative care following.
⚡ Summary
Summary
Palliative Care Is Not Hospice
It is about aligning treatment with the patient's values at any stage of illness, alongside disease-directed therapy.Hospice is a subset for patients with a prognosis of about 6 months who have chosen comfort-focused care.Conflating the two is why referrals are refused, so name the difference explicitly when you raise it.
Refer Early
Early palliative care improves quality of life, reduces depression and, in some populations such as metastatic lung cancer, is associated with longer survival (Temel). Trigger the conversation at diagnosis of a serious illness, at a change in trajectory, at recurrent admissions, or when the surprise question is answered 'no', not in the last week.
Use REMAP
Reframe why the status quo is not working, Expect emotion and respond to it, Map what matters to the patient, Align with those values, Plan the treatment that fits. Mapping before planning is the whole point: recommendations built on stated values are accepted, and recommendations built on prognosis alone are resisted.
Ask About Values, Not About Interventions
'What matters most to you?', 'What would an unacceptable outcome look like?', 'What are you hoping for, and what are you worried about?'Do not open with the ventilator and the feeding tube: a list of procedures forces a technical decision onto a frightened family and produces answers that do not reflect what they actually want.
Make a Recommendation
'Based on what you have told me matters to your mother, I would recommend...'Never ask 'do you want us to do everything?', which is unanswerable and implies the alternative is nothing. Sharing the burden of the decision is a clinical duty, not a paternalistic overreach.
Treat Dyspnea With Opioids
Low-dose opioids are the most effective treatment for refractory breathlessness, and at appropriate doses they do not hasten death. Add a fan to the face, positioning and treatment of the reversible cause. Oxygen helps only if the patient is hypoxemic; in a normoxic patient it adds nothing over a fan.
Match the Symptom to the Drug
Nausea: identify the pathway, so ondansetron for chemotherapy and metoclopramide for gastroparesis, haloperidol for opioid or metabolic causes.Terminal secretions: reposition, stop artificial hydration, glycopyrrolate or scopolamine, and explain that it distresses the family rather than the patient.Delirium: treat reversible causes, non-pharmacologic measures first, haloperidol for distressing agitation.
Say the Words and Support the Family
Use 'dying' and 'died' rather than euphemisms, which are frequently misunderstood at exactly the moment clarity matters. Never say 'there is nothing more we can do': there is always more care, just not more disease-directed treatment. Document the conversation, not just the order, and involve chaplaincy, social work and bereavement support as part of the plan rather than as an afterthought.
RoundsRx Infographic Series · #116 · Oncology & Palliative · PDF 139 KB
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Palliative Care · One Pager
Palliative Care
REMAP framework for goals of care. Code status ≠ GOC. Morphine for dyspnea. Fan at face. Consult for refractory symptoms, complex GOC, family conflict.
🧪 REMAP Framework
Reframe (medical reality without jargon). Expect emotion (pause, acknowledge). Map values ("what matters most?"). Align (recommendation based on values). Plan (concrete next steps).
🚨 Symptom Management
Pain: WHO ladder (non-opioid → weak → strong opioid) + adjuvants (gabapentin, duloxetine). Dyspnea: morphine (first-line) + fan at face + O₂ if hypoxic. Nausea: ondansetron, haloperidol. Delirium: haloperidol, lorazepam.
💊 When to Consult
Refractory symptoms despite standard management. Complex goals of care conversations. Family conflict. Transition to hospice. Withdrawal of life-sustaining treatment. Existential/spiritual distress.
The treatment paradigm has shifted. It's no longer just about A1c -cardiorenal protection drives drug selection. SGLT2 inhibitors and GLP-1 agonists now have organ-protective benefits independent of glucose lowering.
💊 ADA 2026 Treatment Algorithm
What changed in ADA 2026 Standards of Care (released January 2026): (1)GLP-1 RA / dual GIP-GLP-1 (tirzepatide, semaglutide) elevated to first-line after metformin for T2DM with obesity, ahead of SU / TZD (SURMOUNT-1, 2022 · SELECT, 2023). (2)SGLT2i recommended for ALL CKD (eGFR ≥ 20, regardless of A1c) -mirrors KDIGO 2024 (DAPA-CKD, 2020 · EMPA-KIDNEY, 2023 · FIDELIO-DKD, 2020). (3)CGM expanded to T2DM on ANY basal insulin (was intensive-insulin only). (4)Screening starts age 35 for all adults; age 25 if BMI ≥ 25 + risk factors. (5)Lp(a) once per lifetime in DM (parallels 2026 ACC/AHA Dyslipidemia Guideline). (6)GLP-1 RA + SGLT2i preferred over insulin when ASCVD / HF / CKD coexist -insulin is no longer "default escalation" (LEADER, 2016 · EMPA-REG OUTCOME, 2015). (7) Inpatient: glucose target 140-180; basal-bolus over sliding-scale-only; SQ insulin acceptable for mild-moderate DKA.
Step 1 -All Type 2 DM
Metformin (Glucophage) remains first-line for most patients (A1c reduction ~1.5%, weight neutral, cheap, CV benefit UKPDS 34, 1998). Dose by eGFR ↗
Lifestyle: 150 min/week moderate exercise, 5–7% weight loss target, medical nutrition therapy DPP, 2002
A1c target: < 7% for mostDCCT, 1993 (correlates with TIR >70%). < 6.5% if early disease, no hypoglycemia risk ADVANCE, 2008. < 8% if elderly, multiple comorbidities, limited life expectancy ACCORD, 2008. ADA 2026: Older adults with complex health → TIR goal 50% (12 hrs/day); time below 70 <1% (15 min/day).
Step 2 -Add Based on Comorbidities (Not Just A1c)
Default rule: these agents are ADD-ON to metformin, not replacement. Continue metformin (mortality benefit, weight neutral, cheap, synergistic) AND layer the comorbidity-targeted agent on top. Replacement only when metformin is contraindicated -eGFR < 30, severe GI intolerance, or prior lactic acidosis. Rows tagged REPLACE below indicate metformin must come off; rows tagged REPLACE IF INTOLERANT indicate metformin stays if the patient tolerates it. Per ADA 2026, when A1c ≥ 1.5-2% above goal OR CV risk is high, you can start triple therapy on day 1 (metformin + GLP-1 RA + SGLT2i together) rather than wait for stepwise failure.
Comorbidity
Preferred Agent
Key Trial
Notes
ASCVD or high CV risk
GLP-1 RA (semaglutide, liraglutide, dulaglutide) PREFERRED
SUSTAIN-6, 2016LEADER, 2016
Reduce MACE (MI, stroke, CV death). Weight loss 5–15%. Weekly injection (semaglutide SC) or daily (liraglutide). GI side effects (nausea) limit titration. Also available PO (oral semaglutide).
Heart failure (HFrEF or HFpEF)
SGLT2i (empagliflozin, dapagliflozin) PREFERRED
EMPA-REG, 2015DAPA-HF, 2019
Reduce HF hospitalization and CV death -even in patients WITHOUT diabetes EMPEROR-Preserved, 2021. Now part of HF guideline-directed therapy. Also renal-protective.
CKD (eGFR 20–60 or albuminuria)
SGLT2i (dapagliflozin, empagliflozin) PREFERRED
DAPA-CKD, 2020EMPA-KIDNEY, 2022
Slow CKD progression by 30–40%. Can use down to eGFR 20 (initiate) or continue to dialysis. Glucose-lowering effect diminishes at low GFR but renal benefit persists.
Obesity (weight loss priority)
GLP-1 RA (semaglutide > others) or tirzepatide (dual GIP/GLP-1)
SURPASS, 2021SURMOUNT, 2022
Tirzepatide: most potent A1c reduction (~2.5%) and weight loss (~15–20%). Semaglutide 2.4 mg (Wegovy) FDA-approved for obesity regardless of DM.
MASLD / MASH (liver fibrosis in T2DM)
GLP-1 RA (semaglutide preferred) or tirzepatide ADA 2026 - 1ST LINE
ESSENCE, 2024
First-line for liver fibrosis in T2DM per ADA 2026. Pioglitazone is an alternative (also improves liver histology) but causes weight gain. Semaglutide reverses MASH fibrosis without worsening steatohepatitis. Avoid agents that worsen hepatic disease (sulfonylureas can complicate, methotrexate-like agents).
Stroke history (secondary prevention)
GLP-1 RA (semaglutide, dulaglutide)
REWIND, 2019SUSTAIN-6, 2016
GLP-1 RA reduces stroke specifically (39% in SUSTAIN-6, 24% in REWIND). Stronger anti-stroke effect than SGLT2i. Add ASA + statin per ASCVD guidelines.
A1c ≥ 10% WITH symptoms (polyuria, polydipsia, weight loss, ketones)
Insulin (often basal + metformin) URGENT
ADA 2026 algorithm
Symptomatic hyperglycemia or evidence of catabolism (DKA, ketosis, >5% weight loss) requires rapid glucose control with insulin. Start basal 0.1-0.2 units/kg, titrate every 3 days. Once stable and asymptomatic, can transition to oral agents based on comorbidities. Rule out T1DM (GAD antibodies, C-peptide).
eGFR < 30
GLP-1 RA preferred (lower hypoglycemia) REPLACE METFORMIN ADA 2026
FDA labeling, ADA 2026
Metformin contraindicated -STOP IT (lactic acidosis risk; some guidelines tolerate down to 30 with reduced dose). SGLT2i loses glucose-lowering effect < 30 but renal/CV benefit persists -continue if already on for renal protection. Sulfonylureas avoid (especially glyburide -prolonged hypoglycemia). DPP-4i (linagliptin only -hepatically cleared, no renal adjustment) and insulin are alternatives.
Metformin (if tolerated) or DPP-4i (linagliptin) REPLACE IF INTOLERANT
Geriatric guidelines
Keep metformin if the patient tolerates it; switch to linagliptin if GI side effects, anorexia, or sarcopenia/weight-loss concern. Relax A1c target to < 8% (or 8.5% if frail/dementia). Avoid SU and basal-bolus insulin (hypoglycemia risk = falls, fractures, hospitalization). DPP-4i is well-tolerated, no hypoglycemia. SGLT2i OK if no orthostasis. GLP-1 RA OK if no GI fragility / weight-loss concern.
Cost / simplicity priority
Sulfonylurea (glipizide, glimepiride) or pioglitazone COST-DRIVEN ONLY
UKPDS 1998 (no CV benefit for SU)
Why SUs are NOT first-line in most cases: (1) hypoglycemia risk -severe especially in elderly, CKD, missed meals, alcohol; glyburide is on AGS Beers Criteria. (2) Weight gain 2-3 kg -opposite of what most T2DM patients need. (3) Secondary failure within 5-10 years as β-cell function declines. (4) No CV mortality benefit (unlike metformin, GLP-1 RA, SGLT2i). (5) No renal protection. (6) Possible cardiac harm signal from K-ATP channel effects (mostly historical concern). Genuine indications where SUs ARE preferred: (a) MODY (HNF1A or HNF4A) -first-line on clinical merit, excellent response. (b) Pancreatitis history (precludes GLP-1 RA / DPP-4i). (c) Bridge while awaiting prior auth on a preferred agent. (d) Cost truly is the deciding factor (uninsured patient -SU pennies/day vs SGLT2i $300-500/mo, GLP-1 RA $800-1500/mo). Glipizide preferred over glyburide (shorter half-life, no active renal metabolites). Pioglitazone: useful in MASLD/MASH (improves liver histology), but causes fluid retention (avoid HFrEF), fracture risk in postmenopausal women, weight gain, bladder cancer concern.
The key paradigm shift: drug selection is now driven by comorbidities (ASCVD, HF, CKD, obesity), not just A1c. A patient with DM + HF should be on an SGLT2i regardless of their A1c. A patient with DM + ASCVD should be on a GLP-1 RA.
ADA 2026 Updates:
• Initial combo therapy: Start GLP-1 RA + SGLT2i together when A1c is ≥1.5–2% above goal OR high CVD risk, regardless of A1c
• GLP-1 RA in T1DM: Now recommended for adults with T1DM and BMI ≥30 (≥27.5 for Asian Americans), first time ever
• GLP-1 RA for advanced CKD: Preferred for glycemic management when eGFR <30 (lower hypoglycemia risk)
• GLP-1 RA for MASLD/MASH: First-line for liver fibrosis in T2DM
• Dual GIP/GLP-1 (tirzepatide): Added to HFpEF algorithm alongside SGLT2i
• SGLT2i + finerenone: Simultaneous initiation for UACR ≥100 mg/g with eGFR 30–90
• CGM at diagnosis: Recommended at diabetes onset for anyone who may benefit, no longer limited to insulin users
• BP target: Systolic <120 mmHg for high CV or renal risk (lowered from 130)
📋 On Rounds
Why are SGLT2 inhibitors beneficial in HF even without diabetes?
The HF benefit of SGLT2i is independent of glucose lowering. Proposed mechanisms: (1) Osmotic diuresis + natriuresis → reduces preload and congestion without RAAS activation (unlike loop diuretics). (2) Improved cardiac energetics -shifts myocardial fuel from fatty acids to ketone bodies (more efficient substrate). (3) Reduced interstitial fibrosis and inflammation. (4) Improved endothelial function.
Why are SGLT2 inhibitors given even in patients with A1c at goal?
SGLT2 inhibitors have organ-protective benefits independent of glucose lowering. EMPA-REG OUTCOME EMPA-REG, 2015 showed empagliflozin reduced CV death by 38% in T2DM with ASCVD -a benefit too large and too fast to be explained by A1c reduction alone. DAPA-CKD showed dapagliflozin slowed CKD progression even in non-diabetic kidney disease. EMPEROR-Preserved showed benefit in HFpEF.
How do you choose between GLP-1 RA and SGLT2i when a patient has both ASCVD and CKD?
Start both -they work through different mechanisms and benefits are additive. If you must prioritize one: ASCVD-dominant → GLP-1 RA first (semaglutide, liraglutide -proven CV death reduction SUSTAIN-6, LEADER). CKD-dominant → SGLT2i first (empagliflozin, dapagliflozin -proven renal protection CREDENCE, DAPA-CKD, slow eGFR decline, reduce proteinuria).
What is the 'legacy effect' in diabetes and why does early A1c matter?
The legacy effect (metabolic memory) refers to the long-term benefit of early intensive glucose control -even after control is later relaxed. UKPDS 34, 1998 initially showed modest benefit of intensive control in newly diagnosed T2DM. But the 10-year post-trial follow-up showed the intensively-treated group continued to have lower rates of MI and death even though A1c had equalized between groups.
Clinical Examples
📋 Case 1, T2DM with ASCVD: Adding GLP-1 RA
Patient: 62M with T2DM (A1c 8.2%), prior MI, BMI 31, eGFR 68. Currently on metformin 1000 mg BID. BP 138/82 on lisinopril. LDL 72 on statin.
Key findings: Established ASCVD (prior MI), requires cardiorenal protective agent regardless of A1c. Not at A1c goal despite metformin. Overweight.
Management:
Add semaglutide 0.25 mg SQ weekly → titrate to 1 mg (GLP-1 RA with proven CV benefit) SUSTAIN-6, 2016
Continue metformin (complementary mechanism, renal-safe at eGFR > 30)
A1c target < 7% for this patient (established ASCVD, reasonable life expectancy)
Counsel on GI side effects (nausea, improves with slow titration)
Recheck A1c in 3 months; if still above target, consider adding SGLT2i for additive cardiorenal benefit
Teaching point: In T2DM with ASCVD, GLP-1 RA or SGLT2i should be added independent of A1c. The CV benefit is beyond glucose lowering. ADA 2026 recommends these as first-line add-on in ASCVD.
Key findings: Triple indication for SGLT2i: T2DM + HFrEF + CKD with albuminuria. Current A1c near goal but cardiorenal protection is the primary reason to add SGLT2i.
Continue metformin (reduce to 500 mg daily if eGFR drops below 30)
Warn: initial eGFR dip of 10-15% is expected and not a reason to stop (hemodynamic, not structural)
Monitor K⁺ closely (on spironolactone + ACEi + SGLT2i)
Counsel on genital mycotic infections (candidiasis risk ~5-8%), maintain hygiene
Teaching point: SGLT2 inhibitors are now pillar therapy for HF and CKD independent of diabetes status. The initial eGFR dip is tubuloglomerular feedback, protective long-term. Do not stop for a 10-15% creatinine rise.
📋 Case 3, Newly Diagnosed T2DM with A1c > 10%
Patient: 47M newly diagnosed T2DM. A1c 11.2%, FBG 310. Polyuria, polydipsia, 15 lb weight loss over 2 months. BMI 36. No ASCVD. eGFR 92. GAD antibodies negative.
Key findings: Symptomatic hyperglycemia with A1c > 10%, indication for initial insulin therapy per ADA guidelines. GAD negative confirms T2DM (not LADA).
Management:
Start basal insulin: glargine 0.2 U/kg/day (or 10 units) at bedtime, titrate by 2 U q3 days to FBG 80-130
Start metformin 500 mg daily → titrate to 1000 mg BID over 4 weeks (GI tolerance)
Plan to add GLP-1 RA once insulin dose stabilizes (weight benefit, potential insulin de-escalation)
Recheck A1c in 3 months, once A1c < 9%, may attempt insulin taper with oral/injectable agents
Teaching point: A1c > 10% with symptoms = start insulin (oral agents alone are too slow). This is temporary, once glucose toxicity resolves, beta-cell function often partially recovers and insulin can be weaned.
📣 Sample Presentation
One-Liner
"Mrs. Patel is a 54-year-old with T2DM (A1c 8.6), BMI 34, ASCVD (prior MI), and eGFR 52, currently on metformin 1000 BID only. Here for medication optimization."
Need TWO abnormal results on different days, OR one abnormal result with classic symptoms (polyuria, polydipsia, unintentional weight loss). Any of the four criteria below qualifies.
Test
Diabetes
Prediabetes
Normal
HbA1c (NGSP-certified, DCCT-aligned)
≥ 6.5%
5.7-6.4%
< 5.7%
Fasting plasma glucose (≥ 8h fast)
≥ 126 mg/dL
100-125 mg/dL (IFG)
< 100 mg/dL
2-hour OGTT (75 g glucose load)
≥ 200 mg/dL
140-199 mg/dL (IGT)
< 140 mg/dL
Random plasma glucose
≥ 200 mg/dL WITH classic symptoms
,
,
HbA1c caveats: falsely low in conditions that shorten RBC lifespan (hemolysis, recent transfusion, hemoglobinopathies like sickle cell, pregnancy 2nd-3rd trimester, EPO therapy). Falsely high in iron deficiency anemia, splenectomy, uremia. Use fasting glucose or fructosamine when A1c is unreliable.
Screening Recommendations
USPSTF 2021: screen adults age 35-70 with overweight/obesity (BMI ≥ 25, or ≥ 23 in Asian Americans). Repeat every 3 years if normal.
ADA 2025: screen all adults age ≥ 35, OR younger if BMI ≥ 25 plus ≥ 1 risk factor. Repeat at least every 3 years.
ADA 2026 update: CGM at diagnosis recommended for anyone who may benefit -no longer limited to insulin users.
Risk factors warranting earlier / more frequent screening
Pancreatic surgery / chronic pancreatitis / cystic fibrosis / hemochromatosis; on glucocorticoids, antipsychotics, calcineurin inhibitors, thiazides; Cushing's, acromegaly, pheochromocytoma, hyperthyroidism
Workup the underlying cause. Often resolves or improves when the trigger is treated.
When to send antibodies / C-peptide: young (< 30), lean, rapid progression to insulin, atypical course (rapid β-cell failure on oral agents), DKA at presentation, or strong personal/family history of autoimmunity. GAD-65 alone catches ~70-80% of T1/LADA; add IA-2 or ZnT8 for higher sensitivity.
Initial Labs at Diagnosis
Test
Reason We Check
What It Changes
HbA1c
Confirm diagnosis + baseline for treatment response
Drives initial regimen choice. A1c > 9% → consider dual therapy or initial insulin. A1c > 10% with symptoms → likely insulin (especially if T1 not yet excluded).
BMP / eGFR
Baseline kidney function for drug dosing + screen for diabetic nephropathy
eGFR < 30: hold metformin, dose-adjust SGLT2i, avoid sulfonylureas with active metabolites (glyburide). eGFR 30-45: reduce metformin to 1000 mg/day.
UACR
Detect microalbuminuria (earliest sign of diabetic nephropathy)
UACR ≥ 30 mg/g → start ACEi/ARB even if BP is normal. UACR ≥ 100 with eGFR 30-90 → add finerenone (FIDELIO/FIGARO). Add SGLT2i (renal-protective).
ALT elevated → FIB-4 score for fibrosis stratification. ADA 2026: GLP-1 RA is first-line for liver fibrosis in T2DM.
TSH
Higher rate of autoimmune thyroid disease, especially in T1DM
Hypothyroid → levothyroxine; abnormal TSH worsens lipid profile and may complicate weight management.
Vitamin B12
Baseline (or after 4-5 years) for patients on metformin -inhibits B12 absorption
B12 deficiency → switch metformin or supplement; can mimic peripheral neuropathy.
Dilated retinal exam
Detect retinopathy at baseline
T2DM (Type 2): at diagnosis, then q1-2 years if normal. T2DM patients often have ~4-10 years of subclinical hyperglycemia before diagnosis, so 20-30% already have retinopathy at first screen. T1DM (Type 1): within 5 years of diagnosis, then annually. T1DM is diagnosed acutely so retinopathy hasn't had time to develop. Earlier referral if any retinopathy present or pregnancy planned (pregnancy can rapidly worsen retinopathy).
Foot exam (monofilament, vibration, ABI if pulses absent)
What to send only if T1 is suspected: GAD-65 antibody, IA-2 antibody, ZnT8 antibody, fasting C-peptide. Also screen for celiac disease (TTG IgA + total IgA) and autoimmune thyroid (TSH, TPO antibody) -all are associated with T1DM.
ASA for established ASCVD (secondary prevention). Shared decision in primary prevention (ASCEND 2018: small CV benefit, equal bleeding harm in DM without CVD).
Avoid routine primary-prevention ASA in DM > 70 (ASPREE 2018). Clopidogrel if true ASA allergy.
5. Weight management
5-7% weight loss for prediabetes prevention. 10-15% for diabetes remission potential. Bariatric surgery if BMI ≥ 35 + comorbidity.
GLP-1 RA (semaglutide) and tirzepatide are now disease-modifying for obesity-driven T2DM. DiRECT, 2018 showed remission possible with weight loss.
Complication Screening Schedule
Screening
When to start
Frequency
Action on abnormal
Dilated retinal exam
T2DM (Type 2): at diagnosis. T1DM (Type 1): within 5 years of diagnosis. Pregnancy: 1st trimester (or pre-conception).
q1-2 years if normal. Annually if any retinopathy. q3-6 months if proliferative or pregnant.
Refer ophthalmology. Anti-VEGF injections for DME or PDR. Tighter glycemic and BP control.
UACR + serum Cr/eGFR
T2DM: at diagnosis. T1DM: within 5 years of diagnosis. Pregnancy: pre-conception.
Annually. Confirm albuminuria with 2/3 abnormal samples within 6 months before labeling.
Higher prevalence in DM. Treat (CBT, SSRI). Worsens self-management.
B12 (if on metformin)
After 4-5 years on metformin
Periodically; sooner if neuropathy or anemia.
Replace if low. Consider switching off metformin if recurrent.
Hypoglycemia Management
Severity
Definition
Treatment
Level 1 (Alert)
BG < 70 mg/dL, patient self-treating
15-15 rule: 15 g fast-acting carbs (4 oz juice, 3-4 glucose tabs, 1 tbsp honey). Recheck in 15 minutes. Repeat if still < 70. Add complex carb + protein after corrected.
Level 2 (Clinically significant)
BG < 54 mg/dL
Same as Level 1, but evaluate regimen. Adjust meds within 24-48 h.
Level 3 (Severe)
Altered mental status / requires assistance, regardless of BG
Glucagon 1 mg IM/SC (or 3 mg intranasal, Baqsimi) at home. D50 25 g IV (1 amp) in clinic/ED. Position in recovery, call EMS. Follow with carbs once awake.
Treatment: 2-3 weeks of strict avoidance of hypoglycemia (relax A1c target temporarily) restores adrenergic awareness.
CGM with predictive low alerts is the single biggest tool for these patients.
Counsel against driving with BG < 100 in a hypo-unaware patient.
Reverse the regimen, not just the episode. Recurrent hypoglycemia signals over-medication. Common culprits: sulfonylureas (especially glyburide -has long-acting renal metabolites; avoid in CKD), insulin doses out of proportion to current weight/A1c, missed meals, alcohol on a sulfonylurea / insulin, recent renal decline (drugs accumulate). Switch off SU to a DPP-4i, GLP-1 RA, or SGLT2i if hypoglycemia is recurrent.
Sick-Day Rules (counsel every patient on insulin)
Tell every insulin-treated patient: "Don't stop your insulin even if you can't eat." Stopping insulin during illness in T1DM is the #1 outpatient cause of DKA admissions.
Continue insulin (especially basal). Adjust bolus to carbs eaten -reduce by 25-50% if eating less, but don't stop.
Check BG q3-4 h while ill. Check ketones (urine or blood β-hydroxybutyrate) if BG > 250 in T1DM.
Hydration: sip clear fluids; alternate sugar-free and sugar-containing if BG dropping.
Hold metformin if vomiting, dehydrated, or hospitalized. Resume when eating and stable.
Hold SGLT2i if NPO, severe illness, surgery within 3 days, or any GI illness with poor PO intake (euglycemic DKA risk). Resume when eating normally.
When to call provider / go to ED: persistent vomiting, BG > 300 despite correction, ketones moderate-large, AMS, RR > 24, abdominal pain, can't keep fluids down for 4+ hours.
Vaccinations Specific to DM
Influenza -annually. Higher mortality in DM with flu.
Pneumococcal -PCV20 alone, OR PCV15 followed by PPSV23 ≥ 1 year later. ACIP 2022 algorithm.
Hepatitis B -3-dose series for adults age 19-59 with DM (and shared decision ≥ 60). Higher HBV exposure risk via fingerstick equipment in shared settings.
Tdap -once, then Td or Tdap booster q10 years.
Shingrix (zoster) -2 doses for adults ≥ 50.
RSV -single dose for adults ≥ 60 with DM (CDC 2024 expanded).
DSMES referral at 4 critical times: at diagnosis, annually, when complications develop, when transitions in care occur (insulin start, pump start, pregnancy, transplant).
Medical Nutrition Therapy (MNT) with a registered dietitian -Medicare covers.
Endocrinology referral: T1DM, complex T2DM, recurrent severe hypoglycemia, hypoglycemia unawareness, considering pump or advanced CGM, A1c not at goal despite triple therapy.
Bariatric surgery referral: BMI ≥ 35 with T2DM (or BMI ≥ 30 with poor glycemic control on multiple agents). Roux-en-Y and sleeve gastrectomy both produce diabetes remission rates of 60-80% at 1 year.
Mental health referral: depression, eating disorder, diabetes distress.
💊 Medications
▶ How to Escalate Meds in Uncomplicated T2DM (tap to expand)
Scope: this ladder is for the "uncomplicated" T2DM patient, no ASCVD, no HF, no CKD, no obesity-priority, cost not the dominant factor. If any of those comorbidities are present, the ADA 2026 algorithm jumps straight to the compelling-indication agent (SGLT2i for HF/CKD, GLP-1 RA for ASCVD/obesity) regardless of A1c. Recheck A1c every 3 months at each step (RBC turnover, sooner reflects the prior regimen).
Step 1: Metformin + lifestyle
What
How
Why
Metformin
500 mg PO daily with largest meal, titrate to 1000 mg BID over 2-4 weeks
A1c drop ~1-1.5%, weight-neutral, no hypoglycemia, mortality benefit (UKPDS 34). Slow titration limits GI side effects, the #1 reason patients quit. Hold at eGFR < 30.
Lifestyle
Mediterranean or low-carb diet, 150 min/week moderate activity, 5-10% weight loss
5-10% weight loss alone drops A1c ~0.5-1%. Reinforce at every visit, never "graduates" off the plan.
Step 2 (A1c above goal at 3 months): add a second agent
ADA 2026 / EASD preference is GLP-1 RA or SGLT2i even in uncomplicated patients, because cardio-renal benefit accrues before disease is clinically apparent and both drive weight loss. Use SU, DPP-4i, or TZD only when cost or tolerance forces it.
A1c drop ~0.5-1%, modest weight loss, BP drop, cardio-renal benefit even without overt HF/CKD. Cheaper than GLP-1 RA. Watch genital mycotic infection and euglycemic DKA.
DPP-4i
Sitagliptin 100 mg, linagliptin 5 mg daily
Use if patient won't tolerate GLP-1 RA GI effects or refuses injection, and SGLT2i not tolerated. Weight-neutral, very low hypo risk, but only ~0.5-0.7% A1c. Use sitagliptin or linagliptin (HF-safe); avoid saxagliptin/alogliptin (HF signal).
Sulfonylurea
Glipizide 2.5-5 mg daily, titrate to max 20 mg/day
Cheap, ~1-1.5% A1c, but weight gain and hypoglycemia (especially in CKD, elderly, skipped meals). Only when cost dominates. Glipizide preferred over glyburide (shorter half-life, no renal active metabolites).
TZD
Pioglitazone 15-30 mg daily
Cheap, durable A1c effect ~1%, no hypoglycemia. But weight gain, edema, fracture risk (postmenopausal women), bladder cancer signal, HF caution (fluid retention, avoid in NYHA III-IV).
Step 3: combine GLP-1 RA + SGLT2i
If A1c still above goal on metformin + one second-line agent, add the other preferred class on top. The two have additive A1c effects, additive weight loss, and complementary mechanisms (incretin vs glucosuric). This triple combo handles most patients without ever needing insulin. Don't combine DPP-4i with GLP-1 RA, overlapping incretin mechanism, no added benefit, more nausea.
Step 4: add basal insulin
What
How
Why
Start basal
Glargine (Lantus/Toujeo) or degludec (Tresiba) 10 units qHS, or 0.1-0.2 U/kg
Adds A1c reduction not capped by β-cell reserve. Long-acting analogs have less nocturnal hypo than NPH.
Titrate
Increase by 2 units every 3 days until fasting glucose 80-130
Target the fasting BG, basal insulin doesn't fix postprandial spikes. "2-by-3" is the most teachable rule for residents and patients.
Keep
Continue metformin + GLP-1 RA + SGLT2i
The oral/injectable agents lower the insulin dose needed (less weight gain, less hypoglycemia, and preserves cardio-renal benefit).
Step 5: basal-bolus or co-formulated
If A1c still above goal despite well-titrated basal (fasting at target but A1c still high), the problem is now postprandial. Two options:
Add prandial rapid-acting insulin (lispro, aspart, glulisine) at the largest meal first; expand to all 3 meals if needed. Most flexible, most hypoglycemia.
Switch to a co-formulated GLP-1 RA + basal: Xultophy (degludec/liraglutide) or Soliqua (glargine/lixisenatide). One injection, GLP-1 RA component covers postprandial, simpler than basal-bolus.
Glucotoxicity itself suppresses β-cell function; reversing it with insulin often restores enough endogenous insulin to wean back to orals/GLP-1 RA within months.
Random glucose > 300 + ketonuria
Insulin and rule out T1DM/LADA (anti-GAD, C-peptide) before assuming T2DM
Adult-onset T1DM is missed often; ketosis at presentation is a red flag. Wrong diagnosis means wrong drug class and risk of DKA.
BMI > 35 or weight loss is the dominant goal
Lead with GLP-1 RA or tirzepatide (Mounjaro 2.5 → 15 mg weekly), bariatric referral if BMI > 40
Tirzepatide A1c drop ~2-2.5% and weight loss 15-20%, eclipses every other oral combination.
eGFR < 30
Avoid metformin and most SGLT2i; use linagliptin (no renal adjustment) ± GLP-1 RA ± insulin
Metformin lactic acidosis risk and SGLT2i glycemic efficacy fall off; linagliptin is hepatically cleared.
Metformin (still first-line)
Drug
Starting → Target Dose
Key Notes
Metformin (Glucophage) 1ST LINE
500 mg PO daily/BID with meals → titrate q1-2 weeks to 1000 mg BID (max 2000-2550 mg/day)
A1c reduction ~1-1.5%. Weight neutral, very cheap, mortality benefit (UKPDS 34, 1998). GI side effects (diarrhea, nausea) -titrate slowly, take with food, ER form better tolerated. B12 deficiency after 4-5 years -check B12 periodically. Lactic acidosis rare; hold at eGFR < 30, dose-reduce 30-45 to 1000 mg/day max. Hold 48 h around iodinated contrast if eGFR < 60 or AKI.
SGLT2 Inhibitors (cardiorenal protective)
Drug
Dose
Key Notes
Dapagliflozin (Farxiga) HF + CKD
10 mg PO daily (no titration)
HFrEF/HFpEF benefit (DAPA-HF, DELIVER). CKD benefit (DAPA-CKD). Initiate down to eGFR 20; continue to dialysis. A1c ~0.5-0.7%.
Empagliflozin (Jardiance) HF + CKD + ASCVD
10 mg PO daily (T2DM); titrate to 25 mg if needed for glycemia. 10 mg only for HF/CKD indication.
EMPA-REG, 2015 first to show CV benefit. EMPEROR-Reduced/Preserved/EMPA-KIDNEY all positive. Initiate to eGFR 20.
Canagliflozin (Invokana)
100 mg PO daily → 300 mg if eGFR ≥ 60
CREDENCE, 2019 showed renal protection. Black-box warning for amputation (mostly toe) and bone fracture from CANVAS -less seen with newer agents but still on label.
Ertugliflozin (Steglatro) LESS USED
5 mg PO daily → 15 mg
VERTIS-CV was non-inferior but didn't show same CV/renal benefits as the others. Reserve if cost dictates.
SGLT2i class warnings:genitourinary mycotic infections (~5-8%, candidiasis -hygiene counseling), euglycemic DKA (especially T1DM, NPO, surgery, severe illness -hold 3 days pre-op, pause during acute illness), volume depletion (especially with diuretics -reduce loop dose ~25% when starting), Fournier's gangrene (very rare but mortality > 20%, urgent surgical), initial 0.2-0.3 Cr bump (hemodynamic, reverses, do NOT stop), UTI risk modestly increased. Avoid in T1DM unless under endocrinologist guidance.
LEADER, 2016. Daily injection. Largely replaced by once-weekly options.
Dulaglutide (Trulicity)
0.75 mg SC weekly → 1.5 → 3.0 → 4.5 mg
REWIND, 2019. Easier injection device than semaglutide.
Tirzepatide (Mounjaro / Zepbound) DUAL GIP/GLP-1
2.5 mg SC weekly × 4 wk → titrate by 2.5 mg q4 wk → max 15 mg
SURPASS, 2021: A1c ~2-2.5%, weight loss 12-15 kg. SURMOUNT-1, 2022: 20% weight loss in obesity. CV outcomes pending (SURPASS-CVOT).
Exenatide ER (Bydureon BCise) LESS USED
2 mg SC weekly
Older agent. Modest A1c. Largely replaced by semaglutide/dulaglutide.
GLP-1 RA / dual agonist warnings:GI side effects are rate-limiting (nausea, vomiting, diarrhea, constipation -slow titration helps; ~15-20% discontinue), pancreatitis (rare; hold for severe abdominal pain), gallbladder disease (~1-2% incidence with rapid weight loss), retinopathy progression with rapid A1c drop (counsel + retinal exam pre-initiation in patients with known retinopathy), thyroid C-cell tumor concern (animal data only -avoid with personal/family hx of MTC or MEN2), delayed gastric emptying (pre-anesthesia hold per ASA 2023: 1 week for weekly agents, 1 day for daily). Combine with caution if insulin or sulfonylurea -reduce those doses to avoid hypoglycemia.
DPP-4 Inhibitors (modest A1c, weight neutral)
Drug
Dose
Key Notes
Sitagliptin (Januvia) HF-SAFE
100 mg PO daily (50 if eGFR 30-45; 25 if < 30)
Most-used DPP-4i. A1c ~0.5-0.7%. Weight neutral. TECOS, 2015 showed no increased HF hospitalization -preferred DPP-4i if HF history.
Linagliptin (Tradjenta) CKD-FRIENDLYHF-SAFE
5 mg PO daily (no renal adjustment)
Hepatically cleared. Useful when eGFR fluctuates or CKD limits other choices. CARMELINA, 2018 confirmed no HF hospitalization signal -safe choice in HF + CKD.
Saxagliptin (Onglyza) HF SIGNAL
5 mg PO daily (2.5 if eGFR < 45)
SAVOR-TIMI 53, 2013 showed increased HF hospitalization. Avoid if HFrEF; switch to sitagliptin or linagliptin.
Alogliptin (Nesina)
25 mg PO daily (12.5 if eGFR 30-60; 6.25 if < 30)
Less commonly used; similar profile to sitagliptin.
DPP-4i warnings: pancreatitis (rare), severe joint pain (FDA warning 2015 -reversible on discontinuation), bullous pemphigoid (rare). Don't combine DPP-4i with GLP-1 RA (overlapping mechanism, no added benefit, more nausea).
Sulfonylureas (cheap, but hypoglycemia risk)
Drug
Dose
Key Notes
Glipizide (Glucotrol) PREFERRED SU
2.5-5 mg PO daily → max 20 mg/day (split BID if > 15)
Shorter half-life and no active renal metabolites -preferred SU in CKD or elderly. A1c ~1-1.5%. Cheap. Weight gain ~2 kg.
Glimepiride (Amaryl)
1-2 mg PO daily → max 8 mg
Once-daily, modest hypoglycemia risk. OK in mild CKD; cautious if eGFR < 30.
Glyburide (Diabeta) AVOID IN CKD / ELDERLY
2.5-5 mg PO daily → max 20 mg
Avoid: long half-life and active metabolites cleared renally → severe prolonged hypoglycemia in CKD or elderly. AGS Beers Criteria flags it explicitly.
SU pearls: rapid A1c drop (1-1.5%) but secondary failure within 5-10 years as β-cell function declines. Hypoglycemia is the limiting toxicity -especially in patients on insulin, with skipped meals, alcohol, or declining renal function. Hold or reduce dose if patient becomes NPO. Largely replaced by SGLT2i and GLP-1 RA in modern algorithms.
Insulin (when oral agents aren't enough or for T1DM)
Insulin
Onset / Peak / Duration
Role
Glargine U-100 (Lantus, Basaglar) BASAL
1-2 h / no peak / 20-24 h
Once-daily basal. Most commonly used. Less hypoglycemia than NPH.
Glargine U-300 (Toujeo)
6 h / no peak / 30-36 h
Flatter profile than U-100. Less nocturnal hypoglycemia.
Detemir (Levemir)
1-2 h / mild peak 6-8 h / 12-24 h
Often needs BID dosing. Less popular than glargine.
Take 15 min before meal. Standard mealtime insulins. Lispro U-200 / Aspart fast-acting (Fiasp) are concentrated/faster variants.
Inhaled insulin (Afrezza)
~5 min / 30 min / 1.5-3 h
Niche use. Required PFTs (avoid in COPD/asthma). Bronchospasm risk.
Pre-mixed (rarely used in modern practice)
70/30, 75/25, 50/50
Combined
Two daily injections. Less flexible than basal-bolus. Used for adherence-limited patients.
Insulin initiation in T2DM (when to start)
A1c ≥ 10% with symptoms at diagnosis -consider insulin initially (often with metformin).
BG ≥ 300 with ketones or DKA features -start insulin urgently.
A1c not at goal on triple therapy (metformin + SGLT2i/GLP-1 + third agent).
Pregnancy -insulin is the agent of choice.
Hospitalized / acute illness -insulin (basal-bolus or sliding scale).
Starting basal insulin (the simplest first step)
Start 10 units bedtime OR 0.1-0.2 units/kg daily (glargine, degludec, or detemir).
Titrate by 2 units q3 days until fasting BG < 130 (or per regimen).
Continue metformin and other oral agents (especially SGLT2i and GLP-1 RA -synergistic with insulin).
Hypoglycemia < 70 once → reduce by 10-20%. Severe hypoglycemia → reduce by 20-30% and reassess.
Adding bolus insulin (basal-bolus regimen)
Start when basal alone insufficient and PP glucose elevated.
Total daily dose (TDD): 0.4-0.6 units/kg in T2DM (less in T1DM, more in steroid-induced DM).
50/50 rule: half TDD as basal (once-daily long-acting), half divided across 3 meals as bolus.
Carb counting: insulin-to-carb ratio (ICR) starts at 1 unit per 10-15 g carbs; correction factor (CF / ISF) starts at 1 unit per 50 mg/dL above target.
Refer to endocrinology / CDE for pump or hybrid closed-loop systems if multiple injections aren't controlling.
Less Common / Niche Agents
Drug
Dose
When Used
Pioglitazone (Actos)
15-45 mg PO daily
A1c ~1-1.5%. Useful in NAFLD/MASH and insulin resistance. Avoid: HFrEF (fluid retention), bladder cancer history (PROactive signal), high fracture risk (postmenopausal women). Causes weight gain ~3-5 kg.
Acarbose (Precose) / Miglitol (Glyset) RARELY USED
25-100 mg PO TID with first bite of meal
α-glucosidase inhibitors -delay carb absorption. Modest A1c (~0.5%). Severe flatulence/diarrhea limits use. Cheap but rarely tolerated.
Bromocriptine quick-release (Cycloset) RARELY USED
Bile acid sequestrant. Modest A1c (~0.5%). Bonus LDL reduction. Constipation. Can interfere with absorption of other drugs (separate by 4 h).
Pramlintide (Symlin) NICHE
15-60 mcg SC pre-meals (T1) / 60-120 mcg (T2)
Amylin analog, used as adjunct to insulin to control PP glucose and weight. Severe hypoglycemia if not paired with reduced bolus insulin.
Finerenone (Kerendia) CKD ADJUNCT
10 mg PO daily (eGFR 25-60); 20 mg if K⁺ stable
Non-steroidal MRA. Not a glycemic agent but reduces CV + renal events in DM with CKD on top of ACEi/ARB + SGLT2i. FIDELIO-DKD, 2020 + FIGARO-DKD, 2021. Watch K⁺ and eGFR.
Drugs to AVOID or use with caution in DM
Glucocorticoids -drive hyperglycemia (especially PP). Adjust insulin and BBG monitoring during courses.
Atypical antipsychotics (olanzapine, clozapine, quetiapine) -metabolic syndrome, weight gain, can precipitate DM. Use aripiprazole or lurasidone if equivalent.
Thiazides at high dose -worsen glycemic control (modestly). Low dose (12.5-25 mg HCTZ or chlorthalidone) is fine.
Statins -small absolute increase in DM diagnosis (~9% relative; ~1 case per 1000 patient-years), but CV benefit far outweighs. Continue.
β-blockers -mask hypoglycemia symptoms (especially atenolol). Use with caution in insulin-treated patients with hypoglycemia unawareness.
Niacin at high doses -worsens glycemia, often discontinued in DM.
Saxagliptin and alogliptin (DPP-4i) -avoid in HFrEF; saxagliptin showed increased HF hospitalization in SAVOR-TIMI 53 (2013) and alogliptin had a similar signal in EXAMINE (2013). Not a class effect -sitagliptin (TECOS, 2015) and linagliptin (CARMELINA, 2018) are HF-safe and remain appropriate choices.
Glyburide -avoid in CKD and elderly (renal active metabolites, prolonged hypoglycemia).
⚡ Summary
Summary
The Paradigm Has Shifted From A1c to Organ Protection
Drug selection is now driven by cardiorenal comorbidity, not by glucose alone.SGLT2 inhibitors and GLP-1 agonists have cardiovascular and renal benefits independent of their glucose lowering, so a patient with heart failure or CKD gets one regardless of how close the A1c already is to target.
Metformin Plus a Comorbidity-Driven Agent
Metformin remains first line for most, with lifestyle intervention throughout.Then add by comorbidity: ASCVD → GLP-1 agonist with proven benefit, or SGLT2 inhibitor. Heart failure → SGLT2 inhibitor. CKD → SGLT2 inhibitor, with finerenone in albuminuric diabetic kidney disease. Obesity → GLP-1 or dual agonist.
Individualize the A1c Target
Below 7% for most, tighter (6.5%) in the young with long life expectancy and no hypoglycemia risk, and looser (8% or above) in the elderly, in those with limited life expectancy, established complications, or hypoglycemia unawareness.Tight control in a frail elderly patient causes more harm than benefit, because the hypoglycemia risk is immediate while the microvascular benefit takes a decade.
Do Not Use Sulfonylureas Reflexively
They cause hypoglycemia and weight gain and have no cardiorenal benefit, and glyburide is particularly dangerous in the elderly and in renal impairment. They remain reasonable where cost is the binding constraint, which should be an explicit decision rather than a default.
Know the Renal Cutoffs
Metformin: continue to eGFR 30, do not start below 45, and hold during acute illness, contrast and hypoperfusion.SGLT2 inhibitors: continue for renal protection well below the glycemic efficacy threshold, since the benefit persists even when the glucose effect fades. Adjust or avoid others by eGFR, and re-check the list whenever renal function changes.
Give Sick-Day Rules to Everyone
Hold metformin, SGLT2 inhibitors, ACE inhibitors, ARBs and diuretics during vomiting, diarrhea or dehydration.Never stop insulin in type 1 diabetes, even when not eating.Warn SGLT2 inhibitor users about euglycemic DKA, where the glucose can be normal while the patient is acidotic, and tell them to seek care for nausea and malaise rather than assuming it is a virus.
Screen the Complications on a Schedule
Annual dilated retinal examination, annual urine albumin-to-creatinine ratio with eGFR, annual foot examination with monofilament testing, and lipid and blood pressure review.These are what actually prevent blindness, dialysis and amputation, and they are missed far more often than the A1c.
Treat the Whole Cardiovascular Bundle
Statin for essentially every diabetic over 40, blood pressure control, ACE inhibitor or ARB for albuminuria, smoking cessation, and aspirin only for secondary prevention.The macrovascular risk is reduced far more by the statin and the blood pressure than by the glucose. Add vaccination, including pneumococcal and hepatitis B, and consider CGM, which improves control in insulin-treated patients.
RoundsRx Infographic Series · #157 · Renal & Metabolic · PDF 147 KB
Text version
AMBULATORY · One Pager
Outpatient Diabetes Management
Drug selection is driven by comorbidities (ASCVD, HF, CKD, obesity), not just A1c: a patient with T2DM and HF belongs on an SGLT2i whatever their A1c reads.
🧪 Diagnosis & A1c Targets
Diagnose: A1c ≥ 6.5%, FPG ≥ 126, 2-h OGTT ≥ 200, or random ≥ 200 with classic symptoms. Need two abnormal results on different days, or one plus classic symptoms, because a single value can be assay or stress artifact.
A1c < 7% for mostDCCT, 1993, correlates with TIR > 70%. This is the threshold where microvascular benefit accrues.
< 6.5% if early disease, young, no hypoglycemia risk ADVANCE, 2008, since the downside of tight control is low when life expectancy is long.
< 8% if established CVD, advanced complications, or hypoglycemia-prone ACCORD, 2008: pushing below 6.5% here increased mortality 22%. < 8.5% if frail elderly or dementia.
Screen all adults age ≥ 35 (ADA), or younger if BMI ≥ 25 plus ≥ 1 risk factor; repeat q3 years, because T2DM runs subclinical for years before symptoms.
A1c is unreliable when RBC lifespan is short (hemolysis, transfusion, hemoglobinopathy, pregnancy 2nd-3rd trimester, EPO) which reads falsely low, or in iron deficiency, splenectomy, uremia which reads falsely high. Use FPG or fructosamine instead.
Send GAD-65 ± C-peptide if young (< 30), lean, DKA at presentation, or rapid failure of oral agents: missing LADA or T1DM means the wrong drug class and a DKA risk.
⚡ What Changed in ADA 2026
GLP-1 RA / dual GIP-GLP-1 elevated to first-line after metformin in T2DM with obesity, ahead of SU and TZD SURMOUNT-1, 2022SELECT, 2023.
SGLT2i for ALL CKD (eGFR ≥ 20, regardless of A1c), mirroring KDIGO 2024, because the renal benefit is independent of glucose lowering.
GLP-1 RA + SGLT2i preferred over insulin when ASCVD, HF, or CKD coexist. Insulin is no longer the default escalation.
Initial combination on day 1 when A1c is ≥ 1.5-2% above goal or CV risk is high: a single agent cannot close that gap and waiting wastes β-cells.
CGM at diagnosis for anyone who may benefit, no longer restricted to insulin users.
BP target systolic < 120 for high CV or renal risk, lowered from 130.
GLP-1 RA first-line for MASLD/MASH liver fibrosis in T2DM ESSENCE, 2024; and GLP-1 RA in T1DM with BMI ≥ 30 (≥ 27.5 in Asian Americans) for the first time.
Lp(a) once per lifetime in diabetes, paralleling the 2026 ACC/AHA dyslipidemia guideline.
🚨 Step 2: Pick the Add-On by Comorbidity, Not by A1c
Default rule, these are ADD-ON to metformin, not replacement. Keep metformin (mortality benefit, weight neutral, cheap, synergistic) and layer the comorbidity-targeted agent on top. Replace only when metformin is contraindicated: eGFR < 30, severe GI intolerance, or prior lactic acidosis.
ASCVD or high CV risk → GLP-1 RA (semaglutide, liraglutide, dulaglutide). Reduces MACE, meaning MI, stroke, CV death SUSTAIN-6, 2016LEADER, 2016, plus 5-15% weight loss. GI nausea rate-limits titration.
Heart failure, HFrEF or HFpEF → SGLT2i (empagliflozin, dapagliflozin). Reduces HF hospitalization and CV death even in patients without diabetes DAPA-HF, 2019EMPEROR-Preserved, 2021, so it is now guideline-directed HF therapy in its own right.
CKD, eGFR 20-60 or albuminuria → SGLT2i (dapagliflozin, empagliflozin). Slows CKD progression 30-40% DAPA-CKD, 2020EMPA-KIDNEY, 2022. Initiate down to eGFR 20 and continue to dialysis: the glucose-lowering effect fades at low GFR but the renal benefit persists.
Obesity is the priority → GLP-1 RA (semaglutide) or tirzepatide. Tirzepatide gives the most potent A1c reduction (~2.5%) and weight loss (~15-20%), which is disease-modifying in obesity-driven T2DM rather than merely glucose-lowering.
MASLD / MASH → GLP-1 RA (semaglutide preferred), ADA 2026 first-line for liver fibrosis in T2DM. Pioglitazone also improves liver histology but causes weight gain.
Prior stroke → GLP-1 RA. The anti-stroke effect is specific and stronger than SGLT2i (non-fatal stroke down 39% in SUSTAIN-6, 2016, 24% in REWIND, 2019). Add ASA plus statin per ASCVD guidelines.
A1c ≥ 10% WITH symptoms (polyuria, polydipsia, weight loss, ketones) → insulin urgently. Catabolism means oral agents are too slow: start basal 0.1-0.2 units/kg, titrate every 3 days, and rule out T1DM (GAD antibodies, C-peptide). Transition to orals once asymptomatic, since reversing glucotoxicity often restores β-cell function.
eGFR < 30 → STOP metformin (lactic acidosis risk) and use GLP-1 RA preferentially for its low hypoglycemia risk. SGLT2i loses glucose-lowering effect here but keep it if already on for renal protection. Avoid sulfonylureas, especially glyburide. Linagliptin (hepatically cleared, no renal adjustment) and insulin are the alternatives.
Older adult / frail → keep metformin if tolerated, switch to linagliptin only if GI intolerance, anorexia, or sarcopenia concern. Relax A1c to < 8% (8.5% if frail or demented) and avoid SU and basal-bolus insulin, because hypoglycemia here means falls, fractures, and hospitalization.
Cost is genuinely the deciding factor → sulfonylurea (glipizide) or pioglitazone.Why SUs are not first-line: hypoglycemia (glyburide is on AGS Beers Criteria), weight gain 2-3 kg, secondary failure within 5-10 years as β-cell function declines, no CV mortality benefit, and no renal protection. Where SUs genuinely win: MODY (HNF1A / HNF4A) on clinical merit, pancreatitis history that precludes incretins, bridging a prior authorization, or an uninsured patient (SU pennies/day vs SGLT2i $300-500/mo, GLP-1 RA $800-1500/mo).
💊 Key Drugs
Metformin (Glucophage)500 mg PO daily with the largest meal, titrate q1-2 wk to 1000 mg BID (max 2000-2550 mg/day). Slow titration limits the GI effects that are the #1 reason patients quit. Hold at eGFR < 30; reduce to 1000 mg/day at eGFR 30-45.
Semaglutide SC (Ozempic)0.25 mg SC weekly × 4 wk → 0.5 → 1.0 → 2.0 mg. Strongest A1c drop in class (~1.5-2%). The 4-week steps exist to let nausea settle.
Empagliflozin (Jardiance)10 mg PO daily; titrate to 25 mg only if more glycemia is needed. 10 mg is the dose for the HF/CKD indication, since the outcome trials used it.
Dapagliflozin (Farxiga)10 mg PO daily, no titration. Initiate down to eGFR 20 and continue to dialysis.
Tirzepatide (Mounjaro)2.5 mg SC weekly × 4 wk, then +2.5 mg q4 wk to max 15 mg. A1c ~2-2.5%, weight loss 12-15 kg, the biggest of any agent.
Linagliptin (Tradjenta)5 mg PO daily, no renal adjustment (hepatically cleared), which is why it is the DPP-4i of choice when eGFR fluctuates.
Glargine or degludec (basal)10 units qHS or 0.1-0.2 U/kg, increase 2 units q3 days to fasting glucose 80-130. Target the fasting number, because basal insulin does not fix postprandial spikes.
Finerenone (Kerendia)10 mg PO daily at eGFR 25-60, 20 mg if K⁺ stable. Not a glycemic agent: it cuts CV and renal events on top of ACEi/ARB plus SGLT2i.
📊 Monitoring & Screening
A1c q3 months while titrating: RBC turnover means anything sooner still reflects the prior regimen.
Dilated retinal exam: T2DM at diagnosis (20-30% already have retinopathy from 4-10 years of subclinical hyperglycemia), T1DM within 5 years of diagnosis; then q1-2 years if normal, annually if any retinopathy.
UACR + eGFR annually. UACR ≥ 30 → start ACEi/ARB even if BP is normal; UACR ≥ 100 with eGFR 30-90 → add finerenone. Confirm with 2 of 3 abnormal samples before labeling.
Foot exam: comprehensive annually (monofilament, vibration, pulses), visual inspection every visit, because loss of protective sensation plus deformity is the amputation pathway.
B12 after 4-5 years on metformin, which blocks B12 absorption and can mimic diabetic peripheral neuropathy.
After starting an SGLT2i: expect a 0.2-0.3 Cr bump (10-15% eGFR dip). It is hemodynamic tubuloglomerular feedback, reverses, and is protective long-term: do NOT stop for it.
CGM targets: TIR (70-180) > 70%, time below 70 < 4%, time above 180 < 25%, CV < 36%. In frail older adults TIR > 50% with time below 70 under 1% (about 15 min/day) is the safer goal.
BP every visit, lipids annually. Most CV deaths in diabetes come from BP, lipids, and unaddressed CKD, not from glucose.
⚠️ Pitfalls
Stopping the SGLT2i for the initial eGFR dip. A 10-15% creatinine rise is expected and hemodynamic, not structural injury.
Euglycemic DKA on SGLT2i. Hold 3 days before surgery and pause during NPO status, severe illness, or any GI illness with poor intake, because glucose may look normal while ketones climb.
Letting a sick insulin-treated patient stop insulin. This is the #1 outpatient cause of DKA admissions in T1DM. Reduce bolus 25-50% if eating less, but never stop basal.
Glyburide in CKD or the elderly. Renally cleared active metabolites cause prolonged severe hypoglycemia; use glipizide instead (shorter half-life, no active renal metabolites).
Saxagliptin or alogliptin in HFrEF (HF hospitalization signal). This is NOT a class effect: sitagliptin TECOS, 2015 and linagliptin CARMELINA, 2018 are HF-safe.
Combining a DPP-4i with a GLP-1 RA. Overlapping incretin mechanism means no added benefit and more nausea.
Recurrent hypoglycemia treated as an event, not a regimen problem. Reverse the regimen: usual culprits are sulfonylureas, insulin doses out of proportion to current weight, missed meals, alcohol, and recent renal decline causing drug accumulation.
Forgetting the pre-anesthesia GLP-1 hold (ASA 2023: 1 week for weekly agents, 1 day for daily) given delayed gastric emptying and aspiration risk.
🏥 Escalate / Refer When
ED or urgent call: persistent vomiting, BG > 300 despite correction, moderate-to-large ketones, altered mental status, RR > 24, abdominal pain, or unable to keep fluids down for 4+ hours. These are the DKA/HHS tripwires.
Level 3 hypoglycemia (altered mental status or needs assistance, whatever the number): glucagon 1 mg IM/SC or 3 mg intranasal at home, D50 25 g IV in clinic, then carbs once awake and a same-week regimen change.
Endocrinology: T1DM, recurrent severe hypoglycemia, hypoglycemia unawareness, pump or advanced CGM candidacy, or A1c off goal despite triple therapy.
Bariatric surgery: BMI ≥ 35 with T2DM, or BMI ≥ 30 with poor control on multiple agents. Roux-en-Y and sleeve both give 60-80% diabetes remission at 1 year.
DSMES at the 4 critical times: at diagnosis, annually, when complications develop, and at care transitions (insulin start, pump, pregnancy, transplant), because these are the moments self-management actually breaks down.
Hypoglycemia unawareness: 2-3 weeks of strict hypoglycemia avoidance (temporarily relax the A1c target) restores adrenergic warning symptoms; CGM with predictive low alerts is the single biggest tool.
🎓 Key Evidence
UKPDS 34, 1998: metformin cut all-cause mortality 36% despite similar A1c to SU/insulin, which is why metformin stayed first-line and SUs did not.
EMPA-REG OUTCOME, 2015: first SGLT2i CV outcome trial, and the benefit was too large and too fast to be explained by A1c lowering.
LEADER, 2016 and SUSTAIN-6, 2016: established GLP-1 RA as the cardioprotective class in ASCVD.
DAPA-CKD, 2020: SGLT2i became standard of care in CKD with or without diabetes.
ACCORD, 2008: the reason A1c targets are relaxed, not tightened, in high-risk patients.
DiRECT, 2018: remission is achievable with weight loss, which reframes obesity treatment as diabetes treatment.
Legacy effect: the 10-year post-trial UKPDS follow-up showed lower MI and death in the intensively treated group even after A1c had equalized. Treat early and hard; relax later.
Obesity, type 2 diabetes, chronic kidney disease and cardiovascular disease are not four problems in four clinics. The 2026 guideline stages them as one syndrome, and the stage decides what you screen for, how often, and which drug you reach for first.
🧭 Staging
What this guideline is, and what it replaced. The 2026 AHA/ACC/ADA/ASN CKM Syndrome Guideline (JACC, June 9, 2026) is the first clinical practice guideline on CKM syndrome from the ACC and AHA. It retires and replaces the 2013 AHA/ACC/TOS obesity guidelineNEW 2026. The argument is that treating obesity, T2DM, CKD and CVD as separate problems misses the fact that each one accelerates the others, so the guideline gives you a single staging system and hangs screening intervals and drug choice off the stage. Staging is recommended for youths under 18 as well as adults, because the point is to intervene before stage progression rather than after.
The Five Stages
Stage
Definition
What it changes for you
Stage 0
No CKM risk factors. Normal weight, glucose, blood pressure, lipids and kidney function, with no subclinical or clinical CVD
The goal is keeping them here. Screening is the widest-interval tier, and lifestyle counseling is the whole intervention
Stage 1
Excess or dysfunctional adiposity: overweight or obesity, abdominal obesity, or dysfunctional adipose tissue, which may include prediabetes, without the metabolic risk factors of Stage 2 and without subclinical CVD
This is the first actionable stage and the one most often ignored, because the patient feels well. Weight loss here can drive true stage regression, which is the guideline's central optimistic claim
Stage 2
Metabolic risk factors or moderate-to-high-risk CKD: hypertension, T2DM, hypertriglyceridemia, metabolic syndrome, or CKD in the moderate-to-high-risk KDIGO categories
The screening tier tightens sharply here (annual lipids, glycemia, BP, and both eGFR and UACR), and it is the entry point for cardioprotective drug therapy
Stage 3
Subclinical CVD, or a risk equivalent. Subclinical coronary disease (CAC score above 100), subclinical heart failure (NT-proBNP ≥ 125 pg/mL with echo evidence of ventricular dysfunction, or elevated high-sensitivity troponin), very high-risk CKD (stage 4 to 5, or by KDIGO heat map), or a predicted 10-year CVD risk ≥ 20% by PREVENT
Treat as the last stop before clinical disease. In Stage 3 driven by pre-HF, intensive lifestyle plus intensive risk factor control is Class 1, because progression to clinical HF is still preventable at this point
Stage 4
Clinical CVD (coronary heart disease, heart failure, stroke, peripheral artery disease, atrial fibrillation) overlapping with CKM risk factors. Subdivided into 4a without kidney failure and 4b with kidney failure
The CKM framing still changes management: the guideline's message is that treating the coronary disease while ignoring the obesity, diabetes and albuminuria leaves most of the modifiable risk on the table
Why staging rather than another risk score: the stages are explicitly bidirectional. The guideline recommends staging in order to prevent progression and to promote regression through lifestyle change and weight loss. That is the practical difference from a risk calculator, which tells you a probability but implies nothing can be undone. It also lets you match the intensity of therapy to absolute risk and expected net benefit instead of treating every risk factor with equal force.
🔬 Screening
Screening Intensity Is Set by Stage
Reading the COR tags: COR is the Class of Recommendation, the ACC/AHA scale for how strongly a recommendation is backed. COR 1 means do it: benefit far outweighs risk, and the guideline words it "is recommended". COR 2a means it is reasonable: benefit still outweighs risk, worded "can be useful", so it is a judgment call rather than a default. COR 2b is weaker again ("may be considered"), and COR 3 means do not do it, either for no benefit or for harm. The tags earn their place here because this guideline mixes strengths: annual lipids, glycemia, blood pressure and eGFR with UACR are all COR 1, while pre-HF biomarker screening is only COR 2a, so the first set is expected of you and the second is a defensible choice you should be able to justify.
What to check
Who and how often
Why this interval
BMI and waist circumference
Both, in every adult. Obesity at BMI ≥ 30 kg/m²; abdominal obesity at waist ≥ 88 cm in women, ≥ 102 cm in men
BMI alone misclassifies people: it misses the normal-BMI patient with central adiposity who carries the metabolic risk, and it overcalls the muscular patient. The guideline wants both numbers, which is the change from BMI-only practice
Lipids, glycemia, blood pressure
At least annually from Stage 2 upwardCOR 1
Stage 2 means the metabolic risk factors are already present, so the question is no longer whether they will appear but how fast they are progressing and whether treatment is working
eGFR and UACR together
Both, at least annually from Stage 2 upwardCOR 1. UACR is added once the patient is Stage 2 or above
eGFR alone misses early kidney disease, because albuminuria appears first and independently predicts both kidney and cardiovascular events. You also cannot apply the drug thresholds below without a UACR, since they are written in mg/g
PREVENT risk
Stages 0 to 3, estimating 10-year and 30-year risk of ASCVD, heart failure and total CVD. Open the PREVENT calculator
Two thresholds do real work: ≥ 20% predicted 10-year CVD risk is by itself a Stage 3 criterion, and ≥ 7.5% prioritizes starting cardioprotective drug therapy. The same calculator now serves this guideline and the 2026 dyslipidemia guideline
Pre-heart-failure biomarkers
Adults with PREVENT-HF 10-year risk ≥ 5%: check natriuretic peptides (BNP or NT-proBNP) and high-sensitivity troponin COR 2a
It identifies the patient with structural or biochemical heart disease before symptoms, which is the window where intensive risk factor control still prevents clinical HF. A positive result moves the patient to Stage 3 and justifies cardiac imaging. How to interpret BNP vs NT-proBNP ↗
FIB-4 index for liver fibrosis
CKM syndrome plus diabetes or ≥ 2 cardiometabolic risk factors: every 1 to 2 yearsCOR 1
MASLD travels with this syndrome and is usually silent. FIB-4 is calculated from age, AST, ALT and platelets, so it costs nothing extra, and it identifies who needs hepatology referral before cirrhosis
Obstructive sleep apnea
Selected patients, based on symptoms and risk
Untreated OSA drives resistant hypertension and atrial fibrillation, so it is a reversible contributor sitting inside the same syndrome
Social determinants of health
Routinely, in everyone
The guideline treats this as clinical data, not paperwork: food insecurity, housing instability and cost barriers predict both the development of CKM syndrome and failure of the treatment plan you are about to write. Prescribing a GLP-1 the patient cannot afford is a failed prescription
💊 Management
How to read this section. The drug-level detail (doses, titration, side effects, renal adjustment) lives in the dedicated topics and is deep-linked below rather than repeated here. What this page owns is the routing question: given this patient's stage and their UACR and eGFR, which agent is indicated and at what threshold. Those thresholds are where the 2026 guideline is most specific, and where it is easiest to get wrong.
Obesity: the Entry Point for the Whole Syndrome
Lifestyle modification is first-line, targeting at least 5% to 10% of baseline weightCOR 1. That range is not arbitrary: it is where metabolic benefit reliably appears (blood pressure, glycemia, triglycerides, hepatic steatosis) even when the patient remains in the obese BMI range.
Counsel about the benefits of 5% to 10% weight loss at least annuallyCOR 1, because the guideline treats the conversation itself as the intervention that gets missed.
Add obesity pharmacotherapy and metabolic or bariatric surgery as needed to reach that target. Weight loss is framed as the main lever for stage regression, not just risk factor control. Obesity and GLP-1 agents topic ↗
Type 2 Diabetes: Drug Choice Follows Risk, Not Just A1c
Recommendation
Threshold
COR
Why
SGLT2 inhibitor or GLP-1-based therapy with proven benefit
CKM Stage 2 to 3 with T2DM and 10-year PREVENT-CVD ≥ 7.5%
1
These reduce cardiovascular events and mortality through mechanisms largely independent of glucose lowering, which is why the trigger is cardiovascular risk rather than A1c
Intensified multifactorial treatment targeting hyperglycemia, hypertension, dyslipidemia and albuminuria together
CKM Stage 2 to 3 with T2DM
1
Treating the risk factors as a bundle beats sequential single-target care for CVD, mortality and kidney complications
Metformin, added to a cardioprotective agent
A1c 0.5% to 1% above the individualized goal
2a
Note the reversal from older practice: metformin is now positioned as the agent you add for glycemic control after the cardioprotective drug, rather than the mandatory first step before it
Combination GLP-1-based therapy plus SGLT2 inhibitor
Increased CVD risk or multiple CKM risk factors
2b
May add cardiovascular benefit beyond either agent alone, but the weaker class reflects that the dedicated combination outcome data are still thin
Choice between SGLT2i and GLP-1 is guided by the comorbidity mix: CKD, ASCVD, heart failure, obesity, severe hyperglycemia and MASLD each pull the decision. Outpatient diabetes topic ↗
Chronic Kidney Disease: Four Thresholds Worth Memorizing
Agent
Who qualifies
COR
Why / what it prevents
RAS inhibitor (ACEi or ARB) at the maximum tolerated dose
CKD with T2DM, or CKD without T2DM but UACR ≥ 30 mg/g, and eGFR ≥ 30
1
Reduces intraglomerular pressure and slows loss of kidney function while lowering CVD risk. Maximum tolerated dose is the recommendation, not a token dose, which is the step most often left undone
SGLT2 inhibitor
CKD with T2DM, or CKD without T2DM but UACR ≥ 200 mg/g, and eGFR ≥ 20
1
Slows loss of kidney function and lowers HF hospitalization and CV mortality DAPA-CKD, 2020EMPA-KIDNEY, 2023. Expect an early dip in eGFR and do not stop for it, it is hemodynamic and precedes the long-term benefit
SGLT2 inhibitor (weaker indication)
CKD without T2DM with UACR 30 to 199 mg/g
2a
Fills the gap below the Class 1 albuminuria threshold, where benefit is likely but the trial evidence is less direct
Nonsteroidal MRA (finerenone)
CKD + T2DM + UACR ≥ 30 mg/g despite ACEi/ARB and SGLT2i as tolerated, with eGFR ≥ 25
1
Targets the residual albuminuria that persists on standard therapy FIDELIO-DKD, 2020. Note it is an add-on, not a substitute: the qualifying condition is persistent albuminuria while already on the first two agents. Monitor potassium
GLP-1-based therapy with proven kidney benefit
CKD + T2DM + UACR ≥ 100 mg/g despite ACEi/ARB and SGLT2i as tolerated
1
The newest of the four, reducing loss of kidney function and kidney failure as well as CVD risk FLOW, 2024. The threshold is higher than the finerenone one (100 vs 30 mg/g), so read the UACR before choosing between them
CKD topic, including renal dose adjustment ↗
When CVD Is Already Present (Stage 4)
HFrEF: the CKM framing reinforces RAS inhibition (ARNI, ACEi or ARB) plus an SGLT2 inhibitor as part of quadruple therapy with a beta blocker and a steroidal MRA, chosen for their combined cardiovascular and kidney benefit. Chronic HF GDMT topic ↗
HFmrEF and HFpEF:SGLT2 inhibitor is first-line GDMT.Add a GLP-1-based therapy when obesity or other CKM risk factors are present, and consider a nonsteroidal MRA in those with T2DM and CKD.
ASCVD: management should explicitly include the CKM comorbidities, treating obesity with lifestyle, pharmacotherapy and surgery where appropriate, using cardioprotective antihyperglycemics for T2DM, and using kidney-protective agents for CKD. The failure mode this targets is the well-stented patient whose obesity, albuminuria and diabetes go unaddressed.
Interdisciplinary care with a named point person is recommended once T2DM, CKD and CVD overlap, because the predictable failure in this population is not a missing recommendation but nobody owning the plan across cardiology, nephrology, endocrinology and primary care.
🎯 Rounds
Pimp Questions
What does CKM staging add that a risk calculator does not?
Direction. The stages are explicitly bidirectional, so the guideline recommends staging to prevent progression and to promote regression through weight loss and lifestyle change. A risk score gives a probability and implies nothing can be undone. Staging also matches treatment intensity to absolute risk and expected net benefit.
A patient has a PREVENT 10-year CVD risk of 24% with no known CVD. What CKM stage is that, and why?
Stage 3. A predicted 10-year CVD risk of at least 20% is by itself a Stage 3 criterion, even without imaging or biomarker evidence of subclinical disease. The separate 7.5% threshold is what prioritizes starting an SGLT2 inhibitor or GLP-1-based therapy in a patient with T2DM.
Why does the guideline insist on both eGFR and UACR rather than eGFR alone?
eGFR alone misses early disease. Albuminuria appears first and independently predicts kidney and cardiovascular events. Practically, every CKD drug threshold in the guideline is written in mg/g of UACR, so without it you cannot tell whether the patient qualifies for an SGLT2 inhibitor, finerenone, or a GLP-1.
T2DM, CKD, UACR 60 mg/g, eGFR 40, already on a maximally tolerated ARB and an SGLT2 inhibitor. What is next and why?
Add a nonsteroidal MRA such as finerenone (Class 1): the patient has T2DM with CKD and persistent UACR of at least 30 mg/g despite the first two agents, and the eGFR is above the 25 cutoff. A GLP-1-based therapy for kidney protection needs UACR of at least 100 mg/g, so this patient does not yet meet that threshold. Monitor potassium after starting.
Why is BMI alone no longer considered adequate for assessing adiposity?
It misclassifies in both directions. It misses the normal-BMI patient with central adiposity carrying the metabolic risk, and overcalls the muscular patient. The guideline recommends BMI and waist circumference together, with abdominal obesity at 88 cm or more in women and 102 cm or more in men.
Where has metformin moved in this guideline?
From mandatory first step to glycemic add-on. In CKM Stage 2 to 3 with T2DM and elevated CVD risk, the Class 1 recommendation is an SGLT2 inhibitor or GLP-1-based therapy. Metformin is Class 2a, added when the A1c sits 0.5% to 1% above the individualized goal, on top of the cardioprotective agent.
Clinical Scenario
A 52-year-old with BMI 34, waist 108 cm, hypertension on lisinopril, and A1c 7.4%. No known CVD. eGFR 68, UACR 45 mg/g. PREVENT 10-year CVD risk 9%.
Stage: this is CKM Stage 2, metabolic risk factors plus albuminuric CKD, and not Stage 3, since the PREVENT risk is below 20% and there is no subclinical CVD documented. Screening that is now owed annually: lipids, glycemia and blood pressure, plus both eGFR and UACR. A FIB-4 is indicated every 1 to 2 years because he has diabetes plus other cardiometabolic risk factors. Therapy: his PREVENT risk of 9% exceeds the 7.5% threshold, so the plan should include an SGLT2 inhibitor or a GLP-1-based therapy, choosing by comorbidity, and the obesity and albuminuria both argue for it. The lisinopril should be pushed to the maximum tolerated dose rather than left at the starting dose. Target 5% to 10% weight loss, with pharmacotherapy if lifestyle alone falls short. The trap: reflexively starting metformin first and stopping there. On A1c alone that looks reasonable, but it leaves the Class 1 cardioprotective agent unstarted in a patient who qualifies for it on risk.
⚡ Summary
One-Screen Summary
One Syndrome, Five Stages
Obesity, T2DM, CKD and CVD are staged together from 0 to 4 rather than managed as separate diseases. Stage 4 splits into 4a without kidney failure and 4b with it. The 2026 AHA/ACC/ADA/ASN guideline retires the 2013 obesity guideline, and staging applies to youths as well as adults, because the aim is to intervene before progression.
The Stages Run Both Ways
Staging exists to prevent progression and to promote regression through lifestyle change and weight loss. That is what separates it from a risk score, which quotes a probability and implies permanence. It also lets you scale therapy to absolute risk and expected net benefit instead of treating every risk factor identically.
Two PREVENT Numbers Do the Work
A predicted 10-year CVD risk of ≥ 20% is on its own a Stage 3 criterion.A risk of ≥ 7.5% prioritizes starting cardioprotective drug therapy in T2DM. Separately, PREVENT-HF ≥ 5% triggers natriuretic peptide and high-sensitivity troponin testing to find pre-heart-failure while it is still preventable.
Screening Tightens at Stage 2
From Stage 2 upward: lipids, glycemia and blood pressure at least annually, and both eGFR and UACR at least annually.eGFR alone is not enough, because albuminuria comes first and independently predicts events, and because every CKD drug threshold below is written in mg/g of UACR.
Measure the Waist, Not Just the BMI
Assess BMI and waist circumference together (obesity at BMI ≥ 30; abdominal obesity at ≥ 88 cm in women, ≥ 102 cm in men). BMI alone misclassifies in both directions, missing central adiposity at a normal BMI and overcalling the muscular patient. Target 5% to 10% weight loss, the range where metabolic benefit reliably appears.
In Diabetes, Risk Picks the Drug
At 10-year PREVENT-CVD ≥ 7.5%, an SGLT2 inhibitor or GLP-1-based therapy is Class 1, because the benefit is largely independent of glucose lowering. Metformin has moved to a Class 2a add-on when A1c sits 0.5% to 1% above goal, rather than the mandatory first step it used to be.
Four CKD Thresholds
RAS inhibitor at max tolerated dose (UACR ≥ 30, eGFR ≥ 30). SGLT2 inhibitor (T2DM, or UACR ≥ 200, eGFR ≥ 20). Finerenone added when UACR is still ≥ 30 despite both, eGFR ≥ 25. GLP-1 when UACR is still ≥ 100 despite both. The last two are add-ons, not substitutes, and their thresholds differ by more than threefold, so read the UACR before choosing.
The Failure Mode Is Ownership
Interdisciplinary care with a named point person is recommended once T2DM, CKD and CVD overlap. The predictable failure in this population is not a missing guideline recommendation, it is that no single clinician owns the plan. For the same reason, social determinants are assessed as clinical data: a GLP-1 the patient cannot afford is a failed prescription.
Obesity is a chronic disease, not a lifestyle choice. BMI ≥ 30 (or ≥ 27 with comorbidities) qualifies for pharmacotherapy. GLP-1 agonists and tirzepatide have transformed the field -15–25% weight loss is now achievable.
Weekly SC injection. Titrate slowly over 16 weeks (nausea management). Also reduces MACE by 20%SELECT, 2023 -CV benefit independent of diabetes. Contraindicated: personal/family history of medullary thyroid carcinoma, MEN2.
Tirzepatide (Zepbound) MOST EFFECTIVE
Dual GIP + GLP-1 receptor agonist
~20–25% body weightSURMOUNT-1, 2022
Weekly SC injection. Most potent weight loss agent available. Also FDA-approved for T2DM (as Mounjaro). Same GI side effects and contraindications as semaglutide.
Liraglutide 3.0 mg (Saxenda)
GLP-1 RA
~5–8%
Daily SC injection. Less effective than semaglutide but first GLP-1 approved for obesity. Being replaced by weekly options.
Oral. Good for patients with food cravings/binge eating. Avoid in seizure disorders, opioid use, uncontrolled HTN. Bupropion helps with smoking cessation too.
Orlistat (Xenical/Alli)
Lipase inhibitor (blocks fat absorption)
~3–5%
GI side effects (oily stools, flatulence, fecal urgency) limit tolerability. OTC version (Alli 60 mg). Least effective.
Bariatric Surgery
Indications:BMI ≥ 40, or BMI ≥ 35 with obesity-related comorbidity (DM, HTN, OSA, NAFLD). ADA 2026: consider for BMI ≥ 30 with uncontrolled T2DM.
Sleeve gastrectomy: most commonly performed. ~25% excess weight loss. Fewer nutritional deficiencies than RYGB. GERD may worsen.
Most effective long-term treatment for obesity and T2DM -superior to all medications for sustained weight loss and diabetes remission.
📋 On Rounds
Pimp Questions
Why do SGLT2 inhibitors cause weight loss while sulfonylureas cause weight gain?
SGLT2 inhibitors (empagliflozin, dapagliflozin) block sodium-glucose co-transporter 2 in the proximal tubule → glycosuria (urinating out ~70g glucose/day = ~280 kcal/day). This caloric loss drives ~2–3 kg weight loss. Additionally, osmotic diuresis causes initial fluid loss. Sulfonylureas (glipizide, glimepiride) stimulate pancreatic β-cells to release insulin regardless of glucose level → hyperinsulinemia →
A patient asks: 'Will I regain the weight if I stop semaglutide?' What's the evidence?
Unfortunately, yes -most patients regain ~2/3 of lost weight within 1 year of stopping GLP-1 agonists. The STEP 1 extension trial showed that after stopping semaglutide 2.4 mg, participants regained most of the weight they had lost. This is because GLP-1 agonists work by suppressing appetite centrally and slowing gastric emptying -when the drug is removed, appetite returns to baseline.
What are the criteria for bariatric surgery referral?
BMI ≥ 40 (regardless of comorbidities) OR BMI ≥ 35 with ≥ 1 obesity-related comorbidity (T2DM, HTN, OSA, NAFLD/NASH, GERD, OA, dyslipidemia). Some guidelines now support BMI ≥ 30 with uncontrolled T2DM. Types: Roux-en-Y gastric bypass (gold standard, ~30% excess weight loss), sleeve gastrectomy (most common currently, ~25% EWL), adjustable gastric band (declining use).
What are the side effects of GLP-1 agonists that every prescriber should counsel about?
Most common (GI -dose-dependent, typically improve with slow titration): nausea (30-40%), vomiting, diarrhea, constipation, abdominal pain. Counsel: start low and titrate slowly, eat smaller meals, avoid fatty/fried foods. Serious but rare: (1) Pancreatitis: FDA warning, though causal link is debated. Stop if severe abdominal pain + elevated lipase
Clinical Examples
📋 Case 1, GLP-1 RA for Obesity with Comorbidities
Patient: 44M, BMI 38, prediabetes (A1c 6.3), OSA on CPAP, knee OA limiting exercise. Failed 6-month structured diet program (lost 3 kg, regained). Motivated for pharmacotherapy.
Key findings: Pharmacotherapy indicated: BMI ≥ 30 (or ≥ 27 with comorbidities) after failing lifestyle modification. GLP-1 RAs have the most robust evidence for weight loss + cardiometabolic benefit among anti-obesity medications.
Management:
Semaglutide 2.4 mg SQ weekly (Wegovy), titrate from 0.25 mg over 16 weeks to minimize GI side effects STEP 1, 2021
Continue lifestyle modification (medication + lifestyle > either alone)
Counsel on GI side effects: nausea (most common, improves with slow titration), eat smaller meals, avoid fatty foods
Monitor: A1c (may normalize → prevent T2DM), BP, lipids, OSA symptoms (may be able to reduce CPAP pressure)
If weight loss ≥ 5% at 3 months: continue. If < 5%: reassess adherence, consider alternative or combination
Teaching point: Anti-obesity medications are NOT a shortcut, they correct the neurohormonal dysregulation that drives weight regain. Just as we don't shame patients for needing metformin for diabetes, we shouldn't shame them for needing semaglutide for obesity. Weight regain after stopping is expected, not failure.
📋 Case 2, Bariatric Surgery Evaluation
Patient: 52F, BMI 46, T2DM (A1c 9.4 on insulin + metformin), HTN on 3 drugs, OSA, NASH with fibrosis. Failed semaglutide (intolerable GI effects). Interested in surgical options.
Key findings: Bariatric surgery indicated: BMI ≥ 40 (or ≥ 35 with obesity-related comorbidities). This patient has multiple comorbidities likely to improve or resolve with surgery. T2DM remission rates: 60-80% after Roux-en-Y.
Management:
Multidisciplinary bariatric evaluation: surgeon, dietitian, psychologist, medical clearance
Roux-en-Y gastric bypass (RYGB): 25-35% total body weight loss, highest T2DM remission rate, durable results STAMPEDE, 2017
Teaching point: Bariatric surgery is the most effective treatment for severe obesity, it produces durable weight loss AND remission of T2DM, HTN, and OSA in a large proportion of patients. RYGB is superior to sleeve for T2DM remission but has higher long-term complication rates.
📋 Case 3, Tirzepatide for Obesity + T2DM
Patient: 58F, BMI 36, T2DM (A1c 8.1 on metformin), no ASCVD. Insurance covers tirzepatide for diabetes. Wants weight loss and glucose control simultaneously.
Key findings: Tirzepatide (dual GIP/GLP-1 agonist) achieves greater weight loss than semaglutide in head-to-head trials. At highest dose, mean weight loss ~20-25%, approaching surgical levels.
Management:
Tirzepatide 2.5 mg SQ weekly → titrate q4 weeks to max 15 mg (slow titration essential for GI tolerance) SURMOUNT-1, 2022
May be able to reduce or stop insulin as A1c improves
Monitor for pancreatitis (rare but reported), gallstones (rapid weight loss increases risk)
Discuss: weight regain occurs if medication is stopped, likely lifelong therapy needed for weight maintenance
Teaching point: Tirzepatide represents a paradigm shift, 20%+ weight loss was previously only achievable with surgery. The dual GIP/GLP-1 mechanism provides more weight loss than GLP-1 alone. Long-term data on cardiovascular outcomes is pending (SURPASS-CVOT ongoing).
📣 Sample Presentation
One-Liner
"Mr. Rodriguez is a 42-year-old with BMI 38, prediabetes (A1c 6.2), OSA on CPAP, and knee osteoarthritis. He has tried diet and exercise programs without sustained weight loss. Interested in pharmacotherapy."
Key Points to Cover on Rounds
BMI 38 with obesity-related comorbidities (prediabetes, OSA, OA). Prior weight loss attempts: commercial programs, lost 10 lbs but regained. Pharmacotherapy options discussed: (1) semaglutide 2.4 mg SQ weekly (most effective, ~15% weight loss [STEP 1, 2021]), (2) tirzepatide (dual GIP/GLP-1, ~20% weight loss [SURMOUNT-1, 2022]). Starting semaglutide 0.25 mg weekly, uptitrate monthly to 2.4 mg. Counseling: medication is one component alongside lifestyle (goal: 150 min/week moderate exercise, dietary changes). Insurance coverage checked. Bariatric surgery discussed as alternative (BMI ≥35 + comorbidities = eligible). Plan: monthly follow-up for dose titration, weight, and A1c monitoring.
🧪 Workup
Workup -Obesity
1. Measure and stage
BMI plus waist circumference. BMI alone misses central adiposity, which is what carries the cardiometabolic risk. Measure both.
Use lower BMI thresholds in South and East Asian patients, in whom metabolic risk begins at a lower BMI, so the standard cut-points under-call disease.
Stage by complications, not by weight alone. The presence of a weight-related complication, rather than the number itself, is what justifies escalating therapy.
2. Screen for the complications that change management
Dysglycemia: A1c or fasting glucose. Prediabetes strengthens the case for a GLP-1 based agent.
Lipids and blood pressure, with cardiovascular risk assessment.
Liver: ALT and AST, with a fibrosis score such as FIB-4. Metabolic dysfunction-associated steatotic liver disease is common and usually silent.
Obstructive sleep apnea: screen with STOP-BANG. It is underdiagnosed, and treating it improves the symptoms patients often attribute to weight alone.
Mental health and eating pattern, including binge eating, which changes the therapeutic approach.
3. Exclude secondary and iatrogenic causes
TSH for hypothyroidism; consider Cushing syndrome where there are suggestive features, since neither is common but both are treatable.
Review the medication list for weight-promoting drugs: several antipsychotics, some antidepressants, glucocorticoids, insulin and sulfonylureas, and certain antiepileptics. Substituting a weight-neutral alternative is often the highest-yield intervention available.
Before prescribing a GLP-1 receptor agonist, check specifically for: a personal or family history of medullary thyroid carcinoma or MEN2, which is a contraindication; a history of pancreatitis; gastroparesis or significant gastrointestinal disease; and pregnancy or plans to conceive. Ask these before the prescription, not after the first side effect.
💊 Medications
Medications
Anti-obesity medication details (GLP-1 agonists, semaglutide, liraglutide; dual GIP/GLP-1, tirzepatide; phentermine/topiramate; naltrexone/bupropion; orlistat) with evidence-based dosing, weight-loss percentages, and trial citations (STEP 1, SURMOUNT-1, SELECT, SCALE) are in the Management tab.
⚡ Summary
Summary
Treat It as a Chronic Disease
Obesity is a chronic relapsing disease, not a lifestyle choice or a failure of willpower.BMI 30 or above, or 27 or above with a weight-related comorbidity, qualifies for pharmacotherapy alongside lifestyle intervention. Weight regain on stopping treatment is the expected biology, not relapse of bad behavior.
Stage Beyond BMI
BMI misclassifies the muscular and the sarcopenic, and it performs differently across ethnic groups, with lower thresholds appropriate in South Asian populations. Add waist circumference and, above all, the complications: type 2 diabetes, MASLD, obstructive sleep apnea, osteoarthritis, hypertension, dyslipidemia and infertility. The complications, not the number, determine urgency.
Know What the New Agents Achieve
Semaglutide gives roughly 15% weight loss and tirzepatide, a dual GIP/GLP-1 agonist, roughly 20 to 25%, which is a different order of magnitude from older agents. Semaglutide also reduces major cardiovascular events in patients with established cardiovascular disease and obesity without diabetes (SELECT), so this is no longer only a weight intervention.
Titrate Slowly and Manage the GI Effects
Nausea, vomiting, diarrhea and constipation are dose-related and are the main reason patients stop.Escalate on schedule, not faster, and hold at a tolerated dose. Advise smaller meals and less fat. Most GI effects settle over weeks, and warning the patient in advance is what keeps them on treatment.
Screen Before the First Dose
Personal or family history of medullary thyroid carcinoma or MEN2 is a contraindication. Also check for a history of pancreatitis, gastroparesis or significant gastrointestinal disease, and active gallbladder disease. Rapid weight loss itself increases gallstone risk, so the association is partly a consequence of success.
Adjust the Other Diabetes Drugs
Reduce insulin and stop or reduce sulfonylureas when starting a GLP-1 agonist, because the combination causes hypoglycemia. GLP-1 agonists alone rarely cause hypoglycemia, since their insulin effect is glucose-dependent. Also flag the delayed gastric emptying before elective procedures requiring sedation.
Preserve Muscle and Plan for Maintenance
A substantial fraction of the weight lost is lean mass, so resistance exercise and adequate protein intake are part of the prescription rather than optional advice. Weight is regained when the drug stops (STEP 4), so frame treatment as ongoing, and discuss cost and coverage honestly at the outset, since that is what most often ends therapy.
Know When Surgery Is the Better Answer
BMI 40 or above, or 35 or above with comorbidity, and increasingly BMI 30 to 35 with poorly controlled type 2 diabetes.Bariatric surgery produces the largest and most durable weight loss and reduces mortality, with high rates of diabetes remission. It commits the patient to lifelong micronutrient supplementation and monitoring for B12, iron, calcium, vitamin D and thiamine, and to a real perioperative and long-term complication profile.
🔍 Overview
Overview -Obesity Management & GLP-1 Agents
See the tabs above for the complete clinical reference: Workup, Management, Medications, Monitoring, Rounds, Summary, and One Pager.
RoundsRx Infographic Series · #156 · Renal & Metabolic · PDF 151 KB
Text version
Endocrine / Primary Care · One Pager
Obesity
BMI ≥ 30 = obesity. GLP-1 RAs are transformative (~15-20% weight loss). Bariatric surgery for BMI ≥ 40 or ≥ 35 + comorbidity. Lifestyle is foundation but insufficient alone for severe obesity.
🧪 Classification
BMI 25-29.9 = overweight. 30-34.9 = class I obesity. 35-39.9 = class II. ≥ 40 = class III. Screen for comorbidities: OSA, NAFLD, T2DM, HTN, dyslipidemia.
🚨 Pharmacotherapy
Semaglutide 2.4 mg SQ weekly (~15% weight loss [STEP 1, 2021]). Tirzepatide (dual GIP/GLP-1, ~20% [SURMOUNT-1, 2022]). Titrate slowly to minimize GI side effects. Lifestyle (150 min/week exercise + dietary changes) is always the foundation.
Outpatient Diabetes ManagementOutpatient Lipid ManagementPreventive Care & ScreeningSmoking Cessation
Ambulatory
Smoking Cessation
The single most impactful preventive intervention in medicine. Smoking cessation reduces all-cause mortality more than any drug you will ever prescribe. Ask every patient, every visit. Combination NRT + varenicline has the highest quit rate.
🚭 Pharmacotherapy
5 A's Framework
Ask -about tobacco use at every visit
Advise -to quit in a clear, personalized way ("Quitting is the single best thing you can do for your health")
Assess -willingness to make a quit attempt
Assist -offer medication + counseling (combination is most effective)
Arrange -follow-up within 1 week of quit date
Agent
Dose
Quit Rate
Notes
Varenicline (Chantix) MOST EFFECTIVE
0.5 mg daily × 3 days → 0.5 mg BID × 4 days → 1 mg BID × 12 weeks. Can extend to 24 weeks.
~30% at 1 year
Partial nicotine receptor agonist (reduces craving + blocks reward from smoking). FDA removed black box warning for neuropsych eventsEAGLES, 2016 -safe even in psychiatric patients. Start 1 week before quit date. GI side effects (nausea -take with food). Can combine with NRT for even higher efficacy.
Apply to clean, hairless skin, rotate sites. Combine patch (sustained) + lozenge or gum (acute cravings) for best results -combination NRT is as effective as varenicline.
NRT -gum/lozenge
2 mg or 4 mg (if first cigarette within 30 min of waking → 4 mg). Use q1–2h PRN.
~15–20%
Best as add-on to patch for breakthrough cravings. Gum: "park and chew" technique. Lozenge: dissolve in mouth, don't chew.
Bupropion SR (Zyban)
150 mg daily × 3 days → 150 mg BID × 12 weeks. Start 1–2 weeks before quit date.
~20%
Also treats depression. Contraindicated in seizure disorders, eating disorders, MAOI use. Weight-neutral (unlike most cessation -patients often gain 5–10 lbs). Can combine with NRT.
Highest quit rates: Varenicline + NRT patch (~35%), Varenicline alone (~30%), Combination NRT (patch + gum/lozenge, ~28%), Bupropion + NRT (~25%). All superior to counseling alone (~5–10%). Always combine pharmacotherapy with behavioral counseling (quitline: 1-800-QUIT-NOW).
📋 On Rounds
Pimp Questions
A patient says 'I've tried quitting before and it didn't work.' How do you respond?
This is actually encouraging, not discouraging. Most successful quitters have tried 6–8 times before finally quitting permanently. Each attempt teaches the patient about their triggers, cravings, and what strategies work or don't work for them. The response: 'That's actually great -it means you've been working at this. Most people need several attempts. Let's figure out what happened last time and try a different approach.' Then assess
Why is varenicline more effective than NRT alone?
Varenicline (Chantix) is a partial agonist at the α4β2 nicotinic acetylcholine receptor -the same receptor that nicotine binds. It works through a dual mechanism: (1) Agonist effect (~50% activation): provides a low level of dopamine release in the nucleus accumbens → reduces craving and withdrawal symptoms (similar to NRT but via the same receptor)
What is the evidence for combining varenicline with NRT patch?
Combination therapy (varenicline + NRT patch) is the most effective smoking cessation strategy. A meta-analysis and the VARNIC trial showed ~35-40% quit rates at 12 weeks (vs ~25% for varenicline alone, ~20% for NRT alone, ~5-10% for counseling alone).
What does the USPSTF say about e-cigarettes/vaping for smoking cessation?
USPSTF has NOT endorsed e-cigarettes for cessation -evidence is insufficient. While some studies show higher quit rates with e-cigs vs NRT (particularly the UK NIHR trial), concerns remain: (1) Dual use: many smokers vape AND smoke → no net benefit. (2) Long-term safety unknown: EVALI outbreak (2019) raised concerns, though most cases were linked to THC/vitamin E acetate, not nicotine e-cigs
Clinical Examples
📋 Case 1, Varenicline + Behavioral Counseling
Patient: 54M, 35-pack-year smoker, COPD, HTN. Failed NRT patch × 2 prior attempts. Motivated to quit (Prochaska: preparation stage). No history of seizures or psychiatric illness.
Key findings: High nicotine dependence (Fagerström score 7/10), multiple prior failures with NRT alone. Combination pharmacotherapy + counseling has highest quit rates.
Management:
Varenicline 0.5 mg daily × 3 days → 0.5 mg BID × 4 days → 1 mg BID × 12 weeks (most effective single agent, 33% quit rate vs 14% placebo)
Set quit date 1-2 weeks after starting (allows drug to reach steady state)
Behavioral counseling: 1-800-QUIT-NOW (quitline doubles quit rates when combined with meds)
Consider combo: varenicline + nicotine patch (JAMA 2014: combo superior to varenicline alone)
Warn: nausea (most common side effect, take with food). Vivid dreams. Psychiatric monitoring
Teaching point: Varenicline is the most effective single cessation agent. The old FDA black box warning for psychiatric events was REMOVED in 2016 after the EAGLES trial showed no increased risk. Do not withhold from patients with psychiatric history.
📋 Case 2, Inpatient Smoking Cessation After ACS
Patient: 48M admitted for NSTEMI, underwent PCI. 25-pack-year smoker. Currently nicotine-deprived and motivated. Asking about quitting.
Key findings: Hospitalization for ACS is a "teachable moment", quit rates are highest when cessation is initiated during admission. Continued smoking post-ACS doubles the risk of recurrent MI and death.
Management:
Start NRT in hospital: nicotine patch 21 mg/day + nicotine lozenge 2 mg PRN (combo NRT during admission)
Add varenicline before discharge if no contraindication (start during admission → continue outpatient)
Brief motivational interviewing: "How important is quitting to you on a scale of 1-10? What would make it higher?"
Arrange follow-up: smoking cessation clinic or quitline within 1 week of discharge
Document smoking status and cessation plan in discharge summary
Teaching point: Every admission is an opportunity. The 5 A's: Ask (smoking status), Advise (quit), Assess (readiness), Assist (meds + counseling), Arrange (follow-up). NRT is safe in ACS, nicotine from patches causes far less cardiovascular harm than nicotine from cigarettes.
📋 Case 3, Pregnant Smoker
Patient: 28F, 10-pack-year smoker, newly pregnant (8 weeks). Smoking 10 cigarettes/day. Concerned about harm to baby but unable to quit cold turkey.
Key findings: Smoking during pregnancy: risk of preterm birth (2×), low birth weight, placental abruption, SIDS, and childhood asthma. Behavioral counseling is first-line in pregnancy. Pharmacotherapy options are limited.
If counseling alone fails: nicotine patch (lowest effective dose), benefits of quitting likely outweigh NRT risks, but discuss shared decision-making
Varenicline and bupropion are NOT recommended in pregnancy (insufficient safety data)
Motivational framing: "Quitting before 15 weeks eliminates most of the excess risk to your baby"
Postpartum relapse prevention, 70% of women who quit during pregnancy relapse within 6 months postpartum
Teaching point: Behavioral counseling is first-line for pregnant smokers. NRT can be used if counseling fails, the risk of continued smoking far outweighs NRT risk. The critical window is quitting before 15 weeks, which nearly eliminates the excess risk of preterm birth and low birth weight.
📣 Sample Presentation
One-Liner
"Ms. Davis is a 52-year-old with 30-pack-year smoking history, COPD, and HTN. She wants to quit but has tried cold turkey twice and relapsed within 2 weeks both times. Ready to try medication."
Key Points to Cover on Rounds
Pack-year: 30. Prior quit attempts: 2 (cold turkey -no pharmacotherapy). Stage of change: preparation (ready to set quit date). Pharmacotherapy plan: varenicline 0.5 mg daily × 3 days → 0.5 mg BID × 4 days → 1 mg BID (start 1 week before quit date, continue × 12 weeks). Added NRT patch 21 mg/day for combination therapy (varenicline + NRT = highest quit rate ~35%). Quit date set: 2 weeks from today. Behavioral counseling: quitline referral (1-800-QUIT-NOW), trigger avoidance strategies discussed. LDCT lung cancer screening: eligible (50-80 yo, ≥20 pack-years) -ordered. Plan: follow-up call at 1 week post-quit date, office visit at 4 weeks.
🔍 Overview
Overview
See the tabs above for the complete smoking cessation reference: Workup, Management, Medications, Rounds, Summary, and One Pager.
🧪 Workup
Workup
See the Overview and Management tabs for the smoking cessation assessment framework (5 A's, Ask, Advise, Assess, Assist, Arrange; pack-year history; readiness-to-quit stages; triggers; co-morbid psychiatric/substance use).
⚡ Management
Management
See the Management tab for the full stepwise smoking cessation algorithm, behavioral counseling + pharmacotherapy combinations, follow-up timing, and relapse management.
💊 Medications
Medications
Medication details (varenicline, bupropion, NRT combinations, patch + gum/lozenge) with evidence-based dosing and trial citations are in the Management tab.
⚡ Summary
Summary
The Highest-Yield Intervention You Have
Smoking cessation reduces all-cause mortality more than any drug you will prescribe.Ask every patient at every visit: brief advice from a clinician measurably raises quit rates, and a hospital admission is one of the most effective teachable moments there is.
Use the 5 A's
Ask, Advise, Assess, Assist, Arrange.The step that gets skipped is Arrange, and follow-up contact is what converts an intention into a quit. Set a quit date, remove tobacco from the home, and plan for triggers and for the first difficult week.
Combination Therapy Beats Monotherapy
Varenicline plus a nicotine patch gives the highest quit rates, around 35%.Varenicline alone about 30%, combination NRT (patch plus gum or lozenge) about 28%, bupropion plus NRT about 25%.All are far superior to counseling alone, at 5 to 10%.Always pair pharmacotherapy with behavioral support: each roughly doubles the effect of the other.
Combine Long-Acting and Short-Acting NRT
The patch provides a steady baseline; gum, lozenge or inhaler covers breakthrough cravings.Using the patch alone under-treats, because cravings are episodic and a steady-state delivery cannot answer them. Dose the patch by cigarettes per day and start it on the quit date.
Varenicline Is Safer Than Its Reputation
EAGLES found no significant increase in neuropsychiatric events compared with placebo or the other agents, and the FDA boxed warning was removed. Start it 1 week before the quit date and continue for 12 weeks, with nausea and vivid dreams as the usual side effects and dose reduction in renal impairment.
Know When Not to Use Bupropion
Contraindicated with a seizure disorder, an eating disorder, or in a patient at risk of alcohol or benzodiazepine withdrawal, because it lowers the seizure threshold. It is a reasonable choice when depression coexists, and it reduces the post-cessation weight gain that puts some patients off.
Reframe Relapse as Data
Most successful quitters make several attempts.Treat a relapse as information about the trigger rather than as a failure, and re-engage rather than waiting for the patient to raise it again. Ask what worked and for how long, and change the regimen accordingly.
Adjust the Other Medications After They Quit
Tobacco smoke induces CYP1A2, so stopping raises levels of clozapine, olanzapine, theophylline and caffeine, sometimes to toxicity within days. Reduce those doses at cessation rather than waiting for symptoms. Also share the concrete benefits: risk of myocardial infarction falls within a year, and lung cancer risk falls substantially over a decade, which motivates more than a general warning does.
RoundsRx Infographic Series · #185 · General Medicine · PDF 141 KB
Text version
AMBULATORY · One Pager
Smoking Cessation
The single most impactful preventive intervention in medicine: ask every patient every visit, and pair pharmacotherapy with counseling because either one alone leaves most of the benefit on the table.
🧪 The 5 A's (takes 3 minutes)
Ask about tobacco use at every visit, because status changes and a documented ask is what triggers the rest of the pathway.
Advise to quit in a clear, personalized way: "Quitting is the single best thing you can do for your health."
Assess willingness to make a quit attempt, since this decides whether you set a quit date today or do motivational work instead.
Assist with medication plus counseling, because the combination substantially outperforms either alone.
Arrange follow-up within 1 week of the quit date, which is when relapse risk peaks.
A prior failed attempt is a good sign, not a bad one. Most successful quitters try 6-8 times first; each attempt teaches the patient their triggers and what does not work.
⚡ Quit Rates, Highest First
Varenicline + NRT patch: ~35%. The most effective strategy, so this is the default offer unless something contraindicates it.
Varenicline alone: ~30% at 1 year, the most effective single agent.
Combination NRT (patch + gum or lozenge): ~28%, which is roughly as effective as varenicline and matters when varenicline is unavailable or refused.
Bupropion + NRT: ~25%.
Bupropion alone: ~20%; NRT patch alone: ~15-20%.
Counseling alone: ~5-10%. Every pharmacotherapy option beats it, which is the argument for always offering a drug.
🚨 Assist, Step by Step
1
Pick the agent: varenicline plus NRT patch if no contraindication, since it has the highest quit rate. Bupropion is the alternative when depression coexists, and combination NRT when varenicline is not an option.
2
Start the drug BEFORE the quit date: varenicline 1 week ahead, bupropion 1-2 weeks ahead. Both need time to reach steady state so cravings are already blunted on day one.
3
Set an explicit quit date and titrate through it, so the plan has a fixed target rather than an open-ended intention.
4
Add behavioral counseling: quitline 1-800-QUIT-NOW, trigger-avoidance strategies. Counseling roughly doubles quit rates when combined with medication.
5
Arrange follow-up within 1 week of the quit date (relapse risk is highest early), then an office visit at about 4 weeks to check adherence, side effects, and whether to extend therapy.
6
Treat the full 12 weeks, extending varenicline to 24 weeks in patients who need it, because stopping at the first sign of success is a common relapse trigger.
💊 Key Drugs
Varenicline (Chantix)0.5 mg daily × 3 days → 0.5 mg BID × 4 days → 1 mg BID × 12 weeks, extendable to 24 weeks. Start 1 week before the quit date. Partial nicotine receptor agonist: it reduces craving and blocks the reward from smoking. Nausea is the main side effect, so take with food.
NRT patch21 mg/day × 6 wks → 14 mg × 2 wks → 7 mg × 2 wks if > 10 cig/day; start at 14 mg if < 10/day. Apply to clean hairless skin and rotate sites. Provides the sustained baseline level, not breakthrough coverage.
NRT gum / lozenge2 mg, or 4 mg if the first cigarette is within 30 min of waking (a marker of higher dependence). Use q1-2h PRN. Best as the add-on to the patch for breakthrough cravings. Gum uses "park and chew"; lozenge dissolves and is not chewed.
Bupropion SR (Zyban)150 mg daily × 3 days → 150 mg BID × 12 weeks, starting 1-2 weeks before the quit date. Also treats depression and is weight-neutral, which matters because quitters often gain 5-10 lbs. Can be combined with NRT.
📊 Screening & Follow-Up
Annual LDCT lung cancer screening: age 50-80, ≥ 20 pack-years, and currently smoking or quit within 15 years (USPSTF 2021). It reduces lung cancer mortality 20% (NLST), so eligibility should be checked at the same visit you address cessation.
Follow-up call at 1 week post-quit date, office visit at 4 weeks: early relapse is the dominant failure mode and is often fixable by adding a short-acting NRT or adjusting the dose.
Document pack-years, prior quit attempts, and stage of change, because the number of prior attempts and what failed last time drives the next regimen choice.
Counsel on weight gain (typically 5-10 lbs) up front, so it does not become an unspoken reason to relapse. Bupropion is the weight-neutral option.
Warn about varenicline side effects: nausea (take with food) and vivid dreams, both of which patients stop the drug over if they are not forewarned.
⚠️ Pitfalls
Withholding varenicline from patients with psychiatric illness. The FDA removed the neuropsychiatric black box warning in 2016 after EAGLES, 2016 showed no increased risk. These are exactly the patients who need the most effective drug.
Bupropion in a patient with a seizure disorder, eating disorder, or on an MAOI. All are contraindications.
Using the patch alone and calling it maximal therapy. The patch covers baseline; add a gum or lozenge for acute cravings, which lifts the quit rate from ~15-20% to ~25-30%.
Starting the drug on the quit date. Varenicline needs a week and bupropion 1-2 weeks to reach steady state first.
Treating a prior failed attempt as evidence the patient cannot quit. Reframe it: most quitters need several attempts, and the useful question is what happened last time.
Recommending e-cigarettes as cessation therapy. USPSTF has NOT endorsed them, evidence is insufficient, dual use means many patients get no net benefit, and long-term safety is unknown.
🏥 Special Populations
Pregnancy: behavioral counseling is first-line (pregnancy-specific programs achieve 5-10% quit rates, which doubles with intensive support). Varenicline and bupropion are NOT recommended given insufficient safety data. If counseling fails, nicotine patch at the lowest effective dose with shared decision-making, since continued smoking carries clearly greater risk.
Pregnancy, the framing that motivates: quitting before 15 weeks eliminates most of the excess risk to the baby (preterm birth 2×, low birth weight, placental abruption, SIDS, childhood asthma). Plan postpartum relapse prevention, because 70% of women who quit in pregnancy relapse within 6 months.
Inpatient after ACS: admission is a teachable moment with the highest quit rates. Start combination NRT in hospital (patch 21 mg/day plus lozenge 2 mg PRN) and add varenicline before discharge. NRT is safe in ACS: nicotine from a patch causes far less cardiovascular harm than nicotine from cigarettes, and continued smoking post-ACS doubles the risk of recurrent MI and death.
Any hospitalization: document smoking status and the cessation plan in the discharge summary, and arrange quitline or cessation clinic follow-up within 1 week of discharge.
🎓 Key Evidence
EAGLES, 2016: no excess neuropsychiatric events with varenicline or bupropion, including in psychiatric patients. This is why the FDA black box came off and why you should not withhold the drug.
NLST: annual LDCT reduced lung cancer mortality 20%, the basis for the USPSTF 2021 screening criteria (age 50-80, ≥ 20 pack-years, current or quit within 15 years).
Combination beats monotherapy: varenicline plus NRT patch reaches ~35%, versus ~30% varenicline alone and ~5-10% for counseling alone, which is the practical case for always layering drug plus counseling.
The bread and butter of outpatient medicine. Know the USPSTF A/B recommendations cold -cancer screening, cardiovascular risk assessment, and immunizations. This is what keeps patients out of the hospital.
🔬 Cancer Screening (USPSTF)
Cancer
Test
Age / Frequency
Key Notes
Breast
Mammography
40–74, every 2 years (USPSTF 2024 update -lowered from 50 to 40)
Shared decision 40–49 in prior guidelines. Now routine. High-risk (BRCA, family hx) → may add MRI.
Cervical
Pap ± HPV
21–65. Pap q3 years (21–29). Pap + HPV co-test q5 years or HPV alone q5 years (30–65).
Stop at 65 if adequate prior screening. No screening if hysterectomy (no cervix) for non-cancer indication.
Colorectal
Colonoscopy, FIT, Cologuard
45–75. Colonoscopy q10 years, FIT annually, Cologuard q3 years.
USPSTF 2021 lowered from 50 to 45. 76–85 = selective. Family hx → start 10 years before youngest affected relative or age 40.
Lung
Low-dose CT (LDCT)
50–80, ≥ 20 pack-years, current or quit within 15 years. Annual.
55–69: shared decision-making. USPSTF does NOT recommend routine screening.
PSA has high false-positive rate → unnecessary biopsies. Discuss benefits/harms. Not recommended > 70.
Other Key Screenings
Condition
Screening
Population
AAA
One-time abdominal US
Men 65–75 who ever smoked
Hepatitis C
Anti-HCV antibody
All adults 18–79 (one-time). USPSTF 2020.
HIV
HIV Ag/Ab combo
All adults 15–65 (one-time or more if high-risk). USPSTF 2019.
Diabetes
Fasting glucose, A1c, or OGTT
35–70 with overweight/obesity. Screen q3 years.
Osteoporosis
DEXA scan
Women ≥ 65. Younger postmenopausal if FRAX 10-year hip fracture risk ≥ 3%.
Depression
PHQ-2 → PHQ-9
All adults. USPSTF 2016.
❤️ Cardiovascular Risk
Statin Therapy (ACC/AHA 2018)
Group
Recommendation
1. Clinical ASCVD (prior MI, stroke, PAD)
High-intensity statin (atorvastatin 40–80 mg or rosuvastatin 20–40 mg) 4S, 1994. Target LDL < 70. Add ezetimibe if not at goal → add PCSK9 inhibitor if still not at goal.
First-line agents: ACEi/ARB (preferred if DM, CKD, proteinuria, HF), thiazide (chlorthalidone preferred), CCB (amlodipine). Start 2 of 3 for stage 2.
Resistant HTN (≥ 3 drugs at max doses): screen for OSA, hyperaldosteronism, renal artery stenosis. Add spironolactone PATHWAY-2, 2015.
🏥 Rounds
Pimp Questions
USPSTF recently lowered the mammography screening start age. What changed and why?
In 2024, USPSTF lowered the recommended start age for mammography screening from 50 to 40, with biennial screening through age 74. The change was driven by rising breast cancer incidence in women under 50 -particularly Black women, who have higher rates of aggressive subtypes (triple-negative) and present at younger ages. The prior recommendation (50–74, with "individual decision" for 40–49) led to disparities in screening uptake.
A 52-year-old male with no history of heart disease has an LDL of 130 and a 10-year ASCVD risk of 8%. Does he need a statin?
This falls into ACC/AHA Group 4: non-DM, LDL 70–189, 10-year ASCVD risk 7.5–20% → moderate to high-intensity statin is recommended. At 8% risk, a statin is indicated. However, for borderline cases (5–7.5%), you'd use risk enhancers to guide the decision: family history of premature ASCVD, persistently elevated CRP (> 2), elevated Lp(a), South Asian ancestry, metabolic syndrome, or coronary artery calcium (CAC) score > 0.
When do you start lung cancer screening with LDCT and who qualifies?
USPSTF 2021 recommendation: Annual LDCT for adults aged 50-80 with ≥ 20 pack-year smoking history who currently smoke OR quit within the last 15 years. This was expanded from the previous criteria (55-80, ≥ 30 pack-years) to capture more at-risk individuals. Stop screening when: the person has not smoked for 15 years, develops a health problem that limits life expectancy or willingness to have curative surgery, or turns 81.
What cancer screenings are recommended by USPSTF and at what ages?
Breast: Mammography every 2 years, ages 40-74 (updated 2024 -lowered from 50). Cervical: Pap every 3 years ages 21-29, Pap + HPV co-test every 5 years ages 30-65. Colorectal: Start at 45 (updated from 50). Options: colonoscopy q10y, FIT annually, Cologuard q3y, CT colonography q5y, flex sig q5y. Lung: Annual LDCT ages 50-80 with ≥ 20 pack-year history + currently smoke or quit within 15 years. Prostate: Shared decision-making ages 55-69 (PSA screening -NOT universal recommendation). Not recommende
🔍 Overview
Overview
Preventive medicine is the highest-yield intervention. USPSTF Grade A/B recommendations guide screening. Key domains: cancer screening, CV risk, immunizations, behavioral counseling.
🧪 Workup
Workup
Cancer screening: mammogram, Pap/HPV, colonoscopy, LDCT
Very limited role in primary prevention.ASCEND, 2018: bleeding offsets benefit in diabetes. USPSTF 2022: do NOT initiate for age ≥ 60. Consider only age 40–59 with ≥10% ASCVD risk via shared decision-making.
📋 On Rounds
📣 Sample Presentation
One-Liner
"Mrs. Thompson is a 52-year-old healthy woman presenting for her annual wellness visit. She is up to date on Pap smear (last year, normal) and mammogram (last year, normal). No colonoscopy yet. BMI 26, BP 128/82."
Key Points to Cover on Rounds
Cancer screening: colonoscopy due (age 52, average risk -schedule). Mammogram current (biennial, next in 1 year). Pap current (every 3 years with HPV co-test). Lung CT: not indicated (non-smoker). CV risk: 10-year ASCVD risk 4.2% (low) -no statin currently indicated. BP 128/82 (elevated, not yet HTN -lifestyle counseling). Fasting glucose 94, A1c 5.4 (normal, rescreen in 3 years). Immunizations: flu (today), COVID booster (due), Tdap (up to date), shingrix (not yet eligible -age 50). Depression screening: PHQ-2 negative. Osteoporosis: not yet (screen at 65). Plan: colonoscopy referral, lifestyle counseling (diet, exercise, weight), return in 1 year.
⚡ Summary
Summary
Cancer Screening: Know the Ages
Breast: mammography every 2 years from 40 to 74 (lowered from 50 in 2024). Cervical: Pap every 3 years from 21 to 29, then Pap plus HPV co-test every 5 years from 30 to 65.Colorectal: start at 45 (lowered from 50), by colonoscopy every 10 years, annual FIT, stool DNA every 3 years, or CT colonography every 5. Lung: annual low-dose CT from 50 to 80 with a 20 pack-year history in current smokers or those who quit within 15 years.
Prostate Screening Is a Conversation, Not a Protocol
Shared decision-making from 55 to 69; it is not a universal recommendation. The tradeoff is a modest mortality benefit against overdiagnosis and the morbidity of treating cancers that would never have caused harm. Document the discussion rather than reflexively ordering or omitting the PSA.
Statins by Risk, Not by LDL Alone
Clinical ASCVD or LDL 190 or above: high-intensity statin regardless of calculated risk.Diabetes aged 40 to 75: at least moderate-intensity.Otherwise use the risk estimator, treating at 7.5% or above and considering it at 5 to 7.5% with risk enhancers. Coronary artery calcium scoring resolves the intermediate-risk patient: a score of zero permits deferral, and a score above 100 argues for treatment.
Use the Current Blood Pressure Thresholds
Normal below 120/80, elevated 120 to 129 systolic, stage 1 hypertension 130 to 139 or 80 to 89, stage 2 at 140/90 or above.Confirm with out-of-office readings before labeling anyone hypertensive, because white coat hypertension is common and a diagnosis made on a single clinic reading commits the patient to lifelong therapy.
Screen for the Non-Cancer Conditions Too
Diabetes or prediabetes from 35 to 70 in overweight adults.One-time abdominal aortic aneurysm ultrasound in men 65 to 75 who have ever smoked.Osteoporosis with DEXA in women 65 and over.Hepatitis C once in all adults 18 to 79, hepatitis B and HIV at least once, with more frequent HIV testing by risk.Depression, intimate partner violence and unhealthy alcohol use in all adults.
Vaccinate on Schedule
Influenza annually, COVID-19 per current guidance, Tdap once then Td every 10 years, shingles (Shingrix, two doses) from 50, pneumococcal from 50, RSV in older adults, and HPV through 26 with shared decision-making to 45.Hospital admission is an opportunity, since inpatient vaccination reaches people who do not attend primary care.
Screening Has Harms as Well as Benefits
False positives, overdiagnosis, procedural complications and the anxiety of incidental findings are real costs, which is why the recommendations specify ages and intervals rather than 'more is better'. Stop screening when life expectancy is under about 10 years, since the benefit of finding an early cancer accrues years later while the harms are immediate.
Behavioral Counseling Outperforms Most Tests
Smoking cessation is the single highest-yield intervention in medicine. Add diet and physical activity counseling, alcohol reduction, and weight management. These change more outcomes than any screening test on the list, and they are what the screening visit exists to deliver.
Breast: mammogram q2y 40-74. Cervical: Pap q3y (21-29) or Pap/HPV q5y (30-65). Colon: start age 45 (colonoscopy q10y, FIT annually, Cologuard q3y). Lung: LDCT 50-80 if ≥ 20 pack-year smoker.
🚨 Cardiovascular Prevention
10-year ASCVD risk calculator. Statin: moderate if 7.5-20%, high-intensity if ≥ 20% or known ASCVD. ASA: limited role (ages 40-59, ≥ 10% risk, shared decision). BP target < 130/80 [SPRINT, 2015].
💊 Other Screening
Depression: PHQ-2 annually. Diabetes: A1c q3y if ≥ 35 + overweight. Osteoporosis: DEXA at 65F/70M. Hepatitis C: one-time for all 18-79. HIV: at least once for all 15-65.
💊 Key Drugs
Flu vaccineAnnual
Shingrix≥ 50 (2 doses)
PCV20≥ 65
ColonoscopyEvery 10 years starting at 45
⚠️ Pitfalls
Not doing colonoscopy at 45 (USPSTF lowered from 50)
Missing LDCT eligibility in former smokers
PSA screening without shared decision-making
Forgetting Hepatitis C screening (one-time, all adults)
+ vanc or linezolid if MRSA (linezolid preferred -better lung penetration). + pip-tazo/cefepime if Pseudomonas risk.
7 days
HAP / VAP
Pip-tazo 4.5g q6h or cefepime 2g q8h
+ vancomycin or linezolid for MRSA (linezolid if severe -better lung penetration). Pip-tazo if anaerobic concern (abscess/empyema). Cefepime preferred with vanc (↓ AKI ACORN, 2023). Need cefepime + anaerobes → add metronidazole.
Pip-tazo 4.5g q6h (single agent). Meropenem if ESBL.
4 days (post source control) STOP-IT, 2015
SBP* *= Spontaneous Bacterial Peritonitis
Ceftriaxone (Rocephin) 2g IV daily
Pip-tazo or meropenem if nosocomial/FQ* failure *FQ = Fluoroquinolone (ciprofloxacin, levofloxacin, moxifloxacin)
5 days
🧠 CNS Infections
1 regimen
›
Setting
First-Line
Alternatives
Duration
Bacterial meningitis (adult)
Vanc + ceftriaxone 2g q12h
+ ampicillin 2g q4h if age >50 or immunocompromised (Listeria). Dex before/with 1st abx doseEuropean Dexamethasone Meningitis Trial, 2002.
10–14 days (S. pneumo); 7 days (N. meningitidis)
Antibiotics within 30–60 min. Do NOT delay for LP or CT. Get blood cultures → start abx → then LP.
❤️ Endocarditis
1 regimen
›
Setting
Empiric
Culture-Directed
Duration
Native valve (empiric)
Vanc + ceftriaxone
MSSA → nafcillin/cefazolin. MRSA → vanc or daptomycin. Enterococcus → ampicillin + gentamicin or ampicillin + ceftriaxone.
4–6 weeks
3 sets of blood cultures from 3 sites before antibiotics. Daptomycin is an alternative to vanc for right-sided MRSA endocarditis -but NOT for left-sided (poor penetration through vegetations).
🚨 Sepsis & Febrile Neutropenia
2 regimens
›
Setting
First-Line
Alternatives / Add-On
Duration
Sepsis (unknown source)
Vanc + cefepime or vanc + pip-tazo
Meropenem if ESBL risk or critically ill. Add antifungal if immunocompromised + no improvement day 4–7.
Source-dependent
Neutropenic fever (ANC < 500 + T ≥ 38.3)
Cefepime (Maxipime) 2g IV q8h
+ vanc if hemodynamic instability, line infection, MRSA. + antifungal day 4–7 if persistent fever.
Until ANC recovery + afebrile ≥48h
Antibiotics within 1 hour in sepsis and neutropenic fever. Every hour of delay increases mortality. Empiric broad → narrow based on cultures at 48–72h.
🦠 C. difficile
2 regimens
›
Severity
First-Line
Alternatives
Duration
Non-severe
Fidaxomicin 200 mg BIDPREFERRED
Vancomycin PO 125 mg QID
10 days
Fulminant (ileus, megacolon, shock)
Vanc PO 500 QID + metronidazole IV 500 q8h
± vanc enemas if ileus. Surgical consult for colectomy.
Until resolved
Soap and water for hand hygiene (alcohol sanitizer does NOT kill C. diff spores). Fidaxomicin has lower recurrence rate than vanc IDSA/SHEA, 2021.
🦠 Spectrum of Activity
Gram-Positive Coverage
Drug
MSSA
MRSA
Strep
Enterococcus
Notes
Cefazolin (Ancef) / Cephalexin (Keflex)
✓
✗
✓
✗
Best anti-staphylococcal cephalosporin. First-line MSSA.
Nafcillin / Oxacillin
✓✓
✗
✓
✗
Gold standard MSSA bacteremia / endocarditis.
Vancomycin (Vancocin)
✓
✓
✓
✓ (not VRE)
Workhorse MRSA drug. Nephrotoxic. Target AUC/MIC 400–600 (trough-based monitoring is outdated per 2020 ASHP/IDSA).
Linezolid (Zyvox)
✓
✓
✓
✓ (incl VRE)
Covers VRE. PO = IV bioavailability. Serotonin syndrome risk. Thrombocytopenia >2 weeks.
Daptomycin (Cubicin)
✓
✓
✓
✓ (incl VRE)
Inactivated by surfactant -do NOT use for pneumonia. Check CK weekly (rhabdo).
TMP-SMX (Bactrim)
✓
✓ (CA-MRSA)
Variable
✗
Good oral MRSA option for skin/soft tissue. Not reliable for strep.
Gram-Negative Coverage
Drug
Enterobacteriaceae
Pseudomonas
ESBL
Anaerobes
Notes
Ceftriaxone (Rocephin)
✓✓
✗
✗
✗
Workhorse for community GNR. No Pseudomonas. No anaerobes.
Cefepime (Maxipime)
✓✓
✓
✗
✗
Anti-pseudomonal cephalosporin. Neurotoxic in renal failure (seizures).
Pip-tazo (Zosyn)
✓✓
✓
Variable
✓
Broadest non-carbapenem. Covers Pseudomonas + anaerobes. Workhorse for abdominal/polymicrobial.
Meropenem (Merrem)
✓✓
✓
✓
✓
Broadest spectrum. Reserve for ESBL, MDR, failing empiric therapy. Does NOT cover MRSA.
Aztreonam
✓
✓
✗
✗
Safe in penicillin allergy (monobactam, no cross-reactivity). GNR only -no gram-positive, no anaerobes.
Fluoroquinolones
✓
✓ (cipro)
✗
✗ (moxi has some)
Rising resistance. FDA black box warnings. Save for specific indications (pyelo, prostatitis, Legionella).
Metronidazole (Flagyl)
✗
✗
✗
✓✓
Anaerobe specialist. Also covers C. diff (fulminant, IV), Giardia, amebiasis. Disulfiram reaction with alcohol.
Daptomycin is inactivated by pulmonary surfactant -NEVER use for pneumonia. This is a classic boards and real-life mistake. Use vancomycin or linezolid for MRSA pneumonia.
💊 Renal Dose Adjustments
This table covers antibiotics. For non-antibiotic renal dosing (anticoagulants, diabetes drugs, analgesics, cardiac meds) with renal-friendly alternatives, see the full Drug Dosing in Renal Impairment reference.
Drug
Normal Dose
CrCl 10–30
HD
Key Notes
Vancomycin (Vancocin)
15–20 mg/kg q8–12h
15–20 mg/kg q24–48h (by levels)
Re-dose by levels post-HD
Target AUC/MIC 400–600 (AUC-guided, not trough-only). Nephrotoxic in its own right; the added risk from pairing with pip-tazo was not confirmed by RCT ACORN, 2023.
Pip-tazo (Zosyn)
4.5g IV q6h
2.25g IV q6h
2.25g q6h + dose after HD
Extended infusion (4h) improves outcomes in critically ill.
Cefepime (Maxipime)
2g IV q8h
1g IV q12–24h
1g IV q24h + dose after HD
Neurotoxic in renal failure (encephalopathy, myoclonus, seizures). Monitor closely.
Ineffective (can't concentrate in urine) + pulmonary toxicity risk.
Metronidazole (Flagyl)
500 mg q8h
No adjustment needed
Dose after HD
Hepatically metabolized. No renal adjustment.
Linezolid (Zyvox)
600 mg q12h
No adjustment needed
No adjustment
Not renally cleared. 100% PO bioavailability = IV.
Daptomycin (Cubicin)
6–10 mg/kg IV daily
6–10 mg/kg IV q48h
Dose after HD
Check CK weekly. Not for pneumonia.
🧠 Stewardship Pearls
Always get cultures before antibiotics -but never delay antibiotics for cultures in sepsis or meningitis
De-escalate within 48–72h based on culture/sensitivity. Broad empiric → narrow targeted is the rule.
Shorter is better: CAP 5 days, UTI 3–5 days, intra-abdominal 4 days post-source-control, HAP/VAP 7 days. Longer courses don't improve outcomes and increase resistance + C. diff.
IV to PO switch: switch to oral when afebrile ×48h, tolerating PO, improving clinically. Most antibiotics have excellent oral bioavailability (FQ, linezolid, metronidazole, TMP-SMX, fluconazole).
Vanc + pip-tazo was NOT shown to increase AKI in the only randomized trial, despite a long-standing observational signal ACORN, 2023. Prefer vanc + cefepime when both cover the suspected pathogens.
"Bug-drug mismatch" -common errors: ceftriaxone doesn't cover Pseudomonas; cefazolin doesn't cover MRSA; daptomycin doesn't work in the lung; nitrofurantoin doesn't work above the bladder.
Allergies: ~90% of "penicillin allergies" are not true IgE-mediated. Cephalosporin cross-reactivity is < 2%. Get allergy history details (rash vs anaphylaxis). Consider allergy testing.
Linezolid vs Vancomycin -When to Choose Which
Both cover MRSA. But they are NOT interchangeable. Choosing wrong = treatment failure, unnecessary toxicity, or worse outcomes. Know when each one wins.
Protein synthesis inhibitor -binds 23S rRNA of the 50S ribosome, blocking formation of the 70S initiation complex → prevents translation. Bacteriostatic. Also a weak reversible MAOi (inhibits monoamine oxidase → serotonin syndrome risk).
Route
IV only for systemic infections (PO only for C. diff -not absorbed)
MRSA pneumonia -far superior lung penetration ZEPHyR, 2012
VRE infections -vanc is useless against VRE
CKD / AKI -no renal adjustment, won't worsen kidneys
No IV access -100% PO bioavailability
Outpatient MRSA Tx -go home on PO instead of IV vanc
Vancomycin failure or allergy
Never use daptomycin for pneumonia. Pulmonary surfactant inactivates it. For MRSA pneumonia your choices are vancomycin or linezolid -and linezolid is likely better due to lung penetration.
Linezolid + serotonergic drugs = serotonin syndrome. Always check the med list for SSRIs, SNRIs, MAOIs, tramadol, meperidine before starting linezolid. If the patient is on an SSRI and needs MRSA coverage → use vancomycin.
⚠️ Linezolid Toxicity Timeline: • > 14 days: thrombocytopenia (check CBC twice weekly), myelosuppression, lactic acidosis (check weekly lactate) • > 28 days: peripheral neuropathy (numbness/tingling -may be irreversible), optic neuritis (blurred vision, color vision loss -check visual acuity weekly) • Any duration: serotonin syndrome if on SSRIs/SNRIs/MAOIs/tramadol (linezolid is a weak MAOi) If you need > 2 weeks of MRSA therapy (endocarditis, osteo), vancomycin is safer for long courses.
Toxin suppression -linezolid & clindamycin. Both are protein synthesis inhibitors (50S ribosome) → they suppress bacterial toxin production even before the bacteria die. This is why clindamycin is always added in necrotizing fasciitis (suppresses Group A strep exotoxins), toxic shock syndrome (suppresses TSST-1 and strep pyrogenic exotoxins), and PVL-producing MRSA (Panton-Valentine leukocidin). Linezolid has the same mechanism and can substitute when clindamycin resistance is a concern. Vancomycin kills the bacteria but does NOT suppress toxin production -in toxin-mediated disease, bactericidal alone is not enough.
⏱ Duration by Infection
Respiratory
Infection
Duration
Key Notes / Evidence
CAP (uncomplicated)* *= No ICU admission, no empyema/abscess, no bacteremia, immunocompetent, clinically improving
Complicated UTI* *= UTI extending beyond the bladder (pyelonephritis, urosepsis) OR occurring in a host with impaired urinary tract clearance (male, pregnant, anatomic abnormality, obstruction, catheter, immunocompromised, renal transplant)
7–14 days
Depends on source control. Broader coverage needed (FQ or beta-lactam)
Pyelonephritis (uncomplicated)
5–7 days
FQ 5d, TMP-SMX 7d, beta-lactam 10–14d
Catheter-associated UTI
7 days
Remove or replace catheter. 10–14d if slow response
Prostatitis (acute)
2–4 weeks
FQ or TMP-SMX preferred (prostate penetration)
Bloodstream
Infection
Duration
Key Notes / Evidence
Uncomplicated gram-negative bacteremia = Source identified & controlled, no endovascular infection, no prosthetic material, immunocompetent, defervesced within 72h, cultures cleared
7 days
From first negative blood culture. ALL criteria must be met
RoundsRx Infographic Series · #29 · Sepsis & Infection · PDF 174 KB
Quick Reference
Vasopressor Guide
First-line agents, receptor profiles, dosing, and when to escalate. Know your pressors cold -you'll be titrating them at 3 AM.
Vasopressor Table
Agent
Dose
Receptor
Role
Avoid / Caution
Norepinephrine (Levophed) 1ST LINE
0.01–3 mcg/kg/min
α₁>>β₁
First-line in septic shock: strong recommendation over dopamine, epinephrine and selepressin (SSC 2026). Only the head-to-head against vasopressin or angiotensin II is a conditional "suggest", so do not read that as a general downgrade of NE. ↑ SVR + mild inotropy. SSC, 2026
-
Vasopressin (Vasostrict) ADD-ON
0.03 units/min (fixed, no titration)
V1/V2
Add-on to NE (NE-sparing). May reduce AKI. Add when NE ≥ 0.25–0.5 mcg/kg/min. VASST, 2008
Coronary vasospasm, mesenteric ischemia at higher doses
Epinephrine (Adrenalin) 2ND LINE
0.01–0.5 mcg/kg/min
α₁, β₁, β₂
Refractory shock. Strong inotropy + vasoconstriction. Also cardiac arrest.
Falsely elevates lactate (β₂-mediated aerobic glycolysis) -can't use lactate to guide resuscitation
Phenylephrine (Neo-Synephrine) 3RD LINE
0.5–6 mcg/kg/min
α₁ pure
Use if tachyarrhythmia limits NE use. Pure vasoconstriction.
Low CO states (no inotropy -worsens cardiac output)
Dobutamine (Dobutrex) INOTROPE
2–20 mcg/kg/min
β₁>β₂
Low CO despite adequate MAP (cardiogenic component). Not a vasopressor -an inotrope.
Never use alone if MAP < 65 (drops SVR via β₂). Always pair with NE.
AVOID in sepsis. More arrhythmias, higher mortality vs NE. SOAP II, 2010
Avoid. Only remaining role: symptomatic bradycardia if no pacing available.
Adjuncts
Drug
Indication
Dose
Evidence
Hydrocortisone (Solu-Cortef)
Refractory septic shock with ongoing vasopressor requirement
200 mg/day IV (50 mg q6h or continuous infusion)
ADRENAL, 2018: faster shock reversal, no mortality benefit. APROCCHSS, 2018: 90-day mortality benefit in the overall randomized population (43.0% vs 49.1%), not a subgroup. Its patients were sicker than ADRENAL's (all in shock ≥ 6h on high-dose pressors, and it added fludrocortisone), which is the leading explanation for why the two trials diverged.
1–2 mg/kg IV bolus, may repeat or infuse 0.5 mg/kg/hr
Case series. Inhibits soluble guanylate cyclase (and, less importantly, NO synthase), blocking the NO → cGMP pathway that keeps vascular smooth muscle relaxed in vasoplegia → restores SVR. Rescue agent.
Prevents Wernicke's. May help refractory lactic acidosis.
Escalation Ladder
Stepwise approach to vasopressor escalation in septic shock:
Step 1
Norepinephrine (Levophed) -first-line. Start at 0.05 mcg/kg/min, titrate to MAP ≥ 65.
Step 2
Add vasopressin (Vasostrict) 0.03 u/min when NE ≥ 0.25–0.5 mcg/kg/min. Fixed dose, NE-sparing.
Step 3
Start hydrocortisone (Solu-Cortef) 200 mg/day if still on escalating vasopressors with ongoing requirement. SSC, 2026
Step 4
Add epinephrine (Adrenalin) if refractory. Provides additional inotropy. Watch for lactate confounding.
Step 5
Consider angiotensin II (Giapreza)ATHOS-3, 2017 or methylene blue (ProvayBlue) for catecholamine-refractory vasoplegia. Reassess: is source controlled? Missed adrenal crisis? Cardiac tamponade?
Key Pearls
Never run dopamine in sepsis.SOAP II, 2010: no overall mortality difference (48.5% vs 52.5%, p = 0.10), but double the arrhythmia rate (24.1% vs 12.4%) and higher mortality in the cardiogenic shock subgroup. It is the arrhythmia burden, not a survival signal, that makes NE the better first choice. There is no "renal-dose dopamine."
Epinephrine falsely elevates lactate via β₂-mediated aerobic glycolysis. If you're on epi, you cannot use lactate clearance to guide resuscitation.
Vasopressin is fixed-dose 0.03 u/min. Do not titrate. It's an add-on, not a standalone. Wean NE first, then vaso last.
Dobutamine ≠ vasopressor. It's an inotrope. If MAP is low, you need NE first. Add dobutamine only if MAP is adequate but CO is low (cold extremities, poor ScvO₂ despite adequate MAP).
Key Trials
Trial
Year
Finding
SOAP II
2010
NE vs dopamine in shock (n = 1,679): no difference in 28-day mortality (48.5% NE vs 52.5% dopamine, p = 0.10). Dopamine caused twice the arrhythmias (24.1% vs 12.4%, p < 0.001) and had higher mortality in the cardiogenic shock subgroup only. The arrhythmia signal, not a mortality signal, is why NE is first-line.
VASST
2008
Vasopressin + NE vs NE alone: no overall mortality difference, but possible benefit in less severe shock
VANISH
2016
Vasopressin vs NE as first-line: no difference. Vasopressin may reduce need for RRT.
ADRENAL
2018
Hydrocortisone in septic shock: faster shock reversal, no 90-day mortality benefit
APROCCHSS
2018
Hydrocortisone + fludrocortisone: 90-day mortality benefit in severe septic shock
ATHOS-3
2017
Angiotensin II in vasodilatory shock: improved MAP response vs placebo
Give with meals. Used for bolus dosing and correction scales.
Short-Acting
Regular (Humulin R, Novolin R)
30–60 min
2–4 h
6–8 h
Used in IV drips (DKA). Only insulin safe for IV use.
Intermediate
NPH (Humulin N, Novolin N)
1–2 h
4–12 h
12–18 h
Cloudy vial. Useful for steroid-induced hyperglycemia. Must be resuspended.
Long-Acting
Glargine (Lantus, Basaglar), Detemir (Levemir)
1–2 h
Peakless
20–24 h
Basal insulin of choice. Give once daily (glargine) or BID (detemir). Do NOT mix.
Ultra-Long
Degludec (Tresiba)
1 h
Peakless
42 h
Flexible dosing window. Lowest hypoglycemia risk among basals.
Concentrated
U-500 Regular
30 min
4–8 h
12–24 h
5x concentration of U-100. For severe insulin resistance (>200 units/day). High error risk -requires dedicated syringe.
Inpatient Basal-Bolus Protocol
Goal: Mimic physiologic insulin secretion. Basal covers fasting needs. Bolus covers meals. Correction fixes hyperglycemia. Target BG 140–180 mg/dL for most ICU and non-ICU patients.
1
Calculate Total Daily Dose (TDD): 0.3–0.5 units/kg/day. Start 0.3 units/kg for elderly, CKD (GFR < 30), hepatic impairment, or malnourished. Start 0.5 units/kg for insulin-resistant, obese, or steroid-treated patients.
2
Split TDD: 50% as basal (glargine once daily, usually at bedtime) + 50% as bolus (divided equally into 3 pre-meal doses of rapid-acting insulin).
3
Add correction scale: Give correction dose ON TOP of scheduled mealtime bolus based on pre-meal BG. Use low/medium/high scale based on insulin sensitivity (see table below).
4
Reassess daily: If BG consistently > 180 mg/dL, increase TDD by 10–20%. If hypoglycemia occurs, decrease TDD by 20%. Adjust basal vs bolus based on fasting vs post-meal patterns.
Correction Scale (Sliding Scale Add-On)
Low scale: insulin-sensitive, elderly, CKD, hepatic. Medium scale: most patients. High scale: insulin-resistant, obese, on steroids, TDD > 80 units.
Blood Glucose (mg/dL)
Low Dose
Medium Dose
High Dose
150–199
1 unit
2 units
3 units
200–249
2 units
3 units
5 units
250–299
3 units
5 units
7 units
300–349
4 units
7 units
9 units
> 350
5 units + notify MD
8 units + notify MD
11 units + notify MD
Who Gets Which Scale?
The correction scale is NOT one-size-fits-all. Choosing the wrong scale causes hypoglycemia (too aggressive) or persistent hyperglycemia (too conservative). Match the scale to the patient's insulin sensitivity.
May still need even MORE. If BG stays > 300 on high scale, increase correction by 50% or add standing bolus doses.
Steroid-Induced Hyperglycemia -Special Protocol
Steroids cause the WORST inpatient hyperglycemia. Prednisone 40 mg can push BG to 400+ in diabetics. Most steroid hyperglycemia peaks 8–12 hours after the dose (afternoon/evening for AM steroids). Standard sliding scales are often insufficient.
1
Always use HIGH-DOSE correction scale for any patient on ≥ 20 mg prednisone equivalent (or dexamethasone ≥ 4 mg, methylprednisolone ≥ 16 mg, hydrocortisone ≥ 80 mg).
2
Add NPH insulin with AM steroids: NPH peaks at 4–12h, matching the steroid-induced glucose rise. Start at 0.1 units per mg of prednisone (e.g., prednisone 40 mg → NPH 4 units with AM dose). Titrate aggressively -most patients need 0.2–0.4 units/mg.
3
For dexamethasone (long-acting steroid): Hyperglycemia lasts 24–36h. Use glargine (not NPH) since dex effect is longer. Increase basal insulin by 20–40%. High-dose correction scale around the clock.
4
For pulse-dose steroids (methylprednisolone 1g/day): These patients WILL have BG 300–500+. Start insulin drip protocol if BG > 300 × 2 consecutive checks. Regular insulin drip 0.05–0.1 units/kg/hr. BG checks q2h.
5
When tapering steroids → taper insulin proportionally. As prednisone decreases, reduce NPH/correction scale. Failure to reduce insulin during steroid taper = hypoglycemia. Match insulin to current steroid dose daily.
Steroid
Equivalent Dose
Duration of BG Effect
Insulin Strategy
Prednisone (Deltasone) / Prednisolone (Orapred)
40 mg PO daily
12–16h (peaks afternoon)
NPH with AM dose. Start 0.1 units/mg, titrate to 0.2–0.4 units/mg. High-dose correction.
Methylprednisolone (Solu-Medrol)
32 mg IV daily
12–18h
NPH or increase basal 20%. High-dose correction. If pulse dose (1g) → insulin drip.
Dexamethasone (Decadron)
6 mg PO/IV daily
24–36h (long-acting)
Increase glargine 20–40%. High-dose correction around the clock. NPH won't cover -too short.
Hydrocortisone (Solu-Cortef)
80 mg IV daily
8–12h per dose
If q8h dosing → moderate hyperglycemia. Medium or high scale. Add NPH 2–4 units per dose if BG > 250.
Non-diabetic on steroids? Up to 50% of patients on high-dose steroids develop new hyperglycemia. Check BG at least QID (before meals + bedtime). If BG > 180 × 2 → start correction scale. Many will need scheduled insulin.
Diabetic on steroids? Their home insulin is NEVER enough. Increase TDD by 30–50% immediately when starting steroids. Don't wait for BG to spiral. Proactive dosing prevents glucose roller-coasters.
The #1 mistake: Using sliding scale ALONE for steroid patients. Correction-only dosing chases glucose after it's already sky-high. These patients need scheduled NPH or increased basal insulin PLUS high-dose correction scale.
DKA Insulin Drip Protocol
Do NOT start insulin if K⁺ < 3.5 mEq/L. Insulin drives K⁺ intracellularly and will cause fatal arrhythmia. Replete potassium first.
1
Check K⁺ BEFORE insulin: If K⁺ < 3.5 → hold insulin, replete with 20–40 mEq/hr KCl IV. Recheck in 1–2 hours. Do NOT proceed until K⁺ ≥ 3.5.
2
Start regular insulin drip: 0.1 units/kg/hr continuous IV infusion. No initial bolus preferred (ADA 2026). Only regular insulin can be given IV.
3
Check BG hourly. Target BG drop: 50–70 mg/dL per hour. If BG not dropping by ≥ 50 mg/dL/hr, double the drip rate. If dropping > 100 mg/dL/hr, halve the rate.
4
When BG < 200 mg/dL: Start D5 ½NS and reduce insulin drip to 0.02–0.05 units/kg/hr. Continue drip until anion gap closes -NOT just until BG normalizes.
5
Transition to SQ insulin when ALL met: BG < 200 AND anion gap ≤ 12 AND bicarb ≥ 15 AND pH > 7.3. Give long-acting SQ insulin (glargine 0.25 units/kg) 2 hours BEFORE stopping drip to prevent rebound DKA.
Hypoglycemia Protocol
BG < 70 mg/dL (alert, able to eat): Give 15g fast-acting carbohydrates -4 oz juice, 4 glucose tabs, or 1 tbsp honey. Recheck BG in 15 minutes. Repeat if still < 70. Follow with complex carb/protein snack once BG > 80.
BG < 50 mg/dL or unable to eat: D50 25 mL IV push (12.5 g dextrose). Flush line. Recheck BG in 15 minutes. May repeat once. Start D10 drip if recurrent.
BG < 40 mg/dL or altered mental status: D50 50 mL IV push (25 g dextrose). If no IV access → glucagon 1 mg IM/SQ. Position patient on side (glucagon causes nausea). Recheck BG q15 min.
After any episode: Hold ALL scheduled insulin doses. Investigate cause (missed meal, renal decline, medication error, sepsis). Reduce TDD by 20–40%. Document and notify attending.
Key Clinical Pearls
Never use sliding scale alone -always pair correction insulin with a scheduled basal insulin. Sliding scale monotherapy leads to roller-coaster glucose and worse outcomes.
NPO patients still need basal insulin -reduce basal dose by 20–50% but do NOT hold entirely. Basal insulin suppresses hepatic glucose output and prevents DKA in type 1 diabetics.
Steroid-induced hyperglycemia peaks in the afternoon -use NPH insulin with morning steroids (onset matches steroid-induced glucose rise). Dose: 0.1 units per mg of prednisone equivalent.
TPN patients: Add regular insulin directly to TPN bag at 0.1 units per gram of dextrose as starting dose. Titrate based on BG monitoring q6h.
Renal adjustment: Reduce TDD by 25% if GFR 10–30 mL/min. Reduce TDD by 50% if GFR < 10 or on dialysis. Insulin clearance is markedly reduced in advanced CKD.
Always check K⁺ before starting insulin in any clinical setting -insulin shifts potassium intracellularly. This applies to DKA, hyperkalemia treatment, and routine dosing in CKD patients.
Insulin stacking: Rapid-acting insulin lasts 3–5 hours. Avoid re-dosing correction insulin within 3 hours to prevent hypoglycemia from dose overlap.
Transition from drip to SQ: The 2-hour overlap is critical. Stopping the drip without SQ coverage causes rebound hyperglycemia/ketosis within 1–2 hours.
🧮 Insulin Calculator
Method 1 -From Sliding Scale Usage
Add up all sliding scale insulin given in the past 24h.
Method 2 -Weight-Based (Insulin-Naive)
For patients not previously on insulin or no sliding scale data available.
Scenario
Recommendation
Patient eating normally
Full basal-bolus-correction: 50% basal (glargine QHS) + 50% nutritional (lispro AC meals) + correction scale
NPO
Continue basal (reduce 20–50% if concerned). Hold nutritional. Correction-only q6h. Never hold basal completely in Type 1.
Tube feeds (continuous)
Basal (glargine) + correction q6h. Or NPH q12h + correction. Or 70/30 insulin q12h.
On steroids
↑ TDD by 20–40%. Steroids cause afternoon/evening hyperglycemia → increase lunch and dinner doses more than basal.
Transitioning from drip
24h drip total × 80% = TDD. Split 50/50. Give SubQ basal 2–4h BEFORE stopping drip.
Correction factor
1800 ÷ TDD = how many mg/dL 1 unit drops glucose.
Quick Reference
ACLS Algorithms & Code Timer
Cardiac arrest protocols, drug dosing, and your Code Clock app for real-time code documentation.
⏱️
Code Clock App
Real-time code documentation with CPR tracking, medication logging, and automatic timing. Opens in a new tab.
Atropine 1 mg IV q3–5 min (max 3 mg). Ineffective in transplanted hearts (denervated) and infra-nodal block (Mobitz II, 3rd degree).
If Atropine Fails
Transcutaneous pacing -apply pads, set rate 60–80, increase mA until capture. Sedate if conscious. OR dopamine 5–20 mcg/kg/min or epinephrine 2–10 mcg/min infusion as bridge.
Definitive
Transvenous pacing for persistent symptomatic bradycardia. Cardiology consult for permanent pacemaker if underlying cause is irreversible (complete heart block, SSS).
Tachycardia with Pulse -Algorithm
Unstable (hypotension, AMS, chest pain, acute HF)? → Synchronized cardioversion immediately. Do not delay for diagnosis.
Rhythm
Width
Treatment
SVT (regular narrow)
Narrow (< 120 ms)
Vagal maneuvers → adenosine 6 mg → 12 mg. If refractory: diltiazem or cardioversion. (The old 6-12-12 sequence is superseded; AHA lists two doses.)
Afib/Aflutter (irregular narrow)
Narrow
Rate control: diltiazem or metoprolol. If unstable: cardioversion. See Afib with RVR topic.
Monomorphic VT (regular wide)
Wide (> 120 ms)
Stable: amiodarone 150 mg IV over 10 min. Unstable: synchronized cardioversion. If pulseless: defibrillate.
Polymorphic VT / Torsades
Wide, irregular
Magnesium 2g IV. If pulseless: defibrillate (unsynchronized). Stop offending drugs (QTc prolongers). Overdrive pacing.
Wide-complex uncertain
Wide
Treat as VT until proven otherwise. Amiodarone if stable. Cardioversion if unstable. Never give adenosine or CCB to wide-complex tachycardia of unknown origin.
Post-Arrest: ROSC Checklist
12-lead ECG → STEMI → cath lab immediately
SpO₂ target 94–98% -avoid hyperoxia
PaCO₂ target 35–45 -avoid hypocapnia
MAP ≥ 65–70 (norepinephrine first-line)
Targeted temperature management -prevent fever > 37.7°C
Continuous EEG monitoring (seizures in 30–40%)
Full workup: echo, labs, CT head if no clear cardiac cause
Secondary prevention ICD evaluation before discharge -any survivor of VF or hemodynamically unstable VT arrest NOT due to a transient/reversible cause is a Class I indication for ICD. Reversible causes (acute MI with complete revascularization, corrected electrolytes, drug-induced QT, commotio cordis) generally don't qualify. Evidence: AVID 1997, CIDS 2000, CASH 2000.
→ See full Post-Cardiac Arrest (ROSC) topic for details
0–10 self-reported scale. Target NRS ≤ 3. Reassess after every intervention.
Key Pearls
Morphine is NOT an ICU drug. Histamine release → hypotension + bronchospasm. M6G accumulates in renal failure. Use fentanyl or hydromorphone instead.
Fentanyl is an analgesic first, sedative second. At 25–100 mcg/hr it provides pure analgesia. At 100–200+ mcg/hr it adds sedation. Many patients need nothing else -this is "analgo-sedation."
Before escalating sedation, always reassess pain. CPOT ≥ 3 or NRS ≥ 4 means the patient needs more analgesia, not more propofol.
Gabapentin in CKD = #1 iatrogenic AMS. Always renal-dose. If a CKD patient on gabapentin becomes altered, check the dose before ordering a head CT.
→ For sedation agents, RASS targets, and special situations, see Sedation Guide
Quick Reference
Sedation Guide
Add sedation ONLY after adequate analgesia. Target lightest effective sedation -deep sedation kills ICU patients. PADIS, 2018
Have you treated pain first? Before reaching for a sedative, ensure fentanyl (or equivalent) is optimized. If CPOT ≥ 3 → the patient needs more analgesia, not sedation. Go to Analgesia Guide.
Sedation Agent Comparison
Agent
Dose
Onset
Best For
Avoid When
Key Side Effects
Propofol (Diprivan) (Diprivan) 1ST LINE
5–50 mcg/kg/min IV
30–60 sec
Most ventilated ICU patients. Rapid on/off -ideal for daily SAT, neuro checks.
Hypotensive patient needing sedation → Ketamine (supports BP). Or low-dose propofol with vasopressor support.
Alcohol/benzo withdrawal → Benzodiazepines (CIWA-guided). Phenobarbital for severe/refractory. Add dex as adjunct.
Severe ARDS + NMB → Deep sedation (RASS −3 to −4). Propofol or midazolam + fentanyl. Ensure adequate analgesia -paralyzed patients cannot communicate pain.
Procedural sedation → Propofol 0.5–1 mg/kg bolus ± fentanyl. Etomidate for cardioversion. Ketamine for hemodynamically unstable procedures.
Key Pearls
Light sedation saves lives. RASS −1 to 0 reduces ICU mortality, ventilator days, and long-term cognitive impairment vs deep sedation. There is almost never a reason for RASS −4/−5 without NMB.
Benzos cause delirium. Midazolam and lorazepam are independently associated with ↑ delirium and ↑ mortality compared to propofol or dexmedetomidine MENDS, 2007SEDCOM, 2009. Never use as first-line ICU sedation.
Dexmedetomidine is the only sedative without respiratory depression. Can sedate non-intubated patients (post-extubation agitation, NIV patients, procedural sedation).
Daily SAT + SBT. Every day ask: can we turn off sedation? Can we do a breathing trial? The ABCDEF bundle reduces mortality and delirium. Do it every single day.
Propofol Infusion Syndrome (PRIS) - Why It Happens
Pathophysiology - mitochondrial energy failure
Big picture: propofol is a mitochondrial toxin. Mitochondrial dysfunction means cells can't make ATP. The tissues that burn the most ATP at baseline are the ones that fail first, and the syndrome's clinical features map directly onto them:
Heart (high-throughput ATP for contraction + conduction) → cardiac failure, Brugada-pattern ECG, refractory bradycardia, asystole.
Renal tubules (ATP-hungry Na⁺/K⁺ ATPase along the nephron) → acute kidney injury, both from direct tubular ATP failure and from pigment nephropathy as myoglobin pours in.
System-wide: when aerobic metabolism fails everywhere, lactate climbs and a new anion-gap metabolic acidosis appears. That's the lab signal that the rest of the syndrome is already in motion.
Two-pronged mitochondrial hit: propofol blocks how cells use fat for fuel (fatty-acid β-oxidation) and disrupts the mitochondrial energy chain itself, so ATP production collapses.
The lipid vehicle adds fuel mitochondria can't burn: the 10% intralipid emulsion delivers a continuous fat load that the impaired mitochondria can't process. Triglycerides climb, plasma turns lipemic, free fatty acids accumulate.
Direct cardiac toxicity is separate from the energy failure: propofol independently blocks cardiac Na⁺ channels, L-type Ca²⁺ channels, and β-adrenergic receptors. This is why the bradycardia is refractory to atropine and catecholamines, and why the ECG develops a Brugada pattern.
What makes PRIS more likely (and why)
High dose (> 4 mg/kg/hr) and long duration (> 48 h) - the two strongest predictors. More drug for longer = more mitochondrial toxin delivered. These are also the defining criteria for "high risk" in nearly every PRIS case series.
Concurrent catecholamine infusions (norepinephrine, epinephrine, phenylephrine) - adrenergic stimulation drives cellular ATP demand sky-high at exactly the moment damaged mitochondria can't supply it. Worse, propofol is blocking the β-receptor, so the pressor dose keeps climbing to no effect, a vicious cycle that masks early shock.
High-dose glucocorticoids (stress-dose hydrocortisone, dexamethasone for cerebral edema, etc.) - steroids independently impair mitochondrial function and increase catabolic load. Almost always co-administered with catecholamines in the patients who get PRIS, so risk stacks.
Sepsis - septic cells already have cytopathic hypoxia (mitochondrial dysfunction with normal oxygen delivery). Propofol pushes a mitochondrial system that's already failing right over the edge.
Severe traumatic brain injury - the classic at-risk population. These patients need deep, prolonged propofol for ICP control AND are usually on catecholamines AND often steroids. PRIS was first described in this group; treat it as the prototype red-flag scenario.
Starvation, low-carb, or ketogenic state - when cells can't use glucose, they fall back on fatty-acid β-oxidation for energy. But that's exactly the pathway propofol blocks. The backup generator is offline.
Young age - pediatric mitochondria are more vulnerable to fatty-acid overload, and propofol clearance differs in kids. PRIS was first recognized in critically ill children; still happens in adults but pediatric ICU patients are highest risk per mg of drug delivered.
Inborn fatty-acid oxidation defects (MCAD, VLCAD, carnitine deficiency) - the β-oxidation pathway is already broken at baseline; even modest propofol doses can trigger the syndrome. Rare but a classic board point.
Clinical presentation - the diagnostic constellation
The lab signature: a new high anion-gap metabolic acidosis with elevated lactate in a patient on a propofol drip - without shock, sepsis, or another perfusion failure to explain it - is PRIS until proven otherwise. This is Type B2 (mitochondrial) lactic acidosis, not Type A (hypoperfusion). It does not respond to fluid or pressors, because perfusion is not the problem.
High anion-gap lactic acidosis - cells can't oxidize pyruvate, so it shunts to lactate. AG widens, bicarb drops. Often the first lab abnormality, before CK or TGs move.
Hyperkalemia - K⁺ pours out of dying muscle cells. Stacks arrhythmia risk on top of the existing cardiac toxicity.
Hypertriglyceridemia + lipemic plasma - the lipid emulsion accumulates because mitochondria can't process it. TGs often > 500-1000 mg/dL; the lab will note grossly lipemic samples.
Acute kidney injury - dual hit: myoglobin causes pigment nephropathy AND tubular ATP failure stops Na⁺/K⁺ ATPase. Often oliguric.
Cardiac dysfunction - new bradycardia refractory to atropine and pressors, falling BP, reduced contractility on echo. Brugada-pattern ECG develops on the way to collapse (see next).
PRIS is a clinical diagnosis - you don't need every feature. Any 2-3 of the above in a patient on propofol > 24-48 h is enough to stop the drug and start workup.
Cardiac / conduction signature - Brugada-pattern ECG is the most common finding
Type 1 Brugada-like ECG (coved ST elevation > 2 mm in V1-V3 with T-wave inversion) is the most common and most characteristic conduction finding in PRIS, and frequently appears before circulatory collapse. Mechanism: propofol's dose-dependent cardiac sodium-channel blockade unmasks a Brugada phenotype. If you see this on a propofol drip, stop propofol now - do not wait for lactate or CK to confirm.
Early: Brugada-pattern ST elevation V1-V3, new RBBB, PR/QRS prolongation.
Mid: refractory bradycardia (atropine- and catecholamine-resistant), QT prolongation.
Terminal: ventricular tachyarrhythmias, asystole.
Monitoring on a propofol drip
Send these on anyone running propofol > 4 mg/kg/hr OR > 48 h. Tighter cadence if other risk factors (catecholamines, steroids, sepsis, TBI) are stacked on top.
BMP daily - K⁺, anion gap, bicarb, Cr. A widening AG or new acidosis is the earliest red flag.
Lactate daily - a rising lactate without obvious shock is the key warning sign that mitochondria are failing.
Triglycerides q48h - TGs > 400-500 mg/dL signal the lipid emulsion is overwhelming damaged mitochondria.
CK q24-48h - rising CK = rhabdo starting. Pair with urine myoglobin if elevated.
ECG - baseline at drip start; recheck with any new bradycardia, conduction abnormality, or hemodynamic change. Look specifically for Brugada-pattern ST elevation in V1-V3.
Treatment - stop the drug, support the organs
STOP propofol immediately the moment PRIS is suspected. This is the only intervention that reverses the mitochondrial toxicity - everything else is supportive. Do not wait for confirmatory labs. Switch sedation to dexmedetomidine, midazolam, or ketamine.
Remove the cofactors - wean catecholamines if hemodynamics allow, taper steroids, address starvation/low-carb state, treat sepsis aggressively. These amplified the toxicity in the first place.
Hemodynamic support - expect catecholamine-refractory bradycardia and hypotension (propofol has blocked the β-receptor and Na⁺/Ca²⁺ channels). Use transvenous pacing for symptomatic bradycardia. Isoproterenol or glucagon can be tried for refractory β-receptor failure (case-report level).
Bicarbonate for severe acidosis (pH < 7.1) as a bridge to renal replacement - the underlying problem won't resolve until propofol clears.
CRRT / hemodialysis for refractory acidosis, hyperkalemia, AKI, or severe hypertriglyceridemia - also clears propofol and lactate. Strongest case-series support among rescue interventions.
V-A ECMO for refractory cardiogenic shock - bridges the patient while the mitochondrial toxicity resolves. Case reports support survival with timely cannulation.
Mortality 30-50% once the full syndrome develops, and survival correlates directly with how fast propofol was stopped. When in doubt, switch sedation - the cost of being wrong about PRIS is much lower than the cost of being right and slow.
Special Clinical Scenarios
Alcohol / Benzodiazepine Withdrawal
Benzodiazepines are the treatment -NOT propofol or dexmedetomidine alone.
CIWA-Ar score q4–8h -score > 8 → treat
Lorazepam 1–4 mg IV q1h PRN (symptom-triggered) OR diazepam 5–20 mg PO/IV PRN
Severe/refractory (CIWA > 20): phenobarbital 130–260 mg IV q15–30 min until controlled
Add dexmedetomidine as adjunct for autonomic symptoms (tachycardia, HTN)
Thiamine 100 mg IV before any glucose (prevents Wernicke's)
Delirium Management
Non-pharmacologic first: reorientation, day/night cycle, early mobility, hearing aids/glasses
Dexmedetomidine -reduces delirium duration vs benzos MENDS, 2007
Midazolam 1–2 mg IV + fentanyl 25–50 mcg (or local only)
Cardioversion
Propofol 0.5–1 mg/kg IV or etomidate 0.2 mg/kg IV
Paracentesis / thoracentesis
Topical lidocaine only; add midazolam if anxious
Pimp Questions
What is propofol infusion syndrome and how do you recognize it?
Rare but fatal complication of high-dose (> 4 mg/kg/hr) or prolonged propofol. Caused by impaired mitochondrial fatty acid oxidation. Features: new metabolic acidosis + elevated lactate, rhabdomyolysis, hyperkalemia, lipemic plasma, Brugada-like ECG, cardiac failure. Treatment: stop propofol immediately, switch agent, supportive care.
Why are benzodiazepines associated with worse ICU outcomes?
MENDS, 2007SEDCOM, 2009: more delirium, longer ventilator time, increased ICU stay vs propofol or dexmedetomidine. Accumulate in renal/hepatic failure. Paradoxical agitation in elderly. Reserve for withdrawal and status epilepticus only.
What makes dexmedetomidine unique compared to other sedatives?
Only ICU sedative without respiratory depression. Mechanism: α₂ agonism (locus coeruleus) → sleep-like state, patients arouse easily. Can sedate non-intubated patients, continue during vent weaning, and doesn't interfere with respiratory drive during SBT.
EmergentICU
Acute Exacerbation of COPD (AECOPD)
Sustained worsening of dyspnea, cough, or sputum beyond normal day-to-day variation. NIV before intubation. Bronchodilators + steroids are the backbone. Find and treat the trigger. For chronic / outpatient COPD management (GOLD staging, ABE classification, inhaler step-up, biologics), see COPD Chronic Management.
↪
Also see:COPD Chronic Management (GOLD 2026) for outpatient staging, ABE classification, inhaler step-up, and biologic candidacy.
🔍 Overview
What changed in GOLD 2026 (acute-care relevant points):(1) Pulmonary rehab within 4 weeks post-exacerbation strongly emphasized, reduces 1-year mortality and rehospitalization, plan it before discharge. (2) Biologics for severe eosinophilic COPD (mepolizumab, benralizumab, dupilumab) if blood eos ≥ 300 + frequent exacerbations on triple therapy, refer to outpatient pulm at discharge. (3) ICS without LABA is not appropriate, if you're discharging on inhaled steroid, pair it with LABA. Full GOLD 2026 changes (chronic).
Definition
AECOPD is a sustained worsening of respiratory symptoms -increased dyspnea, cough frequency, and/or sputum production (volume, purulence) -beyond normal day-to-day variation, requiring a change in therapy. Anthonisen 1987
This is the most common cause of COPD-related morbidity and mortality. Frequent exacerbators (≥ 2 per year) have accelerated lung function decline and reduced survival. ICU mortality ranges from 10–30%.
Severity Classification: Mild (bronchodilators only) | Moderate (requires antibiotics ± steroids) | Severe (hospitalization) | Very Severe (ICU admission)
Air stacking creates intrinsic PEEP (auto-PEEP), forcing patients to breathe against their own trapped air. This is why you see tripod positioning, pursed-lip breathing, and accessory muscle recruitment -they're desperately trying to empty their lungs before the next breath.
Common Precipitants of AECOPD
Work through this list in every admission, and note the right-hand column: some of these precipitate a true exacerbation, while others ARE the diagnosis instead of it. That distinction changes what you treat. The six alternative diagnoses are set out as the 6 P's in the next section.
#
Cause
Details
Precipitant, or the diagnosis itself?
1
Pneumonia / Pulmonary infection
Most common trigger. Viral ~50% (rhinovirus, influenza, RSV, parainfluenza). Bacterial ~30% (H. influenzae, S. pneumoniae, M. catarrhalis).
Both. An airway infection precipitates a true exacerbation, but an infiltrate on imaging means pneumonia rather than AECOPD
2
Pulmonary embolism
~12% prevalence across hospitalized AECOPD overall; ~16% in unexplained AECOPD (Aleva meta-analysis 2017). Often missed. Always consider if no clear infectious trigger, pleuritic pain, unexplained tachycardia, or hypoxia out of proportion.
The diagnosis itself. A PE does not set off an exacerbation, it explains the breathlessness
3
Pneumothorax
Especially in emphysematous patients with bullae. CXR mandatory on all AECOPD admissions.
The diagnosis itself
4
Pleural effusion
Can worsen dyspnea and restrict lung expansion. Rule out on CXR.
The diagnosis itself
5
Poor compliance
Missed inhalers (LAMA/LABA/ICS non-adherence) -very common and modifiable. Always ask about medication use.
Precipitant
6
Pollution / environmental
PM2.5, ozone spikes, cold air, biomass fuel smoke, occupational dust. Leading cause of COPD in low-income countries (biomass > smoking). Both a cause of COPD development and a trigger for exacerbations.
Precipitant
Don't Miss PE: PE occurs in ~12% of AECOPD hospitalizations overall (~16% in unexplained AECOPD) per Aleva meta-analysis 2017. Consider CTPA if: no clear infectious trigger, pleuritic pain, unexplained tachycardia, or hypoxia out of proportion to exam findings.
Also consider: temperature extremes, and drugs (below). Heart failure, ACS or arrhythmia, and mucus plugging or aspiration are covered as Pump, Pulse and Plug in the 6 P's below, since each is an alternative diagnosis rather than a precipitant.
Common Mistake: Non-selective beta-blockers (propranolol, carvedilol), sedatives/opioids, and ACE inhibitors can trigger or worsen AECOPD. Always review the med list -ACE-inhibitor cough is frequently misdiagnosed as an exacerbation.
The 6 P's -Mimics of AECOPD
This is the 6 P's on this page. They are the alternative diagnoses, meaning what else could be causing the breathlessness, and they are deliberately kept separate from the precipitants listed above. Pneumonia, PE and pneumothorax appear in both places, because an airway infection can precipitate a true exacerbation while an infiltrate, clot or air leak is the diagnosis instead of it. Either way you have to go looking.
The reasoning is inherently subtractive: dyspnea + known COPD + nothing else explains it = exacerbation. AECOPD is a diagnosis of exclusion, so these are the six you must clear.
#
P
Suspect it when
Why it matters
1
PE
No infectious prodrome, pleuritic pain, hypoxemia out of proportion to the wheeze, or poor response to bronchodilators
The highest-yield miss. Roughly 1 in 6 hospitalized patients with an unexplained exacerbation (pooled 16.1%), and 68% of those emboli were main, lobar or interlobar, so it is not subsegmental noise. Aleva, Chest 2017
2
Pneumonia
Fever, focal consolidation, higher CRP
An infiltrate makes it pneumonia with COPD, not AECOPD: different antibiotic duration, different steroid logic, higher mortality
3
Pneumothorax
Sudden pain, unilateral signs, sudden deterioration on NIV
Bullous disease makes it disproportionately common and easy to miss on a portable film. Look before applying positive pressure, which can convert it to tension
4
Pump failure
Orthopnea, elevated JVP, edema, raised BNP
COPD and HFpEF overlap heavily in the same smoker. BNP is blunted by obesity and raised by cor pulmonale, so it helps but does not settle it. Diurese rather than escalate bronchodilators
5
Pulse
Irregular pulse, tachycardia that will not settle, chest pain or ischemic ECG change
ACS or a new arrhythmia (AF, atrial tachycardia, MAT). Demand ischemia and tachyarrhythmia both present as "I cannot breathe", and beta-agonists aggravate the arrhythmias
6
Plug / aspiration
Abrupt onset, lobar collapse, asymmetric air entry, or a choking or reduced-consciousness event
Mucus plugging, foreign body, aspiration or an upper airway process. The problem is the airway itself rather than the small airways, so bronchodilators will not fix it
BNP / NT-proBNP -exclude heart failure as trigger or co-contributor
Troponin if cardiac involvement suspected
ABG Interpretation in AECOPD
Pattern
pH
PaCO₂
HCO₃
Interpretation
Acute hypercapnia
< 7.35
> 45
Normal / mildly ↑
Acute exacerbation -treat aggressively
Chronic compensated
7.35–7.45
> 45
↑↑ (≥ 30)
Stable CO₂ retainer -know their baseline
Acute-on-chronic
< 7.35
> 45 (above baseline)
↑↑
Most common pattern -compensated chronically + acute decompensation
pH < 7.25
< 7.25
> 60
↑
Severe -NIV now, low threshold for intubation
CO₂ Retainer Pearl: Chronic CO₂ retainers have high HCO₃ as compensation. A "normal" PaCO₂ of 45 mmHg may represent acute decompensation in someone whose baseline is 60 mmHg. Always compare to prior ABG or clinic notes.
Sputum & Microbiology
Sputum Gram stain + culture if purulent sputum and no recent culture data
Respiratory viral panel (if influenza season -guides oseltamivir)
Legionella urine antigen + Pneumococcal urine antigen if severe / ICU
Procalcitonin -helps distinguish bacterial vs viral trigger PRORATA 2010
Consider CTPA if PE not excluded (atypical presentation, no clear infectious trigger)
Spirometry -Don't Do It Acutely
Do NOT perform spirometry during an acute exacerbation. Results are unreliable, the maneuver is uncomfortable, and it can worsen respiratory distress. Review prior PFTs in the chart for baseline FEV₁ context.
For chronic COPD baseline classification (GOLD Stage 1-4 by FEV₁ % predicted, GOLD ABE groups by symptoms + exacerbation history, inhaler step-up, biologics for eosinophilic phenotype), see the COPD Chronic Management topic. The acute exacerbation workflow below focuses on managing THIS event -not setting outpatient maintenance therapy.
🚨 Management
Don't Confuse the Protocol with Acute Asthma
⚠️ Same drugs, different protocol. Treating an AECOPD patient like an asthmatic (q20 min × 3 albuterol + 100% O₂) induces hypercapnia and hypoxic-drive crash. The first three decisions diverge:
YES if Anthonisen ≥ 2 of 3 (↑ dyspnea, sputum volume, sputum purulence)
Usually NO
NIV
First-line for hypercapnic exacerbation (strong evidence, > 80% avoid intubation)
Bridge only, low threshold to intubate
IV magnesium
Not standard, weak evidence
2 g IV for severe (3Mg)
Decompensation tempo
Days
Hours
What's the same: dose per neb (albuterol 2.5–5 mg, ipratropium 0.5 mg), DuoNeb formulation, steroid burst with no taper if ≤ 5 days, sit upright. Full asthma acute protocol →
Management Algorithm
Immediately -Controlled Oxygen
Target SpO₂ 88–92% -and equally important: do NOT exceed 92% in known or suspected CO₂ retainers. Austin 2010
Why the upper limit matters:
Haldane effect -Dominant mechanism (~70%). Oxygenated Hb offloads CO₂ into plasma → PaCO₂ rises independent of respiratory rate.
V/Q mismatch -High FiO₂ abolishes hypoxic pulmonary vasoconstriction → blood flows to poorly-ventilated units → worsened dead space.
Practical approach: Start 1–2L NC, titrate to SpO₂ 88–92%. Check ABG within 30–60 min. If PaCO₂ rising despite target SpO₂ → escalate to NIV, not more O₂.
Common Error: Placing COPD patient on 15L NRB → arrives with PaCO₂ 90, pH 7.15. SpO₂ 100% is not reassuring in COPD -it may be the problem.
Bronchodilators -First-Line Treatment
Short-acting β₂ agonist (SABA) + short-acting muscarinic antagonist (SAMA) via nebulizer. Albuterol (Ventolin) 2.5–5 mg + ipratropium (Atrovent) 0.5 mg neb q1h × 1–2 if severe, then scheduled q4–6h (or DuoNeb [albuterol + ipratropium pre-mix] combination, same schedule). Do NOT use the asthma q20 min × 3 loading regimen, AECOPD doesn't need it and chronic patients tolerate intermittent dosing better.
Continue ipratropium throughout admission (unlike asthma where it's stopped after 3 doses).
MDI + spacer equally effective as nebulizer in mild-moderate exacerbations (and doesn't aerosolize virus). Turner, 1997
Continuous albuterol nebulizer only if severe bronchospasm not responding to intermittent dosing (less commonly needed in COPD than asthma).
Systemic Corticosteroids
Prednisolone 40 mg PO daily × 5 days -reduces treatment failure and length of stay. REDUCE, 2013 showed 5 days non-inferior to 14 days.
Use IV methylprednisolone 60 mg daily if unable to take PO (NPO, vomiting) -equivalent to prednisone 40 mg PO, same 5-day course, no taper. Do NOT use 125 mg q6h (asthma-style dosing, not GOLD-aligned for AECOPD; lower-dose corticosteroids < 80 mg prednisone-equivalent are non-inferior).
No taper needed for 5-day course. Taper only if > 3 weeks of steroids.
🔄 Updated Practice: Old teaching: 10-14 day steroid course for COPD exacerbation. REDUCE 2013 showed 5 days of prednisone 40mg is non-inferior to 14 days. Shorter course = less hyperglycemia, less immunosuppression, same outcomes. Also: old teaching was to check theophylline levels and use IV aminophylline -this is rarely done anymore due to narrow therapeutic index and better alternatives.
Antibiotics (if indicated)
Antibiotics reduce treatment failure in moderate-severe AECOPD with purulent sputum. Anthonisen 1987 Anthonisen Criteria (all 3 = definitely treat; 2/3 = probably treat; 1/3 = no benefit):
① Increased dyspnea ② Increased sputum volume ③ Increased sputum purulence
Empiric choice: Amoxicillin-clavulanate 875/125 mg PO BID OR doxycycline 100 mg BID × 5–7 days. Levofloxacin if Pseudomonas risk (structural lung disease, frequent hospitalization, recent abx).
RSI with cautious ventilator settings to avoid auto-PEEP.
Initial vent: TV 6–8 mL/kg PBW, RR 10–12/min (lower than ARDS!), I:E 1:3 or 1:4, PEEP 5 cmH₂O. Low RR = more time for exhalation = less air trapping.
If hemodynamic collapse after intubation → disconnect ETT → manual exhalation (auto-PEEP release).
Check plateau pressure + perform expiratory hold for intrinsic PEEP measurement.
NIV Success vs Failure
Parameter
Good Response (1–2h)
NIV Failure → Intubate
pH
Improving toward 7.35
pH < 7.25 or worsening
PaCO₂
Decreasing
Rising despite NIV
RR
Decreasing
Still > 30 after 1–2h
HR
Decreasing
Worsening tachycardia
Mentation
More alert, cooperative
Worsening confusion, agitation
Accessory muscles
Decreasing
Unchanged or increasing
Discharge Criteria & Optimization
Able to use inhalers correctly
Needs bronchodilators no more frequent than q4h
On room air or at baseline O₂ requirement
Able to eat and sleep without significant dyspnea
Clinically and hemodynamically stable for 12–24h
Maintenance therapy optimized (LAMA + LABA ± ICS reviewed and prescribed)
Smoking cessation counseling
Pulmonary rehab referral
Follow-up within 1–4 weeks
Swipe for more examples
📋 Case 1, Standard AECOPD Management
Patient: 68M with severe COPD (FEV1 35%), presents with worsening dyspnea × 3 days, productive cough with purulent sputum, RR 28, SpO₂ 86% on RA.
Immediate: O₂ via nasal cannula → target SpO₂ 88–92% (NOT 100% -risk of CO₂ retention in COPD). Start BiPAP if not improving (IPAP 12, EPAP 5).
Ventilator settings: Low RR (10–12), TV 6–8 mL/kg PBW, long expiratory time (I:E ratio 1:4 or 1:5) to prevent auto-PEEP/breath-stacking.
Watch for auto-PEEP: If hypotension post-intubation → disconnect from vent for 10 seconds (releases trapped air). Most common cause of post-intubation hypotension in COPD.
Ongoing: Nebs via vent circuit. IV steroids (methylprednisolone 60 mg IV daily = prednisone 40 mg PO equivalent; transition to PO when able, 5-day total course, no taper). Antibiotics. Daily SBT when improving.
Key lesson: COPD + intubation = low rate, long expiratory time, watch for auto-PEEP. Post-intubation hypotension → disconnect and let air out before reaching for pressors.
📋 Case 3, AECOPD vs Pneumonia vs PE Overlap
Patient: 70M with moderate COPD, presents with dyspnea × 2 days, low-grade fever 38.2°C, HR 108, SpO₂ 89%. Treated as AECOPD with steroids, nebs, azithromycin. Not improving at 48h.
Re-evaluation:
CXR: Right lower lobe infiltrate → pneumonia, not just AECOPD. Need broader antibiotics.
D-dimer: 1,850 (elevated). Given immobility + tachycardia out of proportion → CTPA ordered → subsegmental PE found.
Procalcitonin: 0.8 → supports bacterial infection. Confirms need for antibiotics.
Revised treatment:
Upgrade antibiotics: Ceftriaxone 1g IV daily + azithromycin 500mg IV daily (CAP coverage).
Anticoagulation for PE: Heparin drip → transition to apixaban once stable.
Key lesson: When AECOPD doesn't improve in 48h → think beyond COPD. Get a CXR (pneumonia?), consider PE (especially if tachycardia out of proportion), and check procalcitonin. COPD patients often have overlapping diagnoses.
📋 Case 4, AECOPD with Pneumothorax
Patient: 62M with emphysema, sudden onset of severe dyspnea and pleuritic chest pain. SpO₂ 82%. Absent breath sounds on the right. Trachea midline.
CXR: Large right-sided pneumothorax (~40%). No mediastinal shift (simple pneumothorax, not tension, yet).
Why this matters in COPD:
COPD patients have minimal pulmonary reserve, even a small PTX can be life-threatening.
Bullous emphysema predisposes to spontaneous pneumothorax.
BiPAP/CPAP is CONTRAINDICATED with pneumothorax, positive pressure worsens it → tension PTX.
Treatment:
Chest tube (28-32Fr), large PTX in symptomatic COPD patient requires drainage, not observation.
High-flow O₂ (if no CO₂ retention risk) accelerates pleural air reabsorption.
Do NOT start BiPAP until tube is in place and lung is re-expanded.
If recurrent → pleurodesis (chemical or surgical) or VATS referral.
Treat underlying AECOPD concurrently (steroids, nebs, antibiotics if indicated).
Key lesson: Sudden worsening in COPD + absent breath sounds = get a CXR NOW. Rule out pneumothorax before slapping on BiPAP, positive pressure + PTX = tension physiology = cardiac arrest.
📋 Case 5, Frequent Exacerbator: Discharge Planning
Patient: 66F with COPD, 4th hospitalization for AECOPD in the past year. Currently stable on room air, ready for discharge. This is a frequent exacerbator phenotype, high risk of readmission and mortality.
Before discharge, optimization checklist:
Inhaler technique: Watch the patient use their inhalers. Up to 90% use them incorrectly. Teach, re-teach, and verify.
Triple therapy: ICS/LABA/LAMA (e.g., Trelegy Ellipta), reduces exacerbations by ~25% vs dual therapy. Consider if eosinophils ≥ 300.
Azithromycin prophylaxis: 250mg daily or 500mg 3×/week, reduces exacerbation frequency by ~27%. Check ECG (QTc) and hearing before starting. Avoid in NTM risk patients.
Pulmonary rehab referral: Single most impactful intervention for reducing readmissions. Start within 4 weeks of discharge.
Smoking cessation: If still smoking, varenicline (Chantix) + counseling. Only intervention that changes disease trajectory.
Home O₂: If resting SpO₂ ≤ 88% or PaO₂ ≤ 55 on stable state, refer for home O₂ (improves mortality in hypoxemic COPD).
Action plan: Written instructions for when to start prednisone burst + antibiotics at home vs call vs go to ED.
Key lesson: The real COPD management happens at discharge, not during the admission. Optimize inhalers, start prophylactic azithromycin, refer to pulm rehab, and give a written action plan. This prevents the next admission.
💊 Medications & Doses
Bronchodilators
Drug
Class
Dose (Acute)
Notes
Albuterol (Ventolin, ProAir)
SABA
2.5–5 mg neb q1h × 1–2 if severe, then q4–6h scheduled. Continuous 10–15 mg/hr only for refractory bronchospasm.
First-line. Watch hypokalemia and β₂-driven lactic acidosis with frequent dosing. Do NOT use the asthma q20 min × 3 protocol.
Ipratropium (Atrovent)
SAMA
0.5 mg neb q4–6h, continued throughout admission
Combine with albuterol, additive bronchodilation. Less tachycardia. Unlike asthma, ipratropium has sustained benefit in COPD (don't stop after 3 doses).
Albuterol + Ipratropium (DuoNeb)
SABA+SAMA
2.5/0.5 mg neb q1h × 1–2 if severe, then q4–6h scheduled
Single-vial combination, preferred in acute setting for convenience. Same schedule as separate components.
Magnesium sulfate
Smooth muscle relaxant
1.2–2g IV over 20 min
Consider in severe/refractory bronchospasm -evidence mainly from asthma but used in COPD
Corticosteroids
Drug
Dose
Duration
Evidence
Prednisolone (Orapred)
40 mg PO daily
5 days REDUCE, 2013
Non-inferior to 14 days; reduces treatment failure and LOS
Methylprednisolone (Solu-Medrol)
60 mg IV daily (equivalent to prednisone 40 mg PO)
5 days, switch to PO when able. No taper.
Use only if NPO / unable to absorb PO. Avoid 125 mg q6h -asthma-style dosing, not GOLD-aligned for AECOPD. Lower-dose corticosteroids (< 80 mg prednisone-equivalent) non-inferior to higher doses.
Dexamethasone (Decadron)
6 mg IV/PO daily (= prednisone 40 mg equivalent)
5 days, no taper
Alternative; longer half-life, once-daily dosing. Avoid 8 mg -that is ~53 mg prednisone-equivalent, exceeds the GOLD-recommended 40 mg-equivalent target.
Antibiotics
Drug
Dose
Indication
Notes
Amoxicillin-clavulanate
875/125 mg PO BID × 5–7d
First-line moderate AECOPD with purulent sputum
Covers H. influenzae, S. pneumo, M. catarrhalis
Doxycycline (Vibramycin)
100 mg PO BID × 5–7d
Alternative to amox-clav
Good atypical coverage; useful if penicillin allergy
Procalcitonin-Guided Antibiotics: PCT < 0.1 = unlikely bacterial → withhold antibiotics. PCT 0.1–0.25 = equivocal. PCT > 0.25 = bacterial → treat. Reduces antibiotic prescription without affecting clinical outcomes. ProHOSP, 2009 (PRORATA 2010 was an ICU sepsis trial -separate evidence base, do not conflate.)
Maintenance Therapy -Initiate Before Discharge
Drug Class
Example
Notes
LAMA (Long-acting muscarinic antagonist)
Tiotropium (Spiriva) 18 mcg daily
Reduces exacerbation frequency. Most important maintenance drug. UPLIFT, 2008
LABA (Long-acting β₂ agonist)
Salmeterol or Formoterol
Add to LAMA in moderate-severe disease
ICS + LABA
Budesonide/Formoterol
Add ICS if ≥ 2 exacerbations/year or eosinophils ≥ 300. IMPACT, 2018 -triple therapy reduces exacerbations
Roflumilast
500 mcg PO daily
PDE4 inhibitor. Add in severe COPD (FEV₁ < 50%, chronic bronchitis, frequent exacerbations). GI side effects common.
Azithromycin prophylaxis
250 mg 3×/week or 500 mg daily
Reduces exacerbation frequency in former/non-smokers. Albert 2011. Monitor QTc + hearing.
📋 On Rounds
On Rounds
Pimp Questions
Why do we target SpO₂ 88–92% in COPD and not 94–98%?
Three mechanisms, ranked by contribution: (1) Haldane effect (dominant, ~70%) -deoxyHb binds CO₂ ~3.5× more efficiently than oxyHb. Fully saturating Hb with O₂ offloads CO₂ into plasma → PaCO₂ rises even without any change in breathing. (2) V/Q mismatch worsening -high FiO₂ abolishes hypoxic pulmonary vasoconstriction → blood floods poorly-ventilated alveoli → dead space increases → CO₂ retention
What is auto-PEEP and how does it affect management in intubated COPD?
Auto-PEEP (intrinsic PEEP) occurs when air trapping prevents complete exhalation before the next breath is delivered. Gas accumulates → lung hyperinflation → increased intrathoracic pressure → reduced venous return → hemodynamic compromise. Detected by expiratory hold maneuver. Managed by: low RR (10–12/min), prolonged I:E (1:3 to 1:4), low set PEEP (3–5 cmH₂O), bronchodilators, suctioning.
When do antibiotics help in AECOPD and when don't they?
The Anthonisen 1987 landmark trial defined 3 cardinal symptoms: increased dyspnea, increased sputum volume, and increased sputum purulence. Antibiotics benefit patients with all 3 symptoms (NNT ~3–4) or those requiring NIV/intubation. Only 1 symptom present = no antibiotic benefit. Procalcitonin can help guide the decision -PCT < 0.1 suggests viral etiology, withhold antibiotics. PRORATA 2010
NIV vs intubation -when do you escalate?
NIV reduces intubation, mortality, and LOS in hypercapnic AECOPD with pH 7.25–7.35 Brochard 1995. Reassess at 1–2h. Intubate if: pH < 7.25 or worsening, PaCO₂ rising on NIV, RR still > 30, worsening consciousness/agitation, inability to clear secretions, hemodynamic instability. Don't wait too long -a crashing COPD patient is technically difficult to intubate (hyperinflation → hemodynamic instability on intubation).
Clinical Examples
📋 Case 1, Severe AECOPD Requiring NIV
Patient: 68M with GOLD 3 COPD (FEV1 35%), current smoker, presents with 3 days of worsening dyspnea, increased purulent sputum, and confusion. Uses tiotropium and PRN albuterol at home.
Albuterol/ipratropium (DuoNeb) q20min x 3, then q4h. Target SpO2 88-92%Austin, 2010
BiPAP: IPAP 12-14 / EPAP 5, titrate to comfort. Reassess ABG in 1-2h
Prednisone 40 mg PO daily x 5 days (no taper needed) REDUCE, 2013
Antibiotics: amoxicillin-clavulanate (Anthonisen Type 1 -- all 3 cardinal symptoms present)
Teaching point: NIV is the most important intervention in hypercapnic AECOPD (pH 7.25-7.35). The Haldane effect -- not suppression of hypoxic drive -- is the main reason over-oxygenation worsens CO2 retention.
📋 Case 2, Intubated COPD with Auto-PEEP
Patient: 72F with severe COPD, intubated for respiratory failure after failing NIV (pH 7.18, obtunded). 20 minutes post-intubation, BP drops to 70/40, HR rising to 130.
Key findings: Vent settings: AC 16/500/FiO2 60%/PEEP 5. Peak airway pressure 45 cmH2O. Expiratory flow waveform does not return to zero (air trapping). Expiratory hold: intrinsic PEEP 14 cmH2O. Bilateral breath sounds present (not pneumothorax).
Management:
Immediate: disconnect ETT from vent for 30-60 seconds (passive exhalation). BP recovers = confirms auto-PEEP
Adjust vent: decrease RR to 10-12, prolong I:E to 1:4, reduce tidal volume, set extrinsic PEEP to ~80% of measured auto-PEEP
Aggressive bronchodilation: continuous albuterol via in-line nebulizer + IV magnesium 2g
Deep sedation + paralysis if severe air trapping persists (eliminate patient-ventilator dyssynchrony)
Teaching point: Hypotension after intubation in COPD = auto-PEEP until proven otherwise. Disconnecting from the vent is both diagnostic and therapeutic. Three causes of post-intubation hypotension: auto-PEEP, tension pneumothorax, and sedation-induced vasodilation.
📋 Case 3, Mild AECOPD with Discharge Planning
Patient: 58F with moderate COPD (GOLD 2, FEV1 55%), presents with 4 days of increased dyspnea and change in sputum color. No accessory muscle use. Uses albuterol PRN only -- not on any maintenance inhaler.
Doxycycline 100 mg BID x 5 days (Anthonisen Type 2 -- dyspnea + purulence)
Observe 24h. If improving: discharge with prednisone, antibiotic, and albuterol MDI
Critical discharge intervention: Start LABA/ICS maintenance inhaler. Refer for pulmonary rehab. Smoking cessation counseling and NRT
Teaching point: Every AECOPD admission is an opportunity to optimize maintenance therapy and address smoking cessation. Pulmonary rehabilitation is the single most effective non-pharmacologic intervention for reducing future exacerbations.
📋 Sample Presentation
"Mr. Davies is a 67-year-old ex-smoker with GOLD 3 COPD who presented with 3 days of worsening dyspnea, increased purulent sputum, and confusion. On arrival he was in moderate respiratory distress -RR 28, SpO₂ 82% on room air, using accessory muscles. ABG showed pH 7.28, PaCO₂ 78, PaO₂ 52 on 2L NC. CXR showed hyperinflation with no new infiltrate. He was started on albuterol/ipratropium (DuoNeb) nebs, prednisolone 40 mg, and amoxicillin-clavulanate. NIV was initiated -IPAP 14 / EPAP 5 -with SpO₂ target 88–92%. Repeat ABG at 2 hours showed pH 7.34, PaCO₂ 68 -improving on NIV. He is now more alert, RR 20, on NIV cycling with breaks for meals. Today's plan: continue NIV, wean to Venturi mask for meals, antibiotic day 2, maintain O₂ target 88–92%."
Rounds Checklist
SpO₂ 88–92% confirmed? Not on high-flow O₂?
Latest ABG -pH and PaCO₂ trend?
NIV hours per day? Mask tolerance?
Bronchodilator frequency -still q4h? Ready to wean to q6h?
Steroid day #? (5-day course)
Antibiotic day #? (5–7 days). Sputum cultures back?
At 30–60 min after O₂/NIV start, then q4–6h if on NIV
pH improving, PaCO₂ stable or falling
RR, accessory muscle use
q1–2h
RR decreasing; less accessory muscle use = good response
Mental status
q1–2h on NIV
Worsening confusion → intubate
Potassium
q4–6h if frequent nebs
Hypokalemia with frequent albuterol + steroids; replace aggressively
Glucose
q6h if on steroids
Steroid hyperglycemia -use insulin sliding scale
ECG
On admission + PRN
New AF common in AECOPD; rate control with diltiazem or digoxin (avoid BB)
CXR
On admission, repeat if worsening
Exclude new pneumonia, pneumothorax, effusion
NIV Monitoring Checklist
Check ABG 1–2h after starting NIV -if no improvement → escalate
Mask fit -leaks significantly reduce effectiveness
Patient tolerance -sedation is NOT used with NIV (risks aspiration)
Titrate IPAP for TV 6–8 mL/kg and patient comfort
SpO₂ 88–92% while on NIV
Reassess every 2–4h -early identification of NIV failure critical
Ventilator Settings if Intubated
Parameter
Setting
Rationale
Mode
AC/VC
Volume control preferred for predictable TV delivery
Tidal volume
6–8 mL/kg PBW
Lower than ARDS -compliance better but still protect lungs
Rate
10–12 /min (low!)
Low RR = more time to exhale = less auto-PEEP
I:E ratio
1:3 to 1:4
Prolonged expiratory time to reduce air trapping
PEEP
3–5 cmH₂O (low)
Counter auto-PEEP partially; high PEEP worsens hyperinflation
FiO₂
Titrate to SpO₂ 88–92%
Same target as non-intubated
Post-Intubation Hypotension: Severe auto-PEEP → impaired venous return → hemodynamic collapse. Disconnect ETT, allow passive exhalation. Give IV fluid bolus. Reduce RR.
⚡ Summary
Summary
Define It, Then Exclude the 6 P's
Sustained worsening of dyspnea, cough or sputum beyond normal day-to-day variation, and it is a diagnosis of exclusion.The 6 P's are the alternative diagnoses: PE, Pneumonia, Pneumothorax, Pump failure, Pulse (ACS or arrhythmia), Plug or aspiration. Precipitants of a true exacerbation are separate: infection, pollution and irritants, and non-adherence. PE is the highest-yield miss, roughly 1 in 6 of unexplained exacerbations.
NIV Before Intubation
BiPAP in hypercapnic respiratory failure with pH below 7.35 reduces intubation, mortality and length of stay, and it is one of the strongest evidence bases in respiratory medicine. Start it early rather than after a trial of failure, and reassess with a blood gas within an hour: a pH that is not improving is NIV failure and means intubation.
Bronchodilators Plus Steroids Are the Backbone
Short-acting beta agonist with an anticholinergic, and systemic corticosteroids.Prednisone 40 mg daily for 5 days is sufficient (REDUCE showed 5 days non-inferior to 14), and oral is as effective as IV. Longer courses add hyperglycemia, infection and bone loss without benefit.
Target Oxygen at 88 to 92%
Not higher.Excess oxygen causes hypercapnia through V/Q mismatch from released hypoxic vasoconstriction and the Haldane effect, not simply by removing hypoxic drive, and it increases mortality in prehospital COPD care. Titrate deliberately rather than leaving a non-rebreather running.
Antibiotics for the Right Patients
Give them for two or more of increased dyspnea, increased sputum volume, and increased sputum purulence, or for any patient requiring ventilatory support.Purulence is the single most useful of the three. Typical agents cover H. influenzae, S. pneumoniae and M. catarrhalis; add Pseudomonas cover for frequent exacerbations, prior isolation, bronchiectasis or recent broad-spectrum exposure.
Do Not Spirometer Them Acutely
Spirometry during an exacerbation is inaccurate and does not guide management. Do it at follow-up once recovered, which is also when the maintenance regimen should be reviewed. The same applies to labeling severity by FEV1 during the admission.
Do Not Run the Asthma Protocol
Steroid dose and duration, antibiotic use and oxygen targets all differ. Asthma gets higher steroid doses without routine antibiotics and a normal oxygen target; COPD gets 5 days of prednisone, selective antibiotics and 88 to 92%. Mixing them over-treats one and under-treats the other.
Optimize Before Discharge, Because Readmission Is the Rule
Confirm inhaler technique, review and step up maintenance therapy, vaccinate, refer to pulmonary rehabilitation, and address smoking.Arrange follow-up within 1 to 4 weeks.Exacerbations cluster and each one accelerates lung function decline, so the discharge is the intervention point for the next one. Assess for long-term oxygen only after recovery, not on the acute gas.
Constipation affects > 80% of ICU patients. Diarrhea is the #1 overnight cross-cover call. Prevent constipation from day 1, and always rule out C. diff before treating diarrhea.
💊 Constipation
Don't wait for the patient to complain. Start a bowel regimen on day 1 for ALL patients on opioids, immobilized, post-surgical, or on constipating medications (anticholinergics, calcium channel blockers, iron). A constipated inpatient becomes a distended, painful, ileus-complicated patient.
▶ Inpatient Bowel Escalation Protocol
DAY 1
Step 1, Prevention (ALL at-risk inpatients)
PEG 3350 (MiraLAX) 17g in 8 oz water PO daily Start on admission for: opioid use, immobility, post-surgical, anticholinergic meds, iron, CCBs. PEG = osmotic laxative, first-line per AGA-ACG 2023 (strong recommendation, moderate evidence). Safe in CKD. Do NOT use docusate (Colace), no better than placebo. Alternative:Lactulose (Kristalose) 15–30 mL PO daily if PEG unavailable or in hepatic encephalopathy patients (serves dual purpose). More bloating/gas than PEG.
↓ No BM × 48h ↓
DAY 2–3
Step 2, Add Stimulant
Senna (Senokot) 8.6–17.2 mg PO BID Add to PEG. Senna = stimulant laxative (activates colonic myenteric plexus). For opioid-induced constipation, start PEG + senna together from day 1. Can increase PEG to BID.
↓ No BM × 72h ↓
📋 CONSIDER KUB X-RAY AT THIS POINT
Order KUB when:
• No BM × 72h despite Steps 1–2
• Abdominal distension or new tympany on percussion
• Nausea/vomiting with absent bowel sounds
• Concern for ileus vs obstruction vs fecal impaction
• Post-operative patient with increasing abdominal girth What to look for: Stool burden (fecal loading pattern), air-fluid levels (obstruction), dilated loops (> 6 cm small bowel, > 9 cm cecum = concerning), free air (perforation). If obstruction suspected → CT abdomen/pelvis with contrast.
↓
DAY 3–4
Step 3, Add Second Stimulant / Increase Osmotic
Bisacodyl (Dulcolax) 10 mg PO daily or 10 mg PR Add to Steps 1–2. PR suppository works faster (15–60 min vs 6–12h PO). Avoid in bowel obstruction. Can also increase PEG to BID–TID. Or add Lactulose 15–30 mL PO q6–8h as additional osmotic agent alongside PEG. Particularly useful in patients with concomitant hepatic encephalopathy.
↓ Still no BM despite 72h escalation ↓
DAY 4–5
Step 4, Opioid-Specific Reversal
Methylnaltrexone (Relistor) 8–12 mg SC q48h OR Naloxegol (Movantik) 25 mg PO daily Peripheral μ-opioid antagonist, reverses opioid-induced constipation WITHOUT crossing BBB. No reversal of analgesia. Use when standard regimen fails.
↓ Impaction / acute obstipation ↓
RESCUE
Step 5, Acute Impaction / Last Resort
Soap suds enema (SSE) 1500 mL PR, first-line rectal intervention. Gentle, safe in CKD. Tap water enema, alternative if SSE unavailable. Safe in renal patients. Fleet enema (sodium phosphate) PR, faster acting but ⚠️ avoid in CKD (fatal hyperphosphatemia). Manual disimpaction if palpable fecal mass on DRE, last resort, requires analgesia/sedation. Order of preference: SSE → tap water → Fleet (if no CKD) → manual disimpaction.
▶ Bowel Agents -Full Table
Drug (Brand)
Class
Dose
Onset
Key Notes
Docusate (Colace) NOT RECOMMENDED
Stool softener
,
,
No better than placebo. Omitted from all AGA-ACG 2023 recommendations. Removed from hospital formularies (UAB 2024). No FDA-approved indication. Do not prescribe.
PEG 3350 (MiraLAX) 1ST LINE
Osmotic laxative
17g in 8 oz water PO daily–BID
24–48h
First-line per AGA-ACG 2023 (strong recommendation, moderate evidence). Non-absorbed. Less bloating than lactulose. Safe in CKD. Can increase to TID if refractory.
Senna (Senokot) 2ND LINE
Stimulant laxative
8.6–17.2 mg PO BID (1–2 tabs)
6–12h
Add to PEG. Stimulates colonic motility via myenteric plexus. In OIC, start PEG + senna together from day 1. Conditional recommendation per AGA-ACG 2023.
Bisacodyl (Dulcolax) ESCALATION
Stimulant laxative
10 mg PO daily or 10 mg PR
PO: 6–12h PR: 15–60 min
Add when PEG + senna insufficient. PR suppository much faster. Strong recommendation per AGA-ACG 2023. Avoid in acute abdomen or bowel obstruction.
Lactulose (Kristalose) ALTERNATIVE
Osmotic laxative
15–30 mL PO q6–8h
24–48h
Also used for hepatic encephalopathy (different dose: 30–45 mL q1–2h until BM). More bloating/gas than MiraLAX.
Methylnaltrexone (Relistor) OIC-SPECIFIC
Peripheral μ-opioid antagonist
8 mg SC (< 62 kg) or 12 mg SC (≥ 62 kg) q48h
30 min–4h
Targets opioid-induced constipation (OIC) specifically. Does NOT cross BBB -no reversal of analgesia or withdrawal. Expensive. Use after standard regimen fails.
Naloxegol (Movantik) OIC-SPECIFIC
Peripheral μ-opioid antagonist (PO)
25 mg PO daily (12.5 mg if CrCl < 60 or moderate CYP3A4 inhibitor)
6–12h
Oral alternative to methylnaltrexone. Avoid with strong CYP3A4 inhibitors. Renal dose needed.
Magnesium citrate ADJUNCT
Osmotic / saline laxative
150–300 mL PO × 1
30 min–3h
Fast-acting. Avoid in renal failure (hypermagnesemia). Single-use, not for maintenance.
Soap suds enema (SSE) RESCUE
Rectal enema
1500 mL warm water + castile soap PR
5–30 min
First-line rectal intervention. Safe in CKD. Stimulates peristalsis via distension + mild irritation. Preferred over Fleet in renal patients.
Tap water enema RESCUE
Rectal enema
500–1000 mL warm tap water PR
5–30 min
Alternative to SSE. Safe in CKD. Less effective than SSE but gentler. Can repeat.
Fleet enema (sodium phosphate) ACUTE ONLY
Rectal enema
1 bottle (133 mL) PR × 1
2–15 min
⚠️ Avoid in CKD, can cause fatal hyperphosphatemia. Avoid in elderly, dehydrated, or bowel obstruction. Use SSE or tap water enema instead.
▶ Special Situations
Scenario
Approach
Opioid-induced (most ICU patients)
PEG 3350 + senna from day 1 → escalate per protocol. Methylnaltrexone if refractory. Consider opioid rotation or reduction.
Post-operative ileus
Ambulation is the best treatment. Gum chewing stimulates gut motility. Alvimopan (Entereg) 12 mg PO BID × 7 days for post-surgical ileus (hospital use only). Avoid NG tube for uncomplicated ileus.
Hepatic encephalopathy
Lactulose 30–45 mL q1–2h titrated to 3–4 BMs/day. Goal is ammonia clearance, not just bowel movement. Rifaximin 550 mg PO BID for maintenance. See HE topic.
Hyperkalemia (kayexalate alternative)
Patiromer (Veltassa) or sodium zirconium (Lokelma) preferred over sodium polystyrene sulfonate (Kayexalate) -Kayexalate has risk of bowel necrosis and questionable efficacy.
CKD / dialysis patients
Avoid Fleet enemas (hyperphosphatemia), magnesium-containing laxatives (hypermagnesemia), and mineral oil (aspiration risk). Use PEG 3350 + senna (MiraLAX), lactulose, or bisacodyl. Lactulose is safe in CKD and can be used as PEG alternative.
C. difficile concern
If new diarrhea after bowel regimen → check C. diff toxin. Hold laxatives. If C. diff positive: fidaxomicin 200 mg PO BID × 10d (preferred) or vancomycin 125 mg PO QID × 10d. Avoid loperamide.
🚿 Diarrhea
Rule out C. difficile before giving antidiarrheals. Loperamide in active C. diff infection can precipitate toxic megacolon. Always send C. diff toxin PCR if new diarrhea in a patient on antibiotics, recent hospitalization, or age > 65.
▶ Inpatient Diarrhea -Workup & Management
STEP 1
Assess & Rule Out Dangerous Causes
Check immediately:
• C. diff toxin PCR, if on antibiotics, recent hospitalization, age > 65, immunosuppressed
• Stool studies, culture, ova & parasites if travel history or immunocompromised
• Rectal exam, rule out overflow diarrhea from fecal impaction (liquid stool around impacted mass, commonly missed!)
• KUB, if distension or concern for obstruction/toxic megacolon
• Electrolytes, check K, Mg, Na (diarrhea causes rapid depletion)
↓
STEP 2
Review Medications
Common offenders:
• Antibiotics, most common cause of inpatient diarrhea. Consider narrowing spectrum
• Lactulose / PEG overdose, check if bowel regimen needs dose reduction
• Magnesium-containing meds, antacids, supplements
• Metformin, colchicine, SSRIs, dose-dependent
• Enteral feeds, rate, osmolality, formula type (see tube feed section below)
• Sorbitol-containing elixirs, liquid acetaminophen, liquid potassium often contain sorbitol
↓
STEP 3
Treat by Cause
• C. diff positive: Fidaxomicin 200 mg PO BID × 10d (preferred) or vancomycin 125 mg PO QID × 10d. Stop offending antibiotic if possible. No loperamide.
• Antibiotic-associated (C. diff negative): Loperamide 4 mg × 1, then 2 mg after each loose stool (max 16 mg/day). Consider probiotics (Saccharomyces boulardii)
• Tube feed diarrhea: Reduce rate by 25%, switch to peptide-based or fiber-enriched formula, check for sorbitol in meds, add banana flakes or fiber supplement
• Overflow (impaction): Disimpact first, then restart bowel regimen. Do NOT give loperamide
• Medication-related: Dose-reduce or substitute the offending agent
• Secretory / high-output: Octreotide 50–100 mcg SC q8h for refractory secretory diarrhea (carcinoid, VIPoma, short gut, chemo-related)
▶ Antidiarrheal Agents -Full Table
Drug (Brand)
Class
Dose
Onset
Key Notes
Loperamide (Imodium) 1ST LINE
Peripheral μ-opioid agonist
4 mg × 1, then 2 mg after each loose stool
1–3h
Max 16 mg/day. ⚠️ CONTRAINDICATED in C. diff, bloody diarrhea, toxic megacolon, ileus. Does not cross BBB at standard doses. Safe in CKD. OTC.
Bismuth subsalicylate (Pepto-Bismol) ADJUNCT
Antisecretory / antimicrobial
524 mg (2 tabs) PO q30min–1h PRN
30–60 min
Max 8 doses/day. Avoid with aspirin allergy or anticoagulants (salicylate content). Turns stool/tongue black (harmless). Helpful for traveler's diarrhea.
Diphenoxylate-atropine (Lomotil) 2ND LINE
Opioid agonist + anticholinergic
5 mg/0.05 mg: 2 tabs QID, then taper
45–60 min
Schedule V controlled. Atropine added to discourage abuse. Same contraindications as loperamide. May cause anticholinergic effects at high doses.
Cholestyramine (Questran) BILE ACID
Bile acid sequestrant
4 g PO BID–TID (mix in water)
24–48h
First-line for bile acid diarrhea (post-cholecystectomy, ileal resection, Crohn's). Binds bile acids in gut. Must take 1h before or 4h after other meds (impairs absorption).
Octreotide (Sandostatin) REFRACTORY
Somatostatin analog
50–100 mcg SC q8h (can ↑ to 500 mcg)
30 min
For secretory / high-output diarrhea: carcinoid, VIPoma, short gut syndrome, chemo-induced, refractory to other agents. Also used for GI fistula output reduction. Expensive.
Psyllium (Metamucil) BULK FORMER
Soluble fiber
1 rounded tsp (3.4 g) in 8 oz water PO TID
12–72h
Absorbs water → bulks stool. Helpful for tube feed diarrhea and mild functional diarrhea. Must take with adequate water (risk of obstruction if dehydrated). Also used for IBS-D.
Probiotics (Saccharomyces boulardii) ADJUNCT
Live yeast probiotic
250–500 mg PO BID
Days
Best evidence for antibiotic-associated diarrhea prevention. Goldenberg, Cochrane 2017. Avoid in immunocompromised (risk of fungemia). Not effective for acute C. diff treatment.
Kaolin-pectin (Kaopectate) ADJUNCT
Adsorbent
60–120 mL PO after each loose stool
Variable
Mild effect. Adsorbs toxins and bacteria. Safe but less effective than loperamide. Can impair absorption of other medications.
▶ Tube Feed Diarrhea -ICU Specific
Cause
Intervention
Rate too high
Reduce rate by 25%. Advance slowly (10–20 mL/h q4–6h). Continuous feeds cause less diarrhea than bolus feeds.
Hyperosmolar formula
Switch to isotonic, peptide-based formula (e.g., Peptamen, Vital AF). Elemental formulas for severe malabsorption.
Sorbitol in medications
Switch liquid meds to tablet/crush form. Common culprits: liquid acetaminophen, KCl elixir, liquid theophylline. Each 5 mL of sorbitol-containing elixir adds osmotic load.
Fiber deficiency
Add soluble fiber supplement (banana flakes 2 tbsp q8h via tube, or switch to fiber-enriched formula like Jevity 1.2 or Promote with Fiber).
Contamination
Replace tubing q24h. Use closed-system ready-to-hang bags. Hang time ≤ 8h for open systems. Check for improper storage.
C. diff
Always rule out even in tube-fed patients. Do NOT stop feeds for C. diff, trophic feeding maintains gut mucosal integrity.
💎 Key Pearls
Constipation Pearls
Fleet enema + CKD = hyperphosphatemia.Can be fatal. Use tap water enema instead in any patient with renal impairment.
Docusate (Colace) is no better than placebo. The 2023 AGA-ACG Joint Guideline omitted docusate from all recommendations. McRorie 2021 reviewed 7 RCTs, none showed benefit over placebo. Multiple hospitals have removed it from formulary. Use PEG 3350 + senna instead.
Methylnaltrexone (Relistor) does NOT reverse analgesia. It's peripherally restricted -blocks opioid receptors in the gut only. No crossing the BBB. Safe to give without worrying about pain control.
"Nothing by mouth" doesn't mean nothing for the gut. Bisacodyl suppositories and enemas work even if the patient is NPO. Don't forget rectal options.
Diarrhea Pearls
Never give loperamide in C. diff or bloody diarrhea. Slowing gut motility traps toxins → toxic megacolon, perforation, death. Always rule out C. diff first.
Overflow diarrhea ≠ real diarrhea. Liquid stool leaking around a fecal impaction is the #1 missed diagnosis. Always do a rectal exam before treating "diarrhea" with antidiarrheals, you may need to disimpact instead.
Tube feed diarrhea is rarely infectious. Check for sorbitol in meds, reduce rate, add fiber, and switch to peptide-based formula before ordering stool studies.
Cholestyramine is the answer for post-cholecystectomy diarrhea. Bile acid malabsorption is the #1 cause. Must separate from other medications by 1h before or 4h after (it binds everything).
Quick Reference
Inotropes Guide
When the heart can't squeeze -agents that increase cardiac contractility. Know the hemodynamic profile of each before you hang the drip.
Inotropes ≠ vasopressors. Vasopressors increase SVR (squeeze vessels). Inotropes increase contractility (squeeze heart). Some agents do both. Picking the wrong one kills patients -a patient in cardiogenic shock who gets phenylephrine (pure vasoconstrictor, no inotropy) will get worse.
Milrinone (↓ PVR + inotropy) or dobutamine. Add inhaled epoprostenol/iNO for selective pulmonary vasodilation. Avoid volume loading -worsens RV dilation.
Post-cardiac surgery (low CO syndrome)
↓ CO post-CPB, stunned myocardium
Milrinone (preferred -↓ afterload helps stunned heart, ↓ PVR). Or dobutamine. Epinephrine if hemodynamically significant.
Bridge to LVAD / transplant
End-stage HFrEF failing oral meds, awaiting mechanical support
Milrinone (continuous infusion, can use outpatient via PICC). Or dobutamine.
ADHF -"warm and wet" needing diuresis
Low CO limiting diuretic response, adequate BP
Low-dose dobutamine (2–5 mcg/kg/min) to augment renal perfusion for diuresis. Short-term only.
Inotrope Comparison
Agent (Brand)
Mechanism
Dose
Hemodynamic Effect
Best For
Watch Out
Dobutamine (Dobutrex) 1ST LINE
β₁ > β₂ agonist
2–20 mcg/kg/min IV
↑ CO, ↑ HR, mild ↓ SVR (β₂ vasodilation). Net MAP may be unchanged or slightly ↓.
First-line inotrope in most cardiogenic shock (if MAP adequate). Septic shock with cardiac dysfunction. Augments diuresis in acute HF.
Never use alone if MAP < 65 -can drop BP via β₂ vasodilation. Always pair with NE if hypotensive. Tachycardia dose-limiting. Arrhythmogenic (↑ O₂ demand). Tachyphylaxis after 72h (downregulation of β-receptors).
Milrinone (Primacor) 1ST LINE
PDE3 inhibitor (↑ cAMP)
0.125–0.75 mcg/kg/min IV (skip loading dose in ICU -causes hypotension)
RV failure / pulmonary HTN (↓ PVR is key advantage). Post-cardiac surgery. Bridge to LVAD/transplant. Works when β-receptors are downregulated (chronic HF on BB) -bypasses β-receptor.
Hypotension (vasodilation) -more than dobutamine. Renally cleared -dose-adjust in AKI/CKD. Thrombocytopenia (rare). Longer half-life (2–3h) -effects persist after stopping. Do NOT give loading dose in ICU (severe hypotension).
Avoid. Inferior to NE in shock SOAP II, 2010. Only remaining role: symptomatic bradycardia if no pacing.
Twice the arrhythmia rate of NE (24.1% vs 12.4%). No overall mortality difference in SOAP II; higher mortality with dopamine only in the cardiogenic shock subgroup. "Renal-dose dopamine" is a myth -no renal protectionBellomo, 2000. Unpredictable dose-response. Avoid in ICU.
Levosimendan (Simdax) SPECIALIZED
Calcium sensitizer + K-ATP channel opener
0.05–0.2 mcg/kg/min IV × 24h
↑ CO, ↓ SVR, ↓ PVR. Inotropy without ↑ O₂ demand (unique). Active metabolite lasts 7–9 days.
Decompensated HF (Europe -not FDA-approved in US). Post-cardiac surgery. Bridge. Does not increase myocardial O₂ demand (unlike all other inotropes).
Not available in the US. Hypotension. Effect lasts days after stopping (long-acting metabolite). Limited data vs milrinone.
Is MAP < 65? → Start norepinephrine first (inopressor). You need MAP before you add a pure inotrope.
MAP adequate but CO is low? (cold extremities, poor cap refill, ↑ lactate, low ScvO₂) → Add dobutamine (first-line inotrope).
RV failure or pulmonary HTN? → Milrinone preferred (↓ PVR). Consider inhaled epoprostenol or iNO for selective pulmonary vasodilation.
Patient on chronic beta-blocker? → β-receptors are downregulated. Milrinone works better than dobutamine (PDE3 pathway bypasses β-receptor).
Need both inotropy + vasopressor? → Epinephrine (inopressor). Or NE + dobutamine as separate drips (more titratable).
Refractory to all above? → Mechanical circulatory support: IABP, Impella, ECMO. Call your interventional cardiology / cardiac surgery team early.
Key Pearls
All inotropes increase myocardial O₂ demand (except levosimendan). In ischemic cardiogenic shock, this is a double-edged sword -you're helping the pump but potentially worsening the ischemia. Keep doses as low as effective.
"Renal-dose dopamine" is a myth.Bellomo, 2000: no renal protection. SOAP II, 2010: double the arrhythmias (24.1% vs 12.4%) with no overall mortality difference (48.5% vs 52.5%, p = 0.10); the mortality signal was confined to the cardiogenic shock subgroup. There is no role for dopamine as an inotrope in modern ICU care.
Dobutamine tachyphylaxis occurs after ~72h due to β₁-receptor downregulation. If the patient stops responding, switch to milrinone (PDE3 pathway) or add mechanical support.
Milrinone has a 2–3h half-life. If the patient drops their BP on milrinone, the effect persists for hours after stopping -unlike dobutamine (t½ ~2 min). Plan accordingly. Also: renally cleared -dose-reduce in AKI.
Epinephrine falsely elevates lactate via β₂-mediated aerobic glycolysis. If you're running epi for inotropy, you cannot use lactate clearance to assess resuscitation adequacy. Use ScvO₂, echo, or CI instead.
Digoxin toxicity = "any arrhythmia." Classic: regularized afib, bigeminy, bidirectional VT. Hypokalemia potentiates it. Always check K⁺ with dig level. Reversal: DigiFab (digoxin-specific Fab fragments).
RoundsRx Infographic Series · #8 · Cardiovascular · PDF 139 KB
EmergentICU
Pulmonary Embolism
Clot in the pulmonary vasculature. Severity ranges from subclinical (Category A) to cardiopulmonary failure (Category E). The AHA/ACC 2026 guideline introduces a new A–E classification system, classify immediately to determine disposition and therapy.
🔍 Overview
Pathophysiology
PE kills via acute right ventricular failure, not hypoxemia. Clot lodges in pulmonary vasculature → acute ↑ PVR → RV pressure overload → RV dilation → interventricular septum bows into LV → ↓ LV preload → ↓ cardiac output → obstructive shock → PEA arrest. Understanding this mechanism drives every management decision: why you avoid fluids, why intubation is dangerous, why thrombolysis saves lives in Category E PE.
🚨 NEW 2026 PARADIGM: The AHA/ACC 2026 guideline replaces "massive / submassive / low-risk" with an integrative Category A–E system. This incorporates clinical severity scores, biomarkers, RV imaging, hemodynamics, and respiratory status, shifting focus from anatomical clot burden to pathophysiological impact. Patients may transition between categories with reassessment.
Category
Description
Criteria
Disposition
Treatment
A SUBCLINICAL Old: incidental (not previously classified)
Asymptomatic, incidental PE (found on CT for another reason)
No symptoms attributable to PE. Incidental finding (e.g., cancer staging CT).
ED discharge with DOAC
Anticoagulation. Segmental or larger → treat. Isolated subsegmental → shared decision-making (treat vs surveillance).
PESI III–V, sPESI ≥ 1, or Hestia ≥ 1. C1 = normal RV + normal biomarkers C2 = abnormal RV OR elevated biomarker C3 = abnormal RV AND elevated biomarker
Hospitalize. C3 → monitored bed (ICU/stepdown)
Anticoagulation. PERT* (Pulmonary Embolism Response Team) assessment for C2–C3 (Class 1). Close monitoring first 24–72h. Advanced therapy only if clinical deterioration.
D INCIPIENT FAILURE Old: Submassive PE (high-risk subset)
Anticoagulation + PERT (Class 1). CDT* (Catheter-Directed Thrombolysis) or mechanical thrombectomy may be considered (Class 2b). Systemic tPA if rapidly deteriorating.
E CARDIOPULMONARY FAILURE Old: Massive PE
Persistent hypotension / cardiac arrest
E1 = SBP < 90 for ≥ 15 min despite resuscitation, requiring vasopressors, or cardiac arrest
🔄 Old → New mapping: "Massive PE" ≈ Category E. "Submassive PE" ≈ Category C3–D (depending on hemodynamics). "Low-risk PE" ≈ Category A–B. The 2026 system adds granularity, C1 vs C2 vs C3 determines monitoring intensity, and D captures the "pre-arrest" patients who were previously lumped into submassive.
How to Categorize at the Bedside,4-Step Algorithm
Work top-down. Stop at the first category that fits. You need 4 pieces of data: (1) vitals & pressor status, (2) PESI/sPESI or Hestia score, (3) RV assessment (bedside echo or CT-PA RV:LV ratio ≥ 1.0), (4) biomarkers (troponin, BNP/NT-proBNP).
Step
Ask
If YES →
1
Hemodynamic collapse? Cardiac arrest, or SBP < 90 for ≥ 15 min despite fluids, requiring vasopressors.
E Activate PERT, prepare systemic tPA / thrombectomy / ECMO.
2
Incipient failure? Transient hypotension responding to fluids or single pressor (D1), OR normotensive shock: lactate ↑, AKI, oliguria, altered MS, rising O2 needs, worsening RV strain (D2).
D ICU, PERT consult, anticoag + consider CDT/thrombectomy (Class 2b).
3
Symptomatic with elevated severity? PESI III–V, sPESI ≥ 1, or Hestia ≥ 1, but hemodynamically stable. Then sub-classify using RV + biomarkers: • Both normal → C1 (ward) • One abnormal (RV OR biomarker) → C2 (monitored bed + PERT) • Both abnormal (RV AND biomarker) → C3 (ICU/stepdown + PERT)
C Hospitalize. Monitoring intensity matches the subcategory.
4
Symptomatic but low severity? sPESI = 0, PESI class I–II, Hestia 0, normal vitals, no RV strain, no biomarker elevation. B1 = subsegmental, B2 = non-subsegmental.
B DOAC, early discharge or directly from ED, 48–72h follow-up.
0
Asymptomatic incidental finding (e.g., PE seen on cancer staging CT, no PE-attributable symptoms).
A Outpatient DOAC if segmental or larger; shared decision-making if isolated subsegmental.
⚡ Bedside shortcut: Check vitals first (rules in/out D & E in 10 seconds). If stable, calculate sPESI: if 0, patient is B. If ≥ 1, get bedside echo + troponin + BNP to separate C1 / C2 / C3. The only categories requiring advanced imaging and biomarkers before categorization are C and its subtypes.
🔴 Re-categorize q6–12h in the first 24–72h. Patients transition. A C2 can decompensate to D or E. A D1 resolving with fluids may re-stratify to C3. Don't lock in the ED category: serial lactate, troponin trend, and RV reassessment drive escalation and de-escalation.
Risk Factors (Virchow's Triad), "SHE"
Mechanism
Examples
Stasis
Immobilization, post-op (especially ortho), long flights, paralysis, obesity, heart failure
Hypercoagulability
Cancer (especially pancreatic, lung, GI), OCPs/HRT, pregnancy/postpartum, Factor V Leiden, prothrombin mutation, antiphospholipid syndrome, nephrotic syndrome
Endothelial injury
Surgery, trauma, central venous catheters, prior DVT/PE, smoking
Presentation
Dyspnea -most common symptom (~80%), often acute onset
Pleuritic chest pain -sharp, worse with inspiration (~50%)
Tachycardia -often out of proportion to clinical picture
Hypoxia -but ~20% have normal SpO2 (A-a gradient usually elevated)
Syncope -suggests Category E PE (transient loss of CO). Present in ~10%. In patients hospitalized for first-episode syncope, ~17% had PE on systematic workup PESIT, 2016, consider PE workup in unexplained syncope with risk factors.
Hemoptysis (~7%), leg swelling (concurrent DVT in ~50%)
New-onset atrial fibrillation -RV dilation stretches the RA → Afib
Classic triad (dyspnea + pleuritic pain + hemoptysis) is present in < 20% of cases. PE is a great mimicker -always on your differential for unexplained tachycardia, new Afib, syncope, or hypoxia out of proportion. Post-op patients with sudden desaturation = PE until proven otherwise.
Wells Score for PE
Criterion
Points
Clinical signs/symptoms of DVT
3.0
PE is #1 diagnosis or equally likely
3.0
Heart rate > 100
1.5
Immobilization (≥ 3 days) or surgery in past 4 weeks
1.5
Previous DVT/PE
1.5
Hemoptysis
1.0
Active cancer (treatment within 6 months or palliative)
1.0
Score ≤ 4 (PE unlikely): Check D-dimer. If negative → PE ruled out. If positive → CTPA. Score > 4 (PE likely): Go directly to CTPA. Skip D-dimer (too many false positives).
Assess clinical suspicion. Is PE on the differential? If clinical gestalt is very low → apply PERC rule. If all 8 negative → stop. No further testing needed.
Step 2
Calculate Wells score. ≤ 4 (PE unlikely) → proceed to D-dimer. > 4 (PE likely) → skip D-dimer, go directly to CTPA.
Step 3
D-dimer (if Wells ≤ 4). Use age-adjusted cutoff for patients > 50: age × 10 ng/mL (e.g., 65-year-old → cutoff 650). Negative → PE ruled out. Positive → CTPA.
Step 4
CTPA -gold standard imaging. Sensitivity > 95%, specificity > 97%. Also provides RV/LV ratio for risk stratification. If PE confirmed → risk stratify into the 2026 Categories A to E.
Unstable
Patient too unstable for CT? Bedside echo → if RV strain + clinical picture → treat empirically with systemic tPA. Do not delay for imaging.
YEARS Algorithm (Simplified Approach)
Alternative to traditional Wells pathway. Check 3 items: (1) clinical signs of DVT, (2) hemoptysis, (3) PE is most likely diagnosis. If none present AND D-dimer < 1000 → PE excluded. If any present AND D-dimer < 500 → PE excluded. Otherwise → CTPA. Reduces unnecessary CT scans by ~14% YEARS, 2017.
Diagnostic Tests
Test
When
Key Points
CTPA
Gold standard -test of choice
Sensitivity > 95%. Shows clot location, RV/LV ratio (> 0.9 = RV dysfunction, which makes it Category C2 or higher), saddle PE. Avoid if contrast allergy or severe CKD → V/Q scan. Look for RV enlargement, septal bowing, reflux of contrast into IVC/hepatic veins.
D-dimer
Low/intermediate pretest (Wells ≤ 4)
High sensitivity (~95%), low specificity (~50%). Negative = rules out PE (NPV > 99%). Age-adjusted cutoff: age × 10 for > 50yo. Elevated in: cancer, pregnancy, post-op, DIC, infection -many false positives. Never order if high pretest probability.
V/Q Scan
Contrast allergy, severe CKD, pregnancy (controversial)
Reports as normal, low, intermediate, or high probability. Most useful if result is normal (rules out) or high probability (rules in). Intermediate = non-diagnostic → need CTPA or further workup. Best in patients with normal baseline CXR.
Bedside Echo
Unstable patient -cannot go to CT
Does NOT confirm PE but supports empiric treatment if: RV dilation (RVEDD > LVEDD), septal bowing (D-sign), McConnell's sign (RV free wall akinesis with apical sparing, ~95% specific), 60/60 sign (RVSP < 60 + PA acceleration time < 60 ms), TAPSE < 16 mm.
Troponin
All confirmed PE
Elevated = myocardial injury from RV strain. An abnormal biomarker makes it Category C2, and abnormal RV and biomarker makes it Category C3. Prognostic -higher mortality, increased risk of hemodynamic deterioration. Serial trending useful.
BNP / NT-proBNP
All confirmed PE
Elevated = RV pressure overload. BNP > 100 or NT-proBNP > 600 = higher risk. Combined with troponin for risk stratification.
Lower Extremity US
DVT suspected, or CTPA unavailable
Concurrent DVT found in ~50% of PE. Positive DVT + symptoms = treat for PE even without CTPA. Also useful in pregnancy to avoid radiation.
ECG
All suspected PE
Most common: sinus tachycardia. Classic findings (often absent): S1Q3T3, RBBB, RV strain pattern (T-wave inversions V1-V4), right axis deviation. New Afib in ~10%. Normal ECG does NOT rule out PE.
Imaging & Diagnostic Findings
Specific signs to look for on each modality. Most individual findings are insensitive (absent in many true PEs) but specific (strongly suggest PE when present). Use them to support diagnosis and risk stratification, not to rule PE out.
Modality
Key Findings
Clinical Significance
ECG
Sinus tachycardia (most common, ~40%). S1Q3T3 (deep S wave in lead I, Q wave in lead III, and T-wave inversion in lead III, reflects acute right-heart strain rotating the heart's electrical axis; classic but only ~20% of PEs). New RBBB, incomplete or complete (acute RV pressure overload slows right-sided conduction). TWI V1–V4 (RV strain pattern, repolarization abnormality across the right precordial leads). Right axis deviation. New atrial fibrillation (~10%, RV dilation stretches the right atrium). Low-voltage QRS or ST-depression in inferior leads.
None are sensitive or specific. Normal ECG does NOT rule out PE. Main value: rule out STEMI and pericarditis. S1Q3T3 + TWI V1–V4 together suggest larger clot burden / RV strain, associated with Categories C2–D.
Chest X-Ray
Normal CXR is the single most common finding (24–40%). Overall sensitivity ~33%, specificity ~59%, so CXR cannot rule PE in or out. Most common abnormal findings: linear/plate-like atelectasis (~70% of abnormal CXRs; splinting from pleuritic pain and surfactant dysfunction), small unilateral pleural effusion (30–50%, usually on the PE side), elevated hemidiaphragm (~20%, splinting on the PE side).
Westermark sign (focal oligemia, a wedge-shaped region of decreased pulmonary vascular markings distal to the clot, because the embolus blocks arterial flow and downstream vessels collapse). Sens ~14%, Spec ~92%.
Hampton's hump (wedge-shaped, pleural-based opacity with apex pointing toward the hilum, representing pulmonary infarction; late finding, > 12–24h after embolism, often near costophrenic angle). Sens ~22%, Spec ~82%. Infarction occurs in only ~10% of PEs because the lung has dual blood supply (pulmonary + bronchial); when it does, usually with concurrent CHF or shock impairing bronchial collateral.
Fleischner sign (enlarged central pulmonary artery, from acute pulmonary hypertension distending the PA, or a proximal clot directly bulging the vessel). Sens ~20%, Spec ~80%.
Palla sign (enlarged right descending pulmonary artery, specific to right-sided Category E PE).
Knuckle sign (abrupt tapering or "cut-off" of an occluded pulmonary artery branch on CXR).
Primary role: rule out mimics (pneumonia, pneumothorax, large effusion, pulmonary edema, widened mediastinum suggesting aortic dissection). Never exclude PE based on CXR, since 24–40% of confirmed PEs have a normal film. Essential baseline before V/Q scan, since V/Q is most reliable when the baseline CXR is clear; abnormal CXR pushes you to CTPA. Pearl: sudden hypoxia + tachycardia + a clear chest is a classic PE clue. When the CXR cannot explain the patient's oxygen requirement, PE moves up the differential.
Lower-Extremity Doppler Ultrasound
Non-compressible common femoral or popliteal vein = acute DVT (primary finding). Loss of respiratory phasicity in the vein. Absent color Doppler flow within the lumen. Directly visible intraluminal echogenic thrombus. Concurrent DVT found in ~50% of confirmed PE.
Positive DVT + PE-compatible symptoms = treat as PE even without CTPA (same anticoagulation). Especially useful in pregnancy (avoids fetal radiation), contrast allergy, severe CKD. Negative scan does NOT rule out PE, proximal calf-vein DVTs can still embolize.
Spiral CT (CTPA)
Intraluminal filling defect in pulmonary artery (dark clot surrounded by bright contrast within the vessel, the direct diagnostic sign). Saddle PE (large clot straddling the main PA bifurcation like a saddle over a horse's back, occludes both left and right pulmonary arteries). RV/LV ratio > 1.0 (measured on axial reconstructions, the RV is bigger than the LV, indicating acute pressure overload; prognostic for Category C2–C3). Septal bowing into LV (same mechanism as echo D-sign). Reflux of contrast into IVC / hepatic veins (contrast injected into an arm vein normally flows forward through the right heart, but with failing RV the tricuspid valve leaks and contrast washes backward down the IVC, sign of severe RV dysfunction). Pulmonary infarct (wedge-shaped peripheral opacity, same finding as Hampton's hump on CXR, seen earlier on CT). Enlarged main PA (> 29 mm, upstream dilation from proximal clot).
Gold standard. Sensitivity > 95%, specificity > 97%. Also drives risk stratification (RV/LV ratio separates C1 from C2–C3). Avoid if contrast allergy or severe CKD (CrCl < 30), use V/Q scan. Look explicitly at the RV in the report; don't just read "PE positive/negative."
V/Q Scan
Mismatched segmental perfusion defects (a lung segment ventilates normally on the radiolabeled gas scan but shows no perfusion on the radiolabeled-albumin scan, because the clot blocks blood flow while the airway is still open; this is the hallmark of PE). Reported by PIOPED criteria (from the Prospective Investigation of Pulmonary Embolism Diagnosis, 1990 landmark study, established the four-tier probabilistic reporting): normal, low, intermediate, or high probability.
Normal scan rules out PE (NPV > 95%). High-probability scan rules in PE (PPV ~85%). Intermediate / low probability = non-diagnostic in ~70% of cases, need CTPA or lower-extremity US. Preferred in pregnancy (lower breast radiation than CTPA by some protocols), contrast allergy, and severe CKD. Requires clear baseline CXR.
Echocardiography (Bedside / TTE)
Six bedside findings, in order of how often you'll see them:
RV dilation. RVEDD > LVEDD, or RV/LV ratio > 1 in the apical four-chamber view. What you're seeing: the normally smaller RV is now bigger than the LV. Why: acute clot burden raises RV afterload, the thin-walled RV dilates rather than hypertrophies acutely.
Septal flattening / D-sign. Best seen on parasternal short-axis. What you're seeing: the LV cavity, normally circular, is squashed into a "D" shape. Why: high RV pressure bows the interventricular septum leftward into the LV.
McConnell's sign. RV free-wall akinesis with preserved apical contraction. What you're seeing: the RV mid-wall barely moves but the RV apex still squeezes. Why: the apex is tethered to and tugged along by the still-contracting LV, masking the stunned RV mid-wall. ~95% specific for acute PE.
60/60 sign. Two cutoffs both under 60: RVSP < 60 mmHg AND pulmonary acceleration time < 60 ms. Why: reflects acute PA obstruction without the chronic adaptation of established pulmonary hypertension (in chronic PH the RV can generate much higher pressures). Distinguishes acute PE from chronic PH.
TAPSE < 16 mm. Tricuspid Annular Plane Systolic Excursion. What you're measuring: how far the tricuspid annulus descends toward the apex during systole, in M-mode. Why: the RV contracts mostly longitudinally; reduced annular descent is a quick proxy for RV systolic function. Lower TAPSE = worse RV.
Clot in transit (rare). Mobile thrombus directly visualized in RA, RV, or main PA. Why it matters: very high mortality, often triggers immediate systemic thrombolysis or surgical embolectomy without waiting for CTPA.
Does not definitively diagnose PE. In an unstable patient with compatible clinical picture, RV strain findings support empiric systemic thrombolysis without CTPA. Also central to risk stratification: RV dysfunction defines the transition from C1 to C2–C3. Serial echo tracks RV recovery after treatment.
Pulmonary Angiography
Direct catheter-based contrast injection into the pulmonary arteries. Intraluminal filling defect or abrupt vessel cutoff. Allows measurement of PA pressures.
Historical gold standard, replaced by CTPA for diagnosis (CTPA is non-invasive, faster, as accurate). Still clinically relevant as the access route during catheter-directed therapy (EKOS, FlowTriever, Penumbra Indigo), diagnostic angiography and intervention occur together. Invasive, risk of contrast load and catheter-induced arrhythmia. Rarely indicated for diagnosis alone.
Combining signs: No single finding diagnoses PE. Clinical gestalt + Wells / YEARS + D-dimer + CTPA is the diagnostic pathway. Imaging findings above are for pattern recognition on exam, read-outs, and risk stratification, not stand-alone rule-in or rule-out tools.
PE in Special Populations
Pregnancy
PE is a leading cause of maternal mortality. D-dimer is physiologically elevated in pregnancy -less useful. Start with lower extremity US → if positive DVT, treat without CTPA. If US negative → CTPA (preferred over V/Q in most guidelines -lower fetal radiation, more definitive). Anticoagulation: LMWH (enoxaparin) -DOACs are contraindicated in pregnancy. Continue through postpartum (minimum 3 months total, at least 6 weeks postpartum).
Cancer-Associated PE
LMWH was traditional standard. Now DOACs (edoxaban, rivaroxaban) are options for non-GI cancers Hokusai-VTE Cancer, 2018SELECT-D, 2018. Avoid DOACs in GI/GU cancers (higher mucosal bleeding risk). Duration: indefinite while cancer is active.
Renal Failure (CrCl < 30)
Use UFH (renally cleared, titratable, reversible). Avoid LMWH (accumulates → bleeding). Avoid DOACs if CrCl < 25-30. V/Q scan instead of CTPA if concerned about contrast nephropathy.
🚨 Management
Category E, Cardiopulmonary Failure (formerly "Massive PE")
This is a time-critical emergency. Do NOT wait for CTPA if echo shows RV strain + clinical picture fits. Mortality without treatment: 25–65%. Systemic thrombolysis is Class 1 per AHA/ACC 2026.
0–5 min
Recognize & stabilize. IV access × 2 large-bore. Supplemental O2 (high-flow NC or NRB). Avoid intubation if possible -positive pressure ventilation drops preload → hemodynamic collapse. If must intubate: ketamine induction (maintains hemodynamics), low tidal volume, lowest PEEP tolerated. Have vasopressors running BEFORE induction.
0–15 min
Hemodynamic support. Cautious IV fluids (250-500 mL max -RV is volume-sensitive, overloading worsens septal bowing into the LV [reverse Bernheim effect] and drops CO). Norepinephrine first-line pressor (supports MAP without increasing PVR). Consider vasopressin as adjunct. Avoid phenylephrine (pure alpha = increases PVR).
0–30 min
Systemic thrombolysis.Alteplase (tPA) 100 mg IV over 2 hours -standard protocol. In cardiac arrest: 50 mg IV bolus (push dose), may repeat × 1. Start heparin drip after tPA infusion (no bolus). Continue CPR for at least 60-90 min after tPA in arrest -it takes time to work. Jerjes-Sanchez, 1995
If tPA contraindicated
Catheter-directed therapy (CDT) or mechanical thrombectomy, Class 2a for Category E1 per AHA/ACC 2026. Options: catheter-directed lysis (low-dose tPA 12-24 mg over 12-24h directly into PA via EKOS), mechanical thrombectomy (FlowTriever, Penumbra Indigo), or hybrid. Surgical embolectomy if CDT unavailable and patient deteriorating.
Refractory
VA-ECMO as bridge to intervention or recovery in centers with capability. Consider if: cardiac arrest refractory to tPA, contraindication to lysis with ongoing hemodynamic collapse.
The gray zone. These patients are stable NOW but can decompensate rapidly. Close ICU/step-down monitoring is essential. PERT activation is Class 1 for Categories C–E per AHA/ACC 2026.
Immediate
Anticoagulation with heparin drip (UFH 80 units/kg bolus → 18 units/kg/hr, target aPTT 60-80). Heparin preferred initially because it's titratable and reversible if escalation needed. LMWH is recommended over UFH (Class 1) when parenteral therapy is needed and escalation is not anticipated AHA/ACC 2026. Use UFH if: high bleeding risk, considering thrombolysis, anticipating procedures, renal failure, or potential ECMO.
Risk assess
Check all prognostic markers: troponin (RV injury), BNP/NT-proBNP (RV strain), RV/LV ratio on CT (> 0.9), bedside echo (RV function, McConnell's sign, TAPSE). Calculate sPESI. Higher burden = closer monitoring.
Activate PERT
Pulmonary Embolism Response Team -multidisciplinary team (pulm, IR, CT surgery, heme, critical care). If available, activate early for Category C3 and above, where PERT activation is Class 1. They guide decisions about escalation to CDT or lysis.
Escalation triggers
Worsening tachycardia, rising troponin/BNP, new hypotension (SBP < 90), increasing O2 requirement, worsening RV on repeat echo → patient is transitioning from Category C to D. Escalate to catheter-directed therapy (Class 2b for D1–D2) or mechanical thrombectomy (Class 2b for D1–D2) per AHA/ACC 2026. Half-dose tPA (50 mg over 2h) remains an option MOPETT, 2013. HI-PEITHO, 2026 showed 61% reduction in decompensation with CDT in intermediate-high-risk PE.
PEITHO → HI-PEITHO evolution: PEITHO (2014) showed routine systemic tPA for submassive PE increased major bleeding (6.3%) and hemorrhagic stroke (2%) PEITHO, 2014. HI-PEITHO (2026) showed catheter-directed low-dose thrombolysis reduced decompensation by 61% in intermediate-high-risk PE (Category C3) without increased major bleedingHI-PEITHO, 2026. CDT is now the preferred escalation pathway over systemic tPA for Category C3–D patients. AHA/ACC 2026: mechanical thrombectomy is NOT recommended (Class 3: No Benefit) in low-risk PE (Categories A–C1).
DOACs are recommended over VKAs (Class 1) per AHA/ACC 2026: Apixaban 10 mg BID × 7 days → 5 mg BID or Rivaroxaban 15 mg BID × 21 days → 20 mg daily. No heparin bridging needed AMPLIFY, 2013EINSTEIN-PE, 2012. Apixaban preferred over rivaroxaban based on COBRRA, 2026 (54% less bleeding, equal efficacy).
If using warfarin: bridge with LMWH/UFH until INR 2-3 × 2 consecutive days. Monitor INR weekly then monthly.
Category A: Asymptomatic/incidental PE → can discharge from ED with DOAC.
Category B: Symptomatic low-severity → early discharge (24–48h or directly from ED) if sPESI = 0 AND Hestia criteria negative (see below).
Hestia Criteria -Outpatient PE Treatment
If ALL of the following are absent, patient may be safe for outpatient management:
sPESI = 0 + all Hestia criteria absent → candidate for discharge with DOAC and close follow-up (48-72h). Saves bed-days with no difference in outcomes HESTIA, 2011.
Catheter-Directed Therapy (CDT)
Modality
Mechanism
When to Consider
EKOS (EkoSonic)
Ultrasound-assisted catheter-directed lysis. Low-dose tPA (9–17 mg over 12–24h) delivered directly into PA with ultrasound waves to enhance clot penetration.
Category D–E (Class 2a for E1, Class 2b for D1–D2) per AHA/ACC 2026. Validated in HI-PEITHO, 2026 (61% reduction in decompensation, no increased bleeding) ULTIMA, 2014.
Class 2a for Category E1, Class 2b for D1–D2, Class 3 (No Benefit) for A–C1 per AHA/ACC 2026. Preferred over systemic tPA when bleeding risk is high FLARE, 2020.
Similar indications to FlowTriever. Lytic-free option. Same class recommendations per AHA/ACC 2026.
Surgical Embolectomy
Open cardiothoracic surgery to remove clot from PA.
Last resort. Category E when CDT unavailable and patient failing. Requires cardiothoracic surgery and cardiopulmonary bypass.
Anticoagulation Duration
Scenario
Duration
Notes
Provoked PE (major reversible risk factor: surgery, immobilization, trauma, OCPs)
3 months then stop
Transient risk factor removed. Low recurrence after stopping (~3%/year). AHA/ACC 2026: stopping at end of initial treatment phase is recommended when a major reversible risk factor is identified.
Unprovoked PE (no identifiable trigger) or persistent risk factors
≥ 3–6 months, then extend indefinitely
AHA/ACC 2026: extended anticoagulation beyond 3–6 months is recommended for first acute PE without a major reversible risk factor. Extended-dose DOAC (apixaban 2.5 mg BID or rivaroxaban 10 mg daily) reduces recurrence with lower bleeding AMPLIFY-EXT, 2013.
Recurrent VTE (2nd unprovoked event)
Indefinite
Lifelong anticoagulation. Use extended-dose DOAC for lower bleeding risk.
Cancer-associated PE
Indefinite (while cancer active)
LMWH historically preferred CLOT, 2003. DOACs (edoxaban, rivaroxaban, apixaban) now acceptable alternatives, but avoid DOACs in GI/GU cancers (higher mucosal bleeding) Hokusai-VTE Cancer, 2018.
PE with thrombophilia
Consider indefinite
Antiphospholipid syndrome = indefinite warfarin (avoid DOACs,TRAPS, 2018). Factor V Leiden homozygous = consider indefinite. Heterozygous = treat like unprovoked.
Always use retrievable filters -remove within 30-90 days once anticoagulation can be started. Permanent filters cause long-term complications (IVC thrombosis, filter migration, fracture).
IVC filter is NOT a substitute for anticoagulation. Start anticoag as soon as safe and retrieve the filter.
Evidence base: Adding an IVC filter to anticoagulation does NOT improve outcomes in patients who can be anticoagulated. PREPIC, 1998 showed a retrievable filter reduced early PE but doubled DVT recurrence, with no mortality benefit. PREPIC 2, 2015 confirmed no benefit in high-risk PE when anticoagulation is feasible. Reserve filters strictly for patients who genuinely cannot be anticoagulated.
tPA Contraindications
Absolute
Relative
Active internal bleeding (excluding menses)
Hemorrhagic stroke (any time)
Ischemic stroke within 3 months
Intracranial neoplasm, AVM, or aneurysm
Known bleeding diathesis
Significant head trauma or facial trauma within 3 months
Intracranial/spinal surgery within 3 months
Suspected aortic dissection
Recent surgery/procedure within 10 days
Recent internal bleeding (2-4 weeks)
Uncontrolled HTN (SBP > 180)
Current anticoagulation (INR > 1.7)
Pregnancy
Active peptic ulcer disease
CPR > 10 min (relative, not absolute)
Diabetic retinopathy
In cardiac arrest from Category E PE, relative contraindications may be overridden. The risk of death from PE outweighs the bleeding risk. Discuss with your attending.
📋 Case 1, Category C3 PE (Post-Surgical)
Patient: 45M, post-op day 3 from knee surgery, sudden-onset dyspnea, HR 110, SpO2 92%, BP 128/82.
Pre-test probability:Wells score = 4.5 (HR > 100 = 1.5, immobilization/surgery = 1.5, PE most likely dx = 1.5) → PE likely → CTPA directly (skip D-dimer).
CT-PA: Saddle PE with RV dilation, RV/LV ratio 1.2.
Risk stratification:
Hemodynamically stable (BP > 90) → NOT massive
RV dilation on CT + troponin 0.08 (elevated) + BNP 450 → Category C3 PE
sPESI score: age > 45 (+1), HR > 110 (+1) = 2 → high risk for decompensation
Patient: 62F with metastatic ovarian cancer, found unresponsive. PEA arrest. No pulse. CPR initiated.
Bedside echo during CPR: Severely dilated RV, septal bowing into LV, no pericardial effusion.
Clinical reasoning: PEA arrest + cancer + massively dilated RV → Category E PE until proven otherwise.
Treatment:
Push-dose tPA: Alteplase 50 mg IV bolus during CPR. Continue CPR for 60–90 min (tPA needs time).
Second bolus: If no ROSC after 15 min → repeat alteplase 50 mg IV.
ROSC achieved: Start heparin drip (no bolus after tPA). ICU admission. Post-ROSC care.
Imaging: CTPA once stable confirms bilateral PE with large clot burden.
Long-term: Cancer-associated PE → indefinite anticoagulation with LMWH (GU cancer, avoid DOACs).
Key lesson: In cardiac arrest with suspected PE, do NOT wait for imaging. Empiric tPA saves lives. Relative contraindications are overridden when the patient is coding.
📋 Case 3, Low-Risk PE Sent Home
Patient: 28F on OCPs, presents with 2 days of pleuritic chest pain and mild dyspnea. HR 88, BP 124/76, SpO2 98%.
Wells score: 4.5 (HR < 100 = 0, PE most likely dx = 3, OCPs = 1.5) → PE likely → CTPA.
CT-PA: Subsegmental PE in right lower lobe. RV/LV ratio 0.7 (normal). No RV strain.
Risk stratification:
Hemodynamically stable, no RV dysfunction, troponin negative, BNP normal → Low-risk PE
sPESI = 0 (age < 80, no cancer, no cardiopulm disease, HR < 110, SBP > 100, SpO2 > 90%)
Rivaroxaban 15 mg BID × 21 days → 20 mg daily. No heparin bridge needed.
Stop OCPs. Discuss alternative contraception.
Follow-up: PCP in 48–72 hours. Repeat imaging NOT routinely needed.
Duration: 3 months (provoked, OCP-related). No thrombophilia workup unless recurrent.
Key lesson: Not every PE needs admission. Low-risk PE with sPESI = 0 and Hestia-negative can go home safely on a DOAC.
📋 Case 4, PE in Pregnancy
Patient: 31F, 28 weeks pregnant, acute dyspnea and tachycardia (HR 115). SpO2 94%. Left leg swelling for 3 days.
D-dimer: Elevated, but D-dimer is physiologically elevated in pregnancy → not reliable.
Diagnostic approach:
Step 1: Lower extremity compression US → positive for left popliteal DVT.
Step 2: DVT confirmed + symptoms → treat for PE without CTPA (avoid radiation if DVT already found).
Treatment:
Enoxaparin 1 mg/kg BID (weight-based, use pre-pregnancy or actual weight). DOACs are contraindicated in pregnancy.
Monitor anti-Xa levels (target 0.6–1.0 at peak, 4h post-dose). Dose adjustments needed as pregnancy progresses.
Delivery plan: Switch to UFH at 36 weeks (shorter half-life, reversible with protamine). Hold LMWH 24h before planned delivery.
Postpartum: Resume LMWH → transition to DOAC or warfarin after delivery. Continue for minimum 3 months total AND at least 6 weeks postpartum.
Key lesson: In pregnancy, start with leg US, if DVT is found, treat without CT. LMWH is the anticoagulant of choice. Plan the delivery switch to UFH early.
📋 Case 5, Incidental PE Found on Staging CT
Patient: 58M with newly diagnosed lung adenocarcinoma. Staging CT chest/abdomen/pelvis incidentally finds a segmental PE in the right pulmonary artery. Asymptomatic. HR 78, BP 132/80, SpO2 97%.
Clinical question: Does an incidental PE need treatment?
Answer: Yes.
Incidental PE in cancer patients carries same mortality and recurrence risk as symptomatic PE.
ISTH and ASCO guidelines: Treat incidental PE the same as symptomatic PE.
Exception: isolated subsegmental PE, discuss with hematology, may consider surveillance.
Treatment:
LMWH or DOAC (this is lung cancer, not GI, DOACs are acceptable).
Apixaban 10 mg BID × 7 days → 5 mg BID.
Duration: Indefinite while cancer is active. Reassess if cancer enters remission.
Check for RV strain: Echo + troponin + BNP to rule out RV strain (Category C2 to C3) despite being asymptomatic.
Key lesson: Incidental PE in cancer patients is NOT benign. Treat it. Always check RV function even in asymptomatic patients.
📋 Case 6, Recurrent PE While on Anticoagulation
Patient: 54M with unprovoked PE 4 months ago, currently on apixaban 5 mg BID. Presents with new pleuritic chest pain and dyspnea. HR 105, SpO2 93%.
CTPA: New segmental PE in left lower lobe. RV/LV ratio 0.8. Old clot in right PA partially resolved.
Key questions:
Is the patient actually taking the medication? Check adherence, missed doses are the #1 cause of "failure."
Is there an occult malignancy? Unprovoked recurrent VTE has up to 10% cancer detection rate within 1 year.
Workup:
Age-appropriate cancer screening (CT chest/abdomen/pelvis, CBC, CMP, LDH, UA)
Consider anti-Xa level to confirm adequate drug levels
Treatment:
Switch to LMWH (enoxaparin 1 mg/kg BID), more reliable in cancer/malabsorption.
Consider IVC filter if recurrent PE despite therapeutic anticoagulation.
Lifelong anticoagulation, second unprovoked event = indefinite treatment.
Key lesson: Recurrent PE on a DOAC, check adherence first, then hunt for cancer and antiphospholipid syndrome. Switch drug class and plan for lifelong anticoagulation.
📋 Case 7, The PE That Wasn't (Aortic Dissection)
Patient: 67M with HTN, acute tearing chest pain radiating to back. Diaphoretic. HR 108, BP 185/110 right arm, 142/88 left arm. SpO2 95%.
Initial concern: Tachycardia + chest pain + dyspnea → PE was on the differential.
Red flags that point AWAY from PE:
Tearing/ripping quality radiating to back, classic dissection.
> 20 mmHg BP differential between arms, highly specific for type A dissection.
Severe hypertension, PE typically causes hypotension, not hypertension.
No VTE risk factors, no immobilization, surgery, or cancer history.
CTA chest: Stanford Type B aortic dissection. No PE.
Why this matters:
If you gave heparin for presumed PE → catastrophic bleeding into false lumen.
Always consider the differential before anticoagulating. PE, dissection, STEMI, and tamponade can all present with chest pain + tachycardia.
Key lesson: Not every tachycardic chest pain is PE. Check BP in both arms. Tearing pain to back + BP differential = dissection until proven otherwise. Anticoagulating a dissection can be fatal.
📋 Case 8, Saddle PE with Thrombus-in-Transit
Patient: 48F, 1 week post-cesarean section, sudden collapse. HR 130, BP 78/50, SpO2 82% on NRB. Altered mental status.
Bedside echo: Massively dilated RV. Mobile thrombus seen in the right atrium straddling the tricuspid valve (thrombus-in-transit). McConnell's sign positive.
This is a surgical emergency:
Thrombus-in-transit = clot trapped between venous system and pulmonary arteries. Mortality > 40% without intervention.
Risk of complete PA occlusion if thrombus embolizes further.
Treatment:
Systemic tPA 100 mg over 2 hours, despite being 1 week post-cesarean (relative contraindication overridden by life-threatening PE).
Norepinephrine for hemodynamic support. Avoid aggressive fluids.
If tPA fails or contraindicated: Emergent surgical embolectomy or catheter-directed therapy.
VA-ECMO as bridge if available and patient continues to deteriorate.
Post-stabilization: Heparin drip → transition to LMWH (postpartum, can use DOAC if not breastfeeding).
Key lesson: Thrombus-in-transit on echo is a surgical emergency. Don't wait for CT. Lyse immediately or call CT surgery. Post-surgical status is a relative, not absolute, contraindication when the patient is dying.
Monitoring by Category (2026 AHA/ACC)
Monitoring intensity tracks the A–E category. Re-categorize q6–12h in the first 24–72h, patients transition. Column headers below refer to the 2026 categories (old "massive" ≈ E, "submassive" ≈ C3–D, "low-risk" ≈ A–B).
Parameter
D – E (ICU)
C1 – C3 (Ward / Monitored bed)
A – B (Home / ED discharge)
Vitals
Continuous telemetry + q1–2h. Arterial line if on pressors.
Continuous telemetry + q2–4h. (C1 may step down to q4h once stable.)
q8h inpatient; home pulse ox optional after discharge.
Activate PERT / escalate care if any of the following develop:
SBP drops < 90 mmHg or new vasopressor requirement
Rising troponin or BNP despite anticoagulation
Worsening RV function on repeat echo
Increasing O2 requirement or new intubation need
New arrhythmia (Afib, VT)
Altered mental status (low CO to brain)
Transition to Oral Anticoagulation
When stable × 24-48h (vitals normalized, O2 weaned, troponin trending down): transition from heparin drip to oral DOAC.
Apixaban: Stop heparin → start apixaban 10 mg BID × 7 days → 5 mg BID. No overlap needed.
Rivaroxaban: Stop heparin → start rivaroxaban 15 mg BID × 21 days → 20 mg daily. No overlap needed.
Edoxaban: Requires 5-10 days of parenteral anticoag first → then edoxaban 60 mg daily.
Warfarin: Start warfarin while on heparin. Continue heparin until INR 2-3 × 2 consecutive days (typically 5-7 days overlap).
Follow-Up After Discharge,2026 AHA/ACC Structured Framework
AHA/ACC 2026 mandates structured post-PE follow-up, this is now a formal guideline recommendation, not just good practice.
Within 1 week of discharge: Communication or clinic evaluation to assess symptoms, bleeding, medication adherence, and early complications AHA/ACC 2026.
At or before 3 months: Clinical visit to determine anticoagulation duration (stop vs extend). Reassess risk factors, provoked vs unprovoked status, bleeding risk. This is the key decision point AHA/ACC 2026.
CTEPH screening at every visit for ≥ 1 year: If persistent dyspnea → echo → V/Q scan if elevated RVSP. CTEPH develops in 2–4% of PE survivors.
Thrombophilia workup: Consider if unprovoked PE in patient < 50 (Factor V Leiden, prothrombin mutation, antiphospholipid antibodies). Test AFTER completing anticoagulation (DOACs and warfarin affect results).
Cancer screening: If unprovoked PE in patient > 50 → age-appropriate cancer screening (colonoscopy, mammogram, CT chest, PSA if male).
📋 On Rounds
Pimp Questions
Why does PE cause RV failure? Walk me through the pathophysiology.
Clot in PA → acute ↑ pulmonary vascular resistance (PVR) → RV pressure overload → RV dilation → interventricular septum bows into LV (D-sign) → ↓ LV preload → ↓ cardiac output → obstructive shock. Simultaneously, RV wall tension increases → RV myocardial O2 demand rises while coronary perfusion falls → RV ischemia. Death is from acute cor pulmonale and cardiogenic shock, not hypoxemia.
What are the 8 PERC criteria and when do you apply them?
PERC (Pulmonary Embolism Rule-out Criteria): Apply ONLY when clinical gestalt is LOW (< 15% pretest). All 8 must be negative: (1) Age < 50, (2) HR < 100, (3) SpO2 ≥ 95%, (4) No hemoptysis, (5) No estrogen use, (6) No prior DVT/PE, (7) No unilateral leg swelling, (8) No recent surgery/trauma requiring hospitalization in past 4 weeks. All negative → PE ruled out without D-dimer. If ANY positive → proceed with Wells + D-dimer pathway.
What are the components of the Wells score for PE?
7 criteria: Clinical DVT signs (3.0), PE is #1 or equally likely diagnosis (3.0), HR > 100 (1.5), immobilization ≥ 3 days or surgery within 4 weeks (1.5), prior DVT/PE (1.5), hemoptysis (1.0), active cancer (1.0). ≤ 4 = PE unlikely → D-dimer.> 4 = PE likely → CTPA directly. The "PE most likely" criterion is subjective -this is the main limitation of Wells vs Geneva.
What is subsegmental PE and do you treat it?
Subsegmental PE: clot in subsegmental arteries (small, distal). Increasingly detected with better CT resolution. If no DVT on LE US and low risk for recurrence → may not need anticoagulation. Shared decision-making with the patient. If DVT present, prior VTE, cancer, or inpatient/immobilized → treat with standard anticoagulation. This is a gray zone -discuss with hematology or your attending.
How do you manage PE in pregnancy?
PE is a leading cause of maternal mortality. Workup: D-dimer unreliable (physiologically elevated). Start with LE US → if positive DVT, treat without CTPA. If negative → CTPA (preferred for definitive diagnosis). Treatment: LMWH (enoxaparin 1 mg/kg q12h) -DOACs are contraindicated (cross placenta). Continue through pregnancy + at least 6 weeks postpartum (minimum 3 months total). Hold LMWH 24h before planned delivery.
What is CTEPH and when should you suspect it?
CTEPH (Chronic Thromboembolic Pulmonary Hypertension): Occurs in ~4% of PE survivors. Organized thrombus persists → chronic PVR elevation → progressive RV failure. Suspect if: persistent dyspnea/exercise intolerance 3-6 months after PE despite anticoagulation. Screen with echo (elevated RVSP). Confirm with V/Q scan (more sensitive than CTPA for chronic disease). Treatment: pulmonary endarterectomy (PEA) is potentially curative.
📣 Sample Presentation
One-Liner
"Ms. Park is a 42-year-old on OCPs presenting with acute pleuritic chest pain and dyspnea × 1 day. HR 112, SpO2 93%. Wells score 7.5 (high). CTPA shows bilateral segmental PE with RV/LV ratio 1.2. Troponin 0.08. Classified as Category C3 PE."
Key Points to Cover on Rounds
Category C3 PE, formerly submassive (hemodynamically stable but RV strain). RV/LV ratio 1.2 on CTPA. Troponin mildly elevated 0.08, BNP 380. sPESI score 1. Anticoagulation: heparin drip started, aPTT 72 (therapeutic). Plan to transition to apixaban 10 mg BID × 7 days then 5 mg BID once stable. OCPs stopped. LE US: DVT left popliteal vein. Monitoring: serial troponin q6h (trending down 0.08 → 0.05), repeat echo tomorrow. Escalation plan: if SBP drops < 90 or worsening RV → PERT activation for CDT. Duration: 3 months (provoked by OCP + immobility).
Daily Rounds Checklist
Anticoagulation therapeutic? → aPTT in range (60-80) if on heparin drip. Anti-Xa if using LMWH. Confirm DOAC dosing correct.
Hemodynamics stable? → HR trending down? BP stable? O2 requirement decreasing? Any signs of deterioration?
RV function reassessment? → Repeat echo in 24-48h for Category C3 to D. TAPSE, RV/LV ratio improving?
Bleeding assessment? → Any signs of bleeding (GI, gums, hematuria, bruising)? Hgb stable?
DVT prophylaxis bilateral? → Concurrent DVT? Lower extremity US result? SCDs on non-affected leg.
Transition plan? → When to switch from heparin to oral DOAC? Which DOAC? Duration decision documented?
IVC filter needed? → Only if anticoag contraindicated. If placed, document retrieval plan (30-90 days).
Etiology workup? → Provoked vs unprovoked? If unprovoked and < 50yo: consider thrombophilia workup (after acute treatment). If > 50 + unprovoked: age-appropriate cancer screening.
Disposition planning? → If low-risk (sPESI 0, Hestia negative): outpatient with 48-72h follow-up. Category C3 to D: when safe to step down from ICU?
No bridging. Must take with food (bioavailability drops 40% without). Caution if CrCl < 30. EINSTEIN-PE, 2012
Heparin (UFH) CATEGORY C3 TO E
80 units/kg bolus → 18 units/kg/hr drip
aPTT q6h until therapeutic (60-80 sec), then q12-24h.
Protamine sulfate (1 mg per 100 units heparin given in past 2-3h).
Short half-life (60-90 min). Use when intervention likely or high bleed risk. Reversible. Monitor for HIT (platelet count q2-3 days).
Enoxaparin (Lovenox) BRIDGE / PREGNANCY
1 mg/kg SC q12h Or 1.5 mg/kg SC daily
Anti-Xa level (target 0.6-1.0 for q12h dosing). Check in obesity, renal impairment, pregnancy.
Protamine (partial reversal only ~60%).
Bridge to warfarin or primary therapy in pregnancy. Avoid if CrCl < 30 → use UFH. Weight-based, no cap needed in obesity (check anti-Xa).
Edoxaban (Savaysa)
60 mg daily (after 5-10 days of parenteral anticoag)
No routine monitoring.
PCC. No specific reversal agent.
Requires heparin/LMWH lead-in (unlike apixaban/rivaroxaban). Avoid if CrCl > 95 (paradoxically less effective). Good option for cancer-associated PE (non-GI) Hokusai-VTE Cancer, 2018.
Dabigatran (Pradaxa)
150 mg BID (after 5-10 days of parenteral anticoag)
No routine monitoring. Renal function q6–12mo.
Idarucizumab (Praxbind) 5 g IV, specific monoclonal reversal.
Direct thrombin inhibitor. Requires heparin/LMWH lead-in. Avoid if CrCl < 30. GI upset common. Noninferior to warfarin for VTE RE-COVER, 2009.
Warfarin (Coumadin)
Start 5 mg daily, adjust to INR 2-3
INR daily until stable, then weekly, then monthly. Target 2.0-3.0.
Vitamin K (oral/IV) + 4-factor PCC (KCentra) for life-threatening bleed. FFP if PCC unavailable.
Requires 5-7 day heparin/LMWH bridge. INR 2-3 × 2 consecutive days before stopping bridge. Many drug/food interactions. Last-line behind DOACs except in APS.
Thrombolytics
Drug
Dose
Route
Notes
Alteplase (tPA, Activase) CATEGORY E PE
100 mg IV over 2 hours Cardiac arrest: 50 mg IV bolus
Systemic IV
Standard of care for Category E PE. Major bleeding ~10%, ICH ~2%. Start heparin drip after infusion (no bolus). Continue CPR 60-90 min post-tPA if in arrest.
Alteplase (low-dose, CDT)
12-24 mg over 12-24 hours via catheter directly into PA
Catheter-directed (EKOS)
Used with ultrasound-assisted catheter. Significantly lower systemic bleeding than full-dose IV. Requires IR/interventional cardiology ULTIMA, 2014.
Half-dose tPA
50 mg IV over 2 hours
Systemic IV
For Category C3 to D with deterioration. Lower bleeding risk than full dose. Improved pulmonary artery pressures in MOPETT trial MOPETT, 2013. Not universally accepted -discuss with attending.
Tenecteplase
Weight-based single bolus
Systemic IV
Single-bolus administration (easier than 2h alteplase infusion). Studied in PEITHO for submassive PE -reduced decompensation but increased bleeding/stroke. Not first-line for Category C3.
V1-mediated vasoconstriction. Does not increase PVR. NE-sparing.
-
Dobutamine
2-20 mcg/kg/min
If evidence of RV failure with low CO. Adds inotropy to support RV contractility.
Can worsen hypotension (beta-2 vasodilation). Only use with concurrent vasopressor.
Phenylephrine AVOID
-
-
Avoid in PE. Pure alpha agonist → increases PVR → worsens RV afterload → further RV failure.
Key principle: In PE-related shock, the RV is failing against high PVR. You want to: (1) support SVR (norepinephrine), (2) avoid increasing PVR further (no phenylephrine), (3) consider RV inotropy if CO is low (dobutamine). Fluids are usually harmful -limit to 250-500 mL.
⚡ Summary
Summary
Classify Immediately Using the 2026 A to E Categories
The AHA/ACC 2026 guideline replaces massive/submassive with clinical categories A through E, running from subclinical disease to cardiopulmonary failure. Category assignment drives disposition and therapy, so it is done at the bedside on arrival rather than after the imaging is formally reported.
Diagnose With Pretest Probability, Not D-Dimer Alone
Wells or Geneva first.D-dimer rules out only in low or intermediate probability, and is raised by age, pregnancy, cancer, infection, surgery and inflammation. Use age-adjusted D-dimer above 50, and the YEARS algorithm, which applies a higher D-dimer threshold when none of its three items is present and safely reduces imaging.
Know When PERC Applies
Only in a patient already low risk by clinical gestalt, and all eight criteria must be negative.Applying PERC to a moderate or high probability patient is misuse and misses PE. Equally, a high-probability patient goes straight to imaging without a D-dimer.
CTPA Is the Test, With Alternatives
CT pulmonary angiography for most patients.V/Q scan when contrast is contraindicated, in renal failure and in pregnancy, where it delivers less breast radiation. Bedside echocardiography in an unstable patient: right ventricular dilation and strain support the diagnosis fast enough to act on when the patient cannot go to the scanner.
Category E Is the One That Needs Immediate Reperfusion
Cardiopulmonary failure, formerly massive PE: sustained hypotension or shock.Systemic thrombolysis, or catheter-directed therapy or surgical embolectomy where lysis is contraindicated.Give fluids cautiously: an overloaded right ventricle worsens with volume, so use norepinephrine early and consider inhaled pulmonary vasodilators.
Intermediate Risk Is Watched, Not Lysed by Default
Right ventricular strain on echo or CT with a positive troponin, but normotensive.PEITHO showed thrombolysis reduced hemodynamic decompensation but caused excess major bleeding and intracranial hemorrhage, so anticoagulate and monitor closely, reserving reperfusion for deterioration. Catheter-directed therapy is increasingly used here to get some of the benefit at lower bleeding cost.
Send the Low-Risk Patient Home
Use sPESI or the Hestia criteria to identify patients who can be treated as outpatients.Outpatient management of genuinely low-risk PE is safe and avoids an admission, provided the patient has support, can obtain the anticoagulant and has follow-up arranged. Confirm affordability before discharge, since an unfilled prescription is the commonest failure point.
Set the Duration by Provocation
Provoked by a major transient factor: 3 months.Unprovoked: at least 3 months then consider extended therapy, often with reduced-dose apixaban or rivaroxaban.Active cancer: continue while the cancer is active.Follow up for persistent dyspnea at 3 to 6 months, because chronic thromboembolic pulmonary hypertension is potentially curable by endarterectomy and is missed if nobody asks.
RoundsRx Infographic Series · #40 · Respiratory · PDF 155 KB
Text version
Pulmonology / Hematology · One Pager
Pulmonary Embolism
PE kills via RV failure, not hypoxia. PERC → Wells → D-dimer → CTPA. Category E = tPA. Category C3 to D = heparin + watch for deterioration. Low-risk = outpatient DOAC.
🧪 Diagnostic Algorithm
Low gestalt → PERC (all 8 negative → stop). Wells ≤ 4 → D-dimer (age-adjusted: age × 10 if > 50). Wells > 4 → CTPA directly. Unstable → bedside echo → treat empirically. V/Q if contrast allergy/CKD.
🚨 Treatment by Severity
Massive (SBP < 90): tPA 100 mg/2h. Norepi. Cautious fluids (250-500 mL). Avoid intubation. CDT if tPA contraindicated. Category C3 to D (stable + RV strain): heparin drip. PERT. Serial troponin. Escalate if deteriorating. Low-risk (sPESI 0 + Hestia negative): outpatient DOAC.
K⁺ > 5.5 mEq/L. ECG changes dictate urgency, not the number. Calcium stabilizes the membrane. Insulin + glucose shifts K⁺ intracellularly. Kayexalate and patiromer remove K⁺. Dialysis for refractory cases.
🔍 Overview
ECG Progression
Get an ECG before anything else. ECG changes = emergent regardless of the number. A patient with K⁺ 6.0 and peaked T's is sicker than a patient with K⁺ 7.0 and a normal ECG.
K⁺ Level
ECG Finding
Urgency
5.5–6.0
Peaked T waves (tall, narrow, symmetric -earliest sign)
Pseudohyperkalemia -hemolyzed sample (most common lab artifact), high WBC/plt count, tourniquet too tight
Rule out pseudohyperkalemia first: if the patient has no ECG changes, no risk factors, and the K⁺ is unexpectedly elevated → recheck on a non-hemolyzed, free-flowing sample before treating.
Pseudohyperkalemia -Deep Dive
Pseudohyperkalemia is a falsely elevated serum K⁺ due to K⁺ release from cells during or after blood collection -not a true reflection of in vivo potassium levels. Recognizing it prevents unnecessary (and potentially dangerous) treatment of a lab artifact.
Mechanisms
Hemolysis during phlebotomy -the most common cause. Traumatic draw, small-gauge needle, vigorous shaking of the tube, or pneumatic tube transport causes RBC lysis and K⁺ release. The lab usually flags the specimen as hemolyzed (hemolysis index elevated).
Prolonged tourniquet time -fist clenching with a tight tourniquet causes local ischemia and K⁺ leakage from forearm muscles. Can raise K⁺ by 0.5–1.5 mEq/L.
Thrombocytosis (plt > 500K) -during clot formation in a serum (red-top) tube, platelets degranulate and release intracellular K⁺. The higher the platelet count, the greater the artifact. A plasma (green-top/heparin) sample bypasses clotting and gives the true K⁺.
Leukocytosis (WBC > 70–100K) -seen in leukemia/lymphoma. Fragile WBCs lyse in vitro, releasing K⁺. Again, a plasma sample is more accurate.
In vitro hemolysis from specimen handling -delayed processing, refrigeration of whole blood, or prolonged storage allows ongoing K⁺ leak from cells.
Familial pseudohyperkalemia -rare inherited RBC membrane defect causing K⁺ leak at room temperature but not at 37°C.
How to Differentiate: Real vs. Pseudo
Feature
Pseudohyperkalemia
True Hyperkalemia
ECG changes
Normal -no peaked T's, no QRS widening
Peaked T waves, PR prolongation, wide QRS, sine wave
No risk factors (normal renal function, no culprit drugs, no acidosis)
AKI/CKD, K⁺-sparing drugs, acidosis, rhabdomyolysis, etc.
Symptoms
Patient is asymptomatic, feels well
May have weakness, palpitations, paresthesias
Repeat sample
Normal K⁺ on a free-flowing, non-hemolyzed redraw
Persistently elevated on repeat
Plt/WBC count
Often markedly elevated (thrombocytosis or leukocytosis)
Usually normal or irrelevant
The Key Move
If you suspect pseudohyperkalemia: Redraw blood from a free-flowing venipuncture (no tourniquet or < 1 min), into a green-top (lithium heparin) tube for plasma potassium. This avoids both clotting artifact (thrombocytosis) and most hemolysis artifact. If the plasma K⁺ is normal while the original serum K⁺ was elevated → pseudohyperkalemia confirmed.
Never assume pseudohyperkalemia if the patient has ECG changes. Even if the sample appears hemolyzed, if the ECG shows peaked T waves or QRS widening, treat as true hyperkalemia while redrawing. The cost of treating a false positive (calcium, insulin) is far less than the cost of missing real hyperkalemia (cardiac arrest).
🚨 Management
Treatment Ladder
Three categories of treatment -use them in order: (1) Stabilize the membrane, (2) Shift K⁺ into cells, (3) Remove K⁺ from the body. Only #3 actually lowers total body potassium.
Step
Drug (Brand)
Dose
Onset
Duration
Mechanism
1. STABILIZE
Calcium gluconate FIRST IF ECG CHANGES
1–2 g (10–20 mL of 10%) IV over 2–3 min
1–3 min
30–60 min
Stabilizes cardiac membrane. Does NOT lower K⁺. Repeat in 5 min if ECG unchanged. Use calcium chloride (1g) via central line for more rapid effect.
2a. SHIFT
Insulin + Glucose 1ST LINE SHIFT
Regular insulin 10 units IV + D50 25g (1 amp) IV
15–30 min
4–6 hrs
Insulin drives K⁺ into cells via Na⁺/K⁺-ATPase. Must give dextrose or the patient becomes hypoglycemic (10–75% incidence) AHA Hyperkalemia Guidelines, 2023. Check glucose at 1h and 2h. Give D10 drip if glucose < 250 before insulin.
2b. SHIFT
Sodium bicarbonate
50–100 mEq (1–2 amps) IV over 5 min
15–30 min
2 hrs
Drives K⁺ into cells via H⁺/K⁺ exchange. Most effective if acidotic (pH < 7.2). Minimal effect if pH normal. Avoid in volume overload (sodium load).
2c. SHIFT
Albuterol (nebulized)
10–20 mg nebulized (4–8× standard asthma dose)
15–30 min
2–4 hrs
β₂-mediated K⁺ shift into cells. Drops K⁺ by 0.5–1.0 mEq/L. Watch for tachycardia. Often forgotten -add it to insulin/glucose.
3a. REMOVE
Furosemide (Lasix) IF RENAL FUNCTION OK
40–80 mg IV
30–60 min
6 hrs
Enhances renal K⁺ excretion. Only works if kidneys functional. Give with NS if volume depleted.
3b. REMOVE
Patiromer (Veltassa) CHRONIC
8.4 g PO daily
4–7 hrs
Ongoing
K⁺ binder. NOT for acute emergencies (too slow). Best for chronic hyperK management to allow continuation of ACEi/ARB/MRA. OPAL-HK, 2015
Faster than patiromer. Can be used in acute setting (onset 1–2h). Well-tolerated. HARMONIZE, 2014
3d. REMOVE
Hemodialysis REFRACTORY / SEVERE
Emergent HD
Immediate
Definitive
Most effective K⁺ removal. Drops K⁺ by 1–2 mEq/L per session. Indicated: refractory to medical therapy, anuric patient, K⁺ > 6.5 with ECG changes + CKD/ESKD.
Kayexalate (sodium polystyrene sulfonate) -avoid if possible. Slow onset (hours), questionable efficacy SPS Efficacy Review, 2013, and risk of intestinal necrosis (especially with sorbitol). Patiromer and Lokelma have replaced it. If you must use it: 15–30 g PO or 30–50 g PR, never with sorbitol.
🔄 Updated Practice: Old teaching: sodium polystyrene sulfonate (Kayexalate) for hyperkalemia. This is OUTDATED -kayexalate works slowly (hours to days), has unreliable efficacy, and risks intestinal necrosis (especially with sorbitol). Newer potassium binders -patiromer (Veltassa) and sodium zirconium cyclosilicate (Lokelma) -are faster, safer, and better tolerated. Use these instead for non-emergent K⁺ lowering.
📋 Clinical Example -Hyperkalemia Emergency Management
Patient: 68F with CKD Stage IV on lisinopril (Zestril) + spironolactone (Aldactone), K⁺ 7.1, ECG shows peaked T waves and widened QRS.
Immediate (seconds to minutes -stabilize the heart):
Calcium gluconate 1g IV over 2–3 min → repeat ECG. Does NOT lower K⁺ -stabilizes cardiac membrane. Effect lasts 30–60 min. Repeat if ECG still abnormal.
Shift K⁺ intracellularly (minutes to hours):
Regular insulin 10 units IV + D50 1 amp (25g glucose) -onset 15–30 min, lowers K⁺ by 0.5–1.0. Check glucose q1h × 4h (hypoglycemia risk peaks at 2–4h, give D10 infusion if needed).
Albuterol (ProAir) 10–20mg nebulized -onset 15–30 min, lowers K⁺ by 0.5–1.0. Additive with insulin.
Sodium bicarbonate 50 mEq IV -only if concurrent metabolic acidosis. Limited K⁺-lowering effect alone.
Remove K⁺ from body (hours):
Furosemide (Lasix) 40–80mg IV -if any residual kidney function.
Patiromer (Veltassa) 8.4g PO or sodium zirconium (Lokelma) 10g PO -newer K⁺ binders. Onset hours. Better tolerated than kayexalate.
Hemodialysis -definitive treatment for severe/refractory hyperkalemia or anuric patients.
Fix the cause: Hold lisinopril + spironolactone. Recheck K⁺ in 2h.
Stop the Source
Hold offending medications: ACEi/ARB, spironolactone, trimethoprim, NSAIDs, K⁺-sparing diuretics
Stop all IV potassium (check infusions, TPN, LR has 4 mEq/L K⁺)
Low-K⁺ diet if chronic
Treat underlying
🧪 Workup
Workup
ECG -first test
Repeat K⁺ -rule out hemolysis
BMP
Med review -ACEi, ARB, spironolactone, TMP-SMX
CK -rhabdomyolysis
LDH, UA, PO₄ -TLS
💊 Medications
Medications
Drug
Dose
Route
Notes
Ca gluconate
1g IV/5min
IV
Stabilize. Does NOT lower K⁺.
Insulin
10U+D50
IV
Best shifter. Check glucose 1h.
Albuterol
10-20mg neb
Neb
Additive with insulin
Patiromer (Veltassa)
8.4g daily
PO
GI elimination (preferred). Onset 4–7h.
SZC (Lokelma)
10g PO × 3 doses
PO
GI elimination. Faster onset (~1h). Preferred in acute setting.
Kayexalate (SPS)
15-30g
PO
GI elimination (outdated -prefer patiromer or Lokelma. Risk of intestinal necrosis.)
📋 On Rounds
Pimp Questions
Does calcium gluconate lower potassium?
No. Calcium stabilizes the cardiac membrane by raising the threshold potential -it makes the heart less susceptible to arrhythmia. It does NOT move K⁺ at all. It buys you time (30–60 min) while insulin/glucose and other therapies take effect. That's why you always follow calcium with insulin/glucose.
Why do you need to check glucose after giving insulin for hyperkalemia?
Hypoglycemia occurs in 10–75% of patients treated with insulin for hyperkalemia (higher than most realize). The D50 wears off before the insulin does. Check glucose at 1 hour and 2 hours minimum. Many institutions now use D10 infusion running alongside insulin instead of a single D50 bolus to prevent delayed hypoglycemia.
What's the dose of nebulized albuterol for hyperkalemia?
10–20 mg -that's 4 to 8 times the standard 2.5 mg asthma dose. This is the most commonly underdosed hyperkalemia treatment. At high doses, β₂-mediated Na⁺/K⁺-ATPase activation shifts K⁺ into cells, dropping serum K⁺ by 0.5–1.0 mEq/L. Side effect: tachycardia. Use cautiously with cardiac patients.
What is the onset and duration of each hyperkalemia treatment, and why does the order matter?
(1) Calcium (membrane stabilization): onset 1-3 min, duration 30-60 min. Give first if ECG changes -protects the heart immediately but does NOT lower K⁺. (2) Insulin 10 units + D50 (shift): onset 15-30 min, duration 4-6h. Most reliable K⁺ shifter -lowers K⁺ by 0.5-1.2 mEq/L. Always give D50 concurrently (even if glucose is high -insulin-induced hypoglycemia is the #1 complication)
Clinical Examples
📋 Case 1, Hyperkalemia with ECG Changes from RAAS Inhibitors
Key findings: K⁺ 7.1, ECG: peaked T waves, widened QRS. Cr 4.2 (baseline 3.5), pH 7.32. No hemolysis on repeat sample.
Management:
Calcium gluconate 1g IV over 5 min (membrane stabilization, onset 1-3 min), QRS narrows immediately
Hold lisinopril + spironolactone; nephrology consult for RAAS inhibitor safety reassessment
Teaching point: The combination of ACEi + MRA in CKD is the most common cause of dangerous hyperkalemia. Always recheck K⁺ and Cr within 1 week of starting or uptitrating RAAS inhibitors.
📋 Case 2, Pseudohyperkalemia vs True Hyperkalemia
Patient: 45 y/o F with CML (WBC 180K), routine labs show K⁺ 6.8. Asymptomatic, normal ECG, no prior renal disease.
Key findings: Cr 0.9 (normal), bicarb 24, glucose 105. Sample noted as "slightly hemolyzed." Repeat K⁺ from free-flowing venipuncture without tourniquet: 4.4.
Management:
Recognize pseudohyperkalemia, hemolyzed sample is the #1 cause of spurious K⁺ elevation
Extreme leukocytosis (CML) causes in-vitro K⁺ release from fragile WBCs during clotting
Send plasma K⁺ (heparinized tube, no clotting) for accurate result in leukocytosis
Do NOT treat unless confirmed on repeat and/or ECG changes present
Teaching point: Always recheck before treating. Hemolyzed samples, prolonged tourniquet use, fist clenching, and extreme leukocytosis/thrombocytosis all cause pseudohyperkalemia. Treating a false K⁺ risks iatrogenic hypokalemia.
📋 Case 3, Hyperkalemia from Tumor Lysis Syndrome
Patient: 58 y/o M with newly diagnosed Burkitt lymphoma, K⁺ 7.8 with sine-wave pattern on ECG 12h after starting chemotherapy.
Calcium gluconate 1g IV x2 (sine wave = near-arrest, may need repeat dose)
Emergent dialysis, K⁺ 7.8 with sine wave is refractory-level hyperkalemia
Rasburicase 0.2 mg/kg IV for uric acid (avoid allopurinol in established TLS)
Aggressive IVF for renal protection; avoid calcium-containing solutions (risk of calcium-phosphate precipitation)
Teaching point: TLS causes hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia. Sine-wave pattern on ECG is a pre-arrest rhythm, this patient needs emergent dialysis, not just medical management.
📣 Sample Presentation
One-Liner
"Mr. Russo is a 74-year-old with CKD4 on lisinopril and spironolactone presenting with weakness. K⁺ 7.1. ECG shows peaked T waves and widened QRS."
Key Points to Cover on Rounds
K⁺ 7.1 with ECG changes -emergent management initiated. Calcium gluconate 1g IV (membrane stabilization) → QRS narrowed within 3 min. Insulin 10 units IV + D50 (shift). Albuterol 10 mg continuous neb (shift). Kayexalate 30g PO (elimination). Repeat K⁺ at 1h: 6.2, at 2h: 5.8, ECG normalized. Offending agents: lisinopril and spironolactone held. Nephrology consulted -not meeting urgent dialysis criteria. Plan: serial K⁺ q4h, renally dose medications, nephrology to reassess RAAS inhibitor safety.
RoundsRx Infographic Series · #49 · Renal & Metabolic · PDF 157 KB
⚡ Summary
Summary
Treat the ECG, Not the Number
The progression is peaked T waves, then flattening P waves with a lengthening PR, then a widening QRS, then a sine wave, then VF or asystole.The serum level does not predict where on that path the patient sits: a chronic dialysis patient may tolerate 6.5 quietly while an acute rise at the same level produces a sine wave. Any ECG change makes this an emergency regardless of the number.
Stabilize the Membrane First
Calcium gluconate 1 g IV over 2 to 3 min for any ECG change: onset 1 to 3 min, duration only 30 to 60 min. It restores the gap between resting and threshold potential that hyperkalemia has narrowed, which is why it protects against arrhythmia without lowering the potassium at all. Repeat in 5 min if the ECG has not improved, and redose when the effect wears off if the potassium is still high, because the shifting therapies are slower than the calcium is short-lived.
Shift It In While You Plan Removal
Insulin 10 units IV with D50 is the most reliable shifter: onset 15 to 30 min, drops the level 0.5 to 1 mEq/L. Check glucose hourly for 4 to 6 h afterward, because delayed hypoglycemia is the commonest complication, especially in renal failure where insulin clearance is slow (many protocols halve the dose to 5 units). Albuterol 10 to 20 mg nebulized adds another 0.5 mEq/L, but roughly one patient in five does not respond, so never use it alone. Bicarbonate helps only when there is a metabolic acidosis to correct.
Shifting Buys Time; Only Removal Fixes It
Every shifted ion is still in the body and will come back out. Remove it via the kidney (loop diuretic if making urine), the gut (sodium zirconium cyclosilicate, onset around 1 h, or patiromer, slower; avoid old-style kayexalate with sorbitol, which causes intestinal necrosis), or the machine: dialysis is definitive for the anuric, the refractory, and the massive tissue-release syndromes. Arrange it early; a rebound is expected a few hours after any session as potassium re-equilibrates from cells.
Common Causes, in Order
Impaired excretion leads: CKD and AKI, usually with a drug on top (ACEi/ARB plus spironolactone is the classic pair; add TMP-SMX and NSAIDs to the suspect list). Then shift out of cells (acidosis, insulin deficiency in DKA), then release from cells (rhabdomyolysis, tumor lysis, hemolysis, tissue necrosis). The cause determines the durable fix: stopping the drug, treating the DKA, or dialysis; the acute cocktail is the same regardless.
Pseudohyperkalemia
A hemolyzed sample is the #1 cause of a surprise high potassium: cells lyse in the tube and spill their potassium into the serum. Fist clenching, prolonged tourniquet time, and extreme leukocytosis or thrombocytosis (potassium released during in-tube clotting; a plasma sample corrects it) do the same. Recheck before treating a well patient with a normal ECG and no reason to be hyperkalemic; but if the ECG shows changes, treat first and question the lab later.
📄 One Pager
Nephrology / Emergency · One Pager
Hyperkalemia
ECG changes → calcium gluconate first (stabilize). Then shift (insulin + D50 + albuterol). Then eliminate (patiromer/Lokelma, diuretics, dialysis).
🧪 ECG Progression
Peaked T → flattened P → widened QRS → sine wave → VF/asystole. Treat ECG changes, not the K⁺ number. ECG changes can occur at any level.
GABA receptor downregulation from chronic alcohol use → unopposed excitatory state on cessation. Withdrawal seizures kill. DTs have 15–20% mortality if untreated. Recognize early, treat aggressively.
Visual/auditory/tactile hallucinations with intact sensorium (patient knows they're hallucinating). Not DTs.
12–48 hours
Withdrawal seizures
Generalized tonic-clonic. Brief, self-limited. Risk of status epilepticus. Peak at 24h. Treat with benzodiazepines, NOT phenytoin (phenytoin doesn't work for withdrawal seizures).
48–96 hours
Delirium tremens (DTs)
Altered sensorium (confusion, agitation, global disorientation) + autonomic instability (fever, tachycardia, HTN, diaphoresis) + hallucinations. Mortality 15–20% if untreated.
DTs ≠ hallucinations. Alcoholic hallucinosis has intact sensorium. DTs have global confusion + autonomic storm. This is the key distinction.
Key Evidence: Symptom-triggered benzodiazepine dosing (CIWA-based) reduces total benzo dose and ICU length of stay vs fixed-schedule dosing Saitz, 1994. Phenobarbital loading is a viable alternative for severe/refractory withdrawal Rosenson, 2013. Carbamazepine may reduce seizure risk but is NOT first-line Malcolm, 2002. Dexmedetomidine as adjunct reduces benzo requirements in ICU Mueller, 2014.
🚨 Management
CIWA-Ar Protocol (Symptom-Triggered)
Score 0–67. Assess q1–4h depending on severity. Symptom-triggered dosing reduces total benzo dose and ICU stay vs fixed-schedule dosing Saitz, 1994.
ICU. Lorazepam 4 mg IV q15–30 min until controlled. Consider phenobarbital. Load aggressively.
CIWA-Ar Protocol: Score q1-2h. Score < 10: supportive care (fluids, thiamine, folate, electrolytes). Score 10-18: moderate withdrawal - chlordiazepoxide 25-50 mg PO q6h or diazepam 5-10 mg IV q5-15min. Score > 18: severe - diazepam 10-20 mg IV q5-15min until CIWA < 10. If > 200 mg diazepam without control = benzo-resistant - add phenobarbital 130-260 mg IV Gold, 2007.
Treatment Agents
Drug (Brand)
Dose
Role
Key Notes
Lorazepam (Ativan) 1ST LINE
1–4 mg IV q1h PRN (CIWA-guided)
First-line benzodiazepine.
No active metabolites (preferred in liver disease over diazepam). Propylene glycol toxicity with prolonged high-dose infusion.
Diazepam (Valium) 1ST LINE
5–20 mg IV/PO q1h PRN
Alternative to lorazepam. Long-acting.
Active metabolites (accumulate in liver failure). Longer duration = smoother withdrawal. Often preferred for outpatient tapers.
Chlordiazepoxide (Librium) MILD-MODERATE
25–100 mg PO q6h, taper over 3–5 days
Mild-moderate withdrawal (CIWA < 15). Oral only.
Long half-life (24–48h) with active metabolites → built-in self-taper, smoother withdrawal. No IV formulation -cannot use in severe withdrawal, NPO, or vomiting. Avoid in liver disease (active metabolites accumulate -use lorazepam instead). Ideal for low-risk floor patients on a fixed taper protocol.
Phenobarbital 1ST LINE / SEVERE
Load: 130–260 mg IV q15–30 min until controlled (total 10–20 mg/kg). Maintenance: 32–65 mg IV q6–8h.
Emerging first-line for severe AWS. Shorter ICU & hospital LOS vs benzos.
GABA-A agonist at different site than benzos, synergistic. Long half-life (80–120h) → self-tapering. Monitor for respiratory depression. Kessel, 2024: shorter LOS (2.8 vs 4.7 days), less ICU time, less mechanical ventilation vs benzos. Many centers now use front-loaded phenobarbital as primary agent for severe withdrawal Gold, 2007.
Dexmedetomidine (Precedex) ADJUNCT
0.2–1.5 mcg/kg/hr IV
Adjunct only -NOT a standalone.
Reduces autonomic symptoms (tachycardia, HTN, agitation). Does NOT prevent seizures or DTs -always co-administer with a GABA agonist (benzo or phenobarbital).
Thiamine (Vitamin B1) GIVE FIRST
500 mg IV TID × 3 days (high-dose Caine protocol if Wernicke suspected) or 100 mg IV daily minimum
Give BEFORE any glucose.
Glucose metabolism depletes thiamine → precipitates Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia). Give thiamine to ALL alcohol withdrawal patients.
Phenytoin does NOT work for alcohol withdrawal seizures. The mechanism is GABA-related, not sodium channel. Benzos and phenobarbital are the only effective agents. Do not waste time loading phenytoin.
🔄 Updated Practice: Old teaching: phenytoin (Dilantin) prevents or treats alcohol withdrawal seizures. This is WRONG -phenytoin does NOT work for withdrawal seizures and should NOT be used. Benzodiazepines (lorazepam, diazepam) are the treatment. For benzo-resistant withdrawal, phenobarbital is the escalation agent (not phenytoin). Front-loaded phenobarbital protocols are now used as first-line in many centers. Kessel 2024 showed phenobarbital reduced hospital LOS by nearly 2 days and decreased need for mechanical ventilation vs benzodiazepines.
📋 Clinical Example -CIWA-Guided Benzodiazepine Protocol
Lorazepam (Ativan) 1mg IV. Reassess -trending down, good sign.
Hour 4
10
Lorazepam (Ativan) 1mg IV.
Hour 6
7
Hold. Below threshold. Monitor q2h.
Hour 12
5
Continue monitoring. Total lorazepam = 6mg in first 6h.
Red flags to escalate: CIWA > 20 despite treatment → increase frequency/dose → consider phenobarbital load (130–260mg IV q15–30min). Seizure → lorazepam 4mg IV STAT (NOT phenytoin -doesn't work for withdrawal seizures). Hallucinations with clear sensorium = alcoholic hallucinosis (not DTs). DTs = altered sensorium + autonomic storm → ICU + aggressive benzos/phenobarbital.
When to use Chlordiazepoxide (Librium) instead: CIWA < 15, able to take PO, no liver disease, low risk for DTs → fixed taper 25–100mg PO q6h over 3–5 days. Smoother withdrawal due to long half-life. Floor patients only.
🧪 Workup
Workup
CIWA-Ar score
CBC, BMP, Mg, PO₄
LFTs, INR, albumin
Lipase
Blood alcohol level
CT head if AMS/focal deficit/head injury
💊 Medications
Medications
Drug
Dose
Route
Notes
Lorazepam
1-4mg IV q1h PRN
IV
CIWA≥8. Preferred liver disease.
Diazepam
10-20mg IV
IV
Long-acting. Caution liver.
Chlordiazepoxide (Librium)
25-100mg PO q6h taper
PO only
Mild-mod (CIWA<15). No IV form. Avoid liver disease.
Phenobarbital
130-260mg IV
IV
Benzo-resistant
Thiamine
500mg IV×3d
IV
BEFORE glucose
MgSO₄
2-4g IV
IV
Replace aggressively
📋 On Rounds
Pimp Questions
What is the advantage of phenobarbital over benzodiazepines in severe AWS?
Phenobarbital acts at a different GABA-A binding site than benzodiazepines -it increases the duration of Cl⁻ channel opening (vs benzos which increase frequency). This provides more predictable, dose-dependent GABA agonism. Its 80–120h half-life creates a built-in self-taper. Front-loading phenobarbital reduces total benzo dose, ICU days, and intubation rates.
Why must you give thiamine before glucose?
Thiamine (B1) is a cofactor for pyruvate dehydrogenase and α-ketoglutarate dehydrogenase -essential for aerobic glucose metabolism. Giving glucose to a thiamine-depleted patient shunts all remaining thiamine into metabolism, acutely precipitating Wernicke encephalopathy (confusion, ophthalmoplegia, ataxia). If Wernicke is untreated, it progresses to Korsakoff syndrome (irreversible anterograde amnesia, confabulation). Always thiamine first.
When should you use Chlordiazepoxide (Librium) vs Lorazepam (Ativan) in alcohol withdrawal?
Chlordiazepoxide (Librium) is ideal for mild-moderate withdrawal (CIWA < 15) in patients who can take oral meds and are NOT at high risk for DTs/seizures. Its long half-life (24–48h) with active metabolites provides a smoother, self-tapering withdrawal. However: (1) No IV formulation → can't use in severe withdrawal, NPO, or vomiting, (2) Active metabolites accumulate in liver disease → avoid, (3) Oral only = floor patients only.
What are the risk factors for developing delirium tremens?
DTs develop in only 3-5% of alcohol withdrawal -but carry 5-15% mortality if untreated. Risk factors: (1) Prior DTs (strongest predictor -50% recurrence rate), (2) Prior withdrawal seizures, (3) Heavy daily alcohol use (> 8 drinks/day), (4) Prolonged drinking duration, (5) Concurrent illness (infection, surgery, trauma -any physiologic stress), (6) Older age, (7) Abnormal liver function, (8) High initial CIWA score (> 20).
What is the role of phenobarbital in alcohol withdrawal?
Phenobarbital is increasingly used as an alternative or adjunct to benzodiazepines for severe withdrawal. Advantages: longer half-life (80-120h, self-tapering), effective in benzo-resistant withdrawal, less cross-tolerance. Loading dose: 130-260 mg IV q15-30min titrated to effect. Rosenson, 2013 showed single-dose phenobarbital reduced ICU admissions.
Clinical Examples
📋 Case 1, Moderate Alcohol Withdrawal with CIWA Protocol
Patient: 48M with daily vodka use (1 pint/day x 15 years), admitted for cellulitis. Last drink 16 hours ago. Reports tremor, anxiety, nausea. No prior seizures or DTs.
Key findings: HR 108, BP 152/94, Temp 37.6°C, diaphoretic, bilateral hand tremor, mildly anxious but oriented. CIWA score: 18 (moderate). Magnesium 1.4, phosphorus 2.0, AST 180, ALT 95.
Management:
CIWA-based symptom-triggered protocol: diazepam 10-20 mg PO q1h for CIWA ≥ 10 Saitz, 1994
Symptom-triggered dosing is superior to fixed-schedule: less total benzo, shorter treatment
Replete: magnesium sulfate 2g IV, thiamine 500 mg IV x 3 days (give BEFORE glucose), folate 1 mg, multivitamin
Banana bag is inadequate: only contains 100 mg thiamine. Order high-dose thiamine separately
Teaching point: CIWA-based symptom-triggered therapy is the standard of care. Always give high-dose IV thiamine (500 mg) before any glucose-containing fluids. Banana bags contain inadequate thiamine for prophylaxis.
📋 Case 2, Delirium Tremens Refractory to Benzodiazepines
Patient: 55M with history of prior DTs and withdrawal seizures, admitted 48 hours ago with CIWA protocol. Now acutely agitated, hallucinating (seeing insects on walls), febrile, and tachycardic despite receiving diazepam 120 mg over past 6 hours.
Key findings: Temp 39.1°C, HR 138, BP 170/100, diaphoretic, globally confused, visual hallucinations, gross tremor. CIWA not assessable. CK 2,400 (rhabdomyolysis from agitation).
Management:
ICU transfer: benzo-refractory DTs require ICU. Switch to IV midazolam or diazepam drip
Add phenobarbital 130-260 mg IV q15-30min for benzo-resistant withdrawal Rosenson, 2013
Dexmedetomidine drip as adjunct (reduces benzo requirement) -- NOT as monotherapy
Aggressive IV hydration for rhabdomyolysis (target UOP 200-300 mL/hr), monitor CK, Cr, potassium
Teaching point: In DTs, benzodiazepine tolerance can be extreme (>1000 mg diazepam equivalents). Phenobarbital is the key second-line agent. Never use dexmedetomidine or propofol as monotherapy -- they do not prevent seizures.
Delirium Tremens is a medical emergency. Mortality 15-20% if untreated, < 5% with aggressive treatment. Do NOT undertreat - there is no maximum benzo dose for DTs. If standard doses fail, consider: propofol infusion (for intubated patients), phenobarbital loading, or dexmedetomidine adjunct. ICU admission mandatory. DTs peak at 48-96h after last drink but can occur up to 7 days later.
📋 Case 3, Alcohol Withdrawal Seizure
Patient: 39M brought by EMS after witnessed generalized tonic-clonic seizure at home. Wife reports he quit drinking 2 days ago (12+ beers daily). Seizure lasted ~90 seconds, now postictal.
Key findings: Postictal: drowsy, confused, HR 118, BP 148/92, Temp 37.8°C, tongue laceration. No focal deficits. Glucose 95. No history of epilepsy. Blood alcohol level 0. Last drink ~36 hours ago.
Management:
Immediate: lorazepam 2-4 mg IV to prevent recurrent seizure (withdrawal seizures recur in ~25% within 6-12 hours)
Start long-acting benzodiazepine: diazepam or chlordiazepoxide loading. Phenytoin is NOT effective for withdrawal seizures
CT head if: first seizure, focal features, prolonged postictal state, head trauma, or anticoagulated
HIGH risk for DTs: withdrawal seizure + heavy daily use. Admit to monitored bed, aggressive benzo protocol, CIWA q1h
Teaching point: Alcohol withdrawal seizures peak at 12-48 hours and are typically generalized tonic-clonic. Phenytoin does NOT prevent recurrent withdrawal seizures -- only benzodiazepines work. A withdrawal seizure is a major risk factor for progression to DTs (onset 48-96h).
Phenytoin does NOT work for withdrawal seizures. Alcohol withdrawal seizures are caused by GABA downregulation, not epileptic foci. Phenytoin blocks sodium channels but does not address the GABA deficit. Benzodiazepines are the ONLY first-line treatment for withdrawal seizures. If seizing: lorazepam 2-4 mg IV, repeat q5min as needed Rathlev, 1994.
📣 Sample Presentation
One-Liner
"Mr. O'Brien is a 48-year-old with daily vodka use (1 pint/day × 20 years) who last drank 18 hours ago, presenting with tremor, tachycardia, diaphoresis, and mild agitation. CIWA score 22."
Key Points to Cover on Rounds
CIWA 22 (moderate-severe). Symptom-triggered benzodiazepine protocol: lorazepam 2 mg IV given × 3 in first 6 hours. CIWA trending 22→18→14. No seizure, no hallucinations. Thiamine 500 mg IV daily × 3 days, then 100 mg PO (given BEFORE glucose). Folate 1 mg, MVI. Electrolytes: Mg 1.2 (repleted), K 3.4 (repleted), PO₄ 2.0 (repleted). Total benzos in 24h: 14 mg lorazepam-equivalents. Plan: continue CIWA protocol, watch for DTs (peak risk 48-72h), SW and addiction medicine consulted.
Monitoring
CIWA q1-2h
Vitals q1-4h
Mg, K, PO₄ q12h
Seizure precautions
DT watch 48-72h
Blood glucose
⚡ Summary
Summary
Understand the Mechanism
Chronic alcohol downregulates GABA receptors and upregulates NMDA receptors, so cessation leaves an unopposed excitatory state. That is why benzodiazepines work (they restore GABA tone) and why the syndrome escalates rather than plateaus if it is under-treated.
Know the Timeline
6 to 12 h: tremor, anxiety, sweating, tachycardia.12 to 24 h: alcoholic hallucinosis.24 to 48 h: withdrawal seizures.48 to 96 h: delirium tremens.The timeline tells you what to watch for next, and a patient at 36 h is not out of the woods.
Hallucinosis Is Not DTs
Alcoholic hallucinosis has an intact sensorium: the patient knows where they are and often knows the hallucinations are not real.DTs have global confusion plus an autonomic storm.That distinction is the key one, because hallucinosis is not the emergency and DTs carry 15 to 20% mortality untreated.
Use Symptom-Triggered Dosing
Score CIWA-Ar every 1 to 2 h and dose to the score.This reduces total benzodiazepine exposure and ICU length of stay compared with fixed scheduled dosing (Saitz). CIWA is invalid in a patient who cannot communicate, including the intubated and the delirious, so use RASS-based or fixed protocols there instead.
Escalate Aggressively in Severe Withdrawal
CIWA above 18 means IV diazepam 10 to 20 mg every 5 to 15 min until controlled.Under-dosing is the commonest error: withdrawal that is chased rather than suppressed progresses to seizures and DTs. Front-loading with a long-acting agent gives a self-tapering effect through its active metabolites.
Add Phenobarbital When Benzodiazepines Fail
Above about 200 mg of diazepam without control means benzodiazepine-resistant withdrawal.Phenobarbital 130 to 260 mg IV works at a different site on the GABA receptor and increases channel opening duration rather than frequency, so it succeeds where more benzodiazepine will not. Its long half-life gives an inherent taper.
Choose the Benzodiazepine for the Liver
Diazepam and chlordiazepoxide are long-acting and self-tapering, and are preferred in most patients.Lorazepam in significant liver disease and in the elderly, because it is glucuronidated rather than oxidized and so does not accumulate. Avoid antipsychotics as monotherapy: they lower the seizure threshold and do not treat the underlying withdrawal.
Do Not Forget Thiamine and the Electrolytes
Give thiamine before any glucose, since a glucose load in a thiamine-deficient patient precipitates Wernicke encephalopathy. Replace magnesium, potassium and phosphate, and watch for refeeding syndrome. Look for the illness underneath: infection, pancreatitis, GI bleeding, subdural hematoma and hepatic encephalopathy all masquerade as, or coexist with, withdrawal, and starting medication for alcohol use disorder before discharge is the intervention that changes what happens next.
Inflammation of the pancreas -ranges from mild edematous disease (80%, self-limited) to severe necrotizing pancreatitis (20%, multiorgan failure, ICU mortality 15–30%). Aggressive early fluids + pain control + early feeding.
🔍 Overview
Diagnosis (Revised Atlanta -need 2 of 3)
Abdominal pain consistent with pancreatitis (epigastric, radiating to back, worse supine)
Lipase ≥ 3× upper limit of normal (more sensitive and specific than amylase)
Imaging findings on CT/MRI/US (only needed if diagnosis unclear from above two)
Do NOT routinely CT on admission. CT is normal in 15–30% of early pancreatitis. Reserve CT for: diagnostic uncertainty, no improvement at 48–72h, or suspecting complications (necrosis, abscess, pseudocyst).
Transient organ failure (< 48h) OR local complications (necrosis, pseudocyst, fluid collections)
~5%
Severe (~5%)
Persistent organ failure > 48h (respiratory, renal, cardiovascular)
15–30%
BISAP score ≥ 3 within 24h predicts severe disease: BUN > 25, Impaired mental status, SIRS, Age > 60, Pleural effusion.
🚨 Management
Pillars of Management
1. Goal-directed IVF
Lactated Ringer's preferredde-Madaria, 2018. Goal-directed: 1.5 mL/kg/hr initially, titrate to UOP ≥ 0.5 mL/kg/hr, HR < 120, MAP ≥ 65. Reassess at 6h -avoid over-resuscitation (worsens third-spacing, pulmonary edema). Recent data suggests moderate fluids are non-inferiorWATERFALL, 2022: aggressive vs moderate fluids → moderate (1.5 mL/kg/hr) was non-inferior with fewer fluid complications.
2. Pain Control
Multimodal analgesia. Acetaminophen IV 1g q6h (scheduled) + fentanyl or hydromorphone IV PRN (morphine is acceptable -the "morphine causes sphincter of Oddi spasm" concern is not clinically significant). Ketorolac 15–30 mg IV q6h if no AKI. PCA if severe.
3. Early Feeding
Start oral diet within 24h if tolerated. Low-fat solid diet (not just clear liquids). Petrov, 2013: early feeding reduces infection, organ failure, and length of stay. NPO is outdated. If oral not tolerated → nasogastric or nasojejunal tube feeding preferred over TPN. TPN only if enteral feeding fails ≥ 5 days.
4. Antibiotics
NOT routine in acute pancreatitis -even if necrosis present. Prophylactic antibiotics for necrotizing pancreatitis do NOT reduce mortality or infection Dellinger, 2007. Only treat infected necrosis (confirmed by FNA with positive gram stain/culture, or gas on CT). Use carbapenems (meropenem) -best pancreatic penetration.
5. Gallstone Pancreatitis
ERCP within 24h ONLY if concurrent cholangitis (fever, jaundice, RUQ pain = Charcot's triad) or persistent biliary obstruction. Otherwise, cholecystectomy during same admission (before discharge) to prevent recurrence PONCHO, 2015.
🔄 Updated Practice: Several old practices have been abandoned: (1) Prophylactic antibiotics do NOT prevent infected necrosis -don't give them. (2) NPO until pain resolves and lipase normalizes is WRONG -start low-fat oral diet as soon as tolerated (early feeding shortens hospital stay). (3) Old teaching said "aggressive" IV fluids (250-500 mL/hr); WATERFALL 2022 showed aggressive LR did not improve outcomes and increased fluid overload. Use goal-directed fluid resuscitation instead (1.5 mL/kg/hr LR, targeting UOP ≥0.5 mL/kg/hr).
Complications
Two questions classify every local complication (Revised Atlanta 2012). First, is there necrosis? That decides whether a drain alone can ever be enough, because solid debris clogs a percutaneous catheter and needs necrosectomy. Second, is it under or over 4 weeks? That decides whether a mature wall exists to drain into. Those two answers produce the four collections below, and they dictate what you are allowed to do.
Local Complications: The Four Collections
Collection
Timing
What it contains
Management, and why
Acute peripancreatic fluid collection (APFC)
< 4 weeks no necrosis
Fluid only, homogeneous, no defined wall
Leave it alone. Most resolve spontaneously, and instrumenting a sterile collection is the classic way to convert it into an infected one.
Pancreatic pseudocyst
> 4 weeks no necrosis
Encapsulated fluid only, defined enhancing wall, no solid debris
Drain only if symptomatic (pain, gastric outlet or biliary obstruction) or infected, by EUS-guided transmural route. Size alone is not an indication: the old "> 6 cm for > 6 weeks" rule is obsolete, because most large pseudocysts still regress and draining an asymptomatic one only risks infecting it.
Acute necrotic collection (ANC)
< 4 weeks necrosis
Fluid plus solid necrotic debris, heterogeneous, no wall yet
Supportive care. With no wall it will not hold a drain, and solid debris clogs a percutaneous catheter, so early drainage tends to leak and buy nothing.
Walled-off necrosis (WON)
> 4 weeks necrosis
Encapsulated fluid plus solid debris, mature wall
Intervene only if infected, or if sterile but causing persistent pain, obstruction, or failure to thrive. That mature wall is what makes drainage and necrosectomy safe, and is the whole reason to wait 4 weeks.
Infected Necrosis
The commonest cause of late death in pancreatitis, and the one complication where timing beats aggression.
Suspect it after the first week. It complicates about a third of necrotizing pancreatitis, peaking at weeks 2 to 4 as gut organisms translocate. The trigger to act is clinical deterioration, or failure to improve after 7 to 10 days.
Gas within the collection on CT is diagnostic.Routine FNA is no longer recommended: it carries a real false-negative rate and rarely changes a decision you can already make clinically.
Choose antibiotics that actually reach necrotic tissue, since poor perfusion excludes most agents: a carbapenem, or a fluoroquinolone plus metronidazole, narrowed once cultures return. In a stable patient antibiotics alone may be the entire treatment: in POINTER, 2021, 19 of 49 postponed-arm patients (39%) were cured without any drainage at all.
Step up, never straight to open surgery.PANTER, 2010 compared a step-up approach (drain first, minimally invasive necrosectomy only if no improvement) against open necrosectomy: major complications or death 40% vs 69% (RR 0.57, 95% CI 0.38 to 0.87, P = 0.006), driven by new-onset organ failure 12% vs 42%. Mortality itself did not differ (19% vs 16%), and about 35% never needed necrosectomy because the drain alone was definitive.
Postpone the drain if the patient will tolerate it. POINTER's primary endpoint was negative (no difference in complications or mortality), so the case for waiting rests on fewer interventions, not on survival. Practically: antibiotics and wait for the wall, but early drainage remains legitimate in a deteriorating patient, because it did not cause harm.
Do not intervene on sterile necrosis unless it is symptomatic. Extent of necrosis alone never justifies intervention.
Systemic and Vascular Complications
Complication
Timing
Management, and why
Persistent organ failure defines severe disease
First week
SIRS progressing to organ failure beyond 48 hours is what defines severe disease on the Revised Atlanta scale and what kills in the early mortality peak. Expect ARDS, AKI, and distributive shock. Late deaths are a separate mechanism: infected necrosis and sepsis.
Abdominal compartment syndrome
First days, with resuscitation
Sustained intra-abdominal pressure > 20 mmHg with new organ dysfunction (WSACS); intra-abdominal hypertension starts at ≥ 12 (grade I 12 to 15, II 16 to 20, III 21 to 25, IV > 25). Driven by ileus, retroperitoneal edema, ascites, and over-resuscitation, which is a second reason to keep fluids moderate. Measure it rather than eyeballing it: bladder pressure with ≤ 25 mL instilled saline, supine, at end-expiration, transducer at the midaxillary line. Decompress medically first (NG and rectal decompression, prokinetics, sedation and if needed paralysis, percutaneous drainage of tense ascites, stop the fluid), since each lowers pressure without opening the abdomen. Decompressive laparotomy is reserved for overt ACS, because an open abdomen carries fistula, hernia, and failed-closure morbidity you cannot take back.
Splanchnic vein thrombosis ~22% of necrotizing pancreatitis
Variable
Most often the splenic vein, producing left-sided portal hypertension with isolated gastric varices. Anticoagulation is individualized against bleeding risk rather than automatic. Splenectomy for refractory variceal bleeding.
Splenic artery pseudoaneurysm
Weeks, with necrosis
Enzymatic erosion of the vessel wall. The warning signs are a sentinel bleed, an unexplained hemoglobin drop, or blood in a drain. Treat by angioembolization, not laparotomy, because operating in an inflamed necrotic field carries far higher mortality.
Disconnected pancreatic duct syndrome
Late, with necrosis
Necrosis of the neck transects the duct, so a viable upstream tail keeps secreting into a dead end. Suspect it when a collection recurs every time the drain comes out. It needs an indefinite transmural stent or surgery, and missing it means an endless cycle of re-drainage.
Exocrine insufficiency and new diabetes
Months
Common after necrotizing disease, so arrange follow-up rather than discharging to nobody. Check fecal elastase for exocrine failure and start pancreatic enzyme replacement if low; screen for new diabetes.
📋 Clinical Example -Acute Pancreatitis Severity Assessment
Patient: 52M heavy drinker, epigastric pain radiating to back × 12h, lipase 2,400 (>3× ULN), HR 105, Cr 1.8.
Initial management:
Goal-directed IV LR at 1.5 mL/kg/hr (WATERFALL, 2022 -'aggressive' fluid strategy did not improve outcomes and increased fluid overload. Use goal-directed approach: target UOP ≥ 0.5 mL/kg/hr, trending BUN and hematocrit). NOT NS -LR reduces SIRS in pancreatitis.
NPO initially → start low-fat diet as soon as tolerated (early feeding improves outcomes -do NOT wait for pain to fully resolve or lipase to normalize).
Pain: IV hydromorphone (Dilaudid) 0.5–1mg q3h PRN. Morphine is safe despite old myths about sphincter of Oddi spasm.
NO prophylactic antibiotics (even in severe pancreatitis -doesn't prevent infected necrosis).
Severity assessment at 48h:
BISAP score: BUN > 25 (+1), impaired mental status (+0), SIRS (+1), age > 60 (+0), pleural effusion (+0) = 2 → moderate risk.
CT only if: not improving by day 3–5, or concern for complications (necrosis, pseudocyst, abscess). Do NOT CT on admission -necrosis takes 48–72h to develop.
When do you give antibiotics in acute pancreatitis?
Only for infected necrosis. Prophylactic antibiotics for necrotizing pancreatitis showed no benefit in multiple RCTs. Sterile necrosis is managed supportively. Suspect infection if: worsening at > 7–10 days, new fever/leukocytosis, gas in necrotic collection on CT. Confirm with FNA. Treat with meropenem (best penetration into pancreatic tissue).
Why LR over NS for pancreatitis resuscitation?
de-Madaria, 2018: LR reduced SIRS at 48h compared to NS. The mechanism: NS causes hyperchloremic metabolic acidosis (high chloride load), which may worsen pancreatic inflammation. LR is more physiologic (contains lactate buffer, less chloride). This is consistent with broader critical care data favoring balanced crystalloids SMART, 2018.
A patient has pancreatitis with TG level of 2,800 mg/dL. How does this change management?
Hypertriglyceridemia-induced pancreatitis (TG typically > 1,000 mg/dL). Management additions beyond standard care: (1) Insulin drip (regular insulin 0.1-0.3 units/kg/hr) -insulin activates lipoprotein lipase → rapidly clears triglycerides. Target TG < 500. Add dextrose to prevent hypoglycemia. (2) NPO strictly until TG < 500 (dietary fat would raise TG further). (3) Fibrate therapy (fenofibrate or gemfibrozil)
When do you order MRCP vs ERCP in gallstone pancreatitis?
MRCP (magnetic resonance cholangiopancreatography): non-invasive imaging to evaluate the common bile duct for stones. Order when: labs suggest choledocholithiasis (elevated bilirubin, dilated CBD on US) but patient is stable and not cholangitic. MRCP visualizes stones without procedural risk. If MRCP shows CBD stone → ERCP for stone removal. If MRCP negative → cholecystectomy without ERCP.
Clinical Examples
📋 Case 1, Gallstone Pancreatitis with Cholangitis
Patient: 52 y/o F with cholelithiasis, presents with severe epigastric pain radiating to the back, fever 39.4°C, and jaundice.
Key findings: HR 118, BP 96/58. Lipase 5,200, total bilirubin 6.8, direct 5.2, ALP 420, WBC 19K. RUQ US: gallstones, CBD dilated to 11 mm.
Management:
Charcot's triad present (fever + jaundice + RUQ pain), emergent ERCP within 24h (do not wait for MRCP)
IV antibiotics: pip-tazo 4.5g q6h (biliary source with sepsis)
Moderate, goal-directed IVF with LR at 1.5 mL/kg/hr (bolus 10 mL/kg only if hypovolemic), titrated to UOP ≥ 0.5 mL/kg/hr. Do NOT run 3 mL/kg/hr: that was the aggressive arm WATERFALL stopped early for harm (fluid overload 20.5% vs 6.3%) with no benefit WATERFALL, 2022
Cholecystectomy this admission once inflammation resolves
Teaching point: Cholangitis requires urgent ERCP (within 24h), do not waste time with MRCP when Charcot's triad is present. Use MRCP only when choledocholithiasis is suspected but the patient is stable and not cholangitic.
📋 Case 2, Hypertriglyceridemia-Induced Pancreatitis
Patient: 38 y/o M with poorly controlled DM2 and obesity, presents with severe epigastric pain. No alcohol use, no gallstones.
Long-term: fenofibrate, very low-fat diet (< 20g/day), glycemic control
Teaching point: TG-induced pancreatitis (TG > 1,000) requires insulin drip for rapid TG clearance. Unlike gallstone pancreatitis, keep strictly NPO until TGs are controlled. Consider plasmapheresis if TG > 5,000 or refractory to insulin.
📋 Case 3, Necrotizing Pancreatitis with Infected Necrosis
Patient: 60 y/o M with alcohol-induced pancreatitis, initially improving then develops new fever and leukocytosis at day 10.
Key findings: CT abdomen: 40% pancreatic necrosis with gas bubbles in the necrotic collection. WBC 24K (was trending down), fever 38.8°C, procalcitonin rising.
Management:
Gas in necrotic collection = infected necrosis until proven otherwise
Meropenem 1g IV q8h (best pancreatic tissue penetration of any antibiotic)
CT-guided FNA of collection for culture confirmation
Interventional radiology for percutaneous drain; step-up approach preferred over early surgical necrosectomy PANTER, 2010
Teaching point: Prophylactic antibiotics for sterile necrotizing pancreatitis have no benefit. Antibiotics are indicated ONLY for infected necrosis (suspect at day 7-10+ if clinical worsening). The step-up approach (drain first, surgery only if needed) is superior to early surgery.
📣 Sample Presentation
One-Liner
"Mrs. Garcia is a 45-year-old presenting with severe epigastric pain radiating to the back × 12 hours after a fatty meal. Lipase 4,200. RUQ US shows gallstones with CBD dilation to 8 mm. BISAP score 1."
Key Points to Cover on Rounds
Acute gallstone pancreatitis. Lipase 4,200 (>3× ULN). BISAP 1 (low severity). Treatment: moderate goal-directed IVF with LR (1.5 mL/kg/hr, bolus only if hypovolemic), pain control with hydromorphone 0.5 mg IV PRN. Diet: early oral feeding initiated (clear liquids, advancing as tolerated -don't keep NPO). RUQ US: gallstones, CBD 8 mm → MRCP ordered to evaluate for choledocholithiasis. If CBD stone confirmed → ERCP before cholecystectomy. Surgery consulted for cholecystectomy this admission. CRP trending for severity.
Lipase trend
BMP q12-24h
Ca²⁺ -hypoCa=severe
UOP
Oral intake tolerance
CRP 48h
⚡ Summary
Summary
Diagnose on Two of Three
Characteristic epigastric pain radiating to the back, lipase or amylase at least 3 times the upper limit, or characteristic imaging.Lipase level does not correlate with severity, so a very high value in a well patient is not a reason for the ICU, and a modest rise in a sick one is not reassurance.
Do Not CT on Admission
CT is normal in 15 to 30% of early pancreatitis, because necrosis takes 72 h or more to declare itself. Reserve it for diagnostic uncertainty, no improvement at 48 to 72 h, or suspected complications. An early scan gives a falsely reassuring picture and contributes nothing to management.
I GET SMASHED, but Really Two Causes
Gallstones and alcohol account for roughly 70 to 80%. The rest: hypertriglyceridemia (above 1,000 mg/dL), hypercalcemia, ERCP, trauma, drugs, autoimmune, scorpion sting, mumps. Get a right upper quadrant ultrasound in everyone, and check triglycerides and calcium when the ultrasound is clean, since both are treatable at the cause.
Fluids, Analgesia, Early Feeding
Moderately aggressive lactated Ringer, preferred over normal saline, titrated to perfusion rather than to a fixed volume, since over-resuscitation causes its own harm including abdominal compartment syndrome. Treat pain properly; opioids do not worsen pancreatitis.Feed within 24 h as tolerated, going straight to a low-fat solid diet rather than up a liquid ladder.
No Prophylactic Antibiotics
They do not prevent infected necrosis and they select resistant organisms and fungi.Treat only proven or strongly suspected infection, and suspect infected necrosis when a patient deteriorates after 7 to 10 days, with gas in the collection on CT the specific sign.
Grade Severity Early and Reassess
Revised Atlanta: mild (no organ failure, no complications), moderately severe (transient organ failure under 48 h or local complications), severe (persistent organ failure beyond 48 h).Persistent organ failure is what drives mortality, which reaches 15 to 30% in severe disease, so the 48-hour reassessment matters more than the admission score.
Know the Collections and When to Touch Them
Acute peripancreatic fluid collection and acute necrotic collection in the first 4 weeks; pseudocyst and walled-off necrosis after 4 weeks.Drain for infection, obstruction or refractory symptoms, not for size alone: the old rule of draining any pseudocyst above 6 cm is obsolete. Delay intervention until the collection is walled off, and use a step-up approach of percutaneous or endoscopic drainage before surgical necrosectomy (PANTER, POINTER).
Prevent the Next Episode Before Discharge
Gallstone pancreatitis needs cholecystectomy during the same admission, since recurrence without it is 25 to 30%. Alcohol-related disease needs a cessation intervention started in hospital.Hypertriglyceridemic disease needs a fibrate and dietary management, plus insulin or apheresis acutely. Also watch for the systemic complications: ARDS, acute kidney injury, DIC and abdominal compartment syndrome.
RoundsRx Infographic Series · #37 · Gastro & Hepatology · PDF 167 KB
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GI · One Pager
Acute Pancreatitis
2 of 3: epigastric pain + lipase > 3× + imaging findings. Moderate goal-directed IVF (1.5 mL/kg/hr LR) + pain control + early feeding. No prophylactic antibiotics. Cholecystectomy this admission if gallstone.
🧪 Diagnosis
2 of 3: (1) characteristic epigastric pain radiating to back, (2) lipase > 3× ULN, (3) imaging findings. Lipase preferred over amylase (more specific).
🚨 Management
Moderate goal-directed IVF (LR, 1.5 mL/kg/hr). Pain control (multimodal). Early oral feeding as tolerated (don't keep NPO). No prophylactic antibiotics. Monitor for organ failure.
💊 Etiology Workup
Gallstones (#1): RUQ US + LFTs. Alcohol (#2). TG > 1000: insulin drip + fibrates. If unclear: MRCP, IgG4 (autoimmune), genetic testing. ERCP only if cholangitis.
💊 Key Drugs
LR250-500 mL/hr initially
Hydromorphone0.5-1 mg IV PRN
APAP/ketorolacMultimodal adjuncts
Insulin dripIf TG-induced
⚠️ Pitfalls
Keeping patient NPO (early feeding is safe + beneficial)
Prophylactic antibiotics (no benefit, promotes resistance)
Missing gallstone as cause (US + LFTs in all patients)
Not doing cholecystectomy this admission for gallstone pancreatitis
Time is brain. Every minute of ischemia = ~1.9 million neurons lost. Know the tPA window, thrombectomy criteria, NIHSS-driven antiplatelet choice, and BP targets cold. You will not have time to look them up mid-code stroke.
🔍 Overview
Time Windows
Intervention
Window
Key Criteria
Trial
IV alteplase (tPA) 1ST LINE
≤ 4.5 hours from last known well (LKW)
0.9 mg/kg IV (max 90 mg). 10% bolus over 1 min, 90% infusion over 60 min. No anticoagulants or antiplatelets × 24h post.
NINDS, 1995ECASS III, 2008
IV tenecteplase EMERGING FIRST-LINE
≤ 4.5 hours
0.25 mg/kg IV single bolus (no infusion, push-and-go). Easier, faster, saves ~5 min vs alteplase.
AcT, 2022: tenecteplase non-inferior to alteplase. Now preferred at many stroke centers.
Mechanical thrombectomy LVO
≤ 24 hours (with perfusion imaging 6–24h)
Large vessel occlusion (LVO): ICA, M1, M1-equivalent, basilar. NIHSS ≥ 6. ≤ 6h: CTA showing LVO is sufficient MR CLEAN, 2015ESCAPE, 2015. 6–24h: requires perfusion mismatch on CT perfusion or MR-DWI DAWN, 2018DEFUSE 3, 2018.
Multiple trials, NNT ~3–5 for LVO
tPA and thrombectomy are NOT mutually exclusive. If LVO suspected → give tPA AND activate thrombectomy team simultaneously. Do not wait for tPA to work before calling interventional.
NIHSS Severity Bands, Drives Antiplatelet Choice
NIHSS
Severity
Antiplatelet Strategy (24h post-tPA / day 1 if no tPA)
ASA 325 mg load → 81 mg. No DAPT, unproven benefit + hemorrhagic conversion risk with large infarct.
Key rule: DAPT is for minor stroke (NIHSS ≤ 3) or high-risk TIA (ABCD² ≥ 4) only. Starting DAPT in moderate-severe stroke does NOT improve outcomes and increases bleeding. Don't reflexively pair ASA + clopidogrel in every stroke admission.
tPA Contraindications
Active internal bleeding or known bleeding diathesis
History of ICH (any time), absolute
Ischemic stroke or head/spine trauma within 3 months
Activate stroke code. ABC. Finger stick glucose (correct if < 60). NIHSS score. Two large-bore IVs. Labs: CBC, BMP, coags, troponin, type & screen.
≤ 20 min -CT
Non-contrast CT head -rule out hemorrhage. CTA head and neck -identify LVO for thrombectomy. CT perfusion if 6–24h window.
≤ 45 min -tPA
If eligible: alteplase 0.9 mg/kg IV (max 90 mg) or tenecteplase 0.25 mg/kg bolus. Door-to-needle target < 60 min. Lower BP to < 185/110 before tPA (labetalol 10–20 mg IV or nicardipine drip).
Thrombectomy
If LVO on CTA → activate interventional neuroradiology. Do not delay tPA for thrombectomy. Give tPA, then go to angio suite. Door-to-puncture target < 90 min.
BP Targets
Scenario
Target
Agents
Pre-tPA
< 185/110
Labetalol 10–20 mg IV, nicardipine 5–15 mg/hr
Post-tPA (24h)
< 180/105
Same agents. Avoid antiplatelets/anticoagulants × 24h.
No tPA given, not for thrombectomy
Permissive HTN < 220/120
Only treat if > 220/120, end-organ damage, or aortic dissection.
Post-thrombectomy
< 140/90 (some use < 160/90)
Tighter control to prevent reperfusion hemorrhage.
Permissive hypertension in stroke maintains perfusion through collaterals. Dropping BP too aggressively in the penumbra zone worsens ischemia. Only lower BP if giving tPA, > 220/120, or specific indications.
Post-thrombectomy BP update: Recent trials (BP-TARGET, 2021, ENCHANTED2/MT, 2022) show intensive BP control < 130 after successful thrombectomy may be HARMFUL. Trend is now toward individualized moderate control (≤ 180/105), not aggressive lowering.
Post-tPA Management (First 24h)
ICU or stroke unit admission
Neuro checks q15 min × 2h → q30 min × 6h → q1h × 16h, catches hemorrhagic conversion early
BP monitoring on same schedule; keep < 180/105
NO antiplatelets, NO anticoagulants × 24h
Avoid central line, arterial line, bladder catheter, NGT × 24h unless essential, bleeding risk at puncture sites
NPO until dysphagia screen passes (formal SLP eval if concerning)
Head of bed: flat if tolerated early (perfusion); 30° if aspiration risk
Repeat CT head at 24h before starting antiplatelets/anticoagulants, rule out asymptomatic hemorrhagic conversion
Dysphagia screen (bedside water swallow) before any PO. Failed → NPO, SLP consult, NGT for meds
Symptomatic ICH After tPA, Reversal
Any acute neuro decline, new HA, vomiting, or BP spike post-tPA = hemorrhagic conversion until proven otherwise. Stop tPA infusion, stat CT head.
Stop tPA infusion immediately
Cryoprecipitate 10 units IV (target fibrinogen > 150–200 mg/dL), the primary reversal agent. NOT FFP (too slow)
Tranexamic acid (TXA) 1 g IV over 10 min as antifibrinolytic adjunct
Platelets if plt < 100K
Aggressive BP control, target SBP < 140 with nicardipine drip INTERACT2, 2013
Stat neurosurgery consult, possible hemicraniectomy (massive MCA + midline shift < 48h, age < 60) or posterior fossa decompression
📋 Clinical Example, Acute Ischemic Stroke: tPA + Thrombectomy Decision
Patient: 72M with a-fib (not on anticoagulation), last known well 2 hours ago, found with right-sided weakness and aphasia. NIHSS 14. BP 196/104, glucose 112, INR 1.1, plts 240K.
10–20 min: Non-con CT, no hemorrhage. CTA, left M1 occlusion. CT perfusion, ischemic core 18 mL, penumbra 72 mL (large mismatch).
20–30 min: BP 196/104 → labetalol 20 mg IV, then nicardipine drip → BP 178/94 (below 185/110 threshold).
30–45 min:Alteplase 0.9 mg/kg IV (weight 80 kg → 72 mg; 7.2 mg bolus, 64.8 mg over 60 min). Simultaneously activate thrombectomy team.
45–90 min: To angio suite during tPA infusion. Mechanical thrombectomy → TICI 2b recanalization at 75 min from door.
Post: NICU admission. Neuro checks q15 min × 2h. BP < 180/105. No antiplatelets × 24h. Repeat CT at 24h → no hemorrhagic conversion → start ASA 325 mg load. NIHSS was 14 (> 3) → NO DAPT, ASA alone. Plan: apixaban 5 mg BID starting day 6 for AF secondary prevention.
Teaching point: tPA is a bridge to thrombectomy, give both when LVO is present. Never delay tPA for CTA. Post-stroke antiplatelet choice is driven by NIHSS: DAPT only for NIHSS ≤ 3.
📋 On Rounds
Pimp Questions
What extended the thrombectomy window from 6h to 24h?
DAWN, 2018 and DEFUSE 3, 2018. Both showed that patients with clinical-imaging mismatch (large clinical deficit but small infarct core on perfusion imaging) benefit from thrombectomy up to 24h. DAWN used clinical-core mismatch; DEFUSE 3 used perfusion-core mismatch. The key concept: it's not about time -it's about salvageable penumbra.
Why check glucose before tPA?
Hypoglycemia is a stroke mimic -it can cause focal neurological deficits identical to stroke (hemiparesis, aphasia, altered consciousness). Giving tPA to a hypoglycemic patient exposes them to major bleeding risk for no benefit. A finger stick glucose takes 10 seconds and is the fastest way to rule out this mimic. Correct glucose < 60, then reassess symptoms before proceeding.
What is the extended window for thrombectomy and what imaging do you need?
Standard tPA window: 0-4.5 hours. Thrombectomy for LVO: up to 24 hours with favorable imaging. DAWN, 2018: 6-24h window if clinical deficit is disproportionate to infarct size on perfusion imaging ("mismatch"). DEFUSE-3, 2018: 6-16h window with perfusion mismatch. Imaging required for extended window: CTA (confirms LVO -M1 MCA, ICA, basilar) + CT perfusion or MRI DWI/perfusion (shows salvageable tissue = penumbra).
What are the absolute contraindications to IV tPA?
Absolute contraindications (within 4.5h window): (1) Active internal bleeding or bleeding diathesis, (2) History of ICH (any time), (3) Ischemic stroke or head/spine trauma within 3 months, (4) Intracranial neoplasm, AVM, or aneurysm, (5) Platelets < 100K / INR > 1.7 / aPTT elevated / DOAC within 48h, (6) SBP > 185 or DBP > 110 not controlled despite treatment, (7) Recent major surgery within 14 days or intracranial/spinal surgery within 3 months, (8) GI/GU bleed within 21 days, (9) Arterial puncture at non-compressible site within 7 days, (10) Suspected infective endocarditis or aortic dissection. Glucose < 50 must be corrected first (stroke mimic).
Does every stroke patient get aspirin + clopidogrel?
No, NIHSS drives the choice. Dual antiplatelet (ASA + clopidogrel × 21 days) is only indicated for minor stroke (NIHSS ≤ 3) or high-risk TIA (ABCD² ≥ 4), started within 24h CHANCE, 2013POINT, 2018. For moderate-severe stroke (NIHSS ≥ 6) or LVO, DAPT increases bleeding without benefit, give ASA alone. THALES, 2020 added ticagrelor + ASA × 30d as alternative for NIHSS ≤ 5 non-cardioembolic. Don't reflexively pair ASA + clopidogrel in every stroke admission.
Tenecteplase or alteplase, which is better?
Non-inferior, and tenecteplase is winning on workflow.AcT, 2022 showed tenecteplase 0.25 mg/kg IV single bolus non-inferior to alteplase 0.9 mg/kg infusion for functional outcome, with similar sICH rates. Tenecteplase advantages: single 5-second push (vs 1-hour infusion), easier transfer to thrombectomy suite, saves ~5 min door-to-needle, same cost. Many stroke centers have switched tenecteplase-first. AHA/ASA lists both as acceptable.
Why permissive hypertension in acute stroke?
The penumbra (viable but ischemic brain around the core infarct) survives on collateral flow, which is passive and pressure-dependent. Dropping BP collapses collaterals → penumbra converts to infarct → worse outcome. AHA guideline: don't treat BP unless > 220/120 in ischemic stroke without tPA. Exceptions: tPA given (must be < 185/110 → < 180/105), aortic dissection, active MI, HF, hypertensive encephalopathy.
Patient on apixaban had last dose 36h ago, can they get tPA?
No, DOACs within 48h are a contraindication to tPA unless an anti-Xa level is undetectable (often unavailable in real time). Alternative: mechanical thrombectomy if LVO is present (tPA contraindications don't preclude thrombectomy). Andexanet alfa reverses apixaban/rivaroxaban but prolongs stroke code timeline too much to be practical as pre-tPA bridge. Stick to thrombectomy in DOAC patients with LVO.
Clinical Examples
📋 Case 1, Large Vessel Occlusion within tPA Window
Patient: 73F with Afib (not on anticoagulation), found by husband with left-sided weakness and slurred speech. Last known well 2 hours ago.
Key findings: BP 178/96, HR 88 (irregular), NIHSS 18 (R gaze preference, left hemiplegia, left hemineglect, dysarthria). CT head: no hemorrhage. CTA: right MCA M1 occlusion. CT perfusion: large penumbra with small core (< 30 mL).
Management:
IV alteplase 0.9 mg/kg (10% bolus, 90% over 60 min). Door-to-needle target ≤ 60 min NINDS, 1995
BP must be < 185/110 BEFORE tPA. Use IV labetalol or nicardipine drip. After tPA: maintain < 180/105 x 24h
Thrombectomy: LVO + NIHSS ≥ 6 + small core = candidate up to 24h DAWN, 2018
tPA is a bridge to thrombectomy. Do NOT delay tPA for CTA
Teaching point: tPA is a bridge, not a destination. If LVO is identified, proceed to thrombectomy regardless of tPA response. Never delay tPA to obtain CTA.
📋 Case 2, Minor Stroke, DAPT Candidate
Patient: 62M with HTN, presents with 30 min of mild right facial droop and word-finding difficulty. Symptoms now resolved. NIHSS 1 (mild dysarthria only). LKW 90 min ago. BP 158/92. Glucose 104.
Key findings: CT head: no hemorrhage. CTA: 60% left MCA stenosis, no occlusion. MRI DWI: punctate left M2 infarct. Within tPA window but NIHSS = 1 → marginal tPA benefit vs bleeding risk. Rapid resolution suggests TIA-like physiology.
Management:
Hold tPA, mild deficit with rapid improvement, low NIHSS = discuss with attending; marginal benefit vs real bleeding risk
BP goal: add lisinopril, target < 130/80 long-term
Etiology workup: carotid Doppler, echo, AF monitoring (Holter or Reveal LINQ if cryptogenic)
Teaching point: Minor stroke / high-risk TIA is the DAPT niche. NIHSS ≤ 3 within 24h → ASA + clopidogrel × 21 days. This is CHANCE, 2013 / POINT, 2018 territory. Don't extend DAPT beyond 21 days (bleeding rises).
📋 Case 3, Wake-Up Stroke with Unknown Onset
Patient: 65M found by wife at 6 AM with right-sided weakness and aphasia. Was normal at bedtime (11 PM). Last known well ~7 hours ago.
Key findings:NIHSS 14 (global aphasia, right hemiplegia). CT head: no hemorrhage. MRI DWI: acute left MCA infarct. FLAIR: no corresponding signal change (DWI-FLAIR mismatch = stroke likely < 4.5h). CTA: left M1 occlusion.
Management:
DWI-FLAIR mismatch suggests onset < 4.5h despite unknown last known well WAKE-UP Trial, 2018
IV alteplase can be given based on WAKE-UP trial criteria (DWI positive, FLAIR negative)
LVO with favorable perfusion: eligible for thrombectomy up to 24h (DAWN/DEFUSE-3 criteria)
If MRI not rapidly available, CT perfusion can identify salvageable penumbra
Teaching point: Wake-up strokes are no longer excluded from thrombolysis. DWI-FLAIR mismatch on MRI can extend the treatment window. Perfusion imaging selects patients based on tissue status, not time alone.
📋 Case 4, Hemorrhagic Conversion After tPA
Patient: 70M received tPA 4 hours ago for acute ischemic stroke (NIHSS 12). Nurse calls: new vomiting, declining consciousness (GCS 14 to 9), new hypertension 210/115.
Key findings:GCS 9, left pupil dilating, right hemiplegia worsening. Consistent with symptomatic intracerebral hemorrhage (sICH) -- most feared tPA complication (~6% incidence).
Management:
Stop tPA infusion immediately. Stat CT head without contrast
Reversal: cryoprecipitate 10 units IV (target fibrinogen > 200 mg/dL). Tranexamic acid 1g IV as adjunct
Aggressive BP control: target SBP < 140 with nicardipine drip INTERACT2, 2013
Stat neurosurgery consult for possible EVD or hemicraniectomy. Reverse coagulopathy before any procedure
Teaching point: Any neurological decline after tPA = hemorrhagic conversion until proven otherwise. Stop tPA, get immediate CT, and give cryoprecipitate (NOT FFP -- too slow). Fibrinogen is the critical target in tPA-related ICH.
📣 Sample Presentation
One-Liner
"Mrs. Taylor is a 73-year-old with Afib (not on anticoagulation) presenting with acute left-sided weakness and aphasia, NIHSS 18, last known well 2 hours ago. CT head negative for hemorrhage. CTA shows right MCA M1 occlusion."
Key Points to Cover on Rounds
Acute ischemic stroke, right MCA LVO, NIHSS 18. CT negative for hemorrhage. Alteplase 0.9 mg/kg administered at 2.5h. Thrombectomy team activated → TICI 2b recanalization. Post-procedure NIHSS 8 (improving). BP target < 180/105 × 24h post-tPA. Repeat CT at 24h: no hemorrhagic conversion. Antiplatelet: ASA 325 mg load → 81 mg (NIHSS 18 → no DAPT per CHANCE/POINT, which require NIHSS ≤ 3). Dysphagia screen: failed → NPO, NGT. Etiology: AF, never anticoagulated. Plan: apixaban 5 mg BID starting day 6 (moderate infarct per 1-3-6-12 rule). Atorvastatin 80 mg. PT/OT/SLP. Secondary prevention (BP < 130/80, lipids, AF).
Monitoring (Post-tPA / Post-Thrombectomy)
Parameter
Frequency
Target / Action
Neuro checks (NIHSS-guided)
q15 min × 2h → q30 min × 6h → q1h × 16h (then q4h × 24h)
Any decline = stat CT to rule out hemorrhagic conversion
Blood pressure
Same schedule as neuro checks × 24h
< 180/105 post-tPA. < 185/110 pre-tPA. Treat with labetalol or nicardipine.
Fingerstick glucose
q1–4h initially
Target 140–180 mg/dL. Avoid hypoglycemia (mimic) and severe hyperglycemia (worsens infarct).
Medical history: AF, HTN, DM, HLD, CAD, PFO, hypercoagulable states, pregnancy, recent illness (endocarditis risk)
Red flags: Thunderclap HA (SAH), neck pain after trauma (dissection), cocaine/sympathomimetic use, recent febrile illness (endocarditis)
NIHSS, Score Every Patient
NIHSS drives thrombectomy eligibility (≥ 6), antiplatelet choice (≤ 3 = DAPT), prognosis, and transfer decisions. Score BEFORE tPA, after tPA, and daily. 11 items, 0–42 scale. → Open interactive NIHSS calculator
NIHSS underscores posterior circulation strokes. A basilar occlusion may score 2–4 despite catastrophic disease. Don't let a low NIHSS talk you out of thrombectomy for a vertebrobasilar LVO, use clinical judgment + CTA.
Imaging (Target ≤ 20 min)
Study
Purpose
Key Findings
Non-contrast CT head FIRST
Rule out hemorrhage, tPA contraindicated if ICH
Early ischemic changes (loss of gray-white differentiation, insular ribbon sign, hyperdense MCA sign). ASPECTS score < 6 = large core → poor thrombectomy candidate.
CTA head & neck ESSENTIAL FOR LVO
Identify LVO (ICA, M1, M1-equivalent, basilar) for thrombectomy triage
Clot visualization. Collateral scoring. Carotid stenosis / dissection. Tandem occlusions. Do NOT delay tPA waiting for CTA.
DAPT increases bleeding without proven benefit in moderate-severe stroke. Large infarct core + DAPT = hemorrhagic conversion risk.
Clopidogrel CYP2C19 non-responders (~30% of East Asians, ~15% of others): consider ticagrelor instead. Genotyping is done at some stroke centers after DAPT failure.
Statin
Drug
Dose
Notes
Atorvastatin HIGH INTENSITY
80 mg PO daily
Start on admission. SPARCL, 2006. LDL goal < 70 mg/dL.
Rosuvastatin HIGH INTENSITY
20–40 mg PO daily
Alternative if atorvastatin intolerance. In Asian patients lower doses may suffice.
Anticoagulation (Cardioembolic Stroke, AF)
Timing rule of thumb ("1-3-6-12 day rule"): start DOAC based on infarct size, TIA (day 1), small stroke (day 3), moderate (day 6), large (day 12). ELAN, 2023 supports earlier start than the traditional rule.
Drug
Dose
When to Start (post-stroke)
Apixaban (Eliquis) PREFERRED
5 mg BID (2.5 mg BID if ≥ 2 of: age ≥ 80, weight ≤ 60 kg, Cr ≥ 1.5)
Typical: day 1–3 for small, day 6–12 for large infarct. ELAN 2023 supports earlier.
Rivaroxaban
20 mg daily (15 mg if CrCl 15–50)
Take with food for bioavailability.
Dabigatran
150 mg BID (110 mg BID if high bleed risk)
Avoid CrCl < 30. Idarucizumab for reversal.
Edoxaban
60 mg daily (30 mg if CrCl 15–50 or weight ≤ 60 kg)
Avoid if CrCl > 95 (reduced efficacy).
Warfarin
Goal INR 2–3
Use if mechanical valve, significant mitral stenosis, antiphospholipid syndrome. Bridge with heparin if INR < 2.
Adjuncts & Supportive
Glucose control: target 140–180 mg/dL. Avoid hypoglycemia (mimic) and severe hyperglycemia (worsens infarct).
DVT prophylaxis: mechanical compression from admission. Enoxaparin 40 mg SC daily after 24h post-tPA (if no ICH on repeat scan). Avoid heparin gtt in cardioembolic stroke, increases hemorrhagic conversion.
Orolingual angioedema on tPA: stop infusion, IV methylprednisolone 125 mg + diphenhydramine 50 mg + famotidine 20 mg. Epinephrine if airway compromise. Higher risk in ACEi users.
⚡ Summary
Summary
Time Is Brain
Roughly 1.9 million neurons are lost per minute of ischemia.Target door-to-needle under 60 minutes and door-to-CT under 20.Establish the last known well time, not the time symptoms were noticed: everything downstream depends on that single piece of history, and it usually comes from a family member or EMS rather than the patient.
Know the Two Windows
Thrombolysis: within 4.5 hours of last known well.Thrombectomy: within 6 hours for a large vessel occlusion, extended to 24 hours with favorable perfusion imaging (DAWN, DEFUSE 3). Wake-up strokes may still qualify using MRI diffusion-FLAIR mismatch, so an unwitnessed onset is not automatically excluded.
Non-Contrast CT First, to Exclude Hemorrhage
Its job is to rule out bleeding, not to confirm infarction, which is often invisible in the first hours. Then CT angiography for large vessel occlusion, and perfusion imaging for the extended thrombectomy window.Check a glucose immediately, since hypoglycemia is the great stroke mimic and is instantly correctable.
Get the Blood Pressure Rules the Right Way Round
If giving thrombolysis: below 185/110 before, and below 180/105 for 24 hours after.If not giving thrombolysis: permissive hypertension, treating only above 220/120, because the ischemic penumbra depends on collateral perfusion and lowering the pressure extends the infarct. These two targets are opposite, and confusing them causes harm in both directions.
Antiplatelet Choice Depends on the NIHSS
Minor stroke with NIHSS 3 or below, or high-risk TIA with ABCD2 4 or above: dual antiplatelet with aspirin plus clopidogrel for 21 days, then single agent (CHANCE, POINT). Larger strokes: single antiplatelet, because prolonged dual therapy increases hemorrhage without benefit. Start aspirin at 24 to 48 h, and wait 24 h after thrombolysis.
Manage the First 24 Hours After Thrombolysis Deliberately
No antiplatelets or anticoagulants for 24 hours, no central lines or arterial punctures at non-compressible sites, and frequent neurologic checks.Any sudden deterioration, headache, vomiting or a rise in blood pressure means stop the infusion and get an urgent CT, and treat symptomatic hemorrhage with cryoprecipitate and tranexamic acid.
Do Not Reflexively Anticoagulate Atrial Fibrillation Early
Timing depends on infarct size and hemorrhagic risk, commonly 3 to 14 days out, because early anticoagulation of a large infarct causes hemorrhagic transformation. Treat fever, glucose and hypoxia, all of which worsen outcome, and screen swallowing before anything goes by mouth, since aspiration pneumonia is a leading complication.
Finish the Workup and the Secondary Prevention
Vessel imaging, echocardiography, prolonged rhythm monitoring for occult atrial fibrillation, lipids and A1c.High-intensity statin, blood pressure control, antithrombotic matched to the mechanism, and carotid revascularization for symptomatic stenosis of 70% or more, ideally within 2 weeks. Add early rehabilitation and mobilization, which independently improve functional outcome.
Sudden interruption of blood flow to the intestines. "Pain out of proportion to exam" is the classic teaching. Mortality 60–80% if not caught early. Think it, CT it, call surgery.
Monitoring
Serial abdominal exams q2-4h
Lactate q4-6h
UOP
Repeat CTA if change
🔍 Overview
Types
Type
% of AMI
Mechanism
Key Clue
Arterial embolism (SMA) (~50%)
Most common
Embolus from heart (Afib, LV thrombus, valvular) lodges in SMA
Sudden onset severe pain. Afib is the #1 risk factor. Pain out of proportion to exam.
Arterial thrombosis (~25%)
Thrombosis at atherosclerotic plaque (usually SMA origin)
History of chronic mesenteric ischemia (postprandial pain, food fear, weight loss) → acute event.
ICU patients on vasopressors, post-cardiac surgery, hemodialysis, shock. No clot -vasospasm.
Presentation
"Pain out of proportion to exam" -severe abdominal pain with a soft, non-tender abdomen (early). The exam catches up later (peritonitis = bowel already dead).
By the time peritoneal signs develop, bowel is already necrotic. The window between "pain out of proportion" and dead bowel is hours. Have a low threshold for CT angiography in any patient with acute severe abdominal pain + Afib or risk factors.
Elevated (often > 4). But normal lactate does not exclude early AMI. Trend is more useful than single value.
Plain X-ray
Late findings: pneumatosis intestinalis, portal venous gas, free air (perforation). Normal X-ray does not rule out AMI.
RoundsRx Licensed Content - Unauthorized Use Prohibited🚨 Management
Acute Management
Immediate
Aggressive fluid resuscitation (third-spacing is massive). Broad-spectrum antibiotics (piperacillin-tazobactam or meropenem -cover gut flora including anaerobes). Anticoagulation with heparin dripAcosta, 2014 (prevent clot propagation). NPO. NG tube if distended/vomiting.
Surgical consult
IMMEDIATE surgical consult -do not wait. If peritonitis, frank necrosis, or perforation → emergent laparotomy with resection of dead bowel. Second-look laparotomy at 24–48h is standard. Bala, 2017
Endovascular
If no peritonitis and arterial occlusion → consider catheter-directed thrombolysis or aspiration thrombectomy (interventional radiology). Most effective for SMA embolism without necrosis.
NOMI
Treat the underlying low-flow state. Optimize cardiac output, wean vasopressors if possible. Intra-arterial papaverine (vasodilator) into SMA via angiography. Avoid vasoconstrictors (pressors worsen splanchnic ischemia).
Mortality is determined by time to intervention. Pre-necrosis intervention → 30% mortality. Post-necrosis → 60–80%. The clinical window between "pain out of proportion" and dead bowel is hours. Have a very low threshold for CTA in any acute severe abdominal pain with a-fib, recent MI, CHF, PVD, or hypercoagulable state.
🧪 Workup
Workup
CTA abdomen/pelvis -sensitivity >95%
Lactate -LATE marker
CBC -leukocytosis
BMP -acidosis, AKI
💊 Medications
Medications
Drug
Dose
Route
Notes
Heparin
80U/kg→18U/kg/hr
IV
All types
Pip-tazo
4.5g q6h
IV
If peritonitis
IVF aggressive
NS/LR
IV
Third-spacing
Papaverine
30-60mg/hr IA
IA
NOMI only
📋 On Rounds
Pimp Questions
Why is "pain out of proportion to exam" the classic finding?
In early mesenteric ischemia, the visceral peritoneum is ischemic (causes severe, poorly localized pain) but the parietal peritoneum is not yet involved (no rebound/guarding). The pain is visceral -deep, severe, colicky -but the abdomen is soft and non-tender on exam. Once the bowel becomes necrotic and transmural inflammation reaches the parietal peritoneum → peritoneal signs appear.
What is the most common cause of acute mesenteric ischemia?
SMA embolism (~50%), most commonly from cardiac source (Afib is the #1 risk factor, followed by LV thrombus post-MI, valvular disease). The embolus typically lodges 6–8 cm distal to the SMA origin (past the middle colic artery branch point), which is why the proximal jejunum is often spared but mid-gut is affected.
Why is the classic teaching 'pain out of proportion to exam' so important in mesenteric ischemia?
Because by the time peritoneal signs develop, the bowel is dead. Early mesenteric ischemia causes visceral pain (from bowel wall ischemia) but the peritoneum is not yet involved → the abdomen is soft with minimal tenderness on exam. This is the diagnostic window, the patient is screaming in pain but you can barely feel anything on exam. Once peritonitis develops (rigid abdomen, rebound, guarding), the window has closed, transmural necrosis has reached the serosa, meaning bowel is already dead and mortality jumps to 60–80%. Catching it in the "soft abdomen, severe pain, lactate rising, a-fib/risk factors" window is what saves lives, have a very low threshold for urgent CTA.
What are the different types of mesenteric ischemia and how do they differ?
(1) Arterial embolism (50%): sudden onset, Afib is the #1 risk factor. SMA is the most commonly affected vessel. CTA: abrupt cutoff of SMA. Treatment: surgical embolectomy or catheter-directed thrombolysis. (2) Arterial thrombosis (25%): gradual onset ("intestinal angina" -postprandial pain, food fear, weight loss preceding the acute event). CTA: chronically diseased vessel with acute occlusion. Treatment: surgical revascularization.
Clinical Examples
📋 Case 1, Acute SMA Embolism
Patient: 72F with Afib (not on anticoagulation). Sudden severe periumbilical pain × 4h, nausea, bloody diarrhea. HR 110, BP 95/60. Abdomen: diffuse tenderness but soft, no rebound. Lactate 5.2, WBC 19K.
Key findings: Pain out of proportion to exam, classic for early mesenteric ischemia. Afib without anticoagulation = #1 risk for SMA embolism. Elevated lactate confirms tissue ischemia.
Management:
Emergent CT angiography (CTA), expect abrupt SMA cutoff at mid-vessel (emboli lodge at branch points)
IV heparin bolus + drip (prevent clot propagation)
Emergent surgery consult for SMA embolectomy + bowel viability assessment
Broad-spectrum antibiotics (piperacillin-tazobactam), bacterial translocation through ischemic bowel wall
Aggressive IVF resuscitation, third-spacing and lactic acidosis
Teaching point: The golden window for mesenteric ischemia is before peritoneal signs develop. Once the abdomen becomes rigid, bowel necrosis is likely irreversible. A soft abdomen with severe pain = act now.
📋 Case 2, Non-Occlusive Mesenteric Ischemia (NOMI)
Patient: 68M in ICU on norepinephrine 0.3 mcg/kg/min for cardiogenic shock post-MI. Develops abdominal distension, bloody NG output, rising lactate 3.2 → 7.8. WBC 24K.
Key findings: Non-occlusive mesenteric ischemia, splanchnic vasoconstriction from shock + vasopressors. No embolic source. CTA may show patent but narrowed mesenteric vessels with poor bowel wall enhancement.
Management:
Optimize cardiac output (the root cause), inotropes, IABP, reduce vasopressors if possible
CTA to confirm NOMI (patent vessels but poor bowel enhancement) and exclude occlusive disease
If confirmed NOMI: papaverine infusion via SMA catheter (direct splanchnic vasodilator) if available
NPO, NGT decompression, serial abdominal exams q4h
Surgery consult, if peritoneal signs develop, exploratory laparotomy for bowel viability assessment
Teaching point: NOMI accounts for ~20% of mesenteric ischemia and has the highest mortality (60-80%) because the underlying cause (shock) is often difficult to reverse. The treatment is hemodynamic optimization, not anticoagulation or surgery.
📋 Case 3, Chronic Mesenteric Ischemia (Intestinal Angina)
Patient: 65F smoker with PVD. Postprandial epigastric pain × 6 months, occurring 15-30 min after eating, lasting 1-2h. "Food fear", eating less, lost 20 lb. CTA: > 70% stenosis of SMA and celiac artery.
Key findings: Classic chronic mesenteric ischemia triad: postprandial pain + food avoidance + weight loss. Requires ≥ 2 of 3 mesenteric vessels to be stenotic for symptoms (collateral supply compensates for single vessel disease).
Management:
Mesenteric angiography with possible stenting of SMA (first-line for chronic mesenteric ischemia)
Surgical bypass (SMA bypass graft) if endovascular approach fails or not feasible
Nutritional optimization, small frequent meals, supplemental nutrition pre-procedure
Urgent revascularization, risk of acute-on-chronic ischemia (bowel infarction) is 30-50% if untreated
Teaching point: Chronic mesenteric ischemia is the "angina of the gut." The diagnosis is often delayed because postprandial pain has a broad differential. Weight loss + food fear + vascular risk factors should trigger CTA of mesenteric vessels.
📣 Sample Presentation
One-Liner
"Mr. Ahmed is a 78-year-old with Afib on warfarin (subtherapeutic INR 1.4) presenting with severe acute abdominal pain out of proportion to exam. Lactate 6.8. CT angiography shows SMA embolism with jejunal ischemia."
Key Points to Cover on Rounds
Acute mesenteric ischemia -SMA embolism (likely cardiogenic from Afib). Lactate 6.8, WBC 22K. CT angiography: SMA cutoff at mid-vessel. No peritoneal signs yet (early presentation). Surgery emergently consulted -taken to OR for SMA embolectomy + bowel viability assessment. Heparin drip started. Broad-spectrum antibiotics (pip-tazo). Aggressive fluid resuscitation. Plan: OR → SMA embolectomy, possible bowel resection if non-viable, ICU post-op.
Monitoring
Serial abdominal exams q2-4h
Lactate q4-6h
UOP
Repeat CTA if change
⚡ Summary
Summary
Pain Out of Proportion Is the Diagnosis
Severe abdominal pain with an unimpressive examination, in a patient who looks worse than their abdomen.Mortality is 60 to 80% if it is not caught early, and peritonitis appearing means the bowel is already infarcting. Think it, CT it, call surgery.
Know the Four Types, Because They Are Treated Differently
Arterial embolism (about 50%): sudden, in atrial fibrillation or after MI, lodging at the SMA. Arterial thrombosis: on background atherosclerosis, often with preceding postprandial pain and food fear. Non-occlusive: low-flow in shock or on vasopressors, with no clot to remove. Venous thrombosis: younger patients, hypercoagulable states, more insidious, treated with anticoagulation rather than an operation.
CT Angiography Is the Test
Get it early and do not substitute a plain film or an ultrasound.Do not withhold contrast for renal protection: the diagnosis is far more dangerous than the contrast. Look for arterial cutoff, bowel wall thickening or non-enhancement, pneumatosis, portal venous gas and mesenteric edema.
Do Not Rely on Lactate
A normal lactate early does not exclude it. Lactate rises once the bowel is infarcting, which is exactly when the window has closed, so it is a late marker of a lost opportunity rather than a screening test. The same applies to leukocytosis and metabolic acidosis.
Resuscitate and Anticoagulate Immediately
Aggressive fluids, broad-spectrum antibiotics because of bacterial translocation, and systemic heparin unless there is a contraindication.Avoid vasopressors where possible, particularly alpha agonists, since splanchnic vasoconstriction worsens the ischemia; if pressors are unavoidable, favor those with less splanchnic effect and correct volume first.
Match the Intervention to the Type
Embolism: embolectomy, open or endovascular.Thrombosis: revascularization by stenting or bypass.Non-occlusive: correct the low-flow state, and consider an intra-arterial vasodilator such as papaverine.Venous: anticoagulation alone in most cases, with surgery only for peritonitis or infarcted bowel.
Plan the Second Look
A patient with resected bowel goes back to the operating room at 24 to 48 h.Bowel that looked marginal at the first operation declares itself by the second, and leaving necrotic segments in place is a common cause of postoperative deterioration. Damage-control surgery with a temporary closure is appropriate in an unstable patient.
Monitor Closely and Treat the Cause
Serial abdominal examinations every 2 to 4 h, lactate every 4 to 6 h, urine output, and repeat CTA if the picture changes.Then treat the underlying disease: anticoagulate the atrial fibrillation, treat the atherosclerosis, and work up a hypercoagulable state in venous disease. Chronic mesenteric ischemia presents as postprandial pain and weight loss with food avoidance, and it is the warning sign that precedes the acute event.
Fluid in the pleural space. Step 1: transudative or exudative (Light's criteria). Step 2: if exudative, find the cause. Step 3: drain if needed. You will do thoracenteses -know Light's cold.
🔍 Overview
Light's Criteria -Exudate if ANY ONE Met
If any ONE of these three is positive → exudate. All three negative → transudate.
Criterion
Exudate Cutoff
Pleural protein / Serum protein
> 0.5
Pleural LDH / Serum LDH
> 0.6
Pleural LDH
> 2/3 upper limit of normal for serum LDH
Light's criteria misclassify ~25% of transudates as exudates (especially in HF patients on diuretics). If you suspect a transudative effusion misclassified as exudate → check serum-pleural albumin gradient. If > 1.2 g/dL → transudate despite Light's.
Common Causes
Transudative
Exudative
CHF (most common overall)
Pneumonia / parapneumonic (most common exudate)
Hepatic hydrothorax (cirrhosis)
Malignancy (lung, breast, lymphoma)
Nephrotic syndrome
PE
Peritoneal dialysis
TB (lymphocyte-predominant, ADA > 40)
Hypothyroidism
Autoimmune (SLE, RA)
Pancreatitis (elevated amylase)
Esophageal rupture (low pH, high amylase)
Pleural Fluid Analysis -What to Send
Always Send
If Indicated
Cell count with differential
Cytology (if malignancy suspected -send ≥ 60 mL)
Protein, LDH, glucose
ADA (adenosine deaminase) -TB (> 40 suggestive)
Gram stain, culture
Amylase -pancreatitis, esophageal rupture
pH
Triglycerides -chylothorax (> 110 mg/dL)
+ serum protein, LDH, albumin (same day)
Hematocrit -hemothorax (pleural Hct > 50% of blood)
🚨 Management
When to Tap
New effusion of unknown etiology -diagnostic thoracentesis
Clinically significant (dyspnea) -therapeutic thoracentesis (remove up to 1.5 L per session)
Suspected empyema or complicated parapneumonic -emergent drainage
Do NOT tap if: bilateral symmetric effusions in a patient with clear CHF (treat the HF first -they'll resolve). Only tap if unilateral, asymmetric, febrile, or not responding to diuresis.
Chest tube drainage mandatory. If loculated or not draining → tPA/DNase or VATS. Prolonged antibiotics (3–6 weeks).
Malignant Effusion
Positive cytology or biopsy confirms malignancy
Recurrent → indwelling pleural catheter (IPC) or talc pleurodesis
Median survival with malignant effusion: 3–12 months (depends on primary cancer)
IPC allows outpatient drainage, avoids repeated thoracenteses. Can achieve spontaneous pleurodesis in ~50%.
📋 On Rounds
Light's criteria classify a CHF patient's effusion as exudative. What do you do?
Light's criteria misclassify ~25% of transudates as exudates, especially in CHF patients on diuretics (diuresis concentrates pleural protein and LDH, pushing ratios above exudative cutoffs). Check the serum-pleural albumin gradient: if > 1.2 g/dL → the effusion is truly transudative despite meeting Light's criteria.
What pleural fluid pH tells you and when it changes management?
pH < 7.2 in a parapneumonic effusion = complicated → needs chest tube. Low pH means bacteria are metabolizing glucose → producing CO₂ and lactic acid → acidifying the fluid. This also correlates with high LDH and low glucose. In empyema, pH can drop below 7.0. Important: collect pH in a heparinized blood gas syringe, not a regular tube. Also: low pH in a non-infected effusion → think malignancy, esophageal rupture, or rheumatoid pleurisy.
A pleural fluid has protein ratio 0.32, LDH ratio 0.58, and LDH 180 (ULN = 200). Transudate or exudate?
Exudate. Light's criteria require meeting any 1 of 3: (1) Fluid/serum protein ratio > 0.5 (this is 0.32 -NOT met), (2) Fluid/serum LDH ratio > 0.6 (this is 0.58 -NOT met), (3) Fluid LDH > 2/3 of serum ULN (2/3 × 200 = 133; fluid LDH is 180 -MET). One criterion positive = exudate. Common trap: Light's criteria misclassify ~25% of transudates as exudates (especially in diuresed CHF patients -diuretics concentrate the fluid).
How do you manage a complicated parapneumonic effusion vs empyema?
Uncomplicated parapneumonic: fluid is free-flowing, pH > 7.2, glucose > 60, LDH < 1000, gram stain/culture negative. Treatment: antibiotics alone, no chest tube. Complicated parapneumonic: pH < 7.2, glucose < 60, LDH > 1000, or positive gram stain/culture -but no frank pus. Loculations may be present. Treatment: chest tube + antibiotics.
Clinical Examples
📋 Case 1, CHF Effusion Misclassified by Light's Criteria
Patient: 74M, HFrEF (EF 25%), on aggressive diuresis with IV furosemide. Large right-sided pleural effusion tapped for dyspnea relief.
Key findings: Pleural fluid: protein ratio 0.55, LDH ratio 0.52, LDH 160 (ULN 200). Meets 1 of 3 Light's criteria (protein ratio > 0.5) → classified as exudate. But: bilateral LE edema, JVD, BNP 2,800.
Teaching point: Light's criteria misclassify ~25% of CHF transudates as exudates, especially in diuresed patients. The serum-effusion albumin gradient (> 1.2 g/dL = transudate) corrects for this. Always apply clinical context before ordering extensive exudative workup.
📋 Case 2, Complicated Parapneumonic Effusion
Patient: 56F, DM2 and alcohol use disorder, admitted with RLL pneumonia 5 days ago on ceftriaxone + azithromycin. Persistent fever despite antibiotics, worsening dyspnea.
Key findings: CXR: enlarging right-sided effusion with loculations on ultrasound. Thoracentesis: turbid fluid, pH 6.9, glucose 28, LDH 2,800, gram stain: gram-positive cocci in chains. Protein ratio 0.8.
Intrapleural tPA (10 mg) + DNase (5 mg) BID x 3 days for loculated effusion
CT surgery consult for VATS if inadequate drainage after tPA/DNase
Repeat imaging in 24-48h to assess drainage adequacy
Teaching point: Pleural fluid pH is the single most important test for determining if a parapneumonic effusion needs drainage. pH < 7.2 = complicated = chest tube. MIST2, 2011 showed that combination tPA + DNase (not either alone) significantly improved fluid drainage and reduced surgical referral.
📋 Case 3, Malignant Pleural Effusion
Patient: 68F, never-smoker, presents with 3 months of progressive dyspnea and 15-lb weight loss. No fever, no cough. CXR: massive left-sided effusion with contralateral mediastinal shift.
Key findings: Thoracentesis: 2L bloody fluid. Exudate by Light's criteria (protein ratio 0.72, LDH ratio 0.85). Cytology: adenocarcinoma (TTF-1 positive, consistent with lung primary). Glucose 42, pH 7.18.
Management:
Symptomatic improvement with large-volume thoracentesis (limit to 1.5L per session to avoid re-expansion pulmonary edema)
Low pH + low glucose in malignant effusion = high tumor burden, poor prognosis
For recurrent effusion: tunneled pleural catheter (PleurX) preferred over pleurodesis for most patients
Oncology referral for staging and driver mutation testing (EGFR, ALK, ROS1)
Goals of care discussion given advanced malignancy
Teaching point: Malignant effusions are exudative and often bloody. Low glucose and low pH in a malignant effusion predict poor survival and failed pleurodesis. Tunneled pleural catheters allow outpatient drainage and achieve spontaneous pleurodesis in ~45% of patients. Lung and breast cancer are the most common causes.
📣 Sample Presentation
One-Liner
"Mr. Hernandez is a 68-year-old with CHF presenting with worsening dyspnea. CXR shows large left-sided pleural effusion. Thoracentesis: protein ratio 0.28, LDH ratio 0.32. Transudative by Light's criteria."
Key Points to Cover on Rounds
Large left pleural effusion -transudative (protein ratio 0.28, LDH ratio 0.32, LDH 108 -all below Light's cutoffs). Etiology: CHF (bilateral LE edema, elevated BNP 1,800, known HFrEF). 1.5L drained with symptomatic improvement. Fluid: clear, straw-colored. Cell count and cytology sent (expected benign). No further invasive workup needed for transudative effusion with clear etiology. Treatment: diuresis optimization (furosemide uptitrated). Plan: if recurrent despite optimal diuresis → consider tunneled pleural catheter. Not empyema, not malignant based on presentation.
🧪 Workup
Workup
See the Overview and Management tabs for the pleural effusion workup algorithm (CXR → thoracic ultrasound → diagnostic thoracentesis with Light's criteria, pleural fluid studies, and pleural biopsy when malignancy or TB is suspected).
💊 Medications
Medications
Medication details (antibiotics for parapneumonic/empyema, intrapleural tPA + DNase for loculated empyema per MIST-2, pleurodesis agents for malignant effusion) are in the Management tab with evidence-based dosing and trial citations.
⚡ Summary
Summary
Light's Criteria: Any One Means Exudate
Pleural-to-serum protein ratio above 0.5, pleural-to-serum LDH ratio above 0.6, or pleural LDH above two-thirds the upper limit of normal serum LDH.All three negative means transudate.The criteria are highly sensitive for exudates and therefore misclassify some transudates as exudates, particularly after diuresis.
Check the Albumin Gradient When Diuretics Are On Board
A diuresed heart failure patient concentrates pleural protein and can be misclassified as exudative.A serum-to-pleural albumin gradient above 1.2 g/dL indicates a transudate regardless of Light's criteria, and it rescues these patients from an unnecessary exudate workup.
The Two Categories Have Different Differentials
Transudate: heart failure (by far the commonest), cirrhosis, nephrotic syndrome, and it means the pleura itself is normal and the problem is hydrostatic or oncotic.Exudate: parapneumonic effusion, malignancy, pulmonary embolism, tuberculosis, and connective tissue disease, meaning the pleura is inflamed or leaking.
Send the Right Studies
Protein, LDH, pH, glucose, cell count with differential, Gram stain and culture, and cytology if malignancy is possible.Add adenosine deaminase for suspected tuberculosis, triglycerides for chylothorax, and amylase for pancreatic or esophageal causes.pH must be collected anaerobically in a blood gas syringe and run promptly, or it is meaningless.
pH Decides Whether the Tube Goes In
A parapneumonic effusion with pH below 7.20, glucose below 60 mg/dL, a positive Gram stain or culture, or frank pus is a complicated effusion or empyema and needs chest tube drainage.Antibiotics alone do not clear an infected pleural space, and a delayed tube leads to loculation and a decortication.
Break Loculations Rather Than Escalating Antibiotics
Intrapleural tPA plus DNase improves drainage and reduces the need for surgery in loculated pleural infection (MIST2). Neither agent alone works.Refer for VATS decortication when drainage fails, and do not simply keep the tube in place on suction hoping it will resolve.
Malignant Effusions Recur
Cytology is positive in only about 60% on a first tap, so a negative result does not exclude malignancy: repeat it or proceed to pleural biopsy. Because they recur, definitive management is pleurodesis or an indwelling pleural catheter rather than repeated therapeutic taps.
Drain Slowly
Remove no more than about 1.5 liters at one sitting, and stop for chest pain, cough or a fall in pleural pressure.Rapid or large-volume drainage causes re-expansion pulmonary edema, particularly when the lung has been collapsed for a long time. Use ultrasound guidance, which reduces pneumothorax and dry taps substantially.
RoundsRx Infographic Series · #98 · Respiratory · PDF 148 KB
Text version
Pulmonology · One Pager
Pleural Effusion
Thoracentesis → Light's criteria → transudate (treat cause) or exudate (further workup). Parapneumonic: pH/glucose/LDH determine if chest tube needed.
🧪 Light's Criteria
Exudate if ANY 1: protein ratio > 0.5, LDH ratio > 0.6, fluid LDH > 2/3 serum ULN. Sensitive but 25% false-positive for transudates (diuresed CHF). Check albumin gradient if discordant.
The most common reason for hospital admission. CAP vs HAP vs VAP -the classification drives empiric antibiotics. Risk-stratify with CURB-65 or PSI to determine inpatient vs outpatient. Get cultures before antibiotics in the right patients.
🔍 Overview
Classification
Type
Definition
Common Organisms
Empiric Antibiotics
CAP (Community-acquired)
Acquired outside hospital, or < 48h after admission
S. pneumoniae (#1), H. influenzae, Mycoplasma, Chlamydophila, Legionella, respiratory viruses
Outpatient (healthy): Amoxicillin 1g TID Outpatient (comorbid): Amox-clav + azithromycin Inpatient: Ceftriaxone IV + azithromycin IV ICU: Same ± vanc/linezolid if MRSA risk (linezolid if severe)
HAP* (Hospital-acquired) *HAP = Hospital-Acquired Pneumonia (≥48h after admission)
≥ 48h after admission, not intubated at time of infection
Pip-tazo 4.5g q6h or cefepime 2g q8h + vancomycin or linezolid (MRSA; linezolid if severe) Meropenem if ESBL/MDR risk Pip-tazo if anaerobic concern (aspiration + abscess/empyema). Cefepime if no anaerobes -especially with vanc (↓ AKI) ACORN, 2023
VAP* (Ventilator-associated) *VAP = Ventilator-Associated Pneumonia (≥48h after intubation)
≥ 48h after intubation
Same as HAP + higher Pseudomonas and MDR organisms
Pip-tazo or cefepime or meropenem + vanc or linezolid (MRSA; linezolid if severe) ± double Pseudomonas coverage if MDR risk Pip-tazo if anaerobic risk (aspiration, abscess). Cefepime + vanc preferred (lower nephrotoxicity). Need cefepime + anaerobes → add metronidazole
Aspiration pneumonia
Witnessed or high-risk aspiration event (AMS, dysphagia, GERD). Classically RLL or posterior segments of upper lobes (gravity-dependent).
Same as CAP -S. pneumoniae, H. influenzae, S. aureus, Enterobacteriaceae. Anaerobes are NOT the primary cause (old teaching). Anaerobes only significant if: lung abscess, empyema, necrotizing PNA, or poor dentition + indolent course.
Acute: Treat like CAP (ceftriaxone + azithro) If abscess/empyema/necrotizing: ADD anaerobic coverage -amp-sulbactam 3g q6h or pip-tazo or metronidazole Chemical pneumonitis = NO abx
⚠️ HCAP is no longer a recognized category (ATS/IDSA 2016 eliminated it). Old teaching: Hospitalization within 90 days, nursing home residence, hemodialysis, or home wound care = "Healthcare-Associated Pneumonia" → treat like HAP with broad-spectrum antibiotics. Current teaching: HCAP led to massive over-treatment, most of these patients had CAP organisms, not MDR bugs. Increased C. diff and worse outcomes. Now: classify as CAP and assess individual MDR risk factors (prior MRSA culture, prior Pseudomonas culture, IV antibiotics within 90 days, structural lung disease) to decide if broader coverage is needed.
Severity Scores & Severe CAP Definitions
Different scores answer different questions. The default "severe CAP" definition residents are expected to know is IDSA/ATS 2019 (1 major OR ≥ 3 minor). CURB-65 and PSI are separate severity scores used alongside it. Click any heading below to expand.
IDSA / ATS 2019 criteriaSTANDARD Use to decide: ICU admission. 1 major OR ≥ 3 minor = severe CAP.
Used for the ICU admission decision. 1 major OR ≥ 3 minor criteria = severe CAP.
ICU admission and closer monitoring for shock and respiratory failure.
Standard empiric regimen still: ceftriaxone + macrolide (or respiratory fluoroquinolone). Severity alone does not change the antibiotics.
MRSA and Pseudomonas coverage are NOT added automatically. Add only if individual risk factors are present: prior respiratory isolation of that organism, hospitalization + IV antibiotics in the past 90 days, structural lung disease (bronchiectasis, severe COPD), or locally validated high prevalence. MRSA nasal PCR (~95% NPV) helps you stop empiric vanc/linezolid early.
Earlier consideration of adjunctive hydrocortisone (CAPE COD 2023). See the CAPE COD criteria collapsible below for steroid eligibility.
CURB-65 Use to decide: outpatient vs inpatient vs ICU at the front door. Score 0-1 home, 2 admit, 3-5 consider ICU.
Used to decide outpatient vs inpatient vs ICU at the front door. Not a strict "severe vs not" binary.
Letter
Criterion
C
Confusion (new AMS)
U
Urea (BUN) > 19 mg/dL (or > 7 mmol/L)
R
Respiratory rate ≥ 30
B
BP: SBP < 90 OR DBP ≤ 60
65
Age ≥ 65
Score
Disposition
30-day mortality
0-1
Outpatient (consider home Rx)
< 3%
2
Inpatient ward
~9%
3-5
ICU consideration
15-40%
Open CURB-65 calculator →
PSI / Pneumonia Severity Index Use to decide: granular severity (Class I-V). More variables and better discrimination than CURB-65 but harder to calculate at bedside. PSI > 130 = CAPE COD steroid threshold.
Calculator-based, factors in age, comorbidities, exam findings, and labs. Stratifies into Class I-V. Class I-II outpatient, Class III observation, Class IV-V inpatient or ICU. PSI > 130 is the cutoff used by CAPE COD, 2023 for severe CAP eligible for hydrocortisone. PSI is more granular than CURB-65 (more variables, better discrimination) but harder to calculate at bedside without a calculator.
CAPE COD criteria Use to decide: should I add hydrocortisone? Any one of: intubated, HFNC FiO2 ≥ 0.5 with P/F < 300, NIV with P/F < 300, or PSI > 130.
Used specifically when asking "should I add hydrocortisone?" Any ONE of the following triggers severe-CAP status for the steroid indication:
Intubated / mechanical ventilation
HFNC at FiO2 ≥ 0.5 with PaO2 / FiO2 < 300
Non-invasive ventilation with PaO2 / FiO2 < 300
PSI > 130
Overlaps with IDSA "severe" but operationalized slightly differently, focused on respiratory severity that inflammation modulation can help with. See When to Add Steroids in Pneumonia → for the full regimen.
💊 Treatment
📋 What changed in the 2025 ATS update (published Jan 2026, updates ATS/IDSA 2019 on four questions; empiric regimens, severity criteria and the workup are UNCHANGED)
Duration got shorter, not longerCHANGED -in the clinically stable patient, under 5 days with a 3-day minimum is now preferred for outpatients and non-severe inpatients. 2019 set the floor at 5 days. Severe CAP still gets ≥ 5 days, and that one is a strong recommendation.
Steroids flipped in severe CAPCHANGED -now a conditional recommendation FOR systemic steroids in severe CAP, where 2019 suggested against them. In non-severe CAP the recommendation against is now strong (it was conditional).
A detected respiratory virus can mean no antibiotics at allNEW 2025 -a healthy outpatient with no comorbidity and a positive viral PCR does not need antibiotics. Outpatients with comorbidities, and all hospitalized patients, still do.
Lung ultrasound is an acceptable alternative to chest radiographyNEW 2025 -where the expertise and a standardized protocol exist. 2019 did not address it.
Empiric Antibiotics
Setting
Regimen
Notes
CAP -Outpatient, no comorbidities
Amoxicillin (Amoxil) 1g TID 1ST LINE
Or doxycycline 100 mg BID. Or azithromycin 500 mg → 250 mg daily (only if local resistance < 25%).
CAP -Outpatient, with comorbidities
Amoxicillin-clavulanate 875 mg BID + azithromycin
Or respiratory fluoroquinolone (levofloxacin 750 mg daily or moxifloxacin 400 mg daily) -monotherapy.
CAP -Inpatient (non-ICU)
Ceftriaxone 1–2g IV daily + azithromycin 500 mg IV daily STANDARD
Or respiratory FQ monotherapy. Duration: under 5 days, minimum 3, once clinically stable CHANGED 2025PTC (Dinh), 2021 -the 2025 ATS update prefers under 5 days here, where 2019 set the floor at 5. Stability first, then count.
CAP -ICU (severe)
Ceftriaxone (Rocephin) 2g IV + azithromycin (Zithromax) 500 mg IV
Add vancomycin or linezolid if MRSA risk factors (linezolid preferred if severe -superior lung penetration). Add piperacillin-tazobactam or cefepime if Pseudomonas risk. Always get blood cultures + sputum + Legionella/pneumococcal urine antigens. Duration: ≥ 5 daysSTRONG 2025 -severe CAP is explicitly excluded from the shorter-course recommendation, so do not apply the sub-5-day rule here.
HAP / VAP
Piperacillin-tazobactam (Zosyn) 4.5g IV q6h or cefepime 2g IV q8h or meropenem
Add vancomycin or linezolid for MRSA (linezolid if severe -superior lung penetration). Duration: 7 daysATS/IDSA HAP/VAP Guidelines, 2016. Shorter is better -reduces resistance.
Aspiration
Treat like CAP (ceftriaxone + azithro)
Anaerobes are NOT the primary cause -same organisms as CAP. Add anaerobic coverage (amp-sulbactam or pip-tazo) ONLY if: lung abscess, empyema, necrotizing PNA, or poor dentition + indolent course. Aspiration pneumonitis (chemical) = NO antibiotics.
⚠️ AKI risk with vancomycin: observational data long suggested pip-tazo + vanc raises AKI, but the only RCT found no difference in its primary AKI/death endpoint ACORN, 2023Pip-Tazo Nephrotoxicity Study, 2017. If using both, monitor Cr closely.
💊 Cefepime
Coverage: Pseudomonas + gram-negatives. NO anaerobic coverage.
HAP/VAP without anaerobic concern -standard nosocomial pneumonia
Often paired with vancomycin when anaerobic cover is not needed. Note the AKI rationale did not survive the RCT ACORN, 2023
Neutropenic fever (first-line IDSA, 2010)
CKD/AKI patients on vancomycin -safer renal profile
No suspected anaerobic infection
⚠️ Neurotoxicity: Cefepime can cause seizures and encephalopathy, especially in renal impairment. Dose-adjust for CrCl. Monitor mental status.
Bottom line: Use pip-tazo when you need anaerobic coverage (aspiration with abscess/empyema, intra-abdominal source, necrotizing infection). Use cefepime when you don't need anaerobes -especially when pairing with vancomycin (lower nephrotoxicity). If you need cefepime + anaerobic coverage, add metronidazole 500 mg IV q8h separately.
MRSA risk factors: prior MRSA isolation, IV drug use, hospitalization within 90 days, hemodialysis, nursing home/LTAC residence. Pseudomonas risk: structural lung disease (bronchiectasis, CF), IV antibiotics within 90 days, prior Pseudomonas culture, immunosuppression.
🔄 Updated Practice: Old teaching: all "healthcare-associated" patients need MRSA coverage. HCAP was eliminated from 2019 ATS/IDSA guidelines because it led to massive overtreatment. Instead, get a nasal MRSA PCR swab -negative result has ~95% negative predictive value for MRSA pneumonia and can safely guide de-escalation.
Linezolid vs Vancomycin -Quick Decision Guide
Both cover MRSA, but they're NOT interchangeable. For MRSA pneumonia specifically, linezolid may be superior due to lung penetration. Know when to pick each.
🧫 Toxin Suppression -Linezolid & Clindamycin: Both inhibit the 50S ribosome → suppress bacterial toxin production. Critical in: necrotizing fasciitis (GAS exotoxins), toxic shock syndrome (TSST-1), PVL-producing MRSA. Vancomycin kills the bug but does NOT stop toxin release. In toxin-mediated disease, always add a protein synthesis inhibitor (clindamycin or linezolid).
⚠️ Linezolid Side Effects to Know: Thrombocytopenia (> 14d -CBC twice weekly), lactic acidosis (weekly lactate if prolonged), peripheral neuropathy & optic neuritis (> 28d -may be irreversible), serotonin syndrome (weak MAOi -avoid with SSRIs/SNRIs/tramadol). If on SSRI → use vancomycin. Never use daptomycin for pneumonia -pulmonary surfactant inactivates it.
📋 Clinical Example -CAP Severity & Antibiotic Choice
Patient: 55M, cough with yellow sputum × 5 days, fever 38.9°C, RR 22, SpO₂ 94% on RA, CXR: RLL consolidation.
Severity -CURB-65: Confusion (0), BUN > 19 mg/dL (0), RR ≥ 30 (0), BP < 90 systolic (0), Age ≥ 65 (0) = Score 0 → outpatient treatment appropriate.
OR levofloxacin (Levaquin) 750mg PO/IV daily (respiratory fluoroquinolone monotherapy -reserve for PCN allergy or failure of beta-lactam)
When to add MRSA coverage (vanc or linezolid): Prior MRSA infection/colonization, cavitary infiltrate, empyema, recent influenza, or severe necrotizing pneumonia. Get nasal MRSA swab -negative PCR has ~95% NPV for MRSA pneumonia → can safely withhold MRSA coverage.
Duration:under 5 days, with a 3-day minimum, once the patient is clinically stable CHANGED 2025. Stability means afebrile, HR ≤ 100, RR ≤ 24, SBP ≥ 90, SpO₂ ≥ 90%, taking oral intake, and normal mental status. Severe CAP is the exception and gets ≥ 5 days (strong recommendation). No need for 7–14 days in anyone.
IV → PO switch: Once afebrile, tolerating PO, and clinically improving → switch to oral and discharge. Do not keep patients NPO or on IV abx waiting for "completion of course."
🔄 Updated Practice: Old teaching was 7–14 days. ATS/IDSA 2019 cut that to a 5-day floor. The 2025 ATS update goes shorter again: in the clinically stable outpatient or non-severe inpatient, under 5 days with a 3-day minimum is now preferred, on the strength of trials like PTC. Severe CAP is carved out and still gets ≥ 5 days. Longer courses increase C. difficile risk, resistance, and side effects without improving cure rates, which is why the floor keeps dropping.
When to Add Steroids in Pneumonia UPDATED 2025
Four clinical scenarios where steroids are indicated, each with its own drug, dose, and duration. The newest indication is severe CAP in the ICU (CAPE COD 2023, hydrocortisone cuts 28-day mortality 6.2% vs 11.9%, NNT ~18).
The guideline has now caught up with the trial. The 2025 ATS update makes systemic steroids in severe CAP a conditional recommendation FOR, reversing 2019, which suggested against them. In non-severe CAP the recommendation against is now strong (previously conditional), so the severity label is the entire decision: steroids help severe CAP and harm non-severe CAP.
Scenario
Indication
Drug & Dose
Duration
Why
Severe CAP in ICUNEW 2023
Any one of: intubated, HFNC FiO2 ≥ 0.5 with P/F < 300, NIV with P/F < 300, or PSI > 130
Hydrocortisone 200 mg IV daily (50 mg q6h or 8 mg/hr continuous infusion)
8 days if improving on day 4 (P/F > 200, breathing spontaneously, SOFA ≤ baseline). 14 days if not improving. Taper at end.
Dampens dysregulated lung inflammation that drives ARDS and shock in the sickest CAP patients. Older trials in non-severe CAP did not show mortality benefit because inflammation is not the rate-limiting step there. CAPE COD, 2023
PJP / PCP pneumonia
PaO2 < 70 mmHg on room air OR A-a gradient ≥ 35 mmHg. Most often HIV (CD4 < 200), also chemotherapy, transplant, chronic steroid users.
Prednisone 40 mg PO BID days 1-5, then 40 mg daily days 6-10, then 20 mg daily days 11-21
21 days total (overlapping the full TMP-SMX course)
Killing PJP releases organism debris that worsens acute lung injury in the first few days of treatment. Pretreating with steroids blunts the inflammatory surge. Mortality benefit only below the PaO2/A-a thresholds; mild PJP does not benefit. Start with or before the first TMP-SMX dose.
COVID-19 pneumonia
Hospitalized COVID requiring supplemental O2 or higher (HFNC, NIV, intubated, or ECMO)
Dexamethasone 6 mg PO/IV daily
Up to 10 days (or until discharge, whichever is sooner)
Reserve for the inflammatory phase of COVID (~7-10 days into illness) when lungs fail. RECOVERY, 2020. Higher doses (12 mg) tested in COVID-STEROID 2 without significant additional benefit, more side effects. Stick to 6 mg. Do NOT give to COVID patients NOT requiring oxygen (RECOVERY showed potential harm in this subgroup).
Septic shock from pneumonia
Vasopressor-dependent septic shock
Hydrocortisone 200 mg/day IV (50 mg q6h or 8 mg/hr continuous infusion)
Until shock resolves and pressors weaning, typically 5-7 days then taper
Shorter shock duration, modest mortality benefit in some subgroups. ADRENAL, 2018APROCCHSS, 2018. Surviving Sepsis 2026: conditional recommendation. Overlap with severe CAP: if a patient meets BOTH severe CAP criteria AND is in septic shock, the same hydrocortisone 200 mg/day satisfies both indications.
When NOT to give steroids in pneumonia.
Non-severe CAP (ward-level, not meeting CAPE COD criteria). Older trials showed shorter time to clinical stability but no mortality benefit; risks (hyperglycemia, infection, GI bleed) outweigh benefit. The 2025 ATS update strengthened this to a strong recommendation againstCHANGED 2025, so this is now one of the firmest statements in the guideline.
Suspected or confirmed influenza pneumonia. Associated with higher mortality in observational data; skip unless another indication exists (asthma exacerbation, septic shock).
Suspected fungal pneumonia, especially aspergillosis. Steroids worsen fungal disease.
Active untreated TB. Will disseminate.
Mild PJP (PaO2 > 70 AND A-a < 35 on room air). No mortality benefit, side effects without upside.
COVID-19 NOT requiring supplemental O2. RECOVERY showed potential harm in this subgroup.
📋 On Rounds
Can you use 5 days of antibiotics for CAP?
Yes. PTC (Dinh), 2021 and ATS/IDSA 2019 guidelines recommend minimum 5 days of antibiotics for CAP, with discontinuation once the patient is clinically stable for 48h (afebrile, HR < 100, RR < 24, SBP > 90, SpO₂ > 90%, able to eat, normal mentation). Longer courses do not improve outcomes and increase antibiotic resistance, C. diff risk, and adverse effects. The old "7–14 day" dogma is outdated.
When do you get blood cultures in pneumonia?
Not for all CAP. ATS/IDSA 2019 recommends cultures for: severe CAP (ICU admission), empiric MRSA or Pseudomonas coverage, prior positive cultures for these organisms, recent hospitalization + IV antibiotics within 90 days. Routine blood cultures in non-severe CAP have < 5% positivity rate and rarely change management. For HAP/VAP: always get blood cultures + respiratory cultures (sputum, endotracheal aspirate, or BAL)
When should you add MRSA coverage (vancomycin or linezolid) to CAP treatment?
MRSA coverage is NOT routine for CAP -add only with specific risk factors: (1) Prior MRSA isolation (respiratory culture, nasal swab), (2) Cavitary infiltrate or necrotizing pneumonia on imaging, (3) Concurrent influenza (post-influenza MRSA pneumonia is classic and rapidly fatal), (4) Severe pneumonia requiring ICU admission + risk factors. MRSA nasal swab (PCR) has high negative predictive value (> 95%)
HAP/VAP: when do you choose pip-tazo over cefepime?
Choose pip-tazo when you need anaerobic coverage -aspiration with lung abscess, empyema, necrotizing pneumonia, poor dentition with indolent course, or suspected intra-abdominal co-infection. Pip-tazo covers Pseudomonas + gram-negatives + anaerobes. Cefepime covers Pseudomonas + gram-negatives but has NO anaerobic activity.
What are the criteria for severe CAP requiring ICU admission?
ATS/IDSA 2019 criteria: 1 major criterion = ICU: (1) septic shock requiring vasopressors, (2) mechanical ventilation. ≥ 3 minor criteria = ICU: RR ≥ 30, PaO₂/FiO₂ ≤ 250, multilobar infiltrates, confusion, BUN ≥ 20, WBC < 4K, platelets < 100K, temperature < 36°C, hypotension requiring aggressive fluid resuscitation. Why it matters: severe CAP gets broader empiric coverage -ceftriaxone + azithromycin + vancomycin (if MRSA risk)
Clinical Examples
📋 Case 1, Standard Inpatient CAP with Short-Course Antibiotics
Patient: 72 y/o F with COPD and HTN, presents with 3 days of productive cough, fever 38.6°C, and dyspnea.
Ceftriaxone 1g IV daily + azithromycin 500 mg IV daily (standard non-ICU inpatient regimen)
Supplemental O₂ to maintain SpO₂ ≥ 92%
Afebrile x48h + improving → transition to PO and discharge
Total duration: 5 days PTC (Dinh), 2021, do not extend for persistent CXR abnormality
Teaching point: The old 7-14 day antibiotic course for CAP is outdated. ATS/IDSA 2019 recommends minimum 5 days, stopping once clinically stable x48h. Longer courses increase C. difficile risk and resistance without improving outcomes.
📋 Case 2, Severe CAP with MRSA Risk
Patient: 58 y/o M with IVDU history, presents with high fever, productive cough with blood-tinged sputum, and hypoxia. Recent hospitalization 6 weeks ago.
Key findings: HR 118, BP 86/52, RR 32, SpO₂ 84% on 15L NRB. CXR: multilobar cavitary infiltrates. WBC 22K, lactate 4.8, procalcitonin 18.2. Intubated for respiratory failure.
Management:
Meets ATS/IDSA major criterion for severe CAP (mechanical ventilation), ICU admission
MRSA nasal swab sent, if negative (NPV > 95%), de-escalate vancomycin at 48h
Blood cultures, sputum culture, Legionella and pneumococcal urine antigens
Teaching point: MRSA nasal swab PCR has > 95% negative predictive value, it is the best antibiotic stewardship tool for de-escalating vancomycin. Cavitary infiltrates, necrotizing pneumonia, and post-influenza pneumonia are classic MRSA scenarios.
📋 Case 3, Aspiration Pneumonia vs Chemical Pneumonitis
Patient: 80 y/o M with advanced dementia and dysphagia, witnessed aspiration during feeding. Develops cough and fever 12h later.
Distinguish aspiration pneumonitis (chemical, sterile) from aspiration pneumonia (bacterial infection)
If symptoms develop > 24-48h after aspiration event with rising WBC/PCT → treat as bacterial aspiration PNA
Antibiotics: ceftriaxone + azithromycin (same as CAP, anaerobes are NOT the primary cause)
Add anaerobic coverage (amp-sulbactam or pip-tazo) ONLY if abscess, empyema, or necrotizing PNA
Teaching point: Chemical pneumonitis (within hours of aspiration, sterile inflammation) does NOT need antibiotics. Bacterial aspiration pneumonia is treated like CAP, the old teaching of routine anaerobic coverage with clindamycin is outdated unless there is abscess or necrotizing disease.
📣 Sample Presentation
One-Liner
"Mrs. Evans is a 72-year-old with COPD presenting with 3 days of productive cough, fever 38.6°C, and dyspnea. CXR: right lower lobe consolidation. WBC 16K, procalcitonin 2.8. CURB-65 score 2 (age + BUN 24). Admitted for CAP."
Key Points to Cover on Rounds
CAP -CURB-65 2 (inpatient). Antibiotics: ceftriaxone 1g IV daily + azithromycin 500 mg IV daily (standard non-ICU inpatient regimen). Blood cultures × 2 drawn (before abx). Sputum culture sent. O₂: 3L NC (SpO₂ 93%). Procalcitonin 2.8 (supports bacterial etiology). No MRSA risk factors -vancomycin not added. Influenza/COVID tested (negative). Response at 48h: afebrile, WBC trending 16→12. Plan: step down to PO (levofloxacin or amox-clav + azithro) when tolerating PO + afebrile ×24h. Total duration: 5 days if stable ×48h Uranga, 2016. Follow-up CXR in 6-8 weeks (rule out underlying mass).
Imaging: CXR PA + lateral (infiltrate, consolidation, effusion). CT chest if CXR equivocal or complications suspected. Lung ultrasound is an acceptable alternative to the chest radiographNEW 2025 where the expertise and a standardized protocol exist, which matters most when the patient cannot travel or you want an answer at the bedside. Routine follow-up imaging is not recommended if symptoms resolve within 5–7 days; infiltrates lag clinical cure by weeks
Respiratory viral PCR: send whenever influenza or SARS-CoV-2 is circulating. A positive result starts an antiviral, and in a healthy outpatient with no comorbidities it now justifies withholding antibiotics entirelyNEW 2025. Outpatients with comorbidities, and every hospitalized patient, still get antibiotics regardless of the viral result
Urine antigens:Legionella (serogroup 1) + S. pneumoniae -order in ICU-level or severe CAP
Procalcitonin: < 0.25 → bacterial unlikely. Serial levels guide antibiotic de-escalation (drop > 80% from peak → safe to stop). Never use it to withhold initial antibiotics in radiographically confirmed CAP; its role is to support stopping, not starting
Do NOT delay antibiotics for cultures. In sepsis, every hour of delay increases mortality. Draw cultures → give abx immediately.
💊 Medications
Medications -Pneumonia
Full antibiotic regimens are in the Treatment tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Classification Drives the Antibiotic
CAP: onset in the community.HAP: 48 h or more after admission.VAP: 48 h or more after intubation.HCAP no longer exists: ATS/IDSA eliminated it in 2016 because treating nursing home residents and dialysis patients as HAP led to unnecessary broad-spectrum therapy without better outcomes. Use individual risk factors for resistance instead.
Use the Right Score for the Right Question
CURB-65 and PSI are severity scores that guide site of care.The IDSA/ATS 2019 severe CAP definition, one major or three or more minor criteria, is what triggers ICU-level care.Severity determines where the patient goes and how closely they are watched; it does not by itself broaden the antibiotic.
Standard Empiric CAP Therapy
Inpatient non-severe: a beta-lactam plus a macrolide, or a respiratory fluoroquinolone.Outpatient healthy: amoxicillin, doxycycline or a macrolide where resistance is low.The combination beats beta-lactam alone in hospitalized patients, and the macrolide contributes both atypical coverage and an anti-inflammatory effect.
Add MRSA or Pseudomonas Cover Only on Risk Factors
Prior isolation of the organism, recent hospitalization with IV antibiotics in the last 90 days, or locally validated risk factors.Do not add vancomycin and piperacillin-tazobactam to every admitted pneumonia: it causes acute kidney injury and C. difficile without improving outcomes in patients without those risks. De-escalate at 48 h on culture and MRSA nasal PCR, whose high negative predictive value safely stops vancomycin.
Get Cultures in the Right Patients Only
Blood and sputum cultures for severe CAP, ICU admission, cavitary disease, and those being treated for MRSA or Pseudomonas.Routine cultures in mild outpatient-managed CAP rarely change management. Add urinary pneumococcal and Legionella antigens in severe disease and in outbreaks.
Treat for 5 Days in Most Cases
Five days is sufficient if the patient is afebrile for 48 h and clinically stable, and longer courses do not improve outcomes. Extend for complications: empyema, lung abscess, bacteremia, or an unusual organism such as Pseudomonas or S. aureus.
Steroids Only in Severe Disease
Hydrocortisone reduces mortality in severe CAP requiring ICU care (CAPE COD), but routine steroids in non-severe pneumonia offer no benefit and cause hyperglycemia and superinfection.Avoid them in influenza pneumonia, where they are associated with harm.
Reassess the Non-Responder Rather Than Broadening
Failure to improve by 48 to 72 h means look for empyema, abscess, obstruction, the wrong organism (tuberculosis, fungal, PJP) or the wrong diagnosis, including pulmonary embolism, heart failure and organizing pneumonia. Image before escalating antibiotics. Before discharge: vaccinate, address smoking, and arrange a follow-up chest film in smokers and those over 50 to exclude an underlying malignancy.
Incidental pulmonary nodules are found on ~30% of chest CTs. Most are benign. The key is risk-stratifying: size, morphology, growth, and patient risk factors determine surveillance vs biopsy vs resection.
🔍 Nodule Workup
Fleischner Society Guidelines (2017) -Solid Nodules
Size
Low Risk (< 5% malignancy)
High Risk (≥ 5% malignancy)
< 6 mm
No follow-up needed
Optional CT at 12 months
6–8 mm
CT at 6–12 months, then consider CT at 18–24 months
CT at 6–12 months, then CT at 18–24 months
> 8 mm
CT at 3 months, PET-CT, or tissue sampling depending on clinical probability
High-Risk Features
Patient: smoking history, older age, family history of lung cancer, prior cancer, occupational exposures
Nodule: upper lobe location, spiculated margins, growth on serial imaging, part-solid morphology, > 8 mm
Ground-Glass and Part-Solid Nodules (GGN/PSN)
Pure ground-glass < 6 mm: no follow-up
Pure ground-glass ≥ 6 mm: CT at 6–12 months, then q2 years × 5 years
Part-solid (mixed) ≥ 6 mm: CT at 3–6 months. If solid component ≥ 6 mm and persists → PET or biopsy. Part-solid nodules have the highest malignancy rate of any morphology.
Stability for 2 years on serial CT does NOT guarantee benignity for ground-glass nodules -GGNs (often adenocarcinoma in situ) can be indolent for years before becoming invasive. Follow for 5 years minimum.
🔬 Lung Cancer Screening
LDCT Screening Criteria (USPSTF 2021)
Age 50–80 years
≥ 20 pack-year smoking history
Currently smoke or quit within the past 15 years
Annual low-dose CT (LDCT) -no IV contrast
NLST, 2011: LDCT screening reduced lung cancer mortality by 20% vs chest X-ray. NELSON, 2020: confirmed 24% reduction in lung cancer mortality in men, 33% in women.
Shared decision-making required. Discuss benefits (mortality reduction), harms (false positives, radiation, anxiety, unnecessary procedures), and the importance of smoking cessation (which reduces mortality far more than screening).
📋 On Rounds
Which nodule morphology has the highest malignancy rate?
Part-solid (mixed ground-glass and solid) nodules. They have a malignancy rate up to ~60% if they persist -higher than either pure solid or pure ground-glass nodules. The solid component usually represents the invasive component of an adenocarcinoma, while the ground-glass component represents in situ or minimally invasive disease.
When do you get a PET-CT for a pulmonary nodule vs just follow-up CT?
PET-CT is indicated for solid nodules ≥ 8 mm with intermediate probability of malignancy (5–65% based on clinical risk). PET has ~90% sensitivity for malignancy but false negatives occur with: (1) nodules < 8 mm (below PET resolution), (2) GGOs/lepidic adenocarcinoma (low metabolic activity), (3) carcinoid tumors. False positives occur with: infection (TB granulomas, fungal), inflammation, sarcoidosis.
What makes a pulmonary nodule more likely to be malignant?
Higher risk features: (1) Size: > 8 mm (malignancy risk increases exponentially with size -6 mm = 1%, 20 mm = 15-20%), (2) Morphology: part-solid (HIGHEST malignancy rate of any type), spiculated margins, irregular shape, (3) Location: upper lobe (lung cancer more common), (4) Growth: any growth on serial imaging is concerning (doubling time 20-400 days for malignancy vs > 400 for benign)
How do you counsel a patient about an incidental pulmonary nodule?
This is a common and anxiety-provoking conversation. Key points: (1) Most nodules are benign -even in smokers, a 6 mm nodule has only ~1% chance of malignancy. Explain this clearly. (2) Follow-up is about tracking change -"we're watching to see if it grows. If it stays the same size over 2 years, it's almost certainly not cancer." (3) Specific follow-up plan with dates -"you'll need a repeat CT scan in [3/6/12] months.
Clinical Examples
📋 Case 1, Incidental Solid Nodule in a Smoker
Patient: 58M, 30-pack-year smoker. CT chest for cough reveals incidental 14 mm solid RUL nodule with spiculated borders. No prior CT for comparison. No symptoms concerning for malignancy.
Key findings: High-risk features: > 8 mm, solid, spiculated margins, upper lobe location, smoker > 30 pack-years. Fleischner Society guidelines: solid nodule > 8 mm in high-risk patient → PET/CT or tissue sampling.
Management:
PET/CT, FDG avidity suggests malignancy (SUV > 2.5 has ~90% sensitivity for malignant nodules > 8 mm)
If PET-avid: CT-guided biopsy or navigational bronchoscopy for tissue diagnosis
If biopsy confirms NSCLC: staging with brain MRI → surgical resection if early stage (lobectomy + mediastinal lymph node dissection)
If PET-negative: CT surveillance at 3 months, then annually × 2-3 years (false negatives occur with low-grade adenocarcinoma)
Low-dose CT lung cancer screening annually (meets USPSTF criteria: age 50-80, ≥ 20 pack-years)
Teaching point: Spiculated margins are the single most concerning morphologic feature for malignancy (~90% PPV). Smooth, well-defined margins favor benign, but do not rule out cancer. Size + morphology + risk factors together determine the approach.
📋 Case 2, Small Incidental Ground-Glass Nodule
Patient: 45F never-smoker. CT PE study (negative for PE) incidentally shows a 6 mm pure ground-glass nodule (GGN) in the LLL. No solid component. No prior imaging.
Key findings: Pure GGN 6 mm, these are almost always preinvasive adenocarcinoma (AIS/MIA) or atypical adenomatous hyperplasia if persistent. Very slow-growing, doubling time often > 800 days. Low risk of metastasis even if malignant.
Management:
Fleischner 2017: 6 mm pure GGN → follow-up CT at 6-12 months to confirm persistence
If persistent: CT annually × 5 years (these grow very slowly, long surveillance needed)
No PET/CT (pure GGNs are often PET-negative even if malignant, low metabolic activity)
No biopsy unless growing or developing solid component
If develops solid component (> 5 mm solid): reclassify as part-solid → more aggressive workup
Teaching point: Pure GGNs are indolent, even when malignant (AIS/MIA), they rarely metastasize. The danger is the development of a solid component, which transforms the prognosis. Part-solid nodules with solid component > 5 mm have the highest malignancy risk of all nodule types.
📋 Case 3, Multiple Nodules on Lung Cancer Screening
Patient: 62M, 35-pack-year smoker. Annual LDCT screening shows 3 new nodules: 4 mm solid RML, 7 mm solid RUL, and 9 mm part-solid LUL (6 mm solid component). No prior nodules.
Key findings: Multiple nodules with one dominant suspicious nodule (9 mm part-solid with 6 mm solid component). Lung-RADS 4B. The part-solid nodule with substantial solid component is the most concerning, warrants tissue diagnosis.
Management:
Dominant nodule (9 mm part-solid): PET/CT → if avid, navigational bronchoscopy or CT-guided biopsy
4 mm solid: Fleischner → follow-up CT at 12 months (low risk at this size)
7 mm solid: short-interval CT at 3 months or PET/CT given smoking history
If dominant nodule = cancer: full staging → may need PET/CT of all nodules (separate primaries vs metastases)
Continue annual LDCT screening regardless of this finding
Teaching point: With multiple nodules, manage based on the most suspicious nodule. Part-solid nodules with solid component ≥ 6 mm have the highest malignancy risk (~60%). Multiple nodules in a smoker are more likely separate primary lung cancers than metastases from a single primary.
📣 Sample Presentation
One-Liner
"Ms. Kim is a 55-year-old smoker whose CT chest for cough incidentally found a 12 mm solid right upper lobe pulmonary nodule. No prior imaging for comparison."
Key Points to Cover on Rounds
Incidental 12 mm solid RUL nodule in a smoker -intermediate-to-high malignancy risk. Per Fleischner: solid nodule ≥8 mm → consider CT at 3 months, PET-CT, or tissue sampling depending on clinical probability. Given risk factors (smoker, upper lobe, >8 mm): PET-CT ordered. If PET avid → CT-guided biopsy or surgical excision. If PET negative → CT follow-up at 3, 6, 12, 24 months. Lung-Rads if found on screening LDCT. Patient counseled about findings and follow-up plan documented. Smoking cessation strongly reinforced. Pulmonology referral placed.
🧪 Workup
Workup
See the Overview and Management tabs for the pulmonary nodule workup (Fleischner algorithm by size + morphology + risk, PET-CT for solid nodules ≥ 8mm with intermediate probability, biopsy vs serial CT decision, and Lung-Rads for screening-detected nodules).
💊 Medications
Medications
Pulmonary nodule evaluation is primarily diagnostic, there are no disease-specific pharmacotherapies. Agents involved are procedural (contrast for CT/PET, sedatives for biopsy) or directed at confirmed lung malignancy (see Oncology topics for lung cancer-specific regimens).
⚡ Summary
Most Are Benign
Incidental nodules appear on roughly 30% of chest CTs, and the great majority are not cancer.Risk-stratify on size, morphology, growth and patient factors rather than reflexively biopsying or reflexively ignoring. The point of the guidelines is to avoid both extremes.
Follow Fleischner for Solid Nodules
Under 6 mm in a low-risk patient: no routine follow-up.Under 6 mm in a high-risk patient: optional CT at 12 months.6 to 8 mm: CT at 6 to 12 months, then 18 to 24 months.Above 8 mm: consider CT at 3 months, PET-CT or tissue sampling.These apply to incidental nodules in adults over 35, not to screening findings, immunosuppressed patients or known cancer.
Morphology and Location Change the Probability
Spiculated margins, upper lobe location and growth raise suspicion.Benign calcification patterns, central, laminated, popcorn or diffuse, effectively exclude malignancy, whereas eccentric or stippled calcification does not. Fat within a nodule means hamartoma.
Ground-Glass Nodules Follow Different Rules
Two years of stability does not guarantee benignity.Ground-glass nodules, often adenocarcinoma in situ, can be indolent for years before becoming invasive, so follow them for at least 5 years.A part-solid nodule with a growing solid component is the concerning pattern, and the solid portion size is what predicts invasiveness.
PET Has Real Limits
It is unreliable below about 8 mm, and it is falsely negative in ground-glass lesions, carcinoid and mucinous adenocarcinoma.False positives occur in infection, granulomatous disease and inflammation, which matters greatly in regions endemic for histoplasmosis and coccidioidomycosis. A negative PET in a suspicious nodule does not close the case.
Screen the Right Population
Annual low-dose CT from 50 to 80, with a 20 pack-year history, in current smokers or those who quit within 15 years (USPSTF 2021, which lowered the age and pack-year thresholds). Stop screening once 15 years have passed since quitting, or when a health problem limits life expectancy or the willingness to have curative surgery.
Screening Requires Shared Decision-Making
Discuss the mortality benefit alongside the harms: false positives, incidental findings, radiation, anxiety and unnecessary procedures. Smoking cessation reduces mortality far more than screening does, so the screening visit is also the cessation visit, and framing it that way is the highest-yield part of the conversation.
Choose the Diagnostic Route by Location and Fitness
Peripheral lesions: CT-guided transthoracic biopsy, with a real pneumothorax rate.Central lesions: bronchoscopy, increasingly navigational.A high-probability nodule in a good surgical candidate may go straight to resection, since a negative biopsy in that setting rarely changes the plan. Discuss at a multidisciplinary meeting, and always compare with prior imaging first, which resolves many nodules without any further test.
🔍 Overview
Overview -Pulmonary Nodule & Lung Cancer Screening
See the tabs above for the complete clinical reference: Workup, Management, Medications, Monitoring, Rounds, Summary, and One Pager.
< 6 mm: no routine follow-up. 6–8 mm: CT at 6–12 mo, then 18–24 mo. > 8 mm: CT at 3 mo, PET-CT, or tissue sampling. Multiple nodules → follow most suspicious. Part-solid: lower threshold for biopsy; follow 5 years.
💊 Key Actions
CT follow-upPer Fleischner timing
PET-CTIntermediate probability, ≥ 8mm
BiopsyPET-avid or high suspicion
LDCT screeningPer Lung-Rads classification
⚠️ Pitfalls
Lost to follow-up (major malpractice risk -document and schedule)
Part-solid nodules dismissed as benign (highest malignancy rate)
Not considering malignancy in smoker > 50 with new nodule
Fleischner applied to screening LDCT (use Lung-Rads instead)
Pulmonary function tests -spirometry, lung volumes, and DLCO. A systematic approach: (1) FEV₁/FVC ratio, (2) lung volumes, (3) DLCO. This tells you obstructive vs restrictive vs mixed, and narrows the differential.
Low FVC with normal FEV₁/FVC does NOT confirm restriction. Air trapping in obstruction can reduce FVC, making the ratio look normal. You need lung volumes (TLC) to confirm restriction. TLC < 80% predicted = true restriction.
Step 2 -Bronchodilator Response
Positive response: FEV₁ or FVC improves ≥ 12% AND ≥ 200 mL after albuterol ATS/ERS Spirometry Standardization, 2005
Both are obstructive (FEV₁/FVC < 0.70). Key differences: (1) Bronchodilator response: asthma shows significant reversibility (≥ 12% + 200 mL), COPD has minimal reversibility. (2) DLCO: asthma has normal or increased DLCO, emphysema has decreased DLCO (alveolar destruction). (3) Methacholine challenge: positive in asthma (bronchial hyperresponsiveness), negative in COPD
A patient has low DLCO with normal spirometry. What's your differential?
Pulmonary vascular disease is the classic answer: pulmonary hypertension, chronic PE, or pulmonary arteriovenous malformations -the vascular bed is compromised but the airways and parenchyma are intact, so spirometry is normal.
How do you differentiate asthma from COPD on PFTs?
Both show obstruction (FEV₁/FVC < 0.70). The key differentiator: bronchodilator reversibility. Asthma: FEV₁ improves ≥ 12% AND ≥ 200 mL after bronchodilator (significant reversibility -airway obstruction is dynamic). COPD: FEV₁ improves < 12% or < 200 mL (fixed obstruction -structural airway damage). Other clues: DLCO: normal in asthma (parenchyma is fine), LOW in COPD/emphysema (alveolar destruction).
What does a low DLCO tell you, and what conditions have normal DLCO?
Low DLCO (reduced gas transfer across the alveolar membrane): (1) Emphysema -destroyed alveoli → reduced surface area for gas exchange. (2) ILD/pulmonary fibrosis -thickened interstitium → diffusion barrier. (3) Pulmonary hypertension -vascular bed destruction. (4) Anemia -less hemoglobin to bind CO (correct DLCO for Hgb). (5) Pulmonary embolism -dead space.
Teaching point: FEV₁/FVC < 0.70 = obstruction. The FEV₁ alone determines severity (GOLD staging). Bronchodilator response distinguishes COPD (minimal) from asthma (significant: ≥ 12% AND ≥ 200 mL). But there is overlap, some patients have both.
Key findings: Restrictive pattern: reduced TLC (< 80%) with preserved or elevated FEV₁/FVC ratio. Very low DLCO = impaired gas exchange (fibrosis thickens alveolar-capillary membrane). HRCT needed to determine cause.
Management:
HRCT chest, look for UIP pattern (honeycombing, traction bronchiectasis = IPF) vs NSIP pattern (GGO predominant = potentially treatable)
If UIP pattern: antifibrotic therapy (pirfenidone or nintedanib)
Serial PFTs q3-6 months, FVC decline > 10% absolute or DLCO decline > 15% = disease progression
6-minute walk test (6MWT), desaturation > 4% = significant; supplemental O₂ if SpO₂ < 88%
Early lung transplant referral if FVC < 80% or DLCO < 40% at diagnosis
Teaching point: FVC is the most important PFT for monitoring ILD progression, a 10% absolute decline in FVC over 6-12 months doubles mortality risk. DLCO is the most sensitive early marker but also declines with anemia and pulmonary HTN.
📋 Case 3, Mixed Obstructive-Restrictive Pattern
Patient: 58M with COPD and morbid obesity (BMI 48). PFTs: FEV₁ 45%, FVC 52%, FEV₁/FVC 0.62, TLC 72%, DLCO 55%. Lung volumes show decreased TLC but elevated RV/TLC ratio.
Key findings: Mixed pattern: FEV₁/FVC < 0.70 (obstruction) + TLC < 80% (restriction). Common in COPD + obesity, COPD + ILD overlap, or sarcoidosis. The reduced TLC from obesity masks hyperinflation from COPD.
Management:
Separate the contributions: body plethysmography (most accurate TLC) + chest imaging to assess parenchyma
Treat both: bronchodilators for COPD component + weight loss for restrictive component
Weight loss target: 10% body weight → expect ~5-10% improvement in FVC
If DLCO disproportionately low for the degree of obstruction: consider concurrent ILD or pulmonary HTN
ABG if concern for OHS (BMI > 40 + daytime hypercapnia)
Teaching point: A "normal" FEV₁/FVC ratio in a patient with low FVC does NOT rule out obstruction, both FEV₁ and FVC may be proportionally reduced ("pseudo-normalization"). Always check lung volumes (TLC) to confirm true restriction.
📣 Sample Presentation
One-Liner
"Mr. Johnson is a 62-year-old with 40-pack-year smoking history referred for PFTs. Results: FEV₁ 48% predicted, FVC 82%, FEV₁/FVC 0.58, DLCO 55%. Post-bronchodilator FEV₁ improvement: 8% and 120 mL."
Key Points to Cover on Rounds
Obstructive pattern (FEV₁/FVC 0.58, <0.70). GOLD classification: FEV₁ 48% = GOLD stage III (severe). Bronchodilator response: 8% and 120 mL (negative -doesn't meet 12% AND 200 mL threshold for significant reversibility → supports COPD over asthma). DLCO 55% (low -suggests emphysema component). Correlation: CT chest shows upper lobe centrilobular emphysema. Current treatment: LAMA only. Recommended: add ICS/LABA (triple therapy if exacerbation history). Pulmonary rehab referral. Reassess for LTOT if SpO₂ <88% at rest or exertion. Annual PFTs to track decline.
Monitoring
PFTs q6-12mo
FVC decline >5-10%/yr in ILD → escalate
DLCO <40% → O₂+transplant eval
6MWT
⚡ Summary
Summary
Read Them in Three Steps
FEV1/FVC ratio first, then lung volumes, then DLCO. That sequence separates obstructive from restrictive from mixed disease and then narrows the differential within each. Reading DLCO before establishing the pattern leads to misinterpretation, because the same DLCO means different things in obstruction and restriction.
Step 1: The Ratio Defines Obstruction
FEV1/FVC below 0.70 (or below the lower limit of normal) means obstruction, and then FEV1 percent predicted grades its severity. A normal ratio does not mean normal lungs: it just means the problem is not obstruction.
Low FVC Alone Does Not Prove Restriction
Air trapping in obstruction reduces FVC and can make the ratio look normal.You need lung volumes to confirm restriction: TLC below 80% predicted.Calling a low FVC 'restriction' without a TLC is the commonest PFT interpretation error, and it sends patients down an interstitial lung disease workup they do not need.
Step 2: Bronchodilator Response
A significant response is a 12% and 200 mL improvement in FEV1 or FVC.It supports asthma but does not exclude COPD, since a proportion of COPD patients respond, and asthmatics can have a normal response on a good day. Persistent obstruction after bronchodilator is what defines COPD.
Step 3: DLCO Splits Each Pattern in Two
Obstruction with a low DLCO: emphysema, where alveolar surface is destroyed.Obstruction with a normal or high DLCO: asthma or chronic bronchitis.Restriction with a low DLCO: interstitial lung disease, a parenchymal problem.Restriction with a normal DLCO: extraparenchymal, so neuromuscular weakness, obesity, kyphoscoliosis or pleural disease.
Correct DLCO for Hemoglobin
Anemia lowers the measured DLCO and polycythemia raises it, because the test depends on hemoglobin binding carbon monoxide. An uncorrected value in an anemic patient looks like interstitial disease that is not there. A raised DLCO also occurs in alveolar hemorrhage, asthma, obesity and left-to-right shunt.
Distinguish Neuromuscular Restriction
Check maximal inspiratory and expiratory pressures, and a supine FVC.A fall of more than about 10% in FVC from sitting to supine indicates diaphragmatic weakness, which is what separates neuromuscular restriction from parenchymal disease and is the measure that matters in ALS and myasthenia.
Check Effort and the Flow-Volume Loop Before Believing Anything
Poor effort or poor technique invalidates the study, so look at the reproducibility criteria before interpreting a number. The loop shape diagnoses upper airway obstruction: flattened inspiratory limb means a variable extrathoracic lesion (vocal cord dysfunction), flattened expiratory limb means variable intrathoracic, and both flattened means a fixed lesion such as tracheal stenosis. These are entirely missed if only the numbers are read.
Low: emphysema, ILD, pulmonary HTN, anemia, PE. Normal with obstruction: asthma. Elevated: pulmonary hemorrhage, polycythemia, left-to-right shunt. Best test to differentiate asthma from emphysema.
💊 Key Drugs
Bronchodilator testAlbuterol → repeat spirometry
Methacholine challengeIf normal PFTs + suspected asthma
Lung volumesBody plethysmography for TLC
DLCOGas transfer assessment
⚠️ Pitfalls
Diagnosing restriction without lung volumes (need TLC)
Missing asthma vs COPD distinction (reversibility + DLCO)
Not correcting DLCO for anemia
Ignoring the flow-volume loop (upper airway obstruction)
Air in the pleural space. Primary spontaneous (tall thin young male, no lung disease), secondary (COPD, CF), traumatic, or iatrogenic. Tension pneumothorax = clinical diagnosis → needle decompress, don't wait for CXR.
🔍 Overview
Types
Type
Cause
Key Features
Primary spontaneous (PSP)
Rupture of apical bleb/bulla in otherwise healthy lung
Tall, thin, young male, smoker. Usually small. Low recurrence after first episode (~30%), high after second (~50%).
The Types table above gives the high-level categories. The high-yield differential below is what to look for on history, imaging, and bedside evaluation.
Pneumocystis jirovecii pneumonia (PCP) -HIV/AIDS or other immunocompromise. Can cause bilateral PTX. High recurrence.
Tuberculosis (cavitary) -endemic exposure, weight loss, night sweats, cavitary lesion on imaging.
Secondary Spontaneous: Cystic / Bullous
Lymphangioleiomyomatosis (LAM) -young woman of reproductive age with recurrent PTX. Tuberous sclerosis association, renal angiomyolipomas. Treat with sirolimus.
Ehlers-Danlos (vascular type, COL3A1) -hyperextensible skin, joint laxity. Vessel and organ rupture risk.
Secondary Spontaneous: Special
Catamenial pneumothorax (thoracic endometriosis) -right-sided, recurrent, within 24-72h of menses in reproductive-age women. Treat with hormonal suppression plus VATS.
Lung malignancy (primary or metastatic) -cavitary lesion erodes into pleura. Smoker, weight loss.
Traumatic
Blunt chest trauma -rib fracture lacerating pleura. MVC, fall, sports injury. Often associated with hemothorax.
Penetrating trauma -stab wound, gunshot. Open ("sucking") chest wound: cover with three-sided dressing.
Barotrauma -diving (rapid ascent without exhalation), blast injury. Concomitant air embolism risk.
Iatrogenic
Central line placement (subclavian > IJ) -~1-3% rate even with ultrasound guidance. Always get post-line CXR.
Thoracentesis / pleural drainage -~3% with US guidance, > 10% without.
CT-guided transthoracic needle biopsy -highest iatrogenic rate (~15-20%). Most resolve with observation alone.
Mechanical ventilation barotrauma -high PEEP, high tidal volumes, ARDS. Watch for progression to tension PTX, especially in patients with bullous disease.
CPR -rib fractures, occasionally direct pleural injury. Always check post-resuscitation CXR after prolonged or vigorous CPR.
High-yield clue patterns:
Tall thin young male, sudden pleuritic pain at rest: primary spontaneous (apical bleb).
Recurrent right-sided PTX in reproductive-age woman, around menses: catamenial / thoracic endometriosis.
Young woman with renal angiomyolipomas, recurrent PTX: LAM (check for tuberous sclerosis).
HIV with bilateral PTX: PCP until proven otherwise.
Post-procedure PTX in a previously stable patient: recently placed line, biopsy, or thoracentesis.
🚨 Management
Management by Size and Type
Scenario
Management
Small PSP (< 2 cm at apex), stable
Observation + high-flow O₂ (accelerates reabsorption 4×). Repeat CXR in 4–6h. Discharge if stable and improving.
Large PSP (≥ 2 cm) or symptomatic
Needle aspiration (14–16G, 2nd ICS) → recheck CXR. If re-expands → observe. If fails → chest tube. BTS Guidelines, 2023: aspiration first-line for PSP.
SSP -any size
Chest tube (14–28 Fr) connected to water seal or low suction (−20 cmH₂O). These patients have no reserve. Do NOT just observe SSP.
Tension PTX
Immediate needle decompression → chest tube. Do not wait for CXR.
Recurrent PSP (≥ 2 episodes ipsilateral)
VATS with pleurodesis (mechanical or chemical). Recurrence after first: ~30%. After VATS: < 5%.
High-flow O₂ (15 L/min via non-rebreather) accelerates pneumothorax reabsorption by creating a nitrogen gradient -the pleural air (mostly N₂) is absorbed faster when alveolar N₂ is reduced. Speeds reabsorption from ~1.25%/day to ~5%/day.
📋 On Rounds
Why does high-flow O₂ speed pneumothorax reabsorption?
Pleural air is ~78% nitrogen. High-flow O₂ washes nitrogen out of the blood (by displacing it in the alveoli), creating a partial pressure gradient for N₂ between the pleural space and the capillary blood. This draws N₂ from the pleural collection into the bloodstream, where it's exhaled. The rate of reabsorption increases from ~1.25%/day to ~5%/day -approximately 4× faster.
When does a pneumothorax require a chest tube vs observation?
Tension PTX → immediate needle decompression (14–16G needle, 2nd intercostal space midclavicular line) followed by chest tube. Large PTX (> 2–3 cm at apex) or symptomatic → chest tube (14–16 Fr pigtail for PSP, 24–28 Fr for traumatic/secondary). Small PTX (< 2 cm), asymptomatic, primary spontaneous → observe 3–6 hours with repeat CXR. If stable → discharge with 24–48h follow-up CXR. Secondary PTX (in COPD, ILD, CF)
What is tension pneumothorax and how do you treat it before imaging?
Tension PTX is a CLINICAL DIAGNOSIS -do NOT wait for imaging. Mechanism: one-way valve effect → air enters pleural space with each breath but can't exit → progressive pressure buildup → mediastinal shift → IVC compression → obstructive shock. Signs: severe dyspnea, tachycardia, hypotension, absent breath sounds on affected side, tracheal deviation AWAY from affected side (late sign), distended neck veins, subcutaneous emphysema.
What is the Fleischner Society recommendation for incidentally detected pneumothorax?
Trick question -Fleischner is for pulmonary nodules, not pneumothorax. This is a common confusion. For pneumothorax management: BTS guidelines are the standard. Small primary spontaneous PTX (< 2 cm at hilum) + minimal symptoms → observation + supplemental O₂ + repeat CXR in 2-4h. If stable → discharge with 24-48h follow-up. Large (> 2 cm) or symptomatic → aspiration (with small-bore catheter) or chest tube. Secondary PTX (COPD, ILD, CF)
Clinical Examples
📋 Case 1, Primary Spontaneous Pneumothorax
Patient: 24M, tall and thin (6'3", 155 lb), sudden right-sided pleuritic chest pain while at rest. SpO₂ 96%. CXR: 25% right pneumothorax. Hemodynamically stable. No underlying lung disease.
Key findings: Primary spontaneous PTX, rupture of apical subpleural blebs in a classic demographic (tall, thin, young male, smoker). No underlying lung disease. Moderate size (> 2 cm at hilum).
Management:
Needle aspiration with small-bore catheter (14-16G, 2nd ICS MCL), first-line for large primary spontaneous PTX per BTS guidelines
If aspiration successful (lung re-expands on repeat CXR): observe 4-6h → discharge with 24-48h follow-up CXR
If aspiration fails: small-bore chest tube (12-14 Fr) with Heimlich valve or underwater seal
Smoking cessation counseling (recurrence risk 30% if continues smoking vs 15% if stops)
Teaching point: Needle aspiration is first-line for primary spontaneous PTX, it's as effective as chest tube with less pain, shorter hospital stay, and fewer complications. Large-bore chest tubes are overused for simple pneumothoraces.
📋 Case 2, Secondary Pneumothorax in COPD
Patient: 68M with severe COPD (FEV1 28%). Acute worsening dyspnea. SpO₂ 82% on 2L NC (baseline 90%). CXR: left pneumothorax ~20%. HR 112, BP 108/68.
Key findings: Secondary spontaneous PTX in COPD, even a small PTX is dangerous because of minimal pulmonary reserve. BTS guidelines: ALL secondary PTX > 1 cm or symptomatic need intervention (lower threshold than primary).
Management:
Small-bore chest tube (12-14 Fr), not aspiration (higher failure rate in secondary PTX)
Connect to underwater seal with -20 cmH₂O suction
Admit to monitored bed (not discharge like primary PTX)
If persistent air leak > 5 days: thoracic surgery consult for VATS pleurodesis
Teaching point: Secondary PTX is always more dangerous than primary, the diseased lung cannot compensate. Threshold for intervention is lower (any symptomatic PTX), and these patients require admission, not outpatient management.
📋 Case 3, Recurrent Pneumothorax Requiring Pleurodesis
Patient: 28M with third right-sided spontaneous PTX in 2 years. Current episode: 35% PTX, managed with chest tube (resolved in 48h). Previous 2 episodes also required chest tubes.
Key findings: Recurrent ipsilateral PTX, after first episode, recurrence risk is ~30%. After second episode, ~50%. After third, > 80%. Definitive prevention is indicated.
Management:
VATS (video-assisted thoracoscopic surgery) with blebectomy + mechanical pleurodesis, gold standard for recurrent PTX
Alternative: chemical pleurodesis via chest tube (talc slurry) if not a surgical candidate
CT chest to assess bleb distribution before surgery
Absolute indication for pleurodesis: second ipsilateral PTX, first contralateral PTX (bilateral), occupational risk (pilots, divers)
Teaching point: Pleurodesis after second ipsilateral PTX is standard of care. VATS blebectomy + pleurodesis reduces recurrence from > 50% to < 5%. Pilots and scuba divers should have pleurodesis after FIRST episode due to occupational hazard.
📣 Sample Presentation
One-Liner
"Mr. Scott is a 22-year-old tall, thin male presenting with sudden right-sided pleuritic chest pain and dyspnea. CXR shows 30% right pneumothorax. Hemodynamically stable. SpO₂ 97%."
Key Points to Cover on Rounds
Primary spontaneous pneumothorax -classic demographics (tall, thin, young male). Large (30% at apex), symptomatic. Treatment: 14 Fr pigtail chest tube placed under US guidance, connected to water seal. Post-procedure CXR: lung re-expanded, no residual PTX. Air leak: resolved by 12h. O₂ applied (accelerates pleural nitrogen reabsorption). Plan: chest tube to water seal ×12h → if no recurrence on CXR → remove and observe ×6h → discharge if stable. Recurrence counseling: 30% chance of recurrence. If 2nd episode → VATS with pleurodesis. Avoid flying ×2 weeks, avoid scuba diving permanently.
🧪 Workup
Workup
See the Overview and Management tabs for the pneumothorax workup algorithm (CXR upright expiratory, CT chest for occult/loculated, CTA if PE suspected, ABG for oxygenation).
💊 Medications
Medications
Medication details (high-flow O₂ to accelerate air reabsorption, analgesia for chest tube, pleurodesis agents like talc/doxycycline for recurrent pneumothorax) are in the Management tab with evidence-based dosing.
⚡ Summary
Summary
Tension Is a Clinical Diagnosis
Hypotension, distended neck veins, absent breath sounds and tracheal deviation away from the affected side.Needle decompress immediately; do not wait for a chest x-ray. The film adds minutes the patient does not have, and the diagnosis is made at the bedside.
Classify It, Because Management Differs
Primary spontaneous: tall thin young male, no lung disease, from an apical bleb.Secondary spontaneous: COPD, cystic fibrosis, and far less well tolerated because reserve is already gone.Traumatic and iatrogenic, most often after central line placement, thoracentesis or biopsy. Secondary pneumothorax is managed more aggressively at any given size, because a small one can be fatal in a patient with an FEV1 of 30%.
Size and Symptoms Drive the Decision
Small (under about 2 to 3 cm), primary and asymptomatic: observation with high-flow oxygen, and repeat imaging.Large or symptomatic: needle aspiration or a small-bore chest tube.Any secondary pneumothorax, any tension, any bilateral or hemodynamically significant one: chest tube. Increasingly, conservative management is favored even for larger primary pneumothoraces in stable patients.
High-Flow Oxygen Is Therapeutic, Not Just Supportive
15 L/min by non-rebreather accelerates reabsorption roughly fourfold, from about 1.25% of the volume per day to 4 to 5%. It works by washing nitrogen out of the alveoli, creating a gradient that draws the mostly-nitrogen pleural air back into the blood. Give it even to a patient who is not hypoxemic.
Know the Clue Patterns
Tall thin young male with sudden pleuritic pain at rest: primary spontaneous.Recurrent right-sided pneumothorax in a reproductive-age woman around menses: catamenial, from thoracic endometriosis.Young woman with cystic lung disease: lymphangioleiomyomatosis.Recurrent pneumothorax with a family history: Birt-Hogg-Dube.
Place the Tube Safely
The safe triangle: lateral border of pectoralis major, anterior border of latissimus dorsi, above the level of the nipple.Insert over the top of the rib to avoid the neurovascular bundle running under it. Small-bore catheters are as effective as large-bore for most non-traumatic pneumothoraces and are far more comfortable.
Watch for Re-Expansion Pulmonary Edema
Do not drain a large or chronic pneumothorax rapidly.Re-expanding a lung that has been collapsed for more than a few days can cause unilateral pulmonary edema, so control the rate and avoid immediate suction. Manage the same risk when removing large volumes of pleural fluid.
Prevent Recurrence and Counsel
Recurrence after a first primary spontaneous pneumothorax is roughly 30%, and higher after a second.Refer for VATS with pleurodesis or bullectomy after a second ipsilateral event, a first contralateral event, persistent air leak beyond 3 to 5 days, or in high-risk occupations such as diving and flying.Smoking cessation is the highest-yield preventive measure, and patients must not fly until resolution is confirmed.
⚠️ Key distinction: If a patient has OSA + elevated daytime PaCO₂ (>45 mmHg), they have OHS until proven otherwise. CPAP alone may not be enough -they need BiPAP.
Feature
OSA
OHS
Definition
Repetitive upper airway collapse during sleep
BMI ≥30 + awake hypercapnia (PaCO₂ >45) not explained by another cause
Daytime PaCO₂
Normal
Elevated (>45 mmHg) -THE distinguishing feature
Mechanism
Mechanical pharyngeal obstruction
↓ Chest wall compliance + impaired central respiratory drive + coexisting OSA (90%)
ABG (awake)
Normal
Chronic respiratory acidosis (↑CO₂, ↑HCO₃⁻ from renal compensation)
Serum HCO₃⁻
Normal
Elevated (>27 mEq/L) -a screening clue on BMP
Sleep study
AHI ≥5 with symptoms
90% also have OSA. Key is the awake hypercapnia, not the AHI
Treatment
CPAP (splints airway open)
BiPAP with backup rate (needs inspiratory pressure support to ventilate, not just splint). Average volume-assured pressure support (AVAPS) is emerging.
Why CPAP fails in OHS
N/A -CPAP is sufficient
CPAP only holds the airway open. OHS patients also have impaired respiratory drive + restrictive physiology → need the extra pressure support of BiPAP to move air in and out
Mortality
Increased CV risk if untreated
Higher than OSA alone. 18-month mortality ~23% if untreated (vs ~9% for OSA alone)
Screening tip
STOP-BANG ≥3
Obese patient with unexplained elevated HCO₃⁻ on BMP → check ABG → if PaCO₂ >45 → OHS
🔄 Updated Practice: OHS is underdiagnosed. Many patients labeled as "OSA not responding to CPAP" actually have OHS and need BiPAP. If an obese patient has persistent hypoxemia or hypercapnia despite adequate CPAP use, check an ABG -they may need escalation to BiPAP with backup rate.
RoundsRx Licensed Content - Unauthorized Use Prohibited💊 Management
OSA patients are high-risk perioperatively. Opioids and sedatives suppress respiratory drive and pharyngeal muscle tone → upper airway collapse → hypoxia, reintubation, ICU transfer.
Bring home CPAP to hospital -use immediately postop
Why is OSA the #1 cause of resistant hypertension?
Intermittent hypoxia from apneic episodes triggers sympathetic nervous system activation (repeated fight-or-flight surges throughout the night), increases RAAS activity, causes endothelial dysfunction, and promotes systemic inflammation. These effects persist into the daytime -the BP doesn't normalize with sleep as it should (loss of nocturnal dipping).
Why is untreated OSA dangerous beyond just daytime sleepiness?
OSA is a systemic disease, not just a sleep problem. Recurrent hypoxemia and sympathetic surges during apneic episodes cause: (1) Resistant hypertension -OSA is the #1 cause of secondary HTN. CPAP reduces BP by 2–10 mmHg. (2) Atrial fibrillation -OSA increases AF risk 2–4×. Untreated OSA doubles AF recurrence after cardioversion or ablation. (3) Pulmonary hypertension -chronic hypoxic vasoconstriction → right heart failure
Why is untreated OSA a risk factor for resistant hypertension and atrial fibrillation?
Resistant HTN: During apneic episodes, hypoxemia triggers massive sympathetic surges → catecholamine release → vasoconstriction + tachycardia. Repeated nightly for years → sustained sympathetic overdrive + vascular remodeling. OSA is the #1 identifiable cause of resistant hypertension (HTN on ≥ 3 meds including a diuretic). CPAP reduces BP by 2-10 mmHg. Screen every patient with resistant HTN for OSA.Atrial fibrillation: Mechanism
What does the AHI number actually mean?
AHI (Apnea-Hypopnea Index) = number of apnea + hypopnea events per hour of sleep. Apnea: complete cessation of airflow ≥ 10 seconds. Hypopnea: ≥ 30% reduction in airflow with ≥ 3% O₂ desaturation or arousal. Severity: Mild: AHI 5-15 (may not need CPAP if asymptomatic). Moderate: AHI 15-30 (CPAP recommended). Severe: AHI > 30 (CPAP strongly recommended, significant CV risk).
Clinical Examples
📋 Case 1, Severe OSA with Resistant Hypertension
Patient: 52M, BMI 38, on amlodipine 10, lisinopril 40, chlorthalidone 25, BP still 152/94. Daytime somnolence (Epworth 18), witnessed apneas by wife, morning headaches. Sleep study: AHI 48, nadir SpO₂ 72%.
Key findings: Severe OSA (AHI > 30) causing resistant hypertension. OSA is the #1 secondary cause of resistant HTN. Nocturnal hypoxemia → sympathetic surges → sustained daytime HTN. Also increases risk of Afib, stroke, and sudden cardiac death.
Mask fitting is critical for compliance, trial nasal pillows, nasal mask, or full face mask based on preference
Weight loss counseling, 10% weight loss can reduce AHI by 26-50%
Recheck BP after 3 months of CPAP, may be able to reduce antihypertensives
Screen for metabolic syndrome, T2DM (OSA independently worsens insulin resistance)
Teaching point: CPAP reduces BP by ~3-5 mmHg on average, modest but clinically meaningful in resistant HTN. The benefit is greatest in patients who use CPAP > 4h/night. Non-compliant patients get no benefit, making adherence counseling essential.
📋 Case 2, OSA Pre-Surgical Risk
Patient: 64F, BMI 42, scheduled for elective knee replacement. STOP-BANG score 6 (high risk). Never had a sleep study. Anesthesia requesting clearance.
Key findings: High pre-test probability of OSA (STOP-BANG ≥ 5). Undiagnosed OSA increases perioperative risk: post-op respiratory depression from opioids, difficult intubation, hypoxemia, Afib, ICU admission.
Management:
Home sleep apnea test (HSAT) or in-lab polysomnography before elective surgery
If OSA confirmed: start CPAP pre-operatively (even 1-2 weeks of use reduces perioperative complications)
Anesthesia alert: potential difficult airway, have video laryngoscope available
Teaching point:STOP-BANG is the validated screening tool for OSA: Snoring, Tired, Observed apnea, Pressure (HTN), BMI > 35, Age > 50, Neck > 40 cm, Gender male. Score ≥ 5 = high probability of moderate-severe OSA.
Key findings: OHS = obesity (BMI ≥ 30) + awake daytime hypercapnia (PaCO₂ > 45) + sleep-disordered breathing, without another cause of hypoventilation. Elevated bicarb = chronic respiratory acidosis with metabolic compensation. Polycythemia from chronic hypoxia.
Management:
Bilevel PAP (BiPAP) with backup rate, preferred over CPAP in OHS (addresses both obstruction AND hypoventilation)
Supplemental O₂ titrated to SpO₂ 88-92% (avoid over-oxygenation, may worsen hypercapnia)
Weight loss: bariatric surgery referral (most effective long-term intervention for OHS)
Diuretics for right heart failure (RV volume overload from chronic pulmonary HTN)
Monitor ABGs, PaCO₂ should improve with consistent BiPAP use over weeks
Teaching point: OHS is NOT just "severe OSA." It's a distinct entity with daytime hypercapnia requiring BiPAP with backup rate (not just CPAP). Untreated OHS has 18% mortality at 18 months vs 3% with treatment. Weight loss is curative.
📣 Sample Presentation
One-Liner
"Mr. Martinez is a 48-year-old with BMI 36, resistant hypertension on 3 medications, and daytime sleepiness (Epworth 16). Sleep study: AHI 42, lowest O₂ desaturation 78%. Severe OSA."
Key Points to Cover on Rounds
Severe OSA (AHI 42). STOP-BANG score 7. Treatment: CPAP initiated -auto-titrating, pressure range 8-16 cmH₂O. Mask fitting done (nasal pillow chosen). CPAP adherence education: use ≥4h/night for ≥70% of nights. Resistant HTN: OSA is the #1 cause of secondary HTN -expect BP improvement with CPAP (2-10 mmHg reduction). Afib screening: ECG in sinus. Weight loss counseling: semaglutide discussed (dual benefit: weight + likely improves AHI). Driving safety discussed: avoid drowsy driving until treated. Plan: follow-up in 4 weeks for CPAP compliance data download, reassess BP medications.
🧪 Workup
Workup -Obstructive Sleep Apnea
Topic-specific workup details are in the Overview and Management tabs.
💊 Medications
Medications for OSA
Medication
Dose
Mechanism
Notes
Semaglutide (Wegovy) EMERGING
0.25mg SQ weekly → titrate to 2.4mg weekly
GLP-1 RA → weight loss → reduced pharyngeal fat → improved AHI
SELECT, 2023: ~20% weight loss. Dual benefit: weight + AHI reduction. Not yet FDA-approved specifically for OSA.
Tirzepatide (Mounjaro/Zepbound) EMERGING
2.5mg SQ weekly → titrate to 15mg weekly
GIP/GLP-1 dual agonist → greater weight loss → AHI improvement
SURMOUNT-OSA, 2024: Up to 62.8% reduction in AHI. May become first-line pharmacologic adjunct for obese OSA.
Modafinil (Provigil)
200mg PO daily (AM)
Wakefulness-promoting agent
For residual daytime sleepiness DESPITE adequate CPAP use. Does NOT treat the apnea itself -treats the symptom only. Not a substitute for CPAP.
Armodafinil (Nuvigil)
150mg PO daily (AM)
R-enantiomer of modafinil, longer half-life
Same indication as modafinil -residual sleepiness on CPAP. Slightly longer duration of action.
Solriamfetol (Sunosi)
75mg PO daily → max 150mg
Dopamine/norepinephrine reuptake inhibitor
FDA-approved for excessive daytime sleepiness in OSA (on CPAP). More potent wakefulness effect than modafinil. Avoid in uncontrolled HTN.
Used for central sleep apnea (CSA) and high-altitude OSA. NOT standard for typical OSA. May reduce AHI in select cases.
🔄 Updated Practice: GLP-1 receptor agonists (semaglutide, tirzepatide) are emerging as game-changers for OSA in obese patients. SURMOUNT-OSA, 2024 showed tirzepatide reduced AHI by up to 63% -potentially more effective than any prior pharmacologic therapy. While not yet first-line, expect these to become standard adjuncts to CPAP for obese OSA patients. Weight loss addresses the root cause rather than just treating symptoms.
⚠️ Medications to AVOID in OSA: Benzodiazepines, opioids, barbiturates, and sedating antihistamines suppress respiratory drive and pharyngeal muscle tone → worsen apneas → life-threatening hypoxemia. If sedation is needed, use non-benzodiazepine options and ensure continuous pulse oximetry.
⚡ Summary
Summary
Screen With STOP-BANG
Snoring, Tiredness, Observed apneas, blood Pressure, BMI above 35, Age over 50, Neck circumference above 40 cm, male Gender. A score of 3 or more is high risk and 5 or more is very high risk. It is quick and sensitive, which makes it a good preoperative and inpatient screen.
Polysomnography Diagnoses and Grades It
AHI 5 to 15 mild, 15 to 30 moderate, above 30 severe.Home sleep apnea testing is acceptable for uncomplicated high-probability patients but underestimates severity and a negative study does not exclude OSA, so significant comorbidity or a negative home test with strong symptoms warrants in-lab study.
It Is a Cardiovascular Disease
Independently associated with resistant hypertension, atrial fibrillation, heart failure, stroke and pulmonary hypertension, through intermittent hypoxia, sympathetic surges and large intrathoracic pressure swings. Treat resistant hypertension and recurrent atrial fibrillation as reasons to test for OSA, since untreated apnea drives AF recurrence after cardioversion and ablation.
Check a CO2 Before Blaming CPAP Failure
OSA with a daytime PaCO₂ above 45 mmHg is obesity hypoventilation syndrome until proven otherwise.CPAP alone may not be enough; these patients need BiPAP.OHS is widely underdiagnosed, and many patients labeled as 'OSA not responding to CPAP' actually have it, so an obese patient with persistent hypoxemia or hypercapnia despite good CPAP adherence needs a blood gas, not a higher pressure.
CPAP Works If It Is Worn
It reliably improves sleepiness, quality of life and blood pressure, particularly in symptomatic severe disease.Adherence is the limiting factor, so mask fit, humidification, desensitization and early follow-up matter more than the specific device. Large trials have not shown a clear reduction in cardiovascular events, largely because average nightly use in those trials was low.
Know the Alternatives
Mandibular advancement devices for mild to moderate disease or CPAP intolerance.Positional therapy for supine-predominant apnea.Hypoglossal nerve stimulation for selected moderate to severe patients who cannot tolerate CPAP.Weight loss is disease-modifying, and bariatric surgery or GLP-1 therapy can substantially reduce the AHI.
Take Care Around Sedation and Surgery
Opioids, benzodiazepines and general anesthesia worsen upper airway collapse and blunt the arousal response, which is why undiagnosed OSA is a major cause of perioperative respiratory complications. Screen preoperatively, bring the patient's own CPAP into hospital, and use extended monitoring after sedation.
Ask About Driving
Untreated OSA substantially increases motor vehicle accident risk.Ask directly about sleepiness while driving, counsel explicitly, and know the local reporting requirements, particularly in commercial drivers. It is the part of the consultation most often skipped and the one with the clearest public consequence.
RoundsRx Infographic Series · #127 · Respiratory · PDF 155 KB
Text version
Pulmonology / Sleep · One Pager
Obstructive Sleep Apnea
AHI ≥ 5 + symptoms or ≥ 15 regardless. CPAP is gold standard. #1 cause of resistant HTN. Doubles AF recurrence. Weight loss with GLP-1 RA is emerging adjunct.
🧪 Diagnosis
AHI ≥ 5 + symptoms (EDS, witnessed apneas, morning headache) OR AHI ≥ 15 regardless. Mild: 5-15. Moderate: 15-30. Severe: > 30. Home sleep test or in-lab PSG.
#1 cause of resistant hypertension (screen every resistant HTN patient). Doubles AF recurrence after cardioversion/ablation. Associated with: stroke, MI, HF, pulmonary HTN, sudden cardiac death.
A heterogeneous group of diseases causing inflammation and/or fibrosis of the lung parenchyma. IPF is the most common and most lethal. HRCT pattern recognition is essential -UIP vs NSIP vs organizing pneumonia drives management.
🔍 Overview
Common ILD Patterns on HRCT
HRCT Pattern
Key Features
Most Likely Diagnosis
Prognosis
UIP (Usual Interstitial Pneumonia)
Basal, peripheral, subpleural honeycombing + traction bronchiectasis + reticulation. Heterogeneous (areas of normal lung adjacent to fibrosis).
IPF (if no identifiable cause)
Worst. Median survival 3–5 years.
NSIP (Non-Specific Interstitial Pneumonia)
Ground-glass opacities, basal-predominant, relatively uniform. Subpleural sparing. Less honeycombing.
Diagnosis: UIP pattern on HRCT in appropriate clinical context → may not need biopsy. If HRCT indeterminate → surgical lung biopsy via VATS for confirmation.
IPF Antifibrotic Therapy
Drug
Dose
Evidence
Notes
Pirfenidone (Esbriet) ANTIFIBROTIC
267 mg TID → titrate to 801 mg TID
ASCEND, 2014: reduced FVC decline by ~50% at 1 year.
Slows progression, does not cure. GI side effects (nausea), photosensitivity. Take with food.
Nintedanib (Ofev) ANTIFIBROTIC
150 mg BID
INPULSIS, 2014: reduced FVC decline by ~50%. Also approved for SSc-ILD and progressive fibrosing ILD.
Tyrosine kinase inhibitor. Diarrhea is the main side effect (~60%). Hepatotoxicity -monitor LFTs.
When to Refer for Transplant
FVC decline ≥ 10% in 6 months
DLCO < 40% predicted
Desaturation < 88% on 6-minute walk test
Hospitalization for respiratory decline or pneumothorax
Refer early -transplant evaluation takes months
💊 Management
IPF -Antifibrotic Therapy
Steroids and immunosuppressants are HARMFUL in IPF.PANTHER-IPF, 2012: prednisone + azathioprine + NAC increased mortality and hospitalizations vs placebo. Stopped early for harm.
Drug
Dose
Evidence
Notes
Pirfenidone (Esbriet) ANTIFIBROTIC
267 mg TID → titrate to 801 mg TID
ASCEND, 2014: reduced FVC decline by ~50% at 1 year.
Slows progression, does not cure. GI side effects (nausea), photosensitivity. Take with food.
Nintedanib (Ofev) ANTIFIBROTIC
150 mg BID
INPULSIS, 2014: reduced FVC decline by ~50%. Also approved for SSc-ILD and progressive fibrosing ILD.
Tyrosine kinase inhibitor. Diarrhea is the main side effect (~60%). Hepatotoxicity -monitor LFTs.
When to Refer for Transplant
FVC decline ≥ 10% in 6 months
DLCO < 40% predicted
Desaturation < 88% on 6-minute walk test
Hospitalization for respiratory decline or pneumothorax
Refer early -transplant evaluation takes months
📋 On Rounds
Why are steroids harmful in IPF?
IPF is a fibrotic process, not primarily inflammatory. The pathology is aberrant wound healing -repeated epithelial injury → fibroblast proliferation → collagen deposition. Steroids suppress the immune system but don't target fibrosis. PANTHER-IPF, 2012 showed that the triple combination of prednisone + azathioprine + NAC increased mortality by 8× and hospitalizations by 4× compared to placebo.
How do you distinguish UIP from NSIP on HRCT, and why does it matter?
This is one of the most important radiographic distinctions in pulmonology because it determines treatment and prognosis. UIP (usual interstitial pneumonia) = IPF pattern: basal-predominant, peripheral honeycombing, traction bronchiectasis, minimal GGO. Prognosis: median survival 3–5 years. Treatment: antifibrotics only (nintedanib or pirfenidone) -steroids are HARMFUL. NSIP (nonspecific interstitial pneumonia)
When should you refer an ILD patient for lung transplant evaluation?
Refer early -don't wait until the patient is too sick. General criteria: (1) FVC declining > 5-10% per year despite treatment (antifibrotics for IPF, immunosuppression for NSIP/CTD-ILD), (2) DLCO < 40% predicted, (3) O₂ requirement at rest or with exertion, (4) 6-minute walk distance < 250m or declining, (5) Pulmonary hypertension (RVSP > 40 on echo).
What is the role of pulmonary rehabilitation in ILD?
Pulmonary rehab is one of the most effective interventions in ILD -yet it's dramatically underutilized. Benefits: improved exercise capacity (6MWD increases 30-50m), reduced dyspnea, improved quality of life, reduced anxiety/depression. It works even in IPF where the lung disease itself is progressive and irreversible -pulmonary rehab trains the muscles and cardiovascular system to work more efficiently with less lung function.
Clinical Examples
📋 Case 1, Idiopathic Pulmonary Fibrosis (IPF)
Patient: 72M with progressive dyspnea × 2 years and dry cough. Bibasilar velcro crackles. PFTs: FVC 58%, DLCO 42% (restrictive + impaired gas exchange). HRCT: basal-predominant honeycombing, traction bronchiectasis, minimal GGO. UIP pattern.
Key findings: Definite UIP pattern on HRCT = IPF diagnosis without biopsy needed (if clinical context fits). IPF is the most common and most lethal ILD, median survival 3-5 years from diagnosis.
Management:
Antifibrotic therapy: pirfenidone or nintedanib (slows FVC decline by ~50%) ASCEND/INPULSIS, 2014
Pulmonary rehabilitation (improves exercise capacity and QOL even as disease progresses)
Supplemental O₂ for resting SpO₂ < 88% or exertional desaturation
Lung transplant evaluation if age < 70, no major comorbidities, refer EARLY (waitlist mortality is high)
NO steroids or immunosuppression (PANTHER-IPF showed HARM from prednisone + azathioprine + NAC in IPF)
Teaching point: Steroids are HARMFUL in IPF, this is the one ILD where immunosuppression makes things worse. Antifibrotics (pirfenidone, nintedanib) slow progression but do not reverse fibrosis. Early transplant referral is critical.
📋 Case 2, Hypersensitivity Pneumonitis (Chronic)
Patient: 55F bird breeder with progressive dyspnea × 1 year. HRCT: diffuse GGO with mosaic attenuation, air trapping on expiratory images, centrilobular nodules. No honeycombing. PFTs: FVC 68%, DLCO 52%. BAL: lymphocytosis 48%.
Key findings: Chronic hypersensitivity pneumonitis from avian antigen exposure. HRCT pattern: GGO + mosaic attenuation + air trapping is classic. BAL lymphocytosis (> 30%) supports the diagnosis. Unlike IPF, HP is potentially reversible with antigen avoidance.
Management:
Antigen avoidance is the MOST important intervention, remove birds, professional home cleaning
Prednisone 0.5 mg/kg daily × 4-8 weeks for symptomatic disease, then slow taper
If fibrotic HP refractory to steroids: mycophenolate or azathioprine as steroid-sparing agents
If fibrotic HP progressing despite antigen avoidance + immunosuppression: consider antifibrotic (nintedanib approved for progressive fibrosing ILD)
Serial PFTs q3-6 months to monitor for progression vs stabilization
Teaching point: HP is the treatable mimic of IPF. The key differentiators: HP has GGO + mosaic attenuation (not honeycombing), BAL lymphocytosis, and an identifiable exposure. Antigen removal can halt or reverse disease if caught before fibrosis.
📋 Case 3, Acute Exacerbation of IPF
Patient: 68M with known IPF on nintedanib. Admitted with acute worsening dyspnea × 5 days. SpO₂ 78% on 6L NC. CT: new bilateral GGO superimposed on known UIP pattern. No PE on CTA. Sputum cultures negative.
Key findings: Acute exacerbation of IPF: rapid respiratory deterioration + new bilateral GGO on CT + no identifiable cause (ruled out infection, PE, HF). Mortality > 50% per episode.
Management:
High-dose methylprednisolone 1g IV daily × 3 days → prednisone 1 mg/kg taper (limited evidence but standard practice)
Broad-spectrum antibiotics until infection excluded (empiric coverage while cultures pending)
High-flow nasal cannula or NIV for respiratory support, intubation carries very poor prognosis in IPF
Discuss goals of care early, in-hospital mortality for intubated IPF patients exceeds 80%
Continue antifibrotic therapy if able to take PO
Teaching point: Acute exacerbation of IPF is often fatal. The most important conversation is goals of care, mechanical ventilation in IPF rarely leads to meaningful recovery. Palliative care should be involved early if the patient does not respond to steroids within 48-72h.
📣 Sample Presentation
One-Liner
"Mrs. Park is a 68-year-old non-smoker presenting with 18 months of progressive dyspnea and dry cough. HRCT shows basal-predominant honeycombing, traction bronchiectasis, and minimal GGO -UIP pattern. PFTs: FVC 62%, DLCO 48%. Consistent with IPF."
Key Points to Cover on Rounds
HRCT: definite UIP pattern (basal honeycombing, traction bronchiectasis, no GGO). PFTs: restrictive (FVC 62%), DLCO 48% (severely reduced). Autoimmune workup: ANA, RF, CCP, myositis panel -all negative (not CTD-ILD). No significant exposures (no birds, mold, medications). Diagnosis: IPF (definite UIP on imaging, exclusion of other causes -biopsy not needed). Treatment: nintedanib 150 mg BID started (antifibrotic -slows FVC decline). NOT steroids (harmful in IPF). O₂: prescribed for exertional desaturation (SpO₂ 84% on 6MWT). Pulmonary rehab referral. Transplant evaluation: referred given age and severity. Plan: PFTs q6 months, annual HRCT.
🧪 Workup
Workup
See the Overview and Management tabs for the ILD workup algorithm (HRCT pattern recognition, PFTs with DLCO, serologic panel for CTD-ILD, bronchoscopy/BAL + surgical lung biopsy when pattern is ambiguous).
💊 Medications
Medications
Medication details (antifibrotics like pirfenidone/nintedanib for IPF, corticosteroids + mycophenolate/azathioprine for CTD-ILD, specific agents by ILD subtype) are in the Management tab with evidence-based dosing and trial citations.
⚡ Summary
Summary
The HRCT Pattern Drives Management
UIP, NSIP and organizing pneumonia are the three patterns to recognize, and they lead to completely different treatments. UIP: basal and subpleural honeycombing with traction bronchiectasis, and it means IPF unless there is a secondary cause.NSIP: ground-glass with subpleural sparing, seen in connective tissue disease.Organizing pneumonia: patchy peripheral consolidation, and it responds to steroids.
Steroids Are Harmful in IPF
PANTHER-IPF was stopped early for harm: prednisone plus azathioprine plus N-acetylcysteine increased mortality and hospitalizations versus placebo.Do not treat a UIP pattern with immunosuppression. This is the single most consequential error on the page, because immunosuppression is the reflex for most other diffuse lung disease.
Antifibrotics Are the IPF Treatment
Pirfenidone and nintedanib slow the decline in FVC and are started at diagnosis, not when the patient deteriorates.They do not reverse fibrosis, so early initiation preserves function that would otherwise be lost. Nintedanib causes diarrhea and liver enzyme rise; pirfenidone causes photosensitivity, rash and GI upset.
Take a Real Exposure and Drug History
Birds, mold, hot tubs, feather bedding and occupational dusts point to hypersensitivity pneumonitis, where removing the antigen is the treatment and immunosuppression helps. Amiodarone, methotrexate, nitrofurantoin, bleomycin and checkpoint inhibitors cause drug-induced ILD.This history changes the diagnosis more often than any test, and it is routinely taken too briefly.
Screen for Connective Tissue Disease in Everyone
ILD can precede the rheumatologic diagnosis by years.Send ANA, rheumatoid factor, anti-CCP, myositis panel including anti-Jo-1 and anti-MDA5, and Scl-70, and examine for sclerodactyly, mechanic's hands, Raynaud and arthritis. CTD-ILD is treated with immunosuppression, which is the opposite of IPF.
Use a Multidisciplinary Discussion Rather Than a Biopsy Reflex
A confident radiologic UIP pattern in the right clinical context does not require surgical lung biopsy.Multidisciplinary review of clinical, radiologic and where necessary pathologic data is the diagnostic standard, and surgical biopsy carries real mortality in this population.
Treat the Progressive Fibrotic Phenotype
Non-IPF ILD that continues to progress despite appropriate therapy behaves like IPF, and nintedanib slows decline in that group too (INBUILD). Define progression objectively: falling FVC, worsening symptoms and increasing fibrosis on imaging, rather than impression.
Refer for Transplant Early and Manage the Rest
Refer at diagnosis in IPF, not when the patient is oxygen-dependent, because the waiting time and the disease trajectory are both unpredictable. Add supplemental oxygen for resting or exertional hypoxemia, pulmonary rehabilitation, vaccination and reflux treatment, screen for pulmonary hypertension, and recognize acute exacerbation of IPF, a rapid deterioration with new ground-glass and very high mortality, after excluding infection, heart failure and pulmonary embolism.
RoundsRx Infographic Series · #100 · Respiratory · PDF 152 KB
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Pulmonology · One Pager
Interstitial Lung Disease
CT pattern determines treatment: UIP/honeycombing = antifibrotics (NOT steroids). GGO/NSIP = immunosuppression. Screen all new ILD for CTD. Transplant referral early for IPF.
🧪 IPF
Definite UIP on HRCT (basal honeycombing, traction bronchiectasis, no GGO). Antifibrotics: nintedanib or pirfenidone (slow FVC decline). NO steroids [PANTHER-IPF = harm]. Transplant referral at diagnosis.
🚨 Other ILDs
NSIP: GGO-predominant, often CTD-associated. Responds to steroids + mycophenolate. COP: migratory infiltrates, responds dramatically to steroids. CTD-ILD: treat underlying autoimmune disease.
💊 Monitoring + Referral
PFTs (FVC, DLCO) q6 months. HRCT annually. 6MWT. Pulmonary rehab (improves QOL even in progressive disease). Transplant if: FVC declining > 5-10%/year, DLCO < 40%, O₂ requirement.
💊 Key Drugs
Nintedanib150 mg BID (IPF)
Pirfenidone801 mg TID (IPF)
Mycophenolate2-3g/day (NSIP/CTD-ILD)
Prednisone0.5-1 mg/kg (COP, NSIP)
⚠️ Pitfalls
Steroids for IPF (harmful -worsens outcomes [PANTHER-IPF])
Not screening for CTD (ANA, RF, CCP, myositis panel) in new ILD
Late transplant referral (IPF median survival 3-5 years)
Coughing up blood from the tracheobronchial tree. Non-massive (most cases): workup to find the cause. Massive (> 500 mL/24h or hemodynamic instability): the patient dies from asphyxiation, not exsanguination. Protect the airway first.
🔍 Overview
Classification
Category
Volume
Urgency
Non-massive (most common)
< 500 mL/24h, hemodynamically stable
Workup: CT chest, bronchoscopy if no source on CT. Outpatient if stable.
Massive
> 500 mL/24h (or > 100 mL/hr), or any amount causing hemodynamic instability or respiratory compromise [Crocco Classification, 1968
EMERGENCY. Airway protection → bronchoscopy → IR embolization or surgery.
Common Causes
Category
Examples
Airway (most common)
Bronchitis (#1 cause overall), bronchiectasis, lung cancer
Anticoagulation (unmasks underlying lesion), post-biopsy, PA catheter
🚨 Management
Massive Hemoptysis Protocol
Patients die from asphyxiation (drowning in blood), not hemorrhagic shock. Protect the airway. Identify the bleeding side. Isolate it. STEP Trial, Wand 2018
Immediate
Position bleeding side DOWN (gravity keeps blood in the affected lung, protects the good lung). Supplemental O₂. Large-bore IV × 2. Type and screen. Reverse anticoagulation if applicable. Hold antiplatelets.
Airway
If airway compromise → intubate with large ETT (≥ 8.0) to allow bronchoscopy through the tube. If bleeding side known → mainstem intubation of the NON-bleeding lung (advance ETT into the good side to isolate it). Double-lumen ETT if available (lung isolation).
Bronchoscopy
Rigid bronchoscopy preferred for massive hemoptysis (better suctioning, can tamponade with the scope). Flexible bronchoscopy for localization. Interventions: cold saline lavage, epinephrine instillation, balloon tamponade, electrocautery.
Bronchial artery embolization (BAE)
Definitive treatment for massive hemoptysis. Interventional radiology. ~90% immediate success rate. Recurrence: ~10–30% long-term. Complication: spinal cord ischemia (bronchial and spinal arteries share a common origin -artery of Adamkiewicz). Defined BAE Outcomes, Defined Mal 2010
Surgery
Last resort. Lobectomy/pneumonectomy if BAE fails, recurrent massive hemoptysis, or resectable lesion (e.g., aspergilloma, cancer). High surgical mortality in the emergent setting (~20–40%).
📋 On Rounds
Why do patients die from massive hemoptysis -hemorrhage or asphyxiation?
Asphyxiation. The total dead space of the tracheobronchial tree is only ~150 mL. A relatively small amount of blood (compared to GI bleeding) can flood both lungs and cause fatal hypoxia. The patient doesn't bleed to death -they drown in their own blood. This is why airway management (positioning, intubation, lung isolation) takes priority over volume resuscitation.
What is the most dangerous complication of bronchial artery embolization?
Spinal cord ischemia (paraplegia). The artery of Adamkiewicz (the major anterior spinal artery, typically arising from T9–T12 intercostal arteries) can share a common trunk with bronchial arteries or arise nearby. Inadvertent embolization of this artery causes anterior spinal artery syndrome → paraplegia. This occurs in ~1–5% of BAE procedures. Careful angiographic identification of spinal feeders before embolization is essential.
How do you manage massive hemoptysis in the first 5 minutes?
Massive hemoptysis (> 500 mL/24h or > 100 mL/hr) = airway emergency. The patient usually drowns before they exsanguinate. Step 1: Position the patient bleeding side DOWN (lateral decubitus -prevents blood from flooding the good lung). Step 2: Call for help -anesthesia for intubation, IR for bronchial artery embolization, pulmonology for bronchoscopy, thoracic surgery. Step 3: Intubate with a large ETT (≥ 8.0)
What is the most common cause of hemoptysis? (Hint: it's not cancer)
Acute bronchitis is the #1 cause of hemoptysis in the outpatient/ED setting -not cancer, not TB, not PE. Most hemoptysis is mild (< 30 mL) and self-limited from mucosal inflammation. However, the workup depends on risk factors: Low risk (age < 40, non-smoker, single episode, mild): CXR + symptomatic treatment, follow-up if persistent.
Clinical Examples
📋 Case 1, Massive Hemoptysis from Bronchiectasis
Patient: 58M with known bronchiectasis (chronic MAC infection). Sudden onset coughing up bright red blood, estimated 400 mL in 2 hours. HR 118, BP 100/62, SpO₂ 88% on room air.
Key findings: Massive hemoptysis (> 300 mL/24h or > 100 mL/hr). Bronchiectasis causes hypertrophied bronchial arteries prone to rupture. Life-threatening, death is from asphyxiation (drowning in blood), not exsanguination.
Management:
Bleeding lung DOWN, lateral decubitus with affected side dependent (protect the good lung)
Intubate with large-bore ETT (≥ 8.0) if unable to protect airway or maintain oxygenation
If BAE unavailable: rigid bronchoscopy for tamponade (Fogarty balloon catheter in bleeding segment)
Type and cross, resuscitate with blood products. TXA 1g IV
Teaching point: In massive hemoptysis, positioning is critical: bleeding lung DOWN prevents blood from flooding the contralateral lung. The cause of death is airway obstruction, not hemorrhagic shock, protecting the unaffected lung is the priority.
📋 Case 2, Hemoptysis in Lung Cancer
Patient: 67M, 40-pack-year smoker. Blood-streaked sputum × 3 weeks, 10 lb weight loss. CXR: right hilar mass. CT: 4 cm central RUL mass encasing bronchus.
Key findings: Central lung mass in a heavy smoker, squamous cell carcinoma until proven otherwise (central location, endobronchial involvement). Hemoptysis from tumor erosion into bronchial vessels.
Management:
CT angiography chest to assess vascular involvement and bleeding risk
Bronchoscopy: diagnostic (biopsy) + therapeutic (laser/electrocautery for endobronchial component if actively bleeding)
Interventional pulmonology for endobronchial stent if obstructing airway
Oncology: chemoradiation if locally advanced; palliative radiation for hemoptysis control
Teaching point: Hemoptysis in a smoker > 40 is lung cancer until proven otherwise. Even mild hemoptysis in a high-risk patient requires CT chest and bronchoscopy, the amount of hemoptysis does not correlate with cancer severity.
Key findings: DAH + RPGN = pulmonary-renal syndrome. c-ANCA positive → GPA (granulomatosis with polyangiitis). DAH confirmed by progressively bloodier BAL aliquots. Can also see hemosiderin-laden macrophages.
Management:
Pulse methylprednisolone 1g IV daily × 3 days
Rituximab 375 mg/m² weekly × 4 (induction for ANCA vasculitis)
Plasma exchange for severe DAH or Cr > 5.7 PEXIVAS, 2020
Supportive: intubation if respiratory failure, transfuse to Hgb > 7, avoid invasive procedures
Renal biopsy when stable (expect pauci-immune crescentic GN)
Teaching point: DAH is diagnosed by progressively bloodier BAL returns, not by hemoptysis (1/3 of DAH patients have no hemoptysis). The triad of bilateral infiltrates + dropping Hgb + rising Cr should prompt immediate evaluation for pulmonary-renal syndrome.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 58-year-old smoker presenting with 2 episodes of hemoptysis (~50 mL total). Hemodynamically stable. CT chest: 2.5 cm RUL mass with surrounding hemorrhage."
Key Points to Cover on Rounds
Non-massive hemoptysis with concerning RUL mass (likely malignancy in a smoker). Stable -not massive (<500 mL/24h). CT angiography: no active extravasation. Bronchoscopy: scheduled for tomorrow (diagnostic -BAL, brushings, biopsy + evaluate for bleeding source). If active bleeding at bronchoscopy → cold saline lavage, topical epinephrine, or bronchial blocker. Staging workup: PET-CT ordered, brain MRI. Smoking cessation counseled. Plan: bronchoscopy tomorrow for tissue diagnosis, multidisciplinary tumor board if malignancy confirmed. IR for bronchial artery embolization on standby if bleeding escalates.
🧪 Workup
Workup
See the Overview and Management tabs for the hemoptysis workup algorithm (massive vs non-massive triage, CXR → CT → bronchoscopy, and DAH evaluation).
💊 Medications
Medications
Medication details (TXA, reversal agents, antibiotics for infectious causes, cyclophosphamide/rituximab for DAH vasculitis) are in the Management tab with evidence-based dosing and trial citations.
⚡ Summary
Summary
They Die of Asphyxiation, Not Blood Loss
Even massive hemoptysis rarely causes hemorrhagic shock; patients drown in their own blood.The anatomic dead space is only about 150 mL, so a volume that would be trivial elsewhere fills the airway.Protect the airway first, identify the bleeding side, and isolate it.
Define Massive by Effect, Not Only Volume
Above about 500 mL in 24 h, or any volume causing hemodynamic instability, hypoxemia or airway compromise.A smaller volume in a patient with poor reserve is functionally massive, so treat the physiology rather than counting into a container.
Position the Bleeding Side Down
Lateral decubitus with the affected lung dependent, so gravity keeps blood out of the good lung.This is the single most useful thing that can be done before any equipment arrives, and it is frequently forgotten because it feels counterintuitive to lie a patient on the bad side.
Secure the Airway Deliberately
If intubation is needed, use a large endotracheal tube (8.0 or above) so a bronchoscope can pass.Selective mainstem intubation of the unaffected lung, or a bronchial blocker, isolates the bleeding side. Get anesthesia and interventional pulmonology involved early rather than after the first desaturation.
Bronchial Arteries Are the Source
Roughly 90% of massive hemoptysis comes from the bronchial circulation, which is systemic pressure, not the low-pressure pulmonary arteries.That is why bronchial artery embolization is the definitive intervention, with high immediate success. Surgery is reserved for embolization failure or a localized resectable lesion.
Know the Common Causes
Bronchiectasis, bronchitis, tuberculosis and other infection, malignancy, and pulmonary embolism.Also consider the pulmonary-renal syndromes, ANCA vasculitis and anti-GBM disease, where hemoptysis with a rising creatinine and an active sediment is a treatment emergency of a completely different kind.
Rule Out the Two Mimics First
Confirm it is really coming from the airway.Hematemesis is darker, acidic, with food particles and a GI history. Pseudohemoptysis from the nasopharynx or oropharynx is common and is settled by an ENT examination. Treating an upper GI bleed as hemoptysis wastes critical time.
Correct Coagulopathy and Investigate the Rest
Reverse anticoagulation, correct platelets and clotting factors, and consider tranexamic acid, including nebulized, which reduces bleeding in non-massive hemoptysis.For non-massive hemoptysis, CT is the initial test, with bronchoscopy for localization, tissue and therapeutic intervention. A normal chest x-ray does not exclude malignancy, so a smoker over 40 with hemoptysis needs a CT and usually a bronchoscopy regardless.
RoundsRx Infographic Series · #135 · Respiratory · PDF 142 KB
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Pulmonology · One Pager
Hemoptysis
Most common = bronchitis. Most dangerous = massive (> 500 mL/24h) → airway emergency. Bleeding side DOWN. Bronchoscopy + IR embolization. Always consider malignancy in smokers > 40.
AIRWAY EMERGENCY -patient drowns before exsanguinating. (1) Bleeding side DOWN. (2) Intubate (large ETT ≥ 8.0). (3) Bronchoscopy for localization. (4) IR bronchial artery embolization (definitive ~90%). (5) Surgery if refractory.
Irreversible airflow obstruction (FEV₁/FVC < 0.70 post-bronchodilator). GOLD staging drives therapy. Inhaler selection matters -know the stepwise approach. For acute exacerbations requiring ICU management, see AECOPD (ICU).
↪
Also see:AECOPD (Acute Exacerbation, ICU) for inpatient management: NIV pathway, antibiotic selection, steroid burst, vent settings.
🔍 Overview
What changed in GOLD 2026 COPD Report (released January 2026): (1)Biologics codified for severe eosinophilic COPD -mepolizumab, benralizumab (anti-IL-5/IL-5R), and dupilumab (anti-IL-4Rα) for patients with frequent exacerbations and blood eosinophils ≥ 300 cells/μL despite optimized inhaler triple therapy. (2)ABE classification (introduced 2023) refined further -A (low symptom + low exacerbation), B (high symptom + low exacerbation), E (any exacerbations regardless of symptom). Old ABCD framework retired. (3)Triple therapy (LABA/LAMA/ICS) reserved for Group E with eos ≥ 300 OR persistent exacerbations on LABA/LAMA. ICS-without-LABA is not appropriate. Step-down to LABA/LAMA encouraged when eos low and stable. (4) Spirometry severity (GOLD 1-4) retained for FEV₁ % predicted; symptoms (CAT, mMRC) and exacerbation history drive treatment, not GOLD stage alone. (5)Smoking cessation -varenicline preferred, cytisinicline now available, combination NRT (patch + short-acting) emphasized. (6)Pulmonary rehab within 4 weeks post-exacerbation strongly emphasized -reduces 1-year mortality and rehospitalization.
Symptoms: chronic dyspnea, cough, sputum production (≥ 3 months/year × 2 years = chronic bronchitis definition)
Risk factors: smoking (> 10 pack-years), alpha-1 antitrypsin deficiency (test in early-onset or non-smoker COPD), biomass fuel exposure
GOLD Severity (by FEV₁)
GOLD Stage
FEV₁ (% predicted)
Severity
GOLD 1
≥ 80%
Mild
GOLD 2
50–79%
Moderate
GOLD 3
30–49%
Severe
GOLD 4
< 30%
Very severe
GOLD Stage vs GOLD ABE -they answer two different questions. A common point of confusion. GOLD Stage 1-4 (FEV₁ % predicted) tells you how bad the airflow obstruction is -drives prognosis, LVRS / lung transplant eligibility, disability evaluations. GOLD ABE (symptoms + exacerbation history) tells you what treatment the patient needs -drives inhaler choice, biologic eligibility, post-exacerbation rehab triggers. Treatment is NOT driven by FEV₁ anymore. A patient with GOLD 1 (mild FEV₁) but frequent exacerbations is Group E and gets aggressive therapy; a patient with GOLD 4 but no exacerbations and low symptoms could be Group A on a bronchodilator alone. Rule of thumb:GOLD Stage → prognosis. GOLD ABE → inhaler.
GOLD ABE Groups (2023, refined in 2026)
The 2023 GOLD report simplified the old ABCD into ABE; the 2026 report refined the framework further (biologics codified for severe eosinophilic Group E, triple therapy step-down rules, ICS-without-LABA explicitly inappropriate). Assessment is based on symptoms + exacerbation history.
Group
Symptoms (mMRC / CAT)
Exacerbations
Initial Therapy
A
Low (mMRC 0–1, CAT < 10)
0–1 (not leading to hospitalization)
Bronchodilator (SABA PRN or LAMA or LABA)
B
High (mMRC ≥ 2, CAT ≥ 10)
0–1 (not leading to hospitalization)
LABA + LAMA combination
E (Exacerbator)
Any
≥ 2 moderate or ≥ 1 hospitalization
LABA + LAMA. Consider LABA + LAMA + ICS if eos ≥ 300.
💊 Stepwise Therapy
▶ How to Escalate COPD Therapy, Step by Step (tap to expand)
GOLD 2023-2026 framework: initial therapy is driven by the ABE group (symptoms + exacerbation history), NOT the spirometry stage (GOLD 1-4 still informs prognosis but no longer chooses the drug). The 2023 update collapsed the old C/D groups into a single E (exacerbator). Two things every COPD patient gets regardless of step: smoking cessation (the only intervention that slows FEV₁ decline and reduces mortality) and the full vaccine bundle (flu, PCV20, COVID, Tdap, RSV ≥ 60, Shingrix ≥ 50).
Step 1: Confirm diagnosis and grade severity
Check
What
Why
Confirm COPD
Post-bronchodilator FEV₁/FVC < 0.70 on spirometry
Symptoms alone misdiagnose. Pre-bronchodilator obstruction may reverse and represent asthma. Without spirometry, you'll over-treat reversible disease and under-treat fixed obstruction.
Informs prognosis and qualifies for some interventions (lung volume reduction, transplant), but does not drive initial drug choice.
Check eosinophils
Baseline CBC with diff
Eos < 100: avoid ICS (no benefit, pneumonia risk). Eos 100-299: ICS uncertain, use judgment. Eos ≥ 300: ICS is helpful, especially in exacerbators (key threshold).
Assess alpha-1 antitrypsin
Once in every COPD patient, especially < 45 yr, lower lobe disease, family history, or never-smoker
AAT deficiency is treatable with augmentation therapy. Missing it is missing a specific therapy. GOLD recommends one-time testing in every COPD diagnosis.
Step 2: Assign the ABE group
Group
Symptoms
Exacerbations in past year
Initial Maintenance
A
Low (mMRC 0-1 or CAT < 10)
0-1 moderate, no hospitalization
A bronchodilator (LAMA preferred, but any of SABA-PRN-only, LAMA, or LABA acceptable)
B
High (mMRC ≥ 2 or CAT ≥ 10)
0-1 moderate, no hospitalization
LABA + LAMA (2023 update upgraded from single bronchodilator to combined; better FEV₁ and symptoms)
E
Any
≥ 2 moderate, OR ≥ 1 hospitalization
LABA + LAMA; add ICS if eos ≥ 300 (initial triple therapy)
Symptom tools: mMRC scores dyspnea 0-4 (0 = only with strenuous exercise; 4 = too breathless to leave the house). CAT scores impact across 8 domains 0-40. Use either, not both. The point of the symptom score is to detect a B patient hiding among A patients, frequent silent under-treatment when only spirometry is checked.
Step 3: Follow up at 4-12 weeks → Review, Assess, Adjust
The GOLD cycle:
Review: symptoms (mMRC/CAT), exacerbations since last visit, inhaler technique (observed return-demonstration, ~70% of patients use them wrong), adherence.
Assess: if persistent dyspnea or exacerbations, why? Wrong device? Wrong drug? Missed comorbidity (HF, OSA, bronchiectasis)? Continued smoking?
Adjust: escalate, switch device, address comorbidity. Don't escalate without first verifying technique and adherence (the #1 reason for apparent treatment failure).
Step 4: Step up if persistent symptoms or exacerbations
Current Regimen
Problem
Step Up
LAMA or LABA monotherapy
Persistent dyspnea
LABA + LAMA (combined inhaler preferred for adherence)
LABA + LAMA
Persistent exacerbations, eos ≥ 300
Add ICS → ICS + LABA + LAMA triple (Trelegy, Breztri). IMPACT (2018) and ETHOS (2020) showed triple reduces exacerbations vs dual and ETHOS showed mortality benefit.
LABA + LAMA
Persistent exacerbations, eos < 100
Add roflumilast (PDE4 inhibitor) for chronic bronchitis phenotype with FEV₁ < 50%, or azithromycin 250 mg daily or 500 mg 3×/wk for ex-smokers. ICS unlikely to help here.
Triple therapy
Persistent exacerbations, eos ≥ 300
Add biologic (see Step 5)
Triple therapy
Persistent exacerbations, eos < 100, chronic bronchitis
Add roflumilast 500 mcg daily (REACT/RE2SPOND: ~17% exacerbation reduction). GI side effects rate-limit.
Triple therapy
Persistent exacerbations, frequent infections
Azithromycin 250 mg daily or 500 mg M/W/F. Check QTc and audiogram first (QT prolongation, ototoxicity). Most benefit in ex-smokers.
Step 5: Biologic add-on for severe eosinophilic COPD (GOLD 2026)
Eligibility: severe eosinophilic COPD with frequent exacerbations (≥ 2 mod or ≥ 1 hospitalization in past year) AND blood eosinophils ≥ 300 cells/μL despite optimized triple therapy. GOLD 2026 codified this pathway after BOREAS (2023) and NOTUS (2024).
Dupilumab (Dupixent) 300 mg SC q2 wk - IL-4Rα; preferred if elevated FeNO or atopy overlap.
Step 6: Non-pharm interventions, layered at every step
Intervention
When
Why
Smoking cessation
Every visit, every active smoker
The only intervention that slows FEV₁ decline and reduces mortality. Combine pharmacotherapy (varenicline or NRT) with counseling.
Pulmonary rehab
Symptomatic patients (mMRC ≥ 2), and ALL within 4 weeks of an exacerbation hospitalization
Reduces hospital readmission ~30%, improves exercise tolerance, dyspnea, QOL. Single highest-yield non-pharm intervention after smoking cessation.
Long-term oxygen therapy
Resting PaO₂ ≤ 55 or SpO₂ ≤ 88%, OR PaO₂ 56-59 with cor pulmonale, polycythemia (Hct > 55%), or peripheral edema. ≥ 15 hr/day.
NOTT (1980): > 15 hr/day O₂ reduced mortality. Not for isolated nocturnal or exercise desaturation (LOTT 2016 showed no benefit there).
Home NIV (BiPAP)
Stable severe hypercapnic COPD (PaCO₂ ≥ 52) with nocturnal hypoventilation or recent post-exacerbation hospitalization
HOT-HMV (2017): home NIV reduced readmission/death 17% in post-exacerbation hypercapnic patients.
Lung volume reduction (surgical or endoscopic valves)
Severe upper-lobe-predominant emphysema with hyperinflation and low exercise tolerance despite GDMT
NETT (2003): surgery improved exercise capacity and survival in upper-lobe-predominant, low-exercise-capacity subset. Endoscopic valves (Zephyr) approved 2018 for selected patients.
ASTHMA-COPD overlap (history of asthma, atopy, eos high, reversible component on spirometry)
ICS-containing regimen from the start (ICS+LABA, escalate to triple as needed)
ICS-naive treatment is dangerous in asthma. Treat as asthma overlap when in doubt; don't withhold ICS waiting for exacerbation history.
Frequent pneumonia on ICS
Step down to LABA + LAMA (drop the ICS), especially if eos < 100
TORCH and FLAME: ICS modestly raises pneumonia risk. If eos doesn't support ICS and patient gets pneumonia repeatedly, withdraw it. SUNSET (2018) showed safe ICS withdrawal in non-eos patients.
Persistent symptoms on optimized triple, eos < 100
Add oral steroid burst (prednisone 40 mg × 5 days, REDUCE 2013), antibiotic if increased purulence or hospitalized, increase short-acting bronchodilators. See COPD Exacerbation.
Acute management is separate from chronic escalation. After resolution, reassess group and consider step up.
Hypercapnic respiratory failure (pH < 7.35)
BiPAP first, intubate only if NIV fails or contraindicated
Brochard 1995: NIV reduces intubation 65%. Hypoxic drive concerns are overblown, target SpO₂ 88-92% to avoid hyperoxic CO₂ retention without underventilating.
Alpha-1 antitrypsin deficiency
Standard COPD therapy PLUS IV augmentation therapy (Prolastin, Zemaira) if ZZ phenotype with COPD
Disease-modifying for AAT, slows FEV₁ decline. Refer to specialty center.
End-of-life / palliative phase
Add low-dose opioids for dyspnea, anxiolytics for air hunger, palliative care referral
Morphine 1-2 mg PO q4h PRN provides dyspnea relief without respiratory depression at low dose. Pulm rehab + GDMT only goes so far in end-stage disease.
Inhaler Therapy
Drug Class
Examples
When
Key Notes
SABA PRN RESCUE
Albuterol (ProAir/Ventolin) 2 puffs q4–6h PRN
All patients -rescue inhaler
Quick onset (5–15 min). If using > 2×/week → step up maintenance therapy.
LAMA 1ST LINE MAINTENANCE
Tiotropium (Spiriva) 18 mcg daily Umeclidinium (Incruse) 62.5 mcg daily
Group A (monotherapy) or as part of combination
Preferred first-line maintenance in COPD (unlike asthma where ICS is first). Reduces exacerbations. Once-daily dosing.
LABA 1ST LINE MAINTENANCE
Salmeterol (Serevent) 50 mcg BID Formoterol 12 mcg BID Indacaterol (Arcapta) 75 mcg daily
Monotherapy or combination
Long-acting bronchodilator. Never use LABA alone in asthma (but OK in COPD).
Group E with eos ≥ 300 or persistent exacerbations on dual
IMPACT, 2018: triple reduced exacerbations by 15% vs LAMA+LABA and 25% vs ICS+LABA. ETHOS, 2020: also showed mortality reduction. Best evidence for triple in high-eos exacerbators.
Severe eosinophilic COPD with frequent exacerbations AND blood eos ≥ 300 cells/μL despite optimized triple therapy
GOLD 2026 codified biologic add-on for severe eos COPD. Mepolizumab and benralizumab target IL-5 / IL-5R; dupilumab targets IL-4Rα (used in eos COPD with elevated FeNO or atopy overlap). BOREAS, 2023 · NOTUS, 2024 · MATINEE, 2024. Expensive ($30-40k/yr) -prior auth required.
Vaccinations -All COPD Patients
Influenza -annually
Pneumococcal -PCV20 (Prevnar 20) or PCV15 + PPSV23
COVID-19 -per current guidelines
Tdap -if not previously received, then Td booster q10y
RSV -for adults ≥ 60 (shared clinical decision)
Zoster (Shingrix) -if ≥ 50
📋 On Rounds
Why is ICS not first-line in COPD the way it is in asthma?
COPD inflammation is primarily neutrophilic (driven by CD8+ T cells, neutrophils, macrophages) and relatively steroid-resistant. Asthma inflammation is eosinophilic (Th2-driven, mast cells, eosinophils) and highly steroid-responsive. ICS in COPD adds modest exacerbation reduction but significantly increases pneumonia riskTORCH, 2007.
When do you prescribe home oxygen in COPD?
Only for severe resting hypoxemia: PaO₂ ≤ 55 mmHg or SpO₂ ≤ 88% at rest on room air (or PaO₂ 56–59 with evidence of cor pulmonale or polycythemia). Must be measured when clinically stable, at rest, on room air.NOTT, 1980 showed mortality benefit for continuous O₂ (> 15 h/day).
What changed from GOLD ABCD to ABE?
The 2023 GOLD update merged groups C and D into a single group E (Exacerbator). Previously, C = low symptoms + frequent exacerbations, D = high symptoms + frequent exacerbations -but they had the same initial treatment (LABA+LAMA ± ICS), so the distinction was clinically unnecessary. Now: A = low symptoms/low exacerbations, B = high symptoms/low exacerbations, E = any symptoms with ≥ 2 moderate or ≥ 1 hospitalized exacerbation.
When do you prescribe long-term oxygen therapy (LTOT) in COPD and what's the evidence?
Indications for LTOT (≥ 15h/day): (1) Resting PaO₂ ≤ 55 mmHg or SpO₂ ≤ 88%, (2) PaO₂ 56-59 with evidence of cor pulmonale, polycythemia (Hct > 55%), or RHF. Evidence:NOTT, 1980 and MRC, 1981 showed LTOT ≥ 15h/day reduces mortality in COPD with severe resting hypoxemia. Continuous O₂ (> 18h/day) was better than nocturnal-only.
Case 1: GOLD Group E Frequent Exacerbator
67M with COPD, 3 exacerbations in the past year (Group E), FEV₁ 45% (GOLD 3), blood eosinophils 320 cells/μL, currently on Tiotropium (Spiriva) monotherapy. Presents for optimization. Step up to triple therapy:Fluticasone furoate/Umeclidinium/Vilanterol (Trelegy Ellipta), eosinophils ≥ 300 supports ICS addition per GOLD 2023. Add Roflumilast (Daliresp) 500 mcg daily given FEV₁ < 50% + chronic bronchitis (reduces exacerbations by 15–20%). Refer to pulmonary rehab. Continue Albuterol PRN rescue. Reassess eosinophils and PFTs in 3 months.
Case 2: Stable COPD with Dyspnea, Undertreated
72F with known COPD, GOLD Group B (FEV₁ 55%, mMRC 2, CAT score 14), using only Albuterol (ProAir) PRN. No hospitalizations. Dyspnea limits daily activities. Initiate LABA/LAMA combination:Umeclidinium/Vilanterol (Anoro Ellipta) once daily, dual bronchodilation is the backbone for Group B with high symptom burden. Assess and correct inhaler technique at every visit (70–80% use inhalers incorrectly). Check SpO₂ at rest; if ≤ 88%, initiate supplemental O₂ ≥ 15h/day. Reinforce smoking cessation and ensure vaccinations (PCV20, influenza, RSV, COVID-19) are current.
Case 3: COPD-Asthma Overlap (ACO)
58M, 30 pack-year smoking history, childhood asthma diagnosis, now with fixed airflow obstruction on PFTs but partial reversibility (post-BD FEV₁ improves > 12% and 200 mL). Blood eosinophils 450 cells/μL. ICS-containing regimen is mandatory, never LABA monotherapy in ACO (asthmatic component → LABA alone increases mortality per SMART trial). Start triple therapy: Budesonide/Glycopyrrolate/Formoterol (Breztri Aerosphere). If eosinophilic disease remains uncontrolled despite maximum inhaled therapy, consider add-on biologic: Dupilumab (Dupixent) targets IL-4/IL-13 and has FDA approval for uncontrolled COPD with eosinophilic phenotype.
📣 Sample Presentation
One-Liner
"Mr. Williams is a 66-year-old with COPD (GOLD stage II, FEV₁ 62%, Group E -2 exacerbations last year), currently on tiotropium only. Here for medication optimization."
Key Points to Cover on Rounds
COPD GOLD II, Group E (≥2 exacerbations/year). Current: LAMA only (tiotropium). Undertreated. Recommended per GOLD 2024: escalate to triple therapy (LAMA + LABA + ICS) given eosinophils 320 (>300 supports ICS). Prescription: fluticasone furoate/umeclidinium/vilanterol (Trelegy) 100/62.5/25 one puff daily. Rescue: albuterol PRN. Azithromycin 250 mg MWF for exacerbation prevention (eosinophils >100 + frequent exacerbations). Vaccinations: pneumococcal (PCV20), flu, COVID, RSV -all updated. Pulmonary rehab: referred. Smoking: quit 3 years ago -reinforced. LDCT screening: current. Plan: PFTs in 3 months, reassess.
🧪 Workup
Workup -COPD
Topic-specific workup details are in the Overview and Management tabs.
💊 Medications
Medications -COPD
Medication details are in the Management tab with evidence-based dosing and trial citations.
⚡ Summary
Summary
Confirm the Diagnosis Spirometrically
Post-bronchodilator FEV1/FVC below 0.70 is required.A clinical diagnosis without spirometry is wrong roughly a third of the time, in both directions, and it commits patients to inhalers they may not need or misses asthma that would respond differently. GOLD 1 to 4 grades severity by FEV1.
Assign the ABE Group, Because It Sets the Therapy
Group A: few symptoms, no exacerbations. Group B: more symptoms, no exacerbations. Group E: any exacerbation history, 2 or more moderate or 1 requiring admission.The 2023 revision merged the old C and D into E, recognizing that exacerbation history dominates the treatment decision regardless of symptom burden.
Match the Inhaler to the Group
Group A: a bronchodilator.Group B: LABA plus LAMA combination, which beats either alone. Group E: LABA plus LAMA, adding an inhaled steroid when the blood eosinophil count is 300 cells/microlitre or more.The eosinophil count, not the symptom score, is what predicts inhaled steroid benefit.
Inhaled Steroids Are Not for Everyone
They increase pneumonia risk and, with eosinophils below 100, provide little benefit.Withdraw them in a patient with low eosinophils and no exacerbations. This is the opposite of asthma practice and it is where COPD prescribing most often drifts.
Check Inhaler Technique at Every Visit
A large proportion of patients use their device incorrectly, so what looks like treatment failure is frequently delivery failure. Check technique before escalating therapy, and match the device to the patient's inspiratory flow and dexterity rather than to habit.
The Non-Pharmacologic Interventions Are the Ones That Change Mortality
Smoking cessation is the only intervention proven to slow the decline in FEV1.Long-term oxygen therapy improves survival in resting hypoxemia, PaO2 55 mmHg or below, or 59 or below with cor pulmonale or polycythemia. Pulmonary rehabilitation improves symptoms, exercise capacity and quality of life more than any inhaler, and it is chronically under-referred.
Vaccinate Everyone
Influenza annually, pneumococcal, COVID-19, RSV in older adults, and Tdap. Vaccination reduces exacerbations, which is what drives lung function decline, hospitalization and death in this disease.
Know What to Add in Severe Disease
Roflumilast for chronic bronchitis with an FEV1 below 50% and frequent exacerbations. Azithromycin for frequent exacerbations, checking QTc and hearing. Dupilumab as a biologic add-on for severe eosinophilic COPD (GOLD 2026). Consider lung volume reduction or transplant referral in the right anatomy, screen for alpha-1 antitrypsin deficiency at least once, and introduce advance care planning early, since COPD trajectories are hard to predict.
RoundsRx Infographic Series · #126 · Respiratory · PDF 146 KB
Text version
Pulmonology · One Pager
COPD
GOLD staging by FEV₁ + symptoms + exacerbations. Triple therapy (ICS/LABA/LAMA) for Group E. LTOT if SpO₂ ≤ 88%. Pulmonary rehab reduces hospitalizations. Vaccinations for all.
🧪 Classification
Spirometry: GOLD I-IV by FEV₁ %. Group A: few symptoms, 0-1 exacerbations. Group B: more symptoms, 0-1 exacerbations. Group E: ≥ 2 exacerbations/year or ≥ 1 hospitalization.
🚨 Acute Exacerbation
Prednisone 40 mg × 5 days + antibiotics (azithromycin or doxycycline if purulent sputum) + bronchodilators + O₂ target 88-92% (avoid O₂-induced hypercapnia). BiPAP for hypercapnic respiratory failure.
💊 Chronic Management
Group A: SABA PRN. Group B: LABA or LAMA. Group E: LAMA + LABA + ICS (triple, if eos ≥ 300). Azithromycin 250 MWF (exacerbation prevention). LTOT if SpO₂ ≤ 88% [NOTT, MRC]. Pulmonary rehab. Vaccinations.
💊 Key Drugs
Trelegy ElliptaICS/LAMA/LABA (triple)
Tiotropium18 mcg daily (LAMA)
Prednisone40 mg × 5d (exacerbation)
Azithromycin250 mg MWF (prevention)
⚠️ Pitfalls
O₂ target > 92% in COPD (risk of hypercapnia -target 88-92%)
ICS without LABA (ICS monotherapy not recommended in COPD)
Missing OSA overlap (common, worsens outcomes)
Not referring for pulmonary rehab (most effective non-pharmacologic intervention)
Reversible airway obstruction with eosinophilic inflammation and bronchial hyperresponsiveness. Chronic management is stepwise ICS-based. Acute exacerbations can kill -the "quiet chest" is the most dangerous sign.
🚨 Acute Exacerbation
Severity Grading
Severity
Features
PEF
SpO₂ on RA
Disposition
Mild–Moderate
Speaks in sentences, RR < 30, HR < 120, alert
> 50% predicted
> 92%
ED treat & reassess; discharge if responsive
Severe
Speaks in phrases or words, accessory muscle use, RR > 30, HR > 120, agitated, pulsus paradoxus > 25 mmHg (tracks airflow obstruction severity; falls with improvement)
"Quiet chest" is the most dangerous sign, no air movement = no wheeze. Rising PaCO₂ on a tiring asthmatic is impending arrest, not a relief.
Don't Confuse the Protocol with AECOPD
⚠️ Same drugs, different protocol. Treating an AECOPD patient like an asthmatic (q20 min × 3 albuterol + 100% O₂) induces hypercapnia and hypoxic-drive crash. The first three decisions diverge:
Decision
Acute asthma
AECOPD
Albuterol frequency
q20 min × 3 in first hour, front-loaded
q1–4 h scheduled, no q20 min loading
Continuous nebs (albuterol)
Yes for severe (albuterol 10–15 mg/hr via large-volume nebulizer)
Rarely; intermittent dosing works and chronic patients don't tolerate continuous
Ipratropium duration
First 3 nebs only (ceiling effect, Rodrigo 2005)
Continued throughout admission (often DuoNeb q4–6 h)
YES if Anthonisen ≥ 2 of 3 (↑ dyspnea, sputum volume, sputum purulence)
NIV
Bridge only, low threshold to intubate
First-line for hypercapnic exacerbation (strong evidence; 65% relative reduction in intubation, 46% reduction in mortality per Cochrane meta-analysis, Osadnik 2017)
IV magnesium
2 g IV over 20 min for severe (per 3Mg, 2013)
Not standard, weak evidence
Decompensation tempo
Hours
Days
What's the same: dose per neb (albuterol 2.5–5 mg, ipratropium 0.5 mg), DuoNeb formulation, steroid burst with no taper if ≤ 5 days, sit upright. Full AECOPD protocol →
Acute Treatment Protocol
First 5 min
Assess & stabilize. ABCs, SpO₂, ECG, IV access, peak flow if able. Apply O₂ to keep SpO₂ 93–95% (avoid hyperoxia, target is 93–95% per BTS). Sit upright. Continuous monitoring.
First hour (SABA × the whole hour)
Albuterol 2.5–5 mg nebulized q20 min throughout the first hour (3 back-to-back doses minimum; can keep stacking q20 min while assessing response).
For severe / poor response, switch to continuous nebulization 10–15 mg/hr via large-volume nebulizer, can run uninterrupted for an hour or more.
Ipratropium 0.5 mg added to first 3 nebs only, no added benefit beyond that Rodrigo, 2005.
Systemic corticosteroids early (4–6h to take effect): prednisone 40–60 mg PO ormethylprednisolone 60–125 mg IV. PO and IV equivalent if patient tolerating PO Rowe, 2001.
Reassess at 60 min: PEF, accessory muscle use, ability to speak. SABA continues throughout, the q20 min schedule is the floor, not the ceiling.
1 hour: severe / no response
Magnesium sulfate 2 g IV over 20 min (smooth muscle relaxation, reduced admissions in severe exacerbations) 3Mg, 2013. Watch out for: some EMR order sets default to a 30–60 min infusion, change the rate to 20 min (the 3Mg trial protocol).
Epinephrine 0.3–0.5 mg IM (1:1000) if anaphylactic component, peri-arrest, or unable to deliver inhaled bronchodilator effectively (silent chest).
Trial of NIV (BiPAP): start IPAP 10–12 / EPAP 4–5, titrate IPAP up by 2 q5–10 min (typical target 15–20) to RR < 25 and accessory muscle relief. Reassess at 1–2 h. Worsening pH, rising PaCO₂, drowsiness, or no clinical improvement = intubate, do NOT persist.
Refractory / ICU
IV terbutaline (selective β₂): 0.25 mg SQ q20 min × 3, OR IV load 10 mcg/kg over 10 min → 0.4–6 mcg/kg/min infusion. Watch for tachyarrhythmia, hyperglycemia, lactic acidosis (β₂-driven, do NOT mistake for sepsis).
Ketamine for refractory bronchospasm: 0.5–1 mg/kg IV bolus, then 0.5–2 mg/kg/hr infusion. Direct bronchodilator + dissociative sedation. Bridge to intubation or buy time on NIV.Goyal, 2013 (review)
Heliox 70:30 or 80:20 helium:O₂. Lower density gas = lower turbulent flow = less work of breathing. Useful as a bridge; FiO₂ ceiling is the trade-off (cannot use if SpO₂ requirement > 30%).
Avoid: sedatives without airway control (worsens hypercapnia), aminophylline (no benefit, more toxicity), high-dose beta-blockers, NSAIDs in aspirin-sensitive asthma.
Drug Side Effects to Anticipate
Drug
Common (most patients)
Watch for / cautions
Albuterol (SABA)
Tachycardia, fine tremor, anxiety
Hypokalemia (β₂ shifts K⁺ into cells, repeat BMP after continuous nebs), lactic acidosis (β₂-driven type B, do NOT mistake for sepsis), hyperglycemia, QT prolongation at high cumulative doses, paradoxical bronchospasm (rare).
Ipratropium
Dry mouth, metallic taste
Mydriasis / acute angle-closure glaucoma if mask leaks into eye (use mouthpiece or seal mask). Urinary retention in elderly men with BPH. Avoid in true peanut/soy allergy (older formulations).
Anticipate insulin needs in diabetics (BG often jumps 100–200 within 24 h). Steroid psychosis at high doses or in elderly. HTN, fluid retention. GI upset (consider PPI if high-risk). No taper needed for ≤ 5 days.
Magnesium sulfate IV
Flushing, warmth, mild nausea
Hypotension with rapid infusion (the main reason for 20–60 min run-time). Diminished deep tendon reflexes at level > 4 mEq/L; respiratory depression / arrhythmia at > 8–10. Reduce dose in renal failure (accumulates, monitor reflexes).
Arrhythmia and ischemia risk in elderly / CAD, but life-threatening asthma overrides relative contraindications. IM (not IV) for asthma; IV epi is for arrest only. Avoid mixing with beta-blocker on board if alternatives exist (unopposed alpha can spike BP).
IV / SQ Terbutaline
Tachycardia, tremor, palpitations
Tachyarrhythmias (continuous tele required), hypokalemia, lactic acidosis (β₂-driven), hyperglycemia, myocardial ischemia in CAD. Check ECG and electrolytes q2–4h on infusion.
Laryngospasm (rare but dangerous in asthma, paradoxical airway compromise). Co-administer glycopyrrolate 0.2 mg IV to dry secretions. Emergence reactions on awakening (treat with low-dose midazolam). Theoretical ICP concern in TBI but not a contraindication in modern practice.
Heliox
None directly (inert gas)
FiO₂ ceiling: ratio is fixed (70:30 or 80:20), so cannot use if patient needs more O₂ than that delivers. Voice changes (Donald Duck effect) is harmless but disconcerting. Bridge only, does not treat the underlying obstruction.
Two electrolyte traps with high-dose β₂ therapy (continuous albuterol, IV terbutaline, or both):
(1) Hypokalemia. β₂ activation drives Na/K-ATPase, shifting K⁺ into cells. Can drop serum K⁺ by 0.5–1 mEq/L within hours. Repeat BMP and replace.
(2) Type B lactic acidosis (β₂-driven). Mechanism: β₂ stimulation → ↑ adenylyl cyclase → ↑ intracellular cAMP → activates glycogenolysis (liver, muscle) and glycolysis → pyruvate generated faster than mitochondria can oxidize it → excess pyruvate is shunted to lactate via LDH. Also ↑ lipolysis adds to the metabolic load. This is aerobic glycolysis, NOT tissue hypoxia, so the lactate is not a marker of hypoperfusion. Increased work of breathing in severe asthma adds a smaller contribution from respiratory muscle lactate. Lewis 1986; Manthous 2001
Lactate often climbs to 4–8 mmol/L on continuous β₂ therapy. Do NOT chase it with fluids, broad-spectrum antibiotics, or pressors. It resolves over hours as the β₂ drip comes down. The diagnostic clue: lactate rises while the patient is otherwise improving (better PEF, dropping HR, normalizing BP).
Intubation in Status Asthmaticus
⚠️ Indications
Cardiac or respiratory arrest
Decreased level of consciousness, exhaustion, inability to maintain effort
Rising PaCO₂ despite maximal therapy and NIV trial (not the absolute number, but the trend)
Refractory hypoxia (SpO₂ < 90% on max O₂ + NIV)
Hemodynamic instability not responding to fluids
Step
Choice
Why
Pre-oxygenate
NRB + nasal cannula 15 L apneic O₂
Asthmatics desat fast, FRC is shrunken with air trapping. HFNC if available.
Resuscitate before intubate
500–1000 mL NS bolus, push-dose epi/phenylephrine ready
Positive-pressure ventilation drops preload severely in air-trapped patients. Pre-empt hypotension.
Induction
Ketamine 1.5–2 mg/kg IV
Drug of choice. Bronchodilator, preserves BP, dissociative. Avoid propofol (drops BP) and etomidate (no bronchodilation).
Paralytic
Rocuronium 1.2 mg/kg IV
Avoid succinylcholine if hyperK risk (severe acidosis can shift K⁺ up). Rocuronium reversible with sugammadex.
Tube size
Largest that fits (8.0–9.0 in adults)
Reduces airway resistance and allows bronchoscopy / pulmonary toilet.
The killer is dynamic hyperinflation (breath stacking → auto-PEEP). Each breath adds to trapped volume because expiration is incomplete. Auto-PEEP raises intrathoracic pressure, drops venous return, and causes PEA arrest within minutes of intubation. Goal: let air out before pushing more air in.
Setting
Target
Why
Mode
Volume control (AC/VC)
Predictable Vt, lets you measure plateau and auto-PEEP precisely.
Tidal volume
6–8 mL/kg PBW
Smaller Vt = less hyperinflation. Don't try to "blow off" CO₂ with bigger breaths.
Respiratory rate
6–10 breaths/min
Long expiratory time. Slow rate is the single most important setting.
I:E ratio
1:4 to 1:5
Inspiratory time 0.8–1.0 s, leave the rest for exhalation.
Inspiratory flow
80–100 L/min (high)
Deliver Vt fast so most of cycle is exhalation.
PEEP
0–5 cm H₂O (low or zero)
Adding extrinsic PEEP can worsen hyperinflation. Some titrate to ~80% of measured auto-PEEP if patient is triggering.
Plateau pressure
< 30 cm H₂O
Reflects alveolar pressure; high plateau = barotrauma + hypotension risk. Peak pressure can be high (resistance) and that's OK if plateau is fine.
pH / PaCO₂
Accept pH ≥ 7.15–7.20, any PaCO₂
Permissive hypercapnia. Don't chase normocarbia, that's how you kill the patient.
Sedation
Deep + paralytic if needed
Ventilator dyssynchrony in asthma is fatal. Continue inhaled bronchodilators in-line with circuit.
Sudden post-intubation hypotension → think auto-PEEP first.Disconnect from vent for 30–60 seconds and let the lungs deflate, BP usually recovers within seconds. If not: tension pneumothorax (needle decompression), or acidosis-driven cardiovascular collapse (bicarb, fluids, epi).
Disposition
Discharge if: PEF > 70% predicted, symptom improvement, can speak in full sentences, SpO₂ > 94% on RA. Send with: prednisone 40 mg × 5 days (no taper needed for ≤ 5 days), albuterol PRN, step up controller if needed.
Admit if: PEF < 50% after treatment, persistent hypoxia, unable to speak in sentences, prior near-fatal asthma, high-risk features.
💊 Chronic Stepwise Therapy (GINA 2023)
▶ How to Escalate Asthma Therapy, Step by Step (tap to expand)
GINA 2023 paradigm shift:SABA-only is no longer recommended at any severity. Every asthmatic gets ICS-containing therapy from Step 1, either as-needed ICS-formoterol (Track 1, preferred) or daily low-dose ICS + SABA rescue (Track 2). SABA monotherapy raises mortality (SMART, AUSTRI signals on SABA overuse). Always reinforce non-pharm: trigger avoidance, vaccines (flu, pneumococcal, COVID), smoking cessation, weight loss if BMI > 30 (improves control), allergen immunotherapy in appropriate phenotypes.
Step 1: Confirm diagnosis and assess control
Check
What
Why
Confirm asthma
Spirometry: FEV₁/FVC < 0.70 + reversibility ≥ 12% AND 200 mL post-bronchodilator. If normal PFTs but symptoms classic: methacholine challenge (PC₂₀ < 8 mg/mL).
Symptoms alone overcall asthma. Without objective reversibility, you're treating an unproven diagnosis. Vocal cord dysfunction, GERD, post-viral cough mimic asthma and won't respond.
Assess control
Daytime symptoms > 2×/wk, nocturnal awakening, rescue use > 2×/wk, activity limitation → uncontrolled if any present
Drives initial step selection. ACT (Asthma Control Test) ≥ 20 = well-controlled, 16-19 = not well, ≤ 15 = very poor.
Check phenotype markers
Blood eos, total IgE, FeNO; consider allergy testing
Drives biologic choice if Step 5 is needed later. Get this baseline now, easier than retrospectively after starting OCS.
Step 2: Initiate by GINA step (Track 1 preferred)
GINA Step
Track 1 (Preferred)
Track 2 (Alternative)
When
Step 1
As-needed low-dose ICS-formoterol
Low-dose ICS whenever SABA used
Mild intermittent (symptoms < 2×/month, no risk factors). SYGMA (2018): PRN budesonide-formoterol reduced severe exacerbations 64% vs SABA alone.
Step 2
As-needed low-dose ICS-formoterol
Daily low-dose ICS + SABA PRN
Mild persistent (symptoms ≥ 2×/wk or any nocturnal). START (2003): early ICS reduced severe exacerbations 44% over 3 years.
Moderate. MART is one inhaler for both daily controller and rescue, reduces severe exacerbations vs separate inhalers. The patient self-titrates extra puffs when symptomatic; the ICS dose scales with need.
Step 4
Medium-dose ICS-formoterol maintenance + reliever
Medium/high-dose ICS-LABA + SABA PRN, ± LAMA
Moderate-severe. Add LAMA (tiotropium 2.5 mcg daily) if still uncontrolled. CAPTAIN (2020), TRIMARAN/TRIGGER (2019): single-inhaler triple beats ICS-LABA on exacerbations.
Step 5
Refer to specialist. High-dose ICS-LABA + LAMA. Phenotype-driven biologic. Low-dose OCS only as last resort.
Severe. See Step 5 details below for biologic selection.
Step 3: Before escalating, check the 4 T's
Most "uncontrolled" asthma is one of these, not true treatment failure. Escalating an undertreated foundation wastes drug and money.
Technique: watch them use the inhaler (return-demonstration). > 50% of patients do it wrong (poor inhalation timing, no breath-hold, propellant in the mouth not the lungs). Spacer fixes a lot.
Adherence: refill history, pharmacy data, candid "how often do you skip?" Self-report is unreliable; pharmacy refill is the truth.
Recheck control (ACT, peak flow log, rescue use, exacerbations) every 4-6 weeks until controlled, then q3-6 months. Once stable for ≥ 3 months, step DOWN by one step (smallest effective regimen reduces side effects, cost, and adherence burden). Never stop ICS entirely in moderate-severe asthma, exacerbation risk rebounds within weeks.
Step 5: Severe asthma at Step 5 → phenotype-driven biologic
Biologic is preferred over chronic OCS when patient needs ≥ 2 OCS bursts/year or daily OCS. Long-term OCS causes osteoporosis, cataracts, DM, adrenal suppression, hypertension, weight gain, infection; biologics avoid all of that. All biologics need prior auth and are expensive ($30-50k/yr).
Biologic
Target
Best For (Phenotype)
Dose
Omalizumab (Xolair)
IgE
Allergic asthma: IgE 30-1500 IU/mL, perennial allergen sensitization, eos any level
SC q2-4 wk based on weight + IgE
Mepolizumab (Nucala)
IL-5
Eosinophilic asthma: eos ≥ 150 cells/μL on current treatment (or ≥ 300 in past year), ≥ 2 exacerbations/yr
100 mg SC q4 wk
Benralizumab (Fasenra)
IL-5Rα
Same as mepolizumab; q8 wk dosing advantage
30 mg SC q4 wk × 3, then q8 wk
Dupilumab (Dupixent)
IL-4Rα (IL-4 + IL-13)
Eos ≥ 150 OR FeNO ≥ 20, also helpful with comorbid nasal polyps, atopic dermatitis, eosinophilic esophagitis
400 mg SC load, then 200-300 mg q2 wk
Tezepelumab (Tezspire)
TSLP
Works regardless of phenotype (T2-high OR T2-low). NAVIGATOR (2021): reduced exacerbations in eos and non-eos asthma. Pick this if biomarkers don't fit other biologics.
210 mg SC q4 wk
Shortcuts that override the ladder
Scenario
Do This
Why
Pregnancy
Continue all asthma meds. Budesonide is preferred ICS (most safety data). SABA, LABA, montelukast, ICS all considered safe.
Uncontrolled asthma in pregnancy is far more dangerous than the meds (preeclampsia, preterm birth, hypoxia). Don't undertreat.
Aspirin-exacerbated respiratory disease (AERD)
Avoid all NSAIDs + ASA. Add montelukast 10 mg (LTRA helps the leukotriene-driven phenotype). Consider aspirin desensitization in specialty allergy.
AERD triad: asthma + nasal polyps + NSAID sensitivity. Aspirin desensitization improves nasal polyps and asthma control long-term. Dupilumab is very effective in AERD given polyp/eos overlap.
Exercise-induced bronchospasm only
Pre-exercise ICS-formoterol or SABA 15 min before exercise; daily low-dose ICS if frequent
Pre-medication blocks the bronchospasm; chronic ICS dampens airway reactivity. SABA alone is acceptable for occasional symptoms in this single-trigger phenotype.
Vocal cord dysfunction misdiagnosed as asthma
Speech therapy, NOT asthma escalation. Confirm with laryngoscopy showing inspiratory adduction.
VCD doesn't respond to ICS or SABA. Patient comes in "uncontrolled" and gets escalated to triple therapy + biologic without ever fixing the actual problem.
Asthma with eosinophilia > 1500 + multisystem (rash, neuropathy, sinusitis)
EGPA mimics severe asthma but needs systemic immunosuppression (steroids, mepolizumab, rituximab). Missed EGPA causes vasculitic organ damage.
Severe attack at home
Patient-specific written asthma action plan (peak-flow zones, when to increase ICS-formoterol, when to start oral steroid, when to call/ED)
Self-management plans cut hospitalization ~30%. Provide one to every moderate-severe asthmatic at every visit.
Frequent exacerbations on optimized triple
Reassess phenotype, escalate to biologic; if biologic ineligible, consider bronchial thermoplasty in selected centers
Thermoplasty is FDA-approved 2010 for severe asthma; modest effect but option for biologic-failure / ineligible. Don't default to chronic oral steroids when a biologic is feasible.
OCS-dependent asthma (chronic prednisone, even low dose)
Biologic substitution preferred; mepolizumab, benralizumab, dupilumab, and tezepelumab all have OCS-sparing trial data
Long-term OCS causes osteoporosis, DM, cataracts, infection. Biologics let you wean. SIRIUS (mepo), ZONDA (benra), VENTURE (dupi), SOURCE (tezepelumab) all showed OCS reduction.
Stepwise Approach
Key 2023 GINA change: SABA-only rescue is no longer recommended as monotherapy for ANY severity. All patients should have an ICS-containing regimen -either as-needed ICS-formoterol (Track 1) or regular low-dose ICS + SABA rescue (Track 2).
⚠️ SMART/MART is outpatient only. It relies on patient self-titration (extra puffs of the same ICS-formoterol inhaler when symptomatic). For an admitted or ED patient with an acute exacerbation, use nebulized SABA + ipratropium + systemic steroids ± IV magnesium (see Acute Management tab). Start or resume SMART at discharge, not during the acute episode.
✅ Before stepping up therapy, check the 4 T's:Technique (watch them use the inhaler, > 50% use it wrong), Adherence (refill history, are they actually taking it), Triggers (occupational, allergens, smoking, ASA/NSAIDs), Comorbidities (GERD, chronic rhinosinusitis, vocal cord dysfunction, OSA, obesity). Most "uncontrolled" asthma is one of these, not true treatment failure.
MART (GINA term) = SMART therapy (NHLBI / US term) = Single (or Same) Maintenance And Reliever Therapy. One inhaler used for both daily controller and as-needed rescue. Reduces severe exacerbations vs traditional ICS-LABA + SABA PRN. FACET, 1997
Step 4 (Moderate-severe)
Medium-dose ICS-formoterol maintenance + reliever
Medium/high-dose ICS-LABA + SABA PRN
Consider adding LAMA (tiotropium) if uncontrolled. Single-inhaler triple therapy (ICS/LABA/LAMA) reduces exacerbations vs ICS/LABA. CAPTAIN, 2020 · TRIMARAN/TRIGGER, 2019 · SHINE, 2014
Step 5 (Severe)
Refer to specialist. High-dose ICS-LABA + LAMA. Phenotype: eosinophilic → add biologic (anti-IgE, anti-IL5, anti-IL4R). Low-dose OCS as last resort.
Biologics: omalizumab (Xolair) anti-IgE; mepolizumab (Nucala) / benralizumab (Fasenra) anti-IL-5; dupilumab (Dupixent) anti-IL-4Rα; tezepelumab (Tezspire) anti-TSLP. See Medications tab for trial citations and indication criteria.
Asthma vs COPD -Key Differences
Feature
Asthma
COPD
Exacerbation tempo
Fast. Can go from "talking in sentences" to silent chest / peri-arrest in hours. Less reserve, acute bronchospasm on top of baseline normal lungs.
Slow. Usually builds over days. Patients tolerate higher PaCO₂ at baseline (chronic CO₂ retention).
Time to intubation
Sooner. Asthmatics tire and crash quickly once accessory muscles fail. NIV trial is shorter (1–2 h max), low threshold to intubate if not improving.
Later. NIV (BiPAP) avoids intubation in > 80% of COPD exacerbations strong NIV evidence base. Can support on NIV for many hours to days.
NIV response
Less validated. Used as a bridge, not a definitive therapy. If pH or PaCO₂ trending the wrong way at 1–2 h, intubate.
First-line for acute hypercapnic exacerbation (pH < 7.35, PaCO₂ > 45). Reduces intubation, mortality, and length of stay.
Age of onset
Usually childhood / young adult
Usually > 40, smoker
Reversibility
Reversible (FEV₁ improves ≥ 12% + 200 mL post-bronchodilator)
Irreversible (FEV₁/FVC stays < 0.70)
Inflammation
Eosinophilic (Th2, IgE-mediated)
Neutrophilic (CD8+, macrophages)
ICS role
Cornerstone of therapy
Add-on only if eos ≥ 300
🧪 Workup
Workup
Spirometry -FEV₁/FVC <0.70 + reversibility
Peak flow variability >20%
Methacholine challenge -if normal PFTs + suspected asthma
FeNO >25ppb → eosinophilic inflammation
CBC eosinophils -biologic selection
IgE -omalizumab candidacy
Allergy testing
CXR to exclude other diagnoses
💊 Medications
Medications
Drug
Dose
Route
Notes
Fluticasone/salmeterol
100–500/50 BID
DPI
ICS/LABA, Steps 3–4
Budesonide/formoterol
80–160/4.5
DPI
SMART/MART (controller + reliever)
Tiotropium Respimat
2.5 mcg 2 puffs daily
Inhaler
LAMA add-on, Steps 4–5
Prednisone
40–60 mg × 5 d
PO
Exacerbation, no taper needed
Biologic Selection (Step 5 / Severe Asthma)
Pick by phenotype. Eos high or atopic → IL-5 / IL-4R / IgE class. Phenotype unclear or eos low → tezepelumab. All are SQ injections at outpatient pulm or allergy clinic.
Biologic
Target
Use when
Dose
Key trials
Omalizumab (Xolair)
Anti-IgE
Moderate-severe allergic asthma, age ≥ 6, IgE 30–700 IU/mL + perennial aeroallergen sensitivity (skin test or specific IgE +)
75–375 mg SQ q2–4wk (weight + IgE based)
INNOVATE 2005 EXTRA 2011
Mepolizumab (Nucala)
Anti-IL-5
Severe eosinophilic asthma, age ≥ 6, eos ≥ 150 at start OR ≥ 300 in past 12 mo, ≥ 2 exacerbations/yr on high-dose ICS-LABA
100 mg SQ q4wk (adult); 40 mg (peds 6–11)
DREAM 2012 MENSA 2014 SIRIUS 2014
Benralizumab (Fasenra)
Anti-IL-5Rα (ADCC, depletes eos)
Severe eosinophilic asthma, age ≥ 12, eos ≥ 300 (some sources ≥ 150), uncontrolled on high-dose ICS-LABA
30 mg SQ q4wk × 3 doses, then q8wk
SIROCCO 2016 CALIMA 2016 ZONDA 2017
Dupilumab (Dupixent)
Anti-IL-4Rα (blocks IL-4 + IL-13)
Moderate-severe asthma, age ≥ 6, eos ≥ 150 OR FeNO ≥ 25, especially with atopic dermatitis / CRSwNP / EoE. Also OCS-dependent asthma regardless of phenotype
200–300 mg SQ q2wk (after 400–600 mg load)
QUEST 2018 VENTURE 2018
Tezepelumab (Tezspire)
Anti-TSLP (upstream alarmin)
Severe asthma, age ≥ 12, uncontrolled on high-dose ICS-LABA, regardless of eos or IgE. The choice when phenotype is unclear or biomarkers are low
Eos ≥ 300 alone → mepolizumab or benralizumab (q8wk wins on adherence)
Eos ≥ 150 + atopic comorbidity (AD, CRSwNP, EoE) → dupilumab (treats all simultaneously)
OCS-dependent regardless of biomarkers → dupilumab (VENTURE) or benralizumab (ZONDA)
Eos low / phenotype unclear / non-Type 2 → tezepelumab (only biologic with proven non-Type 2 efficacy)
📋 On Rounds
Why can't you give a LABA alone in asthma?
SMART Trial, 2006 (Salmeterol Multicenter Asthma Research Trial) was stopped early because salmeterol monotherapy increased asthma-related deaths. The mechanism: LABAs provide bronchodilation but do NOT address the underlying eosinophilic inflammation. Patients feel better (less bronchospasm) but the inflammation silently worsens → sudden severe exacerbation → death. LABAs must ALWAYS be paired with ICS in asthma.
What is the biggest danger of intubating an asthmatic?
Dynamic hyperinflation (breath stacking → auto-PEEP → hemodynamic collapse). Severe bronchospasm means air goes in but can't get out fast enough before the next breath. Each breath adds to the trapped volume (auto-PEEP) → intrathoracic pressure rises → venous return drops → cardiac output crashes → PEA arrest. Prevention: low respiratory rate (8–12), prolonged expiratory time (I:E 1:4 to 1:5), permissive hypercapnia (accept high CO₂).
Why did GINA remove SABA-only as first-line rescue?
SYGMA 1 & 2, 2018 showed that PRN budesonide-formoterol (ICS-formoterol used only as rescue) reduced severe exacerbations by 64% compared to SABA-only. SABA treats bronchospasm but not the underlying inflammation -patients using only SABA have worse outcomes even if they feel fine between episodes. The paradigm shift: even the mildest asthma has ongoing airway inflammation that needs anti-inflammatory therapy.
A patient on maximum ICS/LABA still has poorly controlled asthma. What are the next steps before adding a biologic?
Before escalating to Step 5 (biologics), always reassess the basics -"treatable traits": (1) Inhaler technique: 70-80% of patients use inhalers incorrectly -observe return demonstration. Spacer for MDIs. (2) Adherence: check refill records -are they actually using the controller? (3) Triggers: allergens (pets, dust mites, mold), occupational exposures, GERD, sinusitis, NSAID/ASA sensitivity
Clinical Examples
📋 Case 1, Acute Severe Asthma Exacerbation
Patient: 22F, moderate persistent asthma on medium-dose ICS/LABA (non-adherent), presents with acute dyspnea, wheezing, and inability to speak in full sentences after URI exposure.
Key findings: HR 124, RR 32, SpO2 88% on RA. Peak flow 120 L/min (predicted 450). Accessory muscle use, paradoxical breathing. ABG: pH 7.38, pCO2 40 (ominous, should be low in acute asthma).
Management:
Continuous albuterol nebulization + ipratropium 500 mcg neb q20min x 3
Methylprednisolone 40-60 mg IV (or prednisolone 40-50 mg PO if tolerating; oral and IV are equally bioavailable, so IV buys nothing unless she cannot swallow). Give within the first hour, why: steroids take 4-6 h to act, so early dosing is what prevents the admission (NNT ~8)
Magnesium sulfate 2g IV over 20 minutes (for severe exacerbation not responding to initial therapy)
If worsening: BiPAP 12/5 as bridge; prepare for intubation with ketamine (bronchodilator properties)
Teaching point: A normal or rising pCO2 in acute asthma is an ominous sign. Patients with severe bronchospasm should be hyperventilating (low pCO2). A "normal" pCO2 of 40 means the patient is tiring and respiratory failure is imminent. Rowe et al., 2000
📋 Case 2, Step-Up Therapy Evaluation in Clinic
Patient: 35M, moderate persistent asthma on fluticasone/salmeterol 250/50 BID. Reports nocturnal symptoms 4x/week, rescue inhaler use daily, 2 ED visits in past 6 months. ACT score 12 (poorly controlled).
Before escalating: assess inhaler technique (observed return demo, incorrect MDI technique identified, corrected with spacer)
Check adherence: pharmacy records show only 40% refill rate, counsel on importance
Trigger assessment: cat at home, no mattress encasement, exercise in cold air
If still uncontrolled after fixing above: Step 5, add tiotropium (Spiriva Respimat)
If refractory: biologic evaluation, eos 480 + FeNO 58 = Type 2 high → consider dupilumab (Dupixent) or mepolizumab (Nucala)
Teaching point: Before adding expensive biologics, fix the basics: 70-80% of patients use inhalers incorrectly, and non-adherence is the most common reason for "refractory" asthma. Always check technique, adherence, and triggers before escalating GINA steps. SYGMA 1 & 2, 2018
📋 Case 3, Near-Fatal Asthma with Intubation
Patient: 19M, severe persistent asthma, prior ICU admission x 2, presents in extremis. Unable to speak, minimal air movement ("silent chest"), altered consciousness.
Ventilator settings: low RR (10-12), long expiratory time (I:E 1:4-1:5), low tidal volume
Permissive hypercapnia (accept pCO2 60-80 as long as pH > 7.20)
If PEA arrest post-intubation: disconnect from vent, compress chest to release trapped air (auto-PEEP)
Continuous albuterol via ETT + methylprednisolone 40-80 mg IV daily (roughly 1 mg/kg; GINA equivalent of prednisolone 40-50 mg PO). Why not more: trials show no added benefit above this range and a real cost in hyperglycemia, myopathy and steroid psychosis, so "125 mg q6h" is not the status asthmaticus dose. Consider an IV epinephrine drip
Teaching point: The "silent chest" with bradypnea is pre-respiratory arrest. After intubation, the greatest danger is dynamic hyperinflation (breath stacking → auto-PEEP → decreased venous return → PEA arrest). If a patient crashes post-intubation, disconnect from the ventilator and manually decompress. Permissive hypercapnia saves lives in status asthmaticus.
📣 Sample Presentation
One-Liner
"Ms. Brown is a 24-year-old with moderate persistent asthma on medium-dose ICS/LABA (Advair 250/50 BID) presenting to clinic with continued nocturnal symptoms 3×/week and rescue inhaler use 4×/week. Poorly controlled."
Key Points to Cover on Rounds
Poorly controlled asthma on Step 4 therapy. Before escalating: (1) Inhaler technique assessed -incorrect MDI technique identified, corrected with spacer education and observed return demo. (2) Adherence: admits missing doses 2-3×/week -counseled. (3) Trigger assessment: cat at home (allergen), no mattress encasement (dust mites), GERD symptoms (omeprazole started). (4) Spirometry today: FEV₁ 72%, 15% improvement post-bronchodilator. If still uncontrolled after optimizing technique/adherence/triggers → Step 5: add tiotropium (Spiriva Respimat) or refer for biologic evaluation (check eosinophils, FeNO, IgE). Asthma Action Plan provided. Plan: return in 6 weeks.
Monitoring
Spirometry at dx, 3-6mo, then q1-2y
ACT ≤19 = not controlled
Exacerbation frequency
FeNO trending
Inhaler technique -observe every visit
Adherence -refill records
⚡ Summary
Summary
The Quiet Chest Is the Emergency
A silent chest means airflow is too low to generate wheeze, and it precedes respiratory arrest.Wheezing that disappears in a deteriorating patient is not improvement. Add a rising CO₂, exhaustion, drowsiness and an inability to speak, and this is an intubation decision, not a nebulizer decision.
Acute Treatment Is Steroids Plus Bronchodilators, Early
Give systemic corticosteroids within the first hour: they take hours to work, so delay simply extends the attack. Continuous or frequent albuterol with ipratropium for severe exacerbations, and magnesium sulfate 2 g IV in severe or refractory cases. Oral steroids are as effective as IV in a patient who can swallow.
Do Not Run the AECOPD Protocol
Asthma and COPD exacerbations are managed differently.Steroid dose and duration, antibiotic use and oxygen targets all differ: antibiotics are not routine in asthma, and there is no permissive hypoxemia target. Mixing the protocols under-treats the asthmatic and over-treats the COPD patient.
Intubation Is High Risk in Status Asthmaticus
Expect hypotension immediately after intubation from breath stacking and dynamic hyperinflation.Ventilate with a low rate, a long expiratory time and permissive hypercapnia, tolerating a high CO₂. If the patient becomes hypotensive, disconnect from the ventilator and press on the chest to allow full exhalation, and exclude pneumothorax. Ketamine is a good induction agent for its bronchodilator effect.
Chronic Therapy Is ICS-Based, Never SABA Alone
GINA no longer recommends short-acting bronchodilator monotherapy at any step.Track 1 uses ICS-formoterol as both reliever and controller, which reduces severe exacerbations compared with SABA reliever. SABA-only treatment is associated with increased asthma death, and high reliever use is itself a red flag.
Check the 4 T's Before Escalating
Technique, adherence (Taking it), Triggers and alternative diagnoses (the Truth of the diagnosis).Most apparently uncontrolled asthma is inhaler technique, adherence, ongoing exposure or a wrong diagnosis, not a need for a higher step. Escalating without checking these treats a problem the drug cannot fix.
Reassess at 4 to 6 Weeks and Step Down Too
Adjust in both directions.Step down after 3 months of good control, reducing the ICS dose gradually rather than stopping it, since asthma is under-treated and over-treated in roughly equal measure. Reassess control formally rather than by asking whether the patient feels alright.
Phenotype Before Reaching for a Biologic
At step 5, check eosinophils, IgE and FeNO.Anti-IgE for allergic asthma, anti-IL-5 for eosinophilic, anti-IL-4R for type 2 disease.Prescribing a biologic without the phenotype wastes an expensive therapy on a patient who will not respond. Also treat the comorbidities that mimic poor control: reflux, obesity, rhinosinusitis, vocal cord dysfunction and anxiety.
RoundsRx Infographic Series · #39 · Respiratory · PDF 152 KB
Text version
Pulmonology · One Pager
Asthma
Step therapy: low-dose ICS → ICS/LABA → add LAMA → biologic. Before escalating: check technique, adherence, triggers. Acute: albuterol + steroids. Action plan for all patients.
🧪 Diagnosis
Variable airflow obstruction + symptoms (wheeze, dyspnea, cough, chest tightness). Spirometry: FEV₁/FVC < 0.70 with significant reversibility (≥ 12% AND ≥ 200 mL). Normal DLCO distinguishes from emphysema.
🚨 Acute Exacerbation
Albuterol neb q20 min × 3 + ipratropium. Systemic steroids: prednisone 40-60 mg × 5 days. MgSO₄ 2g IV if severe. Peak flow or FEV₁ to assess response. If not improving → ICU.
💊 Stepwise Chronic Management
Step 1: PRN low-dose ICS-formoterol. Step 2: daily low-dose ICS. Step 3: medium ICS/LABA. Step 4: high ICS/LABA ± LAMA. Step 5: add biologic (based on eos, FeNO, IgE). Before escalating: fix technique + adherence + triggers.
💊 Key Drugs
Albuterol2 puffs q4-6h PRN
Fluticasone/salmeterol250/50 BID
Prednisone40-60 mg × 5d (exacerbation)
Dupilumab200-300 mg SQ q2wk (biologic)
⚠️ Pitfalls
Incorrect inhaler technique (70-80% use incorrectly -observe return demo)
SABA-only treatment (all persistent asthma needs a controller)
Key trials behind every recommendation in Rounds. Click any trial for a summary and a direct link to PubMed.
⌕
Sepsis & Critical Care
Rivers EGDT Trial
2001 · NEJM · Sepsis
Does early goal-directed therapy improve survival in septic shock?
N=263 with severe sepsis or septic shock in the ED. Protocol-based EGDT (CVP, MAP, ScvO₂ targets + fluids, vasopressors, dobutamine, transfusion) reduced in-hospital mortality from 46.5% to 30.5% (NNT=6). Conclusion: Revolutionized sepsis care. Later trials (ProCESS/ARISE/ProMISe) showed the specific protocol wasn't needed, but early aggressive resuscitation was the key takeaway.
Landmark Positive -changed sepsis management
Surviving Sepsis Campaign Guidelines
2018 · Crit Care Med / Intensive Care Med · Sepsis
What are evidence-based recommendations for sepsis and septic shock management?
Bundle-based approach: 1-hour bundle with antibiotics within 1 hour, 30 mL/kg crystalloid for hypoperfusion, norepinephrine first-line vasopressor, re-measure lactate at 2 hours, source control. Conclusion: Established the 1-hour sepsis bundle as standard of care. Early antibiotics and aggressive resuscitation are the cornerstones.
Guideline
SOAP II Trial
2010 · NEJM · Sepsis / Vasopressors
Is norepinephrine superior to dopamine as first-line vasopressor in shock?
N=1,679 with shock (septic, cardiogenic, hypovolemic). No difference in 28-day mortality, but dopamine caused significantly more arrhythmias (24.1% vs 12.4%). Conclusion: Norepinephrine is the first-line vasopressor for septic shock. Dopamine should be avoided due to arrhythmia risk.
Norepinephrine preferred
SMART Trial
2018 · NEJM · Sepsis / Fluids
Are balanced crystalloids superior to normal saline in critically ill adults?
N=15,802 critically ill adults in medical ICU. Balanced crystalloids (LR or PlasmaLyte) reduced major adverse kidney events at 30 days vs normal saline (14.3% vs 15.4%) with a trend toward mortality benefit. Conclusion: LR or PlasmaLyte is preferred over NS as the default resuscitation fluid. NS causes hyperchloremic acidosis and AKI.
Balanced crystalloids preferred in ICU
APROCCHSS Trial
2018 · NEJM · Sepsis
Do hydrocortisone + fludrocortisone reduce 90-day mortality in septic shock?
N=1,241 with septic shock. Hydrocortisone 200 mg/day plus fludrocortisone 50 mcg/day reduced 90-day mortality (43% vs 49%) and increased vasopressor-free days. Conclusion: Adding fludrocortisone is the key difference from ADRENAL. Surviving Sepsis Campaign recommends steroids in refractory shock.
Positive
PRORATA Trial
2010 · Lancet · Sepsis / Antibiotics
Does procalcitonin-guided antibiotic discontinuation reduce use without harm?
N=621 ICU patients with suspected bacterial infection. PCT-guided antibiotic duration reduced antibiotic days (14.3 vs 17.1) with no increase in mortality or length of stay. Conclusion: Procalcitonin-guided protocols allow earlier antibiotic discontinuation and support antimicrobial stewardship in the ICU.
Positive -supports PCT-guided de-escalation
NICE-SUGAR Trial
2009 · NEJM · Critical Care
Does intensive glucose control improve ICU outcomes?
N=6,104 ICU patients expected to stay ≥3 days. Intensive glucose control (81–108 mg/dL) increased 90-day mortality vs conventional control (≤180 mg/dL), 27.5% vs 24.9%. Severe hypoglycemia was 13x higher (6.8% vs 0.5%). Conclusion: Ended the era of tight glucose control in the ICU. Target 140–180 mg/dL is now standard.
Negative -tight control harms ICU patients
ProCESS Trial
2014 · NEJM · Sepsis
Is protocolized EGDT superior to usual care?
N=1,341 with septic shock across 31 US EDs. Protocol-based EGDT vs protocol-based standard therapy vs usual care showed no difference in 60-day mortality across all 3 groups (~19%). Conclusion: Along with ARISE and ProMISe, showed the specific EGDT protocol (CVP, ScvO₂, dobutamine, transfusion targets) was unnecessary. Early recognition + antibiotics + fluids is what matters.
Neutral -protocol not needed
ADRENAL Trial
2018 · NEJM · Sepsis
Does hydrocortisone reduce 90-day mortality in septic shock?
N=3,658 with septic shock on vasopressors and mechanical ventilation. Hydrocortisone 200 mg/day infusion showed no difference in 90-day mortality but achieved faster shock reversal and shorter ICU stay. Conclusion: Paired with APROCCHSS (2018). Both support steroids for refractory septic shock per Surviving Sepsis guidelines, benefit is hemodynamic, not mortality.
Neutral (faster reversal, no survival benefit)
CORTICUS Trial
2008 · NEJM · Sepsis
Does hydrocortisone improve survival in septic shock?
N=499 with septic shock (less severe than Annane 2002). Hydrocortisone 50 mg q6h for 5 days then taper showed no mortality benefit. Faster shock reversal but more hyperglycemia and superinfections. Conclusion: Steroids hasten vasopressor weaning but don't clearly save lives. Consider only for refractory shock despite adequate fluids and vasopressors.
Neutral -faster shock reversal, no survival benefit
VASST Trial
2008 · NEJM · Sepsis / Vasopressors
Does adding vasopressin to norepinephrine reduce mortality in septic shock?
N=778 with septic shock on norepinephrine. Adding vasopressin (0.01–0.03 units/min) showed no difference in 28-day mortality overall. Trend toward benefit in less severe shock (NE <15 mcg/min). May reduce atrial fibrillation incidence. Conclusion: Vasopressin is a catecholamine-sparing second vasopressor, not a mortality reducer. Used at 0.03 units/min to spare norepinephrine dose.
Neutral -vasopressin as catecholamine-sparing agent
CITRIS-ALI Trial
2019 · JAMA · Sepsis
Does IV vitamin C reduce organ failure in sepsis-induced ARDS?
N=167 with sepsis-induced ARDS. IV vitamin C 200 mg/kg/day for 4 days showed no difference in SOFA score (primary endpoint). A secondary mortality signal was seen (29.8% vs 46.3%) but was not the primary outcome. Conclusion: IV vitamin C is not standard of care for sepsis. The VITAMINS trial (2020) also showed no benefit.
Neutral primary / signal secondary
ALBIOS Trial
2014 · NEJM · Sepsis
Does albumin supplementation (target ≥3.0 g/dL) reduce 28-day mortality in sepsis?
N=1,818 with severe sepsis or septic shock. 20% albumin plus crystalloid vs crystalloid alone showed no reduction in 28-day or 90-day mortality and no benefit on organ failure scores. Conclusion: Albumin is not recommended for routine volume resuscitation in sepsis.
Negative
PROWESS-SHOCK Trial
2012 · NEJM · Sepsis
Does drotrecogin alfa (activated protein C) reduce mortality in septic shock?
N=1,696 with septic shock. Drotrecogin alfa (Xigris) showed no difference in 28-day mortality vs placebo (26.4% vs 24.2%). Drug was withdrawn from the market worldwide. Conclusion: Activated protein C has no role in sepsis management. The drug was pulled in 2011 after failing to replicate the original PROWESS results.
Negative -drug withdrawn
Sepsis-3
2016 · JAMA · Sepsis
Redefined sepsis using SOFA criteria. Replaced SIRS-based definition.
Sepsis redefined as life-threatening organ dysfunction from dysregulated host response (SOFA ≥2). Septic shock = sepsis + vasopressors + lactate >2. Eliminated "severe sepsis" as a category. qSOFA introduced for bedside screening (≥2 of: SBP ≤100, RR ≥22, altered mentation). Conclusion: Shifted focus from inflammation (SIRS) to organ dysfunction as the defining feature of sepsis.
Guideline
Surviving Sepsis Campaign 2021
2021 · Critical Care Medicine · Sepsis
Updated sepsis guidelines with key changes to resuscitation strategy?
Key changes: balanced crystalloids preferred over NS, start vasopressors early if MAP <65 during resuscitation (don't wait for fluids to finish), target MAP 65, albumin not recommended for initial resuscitation, corticosteroids for refractory shock. Conclusion: Major shift toward dynamic assessment over protocolized care. Emphasis on early vasopressor initiation.
Guideline
ANDROMEDA-SHOCK
2019 · JAMA · Sepsis
Peripheral perfusion vs lactate-guided resuscitation in septic shock?
N=424 with septic shock. CRT-guided resuscitation (capillary refill <3s target) showed a trend toward lower 28-day mortality vs lactate-guided (34.9% vs 43.4%), though not statistically significant. Conclusion: Capillary refill time is a valid bedside resuscitation target alongside lactate. Led to the larger ANDROMEDA-SHOCK-2 trial.
Neutral
CENSER Trial
2019 · Annals of EM · Sepsis
Does early norepinephrine improve outcomes in septic shock?
N=310 ED patients with septic shock. Early norepinephrine (within 1 hour) plus fluids achieved shock control in 76% vs 48% with fluids alone. Conclusion: Don't wait to finish fluid resuscitation before starting vasopressors. Early norepinephrine is safe and effective.
Positive
ATHOS-3
2017 · NEJM · Critical Care / Sepsis
Does angiotensin II improve blood pressure in vasodilatory shock on high-dose vasopressors?
N=344 with vasodilatory shock on high-dose vasopressors. Angiotensin II achieved MAP response in 70% vs 23% with placebo. Conclusion: Angiotensin II is a rescue vasopressor option for refractory distributive shock unresponsive to norepinephrine and vasopressin.
Positive
SAFE Study
2004 · NEJM · Critical Care
Is albumin superior to normal saline for ICU fluid resuscitation?
N=6,997 ICU patients. 4% albumin vs normal saline for fluid resuscitation showed no difference in 28-day mortality overall. Albumin was harmful in the traumatic brain injury subgroup. Conclusion: Albumin is not superior to crystalloids for most ICU patients. Avoid in TBI.
Neutral
VISEP
2008 · NEJM · Critical Care
What are the effects of intensive insulin and HES in severe sepsis?
N=600 with severe sepsis. HES increased AKI and need for RRT vs Ringer's lactate. Intensive insulin increased hypoglycemia without benefit. Conclusion: HES is harmful in sepsis, causes renal failure. Avoid all starches in the critically ill.
Negative
6S Trial
2012 · NEJM · Critical Care
Is HES inferior to Ringer's acetate for fluid resuscitation in severe sepsis?
N=798 with severe sepsis. HES 130/0.42 increased 90-day mortality (51% vs 43%) and need for renal replacement therapy vs Ringer's acetate. Conclusion: Along with VISEP and CHEST, this trial ended HES use in the critically ill. Crystalloids are the standard.
Negative
SUP-ICU Trial
2018 · NEJM · Critical Care
Does routine stress ulcer prophylaxis benefit ICU patients?
N=3,298 ICU patients at risk for GI bleeding. Pantoprazole 40 mg daily vs placebo showed no difference in 90-day mortality or clinically important GI bleeding. Conclusion: Not all ICU patients need stress ulcer prophylaxis. Reserve for high-risk patients (ventilated >48h, coagulopathy, prior GI bleed).
Neutral
ARDS & Ventilation
ARDSnet ARMA Trial
2000 · NEJM · ARDS / Ventilation
Does low tidal volume ventilation (6 mL/kg PBW) reduce mortality in ARDS?
N=861 with ARDS on mechanical ventilation. Low tidal volume (6 mL/kg PBW, Pplat ≤30 cmH₂O) reduced 28-day mortality from 39.8% to 31% vs 12 mL/kg, with more ventilator-free days. Conclusion: Foundation of lung-protective ventilation. All ARDS patients should receive 6 mL/kg PBW tidal volumes with plateau pressure ≤30.
Positive -practice changing
PROSEVA Trial
2013 · NEJM · ARDS
Does prone positioning reduce 28-day mortality in severe ARDS?
N=466 with severe ARDS (P/F <150) on lung-protective ventilation. Prone positioning ≥16 hours/day cut 28-day mortality in half (16% vs 32.8%) with no increase in complications. Conclusion: Proning ≥16h/day is standard of care for severe ARDS. Must be established on lung-protective ventilation first.
Positive -practice changing
FACTT Trial
2006 · NEJM · ARDS
Does conservative vs liberal fluid strategy improve outcomes in ARDS?
N=1,000 with ARDS. Conservative fluid management produced more ventilator-free days (14.6 vs 12.1) and less need for RRT, though no mortality difference. Conclusion: Supports the "dry lung" strategy in ARDS. Target neutral to negative fluid balance after initial resuscitation is complete.
Conservative strategy preferred
ACURASYS Trial
2010 · NEJM · ARDS
Does early cisatracurium infusion improve outcomes in moderate-severe ARDS?
N=340 with moderate-severe ARDS (P/F <150). 48-hour cisatracurium infusion reduced 90-day mortality (31.6% vs 40.7%), improved oxygenation at 48h, and reduced barotrauma. Conclusion: Supported early NMB in severe ARDS, but later superseded by ROSE (2019) which showed no benefit when lighter background sedation is used.
Positive
EOLIA Trial
2018 · NEJM · ARDS
Does early VV-ECMO reduce 60-day mortality in very severe ARDS?
N=249 with very severe ARDS (P/F <80). 60-day mortality was 35% vs 46% but did not reach significance. 35% of the control arm crossed over to ECMO. Bayesian re-analysis showed 88% probability of benefit. Conclusion: ECMO should be considered for refractory severe ARDS at ECMO-capable centers despite the negative primary endpoint. High crossover rate diluted the treatment effect.
Negative (trend to benefit)
ROSE Trial
2019 · NEJM · ARDS
Does early cisatracurium improve outcomes in ARDS when lighter sedation is standard?
N=1,006 with moderate-severe ARDS. Early continuous cisatracurium showed no difference in 90-day mortality vs usual care with lighter sedation (42.5% vs 42.8%), with more cardiovascular adverse events. Conclusion: Supersedes ACURASYS when deep sedation is not used. NMB may still be considered for ventilator dyssynchrony or refractory hypoxemia.
Negative -NMB not routinely recommended
OSCILLATE Trial
2013 · NEJM · ARDS
Does HFOV improve outcomes in moderate-severe ARDS?
N=548 with moderate-severe ARDS. Trial stopped early, in-hospital mortality was higher with HFOV (47% vs 35%). Conclusion: HFOV is not recommended for ARDS. Paired with OSCAR trial (also no benefit). Conventional lung-protective ventilation remains the gold standard.
Negative -HFOV harmful
DEXA-ARDS
2020 · Lancet Resp Med · ARDS
Does dexamethasone improve outcomes in moderate-severe ARDS?
N=277 with moderate-severe ARDS (P/F ≤200). Dexamethasone 20 mg ×5 days then 10 mg ×5 days increased ventilator-free days (4.8 vs 2.6) and reduced 60-day mortality (21% vs 36%). Conclusion: Supports early dexamethasone in established moderate-severe ARDS.
Positive
LUNG SAFE
2016 · JAMA · ARDS
How well is ARDS recognized and managed worldwide?
N=29,144 ICU patients across 50 countries. 10% of ICU admissions had ARDS, but 40% were not recognized by clinicians. Lung-protective ventilation was used in only 35% of cases. Conclusion: ARDS is massively underdiagnosed and undertreated worldwide. Always consider it in hypoxemic patients.
Does pairing spontaneous awakening trials with spontaneous breathing trials improve outcomes?
N=336 mechanically ventilated ICU patients. Daily SAT paired with SBT increased ventilator-free days (14.7 vs 11.6), shortened ICU stay, and reduced 1-year mortality by 32%. Conclusion: Established daily SAT + SBT pairing as standard of care. Foundation of the ABCDEF bundle.
Positive -ABCDEF bundle foundation
MENDS Trial
2007 · JAMA · Sedation
Does dexmedetomidine reduce delirium vs lorazepam in mechanically ventilated patients?
N=106 mechanically ventilated ICU patients requiring sedation. Dexmedetomidine produced more delirium/coma-free days than lorazepam with no mortality difference. Conclusion: Paired with SEDCOM, both support dexmedetomidine over benzodiazepines for ICU sedation to reduce delirium.
Dexmedetomidine preferred
SEDCOM Trial
2009 · JAMA · Sedation
Does dexmedetomidine reduce delirium vs midazolam in mechanically ventilated patients?
N=375 mechanically ventilated ICU patients needing sedation >24h. Dexmedetomidine reduced delirium prevalence (54% vs 76.6%) and shortened time to extubation vs midazolam. Conclusion: With MENDS, established dexmedetomidine as the preferred sedative to reduce delirium in ventilated ICU patients.
Dexmedetomidine preferred
MIND-USA Trial
2018 · NEJM · Sedation / Delirium
Do haloperidol or ziprasidone reduce delirium duration in critically ill patients?
N=566 critically ill adults with delirium. IV haloperidol, IV ziprasidone, and placebo showed no difference in delirium/coma-free days, 90-day mortality, or ventilator-free days. Conclusion: Antipsychotics should not be routinely used for ICU delirium. Focus on the ABCDEF bundle and non-pharmacologic measures instead.
Negative -antipsychotics don't treat ICU delirium
PADIS Guidelines
2018 · Critical Care Medicine · Critical Care
What are best practices for pain, agitation, delirium, immobility, and sleep in ICU?
Analgesia-first approach, target light sedation (RASS 0 to –2), daily SAT + SBT, avoid benzodiazepines, early mobility, and sleep hygiene. Conclusion: Foundation of modern ICU sedation practice. The ABCDEF bundle integrates all these recommendations into a daily workflow.
Guideline
ACS, Acute Management
ISIS-2 Trial
1988 · Lancet · ACS / MI
Does aspirin and/or streptokinase reduce mortality in acute MI?
N=17,187 with suspected acute MI. Aspirin alone reduced 5-week vascular mortality by 23%, streptokinase alone by 25%, and the combination by 42%. Conclusion: Established aspirin as life-saving in acute MI. One of the most influential trials in cardiology history.
Landmark Positive
PLATO Trial
2009 · NEJM · Cardiology / ACS
Is ticagrelor superior to clopidogrel in ACS?
N=18,624 hospitalized with ACS (STEMI or NSTEMI). Ticagrelor 90 mg BID reduced CV death, MI, and stroke vs clopidogrel 75 mg daily with no increase in major bleeding. All-cause mortality also reduced. Conclusion: Ticagrelor is the preferred P2Y12 inhibitor in ACS. Reversible binding with faster onset/offset than clopidogrel, and avoids CYP2C19 resistance issues.
Positive, ticagrelor preferred P2Y12
TRITON-TIMI 38 Trial
2007 · NEJM · Cardiology / ACS
Is prasugrel superior to clopidogrel in ACS patients undergoing PCI?
N=13,608 ACS patients scheduled for PCI. Prasugrel reduced CV death, MI, stroke, and stent thrombosis vs clopidogrel, but increased major and fatal bleeding. Conclusion: More potent but riskier. Contraindicated in prior stroke/TIA (net harm), age ≥75 (no net benefit), and weight <60 kg. Use ticagrelor instead in these patients.
Positive with caution, more bleeding
ESSENCE Trial
1997 · NEJM · Cardiology / ACS
Is enoxaparin (LMWH) superior to unfractionated heparin in unstable angina / NSTEMI?
N=3,171 with unstable angina or non-Q-wave MI. Enoxaparin 1 mg/kg SC BID reduced death, MI, and recurrent angina at 14 and 30 days vs UFH IV drip, with no increase in major bleeding. Conclusion: Established LMWH as preferred over UFH in NSTEMI. Enoxaparin offers predictable dosing without aPTT monitoring. UFH still preferred if PCI planned within 24h (easier to reverse).
Positive, enoxaparin superior to UFH in UA/NSTEMI
TIMACS Trial
2009 · NEJM · Cardiology / ACS
Does early (<24h) vs delayed (>36h) intervention improve outcomes in NSTEMI?
N=3,031 with NSTEMI. No overall difference, but in high-risk patients (GRACE >140), early intervention within 24h significantly reduced death/MI/stroke (13.9% vs 21.0%). Low-risk patients could safely wait. Conclusion: GRACE >140 should trigger an early invasive strategy within 24h. Low-risk patients can safely undergo delayed catheterization.
Positive in high-risk (GRACE >140)
HEART Pathway Trial
2015 · Circulation · Cardiology / ACS
Can HEART score safely identify low-risk chest pain for early ED discharge?
N=282 ED patients with acute chest pain. HEART score 0–3 plus negative serial troponins safely reduced cardiac testing by 12% and shortened hospital stay. 30-day MACE in the low-risk group was <2%. Conclusion: HEART 0–3 with negative troponins = safe for discharge with outpatient follow-up. Now widely adopted in EDs for chest pain risk stratification.
Positive, safe early discharge
STREAM
2013 · NEJM · Cardiology
Is a pharmaco-invasive strategy noninferior to primary PCI for early STEMI?
N=1,892 STEMI patients presenting within 3h who could not get primary PCI within 1h. Tenecteplase followed by transfer for angiography within 6–24h was noninferior to primary PCI. Conclusion: When PCI is delayed >120 min, lyse first then transfer. Pharmaco-invasive strategy is valid for STEMI at non-PCI centers.
Neutral
Stable CAD & Revascularization
COURAGE Trial
2007 · NEJM · Stable CAD
Does PCI beat optimal medical therapy in stable CAD?
N=2,287 with stable CAD and objective ischemia. PCI plus optimal medical therapy showed no difference in death or MI vs medical therapy alone at 4.6 years. PCI provided better early angina relief only. Conclusion: Medical therapy is first-line for stable angina. PCI is reserved for refractory symptoms, not for outcome benefit.
Neutral, PCI did not beat medical therapy
FREEDOM Trial
2012 · NEJM · Revascularization
CABG vs PCI in diabetic patients with multivessel CAD?
N=1,900 diabetic patients with multivessel CAD. CABG significantly reduced death and MI at 5 years vs PCI with drug-eluting stents (18.7% vs 26.6%), though stroke was higher with CABG (5.2% vs 2.4%). Conclusion: Diabetic patients with multivessel disease should be referred for CABG unless high surgical risk.
Positive, CABG wins in diabetics
SYNTAX Trial
2009 · NEJM / Lancet · Revascularization
PCI vs CABG for complex multivessel or left-main CAD?
N=1,800 with three-vessel or left-main CAD. CABG was superior for complex disease (high SYNTAX score ≥33). PCI was comparable for low-complexity lesions. Conclusion: Introduced the SYNTAX score for Heart Team decision-making. High complexity = CABG, low complexity = PCI acceptable.
Does simvastatin reduce mortality in patients with CHD?
N=4,444 with CHD and elevated cholesterol. Simvastatin over 5.4 years reduced all-cause mortality by 30%, coronary death by 42%, and major coronary events by 34%. Conclusion: First trial to prove statins reduce mortality. Changed lipid management forever and launched the statin era.
Landmark Positive, statins save lives
PROVE IT–TIMI 22 Trial
2004 · NEJM · ACS / Lipids
Is intensive statin therapy better than standard therapy after ACS?
N=4,162 hospitalized for ACS. Atorvastatin 80 mg (intensive) reduced death, MI, unstable angina, revascularization, and stroke by 16% vs pravastatin 40 mg (standard). Conclusion: Established that "lower is better" for LDL after ACS. Foundation for high-intensity statin guidelines in all ACS patients.
Positive, high-intensity statin after ACS
SAVE Trial
1992 · NEJM · Cardiology
Does captopril improve outcomes post-MI with LV dysfunction?
N=2,231 post-MI patients with EF ≤40%. Captopril reduced mortality by 19% and heart failure by 37% vs placebo. Conclusion: Established ACE inhibitors post-MI for LV dysfunction. Start ACEi in all post-MI patients with reduced EF.
Positive, ACEi post-MI
LoDoCo2 Trial
2020 · NEJM · Cardiology / Secondary Prevention
Does low-dose colchicine reduce CV events in chronic coronary disease?
N=5,522 with chronic coronary disease (> 6 months stable), on aspirin + statin. Colchicine 0.5 mg daily reduced the composite of CV death, MI, ischemic stroke, or ischemia-driven revascularization by 31% (6.8% vs 9.6%, HR 0.69) over 28.6 months. NNT ~36. Conclusion: Pivotal trial for colchicine in chronic ASCVD. Led to FDA approval of Lodoco (June 2023), the first anti-inflammatory drug approved for CV risk reduction. Layered on top of aspirin + statin.
Landmark Positive, secondary prevention
COLCOT Trial
2019 · NEJM · Cardiology / Post-MI
Does colchicine started within 30 days of MI reduce recurrent CV events?
N=4,745 with MI in the prior 30 days. Colchicine 0.5 mg daily reduced the primary composite (CV death, cardiac arrest, MI, stroke, urgent revascularization) by 23% (5.5% vs 7.1%, HR 0.77) at 22.6 months. Stroke reduced by 74%. Slightly more pneumonia with colchicine. Conclusion: First major trial showing colchicine benefit post-MI. With LoDoCo2, formed the evidence base for FDA approval of low-dose colchicine for CV secondary prevention.
Positive, 23% RRR in post-MI MACE
CLEAR SYNERGY (OASIS-9)
2024 · NEJM · Cardiology / Post-MI
Does colchicine (and spironolactone) reduce CV events started at the time of PCI for MI?
N=7,062 with recent STEMI or NSTEMI undergoing PCI. Factorial design (colchicine vs placebo, spironolactone vs placebo). Over 3 years, colchicine did NOT reduce the composite of CV death, MI, stroke, or ischemia-driven revascularization (9.1% vs 9.3%, HR 0.99). More diarrhea with colchicine. Conclusion: The largest colchicine-in-ACS trial was neutral. Suggests benefit is restricted to the chronic stable phase (as in LoDoCo2), not the immediate post-ACS window. Favor starting colchicine in chronic follow-up rather than acutely.
Neutral, tempers acute-phase enthusiasm
Heart Failure
SOLVD Treatment Trial
1991 · NEJM · Heart Failure
Does enalapril reduce mortality in HFrEF?
N=2,569 with EF ≤35% and NYHA II–IV symptoms. Enalapril reduced all-cause mortality by 16% and HF hospitalization by 26%. Conclusion: Established ACE inhibitors as foundational therapy in HFrEF. One of the four pillars of GDMT.
Landmark Positive -ACEi standard for HFrEF
PARADIGM-HF Trial
2014 · NEJM · Heart Failure
Is sacubitril/valsartan superior to enalapril in HFrEF?
N=8,442 NYHA II–IV, EF ≤40% on standard GDMT. Sacubitril/valsartan (Entresto) reduced CV death or HF hospitalization by 20% and all-cause mortality by 16% vs enalapril. Stopped early. Conclusion: ARNI replaced ACEi/ARB as pillar #1 of HFrEF GDMT. Requires 36h ACEi washout before starting.
Landmark Positive -ARNI replaced ACEi
RALES Trial
1999 · NEJM · Heart Failure
Does spironolactone reduce mortality in severe HFrEF?
N=1,663 NYHA III–IV, EF ≤35%, already on ACEi + loop diuretic. Spironolactone 25–50 mg reduced all-cause mortality by 30% and HF hospitalization by 35%. Stopped early for benefit. Conclusion: Established MRAs as pillar #3 of HFrEF GDMT. Watch for hyperkalemia (K >5.0) and renal function.
Landmark Positive -MRA became HFrEF pillar
MADIT-II Trial
2002 · NEJM · Heart Failure / Arrhythmia
Does prophylactic ICD reduce mortality post-MI with low EF?
N=1,232 with prior MI and EF ≤30%. Prophylactic ICD reduced all-cause mortality by 31% (14.2% vs 19.8%), driven by reduction in arrhythmic death. Conclusion: Established the ICD indication: prior MI + EF ≤35% (after 40 days post-MI, 90 days post-revascularization).
Positive -ICD for primary prevention
CONSENSUS Trial
1987 · NEJM · Heart Failure
Does enalapril improve survival in severe heart failure?
N=253 NYHA IV heart failure. Enalapril reduced mortality by 40% at 6 months. Conclusion: First trial showing ACE inhibitors save lives in heart failure. Launched the neurohormonal era of HF therapy.
Positive
COPERNICUS
2001 · NEJM · Heart Failure
Does carvedilol improve survival in severe HFrEF?
N=2,289 NYHA IV, EF <25%. Carvedilol reduced mortality by 35%. Conclusion: Proved beta-blockers are safe and effective even in severe/decompensated HF once the patient is euvolemic.
Positive
CIBIS-II
1999 · Lancet · Heart Failure
Does bisoprolol reduce mortality in HFrEF?
N=2,647 NYHA III–IV, EF ≤35%. Bisoprolol reduced all-cause mortality by 34%. Conclusion: Along with MERIT-HF and COPERNICUS, proved the beta-blocker class effect in HFrEF. Only carvedilol, metoprolol succinate, and bisoprolol are evidence-based.
Positive
MERIT-HF
1999 · Lancet · Heart Failure
Does metoprolol succinate improve outcomes in HFrEF?
N=3,991 NYHA II–IV, EF ≤40%. Metoprolol succinate (CR/XL) reduced all-cause mortality by 34%. Stopped early for benefit. Conclusion: Established beta-blockers as standard HFrEF therapy. One of three landmark BB trials (with CIBIS-II and COPERNICUS).
Positive
DAPA-HF
2019 · NEJM · Heart Failure
Does dapagliflozin improve outcomes in HFrEF regardless of diabetes status?
N=4,744 with EF ≤40% (with or without diabetes). Dapagliflozin reduced CV death and HF hospitalization by 26%. Conclusion: First SGLT2i trial in HF regardless of diabetes status. Made SGLT2 inhibitors the 4th pillar of HFrEF GDMT.
Positive
EMPEROR-Reduced
2020 · NEJM · Heart Failure
Does empagliflozin improve outcomes in HFrEF?
N=3,730 with EF ≤40%. Empagliflozin reduced CV death and HF hospitalization by 25%. Conclusion: Confirmed the SGLT2i class effect in HFrEF alongside DAPA-HF. Both dapagliflozin and empagliflozin are guideline-recommended.
Positive
DIGIT-HF
2025 · NEJM · Heart Failure
Does digitoxin added to GDMT improve outcomes in advanced HFrEF?
Positive
EMPHASIS-HF
2011 · NEJM · Heart Failure
Does eplerenone improve outcomes in mild HFrEF?
N=2,737 NYHA II, EF ≤30%. Eplerenone reduced CV death and HF hospitalization by 37%. Conclusion: Extended the MRA benefit beyond severe HF (RALES) to mild HFrEF. MRAs are a pillar for all symptomatic HFrEF.
Positive
DELIVER
2022 · NEJM · Heart Failure
Does dapagliflozin improve outcomes in HFpEF?
N=6,263 with EF >40%. Dapagliflozin reduced CV death and HF hospitalization by 18%. Conclusion: Confirmed SGLT2i benefit across the entire EF spectrum, works in both HFrEF and HFpEF.
Positive
EMPEROR-Preserved
2021 · NEJM · Heart Failure
Does empagliflozin improve outcomes in HFpEF?
N=5,988 with EF >40%. Empagliflozin reduced HF hospitalization by 29%. Conclusion: First drug to show benefit in HFpEF, a game-changer for a population with historically no effective therapies.
Positive
A-HeFT
2004 · NEJM · Heart Failure
Does hydralazine-nitrate improve outcomes in Black patients with HF?
N=1,050 self-identified Black patients with NYHA III–IV HF. BiDil (hydralazine + isosorbide dinitrate) reduced mortality by 43%. Stopped early for benefit. Conclusion: Add hydralazine-nitrate for self-identified Black patients with HFrEF already on optimal GDMT.
Positive
DIG Trial
1997 · NEJM · Heart Failure
Does digoxin reduce mortality in HFrEF?
N=6,800 with EF ≤45%. Digoxin reduced HF hospitalizations but showed no mortality benefit. Conclusion: Digoxin helps symptoms but doesn't save lives. Reserved for refractory HF or rate control in AF when other agents fail.
Neutral
SHIFT Trial
2010 · Lancet · Heart Failure
Does ivabradine improve outcomes in HFrEF with elevated heart rate?
N=6,558 with EF ≤35%, HR ≥70 in sinus rhythm. Ivabradine reduced CV death and HF hospitalization by 18%. Conclusion: For HFrEF patients in sinus rhythm with HR ≥70 despite maximally tolerated beta-blocker.
Positive
VICTORIA
2020 · NEJM · Heart Failure
Does vericiguat reduce events in worsening HFrEF?
N=5,050 with worsening HFrEF. Vericiguat (soluble guanylate cyclase stimulator) reduced CV death and HF hospitalization by 10%, a modest but significant benefit. Conclusion: Add-on option for patients failing standard GDMT with recent HF hospitalization.
Positive
STRONG-HF
2022 · NEJM · Heart Failure
Does rapid GDMT titration after HF hospitalization improve outcomes?
N=1,078 discharged after acute HF. Rapid up-titration of GDMT within 2 weeks reduced HF readmission and death by 34% vs usual care. Conclusion: Don't wait, optimize GDMT fast after discharge. Aggressive early titration is safe and beneficial.
Positive
EMPULSE
2022 · Nature Medicine · Heart Failure
Does empagliflozin initiated during HF hospitalization improve outcomes?
N=530 hospitalized for acute HF. Empagliflozin started in-hospital improved a composite of death, HF events, and symptoms at 90 days. Conclusion: Start SGLT2i in-hospital during acute HF, don't wait for discharge.
Positive
TOPCAT
2014 · NEJM · Heart Failure
Does spironolactone improve outcomes in HFpEF?
N=3,445 with EF ≥45%. Primary endpoint was negative overall, but the Americas subgroup showed an 18% benefit. Conclusion: Regional differences (Russia/Georgia sites questioned) muddied results. Americas-only analysis suggests MRA may help HFpEF, but evidence is not definitive.
Neutral
CHARM-Preserved
2003 · Lancet · Heart Failure
Does candesartan improve outcomes in HFpEF?
N=3,023 with EF >40%. Candesartan showed a modest trend toward fewer HF hospitalizations but was not statistically significant. Conclusion: ARBs alone don't clearly help HFpEF. SGLT2 inhibitors (EMPEROR-Preserved, DELIVER) are the real game-changers for this population.
Neutral
TRANSFORM-HF
2022 · NEJM · Heart Failure
Is torsemide superior to furosemide in HF?
N=2,859 hospitalized for HF. Torsemide vs furosemide showed no difference in all-cause mortality at 12 months. Conclusion: Torsemide is not superior to furosemide for HF outcomes. Either loop diuretic is acceptable.
Neutral
STEP-HFpEF
2023 · NEJM · Heart Failure / Endocrinology
Does semaglutide improve outcomes in obese HFpEF?
N=529 with HFpEF, BMI ≥30, no diabetes. Semaglutide reduced body weight by 13.3% and improved symptoms, exercise capacity, and 6-minute walk distance. Conclusion: GLP-1 RA for obese HFpEF, treats the obesity driving the heart failure. Led to the larger SUMMIT trial.
Positive
SCD-HeFT
2005 · NEJM · Heart Failure / Cardiology
Does ICD implantation reduce mortality in moderate heart failure?
N=2,521 NYHA II–III, EF ≤35%. ICD reduced all-cause mortality by 23%. Amiodarone was no better than placebo. Conclusion: With MADIT-II, established primary prevention ICD criteria for HFrEF patients with EF ≤35%.
Positive
MADIT-CRT
2009 · NEJM · Heart Failure / Cardiology
Does CRT-D improve outcomes in mild HF?
N=1,820 NYHA I–II, EF ≤30%, QRS ≥130 ms. CRT-D reduced HF events by 34% vs ICD alone. Conclusion: CRT benefit requires LBBB and QRS ≥150 ms. Less benefit with non-LBBB morphology or narrower QRS.
Positive
RAFT
2010 · NEJM · Heart Failure / Cardiology
Does CRT-D reduce mortality vs ICD in moderate HF?
N=1,798 NYHA II–III, EF ≤30%, QRS ≥120 ms. CRT-D reduced all-cause mortality by 25% vs ICD alone. Conclusion: Confirmed mortality benefit of CRT in patients meeting criteria (EF ≤35%, LBBB, QRS ≥150 ms).
Positive
Cardiogenic Shock
SHOCK Trial
1999 · NEJM · Cardiogenic Shock
Does early revascularization reduce mortality in cardiogenic shock complicating MI?
N=302 with cardiogenic shock complicating acute MI. 30-day mortality was similar, but 6-month and 1-year mortality were significantly reduced with early revascularization (PCI or CABG). Conclusion: Established early PCI/catheterization as standard of care for cardiogenic shock complicating MI.
Early revascularization preferred
IABP-SHOCK II Trial
2012 · NEJM · Cardiogenic Shock
Does IABP reduce 30-day mortality in cardiogenic shock complicating MI?
N=600 with cardiogenic shock complicating acute MI undergoing revascularization. IABP showed no difference in 30-day mortality (39.7% vs 41.3%) and no benefit on any secondary endpoint. Conclusion: Led to downgrade of IABP in ESC/ACC guidelines. IABP is no longer routinely recommended in cardiogenic shock.
Negative -practice changing
Cardiology, Anticoagulation & AF
RE-LY
2009 · NEJM · Cardiology / Anticoagulation
Is dabigatran noninferior or superior to warfarin in AF?
N=18,113 with AF. Dabigatran 150 mg BID reduced stroke by 34% vs warfarin. The 110 mg dose had less bleeding. Conclusion: First DOAC approved for AF. Only DOAC with a specific reversal agent (idarucizumab).
Positive
ARISTOTLE
2011 · NEJM · Cardiology / Anticoagulation
Is apixaban superior to warfarin in atrial fibrillation?
N=18,201 with AF. Apixaban reduced stroke by 21%, major bleeding by 31%, and mortality by 11% vs warfarin. Conclusion: Best overall efficacy and safety profile among DOACs for AF. The go-to DOAC for most patients.
Positive
ROCKET AF
2011 · NEJM · Cardiology / Anticoagulation
Is rivaroxaban noninferior to warfarin for stroke prevention in AF?
N=14,264 high-risk AF patients. Rivaroxaban was noninferior to warfarin for stroke prevention with less intracranial bleeding. Conclusion: Once-daily DOAC option for AF. Must be taken with food for adequate absorption.
Positive
ENGAGE AF-TIMI 48
2013 · NEJM · Cardiology / Anticoagulation
Is edoxaban noninferior to warfarin for stroke prevention in AF?
N=21,105 with AF. Edoxaban 60 mg was noninferior to warfarin for stroke prevention with 20% less major bleeding. Conclusion: Fourth DOAC for AF. Once daily dosing. Dose reduce to 30 mg if CrCl 15–50 or weight ≤60 kg.
Positive
EAST-AFNET 4
2020 · NEJM · Cardiology / Arrhythmia
Does early rhythm control improve outcomes in recently diagnosed AF?
N=2,789 with recently diagnosed AF. Early rhythm control reduced CV death, stroke, and HF hospitalization by 21% vs rate control. Conclusion: Changed the paradigm, early rhythm control (within 1 year of AF diagnosis) is better than waiting. Don't default to rate control.
Positive
RACE II
2010 · NEJM · Cardiology
Is lenient rate control noninferior to strict rate control in permanent AF?
N=614 with permanent AF. No difference in CV events between lenient (HR <110) and strict (<80) rate control. Conclusion: Lenient rate control is acceptable in permanent AF. Don't chase HR <80, a target of <110 is sufficient.
Neutral
PARTNER 3
2019 · NEJM · Cardiology
Is TAVR noninferior to surgery in low-risk severe aortic stenosis?
N=1,000 with severe aortic stenosis and low surgical risk. TAVR (SAPIEN 3) reduced death, stroke, and rehospitalization at 1 year (8.5% vs 15.1%) vs surgical valve replacement. Conclusion: TAVR expanded to low-risk patients. No longer just for inoperable or high-risk patients.
Positive
RE-VERSE AD
2017 · NEJM · Hematology / Anticoagulation
Does idarucizumab reverse dabigatran anticoagulation?
N=503 on dabigatran with serious bleeding or needing urgent surgery. Idarucizumab 5 g IV reversed anticoagulation within minutes in 98% of patients. Conclusion: Immediate complete reversal of dabigatran. Only works for dabigatran, not other DOACs.
Positive
ANNEXA-4
2019 · NEJM · Hematology / Anticoagulation
Does andexanet alfa reverse factor Xa inhibitor anticoagulation?
N=352 on apixaban or rivaroxaban with major bleeding. Andexanet alfa reduced anti-Xa activity by 92% and achieved good hemostasis in 82%. Conclusion: Reversal agent for apixaban and rivaroxaban in life-threatening bleeding. Expensive, some centers use 4-factor PCC as an alternative.
Positive
Hypertension
SPRINT Trial
2015 · NEJM · Hypertension
Does intensive BP control (<120) reduce CV events?
N=9,361 adults with high CV risk but without diabetes. Intensive SBP target <120 reduced MACE by 25% and all-cause mortality by 27%. Stopped early. More AKI and hypotension in intensive group. Conclusion: Changed BP targets for high-risk non-diabetic patients. Watch for AKI, syncope, and electrolyte abnormalities.
Positive -lower target saves lives
ALLHAT Trial
2002 · JAMA · Hypertension
Which antihypertensive class is best?
N=33,357 aged ≥55 with HTN. Chlorthalidone (thiazide) vs amlodipine (CCB) vs lisinopril (ACEi) vs doxazosin (alpha-blocker). No difference in fatal CHD/nonfatal MI among the first three. Chlorthalidone SUPERIOR to amlodipine for HF (38% lower). Chlorthalidone SUPERIOR to lisinopril for HF, stroke (especially Black patients, ~40% lower), and combined CVD. Doxazosin arm stopped early (~2x HF). Conclusion: Largest antihypertensive trial ever. Thiazide first-line, alpha-blockers NOT for monotherapy.
Thiazide remains first-line
PATHWAY-2
2015 · Lancet · Cardiology / Hypertension
Is spironolactone the best add-on for resistant hypertension?
N=335 with resistant HTN on 3+ drugs. Spironolactone 25–50 mg was superior to placebo, doxazosin, and bisoprolol, reducing SBP by 8.7 mmHg more than placebo. Conclusion: Spironolactone is the preferred 4th-line agent for resistant hypertension.
Positive
Pulmonology, COPD
Brochard et al. NIV in AECOPD
1995 · NEJM · AECOPD
Does NIV (BiPAP) reduce intubation and mortality in AECOPD with respiratory failure?
N=85 with AECOPD and acute respiratory failure. NIV (BiPAP) reduced intubation from 74% to 26%, reduced in-hospital mortality, and shortened ICU stay. Conclusion: Established NIV as standard of care for AECOPD with hypercapnic respiratory failure (pH <7.35, pCO₂ >45).
Positive -landmark trial
Austin et al. Oxygen Titration Trial
2010 · BMJ · AECOPD
Does titrated O₂ (SpO₂ 88–92%) reduce mortality vs high-flow O₂ in AECOPD?
N=405 with AECOPD treated by paramedics pre-hospital. Titrated O₂ targeting SpO₂ 88–92% reduced mortality by 78% vs high-flow O₂ (8–10 L/min), with less hypercapnia and respiratory acidosis. Conclusion: Drives the 88–92% SpO₂ target in AECOPD. High-flow O₂ worsens hypercapnia via Haldane effect and V/Q mismatch.
Positive -practice changing
Plant et al. NIV on General Wards
2000 · Lancet · AECOPD
Is early NIV feasible and beneficial for AECOPD with mild-moderate acidosis on general wards?
N=236 with AECOPD and mild-moderate acidosis (pH 7.25–7.35). NIV on general wards reduced intubation (15% vs 27%) and in-hospital mortality (10% vs 20%). Conclusion: Supports ward-based NIV for pH 7.25–7.35. ICU-level NIV for pH <7.25 or deterioration on ward NIV.
Positive -NIV effective on wards
Anthonisen Criteria Trial
1987 · Ann Intern Med · AECOPD
Do antibiotics benefit patients with AECOPD?
N=173 with COPD and acute exacerbation. Antibiotics benefited Type 1 (all 3 cardinal symptoms) and Type 2 (2 of 3) exacerbations but not Type 3 (1 symptom). Conclusion: Cardinal symptoms: increased dyspnea, increased sputum volume, increased sputum purulence. Antibiotics indicated when ≥2 are present.
Positive (symptom-guided)
IMPACT Trial
2018 · NEJM · AECOPD
Does triple therapy (ICS/LABA/LAMA) reduce exacerbations vs dual therapy in symptomatic COPD?
N=10,355 with symptomatic COPD and ≥1 exacerbation in prior year. Triple therapy (FF/UMEC/VI) reduced moderate/severe exacerbations vs dual LABA/LAMA. Pneumonia risk increased with ICS. Conclusion: Supports ICS addition in exacerbation-prone patients, especially with elevated blood eosinophil counts.
Positive for high-risk patients
UPLIFT Trial
2008 · NEJM · AECOPD
Does tiotropium slow lung function decline and reduce exacerbations in COPD?
N=5,993 with COPD (GOLD II–IV) over 4 years. Tiotropium 18 mcg daily reduced exacerbations and hospitalizations and improved quality of life, but did not significantly slow FEV₁ decline. Conclusion: Established LAMA as a cornerstone of COPD maintenance therapy. Does not reverse established airflow obstruction.
Positive for exacerbation prevention
Albert et al. Azithromycin COPD Trial
2011 · NEJM · AECOPD
Does daily azithromycin reduce COPD exacerbations?
N=1,142 COPD patients at risk for exacerbations. Azithromycin 250 mg daily for 1 year reduced exacerbation frequency (1.48 vs 1.83/year). Hearing loss risk identified. Conclusion: Maintenance azithromycin for exacerbation-prone COPD. Exclude patients with resting tachycardia or prolonged QTc. Not for acute treatment.
Positive (with caveats)
REDUCE Trial
2013 · JAMA · AECOPD
Is 5-day prednisone non-inferior to 14-day course for AECOPD?
N=314 hospitalized with AECOPD. Prednisone 40 mg/day for 5 days was noninferior to 14 days for re-exacerbation at 6 months, with fewer adverse effects. Conclusion: Established 5-day steroid course as standard for AECOPD. Prednisone 40 mg ×5 days is sufficient.
5 days = 14 days -use 5 days
Turner et al. MgSO₄ in Acute Bronchospasm
1997 · Lancet · AECOPD
Does IV magnesium sulfate improve lung function in acute severe asthma/bronchospasm?
Acute severe asthma patients failing initial bronchodilators. IV MgSO₄ 1.2–2 g over 20 min improved FEV₁ and reduced hospital admission rates. Conclusion: Primary evidence is in asthma. MgSO₄ is used in AECOPD as a third-line agent for refractory bronchospasm.
Positive (asthma); extrapolated to AECOPD
Soriano et al. AECOPD Triggers
1992 · Chest · AECOPD
What are the common infectious triggers of AECOPD?
Observational study of AECOPD episodes. Bacterial triggers in ~50%, viral in ~30%, both in ~10%, no pathogen in ~30%. Conclusion: Common bacteria: H. influenzae, S. pneumoniae, M. catarrhalis. Guides empiric antibiotic selection in AECOPD.
Observational
Pulmonology, ILD & Other
ASCEND
2014 · NEJM · Pulmonology
Does pirfenidone slow disease progression in IPF?
N=555 with IPF. Pirfenidone reduced FVC decline by 50% at 52 weeks. Conclusion: First antifibrotic approved for IPF. Slows progression but doesn't cure. One of two pillars of IPF therapy.
Positive
INPULSIS
2014 · NEJM · Pulmonology
Does nintedanib slow FVC decline in IPF?
N=1,066 with IPF. Nintedanib reduced annual FVC decline by ~50%. Conclusion: Second antifibrotic for IPF alongside pirfenidone. Main side effect is diarrhea.
Positive
MIST2
2011 · NEJM · Pulmonology
Does intrapleural tPA + DNase improve drainage in complicated parapneumonic effusion?
N=210 with complicated parapneumonic effusion/empyema. Intrapleural tPA + DNase improved fluid drainage and reduced surgery referral (4% vs 16%). Conclusion: tPA 10 mg + DNase 5 mg BID through chest tube for 3 days is the protocol for organized empyema.
Positive
PANTHER-IPF
2012 · NEJM · Pulmonology
Does triple immunosuppressive therapy improve outcomes in IPF?
N=238 with IPF. Prednisone + azathioprine + NAC increased mortality and hospitalizations vs placebo. Arm stopped early for harm. Conclusion: Do NOT use steroids or immunosuppression in IPF, it causes harm. Use antifibrotics (pirfenidone or nintedanib) instead.
Negative
NLST (National Lung Screening Trial)
2011 · NEJM · Oncology / Pulmonology
Does low-dose CT screening reduce lung cancer mortality?
N=53,454 high-risk adults (≥30 pack-years, age 55–74). Annual low-dose CT reduced lung cancer mortality by 20% vs chest X-ray. Conclusion: Established LDCT screening for lung cancer. Current criteria: age 50–80, ≥20 pack-years, smoked within 15 years.
Positive
Post-Cardiac Arrest
TTM-2 Trial
2021 · NEJM · Post-Cardiac Arrest
Does targeted hypothermia (33°C) reduce mortality vs targeted normothermia (37.5°C) post-arrest?
N=1,861 with out-of-hospital cardiac arrest and coma. No difference in 6-month mortality (50% vs 48%) or neurological outcome between 33°C and normothermia. Conclusion: Supersedes TTM-1 (2013). Fever prevention ≤37.7°C is the current standard. Active cooling to 33°C is no longer required.
Normothermia non-inferior -major practice change
Kilgannon et al. Hyperoxia Post-Arrest
2010 · JAMA · Post-Cardiac Arrest
Is arterial hyperoxia associated with worse outcomes after cardiac arrest?
N=6,326 post-cardiac arrest ICU patients (observational). In-hospital mortality was higher with hyperoxia (PaO₂ >300) vs normoxia, 63% vs 45%. Conclusion: Target SpO₂ 94–98% post-ROSC. Titrate FiO₂ down, do not leave on 100% O₂.
Avoid hyperoxia post-arrest
Status Epilepticus
RAMPART Trial
2012 · NEJM · Status Epilepticus
Is IM midazolam non-inferior to IV lorazepam for prehospital status epilepticus?
N=893 with prehospital status epilepticus. IM midazolam 10 mg was noninferior to IV lorazepam 4 mg, with more patients seizure-free on ED arrival (73% vs 63%) due to faster administration. Conclusion: IM route is faster when no IV access. Supports IM/IN midazolam as first-line in the community setting.
IM midazolam preferred prehospital
ESETT Trial
2019 · NEJM · Status Epilepticus
Which second-line agent is most effective for benzodiazepine-refractory status epilepticus?
N=384 with established status epilepticus after benzodiazepines. Levetiracetam 4,500 mg, fosphenytoin 20 mg PE/kg, and valproate 40 mg/kg were all equally effective (~46% seizure cessation). Conclusion: All three are acceptable second-line agents. Choice should be guided by comorbidities and side effect profile.
Neutral -all equivalent
Neurology, Stroke
NINDS tPA Trial
1995 · NEJM · Neurology
Does IV alteplase improve outcomes in acute ischemic stroke?
N=624 with acute ischemic stroke within 3 hours. IV alteplase 0.9 mg/kg resulted in 30% more patients with minimal or no disability at 3 months. ICH rate 6.4% vs 0.6%. Conclusion: Established the 3-hour window for IV tPA. Later ECASS-III extended to 4.5 hours. Time is brain.
Landmark Positive -tPA changed stroke care
MR CLEAN Trial
2015 · NEJM · Neurology
Does thrombectomy improve outcomes in large vessel occlusion stroke?
N=500 with acute ischemic stroke and proximal anterior circulation occlusion within 6 hours. Thrombectomy increased functional independence by 13.5% (NNT=7.4). Conclusion: First of five 2015 thrombectomy trials that established mechanical thrombectomy as standard of care for LVO stroke.
Landmark Positive -thrombectomy standard for LVO
ECASS III
2008 · NEJM · Neurology
Is IV tPA effective for acute ischemic stroke in the 3-4.5 hour window?
N=821 with acute ischemic stroke randomized to alteplase vs placebo within 3–4.5h of symptom onset. Alteplase improved functional outcome at 90 days. Conclusion: Extended the IV tPA treatment window from 3 hours to 4.5 hours, now the standard time cutoff worldwide.
Positive
DAWN Trial
2018 · NEJM · Neurology
Does thrombectomy benefit LVO stroke patients 6-24h with clinical-imaging mismatch?
N=206 with LVO stroke 6–24h and clinical-core mismatch (NIHSS ≥10 with small infarct core). Thrombectomy dramatically improved functional independence (mRS 0–2: 49% vs 13%). Conclusion: Extended the thrombectomy window from 6h to 24h for selected patients with mismatch on perfusion imaging.
Positive
DEFUSE-3
2018 · NEJM · Neurology
Does thrombectomy improve outcomes in LVO stroke 6-16h with perfusion mismatch?
N=182 with anterior LVO stroke 6–16h and perfusion mismatch on CT/MRI. Thrombectomy significantly improved functional independence; trial stopped early for efficacy. Conclusion: Together with DAWN, established perfusion imaging-based selection for late-window thrombectomy up to 16 hours.
Positive
GI & Hepatology
TRIGGER Trial
2015 · Lancet · Upper GI Bleed
Does liberal vs restrictive transfusion affect outcomes in upper GI bleed?
N=936 with acute upper GI bleed. No difference in 28-day mortality between liberal (Hb 9) and restrictive (Hb 7) transfusion thresholds; trend toward worse outcomes with liberal strategy in liver disease. Conclusion: Restrictive transfusion (Hb ≥7) is preferred in UGIB, fewer rebleeds, possibly via reduced portal pressure.
Restrictive strategy preferred
RFHE Trial (Rifaximin in Hepatic Encephalopathy)
2010 · NEJM · Hepatic Encephalopathy
Does rifaximin prevent recurrence of overt hepatic encephalopathy?
N=299 in hepatic encephalopathy remission (most on background lactulose). Rifaximin 550 mg BID reduced HE recurrence (22% vs 46%) and HE-related hospitalization. Conclusion: Rifaximin + lactulose is standard maintenance therapy for prevention of recurrent hepatic encephalopathy.
Positive
CONFIRM Trial
2021 · NEJM · Hepatology
Does terlipressin improve outcomes in hepatorenal syndrome?
N=300 with hepatorenal syndrome-AKI. Terlipressin + albumin improved HRS reversal (32% vs 17%), though with more respiratory adverse events. Conclusion: FDA-approved terlipressin for HRS-AKI. Monitor closely for respiratory failure during treatment.
Positive
PREDESCI
2019 · Lancet · Hepatology
Do beta-blockers prevent first decompensation in cirrhosis with portal HTN but no varices?
N=201 with cirrhosis and clinically significant portal hypertension but no varices. Beta-blockers reduced first decompensation events. Conclusion: Supports early beta-blocker use in compensated cirrhosis with elevated HVPG, even before varices develop.
Positive
PANTER
2010 · NEJM · Surgery / GI
Is a step-up approach superior to primary open necrosectomy for infected necrotizing pancreatitis?
N=88 with infected necrotizing pancreatitis. Step-up approach (percutaneous drain → necrosectomy if fails) reduced major complications (40% vs 69%) and new-onset organ failure. Conclusion: Step-up approach is standard of care, drain first, operate only if drainage fails.
Positive
PONCHO
2015 · Lancet · Surgery / GI
Should cholecystectomy be performed during same admission for mild gallstone pancreatitis?
N=266 with mild gallstone pancreatitis. Same-admission cholecystectomy reduced readmission for biliary events (5% vs 17%). Conclusion: Perform cholecystectomy before discharge in mild gallstone pancreatitis to prevent recurrent biliary events.
Positive
Diabetes & Endocrine
DCCT Trial
1993 · NEJM · Diabetes
Does intensive glucose control reduce microvascular complications in T1DM?
N=1,441 with type 1 diabetes. Intensive insulin (A1c ~7%) reduced retinopathy by 76%, nephropathy by 50%, and neuropathy by 60% vs conventional therapy (A1c ~9%). Conclusion: Foundation for the A1c <7% target. Follow-up EDIC study showed early tight control benefits lasted decades ("metabolic memory").
Landmark Positive
UKPDS 34
1998 · Lancet · Diabetes
Does metformin improve outcomes in overweight T2DM?
N=1,704 overweight patients with newly diagnosed T2DM. Metformin reduced all-cause mortality by 36% and diabetes-related death by 42% vs conventional therapy, superior to sulfonylurea/insulin despite similar A1c. Conclusion: Established metformin as first-line therapy for T2DM with benefits beyond glucose lowering.
Landmark Positive -metformin first-line
EMPA-REG OUTCOME
2015 · NEJM · Diabetes / HF
Does empagliflozin reduce CV events in T2DM with CVD?
N=7,020 with T2DM and established CVD. Empagliflozin reduced MACE by 14%, CV death by 38%, HF hospitalization by 35%, and slowed eGFR decline by 39%. Conclusion: First SGLT2i CV outcome trial, launched the SGLT2i era for cardio-renal protection beyond glucose lowering.
Landmark Positive -SGLT2i revolution
DPP (Diabetes Prevention Program)
2002 · NEJM · Diabetes Prevention
Can lifestyle or metformin prevent T2DM?
N=3,234 overweight adults with impaired glucose tolerance. Intensive lifestyle (7% weight loss + 150 min/wk exercise) reduced T2DM incidence by 58%; metformin by 31%. Conclusion: Lifestyle intervention is the most effective strategy for diabetes prevention, superior to metformin alone.
Landmark Positive
LEADER Trial
2016 · NEJM · Diabetes / Cardiology
Does liraglutide reduce CV events in T2DM?
N=9,340 with T2DM at high CV risk. Liraglutide (GLP-1 RA) reduced MACE by 13% and CV death by 22%. Conclusion: Established GLP-1 RAs as cardioprotective in T2DM with CVD, now recommended alongside SGLT2i for atherosclerotic CVD.
Positive -GLP-1 RA cardioprotective
ADA Standards of Care 2026
2026 · Diabetes Care · DKA / Glucose
What are the recommended targets for inpatient glycemic management?
Targets: 140–180 mg/dL (ICU), 100–180 mg/dL (non-ICU). Initiate insulin at BG ≥180 × 2. 2026 updates: perioperative A1c <8% goal, CGM recommended at diagnosis, GLP-1 RA approved for T1DM with obesity. Conclusion: Comprehensive guideline for inpatient and outpatient diabetes care with new CKM framework.
Guideline
ADVANCE Trial
2008 · NEJM · Diabetes
Does intensive glucose control reduce events in T2DM?
N=11,140 with T2DM and high vascular risk. Intensive gliclazide-based therapy (target A1c ≤6.5%) reduced nephropathy by 21% but showed no significant reduction in macrovascular events or mortality. Conclusion: Gentler intensive control is safe but only reduces renal events, A1c 6.5–7% is the optimal target zone.
Mixed -microvascular but not macrovascular
ACCORD Trial
2008 · NEJM · Diabetes
Does very intensive A1c lowering reduce CV events in T2DM?
N=10,251 with T2DM and high CV risk. Intensive arm (target A1c <6%) stopped early due to 22% increase in all-cause mortality with more hypoglycemia and weight gain. Conclusion: Very tight A1c (<6.5%) is harmful in high-risk T2DM. Individualize targets: <7% for most, <8% for elderly/frail.
Negative -increased mortality
RABBIT 2
2007 · Diabetes Care · Endocrinology
Is basal-bolus insulin superior to sliding scale in hospitalized T2DM?
N=130 T2DM surgical patients. Basal-bolus insulin (glargine + glulisine) achieved better glucose control (BG <140: 66% vs 38%) with no increase in hypoglycemia vs sliding scale alone. Conclusion: Sliding scale alone is inferior, always use basal-bolus regimen for inpatient diabetes management.
Positive
SURMOUNT-1
2022 · NEJM · Endocrinology / Obesity
Does tirzepatide reduce body weight in obesity without diabetes?
N=2,539 adults with BMI ≥30 (or ≥27 with comorbidity) without diabetes. Tirzepatide reduced body weight by up to 22.5% at 72 weeks. Conclusion: Unprecedented weight loss with a non-surgical intervention, established tirzepatide as a leading obesity therapy.
Positive
SURPASS-2
2021 · NEJM · Endocrinology
Is tirzepatide superior to semaglutide in T2DM?
N=1,879 with T2DM. Tirzepatide (dual GIP/GLP-1 agonist) was superior to semaglutide with A1c reduction up to 2.5% and weight loss up to 12.4 kg. Conclusion: Tirzepatide is the most potent glucose-lowering and weight-loss agent available for T2DM.
Positive
Nephrology
DAPA-CKD
2020 · NEJM · Nephrology
Does dapagliflozin slow CKD progression regardless of diabetes status?
N=4,304 with eGFR 25–75 and albuminuria. Dapagliflozin reduced sustained GFR decline/ESKD/renal death by 39%, with benefit regardless of diabetes status. Conclusion: SGLT2i is now standard of care for CKD with albuminuria, diabetic or not.
Positive
EMPA-KIDNEY
2022 · NEJM · Nephrology
Does empagliflozin improve kidney outcomes in broad CKD population?
N=6,609 with eGFR 20–45 or 45–90 with albuminuria. Empagliflozin reduced kidney progression and CV death by 28%. Conclusion: Confirmed SGLT2i class effect in CKD, benefits extend even to patients with low GFR.
Positive
FIDELIO-DKD
2020 · NEJM · Nephrology
Does finerenone improve kidney outcomes in diabetic kidney disease?
N=5,734 with T2DM and CKD on max RAAS blockade. Finerenone (non-steroidal MRA) reduced kidney failure and sustained GFR decline by 18%, with less hyperkalemia than spironolactone. Conclusion: Add finerenone on top of ACEi/ARB for diabetic kidney disease for additional renal protection.
Positive
FIGARO-DKD
2021 · NEJM · Nephrology
Does finerenone reduce cardiovascular events in T2DM with CKD?
N=7,437 with T2DM and CKD stages 1–4. Finerenone reduced CV death/MI/stroke/HF hospitalization by 13%. Conclusion: With FIDELIO, established finerenone as a key agent for cardiorenal protection in diabetic CKD.
Positive
SHARP Trial (CKD)
2011 · Lancet · Nephrology
Does simvastatin + ezetimibe reduce CV events in CKD?
N=9,270 CKD patients (not on dialysis). Simvastatin/ezetimibe reduced major atherosclerotic events by 17%. No benefit seen in dialysis patients. Conclusion: Statins benefit CKD patients NOT yet on dialysis. Once on dialysis, do not start statins.
Positive
IDEAL Trial
2010 · NEJM · Nephrology
Does early dialysis initiation improve survival compared to late start?
N=828 CKD patients. Starting dialysis at eGFR 10–14 (early) vs 5–7 (late) showed no difference in mortality. Conclusion: No benefit to early dialysis start, initiate based on symptoms, not GFR number alone.
Neutral
TEMPO 3:3
2012 · NEJM · Nephrology
Does tolvaptan slow disease progression in ADPKD?
N=1,445 with early ADPKD. Tolvaptan slowed kidney growth and GFR decline over 3 years. Conclusion: Only disease-modifying therapy for ADPKD. Monitor LFTs for hepatotoxicity risk.
Positive
ONTARGET
2008 · NEJM · Nephrology / Cardiology
Does dual RAAS blockade with ACEi + ARB improve cardiovascular outcomes?
N=25,620 high CV risk patients. Telmisartan + ramipril combo increased renal adverse events (hyperkalemia, AKI) without CV benefit vs either agent alone. Conclusion: Do NOT combine ACEi + ARB, more harm, no benefit.
Negative
VA NEPHRON-D
2013 · NEJM · Nephrology
Does dual RAAS blockade improve outcomes in diabetic nephropathy?
N=1,448 with T2DM and proteinuria. Losartan + lisinopril stopped early, combo increased hyperkalemia and AKI without benefit. Conclusion: Do NOT combine ACEi + ARB for diabetic nephropathy.
Negative
CHOIR
2006 · NEJM · Nephrology
Does targeting higher Hgb with EPO improve outcomes in CKD?
N=1,432 CKD patients on epoetin. Targeting Hgb 13.5 vs 11.3 increased composite CV events. Conclusion: With TREAT, established that ESA target should be 10–11.5 g/dL, not higher.
Negative
TREAT Trial
2009 · NEJM · Nephrology
Does targeting higher hemoglobin with darbepoetin improve outcomes in CKD anemia?
N=4,038 with T2DM, CKD, and anemia. Darbepoetin targeting Hgb 13 showed no benefit and increased stroke risk. Conclusion: Do not target Hgb >11–12 with ESAs, higher targets cause more harm.
Negative
Nephrology, Contrast-Induced AKI
PRESERVE Trial
2018 · NEJM · Nephrology / CI-AKI
Do IV sodium bicarbonate or oral N-acetylcysteine prevent contrast-induced kidney injury?
N=4,993 high-risk patients with stage 3 or 4 CKD (plus diabetes for most) undergoing angiography. 2x2 factorial. Neither IV sodium bicarbonate (vs normal saline) nor oral NAC (vs placebo) reduced death, dialysis, or persistent Cr rise at 90 days. Conclusion: Definitive trial ending NAC and bicarbonate in CI-AKI prophylaxis. Current practice is IV isotonic saline only.
Negative, killed NAC and bicarbonate
AMACING Trial
2017 · Lancet · Nephrology / CI-AKI
Is no prophylaxis noninferior to IV saline for preventing contrast-induced AKI in moderate-risk CKD?
N=660 with eGFR 30 to 59 scheduled for elective contrast imaging (mostly IV). No prophylaxis vs IV 0.9% saline 1 mL/kg/hr. CI-AKI: 2.6% vs 2.7% (noninferior). No difference in dialysis, 35-day Cr, or mortality. Fluid-overload complications only in the saline arm. Conclusion: Supports the modern reframe that routine hydration in moderate-risk patients for IV contrast is unnecessary.
Noninferior, challenges routine hydration
ACT Trial
2011 · Circulation · Nephrology / CI-AKI
Does oral N-acetylcysteine prevent contrast-induced nephropathy?
N=2,308 undergoing coronary or peripheral angiography with at least one CI-AKI risk factor. Oral NAC 1,200 mg BID x 2 days vs placebo on IV saline background. CI-AKI: 12.7% vs 12.7%. No effect on 30-day death or dialysis. Conclusion: First large well-powered trial to disprove NAC benefit. Earlier "positive" studies likely confounded by NAC artifactually lowering serum Cr via assay interference.
Negative, NAC does not prevent CI-AKI
Rheumatology
RAVE Trial
2010 · NEJM · Rheumatology
Is rituximab noninferior to cyclophosphamide for ANCA vasculitis induction?
N=197 with GPA or MPA. Rituximab was noninferior to cyclophosphamide for remission induction and superior in relapsing disease. Conclusion: Rituximab is now first-line for ANCA vasculitis induction and maintenance therapy.
Positive
ORAL Surveillance
2022 · NEJM · Rheumatology
Is tofacitinib cardiovascularly safe in RA patients with CV risk?
N=4,362 RA patients >50yo with CV risk factors. Tofacitinib had higher rates of MACE and malignancy compared to TNF inhibitor. Conclusion: FDA black box warning on all JAK inhibitors, use only after TNFi failure.
Negative
CARES Trial
2018 · NEJM · Rheumatology
Is febuxostat cardiovascularly safe in gout patients with CV disease?
N=6,190 gout patients with CV disease. Febuxostat had higher CV and all-cause mortality compared to allopurinol. Conclusion: FDA black box warning on febuxostat. Use allopurinol first-line for gout.
Negative
Infectious Disease
START Trial (INSIGHT-START)
2015 · NEJM · HIV
Should ART start immediately regardless of CD4?
N=4,685 HIV-positive adults with CD4 >500. Immediate ART reduced serious AIDS events and death by 57%; stopped early for benefit. Conclusion: All HIV-positive patients should start ART immediately regardless of CD4 count.
Landmark Positive -treat all HIV immediately
HPTN 052 Trial
2011 · NEJM · HIV
Does early ART reduce HIV transmission?
N=1,763 serodiscordant couples (CD4 350–550). Early ART reduced HIV transmission to partners by 96%. Conclusion: Foundation for U=U (Undetectable = Untransmittable), early treatment prevents transmission.
Landmark Positive -U=U foundation
ACTG 076 Trial
1994 · NEJM · HIV
Does zidovudine reduce vertical HIV transmission?
N=477 HIV-positive pregnant women and infants. Zidovudine during pregnancy, labor, and neonatal prophylaxis reduced vertical transmission by 67.5% (25.5% → 8.3%). Conclusion: Foundation for modern PMTCT (prevention of mother-to-child transmission) protocols.
Landmark Positive -PMTCT became standard
POET Trial
2019 · NEJM · Infectious Disease
Can stable endocarditis switch from IV to oral antibiotics?
N=400 with stable left-sided endocarditis after ≥10 days IV therapy. Oral switch was noninferior (12.1% vs 12.0% composite endpoint). Conclusion: Stable left-sided endocarditis can safely switch to oral antibiotics after initial IV course.
Positive -oral step-down safe
OVIVA Trial
2019 · NEJM · Infectious Disease
Are oral antibiotics noninferior to IV for bone/joint infections?
N=1,054 adults with bone and joint infections. Oral antibiotics were noninferior to IV (14.6% vs 14.1% treatment failure at 1 year). Conclusion: Oral antibiotics are sufficient for bone/joint infections, IV-to-oral switch is safe.
Positive -oral sufficient
ACORN Trial
2023 · JAMA · Infectious Disease / Nephrotoxicity
Does cefepime cause less AKI than pip-tazo when combined with vancomycin?
N=2,511 hospitalized adults needing an antipseudomonal beta-lactam, about 78% also on vancomycin. Primary endpoint (highest stage of AKI or death at day 14) showed NO difference (OR 0.95, 95% CI 0.80-1.13, p=0.56). Cefepime caused more neurologic dysfunction (20.8% vs 17.3%). Conclusion: the only RCT to date does not support the older observational pip-tazo plus vancomycin AKI signal. If you prefer cefepime, prefer it for anaerobic sparing, not for the kidneys, and watch for cefepime neurotoxicity in AKI and the elderly.
Neutral on AKI -cefepime had more neurotoxicity
SMART Trial
2006 · NEJM · HIV
Can ART be safely interrupted based on CD4?
N=5,472 HIV-positive adults with CD4 >350 on ART. CD4-guided ART interruption increased opportunistic disease 2.6-fold and increased all-cause mortality. Conclusion: ART must be lifelong, treatment interruptions are dangerous.
Negative -never stop ART
MODIFY I/II
2017 · NEJM · Infectious Disease
Does bezlotoxumab prevent C. diff recurrence?
N=2,655 with C. difficile infection. Bezlotoxumab (anti-toxin B antibody) reduced recurrence from 27% to 17%. Conclusion: Single IV dose bezlotoxumab prevents C. diff recurrence in high-risk patients.
Positive
STOP-IT
2015 · NEJM · Infectious Disease / Surgery
Are short-course antibiotics sufficient for intra-abdominal infection with adequate source control?
N=518 with intra-abdominal infection and adequate source control. 4 days of antibiotics was noninferior to treatment until clinical resolution. Conclusion: 4 days is enough after adequate source control, stop antibiotics early.
Positive
COVID-19
RECOVERY Dexamethasone Trial
2021 · NEJM · COVID-19
Does dexamethasone reduce mortality in hospitalized COVID-19?
N=6,425 hospitalized with COVID-19. Dexamethasone 6 mg daily × 10 days reduced 28-day mortality in patients on oxygen (23.3% vs 26.2%) and ventilated patients (29.3% vs 41.4%). No benefit without O₂. Conclusion: First proven mortality benefit in COVID-19, dexamethasone became standard of care for hypoxic patients.
Landmark Positive
BNT162b2 Pfizer-BioNTech Vaccine Trial
2020 · NEJM · COVID-19
Is the BNT162b2 mRNA vaccine effective against COVID-19?
N=43,548 adults ≥16 years. BNT162b2 mRNA vaccine (2 doses, 21 days apart) showed 95% efficacy against symptomatic COVID-19 and 100% efficacy against severe disease. Conclusion: First mRNA vaccine authorized for human use, ushered in the mRNA vaccine era.
Landmark Positive -95% efficacy
ACTT-1 Trial
2020 · NEJM · COVID-19
Does remdesivir improve recovery in hospitalized COVID-19?
N=1,062 hospitalized with COVID-19 and lower respiratory tract infection. Remdesivir shortened median recovery time from 15 to 10 days (31% faster) with a trend toward lower mortality. Conclusion: First antiviral with proven benefit in COVID-19 hospitalization.
Positive -shortens recovery
Oncology
IRIS Trial -Imatinib for CML
2006 · NEJM · Oncology
Is imatinib superior to interferon for CML?
N=1,106 with newly diagnosed chronic-phase CML. Imatinib achieved complete cytogenetic response in 76% vs 15% with interferon; estimated 5-year OS 89%. Conclusion: Imatinib turned CML from a fatal disease into a chronic manageable condition, paradigm for targeted therapy.
Landmark Positive -targeted therapy
HERA Trial -Trastuzumab for HER2+ Breast Cancer
2005 · NEJM · Oncology
Does trastuzumab improve outcomes in HER2+ breast cancer?
N=5,102 with HER2-positive early breast cancer. 1 year of adjuvant trastuzumab reduced recurrence by 46% and improved overall survival. Conclusion: Established 1 year of adjuvant trastuzumab as standard of care for HER2+ breast cancer.
Landmark Positive
KEYNOTE-024 Trial
2016 · NEJM · Oncology
Is pembrolizumab better than chemo in high PD-L1 NSCLC?
N=305 with untreated metastatic NSCLC and PD-L1 ≥50%. Pembrolizumab improved PFS (10.3 vs 6.0 months), OS, and response rate (44.8% vs 27.8%). Conclusion: Pembrolizumab monotherapy became standard first-line for high PD-L1 NSCLC, the immunotherapy era.
Positive -immunotherapy era
CLEOPATRA Trial
2012 · NEJM · Oncology
Does adding pertuzumab to trastuzumab improve metastatic HER2+ breast cancer?
N=808 with HER2-positive metastatic breast cancer. Pertuzumab + trastuzumab + docetaxel improved median OS by 15.7 months (56.5 vs 40.8 months). Conclusion: Dual HER2 blockade became standard first-line for HER2+ metastatic breast cancer.
Positive -dual HER2 blockade
FLAURA Trial
2018 · NEJM · Oncology
Is osimertinib superior to first-gen EGFR TKIs?
N=556 with untreated EGFR-mutant advanced NSCLC. Osimertinib improved median PFS (18.9 vs 10.2 months) and OS (38.6 vs 31.8 months) vs standard EGFR TKI. Conclusion: Osimertinib is the preferred first-line EGFR TKI for advanced NSCLC.
Positive -osimertinib first-line
SHARP Trial -Sorafenib for HCC
2008 · NEJM · Oncology / Hepatology
Does sorafenib improve survival in advanced HCC?
N=602 with advanced HCC (Child-Pugh A). Sorafenib improved median OS (10.7 vs 7.9 months) and time to progression. Conclusion: First systemic therapy proven to improve survival in HCC, was standard of care until IMbrave150.
Positive -first systemic HCC therapy
IMbrave150 Trial
2020 · NEJM · Oncology / Hepatology
Is atezolizumab + bevacizumab superior to sorafenib in HCC?
N=501 with unresectable HCC, treatment-naive. Atezolizumab + bevacizumab improved 12-month OS (67.2% vs 54.6%) and median PFS (6.8 vs 4.3 months) vs sorafenib. Conclusion: New standard first-line for advanced HCC, immunotherapy + anti-VEGF replaced sorafenib.
Positive -new first-line for HCC
Hematology & Transfusion
TRICC Trial
1999 · NEJM · Transfusion / ICU
Restrictive vs liberal transfusion in critically ill patients?
N=838 euvolemic critically ill patients with Hgb <9. Restrictive strategy (transfuse if Hgb <7, maintain 7–9) was noninferior to liberal (transfuse if <10, maintain 10–12) with lower in-hospital mortality in less acutely ill patients. Conclusion: Established Hgb 7 g/dL trigger as standard in most ICU patients.
Positive -restrictive became standard
Villanueva Restrictive Transfusion Trial
2013 · NEJM · GI Bleeding
Restrictive vs liberal transfusion in acute upper GI bleeding?
N=921 with acute upper GI bleeding. Restrictive transfusion (Hgb <7) reduced 45-day mortality (5% vs 9%), rebleeding, and complications compared to liberal (Hgb <9). Conclusion: Restrictive transfusion actually improves GI bleed outcomes, transfuse at Hgb <7.
Positive -restrictive is BETTER in GI bleed
CLOT Trial
2003 · NEJM · Hematology
Is LMWH better than warfarin for cancer-associated VTE?
N=676 with cancer and acute VTE. Dalteparin (LMWH) × 6 months reduced recurrent VTE by 52% (9% vs 17%) compared to dalteparin bridging then warfarin. Conclusion: LMWH became standard for cancer-associated VTE (now largely replaced by DOACs).
Positive -LMWH beat warfarin
EINSTEIN-DVT/PE
2010 · NEJM · Hematology / VTE
Is rivaroxaban effective for VTE treatment?
N=8,281 (DVT + PE combined). Rivaroxaban was noninferior to enoxaparin/warfarin with less major bleeding. Conclusion: Established rivaroxaban as oral-only VTE treatment without need for heparin bridging.
Positive
AMPLIFY
2013 · NEJM · Hematology / VTE
Is apixaban effective for VTE treatment?
N=5,395 with VTE. Apixaban was noninferior to enoxaparin/warfarin with 69% less major bleeding. Conclusion: Apixaban has the best bleeding profile among DOACs for VTE treatment.
Positive
PEITHO
2014 · NEJM · Pulmonary / VTE
Does thrombolysis improve outcomes in Category C3 PE (formerly submassive)?
N=1,006 with intermediate-risk PE (RV dysfunction + troponin). Tenecteplase reduced hemodynamic decompensation (1.6% vs 5%) but increased major bleeding (11.5% vs 2.4%). Conclusion: Do not routinely lyse Category C3 PE, reserve thrombolysis for hemodynamic deterioration.
Neutral
PROPPR
2015 · JAMA · Hematology / Trauma
What is the optimal massive transfusion ratio?
N=680 severely injured trauma patients. 1:1:1 (plasma:platelets:RBC) achieved better hemostasis and fewer deaths from exsanguination at 24h compared to 1:1:2. Conclusion: Supports balanced 1:1:1 ratio in massive transfusion protocols.
Positive
TRICS-III
2017 · NEJM · Hematology
Is restrictive transfusion safe in cardiac surgery?
N=5,243 undergoing cardiac surgery. Restrictive transfusion (Hgb <7.5) was noninferior to liberal (<9.5) for death/MI/stroke/renal failure. Conclusion: Even cardiac surgery patients do not need liberal transfusion thresholds.
Positive
HERCULES
2019 · NEJM · Hematology
Does caplacizumab improve outcomes in acquired TTP?
N=145 with acquired TTP. Caplacizumab (anti-vWF nanobody) + plasma exchange achieved faster platelet normalization and fewer TTP-related deaths and recurrences. Conclusion: Caplacizumab added to standard TTP treatment (PEX + steroids + rituximab).
Positive
MSH Trial (Multicenter Study of Hydroxyurea)
1995 · NEJM · Hematology
Does hydroxyurea reduce painful crises in sickle cell disease?
N=299 adults with severe SCD. Hydroxyurea reduced painful crises by 44%, ACS by 50%, and transfusions by 67%; stopped early for benefit. Conclusion: Established hydroxyurea as standard of care for sickle cell disease.
Positive
SUSTAIN Trial
2017 · NEJM · Hematology
Does crizanlizumab reduce vaso-occlusive crises in SCD?
N=198 with sickle cell disease. Crizanlizumab (anti-P-selectin antibody) reduced vaso-occlusive crises by 45% vs placebo. Conclusion: First targeted biologic therapy for sickle cell disease prevention.
Positive
VIALE-A
2020 · NEJM · Hematology / Oncology
Does venetoclax + azacitidine improve survival in older/unfit AML patients?
N=431 treatment-naive AML patients unfit for intensive chemo. Venetoclax + azacitidine improved OS (14.7 vs 9.6 months) and CR rate (66% vs 28%). Conclusion: Standard of care for older/unfit AML patients who cannot tolerate intensive induction chemotherapy.
Positive
IV Fluids & Resuscitation
SALT-ED Trial
2018 · NEJM · IV Fluids
Balanced crystalloids vs normal saline in non-critically ill adults?
N=13,347 non-critically ill adults receiving IV fluids in the ED. Balanced crystalloid (LR or Plasma-Lyte) had lower major adverse kidney events at 30 days (4.7% vs 5.6%) vs normal saline. Conclusion: Balanced crystalloids preferred over normal saline for IV fluid resuscitation.
Positive -balanced crystalloids preferred
🌟 2025 Practice-Changing Trials
Beta-Blocker Post-MI Meta-Analysis (5-Trial IPD)
2025 · NEJM · Cardiology
Do beta-blockers improve outcomes after MI with preserved EF?
N=17,801 from 5 trials (REBOOT, REDUCE-AMI, BETAMI, DANBLOCK, CAPITAL-RCT). Patients with recent MI and preserved EF (≥50%). No reduction in death, recurrent MI, or heart failure at 3.6 years. Conclusion: Definitively ends reflexive beta-blocker prescribing post-MI with preserved EF. Beta-blockers still benefit patients with reduced EF (40–49%).
No benefit,40-year paradigm retired
SUMMIT Trial
2025 · NEJM · Heart Failure / Endocrinology
Does tirzepatide improve outcomes in HFpEF with obesity?
N=731 with HFpEF (EF ≥50%), BMI ≥30, NYHA II–IV. Tirzepatide reduced CV death or worsening HF by 38% and cut worsening HF events by 46%. Improved quality of life scores. Conclusion: Dual GIP/GLP-1 agonism is disease-modifying for obese HFpEF, historically few effective treatments existed for this phenotype.
Positive,46% reduction in worsening HF
SOUL Trial
2025 · NEJM · Endocrinology / Cardiology
Does oral semaglutide reduce CV events in T2DM with ASCVD or CKD?
N=9,650 aged ≥50 with T2DM and established ASCVD, CKD, or both. Oral semaglutide 14 mg daily reduced major CV events (MACE) by 14% and nonfatal MI by 26% vs placebo. Conclusion: First oral GLP-1 RA to demonstrate CV superiority. Benefit seen regardless of background SGLT2i use. Provides an oral alternative to injectable semaglutide.
Positive, first oral GLP-1 RA with CV superiority
SURMOUNT-5
2025 · NEJM · Endocrinology
How does tirzepatide compare to semaglutide for obesity?
Adults with BMI ≥30 or overweight with comorbidities. First head-to-head comparison over 72 weeks. Tirzepatide achieved 20.2% weight loss vs 13.7% with semaglutide. Greater waist circumference reduction (18.4 vs 13.0 cm). Conclusion: Tirzepatide is consistently superior to semaglutide for weight loss. Dual incretin agonism (GIP + GLP-1) outperforms GLP-1 alone.
Positive, tirzepatide superior (-20% vs -14%)
ESSENCE Trial
2025 · NEJM · Gastroenterology / Hepatology
Does semaglutide resolve MASH and improve liver fibrosis?
N=1,197 with biopsy-confirmed MASH and fibrosis (F2–F3). Semaglutide 2.4 mg SC weekly achieved MASH resolution in 63% vs 34% placebo. Fibrosis improved in 37% vs 22%. Weight loss 10.5% vs 2.0%. Conclusion: First GLP-1 RA with Phase 3 data showing both histologic MASH resolution AND fibrosis improvement. Granted FDA Priority Review.
Does CRT-guided personalized resuscitation improve outcomes in septic shock?
N=1,467 with early septic shock across 86 centers in 19 countries. CRT-guided resuscitation led to less fluid (250 mL less at 6h), more vital-support-free days, and better composite outcomes vs usual care. 28-day mortality was similar. Conclusion: Capillary refill time is a valid bedside resuscitation target. Personalized fluid management reduces organ support without increasing mortality.
Positive, reduced organ support duration
CloCeBa Trial
2025 · Lancet · Infectious Disease
Is cefazolin non-inferior to cloxacillin for MSSA bacteremia?
N=315 with MSSA bacteremia at 21 hospitals. Cefazolin IV q8h was non-inferior to cloxacillin IV q4–6h (75% vs 74% clinical success at day 90). AKI dramatically lower with cefazolin (1% vs 12%). Serious adverse events nearly halved (15% vs 27%). Conclusion: First RCT confirming cefazolin as non-inferior with far better safety. Supports cefazolin as preferred first-line for MSSA bacteremia.
Positive, cefazolin non-inferior, far safer (AKI 1% vs 12%)
OCEAN Trial
2025 · NEJM · Cardiology
Is continued anticoagulation necessary after successful AF ablation?
N=1,284 with successful AF ablation ≥1 year prior and CHA₂DS₂-VASc ≥1. Rivaroxaban 15 mg vs aspirin over 3 years. Stroke/systemic embolism was extremely rare on both therapies. Rivaroxaban increased major bleeding (1.6% vs 0.6%) with no embolic benefit. Trial stopped early for futility. Conclusion: Challenges indefinite anticoagulation after successful AF ablation. Aspirin may be sufficient in low-event-rate post-ablation patients.
Neutral, rivaroxaban no better than aspirin post-ablation
DIGIT-HF
2025 · NEJM · Heart Failure
Does digitoxin added to GDMT improve outcomes in advanced HFrEF?
N=1,240 with advanced HFrEF (LVEF ≤40%, NYHA III–IV) already on background GDMT. Digitoxin reduced the composite of death and HF hospitalization by 18% over 3 years. Conclusion: Revives cardiac glycosides in the modern GDMT era. Digitoxin (not digoxin) has more predictable pharmacokinetics and requires no renal dose adjustment.
Positive,18% reduction in death + HF hospitalization
🌟 2026 Practice-Changing Trials & Guidelines
AHA/ACC Acute PE Guideline 2026
2026 · Circulation / JACC · Pulmonary / Critical Care
First comprehensive AHA/ACC PE guideline, new Category A–E classification system
First-ever AHA/ACC PE guideline with 129 recommendations from 10 societies. Replaces "massive/submassive/low-risk" with Categories A–E based on pathophysiological severity. DOACs preferred over warfarin. LMWH preferred over UFH. PERT activation for Category C–E. Systemic tPA reserved for Category E. Structured post-PE follow-up mandated. Conclusion: Paradigm shift in PE classification. New Category D captures "pre-arrest" patients previously grouped under submassive.
Guideline, paradigm shift in PE classification
HI-PEITHO
2026 · NEJM · Pulmonary / Critical Care
Does catheter-directed thrombolysis improve outcomes in intermediate-high-risk PE?
N=544 with intermediate-high-risk PE (RV dysfunction + elevated troponin) at 59 sites. Ultrasound-facilitated catheter-directed thrombolysis (low-dose alteplase 9–17 mg) reduced PE death, decompensation, and recurrence by 61% vs anticoagulation alone at 30 days. No increase in major bleeding. Conclusion: First RCT showing CDT benefit in intermediate-risk PE without the bleeding penalty of systemic tPA (PEITHO). Low-dose catheter-delivered alteplase is the key innovation.
Positive,61% reduction in decompensation, no increased bleeding
COBRRA Trial
2026 · NEJM · Hematology / Cardiology
Is apixaban safer than rivaroxaban for acute VTE?
N=2,760 with acute symptomatic PE or proximal DVT. First head-to-head comparison of apixaban vs rivaroxaban over 3 months. Apixaban cut clinically relevant bleeding by over 50% (3.3% vs 7.1%). Recurrent VTE was identical (1.0% vs 1.0%). Conclusion: Equal efficacy but far less bleeding with apixaban. The DOAC choice for VTE is no longer a coin flip, apixaban is preferred.
Positive,54% less bleeding, equal efficacy
CREST-2
2026 · NEJM · Cardiology / Vascular
Is carotid revascularization superior to intensive medical therapy for asymptomatic carotid stenosis?
N=2,485 with ≥70% asymptomatic carotid stenosis across 155 centers. Stenting significantly reduced 4-year stroke and death vs medical therapy alone (2.8% vs 6.0%). Endarterectomy did NOT reach significance (3.7% vs 5.3%). Conclusion: Carotid stenting is superior to medical therapy alone, but routine endarterectomy may not add benefit over intensive medical management in asymptomatic patients.
Positive for stenting, neutral for CEA
Surviving Sepsis Campaign 2026
2026 · Crit Care Med / Intensive Care Med · Critical Care
Updated evidence-based recommendations for sepsis and septic shock management
129 statements (46 new) by 130+ experts from 23 countries. Key changes: avoid anti-anaerobic antibiotics in low-risk; prehospital sepsis screening; peripheral vasopressors OK to start; hydrocortisone suggested for refractory shock; qSOFA replaced by NEWS/MEWS; post-sepsis follow-up mandated. Conclusion: Most significant SSC update since 2021. Antimicrobial stewardship emphasis is the biggest paradigm shift.
Does inhaled treprostinil slow disease progression in idiopathic pulmonary fibrosis?
N=593 with IPF (75% already on background antifibrotic). Inhaled treprostinil slowed FVC decline by ~65% vs placebo over 52 weeks (–50 mL vs –136 mL). Clinical worsening reduced by 29%. Benefit was additive on top of nintedanib or pirfenidone. Conclusion: First new mechanism drug for IPF beyond the existing two antifibrotics. Establishes inhaled treprostinil as the third pillar of IPF therapy.
Positive, third pillar of IPF therapy
VISIONARY Trial (Sibeprenlimab)
2026 · NEJM · Nephrology
Does anti-APRIL therapy reduce proteinuria in IgA nephropathy?
N=510 (largest Phase 3 IgAN trial ever). Sibeprenlimab (anti-APRIL monoclonal antibody) reduced proteinuria by ~50% at 9 months vs a 2% increase with placebo. Over 51% relative reduction vs placebo. Granted FDA accelerated approval. Conclusion: First targeted, disease-modifying therapy for IgA nephropathy. Unlike steroids or SGLT2i, this directly blocks the APRIL pathway driving IgAN pathogenesis.
Positive,51% proteinuria reduction, FDA approved
ADA Standards of Care 2026
2026 · Diabetes Care · DKA / Glucose
Updated ADA standards: perioperative targets, CGM, GLP-1 RA for T1DM
Key 2026 changes: Perioperative glucose target 100–180 mg/dL (A1c <8% pre-surgery). CGM recommended at diagnosis of T1DM and T2DM on insulin. GLP-1 RA expanded to T1DM as adjunct. SGLT2i + finerenone combination for diabetic CKD. BP target <120 systolic for high CV risk. New section on cancer treatment-related hyperglycemia. Conclusion: Broadest update in years, perioperative standards and CGM recommendations are the most practice-changing.
Guideline
Quick Reference
Procedures Guide
Step-by-step for the 5 core bedside procedures every resident must master. Landmarks, equipment, technique, and complications.
🩺 Central Venous Catheter
Site Selection
Site
Pros
Cons
Preferred For
Right IJ
Most commonly used. Straight path to SVC. Low PTX risk with US. Easy for right-handed operators.
Neck motion limitation. Infection risk if tracheostomy nearby.
Dialysis catheters, Swan-Ganz, general access.
Subclavian
Lowest infection rate. Most comfortable for patient. Best for long-term use.
Highest PTX risk. Non-compressible if arterial puncture. Harder with US.
Long-term access, TPN, when lower infection risk critical.
Femoral
Easiest landmark access. No PTX risk. No airway compromise.
Highest infection rate. DVT risk. Can't use for CVP monitoring (inaccurate). Limits mobility.
Consent, time-out, cap/mask/gown/gloves, full sterile drape. Position: Trendelenburg 15–20° (distends IJ). Head turned slightly contralateral. US with sterile probe cover.
Identify
IJ = lateral, round, compressible. Carotid = medial, pulsatile, non-compressible. Confirm with Doppler if unsure. Use short-axis (transverse) view for access.
Access
Lidocaine to skin. 18G finder needle at 45° angle into IJ under US. Aspirate dark non-pulsatile blood. Thread guidewire through needle (should pass easily -if resistance, reposition). Remove needle over wire.
Dilate
Nick skin with scalpel. Thread dilator over wire with twisting motion -only insert 2–3 cm (just enough to dilate the tract). Remove dilator.
Catheter
Thread catheter over wire. Right IJ: 15–17 cm depth (tip at cavoatrial junction). Left IJ: 17–19 cm. ALWAYS confirm wire out the back of the catheter before securing.
Confirm
Aspirate and flush all ports. Suture + sterile dressing. Post-procedure CXR to confirm tip position (at carina or slightly above) and rule out PTX.
NEVER lose control of the wire. Always have a hand on it. If the wire won't thread → reposition the needle, don't force. If you aspirate bright red pulsatile blood → you're in the carotid → remove needle, hold pressure × 10 min.
🩺 Arterial Line
Sites & Technique
Site
Notes
Radial (1st choice)
Most common. Superficial, easy to access. Modified Allen test before (check ulnar collateral -though evidence for utility is weak). Wrist extension 30° on roll. US-guided preferred. 20G catheter-over-needle. Angle 15–30°.
Femoral (2nd)
Larger artery, easier to access in shock (radial may be pulseless). Below inguinal ligament, lateral to femoral vein (NAVEL: Nerve-Artery-Vein-Empty-Lymphatics).
Brachial / dorsalis pedis
Alternative sites. Brachial is an end-artery → higher ischemia risk.
Indications
Continuous BP monitoring (vasopressor titration, hemodynamic instability)
Supine or slight lateral decubitus (fluid pools to dependent side). Empty bladder first (or confirm with US).
Landmark
Left lower quadrant, 2 fingerbreadths medial and 2 cephalad to ASIS. Avoids the inferior epigastric artery (runs in the rectus sheath). US-guided preferred -mark the pocket with the deepest fluid and no underlying bowel.
Access
Sterile prep. Lidocaine track down to peritoneum (you'll feel a "pop"). 18G needle or 15–18G catheter-over-needle (preferred for large volume). Z-track technique: pull skin 2 cm caudally before inserting → prevents persistent leak after removal.
Drain
Diagnostic: 60–100 mL (send cell count, albumin, protein, culture in blood bottles). Therapeutic: drain to dryness (up to 8–10 L). If > 5 L → give albumin 6–8 g per liter removed.
INR and platelets are NOT contraindications. Bleeding rate < 1% even with coagulopathy. Do NOT transfuse before paracentesis in cirrhotic patients.
🩺 Thoracentesis
Technique
Position
Sitting upright, leaning forward over bedside table (arms resting on pillow). Maximizes dependent pooling and intercostal space width.
Landmark
US-guided mandatory (reduces PTX from ~10% to < 1%). Mark site with largest fluid pocket, ≥ 10 mm depth, no lung sliding. Insert 1–2 intercostal spaces below the fluid meniscus. Go OVER the top of the rib (neurovascular bundle runs under each rib -intercostal artery, vein, nerve).
Access
Sterile prep + drape. Lidocaine to skin → deeper → walk over the top of the rib → into the pleural space (you'll aspirate fluid). Insert 16–18G catheter-over-needle or thoracentesis kit (safe-T-centesis). Attach tubing to vacuum bottles.
Drain
Diagnostic: 50–60 mL. Therapeutic: up to 1.5 L maximum per session (risk of re-expansion pulmonary edema if > 1.5 L). Stop if: cough, chest tightness, or pleuritic pain (lung against chest wall).
Post-procedure CXR is NOT routinely needed if US-guided and uncomplicated. Only get CXR if: air aspirated, symptoms develop, or multiple needle passes.
🩺 Lumbar Puncture
Technique
Position
Lateral decubitus (fetal position -knees to chest, chin tucked) or seated upright leaning forward. Lateral decubitus is required for accurate opening pressure measurement.
Landmark
L3–L4 or L4–L5 interspace. Find the iliac crests (a line between them = Tuffier's line = approximately L4 vertebral body). Palpate the spinous processes. Spinal cord ends at L1–L2 in adults -always go below L2.
Access
Sterile prep + drape. Lidocaine skin to deeper tissues. 22G spinal needle with stylet, bevel up (parallel to the longitudinal dural fibers). Aim slightly cephalad (toward the umbilicus). Advance slowly -feel a "pop" through the ligamentum flavum and dura. Remove stylet to check for CSF flow.
Collect
Opening pressure first (attach manometer -patient must be in lateral decubitus with legs slightly extended for accurate reading). Normal: 6–20 cmH₂O. Collect 4 tubes (~1–2 mL each): Tube 1 = cell count, Tube 2 = glucose + protein, Tube 3 = Gram stain + culture, Tube 4 = cell count (to distinguish traumatic tap from SAH -RBC should decrease from tube 1 to 4 in traumatic tap).
When to Get CT Before LP
CT first if: immunocompromised, CNS disease history, new seizure, papilledema, focal neuro deficit, altered consciousness
None of these → LP without CT is safe. Do NOT delay antibiotics for imaging if meningitis suspected.
Post-LP headache (~10%): positional (worse upright, better supine). Treat with caffeine, IV fluids, analgesics. Refractory → epidural blood patch. Use atraumatic needles (Sprotte/Whitacre) when available -50% lower headache rate vs cutting needles.
Quick Reference
ECG Interpretation
A systematic approach to every ECG. Rate → rhythm → axis → intervals → ST-T changes. Learn the patterns that can kill -STEMI, hyperkalemia, PE, WPW, and long QT.
📐 Systematic ECG Reading
Step 1 -Rate
Regular rhythm: 300 ÷ (number of large boxes between R-R). Or: 300, 150, 100, 75, 60, 50 for 1, 2, 3, 4, 5, 6 large boxes.
Irregular rhythm: count QRS complexes in a 6-second strip (30 large boxes) × 10
Avoid AV nodal blockers (adenosine, CCB, digoxin, BB) in Afib + WPW → can cause VFib. Use procainamide or cardioversion.
Brugada
Type 1: coved ST elevation > 2 mm + T wave inversion in V1–V3 (pseudo-RBBB).
Risk of sudden cardiac death. Unmasked by fever, Na-channel blockers. Treatment: ICD.
TCA overdose
QRS > 100 ms + R wave in aVR > 3 mm + right axis + sinus tachycardia
Sodium bicarbonate. QRS > 160 = VT risk. See Toxicology.
Complete heart block
Regular P waves marching through at one rate, QRS at a slower rate. No PR relationship. AV dissociation.
Transcutaneous pacing → transvenous pacing. Atropine may help if junctional escape (narrow QRS). Atropine does NOT work if infranodal block (wide QRS).
Pericarditis
Diffuse ST elevation (concave-up, "smiley face") + PR depression (best in II) + Spodick's sign (downsloping TP segment)
Distinguish from STEMI: diffuse (not territorial), PR depression, no reciprocal changes, concave-up morphology.
Bradycardia, heart block (RCA supplies AV node). Check right-sided leads (V4R) for RV infarct.
RV infarct
V4R ≥ 1 mm STE
-
Proximal RCA
Preload-dependent → fluids, NO nitrates/diuretics/morphine.
Posterior
ST depression V1–V3 (mirror image) + tall R wave V1
-
PDA or LCx
Often missed. Get posterior leads (V7–V9): STE ≥ 0.5 mm confirms.
New LBBB is no longer an automatic STEMI-equivalent. Use Sgarbossa criteria: (1) concordant STE ≥ 1 mm = 5 pts, (2) ST depression ≥ 1 mm in V1–V3 = 3 pts, (3) discordant STE ≥ 5 mm = 2 pts (modified: use proportional ratio > 0.25 of preceding S wave). Score ≥ 3 → STEMI despite LBBB.
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EMERGENTQuick Reference
Code Blue & Rapid Response
Your pocket card for running or assisting in a code. ACLS algorithms, drug doses, H's & T's, and the rapid response assessment framework. Launch Code Clock for real-time code documentation.
⏱️ Code Clock App
Real-time code documentation -track interventions, drug times, rhythm checks, and generate a code summary.
Confirm ETT placement (ETCO₂). Auscultate both lungs. If no breath sounds unilateral → mainstem intubation or PTX. Suction. Increase FiO₂ to 100%.
Hydrogen ion (acidosis)
Known DKA, renal failure, severe sepsis, toxic ingestion (methanol, ethylene glycol, ASA). Pre-arrest ABG with pH < 7.1.
Sodium bicarbonate 1 mEq/kg IV push. Ventilate aggressively (blow off CO₂). Treat underlying cause (insulin for DKA, dialysis for renal failure, fomepizole for toxic alcohols).
Hyper/Hypokalemia
Renal failure (hyperK), dialysis patient who missed session, recent K⁺ lab, ECG changes (peaked T waves, wide QRS). HypoK: diuretic use, GI losses, prolonged QT.
HyperK: Calcium chloride 1–2g IV push (stabilize membrane) → insulin 10 units + D50 → bicarb → albuterol. HypoK: KCl 40 mEq IV + MgSO₄ 2g IV.
Hypothermia
Found down outdoors, drowning, exposure, elderly. Core temp < 30°C. "Not dead until warm and dead."
Active rewarming: warm IVF (40°C), warm humidified O₂, forced-air warming blankets. If < 30°C: defib may not work until rewarmed → limit to 1 shock attempt, hold meds until temp > 30°C. Continue CPR. Consider ECMO rewarming if available.
Hypoglycemia
Diabetic on insulin/sulfonylureas, altered mental status pre-arrest, missed meals, liver failure, adrenal crisis.
D50 (dextrose 50%) 1 amp (25g) IV push. Recheck in 15 min. If no IV access: glucagon 1 mg IM.
T's
Tension pneumothorax
Absent breath sounds unilaterally, JVD, tracheal deviation (late sign), recent central line or thoracentesis, trauma, patient on positive pressure ventilation.
Needle decompression: 14–16G needle, 2nd intercostal space midclavicular line (or 5th ICS anterior axillary). Do NOT wait for CXR. Follow with chest tube (28–32 Fr).
Pericardiocentesis: subxiphoid approach, US-guided. Remove even 20–30 mL → dramatic improvement. In post-surgical: emergent sternotomy (re-open).
Toxins
Pill bottles at scene, history of depression/suicidal ideation, drug paraphernalia. Wide QRS (TCAs, Na-channel blockers). Opioid presentation (pinpoint pupils). Bradycardia (beta-blocker, CCB, digoxin). Seizure history (local anesthetic toxicity).
Specific antidotes: Naloxone (opioid), sodium bicarb (TCA -QRS > 100), intralipid 20% (local anesthetic toxicity, lipophilic drug OD), glucagon (beta-blocker), calcium + high-dose insulin (CCB), DigiFab (digoxin). See Toxicology.
Thrombosis -coronary (MI)
Pre-arrest chest pain, STEMI on last ECG, known CAD, cardiac risk factors. PEA with organized narrow-complex rhythm on monitor.
Consider emergent PCI (cath lab activation during CPR -some centers do this). If no PCI available: fibrinolytics (tPA 50 mg IV during CPR) -consider if high suspicion and no other cause found. Continue CPR for 60–90 min after lytics.
Thrombosis -pulmonary (Category E PE)
Pre-arrest dyspnea + pleuritic pain + tachycardia, recent surgery/immobilization/cancer, known DVT, RV strain on prior echo, dilated RV on bedside echo during CPR.
Systemic thrombolytics: tPA 50 mg IV bolus (can give during CPR). Continue CPR for 60–90 min after lytics to allow time to work. If available: consider surgical embolectomy or catheter-directed therapy. Bedside echo during CPR showing RV dilation supports PE diagnosis.
💊 Code Drug Doses
Drug
Dose
Indication
Epinephrine (Adrenalin)
1 mg IV q3–5 min
All cardiac arrest rhythms. First-line vasopressor.
Amiodarone (Cordarone)
300 mg IV push (1st dose), 150 mg (2nd dose)
Refractory VFib/pVT after 3+ shocks.
Lidocaine
1–1.5 mg/kg IV, then 0.5–0.75 mg/kg
Alternative to amiodarone for VFib/pVT.
Atropine
1 mg IV q3–5 min (max 3 mg)
Symptomatic bradycardia (NOT for asystole or PEA).
Adenosine (Adenocard)
6 mg rapid IV push → if no effect → 12 mg (two doses only)
Stable SVT. Must use rapid push + flush at proximal IV site.
Calcium chloride
1–2 g IV (10–20 mL of 10%)
Hyperkalemia with ECG changes, calcium channel blocker OD, hypocalcemia.
Calcium gluconate
3 g IV (30 mL of 10%)
Same indications. 3× less elemental calcium than CaCl₂. Safer peripherally.
Sodium bicarbonate
1 mEq/kg IV
Severe metabolic acidosis, TCA overdose, hyperkalemia (adjunct).
Magnesium
2 g IV over 15 min
Torsades de pointes. Also hypomagnesemia-related arrhythmias.
Vasopressin (Pitressin)
40 units IV × 1
Can replace first or second epi dose in cardiac arrest (AHA 2020 removed specific recommendation but still acceptable).
🏥 Rapid Response Assessment
When You Get the Call -ABCDE
A -Airway
Speaking? Stridor? Secretions? Can they protect their airway? If not → jaw thrust, suction, consider intubation. Call anesthesia early if airway is threatened.
B -Breathing
RR, SpO₂, work of breathing, auscultate. Wheezing → bronchodilator. Crackles → fluid overload vs pneumonia. Absent breath sounds → PTX? Stridor → upper airway obstruction → call ENT/anesthesia. Apply O₂ while assessing.
C -Circulation
HR, BP, rhythm, mental status, cap refill, urine output. If hypotensive → IVF bolus (unless cardiogenic). If no pulse → call code, start CPR. Get 12-lead ECG. Access: 2 large-bore IVs.
The 6 calls you'll get at 3 AM and the 60-second decision tree for each. Assess, intervene, decide if you need to call your senior.
🌡️ Fever (T ≥ 38.3°C / 101°F)
Assess
Vitals (HR, BP, SpO₂). Is the patient septic? (Tachycardic, hypotensive, altered?) Look at the patient -line sites, surgical wounds, skin, lungs, abdomen, Foley.
Workup
Blood cultures × 2 (before abx). UA + urine culture. CXR. CBC, BMP, lactate. C. diff stool if diarrhea. Line cultures if central line > 48h. Wound culture if surgical site erythema.
Intervene
Acetaminophen 1g PO/IV. If septic → IVF bolus + start empiric antibiotics per source. If neutropenic → cefepime 2g IV within 60 min (oncologic emergency).
Call senior if
Sepsis (HR > 110, SBP < 90, lactate > 2, altered). Neutropenic fever (ANC < 500). New fever on immunosuppression. Unclear source with clinical deterioration.
Common pitfalls: Post-op day 1–2 fever is often atelectasis (encourage incentive spirometry) -but still work it up. Drug fever (eosinophilia, timing with new med). DVT (check legs). C. diff (new diarrhea + recent abx).
📉 Hypotension (SBP < 90 or MAP < 65)
Assess
Go see the patient immediately. Vitals + mental status. Check lines/drains for blood. Recent meds (antihypertensives, opioids, sedatives). Abdomen (GI bleed?). JVD (PE, tamponade, tension PTX)?
Intervene
IVF bolus 500 mL–1L NS or LR. Passive leg raise to assess fluid responsiveness. Hold antihypertensives. If on pressors → uptitrate and notify ICU. If bleeding → type and screen, activate MTP if massive.
Apply O₂ first, assess second. Check probe placement (cold fingers, nail polish give false readings). Confirm with ABG if uncertain. Look at patient: work of breathing, tracheal position, breath sounds, JVD.
Intervene
Nasal cannula 2–6 L → face mask 10–15 L → non-rebreather → high-flow nasal cannula → BiPAP → intubation. If wheezing → albuterol nebulizer. If crackles + JVD → furosemide IV (flash pulm edema). If absent breath sounds unilateral → PTX? (needle decompress if tension).
Workup
CXR (stat portable), ABG, 12-lead ECG. Consider: CTPA if PE suspected (tachycardia + pleuritic pain + risk factors). BNP if heart failure. Troponin if ACS.
Call senior if
Not improving with supplemental O₂. Need for BiPAP or intubation. Concern for PE, PTX, or flash pulm edema. New infiltrate on CXR in the right clinical context.
Top 5 overnight causes: mucus plug (suction + turn), flash pulmonary edema (Lasix), PE, aspiration, pneumothorax (post-procedure or on vent). Also: opioid-induced hypoventilation → check RR, give naloxone if < 8.
🧠 Altered Mental Status
Assess
Stat fingerstick glucose (hypoglycemia is the fastest fixable cause). Vitals. Pupils. GCS. Focal neuro exam (asymmetry → stroke alert). Review med list (opioids, benzos, anticholinergics).
Intervene
Glucose < 70 → D50 1 amp IV. Suspected opioid OD (pinpoint pupils, RR < 8) → naloxone 0.4 mg IV. Benzodiazepine OD → supportive (flumazenil rarely indicated). Seizure → lorazepam 4 mg IV.
Workup
BMP (Na⁺, Ca²⁺, glucose), CBC, ammonia (if liver disease), UA (UTI in elderly?), ABG, lactate. CT head if focal deficit, fall, anticoagulated, or not improving. Consider LP if meningitis suspected (fever + nuchal rigidity).
Call senior if
Focal neuro deficit (stroke alert). Seizure. Meningeal signs. Not correcting with glucose/naloxone. GCS ≤ 8 (airway at risk).
Most common overnight AMS cause: delirium from medications. Review med list first -Benadryl, benzos, opioids, anticholinergics, steroids. Reorient, minimize stimulation, avoid restraints. Haldol 0.5–1 mg IV only if danger to self/others.
💔 Chest Pain
Assess
12-lead ECG within 10 min. Vitals. Character of pain (substernal pressure vs pleuritic vs positional vs reproducible). Cardiac history. Risk factors.
Intervene
ASA 325 mg chew (if ACS suspected and not already on). NTG 0.4 mg SL q5 min × 3 (hold if SBP < 90 or suspected RV infarct). Morphine only if refractory (not routine). O₂ if SpO₂ < 94%.
Workup
ECG (compare to prior). Troponin (serial 0 and 3h if hs-troponin). CXR. BMP. If ECG shows STEMI → activate cath lab immediately. If PE suspected → D-dimer or CTPA based on Wells score.
Call senior if
STEMI or new ST changes. Hemodynamic instability. Concern for dissection (tearing pain + BP differential). Positive troponin. Chest pain not resolving with NTG.
💧 Low Urine Output (< 0.5 mL/kg/hr × 6h)
Assess
Is the Foley kinked, clogged, or draining? Flush 30 mL NS. If no Foley → bladder scan (> 300 mL = retention → straight cath). Check vitals, volume status (dry vs overloaded), recent meds (NSAIDs, ACEi, diuretics).
Intervene
If hypovolemic → IVF 500 mL NS bolus. If retention → straight cath or Foley. Stop nephrotoxins (NSAIDs, aminoglycosides, contrast). Hold ACEi/ARB if Cr rising. If overloaded (JVD, crackles, edema) → do NOT give more fluid -consider diuresis.
Workup
BMP (Cr trend -compare to baseline), UA with sediment, bladder scan. FENa or FEUrea to differentiate pre-renal vs intrinsic (see Calculators). Consider renal US if obstruction suspected.
Potassium, magnesium, phosphate and calcium repletion plus the sodium correction limits, all in one place. You'll order these 10 times a day: how much, how fast, PO vs IV, and when to recheck.
⚡ Replacement Protocols
Electrolyte
Level
Replacement
Expected Rise
Recheck
Pearls
Potassium (Goal: 4.0–5.0) (ICU goal: 4.0–4.5)
3.5–3.9
KCl 40 mEq PO × 1
~0.2–0.4 mEq/L total classic rule is 0.1 per 10 mEq, but the real-world inpatient median is ~0.05
Next AM BMP
Always replete Mg first -hypoMg causes renal K⁺ wasting via the ROMK channel. Mg²⁺ normally inhibits ROMK in the collecting duct. When Mg²⁺ is low → ROMK becomes uninhibited → K⁺ pours into the urine → refractory hypokalemia no matter how much K⁺ you give. Fix the Mg²⁺ first, or the K⁺ won't stay. Max IV rate: 10 mEq/hr peripheral, 20 mEq/hr central. PO preferred if tolerating. Recheck K⁺ 2–4h after IV repletion.
3.0–3.4
KCl 40 mEq PO × 2 doses (1h apart) or KCl 20 mEq IV × 2
~0.4–0.8 mEq/L
2–4h post-IV
< 3.0
KCl 40 mEq IV × 2–3 (with continuous telemetry). PO supplement simultaneously.
Variable -recheck frequently
Q2h until > 3.0
Magnesium (Goal: ≥ 2.0) (ICU goal: ≥ 2.0)
1.5–1.9
MgOxide 400 mg PO BID or MgSO₄ 2g IV × 1
~0.1–0.2 per 1g IV
Next AM
Diarrhea is the dose-limiting PO side effect. IV preferred in critically ill. 1g IV MgSO₄ ≈ 8 mEq Mg. Renal excretion -use caution in CKD. For torsades → 2g IV push.
Why Mg matters for K⁺ (ROMK channel): Mg²⁺ normally blocks the ROMK channel in the collecting duct, preventing K⁺ secretion. Low Mg²⁺ → ROMK uninhibited → kidney wastes K⁺ → refractory hypokalemia. Also: low Mg²⁺ causes PTH resistance → refractory hypocalcemia. Always check Mg²⁺ when K⁺ or Ca²⁺ won't correct.
< 1.5
MgSO₄ 4g IV over 4h
~0.3–0.5
2–4h post
Phosphorus (Goal: 2.5–4.5)
1.5–2.4
NeutraPhos 2 packets PO (32 mmol) or Na/K-Phos 15 mmol IV over 2h
~0.5–1.0 mg/dL
Next AM
IV repletion in CKD → risk of hypocalcemia (CaPO₄ precipitation). Check Ca²⁺ concurrently. Oral preferred unless severe or NPO. K-Phos contains potassium -check K⁺ first.
< 1.5
Na/K-Phos 30 mmol IV over 4–6h
~1.0–1.5 mg/dL
2–4h post
Calcium (Ionized goal: 1.1–1.3)
Mild (iCa 0.9–1.1)
CaCO₃ 1250 mg PO TID (with meals) + vitamin D
Gradual
Next AM
Always check ionized Ca (not total -albumin confounds). Correct Mg first (hypoMg causes PTH resistance). IV CaCl₂ = 3× more elemental Ca than Ca gluconate but vesicant (central line only). Avoid IV Ca if hyperphosphatemic (CaPO₄ precipitation → calciphylaxis).
Severe (iCa < 0.9, symptomatic)
Ca gluconate 2g IV over 20 min (peripheral OK) or CaCl₂ 1g IV (central only)
Transient
Q2h + telemetry
📐 The dosing arithmetic, and why "Expected Rise" is a range
Classic teaching is that every 10 mEq of KCl raises serum K⁺ by 0.1 mEq/L, so 40 mEq buys about 0.4. Treat that as a best case, not an average. It reflects acute IV dosing: in a medical ICU series of 495 infusion sets, 20 mEq of IV KCl raised K⁺ by a mean of 0.25 mEq/L measured right after the infusion Kruse & Carlson, 1990.
Across a hospital day it under-delivers badly. In 800 supplemented inpatients (median 40 mEq/day, 81% oral) the median rise was only 0.05 mEq/L per 10 mEq, improving to 0.07 in patients on no K⁺-affecting drugs and falling to 0.03 on a loop diureticAJHP, 2024. In an ICU cohort, only 35% of replacement episodes hit the rule-predicted target. Expect roughly half the textbook rise in anyone still on a diuretic, and recheck the level rather than trusting the arithmetic.
Why one dose is rarely enough: only about 2% of body potassium is extracellular, so the serum value is the tip of the iceberg. Each 1 mEq/L below normal represents a 200–400 mEq total-body deficit. A K⁺ of 2.5 is a whole-body hole of 400 mEq or more, which is why the level drifts back down a few hours after you stop replacing.
🔗 The Mg²⁺ → K⁺ → Ca²⁺ Connection (ROMK Channel)
Low Mg²⁺ causes THREE problems: 1. Refractory hypokalemia -Mg²⁺ normally blocks the ROMK channel (Renal Outer Medullary K⁺ channel) in the collecting duct. Without Mg²⁺ → ROMK is wide open → kidney wastes K⁺ into urine → no amount of K⁺ repletion will stick until Mg²⁺ is corrected. 2. Refractory hypocalcemia -Mg²⁺ is required for PTH secretion and end-organ response. Low Mg²⁺ → PTH resistance → Ca²⁺ won't correct. 3. Cardiac arrhythmias -Mg²⁺ stabilizes cardiac membranes. Low Mg²⁺ → prolonged QT → Torsades de Pointes, refractory Afib/RVR, digoxin toxicity.
Clinical rule: When K⁺ or Ca²⁺ won't correct despite adequate repletion → check and replete Mg²⁺ first.
🛡️ Rates, Routes & Safety
IV rate and route limits
Electrolyte
Peripheral
Central
Why the cap exists
Potassium
10 mEq/hr concentration ≤ 40 mEq/L
20 mEq/hr
Faster or more concentrated burns and causes phlebitis, which is the usual reason a peripheral infusion gets abandoned half finished. Rates up to 40 mEq/hr are reserved for arrest-level hypokalemia with ECG changes, central access, and continuous monitoring. Telemetry once K⁺ < 3.0.
Magnesium
2 g over 1–2h; 4 g over 4h if Mg < 1.0
A fast push causes flushing, warmth, and hypotension. Halve the dose in renal impairment, since Mg is renally cleared. 1 g MgSO₄ ≈ 8 mEq. A severely depleted patient may need 8–12 g over 24h.
Phosphate
Max 7 mmol/hr
Faster infusion risks hypocalcemia from CaPO₄ precipitation and AKI. Check Ca²⁺ alongside, and reduce the dose in renal failure.
Calcium
Ca gluconate is safe peripherally
CaCl₂ central line only
CaCl₂ delivers 3× the elemental calcium but is a vesicant that causes tissue necrosis if it extravasates. Reserve it for arrest or profound instability where the extra calcium per mL matters.
⚠️ Mix IV KCl in saline, not dextrose. Dextrose triggers endogenous insulin, which drives K⁺ into cells and can drop the serum level further before it rises. The same logic explains why you never start insulin in DKA until K⁺ is ≥ 3.3–3.5.
🧪 Choosing the phosphate salt: use K-Phos when K⁺ is also low, since it repletes both, and Na-Phos when K⁺ is normal or high. K-Phos carries roughly 1.1 mEq of K⁺ per mmol of phosphate, so ordering it in a hyperkalemic patient is an easy and entirely avoidable error.
🚫 Avoid IV calcium in a hyperphosphatemic patient unless the hypocalcemia is symptomatic. CaPO₄ precipitates in tissue and drives calciphylaxis. In tumor lysis, correct the phosphate first and treat only symptomatic hypocalcemia.
When to recheck
Situation
Recheck
Why
Oral repletion, stable patient
2–4h, or next AM BMP
Drawing it earlier reads the dose, not the patient.
IV repletion
1–2h after the infusion ends
A level drawn mid-infusion reads falsely high, especially if sampled from the infusing arm.
K⁺ < 3.0, or any arrhythmia
q1–2h until > 3.0
Reassess between doses rather than chasing a target with one large bolus. The infusion rate that is safe at 2.2 is not safe at 3.8.
Refractory after two adequate doses
Send Mg²⁺, and Ca²⁺ if that is also low
Renal K⁺ wasting through an unblocked ROMK channel will defeat any amount of repletion until the magnesium is corrected.
🔴 Sodium & Correction Limits
Sodium is a correction problem, not a repletion problem. What you are titrating is the rate of change, not a dose, and the harm comes from moving it too fast in either direction. The full diagnostic workups live in Hyponatremia and Hypernatremia; the limits below are what you need at the bedside.
≤ 8
mEq/L rise in 24h (max safe correction rate)
≤ 10–12
mEq/L rise in 48h (be stricter if chronic or high-risk)
ODS
Osmotic demyelination if corrected too fast
Problem
What to give
The limit, and why
Hyponatremia Na⁺ < 135
NS if hypovolemic, fluid restriction if euvolemic (SIADH), diuresis if hypervolemic. 3% hypertonic saline 100 mL bolus for seizure or coma, repeat up to 3 times, recheck Na⁺ in 2h.
≤ 8 mEq/L in 24h. The brain has already shed osmolytes to survive the low tonicity; raising the sodium faster than it can replace them demyelinates the pons, producing an irreversible locked-in syndrome 2 to 6 days later. Highest risk: chronic hyponatremia, alcohol use, malnutrition, hypokalemia, liver disease.
Overcorrection already up > 8 in 24h
D5W 3–6 mL/kg/hr plus DDAVP 2 mcg IV q8h to re-lower the sodium.
Act immediately. ODS is preventable at this stage and irreversible once established, so relowering to the safe trajectory is worth doing even if it feels like undoing your own work.
Hypernatremia Na⁺ > 145
Enteral water is safest if the gut works, otherwise D5W. Restore perfusion with isotonic fluid first if shocked.
≤ 10 mEq/L in 24h if chronic, since the adapted brain swells when water rushes back in, causing cerebral edema and seizures. Free water deficit = TBW × (Na⁺/140 − 1), TBW = 0.6 × wt in men and 0.5 × wt in women. Add insensible losses (~30–50 mL/hr) and ongoing urine output, or the sodium will plateau.
⚠️ Potassium counts toward the sodium correction rate. Every mEq of K⁺ you give is osmotically active: K⁺ enters cells and Na⁺ comes out, so aggressive potassium repletion raises the serum sodium roughly as much as giving the same amount of sodium would. If you are correcting hypokalemia and hyponatremia together, the sodium will rise faster than your formula predicts. Count the potassium in your 24h budget and recheck early.
RoundsRx Infographic Series · #11 · Renal & Metabolic · PDF 151 KB
📄 Also in the series:Hypokalemia (#151) goes deeper on potassium alone: severity and ECG findings, the replacement arithmetic and why it over-promises, the magnesium rule, and the urine K⁺/creatinine workup. For the hyperkalemia emergency algorithm see Hyperkalemia.
CoreQuick Reference
Pain Management & Conversions
WHO pain ladder, PCA dosing, multimodal analgesia, equianalgesic opioid conversions, and steroid equivalency. The complete analgesic guide.
📶 WHO Pain Ladder & Analgesic Guide
WHO Analgesic Ladder (Modified)
Start at the step that matches the patient's pain severity. You do NOT have to climb from Step 1 → 2 → 3 sequentially. A patient with severe post-op pain can start at Step 3 immediately. Add adjuvants at EVERY step.
Step 1 -Mild Pain (1–3/10)
Non-opioid analgesics:
• Acetaminophen (Tylenol) 650–1000 mg PO q6h (max 3g/day if liver disease, 4g if healthy)
• Ibuprofen (Advil) 400–600 mg PO q6h with food
• Ketorolac (Toradol) 15–30 mg IV q6h (max 5 days -renal/GI risk)
• Celecoxib (Celebrex) 200 mg PO BID (lower GI bleed risk)
⚠️ NSAIDs: avoid in CKD (GFR < 30), active GI bleed, HF, post-CABG, concurrent anticoagulation, platelets < 50K
Step 2 -Moderate Pain (4–6/10)
Weak opioids ± non-opioids:
• Tramadol (Ultram) 50–100 mg PO q6h (max 400 mg/day)
• Hydrocodone/APAP (Norco) 5/325 -1-2 tabs q4-6h
• Oxycodone IR (OxyContin) 5 mg PO q4-6h PRN
• Continue scheduled acetaminophen + NSAIDs if safe
⚠️ Tramadol: seizure risk, serotonin syndrome with SSRIs/SNRIs, avoid in epilepsy
Step 3 -Severe Pain (7–10/10)
Strong opioids ± non-opioids:
• Morphine (MS Contin) 2–4 mg IV q3-4h PRN
• Hydromorphone (Dilaudid) 0.5–1 mg IV q3-4h PRN
• Fentanyl (Sublimaze) 25–50 mcg IV q1-2h (short duration)
• Oxycodone 5–10 mg PO q4h
• Continue non-opioid adjuncts (multimodal)
⚠️ Always start bowel regimen with opioids (PEG 3350 + senna). No ceiling for opioid dose in cancer/palliative pain.
Same as gabapentin, higher affinity, more predictable (linear) absorption. ~6× more potent than gabapentin (300 mg gabapentin ≈ 50 mg pregabalin), so dose numbers are smaller.
75 mg PO BID → max 300 mg BID
Neuropathic pain, fibromyalgia
⚠️ Same as gabapentin. Schedule V controlled substance (abuse potential).
Duloxetine (Cymbalta)
SNRI -inhibits serotonin + norepinephrine reuptake in descending pain pathways
⚠️ Sedation (all), hepatotoxicity (tizanidine), anticholinergic (cyclobenzaprine). Baclofen withdrawal can cause seizures.
PCA (Patient-Controlled Analgesia) Dosing
PCA is for patients who can self-dose -must be alert, understand the button, and have no cognitive impairment. Family members should NEVER press the PCA button (risk of oversedation/respiratory arrest).
Opioid
Demand Dose
Lockout
Basal Rate (if needed)
1-hour Limit
Notes
Morphine PCA
1–2 mg
6–10 min
0–1 mg/hr (avoid in opioid-naive)
10 mg
Standard first-line PCA. Avoid in renal failure (M6G accumulation).
Hydromorphone PCA
0.2–0.4 mg
6–10 min
0–0.2 mg/hr
2 mg
Preferred in renal impairment. ~5–7× more potent than morphine IV.
Fentanyl PCA
10–25 mcg
6–10 min
0–25 mcg/hr
150 mcg
Short acting. Good for procedure-related pain. Lipophilic -accumulates with prolonged use.
⚠️ Basal rate + PCA in opioid-naive patients = dangerous. A continuous basal rate removes the safety net of the PCA system (patient stops pressing button when sedated). Use demand-only dosing for opioid-naive patients. Basal rate only for opioid-tolerant patients with established requirements.
IV → PO Opioid Conversion -When to Switch
Switch IV → PO when: patient tolerating PO intake, pain controlled ≥ 24h on stable IV dose, no nausea/vomiting
How: Calculate total 24h IV morphine equivalents → convert to PO using equianalgesic table → reduce by 25% for cross-tolerance → split into scheduled + PRN
Example: Patient on morphine PCA using 30 mg IV/24h → PO equivalent = 30 × 3 = 90 mg PO morphine/day → reduce 25% = ~68 mg → split: oxycodone ER 30 mg PO BID (60 mg/day) + oxycodone IR 5–10 mg q4h PRN for breakthrough
PRN breakthrough dose: 10–15% of total daily dose given q3-4h PRN
Multimodal Analgesia -The Modern Approach
Multimodal = combine drugs from different classes to target different pain pathways. This reduces opioid requirements by 30–50%, lowers side effects, and improves pain control. Every patient should get scheduled acetaminophen + NSAID (if safe) BEFORE reaching for opioids.
Gabapentin/pregabalin + duloxetine + lidocaine patch. Opioids are second-line (less effective for neuropathic pain).
Cancer / bone mets
Scheduled long-acting opioid + APAP + dexamethasone 4–8 mg + radiation therapy referral. Bisphosphonates for widespread bone mets.
Sickle cell VOC
IV morphine/hydromorphone PCA + scheduled APAP + ketorolac (≤ 5 days) + low-dose ketamine if refractory. NSAIDs safe short-term if GFR ok.
Chronic non-cancer
Maximize non-opioid: APAP, NSAIDs, duloxetine, gabapentin, PT/CBT. Opioids are last resort -risks of dependence, hyperalgesia.
Palliative / end-of-life
Scheduled opioid (no ceiling) + PRN breakthrough + adjuvants. Titrate to comfort. Address total pain (physical, emotional, spiritual).
Tiered PRN Pain Order Set -What to Write on Admission
Write pain orders in 3 tiers so the nurse can choose based on the patient's assessed pain level -without paging you for every dose. The nurse uses NRS (0–10) for alert patients or CPOT (0–8) for intubated/non-verbal patients to select the right tier.
Alert Patients -Numeric Rating Scale (NRS 0–10)
Pain Level
NRS Score
Medication
Dose
Route
Frequency
Mild
1–3
Acetaminophen (Tylenol)
650–1000 mg
PO
q6h PRN
Moderate
4–6
Oxycodone IR (OxyContin)
5 mg
PO
q4h PRN
Moderate
4–6
Alternative:Tramadol (Ultram)
50 mg
PO
q6h PRN
Severe
7–10
Hydromorphone (Dilaudid)
0.5–1 mg
IV
q3h PRN
Severe
7–10
Alternative:Morphine (MS Contin)
2–4 mg
IV
q3-4h PRN
⚠️ Adjust for special populations:
• Elderly / CKD / hepatic: Start at lower end of each tier (oxycodone 2.5 mg, hydromorphone 0.25 mg)
• Opioid-tolerant: May need higher doses at each tier
• Post-surgical: Add scheduled APAP 1g q6h + ketorolac 15 mg IV q6h (multimodal reduces opioid need by 30–50%)
Intubated / Non-Verbal Patients -CPOT Score (0–8)
Domain
0 Points
1 Point
2 Points
Facial expression
Relaxed, neutral
Tense (brow furrowed, orbit tightened)
Grimacing (teeth clenching, deep furrows)
Body movements
Absent, normal position
Protection (slow, cautious, touching pain site)
Restlessness (pulling at tubes, attempting to sit up, thrashing)
Compliance with ventilator (intubated) orVocalization (extubated)
Muscle tension (passive flexion/extension of upper extremity)
Relaxed, no resistance
Resistance to passive movements
Strong resistance, unable to complete movement
Pain Level
CPOT Score
Medication
Dose
Route
Frequency
Minimal
0–2
Acetaminophen (Tylenol)
1000 mg
IV
q6h PRN
Moderate
3–4
Fentanyl (Sublimaze)
25 mcg
IV
q2h PRN
Significant
5–8
Fentanyl (Sublimaze)
50–100 mcg
IV
q1-2h PRN
Significant
5–8
Alternative:Hydromorphone (Dilaudid)
0.5 mg
IV
q3h PRN
⚠️ CPOT ≥ 3 = significant pain -treat it. Intubated patients cannot tell you they hurt. Studies show ICU patients experience moderate-to-severe pain during routine care (turning, suctioning, wound care). Undertreated pain increases delirium, prolongs ventilation, and causes PTSD.
⚠️ Always reassess within 30 minutes of giving PRN pain medication. If CPOT or NRS unchanged → escalate to next tier or consider continuous infusion. Document pre- and post-intervention pain scores.
💊 Opioid Equianalgesic Table
When converting between opioids, reduce the calculated equianalgesic dose by 25–50% to account for incomplete cross-tolerance. Conversion ratios are approximate -always titrate to effect.
Opioid
IV/IM Dose
PO Dose
IV:PO Ratio
Duration
Notes
Morphine (MS Contin)
10 mg
30 mg
1:3
3–4h
Reference standard. Active metabolite (M6G) accumulates in renal failure → ↑ sedation/respiratory depression.
Hydromorphone (Dilaudid)
1.5 mg
7.5 mg
1:5
3–4h
~7× more potent than morphine IV. Preferred in renal failure (no active metabolite). Most commonly used IV opioid on wards.
Oxycodone (OxyContin)
N/A (PO only)
20 mg
PO only
3–4h
~1.5× morphine PO. Available as IR and ER (OxyContin).
Hydrocodone
N/A (PO only)
30 mg
PO only
4–6h
Equivalent to PO morphine mg-for-mg. Often combined with acetaminophen (Norco).
Fentanyl IV
100 mcg
N/A
IV only*
0.5–1h
~100× morphine potency. Rapid onset (1–2 min IV). Short acting -good for procedures. Lipophilic → accumulates with repeated dosing.
Fentanyl patch
25 mcg/hr ≈ 60–90 mg PO morphine/day
-
72h
Only for opioid-tolerant patients. Takes 12–24h to reach steady state. Fever increases absorption → overdose risk.
DO NOT use standard equianalgesic ratios. Conversion is non-linear -becomes dramatically more potent at higher morphine equivalents. Always consult pharmacy or pain service for methadone conversions. Long QTc risk.
Quick Conversion Math
Morphine IV to PO: multiply by 3 (10 mg IV = 30 mg PO)
Hydromorphone IV to PO: multiply by 5 (1 mg IV = 5 mg PO)
Morphine PO to oxycodone PO: multiply by 0.67 (30 mg morphine = 20 mg oxycodone)
Morphine PO to hydromorphone PO: divide by 4 (30 mg morphine = 7.5 mg hydromorphone)
💊 Steroid Equivalency Table
Steroid
Equivalent Dose
Relative Anti-inflammatory Potency
Relative Mineralocorticoid
Duration
Notes
Hydrocortisone (Solu-Cortef)
20 mg
1×
1×
Short (8–12h)
Physiologic replacement: 15–20 mg AM + 5–10 mg PM. Stress dose: 100 mg IV q8h. Has mineralocorticoid activity → fluid retention at high doses. Endocrine Society, 2016
Prednisone (Deltasone) / Prednisolone (Orapred)
5 mg
4×
0.6×
Intermediate (12–36h)
Most commonly prescribed oral steroid. Prednisone is a prodrug (converted to prednisolone in liver, use prednisolone in liver failure). COPD exacerbation: 40 mg PO × 5 days. REDUCE, 2013
Methylprednisolone (Solu-Medrol)
4 mg
5×
0.5×
Intermediate (12–36h)
Preferred IV steroid for most indications. Pulse dose: 1g IV daily × 3 days (lupus, vasculitis, MS flare). EULAR, 2020
Dexamethasone (Decadron)
0.75 mg
25–30×
0 (none)
Long (36–72h)
Most potent. No mineralocorticoid → no fluid retention. Best for cerebral edema, croup, meningitis. Does NOT cross-react with cortisol assay (use when cosyntropin stim test needed). de Gans, 2002
Fludrocortisone (Florinef)
N/A
10×
125×
Intermediate (18–36h)
Mineralocorticoid replacement only (primary AI, 0.05–0.2 mg daily). NOT used as anti-inflammatory. Not needed in secondary AI (aldosterone preserved). Endocrine Society, 2016
Quick Conversions
Prednisone 40 mg PO = methylprednisolone 32 mg IV = dexamethasone 6 mg = hydrocortisone 160 mg
Prednisone 5 mg = the classic "physiologic" equivalent dose
See full Corticosteroids topic → Complete guide with glucocorticoid vs mineralocorticoid potency, when to use which steroid, side effects, tapering protocols, and pimp questions.
CoreWards
Admission Orders & I-PASS
The admission order framework you use every admit, and the sign-out template that keeps your cross-cover partner safe overnight.
📋 Admission Order Template -ADC VANDALISML
Letter
Category
What to Order
A
Admit to
Service (medicine, ICU, telemetry), attending name, resident/intern name
Ad lib, bed rest, ambulate TID with assist, PT/OT consult, fall precautions
L
Labs
AM labs (BMP, CBC). Admission: BMP, CBC, LFTs, lactate, troponin, BNP, UA, blood cultures, coags -based on diagnosis. Type and screen if anemia/bleeding risk.
I
IV fluids
NS at ___mL/hr, or hep-lock (no maintenance fluids). See Fluid Guide.
Home meds reconciliation (continue, hold, adjust). New treatment meds. VTE prophylaxis (enoxaparin 40 SC daily or heparin 5000 SC q8h -every patient). Bowel regimen (PEG 3350 + senna if on opioids, not docusate). Insulin (basal-bolus, not just sliding scale). PRNs: acetaminophen 1g q6h, ondansetron 4 mg q6h, melatonin 3 mg qHS.
L
Lines / tubes / drains
IV access (PIV, central line), Foley (document indication -remove ASAP), NG tube, chest tube, drains
The 3 most commonly missed admission orders: (1) VTE prophylaxis -#1 preventable cause of inpatient death. (2) Insulin orders in diabetics (not just sliding scale). (3) Code status documentation.
🔄 I-PASS Sign-Out Template
I-PASS Study, 2014: I-PASS handoff reduced medical errors by 23% and preventable adverse events by 30%.
Letter
Component
Example
I
Illness severity
"Stable" / "Watcher" / "Unstable." Watcher = most important category -these patients might deteriorate overnight.
P
Patient summary
"65M with HFrEF, admitted for ADHF, on IV diuresis, down 3 kg." One sentence. Diagnosis + current treatment trajectory.
A
Action list
"Check PM BMP for K⁺ (on Lasix drip). Urology following for Foley, may call to remove. Waiting on blood culture final." What needs to happen overnight.
S
Situation awareness / contingency planning
"If SBP drops < 90 → hold Lasix drip, give 250 mL NS bolus, recheck BMP, call me if doesn't improve. If K⁺ < 3.5 → replete 40 mEq IV KCl." If-then statements.
S
Synthesis by receiver
Cross-cover reads back key action items and contingencies. Asks questions. Closed-loop communication.
The "S" (situation awareness) is the most important part. Don't just list problems -tell your cross-cover what might go wrong and what to do about it. "If X happens → do Y" saves lives at 3 AM.
CoreQuick Reference
IV Fluid Guide
Which fluid, how much, and when. NS vs LR vs D5 vs albumin -the answer depends on the clinical scenario. Stop giving everyone "NS at 125."
Preferred resuscitation fluid for most patients.SMART, 2018: balanced crystalloids (LR) reduced death, new renal failure, and persistent renal dysfunction vs NS. Less hyperchloremic acidosis.
D5W
0
0
0
None
252
Free water replacement (hypernatremia, DI). NOT for volume resuscitation (glucose is metabolized → leaves free water → distributes into all compartments). Correct hypernatremia: D5W or ½NS.
Adrenal crisis (dextrose + volume). DKA maintenance (once glucose < 250, switch from NS to D5NS to continue insulin).
D5W + NaHCO₃ (Bicarb drip)
Varies
0
0
NaHCO₃
Varies
Common recipe: 150 mEq NaHCO₃ (3 amps of 50 mEq) in 1L D5W → run at 150–200 mL/hr. Uses: • Salicylate (aspirin) toxicity -urine alkalinization (goal urine pH 7.5–8.0) enhances renal excretion • TCA overdose -serum alkalinization overcomes sodium channel blockade (wide QRS → give until QRS narrows) • Severe metabolic acidosis (pH < 7.1) -bridge while treating underlying cause • Hyperkalemia (temporizing -shifts K⁺ intracellularly, less reliable than insulin/glucose) • Rhabdomyolysis -urine alkalinization (goal urine pH > 6.5) prevents myoglobin precipitation in tubules • Tumor lysis syndrome -historically used for urine alkalinization (now rasburicase preferred) ⚠️ Do NOT mix with calcium in same line (precipitates). Monitor for hypernatremia, metabolic alkalosis, hypokalemia.
3% Hypertonic saline
513
513
0
None
1027
Symptomatic severe hyponatremia (seizures, coma): 100–150 mL bolus over 10–20 min. Also for cerebral edema (herniation). ICU only. Never give peripherally at high rates.
Fluid Categories -Resuscitation vs Maintenance vs Replacement vs Specialty
Category
Purpose
Fluids Used
Rate
Key Rules
🔴 Resuscitation (Volume expansion)
Restore intravascular volume in shock, sepsis, hemorrhage, severe dehydration
LR (preferred) SMART, 2018 NS (acceptable) Albumin 5% (if refractory)
Bolus: 500 mL–1L over 15–30 min. Sepsis: 30 mL/kg in first 3h.
• Isotonic fluids ONLY -~25% stays intravascular (¼ of crystalloid bolus), rest goes interstitial • Colloids (albumin): ~100% stays intravascular in healthy physiology. ⚠️ In sepsis/critical illness, capillary leak allows albumin to extravasate into interstitium → loses its advantage. This is why balanced crystalloids (LR) remain first-line for sepsis resuscitation, NOT albumin SAFE, 2004ALBIOS, 2014 • NEVER use D5W or ½NS for resuscitation -D5W: only ~8% stays intravascular (distributes as free water across all compartments). ½NS: only ~17% stays intravascular • Reassess after each bolus (JVP, lung exam, MAP, UOP, lactate) • Stop when target MAP ≥ 65 or signs of fluid overload
🟡 Maintenance (Daily needs)
Replace insensible losses + obligatory urine output in NPO patients who are euvolemic
Depends on deficit calculation and correction rate limits
• Hypernatremia: correct ≤ 10 mEq/L per 24h • Hyponatremia: correct ≤ 8 mEq/L per 24h (risk of ODS if too fast) • Match the fluid to the deficit -don't just give NS for everything
🟣 Specialty (Drug vehicles / specific protocols)
Carry medications or correct specific metabolic derangements
D5W + NaHCO₃ -bicarb drip (salicylate/TCA OD, rhabdo, acidosis) D5NS -DKA (when BG < 250, switch to D5 to continue insulin) D5W -drug carrier (amiodarone, many drips) Albumin 25% -oncotic pull in HF + hypoalbuminemia
Protocol-specific
• Bicarb drip: never mix with calcium in same line • DKA: D5 prevents hypoglycemia while insulin clears ketones • Some drugs are ONLY compatible with D5W (amiodarone, phenytoin)
⚠️ The #1 mistake: Using D5W or ½NS for volume resuscitation. 1L NS or LR → ~250 mL stays intravascular (25%) 1L ½NS → ~170 mL stays intravascular (17%) 1L D5W → ~83 mL stays intravascular (8%) -basically free water 1L Albumin 5% → ~1000 mL stays intravascular (100%) in healthy capillaries. In sepsis/capillary leak → albumin extravasates and this advantage is lost. First-line resuscitation = balanced crystalloids (LR). Albumin is reserved for specific indications (SBP, HRS, post-LVP) or refractory shock after crystalloid.
Colloids
Fluid
Use
Do NOT Use
Albumin 5%
SBP (1.5 g/kg day 1, 1 g/kg day 3). HRS (with midodrine + octreotide). Post-LVP > 5L (6–8 g/L removed). Sepsis (if not responding to crystalloid).
Volume expansion with minimal fluid volume (useful in HF + hypoalbuminemia → draws fluid from interstitium into intravascular space).
Same as 5%. Expensive.
Avoid hydroxyethyl starch (HES / Voluven) -increases AKI and mortality in critically ill patients VISEP, 20086S, 2012. FDA black box warning. Use crystalloids or albumin instead.
Quick Decision Guide
Scenario
Best Fluid
Sepsis / Shock resuscitation
LR boluses (30 mL/kg). Albumin if refractory.
DKA
NS initially (volume-depleted + hyponatremia common). Switch to D5½NS when glucose < 250.
Hypernatremia
D5W or ½NS (free water). Correct ≤ 10 mEq/L per 24h.
Hyponatremia (symptomatic)
3% hypertonic saline 100–150 mL bolus. ≤ 8 mEq/L per 24h.
Metabolic alkalosis (Cl-responsive)
NS (provides chloride to correct the alkalosis).
Maintenance (NPO patient)
D5½NS + 20 KCl at 75–125 mL/hr (or use 4-2-1 rule).
⚠️ The classic intern mistake: Admitting a patient and reflexively ordering "D5½NS at 125 mL/hr" without asking: can this patient eat? Are they fluid-restricted? Three days later they're 5 kg up with new pulmonary edema.
Rule: If the patient can eat → no maintenance fluids. If they can't eat but are volume overloaded → no maintenance fluids. Maintenance fluids are ONLY for the NPO + euvolemic patient.
TBW = weight (kg) × 0.6 (male) or × 0.5 (female). Replace deficit over 48–72h (correct ≤ 10 mEq/L per 24h). Add ongoing losses (insensible + urine).
Which Fluid for Hypernatremia? -Decision Tree
The deficit formula tells you how much. This tells you which fluid:
Volume Status
Step 1
Step 2 (Correction)
Free Water per Liter
Hypovolemic (most common -dehydration, vomiting, diarrhea, poor PO intake)
NS bolus first -restore intravascular volume. NS is "hypotonic" relative to the patient's serum Na⁺ (154 vs 160+), so it will still lower Na⁺ slightly.
Once hemodynamically stable → switch to ½NS (provides Na⁺ + free water)
½NS = 500 mL free water/L NS = 0 mL (but still relatively hypotonic to patient)
Euvolemic (pure water loss -diabetes insipidus, insensible losses, inadequate water intake)
D5W -pure free water replacement. No volume deficit to correct first.
⚠️ Classic pimp question: "Na⁺ is 158 and the patient is hypotensive -do you start D5W?" NO. D5W is free water -only ~8% stays intravascular. A hypotensive patient needs volume first (NS bolus), then switch to ½NS or D5W for Na⁺ correction once hemodynamically stable. Fix the volume, then fix the sodium.
Free water content of common fluids: D5W: 1000 mL free water per liter (100%) ¼NS (0.2%): 750 mL free water per liter (75%) ½NS (0.45%): 500 mL free water per liter (50%) NS (0.9%): 0 mL free water per liter (0% -isotonic) Oral water / NG flushes: 1000 mL per liter (100%) -best option if patient can tolerate PO
CoreQuick Reference
Lab Interpretation
What's actually important in the CBC, BMP, LFTs, and coags -not just the reference ranges, but what the abnormalities mean clinically and what to do about them.
📐 Classic Fishbone Diagrams
BMP Fishbone
AG = Na⁺ − (Cl⁻ + HCO₃⁻) | Normal: 8–12 | BUN:Cr > 20:1 → pre-renal AKI
BMP (8 values): Na⁺, K⁺, Cl⁻, HCO₃⁻, BUN, Cr, Glucose, Ca²⁺ CMP adds (6 more): Albumin, Total protein, AST, ALT, ALP, Total bilirubin When to order CMP over BMP: New admission, liver disease, medications with hepatotoxicity, TPN, unexplained AMS, jaundice
Bile duct obstruction (stone, mass, stricture) → RUQ US first. Intrahepatic: PBC, PSC, drug-induced, infiltrative. GGT confirms hepatic origin of alk phos.
Mixed
↑↑
↑↑
↑
Drug-induced, granulomatous hepatitis
AST > ALT (> 2:1)
Ratio > 2:1
Alcoholic hepatitis (classic ratio). Also: cirrhosis, Wilson disease, rhabdomyolysis (AST from muscle -check CK).
"LFTs" is a misnomer. AST, ALT, and alk phos measure liver INJURY, not function. True liver FUNCTION markers: albumin (synthesis), INR (clotting factor synthesis), bilirubin (conjugation/excretion). A patient with normal AST/ALT but INR of 3 and albumin of 2 has severe liver dysfunction.
🔬 Coags, Inflammatory Markers & More
Lab
Normal
Clinical Meaning
PT / INR
PT 11–13.5s INR 0.9–1.1
Extrinsic pathway (factors VII, X, V, II, fibrinogen). Elevated: warfarin, liver disease, DIC, vitamin K deficiency. INR is the standardized version of PT.
aPTT
25–35s
Intrinsic pathway (XII, XI, IX, VIII). Elevated: heparin (therapeutic monitoring), hemophilia (VIII or IX deficiency), lupus anticoagulant (paradoxically prolonged but prothrombotic), DIC.
Fibrinogen
200–400 mg/dL
Low: DIC (consumed), liver failure. High: acute phase reactant (inflammation). Most specific lab for DIC severity. Critical value < 100 → give cryoprecipitate.
D-dimer
< 500 ng/mL
Sensitive but NOT specific. Elevated in PE, DVT, DIC, surgery, pregnancy, cancer, infection, trauma -basically any hospitalized patient. Useful to RULE OUT PE/DVT when low pretest probability (Wells ≤ 4).
Lactate
< 2.0 mmol/L
↑: tissue hypoperfusion (sepsis, shock -Type A) or impaired clearance (liver failure, metformin -Type B). Lactate > 4 in sepsis → mortality > 30%. Trend is more important than single value.
Non-specific inflammation. Very high (> 100): infection (endocarditis, osteomyelitis), autoimmune (SLE, PMR/GCA), malignancy (myeloma). Slow to rise and slow to fall. SLE flare: ↑ ESR + normal CRP.
CRP
< 3 mg/L
Faster marker of inflammation than ESR. Rises within 6h, peaks 48h. Good for tracking treatment response. CRP elevated in SLE = think infection, not flare.
Troponin (hs-TnI)
Varies by assay
Myocardial injury. NOT specific for MI -elevated in: PE, HF, sepsis, CKD (chronic elevation), myocarditis, takotsubo, cardioversion. Trend matters: rise-and-fall pattern = acute injury. Stable low-level = chronic (CKD, HF).
BNP / NT-proBNP
BNP < 100 NT-proBNP < 300
Rule out HF: BNP < 100 or NT-proBNP < 300 makes HF very unlikely. Falsely low: obesity (adipose tissue clears BNP). Falsely high: Afib, PE, CKD, age. Why ↗
SafetyQuick Reference
Drug Interactions
The combinations that actually hurt patients on the wards. QT prolongation, serotonin syndrome, and the high-risk pairs you need to catch before they cause harm.
⚡ QT-Prolonging Drugs
QTc > 500 ms = high risk for torsades de pointes. Risk multiplies when combining QT-prolonging drugs + hypokalemia + hypomagnesemia. Check ECG, K⁺, and Mg²⁺ before and during treatment.
IV haloperidol has higher QT risk than IM/PO. Check QTc before and during use. Hold if QTc > 500.
Antidepressants
Citalopram, escitalopram (dose-dependent), TCAs
Citalopram max 20 mg in age > 60 (FDA). TCAs: QRS widening + QT prolongation.
Other
Methadone, sumatriptan, donepezil
Methadone: always check QTc at baseline and periodically. Dose-dependent.
Risk Multipliers
Hypokalemia -replete K⁺ > 4.0 if on QT drugs
Hypomagnesemia -replete Mg²⁺ > 2.0
Hypocalcemia
Bradycardia (more time in repolarization)
Female sex (baseline longer QT)
Combining ≥ 2 QT-prolonging drugs -the risk is synergistic, not just additive
🧠 Serotonin Syndrome
Onset within hours of adding/increasing a serotonergic drug. Classic triad: AMS + autonomic instability + neuromuscular excitation (CLONUS is the most specific sign).
Dangerous Combinations
Drug A
+ Drug B
Risk Level
SSRI / SNRI
MAOI (phenelzine, tranylcypromine, selegiline)
CONTRAINDICATED -14-day washout required between SSRI and MAOI
SSRI / SNRI
Linezolid (Zyvox) (weak MAOI)
HIGH RISK -hold SSRI if linezolid essential. Consult ID + psychiatry.
SSRI / SNRI
Tramadol
MODERATE -very common ward combination. Avoid if possible. Use alternative analgesic.
SSRI / SNRI
Fentanyl (Sublimaze) (especially IV/patch)
MODERATE -serotonergic at higher doses. Monitor closely.
SSRI / SNRI
Triptans (sumatriptan)
LOW-MODERATE -FDA warning but actual risk is very low. Can use with monitoring.
SSRI / SNRI
Methylene blue (IV)
HIGH RISK -methylene blue is an MAOI. Hold SSRI ≥ 2 weeks before elective use.
SSRI / SNRI
Ondansetron (Zofran)
LOW -5-HT3 antagonist. Theoretical risk. Clinically rare. Generally safe to use.
Do NOT co-administer. Multiple reported deaths. Reduce colchicine dose or hold during macrolide.
Metformin + IV contrast
Lactic acidosis (if contrast causes AKI → metformin accumulates)
Updated (ACR 2022): If eGFR ≥ 45, no need to hold metformin. If eGFR 30–44, hold day of contrast, resume 48h later if Cr stable. eGFR < 30 → hold regardless. Old teaching to hold in all patients is outdated.
Digoxin + amiodarone
Digoxin toxicity (amio increases dig levels ~70%)
Reduce digoxin dose by 50% when starting amiodarone. Check dig level in 1 week.
Carbamazepine (Tegretol) + many drugs
↓ levels of warfarin, DOACs, OCP, steroids (potent CYP3A4 inducer)
Check for interactions with all co-medications. May need dose increases of affected drugs.
Reduce azathioprine dose by 75% if must co-administer. Or use mycophenolate instead. Monitor CBC closely.
Carbapenems + valproate (Depakote) AVOID
VPA levels drop 50–90% within 24–48h → breakthrough seizures / status epilepticus (inhibition of acylpeptide hydrolase blocks VPA-glucuronide recycling)
Avoid co-administration. Dose-escalating VPA does NOT rescue. If carbapenem is mandatory (CRE, ESBL), bridge AED to levetiracetam. Applies to meropenem, imipenem, ertapenem, doripenem.
Do NOT co-administer. Multiple reported deaths. Especially high-risk in elderly, renal impairment, low-dose weekly MTX for RA. Leucovorin rescue if accidentally given.
Clopidogrel (Plavix) + omeprazole / esomeprazole
↓ clopidogrel activation (CYP2C19 inhibition prevents clopidogrel → active metabolite)
FDA warning 2009. Use pantoprazole (minimal CYP2C19 effect) if PPI needed. Clinical significance debated (COGENT showed no difference) but boards test this, know it.
Warfarin + metronidazole (Flagyl)
↑↑ INR (CYP2C9 inhibition, same as TMP-SMX and fluconazole)
INR can double within 3–5 days. Reduce warfarin dose by 25–50% empirically. Check INR in 3 days.
Warfarin + NSAID
↑↑ GI bleed risk (platelet inhibition + gastric erosion + displacement from albumin)
Avoid combination when possible. If unavoidable, use shortest course, add PPI, avoid ketorolac entirely. Acetaminophen is the safer analgesic.
Spironolactone / eplerenone + TMP-SMX
Hyperkalemia (trimethoprim acts like amiloride on distal tubule + MRA blocks aldosterone)
Check K⁺ within 3–5 days. Elderly + renal impairment at highest risk. Consider alternative antibiotic (nitrofurantoin for UTI).
Rifampin + many (warfarin, DOACs, OCP, steroids, methadone, CNIs, statins)
↓↓ drug levels (potent CYP3A4, CYP2C9, P-gp INDUCER, broadest drug interaction profile of any common drug)
Review every co-medication when starting rifampin. Increase dose or switch. OCP failure is common, counsel on backup contraception. Effect persists 2 weeks after stopping.
Check lithium level within 5–7 days of starting any of these. Narrow therapeutic window (0.6–1.2 mEq/L). Hold lithium if acute illness/volume depletion.
Hypoglycemia (mechanism varies, sulfa cross-reactivity + CYP2C9 inhibition for TMP-SMX)
Monitor fingersticks q4–6h during first 48h. Reduce sulfonylurea dose or hold. Elderly at highest risk. Gatifloxacin causes both hypo- AND hyperglycemia (withdrawn in US).
Levothyroxine + PPI / calcium / iron / sucralfate / bile acid binders
Separate by ≥ 4 hours. Levothyroxine should be taken 30–60 min before breakfast, fasting. PPI effect is smaller but real in gastric-acid-dependent absorption.
Do NOT combine. Single-agent RAAS is adequate. Exception: add-on spironolactone is NOT dual blockade and is indicated in HFrEF.
, , VERY COMMON (you'll see these every day on the wards) , ,
Opioid + benzodiazepine
Respiratory depression, oversedation, death (FDA black box warning 2016). Leading cause of accidental overdose death.
Avoid combination when possible. If needed: lowest effective doses, observe, naloxone at bedside. Be especially cautious in elderly, opioid-naïve, COPD, OSA.
Opioid + alcohol / sedatives
Synergistic respiratory depression
Counsel patients. Caution in discharge planning with opioid prescriptions.
Aspirin + ibuprofen (or other NSAIDs)
Ibuprofen blocks the COX-1 site where ASA binds irreversibly → ↓ ASA antiplatelet effect
Dose ASA at least 2h before ibuprofen (or use acetaminophen / COX-2 inhibitor instead). Critical in patients with cardiac stents.
Warfarin + acetaminophen (APAP > 2g/day chronic)
↑ INR (mechanism unclear but consistent signal; risk rises with chronic 3–4g/day)
Check INR 3–5 days after starting chronic APAP. Most patients tolerate ≤ 2g/day without issue.
Warfarin + fluoroquinolones (cipro, levo, moxi)
↑ INR (disruption of gut flora producing vit K + mild CYP effects)
Check INR within 3–5 days of starting. Common outpatient over-anticoagulation scenario.
Warfarin + SSRI / SNRI
↑ bleed risk (platelet function + gastric erosion + CYP effects for some SSRIs)
Prefer sertraline, citalopram (least CYP interaction). Add PPI if GI bleed history. Monitor INR for fluoxetine/fluvoxamine (CYP2C9).
Hypertensive crisis or serotonin syndrome (linezolid is a weak MAOI)
Counsel on tyramine foods during linezolid. Screen OTC decongestants. Use morphine/hydromorphone instead of meperidine.
Digoxin + IV calcium HISTORIC WARNING
"Stone heart", fatal arrhythmia from intracellular Ca overload (classic teaching)
Modern data suggests risk is overstated but most clinicians still avoid. If hypocalcemia AND dig toxicity together → give Digibind first, then cautious calcium.
Use fenofibrate instead (much lower rhabdo risk). Or statin + ezetimibe.
Colchicine + statin
Myopathy (independent muscle toxicity, additive)
Watch for muscle pain, weakness. Check CK if symptomatic. Higher risk with atorvastatin + high-dose colchicine.
Isoniazid + alcohol
Hepatotoxicity (additive)
Counsel abstinence during TB treatment. Screen LFTs monthly.
Metronidazole + alcohol / cefoperazone + alcohol
Disulfiram-like reaction (flushing, nausea, palpitations), contested for metronidazole but classic teaching
Counsel patients to avoid alcohol during and 3 days after metronidazole. Applies to any alcohol source (mouthwash, cough syrup).
Disulfiram + alcohol
Intended disulfiram reaction, severe flushing, hypotension, vomiting, rarely cardiovascular collapse
Never give disulfiram without patient consent. Watch for hidden alcohol (cough syrup, IV meds in propylene glycol).
Tyramine-rich food + MAOI
Hypertensive crisis (stroke, MI), classic "wine and cheese" reaction
Avoid aged cheese, cured meats, red wine, fava beans, soy sauce. Counsel thoroughly when starting any MAOI (phenelzine, tranylcypromine, selegiline, linezolid at high doses).
Always ask patients about herbal supplements. Discontinue St. John's Wort ≥ 2 weeks before starting SSRI.
Ticagrelor + strong CYP3A4 inhibitors
↑ ticagrelor levels → bleeding
Avoid ketoconazole, clarithromycin, ritonavir with ticagrelor. Clopidogrel is the alternative (but has its own PPI interaction).
Cisplatin + aminoglycoside / loop diuretic
Nephrotoxicity + ototoxicity (synergistic)
Pre-hydrate before cisplatin. Avoid concurrent nephrotoxins. Audiometry baseline.
Methadone + benzodiazepine / alcohol
Respiratory depression, overdose death (also QT prolongation additive with other QT drugs)
High-risk combination in MAT programs. Start low, monitor carefully.
🧬 CYP450 & P-gp Cheat Sheet
Mental model:Inhibitor → drug levels ↑ (toxicity) within days. Inducer → drug levels ↓ (treatment failure) over 1–2 weeks. Always check when starting/stopping ANY antifungal, antibiotic, anticonvulsant, or antiretroviral.
Azithromycin does NOT inhibit CYP3A4, the safe macrolide when you need a statin to stay on board. Erythromycin and clarithromycin do inhibit.
Pravastatin and rosuvastatin are not CYP3A4 substrates, preferred statins when using strong CYP3A4 inhibitors.
Dabigatran is the only dialyzable DOAC, relevant when P-gp inhibitor + AKI causes toxicity.
Smoking induces CYP1A2, smokers need higher doses of theophylline, olanzapine, clozapine. Dose drops if they quit.
EmergentQuick Reference
Anticoagulation Reversal
When the patient on blood thinners is bleeding or needs emergency surgery. Know the agent, know the antidote, know the dose. Every minute counts in life-threatening hemorrhage.
First-line for life-threatening bleed. Always give with vitamin K 10 mg IV (slow push over 10 min -anaphylaxis risk if fast). PCC effect is temporary (6–8h); vitamin K provides sustained reversal (6–24h). FFP is second-line (large volume, slow, infection risk).
Warfarin
Vitamin K (phytonadione) NON-EMERGENT
INR > 10, no bleed: 2.5–5 mg PO Minor bleed: 5–10 mg IV slow
6–24h
PO preferred for non-emergent. IV onset faster but anaphylaxis risk. SubQ absorption is erratic -avoid. Recheck INR in 6–12h.
Dabigatran (Pradaxa)
Idarucizumab (Praxbind)
5g IV (given as 2 × 2.5g boluses)
Minutes
Specific monoclonal antibody fragment. Complete reversal within minutes. Single use. If unavailable: 4F-PCC 50 units/kg (partial effect). Hemodialysis removes ~60% of dabigatran (it's dialyzable -unique among DOACs).
Rivaroxaban (Xarelto) Apixaban (Eliquis) Edoxaban: andexanet NOT approved, use 4F-PCC 50 units/kg
Recombinant modified Factor Xa decoy. Approved for apixaban and rivaroxaban only (not edoxaban, not LMWH, not fondaparinux). Very expensive (~$50,000/dose).Dose selection:high dose only if the last dose was apixaban > 5 mg or rivaroxaban > 10 mg AND taken within 8h (or timing unknown). Everything else gets the low dose, including any dose taken ≥ 8h ago. Increased thromboembolism after reversalANNEXA-I, 2024. If unavailable: 4F-PCC 50 units/kg (reasonable alternative, much cheaper).
Unfractionated heparin
Protamine sulfate
1 mg per 100 units heparin given in last 2–3h. Max 50 mg.
5 min
Full reversal. Risk: hypotension, bradycardia, anaphylaxis (especially in patients with fish allergy, prior protamine, or NPH insulin use -NPH contains protamine).
Enoxaparin (LMWH)
Protamine sulfate
1 mg per 1 mg enoxaparin (if within 8h of dose). 0.5 mg per 1 mg if 8–12h.
5 min
Only ~60% reversal (protamine neutralizes anti-IIa but not anti-Xa activity of LMWH). If still bleeding → consider 4F-PCC.
tPA / fibrinolytics
Cryoprecipitate + TXA
Cryo 10 units (fibrinogen > 200). TXA 1g IV over 10 min.
Minutes
Replenish fibrinogen (consumed by tPA). TXA is antifibrinolytic. Also give platelets if < 100K. Aminocaproic acid is alternative to TXA.
🔧 Pre-Procedure Hold Times
Drug
Hold Before Procedure
Resume After
Bridging Needed?
Warfarin (Coumadin)
5 days (INR < 1.5 for most procedures)
12–24h post (once hemostasis confirmed)
Only if high thrombotic risk: mechanical mitral valve, recent VTE (< 3 mo), CHA₂DS₂-VASc ≥ 7. Use enoxaparin 1 mg/kg BID. Most patients do NOT need bridgingBRIDGE, 2015: bridging increased bleeding without reducing thromboembolism.
Apixaban (Eliquis)
48h (72h if high bleed risk or CrCl < 30)
24–48h post
No bridging needed (short half-life, rapid onset on resumption).
Rivaroxaban (Xarelto)
48h (72h if CrCl < 30)
24–48h post
No bridging.
Dabigatran (Pradaxa)
48–72h (CrCl 50–80). 96h+ if CrCl < 50.
24–48h post
No bridging. Longer hold in renal impairment (renally cleared).
Enoxaparin (therapeutic)
24h
24–48h post
N/A
Heparin drip
4–6h (check aPTT)
When safe per surgeon
N/A
Aspirin (primary prevention)
7 days
24h post
N/A
Aspirin (cardiac stent)
DO NOT STOP
N/A
Continue through procedure unless life-threatening bleed risk. Stopping ASA within 6 months of DES → stent thrombosis → MI.
Clopidogrel (Plavix)
5 days
24h post
Consult cardiology before holding if recent stent.
RoundsRx Infographic Series · #19 · Hematology · PDF 153 KB
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Method 1 -From Sliding Scale Usage
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Method 2 -Weight-Based (Insulin-Naive)
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📋 Quick Reference
Scenario
Recommendation
Patient eating normally
Full basal-bolus-correction: 50% basal (glargine QHS) + 50% nutritional (lispro AC meals) + correction scale
NPO
Continue basal (reduce 20–50% if concerned). Hold nutritional. Correction-only sliding scale q6h. Never hold basal completely in Type 1.
Tube feeds (continuous)
Basal (glargine) + correction q6h. Or NPH q12h + correction. Or 70/30 insulin q12h.
On steroids
↑ TDD by 20–40%. Steroids cause afternoon/evening hyperglycemia → increase lunch and dinner nutritional doses more than basal.
Transitioning from drip
24h drip total × 80% = TDD. Split 50/50. Give SubQ basal 2–4h BEFORE stopping drip (overlap for glargine onset).
Correction factor
1800 ÷ TDD = how many mg/dL 1 unit drops glucose. Example: TDD 60 → CF = 30 → 1 unit drops BG by 30 mg/dL.
CoreQuick Reference
Radiology Quick Reference
Systematic CXR interpretation, common CT findings, and when to order what. You don't need to be a radiologist -you need to not miss the dangerous stuff.
✅ Is This a Good Film? (RIPE)
Check adequacy before you interpret. A technically poor film fakes pathology, an underpenetrated or shallow-inspiration film mimics edema and cardiomegaly, a rotated film fakes a widened mediastinum. If you read findings off a bad film, you act on artifact. Run RIPE first, then ABCDE.
Check
What "good" looks like
If it's off (and how it fools you)
R -Rotation
The spinous processes sit exactly midway between the medial (sternal) ends of both clavicles. Equal distance = no rotation. Which way: the spinous-to-clavicle gap is wider on the side the patient is rotated toward (it drifts toward the clavicle on the side turned toward the film).
If the spinous process is closer to one clavicle, the patient is rotated. Rotation falsely widens the mediastinum (mimics dissection/mass), makes one lung look denser and the other more lucent (mimics effusion, mass, or pneumothorax), and distorts the heart and hilar contours. Do not call mediastinal width or asymmetric lucency on a rotated film.
I -Inspiration
Count 9–10 posterior ribs (or 5–6 anterior ribs) above the diaphragm at the midclavicular line. The diaphragm should sit at about the 10th posterior rib.
Shallow / expiratory film: the bases crowd and look white (mimics edema, basal atelectasis, or infiltrate), the heart is squeezed transversely and looks falsely enlarged, and vascular markings look exaggerated. Hyperexpansion (> 11 ribs, flat diaphragms) points to COPD / air trapping.
P -Projection & position
PA, upright, with the side marker present and the scapulae rotated off the lung fields (hands-on-hips technique). Projection = the direction the beam travels (PA, back-to-front; AP, front-to-back). Position = how the patient is placed (upright vs supine vs lateral decubitus).
AP magnifies the heart, so cardiomegaly cannot be called (see box below). Supine loses the air-fluid levels and gravity layering you need to size an effusion or spot a pneumothorax. Lordotic distorts the heart and apices (see box below). On AP/portable the scapulae usually overlie the upper lungs.
E -Exposure (penetration)
You should just barely see the lower thoracic vertebrae and disc spaces through the heart, and trace the left hemidiaphragm behind the heart all the way to the spine. Bronchovascular markings visible to within ~2 cm of the pleura.
Underpenetrated (too white): lungs look hazy, mimicking infiltrate or edema; vessels look exaggerated. Overpenetrated (too dark): subtle infiltrates, lines, a small pneumothorax, or a nodule disappear because the markings are burned out.
Why AP is no good for the heart. On a PA film the beam travels back-to-front and the detector sits against the anterior chest. The heart lies anteriorly, so it is close to the detector and barely magnified, giving a true size (this is why CTR > 0.5 = cardiomegaly only on PA). On an AP film (usually portable, supine, in a sick patient) the detector is behind the patient, so the heart sits far from it and the diverging beam magnifies it by ~15–20%: a normal heart looks big. Supine positioning also raises the diaphragms (lower lung volumes), redistributes flow to the upper lobes (a "cephalization" that is not real failure), and widens the mediastinum. Never diagnose cardiomegaly or mediastinal widening on an AP/portable film; read it as "AP, limited" and correlate.
Lordotic films.Named for lordosis, the spine's normal inward curve; the patient arches back so the beam angles up through the chest. The beam strikes the chest angled upward (patient leaning back, or beam angled cephalad). How to spot it: the medial ends of the clavicles ride high, projected above the lung apices and pointing upward; the anterior ribs look horizontal while the posterior ribs angle steeply; the heart looks foreshortened, rounded, and falsely enlarged; the diaphragm may look flat. How it fools you: the foreshortened heart mimics cardiomegaly, and the apices and RML/lingula are distorted, so you can over-call or miss a consolidation. The useful version: a deliberate apical lordotic view throws the clavicles off the apices to look for apical disease (TB, Pancoast tumor).
🩻 Systematic CXR -ABCDE
Step
What to Check
Key Findings
A -Airway
Trachea (midline?), carina, mainstem bronchi
Tracheal deviation: TOWARD collapse/atelectasis, AWAY from tension PTX/large effusion. ETT tip: 2–4 cm above carina.
CTR > 0.5 = cardiomegaly (on PA film). Boot-shaped → RVH. Water-bottle → pericardial effusion. Widened mediastinum > 8 cm → aortic dissection, aortic aneurysm, lymphoma.
D -Diaphragm
Costophrenic angles (blunted?), free air under diaphragm, elevated hemidiaphragm
Blunted CP angles: ≥ 200 mL effusion (lateral decubitus more sensitive). Free air under diaphragm → perforated viscus (surgical emergency). Elevated hemidiaphragm → phrenic nerve palsy, hepatomegaly, subpulmonic effusion.
E -Everything else (lungs)
Lung fields: compare L vs R, upper vs lower. Infiltrates, masses, pneumothorax, lines/tubes
White-out: large effusion (meniscus), complete atelectasis (shifted structures toward), massive PNA. PTX: visceral pleural line + absent lung markings. Kerley B lines: pulmonary edema. Check all lines: ETT, central line, NG tube, chest tube, pacer wires.
Also confirm before reading: right patient, right date, and prior films available for comparison. A single film is a snapshot; the old film tells you what is new.
🔎 Named CXR Signs -What You Actually See
How to use this: the ABCDE tab is how you walk the film; this tab is the lookup for when a pattern jumps out at you. Each row tells you what the sign looks like, then what it means and why, so the finding actually changes your management.
Volume loss / collapse (atelectasis)
Sign
What you actually see
Pathology & why
Rib crowding
Rib interspaces on one side visibly narrower than the other; ribs look bunched together
Volume loss. The collapsed lung pulls the chest wall inward, narrowing the gaps.
Mediastinal shift toward
Trachea and heart border pulled to the same side as the white opacity
Collapse. Lost volume creates negative space that drags mobile midline structures in. (Shift away = something is pushing: see next table.)
Elevated hemidiaphragm
One dome sits higher than expected (normally the right is ~1–2 cm above the left, so look for more than that)
Lower-lobe volume loss (also phrenic palsy, subpulmonic effusion, hepatomegaly). Diaphragm rises to fill the vacated space.
Displaced fissure
The thin white line of a fissure pulled out of its normal position toward the opacity
Lobar collapse. The fissure migrates with the shrinking lobe; the most direct sign of which lobe collapsed.
Pushing pathology (volume added)
Sign
What you actually see
Pathology & why
Mediastinal shift away
Trachea and heart pushed to the opposite side of the white-out
Large effusion or mass. Volume is being added and shoves the mediastinum off midline. Pairs with the meniscus sign for effusion.
Deep sulcus sign
On a supine film, one costophrenic angle is abnormally deep and very black, with a sharp lateral gutter
Pneumothorax. In a supine patient, air rises anterobasally (the least dependent spot) and deepens the sulcus, where a classic apical pleural line may be absent.
Visible pleural line + absent markings
A thin white line parallel to the chest wall with pure black (no vascular markings) beyond it
Pneumothorax. The line is the visceral pleura; the black void is free pleural air with no lung in it.
Trachea away + flat/low diaphragm
Everything pushed off midline, hemidiaphragm flattened or pushed down
Tension pneumothorax. Air under pressure pushes the mediastinum and kinks venous return. This is a clinical diagnosis; decompress before you wait on the film.
Air-space, interstitial & pleural
Sign
What you actually see
Pathology & why
Air bronchogram
Dark, branching tube-like lucencies running through a white patch of lung
Alveolar filling (pneumonia, pulmonary edema, ARDS). Alveoli fill with fluid or pus but the bronchi stay air-filled, so they show up dark against the white.
Silhouette sign
A border that should be a crisp line (heart edge or diaphragm) is blurred or erased
Localizes the disease. Two same-density structures in contact lose the line between them: lost right heart border = RML, lost left heart border = lingula, lost diaphragm outline = lower lobe.
Kerley B lines
Short (1–2 cm), thin horizontal lines at the periphery, perpendicular to and touching the pleural surface (usually at the bases)
Interstitial edema or lymphangitic spread. Fluid or cells thicken the interlobular septa enough to be seen.
Bat-wing / butterfly
Symmetric fluffy white haze fanning out from both hila, sparing the periphery
Cardiogenic pulmonary edema. Fluid collects centrally first before reaching the outer lung.
Meniscus sign
A white fluid density whose upper edge curves upward (concave-up) along the lateral chest wall
Pleural effusion. Free fluid tracks up the dependent space; surface tension gives the upward curve. Blunted costophrenic angle is the earliest version (~200 mL on an upright film).
Classic spot-diagnoses
Sign
What you actually see
Pathology & why
Free air under diaphragm
A thin black crescent of air between the white diaphragm and the liver, on an upright film
Perforated viscus (surgical emergency). Free intraperitoneal air rises under the dome. Needs an upright or left-lateral-decubitus film to be seen.
Continuous diaphragm sign
The full diaphragm line is visible across the midline, including the central part normally hidden by the heart
Pneumomediastinum. Air outlines the central diaphragm from above, completing the line.
Westermark sign
A focal region of lung that looks darker (fewer vessels) than the rest
Pulmonary embolism. Clot causes oligemia distal to it. Insensitive but a classic boards answer.
Hampton hump
A wedge-shaped white density at the lung periphery, base on the pleura, apex pointing toward the hilum
PE with infarction. The wedge is the infarcted lung territory.
Boot-shaped heart
Cardiac apex lifted up off the diaphragm with a concave upper-left border, shaped like a boot
Tetralogy of Fallot. RV hypertrophy tilts the apex upward.
Water-bottle heart
Globular, symmetrically enlarged cardiac silhouette with a smooth flask shape
Large pericardial effusion. Fluid in the pericardial sac balloons the silhouette; correlate with echo, not CXR alone.
Small airway disease. Centrilobular nodules + tree-in-bud = active infectious bronchiolitis. Isolate for TB. Get sputum AFB × 3.
CT Abdomen -free air
Perforated viscus
Surgical emergency. Most common: perforated duodenal ulcer, perforated diverticulitis, perforated appendix. Get surgical consult immediately.
CT Abdomen -portal venous gas
Mesenteric ischemia, bowel necrosis
Ominous sign. Also pneumatosis intestinalis (air in bowel wall). Lactate elevated. Surgical emergency. CT angiography for mesenteric vessels.
CT Abdomen -dilated bowel
SBO vs ileus
SBO: transition point (dilated → decompressed), small bowel > 3 cm. Ileus: diffusely dilated, no transition point. SBO → surgical consult. Toxic megacolon (C. diff): colon > 6 cm.
📋 What Imaging to Order
Clinical Question
Best Study
Notes
Chest pain -ACS ruled out, PE suspected
CTPA
Wells score first. If low probability → D-dimer. If D-dimer positive or high probability → CTPA. V/Q scan if contrast allergy or CKD.
Stroke symptoms (< 24h)
CT Head without contrast (rule out hemorrhage) → CTA head/neck (LVO) → MRI DWI (confirm ischemic)
CT to rule out bleed before tPA. CTA for large vessel occlusion (thrombectomy candidate). MRI DWI most sensitive for acute ischemia.
Abdominal pain
CT abdomen/pelvis with IV contrast
Most versatile. RLQ pain in young female → consider US first (ovarian pathology, avoid radiation). RUQ pain → RUQ US first (gallstones, cholecystitis).
GI bleed -upper vs lower
EGD first. CT angiography if massive/unstable.
CTA abdomen/pelvis if active bleeding (extravasation). Tagged RBC scan if slow intermittent bleed. Colonoscopy within 24h for lower GIB.
Renal colic / stones
CT abdomen/pelvis WITHOUT contrast
Non-contrast CT is gold standard for stones (contrast obscures them). US is first-line in pregnancy.
Biliary disease
RUQ ultrasound
First-line for gallstones, cholecystitis. MRCP for common bile duct stones if US equivocal. HIDA scan for acalculous cholecystitis (EF < 35%).
DVT suspected
Compression ultrasound
Sensitivity > 95% for proximal DVT. If negative but high clinical suspicion → repeat in 5–7 days or whole-leg US.
Aortic dissection
CTA chest/abdomen/pelvis
Gold standard. TEE is alternative (especially if too unstable for CT). D-dimer < 500 has high NPV for dissection.
Pleural effusion workup
CXR → US-guided thoracentesis
Lateral decubitus CXR to confirm free-flowing. Bedside US for marking. CT chest with contrast if concern for malignancy, empyema, or loculated.
Pulmonary nodule found
Follow Fleischner criteria
Size, morphology (solid vs GGO vs part-solid), risk factors determine follow-up interval. Part-solid nodules have highest malignancy risk. PET-CT for solid nodules ≥ 8 mm.
Contrast contraindications: eGFR < 30 (risk of CIN -but don't withhold if life-threatening indication like PE, dissection, stroke), contrast allergy (premedicate: prednisone 50 mg at 13h, 7h, 1h before + diphenhydramine 50 mg 1h before). Metformin: hold day of contrast, resume 48h later if Cr stable.
RoundsRx Infographic Series · #51 · Respiratory · PDF 144 KB
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Famous Cases
Landmark clinical cases that shaped modern medicine. Diagnose historical figures from their symptoms.
8 CASES
Medical History
Famous Cases in Medicine
Landmark clinical cases that shaped modern medicine. Each case is presented as a clinical scenario, try to guess the diagnosis before revealing the answer.
Case 1 · 1809–1865
Genetics · Cardiology
A 6-foot-4-inch statesman towers over his era, with disproportionately long limbs, large hands and feet, lax joints, and a thin, asymmetric face. He is famously melancholic and chronically constipated. He is assassinated at 56, so no one ever learns what his vasculature would have done with another decade.
Clinical Question: What connective tissue disorder does this habitus suggest, and what alternative syndrome must be considered when a marfanoid body comes with mucosal nodules?
Abraham Lincoln, The Marfan vs MEN2B Debate
Marfan syndrome was proposed in 1962, after a distant relative sharing an ancestor was diagnosed with it. The rival theory is MEN2B (multiple endocrine neoplasia type 2B): marfanoid habitus plus mucosal neuromas plus medullary thyroid carcinoma, argued from photographs showing bumpy lips and his lifelong constipation (colonic ganglioneuromatosis). Neither is proven; DNA testing of his relics has been debated for decades. Teaching points: the marfanoid-habitus differential is Marfan, MEN2B, homocystinuria, and Loeys-Dietz, and the distinction matters because each has a different fatal complication to get ahead of: aortic root dissection surveillance in Marfan, prophylactic thyroidectomy in MEN2B (medullary thyroid cancer arrives in childhood, screen with calcitonin and RET testing), and thrombosis prevention in homocystinuria.
Alexander Gardner portrait, November 1863 (public domain)
Case 2 · 1799
Airway · Critical Care
A 67-year-old retired general rides his estate for hours in snow and freezing rain. The next evening he develops a severe sore throat; by 2 AM he has a muffled voice, drooling, and can barely swallow or breathe. Over the next 21 hours his physicians bleed him four times, removing an estimated 40% of his blood volume, and apply blistering agents. A junior physician urges an emergency tracheotomy and is overruled by his seniors. The patient dies that night, sitting upright to breathe.
Clinical Question: What airway diagnosis best fits this presentation, and what would modern management have looked like?
George Washington, Acute Bacterial Epiglottitis
The retrospective consensus is acute bacterial epiglottitis: the classic adult picture is the 4 D's: dysphagia, drooling, distress, and dysphonia (the muffled "hot potato" voice), with rapid progression and upright posturing to keep the airway open. Modern management is airway first: secure it early and gently in a controlled setting, because agitation can convert a narrowed airway into a complete obstruction, then IV antibiotics covering H. influenzae, streptococci, and staphylococci (ceftriaxone plus vancomycin). The two teaching tragedies: the bloodletting added severe iatrogenic hypovolemia to a septic, airway-obstructed patient, and the one physician with the right answer, the tracheotomy, was the most junior in the room. Hierarchy that silences a correct junior voice is still a patient-safety theme today.
Portrait by Gilbert Stuart (public domain)
Case 3 · 1947–1963
Endocrinology
A young politician with a history of chronic back pain, fatigue, and GI complaints develops progressive skin hyperpigmentation, hypotension, and weight loss. Labs reveal hyponatremia and hyperkalemia. He is started on daily cortisone replacement and DOCA pellet implants, which he will take for the rest of his life. His medical records are kept strictly confidential due to the political implications of a chronic illness diagnosis.
Clinical Question: What endocrine disorder does this presentation suggest, and what is the classic electrolyte pattern?
John F. Kennedy, Addison's Disease (Primary Adrenal Insufficiency)
JFK had autoimmune primary adrenal insufficiency characterized by cortisol and aldosterone deficiency. The classic electrolyte pattern is hyponatremia + hyperkalemia (from aldosterone deficiency). Hyperpigmentation occurs due to elevated ACTH stimulating melanocyte receptors. His case illustrates how adrenal crisis can be precipitated by physiologic stress, during his presidency, he required stress-dose steroids during multiple medical crises. His treatment regimen included hydrocortisone and fludrocortisone.
White House portrait, Cecil Stoughton, 1963 (public domain)
Case 4 · 1821
Oncology · GI
A 51-year-old exiled military leader on a remote island develops progressive epigastric pain, nausea, and anorexia over 18 months. He loses significant weight despite initially being overweight. His father died of a "pyloric obstruction." On autopsy, a large ulcerated mass is found at the pylorus with extension to adjacent lymph nodes. Modern hair analysis reveals arsenic levels 38× normal, raising debate about poisoning versus environmental exposure.
Clinical Question: What is the most likely diagnosis, and what hereditary cancer syndrome might this family history suggest?
Napoleon Bonaparte, Gastric Adenocarcinoma
Autopsy confirmed gastric adenocarcinoma at the pylorus. The family history (father, grandfather, and three sisters also died of stomach cancer) raises suspicion for hereditary diffuse gastric cancer (HDGC), associated with CDH1 mutations. The arsenic finding is likely from environmental exposure (green wallpaper containing copper arsenate was common in the era). Teaching points: alarm features for gastric cancer (weight loss, early satiety, progressive dyspepsia >55), family history red flags, and when to suspect hereditary cancer syndromes.
Portrait by Jacques-Louis David, 1812 (public domain)
Case 5 · 1921
Neurology · Infectious Disease
A 39-year-old politician vacationing at a Canadian island develops fever, malaise, and progressive ascending symmetric weakness over 3 days after swimming in cold water. He develops urinary retention and bilateral lower extremity paralysis. Sensory exam is notable for facial pain and leg dysesthesias. CSF shows mild pleocytosis. He never regains the ability to walk independently. The diagnosis at the time was poliomyelitis, but a 2003 retrospective analysis argued for an alternative diagnosis.
Clinical Question: What are the two leading diagnoses, and what clinical features help distinguish them?
Franklin D. Roosevelt, Poliomyelitis vs. Guillain-Barré Syndrome
FDR was diagnosed with poliomyelitis, but a 2003 Bayesian analysis (Goldman et al.) argued Guillain-Barré syndrome was 8× more likely given his age (39, rare for polio), symmetric descending-to-ascending paralysis, facial pain, dysesthesias, and prolonged fever. Polio favors: asymmetric weakness, no sensory involvement, younger patients. GBS favors: symmetric ascending paralysis, sensory symptoms, areflexia, albuminocytologic dissociation. Teaching point: this case is a classic board question on distinguishing acute flaccid paralysis, always compare the pattern of weakness, sensory findings, and CSF profile.
1944 portrait. Photo: Leon Perskie, CC BY 2.0
Case 6 · 1984
Neurology
A 42-year-old retired heavyweight boxing champion, three years after his final fight, develops a progressively soft voice, slowed movements, a masked face, and a resting tremor. His gait has lost its famous quickness. Cognition is largely intact. His symptoms respond to dopaminergic therapy, and he lives 32 more years with slowly progressive disease.
Clinical Question: What movement disorder is this, and does his occupation change the diagnosis?
Muhammad Ali, Parkinson's Disease vs Post-Traumatic Parkinsonism
He was diagnosed with Parkinson's disease at 42: the cardinal features are bradykinesia plus rest tremor and/or rigidity, and a clear levodopa response supports idiopathic PD. The permanent debate is whether thousands of head blows caused or accelerated it: chronic traumatic encephalopathy (CTE, dementia pugilistica) is a tauopathy that can include parkinsonism, but it is only confirmed at autopsy. Teaching points: parkinsonism has a differential (drug-induced from antipsychotics and metoclopramide, vascular, PSP and MSA, post-traumatic); young-onset parkinsonism (under 40) demands a Wilson's disease workup (ceruloplasmin, slit-lamp for Kayser-Fleischer rings) because it is treatable; and repetitive head injury is a dose-dependent neurodegeneration risk, which is why return-to-play concussion rules exist.
1967 press photograph, New York World-Telegram (public domain)
Case 7 · 1963–2018
Neurology
A 21-year-old physics graduate student becomes clumsy, falls without explanation, and develops slurred speech. Exam shows a striking mix: brisk reflexes and spasticity in the same limbs that show wasting and fasciculations, with completely normal sensation. He is given roughly two years to live. He survives 55 more, producing his most important work from a wheelchair and, later, a speech synthesizer.
Clinical Question: What is the diagnosis, what two motor systems does it destroy, and why was this course so unusual?
Stephen Hawking, Amyotrophic Lateral Sclerosis
ALS (Lou Gehrig disease, after the Yankees first baseman it killed in 1941) is defined by combined upper motor neuron signs (spasticity, hyperreflexia) and lower motor neuron signs (wasting, fasciculations) without sensory loss. Median survival is 3 to 5 years, usually from respiratory failure. Hawking's 55-year course is among the longest ever recorded: young-onset disease can progress slowly, though his was exceptional even for that. Exclude the treatable mimics before accepting the diagnosis: cervical myelopathy, multifocal motor neuropathy (responds to IVIG), and thyroid disease. What actually changes outcomes: non-invasive ventilation extends survival and quality of life, multidisciplinary clinic care, and early nutrition support (PEG); riluzole adds months, not years.
NASA/StarChild photograph (public domain)
Case 8 · 1888–1890
Psychiatry · Neurology
A 35-year-old painter suffers episodic attacks of confusion, hallucinations, and agitation, separated by lucid intervals of ferocious productivity. During one crisis he cuts off part of his left ear and presents it to a stranger. Asylum physicians diagnose "epilepsy" and reportedly treat him with digitalis. He drinks absinthe heavily and works with lead-based paints. At 37 he dies of a self-inflicted gunshot wound.
Clinical Question: What is the differential for episodic neuropsychiatric attacks with lucid intervals, and which classic drug toxicity turns vision yellow?
Vincent van Gogh, The Great Retrospective Differential
No single diagnosis is proven, which is exactly the teaching value. Leading candidates: temporal lobe epilepsy with interictal psychosis (his own physicians' diagnosis), bipolar disorder (episodic crises with hyperproductive intervals), absinthe and alcohol use with withdrawal, acute intermittent porphyria, and lead exposure from paint. The workup his story teaches for episodic psychosis with lucid intervals: EEG, urine porphyrins, heavy metals, substance history, never just a psychiatric label. The board pearl: digitalis toxicity classically causes xanthopsia (yellow-tinted vision) and halos around lights, and some speculate this colored his late palette; treat significant toxicity with digoxin immune Fab. His death is also a permanent reminder that psychiatric illness in a productive, functional person still kills.
Self-portrait, 1887 (public domain)
Case 9 · 1827
Toxicology · Hepatology
A 56-year-old composer with a 30-year history of progressive bilateral sensorineural hearing loss, chronic diarrhea, and heavy alcohol use presents with abdominal distension, jaundice, and recurrent fever. He undergoes paracentesis four times in his final months. He dies of hepatic failure. Modern analysis of his hair reveals lead levels 100× above normal. Genomic sequencing of his hair (2023) confirms hepatitis B infection and multiple genetic risk variants for liver disease.
Clinical Question: What are the likely causes of his liver disease, and what is the differential for his hearing loss?
Ludwig van Beethoven, Multifactorial Liver Failure & Lead Poisoning
His death was caused by hepatorenal syndrome from decompensated cirrhosis. Contributing factors included alcohol use, hepatitis B infection (confirmed by 2023 DNA analysis), and chronic lead exposure (from adulterated wine, a common practice in 19th-century Europe). The hearing loss differential includes lead ototoxicity, otosclerosis, and autoimmune inner ear disease. Teaching points: multifactorial liver disease, lead toxicity (abdominal colic, neuropathy, hearing loss, nephropathy), and the importance of considering environmental exposures.
Portrait by Joseph Karl Stieler, 1820 (public domain)
Case 10 · 1934
Hematology · Occupational
A 66-year-old physicist, the only person with Nobel Prizes in two sciences, presents with months of fatigue, recurrent fevers, and pallor. Labs show pancytopenia with a low reticulocyte count. For over 30 years she has handled radioactive isotopes without shielding, carrying vials in her pockets and admiring their glow at night, and she ran mobile X-ray units through World War I. She dies within months.
Clinical Question: What marrow diagnosis explains this pancytopenia, and how do you distinguish it from its mimics?
Marie Curie, Radiation-Induced Aplastic Anemia
Cumulative ionizing radiation destroyed her hematopoietic stem cells: aplastic anemia. Marrow is among the most radiosensitive tissues in the body (with gut and gonads), which is why radiation workers carry dosimeters today. The pancytopenia workup her case anchors: reticulocyte count first (low means a production problem), then smear, B12/folate, and marrow biopsy, where an empty fatty marrow = aplastic anemia, a hypercellular dysplastic marrow = MDS, and blasts = leukemia. Modern treatment: HSCT for the young with a matched sibling donor; ATG plus cyclosporine plus eltrombopag for the rest. Her lab notebooks are still radioactive (radium-226, half-life 1,600 years) and are stored in lead, readable only after signing a waiver.
Photograph c. 1920 (public domain)
Case 11 · 1853–1884
Hematology · Genetics
A queen with no family history of bleeding has a son who bruises massively from trivial injury, suffers crippling joint bleeds, and dies at 30 of a brain hemorrhage after a minor fall. Two of her daughters are healthy but pass the same disease to their sons, seeding it through the royal houses of Russia, Spain, and Prussia, including the heir to the Russian throne.
Clinical Question: What inheritance pattern is this, and how was the specific factor deficiency finally identified?
Queen Victoria, Hemophilia B Carrier (The Royal Disease)
Classic X-linked recessive inheritance: carrier mothers are healthy, half their sons are affected, half their daughters carry, and there is never male-to-male transmission. With no affected ancestors, the mutation was almost certainly de novo in Victoria or her immediate parentage. In 2009, genetic analysis of the Romanov remains (her great-grandson Alexei) identified an F9 splice-site mutation: hemophilia B (factor IX deficiency). Teaching points: hemophilia A (factor VIII, about 80% of cases) and B are clinically identical, with hemarthroses, deep muscle bleeds, and a prolonged aPTT with a normal PT; factor assays make the distinction because treatment is factor-specific. Alexei's bleeding, and Rasputin's sway over his desperate parents, is a case study in how untreatable illness breeds medical charlatans.
Photograph by Alexander Bassano, 1882 (public domain)
Case 12 · 1977–1981
Dermatology · Oncology
A 32-year-old Jamaican musician notices a dark streak under his right great toenail after a soccer injury. He attributes it to the injury. A biopsy eventually reveals malignant melanoma. He declines amputation of the toe due to religious beliefs (Rastafari), opting for excision of the nail bed only. Four years later he presents with metastatic disease to the lungs, liver, and brain. He dies at age 36.
Clinical Question: What subtype of melanoma is most common in dark-skinned individuals, and what is the ABCDE rule modification for subungual lesions?
Bob Marley, Acral Lentiginous Melanoma
Acral lentiginous melanoma (ALM) is the most common melanoma subtype in African American, Hispanic, and Asian patients. It occurs on palms, soles, and nail beds, areas often missed on routine skin exams. For subungual melanoma, use the ABCDEF rule: Age (peak 50–70), Band (brown-black, breadth >3mm), Change (rapid growth), Digit (thumb/great toe most common), Extension (Hutchinson sign, pigment extending to nail fold), Family history. His case highlights the critical importance of examining acral sites in all skin types and not dismissing nail pigmentation as traumatic.
Zurich concert, 1980. Photo: Ueli Frey, CC BY-SA 3.0
Case 13 · 1788–1820
Hematology · Psychiatry
A monarch in his 50s develops recurrent episodes of severe abdominal pain, constipation, tachycardia, and limb weakness. During acute episodes he becomes confused, agitated, and frankly psychotic, speaking rapidly for hours and exhibiting paranoid delusions. His physicians note his urine is dark, described as "port wine colored." He suffers at least 5 major episodes over 30 years, each lasting weeks to months.
Clinical Question: What metabolic disorder explains the combination of neurovisceral symptoms and dark urine?
King George III, Acute Intermittent Porphyria
The leading retrospective diagnosis is acute intermittent porphyria (AIP), a defect in porphobilinogen deaminase causing accumulation of ALA and PBG. The classic triad is abdominal pain + neuropsychiatric symptoms + autonomic dysfunction. Port-wine urine results from porphobilinogen oxidizing to porphobilin on standing. Attacks are triggered by fasting, medications, and stress. This case is a board-favorite for teaching the porphyrias and the differential of acute abdominal pain + psychiatric symptoms.
Coronation portrait by Allan Ramsay, 1762 (public domain)
Case 14 · 1906–1938
Infectious Disease · Ethics
A healthy 37-year-old cook has never had a serious illness, yet typhoid fever outbreaks follow her from household to household across New York. An investigator links her to outbreak after outbreak; her stool grows Salmonella Typhi. She refuses gallbladder surgery, is quarantined, released on a promise not to cook, and is found five years later cooking at a maternity hospital under an assumed name after an outbreak there kills two people. She spends 26 years in quarantine.
Clinical Question: How does a person with no symptoms transmit typhoid for decades, and how is chronic carriage managed today?
Mary Mallon (Typhoid Mary), Chronic S. Typhi Carriage
Salmonella Typhi establishes chronic biliary carriage: it colonizes the gallbladder, forming biofilm on gallstones, and sheds in stool for years while the host feels well. About 2 to 5% of infected patients become chronic carriers, more with gallstones, and as a cook she delivered it directly into food. Modern management: prolonged fluoroquinolone therapy (about 4 weeks) clears most carriers; cholecystectomy for those with stones who fail antibiotics. The clinical typhoid refresher her name carries: stepwise fever with relative bradycardia (Faget sign), rose spots, and week-3 ileal perforation risk; treat with ceftriaxone or azithromycin, minding XDR strains. Her 26-year island quarantine remains the classic ethics case balancing individual liberty against public protection, argued again during every modern epidemic.
Mary Mallon (foreground), Riverside Hospital, 1909 (public domain)
Case 15 · 1951
Oncology · Ethics
A 31-year-old African American woman presents with vaginal bleeding. Biopsy reveals an aggressive cervical carcinoma. Despite radiation therapy, she dies 8 months later. Cells taken from her tumor, without her knowledge or consent, prove to be uniquely immortal in culture, doubling every 20–24 hours. They become the most widely used human cell line in biomedical research.
Clinical Question: What cell line was derived from this patient, and what ethical issues does it highlight?
Henrietta Lacks, HeLa Cells & Informed Consent
HeLa cells (from Henrietta Lacks) were the first immortalized human cell line. They have been used in polio vaccine development, cancer research, HIV/AIDS studies, and COVID-19 research, contributing to over 75,000 publications. Her case is the landmark example of informed consent failures in medical research. It directly influenced the development of modern bioethics guidelines including the Common Rule and Belmont Report.
Statue of Henrietta Lacks by Helen Wilson-Roe, Bristol (no verified free photograph of her exists). Photo: 14GTR, CC BY-SA 4.0
Case 16 · 1848
Neurology
A 25-year-old railroad foreman survives a 3-foot, 7-inch iron rod blasting through his left frontal lobe during a blasting accident. He walks and talks within minutes. In the months that follow, his colleagues report he is "no longer Gage", previously reliable and respectful, he becomes impulsive, profane, and unable to follow through on plans.
Clinical Question: What neuroanatomical structure was damaged, and what syndrome does this localize to?
Phineas Gage, Frontal Lobe Syndrome
The rod destroyed the left prefrontal cortex, specifically the orbitofrontal and ventromedial regions. This case provided the first clinical evidence that the frontal lobes mediate personality, executive function, and social behavior. It remains foundational in neuroscience, used to teach frontal lobe localization, the distinction between "preserved intelligence" and impaired judgment, and the concept of acquired sociopathy.
Daguerreotype of Gage holding the iron that injured him. Photo: Jack & Beverly Wilgus, CC BY-SA 3.0
16 cases · Updated August 2026 · More cases coming soon
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Sepsis · DKA · ARDS · Heart Failure · Antibiotics · ECG · Code Blue · Calculators
EmergentICU
Massive Transfusion Protocol
Hemorrhagic shock requiring rapid blood product replacement. 1:1:1 ratio (pRBC:FFP:platelets). Activate MTP early -do not wait for labs. Permissive hypotension until surgical control.
🔍 Overview
Definition & Triggers
Massive transfusion = replacement of ≥ 1 entire blood volume (≈ 10 units pRBC) in 24 hours, OR ≥ 4 units pRBC in 1 hour with ongoing hemorrhage. Activate MTP when anticipating need for massive resuscitation. See the MTP Activation Criteria table below for specific scoring systems (ABC Score, Shock Index) that trigger MTP activation.
During MTP
Vitals q5–15 min
Ionized Ca²⁺ q30 min -replace aggressively
Temperature -warm all products, forced air warming blanket
Urine output -Foley, target ≥ 0.5 mL/kg/hr
ABG/lactate q30–60 min (trend as resuscitation marker)
Restore perfusion with blood products (not crystalloid). Limit NS (hyperchloremic acidosis). Bicarbonate is not routine here: the acidosis is a perfusion problem, and bicarb generates CO₂ that worsens intracellular acidosis unless minute ventilation can rise to blow it off. Reserve it for pH < 7.1 with shock refractory to blood and pressors, purely to buy time until surgical or IR source control
Communicate with blood bank to deactivate MTP and return unused products
Do not deactivate prematurely. Ensure surgical source control is definitive before stopping MTP. Rebound coagulopathy can occur 4–6h post-resuscitation.
🚨 Management
1:1:1 Resuscitation
Based on PROPPR, 2015 -balanced ratio resuscitation. Goal: approximate whole blood composition. Know the nuance if asked: PROPPR's primary mortality endpoints (24h and 30-day) were not significantly different. What changed practice were the secondary outcomes, fewer exsanguination deaths and faster hemostasis with 1:1:1, in a trial widely regarded as underpowered for mortality.
Product
Ratio
Key Notes
pRBCs
1
O-neg until type & screen available (O-pos acceptable for males)
FFP
1
Replaces clotting factors. Thaw takes 20–30 min -keep thawed plasma available
Platelets
1
1 apheresis unit per 6-pack pRBC
Cryoprecipitate
Give when fibrinogen < 150
10 units = ↑ fibrinogen ~70 mg/dL
Adjuncts
Tranexamic Acid (TXA) 1g IV over 10 min → 1g over 8h -give within 3 hours of injury (CRASH-2, 2010)
Calcium: Replace aggressively -citrate in blood products chelates calcium → hypocalcemia → cardiac arrest. Give Calcium Chloride 1g IV per 4 units pRBC
Viscoelastic hemostatic assays provide point-of-care coagulation assessment in ~15–30 min, enabling goal-directed transfusion.
TEG Parameter
ROTEM Equivalent
What It Measures
Abnormal → Treatment
R time
CT (clotting time)
Time to initial fibrin formation (factor activity)
Prolonged → FFP
K time / Alpha angle
CFT / Alpha angle
Speed of clot strengthening (fibrinogen)
Prolonged K / low alpha → Cryoprecipitate
MA (max amplitude)
MCF (max clot firmness)
Clot strength (platelet + fibrinogen)
Low MA → Platelets (if fibrinogen adequate)
LY30
ML (max lysis)
Fibrinolysis at 30 min
LY30 > 3% → TXA (hyperfibrinolysis)
Clinical Pearl: TEG/ROTEM allows goal-directed transfusion, give the right product instead of empiric 1:1:1. Most useful once initial resuscitation is underway.
Calcium Replacement Protocol
Product
Dose
Route
Notes
Calcium Chloride
1g (10 mL of 10%) per 4 units pRBC
Central line preferred
3x more elemental Ca than gluconate. Extravasation causes tissue necrosis
Calcium Gluconate
3g IV per 4 units pRBC
Peripheral or central
Safer peripherally. Requires hepatic metabolism to release ionized Ca
Citrate Toxicity Signs: iCa < 1.0 mmol/L → perioral tingling, tremors, prolonged QT. iCa < 0.7 → hypotension, decreased cardiac output, cardiac arrest. Check iCa q30 min during active MTP.
TXA Timing (CRASH-2, 2010): Give TXA within 3 hours of bleeding onset. After 3 hours, TXA may increase mortality. Also effective in postpartum hemorrhage (WOMAN, 2017).
Whole Blood (LTOWB), Increasingly First-Line
Low-titer group O whole blood (LTOWB) has re-emerged as the preferred initial resuscitation product at most US Level I trauma centers and military settings (per AAST/ACS 2024 trauma resuscitation update). Each unit contains pRBCs, plasma, and platelets in physiologic ratio: no math, no thaw, no waste, automatic 1:1:1 by design.
Advantages: single product = balanced resuscitation, faster delivery (no thaw delay), reduced donor exposure (one donor instead of three), fewer bags/lines.
Practical use: first 4–6 units in massive hemorrhage, then transition to component therapy if more is needed (LTOWB inventory is limited).
Limitations: not universally available, "low-titer" anti-A and anti-B titers required to give safely to non-O recipients, shorter shelf life (~21 days vs 42 for pRBC).
Evidence: retrospective and observational studies show mortality benefit; large RCTs ongoing. Reduced 24h and 30-day mortality vs component therapy in trauma cohorts.
TBI Changes the Rules of MTP
If suspected or confirmed traumatic brain injury, the standard MTP targets shift. Hypotension worsens secondary brain injury, and an expanding intracranial hematoma is far harder to control than extracranial bleeding.
Target MAP ≥ 80 (or SBP ≥ 110 for adults). NO permissive hypotension. Why: cerebral perfusion pressure (CPP = MAP − ICP) drops with hypotension; even brief SBP < 90 doubles TBI mortality.
INR target < 1.4 (vs < 1.5 standard). Why: lower threshold for bleeding tolerance in a closed cranium.
Platelets > 100K (vs > 50K standard).
Hypertonic saline (3% bolus 250 mL or 23.4% bolus 30 mL) for ICP control. Why: NS volume contributes to brain edema; hypertonic saline shifts free water out of cells and buys time before definitive surgical decompression.
Reverse antiplatelets in surgical TBI with platelet transfusion + DDAVP, despite the PATCH 2016 caveat (which was for spontaneous ICH not requiring surgery, not for surgical TBI).
Reverse anticoagulants emergently, see Anticoagulation Reversal table below.
Hyperkalemia from Stored Blood
Stored RBCs leak K⁺ as they age. A unit at storage day 35 can have supernatant K⁺ of 30–40 mEq/L (vs < 5 mEq/L in fresh blood). At 4–6 units/hour during active MTP, this can drive serum K⁺ to dangerous levels rapidly, especially in:
Bilateral infiltrates, looks like ARDS, no cardiomegaly
Bilateral infiltrates with cardiomegaly, Kerley B lines, pleural effusions
Echo
Preserved EF, no chamber enlargement
Systolic or diastolic dysfunction, dilated chambers
Treatment
Stop transfusion. Supportive ARDS care: lung-protective ventilation, conservative fluids. Diuretics not helpful (and harmful if hypotensive). Corticosteroids unproven.
Stop transfusion. Diuretics (furosemide 20–40 mg IV). Sit patient up. Slow transfusion rate; smaller aliquots (250 mL increments).
Mortality
~5–10% in MTP setting; some studies up to 20%
Lower (~1–2%), more amenable to volume removal
Single most useful discriminator: BNP + echo. TRALI has normal BNP and preserved EF; TACO has elevated BNP and volume overload. If unsure, treat as TACO first (diuresis is reversible if wrong; ARDS-style restriction in true TACO worsens it). Report any suspected TRALI to the blood bank, the implicated donor needs to be excluded from future donation pools.
Anticoagulation Reversal in MTP
Most modern bleeding-MTP patients are on a DOAC, antiplatelet, or warfarin. Reversal is time-critical, especially in intracranial bleeding and surgical hemorrhage where the anticoagulant is dictating ongoing blood product needs.
Anticoagulant
Reversal Agent
Dose
Notes
Apixaban (Eliquis), rivaroxaban (Xarelto)
Andexanet alfa (Andexxa)
Low-dose: 400 mg bolus + 4 mg/min × 120 min. High-dose: 800 mg bolus + 8 mg/min × 120 min (if last dose > 5 mg apixaban or > 10 mg rivaroxaban within 8h)
Specific factor Xa decoy. Expensive (~$50,000/dose). Increased thromboembolism post-reversal, balance against benefit. ANNEXA-4 / ANNEXA-I
Dabigatran (Pradaxa)
Idarucizumab (Praxbind)
5 g IV (two 2.5 g vials) over 5–10 min
Specific Fab fragment. Rapid (< 5 min onset). Re-elevation of dabigatran possible at 12–24h, can re-dose. REVERSE-AD, 2017
Warfarin (Coumadin)
4-factor PCC (Kcentra) + vitamin K
4F-PCC: 25–50 units/kg IV (INR-based; max 5000 units). Vitamin K: 10 mg IV over 30 min
4F-PCC for emergent reversal (faster than FFP, lower volume, better outcomes). Vitamin K for sustained reversal (4F-PCC is short-acting, INR rebounds without K). Sarode, 2013
UFH (heparin)
Protamine sulfate
1 mg IV per 100 units of heparin given in last 2–3h (max 50 mg). Slow IV push over 10 min.
Watch for anaphylaxis (especially fish allergy, prior protamine, NPH insulin users), hypotension, paradoxical anticoagulant effect at high doses.
LMWH (enoxaparin)
Protamine sulfate (partial reversal only)
1 mg per 1 mg enoxaparin if given within 8h (~60% efficacy). 0.5 mg per 1 mg enoxaparin if 8–12h.
Only ~60% reversal at best (protamine binds anti-IIa activity but only partially anti-Xa). Andexanet has been studied but is NOT FDA approved for LMWH.
Platelets: 1 apheresis unit (or 6-pack random donor). DDAVP: 0.3 mcg/kg IV (max 20 mcg).
Controversial in spontaneous ICH (PATCH, 2016 showed harm in non-surgical ICH), but standard practice in MTP and emergent neurosurgery. DDAVP releases vWF and improves platelet adhesion.
Fondaparinux
No specific reversal
4F-PCC 50 units/kg or rFVIIa 90 mcg/kg as last resort
Off-label, mixed evidence. No FDA-approved specific reversal exists. Half-life 17–21h; supportive care often required.
🧪 Workup
Labs During MTP
CBC q30–60 min
PT/INR, PTT, fibrinogen q30–60 min
BMP (Ca²⁺, K⁺ -hyperkalemia from stored blood)
ABG/VBG (pH, lactate, base deficit)
TEG/ROTEM if available (point-of-care coagulation)
Type & screen / crossmatch
Monitor ionized calcium closely. Hypocalcemia from citrate toxicity is the #1 preventable cause of cardiac arrest during MTP.
💊 Medications
Drug
Dose
Indication
Tranexamic Acid (TXA)
1g IV bolus → 1g over 8h
Antifibrinolytic -give within 3h of injury
Calcium Chloride
1g IV per 4 units pRBC
Prevent/treat citrate-induced hypocalcemia
Calcium Gluconate
3g IV (equivalent to 1g CaCl)
Alternative if no central line (less tissue necrosis)
Cryoprecipitate
10 units IV
Fibrinogen < 150 mg/dL
Vitamin K (Phytonadione)
10 mg IV
If on warfarin or INR > 1.5
📋 On Rounds
Pimp Questions
What is the "lethal triad" in trauma?
Hypothermia + acidosis + coagulopathy. These three form a vicious cycle: hypothermia impairs coagulation cascade enzymes, acidosis inhibits clotting factor function, and coagulopathy leads to ongoing hemorrhage → more hypothermia and acidosis. Damage control resuscitation targets all three: warm products, limit crystalloid (worsens acidosis/dilutional coagulopathy), balanced 1:1:1 ratio.
Why do we give calcium during MTP?
Stored blood products contain citrate as anticoagulant. Citrate chelates ionized calcium. During rapid transfusion, citrate overwhelms hepatic metabolism → hypocalcemia → prolonged QT, hypotension, decreased cardiac output, cardiac arrest. Give 1g CaCl per 4 units pRBC. Monitor iCa q30 min.
When should TXA be given and what is the evidence?
Within 3 hours of injury onset. CRASH-2 trial (2010): TXA reduced all-cause mortality in bleeding trauma patients (14.5% vs 16%). Given > 3 hours it may increase mortality. Mechanism: inhibits plasminogen → plasmin conversion, reducing fibrinolysis.
What blood type do you give when there is no time for type and screen?
O-negative for females of childbearing age (prevents Rh sensitization). O-positive acceptable for males and post-menopausal females. Switch to type-specific blood once type & screen results available (~15–45 min).
What does a low MA on TEG indicate, and how do you treat it?
MA (maximum amplitude) reflects clot strength: platelet function (80%) and fibrinogen (20%). Low MA = platelet deficiency or low fibrinogen. Check fibrinogen first: if < 150, give cryoprecipitate. If adequate, give platelets.
Why do we limit crystalloid in hemorrhagic shock?
Excessive crystalloid causes dilutional coagulopathy, hypothermia, and hyperchloremic acidosis (if NS). Also causes tissue edema (ARDS, abdominal compartment syndrome). Crystalloid does not carry oxygen or replace clotting factors. Damage control resuscitation favors blood products.
What is permissive hypotension and when is it contraindicated?
Target SBP 80–90 until surgical hemostasis. Aggressive resuscitation before source control dislodges forming clots and worsens bleeding. Contraindicated in TBI, target MAP ≥ 80 to maintain cerebral perfusion.
Assessment: Massive upper GI bleed with baseline coagulopathy. Shock Index 1.6.
Management:
MTP activated. Two large-bore IVs. O-neg pRBC started
1:1:1 ratio. Cryo 10u immediately (fibrinogen 88)
CaCl 1g after 4 units. iCa monitored q30 min
Octreotide 50mcg bolus then 50mcg/hr + pantoprazole 80mg then 8mg/hr
Ceftriaxone 1g IV (SBP prophylaxis in cirrhosis + GI bleed)
Emergent EGD: Variceal bleed → band ligation, hemostasis achieved
MTP deactivated after 6u pRBC. Lactate trending down
Key lesson: Cirrhotic patients need aggressive fibrinogen replacement. Transfuse to Hgb 7–8 (overtransfusion ↑ portal pressure). Early endoscopy is critical.
📋 Case 3, Postpartum Hemorrhage
Patient: 32F, G3P3, vaginal delivery 45 min ago. EBL 2L, ongoing. HR 138, BP 74/42, AMS. Boggy uterus.
Assessment: PPH from uterine atony. Hemorrhagic shock. Shock Index 1.9.
Management:
MTP activated. O-neg pRBC (female of childbearing age)
Uterotonics + Bakri balloon → hemostasis. If refractory: IR embolization or hysterectomy
Stable at 2h. MTP deactivated
Key lesson: PPH is #1 cause of maternal death. Uterotonics first (atony is #1 cause). TXA early (WOMAN trial). Young patients compensate until sudden collapse.
During MTP
Vitals q5–15 min
Ionized Ca²⁺ q30 min -replace aggressively
Temperature -warm all products, forced air warming blanket
Urine output -Foley, target ≥ 0.5 mL/kg/hr
ABG/lactate q30–60 min (trend as resuscitation marker)
CBC, coags, fibrinogen q30–60 min
K⁺ -hyperkalemia from stored blood lysis
⚡ Summary
Activate Early, Not After the Labs
Trigger on physiology and mechanism, not on a hemoglobin. The classic definitions, 10 units in 24 h or 4 units in 1 h, are retrospective; ABC score 2 or more, a shock index above 1, or ongoing visible bleeding with hemodynamic instability activate it prospectively.The first hemoglobin in acute hemorrhage is falsely reassuring because the patient has not had time to hemodilute.
Give Balanced Ratios
1:1:1 plasma to platelets to red cells, which approximates whole blood. PROPPR compared 1:1:1 with 1:1:2 and its primary 24-hour and 30-day mortality endpoints were negative; the benefits, less death from exsanguination at 24 h and more achieved hemostasis, were secondary. Whole blood (low-titer group O) is increasingly used first line where available and simplifies the logistics.
Do Not Resuscitate With Crystalloid
Crystalloid dilutes clotting factors, worsens acidosis, drives hypothermia and pops formed clot.Give blood, not saline, and limit crystalloid to the minimum needed to carry drugs.
Permissive Hypotension Until Surgical Control
Target a systolic around 80 to 90 mmHg, or a palpable radial pulse, until bleeding is controlled, because a normal pressure blows off soft clot. Traumatic brain injury changes the rule: those patients need a normal or slightly raised pressure to preserve cerebral perfusion, so hypotension is not permissive when the head is injured.
Break the Lethal Triad
Hypothermia, acidosis and coagulopathy reinforce each other and drive mortality.Warm everything, the patient, the fluids and the room, because clotting enzymes fail below 34°C and no amount of product compensates. Correct the acidosis by stopping the bleeding and restoring perfusion, not with bicarbonate.
Give TXA Inside 3 Hours
Tranexamic acid 1 g IV over 10 min, then 1 g over 8 h, reduces mortality in trauma (CRASH-2). The 3-hour window is not a formality: given later it increases death from bleeding. In traumatic brain injury the benefit is greatest when it is given within the first hour (CRASH-3).
Replace Calcium Deliberately
Citrate in stored blood chelates calcium, and the resulting hypocalcemia causes hypotension, arrhythmia and coagulopathy, since calcium is factor IV. Check ionized calcium after every 4 units and replace; do not wait for the level in a patient who is receiving product fast. Also watch potassium, which rises with older units and is a real arrest risk in rapid transfusion.
Deactivate Only After Definitive Control
Stop when bleeding is surgically controlled, the patient is hemodynamically stable and lactate is clearing.Rebound coagulopathy occurs 4 to 6 h after resuscitation, so continue labs after deactivation. Use TEG or ROTEM where available to direct which product is actually needed rather than continuing fixed ratios, and reverse anticoagulants specifically: 4-factor PCC for warfarin and factor Xa inhibitors, idarucizumab for dabigatran.
Irreversible cessation of all brain function including brainstem. Standardized evaluation required. Two clinical exams by qualified physicians separated by observation period. Apnea test is the key confirmatory component.
🔍 Overview
Definition
Brain death = irreversible loss of all functions of the entire brain, including brainstem. Legal death in all US states. Requires systematic evaluation to exclude confounders.
Prerequisites (Must Meet ALL)
Prerequisite
Details
Known cause
Established etiology sufficient to cause brain death (e.g., massive stroke, TBI, anoxic injury)
Irreversibility
No possibility of recovery -adequate time for observation
No confounders
Core temp ≥ 36°C, SBP ≥ 100, no CNS depressants (check drug levels), no neuromuscular blockade, no severe metabolic derangements
Common Etiologies Leading to Brain Death
Etiology
Frequency
Key Features
Traumatic brain injury
~40%
MVA, falls, assaults. Often young patients. CT: diffuse axonal injury, herniation
Hemorrhagic stroke
~25%
Massive ICH, SAH with rebleed. CT: large hematoma with midline shift, herniation
Anoxic brain injury
~20%
Cardiac arrest, drowning, strangulation. CT: diffuse edema, loss of gray-white differentiation
Ischemic stroke
~10%
Large territory (MCA/basilar). CT: massive hemispheric or posterior fossa infarct with edema
Other
~5%
CNS infection, tumor, fulminant hepatic failure with cerebral edema
AAN 2023 Guideline: Greer et al, Neurology 2023 Minimum observation period before testing: 24 hours for anoxic brain injury (longer than structural causes). This is because anoxic injury can have delayed recovery. Structural causes (TBI, massive stroke) may be tested sooner if prerequisites are met.
Who Can Perform Brain Death Evaluation?
Attending physician with experience in brain death determination (varies by state law and hospital policy)
Typically: neurologist, neurosurgeon, or intensivist
The physician performing the evaluation should NOT be part of the transplant team (conflict of interest) Uniform Determination of Death Act, 1981
Two separate exams recommended (2010 AAN); 2023 guidelines state one exam by one qualified physician is sufficient in adults
🚨 Management
Clinical Examination (Two Required)
Brainstem Reflex
Test
Expected in Brain Death
Pupillary
Bright light in each eye
Fixed, dilated (4–9 mm), no response
Corneal
Cotton wisp or saline drops
No blink
Oculocephalic
Doll's eyes (turn head side to side)
No eye movement (eyes stay midline)
Oculovestibular
Cold caloric (50 mL ice water in ear canal)
No eye deviation toward cold ear
Gag
Stimulate posterior pharynx
No response
Cough
Suction catheter to carina
No cough
Apnea Test
Pre-oxygenate with 100% FiO₂ × 10 min
Obtain baseline ABG (PaCO₂ should be 35–45)
Disconnect ventilator, deliver O₂ via T-piece at 6 L/min
Observe 8–10 minutes for any respiratory effort
Repeat ABG -positive test: PaCO₂ ≥ 60 OR ↑ ≥ 20 from baseline with NO respiratory effort
Abort if SBP < 90, SpO₂ < 85%, or cardiac arrhythmia
Apnea test safety: This is the most physiologically dangerous part of the evaluation. Monitor continuously. Have vasopressors drawn up. Abort immediately for SBP <90, SpO2 <85%, or cardiac arrhythmia. A failed apnea test does NOT mean the patient is not brain dead - proceed to ancillary testing.
Documentation Checklist
Item
Document
Etiology
Confirmed cause sufficient to explain brain death
Prerequisites
Temp >= 36C, SBP >= 100, no drugs, no NMB, no metabolic derangement
Clinical exam
All brainstem reflexes absent: pupillary, corneal, oculocephalic, oculovestibular, gag, cough. No motor response
Apnea test
Baseline PaCO2, duration off vent, final PaCO2, no respiratory effort observed
Ancillary test
Type, result, if applicable
Time of death
Exact time second exam completed (or ancillary test confirmed)
Examiner(s)
Name, credentials, not part of transplant team
Family Communication
Explain brain death = legal death. The patient has died. This is not a coma, not a vegetative state, not "life support keeping them alive." The brain has irreversibly ceased functioning.
Separate the brain death conversation from the organ donation conversation. Allow time for the family to process.
OPO (Organ Procurement Organization) must be notified of ALL deaths and imminent deaths - this is a legal requirement, not a clinical decision CMS CoP, 42 CFR 482.45
The family does NOT have the legal right to refuse brain death determination (it is a medical diagnosis), though some states have religious exemptions (NJ, NY)
Religious and cultural considerations: New Jersey has a legal exemption allowing families to reject brain death on religious grounds. New York requires "reasonable accommodation" of religious beliefs. California requires "reasonably brief" accommodation. Hospital ethics and legal teams should be involved in disputed cases. Lewis et al, Neurocrit Care 2016
🧪 Workup
Required Studies
CT/MRI showing devastating brain injury
Core temperature ≥ 36°C
Drug screen / levels (barbiturates, benzos, opioids, neuromuscular blockers)
BMP -no severe electrolyte/metabolic derangements
ABG -before and after apnea test
Ancillary Tests (if clinical exam cannot be completed)
Test
Finding in Brain Death
Cerebral angiography
No intracerebral blood flow (gold standard)
EEG
Electrocerebral silence × 30 min
Nuclear scan (HMPAO)
"Hollow skull" -no cerebral uptake
Transcranial Doppler
Reverberating flow or absent diastolic flow
Ancillary Test Comparison
Test
Sensitivity
Specificity
Advantages
Disadvantages
4-vessel angiography
~100%
~100%
Gold standard. Definitive
Invasive, contrast, requires angiography suite
Tc-99m HMPAO scan
94%
100%
Portable, non-invasive, "hollow skull" sign is definitive
May have false negatives with very early testing
EEG
90%
~90%
Widely available, bedside, non-invasive
Artifact-prone in ICU. Electrical silence does not assess posterior fossa/brainstem
Transcranial Doppler
89%
99%
Bedside, repeatable, non-invasive
Operator-dependent. 10% of patients have inadequate acoustic windows
CTA
85-95%
Variable
Fast, widely available
Not yet universally accepted. Criteria still evolving. Frampas et al, Radiology 2009
Key principle: Ancillary tests supplement, not replace, clinical judgment. A positive ancillary test in the absence of proper prerequisites is insufficient for brain death declaration. Always ensure confounders are excluded regardless of ancillary test results.
💊 Medications
No medications are used for brain death evaluation per se. Key considerations:
Confirm absence of CNS depressants -must have drug levels below therapeutic range. Wait 5 half-lives for barbiturates, benzodiazepines, paralytics
Vasopressors -maintain SBP ≥ 100 during evaluation (organ perfusion if donation candidate)
Desmopressin (DDAVP) 1–4 mcg IV -for diabetes insipidus (common with brain death -loss of ADH from posterior pituitary)
Levothyroxine (Synthroid) -T4 replacement if organ donation planned
Methylprednisolone (Solu-Medrol) -stress-dose steroids if organ donation planned
📋 On Rounds
Pimp Questions
What confounders must be excluded before brain death testing?
Hypothermia (core temp must be ≥ 36°C), hypotension (SBP must be ≥ 100), CNS depressants (barbiturates, benzos, opioids -check levels), neuromuscular blockade (confirm train-of-four), and severe metabolic derangements (electrolyte abnormalities, hepatic/uremic encephalopathy). Each of these can mimic brain death and must be corrected or excluded.
What defines a positive apnea test?
After disconnecting the ventilator for 8–10 min with O₂ insufflation: PaCO₂ ≥ 60 mmHg OR rise ≥ 20 mmHg from baseline with NO respiratory effort observed. This confirms the brainstem has no CO₂-driven respiratory drive. Abort if hemodynamic instability or desaturation.
Why is diabetes insipidus common in brain death?
The posterior pituitary loses function → no ADH (vasopressin) secretion → massive free water diuresis. Presents as polyuria (> 300 mL/hr), hypernatremia, low urine specific gravity (< 1.005). Treat with DDAVP 1–4 mcg IV. Important for organ preservation.
What is the legal time of death in brain death?
The legal time of death is the time the second clinical examination is completed (or the time the ancillary test confirms absent brain function, if used in lieu of a clinical exam). This is NOT the time the ventilator is discontinued or the time the heart stops. Family should be informed that the patient is legally dead at that moment, even though the heart may still be beating on life support. Wijdicks et al, Neurology 2010
Can spinal reflexes be present in brain death?
Yes. Spinal reflexes are mediated at the spinal cord level, NOT the brainstem. They do NOT invalidate brain death. Common spinal reflexes seen: deep tendon reflexes, triple flexion response (leg withdrawal), Lazarus sign (arms flex and rise), plantar responses. These can be distressing to families and nursing staff - educate them that these are spinal automatisms, not signs of brain function. Saposnik et al, Neurology 2000
What are the 2023 AAN/AAP/CNS guideline changes for brain death determination?
Key updates from the 2023 AAN/AAP/CNS practice guideline: (1) One exam by one qualified physician is sufficient in adults (previously two exams recommended). (2) Minimum observation period: 24h for anoxic brain injury, shorter for structural causes. (3) Apnea test target PaCO2 raised to >=60 mmHg (unchanged). (4) Ancillary testing acceptable if clinical exam cannot be completed. (5) Standardized checklist recommended for documentation. Greer et al, Neurology 2023
When do you need ancillary testing instead of clinical exam?
Ancillary tests are needed when the clinical exam cannot be reliably completed: (1) Severe facial trauma preventing cranial nerve testing. (2) Pre-existing pupil abnormalities. (3) High cervical spine injury (cannot perform apnea test safely). (4) Chronic CO2 retention (apnea test unreliable). (5) Hemodynamic instability during apnea test requiring abort. (6) Residual drug levels that cannot be excluded as confounders. The gold standard ancillary test is 4-vessel cerebral angiography showing no intracranial flow.
What is the difference between brain death and persistent vegetative state?
Brain death = irreversible loss of ALL brain function including brainstem. No spontaneous respiration, no brainstem reflexes, no consciousness. Patient is legally dead. Persistent vegetative state (PVS) = intact brainstem but destroyed cerebral cortex. Patient has sleep-wake cycles, may open eyes, has brainstem reflexes, breathes independently, but has no awareness or purposeful behavior. PVS patients are NOT dead - they require ongoing care decisions about life-sustaining treatment.
What organ donor management goals should be initiated after brain death declaration?
Contact the organ procurement organization (OPO) early - legally required. Donor management targets: (1) MAP 60-110 mmHg (vasopressors OK). (2) UOP 0.5-3 mL/kg/hr. (3) PaO2 >300 on 100% FiO2 (lung assessment). (4) Na <155 (DDAVP for DI). (5) T4/T3 replacement for hemodynamic support. (6) Methylprednisolone 15 mg/kg for organ protection. (7) Correct coagulopathy, acidosis, hypothermia. Malinoski et al, Crit Care Med 2012
Clinical Examples
📋 Case 1 - Brain Death After Massive ICH
Patient: 62M found unresponsive. CT head: massive right hemispheric ICH with midline shift, uncal herniation, and complete effacement of basal cisterns. GCS 3. Intubated in ED.
Hospital day 1: Neurosurgery: non-surgical given size and herniation. Fixed dilated pupils bilaterally. No cough/gag. No overbreathing the ventilator. No sedation given in 24h. Urine output 800 mL/hr with SG 1.001 (DI developing).
Prerequisites checked: Core temp 36.8C, SBP 105 (on vasopressin), drug screen negative, BMP normal, no paralytics (train-of-four 4/4).
Clinical exam #1 (attending neurologist): Pupils fixed 7mm bilaterally. Absent corneal, oculocephalic, oculovestibular (cold calorics), gag, and cough reflexes. No motor response to central pain.
Apnea test: Pre-oxygenated 10 min. Baseline PaCO2 38. Disconnected vent with O2 insufflation at 6 L/min x 8 min. No respiratory effort. Repeat ABG: PaCO2 72 (rise of 34). Positive apnea test.
Outcome: Brain death declared. OPO contacted. Family meeting held. Patient became organ donor (liver, kidneys, heart). Time of death = time of exam completion.
📋 Case 2 - Confounders Requiring Ancillary Testing
Patient: 28F found unresponsive after polysubstance overdose (barbiturates + benzodiazepines). Anoxic brain injury from prolonged respiratory arrest before EMS arrival. CT: diffuse cerebral edema with loss of gray-white differentiation.
Problem: Drug levels still positive for phenobarbital (therapeutic elimination takes 5+ half-lives = several days). Cannot reliably perform clinical exam with CNS depressants on board.
Approach: Waited 72h. Repeat phenobarbital level still 15 mcg/mL. Decision made to proceed with ancillary testing rather than waiting additional days.
Ancillary test: Tc-99m HMPAO cerebral perfusion scan: "hollow skull phenomenon" - no intracranial uptake. Consistent with absence of cerebral blood flow.
Outcome: Brain death declared based on clinical findings + ancillary test. Family counseled that drug levels were a confounder to clinical testing but the absence of cerebral blood flow is definitive.
📋 Case 3 - Aborted Apnea Test, Completed with EEG
Patient: 55M with massive basilar artery stroke. Fixed dilated pupils, absent brainstem reflexes on clinical exam. Prerequisites met.
Apnea test attempt: After disconnecting ventilator, patient became hemodynamically unstable at 4 minutes (BP 62/38, HR 35). Apnea test aborted per protocol (SBP < 90). No respiratory effort was observed during the 4 minutes.
Problem: Cannot complete the apnea test. PaCO2 only reached 52 (did not reach 60 threshold). Clinical exam alone is insufficient without a complete apnea test.
Ancillary test: EEG performed: electrocerebral silence (no electrical activity) over 30 minutes of recording, meeting technical standards (minimum 8 scalp electrodes, interelectrode impedances 100-10,000 ohms, sensitivity 2 mcV/mm).
Outcome: Brain death declared based on clinical exam + EEG confirming electrocerebral silence. This approach is endorsed when the apnea test cannot be safely completed.
⚡ Summary
What It Means
Irreversible cessation of all brain function including the brainstem.It is death, legally and clinically, not a very deep coma or a prognosis, and the vocabulary used with families should reflect that. The evaluation exists to prove irreversibility beyond doubt before that declaration is made.
Every Prerequisite Must Be Met First
A known, irreversible catastrophic brain injury on imaging; core temperature above 36°C; systolic pressure above 100 mmHg; no confounding drug effect, paralytic or severe metabolic or endocrine derangement.Any unmet prerequisite invalidates the whole examination, so this is the step that gets checked twice. Send a drug screen and account for the clearance of sedatives, especially with renal or hepatic failure or after therapeutic hypothermia.
Wait Long Enough, and Longer After Anoxia
The AAN 2023 guideline requires a minimum 24-hour observation period after anoxic brain injury, longer than for structural causes, because anoxic injury can show delayed recovery. Extend it further after targeted temperature management, since hypothermia prolongs drug clearance.
The Clinical Examination
Coma with no response to noxious stimulus, and absent brainstem reflexes at every level: pupillary, corneal, oculocephalic, oculovestibular (cold caloric), gag and cough. Spinal reflexes and the Lazarus sign can persist and do not indicate brain function, which is worth explaining to the family before they witness one. Two examinations by qualified physicians, per institutional policy.
The Apnea Test Is the Confirmatory Piece
Preoxygenate, disconnect from the ventilator with apneic oxygenation, and observe for respiratory effort.A positive test is no respiratory effort with PaCO₂ at or above 60 mmHg, or 20 mmHg above baseline, on a documented arterial blood gas. A gas is required: observation without one does not count.
It Is Also the Most Dangerous Step
Monitor continuously with vasopressors drawn up.Abort immediately for systolic below 90, saturation below 85%, or arrhythmia.An aborted apnea test is not a failed test: it means the test is inconclusive and an ancillary study is needed instead.
Use Ancillary Tests Only When the Exam Cannot Be Completed
Cerebral angiography, nuclear perfusion scan, transcranial Doppler or EEG, for high cervical injury, severe facial trauma, an inability to complete the apnea test, or unresolvable drug confounding. They supplement, they do not replace, the clinical examination, and each has its own false-positive and false-negative profile.
Documentation, Family and the Legal Variation
Time of death is the time the second examination or the confirmatory ancillary study is completed, and the documentation must record every prerequisite, both examinations, the apnea test with its blood gas, and the examiners. Notify the organ procurement organization before approaching the family, and keep the donation conversation separate from the declaration. Jurisdiction matters: New Jersey allows a religious exemption, and New York and California require reasonable accommodation of religious objection, so know local law and policy before you begin.
Pericardial effusion → intrapericardial pressure exceeds chamber filling pressure → impaired diastolic filling → ↓ cardiac output → obstructive shock. Rate of accumulation matters more than volume -acute 150 mL can cause tamponade; chronic effusions may accumulate 1–2 L before symptoms.
Etiology
Category
Causes
Malignancy
Lung, breast, lymphoma, melanoma -most common cause of large effusions
Infection
Viral (Coxsackie, Echo), TB (especially in endemic areas), bacterial, fungal
Pericardiocentesis -echo-guided, subxiphoid approach. Aspirate even 20–30 mL can dramatically improve hemodynamics
Pericardial drain -leave catheter if recurrent/malignant effusion
Pericardial window -surgical option for recurrent tamponade
Do NOT give positive pressure ventilation to tamponade patients if avoidable. PPV ↓ venous return → immediate cardiovascular collapse. Avoid intubation until pericardiocentesis is imminent or underway.
One principle, two phenomena. The LV and RV share a septum and sit inside a fixed pericardial space. Anything that overloads the RV mechanically displaces the LV, dropping LV filling, stroke volume, and BP. Pulsus paradoxus is the dynamic / beat-to-beat version (RV transiently outgrowing the LV during each inspiration). Reverse Bernheim is the static / chronic version (a continuously dilated RV pushing the septum into the LV). Same plumbing, different time scale.
Pulsus Paradoxus
Definition: an exaggerated drop in systolic BP during inspiration of > 10 mmHg (normal drop is ≤ 10).
Beat-to-beat physiology: inspiration → more negative intrathoracic pressure → ↑ venous return → RV transiently dilates → in a constrained space the septum bows leftward → LV stroke volume drops → systolic BP drops > 10 mmHg.
Two buckets of causes. Anything that exaggerates the inspiratory drop in LV stroke volume produces pulsus. Two mechanisms get you there:
1. Reduced cardiac filling / restricted chamber expansion - the heart sits in a box that can't enlarge, so the inspiratory RV-LV competition for space is amplified.
Cardiac tamponade(~75-98%, pooled ~82%) - canonical setting. Magnitude tracks hemodynamic severity; disappears after pericardiocentesis. More sensitive than Beck's triad.
Restrictive cardiomyopathy(< 20%) - reported but uncommon.
Constrictive pericarditis(< 20%, often absent) - the rigid pericardium blocks transmission of inspiratory pressure swings to the LV, so pulsus is classically blunted or absent here. Kussmaul sign (rising JVP on inspiration) is the more typical finding.
Massive pulmonary embolism(uncommon; described in case reports, rare in series) - the dilated RV constrains LV expansion (the dynamic face of reverse Bernheim, below). Physiology is sound, but pulsus is not a reliable bedside finding in PE.
2. Exaggerated negative intrathoracic pressure - the patient generates such large inspiratory swings that even an unconstrained heart can't keep LV stroke volume steady.
Severe asthma / status asthmaticus(~50% have pulsus > 10 mmHg in acute attacks; ~25-40% have > 20 mmHg in severe attacks) - air-trapping + huge inspiratory effort against obstruction. Pulsus > 25 mmHg correlates with FEV₁ < 40% predicted; falling pulsus = improvement.
Severe COPD exacerbation(less prominent than asthma, no firm %) - same mechanism, but high baseline RA pressure blunts the inspiratory swing.
Upper airway obstruction(variable; no firm data) - croup, severe laryngospasm, foreign body.
Falsely absent pulsus despite tamponade physiology: severe AR (retrograde LV filling masks the drop), ASD (right-to-left equalization), elevated LV diastolic pressure, severe pulmonary HTN (impaired transmission of RV volume changes), extreme hypovolemia, and positive-pressure ventilation (inverts the physiology). A normal pulsus does not rule out tamponade in any of these.
Reverse pulsus paradoxus - systolic BP rises with inspiration. Seen in HOCM, positive-pressure ventilation in tamponade, and isorhythmic AV dissociation. Mostly a board concept.
How to measure (manual): inflate BP cuff above systolic. Slowly deflate. First Korotkoff sound heard only in expiration = Phase 1 pressure. Continue deflating until sound is heard throughout the cycle = Phase 2 pressure. Pulsus paradoxus = Phase 1 − Phase 2. > 10 mmHg = positive. On an arterial line, just measure the inspiratory-to-expiratory systolic variation directly.
Reverse Bernheim Effect
A pressure- or volume-overloaded RV bows the interventricular septum leftward into the LV, shrinking the LV cavity, dropping preload, and dropping stroke volume. Patients can be in shock with a structurally normal LV. This is the static / chronic counterpart to pulsus paradoxus - same ventricular-interdependence physics, but continuous rather than beat-to-beat. (The "forward" Bernheim, LV pushing into RV, is largely historical; the reverse form is alive and well in critical care.)
Massive pulmonary embolism - the prototype. Acute RV pressure overload → septal bowing → LV underfilling → shock. This is why aggressive fluid loading in Category E PE can be catastrophic: more volume into a dilated RV worsens septal bowing and drops CO further. Guideline approach: modest 500 mL crystalloid trial, then norepinephrine ± dobutamine if no response.
Acute RV infarction - same mechanism with an infarcted, dilated RV.
Severe pulmonary HTN / cor pulmonale - chronic version; explains low CO despite preserved LV function.
High PEEP / positive-pressure ventilation - raises RV afterload; reverse Bernheim contributes to the BP drop after intubation in marginal patients.
Tamponade and constrictive pericarditis - pericardial constraint amplifies interdependence; reverse Bernheim is part of why LV filling fails here too.
Echo signature: the "D-sign." The LV in short-axis loses its circular shape and looks like a D because the septum has flattened leftward. End-systolic D = RV pressure overload (PE, pulmonary HTN). End-diastolic D = RV volume overload (severe TR, ASD).
Pericardiocentesis Technique Overview
Step
Details
Positioning
Patient semi-upright (30–45°) to pool fluid inferiorly
Approach
Subxiphoid (most common), apical, or parasternal, echo-guided preferred
Needle
18G spinal needle, advance toward left shoulder at 30° angle to skin
Confirmation
Aspiration of fluid; agitated saline echo contrast confirms intrapericardial position
Drainage
Place pigtail catheter for ongoing drainage if >100 mL or expected reaccumulation
Key point: Even 20–50 mL aspiration can produce dramatic hemodynamic improvement because the pericardial pressure-volume curve is steep once the pericardium is non-compliant.
💊 Medications
Tamponade is a mechanical problem requiring mechanical solution (drainage). No medications fix tamponade.
Intervention
Details
IV NS bolus
500–1000 mL -bridge to pericardiocentesis
Phenylephrine (Neo-Synephrine)
If hypotensive -maintain SVR as bridge. 100–200 mcg IV boluses
Why is positive pressure ventilation dangerous in tamponade?
PPV increases intrathoracic pressure → decreases venous return to the right heart. In tamponade, cardiac output is already critically preload-dependent. Removing venous return → immediate cardiovascular collapse. If intubation is necessary, prepare for hemodynamic crash and have pericardiocentesis ready.
What is pulsus paradoxus and why does it occur?
SBP drop > 10 mmHg with inspiration. Normally, inspiration increases RV filling and slightly decreases LV filling. In tamponade, the rigid pericardium constrains total cardiac volume -inspiratory RV expansion occurs at the expense of LV compression (ventricular interdependence). This exaggerates the normal drop in SBP.
What echo findings suggest tamponade?
(1) RA collapse in systole (most sensitive early sign), (2) RV diastolic collapse (more specific), (3) IVC plethora (dilated, no respiratory variation), (4) > 25% respiratory variation in mitral inflow velocities. A large effusion without these findings = effusion without tamponade.
How does the rate of fluid accumulation affect tamponade physiology?
Rate matters more than volume. Acute accumulation of 150–200 mL (e.g., trauma, iatrogenic) can cause tamponade because the pericardium has no time to stretch. Chronic effusions (e.g., malignancy, hypothyroidism) can accumulate 1–2 L before causing hemodynamic compromise because the pericardium gradually distends. This is why post-procedural tamponade is so dangerous, small volumes cause rapid decompensation.
What is electrical alternans and what causes it?
Beat-to-beat alternation in QRS amplitude (and sometimes axis) on ECG. Caused by the heart literally swinging back and forth within a large pericardial effusion. Highly specific (~95%) for tamponade but not sensitive (~20%). When present with low voltage and sinus tachycardia, strongly suggests large effusion with tamponade physiology.
When is pulsus paradoxus ABSENT despite tamponade?
Pulsus paradoxus may be absent in: (1) Severe aortic regurgitation (maintains LV filling regardless of respiration), (2) Atrial septal defect (equalizes atrial pressures), (3) Loculated effusion compressing only one chamber (common post-surgical), (4) Positive pressure ventilation (reverses respiratory mechanics). Also unreliable in severe hypotension where SBP is too low to detect variation.
What is the most common cause of large pericardial effusion causing tamponade?
Malignancy, lung cancer, breast cancer, and lymphoma are the top three. Malignant effusions are often hemorrhagic and tend to reaccumulate rapidly after drainage. In the developing world, tuberculosis is the leading cause. Idiopathic/viral is the most common cause of pericarditis, but malignancy leads for large effusions causing tamponade.
How do you differentiate tamponade from constrictive pericarditis?
Both impair diastolic filling, but the mechanism differs. Tamponade: fluid compresses chambers, impaired filling throughout diastole, pulsus paradoxus present, Kussmaul sign absent, equalization of diastolic pressures.
Clinical Examples
📋 Case 1, Malignant Pericardial Effusion
Patient: 58F with metastatic breast cancer presenting with 2 weeks of progressive dyspnea, orthopnea, and chest pressure.
Labs: BUN 148, Cr 11.2, K 6.1. ECG: diffuse ST elevation (pericarditis pattern), low voltage.
Echo: Moderate-large effusion with early RA collapse. RV diastolic collapse not yet present.
Management:
IV fluids for hemodynamic support
Intensive daily hemodialysis, definitive treatment for uremic pericarditis
Heparin-free dialysis to avoid worsening hemorrhagic effusion
NSAIDs/colchicine have limited role in uremic pericarditis (unlike viral)
Pericardiocentesis reserved if hemodynamic deterioration occurs
Teaching point: Uremic pericarditis is an indication for emergent dialysis. The effusion is often hemorrhagic. Must use heparin-free dialysis to avoid worsening bleeding into the pericardium.
📋 Case 3, Post-MI Free Wall Rupture
Patient: 72M, day 4 post-anterior STEMI (LAD occlusion, delayed presentation). Sudden hemodynamic collapse with loss of consciousness.
Vitals: HR 130 (PEA on monitor), BP unobtainable.
Exam: Unresponsive, JVD, no heart sounds auscultated. EMD (electromechanical dissociation), electrical activity without pulse.
Bedside echo: Large pericardial effusion with echodense material (clot), RV collapse, no ventricular contraction visible.
Management:
CPR initiated, IV fluids wide open
Emergent pericardiocentesis attempted, aspiration of frank blood
Emergent CT surgery consulted for surgical repair of free wall rupture
Mortality >90%, most patients do not survive to the OR
Teaching point: Free wall rupture typically occurs 3–7 days post-MI when the necrotic myocardium is weakest. Risk factors: first MI, anterior wall, delayed reperfusion, elderly, female. PEA arrest post-MI = always consider tamponade from free wall rupture.
⚡ Summary
The Physiology in One Line
Pericardial fluid raises intrapericardial pressure above chamber filling pressure, so the ventricles cannot fill. This is obstructive shock. How fast the fluid accumulates matters more than how much there is: 150 mL arriving quickly can tamponade, while a liter accumulating slowly may not.
Beck's Triad Is Insensitive
Hypotension, raised JVP and muffled heart sounds are all present in only about 30% of cases. Tachycardia and a narrow pulse pressure are earlier. Do not wait for the complete triad, and do not use its absence to exclude tamponade: echocardiography is the diagnostic test.
What the Echo Shows
Right atrial systolic collapse (sensitive) and right ventricular diastolic collapse (specific), a plethoric inferior vena cava that does not collapse with inspiration, and exaggerated respiratory variation in mitral and tricuspid inflow. Tamponade is a clinical diagnosis supported by echo, not an echo finding alone.
Pulsus Paradoxus and Why It Happens
An inspiratory fall in systolic pressure of more than 10 mmHg. The ventricles share a septum inside a fixed pericardial space, so inspiratory filling of the right ventricle pushes the septum leftward and reduces left ventricular stroke volume. It can be falsely absent in severe aortic regurgitation, atrial septal defect, high left ventricular diastolic pressure, and severe pulmonary hypertension, so its absence does not rule tamponade out.
Definitive Treatment Is Drainage
Echo-guided pericardiocentesis is lifesaving and nothing else substitutes for it.A surgical window is preferred for a loculated or posterior effusion, for purulent pericarditis, and after trauma, where a needle will not achieve or maintain drainage.
Temporize With Volume, Never With Diuretics
Give IV fluid to raise filling pressure above pericardial pressure while drainage is being arranged. Diuretics and nitrates reduce preload and can precipitate arrest, which is the reverse of the instinct in a patient with a raised JVP.
Positive Pressure Ventilation Can Kill Them
Avoid intubation until pericardiocentesis is imminent or already underway. Positive pressure drops venous return in a patient whose cardiac output is entirely preload-dependent, and the collapse is immediate. If intubation is unavoidable, use ketamine, keep the patient volume-loaded and have the needle ready.
Find the Cause Once They Are Stable
Malignancy (lung, breast, lymphoma, melanoma) is the commonest cause of a large effusion. Also infection (viral, tuberculous, bacterial), uremia, post-myocardial infarction, aortic dissection rupturing into the pericardium, connective tissue disease, and post-cardiac surgery. Send the fluid for cytology, culture including mycobacteria, cell count and chemistry, and remember that a malignant effusion recurs, so it usually needs a window or a pericardial drain.
Mean PAP ≥ 20 mmHg at rest by right heart catheterization. WHO Group 1 (PAH) is the classic form. RV failure is the primary cause of death. Avoid volume overload and systemic vasodilators.
HFrEF, HFpEF, valvular disease -MOST COMMON cause of PH
3
Lung disease/hypoxia
COPD, ILD, OSA
4
CTEPH
Chronic thromboembolic PH -potentially curable with pulmonary endarterectomy
5
Multifactorial
Sarcoidosis, hematologic, metabolic
Group 2 (left heart disease) is the most common cause of PH. PAH-specific therapies are CONTRAINDICATED in Group 2 -they worsen pulmonary edema.
Hemodynamic Definitions (6th World Symposium, 2018)
Type
mPAP
PAWP
PVR
Groups
Pre-capillary PH
≥20 mmHg
≤15 mmHg
>2 WU
Groups 1, 3, 4, 5
Isolated post-capillary PH (IpcPH)
≥20 mmHg
>15 mmHg
≤2 WU
Group 2
Combined pre- and post-capillary PH (CpcPH)
≥20 mmHg
>15 mmHg
>2 WU
Group 2 (with vascular remodeling) or Group 5
Updated 2022 definition: PH is now defined as mPAP >20 mmHg (lowered from ≥25). PVR threshold for pre-capillary PH lowered from ≥3 WU to >2 WU. These changes identify patients earlier in disease progression.
Vasoreactivity Testing
Feature
Details
Who gets tested?
All patients with idiopathic, heritable, or drug-associated PAH (Group 1 only). NOT for Groups 2-5
Agents used
Inhaled nitric oxide (10-20 ppm) or IV epoprostenol or IV adenosine during RHC
Positive response
Reduction in mPAP ≥10 mmHg to reach absolute mPAP ≤40 mmHg with maintained or increased cardiac output
If positive (~10% of IPAH)
Trial of high-dose calcium channel blockers (nifedipine, diltiazem, or amlodipine). NOT verapamil (negative inotropy)
If negative
Initiate PAH-specific therapy based on risk stratification (ERA + PDE5i for most; add prostacyclin if high-risk)
Long-term CCB responders
Only ~5-7% of IPAH patients are true long-term CCB responders. Must reassess at 3-6 months
Right Heart Catheterization, Key Values to Interpret
Parameter
Normal
Abnormal (PH)
Clinical Significance
mPAP
<20 mmHg
≥20 mmHg
Defines PH. Correlates with disease severity
PAWP (PCWP)
6-12 mmHg
>15 = post-capillary
Distinguishes Group 1 (pre-capillary) from Group 2 (post-capillary)
PVR
<2 WU
>2 WU = pre-capillary component
Elevated PVR with high PAWP = combined pre/post-capillary (CpcPH)
Cardiac output/index
CI >2.5 L/min/m²
CI <2.0 = severe RV failure
Low CI is a strong predictor of mortality
RAP
0-5 mmHg
>14 = severe RV failure
Elevated RAP indicates RV failure and volume overload
SvO2
65-75%
<60% = inadequate CO
Low mixed venous sat reflects poor cardiac output
🚨 Management
General Principles
Treat underlying cause -Group 2: optimize HF. Group 3: supplemental O₂. Group 4: anticoagulation ± PTE
PAH-specific therapy -only for Group 1 (and select Group 4/5). Based on vasoreactivity testing
Avoid: excessive IV fluids (RV cannot handle volume), systemic vasodilators (worsen V/Q mismatch), high-dose diuretics (RV is preload-dependent)
Epoprostenol = most potent. Continuous IV infusion. Line infection risk. Never abruptly stop -rebound PH crisis.
sGC stimulator
Riociguat (Adempas)
For PAH or inoperable CTEPH. Contraindicated with PDE-5i.
Right Heart Failure Management (Acute Decompensation)
Volume management: RV is preload-sensitive BUT volume overload worsens RV dilation → septal bowing → LV impairment. Target gentle diuresis with IV furosemide. Avoid aggressive fluid boluses.
Vasopressors:Norepinephrine preferred (maintains systemic pressure without increasing PVR). Avoid phenylephrine (pure alpha = increases PVR). Consider vasopressin as adjunct.
Inotropes:Dobutamine or milrinone to augment RV contractility. Milrinone also reduces PVR (pulmonary vasodilator).
Pulmonary vasodilators: Inhaled NO or inhaled epoprostenol, reduce PVR without systemic hypotension. Avoid systemic vasodilators.
Avoid: Intubation if possible (positive pressure ventilation ↑ PVR → RV collapse). If needed, use low tidal volumes, avoid hypoxia/hypercarbia/acidosis.
Arrhythmia management: AF/flutter poorly tolerated in PH (loss of atrial kick devastating for stiff RV). Cardiovert early.
Intubating a PH patient can be fatal. Positive pressure ventilation increases RV afterload, and induction agents cause systemic hypotension → RV ischemia → cardiac arrest. If intubation is unavoidable: use ketamine (maintains SVR), push-dose epinephrine at bedside, and have inhaled NO/epoprostenol ready.
Vasoreactivity testing -inhaled NO or IV epoprostenol during RHC. + response → trial of CCB
PFTs -exclude Group 3
V/Q scan -exclude Group 4 (CTEPH)
CT chest -parenchymal lung disease
Labs: BNP/NT-proBNP, HIV, ANA, LFTs
6-minute walk distance -functional assessment
💊 Medications
Drug
Dose
Route
Key Notes
Sildenafil (Revatio)
20 mg TID
PO
First-line oral. Avoid nitrates.
Tadalafil (Adcirca)
40 mg daily
PO
Once daily dosing advantage
Ambrisentan (Letairis)
5–10 mg daily
PO
ERA. Monthly LFTs.
Epoprostenol (Flolan)
2–16 ng/kg/min
Continuous IV
Most potent. Never stop abruptly. Half-life 3–5 min.
Riociguat (Adempas)
0.5–2.5 mg TID
PO
For PAH or CTEPH. Do not combine with PDE-5i.
📋 On Rounds
Pimp Questions
Why are PAH-specific therapies contraindicated in Group 2 PH?
Group 2 PH is caused by elevated left-sided filling pressures. PAH-specific vasodilators (prostacyclins, ERAs, PDE-5i) dilate the pulmonary vasculature → increased flow into an already congested left heart → worsening pulmonary edema and flash pulmonary edema. Treat the underlying LV dysfunction instead.
What happens if you abruptly stop epoprostenol?
Rebound PH crisis and death. Epoprostenol has a half-life of only 3–5 minutes. Abrupt cessation → acute pulmonary vasoconstriction → acute RV failure → death within minutes to hours. Patients need continuous infusion via dedicated central line. Line complications (infection, occlusion) are medical emergencies.
How do you differentiate pre-capillary from post-capillary PH?
What defines a positive vasoreactivity test and who should get it?
Vasoreactivity testing is performed only in idiopathic, heritable, or drug-associated PAH (Group 1). NOT for other groups. Agents: inhaled NO, IV epoprostenol, or IV adenosine during RHC. Positive response: fall in mPAP ≥10 mmHg to absolute mPAP ≤40 mmHg with maintained or increased cardiac output. Only ~10% of IPAH patients are vasoreactive, and only ~5-7% are true long-term CCB responders.
Why is intubation dangerous in pulmonary hypertension?
Intubation in PH is extremely high-risk for several reasons: (1) Positive pressure ventilation increases RV afterload (increases intrathoracic pressure → compresses pulmonary vasculature). (2) Induction agents cause systemic hypotension → decreased RV coronary perfusion → RV ischemia. (3) Hypoxia, hypercarbia, and acidosis all increase PVR. The result is acute RV failure and PEA arrest.
How do you manage volume status in acute RV failure from PH?
The RV is preload-dependent but volume-intolerant. Excess volume → RV dilation → interventricular septum bows into LV → decreased LV filling → decreased cardiac output (ventricular interdependence). Management: gentle diuresis with IV furosemide (goal net negative 0.5-1L/day). Avoid aggressive fluid boluses. If hypotensive, use vasopressors (norepinephrine preferred) rather than fluids.
What is CTEPH and why is it important to diagnose?
Chronic thromboembolic pulmonary hypertension (CTEPH, Group 4) occurs when organized thrombus persists in pulmonary arteries after PE, causing mechanical obstruction + vascular remodeling. Incidence: 2-4% after acute PE. It is the only potentially curable form of PH. Screen with V/Q scan (NOT CT angiography, CTA can miss chronic disease). Treatment: pulmonary endarterectomy (PTE) at experienced centers is potentially curative.
What is the initial combination therapy approach for newly diagnosed PAH?
Based on AMBITION Trial, NEJM 2015, upfront dual combination therapy (ERA + PDE-5i) is now standard for most newly diagnosed PAH patients. The trial showed ambrisentan + tadalafil reduced clinical failure events by 50% compared to monotherapy. Risk stratification guides further escalation: low-risk patients may start with oral combination; intermediate/high-risk patients should receive triple therapy including parenteral prostacyclin.
Clinical Examples
📋 Case 1, Group 1 PAH Workup in Young Woman with Scleroderma
Patient: 38F with limited systemic sclerosis (CREST) presents with progressive exertional dyspnea over 6 months. Now WHO FC III (dyspnea with minimal activity). No orthopnea or PND. 6MWD: 310 meters (reduced). SpO2 drops to 88% with walking.
Workup:
TTE: RV dilation with moderate dysfunction, RVSP 68 mmHg, moderate TR, RA enlarged, TAPSE 14mm (reduced), small pericardial effusion. LV normal. No valvular disease.
Labs: BNP 480, ANA 1:640 (centromere pattern), anti-Scl-70 negative. HIV negative. Normal PFTs (no restrictive disease).
Vasoreactivity testing: Not performed (CTD-associated PAH, not idiopathic, vasoreactivity testing only for IPAH/heritable/drug-associated).
Assessment: Group 1 PAH (CTD-associated, scleroderma). Pre-capillary PH confirmed (mPAP 48, PAWP 12, PVR 8.5). High-risk features: WHO FC III, low CI, low SvO2, elevated RAP, pericardial effusion.
Management:
Upfront triple therapy: Ambrisentan 5mg PO daily + tadalafil 40mg PO daily + IV treprostinil (started in ICU, titrated up).
Supportive: Supplemental O2 to maintain SpO2 >90%, gentle diuresis for fluid overload, anticoagulation (patient-specific decision in CTD-PAH).
Follow-up: 3-month reassessment: 6MWD improved to 385m, BNP decreased to 180, WHO FC II. Continued current regimen.
Key lesson: Scleroderma-associated PAH requires systematic workup. RHC is mandatory for diagnosis. Vasoreactivity testing is NOT done for CTD-PAH. High-risk patients warrant upfront triple therapy including parenteral prostacyclin per AMBITION Trial, NEJM 2015 principles.
📋 Case 2, Group 2 PH from Left Heart Disease
Patient: 72M with HFpEF (EF 55%), HTN, DM2, BMI 38, and OSA presents with worsening exertional dyspnea and lower extremity edema. Referred for "pulmonary hypertension" after TTE showed elevated RVSP.
Workup:
TTE: EF 55%, grade II diastolic dysfunction (E/e' 18), LA dilated, RVSP 55 mmHg, mild RV dilation, moderate TR.
Treat the underlying cause: Aggressive diuresis (IV furosemide 40mg → net negative 1-1.5L/day), sodium restriction, CPAP for OSA.
HFpEF optimization: SGLT2 inhibitor started (EMPEROR-Preserved, NEJM 2021), MRA, BP control.
PAH-specific therapy:NOT initiated. PAH drugs (ERAs, PDE-5i, prostacyclins) are contraindicated in Group 2 PH, they increase pulmonary blood flow into an already volume-overloaded left heart → worsening pulmonary edema.
After optimization: Repeat TTE in 3 months showed RVSP decreased to 38 mmHg with euvolemia. RV function improved.
Key lesson: Always check PAWP before starting PAH therapies. Group 2 PH is treated by optimizing the underlying left heart disease, NOT with PAH-specific drugs. CpcPH (high PAWP + high PVR) is increasingly recognized but treatment remains focused on decongestion and LHD optimization.
📋 Case 3, Acute RV Failure from Pulmonary Hypertension
Patient: 45F with known idiopathic PAH on IV epoprostenol (via Hickman catheter), ambrisentan, and tadalafil. Presents with 3 days of worsening dyspnea, abdominal distension, and lower extremity edema. Found to have Hickman line exit site erythema. T 38.9°C, HR 120, BP 84/52, SpO2 85% on 4L NC.
Assessment: Acute RV failure from PAH, triggered by line infection (sepsis increases PVR) + possible subtherapeutic epoprostenol delivery (line dysfunction).
Management:
Critical: Do NOT stop epoprostenol. Verify pump function and line patency immediately. Increase epoprostenol dose by 2 ng/kg/min.
Hemodynamic support: Norepinephrine for MAP >65 (maintains coronary perfusion). Avoid fluid boluses, RV is already volume-overloaded.
Inhaled pulmonary vasodilator: Inhaled NO 20 ppm started via high-flow nasal cannula (reduce RV afterload without systemic hypotension).
Diuresis: Furosemide 80mg IV bolus then 20mg/hr drip (goal 1-2L net negative/day). Monitor urine output closely.
Infection: Vancomycin + cefepime empirically for line infection. IR consulted for line exchange over wire (cannot remove, need continuous epoprostenol access).
Avoid intubation: Managed with high-flow nasal cannula at 50L/min, FiO2 60%. SpO2 improved to 92%.
Outcome: Blood cultures grew MSSA. Antibiotics narrowed. RV function improved over 72h with diuresis and infection control. Hickman exchanged on day 4. Discharged on day 10 back to baseline.
Key lesson: Acute RV failure in PAH is a medical emergency. Identify and treat the trigger (infection, non-adherence, arrhythmia). NEVER stop epoprostenol. Avoid intubation and fluid boluses. Use norepinephrine (not phenylephrine) for systemic pressure, inhaled vasodilators for PVR reduction, and careful diuresis.
⚡ Summary
The Definition Changed in 2022
Mean pulmonary artery pressure above 20 mmHg at rest, lowered from 25.Pre-capillary PH also requires PVR above 2 Wood units (lowered from 3) with a wedge pressure of 15 or below.Right heart catheterization is required: echocardiography estimates and screens, it does not diagnose.
Classify Before You Treat
Group 1 PAH (idiopathic, heritable, connective tissue disease, HIV, portopulmonary, drugs). Group 2 left heart disease. Group 3 lung disease and hypoxia. Group 4 CTEPH. Group 5 multifactorial.The group determines the treatment completely, and getting it wrong is the central error in this topic.
Group 2 Is the Commonest and Must Not Get PAH Drugs
Left heart disease is the most frequent cause of pulmonary hypertension, and PAH-specific therapies are contraindicated in it. Vasodilating the pulmonary bed while the left atrium cannot accept the extra flow drives pulmonary edema. Treat the left heart instead. The wedge pressure is what separates the two, which is another reason the catheter is non-negotiable.
Always Rule Out CTEPH
Group 4 is potentially curable by pulmonary endarterectomy, so it must never be missed.The screening test is a V/Q scan, not CT angiography, because CTPA misses distal chronic organized thrombus. Every patient with unexplained pulmonary hypertension gets one.
Vasoreactivity Testing Is for Group 1 Only
A positive response, a fall in mPAP of at least 10 mmHg to below 40 with preserved cardiac output, identifies the roughly 10% who respond to high-dose calcium channel blockers.Giving calcium channel blockers to a non-responder causes systemic hypotension and right ventricular collapse, which is why the test comes first and is done at a PH center.
Group 1 Therapy Is Combination and Early
Three pathways: endothelin receptor antagonists, nitric oxide-cGMP agents (PDE5 inhibitors and riociguat), and prostacyclin agents.Upfront combination therapy beats sequential add-on (AMBITION). Parenteral prostacyclin for high-risk disease.Never combine a PDE5 inhibitor with riociguat: the hypotension is severe.
Right Ventricular Failure Is What Kills
Manage volume carefully in both directions.Overload distends the RV, worsens tricuspid regurgitation and bows the septum into the LV; over-diuresis drops the preload a stiff RV depends on. Avoid systemic vasodilators, which drop coronary perfusion to a pressure-overloaded RV. In decompensation, use norepinephrine to maintain systemic pressure above pulmonary pressure, add an inotrope such as dobutamine or milrinone, correct hypoxia and acidosis (both are pulmonary vasoconstrictors), and consider inhaled pulmonary vasodilators.
Intubation Can Be Fatal
Positive pressure raises RV afterload and induction agents drop systemic pressure, so the RV becomes ischemic and arrests on the table.Avoid intubation wherever possible. If it is unavoidable: ketamine for induction, a vasopressor running before the drugs go in, an experienced operator, and the lowest airway pressures that will do the job. Avoid Valsalva, and treat arrhythmias aggressively, since a stiff RV depends heavily on atrial contraction.
Predictable chest pain with exertion, relieved by rest or nitroglycerin. Atherosclerotic plaque causing fixed stenosis. Optimize with GDMT before revascularization. Lifestyle modification is foundation.
🔍 Overview
Definition
Stable angina = predictable, reproducible chest discomfort triggered by exertion or emotional stress, lasting 2–10 min, relieved by rest or sublingual nitroglycerin. Caused by fixed coronary stenosis limiting flow during increased demand.
Risk Stratification
Feature
Low Risk
High Risk
Stress test
No ischemia, good exercise capacity
Ischemia at low workload, ↓ EF with exercise, ≥ 2 mm ST depression
Based on ISCHEMIA, 2020 - no mortality benefit of routine revascularization over GDMT in stable CAD.
PCI - symptom relief only. No mortality benefit in stable CAD (COURAGE, 2007; ORBITA, 2018; REVIVED-BCIS2, 2022).
CABG - survival benefit in left main disease, 3-vessel disease with ↓ EF, or diabetes with multi-vessel disease (FREEDOM, 2012)
Bottom line: For stable CAD, GDMT is the foundation. Revascularization improves angina symptoms but does NOT reduce death or MI (ISCHEMIA, COURAGE, ORBITA). CABG has survival benefit only in left main, 3-vessel + reduced EF, or diabetes with multivessel disease (FREEDOM).
🧪 Workup
ECG - may be normal at rest. ST depression during pain.
Stress testing - exercise preferred. Pharmacologic if cannot exercise. Nuclear/echo for added anatomic info.
What did the ISCHEMIA trial show about revascularization in stable CAD?
No reduction in death or MI with routine invasive strategy vs conservative management in patients with stable CAD and moderate-severe ischemia. Invasive strategy improved anginal symptoms more. Key takeaway: GDMT is the foundation -revascularization is for symptom control in stable disease, not mortality reduction.
When does CABG provide a survival benefit over PCI?
Left main disease (≥ 50% stenosis), 3-vessel disease with reduced EF, and diabetes with multi-vessel disease (FREEDOM trial). CABG provides more complete revascularization with better long-term outcomes in these high-risk anatomies.
Why is a nitrate-free interval important?
Continuous nitrate exposure → nitrate tolerance within 24–48h via depletion of sulfhydryl groups needed for NO generation. A 10–14 hour nitrate-free interval (usually overnight) restores sensitivity. This is why isosorbide mononitrate is dosed once daily in the morning.
What is the mechanism of ranolazine?
Late sodium current inhibitor - reduces intracellular calcium overload without hemodynamic effects (no change in HR or BP). MERLIN-TIMI 36, 2007 showed reduced recurrent ischemia but no mortality benefit. Prolongs QTc - avoid with other QT-prolonging drugs.
What did the COURAGE trial show?
PCI + GDMT was not superior to GDMT alone for death or MI in stable CAD. Optimal medical therapy is the foundation of treatment. Revascularization improves symptoms but not hard outcomes. COURAGE, 2007.
Which patients benefit from CABG over PCI in diabetes?
FREEDOM, 2012: CABG superior to PCI for death, MI, and stroke in diabetics with multivessel disease. Lower rates of repeat revascularization with CABG. Drives current guideline recommendation for surgical revascularization in this population.
What is the Canadian Cardiovascular Society (CCS) angina classification?
Class I: ordinary activity doesn't cause angina (e.g., walking, climbing stairs). Class II: slight limitation - angina with rapid walking or climbing > 1 flight. Class III: marked limitation - angina walking 1-2 blocks or 1 flight. Class IV: angina at rest or with any physical activity.
When should you choose pharmacologic vs exercise stress testing?
Pharmacologic if patient cannot exercise (orthopedic limitation, deconditioning, PAD) or has uninterpretable ECG (LBBB, paced rhythm, LVH with repolarization changes, digoxin use). Exercise preferred when possible - provides functional capacity data and is more physiologic.
What is the role of coronary calcium scoring?
CAC = 0 has excellent negative predictive value for obstructive CAD. MESA study validated its use for risk reclassification. Helps reclassify intermediate-risk patients (moves them to low or high risk). Not useful if patient already has known CAD. Obtained via non-contrast CT chest.
Clinical Examples
📋 Case 1, New Diagnosis of Stable Angina
Patient: 64M with HTN, HLD, T2DM. Exertional chest pressure with brisk walking × 3 months, relieved by rest within 5 min. Normal ECG at rest. EF 60%.
Key findings: Classic stable angina: predictable exertional chest pain, relieved by rest. Intermediate pretest probability for CAD given age, sex, and risk factors.
Management:
Stress test for risk stratification, exercise stress echo (can exercise, interpretable ECG)
If high-risk stress test (large ischemic burden, drop in BP) → coronary angiography
Teaching point: Beta-blockers are first-line for stable angina, they reduce mortality in post-MI patients and improve anginal symptoms. CCBs (amlodipine, diltiazem) are second-line or added if beta-blockers insufficient.
📋 Case 2, Refractory Angina Despite Medical Therapy
Patient: 72F with known 3-vessel CAD (declined CABG 2 years ago). Angina now occurring with minimal exertion despite metoprolol 100 mg BID, amlodipine 10 mg, isosorbide mononitrate 60 mg daily, ASA, atorvastatin. CCS class III.
Key findings: Refractory angina on maximized triple anti-anginal therapy. Previously documented 3-vessel disease. Progressive limitation despite optimal medical management.
Management:
Add ranolazine 500 mg BID → titrate to 1000 mg BID (late sodium channel inhibitor, reduces ischemia without hemodynamic effects)
Heart team discussion: CABG vs high-risk PCI for 3-vessel disease ISCHEMIA, 2020
Cardiac rehab referral (improves exercise capacity and anginal threshold)
Ensure nitrate-free interval (10-14h overnight) to prevent tolerance
Teaching point: Ranolazine is the fourth-line anti-anginal agent, it works by a unique mechanism (late Na channel) and can be added to any combination without hemodynamic interactions. No mortality benefit, but improves symptoms.
📋 Case 3, Vasospastic (Prinzmetal) Angina
Patient: 42F non-smoker, no traditional risk factors. Recurrent rest angina at 3-4 AM with transient ST elevation on telemetry that resolves spontaneously. Normal coronary angiogram.
Key findings: Classic vasospastic angina: rest pain, early morning, transient ST elevation, clean coronaries. Often triggered by smoking, cocaine, or cold exposure.
Management:
Long-acting CCB first-line: amlodipine 5-10 mg daily or diltiazem ER 240 mg daily
Teaching point: Beta-blockers are contraindicated in vasospastic angina, they remove beta-2 vasodilation, leaving alpha-mediated constriction unopposed. This is the one form of angina where beta-blockers make things worse.
⚡ Summary
Define It Before You Test It
Predictable, exertional chest discomfort relieved by rest or nitroglycerin, from a fixed atherosclerotic stenosis. Any change in the pattern, at rest, more frequent, or at a lower threshold, is no longer stable angina and moves the patient onto the acute coronary syndrome pathway.
Medical Therapy Is the Foundation
Antiplatelet, high-intensity statin, blood pressure and diabetes control, plus a beta blocker as first-line antianginal. Add a calcium channel blocker or long-acting nitrate for persistent symptoms, and ranolazine when the heart rate or blood pressure will not tolerate more. The statin and antiplatelet are what change mortality; the antianginals only change how the patient feels.
The Result That Changed Practice
Revascularization improves angina but does not reduce death or myocardial infarction in stable CAD (ISCHEMIA, COURAGE, and ORBITA, where PCI did not beat a sham procedure for exercise time). So optimize medical therapy first, and offer PCI for symptoms that persist despite it, not as a reflex to an abnormal stress test.
When Revascularization Does Save Lives
CABG has a survival benefit in left main disease, three-vessel disease with reduced ejection fraction, and diabetes with multivessel disease (FREEDOM). Those are anatomic and physiologic indications, not symptomatic ones, which is why the anatomy still matters even in a patient whose angina is controlled.
Pick the Stress Test for the Patient
Can exercise with an interpretable ECG → exercise ECG, cheapest and first line. Uninterpretable ECG → add imaging with exercise echo or SPECT. Cannot exercise → pharmacologic. LBBB or a paced rhythm → vasodilator nuclear, not dobutamine, because septal motion artifact makes the echo uninterpretable. Low to intermediate risk needing anatomy → coronary CTA, which has a very high negative predictive value and rules CAD out.
Know What a High-Risk Stress Test Looks Like
Ischemia at a low workload, a fall in ejection fraction with exercise, ST depression of 2 mm or more, or a large ischemic territory. These, along with left main or three-vessel anatomy and CCS class III to IV symptoms despite medical therapy, are what push toward catheterization rather than another medication.
Lifestyle Is Not the Soft Part of the Plan
Smoking cessation is the single highest-yield intervention and reduces events more than any drug on the list. Add exercise, a Mediterranean-style diet, weight loss, and cardiac rehabilitation, which independently improves survival.
Common Pitfalls
Do not stress-test an asymptomatic patient: it finds lesions whose treatment does not help and starts a cascade. Do not treat a stenosis found on angiography without functional significance, which is what FFR or iFR is for. Do not stop the statin because the LDL looks good: the benefit is from continued treatment, not from a number reached once.
Crohn disease (transmural, skip lesions, any GI segment) vs Ulcerative Colitis (mucosal, continuous, colon only). Distinguish from infectious colitis. Biologics have transformed management.
🔍 Overview
Crohn Disease vs Ulcerative Colitis
Feature
Crohn Disease
Ulcerative Colitis
Location
Mouth to anus (terminal ileum most common)
Colon only -rectum always involved, extends proximally
Depth
Transmural → fistulas, strictures, abscesses
Mucosa/submucosa only
Pattern
Skip lesions, cobblestoning
Continuous, no skip lesions
Histology
Non-caseating granulomas
Crypt abscesses, pseudopolyps
Bloody diarrhea
Less common
Hallmark symptom
Smoking
Worsens disease
Protective (but don't recommend!)
Surgery
Not curative -disease recurs
Total colectomy is curative
Toxic megacolon (colon dilation > 6 cm + systemic toxicity) is a life-threatening complication of both CD and UC. Requires surgical consultation, broad-spectrum antibiotics, and possible colectomy.
Severity Scoring, Truelove and Witts (UC)
Parameter
Mild
Moderate
Severe
Bloody stools/day
< 4
4–6
> 6
Heart rate
Normal
≤ 90
> 90
Temperature
Normal
≤ 37.8°C
> 37.8°C
Hemoglobin
Normal
≥ 10.5 g/dL
< 10.5 g/dL
ESR
≤ 20
20–30
> 30
Clinical Pearl: Truelove and Witts criteria are used at the bedside to determine if a UC flare requires IV steroids (severe) vs outpatient management (mild). A patient meeting severe criteria needs admission for IV methylprednisolone and GI consultation.
Crohn Disease Activity Index (CDAI), Concept
The CDAI is a composite score (0–600+) incorporating stool frequency, abdominal pain severity, general well-being, extraintestinal features, anti-diarrheal use, abdominal mass, hematocrit, and body weight. CDAI < 150 = remission; 150–220 = mild; 220–450 = moderate; > 450 = severe. Primarily used in clinical trials. At the bedside, use clinical judgment: stool frequency, CRP, nutritional status, and presence of complications (fistula, abscess) guide management decisions.
Mnemonic, B Symptoms of IBD Flare Requiring Admission
"FAST", Fever, Anemia, Six+ stools/day, Tachycardia. Any patient meeting these criteria should be admitted for IV steroids and GI consultation. Always rule out C. diff and CMV colitis before escalating immunosuppression.
🚨 Management
Step-Up Therapy
Severity
UC Treatment
Crohn Treatment
Mild
Mesalamine (Asacol/Lialda) PO/PR
Mesalamine (limited evidence) or budesonide
Moderate
Oral steroids → thiopurines or biologics
Budesonide (Entocort) → thiopurines or biologics
Severe
IV steroids → Infliximab (Remicade) or cyclosporine
Acute Severe UC Flare, Inpatient Management Algorithm
Acute Severe UC (Truelove-Witts severe): Admit → IV methylprednisolone 60 mg/day → assess response at Day 3. If no improvement (≥ 8 stools/day or 3–8 stools + CRP > 45): rescue therapy with infliximab or cyclosporine, or colectomy. Do NOT delay surgical consultation. Travis Criteria, 1996
Day 0: Admit. Rule out C. diff (send toxin PCR), CMV colitis (if on immunosuppression, send CMV PCR). IV methylprednisolone 60 mg daily. DVT prophylaxis (UC flares are prothrombotic). NPO if toxic megacolon suspected.
Day 1–3: Monitor stool frequency, CRP, abdominal exam. Flexible sigmoidoscopy (NOT full colonoscopy, perforation risk) to assess severity and rule out CMV.
Day 3 assessment: Responding → transition to oral prednisone 40 mg, plan steroid taper + biologic initiation. NOT responding → infliximab 5 mg/kg (preferred) or IV cyclosporine 2 mg/kg/day. Surgical consultation for colectomy if refractory.
Day 5–7: If rescue therapy failing → subtotal colectomy with end ileostomy is life-saving. Do not delay.
Biologics Comparison Table
Drug
Mechanism
Approved For
Key Pearls
Infliximab (Remicade)
Anti-TNF-alpha (chimeric mAb)
UC + Crohn
Preferred for fistulizing Crohn + acute severe UC. IV infusion. ACT 1/ACT 2, 2005
Adalimumab (Humira)
Anti-TNF-alpha (fully human mAb)
UC + Crohn
SC injection, convenient for outpatient. Less immunogenic than infliximab. CLASSIC I, 2006
Vedolizumab (Entyvio)
Anti-α4β7 integrin (gut-selective)
UC + Crohn
Lower systemic infection risk, does NOT increase TB/opportunistic infection risk. Slower onset (8–14 weeks). Preferred if infection concerns. GEMINI 1, 2013
Ustekinumab (Stelara)
Anti-IL-12/23 (p40 subunit)
Crohn (UC emerging)
IV induction → SC maintenance. Good safety profile. Consider after anti-TNF failure. UNITI-1/UNITI-2, 2016
Tofacitinib (Xeljanz)
JAK inhibitor (small molecule)
UC only
Oral, no infusions. Rapid onset. Risk: VTE, herpes zoster. Avoid in patients with VTE risk factors. OCTAVE, 2017
Choosing a Biologic: Anti-TNF is first-line for most moderate-severe IBD and fistulizing Crohn. Vedolizumab preferred if TB/infection risk is high (gut-selective mechanism). Ustekinumab for anti-TNF failures. Tofacitinib is oral and fast-acting but limited to UC with VTE monitoring required.
Stool studies -C. diff, cultures, O&P (rule out infectious mimics)
CRP, ESR -inflammation markers
Fecal calprotectin -non-invasive marker of intestinal inflammation
CBC (anemia), albumin, iron studies
pANCA (UC ~70%) vs ASCA (Crohn ~60%)
💊 Medications
Drug
Dose
Class
Key Notes
Mesalamine (Asacol)
2.4–4.8 g/day PO
5-ASA
UC first-line mild disease. Minimal role in Crohn.
Budesonide (Entocort)
9 mg daily × 8 wk taper
Steroid
Ileal/right colon Crohn. Less systemic effects than prednisone.
Azathioprine (Imuran)
2–2.5 mg/kg/day
Thiopurine
Steroid-sparing. Check TPMT before starting. Risk: lymphoma, pancreatitis.
Infliximab (Remicade)
5 mg/kg IV wk 0,2,6 then q8wk
Anti-TNF
Moderate-severe IBD. Screen for TB/Hep B before starting.
Vedolizumab (Entyvio)
300 mg IV q8wk
Anti-integrin
Gut-selective. Lower infection risk than anti-TNF.
Ustekinumab (Stelara)
Induction IV → 90 mg SC q8wk
Anti-IL12/23
Moderate-severe Crohn. Growing UC evidence.
📋 On Rounds
Pimp Questions
How do you distinguish Crohn from UC on colonoscopy?
Crohn: Skip lesions (patchy inflammation), cobblestone mucosa, aphthous ulcers, deep linear ulcers, strictures. Can involve terminal ileum. Histology: non-caseating granulomas (found in ~30%). UC: Continuous inflammation starting at rectum extending proximally, loss of vascular pattern, pseudopolyps, friability. Histology: crypt abscesses, crypt architectural distortion.
What must you screen for before starting anti-TNF therapy?
(1) Tuberculosis -QuantiFERON Gold or PPD (anti-TNF reactivates latent TB). (2) Hepatitis B -HBsAg, anti-HBc, anti-HBs (risk of fulminant reactivation). (3) Hepatitis C. (4) Age-appropriate cancer screening. (5) Vaccination status (give live vaccines BEFORE starting, not after).
What is PSC and which IBD is it associated with?
Primary Sclerosing Cholangitis -progressive fibrosis and stricturing of intra/extrahepatic bile ducts. Strongly associated with UC (~70-80% of PSC patients have UC). Diagnosed by MRCP (beading of bile ducts). Increases risk of cholangiocarcinoma. UC + PSC patients have even higher colorectal cancer risk.
A UC patient on azathioprine presents with a flare. What infection must you rule out before escalating immunosuppression?
You must rule out C. difficile (send stool toxin PCR) and CMV colitis (send CMV PCR and request CMV immunohistochemistry on biopsy). Both mimic IBD flares and will worsen with increased immunosuppression. C. diff is extremely common in IBD patients (even without prior antibiotics). CMV colitis occurs in immunosuppressed patients and requires IV ganciclovir, not steroids. Always test before escalating therapy.
Why is vedolizumab considered safer than anti-TNF agents in terms of infection risk?
Vedolizumab targets the α4β7 integrin, which is selectively expressed on gut-homing lymphocytes. This blocks lymphocyte trafficking to the GI tract specifically, without systemic immunosuppression. Unlike anti-TNF agents, vedolizumab does not increase the risk of TB reactivation, opportunistic infections, or systemic infections. Preferred in patients with prior serious infections, latent TB concerns, or elderly patients.
What are the criteria for toxic megacolon and how do you manage it?
Toxic megacolon = radiographic colonic dilation > 6 cm (transverse colon) or cecum > 9 cm PLUS systemic toxicity (fever > 38.6, HR > 120, WBC > 10.5K, or altered mental status). Management: (1) NPO + NG decompression. (2) IV fluids + electrolyte correction. (3) IV broad-spectrum antibiotics. (4) IV methylprednisolone.
What is the role of TPMT testing before starting azathioprine?
TPMT (thiopurine methyltransferase) metabolizes azathioprine/6-MP. ~10% are heterozygous (intermediate activity) and 0.3% are homozygous deficient. Deficient patients accumulate toxic 6-thioguanine nucleotides causing severe myelosuppression. Check TPMT genotype/phenotype before the first dose. Homozygous deficient = absolute contraindication. Heterozygous = start at 50% dose with close CBC monitoring.
When should you consider surgery for Crohn disease?
Surgery in Crohn is not curative (recurs in ~50% within 5 years), reserved for complications: (1) Obstruction/stricture unresponsive to medical therapy. (2) Abscess not drainable percutaneously. (3) Fistula refractory to anti-TNF + surgical drainage. (4) Perforation. (5) Dysplasia/cancer on surveillance. Post-surgical prophylaxis with metronidazole or anti-TNF reduces recurrence. POCER, 2015
How does UC increase colorectal cancer risk and what is the surveillance strategy?
UC-associated CRC follows the inflammation-dysplasia-carcinoma sequence. Risk factors: duration > 8 years, pancolitis, concurrent PSC, family history, persistent inflammation. Surveillance: colonoscopy at 8 years after onset, then every 1-3 years with chromoendoscopy + random biopsies. PSC patients: annual colonoscopy from diagnosis. 5-ASA may be chemoprotective.
Clinical Examples
📋 Case 1, Acute Severe UC Flare
Patient: 34F with known UC (pancolitis, on mesalamine) presents with 3 days of worsening bloody diarrhea (10-12/day), cramping, fever 38.9°C, HR 112.
Labs: WBC 14.2, Hgb 9.8, CRP 62, albumin 2.4, K 3.1. C. diff PCR negative.
Assessment: Meets Truelove-Witts severe criteria. KUB: no toxic megacolon.
Management:
Admit. IV methylprednisolone 60 mg/day. DVT prophylaxis. Correct K.
Flexible sigmoidoscopy day 1-2 for severity + CMV biopsy.
Day 3: 8+ stools/day, CRP 55 → Travis criteria met for steroid failure.
Emergent surgical consult. Serial abdominal exams + KUB q12h.
No improvement 24h → subtotal colectomy with end ileostomy.
Teaching Point: Mortality 20-30% with perforation. Do NOT delay surgery. Intern role: serial exams, trend WBC/lactate, escalate immediately.
⚡ Summary
Crohn or UC
Crohn: transmural, skip lesions, anywhere from mouth to anus, with strictures, fistulas and perianal disease, and granulomas on biopsy.UC: mucosal only, continuous from the rectum proximally, colon only, with no fistulas.Smoking worsens Crohn but is protective in UC, which is one of the few clean epidemiologic dividers between them.
Exclude Infection Before Immunosuppressing
Always rule out C. difficile and CMV colitis before escalating immunosuppression in a flare. Both mimic and both are made dramatically worse by steroids and biologics. CMV in particular hides inside a steroid-refractory UC flare, so a patient who is not responding by day 3 needs the question asked again, with biopsies.
Grade the UC Flare at the Bedside
Truelove and Witts decides admission versus outpatient care.FAST: Fever, Anemia, Six or more stools a day, Tachycardia. Plus raised ESR or CRP and bloody stools. Meeting severe criteria means admit for IV steroids and GI consultation, not a prednisone prescription and a clinic follow-up.
Acute Severe UC Runs on a Day-3 Clock
Admit, give IV methylprednisolone 60 mg daily, and formally assess response on day 3.No improvement, defined as 8 or more stools a day, or 3 to 8 stools with CRP above 45, means rescue therapy now with infliximab or cyclosporine, or colectomy. Prolonging failed steroids is what turns a rescuable flare into an emergency colectomy, and the risk of perforation rises with every extra day.
Toxic Megacolon Is a Surgical Problem
Colonic dilation above 6 cm with systemic toxicity.Get surgery involved, give broad-spectrum antibiotics, stop antidiarrheals, anticholinergics and opioids, which all precipitate it, and be prepared for colectomy. Serial abdominal films and examinations, since the diagnosis is made by watching the trend.
Step-Up Therapy, With the Right Agent
Mesalamine works in UC and is largely ineffective in Crohn.Steroids induce remission but never maintain it, so a patient who cannot come off them needs a maintenance agent, not another course. Thiopurines and methotrexate for maintenance, checking TPMT before azathioprine. Biologics for moderate to severe disease, and increasingly early in high-risk Crohn rather than after everything else has failed.
Choosing a Biologic Is About the Patient, Not the Drug
Anti-TNF is first line for most moderate to severe disease and is the choice for fistulizing Crohn.Vedolizumab when infection or TB risk is high, because it is gut-selective and not systemically immunosuppressing. Ustekinumab after anti-TNF failure.Tofacitinib is oral and works fast in UC, with cardiovascular and thrombotic warnings. Screen for latent TB and hepatitis B before any anti-TNF.
Remember What Happens Outside the Gut
Extraintestinal manifestations that track bowel activity: peripheral arthritis, erythema nodosum, episcleritis. Those that do not: ankylosing spondylitis, primary sclerosing cholangitis, pyoderma gangrenosum, uveitis. PSC in particular is independent of colitis activity and raises colorectal cancer risk enough to need annual colonoscopy. Colorectal cancer surveillance starts 8 years after diagnosis in extensive colitis, and every patient needs bone health, vitamin D, iron and vaccination attention.
SBO: mechanical obstruction (adhesions #1, hernias #2). Ileus: functional without mechanical cause. CT with IV contrast is diagnostic. Most partial SBO resolves with NGT + bowel rest. Surgical emergency if strangulation.
Dilated proximal bowel + decompressed distal bowel + transition point
Diffuse dilation of small AND large bowel, no transition point
Air-fluid levels
Multiple, differential (step-ladder pattern)
Few, similar height
Management
NGT, NPO, IVF. Surgery if complete/strangulated.
Treat underlying cause. Bowel rest. Ambulation.
Signs of strangulation (surgical emergency): Fever, tachycardia, peritonitis, leukocytosis, elevated lactate, non-reducible hernia, pneumatosis on CT. Do NOT delay surgery.
Partial vs Complete SBO
Feature
Partial SBO
Complete SBO
Gas in colon
Present
Absent
Passage of flatus/stool
May continue initially
Absent (obstipation)
CT findings
Transition point with some distal bowel gas
Discrete transition point, no distal gas, "small bowel feces sign"
Conservative trial
Resolves in 60-80% without surgery
Higher failure rate, closer surgical monitoring
Gastrografin useful?
Yes, both diagnostic and therapeutic
Less therapeutic benefit, more for surgical decision-making
Risk Factors for Adhesive SBO
Prior abdominal surgery - single greatest risk factor. Lower GI and pelvic surgeries have highest adhesion rates Menzies & Ellis, Ann Surg 1990
Number of prior laparotomies - risk increases with each additional surgery
Type of surgery - open > laparoscopic for adhesion formation Strik et al, Lancet 2016
Key stat: Adhesive SBO accounts for ~$2.3 billion/year in US healthcare costs and 350,000+ hospital admissions annually. It is the most common cause of surgical emergencies in developed countries.
🚨 Management
Conservative Management (Partial SBO)
NPO -strict bowel rest
NGT to low intermittent suction -decompression
IV fluids -aggressive resuscitation (3rd-spacing)
Electrolyte repletion -K, Mg, PO₄
Serial abdominal exams q4–8h
Water-soluble contrast (Gastrografin) -both diagnostic and therapeutic. If contrast reaches colon by 24h → likely to resolve without surgery
Surgical Indications
Complete SBO with no improvement in 48–72h
Signs of strangulation/ischemia
Closed-loop obstruction
Free air (perforation)
Incarcerated/strangulated hernia
Gastrografin Challenge Protocol
Step
Action
Details
1
Confirm partial SBO
CT showing transition point without signs of strangulation or complete obstruction
2
Administer Gastrografin
100 mL via NGT (clamp NGT for 2h after)
3
Abdominal XR at 8h
Early check for contrast progression
4
Abdominal XR at 24h
Definitive assessment
5a
Contrast in colon at 24h
High likelihood of non-operative resolution. Continue conservative management
5b
No contrast in colon at 24h
Unlikely to resolve. Surgical consultation for operative planning
Evidence:Defined meta-analysis, Br J Surg 2014 Meta-analysis of 14 RCTs: Gastrografin reduced need for surgery (RR 0.62) and shortened hospital stay by ~1.8 days. Contrast reaching the colon within 24h has a 97% sensitivity for predicting non-operative resolution. Branco et al, World J Surg 2010
Timeline for Conservative Management
0-24h: NPO, NGT, IVF, serial exams. Administer Gastrografin if partial SBO
24h: Assess Gastrografin follow-through XR. If contrast in colon, continue conservative Rx
48-72h: Maximum window for conservative trial in partial SBO without improvement
72h+: If no resolution, strongly consider surgical exploration
Bologna Guidelines:Ten Broek et al, World J Emerg Surg 2018 Recommended maximum 72h conservative trial for uncomplicated adhesive SBO. Earlier intervention if clinical deterioration (rising lactate, worsening pain, peritonitis). Delayed surgery associated with higher complication rates and longer hospital stay.
🧪 Workup
CT abdomen/pelvis with IV contrast -gold standard. Shows transition point, dilated vs decompressed bowel, signs of ischemia
Abdominal X-ray -dilated small bowel (> 3 cm), air-fluid levels, absent distal gas (complete SBO)
BMP -dehydration, electrolyte derangements
CBC -leukocytosis (strangulation)
Lactate -elevated with ischemia/strangulation
Lipase -rule out pancreatitis
CT Findings: What to Look For
Finding
Significance
Action
Transition point
Location where dilated bowel transitions to decompressed
Confirms mechanical obstruction vs ileus
Small bowel feces sign
Particulate matter in dilated small bowel proximal to obstruction
Suggests prolonged/complete obstruction Mayo-Smith et al, AJR 1999
Decreased wall enhancement
Bowel wall ischemia
Urgent surgical consultation
Mesenteric haziness/stranding
Venous congestion, early ischemia
Close monitoring, lower threshold for surgery
Pneumatosis intestinalis
Gas in bowel wall - necrosis
Surgical emergency
Portal venous gas
Severe ischemia/necrosis
Surgical emergency
Free fluid
Strangulation until proven otherwise
Surgical consultation
Closed-loop sign
U-shaped or C-shaped dilated loop with convergence of mesentery
High risk for strangulation - surgery
CT accuracy: CT has 94% sensitivity and 96% specificity for SBO diagnosis. For detecting strangulation, sensitivity is 83% and specificity 93%. Defined, Radiology 2009
💊 Medications
Drug
Dose
Purpose
IV Normal Saline
Bolus 1–2 L then maintenance
Volume resuscitation -significant 3rd-spacing
Ondansetron (Zofran)
4 mg IV q6h PRN
Anti-emetic
Gastrografin
100 mL via NGT
Water-soluble contrast -diagnostic and therapeutic (osmotic draws fluid into lumen)
Piperacillin-Tazobactam (Zosyn)
3.375 g IV q6h
If strangulation/perforation suspected -broad-spectrum coverage
AVOID opioids
-
Worsen ileus. Use non-opioid pain management when possible.
📋 On Rounds
Pimp Questions
What is the most common cause of SBO in developed countries?
Adhesions from prior abdominal surgery (60–75%). Second most common: hernias (incarcerated inguinal, ventral, internal). Third: malignancy. In patients with NO prior surgery, always examine for hernias carefully -groin, umbilical, incisional sites.
How does Gastrografin help in SBO management?
Dual role: (1) Diagnostic -if contrast reaches the colon on follow-up XR at 24h, the SBO will likely resolve non-operatively (high negative predictive value for need for surgery). (2) Therapeutic -hyperosmolar → draws fluid into bowel lumen → reduces edema at obstruction point → may help resolve partial SBO. Meta-analyses show reduced need for surgery and shorter hospital stay.
What are the signs of strangulated SBO?
Clinical: Fever, tachycardia, localized peritonitis (rebound/guarding), non-reducible hernia. Labs: Leukocytosis, elevated lactate, metabolic acidosis. CT findings: Mesenteric haziness/fluid, bowel wall thickening, decreased/absent wall enhancement, pneumatosis intestinalis (gas in bowel wall). This is a surgical emergency -do not delay for further workup.
What is the role of CT vs plain film in SBO diagnosis?
CT abdomen/pelvis with IV contrast is the gold standard (94% sensitivity, 96% specificity). Plain films are less sensitive (~70%) and cannot identify the cause, level, or complications of obstruction. CT shows transition point, etiology (adhesion vs hernia vs tumor), and signs of strangulation (decreased enhancement, pneumatosis, portal venous gas). Plain film is acceptable for initial screening in ED but CT should follow.
What is the "small bowel feces sign" on CT?
Particulate matter (gas mixed with solid debris) seen in dilated small bowel proximal to the obstruction. Looks like colonic contents in the small bowel. Indicates prolonged or high-grade obstruction - the stagnant small bowel contents have been broken down by bacteria. Associated with 82% specificity for complete or high-grade SBO. Does NOT necessarily mean strangulation, but indicates the obstruction has been present for some time.
When should you NOT attempt conservative management of SBO?
Go directly to surgery for: (1) Strangulation signs - fever, peritonitis, tachycardia, rising lactate, CT showing ischemia. (2) Closed-loop obstruction - high risk of rapid progression to strangulation. (3) Free air on imaging - perforation. (4) Incarcerated hernia that cannot be reduced. (5) Complete SBO with no improvement after 48-72h of conservative trial. Delayed surgery in strangulated SBO increases mortality from ~5% to 25%+.
What is the difference between SBO in a "virgin abdomen" vs post-surgical?
In a virgin abdomen (no prior surgery), adhesions are NOT the cause. Must evaluate for: incarcerated hernia (examine groin, umbilicus, prior incision sites carefully), malignancy (especially colon/ovarian with peritoneal carcinomatosis), Crohn disease (strictures), gallstone ileus (large gallstone erodes through into duodenum and impacts at ileocecal valve - look for pneumobilia on CT), internal hernia, or Meckel diverticulum. These patients more often require surgery.
What electrolyte abnormalities do you expect in SBO with prolonged vomiting?
Hypochloremic hypokalemic metabolic alkalosis - from loss of gastric HCl and K+ in vomitus. Also: hypovolemia from third-spacing and poor oral intake, prerenal AKI, hypomagnesemia, hypophosphatemia. The alkalosis perpetuates hypokalemia (K+ shifts intracellularly in exchange for H+). Correct the volume deficit and Cl- first (with NS), and the kidneys will retain K+ and correct the alkalosis.
What is the recurrence rate of adhesive SBO after conservative management vs surgery?
After conservative management, recurrence rate is 20-40% within 5 years. After surgical adhesiolysis, recurrence is 15-30% - only slightly lower because surgery itself creates new adhesions. The Defined, Surg Endosc 2014 showed laparoscopic adhesiolysis may have lower recurrence than open. Key prevention strategies: minimize peritoneal trauma, use laparoscopic technique when possible, and consider adhesion barriers in high-risk patients.
Clinical Examples
📋 Case 1 - Partial Adhesive SBO Managed Conservatively
Patient: 58M with PMH of appendectomy 20 years ago presents with 1 day of crampy abdominal pain, nausea, vomiting, and decreased flatus.
Exam: Abdomen distended, diffusely tender without peritonitis. Well-healed RLQ scar. BS hyperactive. T 37.1, HR 95, BP 130/78.
Labs: WBC 9.2, lactate 1.1, BMP with Cr 1.4 (baseline 0.9), K 3.2, Cl 94.
CT: Dilated small bowel to 4.2 cm with transition point in mid-ileum. Decompressed distal bowel. Some gas in colon. No signs of ischemia.
Assessment: Partial adhesive SBO. No strangulation.
Management: NPO, NGT to LIWS, NS at 150 mL/hr, K repletion. Gastrografin 100 mL via NGT. AXR at 24h: contrast in colon. Diet advanced on day 2. Discharged day 3.
📋 Case 2 - Complete SBO with Strangulation Requiring Surgery
Patient: 72F with PMH of hysterectomy and two prior laparotomies presents with 3 days of worsening abdominal pain, no flatus or stool for 48h, and bilious vomiting.
Exam: Distended, rigid abdomen with rebound tenderness in periumbilical area. Absent bowel sounds. T 38.9, HR 120, BP 88/52.
Management: Emergent surgical exploration (no conservative trial). IVF resuscitation. Piperacillin-tazobactam 4.5g IV. Found 30 cm of non-viable ileum. Small bowel resection with primary anastomosis. ICU post-op.
📋 Case 3 - SBO in Virgin Abdomen: Incarcerated Hernia
Patient: 65M with no surgical history presents with acute-onset periumbilical pain x6h, nausea, and 2 episodes of vomiting.
Exam: Firm, tender, non-reducible mass in right inguinal region. Abdomen distended and tympanic. T 37.5, HR 105.
Labs: WBC 11.2, lactate 2.0. BMP unremarkable.
CT: Right inguinal hernia containing small bowel loop. Proximal small bowel dilated. Bowel wall enhancing normally.
Assessment: SBO from incarcerated inguinal hernia. No strangulation yet (lactate mildly elevated but wall enhancing). Virgin abdomen: always examine for hernias.
Management: Attempted bedside reduction failed. Urgent surgical hernia repair with reduction. Viable bowel confirmed intra-operatively. Mesh repair. Diet advanced day 1. Discharged day 2.
⚡ Summary
SBO or Ileus
SBO is mechanical, with a transition point on CT, high-pitched or absent bowel sounds and colicky pain.Ileus is functional, with no transition point, diffusely dilated bowel including the colon, and quiet bowel sounds.The distinction matters because ileus never needs an operation: it needs the cause treated (electrolytes, opioids, post-operative state, sepsis).
Know the Causes
Adhesions are number one, then hernias, then malignancy and Crohn disease.Adhesive SBO drives over 350,000 admissions a year in the US and is the commonest surgical emergency in developed countries. Ask about prior abdominal surgery, and examine every hernia orifice, since an incarcerated hernia is both the cause and the cure.
Partial or Complete
Partial: continued passage of flatus or stool, some gas visible in the colon on imaging, and a good chance of resolving without surgery.Complete: obstipation with no distal gas, which resolves far less often and has a higher strangulation risk. That difference determines how long a conservative trial is reasonable.
Standard Conservative Management
NPO, IV fluids, correct electrolytes, nasogastric decompression for vomiting or significant distension, and serial abdominal examinations.These patients are markedly volume-depleted from third-spacing into obstructed bowel, so the fluid requirement is usually larger than it looks.
The Trial Has a 72-Hour Ceiling
The Bologna guidelines set a maximum 72-hour conservative trial for uncomplicated adhesive SBO.Failure to resolve within that window is itself an indication to operate, and earlier intervention if there is deterioration: rising lactate, worsening pain or peritonitis. Waiting longer only means operating on sicker bowel.
Gastrografin Predicts and Treats
Give water-soluble contrast and repeat the film; contrast reaching the colon within 24 h is about 97% sensitive for successful non-operative resolution.A meta-analysis of 14 randomized trials showed it reduced the need for surgery (RR 0.62) and shortened stay by about 1.8 days.Never use barium, because barium peritonitis after a perforation is catastrophic.
What Forces the Operation
Strangulation is a surgical emergency: fever, tachycardia, peritonitis, leukocytosis, rising lactate, a non-reducible hernia, or pneumatosis on CT. Also closed-loop obstruction, portal venous gas, free air, and failure of the conservative trial.Do not delay for further imaging once these are present.
Read the CT for More Than the Transition Point
CT is 94% sensitive and 96% specific for SBO, but only 83% sensitive for strangulation, so a scan that does not show ischemia does not exclude it and the clinical picture still wins. Look for the small bowel feces sign near the transition point, which suggests a longer-standing obstruction, and for a closed loop, mesenteric haziness, free fluid and a non-enhancing bowel wall. A first-time obstruction in a patient with no prior surgery is malignancy or hernia until proven otherwise, not adhesions.
Murphy sign: inspiratory arrest with RUQ palpation
Severe
Reynolds pentad: Charcot + AMS + shock
Gangrenous, emphysematous, perforated
Key labs
↑ bili, ↑ ALP/GGT, ↑ WBC, + blood cultures
↑ WBC, ± mild LFT elevation
Imaging
CBD dilation > 8 mm, ± stone visible
GB wall thickening, pericholecystic fluid, + Murphy on US
Treatment
ERCP within 24–48h (emergent if septic)
Cholecystectomy within 72h
Reynolds pentad (Charcot triad + AMS + shock) = toxic cholangitis. This is a medical emergency requiring EMERGENT ERCP and ICU admission. Mortality 50% without drainage.
Charcot Triad & Reynolds Pentad
Key point: Charcot triad (fever + RUQ pain + jaundice) has sensitivity of only ~50-70%. Absence does NOT rule out cholangitis. Reynolds pentad adds altered mental status + shock, indicates toxic/suppurative cholangitis requiring emergent intervention.
TG18 Severity Grading, Acute Cholangitis
Grade
Severity
Criteria
Management
Grade I
Mild
Does not meet Grade II or III criteria. Responds to initial antibiotics/fluids
Any 2 of: WBC >12k or <4k, fever ≥39°C, age ≥75, total bili ≥5, albumin <2.5
Antibiotics + urgent ERCP within 24-48h
Grade III
Severe
Organ dysfunction in ≥1: cardiovascular (vasopressors), neurologic (AMS), respiratory (P/F <300), renal (Cr >2.0), hepatic (INR >1.5), hematologic (plt <100k)
Emergent ERCP <12-24h + ICU + organ support
TG18 Guidelines: The Tokyo Guidelines 2018 (TG18) provide the current international standard for diagnosis, severity grading, and management of acute cholangitis and cholecystitis. TG18 (Yokoe et al.), 2018
TG18 Severity Grading, Acute Cholecystitis
Grade
Severity
Criteria
Management
Grade I
Mild
Healthy patient, no organ dysfunction, mild GB inflammation
Diagnostic + therapeutic, stone extraction, stent, sphincterotomy
Sensitivity (CBD stones)
85-92%
95-98% (gold standard)
When to use
Intermediate probability of CBD stone (equivocal US, mild LFT elevation)
High probability CBD stone, confirmed cholangitis, therapeutic intent
Risks
None (non-invasive)
Post-ERCP pancreatitis (5-10%), bleeding, perforation Elmunzer et al., 2012
Key rule
Use to avoid unnecessary ERCP
Use when you plan to intervene
🚨 Management
Acute Cholangitis
IV antibiotics -start immediately after blood cultures
ERCP with sphincterotomy -biliary drainage within 24–48h. Emergent if Reynolds pentad. Khashab et al., 2012
If ERCP fails: percutaneous transhepatic cholangiography (PTC) or surgical drainage
Fluid resuscitation, vasopressors if septic shock
Acute Cholecystitis
Laparoscopic cholecystectomy within 72h -early surgery is safe and reduces hospital stay ACDC Trial, 2013
NPO, IV fluids, antibiotics, pain control
Percutaneous cholecystostomy -if too sick for surgery (bridge procedure)
Biliary Drainage Timing by TG18 Grade
TG18 Grade
Drainage Timing
Method
Key Considerations
Grade I
Elective (within days)
ERCP preferred
Stabilize with antibiotics first. Schedule ERCP during working hours
Grade II
Urgent (24-48h)
ERCP preferred
Start antibiotics immediately. If not responding in 24h, escalate to emergent
Grade III
Emergent (<12-24h)
ERCP. If fails: PTC or surgical drainage
ICU admission. Vasopressors + antibiotics + urgent GI consult
If ERCP fails or unavailable: Percutaneous transhepatic cholangiography (PTC) is the next option. EUS-guided biliary drainage is emerging as alternative. Surgical drainage (open CBD exploration) is last resort with highest morbidity.
Antibiotic Selection by Severity
Severity
First-Line
Alternative
Duration
Mild-Moderate (Grade I-II)
Piperacillin-Tazobactam 4.5g IV q6h
Ceftriaxone 2g IV daily + Metronidazole 500mg IV q8h
4-7 days after source control Van Lent et al., 2019
Severe (Grade III)
Meropenem 1g IV q8h
Imipenem-Cilastatin 500mg IV q6h
7-14 days; de-escalate based on cultures
PCN allergy
Ciprofloxacin 400mg IV q12h + Metronidazole 500mg IV q8h
Aztreonam 2g IV q8h + Metronidazole 500mg IV q8h
Based on severity
Healthcare-associated
Meropenem 1g IV q8h ± Vancomycin (if MRSA risk)
Add antifungal if prior biliary stent/prolonged antibiotics
Blood cultures × 2 -before antibiotics in cholangitis
Lactate -if concern for sepsis
💊 Medications
Drug
Dose
Indication
Piperacillin-Tazobactam (Zosyn)
3.375–4.5 g IV q6h
First-line for moderate-severe (Tokyo Grade II/III), post-ERCP, or healthcare-associated cholangitis/cholecystitis. Covers Pseudomonas + anaerobes + Enterobacterales in one drug -see bile paradox alert below. TG18, 2018
Ceftriaxone (Rocephin) ± Metronidazole (Flagyl)
2 g IV q24h ± 500 mg IV q8h
Acceptable for mild (Tokyo Grade I) community-acquired biliary infection -ceftriaxone concentrates ~40% in bile (levels 5-10x serum). Add metronidazole for anaerobes if biliary-enteric anastomosis or impacted CBD stone. Does NOT cover Pseudomonas, so not for Grade II/III or post-ERCP.
Ciprofloxacin (Cipro) + Metronidazole (Flagyl)
400 mg IV q12h + 500 mg IV q8h
Alternative if PCN allergy
Meropenem (Merrem)
1g IV q8h
Severe/healthcare-associated cholangitis
Ketorolac (Toradol)
15–30 mg IV q6h
Pain -preferred over opioids initially
Why Zosyn beats ceftriaxone for moderate-severe biliary infection (the bile paradox)
Ceftriaxone has ~40% biliary excretion, achieving bile concentrations 5-10x serum levels, which is exactly why it works for mild (Tokyo Grade I) community-acquired biliary infection. But the same property cuts both ways:
No Pseudomonas coverage -matters in healthcare-associated cholangitis, prior ERCP or biliary stenting, recent broad-spectrum exposure, or any Tokyo Grade II/III disease.
No anaerobe coverage -requires metronidazole add-on for B. fragilis. Anaerobic overgrowth is especially a concern with biliary-enteric anastomoses, impacted CBD stones, or any setting where bile stagnates.
Pseudocholelithiasis paradox -the same high biliary concentration causes calcium-ceftriaxone precipitates that look like gallstones on US. Usually reversible within days to weeks of stopping. Higher risk with courses >10-14 days, doses >2 g/day, dehydration, or prolonged NPO (no bile flow to flush the precipitate).
Bottom line: ceftriaxone ± metronidazole is acceptable for Tokyo Grade I community-acquired cholangitis/cholecystitis. Pip-tazo (Zosyn) is first-line for Grade II/III, post-ERCP, healthcare-associated, or any case with prior broad-spectrum exposure -covers Pseudomonas + anaerobes + Enterobacterales in one drug per TG18, 2018.
📋 On Rounds
Pimp Questions
When is emergent vs urgent ERCP indicated in cholangitis?
Emergent (< 12–24h): Reynolds pentad (Charcot + shock + AMS), failing to respond to antibiotics and fluids, organ failure. Urgent (24–48h): Charcot triad without shock, responding to initial resuscitation but needs definitive drainage. Tokyo Guidelines Grade III (organ dysfunction) → emergent. Grade II (non-responding) → urgent. Grade I (mild) → can be semi-elective.
Why is a HIDA scan useful when ultrasound is inconclusive for cholecystitis?
HIDA scan measures gallbladder filling and function. IV radiotracer is taken up by hepatocytes and excreted into bile. If the gallbladder does not fill (non-visualization at 4h), it confirms cystic duct obstruction = acute cholecystitis. Sensitivity 97%, specificity 94%. Most useful when US shows no stones but clinical suspicion is high (acalculous cholecystitis in ICU patients).
What organisms cause cholangitis?
Gram-negatives dominate: E. coli (most common, ~25-50%), Klebsiella, Enterobacter, Pseudomonas. Anaerobes: Bacteroides, Clostridium. Gram-positives: Enterococcus. Polymicrobial in many cases. This is why empiric coverage needs gram-negative + anaerobic coverage (Zosyn, or FQ + metronidazole).
What is the sensitivity of Charcot triad for acute cholangitis?
Only 50-70%. Many patients with cholangitis do NOT present with all three components. Jaundice may be absent early, and elderly/immunosuppressed patients may not mount a fever. The TG18 diagnostic criteria use systemic inflammation markers + cholestasis + imaging findings and are more sensitive. Always consider cholangitis in any patient with biliary dilation and signs of infection.
What is the risk of post-ERCP pancreatitis and how do you prevent it?
Post-ERCP pancreatitis occurs in 5-10% of ERCPs (up to 15-20% in high-risk patients). Risk factors: young age, female sex, normal bilirubin, suspected sphincter of Oddi dysfunction, difficult cannulation. Prevention: rectal indomethacin 100mg given immediately before or after ERCP (Elmunzer et al, NEJM 2012), prophylactic pancreatic duct stent placement in high-risk cases, and aggressive peri-procedural hydration with lactated Ringer's.
When should you get a cholecystectomy after cholangitis from gallstones?
After ERCP for gallstone cholangitis, cholecystectomy should be performed during the same hospitalization (ideally within 72h of ERCP). SUNFLOWER Trial, Lancet 2024 demonstrated that same-admission cholecystectomy significantly reduces recurrent biliary events compared to delayed surgery. If patient is too sick for surgery, interval cholecystectomy within 2-4 weeks.
What is acalculous cholecystitis and who gets it?
Acalculous cholecystitis accounts for 5-10% of acute cholecystitis cases. Occurs in critically ill ICU patients (sepsis, trauma, burns, TPN, prolonged NPO). Pathophysiology: gallbladder stasis + ischemia + bile inspissation without stones. Mortality is 30-50% (much higher than calculous). Diagnosis: HIDA scan (non-visualization) is most sensitive. US may show GB distension, wall thickening, sludge without stones.
How do you risk-stratify patients for choledocholithiasis (CBD stones)?
ASGE risk stratification:High risk (go directly to ERCP): CBD stone on US, clinical cholangitis, or total bili >4 + dilated CBD. Intermediate risk (get MRCP or EUS first): abnormal LFTs, age >55, dilated CBD without visible stone. Low risk (proceed to cholecystectomy with intra-op cholangiogram): normal labs, normal CBD on US, no clinical features. This prevents unnecessary ERCPs in low-risk patients.
Clinical Examples
📋 Case 1, Acute Cholangitis with Sepsis Requiring Emergent ERCP
Patient: 72F presents with 2 days of RUQ pain, fevers to 39.5°C, and jaundice. PMH: cholelithiasis (declined prior cholecystectomy). BP 82/54, HR 118, T 39.8°C, confused and somnolent.
Labs: WBC 22k, total bili 8.2, direct bili 6.1, ALP 580, AST 245, ALT 198, lactate 4.8, Cr 2.1 (baseline 0.9). Blood cultures drawn x2.
Imaging: RUQ US: CBD dilated to 12 mm with shadowing stone in distal CBD. Multiple gallstones in GB.
Assessment:Reynolds pentad (fever + RUQ pain + jaundice + AMS + shock) = TG18 Grade III cholangitis with organ dysfunction (cardiovascular, neurologic, renal).
Management:
Resuscitation: 30 mL/kg LR bolus, norepinephrine started for MAP <65 despite fluids. ICU admission.
Antibiotics: Meropenem 1g IV q8h (Grade III = broad-spectrum) started within 1 hour.
Emergent ERCP: GI consulted immediately. ERCP performed within 8 hours. Sphincterotomy with stone extraction and plastic biliary stent placed. Purulent bile drained.
Post-ERCP: Vasopressors weaned off within 24h. Mental status cleared by 36h. Creatinine normalized by day 3.
Follow-up: Cholecystectomy performed on hospital day 5 after clinical improvement.
Key lesson: Reynolds pentad = TG18 Grade III = emergent ERCP. Do not delay drainage for imaging. Start broad-spectrum antibiotics (meropenem for Grade III) and resuscitate aggressively. Same-admission cholecystectomy once stabilized.
📋 Case 2, Acute Cholecystitis and Timing of Cholecystectomy
Patient: 45M presents with 18 hours of progressively worsening RUQ pain radiating to right scapula, nausea, and one episode of vomiting. No fever initially. Positive Murphy sign on exam. PMH: obesity, no prior biliary disease.
Labs: WBC 14.5k, total bili 1.8 (mildly elevated), ALP 145, AST/ALT mildly elevated, lipase normal.
Imaging: RUQ US: multiple gallstones, GB wall thickening to 5 mm, pericholecystic fluid, sonographic Murphy sign positive. CBD 5 mm (normal).
Assessment: TG18 Grade I acute calculous cholecystitis (healthy patient, no organ dysfunction).
Management:
Initial: NPO, IV NS maintenance, ketorolac 15mg IV q6h for pain, piperacillin-tazobactam 3.375g IV q6h.
Surgery consult: Laparoscopic cholecystectomy scheduled for hospital day 2 (within 72h of symptom onset).
Operative note: Inflamed GB with omental adhesions. No CBD stones on intraoperative cholangiogram.
Post-op: Tolerating diet same evening. Discharged POD1.
Key lesson:ACDC Trial, Ann Surg 2013 showed early cholecystectomy (within 72h) is preferred over delayed surgery. Normal CBD on US + mildly elevated bili = low risk for CBD stones, so intraoperative cholangiogram is sufficient without MRCP.
📋 Case 3, Choledocholithiasis Workup Pathway
Patient: 58F presents with intermittent RUQ pain x3 days, now with dark urine and pale stools. No fever. Vitals stable. RUQ tender but no Murphy sign.
Labs: WBC 9.8k (normal), total bili 3.8, direct bili 2.9, ALP 420, GGT 380, AST 180, ALT 210. Normal lipase.
Imaging: RUQ US: gallstones present, CBD dilated to 9 mm, no definite stone visualized in CBD. No GB wall thickening or pericholecystic fluid.
Assessment: Choledocholithiasis (obstructive pattern LFTs + dilated CBD). No cholangitis (afebrile, normal WBC). No cholecystitis (no Murphy sign, no GB wall changes).
Risk stratification (ASGE):
Dilated CBD (>6mm) + elevated bilirubin + abnormal LFTs = high probability of CBD stone
No CBD stone visualized on US (sens ~50% for CBD stones), but high clinical suspicion
Decision: High risk → proceed directly to ERCP (do not delay with MRCP)
Management:
ERCP: 8mm stone found in distal CBD. Sphincterotomy + balloon sweep with complete stone extraction. Rectal indomethacin 100mg given for post-ERCP pancreatitis prophylaxis.
Post-ERCP: LFTs trending down within 24h. Bili 2.1 → 1.4 by day 2.
Cholecystectomy: Performed same admission (day 3). Uncomplicated.
Key lesson: Use ASGE risk stratification: high risk → ERCP directly. Intermediate risk → MRCP or EUS first. Low risk → proceed to cholecystectomy with intraoperative cholangiogram. Always give rectal indomethacin for post-ERCP pancreatitis prophylaxis.
⚡ Summary
Separate the Two at the Door
Cholangitis is an infected, obstructed bile duct and is a drainage emergency.Cholecystitis is an inflamed gallbladder and is a scheduled operation.Jaundice with a dilated duct and rising alkaline phosphatase points to cholangitis; a positive Murphy sign with a thickened gallbladder wall and pericholecystic fluid points to cholecystitis.
Charcot Triad Misses Half of Them
Fever, right upper quadrant pain and jaundice together are only about 50 to 70% sensitive, so their absence does not exclude cholangitis. Reynolds pentad adds altered mental status and shock and marks suppurative cholangitis. Mortality approaches 50% without drainage, so that patient goes to the ICU and to emergent ERCP, not to the ward for observation.
Drainage Is the Treatment for Cholangitis
Antibiotics alone do not treat an obstructed, infected duct, because the pressurized bile keeps seeding the bloodstream. Grade III (organ dysfunction) → emergent ERCP. Grade II (moderate) → early, within 24 to 48 h. Grade I (mild) → antibiotics with drainage if there is no response.If ERCP fails or is unavailable, percutaneous transhepatic drainage is next, with EUS-guided drainage emerging and surgical exploration a last resort.
Pick the Antibiotic by Severity, and Know Why
Ceftriaxone plus metronidazole is adequate for mild (Tokyo Grade I) disease, since roughly 40% of ceftriaxone is excreted in bile and it reaches concentrations several times serum. Piperacillin-tazobactam or a carbapenem for moderate to severe disease, where the concern is resistant gram-negatives and enterococci rather than biliary penetration. Always draw blood cultures first, and get bile cultures at drainage.
Cholecystitis Goes to Surgery Early
Laparoscopic cholecystectomy within 72 h of symptom onset.Early operation has fewer complications and a shorter stay than delayed interval surgery, and beyond that window inflammation and adhesion make the dissection dangerous. A percutaneous cholecystostomy tube is the bridge for the patient too unwell for anesthesia.
MRCP or ERCP Is a Diagnostic-Versus-Therapeutic Choice
MRCP is diagnostic only and is the right test when the probability of a stone is intermediate.ERCP is therapeutic and carries a pancreatitis risk, so reserve it for patients who need drainage or stone extraction. Doing a diagnostic ERCP on a patient who turns out to have no stone exposes them to a complication for no benefit.
Ultrasound First, But Do Not Stop There
Ultrasound is the first-line test: sensitive for stones, shows wall thickening, pericholecystic fluid and duct dilation, and gives a sonographic Murphy sign. A normal ultrasound does not exclude cholecystitis or a common duct stone. HIDA is the most sensitive test for acute cholecystitis (non-visualization of the gallbladder), and CT is better for complications: perforation, emphysematous change and abscess.
Know the Variants That Behave Differently
Acalculous cholecystitis in the critically ill, on TPN or after major surgery, with a higher rate of gangrene and perforation and often managed with a cholecystostomy tube. Emphysematous cholecystitis, gas in the wall, in diabetics, which is a surgical emergency. Gallstone pancreatitis and Mirizzi syndrome as obstruction mimics. Post-drainage, the stone still has to be dealt with, so plan the definitive cholecystectomy rather than discharging on antibiotics alone.
Acute hepatic inflammation from heavy alcohol use. AST typically 2–6× ULN with AST:ALT >2:1, jaundice, and recent heavy drinking. Maddrey Discriminant Function (DF) ≥32 defines severe disease -consider steroids. MELD score also predicts mortality. Nutrition may be the most important intervention.
🔍 Overview
Definition & Diagnosis
AST typically 2–6× ULN (rarely > 500 in pure alcoholic hepatitis)
AST:ALT ratio > 2:1 -classic pattern (alcohol damages mitochondrial AST, and ALT requires pyridoxal phosphate which is depleted in alcoholics)
Recent heavy alcohol use (typically > 40g/day women, > 60g/day men for > 6 months)
Jaundice (bilirubin often markedly elevated)
Exclude other causes: viral hepatitis, drug-induced, autoimmune
Maddrey Discriminant Function (DF)
DF = 4.6 × (patient PT − control PT) + total bilirubin
High-calorie, high-protein nutrition (35–40 kcal/kg/day) -nutrition may be the single most important intervention
Thiamine (Vitamin B1) 100 mg IV/PO daily
Folic acid 1 mg PO daily
Multivitamin daily
Alcohol cessation -absolute requirement
DF ≥ 32 -Severe
Prednisolone (Orapred) 40 mg PO daily × 28 days → taper
Calculate Lille score at day 7 -this is MANDATORY
Lille > 0.45 = non-responder → STOP steroids (no benefit, only side effects)
Lille < 0.45 = responder → complete 28-day course
PLUS all supportive care above (nutrition, thiamine, folate, MVI)
Contraindications to Steroids
Active GI bleed
Uncontrolled infection
HBV/HCV co-infection
Hepatorenal syndrome
Pentoxifylline for alcoholic hepatitis is DEAD.STOPAH, 2015 showed no benefit. Prednisolone showed modest short-term mortality benefit but no long-term benefit. Nutrition may be the most important intervention.
Updated Practice - Old teaching: pentoxifylline is an alternative to steroids. WRONG -STOPAH definitively showed pentoxifylline doesn't work. Steroids remain the only pharmacologic option for severe AH, but the benefit is modest and short-term.
🧪 Workup
Test
Purpose
AST, ALT
AST:ALT > 2:1 classic. AST rarely > 500.
Total/direct bilirubin
Often markedly elevated (used in DF and MELD)
INR/PT
Synthetic function, used in DF calculation
Albumin
Synthetic function and inflammation (NOT a nutritional marker, see below)
Why prednisolone and NOT prednisone for alcoholic hepatitis?
Prednisolone is the active form. Prednisone is a prodrug that requires hepatic conversion to prednisolone. In a patient with severe alcoholic hepatitis, the damaged liver cannot reliably convert prednisone → prednisolone. Using prednisolone bypasses this step and ensures the patient receives the active drug.
What is the Lille score cutoff and what does it mean?
Lille score > 0.45 at day 7 = non-responder. These patients derive no benefit from continued steroids and are only exposed to steroid side effects (infection, hyperglycemia). Stop steroids immediately. Lille < 0.45 = responder → complete the 28-day course. The Lille model uses day 0 and day 7 bilirubin, albumin, age, creatinine, and PT to predict response.
What did the STOPAH trial show?
STOPAH, 2015 was the largest RCT in alcoholic hepatitis (n=1103). Pentoxifylline showed NO benefit at any time point -it is definitively dead. Prednisolone showed a trend toward reduced 28-day mortality (OR 0.72, p=0.06) but no significant benefit at 90 days or 1 year. Bottom line: steroids provide modest short-term benefit; pentoxifylline provides none.
Why is AST:ALT ratio > 2:1 in alcoholic hepatitis?
Two reasons: (1) Alcohol damages mitochondria, which contain most of the AST (mitochondrial AST isoenzyme is released). ALT is primarily cytoplasmic. (2) Pyridoxal-5-phosphate (active B6) is depleted in alcoholics. ALT requires pyridoxal phosphate as a cofactor more than AST does, so ALT production is impaired. Result: AST rises more than ALT. An AST:ALT >2:1 is ~90% specific for alcoholic liver disease. If AST >500, consider other diagnoses (acetaminophen toxicity, ischemic hepatitis).
What is the role of early liver transplant in severe alcoholic hepatitis?
Traditionally, transplant programs required 6 months of sobriety before listing. However, Mathurin et al, NEJM 2011 showed that early transplant for steroid non-responders (Lille >0.45) improved 6-month survival from 23% to 77%. The ACCELERATE-AH, Hepatology 2021 confirmed these findings. Careful patient selection is key: first liver-decompensating event, strong social support, no other substance abuse, psychiatric evaluation. Relapse rates are comparable to patients transplanted after 6 months of sobriety.
What infections must you screen for before starting steroids?
Steroids in severe AH are immunosuppressive. Before starting, screen for: (1) Spontaneous bacterial peritonitis (SBP) - diagnostic paracentesis if ascites present (PMN >250 = SBP, contraindication to steroids until treated). (2) Blood cultures - active bacteremia. (3) CXR - pneumonia. (4) Urinalysis/culture - UTI. (5) HBV serologies - active HBV is a contraindication (steroids cause viral reactivation). Treat any active infection for 48-72h before starting prednisolone. During steroid therapy, maintain a low threshold to culture - steroids mask fever and inflammatory markers.
Why is nutrition so critical in alcoholic hepatitis?
Virtually all patients with severe AH are malnourished, even those who appear obese (sarcopenic obesity). Malnutrition independently predicts mortality - patients consuming <21.5 kcal/kg/day had 65% mortality vs 33% in those meeting caloric goals. Moreno et al, Gastroenterology 2019 Target: 35-40 kcal/kg/day with 1.2-1.5 g protein/kg/day. Use enteral nutrition (NG feeds) if unable to eat. Protein restriction for encephalopathy is OUTDATED - adequate protein is essential. Consult dietitian early.
How do you differentiate alcoholic hepatitis from other causes of jaundice in an alcoholic patient?
The differential for jaundice in an alcoholic includes: (1) Alcoholic hepatitis - AST:ALT >2:1, AST <500, recent heavy drinking, elevated bilirubin and INR. (2) Decompensated cirrhosis - may overlap; look for portal HTN signs (ascites, varices). (3) Acetaminophen toxicity - AST/ALT often >1000, check level. Alcoholics are at risk (depleted glutathione). (4) Biliary obstruction - dilated ducts on US, elevated ALP/GGT disproportionate to AST. (5) Hepatitis B/C - check serologies. (6) Ischemic hepatitis - AST/ALT >1000, recent hypotension. Liver biopsy is gold standard but rarely needed if clinical picture is classic.
What is the MELD score and how does it compare to Maddrey DF?
MELD = 3.78 x ln(bilirubin) + 11.2 x ln(INR) + 9.57 x ln(creatinine) + 6.43. Both predict short-term mortality: DF >=32 and MELD >21 identify severe AH. MELD has the advantage of including creatinine (captures hepatorenal syndrome) and is more objective (no "control PT" variability). Dunn et al, Hepatology 2005MELD >21 has ~75% sensitivity for 90-day mortality. In practice, calculate both. A high MELD with a Lille >0.45 at day 7 carries >75% 6-month mortality.
Clinical Examples
📋 Case 1 - Severe AH Responding to Steroids
Patient: 52M with 25-year history of heavy alcohol use (12 beers/day), presenting with 3 weeks of progressive jaundice, abdominal distension, and confusion. Last drink 5 days ago.
Labs: AST 340, ALT 120 (ratio 2.8:1), total bilirubin 22, INR 2.4, albumin 2.1, Cr 1.2, WBC 15.8, MCV 108. Hepatitis B/C negative.
Assessment: Severe alcoholic hepatitis (DF 81.8 >= 32). No contraindications to steroids (paracentesis: PMN 80, blood cultures negative, CXR clear).
Management: Prednisolone 40 mg PO daily. High-calorie nutrition (35 kcal/kg/day via oral + NG supplement). Thiamine 100 mg IV, folate 1 mg, MVI. Lactulose for encephalopathy. Day 7 Lille score: 0.18 (responder) - completed 28-day course. Bilirubin trended down to 8 by day 28. Discharged with alcohol cessation program referral.
📋 Case 2 - Severe AH, Steroid Non-Responder
Patient: 45F with daily vodka use x 10 years, presenting with jaundice, RUQ pain, fever 38.5C. AST 280, ALT 90, bilirubin 28, INR 2.8, Cr 1.8, albumin 1.9.
Management: Started prednisolone 40 mg daily. Day 7: bilirubin rose from 28 to 34 (worsening). Lille score = 0.72 (non-responder, >0.45). Prednisolone STOPPED immediately (no benefit, only infection risk). Continued aggressive nutrition. Hepatology consulted for early transplant evaluation given first liver-decompensating event, supportive family, and willingness to pursue sobriety. Listed and transplanted at day 21. Good outcome.
📋 Case 3 - Mild AH with Supportive Care
Patient: 38M presenting with jaundice, nausea, and RUQ tenderness. Drinks 6-8 beers daily x 5 years. AST 220, ALT 85, bilirubin 6.5, INR 1.3, Cr 0.9, albumin 3.2.
Assessment: Mild alcoholic hepatitis. Does NOT meet criteria for steroids (DF < 32).
Management: Supportive care only: high-calorie high-protein diet, thiamine 100 mg PO daily, folate 1 mg, MVI. Alcohol cessation counseling with motivational interviewing. Gabapentin for alcohol cravings. Hepatitis serologies negative. LFTs trended: bilirubin 6.5 -> 3.2 over 2 weeks. Discharged day 5 with outpatient GI follow-up and alcohol treatment program.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 48-year-old man with 20-year history of heavy alcohol use (1 pint vodka daily) presenting with 2 weeks of jaundice, AST 280, ALT 95, bilirubin 18, INR 2.1, Maddrey DF 58 -severe alcoholic hepatitis."
Key Points to Cover on Rounds
Severe alcoholic hepatitis (DF 58). Started prednisolone 40 mg PO daily. Lille score to be calculated on day 7 -if > 0.45 will stop steroids. Hepatitis serologies negative. No active GI bleed, no uncontrolled infection. Nutrition: high-calorie high-protein diet (35 kcal/kg/day), thiamine 100 mg IV, folate 1 mg, MVI. Alcohol cessation counseling initiated. Monitoring: LFTs twice weekly, daily BMP for HRS surveillance, glucose QID on steroids.
Monitoring
Parameter
Frequency
Target / Action
Lille score
Day 7 (MUST calculate)
> 0.45 = stop steroids. < 0.45 = complete course.
LFTs
Twice weekly
Trending bilirubin, AST, ALT improvement
BMP
Daily
Creatinine (HRS surveillance), electrolytes
Infection screening
Ongoing
Steroids mask infection -low threshold to culture
Glucose
QID while on steroids
Steroids cause hyperglycemia -sliding scale insulin
Mental status
Each assessment
Hepatic encephalopathy monitoring
⚡ Summary
Recognize the Pattern
Jaundice and hepatic inflammation on a background of heavy drinking, usually within 8 weeks of the last drink.AST 2 to 6 times the upper limit with an AST:ALT ratio above 2:1, and AST rarely exceeds 500. A transaminase above 500 or an ALT-predominant pattern means look for another cause: viral hepatitis, drug injury, ischemia or acetaminophen.
Score the Severity
Maddrey discriminant function of 32 or more defines severe disease and is calculated from bilirubin and the prothrombin time prolongation. MELD also predicts mortality and is increasingly preferred. Severe untreated disease carries roughly 30 to 50% short-term mortality, which is why the score is calculated on admission rather than at discharge.
Steroids Are the Only Drug, and the Benefit Is Modest
Prednisolone 40 mg daily for 28 days in severe disease (DF 32 or above).STOPAH showed a short-term mortality benefit that did not persist at 90 days and 1 year.Use prednisolone, not prednisone, because conversion to the active form depends on a liver that is failing.
Pentoxifylline Is Dead
Old teaching offered it as an alternative to steroids; STOPAH showed definitively that it does not work. Do not use it, including in patients who cannot take steroids: there is no pharmacologic substitute, and the answer there is supportive care and transplant evaluation, not a drug that does nothing.
Check the Contraindications Before Starting Steroids
Active uncontrolled infection, active gastrointestinal bleeding, hepatorenal syndrome, and untreated sepsis.Screen for infection first, since it is present in a large minority at presentation and steroids given into it are lethal. Treat the infection, then reassess whether steroids are still indicated.
Use the Lille Score at Day 7
A Lille score above 0.45 after 7 days of prednisolone means non-response, so stop the steroid. Continuing beyond that point adds infection risk without benefit. Non-responders should be moved toward transplant evaluation, not toward a longer course.
Nutrition May Be the Most Important Intervention
These patients are profoundly malnourished, and low caloric intake predicts mortality independently of the discriminant function. Target 35 kcal/kg/day and 1.2 to 1.5 g/kg/day of protein, using enteral feeding if intake is inadequate. Do not restrict protein for encephalopathy, which is old teaching that worsens the catabolic state. Give thiamine before any glucose, plus folate and the other B vitamins, and watch for refeeding syndrome.
Do Not Read the Albumin as Nutrition
Albumin is a negative acute phase reactant and a marker of synthetic function and inflammation, not of nutritional status. A low albumin here reflects the liver and the inflammatory state, and it will not rise with feeding. Abstinence is the single strongest determinant of long-term survival, so alcohol use disorder treatment starts during the admission, and early transplant in carefully selected non-responders is now an accepted option rather than a fixed 6-month rule.
AKI in cirrhosis after excluding other causes. Kidneys are structurally normal but functionally failing due to splanchnic vasodilation → systemic underfilling → renal vasoconstriction. Diagnosis of exclusion. Terlipressin FDA-approved 2022. Liver transplant is the only cure.
🔍 Overview
Definition & Classification
HRS-AKI (formerly Type 1): Rapid Cr rise > 0.3 mg/dL in 48h or doubling of Cr within 7 days. Median survival 2 weeks without treatment.
HRS-CKD (formerly Type 2): Gradual, stable Cr elevation. Often associated with refractory ascites.
Pathophysiology
Portal hypertension → splanchnic vasodilation (nitric oxide, other vasodilators)
→ Kidneys are structurally normal but functionally failing
If you transplant these kidneys into a healthy person, they work perfectly
HRS is a diagnosis of EXCLUSION. You MUST rule out: hypovolemia (albumin challenge), ATN (urine Na > 40, muddy brown casts), obstruction (ultrasound), nephrotoxic drugs. If FENa < 1% and bland UA → think HRS.
🚨 Management
Stepwise Approach
Step 1 -Stop nephrotoxins
STOP all nephrotoxic meds, diuretics, beta-blockers, NSAIDs, ACEi/ARBs. These worsen renal perfusion.
Step 2 -Albumin challenge
Albumin 1 g/kg (max 100g) IV × 2 days. Rule out pre-renal AKI. If no Cr improvement → HRS.
Step 3 -Triple therapy (classic)
Midodrine (ProAmatine) 7.5–12.5 mg PO TID + Octreotide (Sandostatin) 100–200 mcg SQ TID + Albumin 25–50g IV daily. Splanchnic vasoconstriction + volume expansion.
Step 4 -Terlipressin (preferred if available)
Terlipressin (Terlivaz) 0.5–1 mg IV q6h + albumin. FDA-approved 2022 based on CONFIRM, 2021. First drug specifically approved for HRS.
Vasopressin analog. FDA-approved for HRS 2022. Preferred over triple therapy if available.
Norepinephrine
0.5–3 mcg/kg/min IV drip
ICU alternative to midodrine/octreotide. More potent vasoconstrictor.
📋 On Rounds
Pimp Questions
What is the pathophysiology of hepatorenal syndrome?
Portal hypertension → splanchnic vasodilation (mediated by nitric oxide and other vasodilators) → effective arterial underfilling → baroreceptor-mediated activation of RAAS, sympathetic nervous system, and ADH → intense renal vasoconstriction → decreased GFR. The kidneys are structurally normal -if transplanted into a healthy recipient, they work perfectly. This is why liver transplant cures HRS.
Why do we give an albumin challenge before diagnosing HRS?
To rule out pre-renal AKI (hypovolemia). Cirrhotics are often volume-depleted from diuretics, GI losses, or poor intake. Albumin 1 g/kg (max 100g) × 2 days provides a structured volume challenge. If creatinine improves → it was pre-renal, not HRS. If no improvement despite adequate volume → diagnosis of HRS is supported. This step is required by diagnostic criteria.
What's new about terlipressin?
Terlipressin (Terlivaz) was FDA-approved in 2022 as the first drug specifically approved for HRS. The CONFIRM trial showed terlipressin + albumin improved verified HRS reversal vs placebo + albumin. Key safety concern: respiratory adverse events, especially in patients who are volume overloaded. Must monitor closely for pulmonary edema.
Why stop beta-blockers in HRS?
Beta-blockers (nadolol, propranolol, carvedilol) reduce cardiac output in cirrhotics who are already hemodynamically compromised. In the setting of HRS, the heart needs to maximize output to compensate for splanchnic vasodilation. Beta-blockers blunt this compensatory response → further reduction in effective arterial volume → worsening renal perfusion.
Clinical Examples
📋 Case 1, HRS-AKI After SBP
Patient: 58M with decompensated cirrhosis (Child-Pugh C), recently treated for SBP. Despite antibiotics and albumin, Cr rising from 1.2 to 3.8 over 4 days. UOP declining.
Key findings: Bland UA (no casts, no proteinuria). FENa < 1%. Urine Na < 10. No nephrotoxin exposure. No response to albumin challenge (1 g/kg x 2 days). Renal US normal.
Management:
Stop diuretics, beta-blockers, NSAIDs, and all nephrotoxins
Start midodrine 7.5 mg PO TID + octreotide 100 mcg SQ TID + albumin 25-50g IV daily
Consider terlipressin if available (FDA-approved 2022) CONFIRM Trial
Hepatology and transplant evaluation, liver transplant is the only definitive cure
Monitor for volume overload (terlipressin risk: respiratory events)
Teaching point: SBP is the most common precipitant of HRS. The kidneys in HRS are structurally normal, if transplanted to a healthy recipient, they work perfectly. The problem is splanchnic vasodilation causing renal vasoconstriction.
📋 Case 2, Differentiating HRS from ATN
Patient: 51F with cirrhosis, admitted with GI bleed and hypotension. Received NS resuscitation. Cr rising from 0.9 to 2.4. UA shows muddy brown casts.
Key findings: FENa 3.2%. Urine Na 45 mEq/L. Muddy brown granular casts on UA. This is ATN from hypoperfusion during the bleed, NOT HRS.
Management:
Supportive care, ATN typically recovers with time
Avoid further nephrotoxins (no contrast, no NSAIDs, no aminoglycosides)
Continue volume resuscitation as needed for the GI bleed
Monitor Cr trend, ATN typically peaks in 7-10 days then recovers
Teaching point: HRS = FENa < 1%, urine Na < 10, bland UA. ATN = FENa > 2%, urine Na > 20, muddy brown casts. This distinction is critical because HRS requires vasoconstrictor therapy while ATN is managed supportively.
📋 Case 3, Terlipressin for HRS-AKI
Patient: 62M with NASH cirrhosis, MELD 32. Cr 4.2, rising despite albumin challenge. Diagnosed with HRS-AKI. Listed for liver transplant but unlikely to receive organ in time.
Key findings: Failed albumin challenge. No other cause of AKI identified. Hemodynamically: MAP 58, tachycardic. Volume status euvolemic by exam.
Management:
Terlipressin 0.5 mg IV q6h (titrate up to 2 mg q6h if Cr not improving) + albumin CONFIRM Trial
TIPS consideration as bridge to transplant in select patients
Dialysis if refractory hyperkalemia, acidosis, or volume overload develops
Teaching point: Terlipressin (FDA-approved 2022) is the first drug specifically approved for HRS. It is a vasopressin analog that causes splanchnic vasoconstriction, redirecting blood flow to the kidneys. Key safety concern: respiratory events, especially in volume-overloaded patients.
Monitoring
Parameter
Frequency
Target / Action
Creatinine
Daily (q12h if ICU)
Trending improvement = therapy working. No response by 48–72h → escalate.
Urine output
Strict I&Os
UOP > 0.5 mL/kg/hr. Oliguria common in HRS.
MAP
Continuous or q4h
Target MAP > 65–70. Midodrine/terlipressin should improve MAP.
Daily weights
Daily
Fluid balance assessment
Hepatic panel
Daily
Underlying liver disease trajectory
⚡ Summary
The Kidneys Are Not the Problem
Splanchnic vasodilation from portal hypertension underfills the systemic circulation, so the kidney vasoconstricts even though it is structurally normal. That is why a biopsy would look unremarkable and why an HRS kidney transplanted into someone else recovers: the lesion is hemodynamic, not parenchymal.
It Is a Diagnosis of Exclusion
Rule out hypovolemia, acute tubular necrosis, obstruction and nephrotoxins before calling it HRS. The pattern that fits is a bland urinalysis, urine sodium below 10 mEq/L and FENa below 1%, with a normal renal ultrasound. Muddy brown casts and a urine sodium above 40 mean ATN, and treating that with vasoconstrictors helps nobody.
The Albumin Challenge Is Both Test and Treatment
Albumin 1 g/kg daily (up to 100 g) for 2 days with all diuretics stopped.Creatinine that improves means the patient was volume-depleted, not in HRS; creatinine that does not improve supports the diagnosis. This step is mandatory before committing to vasoconstrictor therapy.
Stop What Is Making It Worse
Hold diuretics, NSAIDs, aminoglycosides, ACE inhibitors and ARBs, and hold off on contrast.Beta blockers given for varices should be held in refractory ascites and HRS, because the loss of cardiac output reserve worsens renal perfusion in a patient who has none to spare.
Treat With a Vasoconstrictor Plus Albumin
Terlipressin plus albumin is FDA-approved (2022) and is the preferred regimen, with roughly a third of patients achieving HRS reversal. Midodrine 7.5 to 12.5 mg TID plus octreotide 100 to 200 mcg SC TID plus albumin is the outpatient or non-ICU alternative and is considerably less effective. Norepinephrine plus albumin is equivalent to terlipressin in the ICU.Albumin is not optional: it is what restores effective circulating volume so the vasoconstrictor has something to squeeze.
Watch for Terlipressin's Two Harms
Ischemic complications, in the gut, digits and myocardium, so avoid it in known ischemic disease. Respiratory failure, driven by the volume load, which is why it is avoided when ACLF is grade 3 or the patient is already hypoxemic. Monitor oxygenation daily rather than only at the start.
Transplant Is the Only Cure
Everything else is a bridge.Refer for liver transplant evaluation at the time of diagnosis, not after therapy fails: HRS marks end-stage liver disease with a survival measured in weeks to months untreated. Dialysis is a bridge to transplant, not a destination, and offers little to a patient who is not a candidate.
Prevent It Where You Can
Albumin with large-volume paracentesis (8 g per liter removed above 5 liters) prevents post-paracentesis circulatory dysfunction. Albumin plus antibiotics in spontaneous bacterial peritonitis (1.5 g/kg on day 1, 1 g/kg on day 3) cuts HRS and mortality. SBP is the commonest precipitant, so a diagnostic tap is part of the workup of every cirrhotic with a rising creatinine.
Severe fluid and electrolyte shifts when nutrition restarts in a malnourished patient. Insulin surge drives K⁺, Mg²⁺, and especially phosphate intracellularly. Hypophosphatemia is the cardinal lab and can cause cardiac arrest, respiratory failure, rhabdomyolysis, and seizures. Prevent by replacing electrolytes and giving thiamine BEFORE feeding, then start at 5-10 kcal/kg/day.
🔍 Overview
Cardinal sign: hypophosphatemia. Phos < 1.0 mg/dL is life-threatening and can cause cardiac arrest, acute respiratory failure (diaphragm cannot generate ATP), rhabdomyolysis, hemolysis, and seizures within hours of starting feeds. Always check phos before AND daily after restarting nutrition in a malnourished patient.
Mechanism (the insulin surge)
Starvation phase: Body switches from carb to fat and protein metabolism. Insulin drops. Intracellular K⁺, Mg²⁺, and PO₄³⁻ stores are depleted, but serum levels remain deceptively normal because the kidney conserves them.
Refeeding (carb load): Glucose intake triggers an insulin surge. Insulin drives glucose, K⁺, Mg²⁺, and especially phosphate into cells (phos is consumed making ATP for glycolysis and protein synthesis).
Result: Severe extracellular hypoK, hypoMg, and hypoPhos within 24-72 hours of starting feeds. Plus thiamine is consumed in glucose metabolism → risk of Wernicke encephalopathy if not pre-loaded.
Plus: Insulin promotes Na⁺ and water retention → fluid overload, CHF, peripheral edema (worsened by thiamine deficiency cardiomyopathy).
NICE Criteria for High Risk
Patient is HIGH RISK if either: 1 major criterion OR 2 minor criteria.
Major (any 1)
Minor (any 2)
BMI < 16 kg/m²
BMI < 18.5 kg/m²
Unintentional weight loss > 15% in 3-6 months
Unintentional weight loss > 10% in 3-6 months
Little or no nutritional intake > 10 days
Little or no intake > 5 days
Low pre-feeding serum K⁺, Mg²⁺, or PO₄³⁻
History of alcohol abuse, drug use (insulin, chemo, antacids, diuretics)
Classic At-Risk Populations (most common first)
Chronic alcoholism with poor PO intake (also at risk for Wernicke independently)
Anorexia nervosa (the textbook case; BMI often < 15)
Daily multivitamin + thiamine through at least day 10.
Magnesium and zinc help recovery. Continue PO supplementation after IV repletion.
Treating Severe Hypophosphatemia
Severity
Phos level
Treatment
Mild
2.0-2.5 mg/dL
Oral: Neutra-Phos or PhosNak 1-2 packets TID. Recheck in 6 h.
Moderate
1.0-2.0 mg/dL
K-phos or Na-phos 0.16-0.32 mmol/kg IV over 6 h. Use K-phos if K < 4.0, Na-phos if K ≥ 4.0. Recheck phos and Ca after infusion.
Severe
< 1.0 mg/dL OR symptomatic
K-phos 0.32-0.64 mmol/kg IV over 8-12 h. ICU monitoring. Telemetry. Pause or reduce feeds. Recheck phos, Ca, K q6h. Watch for hypocalcemia (phos binds Ca) and metastatic calcification.
Pitfalls when giving IV phosphate: Infuse over ≥ 6 h to avoid hypocalcemia and CaPO₄ precipitation. Do NOT bolus. Watch potassium if using K-phos (each 15 mmol K-phos delivers ~22 mEq K⁺). Avoid in oliguric AKI (can cause hyperphosphatemia and AKI worsening). Do NOT use enteral phos in ileus.
💊 Medications
Key Medications
Drug
Indication
Dose
Notes
Thiamine (Vitamin B1)
Prevent Wernicke + co-factor for glucose metabolism
200-300 mg IV/PO daily × 10 days. If suspected Wernicke: 500 mg IV TID × 3 days then 250 mg daily × 5 days then 100 mg PO daily.
ALWAYS give before any glucose or feeds. Cheap and safe.
K-phos (potassium phosphate)
HypoPhos with K < 4.0
0.16-0.64 mmol/kg IV over 6-12 h depending on severity
Each 15 mmol delivers ~22 mEq K. Cap at 30 mmol per dose. Recheck phos, K, Ca after.
Na-phos (sodium phosphate)
HypoPhos with K ≥ 4.0
Same dosing as K-phos
Use when K is normal or high. Each 15 mmol delivers ~20 mEq Na.
Neutra-Phos / PhosNak (oral)
Mild hypoPhos (2.0-2.5)
1-2 packets PO TID with meals
Each packet = 8 mmol phos. GI side effects (diarrhea) common.
Magnesium sulfate
HypoMg < 1.6
1-2 g IV over 30-60 min q6-8h
Cap at 4-6 g/day. Monitor reflexes (loss of patellar reflex = Mg > 8). Reduce dose in CKD.
KCl (potassium chloride)
HypoK < 3.5
10-40 mEq IV/PO; max IV peripheral 10 mEq/h, central 20 mEq/h
Classic rule: each 10 mEq raises K ~0.1, but that is a best case. Real-world inpatient median is ~0.05 per 10 mEq, and ~0.03 on a loop diuretic, so recheck rather than trusting the arithmetic. Replete Mg first or K won't stay up.
Multivitamin (with B-complex)
Prevent micronutrient deficiencies
1 tab/amp PO/IV daily × at least 10 days
Standard for any malnutrition refeed.
📋 On Rounds
What is the cardinal lab abnormality of refeeding syndrome and why?
Hypophosphatemia. The carb load triggers insulin, which drives phosphate into cells (phos is consumed making ATP and 2,3-DPG for glycolysis and protein synthesis). Serum phos crashes within 24-72 h of starting feeds. Phos < 1.0 mg/dL is life-threatening: cardiac arrest, diaphragmatic failure (can't generate ATP for breathing), rhabdomyolysis, hemolysis, seizures.
Why must thiamine be given BEFORE glucose in alcoholics or any high-risk refeed?
Thiamine is a co-factor for pyruvate dehydrogenase and transketolase, both required for glucose metabolism. A glucose load in a thiamine-deficient patient consumes the last reserves and can precipitate Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia) within hours. Always give thiamine 200-500 mg IV first. Cheap, safe, life-saving.
NICE criteria: when is a patient HIGH RISK for refeeding syndrome?
Either 1 major or 2 minor criteria. Major: BMI < 16, weight loss > 15% in 3-6 mo, no intake > 10 days, low pre-feed K/Mg/phos. Minor: BMI < 18.5, weight loss > 10%, no intake > 5 days, history of alcohol/insulin/chemo/diuretics. Highest-risk patients: anorexia nervosa, chronic alcoholics, oncology cachexia, prolonged NPO > 7 days.
How fast can you advance feeds in a high-risk patient?
Start at 5-10 kcal/kg/day on day 1-2 (use IBW, not actual weight; if BMI < 14 or no intake > 15 days, start at 5). Advance by 5 kcal/kg/day if labs are stable. Reach goal of 25-30 kcal/kg/day by day 5-7. If phos drops > 0.5 mg/dL or K/Mg fall, pause advancement and replete. Limit carbs to 40-50% of calories initially.
A malnourished patient is started on TPN. Day 2: phos 0.8, K 2.9, Mg 1.3, edema, dyspnea. Now what?
Stop or significantly reduce TPN. This is established refeeding syndrome with severe hypoPhos and fluid overload (likely thiamine-deficient cardiomyopathy too). Actions: (1) IV K-phos 0.32-0.64 mmol/kg over 8-12 h. (2) MgSO₄ 2 g IV. (3) KCl repletion. (4) Thiamine 500 mg IV TID. (5) Furosemide if symptomatic CHF. (6) Telemetry. (7) Restart feeds at 5 kcal/kg/day only after labs corrected. (8) Daily weights, BID phos/K/Mg.
Why does refeeding cause heart failure?
Three overlapping mechanisms: (1) Thiamine deficiency cardiomyopathy (wet beriberi): high-output failure from impaired myocardial energy production. (2) Insulin-mediated Na⁺ and water retention in the kidney. (3) Hypophosphatemia impairs myocardial contractility (ATP depletion). Prevent with fluid restriction (20-25 mL/kg/day initially), thiamine pre-load, and slow caloric advancement.
Clinical Examples
📋 Case 1, Anorexia Nervosa Admission
Patient: 22F with anorexia nervosa, BMI 13.8 (75 lb), admitted for medical stabilization. Per family, intake has been minimal for 6 weeks. HR 42, BP 88/56, T 35.6 C. Labs: K 3.1, Mg 1.4, PO₄ 2.2, glucose 68, albumin 3.0, ECG with QTc 510.
Risk assessment: Major criteria met (BMI < 16 AND low pre-feed Mg AND minimal intake > 10 days). VERY HIGH RISK.
Plan:
Telemetry, ICU-level monitoring for 48-72 h
Thiamine 300 mg IV daily × 10 days BEFORE feeds
Multivitamin, folate, B12 IV daily
Replete: KCl 40 mEq IV (in divided doses), MgSO₄ 2 g IV q6h × 3 doses, Neutra-Phos 1 packet PO TID
Recheck phos, K, Mg in 6 h. Once K ≥ 3.5, Mg ≥ 1.6, phos ≥ 2.0 → start nutrition
Day 1: 5 kcal/kg/day (~25 kg actual = 125 kcal/day) via NG tube. Limit carbs.
Advance by 5 kcal/kg/day if labs stable. Reach goal ~25-30 kcal/kg/day by day 5-7.
Multidisciplinary: psychiatry, dietitian, social work, family meetings.
Teaching point: The lower the BMI and the longer the starvation, the slower the advancement. Eating disorder patients are the textbook refeeding case and the highest-mortality scenario. Cardiac arrest from hypoPhos is a real risk in the first week.
📋 Case 2, Chronic Alcoholic, Sepsis Admission, NPO 5 Days
Patient: 58M with alcohol use disorder, admitted for cellulitis, NPO and on IV antibiotics × 5 days. Day 6, switched to general diet plus D5NS at 100 mL/h. Day 7, found confused with ataxia and horizontal nystagmus. Labs: phos 1.4, K 2.8, Mg 1.2, glucose 152.
Diagnosis: Refeeding syndrome WITH iatrogenic Wernicke encephalopathy (dextrose given without prior thiamine in a chronic alcoholic).
Plan:
Stop dextrose-containing fluids. Switch to NS or LR.
Thiamine 500 mg IV TID × 3 days, then 250 mg daily × 5 days, then 100 mg PO daily long-term
K-phos 0.32 mmol/kg IV over 6 h, MgSO₄ 2 g IV q6h × 2, KCl 40 mEq IV total in divided doses
Hold full feeds for 24 h while electrolytes correct, then restart at 5-10 kcal/kg/day with thiamine on board
CIWA monitoring (alcohol withdrawal still possible)
Repeat MRI brain if confusion persists (rule out other causes)
Teaching point: Always give thiamine BEFORE dextrose in any patient with possible alcoholism, eating disorder, or prolonged NPO. The "banana bag" exists for a reason. Wernicke triad (confusion, ataxia, ophthalmoplegia) is present in only ~10% of cases; treat empirically.
📋 Case 3, Post-Whipple, TPN Initiation
Patient: 64F, 8 days post-Whipple for pancreatic adenocarcinoma. Pre-op weight loss 14 kg over 4 months (15% of body weight). NG tube to suction since surgery. Surgical team starts TPN to advance to goal calories over 24 h.
Risk assessment: 1 major criterion (weight loss > 15%) + 2 minor (no intake > 5 days, malignancy/post-op). HIGH RISK.
What went wrong: TPN rate ramped to goal (~2000 kcal/day) in 24 h instead of titrated. Day 2: phos 0.6, K 2.4, Mg 1.0, new arrhythmias on tele.
Recovery plan:
Stop TPN immediately. Telemetry, ICU transfer.
K-phos 0.5 mmol/kg IV over 8-12 h (severe hypoPhos). Recheck phos, Ca, K q4-6h.
MgSO₄ 4 g IV over 4 h, KCl 60 mEq total in divided IV doses
Thiamine 200 mg IV daily, multivitamin daily
After labs corrected (phos ≥ 2.0, K ≥ 3.5, Mg ≥ 1.6): restart TPN at 5-10 kcal/kg/day. Advance by 5 kcal/kg/day. Daily phos/K/Mg.
Teaching point: TPN is the highest-risk refeeding scenario because every calorie is delivered without GI absorption barriers. Always start at 5-10 kcal/kg/day and advance over 5-7 days. Surgery teams sometimes ramp to goal too fast; the medicine consultant should slow it down.
📣 Sample Presentation
One-Liner
"Ms. Park is a 28-year-old with anorexia nervosa, BMI 14, admitted for medical stabilization. She meets NICE high-risk criteria for refeeding syndrome and is being refed at 5 kcal/kg/day with daily phos, K, and Mg monitoring on telemetry."
Key Points to Cover on Rounds
Risk: BMI 14, weight loss > 15% in 3 mo, minimal intake × 6 wk = major NICE criteria. Pre-feed labs: K 3.1, Mg 1.4, phos 2.2, ECG QTc 510. Repleted to K 3.7, Mg 1.8, phos 2.4 before feeding. Started 5 kcal/kg/day NG day 1, now day 4 at 15 kcal/kg/day, phos remained 2.0-2.5, K 3.5-4.0, Mg 1.7-2.0. Thiamine 300 mg IV daily × 10. Multivitamin, fluid restrict 20 mL/kg/day. Daily weights stable. Plan: continue 5 kcal/kg/day advance, target goal 25 kcal/kg by day 7. Telemetry through day 5. Psychiatry following.
Daily Rounds Checklist
Phos, K, Mg checked today? Any drop > 0.5 mg/dL in phos = pause advancement
Discussion with dietitian about kcal target and macros?
⚡ Summary
Quick Reference
The Mechanism Explains Every Rule
Reintroducing carbohydrate triggers an insulin surge, which drives potassium, magnesium and especially phosphate into cells. A starved patient is already depleted of all three despite normal serum levels, because chronic depletion is intracellular. The serum values before feeding are falsely reassuring, which is why the syndrome catches people out.
Hypophosphatemia Is the Cardinal Sign
Phosphate below 1.0 mg/dL is life-threatening.It causes cardiac arrest, acute respiratory failure because the diaphragm cannot generate ATP, rhabdomyolysis, hemolysis and seizures, within hours of starting feeding. ATP and 2,3-DPG synthesis both fail, so oxygen delivery and muscle function collapse together.
Identify the High-Risk Patient Before Feeding
NICE criteria: BMI below 16, unintentional weight loss above 15% in 3 to 6 months, little or no intake for more than 10 days, or low baseline potassium, phosphate or magnesium.Two lesser criteria also qualify. Classic populations: anorexia nervosa, alcohol use disorder, prolonged fasting or NPO status, malabsorption, advanced malignancy, and the post-operative patient who has not eaten.
Give Thiamine Before Any Calories
Thiamine 100 to 300 mg IV daily for at least 3 days, before the first feed and before any glucose-containing fluid.Carbohydrate metabolism consumes thiamine, so feeding a depleted patient precipitates Wernicke encephalopathy, which is preventable and frequently irreversible once it occurs.
Start Low and Advance Slowly
Begin at about 10 kcal/kg/day, or 5 kcal/kg in the most severe cases, and increase over 4 to 7 days to goal.The instinct to correct malnutrition quickly is exactly what causes the syndrome. Slow advancement, not a particular feeding route, is what makes it safe: it happens with oral, enteral and parenteral nutrition alike.
Correct the Electrolytes Before and During, Not After
Replete potassium, magnesium and phosphate before starting and continue to replace aggressively as feeding proceeds.Do not delay feeding to normalize them fully, but do not advance calories while they are falling. Correct magnesium, or the potassium will not correct.
Monitor Daily Through the First Week
Phosphate, potassium and magnesium daily for at least the first 3 to 7 days, with cardiac monitoring in high-risk patients.The nadir typically occurs on days 2 to 4, so a normal set of labs on day 1 is not reassurance. Also watch fluid balance, since sodium and water retention cause edema and can precipitate heart failure in a deconditioned myocardium.
Treat Severe Hypophosphatemia Intravenously
Phosphate below 1.0 mg/dL needs IV replacement, using potassium phosphate or sodium phosphate depending on the potassium, with rechecks every 6 to 12 h. Reduce or hold the calories while correcting rather than pushing on. Watch for hypocalcemia from calcium-phosphate precipitation, and never run phosphate in the same line as calcium.
Key concept: Hypernatremia is almost always a disease of impaired thirst or impaired access to water, not excess sodium. A conscious patient with access to water will drink before Na rises significantly. The populations at highest risk are: intubated ICU patients, elderly with dementia, infants, and post-neurosurgical patients with DI. Adrogue & Madias, NEJM 2000
🚨 Management
Stepwise Approach
Step 1 -Calculate free water deficit
FWD = TBW × (Na/140 − 1) TBW = weight (kg) × 0.5 (women) or 0.6 (men) Example: 70 kg man, Na 160 → TBW = 42 L → FWD = 42 × (160/140 − 1) = 42 × 0.143 = 6 L deficit
Step 2 -Replace free water
D5W IV (250–500 mL/hr) or 0.45% NS or free water via NG/PO if able to take PO. Add ongoing losses to replacement calculation.
Step 3 -Correct at safe rate
≤10 mEq/L per 24 hours for chronic hypernatremia (> 48h). Overcorrection risk: cerebral edema. Acute hypernatremia (< 48h, e.g., ICU patient who missed free water) can be corrected faster.
Step 4 -Treat underlying cause
Desmopressin (DDAVP) for central DI. Stop offending drugs for nephrogenic DI (lithium, etc.). Treat hyperglycemia if osmotic diuresis.
Correct Na ≤10 mEq/L in 24 hours for chronic hypernatremia (> 48h). Rapid correction → cerebral edema → herniation. For acute hypernatremia (< 48h, e.g., ICU patient who missed free water), faster correction is safe.
Do NOT use NS (154 mEq/L Na) to correct hypernatremia if Na is > 154 -NS is hypotonic relative to the patient but still has a lot of sodium. Use D5W or 0.45% NS instead.
IV Fluid Selection Guide
Fluid
Na Content
Free Water per Liter
When to Use
D5W
0 mEq/L
1000 mL
Best for pure free water deficit. Glucose metabolized, leaves pure water. First-line for most hypernatremia
0.45% NS (half-normal)
77 mEq/L
~500 mL
Provides free water + some sodium. Good when patient is also volume depleted
0.9% NS (normal saline)
154 mEq/L
~0 mL
Only for initial volume resuscitation in hypotensive patients. Does NOT correct hypernatremia efficiently
Free water (PO/NG)
0 mEq/L
1000 mL
Most physiologic route if patient has NG or can drink. Preferred when possible
Practical tip:Adrogue & Madias, NEJM 2000 The Adrogue-Madias formula predicts the change in serum Na per liter of any IV fluid: Change in Na = (infusate Na - serum Na) / (TBW + 1). For D5W (infusate Na = 0) in a 70 kg man (TBW = 42): change = (0 - 160) / 43 = -3.7 mEq/L per liter of D5W. So ~2.7 L of D5W over 24h would lower Na by ~10 mEq/L.
🧪 Workup
Test
Purpose
BMP
Na level, Cr (dehydration), glucose (osmotic diuresis)
Serum osmolality
Always elevated in true hypernatremia (> 295)
Urine osmolality
High (> 600): appropriate ADH response -not getting enough water. Low (< 300): DI -kidneys not concentrating urine
Urine Na
Helps differentiate renal vs extrarenal losses
Glucose
Rule out osmotic diuresis from hyperglycemia
Urine specific gravity
Low in DI, high in appropriate response
Diabetes Insipidus Workup
Urine osm < 300 → suspect DI
Give DDAVP → if urine concentrates (osm > 600) = Central DI (responds to exogenous ADH)
If no response to DDAVP = Nephrogenic DI (kidneys resistant to ADH)
💊 Medications
Drug
Dose
Indication
D5W
250–500 mL/hr IV (adjust to correction rate)
Primary free water replacement -no sodium
0.45% NS (half-normal saline)
Variable rate IV
Alternative to D5W -provides some sodium + free water
Desmopressin (DDAVP)
1–2 mcg IV or SQ
Central DI -replaces deficient ADH
Free water flushes
200–500 mL via NG q4–6h
Enteral free water if NG access available -most physiologic
📋 On Rounds
Pimp Questions
How do you calculate the free water deficit?
FWD = TBW × (Na/140 − 1). TBW = weight (kg) × 0.6 (men) or 0.5 (women). Example: 70 kg man, Na 160 → TBW = 42 L → FWD = 42 × (160/140 − 1) = 42 × 0.143 = 6 liters. Important: this estimates the deficit at a single point in time. You must also account for ongoing losses (urine, insensible) and recheck Na frequently. Replace the deficit over 48–72h to avoid overcorrection.
How do you differentiate central vs nephrogenic DI?
Both present with polyuria and dilute urine (urine osm < 300). Give DDAVP (exogenous ADH): if urine concentrates (> 600 mOsm) → Central DI (the pituitary isn't making ADH, but the kidneys can respond). If urine stays dilute → Nephrogenic DI (kidneys are resistant to ADH). Common causes: Central = post-neurosurgery, pituitary tumors, brain death. Nephrogenic = lithium (#1), hypercalcemia, hypokalemia.
Why not use NS to correct severe hypernatremia?
NS contains 154 mEq/L of sodium. If the patient's Na is > 154, NS is actually hypotonic relative to them and will technically lower Na -but very slowly because it still contains a lot of sodium. For efficient free water replacement, use D5W (distributes as pure free water once glucose is metabolized) or 0.45% NS (77 mEq/L Na -provides free water while maintaining some tonicity). D5W is preferred for significant hypernatremia.
What is the maximum correction rate for chronic hypernatremia?
≤10 mEq/L per 24 hours. In chronic hypernatremia (> 48h), brain cells generate idiogenic osmoles (organic osmolytes -taurine, glutamine, etc.) to prevent cellular dehydration. Rapid correction removes these osmoles faster than the brain can adapt → water shifts INTO brain cells → cerebral edema → herniation. For acute hypernatremia (< 48h), the brain hasn't had time to accumulate osmolytes, so faster correction (1–2 mEq/h) is safe.
What are idiogenic osmoles and why do they matter?
In chronic hypernatremia (>48h), brain cells generate organic osmolytes (taurine, glutamine, myo-inositol, sorbitol) to maintain intracellular tonicity and prevent cellular dehydration. These are called "idiogenic osmoles." They take 24-48 hours to accumulate and days to dissipate. If you correct Na too rapidly, water rushes into brain cells (still loaded with osmolytes) causing cerebral edema and herniation. This is why chronic hypernatremia must be corrected slowly (<=10 mEq/L per 24h). Adrogue & Madias, NEJM 2000
What is the most common cause of hypernatremia in hospitalized patients?
Inadequate free water administration, especially in patients who cannot drink independently: intubated patients, altered mental status, post-surgical NPO, elderly with impaired thirst. Hospital-acquired hypernatremia is associated with increased mortality (40-60% in ICU patients) and is considered a marker of poor care quality. Lindner et al, Crit Care 2013 Prevention: calculate maintenance free water needs for all patients who cannot drink (typically 25-30 mL/kg/day).
How does lithium cause nephrogenic DI?
Lithium enters collecting duct principal cells via ENaC channels and inhibits glycogen synthase kinase-3 (GSK3), which is required for aquaporin-2 (AQP2) trafficking to the apical membrane. Without AQP2 channels at the cell surface, the collecting duct cannot reabsorb water in response to ADH. Occurs in 20-40% of chronic lithium users. May be partially reversible if lithium is discontinued early, but prolonged use causes permanent tubulointerstitial fibrosis. Amiloride can help by blocking lithium entry into the cell via ENaC. Bedford et al, JASN 2003
Why is the free water deficit formula an underestimate?
The FWD formula (TBW x [Na/140 - 1]) calculates the static deficit at one point in time. It does NOT account for: (1) Ongoing losses - insensible losses (~500-1000 mL/day), urine free water losses (especially in DI where UOP can be 3-20 L/day), GI losses. (2) TBW is estimated, not measured - obese, elderly, and cachectic patients have different TBW fractions. (3) The formula assumes a closed system with no additional losses. Practical approach: calculate the deficit, add estimated ongoing losses, start replacement, and recheck Na every 4-6 hours to adjust the rate.
What is the approach to hypernatremia in the ICU patient on continuous tube feeds?
ICU patients on tube feeds are at high risk for hypernatremia because: (1) Tube feed formulas have high osmolar loads that require free water to excrete. (2) Patients cannot self-regulate thirst. (3) Loop diuretics, osmotic agents (mannitol), and insensible losses add to the deficit. Management: (1) Order scheduled free water flushes (200-500 mL q4-6h via NG/PEG), not just "PRN." (2) Calculate total free water content of the tube feed formula (typically 70-85% of volume). (3) Monitor Na q6-8h. (4) Consider switching to a lower-osmolality formula if persistent hypernatremia. Alansari et al, J Crit Care 2018
📣 Sample Presentation
One-Liner
"Mrs. Johnson is an 82-year-old woman from a nursing home, found lethargic with Na 162, BUN 45, Cr 1.8, urine osm 650 -hypernatremia from inadequate free water intake with appropriate ADH response."
Key Points to Cover on Rounds
Hypernatremia (Na 162) from inadequate oral intake. Urine osm 650 = appropriate ADH response (not DI). Free water deficit: ~5.3 L. Replacing with D5W at 250 mL/hr + free water via PO as tolerated. Target correction ≤10 mEq/24h. Na last check 4h ago: 158 (trending appropriately). Strict I&Os. Repeat Na in 4h. Addressing underlying cause: speech therapy for dysphagia evaluation, assisted feeding.
Monitoring
Parameter
Frequency
Target / Action
Serum Na
q4–6h during correction
Decrease ≤10 mEq/24h for chronic. Faster OK if acute (< 48h).
I&Os
Strict
Track free water replacement and ongoing losses
Urine output
Hourly
Polyuria in DI (can be > 3–20 L/day)
Daily weights
Daily
Fluid balance tracking
Serum osmolality
q12–24h
Should normalize with Na correction
Clinical Examples
📋 Case 1 - Hospital-Acquired Hypernatremia in Intubated Patient
Patient: 68M intubated for respiratory failure (pneumonia). Day 5 in ICU. BMP: Na 158 (was 140 on admission), Cr 1.0, BUN 28. Urine osm 750 (appropriately concentrated). On NS at 75 mL/hr for maintenance. No free water flushes ordered.
Assessment: Hospital-acquired hypernatremia from inadequate free water. Urine osm >600 = ADH is working (NOT DI). The patient is getting NS (154 mEq/L Na) as maintenance and cannot drink. Classic preventable ICU complication.
Free water deficit: TBW = 70 kg x 0.6 = 42 L. FWD = 42 x (158/140 - 1) = 42 x 0.129 = 5.4 L. Plus ~1.5 L/day ongoing insensible losses.
Management: Changed maintenance to D5W at 200 mL/hr. Added free water flushes 250 mL via NG q4h. Target correction: <=10 mEq/24h. Na rechecked q4h. Na 152 at 12h, 148 at 24h (on target). Continued D5W + free water until Na normalized.
📋 Case 2 - Central Diabetes Insipidus Post-Neurosurgery
Patient: 45F post-op day 1 from transsphenoidal pituitary adenoma resection. Nursing reports UOP 600 mL/hr x 3 hours. BMP: Na 151 (was 138 pre-op). Urine osm 85 (dilute). Urine specific gravity 1.001.
Assessment: Central DI from pituitary stalk manipulation/damage. Acute onset. Classic triad: polyuria (>300 mL/hr), dilute urine (osm <300), rising Na.
Workup: Gave DDAVP 1 mcg IV. Urine osm rose to 680 within 2h = central DI confirmed (kidneys respond to exogenous ADH).
Management: DDAVP 1 mcg IV q12h. D5W at 250 mL/hr to replace ongoing free water losses. Match IV rate to UOP. Na corrected to 143 by 24h. Post-surgical central DI may be transient (resolves in days-weeks) or permanent. Follow Na and UOP closely.
📋 Case 3 - Chronic Hypernatremia in Nursing Home Resident
Patient: 88F from nursing home, found lethargic. Na 172, Cr 2.8 (baseline 1.0), BUN 65, glucose 110. Urine osm 620. Mucous membranes dry, skin tenting, tachycardia.
Assessment: Severe chronic hypernatremia from dehydration (inadequate oral intake). Urine osm >600 = appropriate ADH response, kidneys are concentrating maximally. Prerenal AKI from volume depletion. Duration unknown but likely >48h (chronic).
Free water deficit: TBW = 50 kg x 0.5 = 25 L. FWD = 25 x (172/140 - 1) = 25 x 0.229 = 5.7 L. Plus significant volume depletion.
Management: First: NS bolus for hemodynamic stabilization (this patient is also volume depleted, not just free water depleted). Then: D5W at 150 mL/hr + free water via NG 200 mL q6h. Target: Na decrease <=10 mEq/24h. Too-rapid correction risks cerebral edema (idiogenic osmoles). Na trended: 172 -> 164 at 24h -> 156 at 48h -> 148 at 72h. AKI resolved with volume repletion.
⚡ Summary
It Is a Water Problem, Not a Salt Problem
Sodium above 145 is almost always free water deficit.A conscious patient with access to water will drink long before the sodium rises, so hypernatremia means impaired thirst or impaired access: the intubated, the elderly, the demented, infants, and anyone dependent on someone else for water.
Sort the Causes
Inadequate intake (altered mental status, intubated without free water, elderly). Renal losses: diabetes insipidus, central or nephrogenic, and osmotic diuresis from hyperglycemia, mannitol or high-protein feeds. GI losses: diarrhea, vomiting, nasogastric suction. Rarely true sodium excess, from hypertonic saline, sodium bicarbonate or salt ingestion.
Use the Urine to Localize It
Concentrated urine, osmolality above 700, means the kidney is responding appropriately and the losses are extrarenal or intake is inadequate.Inappropriately dilute urine in a hypernatremic patient means diabetes insipidus, and a water deprivation test with desmopressin then separates central (responds) from nephrogenic (does not).
Correct Chronic Hypernatremia Slowly
No more than 10 mEq/L in 24 hours when it has been present beyond 48 h. Brain cells generate idiogenic osmoles to survive the hypertonic state; lowering the serum osmolality faster than those clear draws water into the brain and causes cerebral edema and herniation. Acute hypernatremia developing within 48 h can be corrected faster, because the osmoles have not accumulated.
Pick the Right Fluid
D5W is pure free water and corrects fastest. 0.45% saline when volume also needs replacing. Enteral free water via the feeding tube is effective, cheap and safe and is under-used in tube-fed patients. Do not use normal saline to correct a sodium above 154: at 154 mEq/L it is only relatively hypotonic and it corrects glacially while loading sodium.
Restore Perfusion Before You Chase the Number
If the patient is hypotensive, give isotonic fluid first. Circulation takes priority over tonicity; the sodium can be addressed once the patient is perfused.
Calculate, Then Verify
Free water deficit = total body water × (serum Na / 140 − 1), using 0.5 × weight in men and 0.4 in women, less in the elderly. Adrogue-Madias predicts the change in sodium per liter of any fluid: (infusate Na − serum Na) / (TBW + 1).Both formulas ignore ongoing losses, so add maintenance and replace what continues to be lost, and treat the numbers as a starting rate rather than an answer.
Recheck Often and Fix the Cause
Sodium every 4 to 6 h while actively correcting, and adjust the rate on the measured trajectory, not on the calculation. Treat the underlying problem or it recurs: desmopressin for central DI, remove the offending drug and correct calcium and potassium in nephrogenic DI, control the glucose in osmotic diuresis, and write free water flushes into the tube feed orders.
Gallstones cause ~40% of acute pancreatitis. Stone impacts at ampulla of Vater → blocked pancreatic duct → autodigestion. Key difference from alcoholic pancreatitis: gallstone pancreatitis needs CHOLECYSTECTOMY during the same admission. ALT > 150 has ~85% PPV for gallstone etiology.
🔍 Overview
Epidemiology & Pathophysiology
Gallstones cause ~40% of acute pancreatitis (alcohol ~40%, other ~20%)
Stone impacts at ampulla of Vater → blocked pancreatic duct → premature activation of pancreatic enzymes → autodigestion
Key difference from alcoholic pancreatitis: gallstone pancreatitis needs CHOLECYSTECTOMY
Diagnosis
Lipase > 3× ULN -most sensitive and specific single test
ALT > 150 U/L has ~85% PPV for gallstone etiology -very helpful clue!
RUQ ultrasound showing gallstones ± CBD dilation
Clinical: epigastric/RUQ pain radiating to back, nausea/vomiting
🚨 Management
Initial Management (Same as All Pancreatitis)
Goal-directed IV LR -NOT aggressive fluids. WATERFALL, 2022 showed aggressive fluids ↑ fluid overload without benefit.
Pain control -hydromorphone/morphine, ondansetron for nausea
Early feeding -low-fat solid diet as tolerated. No need to wait for lipase to normalize.
NO prophylactic antibiotics
Cholecystectomy Timing
Severity
Timing
Rationale
Mild pancreatitis
Same admission (ideally within 72h)
Delaying to outpatient → 25–30% recurrence rate. PONCHO, 2015 showed same-admission chole is safe and reduces recurrence.
Severe/necrotizing
Delay 4–6 weeks
Operating during severe pancreatitis = higher complication rate. Wait for inflammation to resolve.
ERCP Indications
Only if concurrent cholangitis (fever + jaundice + RUQ pain = Charcot triad)
OR persistent CBD obstruction (elevated bilirubin not improving)
Routine ERCP for all gallstone pancreatitis is NOT recommended -APEC, 2024
Do NOT discharge gallstone pancreatitis without cholecystectomy or a plan for same-admission cholecystectomy. Recurrence rate is 25–30% if you send them home with gallbladder in situ. PONCHO, 2015 showed same-admission cholecystectomy is safe and reduces recurrence.
Updated Practice - Old teaching: get ERCP for all gallstone pancreatitis. WRONG -ERCP is only indicated if there is concurrent cholangitis (Charcot triad) or persistent bile duct obstruction. Routine ERCP in resolving gallstone pancreatitis does not improve outcomes.
BISAP Score (predict severity at admission): BUN > 25, Impaired mental status, SIRS, Age > 60, Pleural effusion. Score >= 3 = predicted severe pancreatitis. Simple, fast bedside tool. Use within 24h of admission to guide ICU triage and resource planning.
When to get CT: Do NOT get CT at presentation (too early for necrosis). CT is indicated at 72-96h IF: (1) no clinical improvement, (2) worsening despite treatment, (3) suspected local complication (necrosis, pseudocyst, abscess). Contrast-enhanced CT is the gold standard for detecting pancreatic necrosis (>= 30% non-enhancement = necrotizing pancreatitis). ACR, 2019
Early feeding is safe: Start low-fat solid diet within 24h as tolerated. No need to wait for pain resolution or lipase normalization. Clear liquid progression is unnecessary - go straight to low-fat solids. Early feeding reduces hospital stay and infectious complications. If unable to eat after 72h, start enteral nutrition (nasogastric or nasojejunal tube). TPN only as last resort. Bakker et al. (PYTHON), 2014
Rectal indomethacin for post-ERCP pancreatitis: When ERCP IS indicated (cholangitis, persistent obstruction), give indomethacin 100 mg PR immediately before or after the procedure. Reduces post-ERCP pancreatitis from ~17% to ~9% in high-risk patients. Now standard of care at all major centers. Elmunzer et al. (NEJM), 2012
🧪 Workup
Test
Purpose / Key Values
Lipase
> 3× ULN diagnostic. Don't need to normalize before feeding/surgery.
Severity marker. CRP > 150 at 48h suggests severe pancreatitis.
RUQ ultrasound
Gallstones, CBD dilation (> 6 mm suggests obstruction)
MRCP
If diagnostic uncertainty -avoids invasive ERCP. Better for CBD stone detection.
CT abdomen/pelvis
Only if not improving by day 3–5 (assess for necrosis, complications)
💊 Medications
Drug
Dose
Notes
Lactated Ringer's
Goal-directed (not aggressive)
WATERFALL 2022: aggressive fluids ↑ overload, no benefit
Hydromorphone (Dilaudid)
0.5–1 mg IV q3–4h PRN
Pain control. Morphine is also acceptable.
Ondansetron (Zofran)
4 mg IV q6h PRN
Nausea/vomiting
NO prophylactic antibiotics
-
Antibiotics only if infected necrosis or cholangitis confirmed
📋 On Rounds
Pimp Questions
When should you get an ERCP in gallstone pancreatitis?
Only two indications: (1) Concurrent cholangitis -Charcot triad (fever + jaundice + RUQ pain). ERCP for biliary decompression. (2) Persistent CBD obstruction -bilirubin not improving, CBD remains dilated. Routine ERCP for all gallstone pancreatitis is NOT recommended. APEC, 2024 showed no benefit of early routine ERCP.
What is the significance of ALT > 150 in pancreatitis?
ALT > 150 U/L has ~85% positive predictive value for gallstone etiology. This is one of the most useful lab clues to distinguish gallstone pancreatitis from alcoholic pancreatitis. It reflects transient biliary obstruction causing hepatocyte injury. A normal ALT does not rule out gallstones, but a markedly elevated ALT strongly supports it. Always get a RUQ ultrasound to confirm.
Same-admission vs delayed cholecystectomy -what does the evidence say?
PONCHO, 2015 showed same-admission cholecystectomy (within 72h) for mild gallstone pancreatitis reduced gallstone-related complications from 17% to 5%. The recurrence rate if you discharge without chole is 25–30%. For severe/necrotizing pancreatitis, delay 4–6 weeks (operating in acute severe inflammation ↑ complications).
Why not routine ERCP for gallstone pancreatitis?
Most gallstones that cause pancreatitis pass spontaneously -the stone transiently impacts the ampulla then dislodges. By the time you do ERCP, the stone is often already gone. APEC, 2024 confirmed that routine ERCP in gallstone pancreatitis (without cholangitis) does not improve outcomes and exposes patients to ERCP risks (post-ERCP pancreatitis 3–5%, bleeding, perforation). Reserve ERCP for cholangitis or persistent obstruction.
How do you distinguish gallstone pancreatitis from alcoholic pancreatitis?
Key differentiators: (1) ALT > 150 U/L has ~85% PPV for gallstone etiology. (2) RUQ ultrasound showing gallstones or CBD dilation. (3) History - gallstone pancreatitis often in females, obese, age 40+. Alcoholic pancreatitis in chronic drinkers with recurrent episodes. (4) Gallstone pancreatitis typically has more abrupt onset with biliary-pattern pain (RUQ radiating to back). (5) LFTs: gallstone pancreatitis often shows obstructive pattern (elevated ALP, GGT, direct bili).
What fluid resuscitation strategy is recommended for acute pancreatitis?
Goal-directed moderate IV fluid resuscitation with lactated Ringer's. The WATERFALL trial (2022) showed aggressive fluids (3 mL/kg/hr) increased fluid overload without improving outcomes vs moderate fluids (1.5 mL/kg/hr). Current recommendation: initial bolus of 1.5 mL/kg then maintenance at 1.5 mL/kg/hr, titrated to clinical targets (UOP >= 0.5 mL/kg/hr, HR < 120, MAP > 65). LR preferred over NS (less hyperchloremic acidosis). WATERFALL, 2022
What is the Revised Atlanta Classification for acute pancreatitis severity?
Three severity categories: (1) Mild - no organ failure, no local complications (80% of cases, mortality < 1%). (2) Moderately severe - transient organ failure (< 48h) OR local complications (peripancreatic fluid collection, pseudocyst, walled-off necrosis). (3) Severe - persistent organ failure > 48h (cardiovascular, pulmonary, or renal). Severity determines ICU need, feeding strategy, and cholecystectomy timing. BISAP and APACHE II scores predict severity at admission.
When should you start feeding in acute pancreatitis?
Early oral feeding (within 24h) as tolerated with a low-fat solid diet. Old teaching was NPO until pain resolves and lipase normalizes - this is WRONG. Multiple RCTs show early feeding reduces hospital stay and complications without increasing pain recurrence. No need to wait for lipase normalization. Start with low-fat solid diet (not clear liquids first). If unable to tolerate PO after 72h, consider nasogastric or nasojejunal tube feeding (NOT TPN). Li et al., 2013
What are the indications for antibiotics in acute pancreatitis?
Prophylactic antibiotics are NOT recommended for acute pancreatitis - even in severe/necrotizing disease. The only indications for antibiotics: (1) Confirmed or strongly suspected infected pancreatic necrosis (fever, rising WBC, gas on CT, positive FNA culture). (2) Concurrent cholangitis. (3) Extrapancreatic infections (pneumonia, UTI, line sepsis). For infected necrosis: carbapenems (meropenem 1g IV q8h) have the best pancreatic tissue penetration. AGA Guidelines, 2018
Clinical Examples
📋 Case 1, Mild Gallstone Pancreatitis
Patient: 48F with sudden epigastric pain radiating to back after fatty meal. Lipase 3200, ALT 280, T. bili 2.8, CBD 7 mm on RUQ US with gallstones. HR 92, BP 128/78. No fever.
Key findings: Gallstone pancreatitis (ALT > 150 = ~85% PPV for gallstone etiology). No cholangitis (afebrile, no Charcot triad). Mild disease, no organ failure.
Management:
Goal-directed LR at 1.5 mL/kg/hr × 24h (aggressive hydration within first 24h is key)
Pain control: hydromorphone 0.5 mg IV q3h PRN (no evidence morphine causes sphincter of Oddi spasm)
Early feeding: low-fat solid diet as tolerated (no need to wait for lipase to normalize or pain to resolve)
No ERCP, bilirubin trending down, stone likely passed. No cholangitis. APEC, 2024
Same-admission cholecystectomy within 72h PONCHO, 2015
Teaching point: Old teaching: NPO until pain-free and lipase normalizes. New evidence: early oral feeding is safe and reduces LOS. Don't delay feeding waiting for lab improvement.
📋 Case 2, Severe Necrotizing Pancreatitis
Patient: 55M heavy drinker. Lipase 8400, Cr 2.1, lactate 3.8, HR 118, BP 88/52. CT (72h): > 50% pancreatic necrosis with peripancreatic fluid collections. CRP 340 at 48h.
Key findings: Severe pancreatitis (organ failure + necrosis). BISAP ≥ 3. Alcoholic etiology. High risk for infected necrosis (30-40% of necrotizing pancreatitis).
Management:
ICU admission, aggressive IVF resuscitation (LR), vasopressors if refractory
No prophylactic antibiotics (no mortality benefit in sterile necrosis)
If infected necrosis suspected (gas in collection, clinical deterioration): CT-guided FNA → carbapenems if confirmed
Step-up approach for infected necrosis: percutaneous drain first → if fails, minimally invasive necrosectomy PANTER, 2010
Delay cholecystectomy 4-6 weeks if gallstone etiology (operating in severe inflammation ↑ complications)
Teaching point: The step-up approach (drain → endoscopic/minimally invasive necrosectomy → open surgery) has replaced open necrosectomy as standard of care. ~35% of patients improve with drainage alone.
📋 Case 3, Gallstone Pancreatitis with Cholangitis
Patient: 62F with epigastric pain, lipase 1800, T. bili 6.4 (rising), fever 39.1°C, rigors. WBC 18K. RUQ US: CBD 12 mm, gallstones, no intrahepatic dilation.
Key findings: Charcot triad (fever + jaundice + RUQ pain) = cholangitis. This is the one indication for urgent ERCP in gallstone pancreatitis. Rising bilirubin with fever = impacted stone with biliary sepsis.
Management:
Blood cultures × 2, start piperacillin-tazobactam 4.5g IV q6h (cover GN rods + enterococcus)
Urgent ERCP within 24h for biliary decompression (stone extraction + sphincterotomy)
IVF resuscitation, correct coagulopathy before procedure
If ERCP fails or unavailable: percutaneous transhepatic biliary drain (PTBD)
Same-admission cholecystectomy after cholangitis resolves (prevent recurrence)
Teaching point: Cholangitis is the ONLY absolute indication for ERCP in gallstone pancreatitis. Without cholangitis, most stones pass spontaneously and ERCP adds risk without benefit.
📣 Sample Presentation
One-Liner
"Ms. Garcia is a 45-year-old woman with BMI 34, presenting with epigastric pain radiating to the back, lipase 2800, ALT 320, bilirubin 3.2, RUQ US showing gallstones and CBD 8 mm -gallstone pancreatitis."
Key Points to Cover on Rounds
Gallstone pancreatitis (ALT 320 -high PPV for gallstone etiology). Goal-directed LR. Pain controlled with hydromorphone. Tolerating low-fat diet. Bilirubin trending down (3.2 → 2.1) -stone likely passed, no ERCP needed. No cholangitis. Surgery consulted -plan for same-admission laparoscopic cholecystectomy tomorrow (within 72h of admission per PONCHO). No prophylactic antibiotics. CRP at 48h: 80 (mild disease).
Monitoring
Parameter
Frequency
Target / Action
Lipase
Trending (not daily)
Don't need to normalize before feeding or surgery
LFTs (bilirubin, ALT)
Daily
Improving bilirubin = stone likely passed. Persistently elevated → ERCP.
BMP
Daily
Cr (organ failure), calcium (severity marker)
CRP at 48h
Once at 48h
> 150 = likely severe pancreatitis
CT abdomen
Only if not improving day 3–5
Assess for necrosis, pseudocyst, fluid collections
Surgical consult
Early (same admission)
Cholecystectomy timing -don't discharge without a plan
⚡ Summary
Establish the Etiology
Gallstones cause roughly 40% of acute pancreatitis.An ALT above 150 has about an 85% positive predictive value for a gallstone cause, which is the fastest discriminator available. Confirm with a right upper quadrant ultrasound looking for stones, sludge and duct dilation.
Initial Management Is the Same as Any Pancreatitis
Aggressive but not excessive isotonic fluid, analgesia, and early feeding. Lactated Ringer is preferred over normal saline. Monitor for organ failure in the first 48 h, which is what determines severity, rather than the lipase level, which does not correlate with severity at all.
Feed Early
Start a low-fat solid diet within 24 h as tolerated.Do not wait for pain to resolve or lipase to normalize, and skip the clear liquid ladder: going straight to low-fat solids is safe, shortens the stay and maintains gut barrier function. Nasoenteric feeding for those who cannot eat, not TPN.
Score the Severity Early
BISAP within 24 h: BUN above 25, Impaired mental status, SIRS, Age above 60, Pleural effusion. A score of 3 or more predicts severe disease and guides ICU triage. It is fast, bedside and needs no 48-hour wait, unlike Ranson.
Do Not Scan at Presentation
CT at admission is too early to show necrosis and changes nothing.Get it at 72 to 96 h only if there is no clinical improvement, deterioration despite treatment, or suspicion of a local complication (necrosis, pseudocyst, abscess). Scanning early exposes the patient to contrast and produces a falsely reassuring picture.
ERCP Only for Cholangitis or Persistent Obstruction
Old teaching was ERCP for all gallstone pancreatitis; that is wrong.Indicated for concurrent cholangitis (fever, jaundice, right upper quadrant pain) or persistent biliary obstruction.Most stones have already passed by the time the patient arrives, so routine ERCP in resolving pancreatitis adds a procedural pancreatitis risk for no benefit.
If ERCP Is Done, Give Rectal Indomethacin
Indomethacin 100 mg PR immediately before or after the procedure reduces post-ERCP pancreatitis from roughly 17% to 9% in high-risk patients. It is cheap, single-dose and one of the highest-yield preventive interventions in endoscopy, and it is still frequently omitted.
Cholecystectomy Before Discharge
Do not send a gallstone pancreatitis patient home with the gallbladder in situ.Recurrence is 25 to 30% and the next episode can be the severe one. PONCHO showed same-admission cholecystectomy reduces recurrent biliary events compared with an interval operation. In mild disease, operate during the index admission; in necrotizing pancreatitis, delay about 6 weeks to let the inflammation settle, and consider ERCP with sphincterotomy as the interim protection for a patient who is not a surgical candidate.
pH > 7.45 with elevated HCO₃⁻. Most common acid-base disorder in hospitalized patients. Classify by urine chloride: saline-responsive (UCl < 20) vs saline-resistant (UCl > 20). Replace chloride, not just volume.
🔍 Overview
Pathophysiology
Two requirements: (1) Generation -something creates the alkalosis (vomiting, diuretics, etc.), (2) Maintenance -something prevents the kidney from excreting the excess HCO₃⁻ (volume depletion, Cl⁻ depletion, hypokalemia, mineralocorticoid excess).
Causes, CLEVER PD Mnemonic
C, Contraction alkalosis (volume depletion: diuretics, GI losses, burns)
D, Diuretics (loop, thiazide, both active use and post-diuretic states)
Clinical tip: Most bedside cases come down to Vomiting and Diuretics. If neither fits and BP is elevated → think Endocrine (aldosterone/cortisol excess). If the alkalosis is unexplained and the patient was recently extubated → think Post-hypercapnic.
Classification by Urine Chloride
UCl < 20 (Saline-Responsive)
UCl > 20 (Saline-Resistant)
Vomiting / NGT suction (#1 cause)
Primary hyperaldosteronism
Post-diuretic use (drug cleared / last dose >24h ago)
Current (active) diuretic use
Post-hypercapnic
Cushing syndrome
Chloride-losing diarrhea (rare)
Bartter/Gitelman syndrome
Treatment: NS + KCl
Treatment: Treat underlying cause
💡 Why KCl (not K-phos or K-acetate) in saline-responsive alkalosis?
The chloride in KCl is doing just as much work as the potassium. Here's why the specific salt matters:
Cl⁻ is the "anion companion" the kidney needs to dump HCO₃⁻. The distal tubule (pendrin transporter) exchanges intracellular HCO₃⁻ for luminal Cl⁻. No Cl⁻ delivered → no HCO₃⁻ excreted.
K-acetate and K-citrate are metabolized to HCO₃⁻ in the liver -giving these to an alkalotic patient makes the alkalosis worse.
K-phosphate is fine for K⁺ but provides phosphate, not chloride -doesn't help the kidney excrete bicarbonate.
Hypokalemia itself perpetuates alkalosis via H⁺/K⁺ shift and renal H⁺ wasting → K⁺ must be repleted, and giving it as Cl⁻ fixes two deficits with one order.
Bottom line: NS + KCl works because it replaces both missing anions (Cl⁻) and cations (K⁺) with a form the kidney can use to dump HCO₃⁻. Swapping in K-acetate defeats the treatment.
Causes by Mechanism
Mechanism
Chloride-Responsive (UCl < 20)
Chloride-Resistant (UCl > 20)
GI H⁺ loss
Vomiting, NG suction, villous adenoma (rare)
,
Renal H⁺ loss
Post-diuretic use (drug cleared, last dose >24h ago), post-hypercapnic
Hyperaldosteronism, Cushing, Bartter/Gitelman, licorice ingestion, current (active) diuretic use
HCO₃⁻ gain
Citrate in massive transfusion, milk-alkali syndrome
,
Contraction
Diuretics (volume loss concentrates HCO₃⁻)
,
Intracellular H⁺ shift
Hypokalemia (H⁺ moves into cells as K⁺ moves out)
,
Contraction Alkalosis, Detailed Mechanism
Contraction alkalosis occurs through three synergistic mechanisms: (1) Concentration effect, loss of Cl⁻-rich, HCO₃⁻-poor fluid (e.g., from loop diuretics) concentrates the remaining HCO₃⁻ in a smaller plasma volume. (2) RAAS activation, volume contraction activates the renin-angiotensin-aldosterone system, which increases proximal tubule Na⁺/HCO₃⁻ reabsorption and distal H⁺ secretion. (3) Cl⁻ depletion, without adequate Cl⁻, the kidney cannot excrete HCO₃⁻ (HCO₃⁻ reabsorption in the proximal tubule is linked to Cl⁻ availability). This is why NS (which provides both Na⁺ and Cl⁻) corrects the alkalosis, it expands volume, suppresses RAAS, and provides Cl⁻ for renal HCO₃⁻ excretion.
Clinical pearl, Bartter vs Gitelman:Bartter syndrome mimics chronic loop diuretic use: defective NKCC2 in the thick ascending limb → Na⁺/K⁺/Cl⁻ wasting, metabolic alkalosis, hypokalemia, normal BP. Gitelman syndrome mimics chronic thiazide use: defective NCC in the distal convoluted tubule → same picture as Bartter plushypocalciuria and hypomagnesemia. Both autosomal recessive channelopathies. Distinguish from surreptitious diuretic abuse with a urine diuretic screen.
Timing matters, same drug, two patterns: Diuretics can appear on either side of the table depending on when UCl is sampled. Active/current use (drug still blocking Na/Cl reabsorption) → ongoing urinary Cl wasting → UCl >20 (saline-resistant pattern). Post-diuretic / remote use (drug cleared, typically >24h since last dose) → kidneys resume normal Cl reabsorption, but the alkalosis persists via volume contraction and K⁺/H⁺ depletion → UCl <20 (saline-responsive). Always ask when the last dose was given before interpreting the UCl.
Post-Hypercapnic Alkalosis, Detailed Mechanism
Setup, chronic respiratory acidosis: In chronic CO₂ retention (COPD, obesity hypoventilation, neuromuscular disease, OSA), PaCO₂ stays elevated for days to weeks. The kidneys compensate by retaining HCO₃⁻ (~3.5 mEq/L rise in [HCO₃⁻] per 10 mmHg rise in PaCO₂) so the pH drifts back toward normal. The patient looks like: high PaCO₂, high HCO₃⁻, near-normal pH, a stable compensated respiratory acidosis.
The flip, rapid CO₂ correction: If PaCO₂ is dropped quickly (typically iatrogenic, aggressive mechanical ventilation targeting a "normal" PaCO₂ of 40, or rapid NIV initiation), the compensatory HCO₃⁻ doesn't leave fast enough. The kidneys need 1–2 days to excrete the excess bicarb, but PaCO₂ can be normalized in minutes. Result: pH overshoots → frank metabolic alkalosis unmasked on top of now-normal ventilation.
Why it persists (the "maintenance" problem): These patients are often concurrently volume-depleted (diuretics for cor pulmonale, poor PO intake) and Cl⁻-depleted, so the kidney can't efficiently excrete the retained HCO₃⁻ even once PaCO₂ is normal. The alkalosis sticks around until Cl⁻ and volume are replaced.
Clinical consequences, why this matters: A post-hypercapnic alkalosis can cause respiratory depression (alkalemia suppresses central respiratory drive → hypoventilation → CO₂ re-accumulates → failure to wean from the vent). It can also trigger hypokalemia, hypocalcemia (ionized), seizures, and arrhythmias. Critically, in a ventilated COPD patient it becomes a self-perpetuating weaning failure cycle.
Prevention & treatment:
Don't over-ventilate, target the patient's baseline/home PaCO₂ (often 50–65 mmHg in chronic CO₂ retainers), not 40. Check old ABGs or discharge summaries.
Lower minute ventilation if alkalosis develops (reduce rate or tidal volume) → allow PaCO₂ to rise.
Replace chloride, NS (not LR) gives Na⁺ and Cl⁻; the kidney needs Cl⁻ to excrete HCO₃⁻.
Correct K⁺ and Mg²⁺, hypokalemia perpetuates the alkalosis via distal H⁺ secretion.
Acetazolamide 250–500 mg IV/PO is the pharmacologic option if volume overload prevents saline, induces renal HCO₃⁻ wasting (watch for hypokalemia).
Rarely: HCl infusion via central line for severe pH >7.55 refractory to the above.
Bedside pearl: Before intubating a COPD exacerbation, look at prior ABGs. A patient whose baseline PaCO₂ is 60 and HCO₃⁻ is 32 does not want a PaCO₂ of 40, that will leave them with HCO₃⁻ 32 and PaCO₂ 40 = pH ~7.52 (post-hypercapnic alkalosis by iatrogenesis). "Permissive hypercapnia" in chronic CO₂ retainers isn't just lung-protective, it's also alkalosis-protective.
🚨 Management
Treatment Based on Urine Chloride
Saline-responsive (UCl < 20): IV NS (provides Cl⁻ for kidney to excrete HCO₃⁻) + KCl repletion. Fix the volume and chloride deficit.
Saline-resistant (UCl > 20): Treat underlying cause (e.g., spironolactone for hyperaldosteronism, stop diuretics)
Severe/refractory:Acetazolamide (Diamox) 250–500 mg IV -forces renal HCO₃⁻ wasting
Life-threatening (pH > 7.55): Consider HCl infusion (0.1–0.2 N) via central line, or dialysis
Hypokalemia perpetuates metabolic alkalosis. When K⁺ is low, the kidney reabsorbs K⁺ in exchange for H⁺ secretion → paradoxical aciduria. Replace K⁺ aggressively.
🔑 The 3 C's of Saline-Responsive Alkalosis Repletion
Three deficits maintain a chloride-responsive metabolic alkalosis. You must replace all three -fixing volume alone won't correct it.
Chloride (Cl⁻) -the kidney can only excrete HCO₃⁻ when paired with a reabsorbable anion. Cl⁻ depletion = HCO₃⁻ retention. Give: NS (154 mEq/L Cl⁻).
Contraction (volume) -volume depletion activates RAAS → proximal Na⁺/HCO₃⁻ reabsorption. Until ECF volume is restored, the kidney "clings" to bicarbonate. Give: isotonic crystalloid.
K⁺ (potassium) -hypokalemia drives intracellular H⁺ shift, renal H⁺ secretion, and ammoniagenesis. The alkalosis will not resolve without K⁺ repletion. Give: KCl 10-40 mEq/h (KCl, not K-phos or K-acetate -chloride matters).
Mnemonic:"Chloride, Contraction, K⁺" -or remember that NS + KCl covers all three in one order.
HCl infusion 0.1–0.2 N via central line at 100–200 mL/h. Or: NH₄Cl, or hemodialysis with low-bicarbonate bath.
HCl infusion is caustic, must go through a central line. Calculate Cl⁻ deficit: 0.5 × weight(kg) × (103 – measured Cl⁻). Replace half over 12–24 hours. Monitor ABG q2–4h during infusion.
Why is urine chloride more useful than urine sodium in metabolic alkalosis?
In metabolic alkalosis, the kidney may be "obligated" to excrete Na⁺ with HCO₃⁻ (bicarbonuria) even in volume-depleted states, making urine Na⁺ unreliable. Urine Cl⁻ is not affected by this obligatory loss and accurately reflects volume status. UCl < 20 = volume/Cl⁻ depleted → will respond to saline. UCl > 20 = not volume depleted → look for mineralocorticoid excess.
What is "contraction alkalosis" and how does it occur?
When volume contracts (diuretics, vomiting), the same amount of HCO₃⁻ is dissolved in less plasma volume → concentration effect. Additionally, volume depletion activates RAAS → increased proximal tubule Na⁺/HCO₃⁻ reabsorption → maintenance of alkalosis. The kidney "can't let go" of HCO₃⁻ because it's trying to retain Na⁺ and volume. Giving NS provides Na⁺ and Cl⁻, allowing the kidney to excrete HCO₃⁻.
Why does hypokalemia cause paradoxical aciduria?
When K⁺ is depleted, the kidney's principal cells in the collecting duct reabsorb K⁺ instead of secreting it, and intercalated cells secrete more H⁺ to maintain electroneutrality. This produces acidic urine despite systemic alkalosis -"paradoxical aciduria." It also means the kidney is generating NEW HCO₃⁻, perpetuating the alkalosis. K⁺ must be repleted to correct the alkalosis.
A patient on furosemide has UCl of 35. Does this mean the alkalosis is saline-resistant?
Not necessarily. Current diuretic use is the major exception to the UCl framework. Furosemide blocks the Na-K-2Cl cotransporter in the loop of Henle, causing obligatory Cl⁻ wasting in the urine → UCl > 20 even though the underlying alkalosis IS saline-responsive. The key: if the patient is actively taking diuretics, UCl is unreliable. Stop the diuretic, wait 48–72h, then recheck UCl. Alternatively, treat empirically with NS + KCl and reassess.
How does acetazolamide correct metabolic alkalosis, and what is its main side effect?
Acetazolamide inhibits carbonic anhydrase in the proximal tubule, blocking the conversion of CO₂ + H₂O → H₂CO₃ → H⁺ + HCO₃⁻. This prevents HCO₃⁻ reabsorption, causing renal HCO₃⁻ wasting (bicarbonaturia). Main side effect: hypokalemia, the increased distal Na⁺ delivery drives K⁺ secretion. Always supplement K⁺ when using acetazolamide. Also causes metabolic acidosis if over-used.
What is the expected respiratory compensation for metabolic alkalosis?
The expected PaCO₂ = 0.7 × [HCO₃⁻] + 21 (± 2). The body compensates by hypoventilating to retain CO₂. However, respiratory compensation is limited, PaCO₂ rarely exceeds 55–60 mmHg because hypoxemia from hypoventilation triggers a competing drive to breathe. If PaCO₂ is higher than expected, suspect a concurrent respiratory acidosis (e.g., COPD + vomiting).
How do you differentiate Bartter from Gitelman syndrome?
Both cause metabolic alkalosis with hypokalemia and are saline-resistant (UCl > 20). Bartter = defect in Na-K-2Cl cotransporter (loop of Henle) → mimics loop diuretic. Presents in childhood with polyuria, normal/high urinary calcium, and hypercalciuria. Gitelman = defect in NaCl cotransporter (DCT) → mimics thiazide diuretic. Presents in adolescence/adulthood with milder symptoms, hypocalciuria, and hypomagnesemia.
Why does vomiting cause metabolic alkalosis if the stomach just regenerates the HCl?
When parietal cells secrete H⁺ into the stomach lumen, they generate HCO₃⁻ on the basolateral side (“alkaline tide”). Normally, this HCO₃⁻ is neutralized when pancreatic secretions release HCO₃⁻ into the duodenum to neutralize gastric acid. With vomiting, the H⁺ is lost externally and never reaches the duodenum → the alkaline tide HCO₃⁻ accumulates without being offset.
Clinical Examples
📋 Case 1, Post-Emetic Alkalosis
Patient: 34F with hyperemesis gravidarum at 10 weeks gestation. Vomiting 8–10x/day for 2 weeks. Lethargic, dry mucous membranes. HR 112, BP 88/52. Labs: pH 7.56, PaCO₂ 48, HCO₃⁻ 38, K⁺ 2.6, Cl⁻ 78, Na⁺ 132.
IV NS at 200 mL/h, volume resuscitation + Cl⁻ replacement
KCl 40 mEq in 1L NS x 3, aggressive K⁺ repletion (cannot correct alkalosis without fixing K⁺)
Ondansetron 4 mg IV q8h, antiemetic to stop ongoing losses
Monitor: BMP q6h, urine Cl⁻ at 24h (should rise > 20 once repleted, confirming correction)
Result: After 3L NS + 120 mEq KCl over 24h: pH 7.44, HCO₃⁻ 26, K⁺ 3.8, Cl⁻ 98. Alkalosis corrected.
Key lesson: Classic saline-responsive alkalosis. The triad of vomiting + low UCl + hypokalemia = give NS + KCl aggressively. Must fix K⁺ to fix the alkalosis.
Key lesson: In CHF patients, you cannot just give NS. Acetazolamide is the key tool, it corrects the alkalosis without adding volume. Always pair with K⁺ repletion since acetazolamide causes additional K⁺ wasting.
📋 Case 3, Primary Hyperaldosteronism (Conn Syndrome)
Patient: 52F with resistant hypertension (on 3 agents including amlodipine, losartan, HCTZ). Incidental labs show K⁺ 2.8 and HCO₃⁻ 34. BP 168/102 despite medications. No vomiting, no diarrhea.
Assessment:
Metabolic alkalosis with hypokalemia in the absence of GI losses or diuretics other than HCTZ
Step 1: Morning aldosterone/renin ratio (ARR). Hold HCTZ for 2 weeks, switch losartan to verapamil (does not affect RAAS). Result: aldosterone 28 ng/dL, PRA 0.3 ng/mL/h → ARR = 93 (cutoff > 30).
Step 2: Confirmatory test, oral sodium loading or saline infusion test. Aldosterone fails to suppress → confirmed primary hyperaldosteronism.
Step 3: CT adrenals → 1.8 cm left adrenal adenoma. Adrenal vein sampling confirms lateralization.
Treatment:
Laparoscopic left adrenalectomy, unilateral adenoma with confirmed lateralization
Pre-op: Spironolactone 50 mg BID + KCl supplementation to normalize K⁺ and BP
Post-op: HTN resolved on 1 agent. K⁺ and HCO₃⁻ normalized. Alkalosis corrected.
Key lesson: Resistant HTN + hypokalemia + metabolic alkalosis = think primary hyperaldosteronism (Conn syndrome). It is the most common secondary cause of HTN (5–10% of all HTN). Screen with aldosterone/renin ratio. Saline-resistant alkalosis that does not correct with NS, must treat the underlying cause.
⚡ Summary
It Takes Two Steps
Generation, then maintenance. Something must add bicarbonate or lose acid, and then the kidney must fail to excrete the excess, which it does when volume, chloride or potassium is depleted, or when mineralocorticoid activity is high. Treating only the generating event without fixing the maintenance factor is why the alkalosis persists.
Urine Chloride Splits the Differential
Not urine sodium.UCl below 20 = saline-responsive: vomiting, nasogastric suction, prior diuretic use, contraction alkalosis, post-hypercapnic. UCl above 20 = saline-resistant: primary hyperaldosteronism, Cushing syndrome, active diuretic use, Bartter and Gitelman, severe potassium depletion, licorice. Urine sodium is unreliable here because bicarbonaturia drags sodium out with it even in a volume-depleted patient.
Replace Chloride, Not Just Volume
Chloride is the anion the kidney needs in order to excrete bicarbonate: without it, the collecting duct cannot exchange, so the bicarbonate is retained no matter how much volume is given. Normal saline plus potassium chloride is the treatment for the saline-responsive group. Use KCl, not potassium phosphate or acetate, because acetate is metabolized to bicarbonate and makes the alkalosis worse.
Most Bedside Cases Are Two Things
Vomiting and diuretics. If neither fits and the blood pressure is high, think endocrine, aldosterone or cortisol excess. If it is unexplained and the patient was recently extubated, think post-hypercapnic. CLEVER PD is the fuller list: Contraction, Licorice, Endocrine, Vomiting, Excess alkali, Refeeding, Post-hypercapnia, Diuretics.
The Same Drug Sits on Both Sides
Diuretics give a high urine chloride while the drug is still working and a low one once it has worn off, so the classification depends on when you sampled. Ask when the last dose was given before concluding that a patient is saline-resistant.
Post-Hypercapnic Alkalosis Blocks Weaning
The kidney retained bicarbonate to compensate for chronic CO₂ retention; correcting the CO₂ quickly leaves the bicarbonate behind.The resulting alkalemia suppresses central respiratory drive, so the patient hypoventilates, the CO₂ climbs again and the wean fails. Prevention is not over-ventilating: target the patient's own baseline PaCO₂, often 50 to 65 mmHg in a chronic retainer, not 40. Check an old blood gas or discharge summary.
Fix the Potassium or Nothing Works
Hypokalemia both causes and sustains metabolic alkalosis, by shifting hydrogen ions into cells and stimulating renal ammoniagenesis and bicarbonate reabsorption. Potassium repletion is part of the treatment, not an afterthought, and in severe depletion it is the limiting step.
The Saline-Resistant Group Needs Different Treatment
Saline will not correct these, and volume loading a hyperaldosteronism patient just raises the blood pressure.Mineralocorticoid excess → spironolactone or eplerenone.Ongoing gastric losses → a proton pump inhibitor to reduce acid loss at source.Severe or symptomatic alkalosis with volume overload → acetazolamide, which produces a bicarbonate diuresis but wastes potassium, so replace it. Dialysis for severe alkalosis in renal failure.
Spontaneous bleeding into brain parenchyma. Hypertension is #1 cause. Rapid BP lowering to SBP < 140. Reverse anticoagulation STAT. Hematoma expansion in first 6h drives mortality. Neurosurgery consult for all ICH.
Hematoma expansion occurs in ~30% of ICH patients within the first 6 hours. This is the main driver of early deterioration. Aggressive BP control and anticoagulation reversal are TIME-CRITICAL.
ICH Score (Hemphill, 2001)
Component
Criteria
Points
GCS 3–4
Comatose
2
GCS 5–12
Obtunded / moderate impairment
1
GCS 13–15
Alert / mild impairment
0
ICH volume ≥ 30 mL
Use ABC/2 formula on CT
1
ICH volume < 30 mL
0
IVH present
Intraventricular extension of hemorrhage
1
Infratentorial origin
Cerebellum or brainstem
1
Age ≥ 80
1
ICH Score → 30-day mortality: 0 = 0%, 1 = 13%, 2 = 26%, 3 = 72%, 4 = 97%, 5 = 100%. Caution: Do NOT use as sole basis for withdrawal of care, prognostic nihilism contributes to self-fulfilling prophecies. Early aggressive care is warranted for all patients.
ICH Volume Estimation, ABC/2 Method
On CT, measure: A = largest diameter of hemorrhage (cm), B = diameter perpendicular to A on same slice (cm), C = number of CT slices with hemorrhage × slice thickness (cm). Volume ≈ (A × B × C) / 2 mL.
🚨 Management
Acute Management
BP control: Target SBP < 140 within 1 hour (INTERACT2, 2013). Use Nicardipine (Cardene) or Clevidipine (Cleviprex) drip.
Reverse anticoagulation STAT:
Warfarin → 4-factor PCC (KCentra) + Vitamin K 10 mg IV
Dabigatran → Idarucizumab (Praxbind) 5g IV
Rivaroxaban/Apixaban → Andexanet Alfa (Andexxa) or 4F-PCC
Neurosurgery consult -all ICH. Cerebellar ICH > 3 cm or with hydrocephalus → surgical evacuation
ICP management: HOB 30°, osmotic therapy (mannitol or hypertonic saline), EVD if hydrocephalus
Seizure prophylaxis: NOT routine -treat only clinical seizures. Continuous EEG if altered.
Tranexamic acid (TXA): Consider within 3 hours of injury, especially in mild-to-moderate TBI. CRASH-3, 2019 showed reduced head-injury related death when given early.
BP Management, Key Trials
Trial
Target
Key Finding
INTERACT2, 2013
SBP < 140 mmHg within 1h
Improved functional outcomes (mRS). Safe. Current standard of care.
ATACH-2, 2016
SBP 110–139 vs 140–179
No additional benefit from more aggressive lowering. Increased renal AKI.
Bottom line: Target SBP < 140 within 1 hour (INTERACT2). Do NOT push below 110–120 (ATACH-2 showed harm). Use nicardipine or clevidipine drip with arterial line monitoring.
Anticoagulant Reversal, Emergency Protocol
Anticoagulant
Reversal Agent
Dose
Key Notes
Warfarin
4-factor PCC (KCentra) + Vitamin K
PCC 25–50 units/kg IV + Vit K 10 mg IV
PCC reverses in minutes. Vit K sustains reversal (takes 6–24h). Do NOT use FFP alone (slow, volume overload).
Low dose: 400mg bolus + 4mg/min x 2h; High dose: 800mg bolus + 8mg/min x 2h
Recombinant Xa decoy. ANNEXA-4, 2019. If unavailable, use 4F-PCC 50 units/kg.
Heparin (UFH)
Protamine sulfate
1 mg per 100 units heparin (last 2–3h of infusion)
Max 50 mg. Only partially reverses LMWH (~60%).
Do NOT wait for coagulation studies. If patient is on anticoagulation and has ICH on CT, reverse EMPIRICALLY and immediately. Time to reversal correlates with hematoma expansion and mortality.
Surgical Indications
Cerebellar ICH > 3 cm or with brainstem compression → Surgical evacuation (life-saving, often good outcomes)
Obstructive hydrocephalus → EVD (external ventricular drain) placement, regardless of ICH location
Supratentorial ICH with deterioration: Consider surgery for lobar hemorrhages within 1 cm of cortical surface. STICH II, 2013 showed no broad benefit for early surgery, but consider in deteriorating patients.
Minimally invasive surgery:MISTIE III, 2019, catheter-based clot evacuation showed trend toward benefit if residual clot < 15 mL.
ICP Management
Head of bed 30°, promotes venous drainage, reduces ICP
Osmotic therapy: Mannitol 0.5–1 g/kg IV bolus OR hypertonic saline (23.4% 30 mL via central line, or 3% NaCl 250 mL bolus peripherally)
EVD, both diagnostic (measure ICP) and therapeutic (drain CSF). Target ICP < 20 mmHg, CPP > 60 mmHg
Herniation protocol: If acute pupil dilation or posturing → hyperventilate briefly (target pCO2 30–35), give osmotic bolus, emergent CT and neurosurgery
Seizure Prophylaxis, The Debate
AHA/ASA Guidelines: Routine seizure prophylaxis is NOT recommended. Clinical seizures occur in 8–16% of ICH patients. Subclinical seizures (on EEG) occur in up to 30%. Levetiracetam is preferred if prophylaxis is used; phenytoin is associated with worse outcomes in ICH (Naidech, 2009). Continuous EEG monitoring recommended for patients with GCS decline out of proportion to hemorrhage size.
🧪 Workup
Non-contrast CT head -STAT. Shows hyperdense (white) acute blood. First-line.
CTA head -spot sign (contrast extravasation = active bleeding, predicts expansion)
CBC, PT/INR, PTT, fibrinogen -coagulation status
BMP, glucose
Type and screen
MRI -can evaluate underlying cause (tumor, AVM, cavernoma) once stable
CTA/MRA -evaluate for vascular malformation if non-hypertensive location
💊 Medications
Drug
Dose
Purpose
Nicardipine (Cardene)
5–15 mg/h IV drip
BP control -titratable, no ICP effects
Clevidipine (Cleviprex)
1–21 mg/h IV drip
Ultra-short acting alternative
4-factor PCC (KCentra)
25–50 units/kg IV
Warfarin reversal. Faster than FFP.
Idarucizumab (Praxbind)
5 g IV
Dabigatran reversal. Immediate effect.
Mannitol (Osmitrol)
0.5–1 g/kg IV bolus
ICP reduction -osmotic diuresis
Hypertonic Saline (23.4%)
30 mL IV via central line
ICP crisis -can use via peripheral at lower concentration (3%)
📋 On Rounds
Pimp Questions
What is the ICH Score and what does it predict?
Prognostic score for 30-day mortality: GCS 3-4 (+2), GCS 5-12 (+1), ICH volume ≥ 30 mL (+1), IVH present (+1), Infratentorial (+1), Age ≥ 80 (+1). Score 0 = 0% mortality, Score 5 = 100% mortality. Do NOT use as sole basis for withdrawal of care -prognostic models are imperfect and self-fulfilling prophecies contribute to poor outcomes.
Why is cerebellar hemorrhage a neurosurgical emergency?
The posterior fossa is a tight space. Cerebellar hemorrhage > 3 cm can cause: (1) Brainstem compression → rapid decline, (2) 4th ventricle obstruction → obstructive hydrocephalus, (3) Tonsillar herniation → death. Surgical evacuation is life-saving. EVD for hydrocephalus. These patients can have excellent outcomes with timely intervention -unlike supratentorial ICH.
How do you reverse DOACs in acute ICH?
Dabigatran: Idarucizumab (Praxbind) 5g IV -monoclonal antibody fragment, immediate full reversal. Rivaroxaban/Apixaban (factor Xa inhibitors): Andexanet alfa (Andexxa) -recombinant modified factor Xa decoy. If unavailable, use 4-factor PCC 50 units/kg IV. Key: Do NOT wait for drug levels. Time is brain -reverse empirically if recent DOAC use and ICH confirmed on CT.
What is the BP target in acute ICH and what trials support it?
Target SBP < 140 mmHg within 1 hour, supported by INTERACT2 (2013), which showed improved functional outcomes with intensive lowering. ATACH-2 (2016) tested even more aggressive targets (SBP 110–139) but showed no additional benefit and increased renal injury. Bottom line: aim for SBP < 140, but do not push below 110–120. Use nicardipine or clevidipine drip with an arterial line.
What is the "spot sign" on CTA and why does it matter?
The spot sign is a focus of contrast extravasation within the hematoma seen on CTA. It indicates active, ongoing bleeding and strongly predicts hematoma expansion (positive predictive value ~60–70%). Patients with a spot sign are at higher risk for clinical deterioration and may warrant more aggressive BP management and closer monitoring with repeat imaging.
Why is phenytoin avoided in ICH, and what is the preferred antiepileptic?
Phenytoin use in ICH is associated with worse functional outcomes, more fever, and longer ICU stays (Naidech, 2009). Levetiracetam (Keppra) is preferred if seizure prophylaxis or treatment is needed, it has a better side-effect profile, no drug-drug interactions, and does not require monitoring of drug levels.
How do you calculate ICH volume and why does it matter?
Use the ABC/2 method: A = largest hemorrhage diameter (cm), B = perpendicular diameter on same slice (cm), C = number of slices with hemorrhage x slice thickness (cm). Volume = (A x B x C) / 2 mL. Volume matters because: (1) ICH volume ≥ 30 mL is a component of the ICH Score predicting mortality, (2) volume > 60 mL in supratentorial ICH has ~90% mortality, (3) serial volume assessment detects hematoma expansion (≥33% or ≥6 mL increase).
When would you choose mannitol vs hypertonic saline for ICP management in ICH?
Both are osmotic agents that reduce ICP. Mannitol (0.5–1 g/kg IV): causes osmotic diuresis, avoid in hypotension as it depletes volume. Requires a Foley catheter. Monitor serum osmolality (hold if > 320). Hypertonic saline (HTS): 23.4% (30 mL) via central line or 3% NaCl (250 mL bolus) peripherally, preferred in hypotensive patients as it expands intravascular volume. Target Na 145–155. HTS may be more effective for refractory ICP elevation.
Clinical Examples
📋 Case 1, Hypertensive ICH with BP Management
Patient: 62-year-old male with HTN (non-adherent to meds), presents with sudden severe headache, left hemiparesis, and slurred speech. BP 218/112 on arrival. GCS 12.
CT Head: 25 mL right basal ganglia hemorrhage, no IVH, no hydrocephalus.
Management:
Start nicardipine drip 5 mg/h, titrate to SBP < 140 within 1 hour (INTERACT2 target)
Place arterial line for continuous BP monitoring
Confirm no anticoagulant use → no reversal needed
Neurosurgery consult, supratentorial, non-surgical candidate at this size
Teaching point: Hypertensive basal ganglia hemorrhage is the classic ICH. Rapid BP control to SBP < 140 is the cornerstone of management. Do NOT overshoot below 110 (ATACH-2).
📋 Case 2, Warfarin-Associated ICH with Reversal
Patient: 78-year-old female on warfarin (INR 3.8) for atrial fibrillation. Found by family with confusion and right-sided weakness. BP 176/94. GCS 10.
CT Head: 40 mL left frontoparietal lobar hemorrhage with intraventricular extension.
Management:
4-factor PCC (KCentra) 25–50 units/kg IV STAT, do NOT wait for pharmacy to mix FFP
Vitamin K 10 mg IV, sustains reversal after PCC wears off
Goals of care discussion with family, but do NOT withdraw care based solely on ICH score
Teaching point: Warfarin-associated ICH has the worst outcomes. Time to INR reversal directly impacts hematoma expansion. PCC reverses in minutes vs hours for FFP. Always give vitamin K concurrently for sustained reversal.
📋 Case 3, Cerebellar Hemorrhage Needing Surgery
Patient: 55-year-old male with HTN, presents with sudden occipital headache, vomiting, severe ataxia, unable to stand. BP 198/108. GCS 13 initially, drops to 9 over 30 minutes.
CT Head: 3.5 cm cerebellar hemorrhage with compression of 4th ventricle and early obstructive hydrocephalus.
Management:
EMERGENT neurosurgery consult, this is a surgical emergency
Suboccipital craniectomy and clot evacuation, life-saving for cerebellar ICH > 3 cm with mass effect
EVD placement for obstructive hydrocephalus (caution: draining supratentorial CSF alone can worsen upward herniation)
Nicardipine drip → SBP < 140
HOB 30°, osmotic therapy as bridge to OR
These patients can have excellent functional recovery with timely surgery, unlike supratentorial ICH
Teaching point: Cerebellar ICH is the one ICH where surgery is clearly beneficial. The posterior fossa is a confined space, a 3 cm hemorrhage can cause brainstem compression, obstructive hydrocephalus, and tonsillar herniation within hours. Rapid clinical deterioration (as in this case) demands emergent intervention.
⚡ Summary
The First 6 Hours Decide the Outcome
Hematoma expansion occurs in about 30% of patients within the first 6 hours and is the main driver of early deterioration.Blood pressure control and anticoagulation reversal are time-critical, which means they happen in the scanner corridor, not after admission.
Location Predicts the Cause
Basal ganglia and putamen (the commonest site), thalamus, pons and cerebellum → hypertension.Lobar → cerebral amyloid angiopathy in the elderly, or an underlying lesion.A young patient, an unusual location, or an atypical appearance means look for an AVM, aneurysm, tumor or venous sinus thrombosis with CTA or MRI, rather than assuming hypertension.
Blood Pressure: Low Enough, Not Too Low
Target systolic below 140 within the first hour (INTERACT2). Do not push below 110 to 120: ATACH-2 showed harm from over-aggressive lowering, largely renal. Use a titratable infusion, nicardipine or clevidipine, with an arterial line, since bolus dosing produces the swings that cause the harm.
Reverse Anticoagulation Empirically
If the patient is anticoagulated and has blood on CT, reverse immediately without waiting for coagulation studies.Time to reversal correlates with hematoma expansion and mortality.Warfarin → 4-factor PCC plus vitamin K (PCC over plasma: faster, smaller volume). Dabigatran → idarucizumab.Factor Xa inhibitors → andexanet alfa or PCC.Heparin → protamine.
Score It, But Do Not Let It Decide Care
ICH score maps to 30-day mortality: 0 = 0%, 1 = 13%, 2 = 26%, 3 = 72%, 4 = 97%, 5 = 100%.Do not use it as the sole basis for withdrawing care: prognostic nihilism is self-fulfilling, and early aggressive management improves outcomes in patients whose scores predicted otherwise. Estimate volume with ABC/2 at the bedside.
Know the Surgical Indications
Cerebellar hemorrhage above 3 cm, or with brainstem compression or hydrocephalus, needs urgent evacuation, and this is the one clear-cut surgical indication. An external ventricular drain for hydrocephalus or intraventricular extension.Supratentorial evacuation is not routinely beneficial and is reserved for deteriorating patients or superficial lobar clots. Decompressive craniectomy for refractory intracranial hypertension.
Manage ICP Without Making It Worse
Head of bed at 30 degrees, neck midline, treat pain, fever and agitation, and avoid hypotonic fluids.Hypertonic saline or mannitol for surges, with a target cerebral perfusion pressure of 60 to 70. Avoid prophylactic hyperventilation: it works for minutes by vasoconstriction and then worsens ischemia, so it is a bridge to definitive treatment only.
Do Not Give Prophylactic Antiepileptics
AHA/ASA does not recommend routine seizure prophylaxis. Clinical seizures occur in 8 to 16%, and subclinical seizures on EEG in up to 30%, so treat seizures that happen and get an EEG for unexplained depressed consciousness.If prophylaxis is used, levetiracetam is preferred; phenytoin is associated with worse outcomes. Also: hold anticoagulation, give mechanical VTE prophylaxis from day 1 and start pharmacologic prophylaxis at 48 to 96 h once the hematoma is stable, keep glucose and temperature controlled, and screen swallowing before anything goes by mouth.
RoundsRx Infographic Series · #88 · Neurology · PDF 151 KB
Related Topics
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CommonNeurology
Headache & Migraine
Primary (migraine, tension, cluster) vs secondary (SAH, meningitis, mass, temporal arteritis). Red flags: thunderclap onset, worst ever, focal neuro, fever, papilledema, age > 50 new onset. Triptans for acute migraine.
🔍 Overview
Primary Headache Classification
Type
Features
Duration
Migraine without aura
Unilateral, pulsating, moderate-severe, nausea/vomiting, photophobia/phonophobia, worse with activity
4–72 hours
Migraine with aura
Visual (scintillating scotoma), sensory, or speech aura preceding headache by 5–60 min
4–72 hours
Tension-type
Bilateral, pressing/tightening ("band-like"), mild-moderate, NO nausea/vomiting
30 min–7 days
Cluster
Unilateral orbital/temporal, severe, with autonomic features (lacrimation, rhinorrhea, ptosis, miosis). Male predominance.
15–180 min, occurs in clusters
Red flags (SNOOP):S ystemic (fever, weight loss, cancer, HIV) · N eurologic (focal deficits, papilledema) · O nset sudden (thunderclap → SAH until proven otherwise) · O lder (new onset > 50 → GCA) · P ositional/progressive/precipitated by Valsalva.
Secondary Headache Causes (Do Not Miss)
Diagnosis
Key Features
Workup
Treatment
SAH
Thunderclap onset, "worst headache of life", neck stiffness
First-line. 78% response in 15 min. Cohen et al, JAMA 2009
Acute (abortive)
Sumatriptan 6 mg SC
Second-line. SC only (oral too slow for 15-180 min attacks)
Prophylaxis (first-line)
Verapamil 240-960 mg/day
ECG monitoring (heart block risk at high doses). Takes 1-2 weeks to work
Bridge therapy
Prednisone 60 mg/day x 5d then taper
Rapid relief while verapamil takes effect
Refractory
Lithium, galcanezumab, occipital nerve block
Goadsby et al, NEJM 2019
Dexamethasone for migraine recurrence prevention:Singh & Alter, Acad Emerg Med 2008 A single dose of dexamethasone 10 mg IV in the ED reduces 72-hour migraine recurrence by ~25% (NNT = 9). Should be given with the migraine cocktail, especially for status migrainosus or patients with history of frequent ED visits.
🧪 Workup
When to Image
Thunderclap headache → CT head STAT → if negative, LP for xanthochromia (SAH)
New neurologic deficits → CT/MRI + consider CTA/MRA
New headache age > 50 → ESR, CRP (GCA) + imaging
Positional headache → MRI brain + possible LP (CSF pressure)
Progressive or worsening pattern → MRI with contrast
Typical migraine with normal exam → generally NO imaging needed
💊 Medications
Drug
Dose
Use
Key Notes
Sumatriptan (Imitrex)
50–100mg PO, 6mg SC
Acute migraine
Triptan class -5-HT1B/1D agonist. Avoid in CAD, prior stroke.
Ketorolac (Toradol)
15–30mg IV/IM
Acute migraine (ER)
NSAID. Max 5 days. Renal caution.
Prochlorperazine (Compazine)
10mg IV
Anti-emetic + anti-migraine
Dopamine antagonist. Give with diphenhydramine to prevent EPS.
Thunderclap = maximal intensity within seconds to 1 minute. #1 concern: subarachnoid hemorrhage (SAH). Workup: (1) Non-contrast CT head - sensitivity ~98-100% within 6h, drops to ~50% by day 5. (2) If CT negative, LP - look for xanthochromia (yellow CSF from bilirubin, appears 6-12h after bleed) and elevated RBCs that do NOT clear with successive tubes. (3) If SAH confirmed, CTA or catheter angiography to find the aneurysm. Perry et al, BMJ 2011 Also consider other causes of thunderclap: RCVS, cervical artery dissection, CVT, pituitary apoplexy.
Why are triptans contraindicated in cardiovascular disease?
Triptans are 5-HT1B/1D agonists. The 5-HT1B receptor is found on cranial blood vessels (causing vasoconstriction -the therapeutic effect) but ALSO on coronary arteries. In patients with CAD, triptans can cause coronary vasospasm → myocardial ischemia → MI. Contraindicated in: known CAD, prior MI/stroke/TIA, Prinzmetal angina, uncontrolled HTN, hemiplegic migraine.
What is medication overuse headache and how do you manage it?
MOH = chronic daily headache caused by regular use of acute headache medications. Triptans > 10 days/month, NSAIDs/acetaminophen > 15 days/month. The medication itself perpetuates the headache cycle. Management: (1) Educate the patient, (2) Withdraw the offending medication (can do abruptly for triptans, taper for opioids), (3) Start preventive therapy, (4) Bridge with a short course of steroids or DHE during withdrawal period.
What is the acute treatment for cluster headache?
High-flow oxygen 12-15 L/min via NRB mask x 15 min is first-line (70% response rate within 15 min). Second-line: sumatriptan 6 mg SC (not oral - too slow for cluster). Prophylaxis: verapamil 240-960 mg/day is first-line preventive. Bridge with short course of prednisone while titrating verapamil. Cohen et al, JAMA 2009
What is the sensitivity of CT for SAH over time?
CT sensitivity for SAH declines rapidly with time: within 6 hours: ~98-100%, 12 hours: ~93%, 24 hours: ~90%, 3 days: ~80%, 1 week: ~50%. This is why a negative CT within 6 hours on a modern scanner may be sufficient to rule out SAH without LP in low-risk patients. Perry et al, BMJ 2011 However, the Ottawa SAH Rule and clinical judgment should guide the decision. If CT is done >6h after onset, LP remains necessary.
What are the CGRP monoclonal antibodies and how do they work?
CGRP (calcitonin gene-related peptide) is a key mediator of migraine pathophysiology, released by trigeminal neurons causing vasodilation and neurogenic inflammation. CGRP monoclonal antibodies block this pathway. Erenumab (Aimovig) targets the CGRP receptor; fremanezumab (Ajovy) and galcanezumab (Emgality) target the CGRP ligand. Given monthly SC injection. Reduce migraine days by 50% in ~50% of patients. Few side effects (constipation, injection site reactions). Goadsby et al, NEJM 2017
How do you evaluate for giant cell arteritis (GCA) in a patient >50 with new headache?
GCA is a medical emergency because of risk of irreversible vision loss. Workup: (1) ESR (typically >50, often >100) and CRP (elevated). (2) Temporal artery biopsy is the gold standard (skip lesions can cause false negatives, so biopsy >2 cm). (3) Start prednisone 60 mg/day immediately - do NOT wait for biopsy results. Biopsy remains positive for 1-2 weeks after steroid initiation. (4) If vision symptoms present, admit for IV methylprednisolone 1g x 3 days. Proven et al, Neurology 2009
What is the "migraine cocktail" and why does it work?
The ED migraine cocktail targets multiple pathways: (1) Ketorolac 30 mg IV - NSAID, anti-inflammatory + analgesic. (2) Prochlorperazine 10 mg IV (or metoclopramide) - dopamine antagonist, anti-emetic + direct anti-migraine effect via dopamine pathway blockade. (3) Diphenhydramine 25 mg IV - prevents akathisia/EPS from prochlorperazine + mild sedation. Some protocols add IV fluids (dehydration is a trigger) and magnesium 2g IV (reduces cortical spreading depression). Friedman et al, Ann Emerg Med 2008
When should you start migraine prophylaxis?
Start prophylaxis when: (1) >=4 headache days per month. (2) Attacks are severe and disabling despite acute treatment. (3) Acute medication use >=2 days/week (risk of MOH). (4) Patient preference. (5) Contraindication to acute therapies. First-line options: topiramate (best evidence), propranolol, amitriptyline. CGRP antibodies for patients who fail 2+ oral preventives. Give any preventive an adequate trial of 2-3 months before declaring failure. Silberstein et al, Neurology 2012
Clinical Examples
📋 Case 1 - Thunderclap Headache: SAH Workup
Patient: 48F presents with "worst headache of my life" that reached peak intensity within 30 seconds while exercising. Associated with nausea and neck stiffness. No prior headache history. Exam: GCS 15, mild photophobia, no focal deficits.
Workup: Non-contrast CT head (within 2 hours of onset): negative for hemorrhage. Given early presentation, CT has ~98-100% sensitivity. Decision made to proceed with LP given high clinical suspicion.
LP results: Tube 1: 850 RBCs. Tube 4: 780 RBCs (no clearing). Xanthochromia positive by spectrophotometry.
Assessment: SAH with negative CT but positive LP (xanthochromia + non-clearing RBCs). Approximately 2-5% of SAH cases are CT-negative.
Management: CTA head: 4 mm anterior communicating artery aneurysm. Neurosurgery consulted. Endovascular coiling performed. Nimodipine 60 mg PO q4h for vasospasm prevention x 21 days. ICU monitoring with daily TCDs. Good outcome.
📋 Case 2 - Status Migrainosus in the ED
Patient: 32F with known migraines (6/month) presents with severe throbbing left-sided headache x 4 days that has not responded to home sumatriptan (used 3 doses) or ibuprofen. Nausea, vomiting, photophobia. Unable to work or sleep.
Exam: VS stable. Neurologic exam normal. No papilledema. No meningismus.
Assessment: Status migrainosus (migraine lasting >72 hours). Also using triptans >10 days/month, raising concern for medication overuse headache.
Management: Migraine cocktail: ketorolac 30 mg IV + prochlorperazine 10 mg IV + diphenhydramine 25 mg IV + 1L NS. Added dexamethasone 10 mg IV (reduces 72h recurrence by 25%). Pain improved 2h later. Discharged with: referral to headache specialist, topiramate 25 mg daily (prophylaxis), instructions to limit triptan use to <=2 days/week.
📋 Case 3 - New Headache in Elderly: Giant Cell Arteritis
Patient: 72F with new-onset right temporal headache x 2 weeks, worse with chewing (jaw claudication). Also reports 10 lb weight loss and shoulder stiffness. No headache history.
Exam: Tender, non-pulsatile right temporal artery. Visual acuity 20/20 bilaterally (no vision loss yet). Fundoscopic exam normal.
Assessment: Giant cell arteritis (GCA). New headache age >50 + jaw claudication + markedly elevated ESR/CRP. High risk for irreversible vision loss if untreated.
Management: Started prednisone 60 mg/day immediately (do NOT wait for biopsy). Temporal artery biopsy scheduled within 1 week (remains positive up to 2 weeks after steroids). Ophthalmology consulted for baseline exam. Biopsy returned: granulomatous arteritis with giant cells. Slow steroid taper over 12-18 months guided by symptoms and ESR/CRP. Added PPI + calcium/vitamin D + DEXA scan for steroid bone protection.
⚡ Summary
Sort Primary From Secondary First
Primary: migraine, tension-type, cluster.Secondary is what kills: subarachnoid hemorrhage, meningitis, mass lesion, giant cell arteritis, venous sinus thrombosis, idiopathic intracranial hypertension, carbon monoxide. The history does most of this work, and imaging is directed by red flags rather than by severity.
SNOOP Red Flags
Systemic (fever, weight loss, cancer, HIV, immunosuppression) · Neurologic (focal deficit, papilledema, altered consciousness) · Onset sudden · Older, new onset over 50 · Pattern change or positional, or worsening with Valsalva. Any one of these means image before treating.
Thunderclap Means Subarachnoid Until Proven Otherwise
Maximal intensity within seconds, the worst headache of life.Non-contrast CT is about 98% sensitive within 6 h of onset and falls off after that, so a negative CT beyond that window needs a lumbar puncture for xanthochromia. Also consider cervical artery dissection, venous sinus thrombosis and reversible cerebral vasoconstriction syndrome in the same presentation.
New Headache Over 50 Means Check for GCA
ESR and CRP, and ask about jaw claudication, scalp tenderness, visual symptoms and polymyalgia.Start high-dose steroids immediately on clinical suspicion; do not wait for the temporal artery biopsy, which stays positive for weeks after treatment starts. The vision loss is irreversible and can be bilateral within days.
Acute Migraine: Treat Early and With Combinations
Triptans work best given early in the attack, before central sensitization sets in, which is why waiting to see if it passes makes the treatment less effective. Contraindicated in coronary and cerebrovascular disease and in hemiplegic or basilar migraine. In the emergency department, an antidopaminergic (metoclopramide or prochlorperazine) plus IV fluids plus an NSAID outperforms opioids. Give diphenhydramine with the antidopaminergic to prevent akathisia and dystonia.
Add Dexamethasone Before Discharge
A single 10 mg IV dose reduces 72-hour migraine recurrence by roughly 25%, NNT 9. It does nothing for the headache in front of you, so give it alongside the abortive rather than instead of it. Avoid opioids and butalbital entirely: they cause medication-overuse headache and worsen the long-term pattern.
Prophylaxis at 4 or More Headache Days a Month
Choose the agent by comorbidity: propranolol or metoprolol (avoid in asthma and depression), topiramate (weight loss, but teratogenic and causes cognitive slowing), amitriptyline (helps with insomnia and coexisting tension headache), valproate (never in a person who could become pregnant), and CGRP monoclonal antibodies for refractory disease. Give any agent an 8 to 12 week trial at an adequate dose before calling it a failure.
Cluster Headache Has Its Own Treatment
Severe unilateral orbital or temporal pain lasting 15 to 180 min with ipsilateral autonomic features, in a patient who paces rather than lies still. Abort with high-flow oxygen 12 to 15 L/min by non-rebreather plus subcutaneous sumatriptan; oral triptans are too slow for an attack this short. Verapamil is the prophylactic of choice, with a steroid taper as a bridge while it takes effect, and ECG monitoring as the dose rises.
RoundsRx Infographic Series · #132 · Neurology · PDF 153 KB
Related Topics
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EmergentNeurology
Spinal Cord Compression
Oncologic emergency. Back pain → radiculopathy → weakness → sensory level → bowel/bladder dysfunction. MRI STAT. Dexamethasone 10mg IV immediately. Neurosurgery + radiation oncology within hours. Time to treatment determines outcome.
🔍 Overview
Etiology
Cause
Details
Metastatic disease
#1 cause. Lung, breast, prostate, RCC, myeloma. Usually epidural (vertebral body mets → posterior extension)
Primary spine tumors
Meningioma, schwannoma, ependymoma
Epidural abscess
Fever + back pain + risk factors (IVDU, recent spinal procedure). S. aureus #1.
Epidural hematoma
Post-procedure or anticoagulation
Disc herniation
Most common cause of non-malignant cord compression
ANY cancer patient with new back pain must have spinal cord compression excluded. Once motor deficits appear, the window for meaningful recovery is hours. Ambulatory status at diagnosis is the #1 predictor of outcome.
🚨 Management
Emergent Management
Dexamethasone 10 mg IV STAT then 4 mg IV q6h -reduces vasogenic edema around cord
MRI entire spine with contrast -STAT. Multiple levels in 30% of cases.
Neurosurgery consult -surgical decompression if: single level, good functional status, life expectancy > 3 months, radioresistant tumor
Radiation oncology consult -definitive treatment for most metastatic SCC. Start within 24h.
Patchell trial (2005): Surgery followed by radiation was superior to radiation alone for ambulatory recovery (84% vs 57%) in patients with single-level metastatic SCC and reasonable prognosis.
🧪 Workup
MRI entire spine with gadolinium -gold standard. Must image ENTIRE spine (multiple lesions in 30%)
CT myelogram -if MRI contraindicated (pacemaker)
Plain films -vertebral body collapse, but misses early compression
Post-void residual -bladder dysfunction is late sign
💊 Medications
Drug
Dose
Purpose
Dexamethasone (Decadron)
10 mg IV bolus → 4 mg IV q6h
Reduce cord edema. Start immediately on clinical suspicion.
Oxycodone (OxyContin)
5–15 mg PO q4–6h
Pain control. Often severe.
Gabapentin (Neurontin)
300–900 mg TID
Neuropathic pain adjunct
Omeprazole (Prilosec)
20–40 mg daily
GI prophylaxis with high-dose steroids
📋 On Rounds
Pimp Questions
What is the clinical progression of spinal cord compression?
Back pain (earliest, present in 95%) → radiculopathy (dermatomal pain) → motor weakness (UMN pattern: spasticity, hyperreflexia below level) → sensory level → bowel/bladder dysfunction (latest -if present, prognosis for recovery is poor). Ambulatory status at presentation is the #1 predictor of outcome. Once paraplegia develops, only 10% regain ambulation.
Why must you image the ENTIRE spine in suspected SCC?
30% of patients with metastatic SCC have disease at multiple spinal levels. Imaging only the symptomatic level may miss additional lesions that could cause future compression or be targeted with radiation. Additionally, a symptomatic thoracic lesion may have additional cervical involvement that changes surgical planning. Always order MRI of the entire spine with gadolinium contrast.
What is cauda equina syndrome and how does it differ from cord compression?
Cauda equina syndrome affects the nerve roots below the conus medullaris (L1-L2), producing LMN signs: flaccid weakness, areflexia, saddle anesthesia, and early bowel/bladder dysfunction (urinary retention → overflow incontinence). Cord compression above this level produces UMN signs: spastic weakness, hyperreflexia, Babinski sign. Both are surgical emergencies, but the clinical picture differs.
Clinical Examples
📋 Case 1, Metastatic Spinal Cord Compression
Patient: 67M with known metastatic prostate cancer. Progressive mid-back pain × 3 weeks, now unable to walk since yesterday. Bilateral LE weakness (3/5), hyperreflexia, upgoing toes. Urinary retention (600 mL on bladder scan).
Key findings: UMN signs (hyperreflexia, Babinski) + sensory level at T8 + bladder dysfunction = thoracic spinal cord compression. Metastatic prostate cancer is the #1 cause of malignant cord compression.
Management:
Dexamethasone 10 mg IV STAT → 4 mg IV q6h (reduces vasogenic edema around the cord)
Emergent MRI entire spine with contrast (30% have multiple levels of compression)
Neurosurgery consult for decompressive surgery if single level, good prognosis, and not radiosensitive Patchell, 2005
Radiation oncology consult, XRT alone if radiosensitive tumor (lymphoma, myeloma, SCLC) or poor surgical candidate
Foley catheter for urinary retention; bowel regimen
Teaching point: Ambulatory status at diagnosis is the #1 predictor of outcome. Patients who can still walk at presentation have ~80% chance of maintaining ambulation. Once paralyzed > 48h, recovery is rare. Speed matters, dexamethasone and MRI are both emergent.
📋 Case 2, Cauda Equina Syndrome from Disc Herniation
Patient: 42F with acute low back pain after heavy lifting, now with bilateral leg weakness, saddle numbness, and inability to urinate × 12 hours. Exam: flaccid bilateral LE weakness, absent ankle reflexes, decreased perianal sensation, lax anal tone.
Key findings: LMN signs (flaccid weakness, areflexia) + saddle anesthesia + urinary retention = cauda equina syndrome. Disc herniation at L4-L5 or L5-S1 is the most common cause in young adults.
Management:
Emergent MRI lumbar spine, do not delay for any reason
Neurosurgery consult for emergent decompressive laminectomy (within 24-48h of symptom onset for best outcomes)
Foley catheter for urinary retention
Pain management: avoid opioids if possible pre-surgery; ketorolac 15 mg IV
Post-op: bladder function recovery may take weeks-months; monitor post-void residuals
Teaching point: Cauda equina syndrome is a surgical emergency with a narrow treatment window. Decompression within 48 hours of urinary retention onset gives the best chance of bladder recovery. After 48h, permanent deficits are common.
📋 Case 3, Epidural Abscess Mimicking Cord Compression
Patient: 55M IVDU with 5 days of progressive back pain, fever (39.2°C), and now bilateral LE weakness. WBC 22K, ESR 110, blood cultures positive for MSSA. MRI: epidural abscess T10-T12 with cord compression.
Key findings: Spinal epidural abscess, classic triad: back pain + fever + neurologic deficits. IVDU is the #1 risk factor. S. aureus is the #1 organism. Hematogenous spread from bacteremia.
Vancomycin 25-30 mg/kg IV load + cefepime 2g IV q8h (empiric until culture-directed, cover MRSA + GNRs)
Narrow to nafcillin/oxacillin once MSSA confirmed (6-8 weeks IV antibiotics)
Serial MRI to monitor abscess resolution
Echo to rule out endocarditis (IVDU + S. aureus bacteremia = 30% concomitant endocarditis)
Teaching point: The classic triad of epidural abscess (back pain + fever + neuro deficits) is only present in 10-15% at initial presentation. Back pain + fever in IVDU → MRI the spine. Once motor deficits develop, surgery must happen within hours to prevent permanent paralysis.
⚡ Summary
Back Pain Is the Warning
The sequence is back pain, then radiculopathy, then weakness, then a sensory level, then bowel and bladder dysfunction.Any cancer patient with new back pain must have cord compression excluded.Pain precedes deficit by weeks, and that is the only window in which the outcome is fully preventable.
Ambulatory Status Is the Whole Prognosis
Function at the time treatment starts is the single strongest predictor of function afterward.Once motor deficits appear the window for meaningful recovery is hours, not days. A patient who is still walking is an emergency precisely because they can stay that way.
Dexamethasone Immediately
10 mg IV bolus, then 4 mg q6h, before the imaging returns. It reduces vasogenic edema around the lesion and buys time. Do not wait for the MRI report to give it: the drug is safe, the delay is not.
MRI of the Whole Spine, Not the Painful Level
Multilevel disease is common and changes the radiation field. Imaging only the symptomatic level misses synchronous lesions that will present a month later. CT myelography if MRI is contraindicated.
Call Both Services Within Hours
Neurosurgery and radiation oncology together.Surgery followed by radiation beats radiation alone for a single site with spinal instability, bony retropulsion, or a radioresistant tumor, and it is what preserves ambulation (Patchell). Radiation alone for multilevel disease, a radiosensitive tumor such as lymphoma or myeloma, a poor surgical candidate, or a short life expectancy.
Know the Non-Malignant Causes
Metastatic disease is number one (lung, breast, prostate, renal cell, myeloma), usually epidural from a vertebral body. Epidural abscess: fever plus back pain plus a risk factor (injection drug use, recent spinal procedure, bacteremia), most often S. aureus, needing drainage and antibiotics rather than steroids. Epidural hematoma after a procedure or on anticoagulation.Disc herniation is the commonest non-malignant cause.
Cauda Equina Is the Same Urgency
Saddle anesthesia, urinary retention with overflow incontinence, bilateral leg weakness and loss of anal tone.Check a post-void residual: retention is the most reliable early objective sign, and it is easy to obtain at the bedside. This needs emergent decompression, not next-day imaging.
Get Tissue if the Cancer Is Not Known
Cord compression can be the presenting event of an unknown malignancy, and steroids can render a lymphoma unbiopsiable. If lymphoma is plausible and the patient is neurologically stable, obtain tissue first. Otherwise treat, then biopsy. Also start VTE prophylaxis, manage the pain properly, and arrange rehabilitation early, since function recovers over weeks.
Foley -urine output monitoring (do NOT place if blood at meatus, high-riding prostate, scrotal hematoma)
NGT/OGT -decompress stomach. OGT if midface fracture suspected.
Secondary Survey
Head-to-toe exam AFTER primary survey and stabilization. "Fingers and tubes in every orifice." Log roll to examine spine. Complete neuro exam. Document all injuries.
Key Evidence: Balanced resuscitation with 1:1:1 ratio reduces 24h mortality from exsanguination PROPPR, 2015. TXA within 3 hours of injury reduces all-cause mortality CRASH-2, 2010. Whole blood resuscitation may be superior to component therapy PILOT, 2022. Permissive hypotension (SBP 80-90) in penetrating trauma reduced mortality vs aggressive resuscitation Bickell, 1994.
Paralytic for RSI -longer duration but sugammadex reversible
Norepinephrine (Levophed)
0.1–0.5 mcg/kg/min
Vasopressor -AFTER volume resuscitation, not as substitute
📋 On Rounds
Pimp Questions
When is a FAST exam unreliable?
FAST detects free fluid (≥ 200 mL) but cannot identify retroperitoneal bleeding (renal, vascular, pelvic fractures), hollow viscus injury, or diaphragmatic injury. Sensitivity is operator-dependent (~85–96% for hemoperitoneum). A negative FAST does NOT rule out intra-abdominal injury -if clinical suspicion remains high, proceed with CT.
Why do you NOT place a Foley if there is blood at the urethral meatus?
Blood at the meatus, high-riding prostate on DRE, or scrotal/perineal hematoma suggest urethral injury. Blindly inserting a Foley could convert a partial urethral tear into a complete transection. Get a retrograde urethrogram (RUG) first. If positive, urology places a suprapubic catheter instead.
What is the "lethal diamond" in trauma?
Extension of the lethal triad: hypothermia + acidosis + coagulopathy + hypocalcemia (from massive transfusion). Citrate in blood products chelates calcium → cardiac dysfunction. The damage control resuscitation approach addresses all four: warm products, limit crystalloid (worsens acidosis), 1:1:1 ratio, and replace calcium (1g CaCl per 4 units pRBC).
What is damage control resuscitation?
Limit crystalloid (worsens acidosis/coagulopathy), use 1:1:1 blood products, permissive hypotension (target SBP 80-90 until surgical hemostasis), and damage control surgery (abbreviated laparotomy, pack and close, ICU resuscitate, return to OR). Holcomb JAMA Surg, 2015.
What are indications for emergent thoracotomy in trauma?
Penetrating thoracic trauma with loss of vital signs in ED or en route (within ~15 min). >1500 mL initial chest tube output or >200 mL/hr ongoing. Cardiac tamponade. Survival is ~35% for stab wounds but <5% for blunt trauma. EAST Guidelines, 2015.
What is the MARCH mnemonic for tactical trauma?
M = Massive hemorrhage (tourniquet), A = Airway, R = Respiration (needle decompress, chest seal), C = Circulation (IV access, TXA, blood products), H = Hypothermia prevention. Prioritizes hemorrhage control before airway, unlike traditional ABCDE.
When do you activate massive transfusion protocol (MTP)?
ABC score ≥ 2 (penetrating mechanism, SBP ≤ 90, HR ≥ 120, positive FAST). Also: estimated blood loss > 1500 mL, anticipated need for > 10 units pRBC in 24h, hemodynamic instability despite 2L crystalloid. Cotton, 2009.
What is the difference between primary and secondary brain injury in TBI?
Primary = mechanical damage at time of impact (contusion, diffuse axonal injury, epidural/subdural hematoma). Cannot be reversed. Secondary = preventable cascade: hypotension, hypoxia, hyperthermia, hyperglycemia, seizures. A single episode of SBP < 90 doubles mortality. Focus is preventing secondary injury.
What is permissive hypotension and when is it contraindicated?
Target SBP 80-90 in hemorrhagic shock to minimize ongoing bleeding until surgical control. Reduces dilutional coagulopathy from excess crystalloid. Contraindicated in TBI (need SBP > 100 for cerebral perfusion) and spinal cord injury. Bickell, 1994.
Clinical Examples
📋 Case 1, Blunt Polytrauma with Hemorrhagic Shock
Patient: 28M MVC unrestrained driver, GCS 13 (E3V4M6). HR 132, BP 78/42, RR 28. Distended abdomen, pelvic instability on exam. FAST positive (Morrison's pouch).
Key findings: Class IV hemorrhagic shock (tachycardic, hypotensive, AMS). FAST positive = intra-abdominal hemorrhage. Unstable pelvis = likely pelvic fracture with venous plexus bleeding.
Pelvic binder immediately (reduces venous bleeding volume by ~50%)
TXA 1g IV over 10 min → 1g over 8h (must give within 3h of injury) CRASH-2, 2010
Permissive hypotension: target SBP 80-90 until surgical control
OR for exploratory laparotomy, damage control surgery
Teaching point: In penetrating/blunt trauma with hemorrhagic shock, the ED goal is stop the bleeding, not normalize vitals with crystalloid. Crystalloid worsens coagulopathy, hypothermia, and acidosis.
📋 Case 2, Tension Pneumothorax
Patient: 35F stab wound to left chest. Initially stable, now HR 140, BP 62/40, SpO₂ 82%. Absent breath sounds on left. Tracheal deviation to the right. JVD.
Key findings: Classic tension pneumothorax: hypotension + absent breath sounds + tracheal deviation + JVD. This is a clinical diagnosis, do NOT wait for CXR.
Management:
Needle decompression IMMEDIATELY, 14g angiocath, 2nd intercostal space midclavicular line (or 5th ICS anterior axillary)
Follow with tube thoracostomy (chest tube 28-32 Fr) in left 5th ICS anterior axillary line
Reassess: expect rapid improvement in BP and SpO₂ after decompression
If persistent hemorrhage (> 1500 mL initial output or > 200 mL/hr) → thoracotomy
Serial CXR to confirm lung re-expansion
Teaching point: Tension pneumothorax is a clinical diagnosis treated before imaging. The classic triad (hypotension, absent breath sounds, tracheal deviation) may not all be present, decompress based on high clinical suspicion.
📋 Case 3, Traumatic Brain Injury
Patient: 55M fall from ladder, GCS 7 (E1V2M4). Right pupil 6 mm fixed. Left-sided hemiplegia. HR 58, BP 190/100. CT: right-sided epidural hematoma with 8 mm midline shift.
Intubate for airway protection (GCS ≤ 8), avoid hypotension during RSI
Mannitol 1 g/kg IV or hypertonic saline 23.4% 30 mL IV push (temporizing for herniation)
Emergent neurosurgery consult for craniotomy and evacuation
Target SBP > 100 (avoid hypotension, single episode doubles mortality in TBI)
Head of bed 30°, avoid hyperthermia, maintain PaCO₂ 35-40 mmHg
Teaching point: In TBI, the secondary injury (hypotension, hypoxia, hyperthermia) is preventable. Maintaining SBP > 100 and SpO₂ > 90% is the single most impactful intervention for TBI outcomes.
⚡ Summary
ABCDE, in Order, Every Time
Airway with C-spine control, Breathing, Circulation, Disability, Exposure.The order exists because it treats in the sequence that kills fastest, and you do not move on until the current step is fixed. Any deterioration means going back to A and starting again.
A and B: What Kills in the First Minutes
Airway: can they speak? Stridor, facial or neck trauma, expanding hematoma → jaw thrust with in-line stabilization, suction, then a definitive airway.Breathing: tension pneumothorax is a clinical diagnosis and is decompressed before any x-ray, along with open pneumothorax (three-sided seal), massive hemothorax and flail chest with contusion.
C: Find the Blood
Bleeding hides in five places: the chest, the abdomen, the pelvis or retroperitoneum, the long bones, and the floor (external).Two large-bore IVs, direct pressure and tourniquets, a pelvic binder for an unstable pelvis, and activate massive transfusion early.Give blood, not crystalloid, and TXA within 3 hours (CRASH-2), which increases mortality if given later.
Class of Hemorrhagic Shock, and Its Trap
Class I up to 15% loss, normal vitals. Class II 15 to 30%, tachycardia and a narrowed pulse pressure. Class III 30 to 40%, hypotension and confusion. Class IV above 40%, moribund.A narrowing pulse pressure precedes hypotension, and young patients compensate until they crash. Beta blockade, pacing, pregnancy and the elderly all blunt the tachycardia, so a normal heart rate never excludes shock.
D: Report GCS in Components
Severe TBI is GCS 3 to 8 and means intubate. Moderate 9 to 12, mild 13 to 15.Always report the components, E3V4M6, not just the total: the motor score carries most of the prognostic weight, and two patients with the same total can be very different. Check pupils and look for herniation, treating with head-up positioning and hypertonic saline or mannitol.
E: Exposure Without Hypothermia
Fully undress, log roll and inspect the back, axillae, perineum and scalp, which is where penetrating wounds get missed. Then cover and warm immediately: hypothermia is one third of the lethal triad, and clotting enzymes fail before the patient feels cold to you.
Adjuncts Belong to the Primary Survey
FAST, chest x-ray and pelvic x-ray, plus ECG, blood gas, type and cross.A positive FAST in an unstable patient goes to the operating room, not the CT scanner.A negative FAST does not exclude injury: it misses retroperitoneal bleeding and most solid organ injury without free fluid, so a stable patient with a concerning mechanism still gets a CT.
Secondary Survey and Damage Control
Head-to-toe examination with AMPLE history (allergies, medications, past history, last meal, events) only after the patient is stabilized. Damage control surgery stops bleeding and contamination, then leaves the abdomen open for ICU correction of the lethal triad and delayed definitive repair, because a hypothermic, acidotic, coagulopathic patient does not survive a long definitive operation.
Sudden onset abdominal pain requiring urgent evaluation. Surgical vs medical cause is the critical distinction. CT is the workhorse imaging. Pain out of proportion to exam = mesenteric ischemia or vascular emergency.
Cannot-miss diagnoses: AAA rupture, mesenteric ischemia (pain out of proportion), ectopic pregnancy (all women of childbearing age get β-hCG), testicular/ovarian torsion, perforated viscus.
Do NOT withhold pain medication while awaiting surgical evaluation. The old teaching that analgesics "mask" peritoneal signs and delay diagnosis is disproven. Pain control improves the physical exam by allowing the patient to cooperate Thomas, 2003. Give morphine 0.1 mg/kg IV while workup proceeds.
Pain control -Morphine (MS Contin) or Fentanyl (Sublimaze). Treating pain does NOT mask surgical findings.
NPO -if surgical cause suspected
Surgery consult -peritonitis, free air, hemodynamic instability
Surgical Emergencies (Cannot Wait)
Perforated viscus (free air under diaphragm)
AAA rupture
Mesenteric ischemia with infarction
Strangulated hernia/SBO
Testicular/ovarian torsion
Ectopic pregnancy with hemodynamic instability
Surgical vs Medical Acute Abdomen: Surgical emergencies requiring OR: perforated viscus (free air on CT), mesenteric ischemia with bowel necrosis, ruptured AAA, appendicitis, incarcerated hernia. Medical causes to consider: DKA (can mimic surgical abdomen), pancreatitis (usually medical), inferior MI (epigastric pain), adrenal crisis, sickle cell crisis, porphyria, C. diff colitis.
Antibiotics-first for uncomplicated appendicitis? The CODA 2020 trial showed antibiotics alone were noninferior to surgery for uncomplicated appendicitis at 30 days, but 29% eventually needed appendectomy within 90 days CODA, 2020. Surgery remains standard of care, but antibiotics-first is a shared decision option in select patients.
🧪 Workup
CT abdomen/pelvis with IV contrast -workhorse imaging for acute abdomen ACR Appropriateness Criteria, 2018
Upright CXR -free air under diaphragm (perforated viscus)
US -RUQ (biliary), pelvic (OB/GYN pathology), bedside FAST
CBC, BMP, lipase, LFTs, lactate, UA
β-hCG -ALL women of childbearing age. Ectopic kills.
Type & screen if surgical candidate
Key Evidence: CT abdomen/pelvis with IV contrast is the most sensitive single test for acute abdomen (sensitivity > 95% for most surgical emergencies) Rosen, 2000. For suspected appendicitis, CT has 94% sensitivity and 95% specificity Doria, 2006. Ultrasound is first-line for biliary disease (sensitivity 95% for gallstones) and in pregnancy. MRI appendicitis protocol is safe and accurate in pregnancy Duke, 2016.
💊 Medications
Drug
Dose
Purpose
Morphine (MS Contin)
2–4 mg IV q2–4h
Pain control -does NOT mask surgical exam
Ketorolac (Toradol)
15–30 mg IV
NSAID -good for renal colic, biliary colic
Ondansetron (Zofran)
4 mg IV
Anti-emetic
Piperacillin-Tazobactam (Zosyn)
3.375 g IV q6h
Broad-spectrum if peritonitis/perforation
IV NS/LR
Bolus 1–2 L
Volume resuscitation
Clinical Examples
📋 Case 1, Perforated Peptic Ulcer
Patient: 55-year-old man with chronic NSAID use presents with sudden-onset severe epigastric pain radiating to the right shoulder (Kehr sign). Rigid abdomen, rebound tenderness, absent bowel sounds.
Key findings: Upright CXR shows free air under right hemidiaphragm. Lactate 3.2, WBC 18K. Tachycardic, BP 95/60.
Management:
NPO, IV fluids, broad-spectrum antibiotics (piperacillin-tazobactam)
Emergent surgery consult for exploratory laparotomy and repair
Pain control with IV fentanyl (does NOT mask surgical exam)
Teaching point: Free air under the diaphragm = perforated viscus until proven otherwise. This is a surgical emergency - surgical repair within 24 hours is associated with decreased mortality Soreide et al., 2015. Do not delay for CT if clinical picture is clear and patient is unstable.
📋 Case 2, Acute Mesenteric Ischemia
Patient: 72-year-old woman with atrial fibrillation (not on anticoagulation) presents with severe periumbilical pain for 6 hours. Pain is 10/10 but abdomen is soft and non-tender on palpation.
Key findings: Pain out of proportion to exam. Lactate 5.8. WBC 22K. CT angiography shows SMA thromboembolism with bowel wall thickening.
Management:
Emergent vascular surgery consult for embolectomy vs endovascular intervention
IV heparin anticoagulation
Aggressive IV fluid resuscitation, broad-spectrum antibiotics
If peritonitis develops, emergent laparotomy for bowel resection
Teaching point: Pain out of proportion to exam + atrial fibrillation + elevated lactate = mesenteric ischemia until proven otherwise. CTA abdomen is the study of choice Bala et al. (ACS Surgery), 2022. Mortality exceeds 60% if diagnosis is delayed beyond 12 hours.
📋 Case 3, Acute Appendicitis
Patient: 28-year-old woman presents with 18 hours of periumbilical pain that has migrated to the RLQ. Anorexia, nausea, low-grade fever (38.2C). Positive McBurney point tenderness, positive Rovsing sign.
Key findings: WBC 14K with left shift. Beta-hCG negative. CT abdomen/pelvis shows dilated appendix (12 mm) with periappendiceal fat stranding and an appendicolith.
Management:
NPO, IV fluids, IV antibiotics (cefoxitin or ceftriaxone + metronidazole)
Surgery consult for appendectomy (laparoscopic preferred)
If perforated with abscess: percutaneous drainage + antibiotics, delayed interval appendectomy in 6-8 weeks
Teaching point: Classic appendicitis presents with visceral pain (periumbilical) migrating to somatic pain (RLQ) as inflammation involves the parietal peritoneum. Always check beta-hCG in women of childbearing age to rule out ectopic pregnancy. Laparoscopic appendectomy remains the gold standard WSES Guidelines, 2020.
📋 On Rounds
Pimp Questions
Why must every woman of childbearing age get a pregnancy test with abdominal pain?
Ectopic pregnancy can present as abdominal pain with or without vaginal bleeding and can rupture catastrophically → hemorrhagic shock → death in minutes. It is the #1 cause of first-trimester maternal death. A negative β-hCG essentially rules it out. Cost of the test is trivial compared to the consequence of missing it.
Does giving opioids for abdominal pain mask surgical findings?
No. This is a persistent myth. Multiple studies (including a Cochrane review) show that analgesics do not impair diagnostic accuracy and may actually improve exam quality by allowing patients to cooperate. Withholding pain control is unethical. Treat pain while completing the workup.
What is the significance of pain out of proportion to physical exam?
Classic for mesenteric ischemia. Early mesenteric ischemia causes severe visceral pain but the abdomen may appear benign on exam (no peritoneal signs yet -ischemia hasn't progressed to infarction/necrosis). By the time peritonitis develops, bowel is dead. High lactate + pain out of proportion + risk factors (Afib, atherosclerosis, hypercoagulable) → CTA abdomen STAT.
What are the Alvarado score components for appendicitis?
MANTRELS mnemonic: Migration of pain to RLQ (1), Anorexia (1), Nausea/vomiting (1), Tenderness in RLQ (2), Rebound (1), Elevated temp (1), Leukocytosis (2), Left shift (1). Total 10. Score 7+ = high probability, consider surgery. Score 5-6 = intermediate, get CT. Score 4 or less = low probability, observe.
When should you get a CT scan vs ultrasound for acute abdominal pain?
CT with IV contrast is the workhorse - sensitivity > 95% for most surgical emergencies. Preferred for: appendicitis in adults, diverticulitis, SBO, perforation, mesenteric ischemia. Ultrasound first-line for: RUQ pain/cholecystitis, pregnancy (avoid radiation), pediatric appendicitis, testicular torsion, AAA screening. Use MRI if US inconclusive in pregnancy.
What is the significance of "pain out of proportion to exam" beyond mesenteric ischemia?
Classic for mesenteric ischemia - severe pain but soft, nontender abdomen early on. Also seen in necrotizing fasciitis and compartment syndrome. In elderly with AFib or vascular disease + severe pain + benign exam, assume mesenteric ischemia until proven otherwise. CTA abdomen is diagnostic. Mortality > 60% if diagnosis delayed.
Clinical Examples
📋 Case 1, Perforated Peptic Ulcer
Patient: 55-year-old man with chronic NSAID use presents with sudden-onset severe epigastric pain radiating to the right shoulder (Kehr sign). Rigid abdomen, rebound tenderness, absent bowel sounds.
Key findings: Upright CXR shows free air under right hemidiaphragm. Lactate 3.2, WBC 18K. Tachycardic, BP 95/60.
Management:
NPO, IV fluids, broad-spectrum antibiotics (piperacillin-tazobactam)
Emergent surgery consult for exploratory laparotomy and repair
Pain control with IV fentanyl (does NOT mask surgical exam)
Teaching point: Free air under the diaphragm = perforated viscus until proven otherwise. This is a surgical emergency - surgical repair within 24 hours is associated with decreased mortality Soreide et al., 2015. Do not delay for CT if clinical picture is clear and patient is unstable.
📋 Case 2, Acute Mesenteric Ischemia
Patient: 72-year-old woman with atrial fibrillation (not on anticoagulation) presents with severe periumbilical pain for 6 hours. Pain is 10/10 but abdomen is soft and non-tender on palpation.
Key findings: Pain out of proportion to exam. Lactate 5.8. WBC 22K. CT angiography shows SMA thromboembolism with bowel wall thickening.
Management:
Emergent vascular surgery consult for embolectomy vs endovascular intervention
IV heparin anticoagulation
Aggressive IV fluid resuscitation, broad-spectrum antibiotics
If peritonitis develops, emergent laparotomy for bowel resection
Teaching point: Pain out of proportion to exam + atrial fibrillation + elevated lactate = mesenteric ischemia until proven otherwise. CTA abdomen is the study of choice Bala et al. (ACS Surgery), 2022. Mortality exceeds 60% if diagnosis is delayed beyond 12 hours.
📋 Case 3, Acute Appendicitis
Patient: 28-year-old woman presents with 18 hours of periumbilical pain that has migrated to the RLQ. Anorexia, nausea, low-grade fever (38.2C). Positive McBurney point tenderness, positive Rovsing sign.
Key findings: WBC 14K with left shift. Beta-hCG negative. CT abdomen/pelvis shows dilated appendix (12 mm) with periappendiceal fat stranding and an appendicolith.
Management:
NPO, IV fluids, IV antibiotics (cefoxitin or ceftriaxone + metronidazole)
Surgery consult for appendectomy (laparoscopic preferred)
If perforated with abscess: percutaneous drainage + antibiotics, delayed interval appendectomy in 6-8 weeks
Teaching point: Classic appendicitis presents with visceral pain (periumbilical) migrating to somatic pain (RLQ) as inflammation involves the parietal peritoneum. Always check beta-hCG in women of childbearing age to rule out ectopic pregnancy.
⚡ Summary
The Question Is Surgical or Not
Everything in the first hour is aimed at that one distinction.Surgical: perforated viscus with free air, mesenteric ischemia with necrotic bowel, ruptured abdominal aortic aneurysm, appendicitis, incarcerated hernia.Medical mimics that fill beds unnecessarily: DKA, inferior myocardial infarction, lower lobe pneumonia, adrenal crisis, hypercalcemia and porphyria.
Immediate Steps Before the Diagnosis
Two large-bore IVs, NPO, fluids, analgesia, labs including lipase and lactate, and an upright chest film or CT for free air.A beta-hCG in every woman of childbearing age, no exceptions, because a ruptured ectopic pregnancy presents as abdominal pain and kills quickly.
Give the Analgesia
The teaching that opioids mask peritoneal signs and delay diagnosis is disproven.Pain control improves the examination, because a patient who is not guarding from pain alone lets you find the guarding that matters. Withholding it delays nothing except the patient's comfort.
Pain Out of Proportion Is a Diagnosis
Severe pain with an unimpressive abdomen means mesenteric ischemia until proven otherwise. Look for atrial fibrillation, recent myocardial infarction or known vascular disease, and get CT angiography. A normal lactate early does not exclude it: lactate rises once the bowel is already infarcting, which is too late to be useful as a rule-out.
CT abdomen and pelvis with IV contrast is the most sensitive single test, above 95% for most surgical emergencies.Ultrasound first for suspected biliary disease, for pelvic pathology, and in pregnancy.An unstable patient does not go to the CT scanner: bedside ultrasound and the operating room, since a ruptured aneurysm or an unstable perforation is a clinical diagnosis.
Antibiotics-First Appendicitis Is a Real but Conditional Option
CODA showed antibiotics were non-inferior to appendectomy at 30 days for uncomplicated appendicitis, but 29% needed appendectomy within 90 days.An appendicolith predicts failure, and complicated disease with perforation or abscess still needs intervention. Frame it to the patient as a choice with a one-in-three chance of eventually needing the operation anyway.
Beware the Patient Who Does Not Look Sick
The elderly, the diabetic, the immunosuppressed and the patient on steroids can perforate without fever, leukocytosis or peritoneal signs.Age blunts every sign that the assessment depends on, so lower the imaging threshold rather than the level of concern. Serial examinations by the same clinician are more informative than a single exam by several.
Pemberton sign, facial plethora, JVD, and dyspnea when arms raised above head for 1 minute
Pemberton Sign: Ask the patient to raise both arms above the head for 60 seconds. Positive if facial congestion, cyanosis, or respiratory distress develop. Indicates thoracic inlet obstruction, highly suggestive of SVC syndrome or large mediastinal mass.
Severity Grading
Grade
Description
Symptoms
Urgency
Grade 0
Asymptomatic
Radiographic SVC obstruction only, no symptoms
Non-urgent
Grade 1
Mild
Facial/neck edema, mild dyspnea, no functional limitation
Non-urgent
Grade 2
Moderate
Significant edema, moderate dyspnea with exertion, head fullness
Semi-urgent
Grade 3
Severe
Severe edema, dyspnea at rest, mild cerebral symptoms (headache, dizziness)
True Emergency (Grade 4 only): Stridor or airway compromise, cerebral edema (altered mental status, obtundation, seizures), or hemodynamic instability. This is an oncologic emergency requiring immediate intervention (stenting, dexamethasone, possible emergent radiation). Most SVC syndrome is Grade 1-3, evolves over days to weeks with collateral formation and is NOT an immediate life threat. Do not panic, get tissue diagnosis first in stable patients.
🧪 Workup
Imaging
Study
Role
Details
CT chest with IV contrast
Test of Choice
Shows mass location/size, intraluminal thrombus, extent of SVC obstruction, collateral vessels, and guides biopsy planning. Sensitivity >95%.
CT venography (CTV)
Alternative
Better visualization of venous anatomy and thrombus extent. Use if contrast allergy with premedication.
MR venography (MRV)
Contrast allergy
No iodinated contrast needed. Good for thrombus and soft tissue detail. Slower, less available emergently.
Chest X-ray
Initial screen
Mediastinal widening (64%), pleural effusion (26%), right hilar mass. Normal CXR does NOT rule out SVC syndrome.
CBC with differential, leukocytosis (infection vs paraneoplastic), anemia
BMP, renal function (contrast planning), electrolytes
LDH, elevated in lymphoma, germ cell tumors
Uric acid, tumor lysis syndrome screen if bulky malignancy suspected
Coagulation studies, PT/INR, PTT (baseline before biopsy, anticoagulation planning)
AFP, beta-hCG, if mediastinal germ cell tumor suspected (young male with anterior mediastinal mass)
Flow cytometry, if lymphoma suspected (peripheral blood or tissue)
Tissue Diagnosis
Tissue diagnosis is CRITICAL before treatment in stable patients. Treatment depends entirely on histology. Empiric radiation can obscure the tissue diagnosis and render the tumor unbiopsyable. Only bypass biopsy if Grade 4 (airway compromise, cerebral edema).
CT-guided percutaneous biopsy, preferred if accessible mass, high diagnostic yield
Bronchoscopy with biopsy, if endobronchial lesion or central mass
Mediastinoscopy, direct visualization, higher yield but more invasive; GA risk in patients with severe SVC syndrome (airway collapse)
Thoracoscopy (VATS), for peripheral or pleural-based masses
Sputum cytology, low yield but non-invasive; reasonable first step
Lymph node biopsy, if palpable supraclavicular or cervical node (excisional preferred for lymphoma)
Elevate head of bed to 30-45 degrees, reduces venous pressure in head/neck
Dexamethasone 4 mg IV q6h, reduce airway and cerebral edema; especially effective if lymphoma suspected
Endovascular SVC stenting, fastest symptom relief (within hours). >90% technical success rate. Procedure of choice for emergent obstruction regardless of etiology
Emergent radiation, consider if stenting unavailable; 250-400 cGy x 2-4 fractions. Rapid shrinkage of radiosensitive tumors
Secure airway, prepare for difficult intubation (laryngeal edema); consider awake fiberoptic intubation. Avoid sedation that may worsen respiratory compromise
Supplemental O₂, maintain SpO₂ > 92%
Do NOT delay treatment for tissue diagnosis in Grade 4. Stent first, biopsy later. Airway protection takes absolute priority. Tissue can be obtained after stabilization.
Malignancy-Related SVC Syndrome
Tumor Type
Primary Treatment
Response
Notes
SCLC
Cisplatin/Etoposide chemotherapy
Highly chemo-sensitive (77% response)
Most responsive malignancy. Chemo is first-line, not radiation.
Lymphoma (NHL/HL)
R-CHOP or regimen-specific chemo
Highly chemo-sensitive (>80% response)
Steroids alone may produce dramatic shrinkage initially. Need tissue BEFORE steroids if possible (can obscure lymphoma dx).
NSCLC
Radiation ± chemotherapy
Moderate (60% response)
Less chemo-sensitive than SCLC. Radiation provides local control. Consider immunotherapy/targeted therapy based on molecular markers.
Germ cell tumor
BEP chemotherapy
Highly chemo-sensitive
Young males, anterior mediastinal mass. Check AFP/beta-hCG.
Thymoma
Surgery ± radiation
Variable
Surgical resection if feasible. Radiation for unresectable.
Endovascular stenting, symptomatic relief in 24-72 hours, >90% success rate. Used as bridge to definitive chemo/radiation, or for recurrent/refractory obstruction
Radiation therapy, for NSCLC and less chemo-sensitive tumors. Can be combined with chemo. Onset of relief in 1-2 weeks.
Thrombosis-Related SVC Syndrome
Anticoagulation, heparin infusion (aPTT-guided) → transition to warfarin or DOAC (rivaroxaban, apixaban). Duration: minimum 3 months; longer if ongoing risk factor (indwelling catheter)
Catheter removal, remove the offending catheter if no longer needed and safe to do so. If catheter is essential (e.g., chemo port), anticoagulate and consider exchange
Catheter-directed thrombolysis, alteplase infusion via catheter for acute/severe thrombosis with significant symptoms. Best results within 5-7 days of symptom onset
Endovascular stenting, for persistent stenosis after anticoagulation/thrombolysis, or if recurrent thrombosis
Supportive Care
Elevate HOB, 30-45 degrees at all times to reduce venous congestion
Supplemental O₂, titrate to SpO₂ > 92%
Diuretics, limited role (furosemide 20-40 mg IV). May provide temporary symptom relief by reducing intravascular volume but does not address obstruction. Avoid aggressive diuresis in dehydrated patients.
Avoid upper extremity IV access on affected side, elevated venous pressure causes unreliable drug delivery, inaccurate BP readings, and risk of compartment syndrome with tourniquets. Use lower extremity or femoral access.
DVT prophylaxis, consider in lower extremities (upper extremity already anticoagulated if thrombotic)
💊 Medications
Corticosteroids & Supportive
Drug
Dose
Purpose
Notes
Dexamethasone (Decadron)
4 mg IV q6h
Reduce airway/cerebral edema
First-line in emergent SVC syndrome. Especially effective if lymphoma suspected. Taper over 5-7 days once definitive treatment initiated.
Furosemide (Lasix)
20–40 mg IV
Temporary edema reduction
Limited evidence. May reduce intravascular volume and provide symptomatic relief. Avoid in dehydrated patients.
Anticoagulation (Thrombotic SVC Syndrome)
Drug
Dose
Monitoring
Notes
Heparin (UFH)
80 u/kg bolus → 18 u/kg/hr infusion
aPTT q6h (target 60-80s)
Preferred for acute/severe thrombosis. Short half-life, reversible with protamine. Bridge to oral anticoagulation.
Enoxaparin (Lovenox)
1 mg/kg SC q12h
Anti-Xa levels if renal impairment
Alternative to UFH for stable patients. Avoid if CrCl < 30 (use UFH instead).
Rivaroxaban (Xarelto)
15 mg BID x 21 days → 20 mg daily
CrCl, LFTs
Oral option for transition. No monitoring required. Avoid with strong CYP3A4 inhibitors.
Apixaban (Eliquis)
10 mg BID x 7 days → 5 mg BID
CrCl, LFTs
Preferred DOAC in renal impairment (less renal clearance). Safe down to CrCl 15.
Warfarin (Coumadin)
5 mg daily (adjust to INR 2-3)
INR q1-2 days until stable
Traditional option. Overlap with heparin x 5 days AND INR > 2 x 24h before stopping heparin.
Thrombolytics
Drug
Dose
Route
Notes
Alteplase (Activase)
0.5-1 mg/hr infusion x 12-24h
Catheter-directed
For acute thrombotic SVC syndrome (< 5-7 days). Lower dose than systemic lysis → fewer bleeding complications. Monitor fibrinogen q6h.
Chemotherapy by Cancer Type
Cancer
Regimen
Key Agents
Response to SVC Syndrome
SCLC
EP (Etoposide/Cisplatin)
Cisplatin 75 mg/m² D1 + Etoposide 100 mg/m² D1-3
77% response rate. Most chemo-responsive cause of SVC syndrome.
>80% response rate. Steroids alone may produce initial response.
Hodgkin
ABVD
Doxorubicin, Bleomycin, Vinblastine, Dacarbazine
Excellent response. Highly curable lymphoma.
Germ cell
BEP
Bleomycin, Etoposide, Cisplatin
Highly chemo-sensitive. Cure rates > 90% for good-risk disease.
📋 On Rounds
Pimp Questions
Why should you obtain tissue diagnosis before treating SVC syndrome?
Because treatment depends entirely on histology. SCLC gets chemo (cisplatin/etoposide), NSCLC may get radiation or targeted therapy, lymphoma gets R-CHOP. Empiric radiation can obscure tissue diagnosis and render the tumor unbiopsyable. Exception: Grade 4 (airway compromise, cerebral edema), stent first, biopsy later.
What is the fastest intervention for symptomatic SVC syndrome and what is its success rate?
Endovascular SVC stenting, symptom relief within hours, >90% technical success rate. Works regardless of etiology (malignant or thrombotic). Used as bridge to definitive chemo/radiation or as standalone for refractory obstruction. Preferred over emergent radiation because it provides immediate mechanical relief without obscuring tissue diagnosis.
Why should you avoid upper extremity IV access and BP measurements in SVC syndrome?
Avoid upper extremity IV access, blood draws, and BP measurements on the affected side. Venous pressures are markedly elevated → (1) IV fluids/drugs won't flow properly, (2) BP readings are inaccurate (falsely elevated venous component), (3) tourniquets can worsen edema and cause compartment syndrome. Use lower extremity or femoral access instead.
What is the Pemberton sign and what does it indicate?
Pemberton sign: ask the patient to raise both arms above the head for 60 seconds. Positive if facial congestion, cyanosis, JVD, or respiratory distress develop. Indicates thoracic inlet obstruction, the raised arms compress the thoracic outlet further, worsening SVC obstruction. Highly suggestive of SVC syndrome or large mediastinal mass. Simple bedside test.
Which malignancies causing SVC syndrome are most chemo-sensitive?
SCLC (77% response) and lymphoma (>80% response) are the most chemo-sensitive. For both, chemotherapy is first-line, NOT radiation. NSCLC is less responsive (~60%). Key point: steroids alone can dramatically shrink lymphoma, so avoid giving steroids before biopsy if lymphoma is suspected (can obscure the diagnosis and make tissue non-diagnostic).
How do you manage SVC syndrome caused by catheter-related thrombosis?
Anticoagulation (heparin → DOAC or warfarin) for minimum 3 months. Remove the catheter if no longer essential. If acute/severe (< 5-7 days), consider catheter-directed thrombolysis with alteplase. Endovascular stenting for persistent stenosis or recurrent thrombosis. If catheter is essential (e.g., chemo port), anticoagulate and consider exchange over a wire.
Clinical Examples
📋 Case 1, Lung Cancer with Progressive SVC Syndrome
Patient: 64 y/o M, 40-pack-year smoker, presents with 2 weeks of progressive facial swelling, neck fullness, and dyspnea on exertion. Notes his wedding ring and watch have become tight.
Key findings: Facial plethora, bilateral upper extremity edema, prominent chest wall veins. Pemberton sign positive. SpO₂ 94% on RA. CT chest: 6 cm right hilar mass encasing SVC with 80% luminal narrowing and extensive collateral vessels.
Management:
Elevate HOB to 45 degrees. Supplemental O₂ via NC.
Grade 2-3, stable, NOT an emergency. Pursue tissue diagnosis before treatment.
Endovascular SVC stenting for symptomatic relief (facial edema significantly impairing quality of life).
Definitive treatment: concurrent chemoradiation based on staging workup.
Teaching point: Most SVC syndrome from lung cancer evolves over weeks with collateral formation. Resist the urge to treat empirically, tissue diagnosis first. Stenting provides rapid symptomatic relief while awaiting definitive therapy.
📋 Case 2, Lymphoma with Acute Airway Compromise
Patient: 28 y/o M presents with 5 days of rapidly progressive facial swelling, orthopnea, and now stridor. Found to have anterior mediastinal mass on CXR.
Key findings: Severe facial edema, cyanotic, audible stridor, SpO₂ 88% on 15L NRB. CT chest: large anterior mediastinal mass compressing SVC and main bronchi. LDH 1,200, uric acid 9.2.
Management:
Grade 4, TRUE EMERGENCY. Do NOT delay treatment for tissue diagnosis.
Dexamethasone 10 mg IV stat, then 4 mg IV q6h (lymphoma likely, steroids may be cytolytic).
Emergent SVC stenting for airway and venous decompression.
Once stabilized: core needle biopsy → DLBCL confirmed. Start R-CHOP.
Teaching point: Grade 4 SVC syndrome with stridor is the one true emergency. Stent and steroids first. In young patient with anterior mediastinal mass + elevated LDH, lymphoma and germ cell tumor are top differentials. Always screen for TLS in bulky malignancy.
📋 Case 3, Catheter-Related SVC Thrombosis
Patient: 55 y/o F with metastatic breast cancer and right subclavian port placed 6 months ago. Presents with 3 days of right arm swelling, facial puffiness, and mild dyspnea.
Key findings: Right arm edema, mild facial edema, right-sided JVD. No stridor, no AMS. CT chest with contrast: thrombus extending from port tip into SVC with 60% occlusion. No progression of her known lung metastases.
Management:
Grade 1-2, thrombotic, not malignant compression. Not an emergency.
Start heparin infusion (aPTT-guided) → transition to apixaban 10 mg BID x 7 days → 5 mg BID.
Port still needed for ongoing chemo, do NOT remove. Anticoagulate through the port.
If symptoms worsen despite anticoagulation → catheter-directed thrombolysis or stenting.
Minimum 3 months anticoagulation; consider indefinite while port remains in place.
Teaching point: Catheter-related SVC thrombosis is managed medically with anticoagulation, not chemo/radiation. Remove the catheter only if it is no longer needed. Anticoagulation duration extends as long as the risk factor (device) persists.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 64-year-old with 40-pack-year smoking history who presented with 2 weeks of progressive facial and bilateral upper extremity edema, dyspnea, and prominent chest wall collaterals. CT chest shows a 6 cm right hilar mass with 80% SVC occlusion. Biopsy confirmed squamous cell NSCLC. He underwent SVC stenting yesterday with significant improvement and is being staged for concurrent chemoradiation."
Key Points to Cover on Rounds
Etiology: malignant vs thrombotic. Severity grade (1-4). Tissue diagnosis status, biopsy done? Histology result? Stent placed? Symptom trajectory, facial edema improving or worsening? Airway status, any stridor, voice changes, dyspnea trend? Access, all IVs and BP in lower extremities? Definitive treatment plan, chemo/radiation/anticoagulation timeline. TLS risk if bulky malignancy.
Facial and upper limb swelling, distended neck and chest veins, dyspnea and headache, worse on lying flat or bending forward.Most cases develop over weeks with collateral formation and allow time for tissue diagnosis.Airway compromise, stridor, cerebral edema or hemodynamic instability are what make it emergent.
Know the Two Cause Groups
Malignancy causes 60 to 85%, with lung cancer first and lymphoma second. Thrombosis causes 20 to 40%, driven by central venous catheters and pacemaker leads, and this proportion has risen with device use. The two are treated completely differently, so the cause has to be established before committing.
Get Tissue Before Treating, When You Can
Steroids or radiation can render a lymphoma unbiopsiable, and lymphoma is curable.In a stable patient, biopsy first.Only bypass this in grade 4 disease with airway or cerebral compromise, where stenting relieves the obstruction immediately without destroying the histology.
CT With Contrast Is the Diagnostic Test
It confirms the obstruction, shows the level and extent, distinguishes extrinsic compression from intraluminal thrombus, and identifies the mass to target for biopsy. Venography is rarely needed as a first study.
Stenting Gives the Fastest Relief
Endovascular stenting relieves symptoms within hours to days, faster than radiation or chemotherapy, and it does not depend on tumor sensitivity. It is first line for severe symptoms and for patients who need symptom control while a diagnosis is being made.
Match the Oncologic Treatment to the Tumor
Chemosensitive tumors, small cell lung cancer, lymphoma and germ cell tumors, respond to chemotherapy quickly and may not need a stent.Non-small cell lung cancer and other less chemosensitive tumors are treated with radiation or stenting. Steroids are commonly used but the evidence is weak outside lymphoma and radiation-induced edema.
Thrombotic SVC Syndrome Is an Anticoagulation Problem
Catheter-related thrombosis is treated with anticoagulation, and the catheter can often be retained if it is still needed and functioning.Consider catheter-directed thrombolysis for extensive, recent, symptomatic thrombus. This group does not need radiation or chemotherapy, which is why distinguishing it from malignant obstruction matters.
Supportive Measures Help and Cost Nothing
Elevate the head of the bed, give oxygen, and avoid IV access, blood pressure cuffs and venipuncture in the upper limbs, which drain into the obstructed system. Avoid diuretics as the primary treatment: the problem is mechanical obstruction, not volume overload, and dehydrating the patient worsens thrombosis risk without relieving the swelling.
Goals of care discussions define what treatments align with patient values. POLST/MOLST translates goals into actionable medical orders. DNR/DNI ≠ comfort care. Full code ≠ always appropriate. Document clearly.
🔍 Overview
Key Terminology
Term
Definition
Full Code
All resuscitative measures including CPR, intubation, vasopressors, defibrillation
DNR (Do Not Resuscitate)
No chest compressions or defibrillation if pulseless. Does NOT limit other treatments.
DNI (Do Not Intubate)
No endotracheal intubation. May still receive BiPAP, medications, other interventions.
DNR/DNI
No CPR AND no intubation. All other treatments still available unless specified.
Comfort Measures Only (CMO)
Focus entirely on symptom relief. No disease-directed treatments. Hospice-level care.
POLST/MOLST
Portable medical order translating goals into specific treatment decisions (antibiotics, fluids, hospitalization, CPR)
Advance Directive
Legal document expressing wishes for future care when unable to decide (living will, healthcare proxy)
Key Evidence: In-hospital CPR survival to discharge is ~15% overall, but < 5% in metastatic cancer and < 2% with sepsis-related arrest Ehlenbach, 2009. Early palliative care consultation improves quality of life and may extend survival Temel, 2010. Most patients prefer comfort-focused care when given accurate prognostic information Wright, 2008.
DNR ≠ "do not treat." A patient can be DNR and still receive ICU-level care, antibiotics, surgery, and full medical management. DNR ONLY addresses cardiac arrest.
🚨 Management
Framework for Goals of Care Conversation
Step
What to Say
1. Ask permission
"Would it be okay if we talked about what's most important to you regarding your medical care?"
2. Assess understanding
"What is your understanding of your illness and where things are?"
3. Explore values
"What's most important to you? What are you hoping for? What are you worried about?"
4. Share prognosis
"I wish things were different, but I'm worried that..." (wish-worry framework)
5. Make recommendation
"Based on what you've told me is important, I would recommend..."
6. Document
Document code status, healthcare proxy, POLST. Communicate to all team members.
CPR outcomes to share with patients: Overall in-hospital CPR survival to discharge ~15%. Witnessed shockable rhythm (VF/VT): ~30-40%. Metastatic cancer: < 5%. Age > 80 with comorbidities: ~5%. On vasopressors at time of arrest: < 2%. Sharing specific data helps patients make informed decisions Kaldjian, 2009.
Never ask: "Do you want us to do everything?" This question is uninformative - nobody would say no. Instead, explain what interventions entail and ask what outcomes are acceptable.
🧪 Workup
Information to Gather
Current understanding of illness/prognosis
Prior advance directives or POLST forms
Healthcare proxy/POA identification
Religious/spiritual considerations
Family dynamics and decision-makers
Prior experiences with hospitalization, ICU, mechanical ventilation
What quality of life means to the patient
💊 Medications
No specific medications for code status discussions. For symptom management in comfort care transitions:
Symptom
Medication
Dose
Pain
Morphine Sulfate
2–4 mg IV q2h PRN or 5–10 mg PO q4h
Dyspnea
Morphine Sulfate
2 mg IV q2h PRN (opioids treat air hunger)
Anxiety
Lorazepam (Ativan)
0.5–1 mg IV/SL q4h PRN
Secretions
Glycopyrrolate (Robinul)
0.2 mg IV q4h PRN or Scopolamine (Transderm Scōp) patch
Nausea
Ondansetron (Zofran)
4 mg IV q6h PRN
Agitation/delirium
Haloperidol (Haldol)
0.5–2 mg IV q4h PRN
Comfort care ≠ no care. Transitioning to comfort measures means aggressively treating symptoms while stopping disease-directed therapy. Opioids for dyspnea do NOT hasten death at appropriate doses Sykes, 2003. This is the principle of double effect: the intent is to relieve suffering, and the risk of hastening death is an accepted but unintended side effect.
📋 On Rounds
Pimp Questions
What is the difference between an advance directive and a POLST?
Advance directive is a LEGAL document completed by anyone (regardless of health status) expressing wishes for future care. It designates a healthcare proxy and/or describes treatment preferences. It is interpreted and must be translated into medical orders. POLST (Physician Orders for Life-Sustaining Treatment) is a MEDICAL ORDER signed by a physician for patients with serious illness.
Can you perform CPR on a patient who is DNR if they have a reversible cause of arrest?
No, unless the patient or surrogate specifically requests a "conditional" or "limited" code status. DNR means no CPR regardless of the cause. However, you CAN and SHOULD treat the reversible condition aggressively (e.g., give calcium for hyperkalemia, treat anaphylaxis) -treating the cause is NOT CPR. If a patient or family specifically requests "DNR except in case of X," this should be clearly documented.
How do you handle disagreement between family members about code status?
(1) Identify the legally designated healthcare proxy/POA - their decision has legal authority. (2) If no proxy, follow your state's surrogate hierarchy (spouse → adult children → parents → siblings). (3) Focus on "what would the patient want?" (substituted judgment). (4) Ethics committee consultation if unable to resolve. (5) Document all conversations and decisions.
What is the survival rate for in-hospital CPR?
Overall ~25% achieve ROSC, ~10-15% survive to discharge. In metastatic cancer, survival to discharge < 5%. In witnessed VF/VT arrest, ~30-40% survive. Ehlenbach, 2009 showed elderly patients (>80) have ~5% survival to discharge after in-hospital CPR. Giving patients specific numbers helps informed decision-making.
What is a time-limited trial and when should you use it?
A defined period (e.g., 48-72h) of aggressive treatment with specific, measurable goals. If goals not met, the family and team reassess. Useful when prognosis is uncertain or family needs time. Set clear endpoints: "If off vasopressors by Friday..." Quill, 2009 proposed this as a key palliative care tool.
What is the legal hierarchy of surrogate decision-makers?
Varies by state but typically: (1) Court-appointed guardian, (2) Healthcare proxy/POA, (3) Spouse, (4) Adult children, (5) Parents, (6) Siblings. Some states recognize domestic partners. The proxy's decision should reflect substituted judgment (what the patient would want), not the proxy's own preferences.
What is the difference between 'substituted judgment' and 'best interest' standard?
Substituted judgment: "What would the patient want based on their known values?" Used when patient's preferences are known or can be inferred. Best interest: "What would a reasonable person want?" Used when patient's wishes are completely unknown. Substituted judgment is preferred when possible.
Should DNR be suspended during surgery?
Yes, this is standard practice per ASA guidelines. A blanket DNR during surgery is inappropriate because most intraoperative arrests have reversible causes (anesthesia, bleeding, arrhythmia). A "required reconsideration" conversation should occur preoperatively to define which interventions are acceptable during/after surgery.
What are the components of a POLST form?
Section A: CPR (attempt/do not attempt). Section B: Medical interventions (full treatment, selective treatment, comfort-focused). Section C: Antibiotics (full, limited, comfort only). Section D: Artificially administered nutrition (long-term, defined trial, no artificial nutrition). Must be signed by physician + patient/surrogate.
Clinical Examples
📋 Case 1 - New Admission Code Status Discussion
Patient: 74F with metastatic NSCLC admitted for pneumonia. No advance directive on file. Alert, oriented, ECOG 3. Family present.
Key findings: Progressive cancer despite 2nd-line therapy. Declining functional status over 3 months. No prior documented goals of care conversation.
Management:
Initiate GOC conversation: "Given everything going on, I want to make sure we have a plan that matches your values"
Explore understanding: "What has your oncologist told you about where things stand?"
Clarify values: "If your heart were to stop, CPR has < 5% survival to discharge in metastatic cancer"
Recommend: "Based on what you've told me, I'd recommend focusing on treatments that keep you comfortable"
Document: DNR/DNI with clear rationale, update POLST, notify covering teams
Teaching point: Frame code status as a medical recommendation, not a menu choice. "Do you want us to do everything?" is a harmful question - patients cannot give informed consent without understanding outcomes.
📋 Case 2 - Surrogate Decision-Making for Incapacitated Patient
Patient: 68M with severe ARDS from aspiration pneumonia, intubated day 12, FiO₂ 80%, vasopressors × 2. PMH: advanced cirrhosis (MELD 34). No advance directive. Wife and adult son disagree.
Key findings: Predicted mortality > 90% (MELD 34 + ARDS + vasopressors). Wife wants to continue. Son says "Dad would never want this."
Management:
Identify legal surrogate (wife as spouse has legal priority in most states)
Family meeting with entire care team - present medical reality clearly
Use substituted judgment: "What would he say if he could see himself right now?"
Allow time - offer a time-limited trial: "Let's reassess in 48 hours"
If impasse persists → palliative care and ethics committee consultation
Teaching point: Time-limited trials are powerful tools. They give families permission to hope while creating a natural decision point. Set specific, measurable goals (e.g., "off vasopressors by Friday").
📋 Case 3 - Rapid Decompensation Requiring Emergent Decision
Patient: 82M with ESRD on HD, severe HFrEF (EF 15%), admitted with NSTEMI. Overnight: flash pulmonary edema → BiPAP → worsening. Full code. No family reachable.
Key findings: Impending respiratory arrest. Full code by default. Prior admission note documents patient saying "I don't want to be on machines" but no formal paperwork.
Management:
Honor full code status - intubate if needed (no legal basis to withhold without valid documentation)
Attempt emergent family contact via social work
Document the prior stated wishes in the chart but note they are not legally binding
Once stabilized: formal GOC conversation and advance directive completion
Consider palliative care consult for longitudinal goals discussion
Teaching point: Verbal statements without documentation are not actionable in emergencies. Always complete formal paperwork (POLST/MOLST, advance directive) when patients express end-of-life preferences.
⚡ Summary
Know Exactly What Each Order Limits
DNR: no chest compressions or defibrillation if pulseless. That is all it means.DNI: no endotracheal intubation, but BiPAP and everything else remain available.Comfort measures only: symptom relief with no disease-directed treatment.DNR is not DNI, and neither is comfort care, yet they are treated as a single package on wards every day.
DNR Does Not Mean Do Not Treat
A DNR patient can still receive ICU care, vasopressors, dialysis, antibiotics and surgery.The order addresses cardiac arrest and nothing else.Treatment quietly narrowing after a DNR is a documented and real phenomenon, and it is a failure of care, not an implication of the order.
Never Ask If They Want Everything Done
The question is uninformative, because nobody says no. It also implies the alternative is abandonment. Explain what each intervention actually involves and ask which outcomes would be acceptable, then recommend the plan that fits the answer.
Share Real CPR Numbers
In-hospital CPR survival to discharge is about 15% overall.A witnessed shockable rhythm is 30 to 40%; metastatic cancer, advanced age with comorbidity, or arrest while on vasopressors is around 5% or lower.Patients and families systematically overestimate success, largely from television, so the number itself changes decisions.
Distinguish the Documents
An advance directive is a legal document stating future wishes; a healthcare proxy names a decision-maker; POLST or MOLST is an actionable medical order set signed by a clinician and valid across settings, including for EMS.An advance directive in a drawer does not direct a paramedic; a POLST does. Verify what exists rather than assuming.
Ask What the Patient Would Say
Substituted judgment, not what the family wants. Reframing it as reporting the patient's values rather than choosing for them relieves the guilt that drives requests for non-beneficial treatment. When wishes were never expressed, fall back on best interests and be explicit that that is what you are doing.
Comfort Care Is Active Care
Transitioning to comfort measures means treating symptoms aggressively while stopping disease-directed therapy.Opioids at appropriate doses for dyspnea and pain do not hasten death, and withholding them out of that fear is the commonest way patients are left to suffer. Titrate to symptom relief.
Document and Revisit
Write the conversation, not just the order: who was present, what was discussed, what the patient valued, and the reasoning behind the plan. Code status is not permanent: revisit it as the clinical picture changes, since a decision made on admission may not fit a week later. Involve palliative care early, which improves quality of life and in some populations survival.
RoundsRx Infographic Series · #179 · Oncology & Palliative · PDF 138 KB
Text version
PALLIATIVE CARE · One Pager
Code Status & Advance Directives
Goals of care define which treatments match the patient's values; code status is the output, not the starting question. DNR ≠ comfort care, and full code ≠ always appropriate.
🧪 Terminology Residents Confuse
Full code: all resuscitative measures, CPR, intubation, vasopressors, defibrillation.
DNR: no compressions or defibrillation if pulseless. Nothing else is limited, so ICU care, antibiotics, and surgery all continue.
DNI: no endotracheal intubation, but BiPAP and medications remain available, so a DNI patient can still be escalated.
CMO: symptom relief only, no disease-directed treatment, hospice-level care.
Advance directive: legal document anyone can complete for future care. It must be interpreted and translated into orders, so it is not directly actionable at the bedside.
POLST/MOLST: physician-signed portable medical order for serious illness, actionable immediately, covering CPR, level of intervention, antibiotics, and artificial nutrition.
⚡ CPR Numbers To Quote (best to worst)
Witnessed shockable VF/VT: ~30–40% survive to discharge, the best-case scenario patients picture from television.
Overall in-hospital CPR: ~15% survive to discharge; ~25% achieve ROSC, so most who are resuscitated still never leave the hospital.
Age > 80 with comorbidities: ~5% survive to discharge.
Metastatic cancer: < 5% survive to discharge.
On vasopressors at arrest, or sepsis-related arrest: < 2%.
Give the actual numbers, not adjectives. Patients given quantitative outcome data choose DNR more often than those given qualitative descriptions, because you cannot consent to an outcome you cannot picture.
🚨 The Conversation, Step by Step
1
Ask permission: "Would it be okay if we talked about what's most important to you regarding your medical care?" Asking first lets the patient signal readiness, so the rest of the conversation is actually heard.
2
Assess understanding: "What is your understanding of your illness and where things are?" You cannot correct a mental model you have not heard.
3
Explore values: "What's most important to you? What are you hoping for? What are you worried about?" These answers are what your recommendation will be built on.
4
Share prognosis: wish-worry framing, "I wish things were different, but I'm worried that..." It delivers honesty without sounding like you are taking hope away.
5
Recommend: "Based on what you've told me is important, I would recommend..." Families in crisis cannot process an open menu; code status is a medical recommendation, not a choice you outsource.
6
Document: code status, healthcare proxy, POLST, then tell every covering team. A decision no one can find is a decision that will be reversed at 3 am.
💊 Comfort Care Symptom Orders
MorphinePain: 2–4 mg IV q2h PRN or 5–10 mg PO q4h. Dyspnea: 2 mg IV q2h PRN, opioids treat air hunger
Lorazepam (Ativan)0.5–1 mg IV/SL q4h PRN for anxiety
Glycopyrrolate (Robinul)0.2 mg IV q4h PRN for secretions, or scopolamine patch
Haloperidol (Haldol)0.5–2 mg IV q4h PRN for agitation and delirium
Ondansetron (Zofran)4 mg IV q6h PRN for nausea
Comfort care means treating symptoms aggressively while stopping disease-directed therapy. At appropriately titrated doses, opioids for dyspnea do not hasten death.
📊 Documentation
Code status in the EMR with the rationale, so the next team understands why, not just what.
Name the healthcare proxy or POA explicitly, because that person's decision carries legal authority when the patient cannot speak.
Update the POLST, because it is the order that travels with the patient outside the hospital.
Write a limited or conditional code verbatim ("DNR except in case of X"), because anything ambiguous defaults back to full code.
Notify all covering teams, and if a patient states a wish verbally, complete formal paperwork; verbal statements are not actionable in an emergency.
⚠️ Common Traps
Asking "Do you want us to do everything?" Nobody says no, so the answer carries no information and cannot support informed consent. Explain what each intervention involves and ask which outcomes are acceptable.
Treating DNR as "do not treat." DNR addresses cardiac arrest only.
Doing CPR on a DNR patient because the arrest cause looks reversible. Treat the cause aggressively (calcium for hyperkalemia, treat anaphylaxis), but that is not CPR, and DNR still applies unless a limited code was specifically requested.
Surgery: do the preoperative "required reconsideration" conversation to define which interventions are acceptable during and after the case, because most intraoperative arrests have reversible causes (anesthesia, bleeding, arrhythmia).
🏥 Who To Involve, And When
Family conflict: identify the legally designated proxy first; if none, follow your state's surrogate hierarchy (spouse → adult children → parents → siblings), because only one voice can be the decision-maker.
Reframe to substituted judgment: "What would the patient want?" is preferred whenever their values are known; fall back on the best-interest standard only when wishes are completely unknown.
Prognostic uncertainty or a family that needs time: offer a time-limited trial (e.g., 48–72h) with specific measurable endpoints, because it lets families keep hoping while creating a natural decision point.
Impasse after repeated meetings: palliative care, then ethics committee consultation.
Emergency with no valid documentation: honor full code, there is no legal basis to withhold, then hold the formal conversation once stabilized.
🎓 Key Evidence
Ehlenbach, 2009 in-hospital CPR survival falls with age and comorbidity; patients over 80 have ~5% survival to discharge.
Kaldjian, 2009 quantitative CPR outcome data shifts patients toward DNR more than qualitative description does.
Wright, 2008 end-of-life discussions lead to less aggressive care, earlier hospice, and better quality of life.
Temel, 2010 early palliative care in metastatic NSCLC improved quality of life and survival.
Sykes, 2003 appropriately titrated opioids for symptom control do not hasten death, the basis of the principle of double effect.
Quill, 2009 time-limited trials as the tool for prognostic uncertainty.
Related Topics
Family Meeting FrameworkGoals of Care & Symptom ManagementHospice Eligibility CriteriaNon-Opioid Symptom ManagementOpioid Rotation ConversionPalliative Extubation
EssentialPalliative
Family Meeting Framework
Structured approach to family meetings for goals of care, bad news delivery, and complex decision-making. Preparation, setting, and communication skills are essential. The SPIKES framework guides difficult conversations.
🔍 Overview
SPIKES Framework for Breaking Bad News
Step
Component
Example
S
Setting
Private room, sit down, phone off, tissues available. Ensure right people present.
P
Perception
"What is your understanding of what's been happening with your mom's health?"
I
Invitation
"Would it be okay if I shared some information about the test results?"
K
Knowledge
Use a warning shot: "I'm afraid I have some difficult news..." Then share information clearly.
E
Emotions
NURSE: Name, Understand, Respect, Support, Explore. "I can see this is really hard."
S
Summary/Strategy
Summarize, outline next steps, provide follow-up plan. "Let me make sure we're on the same page."
Evidence Base: The SPIKES framework was validated for breaking bad news in oncology Baile, 2000. VitalTalk training improves resident communication skills and family satisfaction Back, 2007. Early palliative care improves quality of life and may extend survival Temel, 2010.
🚨 Management
Before the Meeting
Pre-meeting huddle -align the medical team on prognosis and recommendations
Identify decision-maker -who has POA/proxy? Who else should attend?
Review chart -know the clinical facts, prognosis, treatment options
Set agenda -what decisions need to be made?
Book a private room -never deliver bad news in a hallway or shared space
During the Meeting
Introductions -everyone states their name and role
Ask before telling -"What is your understanding of what's been going on?"
Use clear, simple language -avoid jargon. Say "died" not "passed away"
Allow silence -silence after bad news is therapeutic, not awkward
Address emotions before information -respond to tears/anger before continuing
Make a recommendation -families want guidance, not just options
Summarize and document
Essential Phrases for Difficult Conversations
Situation
Phrase
Warning shot
"I'm afraid I have some difficult news..." / "I wish I had better news to share..."
Exploring understanding
"What is your understanding of what's been happening?"
Expressing empathy
"I can see how difficult this is." / "I wish things were different."
Making a recommendation
"Based on what you've told me about [patient's] values, I would recommend..."
Addressing "do everything"
"Help me understand what 'everything' means to you."
Prognostic honesty
"I hope for the best, but I'm worried that..."
Reframing for surrogates
"If [patient] could speak right now, what would they tell us?"
Time-limited trial
"Let's try this for [X days] and reassess. If we don't see [specific goal], that will help guide us."
🧪 Workup
Common Family Meeting Indications
New serious diagnosis (cancer, terminal illness)
Clinical deterioration despite treatment
Goals of care / code status discussion
Transition to comfort measures
Surrogate decision-making (incapacitated patient)
Family conflict about care plan
Prolonged ICU stay without improvement
💊 Medications
No medications specific to family meetings. Refer to code status/palliative sedation topics for comfort care medications when goals of care change.
📋 On Rounds
Pimp Questions
What is the most common mistake in family meetings?
Talking too much and not listening enough. The most effective family meetings involve asking open-ended questions and sitting with the answers. Families need to process emotions before they can process information. If you jump straight to medical facts without exploring understanding and emotions, families cannot absorb what you're saying.
How do you handle an angry family member in a meeting?
(1) Do not become defensive -anger is usually about fear, grief, or helplessness. (2) Name the emotion: "I can see you're frustrated, and that makes sense given how difficult this has been." (3) Validate: "Anyone in this situation would feel the same way." (4) Explore: "Can you tell me more about what's been hardest for you?" (5) Do NOT argue facts during emotional escalation -address emotions first, then return to medical information.
What is the NURSE mnemonic for responding to emotions?
Name: "It sounds like you're feeling scared." Understand: "I can understand why you'd feel that way." Respect: "You've been such a strong advocate." Support: "We're going to be with you through this." Explore: "Tell me more about what worries you most." Back, 2005.
What is the difference between 'code status' and 'goals of care'?
Code status = specific interventions (CPR, intubation). Goals of care = broader values and priorities (comfort, function, longevity). Goals of care should drive code status, not the other way around. Never ask "Do you want us to do everything?" - it implies not doing CPR means doing nothing.
What is a 'warning shot' and why is it important?
A brief statement preparing the listener for bad news: "I'm afraid I have some difficult news" or "I wish I had better news to share." Gives the brain a moment to shift from information-processing mode to emotional-processing mode. Without it, the actual bad news often isn't heard.
How should you handle family disagreement about care goals?
Identify the source: different understanding of prognosis, cultural/religious values, guilt, family dynamics. Separate meetings may help if one member dominates. Refocus on what the PATIENT would want: "If [patient] could speak for themselves, what would they say?" Ethics consult for persistent conflict.
What does 'I want everything done' usually mean?
Rarely means the family wants futile interventions. Usually means: "I love this person and don't want them to suffer or be abandoned." Explore the underlying fear: "Help me understand what 'everything' means to you." Often leads to comfort-focused goals once fears of abandonment are addressed.
When should you involve a palliative care consult vs conducting the meeting yourself?
Always appropriate for: prognostic uncertainty, family conflict, complex symptom management, cultural barriers, repeated meetings without resolution, trainee discomfort. But every physician should be able to conduct a basic goals-of-care discussion independently.
What is 'ask-tell-ask' communication?
Ask what the patient/family understands. Tell them the medical information in clear language. Ask what they understood and what questions they have. Ensures bidirectional communication. Avoids the common trap of monologue-style information dumping. Back, 2005 VitalTalk framework.
Clinical Examples
📋 Case 1 - Goals of Care in Advanced Cancer
Scenario: 72F with metastatic pancreatic cancer, now with new liver metastases after 2nd-line chemo. ECOG 3. Oncologist says no further treatment options. Family wants to discuss "what's next."
Approach:
Pre-meeting: Huddle with oncology - confirm no further disease-directed therapy. Align on prognosis (weeks to months).
Setting: Private conference room, oncologist + primary team + social work + chaplain if desired
Perception: "What is your understanding of where things stand with your mom's cancer?"
Warning shot: "I wish I had better news to share with you today..."
Knowledge: "The cancer has continued to grow despite treatment. We've reached a point where more chemo would cause harm without benefit."
Emotions: Pause. Allow silence. NURSE responses. "I can see how painful this is."
Recommendation: "Based on what you've told me about your mom valuing comfort and being at home, I'd recommend we focus entirely on her comfort and quality of life."
Teaching point: Always make a recommendation. Families in crisis cannot process open-ended options. "Given what you've told me about [patient's values], I would recommend..." is more helpful than listing choices.
📋 Case 2 - Surrogate Decision-Making in ICU
Scenario: 68M with severe stroke, intubated, GCS 5. No advance directive. Wife and adult children disagree - wife wants comfort care, son insists on "doing everything." Day 14 in ICU.
Approach:
Pre-meeting: Confirm with neurology: prognosis for meaningful recovery is very poor. Identify legal decision-maker (wife = default surrogate in most states).
Reframe: "We're not asking what YOU want - we're asking what [patient] would want if he could speak for himself."
Explore values: "What did [patient] say about situations like this? Did he ever talk about what quality of life meant to him?"
Address the son: "I can see how much you love your dad. Wanting everything done comes from that love. Help me understand what 'everything' means to you."
Time-limited trial: If no consensus, propose a defined period (e.g., 72h) with specific goals. "If we don't see improvement by Friday, that will help guide our next conversation."
Ethics consult: If conflict persists despite multiple meetings
Teaching point: Surrogate decision-making uses substituted judgment ("what would the patient want?") not best interest. Address the most resistant family member's underlying emotion - it's almost always fear or guilt, not medical disagreement.
📋 Case 3 - Delivering Unexpected Bad News
Scenario: 45M admitted for routine cholecystectomy. Intraoperative finding of disseminated peritoneal carcinomatosis. Pathology pending. Wife is in the waiting room expecting a routine post-op update.
Approach:
Setting: Move to a private room immediately. Do NOT deliver this news in the waiting area. Sit down, make eye contact.
Perception: "I know you were expecting a routine update about the gallbladder surgery..."
Warning shot: "During the surgery, we found something unexpected that I need to talk to you about."
Knowledge: "We found abnormal tissue throughout the abdomen that is very concerning for cancer. We've sent samples to pathology and should have more information in a few days."
Emotions: Stop talking. Let her react. "I'm so sorry. This is not the news anyone expected." Do NOT fill silence with medical details.
Next steps: "We don't have all the answers yet, but here is what we know and what happens next..." Arrange oncology consult. Offer social work/chaplain.
Teaching point: When delivering unexpected bad news, resist the urge to give all information at once. Give small pieces, pause, check understanding, respond to emotions, then continue. The family will not remember details from this conversation - they will remember how you made them feel.
⚡ Summary
Prepare Before You Walk In
Know the clinical facts, the prognosis and the realistic options, and agree them with the consultants first.A team that contradicts itself in front of a family destroys trust that cannot be rebuilt. Identify the decision-maker, arrange interpretation (a professional interpreter, not a relative), and decide in advance what recommendation you will make.
Use SPIKES
Setting: private room, everyone sitting, phones off, tissues out. Perception: 'What is your understanding of what has been happening?' Invitation: ask permission to share information. Knowledge: give a warning shot, then plain language in small pieces. Emotions: respond before continuing. Strategy and summary: agree the next steps.
Ask Before You Tell
Starting with the family's own understanding tells you where to begin and what misconceptions to correct. A family that already knows the situation needs confirmation and support; one that believes the patient is improving needs a very different conversation. Launching into a prepared speech wastes the most useful two minutes of the meeting.
Respond to Emotion Before Adding Information
NURSE: Name it, Understand, Respect, Support, Explore. Nothing said after a shock is retained, so continuing to talk through tears means the information has to be given again anyway. Silence is a technique, not an awkward gap: pause and let them speak first.
Make a Recommendation, Do Not Offer a Menu
Ask what matters to the patient, then recommend what fits.Do not ask 'do you want us to do everything?': it is unanswerable, it implies the alternative is doing nothing, and it puts the weight of a technical decision on a frightened family. Say 'based on what you have told me about your father, I would recommend...', which shares the burden rather than transferring it.
Use Language That Does Not Mislead
Avoid 'there is nothing more we can do': there is always more care, just not more disease-directed treatment. Avoid 'withdrawing care'; it is withdrawing a treatment while care continues and intensifies. Avoid euphemisms like 'passed on' and 'lost', which are frequently misunderstood. Say 'dying' and 'died' plainly.
Anchor Decisions in the Patient's Values
Ask what the patient would say if they were sitting here, not what the family wants.That reframing is what relieves the guilt that drives requests for non-beneficial treatment, because it makes the family the reporter of a decision rather than its author. Name the illness as the cause of death, not the decision.
Close With Concrete Next Steps
Summarize what was agreed, write it in the chart the same day, and say who will follow up and when.One meeting rarely settles everything, so schedule the next rather than leaving it open. Early palliative care involvement improves quality of life and, in some populations, survival, so it is an addition to care rather than a signal that treatment has stopped.
RoundsRx Infographic Series · #116 · Oncology & Palliative · PDF 139 KB
Text version
PALLIATIVE CARE · One Pager
Family Meeting Framework
Ask before you tell, respond to emotion before you give more information, and always end with a recommendation. Families cannot absorb medical facts until the feelings in the room have been addressed.
🧪 Before The Meeting
Pre-meeting huddle: align the medical team on prognosis and the recommendation, because a family that hears two different prognoses will anchor on the more optimistic one.
Identify the decision-maker: who holds POA or proxy, and who else needs to be in the room so the meeting does not have to be repeated.
Review the chart: know the clinical facts, prognosis, and remaining options before you walk in.
Set the agenda: name the specific decisions that need to be made, otherwise the meeting drifts and ends without one.
Book a private room: never deliver bad news in a hallway or shared space.
⚡ When To Call One
New serious diagnosis (cancer, terminal illness)
Clinical deterioration despite treatment
Goals of care or code status discussion
Transition to comfort measures
Surrogate decision-making for an incapacitated patient
Family conflict about the care plan
Prolonged ICU stay without improvement
🚨 SPIKES, Step by Step
S
Setting: private room, sit down, phone off, tissues out, right people present. Sitting signals you are not about to leave, which is what families read first.
P
Perception: "What is your understanding of what's been happening with your mom's health?" You have to hear their model before you can correct it.
I
Invitation: "Would it be okay if I shared some information about the test results?" Asking permission lets the family signal readiness, so the news is actually heard.
K
Knowledge: fire a warning shot first, "I'm afraid I have some difficult news...", then share clearly. Without the warning shot, the brain is still in information mode and the news does not register.
E
Emotions: NURSE, Name, Understand, Respect, Support, Explore. "I can see this is really hard." Address feeling before facts, because no one processes data while crying.
S
Summary and strategy: summarize, outline next steps, give a follow-up plan. "Let me make sure we're on the same page."
💬 Phrases That Work
Warning shot"I'm afraid I have some difficult news..." / "I wish I had better news to share..."
Exploring understanding"What is your understanding of what's been happening?"
Empathy"I can see how difficult this is." / "I wish things were different."
Recommendation"Based on what you've told me about [patient's] values, I would recommend..."
"Do everything""Help me understand what 'everything' means to you."
Prognostic honesty"I hope for the best, but I'm worried that..."
Reframing for surrogates"If [patient] could speak right now, what would they tell us?"
Time-limited trial"Let's try this for [X days] and reassess. If we don't see [specific goal], that will help guide us."
📊 In The Room
Introductions: everyone states name and role, so the family knows who is speaking for what.
Ask before telling, every time.
Plain language, no jargon. Say "died," not "passed away," because softened words get misheard as ambiguity.
Allow silence. Silence after bad news is therapeutic, not awkward; filling it with medical detail steals the family's processing time.
Emotions before information: respond to the tears or the anger before you continue, or nothing after that point is absorbed.
Make a recommendation. Families want guidance, not a menu of options they are not equipped to rank.
Ask-tell-ask: ask what they understand, tell in clear language, ask what they took away, which prevents monologue-style information dumping.
Summarize and document: attendees, discussion, decisions, follow-up plan, updated code status, then communicate to the team.
⚠️ Common Traps
Talking too much, listening too little: the single most common mistake. Jumping to medical facts before exploring understanding and emotion means the family cannot absorb any of it.
Arguing facts with an angry family member: anger is almost always fear, grief, or helplessness. Do not get defensive, name the emotion, validate it, explore it, and only then return to medical information.
Taking "I want everything done" literally: it rarely means a request for futile intervention. It usually means "I love this person and don't want them abandoned or suffering." Explore the fear and comfort-focused goals often follow.
Confusing code status with goals of care: code status is specific interventions, goals of care is values and priorities. Goals drive code status, never the reverse.
Delivering unexpected bad news all at once: give small pieces, pause, check understanding, respond, continue. The family will not remember the details, they will remember how you made them feel.
🏥 Get Help When
Palliative care consult for prognostic uncertainty, family conflict, complex symptom management, cultural barriers, repeated meetings without resolution, or trainee discomfort. Every physician should still be able to run a basic goals-of-care discussion independently.
Separate meetings when one family member dominates the room, so quieter voices can be heard.
Refocus on the patient when families disagree: "If [patient] could speak for themselves, what would they say?" The disagreement is usually about differing understanding of prognosis, culture or religion, guilt, or old family dynamics, not about medicine.
Ethics consult for conflict that persists across multiple meetings.
Chaplain and social work when spiritual or practical support is wanted; offer rather than wait to be asked.
🎓 Framework & Evidence
Baile, 2000 SPIKES, validated for breaking bad news in oncology.
Back, 2005 NURSE and ask-tell-ask, the VitalTalk frameworks for responding to emotion and structuring serious-illness conversations.
Back, 2007 VitalTalk training measurably improves resident communication skills and family satisfaction, so this is a teachable skill, not a personality trait.
Temel, 2010 early palliative care improves quality of life and may extend survival.
Related Topics
Code Status & Advance DirectivesGoals of Care & Symptom ManagementHospice Eligibility CriteriaNon-Opioid Symptom ManagementOpioid Rotation ConversionPalliative Extubation
High-YieldID
Tuberculosis
Mycobacterium tuberculosis -airborne transmission. Latent TB (positive PPD/IGRA, no symptoms) vs Active TB (cough, fever, night sweats, weight loss, cavitary lesions). Airborne isolation. 4-drug RIPE therapy × 6 months.
🔍 Overview
Latent vs Active TB
Feature
Latent TB (LTBI)
Active TB
Symptoms
None
Cough > 2–3 wks, hemoptysis, fever, night sweats, weight loss
CSF: lymphocytic, low glucose, high protein. NAAT on CSF.
Miliary TB
Disseminated, diffuse millet-seed nodules on CXR. Immunosuppressed patients.
Culture blood, urine, bone marrow.
TB Lymphadenitis (Scrofula)
Painless cervical LAD, most common extrapulmonary TB
FNA with AFB/culture.
Vertebral (Pott Disease)
Back pain, paraspinal abscess. Can cause cord compression.
MRI spine.
Pleural TB
Exudative effusion, lymphocytic, high ADA (>40)
Pleural biopsy most sensitive.
Pericardial TB
Effusion, may cause tamponade. Common in HIV+.
Pericardial fluid culture, biopsy.
Renal TB
Sterile pyuria, hematuria
Urine AFB cultures.
GI TB
Mimics Crohn disease. Ileocecal region most common.
Colonoscopy with biopsy, AFB culture.
TB Meningitis: Add Dexamethasone to RIPE for TB meningitis - reduces mortality by ~30% Thwaites, 2004. Extend total treatment to 9-12 months. Miliary TB also treated for 9-12 months.
"RIPE" Mnemonic for TB Treatment:R-Rifampin, I-Isoniazid, P-Pyrazinamide, E-Ethambutol. All 4 for initial 2 months, then RI for remaining 4 months = 6 months total.
Side Effects Mnemonic - Remember by the drug's first letter:
Rifampin = Red/orange body fluids
INH = Injury to liver (hepatotoxicity) + Injury to nerves (peripheral neuropathy)
Key Evidence: Standard 6-month RIPE remains the backbone of TB treatment BTS, 1998. For LTBI, the 3HP regimen (12-week INH + rifapentine) has equivalent efficacy with superior completion PREVENT TB, 2011. Rifampin x 4 months is now preferred over 9-month INH for LTBI in adults 4R vs 9H, 2018.
🧪 Workup
PPD (tuberculin skin test) -read at 48–72h. Induration (not redness) matters. Cutoff varies by risk.
IGRA (QuantiFERON, T-SPOT) -blood test, single visit, not affected by BCG vaccination
3 sputum AFB smears and cultures -collected 8–24h apart. Culture is gold standard (takes 2–6 wks).
NAAT (GeneXpert/Xpert MTB/RIF) -rapid PCR, also detects rifampin resistance
HIV test -all TB patients (TB-HIV coinfection common)
PPD Interpretation Cutoffs
Cutoff
Population
≥ 5 mm
HIV+, close contacts, immunosuppressed, CXR with old TB, organ transplant recipients
≥ 10 mm
Recent immigrants (< 5 yrs), IVDU, healthcare workers, residents of congregate settings, children < 4 yrs, high-risk medical conditions (diabetes, ESRD, silicosis)
≥ 15 mm
Low-risk individuals with no known TB exposure or risk factors
GeneXpert MTB/RIF Ultra: Rapid PCR with results in < 2 hours. Sensitivity ~96% for smear-positive, ~67% for smear-negative pulmonary TB Dorman, 2018. Simultaneously detects rifampin resistance. WHO recommends as initial diagnostic test for all suspected TB.
💊 Medications
Drug
Dose
Key Monitoring
Isoniazid (INH)
5 mg/kg (max 300 mg) daily
LFTs monthly. Give B6 (pyridoxine) to prevent neuropathy.
Rifampin (Rifadin)
10 mg/kg (max 600 mg) daily
LFTs. CYP450 inducer -check all drug interactions.
Pyrazinamide
25 mg/kg daily
LFTs, uric acid (causes hyperuricemia).
Ethambutol (Myambutol)
15–20 mg/kg daily
Visual acuity and color vision monthly.
Pyridoxine (Vitamin B6)
25–50 mg daily
Given with INH to prevent peripheral neuropathy.
📋 On Rounds
Pimp Questions
Why do you give pyridoxine (B6) with isoniazid?
INH inhibits pyridoxal phosphokinase → depletes active vitamin B6 (pyridoxine) → peripheral neuropathy (stocking-glove distribution). Risk factors: malnutrition, pregnancy, HIV, diabetes, alcoholism, renal failure. Give B6 25–50 mg daily to all patients on INH as prophylaxis.
What is the most feared side effect of ethambutol?
Optic neuritis -presents as decreased visual acuity, red-green color blindness, central scotomas. Usually dose-dependent and reversible if caught early. Check baseline visual acuity and color vision, then monthly. Discontinue immediately if visual changes occur.
When is a PPD considered positive at ≥5 mm?
HIV+, close contacts of active TB, immunosuppressed (TNF inhibitors, transplant), CXR with old healed TB. These are the highest-risk groups for reactivation. Lower-risk groups use ≥10 mm or ≥15 mm cutoffs.
Why is IGRA preferred over PPD in BCG-vaccinated patients?
BCG cross-reacts with PPD tuberculin, causing false positive PPD. IGRA uses M. tuberculosis-specific antigens (ESAT-6, CFP-10) not present in BCG or most NTM, so no cross-reactivity. Single blood draw, no return visit needed.
What is the 3HP regimen and why is it preferred for LTBI?
Isoniazid + Rifapentine weekly x 12 doses (DOT). PREVENT TB, 2011 showed equal efficacy to 9-month INH with better completion (82% vs 69%). Shorter = better adherence.
What drug interactions does rifampin cause?
Potent CYP3A4/2C9 inducer. Reduces levels of: warfarin, OCPs, HIV protease inhibitors, calcineurin inhibitors (cyclosporine, tacrolimus), methadone, azole antifungals. In HIV patients, substitute Rifabutin (Mycobutin) instead.
How do you monitor for hepatotoxicity during RIPE therapy?
Baseline LFTs, then monthly if risk factors (alcohol, liver disease, HIV, age >35). Hold all hepatotoxic drugs if AST/ALT >3x ULN with symptoms or >5x ULN without symptoms. Rechallenge sequentially: RIF first, then INH, then PZA.
What defines MDR-TB vs XDR-TB?
MDR-TB = resistant to rifampin + isoniazid. XDR-TB (2021 WHO definition) = MDR + resistant to fluoroquinolone + bedaquiline/linezolid. XDR mortality up to 50-80% in some settings.
When should you suspect TB meningitis?
Subacute headache + cranial nerve palsies (especially CN VI) + basilar meningitis. CSF: lymphocytic pleocytosis, low glucose, high protein, high ADA. Confirm with CSF NAAT. Start empiric RIPE + Dexamethasone per Thwaites, 2004.
Minimum 4 weeks of LTBI treatment should precede biologic initiation when possible
Key lesson: Biologic therapy (especially anti-TNF) is a major reactivation risk. Screen with IGRA before every biologic start. Treat and complete LTBI therapy first.
Case 3: Drug-Resistant TB (MDR-TB)
Patient: 28M with known TB, returns after incomplete treatment. GeneXpert and DST: MDR-TB - resistant to both Rifampin and Isoniazid.
Management:
Infectious disease + public health consultation essential - do not manage MDR-TB alone
Regimen per WHO 2022 guidance: Bedaquiline (Sirturo) + Linezolid (Zyvox) + Levofloxacin (Levaquin) as core agents
Minimum 18-month treatment course - substantially longer than drug-sensitive TB
Monitor for drug toxicities: bedaquiline (QTc prolongation), linezolid (bone marrow suppression, neuropathy), levofloxacin (tendinopathy, QTc)
Airborne isolation maintained; DOT mandatory throughout
Key lesson: MDR-TB = resistant to rifampin + INH. Treatment is prolonged, toxic, and complex - always requires specialist and public health co-management. Incomplete prior treatment is the #1 driver of drug resistance.
⚡ Summary
Isolate First, Ask Later
Airborne isolation, negative pressure room and N95 for staff, for ANY suspected active TB.Continue until 3 consecutive negative AFB smears collected 8 to 24 h apart, or the diagnosis is excluded. The isolation decision is made on suspicion, not on confirmation, because the exposure happens while the workup is pending.
Latent or Active
Latent: positive PPD or IGRA, no symptoms, normal chest x-ray, not infectious.Active: cough beyond 2 to 3 weeks, hemoptysis, fever, night sweats, weight loss, with cavitary or upper lobe disease and positive smears.Never treat latent TB without excluding active disease first: single-drug therapy in undiagnosed active TB generates resistance.
Diagnose Fast With GeneXpert
GeneXpert MTB/RIF Ultra gives a result in under 2 hours and simultaneously detects rifampin resistance, which is why WHO recommends it as the initial test. Sensitivity is about 96% in smear-positive but only about 67% in smear-negative pulmonary TB, so a negative result does not exclude disease. Still send 3 sputum samples for smear and culture, because culture remains the gold standard and is what gives full susceptibilities.
RIPE for 2 Months, Then RI for 4
Rifampin, Isoniazid, Pyrazinamide, Ethambutol for the first 2 months, then rifampin and isoniazid for 4 more, 6 months total. Ethambutol can be dropped once susceptibility confirms a fully sensitive organism.Use directly observed therapy, because incomplete treatment is what creates multidrug resistance.
Know the Toxicity by First Letter
Rifampin: Red or orange body fluids, and it is a potent CYP inducer that wrecks warfarin, oral contraceptives, azoles and antiretrovirals. Isoniazid: Injury to the liver, and Injury to nerves, so give pyridoxine 25 to 50 mg daily to prevent the peripheral neuropathy. Pyrazinamide: Painful joints from hyperuricemia, plus hepatotoxicity. Ethambutol: Eye, optic neuritis with loss of red-green discrimination, so check visual acuity and color vision at baseline and monthly.
Extend the Course for Certain Sites
TB meningitis and miliary TB are treated for 9 to 12 months.Bone and joint TB for 6 to 9 months.Add dexamethasone in TB meningitis, which reduces mortality by roughly 30% (Thwaites), and in pericarditis. Extend pulmonary treatment to 9 months if there is cavitation with a positive culture at 2 months, since that combination predicts relapse.
Latent TB Has Shorter Options Now
3HP, 12 weekly doses of isoniazid plus rifapentine, has equivalent efficacy with much better completion rates (PREVENT TB). Rifampin daily for 4 months is another short option with less hepatotoxicity than isoniazid. 9 months of isoniazid still works but completion is poor, and a regimen that is not finished is not a treatment.
Read the PPD Against the Right Cutoff
5 mm in HIV, recent contacts, fibrotic changes on chest x-ray, transplant recipients and anyone on prolonged steroids or a TNF inhibitor. 10 mm in recent immigrants from high-prevalence countries, injection drug users, healthcare and congregate-setting residents, and high-risk comorbidities. 15 mm in people with no risk factors. IGRA is preferred in BCG-vaccinated patients, because BCG causes a false positive PPD and does not affect the IGRA.
TMP-SMX (Bactrim) 15–20 mg/kg/day IV (TMP component) + prednisone if PaO₂ < 70
21 days. Add steroids if hypoxic.
Histoplasmosis (severe)
Amphotericin B (AmBisome) → Itraconazole (Sporanox)
Ampho × 1–2 wk → itra × 12 months
Candida in blood is NEVER a contaminant. Even a single positive blood culture for Candida = true candidemia. Treat every time. This is different from bacteria, where a single bottle of coag-negative staph may be a contaminant.
📋 Clinical Example -When to Treat Candida
Site
Significance
Action
Blood (even 1 bottle)
Always real -never contaminant
Echinocandin + remove ALL lines + ophtho consult + echo + blood cx q48h until clearance. 14 days after first negative cx.
Urine (candiduria)
Usually colonization, especially with Foley
Do NOT routinely treat. Treat only if: symptomatic UTI, neutropenic, pre-urologic procedure, or renal transplant. Remove/replace Foley first.
Sputum
Almost always colonization
Do NOT treat. Candida pneumonia is exceedingly rare. Sputum Candida does not warrant antifungals.
Wound / drain
Often colonization
Treat only if deep tissue/peritoneal culture + clinical signs of infection. Surface swabs are unreliable.
Key teaching point: Growing Candida from a non-sterile site (sputum, urine with Foley, superficial wound) is NOT the same as invasive candidiasis. Only blood cultures and deep sterile-site cultures warrant antifungal treatment.
🧪 Workup
Blood cultures -Candida grows in standard cultures. Aspergillus rarely grows from blood.
Galactomannan antigen -serum test for Aspergillus (sensitivity ~70% in neutropenic)
Beta-D-glucan (BDG) -pan-fungal marker. Elevated in Candida, Aspergillus, PJP. NOT in Crypto or Mucor.
Cryptococcal antigen (CrAg) -serum and CSF. Very sensitive and specific.
India ink stain -CSF for Crypto (encapsulated yeast). Less sensitive than CrAg.
Vori = first-line aspergillus. Fluconazole for step-down Candida. Check levels for vori.
Polyenes
Amphotericin B Liposomal (AmBisome)
Broadest spectrum. Nephrotoxic (liposomal form less so). Use for severe/refractory infections.
📋 On Rounds
Pimp Questions
Why must you remove central lines in candidemia?
Central venous catheters serve as a biofilm nidus for Candida -antifungals cannot penetrate biofilm effectively. Failure to remove lines is associated with persistent fungemia, metastatic complications (endophthalmitis, endocarditis), and increased mortality. Remove ALL central lines if possible and place new lines at a different site.
Why do you add steroids to PJP treatment?
In moderate-severe PJP (PaO₂ < 70 or A-a gradient > 35), the inflammatory response to dying organisms causes worsening respiratory failure. Prednisone 40 mg BID × 5 days, then 40 mg daily × 5 days, then 20 mg daily × 11 days reduces inflammation and improves survival. Must be started within 72h of treatment initiation.
📋 Case 1, ICU Candidemia
Patient: 58M in the MICU after abdominal surgery for perforated diverticulitis. Day 12 postop. On pip-tazo + vancomycin. Receiving TPN via PICC. New fever to 39.2°C, WBC 18K.
Start micafungin 100 mg IV daily, echinocandin is first-line for candidemia in critically ill patients (superior tolerability, unknown susceptibility)
Remove the PICC line immediately, Candida forms biofilm on catheters; antifungals cannot penetrate biofilm. New access at a different site.
Ophthalmology consult within 24 hours, endophthalmitis in 2-4% of candidemia; can cause blindness if missed
Echocardiogram, candidal endocarditis is rare but devastating; prosthetic valves at especially high risk
Blood cultures every 48 hours until two consecutive negatives. Duration: 14 days from first negative culture.
Step-down to fluconazole PO once stable, cultures clear, and susceptibilities confirm sensitivity
Teaching point: Candidemia risk = central line + TPN + broad-spectrum antibiotics + abdominal surgery + ICU days. All four present here = start antifungals without delay once blood cultures return positive.
📋 Case 2, Invasive Pulmonary Aspergillosis
Patient: 45M with AML, day 18 post-induction chemotherapy. ANC 80. New persistent fever despite broad-spectrum antibiotics × 5 days. Dry cough, mild hemoptysis.
Imaging: CT chest: 2.3 cm right lower lobe nodule with surrounding ground-glass halo ("halo sign").
Start voriconazole IV: 6 mg/kg q12h × 2 loading doses, then 4 mg/kg q12h. Switch to oral voriconazole once tolerating PO (excellent bioavailability).
Check voriconazole trough at day 5-7, target 1–5.5 mcg/mL. Below threshold = treatment failure. Above = hepatotoxicity, QTc, neurotoxicity.
Duration: 6–12 weeks minimum, continue until ANC recovery and CT improvement
Alternative if voriconazole fails: isavuconazole (fewer drug interactions, no QTc) or liposomal amphotericin B
Bronchoscopic biopsy not required when galactomannan + CT are diagnostic in high-risk neutropenic host
Teaching point: Aspergillus does NOT grow from routine blood cultures, serum galactomannan and CT findings are your diagnosis. The halo sign is most sensitive early; cavitation with air-crescent sign appears later as the infarct liquefies.
📋 Case 3, Cryptococcal Meningitis
Patient: 34F with HIV (not on ART), CD4 42. Three weeks of worsening headache, photophobia, mild confusion. Temperature 38.5°C. No focal deficits.
LP results: Opening pressure 42 cmH₂O. CSF: 35 WBC (lymphocytic), protein 89, glucose 32 (serum 110). India ink: budding yeast with thick capsule. Serum CrAg titer 1:1024. CSF CrAg positive.
Management steps:
Immediate therapeutic LP: Drain CSF to opening pressure <20 cmH₂O (remove 20–30 mL now). Elevated ICP is the leading cause of early death, this is urgent.
Induction: Liposomal amphotericin B 3–4 mg/kg IV daily + flucytosine 25 mg/kg PO q6h × 2 weeks
Consolidation: Fluconazole 400 mg daily × 8 weeks
Maintenance: Fluconazole 200 mg daily × 1 year (until CD4 >100 + suppressed viral load on ART)
Daily LPs until two consecutive normal pressures. If >4 LPs needed, place lumbar drain or VP shunt.
Delay ART 5–10 weeks, starting ART immediately risks IRIS (cryptococcal-IRIS can be fatal)
Teaching point: CrAg is far more sensitive than India ink or culture, use it for screening and diagnosis. Elevated ICP management (LP drainage) is as critical as antifungal therapy. Do NOT use acetazolamide or steroids for ICP in cryptococcal meningitis.
⚡ Summary
Candida in Blood Is Never a Contaminant
A single positive blood culture for Candida is true candidemia and is always treated. This is different from bacteria, where one bottle of coagulase-negative staphylococcus may well be skin flora. Treating it as a contaminant is a fatal error, since untreated candidemia seeds the eye, heart valves and spine.
Candidemia: Echinocandin, Remove the Line, Look in the Eye
Micafungin 100 mg IV daily or caspofungin, as first line even before speciation, because it covers the azole-resistant species. Remove every central line: the catheter is usually the source and the fungus lives in its biofilm. Treat for 14 days after the first negative blood culture, and get a dilated ophthalmologic exam, because endophthalmitis is often asymptomatic and changes the duration and the drug.
Aspergillus: Voriconazole and Watch the Levels
Invasive pulmonary aspergillosis in the neutropenic, transplanted or chronically steroid-treated patient.CT shows the halo sign early and the air-crescent sign later; serum and BAL galactomannan support the diagnosis. Voriconazole 6 mg/kg IV q12h for 2 doses, then 4 mg/kg q12h, for at least 6 to 12 weeks.Check troughs: metabolism varies enormously between patients, low levels fail and high levels cause visual disturbance, hepatotoxicity and encephalopathy.
Cryptococcal Meningitis Runs in Three Phases
Induction: liposomal amphotericin B plus flucytosine for 2 weeks. Consolidation: fluconazole for 8 weeks. Maintenance: fluconazole for at least a year.Diagnose with cryptococcal antigen, which is more sensitive than India ink.
The Detail That Saves Lives in Cryptococcus
Serial therapeutic lumbar punctures for raised opening pressure.Raised intracranial pressure, not the fungal burden, is what causes blindness and death, so an opening pressure above 25 cmH₂O gets drained daily until it settles. Delay antiretroviral therapy by 4 to 6 weeks in HIV, because starting it early precipitates immune reconstitution inflammatory syndrome in the CNS.
PJP: Treat and Add Steroids Early
TMP-SMX is both treatment and prophylaxis. Suspect it with bilateral ground-glass opacities, a raised LDH and exertional desaturation in HIV with CD4 below 200 or other immunosuppression. Add corticosteroids when the room-air PaO₂ is below 70 mmHg or the A-a gradient is above 35, which reduces mortality; give them before or with the first antibiotic dose, because killing the organism releases the inflammation that causes the deterioration.
Match the Endemic Mycosis to the Geography
Histoplasma: Ohio and Mississippi River valleys, bat and bird droppings; pneumonia with mediastinal adenopathy, diagnosed on urine and serum antigen, and it mimics sarcoidosis, which matters because steroids would be given to the wrong disease. Coccidioides: southwestern US deserts, with pneumonia, erythema nodosum and meningitis if disseminated. Ask where the patient has lived, not just where they live.
Know Why the Drug Class Was Chosen
Echinocandins are fungicidal against Candida, well tolerated and have few interactions, but they do not penetrate the CNS, eye or urine, so they are the wrong drug for candiduria, endophthalmitis and CNS disease. Azoles penetrate widely but are potent CYP inhibitors, so check every interaction, particularly with tacrolimus and warfarin. Amphotericin is broad and reliable but nephrotoxic and causes electrolyte wasting, so use the liposomal formulation and replace potassium and magnesium.
RPGN is a nephrology emergency. If creatinine is rising rapidly + active urine sediment (RBC casts, dysmorphic RBCs) - consult nephrology IMMEDIATELY for urgent biopsy. Untreated crescentic GN leads to irreversible ESRD within days to weeks. Do not wait for serologies to return before consulting.
Common Causes
Nephrotic
Nephritic
Minimal change disease (children #1)
IgA nephropathy (#1 worldwide)
FSGS (adults #1, especially AA)
Post-streptococcal GN (children)
Membranous nephropathy (PLA2R antibody)
Lupus nephritis (class III/IV)
Diabetic nephropathy
ANCA vasculitis (GPA, MPA)
Amyloidosis
Anti-GBM (Goodpasture)
Nephrotic Causes - Detailed
Cause
Association
Biopsy Finding
Minimal Change Disease
Children (#1), NSAIDs, lymphoma (Hodgkin)
Normal on light microscopy; podocyte foot process effacement on EM
FSGS
HIV, obesity, heroin, African Americans
Focal and segmental sclerosis of glomeruli
Membranous Nephropathy
PLA2R antibody, cancer (lung, colon), hepatitis B
Subepithelial deposits ("spike and dome" on silver stain)
Diabetic Nephropathy
#1 secondary cause in adults, long-standing DM
Kimmelstiel-Wilson nodules, mesangial expansion
Amyloidosis
AL (myeloma) or AA (chronic inflammation)
Congo red stain → apple-green birefringence
Nephritic Causes - Detailed
Cause
Key Features
Biopsy / Diagnosis
IgA Nephropathy
Most common GN worldwide (Berger disease). Episodic gross hematuria with URI.
Mesangial IgA deposits on IF
Post-Streptococcal GN
Children 1–3 wk after pharyngitis. ASO titer ↑, low C3.
Subepithelial "humps" on EM, granular IF ("lumpy-bumpy")
Lupus Nephritis
Class III (focal) and IV (diffuse) are most severe. Low C3/C4, dsDNA+.
"Full house" IF (IgG, IgA, IgM, C3, C1q)
ANCA Vasculitis
GPA (c-ANCA/PR3) or MPA (p-ANCA/MPO). Pauci-immune GN.
Crescentic GN with few/no immune deposits (pauci-immune)
Anti-GBM / Goodpasture
Pulmonary hemorrhage + GN. Anti-GBM antibodies.
Linear IgG staining along GBM on IF
MPGN
Low C3 and C4. Hepatitis C association.
Mesangial and subendothelial deposits, "tram-tracking" of GBM
🚨 Management
Nephrotic Syndrome Management
ACEi/ARB -reduce proteinuria (first-line for ALL proteinuric kidney disease)
Diuretics -loop diuretics for edema. May need albumin co-infusion if severe hypoalbuminemia.
Statin -hyperlipidemia management
Anticoagulation -consider if albumin < 2.5 (loss of antithrombin III → hypercoagulable state → renal vein thrombosis)
Key Evidence: Rituximab is now first-line for primary membranous nephropathy MENTOR, 2019. For ANCA vasculitis, rituximab is noninferior to cyclophosphamide for induction RAVE, 2010 and superior for maintenance MAINRITSAN, 2014. For lupus nephritis class III/IV, add mycophenolate or cyclophosphamide to steroids ALMS, 2009. Voclosporin added to standard therapy improves renal response in lupus nephritis AURORA, 2021.
Nephritic Syndrome Management
Treat underlying cause -immunosuppression for lupus nephritis, ANCA vasculitis
BP control -ACEi/ARB preferred
Supportive -fluid/salt restriction, diuretics if edema
Urgent nephrology + renal biopsy -rapidly progressive GN (RPGN) is an emergency
Anticoagulation in nephrotic syndrome: Membranous nephropathy has the highest thrombotic risk. Consider prophylactic anticoagulation when albumin < 2.5 g/dL. Renal vein thrombosis presents as flank pain, hematuria, and sudden worsening of proteinuria. Diagnose with CT venography or Doppler ultrasound Lionaki, 2012.
The kidney leaks antithrombin III (a key anticoagulant) in the urine along with other proteins. Loss of ATIII → uninhibited thrombin activity → hypercoagulable state. Clinical significance: renal vein thrombosis (especially in membranous nephropathy), DVT, PE. Consider prophylactic anticoagulation when albumin < 2.5 g/dL.
What is the most common cause of nephrotic syndrome in adults vs children?
Adults: FSGS (#1 overall, especially in African Americans) and membranous nephropathy (#1 primary cause in Caucasians). Diabetic nephropathy is the #1 secondary cause. Children: Minimal change disease (#1, ~80%). MCD responds dramatically to steroids -> 90% achieve remission within 4–8 weeks.
What is PLA2R antibody and why is it important?
Phospholipase A2 receptor antibody is positive in ~70% of primary membranous nephropathy. It distinguishes primary from secondary causes (cancer, lupus, hepatitis B). Titers correlate with disease activity and treatment response. MENTOR, 2019 showed rituximab is superior to cyclosporine for PLA2R+ MN.
What complement pattern helps distinguish nephritic causes?
Low C3 + C4: lupus nephritis, cryoglobulinemia (both activate classical pathway). Low C3 only (normal C4): post-streptococcal GN, C3 glomerulopathy, atypical HUS (alternative pathway). Normal complement: IgA nephropathy, ANCA vasculitis, anti-GBM disease (no complement consumption).
What is the significance of RBC casts on urinalysis?
RBC casts are pathognomonic for glomerulonephritis. They form when RBCs become trapped in Tamm-Horsfall protein casts within the tubules. Their presence confirms glomerular origin of hematuria (vs bladder, ureter, or kidney stone). Dysmorphic RBCs also suggest glomerular origin but are less specific.
When is renal biopsy indicated in nephrotic syndrome?
Adults: almost always indicated to guide treatment (except diabetic nephropathy with typical features - long-standing DM, retinopathy, no hematuria). Children: NOT needed for first episode with typical MCD presentation - empiric steroids. Biopsy if steroid-resistant, atypical features, or adult onset.
What is RPGN and why is it a nephrology emergency?
Rapidly Progressive Glomerulonephritis: loss of > 50% renal function over days to weeks. Characterized by crescents on biopsy (> 50% of glomeruli). Three categories: anti-GBM (type I), immune complex (type II: lupus, IgA, post-infectious), pauci-immune (type III: ANCA). Untreated leads to ESRD within weeks. Needs urgent biopsy and immunosuppression.
What is the MENTOR trial and what did it change?
MENTOR, 2019 (NEJM): Rituximab was noninferior to cyclosporine for inducing remission in membranous nephropathy at 12 months, and SUPERIOR at 24 months (60% vs 20% complete/partial remission). Rituximab is now first-line for primary MN. Less toxic than prior cyclophosphamide-based regimens.
Why do nephrotic patients develop hyperlipidemia?
Liver compensates for albumin loss by increasing protein synthesis, which includes increased lipoprotein (VLDL, LDL) production. Simultaneously, urinary loss of lipoprotein lipase cofactors reduces lipid clearance. Both mechanisms lead to marked hyperlipidemia. Treat with statins. Lipids normalize when nephrotic syndrome remits.
Clinical Examples
📋 Case 1 - Minimal Change Disease
Patient: 5-year-old boy presents with periorbital edema for 3 days. UA: 4+ protein, no blood. Labs: albumin 1.8 g/dL, cholesterol 380, Cr 0.4.
Diagnosis: Minimal change disease (most common nephrotic syndrome in children).
Key findings:
Nephrotic range proteinuria (4+) with severe hypoalbuminemia (1.8)
Periorbital edema - classic early sign in children (gravitational pooling while sleeping)
No hematuria - confirms nephrotic (not nephritic) pattern
Age 5 - MCD accounts for ~80% of nephrotic syndrome in children
Treatment: Prednisone 2 mg/kg/day (max 60 mg). Patient achieves complete remission within 4 weeks. No biopsy needed for first episode in children with typical presentation.
📋 Case 2 - ANCA Vasculitis (Nephritic)
Patient: 45M with gross hematuria, HTN (168/98), lower extremity edema. Labs: Cr 2.8 (baseline 1.0), UA with RBC casts. ANCA positive (p-ANCA/MPO).
Nephrotic range proteinuria (UPCR 8.2) with hypoalbuminemia and hyperlipidemia
PLA2R antibody positive - confirms primary membranous (~70% of cases)
Age-appropriate cancer screening needed - membranous can be paraneoplastic (lung, colon, breast)
High risk for renal vein thrombosis - membranous has the highest thrombotic risk of all nephrotic causes
Treatment: Started on rituximab (first-line immunosuppression for primary MN per MENTOR trial). ACEi for proteinuria reduction. Anticoagulation given albumin < 2.5. Monitor PLA2R titers for treatment response.
⚡ Summary
The Distinction Drives Everything
Nephrotic: proteinuria above 3.5 g/day, hypoalbuminemia, edema and hyperlipidemia, with a bland sediment.Nephritic: hematuria with dysmorphic red cells and red cell casts, hypertension, mild proteinuria and a falling GFR.Nephrotic is a podocyte problem; nephritic is inflammation of the glomerulus, and that difference decides both the differential and the urgency.
The Urine Sediment Is the Fastest Test You Have
Red cell casts = glomerulonephritis. Fatty casts and oval fat bodies with Maltese crosses under polarized light = nephrotic. Muddy brown casts = ATN. White cell casts = interstitial nephritis or pyelonephritis. Looking at the sediment yourself answers in minutes what serologies take days to confirm.
Nephrotic Causes by Population
Minimal change disease in children and with NSAIDs and lymphoma. FSGS, the commonest primary cause in adults, associated with HIV, obesity and heroin. Membranous nephropathy, associated with solid tumors, hepatitis B, lupus and anti-PLA2R antibodies. Diabetic nephropathy and amyloidosis as the systemic causes. Diabetes is the single commonest cause overall, so a long-standing diabetic with retinopathy and proteinuria often needs no biopsy.
Nephritic Causes by Complement and Serology
Low complement: post-infectious GN, lupus nephritis, membranoproliferative GN, cryoglobulinemia, endocarditis. Normal complement: IgA nephropathy, ANCA vasculitis, anti-GBM disease, Henoch-Schonlein purpura. Checking C3 and C4 early splits the differential in half before the biopsy result is back.
RPGN Is a Nephrology Emergency
A rapidly rising creatinine with an active sediment means call nephrology now for an urgent biopsy.Untreated crescentic glomerulonephritis causes irreversible end-stage renal disease within days to weeks, so the biopsy and empiric immunosuppression cannot wait for an outpatient appointment. Hemoptysis with nephritis means anti-GBM disease or ANCA vasculitis and needs plasma exchange considered alongside induction.
Baseline Nephrotic Management
Sodium restriction and loop diuretics for edema, often needing high or intravenous doses because diuretic bound to filtered albumin is less available. ACE inhibitor or ARB to reduce proteinuria, which is both a marker and a driver of progression. Statin for the hyperlipidemia.Treat the specific disease: steroids for minimal change, rituximab first line for primary membranous nephropathy (MENTOR).
Nephrotic Syndrome Is a Thrombotic State
Urinary loss of antithrombin III and other regulators makes these patients hypercoagulable.Membranous nephropathy carries the highest risk, and prophylactic anticoagulation is considered when albumin falls below 2.5 g/dL.Renal vein thrombosis presents as flank pain, hematuria and a sudden fall in renal function, and it is easy to attribute to the underlying disease instead.
Nephritic Management and the Immunosuppression Choice
Control blood pressure and volume, and treat the underlying cause.Post-infectious GN is supportive and usually self-limited.IgA nephropathy gets RAS blockade, with immunosuppression only for high-risk disease.ANCA vasculitis: rituximab is non-inferior to cyclophosphamide for induction (RAVE) and superior for maintenance (MAINRITSAN), and it avoids the infertility and bladder toxicity of cyclophosphamide. Also remember infection-related GN from endocarditis, where the treatment is antibiotics and source control, not immunosuppression.
Non-anion gap metabolic acidosis (NAGMA) caused by defective renal acid handling. Type 1 (distal): cannot secrete H⁺. Type 2 (proximal): cannot reabsorb HCO₃⁻. Type 4: hypoaldosteronism → hyperkalemia.
🔍 Overview
RTA Classification
Feature
Type 1 (Distal)
Type 2 (Proximal)
Type 4 (Hypoaldo)
Defect
Cannot secrete H⁺ in collecting duct
Cannot reabsorb HCO₃⁻ in proximal tubule
↓ Aldosterone effect → ↓ H⁺/K⁺ secretion
Serum K⁺
↓ Hypokalemia
↓ Hypokalemia
↑ Hyperkalemia
Urine pH
> 5.5 (cannot acidify)
< 5.5 (can acidify once bicarb threshold exceeded)
Type 4 RTA is the most common RTA. Most commonly caused by diabetic nephropathy (hyporeninemic hypoaldosteronism). ACEi/ARBs and K-sparing diuretics also cause it.
Remember RTA Types by K⁺: Type 1 and 2 have LOW K⁺ (1+2 = numbers go DOWN like K). Type 4 has HIGH K⁺ (4 = FOUR = FOURget aldosterone = hyperK).
Fanconi Syndrome
Generalized proximal tubular dysfunction. Think of it as "everything leaks through the proximal tubule."
Causes: Multiple myeloma (light chains), tenofovir, cisplatin, Wilson disease, lead poisoning
Key clue: Glucose in urine with NORMAL serum glucose = proximal tubular dysfunction, not diabetes
Approach to NAGMA: Algorithm
Step
Question
Answer
Interpretation
1
Is the anion gap normal?
AG <=12
Confirmed NAGMA. Proceed
2
Urine anion gap?
Negative (UCl > UNa + UK)
GI loss (diarrhea). Stop here
3
Urine anion gap?
Positive (UCl < UNa + UK)
RTA. Proceed to classify
4
Serum K+?
Hyperkalemia (>5.0)
Type 4 RTA. Check aldosterone/renin, medications
5
Serum K+?
Hypokalemia (<3.5)
Type 1 or Type 2. Check urine pH
6
Urine pH?
>5.5
Type 1 (Distal). Check for stones, autoimmune
7
Urine pH?
<5.5
Type 2 (Proximal). Check for Fanconi, myeloma
Clinical pearl: Type 4 RTA is by far the most common RTA encountered in clinical practice, but Type 1 and Type 2 are more commonly tested on boards. In the real world, most "Type 4 RTA" is simply a diabetic patient on an ACEi with K+ of 5.8 and bicarb of 20. DeFronzo, Kidney Int 1980
🚨 Management
Treatment by Type
Type 1 (Distal): Oral sodium bicarbonate or sodium citrate 1–2 mEq/kg/day. Potassium supplementation (KCl). Relatively easy to correct -low doses suffice.
Type 2 (Proximal): Oral sodium bicarbonate -but requires HIGH doses (10–15 mEq/kg/day) because bicarb is wasted in urine. Add thiazide diuretic (induces mild volume contraction → increases proximal reabsorption). K⁺ supplementation often needed.
Important: When giving bicarb to Type 1 or Type 2 RTA, monitor K+ closely. Bicarb administration causes K+ to shift intracellularly (H+/K+ exchange), which can worsen hypokalemia. Always replete K+ before or simultaneously with bicarb. Laing & Unwin, Nat Rev Nephrol 2015
🧪 Workup
ABG/VBG -non-anion gap metabolic acidosis (NAGMA)
BMP -serum HCO₃⁻, K⁺, anion gap
Urine pH -key differentiator (> 5.5 in Type 1)
Urine anion gap -(Na⁺ + K⁺) - Cl⁻. Positive = RTA (renal cause). Negative = GI HCO₃⁻ loss (diarrhea).
Serum aldosterone, renin (if Type 4 suspected)
Urine electrolytes
Diagnostic Approach
Step 1: Confirm NAGMA (normal anion gap metabolic acidosis)
Step 2: Calculate urine anion gap → Positive = RTA, Negative = GI loss (diarrhea)
Step 3: Check serum K⁺ → Hyperkalemia = Type 4, Hypokalemia = Type 1 or 2
Step 4: Check urine pH → >5.5 = Type 1 (cannot acidify), <5.5 = Type 2
Step 5: Look for associations → Stones/Sjögren = Type 1, Fanconi/myeloma = Type 2, DM/ACEi = Type 4
Type 2 -volume contraction increases proximal HCO₃⁻ reabsorption
📋 On Rounds
Pimp Questions
How does urine anion gap help differentiate causes of NAGMA?
Urine anion gap (UAG) = (UNa + UK) - UCl. In NAGMA from GI losses (diarrhea), the kidney compensates by excreting more NH₄⁺ (which carries Cl⁻) → UCl is high → UAG is negative (kidney is working). In RTA, the kidney CANNOT excrete acid properly → less NH₄⁺/Cl⁻ → UAG is positive (kidney is the problem). Mnemonic: "Negative is Normal" (the kidney is doing its job).
Why is Type 2 RTA harder to treat than Type 1?
In Type 2, the proximal tubule has a lowered threshold for HCO₃⁻ reabsorption. Any supplemental bicarb is filtered and immediately wasted in the urine (until serum bicarb falls below the lowered threshold). This means you need massive doses (10–15 mEq/kg/day), which also deliver a large sodium load → volume expansion → even more bicarb wasting. Adding a thiazide causes mild volume contraction, which increases proximal reabsorption efficiency.
What is the urine anion gap and how do you interpret it?
UAG = (UNa + UK) - UCl. It estimates urine NH4+ excretion. In normal renal response to acidosis, kidneys excrete lots of NH4+ (carried with Cl-), so UCl is high and UAG is negative. In RTA, kidneys cannot excrete acid properly, so NH4+/Cl- is low and UAG is positive. Mnemonic: "Negative is Normal" (kidneys doing their job, pointing to GI loss like diarrhea as the cause). Batlle et al, NEJM 1988
Why does Type 1 RTA cause kidney stones but Type 2 does not?
In Type 1 (distal) RTA, the persistently alkaline urine (pH >5.5) promotes precipitation of calcium phosphate stones (calcium phosphate is less soluble at high pH). Additionally, chronic acidosis causes bone buffering, releasing calcium into the blood and increasing urinary calcium excretion (hypercalciuria). The combination of alkaline urine + hypercalciuria = nephrocalcinosis and recurrent stones. Type 2 RTA has intermittently acidic urine (once serum bicarb falls below threshold), so stone risk is much lower. Caruana & Buckalew, Semin Nephrol 1988
How does the urine pH help differentiate Type 1 from Type 2 RTA?
Both Type 1 and Type 2 cause NAGMA with hypokalemia. The key differentiator is urine pH: Type 1: urine pH is ALWAYS >5.5 because the distal tubule fundamentally cannot secrete H+ (the defect). Type 2: urine pH is <5.5 once serum bicarb falls below the lowered reabsorption threshold (at that point, the filtered bicarb load is small enough for the proximal tubule to handle, and the intact distal tubule can acidify normally). So a patient with NAGMA + hypokalemia + urine pH <5.5 = Type 2. Urine pH >5.5 = Type 1.
What medications commonly cause Type 4 RTA?
Medications that impair the renin-angiotensin-aldosterone system or block aldosterone effect: (1) ACE inhibitors/ARBs - reduce angiotensin II and aldosterone production. (2) K-sparing diuretics - spironolactone, eplerenone (block aldosterone receptor), amiloride, triamterene (block ENaC). (3) TMP-SMX (Bactrim) - blocks ENaC like amiloride, causing hyperkalemia. (4) NSAIDs - reduce renin secretion via prostaglandin inhibition. (5) Heparin - directly inhibits aldosterone synthesis. (6) Calcineurin inhibitors (cyclosporine, tacrolimus). DeFronzo, Kidney Int 1980
A patient has NAGMA. How do you determine if it's RTA vs diarrhea?
Both RTA and diarrhea cause NAGMA. Use the urine anion gap (UAG): UAG = UNa + UK - UCl. Negative UAG = GI loss (diarrhea). The kidneys are working correctly, excreting NH4+ with Cl- to compensate. Positive UAG = RTA. The kidneys are the problem, unable to excrete acid. Then use K+ and urine pH to classify the RTA type. Also check clinical context: diarrhea is obvious clinically (stool history, volume status). RTA tends to be chronic and insidious. Rodriquez-Soriano, JASN 2002
Clinical Examples
📋 Case 1, Type 1 (Distal) RTA
Patient: 32F with Sjögren syndrome, fatigue, muscle weakness. BMP: K 2.8, HCO₃ 12, AG 10 (normal). Urine pH 6.2.
Glycosuria with normal serum glucose, pathognomonic for proximal tubular dysfunction
Rickets, from phosphate wasting (hypophosphatemia)
Failure to thrive, chronic acidosis impairs growth in children
Workup: Evaluate for underlying cause, in children, cystinosis is the most common cause. In adults, consider multiple myeloma (light chains), tenofovir, cisplatin.
⚡ Summary
Where RTA Sits
A non-anion-gap metabolic acidosis from defective renal acid handling, with the kidney rather than the gut losing the base. Calculate the urine anion gap to separate it from diarrhea: a negative gap means the kidney is excreting ammonium appropriately, so the loss is gastrointestinal; a positive gap means the kidney is not, which is RTA.
The Three Types in One Line Each
Type 1 (distal): cannot secrete hydrogen in the collecting duct.Type 2 (proximal): cannot reabsorb bicarbonate.Type 4: too little aldosterone effect, so both hydrogen and potassium secretion fall.
Potassium Sorts Them Fast
Types 1 and 2 are hypokalemic; type 4 is hyperkalemic.A non-gap acidosis with a high potassium is type 4 until proven otherwise, and that single observation does most of the work at the bedside.
Urine pH Separates 1 From 2
Type 1: urine pH stays above 5.5 even during acidemia, because the distal pump is broken and the urine cannot be acidified at all. Type 2: urine pH is below 5.5 once the serum bicarbonate falls below the reabsorptive threshold, since the distal mechanism works fine, and the bicarbonate simply stabilizes at a lower set point.
Type 4 Is the One You Will Actually See
It is by far the commonest RTA in practice, most often a diabetic with hyporeninemic hypoaldosteronism, usually on an ACE inhibitor or ARB. Also caused by potassium-sparing diuretics, NSAIDs, calcineurin inhibitors, TMP-SMX and heparin. Types 1 and 2 are tested more often than they are seen.
Match the Treatment to the Type
Type 1: modest bicarbonate or citrate (1 to 2 mEq/kg/day), which is usually enough because the deficit is fixed. Type 2: very large alkali doses (10 to 15 mEq/kg/day) plus a thiazide, because whatever is given is promptly wasted in the urine, and the thiazide induces mild volume contraction that enhances proximal reabsorption. Type 4: treat the hyperkalemia, stop the offending drug, and add fludrocortisone or a loop diuretic; alkali is rarely needed since correcting the potassium restores ammoniagenesis.
Replete Potassium Before the Bicarbonate
Giving bicarbonate shifts potassium into cells through hydrogen-potassium exchange, which deepens an existing hypokalemia and can cause arrhythmia or weakness.In types 1 and 2, replete or co-administer potassium, and use potassium citrate rather than sodium bicarbonate where hypokalemia is the problem.
Know the Complications and the Company They Keep
Type 1 causes nephrocalcinosis and calcium phosphate stones, because the persistently alkaline urine plus hypercalciuria and low urinary citrate is exactly the stone-forming recipe, and it also causes rickets or osteomalacia. Type 2 usually comes as part of Fanconi syndrome, with glycosuria at a normal serum glucose, phosphaturia, aminoaciduria and uricosuria, so look for multiple myeloma, tenofovir, ifosfamide and heavy metals. Type 1 is associated with Sjogren syndrome, lupus, amphotericin and lithium.
Prednisone (Deltasone)60 mg daily (or 1g IV methylpred × 3 days if vision threatened)
If GCA is suspected with visual symptoms → start high-dose steroids IMMEDIATELY. Do NOT wait for biopsy. Vision loss is irreversible. Biopsy can be done within 1–2 weeks of starting steroids without affecting results.
New temporal headache, jaw claudication, scalp tenderness, vision changes, fever
ESR/CRP
↑↑ (ESR often > 40–50)
↑↑↑ (ESR often > 50–100)
Treatment dose
Low-dose: Prednisone 15–20 mg daily
High-dose: Prednisone 60 mg daily (or IV methylpred 1g × 3d if vision loss)
Biopsy needed?
No -clinical diagnosis + response to steroids
Yes -temporal artery biopsy is gold standard (but do NOT delay treatment)
Duration of treatment
12–18 months taper (relapse common)
1–2 years taper; tocilizumab as steroid-sparing agent
GCA Red Flags -Act Immediately: • Jaw claudication (most specific symptom for GCA) • Sudden vision loss (anterior ischemic optic neuropathy -irreversible) • New headache in patient > 50 years old • Temporal artery tenderness or nodularity on palpation • Scalp tenderness (pain when combing hair)
Mnemonic -TEMPORAL for GCA Features: Temporal headache · ESR elevated (> 50) · Monocular vision loss · Polymyalgia overlap (15–20%) · Older age (> 50) · Response to steroids (dramatic) · Artery biopsy (skip lesions -may need bilateral) · Large vessel involvement (aortitis, subclavian)
🚨 Management
PMR Treatment
Prednisone (Deltasone) 12.5–25 mg daily -dramatic response within 24–72h (if no response, reconsider diagnosis)
Taper over 12–18 months (very slow -relapse is common)
Calcium + Vitamin D + DEXA (steroid-induced osteoporosis prevention)
↓ 2.5 mg every 2–4 weeks to 10 mg, then ↓ 1 mg/month. Total duration 12–18 months. Relapse common -increase dose if flare and re-taper slowly.
GCA (no vision loss)
Prednisone 60 mg daily
↓ 10 mg every 2 weeks to 20 mg, then ↓ 2.5 mg every 2–4 weeks to 10 mg, then ↓ 1 mg/month. Total 1–2 years.
GCA (with vision loss)
IV Methylprednisolone 1g daily × 3 days, then prednisone 60 mg
Same taper as GCA above after completing IV pulse. Add tocilizumab early for steroid-sparing.
🧪 Workup
ESR, CRP -both markedly elevated
CBC -normocytic anemia common, ↑ platelets
Temporal artery biopsy -GCA gold standard. Get ≥ 1 cm sample. Skip lesions mean negative biopsy doesn't exclude GCA.
Temporal artery US -"halo sign" (hypoechoic wall thickening). Increasingly used as first-line in Europe.
CK -normal in PMR (elevated CK → consider myositis instead)
RF, anti-CCP -negative (rule out RA, which can mimic PMR)
💊 Medications
Drug
Dose
Indication
Prednisone (Deltasone)
12.5–25 mg (PMR) / 60 mg (GCA)
First-line both conditions
Methylprednisolone (Solu-Medrol)
1g IV × 3 days
GCA with threatened vision loss
Tocilizumab (Actemra)
162 mg SC weekly
GCA steroid-sparing (GiACTA trial)
Methotrexate (Trexall)
7.5–15 mg weekly
Steroid-sparing in relapsing PMR (limited evidence)
Aspirin
81 mg daily
GCA -reduces ischemic events
📋 On Rounds
Pimp Questions
Should you wait for biopsy results before starting steroids in suspected GCA with vision symptoms?
Absolutely not. Vision loss from GCA (anterior ischemic optic neuropathy) is irreversible. Start high-dose steroids immediately -IV methylprednisolone 1g daily if vision is threatened. Temporal artery biopsy remains diagnostic for up to 2 weeks after starting steroids, so there is no reason to delay treatment. The risk of permanent blindness far outweighs the risk of a short course of steroids if the diagnosis turns out to be wrong.
📋 Case 1, Classic PMR Presentation
Patient: 72F presents with 3 weeks of bilateral shoulder and hip girdle pain, worse in the morning. Morning stiffness lasting 2 hours. Cannot lift arms above head or rise from a chair without assistance. No headache or vision changes.
Dramatic response within 24–48 hours -patient can raise arms and rise from chair by day 2
This dramatic response essentially confirms the diagnosis
Begin slow taper: ↓ 2.5 mg every 2–4 weeks to 10 mg, then ↓ 1 mg/month
Start calcium 1000 mg + vitamin D 800 IU daily, order DEXA scan (steroid osteoporosis prevention)
Monitor ESR/CRP q2–4 weeks during taper; counsel patient that relapse is common
Screen for GCA symptoms at every visit: headache, jaw claudication, vision changes
Key lesson: PMR responds dramatically to low-dose prednisone. If no improvement in 24–72h, reconsider the diagnosis. Normal CK rules out myositis; negative RF/anti-CCP rules out RA.
📋 Case 2, GCA with Jaw Claudication
Patient: 68M with 2 weeks of new-onset severe right temporal headache, jaw pain when chewing (jaw claudication), and scalp tenderness. No vision changes. Temporal artery is tender and nodular on palpation.
Plan: Taper prednisone (↓ 10 mg q2 weeks to 20 mg, then slow). Consider Tocilizumab (Actemra) for steroid-sparing.
Ophthalmology follow-up -monitor for visual complications
Key lesson: Jaw claudication is the most specific symptom for GCA. Start high-dose steroids immediately. Biopsy confirms but should never delay treatment.
📋 Case 3, PMR Patient with Sudden Vision Loss
Patient: 75F with known PMR on prednisone 10 mg (tapering), presents with sudden painless monocular vision loss in the left eye lasting 20 minutes, now resolved. Reports new left temporal headache × 3 days.
Exam: Left temporal artery tender, diminished pulse. Visual acuity 20/20 right, 20/200 left with afferent pupillary defect.
Labs: ESR 75 (rising from 30 on prior visit), CRP 38.
This is an ophthalmologic emergency:
IV Methylprednisolone 1g NOW -do not wait for any testing. Repeat daily × 3 days.
This is amaurosis fugax (transient ischemic visual loss) → impending permanent vision loss
Urgent ophthalmology consult within hours
After 3 days IV pulse → transition to prednisone 60 mg daily with slow taper
Add Tocilizumab (Actemra) 162 mg SC weekly as steroid-sparing agent
Temporal artery biopsy within 1–2 weeks
Key: 15–20% of PMR patients develop GCA -always screen for GCA symptoms during follow-up
Key lesson: PMR can evolve into GCA. Any new headache, jaw claudication, or vision changes in a PMR patient = emergent GCA workup. Vision loss from GCA is irreversible -IV methylprednisolone must be given immediately.
⚡ Summary
Two Related Diseases, Same Age Group
PMR: bilateral shoulder and hip girdle pain with morning stiffness beyond 45 min, in patients over 50.GCA: new temporal headache, jaw claudication, scalp tenderness and visual change.15 to 20% of PMR patients develop GCA, and about 40 to 50% of GCA patients have PMR symptoms, so each is a prompt to ask about the other.
Treat Suspected GCA Before the Biopsy
Start high-dose steroids immediately when GCA is suspected with visual symptoms. Do not wait.Vision loss from anterior ischemic optic neuropathy is irreversible and can become bilateral within days.The biopsy stays positive for 1 to 2 weeks after steroids start, so treating first costs nothing diagnostically.
Jaw Claudication Is the Most Specific Symptom
Pain in the masseters on chewing that eases with rest, from ischemia of the muscles of mastication. It carries the highest likelihood ratio of any GCA feature, well above headache or scalp tenderness, so asking about it directly is more useful than any single blood test.
Dose by Whether Vision Is Threatened
GCA without visual symptoms: prednisone 40 to 60 mg daily.GCA with visual loss or amaurosis: methylprednisolone 1 g IV daily for 3 days, then oral.PMR: prednisone 12.5 to 25 mg daily.Giving a PMR dose to GCA is a sight-threatening error, which is why the two diagnoses must be separated explicitly rather than treated as a spectrum.
The Steroid Response Is Diagnostic in PMR
Dramatic improvement within 24 to 72 h is expected.Failure to respond that quickly means reconsider the diagnosis: seronegative rheumatoid arthritis, inflammatory myopathy, hypothyroidism, malignancy or infection. Do not simply escalate the dose in a non-responder.
Interpret the Inflammatory Markers Carefully
ESR is often above 50 to 100 in GCA and above 40 in PMR, but normal markers occur in a small minority of GCA and do not exclude it when the clinical picture is strong. Check both ESR and CRP, since CRP is the more sensitive of the two and one may be raised without the other.
Biopsy a Long Segment, and Consider Ultrasound
Temporal artery biopsy remains the gold standard, but skip lesions mean a short segment gives false negatives, so take at least 1 to 2 cm and consider a bilateral biopsy. Temporal artery ultrasound showing the halo sign is a useful non-invasive alternative where expertise exists, and it is fastest when it is done before steroids blunt the findings.
Plan the Long Taper and Protect the Patient
PMR usually needs 1 to 2 years; GCA needs 1 to 2 years or longer, tapering slowly and guided by symptoms rather than by ESR alone.Tocilizumab is a proven steroid-sparing agent in GCA and reduces cumulative exposure and relapse; methotrexate is an option in relapsing PMR. Every patient needs bone protection with calcium, vitamin D and a bisphosphonate, plus glucose, blood pressure and cataract monitoring, because the steroid course is measured in years and its complications are what most of these patients ultimately suffer from. Screen GCA patients for thoracic aortic aneurysm, a late complication that appears years afterward.
Low PTH → hypocalcemia + hyperphosphatemia. Most common cause: post-thyroidectomy/parathyroidectomy. Chvostek and Trousseau signs. Treat with calcium + calcitriol. Monitor for QTc prolongation and seizures.
🔍 Overview
Pathophysiology
PTH maintains serum calcium by: (1) increasing renal Ca²⁺ reabsorption, (2) stimulating osteoclasts (bone resorption), (3) activating vitamin D (1,25-dihydroxy) in the kidney → ↑ intestinal Ca²⁺ absorption. Loss of PTH → low calcium, high phosphate.
Etiology
Cause
Details
Post-surgical (#1)
After thyroidectomy or parathyroidectomy -parathyroid glands damaged/removed
Always check magnesium in hypocalcemia. Hypomagnesemia causes functional hypoparathyroidism -PTH cannot be secreted or act properly. Calcium will NOT correct until magnesium is repleted.
Causes of Hypoparathyroidism
Cause
Mechanism
Key Feature
Post-surgical (most common)
Parathyroid glands damaged or removed during thyroidectomy/parathyroidectomy
Hypocalcemia within 24–72h post-op; may be transient or permanent
Autoimmune
Autoimmune destruction of parathyroid glands (APS-1: AIRE gene mutation)
Associated with mucocutaneous candidiasis, adrenal insufficiency
Magnesium -check in ALL hypocalcemia. Low Mg → functional hypoPTH
25-OH vitamin D -rule out deficiency (common confounder)
ECG -prolonged QTc
💊 Medications
Drug
Dose
Purpose
Calcium Gluconate
1–2g IV over 10–20 min
Acute symptomatic hypocalcemia -peripheral IV safe
Calcium Chloride
1g IV
3× more elemental Ca than gluconate -central line only (tissue necrosis risk)
Calcitriol (Rocaltrol)
0.25–2 mcg daily
Active vitamin D -replaces PTH-dependent activation
Calcium Carbonate (Tums)
500–1500 mg elemental Ca TID
Chronic oral replacement. Take with food (needs acid for absorption).
Magnesium Sulfate
2–4g IV
Correct hypomagnesemia FIRST -calcium won't correct otherwise
📋 On Rounds
Pimp Questions
Why must you check magnesium before treating hypocalcemia?
Magnesium is essential for both PTH secretion and PTH action at target organs. When Mg is < 1.0 mg/dL: (1) PTH secretion is impaired (despite low calcium, PTH remains low), (2) PTH receptors are resistant. Giving calcium without fixing magnesium is futile -the body cannot maintain calcium homeostasis. Always check and correct Mg first in any hypocalcemia.
📋 Case 1, Post-Thyroidectomy Hypocalcemia
Patient: 54F, post-op day 1 from total thyroidectomy for papillary thyroid carcinoma. Reports perioral tingling and fingertip numbness.
Exam: Chvostek sign positive (facial twitch on tapping). Trousseau sign positive. HR 88, BP 118/72.
Labs: Total Ca 6.8 mg/dL (low), ionized Ca 0.82 mmol/L (low), PO₄ 5.2 (high), PTH < 5 pg/mL (low), Mg 2.0 (normal).
ECG: Prolonged QTc at 510 ms.
Management:
Calcium gluconate 2g IV over 10 min → symptoms improve within minutes
Start continuous calcium drip at 1 mg/kg/hr elemental calcium
Continuous telemetry for QTc monitoring
Begin Calcitriol (Rocaltrol) 0.5 mcg BID + oral calcium carbonate 1g TID
Check ionized Ca q4–6h; taper IV calcium as oral takes effect
Counsel patient: may need lifelong calcium + calcitriol if parathyroids do not recover
Key lesson: Post-thyroidectomy hypocalcemia is the #1 cause of hypoparathyroidism. Always monitor calcium in the first 24–72h post-op. Symptomatic patients need IV calcium urgently.
📋 Case 2, DiGeorge Syndrome with Seizure
Patient: 8-month-old male with known 22q11.2 deletion (DiGeorge syndrome), history of tetralogy of Fallot repair. Presents with generalized tonic-clonic seizure lasting 2 minutes.
Labs: Ionized Ca 0.7 mmol/L (critically low), total Ca 5.9 mg/dL, PO₄ 7.1 (high), PTH < 3 pg/mL, Mg 1.8 (normal).
Management:
IV calcium gluconate 100 mg/kg (max 2g) slow push over 10 min with cardiac monitoring
Seizure resolves with calcium correction
Start Calcitriol (Rocaltrol) 0.25 mcg daily + oral calcium supplements
Low-sodium diet (Na increases urinary Ca excretion)
Nephrology consult for CKD management
Monitor 24h urine calcium q3–6 months, renal US annually
Key lesson: Chronic hypoparathyroidism management is a balancing act. Aim for low-normal serum Ca to minimize urinary calcium losses. Thiazides and PTH replacement (Natpara) are key tools for preventing nephrocalcinosis.
⚡ Summary
The Biochemical Signature
Low PTH with low calcium and high phosphate.That combination is what distinguishes it from vitamin D deficiency and chronic kidney disease, where PTH is high. PTH normally raises calcium and wastes phosphate, so its absence moves both in the opposite direction.
Post-Surgical Is the Commonest Cause
After thyroidectomy or parathyroidectomy, from gland removal, devascularization or injury. Other causes: autoimmune (APS-1), infiltrative (hemochromatosis, Wilson disease, metastases), DiGeorge syndrome (22q11 deletion), radiation, and hypomagnesemia.Check calcium in every post-thyroidectomy patient, since the fall typically appears within 24 to 72 h.
Check Magnesium Every Time
Magnesium below about 1.0 causes functional hypoparathyroidism: PTH can neither be secreted nor act properly. The calcium will not correct until the magnesium is repleted, no matter how much calcium is given. This is the commonest reason apparently refractory hypocalcemia stays refractory.
Recognize the Emergency
CHVOSTEK: Chvostek sign, Hyperreflexia, Vitals with a prolonged QT, Obtundation and seizures, Spasm (Trousseau), Tetany, Excitability. Laryngospasm, seizures and arrhythmia are what make it urgent, and they can appear before the numbers look alarming.
Acute Treatment
Calcium gluconate 1 to 2 g IV over 10 to 20 min for symptomatic hypocalcemia, followed by an infusion (5 to 10 g in 500 mL D5W over 12 to 24 h), because a bolus alone wears off within hours. Give magnesium at the same time if it is low. Continuous ECG monitoring, since the QT prolongation is what precedes the arrhythmia.
Chronic Treatment Is Calcium Plus an Active Vitamin D
Oral calcium 1 to 2 g of elemental calcium daily in divided doses, plus calcitriol 0.25 to 2 mcg daily.Calcitriol, not plain vitamin D: PTH is what drives renal 1-alpha-hydroxylation, so without it ergocalciferol and cholecalciferol are never activated. Add a thiazide to reduce urinary calcium losses if hypercalciuria develops.
Aim Low, Not Normal
Target a calcium at the low end of normal, around 8.0 to 8.5 mg/dL, and just enough to keep the patient symptom-free.Without PTH the kidney cannot reabsorb calcium, so normalizing the serum level dumps calcium into the urine and causes nephrocalcinosis, stones and chronic kidney disease. Monitor 24-hour urine calcium, not just the serum value.
Distinguish It From Pseudohypoparathyroidism
Same calcium and phosphate picture, but PTH is high, because the target tissue is resistant rather than the gland being absent. Albright hereditary osteodystrophy, with short stature, round face and shortened fourth metacarpals, is the classic phenotype. The treatment is similar, but the genetics, counseling and associated endocrinopathies are not, so the PTH level is worth checking before assuming a surgical cause in a patient with no surgical history.
RoundsRx Infographic Series · #163 · Renal & Metabolic · PDF 145 KB
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ENDOCRINE · One Pager
Hypoparathyroidism
Low PTH gives low calcium and high phosphate; replace with calcium plus ACTIVE vitamin D, because without PTH the kidney cannot activate vitamin D on its own.
🧪 Lab Pattern & Workup
The triad: ↓ Ca, ↓ PTH, ↑ PO₄. PTH normally drives renal phosphate excretion, so losing PTH raises phosphate at the same time it drops calcium. A low calcium with a high PTH is a different disease entirely.
Serum calcium, corrected for albumin: add 0.8 per 1 g of albumin below 4, because roughly half of measured calcium is albumin-bound and hypoalbuminemia fakes hypocalcemia.
Ionized calcium is the most accurate measure and is what you titrate acute therapy against.
PTH low or inappropriately normal confirms hypoparathyroidism: any normal value in the face of hypocalcemia is inappropriate, since a healthy gland should be maximally stimulated.
Magnesium in ALL hypocalcemia. Mg < 1.0 impairs both PTH secretion and end-organ PTH action, producing functional hypoparathyroidism that will not respond to calcium alone.
25-OH vitamin D to exclude simple deficiency, which is a common confounder of a low calcium.
ECG for prolonged QTc, the finding that converts a lab abnormality into a torsades risk.
⚡ Causes, Most Common First
Post-surgical (#1), after thyroidectomy or parathyroidectomy: glands damaged or removed. Hypocalcemia appears within 24-72 h post-op, which is exactly why calcium is monitored through that window. May be transient or permanent.
Hypomagnesemia (functional), Mg < 1.0: PTH is low despite low calcium because secretion is impaired and receptors are resistant. Reversible once Mg is repleted, so it is the one cause you can cure at the bedside.
Autoimmune, autoimmune polyendocrine syndrome type 1 (APS-1, AIRE gene mutation): look for mucocutaneous candidiasis and adrenal insufficiency alongside it.
Infiltrative (hemochromatosis, Wilson disease, metastatic cancer): iron or copper deposition destroys gland tissue. Check ferritin and ceruloplasmin, and look for liver disease and skin changes.
DiGeorge syndrome, 22q11.2 deletion: absent or hypoplastic parathyroids plus thymic aplasia, with cardiac defects and characteristic facies. Congenital, so there is no chance of recovery.
🚨 Acute Symptomatic Hypocalcemia, Step by Step
1
Check and correct magnesium first: MgSO₄ 2-4 g IV if low. Calcium will not correct while Mg is depleted, because PTH can neither be secreted nor act.
2
Calcium gluconate 1-2 g IV over 10-20 min. Preferred over CaCl₂ for a peripheral IV because it causes far less tissue necrosis on extravasation. Symptoms improve within minutes.
3
Continuous infusion 0.5-1.5 mg/kg/hr of elemental calcium, since a single bolus wears off quickly. Titrate against ionized calcium checked q4-6h.
4
Continuous telemetry. Prolonged QTc carries a torsades risk, and correcting magnesium at the same time addresses the other half of that risk.
5
Start oral therapy early: calcitriol plus calcium carbonate, then taper the IV as the oral regimen takes effect, so the patient is not tethered to a drip.
6
Set expectations: after thyroidectomy, counsel that calcium plus calcitriol may be lifelong if the parathyroids do not recover; in DiGeorge, replacement is definitely lifelong.
💊 Key Drugs
Calcium gluconate1-2 g IV over 10-20 min for acute symptomatic hypocalcemia. Safe peripherally, which is why it is the default in an unstable patient without central access.
Calcium chloride1 g IV. Delivers 3× more elemental calcium than gluconate, but central line only because of tissue necrosis risk.
Magnesium sulfate2-4 g IV. Correct hypomagnesemia FIRST; otherwise calcium repletion fails no matter how much you give.
Calcitriol (Rocaltrol)0.25-2 mcg daily. This is active vitamin D and it bypasses the PTH-dependent 1-alpha hydroxylation step that these patients cannot perform.
Calcium carbonate (Tums)500-1500 mg elemental Ca TID (1-3 g/day in divided doses). Take with food, since carbonate needs gastric acid for absorption.
Hydrochlorothiazide25 mg daily. Thiazides enhance renal calcium reabsorption, cutting urinary calcium to protect against nephrocalcinosis and stones.
Natpara (recombinant PTH)PTH replacement for refractory cases. Restores physiologic calcium handling, lowers urinary calcium, and reduces the calcium and calcitriol requirement.
📊 Monitoring
Ionized calcium q4-6h during IV therapy, to titrate the drip and know when oral therapy has taken over.
Continuous telemetry while symptomatic: the QTc is the marker that tracks torsades risk, not the total calcium number alone.
Target serum calcium at the LOW end of normal (8.0-8.5) in chronic disease. Aiming for mid-normal drives urinary calcium losses, because without PTH the kidney cannot reabsorb what you give.
24-hour urine calcium q3-6 months (normal < 300 mg): this catches hypercalciuria before it becomes nephrocalcinosis and CKD.
Renal ultrasound annually to detect nephrocalcinosis, plus creatinine trend, since renal damage can progress while serum calcium looks perfect.
Recheck calcium in the 24-72 h window after thyroidectomy, the period in which post-surgical hypoparathyroidism declares itself.
⚠️ Pitfalls
Giving calcium without checking magnesium. Mg < 1.0 blocks both PTH secretion and PTH action, so repletion is futile until Mg is fixed. This is the classic miss.
Prescribing plain vitamin D (ergocalciferol or cholecalciferol) instead of calcitriol. Activation requires PTH-driven renal 1-alpha hydroxylation, which these patients cannot do, so only the active form works.
Assuming a normal serum calcium means the patient is safe. Without PTH the kidney wastes calcium, so chronic hypercalciuria damages kidneys despite a perfectly normal serum level.
Running calcium chloride through a peripheral IV. Extravasation causes tissue necrosis; use gluconate peripherally and reserve CaCl₂ for central access.
Over-replacing with calcitriol. Higher serum calcium means higher filtered load and more urinary calcium; back the dose down and add a thiazide when 24-hour urine calcium is high.
Missing hypocalcemia as the cause of a new seizure in a patient with DiGeorge or a recent neck operation, where a stat ionized calcium is the fastest diagnostic move.
🏥 Escalate / Refer When
Seizure, tetany, or prolonged QTc: IV calcium plus telemetry now, since these are the manifestations that kill rather than merely uncomfort.
Not controlled on calcium plus calcitriol: consider Natpara (recombinant PTH), which replaces the missing hormone rather than working around it.
Nephrocalcinosis on imaging, rising creatinine, or 24-hour urine calcium above 300 mg: add a thiazide, reduce calcitriol toward a low-normal serum calcium, restrict dietary sodium (sodium drives urinary calcium excretion), and involve nephrology.
DiGeorge syndrome: immunology consult for thymic aplasia and the associated T-cell deficiency, alongside lifelong calcium and calcitriol.
Suspected APS-1: screen for the associated adrenal insufficiency, because an unrecognized adrenal crisis is the more immediately lethal problem.
👀 Exam Signs (CHVOSTEK)
Chvostek sign, facial twitch on tapping the facial nerve.
Hyperreflexia, from neuromuscular hyperexcitability as calcium falls.
Vitals, meaning the prolonged QT interval on the monitor.
Obtundation and seizures, the severe end of the CNS spectrum.
Spasm, the Trousseau sign of carpopedal spasm with cuff inflation.
Kidney stones, from chronic hypercalciuria progressing to nephrocalcinosis.
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
EmergentEM
Burns Management
Rule of 9s for BSA estimation. Parkland formula for fluid resuscitation (4 mL × kg × %BSA burned). Major burns: ≥ 20% BSA, inhalation injury, circumferential, face/hands/genitals. Early intubation if airway concern.
🔍 Overview
Burn Classification
Depth
Appearance
Sensation
Healing
Superficial (1st)
Red, dry, no blisters (sunburn)
Painful
3–5 days, no scarring
Partial thickness (2nd)
Blisters, moist, pink/red
Very painful
Superficial: 2–3 wks. Deep: 3–8 wks, may need grafting
Full thickness (3rd)
White/brown/black, leathery, dry
Painless (nerves destroyed)
Requires excision and grafting
4th degree
Extends to muscle, bone, tendon
Painless
Amputation may be required
Rule of 9s (Adult BSA)
Head: 9%
Each arm: 9%
Anterior trunk: 18%
Posterior trunk: 18%
Each leg: 18%
Perineum: 1%
Patient's palm ≈ 1% BSA
Inhalation injury clues: singed nasal/facial hair, carbonaceous sputum, stridor, hoarseness, facial burns. Intubate early -airway edema worsens over hours. Once obstructed, intubation becomes impossible.
Electrical Burns
Type
Mechanism
Key Concerns
Low voltage (<1000V)
Household current
Can cause cardiac arrhythmias (VFib). Get ECG. Monitor 24h if abnormal.
High voltage (>1000V)
Severe deep tissue injury along current path
Damage often far worse than skin appearance. Rhabdomyolysis common → check CK, urine myoglobin, aggressive IVF for renal protection. Compartment syndrome risk → fasciotomy may be needed. Entry and exit wounds.
Lightning
Cardiac arrest (asystole), neurologic injury
Tympanic membrane rupture, cataracts. "Reverse triage" -treat those who appear dead first (cardiac arrest is often reversible with lightning).
Chemical Burns
Alkali burns (lye, cement, drain cleaner): MORE dangerous than acid. Cause liquefactive necrosis → deeper penetration. Irrigate with water for 30+ minutes.
Acid burns: Coagulative necrosis → self-limiting depth. Irrigate with water.
Hydrofluoric acid (HF): Uniquely dangerous. Fluoride binds calcium → hypocalcemia, fatal arrhythmias. Treat with topical calcium gluconate gel. IV calcium if systemic toxicity. Can be fatal even with small burns.
Key point: IRRIGATE first, remove contaminated clothing. Do NOT try to neutralize (exothermic reaction → more damage).
Burn Center Transfer Criteria: ≥20% BSA partial/full thickness, full thickness >5% BSA, face/hands/feet/genitals/perineum/major joints, electrical burns (including lightning), chemical burns with threat of cosmetic/functional impairment, inhalation injury, circumferential burns, pre-existing conditions complicating management, children (if facility lacks pediatric capability).
🚨 Management
Parkland Formula (First 24h)
4 mL × body weight (kg) × %BSA burned = total LR in 24h. Give half in first 8 hours (from time of burn, not arrival), second half over next 16 hours. Only count 2nd/3rd degree burns. Titrate to urine output 0.5–1 mL/kg/hr (adults).
Key Interventions
Airway -early intubation if inhalation injury suspected. Do NOT wait for desaturation.
Escharotomy -circumferential full-thickness burns → compartment syndrome. Limb: loss of pulse. Chest: restricted ventilation. Emergent bedside incision through eschar.
Tetanus prophylaxis
Pain control -IV opioids (burns are extremely painful)
Wound care -gentle debridement, topical antimicrobials
Transfer to burn center -≥ 20% BSA, full thickness > 5%, face/hands/feet/genitals, inhalation, electrical/chemical, children
📋 Case 1, Major Thermal Burn with Inhalation Injury
Patient: 25M pulled from house fire. Singed nasal hair, carbonaceous sputum, stridor. 35% BSA partial thickness burns.
Action:
Intubate NOW -do not wait for desaturation. Stridor + singed hair + carbonaceous sputum = inhalation injury. Airway edema will worsen rapidly.
Parkland formula: 4 × 80kg × 35% = 11,200 mL LR in 24h. Give 5,600 mL in first 8h (from time of burn).
Target UOP: 0.5–1 mL/kg/hr.
Check COHb, obtain CXR, tetanus prophylaxis, IV morphine for pain.
📋 Case 2, Electrical Burn with Rhabdomyolysis
Patient: Electrician, 220V shock to right hand, exit wound left foot. Skin burns appear small. CK 15,000. Dark urine.
Action:
Electrical burns are WORSE than they look. Deep tissue injury along current path -muscle, nerve, vessel damage far exceeds skin appearance.
Aggressive IVF -target UOP 1–2 mL/kg/hr (higher than standard burn resuscitation for myoglobinuria).
ECG monitoring × 24h -risk of cardiac arrhythmias.
Watch for compartment syndrome -check pulses, compartment pressures if concern. Fasciotomy may be needed.
Consider IV sodium bicarbonate to alkalinize urine and prevent myoglobin precipitation in renal tubules.
📋 Case 3, Hydrofluoric Acid Burn with Systemic Toxicity
Patient: Lab worker spills hydrofluoric acid on hand, small burn area. Develops tingling in hand, then cardiac monitor shows prolonged QT.
Action:
HF acid burns are life-threatening even when small. Fluoride chelates calcium → hypocalcemia → arrhythmias.
Apply topical calcium gluconate gel to affected area immediately.
Check ionized calcium (iCa) -if low, give IV calcium gluconate.
Continuous cardiac monitoring -prolonged QT, arrhythmias from hypocalcemia can be fatal.
Irrigate thoroughly with water. Do NOT attempt to neutralize the acid.
🧪 Workup
BSA estimation (Rule of 9s or Lund-Browder chart)
CBC, BMP, lactate, coags
Carboxyhemoglobin (COHb) -if enclosed-space fire (CO poisoning)
ABG -metabolic acidosis, CO levels
CXR -inhalation injury
Type and screen
Urine myoglobin -if electrical burn or rhabdomyolysis suspected
💊 Medications
Drug
Dose
Purpose
Lactated Ringer's
Parkland formula
Resuscitation fluid of choice (NOT NS -hyperchloremic acidosis risk)
Morphine (MS Contin)
0.1 mg/kg IV q2–4h
Pain -burns are extremely painful. IV only (poor absorption otherwise).
Silver Sulfadiazine (Silvadene)
Topical to wounds
Topical antimicrobial. Avoid on face (staining). Sulfa allergy caution.
Mafenide (Sulfamylon)
Topical
Penetrates eschar -used for ear burns (prevents chondritis). Painful on application. Can cause metabolic acidosis.
Tetanus prophylaxis
Tdap (or Td) 0.5 mL IM ± TIG 250 units IM
Give Tdap/Td if last booster > 5 years (dirty wound) or > 10 years (clean wound) or unknown status. Add tetanus immunoglobulin (TIG) 250 units IM for high-risk wounds (deep, contaminated, necrotic, burns) in patients with < 3 prior vaccinations or unknown status. Burns are considered tetanus-prone.
📋 On Rounds
Pimp Questions
Why do you use Lactated Ringer's instead of Normal Saline for burn resuscitation?
Burns require massive fluid volumes (Parkland formula). Large-volume NS causes hyperchloremic metabolic acidosis (dilutional, from supraphysiologic Cl⁻ concentration). LR has a more physiologic electrolyte composition. Additionally, LR contains lactate which is converted to bicarbonate by the liver, providing a mild buffer effect.
When is escharotomy indicated?
Circumferential full-thickness burns that compromise circulation or ventilation. The burned eschar is inelastic -as underlying tissue swells, pressure rises. Limb: loss of distal pulses, paresthesias, pain with passive stretch (compartment syndrome). Chest: inability to ventilate (restricted chest wall expansion). Escharotomy is a bedside procedure -longitudinal incision through eschar to release pressure.
What is the significance of carboxyhemoglobin (COHb) levels?
CO binds hemoglobin with 250× greater affinity than O₂ → left-shifts the oxyhemoglobin curve → tissue hypoxia despite "normal" PaO₂. SpO₂ is UNRELIABLE -pulse ox cannot distinguish COHb from OxyHb. COHb > 15% is significant, > 25% is severe. Treatment: 100% O₂ via NRB (half-life of COHb drops from 5h to 1h). Hyperbaric O₂ for severe cases (COHb > 25%, neurologic symptoms, pregnancy).
Why is succinylcholine contraindicated in burn patients after 48 hours?
Burns cause upregulation of extrajunctional (immature) nicotinic acetylcholine receptors across the entire muscle membrane. Succinylcholine depolarizes ALL these receptors simultaneously → massive potassium release → fatal hyperkalemia. This risk begins ~48h post-burn and lasts 1–2 years. Use rocuronium instead.
A burn patient develops dark/tea-colored urine. What do you suspect and how do you treat?
Myoglobinuria from rhabdomyolysis (especially electrical burns or deep thermal burns). Myoglobin is nephrotoxic → can cause ATN and AKI. Treat: aggressive IV LR (target UOP 1–2 mL/kg/hr for myoglobinuria -higher than standard burn resuscitation), consider IV sodium bicarbonate to alkalinize urine (prevents myoglobin precipitation in tubules), monitor CK and renal function. Avoid mannitol (controversial).
⚡ Summary
Airway First, and Early
Singed nasal or facial hair, carbonaceous sputum, hoarseness, stridor and facial burns mean intubate now.Airway edema worsens over hours and once the airway obstructs, intubation becomes impossible, and a surgical airway through a burned neck is a very poor alternative. Err toward early intubation: extubating an unnecessary tube the next day is trivial by comparison.
Classify the Depth
Superficial (first degree): red, dry, painful, heals in 3 to 5 days without scarring, and is excluded from the burn surface area calculation. Partial thickness (second): blistered, moist, very painful. Full thickness (third): white or leathery, dry and painless because the nerve endings are destroyed, always needing excision and grafting. Painlessness is a sign of depth, not of a minor burn.
Estimate the Area
Rule of 9s: head 9%, each arm 9%, each leg 18%, anterior trunk 18%, posterior trunk 18%, perineum 1%. The patient's palm including fingers is about 1% and is the practical tool for scattered burns. Overestimating the area over-resuscitates, which is the commonest error and causes its own harm.
Parkland, Then Titrate to Urine Output
4 mL × kg × %BSA of lactated Ringer over 24 h, with half in the first 8 h from the time of injury, not from arrival.The formula is a starting estimate, not a prescription: titrate to a urine output of 0.5 mL/kg/h in adults and 1 mL/kg/h in children. Over-resuscitation causes abdominal compartment syndrome, pulmonary edema and conversion of partial to full thickness burns.
Circumferential Burns Need Escharotomy
A circumferential full-thickness burn of a limb acts as a tourniquet as edema develops, so watch for loss of distal pulses, worsening pain and rising compartment pressures. A circumferential chest burn restricts ventilation and shows up as rising airway pressures. Escharotomy is a bedside procedure and should not wait for transfer.
Do Not Miss Carbon Monoxide and Cyanide
Pulse oximetry is falsely normal in carbon monoxide poisoning, because carboxyhemoglobin absorbs light like oxyhemoglobin. Get a co-oximetry level and give 100% oxygen, with hyperbaric therapy considered for severe poisoning or pregnancy. Suspect cyanide in an enclosed-space fire with a persistent lactic acidosis and normal oxygenation, and treat with hydroxocobalamin.
Electrical and Chemical Burns Break the Usual Rules
Electrical injury damages far more tissue than the skin suggests: expect rhabdomyolysis, so run higher fluids and target a larger urine output, monitor for arrhythmia, and look for compartment syndrome and associated fractures from tetanic contraction. Chemical burns: brush off dry powder first, then irrigate copiously with water; do not neutralize, since the reaction is exothermic and causes further injury. Hydrofluoric acid needs calcium gluconate and causes life-threatening hypocalcemia.
Know Who Gets Transferred
Burn center criteria: partial or full thickness of 20% BSA or more, full thickness above 5%, any burn to face, hands, feet, genitals, perineum or major joints, electrical and lightning injury, significant chemical burns, inhalation injury, and burns in patients with major comorbidity. Also: keep the patient warm, since burns lose thermoregulation and hypothermia worsens coagulopathy. Give tetanus prophylaxis, provide adequate analgesia, and do not give prophylactic systemic antibiotics, which select resistance without preventing burn wound infection.
Core temp < 35°C. Mild (32–35°C): shivering. Moderate (28–32°C): loss of shivering, confusion, Osborn waves. Severe (< 28°C): VF risk, appears dead. Warm before declaring death. Active rewarming for moderate-severe.
Active external rewarming (Bair Hugger, warm packs to axillae/groin). Warm IV fluids 40–42°C.
Severe
< 28°C
Coma, areflexia, VF risk, fixed dilated pupils, appears dead
Active core rewarming (warm humidified O₂, peritoneal/pleural lavage, ECMO). Withhold meds until ≥ 30°C.
Profound
< 24°C
Asystole, no vital signs. May still be salvageable with rewarming.
ECMO/cardiopulmonary bypass (gold standard). Prolonged CPR. Do NOT declare death.
"No one is dead until they are warm and dead." Do NOT declare death until core temp ≥ 32°C and rewarming efforts have failed. Hypothermia is neuroprotective -full recovery has occurred after prolonged cold-water submersion.
Moderate–severe. Adjunct to other rewarming methods.
Modest contribution (~0.5°C/hr alone)
Warm humidified O₂ (42–46°C via ETT or NRB)
Moderate–severe. Active core rewarming adjunct.
1–1.5°C/hr
Peritoneal/pleural lavage (42°C warm saline)
Severe (< 28°C) when ECMO unavailable. More effective than bladder lavage.
2–4°C/hr
ECMO / cardiopulmonary bypass
Severe hypothermic cardiac arrest. Gold standard.
5–10°C/hr
Cardiac Arrest in Hypothermia
ECMO/CPB -gold standard rewarming for VF arrest in hypothermia. Rewarms at 5–10°C/hr.
Continue CPR -may need prolonged resuscitation
Defibrillation: May attempt up to 3 shocks if temp < 30°C. If unsuccessful, defer further shocks until core temp ≥ 30°C.
Medications: Withhold vasopressors and antiarrhythmics until core temp ≥ 30°C (drugs don't work and accumulate in cold circulation)
Drowning Management
Rescue breathing is the priority -drowning is a hypoxic event. Begin ventilation as soon as possible, even in the water if safe.
Cervical spine precautions -maintain inline stabilization if diving injury, trauma, or mechanism suggests c-spine injury. However, routine c-spine immobilization in all drowning victims is NOT supported.
Warm IV fluids -most drowning victims are hypothermic. Start warm NS/LR (40–42°C). Treat concomitant hypothermia aggressively per rewarming protocols above.
Pulmonary edema -watch for delayed pulmonary edema 24–48 hours post-submersion. Aspirated water disrupts surfactant and damages alveolar epithelium. CXR may be initially normal but deteriorate.
Freshwater vs saltwater -freshwater is hypotonic (washes out surfactant, absorbed into circulation). Saltwater is hypertonic (pulls fluid into alveoli). Clinical management is the same for both.
Prognostication:
Submersion time -strongest predictor. > 25 min submersion in warm water = very poor prognosis.
Water temperature -cold water (< 6°C) is neuroprotective. Full neurologic recovery reported after > 60 min submersion in ice water (especially children).
Age -children have better outcomes than adults due to higher surface-area-to-body-mass ratio → faster cooling → more neuroprotection.
CPR duration and initial rhythm -faster ROSC = better outcome. VF is better than asystole.
Cold-water drowning in children: Aggressive rewarming and prolonged resuscitation are warranted. The combination of rapid cooling + diving reflex can provide profound neuroprotection. Do not stop early.
🧪 Workup
Core temperature -rectal or esophageal probe (NOT oral/tympanic -inaccurate in hypothermia)
TSH, cortisol -rule out myxedema/adrenal crisis as cause
💊 Medications
Intervention
Details
Notes
Warm IV NS/LR (40–42°C)
250–500 mL boluses
Use fluid warmer. Contributes modestly to rewarming.
Warm humidified O₂
42–46°C via ETT or NRB
Active core rewarming adjunct
Warm bladder lavage
42°C NS via 3-way Foley
Moderate core rewarming
Warm peritoneal lavage
42°C NS via peritoneal catheter
More effective than bladder lavage
ECMO
Venoarterial (VA-ECMO)
Gold standard for severe hypothermic cardiac arrest. Rewarms 5–10°C/hr.
Withhold IV medications until core temp ≥ 30°C. Drugs are ineffective in cold circulation, don't metabolize, and accumulate → risk of toxicity when patient rewarms.
📋 On Rounds
Pimp Questions
What are Osborn (J) waves?
Positive deflection at the J point (junction of QRS and ST segment) on ECG, pathognomonic for hypothermia. Appear at core temp < 32°C, increase in amplitude as temperature drops. Also called "J waves" or "hypothermic hump." Resolve with rewarming. Not an indication for anti-arrhythmic therapy.
Why is K⁺ > 12 mEq/L considered non-survivable in hypothermia?
Severe hyperkalemia (> 12) in hypothermia indicates massive cell lysis and tissue death -the cells have been irreversibly damaged by ice crystal formation. This level of intracellular potassium release means the patient likely has extensive organ damage incompatible with survival, even with successful rewarming. It is one of the few criteria used to guide termination of resuscitation in hypothermic arrest.
📋 Case 1, Moderate Hypothermia (Found Down)
Patient: 78M found on his kitchen floor by a neighbor. Last seen well 18 hours ago. Confused, minimally responsive. Temp: 30.1°C (rectal). HR 38 (bradycardia). BP 88/54. RR 8.
ECG: Sinus bradycardia with Osborn (J) waves at the J-point. QTc prolonged. No VF.
Remove all wet/cold clothing. Dry skin. Wrap in warm blankets.
Active external rewarming: Bair Hugger forced-air warming blanket. Warm packs to axillae and groin (high-flow areas). Target: rewarm the trunk first.
Warm IV fluids: NS at 40–42°C via fluid warmer, 250–500 mL bolus. Correct hypoglycemia with D50W.
Do NOT treat bradycardia or AF with medications, the arrhythmia is from hypothermia and will resolve with rewarming.
Check TSH and cortisol, hypothyroidism and adrenal insufficiency are precipitating causes of hypothermia in the elderly.
K⁺ 5.8: Monitor closely. Expected to improve with rewarming. K⁺ >12 = non-survivable (massive cell lysis); K⁺ 5.8 is compatible with survival.
Serial core temps q1h (esophageal or rectal probe) and continuous telemetry during rewarming.
Teaching point: In elderly patients found down, always measure core temperature. Oral/tympanic temps are unreliable, use rectal or esophageal probe. Check TSH and cortisol; hypothyroidism is a classic precipitant of hypothermia in the elderly.
📋 Case 2, Severe Hypothermia with VF Arrest
Patient: 32M found unresponsive in a snowbank by ski patrol. No pulse, no respirations. Estimated outdoor exposure 2+ hours. Initial core temp: 24°C.
In the field: CPR initiated immediately. AED delivered 1 shock, rhythm remained VF. Patient transported to ED with ongoing CPR.
In the ED:
Confirm core temperature with esophageal probe: 24°C, profound hypothermia
Continue CPR, do not stop. Hypothermia is neuroprotective; viable patients have been resuscitated after >6 hours of CPR.
Attempt defibrillation × 3 total (have already done 1 in field). If unsuccessful at <30°C, defer further shocks until core temp ≥30°C.
Withhold epinephrine and amiodarone until core temp ≥30°C, drugs accumulate and are ineffective in cold circulation.
ACTIVATE ECMO TEAM STAT, VA-ECMO is the gold standard for hypothermic cardiac arrest. Can rewarm at 5–10°C/hr.
K⁺: 7.2, compatible with survival. Proceed with rewarming.
ECMO initiated. Core temp rises over 90 minutes to 32°C → spontaneous ROSC, VF terminates. Patient extubated day 3. Full neurologic recovery.
Teaching point: K⁺ >12 mEq/L = non-survivable (massive cell lysis). This patient's K⁺ 7.2 meant the cells were still viable, aggressive ECMO rewarming was warranted. "No one is dead until warm and dead."
📋 Case 3, Cold-Water Drowning in a Child
Patient: 7F falls through ice on a frozen pond. Submerged approximately 45 minutes before rescue. Core temp on EMS arrival: 22°C. No pulse. Pupils fixed and dilated. Cyanotic.
EMS: CPR initiated. Bystanders attempted rescue within 5 minutes of submersion.
ED Management:
Core temp 22°C, do NOT declare death. "No one is dead until warm and dead."
Fixed dilated pupils, absent reflexes: all expected findings at this temperature. Do not use these as markers of irreversibility in hypothermia.
ECMO activation, VA-ECMO for hypothermic cardiac arrest. Children have better outcomes than adults (faster cooling via diving reflex + higher surface-area-to-mass ratio).
Warm via ECMO, core temp rises to 36°C over 2 hours. ROSC at core temp 30°C (sinus bradycardia → normal sinus rhythm with rewarming).
Post-resuscitation care: Targeted temperature management at 33–36°C × 24h. ICU monitoring. Neurologic exam serially.
Day 5: Extubated. Neurologically intact. Discharged day 10.
Teaching point: The mammalian diving reflex + rapid hypothermic cooling in ice water provides profound neuroprotection in children. The protective combination: apnea + bradycardia + peripheral vasoconstriction + near-freezing temperatures drops oxygen consumption to near zero. Full neurologic survival after prolonged submersion is well-documented in pediatric cold-water drowning, never stop early.
⚡ Summary
Stage It by Core Temperature
Mild 32 to 35°C: still shivering, tachycardic. Moderate 28 to 32°C: shivering stops, confusion to stupor, bradycardia, Osborn (J) waves. Severe below 28°C: coma, areflexia, fixed dilated pupils, high VF risk. Profound below 24°C: asystole. Loss of shivering is the key transition, because the patient can no longer generate their own heat and passive rewarming stops working.
Match the Rewarming to the Stage
Mild → passive external (dry clothes, blankets, warm room, 0.5 to 2°C/h). Moderate → active external (forced-air warmer, packs to axillae and groin, 1 to 2°C/h). Severe → active core (warm humidified oxygen, warm IV fluids, peritoneal or pleural lavage at 2 to 4°C/h). Hypothermic arrest → ECMO or bypass, which is the gold standard at 5 to 10°C/h.
Nobody Is Dead Until Warm and Dead
Do not declare death until the core temperature is at least 32°C and rewarming has failed. Hypothermia is neuroprotective, and intact neurological recovery has followed prolonged cold-water submersion, so the cold patient who looks dead is resuscitated first and pronounced later.
Handle Them Gently
The severely hypothermic myocardium is irritable and will fibrillate from rough handling, so move the patient carefully and avoid unnecessary jostling and non-essential line placement.
Drugs and Shocks Behave Differently in the Cold
Withhold IV medications until the core temperature reaches 30°C: cold circulation makes them ineffective and they are not metabolized, so they accumulate and become toxic on rewarming. Limit defibrillation to a maximum of 3 attempts below 30°C, then rewarm before trying again.
Rewarming Has Its Own Complications
Afterdrop: cold peripheral blood returning centrally drops the core temperature further, which is why the trunk is rewarmed before the limbs. Rewarming collapse: peripheral vasodilation unmasks a profound volume deficit, so anticipate hypotension and give warmed fluids. Also watch potassium and glucose, which shift as the patient warms.
Drowning Is a Hypoxia Problem
Ventilation comes first, not compressions, because the arrest is asphyxial. Fresh versus salt water does not change management. Anyone symptomatic needs 4 to 8 h of observation, since pulmonary injury can declare itself late; the truly asymptomatic patient with a normal exam and saturation can go home.
Push Longer in Cold-Water Drowning, Especially in Children
Rapid cooling plus the diving reflex can be profoundly neuroprotective, so aggressive rewarming and prolonged resuscitation are warranted and the usual stopping rules do not apply. Do not stop early.
Neurologic symptoms -headache, confusion, dizziness, stroke, coma
Do NOT transfuse pRBCs before plasmapheresis in paraprotein hyperviscosity -adding RBCs to already viscous blood will worsen sludging and can precipitate stroke or MI.
Pathophysiology
Excess paraprotein (most commonly IgM) increases serum viscosity, leading to sludging of blood in the microvasculature. This causes hypoperfusion and end-organ damage affecting the brain, eyes, and mucosal surfaces. IgM is the most common cause because it exists as a pentamer (~900 kDa) -five immunoglobulin subunits linked together -making it far larger than IgG (~150 kDa) or IgA (~160 kDa monomer). Even modest concentrations of IgM dramatically increase viscosity. IgA can also cause hyperviscosity because it tends to polymerize, but this is less common. IgG rarely causes hyperviscosity because it remains a small monomer. The relationship between immunoglobulin concentration and viscosity is exponential, not linear -small increases in paraprotein at high levels cause disproportionate rises in viscosity. Additionally, paraproteins interfere with platelet aggregation and clotting factor function, contributing to the bleeding diathesis.
Clinical Triad -Detailed Findings
Category
Specific Findings
Mechanism
Mucosal Bleeding
Epistaxis (most common), gingival bleeding, GI bleeding, menorrhagia, purpura
Paraprotein coats platelets (impaired aggregation) and interferes with fibrin polymerization and clotting factors
📋 Case 1, Waldenström with Epistaxis and Visual Changes
Patient: 68M with known Waldenström macroglobulinemia presents with recurrent epistaxis and blurred vision over the past 3 days. On exam, bilateral retinal hemorrhages and "sausage-link" retinal veins on fundoscopy.
Emergent plasmapheresis -viscosity 8.2 is critically elevated. Do NOT wait for heme/onc consult to initiate.
Aggressive IV NS -hydration to reduce viscosity while awaiting pheresis.
Do NOT transfuse pRBCs -will worsen sludging at this viscosity level.
Serial fundoscopic exams after pheresis to confirm resolution of retinal findings.
After viscosity controlled, discuss initiation of rituximab-based chemotherapy with heme/onc.
📋 Case 2, Multiple Myeloma (IgA) with Confusion
Patient: 72F with IgA multiple myeloma on lenalidomide presents with progressive confusion and severe headache over 24 hours. Family reports increasing somnolence.
Plasmapheresis -symptomatic hyperviscosity with neurologic findings. IgA less commonly causes hyperviscosity than IgM, but this patient's IgA is polymerizing.
Neuro checks q1h -monitor for progression to obtundation or coma.
CT head -rule out intracranial hemorrhage or stroke as alternative/concurrent diagnosis.
Discuss chemotherapy adjustment with heme/onc -current regimen not controlling disease.
Monitor renal function -Cr elevation may be from hyperviscosity-related renal hypoperfusion or light-chain nephropathy.
📋 Case 3, New Waldenström with DVT and Hyperviscosity
Patient: 55M presents with left leg DVT and is incidentally found to have IgM 4.5 g/dL on workup. Reports fatigue and "haziness" in vision for weeks. Fundoscopy shows early sausage-link changes. Serum viscosity 4.8 cP.
Action:
New diagnosis of Waldenström macroglobulinemia with symptomatic hyperviscosity. Bone marrow biopsy for confirmation.
Plasmapheresis -symptomatic with visual changes and viscosity 4.8 cP.
Anticoagulation for DVT -heparin drip (monitor closely given bleeding risk from paraprotein).
Avoid pRBC transfusion before viscosity is reduced -even if Hgb is low, transfusion can precipitate stroke/MI.
Rituximab-based therapy (e.g., bendamustine-rituximab or ibrutinib) for definitive treatment. Note: rituximab can cause transient "IgM flare" (paradoxical IgM rise) -pheresis may need to be repeated.
🚨 Management
Emergent Treatment
Plasmapheresis (plasma exchange) -first-line for symptomatic hyperviscosity. Removes paraprotein directly. 1–2 sessions typically provide rapid relief.
Leukostasis: Leukapheresis + hydroxyurea + start definitive chemotherapy. IV fluids for dilution.
Polycythemia: Phlebotomy to target Hct < 45%.
IV fluids -aggressive hydration to reduce viscosity
Avoid diuretics -worsens hemoconcentration
Avoid pRBC transfusion -until viscosity is reduced (except for life-threatening anemia)
🧪 Workup
Serum viscosity -normal 1.4–1.8 cP. Symptoms typically at > 4 cP. Emergency at > 5–6 cP.
SPEP + immunofixation -identify paraprotein
CBC with diff -WBC count (leukostasis), Hct (polycythemia)
Coagulation studies -may be abnormal (paraprotein interference)
💊 Medications
Intervention
Details
Notes
Plasmapheresis
1–1.5 plasma volumes per session
First-line. 1–2 sessions for symptom relief. Bridge to chemotherapy.
IV NS
Aggressive hydration
Dilute viscous blood. Avoid dehydration.
Hydroxyurea (Hydrea)
50–100 mg/kg/day
Leukostasis -cytoreduction while awaiting chemo
Phlebotomy
Target Hct < 45%
Polycythemia vera
📋 On Rounds
Pimp Questions
Why is IgM the most common cause of hyperviscosity among paraproteins?
IgM exists as a pentamer -5 immunoglobulin units linked together, making it the largest antibody (~900 kDa vs 150 kDa for IgG). This enormous size dramatically increases serum viscosity even at relatively modest concentrations. IgA can also cause hyperviscosity because it polymerizes, but IgG rarely does. This is why Waldenström (IgM-producing) causes hyperviscosity much more commonly than myeloma (usually IgG).
What is the difference between hyperviscosity from paraproteins vs leukostasis?
Paraprotein hyperviscosity: Increased serum viscosity from immunoglobulin. Treated with plasmapheresis. Leukostasis: NOT truly viscosity -it's mechanical plugging of microvasculature by large, sticky blast cells (AML blasts are stickier than ALL). WBC > 100K in AML is concerning. Treated with leukapheresis + hydroxyurea + emergent chemo. Both present similarly (CNS, pulmonary, bleeding), but treatment is different.
Why should you avoid RBC transfusion before plasmapheresis in hyperviscosity?
In paraprotein-mediated hyperviscosity, the serum is already abnormally viscous from excess immunoglobulin. Transfusing packed RBCs increases the cellular fraction of blood (raises hematocrit) without removing any paraprotein, causing a dramatic further rise in whole-blood viscosity.
Why is IgM the most common immunoglobulin causing hyperviscosity?
IgM circulates as a pentamer -five immunoglobulin subunits linked together by J chains and disulfide bonds, creating a massive molecule of approximately 900 kDa. Compare this to IgG at ~150 kDa (monomer) or IgA at ~160 kDa (monomer, though it can dimerize to ~320 kDa). The enormous hydrodynamic radius of the IgM pentamer means it dramatically increases the viscosity of plasma even at relatively low concentrations.
⚡ Summary
The Triad
Mucosal bleeding, visual changes and neurologic symptoms. Epistaxis is the commonest bleed; the visual complaint ranges from blurring to sudden loss; the neurology runs from headache and vertigo to confusion, seizure and coma. Any two of the three in a patient with a paraprotein or an extreme cell count is the diagnosis until disproven.
Know Which Diseases Cause It
Waldenstrom macroglobulinemia is number one, because IgM is a pentamer and is by far the most viscous molecule. Multiple myeloma is less common, about 2 to 5% of cases, and then usually IgA (which polymerizes) rather than IgG. Leukostasis with WBC above 100,000 in AML or above 200,000 to 300,000 in lymphoid leukemias. Polycythemia vera with a hematocrit above 60 to 65%.
Look at the Fundus
Dilated, segmented retinal veins, the 'sausage-link' or 'boxcar' appearance, with hemorrhages, exudates and papilledema.This is the fastest bedside confirmation available and it can be done before any laboratory result returns.
Confirm and Quantify
Serum viscosity, normal 1.4 to 1.8 centipoise; symptoms usually appear above 4 to 5. Send serum protein electrophoresis with immunofixation and free light chains, a CBC with differential and a smear (look for rouleaux), and a type and screen. Treat on the clinical picture rather than waiting for the viscosity result, which is often a send-out.
Plasmapheresis Is the Emergency Treatment
It removes the paraprotein directly and symptoms improve within hours.It works best for IgM, which is largely intravascular, so a single session removes most of it. It is a temporizing measure only: without treating the underlying clone, viscosity returns within days.
The Transfusion Trap
Do not transfuse red cells before plasmapheresis in paraprotein hyperviscosity. Adding red cells to already sludging blood raises viscosity further and can precipitate stroke or myocardial infarction. The anemia is largely dilutional, so the measured hemoglobin overstates the problem. If transfusion is unavoidable, give it during or after apheresis.
Match the Procedure to the Cell Line
Paraprotein → plasmapheresis. Leukostasis → leukapheresis plus urgent cytoreduction with hydroxyurea or induction chemotherapy. Polycythemia → therapeutic phlebotomy.Plasmapheresis does nothing for a cellular cause, and confusing the two loses hours the patient does not have.
Then Treat the Disease Underneath
Rituximab-based therapy for Waldenstrom, but be aware of the IgM flare: rituximab transiently raises IgM and can worsen viscosity, so plasmapherese first and consider deferring rituximab in the first cycle. Anti-myeloma therapy for myeloma, cytoreduction for leukostasis with tumor lysis prophylaxis, and cytoreductive therapy plus aspirin for polycythemia vera.
RoundsRx Infographic Series · #162 · Hematology · PDF 141 KB
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HEME / ONC · One Pager
Hyperviscosity Syndrome
An emergency. Bleeding, blurred vision, and confusion in a patient with a paraprotein means the blood is too thick to perfuse the brain and retina. Plasmapheresis is the definitive move, and pRBCs before pheresis can kill.
🚨 The Classic Triad
Mucosal bleeding: epistaxis (most common), gingival bleeding, GI bleeding, menorrhagia, purpura. The paraprotein coats platelets (impaired aggregation) and interferes with fibrin polymerization and clotting factors, so PT/PTT and thrombin time can be prolonged with no primary coagulopathy.
Visual changes: blurred vision, diplopia, visual loss. Fundoscopy shows "sausage-link" retinal veins (alternating dilated and constricted segments), Roth spots, flame-shaped retinal hemorrhages, papilledema, cotton-wool spots. Hyperviscous blood distends the retinal veins and causes stasis, leading to retinal ischemia and hemorrhage.
Neurologic symptoms: headache, dizziness, vertigo, confusion, somnolence, obtundation, hearing loss, ataxia, stroke, coma. Cerebral microvascular sludging causes hypoperfusion that can progress to frank infarction, which is why this is time-sensitive.
Do the fundoscopic exam on every suspected case. The findings are pathognomonic, they are available at the bedside before the viscosity result comes back, and they resolve after plasmapheresis so they also serve as your response marker.
⚡ Causes, Most Common First
Waldenström macroglobulinemia, the #1 cause. IgM paraprotein; the large pentamer is the most viscous immunoglobulin. Symptoms appear at IgM > 3 g/dL.
Multiple myeloma, less common, about 2–5% of MM cases. IgA > IgG because IgA polymerizes; IgG rarely does this because it stays a small monomer.
Leukostasis: WBC > 100K in AML, or > 200–300K in CLL/ALL. This is not true viscosity, it is mechanical plugging of the microvasculature by large sticky blast cells (AML blasts are stickier than ALL), and that is why the treatment differs.
Polycythemia vera: Hct > 60–65% with RBC sludging.
Why IgM dominates: IgM circulates as a pentamer (~900 kDa) versus IgG at ~150 kDa and IgA at ~160 kDa as a monomer. The relationship between immunoglobulin concentration and viscosity is exponential, not linear, so small increases at high levels cause disproportionate rises in viscosity.
🚨 Management, Step by Step
1
Recognize at the bedside: triad symptoms plus fundoscopy. Do not wait for the viscosity level to act if the retina and the neuro exam already tell you.
2
Send serum viscosity: normal 1.4–1.8 cP, symptomatic typically > 4 cP, emergency > 5–6 cP. It must be ordered specifically, it is not part of routine labs, so it will not appear unless you ask for it.
3
Emergent plasmapheresis (plasma exchange), 1–1.5 plasma volumes per session. First-line for symptomatic paraprotein hyperviscosity because it removes the paraprotein directly; 1–2 sessions typically give rapid relief. Do not wait for the heme/onc consult to initiate.
4
Aggressive IV normal saline to dilute viscous blood while awaiting pheresis. Avoid diuretics, they worsen hemoconcentration and make the viscosity worse.
5
Treat by mechanism, not by label: leukostasis gets leukapheresis + hydroxyurea + emergent chemotherapy plus IV fluids, since pheresis of plasma does nothing for cell plugging. Polycythemia gets phlebotomy to a target Hct < 45%.
6
Bridge to definitive therapy. Plasmapheresis buys time, it does not treat the clone. Once viscosity is controlled, start rituximab-based therapy for Waldenström or adjust the myeloma regimen with heme/onc.
💊 Key Interventions
Plasmapheresis1–1.5 plasma volumes per session; first-line, 1–2 sessions for symptom relief, bridge to chemotherapy
IV normal salineaggressive hydration to dilute viscous blood; avoid dehydration and avoid diuretics
Leukapheresisfor leukostasis, removes the plugging blasts that plasma exchange cannot touch
Hydroxyurea (Hydrea)50–100 mg/kg/day; cytoreduction in leukostasis while awaiting definitive chemotherapy
Phlebotomytarget Hct < 45% in polycythemia vera
Rituximab-based therapydefinitive treatment for Waldenström after viscosity is controlled; can cause a transient "IgM flare"
📊 Workup and Numbers
Serum viscosity: normal 1.4–1.8 cP, symptoms > 4 cP, emergency > 5–6 cP. The definitive measurement, and it must be ordered specifically.
SPEP with immunofixation: M-spike plus isotype (IgM, IgA, IgG). A large M-spike correlates with viscosity.
Quantitative immunoglobulins: IgM > 3 g/dL almost always causes symptoms in Waldenström; other Ig levels may be suppressed.
UPEP (24-hr urine): Bence Jones protein, supports myeloma and gauges renal light-chain burden.
CBC with peripheral smear:rouleaux formation (RBCs stacked like coins) is classic. Anemia may be dilutional or from marrow infiltration.
Coagulation studies: prolonged PT/PTT and thrombin time from paraprotein interference, not from factor deficiency.
Serial fundoscopy after pheresis to confirm the retinal findings are resolving, which is your objective evidence the viscosity actually came down.
⚠️ Pitfalls
Transfusing pRBCs before plasmapheresis. This is the classic killer. Adding RBCs raises the cellular fraction without removing any paraprotein, causing a dramatic further rise in whole-blood viscosity, which worsens sludging and can precipitate stroke or MI. Hold transfusion until viscosity is reduced, even if the Hgb looks low.
Giving diuretics for the "volume overloaded" appearance. They worsen hemoconcentration and drive viscosity up.
Not ordering serum viscosity, then concluding the labs are unremarkable. It is not on any routine panel.
Treating leukostasis with plasmapheresis. Leukostasis is cell plugging, not plasma viscosity; it needs leukapheresis, hydroxyurea, and emergent chemotherapy. Both syndromes look alike (CNS, pulmonary, bleeding) but the therapy differs.
Forgetting the rituximab "IgM flare." Rituximab can cause a paradoxical transient rise in IgM in Waldenström, so pheresis may need to be repeated.
Assuming a normal PT/PTT excludes bleeding risk, or assuming an abnormal one means DIC. The paraprotein itself interferes with platelet function and fibrin polymerization.
Any neurologic finding (confusion, somnolence, focal deficit): pheresis plus neuro checks q1h to catch progression to obtundation or coma, and CT head to rule out intracranial hemorrhage or stroke as an alternative or concurrent diagnosis.
Sausage-link retinal veins or new visual loss: retinal ischemia is already happening, treat as emergent.
Rising creatinine: may reflect hyperviscosity-related renal hypoperfusion or light-chain nephropathy; both change urgency and both need heme/onc input.
New paraprotein without a known diagnosis: bone marrow biopsy for confirmation once the patient is stabilized, not before pheresis.
Concurrent thrombosis: anticoagulate but monitor closely, because the same paraprotein that causes clotting risk also causes a bleeding diathesis.
DM in adults requires age-appropriate malignancy screening. Anti-TIF1-γ antibody is specifically associated with malignancy-associated DM. Screen with CT chest/abdomen/pelvis, mammogram, colonoscopy, and pelvic exam.
Inclusion Body Myositis (IBM)
Feature
Inclusion Body Myositis
Age
>50 years. Most common inflammatory myopathy in elderly.
How do you distinguish myositis from steroid myopathy during treatment?
This is a critical clinical challenge. Both cause proximal weakness. Myositis flare: CK is elevated/rising, inflammatory markers up. Steroid myopathy: CK is NORMAL, no inflammatory markers. Steroid myopathy is painless. If CK is normal but weakness persists/worsens, consider reducing steroids. If CK is rising, the myositis is active and steroids may need to be increased or a steroid-sparing agent added.
What is antisynthetase syndrome?
A clinical syndrome associated with anti-aminoacyl-tRNA synthetase antibodies (most commonly anti-Jo-1). Features: (1) ILD (interstitial lung disease -often the dominant and most life-threatening feature), (2) Inflammatory myopathy, (3) Mechanic's hands (cracked, rough skin on palms/fingers), (4) Arthritis, (5) Raynaud phenomenon, (6) Fever. ILD drives prognosis -PFTs and CT chest are essential at diagnosis.
How do you differentiate DM/PM from inclusion body myositis?
IBM: age >50, ASYMMETRIC weakness (unlike DM/PM which is symmetric), involves DISTAL muscles (finger flexors, wrist flexors -"can't make a fist"), quadriceps atrophy ("falls going downstairs"), CK only mildly elevated or normal, does NOT respond to steroids or immunosuppression. Biopsy: rimmed vacuoles + amyloid. Most common inflammatory myopathy in elderly men.
What antibody is most associated with cancer in dermatomyositis?
Anti-TIF1-γ (anti-p155/140). This antibody has the strongest association with malignancy-associated DM. Patients with anti-TIF1-γ need intensive cancer screening: CT chest/abdomen/pelvis, mammogram, colonoscopy, pelvic exam, and age-appropriate screening. Some guidelines recommend repeating screening annually for 3–5 years.
RoundsRx Licensed Content - Unauthorized Use Prohibited⚡ Summary
The Shared Feature
Proximal, symmetric, progressive muscle weakness: difficulty rising from a chair, climbing stairs and lifting the arms overhead. Weakness rather than pain is the complaint, and a patient whose main symptom is muscle pain with normal strength usually has something else.
Dermatomyositis Is Recognized by the Skin
Heliotrope rash, violaceous discoloration of the eyelids with periorbital edema. Gottron papules over the knuckles (the extensor surfaces, which is what distinguishes them from the lupus rash that spares them). Also the shawl and V signs, mechanic's hands, periungual telangiectasia and calcinosis. Polymyositis has no skin findings.
Confirm It in Four Steps
CK, aldolase, LDH and transaminases raised (a raised AST and ALT from muscle is often mistaken for liver disease). EMG shows an irritable myopathy. MRI identifies edema and the right site to biopsy. Muscle biopsy is definitive.Histology separates them: dermatomyositis shows perimysial inflammation with perifascicular atrophy, a complement-mediated microangiopathy; polymyositis shows endomysial CD8 T cells invading intact fibers.
Screen Adults With DM for Cancer
Dermatomyositis carries a strong malignancy association, and the myositis can precede the cancer by months.Anti-TIF1-gamma antibody specifically marks malignancy-associated disease.Do age-appropriate screening plus CT chest, abdomen and pelvis, mammography, colonoscopy and a pelvic examination, repeated over the first few years. Ovarian, lung, breast, gastrointestinal and lymphoma are the usual suspects.
Let the Antibodies Predict the Complications
Anti-Jo-1 and the other antisynthetases mean antisynthetase syndrome: interstitial lung disease, arthritis, mechanic's hands, Raynaud and fever. Anti-MDA5 means rapidly progressive ILD, often with little muscle involvement and normal CK, and it carries high mortality, so it needs aggressive early treatment. Anti-Mi-2 predicts classic skin disease and a good treatment response.
Screen the Lungs and the Swallow
Interstitial lung disease is the leading cause of death, so get PFTs with DLCO and a high-resolution CT at baseline, not only when the patient is breathless. Dysphagia from pharyngeal and esophageal muscle involvement causes aspiration and predicts a worse outcome, so ask about it directly and get a swallow evaluation.
Treat With Steroids Plus a Sparing Agent From the Start
Prednisone 1 mg/kg/day, tapering slowly over months.Add methotrexate or azathioprine early rather than waiting for steroid failure, because the required steroid course is long and the toxicity is what limits it. IVIG for refractory disease, severe dysphagia and for dermatomyositis skin disease; rituximab and mycophenolate for resistant cases, mycophenolate being preferred where there is ILD. Add sun protection and hydroxychloroquine for the rash, plus physical therapy from the outset, and PJP prophylaxis with prolonged high-dose steroids.
Consider Inclusion Body Myositis in the Non-Responder
Older than 50, slowly progressive, asymmetric, with distinctive involvement of finger flexors and quadriceps.It does not respond to immunosuppression, so a patient labeled as refractory polymyositis often has IBM instead. Biopsy shows rimmed vacuoles. Also exclude the commoner mimics before committing to long-term steroids: statin myopathy (including anti-HMGCR immune-mediated necrotizing myopathy, which does respond to treatment), hypothyroidism, and hereditary myopathy.
RoundsRx Infographic Series · #166 · Rheumatology · PDF 146 KB
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RHEUMATOLOGY · One Pager
Dermatomyositis & Polymyositis
Proximal, symmetric, progressive weakness with a high CK. The skin decides DM vs PM, the antibody tells you what else to look for, and in adult DM that means looking for cancer.
🧪 Skin Findings: What Separates DM from PM
Heliotrope rash: purple/lilac discoloration of the eyelids, often with periorbital edema. Pathognomonic for DM.
Gottron papules: erythematous/violaceous papules over MCP, PIP, DIP joints and knuckles. Pathognomonic.
Gottron sign: flat erythematous patches over elbows, knees, medial malleoli (a patch, not a papule).
Mechanic's hands: rough, cracked, hyperkeratotic skin on the radial fingers. Points you toward antisynthetase syndrome, so check PFTs.
Polymyositis: no skin findings at all. Histology also splits them: DM is perimysial with perifascicular atrophy, PM is endomysial with CD8+ T cells invading fibers.
⚡ Myositis Antibodies: What Each Predicts
Anti-TIF1-γ (anti-p155/140): strongest association with malignancy-associated DM. A positive result changes the workup, not just the label: it triggers intensive cancer screening.
Anti-Jo-1:antisynthetase syndrome, ILD + inflammatory myopathy + mechanic's hands + arthritis + Raynaud + fever. The ILD, not the myopathy, drives prognosis.
Anti-Mi-2, anti-MDA5: DM-associated myositis-specific antibodies; send with the panel at diagnosis.
Anti-SRP: part of the myositis-specific antibody panel sent at workup.
Seronegative does not exclude: the panel is for phenotyping and risk-stratifying, biopsy remains the gold standard for diagnosis and classification.
🚨 Workup and Treatment, Step by Step
1
Confirm muscle injury: CK, usually > 10× normal, is the primary marker of muscle damage. Aldolase is also elevated and is more specific for muscle.
2
Localize it: EMG shows a myopathic pattern (short, small, polyphasic motor units with fibrillation potentials). MRI thighs on STIR shows edema in affected muscles and can guide the biopsy site so you do not sample uninvolved muscle.
3
Muscle biopsy: the gold standard for both diagnosis and classification, and the only way to catch the rimmed vacuoles of IBM before you commit someone to months of immunosuppression.
4
Start prednisone 1 mg/kg/day × 4–6 weeks, then taper over months once CK normalizes and strength improves. Taper by response, not by calendar.
5
Add a steroid-sparing agent: methotrexate or azathioprine, to get the patient off high-dose steroids. Add physical therapy to maintain function during and after treatment.
6
Screen in parallel: age-appropriate malignancy screening (especially in DM) and baseline PFTs for ILD. Do not wait until the myopathy is controlled to do these.
💊 Key Drugs
Prednisone (Deltasone)1 mg/kg/day, first-line; taper over months once CK normalizes and strength improves
Methotrexate (Trexall)15–25 mg weekly, steroid-sparing; give with folic acid; avoid in ILD (can cause drug-induced ILD)
Azathioprine (Imuran)2–3 mg/kg/day, steroid-sparing alternative; check TPMT first
IVIG2 g/kg over 2–5 days monthly, for refractory disease, especially DM
Rituximab (Rituxan)375 mg/m² × 4 weekly, for refractory myositis and antisynthetase-associated ILD
Mycophenolate (CellCept)refractory disease and antisynthetase ILD, where methotrexate is the wrong choice
📊 Monitoring
CK plus bedside strength together: CK alone can mislead. Rising CK means active myositis; a normal CK with worsening weakness means the steroids, not the disease, are the problem.
Serial PFTs q3–6 months if antisynthetase syndrome or any ILD, because ILD is the main driver of mortality and progresses quietly.
Baseline PFTs at diagnosis in every DM patient to have a comparison before dyspnea appears.
TPMT before azathioprine, and folic acid with methotrexate.
Repeat malignancy screening if anti-TIF1-γ positive; some guidelines recommend annually for 3–5 years because the cancer can surface after the myositis.
⚠️ Pitfalls
Calling steroid myopathy a flare. Both cause proximal weakness. Myositis flare: CK elevated/rising, inflammatory markers up. Steroid myopathy: CK normal, painless, no inflammatory markers. If CK is normal and weakness is worsening, reduce the steroid instead of escalating it.
Methotrexate in a patient with ILD: MTX can itself cause drug-induced ILD. Use mycophenolate, rituximab, or cyclophosphamide for antisynthetase ILD instead.
Missing IBM. Age > 50, asymmetric weakness, distal involvement (finger flexors, wrist flexors, "can't grip"), quadriceps atrophy ("can't walk"), CK only mildly elevated or normal, and no response to immunosuppression. Biopsy shows rimmed vacuoles plus amyloid. It is the most common inflammatory myopathy in the elderly.
Skipping cancer screening in adult DM because the muscles responded to steroids. The malignancy association is with the disease, not with treatment failure.
🏥 Malignancy Screening in DM
DM carries the strong association, PM a weaker one. Adult DM requires age-appropriate malignancy screening at diagnosis.
Where to look: ovarian, lung, breast, GI, lymphoma.
Anti-TIF1-γ positive means intensify: CT chest/abdomen/pelvis, mammogram, colonoscopy, pelvic exam.
Repeat, do not treat as a one-time box: some guidelines recommend annual screening for 3–5 years.
🎓 Escalate / Refer When
Anti-Jo-1 positive, or new dyspnea and dry cough: get PFTs and HRCT chest. In antisynthetase syndrome the ILD, not the myopathy, is what kills.
Refractory to prednisone plus a steroid-sparing agent: escalate to rituximab, IVIG, or mycophenolate.
Asymmetric distal weakness that failed a 6-month steroid trial: stop escalating immunosuppression and rebiopsy for rimmed vacuoles. IBM has no effective immunosuppressive treatment; the plan becomes PT/OT and fall prevention.
Dysphagia: formal swallowing evaluation. It is common in IBM, and IVIG may help swallowing even when it does nothing for strength.
Evidence-based tools to estimate prognosis and guide goals-of-care discussions. PPI, PPS, and surprise question for cancer. ePrognosis for geriatrics. Prognostication is imperfect -communicate uncertainty honestly.
🔍 Overview
Key Prognostic Tools
Tool
Population
What It Predicts
Surprise Question
Any serious illness
"Would I be surprised if this patient died in the next 12 months?" If no → initiate palliative discussion.
PPS (Palliative Performance Scale)
Cancer and non-cancer
Functional status 0–100%. PPS ≤ 50% → median survival ~6 months. PPS ≤ 30% → days to weeks.
PPI (Palliative Prognostic Index)
Cancer
Predicts survival < 3 weeks vs > 6 weeks based on PPS, oral intake, edema, dyspnea, delirium.
3-month mortality in cirrhosis. Transplant prioritization.
Seattle Heart Failure Model
Heart failure
1–5 year survival in chronic HF based on multiple variables.
Physicians systematically overestimate survival -by a factor of 3–5× on average. Use validated tools to supplement clinical judgment. Communicate in ranges, not precise dates.
Key Evidence: Physicians overestimate survival by 3-5x on average Christakis, 2000. The surprise question has ~70% sensitivity/specificity for 12-month mortality Downar, 2017. PPI accurately predicts survival < 3 weeks Morita, 1999. Feeding tubes do not improve survival in advanced dementia Teno, 2012. Functional trajectories differ by disease type and shape prognostic communication Lunney, 2003.
🚨 Management
Communicating Prognosis
Ask before telling: "How much information would you like to know about what to expect?"
Use ranges: "We're talking about days to weeks" or "weeks to months" rather than specific dates
Frame honestly: "I hope for the best, but I'm worried we may be looking at weeks rather than months"
Acknowledge uncertainty: "No one can predict exactly -these are estimates based on what we know"
Functional decline trajectory: Describe what to expect (increasing sleep, decreasing intake, less interaction)
Prognostication itself does not involve medications. When prognosis guides transition to comfort care, see the Code Status & Advance Directives topic for symptom management medications (morphine for pain/dyspnea, lorazepam for anxiety, glycopyrrolate for secretions, haloperidol for agitation).
📋 On Rounds
Pimp Questions
What is the "surprise question" and how accurate is it?
"Would I be surprised if this patient died in the next 12 months?" A negative answer (you would NOT be surprised) identifies patients who would benefit from palliative care discussions. Sensitivity ~70%, specificity ~70%. It performs best as a screening tool -not for precise prognostication, but for triggering earlier goals-of-care conversations. Can be applied to any illness.
Why do physicians consistently overestimate survival?
Multiple cognitive biases: (1) Optimism bias -physicians want patients to do well, (2) Therapeutic optimism -belief that treatment is helping more than it is, (3) Anchoring -to the patient's best functional state rather than current trajectory, (4) Patient expectations -pressure from patients/families who want hope. Studies show physicians overestimate by 3–5× on average. Using validated prognostic tools helps counteract these biases.
What is PPS and how do you score it?
Palliative Performance Scale: 0-100% in 10% increments. Based on 5 domains: ambulation, activity/evidence of disease, self-care, intake, and level of consciousness. PPS 50% = mainly sit/lie, unable to work, considerable assistance needed, reduced intake. PPS ≤ 30% correlates with days to weeks survival.
What are the components of the Palliative Prognostic Index (PPI)?
How do you use the "Karnofsky" vs "ECOG" performance status?
Karnofsky: 0-100 scale (100 = normal, 0 = dead). ECOG/Zubrod: 0-5 scale (0 = fully active, 5 = dead). ECOG is simpler and most used in clinical trials. KPS < 40 or ECOG ≥ 3 suggests limited treatment tolerance and poor short-term prognosis.
What is the trajectory of functional decline in cancer vs organ failure vs dementia?
Cancer: relatively preserved function, then rapid decline in last weeks/months. Organ failure (CHF, COPD): gradual decline with acute exacerbations, each potentially fatal, partial recovery between. Dementia/frailty: slow progressive decline over years. Lunney, 2003. Trajectory shapes communication approach.
What is the "PaP score" and when is it used?
Palliative Prognostic Score: uses dyspnea, anorexia, KPS, clinical prediction of survival, WBC count, and lymphocyte percentage. Divides into 3 risk groups: A (>70% chance of 30-day survival), B (30-70%), C (<30%). Pirovano, 1999. Useful for cancer patients when objective prognostication is needed.
What lab values suggest poor prognosis in advanced illness?
Albumin < 2.5, elevated LDH, leukocytosis, lymphopenia, elevated CRP/inflammatory markers, rising creatinine. Low albumin is the strongest single lab predictor across disease types. Note: albumin reflects inflammation (negative acute phase reactant), not nutritional status per ASPEN 2021.
How do you communicate prognosis when the family asks "How long does he have?"
Use ranges not specific dates: "days to weeks," "weeks to months." Frame with hope and honesty: "I hope for the best, but I'm worried we may be looking at weeks." Offer to explain what to expect functionally. Ask what they need to accomplish in that time. Never say "there's nothing more we can do" - always offer what you CAN do for comfort.
Clinical Examples
📋 Case 1 - Prognostication in Advanced Cancer
Scenario: 78M with metastatic colon cancer, no further chemo options. PPS 40% (mainly in bed, extensive disease, considerable assistance, normal-reduced intake, drowsy). Family asks: "How much time does he have?"
Assessment:
PPS 40% - median survival ~4-6 weeks
PPI: PPS 30-50 (2.5) + reduced intake (1) + no edema (0) + no dyspnea at rest (0) + no delirium (0) = 3.5 - predicts survival > 6 weeks
Clinical trajectory: declining over past 2 weeks, now bed-bound most of day
Lab markers: albumin 2.1, rising LDH - poor prognostic signs
Communication: "Based on what we're seeing, I'm worried we may be looking at weeks to a few months. I hope I'm wrong, but I want to make sure you have time to do the things that matter most to your family."
Teaching point: Use multiple tools (PPS + PPI + clinical trajectory + labs) rather than relying on any single predictor. Convergence of multiple indicators increases confidence.
📋 Case 2 - Prognostication in End-Stage Heart Failure
Scenario: 82F with NYHA Class IV HF, EF 15%, on home inotropes. Third hospitalization in 2 months. Not a transplant or LVAD candidate. Surprise question: "No, I would not be surprised if she died in the next 12 months."
Recurrent hospitalizations despite optimized GDMT - marker of end-stage trajectory
NYHA IV + inotrope dependence - median survival 6-12 months without advanced therapies
Functional trajectory: organ failure pattern with stepwise decline and incomplete recovery between exacerbations
Communication: "Her heart is getting weaker despite our best treatments. Each hospitalization is harder to recover from. I think we're looking at months rather than years. I want to make sure we're focusing on what matters most to her."
Teaching point: Heart failure prognostication is harder than cancer because of the unpredictable exacerbation pattern. Patients may die suddenly from arrhythmia even when "stable." Use the surprise question to trigger earlier GOC discussions.
📋 Case 3 - Prognostication in Advanced Dementia
Scenario: 89F with advanced Alzheimer's, FAST stage 7C (nonambulatory, minimal verbal, requires total care). Recurrent aspiration pneumonia. Nursing home asks about feeding tube placement.
Assessment:
FAST 7C - median survival ~12 months (range 6-24 months)
Recurrent aspiration pneumonia in advanced dementia - 6-month mortality ~50%
CASCADE study: feeding tubes do NOT prevent aspiration, do NOT improve survival, and increase agitation in advanced dementia
Functional trajectory: slow progressive decline typical of dementia/frailty trajectory
Communication: "Your mother's dementia has reached an advanced stage where her body is losing the ability to swallow safely. A feeding tube would not prevent aspiration and studies show it doesn't help people with advanced dementia live longer. I'd recommend we focus on careful hand feeding for comfort and pleasure, and discuss what your mother would have wanted."
Teaching point: The Choosing Wisely campaign and multiple studies recommend against feeding tubes in advanced dementia. This is one of the clearest evidence-based recommendations in palliative care. Frame as what you CAN do (hand feeding, comfort), not what you won't do.
⚡ Summary
Why Tools Beat Intuition
Physicians systematically overestimate survival, on average by a factor of 3 to 5. The error grows with a longer doctor-patient relationship, and it delays hospice referral, which is how patients spend their last months in hospital rather than at home. Use a validated tool to supplement judgment, not to replace it.
Start With the Surprise Question
'Would I be surprised if this patient died in the next 12 months?' A 'no' should trigger goals-of-care planning. Sensitivity and specificity are each around 70%, which is imperfect but far better than unaided estimation, and it takes seconds. It works across cancer and non-cancer illness.
Match the Tool to the Population
PPS scores function from 0 to 100% in both cancer and non-cancer disease; PPS 50% or below suggests a median survival of about 6 months. PPI is cancer-specific and separates a survival under 3 weeks from over 6 weeks using performance status, oral intake, edema, dyspnea at rest and delirium. ePrognosis for community-dwelling older adults. APACHE for ICU mortality.Using a cancer tool on a heart failure patient gives a number with no validity.
Know the Illness Trajectory You Are In
Cancer: high function preserved until a fairly sharp terminal decline over weeks to months, which is what makes prognosis most predictable here. Organ failure (heart failure, COPD): a saw-tooth of exacerbations with incomplete recovery, and death often occurs during an exacerbation that looked survivable.Dementia and frailty: a slow decline over years, where the prognostic markers are weight loss, recurrent infection and loss of ambulation rather than any single test.
Communicate in Ranges
'Hours to days', 'days to weeks', 'weeks to months', 'months to years'.Never give a precise date: it will be wrong, and families anchor on it and lose trust when it passes. Ranges convey the same planning information while being honest about the uncertainty.
Ask Permission and Check Understanding
'Would it be helpful to talk about what to expect with time?' Some patients want detail, some want the broad picture, and some want the family told instead. Ask before you tell, then check what they took away. Name the uncertainty explicitly rather than hiding it: saying you cannot be certain builds credibility rather than undermining it.
Hope and Prognosis Are Not in Conflict
Use 'hope for, prepare for' framing: hope the treatment works while preparing for the possibility it does not. Do not offer false reassurance and do not strip hope away; both damage the relationship at the moment it matters most. Respond to emotion before adding information, since nothing said after a shock is retained.
Let the Estimate Change Something
A prognosis is only useful if it drives a decision: hospice referral, advance directive completion, deprescribing preventive medications, stopping burdensome monitoring, or bringing a family conversation forward. Revisit it as the clinical picture changes, because a prognosis given at diagnosis is stale a month later, and document it so the next team is not starting from scratch.
RoundsRx Infographic Series · #117 · Oncology & Palliative · PDF 146 KB
Text version
PALLIATIVE CARE · One Pager
Prognostication Tools
Each tool is validated for one population and answers one question. Use tools to correct clinical judgment, which systematically runs optimistic, then communicate in ranges, never in dates.
🧪 Which Tool, Which Population
Surprise question (any serious illness): "Would I be surprised if this patient died in the next 12 months?" If no, start the palliative discussion. Sensitivity and specificity ~70%, so it is a screening trigger, not a prognosis.
PPS, Palliative Performance Scale (cancer and non-cancer): functional status 0–100% in 10% increments across ambulation, activity and evidence of disease, self-care, intake, and consciousness. PPS ≤ 50% predicts median survival ~6 months; PPS ≤ 30% means days to weeks.
PPI, Palliative Prognostic Index (cancer): combines PPS, oral intake, edema, dyspnea at rest, and delirium. PPI > 6 predicts survival < 3 weeks (sensitivity 83%, specificity 85%).
PaP, Palliative Prognostic Score (cancer): dyspnea, anorexia, KPS, clinical prediction of survival, WBC, lymphocyte %. Sorts into group A (> 70% chance of 30-day survival), B (30–70%), C (< 30%).
Weeks: bed-bound most of the day, minimal oral intake, drowsy, dependent for all ADLs.
Days: bed-bound, minimal consciousness, mottling, Cheyne-Stokes breathing, no oral intake.
Hours: unresponsive, irregular breathing, cool and mottled extremities, mandibular breathing.
These physical signs are what let you narrow the range you give the family, which is why the exam at the door matters more than any score in the last days.
🚨 Communicating Prognosis, Step by Step
1
Ask before telling: "How much information would you like to know about what to expect?" Not everyone wants numbers, and unwanted numbers close the conversation down.
2
Use ranges: "days to weeks," "weeks to months," never a specific date, because a date will be heard as a promise and remembered as one.
3
Frame honestly: "I hope for the best, but I'm worried we may be looking at weeks rather than months." Hope and honesty in the same sentence.
4
Acknowledge uncertainty: "No one can predict exactly, these are estimates based on what we know."
5
Describe the trajectory: increasing sleep, decreasing intake, less interaction. Telling families what dying looks like ahead of time prevents each change being read as a new crisis.
6
Never say "there's nothing more we can do": ask what they need to accomplish in the time available and offer what you can still do for comfort.
📈 Decline Trajectories
Cancer: preserved function, then rapid decline in the final weeks. Relatively predictable, so the onset of decline itself signals end-stage.
Organ failure (CHF, COPD, ESRD, cirrhosis): gradual decline with acute exacerbations and partial recovery. Unpredictable, because any exacerbation may be the fatal one, which is why the surprise question earns its place here.
Dementia and frailty: slow progressive decline over years. Very prolonged, so the terminal phase is hard to identify at all.
Sudden death (MI, PE, stroke, trauma, arrhythmia): full function to death, no prognostic window, which is the argument for advance care planning in everyone.
📊 What To Assess
Functional status: PPS, Karnofsky, or ECOG, the strongest single bedside predictor across diseases.
Nutrition: weight loss trajectory, BMI, intake history. Albumin reflects inflammation, not nutrition, per ASPEN 2021.
Hospitalization frequency: readmissions mark a declining trajectory even when each individual admission looks survivable.
Symptom burden: a rising symptom load suggests progression.
Labs: albumin < 2.5, elevated LDH, leukocytosis, lymphopenia, elevated CRP, rising creatinine. Low albumin is the strongest single lab predictor across disease types.
Patient and family understanding and what they want to know.
⚠️ Pitfalls
Trusting your own estimate: physicians overestimate survival by 3–5× on average, driven by optimism bias, therapeutic optimism, anchoring to the patient's best functional state instead of the current trajectory, and pressure from families who want hope.
Applying a tool outside its population: PPI and PaP are validated in cancer, MELD in liver disease, Seattle in heart failure, APACHE in the ICU. A score's threshold does not transfer to another score's decision.
Relying on one predictor: converge PPS plus PPI plus clinical trajectory plus labs; agreement between them is what raises confidence.
Treating the surprise question as a prognosis: it screens for who needs the conversation, it does not estimate survival.
Reading albumin as a nutrition marker and then treating the number instead of the disease.
Feeding tubes in advanced dementia: they do not prevent aspiration, do not improve survival, and increase agitation. Offer careful hand feeding for comfort and pleasure instead.
🏥 Trigger The Goals Conversation When
You would not be surprised if the patient died within 12 months.
PPS ≤ 50% (median ~6 months) and certainly at PPS ≤ 30% (days to weeks), because at that point the window for planning is closing.
PPI > 6 in a cancer patient, predicting survival < 3 weeks.
Recurrent hospitalizations despite optimized therapy in organ failure, since each exacerbation may be fatal and a stable-looking patient can die suddenly from arrhythmia.
Advanced dementia with recurrent aspiration, when the question of a feeding tube is being raised.
Family asks "how long?" Answer with a range, not a refusal.
🎓 Key Evidence
Christakis, 2000 physicians overestimate survival by 3–5× on average.
Downar, 2017 surprise question performance for 12-month mortality, good enough to screen, not to prognosticate.
Morita, 1999 PPI > 6 predicts survival < 3 weeks in cancer.
Pirovano, 1999 PaP score validation, three 30-day survival groups.
Lunney, 2003 four end-of-life trajectories, which is why prognostic communication differs by disease.
Teno, 2012 feeding tubes do not improve survival in advanced dementia.
Related Topics
Code Status & Advance DirectivesFamily Meeting FrameworkGoals of Care & Symptom ManagementHospice Eligibility CriteriaNon-Opioid Symptom ManagementOpioid Rotation Conversion
High-YieldNephro
Contrast-Induced Nephropathy
AKI within 48–72h of iodinated contrast exposure. Rise in Cr ≥ 0.3 mg/dL or ≥ 50% from baseline. Risk factors: CKD, diabetes, dehydration, high contrast volume. Prevention: IV NS hydration before and after contrast.
🔍 Overview
Definition & Risk Factors
Contrast-induced nephropathy (CIN) or contrast-associated AKI: rise in serum creatinine ≥ 0.3 mg/dL or ≥ 50% from baseline within 48–72 hours of iodinated contrast administration.
Risk Factor
Details
CKD (eGFR < 30)
#1 risk factor. Risk is very low with eGFR > 45.
Diabetes + CKD
Combined = highest risk. Diabetes alone (without CKD) is NOT a significant risk factor.
Volume depletion
Dehydration concentrates contrast in kidneys → direct tubular toxicity
High contrast volume
Risk proportional to volume. Minimize contrast used.
Nephrotoxic medications
NSAIDs, aminoglycosides, ACEi/ARBs (hold if possible day of contrast)
Heart failure
Reduced renal perfusion
Risk of CIN has been overestimated. Recent large studies suggest true contrast-induced AKI is much less common than previously thought, especially with IV contrast (vs intra-arterial). Do NOT withhold indicated CT scans for fear of CIN -delayed diagnosis is often more dangerous.
Pathophysiology
Direct tubular toxicity, osmotic injury to renal tubular epithelial cells from hyperosmolar contrast
Renal vasoconstriction → medullary ischemia, outer medulla is a vulnerable watershed zone with baseline low oxygen tension; contrast exacerbates ischemia
Reactive oxygen species (ROS), contrast generates free radicals → oxidative injury to tubular cells
Important caveat: Recent evidence suggests much of what was historically attributed to "CIN" was actually coincidental AKI in sick hospitalized patients. True causes in many cases: cholesterol emboli (especially after cardiac cath), hemodynamic changes, sepsis, nephrotoxic medications. The term "contrast-associated AKI" (CA-AKI) is preferred over "CIN" to reflect this uncertainty.
IV vs Intra-arterial Contrast
Route
Risk
Notes
IV contrast (CT scans)
Very low risk of true CIN, even in CKD
Multiple large propensity-matched studies show minimal additional AKI risk beyond what would occur without contrast. Do NOT withhold indicated CT scans.
Contrast delivered directly to renal arteries at high concentration. This is where most true CIN occurs. Volume of contrast is the key modifiable risk factor.
Updated Practice: The risk of IV contrast-induced AKI has been significantly overestimated. AMACING, 2017 showed that in patients with eGFR 30–59, prophylactic IV hydration provided NO benefit over no prevention. PRESERVE, 2018 showed bicarb is not superior to NS, and NAC is not beneficial. Current radiology guidelines state: do not withhold indicated contrast CT scans in patients with AKI or CKD. Delayed diagnosis from avoiding imaging is often more harmful than the small risk of CIN.
🚨 Management
Prevention Protocol
IV isotonic saline -1 mL/kg/hr for 6–12h before AND 6–12h after contrast. #1 proven prevention.
Hold nephrotoxins -NSAIDs, aminoglycosides. Consider holding ACEi/ARB day of contrast.
Metformin:Updated (ACR 2022): If eGFR ≥ 45, no need to hold. If eGFR 30–44, hold day of contrast, resume 48h later if Cr stable. eGFR < 30, hold regardless. Risk is lactic acidosis if contrast causes AKI → metformin accumulates. Old blanket "hold metformin for all contrast" is outdated.
Use low-osmolar or iso-osmolar contrast
N-acetylcysteine -no longer recommended (multiple trials show no benefit)
Avoid repeat contrast within 48–72h if possible
KDIGO-based CIN Prevention Protocol
eGFR
Risk Level
Pre-Procedure Protocol
eGFR > 45
Low risk
Routine hydration. No special precautions needed.
eGFR 30–45
Moderate risk
IV NS 1 mL/kg/hr × 6–12h before contrast
eGFR < 30
High risk
IV NS 1 mL/kg/hr × 6–12h before AND after contrast. Minimize contrast volume. Consider alternative imaging if appropriate.
Emergency Situations
Do NOT delay emergent imaging for hydration. In life-threatening situations (PE, aortic dissection, stroke, trauma), proceed with contrast CT immediately.
If time allows: Give a bolus of NS 3 mL/kg over 1h before contrast, then continue hydration post-procedure.
CIN, if it occurs, is usually self-limited. A missed diagnosis is not.
Hold Nephrotoxins
NSAIDs, hold before and after contrast
Aminoglycosides, hold if possible
ACEi/ARB, consider holding day of procedure (controversial but reasonable in high-risk patients)
🧪 Workup
Baseline creatinine + eGFR -assess risk
BMP at 48–72h post-contrast -check for Cr rise
Urinalysis -muddy brown granular casts (ATN pattern)
Urine sodium -may be elevated (tubular injury)
Assess volume status -dehydration increases risk
💊 Medications
Intervention
Details
Evidence
IV NS
1 mL/kg/hr × 6–12h pre- and post-contrast
Best evidence for prevention. Only proven intervention.
IV NaHCO₃
3 mL/kg/hr × 1h pre, then 1 mL/kg/hr × 6h post
PRESERVE, 2018 showed NOT superior to NS. Use NS instead.
N-Acetylcysteine (Mucomyst)
600–1200 mg PO BID × 2 days
No longer recommended.ACT, 2011 and PRESERVE, 2018 showed no benefit.
Hold metformin
Hold 48h AFTER contrast
Prevents lactic acidosis if AKI develops. Resume when Cr stable.
📋 On Rounds
Pimp Questions
Should you hold a contrast CT in a patient with CKD and acute illness?
Generally no -do not withhold indicated imaging. The risk of CIN has been overestimated in observational studies (confounded by other causes of AKI in sick patients). Multiple recent studies suggest true IV contrast-induced AKI is uncommon. Delayed or missed diagnosis from avoiding CT is often more dangerous than the small risk of CIN. Hydrate, minimize contrast volume, and proceed with the study if clinically indicated.
Why was N-acetylcysteine (NAC) removed from CIN prevention protocols?
NAC was widely used for decades based on small, conflicting studies. ACT, 2011 and PRESERVE, 2018 definitively showed that NAC provides no benefit over IV saline alone for preventing CIN. Furthermore, NAC may cause a spurious decrease in creatinine (analytically interferes with the assay), giving a false impression of renal protection. Current guidelines recommend IV hydration only.
📋 Case 1, CKD Patient Needing Contrast CT
Patient: 72M with CKD stage 3b (eGFR 38), diabetes. Needs CT abdomen/pelvis for suspected diverticular abscess. Team wants to avoid contrast.
Recommendation: Proceed with contrast CT.
eGFR 38 = low-moderate risk for CIN
IV NS 1 mL/kg/hr × 6h before and after contrast
Hold metformin 48h after contrast
Missing an abscess that needs drainage is worse than CIN risk
Key lesson: Do not withhold indicated contrast imaging in CKD patients. Hydrate appropriately and proceed.
📋 Case 2, Post-Cardiac Cath AKI
Patient: 55F post-cardiac catheterization (200 mL contrast), eGFR 25, diabetes. Cr was 2.1 pre-cath, now 2.8 at 48h. UOP decreasing.
Diagnosis: Contrast-associated AKI (intra-arterial route, high risk).
Management:
Aggressive IV hydration (monitor for volume overload)
Hold all nephrotoxins
Monitor Cr daily
Most cases self-resolve in 7–14 days
Dialysis rarely needed
Key lesson: Intra-arterial contrast (cardiac cath) carries higher CIN risk than IV contrast. High contrast volume + low baseline eGFR = highest risk combination.
📋 Case 3, Emergent CT-PE with Elevated Creatinine
Patient: 40F in ED with acute dyspnea, tachycardia, pleuritic chest pain. Wells score 6 (PE likely). eGFR unknown but Cr was 1.8 last year.
Intern asks: Should we wait for today's Cr before ordering CT-PE?
Answer: NO. Emergent CT-PE now.
A missed PE can be fatal
CIN risk is low with IV contrast
Give concurrent NS bolus while patient is in CT
Do NOT delay life-saving imaging for CIN prevention
Key lesson: In emergent situations, the risk of a missed diagnosis always outweighs the risk of CIN. Proceed with imaging and hydrate concurrently.
⚡ Summary
The Risk Has Been Substantially Overestimated
Much of what was historically called contrast nephropathy was coincidental acute kidney injury in sick hospitalized patients.Do not withhold an indicated CT for fear of contrast: a missed pulmonary embolism, dissection or abscess causes far more harm than the contrast will. After cardiac catheterization, cholesterol embolization is often the real culprit, and it behaves quite differently.
Define It Properly
A rise in creatinine of 0.3 mg/dL or more, or 50% or more above baseline, within 48 to 72 h of iodinated contrast, with other causes excluded.The exclusion clause is the whole diagnosis: hypotension, sepsis, nephrotoxins and volume depletion in the same 48 hours are far commoner explanations.
Know Who Is Actually at Risk
eGFR below 30 is the main risk factor, and the risk is very low above 45.Diabetes matters only in combination with chronic kidney disease; diabetes alone is not a significant risk factor. Add volume depletion, high contrast volume, heart failure and concurrent nephrotoxins.
IV and Intra-Arterial Are Not the Same Exposure
Intra-arterial contrast with first-pass renal exposure, as in coronary or renal angiography, carries appreciably more risk than an intravenous CT.Most of the historical evidence came from cardiac catheterization and was then applied to CT, which is a large part of why the CT risk was overstated.
Hydration Is the Only Prevention That Works
Isotonic saline before and after the contrast, typically 1 to 3 mL/kg/h for several hours either side.AMACING found no benefit from prophylactic hydration in patients with eGFR 30 to 59, so reserve it for genuinely high-risk patients rather than giving it reflexively.
Two Things That Do Not Work
N-acetylcysteine and sodium bicarbonate both failed in PRESERVE, which showed no benefit over saline for either. Stop ordering them. Prophylactic hemodialysis after contrast also does not prevent injury and adds procedural risk.
Minimize the Dose and the Cotoxins
Use the smallest contrast volume that answers the question, prefer iso-osmolar or low-osmolar agents, and avoid repeat studies within 48 to 72 h.Hold NSAIDs, aminoglycosides and other nephrotoxins around the study, and hold metformin at the time of contrast in significant renal impairment, restarting 48 h later once the creatinine is confirmed stable, because of the lactic acidosis risk if kidney function drops.
In an Emergency, Just Scan
A genuinely emergent indication overrides the renal concern.Give fluids concurrently if you can, but do not delay the study, since the diagnoses these scans rule out kill faster than any contrast effect. Dialysis patients with no residual function can receive contrast freely, and there is no need to rush them to an urgent session afterward.
RoundsRx Licensed Content - Unauthorized Use Prohibited
CommonID
Diabetic Foot Infection
Polymicrobial infection in neuropathic/ischemic diabetic foot. Probe-to-bone test (PPV ~89% for osteomyelitis). Mild: oral antibiotics. Moderate-severe: IV antibiotics + surgery. Vascular assessment critical -ischemia = poor healing.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Epidemiology
15–25% of diabetics develop a foot ulcer in their lifetime; ~50% of those ulcers become infected
Diabetic foot infections (DFI) are the leading cause of non-traumatic lower-extremity amputation
Annual incidence: ~6% in patients with neuropathy; 5-year mortality after major amputation approaches 50%
Most infections are polymicrobial -gram-positives (Staph, Strep) dominate mild cases; gram-negatives and anaerobes join in moderate-severe
Pathophysiology
Neuropathy → deformity → ulceration → infection. Peripheral neuropathy (sensory, motor, autonomic) removes protective sensation. Motor neuropathy causes intrinsic muscle wasting and foot deformity (claw toes, prominent metatarsal heads). Autonomic neuropathy reduces sweating → dry, cracked skin. Combined with peripheral arterial disease (PAD), the result is tissue breakdown with impaired healing and immune response. Hyperglycemia further impairs neutrophil function and wound healing.
The Triad of Diabetic Foot Failure: Neuropathy (can't feel injury) + PAD (can't heal injury) + Hyperglycemia (can't fight infection). All three must be addressed for treatment success.
IDSA/IWGDF Classification
IDSA Grade
Severity
Clinical Features
Setting
1
Uninfected
Wound without purulence or signs of inflammation
Wound care only, offloading
2
Mild
Erythema < 2 cm from wound edge, superficial (skin/subcutaneous only), no systemic signs
Outpatient oral antibiotics
3
Moderate
Erythema > 2 cm, deep tissue involvement (abscess, fascia, muscle, bone, joint), no SIRS
Inpatient IV antibiotics ± surgery
4
Severe
Any foot infection with SIRS/sepsis, limb-threatening ischemia, or necrotizing features
ICU, emergent surgery, broad-spectrum IV
IDSA DFI Guidelines, 2012 -classification drives antibiotic selection, setting of care, and need for surgical intervention.
Wagner Classification
Grade
Description
0
Intact skin, bony deformity (at-risk foot)
1
Superficial ulcer
2
Deep ulcer to tendon, capsule, or bone (no abscess/osteo)
3
Deep ulcer with abscess, osteomyelitis, or joint sepsis
4
Localized gangrene (forefoot or heel)
5
Extensive gangrene (entire foot)
Limb-Threatening vs Non-Limb-Threatening
Limb-threatening features (any one = urgent): deep space abscess, extensive cellulitis (> 2 cm), crepitus/gas gangrene, necrotizing fasciitis, critical limb ischemia (ABI < 0.4), wet gangrene, SIRS/sepsis. These require emergent surgical evaluation and broad-spectrum IV antibiotics.
Non-limb-threatening: Superficial infection, erythema < 2 cm, no deep tissue involvement, intact vasculature, no systemic signs → outpatient management with close follow-up
When to Suspect Osteomyelitis
Probe-to-bone test positive -sterile blunt probe contacts bone through ulcer → positive LR ~6 for osteomyelitis (PPV ~89% in high-prevalence population)
Ulcer > 2 cm in diameter or > 3 mm deep
ESR > 70 mm/hr (specificity ~90% for osteomyelitis in DFI setting)
Visible bone or palpable bone at wound base
"Sausage toe" (diffuse swelling of a single digit)
Non-healing ulcer despite 6 weeks of appropriate wound care and offloading
Rule of thumb: If you can see or feel bone, assume osteomyelitis until proven otherwise. A positive probe-to-bone test in a high-risk patient has a PPV approaching 89% -order MRI to confirm.
Pseudomonas risk: Water exposure, failed prior therapy, warm/tropical climate
🧪 Workup
Bedside Assessment
Probe-to-bone test -do on EVERY diabetic foot wound. Insert sterile blunt metal probe into wound. If you touch hard, gritty surface → positive (PPV ~89%). Simple, bedside, takes 10 seconds.
Measure erythema -mark borders with skin marker, measure from wound edge. < 2 cm = mild, > 2 cm = moderate.
Assess depth -superficial (skin/subcut only) vs deep (fascia, muscle, tendon, bone, joint)
Pedal pulses -dorsalis pedis and posterior tibial. Absent/diminished → order ABI
Monofilament test -10g monofilament to assess neuropathy at plantar sites
Laboratory Workup
Routine (all patients)
CBC -leukocytosis (may be absent in immunocompromised diabetics)
BMP -renal function (impacts antibiotic dosing), glucose
CRP -sensitive but nonspecific; useful for trending treatment response
ESR -> 70 mm/hr has ~90% specificity for osteomyelitis in DFI
HbA1c -chronic glycemic control (target < 7% for wound healing)
Wound culture -deep tissue biopsy or curettage >>> surface swab. Surface swabs grow colonizers, not pathogens. Obtain AFTER debridement of necrotic tissue.
If moderate-severe or systemic signs
Blood cultures × 2 -draw before starting antibiotics. Positive in ~15% of moderate-severe DFI.
Procalcitonin -helps distinguish systemic infection from localized; useful for monitoring treatment response
Lactate -if concern for sepsis
Coags -if surgical intervention planned
NEVER base antibiotic therapy on surface swab cultures. Every chronic wound is colonized -swabs grow colonizers (often multidrug-resistant), leading to inappropriately broad antibiotics. Always obtain deep tissue culture during debridement or curettage of the ulcer base.
Osteomyelitis changes take 10-14 days to appear; sensitivity only ~55%
MRI
Gold standard for osteomyelitis
Bone marrow edema, rim enhancement, soft tissue extent
Sensitivity ~90%, specificity ~80%. Charcot arthropathy can mimic osteo.
WBC-labeled scan
When MRI contraindicated
Focal uptake in bone = osteomyelitis
Lower resolution; paired with sulfur colloid scan for specificity
Vascular Assessment
ABI (ankle-brachial index) -first-line. ABI < 0.9 = PAD. ABI < 0.5 = critical limb ischemia. Caution: ABI may be falsely elevated (> 1.3) in diabetics due to medial artery calcification.
TBI (toe-brachial index) -more reliable in diabetics (toe arteries less prone to calcification). TBI < 0.7 = PAD, TBI < 0.4 = unlikely to heal without revascularization.
Arterial duplex ultrasound -anatomic localization of stenosis/occlusion if revascularization considered
CTA/MRA -pre-surgical planning for revascularization
No wound will heal without adequate blood supply. If ABI < 0.5 or TBI < 0.4, consult vascular surgery for revascularization BEFORE expecting wound healing from antibiotics and wound care alone.
Consults
Podiatry -wound care, debridement, offloading strategies, custom orthotics
Vascular surgery -if ABI/TBI abnormal or absent pedal pulses → revascularization evaluation
Orthopedics/Plastics -if deep tissue debridement needed, bone resection for osteomyelitis, or soft tissue reconstruction
Amputation may be limb- or life-saving in extensive gangrene or necrotizing infection
Duration: 2-4 weeks (adjust based on surgical margins and response)
Osteomyelitis Management
Medical (antibiotics alone): 6 weeks total duration. Consider if no surgical indication (stable bone, no abscess, no dead bone).
Surgical resection + antibiotics: If bone is resected with clean margins, duration can be shortened to 2-4 weeks post-resectionIDSA DFI Guidelines, 2012
Bone biopsy -gold standard for diagnosis AND culture-guided therapy. Surface swab does NOT correlate with bone pathogens.
IV-to-oral switch -acceptable once clinically stable with identified organism and susceptibility-guided oral agent with good bone penetration (fluoroquinolones, TMP-SMX, linezolid, doxycycline) OVIVA, 2019
OVIVA Trial (2019): Oral antibiotics were non-inferior to IV for bone and joint infections at 1 year (treatment failure 14.6% oral vs 14.1% IV). This supports early IV-to-oral switch when an appropriate oral agent is available.
Wound Care Principles
Debridement -sharp debridement of all necrotic, callous, and nonviable tissue. Repeat as needed.
Offloading -total contact cast (TCC) is gold standard for plantar ulcers. Alternatives: removable cast walkers, therapeutic shoes. Non-weight-bearing if possible.
Moist wound healing -appropriate dressings (foam, alginate, hydrogel) to maintain moisture without maceration
Glycemic control -target glucose < 180 mg/dL during acute infection. Long-term HbA1c < 7% for optimal healing.
Nutrition -correct protein-calorie malnutrition. Consider wound healing supplements (zinc, vitamin C). Note: albumin/prealbumin reflect inflammation, not nutritional status (ASPEN, 2021).
Vascular Intervention
Revascularization if ABI < 0.5 or TBI < 0.4 -wound will not heal without adequate perfusion
Options: angioplasty/stenting (endovascular) or bypass grafting (surgical)
Timing: revascularize early -do not wait for antibiotic course to fail before addressing ischemia
Multidisciplinary approach: vascular surgery + ID + podiatry = best outcomes
💊 Medications
Empiric Antibiotic Selection
Severity
Empiric Regimen
Organisms Covered
Duration
Key Notes
Mild
Amoxicillin-Clavulanate (Augmentin) 875/125 PO BID
Workhorse for moderate DFI. Add vanco if MRSA risk.
Moderate (Pseudomonas risk)
Piperacillin-Tazobactam (Zosyn) 3.375g IV q6h ± Vancomycin (Vancocin)
Broad including Pseudomonas, MRSA
2–3 weeks
Water exposure, failed prior therapy, tropical climate
Severe
Vancomycin (Vancocin) + Piperacillin-Tazobactam (Zosyn) 4.5g IV q6h
MRSA, Pseudomonas, GNR, anaerobes
2–4 weeks
Escalate to meropenem if MDR risk
Severe (MDR risk)
Vancomycin (Vancocin) + Meropenem (Merrem) 1g IV q8h
MRSA, ESBL, Pseudomonas, anaerobes
2–4 weeks
Reserve for MDR, prior broad abx exposure, nosocomial
Osteomyelitis
Guided by bone culture
Culture-directed
6 weeks (or 2–4 wks post-resection)
IV-to-oral switch acceptable OVIVA, 2019
MRSA-Specific Agents
Drug
Dose
Route
Key Notes
Vancomycin (Vancocin)
15–20 mg/kg IV q8–12h (target AUC/MIC 400-600)
IV
First-line IV MRSA agent. Monitor troughs or AUC. Nephrotoxic.
Daptomycin (Cubicin)
6–8 mg/kg IV daily
IV
Alternative to vancomycin. Check weekly CPK. Inactivated by surfactant -do not use for pneumonia.
Linezolid (Zyvox)
600 mg PO/IV q12h
PO/IV
100% oral bioavailability. Good bone penetration. Limit to 2 weeks if possible (serotonin syndrome, myelosuppression, lactic acidosis with prolonged use).
TMP-SMX (Bactrim)
DS 1-2 tabs PO BID
PO
Good MRSA coverage. Add cephalexin for Strep gap. Good bone penetration.
Doxycycline
100 mg PO BID
PO
Alternative oral MRSA option. Good soft tissue penetration.
OPAT-Friendly Options
Ertapenem (Invanz) 1g IV daily -once-daily, covers gram-pos + gram-neg + anaerobes. NO Pseudomonas coverage. Excellent for moderate DFI OPAT. SIDESTEP, 2005
Daptomycin (Cubicin) 6 mg/kg IV daily -once-daily MRSA option for OPAT
Ceftriaxone (Rocephin) 2g IV daily + Metronidazole (Flagyl) 500 mg PO TID -alternative once-daily IV backbone
SIDESTEP Trial (2005): Ertapenem was non-inferior to piperacillin-tazobactam for diabetic foot infections, with the advantage of once-daily dosing -making it ideal for outpatient parenteral therapy (OPAT).
Duration Summary
Infection Type
Duration
Notes
Mild soft tissue
1–2 weeks
Outpatient oral. Reassess at 48–72h.
Moderate soft tissue
2–3 weeks
IV → oral step-down when improving
Severe soft tissue
2–4 weeks
Based on response, source control adequacy
Osteomyelitis (no surgery)
6 weeks
Culture-guided. IV-to-oral switch acceptable.
Osteomyelitis (post-resection, clean margins)
2–4 weeks
Shortened if bone resected with no residual infected bone
Post-amputation (clean margins)
2–5 days
Prophylactic only if margins clear. Longer if margins positive.
📋 On Rounds
Pimp Questions
Why should you get deep tissue cultures instead of surface swabs in diabetic foot infections?
Surface swabs grow colonizing organisms (every chronic wound is colonized), NOT the true pathogens causing deep infection. Deep tissue cultures from debridement or curettage provide accurate pathogen ID and sensitivities. Surface swabs lead to inappropriately broad antibiotics and treatment failures. Never base antibiotic selection on surface swab cultures.
What is the significance of ESR > 70 in a diabetic foot wound?
ESR > 70 mm/hr has ~90% specificity for osteomyelitis in the DFI setting. Combined with a positive probe-to-bone test, the probability of osteo approaches 95%. While not diagnostic alone, it significantly raises pre-test probability and supports MRI imaging. ESR is also useful for monitoring treatment response during antibiotic therapy.
A patient has a diabetic foot ulcer with a positive probe-to-bone test but normal X-ray. What do you do next?
Order an MRI -gold standard for osteomyelitis (sensitivity ~90%). Plain film changes take 10-14 days to appear and have sensitivity of only ~55%. A positive probe-to-bone test (LR ~6) already raises probability significantly. MRI shows bone marrow edema and rim enhancement before cortical destruction is visible on X-ray. Do not wait for X-ray changes to treat osteomyelitis.
When can you switch from IV to oral antibiotics for diabetic foot osteomyelitis?
The OVIVA trial (2019) showed oral antibiotics are non-inferior to IV for bone/joint infections. Switch when: (1) clinically improving, (2) adequate source control (debridement done), (3) organism identified with susceptibilities, (4) a highly bioavailable oral agent with good bone penetration is available (fluoroquinolones, TMP-SMX, linezolid). No need for 6 weeks of IV.
Why is vascular assessment critical before starting wound care in a diabetic foot?
No wound heals without adequate blood supply. If ABI < 0.5 or TBI < 0.4, the foot has critical limb ischemia -antibiotics and wound care alone will fail. Revascularization must be pursued before expecting healing. Note: ABI may be falsely elevated (> 1.3) in diabetics due to medial artery calcification -TBI is more reliable. The triad for DFI success = antibiotics + surgery + vascular perfusion.
What is the role of total contact casting in diabetic foot ulcers?
Total contact cast (TCC) is the gold standard for offloading plantar ulcers. It redistributes pressure across the entire foot, reducing focal pressure at the ulcer site by 60-80%. TCC achieves healing rates of ~90% within 12 weeks vs ~30% with standard footwear. Compliance is built in -the patient cannot remove it. Contraindications: active deep infection, significant PAD, excessive drainage.
Clinical Examples
📋 Case 1, Moderate DFI with Osteomyelitis
Patient: 62M with T2DM (A1c 9.8%), presents with left foot ulcer between 4th and 5th toes, purulent drainage, erythema extending 3 cm from wound edge, no fever, WBC 11.2.
Surgical consult: debridement + deep bone biopsy for culture (NOT surface swab)
Vascular surgery consult: ABI 0.6 → may need revascularization for wound healing
6 weeks antibiotics for osteomyelitis, guided by bone culture. IV-to-oral switch acceptable OVIVA, 2019
Glucose control: target < 180 during acute infection
Teaching point: The triad for DFI success = antibiotics + surgical debridement + vascular assessment. Missing any one → treatment failure.
📋 Case 2, Severe DFI with Sepsis
Patient: 71F with T2DM, CKD3, presents with foul-smelling left foot wound, crepitus on palpation, T 39.4°C, HR 118, BP 88/52, WBC 24k, lactate 4.1.
Key findings: Wet gangrene of 1st and 2nd toes with gas on palpation. Absent pedal pulses bilaterally. SIRS/sepsis criteria met → IDSA grade 4 (severe).
Vancomycin (Vancocin) + Meropenem (Merrem) 1g IV q8h (broad coverage including MRSA, Pseudomonas, anaerobes)
Emergent surgical consult: debridement vs partial amputation. Do NOT delay surgery for imaging.
X-ray confirms gas in soft tissue → surgical emergency.
Vascular assessment post-stabilization: CTA to evaluate for revascularization potential.
Teaching point: Gas gangrene / necrotizing infection in a diabetic foot is a surgical emergency. Antibiotics are adjunctive -the scalpel is the definitive treatment. Amputation may be life-saving.
📋 Case 3, Mild DFI Managed Outpatient
Patient: 55M with well-controlled T2DM (A1c 6.9%), presents with plantar ulcer under 2nd metatarsal head, mild surrounding erythema (1.5 cm from wound edge), no purulence, no systemic signs. Pedal pulses 2+ bilaterally.
Assessment: IDSA grade 2 (mild). Probe-to-bone negative. ABI 1.0 (normal vasculature). X-ray: no bony changes.
Management:
Amoxicillin-Clavulanate (Augmentin) 875/125 PO BID × 2 weeks
Sharp debridement of wound edges, moist dressing changes daily
Offloading: removable cast walker, strictly non-weight-bearing to affected foot
Follow-up in 48-72 hours: mark erythema borders to track progression
Diabetes education: daily foot checks, proper footwear, glucose control
Teaching point: Not every DFI needs hospitalization. Mild infections with intact vasculature, no deep tissue involvement, and no systemic signs can be safely managed outpatient with close follow-up. The key is reliable follow-up at 48-72h to confirm response.
Sample Presentation
One-Liner
"Mr. Garcia is a 62-year-old with uncontrolled T2DM who presented with a left foot ulcer with 3 cm surrounding erythema, positive probe-to-bone test, and MRI-confirmed osteomyelitis of the 5th metatarsal, consistent with moderate diabetic foot infection with osteomyelitis."
Key Points to Cover on Rounds
IDSA severity: moderate (grade 3) with osteomyelitis. Antibiotics: Unasyn day 3, bone biopsy culture growing MSSA -narrowing to nafcillin, planning IV-to-oral switch to TMP-SMX per OVIVA data. Wound: post-debridement, granulation tissue forming, no residual necrosis. Vascular: ABI 0.6, vascular surgery recommends angioplasty for SFA stenosis -scheduled for tomorrow. Glucose: on insulin drip, target < 180, transitioning to basal-bolus today. ESR trending 82 → 64. Plan: 6-week antibiotic course from bone biopsy date, oral step-down after revascularization, podiatry for TCC when wound ready.
Daily Rounds Checklist
Wound assessment → Erythema improving or expanding? Mark borders daily. Any new drainage, crepitus, or necrosis?
Cultures finalized? → Narrow antibiotics when sensitivities return. What day of antibiotics are we on?
Osteomyelitis addressed? → Bone biopsy done? MRI obtained? Surgical plan for resection vs medical management?
Vascular status → ABI/TBI ordered? Vascular surgery consult? Revascularization plan?
Glucose control → Target < 180 mg/dL. On insulin drip vs basal-bolus? HbA1c obtained?
Offloading in place? → Non-weight-bearing? TCC or removable cast walker ordered?
Inflammatory markers → ESR/CRP trending down? If plateauing, reassess source control and antibiotic adequacy.
Nutrition → Adequate protein intake for wound healing? Note: albumin/prealbumin reflect inflammation, NOT nutritional status (ASPEN, 2021). Assess nutrition by intake history, weight trend, and physical exam.
IV-to-oral switch? → Clinically improving + adequate source control + oral agent with good bone penetration available? OVIVA, 2019
Discharge planning → OPAT if continued IV needed? Podiatry follow-up? Wound care plan? Diabetes education?
Monitoring Parameters
Parameter
Frequency
Target / Action
Wound assessment
Daily
Mark erythema borders, measure wound size, assess drainage
Temperature
q4–8h
Defervescence expected within 48–72h of appropriate therapy
WBC / CRP
q48–72h
Trending down = responding. Plateau = reassess source control.
ESR
Weekly (osteo)
Slow decline expected. Useful for monitoring 6-week course.
A sterile blunt probe reaching bone through the ulcer has a positive predictive value of about 89% for osteomyelitis.It is free, takes seconds, and outperforms most imaging as a first step, so it is done at the bedside before ordering an MRI.
Grade the Severity, Because It Sets the Route
Mild: local infection with erythema under 2 cm, treated with oral antibiotics.Moderate: deeper or more extensive infection, IV antibiotics.Severe: systemic toxicity, IV antibiotics plus urgent surgical debridement.Limb-threatening features are extensive necrosis, gangrene, deep abscess and critical ischemia.
Assess the Circulation in Every Patient
Ischemia is what determines whether the foot heals, no matter how correct the antibiotic.Check pulses, ankle-brachial index (unreliable in calcified vessels, so add toe pressures or transcutaneous oxygen) and refer to vascular surgery early.Antibiotics cannot reach tissue with no blood supply.
Cover Polymicrobially, Then Narrow
These are polymicrobial infections: gram-positives, gram-negatives and anaerobes.Add MRSA cover for severe infection, known colonization or high local prevalence, and Pseudomonas cover for macerated wounds, water exposure or prior treatment failure.Culture deep tissue at debridement, not the surface swab, which grows colonizers and misdirects therapy.
Surgery Is Part of the Treatment
Debride necrotic tissue, drain abscesses and relieve pressure.Antibiotics without debridement fail in anything beyond a mild infection, because devitalized tissue and biofilm are not penetrated. Involve podiatry or surgery early rather than after a failed course.
Offload the Wound
A total contact cast or equivalent offloading device is what allows a neuropathic ulcer to heal.A patient who keeps walking on the ulcer will not heal it whatever else is done, and this is the intervention most often omitted because it is inconvenient. Wound care principles: debride, keep moist, control exudate, and reassess weekly.
Duration Depends on Bone
Soft tissue infection: 1 to 2 weeks for mild, 2 to 3 weeks for moderate to severe.Osteomyelitis: about 6 weeks if the bone is retained, but only 2 to 5 days if all infected bone is resected, because after complete resection you are treating a soft tissue wound. Getting this distinction right avoids weeks of unnecessary IV therapy.
Prevent the Next Ulcer
Annual foot examination with monofilament testing, daily self-inspection, properly fitted footwear, and podiatric nail and callus care.Amputation risk after a first ulcer is high and recurrence is the rule, so the prevention plan is as important as the treatment. Optimize glycemic control and address smoking, which compounds the ischemia.
Multimodal non-opioid strategies for pain, nausea, dyspnea, constipation, insomnia, pruritus, and hiccups in hospitalized patients. Layer therapies by mechanism. Assess with validated tools. Anticipate symptoms before they escalate. Comfort is always achievable without defaulting to opioids.
🔎 Overview
Why Non-Opioid First?
Opioids carry risks of respiratory depression, delirium, constipation, dependence, and falls, especially in elderly and hospitalized patients. A multimodal non-opioid approach targets multiple pain and symptom pathways, reduces opioid requirements by 30–50%, and improves functional recovery.
Multimodal analgesia, combine agents with different mechanisms (peripheral, central, anti-inflammatory) to achieve synergistic relief at lower individual doses
Anticipatory prescribing, order PRN symptom medications on admission before symptoms escalate
Non-pharmacologic adjuncts, positioning, fan therapy, sleep hygiene, music therapy, ice/heat, and spiritual care are evidence-based and underutilized
Goals-of-care alignment, symptom management intensity should match patient and family goals
Stimulant laxative (senna) + osmotic (PEG) is the evidence-based regimen. Docusate is no better than placeboAGA-ACG, 2023, do not use. Start bowel regimen with every opioid order.
Insomnia
Sleep hygiene protocol, Melatonin 3–5mg QHS
Trazodone (Desyrel) 25–50mg QHS
Avoid benzodiazepines and zolpidem in hospitalized patients, delirium, falls, respiratory depression risk. Fix the environment first.
Baclofen (Lioresal) 5–10mg TID, Gabapentin (Neurontin) 100–300mg TID
Metoclopramide (Reglan) 10mg TID (if gastric stasis), Chlorpromazine (Thorazine) 25–50mg
Chlorpromazine is the only FDA-approved drug but is held in reserve (sedation, hypotension, QTc, EPS). Baclofen/gabapentin are first-line for tolerability. Persistent > 48h or intractable > 1 month needs a cause workup.
Non-Pharmacologic Interventions
Non-pharmacologic therapies are evidence-based, low-risk, and should be offered to every hospitalized patient alongside medications. They are not "alternative" medicine, they are standard of care.
Pain: ice/heat application, positioning, physical therapy, TENS unit, guided imagery, music therapy
4 features: acute onset + fluctuating course, inattention, disorganized thinking, altered consciousness. Need features 1+2 plus 3 or 4.
Pre-Prescribing Checklist
Before prescribing any symptom medication, always check renal function, hepatic function, and perform medication reconciliation. Many common non-opioid agents require dose adjustment or are contraindicated in organ dysfunction.
Renal function (eGFR): NSAIDs contraindicated if eGFR < 30. Gabapentin requires dose reduction. PEG 3350 safe in CKD. Avoid magnesium-based laxatives in renal failure.
Hepatic function: Acetaminophen max 2g/day in cirrhosis (not contraindicated, just dose-reduce). Avoid NSAIDs in cirrhosis (GI bleed + hepatorenal syndrome risk). Ondansetron max 8mg/day in severe hepatic impairment.
Medication reconciliation: Identify drug-induced symptoms, PPIs cause hypomagnesemia, statins cause myalgias, antibiotics cause nausea/diarrhea, diuretics cause constipation. Treat the cause, not just the symptom.
Polypharmacy screening: Anticholinergic burden score, hydroxyzine + diphenhydramine + promethazine stacked = delirium risk. Use Beers Criteria in elderly.
Step 1 (Mild, NRS 1–3): Scheduled Acetaminophen 1g PO q6h + non-pharm (ice, heat, positioning). Step 2 (Moderate, NRS 4–6): Add NSAID (Ibuprofen 400mg q6h or Ketorolac 15–30mg IV q6h x 5 days max) + adjuvant (Gabapentin for neuropathic, Cyclobenzaprine for muscle spasm, Lidocaine 5% patch for localized). Step 3 (Severe, NRS 7–10): All of above + consult pain service. Low-dose opioid may be needed as rescue only, not as default.
Scheduled acetaminophen,1g PO/IV q6h (max 4g/day; 2g/day in hepatic impairment). Reduces opioid consumption by ~30%. Schedule it, PRN acetaminophen is rarely requested by patients. Sinatra, 2005
NSAIDs, excellent for inflammatory, musculoskeletal, and renal colic pain. Ketorolac (Toradol) 15–30mg IV q6h (max 5 days, GI/renal toxicity). Ibuprofen 400–600mg PO q6h with food. Avoid in CKD (eGFR < 30), GI bleed history, heart failure, cirrhosis PRECISION, 2016
Gabapentinoids, first-line for neuropathic pain. Gabapentin 100–300mg TID (titrate up). Pregabalin 75mg BID. Reduce dose in renal impairment. Side effects: sedation, dizziness, peripheral edema.
Lidocaine 5% patch, apply to area of maximal pain (not on broken skin). Up to 3 patches simultaneously, 12h on / 12h off. Excellent for post-herpetic neuralgia, localized musculoskeletal pain.
Muscle relaxants,Cyclobenzaprine (Flexeril) 5–10mg TID for acute musculoskeletal spasm. Avoid in elderly (anticholinergic, sedation). Short-term only (2–3 weeks).
Ketamine (sub-anesthetic),0.1–0.3 mg/kg/hr IV infusion for refractory pain. Pain service consult. Evidence in sickle cell crisis, burns, opioid-tolerant patients.
Dexamethasone 4–8mg IV daily (reduces edema + direct antiemetic)
Anticipatory / Anxiety
Pre-chemo, anxiety-related
Lorazepam (Ativan) 0.5–1mg, behavioral therapy
Metoclopramide warning: avoid in complete bowel obstruction (risk of perforation). Limit duration to < 12 weeks, risk of tardive dyskinesia with prolonged use (FDA black box). Promethazine (Phenergan): causes significant sedation and tissue necrosis if given IV (give deep IM only). Avoid in elderly, strong anticholinergic.
Dyspnea, Non-Opioid Strategies
Fan therapy, direct airflow to face. Stimulates trigeminal V2 mechanoreceptors, suppresses central breathlessness perception. Multiple RCTs demonstrate efficacy. Free, safe, first-line for all causes of dyspnea.
Positioning, upright or tripod position improves diaphragm mechanics and reduces venous return (reduces pulmonary congestion)
Supplemental O2, only if SpO2 < 90%. In non-hypoxic dyspnea, supplemental O2 is no better than room air via fan Abernethy, 2010
Anxiolytics,Lorazepam (Ativan) 0.5mg SL/PO for anxiety-driven dyspnea component. Use cautiously, sedation risk
Low-dose opioids (exception), morphine 2mg IV q2h treats air hunger centrally by reducing ventilatory drive to hypoxia/hypercapnia. This is the one scenario where low-dose opioids are appropriate even in a non-opioid strategy.
Treat the cause, diuresis for CHF, thoracentesis for large effusion, antibiotics for pneumonia, bronchodilators for COPD/asthma
Constipation, Stepwise Approach
Step 1:PEG 3350 (MiraLAX) 17g PO daily (osmotic, first-line) + Senna (Senokot) 2 tabs PO BID (stimulant). Start with every opioid order. Do NOT use docusate (Colace), no better than placebo per AGA-ACG, 2023.
Step 2: Add PEG 3350 (MiraLAX) 17g in 8oz water daily (osmotic). Safe in renal failure. Takes 1–3 days for effect.
Step 3:Bisacodyl (Dulcolax) 10mg PO or PR for acute relief. Suppository works within 15–60 min.
Step 4 (opioid-induced):Methylnaltrexone (Relistor) 8–12mg SC q48h. Peripheral mu-opioid antagonist, reverses GI opioid effects WITHOUT reversing analgesia. Also: Naloxegol (Movantik) 25mg PO daily.
Avoid: magnesium-based laxatives in CKD (hypermagnesemia risk), lactulose if concern for bowel obstruction
Rule out obstruction first: If no BM for > 3 days with nausea/vomiting/distension, get a KUB or CT abdomen before aggressive laxative therapy. Stimulant laxatives in mechanical obstruction can cause perforation.
Insomnia, Hospital Sleep Protocol
Sleep hygiene first, minimize nighttime vitals/labs (cluster care), earplugs + eye mask, reduce ambient light, limit caffeine after noon, consistent wake time, turn off unnecessary alarms and monitors
First-line:Melatonin 3–5mg PO QHS (30 min before desired sleep). Safe, minimal interactions, no delirium risk. Evidence supports use in ICU to restore circadian rhythm.
Second-line:Trazodone (Desyrel) 25–50mg PO QHS. Serotonin antagonist/reuptake inhibitor. Causes drowsiness without anticholinergic burden. Low delirium risk vs alternatives.
Avoid in hospitalized patients: benzodiazepines (delirium, falls, respiratory depression), zolpidem/Ambien (parasomnias, falls, delirium, Beers Criteria), diphenhydramine for sleep (anticholinergic, delirium, especially in elderly)
Pruritus, Cause-Directed Therapy
Etiology
Treatment
Notes
Histamine-mediated (allergic, drug reaction, urticaria)
Hydroxyzine (Vistaril) 25mg PO q6h or Diphenhydramine (Benadryl) 25mg PO/IV q6h
Hydroxyzine preferred, less anticholinergic than diphenhydramine. Avoid diphenhydramine in elderly (Beers Criteria).
Cholestyramine (Questran) 4g PO BID–TID, Rifampin 150mg PO BID, Naltrexone 25–50mg PO daily
Cholestyramine binds bile salts. Separate from other meds by 2h (reduces absorption). Rifampin induces bile salt metabolism.
Uremic (CKD/ESRD)
Gabapentin (Neurontin) 100mg PO after each dialysis session, UVB phototherapy
Gabapentin is first-line for uremic pruritus, dose-adjust for renal function. Antihistamines less effective here.
Opioid-induced
Rotate opioid, Nalbuphine 2.5–5mg IV, Ondansetron 4mg IV
Mu-receptor mediated. Ondansetron can help. Nalbuphine (mixed agonist-antagonist) reverses pruritus without reversing analgesia.
Hiccups (Singultus), Persistent & Intractable
Definitions drive the workup:acute < 48h (benign, self-limited, no workup), persistent > 48h, intractable > 1 month. Persistent and intractable hiccups are a symptom of underlying pathology until proven otherwise, not a benign reflex, so look for a cause before just suppressing them. The hiccup reflex arc runs afferent (phrenic, vagus, sympathetic T6–T12) → central (medulla/brainstem) → efferent (phrenic → diaphragm), so irritation anywhere along that path can trigger it, which is why the differential is so broad.
Find the cause (most common first)
GI (most common): GERD, gastric distension, hiatal hernia, PUD, pancreatitis, hepatitis, subphrenic abscess. Why it matters: often reversible with a PPI, decompression, or simethicone.
Drugs (common and missed):dexamethasone / corticosteroids (classic in onc and palliative patients), benzodiazepines, opioids, chemotherapy, alpha-methyldopa. Review the med list first, stopping or switching the offender often fixes it without adding a drug.
CNS: stroke (classically lateral medullary / Wallenberg), brainstem lesion, MS, tumor, encephalitis. Suspect if any focal neuro signs, get brain imaging.
Phrenic / vagus irritation along its course: neck mass or goiter, mediastinal mass, pneumonia, empyema, pericarditis, MI, esophagitis, aortic aneurysm.
Metabolic: uremia, hyponatremia, hypocalcemia, hypokalemia. Cheap to check and reversible.
Post-operative, psychogenic, idiopathic (diagnosis of exclusion).
Workup for persistent / intractable
Med review + BMP, LFTs, glucose first (catches the drug cause and the metabolic causes for almost no effort).
CXR for diaphragm, mediastinum, lungs.
Escalate only if red flags: CT chest/abdomen, brain MRI if any neuro sign, EGD if GI symptoms, ECG. Do not order everything at once, let the history target the imaging.
Treatment ladder
Treat the cause + non-pharmacologic first: PPI for GERD, simethicone or NG decompression for gastric distension, stop the offending drug. Vagal / nasopharyngeal maneuvers (breath-hold/Valsalva, swallowing granulated sugar, cold-water gargle, catheter tip in the posterior pharynx).
First-line drug: Baclofen (Lioresal) 5–10 mg PO TID (up to q6h). GABA-B agonist with the best trial evidence; preferred first-line in chronic/palliative patients because it lacks the long-term movement-disorder risk of neuroleptics. Why caution in renal impairment: baclofen is renally cleared and accumulates, causing sedation and encephalopathy, dose-reduce in CKD.
First-line alternative: Gabapentin (Neurontin) 100–300 mg PO TID, titrate to effect (max ~1200 mg/day). Well tolerated; especially useful when hiccups coexist with neuropathic pain or in cancer patients.
If gastric stasis/distension: Metoclopramide (Reglan) 10 mg PO TID. Prokinetic; the other agent with RCT support (65% vs 24% placebo improvement). Why time-limit it: tardive dyskinesia risk rises with duration, keep courses short.
Reserve: Chlorpromazine (Thorazine) 25–50 mg PO TID–QID or 25 mg IV. The only FDA-approved drug for hiccups, but now held in reserve rather than first-line because sedation, orthostatic hypotension, QTc prolongation, and extrapyramidal/tardive effects make it a poor long-term choice, especially in the elderly.
Refractory: haloperidol or valproate as alternatives; phrenic nerve block (IR-guided) as a last resort when drugs fail and hiccups are disabling.
IV vs PO Considerations
Use PO whenever possible, equivalent efficacy for most agents, lower cost, fewer line-related complications
IV preferred when: NPO status, active vomiting, severe acute pain requiring rapid onset, bowel obstruction/ileus, unreliable GI absorption (post-surgical, critical illness)
IV acetaminophen, onset 5–10 min (vs 30–60 min PO). Cost is ~100x higher. Reserve for NPO patients or immediate post-operative period. Switch to PO as soon as tolerating.
IV ketorolac, onset 10 min. Max 5 days (GI and renal toxicity). Convert to PO ibuprofen as soon as tolerating oral.
De-Escalation Strategies
Pain improving: Scheduled → PRN → discontinue. Remove ketorolac by day 5. Taper gabapentin (do not stop abruptly, seizure risk). Remove lidocaine patches last (benign).
Nausea resolved: Switch ondansetron from scheduled to PRN → discontinue after 24h symptom-free. Taper dexamethasone (do not stop abruptly if > 7 days).
At discharge: Reconcile all symptom medications. Provide written de-escalation plan. Avoid discharging patients on ketorolac, IV medications, or hospital-only agents.
💊 Medications
Non-Opioid Drug Reference
Drug
Class
Dose
Route
Max Daily
Key Considerations
Acetaminophen (Tylenol)
Analgesic/Antipyretic
1g q6h
PO/IV
4g (2g if hepatic impairment)
Schedule it, PRN is underused. Safe in CKD. IV onset 5 min but ~100x cost of PO.
Ibuprofen (Advil/Motrin)
NSAID
400–600mg q6h
PO
2400mg
Take with food. Avoid if eGFR < 30, GI bleed hx, CHF, cirrhosis. PRECISION, 2016
Ketorolac (Toradol)
NSAID (parenteral)
15–30mg q6h
IV/IM
120mg (day 1), 60mg (day 2+)
Max 5 days. Same contraindications as all NSAIDs. Excellent for renal colic, post-surgical, MSK pain.
Gabapentin (Neurontin)
Gabapentinoid
100–300mg TID
PO
3600mg (titrate slowly)
First-line neuropathic pain. Dose-adjust in renal impairment. Sedation, dizziness. Also treats uremic pruritus and hiccups.
Pregabalin (Lyrica)
Gabapentinoid
75mg BID
PO
600mg
~6× more potent than gabapentin (300 mg gabapentin ≈ 50 mg pregabalin). More predictable (linear) absorption. Schedule V controlled substance. Dose-adjust in CKD.
Lidocaine 5% patch (Lidoderm)
Topical anesthetic
1–3 patches to painful area
Topical
3 patches/12h (12h on/12h off)
No systemic absorption at standard doses. Safe in CKD/hepatic disease. Do not apply to broken skin.
Cyclobenzaprine (Flexeril)
Muscle relaxant
5–10mg TID
PO
30mg
Short-term use only (2–3 weeks). Avoid in elderly (anticholinergic, sedation). Contraindicated with MAOIs.
Ondansetron (Zofran)
5-HT3 antagonist
4mg q6h
IV/PO/ODT
16mg (8mg if hepatic impairment)
First-line antiemetic. Causes constipation, add senna. QTc prolongation at higher doses. ODT tab dissolves on tongue.
Metoclopramide (Reglan)
Dopamine antagonist / Prokinetic
10mg q6h
IV/PO
40mg
Prokinetic for gastroparesis. Avoid in complete bowel obstruction. Black box: tardive dyskinesia with > 12 weeks use.
Prochlorperazine (Compazine)
Dopamine antagonist / Phenothiazine
10mg q6h
IV/PO/PR
40mg
Excellent for migraine-associated nausea. Akathisia and EPS possible. Give with diphenhydramine 25mg to prevent dystonia.
Promethazine (Phenergan)
Phenothiazine / Antihistamine
12.5–25mg q4–6h
IM/PO/PR
75mg
Strongly anticholinergic, avoid in elderly. Never give IV push (tissue necrosis, gangrene). Give deep IM only.
Scopolamine (Transderm Scop)
Anticholinergic
1.5mg patch q72h
Transdermal
1 patch
Best for vestibular/motion-related nausea. Apply behind ear. Onset 4–8h. Crosses BBB, delirium risk in elderly.
Senna (Senokot)
Stimulant laxative
2 tabs (17.2mg) BID
PO
4 tabs (34.4mg)
Essential component of bowel regimen. Stimulates colonic motility. Takes 6–12h for effect.
Docusate (Colace) NOT RECOMMENDED
Stool softener
,
PO
,
No better than placebo per AGA-ACG, 2023. Removed from hospital formularies (UAB 2024). No FDA-approved indication. Do not prescribe. Use PEG 3350 + senna instead.
PEG 3350 (MiraLAX)
Osmotic laxative
17g in 8oz water daily
PO
34g
Safe in CKD. Tasteless, mixes into any liquid. Takes 1–3 days. Can increase to BID for refractory constipation.
Lactulose (Kristalose)
Osmotic laxative
15–30 mL daily–BID
PO
60 mL/day
Alternative to PEG. Also used for hepatic encephalopathy (30–45 mL q1–2h titrated to 3–4 BMs/day). More bloating than PEG. Safe in CKD.
Bisacodyl (Dulcolax)
Stimulant laxative
10mg PO or PR
PO/PR
30mg
Suppository works within 15–60 min (useful for acute relief). PO takes 6–12h. Do not crush enteric-coated tablets.
Melatonin
Hormone / Sleep aid
3–5mg QHS
PO
10mg
Safe, no delirium risk. Give 30 min before desired sleep. Evidence in ICU circadian rhythm restoration.
NSAIDs + ACEi/ARB + diuretic,"triple whammy" for AKI. Avoid this combination entirely.
Oral Herpes (HSV-1), Treatment & Pain Management
Oral HSV-1 is extremely common (seroprevalence ~50–80% of adults). Most inpatient encounters involve reactivation (herpes labialis / cold sores) or primary herpetic gingivostomatitis in immunocompromised patients. The key inpatient concern is oral pain preventing hydration and PO intake.
Scenario
Drug
Dose
Duration
Notes
Herpes Labialis (Cold Sores), Recurrent
First-line (episodic)
Valacyclovir (Valtrex)
2g PO BID × 1 day (2 doses, 12h apart)
1 day
Start at earliest prodrome (tingling, burning). Most convenient regimen. Adjust for CrCl < 50.
Alternative (episodic)
Acyclovir (Zovirax)
400 mg PO 5×/day × 5 days
5 days
Less convenient dosing. Cheaper. Adequate hydration to prevent crystalluria.
Alternative (episodic)
Famciclovir (Famvir)
1500 mg PO × 1 dose
1 dose
Single-dose option. Prodrug of penciclovir.
Suppressive therapy
Valacyclovir
500 mg–1g PO daily
Ongoing
For frequent recurrences (≥6/year). Reduces outbreaks by 70–80%. CDC STI Guidelines, 2021
Primary Herpetic Gingivostomatitis
Immunocompetent
Valacyclovir
1g PO BID × 7–10 days
7–10 days
Start within 72h of symptom onset. Acyclovir 400 mg PO 5×/day is alternative. Primary episode is more severe and prolonged.
Immunocompromised (mild–moderate)
Valacyclovir
1g PO BID × 7–14 days
7–14 days
Longer course. Step up to IV if not improving or unable to take PO. NIH OI Guidelines
Immunocompromised (severe) or NPO
Acyclovir IV
5 mg/kg IV q8h
7–14 days
For severe mucocutaneous HSV, disseminated disease, or patients unable to take PO. Transition to PO when lesions regressing. Hydrate aggressively, crystalluria/AKI risk.
Orolabial HSV in Immunocompromised (HIV, Transplant, Chemo)
Treatment
Valacyclovir
1g PO BID × 5–10 days
5–10 days
Or acyclovir 400 mg PO 5×/day. Famciclovir 500 mg PO BID is alternative.
Chronic suppression
Valacyclovir
500 mg PO BID
Ongoing
For CD4 < 200 or frequent recurrences. Acyclovir 400 mg PO BID is alternative.
Lidocaine Viscous 2%, When & How to Use
Lidocaine viscous is for oral mucosal pain relief, NOT a treatment for HSV. Use it as an adjunct for pain control when oral lesions prevent eating/drinking. The #1 goal in oral HSV management is maintaining hydration and PO intake.
Drug
Dose
How to Use
Max
Key Safety Points
Lidocaine Viscous 2%
15 mL (1 tbsp) swish & spit
Swish in mouth for 1–2 min, then spit out. Do not swallow unless pharyngeal pain (then gargle & swallow).
8 doses/24h. Minimum 3h between doses. Max 300 mg (4.5 mg/kg)
⚠️ Aspiration risk, numbs throat/swallow reflex. NPO × 60 min after use. ⚠️ Seizures/cardiac toxicity if absorbed excessively (traumatized mucosa). ⚠️ FDA Black Box in children < 3 yo (deaths reported). ⚠️ Methemoglobinemia risk.
Compounded, no standardized formula. Minimal evidence vs individual components. Commonly ordered but not superior to single-agent lidocaine viscous in most studies.
When to Use Lidocaine Viscous
Herpetic gingivostomatitis, severe oral pain preventing PO intake. Apply 15–30 min before meals to facilitate eating.
Chemotherapy-induced mucositis, common with 5-FU, methotrexate, melphalan (post-ASCT). WHO grade 3–4 mucositis.
Aphthous ulcers (canker sores), for symptomatic relief of large/multiple ulcers.
Esophageal candidiasis pain, as bridge while awaiting fluconazole effect (2–3 days).
Radiation mucositis, head/neck radiation patients with severe oral pain.
Do NOT use lidocaine viscous for: teething pain in infants/toddlers (FDA Black Box, deaths reported from accidental overdose). Do not apply to large areas of traumatized mucosa, rapid systemic absorption → seizures, cardiac arrest. Always NPO × 60 min after use to prevent aspiration.
📋 On Rounds
Pimp Questions
Why is a fan to the face effective for dyspnea, and when is it superior to supplemental oxygen?
Cool air flow across the trigeminal nerve (V2 distribution) stimulates mechanoreceptors that suppress the central perception of breathlessness. Multiple RCTs show it reduces dyspnea independent of SpO2. In non-hypoxic patients, supplemental O2 is no better than room air, a bedside fan is more effective, free, and has no side effects Abernethy, 2010.
Why should acetaminophen be scheduled rather than PRN in hospitalized patients?
Scheduled acetaminophen maintains steady-state plasma levels, providing consistent baseline analgesia. Studies show it reduces opioid consumption by ~30% compared to PRN dosing. Patients rarely request PRN acetaminophen because the pain must first worsen before they ask, defeating the purpose of multimodal analgesia. Max 4g/day (2g in hepatic impairment). Safe in CKD. Cost-effective and the foundation of the non-opioid pain ladder Sinatra, 2005.
Why should you NOT use docusate (Colace) for constipation, and what is the evidence-based bowel regimen?
Docusate is no better than placebo. The AGA-ACG 2023 guideline omitted docusate from all recommendations. McRorie 2021 reviewed 7 RCTs, none showed benefit over placebo. The Tarumi hospice RCT showed senna + docusate = senna + placebo. Docusate has no FDA-approved indication and has been removed from hospital formularies (UAB 2024). The evidence-based regimen is senna 2 tabs BID (stimulant) + PEG 3350 17g daily (osmotic). For opioid-induced constipation, add methylnaltrexone or naloxegol.
What is the maximum duration for ketorolac (Toradol) and why?
Maximum 5 days for any route (IV, IM, or PO). Beyond 5 days, the risk of GI bleeding increases 5-fold and risk of AKI rises significantly. Ketorolac inhibits COX-1 (protective gastric prostaglandins) and COX-2 (renal afferent vasodilation). It also inhibits platelet aggregation. Same contraindications as all NSAIDs: avoid in CKD, GI bleed history, CHF, cirrhosis, and patients on anticoagulants. Convert to PO ibuprofen as soon as patient tolerates oral.
Why should you avoid benzodiazepines and zolpidem for insomnia in hospitalized patients?
Both cause delirium, falls, and respiratory depression, the top 3 causes of hospital-acquired harm. Zolpidem (Ambien) causes parasomnias (sleep-walking, sleep-eating) and is on the Beers Criteria for inappropriate use in elderly. Benzodiazepines impair consolidation of memory and worsen sleep architecture long-term. First-line is melatonin 3–5mg QHS (no delirium risk) followed by trazodone 25–50mg (low anticholinergic burden). Fix the hospital environment first: earplugs, eye mask, cluster nighttime care.
How do you manage cholestatic pruritus differently from histamine-mediated pruritus?
Cholestatic pruritus is caused by bile salt deposition in skin, not histamine release, so antihistamines are largely ineffective. First-line: cholestyramine (Questran) 4g BID–TID, a bile acid sequestrant (separate from other meds by 2h). Second-line: rifampin 150mg BID (induces bile salt metabolism, monitor LFTs). Third-line: naltrexone 25–50mg daily (endogenous opioid tone contributes to cholestatic itch). Histamine-mediated pruritus responds to H1 blockers (hydroxyzine, diphenhydramine).
Clinical Examples
📋 Case 1, Multimodal Pain Management Post-Hip Fracture
Patient: 82 y/o F with osteoporosis and CKD3 (eGFR 38), admitted with left hip fracture awaiting surgical repair. NRS pain score 7/10 at rest, 9/10 with movement.
Scheduled Acetaminophen 1g PO q6h (safe in CKD, max 4g/day)
Gabapentin 100mg PO BID (dose-reduced for CKD, titrate to 100mg TID)
Lidocaine 5% patch to anterior thigh/hip region (12h on/12h off)
Ice packs to hip q2h for 20 min, positioning with pillows between knees
Fascia iliaca nerve block by anesthesia (single-shot or continuous catheter, gold standard for hip fracture)
Reserve low-dose morphine 2mg IV q4h PRN for breakthrough only
Teaching point: In elderly patients with CKD, the non-opioid toolbox becomes critical because both NSAIDs and opioids carry high risk. Regional anesthesia (nerve block) + scheduled acetaminophen + gabapentin + topical agents can achieve excellent pain control with minimal systemic side effects.
📋 Case 2, Refractory Nausea in Bowel Obstruction
Patient: 65 y/o M with metastatic colon cancer, admitted with partial small bowel obstruction. Persistent nausea/vomiting despite ondansetron 4mg IV q6h. NG tube in place.
Key considerations: Ondansetron targets 5-HT3 pathway. Bowel obstruction nausea is multifactorial, need mechanism-based approach. Metoclopramide contraindicated in complete obstruction.
Management:
Continue Ondansetron 4mg IV q6h (partial benefit)
Add Dexamethasone 8mg IV daily (reduces bowel wall edema + direct antiemetic via central mechanisms)
Add Haloperidol 0.5mg IV q8h (dopamine antagonist, different pathway than ondansetron)
Scopolamine patch 1.5mg behind ear (anticholinergic, reduces GI secretions and vestibular input)
Avoid metoclopramide (prokinetic in obstruction = perforation risk)
Surgical and palliative care co-management for goals of care
Teaching point: When first-line antiemetic fails, layer agents from different receptor classes rather than increasing the dose. Ondansetron (5-HT3) + haloperidol (D2) + scopolamine (muscarinic) + dexamethasone (central) provides quadruple-pathway coverage.
📋 Case 3, Hospital-Acquired Insomnia and Delirium Prevention
Patient: 75 y/o M, POD 2 after colectomy. Reports sleeping < 2 hours per night since admission. CAM negative but appearing increasingly confused during daytime. Night nurse requesting "something for sleep."
Key considerations: Post-surgical elderly patient at extreme delirium risk. Sleep deprivation is a major delirium trigger. Benzodiazepines and zolpidem will precipitate delirium.
Management:
Environmental: Cluster nighttime vitals/labs, earplugs + eye mask, lights off by 10 PM, curtains open by 7 AM, minimize nighttime alarms
Melatonin 5mg PO QHS (restore circadian rhythm, no delirium risk)
Trazodone 25mg PO QHS if melatonin insufficient (low anticholinergic burden)
Review medication list, discontinue any unnecessary anticholinergics, steroids at bedtime
Do NOT order zolpidem, lorazepam, or diphenhydramine for sleep
Teaching point: Sleep deprivation is a modifiable delirium risk factor. The hospital environment is inherently sleep-disruptive. Fix the environment first, then use melatonin (safe) or trazodone (safe), never benzodiazepines or zolpidem in post-surgical elderly patients.
Sample Presentation
One-Liner
"Mrs. Chen is an 82-year-old with CKD3 and osteoporosis admitted with a left hip fracture, currently managed with a multimodal non-opioid regimen including scheduled acetaminophen, gabapentin, lidocaine patch, and a fascia iliaca block, with pain scores improved from 9 to 3 at rest."
Key Points to Cover on Rounds
Pain: NRS 3/10 at rest (down from 9), 5/10 with PT (down from 9). Regimen: acetaminophen 1g q6h scheduled, gabapentin 100mg TID, lidocaine 5% patch x1, fascia iliaca catheter running. No opioids used in 24h. Bowels: PEG 3350 + senna ordered prophylactically, last BM yesterday. Sleep: melatonin 5mg QHS, slept 5 hours (improved from 2). Delirium screen: CAM negative. Plan: continue multimodal regimen, PT eval today, surgery tomorrow AM, pre-op anesthesia nerve block plan confirmed.
Daily Rounds Checklist
Pain score today? → NRS at rest AND with activity. Trend from yesterday? Is multimodal regimen working?
Acetaminophen scheduled? → If not, why not? This should be on every patient unless contraindicated (active liver failure).
NSAID appropriate? → Check eGFR, GI bleed history, anticoagulation status, CHF. If on ketorolac, what day are we on? (Max 5)
Bowel regimen ordered? → PEG 3350 + senna (not docusate, ineffective per AGA-ACG 2023). If on opioids, is it adequate? Last BM? Abdominal exam?
Nausea controlled? → Is antiemetic matched to mechanism? If ondansetron failing, try different receptor pathway.
Sleep last night? → Hours slept. Is environment optimized? Melatonin ordered? Avoid benzos/zolpidem in elderly.
Renal/hepatic function today? → Dose-adjust gabapentin for CKD. Reduce acetaminophen for hepatic impairment. Remove NSAIDs if AKI develops.
De-escalation plan? → Are symptoms improving? Can we step down from IV to PO? From scheduled to PRN? Discharge-ready regimen?
⚡ Summary
Layer by Mechanism, Not by Potency
Comfort is almost always achievable without defaulting to opioids.Identify the mechanism generating the symptom and treat that pathway, then add a second agent working at a different site rather than escalating the first. Anticipate symptoms and schedule treatment before they escalate, since breakthrough symptoms are harder to control than prevented ones.
Rule Out the Reversible Cause First
Urinary retention, constipation, infection, hypercalcemia, hypoxia, medication effect and undertreated anxiety masquerade as almost every symptom on this page.A confused, agitated or breathless patient with a full bladder or an impacted rectum needs that fixed, not a drug added, and this is the single highest-yield step before prescribing anything.
Pain: Build the Non-Opioid Base
Scheduled acetaminophen and, where safe, an NSAID form the base of the modified WHO ladder, and they are opioid-sparing at every level above it. Add a mechanism-specific adjuvant: gabapentinoid or a tricyclic for neuropathic pain, a muscle relaxant for spasm, a bisphosphonate or radiation for bone metastases, and topical lidocaine or capsaicin for localized pain.
Nausea: Pick the Drug by the Pathway
Chemotherapy or radiation, a 5-HT3 pathway: ondansetron.Gastroparesis or early satiety, a prokinetic problem: metoclopramide.Opioid, metabolic or uremic, a dopaminergic chemoreceptor trigger zone problem: haloperidol or prochlorperazine.Vestibular or motion-related: an antihistamine or scopolamine.Giving ondansetron for every nausea is why so much of it fails.
Dyspnea: A Fan Beats Oxygen in the Normoxic
Airflow across the face stimulates the trigeminal nerve and reduces breathlessness, and it works when oxygen does not. Oxygen helps only if the patient is hypoxemic. Add positioning, pacing, breathing techniques, treatment of the reversible cause, and a low-dose opioid where non-opioid measures are insufficient.
Constipation: Prevent It, and Do Not Use Fiber Reflexively
Start a stimulant laxative with the first opioid dose, because tolerance to opioid-induced constipation never develops. Stimulant plus osmotic, escalating to suppositories and enemas.Avoid bulk-forming fiber in immobile or poorly hydrated patients, where it worsens impaction. Exclude obstruction before treating, and consider a peripheral opioid antagonist for refractory opioid-induced constipation.
Insomnia: Fix the Ward Before Reaching for a Drug
Cluster nocturnal observations, dim lights, reduce noise, avoid overnight bloods and weights, and maintain daytime light and activity.Avoid benzodiazepines and Z-drugs, which cause delirium and falls, particularly in the elderly. Melatonin, trazodone or a sedating antihistamine are options only after the environment has been addressed and the cause, pain, dyspnea, nocturia or anxiety, has been treated.
Match the Route and De-Escalate
Use the oral route while it works; switch to sublingual, subcutaneous or rectal when swallowing fails, and reserve IV for when nothing else is available.For pruritus, treat the cause, cholestyramine or rifampin for cholestasis, gabapentin for uremic itch, since antihistamines fail in both. For persistent hiccups, chlorpromazine, baclofen or metoclopramide, after excluding a phrenic or diaphragmatic irritant.Review and stop what is no longer needed, since accumulated symptom drugs become their own source of delirium and falls.
Hiccups: baclofen 5–10mg TID or gabapentin 100–300mg TID first-line; chlorpromazine 25–50mg (only FDA-approved, reserve)
⚠️ High-Risk Pitfalls
Ketorolac > 5 days → GI bleed + AKI
NSAIDs + ACEi + diuretic = "triple whammy" AKI
Stacking anticholinergics → delirium
Promethazine IV push → tissue necrosis
Metoclopramide in complete obstruction → perforation
Stopping gabapentin abruptly → seizure risk
📋 Quick Rounds Check
Pain score at rest + activity? Trend?
Acetaminophen scheduled? NSAID day count?
Bowel regimen ordered? Last BM?
Sleep hours? Melatonin ordered? No benzos?
CAM delirium screen done?
Anticholinergic burden count?
Renal function → dose adjustments needed?
Related Topics
Code Status & Advance DirectivesFamily Meeting FrameworkGoals of Care & Symptom ManagementHospice Eligibility CriteriaOpioid Rotation ConversionPalliative Extubation
EssentialWards
VTE Prophylaxis
Every inpatient needs VTE risk assessment. Padua score for medical patients. Caprini score for surgical. Pharmacologic (LMWH preferred) unless contraindicated. Mechanical (SCDs) if bleeding risk. "Did you order the DVT ppx?" -yes, always.
VTE prophylaxis is one of the most impactful things you order every day. Hospital-acquired VTE is preventable. Not ordering prophylaxis is a patient safety event.
Key Evidence: Enoxaparin 40 mg daily reduced VTE by 63% in acutely ill medical patients MEDENOX, 1999. Dalteparin reduced VTE in medical patients PREVENT, 2004. Fondaparinux reduced VTE in medical patients ARTEMIS, 2006. Extended post-discharge prophylaxis with rivaroxaban did not significantly reduce symptomatic VTE MARINER, 2018.
Special Populations
Population
Recommendation
Notes
Pregnancy
Enoxaparin preferred; avoid warfarin
Increased VTE risk in pregnancy + postpartum. Warfarin is teratogenic (crosses placenta).
Extended prophylaxis: Continue × 35 days post-op (not just until discharge).
At discharge: May switch to rivaroxaban 10 mg PO daily for convenience.
Key lesson: Hip and knee replacement require extended prophylaxis × 35 days. VTE risk persists well beyond hospitalization. Standard 10–14 days is insufficient.
📋 Case 3, CKD Patient (LMWH Contraindicated)
Patient: 68M with CKD stage 4 (CrCl 22 mL/min), admitted for CHF exacerbation.
Why LMWH is contraindicated: Enoxaparin is renally cleared. CrCl < 30 → drug accumulates → bleeding risk.
Order:
Heparin 5,000 units SC q8h (hepatic metabolism, not renally cleared)
SCDs (combination prophylaxis for added protection)
Key lesson: Always check CrCl before ordering enoxaparin. CrCl < 30 = use UFH. This is one of the most common prophylaxis errors on wards.
🚨 Management
Prophylaxis Options
Method
Option
Dose
Pharmacologic (preferred)
Enoxaparin (Lovenox)
40 mg SC daily (or 30 mg SC q12h if BMI > 40 or CrCl < 30 → use UFH)
Heparin (unfractionated)
5,000 units SC q8h (preferred if CrCl < 30 or high bleed risk -shorter half-life)
Mechanical
SCDs (sequential compression devices)
Both legs, worn whenever in bed
Extended prophylaxis
Rivaroxaban (Xarelto) or Enoxaparin (Lovenox)
Post-discharge for high-risk medical (MARINER) or post-surgical (hip/knee)
🔄 Updated Practice: Old teaching: sequential compression devices (SCDs) are equivalent to pharmacologic VTE prophylaxis. Current practice: pharmacologic prophylaxis (enoxaparin 40 mg SQ daily or heparin 5000 units SQ q8-12h) is superior to mechanical prophylaxis alone. SCDs should be used only when pharmacologic prophylaxis is contraindicated (active bleeding, severe thrombocytopenia). The combination of both is used in highest-risk patients (trauma, major orthopedic surgery).
Extended Prophylaxis Evidence: Hip/knee replacement: Extended prophylaxis x 35 days reduces VTE by ~60% RECORD, 2008. Cancer surgery: Extended LMWH x 4 weeks post-op reduces VTE ENOXACAN II, 2002. Medical patients: Extended prophylaxis NOT routinely recommended APEX, 2016EXCLAIM, 2010.
Contraindications to Pharmacologic Prophylaxis
Active bleeding
Severe thrombocytopenia (platelets < 50K)
Recent intracranial hemorrhage
Epidural/spinal anesthesia (hold LMWH around procedure)
HIT (heparin-induced thrombocytopenia) -use mechanical only or argatroban if treatment-dose needed
🧪 Workup
Padua Score (medical) or Caprini Score (surgical) -on admission
IMPROVE Bleed Score -if considering pharmacologic
Platelet count -< 50K → mechanical only
Creatinine/CrCl -CrCl < 30 → use UFH instead of LMWH
Review medications -anticoagulants already on board?
💊 Medications
Drug
Dose
Key Notes
Enoxaparin (Lovenox)
40 mg SC daily
Preferred LMWH. Predictable pharmacokinetics. No monitoring needed.
Heparin (UFH)
5,000 units SC q8h
Use if CrCl < 30, high bleed risk (shorter half-life), or obese patients.
Fondaparinux (Arixtra)
2.5 mg SC daily
Alternative if HIT. Factor Xa inhibitor. Renally cleared.
📋 On Rounds
Pimp Questions
Why is q8h UFH preferred over q12h for VTE prophylaxis?
Multiple meta-analyses show that 5,000 units SC q8h (TID) is superior to q12h (BID) for preventing VTE in medical patients. The difference is particularly significant for DVT prevention. Q8h maintains more consistent anti-Xa levels. The trade-off is slightly higher minor bleeding risk, but the VTE prevention benefit outweighs this.
When should you use UFH instead of LMWH for prophylaxis?
(1) CrCl < 30 mL/min -LMWH is renally cleared and accumulates → bleeding risk. UFH is metabolized by the reticuloendothelial system. (2) High bleeding risk -UFH has a shorter half-life (1–2h vs 4–5h for LMWH), so effects wear off faster if bleeding occurs. (3) Planned procedures -easier to manage perioperatively. (4) Morbid obesity -some guidelines recommend UFH q8h or adjusted LMWH dosing (enoxaparin 40 mg q12h for BMI > 40).
Why is LMWH preferred over UFH for VTE prophylaxis?
LMWH has more predictable pharmacokinetics, longer half-life allowing once daily dosing (vs q8h for UFH), lower risk of HIT, and no need for aPTT monitoring. RCTs have shown LMWH is at least as effective as UFH for VTE prevention. UFH is preferred only when LMWH is contraindicated: CrCl < 30 (LMWH accumulates), high bleed risk (shorter half-life advantage), or perioperative setting (easier to hold and reverse).
Should you hold DVT prophylaxis for a procedure?
Depends on the procedure and bleeding risk. LMWH: hold 12h before and resume 12h after low-bleed-risk procedures. For high-bleed-risk procedures: hold 24h before. UFH: hold 4–6h (shorter half-life is an advantage here). Neuraxial procedures (epidural/spinal): hold LMWH ≥12h before placement and ≥4h after catheter removal, risk of epidural hematoma is devastating.
What is the IMPROVE VTE score?
A validated risk assessment tool specifically for acutely ill medical patients that predicts 3-month VTE risk. Components: Previous VTE (+3), known thrombophilia (+2), lower limb paralysis (+2), active cancer (+2), ICU/CCU stay (+1), complete immobilization ≥1 day (+1), age ≥60 (+1). Score ≥ 4 = high risk → pharmacologic prophylaxis indicated.
What did the MEDENOX trial show?
MEDENOX, 1999: Enoxaparin 40 mg daily reduced VTE in acutely ill medical patients by 63% vs placebo. Established the standard prophylactic dose of enoxaparin 40 mg SC daily. The 20 mg dose was NOT effective - only 40 mg showed benefit. Landmark trial that changed practice for medical inpatient prophylaxis.
What is the evidence for extended VTE prophylaxis after hospital discharge?
MARINER, 2018: Rivaroxaban 10 mg x 45 days post-discharge did NOT significantly reduce symptomatic VTE in acutely ill medical patients. APEX, 2016: Betrixaban showed modest benefit. Extended prophylaxis is supported for orthopedic surgery (hip/knee x 35 days) but NOT routinely for medical patients.
What is the Caprini score and how does it differ from Padua?
Caprini is for SURGICAL patients. Assigns weighted points for risk factors (prior VTE, cancer, age, surgery type, immobility). Score determines prophylaxis intensity: 0 = ambulation only, 1-2 = SCDs, 3-4 = pharmacologic, ≥ 5 = pharmacologic + extended. Padua is for MEDICAL patients with threshold ≥ 4 for pharmacologic prophylaxis.
Why is fondaparinux safe in HIT?
Fondaparinux (Arixtra) is a synthetic pentasaccharide that inhibits factor Xa. Unlike UFH and LMWH, it does NOT bind to platelet factor 4 (PF4), so it does not trigger the HIT antibody response. Can be used for prophylaxis (2.5 mg SC daily) or treatment-dose anticoagulation in confirmed HIT as an alternative to argatroban or bivalirudin.
⚡ Summary
Assess Every Inpatient, Every Admission
Hospital-acquired VTE is preventable, and failing to order prophylaxis is a patient safety event, not an oversight. Risk assessment goes on the admission order set and gets revisited when the clinical picture changes.
Use the Right Score for the Right Patient
Padua for medical inpatients: 4 or more is high risk and earns pharmacologic prophylaxis. Caprini for surgical patients: 0 early ambulation, 1 to 2 mechanical, 3 to 4 pharmacologic, 5 or more pharmacologic plus mechanical. IMPROVE Bleed scores the other side of the ledger and pushes a high scorer to mechanical prophylaxis instead.
Default Regimen
Enoxaparin 40 mg SC daily is preferred: predictable kinetics, no monitoring, once-daily dosing. Unfractionated heparin 5,000 units SC q8h is the alternative when renal function is poor or bleeding risk is high, because its short half-life is easier to reverse and stop.
Mechanical Is a Fallback, Not an Equal
Old teaching treated SCDs as equivalent; they are not. Pharmacologic prophylaxis is superior in medical inpatients. Use SCDs alone only when anticoagulation is contraindicated, and switch to pharmacologic prophylaxis as soon as the bleeding risk resolves.
Adjust the Dose for the Patient
CrCl below 30: use UFH, since LMWH is renally cleared and accumulates. BMI above 40: standard 40 mg daily is likely subtherapeutic, so use enoxaparin 40 mg q12h or UFH 7,500 units q8h. Pregnancy: enoxaparin, never warfarin (teratogenic). Cancer: LMWH beats UFH.
The One Absolute Rule About Heparin
A history of HIT means no heparin product at all, neither unfractionated nor low molecular weight. Use mechanical prophylaxis or fondaparinux, which does not cross-react with HIT antibodies.
Know When Prophylaxis Continues After Discharge
Hip or knee replacement: 35 days, which cuts VTE by roughly 60% (RECORD). Major cancer surgery: 4 weeks of LMWH (ENOXACAN II). Selected high-risk medical patients may continue post-discharge (MARINER). The risk does not end at the hospital door, and most post-operative VTE presents after discharge.
Check Contraindications Before You Click Order
Active bleeding, platelets below 50,000, recent intracranial hemorrhage or neurosurgery, and an epidural catheter in place all block pharmacologic prophylaxis. These are almost always temporary, so document the reason and set a date to reassess rather than leaving the patient unprotected for the whole admission.
RoundsRx Infographic Series · #14 · General ICU Care · PDF 152 KB
Related Topics
Discharge Planning ChecklistFalls & Delirium PreventionPerioperative Medicine
High-YieldRheumatology
Seronegative Spondyloarthropathies
Group of inflammatory arthritides that are RF-negative, HLA-B27 associated. Includes ankylosing spondylitis, psoriatic arthritis, reactive arthritis, IBD-associated arthritis. Axial inflammation + enthesitis are hallmarks. NSAIDs first-line, then biologics.
Traditional DMARDs (methotrexate, sulfasalazine) do NOT work for axial disease. They only help peripheral joints. For axial SpA, go directly from NSAIDs → biologics (anti-TNF or anti-IL-17).
Methotrexate for peripheral PsA + skin disease. Apremilast (PDE4 inhibitor) for mild PsA when biologics are not appropriate. Neither works for axial disease.
Clinical Examples
📋 Case 1, Ankylosing Spondylitis
Patient: 24M presenting with 6 months of progressive low back pain and stiffness. Pain is worse in the morning (>1 hour of stiffness), improves with exercise, and wakes him in the second half of the night. No improvement with rest.
Workup:
HLA-B27: Positive
MRI SI joints: Bilateral sacroiliitis with bone marrow edema
CRP: Elevated at 28 mg/L
RF, anti-CCP: Negative (seronegative)
X-ray spine: Early syndesmophytes
Management:
Started on Indomethacin (Indocin) 50 mg TID, partial response after 4 weeks
Escalated to Adalimumab (Humira) 40 mg SC q2 weeks after failing 2 NSAIDs
TB screening (QuantiFERON) negative prior to biologic initiation
Ophthalmology referral for uveitis screening
Key lesson: Young male + inflammatory back pain + bilateral sacroiliitis + HLA-B27+ = classic ankylosing spondylitis. NSAIDs first, then skip DMARDs and go directly to anti-TNF for axial disease.
📋 Case 2, Psoriatic Arthritis
Patient: 45F with known psoriasis × 10 years, now presenting with painful swollen fingers, “sausage-like” left 3rd toe, and pitting of multiple fingernails.
Exam findings:
Dactylitis: Diffuse swelling of left 3rd toe
DIP joint tenderness: Bilateral 2nd and 3rd fingers
Started on Methotrexate (Trexall) 15 mg weekly (peripheral + skin disease)
Folic acid 1 mg daily supplementation
Inadequate response at 3 months → switched to Secukinumab (Cosentyx) 150 mg SC monthly
Baseline LFTs, CBC, Hep B/C screening before methotrexate
Key lesson: Psoriasis + DIP arthritis + dactylitis + nail changes = psoriatic arthritis. Methotrexate addresses both skin and peripheral joints. IL-17 inhibitors are excellent for both PsA and psoriasis.
📋 Case 3, Reactive Arthritis
Patient: 22M presenting 3 weeks after treated Chlamydia urethritis with acute right knee swelling, bilateral conjunctivitis, and persistent dysuria despite completed doxycycline course.
Naproxen (Aleve) 500 mg BID for joint inflammation
Doxycycline 100 mg BID × 7 days (re-treat underlying Chlamydia if not fully eradicated)
Ophthalmology referral for conjunctivitis monitoring
HLA-B27: Positive (prognostic, higher risk of chronicity)
Key lesson: Post-GU infection + triad of conjunctivitis/urethritis/arthritis = reactive arthritis. Treat the underlying infection + NSAIDs for arthritis. Most cases self-limited (3–6 months), but HLA-B27+ patients have higher risk of chronic/recurrent disease.
🧪 Workup
HLA-B27 -positive in 90% of AS, 70% reactive, 50% PsA. Not diagnostic alone (8% of general population is positive).
X-ray pelvis (SI joints) -sacroiliitis (sclerosis, erosions, fusion). May take years to appear.
MRI SI joints -bone marrow edema = early sacroiliitis. Gold standard for early disease.
First-line all SpA. Full-dose, continuous for axial disease.
Indomethacin (Indocin)
25–50 mg TID
Traditional NSAID for AS. Very effective but GI side effects.
Adalimumab (Humira)
40 mg SC q2 weeks
Anti-TNF. First biologic for axial or peripheral SpA failing NSAIDs.
Secukinumab (Cosentyx)
150 mg SC monthly
Anti-IL-17. Alternative to anti-TNF. Avoid in IBD (can worsen).
Sulfasalazine (Azulfidine)
1–1.5 g BID
Peripheral joints only. No axial benefit.
📋 On Rounds
Pimp Questions
How do you differentiate inflammatory back pain from mechanical back pain?
Inflammatory: Age of onset < 40, insidious onset, morning stiffness > 30 min, improves with exercise, worse with rest, night pain (second half of night), alternating buttock pain. Mechanical: Any age, often acute onset, worse with activity, better with rest, no morning stiffness. Having 4+ inflammatory features has ~95% specificity for SpA. The key differentiator: inflammatory back pain gets BETTER with movement, mechanical gets WORSE.
Why are traditional DMARDs ineffective for axial SpA?
The pathophysiology of axial SpA involves entheseal inflammation and new bone formation at the spine/SI joints driven primarily by IL-17 and TNF pathways, not the same T-cell/B-cell mediated pathways targeted by traditional DMARDs (methotrexate, sulfasalazine). These drugs act on synovial inflammation (peripheral joints) but cannot penetrate or modulate the entheseal/axial inflammatory process.
What imaging finding differentiates ankylosing spondylitis from mechanical back pain?
Sacroiliitis on MRI is the key differentiator. MRI shows bone marrow edema (bright on STIR/T2 fat-sat sequences) at the sacroiliac joints, representing active inflammation, this is the gold standard for early AS before X-ray changes appear. X-ray findings of sacroiliitis (sclerosis, erosions, joint space narrowing, eventual fusion) may take years to develop. In contrast, mechanical back pain shows no SI joint inflammation on MRI.
Why are IL-17 inhibitors contraindicated in IBD-associated spondyloarthropathy?
IL-17 plays a paradoxical protective role in gut mucosal immunity. While IL-17 drives inflammation in the joints and spine, it is critical for maintaining the intestinal epithelial barrier and defense against gut pathogens. Blocking IL-17 with secukinumab or ixekizumab disrupts this protective function, leading to new-onset or exacerbation of IBD (both Crohn’s and UC).
⚡ Summary
What Ties the Group Together
Rheumatoid factor negative, HLA-B27 associated, with axial inflammation and enthesitis as the hallmarks. The family is ankylosing spondylitis, psoriatic arthritis, reactive arthritis and IBD-associated arthritis, plus undifferentiated disease that may evolve into one of them. Enthesitis, inflammation where tendon meets bone, is what distinguishes this group from rheumatoid arthritis, which inflames synovium.
Recognize Inflammatory Back Pain
Onset before age 45, insidious, lasting over 3 months, with morning stiffness beyond 30 min, improvement with exercise and not with rest, and night pain that wakes the patient in the second half of the night.That pattern is the opposite of mechanical back pain, and it is the single most useful piece of history in the whole topic.
Image the Sacroiliac Joints
Bilateral, symmetric sacroiliitis is the earliest and most characteristic finding.Plain films are normal for years, so a normal x-ray does not exclude disease. MRI shows bone marrow edema and diagnoses non-radiographic axial SpA, which is the same disease before structural change appears.
HLA-B27 Supports, It Does Not Diagnose
Present in about 90% of ankylosing spondylitis but also in 6 to 8% of the healthy population.A positive result in a patient with mechanical back pain means nothing, and a negative result does not exclude the diagnosis. Use it to raise or lower probability in a patient who already has inflammatory features.
Traditional DMARDs Fail in Axial Disease
Methotrexate and sulfasalazine do not work for spinal disease. They only help peripheral joints.For axial SpA go from NSAIDs straight to a biologic, an anti-TNF or an anti-IL-17 agent. Prescribing methotrexate for back pain in ankylosing spondylitis wastes months of a window in which fusion is still preventable.
NSAIDs Are First Line and Genuinely Disease-Modifying Here
Continuous rather than as-needed dosing may slow radiographic progression in axial disease, which is not true of NSAIDs in other arthritides. Physical therapy and posture-focused exercise are not optional adjuncts: they preserve the spinal mobility that fusion takes away permanently.
Recognize the Subtypes at the Bedside
Psoriatic arthritis: asymmetric oligoarthritis, DIP involvement, dactylitis (sausage digits), nail pitting and onycholysis. Reactive arthritis: asymmetric lower-limb oligoarthritis 1 to 4 weeks after a GI (Salmonella, Shigella, Campylobacter, Yersinia) or genitourinary (Chlamydia) infection, with the classic conjunctivitis, urethritis and arthritis triad. IBD-associated: peripheral disease follows bowel activity, axial disease does not.
Do Not Miss the Extra-Articular Disease
Anterior uveitis is the commonest extra-articular manifestation and is an ophthalmologic emergency: a red, painful, photophobic eye needs same-day slit-lamp assessment, not a wait-and-see. Also screen for aortic insufficiency and conduction disease, apical pulmonary fibrosis, and osteoporosis with an increased fracture risk. A fused cervical spine fractures with minimal trauma and is unstable, so any neck pain after a fall in ankylosing spondylitis needs CT, not plain films.
RoundsRx Infographic Series · #167 · Rheumatology · PDF 141 KB
Text version
RHEUMATOLOGY · One Pager
Seronegative Spondyloarthropathies
RF-negative, HLA-B27-associated inflammatory arthritis where enthesitis and axial inflammation are the hallmarks. Every treatment decision starts with one question: is this axial or peripheral disease?
🧪 Recognize It
Inflammatory back pain: onset < 40, insidious, morning stiffness > 30 min, improves with exercise, worse with rest, night pain in the second half of the night. Mechanical pain does the opposite: worse with activity, better with rest. 4+ inflammatory features is ~95% specific for SpA.
Enthesitis: inflammation at tendon/ligament insertions (Achilles, plantar fascia). This is the lesion that traditional DMARDs cannot reach.
Dactylitis: "sausage digit", diffuse swelling of an entire finger or toe rather than one joint.
Seronegative: RF and anti-CCP negative. Check them to confirm, not to diagnose.
HLA-B27: AS ~90%, reactive ~70%, PsA ~50%. Not diagnostic alone, since 8% of the general population is positive.
Extra-articular: uveitis, psoriasis, IBD. Anterior uveitis is the #1 extra-articular manifestation of AS, so refer to ophthalmology.
⚡ The Subtypes
Ankylosing spondylitis: inflammatory back pain, bilateral symmetric sacroiliitis, progressive spinal fusion ("bamboo spine"), enthesitis. Watch for anterior uveitis, aortic insufficiency, apical pulmonary fibrosis, IgA nephropathy, cauda equina syndrome.
Psoriatic arthritis: asymmetric oligoarthritis, DIP joints, dactylitis, arthritis mutilans with "pencil-in-cup" deformity. Nail pitting and onycholysis are the tell when the plaques are hidden (scalp, intergluteal cleft).
Reactive arthritis: asymmetric lower-extremity large-joint oligoarthritis starting 1–4 weeks after GI (Salmonella, Shigella, Campylobacter, Yersinia) or GU (Chlamydia trachomatis) infection. Triad: "can't see, can't pee, can't climb a tree", conjunctivitis/uveitis + urethritis/cervicitis + arthritis. Also keratoderma blennorrhagica and circinate balanitis. Most cases self-limited over 3–6 months, but HLA-B27+ patients have a higher risk of chronic or recurrent disease.
IBD-associated arthritis: peripheral disease follows IBD activity, axial disease runs independent of it. Also erythema nodosum, pyoderma gangrenosum, uveitis, PSC (in UC).
Undifferentiated SpA: SpA features not meeting any subtype's criteria. May evolve into AS or PsA over time, so keep re-examining.
🚨 Treatment Ladder: Axial vs Peripheral
1
NSAIDs first, both phenotypes: indomethacin 25–50 mg TID or naproxen 500 mg BID. Try at least 2 different NSAIDs, each for 2–4 weeks at full dose, before calling it a failure. Continuous rather than as-needed dosing for axial disease. Peripheral disease can also get local steroid injection.
2
Axial: skip the DMARDs entirely and go to anti-TNF. Adalimumab 40 mg SC q2wk, etanercept 50 mg SC weekly, or infliximab 5 mg/kg IV q6–8wk. Axial disease is driven by entheseal inflammation and new bone formation through IL-17 and TNF pathways, not the synovial inflammation traditional DMARDs act on, so methotrexate and sulfasalazine simply do not work above the pelvis.
2
Peripheral: DMARDs are the step 2. Methotrexate 15–25 mg weekly (covers skin plus peripheral joints in PsA, give with folic acid) or sulfasalazine 1–1.5 g BID. Apremilast 30 mg BID is an option for mild PsA when biologics are not appropriate. None of these help axial disease.
3
IL-17 inhibitors: secukinumab 150 mg SC monthly or ixekizumab 80 mg SC q4wk, as an alternative to anti-TNF or after anti-TNF failure. Excellent for both PsA joints and psoriatic skin.
4
Before any biologic: screen for TB and hepatitis B, because anti-TNF reactivates latent infection. Get baseline LFTs, CBC, and hepatitis B/C screening before methotrexate. Monitor for infection on therapy.
💊 Key Drugs
Naproxen (Aleve)500 mg BID, first-line all SpA; full-dose and continuous for axial disease
Indomethacin (Indocin)25–50 mg TID, traditional NSAID for AS, very effective but GI side effects
Adalimumab (Humira)40 mg SC q2 weeks, first biologic for axial or peripheral SpA failing NSAIDs
Secukinumab (Cosentyx)150 mg SC monthly, anti-IL-17 alternative to anti-TNF; avoid in IBD
Methotrexate (Trexall)15–25 mg weekly, peripheral PsA plus skin disease; no axial benefit
Sulfasalazine (Azulfidine)1–1.5 g BID, peripheral joints only, no axial benefit
Apremilast (Otezla)30 mg BID, PDE4 inhibitor for mild PsA when biologics are not appropriate
📊 Workup and Monitoring
MRI SI joints is the gold standard for early disease: bone marrow edema on STIR/T2 fat-sat means active sacroiliitis, and it turns positive years before the X-ray does.
X-ray pelvis for sacroiliitis (sclerosis, erosions, fusion), but a normal film does not exclude AS since changes may take years to appear.
X-ray spine for syndesmophytes and bamboo spine, findings of late AS.
CRP and ESR may be elevated and help track inflammatory activity, but normal values do not rule out active disease.
RF and anti-CCP to confirm the seronegative phenotype and exclude RA.
Skin and nail exam every visit: nails, scalp, intergluteal fold, the places psoriasis hides and reclassifies the patient as PsA.
TB screening (QuantiFERON) before starting a biologic and per protocol thereafter.
⚠️ Pitfalls
Prescribing methotrexate or sulfasalazine for axial disease. They only help peripheral joints. For axial SpA the path is NSAIDs straight to a biologic; sending the patient through a DMARD trial just loses months.
IL-17 inhibitors in IBD-associated SpA. IL-17 is protective in gut mucosa and maintains the intestinal epithelial barrier, so blocking it can trigger or worsen Crohn disease and UC. Use anti-TNF in that group.
Escalating after one NSAID. The bar is at least 2 NSAIDs at full dose for 2–4 weeks each before declaring NSAID failure.
Using HLA-B27 as a diagnostic test. 8% of the general population is positive; it supports the picture and carries prognostic weight in reactive arthritis, but it does not make the diagnosis.
Starting a biologic without TB and hepatitis B screening.
🏥 Escalate / Refer When
Axial disease with inadequate response to 2 full-dose NSAID trials: escalate directly to anti-TNF, do not detour through DMARDs.
Peripheral PsA with inadequate response to methotrexate at 3 months: switch to an IL-17 inhibitor or anti-TNF.
Any red eye, eye pain, or visual change: ophthalmology, anterior uveitis is the most common extra-articular manifestation of AS and needs prompt treatment.
New neurologic deficit or bladder/bowel dysfunction in AS: cauda equina syndrome is a recognized AS complication and is a surgical emergency.
New murmur or dyspnea in AS: evaluate for aortitis with aortic insufficiency and apical pulmonary fibrosis.
Reactive arthritis after Chlamydia: treat or re-treat the underlying infection alongside NSAIDs, and refer to ophthalmology for conjunctivitis monitoring.
🎓 The Three Things to Remember
Axial versus peripheral is the fork in the road. It determines whether DMARDs have any role at all.
Inflammatory back pain gets better with movement, mechanical back pain gets worse. That single question sorts most referrals.
MRI SI joints beats X-ray for early disease, so a young patient with inflammatory back pain and a normal pelvis film still needs the MRI before you accept a mechanical label.
Pro tips:
• Problem-based A&P is key
• Include disposition plan every day
• Copy-forward is dangerous -always update exam and labs
• DVT ppx, diet, activity, code status -address daily
• Less is more -focused > 10-page novel
📟
Handling Pages & Cross-Cover
When paged: Get patient name, room, nurse, problem. Pull chart. Go see the patient. Document.
Common pages:
• Fever: Cultures (blood/urine), CXR, exam
• Pain: Acetaminophen → NSAID → opioid
• Insomnia: Melatonin → trazodone. Avoid benzos.
• HTN: Symptomatic? Asymptomatic HTN rarely needs emergent Rx
• Hypoglycemia: D50 if < 70 and symptomatic. Recheck 15 min.
• Fall: Neuro exam, CT head if on anticoag
• Chest pain: ECG, troponin, compare to prior
💡
Day One Survival Tips
Before day one: EMR access, know how to page, bring phone charger
On wards:
• Pre-round early -see patients before rounds
• Write your plan before rounds
• Carry a patient list with key info
• Ask for help -seniors expect and respect it
• "I don't know, but I'll look it up" is always acceptable
• Sign out clearly
For your sanity:
• Eat when you can, sleep when you can
• Imposter syndrome is universal -you belong here
• Your co-interns are your best resource
🏥
Admission Orders: ADC VANDALISM
Admit to: floor/tele/ICU Diagnosis Condition: stable/guarded/critical Vitals: frequency Allergies: verify Nursing: I&Os, weights, precautions Diet: regular/cardiac/NPO Activity: bed rest/ambulate Labs: AM labs, trending IV fluids: type, rate Special: DVT ppx, GI ppx, bowel regimen Medications: home meds + new meds
🔑
Key Numbers to Save Day One
• Rapid Response / Code Blue
• Pharmacy
• Blood Bank
• Radiology
• IR (Interventional Radiology)
• Lab
• Social Work / Case Management
• Chaplain / Spiritual Care
• Your senior resident / chief -always your first call when unsure
Clinical Tools
✅ Rounding Checklists
Structured checklists to ensure nothing is missed. Print-friendly. Based on patient safety evidence.
🫁 ICU Daily Checklist
ABCDEF Bundle + Safety Checks
☐ A -Analgesia/Sedation: RASS goal? Pain score?
☐ B -SAT & SBT: Daily awakening + breathing trials
☐ C -Sedation choice: Avoid benzos if possible
☐ D -Delirium: CAM-ICU assessment
☐ E -Early mobility: OOB? PT/OT?
☐ F -Family: Updated? Meeting needed?
☐ Lines -still needed? Date? Dressing?
☐ Tubes -Foley needed? NGT?
☐ DVT ppx ordered
☐ GI ppx (stress ulcer) if indicated
☐ HOB 30° (VAP prevention)
☐ Glucose target < 180
☐ Nutrition -enteral feeds within 48h
☐ Bowel regimen -last BM?
☐ Daily goals -what needs to happen today?
🏥 Floor/Wards Daily Checklist
Pre-rounding + Safety
☐ Overnight events / pages
☐ Patient subjective -how do they feel?
☐ Vitals trend -fever curve, BP, HR
☐ Focused exam
☐ New labs / imaging results
☐ DVT ppx ordered
☐ Diet appropriate
☐ Activity -OOB? PT/OT?
☐ Foley -still needed?
☐ IV → PO conversion possible?
☐ Home meds restarted or held for reason?
☐ Bowel regimen (especially on opioids)
☐ Code status confirmed
☐ Disposition -discharge date? Barriers?
☐ Patient education -understanding?
🚪 Admission Checklist
Every new admission
☐ H&P completed
☐ Admission orders (ADC VANDALISM)
☐ DVT prophylaxis ordered
☐ Home med reconciliation
☐ Allergies verified
☐ Code status discussed
☐ Diet ordered
☐ IV fluids if needed
☐ AM labs ordered
☐ Telemetry if indicated
☐ Fall risk assessed
☐ Isolation precautions if needed
☐ Consults placed
☐ Patient/family updated
☐ Sign-out prepared
🏠 Discharge Checklist
Safe transitions of care
☐ Medication reconciliation
☐ Prescriptions sent to pharmacy
☐ Patient can afford meds
☐ Follow-up appointments scheduled
☐ Discharge summary completed
☐ Patient education (teach-back)
☐ Red flag symptoms explained
☐ Pending results -who follows up?
☐ Home services ordered if needed
☐ DME ordered if needed
☐ Transportation arranged
☐ PCP notified
☐ Post-discharge call scheduled (48-72h)
Hands-On Skills
🩺 Procedure Guides
Step-by-step bedside procedure references. Indications, contraindications, landmarks, technique, and complications. Not a substitute for supervised training.
🔴
Central Venous Catheter (Central Line)
IJ, Subclavian, Femoral -Seldinger technique under ultrasound guidance
• Infection at insertion site
• Thrombus in target vessel
• Subclavian: avoid if coagulopathic (non-compressible)
• IJ: caution with ↑ ICP (Trendelenburg worsens ICP)
• Femoral: higher infection rate -use only if IJ/subclavian not feasible
Technique (IJ -Most Common)
1. Consent, time-out, full barrier precautions (cap, mask, sterile gown, gloves, full drape)
2. Position: Trendelenburg, head turned away
3. Ultrasound: Identify IJ (compressible) lateral to carotid (pulsatile, non-compressible)
4. Prep & drape -chlorhexidine, wide sterile field
5. Lidocaine -local anesthesia at insertion site
6. Access: 18G needle under US guidance, confirm venous blood (dark, non-pulsatile)
7. Guidewire -advance through needle, watch on US, confirm no arrhythmia on monitor
8. Nick skin with scalpel, dilator over wire
9. Thread catheter over wire -never let go of the wire!
10. Remove wire, flush all ports, suture, dressing
11. CXR -confirm tip at cavoatrial junction, rule out pneumothorax
⚠️ Complications
Pneumothorax (subclavian > IJ), arterial puncture, air embolism, arrhythmia (wire in heart), infection (CLABSI), thrombosis. Never advance against resistance.
🟠
Arterial Line
Radial (preferred), femoral, brachial -continuous BP monitoring and frequent ABGs
Indications
• Continuous BP monitoring (hemodynamic instability, vasopressors)
• Frequent ABG sampling
• Intra-operative monitoring (cardiac surgery, major procedures)
• BP cuff unreliable (morbid obesity, arrhythmia)
Pre-Procedure
• Modified Allen test -confirm dual blood supply (radial + ulnar) before radial art line
• Compress both radial and ulnar arteries → release ulnar → hand should pink up in < 7 seconds
• If Allen test negative (no collateral flow) → use other wrist or femoral
Technique (Radial)
1. Position: Wrist dorsiflexed 20–30° over towel roll, tape hand to arm board
2. Prep: Chlorhexidine, sterile drape
3. Lidocaine: Small wheal over radial pulse
4. US-guided (recommended) or palpation
5. 20G catheter-over-needle at 15–30° angle, advance until flash of arterial blood (pulsatile, bright red)
6. Advance catheter off needle into artery, remove needle
7. Connect to transducer, level at phlebostatic axis (4th ICS, mid-axillary)
8. Confirm waveform -arterial waveform with dicrotic notch
⚠️ Complications
Hematoma, thrombosis, distal ischemia (rare with good Allen test), infection, pseudoaneurysm. Never flush forcefully -risk of retrograde embolism to brain.
🟡
Lumbar Puncture (LP)
Diagnostic and therapeutic -meningitis, SAH, idiopathic intracranial hypertension
• ↑ ICP with mass lesion -get CT head BEFORE LP if: papilledema, focal neuro deficits, altered consciousness, immunocompromised, age > 60, seizure within 1 week
• Skin infection at puncture site
• Severe coagulopathy (INR > 1.5, platelets < 50K)
• Spinal epidural abscess
CSF Interpretation
Bacterial: ↑ WBC (>1000, PMN predominant), ↑ protein, ↓ glucose, + Gram stain Viral: ↑ WBC (10-500, lymphocyte predominant), normal/↑ protein, normal glucose TB/fungal: ↑ WBC (lymphocytes), ↑ protein, ↓↓ glucose SAH: RBCs that do NOT clear (tube 1 vs tube 4), xanthochromia Normal: OP 6-20 cmH₂O, WBC < 5, protein 15-45, glucose 40-70
Technique
1. Position: Lateral decubitus (fetal position) or seated, spine flexed. Lateral decubitus preferred for opening pressure measurement.
2. Landmark: L3-L4 or L4-L5 interspace (iliac crest line = L4 spinous process). Always below L2 (conus medullaris ends at L1-L2).
3. Prep: Chlorhexidine, sterile drape
4. Lidocaine: Local anesthesia (subcutaneous + deeper tissues along planned needle path)
5. Spinal needle (20-22G, atraumatic tip preferred -reduces post-LP headache): advance midline with bevel parallel to longitudinal fibers of dura, angled slightly cephalad
6. Feel the "pop" through ligamentum flavum and dura
7. Remove stylet -CSF should flow
8. Opening pressure -measured with manometer in lateral decubitus. Normal: 6-20 cmH₂O
9. Collect tubes: Tube 1 (cell count), Tube 2 (glucose, protein), Tube 3 (Gram stain, culture, extras), Tube 4 (cell count -compare to tube 1 for traumatic tap)
10. Replace stylet before removing needle (reduces post-LP headache risk)
⚠️ Post-LP Headache
Positional headache (worse upright, better supine) in ~10-30%. Reduce risk: atraumatic needle, smaller gauge, replace stylet before removal. Treatment: caffeine, analgesics, and if severe → epidural blood patch (definitive).
🟢
Paracentesis
Diagnostic and therapeutic -ascites evaluation, large-volume removal
Indications
• Diagnostic: New-onset ascites, rule out SBP (all cirrhotics admitted with ascites should get diagnostic para)
• Therapeutic: Tense ascites causing respiratory compromise, abdominal discomfort
Key Studies to Send
• Cell count with differential -PMN ≥ 250 = SBP (treat empirically with ceftriaxone)
• Albumin -calculate SAAG (serum albumin - ascites albumin). SAAG ≥ 1.1 = portal hypertension
• Total protein
• Culture -inoculate blood culture bottles at bedside (higher yield)
• Glucose, LDH, amylase, cytology -if secondary peritonitis or malignancy suspected
Technique
1. Position: Supine, slightly tilted to side of puncture
2. Site: LLQ (preferred) -2 fingerbreadths medial and cephalad to ASIS. Avoid surgical scars, visible vessels, rectus sheath
3. US guidance -confirm fluid pocket ≥ 2 cm, mark site
4. Prep: Chlorhexidine, sterile drape
5. Lidocaine: All layers including peritoneum
6. Z-track technique -pull skin 2 cm caudally before inserting needle (reduces post-procedure leak)
7. Insert needle/catheter while aspirating, advance until fluid returns
8. Collect samples or connect to vacuum bottles for large-volume
9. Large-volume (> 5L): Give albumin 6-8g per liter removed (prevents post-paracentesis circulatory dysfunction)
⚠️ Key Points
Do NOT correct coagulopathy before paracentesis in cirrhosis. INR/platelets do not predict bleeding risk in liver disease (rebalanced hemostasis). Routine transfusion of FFP/platelets is NOT indicated. SBP: PMN ≥ 250 → start ceftriaxone (Rocephin) 2g IV daily empirically, don't wait for culture.
🔵
Thoracentesis
Diagnostic and therapeutic -pleural effusion evaluation and drainage
Indications
• Diagnostic: Any new or unexplained pleural effusion
• Therapeutic: Symptomatic (dyspnea) effusion
• Exception: bilateral small effusions in known CHF responding to diuretics -can observe without tapping
Light's Criteria (Exudate if ANY met)
• Pleural protein / serum protein > 0.5
• Pleural LDH / serum LDH > 0.6
• Pleural LDH > 2/3 upper limit of normal serum LDH
1. Preparation: Equipment check (ETT sizes 7.0-8.0, laryngoscope, suction, BVM, bougie, backup airway -LMA), monitors on, IV access 2. Pre-oxygenation: 100% FiO₂ × 3-5 min (NRB at 15L/min or flush rate). Apneic oxygenation via nasal cannula at 15L during attempt 3. Pre-treatment: Consider fentanyl (Sublimaze) 1-3 mcg/kg for sympathetic response 4. Paralysis with induction: Induction agent + paralytic simultaneously 5. Protection/Positioning: Sniffing position (ear to sternal notch alignment). Cricoid pressure (Sellick) -controversial 6. Placement: Direct/video laryngoscopy. Visualize cords, pass ETT, confirm with ETCO₂ 7. Post-intubation: CXR, vent settings, sedation, secure tube
RSI Medications
Induction agents:
• Ketamine (Ketalar) 1-2 mg/kg IV -hemodynamically stable, bronchodilator. First choice in asthma/sepsis
• Etomidate (Amidate) 0.3 mg/kg IV -hemodynamically neutral. Adrenal suppression (single dose is safe)
• Propofol (Diprivan) 1-2 mg/kg IV -↓ BP, ↓ ICP. Avoid in hypotension
Paralytics:
• Succinylcholine (Anectine) 1.5 mg/kg IV -fastest onset (45-60 sec), shortest duration (6-10 min). Avoid in hyperkalemia, burns > 48h, crush injury, neuromuscular disease
• Rocuronium (Zemuron) 1.2 mg/kg IV -onset 60-90 sec, duration 45-60 min. Reversible with sugammadex (Bridion). Preferred if succinylcholine contraindicated
⚠️ Confirmation
End-tidal CO₂ (ETCO₂) is the ONLY reliable confirmation of ETT placement. Auscultation alone is NOT sufficient. No ETCO₂ = esophageal intubation until proven otherwise → remove tube and re-attempt. CXR confirms position but NOT placement (takes too long).
Quick Reference
💧 IV Fluids Guide
Which fluid, when, and why. The most common order you'll write -make sure you understand what each fluid does.
Fluid
Na⁺
Cl⁻
K⁺
Buffer
Osmolarity
% Stays Intravascular
When to Use
Normal Saline (0.9% NaCl)
154
154
0
None
308
~25%
Volume resuscitation, hyponatremia, hyperkalemia. Caution: hyperchloremic metabolic acidosis and increased AKI risk with large volumes (SMART, 2018 -NS increased composite of death, new RRT, or persistent renal dysfunction vs balanced crystalloids).
Lactated Ringer's (LR)
130
109
4
Lactate 28
273
~25%
Preferred resuscitation fluid. More physiologic. Less acidosis than NS. Contains 4 mEq/L K⁺, which is clinically insignificant: the small potassium load is outweighed by avoiding the hyperchloremic acidosis that saline causes, which itself shifts K⁺ out of cells. LR is safe in hyperkalemiaSMART, 2018, though that trial found similar rates of hyperkalemia in both arms rather than superiority for LR.
D5W (5% Dextrose)
0
0
0
None
252
~8%
Free water. Hypernatremia correction, medication diluent. NOT for resuscitation (distributes to total body water).
D5 1/2 NS
77
77
0
None
406
~17%
Maintenance fluid. Provides free water + some Na. Common maintenance choice.
D5 NS
154
154
0
None
560
~25%
Maintenance with higher Na. DKA (when glucose < 250, switch from NS to D5NS).
3% Hypertonic Saline
513
513
0
None
1026
>100%
Severe symptomatic hyponatremia (seizure, coma). 100 mL bolus. Also for ↑ ICP in TBI. Often needs central line.
Common shortcut: Most adults get 75–125 mL/hr maintenance. Adjust for heart failure (restrict), renal failure, and ongoing losses.
🚫 Common Mistakes
• NS for everything → hyperchloremic acidosis. Use LR when possible.
• D5W for resuscitation → it's free water, not volume expander. Only ~8% stays intravascular.
• Forgetting K⁺ in maintenance → add 20 mEq KCl/L to maintenance fluids (unless hyperkalemic or renal failure).
• Running maintenance in volume-overloaded CHF → if they're eating, they don't need IV fluids!
• Not adjusting for renal failure → reduce rate. They can't clear the volume.
• LR in hyperkalemia → contains 4 mEq/L K⁺. Use NS instead.
Quick Reference
🩸 Transfusion Guide
Blood product thresholds, transfusion reactions, and special considerations. Know when to transfuse and when to hold.
Before transfusing:
• Type & screen on file? (valid 72h at most institutions)
• Consent obtained?
• Two-nurse verification at bedside (check patient ID, blood band, product label)
• Pre-medicate with acetaminophen ± diphenhydramine if prior reactions
During transfusion:
• Vitals at: baseline, 15 min, 30 min, 1 hour, completion
• pRBCs: infuse over 1–2 hours (max 4 hours per unit)
• Give furosemide (Lasix) 20mg IV between units if CHF risk
• STOP transfusion for: fever > 1°C, rigors, hypotension, chest pain, dyspnea, dark urine
Special situations:
• Jehovah's Witness: Respect refusal. Document clearly. Cell saver may be acceptable.
• Massive transfusion: 1:1:1 ratio. Calcium with every 4 units. Warm products.
• Irradiated products: Required for immunocompromised (BMT, Hodgkin, intrauterine transfusion) -prevents TA-GVHD
• CMV-negative: For CMV-negative transplant recipients and pregnant women
RoundsRx Infographic Series · #138 · Hematology · PDF 145 KB
Quick Reference
💓 ECG Pattern Guide
High-yield ECG patterns every resident must recognize. Organized by clinical urgency. When in doubt, compare to prior ECGs and get a 12-lead.
🚨 Emergent -Act Immediately
STEMI
ST-Elevation Myocardial Infarction
Pattern: ST elevation ≥ 1mm in ≥ 2 contiguous leads (≥ 2mm in V1-V3 for men) Morphology: Concave-up ("tombstone") or convex-up ST elevation with reciprocal ST depression in opposite leads
Progression:
• K⁺ 5.5-6.5: Peaked T waves (tall, narrow, symmetric -earliest sign)
• K⁺ 6.5-7.5: Prolonged PR → flattened P waves → widened QRS
• K⁺ 7.5-8.0: Sine wave pattern (QRS merges with T wave)
• K⁺ > 8.0: VF → asystole
Action: Calcium gluconate 1g IV immediately (stabilizes membrane). Then insulin + D50 to shift K⁺. See Hyperkalemia topic for full protocol.
Complete Heart Block (3rd Degree)
No atrial impulses conduct to ventricles
Pattern: P waves and QRS complexes completely independent (AV dissociation). Regular P-P intervals. Regular R-R intervals. But NO relationship between them.
Escape rhythm:
• Junctional escape (narrow QRS, 40-60 bpm) → more stable
• Ventricular escape (wide QRS, 20-40 bpm) → unstable, high risk of asystole
Action: Atropine 1mg IV (may not work if infranodal). Transcutaneous pacing. Cardiology for transvenous pacer. Dopamine or epinephrine drip as bridge.
⚠️ Urgent -Requires Prompt Attention
Wellens Syndrome
Critical LAD stenosis -will STEMI if missed
Pattern: Deep symmetric T-wave inversions (Type A, more common) or biphasic T waves (Type B) in V2-V3 (± V1, V4-V6)
Key: Seen during pain-FREE interval (not during active chest pain). During pain, ST may be elevated.
Critical point: Do NOT stress test -will STEMI on the treadmill. Needs cath.
Action: Admit, anticoagulate, cardiology consult for cath. Medical management until intervention.
Brugada Syndrome
Risk of sudden cardiac death in structurally normal heart
Type 1 (diagnostic): Coved ST elevation ≥ 2mm in V1-V3 with T-wave inversion. "Shark fin" morphology. Type 2 (suggestive): Saddleback ST elevation in V1-V3. Not diagnostic alone -needs provocation test (ajmaline/procainamide).
Key features: Young male, Asian descent, family history of sudden death, syncope, nocturnal agonal breathing.
Action: EP consult. ICD is the only proven therapy (no drug prevents VF in Brugada). Avoid fever (unmasks pattern), avoid Class I antiarrhythmics.
Prolonged QTc
Risk of Torsades de Pointes
Normal: < 440ms (men), < 460ms (women) Concerning: > 480ms Dangerous: > 500ms → high risk for Torsades de Pointes (TdP)
Classic (but uncommon): S1Q3T3 -deep S in lead I, Q wave + T inversion in lead III. Present in only ~20% of PE.
More common findings:
• Sinus tachycardia (#1 finding -most sensitive)
• Right axis deviation
• T-wave inversions in V1-V4 (RV strain pattern)
• New RBBB or incomplete RBBB
• Atrial fibrillation (new onset)
Remember: A normal ECG does NOT rule out PE. ECG is often normal in PE.
Action: If PE suspected → Wells score → D-dimer or CT-PA. See PE topic.
📋 Important Patterns to Recognize
Atrial Fibrillation
Irregularly irregular -most common sustained arrhythmia
Pattern: No P waves (fibrillatory baseline), irregularly irregular R-R intervals, narrow QRS (unless aberrancy/BBB)
Distinguish from:
• Atrial flutter: Regular, sawtooth P waves (especially II, III, aVF), often 150 bpm (2:1 block)
• MAT: ≥ 3 different P-wave morphologies, irregular, associated with COPD/hypoxia
Action: Rate control (metoprolol (Lopressor) or diltiazem (Cardizem)). CHA₂DS₂-VASc for anticoagulation. See Afib topic.
Pericarditis
Diffuse ST elevation -NOT a STEMI
Pattern: Diffuse concave-up ST elevation in nearly ALL leads + PR depression (especially II) + ST depression in aVR
Distinguish from STEMI:
• Pericarditis: diffuse (many territories), NO reciprocal changes, PR depression, concave-up
• STEMI: localized (one territory), reciprocal changes present, often convex-up
Key: PR depression in lead II is nearly pathognomonic for pericarditis.
Action: NSAIDs + colchicine (Colcrys). Echo to rule out effusion/tamponade. Do NOT give thrombolytics (not a STEMI!).
Heart Blocks (1st, 2nd degree)
AV conduction delays
1st degree: Prolonged PR > 200ms. Every P conducts. Usually benign -no treatment.
2nd degree Type I (Wenckebach): Progressive PR prolongation → dropped beat → cycle repeats. Usually nodal. Often benign.
2nd degree Type II (Mobitz II): Constant PR interval with sudden dropped QRS (no warning). Infranodal. High risk of progressing to complete heart block. Needs pacemaker.
Key rule: Wenckebach = watch. Mobitz II = pacer.
Bundle Branch Blocks
QRS > 120ms -which bundle is blocked?
RBBB: rsR' ("bunny ears") in V1-V2, wide S in I/V6. Mnemonic: "MaRRoW" -V1 has R (tall R'), V6 has W (wide S).
LBBB: Broad notched R in I/V6, deep QS or rS in V1. Mnemonic: "WiLLiaM" -V1 has W (QS), V6 has M (notched R).
Clinical significance:
• RBBB: Can be normal. New RBBB in ACS/PE → concerning.
• LBBB: Almost always pathological. New LBBB + chest pain → treat as STEMI equivalent (Sgarbossa criteria). Old LBBB makes STEMI diagnosis difficult.
Sgarbossa criteria (STEMI in LBBB): Concordant ST elevation ≥ 1mm (5 pts), concordant ST depression ≥ 1mm in V1-V3 (3 pts), discordant ST elevation ≥ 5mm (2 pts). ≥ 3 pts → STEMI.
Digoxin Effect vs Toxicity
Know the difference -one is expected, one is dangerous
Digoxin effect (therapeutic): "Salvador Dali moustache" -downsloping ST depression with scooped/sagging morphology. Shortened QT. This is expected and NOT toxic.
Digoxin toxicity:
• Virtually ANY arrhythmia (classic: regularised Afib, bidirectional VT, accelerated junctional rhythm, PAT with block)
• Nausea, vomiting, visual disturbances (yellow halos)
• Risk factors: hypoK, hypoMg, renal failure, advanced age
Action for toxicity: Hold digoxin. Check level + K⁺ + Mg²⁺. Digoxin-specific antibody (Digibind/DigiFab) if hemodynamically unstable, life-threatening arrhythmia, or K⁺ > 5.0.
Hypothermia (Osborn/J Waves)
Pathognomonic for hypothermia
Pattern: Positive deflection at the J-point (junction of QRS and ST segment). Amplitude increases as temperature drops.
Key: At core temp < 28°C → high risk of VF. Osborn waves resolve with rewarming. NOT an indication for antiarrhythmics.
Action: Rewarm. See Hypothermia topic. "No one is dead until warm and dead."
📐 Quick Reference -Intervals & Axes
Parameter
Normal
Abnormal
Think...
Heart Rate
60-100 bpm
< 60 = bradycardia, > 100 = tachycardia
300 / (# large boxes between R-R)
PR Interval
120-200 ms
> 200 = 1st degree AV block. Short PR = WPW or junctional
3-5 small boxes
QRS Duration
< 120 ms
> 120 = BBB, ventricular rhythm, hyperK, or pre-excitation
< 3 small boxes
QTc
< 440 (M) / < 460 (F)
> 500 = high Torsades risk
QTc = QT / √RR. Use calc.
Axis
-30° to +90°
Left axis: -30° to -90° (LVH, LAFB). Right axis: +90° to +180° (RVH, PE, LPFB)
Lead I and aVF both upright = normal
ECG Systematic Approach: Rate → Rhythm → Axis → Intervals (PR, QRS, QT) → ST segment/T waves → Compare to prior. Never skip steps -pattern recognition fails when you're tired. Systematic review catches what your eyes miss.
Quick Reference
🧪 Lab Interpretation Guide
Comprehensive quick reference for common lab abnormalities, workup algorithms, and interpretation pearls. Organized by lab category for rapid bedside use.
Check PaCO2: if same direction as pH → respiratory cause
3
Check HCO3: if opposite direction as pH → metabolic cause
4
Check compensation (Winter’s formula for metabolic acidosis: expected PaCO2 = 1.5 × HCO3 + 8 ± 2)
5
If metabolic acidosis: check anion gap (Na − Cl − HCO3, normal 12 ± 2)
6
If AG elevated: check delta-delta ratio (ΔAG / ΔHCO3). >2 = concurrent metabolic alkalosis. <1 = concurrent NAGMA* *NAGMA = Non-Anion Gap Metabolic Acidosis
AG Metabolic Acidosis (MUDPILES):M ethanol · U remia · D KA · P ropylene glycol · I soniazid/Iron · L actic acidosis · E thylene glycol · S alicylates
Non-AG Metabolic Acidosis (HARDUP):H yperalimentation, A ddison’s, R TA, D iarrhea, U reteral diversion, P ancreatic fistula
Learning Library
🎬 Media Library
Movies, documentaries, TV series, and books for medical professionals. Unwind after a shift or level up your financial literacy.
📚 Medical Finance Books
Why this matters: Medical school doesn't teach personal finance, but the decisions you make during residency -student loan strategy, disability insurance, retirement accounts -can mean hundreds of thousands of dollars over your career.
The White Coat Investor
James Dahle, MD
The bible of physician finance. Student loans, investing, insurance, retirement, and tax strategies. Start here.
Financial Residency
Ryan Inman
Written for residents. Budgeting on a resident salary, PSLF vs refinance, building a foundation early.
The Physician Philosopher's Guide
Jimmy Turner, MD
Finance meets burnout and intentional living. The "why" behind financial independence.
The Psychology of Money
Morgan Housel
Behavior -not knowledge -drives financial outcomes. Short chapters, easy read on call.
I Will Teach You to Be Rich
Ramit Sethi
6-week program to automate your finances. Simple system for people who don't want to think about money.
The Millionaire Next Door
Thomas Stanley
High income doesn't equal wealth -spending habits do. A reality check for future attendings.
Die with Zero
Bill Perkins
Challenges "save everything." Optimize life experiences, not just net worth.
Rich Dad Poor Dad
Robert Kiyosaki
Assets vs liabilities and financial literacy. Simple concepts med school never covers.
🎬 Movies
Patch Adams
1998 · Comedy Drama
Robin Williams as a med student who believes humor and compassion are the best medicine
Awakenings
1990 · Drama
Robin Williams and Robert De Niro -a neurologist discovers L-DOPA's effects on catatonic patients
The Doctor
1991 · Drama
A surgeon becomes a patient and learns empathy. Required viewing for bedside manner
Wit
2001 · Drama
Emma Thompson as a professor with ovarian cancer. Devastating portrayal of the patient experience
Something the Lord Made
2004 · True Story
First blue baby operation -Vivien Thomas and Alfred Blalock at Johns Hopkins
Philadelphia
1993 · Drama
Tom Hanks as a lawyer with AIDS fighting discrimination. Landmark film for HIV awareness
Lorenzo's Oil
1992 · True Story
Parents of a boy with ALD develop an experimental treatment. The power of patient advocacy
Gifted Hands: The Ben Carson Story
2009 · True Story
Cuba Gooding Jr. as neurosurgeon Ben Carson -from struggling student to pioneering the first successful separation of conjoined twins joined at the head
📽️ Documentaries
Extremis
2016 · Netflix
ICU end-of-life decisions filmed in real time. Essential for goals-of-care conversations
Bleeding Edge
2018 · Netflix
Medical device industry and patient safety. Eye-opening
Lenox Hill
2020 · Netflix
Docuseries following 4 physicians at Lenox Hill Hospital in NYC
The Surgeon's Cut
2020 · Netflix
4 pioneering surgeons share their personal stories and groundbreaking procedures
The First Year
2001 · Documentary
Follows 7 interns through their first year of residency. Raw and real
📺 TV Series
Scrubs
2001–2010 · Comedy
The most accurate portrayal of residency culture. Comedy with surprisingly emotional depth
House MD
2004–2012 · Drama
Diagnostic reasoning at its best (and most dramatic). Great for clinical thinking
ER
1994–2009 · Drama
The gold standard for medical drama. More realistic than most modern shows
The Pitt
2025 · Drama
Noah Wyle returns to the ER. Real-time 15-hour shift in a Pittsburgh trauma center. The most realistic medical show since ER
Learning Library
🎙️ Channels & Podcasts
Curated medical education YouTube channels, podcasts, and websites. The best free resources for residents and medical students.
The clinical decision support standard. Usually institutional access
💡 Tip: Most residency programs provide free access to UpToDate, DynaMed, and AMBOSS. Check with your program coordinator. For everything else on this list -it's all free.
Learning Library
🔗 Resources
Essential medical education resources -guidelines, references, and tools every resident should bookmark.
📚 Recommended Books
Oxford Handbook of Clinical Medicine
Ian B. Wilkinson et al.
The classic pocket reference for medical students and junior doctors. Covers all major clinical topics in a concise, practical format
Guide to the Most Common Internal Medicine Workups and Diseases
Mitchell Edwards, D.O.
Evidence-based guide to common hospital-based workups and diseases seen in internal medicine. Perfect for residents and students on IM rotations
Marino's The ICU Book
Paul L. Marino, MD PhD FCCM
The gold standard ICU reference. Covers ventilators, hemodynamics, sepsis, nutrition, and every critical care topic in a clear, practical style
Harrison's Principles of Internal Medicine
Longo, Fauci, Kasper et al. · 22nd Edition
The definitive internal medicine textbook. Comprehensive pathophysiology, diagnosis, and management across every specialty
Pocket Medicine
Marc S. Sabatine · 9th Edition
The Massachusetts General Hospital handbook of internal medicine. Concise, high-yield reference that fits in your white coat pocket
Search the medical literature. Free access to abstracts and many full-text articles
💡 Tip: Most residency programs provide free access to UpToDate, DynaMed, Micromedex, and VisualDx. Check with your program coordinator -don't pay for something your institution already covers.
Tools190 One-PagersPrint-Ready PDF
Infographic Library
190 single-page visual summaries built for the bedside, one per high-yield topic. Every card opens a print-ready PDF sized for A4, so you can pin it in the workroom or keep it on your phone. Each one is also embedded in its parent topic under the One Pager tab.
📊 All Infographics
How to use these: tap any card to open the full-size PDF. The thumbnail is a preview only, the PDF is vector and stays sharp when you zoom or print. Sorted by series number within each category.
🔍
No infographics match that search. Try a topic name (sepsis), a category (renal), or a series number (23).
Know why, not just what. The why behind every decision.
What is RoundsRx?
RoundsRx was built on a simple idea: residents should not just memorize what to do, they should understand why they are doing it. Every protocol, every drug choice, every clinical decision is grounded in the landmark trials and current guidelines that shaped it. When you understand the why, you stop cramming and start thinking like a physician.
It covers 249 clinical topics and tools across 15 rotations, from ICU protocols and cardiology to nephrology, heme/onc, and palliative care. Each topic is built around how residents actually work: pimp questions for rounds prep, clinical case scenarios, drug tables with brand names and dosing, trial citations with hover descriptions, and "updated practice" flags that highlight where old teaching has been overturned by new evidence.
Beyond clinical content, RoundsRx includes a media library with medical movies, documentaries, TV series, and recommended books for residents, plus a curated resources page with clinical guidelines, tools, and textbook recommendations, because residency is more than just medicine.
Build Stats
232
Clinical Topics & Tools
6,179
Drug Table Entries
1,070
Pimp Questions
15
Rotation Pages
1,803
Trial Citations
1,165
Clinical Alert Flags
28
Calculators
569
Clinical Scenarios
729
Clinical Pearls
190
Infographics
Key Features
🔍 Smart Search
Full-text search across every word on the site, all topics, drugs, and 1,808 trial citations. Results highlight and scroll directly to the matching content.
📚 Trial Citations
1,808 trial badges with hover tooltips explaining study design, key findings, and clinical impact.
🧠 Pimp Me Quiz
1,070 attending-style questions with reveal answers -including SSC 2026 and 2026 ACC/AHA Dyslipidemia guideline updates. Filter by rotation or topic. Perfect for pre-rounds prep.
🔄 Updated Practice
1,178 clinical alert flags highlighting key warnings, updated practice, and evidence-based practice changes.
📋 Clinical Cases
34 step-by-step bedside scenarios with timelines, drug choices, and teaching points at each decision point.
🌙 Dark Mode + Offline
Full dark mode support. Works offline in the hospital -no WiFi needed.
🧮 28 Calculators
Organized by rotation -Nephrology, Cardiology, Pulmonology, ICU, GI, General. CrCl, MELD, CHA₂DS₂-VASc, PREVENT (2026), ASCVD Pooled Cohort, Wells, NEWS/MEWS, and more.
🖨️ Print-Ready
Every topic has a one-pager designed for printing. QR poster for resident lounges. Optimized print styles.
This application, including all clinical content, source code, design, and underlying data structures, is the proprietary intellectual property of RoundsRx. Unauthorized copying, redistribution, modification, reverse engineering, or creation of derivative works is strictly prohibited.
You are granted a personal, non-transferable, non-exclusive license to use RoundsRx for your own clinical education and patient care. Commercial use, resale, or republishing of any part of this application requires written permission from RoundsRx.
Changelog
v5.7 - August 12, 2026
Internal files were publicly readable, and the rule meant to block them had never worked. A post-deploy check found /CLAUDE.md returning 200 with its full contents, and every infographic HTML source under /infographics/_src/ being served the same way, even though a forced 404 redirect for that exact path had been sitting in the Netlify config. The reason is an ordering rule that is easy to get wrong: edge functions run before the redirect engine. The Open Graph edge function matches every path, and the call it makes to fetch the page reads the static file directly, so the redirect was never reached on any URL. Blocking is now done inside that edge function, ahead of its static-asset shortcut so that source images cannot slip through on their file extension, and the config rules were kept as a fallback in case the edge function is ever removed. The PDFs, thumbnails and everything else under /infographics/ stay public, since those are the product. The .git and .claude folders were checked and are not served at all.
Every clinical pearl now has a permanent number. All 729 pearls carry a fixed number from #1 to #729, shown on the library card and on Pearl of the Day, so one can be found again or quoted to a colleague instead of being re-hunted by wording. The cards did already show a number, but it was not a real identifier: it counted position within whatever was currently on screen, so the same pearl was #1 under Cardiology and a different number after a search, and two pearls could both show #1 at once. The number now comes from the master list and never moves, whichever rotation filter or search is active. Searching a number jumps straight to it: type 412 or #412 in the pearls search box. That search deliberately still runs as ordinary text as well, because 71 pearls contain "50" and treating the query as a number alone would have quietly hidden every 50 mg dosing pearl from someone who just wanted dosing. So a number search adds a result, it never removes one.
"Submassive" and "massive" PE retired across the site, and a trial claim corrected. The 2026 AHA/ACC guideline replaced the old massive / submassive / low-risk vocabulary with Clinical Categories A to E, and while the PE one-pager and the top of the PE page had already been rebuilt around the new scheme, the body text of 15 views had not, so a reader could meet both vocabularies in the same session. Every clinical statement now uses the new categories: Category E where the patient has cardiopulmonary failure, C3 to D for RV strain with elevated biomarkers, and C2 where only one of the two is abnormal. Outside the PE topic, where there is no category legend on the page, the old word is kept in brackets so the sentence still reads. Three kinds of mention were deliberately left alone: the old-to-new mapping table, headings that read "formerly massive", and the trial tooltips, since PEITHO, ULTIMA, SEATTLE II, FLARE and FLAME each enrolled by the old definitions and rewriting their criteria would misreport what was actually studied. Searching "submassive" still finds the page, because the mapping keeps the word. Separately, a clinical pearl was wrong and has been rewritten: it credited MOPETT with "less bleeding than full-dose" lysis, but MOPETT had no full-dose arm. It compared half-dose alteplase against anticoagulation alone in 121 patients and no bleeding occurred in either group, so that comparison was never made. The pearl now gives the real comparator and the real result (pulmonary hypertension 16% vs 57% at 2.3 years, no mortality benefit, single center).
Site-wide topic count corrected, and one place that still had the old number. The description shown to search engines and social previews claimed 250 evidence-based protocols in seven places while the site actually has 249, and the search keywords line still read "240+ protocols", a number a previous cycle recorded as having been corrected everywhere. All eight now read 249, matching the sitemap exactly. Historical changelog entries were deliberately left alone, since those describe what was true at the time and rewriting them would erase the record. Every other published figure was recounted from the page source and confirmed unchanged: 231 topics and tools, 15 rotations, 1,070 pimp questions, 1,803 trial citations, 1,165 alert flags, 569 clinical scenarios, 729 pearls and 189 infographics. The one that had drifted was drug-table entries, corrected from 6,192 to 6,179 across 1,103 tables, the small reduction left by removing the Quick Reference tabs.
The app now opens instantly on repeat visits, and pages reached from Google stop reloading on every click. Two things were slowing the site down. The offline system was set to always wait for a fresh download before showing anything, so the stored copy was never used for speed, only for being offline: every visit, even by someone who had been reading an hour earlier, sat waiting on the network first. Worse, the change that gave each topic its own indexable page means a page opened from a search result contains only that one topic, so clicking through to any other topic forced a complete page reload, measured at up to 3.7 seconds each time. Someone arriving from Google was effectively getting a brand new page load for every topic they opened. The site now keeps a complete copy of itself and serves that, so it appears immediately and every topic is already there to switch to, which measured at about a third of a second instead of a reload. It also means the whole reference now works with no connection at all, which matters on hospital wifi. Search engines are unaffected and still receive the one-topic-per-address version, so indexing is unchanged. Because the stored copy can be one version behind, a "an updated version is available" prompt with a Refresh button now appears whenever a new build is detected, including when you return to the tab, so a clinical correction reaches readers in seconds rather than sitting unseen.
"Print Infographic" now opens the sheet immediately instead of stalling for 2.5 seconds. The button used to load the one-pager into a hidden frame and try to print it, waiting 2.5 seconds before giving up and opening it in a new tab. Testing on the live site showed that attempt can never succeed in Chrome: it renders PDFs in an internal viewer that counts as a separate origin, so a page is not permitted to press print on a PDF it has embedded, no matter how the security settings are arranged. The result was that every click did nothing at all for two and a half seconds and then opened the tab anyway. The button now opens the sheet straight away, where the print button and Ctrl+P work normally. Being honest about it: this is one keystroke rather than a print dialog appearing by itself, which is not achievable for an embedded PDF in current browsers, and the printed result is the full-quality vector sheet rather than a downscaled image.
Infographic thumbnails moved to WebP, cutting 35 MB. All 378 preview images (a 520 px copy for the library cards and a 1040 px copy for retina screens) were JPEG at near-maximum quality, which is the worst case for dense text: re-encoding them as JPEG at a lower setting saved only about 15% and started to blur small type. WebP at the same visual quality took the set from 89.0 MB to 53.9 MB, a 39% reduction, verified by comparing text-dense crops at full magnification before and after so that subscripts like HCO₃ stay legible. Total site content is now 97.1 MB. The pixel dimensions were deliberately left alone: they match exactly what the embed and the library grid render at, so shrinking them would show as soft thumbnails on modern phones. The build script now produces WebP for any new sheet automatically.
Dashboard banners removed, Pearl of the Day promoted. The Surviving Sepsis 2026 and 2026 ACC/AHA Dyslipidemia banners had been sitting on the homepage since March, and both had outlived their news value while two newer guidelines (acute PE in March, CKM in June) never got a banner at all. Together they consumed 158 px above the fold, which was enough to push the rotation grid, the actual navigation, off the first screen. With both removed, Pearl of the Day rises from 436 px to 274 px and the first rotation card moves from 795 px to 584 px, so the grid now sits above the fold at a standard viewport height. The hero already links to current guidelines, so nothing was lost in the way of surfacing new content.
Six stale rotation topic counts corrected. The homepage rotation tiles were each under-reporting by one: ICU 26 to 27, Cardiology 25 to 26, Nephrology 14 to 15, Emergency Medicine 16 to 17, Endocrinology 17 to 18, Ambulatory 25 to 26. Four were the CKM page, which was added to those grids without its count being carried through; the ICU and Emergency Medicine tiles had drifted earlier. Every tile was then re-checked against the live number of cards in its grid, and all 14 now agree.
CKM: the COR tags now explain themselves. The page marked recommendations COR 1 and COR 2a but never said what COR meant, and those six tags were the only use of that notation on the entire site, which otherwise writes "Class I" in 91 places. A short legend now sits immediately above the first tagged table: COR is the Class of Recommendation, COR 1 means benefit far outweighs risk and is worded "is recommended", COR 2a means reasonable and worded "can be useful", COR 2b is "may be considered", and COR 3 means do not do it. It also says why the distinction earns its place on this page: annual lipids, glycemia, blood pressure and eGFR with UACR are COR 1, while pre-HF biomarker screening is only COR 2a, so the first set is expected and the second is a defensible judgment call.
Lipid infographic switched from COR to Class notation. The printed sheet used "COR 1" in three places, the only infographic in the library of 154 to use that abbreviation. A one-pager is read standalone, pinned to a wall or reached by its QR code, so it has no page around it and no room for a legend to explain an acronym. It now reads "Class 1", which is the plain-English form and matches the 91 places the rest of the site already writes "Class I". The CKM topic page deliberately keeps COR, because it now defines the term on the page and the extra precision of COR 2a versus COR 1 is doing real work there. Re-rendered at 788.8 pt, still single-page and inside the fill window, thumbnail rebuilt and QR re-verified.
NEW INFOGRAPHIC #155: CKM Syndrome, and a coverage audit that sized the real gap. An audit of all 204 clinical topic pages against the library found 146 with a printable sheet and 58 without. Fourteen of those 58 are quick-reference views that are already pocket cards in their own right (ECG interpretation, IV fluids, code blue, lab interpretation and similar) plus the library page itself, which leaves 44 genuine clinical topics with no one-pager. The audit also checked for near-duplicates before anything was written, which removed candidates that only looked like gaps: an "ACS Overview" sheet would have substantially duplicated the existing STEMI (#57) and NSTEMI (#58) sheets. Confirmed as real gaps with no overlap: obesity and GLP-1 agents (no sheet at all), outpatient diabetes (only the inpatient sheet #87 exists) and chronic thyroid disease (only the emergencies sheet #84). The first sheet of that campaign is now built: CKM Syndrome, covering the five stages with the Stage 3 criteria spelled out, screening set by stage, the four CKD drug thresholds that are easiest to confuse (RAS inhibitor at UACR 30 with eGFR 30, SGLT2i at UACR 200 with eGFR 20, the Class 2a SGLT2i band at UACR 30 to 199 without diabetes, and finerenone at UACR 30 with eGFR 25 despite the other two rather than instead of them), the type 2 diabetes routing where the trigger is cardiovascular risk rather than A1c, and the two reversals worth knowing. Rendered at 786.5 pt on the first pass, single page, QR machine-verified. Library is now 155 sheets.
NEW INFOGRAPHIC #156: Obesity Management and GLP-1 Agents, the first topic in the gap list with no sheet of any kind. Covers the three eligibility tiers (lifestyle for everyone at 5% to 10%, pharmacotherapy at BMI 30 or 27 with a comorbidity, surgery above that), full titration schedules for tirzepatide (2.5 mg weekly stepping by 2.5 to 15) and semaglutide (0.25 stepping to 2.4) with the weight loss each achieved in SURMOUNT-1 and STEP 1, and the SELECT result that makes these cardiometabolic rather than cosmetic drugs: 20% MACE reduction in 17,604 adults with established CVD and obesity but no diabetes, largely independent of how much weight was lost. Two reversals are called out because both are still widely taught the old way. The 2023 ASA advice to hold weekly GLP-1s for a week before surgery was replaced by the December 2024 multi-society guideline under which most patients continue, with individualized assessment instead of an automatic stop. And the bariatric surgery threshold moved in 2022 to BMI above 35 regardless of comorbidity, with 30 to 34.9 considered if metabolic disease is present, so quoting the NIH 1991 numbers under-refers patients who now qualify. The sheet also carries what gets skipped before a prescription is written: excluding secondary causes, swapping the obesogenic drug first (antipsychotics, insulin, glucocorticoids, mirtazapine, gabapentinoids, beta-blockers), screening the travelling comorbidities, the 12-week non-response checkpoint at under 5%, and the double-dosing trap where Wegovy and Ozempic are the same molecule under different brands and maximum doses. First render came in underfilled at 637.3 pt, which is what surfaced those omissions; final render 782.8 pt, single page, QR verified. Library is now 156 sheets.
NEW INFOGRAPHIC #157: Outpatient Type 2 Diabetes, built on the ADA Standards of Care 2026. Carries the individualized targets (A1c under 7% for most, under 8% where life expectancy is limited or hypoglycemia is a risk, because a tighter number in a frail patient causes harm rather than earning credit), blood pressure under 130/80 with systolic under 120 encouraged at high cardiovascular or kidney risk, the diagnostic thresholds and the prediabetes band, and the situations where the A1c cannot be trusted at all (hemoglobinopathy, recent transfusion or blood loss, hemolysis, iron deficiency, erythropoietin, advanced CKD, dialysis, pregnancy). The core of the sheet is that drug choice follows the comorbidity, not the A1c: GLP-1 RA or SGLT2i are started for the organ indication independent of the A1c and independent of whether the patient is on metformin, and ADA 2026 moves them earlier, considered from the point of diagnosis in high-risk patients. It also reconciles two 2026 guidelines that sound contradictory, since ADA keeps metformin first-line for glycemia while the CKM guideline calls it a Class 2a add-on after the cardioprotective agent. Both say the same thing from different starting points: the organ-protective drug is chosen for the organ and metformin is chosen for the glucose. Rounded out with the annual screening set (the UACR is the one most often skipped), insulin initiation at 10 units or 0.1 to 0.2 units/kg titrated against the fasting glucose, a CGM time-in-range target above 70% with under 4% below 70 mg/dL, and the safety items: euglycemic DKA, the expected early eGFR dip on an SGLT2i that should not trigger stopping the drug, metformin as a lactic acidosis question rather than a kidney one, and not stacking a DPP-4 inhibitor on a GLP-1. First render was underfilled at 652.3 pt, which surfaced the missing diagnostic criteria; final 797.8 pt with 16.4 pt of footer clearance. Library is now 157 sheets.
NEW INFOGRAPHICS #158 to #160: the heme malignancy cluster, which until now had only the pancytopenia sheet between three major topics. #158 Multiple Myeloma carries the IMWG requirement that both halves be present (clonal plasma cells plus a myeloma-defining event), CRAB with its numeric cutoffs, and SLiM with the explanation of why it exists: 60% plasma cells, a free light chain ratio of 100 or more, or two focal MRI lesions identify patients whose progression is near-certain, so they are treated before the kidney fails or the vertebra collapses. It also places the patient on the spectrum (MGUS versus smoldering versus active disease, with the thresholds), flags AL amyloidosis as the mimic that damages organs without meeting myeloma criteria, gives R-ISS with its survival figures, and states three workup points that are commonly wrong: order SPEP, UPEP and serum free light chains together because roughly 20% are light-chain only, the plain skeletal survey is obsolete, and bone scan is the wrong test because myeloma lesions are purely lytic. #159 Acute Leukemia leads with the instruction that matters most: if APL is possible, start ATRA on suspicion without waiting for cytogenetics, because the deaths are from coagulopathy in the first days. Then the four first-48-hour emergencies (febrile neutropenia with the 60-minute clock, tumor lysis including that rasburicase is contraindicated in G6PD deficiency and that asymptomatic hypocalcemia should not be corrected, leukostasis with the caution against transfusing red cells before cytoreduction, and DIC), differentiation syndrome with dexamethasone at first suspicion, and what treatment actually involves so the ward team can anticipate the toxicity. #160 Lymphoma covers excisional biopsy rather than FNA and why, Lugano staging, IPI, Deauville and response-adapted therapy, first-line by disease including the POLARIX result (879 patients, 5-year PFS 64.9% versus 59.1%, HR 0.77, strongest in higher IPI so a risk-directed choice rather than a blanket replacement), the aggressive-is-curable paradox, four named lymphomas with twists that cannot be guessed (Burkitt as an emergency, mantle cell, gastric MALT where eradicating H. pylori alone can cure early disease, and primary CNS lymphoma where steroids before biopsy can make the lesion vanish), and the single most consequential item: screen HBsAg and anti-HBc before rituximab, since reactivation can be fatal and is preventable. All three needed content added after underfilled first renders (569 pt for leukemia, 535.3 for lymphoma), which is again how the omissions were found. Library is now 160 sheets.
NEW INFOGRAPHICS #161 to #163, plus a duplicate avoided.#161 Amyloidosis leads with the clue that makes the diagnosis, heart failure with thick walls but low ECG voltage, then separates AL from ATTR and AA because the treatments have nothing in common, and states the sequence that must not be reversed: screen for a light chain first, prove amyloid with Congo red, then type it by mass spectrometry. A red warning box carries the error that matters most: a positive PYP scan does not diagnose ATTR on its own, because PYP can be positive in AL too, and calling ATTR on the scan alone in a patient who has AL starts the wrong treatment in the disease where delay is measured in months. Also the inverted cardiac drug rules (preload dependent, so beta-blockers and vasodilators are tolerated badly, and digoxin binds amyloid fibrils), and the point that an MGUS alongside unexplained heart failure, neuropathy or proteinuria is not incidental. #162 Hyperviscosity Syndrome is built around it being a clinical rather than laboratory diagnosis: treat on the triad and the fundus without waiting for a viscosity result. Explains why IgM causes most cases despite Waldenstrom being far rarer than myeloma (a large pentamer that stays intravascular, which is also why plasmapheresis works so well), and carries the two errors that hurt: do not transfuse red cells before pheresis, and beware the rituximab IgM flare. #163 Hypocalcemia and Hypoparathyroidism mirrors the existing hypercalcemia sheet: correct for albumin first, let PTH split the differential, then read the phosphate to split it again. The recurring theme is magnesium, which must be replaced before any hypocalcemia is called refractory, alongside why chronic hypoparathyroidism needs active vitamin D (no PTH means no 1-alpha hydroxylation) and why the calcium target is deliberately low-normal to avoid nephrocalcinosis. It is linked to both the hypocalcemia and hypoparathyroidism topics from one sheet. A fourth gap was closed without writing anything. The uncovered "hypercalcemia of malignancy" topic turned out to be fully served by the existing hypercalcemia sheet #86, which already carries the PTH split, PTHrP, calcitonin, denosumab and the granulomatous causes, so that sheet was linked to the second topic rather than a near-duplicate being authored, the same call made earlier against building an "ACS Overview" sheet on top of the existing STEMI and NSTEMI ones. Library is now 163 sheets.
NEW INFOGRAPHICS #164 to #167: the rheumatology cluster, which had sheets for lupus, ANCA vasculitis, gout, antiphospholipid syndrome and GCA/PMR but nothing for four common topics. #164 Rheumatoid Arthritis is built on the ACR 2021 guideline: methotrexate as the anchor drug, treat-to-target with a named score, steroids as a bridge only, and the four drug classes with what each one costs you (tocilizumab normalizes the CRP so it can no longer detect infection; JAK inhibitors carry the class boxed warning after a safety trial found more cardiovascular events and malignancies against a TNF inhibitor in patients over 50 with a risk factor). It carries the pre-biologic checklist that prevents disasters, and three pearls that matter on the ward: never combine methotrexate with trimethoprim-sulfamethoxazole (both antifolates, severe pancytopenia), leflunomide needs a cholestyramine washout, and ask about the neck before any intubation, because atlantoaxial subluxation in longstanding disease can compress the cord on extension. #165 Scleroderma Renal Crisis is organized around one instruction: start captopril and do not stop it when the creatinine rises, because stopping converts a recoverable crisis into permanent dialysis. It flags that glucocorticoids are the classic trigger, that around 10% are normotensive, that the microangiopathy mimics TTP but is treated with an ACE inhibitor rather than plasma exchange, and that ARBs are not a substitute. It also carries the counterintuitive prophylaxis paradox: ACE inhibitors treat the crisis but prior ACE inhibitor use has been associated with a higher risk of developing it, so they should not be prescribed preventively. #166 Dermatomyositis and Polymyositis is built around the antibody deciding the plan: anti-synthetase and anti-MDA5 for lung disease (MDA5 with rapidly progressive ILD and often a normal CK, so a normal CK must not reassure), anti-TIF1-gamma and anti-NXP2 for malignancy, and anti-HMGCR statin-associated necrotizing myopathy, which does not resolve on stopping the statin and needs immunosuppression. A red box states that adult dermatomyositis is paraneoplastic until proven otherwise and that a negative initial cancer search does not close the question. #167 Seronegative Spondyloarthropathies covers inflammatory back pain (pain that improves with exercise and not with rest being the most discriminating feature), MRI of the sacroiliac joints detecting sacroiliitis years before plain films, and the two treatment points that separate it from rheumatoid arthritis: methotrexate and sulfasalazine do not work for axial disease, and the comorbidity picks the biologic, because IL-17 inhibitors can trigger or worsen inflammatory bowel disease. Library is now 167 sheets.
CLINICAL CORRECTION: obeticholic acid was removed from the site, because it no longer exists in the US. While verifying content for a new PBC sheet, a check of current second-line therapy found that Ocaliva (obeticholic acid) was withdrawn from the US market at FDA request over a risk of serious liver injury, including in patients without cirrhosis, with the transition period ending in November 2025 and the approval formally withdrawn. The site was still recommending it in 8 places across the PBC and PSC topic: a treatment bullet, a drug-table row with dosing, a management list, a summary tile, a One Pager step, a One Pager drug row, a "do not do" item and a referral criterion. All now name the current second-line agents, elafibranor (Iqirvo) 80 mg daily and seladelpar (Livdelzi) 10 mg daily, both PPAR agonists given with UDCA or alone if UDCA is not tolerated, and each carries an explicit note that obeticholic acid was withdrawn and should not be prescribed. The historical POISE trial citations were left intact, since they accurately describe what that trial showed. This is the exact failure mode the guideline surveillance rule exists to catch: nothing was broken, the audit stayed green, and the page would have kept telling residents to prescribe a drug that had been pulled from the market.
NEW INFOGRAPHICS #168 to #170.#168 PBC and PSC separates two cholestatic diseases that behave nothing alike: PBC has AMA, small intrahepatic ducts and genuinely effective therapy, while PSC has a beaded MRCP, an inflammatory bowel disease association that warrants colonoscopy even without symptoms, and no medical therapy that alters the disease, with high-dose UDCA actively harmful. It carries the corrected PBC ladder above, the rule that a dominant stricture needs tissue before dilating because cholangiocarcinoma hides there, and a mimics table led by IgG4-related sclerosing cholangitis, which looks like PSC but responds dramatically to steroids, so IgG4 should be checked in every new PSC. #169 Pheochromocytoma and Paraganglioma enforces the order that keeps patients alive: metanephrines drawn supine before imaging, imaging before surgery, and alpha blockade for 7 to 14 days before any beta blocker, since a beta blocker first leaves alpha-mediated vasoconstriction unopposed. It also covers the interfering drugs that cause false positives, that around 40% are hereditary so everyone is referred for genetic testing, the post-operative hypotension and hypoglycemia to expect, and a spell differential led by panic disorder, since most patients tested do not have the tumor. #170 Autoimmune Hepatitis covers the composite diagnosis, why antibody titers should not be followed while IgG should, treating for at least 2 to 3 years because relapse after withdrawal is common, and a dedicated section on acute severe disease, where antibodies may be negative, steroids should be started promptly, and the transplant center is contacted in parallel rather than after steroids fail. Library is now 170 sheets.
NEW INFOGRAPHICS #171 to #173: the infectious disease cluster.#171 Syphilis is organized around the fact that the stage sets the dose: a single 2.4 million unit dose of benzathine penicillin G for primary, secondary and early latent disease, but three weekly doses for late latent or unknown duration, which is the commonest real-world situation. It flags that neurosyphilis is not a late stage and that ocular or auditory symptoms at any stage are treated as neurosyphilis without waiting for a lumbar puncture, carries the prozone phenomenon in which a very high titer makes the RPR read falsely negative precisely in secondary syphilis and pregnancy, and defines cure numerically as a fourfold fall in RPR at 6 and 12 months. Pregnancy gets its own section, since penicillin is the only regimen that prevents congenital syphilis and allergic patients must be desensitized rather than switched to doxycycline, with maternal treatment needing to be at least 30 days before delivery. Prevention now includes doxy-PEP per the CDC 2024 guidance: 200 mg of doxycycline within 72 hours after sex for men who have sex with men and transgender women with a bacterial STI in the past year, which cut syphilis and chlamydia by over 70%. #172 Herpes Simplex leads with a red box instructing that suspected HSV encephalitis is treated with IV acyclovir immediately, without waiting for PCR, MRI or lumbar puncture, and notes that an early negative CSF PCR does not exclude it. It sets out that PCR is the test while the Tzanck smear is obsolete and IgM unreliable, gives the first-episode, recurrent and suppression regimens separately, explains why episodic treatment must be patient-initiated within the prodrome to work at all, and adds a genital ulcer differential where painful and multiple points to HSV while painless and indurated points to syphilis. #173 Herpes Zoster covers the 72-hour antiviral window, the honest caveat that antivirals do not reliably prevent postherpetic neuralgia, and the two sites needing same-day specialists: ophthalmicus with the Hutchinson sign, and Ramsay Hunt, which is missed whenever a facial palsy is diagnosed without looking in the ear and which recovers worse than Bell palsy. Also zoster sine herpete, sacral zoster causing urinary retention, that exposure risks varicella in the contact rather than zoster, and the two-dose non-live recombinant vaccine for everyone from 50, or from 19 if immunocompromised. Library is now 173 sheets.
NEW INFOGRAPHICS #174 to #177: the multisystem cluster.#174 Sarcoidosis makes the point that the Scadding stage describes the radiograph and does not tell you to treat: the threshold is significant symptom burden or organ dysfunction, so an asymptomatic Stage II patient is observed while a Stage I patient with cardiac involvement is treated urgently. It flags Lofgren syndrome, where roughly 90% remit spontaneously and steroids are not indicated, the organs that are treated regardless of symptoms (cardiac, neurologic, ocular, severe hypercalcemia), and two errors: serum ACE is not a diagnostic test, and every biopsy needs mycobacterial and fungal culture, because starting steroids in undiagnosed tuberculosis is the trap this diagnosis invites. #175 PRES is built around the name being misleading on both counts, since it is neither always posterior nor always reversible. Covers why the rate of blood pressure rise matters more than the number and that 20% to 30% are normotensive, the ADC and diffusion findings that separate vasogenic edema from an infarct, that calcineurin inhibitors cause it at therapeutic levels so a normal level is no reassurance, and a mimics table led by stroke and RCVS, where getting it wrong cuts both ways since thrombolysis in PRES is harmful. #176 Calciphylaxis leads with the fact that pain out of proportion precedes any visible lesion, then reads as a list of things to stop today: warfarin above all, since it blocks matrix Gla protein and directly drives vascular calcification, plus calcium binders and active vitamin D. Sodium thiosulfate is presented honestly as widely used and biologically plausible but supported by observational rather than randomized evidence, and the sheet states the roughly 50% one-year mortality with sepsis as the usual cause of death, arguing for palliative input alongside active treatment rather than after it. #177 Renal Transplant Medicine opens with two overriding rules for the on-call team: never stop immunosuppression without the transplant center, and check every new drug for a calcineurin interaction. It gives the infection timeline that narrows the differential faster than anything else, and works the rising creatinine in order, including the counterintuitive point that BK nephropathy is treated by REDUCING immunosuppression while rejection is treated by increasing it, and the two can look identical on creatinine alone, which is exactly why the biopsy matters. Library is now 177 sheets.
NEW INFOGRAPHICS #178 to #181, plus three gaps closed with no new content at all. Before writing anything, the existing palliative sheets were read in full rather than searched, which showed that #116 goals-of-care already covers the family meeting comprehensively (SPIKES, REMAP, NURSE, surrogate and substituted judgment) and #117 hospice already carries the prognostication content (the surprise question, ECOG, FAST, disease-specific criteria). Both were relinked to those topics instead of near-duplicates being authored, and the lipid sheet #154 was relinked to the dyslipidemia guideline page it was built from. A fourth apparent gap, hypoparathyroidism, turned out to be already served by #163. #178 Opioid Rotation and Conversion is built around the step that is skipped: convert to oral morphine equivalents, then reduce by 25% to 50% for incomplete cross-tolerance, since tolerance to one opioid does not transfer fully to another and omitting this is the classic cause of iatrogenic overdose. It states honestly that equianalgesic tables are approximations that disagree with each other and were derived from single-dose studies in opioid-naive people, so the local table should be used and any conversion treated as a starting estimate. Breakthrough is 10% to 20% of the daily total, and methadone is flagged as non-linear and specialist-only. #179 Code Status and Advance Directives separates the documents that are wishes from the ones that are orders, and leads on the misunderstanding that matters most: DNR applies only to cardiac arrest and does not mean do not treat, with the reminder that a DNR is not automatically suspended for surgery and that deactivating an ICD is a separate order. #180 Non-Opioid Symptom Management organizes nausea by receptor rather than by habit, since the commonest reason an antiemetic fails is that it was aimed at the wrong pathway, and covers breathlessness (low-dose opioid first-line, a fan to the face, oxygen only if hypoxic), delirium, secretions and the less common symptoms. #181 Palliative Extubation states the governing principle explicitly, that an intervention no longer meeting the goals is being withdrawn rather than care, and that doses adequate to relieve observed distress are appropriate even if they may hasten death as a foreseen but unintended effect. It carries the absolute rule that no patient is extubated while any neuromuscular blockade remains, that titration follows observed distress rather than blood pressure or saturation, and that under-treatment is far more common than over-treatment. Library is now 181 sheets.
NEW INFOGRAPHICS #182 to #185, and both cardiology gaps closed without writing anything. Reading #63 valvular-heart-disease end to end showed it already covers aortic stenosis with the full TAVR versus SAVR age and life-expectancy decision, and mitral regurgitation split into primary and secondary with the operative thresholds, so it was relinked to both topics rather than two near-duplicate sheets being authored. That is the fifth and sixth gap closed this way. #182 Preventive Care and Screening is organized around the fact that the retired numbers are the ones still quoted: colorectal now starts at 45, breast is biennial from 40 to 74 after the 2024 update rather than from 50, cervical is HPV primary screening every 5 years from 30 to 65 now including self-collection, and lung screening starts at 50 with a 20 pack-year history rather than 55 and 30. It also explains that USPSTF grades are instructions, since a Grade D such as PSA at 70 and over means do not screen rather than discuss, and adds the adult immunization schedule. Worth recording how this one was verified: the first search returned breast screening as 50 to 74, the pre-2024 recommendation, and only a second targeted search confirmed the current 40 to 74. Screening ages are exactly the content where a stale search result reads as authoritative. #183 Cushing's Syndrome puts exogenous glucocorticoids as step zero, since they are by far the commonest cause and working one up as a tumor is the classic wasted month, then requires two concordant confirmatory tests before ACTH is measured, flags pseudo-Cushing explicitly, and notes that inferior petrosal sinus sampling is needed more often than expected because pituitary microadenomas are frequently invisible while incidental pituitary lesions are common. It also calls out the markedly raised VTE risk, which is the complication most often overlooked perioperatively. #184 Falls Risk and Prevention screens with three questions, and is honest about what works: exercise is the strongest single intervention and the medication review is the highest-yield thing you personally control, while vitamin D is not recommended for fall prevention in community-dwelling adults and bed alarms have not been shown to reduce inpatient falls, with restraints causing harm. It also states that "mechanical fall" is not a diagnosis but a phrase that ends the thinking. #185 Smoking Cessation leads on combining pharmacotherapy with behavioral support, notes the varenicline neuropsychiatric boxed warning was removed so it should not be withheld on that basis, covers combination NRT and the technique errors that make it fail, and includes the interaction most often missed: quitting raises levels of CYP1A2 substrates including clozapine, olanzapine and theophylline, because it is the smoke rather than the nicotine that induces the enzyme. Library is now 185 sheets.
NEW INFOGRAPHICS #186 and #187, closing four more gaps.#186 Rare and Imported Infections deliberately replaces what would have been three thin sheets. Hantavirus, Ebola and cyclosporiasis are individually too narrow to justify a printed page for a US internal medicine audience, so one sheet covers the part that is actually actionable: the exposure history, isolation, and the phone call. It opens with the rule that malaria must be excluded before anything else in a febrile returned traveler, since it kills within days while the interesting diagnoses are being considered, and a single negative smear does not exclude it. Each of the three then carries the one fact that changes management: only Andes virus transmits person to person, so North American hantavirus cases do not need isolation; Ebola patients are not contagious until symptomatic and the health department call comes before the workup; and routine ova and parasite testing does not detect Cyclospora, which must be specifically requested and may need several specimens, then treated with TMP-SMX. Also the reminder to warn the laboratory before sending specimens that cause laboratory-acquired infection, and to screen for strongyloides before any steroid. #187 Discharge Planning treats discharge as a handoff rather than an event: medication reconciliation drug by drug with the reason for every change, follow-up that exists rather than an instruction to arrange it, a named owner for every pending result, teach-back to confirm the plan landed, and the practical barriers (cost, transport, dexterity, home safety) that are almost never medical and take days to solve, which is why planning starts on day one. It is honest that not all readmissions are preventable, and that for advanced illness the right plan may be a goals-of-care conversation rather than tighter follow-up. Library is now 187 sheets.
NEW INFOGRAPHICS #188 and #189, the thyroid pair, written to a deliberately limited scope. These two were held back for several cycles because the ATA 2026 guideline on thyroid disease in preconception, pregnancy and postpartum replaced the 2017 guideline, and the full text was not available to verify against. They are now published covering non-pregnant adults only, with an explicit scope note directing pregnancy and postpartum management to the 2026 guideline rather than extrapolating from the sheet. #188 Hypothyroidism leads with two things to settle before prescribing: treat adrenal insufficiency first, since levothyroxine raises cortisol clearance and can precipitate an adrenal crisis, and do not diagnose from tests taken during acute illness. It gives the 1.6 microgram/kg replacement dose with the reasons to start low, the absorption rules that explain most treatment failures, the 6 to 8 week recheck interval and why checking earlier gives a wrong answer, the point that central hypothyroidism cannot be monitored with TSH at all, and an honest treatment of subclinical disease including stopping a trial that does not help rather than escalating it. #189 Hyperthyroidism and Graves' Disease is built around establishing the cause first, because thyroiditis must not be treated with antithyroid drugs: the gland is leaking stored hormone rather than overproducing, so a thionamide does nothing. It covers the three definitive treatment options with the factors that choose between them, the agranulocytosis and hepatotoxicity counseling that matters more than any monitoring schedule, and the commonest monitoring error in the disease, which is that TSH stays suppressed for months and titration must follow free T4 and T3. The same review found a stale citation already published. The hypothyroidism topic page carried trimester-specific TSH targets explicitly attributed to the 2017 ATA guideline, in five places including a worked clinical case. Those numbers could not be corrected without the 2026 full text, so an amber alert now marks the pregnancy guidance on that page as predating the current guideline and directs readers to check it, which removes the false appearance of currency without asserting numbers that have not been verified. Library is now 189 sheets, and every clinical topic page that warrants a printable one-pager has one.
Deploy check caught a wrong trial year that was live on the site. The pre-deploy RCT_DB step compares the trial database against the last commit, which showed the CONFIRM key had been corrected to CONFIRM_2021 while the visible trial card still read "2024 · NEJM", as did one inline citation. Verified against the primary publication: CONFIRM was published in NEJM on 4 March 2021 (Wong et al., N=300, HRS-AKI reversal 32% vs 17%). Both display instances corrected to 2021. The same check confirmed the other six RCT_DB key removals this cycle were duplicate cleanups, not data loss: each removed key (ISIS_2_1988, MADIT_II_2002, PARADIGM_HF_2014, PROVE_IT_2004, Girard_ABC_2008, HI_PEITHO_2026_DB) still exists under its dash-form equivalent, and there are zero dangling references to any removed key, so no tooltip is broken.
The "Quick Reference" tab was removed from all 19 topics that still had one. These were a legacy third summary layer, superseded twice over: every one of those topics already has both a Summary tab and a One Pager tab carrying the real printable infographic. Most of their content was template filler of exactly the kind the audit was built to catch, lines such as "Diagnose: see Overview tab for criteria" and "Treat: evidence-based algorithm, see Management tab", and each card also instructed the reader to press Ctrl+P to print the page, which the new print button has made wrong. 19 section-anchors and 18 tab buttons were removed, about 31,000 characters of markup; the count differs because one section had no button at all and was already unreachable. Before deleting, every affected topic was checked to confirm it kept another summary surface, and all 19 did. Removal used depth-aware boundaries with a div-balance assertion rather than naive slicing, and the result is confirmed by the audit: DOM parity fell by exactly 19, from 1427 to 1408, with no orphan tabs, meaning no tab now points at a section that no longer exists. Deliberately untouched: the qr-* pocket-card guides whose category label reads "Quick Reference", the "Quick Reference Card" headings inside One Pager sections, and content headings such as "Murmur Quick Reference", none of which are topic tabs.
Every print button now prints the one-page infographic instead of the protocol page. There were two button classes and both were converted: 225 print-btn in the topic hero and 97 op-print-btn inside the One Pager sections, 322 in total across all 204 clinical topic views. The new printOnePager() reads the current view, looks it up in a generated IG_PDF map, then loads that sheet into a hidden iframe and calls print on it, so the dialog opens on the one-pager itself. The old behavior printed the whole topic page, which for most topics runs to many browser-rendered pages; the sheets exist precisely so a resident can carry one. Because not every browser lets a script drive an embedded PDF viewer, a short timer opens the sheet in a new tab if printing did not fire, and navigates to it if the popup is blocked, so the button never does nothing. All 197 map entries were verified to point at a PDF that exists on disk, including topics served by a shared sheet, so aortic stenosis and mitral regurgitation both reach the valvular sheet and the three rare infections reach the combined one. The 13 views without a sheet keep the old behavior deliberately (the qr-* pocket cards and the library are already printable pages), as does the QR poster, where the poster is the page. The map is generated, not hand-maintained:gen-qr.py now rebuilds IG_PDF from the manifest alongside IG_GO, so adding a sheet and re-running it keeps the buttons current. The visible labels were changed too, which the first pass missed: the button read "Print Protocol" on 134 topics and plain "Print" elsewhere, so the behavior had changed while the wording still promised the old thing. All 309 buttons now read "Print Infographic", keeping their existing printer icon. The 13 views with no sheet were deliberately left reading "Print", since those fall back to printing the page and labelling them "Print Infographic" would be a promise the button cannot keep. The sheet opens in a new tab only. The first build fell back to navigating the current tab when the browser refused a popup, which under local file mode happened every time and took the reader off the app. It now opens via a synthetic anchor click, which inherits the button's user gesture and is not popup-blocked, and the same-tab path was removed entirely: navigating away unloads the single-page app, so going Back would mean a full reload of a very large document and losing your place in the topic.
COPD exacerbation: the 6 P’s reconciled, because the page carried THREE different versions. Adding a mimics list surfaced that copd-exacerbation-management already defined "the 6 P’s" twice more, with different members each time: a triggers table (pneumonia, PE, pneumothorax, pleural effusion, poor compliance, pollution) and a summary tile (pneumonia, pollution, PE, pneumothorax, pump failure, pills). Three lists under one name, on one page, for one disease. The deeper problem was that the triggers list was not a list of triggers. A pulmonary embolism, pneumothorax or effusion does not set off an exacerbation, it is the diagnosis instead of it, so four of those six were mislabeled. Resolution: the page now has exactly one 6 P’s, the alternative diagnoses, being PE, Pneumonia, Pneumothorax, Pump failure, Pulse (ACS or arrhythmia) and Plug or aspiration. The former triggers table is retitled Common Precipitants, keeps its content, and gains a column stating for each entry whether it is a precipitant, the diagnosis itself, or both, since an airway infection precipitates a true exacerbation while an infiltrate means pneumonia rather than AECOPD. The summary tile and the rounds checklist item that called PE a trigger were corrected to match, and sheet #38 was rebuilt on the same six, gaining the previously missing Plug and aspiration entry. PE leads the list as the highest-yield miss: roughly 1 in 6 hospitalized patients with an unexplained exacerbation, pooled 16.1%, with 68% of those emboli in main, lobar or interlobar arteries, so it is not subsegmental noise Aleva, Chest 2017.
audit.js US-English check extended, and it immediately found more. Three spellings the check did not know were added: the British forms of pheochromocytoma, aluminum and counseling. On the first run the new terms flagged the British form of counseling in four places across index.html and two other sheets that had been there all along, all now corrected. Two implementation notes worth keeping: the terms must be added in the existing [/regex/i, replacement] array form rather than as objects, and the word-boundary escapes must survive being written to the file, since a first attempt wrote literal backspace characters instead of , which would have produced regexes that silently never matched. The new terms were validated by reintroducing a British spelling and confirming the check failed the build.
Fixed a CKM card rendering inside the Lipid Management card on the Cardiology rotation page, and added a check so it cannot happen again. The two cards painted on top of each other and the CKM topic was unclickable from that grid. The cause was an insertion anchored on the lipid card's title line rather than on its closing tag: rotation cards come in a compact one-line form and a four-line form, and anchoring on the title is safe for the first and silently nests for the second. The other three grids that list CKM (nephrology, endocrinology, ambulatory) were checked and were correct, and a site-wide scan of all 288 topic cards found no other instance. Every existing check had passed, because the markup was perfectly balanced and structural integrity was intact; the card was simply in the wrong place, which no structural test can see. audit.js now reports this as a deploy-blocking finding, naming both the outer and inner element, and it rides along on the existing browser render at no added cost. The check was then extended to every card class on the site, not just rotation cards: it now covers all 9,539 card elements across roughly 30 classes, including summary cells, alert boxes, pearl cards, example boxes, trial cards, infographic cards and calculator cards. It flags only a card nested inside another card of the same class, which is always a mistake, while ordinary nesting inside a different container stays silent. Validated by reintroducing the bug, which correctly produced the finding and a failing exit code.
Every infographic is now US English. A sweep across all sheets found British spellings, UK drug names and UK dosing abbreviations. The drug names were the real problem: a resident searching the toxicology sheet for acetaminophen found nothing, because the sheet used the British name, and one antibiotic was listed under both a drug name and a dosing frequency that do not exist in US practice. Every sheet now uses the US name and US frequency: albuterol, epinephrine, norepinephrine, acetaminophen, succinylcholine, nafcillin, methimazole, amoxicillin-clavulanate, TMP-SMX and BID / TID / QID, plus the whole British spelling set. Genus and species names (Haemophilus, Entamoeba, Neisseria gonorrhoeae), journal titles and angioedema were deliberately left alone.
audit.js now enforces US English on every deploy. A new HIGH-severity check scans index.html and all infographic sources for UK drug names, dosing abbreviations and British spellings, so this cannot drift back. It strips tags before scanning (a naive pass would rewrite a CSS class name and break the stylesheet), scans script bodies because the pearls and trial database live there, and only suppresses a flagged word when an allowed term physically overlaps it.
All 189 infographics are now full-page. 14 sheets were leaving up to a third of the page blank and 3 crowded the footer; all now fill the page properly. 56 sheets were rebuilt and now have editable HTML sources, taking the library from 97 sourced sheets to all of them: every sheet in the library now has an HTML source, so no PDF ever has to be patched blind again. All 153 footer QR codes re-verified by machine decode after the rebuild.
Clinical content corrected on rebuilt sheets.Brain death still listed EEG as an ancillary test, which the 2023 AAN/AAP/CNS/SCCM guideline removed because EEG reads cortex and not brainstem. Cardiogenic shock predated DanGer Shock and ECLS-SHOCK. Anaphylaxis carried UK epinephrine dosing and the UK steroid position. Acute stroke used mmol/L glucose. COPD exacerbation used kPa units.
Acute pancreatitis expanded on complications, sheet and topic page together: the four Revised Atlanta collections (APFC, pseudocyst, ANC, walled-off necrosis), infected necrosis with PANTER and POINTER, abdominal compartment syndrome, splanchnic vein thrombosis, splenic artery pseudoaneurysm and disconnected pancreatic duct syndrome. The topic page also had a real error corrected: the pseudocyst row still gave the obsolete "> 6 cm" size threshold as a drainage indication.
SIADH: added why the uric acid is low (proximal urate reabsorption is coupled to sodium, which the volume expansion of water retention switches off), and removed the duplicated Diabetes Insipidus section, which has had its own full topic for some time.
Famous Cases: every answer now shows the person. All 8 reveal boxes carry a portrait (Phineas Gage daguerreotype with the tamping iron, JFK's White House portrait, the Ramsay coronation portrait of George III, the David portrait of Napoleon, the Stieler Beethoven, FDR's 1944 color portrait, Bob Marley on stage in Zurich 1980, and the Bristol statue of Henrietta Lacks, since no verified freely licensed photograph of her exists). Images are lazy-loaded inside the hidden answer box so nothing spoils the diagnosis before the reveal, and Creative Commons photos carry their required attribution. Cases also reordered most-famous-first: leading with instantly recognized figures hooks attention early, which is what makes the diagnosis stick.
Infographic fill pass: 37 sheets enriched, and one was outdated rather than merely sparse. A measurement of all 154 PDFs found every sheet passing the one-page check but 44 sitting in the sparse 700-729 band, leaving the lower third bare. Seven are now filled. Pulmonary embolism (#40) was the important one: it had no mention of the 2026 AHA/ACC guideline and still used the "massive / submassive" language that guideline retires. Rebuilt from the official at-a-glance around the Acute PE Clinical Categories A to E with subcategories, the disposition rules (Category A goes home from the ED, C to E are admitted), and three things that were entirely absent: systemic thrombolysis is Class 3 HARM in Categories A1-C2, PERT activation is Class 1 for C-E, and LMWH is now recommended over unfractionated heparin. The other six gained the numbers a resident would otherwise have to look up: IV antihypertensive doses (hypertensive emergency), CHA₂DS₂-VASc components and DOAC dosing with the renal cutoffs (AF with RVR), antianginal doses including the ranolazine-diltiazem cap (chronic coronary disease), D50 / D10, glucagon and octreotide dosing (hypoglycemia, which previously said only "intravenous dextrose"), and expected increments per product (transfusion: 1 unit of red cells raises Hb about 1 g/dL, and a failed increment is a finding rather than an inadequate dose). Every overshoot was resolved by cutting duplicated content first, never a safety item. All 154 remain single-page with 154/154 QRs verified. A second batch added the numbers behind interventions the sheets already named: the water-soluble contrast protocol (100 mL, film at 8 and 24 h, contrast reaching the colon predicts resolution) and neostigmine 2 mg IV with atropine at the bedside for Ogilvie syndrome; STOP-BANG risk bands and the 4 h on 70% of nights adherence standard in OSA; tranexamic acid within 3 h (CRASH-3), 7-day seizure prophylaxis, and anticoagulant reversal in raised ICP; dexamethasone dosing and catheter-related thrombosis management in SVC obstruction; and two safety facts in oncologic emergencies, that rasburicase is contraindicated in G6PD deficiency and that tocilizumab treats CRS but not ICANS and may worsen it. A third batch added nebulized tranexamic acid dosing (hemoptysis), thiamine 200-300 mg before any carbohydrate with the 10 and 5 kcal/kg starting rates (refeeding), perioperative DOAC and warfarin holds with the do-not-bridge rule from PAUSE and BRIDGE (VTE), when a steroid taper is and is not needed (corticosteroids), and the QTc-stacking and linezolid MAO-inhibitor cautions (antibiotic safety). A fourth batch supplied doses for interventions the sheets named but never quantified: heparin 80 units/kg bolus then 18 units/kg/h (acute limb ischemia, where the omitted bolus is the part that matters), isotonic saline at 1-1.5 mL/kg/h before and after contrast plus the point that metformin is a lactic-acidosis question, not a kidney one (contrast nephropathy), platelet transfusion thresholds of 10, 20, 50 and 100 (pancytopenia), vancomycin and ceftriaxone dosing with the reminder that antibiotics alone do not cure a septic joint (septic arthritis), and procainamide dosing with its three stop rules plus correct adenosine technique (tachyarrhythmia). A fifth batch added antidote and rescue doses that the sheets named but never quantified: cyproheptadine 12 mg then 2 mg every 2 h, dantrolene and bromocriptine (NMS and serotonin syndrome), infliximab 5 mg/kg or cyclosporine 2 mg/kg/day at the day-3 decision (acute severe colitis), terlipressin 1 mg every 6 h escalating at day 3, with oxygen saturation as the dose-limiting toxicity (hepatorenal syndrome), starting pressor doses (shock), and the four reversal-agent doses including andexanet low versus high dosing and protamine 1 mg per 100 units (anticoagulation). A sixth batch was chosen by measuring drug-name-to-dose ratio rather than by fill alone, which surfaced the sheets where agents were named but never quantified. Neutropenic fever listed nine antibiotics and zero doses despite a 60-minute clock, and now carries cefepime 2 g q8h, piperacillin-tazobactam 4.5 g q6h and meropenem 1 g q8h, plus the point that vancomycin is not routine and needs a specific indication. Cellulitis gained doses by phenotype, acute liver failure the full NAC regimen with the note that it helps in non-acetaminophen failure too, HIV the CD4 prophylaxis thresholds, and heat stroke the fact that antipyretics and dantrolene do not work because the hypothalamic set point is normal. A seventh batch targeted threshold sheets rather than drug sheets, since dose-count no longer identified the gaps. Added the tube and line positions (endotracheal tip 5 ± 2 cm above the carina, moving 2 cm with neck flexion; central tip at the cavoatrial junction) and the caution that cardiothoracic ratio only applies to a PA film, not the AP portable most inpatients get; numbers behind AEIOU with the point that refractoriness rather than the number decides dialysis; the disease-specific hospice criteria behind the 6-month prognosis; the Gurd criteria, which were absent from the fat embolism sheet entirely; and the three numbers separating RTA types, where type 4 is given away by a high potassium with a urine pH below 5.5. Sparse sheets are down from 44 to 8 and the median fill from 761 to 771.1. The final 8 were then audited one by one and deliberately left alone, because they turned out to be complete rather than sparse: immunotherapy toxicity, nutrition in critical illness, chest pain, pulmonary nodule, burns, cardiac tamponade, hypothermia and drowning, and necrotizing skin infection all already carry the numbers that define them, including the HEART bands with their MACE percentages, the Fleischner 6 and 8 mm thresholds, Parkland 4 mL/kg titrated to urine output rather than to the formula, pulsus paradoxus above 10 mmHg alongside right atrial and right ventricular diastolic collapse, LRINEC with the warning that it supports the diagnosis but does not exclude it, potassium above 12 mmol/L as a stop point with "not dead until warm and dead", and mycophenolate as the second-line agent in checkpoint-inhibitor hepatitis, where infliximab is avoided. They read low only because they are brief, dense topics. Filling them further would have been padding, which the fill rule explicitly forbids. Two measurement lessons were written into the process: low fill and drug-to-dose ratio are screens that say where to look, never evidence that something is missing, and a gap must be confirmed by naming the exact fact and searching for it with tags stripped and case ignored, because two of these sheets looked incomplete only because HTML tags split the phrases being searched for.
NEW INFOGRAPHIC #154: Outpatient Lipid Management, and two clinical corrections it surfaced. Building the sheet against the official ACC Guideline-at-a-Glance exposed errors already live on the site. (1) The apoB threshold was wrong in 8 places: the site said check apoB when TG > 200, but the 2026 guideline says TG ≥ 150 mg/dL. All corrected. (2) The non-HDL-C goals were missing entirely, despite "LDL-C and non-HDL-C treatment goals are back" being one of the guideline's top take-home messages: < 85 very-high-risk, < 100 high risk or standard ASCVD, < 130 borderline/intermediate. Now on the sheet. The sheet also adds what was absent: the guideline's own CPR framework (Calculate, Personalize, Reclassify), CAC upgraded from Class 2a to Class 1 with the men ≥ 40 / women ≥ 45 rule and the new counting of incidental calcium on non-gated CT, Lp(a) numeric thresholds (≥ 125 nmol/L is ~1.4× risk, ≥ 250 nmol/L is ≥ 2×) with cascade testing and the Class 1 PCSK9 mAb add-on, CKD stage 3-4 added to the treat-regardless-of-LDL list, and monitoring guidance including not checking LFTs or CK routinely. The lipid pages had a One Pager tab but no printable sheet behind it, only the older inline HTML. Built on the 2026 ACC/AHA dyslipidemia guideline: PREVENT risk bands, the numeric LDL goals (< 55 / < 70 / < 100), the five statin indications plus the new early-intervention category, intensity defined by percent reduction rather than milligrams, Lp(a) once per lifetime and apoB when LDL misleads, add-ons as parallel options rather than a ladder, and the situations that change the drug (TG thresholds and the gemfibrozil trap, the nocebo problem behind "statin intolerance", pregnancy stop-list, pitavastatin in HIV, and the rosuvastatin caps in CKD and Asian ancestry). First render passed at 702 pt but left the lower page bare; expanded to 788.8 pt of an 800 pt ceiling, which is what surfaced the omissions above. Library is now 154 sheets, all 154 QRs machine-verified.
Outpatient Lipid summary tightened. It had grown to 12 cells and roughly 4,000 characters, about double the site norm for a "one-screen" summary. Now 10 cells and about 2,200 characters, 45% shorter, keeping every clinical fact and the reasoning behind it while cutting the padding. The safety-critical cells were deliberately kept (pregnancy stop-list, never gemfibrozil with a statin); what went was the investigational Lp(a) drug pipeline, which changes nothing at the bedside today.
Search analytics rebuilt to capture failed searches. The search event previously fired only when someone clicked a result, which meant the most useful signal, the searches that returned nothing, was never recorded. It now fires on the query itself with a results_count parameter, recorded above the no-results branch so both outcomes are captured. It is debounced 1.2 s so a burst of keystrokes produces one event rather than one per letter, ignores queries under 3 characters as noise, and dedupes a held query. The click is now its own search_result_click event, so "what residents looked for" and "what they actually found" are finally separate questions. Verified in-browser: three rapid queries produced a single event, a nonsense query recorded results_count: 0, and a real query recorded 10 results followed by a distinct click event. Note this needs search_term, results_count, topic_id and destination registered as GA4 custom dimensions to be visible; the property currently has none registered, so every custom parameter the site sends is collected and then unqueryable, and registration is not retroactive.
Page titles now use a pipe separator. Titles were built as Hyponatremia -3-Step Approach -RoundsRx, and that tight space-hyphen reads like a typo in a search result. All 271 titles in index.html and 251 in the edge function now use Hyponatremia | 3-Step Approach | RoundsRx. The replacement targeted only space-hyphen, so genuine hyphens survived intact: GLP-1, Lung-Protective, 3-Step and Non-Hodgkin are unchanged. Five pieces of runtime code also parsed the old format to build breadcrumbs and share-email subjects, and were updated in the same pass, since otherwise every breadcrumb would have displayed the full title with its suffix still attached.
SEO: found and fixed the reason 249 of 263 pages were not indexed by Google. Search Console showed 14 pages indexed against 249 not indexed, with 144 "Crawled, currently not indexed" and 98 "Discovered, currently not indexed", and only 30 search clicks in three months. The May 2026 cycle had concluded this was an authority signal rather than a technical fault. That was wrong. Fetching two unrelated live URLs as a crawler sees them showed both serving the same block of oncology topics (oncologic emergencies, pancytopenia workup, chemotherapy toxicities), so every one of the 250 URLs carried a large identical content block, which reads as duplicate content and is exactly what produces those two Search Console states. Cause: the edge function's stripNonTargetViews() finds each view's end by counting div depth, and five views are missing their own closing tag (the browser silently recovers, a depth counter does not), so those views were never stripped. These were the same MEDIUM "unclosed-tag" findings the audit has reported for months and that were treated as cosmetic because the browser renders fine. Fix: the stripper now clamps every view's range at the next view's start, so a malformed view can no longer swallow its neighbors, with the last view bounded at </main> so the scripts and closing tags survive. Verified against the real file: previously 3 foreign views leaked into every page, now exactly 1 view is served per URL out of 250, roughly 86 KB smaller per page, with an unknown slug still safely returning the full document. A regression guard now runs in audit.js ("SEO view isolation"): it executes the real stripper against six representative URLs, including the first and last views, and fails the deploy if any URL serves more or fewer than exactly one view, if the target view is stripped, or if the document tail is destroyed. It was validated by reintroducing the bug, which correctly produced a HIGH finding and exit code 1. This class of defect was invisible for months because every existing check reads index.html, while the fault lived in the edge function that only crawlers ever see.
NEW TOPIC: Cardiovascular-Kidney-Metabolic (CKM) Syndrome. A 5-tab page (Staging / Screening / Management / Rounds / Summary) built on the 2026 AHA/ACC/ADA/ASN guideline (JACC, June 9, 2026), verified against the official ACC Guideline-at-a-Glance rather than press coverage. Covers the five stages 0 to 4 with the Stage 3 criteria spelled out (CAC above 100, NT-proBNP ≥ 125 pg/mL with echo dysfunction, very high-risk CKD, or PREVENT 10-year risk ≥ 20%) and the 4a/4b split by kidney failure; the stage-driven screening cadence (annual lipids, glycemia, BP and both eGFR and UACR from Stage 2, FIB-4 every 1 to 2 years for MASLD, pre-HF biomarkers at PREVENT-HF ≥ 5%); and the four CKD drug thresholds that are easiest to get wrong: RAS inhibitor at UACR ≥ 30 with eGFR ≥ 30, SGLT2i at UACR ≥ 200 with eGFR ≥ 20, finerenone added at UACR ≥ 30 despite both with eGFR ≥ 25, and GLP-1 added at UACR ≥ 100 despite both. Every recommendation carries its Class of Recommendation. Deliberately does not restate drug doses, which stay in the Obesity, T2DM and CKD topics and are deep-linked, so there is one place to maintain rather than five. Also captures the two reversals worth knowing: metformin has moved from mandatory first step to a Class 2a glycemic add-on, and BMI alone is no longer adequate without a waist circumference.
What's New: two 2026 guidelines added. The page had stopped at the March dyslipidemia guideline. Added the 2026 AHA/ACC/ADA/ASN Cardiovascular-Kidney-Metabolic (CKM) Syndrome guideline (JACC, June 9, 2026), which retires and replaces the 2013 AHA/ACC/TOS obesity guideline and reframes obesity, T2DM, CKD and CVD as one syndrome staged 0 to 4, with screening intervals set by stage and a therapy map spanning GLP-1 RA, SGLT2i, RAS inhibitors and finerenone. Also added the first-ever AHA/ACC acute pulmonary embolism guideline (Circulation, March 24, 2026), which retires massive/submassive language for Clinical Categories A to E, discharges Category A from the ED, and recommends PERT activation. Both were verified field by field against the primary publications rather than the press releases.
Hyponatremia: new iatrogenic section covering mannitol and post-TURP irrigant absorption. Both were missing entirely, and both are traps because the tonicity contradicts the sodium number. Mannitol is an effective osmole, so it causes hypertonic hyponatremia with an osmolal gap, where hypertonic saline is the wrong direction and the fix is stopping the drug; it also flips to hypernatremia in its osmotic-diuresis phase, so the sodium has to be followed both ways. Post-TURP glycine absorption causes genuinely hypotonic hyponatremia with hypervolemia, presenting with hypertension and bradycardia rather than the tachycardia and hypotension you expect intraoperatively, plus two glycine-specific toxicities: hyperammonemic encephalopathy that outlasts the sodium correction, and transient blindness that is the glycine and not a stroke. Includes an irrigant comparison table (glycine, sorbitol, mannitol, saline), why monopolar resection forces an electrolyte-free irrigant at all, why bipolar plus saline has made the syndrome rare, and the spontaneous-overcorrection warning as glycine is metabolized. Both conditions were also placed in the three diagnostic tables where the decision actually gets made, rather than only in their own section: the Step 1 osmolality table now separates post-TURP (hypo-osmolar, swells the brain) from mannitol (hypertonic, do NOT give hypertonic saline), Step 2 gained a fourth volume-status row for acute iatrogenic hypervolemia from post-TURP or operative hysteroscopy irrigant absorption, which is the one hypervolemic hyponatremia that still gets 3% saline, and Step 3 now lists the osmolal gap as a lab to send whenever mannitol or absorbed irrigant is in play.
Two new pearls (library now 729). "Mannitol causes hypertonic hyponatremia, so hypertonic saline is the wrong direction" (find the osmolal gap, stop the drug, expect the later flip to hypernatremia), and "transient blindness after a TURP is the glycine, not a stroke" (retinal inhibition plus ammonia-driven encephalopathy that outlasts the corrected sodium).
Corrected-sodium calculator: fixed an inverted term. The output called hyperglycemic hyponatremia "pseudohyponatremia". It is not: glucose genuinely pulls water out of cells and dilutes the sodium (translocational, hypertonic). Pseudohyponatremia is the lab artifact of severe hyperlipidemia or hyperproteinemia, where measured osmolality is normal. A site-wide scan confirmed the other seven mentions already separated the two categories correctly.
Famous Cases doubled: 8 new cases, 16 total. New additions with portraits: Abraham Lincoln (the Marfan vs MEN2B debate and why each theory has a different fatal complication to screen for), George Washington (acute epiglottitis, the 4 D's, and the junior physician whose tracheotomy call was overruled), Muhammad Ali (Parkinson's vs post-traumatic parkinsonism, and the under-40 Wilson's rule), Stephen Hawking (ALS: UMN + LMN signs without sensory loss, and what actually extends survival), Vincent van Gogh (episodic neuropsychiatric differential plus the digitalis xanthopsia board pearl), Marie Curie (radiation aplastic anemia and the pancytopenia workup), Queen Victoria (X-linked hemophilia B, confirmed by 2009 Romanov DNA analysis), and Typhoid Mary (chronic biliary S. Typhi carriage and quarantine ethics). All portraits are public domain. A Reveal All Answers toggle at the top serves second-pass review: first-timers keep the guess-the-diagnosis format (active retrieval is what makes the cases stick), while returning readers can open all 16 at once and skim.
Local file mode: images now load. Root-relative image paths (/images, /infographics thumbnails) resolve to the drive root when index.html is opened directly as a local file, so every portrait and thumbnail appeared broken offline. A small shim now rebases those paths onto the folder the file lives in when running under file:, captured before SPA navigation rewrites the URL. Production behavior on roundsrx.com is unchanged.
Summary tabs: last three bare-directive summaries rewritten. A site-wide scan of all 181 Summary sections found the improvement pass essentially complete, with three stragglers still in the old telegraphic style: Hyponatremia, Hyperkalemia and Hypercalcemia. All three now explain the why behind each move, including the urine-osm-then-urine-Na logic and the overcorrection rescue in hyponatremia, the treat-the-ECG-not-the-number rule and the delayed hypoglycemia after IV insulin in hyperkalemia, and the fluids-first rationale (hypercalcemia causes nephrogenic DI, so every patient arrives volume depleted) plus the FHH surgical trap in hypercalcemia.
Build stats recounted from source at deploy: 231 topics and tools, 15 rotations, 1,070 pimp questions, 1,803 trial citations, 1,165 alert flags, 569 clinical scenarios, 729 pearls, 189 infographics, 6,179 drug-table entries across 1,103 tables. Four tiles moved: the topic count is now measured rather than estimated (all 249 views minus the 15 rotation indexes and the dashboard, about and What's New pages), and trial, alert and drug-entry counts fell slightly because the removed Quick Reference sections took some with them. The OG image was regenerated to match, since it still advertised 250 topics and 153 infographics.
v5.6 - August 6, 2026
Pneumonia rebuilt on the 2025 ATS guideline. The update (published Jan 2026) reverses two things: steroids in severe CAP are now a conditional recommendation FOR (2019 suggested against), and in non-severe CAP the recommendation against is now strong. Duration got shorter, not longer: under 5 days with a 3-day minimum once clinically stable for outpatients and non-severe inpatients, while severe CAP keeps a 5-day floor as a strong recommendation. Two new questions were added: a detected respiratory virus in a healthy outpatient with no comorbidity means no antibiotics at all, and lung ultrasound is an acceptable alternative to chest radiography. Applied across the topic page, all four duration statements, the steroid tables, the workup, and the summary tiles, with a "what changed" box and per-row tags.
Pneumonia one-pager replaced. Series #23 was "Severe CAP", covering only ICU-level disease; it is now Community-Acquired Pneumonia spanning outpatient to ICU, and includes an explicit MRSA / Pseudomonas indications table showing that with risk factors but no prior isolation, non-severe CAP gets cultures and no empiric coverage while severe CAP gets both. Old severe-cap.pdf 301-redirects to the new file; series number preserved so printed QR codes still resolve.
New Hypokalemia one-pager (#151) covering severity and ECG, the replacement arithmetic, the magnesium/ROMK rule, and the urine K/creatinine workup.
Potassium replacement arithmetic corrected. The classic "10 mEq raises serum K by 0.1" is a best case, not an average: the real-world inpatient median is 0.05 mEq/L per 10 mEq (0.07 off potassium-affecting drugs, 0.03 on a loop diuretic). One protocols table also claimed "~0.3 mEq/L per 10 mEq", triple the classic rule and six times the observed median. Fixed in all five places, with the Kruse & Carlson and AJHP studies cited.
Duplicate Electrolyte Replacement pages merged. Two quick-reference pages shared the same title and sat next to each other in the homepage nav. They are now one page with Protocols, Rates & Safety, Sodium, and One Pager tabs, added to the ICU rotation. The retired page 301-redirects, and three dead references (page title, meta description, and a search-index entry pointing at a now-missing view) were removed.
Hyperkalemia one-pager expanded with a full type 4 RTA section, pseudohyperkalemia, an oral binder comparison, and insulin dosing in renal impairment. Also added to the Emergency Medicine rotation, which previously had no potassium emergency at all.
US English sweep. ~1,300 replacements across index.html, all 97 infographic sources, and the manifest: spelling, drug names (epinephrine, albuterol, acetaminophen, rifampin, cyclosporine), practice terms (NPO, the OR, labs), and lab units (fibrinogen mg/dL, albumin and hemoglobin g/dL). Eight British PDF filenames renamed with redirects. Journal titles, Haemophilus, angioedema and Leucovorin deliberately left alone.
Trial database cleanup. Removed four orphaned duplicate entries (ISIS-2, PROVE-IT, PARADIGM-HF, MADIT-II existed under both dash and underscore keys); the stale PARADIGM-HF copy carried the wrong N (8,442 rather than 8,399). Also cleared 33 em-dashes from calculator output and trial verdicts, so index.html now contains none.
SIADH rebuilt as a full Endocrinology page with new Workup, Management and Medications sections (all three were previously stubs), a causes table, and a new comparisons tab holding SIADH vs diabetes insipidus and SIADH vs cerebral salt wasting. The CSW table covers the trap that low uric acid does not separate them and that fractional excretion of urate only discriminates after the sodium is corrected (normalizes below 11% in SIADH, stays above in CSW), plus the warning never to fluid restrict a hyponatremic SAH patient.
Four broken pages repaired. Malformed table markup was silently corrupting the DOM: SIADH lost its entire treatment section (fluid restriction, hypertonic saline, tolvaptan and the ODS warning rendered nowhere), and SIADH, ILD and Leukemia had 6 to 7 sections each reparented into the Blood Transfusion Guide by the browser's parser. Also fixed an unclosed table in Lower GI Bleed and a section headed "Sarcoidosis" that actually contained the IPF antifibrotic table. All 1,427 section anchors now resolve to their correct parent view, verified against the source in a live DOM check.
Infographic Library search added, filtering all 151 cards by name, topic, category or series number with multi-word matching, a live count and collapsing category headings. Also merged a duplicate Haematology / Hematology category that had been rendering two identical headings and splitting the sheets between them.
Build stats recounted from source: 249 topics and tools, 15 rotations, 727 pearls, 1,074 pimp questions, 1,859 trial citations, 1,168 alert flags, 28 calculators, 566 clinical scenarios, 151 infographics, and 202 trial database entries. OG image regenerated.
v5.5 - July 30, 2026
Infographic Library expanded to 150, up from the 56 that shipped in v5.4. The library index is now verified complete in all three directions: 150 PDFs on disk, 150 cards, 150 distinct assets referenced, with no card pointing at a missing file, no file left uncarded, and nothing embedded in a topic that is not also in the library. 145 of 202 topic views now embed an infographic under the One Pager tab. Eight infographics currently live in the library only, without a parent topic embed: common ICU infections, HAP/VAP, antibiotic safety, ventilator weaning and SBT, raised ICP/TBI, nutrition in critical illness, tracheostomy emergencies, and endocrine emergencies.
Infographic Library headline corrected, it previously claimed that every infographic was also embedded in its parent topic under the One Pager tab. That is true for 142 of 150, not all of them, so the sentence now reads "most" rather than "each one."
Palliative Extubation: cross-topic template residue removed. Three blocks of pulmonary embolism content had been copied into the Rounds section of the palliative extubation view: an "Escalation Triggers / Activate PERT" alert calling for troponin and BNP trending, repeat echo for RV function, and vasopressor escalation; a "Transition to Oral Anticoagulation" block with full DOAC and warfarin bridging doses; and a "Follow-Up After Discharge" block covering CTEPH screening, thrombophilia workup, and age-appropriate cancer screening. On a comfort-care withdrawal page this was clinically wrong, and the escalation block directly contradicted the same page's own guidance a few lines above it, which correctly instructs you to remove SpO₂, BP, and HR displays because the goal is comfort rather than survival or physiologic targets. All three blocks were self-contained sections, so removal was a clean excision. Div structure verified balanced and the pre-deploy audit passes clean.
Build stats refreshed and recounted from source: 250 topics and tools, 15 rotations, 727 pearls, 1,068 pimp questions, 1,857 trial citations (up from the 1,771 shown since v5.4), 1,161 alert flags, 28 calculators, 566 clinical scenarios, 150 infographics, and 6,050 drug-table entries across 1,079 tables. Two new cells added to the Build Stats grid, Clinical Pearls and Infographics, neither of which had been surfaced there before. Also corrected the About intro, which read "245 clinical topics and tools" while the stats grid directly below it said 250.
Dashboard rotation topic counts recounted, every rotation card except Palliative Care was understating its own size, in some cases badly. Each count is now derived from the topic cards actually listed inside that rotation view: ICU 23 to 26, Cardiology 16 to 25, Pulmonology 10 to 14, Gastroenterology 12 to 19, Nephrology 11 to 14, Infectious Disease 12 to 22, Neurology 9 to 11, Emergency Medicine 11 to 16, General Wards 10 to 33, Hematology/Oncology 19 to 24, Endocrinology 16 to 17, Ambulatory 23 to 25, and Rheumatology corrected downward from 10 to 8. General Wards is the largest because it deliberately reuses cross-cutting topics (sepsis, CAP, AKI, hyperkalemia) that also live under their own specialty rotations, so the 282 total across all rotation cards counts shared topics more than once by design.
OG image regenerated with a fourth stat, 150 Infographics, alongside 250 topics, 15 rotations, and 1,068 pimp questions. Stats row went from a 3-column to a 4-column flex layout with the gap reduced from 120px to 90px to stay inside the 1040px content width.
Metadata and freshness pass: the "240 evidence-based protocols" claim was corrected to 250 in all five places it appeared (og:description, twitter:description, JSON-LD description, the Netlify edge function's dashboard description, and the PWA manifest). Structured-data dateModified and lastReviewed refreshed to 2026-07-30 in both the static head block (was 2026-05-01) and the dynamic per-topic block (was 2026-03-07). Sitemap lastmod updated only for the pages that actually changed this cycle (home, About, palliative extubation, infographic library) rather than blanket-bumping all 248 URLs, since lastmod should reflect real edit dates. Service worker cache bumped to roundsrx-v15 so returning users pick up this build instead of a cached copy.
v5.4 - July 23, 2026
NEW TOPIC: Cyclosporiasis (Cyclospora cayetanensis), full 8-tab view (Overview / Workup / Management / Medications / Prevention / Rounds / Summary / One Pager) under the Infectious Disease rotation, tagged 2026 OUTBREAK. Built around the active 2026 US cyclosporiasis surge (CDC Health Alert Network HAN00531): 4,173 lab-confirmed domestic cases plus more than 7,400 probable since May 1, 2026, more than 6× the prior season, with a traceback investigation of 1,645 confirmed cases across 34 states (age 2 to 95, median 44, 56% female). Source identified as shredded iceberg lettuce (Taylor Farms de Mexico) served at Taco Bell locations in Indiana, Kentucky, Michigan, Ohio, and West Virginia; all central-Mexico-sourced iceberg lettuce recalled July 17, 2026. Clinical content covers the fecal-oral (not person-to-person) transmission and why hospital contact precautions are not needed (oocysts must sporulate in the environment first), the ~7-day incubation, the hallmark prolonged, relapsing watery diarrhea with disproportionate fatigue, anorexia, and weight loss, and the central teaching trap: routine stool ova-and-parasites does NOT detect Cyclospora, so you must specifically order molecular GI PCR panel (preferred), modified acid-fast stain (variably acid-fast, oocysts 8 to 10 µm), or UV autofluorescence, and collect 2 to 3 specimens on different days because shedding is intermittent. Treatment section: TMP-SMX DS 1 tab PO BID × 7 to 10 days as the only reliably effective agent (prevents the characteristic relapse), the sulfa-allergy problem (no highly effective alternative; nitazoxanide 500 mg BID × 7d or ciprofloxacin 500 mg BID × 7d as fallbacks), and immunocompromised management (higher-dose/longer course + suppressive TMP-SMX 3×/week). Includes a Prevention tab (washing does not reliably remove oocysts; cooking kills them; nationally notifiable), 5 pimp questions, 3 bedside cases (outbreak-linked, sulfa-allergic, advanced-HIV), a Summary grid, and a printable one-pager. All clinical facts verified against CDC Cyclosporiasis clinical guidance, the CDC HAN notice, and Merck Manual Professional. Wired into the Infectious Disease rotation page next to the Hantavirus and Ebola 2026 OUTBREAK topics.
NEW: Infographic Library (56 one-page visual summaries), a new id="infographic-library" view under the Tools nav group collecting the full RoundsRx Infographic Series. 56 print-ready A4 PDFs grouped into 10 categories (Sepsis & Infection 12, Cardiovascular 10, Respiratory 7, Toxicology & Emergencies 6, Gastro & Hepatology 5, Neurology 5, Renal & Metabolic 5, Airway & Procedures 2, General ICU Care 2, Hematology 2). Each card shows a preview thumbnail and opens the vector PDF, which stays sharp when zoomed or printed. 47 of the 56 are also embedded directly in their parent topic under the One Pager tab: 28 replaced an existing HTML one-pager, 14 got a brand-new One Pager section and tab (necrotizing fasciitis, RSI, acute liver failure, malignant hyperthermia, fat embolism, PADIS sedation/delirium, fungal infections, brain death, massive transfusion, radiology quick-ref, anticoagulation reversal, hyperkalemia, antibiotics, anaphylaxis), and 5 were appended to quick-reference views that have no tab structure (ACLS, vasopressors, inotropes, electrolyte replacement, shock/differential trees). Search is preserved: where an infographic replaced an HTML one-pager, the original text was retained inside a collapsed "Text version" block, so every term stays findable through global search and readable by screen readers. All asset paths are root-relative (/infographics/...) so they resolve correctly on SPA deep links rather than 404-ing under the topic path.
NEW TOPIC: Ebola Virus Disease, 6-tab intern-focused view (Overview / Workup / Management / Prevention / Rounds / Summary) under Infectious Disease rotation. Built around the active 2026 Bundibugyo outbreak in DRC and Uganda (WHO PHEIC declared May 17, 2026; 121 confirmed + 17 deaths in DRC, 7 confirmed + 1 death in Uganda as of May 26, 2026; Italy travel scare returned negative). Covers the five ebolavirus species with side-by-side case-fatality and approved-MCM table making the "Inmazeb, Ebanga, and Ervebo are Zaire-only" caveat unmissable, transmission modes (including persistent virus in semen / eye / breast milk for survivors), four clinical phases (early febrile → wet/GI → critical/shock → recovery or death), triage red flags (fever + 21-day exposure to outbreak country), the CDC Identify-Isolate-Inform playbook with CDC EOC 770-488-7100, "What NOT to do until cleared" red box (no central lines, no LP, no routine labs, no aerosol-generating procedures), differential with "always rule out malaria first" for sub-Saharan returning travelers, supportive care backbone (balanced crystalloid not large-volume NS, strict electrolyte/glucose repletion, norepinephrine first-line, empiric antimalarial and ceftriaxone), Inmazeb vs Ebanga PALM 2019 trial data with explicit Zaire-only labelling, layered PPE with trained-observer doffing as the highest-risk step, Ervebo (rVSV-ZEBOV-GP) ring-vaccination strategy with Zaire-only caveat repeated, contact tracing tiers, returning-traveler counseling, and 6 pimp questions including the "what kills patients with Ebola is not hemorrhage" framing. Wired into Infectious Disease rotation page with 2026 OUTBREAK tag.
Pimp Me: lightweight spaced-repetition controls, the quiz page now has three retention tools layered over the existing 1,061-question bank (no new content, just a smarter engine): 🔀 Shuffle (randomizes order each session to break position-memory), ★ Mark for review + ★ Review only (star weak questions and drill just those), and 👁 Hide known (✓ Got it removes mastered questions so you stop re-seeing them). Stars and known-marks persist per device via localStorage (roundsrx_pimp_v1), counts show live in the toolbar, and "Clear stars/known" resets. Navigation now walks a filtered working-list rather than the raw priority order. First step toward true interval scheduling if usage warrants it.
Nephrology: Drug Dosing in Renal Impairment reference, new id="renal-drug-dosing" section in the CKD Medications tab. Six why-driven tables (~37 drugs) covering the STOP/avoid list (NSAIDs, metformin, nitrofurantoin, glyburide, spironolactone, IV bisphosphonates, sotalol, group-I gadolinium), antibiotics (vancomycin, aminoglycosides, cefepime neurotoxicity, vanc+pip-tazo AKI, carbapenems, fluoroquinolones, TMP-SMX pseudo-Cr-rise, acyclovir), anticoagulants (apixaban as preferred DOAC + 2-of-3 reduction, dabigatran/rivaroxaban/edoxaban thresholds incl. the edoxaban >95 paradox, enoxaparin 1 mg/kg daily <30), diabetes (SGLT2i initiate ≥20/25 and continue to dialysis, glipizide-over-glyburide, insulin reduction, linagliptin no-adjust), cardiovascular (digoxin, renally-cleared beta-blockers, ACEi/ARB ≤30% Cr-rise rule, rosuvastatin max 10 if eGFR<30), and analgesia/neuro/misc (gabapentinoids, morphine M6G accumulation, allopurinol titrate-to-target, colchicine, lithium, iodinated contrast). Every row states the GFR/CrCl threshold, the action, the why, and a renal-friendly alternative ("use instead" column): e.g., acetaminophen for NSAIDs, apixaban/warfarin for the other DOACs, atorvastatin for rosuvastatin, denosumab for IV bisphosphonates, febuxostat (with CARES caveat) for allopurinol, fentanyl/hydromorphone for morphine, metoprolol/carvedilol for renally-cleared beta-blockers, group-II gadolinium for group-I. CrCl calculator linked; thresholds verified against KDIGO/ADA 2025 and current labels. Deep-linked into the section from four sibling topics where the question arises: AKI (medication review step), antibiotics (renal-dose table cross-reference), anticoagulation (DOAC renal dosing), and outpatient diabetes (metformin dose-by-eGFR).
Heart Failure: BNP / NT-proBNP interpretation section, new id="bnp-interpretation" block in the Acute HF Workup tab. Two why-driven tables, conditions that raise BNP (cardiac: HF, AFib, ACS, valvular, myocarditis; non-cardiac traps: age, CKD, PE, pulmonary HTN/COPD, sepsis, female sex, anemia/high-output) and conditions that keep it deceptively low despite real HF (obesity via NPR-C clearance, hyperacute flash edema, HFpEF, constrictive pericarditis/tamponade, compensated chronic HF). Plus a clearance-mechanism box explaining the BNP-vs-NT-proBNP differences and the ARNI trap from one fact (BNP cleared 3 ways including neprilysin; NT-proBNP renal-only): why CKD raises NT-proBNP more, obesity lowers BNP more, and why sacubitril/valsartan makes BNP unreliable so NT-proBNP is the marker to trend on Entresto. Age-adjusted NT-proBNP cutoffs included, plus a "Which to order: BNP vs NT-proBNP" decision box (equivalent for dx/prognosis so use what the lab runs; NT-proBNP if on an ARNI; lean BNP in advanced CKD; never compare values across assays, trend the same one). Five passing BNP mentions site-wide (STEMI, qr-labs, lab-guide, TACO/TRALI discriminator, and the HF workup row) deep-linked to this canonical section. ARNI-affects-BNP caveat propagated to the chronic HF GDMT topic (Congestive HF GDMT monitoring table + workup), since that topic recommends ARNI as pillar #1 while also recommending BNP trending, the two collide, so both monitoring mentions now flag "on Entresto, trend NT-proBNP not BNP" with a deep-link back to the why.
Palliative Care: intractable hiccups expanded + accuracy fix, the existing “Hiccups > 48h” subsection (id="intractable-hiccups") rebuilt into a full singultus reference, definitions (acute <48h / persistent >48h / intractable >1 month), the reflex-arc rationale for the broad differential, causes ordered by frequency (GI, drugs incl. dexamethasone, CNS/Wallenberg with stroke deep-link, phrenic-vagus irritation, metabolic), targeted workup, and a corrected treatment ladder. Clinical fix: chlorpromazine was mislabeled first-line; per current evidence baclofen and gabapentin are first-line (tolerability) with chlorpromazine the only FDA-approved agent but held in reserve (sedation, hypotension, QTc, EPS). Same correction propagated across the topic’s symptom-overview table, summary cell, and one-pager so all four mentions agree.
ITP: pseudothrombocytopenia callout, new id="pseudothrombocytopenia" box in the ITP Workup tab making it the "rule out FIRST" step for any isolated low platelet count. Covers the EDTA / GPIIb-IIIa / calcium-chelation clumping mechanism, the smear-confirms-clumps diagnostic step, and the key nuance that a manual count on the same clumped EDTA tube is also falsely low (clumps defeat any counting method), so the fix is removing the clumping, redraw in citrate (×1.1 dilution correction) or heparin, and/or warm to 37°C, not switching counting technique. Closes with why it matters (avoid needless transfusions, steroids, marrow biopsy, held anticoagulation).
Acid-Base: Cohen-Woods classification + D-lactic acidosis, new dedicated id="cohen-woods-lactic-acidosis" section in the Acid-Base topic. Two-type framework (A = hypoperfusion/hypoxia, B = everything else) with B1 (underlying disease: liver failure, malignancy, sepsis, thiamine deficiency, short bowel/SIBO), B2 (drugs/toxins: metformin, linezolid, propofol, NRTIs, β₂ agonists), B3 (inborn errors: mitochondrial, PDH deficiency). New D-lactic acidosis alert covers the SIBO/short-bowel mechanism (gut bacteria ferment carb to D-lactate, the stereoisomer humans cannot clear), episodic encephalopathy presentation, and the standard lactate assay measures L-lactate only trap (order a D-lactate level specifically). Sits inside Type B1 in Cohen-Woods.
Milk-alkali syndrome deep section in Hypercalcemia, dedicated id="milk-alkali-syndrome" breakdown (CaCO₃ antacids + milk → hypercalcemia + AKI + alkalosis triad, mechanism, classic vs modern presentation, distinguishing from other hypercalcemia causes). Cross-linked from the Acid-Base CLEVER PD "Excess alkali" row using the established showView + scrollIntoView deep-link pattern so the passing mention navigates directly to the deep explanation.
Pneumonia: severe-CAP definition + steroids-in-pneumonia sections, new id="severe-cap-definition" section makes ICU-disposition criteria explicit (IDSA/ATS major and minor criteria) so the "severe CAP" label triggers cefepime + vancomycin per SSC 2026 rather than ceftriaxone + azithromycin. New id="steroids-in-pneumonia" section covers when steroids help (severe CAP / refractory shock, CAPE COD 2023), when they do not (non-severe CAP, viral pneumonia), and which steroid + dose.
ACS Overview: 2025 guideline-changes summary section, new id="acs-2025-guideline-changes" section consolidates what changed in the 2025 ACC/AHA ACS guideline at a glance (DAPT duration shifts, P2Y12 selection nuances, routine PRECISE-DAPT/DAPT-score risk-tiered de-escalation) with tag-driven NEW / CHANGED / UNCHANGED columns following the editorial "always state guideline changes" rule.
Second SEO/indexing acceleration pass, follow-up to the v5.2 cycle: (1) ran indexnow-submit.js a second time pushing all 247 URLs to api.indexnow.org (200 OK), Bing IndexNow (200 OK), and Yandex IndexNow (202 Accepted); (2) diagnosed the GSC "Crawled - currently not indexed" validation failure (135 pending, 3 failed as of May 2, 2026) - verified via curl-as-Googlebot that the live edge function correctly serves per-URL unique title, self-canonical, unique meta description, JSON-LD MedicalWebPage schema, X-Robots-Tag: index, follow, ~18 KB of unique visible text per page, and strips 245 sibling views per request (only 1 target view div + 245 stripped placeholders served); (3) sitemap.xml lastmod bumped to 2026-05-27 only for genuinely-changed entries (homepage, dyslipidemia-guideline-2026, outpatient-lipid-management, type-2-diabetes-outpatient) - deliberately did NOT blanket-bump unchanged URLs since Google detects fake freshness and penalizes it; (4) orphan-URL cleanup: caught two stale sitemap entries (/inpatient-insulin-management and /toxicology-toxidromes-antidotes) whose view divs had been renamed to /inpatient-diabetes-management and /toxicology-drug-overdose. The edge function's safety-bail was serving the dashboard for these URLs, creating exactly the duplicate-content signal that drives "Crawled - currently not indexed". Added 301 redirects in _redirects and pulled the stale entries from sitemap.xml. Conclusion documented: "Crawled - currently not indexed" is now a quality/authority signal, not a technical bug; resolution path is backlinks + time + "Request Indexing" per-URL in GSC, not more code changes.
NEW TOPIC: Hantavirus (HPS & HFRS), full 8-tab view (Overview / Workup / Management / Medications / Prevention / Rounds / Summary / One Pager) under Infectious Disease rotation. Built around the active 2026 M/V Hondius cruise-ship outbreak (Andes virus, person-to-person transmission documented, 5 confirmed + 3 suspected cases as of May 6, 2026). Covers HPS vs HFRS comparison, 2026 outbreak alert front-and-center, US epidemiology with Hackman/Arakawa context, β3-integrin endothelial pathophysiology, four phases of HPS, diagnostic triad (thrombocytopenia + hemoconcentration + immunoblasts), 11-step management package with VA-ECMO criteria (50–65% survival vs 35% without), ribavirin caveat (works in HFRS, NOT HPS), Andes airborne/droplet precautions, and a comprehensive Prevention tab with FAQ-format SEO content (CDC bleach-based cleanup, rodent-proofing, cabin protocol, traveler precautions for 2026 outbreak, healthcare worker tiers).
NEW TOPIC: Calciphylaxis (Calcific Uremic Arteriolopathy), full 7-tab view under Nephrology rotation. Covers MGP/warfarin pathophysiology, modifiable-vs-non-modifiable risk factor table, painful retiform purpura presentation, central vs peripheral lesion prognosis (~80% vs ~50% mortality), 12-step coordinated management package (sodium thiosulfate 25 g IV after each HD, switch warfarin → apixaban, stop Ca-based binders, aggressive phosphate control, calcimimetics, vitamin K, conservative wound care, multimodal pain), explicit "What NOT to Do" red box, dedicated Ca × P product formula callout with thermodynamic rationale (target < 55 mg²/dL², albumin-corrected Ca formula, KDIGO 2017 caveat), and 5 pimp questions including the warfarin-MGP mechanism.
Status Epilepticus major expansion, post-ictal LFT gotcha (AST > ALT pattern is muscle not liver), comprehensive post-ictal lab timing reference table (19 markers sorted fastest-to-slowest decay: lactate / prolactin / anion gap / WBC / cortisol / glucose / ammonia / myoglobin / troponin / AST / ALT / CK / aldolase / K⁺ / phosphate / Ca / urine myoglobin / Cr / LDH), "Why bilirubin isn't on the post-ictal list" callout (myoglobin → urine vs hemoglobin → bilirubin), GTC vs syncope vs PNES discriminator table, brand names added throughout the protocol (Ativan, Versed, Keppra, Depakote, Cerebyx, Diprivan, Ketalar, Vimpat), max doses for valproate/fosphenytoin in Phase 2, IM midazolam weight cutoff (10 mg if ≥ 40 kg, 5 mg if 13–40 kg), thiamine 100 mg IV before/with D50W in Stabilize step, "Why fosphenytoin not phenytoin" inline parenthetical (3× faster infusion, no purple-glove necrosis, less propylene-glycol cardiotoxicity, IM option). Lacosamide (Vimpat) added as Phase 2 fourth alternative (200–400 mg IV load) for benzo-refractory SE when LEV/VPA/PHT contraindicated.
NEW SECTION: Discharge & Outpatient AED Regimen in Status Epilepticus Medications tab, covers (1) decision to start AED based on recurrence risk, (2) seizure-type-specific selection table (focal / GTC / absence / myoclonic with first-line / alternatives / avoid columns), (3) maintenance dosing reference table for 10 AEDs (Keppra / Lamictal / Vimpat / Trileptal / Tegretol / Depakote / Topamax / Dilantin / Zonegran / Briviact) with side effects ordered by importance not frequency (life-threatening first, then teratogenicity, then dose-limiting, then common-tolerable, then PK), (4) special populations (pregnancy preferred lamotrigine/levetiracetam, elderly, CKD, hepatic), (5) discharge counseling checklist (state-specific driving, adherence, triggers, bone health, SUDEP), (6) drug-drug interactions (carbapenem × VPA red alert, enzyme inducers vs OCP/warfarin/DOACs/immunosuppressants, lamotrigine × VPA halve dose, lamotrigine × estrogen-OCP cycling). Empirical pyridoxine for Keppra behavioral SE clarified as supraphysiologic adjunct, not deficiency repletion.
STEMI P2Y12 rationale expanded, replaced bare "STEMI is different from NSTEMI" line with full explanation of why STEMI gets P2Y12 upfront (diagnosis certain, destination certain, CABG-needing anatomy ~3–5%, pre-loading reaches therapeutic platelet inhibition by stent deployment) vs NSTEMI defers to PCI time (~10–15% need CABG, pre-loaded prasugrel/ticagrelor force 5–7 day off-antiplatelet wait). Added ACCOAST, 2013 citation establishing that upstream prasugrel in NSTEMI is harmful.
Massive Transfusion Protocol Cycle 1 update, 5 new sections in Management tab: Whole Blood (LTOWB) as preferred initial product per AAST/ACS 2024, TBI changes the rules red alert (MAP ≥ 80, INR < 1.4, plt > 100K, hypertonic saline 3%/23.4%, no permissive hypotension), Hyperkalemia from stored blood (stored RBCs leak K⁺ to 30–40 mEq/L by day 35, washed RBCs option, dialysis if refractory), TRALI vs TACO discriminator table (mechanism, onset, vital signs, BNP, CXR, echo, treatment, mortality, with "if unsure treat as TACO first" pearl), and Anticoagulation Reversal table (apixaban/rivaroxaban → andexanet alfa with ANNEXA-4/I cite, dabigatran → idarucizumab with REVERSE-AD cite, warfarin → 4F-PCC + vitamin K with Sarode 2013 cite, UFH → protamine, LMWH → partial protamine, antiplatelets → platelets + DDAVP with PATCH 2016 caveat, fondaparinux → no specific reversal). Defining thresholds in MTP Overview now bolded for emphasis.
SEO & indexing acceleration cycle, (1) Hantavirus & Calciphylaxis added to og-tags.js edge function (per-URL title + meta description for both); (2) sitemap.xml updated with both URLs (Hantavirus priority 0.95 weekly for outbreak news, Calciphylaxis priority 0.8 monthly); (3) Bing Webmaster Tools verification meta tag added to head section (msvalidate.01 = 74DDB20FB23F08D10C5E676DAB2F59EA), site verified live; (4) BWT sitemap submitted, URL inspection submitted for Hantavirus + Calciphylaxis (Bing 100 URLs/day quota); (5) IndexNow batch script (indexnow-submit.js) pushes all 247 URLs to Bing/Yandex/IndexNow.org in one call, run twice in this cycle (pre-deploy + post-deploy with related-topics content); (6) Google Search Console sitemap resubmitted, Hantavirus + Calciphylaxis URL Inspect + Request Indexing submitted to priority queue; (7) diagnosed root cause of 122 "Alternate page with proper canonical" GSC issue (last crawl Mar 26, 2026 was before edge-function canonical rewrite was working; verified via curl-as-Googlebot that current served HTML now has correct per-URL canonical, just awaiting Google re-crawl).
Internal linking pass: Related Topics auto-injection on 179 clinical topics, every clinical-topic view now ends with a "Related Topics" footer linking to 4–6 sibling topics from the same rotation (~900 new internal-link signals across the site). Templated, idempotent (script checks for existing data-related="1" before re-inserting), uses regex-anchored injection at topic-content close. Addresses 98 GSC "Discovered, currently not indexed" pages by giving each orphan-like topic a fresh crawl path from indexed siblings. Audit-verified: 247 views, 1331 section anchors, 0 orphan tabs, 0 duplicates, 0 content quality issues.
Editorial rule formalized, side-effect lists now ALWAYS ordered by importance not frequency (hierarchy: life-threatening / boxed warnings / "stop the drug" first → pregnancy/teratogenicity → suicidal ideation/class effects → dose-limiting common SE → common-but-tolerable → PK/dosing notes). Applied retroactively to all 10 AEDs in the new outpatient AED maintenance table. PRIS expanded inline to "propofol infusion syndrome (PRIS)" across 5 site-wide first-use locations (Status Epilepticus management, Status Epilepticus rounds, Mech Vent guide, PADIS sedation, RSI). Calciphylaxis valproate redundant profile box removed once meds-table row + Step 6 interactions section covered the same content (added unique "VPA raises phenobarbital + warfarin" + "enzyme inducers lower VPA" callout to preserve the unique interaction info).
NEW TOPIC: 2026 ACC/AHA Dyslipidemia Guideline -2018 vs 2026 Comparison, dedicated standalone view (mirroring the SSC 2026 comparison page) with 20-row side-by-side table covering scope (Blood Cholesterol → Dyslipidemia), risk calculator (PCE → PREVENT-ASCVD), risk bands (<5/5-7.5/7.5-20/≥20% → <3/3-<5/5-<10/≥10%), numeric primary-prevention LDL goals for the first time (PREVENT ≥10% → <70, 5-<10% → <100), secondary-prevention split into very-high-risk (<55, apoB <55) vs standard (<70), routine Lp(a) once per lifetime + apoB targets aligned with LDL goal (<55/<70/<90), early-intervention category (HeFH at diagnosis incl. age 8-10 / age ≤30 LDL ≥160 / strong family hx / high 30-yr PREVENT), expanded DM (age 30-39 if LDL ≥160 or elevated 30-yr PREVENT), parallel non-statin add-ons (ezetimibe / bempedoic acid / PCSK9i mAb / inclisiran), HIV REPRIEVE 2023 recommendation. Three tabs: Side-by-Side, Key Changes, New in 2026. Trials supporting the changes documented (FOURIER, ODYSSEY OUTCOMES, REDUCE-IT, ORION, PROMINENT, CLEAR Outcomes, REPRIEVE, PREVENT, CTT meta-analysis).
Outpatient Lipid Management refresh, Overview now leads with a brief 8-row 2018 vs 2026 comparison snippet + "→ Full 2018 vs 2026 Comparison" link to the dedicated comparison view. Replaced the prior multi-paragraph "What changed in March 2026" alert with the more scannable snippet table.
Lipid management accuracy refinement, apoB target tiers corrected to the 2026 ACC/AHA-endorsed three-tier scheme `<55 / <70 / <90` aligned with the LDL goal (very-high-risk <55 → apoB <55; standard ASCVD or high-risk primary prevention <70 → apoB <70; intermediate / borderline <90). DM age 30-39 statin expansion language corrected to the 2026 ACC/AHA criterion: "LDL ≥160 or elevated 30-year PREVENT" (replaces ADA-style "duration ≥10 yr or microvascular disease" framing). Fixes applied across the new comparison view, the existing outpatient lipid topic, and the PREVENT calculator output.
AECOPD steroid dose corrected, methylprednisolone reverted from 125 mg IV (anaphylaxis-style dose, erroneously added in v4.3) back to 60 mg IV daily = prednisone 40 mg PO × 5 days per GOLD 2026, the actual COPD-exacerbation regimen. Dexamethasone alternative corrected from 8 mg to 6 mg (8 mg ≈ 53 mg prednisone, exceeds the GOLD 40 mg target). Same drug, same route can have very different correct doses across indications.
Resistant HTN wording fix, "Adherence is the #1 reason" inverted-polarity error corrected to "Non-adherence" in 3 places (Resistant HTN tab, summary alert, Quick Reference card). The desired-behavior word was being labeled as the cause of failure.
HTN follow-up rationale added, bare "BMP q6-12 months" directive expanded with the why: monitor for thiazide effects (hypokalemia, hyponatremia, hyperuricemia) and RAAS-inhibitor effects (hyperkalemia, Cr bump). Recheck within 1-2 weeks of any uptitration.
Insulin DKA drip dose alignment, DKA case examples and step-by-step now state both ADA-acceptable patterns: no bolus + 0.14 units/kg/hr, or 0.1 u/kg bolus + 0.1 u/kg/hr drip. Removed the "no bolus + 0.1 u/kg/hr" hybrid (under-dosed because it omits the loading effect of the bolus).
Other clinical accuracy fixes, PE prevalence in AECOPD corrected from "up to 25%" to "~12-16%" (Aleva 2017); PRORATA 2010 (sepsis ICU) replaced with ProHOSP 2009 for PCT in AECOPD; asthma NIV ">80% avoid intubation" corrected to "65% RR reduction" (Cochrane Osadnik 2017); asthma NIV starting IPAP corrected from 8-10 to 10-12 (BTS); ARDS Munshi 2017 tooltip rewritten (was a multiple-myeloma paper); AHF ADVOR result clarified ("12% absolute increase, NNT <9, RR 1.46" replaces the ambiguous "46% more decongestion"); Adrenal Crisis case scenario reversed (give dexamethasone if checking cortisol, does not cross-react with cortisol assay; AVOID hydrocortisone, which does cross-react).
v5.0 - April 28, 2026
NEW TOPIC: Outpatient Lipid Management, 7-tab view built around the 2026 ACC/AHA Multisociety Dyslipidemia Guideline (released March 13, 2026). Covers the 5 statin indications (clinical ASCVD, severe LDL ≥190, DM, primary prevention by PREVENT, NEW early-intervention category for HeFH / age ≤30 LDL ≥160 / strong family hx / high 30-yr PREVENT), 2026 LDL targets (very-high-risk <55 / standard ASCVD <70 / primary prev <70 high / <100 intermediate), routine apoB and Lp(a) testing, "lower for longer" cumulative-exposure framing, and explicit "vs 2018 guideline" comparison columns with NEW / CHANGED / EXPANDED / EARLIER START / UNCHANGED tags on every row. Wired into Cardiology and Ambulatory rotation pages plus search index.
PREVENT calculator integration, every PREVENT body-text mention in the Lipid topic (21 calc-links across headline, alerts, indications table, LDL targets table, risk enhancers, USPSTF screening, initial labs, statin algorithm, TG management, pimp answers, case scenarios, and summary grid) wired to the 2026 PREVENT calculator. ASCVD/PCE references kept only where the historical 2018 comparison is intentional.
"Choose intensity by 2026 thresholds" decision matrix, expanded the algorithm step from a single sentence into a 3-row table mapping high / moderate / lifestyle-only to specific 2026 indications and default doses, plus "start at indicated intensity, don't titrate up" (CTT 22%/39 mg/dL framing) and "modify drug choice for special populations" (Asian rosuva 5 mg, eGFR <30 rosuva max 10, HIV on PI, transplant on cyclosporine, pregnancy, frail elderly).
Atorvastatin 40 vs 80 mg callout, new collapsible in the Medications tab covering 8 scenarios (ACS/post-MI → 80 with PROVE-IT/MIRACL, very-high-risk ASCVD → 80, not at goal at 4-12 wk → escalate, HeFH high baseline → 80, primary prev PREVENT ≥10% → 40, stable CAD → 40, elderly → 40, drug-interaction risk → 40 or switch to rosuva), plus dose-response flattening explanation and rosuva 20 vs 40 parallel.
Lipid topic collapsibles, converted "Two paths to LDL <55" decision tree, "Risk-Enhancing Factors", and "Lifestyle Interventions" tables to <details> blocks for visual density. Default closed; click ▶ to expand. Search index still finds them via textContent.
2026 framework consistency fixes, Case 1 relabeled from old PCE "borderline 5-7.5%" to PREVENT "intermediate 5-<10%" (with numeric LDL <100 goal); fasting/non-fasting alert updated to reference 2026 guideline; lipid panel row + DM row updated to say "PREVENT calculator inputs" / "regardless of PREVENT score"; TG management row calc-link relabeled from "ASCVD" to "PREVENT".
Layout fix: double scrollbar, body locked to viewport so only the main content scrolls; sidebar and topbar stay fixed.
Outpatient Diabetes refinements, SU row expanded with "why not first-line" rationale; comorbidity-driven drug-selection table clarified add-on vs replace metformin; T1/T2 abbreviations expanded to T1DM/T2DM in screening tables.
6 new lipid pearls framed as attending-on-rounds pimps: gemfibrozil + statin rhabdo (cerivastatin withdrawal), atorva 80 + ezetimibe escalation logic (IMPROVE-IT), SAMSON nocebo on statin "intolerance", Vascepa pure EPA vs OTC fish oil (REDUCE-IT vs STRENGTH), HeFH workup on LDL ≥190 + premature family CAD, Lp(a) once-per-lifetime + 2026 very-high-risk classification. Library now at 718.
NEW TOPIC: Outpatient Hypertension Management, 8-tab view covering ACC/AHA 2017 staging, workup with the lab "what changes management" depth (BMP, lipids, A1c, TSH, UACR, ECG, echo all with eGFR/A1c/TSH cutoffs and concrete decision points), drug selection by compelling indication, comprehensive Resistant HTN evaluation, and Antihypertensives in CKD & AKI section (atenolol/nadolol/sotalol AVOID list, RAAS hold list during AKI, IV options). Wired into Cardiology and Ambulatory rotation pages plus search index.
NEW CALCULATOR: ASCVD 10-Year Risk, full ACC/AHA Pooled Cohort Equation with all four race/sex coefficient sets (white men/women, AA men/women). Replaced the previous broken stub. Returns risk %, category (Low/Borderline/Intermediate/High), and exact statin + antihypertensive recommendation. Linked from every "ASCVD risk" mention site-wide via calc-link spans.
ADHF: Diuretic Escalation Ladder, 7-step escalation with acetazolamide (ADVOR 2022, 46% more decongestion), SGLT2i (EMPULSE/EMPAG-HF 2022), tolvaptan (EVEREST 2007), hypertonic saline (SMAC-HF 2011), plus the albumin + furosemide sandwich and sequential nephron blockade with mechanism explanations. Step 0 reversible-causes checklist (NSAIDs, hypotension, gut edema, RAS, hypothyroid, hypoalbuminemia) and red "what NOT to do" alerts (renal-dose dopamine ROSE-HF 2013, nesiritide ASCEND-HF 2011).
HF Medications: 4 new acute agents added to the Acute Agents table, chlorothiazide IV (Diuril), acetazolamide (Diamox + ADVOR cite), tolvaptan (Samsca + EVEREST cite), norepinephrine (SOAP II 2010 cite), IV ferric carboxymaltose (AFFIRM-AHF 2020 cite). Added "Meds to Come OFF at Admission" table (NSAIDs, non-DHP CCBs, TZDs, saxagliptin, gabapentinoids, high-dose steroids, class IC anti-arrhythmics, excess IVF) and red "Cardiogenic shock exception" callout listing exactly which GDMT drugs hold/start/continue and the resumption order.
Post-Cardiac Arrest: Secondary Prevention ICD & Disposition, new section in the Management tab citing AVID 1997 / CIDS 2000 / CASH 2000. When ICD IS indicated, when it's NOT (reversible causes including post-MI revasc, electrolytes, drug-induced QT, commotio cordis), timing rules with DINAMIT 2004 / IRIS 2009, and a Before-Discharge Checklist with VEST 2018 LifeVest bridge option. Cross-linked from the ACLS view's ROSC checklist.
Pneumothorax: Detailed Causes, full differential by category (primary spontaneous, secondary obstructive/infectious/cystic-bullous/ILD/connective tissue/special, traumatic, iatrogenic) with imaging and demographic clues plus a high-yield clue patterns alert (catamenial right-sided around menses, LAM with renal AMLs, BHD with skin/renal findings, HIV bilateral PTX).
Mech Vent Guide: Oxygen Dissociation Curve, new 40-50-60 / 70-80-90 rule section with the "SpO2 minus 30 ≈ PaO2" bedside shortcut, the knee at SpO2 90 / PaO2 60, curve shifts (CADET-face-Right mnemonic), and the two pulse-ox traps (CO poisoning needs co-oximetry, methemoglobinemia stuck at ~85% needs methylene blue).
RSI: Best Used For, added a "Best Used For" column to the Induction Agents comparison (etomidate for stable / head injury, ketamine for asthma / sepsis / awake intubation, propofol for status epilepticus / stable elective, plus a midazolam row) and a "Best Used For" row to the Paralytic comparison. New "Quick which agent decision rules" alert with per-agent rationale for 7 common scenarios.
HTN Outpatient: Why BBs aren't first-line, new collapsible explaining the central aortic vs brachial pressure mismatch (CAFE 2006 / ASCOT-BPLA 2005), other BB disadvantages, and an 11-row "When BBs ARE indicated" table covering HFrEF, post-MI, AFib rate control, stable angina, aortic dissection, thyrotoxicosis, pregnancy (labetalol), migraine, essential tremor, pheochromocytoma (after alpha-block), resistant HTN.
Pearl-of-the-Day banner now filters to ~270 priority-1/priority-2 curated pearls (not all 712), and rotation interval scales with pearl length (10s short pearls to 45s long pearls so residents can finish reading). Backfilled priority tags across 4 batches in the library.
Search engine: every word findable, removed 25,000-char section truncation (entire section content now indexed), lowered body-match threshold so single mentions surface (was requiring 5+ hits), stripped HTML markup from pearl indexing to prevent <strong>-tag false positives. <details> collapsibles still indexed because textContent ignores display state.
3 new pearls: albumin + furosemide sandwich (Nephrology · Diuretic Resistance), sequential nephron blockade (Nephrology · Diuretic Resistance), oxygen dissociation rule of thumb (Pulmonology · ABG). Library at 712 entries.
Medical accuracy fixes: BB initiation timing in ADHF moved from Day 1 to Day 3-5 (resolves contradiction with pimp answer), empagliflozin HF dose corrected to 10 mg only (was "10-25 mg"), PARADIGM-HF endpoint reworded to composite (CV death + HF hosp 20% RRR, not death alone), GDMT four-pillars table SGLT2i row completed (was missing 2 cells), metolazone dose range standardized to 2.5-10 mg, milrinone t½ wording disambiguated.
Main search engine now indexes every word in all 702 clinical pearls, pearl hits appear directly in site-wide results and deep-link into the Pearls Library with the query pre-applied
Expanded empiric sepsis antibiotic side-effect tables with main side effects bolded and ordered by clinical importance: meropenem (VPA interaction + seizure risk factors), cefepime (cefepime-induced neurotoxicity with NCSE + EEG findings), pip-tazo (AKI with vanc, false-positive galactomannan, hypokalemia mechanism), vancomycin (flushing syndrome, formerly "Red Man"), linezolid (serotonin syndrome + optic neuritis), metronidazole (disulfiram + cerebellar syndrome MRI findings)
Added 3 new clinical pearls: PEth (alcohol biomarker of choice in transplant evaluation), carbapenem–valproate interaction (breakthrough seizures/SE, bridge to levetiracetam), hypothermic resuscitation (warmed NS over LR, cold liver cannot clear lactate)
Major SEO pass: fixed 52 navigation anchors from javascript:void(0) → real /path hrefs, unlocking 273 previously-uncrawlable URLs for Googlebot discovery. Dashboard link canonicalized to / to prevent duplicate-content issues
Refreshed Clinical Pearls Library meta description with keyword expansion across 12 rotations for SEO
Clinical pearls library refined, 700 curated high-yield pearls across 15 rotations, each rewritten in the site's actionable bedside tone
About page polish: version bump, build date and "Last updated" timestamp refresh
v4.6 - April 13, 2026
SSC 2026 accuracy audit: corrected hydrocortisone timing (removed erroneous "4-hour" threshold - guideline specifies "ongoing vasopressor requirement," not a specific wait time; 4h was trial enrollment criteria from ADRENAL/APROCCHSS)
Fixed albumin recommendation: SSC 2026 reversed from 2021 - now suggests crystalloids alone over crystalloids + albumin for initial resuscitation (exceptions: large crystalloid volumes, cirrhosis)
Fixed norepinephrine recommendation strength: SSC 2026 downgraded NE from strong ("recommend") to conditional ("suggest") - still first-line but weaker certainty
Added MAP 60-65 mmHg target for adults ≥ 65 years (new SSC 2026 recommendation, previously one-size-fits-all ≥ 65)
Added prolonged beta-lactam infusion: SSC 2026 recommends (strong, moderate certainty) prolonged infusion for maintenance over bolus dosing
Added dynamic fluid responsiveness measures (PLR, SVV, PPV) - SSC 2026 suggests over physical exam or static measures alone
Added blood purification: SSC 2026 suggests against hemoperfusion, high-dose hemofiltration, and plasma exchange
Added post-30 mL/kg fluid strategy: SSC 2026 suggests either liberal or restrictive approach based on individual factors
Updated SSC 2026 comparison topic with 3 new rows (beta-lactam infusion, fluid responsiveness, blood purification) and 4 new cards in New Topics section
Corrected steroid language across 15+ locations site-wide (sepsis, pressors, corticosteroids, SSC comparison, changelog, loading tips, trial cards)
Corrected steroid attribution: the reversal of the 2016 anti-steroid stance happened in 2021, not 2026. 2026 maintained the 2021 position. Replaced "7 Biggest Changes" card #4 (steroids) with prolonged beta-lactam infusion (an actual new 2026 change)
v4.5 - March 15, 2026
Expanded 13 thin clinical topics with new pimp questions, trial citations, clinical scenarios, comparison tables, and alert boxes: Small Bowel Obstruction, Transfusion Reactions, Brain Death, Headache/Migraine, Hypernatremia, RTA, Alcoholic Hepatitis, Necrotizing Fasciitis, Stable Angina/Chronic CAD, Tuberculosis, Trauma Primary/Secondary Survey, Family Meeting Framework, Prognostication Tools
Fixed 7 duplicate element IDs across Corticosteroids, Cardiogenic Shock, Inpatient Insulin, Thyroid Storm, Hemoptysis, IBD, and Acute Abdomen views (renamed conflicting section-anchors)
Fixed 19 views with orphaned content floating outside section-anchors (pancytopenia, mitral regurgitation, falls, hypertensive emergency, C. diff, hyponatremia, HIV, GBS, myasthenic crisis, TLS, transfusion, HIT, neutropenic fever, hypercalcemia, gout, preventive care, hyperkalemia, mesenteric ischemia, and more)
Fixed 14 unbalanced views with missing closing div tags
Improved search engine: scaled bodyCount threshold prevents generic views from appearing in short-query searches; search now scrolls directly to highlighted text match
New topic: Corticosteroids (Endocrinology) with full steroid equivalency table, glucocorticoid vs mineralocorticoid potency comparison, clinical use guide (15 scenarios), side effects by system, tapering protocols, and 6 pimp questions
Updated homepage tagline: "Know Why, Not Just What" / "The why behind every decision"
Added relative adrenal insufficiency (CIRCI) to Corticosteroids clinical use table with SSC 2026 guideline (steroids suggested for refractory septic shock)
Added dexamethasone vs hydrocortisone alert to Adrenal Crisis diagnosis section (dex does not interfere with cosyntropin stim test)
Improved search engine: fuzzy typo tolerance now applies to full-text search (not just curated entries), section text index expanded from 2000 to 5000 chars
Updated steroid equivalency table in Pain Management & Conversions: corrected mineralocorticoid potencies, added trial stickers, and linked to full Corticosteroids topic
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Removed 3 more orphaned monitoring blocks: HF Monitoring inside HCM, Mesenteric Ischemia Monitoring inside PFT, Pleural Effusion Monitoring inside OSA
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v4.1, April 1, 2026
Full-text search engine: every word on the site is now searchable, not just topic titles. Lazy-built index covers all 240 views and 1,300+ sections
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v3.8, March 30, 2026
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Last updated: August 12, 2026 at 7:38 PM
Hematology
Immune Thrombocytopenia (ITP)
Antibody-mediated platelet destruction. Diagnosis of exclusion. Most adults need treatment only if platelets < 30K or bleeding.
🔍 Overview
Overview
ITP is an autoimmune condition where IgG autoantibodies target platelet surface glycoproteins (GPIIb/IIIa, GPIb/IX), leading to splenic phagocytosis and accelerated platelet destruction. It is a diagnosis of exclusion -there is no confirmatory test. Incidence: ~3-4/100,000 adults/year. Primary ITP (80%) has no identifiable cause. Secondary ITP (20%) is associated with SLE, HIV, HCV, H. pylori, CLL, or medications (heparin → HIT, not ITP). Key principle: treat the patient, not the number. Many patients tolerate platelets of 20-30K without significant bleeding.
🧪 Workup
Workup
CBC with peripheral smear -isolated thrombocytopenia with large platelets (young, reactive). All other cell lines normal. If pancytopenia → think MDS, aplastic anemia, infiltrative process.
Peripheral smear -must review. Rules out pseudothrombocytopenia (platelet clumping from EDTA -redraw in citrate tube), schistocytes (TTP/HUS), blasts (leukemia), leukoerythroblastic picture (marrow infiltration).
HIV, HCV -required in all new ITP (secondary causes that change management)
H. pylori testing -stool antigen or breath test. Eradication can improve platelet count.
Direct Coombs (DAT) -Evans syndrome = autoimmune hemolytic anemia + ITP. If DAT positive → treat as Evans.
Immunoglobulins (quantitative Ig) -CVID can present with ITP
ANA -if SLE suspected (young woman with ITP)
Coags (PT/INR, aPTT) -should be normal. If abnormal → think DIC, liver disease, factor deficiency.
Bone marrow biopsy -NOT routine for typical ITP. Indicated if: age > 60 (rule out MDS), atypical features (other cytopenias, splenomegaly, lymphadenopathy), or refractory to first-line therapy.
⚠️ Rule out pseudothrombocytopenia FIRST (before working up any isolated low platelet count). It is a lab artifact, not a real low count: EDTA in the lavender CBC tube chelates calcium, exposing a cryptic epitope on platelet GPIIb/IIIa that naturally occurring antibodies (usually IgG) bind, clumping the platelets in vitro. The analyzer counts each clump as one particle (or skips it), so it reports a falsely low number. The patient’s true count is normal and they are not bleeding, the tip-off is severe “thrombocytopenia” with no clinical correlate.
Confirm on the peripheral smear (the diagnostic manual step), platelet clumps, classically at the feathered edge. Seeing clumps tells you the automated count is spurious.
Can you just do a manual count? Only on a non-clumped specimen. A manual hemocytometer count run on the same clumped EDTA tube is also falsely low, because aggregated platelets cannot be counted as singles by any method, automated or manual. The clumps have to be prevented first.
Get an accurate count by removing the clumping: redraw in sodium citrate (blue top) and multiply the result by 1.1 to correct for the citrate dilution; or use heparin (green top); and/or warm the sample to 37°C and run promptly (some cases are cold-dependent). Then either automated or manual counting is reliable.
Why it matters: mistaking pseudothrombocytopenia for true thrombocytopenia leads to unnecessary platelet transfusions, steroids, marrow biopsies, and held anticoagulation. The fix is changing the tube, not treating the patient.
🚨 Management
Management
Observation only if platelets ≥ 30K and no bleeding and no upcoming procedures -most patients don't need treatment. ASH Guidelines, 2019
First-line -Corticosteroids:
Dexamethasone 40 mg PO daily × 4 days -preferred by many experts. Faster response, shorter course. Can repeat q2-4 weeks × 3-4 cycles. Wei, 2016
Prednisone 1 mg/kg daily × 2-4 weeks → taper. Classic approach. Response in 70-80% but relapse rate ~60-80% after taper.
First-line adjunct -IVIG 1g/kg × 1-2 days: for active bleeding or platelets < 10K or pre-procedure. Fastest response (24-48h) but transient (2-4 weeks). Fc receptor blockade → reduced splenic phagocytosis.
Anti-D (WinRho) 50-75 mcg/kg IV: only for Rh-positive, non-splenectomized patients. Causes mild extravascular hemolysis that "distracts" the spleen. FDA black box: rare fatal intravascular hemolysis.
Second-line -TPO receptor agonists:Eltrombopag 50 mg PO daily or Romiplostim 1-10 mcg/kg SQ weekly. Stimulate megakaryopoiesis. ~80% response. Maintenance therapy -platelets drop when stopped. RAISE, 2011; EXTEND
Second-line -Rituximab 375 mg/m² weekly × 4: ~60% initial response but only ~20-30% sustained at 5 years. Best in younger patients with short disease duration.
Second-line -Fostamatinib (SYK inhibitor): 100-150 mg BID PO. For refractory ITP. FIT, 2018
Third-line -Splenectomy: ~65% long-term remission. Defer at least 12-24 months (spontaneous remission possible). Requires pre-op vaccines (pneumococcal, meningococcal, Hib) ≥ 2 weeks before surgery.
Emergency bleeding: Platelets + IVIG + methylprednisolone 1g IV + aminocaproic acid (antifibrinolytic). Consider emergent splenectomy if refractory.
💊 Medications
Medications
Drug
Dose
Route
Notes
Dexamethasone
40 mg daily × 4 days
PO
Preferred first-line. Can repeat q2-4 wk. Wei, 2016
Prednisone
1 mg/kg × 2-4 wk → taper
PO
Alternative first-line. 70-80% response. High relapse on taper.
IVIG
1 g/kg × 1-2 days
IV
Fastest response (24-48h). For bleeding or plt < 10K. Transient. Monitor for infusion reactions, aseptic meningitis.
Eltrombopag
50 mg daily (titrate 25-75)
PO
TPO-RA. Response in 1-2 wk. Monitor LFTs. Take on empty stomach (no dairy/Ca). RAISE, 2011
Romiplostim
1-10 mcg/kg weekly
SQ
TPO-RA. Titrate by platelet response. Risk of marrow reticulin fibrosis (reversible).
SYK inhibitor for refractory ITP. SE: diarrhea, HTN, LFT elevation. FIT, 2018
Aminocaproic acid
4-5g load → 1g/hr
IV/PO
Antifibrinolytic for emergency bleeding. Adjunct to platelets.
🏥 Rounds
Sample Presentation
Mrs. Patel is a 34-year-old woman presenting with 3 days of spontaneous bruising and petechiae on bilateral lower extremities. No mucosal bleeding, no epistaxis, no hemoptysis, no melena. No recent illness or new medications. No joint pains or rash. VS stable. Exam: scattered petechiae on shins, no splenomegaly, no lymphadenopathy. Labs: platelets 8K (previously normal 6 months ago), Hgb 13.2, WBC 6.8, peripheral smear shows large platelets with no schistocytes/blasts. PT/INR normal. HIV negative, HCV negative, H. pylori stool antigen negative. DAT negative.
Key Points: Isolated thrombocytopenia with large platelets and otherwise normal CBC + smear = classic ITP. Plt < 10K with mucosal bleeding risk → start IVIG 1g/kg + dexamethasone 40 mg × 4 days. No need for bone marrow biopsy in a young patient with typical presentation.
Pimp Questions
❓ What is the platelet threshold for treatment in ITP?
Platelets < 30K or any clinically significant bleeding, regardless of count. Treat the patient, not the number. Many patients tolerate 20-30K without bleeding. ASH Guidelines, 2019
❓ What must you always check on the peripheral smear before diagnosing ITP?
Rule out pseudothrombocytopenia (EDTA-induced platelet clumping -redraw in citrate tube), schistocytes (TTP/HUS/DIC), blasts (leukemia), and leukoerythroblastic picture (marrow infiltration). ITP should show large platelets and nothing else abnormal.
❓ When do you give IVIG vs steroids alone in ITP?
IVIG 1 g/kg for: active bleeding, platelets < 10K, or pre-procedure urgent platelet rise needed. IVIG works in 24-48 hours (fastest). Steroids alone are adequate for stable patients with plt 10-30K and no active bleeding. IVIG effect is transient (2-4 weeks).
❓ What is Evans syndrome?
Evans syndrome = autoimmune hemolytic anemia (AIHA) + ITP. Positive direct Coombs test + thrombocytopenia. More aggressive course than ITP alone. Often associated with SLE or lymphoproliferative disorders. Treatment: steroids, rituximab. Check DAT in all ITP patients.
❓ What vaccines are required before splenectomy for ITP?
Pneumococcal (PCV20 or PCV15 + PPSV23), meningococcal (MenACWY + MenB), and Haemophilus influenzae type b (Hib). Give ≥ 2 weeks before surgery. Post-splenectomy: lifelong risk of overwhelming post-splenectomy infection (OPSI) from encapsulated organisms.
❓ What are TPO receptor agonists and when do you use them?
Eltrombopag (oral, daily) and romiplostim (SQ, weekly) stimulate megakaryopoiesis via the thrombopoietin receptor. Second-line for chronic ITP failing steroids. ~80% response rate. Maintenance therapy -platelets drop when stopped. Monitor LFTs (eltrombopag) and for reticulin fibrosis (both). RAISE, 2011
❓ When do you perform a bone marrow biopsy in ITP?
NOT routine. Indications: (1) age > 60 (rule out MDS), (2) atypical features (other cytopenias, splenomegaly, lymphadenopathy, abnormal smear), (3) refractory to first-line therapy, (4) before splenectomy (some centers). In typical young-adult ITP with isolated thrombocytopenia, diagnosis is clinical.
❓ What is "wet purpura" and why is it important?
Wet purpura = hemorrhagic bullae (blood blisters) in the oral mucosa. It indicates a higher risk of serious hemorrhage compared to dry purpura (skin-only petechiae/ecchymoses). Wet purpura with plt < 10K is an indication for urgent treatment with IVIG + high-dose steroids.
Clinical Examples
📋 Case 1, Newly Diagnosed ITP with Severe Thrombocytopenia
Patient: 28F with petechiae on legs, gum bleeding, and menorrhagia × 1 week. Platelets 8K. WBC and Hgb normal. Smear: large platelets, no schistocytes. No splenomegaly. No meds.
Key findings: Isolated thrombocytopenia in a young woman with no other cytopenias and normal smear = classic ITP. Large platelets = increased marrow production (compensatory). No schistocytes rules out TTP/HUS.
Management:
Dexamethasone 40 mg daily × 4 days (preferred over prednisone taper, faster response, shorter course)
IVIG 1 g/kg × 1-2 days if wet purpura or active mucosal bleeding (raises platelets within 24-48h)
Hold anticoagulants, avoid NSAIDs, IM injections, contact sports
Check HIV, HCV, H. pylori (treatable causes of secondary ITP)
Teaching point: ITP is a diagnosis of exclusion, there is no confirmatory test. The goal is NOT a normal platelet count; it's a safe count (≥ 30K in most patients). Overtreating asymptomatic mild ITP causes more harm than the disease.
📋 Case 2, Chronic Refractory ITP
Patient: 52F with ITP × 3 years. Failed steroids (relapsed after taper × 3), failed rituximab. Currently on romiplostim 5 mcg/kg weekly, platelets fluctuate 15-40K. Now needs hip replacement. Surgeon wants platelets > 50K.
Key findings: Chronic refractory ITP requiring pre-surgical platelet optimization. Bone marrow biopsy showed megakaryocytic hyperplasia (appropriate for ITP). No MDS features.
Management:
Increase romiplostim to 8-10 mcg/kg weekly (titrate to target > 50K for surgery)
Add IVIG 1 g/kg 1-2 days pre-op for rapid temporary boost
Platelet transfusion available in OR (transfuse only for active surgical bleeding)
Consider eltrombopag 50-75 mg daily as add-on or alternative TPO-RA
TXA 1g IV pre-op + 1g q8h × 3 days post-op (antifibrinolytic, reduces surgical bleeding)
Teaching point: TPO receptor agonists (romiplostim, eltrombopag) are the backbone of chronic ITP management. They work in ~80% of patients but require ongoing therapy, platelets drop when stopped. For surgery, combine TPO-RA dose escalation + IVIG for reliable platelet elevation.
📋 Case 3, ITP with Life-Threatening Intracranial Hemorrhage
Patient: 65M with known ITP (non-compliant with eltrombopag). Presents with sudden severe headache, vomiting, right hemiplegia. CT head: left basal ganglia hemorrhage with midline shift. Platelets 3K.
Key findings: ICH in the setting of severe thrombocytopenia, life-threatening emergency. Mortality of ICH with plt < 10K approaches 50%. This is one of the few situations where platelet transfusion is indicated in ITP.
Management:
Platelet transfusion: 2-3 adult doses STAT (even though destroyed rapidly, provides temporary hemostasis)
IVIG 1 g/kg IV STAT (raises endogenous platelets within 24-48h by blocking Fc receptors on splenic macrophages)
Methylprednisolone 1g IV daily × 3 days
TXA 1g IV (antifibrinolytic, stabilizes existing clot)
Emergent neurosurgery consult for possible decompressive craniotomy
Teaching point: ICH is the most feared complication of ITP (< 1% but devastating). In this scenario, transfuse platelets despite ITP, the immediate hemostatic need outweighs the short platelet lifespan. Combine with IVIG and steroids for sustained response.
Monitoring
Platelet count -q1-2 days during active treatment; weekly during titration; monthly once stable. Goal: ≥ 30K (not "normal").
Pseudothrombocytopenia before anything else.EDTA in the lavender CBC tube chelates calcium, exposing an epitope on platelet GPIIb/IIIa, and the platelets clump, so the analyzer counts them as one. Repeat in a citrate or heparin tube and look at the smear for clumps. Working up an artifact is the commonest wasted workup in hematology.
It Is a Diagnosis of Exclusion
Isolated thrombocytopenia with a normal white count, normal hemoglobin and an otherwise normal smear.Exclude the alternatives: drugs (heparin, quinine, sulfonamides, vancomycin, linezolid), infection (HIV, HCV, H. pylori, EBV, CMV), liver disease with splenic sequestration, lymphoproliferative disorders, lupus and antiphospholipid syndrome, TTP and DIC. An antiplatelet antibody test is not useful and should not be ordered.
Treat the Bleeding Risk, Not the Number
Most adults need treatment only for platelets below 30,000 or for bleeding.Above 30,000 without bleeding, observe: the risk of the treatment exceeds the risk of the count. Wet purpura, mucosal or GI bleeding, is far more concerning than petechiae and is what should escalate management.
First Line Is a Steroid
Dexamethasone 40 mg daily for 4 days is preferred, repeatable every 2 to 4 weeks, with faster responses and less cumulative toxicity than a long prednisone taper. Prednisone 1 mg/kg for 2 to 4 weeks then taper is the alternative, with 70 to 80% responding but a high relapse rate on the taper. Do not keep a patient on chronic steroids to hold a count: move to a second-line agent instead.
IVIG for Speed
1 g/kg for 1 to 2 days, giving a response in 24 to 48 h.Use it when there is bleeding, before an urgent procedure, or with a platelet count below 10,000, because steroids take days. The effect is transient, so it buys time rather than treating the disease, and it is given alongside a steroid rather than instead of one. Anti-D is an alternative in Rh-positive, non-splenectomized patients.
Second Line Has Genuinely Changed
Thrombopoietin receptor agonists (eltrombopag, romiplostim) and rituximab have largely displaced early splenectomy.TPO agonists work in most patients but usually need to be continued, and eltrombopag has to be separated from calcium and food. Splenectomy still gives the highest durable remission rate but is now deferred at least 12 months, and requires encapsulated-organism vaccination beforehand.
Transfuse Platelets Only for Serious Bleeding
Transfused platelets are destroyed by the same antibody within hours, so a routine transfusion for a low number achieves nothing. Reserve them for life-threatening bleeding, given with IVIG, where the goal is a brief hemostatic window rather than a corrected count.
Special Situations
Pregnancy: distinguish ITP from gestational thrombocytopenia (mild, third trimester, no fetal effect) and from preeclampsia or HELLP; steroids and IVIG are the safe options and the platelet count needed depends on the delivery mode and the anesthetic plan. Test for HIV and HCV in every adult, because both cause ITP and both are treatable at the cause. Secondary ITP from lupus or CLL is treated by treating the underlying disease.
Life-threatening complications of malignancy requiring immediate recognition: SVC syndrome, cord compression, brain mets, hyperviscosity, and tumor lysis.
🔍 Overview
Overview
Oncologic emergencies are complications of cancer or its treatment that require immediate intervention to prevent death or irreversible organ damage. The key emergencies: (1) Superior vena cava (SVC) syndrome -obstruction of SVC, usually by lung cancer or lymphoma. (2) Malignant spinal cord compression (MSCC) -epidural metastasis compressing the cord. (3) Brain metastases with herniation -elevated ICP. (4) Hyperviscosity syndrome -Waldenström macroglobulinemia or multiple myeloma. (5) Tumor lysis syndrome -covered separately. (6) Febrile neutropenia -covered separately. (7) Malignant pericardial effusion/tamponade. The intern's role: recognize the pattern, start dexamethasone, and call oncology/radiation/surgery.
🧪 Workup
Workup
SVC syndrome: CT chest with contrast (confirms obstruction + identifies cause). CXR may show widened mediastinum. Tissue diagnosis before radiation if patient is stable.
Cord compression:MRI entire spine with contrast -gold standard. Order STAT. Must image ENTIRE spine (multiple levels in 10-38%). Check post-void residual (early bladder dysfunction).
Brain mets: MRI brain with contrast. CT if MRI unavailable. Fundoscopy for papilledema. Assess for midline shift and herniation signs.
SVC syndrome: Elevate HOB. Dexamethasone 10 mg IV (if lymphoma suspected -exquisitely steroid-sensitive). Radiation therapy for NSCLC. Endovascular stenting for rapid relief. Anticoagulation if thrombus. Do NOT delay treatment for tissue diagnosis if severely symptomatic.
Cord compression:Dexamethasone 10 mg IV STAT → 4 mg IV q6h. Must give within 24h of symptom onset -neurologic outcome correlates with pre-treatment function. Radiation (most common treatment). Surgery if: unknown primary (need tissue), radioresistant tumor, mechanical instability, or single-level disease with good prognosis. Patchell, Lancet 2005
Brain mets: Dexamethasone 10 mg IV → 4 mg q6h (reduce edema). Anticonvulsants only if seizure has occurred (not prophylactic). Surgery for single resectable met with controlled primary. SRS (stereotactic radiosurgery) for ≤ 4 mets. WBRT for diffuse mets or poor prognosis.
Hyperviscosity:Emergent plasmapheresis. Avoid pRBC transfusion before pheresis (increases viscosity further). Start definitive chemotherapy after pheresis.
Tamponade: Pericardiocentesis (echo-guided). Pericardial window if recurrent. Intrapericardial chemotherapy or sclerotherapy for malignant effusions.
💊 Medications
Medications
Drug
Dose
Route
Notes
Dexamethasone
10 mg IV bolus → 4 mg q6h
IV
For cord compression, brain mets, SVC (lymphoma). Reduces vasogenic edema. Start immediately -do not wait for imaging.
Levetiracetam
500-1000 mg BID
IV/PO
If seizure with brain mets. NOT for prophylaxis in brain mets without seizure.
Mannitol
0.5-1 g/kg IV
IV
Impending herniation from brain mets. Osmotic diuresis reduces ICP. Bridge to dexamethasone effect.
Hypertonic saline 3%
150-250 mL bolus
IV
Alternative to mannitol for acute ICP crisis.
Radiation therapy
Per radiation oncology
-
Mainstay for cord compression, SVC (solid tumors), brain mets (WBRT/SRS).
Pericardial effusion reaccumulation -repeat echo at 24-48h post-pericardiocentesis. 40-70% recurrence rate with malignant effusions.
Respiratory status -SVC syndrome patients at risk for airway compromise. Keep intubation equipment at bedside.
🏥 Rounds
Pimp Questions
❓ What is the most important prognostic factor in malignant cord compression?
Pre-treatment neurologic status. Patients who are ambulatory at diagnosis have ~80% chance of remaining ambulatory. Patients who are paraplegic at diagnosis have < 10% chance of regaining ambulation. This is why immediate dexamethasone and urgent imaging matter -every hour counts. Patchell, 2005
❓ Why do you NOT give prophylactic anticonvulsants for brain metastases?
Multiple RCTs show no benefit from prophylactic AEDs in brain mets without prior seizure, AND significant side effects (rash, drug interactions with chemo, sedation). AAN guidelines explicitly recommend against prophylaxis. Treat only if seizure has occurred. Levetiracetam preferred (fewer drug interactions than phenytoin).
❓ Why should you avoid pRBC transfusion before plasmapheresis in hyperviscosity?
Transfusing pRBCs increases blood viscosity further by raising hematocrit. In a patient already symptomatic from hyperviscosity (IgM paraprotein causing sludging), this can precipitate stroke, retinal vein occlusion, or cardiac failure. Do plasmapheresis FIRST, then transfuse if needed afterward.
❓ Name the classic triad of SVC syndrome.
Facial/upper extremity edema + dyspnea + distended neck/chest wall veins. Worse when leaning forward or lying flat. Pemberton sign: facial plethora + cyanosis when arms raised above head. Most common cause: lung cancer (especially right-sided). Second: lymphoma (more steroid-responsive).
❓ What imaging do you order for suspected cord compression and why must you image the entire spine?
MRI entire spine with gadolinium contrast -gold standard. Must image the ENTIRE spine because 10-38% of patients have multiple levels of compression. Treating only the symptomatic level while missing another will lead to treatment failure. CT myelography is an alternative if MRI contraindicated.
❓ When is surgery preferred over radiation for cord compression?
Surgery (decompressive laminectomy ± stabilization) is preferred when: (1) unknown primary (need tissue for diagnosis), (2) radioresistant tumor (renal cell, melanoma), (3) mechanical spinal instability, (4) single level of disease with good overall prognosis, (5) progression during or after radiation.Patchell, 2005 showed surgery + RT was superior to RT alone for single-level compression.
Sample Presentation
Mr. Johnson is a 62-year-old man with known Stage IV NSCLC (right upper lobe, 3 cycles of pembrolizumab) presenting with 2 days of progressive lower extremity weakness and urinary retention. Exam: 4/5 hip flexors bilateral, absent ankle reflexes, T10 sensory level, post-void residual 400 mL. No saddle anesthesia. VS stable. MRI spine: T9-T10 epidural mass with cord compression.
Key Points: This is MSCC -give dexamethasone 10 mg IV STAT, consult radiation oncology AND spine surgery. Motor function at presentation is the strongest predictor of outcome. Ambulatory at diagnosis → 80% remain ambulatory. Non-ambulatory → only 10-20% regain walking.
📋 Summary
Summary
The Ones That Cannot Wait
Spinal cord compression, superior vena cava syndrome with airway compromise, raised intracranial pressure from brain metastases, tumor lysis syndrome, hypercalcemia of malignancy, neutropenic fever, hyperviscosity and leukostasis.Several present before the cancer is known, so the absence of an oncology history is not reassuring.
Cord Compression: Steroids Before Imaging
Back pain precedes neurologic deficit by weeks in most patients, and it is the point at which the outcome is still recoverable.Give dexamethasone 10 mg IV immediately, then 4 mg q6h, and get an urgent MRI of the whole spine (whole spine, because multilevel disease is common). Function at the time of treatment is the strongest predictor of function afterward, so a patient who can still walk is an emergency, not a next-morning MRI.
SVC Syndrome Is Rarely a True Airway Emergency
Facial and upper limb swelling, distended neck and chest veins, orthopnea.Get tissue before treating when the patient is stable, because steroids or radiation can make a lymphoma unbiopsiable and lymphoma is curable. Stridor, airway compromise or depressed consciousness change that: those need immediate intervention, endovascular stenting being the fastest option. Anticoagulate if there is associated thrombus.
Brain Metastases and Raised ICP
Dexamethasone reduces vasogenic edema and often improves symptoms within hours.Mannitol 0.5 to 1 g/kg or hypertonic saline for impending herniation, then urgent neurosurgical and radiation oncology input. Do not give prophylactic antiepileptics to a patient who has not had a seizure: they do not prevent the first seizure and add interactions and toxicity. Treat seizures that occur, with levetiracetam preferred.
Tumor Lysis Syndrome
High potassium, high phosphate, high uric acid and low calcium, with acute kidney injury.Prevent rather than treat: aggressive fluids plus allopurinol, and rasburicase for high-risk disease or an already raised uric acid (contraindicated in G6PD deficiency). Labs every 6 to 8 h during the first cycle.Do not correct asymptomatic hypocalcemia, because calcium-phosphate precipitation worsens the renal injury.
Hypercalcemia of Malignancy
Aggressive isotonic saline first, then a bisphosphonate (zoledronic acid), which takes 2 to 4 days to work, with calcitonin as the bridge for the first 48 h. Denosumab when renal function precludes a bisphosphonate.Avoid loop diuretics unless the patient is volume overloaded: that is old teaching, and diuresing a dehydrated patient worsens the calcium. It signals a poor prognosis, so it is also a prompt for a goals-of-care conversation.
Neutropenic Fever Is a One-Hour Antibiotic
A single temperature of 38.3°C, or 38.0°C sustained for an hour, with ANC below 500.Blood cultures then broad-spectrum antipseudomonal antibiotics within 1 hour, before imaging and before a source is identified. These patients cannot mount inflammation, so the usual localizing signs may be entirely absent and a benign examination does not mean a benign infection.
Hyperviscosity and Leukostasis
Bleeding, visual change and neurologic symptoms with a paraprotein (usually IgM in Waldenstrom) or an extreme white count.Paraprotein → plasmapheresis. Leukostasis → leukapheresis plus hydroxyurea and urgent cytoreduction.Do not transfuse red cells before the viscosity is lowered: raising the hematocrit worsens sludging and can precipitate stroke or infarction.
Simultaneous reduction of all three cell lines. Systematic approach: peripheral smear first, then bone marrow biopsy. Think production vs destruction.
🔍 Overview
Overview
Pancytopenia = anemia + leukopenia + thrombocytopenia. Not a diagnosis but a lab finding requiring systematic workup. Framework: decreased production (marrow failure: aplastic anemia, MDS, leukemia, myelofibrosis, infiltration by solid tumor, infection, medication) vs increased destruction/sequestration (hypersplenism, autoimmune, HLH, DIC). The peripheral smear is the single most important initial test -it guides the entire workup.
Supportive care: pRBC for Hgb < 7 (or < 8 symptomatic). Platelets if < 10K or bleeding. Neutropenic precautions if ANC < 500. G-CSF if severe neutropenia with infection.
💊 Medications
Medications
Drug
Dose
Route
Notes
Cyanocobalamin
1000 mcg IM daily × 7d
IM
B12 deficiency. Expect retic crisis at day 5-7. Monitor K⁺ (drops with new cell production).
Horse ATG (ATGAM)
40 mg/kg/day × 4 days
IV
Aplastic anemia immunosuppression. Give with steroids (serum sickness prophylaxis). Scheinberg, 2011
Cyclosporine
5-6 mg/kg/day divided BID
PO
With ATG for aplastic anemia. Target trough 200-400. Nephrotoxicity, HTN, tremor.
Eltrombopag
150 mg daily
PO
Added to ATG+CsA in aplastic anemia improves response. RACE, 2022
Azacitidine
75 mg/m² SQ × 7 days q28d
SQ
High-risk MDS. Delays AML transformation. AZA-001, 2009
Lenalidomide
10 mg daily × 21/28 days
PO
MDS with del(5q). 67% transfusion independence. VTE prophylaxis required.
Filgrastim (G-CSF)
5 mcg/kg SQ daily
SQ
Severe neutropenia with infection. Not for chronic use in MDS (may accelerate AML).
🏥 Rounds
Pimp Questions
❓ What does a "dry tap" on bone marrow aspiration suggest?
A dry tap means the aspirate needle is correctly positioned but no marrow can be drawn. This occurs when the marrow space is replaced by fibrosis (myelofibrosis), packed with tumor cells (metastatic carcinoma, hairy cell leukemia), or in rare cases of severely aplastic marrow. The key next step is a core biopsy, this provides a tissue architecture sample even when aspiration fails. Reticulin and trichrome stains on the core biopsy will confirm fibrosis. Always suspect myelofibrosis when you see teardrop cells on smear + dry tap + splenomegaly.
❓ How do you differentiate aplastic anemia from MDS?
This is one of the most challenging distinctions in hematology. Key differences: Aplastic anemia → hypocellular marrow with normal morphology, no dysplasia, no increased blasts, younger patients, often responds to immunosuppression. Hypoplastic MDS → hypocellular marrow BUT with dysplastic changes (pseudo-Pelger-Huet cells, ring sideroblasts), cytogenetic abnormalities (especially -7, +8, del20q), and may have increased blasts. Cytogenetics is the key differentiator: present in ~50% of MDS but normal in aplastic anemia. Some cases require serial monitoring because aplastic anemia can evolve into MDS over time.
❓ What is the single most important initial test in pancytopenia?
Peripheral blood smear. It guides the entire workup: blasts (leukemia), teardrops (myelofibrosis), schistocytes (TTP/DIC), megaloblastic changes (B12/folate), dysplastic cells (MDS), normal morphology (aplastic anemia, viral, drug-induced).
❓ How can B12 deficiency cause pancytopenia?
B12 is required for DNA synthesis. Deficiency causes ineffective hematopoiesis -cells are produced but destroyed before release (intramedullary hemolysis). All three cell lines affected. The marrow is actually hypercellular (not empty) -megaloblastic precursors are dying before maturation. This can mimic MDS.
❓ What is a "dry tap" on bone marrow aspiration and what does it suggest?
A dry tap = inability to aspirate marrow despite proper needle placement. Classic for myelofibrosis (marrow replaced by reticulin/collagen fibrosis). Also seen in hairy cell leukemia, metastatic carcinoma (packed marrow), and some cases of aplastic anemia. Core biopsy is essential when aspirate fails.
❓ What electrolyte must you monitor when starting B12 repletion?
Potassium. As new red blood cells are rapidly produced (reticulocyte crisis), potassium shifts intracellularly. This can cause severe hypokalemia -potentially fatal if not monitored and repleted. Also monitor phosphate and magnesium for the same reason.
❓ Name a non-hematologic cause of pancytopenia that is commonly missed.
Copper deficiency. Causes sideroblastic anemia + neutropenia ± thrombocytopenia. Mimics MDS on smear and marrow. Risk factors: gastric bypass surgery, zinc supplementation (zinc competes with copper absorption), malnutrition, TPN without copper. Serum copper and ceruloplasmin are low. Responds to copper supplementation.
Peripheral smear: Pancytopenia with normal morphology, no blasts, no dysplasia, no schistocytes.
Workup:
B12, folate, HIV, hepatitis panel, all normal
LDH and haptoglobin, normal (no hemolysis)
Flow cytometry, no PNH clone
Bone marrow biopsy: markedly hypocellular (< 10% cellularity), fat-predominant, no blasts, no fibrosis
Diagnosis: Severe aplastic anemia (SAA), meets criteria: ANC < 500, Plt < 20K, retic < 1% with hypocellular marrow.
Treatment: No matched sibling donor → started on horse ATG + cyclosporine + eltrombopag. Supportive care with irradiated, leukoreduced blood products. Neutropenic precautions.
📋 Case 2, Megaloblastic Anemia (B12 Deficiency)
Patient: 68M presenting with progressive fatigue, paresthesias in both feet, and unsteady gait over 6 months.
Diagnosis: Megaloblastic pancytopenia from B12 deficiency (pernicious anemia). No bone marrow biopsy needed, smear + B12 level diagnostic.
Treatment: IM cyanocobalamin 1000 mcg daily × 7 days → weekly × 4 → monthly for life. Reticulocyte crisis at day 5. Monitor K⁺ closely. Neuro symptoms may take months to improve.
📋 Case 3, Myelofibrosis
Patient: 72F presenting with early satiety, weight loss, night sweats, and progressive fatigue over 4 months.
Exam: Massive splenomegaly (palpable 8 cm below costal margin).
Bone marrow aspiration: dry tap, unable to aspirate despite multiple attempts
Core biopsy: extensive reticulin and collagen fibrosis, megakaryocyte atypia, osteosclerosis
JAK2 V617F mutation: positive
DIPSS-Plus risk score: intermediate-2
Diagnosis: Primary myelofibrosis (PMF). Dry tap + teardrop cells + leukoerythroblastic smear is the classic triad.
Treatment: Started ruxolitinib (JAK2 inhibitor) for symptom control and splenomegaly. Evaluated for allogeneic transplant given intermediate-2 risk.
Sample Presentation
Mrs. Chen is a 72-year-old woman referred for pancytopenia found on routine labs: Hgb 8.1, WBC 2.8 (ANC 900), platelets 78K. No B symptoms. No bleeding. No infections. Medications: metformin, lisinopril. Peripheral smear: macrocytosis, hypersegmented neutrophils, oval macrocytes. B12 level: 89 pg/mL (low). MMA elevated. Folate normal. Retic count 0.5%.
Key Points: Classic megaloblastic pancytopenia from B12 deficiency. Smear is diagnostic -hypersegmented neutrophils + oval macrocytes. Start IM B12 immediately. Expect reticulocyte crisis at day 5-7 and monitor K⁺ (drops with new hematopoiesis). No bone marrow biopsy needed if smear + B12 level confirm the diagnosis.
📋 Summary
Summary
Define the Problem
Anemia plus leukopenia plus thrombocytopenia together. The useful first split is failure of production versus peripheral destruction or sequestration, because that decides whether the answer is in the marrow or outside it.
The Smear Comes First
The peripheral smear is the cheapest and highest-yield test in the workup, and it frequently makes the diagnosis before the marrow is touched. Blasts mean leukemia. Hypersegmented neutrophils with a raised MCV mean B12 or folate deficiency. Schistocytes mean a microangiopathy. A leukoerythroblastic picture with teardrop cells means marrow infiltration or fibrosis. Dysplastic forms point to myelodysplastic syndrome.
Send the Reversible Causes Early
B12, folate, HIV, hepatitis serologies, TSH, LDH, haptoglobin, reticulocyte count, iron studies and copper.The reticulocyte count separates the two mechanisms: low means the marrow is not producing, high means the cells are being destroyed or lost in the periphery.
Review the Medication List Line by Line
Drugs are one of the commonest reversible causes. Methotrexate, chemotherapy, TMP-SMX, linezolid (especially beyond 2 weeks), valproate, carbamazepine, azathioprine, colchicine and alcohol. Stopping the drug is both the test and the treatment, and counts usually recover within days to weeks.
When the Marrow Biopsy Is Indicated
Unexplained pancytopenia after the initial labs, blasts on the smear, a leukoerythroblastic picture, or a clinical suspicion of leukemia or myelodysplasia.Aspirate and trephine together with cytogenetics and flow cytometry, because the cellularity itself is the answer: hypocellular suggests aplastic anemia, hypercellular suggests ineffective hematopoiesis as in myelodysplasia or megaloblastic anemia.
Do Not Forget the Spleen
Splenomegaly with pancytopenia is sequestration until proven otherwise, most often from cirrhosis with portal hypertension. The marrow here is normal, so a biopsy in an obviously cirrhotic patient with a large spleen adds risk without adding information.
Two Diagnoses Not to Miss
Acute leukemia, which is a treatment emergency, and hemophagocytic lymphohistiocytosis, where fever, splenomegaly, very high ferritin, high triglycerides and low fibrinogen accompany the cytopenias and untreated mortality is high. Also consider PNH when hemolysis and thrombosis accompany the cytopenias, since flow cytometry diagnoses it and a specific therapy exists.
Manage the Consequences While You Investigate
Neutropenic fever is a medical emergency: cultures and broad-spectrum antibiotics within 1 hour, before any imaging. Transfuse platelets below 10,000, or below 50,000 with bleeding or before a procedure. Use a restrictive red cell threshold. Use irradiated and leukoreduced products where a transplant is possible, and avoid transfusing a potential donor's relatives' blood, since sensitization compromises later engraftment.
Recognition and management of life-threatening chemo side effects: cardiotoxicity, mucositis, typhlitis, hemorrhagic cystitis, immune checkpoint toxicities, and infusion reactions.
🔍 Overview
Overview
Chemotherapy toxicities are a leading cause of treatment discontinuation, ICU admission, and death in cancer patients. The intern must recognize organ-specific toxicities by drug class: anthracyclines (cardiotoxicity), bleomycin (pulmonary fibrosis), cisplatin (nephro/oto/neurotoxicity), vinca alkaloids (neuropathy), cyclophosphamide (hemorrhagic cystitis), checkpoint inhibitors (immune-related adverse events in any organ). Key principle: know which chemo the patient received and its expected toxicity profile.
irAE Grading and Management
Grade
Severity
Action
Steroids
Grade 1
Mild symptoms
Continue checkpoint therapy, close monitoring
None (topical steroids for skin if needed)
Grade 2
Moderate, interferes with ADLs
Hold checkpoint therapy until resolves to Grade ≤ 1
Oral prednisone 0.5–1 mg/kg/day, taper over 4–6 weeks
Grade 3
Severe, hospitalization required
Hold checkpoint therapy, inpatient management
IV methylprednisolone 1–2 mg/kg/day, taper over ≥ 4 weeks
Grade 4
Life-threatening
Permanently discontinue checkpoint therapy
IV methylprednisolone 1–2 mg/kg + specialty consult (infliximab for colitis, MMF for hepatitis)
Common irAEs by Organ System
Organ
Presentation
Workup
Treatment
Skin
Maculopapular rash, pruritus, vitiligo
Clinical exam, biopsy if severe
Topical steroids, oral antihistamines; systemic steroids if Grade ≥ 3
GI (Colitis)
Diarrhea (watery, may be bloody), crampy abdominal pain
C. diff (rule out), CT abdomen, colonoscopy with biopsy
Acute emesis. Add dexamethasone + NK1 antagonist for high emetogenic regimens.
Palonosetron
0.25 mg IV
IV
Longer-acting 5-HT3 for delayed emesis prevention.
🏥 Rounds
Pimp Questions
❓ What is the most common immune-related adverse event from checkpoint inhibitors?
Thyroiditis/hypothyroidism (up to 10-20% with anti-PD-1). Often painless thyroiditis → transient hyperthyroidism → permanent hypothyroidism requiring levothyroxine. Check TSH q4-6 weeks. Unlike most irAEs, hypothyroidism does NOT require holding checkpoint therapy.
❓ Why should you avoid high FiO₂ in bleomycin lung toxicity?
Bleomycin causes pulmonary injury via free radical generation. High concentrations of oxygen provide more substrate for free radical production, worsening the lung injury. Target SpO₂ 88-92%. This is critical during surgery in patients with bleomycin history -anesthesia must avoid high FiO₂ even years later.
❓ What is MESNA and how does it work?
MESNA (2-mercaptoethane sulfonate sodium) binds acrolein, the toxic metabolite of cyclophosphamide and ifosfamide that causes hemorrhagic cystitis. MESNA is renally excreted and acts directly in the bladder lumen to neutralize acrolein. Always give with cyclophosphamide (especially high-dose) and ifosfamide.
❓ What is the cumulative dose limit for doxorubicin and why?
450-550 mg/m² lifetime. Above this threshold, risk of irreversible dilated cardiomyopathy increases sharply. Doxorubicin causes cardiotoxicity via free radical damage to cardiomyocytes + topoisomerase IIβ inhibition. Can occur during treatment (acute) or years later (late-onset). Monitor with serial echocardiography. Dexrazoxane is cardioprotective at high cumulative doses.
❓ How do you grade and manage checkpoint inhibitor hepatitis?
Typhlitis (neutropenic enterocolitis) = inflammation/necrosis of the cecum in severely neutropenic patients (ANC < 500), usually during chemo nadir. Presents with RLQ pain, fever, diarrhea (often bloody). CT: cecal wall thickening > 4mm, pericecal fat stranding, ± pneumatosis. Treatment: broad-spectrum antibiotics, NPO, IVF. Surgery only if perforation/peritonitis. Mortality 20-50%.
❓ When should you permanently discontinue checkpoint inhibitor therapy?
Grade 4 irAEs (life-threatening) require permanent discontinuation. Additionally, any grade of the following mandates permanent discontinuation: myocarditis (mortality up to 50%), encephalitis, myasthenia gravis, Guillain-Barré syndrome, and Grade 3+ pneumonitis that recurs after rechallenge. Grade 3 irAEs that do not improve to Grade ≤ 1 within 12 weeks of steroids should also lead to permanent discontinuation. Exception: endocrinopathies (thyroid, adrenal) managed with hormone replacement can allow continuation.
❓ Which irAE requires lifelong hormone replacement even after resolution?
Endocrine irAEs, particularly hypothyroidism (from checkpoint thyroiditis) and adrenal insufficiency (from hypophysitis destroying ACTH-producing cells). Unlike colitis, hepatitis, or pneumonitis, which can fully resolve with steroids, endocrine gland destruction is irreversible. Patients need lifelong levothyroxine (hypothyroidism) or hydrocortisone (adrenal insufficiency). New-onset type 1 diabetes from checkpoint therapy also requires lifelong insulin. These patients can often continue checkpoint therapy while on hormone replacement.
Clinical Examples
📋 Case 1, Checkpoint Inhibitor Colitis
Patient: 62M with metastatic melanoma on nivolumab (cycle 6). Presents with 4 days of watery diarrhea (8 episodes/day), diffuse crampy abdominal pain, low-grade fever. No blood in stool.
Diagnosis: Grade 3 immune-mediated colitis.
Key findings:
Grade 3, ≥ 7 stools/day over baseline, requires hospitalization
C. diff negative, must rule out infectious etiologies first
CT abdomen: diffuse pancolitis with wall thickening and fat stranding
Hold nivolumab, do not continue checkpoint therapy during Grade 3 irAE
Treatment: IV methylprednisolone 1–2 mg/kg/day. GI consult for colonoscopy with biopsy. If no improvement in 48–72 hours → infliximab 5 mg/kg. Slow steroid taper over ≥ 6 weeks once improved.
Sample Presentation
Mr. Davis is a 58-year-old man with metastatic melanoma on pembrolizumab (cycle 8) presenting with 5 days of watery diarrhea (8-10 episodes/day), crampy abdominal pain, no blood. Afebrile. Exam: diffuse abdominal tenderness, no peritoneal signs. Labs: WBC 11K, Cr 1.4 (baseline 0.9). C. diff negative. CT: diffuse colonic wall thickening. TSH 12 (baseline 2.5).
Key Points: Checkpoint inhibitor colitis (Grade 3 -≥ 7 stools/day over baseline) + new hypothyroidism. Hold pembrolizumab. Start methylprednisolone 1 mg/kg IV. If no improvement in 3 days → infliximab 5 mg/kg. Start levothyroxine for hypothyroidism. GI consult for possible colonoscopy with biopsy.
Hodgkin vs Non-Hodgkin Lymphoma Comparison
Feature
Hodgkin Lymphoma
Non-Hodgkin Lymphoma
Frequency
~10% of lymphomas
~90% of lymphomas
Age
Bimodal (20s and 60s)
Median age 60-70
Pathognomonic cell
Reed-Sternberg cell (CD15+/CD30+)
Varies by subtype (CD20+ B-cell most common)
Spread pattern
Contiguous (node to adjacent node)
Non-contiguous (can skip nodal groups)
Mediastinal mass
Very common (especially nodular sclerosis)
Less common (except primary mediastinal B-cell)
B symptoms
Common, affects staging
Present but less impact on staging
Extranodal disease
Rare at presentation
Common (GI, skin, CNS, bone marrow)
Prognosis
Excellent (> 80% cure)
Varies: indolent (incurable but long survival) to aggressive (curable with chemo)
Treatment
ABVD or BV-AVD ± radiation
Depends on subtype: R-CHOP (DLBCL), watch-and-wait (follicular), intensive chemo (Burkitt)
Ann Arbor Staging System
Stage
Definition
Clinical Relevance
I
Single lymph node region
Early stage, favorable prognosis. HL: ABVD × 2-4 + radiation. DLBCL: R-CHOP × 3 + radiation or R-CHOP × 6.
II
Two or more lymph node regions on the same side of the diaphragm
III
Lymph node regions on both sides of the diaphragm
Advanced stage. HL: ABVD × 6 or BV-AVD. DLBCL: R-CHOP × 6. Follicular: treat if symptomatic.
Staging Modifiers:A = no B symptoms. B = B symptoms present (fever > 38°C, drenching night sweats, weight loss > 10% in 6 months). E = extranodal extension from adjacent node. S = splenic involvement. X = bulky disease (> 10 cm or > 1/3 thoracic diameter). Example: Stage IIBS = both sides of diaphragm + B symptoms + spleen.
B Symptoms, Definition and Significance
B Symptoms (must know for rounds): (1) Fever > 38°C (unexplained, not from infection). (2) Drenching night sweats (requiring change of clothes/sheets). (3) Weight loss > 10% body weight in 6 months. B symptoms indicate higher tumor burden and worse prognosis. In HL, B symptoms upstage the disease (Stage IIB is treated as advanced stage). Note: pruritus and alcohol-induced lymph node pain (Hodgkin-specific) are NOT B symptoms but are associated findings.
📋 Case 2, Checkpoint Inhibitor Thyroiditis
Patient: 54F with NSCLC on pembrolizumab (cycle 4). Routine labs show TSH 45 mIU/L (baseline 2.1), free T4 0.3 ng/dL (low). Patient reports fatigue, weight gain, constipation.
TSH markedly elevated with low free T4, overt hypothyroidism
Painless thyroiditis, may have had transient hyperthyroid phase (often missed)
Most common endocrine irAE, occurs in 10–20% of anti-PD-1 patients
Does NOT require holding checkpoint therapy, unlike most other irAEs
Treatment: Start levothyroxine 1.6 mcg/kg/day. Continue pembrolizumab. Monitor TSH q6–8 weeks and titrate. This is typically permanent, lifelong levothyroxine replacement needed.
📋 Case 3, Checkpoint Inhibitor Hepatitis
Patient: 48M with advanced RCC on ipilimumab/nivolumab (cycle 3). Labs: AST 580 (14x ULN), ALT 640 (16x ULN), T. bili 2.1, ALP 180. Asymptomatic.
Diagnosis: Grade 3 immune-mediated hepatitis.
Key findings:
AST/ALT > 10x ULN, Grade 3 hepatitis (5–20x ULN)
Hepatitis panel negative, rule out viral hepatitis (HBV reactivation with immunotherapy)
Ipilimumab/nivolumab combo, highest rate of irAEs (~60%), hepatitis in ~15%
Often asymptomatic, caught on routine monitoring LFTs
Treatment: Hold ipilimumab/nivolumab. IV methylprednisolone 1–2 mg/kg/day. If refractory → add mycophenolate (NOT infliximab, it is hepatotoxic). Monitor LFTs daily until downtrending. Taper steroids over ≥ 4 weeks.
Monitoring
CBC nadir -typically day 7-14 (day 21-28 for nitrosoureas). Check CBC before each cycle.
Echo/MUGA q3 months on anthracyclines -stop if EF drops > 10% below baseline to < 50%
PFTs before and during bleomycin -stop if DLCO drops > 20%
Cr + Mg with cisplatin (nephrotoxicity + magnesium wasting)
Audiometry with cisplatin (ototoxicity -irreversible high-frequency hearing loss)
TSH q4-6 weeks on checkpoint inhibitors (thyroiditis → hypothyroidism)
LFTs q2-4 weeks on checkpoint inhibitors (hepatitis)
Urine output + UA with cyclophosphamide (hemorrhagic cystitis)
📋 Summary
Summary
Know the Drug, Know the Organ
Bleomycin = lungs (pulmonary fibrosis, and avoid high FiO₂). Doxorubicin = heart (dilated cardiomyopathy, with a lifetime cumulative dose limit). Cisplatin = kidneys and ears (nephrotoxicity, ototoxicity, magnesium wasting). Cyclophosphamide = bladder (hemorrhagic cystitis). Vincristine = nerves (peripheral neuropathy, and fatal if given intrathecally). 5-FU and methotrexate = mucositis.
Hemorrhagic Cystitis Is Preventable
Acrolein, a cyclophosphamide and ifosfamide metabolite, injures the bladder urothelium.Prevent with aggressive hydration plus mesna, which binds acrolein in the urine. Treat established disease with continuous bladder irrigation, and remember ifosfamide also causes an encephalopathy treated with methylene blue.
Neutropenic Enterocolitis Is Easy to Miss
Typhlitis: right lower quadrant pain and fever in a neutropenic patient, with cecal wall thickening on CT.It mimics appendicitis but is managed medically with bowel rest, broad-spectrum antibiotics covering anaerobes, and G-CSF, with surgery reserved for perforation or uncontrolled bleeding. Operating on uncomplicated typhlitis makes it worse.
Immune-Related Adverse Events Are a Different Species
Checkpoint inhibitors cause autoimmunity, not cytotoxicity, so the mechanism, the timing and the treatment all differ from classical chemotherapy toxicity. They can appear weeks to months after the last dose, including after the drug has been stopped, which is why a patient off treatment is not off risk.
Grade Drives the Response
Grade 1: continue with monitoring. Grade 2: hold the drug, start prednisone about 0.5 to 1 mg/kg. Grade 3 to 4: stop the drug, give methylprednisolone 1 to 2 mg/kg, and add a second agent (infliximab, mycophenolate) if there is no improvement in 48 to 72 h.Taper steroids over at least 4 to 6 weeks, because a fast taper relapses.
Know Which irAEs Kill
Colitis is the commonest severe one and can perforate; use infliximab for steroid-refractory colitis, but not if perforation is suspected. Pneumonitis presents as breathlessness with ground-glass change and is easily mistaken for infection or progression. Myocarditis is rare but has very high mortality and needs high-dose steroids immediately. Hypophysitis and adrenal insufficiency present as fatigue and hypotension and are fatal if the cortisol is not replaced.
The One irAE You Do Not Stop Treatment For
Endocrine irAEs (thyroiditis, hypophysitis, type 1 diabetes) are usually permanent and are managed with hormone replacement rather than immunosuppression, and the checkpoint inhibitor is often continued. Steroids do not reverse them, so giving high-dose steroids for an isolated hypothyroidism adds harm without benefit.
Infusion Reactions and the Long-Term Watch
Distinguish a rate-related infusion reaction, which responds to slowing and premedication, from true anaphylaxis, which does not.Rituximab and taxanes are the classic offenders.Long term, track cumulative anthracycline dose with serial echocardiograms, PFTs with DLCO on bleomycin, audiometry on cisplatin, and remember that secondary malignancy after alkylators and topoisomerase inhibitors appears years later in patients who consider themselves cured.
Hodgkin and Non-Hodgkin lymphoma recognition, staging workup, and inpatient complication management for medical residents.
🔍 Overview
Overview
Lymphoma = malignancy of lymphocytes. Two major categories: Hodgkin lymphoma (HL) -bimodal peak (20s and 60s), Reed-Sternberg cells, excellent prognosis (cure rate > 80%), contiguous nodal spread. Non-Hodgkin lymphoma (NHL) -much more common (90% of lymphomas), heterogeneous group from indolent (follicular) to aggressive (DLBCL, Burkitt). Key teaching point for interns: you are not expected to manage the chemo -you are expected to recognize lymphoma, complete the staging workup, manage inpatient complications (tumor lysis, febrile neutropenia, cord compression, SVC syndrome), and ensure tissue gets to pathology properly.
🧪 Workup
Workup
Excisional lymph node biopsy -gold standard. NOT fine needle aspiration (FNA). FNA disrupts architecture needed for subtyping. Core needle biopsy acceptable if excisional not feasible.
PET-adapted: interim PET after 2 cycles guides therapy intensity.
DLBCL (most common aggressive NHL):R-CHOP × 6 cycles (rituximab + cyclophosphamide/doxorubicin/vincristine/prednisone). Cure rate 60-70%. CNS prophylaxis with intrathecal methotrexate for high-risk (testicular, breast, kidney, adrenal involvement). GELA, 2002
Follicular lymphoma (indolent): Watch-and-wait for asymptomatic low tumor burden. Treat when symptomatic: rituximab ± bendamustine or CHOP. Not curable with standard therapy -median survival > 15 years with serial treatments.
Burkitt lymphoma: Medical emergency -fastest growing human tumor. Hyper-CVAD or similar intensive regimen. TLS prophylaxis critical (aggressive IVF + rasburicase).
96-hour continuous infusion, requires central access. More toxic than R-CHOP but better outcomes for high-risk NHL. Dunleavy, 2013
BR
Bendamustine + Rituximab
Indolent NHL (follicular, marginal zone)
Well-tolerated. Less alopecia and neuropathy than R-CHOP. BRIGHT, 2014
Mnemonic, ABVD side effects:A driamycin = cardiotoxicity (echo before each cycle) · B leomycin = pulmonary fibrosis (PFTs) · V inblastine = myelosuppression · D acarbazine = severe nausea (give strong antiemetics)
💊 Medications
Medications
Drug
Dose/Regimen
Route
Notes
R-CHOP
Rituximab + Cyclo/Doxo/Vincristine/Pred
IV
Standard for DLBCL. q21 days × 6 cycles. GELA, 2002
ABVD
Doxorubicin/Bleomycin/Vinblastine/Dacarbazine
IV
Standard for Hodgkin. q28 days. Monitor PFTs (bleomycin).
Rituximab
375 mg/m²
IV
Anti-CD20. Infusion reactions common (premedicate). Screen HBV (reactivation risk -give entecavir prophylaxis if HBsAg+ or anti-HBc+).
Brentuximab vedotin
1.2 mg/kg q2wk
IV
Anti-CD30 ADC. HL + some NHL. Peripheral neuropathy. ECHELON-1, 2018
TMP-SMX
1 DS tab Mon/Wed/Fri
PO
PCP prophylaxis during and 6 months after R-CHOP/ABVD.
Acyclovir
400 mg BID
PO
VZV prophylaxis during chemo.
Entecavir
0.5 mg daily
PO
HBV prophylaxis if anti-HBc positive + receiving rituximab.
🏥 Rounds
Pimp Questions
❓ Why should you NOT do FNA for suspected lymphoma?
FNA provides individual cells but destroys the lymph node architecture needed for subtyping. Lymphoma diagnosis requires: architecture assessment (follicular vs diffuse), immunohistochemistry panel (CD20, CD3, CD15, CD30, Ki-67), and often FISH/cytogenetics. An excisional biopsy (or at minimum core needle biopsy) provides all of this. FNA can suggest lymphoma but cannot subtype it.
❓ What are B symptoms and why do they matter?
B symptoms: (1) Fever > 38°C, (2) drenching night sweats, (3) weight loss > 10% in 6 months. They indicate higher disease burden and worse prognosis. In Hodgkin lymphoma, B symptoms upstage the disease (Stage IIB is treated like advanced stage). Pruritus and alcohol-induced pain are associated symptoms but not technically B symptoms.
❓ Why must you screen for hepatitis B before starting rituximab?
Rituximab (anti-CD20) depletes B cells → HBV reactivation risk. Even patients with resolved infection (HBsAg−, anti-HBc+) can reactivate. Reactivation can cause fulminant hepatic failure. Screen ALL patients with HBsAg, anti-HBs, anti-HBc. If anti-HBc positive → start entecavir prophylaxis and monitor HBV DNA monthly. Continue prophylaxis 12 months after last rituximab dose.
❓ What is the difference between Hodgkin and Non-Hodgkin lymphoma?
Hodgkin: Reed-Sternberg cells (CD15+/CD30+), bimodal age (20s, 60s), contiguous spread (node to adjacent node), excellent prognosis (> 80% cure), mediastinal mass common. NHL: much more common (90%), diverse subtypes, non-contiguous spread, prognosis varies (follicular = indolent/incurable vs DLBCL = aggressive/curable vs Burkitt = ultra-aggressive).
❓ When do you "watch and wait" vs treat lymphoma?
Watch and wait is appropriate for asymptomatic follicular lymphoma with low tumor burden. Criteria for treatment: B symptoms, cytopenias from marrow involvement, bulky disease (> 7 cm), organ compression, rapid growth, or patient preference. Treating asymptomatic follicular lymphoma does not improve survival. For ALL aggressive lymphomas (DLBCL, Burkitt, HL with B symptoms), treatment should start promptly.
❓ What fertility counseling is needed before starting lymphoma chemotherapy?
Alkylating agents (cyclophosphamide, procarbazine) and radiation cause gonadal toxicity. Men: sperm banking before first cycle. Women: oocyte/embryo cryopreservation (requires 2 weeks for ovarian stimulation -discuss urgency with oncology). ABVD has lower gonadal toxicity than BEACOPP. Document the fertility discussion -it is a quality measure and medicolegal requirement.
❓ What is tumor lysis syndrome (TLS) and how do you prevent it in lymphoma patients?
TLS occurs when rapid tumor cell death releases intracellular contents: hyperuricemia, hyperkalemia, hyperphosphatemia, hypocalcemia. Can cause acute kidney injury, cardiac arrhythmias, seizures, and death. Highest risk: Burkitt lymphoma (fastest-growing human tumor), DLBCL with high tumor burden, high LDH, bulky disease. Prevention: (1) Aggressive IV hydration (200-250 mL/hr). (2) Allopurinol (prevents new uric acid formation) for intermediate risk. (3) Rasburicase (breaks down existing uric acid) for high risk,do NOT give to G6PD-deficient patients (hemolysis). (4) Monitor K, phos, Ca, uric acid, creatinine q6-8h for 48-72h after starting chemo. Avoid alkalinizing urine (promotes calcium phosphate precipitation).
❓ What is the Deauville score and how is it used in lymphoma management?
The Deauville score (1-5) is used to interpret interim and end-of-treatment PET/CT in lymphoma. It compares FDG uptake in residual lesions to reference structures: 1 = no uptake. 2 = uptake ≤ mediastinum. 3 = uptake > mediastinum but ≤ liver. 4 = uptake moderately > liver. 5 = markedly > liver or new lesions. Deauville 1-3 = complete metabolic response (good). Deauville 4-5 = residual disease (may need treatment change). In Hodgkin lymphoma, interim PET (after 2 cycles) guides therapy: Deauville 1-3 may allow de-escalation (drop bleomycin); Deauville 4-5 may require escalation to BEACOPP or BV-AVD. RATHL, 2016
Clinical Examples
📋 Case 1, Classic Hodgkin Lymphoma with Mediastinal Mass
Patient: 24F presents with 2 months of dry cough, dyspnea on exertion, and a 15 lb weight loss. She also reports drenching night sweats requiring changing her sheets nightly. No fevers.
Exam: Non-tender left supraclavicular lymphadenopathy (2.5 cm, rubbery). No hepatosplenomegaly.
Imaging: CXR: large anterior mediastinal mass. CT chest: 12 cm mediastinal mass with bilateral hilar lymphadenopathy. PET/CT: intensely FDG-avid mediastinal, bilateral hilar, and left supraclavicular nodes. No disease below diaphragm.
Biopsy: Excisional biopsy of supraclavicular node: Reed-Sternberg cells in background of mixed inflammatory infiltrate. IHC: CD15+, CD30+, CD20−. Consistent with nodular sclerosis classical Hodgkin lymphoma.
Staging: Stage IIB (bilateral hilar = still same side of diaphragm, B symptoms present). Despite being stage II, B symptoms → treated as advanced stage.
Teaching Point: Nodular sclerosis is the most common HL subtype, classically presenting in young women with a mediastinal mass. B symptoms upstage IIA to advanced-stage treatment protocols. PET-adapted therapy allows de-escalation to reduce bleomycin toxicity.
📋 Case 2, Diffuse Large B-Cell Lymphoma (DLBCL)
Patient: 67M presents with 3 weeks of rapidly enlarging right neck mass, fatigue, and unintentional 12 lb weight loss. No night sweats or fevers.
Exam: 5 cm firm, non-tender right cervical mass. Left axillary lymphadenopathy (3 cm). Spleen palpable 2 cm below costal margin.
Imaging: PET/CT: FDG-avid bilateral cervical, axillary, retroperitoneal nodes + splenic involvement. No bone marrow uptake on PET.
Biopsy: Core needle biopsy: diffuse proliferation of large CD20+ B cells, Ki-67 > 80%. BCL2+ by IHC. FISH: no MYC rearrangement (rules out double-hit). Diagnosis: DLBCL, GCB subtype.
Staging: Stage IIIA (nodes both sides of diaphragm + spleen, no B symptoms).
Teaching Point: DLBCL is the most common aggressive NHL. R-CHOP is curative in 60-70%. Always check anti-HBc before rituximab, even resolved HBV can reactivate fatally. LDH correlates with tumor burden and is prognostic (part of IPI score).
📋 Case 3, Follicular Lymphoma
Patient: 55F found to have bilateral inguinal lymphadenopathy on routine physical exam. Completely asymptomatic. No B symptoms, no fatigue, no cytopenias.
Exam: Bilateral inguinal nodes (2-3 cm), rubbery, non-tender. No other palpable lymphadenopathy. No hepatosplenomegaly.
Staging: Stage IIIA (nodes both sides of diaphragm, no symptoms).
Management:
Low tumor burden (GELF criteria not met: no node > 7 cm, no B symptoms, no cytopenias, no organ compression).
Watch and wait, no treatment initiated. Active surveillance with exam + labs q3 months, CT q6 months.
Patient counseled: follicular lymphoma is not curable with standard therapy, but median survival is > 15-20 years with serial treatments. Early treatment does NOT improve overall survival.
Criteria to initiate treatment: development of B symptoms, cytopenias, bulky disease (> 7 cm), rapid growth, organ compression, or patient preference.
When treatment needed: options include rituximab monotherapy, BR (bendamustine-rituximab), or R-CHOP.
Teaching Point: Follicular lymphoma is the classic "watch and wait" lymphoma. Asymptomatic patients with low tumor burden should NOT be treated. This is one of the hardest conversations in oncology, telling a patient they have cancer but you are not going to treat it. Treatment does not improve OS in asymptomatic disease, and each line of therapy has toxicity.
Monitoring
CBC before each cycle -delay if ANC < 1000 or platelets < 100K
Echo q3 months during anthracycline therapy (doxorubicin cardiotoxicity)
PFTs during bleomycin therapy -stop if DLCO drops > 20% from baseline
HBV DNA monthly if on rituximab with HBV risk (reactivation can be fatal)
LDH + uric acid before each cycle -rising LDH suggests progression; high uric acid = TLS risk
Post-treatment surveillance: CT q6 months × 2 years, then annually × 5 years. PET only if suspected relapse (not for routine surveillance).
Sample Presentation
Mr. Rodriguez is a 28-year-old man presenting with 6 weeks of painless left cervical lymphadenopathy (3 cm), night sweats, 10 lb weight loss, and pruritus. No fevers. No cough. Exam: firm, rubbery, non-tender left cervical and left supraclavicular nodes. No hepatosplenomegaly. Labs: WBC 9K, Hgb 11.8, LDH 320 (elevated), ESR 45. CXR: mediastinal widening.
Key Points: Young male with B symptoms (weight loss > 10%, night sweats) + painless lymphadenopathy + mediastinal mass = classic Hodgkin lymphoma until proven otherwise. Next step: excisional lymph node biopsy (NOT FNA). Expect Reed-Sternberg cells (CD15+/CD30+). Staging with PET/CT. ABVD × 2-6 cycles based on stage. Cure rate > 80%.
📋 Summary
Summary
Hodgkin or Non-Hodgkin
Hodgkin: bimodal age distribution, contiguous nodal spread, Reed-Sternberg cells, B symptoms common, and highly curable.Non-Hodgkin: older, non-contiguous spread, far more heterogeneous, and frequently extranodal.DLBCL is the commonest aggressive NHL and is curable; follicular is indolent and generally is not.
Get an Excisional Biopsy
A fine needle aspirate is not sufficient to diagnose lymphoma. The diagnosis depends on architecture, not just cells, so an excisional or core biopsy with immunohistochemistry and flow cytometry is required. Sending a patient for an FNA usually just costs two weeks and a second procedure.
Stage With PET-CT and Ask About B Symptoms
Lugano staging with PET-CT, plus bone marrow biopsy where indicated. B symptoms are fever above 38°C, drenching night sweats and unintentional weight loss above 10% in 6 months, and they upstage the disease. Baseline echocardiogram before anthracyclines and PFTs before bleomycin, since those toxicities are what limit therapy.
Know the Two Regimens You Will See
ABVD for Hodgkin lymphoma: Adriamycin (cardiotoxic, echo monitoring), Bleomycin (pulmonary fibrosis, monitor PFTs and stop if DLCO falls more than 25%), Vinblastine (myelosuppression), Dacarbazine (severe nausea). R-CHOP for DLBCL, six 21-day cycles; adding rituximab produced roughly a 15% survival benefit and changed the disease from often fatal to usually curable.
Watch the Specific Toxicities
Anthracycline cardiotoxicity is cumulative and dose-limiting, so track the lifetime dose and the ejection fraction. Bleomycin pneumonitis can be fatal and is worsened by high FiO₂, which matters if the patient ever needs anesthesia. Vincristine is fatal if given intrathecally and causes peripheral neuropathy and constipation. Rituximab reactivates hepatitis B, so screen HBsAg and core antibody before the first dose.
Prevent Tumor Lysis in the Bulky and the Aggressive
Burkitt, double-hit lymphoma and any bulky, rapidly proliferating disease are high risk.Fluids plus allopurinol, or rasburicase for high risk, with labs every 6 to 8 h during the first cycle. Rasburicase is contraindicated in G6PD deficiency.
Recognize the Oncologic Emergencies
Superior vena cava syndrome from a mediastinal mass, with facial swelling, distended neck veins and orthopnea. Spinal cord compression, where back pain precedes weakness and dexamethasone plus an urgent MRI comes before anything else. Airway compromise from a large mediastinal mass, which makes sedation and supine positioning genuinely dangerous. CNS involvement, needing intrathecal prophylaxis in high-risk disease.
Plan the Survivorship at the Start
Discuss fertility preservation before the first cycle, not after.Long-term risks are real in a cured population: secondary malignancies, particularly breast cancer after mediastinal radiation in young women, myelodysplasia and AML after alkylators, cardiovascular disease, and hypothyroidism after neck radiation. Add PJP prophylaxis and antiviral prophylaxis where the regimen warrants, and vaccinate before therapy where possible.
Life-threatening diabetic emergency with extreme hyperglycemia (> 600), hyperosmolality (> 320), and profound dehydration. Mortality 5-20% -much higher than DKA.
🔍 Overview
Overview
HHS is a diabetic emergency characterized by severe hyperglycemia (> 600 mg/dL), hyperosmolality (> 320 mOsm/kg), and profound dehydration (average 8-10L deficit) without significant ketoacidosis (pH > 7.30, bicarb > 18, minimal ketonemia). [ADA Consensus, Kitabchi 2009 Occurs almost exclusively in Type 2 diabetes, typically in elderly patients with limited water access (nursing home, dementia, post-CVA). Mortality is 5-20% -much higher than DKA -because patients are older with more comorbidities and the degree of dehydration is more severe. Triggers: infection (#1, especially UTI/pneumonia), medication non-compliance, new diabetes diagnosis, MI, stroke, medications (steroids, thiazides). Key difference from DKA: HHS patients have enough insulin to prevent lipolysis/ketogenesis, but not enough for glucose uptake. Treatment priority: fluids first, insulin second.
BMP -Na⁺ (correct for hyperglycemia: add 1.6 mEq per 100 mg/dL glucose above 100), K⁺ (total body depleted even if serum normal/elevated), Cr (pre-renal AKI from dehydration), bicarb (should be > 18 in pure HHS)
ECG -rule out MI as trigger. Check for hyperkalemia/hypokalemia changes.
Lipase -pancreatitis can trigger HHS
🚨 Management
Management
Step 1 -AGGRESSIVE IV FLUIDS (priority #1):
NS 1-1.5 L/hr × first 1-2 hours (15-20 mL/kg/hr). These patients are 8-10L depleted.
After initial bolus: NS 250-500 mL/hr if corrected Na low or normal. 0.45% NS if corrected Na elevated.
When glucose < 300 → add D5 0.45% NS (not D5W -need to continue volume repletion).
Step 2 -POTASSIUM REPLETION: Check K⁺ before insulin. If K⁺ < 3.5 → replete BEFORE insulin (10-20 mmol/hr until > 3.5). If 3.5-5.0 → add 20-40 mEq K⁺ per liter of IVF. If > 5.3 → hold K⁺, recheck in 2h.
Step 3 -INSULIN (lower priority than fluids): Regular insulin 0.1 U/kg/hr IV drip (no bolus in HHS). Start AFTER 1-2L fluids and confirmed K⁺ > 3.5. Target glucose decline: 50-70 mg/dL per hour. Reduce rate to 0.02-0.05 U/kg/hr when glucose < 300. ADA Hyperglycemic Crises Protocol, Kitabchi 2009
Step 4 -TREAT THE TRIGGER: Antibiotics for infection. Hold offending medications. Manage MI/stroke if present.
Step 5 -DVT PROPHYLAXIS: Enoxaparin 40 mg SQ daily. HHS is a hypercoagulable state (hemoconcentration + immobility).
⚠ Do NOT drop osmolality > 3 mOsm/kg/hr -risk of cerebral edema (especially in elderly). Fluids alone will drop glucose significantly before insulin is even started. Fluids first, insulin second.
💊 Medications
Medications
Drug
Dose
Route
Notes
NS (0.9% NaCl)
1-1.5 L/hr × 1-2h → 250-500 mL/hr
IV
First-line. Priority #1. Average deficit 8-10L. Switch to 0.45% if corrected Na high.
Regular insulin
0.1 U/kg/hr (no bolus)
IV drip
Start AFTER fluids + K⁺ > 3.5. Target BG drop 50-70/hr. Reduce when < 300.
KCl
20-40 mEq per liter IVF
IV
Total body K⁺ depleted. Replete before insulin. K⁺ < 3.5 → hold insulin until repleted.
D5 + 0.45% NS
150-250 mL/hr
IV
When glucose < 300. Continue volume repletion while preventing hypoglycemia.
Enoxaparin
40 mg SQ daily
SQ
DVT prophylaxis -HHS is hypercoagulable.
Glargine
0.2-0.3 U/kg SQ
SQ
Give 2-4h BEFORE stopping insulin drip for transition. Do NOT stop drip without basal overlap.
🏥 Rounds
Pimp Questions
❓ What is the key pathophysiologic difference between HHS and DKA?
In HHS, patients have enough circulating insulin to prevent lipolysis and ketogenesis, but not enough for peripheral glucose uptake. So they develop extreme hyperglycemia without significant ketoacidosis. In DKA, there is absolute insulin deficiency → uninhibited lipolysis → ketone body production → metabolic acidosis. This is why HHS is nearly exclusive to Type 2 DM (some residual insulin production).
❓ Why are fluids more important than insulin in HHS?
HHS patients have an average 8-10L fluid deficit (vs 3-5L in DKA). Aggressive IV fluids alone will drop glucose by 75-100 mg/dL per hour through dilution + improved renal perfusion → glycosuria. Starting insulin before adequate hydration risks cardiovascular collapse (glucose drops → water moves intracellularly → further intravascular depletion) and cerebral edema (too-rapid osmolality correction).
❓ How do you calculate corrected sodium in hyperglycemia?
Corrected Na = measured Na + 1.6 × [(glucose − 100) / 100]. Hyperglycemia causes osmotic water shift from ICF to ECF → dilutional hyponatremia. The corrected Na tells you the true sodium status. If corrected Na is elevated → the patient is even more hyperosmolar and dehydrated than the measured Na suggests. Use corrected Na to guide IVF choice (0.9% vs 0.45% NS).
❓ Why is mortality in HHS so much higher than DKA?
HHS mortality is 5-20% (vs 1-5% for DKA) because: (1) patients are older with more comorbidities, (2) the trigger is often a serious acute illness (MI, stroke, sepsis), (3) degree of dehydration is much more severe (8-10L), (4) hyperosmolality itself causes end-organ damage, (5) HHS is a hypercoagulable state → arterial and venous thrombosis.
❓ What is the risk of correcting osmolality too quickly?
Cerebral edema. The brain adapts to chronic hyperosmolality by generating idiogenic osmoles (intracellular solutes). Rapid correction of serum osmolality causes water to shift into brain cells → edema. Target osmolality decline ≤ 3 mOsm/kg/hr. This is analogous to osmotic demyelination in too-rapid sodium correction.
❓ When do you transition from IV insulin drip to subcutaneous insulin?
When the patient meets ALL of: (1) glucose < 300, (2) osmolality < 315, (3) alert and eating. Give basal insulin (glargine 0.2-0.3 U/kg) 2-4 hours BEFORE stopping the drip -the drip has a half-life of only 5-10 minutes, so any gap in coverage → rebound hyperglycemia.
Clinical Examples
📋 Case 1, Nursing Home HHS with UTI Trigger
Patient: 82F, T2DM on metformin + glipizide, dementia, HTN. Brought from SNF with 4 days of progressive lethargy, decreased PO intake, and new urinary incontinence.
Key findings: T 100.8°F, HR 108, BP 88/52. Glucose 1,040, Na 152 (corrected 167), K 4.6, Cr 3.2 (baseline 1.0), serum osm 398, pH 7.32, bicarb 22, BHB 0.6. UA: pyuria + bacteria.
Management:
NS 1.5 L/hr x 2 hours, then 500 mL/hr; switch to 0.45% NS when corrected Na begins to normalize
Insulin 0.1 U/kg/hr IV (NO bolus) started after first liter of fluids and K confirmed > 3.5
Ceftriaxone 1g IV for UTI (trigger treatment)
DVT prophylaxis with enoxaparin (HHS is a hypercoagulable state)
Target glucose drop 50-70 mg/dL/hr; target osm correction ≤ 3 mOsm/kg/hr
Teaching point: Fluids alone drop glucose 75-100 mg/dL/hr. The corrected sodium reveals the true degree of dehydration. Always identify and treat the trigger.
📋 Case 2, HHS/DKA Overlap Syndrome
Patient: 55M, T2DM on insulin (non-adherent x 2 weeks), obesity, CKD stage 3. Presents with confusion, vomiting, and polyuria.
Key findings: HR 118, BP 96/60. Glucose 890, Na 131 (corrected 144), K 5.8, Cr 4.1 (baseline 1.8), pH 7.18, bicarb 10, AG 28, BHB 5.2, serum osm 342.
Management:
HHS/DKA overlap, meets criteria for both (glucose > 600, osm > 320, AND AG acidosis + elevated ketones)
Aggressive NS resuscitation 1 L/hr; K 5.8 so safe to start insulin immediately
Insulin drip 0.1 U/kg/hr (treat ketoacidosis like DKA; follow BHB to resolution)
When glucose reaches 300: switch to D5 0.45% NS + reduce insulin to 0.02-0.05 U/kg/hr
Monitor K q2h, will drop rapidly with insulin and fluids
Teaching point: Up to 30% of hyperglycemic emergencies have overlap features. Treat the ketoacidosis like DKA (close the anion gap) while managing hyperosmolarity like HHS (gradual osm correction). The K of 5.8 is falsely reassuring, total body K is depleted. ADA Consensus, Kitabchi 2009
📋 Case 3, HHS Complicated by Cerebral Edema
Patient: 70F, T2DM on sulfonylurea, found confused at home for 2+ days. Started on aggressive IV fluids and insulin at outside hospital before transfer.
Key findings: Glucose dropped from 1,100 to 450 in 4 hours. Osm corrected from 410 to 340 (17.5 mOsm/hr). Patient now obtunded with new fixed dilated left pupil.
Management:
Stat CT head, cerebral edema confirmed
Mannitol 1 g/kg IV bolus or hypertonic saline 3% 250 mL
Elevate head of bed to 30 degrees
STOP hypotonic fluids; switch to NS to prevent further osmolality drop
Neurosurgery consult for possible EVD placement
Teaching point: Cerebral edema from overly aggressive correction is the most feared HHS complication. The brain generates idiogenic osmoles to adapt to chronic hyperosmolality. Target osm decline ≤ 3 mOsm/kg/hr and glucose decline 50-70 mg/dL/hr. This patient's osm dropped at nearly 6x the safe rate.
Sample Presentation
Mrs. Williams is an 78-year-old woman with T2DM, dementia, and HTN, brought from nursing home with 3 days of altered mental status, decreased PO intake, and new incontinence. VS: T 100.4°F, HR 112, BP 92/58, RR 20. Exam: dry mucous membranes, tenting, somnolent but arousable. Labs: glucose 923, Na 149 (corrected 163), K 4.8, Cr 2.8 (baseline 1.1), pH 7.34, bicarb 20, BHB 0.8, serum osm 384. UA: pyuria. CXR: clear.
Key Points: Classic HHS -glucose > 600, osm > 320, no significant ketoacidosis. Trigger: UTI (pyuria + fever). Start NS 1.5L/hr. K⁺ is adequate → can start insulin at 0.1 U/kg/hr after first 1-2L fluids. Treat UTI empirically. DVT prophylaxis. ICU for monitoring. This patient has ~10L fluid deficit.
BMP q2-4h -K⁺ (shifts dramatically with insulin), Na⁺ (corrected Na should rise as glucose falls -if not, you're giving too much free water), Cr (improving = adequate hydration)
Glucose above 600 mg/dL, effective osmolality above 320 mOsm/kg, and profound dehydration, with little or no ketoacidosis. Typically an older type 2 diabetic over days to weeks. Mortality is 5 to 20%, considerably higher than DKA, largely because of age, comorbidity and the precipitating illness rather than the glucose itself.
Why There Are No Ketones
Residual insulin is enough to suppress lipolysis but not enough to control glucose. That is the whole difference from DKA, and it explains the slower onset: without ketoacidosis there is no early symptom to drive the patient in, so they present days later, far more dehydrated and more obtunded.
Fluids First, Insulin Second
The average deficit is 8 to 10 liters. Give normal saline 1 to 1.5 L/h for the first 1 to 2 h, then 250 to 500 mL/h, switching to 0.45% if the corrected sodium is high. Fluid alone drops the glucose substantially before any insulin is given, by restoring renal perfusion and glycosuria. Starting insulin first collapses the intravascular volume by pulling water into cells.
Check Potassium Before the Insulin
Total body potassium is depleted even when the serum level looks normal or high.Hold insulin until potassium is above 3.5 and add 20 to 40 mEq per liter of fluid, because insulin drives potassium into cells and can precipitate a fatal arrhythmia in a patient who is already depleted.
Correct Slowly
Do not drop the osmolality faster than about 3 mOsm/kg/h, and aim for a glucose fall of 50 to 70 mg/dL/h.The brain has adapted to a hyperosmolar state, so rapid correction causes cerebral edema, and the elderly are at highest risk. Slow is safe here in a way it is not in most resuscitations.
Insulin Infusion Without a Bolus
Regular insulin 0.1 units/kg/h, no loading dose.Add D5 to the fluids once the glucose falls below about 300 and continue the infusion, because the goal is to clear the hyperosmolar state, not simply to normalize the glucose. Stopping insulin at a normal glucose leaves the osmolality uncorrected.
Hunt the Precipitant
Infection is the commonest trigger, then myocardial infarction, stroke, medication non-adherence, and drugs including steroids, thiazides and atypical antipsychotics. The precipitant, not the glucose, is usually what determines whether the patient survives, so the workup runs in parallel with the resuscitation.
Two Things That Get Forgotten
HHS is prothrombotic, so give DVT prophylaxis (enoxaparin 40 mg SC daily) unless contraindicated: the combination of hyperviscosity, dehydration and immobility makes thrombosis common. Overlap the transition off the drip: give subcutaneous basal insulin 2 to 4 h before stopping the infusion, because IV insulin has a half-life of minutes and stopping it cleanly sends the glucose straight back up.
Life-threatening decompensated hypothyroidism. Mortality 25-60%. Classic: hypothermia + AMS + precipitating event in a patient with untreated hypothyroidism.
🔍 Overview
Overview
Myxedema coma is the most severe form of hypothyroidism, representing decompensation of long-standing untreated or undertreated disease. Despite the name, actual coma is present in only ~20% -most present with AMS, obtundation, or extreme lethargy. Mortality is 25-60% even with treatment. Classic triad: (1) altered mental status, (2) hypothermia (often < 95°F/35°C), (3) precipitating event. Triggers: infection (#1), cold exposure, sedatives/opioids, surgery, MI, stroke, medication non-compliance. Almost exclusively affects elderly women in winter. Think of it as multi-organ failure from severe thyroid hormone deficiency: decreased cardiac output, hypoventilation (CO₂ retention), hypothermia, hyponatremia (impaired free water excretion), hypoglycemia, and ileus.
🧪 Workup
Workup
TSH -markedly elevated in primary hypothyroidism (most cases). Low/normal TSH = central (pituitary) hypothyroidism.
Free T4 -very low. Free T3 also low but less reliable.
AM cortisol -MUST check before giving levothyroxine. Concomitant adrenal insufficiency is common (either autoimmune polyendocrine syndrome or central hypothyroidism with secondary AI). Giving T4 without cortisol replacement → adrenal crisis.
ABG/VBG -respiratory acidosis (CO₂ retention from hypoventilation). May need intubation.
CBC -anemia (chronic disease), possible leukocytosis if infection triggered
CK -rhabdomyolysis from hypothyroid myopathy
🚨 Management
Management
Step 1 -Stress-dose steroids FIRST:Hydrocortisone 100 mg IV before or simultaneously with T4. Never give T4 alone -may precipitate adrenal crisis if concomitant AI (which you won't know until cortisol results return). [Endocrine Society]
Step 2 -IV levothyroxine (T4): Loading dose 200-400 mcg IV × 1, then 50-100 mcg IV daily. Must be IV -GI absorption is unreliable in myxedema (ileus, edema). Some experts add IV T3 (liothyronine) 5-20 mcg IV q8h for faster onset (T4 takes days to convert to active T3).
Step 3 -Supportive care:
Passive rewarming -warm blankets, warming to room temperature. Do NOT actively rewarm aggressively (causes vasodilation → cardiovascular collapse).
Mechanical ventilation if hypercapnic respiratory failure (CO₂ narcosis)
Vasopressors if hypotension refractory to fluids + steroids
Glucose -D50 for hypoglycemia
Step 4 -Treat the trigger: Broad-spectrum antibiotics if infection suspected (low threshold -hypothermia masks fever).
⚠ The most dangerous mistake: giving levothyroxine without cortisol coverage. T4 increases metabolic rate → increases cortisol demand → if adrenals can't respond → adrenal crisis → death.
💊 Medications
Medications
Drug
Dose
Route
Notes
Hydrocortisone
100 mg IV bolus → 50 mg IV q8h
IV
GIVE BEFORE OR WITH T4. Stress-dose steroids until AI is ruled out. Endocrine Society, 2014
Levothyroxine (Synthroid/T4)
200-400 mcg IV load → 50-100 mcg IV daily
IV
Must be IV (GI absorption unreliable). Onset: days. T4→T3 conversion impaired in critical illness.
Liothyronine (T3)
5-20 mcg IV q8h
IV
Optional -faster onset than T4. Use cautiously in elderly/cardiac patients (arrhythmia risk). Stop once clinically improving.
D50W
25g (50 mL) IV PRN
IV
For hypoglycemia (common in myxedema due to decreased gluconeogenesis).
Broad-spectrum antibiotics
Per clinical suspicion
IV
Low threshold -infection is #1 trigger and hypothermia masks fever. Empiric coverage until cultures return.
🏥 Rounds
Pimp Questions
❓ Why must you give steroids BEFORE levothyroxine in myxedema coma?
Many myxedema patients have concomitant adrenal insufficiency -either autoimmune polyendocrine syndrome (Hashimoto's + Addison's) or central hypothyroidism with secondary AI. Giving T4 increases metabolic rate → increases cortisol demand. If the adrenals can't respond → acute adrenal crisis → cardiovascular collapse → death. Always give hydrocortisone 100 mg IV first or simultaneously. [Endocrine Society]
❓ Why must levothyroxine be given IV in myxedema coma?
Myxedema causes impaired GI absorption from: (1) intestinal mucosal edema, (2) ileus/decreased motility, (3) decreased blood flow to the gut. Oral bioavailability of T4, which is already ~70% in normal patients, drops further. IV levothyroxine bypasses all of these issues and provides 100% bioavailability.
❓ Why is aggressive rewarming dangerous in myxedema coma?
Active rewarming causes peripheral vasodilation → drops preload → cardiovascular collapse in a patient who already has decreased cardiac output and contractility from hypothyroidism. Passive rewarming (warm blankets, raising room temperature) is safer. Target warming rate: 0.5°C per hour maximum.
❓ Why does myxedema coma cause hyponatremia?
Hypothyroidism causes hyponatremia through impaired free water excretion: (1) decreased cardiac output → decreased renal perfusion → increased ADH secretion, (2) decreased GFR → decreased free water delivery to collecting duct, (3) direct effect of thyroid hormone deficiency on aquaporin channels. The hyponatremia improves with T4 replacement -do NOT fluid restrict or give hypertonic saline (risks cerebral edema from too-rapid correction).
❓ What is the role of IV T3 (liothyronine) in myxedema coma?
T3 is the active thyroid hormone (T4 is a prohormone that must be converted to T3). In critical illness, peripheral T4→T3 conversion is impaired (sick euthyroid/non-thyroidal illness). IV T3 provides the active hormone directly, with onset in hours (vs days for T4). However, T3 is more likely to cause arrhythmia -use cautiously in elderly patients with cardiac disease. Most experts use combination T4 + low-dose T3.
❓ How do you differentiate myxedema coma from other causes of hypothermia + AMS?
Key clues for myxedema: (1) history of hypothyroidism or thyroidectomy scar, (2) periorbital/non-pitting edema, (3) macroglossia, (4) delayed relaxation phase of DTRs (pathognomonic), (5) hyponatremia + hypoglycemia + hypercapnia triad, (6) bradycardia disproportionate to hemodynamics. TSH and Free T4 confirm, but treatment should NOT wait for lab results if clinical suspicion is high.
Sample Presentation
Mrs. Thompson is a 82-year-old woman with known hypothyroidism (ran out of levothyroxine 2 months ago) brought from home by family for progressive lethargy × 5 days, now barely arousable. VS: T 93.6°F (34.2°C), HR 48, BP 88/52, RR 10. Exam: periorbital edema, macroglossia, dry skin, delayed DTRs, non-pitting edema of extremities. Labs: TSH > 100, Free T4 < 0.1, Na 118, glucose 52, cortisol pending, pCO₂ 68.
Key Points: Classic myxedema coma -hypothermia + AMS + bradycardia + hyponatremia + hypoglycemia + CO₂ retention in untreated hypothyroid. IMMEDIATE: hydrocortisone 100 mg IV → then T4 200-400 mcg IV. D50 for glucose. Passive rewarming. Consider intubation for hypercapnic respiratory failure (pCO₂ 68). ICU. Treat infection empirically.
Core temperature q2-4h -low-reading thermometer. Warming should be gradual. Target: rise of 0.5°C per hour maximum.
Cardiac telemetry -continuous. Watch for bradycardia, heart block, QTc prolongation, torsades. T3 replacement can cause tachycardia/arrhythmia.
TSH + Free T4 -recheck at 24-48h (T4 should be rising). TSH takes weeks to normalize -don't chase it.
AM cortisol result -if < 18 mcg/dL → confirmed AI → continue hydrocortisone. If normal → can taper steroids.
ABG -CO₂ trending (hypercapnia should improve). Intubate if pCO₂ rising or AMS worsening.
Mental status -should improve over 24-72h with treatment. If not → re-evaluate for missed trigger (sepsis, stroke).
CK trending -rhabdomyolysis from myxedema myopathy (aggressive IVF + monitor renal function)
📋 Summary
Summary
Recognize It
Decompensated hypothyroidism with a mortality of 25 to 60%. Classic picture is hypothermia plus altered mental status plus a precipitant in a patient with untreated or under-treated hypothyroidism. Do not wait for confirmatory labs: treat on clinical suspicion, because the TSH takes hours and the patient does not.
Hydrocortisone Goes First
Hydrocortisone 100 mg IV, then 50 mg IV q8h, before or with the thyroid hormone. This is the single most dangerous mistake on the page: T4 raises the metabolic rate and therefore cortisol demand, and if there is coexisting adrenal insufficiency the result is adrenal crisis and death. Continue stress-dose steroids until adrenal insufficiency is excluded.
Then Replace Thyroid Hormone Intravenously
Levothyroxine 200 to 400 mcg IV load, then 50 to 100 mcg IV daily.It must be IV because gut absorption is unreliable in a patient with bowel edema and ileus. Liothyronine 5 to 20 mcg IV q8h is optional for faster onset, since peripheral T4 to T3 conversion is impaired, but use it cautiously in the elderly and in cardiac disease where it can precipitate arrhythmia and ischemia.
Hunt the Precipitant
Infection is the number one trigger, and hypothermia masks the fever, so a normal temperature is falsely reassuring. Also look for cold exposure, sedatives and opioids, stroke, myocardial infarction, and recently stopped levothyroxine. Have a low threshold for empiric broad-spectrum antibiotics.
The Lab Pattern
TSH is very high, free T4 is low or undetectable, sodium is low (impaired free water excretion), glucose is low (reduced gluconeogenesis), and pCO₂ is high from hypoventilation. Central hypothyroidism is the exception, where the TSH is low or normal and the low free T4 is what makes the diagnosis. Also expect a raised CK and a bradycardic, low-voltage ECG.
Rewarm Passively
Blankets and a warm room only.Active external rewarming causes peripheral vasodilation and cardiovascular collapse in a patient who has no reserve. The temperature corrects as the thyroid hormone takes effect.
Correct the Sodium Slowly
The hyponatremia is dilutional and usually improves with hormone replacement and free water restriction.Do not correct rapidly: overcorrection risks osmotic demyelination, and the sodium was not the reason the patient became obtunded.
Supportive Care and Monitoring
Airway support for hypoventilation and CO₂ retention, which is a common reason these patients need intubation. D50 for hypoglycemia, cautious fluids, telemetry for bradyarrhythmia, and serial free T4 with a clinical response expected over days, not hours.
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
EMERGENTEndocrine
Pheochromocytoma
Catecholamine-secreting tumor of the adrenal medulla. Rule of 10s: 10% bilateral, 10% extra-adrenal (paraganglioma), 10% malignant, 10% familial. Alpha-block BEFORE beta-block.
🔍 Overview
Overview
Pheochromocytoma is a catecholamine-secreting neuroendocrine tumor arising from chromaffin cells of the adrenal medulla. Extra-adrenal tumors = paragangliomas (arise from sympathetic ganglia -organ of Zuckerkandl most common). Classic presentation: paroxysmal triad of headache + sweating + palpitations with hypertension. Accounts for < 1% of hypertension but must be considered in: resistant HTN, hypertensive crisis with paroxysms, adrenal incidentaloma, familial syndromes (MEN2A/2B, VHL, NF1, SDH mutations). "Rule of 10s": 10% bilateral, 10% extra-adrenal, 10% malignant, 10% pediatric, ~40% familial (higher than classically taught). The critical teaching point: Alpha-blockade MUST precede beta-blockade -unopposed alpha stimulation during beta-blockade → hypertensive crisis.
🧪 Workup
Workup
Plasma free metanephrines -best initial screening test. Sensitivity > 97%. Elevated metanephrine (from epinephrine) or normetanephrine (from norepinephrine). Draw with patient supine × 30 min. Lenders et al., Endocrine Society 2014
24-hour urine metanephrines + catecholamines -confirmatory if plasma equivocal. Also useful for monitoring post-resection.
CT abdomen/pelvis with contrast -localize adrenal mass. Pheos are typically > 3 cm, heterogeneous, > 10 HU on non-contrast CT (lipid-poor), enhance avidly.
MRI abdomen -alternative. Classic "light bulb" bright signal on T2-weighted images. Preferred in pregnancy, children, and known SDH mutations.
MIBG scan (I-123) -functional imaging for metastatic disease, extra-adrenal paragangliomas, or recurrence. If MIBG negative → FDG-PET or Ga-68 DOTATATE PET.
🚨 Management
Management
Step 1 -Alpha-blockade (start 10-14 days before surgery):
Phenoxybenzamine 10 mg BID → titrate to 20-30 mg BID (non-competitive, irreversible alpha-blocker -gold standard pre-op). Target: seated BP < 130/80 with standing SBP > 90. [Lenders et al., Endocrine Society 2014
Step 2 -Beta-blockade (ONLY after adequate alpha-blockade): Start 2-3 days before surgery or once HR > 100 on alpha-blocker. Propranolol 20-40 mg TID or atenolol 25-50 mg daily. Controls reflex tachycardia from alpha-blockade.
Step 3 -Volume expansion: High-sodium diet + liberal fluids in the 1-2 weeks pre-op. Chronic catecholamine excess → vasoconstriction → intravascular volume depletion. Volume resuscitation prevents post-resection hypotension.
Step 4 -Surgery: Laparoscopic adrenalectomy is definitive treatment. Intraoperative: expect BP swings during tumor manipulation → have nitroprusside (for hypertensive surges) and phenylephrine (for hypotension post-ligation) ready.
Hypertensive crisis management:Phentolamine 2-5 mg IV q5min (competitive alpha-blocker) or nicardipine drip. NEVER give beta-blocker alone -unopposed alpha → worse hypertension.
⚠ ALPHA BEFORE BETA -always. Beta-blockade alone removes beta-2 vasodilation → unopposed alpha-1 vasoconstriction → lethal hypertensive crisis. This is one of the most tested principles in endocrinology. Goldstein et al., 1999
Competitive alpha-1 blocker. Shorter acting than phenoxybenzamine. Less tachycardia. Some centers prefer.
Propranolol
20-40 mg TID
PO
ONLY after alpha-blockade established. Controls reflex tachycardia. Start 2-3 days before surgery.
Metyrosine
250 mg QID (max 4g/day)
PO
Tyrosine hydroxylase inhibitor -blocks catecholamine synthesis. For refractory hypertension or inoperable tumors. Sedation, EPS side effects.
Phentolamine
2-5 mg IV q5min PRN
IV
Hypertensive crisis. Competitive alpha-blocker. Fast onset. Have ready in OR during tumor manipulation.
Nicardipine
5-15 mg/hr IV
IV drip
Alternative for intraoperative/crisis BP control. Smooth, titratable.
🏥 Rounds
Pimp Questions
❓ Why must you alpha-block BEFORE beta-blocking in pheochromocytoma?
Beta-2 receptors cause vasodilation. If you block them with a beta-blocker while catecholamines are still high, you remove the vasodilatory counterbalance → unopposed alpha-1 vasoconstriction → severe hypertensive crisis. Alpha-blockade first reduces the vasoconstriction, then beta-blockade safely controls the reflex tachycardia. This is one of the most tested principles in endocrinology.
❓ What is the best initial screening test for pheochromocytoma?
Plasma free metanephrines. Sensitivity > 97% -best rule-out test. Metanephrine (from epinephrine) and normetanephrine (from norepinephrine) are continuously produced by tumor metabolism (not just during paroxysms), making them more reliable than catecholamine levels. Draw with patient supine × 30 min to avoid false positives from sympathetic activation. Lenders, 2014
❓ Why should you NOT biopsy a suspected pheochromocytoma?
Needle insertion into the tumor causes massive catecholamine release → hypertensive crisis, arrhythmia, MI, stroke, death. Diagnosis is made by biochemistry (metanephrines) + imaging. If you see an adrenal mass and pheo is in the differential, rule out pheo biochemically BEFORE any invasive procedure.
❓ What percentage of pheochromocytomas are hereditary and what syndromes should you screen for?
Up to 40% have a germline mutation (much higher than the historical "10%"). Key syndromes: MEN2A/2B (RET mutation -pheo + medullary thyroid carcinoma ± hyperparathyroidism), VHL (hemangioblastomas + renal cell + pheo), NF1 (neurofibromas + pheo), SDHx mutations (paraganglioma-pheochromocytoma syndrome -most common hereditary cause). Genetic testing recommended for ALL patients.
❓ What happens to blood glucose immediately after pheochromocytoma resection?
Hypoglycemia. Catecholamines suppress insulin secretion and stimulate gluconeogenesis/glycogenolysis. After tumor removal, the catecholamine-mediated insulin suppression is abruptly removed → rebound hyperinsulinemia → hypoglycemia. Monitor glucose q1-2h for 24h post-op. Have D50 ready.
❓ What blood pressure pattern on ambulatory monitoring suggests pheochromocytoma?
Paroxysmal hypertension with intervening normotension or hypotension. Also: loss of nocturnal dipping (BP stays elevated at night instead of the normal 10-20% drop). Some patients present with orthostatic hypotension -paradoxically, chronic catecholamine excess → receptor downregulation + volume depletion → orthostasis between paroxysms.
Clinical Examples
📋 Case 1, Classic Pheochromocytoma with Paroxysmal HTN
Patient: 38F with episodic headaches, diaphoresis, and palpitations × 4 months. Episodes last 20-30 min, occur 3-4×/week. BP 230/120 during episode, 140/88 at baseline. HR 128 during episode. Resistant to 3 antihypertensives.
Phenoxybenzamine 10 mg PO BID → titrate to goal BP < 130/80 seated with orthostatic SBP > 90 standing
High-salt diet + liberal fluids (catecholamine-induced volume contraction, must volume-expand before surgery)
Add beta-blocker (propranolol 20 mg TID) ONLY after adequate alpha-blockade (3-5 days minimum)
NEVER give beta-blocker first → unopposed alpha stimulation → hypertensive crisis
Laparoscopic adrenalectomy after 10-14 days of medical optimization
Teaching point: Alpha before beta, the cardinal rule of pheo management. Beta-blockers without alpha-blockade remove beta-2 vasodilation, leaving unopposed alpha vasoconstriction, causing severe hypertensive crisis.
📋 Case 2, Pheo Crisis in the OR
Patient: 52M undergoing cholecystectomy. During insufflation, sudden BP 280/160, HR 160, SVT on telemetry. No known pheo history. Incidental 2.8 cm adrenal mass seen on pre-op CT but not investigated.
Key findings: Intraoperative catecholamine crisis, triggered by abdominal insufflation compressing an undiagnosed pheochromocytoma. Surgical manipulation is the classic precipitant of pheo crisis.
Management:
Phentolamine 2-5 mg IV bolus q5min until BP controlled (fast-acting alpha-blocker for crisis)
Nicardipine drip 5-15 mg/hr as alternative/adjunct for BP control
Esmolol drip for rate control ONLY after alpha-blockade initiated
Abort the primary surgery, do not manipulate the adrenal gland
Post-op: confirm diagnosis with plasma metanephrines, plan formal pheo workup and staged adrenalectomy after medical optimization
Teaching point: Adrenal incidentalomas > 1 cm should always have plasma metanephrines checked before any surgery. An undiagnosed pheo in the OR has a mortality rate of up to 80% if unrecognized.
📋 Case 3, Hereditary Paraganglioma (SDH Mutation)
Patient: 24M with HTN and headaches. Father had bilateral pheos at age 30. Plasma normetanephrine 980 pg/mL. MRI: 2.2 cm left extra-adrenal retroperitoneal mass (paraganglioma). Right adrenal normal.
Key findings: Young age + family history + extra-adrenal location = high suspicion for hereditary syndrome. ~40% of pheos/paragangliomas have germline mutations (SDHx, VHL, MEN2, NF1).
Management:
Genetic testing: SDHx panel, VHL, RET (MEN2), NF1, mandatory for all pheos/paragangliomas per Endocrine Society
MIBG scintigraphy or Ga-68 DOTATATE PET/CT to rule out multifocal/metastatic disease
Alpha-blockade → surgical resection of paraganglioma
Lifelong annual screening with plasma metanephrines (high recurrence/new primary risk with SDH mutations)
Screen first-degree relatives if mutation confirmed
Teaching point: All pheos/paragangliomas should get genetic testing, 40% are hereditary. SDHx mutations carry the highest malignancy risk (up to 40% for SDHB). Extra-adrenal location and young age are red flags for hereditary syndromes.
Sample Presentation
Mr. Park is a 42-year-old man presenting with episodic headaches, diaphoresis, and palpitations × 6 months. Episodes last 15-30 min, occur 2-3 times per week, associated with severe hypertension (240/130 during episodes, 155/95 baseline). Home medications: amlodipine 10 mg, lisinopril 40 mg, HCTZ 25 mg (resistant HTN). Labs: plasma normetanephrine 1850 pg/mL (> 4× ULN). CT abdomen: 4.2 cm right adrenal mass, heterogeneous enhancement, 38 HU on non-contrast.
Key Points: Classic pheo -paroxysmal triad + resistant HTN + markedly elevated normetanephrine + lipid-poor adrenal mass. Start phenoxybenzamine 10 mg BID immediately. Titrate over 10-14 days. High-sodium diet for volume expansion. Add propranolol ONLY after adequate alpha-blockade. Genetic testing. Laparoscopic adrenalectomy after medical optimization.
Pre-op checklist: BP controlled × 7-14 days, mild orthostatic hypotension present, HR 60-80, no ECG ischemia, no new ST changes × 2 weeks
Intraoperative: arterial line mandatory. Expect BP surges during tumor manipulation → phentolamine/nitroprusside ready. Expect hypotension after tumor ligation → volume + phenylephrine/vasopressin ready.
Post-op glucose -hypoglycemia is common after tumor removal (catecholamines were suppressing insulin → insulin rebound). Monitor glucose q1-2h × 24h.
Post-op plasma metanephrines -at 2-4 weeks. Should normalize. If persistently elevated → residual/metastatic disease.
Annual biochemical screening -lifelong (recurrence risk ~5-10%). More frequent if genetic syndrome.
Genetic counseling -all patients. Screen first-degree relatives if mutation found.
📋 Summary
Summary
Suspect It
Classic triad: episodic headache, sweating and palpitations with paroxysmal hypertension. Also consider it in resistant hypertension, an incidentally found adrenal mass, hypertension in a young patient, or a hypertensive crisis during anesthesia or a procedure.
Rule of 10s
10% bilateral, 10% extra-adrenal (paraganglioma), 10% malignant, 10% familial. The familial fraction is in truth much higher than 10% in modern series, so refer for genetic testing: MEN2, von Hippel-Lindau, NF1 and the SDH mutations all present this way.
Screen Biochemically First
Plasma free metanephrines, sensitivity above 97%, or 24-hour urine fractionated metanephrines. Metanephrines beat catecholamines because they are secreted continuously by the tumor, so they do not depend on catching a paroxysm. Draw supine after 30 min of rest, and remember acetaminophen, tricyclics, levodopa and labetalol all cause false positives.
Image Only After the Biochemistry Is Positive
CT or MRI of the abdomen once the labs confirm. Imaging first leads to chasing incidentalomas. MIBG or Ga-68 DOTATATE when the tumor is not found, is multifocal, or metastatic disease is suspected.
The Rule That Gets Tested and Kills Patients
Alpha-blockade before beta-blockade, always. Giving a beta blocker first removes beta-2 mediated vasodilation and leaves unopposed alpha-1 vasoconstriction, which precipitates a lethal hypertensive crisis.
Preoperative Preparation
Phenoxybenzamine 10 mg BID titrated to 20 to 30 mg BID, started 10 to 14 days before surgery (doxazosin 2 to 8 mg daily is the competitive, shorter-acting alternative). Add a beta blocker such as propranolol only after alpha-blockade is established, to control reflex tachycardia. Metyrosine blocks catecholamine synthesis in refractory cases.
Liberalize Salt and Fluid Before the Operation
Chronic catecholamine excess leaves the patient profoundly volume-contracted. A high-sodium diet and generous fluids during alpha-blockade re-expand the intravascular space, which is what prevents the catastrophic hypotension that follows tumor devascularization.
Intraoperative and Long-Term
Have phentolamine 2 to 5 mg IV q5min or a nicardipine infusion ready for surges during tumor handling, and norepinephrine ready for the crash after the vein is clamped. Recheck metanephrines 2 to 6 weeks post-operatively to confirm cure, then screen annually for life, since recurrence and metachronous tumors occur years later.
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
EMERGENTEndocrine
Inpatient Hypoglycemia
The most common inpatient endocrine emergency. Every episode of glucose < 70 requires intervention. Recurrent hypoglycemia increases mortality independent of the cause.
🔍 Overview
Overview
Inpatient hypoglycemia (glucose < 70 mg/dL) affects up to 10-30% of hospitalized diabetic patients and is independently associated with increased mortality, longer LOS, and ICU transfer.NICE-SUGAR, NEJM 2009 Classified as: Level 1 (54-70 mg/dL, alert), Level 2 (< 54, clinically significant), Level 3 (severe, requiring assistance from another person). Most common causes: (1) insulin-food mismatch (holding meals while continuing insulin), (2) renal insufficiency (reduced insulin clearance), (3) reduced PO intake (NPO, nausea, surgery), (4) medication errors. Key principle: every hypoglycemic event is preventable and deserves root cause analysis. The attending will ask "why did this happen and what did you change?"
🧪 Workup
Workup
Confirm with venous glucose -point-of-care glucometers are less accurate at low ranges. Whipple's triad: symptoms + low glucose + symptom resolution with glucose correction.
Review insulin/secretagogue doses -#1 cause. Check timing of last insulin dose vs last meal. Basal insulin too high? Sliding scale overlapping with scheduled dose?
Medication reconciliation -sulfonylureas (long-acting, especially in CKD), insulin dose errors, fluoroquinolones (rare), pentamidine, beta-blockers (mask symptoms)
NPO status -was patient made NPO for procedure while basal insulin continued?
Nutrition assessment -decreased PO intake, skipped meals, vomiting, new tube feed interruption
If non-diabetic unexplained hypoglycemia: insulin level + C-peptide + proinsulin + sulfonylurea screen (draw DURING hypoglycemia). High insulin + high C-peptide = endogenous hyperinsulinism (insulinoma). High insulin + low C-peptide = exogenous insulin. High C-peptide + positive SU screen = sulfonylurea use.
Cortisol -if adrenal insufficiency suspected (especially if recurrent hypoglycemia with hypotension)
🚨 Management
Management
Unable to eat / AMS / NPO:D50W 25g (50 mL) IV push → recheck in 15 min → repeat PRN → start D10W drip at 50-100 mL/hr if recurrent
No IV access: Glucagon 1 mg IM/SQ. Causes nausea -position on side.
Prevent recurrence (most important step):
Reduce basal insulin by 20-40% if the episode occurred overnight or fasting ADA Standards of Care, 2026
Hold or reduce prandial insulin if patient is eating less than usual or NPO
Discontinue sulfonylurea in CKD/AKI (long half-life → recurrent hypoglycemia for 24-72h)
Adjust sliding scale -reduce correction factor if consistently hypoglycemic
Ensure meal delivery before prandial insulin -coordinate with nursing
Hold prandial insulin if patient is NPO -only continue basal (and reduce by 20-50%)
Document root cause analysis in the note -attendings expect it.
Sulfonylurea-induced hypoglycemia (especially glipizide/glyburide in CKD) can recur for 24-72 hours even after initial correction. These patients need D10 drip + hourly glucose checks + admission for observation. Octreotide 50 mcg SQ q6h can reduce insulin secretion in refractory cases.
💊 Medications
Medications
Drug
Dose
Route
Notes
D50W (Dextrose 50%)
25g (50 mL) IV push
IV
First-line for severe/unable to eat. Repeat q15min PRN. Causes phlebitis -use large bore IV.
D10W drip
50-100 mL/hr
IV
For recurrent hypoglycemia (especially sulfonylurea-induced). Prevents repeated D50 pushes.
Glucagon
1 mg IM/SQ
IM/SQ
If no IV access. Mobilizes hepatic glycogen. Ineffective if glycogen-depleted (alcoholics, liver failure). Causes nausea.
Octreotide (Sandostatin)
50 mcg SQ q6h
SQ
For sulfonylurea-induced hypoglycemia refractory to D10. Suppresses insulin release from pancreatic beta cells. McLaughlin, 2000
Oral glucose (juice/tabs)
15-20g fast-acting carbs
PO
First-line if alert + able to swallow. Follow with complex carbs. Recheck at 15 min.
🏥 Rounds
Pimp Questions
❓ Why is sulfonylurea-induced hypoglycemia more dangerous than insulin-induced?
Sulfonylureas (especially glyburide and glipizide) have long half-lives (12-24h+) that are prolonged further in CKD. Unlike insulin which has a predictable duration, sulfonylureas can cause recurrent hypoglycemia for 24-72 hours even after initial correction. This is why patients need D10 drip + observation, not just a D50 push and discharge. Octreotide can help by suppressing insulin release.
❓ How do you differentiate insulinoma from exogenous insulin administration?
Draw labs during hypoglycemia:Insulinoma: high insulin + high C-peptide + high proinsulin (endogenous production). Exogenous insulin: high insulin + LOW C-peptide (exogenous insulin suppresses endogenous production). Sulfonylurea use: high insulin + high C-peptide + positive sulfonylurea screen. C-peptide is the key differentiator because commercial insulin preparations do not contain C-peptide.
❓ When should you use octreotide for hypoglycemia?
Sulfonylurea-induced hypoglycemia refractory to D10 drip. Octreotide (somatostatin analog) suppresses insulin secretion from pancreatic beta cells. Dose: 50 mcg SQ q6h. It is NOT useful for insulin-induced hypoglycemia (the problem is exogenous insulin, not endogenous secretion). Consider in: recurrent hypoglycemia despite D10, glipizide/glyburide with CKD, intentional sulfonylurea ingestion. McLaughlin, 2000
❓ What insulin adjustments should you make after an inpatient hypoglycemic event?
Root cause analysis + immediate order changes: (1) If overnight/fasting hypo → reduce basal insulin by 20-40%. (2) If post-prandial hypo → reduce prandial/correction dose. (3) If NPO → hold prandial, reduce basal by 20-50%. (4) If on sulfonylurea + AKI/CKD → STOP sulfonylurea. (5) If multiple sliding scale corrections overlapping → simplify regimen. Document the analysis and changes in your note -this is expected by attendings.
❓ Why does glucagon not work in alcoholic or liver failure patients?
Glucagon works by mobilizing hepatic glycogen stores (glycogenolysis). In chronic alcoholics and liver failure patients, glycogen stores are depleted (alcohol inhibits gluconeogenesis + poor nutritional intake). Without glycogen to break down, glucagon is ineffective. These patients need IV dextrose (D50 or D10 drip) -there is no alternative.
❓ What is the "rule of 15" for hypoglycemia?
For alert patients who can eat: give 15 grams of fast-acting carbohydrate (4 oz juice, 3-4 glucose tabs) → recheck glucose in 15 minutes → repeat if still < 70. Once glucose > 70, follow with a complex carbohydrate snack to prevent recurrence. Simple and effective -but only works if the patient can protect their airway and swallow safely.
Sample Presentation
Mr. Garcia is a 68-year-old man with T2DM on glargine 40 units + glipizide 10 mg BID, admitted for pneumonia, found to have fingerstick glucose of 38 at 3 AM. Diaphoretic, confused. Last meal was dinner at 5 PM (ate 50% of tray). Cr 2.4 (baseline 1.2). Received full sliding scale correction of 6 units at 9 PM for glucose of 220.
Key Points: Three contributors: (1) Glipizide in AKI (reduced clearance → prolonged hypoglycemic effect), (2) reduced PO intake, (3) sliding scale correction on top of basal + sulfonylurea. Immediate: D50 25g IV → start D10 drip. Prevent: STOP glipizide (always in AKI). Reduce glargine by 40% (24 units). Reduce sliding scale. This patient needs q1h glucose checks × 24h because glipizide will continue to cause hypoglycemia.
Fingerstick glucose q15 min until glucose > 100 and stable
Then q1h × 4h to ensure no recurrence (especially with long-acting insulin or sulfonylureas)
Resume regular glucose monitoring (AC/HS or q6h) once stable
Review all insulin orders after ANY hypoglycemic event -this is the intern's most important action
Notify attending of any Level 2 (< 54) or Level 3 (severe) hypoglycemia
Glucose below 70 mg/dL is the intervention threshold; below 54 is clinically significant hypoglycemia.Recurrent hypoglycemia raises mortality independently of whatever caused it, so it is treated as an event to be investigated, not a number to be corrected and forgotten.
Treat by Route the Patient Can Use
Alert and able to swallow → 15 to 20 g of fast-acting carbohydrate, then recheck in 15 min and follow with a complex carbohydrate or the next meal so it does not simply recur. Obtunded or unable to eat → D50W 25 g IV push, repeatable every 15 min. No IV access → glucagon 1 mg IM.
Glucagon Fails in the Patients Who Need It Most
It works by mobilizing hepatic glycogen, so it does nothing when the stores are empty.Expect it to fail in alcohol use disorder, malnutrition, prolonged fasting and advanced liver disease, which are exactly the populations that present with severe hypoglycemia. Get IV access and give dextrose.
Sulfonylureas Recur for Days
Glipizide and especially glyburide, above all in chronic kidney disease, cause hypoglycemia that recurs for 24 to 72 h after the first correction.A single amp of D50 and a normal recheck is a trap: these patients need a D10 infusion, hourly glucose checks and admission for observation, and octreotide 50 mcg SC q6h when they keep dropping despite dextrose, because it suppresses the insulin release the drug keeps driving.
Find the Cause, Not Just the Number
Review every glucose-lowering agent and its timing against meals, then look for the change that precipitated it: a missed or held meal, a new NPO order, acute kidney injury reducing insulin clearance, sepsis, adrenal insufficiency, liver failure, or steroids being tapered off.
The Commonest Inpatient Causes Are Iatrogenic
Insulin given for a meal the patient did not eat, a correction scale stacked on top of scheduled insulin, sudden NPO status, and failure to reduce doses when the kidney fails.These are order-writing problems, so the fix is in the orders: match mealtime insulin to actual intake, and reduce the dose when renal function falls.
Draw the Critical Sample Before You Treat
In an unexplained hypoglycemia with no diabetes, get insulin, C-peptide, proinsulin, beta-hydroxybutyrate and a sulfonylurea screen while the glucose is still low.High insulin with high C-peptide means endogenous, an insulinoma or a sulfonylurea, which the drug screen separates. High insulin with low C-peptide means exogenous insulin. Once the sugar is corrected the sample is uninterpretable.
Prevent the Next One
Document the episode and change something. Reduce or reschedule the offending dose, loosen the glycemic target in the elderly and in advanced kidney disease, move off glyburide, and give bedtime snacks where nocturnal events are the pattern. Also warn about hypoglycemia unawareness: repeated episodes blunt the adrenergic warning symptoms, so the next event presents as confusion or seizure with no preceding shakiness.
RoundsRx Infographic Series · #123 · Renal & Metabolic · PDF 153 KB
Text version
One-Pager
Inpatient Hypoglycemia
Treat, prevent, document
Immediate
Alert: 15g PO carbs → recheck 15 min. AMS/NPO: D50 25g IV → repeat PRN → D10 drip. No IV: glucagon 1 mg IM.
Prevent Recurrence
Reduce basal 20-40%. STOP sulfonylurea in AKI. Hold prandial if NPO. Ensure meal before prandial insulin. SU hypo: D10 drip + octreotide + observe 24-72h.
Workup If Non-Diabetic
Draw DURING hypo: insulin, C-peptide, proinsulin, sulfonylurea screen. High insulin + low C-peptide = exogenous. High insulin + high C-peptide = insulinoma or SU.
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
EMERGENTEndocrine
Hypocalcemia
Ionized calcium < 4.4 mg/dL or corrected total Ca < 8.5. Emergent when symptomatic (tetany, seizures, QTc prolongation). Most common causes: hypoparathyroidism (post-surgical), vitamin D deficiency, CKD.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Overview
Hypocalcemia = ionized Ca < 4.4 mg/dL or corrected total Ca < 8.5 mg/dL. Correct total calcium for albumin: corrected Ca = total Ca + 0.8 × (4 − albumin). Always check ionized calcium in critically ill patients (more accurate with hypoalbuminemia, acid-base disturbances). Most common causes: (1) Post-surgical hypoparathyroidism (after thyroidectomy/parathyroidectomy -most common inpatient cause), (2) Vitamin D deficiency (most common overall), (3) CKD (decreased 1,25-OH vitamin D production), (4) Hypomagnesemia (impairs PTH secretion AND causes PTH resistance -MUST correct Mg first), (5) Acute pancreatitis (calcium saponification), (6) Massive transfusion (citrate chelates calcium). Symptoms correlate with rate of decline more than absolute level.
🧪 Workup
Workup
Ionized calcium -most accurate, especially in ICU (not affected by albumin or pH). < 4.4 mg/dL = hypocalcemia.
Corrected total calcium -if ionized not available. Corrected = total + 0.8 × (4 − albumin).
Albumin -for correction. Low albumin → falsely low total Ca (but ionized is normal).
Magnesium -MUST check. Mg < 1.5 → impairs PTH secretion AND causes end-organ PTH resistance. Hypocalcemia will NOT correct until Mg is repleted.
25-OH vitamin D -< 20 ng/mL = deficiency. Most common cause of hypocalcemia worldwide.
1,25-dihydroxy vitamin D -low in CKD (can't hydroxylate 25-OH to active form). Also low in hypoparathyroidism (PTH stimulates 1-alpha-hydroxylase).
Phosphate -high PO₄ + low Ca = hypoparathyroidism or CKD. Low PO₄ + low Ca = vitamin D deficiency.
ECG -prolonged QTc (risk of torsades de pointes). Also: ST changes mimicking ischemia.
BMP, Cr -CKD assessment
🚨 Management
Management
EMERGENT (symptomatic or iCa < 3.2):
Calcium gluconate 10% 1-2 g (10-20 mL) IV over 10-20 min -first-line, and safe through a peripheral IV. Repeat until symptoms resolve.
Calcium chloride 10% 1 g IV over 5-10 min through a central line only -it carries 3× the elemental calcium (272 mg/g vs 93), but extravasation causes tissue necrosis.
Follow the bolus with an infusion -5-10 g calcium gluconate in 500 mL D5W over 12-24h. A bolus alone wears off within hours and the tetany returns.
Continuous ECG monitoring -the prolonged QT is what precedes the arrhythmia, so it is the parameter that tells you the correction is working.
Do NOT run calcium in the same line as bicarbonate or phosphate -they precipitate. Flush between, or use a separate line.
Correct MAGNESIUM FIRST: Hypocalcemia will NOT respond to calcium supplementation if Mg is depleted. MgSO₄ 2-4g IV over 20-60 min.
Chronic management:
Vitamin D deficiency: Ergocalciferol 50,000 IU PO weekly × 8-12 wk → maintenance 1000-2000 IU daily
Hypoparathyroidism: Calcitriol 0.25-2 mcg PO BID + calcium carbonate 1-3g TID with meals. Target: low-normal Ca (8-8.5) to avoid hypercalciuria.
CKD: Calcitriol (active vitamin D) + phosphate binders. Correct 25-OH vitamin D if deficient. Manage per CKD-MBD guidelines.
Post-thyroidectomy "hungry bone syndrome": After parathyroidectomy for hyperparathyroidism, bones rapidly take up calcium → severe, prolonged hypocalcemia. May need IV calcium drip × days + high-dose oral calcium + calcitriol. Check Ca q6h post-op. Witteveen et al., 2013
💊 Medications
Medications
Drug
Dose
Route
Notes
Calcium gluconate 10%
1-2g (10-20 mL) IV over 10-20 min
IV
First-line IV. Can use peripheral IV. 93 mg elemental Ca per gram. Repeat PRN. Follow with drip.
Calcium chloride 10%
1g (10 mL) IV over 5-10 min
IV (central)
3× more elemental Ca than gluconate (272 mg/g). Central line ONLY -tissue necrosis risk. For arrest/severe tetany.
Ca gluconate drip
5-10g in 500 mL D5W over 12-24h
IV
Continuous infusion for sustained correction. Do NOT mix with bicarb (precipitates).
MgSO₄
2-4g IV over 20-60 min
IV
Correct Mg BEFORE Ca. Hypomagnesemia causes PTH resistance → Ca won't correct.
Calcitriol
0.25-2 mcg PO BID
PO
Active vitamin D. For hypoparathyroidism + CKD. Fast onset (1-2 days). Monitor Ca closely (narrow window).
Ergocalciferol (D2)
50,000 IU weekly × 8-12 wk
PO
Vitamin D deficiency repletion. Then maintenance 1000-2000 IU daily.
Calcium carbonate
500-1500 mg elemental TID with meals
PO
Chronic replacement. Requires gastric acid for absorption (take with food, not with PPI).
🏥 Rounds
Pimp Questions
❓ Why must you correct magnesium before calcium?
Hypomagnesemia causes hypocalcemia through TWO mechanisms: (1) Impaired PTH secretion -Mg is required for PTH release from the parathyroid gland. (2) End-organ PTH resistance -Mg is needed for PTH to activate its receptor in bone and kidney. The result: giving calcium without correcting Mg is futile -the Ca will continue to drop because PTH is dysfunctional. Always check and correct Mg first.
❓ What is the difference between calcium gluconate and calcium chloride?
Calcium gluconate: 93 mg elemental Ca per gram. Can go through peripheral IV. Lower tissue necrosis risk. First-line for most situations. Calcium chloride: 272 mg elemental Ca per gram (3× more). Requires central line -causes severe tissue necrosis if peripheral IV infiltrates. Reserved for cardiac arrest, severe tetany, or when rapid correction needed via central access.
❓ What is Trousseau sign and why is it more specific than Chvostek sign?
Trousseau sign: inflate BP cuff above systolic × 3 min → carpal spasm (metacarpophalangeal flexion + interphalangeal extension + thumb adduction = "obstetrician's hand"). Specificity ~94% for hypocalcemia. Chvostek sign: tap facial nerve → ipsilateral facial muscle twitch. Specificity only ~30% -present in ~10% of normocalcemic individuals. Trousseau is far more reliable clinically.
❓ What is "hungry bone syndrome"?
After parathyroidectomy for severe hyperparathyroidism, the chronically suppressed bones suddenly have normal PTH levels → rapid uptake of calcium, phosphate, and magnesium into demineralized bone → severe, prolonged hypocalcemia (can last days to weeks). Risk factors: high pre-op PTH, high pre-op ALP, vitamin D deficiency, high pre-op Ca. Treatment: aggressive IV calcium drip + high-dose oral calcium + calcitriol. May need 10+ grams of elemental calcium per day initially.
❓ How does the phosphate level help differentiate causes of hypocalcemia?
High PO₄ + low Ca: hypoparathyroidism (PTH normally causes renal phosphate wasting -without PTH, PO₄ rises) or CKD (can't excrete PO₄). Low PO₄ + low Ca: vitamin D deficiency (both Ca and PO₄ are low due to impaired gut absorption) -PTH is appropriately elevated (secondary hyperparathyroidism), which causes phosphaturia. Phosphate is a crucial clue that most people forget to check.
❓ Why should you NOT mix IV calcium with bicarbonate?
Calcium and bicarbonate form calcium carbonate precipitate (insoluble chalk) in the IV tubing. This can cause tubing occlusion and -more dangerously -if the precipitate enters the bloodstream, it can cause embolic tissue damage. Always flush lines between calcium and bicarb. Same applies to calcium + phosphate-containing solutions.
Clinical Examples
📋 Case 1, Post-Thyroidectomy Hypocalcemia
Patient: 48F, POD1 from total thyroidectomy for papillary thyroid carcinoma. Perioral tingling, hand cramping. HR 94, BP 130/78. Positive Trousseau and Chvostek signs. iCa 3.4 mg/dL, Mg 1.9, PO₄ 5.4, PTH < 5. QTc 520 ms.
Key findings: Post-surgical hypoparathyroidism, most common cause of acute hypocalcemia in hospital. Low PTH + low Ca + high PO₄ = classic pattern. QTc prolongation → arrhythmia risk.
Management:
Calcium gluconate 2g IV over 20 min → start continuous drip (6g in 500 mL D5W at 50 mL/hr)
Calcitriol 0.5 mcg PO BID (active vitamin D, bypasses PTH-dependent 1-alpha-hydroxylation)
Oral calcium carbonate 1-2g TID with meals (long-term replacement)
Check iCa q4-6h until stable on drip. Target iCa > 4.0 mg/dL
Telemetry for QTc monitoring, torsades risk if QTc > 500 ms
Teaching point: Use calcitriol (not ergocalciferol) in hypoparathyroidism, without PTH, the kidney cannot 1-alpha-hydroxylate 25-OH vitamin D to its active form. Calcitriol is already active and works within hours.
📋 Case 2, Severe Symptomatic Hypocalcemia with Seizure
Patient: 34F with CKD stage 5 (not yet on dialysis). Generalized tonic-clonic seizure in ED. iCa 2.8 mg/dL, Mg 1.2, PO₄ 8.4, PTH 380 (elevated). Cr 7.8. QTc 560 ms.
Key findings: Severe hypocalcemia from CKD: elevated PO₄ (can't excrete), elevated PTH (secondary hyperparathyroidism but can't make active vitamin D), and hypomagnesemia (impairs PTH action). Seizure = emergent.
Management:
Calcium gluconate 4g IV over 20 min (2 amps in code-like urgency for seizure)
Magnesium sulfate 2g IV over 1h, MUST correct Mg first or Ca will not stay up
Continuous calcium drip after bolus, iCa q2h until > 4.0
Sevelamer 800 mg TID with meals (phosphate binder, high PO₄ complexes with Ca, worsening hypocalcemia)
Calcitriol 0.25-0.5 mcg daily. Expedite dialysis initiation (nephrologist)
Teaching point: In CKD hypocalcemia, lowering phosphate is as important as giving calcium. High PO₄ × Ca product > 55 → metastatic calcification (soft tissue calcium deposits). Always correct Mg concurrently, it's futile to give calcium without adequate Mg.
📋 Case 3, Vitamin D Deficiency Hypocalcemia
Patient: 72F from nursing home, minimal sun exposure, poor nutrition. Progressive fatigue, muscle cramps, diffuse bone pain. Ca 7.8, albumin 3.8 (corrected Ca 8.0), PO₄ 2.0 (low), PTH 185 (elevated), 25-OH vitamin D 6 ng/mL (severely deficient). ALP 240 (elevated).
Key findings: Vitamin D deficiency → low Ca AND low PO₄ (both malabsorbed). PTH appropriately elevated (secondary hyperparathyroidism). Elevated ALP = increased bone turnover (osteomalacia). This is the classic pattern: low Ca, low PO₄, high PTH, high ALP.
Management:
Ergocalciferol (D2) 50,000 IU PO weekly × 8-12 weeks, then 1000-2000 IU daily maintenance
Oral calcium carbonate 1-1.5g daily (gut absorption impaired without vitamin D, will improve as D repletes)
Recheck 25-OH vitamin D at 8-12 weeks, target > 30 ng/mL
Monitor Ca, PO₄, PTH, PTH should normalize as vitamin D repletes
DEXA scan once vitamin D replete (osteomalacia artificially lowers T-score)
Teaching point: The phosphate level is the key differentiator: low PO₄ = vitamin D deficiency (both Ca and PO₄ malabsorbed, PTH causes phosphaturia). High PO₄ = hypoparathyroidism or CKD (PTH normally wastes phosphate, without PTH, PO₄ rises).
Sample Presentation
Mrs. Liu is a 55-year-old woman, post-op day 1 from total thyroidectomy for papillary thyroid carcinoma. Nurse calls for perioral tingling and hand cramping. VS: HR 92, BP 128/78. Exam: positive Trousseau sign, positive Chvostek sign. Labs: iCa 3.6 mg/dL (low), Mg 1.8, PO₄ 5.2 (high), PTH < 5 (low). ECG: QTc 510 ms.
Key Points: Post-surgical hypoparathyroidism (most common cause of acute hypocalcemia in hospital). Low PTH + low Ca + high PO₄ = classic. QTc prolonged → emergent. Give calcium gluconate 2g IV over 20 min → start drip. Start calcitriol 0.5 mcg BID + calcium carbonate 1g TID. Check iCa q6h. This may be transient (parathyroids stunned) or permanent.
Ionized calcium q4-6h during IV replacement (q2h if critically symptomatic)
ECG -QTc monitoring. QTc should shorten as Ca normalizes. Torsades risk if QTc > 500 ms.
Mg level -recheck after repletion. Must remain > 1.5 for Ca correction to work.
Post-thyroidectomy: ionized Ca q6h × 24-48h. Albumin-corrected Ca unreliable post-surgery (fluid shifts). ATA Thyroidectomy Guidelines, 2020
Phosphate -trending helps differentiate causes. Falling PO₄ + rising Ca on treatment = responding to vitamin D/PTH replacement.
Chvostek and Trousseau signs -clinical bedside assessment. Chvostek: tap facial nerve → ipsilateral facial twitch. Trousseau: BP cuff inflated above systolic × 3 min → carpal spasm (more specific).
Cr -calcium + vitamin D therapy can worsen renal function. Monitor in CKD patients.
📋 Summary
Summary
Confirm It Is Real
Check ionized calcium, or correct the total for albumin: add 0.8 mg/dL for every 1 g/dL the albumin sits below 4.Hypoalbuminemia is the commonest cause of a low total calcium with a completely normal ionized level, and treating that number is treating an artifact. Alkalosis also lowers ionized calcium at any given total, which is why hyperventilation causes tetany.
Recognize the Emergency
Tetany, carpopedal spasm, laryngospasm, seizures and a prolonged QTc mean treat now. Chvostek and Trousseau signs support it (Trousseau is the more specific). Laryngospasm and arrhythmia are what kill, so symptomatic hypocalcemia is treated before the workup is complete.
Give IV Calcium the Right Way
Calcium gluconate 1 to 2 g IV over 10 to 20 min is first line and can go through a peripheral line.Calcium chloride has 3 times the elemental calcium but is central line only, because extravasation causes tissue necrosis. Follow the bolus with an infusion, 5 to 10 g of gluconate in 500 mL D5W over 12 to 24 h, since a bolus alone wears off within hours. Never run calcium in the same line as bicarbonate or phosphate: it precipitates.
Fix the Magnesium First
Hypomagnesemia causes both PTH resistance and impaired PTH secretion, so the calcium will not correct until the magnesium does. Give magnesium sulfate 2 to 4 g IV. This is the single commonest reason refractory hypocalcemia stays refractory, and it is often missed in alcohol use disorder, diuretic use and proton pump inhibitor therapy.
Work Out the Mechanism From the PTH
Low or inappropriately normal PTH → hypoparathyroidism, most often post-surgical, or magnesium-related. High PTH → the gland is responding appropriately, so look for vitamin D deficiency, chronic kidney disease, or pseudohypoparathyroidism. Check magnesium, phosphate, creatinine and 25-hydroxyvitamin D at the same time.
Match the Vitamin D to the Problem
Calcitriol 0.25 to 2 mcg PO BID for hypoparathyroidism and CKD, because both lack renal 1-alpha-hydroxylase activity and cannot activate plain vitamin D. Ergocalciferol 50,000 IU weekly for 8 to 12 weeks for simple vitamin D deficiency, then 1,000 to 2,000 IU daily maintenance.
Anticipate the High-Risk Situations
Post-thyroidectomy and post-parathyroidectomy hungry bone syndrome: the skeleton takes up calcium rapidly, producing severe, prolonged hypocalcemia that may need a calcium infusion for days plus high-dose oral calcium and calcitriol. Also expect it after massive transfusion (citrate chelation), in pancreatitis, in tumor lysis syndrome, and with bisphosphonates or denosumab given to a vitamin D deficient patient.
Do Not Chase Calcium in Tumor Lysis
Treat the hypocalcemia of tumor lysis syndrome only if the patient is symptomatic. Giving calcium while the phosphate is high drives calcium-phosphate precipitation in the kidney and worsens the acute kidney injury. Lower the phosphate first.
RoundsRx Infographic Series · #163 · Renal & Metabolic · PDF 145 KB
Text version
One-Pager
Hypocalcemia
Correct Mg first. Always.
Emergent Treatment
Ca gluconate 1-2g IV over 10-20 min (peripheral OK). Follow with drip 5-10g/24h. Ca chloride via central only (3× more elemental Ca). MgSO₄ 2-4g IV if Mg < 1.5.
Diagnostic Branch
PTH low → hypoparathyroidism (post-surgical, autoimmune). PTH high → secondary (vitamin D deficiency, CKD). PO₄ helps: high PO₄ = hypopara/CKD. Low PO₄ = vitamin D deficiency.
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
RoundsRx Licensed Content - Unauthorized Use Prohibited
EndocrineICU
Diabetes Insipidus
Massive free water loss from ADH deficiency (central) or resistance (nephrogenic). Classic: polyuria (> 3L/day), polydipsia, dilute urine (osm < 300), rising serum Na⁺.
🔍 Overview
Overview
Diabetes insipidus (DI) is the inability to concentrate urine, causing massive free water loss. Two types: Central DI -deficient ADH production from posterior pituitary (post-pituitary surgery #1, head trauma, tumors, idiopathic, Sheehan syndrome). Nephrogenic DI -kidneys resistant to ADH (lithium #1 cause, hypercalcemia, hypokalemia, tubulointerstitial disease, medications). Key features: polyuria > 3L/day (can exceed 15-20L), dilute urine (osm < 300), hypernatremia if free water access is restricted. Triphasic response post-pituitary surgery: DI (days 1-5) → SIADH (days 5-10, transient ADH release from dying neurons) → permanent DI (if > 80% of ADH neurons destroyed). This is a dangerous pattern -the SIADH phase can cause fatal hyponatremia if you're giving DDAVP for the initial DI phase.
🧪 Workup
Workup
Serum Na⁺ + serum osmolality -Na usually > 145, osm > 295. If patient has free water access, Na may be normal (compensated by polydipsia).
Urine osmolality + urine specific gravity -Uosm < 300 mOsm/kg (often < 100) in the presence of elevated serum osm = inappropriately dilute = DI. Sp. gravity < 1.005.
Water deprivation test -gold standard for diagnosis (rarely needed in obvious cases). [Miller et al., 1970 Withhold fluids, monitor urine osm and body weight. In DI, urine remains dilute despite rising serum osm. Then give DDAVP 2 mcg IV: if Uosm rises > 50% → central DI (responds to exogenous ADH). If no response → nephrogenic DI.
Copeptin level -newer test, co-secreted with ADH. Low copeptin + hyperosmolality = central DI. Fenske et al., 2018
MRI pituitary -if central DI suspected. Look for absent posterior pituitary bright spot (normal T1 hyperintensity from ADH-containing vesicles).
Calcium + potassium -hypercalcemia and hypokalemia cause nephrogenic DI
Lithium level -most common drug cause of nephrogenic DI (40% of chronic lithium users develop some concentrating defect)
Desmopressin (DDAVP) -10-40 mcg daily intranasal, 0.1-0.4 mg BID PO, or 1-4 mcg q12h IV. Selective V2 agonist, so unlike vasopressin it has no vasopressor effect and will not raise blood pressure or cause splanchnic ischemia.
Titrate to the lowest dose that controls thirst and nocturia, and allow a period of breakthrough polyuria before each dose. Continuous full antidiuresis in a patient who keeps drinking is what causes iatrogenic hyponatremia.
Let the patient drink to thirst -an intact thirst mechanism protects the sodium far better than any dosing schedule. The dangerous patient is the one who cannot drink (intubated, obtunded, adipsic), who needs measured free water replacement instead.
Find the cause -pituitary MRI, and check the other pituitary axes. Isolated central DI is uncommon, and a missed cortisol deficiency can mask DI until steroids are replaced and the polyuria suddenly appears.
Monitor Na⁺ at least daily while titrating (q4-6h in the acute post-operative setting) -both under- and over-treatment show up in the sodium before the patient reports symptoms.
Nephrogenic DI:
Remove cause -stop lithium (if possible), correct hypercalcemia, correct hypokalemia
Thiazide diuretics (paradoxical effect) -hydrochlorothiazide 25 mg daily. Causes mild volume depletion → increased proximal Na⁺/H₂O reabsorption → less water delivered to collecting duct → reduced urine volume. Counterintuitive but effective.
Amiloride 5-10 mg daily -specifically for lithium-induced NDI. Blocks lithium entry through ENaC in collecting duct.
NSAIDs (indomethacin) -reduce prostaglandin-mediated antagonism of ADH. Adjunct, not first-line.
ICU management of acute DI: D5W or free water via NG tube. Match UOP with replacement (mL for mL replacement initially). DDAVP 1-2 mcg IV q12h. BMP q4-6h.
💊 Medications
Medications
Drug
Dose
Route
Notes
DDAVP (desmopressin)
10-40 mcg daily (nasal); 0.1-0.4 mg BID (PO); 1-4 mcg q12h (IV)
IN/PO/IV
Central DI treatment. V2 receptor agonist. No vasopressor effect (unlike native ADH). Risk: hyponatremia from overcorrection.
Hydrochlorothiazide (Microzide)
25 mg daily
PO
Nephrogenic DI. Paradoxical antidiuresis via proximal volume depletion. Monitor K⁺.
Amiloride
5-10 mg daily
PO
Lithium-induced NDI specifically. Blocks ENaC → blocks lithium entry into principal cells.
Indomethacin
25-50 mg TID
PO
Adjunct for NDI. Reduces prostaglandin antagonism of ADH. GI/renal side effects.
D5W
Per free water deficit
IV
Free water replacement. Replace 50% of deficit in first 24h. Limit Na correction ≤ 10-12 mEq/24h.
🏥 Rounds
Pimp Questions
❓ How do you distinguish central from nephrogenic DI?
DDAVP challenge: give DDAVP 2 mcg IV and measure urine osm. Central DI: Uosm rises > 50% (kidneys respond to exogenous ADH because the problem is lack of production). Nephrogenic DI: Uosm does NOT rise (< 10% increase -kidneys are resistant to ADH). Clinical clues: post-pituitary surgery → central. On lithium → nephrogenic.
❓ What is the triphasic response after pituitary surgery?
Phase 1 (days 1-5): DI -surgical damage → decreased ADH release → polyuria. Phase 2 (days 5-10): SIADH -dying posterior pituitary neurons release stored ADH → water retention → hyponatremia. Phase 3 (day 10+): Permanent DI if > 80% of ADH neurons destroyed. The SIADH phase is dangerous -if you're giving DDAVP from phase 1, continuing it into phase 2 → severe hyponatremia. Must stop DDAVP when UOP drops.
❓ Why do thiazides help nephrogenic DI? Isn't that paradoxical?
Thiazides block NaCl reabsorption in the distal tubule → mild volume depletion → activates proximal tubule Na⁺/H₂O reabsorption → less water delivered to the collecting duct → reduced total urine volume. The collecting duct (where ADH acts) receives less filtrate to work with. It's a volume-depletion-mediated effect, not a direct ADH effect. Reduces UOP by 30-50%.
❓ Why is amiloride specifically useful in lithium-induced nephrogenic DI?
Lithium enters principal cells of the collecting duct via the epithelial sodium channel (ENaC). Once inside, lithium interferes with aquaporin-2 insertion (the water channel that ADH activates). Amiloride blocks ENaC → blocks lithium entry → prevents lithium from impairing the ADH signaling cascade. This is specific to lithium-induced NDI -amiloride does not help other causes of NDI.
❓ What is the free water deficit formula?
FWD = TBW × [(Na/140) − 1]. TBW = 0.6 × weight (kg) for men, 0.5 × weight for women. Example: 70 kg man, Na 160 → FWD = 42 × [(160/140) − 1] = 42 × 0.14 = 6 liters. Replace 50% in first 24h, rest over next 24-48h. Limit Na correction ≤ 10-12 mEq/24h to avoid cerebral edema (brain adapted to hyperosmolality with idiogenic osmoles).
Sample Presentation
Mr. Ahmed is a 45-year-old man, post-op day 2 from transsphenoidal resection of pituitary macroadenoma. Overnight UOP 4.2L in 8 hours (525 mL/hr). Clear, dilute urine. Na 152 (was 139 pre-op), serum osm 312, urine osm 89, urine SG 1.002. Patient reports extreme thirst.
Key Points: Post-surgical central DI -massive polyuria with dilute urine and rising Na. Start DDAVP 1 mcg IV q12h. Replace free water deficit with D5W. Monitor Na q4h. Watch for triphasic response -stop DDAVP immediately if UOP drops and Na starts falling (SIADH phase).
Urine output hourly -in ICU/acute DI. UOP > 250 mL/hr = uncontrolled DI → needs DDAVP or more free water.
Post-pituitary surgery: UOP + Na q4-6h × 72h minimum. Watch for triphasic response -DI phase (days 1-5) may transition to SIADH (days 5-10). Stop DDAVP if UOP drops and Na falls.
Lithium level -if continuing lithium with amiloride, monitor both
📋 Summary
Summary
The Picture
Polyuria above 3 L/day, polydipsia, dilute urine with osmolality below 300, and a rising serum sodium.Central DI is failure to make ADH; nephrogenic DI is failure to respond to it.A conscious patient with free access to water keeps the sodium nearly normal, so a markedly high sodium means the patient could not drink, which is usually the sicker situation.
Confirm It Is Really DI
Simultaneous serum and urine osmolality: a high or high-normal serum osmolality with inappropriately dilute urine makes the diagnosis.Exclude an osmotic diuresis first, above all hyperglycemia, and also mannitol, high-protein feeds and post-obstructive or post-ATN diuresis, all of which produce large urine volumes for entirely different reasons.
Desmopressin Separates the Two Types
Water deprivation followed by desmopressin: central DI concentrates the urine, nephrogenic DI does not.Copeptin measurement is replacing the classic deprivation test in many centers because it is faster and safer. Never water-deprive an already hypernatremic patient: they have made the diagnosis for you.
Central DI: Give Desmopressin
10 to 40 mcg daily intranasally, 0.1 to 0.4 mg BID orally, or 1 to 4 mcg q12h IV.It is a selective V2 agonist with no vasopressor effect, unlike vasopressin. Causes: post-neurosurgery or pituitary surgery, head injury, tumor, infiltrative disease, and brain death.Get a pituitary MRI and check the other pituitary axes, since isolated DI is uncommon.
Nephrogenic DI: Fix the Cause, Then Use the Paradox
Stop the offending drug where possible, and correct hypercalcemia and hypokalemia, both of which cause reversible resistance. Thiazides work paradoxically: hydrochlorothiazide 25 mg daily causes mild volume depletion, which increases proximal sodium and water reabsorption and so reduces delivery to the distal nephron and cuts urine output. Add a low-sodium diet, which amplifies the same effect, and indomethacin as an adjunct.
Lithium Has Its Own Answer
Amiloride 5 to 10 mg daily blocks ENaC, which is the channel lithium uses to enter the collecting duct cell. That makes it the specific agent for lithium-induced nephrogenic DI, and it can be continued while the lithium is continued if the psychiatric indication requires it. The defect may be irreversible after long exposure, so it is worth catching early.
Correct the Sodium at the Right Speed
Replace with free water, D5W or oral water, and correct chronic hypernatremia by no more than 10 mEq/L per 24 h.Replace about half the calculated deficit in the first 24 h and reassess. Faster correction causes cerebral edema, because the brain has generated osmoles it cannot shed quickly. Add ongoing urinary losses to the calculation, which is what the formulas leave out and why patients fall behind.
The Post-Neurosurgical Triphasic Response
DI for a few days, then a period of SIADH as stored ADH is released from the degenerating posterior pituitary, then permanent DI.The middle phase is where patients get into trouble, since desmopressin continued through it causes profound hyponatremia. Check sodium at least twice daily post-operatively and be prepared to stop the drug rather than simply continuing a standing order.
ACTH-dependent: MRI pituitary (60% show adenoma). If MRI negative or equivocal → inferior petrosal sinus sampling (IPSS) with CRH stimulation (gold standard to confirm pituitary vs ectopic).
ACTH-independent: CT adrenals (adenoma vs carcinoma vs bilateral hyperplasia)
Exogenous Cushing's: Taper steroids as disease allows. Never stop abruptly (adrenal suppression → adrenal crisis). Taper over weeks-months depending on duration.
Cushing's disease (pituitary):Transsphenoidal surgery (TSS) -first-line. Cure rate 65-90% for microadenomas. Post-op: patients develop adrenal insufficiency (need hydrocortisone replacement until HPA axis recovers -months to years). If surgery fails: repeat TSS, radiation, bilateral adrenalectomy, or medical therapy.
Adrenal adenoma: Laparoscopic adrenalectomy -curative. Post-op AI (contralateral adrenal suppressed).
❓ What is inferior petrosal sinus sampling (IPSS)?
Gold standard to differentiate pituitary vs ectopic ACTH. Catheters placed in bilateral inferior petrosal sinuses (drain the pituitary). Compare petrosal ACTH to peripheral ACTH before and after CRH stimulation. Central-to-peripheral ACTH ratio ≥ 2 (basal) or ≥ 3 (post-CRH) = pituitary source. If ratio < 2 → ectopic ACTH. Indicated when MRI is negative or equivocal.
❓ Why do patients develop adrenal insufficiency after successful pituitary surgery?
Chronic ACTH excess from the pituitary adenoma → chronic cortisol excess → suppresses CRH and the normal corticotrophs (negative feedback). When the adenoma is removed, the remaining normal pituitary tissue is atrophied and cannot produce adequate ACTH → secondary adrenal insufficiency. HPA axis recovery takes 6-18 months. Patients need hydrocortisone replacement until the axis recovers.
❓ What features help distinguish Cushing's from simple obesity?
Cushing's-specific features: (1) Proximal muscle weakness (can't rise from chair without arms -obesity alone doesn't cause this), (2) wide (> 1 cm) violaceous striae (obesity has narrow, pink striae), (3) easy bruising + skin thinning, (4) new-onset diabetes + HTN + osteoporosis in a young person, (5) facial plethora. Weight gain in Cushing's is classically central with thin extremities (muscle wasting). Obese patients have more generalized fat distribution.
❓ Why can't you monitor cortisol levels on mifepristone?
Mifepristone is a glucocorticoid receptor antagonist -it blocks the receptor, not cortisol production. In fact, cortisol levels rise on mifepristone (loss of negative feedback → ACTH increases → cortisol increases). You must monitor clinical response (glucose, weight, striae, weakness) and urinary cortisol will be misleadingly HIGH. This makes dose titration challenging.
Clinical Examples
📋 Case 1, Cushing's Disease (Pituitary Adenoma)
Patient: 36F with 25 lb central weight gain, new T2DM, HTN, wide purple striae, easy bruising, and proximal weakness × 10 months. Moon facies, dorsocervical fat pad. No exogenous steroids.
If TSS fails or recurrence: repeat surgery, radiation, bilateral adrenalectomy, or medical therapy (ketoconazole, osilodrostat)
Teaching point: After successful TSS, cortisol should be undetectable (< 2 mcg/dL), this confirms cure. Patients will need glucocorticoid replacement for 6-18 months until the suppressed HPA axis recovers.
📋 Case 2, Ectopic ACTH (Small Cell Lung Cancer)
Patient: 58M smoker with rapid-onset HTN, hypokalemia (K⁺ 2.4), hyperglycemia (glucose 380), and proximal weakness over 6 weeks. Hyperpigmented. No classic Cushingoid body habitus (too rapid for fat redistribution).
Key findings: ACTH 280 pg/mL (markedly elevated), UFC > 1000 mcg. High-dose DST: no suppression. CT chest: 3 cm RLL mass with hilar lymphadenopathy. Consistent with ectopic ACTH from SCLC.
Ketoconazole 200 mg TID or metyrapone to rapidly lower cortisol (medical adrenalectomy)
Oncology: staging and treatment of SCLC (chemo ± radiation)
If refractory hypercortisolism: bilateral adrenalectomy (definitive but causes permanent AI)
VTE prophylaxis, extreme hypercortisolism is profoundly prothrombotic
Teaching point: Ectopic ACTH presents differently from pituitary Cushing's: rapid onset, severe hypokalemia, very high ACTH (> 200), and hyperpigmentation. The patient often looks sick, not Cushingoid, because fat redistribution takes months.
📋 Case 3, Iatrogenic Cushing's (Exogenous Steroids)
Patient: 65F with RA on prednisone 20 mg daily × 2 years. Moon facies, central obesity, osteoporosis (T-score -3.2), T2DM, recurrent oral candidiasis. Rheumatologist requests steroid taper advice.
Key findings: Iatrogenic Cushing syndrome, the #1 cause of Cushing's overall. Chronic exogenous steroids have suppressed the HPA axis. Abrupt discontinuation → adrenal crisis.
Management:
Slow taper: reduce by 2.5 mg q2-4 weeks until physiologic dose (5 mg prednisone ≈ 20 mg hydrocortisone)
Below physiologic dose: switch to hydrocortisone 10-15 mg/day and taper by 2.5 mg q2-4 weeks
ACTH stimulation test before final discontinuation, if cortisol > 18 mcg/dL, axis has recovered
DMARD optimization for RA (methotrexate, biologics) to enable steroid discontinuation
Address complications: DEXA + bisphosphonate for osteoporosis, diabetes management, PCP prophylaxis if > 20 mg/day
Teaching point: Exogenous steroids at any dose for > 3 weeks can suppress the HPA axis. Always taper, never stop abruptly. Patients on chronic steroids need stress-dose steroids for surgery or acute illness until axis recovery is confirmed.
Sample Presentation
Ms. Rivera is a 38-year-old woman with new-onset diabetes, HTN, 30 lb weight gain (central), wide purple striae on abdomen, and proximal weakness × 8 months. No exogenous steroid use. Labs: 24h UFC 380 mcg (3× ULN), late-night salivary cortisol 0.85 mcg/dL (elevated), 1 mg DST cortisol 12.4 (failed suppression). ACTH 68 pg/mL (elevated). MRI pituitary: 8 mm left-sided adenoma.
Key Points: Classic Cushing's disease -confirmed hypercortisolism (2/3 tests positive), ACTH-dependent, pituitary adenoma on MRI. Refer for TSS. Pre-op: control hyperglycemia (insulin), VTE prophylaxis (hypercoagulable), PCP prophylaxis if severely Cushingoid, address osteoporosis. Post-op: expect AI (start hydrocortisone replacement).
AM cortisol + ACTH -post-TSS: check day 1-3. Undetectable cortisol (< 2) = successful surgery. Patient needs hydrocortisone replacement.
Morning cortisol off replacement -periodically to assess HPA axis recovery (may take 6-18 months post-surgery). Cosyntropin stim test when cortisol approaches normal.
LFTs q2-4 weeks on ketoconazole
ECG (QTc) on ketoconazole, osilodrostat
Blood glucose -Cushing's causes insulin resistance. May need insulin during active disease. Hyperglycemia also a major side effect of pasireotide.
DEXA scan -osteoporosis screening (cortisol excess → bone loss)
MRI pituitary annually × 5 years post-TSS (recurrence monitoring)
📋 Summary
Summary
Ask About Steroids First
Exogenous glucocorticoids are by far the commonest cause of Cushing syndrome.Ask about oral, inhaled, topical, intra-articular and over-the-counter preparations, since injected and topical steroids are routinely forgotten in the history. Exogenous disease has a suppressed ACTH and a suppressed cortisol, so identifying it stops the workup before any expensive test.
Recognize the Discriminating Features
Weight gain, moon facies and central obesity are common and non-specific.The features that actually discriminate are proximal muscle weakness, wide purple striae over 1 cm, easy bruising and facial plethora, along with unexplained osteoporosis, new hypertension and new diabetes in a young patient.
Screen With Two of Three Tests
Late-night salivary cortisol, 1 mg overnight dexamethasone suppression, or 24-hour urinary free cortisol.Two abnormal tests are needed before proceeding, because any single test has false positives. Exclude pseudo-Cushing first: alcohol use disorder, severe depression, poorly controlled diabetes and obesity all produce mild biochemical abnormalities without the disease.
Then Measure ACTH to Split the Differential
Suppressed ACTH means an adrenal source, adenoma, carcinoma or bilateral hyperplasia, so image the adrenals. Normal or high ACTH means an ACTH-dependent cause, either pituitary (Cushing disease, about 80% of endogenous cases) or ectopic. The ACTH is the branch point of the entire workup and comes after confirmation, not before.
Distinguish Pituitary From Ectopic Carefully
Pituitary MRI plus high-dose dexamethasone suppression and CRH stimulation: a pituitary source usually suppresses and responds, an ectopic source usually does not. Inferior petrosal sinus sampling is the gold standard and is needed because pituitary incidentalomas are common and a microadenoma may not be visible on MRI at all. Ectopic ACTH is suggested by rapid onset, severe hypokalemic alkalosis and marked hyperpigmentation, most often from small cell lung cancer or a bronchial carcinoid.
Surgery Is the Definitive Treatment
Transsphenoidal resection for Cushing disease, adrenalectomy for an adrenal source, and resection of the tumor in ectopic disease.Bilateral adrenalectomy is the last resort for refractory disease and commits the patient to lifelong replacement, with a risk of Nelson syndrome afterwards.
Medical Therapy Is a Bridge
Steroidogenesis inhibitors: ketoconazole 200 to 400 mg BID to TID (monitor liver tests), metyrapone, or osilodrostat with QTc monitoring. Pasireotide for Cushing disease, with hyperglycemia as the main limitation. Mifepristone blocks the receptor and is approved for Cushing-associated hyperglycemia, but cortisol levels then become uninterpretable for monitoring. Mitotane for adrenal carcinoma.
Expect Adrenal Insufficiency After Cure
The contralateral or residual tissue has been chronically suppressed and takes months to a year to recover, so every successfully treated patient needs glucocorticoid replacement with a slow taper and stress-dose education. Steroid withdrawal syndrome, with arthralgia, fatigue and depression despite adequate replacement, is expected and is not a reason to raise the dose. Meanwhile treat the comorbidities: hypertension, diabetes, osteoporosis, hypercoagulability (these patients are at real VTE risk) and opportunistic infection risk.
Adrenal CrisisDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' DiseaseHypocalcemia
Endocrine
Hyperthyroidism / Graves' Disease
Graves' = most common cause of hyperthyroidism. TSI-mediated thyroid stimulation. Treatment: thionamides, RAI, or surgery. Know when each is preferred.
TSH -suppressed (< 0.1 mIU/L). Most sensitive initial test.
Free T4 + Free T3 -both elevated in overt hyperthyroidism. T3 thyrotoxicosis: suppressed TSH + normal FT4 + elevated FT3 (early Graves' or toxic nodule).
TSI (thyroid-stimulating immunoglobulins) or TRAb (TSH receptor antibodies) -positive in Graves'. Specific. Can be used to confirm diagnosis without RAIU in pregnancy or when RAIU unavailable.
Thionamide for 12-18 months -methimazole 10-30 mg daily is first-line (once-daily dosing, more potent, fewer serious adverse effects). PTU 100-200 mg TID only for first-trimester pregnancy, thyroid storm, or methimazole allergy, because PTU carries a risk of fulminant hepatic failure. Remission after a full course is roughly 30-50%, and is most likely with mild disease, a small goiter and a low TRAb titer, so check TRAb before stopping to predict relapse. Warn every patient that fever or sore throat means stop the drug and get an urgent white cell count -agranulocytosis occurs in 0.2-0.5% and routine monitoring does not predict it.
Radioactive iodine (I-131) -definitive, simple and outpatient. Permanent hypothyroidism is the expected outcome, not a complication, so plan levothyroxine replacement and check thyroid function at 6-8 weeks. Avoid in pregnancy and breastfeeding (fetal thyroid ablation) and in moderate-to-severe orbitopathy, which it can worsen; if it must be used, give steroid cover.
Surgery (near-total thyroidectomy) -for a large compressive goiter, suspected malignancy, severe orbitopathy, or pregnancy where drugs fail. Fastest and most certain control. Render euthyroid first and give SSKI for 7-10 days pre-op to reduce gland vascularity and bleeding. Risks are recurrent laryngeal nerve injury and hypoparathyroidism, so check calcium post-operatively.
Thyroiditis: Self-limited (4-8 weeks). Beta-blockers only. NSAIDs or prednisone for pain (subacute). Thionamides are USELESS (no new hormone being made -just release of preformed).
💊 Medications
Medications
Drug
Dose
Route
Notes
Methimazole (Tapazole)
10-30 mg daily → titrate
PO
First-line thionamide. Once daily dosing. Agranulocytosis (0.2-0.5%) -check CBC if fever/sore throat. Teratogenic in 1st trimester.ATA, 2016
PTU (propylthiouracil)
100-200 mg TID
PO
ONLY for: 1st trimester pregnancy, thyroid storm, methimazole allergy. TID dosing. FDA black box: severe hepatotoxicity (fulminant liver failure). Also blocks T4→T3.
Propranolol
20-40 mg TID-QID
PO
Symptom control. Also blocks peripheral T4→T3 conversion. Use in ALL hyperthyroid patients.
Wolff-Chaikoff effect -acute iodine load transiently blocks thyroid hormone release. Pre-op preparation for thyroidectomy. Give AFTER thionamide established.
Cholestyramine
4g TID
PO
Adjunct -binds thyroid hormone in gut, reduces enterohepatic recirculation. Used in severe thyrotoxicosis.
🏥 Rounds
Pimp Questions
❓ Why is methimazole preferred over PTU?
Methimazole advantages: once-daily dosing (vs TID for PTU), lower hepatotoxicity risk, more consistent pharmacokinetics, no FDA black box warning. PTU is preferred ONLY in: (1) first trimester pregnancy (methimazole causes aplasia cutis + choanal atresia), (2) thyroid storm (PTU also blocks T4→T3 conversion), (3) methimazole allergy/intolerance. After first trimester, switch back to methimazole. ATA, 2016
❓ How does RAIU differentiate causes of thyrotoxicosis?
High uptake (diffuse) = Graves'. High uptake (focal) = toxic adenoma or toxic MNG. Low/absent uptake = thyroiditis (preformed hormone leaking from damaged gland -no new synthesis), exogenous thyroid hormone, or iodine excess. This is the key test because treatment differs fundamentally: thionamides work for Graves'/toxic nodules (blocking new synthesis) but are useless in thyroiditis (nothing being synthesized).
❓ Why can RAI worsen Graves' ophthalmopathy?
RAI-induced thyroid destruction releases thyroid antigens that cross-react with orbital tissue (TSH receptor is expressed in orbital fibroblasts). This triggers an immune flare targeting the orbits → worsening inflammation, proptosis, diplopia. Risk is highest in smokers and those with pre-existing active ophthalmopathy. Prevention: prednisone 0.3-0.5 mg/kg starting the day of RAI × 4-6 weeks taper in moderate-risk patients. Avoid RAI entirely in moderate-severe active ophthalmopathy.
❓ What is the most feared side effect of thionamides and how do you screen for it?
Agranulocytosis (ANC < 500) -incidence 0.2-0.5%, usually within first 90 days. Can be fatal if not recognized. DO NOT do routine CBC monitoring (too insensitive, can develop rapidly between checks). Instead: educate the patient to present immediately for fever, sore throat, or mouth sores → get STAT CBC. If ANC < 500 → stop thionamide permanently, admit, broad-spectrum antibiotics, G-CSF, switch to non-thionamide therapy (RAI or surgery).
❓ How do you manage hyperthyroidism in pregnancy?
First trimester: PTU (methimazole is teratogenic). Second/third trimester: switch to methimazole (PTU hepatotoxicity risk). Use the lowest effective dose -aim for FT4 at upper limit of normal (mild maternal hyperthyroidism is safer than fetal hypothyroidism from overtreatment). RAI is absolutely contraindicated in pregnancy (ablates fetal thyroid). Check TSI/TRAb in third trimester -if elevated, neonatal hyperthyroidism possible. ATA, 2016
Sample Presentation
Ms. Patel is a 32-year-old woman with 3 months of 15 lb weight loss despite increased appetite, palpitations, tremor, anxiety, and heat intolerance. Exam: HR 108, diffusely enlarged thyroid with bruit, lid lag, mild proptosis bilateral, fine tremor. Labs: TSH < 0.01, FT4 4.8 (elevated), FT3 12 (elevated), TSI positive. RAIU: diffusely elevated at 65% (normal 10-30%).
Key Points: Classic Graves' disease -suppressed TSH, elevated FT4/FT3, positive TSI, diffusely elevated RAIU. Start propranolol for symptoms. Discuss 3 treatment options. Methimazole 20 mg daily for 12-18 month trial is reasonable first-line (32-year-old who may want pregnancy). Check CBC + LFTs baseline. Ophthalmology referral for proptosis.
TFTs (TSH + FT4) q4-6 weeks during thionamide titration. TSH may remain suppressed for months -use FT4 to guide dose adjustments initially.
CBC -if fever or sore throat on thionamides (agranulocytosis: ANC < 500). Get STAT CBC. Incidence 0.2-0.5%, usually within first 90 days.
LFTs -baseline + periodic on PTU. Discontinue if transaminases > 3× ULN. PTU hepatotoxicity can be fulminant.
TSI/TRAb -if monitoring for remission after thionamide trial. Persistently elevated = high relapse risk. Check before stopping thionamide at 12-18 months.
Post-RAI: TFTs q4-6 weeks × 6 months. Hypothyroidism typically develops by 6-12 weeks. Start levothyroxine when TSH rises.
Ophthalmopathy assessment -active inflammation = orbital CT/MRI, refer ophthalmology. IV methylprednisolone for moderate-severe active orbitopathy [EUGOGO].
📋 Summary
Summary
Confirm the Diagnosis Before Treating
Suppressed TSH with a raised free T4 (and free T3, since T3-predominant disease exists).Graves disease is the commonest cause and is driven by thyroid-stimulating immunoglobulin. Diffuse goiter, orbitopathy and pretibial myxedema make it clinical; otherwise check TSI or TRAb.
Separate Hyperthyroidism From Thyroiditis
Radioactive iodine uptake distinguishes them and it changes the entire treatment.High, diffuse uptake = Graves, the gland is making hormone. Low uptake = thyroiditis or exogenous hormone, the gland is leaking preformed hormone. Thionamides do nothing in thyroiditis, which is self-limited and treated with beta blockade and NSAIDs.
Beta Blockade for Everyone Symptomatic
Propranolol 20 to 40 mg TID to QID. It controls tremor, tachycardia and anxiety immediately, and at higher doses it also blocks peripheral conversion of T4 to T3. It is the fastest-acting part of the regimen, since thionamides take weeks.
Methimazole Is First Line, With Two Exceptions
Methimazole 10 to 30 mg daily, once-daily dosing, fewer side effects and more potent. Use propylthiouracil only in the first trimester of pregnancy, in thyroid storm, and in methimazole allergy: methimazole is teratogenic (aplasia cutis, choanal atresia) in early pregnancy, and PTU blocks peripheral conversion which helps in storm. PTU otherwise carries a risk of fulminant hepatic failure, which is why it is no longer the default.
Warn About Agranulocytosis Explicitly
Agranulocytosis occurs in 0.2 to 0.5% and it presents as fever and sore throat.Tell the patient to stop the drug and get an urgent white cell count if that happens; treating it as a viral pharyngitis is how these patients die. Routine serial counts do not predict it, so the instruction matters more than the monitoring.
Choose the Definitive Treatment
Radioactive iodine is definitive and simple, and permanent hypothyroidism is the expected outcome, not a complication. Avoid it in pregnancy, breastfeeding and moderate to severe orbitopathy, which it can worsen. Surgery for a large compressive goiter, suspected malignancy, severe orbitopathy or pregnancy where drugs fail. Continued thionamide therapy for 12 to 18 months gives remission in a minority, mostly those with small goiters and low antibody titers.
Orbitopathy Runs Its Own Course
It does not track the thyroid function tests and it does not resolve when the biochemistry is corrected.Smoking is the strongest modifiable risk factor, so cessation is a therapeutic intervention here. Severe active disease is treated with IV steroids or teprotumumab; radioactive iodine can be given with steroid cover if it must be used.
Do Not Miss Storm
Fever, tachycardia out of proportion, agitation or delirium, heart failure and GI symptoms in a hyperthyroid patient.Order is essential: thionamide first, then iodine at least 1 hour later, because giving iodine first supplies substrate for hormone synthesis. Add a beta blocker, steroids, and treat the precipitant, usually infection or surgery.
RoundsRx Infographic Series · #189 · Renal & Metabolic · PDF 149 KB
Text version
One-Pager
Hyperthyroidism
Graves', Toxic Nodule, Thyroiditis
RAIU Pattern
Diffuse high = Graves'. Focal hot = toxic adenoma. Patchy = MNG. Low = thyroiditis/exogenous/iodine.
Treatment Choice
Methimazole first-line (12-18 mo). RAI if definitive needed (causes hypothyroidism). Surgery for large goiter/nodule/ophthalmopathy. Thyroiditis: beta-blockers only.
Trials
ATA Hyperthyroidism Guidelines 2016 · EUGOGO (ophthalmopathy management)
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hypocalcemia
Endocrine
Primary Aldosteronism
Most common cause of secondary hypertension. Screen: ARR (aldosterone-to-renin ratio). Confirm: salt loading. Localize: adrenal CT + adrenal vein sampling. Cause: adenoma (Conn's) vs bilateral hyperplasia.
🔍 Overview
Overview
Primary aldosteronism (PA) is autonomous aldosterone production independent of the renin-angiotensin system. It is the most common cause of secondary hypertension, affecting 5-13% of all hypertensive patients and up to 20% of resistant HTN. Two main subtypes: bilateral adrenal hyperplasia (BAH, ~60%) and aldosterone-producing adenoma (APA / Conn's syndrome, ~35%). The distinction matters because APA is surgically curable while BAH is treated medically. Classic lab triad: hypertension + hypokalemia + metabolic alkalosis, but most patients are normokalemic (hypokalemia is present in only 30-50%). PA causes cardiovascular damage disproportionate to BP -higher rates of stroke, MI, AF, and HF than essential HTN at the same BP level, because aldosterone drives myocardial and vascular fibrosis directly, not just through the blood pressure. That is why finding it matters even when the BP looks controlled.
🧪 Workup
Workup
📋 What changed in the 2025 Endocrine Society guideline (a complete update of the 2016 guideline)
Screen every patient with hypertensionCHANGED 2025 -not only the high-risk groups below. 2016 restricted screening to resistant HTN, hypokalemia, adrenal incidentaloma, and early-onset or severe HTN. The rationale is that PA affects 5 to 14% of hypertensives in primary care and up to 30% in referral centers, and was being detected in almost nobody.
Confirmatory testing is now selectiveCHANGED 2025 -reserved for an intermediate-probability screen in a patient who actually wants to pursue surgery. If the plan is medical therapy regardless, a suppression test rarely changes management.
Spironolactone is preferred over other MRAs on cost and availability, and MRAs are preferred over ENaC inhibitors such as amiloride and triamterene NEW 2025.
Add a dexamethasone suppression test when an adenoma is foundNEW 2025, to detect co-secreted cortisol, which changes peri-operative steroid cover.
Who to screen:2025: every patient with hypertensionCHANGED. The highest-yield groups remain resistant HTN (≥ 3 drugs), HTN + hypokalemia (spontaneous or diuretic-induced), HTN + adrenal incidentaloma, HTN onset < 40, severe HTN (≥ 160/100), obstructive sleep apnea, atrial fibrillation out of proportion to risk factors, and a family history of early stroke or PA -so start there if you cannot screen everyone at once.
Step 2 -Confirmatory test (suppress aldosterone), now selective:skip it entirely when there is spontaneous hypokalemia + undetectable renin + PAC > 20 ng/dL, which is diagnostic on its own, and skip it when the patient is going to be treated medically regardless. Reserve it for an intermediate screen in a surgical candidate.
IV saline infusion test: 2L NS over 4h → measure PAC. If PAC > 10 ng/dL post-infusion = confirmed (aldosterone should suppress but doesn't).
Oral salt loading: High-sodium diet × 3 days → 24h urine aldosterone. > 12 mcg/24h = confirmed.
Fludrocortisone suppression test: Fludrocortisone 0.1 mg q6h × 4 days → PAC remains > 6. Most specific but rarely used (cumbersome, risk of hypokalemia).
Step 3 -Subtype differentiation + localization:
CT adrenals -look for unilateral adenoma (> 1 cm). BUT: CT is wrong 38% of the time (nonfunctioning incidentaloma mimics APA, or microadenoma is missed).
Adrenal vein sampling (AVS) -gold standard to lateralize aldosterone production. Lateralization ratio ≥ 4:1 = unilateral source → surgery. Essential for ALL surgical candidates unless: age < 35 with clear > 1 cm unilateral adenoma + normal contralateral.
🚨 Management
Management
Unilateral APA (Conn's):Laparoscopic adrenalectomy -biochemical cure in 94%, but only 37% become normotensive off all antihypertensives; another 47% improve PASO, 2017. Counsel the patient before surgery that the operation cures the hormone problem far more reliably than it cures the blood pressure. Pre-op: control BP and K⁺ with MRA (spironolactone or eplerenone). Post-op: monitor K⁺ (contralateral zona glomerulosa may be suppressed → transient hypoaldosteronism).
Bilateral adrenal hyperplasia:Medical therapy with mineralocorticoid receptor antagonists (MRA):
Spironolactone 25-100 mg daily -most effective MRA. Anti-androgenic side effects: gynecomastia (up to 50% in men), menstrual irregularity, decreased libido. PATHWAY-2, 2015
Eplerenone 25-50 mg BID -selective MRA with far fewer anti-androgenic effects, so it is the switch when gynecomastia appears. Roughly half as potent per mg, and it must be dosed twice daily because of its shorter half-life.
Monitoring K⁺ on MRA: Hyperkalemia risk, especially with CKD or ACEi/ARB combo. Check K⁺ + Cr at 1 week, 4 weeks, then q3-6 months.
Monitoring
Setting
What to check, and when
Why
Starting or uptitrating an MRA
K⁺ and creatinine at 1 week and 4 weeks, then every 3 to 6 months once stable
MRAs cause hyperkalemia, and the risk multiplies with CKD or a concurrent ACE inhibitor or ARB. A creatinine rise of up to 30% is expected as the hyperfiltration comes off.
After adrenalectomy
K⁺ and BP within the first week; stop or halve the MRA and potassium supplements on the day of surgery
The contralateral zona glomerulosa has been chronically suppressed, so transient hypoaldosteronism with hyperkalemia is common in the first weeks. Continuing the MRA into that window is the classic post-op error.
Cure assessment
Renin and aldosterone at 3 months, with BP and drug count
Use the PASO definitions: biochemical cure is the rule, clinical cure is not. A persistently suppressed renin suggests residual disease.
On long-term medical therapy
Renin should become detectable, plus BP and K⁺
An unsuppressed renin indicates adequate mineralocorticoid receptor blockade. If renin stays suppressed the dose is too low, and the cardiovascular risk of aldosterone excess persists even with a normal BP.
💊 Medications
Medications
Drug
Dose
Route
Notes
Spironolactone (Aldactone)
25-100 mg daily
PO
First-line MRA. Most effective for PA. Anti-androgenic SE (gynecomastia 50%, sexual dysfunction). Monitor K⁺. PATHWAY-2, 2015
Eplerenone (Inspra)
50-100 mg BID
PO
Selective MRA. Fewer hormonal SE. More expensive. May need higher doses than spironolactone.
Amiloride
5-10 mg daily
PO
Alternative for K⁺-sparing if MRA intolerance. Less effective for BP lowering than spironolactone.
Nifedipine (Procardia)
30-60 mg daily
PO
Add-on antihypertensive. Does not interfere with ARR screening.
🏥 Rounds
Pimp Questions
❓ Why can't you rely on CT alone to decide on surgery for primary aldosteronism?
CT is wrong in up to 38% of cases. Reasons: (1) Nonfunctioning adrenal incidentalomas are common (5-10% of adults have them) -a visible nodule may NOT be the aldosterone source. (2) Microadenomas (< 1 cm) may be the true source but invisible on CT. (3) Bilateral hyperplasia can have an asymmetric appearance mimicking a unilateral adenoma. Adrenal vein sampling (AVS) is the gold standard -it directly measures aldosterone from each adrenal vein. Endocrine Society, 2016
❓ What medications must you hold before ARR screening and for how long?
Spironolactone and eplerenone: hold × 6 weeks (major interference). Diuretics: hold × 4 weeks (cause hypokalemia → suppress aldosterone; stimulate renin). Beta-blockers: suppress renin → false positive ARR. ACEi/ARBs: may cause false negatives (stimulate renin) but are ACCEPTABLE to continue if needed for BP control. Safe alternatives: verapamil, hydralazine, doxazosin (alpha-blocker). Always ensure K⁺ is repleted before testing.
❓ Why does primary aldosteronism cause hypokalemia and metabolic alkalosis?
Aldosterone acts on the principal cells of the collecting duct → activates ENaC → Na⁺ reabsorption creates a negative lumen potential → drives K⁺ and H⁺ secretion. Result: (1) Na⁺ retention → volume expansion → HTN, (2) K⁺ secretion → hypokalemia, (3) H⁺ secretion → metabolic alkalosis. However, only 30-50% of PA patients are hypokalemic at diagnosis -most are normokalemic.
❓ Why does PA cause more cardiovascular damage than essential HTN at the same BP?
Aldosterone has direct mineralocorticoid receptor-mediated effects on the heart, vasculature, and kidneys independent of BP: (1) myocardial fibrosis → LVH and diastolic dysfunction, (2) vascular inflammation and stiffness, (3) glomerular damage → proteinuria, (4) increased AF risk. PA patients have 2-4× higher rates of stroke, MI, and AF compared to BP-matched essential HTN. This is why MRA therapy improves outcomes beyond BP lowering alone, and why the target on medical therapy is a detectable renin rather than simply a normal blood pressure.
Clinical Examples
📋 Case 1, Classic Primary Aldosteronism with Adenoma
Patient: 44M with resistant HTN (BP 162/98 on 3 drugs) and recurrent hypokalemia (K⁺ 2.8 despite 80 mEq KCl daily). PAC 32 ng/dL, PRA 0.2, ARR 160. Saline infusion: PAC 22 (failed suppression). CT: 1.8 cm left adrenal adenoma.
Key findings: Confirmed primary aldosteronism, positive screen (ARR > 30) and positive confirmatory test (saline-suppressed PAC > 10). CT shows unilateral adenoma but CT is wrong 38% of the time.
Management:
Adrenal vein sampling (AVS), mandatory before surgery (CT misidentifies lateralization in 38%)
If AVS lateralizes left → laparoscopic left adrenalectomy (cure rate 50-60% for HTN, ~100% for hypokalemia)
Hold ACEi/ARB 4 weeks before AVS (interfere with renin/aldo ratio)
Post-op: monitor for hyperkalemia (suppressed contralateral zona glomerulosa takes weeks to recover)
Teaching point: Never skip AVS based on CT alone. A 1.8 cm "adenoma" may be a non-functioning incidentaloma, with the real source being bilateral hyperplasia. AVS changes management in 38% of cases.
📋 Case 2, Bilateral Adrenal Hyperplasia
Patient: 56F with resistant HTN (4 drugs), K⁺ 3.2 on supplementation. PAC 24, PRA 0.4, ARR 60. Saline infusion: PAC 14. CT: bilateral adrenal limb thickening. AVS: no lateralization (bilateral aldosterone excess).
Key findings: Bilateral idiopathic hyperaldosteronism (IHA), accounts for ~60% of PA. Surgery not curative (bilateral process). Medical management is definitive therapy.
Management:
Spironolactone 25-50 mg daily, titrate to BP and K⁺ (first-line MRA for PA)
If gynecomastia/breast tenderness → switch to eplerenone 50 mg BID (selective MRA, fewer anti-androgenic effects)
Monitor Cr and K⁺ at 1 week, 4 weeks, then q3-6 months (MRA can cause hyperkalemia especially with CKD)
Teaching point: Bilateral hyperplasia is more common than adenoma. These patients are managed medically for life. Spironolactone is preferred (more potent) but eplerenone avoids anti-androgen side effects in men.
📋 Case 3, Normokalemic Primary Aldosteronism
Patient: 52M with resistant HTN (BP 154/92 on amlodipine, losartan, chlorthalidone). K⁺ consistently 3.8-4.0 (normal). Screened because of resistant HTN. PAC 18 ng/dL, PRA 0.3, ARR 60.
Key findings: Normokalemic PA, up to 50% of PA patients are normokalemic. Hypokalemia is neither sensitive nor specific for PA. Endocrine Society recommends screening all patients with resistant HTN.
Management:
Confirm with saline infusion test or fludrocortisone suppression test
Hold interfering medications before testing: spironolactone (6 weeks), ACEi/ARB (2 weeks), dihydropyridine CCB and alpha-blockers are allowed during testing
If confirmed: CT adrenals → AVS if surgical candidate
Start MRA therapy, many "resistant HTN" patients become controlled once PA is treated
PA may explain 5-10% of all HTN and 20% of resistant HTN
Teaching point: Normal potassium does NOT rule out PA. The classic teaching "hypokalemia = think aldosteronism" misses half of cases. Screen based on resistant HTN, not potassium level.
Sample Presentation
Mr. Kim is a 48-year-old man with resistant hypertension (amlodipine 10, lisinopril 40, HCTZ 25 -BP 158/96) and persistent hypokalemia (K⁺ 3.0 despite supplementation).BMI 28. No secondary HTN features on exam. Labs: PAC 28 ng/dL, PRA 0.3 ng/mL/hr, ARR 93. Confirmatory: saline infusion PAC 18 ng/dL (failed suppression). CT adrenals: 1.4 cm left adrenal adenoma.
Key Points: Confirmed primary aldosteronism -positive ARR, failed saline suppression. CT shows left adenoma, BUT must do adrenal vein sampling before committing to surgery (CT is wrong 38% of the time). Start spironolactone 50 mg while awaiting AVS. Replace K⁺. If AVS lateralizes left → laparoscopic left adrenalectomy.
K⁺ + Cr at 1 week, 4 weeks, then q3-6 months on MRA -hyperkalemia risk (especially with CKD, ACEi/ARB)
BP -target < 130/80. Most patients need additional antihypertensives besides MRA.
ARR is NOT useful for monitoring -it's only a screening test. Follow clinical endpoints (BP, K⁺).
Post-adrenalectomy: Check K⁺ and aldosterone at 1 month. Expect transient hyperkalemia (suppressed contralateral adrenal). Hold MRA. Resume antihypertensives only if BP remains elevated.
Annual cardiovascular risk assessment -PA causes disproportionate end-organ damage. Screen for AF, LVH (echo), proteinuria.
📋 Summary
Summary
Screen Much More Widely Than You Think
The 2025 Endocrine Society guideline recommends screening every hypertensive patient, a change from 2016, which restricted screening to resistant hypertension, hypertension with hypokalemia, an adrenal incidentaloma, early-onset hypertension or a family history of early stroke. Primary aldosteronism is the commonest cause of secondary hypertension and is heavily under-diagnosed.
Hypokalemia Is the Exception, Not the Rule
Most patients with primary aldosteronism are normokalemic. Waiting for a low potassium before screening is the single biggest reason the diagnosis is missed. When it is present, it is a strong clue, often with a metabolic alkalosis.
Screen With the Aldosterone-to-Renin Ratio
A high aldosterone with a suppressed renin is the pattern.Correct the potassium before drawing it, since hypokalemia suppresses aldosterone and produces a false negative. Mineralocorticoid receptor antagonists must be stopped for 4 to 6 weeks; beta blockers falsely raise the ratio and ACE inhibitors, ARBs and diuretics falsely lower it. Verapamil, hydralazine and doxazosin are the interference-free agents to control blood pressure meanwhile.
Confirm Before Localizing
A confirmatory test showing failure to suppress aldosterone with salt loading, by oral sodium loading, saline infusion, fludrocortisone suppression or captopril challenge. Skip confirmation only when the picture is unambiguous: spontaneous hypokalemia with undetectable renin and a clearly raised aldosterone.
Adrenal Vein Sampling Decides the Treatment
CT alone is not enough: non-functioning adenomas are common in older patients and a small aldosterone-producing adenoma can be invisible. Adrenal vein sampling distinguishes a unilateral adenoma, which surgery cures, from bilateral hyperplasia, which it does not.It can be skipped in a patient under 35 with spontaneous hypokalemia and a clear unilateral adenoma on CT.
Unilateral Disease: Operate
Laparoscopic adrenalectomy normalizes the potassium in essentially everyone and cures or greatly improves the blood pressure in most. Check potassium and blood pressure within the first week and stop or halve the MRA and any potassium supplement, because the contralateral gland has been chronically suppressed and transient hyperkalemia is expected.
Bilateral Disease: Block the Receptor
Spironolactone 25 to 100 mg daily is first line.Eplerenone when the anti-androgenic effects (gynecomastia, erectile dysfunction, menstrual irregularity) are not tolerated, at the cost of being less potent and twice-daily. Check potassium and creatinine at 1 week and 4 weeks, then every 3 to 6 months, and remember the hyperkalemia risk multiplies with CKD or a concurrent ACE inhibitor or ARB.
Treat It Even When the Blood Pressure Is Controlled
Aldosterone excess causes cardiac fibrosis, atrial fibrillation, stroke and renal injury out of proportion to the blood pressure, so the target is the hormone, not just the number. On medical therapy, renin should become detectable, which is the marker of adequate receptor blockade; a still-suppressed renin means the dose is too low.
Endocrine Society PA Guidelines 2016 · PATHWAY-2 2015 (spironolactone best add-on for resistant HTN) · PASO 2017 (PA cardiovascular outcomes)
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
Endocrine
Hypothyroidism
Most common endocrine disorder. Hashimoto's thyroiditis is the #1 cause in iodine-sufficient areas. Levothyroxine replacement -simple in concept, nuanced in practice.
TSH -most sensitive test. Elevated in primary hypothyroidism. Normal/low in central hypothyroidism (misleading -always check FT4 if clinical suspicion).
Free T4 -low confirms hypothyroidism. TSH high + FT4 low = primary overt hypothyroidism. TSH high + FT4 normal = subclinical.
TPO antibodies (anti-thyroid peroxidase) -positive in Hashimoto's (~95%). Useful for: (1) confirming etiology, (2) predicting progression from subclinical → overt, (3) informs treatment decisions in subclinical hypothyroidism.
Anti-thyroglobulin antibodies -positive in ~60% of Hashimoto's. Less specific than TPO.
Lipid panel -hypothyroidism causes hyperlipidemia (elevated LDL). May normalize with treatment. Don't start statins until euthyroid.
CK -elevated from hypothyroid myopathy (can be markedly elevated, mimicking rhabdomyolysis)
If central hypothyroidism suspected: check FT4 (not just TSH), pituitary MRI, assess other pituitary axes (ACTH/cortisol, FSH/LH, GH, prolactin). Must rule out adrenal insufficiency before starting T4 (same principle as myxedema coma).
🚨 Management
Management
Levothyroxine (T4): Standard replacement. Full dose: 1.6 mcg/kg/day. Start lower in elderly or cardiac patients: 12.5-25 mcg daily → increase by 12.5-25 mcg q6-8 weeks.
How to take: On empty stomach, 30-60 min before breakfast (or at bedtime, ≥ 3h after last meal). Separate from calcium, iron, PPIs, soy, coffee by ≥ 4 hours (all impair absorption).
Dose adjustments:
Check TSH at 6-8 weeks (TSH has a long half-life -don't recheck sooner).
Target TSH 0.5-2.5 mIU/L for most adults. Elderly (> 70): target 3-6 (higher TSH is protective, over-replacement → AF + osteoporosis).
Pregnancy: target TSH < 2.5 in 1st trimester. Levothyroxine dose typically increases 25-50% during pregnancy. ATA, 2017
⚠ Pregnancy guidance on this page predates the current guideline. The pregnancy and postpartum recommendations below, including the trimester-specific TSH targets, are drawn from the 2017 ATA guideline. That guideline has been replaced by the ATA 2026 Guidelines for Thyroid Disease in Preconception, Pregnancy, and Postpartum, which moves toward a more conservative and individualized approach, including verifying mild abnormalities before treating and pulling back from treating subclinical disease where benefit is not established. Check the 2026 guideline directly before applying these targets to a pregnant patient. Non-pregnancy management on this page is unaffected.
💊 Medications
Medications
Drug
Dose
Route
Notes
Levothyroxine (T4)
1.6 mcg/kg/day (full dose); start 25-50 mcg in elderly
PO
Standard of care. Empty stomach, 30-60 min before breakfast. Separate from Ca, Fe, PPI by 4h. Half-life 7 days → steady state in 6 wk. ATA, 2014
Liothyronine (T3)
5-25 mcg daily (divided BID-TID)
PO
NOT routine. Short half-life → TID dosing. Consider only if persistent symptoms on adequate T4 with normal TSH. Variable absorption.
IV levothyroxine
50-100% of oral dose
IV
For patients who cannot take PO (ICU, post-surgical). 100% bioavailable vs ~70% PO. For myxedema coma: loading dose 200-400 mcg.
🏥 Rounds
Pimp Questions
❓ Why must you wait 6-8 weeks to recheck TSH after a levothyroxine dose change?
Levothyroxine has a half-life of 7 days. It takes approximately 5 half-lives (35 days) to reach steady state. Checking TSH sooner gives a misleading result because the new dose hasn't equilibrated yet. If you increase dose and recheck at 2 weeks, the TSH may still appear elevated → you increase again → overcorrection → iatrogenic hyperthyroidism.
❓ What medications interfere with levothyroxine absorption?
Must separate by ≥ 4 hours: (1) Calcium (supplements and antacids), (2) Iron, (3) PPIs/H2 blockers (need gastric acid for T4 absorption), (4) Soy products, (5) Cholestyramine (binds T4 in gut), (6) Sucralfate, (7) Coffee (reduces absorption by ~30%). Practical advice: take levothyroxine first thing in morning with water only, eat/take other meds ≥ 30-60 min later.
❓ When do you treat subclinical hypothyroidism?
Always treat: TSH > 10, pregnant or planning pregnancy, goiter. Strongly consider treating: TSH 7-10 with positive TPO antibodies (high progression rate to overt hypothyroidism, ~5% per year), symptoms suggestive of hypothyroidism, hyperlipidemia that may improve with treatment. Observe: TSH 4.5-7 without symptoms or risk factors. Elderly > 70: higher TSH may be physiologically normal -treating can cause harm (AF, fractures).
❓ Why should levothyroxine dose be increased in pregnancy?
Pregnancy increases T4 demand by 25-50% due to: (1) increased TBG (estrogen-mediated → more T4 bound, less free), (2) increased plasma volume (dilution), (3) placental deiodinase (degrades T4), (4) fetal thyroid doesn't function until week 12 -fetus depends entirely on maternal T4 for neurodevelopment. Maternal hypothyroidism → lower fetal IQ, neurodevelopmental delay. Increase dose empirically by 2 extra tablets per week when pregnancy confirmed. ATA, 2017
❓ What is the #1 cause of persistently elevated TSH in a patient on levothyroxine?
Non-compliance. Before increasing the dose, always ask: (1) Are you taking it daily? (2) On empty stomach, 30-60 min before eating? (3) Are you taking calcium, iron, or PPIs near the dose? (4) Any new medications? A common pattern: patient takes T4 intermittently, TSH remains elevated → dose is increased → patient takes it consistently for a few days before the lab → TSH normalizes temporarily → cycle repeats.
Clinical Examples
📋 Case 1, New Diagnosis of Hashimoto's Hypothyroidism
Patient: 38F with fatigue, weight gain (12 lb/6 months), constipation, cold intolerance, and menorrhagia. TSH 62 mIU/L, FT4 0.3 ng/dL. TPO Ab 580 IU/mL. No goiter.
Teaching point: In young, healthy patients, start full replacement dose immediately. In elderly or cardiac patients, start low (25-50 mcg) and titrate slowly, rapid correction can precipitate angina or arrhythmia.
📋 Case 2, Hypothyroidism in Pregnancy
Patient: 32F with known Hashimoto's on levothyroxine 75 mcg daily. Newly pregnant (6 weeks). Pre-pregnancy TSH 1.8. Current TSH 4.2, FT4 0.8 ng/dL.
Key findings: TSH above pregnancy target (< 2.5 in first trimester per ATA 2017). Fetal thyroid doesn't function until week 12, fetus depends entirely on maternal T4 for neurodevelopment.
Management:
Increase levothyroxine by ~25-30%: add 2 extra tablets per week (75 mcg × 9/week instead of 7) ATA, 2017
Target TSH < 2.5 mIU/L in first trimester, < 3.0 in second/third trimester
Recheck TSH every 4 weeks through mid-pregnancy, then once at 30 weeks
Maternal hypothyroidism → lower fetal IQ and neurodevelopmental delay
Postpartum: return to pre-pregnancy dose, recheck TSH at 6 weeks postpartum
Teaching point: Pregnancy increases T4 demand by 25-50% due to increased TBG, plasma volume expansion, and placental deiodinase. The "2 extra tablets per week" rule is a practical way to increase dose ~30% immediately.
📋 Case 3, Myxedema Coma
Patient: 72F brought by EMS. Found unresponsive at home. Temp 33.2°C, HR 42, BP 82/50, RR 8. Known hypothyroidism, ran out of levothyroxine 3 months ago. Na 118, glucose 48.
Key findings: Myxedema coma: hypothermia + bradycardia + AMS + hypotension in the setting of severe hypothyroidism. Precipitated by medication non-compliance. Mortality 30-60%.
Management:
IV levothyroxine 200-400 mcg loading dose → 1.6 mcg/kg/day IV (gut absorption unreliable in critical illness)
Stress-dose hydrocortisone 100 mg IV q8h (must rule out concurrent adrenal insufficiency before giving T4, T4 increases cortisol clearance)
Passive rewarming only (active warming → vasodilation → cardiovascular collapse)
D50 for hypoglycemia, hypertonic saline only if Na < 120 with seizures
Teaching point: Always give stress-dose steroids BEFORE or WITH IV levothyroxine in myxedema coma. If undiagnosed adrenal insufficiency coexists (Schmidt syndrome), T4 alone can precipitate adrenal crisis.
Sample Presentation
Mrs. Johnson is a 45-year-old woman with 6 months of fatigue, 10 lb weight gain, constipation, cold intolerance, and hair thinning. PMH: nothing. No medications. Exam: dry skin, periorbital puffiness, bradycardia (HR 56), delayed DTR relaxation. No goiter. Labs: TSH 48 mIU/L (elevated), Free T4 0.4 ng/dL (low), TPO Ab 420 IU/mL (strongly positive).
Key Points: Classic overt primary hypothyroidism from Hashimoto's thyroiditis (positive TPO antibodies). Start levothyroxine ~100 mcg daily (estimated 1.6 × 65 kg). Fasting, 30-60 min before breakfast. Recheck TSH in 6-8 weeks. Target TSH 0.5-2.5. Also check lipids (likely elevated -will improve with treatment).
TSH at 6-8 weeks after any dose change -do NOT recheck sooner (TSH equilibration takes 4-6 weeks). Adjust by 12.5-25 mcg increments.
Annual TSH once stable on appropriate dose
Pregnancy: TSH monthly through first trimester, then q4-6 weeks. Increase dose 25-50% as early as 4-6 weeks gestation. ATA, 2017
Central hypothyroidism: Monitor Free T4 (NOT TSH -TSH is unreliable when the pituitary is the problem). Target FT4 in upper half of reference range.
Elderly (> 70): Target TSH 3-6. Do NOT over-replace -subclinical hyperthyroidism from excess T4 → AF, osteoporosis, fractures.
Drug interactions: Reassess dose when starting/stopping calcium, iron, PPIs, estrogen (increases TBG → need more T4), phenytoin/carbamazepine (increase T4 metabolism).
Lipid panel -recheck 3-6 months after achieving euthyroidism (hyperlipidemia often normalizes).
📋 Summary
Summary
Diagnose on TSH First
A raised TSH with a low free T4 is primary hypothyroidism.Hashimoto thyroiditis is the commonest cause in iodine-sufficient regions, confirmed by TPO antibodies. A low or inappropriately normal TSH with a low free T4 means central hypothyroidism, which needs pituitary imaging and assessment of the other axes.
Check Cortisol Before Thyroid Hormone in Suspected Central Disease
Treating hypothyroidism in an unrecognized adrenal insufficiency precipitates adrenal crisis, because thyroid hormone increases cortisol clearance and metabolic demand. In panhypopituitarism, give the glucocorticoid first.
Dose and Give It Properly
Levothyroxine 1.6 mcg/kg/day as a full replacement dose.Start at 25 to 50 mcg in the elderly and in coronary disease, since a full dose can precipitate angina or arrhythmia. Take it on an empty stomach, 30 to 60 min before breakfast, and separate it by 4 hours from calcium, iron, proton pump inhibitors and bile acid sequestrants, which block absorption. Poor absorption from mistimed dosing is the commonest reason a TSH will not come down.
Recheck at 6 Weeks, Not Sooner
Levothyroxine has a 7-day half-life, so a steady state takes about 6 weeks.Checking earlier gives a number that has not equilibrated and leads to unnecessary dose changes.Titrate by 12.5 to 25 mcg and recheck after another 6 weeks.
T3 Is Not Routine
Combination T4 and T3 has not shown consistent benefit in trials, and liothyronine has a short half-life needing TID dosing with supraphysiologic peaks. Consider it only for persistent symptoms with a normalized TSH, after excluding the other causes of fatigue, and never as first-line therapy. Desiccated thyroid extract has an unphysiologic T4:T3 ratio and is not recommended.
Treat Subclinical Disease Selectively
Raised TSH with a normal free T4.Treat when TSH is above 10, when TPO antibodies are positive with symptoms, in pregnancy or when trying to conceive, and in goiter.Observe when TSH is 4.5 to 10 in an asymptomatic older adult, where a mildly raised TSH may be an age-appropriate finding and treating it adds no benefit.
Pregnancy Changes Everything
Requirements rise by roughly 30% and the increase is needed early, so instruct a known hypothyroid patient to increase the dose as soon as pregnancy is confirmed (commonly by two extra tablets a week) and check TSH immediately. Trimester-specific targets are lower than the usual range, and untreated maternal hypothyroidism impairs fetal neurodevelopment, which is why this is one of the few settings where treatment is urgent.
Know Why the TSH Will Not Normalize
Non-adherence is the commonest reason, followed by mistimed dosing with food or interacting drugs, malabsorption (celiac disease, atrophic gastritis, bariatric surgery), and drug interference from amiodarone, lithium, checkpoint inhibitors, estrogen and rifampin. A suppressed TSH means over-replacement, which is not benign: it causes atrial fibrillation and bone loss, especially in the elderly. Do not chase the TSH in acute illness: euthyroid sick syndrome produces abnormal results that resolve on recovery, so retest after the illness rather than treating the number.
RoundsRx Infographic Series · #188 · Renal & Metabolic · PDF 145 KB
Text version
One-Pager
Hypothyroidism
Simple drug, nuanced dosing
Levothyroxine Rules
1.6 mcg/kg/day. Empty stomach, 30-60 min before food. Separate Ca/Fe/PPI by 4h. Start low in elderly/cardiac (25 mcg). Recheck TSH at 6-8 weeks. Target 0.5-2.5.
Subclinical Decision
TSH > 10 → treat. TSH 7-10 + TPO+ → treat. Pregnant → treat (target < 2.5). Elderly → often observe (higher TSH may be normal).
Trials
ATA Hypothyroidism Guidelines 2014 · ATA Thyroid in Pregnancy 2017
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
Heme/Onc
Multiple Myeloma
Malignant plasma cell neoplasm producing monoclonal immunoglobulin. CRAB criteria define end-organ damage. Intern role: recognize, manage complications, support through chemo.
🔍 Overview
Overview
Multiple myeloma (MM) is a clonal plasma cell neoplasm in the bone marrow producing a monoclonal immunoglobulin (M-protein). Median age at diagnosis: 69 years, more common in African Americans (2×). The disease spectrum: MGUS → smoldering myeloma → active myeloma. Active myeloma requires CRAB criteria (end-organ damage): C alcium elevated (> 11) · R enal insufficiency (Cr > 2) · A nemia (Hgb < 10) · B one lesions (lytic on skeletal survey or PET/CT). SLiM criteria added in 2014: S ixty percent bone marrow plasma cells · Li ght chain ratio ≥ 100 · M RI with > 1 focal lesion ≥ 5mm -these define myeloma even without CRAB. IMWG, 2014
🧪 Workup
Workup
SPEP + UPEP with immunofixation -detects M-protein. SPEP identifies the spike; immunofixation types it (IgG most common, then IgA). UPEP detects Bence Jones proteinuria (free light chains).
Serum free light chains (sFLC) -kappa:lambda ratio. Abnormal ratio with elevated involved chain supports monoclonal process. Essential for light-chain-only myeloma (15%).
CBC -anemia (normocytic, rouleaux on smear), may have leukopenia/thrombocytopenia with advanced marrow infiltration
Skeletal survey (whole-body low-dose CT or PET/CT) -lytic lesions (punched-out). Do NOT use DEXA or conventional XR for screening. PET/CT preferred (more sensitive).
Anti-CD38 mAb. Infusion reactions (pre-medicate). Interferes with blood bank crossmatch (anti-CD38 on reagent RBCs). MAIA, 2019
Dexamethasone
40 mg weekly (20 mg if > 75y)
PO
Backbone of all myeloma regimens. Hyperglycemia, insomnia, mood changes, infection risk.
Zoledronic acid
4 mg IV over 15 min q4w
IV
Bone-modifying agent. Reduces SREs. Dental exam before starting (ONJ risk). Dose-adjust for CrCl. MRC Myeloma IX, 2012
Carfilzomib
20-56 mg/m² IV
IV
2nd-gen proteasome inhibitor for relapsed MM. Cardiac toxicity (HF, HTN) -check echo baseline. Less neuropathy than bortezomib.
🏥 Rounds
Pimp Questions
❓ What are the CRAB criteria?
C alcium > 11 mg/dL · R enal insufficiency (Cr > 2 or CrCl < 40) · A nemia (Hgb < 10 or 2 g below normal) · B one disease (lytic lesions, pathologic fractures, osteoporosis with compression fracture). Any one of these in the setting of a clonal plasma cell disorder = active myeloma requiring treatment. IMWG, 2014
❓ Why does daratumumab interfere with blood bank crossmatching?
Daratumumab (anti-CD38) binds to CD38 expressed on reagent red blood cells used in the blood bank, causing a panreactive indirect Coombs test. This makes antibody identification impossible. Solutions: (1) notify blood bank before starting daratumumab, (2) use DTT-treated RBCs (denatures CD38), (3) phenotype/genotype patient RBCs before first dose. Critical for transfusion safety.
❓ What is the mechanism of myeloma kidney (cast nephropathy)?
Free light chains (especially lambda) are filtered by glomeruli and form obstructive casts in distal tubules by binding with Tamm-Horsfall protein. This causes tubular obstruction, inflammation, and fibrosis → AKI/CKD. Aggravated by: dehydration, NSAIDs, IV contrast, loop diuretics (increase Tamm-Horsfall), hypercalcemia. Treatment: aggressive hydration, treat myeloma (reduce light chain production), consider plasmapheresis if very high FLC.
❓ What is the difference between MGUS, smoldering myeloma, and active myeloma?
MGUS: M-protein < 3 g/dL + < 10% marrow plasma cells + no CRAB. Risk of progression: ~1%/year. No treatment -observe. Smoldering myeloma: M-protein ≥ 3 OR 10-59% marrow plasma cells + no CRAB/SLiM. Higher risk (~10%/year first 5 years). Observation vs early treatment (emerging data). Active myeloma: CRAB or SLiM criteria met → treat. IMWG, 2014
❓ Why do myeloma patients need VZV prophylaxis on bortezomib?
Bortezomib (proteasome inhibitor) causes profound T-cell immunosuppression by inhibiting NF-κB signaling in T lymphocytes. This predisposes to VZV reactivation (shingles) in up to 13% without prophylaxis. Acyclovir 400 mg BID (or valacyclovir 500 mg daily) reduces risk to < 2%. Continue throughout bortezomib therapy + 3 months after.
❓ What high-risk cytogenetic features change myeloma prognosis?
High-risk FISH: del(17p) (loss of TP53 -worst prognosis), t(4;14) (FGFR3/MMSET), t(14;16) (MAF), t(14;20), gain(1q21), del(1p). Standard risk: t(11;14) (cyclin D1), t(6;14), hyperdiploidy. High-risk patients have median OS ~3-4 years vs > 7 years for standard risk. Treatment intensification (quadruplet induction, tandem ASCT) for high-risk.
Clinical Examples
📋 Case 1, Newly Diagnosed Myeloma with Renal Failure
Patient: 68M with fatigue, bone pain, and foamy urine × 2 months. Hgb 8.2, Ca 13.4, Cr 3.8 (baseline 1.0), total protein 10.8. SPEP: IgG kappa M-spike 5.1 g/dL. sFLC kappa 1240, ratio 98. BMBx: 72% clonal plasma cells.
Key findings: Active myeloma: CRAB criteria met (Ca 13.4, Renal Cr 3.8, Anemia Hgb 8.2) + SLiM (72% plasma cells). Myeloma kidney (cast nephropathy), light chains forming obstructive casts in distal tubules.
Management:
Aggressive IVF (NS 200 mL/hr), dehydration worsens cast formation. Avoid IV contrast and NSAIDs
Zoledronic acid 4 mg IV for hypercalcemia (hold if Cr > 4.5, use denosumab instead)
Bortezomib is preferred in renal failure (not renally cleared, rapid light chain reduction)
Transplant eligibility assessment, age alone does not exclude; assess fitness
Teaching point: Myeloma kidney is driven by free light chains, not M-protein. Rapid light chain reduction with bortezomib-based therapy is key to renal recovery. ~50% of patients with myeloma kidney recover renal function if treated promptly.
📋 Case 2, Transplant-Eligible Myeloma
Patient: 58F with back pain and pathologic L2 compression fracture. Hgb 9.8, Ca 10.8, Cr 1.1. SPEP: IgA lambda M-spike 3.2 g/dL. BMBx: 45% plasma cells. PET/CT: multiple lytic lesions. FISH: standard risk [t(11;14)].
Key findings: Standard-risk myeloma. Fit, age < 65, transplant-eligible. Bone disease with pathologic fracture. Standard risk t(11;14) has favorable prognosis.
ASCT deepens response and extends PFS by ~12 months IFM 2009, 2017
Lenalidomide maintenance post-ASCT until progression (doubles PFS)
Zoledronic acid monthly × 2 years for bone protection
Radiation to L2 fracture for pain + kyphoplasty consult for structural support
Teaching point: Lenalidomide maintenance after ASCT is standard of care, it roughly doubles PFS. For t(11;14) specifically, venetoclax-based combinations are emerging as highly effective (BCL-2 overexpression).
📋 Case 3, Smoldering Myeloma: To Treat or Not?
Patient: 62M found to have M-spike 2.8 g/dL on routine labs. Asymptomatic. Hgb 13.2, Ca 9.8, Cr 0.9. sFLC ratio 18. BMBx: 22% plasma cells. No lytic lesions on PET/CT. No SLiM criteria.
Key findings: Smoldering myeloma: ≥ 10% plasma cells + M-protein ≥ 3 g/dL, but NO CRAB or SLiM criteria. Risk of progression ~10%/year for first 5 years. High-risk features: sFLC ratio > 20, M-spike > 2, BMBx > 20%.
Management:
Standard approach: observation with monitoring q3-6 months (SPEP, CBC, Ca, Cr, sFLC)
Clinical trial enrollment for high-risk smoldering (early intervention trials ongoing)
Annual skeletal imaging (low-dose CT or PET/CT) to detect new bone lesions
Teaching point: Treating smoldering myeloma is NOT standard of care outside clinical trials. The CRAB and SLiM criteria define the line between observation and treatment. However, high-risk smoldering patients may benefit from early intervention, encourage trial enrollment.
Sample Presentation
Mr. Wallace is a 71-year-old man presenting with progressive low back pain × 3 months, fatigue, and 15 lb weight loss. Found to have: Hgb 8.4, Ca 12.8, Cr 2.6, total protein 11.2. SPEP: IgG kappa M-spike 4.2 g/dL. sFLC: kappa 890, lambda 12, ratio 74. Skeletal survey: multiple lytic lesions in spine, pelvis, skull. BMBx: 65% clonal plasma cells, FISH: standard risk.
Key Points: Active myeloma with full CRAB: Ca 12.8, Cr 2.6, Anemia (Hgb 8.4), Bone lesions. Also meets SLiM (60% plasma cells). ISS Stage III (β2M likely elevated with that Cr). Immediate: IV hydration + zoledronic acid for hypercalcemia, transfuse for Hgb < 7, renal protection. Start VRd induction. Transplant-ineligible at 71 → consider DRd.
CBC + BMP before each cycle -cytopenias, renal function
Ca²⁺ -trending (hypercalcemia is a myeloma emergency)
Peripheral neuropathy assessment -on bortezomib. Grade ≥ 2 → dose-reduce or switch to carfilzomib.
Echo -baseline + periodic on carfilzomib (cardiotoxicity)
Dental exam q6 months on bisphosphonates (ONJ monitoring)
Cr + urine protein -myeloma kidney monitoring. Improving Cr on treatment = good prognostic sign.
Quantitative Ig -immune paresis monitoring. IVIG if recurrent serious infections.
📋 Summary
Summary
CRAB Defines the Disease
Calcium elevated, Renal insufficiency, Anemia, Bone lesions. These are what separate myeloma from smoldering myeloma and MGUS, which are the same clone without end-organ damage. Add the myeloma-defining events: clonal plasma cells 60% or more, a serum free light chain ratio of 100 or more, or more than one focal lesion on MRI, each of which mandates treatment before CRAB features appear.
Work It Up in Three Layers
Serum and urine protein electrophoresis with immunofixation, plus serum free light chains.Bone marrow biopsy with cytogenetics and FISH, which drive risk stratification. Whole-body low-dose CT, PET-CT or whole-body MRI for the bones.Do not order a skeletal survey: plain films need about 30% bone loss before a lesion is visible and they miss disease that modern imaging finds.
The Lesions Are Lytic and Cold
Bone scan is falsely negative in myeloma, because it detects osteoblastic activity and myeloma is purely osteolytic with suppressed osteoblasts. Ordering a bone scan for myeloma bone pain is a classic error and delays the diagnosis.
Protect the Kidney Early
Cast nephropathy from free light chains is the main renal lesion, worsened by dehydration, NSAIDs, contrast, hypercalcemia and infection. Aggressive hydration, avoid nephrotoxins, treat the hypercalcemia, and start anti-myeloma therapy quickly, since lowering the light chain burden is what actually rescues renal function. Bortezomib-based regimens are preferred in renal impairment because they do not need renal dose adjustment.
Standard Therapy Is a Triplet or Quadruplet
Proteasome inhibitor plus immunomodulatory drug plus dexamethasone, increasingly with daratumumab added. Autologous stem cell transplant for eligible patients, so avoid prolonged lenalidomide before stem cell collection, which impairs the harvest. Then maintenance, typically lenalidomide.
Know the Toxicity of Each Component
Bortezomib: peripheral neuropathy is dose-limiting, and it reactivates varicella zoster, so give acyclovir prophylaxis.Lenalidomide: VTE risk requires thromboprophylaxis, it is teratogenic, and it needs renal dose reduction.Daratumumab: infusion reactions requiring premedication, and it interferes with blood typing, so type and screen before the first dose or later crossmatching becomes difficult. Dexamethasone: hyperglycemia, insomnia, mood change and infection risk.
Manage the Bones and the Calcium
Bisphosphonates or denosumab for all patients with bone disease, which reduce skeletal-related events. Watch for osteonecrosis of the jaw, so arrange a dental review before starting. Denosumab where renal function precludes zoledronic acid.Radiation for painful focal lesions and for cord compression, and orthopedic input for an impending pathological fracture of a long bone.
Anticipate Infection and the Emergencies
Infection is the leading cause of death, driven by functional hypogammaglobulinemia plus treatment-related immunosuppression: vaccinate, give acyclovir with a proteasome inhibitor, and consider PJP prophylaxis and IVIG for recurrent infection. Recognize hypercalcemia, spinal cord compression, hyperviscosity and renal failure as the emergencies, each of which can be the presenting event.
Malignant proliferation of immature myeloid (AML) or lymphoid (ALL) blasts. The intern manages complications: TLS, DIC, leukostasis, infections, and transfusion support.
🔍 Overview
Overview
Acute leukemia = rapid clonal expansion of immature hematopoietic cells (blasts) in the bone marrow, spilling into blood. AML (acute myeloid): median age 68, most common adult acute leukemia. ALL (acute lymphoblastic): bimodal -peak in children 2-5y + second peak > 60y. Diagnosis: ≥ 20% blasts in marrow or blood (WHO). Exception: AML with recurrent genetic abnormalities (e.g. t(8;21), inv(16)) can be diagnosed at any blast %. APL (acute promyelocytic leukemia, M3): medical emergency -presents with severe DIC. Treat with ATRA immediately on suspicion, before confirmation. The intern's role: you will not choose chemo regimens -you WILL manage TLS prevention, febrile neutropenia, DIC, transfusion, electrolytes, and pain.
🧪 Workup
Workup
CBC with differential + peripheral smear -blasts (≥ 20%), may see Auer rods (AML, especially APL). WBC can be markedly elevated (leukostasis risk if > 100K) or low (aleukemic leukemia).
Bone marrow biopsy + aspirate -definitive. Send: morphology, flow cytometry (lineage: myeloid vs lymphoid), cytogenetics (karyotype), FISH (specific translocations), molecular testing (FLT3, NPM1, IDH1/2, TP53 for AML; BCR-ABL for ALL).
DIC: Aggressive blood product support (cryoprecipitate for fibrinogen < 100-150, platelets for < 50K with bleeding). Treat the leukemia (definitive DIC treatment).
Febrile neutropenia: Cefepime or meropenem within 1 hour. See neutropenic fever protocol.
Transfusion: pRBC for Hgb < 7-8. Platelets for < 10K (prophylactic) or < 50K with bleeding. Irradiated + leukoreduced products.
Backbone of AML "7+3." High-dose for consolidation. Cerebellar toxicity at high dose (check cerebellar function daily).
Venetoclax
400 mg daily (after ramp-up)
PO
BCL-2 inhibitor. With azacitidine for unfit AML. High TLS risk -ramp-up dosing + rasburicase. VIALE-A, 2020
Midostaurin
50 mg BID days 8-21
PO
FLT3 inhibitor added to 7+3 for FLT3-mutated AML. RATIFY, 2017
Hydroxyurea
50-100 mg/kg/day
PO
Cytoreduction for leukostasis (WBC > 100K). Bridge until definitive chemo. Also for SCD maintenance.
🏥 Rounds
Pimp Questions
❓ Why must you start ATRA immediately when APL is suspected?
APL (M3 AML) presents with severe DIC that is rapidly fatal without treatment. ATRA differentiates the malignant promyelocytes, which resolves the DIC within days. Mortality from APL-related hemorrhage is highest in the first 48-72 hours. Waiting for FISH confirmation of t(15;17) PML-RARA can take 2-5 days -too long. Start ATRA on clinical/morphologic suspicion (Auer rods + DIC + promyelocytic morphology). If wrong, ATRA has minimal toxicity.
❓ What is differentiation syndrome and how do you manage it?
Differentiation syndrome (formerly "ATRA syndrome") occurs when ATRA/ATO causes rapid maturation of leukemic promyelocytes → release of cytokines → capillary leak. Features: fever, dyspnea, weight gain, pulmonary infiltrates, pleural/pericardial effusions, hypotension. Can be fatal. Treatment: dexamethasone 10 mg IV BID + continue ATRA (unless life-threatening). Hold ATRA only if severe. Occurs in ~25% of APL patients, typically within first 1-2 weeks.
❓ What is leukostasis and at what WBC does it occur?
Leukostasis = symptomatic hyperviscosity from WBC plugging microvasculature. Typically when WBC > 100K (lower threshold for AML blasts -larger and stickier than ALL blasts). Symptoms: dyspnea, hypoxia, confusion, visual changes, headache. Treatment: emergent leukapheresis + hydroxyurea. Do NOT transfuse pRBCs before reducing WBC (increases viscosity). AML leukostasis is more dangerous than ALL at the same WBC.
❓ What molecular markers are most important in AML and why?
FLT3-ITD: present in ~30% AML. Worse prognosis. Add midostaurin to 7+3 RATIFY, 2017. NPM1: favorable if FLT3-negative -may not need transplant in CR1. IDH1/IDH2: targetable with ivosidenib/enasidenib. TP53: very poor prognosis -poor response to standard chemo. t(8;21), inv(16): core-binding factor AML -favorable, respond well to high-dose cytarabine consolidation.
❓ Why are blood products in leukemia patients irradiated and leukoreduced?
Irradiated: prevents transfusion-associated graft-versus-host disease (TA-GVHD) -donor lymphocytes in the blood product attack the immunocompromised recipient's tissues. TA-GVHD is > 90% fatal. Irradiation inactivates donor lymphocytes. Leukoreduced: removes WBCs → prevents febrile non-hemolytic transfusion reactions, CMV transmission, and HLA alloimmunization (important for future transplant candidates).
Clinical Examples
📋 Case 1, APL (Acute Promyelocytic Leukemia) with DIC
Patient: 32F with 10 days of fatigue, bruising, and epistaxis. WBC 3.2K with 45% blasts, Hgb 7.1, platelets 18K. PT 19, fibrinogen 82. Smear: bilobed blasts with heavy granulation and Auer rods.
Key findings: APL [t(15;17) PML-RARA] with DIC, the hematologic emergency. APL is the most curable leukemia but the most dangerous at presentation due to DIC-related hemorrhage.
Management:
Start ATRA (all-trans retinoic acid) 45 mg/m²/day IMMEDIATELY, do not wait for FISH confirmation
Aggressive product support: cryoprecipitate to keep fibrinogen > 150 mg/dL, platelets > 30-50K (higher thresholds for APL)
Watch for differentiation syndrome (fever, dyspnea, weight gain, pulmonary infiltrates), treat with dexamethasone 10 mg IV BID
FISH for PML-RARA t(15;17) to confirm
Teaching point: APL is a clinical diagnosis, start ATRA on morphologic suspicion alone (Auer rods + DIC). Waiting for FISH costs lives. ATO+ATRA cures > 95% of low-risk APL without traditional chemotherapy.
📋 Case 2, AML with Leukostasis
Patient: 65M with 1 week of confusion and dyspnea. WBC 142K with 88% blasts, Hgb 8.2, platelets 34K. SpO₂ 88% on room air. CXR: bilateral interstitial infiltrates. CT head: no bleed.
Key findings: Leukostasis, WBC > 100K with symptomatic microvascular plugging (pulmonary: hypoxia; CNS: confusion). AML blasts are large and sticky, leukostasis occurs at lower WBC than ALL.
Management:
Emergent leukapheresis to rapidly reduce WBC (temporizing, effect lasts hours)
Hydroxyurea 50-100 mg/kg/day to cytoreduction (start immediately, even before pheresis)
DO NOT transfuse pRBCs until WBC is reduced (increases viscosity → worsens leukostasis)
TLS prophylaxis: aggressive IVF + rasburicase (tumor lysis is imminent with cytoreduction)
Expedite bone marrow biopsy, cytogenetics, and molecular markers for definitive therapy
Teaching point: Leukostasis is a clinical diagnosis, there is no specific WBC threshold. Do not wait for confirmatory tests. The immediate goal is cytoreduction, not diagnosis. Avoid pRBC transfusion until WBC is lowered.
📋 Case 3, Newly Diagnosed ALL in Young Adult
Patient: 22M with 3 weeks of fatigue, bone pain, and fever. WBC 48K with 72% lymphoblasts, Hgb 9.4, platelets 28K. Mediastinal mass on CXR. Flow cytometry: TdT+, CD10+, CD19+, CD22+.
Key findings: B-cell ALL. Young adult with mediastinal mass (T-cell features possible). Must check for Philadelphia chromosome [t(9;22) BCR-ABL], present in 25% of adult ALL and changes therapy entirely.
Management:
FISH for BCR-ABL (Philadelphia chromosome), if positive, add dasatinib or ponatinib to chemotherapy
Pediatric-inspired regimen (hyper-CVAD or DFCI protocol), AYA patients (< 40) have better outcomes with pediatric protocols CALGB 10403, 2019
LP with intrathecal methotrexate (CNS prophylaxis, ALL has high CNS tropism)
TLS prophylaxis: IVF + allopurinol (or rasburicase if high risk)
HLA typing for siblings early, allogeneic transplant may be indicated in CR1 for high-risk features
Teaching point: Always check for Philadelphia chromosome in adult ALL, it's present in 25% of cases and is the single most important prognostic and therapeutic marker. Ph+ ALL gets TKI + chemo, not chemo alone.
Sample Presentation
Ms. Chen is a 58-year-old woman presenting with 2 weeks of fatigue, easy bruising, and gum bleeding. Exam: pallor, petechiae, gingival hyperplasia. Labs: WBC 68K with 78% blasts, Hgb 6.8, platelets 12K, LDH 1200, uric acid 9.2. Smear: large blasts with Auer rods. PT 18, fibrinogen 95.
Key Points: AML with Auer rods + DIC (fibrinogen 95, prolonged PT) → high suspicion for APL. Start ATRA immediately. Aggressive product support: cryoprecipitate for fibrinogen > 150 (higher target in APL), platelets for > 30-50K (APL bleeding threshold). TLS prevention: IVF + rasburicase (uric acid 9.2 + high WBC). Confirm with FISH for PML-RARA t(15;17).
CBC daily during induction -track nadir (typically days 10-21 for AML). Expect 2-4 weeks of pancytopenia.
TLS labs q6-8h -K⁺, PO₄, Ca²⁺, uric acid, Cr, LDH during first 72h of treatment
Rapid clonal expansion of immature myeloid (AML) or lymphoid (ALL) blasts. The oncologist chooses the chemotherapy; the ward team manages the complications that kill first: tumor lysis, DIC, leukostasis, neutropenic infection and transfusion support.
Confirm and Type It Fast
Peripheral smear, then bone marrow aspirate and biopsy with flow cytometry, cytogenetics and molecular testing.Blasts above 20% makes the diagnosis.Auer rods mean myeloid.Cytogenetics decide both prognosis and treatment, so do not start therapy that would make the marrow uninterpretable before it is sampled.
APL Is the One You Diagnose Clinically
Suspect acute promyelocytic leukemia and start ATRA 45 mg/m²/day immediately, before the cytogenetics confirm it.APL kills through catastrophic DIC and intracranial hemorrhage in the first days, and ATRA reverses the coagulopathy. Support aggressively: keep fibrinogen above 150 and platelets above 50,000. With ATRA plus arsenic trioxide the cure rate exceeds 90%, so the early death is the only thing standing between the patient and a cure.
Watch for Differentiation Syndrome
ATRA and arsenic cause fever, dyspnea, hypoxemia, pulmonary infiltrates, weight gain, hypotension and renal dysfunction, usually in the first 2 weeks.Treat with dexamethasone 10 mg IV BID at the first suspicion and do not wait for confirmation, because it progresses to respiratory failure. Hold the differentiating agent in severe cases.
Tumor Lysis Prophylaxis From the Start
Aggressive IV fluids plus allopurinol; rasburicase for high risk or an already high uric acid (contraindicated in G6PD deficiency, where it causes hemolysis). Monitor potassium, phosphate, calcium, uric acid and creatinine every 6 to 8 h.Do not give calcium for asymptomatic hypocalcemia, since calcium-phosphate precipitation worsens the kidney injury. Venetoclax carries a particularly high risk, which is why it is ramped up rather than started at full dose.
Leukostasis Is a Different Emergency
WBC above 100,000 in AML with dyspnea, hypoxemia, confusion or visual change.Cytoreduce with hydroxyurea 50 to 100 mg/kg/day and consider leukapheresis, and start definitive therapy urgently. Do not transfuse red cells before cytoreduction: raising the hematocrit raises viscosity and can precipitate stroke or infarction. Platelets are safe and should be given.
Neutropenic Fever Is a One-Hour Problem
Cultures then broad-spectrum antipseudomonal antibiotics within 1 hour, before imaging and before the source is known.A single temperature of 38.3°C, or 38.0°C sustained for an hour, with an ANC below 500 counts.Add antifungal cover for persistent fever beyond 4 to 7 days, and remember these patients may have no localizing signs because they cannot mount inflammation.
Transfusion and Supportive Details That Matter
Use irradiated and leukoreduced products to prevent transfusion-associated GVHD and CMV transmission in a potential transplant candidate. Platelets below 10,000, or below 50,000 with bleeding or a procedure.All ALL patients need CNS prophylaxis with intrathecal chemotherapy, because the CNS is a sanctuary site systemic therapy does not reach. Add PJP prophylaxis and antiviral prophylaxis, and discuss fertility preservation before induction, not after.
Warfarin vs DOACs vs heparin: choosing, dosing, monitoring, bridging, and reversal. The most commonly consulted hematology topic on wards.
🔍 Overview
Overview
Anticoagulation management is one of the most common daily tasks on inpatient medicine. Key decisions: (1) Which agent? Heparin (UFH for acute, can titrate, dialyzable) vs LMWH (predictable, SQ, no monitoring) vs warfarin (outpatient, INR monitoring, cheap) vs DOAC (outpatient, no monitoring, fewer interactions, not all indications). (2) When to bridge? Only high-risk patients (mechanical valve, recent VTE < 3 months, prior thrombosis on interruption). (3) How to reverse? Warfarin: vitamin K ± 4-factor PCC. DOACs: idarucizumab (dabigatran), andexanet alfa (Xa inhibitors), or 4F-PCC. Heparin: protamine. Key intern skill: recognizing bleeding vs thrombotic risk and adjusting therapy accordingly.
Warfarin-only indications (DOACs are contraindicated): (1) Mechanical heart valves - RE-ALIGN, 2013 showed excess valve thrombosis with dabigatran. (2) Triple-positive antiphospholipid syndrome - TRAPS, 2018 showed excess arterial events with rivaroxaban. (3) Moderate-severe (rheumatic) mitral stenosis - INVICTUS, 2022 showed warfarin superior to rivaroxaban with lower mortality. For ALL other indications (nonvalvular AF, VTE), DOACs are preferred over warfarin. Key distinction: the warfarin mandate is for rheumatic moderate-severe MS specifically, not any severe MS. The cause matters, not just the severity. Non-rheumatic severe MS (e.g., calcific MS from mitral annular calcification in the elderly) is not a DOAC contraindication, because it lacks the thrombogenic rheumatic left-atrial substrate INVICTUS studied; a DOAC is reasonable there (data are limited, so individualize if the LA is markedly enlarged/stagnant).
When to choose each anticoagulant: UFH = acute (titratable, reversible, dialyzable). LMWH = predictable SQ dosing, cancer VTE. Warfarin = mechanical valve, APS, severe CKD (CrCl < 15), cost. DOAC = everything else (AF, VTE) - fewer interactions, no monitoring, rapid onset. Fondaparinux = HIT with VTE (no heparin cross-reactivity).
Warfarin monitoring: INR (target 2-3 for most indications; 2.5-3.5 for mechanical mitral valve). Check INR daily inpatient until stable, then q1-4 weeks outpatient.
Heparin monitoring: aPTT q6h after initiation or dose change (anti-Xa levels if aPTT unreliable -lupus anticoagulant, elevated baseline). Target aPTT per institutional protocol (usually 1.5-2.5× control).
DOACs: No routine monitoring. Check Cr + CrCl (dose-adjust apixaban/rivaroxaban at CrCl 15-30; dabigatran CI if CrCl < 30). Drug-specific anti-Xa (rivaroxaban, apixaban) or dTT (dabigatran) for special situations (overdose, pre-surgery, bleeding).
VTE treatment: DOAC preferred (rivaroxaban or apixaban). Duration: provoked DVT = 3 months; unprovoked = extended (reassess annually). Cancer-associated VTE: LMWH or DOAC (edoxaban, rivaroxaban) [HOKUSAI VTE Cancer, 2018; SELECT-D, 2018]. Exception: GI/GU cancer with high bleed risk → LMWH preferred.
AF anticoagulation: DOAC preferred over warfarin for nonvalvular AF [RE-LY, ROCKET AF, ARISTOTLE, ENGAGE AF-TIMI 48]. Exception: moderate-severe mitral stenosis or mechanical valve → warfarin only.
Two kinds of bridging. "Bridge" means using a fast parenteral anticoagulant (UFH/LMWH) to cover any window when warfarin is sub-therapeutic -which happens in two settings. (1) Initiation bridging: starting warfarin in someone with an acute clot (new DVT/PE, LV thrombus, new mechanical valve). Overlap heparin/LMWH until INR ≥ 2 for 24h (minimum 5-day overlap), because warfarin takes 5-7 days to work AND is transiently procoagulant in the first few days (protein C and S fall before factors II, IX, X -the same mechanism behind warfarin skin necrosis). (2) Periprocedural bridging: interrupting warfarin for surgery and covering the gap -detailed below. DOACs need neither, since they are immediately therapeutic; the only exception is the 5-day heparin lead-in for edoxaban and dabigatran in VTE.
Perioperative bridging:
Most patients: do NOT bridge.BRIDGE, 2015 -bridging with LMWH in AF patients on warfarin increased bleeding without reducing thrombosis.
Bridge ONLY high thrombotic risk (roughly > 10%/yr off anticoagulation):
Mechanical valve: ANY mitral mechanical valve; any older caged-ball (Starr-Edwards) or tilting-disc (Björk-Shiley) valve; any mechanical valve + stroke/TIA within 6 months. Why: highest stasis and thrombogenicity, and a periprocedural clot here means valve thrombosis or disabling stroke. Exception: an isolated bileaflet aortic valve (St. Jude, On-X, CarboMedics) with no other risk factors is the one mechanical valve that does NOT need bridging (low-thrombogenicity, high-flow position; see box below).
AFib: CHA₂DS₂-VASc ≥ 7, stroke/TIA within 3 months, or rheumatic (valvular) AF. Why: recent cardioembolism predicts early recurrence, and rheumatic mitral stenosis carries the highest AF stroke rate.
VTE: VTE within the last 3 months, or severe thrombophilia (protein C/S deficiency, antiphospholipid syndrome, homozygous factor V Leiden). Why: clot is still organizing and recurrence risk is steepest in the first 3 months.
Stop warfarin 5 days before. Stop DOAC 2-3 days before (longer if CKD). Resume 24-72h post-procedure depending on bleeding risk.
The only mechanical valve you DON'T bridge: an isolated bileaflet aortic valve (St. Jude, On-X, CarboMedics) with no other risk factors. Why: modern bileaflet design is the least thrombogenic mechanical valve, and the high-flow, low-stasis aortic position drops the off-anticoagulation thromboembolic risk below ~5%/yr (low-risk tier), so the bleeding cost of bridging outweighs the small thrombotic benefit during a brief warfarin hold. It jumps back into bridge-worthy territory with ANY of: AFib, prior stroke/TIA, LV dysfunction, HTN, diabetes, age > 75, or more than one mechanical valve. Every mitral mechanical valve, and every older caged-ball (Starr-Edwards) or tilting-disc (Björk-Shiley) valve, is always bridged.
DOAC perioperative management is simpler than warfarin: No bridging needed. Simply hold the DOAC 24-48h pre-procedure (48-72h if CrCl < 50 or high-bleed-risk surgery). Resume 24-48h post-procedure. The PAUSE trial validated this approach with low rates of both thromboembolism (0.16%) and major bleeding (1.35%). PAUSE, 2019
Reversal:
Warfarin: Vitamin K 10 mg IV (takes 6-24h). For urgent: 4-factor PCC (Kcentra) 25-50 units/kg (immediate). FFP only if PCC unavailable.
Dabigatran:Idarucizumab (Praxbind) 5g IV -immediate, complete reversal. RE-VERSE AD, 2017
Heparin: Protamine 1 mg per 100 units UFH given in last 2-3h (max 50 mg). Only 60% effective for LMWH.
Supratherapeutic INR management: INR 4.5-10, no bleeding: hold warfarin, recheck INR in 24-48h. Consider vitamin K 1-2.5 mg PO if high bleeding risk. INR > 10, no bleeding: vitamin K 5-10 mg PO, recheck in 24h. ANY INR + serious/life-threatening bleeding: 4-factor PCC 25-50 U/kg + vitamin K 10 mg IV + hold warfarin. FFP only if PCC unavailable (slower, volume overload).
Red Clot vs White Clot: Matching the Drug to the Thrombus
One rule sets up every triple-therapy decision: fast flow = platelets = antiplatelet; slow flow = fibrin = anticoagulant. Clot composition is dictated by flow physiology (Virchow). Under high arterial shear, von Willebrand factor unfolds and platelets drive the clot; under venous stasis (or a stagnant LA appendage) the coagulation cascade runs to completion and fibrin traps red cells. One drug class cannot cover both, which is exactly why a patient with AF (a fibrin problem) who gets a stent (a platelet problem) transiently needs both.
Don't cross the streams: AF cardioembolism is fibrin-rich, so an antiplatelet is inferior to an anticoagulant for stroke prevention ACTIVE-W, 2006. Conversely, antiplatelets remain the backbone for stents and ruptured plaque because an anticoagulant alone does not prevent stent thrombosis. Triple therapy exists only for the patient who legitimately has one of each problem at the same time, which is the scenario below.
AF + Recent PCI/ACS: Combining Anticoagulant + Antiplatelet
Triple therapy = oral anticoagulant (OAC) + aspirin + P2Y12 inhibitor (clopidogrel). It is indicated only when one patient simultaneously carries an anticoagulation indication AND a dual-antiplatelet (DAPT) indication, that is, two distinct clot problems at once (red clot + white clot, above). Neither drug class alone covers both, which is why all three are stacked, but only briefly.
Needs an anticoagulant (the OAC)
...PLUS needs DAPT (aspirin + P2Y12)
AF with elevated stroke risk (CHA₂DS₂-VASc)
PCI with coronary stent (the dominant reason)
Recent VTE (DVT/PE) on ongoing anticoagulation Treat ≥ 3 months (provoked by a transient factor) or extended/indefinite (unprovoked or persistent risk). Recurrence is steepest in the first 3 months, the high-risk "recent" window that justifies the overlap.
Acute coronary syndrome: STEMI / NSTEMI
Mechanical heart valve (warfarin, not a DOAC)
LV thrombus (akinetic segment post-MI)
The overlap is the indication: a left-column reason AND a right-column reason in the same patient. The textbook case is AF (left) who undergoes PCI/stenting for ACS (right). Once you have identified that overlap, the entire goal is to spend as little time on triple therapy as possible and de-escalate as below.
Default = double therapy: a DOAC + one P2Y12 inhibitor (clopidogrel), drop aspirin early. Add aspirin (triple therapy) only for the peri-PCI window. Why:AUGUSTUS, 2019 showed that once a DOAC + P2Y12 are on board, aspirin just adds bleeding with no ischemic benefit.
Phase
Regimen
Why
Peri-PCI (in-hospital, up to ~1 week)
Triple: DOAC + clopidogrel + aspirin
Stent-thrombosis risk is highest early, so a brief aspirin overlap is justified (longer only if very high ischemic risk).
2023 AF guideline: stable CAD beyond 1 year → anticoagulant alone; adding any antiplatelet only adds bleeding.
Agent choices: DOAC preferred over warfarin (apixaban has the strongest evidence here). The P2Y12 of choice is clopidogrel -ticagrelor and prasugrel add bleeding when combined with an anticoagulant and are generally avoided. If warfarin must be used, target INR 2.0-2.5 with a high time-in-range.
Anticoagulation in Pregnancy
LMWH is the anticoagulant of choice in pregnancy -it does not cross the placenta, so there is no teratogenic or fetal-bleeding risk. DOACs are contraindicated and warfarin is avoided, except for the specific mechanical-valve role below.
Agent
Use in pregnancy
Why
LMWH (enoxaparin, dalteparin)PREFERRED
First-line for VTE treatment and prophylaxis and for most indications, all trimesters. Weight-based dosing; check anti-Xa in obesity, renal impairment, or mechanical valves.
Does NOT cross the placenta, so no fetal harm. Predictable outpatient SQ dosing, no INR monitoring.
UFH
When rapid reversibility is needed (peri-delivery), severe renal failure (CrCl < 30), or in the window just before neuraxial anesthesia.
Also does not cross the placenta. Short half-life and protamine-reversible, which is why it is favored around delivery.
WarfarinAVOID (valve exception)
Avoid in general. Retained only for mechanical heart valves in the 2nd and 3rd trimesters (ACC/AHA and ESC class IIa), then switched to LMWH/UFH at ~36 weeks before delivery.
Crosses the placenta → warfarin embryopathy (nasal hypoplasia, stippled epiphyses) at weeks 6-12, plus later fetal CNS injury and intracranial bleeding. But it is the most effective at preventing valve thrombosis, so maternal risk can outweigh fetal risk for mechanical valves.
Cross the placenta; inadequate safety data with signals of fetal harm. No role even in mechanical valves.
Fondaparinux
Second-line, only if HIT or LMWH allergy/intolerance.
Minimal placental transfer but limited pregnancy data, so reserved for when heparins cannot be used.
Mechanical heart valve in pregnancy = highest-risk scenario. Three accepted strategies (shared decision-making): (1) dose-adjusted LMWH throughout (BID to a peak anti-Xa 1.0-1.2 IU/mL, or TID targeting trough 0.6-0.7); (2) LMWH in the 1st trimester (weeks 6-12, to avoid embryopathy) then warfarin in the 2nd/3rd; or (3) warfarin throughout if the required dose is low (≤ 5 mg/day carries the lowest fetal risk). Switch to UFH/LMWH at ~36 weeks so the fetus is not warfarin-anticoagulated during delivery. ESC, 2025
Delivery and breastfeeding: Hold LMWH ≥ 24h before planned delivery or neuraxial anesthesia (≥ 12h for a prophylactic dose). Warfarin, UFH, and LMWH are all compatible with breastfeeding (not secreted in clinically significant amounts); DOACs are not recommended while breastfeeding.
💊 Medications
Medications
Warfarin (Coumadin)
Individualized (typically 2-10 mg daily)
PO
Required for mechanical valves + APS. INR monitoring. Drug/food interactions. Vitamin K dependent factors (II, VII, IX, X, protein C/S).
Heparin (UFH)
80 U/kg bolus → 18 U/kg/hr
IV
Titratable, short half-life, dialyzable. Monitor aPTT q6h. Protamine for reversal. HIT risk.
Enoxaparin (Lovenox)
1 mg/kg BID or 1.5 mg/kg daily
SQ
Predictable pharmacokinetics. Avoid if CrCl < 30 (accumulates). Anti-Xa for monitoring in special populations.
4-Factor PCC (Kcentra)
25-50 U/kg IV
IV
Warfarin reversal (immediate). Also used off-label for Xa inhibitor reversal. Contains factors II, VII, IX, X + protein C/S.
DOAC dosing by indication: Apixaban: AF = 5 mg BID (2.5 mg if >= 2 of: age >= 80, weight <= 60 kg, Cr >= 1.5). VTE = 10 mg BID x 7d then 5 mg BID. Rivaroxaban: AF = 20 mg daily WITH FOOD (bioavailability drops 39% without food). VTE = 15 mg BID x 21d then 20 mg daily. Edoxaban: 60 mg daily (30 mg if CrCl 15-50 or weight <= 60 kg). Requires 5-day heparin lead-in. ARISTOTLE, 2011
🩸 HIT
Heparin-Induced Thrombocytopenia (HIT)
HIT is a prothrombotic emergency, not a bleeding problem. IgG antibodies form against platelet factor 4 (PF4)-heparin complexes and activate platelets, causing thrombocytopenia AND thrombosis at the same time. Despite the low platelet count, the danger is clot (venous > arterial, limb gangrene, stroke, MI), not bleeding -so the treatment is MORE anticoagulation, just not with heparin.
When to suspect it: a platelet drop > 50% from baseline (or new thrombosis) 5-10 days after starting heparin. Rapid onset (< 24h) if there was heparin exposure within the prior ~100 days (pre-formed antibodies). More common with UFH > LMWH and in surgical > medical patients.
First exclude pseudothrombocytopenia. EDTA (purple-top) tubes can trigger in-vitro platelet clumping from EDTA-dependent agglutinins, giving a falsely low automated count in a well patient. If the drop is isolated and unexpected, check the peripheral smear for platelet clumps and redraw in a sodium citrate (blue-top) tube -a normal count on the citrate sample confirms a lab artifact, not true thrombocytopenia, and spares an unnecessary HIT workup.
4T Score (pre-test probability)
Feature
2 points
1 point
0 points
Thrombocytopenia
Fall > 50% AND nadir ≥ 20K
Fall 30-50% or nadir 10-19K
Fall < 30% or nadir < 10K
Timing
Day 5-10 (or ≤ 1 day if heparin within 30 days)
> Day 10 or timing unclear
< Day 4, no recent heparin
Thrombosis
New thrombosis, skin necrosis, or post-bolus systemic reaction
Progressive/recurrent or suspected thrombosis
None
oTher cause
None apparent
Possible
Definite other cause
0-3 = low (HIT effectively excluded, do not test) · 4-5 = intermediate · 6-8 = high. Send antibody testing only if intermediate or high.
Confirming the Diagnosis
Step 1, PF4-heparin antibody ELISA (immunoassay): highly sensitive, so a negative result rules HIT out. A positive is less specific (many antibodies are non-pathogenic); a higher optical density makes true HIT more likely.
Step 2, serotonin release assay (SRA): the functional gold standard, highly specific, confirms pathogenic antibodies. Do not wait for it before acting.
Management
Act on clinical suspicion, do not wait for confirmatory testing.
STOP all heparin -UFH and LMWH, SQ prophylaxis, line flushes, and heparin-bonded catheters. Why: any heparin keeps fueling antibody-mediated platelet activation.
Start a non-heparin anticoagulant immediately at therapeutic dose: argatroban (hepatic clearance, use in renal failure), bivalirudin, fondaparinux, or a DOAC (increasingly used for stable HIT). Why: HIT is prothrombotic, so simply stopping heparin is not enough, the clot risk persists for weeks.
Do NOT start warfarin until platelets recover (> 150K).Why: warfarin acutely drops protein C and triggers venous limb gangrene / skin necrosis in the prothrombotic HIT state. If the patient is already on warfarin, reverse it with vitamin K and overlap a non-heparin agent.
Do NOT give prophylactic platelet transfusions.Why: it adds fuel to thrombosis; reserve platelets for active bleeding only.
Duration: anticoagulate 4 weeks for isolated HIT (until platelet recovery) and 3 months if thrombosis occurred (HITT). Document a heparin allergy and avoid re-exposure.
🏥 Rounds
Pimp Questions
❓ When should you bridge anticoagulation perioperatively and when should you not?
Do NOT bridge most patients.BRIDGE, 2015 showed that bridging AF patients on warfarin with LMWH increased major bleeding 3-fold without reducing stroke.Bridge ONLY: mechanical mitral valve, mechanical aortic valve + additional risk factor (AF, prior stroke, EF < 35%), VTE within 3 months, prior thromboembolism during anticoagulation interruption.
❓ Why are DOACs preferred over warfarin for nonvalvular AF?
Four landmark trials showed DOACs are non-inferior or superior to warfarin for stroke prevention with lower rates of intracranial hemorrhage: RE-LY (dabigatran), ROCKET AF (rivaroxaban), ARISTOTLE (apixaban -also reduced mortality), ENGAGE AF (edoxaban). Additional advantages: no INR monitoring, fewer food/drug interactions, predictable pharmacokinetics, rapid onset.
❓ How do you reverse each anticoagulant?
Warfarin: Vitamin K 10 mg IV (slow, 6-24h) + 4-factor PCC 25-50 U/kg (immediate). Dabigatran: Idarucizumab 5g IV (immediate, complete). Xa inhibitors: Andexanet alfa (expensive) or 4F-PCC 50 U/kg (off-label). Heparin: Protamine 1 mg/100 U UFH. LMWH: Protamine partially effective (~60%). For all: hold drug, apply pressure, transfuse if needed.
❓ Why is warfarin preferred over DOACs in antiphospholipid syndrome?
TRAPS, 2018 -trial of rivaroxaban vs warfarin in triple-positive APS was stopped early for excess thrombotic events in the rivaroxaban arm (arterial events). DOACs may be acceptable for single/double-positive APS with venous-only events, but triple-positive APS must be on warfarin. Warfarin is also required for mechanical heart valves (DOACs showed excess valve thrombosis in RE-ALIGN).
❓ What is the CHA₂DS₂-VASc score and when do you anticoagulate?
C HF (1) · H TN (1) · A ge ≥ 75 (2) · D M (1) · S troke/TIA (2) · V ascular disease (1) · A ge 65-74 (1) · S ex female (1). Score 0 (men) or 1 (women): no anticoagulation. Score 1 (men) or 2 (women): consider. Score ≥ 2 (men) or ≥ 3 (women): anticoagulate. DOAC preferred unless valvular AF or APS.
❓ A patient on warfarin has an INR of 8.5 with no bleeding. How do you manage this?
Hold warfarin + give vitamin K 2.5-5 mg PO (oral is preferred over IV for non-bleeding supratherapeutic INR). Recheck INR in 24h. Do NOT give PCC or FFP (no active bleeding). If INR > 10 without bleeding, give vitamin K 5-10 mg PO. Resume warfarin at a reduced dose once INR < 3. Common causes of supratherapeutic INR: drug interaction (antibiotics, amiodarone, azole antifungals), dietary change (decreased vitamin K intake), liver disease, alcohol binge.
❓ What are the absolute contraindications to anticoagulation?
Active life-threatening hemorrhage, hemorrhagic stroke (acute phase), severe uncontrolled hypertension (relative), intracranial hemorrhage, major surgery within 24h, platelet count < 25K (relative at < 50K), active GI bleeding. For patients with both high thrombotic AND high bleeding risk (e.g., recent GI bleed + mechanical valve), consult hematology. An IVC filter may be a temporary bridge if anticoagulation must be held. HAS-BLED score >= 3 = high bleeding risk but is NOT a contraindication to anticoagulation.
❓ When should you use heparin drip vs LMWH vs a DOAC for acute VTE?
Heparin drip: when you need tight control and rapid reversibility - Category E PE (may need tPA), high bleeding risk, renal failure (CrCl < 30), perioperative patients. LMWH: stable VTE, predictable dosing, can discharge on it. DOACs: stable VTE for discharge - apixaban or rivaroxaban need no heparin lead-in (load and go). Edoxaban/dabigatran need 5-day heparin lead-in first. Cancer VTE: LMWH or edoxaban/rivaroxaban (not warfarin). AMPLIFY, 2013
❓ How do you manage a patient on a DOAC who needs emergency surgery?
Check last dose timing. If last dose < 24h ago AND high-risk surgery: consider reversal (idarucizumab for dabigatran, andexanet alfa or 4F-PCC 50 U/kg for Xa inhibitors). If last dose > 24-48h ago: most DOACs are sufficiently cleared for surgery (longer washout if CrCl reduced). For urgent but not emergent surgery: delay 24-48h if possible. Drug-specific half-lives: dabigatran 12-17h, rivaroxaban 5-13h, apixaban 12h, edoxaban 10-14h. All are prolonged in renal impairment. Standard coagulation tests (PT/INR) do NOT reliably reflect DOAC activity.
Clinical Examples
📋 Case 1, Perioperative Bridging Decision
Patient: 72M, on warfarin for mechanical aortic valve (INR target 2.5-3.5), needs elective hip replacement in 5 days. Current INR 3.0.
Key findings: Mechanical valve = high thromboembolic risk. CHA2DS2-VASc not applicable (valvular indication). No prior stroke or TIA. EF 55%.
Management:
Stop warfarin 5 days pre-op (allow INR to drift to < 1.5)
Mechanical valve = MUST bridge with therapeutic LMWH (enoxaparin 1 mg/kg BID) when INR < 2
Hold LMWH 24h before surgery
Resume warfarin evening of surgery; restart LMWH 24-48h post-op when hemostasis confirmed
Stop LMWH when INR therapeutic (≥ 2.5 for mechanical valve)
Teaching point: Most AF patients do NOT need bridging. BRIDGE, 2015 showed bridging AF patients increased major bleeding 3-fold without reducing stroke. However, mechanical valves remain an absolute bridging indication due to catastrophic thrombotic risk.
📋 Case 2, DOAC Reversal for Life-Threatening Bleeding
Patient: 78F, on apixaban 5 mg BID for AF, presents with massive upper GI bleed (hematemesis, melena). Hemodynamically unstable.
Key findings: HR 118, BP 82/50. Hgb 6.2 (baseline 11.8). INR 1.3 (misleading on DOACs). Last apixaban dose 4 hours ago. Anti-Xa level 180 ng/mL (supratherapeutic).
Management:
Hold apixaban immediately
Reversal: andexanet alfa (Andexxa) IV bolus + infusion if available; otherwise 4-factor PCC 50 U/kg (off-label)
Transfuse pRBC to Hgb > 7; FFP does NOT reverse DOACs
Emergent EGD once hemodynamically stabilized
After bleed resolved: reassess anticoagulation indication and risks vs benefits of resumption
Teaching point: Standard INR does NOT reliably reflect DOAC activity. Anti-Xa levels assess rivaroxaban/apixaban; thrombin time for dabigatran. Andexanet alfa reverses Xa inhibitors but is expensive. 4-factor PCC is the pragmatic alternative. ANNEXA-4, 2019
📋 Case 3, Warfarin-Only Indication in APS
Patient: 34F, triple-positive antiphospholipid syndrome (lupus anticoagulant + anti-cardiolipin + anti-beta2-glycoprotein I), history of DVT + PE at age 28. On rivaroxaban 20 mg daily. Presents with acute left MCA stroke.
Key findings: CT head: no hemorrhage. CTA: left MCA occlusion. Thrombectomy performed. INR 1.1 despite rivaroxaban. Anti-Xa level therapeutic (ruling out non-adherence).
Management:
This is a treatment failure on a DOAC in triple-positive APS
Switch to warfarin (INR target 2-3, some experts target 3-4 for arterial events)
Bridge with UFH drip until INR therapeutic
DOACs are contraindicated in triple-positive APS
Lifelong anticoagulation with warfarin - never switch to DOAC
Teaching point:TRAPS, 2018 was stopped early because rivaroxaban had significantly more arterial thrombotic events than warfarin in triple-positive APS. Warfarin is also the only option for mechanical heart valves (RE-ALIGN, 2013 showed excess valve thrombosis with dabigatran).
Sample Presentation
Mr. Davis is a 74-year-old man on warfarin for mechanical aortic valve (INR target 2.5-3.5) admitted for cholecystectomy. Current INR 3.1. Surgery planned in 3 days. Question: how do you manage his anticoagulation perioperatively?
Key Points: Mechanical valve = high thromboembolic risk → bridge with therapeutic LMWH. Stop warfarin now (5 days pre-op). Start enoxaparin 1 mg/kg BID when INR < 2. Hold LMWH 24h pre-surgery. Restart heparin drip post-op when hemostasis confirmed (12-24h). Resume warfarin evening of surgery. Stop heparin when INR therapeutic.
Monitoring
Warfarin INR: daily inpatient → weekly → q2-4 weeks when stable. Time in therapeutic range (TTR) target > 65%.
Heparin aPTT: q6h after initiation or dose change until 2 consecutive values in range, then q12-24h.
DOACs: Cr annually (more frequent if CKD). No routine drug levels. CBC at baseline + annually.
HIT screening: platelet count q2-3 days on UFH × first 14 days. 4T score if platelet drop.
CHA₂DS₂-VASc reassessment: annually for AF patients -score can change (new DM, HF, age threshold).
📋 Summary
Summary
Match the Drug to the Clot
Red clot, fibrin- and red-cell-rich, forms in low-flow venous systems and the fibrillating atrium, and is treated with anticoagulants.White clot, platelet-rich, forms in high-shear arterial vessels and on ruptured plaque, and is treated with antiplatelets.Using the wrong class is a common and consequential error: aspirin does not treat a DVT, and warfarin does not prevent stent thrombosis.
DOACs Are the Default, With Named Exceptions
Preferred for atrial fibrillation and for VTE: fixed dosing, no routine monitoring, fewer interactions, less intracranial hemorrhage.Use warfarin instead for mechanical valves, moderate-to-severe mitral stenosis, and antiphospholipid syndrome (TRAPS showed rivaroxaban inferior). Also use caution in severe renal impairment, extremes of body weight and pregnancy.
Get the DOAC Dose Reduction Right
Each agent has its own criteria and they are not interchangeable: apixaban reduces on two of three (age 80 or above, weight 60 kg or below, creatinine 1.5 or above), while rivaroxaban and edoxaban reduce by creatinine clearance. Inappropriate dose reduction is as harmful as overdosing, because it leaves the patient unprotected while everyone believes they are anticoagulated.
Most Patients Do Not Need Bridging
BRIDGE showed no-bridging was non-inferior for thromboembolism with significantly less major bleeding in atrial fibrillation.Reserve bridging for high thrombotic risk: mechanical mitral valve, recent stroke or VTE within 3 months, and antiphospholipid syndrome. DOACs never need bridging given their short half-life; just stop them 24 to 48 h before.
Know the Reversal Agents
Warfarin: 4-factor PCC plus vitamin K, PCC over plasma for speed and volume. Dabigatran: idarucizumab.Apixaban and rivaroxaban: andexanet alfa, or PCC where unavailable.Heparin: protamine (only partially effective for LMWH). Reverse for life-threatening bleeding, not for an abnormal number.
Simplify Triple Therapy After PCI
In atrial fibrillation plus PCI, drop aspirin early, typically within a week, and continue an oral anticoagulant plus clopidogrel.Prolonged triple therapy bleeds far more than it prevents, and the trials consistently favored the shorter, dual regimen. Use a DOAC rather than warfarin where possible.
Pregnancy Is LMWH Territory
Warfarin is teratogenic and DOACs are contraindicated, since they cross the placenta and safety data are lacking. Use LMWH throughout, which does not cross the placenta, and plan the peripartum interruption in advance with obstetrics and anesthesia, since neuraxial anesthesia requires a defined interval since the last dose.
Think About Whether to Anticoagulate at All
Score the thrombotic risk with CHA2DS2-VASc and the bleeding risk with HAS-BLED, but use HAS-BLED to identify modifiable factors, not as a reason to withhold treatment.Set a duration and a review date, because indefinite anticoagulation started for a provoked event is one of the commoner sources of avoidable bleeding. Any heparin exposure with a falling platelet count means consider HIT, stop all heparin including flushes, and start a non-heparin agent.
Anemia = Hgb < 13 (men) or < 12 (women). Affects ~25% of hospitalized patients. The approach is MCV-driven: Microcytic (MCV < 80): iron deficiency (#1 worldwide), thalassemia, anemia of chronic disease (can be micro or normo), sideroblastic, lead poisoning. Normocytic (MCV 80-100): anemia of chronic disease/inflammation (#1 inpatient), acute blood loss, hemolysis, CKD (EPO deficiency), mixed deficiency. Macrocytic (MCV > 100): B12/folate deficiency, MDS, alcohol/liver disease, hypothyroidism, medications (methotrexate, hydroxyurea, AZT). The reticulocyte count is the most underordered and most important second test -it tells you whether the marrow is responding appropriately (high retic = destruction/loss) or failing (low retic = production problem).
Iron deficiency + chronic disease: ferritin 30-100 (unreliably elevated by inflammation), TIBC variable. Check soluble transferrin receptor (sTfR) -elevated = true iron deficiency even with inflammation.
🚨 Management
Management
Iron deficiency anemia:
Oral: ferrous sulfate 325 mg (65 mg elemental Fe) every other day on empty stomach with vitamin C IRON-MIDE, 2020. Every-other-day dosing is as effective as daily (hepcidin rebound). Avoid with PPIs, calcium, coffee.
IV iron: if oral intolerant, CKD, inflammatory bowel disease, Hgb < 7, or pre-surgical. Iron sucrose 200 mg × 5 doses or ferric carboxymaltose 750 mg × 2 or low-molecular-weight iron dextran 1000 mg × 1 (single dose, monitor for anaphylaxis × 1h).
Always find the source: premenopausal women → menstrual loss. Men or postmenopausal → GI source until proven otherwise (EGD + colonoscopy). Celiac screening if no GI source found.
B12 deficiency: IM cyanocobalamin 1000 mcg daily × 7d → weekly × 4wk → monthly lifelong. High-dose oral (1000-2000 mcg/day) is an alternative for compliant patients without malabsorption.
Anemia of chronic disease: Treat underlying condition. EPO-stimulating agents (epoetin alfa, darbepoetin) for CKD (target Hgb 10-11, not higher [TREAT, CREATE]). IV iron if concurrent iron deficiency (TfSat < 20%, ferritin < 100).
Transfusion: Hgb < 7 (restrictive threshold TRICC, 1999). < 8 if ACS or symptomatic. 1 unit at a time → recheck.
💊 Medications
Medications
Drug
Dose
Route
Notes
Ferrous sulfate
325 mg (65 mg elemental) every other day
PO
Empty stomach + vitamin C for absorption. Every-other-day = daily efficacy with fewer GI SEs. Avoid PPIs, Ca, coffee. IRON-MIDE, 2020
Epoetin alfa
50-300 IU/kg TIW
SQ
CKD anemia (target Hgb 10-11). VTE risk if Hgb > 11. Iron replete first (TfSat > 20%, ferritin > 100). TREAT, 2009
🏥 Rounds
Pimp Questions
❓ What is the most important second test after CBC in anemia workup?
Reticulocyte count. It differentiates production problems (low retic: marrow failure, nutrient deficiency) from destruction/loss (high retic: hemolysis, bleeding). Calculate the reticulocyte index (RI) = retic % × (patient Hgb / normal Hgb) ÷ maturation factor. RI > 2 = appropriate marrow response. RI < 2 = inadequate. Most underordered test in anemia workup.
❓ How do you diagnose iron deficiency in a patient with concurrent inflammation?
Ferritin is an acute phase reactant -inflammation falsely elevates it. A "normal" ferritin of 60 in a patient with CRP of 80 may actually represent iron deficiency. Rules: (1) ferritin < 30 = iron deficient regardless of inflammation. (2) Ferritin 30-100 with inflammation = likely iron deficient. (3) Best additional test: soluble transferrin receptor (sTfR) -elevated in true iron deficiency, NOT affected by inflammation. TfSat < 20% also supports iron deficiency.
❓ Why should oral iron be taken every other day rather than daily?
IRON-MIDE, 2020 demonstrated that every-other-day dosing is as effective as daily for iron repletion. The mechanism: an oral iron dose triggers hepcidin release (iron-regulatory hormone) that peaks at 24h and blocks iron absorption for ~48h. A second daily dose is largely not absorbed and only causes GI side effects (nausea, constipation). Every-other-day dosing allows hepcidin to fall between doses → better absorption per dose with fewer side effects.
❓ When must you find the source of iron deficiency anemia?
Always in men and postmenopausal women -GI malignancy (colon cancer) until proven otherwise. Get EGD + colonoscopy. In premenopausal women, menstrual loss is the most common cause, but if heavy menstruation doesn't explain the severity, or if there are GI symptoms → scope. Also consider: celiac disease (anti-TTG), gastric bypass (iron absorption site bypassed), chronic NSAID use (GI erosions).
❓ What peripheral smear findings help differentiate causes of anemia?
EGD + colonoscopy: cecal mass found, biopsy confirmed adenocarcinoma
Teaching point: New iron deficiency anemia in a man or postmenopausal woman = GI malignancy until proven otherwise. Never just replace iron without finding the source.
📋 Case 2, B12 Deficiency Mimicking Leukemia
Patient: 45-year-old woman with history of gastric bypass presents with fatigue, paresthesias in feet, and unsteady gait for 6 months.
IM cyanocobalamin 1000 mcg daily x 7 days, then weekly x 4 weeks, then monthly lifelong
Monitor for reticulocyte crisis at day 5-7
Monitor potassium and phosphate (drop during rapid erythropoiesis)
Teaching point: Severe B12 deficiency causes pancytopenia mimicking leukemia. Always check B12 before bone marrow biopsy. Hypersegmented neutrophils are pathognomonic for megaloblastic anemia. Neurologic damage may be irreversible.
📋 Case 3, Mixed Anemia of Chronic Disease + Iron Deficiency
Patient: 58-year-old man with rheumatoid arthritis on methotrexate admitted for flare. Hgb 9.4, MCV 82.
Key findings: Ferritin 85 (ambiguous in inflammation), TIBC 220 (low), TfSat 15%, CRP 68, soluble transferrin receptor (sTfR) elevated at 4.2. Reticulocyte index 0.8.
Management:
Elevated sTfR confirms concurrent iron deficiency despite "normal" ferritin
IV iron sucrose 200 mg x 5 doses (oral poorly absorbed in active inflammation)
Treat underlying RA flare to reduce hepcidin-mediated iron sequestration
Teaching point: Ferritin is an acute phase reactant. A "normal" ferritin of 85 with CRP of 68 likely represents iron deficiency. In inflammation, ferritin less than 100 is suggestive of concurrent iron deficiency. sTfR is the best differentiating test.
Sample Presentation
Mrs. Martinez is a 52-year-old postmenopausal woman presenting with fatigue × 3 months. No bleeding, no melena. PMH: GERD on omeprazole. Labs: Hgb 8.2, MCV 72, ferritin 8, TIBC 450, TfSat 8%, reticulocyte index 0.5%.
Key Points: Classic iron deficiency anemia -microcytic, low ferritin, high TIBC, low TfSat, low retic (production problem). Postmenopausal woman = GI source until proven otherwise. Needs EGD + colonoscopy. Start oral iron (every other day with vitamin C). Consider IV iron if oral intolerant or Hgb < 7. Celiac screen (anti-TTG) if GI workup negative. PPI may impair iron absorption.
Reticulocyte count at day 5-7 -after starting B12 or iron. Expected "retic crisis" = brisk reticulocytosis confirming marrow response.
CBC + reticulocyte at 2-4 weeks -Hgb should begin rising. If not → reassess diagnosis, compliance, concurrent iron deficiency.
Ferritin at 8-12 weeks -on oral iron. Target ferritin > 100 (or > 200 in CKD). Continue oral iron 3-6 months after Hgb normalizes to replete stores.
K⁺, PO₄ -drop during rapid erythropoiesis (B12 repletion, EPO therapy). Monitor and replace.
Iron studies before EPO -functional iron deficiency is #1 cause of EPO resistance. TfSat < 20% or ferritin < 100 → give IV iron.
Hemolysis markers -if autoimmune: DAT, LDH, haptoglobin, reticulocyte count. Trending LDH is the simplest way to monitor hemolytic activity.
📋 Summary
Summary
Start With the MCV
Microcytic below 80, normocytic 80 to 100, macrocytic above 100.The MCV is an average, so a mixed deficiency (iron plus B12) can produce a perfectly normal MCV. A wide RDW is the clue that two populations are present, and the smear confirms it.
Always Get a Reticulocyte Count
It separates the two mechanisms in one test.Low means underproduction (deficiency, marrow disease, anemia of chronic disease, renal failure). High means destruction or loss (hemolysis or bleeding). It takes 3 to 5 days to rise, so an early normal count after an acute bleed is not reassurance.
Microcytic: Iron Deficiency Until Proven Otherwise
Ferritin is the single best test; below 30 confirms deficiency.Ferritin is an acute phase reactant, so inflammation raises it: with active inflammation a value up to about 100, or a transferrin saturation below 20%, still supports deficiency. Then thalassemia (a very low MCV with a near-normal hemoglobin and normal iron studies), anemia of chronic disease, sideroblastic anemia, lead.
Iron Deficiency Is a Symptom, Not a Diagnosis
Find the source.In any man, or any postmenopausal woman, iron deficiency is gastrointestinal blood loss until proven otherwise and needs endoscopy in both directions. In premenopausal women, menorrhagia is the usual cause, but do not stop looking if the history does not fit. Also consider celiac disease and H. pylori as malabsorptive causes.
Dose Oral Iron Every Other Day
Ferrous sulfate 325 mg (65 mg elemental) every other day.Daily dosing raises hepcidin, which blocks absorption of the next dose, so alternate-day dosing achieves equal or better absorption with far fewer GI side effects. Give on an empty stomach with vitamin C, and separate from PPIs, calcium and tea. IV iron for malabsorption, intolerance, ongoing loss or CKD.
Macrocytic: Split It Megaloblastic or Not
Megaloblastic (B12, folate): hypersegmented neutrophils, high LDH, high indirect bilirubin from ineffective erythropoiesis.Non-megaloblastic: alcohol, liver disease, hypothyroidism, myelodysplasia, drugs (methotrexate, hydroxyurea, zidovudine, antiepileptics). Check methylmalonic acid when B12 is borderline, since it is more sensitive than the B12 level itself.
Give B12 Before Folate, Not After
Folate corrects the anemia in B12 deficiency but does nothing for the neurologic damage, which then progresses irreversibly (subacute combined degeneration). Check both, and replace B12 first. Ask about metformin, PPIs, gastrectomy, ileal disease and a vegan diet.
Normocytic: Use the Retic to Branch
Low retic: anemia of chronic disease (low iron with a low or normal TIBC and a normal or high ferritin), chronic kidney disease (erythropoietin deficiency), early iron deficiency, marrow infiltration.High retic: hemolysis or bleeding, so send LDH, haptoglobin, bilirubin and a Coombs test. Transfuse restrictively, above 7 g/dL (above 8 in acute coronary syndrome), and use erythropoiesis-stimulating agents only in CKD, iron-replete, targeting 10 to 11 g/dL, since higher targets increase thrombosis and death.
Flow cytometry -if PNH suspected (dark urine, pancytopenia, abdominal vein thrombosis). Tests for CD55/CD59 (GPI-anchored proteins absent in PNH).
G6PD level -check BETWEEN episodes (level is falsely normal during acute hemolysis because young RBCs have more G6PD). Common triggers: sulfa drugs, dapsone, fava beans, infections.
Cold agglutinin titer -if DAT positive for complement only (C3d) with IgG negative. Associated with Mycoplasma pneumonia, EBV, lymphoma.
Osmotic fragility -hereditary spherocytosis (spherocytes lyse more easily in hypotonic solution)
🚨 Management
Management
Warm AIHA (DAT positive, IgG):
First-line: Prednisone 1 mg/kg daily → taper when Hgb stabilizing. Response in 70-85% within 1-3 weeks.
Second-line: Rituximab 375 mg/m² × 4 (steroid-refractory or relapsing). Also consider: mycophenolate, azathioprine. Lechner & Jäger, 2015
Third-line: Splenectomy (if failing medical therapy). Vaccinate before surgery.
Transfuse if life-threatening anemia -DO transfuse despite positive DAT making crossmatch difficult. Use "least incompatible" units. The blood bank will work with you.
Cold agglutinin disease (DAT positive, C3d):Keep patient warm (avoid cold exposure, warm IV fluids). Steroids less effective than in warm AIHA. Rituximab first-line. Sutimlimab (anti-C1s complement inhibitor) for chronic CAD CARDINAL, 2022. Avoid RBC transfusion if possible (complement activates on transfused cells).
TTP/HUS: See TTP topic (PLEX, steroids, caplacizumab). HERCULES, Scully 2019
❓ What is the difference between intravascular and extravascular hemolysis?
Intravascular: RBCs destroyed IN the circulation → free hemoglobin released → hemoglobinuria (dark/red urine), hemoglobinemia, very low haptoglobin (consumed binding free Hgb), hemosiderinuria. Causes: TTP, DIC, PNH, transfusion reaction, mechanical valve. Extravascular: RBCs destroyed by splenic macrophages → splenomegaly, jaundice (indirect bili), no hemoglobinuria. Causes: AIHA, hereditary spherocytosis, sickle cell, hypersplenism.
❓ Should you withhold transfusion in AIHA because the crossmatch is incompatible?
NO -transfuse if clinically indicated. In warm AIHA, autoantibodies react with virtually ALL donor RBCs, making all crossmatches "incompatible." The blood bank performs extended testing to identify any underlying alloantibodies (from prior transfusions). They provide "least incompatible" units. Transfused RBCs will be destroyed faster than normal, but they provide critical oxygen delivery. Life-threatening anemia always trumps crossmatch difficulty.
❓ Why should you check G6PD levels BETWEEN episodes, not during?
During acute hemolysis, the oldest RBCs (with the LOWEST G6PD activity) are selectively destroyed first. The remaining RBCs + reticulocytes have higher G6PD levels because they're younger → the G6PD level can be falsely normal during the attack. Wait 2-3 months after the episode for the RBC population to normalize, then check. If you must diagnose acutely, a level that is low DURING hemolysis is definitely diagnostic -but a normal level doesn't exclude G6PD deficiency.
❓ What is Evans syndrome?
Evans syndrome = AIHA + immune thrombocytopenia (ITP) (positive DAT + low platelets from antiplatelet antibodies). May also include autoimmune neutropenia. Commonly associated with SLE and lymphoproliferative disorders. More refractory than isolated AIHA or ITP. Treatment: steroids, rituximab, mycophenolate. Splenectomy less effective than in isolated ITP. Always check platelets in new AIHA.
❓ What is the most sensitive lab marker for hemolysis?
Haptoglobin. It binds free hemoglobin and is rapidly cleared by the liver during hemolysis → levels become undetectable. It is the first lab to become abnormal and the last to normalize. Sensitivity ~96%. However, it is also an acute phase reactant -can be falsely "normal" during concurrent inflammation. The combination of undetectable haptoglobin + elevated LDH has the highest sensitivity/specificity for hemolysis.
Clinical Examples
📋 Case 1, Warm Autoimmune Hemolytic Anemia (AIHA)
Patient: 45F with SLE presenting with fatigue, jaundice, dark urine × 5 days. Hgb 5.8 (baseline 11.5), retic 14%, LDH 620, haptoglobin < 10, indirect bili 5.1. DAT positive (IgG + C3d). Smear: spherocytes.
Key findings: Warm AIHA, IgG antibodies on DAT, spherocytes from splenic macrophage partial phagocytosis. SLE is the classic autoimmune association. Severe anemia requiring urgent treatment.
Management:
Prednisone 1 mg/kg/day (first-line, response in 60-80% within 1-3 weeks)
Transfuse pRBCs, do NOT withhold despite "incompatible" crossmatch (all units will be incompatible; blood bank provides "least incompatible")
If steroid-refractory or relapsing: rituximab 375 mg/m² weekly × 4 (second-line)
Check for Evans syndrome (AIHA + ITP), check platelet count
Teaching point: Never withhold transfusion in AIHA because the crossmatch is incompatible. All crossmatches will be incompatible, the autoantibody reacts with all RBCs. Transfused cells are destroyed faster but provide critical oxygen delivery.
📋 Case 2, Cold Agglutinin Disease
Patient: 68M with progressive fatigue and acrocyanosis (blue fingers/toes) in winter. Hgb 8.4, retic 8%, LDH 380, haptoglobin < 10. DAT positive (C3d only, IgG negative). Cold agglutinin titer 1:2048. SPEP: IgM kappa M-spike.
Key findings: Cold agglutinin disease, IgM antibodies bind RBCs at cold temperatures → complement activation → intravascular hemolysis. C3d-only DAT is the hallmark. IgM M-spike suggests underlying lymphoproliferative disorder (Waldenström's, marginal zone lymphoma).
Management:
Avoid cold exposure (the most important intervention, prevents antibody binding)
Steroids are INEFFECTIVE in cold agglutinin disease (unlike warm AIHA)
Rituximab ± bendamustine for symptomatic disease requiring treatment Berentsen, 2020
If transfusing: use blood warmer (cold blood triggers more agglutination)
Hematology workup: CT chest/abdomen/pelvis, bone marrow biopsy (rule out lymphoma)
Teaching point: Cold agglutinin disease is fundamentally different from warm AIHA, steroids don't work, splenectomy doesn't help (complement-mediated destruction is intravascular, not splenic). Treatment targets the B-cell clone producing the IgM.
📋 Case 3, G6PD Deficiency Hemolytic Crisis
Patient: 28M of Mediterranean descent with acute onset dark urine, back pain, jaundice 2 days after starting TMP-SMX for UTI. Hgb 7.2 (was 14), retic 2% (inappropriately low acutely), LDH 1200, haptoglobin < 10. DAT negative. Smear: bite cells, Heinz bodies on supravital stain.
Key findings: G6PD deficiency, oxidant stress (TMP-SMX) → Heinz body formation → splenic "biting" of Heinz bodies → bite cells. DAT negative distinguishes from AIHA. Low retic acutely because marrow hasn't responded yet (rises by day 5-7).
Management:
Stop the offending drug (TMP-SMX) immediately
Supportive care: IVF hydration, transfuse if symptomatic or Hgb < 7
Do NOT check G6PD level now (falsely normal during hemolysis, older cells already destroyed). Recheck in 2-3 months
Hemolysis is self-limited, resolves once offending agent removed and affected RBCs cleared
Teaching point: G6PD level during acute hemolysis can be falsely normal because the most deficient cells have already been destroyed. A "normal" level during crisis does NOT exclude G6PD deficiency. Always recheck between episodes.
Sample Presentation
Mrs. Okafor is a 48-year-old woman with SLE presenting with fatigue, jaundice, and dark urine × 5 days. Exam: pallor, scleral icterus, mild splenomegaly. Labs: Hgb 6.2 (baseline 11), retic 12%, LDH 580, haptoglobin < 10, indirect bili 4.2. DAT strongly positive (IgG + C3d). Smear: spherocytes.
Key Points: Warm AIHA (DAT positive IgG, spherocytes on smear) in the setting of SLE (classic association). Start prednisone 1 mg/kg. Transfuse -Hgb 6.2 is dangerously low, even though crossmatch will be difficult (blood bank uses "least incompatible" units). Folic acid 1 mg daily. Check for Evans syndrome (concurrent thrombocytopenia).
Hemolysis markers q1-2 days during acute episode: LDH (simplest trending marker), haptoglobin, reticulocyte count
Hgb daily during active hemolysis -transfuse if < 7 (or < 8 if symptomatic/cardiac)
DAT -recheck if clinical picture changes or treatment response unexpected
On steroids: blood glucose, BP, mood assessment, bone protection (calcium + vitamin D)
Cold agglutinin: titer levels, avoid cold triggers, monitor for worsening during winter
Folate level -chronic hemolysis depletes folate → megaloblastic crisis if not supplemented
📋 Summary
Summary
Establish That It Is Hemolysis
High LDH, high indirect bilirubin, low haptoglobin, high reticulocyte count.A low haptoglobin with a high LDH is the most useful pair, and a normal haptoglobin makes significant intravascular hemolysis unlikely. Reticulocytosis takes 3 to 5 days to develop, so a normal count early does not exclude it.
The Coombs Test Is the Branch Point
Direct antiglobulin test positive = immune: autoimmune, drug-induced or a transfusion reaction. Negative = non-immune: mechanical, an intrinsic red cell defect, infection or a toxin. Everything downstream follows from this single result.
Always Look at the Smear Yourself
Schistocytes mean a microangiopathy (TTP, HUS, DIC, a mechanical valve, malignant hypertension). Spherocytes mean warm autoimmune hemolysis or hereditary spherocytosis. Bite cells and Heinz bodies mean G6PD deficiency. Sickle cells, target cells, agglutination each point somewhere specific. The smear frequently makes the diagnosis before the serology returns.
Warm and Cold AIHA Behave Differently
Warm (IgG, extravascular, splenic): the commoner type, associated with lupus, CLL, lymphoma and drugs. Treat with prednisone 1 mg/kg, to which 70 to 85% respond, tapering slowly because a fast taper relapses.Cold agglutinin disease (IgM, complement-mediated): associated with Mycoplasma, EBV and lymphoproliferative disease. Steroids work poorly; keep the patient warm and use rituximab as first line.
Schistocytes Are a Stop-Everything Finding
Thrombocytopenia with schistocytes is TTP until proven otherwise, and TTP is fatal without urgent plasma exchange. Use the PLASMIC score, send ADAMTS13, and do not wait for the result to start exchange in a high-probability patient.Do not transfuse platelets in suspected TTP unless there is life-threatening bleeding: it fuels further microthrombosis.
Ask What the Patient Took and Where They Have Been
G6PD deficiency hemolyzes after oxidative stress from dapsone, primaquine, nitrofurantoin, rasburicase, sulfa drugs, fava beans or an acute infection. Test after the acute episode, because the level is falsely normal during a crisis once the older, most deficient cells have already lysed. Also consider malaria and babesiosis in the returning traveler, and drug-induced immune hemolysis from cephalosporins and penicillins.
Do Not Miss PNH
Hemolysis with thrombosis at unusual sites, cytopenias, and dark morning urine.Flow cytometry for CD55 and CD59 loss makes the diagnosis, and it is easily overlooked in a patient labeled as having aplastic anemia or unexplained hemolysis. Eculizumab controls it, but it blocks terminal complement, so meningococcal vaccination at least 2 weeks before the first dose plus antibiotic prophylaxis is mandatory.
Supportive Care With Two Cautions
Give folate, since high turnover consumes it, and treat iron loss in chronic intravascular hemolysis. Crossmatching may be difficult or impossible in AIHA, so involve the blood bank early and do not withhold transfusion from an unstable patient because the units are incompatible: least-incompatible blood is safer than untreated anemia. Screen for the underlying disorder, since AIHA is frequently secondary to lymphoproliferative disease, lupus or a drug rather than idiopathic.
Bradykinesia plus rest tremor or rigidity from loss of nigral dopaminergic neurons. Levodopa is the most effective therapy, and the two things that hurt hospitalized patients most are late or held doses and dopamine-blocking drugs. Orthostatic hypotension is the under-recognized cause of falls in these patients.
🔍 Overview
Overview
Parkinson disease (PD) is the second most common neurodegenerative disease after Alzheimer disease. Progressive loss of dopaminergic neurons in the substantia nigra pars compacta with alpha-synuclein aggregates (Lewy bodies). Motor symptoms appear only after roughly 60-80% of nigral dopaminergic neurons are lost, which is why the disease is already well established at diagnosis and why symptomatic therapy works: you are replacing a neurotransmitter the surviving circuit can still use.
Cardinal Motor Features
Bradykinesia -required for the diagnosis. Slowness with decrement in amplitude on repetitive movement (finger taps get smaller and slower). Smallness shows up as micrographia, hypomimia (masked face), hypophonia.
Rest tremor -4-6 Hz, classically pill-rolling, suppresses with action and re-emerges with distraction. Absent in up to 20-25%, so no tremor does not exclude PD.
Rigidity -lead-pipe resistance through the range, cogwheeling when tremor is superimposed. Asymmetric onset is typical of idiopathic PD.
Postural instability -a LATE feature. Early falls should make you question the diagnosis and think PSP.
Nonmotor Features (often precede motor by years)
Prodromal: constipation, anosmia, REM sleep behavior disorder (acting out dreams), depression. These reflect synuclein pathology starting outside the nigra (gut, olfactory bulb, brainstem).
Neuropsychiatric: depression and anxiety are common and treatable; psychosis is usually medication-related; dementia develops in a majority with long disease duration (if dementia starts within 1 year of motor symptoms, think dementia with Lewy bodies instead).
Red flags for atypical parkinsonism (not idiopathic PD): early falls (PSP), early severe autonomic failure (MSA), symmetric onset, poor or absent levodopa response, early dementia (DLB), vertical gaze palsy (PSP), cerebellar signs (MSA). Why it matters: atypical syndromes respond poorly to levodopa and progress faster, so the label changes both counseling and treatment expectations.
🧪 Workup
Diagnostic Workup
The diagnosis is clinical (MDS criteria: bradykinesia plus tremor or rigidity, with supportive features and no red flags). No lab or scan is required in a classic presentation.
Medication review FIRST -drug-induced parkinsonism from antipsychotics, metoclopramide (Reglan), or prochlorperazine (Compazine) is the reversible mimic you cannot afford to miss. It is typically symmetric and resolves over weeks to months after stopping the offender.
MRI brain -not to diagnose PD (usually normal) but to exclude structural mimics when the picture is atypical: vascular parkinsonism (lower-body predominant, stepwise), normal pressure hydrocephalus (gait apraxia + incontinence + cognitive change), midbrain atrophy of PSP.
DaTscan (ioflupane SPECT) -shows presynaptic dopaminergic degeneration. Useful ONLY when the question is "essential tremor or drug-induced parkinsonism vs a degenerative syndrome," because it is abnormal in PD, MSA, PSP, and DLB alike and therefore cannot distinguish among them. Do not order it to "confirm PD" in a classic case.
Levodopa response -a robust, sustained response supports idiopathic PD; a poor response at adequate doses (up to ~1,000 mg/day levodopa) is itself a red flag for an atypical syndrome.
Orthostatic vitals at diagnosis and at least annually -neurogenic orthostatic hypotension is common, frequently asymptomatic until it causes a fall, and aggravated by every dopaminergic drug you will prescribe. Measure supine then after 1 and 3 minutes standing.
🚨 Management
Starting and Escalating Therapy
Carbidopa-levodopa (Sinemet) is the most effective symptomatic therapy and first-line for most patients whose symptoms affect function. Typical start: 25/100 mg, half to one tablet TID, titrated to effect. Take 30-60 min before meals -dietary protein competes with levodopa for the intestinal and blood-brain large neutral amino acid transporter, so a protein-heavy meal can visibly blunt a dose.
Why carbidopa: it blocks peripheral dopa-decarboxylase, so more levodopa reaches the brain and less becomes dopamine in the periphery (the source of nausea and orthostasis). Patients need roughly 75 mg/day of carbidopa for adequate peripheral blockade.
Dopamine agonists (pramipexole (Mirapex), ropinirole (Requip), rotigotine (Neupro) patch) -an option in younger patients to delay levodopa motor complications. Avoid in the elderly and cognitively impaired: hallucinations, sedation and sudden sleep attacks, leg edema, and impulse control disorders (gambling, hypersexuality, compulsive shopping) -ask about these directly at every visit because patients rarely volunteer them.
MAO-B inhibitors (rasagiline (Azilect), selegiline, safinamide (Xadago)) -modest symptomatic benefit as early monotherapy or adjunct. Avoid meperidine and use caution with serotonergic drugs (serotonin syndrome risk).
Wearing-off between doses: shorten the dosing interval, or add entacapone (Comtan) 200 mg with each levodopa dose (COMT inhibition extends the levodopa half-life), an MAO-B inhibitor, or an agonist. Warn about harmless orange-brown urine with entacapone.
Dyskinesia (involuntary choreiform movements at peak dose):amantadine is the only medication with consistent antidyskinetic evidence. Reduce the dose in renal impairment (renally cleared); watch for confusion and hallucinations in the elderly and livedo reticularis.
Refractory fluctuations or tremor: refer for deep brain stimulation (STN or GPi) -best candidates are levodopa-responsive without dementia. Carbidopa-levodopa enteral gel (Duopa) is an alternative for severe fluctuations.
The Hospitalized PD Patient (where residents actually save lives)
Give levodopa ON TIME, on the patient's home schedule -not the ward's standard med-pass times. Late or missed doses cause rigidity, dysphagia, aspiration, falls, and panic; hospitalized PD patients have measurably worse outcomes when timing slips. Order it with explicit clock times.
NEVER stop dopaminergic therapy abruptly -abrupt withdrawal can precipitate parkinsonism-hyperpyrexia syndrome, an NMS-like emergency (high fever, severe rigidity, autonomic instability, elevated CK, altered consciousness) with real mortality. Treat by restarting the home regimen immediately (NG if needed), cooling, IV fluids; dantrolene or bromocriptine in severe cases.
NPO patient: levodopa via NG tube (tablets disperse in water), or convert to the rotigotine (Neupro) transdermal patch, or subcutaneous apomorphine with specialist input. "Hold all PO meds" is never the answer for levodopa.
NO dopamine blockers: haloperidol, risperidone, olanzapine, metoclopramide, and prochlorperazine all worsen parkinsonism and can trigger severe rigidity. For nausea use ondansetron (Zofran) or trimethobenzamide. For psychosis or agitation use quetiapine (Seroquel) low-dose or clozapine (the two antipsychotics with the least D2 blockade), or pimavanserin (Nuplazid), which is approved specifically for PD psychosis.
Dysphagia and aspiration: screen swallowing early, keep the patient upright for meals, involve speech pathology -aspiration pneumonia is a leading cause of death in PD.
Delirium precautions, early mobility, and fall precautions -check orthostatic vitals before first ambulation, because admission (bed rest, new antihypertensives, volume shifts) reliably worsens orthostatic hypotension.
The two inpatient traps: (1) held or delayed levodopa, and (2) a dopamine-blocking antiemetic or antipsychotic on the order set. Both are preventable, both are common, and both can end in an ICU transfer. Reconcile the home schedule at admission and flag the chart.
🩸 Orthostatic Hypotension
Neurogenic Orthostatic Hypotension (nOH) in PD
Definition: a sustained fall of ≥20 mmHg systolic or ≥10 mmHg diastolic within 3 minutes of standing. In PD it comes from degeneration of postganglionic sympathetic noradrenergic neurons (a baroreflex failure), aggravated by levodopa, dopamine agonists, and deconditioning. It affects 30-50% of patients, is often asymptomatic or presents atypically (fatigue, "brain fog," neck-and-shoulder "coat-hanger" ache), and is an independent predictor of falls, syncope, and cognitive impairment.
Bedside clue that it is neurogenic: the heart rate barely rises. A compensatory tachycardia (≥15-20 bpm) suggests volume depletion or blood loss; in neurogenic OH the baroreflex is broken, so ΔHR/ΔSBP < 0.5 bpm/mmHg points to a neurogenic cause. This one ratio separates "give fluids" from "treat the autonomic failure."
Step 1 - Remove the Aggravators
Deprescribe or move the offenders: alpha-blockers (tamsulosin, doxazosin), diuretics, tricyclics, and excess antihypertensives. In a patient with nOH plus supine hypertension, move needed BP agents to bedtime rather than morning -the goal is to treat the position, not the clock-time number.
Reassess the dopaminergic regimen: agonists cause more orthostasis than levodopa; sometimes the fix is trading agonist for levodopa rather than adding a pressor.
Step 2 - Nonpharmacologic (first-line, and genuinely effective)
Fluids 2-2.5 L/day and liberal salt 6-10 g/day -expands plasma volume, the substrate every other measure depends on. (Temper in HF or advanced CKD.)
Rapid water bolus: 16 oz (~500 mL) of water drunk quickly raises SBP within 5-15 minutes for about an hour (osmopressor response) -useful before getting out of bed or before a long stand.
Abdominal binder -compresses the splanchnic bed, where most of the orthostatic pooling actually happens, which is why a binder outperforms and out-complies thigh-high compression stockings. Put it on before standing, take it off when supine.
Head-up sleeping: raise the head of the bed 30-45 degrees -reduces nocturnal pressure natriuresis (so the patient wakes less volume-depleted and morning OH improves) and simultaneously blunts supine hypertension. One intervention treats both halves of the problem.
Physical counter-maneuvers -leg crossing, buttock clenching, squatting when presyncopal: skeletal muscle pumping buys the seconds needed to sit down safely.
Stand in stages (supine to sitting to standing with a pause at each), and prefer small, frequent, lower-carbohydrate meals if symptoms cluster after eating (postprandial splanchnic pooling).
Step 3 - Pharmacologic (when symptoms persist)
Midodrine (ProAmatine) 2.5-10 mg TID -alpha-1 agonist, constricts both venous capacitance and arterial resistance vessels. Last dose at least 4 hours before bedtime and no lying flat within 4 hours of a dose -it causes supine hypertension. Expect piloerection and scalp tingling (evidence it is working); watch urinary retention in men.
Droxidopa (Northera) 100-600 mg TID -oral norepinephrine prodrug, FDA-approved specifically for nOH. Same supine-hypertension caution: last dose 3-4 hours before bed, titrate every 24-48 h.
Fludrocortisone 0.1-0.2 mg daily -mineralocorticoid volume expansion. Watch potassium (it wastes K), edema, and supine hypertension; use cautiously in HF and the frail elderly for exactly those reasons.
Pyridostigmine (Mestinon) 30-60 mg TID -augments ganglionic transmission preferentially during standing (when sympathetic traffic is highest), so it improves standing BP with the LEAST supine hypertension. Modest effect; best for mild OH coexisting with bad supine hypertension.
The Supine Hypertension Trade-off
About half of nOH patients also have supine hypertension (≥140/90 lying flat), and every pressor you add makes it worse. Do not chase daytime numbers with standard antihypertensives -that recreates the falls problem you started with.
Manage positionally first: never lie fully flat, head-up sleeping, avoid daytime naps lying down. If supine BP is severe (≥160-180 systolic) despite that, a short-acting evening agent (losartan or a nitroglycerin patch applied at bedtime and removed on waking) treats the night without sabotaging the morning stand.
Monitoring: orthostatic vitals at 1 and 3 minutes at every visit, plus a home log of sitting and standing readings (morning and evening). Symptoms correlate poorly with numbers, so treat the patient, not just the drop.
💊 Medications
Medications
Drug
Role
Dose
Why / Watch For
Carbidopa-levodopa (Sinemet) FIRST-LINE
Motor symptoms
25/100 mg, 0.5-1 tab TID, titrate to effect
Most effective agent. Take 30-60 min before meals (protein competes for transport). NEVER stop abruptly (parkinsonism-hyperpyrexia). Nausea, orthostasis, dyskinesia with time.
Rotigotine (Neupro)
Agonist; NPO conversion
Patch 2-4 mg/24h start
The transdermal escape route when a PD patient is NPO. Impulse control disorders, sleep attacks, hallucinations in elderly.
Pramipexole (Mirapex)
Agonist (younger patients)
0.125 mg TID, slow titration
Delays levodopa complications; ask about gambling/compulsions at every visit. Renally cleared.
Rasagiline (Azilect)
MAO-B inhibitor
0.5-1 mg daily
Mild benefit, once daily. No meperidine (serotonin syndrome); caution with SSRIs.
Entacapone (Comtan)
Wearing-off
200 mg WITH each levodopa dose (max 8/day)
COMT inhibition extends each levodopa dose. Orange-brown urine is harmless; can amplify dyskinesia (reduce levodopa).
Amantadine
Dyskinesia
100 mg BID-TID
Only evidence-based antidyskinetic. Renally dose; confusion/hallucinations in elderly; livedo reticularis.
Quetiapine (Seroquel)
PD psychosis
12.5-25 mg qHS, titrate
Minimal D2 blockade, so it treats psychosis without freezing the patient. Clozapine has the best evidence but needs ANC monitoring. Pimavanserin (Nuplazid) 34 mg daily is the approved PD-psychosis agent.
Midodrine (ProAmatine) nOH
Orthostatic hypotension
2.5-10 mg TID
Alpha-1 pressor. Last dose ≥4h before bed; no lying flat after dosing (supine HTN). Scalp tingling = it is working.
Droxidopa (Northera) nOH
Neurogenic OH (FDA-approved)
100-600 mg TID, titrate q24-48h
Norepinephrine prodrug. Same supine-HTN discipline: last dose 3-4h before bed, head-up sleeping.
Fludrocortisone nOH
Volume expansion
0.1-0.2 mg daily
Works via salt/water retention, so it needs the salt+fluid base to work. Hypokalemia, edema, supine HTN; caution in HF.
Contraindicated in PD: haloperidol and other high-potency antipsychotics, metoclopramide (Reglan), prochlorperazine (Compazine) -all block D2 receptors and worsen parkinsonism. Meperidine with MAO-B inhibitors risks serotonin syndrome. Safe antiemetic: ondansetron.
🏥 Rounds
Pimp Questions
❓ Why can't you just hold levodopa in an NPO patient overnight?
Abrupt dopaminergic withdrawal can precipitate parkinsonism-hyperpyrexia syndrome: an NMS-like emergency with high fever, severe rigidity, autonomic instability, elevated CK, and altered consciousness, carrying real mortality. Even short of that, missed doses cause rigidity, dysphagia, and falls. Options: levodopa dispersed via NG tube, conversion to a rotigotine transdermal patch, or SC apomorphine. Restarting the home regimen IS the treatment if withdrawal syndrome develops.
❓ A PD patient is nauseated post-op. Which antiemetics are safe, and why are the usual ones dangerous?
Metoclopramide and prochlorperazine are dopamine D2 blockers that cross the blood-brain barrier, so they worsen parkinsonism and can cause severe rigidity. Use ondansetron (5-HT3 antagonist, no dopamine blockade) or trimethobenzamide. Same logic for agitation: haloperidol is contraindicated; quetiapine or clozapine have the least D2 blockade of the antipsychotics.
❓ How do you tell neurogenic orthostatic hypotension from volume depletion at the bedside?
Watch the heart rate response. In volume depletion the baroreflex is intact, so the HR rises briskly (≥15-20 bpm) as the BP falls. In neurogenic OH the baroreflex arc itself is degenerated, so the HR barely rises: a ΔHR/ΔSBP ratio below 0.5 bpm/mmHg suggests a neurogenic cause. This distinction changes the treatment from "give fluids and find the bleed" to "treat the autonomic failure."
❓ Why is an abdominal binder more effective than compression stockings for orthostatic hypotension?
Most orthostatic pooling happens in the splanchnic (mesenteric) circulation, not the legs -the splanchnic bed is a high-capacitance reservoir holding 20-30% of blood volume. An abdominal binder compresses exactly that reservoir, while thigh-high stockings compress a smaller venous bed and are much harder for a rigid, bradykinetic patient to put on, so real-world adherence is worse. Binder on before standing, off when supine.
❓ Why does raising the head of the bed 30-45 degrees improve MORNING orthostatic symptoms?
Lying flat all night, the nOH patient's supine hypertension drives nocturnal pressure natriuresis: the kidney sees high pressure and dumps salt and water, so the patient wakes 1-2 L volume-depleted, which is why the first stand of the morning is the worst of the day. Head-up sleeping lowers renal perfusion pressure overnight, cutting the natriuresis, and simultaneously treats the supine hypertension itself. One free intervention, both halves of the problem.
Sample Presentation
Mr. Alvarez is a 74-year-old man with 8 years of Parkinson disease on carbidopa-levodopa 25/100 two tabs at 6 AM, 11 AM, 4 PM, and 9 PM plus rasagiline, admitted with aspiration pneumonia. Overnight he was made NPO and his 6 AM levodopa was held; by rounds he is rigid, tremulous, and unable to swallow his secretions. Supine BP 148/86, standing 96/60 at 3 minutes with HR rising only from 72 to 78. He fell at home twice this month, "mostly in the mornings."
Key Points: (1) Restart levodopa NOW via NG (tablets disperse in water) on his home clock times, not ward times -his rigidity and worsened dysphagia are dose-delay effects and increase aspiration risk. (2) The blunted HR response (6 bpm for a 52 mmHg drop, ratio ~0.1) says neurogenic OH, not just sepsis-related volume depletion -fluids alone will not fix it. Start conservative measures (head-up bed, binder before ambulation, water bolus before standing), review his tamsulosin, and consider midodrine while inpatient with no doses within 4h of lying down. (3) Flag the chart: no metoclopramide, no haloperidol; ondansetron and quetiapine are the safe substitutes.
Daily Rounds Checklist
Levodopa timing -were all doses given within 30 min of home schedule? Reconcile daily; this is the highest-yield checkbox on the list.
Med list scan -any dopamine blocker (metoclopramide, prochlorperazine, haloperidol) added overnight? Remove it and document why.
Orthostatic vitals before ambulation -supine, 1 min, 3 min standing with HR. Falls in hospital usually happen on the way to the bathroom.
Swallow status -any coughing with meals, wet voice, or worsening "off" time? Re-screen and involve SLP early; aspiration is the killer complication.
Bowel regimen -constipation is near-universal, worsens levodopa absorption (delayed gastric emptying), and precipitates delirium. Scheduled, not PRN.
Delirium check and sleep -reorient, minimize overnight vitals if stable, avoid anticholinergics and benzodiazepines (both worsen cognition and falls).
Disposition planning -PT/OT early; a PD patient deconditioned by a week in bed loses ground that takes months to regain.
📋 Summary
Summary
Make the Diagnosis Clinically
Bradykinesia plus rest tremor or rigidity, asymmetric onset, robust levodopa response. Order MRI only for atypical features and DaTscan only to separate degenerative parkinsonism from essential tremor or drug-induced disease, because DaTscan cannot tell PD from MSA, PSP, or DLB. Always review the med list first: metoclopramide and antipsychotic parkinsonism is the reversible mimic.
Levodopa Is the Workhorse
Carbidopa-levodopa 25/100, half to one tab TID, taken 30-60 min before meals because dietary protein competes for the transporter that carries levodopa into blood and brain. Titrate to function, not to a number. Poor response at adequate doses is a red flag for atypical parkinsonism, not a reason to abandon the diagnosis quietly.
Match the Drug to the Patient
Agonists in the young (delay motor complications), levodopa in the old (fewer psychiatric side effects). Ask every agonist patient about gambling, shopping, and hypersexuality, because impulse control disorders are common, hidden, and reversible on withdrawal. Amantadine is the one drug that treats dyskinesia; entacapone extends each levodopa dose when wearing-off appears.
In Hospital, Timing Is the Treatment
Home schedule, exact clock times, never abruptly stopped. Withdrawal can cause parkinsonism-hyperpyrexia syndrome, an NMS-like emergency treated by restarting the drug. NPO means NG levodopa or a rotigotine patch, never "hold." The order set traps are metoclopramide, prochlorperazine, and haloperidol; the safe substitutes are ondansetron and quetiapine.
Look for the Falls Nobody Explains
Orthostatic hypotension affects a third to a half of PD patients and is often silent -fatigue, fog, and a coat-hanger ache are its disguises. Check supine and 1- and 3-minute standing vitals at every visit. A blunted heart rate response (ΔHR/ΔSBP < 0.5) says neurogenic, which means fluids alone will not fix it.
Treat nOH From the Bottom of the Pyramid Up
First remove aggravators (alpha-blockers, diuretics, TCAs), then salt 6-10 g, fluids 2-2.5 L, water boluses, abdominal binder, head-up sleeping at 30-45 degrees. These work through volume and the splanchnic reservoir, which is where the blood actually pools. Only then add midodrine or droxidopa, with no doses within 4 hours of lying down.
Respect the Supine Hypertension Trade-off
Half of nOH patients are hypertensive lying down, and every pressor worsens it. Treat positionally (head-up sleeping, no flat naps) and, if severe, with a short-acting agent at bedtime only, because a morning antihypertensive recreates the falls you were trying to prevent. Treat the position, not the number.
The Nonmotor Disease Is the Disease
Constipation, REM sleep behavior disorder, depression, psychosis, dementia, and autonomic failure drive quality of life and mortality more than tremor does. Scheduled bowel regimen (constipation also blunts levodopa absorption), screen mood, treat psychosis with quetiapine, clozapine, or pimavanserin, and remember aspiration pneumonia is a leading cause of death -swallow surveillance is not optional.
The first guideline of its kind, published in JACC on June 9, 2026. It retires and replaces the 2013 AHA/ACC/TOS obesity guideline. The central argument: obesity, type 2 diabetes, chronic kidney disease and cardiovascular disease are not four separate problems managed in four separate clinics, they are one interconnected syndrome, and staging it changes what you screen for and when. CKM stages 0 to 4NEW: Stage 0 normal weight, glucose, BP, lipids and kidney function with no CVD. Stage 1 excess or dysfunctional adipose tissue, prediabetes. Stage 2 metabolic risk factors (hypertriglyceridemia, hypertension, metabolic syndrome, T2D) or moderate-to-high-risk CKD. Stage 3 subclinical CVD with CKM risk factors, or high predicted 10-year CVD risk (≥ 20%). Stage 4 clinical CVD (coronary disease, heart failure, stroke, PAD, atrial fibrillation) with CKM risk factors. Screening cadence is set by stage, which is the practical change for clinic: anthropometrics and blood pressure annually in everyone; lipids, glucose and eGFR every 5 years in Stage 0, every 2 to 3 years in Stage 1, annually in Stage 2; and urine albumin-to-creatinine ratio annually from Stage 2 onward. Risk tool: the PREVENT equations, the same family adopted by the 2026 dyslipidemia guideline, so one calculator now serves both. Drug therapy by problem:GLP-1 receptor agonists (semaglutide, tirzepatide) for obesity, with bariatric surgery considered in Stages 1 to 3. SGLT2 inhibitors as foundational therapy in T2D. Semaglutide specifically for kidney protection when albuminuria is present. RAS inhibitors for everyone with albuminuria, and a nonsteroidal mineralocorticoid receptor antagonist (finerenone) for persistent albuminuria despite that. Honest caveat the guideline itself makes: at current GLP-1 pricing the cost-effectiveness analysis does not support broad use for cardiovascular prevention, though lower prices would. Care is tiered by comorbidity burden, from lifestyle alone up to multidisciplinary teams with a CKM coordinator.
2026 AHA/ACC Guideline for Acute Pulmonary Embolism
The first ever AHA/ACC guideline dedicated to acute PE, published in Circulation on March 24, 2026 (epub February 19), written across 11 organizations including ACCP, ACEP, CHEST, SCAI, SHM, SIR, SVM and SVN. The big change is the vocabulary: the old massive / submassive / low-risk language is replaced by the AHA/ACC Acute PE Clinical Categories, A through E with subcategoriesNEW, graded from low to high risk of adverse outcome. The point is that "submassive" lumped together patients whose management now diverges sharply. Disposition follows the category.Category A (asymptomatic PE) can go home from the emergency department and does not need admission. Category C (symptomatic with an elevated severity score, elevated biomarkers and/or RV dysfunction), Category D (incipient cardiopulmonary failure) and Category E (cardiopulmonary failure with persistent hypotension) should be hospitalized. Advanced therapy thresholds: systemic thrombolysis, catheter-directed thrombolysis, mechanical thrombectomy and surgical embolectomy are reasonable in Category E1 and may be considered in Categories D1 to D2. PE response teams (PERT) are recommended to improve the timeliness of these decisions, which is the part most likely to change how your hospital is organized rather than what you personally prescribe.
First major update since 2018. Released March 13, 2026 by ACC/AHA in conjunction with AACVPR/ABC/ACPM/ADA/AGS/APhA/ASPC/NLA/PCNA. Retitled from "Blood Cholesterol" to "Dyslipidemia" to reflect broader scope (LDL + TG + remnants + Lp(a)). Core principle: "lower LDL for longer is better" -cumulative-exposure framing analogous to pack-years. Risk calculator:PREVENT-ASCVD replaces the 2013 Pooled Cohort Equation. Validated ages 30-79, removes race as input, adds CKD/HbA1c/social deprivation, estimates 10- AND 30-year risk. Generally produces lower 10-yr estimates than PCE -especially in Black patients and the elderly. New risk categories: Low <3% / Borderline 3-<5% / Intermediate 5-<10% / High ≥10% (replaces 2018's <5/5-7.5/7.5-20/≥20%). Lower LDL targets in primary preventionNEW: PREVENT ≥10% → LDL <70. PREVENT 5-<10% → LDL <100. 2018 had no numeric primary-prev LDL goal -only "≥50% reduction." Earlier statin starts: all HeFH at diagnosis (incl. children 8-10), age ≤30 with LDL ≥160, strong family hx of premature ASCVD, high 30-yr PREVENT risk. New "early intervention" category formalizes treating young high-LDL patients before age 40. Routine apoB and Lp(a) testing: Lp(a) once per lifetime in all adults. ApoB when LDL goal met, especially TG ≥150, DM, or LDL <70. Goal apoB <55 in very-high-risk ASCVD. Non-statin add-ons: reframed from strict ladder to parallel options (ezetimibe / bempedoic acid / PCSK9i mAb / inclisiran). Combination therapy is the rule, not the exception, for very-high-risk ASCVD. CLEAR Outcomes 2023 (bempedoic acid) and ORION (inclisiran) data drove this expansion. HIV (REPRIEVE 2023): pitavastatin 4 mg cut MACE 35% in HIV patients age 40-75 below traditional LDL threshold -statin recommended for primary prevention in HIV regardless of LDL.
First major update since 2021. Published March 23, 2026 by SCCM/ESICM. 129 statements including 46 entirely new recommendations. Key changes: Screening:NEWS/NEWS2/MEWS/SIRS now recommended over qSOFA for sepsis screening. qSOFA has poor sensitivity and should not be used as a sole screening tool. Sepsis remains a clinical diagnosis -no single biomarker can rule it in or out. Fluids: Balanced crystalloids suggested over 0.9% saline. Initial bolus of at least 30 mL/kg IV crystalloid in first 3 hours for sepsis-induced hypoperfusion. Albumin not recommended as supplement to crystalloids. New guidance on fluid removal after resuscitation -a topic not previously addressed. Vasopressors:Peripheral vasopressors OK to start -don't delay for central access. Norepinephrine remains first-line (downgraded from strong to conditional recommendation), then vasopressin, then epinephrine. MAP target ≥ 65 mmHg; new: MAP 60-65 for adults ≥ 65 years. Prolonged beta-lactam infusion now recommended (strong) for maintenance dosing. Corticosteroids: IV hydrocortisone 200 mg/day suggested for septic shock with ongoing vasopressor requirement (maintained from 2021, which reversed the 2016 stance against routine steroids). Shortens shock duration but unclear mortality benefit. Trial enrollment (ADRENAL, APROCCHSS) used a ≥ 4h threshold, but no specific wait time is mandated. Antibiotics: Broad-spectrum within 1 hour for septic shock, within 3 hours for sepsis without shock. Blood cultures before antibiotics when possible. New section on antibiotic optimization beyond just timing. New topics: "Code sepsis" / sepsis huddle protocols suggested. Performance improvement programs recommended at institutional level. Post-sepsis discharge care including psychological and physical rehabilitation. Prehospital antibiotics may reduce mortality (OR 0.58, very low certainty). Pediatric: 68-expert panel, 20 new topics. POCUS conditionally recommended to guide resuscitation. 30–40% of children surviving ICU-level sepsis face lasting health issues -long-term follow-up now addressed.
Annual update covering all aspects of diabetes care. Key 2026 changes: GLP-1 RA / dual GIP-GLP-1 (tirzepatide, semaglutide) elevated to first-line for obesity-related T2DM ahead of sulfonylureas / TZDs, especially when weight management is a goal. SGLT2 inhibitors recommended for ALL patients with CKD (eGFR ≥ 20, regardless of A1c) -mirrors KDIGO 2024. Continuous glucose monitoring (CGM) expanded to T2DM on any basal insulin (previously intensive insulin only). Time-in-range targets formalized. DM screening starts at age 35 for all adults regardless of risk; age 25 if BMI ≥ 25 + risk factors (down from 35 with BMI criterion). Inpatient targets: glucose 140-180 mg/dL most patients; basal-bolus preferred over sliding-scale-only; SQ insulin acceptable for mild-moderate DKA. Lp(a) screening once per lifetime in adults with DM (mirrors ACC/AHA 2026 Dyslipidemia Guideline). GLP-1 RA + SGLT2i preferred over insulin in many T2DM scenarios when ASCVD, HF, or CKD coexist -insulin is not "default escalation" anymore.
Annual update from the Global Initiative for Chronic Obstructive Lung Disease. Key 2026 refinements: biologics codified for severe eosinophilic COPD -mepolizumab, benralizumab (anti-IL-5/IL-5R), and dupilumab (anti-IL-4Rα) for patients with frequent exacerbations and blood eosinophils ≥ 300 cells/μL despite optimized inhaler triple therapy. ABE classification (introduced 2023, refined further) -A (low symptom, low exacerbation risk), B (high symptom, low exacerbation), E (any exacerbations regardless of symptom). Old ABCD framework retired. Inhaled triple therapy (LABA/LAMA/ICS) reserved for Group E with eos ≥ 300 OR persistent exacerbations on LABA/LAMA. ICS-without-LABA is not appropriate. Step-down to LABA/LAMA encouraged when eos low and stable. Spirometry severity (GOLD 1-4) retained for FEV1 % predicted; symptoms (CAT, mMRC) and exacerbation history drive treatment, not GOLD stage alone. Smoking cessation pharmacotherapy escalated -varenicline preferred, cytisinicline now available (newer agent), combination NRT (patch + short-acting) emphasized over patch alone. Pulmonary rehab strongly emphasized post-exacerbation (within 4 weeks) -reduces 1-year mortality and rehospitalization.
First unified ACS guideline replacing the 2013 STEMI and 2014 NSTE-ACS guidelines. Biggest practice change: 1 month DAPT followed by ticagrelor monotherapy is now Class 1, LOE A (TWILIGHT, TICO, T-PASS), cuts major bleeding ~44% without raising ischemic risk. Ticagrelor or prasugrel preferred over clopidogrel post-PCI (clopidogrel is the preferred dual-therapy partner only when stacked on top of an OAC). For AFib + ACS + PCI: short triple therapy (1 to 4 weeks), then drop ASA, then OAC + clopidogrel through month 12 (Class 1; AUGUSTUS). LDL targets pushed lower: non-statin add-on if LDL ≥ 70 (Class 1), reasonable to intensify if LDL 55 to <70 (Class 2a). Intravascular imaging upgraded to Class 1 for PCI guidance. Complete revascularization Class 1 in multivessel disease (COMPLETE, MULTISTARS-AMI). Microaxial flow pump (Impella CP) Class 2a in select AMI cardiogenic shock per DanGer Shock 2024 (first positive shock RCT, 180-day mortality 45.8% vs 58.5%). Radial access preferred over femoral (Class 1; MATRIX). 0/1h and 0/2h hs-troponin algorithms formalized. → Full 2025 ACS Changes Comparison • → STEMI Topic • → NSTEMI Topic • → Read Full Guideline (Circulation)
2025
KDIGO 2024 CKD Guidelines Updated
Updated GFR categories and albuminuria staging. SGLT2 inhibitors now first-line for CKD with albuminuria regardless of diabetes status. Finerenone added for diabetic kidney disease. → CKD Topic
2025
2025 AHA/ACC Hypertension Guidelines
First major update since 2017. Replaces the prior hypertension guideline with updated evidence through 2025. Key changes include earlier risk stratification, expanded screening for secondary causes including primary aldosteronism, updated lifestyle and psychosocial intervention recommendations, and more individualized BP targets across the lifespan. Addresses tailored strategies for older adults, CKD, and resistant hypertension. → HTN Emergency Topic
2025
IDSA 2025: First Complicated UTI Guidelines
First-ever IDSA guidelines for complicated UTIs. Provides a clinically relevant classification system for cUTI, stepwise approach to empiric antibiotic selection based on local resistance patterns, guidance on IV-to-oral antibiotic switch timing, and evidence-based duration of therapy. Addresses catheter-associated UTI, pyelonephritis with complicating factors, and urosepsis. → UTI Topic
2025
ATS CAP Guidelines Update — IDSA Declines to Endorse
ATS released updated community-acquired pneumonia guidelines. IDSA agreed with 8 of 10 recommendations but declined endorsement over antibiotic use in viral pneumonia. IDSA argues that nondiscriminatory antibiotic use in patients with positive respiratory virus tests (flu, RSV, COVID) confers more harm than benefit, since most do not have bacterial coinfection. Practice impact: think twice before reflexively adding antibiotics to confirmed viral CAP. → Pneumonia Topic
2024
2024 NLA Scientific Statement on Lp(a)
National Lipid Association moved Lp(a) from "consider checking in selected patients" to routine once-per-lifetime measurement in all adults. Lp(a) ≥50 mg/dL (or ≥125 nmol/L) is a major risk enhancer; Lp(a) ≥50 + established ASCVD = "very-high-risk" classification driving LDL goal <55. Statins don't lower Lp(a); PCSK9i and inclisiran lower it ~20-25%. Apheresis for refractory. Set the stage for the 2026 ACC/AHA Dyslipidemia Guideline adoption of routine Lp(a) testing. → Outpatient Lipid Management Topic
2024
NCCN irAE Guidelines Updated
Updated management of immune-related adverse events from checkpoint inhibitors. Expanded guidance on steroid dosing, when to hold immunotherapy, and specialty referral triggers. → irAE Topic
2024
SURMOUNT-OSA: Tirzepatide for Sleep Apnea
Tirzepatide (Mounjaro) significantly reduced AHI in obese patients with OSA. Weight loss of ~20% with improvement in sleep apnea severity. May change first-line management of obesity-related OSA. → Obesity Topic
Replaced the 2012 Stable Ischemic Heart Disease guideline. New "Chronic Coronary Disease" (CCD) framework consolidates stable angina, post-MI/post-revasc, asymptomatic plaque, and silent ischemia into one umbrella. Key changes: SGLT2i and GLP-1 RA codified for ASCVD patients with DM (diabetes-class effect on MACE). ISCHEMIA trial integrated -no benefit of routine revascularization in stable CCD with moderate ischemia; med therapy first. Icosapent ethyl (REDUCE-IT) recommended for residual TG-driven ASCVD risk in patients with TG 150-499 on statin. DAPT duration after PCI individualized by bleeding/ischemic risk balance. Lifestyle reinforcement, depression screening, and structured cardiac rehab strongly recommended. → Stable Angina / CCD Topic
2023
CLOVERS Trial: Restrictive vs Liberal Fluids in Sepsis
No difference between restrictive and liberal fluid strategies in early septic shock. Supports individualized fluid resuscitation over mandatory 30 mL/kg. → Sepsis Topic
Semaglutide reduced MACE by 20% in overweight/obese adults with CVD, regardless of diabetes status. First GLP-1 RA with cardiovascular benefit independent of diabetes. → Obesity Topic
2023
STEP-HFpEF: Semaglutide in HFpEF with Obesity
Semaglutide improved symptoms, exercise function, and reduced body weight in obese HFpEF patients. New treatment paradigm -treating the obesity driving HFpEF. → HFpEF Topic
2022
STRONG-HF: Rapid GDMT Initiation Before Discharge
Rapid uptitration of all 4 GDMT pillars before discharge improved 180-day outcomes. Changed practice from slow sequential titration to rapid parallel initiation. → Heart Failure Topic
2022
WATERFALL Trial: No Aggressive Fluids in Pancreatitis
Aggressive LR resuscitation did not improve outcomes in acute pancreatitis and increased fluid overload. Goal-directed fluid therapy is now preferred. → Pancreatitis Topic
2022
DELIVER Trial: Dapagliflozin for HFpEF
SGLT2 inhibitors now benefit ALL heart failure regardless of ejection fraction. Dapagliflozin reduced worsening HF and cardiovascular death in HFpEF. → HFpEF Topic
2022
EMPA-KIDNEY: Empagliflozin for CKD
Empagliflozin reduced CKD progression and cardiovascular death regardless of diabetes status. SGLT2i now standard for CKD with albuminuria. → CKD Topic
⚡ Major Paradigm Shifts (2019–2021)
2021
SSC 2021: Surviving Sepsis Campaign Updated
30 mL/kg fluid bolus downgraded to weak recommendation. Balanced crystalloids suggested over NS. Hour-1 bundle replaces 3-hour and 6-hour bundles. Norepinephrine confirmed first-line vasopressor. → Sepsis Topic
2021
TTM2: Hypothermia After Cardiac Arrest Debunked
33°C hypothermia showed no benefit over normothermia (36°C) after cardiac arrest. Aggressive fever prevention is what matters, not active cooling. Changed post-arrest temperature management. → Post-Cardiac Arrest Topic
2021
IDSA/SHEA 2021: C. difficile -Fidaxomicin First-Line
Fidaxomicin (Dificid) now preferred over oral vancomycin for initial C. diff episodes -lower recurrence rate. Oral metronidazole is NO LONGER recommended for initial episodes. → C. difficile Topic
2020
Vancomycin AUC-Based Dosing (ASHP/IDSA 2020)
Trough-based monitoring (target 15-20 mcg/mL) replaced by AUC/MIC-guided dosing (target 400-600). AUC monitoring reduces nephrotoxicity by ~30% with equivalent efficacy. → Sepsis Topic
2020
EAST-AFNET 4: Early Rhythm Control in AF
Early rhythm control (within 1 year of AF diagnosis) reduced cardiovascular death, stroke, and HF hospitalization vs rate control alone. Shifted the rate vs rhythm debate for newly diagnosed AF. → Atrial Fibrillation Topic
2020
STARRT-AKI & AKIKI: Don't Rush to Dialysis
Early RRT initiation in AKI showed no benefit over a watchful waiting strategy. Delayed approach avoided unnecessary dialysis in ~50% of patients. Only start for absolute indications. → AKI Topic
2019
ATS/IDSA 2019: HCAP Eliminated
Healthcare-Associated Pneumonia (HCAP) removed as a category. Led to massive overtreatment with unnecessarily broad antibiotics. Instead, assess individual MDR risk factors and use nasal MRSA PCR to guide de-escalation. → Pneumonia Topic
2019
OVIVA Trial: Oral Antibiotics for Bone Infections
Oral antibiotics non-inferior to IV for bone and joint infections after initial IV therapy. Changed the dogma of "6 weeks IV only" for osteomyelitis. IV-to-oral step-down is now standard practice. → Osteomyelitis Topic
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ICUCritical2026 Update
Surviving Sepsis Campaign 2026 Guidelines
First major update since 2021. Published March 23, 2026 by SCCM/ESICM. 129 statements including 46 entirely new recommendations. Here's everything that changed and why it matters for your practice.
⚖️ Surviving Sepsis Campaign 2021 vs 2026 Side-by-Side
NEWS/NEWS2/MEWS/SIRS now recommended OVER qSOFA. qSOFA has poor sensitivity -misses too many septic patients. Should not be sole screening tool. Sepsis remains a clinical diagnosis.
Major
Fluid Type
Crystalloids recommended. No clear preference between balanced crystalloids and normal saline.
Balanced crystalloids (LR/PlasmaLyte) now suggested over 0.9% saline. Exception: TBI patients -use NS (risk of cerebral edema with hypotonic solutions).
Major
Fluid Volume
30 mL/kg crystalloid within 3 hours for sepsis-induced hypoperfusion. Conditional recommendation.
30 mL/kg still suggested (conditional, unchanged strength). Greater focus on individualization and dynamic reassessment after each bolus. New: after initial 30 mL/kg with persistent hypoperfusion, suggest either liberal or restrictive strategy based on individual factors. Supported by CLOVERS, 2023: no difference between restrictive (~1.8L) and liberal (~3.8L).
Moderate
Fluid Removal
Not addressed.
New: fluid removal (de-resuscitation) after stabilization now addressed. Fluid overload harms -actively manage it once resuscitation is complete.
New
Vasopressor Access
Start vasopressors via central venous catheter.
Peripheral vasopressor start now acceptable. Don't delay pressors waiting for central line placement. Start NE peripherally, establish central access in parallel.
Major
Vasopressor Choice
Norepinephrine first-line (strong recommendation). Vasopressin or epinephrine as second-line. Against dopamine as alternative.
NE first-line remains a strong "recommend" over dopamine, epinephrine and selepressin. Separately, NE over vasopressin or angiotensin II is a conditional "suggest" - that narrower statement is what is sometimes misread as a blanket downgrade. NE → vasopressin → epinephrine order unchanged. Dopamine remains discouraged. Against angiotensin II, terlipressin, or selepressin.
Moderate
MAP Target
MAP ≥ 65 mmHg. Higher targets (80+) showed no benefit.
MAP ≥ 65 mmHg unchanged for general population. New: for adults ≥ 65 years, suggest initial MAP 60-65 mmHg over higher targets. Spares vasopressor exposure without increasing mortality.
Major
Corticosteroids
Suggested if ongoing vasopressor requirement. (This was the 2021 reversal of the 2016 recommendation against routine steroids.)
Maintained from 2021. Hydrocortisone 200 mg/day (50 mg q6h) for septic shock with ongoing vasopressor requirement. Shortens shock duration. ADRENAL 2018 + APROCCHSS 2018 enrolled patients on pressors ≥ 4h, but no specific wait time is mandated.
Maintained
Antibiotic Timing
Broad-spectrum antibiotics within 1 hour of sepsis recognition for ALL patients.
Now tiered: 1 hour for septic shock, 3 hours for sepsis without shock. Recognizes that not all sepsis requires the same urgency. Blood cultures before antibiotics when possible.
Major
Antibiotic Optimization
Focus on early administration. De-escalation at 48-72h.
New section on antibiotic optimization beyond timing. Stewardship emphasized. De-escalation reinforced. Prehospital antibiotics may reduce mortality (OR 0.58, very low certainty).
New
Anti-Anaerobic Coverage
Not specifically addressed.
New: Avoid anti-anaerobic antibiotics (e.g., metronidazole, pip-tazo anaerobic component) in patients at LOW risk for anaerobic infection. Risk factors for anaerobic infection: intra-abdominal source, deep gynecologic/obstetric infection, necrotizing soft tissue, head & neck, CNS abscess. Most lung and UTI sources are aerobic, don't reflexively add anaerobic coverage.
New
Beta-Lactam Infusion
Not specifically addressed.
New: recommend (strong) prolonged infusion of beta-lactams for maintenance dosing (after initial loading dose) over bolus administration. Moderate certainty evidence. Sustained drug levels improve time-dependent killing and reduce mortality.
New
Fluid Responsiveness
Not specifically addressed.
New: suggest using dynamic measures (passive leg raise, stroke volume variation, pulse pressure variation) over physical exam or static measures alone to guide initial fluid resuscitation.
New
Blood Purification
Suggested against PMMA hemoperfusion. Insufficient evidence for other modalities.
Suggest against blood purification therapies including hemoperfusion, high-dose hemofiltration, and plasma exchange for sepsis/septic shock.
Moderate
Lactate
Measure lactate. Remeasure if initial > 2 mmol/L. Guide resuscitation to normalize lactate.
Reframed. Serial lactate still recommended, but do NOT use elevated lactate as reflexive indication for more fluids. Lactate elevation is multifactorial, only a small percentage is from hypovolemic hypoperfusion. Individualize fluid therapy after initial bolus based on dynamic measures, not lactate normalization alone.
Moderate
Albumin
Suggested as supplement to crystalloids for patients receiving large volumes.
Reversed: now suggests crystalloids alone over crystalloids + albumin for initial resuscitation. Exception: albumin may be appropriate after large crystalloid volumes or in cirrhosis. Avoid in TBI.
Major
Code Sepsis
Not addressed.
New: "Code sepsis" huddle protocols suggested. Structured multidisciplinary response to sepsis recognition, similar to code blue or stroke codes.
New: post-sepsis discharge care now addressed. Psychological rehabilitation (PTSD, depression, anxiety). Physical rehabilitation. Long-term follow-up. Sepsis survivors face increased mortality for years after discharge.
New
Pediatric
Separate pediatric guidelines with 77 recommendations.
Updated: 68-expert panel, 20 new topics. POCUS conditionally recommended for resuscitation guidance. 30-40% of children surviving ICU-level sepsis face lasting health issues -long-term follow-up now addressed.
Major
🔥 Key Changes at a Glance
Bottom Line: The 2026 SSC guidelines shift sepsis care toward earlier, more individualized management -balanced crystalloids over NS, peripheral vasopressors OK, steroids suggested for refractory shock, antibiotics tiered by severity (1h shock / 3h no shock), and NEWS/MEWS replaces qSOFA for screening. The days of rigid protocolized bundles are evolving toward dynamic, patient-centered resuscitation.
🚨 The 7 Biggest Changes
1. Screening Overhaul
NEWS/MEWS/SIRS now recommended OVER qSOFA. qSOFA missed too many septic patients (poor sensitivity). Sepsis remains a clinical diagnosis -no single biomarker rules it in or out.
2. Balanced Crystalloids Preferred
LR/PlasmaLyte suggested over 0.9% saline (except TBI -use NS). 30 mL/kg still suggested but with greater emphasis on individualization. New: fluid removal after resuscitation now addressed.
3. Peripheral Vasopressors OK
Don't delay vasopressors for central access. Start NE peripherally while central line is placed. NE still first-line but downgraded from strong to conditional recommendation. NE → vasopressin → epi order unchanged. New: MAP 60-65 for adults ≥ 65 years.
4. Prolonged Beta-Lactam Infusion
Recommend (strong) prolonged infusion of beta-lactams for maintenance dosing after an initial loading dose, over traditional bolus administration. Sustained drug concentrations above MIC improve time-dependent killing and reduce mortality. Give a loading dose first.
5. Tiered Antibiotic Timing
1 hour for septic shock. 3 hours for sepsis without shock. Previously 1h for all. Blood cultures before antibiotics when possible. New section on antibiotic optimization beyond just timing.
6. Code Sepsis & Post-Discharge
"Code sepsis" huddle protocols suggested. Institutional performance improvement programs recommended. Post-sepsis discharge care including psychological and physical rehabilitation now addressed.
7. Anti-Anaerobic Stewardship
Avoid anti-anaerobic antibiotics in low-risk patients. Most sepsis from lung/UTI sources is aerobic. Reserve anaerobic coverage for intra-abdominal, necrotizing soft tissue, and deep pelvic sources. A major antibiotic stewardship win.
The 2026 guidelines include 46 entirely new recommendations not present in any prior SSC document. Here are the most practice-relevant new topics:
🚨 Code Sepsis Protocols
Structured "code sepsis" huddle protocols are suggested at the institutional level. Similar to code blue, stroke alert, or STEMI activation. Multidisciplinary team response with defined roles, time targets, and communication structure. Goal: reduce time to antibiotics and vasopressors through standardized recognition and response.
💊 Prehospital Antibiotics
EMS-administered antibiotics may reduce sepsis mortality (OR 0.58). Evidence is very low certainty but the signal is strong enough to warrant discussion. Could change EMS protocols to include empiric antibiotics for suspected sepsis in the field, similar to aspirin for chest pain.
🩺 Post-Sepsis Rehabilitation
Sepsis survivors face increased mortality for years after discharge. Post-sepsis syndrome includes: cognitive impairment, PTSD, depression, anxiety, chronic pain, and functional decline. Psychological and physical rehabilitation now formally recommended. Discharge planning should include sepsis-specific follow-up.
📉 Fluid Removal (De-Resuscitation)
For the first time, SSC addresses fluid removal after initial resuscitation. Fluid overload is independently associated with worse outcomes (pulmonary edema, abdominal compartment syndrome, AKI). Active de-resuscitation with diuretics once hemodynamically stable is now part of the guideline framework.
🧪 Lactate Reframing
Elevated lactate should NOT trigger reflexive fluid administration. Only a small percentage of sepsis-related lactate elevation is from hypovolemic hypoperfusion. Causes are multifactorial (stress response, mitochondrial dysfunction, hepatic clearance). Individualize fluid therapy using dynamic measures (PLR, stroke volume variation, capillary refill time) rather than chasing lactate normalization.
🧓 Older Adult BP Targets
For adults ≥ 65 years with septic shock, SSC 2026 suggests an initial MAP target of 60-65 mmHg over higher targets. Previous guidelines used a one-size-fits-all MAP ≥ 65 mmHg. Lower targets in older adults spare vasopressor exposure and reduce complications without increasing mortality.
🏥 Institutional QI Programs
Performance improvement programs at the institutional level are now formally recommended. Includes sepsis education, bundle compliance monitoring, feedback loops to clinical teams, and outcome tracking. Data-driven quality improvement shown to reduce sepsis mortality.
💉 Prolonged Beta-Lactam Infusion
Recommend (strong, moderate certainty) prolonged infusion of beta-lactams for maintenance dosing after an initial loading dose, over traditional bolus administration. Sustained drug concentrations above MIC improve time-dependent bacterial killing and reduce mortality. Give a loading dose first to avoid delayed therapeutic levels.
📈 Dynamic Fluid Assessment
Suggest using dynamic measures (passive leg raise, stroke volume variation, pulse pressure variation, IVC ultrasound) over physical exam or static measures alone to guide initial fluid resuscitation. Static exam findings (skin turgor, JVP) are unreliable predictors of fluid responsiveness in sepsis.
🚫 Blood Purification Not Recommended
Suggest against blood purification therapies including hemoperfusion, high-dose hemofiltration, and plasma exchange for sepsis and septic shock. Despite theoretical appeal of cytokine removal, evidence does not support clinical benefit.
Pediatric Highlights
68-expert panel with 20 new topics. POCUS is now conditionally recommended to guide fluid resuscitation in pediatric sepsis. 30-40% of children surviving ICU-level sepsis face lasting health issues including cognitive, psychological, and physical sequelae. Long-term follow-up and rehabilitation are now formally addressed in the pediatric guidelines.
Key Trials Supporting 2026 Changes
Trial
Year
Finding
2026 Impact
SMART
2018
Balanced crystalloids reduced MAKE-30 vs NS in ICU patients
Supports balanced crystalloids over NS
CLOVERS
2023
No difference between restrictive (~1.8L) and liberal (~3.8L) fluids in early septic shock
Supports individualized fluid resuscitation
SOAP II
2010
No difference in 28-day mortality (48.5% NE vs 52.5% dopamine, p = 0.10); dopamine caused twice the arrhythmias (24.1% vs 12.4%, p < 0.001), with excess mortality confined to the cardiogenic shock subgroup
NE remains first-line vasopressor, on the arrhythmia safety signal rather than a survival benefit
VASST
2008
Adding low-dose vasopressin to NE spared catecholamines
Vasopressin remains second-line add-on
ADRENAL
2018
Hydrocortisone: faster shock resolution, no mortality benefit
Supports early steroids for shock duration
APROCCHSS
2018
Hydrocortisone + fludrocortisone reduced 90-day mortality in septic shock
Strengthens steroid recommendation
CORTICUS
2008
Hydrocortisone hastened shock reversal but no survival benefit
RoundsRx Infographic Series · #1 · Sepsis & Infection · PDF 155 KB
High-YieldICU / Wards🆕 2025 Update
ICU Sedation, Delirium & Sleep
The 2025 SCCM Focused Update to the PADIS (Pain, Anxiety, Agitation/Sedation, Delirium, Immobility, Sleep) Guidelines updates the landmark 2018 guidelines with new evidence on sedation selection, melatonin, enhanced mobilization, and anxiety management. Bottom line: dexmedetomidine over propofol when targeting light sedation, melatonin for sleep, and enhanced mobilization/rehabilitation are now formally recommended.
🔍 Overview
What Is PADIS?
Pain • Anxiety/Agitation • Delirium • Immobility • Sleep Disruption, the five domains of ICU suffering that drive morbidity, mortality, and post-ICU syndrome.
2025 SCCM Focused Update vs 2018 PADIS, At a Glance
CHANGEDDexmedetomidine suggested over propofol when light sedation (RASS 0 to −2) or delirium reduction are priorities. 2018: no preference between the two non-benzodiazepine agents; both considered equivalent. Why it matters: a resident asked about sedation choice should now lead with dex when these goals apply, not "either is fine." NEW 2025Melatonin suggested for ICU patients (3–5 mg PO at bedtime). May improve sleep quality and reduce delirium incidence. 2018: no recommendation; melatonin was off-label and informal. Now guideline-supported. EXPANDEDEnhanced mobilization/rehabilitation over usual care, including in-bed cycling, early initiation, twice-daily sessions, protocol-driven approaches, or extended duration. 2018: early mobilization recommended in general terms; 2025 specifies what "enhanced" means and asks for an intensification beyond baseline ICU PT. NEW 2025Anxiety added as a sixth domain. No specific intervention strongly recommended yet; emphasis on assessment and acknowledgment as a distinct ICU stressor. 2018 PADIS = Pain, Agitation/Sedation, Delirium, Immobility, Sleep only. The acronym is sometimes now written PADIS-A. CLARIFIEDAntipsychotics for delirium: unable to make a recommendation for or against (insufficient evidence for benefit on duration, LOS, or mortality). 2018: weak conditional against routine use for prevention; 2025 reframes the treatment evidence gap explicitly. Clinical bottom line is unchanged: do not use antipsychotics to "treat" delirium, only for safety-threatening agitation. UNCHANGEDAvoid benzodiazepines for routine ICU sedation (worsen delirium); analgesia-first approach (treat pain before escalating sedation); ABCDEF bundle; RASS, CAM-ICU/ICDSC, CPOT/BPS as screening tools; non-pharmacologic prevention as first-line for delirium. UNCHANGED All 2025 recommendations remain conditional with low-certainty evidence; individualize to each patient.
The ABCDEF Bundle
The ICU Liberation ABCDEF Bundle operationalizes PADIS at the bedside. Each element should be assessed daily:
Key Change:PADIS, 2025, Dexmedetomidine is now suggested over propofol for sedation in mechanically ventilated adults where light sedation (RASS 0 to −2) and/or delirium reduction are highest priorities.
Recommendation
2025 Status
vs 2018
Clinical Notes
Dexmedetomidine over propofol when light sedation or delirium reduction are priorities
Suggested Conditional, low certainty
CHANGED 2018: no preference between dex and propofol
Dexmedetomidine may reduce delirium incidence and improve time at target RASS. Higher risk of bradycardia and hypotension. NOT appropriate for deep sedation (RASS −4/−5) or patients needing NMBAs, dex cannot achieve that depth.
Propofol remains appropriate for rapid on/off sedation or deep sedation
Niche preserved Not displaced, just not preferred when light sedation is the goal
UNCHANGED Still first-line when deep sedation or fast neuro-check turnaround is needed
Faster wake-up for neuro checks and SAT/SBT. Monitor triglycerides q48h, hypertriglyceridemia is dose-related. Propofol infusion syndrome (PRIS) risk if > 80 mcg/kg/min for > 48h, watch for unexplained metabolic acidosis, rhabdo, bradycardia.
Avoid benzodiazepines for routine ICU sedation
Avoid (routine) Conditional
UNCHANGED 2018 already against routine use
Associated with increased delirium (OR ~2–3x), longer MV duration, longer ICU stay, worse cognitive outcomes. Reserve for alcohol withdrawal (CIWA-guided), seizures, or benzodiazepine-dependent patients.
Analgesia-first approach
Recommended Conditional
UNCHANGED 2018 core principle, carried forward
Treat pain before escalating sedation. Fentanyl infusion as first-line. Many patients labeled "agitated" are actually in untreated pain, sedation alone treats the wrong problem.
When to Choose What
Clinical Scenario
Preferred Agent
Rationale
Light sedation target (RASS 0 to −2)
Dexmedetomidine
Less delirium, preserves respiratory drive, cooperative sedation
Deep sedation needed (NMBAs, proning)
Propofol ± fentanyl
Titratable, rapid on/off. Dex inadequate for RASS −4/−5
Neuro checks needed frequently
Propofol
Fastest wake-up time for neurological assessment
Hemodynamically unstable / bradycardia risk
Propofol or fentanyl
Dex causes bradycardia and hypotension; avoid in shock
Alcohol withdrawal / seizure risk
Benzodiazepine (CIWA-guided)
Only appropriate indication for benzo ICU sedation
Post-extubation agitation / anxiety
Dexmedetomidine low-dose
Preserves airway reflexes; anxiolytic without respiratory depression
Daily Sedation Awakening Trial (SAT)
Protocol: Hold sedation each morning → assess RASS → if patient tolerates (RASS −1 to +1 without distress) → proceed to SBT. If agitation/distress → restart at 50% previous dose and titrate. ABC Trial, 2008: paired SAT + SBT reduced ventilator days by 3.1 days and 1-year mortality by 14%.
🧠 Delirium
Delirium: 2025 Update
2025 Key Finding: The PADIS task force was unable to recommend for or against antipsychotics for ICU delirium. Current evidence shows minimal or no effect on ICU/hospital length of stay. Focus on non-pharmacologic prevention first.
CAM-ICU Screening (Assess q8-12h)
Feature
Assessment
Positive If
1. Acute onset / fluctuating course
Change from baseline OR fluctuating mental status in past 24h?
Yes
2. Inattention
Squeeze my hand when I say "A", S-A-V-E-A-H-A-A-R-T
< 8/10 correct (errors > 2)
3. Altered consciousness
RASS score at time of assessment
RASS ≠ 0 (any score other than alert/calm)
4. Disorganized thinking
"Will a stone float on water?" "Are there fish in the sea?" + command
Correct sensory deficits, glasses, hearing aids at bedside
Family presence, familiar voices reduce agitation and disorientation
Music therapy, familiar music may reduce anxiety and agitation
Melatonin, now formally suggested PADIS, 2025
Pharmacologic Management
Drug
Dose
Evidence
2025 vs 2018
Haloperidol (Haldol)
0.5–2 mg IV/IM q4-6h PRN
HOPE-ICU, 2013 and MIND-USA, 2018: no benefit on delirium duration, coma-free days, or mortality. AID-ICU, 2022 reinforced no mortality benefit.
CLARIFIED 2025: no recommendation for or against. 2018: weak conditional against routine use for prevention. Clinical bottom line unchanged, only for safety-threatening agitation, not as a delirium "treatment."
Quetiapine (Seroquel)
25–200 mg PO BID
Limited evidence, may reduce delirium duration in small trials. Preferred when haldol contraindicated (Parkinson's, Lewy body dementia).
CLARIFIED 2025: no recommendation for or against, same as 2018. Use only when antipsychotic is genuinely needed.
Dexmedetomidine
0.2–1.5 mcg/kg/hr IV
MENDS, 2007: more delirium-free and coma-free days vs lorazepam. SEDCOM, 2009: less delirium (54% vs 76.6%) and shorter time to extubation vs midazolam. DahLIA, 2016: faster resolution of agitated delirium.
ELEVATED 2025: suggested over propofol when light sedation or delirium reduction prioritized. 2018: dex and propofol considered equivalent.
Melatonin
3–5 mg PO at bedtime
Low-risk intervention. May improve sleep quality and reduce delirium incidence. Note: not FDA-regulated, brand-to-brand variability in bioavailability.
NEW 2025 2018: no recommendation, off-label use only. Now formally suggested.
Avoid: Benzodiazepines for delirium treatment (worsen delirium). Physical restraints should be minimized, they increase agitation and prolong delirium. QTc monitoring required for all antipsychotics.
🏃 Mobility & Sleep
Enhanced Mobilization (2025 Recommendation)
New:PADIS, 2025, Enhanced mobilization/rehabilitation is suggested over usual care. Enhancements include cycling, early initiation, twice-daily sessions, protocol-driven approaches, or extended duration.
Mobilization Levels
Level
Activity
When
0
Passive ROM in bed
Hemodynamically unstable, on NMBAs, high FiO₂
1
Active-assisted ROM in bed, bed exercises
On vasopressors but stable, mechanical ventilation
2
Sitting on edge of bed (dangle)
RASS ≥ −2, FiO₂ ≤ 0.6, vasopressors weaning
3
Standing, transfer to chair
Cooperative, stable vitals, able to follow commands
4
Ambulation (with or without assist)
Off vasopressors, tolerating lower vent support or extubated
Safety Screen Before Mobilization
MAP < 60 or > 110, or new/escalating vasopressors
Active cardiac ischemia or unstable arrhythmia
SpO₂ < 88% on current settings
Active seizures, raised ICP, or unstable spine
Active hemorrhage or unsecured airway
Patient refusal or extreme distress
Sleep Disruption
New:PADIS, 2025, Melatonin is now suggested for ICU patients. Low-risk intervention that may improve sleep quality and reduce delirium. Note: not FDA-regulated, so quality may vary between brands.
ICU Sleep Bundle
Environmental: Dim lights 10 PM–6 AM, minimize alarms, cluster care to allow 4h uninterrupted sleep
Pharmacologic: Melatonin 3–5 mg PO at 9 PM. Avoid benzos and zolpidem (worsen delirium)
Ventilator: Optimize settings to minimize discomfort/dyssynchrony at night
Sensory: Offer ear plugs and eye masks (shown to improve sleep quality in RCTs)
First-line analgesia. Less hypotension than morphine. Accumulates in renal/hepatic failure.
Dexmedetomidine (Precedex)
0.2–1.5 mcg/kg/hr IV
5–10 min
PADIS 2025 preferred for light sedation. Bradycardia risk. No respiratory depression. Anxiolytic.
Propofol (Diprivan)
5–50 mcg/kg/min IV
30–60 sec
Fastest wake-up. Monitor TGs q48h. Propofol infusion syndrome (PRIS) risk if > 80 mcg/kg/min > 48h. Best for neuro checks.
Midazolam (Versed)
0.02–0.1 mg/kg/hr IV
2–3 min
Avoid for routine sedation (↑ delirium). Reserve for alcohol withdrawal/seizures. Accumulates.
Ketamine
0.1–0.5 mg/kg/hr IV
1–2 min
Opioid-sparing analgesic. Useful in refractory pain or bronchospasm. Emergence reactions.
Melatonin
3–5 mg PO at bedtime
30–60 min
PADIS 2025 new recommendation. Sleep promotion. May reduce delirium. Not FDA-regulated.
Haloperidol (Haldol)
0.5–2 mg IV/IM q4-6h PRN
10–20 min
No PADIS recommendation for delirium. QTc monitoring. Risk of EPS. Use only for acute safety threats.
Hypersalivation / Sialorrhea
Common in the ICU from ketamine infusions, clozapine, bulbar dysfunction (stroke, ALS, post-extubation weakness), or simply an inability to clear pooled oropharyngeal secretions. Listed most common to least common.
Drug
Dose
Key Points
Glycopyrrolate (Robinul)
0.1–0.2 mg IV q4–6h PRN, or 1–2 mg PO/NG TID
First-line in ICU. Does not cross the blood-brain barrier, so no delirium risk (unlike IV atropine or scopolamine). Workhorse for ketamine infusions, clozapine drooling, and post-extubation secretions.
Atropine 1% ophthalmic drops
1–2 drops sublingual q4–6h
Off-label but cheap and effective. Minimal systemic absorption. Useful when the patient cannot swallow pills.
Scopolamine patch (Transderm Scōp)
1.5 mg transdermal q72h
Convenient sustained effect but 6–12 h to onset. Avoid in elderly or already delirious patients (CNS anticholinergic effects).
Hyoscyamine (Levsin)
0.125 mg SL q4h PRN
Alternative when glycopyrrolate is unavailable.
Ipratropium
500 mcg nebulized q6h, or SL
Reserve for refractory cases or when other routes are limited.
Chronic or refractory sialorrhea only (bulbar ALS, Parkinson, cerebral palsy). Effect lasts ~3 months.
Address the cause: Ketamine infusion: glycopyrrolate premedication is standard. Clozapine: dose reduction or scheduled glycopyrrolate (do not abruptly stop clozapine). Organophosphate toxicity: atropine plus pralidoxime (different problem). Bulbar / neuro: glycopyrrolate plus Yankauer suction, head of bed up, swallow evaluation.
Watch for anticholinergic load: urinary retention, ileus, tachycardia, delirium, dry eyes. Stack carefully if the patient is already on other anticholinergics.
📋 On Rounds
Pimp Questions
What sedation agent does PADIS 2025 suggest over propofol, and when?
Dexmedetomidine is suggested over propofol when light sedation (RASS 0 to −2) and/or delirium reduction are the highest priorities. It reduces delirium incidence but carries higher risk of bradycardia. NOT appropriate for deep sedation or hemodynamic instability.
Does PADIS 2025 recommend antipsychotics for ICU delirium?
No. The task force was unable to issue a recommendation for or against antipsychotics for delirium treatment. MIND-USA, 2018 and other trials show minimal or no effect on ICU/hospital LOS. Focus on non-pharmacologic prevention: reorientation, sleep hygiene, early mobilization, minimizing deliriogenic meds.
What is the ABCDEF bundle and why does it matter?
A = Assess/prevent/manage pain, B = Both SAT + SBT daily, C = Choice of sedation (dex or propofol, avoid benzos), D = Delirium assess/prevent/manage, E = Early mobilization, F = Family engagement. Operationalizes PADIS guidelines at the bedside. Bundle compliance associated with lower mortality, less delirium, and shorter ICU stays.
When is propofol preferred over dexmedetomidine?
When deep sedation is required (RASS −4/−5 for NMBAs or proning), when frequent neuro checks need rapid wake-up, or when the patient has hemodynamic instability or bradycardia risk. Dex cannot achieve deep sedation and may worsen hypotension/bradycardia.
What does PADIS 2025 say about melatonin in the ICU?
Melatonin is now conditionally suggested for ICU patients (3–5 mg PO at bedtime). It is a low-risk intervention that may improve sleep quality and reduce delirium incidence. Caveat: melatonin is not FDA-regulated, so quality and bioavailability may vary between brands. Optimal dosing is still being studied.
Why should you avoid benzodiazepines for routine ICU sedation?
Benzodiazepines are independently associated with increased delirium (OR ~2–3x), longer duration of mechanical ventilation, longer ICU stay, and worse cognitive outcomes. PADIS, 2018 recommended non-benzodiazepine sedation. The only appropriate ICU indications are alcohol withdrawal (CIWA-guided), active seizures, and benzodiazepine-dependent patients.
What enhanced mobilization strategies does PADIS 2025 suggest?
Enhanced mobilization includes: in-bed cycling, early initiation (within 48h), twice-daily sessions, protocol-driven approaches, or extended duration of mobility. Schweickert, 2009: early PT/OT improved functional independence and reduced delirium duration. Goal is to mitigate ICU-acquired weakness and its long-term impact on survival and quality of life.
Daily ICU Sedation Checklist
RASS score, Current? At target (0 to −2)?
Pain assessment, CPOT/BPS. Analgesia adequate before sedation adjustment?
CAM-ICU, Delirium screen this shift?
SAT eligibility, Can we hold sedation today?
SBT eligibility, If SAT passed, ready for breathing trial?
Deliriogenic meds, Can we stop benzos, anticholinergics, unnecessary opioids?
Family, Visitation plan? Family meeting needed?
📋 Sample Presentation
"Mrs. Chen is on ICU day 3, intubated for ARDS. Sedation: dexmedetomidine at 0.8 mcg/kg/hr with fentanyl 75 mcg/hr. RASS is −1, at our target. CAM-ICU was negative this morning. We did a SAT, she tolerated the sedation hold and proceeded to an SBT, which she passed. Plan is to extubate today. PT had her dangling yesterday. Melatonin 3 mg at bedtime. No benzodiazepines. Family has been at bedside with open visitation."
Skeletal muscle breakdown releasing myoglobin, CK, potassium, and phosphate into the circulation. Myoglobin causes direct renal tubular obstruction and toxicity → AKI. The three killers: hyperkalemia, AKI, and compartment syndrome. Treatment is aggressive IV hydration -dilute the myoglobin before it destroys the kidneys.
🔍 Overview
Definition
Rhabdomyolysis: Skeletal muscle necrosis with release of intracellular contents (myoglobin, CK, potassium, phosphate, uric acid, LDH) into the circulation. Defined as CK > 5× upper limit of normal (typically > 1,000 U/L, often > 5,000–10,000 in clinically significant cases). CK levels > 10,000 carry a high risk of AKI.
Pathophysiology
Myocyte necrosis (any cause) → release of myoglobin into bloodstream → myoglobin filtered by glomerulus → in acidic urine, myoglobin precipitates as ferrihemate casts → direct renal tubular obstruction + oxidative injury to tubular epithelium + renal vasoconstriction → acute tubular necrosis (ATN) → AKI. Simultaneously, massive release of intracellular K⁺ → life-threatening hyperkalemia, and PO₄ release → hypocalcemia (calcium binds to damaged muscle and phosphate).
Common Causes
Trauma/crush injury -earthquakes, prolonged immobilization, surgery
Immobilization -found down (overdose, stroke, fall), prolonged surgery
Drugs of abuse -cocaine, amphetamines, MDMA, PCP, synthetic cannabinoids
Infections -influenza, HIV, Legionella, group A strep
Clinical Example
Case
22M found down after a party (likely substance use + prolonged immobilization). Presenting with diffuse myalgias, dark brown urine, and oliguria. Labs: CK 45,000, K⁺ 6.2, Cr 3.4, Ca²⁺ 7.1, PO₄ 6.8, uric acid 12. UA: positive for blood on dipstick but 0 RBCs on microscopy (= myoglobinuria). ECG shows peaked T-waves.
🚨 Management
Treatment Protocol
The THREE killers in rhabdo: (1) Hyperkalemia -can be rapid and fatal, check K⁺ q4–6h. (2) AKI -from myoglobin-induced tubular necrosis. (3) Compartment syndrome -if a limb is involved, check compartment pressures.
Priority
Intervention
Details
1. Aggressive IV fluids
NS or LR at 200–300 mL/hr
Target UOP 200–300 mL/hr (much higher than standard resuscitation). Goal: dilute myoglobin and prevent tubular precipitation. Most patients need 6–10 L in first 24h. Foley catheter mandatory for strict I&Os.
Check K⁺ q4–6h. If K⁺ > 6.0 or ECG changes → calcium gluconate 1g IV for cardiac membrane stabilization → insulin 10 units + D50 for K⁺ shift → kayexalate or patiromer for removal. See Hyperkalemia.
3. Bicarb (controversial)
Sodium bicarbonate 150 mEq in 1L D5W
Goal: urine pH > 6.5 to keep myoglobin soluble. Controversial -theoretical benefit but no strong RCT evidence. May worsen hypocalcemia (alkalosis binds ionized Ca). Consider if urine pH < 6.5.
4. Compartment check
Measure compartment pressures
If limb injury involved or tense/swollen extremity. Pressure > 30 mmHg or within 30 mmHg of diastolic → emergent fasciotomy. Ortho/surgery consult.
5. Dialysis (if needed)
Continuous RRT (CRRT) preferred
Indications: refractory hyperkalemia, volume overload, severe acidosis, uremia. Standard HD does NOT clear myoglobin (too large). CRRT may have theoretical benefit.
Do NOT give calcium for hypocalcemia in rhabdo (unless symptomatic with tetany or ECG changes) -calcium deposits in damaged muscle and worsens injury. The calcium will correct on its own as muscles heal.
🧪 Workup
Laboratory Workup
CK (creatine kinase) -diagnostic. Serial q6–12h until trending down. Peak usually at 24–72h. CK > 5,000 = significant rhabdo risk for AKI.
Urinalysis -dipstick positive for blood but NO RBCs on microscopy = myoglobinuria. This is a classic boards question. The heme pigment on the dipstick cross-reacts with myoglobin.
LDH -elevated (nonspecific muscle injury marker)
Uric acid -often elevated (cell lysis)
Coags (PT/INR, aPTT, fibrinogen) -DIC risk with severe rhabdo
Lactate -tissue hypoperfusion marker
Urine myoglobin -can confirm but not widely available and clears quickly. UA dipstick is adequate.
AST/ALT Pattern in Rhabdo, Looks Like Hepatitis but Isn't
Rhabdo routinely produces ↑ AST (often 200–800 U/L) and ↑ ALT (smaller bump), with AST > ALT. AST is leaked from lysed myocytes, not made by injured liver (skeletal muscle is constitutively rich in AST; ALT is present in muscle but at lower concentration). If CK is high, attribute the LFT abnormality to muscle and don't chase viral hepatitis serologies. AST/ALT will trend down as CK drops.
Why it matters: A patient with AST 400 / ALT 250 / AST > ALT after a found-down event or seizure does not need a hepatitis B/C panel. Check CK first. Wasted serology workup delays the only thing that helps the kidneys, aggressive hydration to UOP 200–300 mL/hr.
Red flags that argue for true hepatic injury (look elsewhere if any are present): AST/ALT in the thousands without matching CK, ↑ INR, ↑ bilirubin out of proportion to CK, encephalopathy, or AST/ALT not tracking CK on serial labs (real liver injury usually means ischemic hepatitis from shock, drug-induced injury, or alcoholic hepatitis).
Myoglobin vs Hemoglobin, Same Heme but Different Fate
Both proteins contain heme, but their clinical signatures diverge sharply, and this is a common point of confusion:
Myoglobin → kidney → urine (causes AKI, not jaundice). Filtered freely by the glomerulus (~17 kDa, small enough to pass). In acidic urine it precipitates as ferrihemate casts → tubular obstruction + oxidative injury to tubular epithelium + renal vasoconstriction → acute tubular necrosis. This is why rhabdo presents with tea-colored urine and AKI, the myoglobin gets excreted in urine before it can be metabolized to anything else.
Hemoglobin → spleen → bilirubin (causes jaundice when pathologic). Senescent RBCs are phagocytosed by splenic macrophages. Heme oxygenase converts heme to biliverdin; biliverdin reductase converts biliverdin to unconjugated bilirubin, which then travels to the liver for conjugation and biliary excretion. This pathway accounts for ~80% of daily bilirubin production.
Why the distinction matters: Myoglobin technically can yield trace bilirubin via the same heme-oxygenase pathway (the chemistry is identical), but clinically it doesn't produce jaundice because it's excreted in urine first. If a rhabdo patient is jaundiced, look elsewhere, hemolysis (free hemoglobin overwhelming haptoglobin → bilirubin surge), ischemic hepatitis from shock (AST in the thousands, ↑ LDH, ↑ INR), or drug-induced hepatic injury. Don't blame the myoglobin.
💊 Medications
Rhabdomyolysis Medications
Drug
Dose
Route
Role
Normal Saline or LR
200–300 mL/hr
IV
FIRST-LINE -aggressive volume resuscitation to target UOP 200–300 mL/hr. LR may be preferred (less hyperchloremic acidosis) but avoid if K⁺ > 6.0 (contains 4 mEq/L K⁺).
Sodium bicarbonate
150 mEq in 1L D5W
IV infusion
Urine alkalinization (target pH > 6.5). Controversial -no RCT evidence of benefit. Consider if urine pH < 6.5.
Calcium gluconate
1–2 g IV over 10 min
IV
ONLY for hyperkalemia with ECG changes. Do NOT give for asymptomatic hypocalcemia.
Insulin (regular) + D50
10 units IV + 25g D50
IV
K⁺ shifting for hyperkalemia. Onset 15–30 min, lasts 4–6h.
Kayexalate / Patiromer
Kayexalate 30g PO; Patiromer 8.4g PO
PO
K⁺ removal (delayed onset). Patiromer preferred (fewer GI side effects).
Monitoring Parameters
Parameter
Frequency
Target / Action
Urine output
Hourly (Foley required)
Target 200–300 mL/hr. If not meeting target, increase IV rate. If oliguric despite adequate fluids → nephrology consult.
CK (creatine kinase)
q6–12h
Trend to peak and decline. Stop aggressive IVF when CK trending down and < 5,000.
BMP (K⁺, Ca, PO₄, Cr)
q6h initially
K⁺ is the most dangerous -check frequently. Cr trend for AKI progression.
Why is the UA positive for blood but shows no RBCs on microscopy?
The urine dipstick detects the heme pigment (peroxidase activity) -it cannot distinguish between hemoglobin and myoglobin. In rhabdomyolysis, myoglobin is filtered by the glomerulus and appears in the urine. The dipstick reads this as "blood positive," but when you spin the urine and look under the microscope, there are no red blood cells. This combination -dipstick + for blood, no RBCs on micro -is the classic finding of myoglobinuria.
When should you start dialysis in rhabdomyolysis?
Standard indications for dialysis (AEIOU): Acidosis (severe, refractory to bicarb), Electrolytes (refractory hyperkalemia despite medical management), Ingestion (toxic), Overload (volume overload not responding to diuretics), Uremia (encephalopathy, pericarditis, bleeding). In rhabdo specifically, the most common indication is refractory hyperkalemia. Note: conventional hemodialysis does NOT efficiently clear myoglobin (molecular weight ~17 kDa)
Why should you avoid giving calcium for hypocalcemia in rhabdomyolysis?
In rhabdomyolysis, calcium is sequestered in damaged muscle tissue (binds to necrotic myocytes) and is also bound by elevated phosphate. This causes a transient hypocalcemia that is expected and self-limited -it will correct on its own as muscles heal and release the sequestered calcium (often causing rebound hypercalcemia in the recovery phase).
Clinical Examples
📋 Case 1, Found Down with Rhabdomyolysis
Patient: 34M found unresponsive on floor for unknown duration. PMH opioid use disorder. GCS 10 on arrival. Dark brown urine noted on Foley insertion.
Key findings: CK 85,000 IU/L. K+ 6.2. Cr 3.1 (baseline unknown). UA: dipstick positive for blood, no RBCs on microscopy (myoglobinuria). R gluteal compartment firm and tender.
Management:
Aggressive IV crystalloid (NS or LR) 200-300 mL/hr targeting UOP 200-300 mL/hr
Treat hyperkalemia: calcium gluconate 3g IV (ECG changes present), insulin 10 units + D50, kayexalate
Do NOT give calcium for hypocalcemia (will worsen muscle injury), only for hyperK with ECG changes
Monitor CK, K+, Cr, phosphorus q4-6h
Orthopedic surgery consult for compartment pressure measurement
Teaching point: Immobilization ("found down") is one of the most common causes of rhabdomyolysis. The three killers are hyperkalemia (check K+ q4-6h), AKI (myoglobin tubular necrosis), and compartment syndrome. Dipstick positive for blood with no RBCs on microscopy is the classic myoglobinuria finding.
📋 Case 2, Statin-Induced Rhabdomyolysis
Patient: 68F, PMH hyperlipidemia, CKD stage 3. Started simvastatin 80 mg 3 weeks ago (recently added clarithromycin for pneumonia). Presents with diffuse myalgias, weakness, tea-colored urine.
IV fluids 200-300 mL/hr (adjust for CKD, monitor for volume overload)
Target UOP 200-300 mL/hr
Avoid calcium for asymptomatic hypocalcemia
When recovered: switch to rosuvastatin or pravastatin (not CYP3A4 metabolized)
Teaching point: Statins metabolized by CYP3A4 (simvastatin, atorvastatin, lovastatin) have dangerous interactions with CYP3A4 inhibitors (macrolides, azole antifungals, protease inhibitors). Rosuvastatin and pravastatin are safer alternatives because they are not CYP3A4 substrates.
📋 Case 3, Rhabdomyolysis with Compartment Syndrome
Patient: 25M after crush injury to R leg (motor vehicle accident). CK 120,000. R anterior leg tense, exquisitely painful with passive stretch of toes. Distal pulses present.
Do NOT wait for all 5 P's, pulselessness means irreversible damage has occurred
Continue aggressive IV fluids for rhabdomyolysis
Monitor for reperfusion injury after fasciotomy (may worsen hyperkalemia transiently)
Serial CK and K+ monitoring post-fasciotomy
Teaching point: Compartment syndrome is a clinical/manometric diagnosis. Delta pressure (diastolic BP - compartment pressure) < 30 mmHg is an indication for emergent fasciotomy. Pulses may be preserved even with critical compartment pressures, do not rely on distal pulses to rule out compartment syndrome.
⚡ Summary
Rhabdomyolysis -Key Points
Diagnose It on CK Plus Context
CK above about 5 times the upper limit, typically above 1,000, with muscle pain, weakness and dark urine.A urine dipstick positive for blood with no red cells on microscopy is myoglobinuria, and that mismatch is the fastest bedside confirmation. CK peaks at 24 to 72 h and falls with a predictable half-life, so a plateau or a second rise means ongoing injury.
Fluids Are the Treatment
Aggressive isotonic IV fluid, starting at 1 to 2 L/h in severe cases, titrated to a urine output of 200 to 300 mL/h.The point is to dilute the myoglobin and flush it through the tubules before it obstructs and poisons them.The volume required is far larger than instinct suggests, because muscle sequesters enormous amounts of fluid.
The Three Killers
Hyperkalemia, which can be rapid and fatal, so check potassium every 4 to 6 h.Acute kidney injury from myoglobin-induced tubular necrosis.Compartment syndrome, so check compartment pressures if a limb is involved and remember it can develop after fluid resuscitation, not just before it.
Do Not Give Calcium for the Hypocalcemia
Unless there is tetany or ECG change.Calcium deposits in damaged muscle and worsens the injury, and it is then released later as the muscle heals, producing rebound hypercalcemia. The calcium corrects itself.
Read the Transaminases as Muscle
AST and ALT are both released from muscle, so they rise in rhabdomyolysis and look like hepatitis.AST rises higher and falls faster than ALT, and the bilirubin and alkaline phosphatase stay normal. Recognizing this stops an unnecessary hepatitis workup in a patient whose problem is entirely muscular.
Know the Causes
Trauma and crush injury, prolonged immobilization (the elderly patient found down), seizures, extreme exertion, hyperthermia including NMS and malignant hyperthermia, drugs (statins, especially with a fibrate or an interacting CYP inhibitor; cocaine; alcohol), infections, and electrolyte disturbances.Recurrent unexplained rhabdomyolysis after modest exertion suggests an inherited metabolic myopathy and warrants referral.
Bicarbonate and Mannitol Are Not Established
Neither has convincing evidence over adequate isotonic fluid alone. Urinary alkalinization is a reasonable adjunct in severe cases if the pH allows, but it risks worsening hypocalcemia. Do not let a debate about them delay or displace volume resuscitation, which is the intervention that works.
Know When Dialysis Is Needed and When to Stop Fluids
Dialyze for the usual indications: refractory hyperkalemia, refractory acidosis, volume overload and uremia, not for the CK level itself, since standard hemodialysis clears myoglobin poorly. Stop the aggressive fluids once CK is falling and urine output is established, since continuing them into a patient with established oliguric AKI causes pulmonary edema.
RoundsRx Infographic Series · #121 · Renal & Metabolic · PDF 140 KB
EMERGENTNeuro
NMS vs Serotonin Syndrome
Two life-threatening drug-induced hyperthermic syndromes that look similar but have different causes, key findings, and treatments. NMS = dopamine blockade (antipsychotics) with RIGIDITY. Serotonin syndrome = serotonin excess (SSRIs, MAOIs) with CLONUS. Getting the diagnosis right determines the treatment.
🔍 Overview
Side-by-Side Comparison
The #1 distinguishing feature: NMS = RIGIDITY (lead-pipe), SS = CLONUS (hyperreflexia). If the patient is stiff everywhere → think NMS. If they're twitching/jerking → think SS.
Feature
NMS
Serotonin Syndrome
Mechanism
Dopamine ANTAGONISM (decreased dopamine)
Serotonin EXCESS (increased serotonin)
Causative drugs
Haloperidol, olanzapine, risperidone, metoclopramide, prochlorperazine. Also sudden withdrawal of dopamine agonists (levodopa).
NMS results from acute dopamine D2 receptor blockade in the hypothalamus (thermoregulation failure) and basal ganglia (rigidity). Most common with high-potency antipsychotics (haloperidol) but can occur with ANY dopamine antagonist -including metoclopramide (Reglan) and prochlorperazine (Compazine). Can also occur with abrupt withdrawal of dopaminergic agents (levodopa in Parkinson's patients). Mortality: 10–20% if untreated.
Serotonin Syndrome -Hunter Criteria
Diagnosed using the Hunter Serotonin Toxicity Criteria (most accurate) in a patient on a serotonergic drug: (1) Spontaneous clonus, OR (2) Inducible clonus + agitation or diaphoresis, OR (3) Ocular clonus + agitation or diaphoresis, OR (4) Tremor + hyperreflexia, OR (5) Hypertonia + temperature > 38°C + ocular or inducible clonus. Key drug interaction to know:linezolid is a reversible MAOI -can precipitate SS when combined with SSRIs/SNRIs. This is a classic boards trap.
🚨 Management
NMS Treatment Algorithm
Step
Intervention
Details
1. STOP offending agent
Discontinue ALL antipsychotics/dopamine antagonists
This is the most important step. If NMS from levodopa withdrawal → restart levodopa immediately.
2. Aggressive cooling
Ice packs, cooling blankets, cold IV fluids
Target temp < 39°C. Antipyretics (acetaminophen) do NOT work -this is not cytokine-mediated fever, it's muscle-generated heat.
3. Dantrolene
Dantrolene (Dantrium) 1–2.5 mg/kg IV
Direct-acting muscle relaxant (blocks ryanodine receptor → reduces Ca²⁺ release from SR → reduces muscle contraction and heat generation). May repeat q5–10 min to max 10 mg/kg/day.
4. Bromocriptine
Bromocriptine (Parlodel) 2.5 mg PO/NG q8h
Dopamine agonist -directly counteracts the dopamine blockade causing NMS. Continue for 10 days after NMS resolves (prevent relapse).
5. Supportive
ICU admission, IVF, monitoring
Watch for rhabdomyolysis (check CK), AKI, DIC, aspiration, respiratory failure. Intubation may be needed.
Serotonin Syndrome Treatment Algorithm
Step
Intervention
Details
1. STOP offending agent
Discontinue ALL serotonergic drugs
Most cases resolve within 24h of stopping the offending drug(s). Review full medication list carefully.
2. Benzodiazepines
Lorazepam 1–2 mg IV or diazepam 5–10 mg IV
FIRST-LINE -controls agitation, reduces muscle activity and heat generation, lowers seizure threshold. Repeat as needed.
3. Cyproheptadine
Cyproheptadine (Periactin) 12 mg PO/NG load, then 2 mg q2h
Serotonin 5-HT2A antagonist -directly blocks excess serotonin. Only available PO/NG (no IV form). Max 32 mg/day.
4. Cooling
External cooling measures
For temperature > 41°C. Avoid antipyretics (ineffective).
5. Avoid
Do NOT give antipsychotics for agitation
Some antipsychotics have serotonergic activity and could worsen SS. Do NOT give dantrolene (ineffective -muscle activity in SS is from neural excitation, not peripheral).
🧪 Workup
Laboratory Workup (Both NMS and SS)
CK (creatine kinase) -markedly elevated in NMS (often > 1,000, can be > 10,000). Mildly elevated or normal in SS.
BMP -Cr (AKI from rhabdo in NMS), K⁺ (hyperK from muscle breakdown), glucose
CBC -leukocytosis common in NMS (not from infection -stress response)
LFTs -may be elevated in NMS (hepatic injury)
Coags (PT/INR, aPTT, fibrinogen) -DIC screening in severe NMS
UA -myoglobinuria in NMS (dipstick + blood, no RBCs)
TSH -rule out thyroid storm (hyperthermia + tachycardia differential)
Toxicology screen -rule out sympathomimetic toxicity, anticholinergic syndrome
Medication reconciliation -CRITICAL. Identify the offending drug(s). Review ALL medications, supplements, and OTC drugs for serotonergic or dopamine-blocking activity.
💊 Medications
Key Medications
Drug
Dose
Indication
Key Notes
Dantrolene (Dantrium)
1–2.5 mg/kg IV, repeat q5–10 min
NMS only
Direct muscle relaxant (ryanodine receptor blocker). Max 10 mg/kg/day. Monitor for hepatotoxicity. NOT for SS.
Bromocriptine (Parlodel)
2.5 mg PO/NG q8h
NMS only
Dopamine agonist -directly counteracts D2 blockade. Continue 10 days after resolution. Can also use amantadine 100 mg PO q12h.
Cyproheptadine (Periactin)
12 mg PO/NG load, then 2 mg q2h
SS only
5-HT2A antagonist. PO only (no IV form). Max 32 mg/day. Sedating (antihistamine). NOT for NMS.
Lorazepam
1–2 mg IV PRN
SS first-line; adjunct in NMS
Controls agitation, reduces muscle hyperactivity, prevents seizures. Can use diazepam 5–10 mg IV as alternative.
📋 On Rounds
What is the key distinguishing physical exam finding between NMS and Serotonin Syndrome?
NMS = Lead-pipe RIGIDITY. The patient is stiff, with diffuse muscle rigidity that resists passive movement uniformly throughout the range of motion (like bending a lead pipe). Reflexes may be normal or diminished. SS = CLONUS + hyperreflexia. The patient has rhythmic, involuntary muscular contractions (especially in lower extremities -ankle clonus), plus brisk/exaggerated deep tendon reflexes. Tremor is also common.
Can linezolid cause serotonin syndrome?
Yes!Linezolid (Zyvox) is a reversible, nonselective monoamine oxidase inhibitor (MAOI) in addition to being an oxazolidinone antibiotic. When given to patients already on SSRIs, SNRIs, or other serotonergic drugs, it can precipitate serotonin syndrome. This is a classic boards question and a real clinical trap -always check the medication list before starting linezolid.
Why is bromocriptine used in NMS?
Bromocriptine (Parlodel) is a dopamine D2 receptor agonist. NMS is caused by dopamine D2 blockade (from antipsychotics or other dopamine antagonists), leading to loss of thermoregulation (hypothalamus), rigidity (basal ganglia), and autonomic instability. Bromocriptine directly counteracts the dopamine blockade by stimulating D2 receptors. It restores dopaminergic tone in the hypothalamus and basal ganglia.
What are the Hunter Criteria for Serotonin Syndrome?
The Hunter Serotonin Toxicity Criteria are the most sensitive (84%) and specific (97%) diagnostic criteria for SS. In a patient taking a serotonergic agent, ANY ONE of the following: (1) Spontaneous clonus. (2) Inducible clonus + agitation OR diaphoresis. (3) Ocular clonus + agitation OR diaphoresis. (4) Tremor + hyperreflexia. (5) Hypertonia + temperature > 38°C + (ocular clonus OR inducible clonus).
Clinical Examples
📋 Case 1, Neuroleptic Malignant Syndrome
Patient: 34M brought to ED after found confused at group home. Started haloperidol 10 mg IM 3 days ago for acute psychosis. Temp 40.2°C, HR 128, BP 170/95. Diffuse lead-pipe rigidity.
ICU admission, continuous temperature monitoring, serial CK q6h
Teaching point: NMS = "lead-pipe rigidity" with slow onset (days). High-potency typical antipsychotics (haloperidol) are highest risk. CK is often dramatically elevated (> 1000).
📋 Case 2, Serotonin Syndrome
Patient: 45F on sertraline 200 mg daily, presents 6 hours after starting tramadol for back pain. Temp 38.6°C, HR 112, agitated, diaphoretic. Bilateral ankle clonus, hyperreflexia throughout. Dilated pupils.
Key findings: Hunter Criteria positive: inducible clonus + agitation + diaphoresis. Precipitant: addition of tramadol (serotonergic) to SSRI. CK 380 (mildly elevated). Onset within hours.
Management:
Stop all serotonergic agents (sertraline and tramadol)
Benzodiazepines for agitation: lorazepam 2 mg IV PRN
Active cooling if temp > 40°C; avoid antipyretics (ineffective, heat is from muscle activity)
IVF resuscitation, cardiac monitoring, most cases resolve within 24-72h
Teaching point: SS = "clonus + hyperreflexia" with rapid onset (hours). Key distinguisher from NMS: clonus and hyperreflexia (NMS has rigidity and hyporeflexia). Tramadol is a commonly missed serotonergic agent.
📋 Case 3, NMS vs Serotonin Syndrome Diagnostic Dilemma
Patient: 58M on quetiapine and duloxetine, presents with confusion, temp 39.4°C, diaphoresis, tremor. Exam: increased tone in lower extremities, 3+ reflexes bilaterally, bilateral ankle clonus.
Key findings: On both an antipsychotic (quetiapine) and serotonergic agent (duloxetine). CK 620. Features overlap: fever + AMS + autonomic instability present in both conditions.
Start cyproheptadine 12 mg PO load (treat as SS given clonus)
Benzodiazepines for agitation and muscle hyperactivity
Monitor CK trending, if > 5000 or rising, add dantrolene for possible NMS component
Teaching point: The exam is the key differentiator: NMS → lead-pipe rigidity + hyporeflexia. SS → clonus + hyperreflexia + tremor. When in doubt, treat both, cyproheptadine won't worsen NMS, and supportive care overlaps.
Monitoring Parameters
Parameter
Frequency
Target / Action
Temperature
q1–2h
Target < 39°C. Active cooling if > 40°C. Antipyretics ineffective.
CK
q6–12h (NMS)
Trend for rhabdomyolysis severity. If rising → aggressive IVF for renal protection.
NMS is rigidity, lead-pipe and generalized. Serotonin syndrome is clonus and hyperreflexia, most marked in the lower limbs.Stiff everywhere means NMS; twitching and jerking means serotonin syndrome. Getting this right determines the whole treatment.
Timing and Trigger Differ Too
NMS: dopamine blockade from antipsychotics, or abrupt withdrawal of a dopamine agonist, developing slowly over days to weeks.Serotonin syndrome: serotonin excess from SSRIs, SNRIs, MAOIs, tramadol, linezolid, triptans, ondansetron or dextromethorphan, developing within 24 h of a new drug or a dose increase.The medication history and its timeline usually make the diagnosis before the examination does.
Use Hunter Criteria for Serotonin Syndrome
Serotonergic exposure plus spontaneous clonus, or inducible or ocular clonus with agitation or diaphoresis, or tremor with hyperreflexia, or hypertonia with a temperature above 38°C plus ocular or inducible clonus.Check ankle clonus deliberately: it is the most useful bedside sign and it is easy to omit.
Stop the Drug and Support, in Both
Discontinue the offending agent immediately, give aggressive IV fluids, cool actively, and use benzodiazepines for agitation and rigidity.Benzodiazepines are first line in serotonin syndrome and are useful in both. Most serotonin syndrome resolves within 24 h with supportive care alone.
Specific Agents Differ
NMS: dantrolene for severe rigidity and hyperthermia, plus bromocriptine or amantadine to restore dopaminergic tone.Serotonin syndrome: cyproheptadine, a 5-HT2A antagonist, for moderate to severe cases.Giving a dopamine agonist for serotonin syndrome, or cyproheptadine for NMS, treats the wrong receptor.
Never Use Antipyretics or Physical Restraints
The hyperthermia is muscular, not hypothalamic, so acetaminophen and NSAIDs do nothing. Cool physically and paralyze if the temperature is above about 41°C, using a non-depolarizing agent. Physical restraints make it worse: isometric contraction against restraint generates more heat and more rhabdomyolysis, so sedate instead.
Anticipate the Complications
Rhabdomyolysis with a very high CK, acute kidney injury, hyperkalemia, DIC and respiratory failure.Give aggressive fluids targeting a good urine output and follow CK, potassium, renal function and coagulation serially. These are what kill, rather than the hyperthermia itself.
Plan the Re-Exposure Carefully
After NMS, wait at least 2 weeks after full resolution before restarting an antipsychotic, and choose a lower-potency or atypical agent, titrating slowly. After serotonin syndrome, allow a washout appropriate to the drug, remembering that fluoxetine has a very long half-life and that an MAOI requires a 2-week gap in either direction.Document the reaction prominently, since recurrence risk is real and the next prescriber will not know.
The most common cause of hypercalcemia in hospitalized patients. "Stones, bones, groans, psychiatric moans." PTH will be SUPPRESSED (unlike primary hyperparathyroidism). Treatment is stepwise: fluids → calcitonin (hours) → bisphosphonate (days). Furosemide for hypercalcemia is outdated.
Aggressive IV fluids + calcitonin + bisphosphonate. May need ICU.
🚨 Management
Stepwise Treatment Protocol
Step
Intervention
Onset
Details
Step 1: IV NS
Normal Saline 200–300 mL/hr
Immediate
Most patients are severely volume-depleted from hypercalcemia-induced nephrogenic DI (polyuria + poor PO intake). This alone drops Ca by 1–2 mg/dL. Goal: restore euvolemia and enhance renal calcium excretion.
Step 2: Calcitonin
Calcitonin (Miacalcin) 4 IU/kg SQ/IM q12h
4–6 hours
Bridge therapy -works FAST but tachyphylaxis by 48h (receptors downregulate). Drops Ca by ~1–2 mg/dL. Mild side effect: flushing, nausea. Used while waiting for bisphosphonate to kick in.
Step 3: Bisphosphonate
Zoledronic acid (Zometa) 4 mg IV over 15 min
2–4 DAYS
Definitive treatment. Inhibits osteoclast-mediated bone resorption. Effect lasts weeks. Check Cr first -reduce dose if CrCl < 60. Alternative: pamidronate 60–90 mg IV over 2–4h (slower infusion, may be better in renal impairment).
Step 4 (Refractory)
Denosumab (Xgeva) 120 mg SQ
Days
For bisphosphonate-refractory hypercalcemia. RANKL inhibitor. Works even in renal failure (not renally cleared, unlike bisphosphonates). Dose on days 1, 8, 15, 29, then monthly.
Furosemide (Lasix) for hypercalcemia is OUTDATED. Old teaching was "saline + Lasix." Current evidence: Lasix only if volume overloaded. It does not meaningfully lower calcium and risks further dehydration and electrolyte derangements.
Special Situations
Lymphoma (1,25-vit D mediated):Glucocorticoids (dexamethasone 4 mg IV q6h or equivalent) are effective -they inhibit 1-alpha hydroxylase in tumor cells and decrease 1,25-vit D production.
Multiple myeloma: Bisphosphonates are standard (both for hypercalcemia and skeletal events). Zoledronic acid or pamidronate.
Dialysis: If refractory or anuric, hemodialysis with low-calcium dialysate can rapidly lower calcium.
🧪 Workup
Laboratory Workup
Corrected calcium = measured Ca + 0.8 × (4.0 − albumin). Or check ionized calcium (more accurate, not affected by albumin).
PTH -should be SUPPRESSED (< 20 pg/mL) in malignancy. If PTH is elevated → think primary hyperparathyroidism (even in cancer patients -can coexist).
PTHrP -elevated in humoral hypercalcemia of malignancy (80% of cases). Order if PTH suppressed.
1,25-dihydroxyvitamin D -elevated in lymphoma. Order if PTHrP is normal and PTH is suppressed.
25-hydroxyvitamin D -to rule out exogenous vitamin D toxicity.
Phosphate -low in PTHrP-mediated (PTHrP causes renal phosphate wasting, same as PTH).
BMP -Cr (renal function), K⁺, Mg²⁺.
ECG -shortened QT interval is the classic finding. Also watch for bradycardia, AV block.
SPEP/UPEP -if myeloma suspected.
💊 Medications
Hypercalcemia Medications
Drug
Dose
Onset
Duration
Key Notes
Normal Saline
200–300 mL/hr
Immediate
During infusion
First-line. Volume expansion + calciuresis. Drops Ca ~1–2 mg/dL. Watch for volume overload.
Calcitonin (Miacalcin)
4 IU/kg SQ/IM q12h
4–6 hours
48h (tachyphylaxis)
Bridge only. Drops Ca ~1–2 mg/dL. Safe but temporary. Tachyphylaxis limits use beyond 48h.
Zoledronic acid (Zometa)
4 mg IV over 15 min
2–4 days
Weeks
Definitive treatment. Check CrCl -reduce dose if < 60. Risk: osteonecrosis of jaw (rare), renal toxicity.
Pamidronate
60–90 mg IV over 2–4h
2–4 days
Weeks
Alternative to zoledronic acid. Longer infusion but may be better tolerated in renal impairment.
Denosumab (Xgeva)
120 mg SQ
Days
Weeks
Bisphosphonate-refractory cases. RANKL inhibitor. Works in renal failure. Risk: hypocalcemia, ONJ.
Glucocorticoids
Dexa 4 mg IV q6h
Days
During treatment
Effective for lymphoma and granulomatous disease (1,25-vit D mediated). Not effective for PTHrP-mediated.
📋 On Rounds
Why is PTH suppressed in hypercalcemia of malignancy?
In malignancy-related hypercalcemia, the elevated calcium provides negative feedback to the parathyroid glands via the calcium-sensing receptor (CaSR). Since the hypercalcemia is driven by PTHrP, osteolytic metastases, or tumor-produced 1,25-vit D -NOT by the parathyroid glands -the glands appropriately suppress PTH secretion. This is the key lab distinction: Malignancy → PTH LOW, PTHrP HIGH.
What is tachyphylaxis with calcitonin, and how does it affect your treatment plan?
Tachyphylaxis = diminishing response to a drug after repeated doses. Calcitonin works by inhibiting osteoclast activity and promoting renal calcium excretion. However, calcitonin receptors downregulate within 48 hours of continuous exposure, and the calcium-lowering effect is lost. This is why calcitonin is a bridge therapy only -it buys you 24–48h of calcium lowering while you wait for the bisphosphonate (zoledronic acid)
When would you use denosumab instead of zoledronic acid?
Denosumab (Xgeva) is a RANKL inhibitor (monoclonal antibody) used for hypercalcemia refractory to bisphosphonates. Key advantages: (1) Not renally cleared -safe in renal failure (CrCl < 30), whereas bisphosphonates require dose adjustment or are contraindicated. (2) Bisphosphonate-refractory -if Ca remains elevated after adequate bisphosphonate trial. Disadvantages: (1) Risk of rebound hypercalcemia if discontinued abruptly.
Clinical Examples
📋 Case 1, Hypercalcemia of Malignancy (PTHrP-Mediated)
Patient: 62M with 30-pack-year smoking history. Confusion, polyuria, constipation. Ca 15.2, PTH < 5, PTHrP 14.8 pmol/L (elevated). CT chest: 5 cm RUL mass with hilar LAD. Cr 2.1.
Key findings: Severe hypercalcemia of malignancy via PTHrP from probable squamous cell lung cancer. Suppressed PTH confirms non-parathyroid etiology. Dehydration worsening renal function.
Management:
NS 200-300 mL/hr (aggressive rehydration, these patients are profoundly volume-depleted)
Calcitonin 4 IU/kg SQ q12h (bridge, works within hours but tachyphylaxis by 48h)
Zoledronic acid 4 mg IV over 15 min (definitive, onset 2-4 days, lasts 2-4 weeks)
No furosemide unless volume overloaded (old teaching of "lasix for hypercalcemia" is outdated and harmful in dehydrated patients)
Oncology consult for biopsy and staging of lung mass
Teaching point: Calcitonin is a bridge, not a treatment. Its effect wears off in 48h due to receptor tachyphylaxis. Zoledronic acid is the definitive agent but takes 2-4 days, hence the bridge strategy.
📋 Case 2, Severe Hypercalcemia with Renal Failure
Patient: 71F with metastatic breast cancer. Ca 17.8, Cr 4.2 (baseline 1.0), AMS. PTH < 3. No urine output × 6h despite 2L NS bolus. ECG: short QT.
Key findings: Life-threatening hypercalcemia with oliguric AKI. Bisphosphonates relatively contraindicated at CrCl < 30. Need alternative approach.
Management:
Continue aggressive IVF, target UOP > 200 mL/hr if achievable
Calcitonin 4 IU/kg SQ q12h (immediate bridge)
Denosumab 120 mg SQ (not renally cleared, safe in renal failure, preferred over zoledronic acid here)
If refractory: emergent hemodialysis with low-calcium dialysate (can drop Ca 3-4 mg/dL per session)
Telemetry monitoring, QT shortening, arrhythmia risk at Ca > 14
Teaching point: Denosumab is the rescue agent when bisphosphonates are contraindicated (renal failure) or have failed. Key risk: rebound hypercalcemia if stopped abruptly, always plan for ongoing dosing or transition.
📋 Case 3, Granulomatous Disease Hypercalcemia
Patient: 38F with known sarcoidosis. Ca 12.6, PTH 6 (suppressed), PTHrP normal, 1,25-dihydroxy vitamin D 88 pg/mL (elevated), 25-OH vitamin D 22 (normal). Bilateral hilar LAD on CXR.
Key findings: Granulomatous hypercalcemia, activated macrophages in granulomas express 1-alpha-hydroxylase, converting 25-OH vitamin D → 1,25-dihydroxy vitamin D (calcitriol) autonomously. Not PTH-driven.
Management:
IV hydration (NS 150-200 mL/hr)
Prednisone 20-40 mg daily (first-line, glucocorticoids inhibit 1-alpha-hydroxylase in macrophages)
Expect calcium normalization within 3-5 days of steroids
Avoid vitamin D supplementation and excessive sun exposure (fuel the pathway)
Treat underlying sarcoidosis per pulmonology
Teaching point: Granulomatous hypercalcemia (sarcoidosis, TB, fungal) responds to glucocorticoids because steroids suppress macrophage 1-alpha-hydroxylase. This is the one form of hypercalcemia where steroids are first-line, not bisphosphonates.
Monitoring Parameters
Parameter
Frequency
Target / Action
Ionized calcium or corrected Ca
q6–8h until stable
Trend toward normalization. Recheck 2–4 days after bisphosphonate.
BMP (Cr, K⁺, Mg²⁺, PO₄)
q12h initially
Cr for AKI/renal recovery. Watch for hypokalemia, hypomagnesemia, hypophosphatemia with fluids.
Fluid balance / I&Os
Strict
Maintain euvolemia. Aggressive IVF but watch for volume overload (especially if cardiac history).
ECG
Admission + PRN
Shortened QT, bradycardia, AV block.
Mental status
q shift
Improvement in confusion/lethargy as calcium normalizes.
Monitoring Parameters
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h ICU
HR, BP, RR, SpO₂, Temp -notify for significant deviations
Labs (BMP, CBC)
Daily AM or as indicated
Trend Cr, K⁺, WBC, Hgb -adjust treatment based on trajectory
Disease-specific markers
Per clinical context
See Overview and Management tabs for condition-specific targets
I&Os
Strict if volume-sensitive
UOP ≥ 0.5 mL/kg/hr. Net fluid balance guides diuresis or resuscitation.
Telemetry
Continuous if indicated
Arrhythmia detection. Discontinue when no longer indicated (reduces alarm fatigue).
Clinical response
Each assessment
Symptom improvement, functional status, appetite, mental status -the exam matters more than labs
Don't just order labs -act on them. Every lab should have a clear clinical question. If you wouldn't change management based on the result, don't order it.
⚡ Summary
Hypercalcemia of Malignancy -Key Points
Recognize It
Stones, bones, groans and psychiatric moans: kidney stones and polyuria, bone pain, constipation, nausea and abdominal pain, and confusion progressing to coma. It is the commonest cause of hypercalcemia in hospitalized patients, and the severity of symptoms depends on how fast it rose as much as on the number.
Correct the Number Before Acting On It
Add 0.8 mg/dL for every 1 g/dL the albumin sits below 4, or measure ionized calcium directly. Cancer patients are frequently hypoalbuminemic, so an uncorrected total calcium understates the true level and delays treatment.
A Suppressed PTH Is the Discriminator
PTH is suppressed in malignancy and inappropriately normal or high in primary hyperparathyroidism. That single test splits the differential. Then check PTHrP and 1,25-dihydroxyvitamin D to identify which malignant mechanism is operating.
Know Which Mechanism You Are Treating
PTHrP-mediated humoral hypercalcemia (about 80%), classically squamous cell carcinoma, renal cell and breast. Local osteolysis from bone metastases and myeloma. Calcitriol-mediated, from lymphoma and granulomatous disease, where 1-alpha-hydroxylase in the tumor activates vitamin D. The calcitriol type is the one that responds to steroids, and it is the one where vitamin D supplementation makes things worse.
Fluids First, and Generously
Isotonic saline, typically 200 to 300 mL/h initially, titrated to a urine output of 100 to 150 mL/h. These patients are profoundly volume-depleted from the calcium-induced nephrogenic diabetes insipidus, and restoring glomerular filtration is what starts the calcium falling within hours.
Calcitonin Bridges, Bisphosphonate Treats
Calcitonin 4 units/kg SC or IM q12h works within 4 to 6 h but tachyphylaxis develops in 48 h, so it is a bridge and nothing more. Zoledronic acid 4 mg IV is the definitive agent but takes 2 to 4 days to work, which is exactly the gap calcitonin covers. Give both at the start rather than in sequence.
Furosemide Is Outdated
The old teaching of saline plus Lasix is wrong.Loop diuretics do not meaningfully lower calcium and they worsen the dehydration that is driving it.Use them only if the patient becomes volume overloaded during fluid resuscitation, and then for that reason, not for the calcium.
Match the Refractory Options to the Situation
Denosumab when renal function precludes a bisphosphonate, or for bisphosphonate-refractory hypercalcemia; it is not renally cleared, but it can cause prolonged hypocalcemia. Steroids for calcitriol-mediated hypercalcemia (lymphoma, sarcoidosis). Dialysis for severe, refractory or oliguric cases.Treat the cancer, since nothing else is durable, and recognize what the diagnosis signals: hypercalcemia of malignancy carries a poor prognosis and is a prompt for a goals-of-care conversation.
RoundsRx Infographic Series · #86 · Renal & Metabolic · PDF 151 KB
Text version
HEME/ONC · One Pager
Hypercalcemia of Malignancy
The tumor drives calcium up and the parathyroids appropriately shut off, so PTH is SUPPRESSED; treat in sequence, fluids for volume, calcitonin as the fast bridge, a bisphosphonate as the definitive agent.
🧪 Mechanisms, Most Common First
PTHrP, humoral (~80%), in squamous cell carcinomas (lung, head and neck), renal cell, breast, bladder. PTHrP elevated, PTH suppressed, phosphate LOW, because PTHrP causes renal phosphate wasting exactly as PTH does.
Osteolytic metastases (~20%), in breast cancer and multiple myeloma. PTHrP is normal here: calcium comes from local cytokine release (RANKL, IL-6) dissolving bone directly, which is why bone-directed therapy is the answer.
1,25-dihydroxyvitamin D mediated (< 1%), in lymphoma (Hodgkin and non-Hodgkin). Tumor cells make their own 1-alpha hydroxylase, so 1,25-vitamin D is elevated. This is the subtype that responds to steroids.
Ectopic PTH (very rare), ovarian and small cell lung. PTH is elevated because the tumor itself secretes it, the one malignant mechanism that breaks the "PTH is suppressed" rule.
Why the mechanism matters: it decides whether the definitive drug is a bisphosphonate, denosumab, or a glucocorticoid.
⚡ Presentation & Severity
Stones: nephrolithiasis, nephrocalcinosis, and polyuria from a nephrogenic DI (calcium impairs the renal response to ADH).
Bones: bone pain, pathologic fractures, osteoporosis.
Cardiac:shortened QT interval (the classic ECG finding), bradycardia, AV block when severe.
The vicious cycle: polyuria causes dehydration, dehydration reduces renal calcium clearance, calcium climbs further. This is why volume comes first in treatment.
Mild, corrected Ca 10.5-12.0: oral hydration, monitor, treat the underlying malignancy.
Moderate, 12.0-14.0: IV fluids ± calcitonin plus a bisphosphonate.
Severe, > 14.0 or symptomatic: aggressive IV fluids plus calcitonin plus bisphosphonate; may need ICU.
🚨 Management, Step by Step
1
Normal saline 200-300 mL/hr, effect immediate. These patients are severely volume-depleted from hypercalcemia-induced nephrogenic DI plus poor oral intake. Restoring euvolemia enhances renal calcium excretion and drops calcium 1-2 mg/dL by itself, which is why nothing else works properly until this is done.
2
Calcitonin 4 IU/kg SQ or IM q12h, onset 4-6 hours. The only agent that works fast, so it bridges the gap while the bisphosphonate takes effect. Drops calcium ~1-2 mg/dL. Tachyphylaxis by 48h as receptors downregulate, so it is a bridge and never the plan.
3
Zoledronic acid 4 mg IV over 15 min, onset 2-4 DAYS, lasts weeks. The definitive treatment: it inhibits osteoclast-mediated bone resorption, which is the actual source of the calcium. Check creatinine first and reduce the dose if CrCl < 60. Alternative: pamidronate 60-90 mg IV over 2-4h, a slower infusion that may be better tolerated in renal impairment.
4
Refractory or renal failure: denosumab 120 mg SQ, onset days. A RANKL inhibitor that works even in renal failure because it is not renally cleared, unlike bisphosphonates. Dose on days 1, 8, 15, 29, then monthly. Plan continued dosing, since abrupt discontinuation causes rebound hypercalcemia.
5
Do NOT give furosemide reflexively. The old "saline plus Lasix" teaching is outdated: it does not meaningfully lower calcium and worsens the dehydration that is driving the problem. Use it only if the patient is genuinely volume overloaded.
💊 Key Drugs
Normal saline200-300 mL/hr. First-line: volume expansion plus calciuresis drops Ca ~1-2 mg/dL. Watch for volume overload in cardiac patients.
Calcitonin (Miacalcin)4 IU/kg SQ or IM q12h. Onset 4-6 h, useful for only ~48h before tachyphylaxis. Drops Ca ~1-2 mg/dL. Mild flushing and nausea.
Zoledronic acid (Zometa)4 mg IV over 15 min. Onset 2-4 days, lasts weeks. Definitive agent. Check CrCl and reduce if < 60. Risks: renal toxicity, rare osteonecrosis of the jaw.
Pamidronate60-90 mg IV over 2-4h. Same onset and duration as zoledronic acid; the longer infusion may be better tolerated in renal impairment.
Denosumab (Xgeva)120 mg SQ. RANKL inhibitor for bisphosphonate-refractory disease or renal failure, since it is not renally cleared. Risks: hypocalcemia, osteonecrosis of the jaw, rebound hypercalcemia if stopped.
GlucocorticoidsDexamethasone 4 mg IV q6h. Works only in the 1,25-vitamin D mediated forms (lymphoma, granulomatous disease) by inhibiting 1-alpha hydroxylase. Not effective for PTHrP-mediated disease.
📊 Monitoring
Ionized or corrected calcium q6-8h until stable, then recheck 2-4 days after the bisphosphonate, which is when it actually starts working and when you decide whether denosumab is needed.
BMP q12h initially: creatinine for AKI and renal recovery, and watch for the hypokalemia, hypomagnesemia, and hypophosphatemia that aggressive fluids produce.
Strict intake and output. You are deliberately running fluids hard, so volume overload is the predictable complication, especially with cardiac history.
ECG on admission and PRN: shortened QT, bradycardia, and AV block are the arrhythmia signals, and the risk rises above a calcium of 14.
Mental status each shift. Clearing confusion is the clinical endpoint that tells you the number is translating into benefit.
Corrected calcium = measured Ca + 0.8 × (4.0 − albumin), or use ionized calcium, which albumin does not distort.
⚠️ Pitfalls
Reaching for furosemide. Outdated teaching: it does not meaningfully lower calcium and it deepens the dehydration that caused the hypercalcemia. Only for true volume overload.
Treating calcitonin as the therapy. Tachyphylaxis at 48h means the calcium rebounds unless a bisphosphonate or denosumab was started alongside it on day one.
Giving zoledronic acid without checking renal function. Reduce the dose if CrCl < 60, and reach for denosumab instead when the kidney is failing.
Stopping denosumab abruptly. Rebound hypercalcemia follows; always plan ongoing dosing or a deliberate transition.
Assuming every hypercalcemia in a cancer patient is paraneoplastic. If PTH is elevated, think primary hyperparathyroidism, which can coexist with malignancy and needs an entirely different workup.
Giving steroids for PTHrP-mediated hypercalcemia. They only work when the driver is tumor or macrophage 1,25-vitamin D production.
Expecting a bisphosphonate to work overnight. Onset is 2-4 days, which is the entire reason the calcitonin bridge exists.
🏥 Special Situations
Lymphoma (1,25-vitamin D mediated): glucocorticoids, dexamethasone 4 mg IV q6h or equivalent, because they inhibit 1-alpha hydroxylase in the tumor cells and shut off calcitriol production at the source.
Granulomatous disease (sarcoidosis, TB, fungal): prednisone 20-40 mg daily is first-line, since activated macrophages in granulomas autonomously convert 25-OH vitamin D to calcitriol. Expect normalization within 3-5 days, and avoid vitamin D supplements and heavy sun exposure, which fuel the pathway. This is the one form of hypercalcemia where steroids beat bisphosphonates.
Multiple myeloma: bisphosphonates are standard, treating both the hypercalcemia and the skeletal-related events. Zoledronic acid or pamidronate.
Refractory or anuric: hemodialysis with low-calcium dialysate rapidly lowers calcium, dropping it 3-4 mg/dL per session when fluids are not an option.
🔬 Workup, in Sequence
Corrected or ionized calcium first, to confirm the calcium is genuinely high and not an albumin artifact.
PTH: should be SUPPRESSED (< 20 pg/mL) in malignancy, because high calcium feeds back on the parathyroid calcium-sensing receptor and the glands respond appropriately. An elevated PTH points to primary hyperparathyroidism instead.
PTHrP next if PTH is suppressed, since it is the mechanism in 80% of cases.
1,25-dihydroxyvitamin D if PTHrP is normal and PTH is suppressed, which identifies the lymphoma and granulomatous group that needs steroids.
25-hydroxyvitamin D to rule out exogenous vitamin D toxicity as the cause.
Phosphate: low in PTHrP-mediated disease, because PTHrP wastes phosphate at the kidney just as PTH does.
BMP for creatinine, K⁺, and Mg²⁺; ECG for the shortened QT; SPEP/UPEP if myeloma is suspected.
Preoperative risk assessment, medication management around surgery, and co-management of medical issues in surgical patients. Know when to bridge anticoagulation (hint: usually don't), when to order a stress test (hint: rarely), and which medications to hold or continue.
🔍 Overview
Cardiac Risk Assessment
Revised Cardiac Risk Index (RCRI / Lee Index) -6 independent predictors of major cardiac events after non-cardiac surgery Lee, Circulation 1999:
High-risk surgery (intraperitoneal, intrathoracic, suprainguinal vascular)
History of ischemic heart disease
History of heart failure
History of cerebrovascular disease (stroke/TIA)
Diabetes on insulin
Creatinine > 2.0 mg/dL
RCRI Score
Risk of Major Cardiac Event
Approach
0
~3.9%
Low risk -proceed to surgery
1
~6.0%
Low-intermediate -proceed if good functional capacity (≥ 4 METs)
2
~10.1%
Intermediate -consider stress testing if poor functional capacity AND will change management
≥ 3
~15%
High risk -stress testing if will change management, cardiology consult
Functional Capacity
≥ 4 METs = adequate functional capacity (low cardiac risk regardless of RCRI). 4 METs ≈ climbing one flight of stairs, walking on level ground at 4 mph, doing heavy housework (scrubbing floors, moving furniture). If a patient can do these activities without chest pain or dyspnea, they can likely tolerate surgery without further cardiac testing.
🚨 Management
Cardiac Medication Management
NEVER start a new beta-blocker within 24h of surgery. The POISE trial showed that starting metoprolol perioperatively increased stroke and death despite reducing MI. Only continue beta-blockers if the patient is already on one. POISE, NEJM 2008
Beta-blockers: CONTINUE if already on one (withdrawal can cause rebound tachycardia and ischemia). Do NOT start new ones perioperatively.
Statins: CONTINUE perioperatively -associated with reduced cardiac events and mortality.
ACE inhibitors/ARBs: Generally HOLD morning of surgery (risk of refractory hypotension with anesthesia). Resume postop when tolerating PO.
Anticoagulation Management
Agent
When to Stop
Bridge?
Key Notes
Warfarin
5 days before
Bridge with LMWH ONLY if HIGH thrombotic risk: mechanical mitral valve, recent VTE (< 3 months), CHA₂DS₂-VASc ≥ 7
BRIDGE Trial, NEJM 2015 -most AF patients do NOT need bridging. Bridging increases bleeding without reducing thrombosis.
DOACs (apixaban, rivaroxaban)
2–3 days before (longer if CrCl < 50 for dabigatran)
No bridging needed
Short half-lives. If urgent reversal needed: idarucizumab (dabigatran), andexanet alfa (Xa inhibitors), or PCC.
Aspirin
Continue for most surgeries
N/A
Exception: intracranial surgery -hold 7 days before. For most non-cardiac surgery, continuing aspirin is safe.
P2Y12 inhibitors (clopidogrel, ticagrelor)
Clopidogrel: 5 days. Ticagrelor: 3–5 days.
No
If patient has recent coronary stent (< 6 weeks BMS, < 6 months DES), surgery should be delayed if possible. Cardiology consult.
🔄 Updated Practice: Old teaching: stop anticoagulation and bridge all AF patients with heparin before surgery. Current practice: the BRIDGE trial (NEJM 2015) showed that most AF patients do NOT need bridging, no-bridging was non-inferior for thromboembolism and caused significantly less major bleeding. Bridge only for the highest-risk patients: mechanical mitral valve, recent VTE (<3 months), or very high CHA₂DS₂-VASc (≥7). When in doubt, don't bridge.
Diabetes Management
Metformin: HOLD day of surgery (risk of lactic acidosis with contrast or hypoperfusion). Resume when eating and renal function stable.
SGLT2 inhibitors: HOLD 3–4 days before surgery (risk of euglycemic DKA -normal glucose but elevated ketones + anion gap). FDA Safety Communication, 2020
Basal insulin: Reduce to 50–80% of usual dose the night before surgery. Do NOT hold completely (risk of DKA in type 1).
Bolus/prandial insulin: HOLD the morning of surgery (patient is NPO).
Oral agents (sulfonylureas, TZDs): HOLD morning of surgery.
GLP-1 agonists (semaglutide, liraglutide): May hold -risk of delayed gastric emptying and aspiration. ASA recommends holding day of surgery for daily formulations, 1 week for weekly formulations.
Pulmonary Risk Reduction
Updated Practice: Old teaching -get preop PFTs on everyone. WRONG -routine preop PFTs do NOT predict postoperative pulmonary complications and are NOT recommended. Clinical assessment (history, exam, functional capacity) is sufficient.
Incentive spirometry: Start preop and continue postop -reduces atelectasis and pneumonia.
Smoking cessation: Ideally ≥ 8 weeks before surgery if possible. Even 24–48h of cessation reduces CO levels and improves O₂ delivery.
Avoid NG tube if possible (increases aspiration risk).
Early mobilization postop -most important intervention for preventing pulmonary complications.
🧪 Workup
Preoperative Testing
Only order tests that will change management. Routine "preop labs" without indication increase cost and false positives without improving outcomes.
ECG: If RCRI ≥ 1, known cardiac disease, or symptoms. Not needed for low-risk patients undergoing low-risk surgery.
CBC: If anticipated blood loss, anemia symptoms, or liver/renal disease.
BMP: If renal disease, diabetes, diuretic use, or major surgery with expected fluid shifts.
Coags (PT/INR): If on anticoagulants, liver disease, or bleeding history.
Type & screen: If blood loss anticipated.
Glucose: If diabetic -day-of-surgery glucose management.
Pregnancy test: All women of childbearing age (many institutions mandate this).
Stress test: Only if it will change management AND the patient has poor functional capacity (< 4 METs) AND elevated RCRI (≥ 2). Do NOT get routine preop stress tests.
PFTs: NOT routinely indicated. Only if new/unexplained dyspnea or for lung resection surgery.
CXR: NOT routinely indicated. Only if acute pulmonary symptoms or significant cardiopulmonary disease.
Risk of refractory intraop hypotension. Resume when tolerating PO and hemodynamically stable.
Warfarin
STOP 5 days before
Bridge only for HIGH thrombotic risk (mechanical mitral valve, recent VTE <3mo).
DOACs
STOP 2–3 days before
No bridging needed. Extend to 4–5 days for dabigatran if CrCl < 50.
Aspirin
CONTINUE (most cases)
Hold for intracranial surgery. Otherwise, continue.
Metformin
HOLD day of surgery
Lactic acidosis risk with hypoperfusion/contrast.
SGLT2 inhibitors
HOLD 3–4 days before
Euglycemic DKA risk perioperatively.
Basal insulin
Reduce to 50–80% night before
Prevent hypoglycemia while NPO. Do NOT hold entirely in type 1.
Sulfonylureas
HOLD morning of surgery
Hypoglycemia risk while NPO.
GLP-1 agonists
HOLD (daily: day of; weekly: 1 wk)
Delayed gastric emptying → aspiration risk with anesthesia.
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When do you bridge anticoagulation for a patient on warfarin undergoing elective surgery?
Bridge with LMWH ONLY for patients at HIGH thrombotic risk: (1) Mechanical mitral valve (or any mechanical valve with additional risk factors), (2) Recent VTE within 3 months, (3) Very high CHA₂DS₂-VASc (≥ 7). For the vast majority of AF patients, do NOT bridge. The landmark BRIDGE trial (NEJM 2015) showed that bridging in AF patients did not reduce thromboembolism but significantly increased major bleeding.
What is the RCRI (Revised Cardiac Risk Index)?
The RCRI (Lee Index) is the most widely used tool for preoperative cardiac risk stratification. It has 6 independent predictors (1 point each): (1) High-risk surgery (intraperitoneal, intrathoracic, suprainguinal vascular), (2) Ischemic heart disease, (3) Heart failure, (4) Cerebrovascular disease, (5) Diabetes on insulin, (6) Cr > 2.0. Score interpretation: 0 = ~3.9% risk of major cardiac event, 1 = ~6%, 2 = ~10%, ≥3 = ~15%.
Why should you NOT start new beta-blockers perioperatively?
The POISE trial (NEJM 2008) randomized patients to extended-release metoprolol vs placebo started within 2–4h before surgery. Results: metoprolol reduced MI (4.2% vs 5.7%) BUT doubled the rate of stroke (1.0% vs 0.5%) and increased overall mortality (3.1% vs 2.3%). The mechanism: beta-blockers cause perioperative hypotension and bradycardia → cerebral hypoperfusion → stroke.
When should you get a preoperative stress test?
Preop stress tests are indicated only when ALL THREE conditions are met: (1) The result will change management (i.e., you would cancel or modify the surgery based on the result). (2) The patient has poor functional capacity (< 4 METs -cannot climb one flight of stairs). (3) The patient has elevated cardiac risk (RCRI ≥ 2 or known significant cardiac disease). If any of these is missing, a stress test is NOT indicated.
Postoperative Monitoring
Parameter
Frequency
Target / Action
Vitals
q4h floor, q1–2h PACU
Watch for hypotension (bleeding, sepsis), tachycardia (pain, PE, bleeding), fever.
10 breaths q1h. Prevents atelectasis and postop pneumonia.
⚡ Summary
Perioperative Medicine -Key Points
Assess Risk With RCRI Plus Function
Revised Cardiac Risk Index: high-risk surgery, ischemic heart disease, heart failure, cerebrovascular disease, insulin-treated diabetes, creatinine above 2.Combine it with functional capacity: a patient who can climb two flights of stairs, roughly 4 METs, has a low event rate regardless of the checklist. Poor or unassessable functional capacity is what should trigger further testing, not the score alone.
Do Not Start a Beta Blocker Before Surgery
POISE showed starting perioperative metoprolol reduced myocardial infarction but increased stroke and death.Continue a beta blocker in a patient already taking one, since abrupt withdrawal causes rebound ischemia, but never start one within 24 h of the operation.
Most AF Patients Do Not Need Bridging
BRIDGE showed no-bridging was non-inferior for thromboembolism and caused significantly less major bleeding.Reserve bridging for genuinely high thrombotic risk: mechanical mitral valve, recent stroke or VTE, or antiphospholipid syndrome. Stop DOACs 24 to 48 h before, longer with renal impairment, and no bridging is needed for them at all given their short half-life.
Skip Routine Preoperative Testing
Routine PFTs do not predict postoperative pulmonary complications and are not recommended; clinical assessment is sufficient. The same applies to routine chest films, ECGs in low-risk patients and broad laboratory panels. Order a test only if the result would change the anesthetic or the operation; incidental abnormalities cause delay and cascade without benefit.
Manage Antiplatelets Around Stents
Delay elective surgery for at least 6 months after a drug-eluting stent and 1 month after a bare metal stent.Continue aspirin through most operations where possible.Premature interruption of dual antiplatelet therapy causes stent thrombosis, which carries very high mortality, so the timing conversation is with cardiology and surgery together, not unilaterally.
Reduce Pulmonary Risk With What Actually Works
Smoking cessation, ideally at least 4 to 8 weeks before, incentive spirometry, early mobilization, lung expansion techniques and good pain control, plus screening for and treating obstructive sleep apnea. Upper abdominal and thoracic surgery, long operations and poor functional status are the main risk factors, and they are what should prompt these measures.
Get the Diabetes Medications Right
Hold metformin on the day of surgery, hold SGLT2 inhibitors 3 to 4 days before because of euglycemic DKA risk, and hold sulfonylureas while NPO.Continue basal insulin, usually dose-reduced; never stop it entirely in type 1, since that causes DKA within hours. Target 100 to 180 mg/dL perioperatively, and do not postpone surgery on A1c alone.
Plan the Postoperative Watch
Myocardial injury after non-cardiac surgery is common and usually silent, so a rising troponin in a high-risk patient matters even without chest pain. Also anticipate delirium in the elderly (minimize anticholinergics and benzodiazepines), postoperative ileus, VTE prophylaxis timing around neuraxial anesthesia, and adequate multimodal analgesia to allow mobilization.
Non-caseating granulomatous disease affecting multiple organs. Lungs involved in 90%. Bilateral hilar lymphadenopathy on CXR is the hallmark. Young adults, especially African Americans. Lofgren syndrome = excellent prognosis.
🔍 Overview
Overview
Sarcoidosis is a systemic granulomatous disease of unknown etiology characterized by non-caseating granulomas in affected organs. The lungs are involved in ~90% of cases. Other commonly affected organs: skin (erythema nodosum, lupus pernio), eyes (anterior uveitis), liver (granulomatous hepatitis), heart (conduction abnormalities, cardiomyopathy), and nervous system (cranial nerve palsies, especially CN VII). Epidemiology: peaks at age 25-35, higher incidence and more severe disease in African Americans and Scandinavians.
Lofgren Syndrome
A specific acute presentation with an excellent prognosis (>90% spontaneous resolution): bilateral hilar lymphadenopathy + erythema nodosum + polyarthralgia + fever. So characteristic that biopsy is often NOT required for diagnosis. More common in young women.
Scadding CXR Staging
Stage 0 -Normal CXR
Stage I -Bilateral hilar lymphadenopathy (BHL) alone. ~60-80% spontaneous remission.
Stage II -BHL + pulmonary infiltrates. ~50-60% remission.
Stage III -Pulmonary infiltrates WITHOUT lymphadenopathy. ~30% remission.
Stage IV -Pulmonary fibrosis. Irreversible. Poor prognosis.
🚨 Management
Treatment Approach
Many patients need NO treatment -sarcoidosis is self-resolving in a large proportion of cases, especially Stage I and Lofgren syndrome. Observation alone is appropriate for asymptomatic patients with stable disease.
Renal involvement -nephrocalcinosis, nephrolithiasis from hypercalciuria
First-Line Therapy
Prednisone20-40 mg daily x 4-6 weeks, then slow taper over 6-12 months. Total treatment duration typically 12+ months. Relapse rate is high (~30-50%) when steroids are tapered. NSAIDs can be used for mild arthralgia and erythema nodosum.
Steroid-Sparing Agents
Consider when: unable to taper below prednisone 10 mg/day, steroid side effects, or relapse on taper.
Methotrexate (Trexall) -most commonly used steroid-sparing agent. 10-15 mg weekly. Supplement with folic acid.
Azathioprine (Imuran) -alternative to MTX. 50-200 mg daily. Check TPMT before starting.
Mycophenolate (CellCept) -500-1500 mg BID. Used for refractory disease.
Refractory Disease
Infliximab (Remicade) -anti-TNF-alpha. Reserved for severe disease failing conventional therapy. Evidence strongest for lupus pernio and neurosarcoidosis.
🧪 Workup
Diagnostic Workup
CXR -Scadding staging (I-IV). Bilateral hilar lymphadenopathy is classic.
CT chest -better characterization of parenchymal disease, lymphadenopathy pattern
PFTs -restrictive pattern (decreased FVC, decreased DLCO). Obstructive pattern also possible with endobronchial involvement.
ACE level -elevated in ~60% but NOT diagnostic. Neither sensitive nor specific (see alert below).
Calcium -check serum calcium (hypercalcemia from granulomatous 1,25-vitamin D production)
24-hour urine calcium -hypercalciuria may be present even with normal serum calcium
ECG -screen for heart block (PR prolongation, bundle branch block). If abnormal, consider cardiac MRI or PET.
Ophthalmology exam -screen for uveitis (anterior > posterior), even if asymptomatic
Biopsy of accessible tissue -lung (transbronchial), skin, lymph node. REQUIRED for definitive diagnosis.
ACE level is NOT a good diagnostic test for sarcoidosis. Sensitivity ~60%, specificity poor. Many false positives and false negatives. ACE inhibitors lower it (false negative), diabetes can raise it (false positive). Diagnosis requires tissue biopsy showing non-caseating granulomas PLUS exclusion of other causes (TB, fungal infection, lymphoma, berylliosis).
💊 Medications
Medications
Drug
Dose
Route
Notes
Prednisone 1ST LINE
20-40 mg daily x 4-6 wk, then taper over 6-12 months
PO
Start at higher dose for severe organ involvement (cardiac, neuro). Monitor glucose, BP, bone density.
Methotrexate (Trexall)
10-15 mg weekly
PO/SQ
Most common steroid-sparing agent. Add folic acid 1 mg daily. Monitor LFTs, CBC q4-8 weeks. Avoid in pregnancy (teratogenic). Vorselaars, Chest 2013
Alternative steroid-sparing. GI side effects common. Monitor CBC.
Infliximab (Remicade)
3-5 mg/kg IV at weeks 0, 2, 6, then q4-8 weeks
IV
For refractory disease. Screen for TB before starting (anti-TNF reactivates latent TB). Baughman, AJRCCM 2006
Hydroxychloroquine
200-400 mg daily
PO
Useful for skin sarcoidosis, hypercalcemia, and fatigue. Annual eye exams for retinal toxicity.
🏥 Rounds
Pimp Questions
❓ Why is ACE level a poor diagnostic test for sarcoidosis?
ACE is produced by epithelioid cells in granulomas. However, it has sensitivity of only ~60% and poor specificity. ACE inhibitors lower the level (false negative), while diabetes, hyperthyroidism, and other granulomatous diseases can raise it (false positive). It should NEVER be used as a sole diagnostic criterion. Diagnosis requires tissue biopsy + exclusion of other causes.
❓ What is Lofgren syndrome and why is it important?
Lofgren syndrome is an acute presentation of sarcoidosis with the triad of: (1) bilateral hilar lymphadenopathy, (2) erythema nodosum, (3) polyarthralgia, often with fever. It has an excellent prognosis (>90% spontaneous resolution) and is so characteristic that biopsy is often not required for diagnosis. Treatment is usually supportive (NSAIDs for symptoms).
❓ How does sarcoidosis cause hypercalcemia?
Activated macrophages within sarcoid granulomas express 1-alpha-hydroxylase, which converts 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D (calcitriol). This extra-renal production is NOT regulated by PTH, leading to increased intestinal calcium absorption and hypercalcemia. Treatment: corticosteroids suppress macrophage activity. PTH is appropriately suppressed (unlike primary hyperparathyroidism).
❓ What cardiac manifestations should you screen for in sarcoidosis?
Cardiac sarcoidosis can cause: (1) conduction abnormalities -AV block (most common), bundle branch block, (2) ventricular arrhythmias -VT, sudden cardiac death, (3) cardiomyopathy -dilated or restrictive. Screen all patients with an ECG. If abnormal or symptomatic, pursue cardiac MRI (late gadolinium enhancement) or FDG-PET. Cardiac involvement is a leading cause of death in sarcoidosis.
❓ When do you NOT need a biopsy for sarcoidosis diagnosis?
Biopsy may be deferred in two scenarios: (1) Lofgren syndrome -the classic triad of bilateral hilar LAD + erythema nodosum + polyarthralgia is so specific that it is considered virtually diagnostic, (2) Asymptomatic bilateral hilar lymphadenopathy in a young patient with a classic CXR pattern and no concerning features for lymphoma or infection -though many clinicians still prefer biopsy confirmation.
Clinical Examples
📋 Case 1, Stage II Sarcoidosis with Multisystem Disease
Patient: 34-year-old African American woman with 3 months of dry cough, dyspnea, and painful shin nodules. Blurry vision OS.
Biopsy NOT required, Lofgren syndrome is clinically diagnostic
> 90% spontaneous resolution within 2 years
NSAIDs for symptoms. Low-dose prednisone only if refractory.
Follow-up CXR in 3-6 months to confirm resolution
Teaching point: Lofgren syndrome has the best prognosis in sarcoidosis. Recognize the triad. Rarely needs immunosuppression.
📋 Case 3, Cardiac Sarcoidosis
Patient: 42-year-old man with known pulmonary sarcoidosis presenting with palpitations and near-syncope. ECG: new complete heart block.
Key findings: Cardiac MRI: late gadolinium enhancement in basal septum. LVEF 40% (was 55%). FDG-PET: active myocardial inflammation. No CAD on angiography.
Management:
Temporary pacing wire; evaluate for permanent pacemaker/ICD
Prednisone 40-60 mg daily for active cardiac sarcoidosis
Steroid-sparing agent (methotrexate or mycophenolate)
ICD if LVEF ≤ 35% or sustained VT
Guideline-directed HF therapy
Teaching point: Cardiac sarcoidosis is a leading cause of death. Screen ALL sarcoidosis patients with ECG. New AV block or unexplained cardiomyopathy → cardiac MRI or FDG-PET.
Sample Presentation
Ms. Davis is a 34-year-old African American woman presenting with 3 months of dry cough, progressive dyspnea on exertion, and bilateral ankle swelling. She also notes painful red bumps on her shins and bilateral ankle pain. CXR shows bilateral hilar lymphadenopathy with diffuse reticular opacities (Stage II). PFTs: FVC 65% predicted, DLCO 58% predicted. Labs: calcium 11.2, ACE level 85 (elevated), LFTs mildly elevated. Ophtho exam: anterior uveitis OS. Transbronchial biopsy: non-caseating granulomas. AFB and fungal stains negative.
Key Points: Classic Stage II sarcoidosis with multisystem involvement (lungs, skin -erythema nodosum, eyes -uveitis, liver, hypercalcemia). Treatment indicated given progressive pulmonary disease and hypercalcemia. Start prednisone 40 mg daily. Plan for steroid-sparing agent (MTX) given likely need for prolonged therapy.
Monitoring
PFTs -repeat every 3-6 months while on treatment. FVC and DLCO most useful for tracking disease activity.
CXR or CT chest -every 6-12 months depending on disease severity.
Serum calcium and 24h urine calcium -monitor for hypercalcemia/hypercalciuria, especially when tapering steroids.
Ophthalmology -annual screening even if asymptomatic. More frequent if active uveitis.
ECG -annual. Low threshold for cardiac MRI or PET if new symptoms (palpitations, syncope, dyspnea).
LFTs -monitor for hepatic sarcoidosis and drug toxicity (MTX, azathioprine).
CBC -for steroid-sparing drug monitoring (MTX, azathioprine, mycophenolate).
Bone density (DEXA) -if on prolonged steroids (>3 months prednisone >= 5 mg/day).
ACE level -some clinicians follow trends, but NOT useful for diagnosis or as sole marker of disease activity.
📋 Summary
Summary
Recognize It
Non-caseating granulomas in multiple organs, with lungs involved in about 90%. Bilateral hilar lymphadenopathy on chest x-ray is the hallmark. Typically young adults, with higher incidence and more severe disease in African Americans.
Lofgren Syndrome Needs No Biopsy
Erythema nodosum, bilateral hilar lymphadenopathy, arthralgia and fever.The constellation is diagnostic on its own, and the prognosis is excellent with spontaneous remission in most patients, so the treatment is NSAIDs and observation rather than steroids.
Scadding Stage Predicts Remission
Stage I hilar adenopathy alone, 60 to 90% remit. Stage II adenopathy plus infiltrates, 40 to 70%. Stage III infiltrates alone, 10 to 20%. Stage IV fibrosis, which does not reverse. The staging is radiographic, not sequential: patients do not necessarily pass through the stages in order.
ACE Level Does Not Make the Diagnosis
Sensitivity is only about 60% and specificity is poor. ACE inhibitors lower it, giving a false negative; diabetes and other granulomatous disease raise it. Diagnosis requires compatible imaging plus tissue showing non-caseating granulomas, plus exclusion of the mimics, above all tuberculosis and fungal infection, since the histology looks similar and steroids would be disastrous.
Not Everyone Needs Treatment
Asymptomatic stage I disease is observed, because most of it remits on its own. Treat for organ threat or symptoms: cardiac involvement, neurosarcoidosis, ocular disease, hypercalcemia, progressive lung disease with declining function, or disabling symptoms.
First Line and the Taper
Prednisone 20 to 40 mg daily for 4 to 6 weeks, then a taper over 6 to 12 months, with a higher starting dose for cardiac and neurologic disease. Tapering too quickly is the commonest cause of relapse, and courses shorter than 6 months relapse often enough that they mostly waste the steroid exposure.
Steroid-Sparing When the Course Is Long
Methotrexate 10 to 15 mg weekly is the usual second agent, with folic acid and monitoring of liver tests and blood counts. Azathioprine requires TPMT testing first, because homozygous deficiency causes fatal myelosuppression. Infliximab for refractory disease, after screening for latent tuberculosis, since anti-TNF therapy reactivates it.
Two Complications That Are Missed
Cardiac sarcoidosis causes heart block, ventricular arrhythmia and sudden death, and can be the presenting event. Any conduction abnormality or unexplained cardiomyopathy in a sarcoid patient warrants cardiac MRI or FDG-PET. Hypercalcemia comes from granuloma 1-alpha-hydroxylase converting vitamin D, so it is worsened, not helped, by vitamin D supplementation, and these patients should avoid sun and calcium loading.
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Sarcoidosis
Non-caseating granulomas in multiple organs, lungs involved in ~90%. The hard part is not making the diagnosis, it is deciding who actually needs steroids, because a large proportion of patients resolve on their own.
🧪 Diagnosis and Scadding CXR Staging
Diagnosis requires two things: tissue biopsy showing non-caseating granulomas plus exclusion of other causes (TB, fungal infection, lymphoma, berylliosis). Biopsy accessible tissue: lung (transbronchial), skin, or lymph node.
Stage 0: normal CXR.
Stage I: bilateral hilar lymphadenopathy (BHL) alone. ~60–80% spontaneous remission, which is why observation is a legitimate plan, not neglect.
Stage III: pulmonary infiltrates without lymphadenopathy. ~30% remission.
Stage IV: pulmonary fibrosis. Irreversible, poor prognosis, and the reason you follow PFTs rather than waiting for symptoms.
Lofgren syndrome: BHL + erythema nodosum + polyarthralgia + fever. > 90% spontaneous resolution, so characteristic that biopsy is often not required. More common in young women.
Epidemiology that raises suspicion: peaks at age 25–35, higher incidence and more severe disease in African Americans and Scandinavians.
⚡ Treat vs Observe
Many patients need no treatment at all. Sarcoidosis self-resolves in a large proportion of cases, especially Stage I and Lofgren syndrome. Observation alone is appropriate for the asymptomatic patient with stable disease, and steroids carry real harm over 12+ months.
Progressive pulmonary disease (worsening PFTs, increasing infiltrates): treat, because the endpoint of untreated progression is Stage IV fibrosis, which is irreversible.
Cardiac involvement (heart block, cardiomyopathy, ventricular arrhythmias): treat. Cardiac involvement is a leading cause of death in sarcoidosis.
Neurologic involvement (cranial nerve palsies, CNS mass lesions, seizures): treat.
Hypercalcemia from granulomatous 1,25-dihydroxyvitamin D production: treat.
Renal involvement (nephrocalcinosis, nephrolithiasis from hypercalciuria): treat.
Disfiguring skin disease (lupus pernio): treat.
🚨 Workup and Management, Step by Step
1
Image and stage: CXR for Scadding stage, CT chest to better characterize parenchymal disease and the lymphadenopathy pattern. Stage predicts the odds of spontaneous remission and therefore whether you can watch.
2
Quantify the lung: PFTs, typically restrictive with reduced FVC and DLCO (obstruction is also possible with endobronchial involvement). These are the numbers you will track to decide if disease is progressing.
3
Screen the organs that force treatment: ECG on everyone for heart block (PR prolongation, bundle branch block) and cardiac MRI or PET if abnormal; ophthalmology exam for uveitis even if asymptomatic; serum calcium and 24-hour urine calcium (hypercalciuria can be present with a normal serum calcium); CBC, BMP, LFTs, where an elevated alk phos suggests hepatic granulomas.
4
Biopsy accessible tissue for non-caseating granulomas and rule out the mimics. Defer only in Lofgren syndrome, or in asymptomatic BHL in a young patient with a classic CXR and nothing concerning for lymphoma or infection, though many clinicians still prefer confirmation.
5
Decide: observe or treat. If no treatment indication, observe with serial PFTs and imaging. If there is one, start prednisone 20–40 mg daily × 4–6 weeks, then slow taper over 6–12 months, total duration typically 12+ months, because relapse is common (~30–50%) when steroids are tapered. Start higher for severe cardiac or neurologic involvement. NSAIDs cover mild arthralgia and erythema nodosum.
6
Add a steroid-sparing agent when you cannot taper below prednisone 10 mg/day, when steroid side effects accumulate, or when the patient relapses on taper. Methotrexate is the usual choice.
💊 Key Drugs
Prednisone20–40 mg daily × 4–6 wk then taper over 6–12 months; first-line, higher dose for cardiac or neuro involvement
Methotrexate (Trexall)10–15 mg weekly PO/SQ; most common steroid-sparing agent, add folic acid 1 mg daily, avoid in pregnancy (teratogenic)
Azathioprine (Imuran)50–200 mg daily; alternative to MTX, check TPMT first
Mycophenolate (CellCept)500–1500 mg BID; refractory disease, GI side effects common
Infliximab (Remicade)3–5 mg/kg IV at weeks 0, 2, 6 then q4–8 weeks; anti-TNF for severe disease failing conventional therapy, screen for TB first
Hydroxychloroquine200–400 mg daily; useful for skin sarcoidosis, hypercalcemia, and fatigue, annual eye exams for retinal toxicity
📊 Monitoring
PFTs q3–6 months on treatment. FVC and DLCO are the most useful markers of disease activity and are what tell you whether you are preventing Stage IV fibrosis.
CXR or CT chest q6–12 months, interval set by disease severity.
Serum calcium and 24h urine calcium, especially while tapering steroids, since steroid withdrawal can unmask recurrent granulomatous vitamin D activation.
Ophthalmology annually even if asymptomatic, more often with active uveitis, because sight-threatening disease can be silent.
ECG annually, with a low threshold for cardiac MRI or FDG-PET on any new palpitations, syncope, or dyspnea.
LFTs for both hepatic sarcoidosis and drug toxicity (MTX, azathioprine); CBC q4–8 weeks on MTX and for azathioprine or mycophenolate monitoring.
DEXA if on prolonged steroids (> 3 months of prednisone ≥ 5 mg/day), because the treatment course is measured in years.
⚠️ Pitfalls
Using ACE level to diagnose. Sensitivity only ~60% and poor specificity. ACE inhibitors lower it (false negative), diabetes, hyperthyroidism, and other granulomatous diseases raise it (false positive). Never a sole diagnostic criterion.
Following ACE as a disease-activity marker. Some clinicians trend it, but it is not reliable enough to drive treatment decisions; use PFTs and organ-specific markers.
Treating everyone. Stage I and Lofgren syndrome mostly resolve without immunosuppression, and 12+ months of steroids is not a benign exposure.
Skipping the ECG. Cardiac sarcoidosis is a leading cause of death and AV block is often the first sign; screen all patients.
Skipping the eye exam in someone with no eye complaints, when uveitis is frequently asymptomatic early.
Missing hypercalciuria by checking only serum calcium, when the 24-hour urine can be abnormal with a normal serum level.
Calling it sarcoid without excluding the mimics: TB, fungal infection, lymphoma, and berylliosis all produce granulomas or hilar adenopathy.
🏥 Escalate / Refer When
New AV block, palpitations, syncope, or unexplained cardiomyopathy: cardiac MRI (late gadolinium enhancement) or FDG-PET. Consider temporary pacing and evaluation for permanent pacemaker or ICD; ICD if LVEF ≤ 35% or sustained VT. Prednisone 40–60 mg daily for active cardiac sarcoidosis, plus guideline-directed HF therapy.
Cranial nerve palsy, CNS mass lesion, or seizure: neurosarcoidosis, treat rather than observe, and infliximab has the strongest evidence in refractory disease.
Cannot taper below prednisone 10 mg/day, steroid toxicity, or relapse on taper: add methotrexate (or azathioprine, mycophenolate).
Severe disease failing conventional therapy: infliximab, with evidence strongest for lupus pernio and neurosarcoidosis. Screen for TB first, since anti-TNF reactivates latent TB.
Posterior uveitis or optic neuritis refractory to topical therapy: systemic therapy with ophthalmology comanagement.
🎓 Key Evidence and Mechanism
Vorselaars, Chest 2013: methotrexate versus azathioprine as second-line therapy, the basis for methotrexate being the usual first steroid-sparing choice.
Baughman, AJRCCM 2006: infliximab in chronic sarcoidosis with pulmonary involvement, supporting anti-TNF for refractory disease.
Why hypercalcemia happens: activated macrophages in sarcoid granulomas express 1-alpha-hydroxylase, converting 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D. This extra-renal production is not regulated by PTH, so intestinal calcium absorption rises and PTH is appropriately suppressed, unlike primary hyperparathyroidism. Corticosteroids work by suppressing macrophage activity.
Chronic liver inflammation from immune-mediated destruction. Predominantly young women. Type 1 (ANA/ASMA+) is most common. AST/ALT can exceed 1000 in acute flares. High relapse rate if treatment stopped. Elevated IgG is the hallmark serologic finding.
🔍 Overview
Overview
Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease caused by loss of immune tolerance to hepatocytes. It predominantly affects young women (female:male ratio 4:1) but can occur at any age. Can present as acute hepatitis (AST/ALT often >1000) or chronic liver disease with insidious progression to cirrhosis. Associated with other autoimmune conditions (thyroiditis, UC, RA, celiac).
Types
Type 1 (80%) -ANA and/or anti-smooth muscle antibody (ASMA) positive. Adults predominantly. Most common worldwide.
Type 2 -Anti-liver-kidney microsomal antibody (anti-LKM1) positive. More common in children. Tends to be more severe.
🚨 Management
Induction
Standard induction:Prednisone 40-60 mg daily, tapering over 4-8 weeks to 5-10 mg daily, PLUS Azathioprine (Imuran) 50 mg daily at week 2, uptitrated to 1-2 mg/kg.
Alternative:Budesonide (Entocort) 9 mg daily -first-pass hepatic metabolism means fewer systemic side effects. BUT: do NOT use in cirrhotic patients (portosystemic shunts bypass first-pass metabolism, negating the benefit). Manns, Gastroenterology 2010
Maintenance
Azathioprine monotherapy (1-2 mg/kg daily) once steroids are tapered. Aim to maintain on the lowest effective azathioprine dose. Relapse rate is 80-90% if treatment is stopped -most patients need lifelong therapy.
TPMT Testing
Check TPMT before starting azathioprine -homozygous TPMT deficiency causes fatal myelosuppression. Heterozygous patients need dose reduction. Also monitor CBC regularly on azathioprine (q2 weeks for first 2 months, then q3 months).
🧪 Workup
Diagnostic Workup
AST/ALT -often markedly elevated (>1000 in acute flares). Hepatocellular pattern.
IgG levels -elevated IgG is the hallmark. Polyclonal hypergammaglobulinemia.
ANA -positive in Type 1 (not specific for AIH)
ASMA (anti-smooth muscle antibody) -more specific for Type 1 AIH
Anti-LKM1 -diagnostic of Type 2 AIH
Liver biopsy -interface hepatitis (lymphoplasmacytic infiltrate at the portal-parenchymal junction) is classic. May show bridging necrosis in severe cases.
Rule out other causes:
Viral hepatitis -Hep A IgM, HBsAg, anti-HBc, anti-HCV, Hep E IgM
Drug-induced liver injury -thorough medication history
Wilson disease -ceruloplasmin (especially in patients <40)
Simplified AIH Scoring System -uses ANA/SMA titers, IgG levels, liver histology, and exclusion of viral hepatitis. Score >=7 = definite AIH.
💊 Medications
Medications
Drug
Dose
Route
Notes
Prednisone INDUCTION
40-60 mg daily, taper to 5-10 mg over 4-8 weeks
PO
Standard induction. Monitor glucose, BP, bone density on prolonged use.
Azathioprine (Imuran) MAINTENANCE
50 mg daily initially, uptitrate to 1-2 mg/kg
PO
Check TPMT BEFORE starting. Fatal myelosuppression if homozygous deficient. Monitor CBC q2 weeks x 2 months, then q3 months. AASLD 2020
Budesonide (Entocort)
9 mg daily (3 mg TID)
PO
Alternative to prednisone. First-pass metabolism = fewer systemic effects. Do NOT use in cirrhosis.
Mycophenolate (CellCept)
1-2 g daily
PO
Second-line for azathioprine-intolerant patients. Teratogenic -avoid in pregnancy.
Tacrolimus (Prograf)
1-6 mg daily (target trough 3-5 ng/mL)
PO
Salvage therapy for refractory AIH. Monitor trough levels and renal function.
🏥 Rounds
Pimp Questions
❓ Why can't you use budesonide in cirrhotic patients with AIH?
Budesonide has high first-pass hepatic metabolism -normally 90% is cleared by the liver, so systemic exposure is minimal. In cirrhosis, portosystemic shunts bypass the liver, so budesonide enters systemic circulation at high levels -losing its advantage over prednisone and causing full systemic steroid side effects. Use prednisone instead.
❓ What is the most important lab to distinguish AIH from other causes of hepatitis?
IgG level. Elevated IgG (polyclonal hypergammaglobulinemia) is the hallmark of AIH and is part of the simplified diagnostic criteria. While ANA and ASMA are useful, they are not specific -ANA can be positive in many conditions. IgG elevation combined with autoantibodies and interface hepatitis on biopsy is the diagnostic triad.
❓ Why must you check TPMT before starting azathioprine?
Azathioprine is metabolized by thiopurine methyltransferase (TPMT). Patients with homozygous TPMT deficiency (~0.3% of population) accumulate toxic metabolites causing fatal myelosuppression -severe pancytopenia. Heterozygous patients (~10%) need dose reduction. Testing prevents a completely preventable catastrophic drug reaction.
❓ What happens when you try to stop AIH treatment?
The relapse rate is 80-90% when treatment is withdrawn, even after achieving biochemical remission. Most patients require lifelong immunosuppression with low-dose azathioprine. Consider attempting withdrawal only after: (1) sustained biochemical remission for >2 years, (2) confirmed histologic remission on repeat biopsy, and (3) very close follow-up with labs q2-4 weeks after stopping.
Clinical Examples
📋 Case 1, Classic Type 1 AIH Presentation
Patient: 32F with 3 weeks of fatigue, jaundice, RUQ pain. AST 1180, ALT 1420, T. bili 7.6, INR 1.2. IgG 3400 (markedly elevated). ANA 1:320, ASMA 1:160. Viral hepatitis negative. Biopsy: interface hepatitis with plasma cells.
Key findings: Type 1 AIH (ANA/ASMA positive). Simplified AIH score ≥ 7 = definite. Interface hepatitis with lymphoplasmacytic infiltrate is the hallmark histologic finding.
Management:
Prednisone 40-60 mg daily (or budesonide 9 mg daily if non-cirrhotic), expect ALT improvement within 2 weeks
Add azathioprine 50 mg daily after 2 weeks → titrate to 1-2 mg/kg (check TPMT first!)
Goal: biochemical remission (normal ALT + IgG) within 6-12 months
Taper prednisone slowly over 3-6 months → maintain on azathioprine monotherapy
Relapse rate 80-90% if treatment stopped, most patients need lifelong azathioprine
Teaching point: AIH responds dramatically to steroids, if ALT does not improve within 2 weeks, reconsider the diagnosis. The combination of prednisone + azathioprine allows faster steroid taper and fewer steroid side effects.
📋 Case 2, Acute Severe AIH (Fulminant Presentation)
Patient: 24F with 1 week of rapidly worsening jaundice, confusion. AST 2800, ALT 3200, T. bili 18, INR 3.8, albumin 2.4. IgG 4200. ANA 1:640. Developing hepatic encephalopathy grade II.
Key findings: Acute severe AIH with impending liver failure (INR > 1.5 + encephalopathy = acute liver failure criteria). Must decide quickly: steroids or transplant listing.
Management:
Methylprednisolone 60 mg IV daily, trial of steroids for 7 days maximum
If improving (bilirubin decreasing, INR improving by day 7): continue steroids, add azathioprine
If NOT improving or worsening: list for emergent liver transplant (MELD exception)
LILLE score or similar at day 7 to objectively assess steroid response
ICU monitoring, lactulose for encephalopathy, FFP only if actively bleeding (don't mask INR trend)
Teaching point: Acute severe AIH gets a 7-day steroid trial, this is both diagnostic and therapeutic. If no response, proceeding with steroids delays transplant listing. The key is having a clear timeline and objective response criteria before starting.
📋 Case 3, AIH Flare on Azathioprine (Non-Compliance)
Patient: 40F with known AIH in remission on azathioprine 150 mg daily. Stopped taking it 3 months ago (felt well). Now AST 680, ALT 820, IgG 2800, bilirubin 4.2. Previously well-controlled.
Key findings: AIH flare from medication non-compliance. This is the most common reason for relapse. Predictable, 80-90% relapse when therapy is withdrawn.
Restart azathioprine at previous effective dose (150 mg daily)
Taper prednisone once ALT normalizing → maintain azathioprine indefinitely
Counsel: AIH requires lifelong therapy in most patients. Stopping medication risks flare → fibrosis progression
Repeat liver biopsy if concern for interval fibrosis progression from uncontrolled inflammation
Teaching point: Each untreated flare accelerates fibrosis. Patients who relapse after stopping therapy should generally never attempt withdrawal again, the risk-benefit clearly favors lifelong low-dose azathioprine over recurrent flares and progressive liver damage.
Sample Presentation
Ms. Patel is a 28-year-old woman with no significant past medical history presenting with 2 weeks of fatigue, jaundice, and RUQ discomfort. Labs: AST 1,240, ALT 1,580, total bilirubin 8.4, INR 1.3, albumin 3.2. IgG markedly elevated at 3,200 (normal <1600). ANA 1:320, ASMA 1:160. Hepatitis A, B, C, E serologies negative. Ceruloplasmin normal. Liver biopsy: interface hepatitis with lymphoplasmacytic infiltrate. Simplified AIH score: 8 (definite AIH).
Key Points: Classic Type 1 AIH in a young woman -markedly elevated transaminases, elevated IgG, positive ANA/ASMA, interface hepatitis on biopsy. Check TPMT, start prednisone 60 mg daily, add azathioprine 50 mg at week 2. Monitor for steroid side effects. Counsel that lifelong therapy is likely needed (80-90% relapse rate if stopped).
Monitoring
LFTs (AST/ALT) -q2-4 weeks during induction, then q3 months on maintenance. Goal: normalization of transaminases.
IgG level -normalize with successful treatment. Useful marker of disease activity.
CBC -monitor for azathioprine myelosuppression. q2 weeks for first 2 months, then q3 months.
TPMT result -must have before starting azathioprine.
Liver biopsy -consider repeat biopsy before treatment withdrawal to confirm histologic remission (biochemical remission does NOT guarantee histologic remission).
Predominantly young women, though it occurs at any age and in men. Presentation ranges from an incidental transaminase rise to acute hepatitis, and AST and ALT can exceed 1,000 in a flare, which puts it on the same differential as viral and drug-induced hepatitis. Roughly a third already have cirrhosis at diagnosis, because the earlier disease was silent.
The Serologic Hallmark Is a Raised IgG
An elevated IgG with autoantibodies is the classic pattern.Type 1: ANA and anti-smooth muscle antibody, the commonest form, all ages.Type 2: anti-LKM-1, mostly children and young adults, and typically more aggressive.Seronegative autoimmune hepatitis exists, so negative antibodies with a compatible picture do not exclude it.
Biopsy Before Committing to Treatment
Interface hepatitis with a plasma cell infiltrate is the characteristic finding, and the biopsy also stages fibrosis, which changes the prognosis and the monitoring. Exclude the mimics first: viral hepatitis, drug-induced liver injury, Wilson disease in anyone under 40, alpha-1 antitrypsin deficiency, and the overlap syndromes with PBC and PSC.
Induce With Steroids
Prednisone 40 to 60 mg daily, or a lower steroid dose combined with azathioprine from the start, which reduces the cumulative steroid exposure. Budesonide is an option in non-cirrhotic disease because of high first-pass metabolism, but not in cirrhosis, where portosystemic shunting removes that advantage and raises systemic exposure and portal vein thrombosis risk.
Check TPMT Before Azathioprine
Homozygous TPMT deficiency causes fatal myelosuppression, and heterozygotes need a dose reduction. Monitor the CBC every 2 weeks for the first 2 months, then every 3 months. This is a single test that prevents a preventable death, and it must be sent before the first dose, not after.
Do Not Stop Treatment Early
The relapse rate is high, and most relapses follow premature withdrawal.Continue maintenance for at least 2 to 3 years, and only consider withdrawal after biochemical remission with a normal IgG plus histologic remission on repeat biopsy. Many patients need lifelong therapy, and repeated relapse-and-retreat cycles cause more cumulative damage than staying on maintenance.
Track Response by ALT and IgG
Biochemical remission is a normal ALT with a normal IgG, and normalizing the transaminase alone is not enough, since ongoing histologic activity persists with a normal ALT. Check labs every 1 to 2 weeks initially, then every 3 to 6 months.Second-line agents for non-responders: mycophenolate, tacrolimus or cyclosporine.
Manage the Long-Term Consequences
Bone protection with calcium, vitamin D and a bone density scan, because these patients are on steroids for years. Screen for hepatocellular carcinoma every 6 months once cirrhotic.Vaccinate against hepatitis A and B before immunosuppression.Acute severe presentation with encephalopathy needs transplant center referral, since steroid failure there is rapid and the window for listing is short.
RoundsRx Infographic Series · #170 · Gastro & Hepatology · PDF 138 KB
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GI · One Pager
Autoimmune Hepatitis
Elevated IgG plus autoantibodies plus interface hepatitis in a young woman: steroids induce, azathioprine maintains, and stopping therapy relapses 80 to 90% of the time.
🧪 Diagnosis
Elevated IgG is the hallmark (polyclonal hypergammaglobulinemia), and it is what separates AIH from other hepatitides
AST/ALT hepatocellular pattern, often >1000 in acute flares
ANA and/or ASMA positive in Type 1 (80%, adults). ANA is not specific for AIH; ASMA is more specific
Anti-LKM1 is diagnostic of Type 2 (more common in children, tends to be more severe)
Liver biopsy shows interface hepatitis (lymphoplasmacytic infiltrate at the portal-parenchymal junction), bridging necrosis if severe
Simplified AIH Score ≥7 = definite AIH, built from ANA/SMA titers, IgG, histology, and exclusion of viral hepatitis
⚡ Rule Out Before You Commit
Viral hepatitis: Hep A IgM, HBsAg, anti-HBc, anti-HCV, Hep E IgM, because immunosuppressing active viral hepatitis is harmful
Drug-induced liver injury: thorough medication history, DILI can mimic the biochemistry exactly
Wilson disease: ceruloplasmin, especially in patients <40 where it is most likely to be missed
Who gets it: predominantly young women (female:male 4:1), any age. Look for associated autoimmunity (thyroiditis, UC, RA, celiac)
🚨 Induction to Maintenance, Step by Step
1
Check TPMT first: homozygous deficiency plus azathioprine causes fatal myelosuppression. Heterozygotes need dose reduction. This is a completely preventable catastrophe
2
Induce with prednisone 40 to 60 mg daily: AIH responds dramatically to steroids. If ALT does not improve within 2 weeks, reconsider the diagnosis
3
Add azathioprine 50 mg daily at week 2, uptitrate to 1 to 2 mg/kg. The combination allows a faster steroid taper and fewer steroid side effects
4
Taper prednisone to 5 to 10 mg over 4 to 8 weeks, then off, leaving azathioprine monotherapy at the lowest effective dose
5
Target biochemical remission (normal ALT + normal IgG) within 6 to 12 months, then continue indefinitely: relapse is 80 to 90% if therapy is stopped, so most patients need lifelong treatment
💊 Key Drugs
Prednisone (induction)40 to 60 mg PO daily, taper to 5 to 10 mg over 4 to 8 weeks
Azathioprine (Imuran, maintenance)50 mg PO daily, uptitrate to 1 to 2 mg/kg. TPMT first
Budesonide (Entocort)9 mg PO daily (3 mg TID). Not in cirrhosis
Mycophenolate (CellCept)1 to 2 g PO daily if azathioprine-intolerant. Teratogenic
Tacrolimus (Prograf)1 to 6 mg PO daily, target trough 3 to 5 ng/mL, salvage only
📊 Monitoring
AST/ALT q2 to 4 weeks during induction, then q3 months on maintenance, because normalization of transaminases is the treatment goal
IgG level alongside LFTs, it normalizes with successful treatment and is a useful marker of ongoing disease activity
CBC q2 weeks for the first 2 months, then q3 months, to catch azathioprine myelosuppression before it becomes pancytopenia
Repeat liver biopsy before any withdrawal attempt, because biochemical remission does NOT guarantee histologic remission
HCC screening (ultrasound + AFP q6 months) if cirrhotic, standard cirrhosis surveillance applies
DEXA if steroids are prolonged, to catch steroid bone loss. Also watch glucose and BP on prednisone
⚠️ Pitfalls
Starting azathioprine without TPMT. Homozygous deficiency (~0.3%) means toxic metabolite accumulation and fatal pancytopenia
Budesonide in a cirrhotic. Its whole advantage is ~90% first-pass hepatic clearance; portosystemic shunts bypass the liver, so you get full systemic steroid exposure with no benefit. Use prednisone
Stopping therapy because the patient feels well. Non-compliance is the most common reason for relapse, and each untreated flare accelerates fibrosis
Calling it AIH without excluding viral hepatitis, DILI, and Wilson. The autoantibodies are not specific enough to stand alone
Continuing steroids past day 7 in acute severe AIH that is not responding, which just delays transplant listing
🏥 Escalate / Refer When
INR >1.5 plus encephalopathy = acute liver failure. Methylprednisolone 60 mg IV daily as a 7-day maximum steroid trial, both diagnostic and therapeutic
No improvement in bilirubin or INR by day 7: list for emergent transplant (MELD exception). Assess objectively (LILLE score or similar) rather than by gestalt
ALT not improving within 2 weeks of steroids: reconsider the diagnosis, this disease normally responds fast
Azathioprine intolerance or refractory disease: mycophenolate second-line, tacrolimus as salvage, both hepatology-directed
Withdrawal attempt only if sustained biochemical remission >2 years, confirmed histologic remission on repeat biopsy, and labs q2 to 4 weeks after stopping
🎓 Key Evidence
Manns, Gastroenterology 2010: budesonide 9 mg daily is a valid prednisone alternative for induction in non-cirrhotic AIH, with fewer systemic steroid effects
AASLD 2020: underpins the azathioprine maintenance strategy, TPMT testing before starting, and CBC monitoring q2 weeks × 2 months then q3 months
Diagnostic triad to carry: elevated IgG + autoantibodies (ANA, ASMA, anti-LKM1) + interface hepatitis on biopsy
Two distinct cholestatic liver diseases. PBC: anti-mitochondrial antibody positive, middle-aged women, responds to ursodiol. PSC: associated with UC, beading on MRCP, young men, NO proven medical therapy. Both can progress to cirrhosis.
🔍 Overview
PBC vs PSC Comparison
Feature
PBC (Primary Biliary Cholangitis)
PSC (Primary Sclerosing Cholangitis)
Gender
90% female
~70% male
Age
Middle-aged (40-60)
Young adults (30-40)
Key Antibody
Anti-mitochondrial antibody (AMA) -95% sensitive
p-ANCA (nonspecific)
Imaging
Normal bile ducts on MRCP
Beading on MRCP (multifocal strictures + dilations)
Pathology
Destruction of small intrahepatic bile ducts
Inflammation and fibrosis of intra- and extrahepatic bile ducts
Incomplete response to UDCA: add a PPAR agonist: elafibranor (Iqirvo) 80 mg daily (dual PPAR-alpha/delta) or seladelpar (Livdelzi) 10 mg daily (PPAR-delta), each given with UDCA, or alone if UDCA is not tolerated. Add if ALP >1.67x ULN or bilirubin elevated after 12 months of UDCA. Bezafibrate or fenofibrate are off-label alternatives. CHANGED 2025Obeticholic acid (Ocaliva) is no longer available in the US: it was withdrawn at FDA request over a risk of serious liver injury, including in patients without cirrhosis, and the approval was formally withdrawn in November 2025. Do not prescribe it. POISE, NEJM 2016
Pruritus management: Cholestyramine (first-line for itch), rifampin, naltrexone, sertraline
Liver transplant for decompensated cirrhosis. PBC can recur post-transplant but rarely clinically significant.
PSC Management
NO proven medical therapy -this is the critical teaching point.
Ursodiol is commonly prescribed but does NOT improve transplant-free survival in PSC. High-dose ursodiol (28-30 mg/kg) was actually HARMFUL -increased mortality, need for transplant, and serious adverse events. Lindor, Hepatology 2009
ERCP with balloon dilation for dominant strictures causing cholangitis or progressive jaundice.
Liver transplant -definitive treatment. PSC can recur post-transplant (~20%).
Cancer screening: CA 19-9 + MRCP annually for cholangiocarcinoma. Colonoscopy annually if concomitant UC (elevated colon cancer risk).
Updated Practice: Ursodiol works for PBC but NOT for PSC. Despite widespread use, ursodiol has not been shown to improve transplant-free survival in PSC. High-dose ursodiol (28-30 mg/kg) was actually HARMFUL in PSC (Lindor, Hepatology 2009). Standard-dose ursodiol may improve LFTs but without clinical outcomes benefit.
🧪 Workup
PBC Workup
AMA (anti-mitochondrial antibody) -95% sensitive and highly specific for PBC. AMA-positive + cholestatic LFTs often sufficient for diagnosis without biopsy.
LFTs -cholestatic pattern: elevated ALP, GGT. ALT/AST may be mildly elevated.
IgM -typically elevated in PBC (vs. IgG in AIH)
Liver biopsy -may not be needed if AMA+ with typical cholestatic LFTs. Shows granulomatous destruction of small bile ducts ("florid duct lesion").
PSC Workup
MRCP -diagnostic study of choice. Shows multifocal strictures and dilations of intra- and/or extrahepatic bile ducts ("beading" or "string of pearls").
LFTs -cholestatic pattern (elevated ALP, GGT).
p-ANCA -positive in ~80% but not specific.
Colonoscopy -screen for UC even if asymptomatic (70% of PSC patients have UC).
CA 19-9 -baseline and annually for cholangiocarcinoma screening.
Liver biopsy -"onion skin" periductal fibrosis is classic but often not needed if MRCP is diagnostic.
💊 Medications
Medications
Drug
Indication
Dose
Notes
Ursodiol (UDCA) PBC 1ST LINE
PBC
13-15 mg/kg/day PO
Improves LFTs and transplant-free survival in PBC. Split BID. Take with food. NOT effective for PSC.
Elafibranor (Iqirvo) / Seladelpar (Livdelzi)
PBC (UDCA-incomplete)
Elafibranor 80 mg daily; seladelpar 10 mg daily
PPAR agonists, given with UDCA or alone if UDCA is not tolerated. These replaced obeticholic acid, which was withdrawn from the US market in 2025 for hepatotoxicity. Seladelpar may also improve pruritus, which the older agent worsened. POISE, NEJM 2016
Cholestyramine
Pruritus (PBC/PSC)
4 g BID-QID
First-line for cholestatic pruritus. Separate from other medications by 2-4 hours (bile acid sequestrant binds drugs).
Rifampin
Pruritus (refractory)
150-300 mg BID
Second-line for pruritus. Monitor LFTs (hepatotoxic). Effective in PBC/PSC-related itch.
Naltrexone
Pruritus (refractory)
25-50 mg daily
Opioid antagonist for cholestatic pruritus. Can precipitate opioid withdrawal -start low dose.
🏥 Rounds
Pimp Questions
❓ Why does ursodiol work for PBC but not PSC?
In PBC, toxic bile acids cause destruction of small bile ducts. Ursodiol replaces toxic bile acids with a hydrophilic, non-toxic bile acid, reducing cholangiocyte injury. In PSC, the pathology is fibrosis and stricturing of large bile ducts -a different mechanism not addressed by changing bile acid composition. The high-dose UDCA trial in PSC actually showed HARM -possibly because retained ursodiol above strictures caused hepatotoxicity.
❓ What cancer are you most worried about in PSC?
Cholangiocarcinoma -lifetime risk 10-15%. Can be very difficult to detect because it arises in the setting of already-abnormal bile ducts. Screen with CA 19-9 + MRCP annually. Any new dominant stricture should raise suspicion -brush cytology via ERCP with FISH analysis. Also at risk for gallbladder cancer and colon cancer (if UC).
❓ How do you distinguish PBC from PSC on labs and imaging?
Both are cholestatic (elevated ALP, GGT). PBC: AMA positive (95%), normal bile ducts on MRCP, typically middle-aged woman. PSC: AMA negative, beading/strictures on MRCP, typically young man with UC. The bile ducts on MRCP are the key differentiator -if MRCP is normal but cholestasis persists, think PBC (small duct disease not visible on imaging).
Clinical Examples
📋 Case 1, Primary Biliary Cholangitis (PBC)
Patient: 52F with fatigue and pruritus × 1 year. ALP 380, GGT 290, ALT 62, bilirubin 1.8. AMA positive (titer 1:640). MRCP: normal bile ducts. Liver biopsy: florid duct lesion with granulomatous destruction of small bile ducts.
Key findings: Classic PBC: middle-aged woman + cholestatic labs + AMA positive + normal MRCP. Biopsy confirms but is not required if AMA > 1:40 + cholestatic pattern.
Assess response at 1 year: ALP < 1.67× ULN = adequate response (Paris criteria)
If inadequate response: add a PPAR agonist, elafibranor 80 mg daily or seladelpar 10 mg daily. Obeticholic acid was withdrawn from the US market in 2025 for hepatotoxicity and should no longer be used
Cholestyramine 4g BID-QID for pruritus (bile acid sequestrant). If refractory: rifampin, naltrexone
Screen for osteoporosis (cholestasis impairs vitamin D absorption), hypothyroidism (autoimmune overlap)
Teaching point: PBC is diagnosed by AMA + cholestatic labs, biopsy is rarely needed. Ursodiol slows progression to cirrhosis and improves transplant-free survival. Response at 1 year predicts long-term outcome.
📋 Case 2, PSC with Dominant Stricture
Patient: 34M with UC on mesalamine. Progressive jaundice, pruritus, RUQ pain. ALP 520, bilirubin 6.8, CA 19-9 42 (mildly elevated). MRCP: multifocal beading/strictures with dominant stricture at common hepatic duct.
Key findings: PSC with dominant stricture, must rule out cholangiocarcinoma (CCA). Lifetime CCA risk in PSC is 10-15%. Any new dominant stricture or rapidly rising bilirubin/CA 19-9 is concerning.
Management:
ERCP with brush cytology + FISH analysis of dominant stricture (rule out CCA)
If benign: balloon dilation of dominant stricture ± short-term stent placement
No role for ursodiol in PSC (high-dose UDCA showed harm in trials)
Annual CCA screening: CA 19-9 + MRCP
Colonoscopy annually (PSC + UC = very high colon cancer risk, right-sided predominance)
Teaching point: PSC has no effective medical therapy, treatment is managing complications and screening for malignancy. Liver transplant is the only curative option, but PSC recurs in 20-25% of transplanted livers.
📋 Case 3, PBC-AIH Overlap Syndrome
Patient: 45F with fatigue, ALP 320, ALT 280 (mixed pattern). AMA positive (1:320), ANA positive (1:160), IgG 2800 mg/dL (elevated). Biopsy: interface hepatitis with plasma cells AND bile duct destruction.
Key findings: PBC-AIH overlap syndrome (~10% of PBC patients). Features of both: cholestatic pattern (ALP elevated, AMA+) + hepatitic pattern (high ALT, high IgG, interface hepatitis on biopsy).
Management:
Ursodiol 13-15 mg/kg/day (for the PBC component)
Add prednisone 30 mg daily → taper + azathioprine 50 mg → titrate to 1-2 mg/kg (for the AIH component)
Monitor ALT and ALP separately, both should improve with dual therapy
Check TPMT before starting azathioprine (risk of myelosuppression if deficient)
Long-term: aim for biochemical remission (normal ALT + ALP < 1.5× ULN)
Teaching point: Overlap syndrome is suspected when a PBC patient has disproportionately elevated transaminases (ALT > 5× ULN) or elevated IgG. Biopsy is essential, interface hepatitis confirms the AIH component and justifies adding immunosuppression.
Sample Presentation
Mr. Olsen is a 32-year-old man with ulcerative colitis on mesalamine, presenting with progressive jaundice, pruritus, and fatigue over 3 months. Labs: ALP 480, GGT 320, ALT 85, bilirubin 4.2. p-ANCA positive. MRCP shows multifocal intrahepatic and extrahepatic bile duct strictures with beading pattern. Dominant stricture at the common hepatic duct with upstream dilation.
Key Points: Classic PSC -young man with UC, cholestatic LFTs, beading on MRCP. NO medical therapy improves outcomes. Dominant stricture causing jaundice -refer for ERCP with balloon dilation. Start cholangiocarcinoma screening (CA 19-9 + MRCP annually). Ensure annual colonoscopy for UC-associated colon cancer. Discuss liver transplant referral given progressive disease.
PBC Monitoring
LFTs -q3-6 months. Track ALP response to UDCA. Incomplete response: ALP >1.67x ULN after 12 months.
Bilirubin -rising bilirubin is the strongest predictor of poor prognosis in PBC.
Thyroid function -screen for hypothyroidism (frequently associated).
DEXA -osteoporosis risk is elevated in cholestatic liver disease.
Fat-soluble vitamins -A, D, E, K. Malabsorption from cholestasis.
PSC Monitoring
CA 19-9 + MRCP -annually for cholangiocarcinoma screening.
Colonoscopy -annually if concomitant UC (elevated colon cancer risk). Even after liver transplant.
LFTs -q3-6 months. New cholangitis episodes may indicate dominant stricture.
Gallbladder ultrasound -annually. Increased gallbladder cancer risk. Low threshold for cholecystectomy if polyps found.
📋 Summary
Summary
Two Diseases, One Presentation
Both give cholestatic liver tests with a raised alkaline phosphatase, pruritus and fatigue long before jaundice. The demographics separate them at the door: PBC is 90% female, aged 40 to 60; PSC is about 70% male, aged 30 to 40.
PBC: Antibody Makes the Diagnosis
Anti-mitochondrial antibody is 95% sensitive, and a positive AMA with a cholestatic pattern is enough. Bile ducts look normal on MRCP because the target is the small intrahepatic ducts. Biopsy is not needed unless the AMA is negative or an overlap with autoimmune hepatitis is suspected.
PSC: Imaging Makes the Diagnosis
Multifocal strictures with intervening dilation, the beaded appearance on MRCP.p-ANCA is nonspecific and does not make the diagnosis. The disease involves intra- and extrahepatic ducts, which is why it causes recurrent cholangitis and dominant strictures that PBC does not.
Ursodiol Works in PBC and Not in PSC
PBC: ursodiol 13 to 15 mg/kg/day improves survival and delays transplant, and it is the reason PBC is now a treatable disease.PSC: ursodiol has never shown a transplant-free survival benefit, and high-dose 28 to 30 mg/kg was actively harmful. Despite that, it is still widely prescribed.
Second Line in PBC
Assess the response at 12 months on alkaline phosphatase and bilirubin.Inadequate responders get a PPAR agonist, elafibranor or seladelpar, or a fibrate, and roughly 40% of patients are inadequate responders, which is why the 12-month check matters. Obeticholic acid was withdrawn from the US market in 2025 for a risk of serious liver injury, so the second-line landscape changed entirely.
PSC Has No Medical Therapy
Management is surveillance and mechanical.ERCP with dilation, and stenting where needed, for a dominant stricture presenting as sudden jaundice or cholangitis, and antibiotics for cholangitis episodes. Transplant is the only intervention that changes the natural history.
The Cancer Risk Is the Reason for Surveillance
PSC carries a lifetime cholangiocarcinoma risk of roughly 10 to 15% → annual MRCP with CA 19-9. PSC is associated with ulcerative colitis in most patients, and the combination raises colorectal cancer risk enough to warrant annual colonoscopy rather than the usual interval. Gallbladder polyps in PSC are treated as malignant until proven otherwise. PBC carries a hepatocellular carcinoma risk once cirrhotic → imaging every 6 months.
Treat the Symptoms and the Consequences
Pruritus is often the worst part of the illness: cholestyramine first, then rifampin, naltrexone or sertraline. Fat-soluble vitamin deficiency (A, D, E, K) follows from fat malabsorption, so check and replace. Screen bone density, because osteoporosis is common in chronic cholestasis and is easy to forget in an otherwise young patient.
RoundsRx Infographic Series · #168 · Gastro & Hepatology · PDF 142 KB
Text version
GI · One Pager
PBC vs PSC
Two different cholestatic diseases that must never be blurred: PBC is AMA-positive small-duct disease in middle-aged women where ursodiol works, PSC is large-duct beading in young men with UC where no medical therapy works.
🧪 PBC (Primary Biliary Cholangitis)
Who: 90% female, middle-aged (40 to 60). Presents with pruritus and fatigue
Antibody:AMA (anti-mitochondrial antibody), 95% sensitive and highly specific. AMA-positive plus cholestatic LFTs is often enough to diagnose without biopsy
Imaging:normal bile ducts on MRCP, because the target is small intrahepatic ducts that imaging cannot see
Pathology: granulomatous destruction of small intrahepatic bile ducts, the "florid duct lesion"
Associations: Sjogren, thyroiditis, celiac, RA
Cancer risk: hepatocellular carcinoma, only once cirrhotic
🧪 PSC (Primary Sclerosing Cholangitis)
Who: ~70% male, young adults (30 to 40). Pruritus, jaundice, RUQ pain, recurrent cholangitis episodes
Antibody:p-ANCA positive in ~80% but nonspecific, so it does not make the diagnosis. AMA is negative
Labs: cholestatic pattern (ALP, GGT up). CA 19-9 at baseline for later cancer surveillance
Imaging:MRCP is the diagnostic study of choice, showing multifocal strictures and dilations of intra- and/or extrahepatic ducts ("beading", "string of pearls")
Pathology: "onion skin" periductal fibrosis, often not needed if MRCP is diagnostic
Associations:ulcerative colitis in 70%, so colonoscopy even if asymptomatic
Cancer risk:cholangiocarcinoma, lifetime 10 to 15%, plus gallbladder cancer and colon cancer if UC
🚨 Treatment, Paired So You Do Not Cross Them
1
PBC, ursodiol (UDCA) 13 to 15 mg/kg/day split BID: improves LFTs, delays histologic progression, and improves transplant-free survival. This is first-line and it genuinely works
2
PBC, reassess at 12 months: if ALP >1.67× ULN or bilirubin is elevated, that is an incomplete response, so add a PPAR agonist, elafibranor 80 mg daily or seladelpar 10 mg daily, alongside UDCA. Obeticholic acid is no longer available in the US, having been withdrawn in 2025 for hepatotoxicity
3
PSC, NO proven medical therapy. This is the critical teaching point. Ursodiol does NOT improve transplant-free survival in PSC, and high-dose ursodiol (28 to 30 mg/kg) was actively HARMFUL, increasing mortality, transplant need, and serious adverse events
4
PSC, ERCP with balloon dilation for a dominant stricture causing cholangitis or progressive jaundice, with brush cytology plus FISH first to exclude cholangiocarcinoma
5
Both diseases, pruritus ladder: cholestyramine first-line, then rifampin, naltrexone, sertraline. Liver transplant for decompensated cirrhosis in either. PBC can recur post-transplant but rarely matters clinically; PSC recurs in ~20%
💊 Key Drugs
Ursodiol (UDCA), PBC first-line13 to 15 mg/kg/day PO split BID with food. Not effective for PSC
Elafibranor (Iqirvo) or seladelpar (Livdelzi), PBC incomplete respondersElafibranor 80 mg daily, seladelpar 10 mg daily, with UDCA. These replaced obeticholic acid, withdrawn from the US market in 2025
Cholestyramine, pruritus first-line4 g BID to QID, separate from other drugs by 2 to 4 hours since it binds them
Rifampin, pruritus second-line150 to 300 mg BID, monitor LFTs (hepatotoxic)
Naltrexone, refractory pruritus25 to 50 mg daily, start low to avoid precipitating opioid withdrawal
📊 Monitoring
PBC, LFTs q3 to 6 months: track the ALP response to UDCA, since ALP >1.67× ULN at 12 months defines incomplete response and triggers add-on therapy
PBC, bilirubin: a rising bilirubin is the strongest predictor of poor prognosis
PBC, thyroid function and DEXA: hypothyroidism is frequently associated, and cholestatic liver disease carries elevated osteoporosis risk
PBC, fat-soluble vitamins A, D, E, K: cholestasis causes malabsorption
PSC, CA 19-9 + MRCP annually for cholangiocarcinoma, which is hard to spot against already-abnormal ducts
PSC, colonoscopy annually if UC, including after liver transplant, because the colon cancer risk persists
PSC, gallbladder ultrasound annually: increased gallbladder cancer risk, low threshold for cholecystectomy if polyps
PSC, LFTs q3 to 6 months: new cholangitis episodes may signal a dominant stricture
⚠️ Pitfalls
Giving ursodiol for PSC and calling it treated. It is widely prescribed but does not improve transplant-free survival, and high-dose was harmful
Assigning AMA to PSC or beading to PBC. AMA positive plus normal MRCP is PBC; AMA negative plus beading is PSC
Treating a new dominant stricture in PSC as benign. Get brush cytology with FISH before dilating, cholangiocarcinoma lives there
Obeticholic acid at all: it was withdrawn from the US market in 2025 for hepatotoxicity. Black box contraindication, and it makes pruritus worse in everyone
Missing PBC-AIH overlap (~10% of PBC). Disproportionate transaminases (ALT >5× ULN) or elevated IgG should prompt biopsy, since interface hepatitis justifies adding immunosuppression
🏥 Escalate / Refer When
PSC with a dominant stricture plus rising bilirubin or CA 19-9: ERCP with brush cytology and FISH to rule out cholangiocarcinoma before anything else
PBC with ALP >1.67× ULN or elevated bilirubin after 12 months of UDCA: hepatology for a PPAR agonist (elafibranor or seladelpar), this defines the inadequate responder
Decompensated cirrhosis in either disease: transplant referral, this is the definitive treatment and the only curative option in PSC
PBC patient with ALT >5× ULN or elevated IgG: biopsy for overlap syndrome, because the AIH component needs prednisone plus azathioprine (check TPMT) on top of ursodiol
New PSC diagnosis: colonoscopy even if asymptomatic, since 70% have UC and it changes surveillance
🎓 Key Evidence
Poupon, NEJM 1991: established ursodiol as PBC first-line therapy
POISE, NEJM 2016: obeticholic acid improved ALP in PBC patients with an inadequate UDCA response
Lindor, Hepatology 2009: high-dose ursodiol (28 to 30 mg/kg) in PSC increased mortality, transplant need, and serious adverse events. This is why "just give ursodiol" is the wrong reflex in PSC
Mechanistic why: ursodiol replaces toxic bile acids with a hydrophilic non-toxic one, which helps PBC's small-duct cholangiocyte injury but does nothing for PSC's large-duct fibrosis and stricturing
Posterior Reversible Encephalopathy Syndrome. Vasogenic edema predominantly in the posterior circulation. Classic presentation: seizures + headache + visual changes + hypertension. MRI is the diagnostic study of choice. Usually reversible if treated promptly.
🔍 Overview
Overview
Posterior Reversible Encephalopathy Syndrome (PRES) is a clinico-radiographic syndrome characterized by vasogenic edema predominantly in the posterior (occipital/parietal) white matter. Pathophysiology: failure of cerebral autoregulation leads to blood-brain barrier breakdown and vasogenic edema.
Common Causes
Severe hypertension -most common trigger. Exceeds upper limit of autoregulation.
Eclampsia / pre-eclampsia -one of the most important causes in young women
Immunosuppressants -tacrolimus, cyclosporine (calcineurin inhibitors) -common in transplant patients
Renal failure -especially with fluid overload and hypertension
Clinical Presentation
Classic features: seizures (most common presenting symptom, 60-75%), headache (50%), visual disturbances (cortical blindness, blurry vision, visual field defects -33%), altered mental status (28%), and hypertension (often severe). Typically acute/subacute onset over hours to days.
🚨 Management
Management Principles
TREAT THE CAUSE -this is the most important step:
Hypertensive emergency: lower BP gradually (IV antihypertensives -nicardipine, labetalol)
Seizure management: Benzodiazepines for acute seizures. Levetiracetam (Keppra) for prophylaxis/maintenance (fewer drug interactions than phenytoin in transplant patients).
BP control: Target 25% reduction in MAP over first few hours. Avoid precipitous drops (risk of ischemia). IV nicardipine or labetalol preferred.
Usually REVERSIBLE if treated promptly -clinical and radiographic improvement typically within days to weeks. Delayed treatment can lead to permanent infarction, hemorrhage, and death.
PRES is a clinical-radiographic diagnosis. MRI is key -CT may miss early changes. Despite the name, PRES is not always posterior (can involve frontal lobes, brainstem, cerebellum) and not always reversible (delayed treatment can cause permanent ischemic injury, hemorrhage, or death).
🧪 Workup
Diagnostic Workup
MRI brain (with FLAIR) -study of choice. Shows bilateral, symmetric white matter edema in posterior regions (occipital/parietal lobes). FLAIR and T2 sequences show hyperintense signal. DWI helps distinguish vasogenic (PRES) from cytotoxic (stroke) edema.
CT head -less sensitive, may appear normal early. Can show low-density areas in posterior regions. Rule out hemorrhage.
BP -often severely elevated (but PRES can occur at normal BPs, especially drug-induced)
BMP -renal function, electrolytes
CBC, LDH, peripheral smear, haptoglobin -rule out TTP/HUS if thrombocytopenia present
Urine protein/Cr ratio -if pregnant or postpartum (pre-eclampsia workup)
Drug levels -tacrolimus, cyclosporine trough levels if applicable
LP -typically not needed. CSF may show mild protein elevation. Mainly to rule out meningitis/encephalitis if diagnosis uncertain.
💊 Medications
Medications
Drug
Indication
Dose
Notes
Nicardipine BP CONTROL
Hypertensive PRES
5 mg/hr IV, titrate by 2.5 mg/hr q5-15 min (max 15 mg/hr)
Preferred -titratable, consistent effect. No cerebral vasoconstriction.
Labetalol
Hypertensive PRES
10-20 mg IV bolus, double q10 min (max 300 mg) or 1-2 mg/min drip
Alternative to nicardipine. Avoid in severe bradycardia, asthma, heart block.
Levetiracetam (Keppra)
Seizure prophylaxis
500-1000 mg IV/PO BID
Preferred in transplant patients (no CYP interactions -does not affect tacrolimus/cyclosporine levels).
Lorazepam (Ativan)
Acute seizures
2-4 mg IV PRN
First-line for acute seizure control.
Magnesium sulfate
Eclampsia-related PRES
4-6 g IV load, then 1-2 g/hr
Standard of care for eclamptic seizures. Also has antihypertensive effect.
🏥 Rounds
Pimp Questions
❓ Why is the posterior circulation preferentially affected in PRES?
The posterior (vertebrobasilar) circulation has less sympathetic innervation than the anterior (carotid) circulation. Sympathetic innervation helps maintain cerebral autoregulation during acute hypertension. Because the posterior circulation lacks this protective mechanism, it is more susceptible to breakthrough hyperperfusion and blood-brain barrier breakdown when BP exceeds the autoregulatory threshold.
❓ How do you differentiate PRES from ischemic stroke on MRI?
Key is DWI (diffusion-weighted imaging). PRES shows vasogenic edema -T2/FLAIR bright, but DWI normal or dark (no restricted diffusion). Ischemic stroke shows cytotoxic edema -DWI bright with corresponding ADC dark (restricted diffusion). If PRES shows restricted diffusion, it suggests progression to infarction (poor prognostic sign).
❓ Why use levetiracetam over phenytoin in transplant patients with PRES?
Phenytoin is metabolized via CYP3A4 and also induces CYP3A4, which metabolizes tacrolimus and cyclosporine. Using phenytoin in transplant patients would dramatically lower immunosuppressant levels, risking acute rejection. Levetiracetam is renally cleared with no CYP interactions, making it the preferred anticonvulsant in this population.
Sample Presentation
Mrs. Kim is a 45-year-old woman who is 6 months post-renal transplant on tacrolimus, presenting with sudden-onset severe headache, blurry vision, and a witnessed generalized tonic-clonic seizure. BP on arrival: 210/115. Neuro exam: confused, bilateral visual field deficits. Tacrolimus trough elevated at 18 (target 5-8). MRI brain: bilateral symmetric T2/FLAIR hyperintensity in the occipital and parietal white matter consistent with vasogenic edema. No restricted diffusion. No hemorrhage.
Key Points: Classic PRES -transplant patient on tacrolimus with HTN emergency + seizure + visual changes + posterior white matter edema on MRI. Management: (1) nicardipine drip for BP control, (2) levetiracetam for seizure management (no CYP interactions with tacrolimus), (3) HOLD tacrolimus (supratherapeutic level likely contributing). Expect clinical improvement within days if treated promptly.
Monitoring
Blood pressure -continuous arterial line or frequent NIBP. Target 25% MAP reduction over first hours, then gradually normalize.
Repeat MRI -in 1-2 weeks to confirm radiographic resolution. If not improving, reconsider diagnosis.
Seizure monitoring -consider continuous EEG if altered mental status persists or recurrent seizures.
Drug levels -if calcineurin inhibitor-related, check trough levels and hold/reduce dose until resolution.
Urine output and renal function -especially if pre-eclampsia or renal failure is the trigger.
📋 Summary
Summary
Recognize the Syndrome
Seizures, headache, visual disturbance and altered mental status, usually with hypertension.Seizure is the commonest presenting feature, and the visual symptoms range from blurring and hemianopia to cortical blindness. Onset is over hours to days rather than the seconds of a stroke.
The Name Is Misleading Twice Over
It is not always posterior: frontal lobes, brainstem, cerebellum and basal ganglia can all be involved. And it is not always reversible: delayed recognition and treatment lead to infarction, hemorrhage and permanent deficit. Treat the fact that the syndrome is potentially reversible as a reason to act fast, not as reassurance.
MRI Is the Test
MRI with FLAIR shows symmetric vasogenic edema in the parieto-occipital white matter.CT may miss early changes entirely, so a normal CT does not exclude it. Diffusion-weighted imaging separates vasogenic edema (no restriction) from infarction (restriction), and that distinction is what stops PRES being treated as a stroke.
Know the Causes You Can Reverse
Severe hypertension and hypertensive emergency; preeclampsia and eclampsia; calcineurin inhibitors (tacrolimus, cyclosporine) and other cytotoxic agents; renal failure; sepsis; autoimmune disease.In a transplant patient, suspect the calcineurin inhibitor even when the level is therapeutic, since PRES is idiosyncratic rather than dose-dependent.
Lower the Blood Pressure, But Not Too Fast
Reduce mean arterial pressure by no more than about 25% in the first hours.Overshooting causes cerebral hypoperfusion and watershed infarction in a brain whose autoregulation is already deranged. Nicardipine 5 mg/h titrated by 2.5 mg/h every 5 to 15 min is preferred: titratable, predictable, and without the cerebral vasoconstriction of some alternatives. Labetalol is the alternative, avoiding it in asthma, bradycardia and heart block.
Remove the Trigger
Stop or reduce the offending drug, and deliver the baby in eclampsia.No amount of blood pressure control fixes PRES while the precipitant is still acting, and in eclampsia delivery is the definitive treatment.
Treat Seizures, Do Not Anticoagulate the Brain
Lorazepam 2 to 4 mg IV for an acute seizure, then levetiracetam 500 to 1,000 mg BID.Levetiracetam is preferred in transplant patients because it has no CYP interactions and does not alter calcineurin inhibitor levels the way phenytoin does. Antiepileptics can usually be stopped after a few weeks to months once imaging resolves, since this is a provoked seizure, not epilepsy.
Expect Recovery, but Follow the Imaging
Most patients improve clinically within days and radiographically within weeks.Repeat MRI to confirm resolution, because persistent change suggests infarction or hemorrhage and predicts residual deficit. Recurrence happens if the trigger returns, so document the cause clearly and flag the offending drug in the record.
RoundsRx Infographic Series · #175 · Neurology · PDF 143 KB
Text version
Neurology · One Pager
PRES
Posterior Reversible Encephalopathy Syndrome: vasogenic edema from failed cerebral autoregulation, and it reverses only if you find and fix the trigger fast.
⚡ Triggers (Find One, Because Treating It Is the Treatment)
Severe hypertension: most common trigger, BP exceeds the upper limit of cerebral autoregulation
Eclampsia / pre-eclampsia: one of the most important causes in young women
Immunosuppressants: tacrolimus, cyclosporine (calcineurin inhibitors), common in transplant patients
Chemotherapy: especially VEGF inhibitors (bevacizumab)
Renal failure: especially with fluid overload plus hypertension
Note: PRES can occur at normal BP, especially drug-induced, so a normal blood pressure does not exclude it
🧪 Presentation and Diagnosis
Seizures (60 to 75%), the most common presenting symptom, then headache (50%), visual disturbance (cortical blindness, blurry vision, field defects, 33%), altered mental status (28%), and often severe hypertension. Acute to subacute over hours to days
MRI brain with FLAIR is the study of choice: bilateral, symmetric white matter edema in the posterior (occipital/parietal) regions, hyperintense on FLAIR and T2
DWI is what separates PRES from stroke: vasogenic edema is DWI normal or dark (no restricted diffusion); cytotoxic stroke edema is DWI bright with ADC dark. Restricted diffusion in PRES means progression to infarction, a poor prognostic sign
CT head is less sensitive and may be normal early. Use it to rule out hemorrhage, not to rule out PRES
Labs: BMP for renal function and electrolytes; CBC, LDH, smear, haptoglobin to exclude TTP/HUS if thrombocytopenic; urine protein/Cr if pregnant or postpartum; tacrolimus or cyclosporine trough if applicable
LP is typically not needed (CSF may show mild protein elevation), mainly to exclude meningitis or encephalitis if the diagnosis is uncertain
🚨 Management, Step by Step
1
TREAT THE CAUSE: this is the most important step and the reason the syndrome is reversible at all. Hypertensive emergency gets IV antihypertensives, eclampsia gets magnesium sulfate plus delivery, drug-induced gets the offending agent discontinued (tacrolimus, cyclosporine, chemotherapy)
2
Lower BP gradually, target a 25% reduction in MAP over the first few hours. Avoid precipitous drops because of the risk of ischemia. IV nicardipine or labetalol preferred
3
Seizure control: benzodiazepines for acute seizures, then levetiracetam for prophylaxis and maintenance because it has fewer drug interactions than phenytoin in transplant patients
4
Expect reversal: clinical and radiographic improvement typically within days to weeks if treated promptly. If it is not improving, reconsider the diagnosis
5
Understand the cost of delay: delayed treatment can lead to permanent infarction, hemorrhage, and death. The reversibility is conditional, not automatic
💊 Key Drugs
Nicardipine (BP control, preferred)5 mg/hr IV, titrate by 2.5 mg/hr q5 to 15 min, max 15 mg/hr
Labetalol (alternative)10 to 20 mg IV bolus, double q10 min to max 300 mg, or 1 to 2 mg/min drip
Lorazepam (Ativan), acute seizures2 to 4 mg IV PRN
Levetiracetam (Keppra), prophylaxis500 to 1000 mg IV/PO BID
Magnesium sulfate, eclamptic PRES4 to 6 g IV load, then 1 to 2 g/hr
📊 Monitoring
BP continuously (arterial line or frequent NIBP): target 25% MAP reduction over the first hours, then normalize gradually, because overshooting risks ischemia
Serial neuro checks q1 to 2h, documenting mental status, vision, and motor function, since these are what tell you the edema is resolving
Repeat MRI in 1 to 2 weeks to confirm radiographic resolution. If it is not improving, reconsider the diagnosis
Continuous EEG if altered mental status persists or seizures recur, to catch nonconvulsive activity
Calcineurin inhibitor trough levels if drug-related, and hold or reduce the dose until resolution
Urine output and renal function, especially when pre-eclampsia or renal failure is the trigger
⚠️ Pitfalls
Dropping the BP precipitously. The target is a 25% MAP reduction over hours, not normalization in minutes, because a fast drop causes ischemia
Trusting a normal CT. CT is less sensitive and may be normal early; MRI with FLAIR is what makes the diagnosis
Assuming the name is literal. PRES is not always posterior (frontal lobes, brainstem, cerebellum can be involved) and not always reversible
Excluding PRES because the BP is normal. Drug-induced PRES can occur at normal blood pressures
Reaching for phenytoin in a transplant patient. It induces CYP3A4, which metabolizes tacrolimus and cyclosporine, so immunosuppressant levels crash and the graft is at risk of rejection. Levetiracetam is renally cleared with no CYP interactions
Calling restricted diffusion "still PRES" and relaxing. It signals progression to infarction
🏥 Escalate / Act Immediately When
Seizure plus visual change plus severe hypertension: get the MRI, do not sit on it, because the window in which this is reversible is short
Transplant patient with a supratherapeutic calcineurin inhibitor trough: hold the drug, that is the trigger and removing it is the treatment
Pregnant or postpartum: eclampsia pathway, magnesium sulfate plus delivery, involve obstetrics immediately
Thrombocytopenia on the CBC: send LDH, smear, and haptoglobin to exclude TTP/HUS, which is a different emergency with a different treatment
Restricted diffusion, hemorrhage, or no improvement on repeat imaging: reconsider the diagnosis and escalate, this is no longer simple reversible PRES
🎓 The Core Concepts
Pathophysiology: failure of cerebral autoregulation leads to blood-brain barrier breakdown and vasogenic edema
Why posterior: the posterior (vertebrobasilar) circulation has less sympathetic innervation than the anterior (carotid) circulation, and sympathetic tone is what maintains autoregulation during acute hypertension, so the posterior circulation breaks through into hyperperfusion first
Why levetiracetam over phenytoin: phenytoin is metabolized by and induces CYP3A4, dramatically lowering tacrolimus and cyclosporine levels and risking acute rejection
The one-line takeaway: PRES is a clinical-radiographic diagnosis, and treating the trigger is what drives recovery
Misfolded protein deposition causing organ dysfunction. AL (light chain) is most common systemic type. Cardiac involvement = very poor prognosis. Classic clue: low voltage ECG + thick walls on echo. Diagnosis: Congo red stain with apple-green birefringence.
🔍 Overview
Overview
Amyloidosis is a group of diseases caused by extracellular deposition of misfolded proteins (amyloid fibrils) in tissues, leading to organ dysfunction. The protein type determines the disease subtype and treatment.
Major Types
AL Amyloidosis (Light Chain) -from plasma cell dyscrasia. Most common systemic amyloidosis. Light chains (usually lambda) misfold and deposit. Related to multiple myeloma but most patients do NOT have overt myeloma.
AA Amyloidosis -from serum amyloid A (SAA) protein, produced in chronic inflammation. Causes: RA, Crohn disease, familial Mediterranean fever (FMF), chronic infections. Predominantly affects kidneys.
ATTR Amyloidosis (Transthyretin) -hereditary (mutant TTR) or wild-type (senile cardiac amyloidosis). Increasingly recognized as a cause of HFpEF in elderly patients.
Organ Involvement
Heart -restrictive cardiomyopathy. Low voltage on ECG despite thick walls on echo (classic discordance). Diastolic dysfunction. Elevated troponin and BNP.
Tongue -macroglossia (pathognomonic for AL amyloidosis)
Low voltage on ECG + thick walls on echo = think amyloidosis. In HCM, thick walls produce HIGH voltage. This voltage-mass discordance is a classic board question. The amyloid infiltrates the myocardium, increasing wall thickness but reducing electrical signal.
🚨 Management
AL Amyloidosis
Treat the underlying plasma cell clone -goal is to eliminate the source of amyloidogenic light chains.
Autologous stem cell transplant (SCT) -for eligible patients (typically younger, no significant cardiac involvement). Best long-term outcomes.
Cardiac AL prognosis: Very poor -median survival 6 months untreated. With modern treatment, outcomes improving but cardiac involvement remains the dominant prognostic factor.
AA Amyloidosis
Treat the underlying inflammatory disease. Control RA, Crohn, FMF (colchicine for FMF). Reducing SAA levels can halt progression and even allow regression of amyloid deposits.
Supportive Care
Heart failure: Diuretics -use cautiously, these patients are preload-dependent (restrictive physiology). Small changes in volume cause dramatic hemodynamic effects. Avoid digoxin (binds amyloid fibrils, causing toxicity at therapeutic levels).
Orthostatic hypotension:Midodrine 5-10 mg TID, compression stockings, increased salt intake.
Nephrotic syndrome: ACEi/ARB for proteinuria. Diuretics for edema.
🧪 Workup
Diagnosis
Tissue biopsy with Congo red stain -apple-green birefringence under polarized light is diagnostic of amyloid.
Fat pad aspirate -least invasive biopsy site. Sensitivity ~70-80% for AL. If negative but suspicion high, biopsy the affected organ.
Bone marrow biopsy -to assess plasma cell clone in AL amyloidosis.
Typing the Amyloid
SPEP / UPEP / serum free light chains -for AL amyloidosis. Free light chain ratio is abnormal in >95% of AL patients.
SAA levels -for AA amyloidosis. Elevated in chronic inflammatory states.
Mass spectrometry -gold standard for amyloid subtyping (laser microdissection + mass spec on biopsy tissue).
Cardiac Assessment
Troponin and BNP/NT-proBNP -markedly elevated in cardiac amyloidosis. Used for staging (Mayo staging system).
ECG -low voltage (limb leads <5mm) + pseudo-infarct pattern (Q waves without MI) are classic.
Echocardiogram -thick walls + diastolic dysfunction. "Sparkling" or "granular" myocardium (sometimes described on older machines). Small LV cavity, biatrial enlargement.
Cardiac MRI -characteristic diffuse subendocardial or transmural late gadolinium enhancement pattern. Global T1 elevation.
Technetium pyrophosphate (PYP) scan -highly sensitive and specific for ATTR cardiac amyloidosis. Grade 2-3 uptake = diagnostic without biopsy.
💊 Medications
Medications
Drug
Type
Dose
Notes
Daratumumab (Darzalex) AL 1ST LINE
AL
16 mg/kg IV weekly x 8, then q2 weeks, then monthly
Anti-CD38 monoclonal antibody. Combined with CyBorD. ANDROMEDA, NEJM 2021
Bortezomib (Velcade)
AL
1.3 mg/m2 SQ weekly (part of CyBorD)
Proteasome inhibitor. Targets plasma cells. Peripheral neuropathy is dose-limiting toxicity.
Cyclophosphamide
AL
300 mg/m2 PO weekly (part of CyBorD)
Alkylating agent. Dose adjust for renal function.
Dexamethasone
AL
20-40 mg PO weekly (part of CyBorD)
Steroid component. Monitor glucose, infections.
Tafamidis (Vyndamax)
ATTR
80 mg PO daily
TTR stabilizer for ATTR cardiac amyloidosis. Reduced mortality and CV hospitalization. ATTR-ACT, NEJM 2018
Midodrine
Supportive
5-10 mg PO TID
For orthostatic hypotension from autonomic neuropathy. Hold if supine BP >180.
🏥 Rounds
Pimp Questions
❓ Why does amyloidosis cause low voltage on ECG despite thick walls on echo?
In HCM, the thick walls are due to myocyte hypertrophy, which increases electrical mass and produces high voltage. In amyloidosis, the thick walls are due to amyloid infiltration between myocytes -the amyloid protein is electrically inert and actually insulates the myocardium, reducing the electrical signal. This creates the classic voltage-mass discordance: thick walls + low voltage = amyloid (not HCM).
❓ Why is digoxin dangerous in cardiac amyloidosis?
Digoxin binds to amyloid fibrils in the myocardium, leading to tissue accumulation and toxicity even at "therapeutic" serum levels. Patients with cardiac amyloidosis are exquisitely sensitive to digoxin and can develop fatal arrhythmias. This is a classic pharmacology teaching point -always avoid digoxin in amyloid cardiomyopathy.
❓ What is the significance of macroglossia in amyloidosis?
Macroglossia is pathognomonic for AL amyloidosis -it does not occur in AA or ATTR types. Present in ~10-15% of AL patients. It is virtually diagnostic when seen in the right clinical context. Look for tooth indentations on the lateral tongue edges. Can also cause dysphagia and obstructive sleep apnea.
❓ How does the ANDROMEDA trial change AL amyloidosis treatment?
ANDROMEDA (NEJM 2021) showed that adding daratumumab (anti-CD38) to CyBorD (bortezomib, cyclophosphamide, dexamethasone) significantly improved hematologic complete response (53% vs 18%) and cardiac and renal organ response rates. Dara-CyBorD is now the standard first-line regimen for newly diagnosed AL amyloidosis.
Clinical Examples
📋 Case 1, AL Amyloidosis with Cardiac Involvement
Patient: 64M with progressive dyspnea, bilateral LE edema, and orthostatic hypotension. Echo: thick walls (IVS 16 mm), small LV cavity, diastolic dysfunction, EF 50%. ECG: low voltage + pseudo-infarct pattern. NT-proBNP 9200, troponin 0.18. Macroglossia on exam.
Key findings: Classic cardiac AL amyloidosis: thick walls + low voltage on ECG = pathognomonic discordance (hypertrophy causes high voltage, but amyloid infiltration causes low voltage). Macroglossia is virtually diagnostic for AL type.
Management:
Fat pad aspirate or organ biopsy → Congo red stain (apple-green birefringence under polarized light)
Mass spectrometry typing to confirm AL (vs ATTR), critical for treatment selection
Diuretics for volume overload, use cautiously (preload-dependent restrictive physiology). AVOID digoxin (binds to amyloid fibrils → toxicity at therapeutic levels)
Midodrine for orthostatic hypotension (autonomic neuropathy from amyloid infiltration)
Teaching point: The ECG-echo discordance (low voltage + thick walls) is the signature finding of cardiac amyloidosis. HCM and hypertensive heart disease cause thick walls WITH high voltage. If the walls are thick but voltage is low → think amyloid.
📋 Case 2, ATTR Cardiac Amyloidosis (Wild-Type)
Patient: 82M with HFpEF refractory to standard therapy. History of bilateral carpal tunnel surgery, lumbar spinal stenosis. Echo: concentric LVH (IVS 15 mm), grade III diastolic dysfunction. Technetium pyrophosphate scan: grade 3 uptake. SPEP/sFLC normal.
Key findings: Wild-type ATTR (ATTRwt), transthyretin amyloidosis from age-related misfolding. No plasma cell dyscrasia (SPEP/sFLC normal). Tc-PYP scan grade 2-3 = diagnostic for ATTR without biopsy (if SPEP/sFLC negative). Bilateral carpal tunnel + spinal stenosis are early manifestations.
No chemotherapy needed (ATTR is not a plasma cell disorder, no clonal cells to target)
Diuretics for congestion, careful volume management
Genetic testing: rule out hereditary ATTR (TTR gene mutations, affects family screening and transplant eligibility)
Avoid ACEi/ARB aggressively, often poorly tolerated due to restrictive physiology + autonomic dysfunction
Teaching point: ATTR is now recognized as a common cause of HFpEF in elderly men, prevalence may be 10-15% of HFpEF patients > 80. Bilateral carpal tunnel + HFpEF + thick walls should trigger Tc-PYP scan. Tafamidis is disease-modifying.
📋 Case 3, AL Amyloidosis with Nephrotic Syndrome
Patient: 58F with progressive LE edema, foamy urine. Albumin 1.8, 24h urine protein 8.2 g/day, Cr 1.6. sFLC: lambda 420 mg/L (elevated), ratio abnormal. Renal biopsy: Congo red positive in glomeruli and vessels.
Key findings: AL amyloidosis presenting as nephrotic syndrome (renal is the most common organ involved in AL). Lambda light chain predominance. Must assess cardiac involvement, asymptomatic cardiac amyloid can coexist.
Echo + ECG to assess subclinical cardiac involvement
Dara-CyBorD (standard first-line for AL amyloidosis regardless of organ involvement)
Aggressive diuresis for nephrotic edema (furosemide + metolazone). ACEi/ARB for proteinuria reduction
If young + fit + good cardiac function: consider autologous stem cell transplant after induction (high CR rates in selected patients)
Teaching point: In any patient with unexplained nephrotic syndrome + monoclonal protein, think AL amyloidosis. The combination of nephrotic-range proteinuria + abnormal sFLC ratio is the classic presentation. Always check cardiac biomarkers, occult cardiac involvement determines prognosis.
Sample Presentation
Mr. Franklin is a 62-year-old man presenting with 6 months of progressive dyspnea on exertion, lower extremity edema, and 15-lb weight loss. He also reports numbness/tingling in both feet and lightheadedness when standing. Exam: macroglossia, periorbital purpura, elevated JVP, bilateral pitting edema. Labs: troponin 0.15 (elevated), NT-proBNP 8,400 (markedly elevated), creatinine 1.8, albumin 2.1, 24h urine protein 5.2 g/day. ECG: low voltage + pseudo-infarct pattern. Echo: thick walls (IVS 16mm) + diastolic dysfunction + small LV cavity. Free kappa/lambda ratio markedly abnormal (lambda predominant). Fat pad biopsy: Congo red positive, apple-green birefringence under polarized light.
Key Points: Classic AL amyloidosis with multiorgan involvement -cardiac (restrictive CMP, low voltage + thick walls), renal (nephrotic syndrome), neurologic (peripheral and autonomic neuropathy), macroglossia (pathognomonic). Staging: elevated troponin + NT-proBNP = advanced cardiac involvement (Mayo Stage III). Start Dara-CyBorD. Diuretics for volume overload but use cautiously (preload-dependent). Midodrine for orthostatic hypotension. Avoid digoxin.
Monitoring
Serum free light chains -q1-3 months during treatment. Hematologic response: normalization of free light chain ratio.
NT-proBNP and troponin -cardiac biomarkers used for staging and monitoring organ response. Reduction indicates cardiac response.
24h urine protein -for renal involvement. Renal response: >50% reduction in proteinuria.
CBC, BMP -monitor for treatment toxicity (myelosuppression from chemo, renal function).
📋 Summary
Summary
What It Is
Misfolded protein deposits as insoluble fibrils and progressively stiffens organs.AL (light chain) is the commonest systemic type and comes from a clonal plasma cell disorder. ATTR is transthyretin, either hereditary or wild-type in older men. AA is serum amyloid A driven by chronic inflammation.
The Clue That Should Trigger the Thought
Low voltage on the ECG with thick walls on echo.In hypertrophic cardiomyopathy thick walls produce high voltage; here the myocardium is infiltrated rather than hypertrophied, so mass rises while voltage falls. That voltage-mass discordance is the single most useful bedside signal.
Other Presentations Worth Recognizing
Nephrotic-range proteinuria, heart failure with preserved ejection fraction, hepatomegaly out of proportion to liver tests, peripheral and autonomic neuropathy, and the specific signs: macroglossia and periorbital purpura, which are nearly exclusive to AL. Bilateral carpal tunnel syndrome years before the cardiac diagnosis is the classic early clue in ATTR.
Confirm With Tissue
Congo red staining with apple-green birefringence under polarized light.Abdominal fat pad aspirate is the least invasive first step; if negative and suspicion is high, biopsy the affected organ. Never stop at 'amyloid present', because the type determines the entire treatment.
Typing Is the Decision Point
Mass spectrometry on the tissue is the gold standard. Check serum and urine immunofixation with serum free light chains for a plasma cell clone. Assuming AL because a monoclonal protein is present is a real error: MGUS is common in the elderly and coexists with ATTR, and treating ATTR with chemotherapy helps nobody. A PYP scan diagnoses ATTR cardiac amyloid non-invasively once AL has been excluded.
Treat AL by Killing the Clone
Daratumumab added to CyBorD (cyclophosphamide, bortezomib, dexamethasone) is first line (ANDROMEDA). Autologous stem cell transplant in carefully selected patients. Response is tracked by the free light chain difference, not by symptoms, and organ recovery lags the hematologic response by months.
Treat ATTR by Stabilizing the Protein
Tafamidis 80 mg daily reduces mortality and cardiovascular hospitalization in ATTR cardiomyopathy (ATTR-ACT). Gene-silencing agents are used in hereditary ATTR polyneuropathy. Start early, because these agents stop further deposition but do not clear what is already there.
The Cardiac Drugs Behave Differently
Amyloid heart failure is a restrictive, preload-dependent physiology, so standard heart failure therapy can do harm.Beta blockers and ACE inhibitors are often poorly tolerated and cause hypotension. Avoid digoxin and calcium channel blockers, which bind to amyloid fibrils and are prone to toxicity. Diuretics are the mainstay. Cardiac involvement is the dominant prognostic factor, which is why staging uses troponin and NT-proBNP.
RoundsRx Infographic Series · #161 · Hematology · PDF 144 KB
Text version
HEME / ONC · One Pager
Amyloidosis
Extracellular deposition of misfolded protein. Congo red proves it is amyloid, but the protein type is what determines the disease and the treatment, so typing the tissue is not an academic step, it is the whole decision.
🧪 The Subtypes Drive Everything
AL (light chain): from a plasma cell dyscrasia. The most common systemic amyloidosis. Light chains, usually lambda, misfold and deposit. Related to multiple myeloma, but most patients do not have overt myeloma, so a normal marrow does not exclude it. Treatment targets the clone.
ATTR (transthyretin), hereditary: mutant TTR. Genetic testing matters here because it changes family screening and transplant eligibility, not just the label.
ATTR, wild-type (ATTRwt, senile cardiac amyloidosis): age-related TTR misfolding with no plasma cell clone. Increasingly recognized as a cause of HFpEF in elderly patients; prevalence may be 10–15% of HFpEF patients > 80. Bilateral carpal tunnel surgery and lumbar spinal stenosis are early manifestations that precede the heart failure by years.
AA: from serum amyloid A (SAA) produced in chronic inflammation. Causes: RA, Crohn disease, familial Mediterranean fever, chronic infections. Predominantly affects the kidneys. Treatment is control of the inflammatory driver, not chemotherapy.
Do not blur AL and ATTR. AL gets chemotherapy; ATTR has no clone to target and gets a TTR stabilizer. Getting this backwards means either useless chemotherapy or an untreated fatal plasma cell disease.
⚡ Organ Clues That Should Trigger the Thought
Heart, restrictive cardiomyopathy:low voltage on ECG despite thick walls on echo, the classic voltage-mass discordance. In HCM and hypertensive heart disease, thick walls produce high voltage because the thickness is myocyte hypertrophy. In amyloid, the thickness is electrically inert protein infiltrating between myocytes, which insulates the myocardium.
Kidney: nephrotic syndrome, proteinuria, edema, hypoalbuminemia. Unexplained nephrotic syndrome plus a monoclonal protein is AL until proven otherwise.
Tongue, macroglossia:pathognomonic for AL, present in roughly 10–15% of AL patients and does not occur in AA or ATTR. Look for tooth indentations on the lateral tongue edges; it can also cause dysphagia and obstructive sleep apnea.
Nerves: peripheral neuropathy (pain, numbness) and autonomic neuropathy (orthostatic hypotension). The orthostasis is not just deconditioning.
Liver: hepatomegaly with elevated alkaline phosphatase.
GI: malabsorption, weight loss, GI bleeding.
🚨 Diagnostic Sequence: Prove It, Then Type It
1
Prove amyloid is present: tissue biopsy with Congo red stain showing apple-green birefringence under polarized light. Start with fat pad aspirate, the least invasive site, sensitivity ~70–80% for AL. If it is negative and suspicion stays high, biopsy the affected organ, because a negative fat pad does not rule out disease.
2
Type the amyloid, this is the step that decides treatment.Mass spectrometry (laser microdissection plus mass spec on biopsy tissue) is the gold standard for subtyping.
3
Screen for the plasma cell clone: SPEP, UPEP, and serum free light chains. The free light chain ratio is abnormal in > 95% of AL patients, which is what makes a normal sFLC and SPEP so useful for pointing toward ATTR instead. Bone marrow biopsy assesses the clone in AL. Check SAA if the picture suggests AA.
4
Assess the heart in everyone, because occult cardiac involvement determines prognosis. Troponin and BNP/NT-proBNP are markedly elevated and are used for Mayo staging. ECG: low voltage (limb leads < 5 mm) plus pseudo-infarct pattern (Q waves without MI). Echo: thick walls, diastolic dysfunction, small LV cavity, biatrial enlargement, "sparkling" or granular myocardium. Cardiac MRI: diffuse subendocardial or transmural late gadolinium enhancement with global T1 elevation.
5
Technetium pyrophosphate (PYP) scan when ATTR is on the table: highly sensitive and specific for ATTR cardiac amyloidosis, and grade 2–3 uptake is diagnostic without biopsy. In hereditary versus wild-type ATTR, send TTR genetic testing, since a mutation changes family screening and transplant eligibility.
💊 Key Drugs by Subtype
Daratumumab (Darzalex)AL first-line: 16 mg/kg IV weekly × 8, then q2 weeks, then monthly; anti-CD38, combined with CyBorD
Bortezomib (Velcade)AL: 1.3 mg/m² SQ weekly as part of CyBorD; proteasome inhibitor, peripheral neuropathy is dose-limiting
CyclophosphamideAL: 300 mg/m² PO weekly as part of CyBorD; dose adjust for renal function
DexamethasoneAL: 20–40 mg PO weekly as part of CyBorD; monitor glucose and infections
Tafamidis (Vyndamax)ATTR: 80 mg PO daily; TTR stabilizer that reduced mortality and CV hospitalization in ATTR cardiomyopathy
MidodrineSupportive: 5–10 mg PO TID for orthostatic hypotension from autonomic neuropathy; hold if supine BP > 180
ColchicineAA from familial Mediterranean fever; controlling the inflammatory driver lowers SAA
Autologous stem cell transplantAL, for eligible patients (typically younger, no significant cardiac involvement); best long-term outcomes
📊 Monitoring
Serum free light chains q1–3 months during treatment. Hematologic response means normalization of the free light chain ratio, and it moves before organ function does.
NT-proBNP and troponin for staging and organ response; a reduction indicates cardiac response, the response that matters most for survival.
24h urine protein for renal involvement. Renal response is defined as a > 50% reduction in proteinuria.
ALP for hepatic involvement; hepatic response is a > 50% decrease.
Echocardiogram q6–12 months to track wall thickness, diastolic function, and strain patterns.
Orthostatic vitals to follow autonomic neuropathy and titrate midodrine.
CBC and BMP for treatment toxicity: myelosuppression from chemotherapy and renal function.
⚠️ Pitfalls
Digoxin in cardiac amyloidosis. It binds amyloid fibrils and accumulates in tissue, producing toxicity and potentially fatal arrhythmias at "therapeutic" serum levels. Avoid it entirely.
Aggressive diuresis. Restrictive physiology makes these patients preload-dependent, so small volume changes cause dramatic hemodynamic effects. Diurese, but cautiously.
Reading thick walls as HCM or hypertensive heart disease. Thick walls with low voltage is amyloid; thick walls with high voltage is hypertrophy.
Skipping the typing step. Congo red only says "amyloid". Committing an ATTR patient to chemotherapy, or an AL patient to tafamidis alone, follows directly from that shortcut.
Calling a PYP scan diagnostic while the clone workup is still open. Grade 2–3 uptake confirms ATTR without biopsy only when SPEP and sFLC are negative, since a coexisting monoclonal protein reopens the AL question.
Assuming no myeloma means no AL. Most AL patients do not have overt myeloma.
Assuming renal-only disease. Asymptomatic cardiac amyloid can coexist and determines prognosis, so check cardiac biomarkers even when the presentation is purely nephrotic.
Pushing ACEi/ARB hard in ATTR cardiac amyloid; they are often poorly tolerated because of restrictive physiology plus autonomic dysfunction.
🏥 Treatment by Subtype, and When to Escalate
AL: treat the underlying plasma cell clone to eliminate the source of amyloidogenic light chains. First-line is Dara-CyBorD (daratumumab plus cyclophosphamide, bortezomib, dexamethasone), regardless of which organ is involved.
AL, transplant-eligible: autologous stem cell transplant for younger, fit patients without significant cardiac involvement, which gives the best long-term outcomes; consider after induction.
Cardiac AL is the prognostic driver: median survival 6 months untreated. Elevated troponin plus NT-proBNP means advanced cardiac involvement by Mayo staging and should accelerate, not delay, referral.
ATTR: tafamidis 80 mg daily. No chemotherapy, there is no clonal cell population to target.
AA: treat the underlying inflammatory disease (RA, Crohn, FMF with colchicine). Lowering SAA can halt progression and even allow regression of deposits, which is why disease control is the therapy.
New complete heart block, syncope, or refractory heart failure: cardiology involvement; restrictive physiology limits standard HF therapy.
Bilateral carpal tunnel syndrome plus HFpEF plus thick walls in an older patient: order the Tc-PYP scan rather than continuing to titrate diuretics.
🎓 Key Evidence
ANDROMEDA, NEJM 2021: adding daratumumab to CyBorD in newly diagnosed AL doubled the hematologic complete response (53% vs 18%) and improved cardiac and renal organ response. Dara-CyBorD is now the first-line standard.
ATTR-ACT, NEJM 2018: tafamidis reduced all-cause mortality and cardiovascular hospitalization in ATTR cardiomyopathy, making it genuinely disease-modifying rather than supportive.
Mayo staging using troponin and NT-proBNP is what converts "cardiac involvement" into a prognosis and a treatment intensity, so send both at diagnosis.
Classic triad: hypoxemia + neurological changes + petechial rash, occurring 24-72h after long bone fractures. Clinical diagnosis with no definitive lab test. Treatment is supportive. The petechial rash is the most specific finding but appears in only ~50% of cases.
🔍 Overview
Overview
Fat embolism syndrome (FES) occurs when fat globules enter the venous system, leading to pulmonary and systemic embolization with an inflammatory cascade. Classic triad: (1) hypoxemia/respiratory distress, (2) neurological changes (confusion, AMS), (3) petechial rash. Onset is typically 24-72 hours after the inciting event. Incidence: up to 10% of long bone fractures, but clinically significant FES is less common (~1-3%).
Causes
Long bone fractures -most common cause, especially femur and tibia
Orthopedic surgery -intramedullary nailing, joint arthroplasty
Multiple fractures / polytrauma -risk increases with number of fractures
Fat globules from bone marrow enter the venous system through disrupted medullary vessels. In the lungs, fat is hydrolyzed by lipase into free fatty acids, which cause endothelial damage, inflammation, and increased capillary permeability (chemical pneumonitis). Fat also passes through the pulmonary vasculature or a PFO into systemic circulation, causing CNS and skin manifestations.
Risk Stratification -Who Gets FES?
Risk tier
Mechanism / patient profile
Approximate FES incidence
Highest risk
Bilateral femur fractures · multiple long bone fractures · pelvic fracture + femur · intramedullary nailing without venting · younger adult (20-40 yo, more marrow fat) · closed fracture (pressurizes the canal) · delay to fixation > 24-48 h
5-10% clinically significant
Moderate risk
Single femur fracture · tibia fracture · hip fracture in elderly · IM nailing of single long bone · joint arthroplasty (especially THA, TKA) · liposuction
Both can hit the same patient. A trauma patient with hypoxemia post-fracture could have PE, FES, or both -plus aspiration, pneumonia, or ARDS. Use the table below; always rule out PE with CTPA because the treatments are dramatically different (anticoagulation for PE, supportive only for FES).
Feature
Fat Embolism Syndrome (FES)
Pulmonary Embolism (PE)
Timing post-fracture
24-72 h (peaks 48 h)
Usually > 3-5 days, but can occur any time post-immobilization
CT-PA findings
NO filling defects. May show diffuse ground-glass / "snowstorm" pattern.
Filling defects in pulmonary arteries (lobar, segmental, or subsegmental)
Petechial rash
YES (chest, axillae, conjunctivae) -only ~50% of cases but specific
Early fracture fixation -reduces ongoing fat embolization. Definitive surgical fixation within 24h when possible.
Supportive ICU care -vasopressors if hemodynamically unstable, seizure management if needed.
Prevention
Early fracture stabilization -most important preventive measure. External fixation or definitive internal fixation within 24h reduces FES incidence.
Corticosteroids for PREVENTION:Methylprednisolone 1.5 mg/kg IV q8h x 3 doses before surgery -some evidence of benefit in high-risk patients (bilateral femur fractures, polytrauma). Not universally adopted due to mixed trial results. Schonfeld, Ann Intern Med 1983
Fat embolism syndrome is a CLINICAL diagnosis -there is no definitive lab test. The triad of hypoxemia + neurological changes + petechial rash 24-72h after a long bone fracture is classic. The petechial rash (non-palpable, typically on chest, axillae, and conjunctivae) is the most specific finding but appears in only ~50% of cases. Gurd criteria are commonly referenced.
🧪 Workup
Diagnostic Workup
FES is a clinical diagnosis. No single test is diagnostic. The following support the diagnosis:
ABG -hypoxemia (PaO2 <60 mmHg). Often the earliest finding.
CXR -bilateral diffuse infiltrates, "snowstorm" pattern. May take 12-24h to develop. Non-specific.
Bronchoalveolar lavage (BAL) -may show fat-laden macrophages (oil red O stain), but this finding is NOT specific for FES (can occur in other conditions).
MRI brain -if neurological symptoms prominent. May show "starfield" pattern of punctate T2/FLAIR bright lesions (microembolic infarcts).
Gurd Criteria (Clinical Diagnosis)
Requires at least 1 major + 4 minor criteria, OR 2 major criteria:
Minor: Tachycardia, fever, retinal changes, fat in urine, thrombocytopenia, elevated ESR, fat globules in sputum
Schonfeld Score (Alternative -Quantitative) -fat embolism syndrome diagnosis (more sensitive than Gurd in mild/moderate cases)
Sum of weighted findings; ≥ 5 points = FES diagnosis. More sensitive than Gurd in mild/moderate cases.
Finding
Points
Petechiae
5
Diffuse infiltrates on CXR
4
Hypoxemia (PaO₂ < 70 mmHg)
3
Confusion / AMS
1
Fever > 38°C
1
Heart rate > 120 bpm
1
Respiratory rate > 30/min
1
Gurd vs Schonfeld: Gurd is the classic / boards-tested criteria but is relatively specific (misses milder cases). Schonfeld weights petechiae and CXR findings more heavily and catches subclinical FES. Most clinicians still cite Gurd; use Schonfeld when Gurd seems too restrictive in a high-suspicion case.
When fat globules cross the pulmonary capillary bed (or shunt through a patent foramen ovale), they reach the systemic circulation and lodge in cerebral microvasculature. Cerebral fat embolism (CFE) can occur with or without prominent pulmonary findings -occasionally as the dominant presentation.
Presentation: confusion, agitation, seizures, focal deficits (hemiparesis, aphasia), coma in severe cases. Can mimic stroke.
Onset: usually 12-72 h post-injury, often before petechiae or hypoxemia become prominent.
MRI findings: the pathognomonic "starfield" pattern -multiple small punctate T2 / FLAIR / DWI hyperintensities scattered throughout subcortical white matter, basal ganglia, cerebellum, and corpus callosum. Highly specific for CFE in the right clinical context.
EEG: diffuse slowing, may show non-convulsive seizures.
Patent foramen ovale (PFO): identified in ~25% of severe CFE cases. Echo with bubble study can reveal right-to-left shunt.
Prognosis: CFE often has good recovery with supportive care if patient survives the acute phase. Most neuro deficits resolve over weeks to months. Persistent cognitive deficits in severe cases.
Treatment: SUPPORTIVE -airway protection, seizure management (levetiracetam preferred), maintain cerebral perfusion (MAP 65-70). No specific therapy.
CFE may present BEFORE the classic triad develops. A young trauma patient with bilateral femur fractures who develops sudden confusion or focal neuro deficits 12-48 h post-injury -think CFE before stroke. Get an urgent MRI; the starfield pattern is diagnostic. CT will usually be normal (lesions too small) and shouldn't reassure you.
💊 Medications
Medications
Drug
Indication
Dose
Notes
Methylprednisolone
Prevention (high-risk)
1.5 mg/kg IV q8h x 3 doses preop
Some evidence for prophylaxis in high-risk long bone fractures. Not universally adopted. Start before surgical fixation. Schonfeld, Ann Intern Med 1983
Heparin
VTE prophylaxis
5000 units SQ q8h or enoxaparin 40 mg SQ daily
Standard VTE prophylaxis in trauma patients. Does NOT treat FES specifically, but prevents concomitant VTE.
Norepinephrine
Hemodynamic support
0.1-2 mcg/kg/min IV
If hypotension from RV failure or distributive shock component. Titrate to MAP >65.
Levetiracetam (Keppra)
Seizure management
500-1000 mg IV BID
If seizures from cerebral fat embolism. No specific seizure prophylaxis indicated without seizure activity.
Note: Treatment is predominantly supportive. No specific pharmacotherapy has proven benefit for established FES.
🏥 Rounds
Pimp Questions
❓ What is the classic timing and distribution of the petechial rash in FES?
The rash appears 24-72 hours after the fracture and is characteristically found on the chest, axillae, and conjunctivae -areas with high capillary density. The petechiae are non-palpable (unlike vasculitis) and often transient (may disappear within 24-48h). While the most specific finding, petechiae appear in only ~50% of FES cases and can be easily missed if not specifically examined for.
❓ How do you distinguish fat embolism from PE in a trauma patient?
Both can cause hypoxemia post-fracture. Key differences: (1) Timing -PE usually >3-5 days; FES 24-72h, (2) CT-PA -PE shows filling defects; FES shows NO filling defects, (3) Rash -petechial rash is specific to FES, (4) Thrombocytopenia and anemia -more characteristic of FES, (5) AMS -more prominent in FES (cerebral fat emboli). CT-PA should be obtained to rule out PE, as treatments differ dramatically.
❓ Why does early fracture fixation reduce fat embolism risk?
Unstabilized fractures allow ongoing release of fat and marrow contents from the disrupted bone into the venous system with every movement. Early fixation stabilizes the fracture site, reducing mechanical disruption and ongoing fat release. The ETC (Early Total Care) concept -definitive fixation within 24h -has been shown to reduce FES incidence, ARDS, and multiorgan failure in trauma patients.
❓ Why are bilateral femur fractures the highest risk for FES?
The femur has a large medullary cavity with abundant fat and marrow. Bilateral femur fractures double the amount of exposed marrow and fat available for embolization. The volume of fat released correlates with FES severity. Risk increases further with intramedullary reaming during nailing (pressurizes the canal, forcing fat into the venous system). Some surgeons use reamed nailing with venting to reduce this risk.
Sample Presentation
Mr. Rodriguez is a 24-year-old man admitted 48 hours ago after a motor vehicle collision with bilateral femoral shaft fractures, now s/p external fixation. Overnight he developed acute respiratory distress, confusion, and tachycardia. VS: T 38.5, HR 122, RR 28, BP 110/70, SpO2 82% on RA. Exam: confused, GCS 13 (E3V4M6), petechial rash across the chest and bilateral axillae, bilateral crackles on lung exam. Labs: PaO2 52 on ABG, platelets dropped from 210 to 98, Hgb from 11 to 8.5. CXR: bilateral diffuse infiltrates. CT-PA negative for PE.
Key Points: Classic fat embolism syndrome -classic triad of hypoxemia + AMS + petechial rash, onset 48h after bilateral femur fractures. CT-PA negative rules out PE. Treatment is SUPPORTIVE: high-flow O2 or intubation if worsening (PaO2 52), IVF resuscitation, trending platelets and neurologic status. Plan for definitive fracture fixation (intramedullary nailing) once stabilized. Most cases self-resolve within 72h with supportive care.
Monitoring
Continuous pulse oximetry -hypoxemia is often the earliest sign. O2 sat drop in a trauma patient 24-72h post-fracture should raise suspicion.
ABG -q6-12h if developing respiratory failure. Monitor for worsening hypoxemia and need for escalation.
CBC q12h -trending platelets (thrombocytopenia) and hemoglobin (hemolysis). Nadir typically at 48-72h.
Neurologic exam -serial assessments. AMS can range from confusion to coma. GCS trending.
CXR daily -track bilateral infiltrates. Monitor for progression to ARDS.
Skin exam -check chest, axillae, conjunctivae for petechiae q shift. Often transient (may last only 24-48h).
Urine output -monitor for renal dysfunction. Fat emboli can cause AKI.
📋 Summary
Summary
The Classic Presentation
Hypoxemia, neurologic changes and a petechial rash appearing 24 to 72 h after a long bone or pelvic fracture.The latency is the diagnostic clue: immediate post-injury hypoxemia is usually something else, and the 24 to 72 h window fits the inflammatory phase of fat embolism rather than the mechanical one.
The Rash Is Specific But Uncommon
Non-palpable petechiae over the axillae, conjunctivae, neck and chest.It is the most specific finding and it appears in only about half of cases, so its absence proves nothing. Look under the arms and at the conjunctivae deliberately, since it is easily missed on a routine trauma exam.
There Is No Confirmatory Test
Fat embolism syndrome is a clinical diagnosis.Gurd criteria are the classic framework, requiring one major (petechial rash, hypoxemia, central nervous system depression, pulmonary edema) plus minor criteria such as tachycardia, fever, retinal fat emboli, thrombocytopenia, anemia and a raised ESR. Gurd is specific and misses milder disease; Schonfeld weights petechiae and chest x-ray changes more heavily and catches subclinical cases.
Always Rule Out Pulmonary Embolism
Both hit the same patient, and the treatments differ dramatically.Get the CT pulmonary angiogram: anticoagulating fat embolism has no benefit, and missing a PE in a trauma patient is fatal. Aspiration, pneumonia and ARDS are also on the list. Fat embolism favors a normal CTPA with diffuse ground-glass change, a delayed onset and neurologic and dermatologic findings that a PE does not produce.
Treatment Is Supportive Only
Oxygen, lung-protective ventilation if intubated, hemodynamic support and time.Steroids are not established as treatment and there is no specific therapy. Heparin does not treat it and, by raising lipase activity and free fatty acid release, is theoretically harmful. Most patients recover over days to weeks with organ support alone.
Prevention Is Where the Leverage Is
Early operative fixation of long bone fractures, within 24 h, substantially reduces the incidence, because it stops the ongoing release of marrow contents. Careful reaming technique and limiting intramedullary pressure during nailing reduce the embolic load. Adequate resuscitation and oxygenation matter more than any drug.
Cerebral Fat Embolism Looks Different
It can present with confusion, seizures, focal deficits or coma with only mild hypoxemia, so the absence of respiratory failure does not exclude it. MRI shows a 'starfield' pattern of scattered punctate diffusion-restricting lesions, which is characteristic. The neurologic outcome is usually good with supportive care, so an alarming early exam should not drive prognostic pessimism.
Know Who Is at Risk
Closed long bone fractures, especially femoral shaft, and pelvic fractures; multiple fractures; intramedullary nailing and joint arthroplasty.Young adults with closed femoral fractures are the classic group, because they have marrow that is fatty and fractures that are high energy. Rarer non-traumatic causes include pancreatitis, sickle cell crisis with bone marrow necrosis, and liposuction.
Rare but lethal pharmacogenetic disorder triggered by volatile anesthetics or succinylcholine. Rising ETCO2 is the earliest sign. Dantrolene is the ONLY specific treatment. Mortality exceeds 70% without treatment, but drops below 5% with early dantrolene.
🔍 Overview
Overview
Malignant hyperthermia (MH) is a rare, life-threatening pharmacogenetic disorder caused by mutations in the RYR1 gene (ryanodine receptor on sarcoplasmic reticulum). Triggered by volatile anesthetics (sevoflurane, desflurane, isoflurane) or succinylcholine. The mutation causes uncontrolled calcium release from the sarcoplasmic reticulum into the myoplasm, leading to sustained muscle contraction, hypermetabolism, and multi-organ failure.
RYR1 mutation causes defective ryanodine receptor on skeletal muscle sarcoplasmic reticulum. Triggering agent causes uncontrolled calcium release into myoplasm, leading to sustained muscle contraction, exponentially increased oxygen consumption and CO2 production, massive ATP hydrolysis, and heat generation. This cascade produces hypercarbia, metabolic acidosis, rhabdomyolysis, hyperkalemia, and eventually cardiac arrest if untreated.
Masseter spasm (trismus after succinylcholine), may be the first clinical sign
Rapidly rising temperature, can reach >40°C in minutes (1-2°C every 5 min). Temperature rise is often a LATE sign.
Muscle rigidity, generalized ("board-like")
Tachycardia, tachypnea, if spontaneously breathing
Metabolic acidosis, severe mixed respiratory and metabolic
Hyperkalemia, from rhabdomyolysis and cellular lysis
Rhabdomyolysis, CK >20,000 IU/L, dark urine (myoglobinuria)
DIC, late complication
Cardiac arrhythmias, from hyperkalemia, acidosis, and hyperthermia
🚨 Management
Immediate Management
STOP all triggering agents IMMEDIATELY. Discontinue volatile anesthetic. Turn off vaporizer. Disconnect circuit from anesthesia machine. Hyperventilate with 100% O2 at high fresh gas flows (>10 L/min). Do NOT waste time changing the circuit, just flush with high-flow O2.
Dantrolene (Dantrium) 2.5 mg/kg IV push, repeat every 5 minutes until symptoms resolve. No maximum dose in an emergency (typically up to 10 mg/kg total, but more may be needed).
Call for HELP, you need multiple people to mix dantrolene.
Active cooling: ice packs to groin/axillae/neck, cold IV normal saline, cooling blankets, iced gastric/bladder lavage if refractory. Target temp <38.5°C, then STOP active cooling (risk of overshoot hypothermia).
Treat hyperkalemia: calcium gluconate 30 mL of 10% IV (or calcium chloride 10 mL), insulin 10 units + D50 50 mL IV, sodium bicarbonate 1-2 mEq/kg. Do NOT use succinylcholine for intubation.
Treat acidosis: sodium bicarbonate 1-2 mEq/kg IV for pH <7.2.
Treat arrhythmias: amiodarone for VT. Do NOT use calcium channel blockers (fatal interaction with dantrolene causing hyperkalemia and cardiovascular collapse).
Dantrolene is the ONLY specific treatment. Every OR must have it stocked. Know where it is BEFORE you need it. Each vial is 20 mg, a 70 kg patient needs ~9 vials for the first dose. It takes time to reconstitute (each vial requires 60 mL sterile water), call for help immediately. Newer formulations (Ryanodex) come as 250 mg/vial requiring only 5 mL to reconstitute.
Clinical Example: A 25-year-old male undergoing appendectomy under general anesthesia with sevoflurane. 30 minutes into the case, the anesthesiologist notices ETCO2 climbing from 38 to 72 despite increasing minute ventilation. HR jumps to 130. Jaw is rigid. Temperature probe shows 39.2°C and rising. This is MH until proven otherwise, STOP sevoflurane, call for dantrolene, hyperventilate with 100% O2, and begin active cooling.
🧪 Workup
Diagnostic Workup
MH is a clinical diagnosis in the acute setting. Do not delay treatment for labs.
ETCO2, earliest sign in the OR. Rising unexpectedly despite adequate ventilation.
ABG, severe mixed metabolic and respiratory acidosis (pH <7.2, pCO2 >60, base deficit >-8, lactate elevated)
CK (creatine kinase), massively elevated (>20,000 IU/L). Peaks at 12-24h. Serial CK q6h.
BMP, hyperkalemia (from rhabdomyolysis), initially hypercalcemia then hypocalcemia, renal function (AKI from myoglobinuria)
Myoglobin, serum and urine. Dark/cola-colored urine = myoglobinuria.
Core temperature, continuous monitoring (esophageal or rectal preferred)
Post-Crisis, Confirmatory Testing
Caffeine-halothane contracture test (CHCT), gold standard for MH susceptibility. Requires a muscle biopsy (usually vastus lateralis). Performed at specialized MH centers. Sensitivity ~97%, specificity ~78%.
Genetic testing, RYR1 mutation analysis. If positive, confirms susceptibility. But a negative result does NOT rule it out (only ~50-70% of MH families have identifiable mutations).
Screen first-degree relatives, autosomal dominant inheritance with variable penetrance.
💊 Medications
Medications
Drug
Indication
Dose
Notes
Dantrolene (Dantrium)
SPECIFIC treatment for MH
2.5 mg/kg IV push, repeat q5min PRN
No max dose in crisis. Each 20 mg vial needs 60 mL sterile water to reconstitute. Typical total 10 mg/kg. Continue 1 mg/kg IV q6h x 24-48h after crisis to prevent recrudescence.
Dantrolene (Ryanodex)
Newer formulation
2.5 mg/kg IV push
250 mg/vial, reconstitutes in only 5 mL. Much faster preparation. Single vial may cover initial dose for most patients.
Calcium gluconate 10%
Hyperkalemia cardioprotection
30 mL (3 amps) IV over 5-10 min
Stabilizes cardiac membrane. Does not lower K+.
Regular insulin + D50
Hyperkalemia treatment
10 units insulin IV + 50 mL D50
Drives K+ intracellularly. Check glucose q1h.
Sodium bicarbonate
Severe acidosis / hyperK
1-2 mEq/kg IV
For pH <7.2. Also helps drive K+ intracellularly.
Amiodarone
Ventricular arrhythmias
150 mg IV over 10 min, then 1 mg/min
For VT/VF. Do NOT use calcium channel blockers (lethal interaction with dantrolene).
NEVER use calcium channel blockers (verapamil, diltiazem) with dantrolene, combination causes fatal hyperkalemia and cardiovascular collapse. Use amiodarone or lidocaine for arrhythmias instead.
🏥 Rounds
Pimp Questions
❓ What is the earliest sign of malignant hyperthermia in the OR?
Rising ETCO2 (end-tidal CO2). This is often the earliest and most sensitive sign, reflecting the massive hypermetabolic state and increased CO2 production. Temperature elevation is often a LATE sign. The ETCO2 may rise to >60-80 mmHg despite adequate ventilation.
❓ What is the underlying mechanism of malignant hyperthermia?
Uncontrolled calcium release from the sarcoplasmic reticulum via defective ryanodine receptors (RYR1 mutation). The massive intracellular calcium causes sustained muscle contraction, ATP depletion, heat generation, and a hypermetabolic state with exponentially increased O2 consumption and CO2 production.
❓ Can you use succinylcholine for intubation in a patient with known MH susceptibility?
NO. Succinylcholine is a known trigger for MH. Use rocuronium (non-depolarizing agent) instead. Rocuronium can be reversed with sugammadex. All non-depolarizing neuromuscular blockers are safe in MH-susceptible patients.
Sample Presentation
Mr. Thompson is a 32-year-old male undergoing laparoscopic cholecystectomy under general anesthesia with sevoflurane. 45 minutes into the case, ETCO2 rose from 36 to 78 mmHg despite increasing minute ventilation. HR 142, BP 90/60. Jaw rigidity noted. Temperature probe: 39.8°C and rising rapidly. Volatile anesthetic was immediately discontinued, hyperventilation with 100% O2 initiated, and dantrolene 2.5 mg/kg IV push was given. After 3 doses (total 7.5 mg/kg), ETCO2 began trending down. Active cooling with ice packs and cold NS achieved temp <38.5°C. Labs: CK 45,000, K+ 6.8, pH 7.12, lactate 14. Treated hyperK with calcium, insulin/glucose, and bicarb. Now in ICU on dantrolene 1 mg/kg q6h.
Key Points: Classic MH presentation triggered by sevoflurane. Rising ETCO2 was the earliest sign. Immediate dantrolene was life-saving. Now monitoring for recrudescence (25% risk within 24-36h), renal injury from rhabdomyolysis (CK 45,000, targeting UOP >2 mL/kg/h), and DIC. Will need genetic counseling and screening of first-degree relatives.
Monitoring
Continuous ETCO2, most sensitive early indicator. Target normalization (<40 mmHg).
Core temperature, continuous (esophageal or rectal). Target <38.5°C. Stop active cooling at 38°C to prevent overshoot.
ABG q30-60 min during acute crisis, trend pH, pCO2, lactate, K+.
CK q6h x 24h, peak at 12-24h. If >10,000, aggressive IV hydration for renal protection.
Urine output, target >2 mL/kg/h to prevent myoglobin-induced AKI. Consider mannitol or bicarb drip if myoglobinuria.
Monitor for recrudescence, MH can recur in 25% of cases within 24-36h. Continue dantrolene 1 mg/kg q6h x 24-48h. Keep in monitored bed (ICU).
📋 Summary
Summary
Know the Triggers
Volatile anesthetics (halothane, sevoflurane, isoflurane, desflurane) and succinylcholine.Nothing else triggers it: nitrous oxide, propofol, ketamine, opioids, benzodiazepines and non-depolarizing paralytics are all safe. It is an autosomal dominant ryanodine receptor disorder, so ask about anesthetic problems in relatives, not only in the patient.
Rising End-Tidal CO2 Is the Earliest Sign
An unexplained, rising ETCO₂ that does not respond to increased minute ventilation is the first and most sensitive indicator.Fever is a late sign, so waiting for hyperthermia to make the diagnosis wastes the window in which dantrolene works. Masseter spasm after succinylcholine, tachycardia, rigidity and mixed acidosis follow.
Stop the Trigger Immediately
Discontinue the volatile agent, turn off the vaporizer, and hyperventilate with 100% oxygen at fresh gas flows above 10 L/min.Do not waste time changing the anesthesia circuit or the machine: high flows wash the agent out faster than a swap, and the delay costs more than the residual vapor. Call for help and get the MH cart.
Dantrolene Is the Only Specific Treatment
2.5 mg/kg IV rapidly, repeated every 5 to 10 min until the ETCO₂, rigidity and tachycardia settle, with no real ceiling in a crisis. Mortality exceeds 70% untreated and falls below 5% with early dantrolene.Know where it is stocked before you need it: the standard formulation is 20 mg per vial, so a 70 kg patient needs about 9 vials for the first dose alone, and each vial has to be reconstituted, which is why several people are needed just to mix it.
Never Give a Calcium Channel Blocker With Dantrolene
Verapamil or diltiazem with dantrolene causes fatal hyperkalemia and cardiovascular collapse.Use amiodarone or lidocaine for arrhythmias instead, and treat the underlying hyperkalemia and acidosis, which are usually what is driving the rhythm.
Cool and Correct in Parallel
Active cooling with cold IV fluids, ice packs to the groin and axillae, and lavage if needed; stop at about 38°C to avoid overshoot.Treat hyperkalemia aggressively with calcium, insulin and dextrose, and bicarbonate. Treat the rhabdomyolysis with aggressive fluids targeting a urine output of 1 to 2 mL/kg/h, and follow CK and myoglobin.
Watch Them for 24 to 48 Hours
Recrudescence occurs in up to a quarter of patients, typically within the first 24 h, which is why these patients go to the ICU on continued dantrolene rather than back to the ward. Monitor CK, potassium, coagulation (DIC is a late complication) and renal function serially.
Confirm and Flag It Afterwards
Refer for caffeine-halothane contracture testing or genetic testing of RYR1 and CACNA1S, since the diagnosis is inherited and the implications extend to the family. Give the patient written documentation and a medical alert bracelet, counsel first-degree relatives to be tested, and report to the MH registry. Future anesthesia uses a clean machine and a non-triggering technique.
Coagulopathy (INR ≥1.5) + hepatic encephalopathy + no prior liver disease + illness <26 weeks. NAC improves transplant-free survival even in non-acetaminophen ALF. Contact transplant center EARLY. Do NOT correct INR prophylactically.
🔍 Overview
Definition
Acute liver failure (ALF) is defined by the triad: (1) Coagulopathy (INR ≥1.5), (2) Hepatic encephalopathy (any grade), and (3) No prior liver disease, with illness duration <26 weeks. It is a medical emergency with mortality >50% without transplant in many etiologies.
Causes
Acetaminophen (acetaminophen), #1 cause in US/UK. Best prognosis of all causes. Often unintentional (supratherapeutic dosing).
Viral hepatitis, HAV, HBV (most common worldwide), HEV (especially in pregnancy)
Autoimmune hepatitis, can present fulminantly
Wilson disease, suspect in young patients with Coombs-negative hemolytic anemia + ALF
Indeterminate, ~20% remain without identified cause
Classification by Onset
Hyperacute: 0-7 days (acetaminophen, ischemic). Often better prognosis with higher chance of spontaneous recovery.
Acute: 8-28 days
Subacute: 29 days to 26 weeks (worst prognosis, less cerebral edema but more portal hypertension)
🚨 Management
Immediate Management
Give NAC to ALL acute liver failure, not just acetaminophen.Lee, Gastroenterology 2009 showed improved transplant-free survival in non-acetaminophen ALF (Grades I-II HE).
N-acetylcysteine (NAC), IV protocol: 150 mg/kg over 1h, then 50 mg/kg over 4h, then 100 mg/kg over 16h. Continue until INR <1.5 or transplant.
ICU admission, all ALF patients need ICU-level monitoring.
Contact transplant center EARLY, do not wait for deterioration. Transfer may become impossible once cerebral edema develops.
Intubate for Grade III-IV encephalopathy, airway protection. Avoid propofol if hemodynamically unstable.
🔄 Updated Practice: Old teaching: N-acetylcysteine (NAC) only for acetaminophen overdose. Current practice: NAC improves transplant-free survival in ALL causes of acute liver failure, not just acetaminophen (Lee, Gastroenterology 2009). The benefit is greatest in early hepatic encephalopathy (grades I-II). Give NAC to every ALF patient regardless of etiology, there is no reason to withhold it.
Do NOT correct INR prophylactically. INR is your prognostic marker. Only give FFP/PCC if actively bleeding. Correcting INR blinds you to the trajectory and removes your ability to assess for improvement or need for transplant.
King's College Criteria (Transplant Listing)
Acetaminophen ALF
pH <7.3 after resuscitation, OR
All three: INR >6.5 + Creatinine >3.4 mg/dL + Grade III-IV HE
Non-Acetaminophen ALF
INR >6.5 alone, OR
Any 3 of: age <10 or >40, non-A/non-B hepatitis or drug etiology, jaundice >7 days before HE onset, INR >3.5, bilirubin >17.5 mg/dL
Complications Management
Cerebral edema: Elevate HOB to 30°. Mannitol 0.5-1 g/kg IV (if serum osm <320) or hypertonic saline (23.4%) for acute herniation. Avoid hyperthermia. Target Na 145-155 mEq/L with hypertonic saline prophylaxis.
Hypoglycemia: D10 continuous drip. Check glucose q1-2h. Common and life-threatening (failed hepatic gluconeogenesis).
Coagulopathy: Only treat if actively bleeding. Paradoxically balanced hemostasis (low pro- and anti-coagulant factors). Routine FFP is harmful.
Infection: Low threshold for empiric antibiotics. Surveillance cultures daily. Up to 80% develop bacterial infection, 30% fungal.
AKI: Common (50-70%). Avoid nephrotoxins. CRRT preferred over intermittent HD (less hemodynamic instability, better ICP control).
🧪 Workup
Diagnostic Workup, Find the Cause
Etiology-specific workup should be sent simultaneously on arrival:
Acetaminophen level, check even if not suspected (unintentional overdose is common)
Viral serologies: HAV IgM, HBsAg, HBc IgM, HCV RNA (not just anti-HCV), HEV IgM (if pregnant or endemic area)
Check glucose q1-2h. Hepatic gluconeogenesis fails, hypoglycemia is common and dangerous.
Lactulose
Hepatic encephalopathy
30 mL PO/NG q2h titrated to 3-4 BMs/day
Role in ALF is less established than in cirrhotic HE, but often given. Avoid excessive diarrhea (volume depletion).
Piperacillin-tazobactam
Empiric antibiotics
4.5 g IV q6h
Low threshold. Infection in up to 80%. Fungal prophylaxis (fluconazole) may be warranted.
🏥 Rounds
Pimp Questions
❓ Why do we give NAC in non-acetaminophen acute liver failure?
The Lee 2009 study showed that IV NAC improved transplant-free survival in non-acetaminophen ALF, specifically in patients with Grade I-II encephalopathy (52% vs 30% survival). Mechanism likely relates to antioxidant properties and improved hepatic microcirculation.
❓ Why should you NOT correct INR prophylactically in ALF?
INR is your single best prognostic marker in ALF. Giving FFP/PCC masks the trajectory, you cannot tell if the liver is recovering or worsening. Paradoxically, ALF patients have balanced hemostasis (both pro- and anti-coagulant factors are reduced). They are NOT at increased bleeding risk despite high INR. Only give blood products if actively bleeding or before an invasive procedure.
❓ How do you suspect Wilson disease in ALF?
Young patient (<40) + ALF + Coombs-negative hemolytic anemia + very low alkaline phosphatase (AP:bilirubin ratio <4) + AST:ALT ratio >2.2 + low ceruloplasmin. Wilson ALF has a near-100% mortality without transplant, list immediately.
Clinical Examples
📋 Case 1, Acetaminophen-Induced ALF
Patient: 28F presents with 5 days of nausea, vomiting, and jaundice. Reports taking "extra-strength Tylenol" ~4-6 g/day for 10 days for back pain. No prior liver disease.
Key findings: HR 110, BP 95/60, confused with asterixis (Grade II HE). ALT 8,400, AST 10,200, total bilirubin 8.5, INR 4.8, Cr 2.1, pH 7.28, lactate 6.2, acetaminophen level 45 mcg/mL.
Management:
IV NAC immediately (150 mg/kg over 1h, then 50 mg/kg over 4h, then 100 mg/kg over 16h). Continue until INR < 2 and improving
Do NOT correct INR prophylactically -- it is the best prognostic marker. Only give FFP/PCC if actively bleeding
Apply King's College Criteria serially: pH < 7.3 after resuscitation = list for transplant
ICU admission. Monitor glucose q1-2h (hepatic gluconeogenesis fails). For cerebral edema: hypertonic saline, target Na 145-155
Teaching point: Acetaminophen ALF has the best prognosis if treated promptly with NAC. Unintentional supratherapeutic dosing is more common than intentional overdose. Never correct INR prophylactically -- it masks prognosis.
📋 Case 2, Non-Acetaminophen ALF (Autoimmune Hepatitis)
Patient: 35F with no prior history, presents with 2 weeks of fatigue, jaundice, and dark urine. Now confused and unable to follow commands. PMH: Hashimoto thyroiditis.
Key findings: Jaundiced, Grade III HE. ALT 2,100, AST 1,800, total bilirubin 22, INR 3.6, IgG 3,200 (markedly elevated), ANA 1:640, anti-smooth muscle antibody positive. Viral hepatitis serologies negative.
Management:
IV NAC for all non-acetaminophen ALF -- improves transplant-free survival in Grade I-II HE Lee, 2009
Autoimmune hepatitis causing ALF: trial of methylprednisolone 60 mg IV daily. If no improvement in 7 days, proceed to transplant listing
Transjugular liver biopsy to confirm diagnosis and assess for cirrhosis
Early transplant hepatology involvement -- autoimmune ALF has worse prognosis than acetaminophen ALF if steroid-unresponsive
Teaching point: NAC benefits ALL causes of ALF, not just acetaminophen. Autoimmune hepatitis causing ALF can receive a steroid trial, but do not delay transplant evaluation. Elevated IgG + autoantibodies in a young woman = think autoimmune.
📋 Case 3, Wilson Disease Presenting as ALF
Patient: 22M presents with acute jaundice, confusion, and dark urine x 1 week. No medications. Sister diagnosed with Wilson disease at age 18.
Key findings: Kayser-Fleischer rings on slit lamp. AST 1,400, ALT 600 (AST:ALT > 2.2), ALP 45 (paradoxically LOW), total bilirubin 32, INR 5.2. Ceruloplasmin 8 (low). Hgb 7.2 with Coombs-negative hemolytic anemia (reticulocytes 8%, haptoglobin < 10, LDH 890). 24h urine copper 1,200 mcg.
Management:
List for transplant immediately -- Wilson ALF has near-100% mortality without transplant. No medical therapy reverses fulminant Wilson
Revised Wilson Prognostic Index > 11 = transplant indicated
D-penicillamine and trientine are NOT effective in fulminant Wilson disease (too slow)
Supportive: NAC, plasmapheresis or MARS as bridge to transplant to remove copper
Teaching point: Wilson ALF has a classic triad: Coombs-negative hemolytic anemia + very low ALP + AST:ALT > 2.2. The ALP:bilirubin ratio < 4 is highly specific. This is a transplant emergency -- chelation does not work fast enough.
Sample Presentation
Mrs. Patel is a 28-year-old woman presenting with 5 days of nausea, vomiting, and jaundice, now with confusion and asterixis. She reports taking "extra-strength Tylenol" for back pain, approximately 4-6 g/day for the past week. VS: T 37.2, HR 110, BP 95/60, RR 22. Labs: ALT 8,400, AST 10,200, total bilirubin 8.5, INR 4.8, Cr 2.1, acetaminophen level 45 mcg/mL, pH 7.28, lactate 6.2, ammonia 98. Hepatitis serologies pending. NAC drip started immediately. Transplant hepatology notified.
Key Points: ALF from supratherapeutic acetaminophen (unintentional). Meets ALF criteria: INR ≥1.5 + encephalopathy + no prior liver disease. NAC is the priority. Do NOT correct INR unless actively bleeding. Apply King's criteria serially: pH 7.28 (close to 7.3 cutoff), if pH drops below 7.3 after resuscitation, meets criteria for transplant listing. Monitor glucose, ammonia, and neuro status closely. Acetaminophen ALF has the best prognosis of all causes if treated promptly.
Monitoring
INR, LFTs q6-12h, trending INR is your prognostic window. Rising INR despite NAC = worsening. Falling INR = recovery.
Glucose q1-2h, hypoglycemia is life-threatening and common. D10 drip.
Ammonia level q12-24h, levels >150-200 mcmol/L associated with cerebral herniation.
Neuro checks q1-2h, grade encephalopathy (West Haven criteria). Grade III-IV requires intubation.
Lactate q6-12h, rising lactate in acetaminophen ALF is a poor prognostic sign.
BMP q6h, K+, Na+, creatinine, phosphate trending.
Urine output, target >0.5 mL/kg/h. AKI develops in 50-70%.
King's College Criteria, reassess at least daily for transplant listing urgency.
ICP monitoring, controversial. Consider in Grade III-IV HE if transplant candidate. Target CPP >60 mmHg, ICP <20 mmHg.
📋 Summary
Summary
The Definition Is Precise
Coagulopathy with INR 1.5 or above, plus hepatic encephalopathy, in a patient with no prior liver disease and an illness lasting under 26 weeks.Encephalopathy is what separates acute liver failure from severe acute hepatitis, and its appearance is the moment the transplant center should be called.
Call the Transplant Center Early
Before the patient looks like they need it. Deterioration is measured in hours, and cerebral edema and hemodynamic instability make transfer progressively more dangerous. A patient who becomes too unstable to move has lost the option.
Give NAC to Everyone
N-acetylcysteine is no longer just for acetaminophen.It improves transplant-free survival in non-acetaminophen acute liver failure (Lee, Gastroenterology 2009), with the benefit concentrated in grade I to II encephalopathy. Start it while the cause is still being worked up.
Do Not Correct the INR Prophylactically
The INR is the prognostic marker and the transplant listing criterion. Correcting it blinds you to the trajectory and removes the ability to tell improvement from deterioration. Give plasma or PCC only for active bleeding or before an invasive procedure. These patients are not truly auto-anticoagulated: pro- and anticoagulant factors fall together, so the INR overstates the bleeding risk.
Work the Cause Systematically
Acetaminophen is the commonest cause in the United States, including staggered supratherapeutic dosing in a patient who never took an overdose. Also viral hepatitis (A, B, E, HSV), drug-induced liver injury, autoimmune hepatitis, Budd-Chiari, Wilson disease, ischemic hepatitis and pregnancy-related (HELLP, acute fatty liver). Send the acetaminophen level even without a history, plus viral serologies, autoimmune markers, ceruloplasmin in anyone under 40, and a Doppler ultrasound of the hepatic vessels.
Cerebral Edema Is What Kills
It is the leading cause of death and it tracks the grade of encephalopathy and the ammonia level.Head of bed at 30 degrees, minimize stimulation, avoid sedation that clouds the neurologic exam, and intubate at grade III to IV encephalopathy for airway protection. Treat surges with hypertonic saline or mannitol, and use renal replacement therapy to clear ammonia, which also handles the acute kidney injury these patients develop. Lactulose does not have the same role here as in cirrhotic encephalopathy and risks ileus and distension before transplant.
Know the King's College Criteria
Acetaminophen: arterial pH below 7.3 after resuscitation, or the triad of INR above 6.5, creatinine above 3.4 mg/dL and grade III to IV encephalopathy. Non-acetaminophen: INR above 6.5 alone, or any 3 of unfavorable etiology, age under 10 or over 40, jaundice-to-encephalopathy interval over 7 days, INR above 3.5, bilirubin above 17.5 mg/dL. These identify who will die without a transplant, and they are highly specific but insensitive, so failing to meet them is not reassurance.
Manage the Other Organs Deliberately
Check glucose every 1 to 2 h and run a dextrose infusion, because a failing liver stops making glucose and hypoglycemia is common and easily mistaken for worsening encephalopathy. Watch for infection without fever, since these patients are functionally immunosuppressed and sepsis often presents as a deepening encephalopathy. Start stress ulcer prophylaxis, correct electrolytes and phosphate, and avoid nephrotoxins.
Immunosuppression regimens, rejection types, infection timelines, and the critical rule: any transplant patient with rising creatinine is rejection until proven otherwise.
RoundsRx Licensed Content - Unauthorized Use Prohibited🔍 Overview
Prednisone, high dose post-op, taper to 5 mg/day by month 3-6. Some centers do steroid-free protocols.
Types of Rejection
Hyperacute rejection: Minutes to hours. Preformed antibodies against donor ABO/HLA. Immediate graft thrombosis and loss. Prevented by crossmatch testing. Essentially eliminated by modern crossmatching.
Acute cellular rejection (ACR): Weeks to months. T-cell mediated. Most common type. Responds well to pulse steroids (methylprednisolone 500 mg IV x 3 days) or ATG for steroid-resistant cases.
Acute antibody-mediated rejection (AMR): B-cell/antibody mediated. Donor-specific antibodies (DSA). Treat with plasmapheresis + IVIG + rituximab. Harder to treat than ACR.
Chronic rejection: Months to years. Progressive interstitial fibrosis and tubular atrophy (IF/TA). No effective treatment. Leads to slow graft loss.
Month 1-6: Opportunistic infections, CMV (most common), BK virus (nephropathy), PJP (all on prophylaxis during this window)
Month 6+: Community-acquired infections, late CMV (after prophylaxis stopped), BK nephropathy, Listeria, Nocardia
🚨 Management
Rising Creatinine in a Transplant Patient
Any transplant patient with rising creatinine = rejection until proven otherwise. Get tacrolimus level STAT, UA, donor-specific antibodies, and call transplant nephrology. Do NOT just "watch the creatinine."
Acute cellular rejection: Methylprednisolone 500 mg IV daily x 3 days. If steroid-resistant, ATG.
Antibody-mediated rejection: Plasmapheresis (5-7 sessions) + IVIG 100 mg/kg after each session + Rituximab 375 mg/m2. Consider bortezomib (Velcade) for refractory cases.
BK nephropathy: Reduce immunosuppression (lower tacrolimus target, decrease mycophenolate). No specific antiviral. Cidofovir and leflunomide have been tried.
Clinical Example: A 55-year-old man 6 months post-renal transplant presents with Cr rising from 1.4 to 2.3 over 2 weeks. He feels well. Tacrolimus trough 4.2 (subtherapeutic). BK PCR negative. UA bland. DSA panel shows new anti-HLA antibodies. Renal biopsy: C4d positive peritubular capillaritis. Diagnosis: acute antibody-mediated rejection. Initiate plasmapheresis + IVIG + rituximab.
BK PCR monthly x 6 months, then q3 months x 2 years
CMV PCR monthly if D+/R- (highest risk)
💊 Medications
Medications
Drug
Class/Indication
Dose
Notes
Tacrolimus (Prograf)
CNI, maintenance
Varies; target trough 8-12 early, 4-8 late
Nephrotoxic, diabetogenic, tremor, hyperkalemia, hypomagnesemia. Many drug interactions (azoles increase levels, rifampin decreases). Check trough levels.
Mycophenolate (CellCept)
Antiproliferative, maintenance
1000 mg PO BID
GI side effects (diarrhea, nausea). Bone marrow suppression (monitor CBC). Teratogenic. Reduce dose if BK viremia.
Prednisone
Corticosteroid, maintenance
Taper to 5 mg daily
Metabolic effects (hyperglycemia, osteoporosis, weight gain). Some centers do steroid withdrawal.
TMP-SMX (Bactrim)
PJP prophylaxis
1 SS tab daily x 6-12 months
Also provides UTI prophylaxis and Toxoplasma, Nocardia, Listeria coverage.
Valganciclovir (Valcyte)
CMV prophylaxis
900 mg PO daily x 3-6 months
For CMV D+/R- (highest risk) or D+/R+. Monitor CMV PCR. Can cause leukopenia.
Nystatin
Oral candida prophylaxis
5 mL swish and swallow QID x 1-3 months
Prevent oral/esophageal candidiasis while on high-dose immunosuppression.
🏥 Rounds
Pimp Questions
❓ What are the types of rejection and their timelines?
Hyperacute: minutes (preformed antibodies, graft loss). Acute cellular: weeks-months (T-cell mediated, responds to steroids). Acute antibody-mediated: weeks-months (B-cell/DSA, treat with plasmapheresis/IVIG/rituximab). Chronic: months-years (IF/TA, no effective treatment).
❓ What infections occur in each post-transplant time period?
Month 0-1: Surgical site, UTI, donor-derived, early CMV. Month 1-6: CMV (most common), BK virus, PJP, all on prophylaxis. After month 6: Community-acquired, late CMV, BK nephropathy, PTLD.
❓ What is the most important first step when a transplant patient has a rising creatinine?
Check tacrolimus trough level STAT. Supratherapeutic = CNI nephrotoxicity (reduce dose). Subtherapeutic = risk factor for rejection. Then: UA, BK PCR, DSA, renal US. If no clear cause, biopsy. Call transplant nephrology early.
Sample Presentation
Mr. Johnson is a 48-year-old man, 3 months post-deceased donor renal transplant for ESRD from IgA nephropathy. Presenting with creatinine rising from baseline 1.2 to 1.9 over 1 week. No symptoms. Tacrolimus trough: 5.1 (target 6-10, slightly low). BK PCR: negative. CMV PCR: negative. UA: bland. Renal US: no hydronephrosis, normal Doppler flows. DSA: negative. Given rising Cr without clear etiology and subtherapeutic tacrolimus, transplant nephrology recommended renal biopsy. Biopsy showed Banff 1A acute cellular rejection (tubulitis, interstitial inflammation). Started methylprednisolone 500 mg IV x 3 days. Tacrolimus dose increased to target trough 8-10.
Key Points: Rising creatinine in a transplant patient is rejection until proven otherwise. Subtherapeutic tacrolimus was the likely contributing factor. Biopsy is the gold standard. ACR responds well to pulse steroids. Increase maintenance immunosuppression and recheck creatinine in 48-72h.
Monitoring
Tacrolimus trough, check 2-3x/week early, then weekly, then monthly. Target varies by time post-transplant.
BMP weekly initially, creatinine trending, electrolytes (hyperK from tacrolimus, hypoMg)
Lipid panel, dyslipidemia common (tacrolimus, sirolimus)
Cancer screening, skin checks annually (SCC risk 65-250x increased), cervical screening, colon cancer per guidelines. PTLD surveillance (EBV PCR if EBV D+/R-).
📋 Summary
Summary
The Rule That Governs Everything
A rising creatinine in a transplant patient is rejection until proven otherwise. Get a STAT tacrolimus level, urinalysis, renal ultrasound with Dopplers and donor-specific antibodies, and call transplant nephrology.Do not simply watch the creatinine: rejection treated late is graft loss.
The Standard Regimen
Triple therapy: a calcineurin inhibitor (tacrolimus), an antiproliferative (mycophenolate) and a steroid (prednisone tapered to about 5 mg).Tacrolimus troughs run 8 to 12 early and 4 to 8 later. Never stop immunosuppression without transplant input, including through an admission for something unrelated; missed doses cause rejection within days.
Tacrolimus Interactions Are a Daily Hazard
Azole antifungals, macrolides and diltiazem raise the level toward nephrotoxicity; rifampin and antiepileptics drop it toward rejection.Check the level whenever a new drug is started or stopped, and expect tremor, hyperkalemia, hypomagnesemia, hypertension and new-onset diabetes as class effects.
Sort the Differential by Timing
Immediate: hyperacute rejection (preformed antibodies), vascular thrombosis, urinary obstruction. Days to weeks: acute cellular or antibody-mediated rejection, calcineurin inhibitor toxicity, delayed graft function. Months to years: BK virus nephropathy, recurrent primary disease, chronic allograft nephropathy. Prerenal and obstruction are common and reversible, so exclude them first with an ultrasound.
Two Kinds of Rejection, Two Treatments
Acute cellular rejection (T-cell mediated) → pulse methylprednisolone, with anti-thymocyte globulin for steroid-resistant disease. Antibody-mediated rejection → plasmapheresis plus IVIG, sometimes with rituximab. Only a biopsy distinguishes them, which is why the biopsy comes before the treatment whenever the patient can safely wait for it.
The Infection Timeline Is Diagnostic
First month: the usual surgical and nosocomial infections, wound, line, urinary, plus donor-derived. 1 to 6 months, the peak immunosuppression window: CMV, BK virus, PJP, Nocardia, Listeria and reactivated tuberculosis. Beyond 6 months: community-acquired infection, with late CMV and post-transplant lymphoproliferative disease. Knowing where the patient is on that timeline narrows the differential faster than any test.
Prophylaxis Is Not Optional
TMP-SMX single strength daily for 6 to 12 months covers PJP and also Toxoplasma, Nocardia, Listeria and urinary infection. Valganciclovir 900 mg daily for 3 to 6 months in CMV-mismatched recipients (donor positive, recipient negative is the highest risk group), with CMV PCR monitoring; it causes leukopenia, so watch the counts.
Long-Term Risks the Ward Team Forgets
Skin cancer, particularly squamous cell, is dramatically increased and needs annual dermatologic screening and sun protection. Cardiovascular disease is the leading cause of death with a functioning graft, and post-transplant diabetes, hypertension and dyslipidemia are largely drug-induced. Live vaccines are contraindicated, and inactivated vaccines should ideally be given before transplant.
RoundsRx Infographic Series · #177 · Renal & Metabolic · PDF 144 KB
Text version
Nephrology · One Pager
Renal Transplant Medicine
Triple immunosuppression, four rejection types, a predictable infection timeline, and one rule that never bends: a rising creatinine is rejection until proven otherwise.
💊 Immunosuppression: Role and Signature Toxicity
Induction, basiliximab (IL-2 receptor antagonist) for low immunologic risk, or anti-thymocyte globulin (ATG) for high immunologic risk, repeat transplant, and sensitized patients
Tacrolimus (Prograf), the calcineurin inhibitor backbone. Target trough moves with time post-transplant: 8 to 12 ng/mL months 0 to 3, 6 to 10 ng/mL months 3 to 12, 4 to 8 ng/mL after year 1, because rejection risk is highest early and toxicity risk accumulates later. Signature toxicity: nephrotoxic, diabetogenic, tremor, hyperkalemia, hypomagnesemia
Mycophenolate (CellCept) 1000 mg PO BID (or mycophenolic acid 720 mg BID), the antiproliferative. Signature toxicity: GI upset (diarrhea, nausea), bone marrow suppression, teratogenic
Prednisone, high dose post-op then tapered to 5 mg/day by month 3 to 6. Signature toxicity: hyperglycemia, osteoporosis, weight gain. Some centers use steroid-free protocols
Drug interactions matter: azoles increase tacrolimus levels, rifampin decreases them, so any new antimicrobial means rechecking a trough
⚡ Rejection Types and How to Tell Them Apart
Acute cellular rejection (ACR), weeks to months. T-cell mediated, the most common type. Biopsy shows tubulitis and interstitial inflammation (Banff). Responds well to pulse steroids
Acute antibody-mediated rejection (AMR), weeks to months. B-cell and antibody mediated, driven by donor-specific antibodies (DSA). Biopsy shows C4d positive peritubular capillaritis. Harder to treat than ACR
Hyperacute, minutes to hours. Preformed antibodies against donor ABO/HLA cause immediate graft thrombosis and loss. Essentially eliminated by modern crossmatch testing
Chronic rejection, months to years. Progressive interstitial fibrosis and tubular atrophy (IF/TA). No effective treatment, leads to slow graft loss
The distinguishing tests: DSA panel separates AMR from ACR serologically, and transplant biopsy is the gold standard (Banff classification) that settles it
🚨 Rising Creatinine: Step by Step
1
Treat it as rejection until proven otherwise. Do NOT just "watch the creatinine", and call transplant nephrology early
2
Tacrolimus trough STAT: supratherapeutic points to CNI nephrotoxicity (reduce dose), subtherapeutic is a risk factor for rejection. This single number splits the differential
3
Then UA and urine culture (UTI is common post-transplant), BK virus PCR, CMV PCR if symptomatic or in a high-risk window, and DSA if AMR is suspected
4
Renal transplant ultrasound with Doppler to look for hydronephrosis, perinephric collections (lymphocele, hematoma), and vascular stenosis, since obstruction is reversible and must not be missed
5
Biopsy if no clear cause, indicated when creatinine rises >25% from baseline without explanation. It is the gold standard and it decides ACR vs AMR vs BK vs CNI injury
6
Treat by diagnosis: ACR gets methylprednisolone 500 mg IV daily × 3 days (ATG if steroid-resistant). AMR gets plasmapheresis 5 to 7 sessions + IVIG 100 mg/kg after each session + rituximab 375 mg/m² (bortezomib for refractory). BK nephropathy gets immunosuppression reduced, not added
🦠 Infection Timeline
Month 0 to 1: surgical site infections, UTI, donor-derived infections, CMV (especially D+/R-). This window is dominated by the operation itself
Month 1 to 6: opportunistic infections, CMV (most common), BK virus (nephropathy), PJP. This is peak net immunosuppression, which is exactly why everyone is on prophylaxis during this window
Month 6+: community-acquired infections, late CMV once prophylaxis stops, BK nephropathy, Listeria, Nocardia, and PTLD
Prophylaxis: TMP-SMX 1 SS tab daily × 6 to 12 months for PJP, which also covers UTI, Toxoplasma, Nocardia, Listeria
Valganciclovir 900 mg PO daily × 3 to 6 months for CMV D+/R- (highest risk) or D+/R+. Can cause leukopenia
Nystatin 5 mL swish and swallow QID × 1 to 3 months to prevent oral and esophageal candidiasis while immunosuppression is highest
📊 Monitoring
Tacrolimus trough 2 to 3×/week early, then weekly, then monthly, because the target itself changes with time post-transplant
BMP weekly initially: trend creatinine, and watch the tacrolimus electrolyte signature (hyperkalemia, hypomagnesemia)
CBC weekly: leukopenia from mycophenolate and valganciclovir, plus anemia and thrombocytopenia
BK PCR monthly × 6 months, then q3 months × 2 years. >10,000 copies means BK viremia requiring immunosuppression reduction, before it becomes nephropathy
CMV PCR monthly for D+/R- during and after prophylaxis, since late CMV appears once prophylaxis stops
Fasting glucose for post-transplant diabetes (tacrolimus plus steroids), and a lipid panel since dyslipidemia is common on tacrolimus and sirolimus
Cancer screening: annual skin checks (SCC risk increased 65 to 250×), cervical screening, colon cancer per guidelines, EBV PCR for PTLD surveillance if EBV D+/R-
⚠️ Pitfalls
"Watching" a rising creatinine in a transplant patient. Every day of untreated rejection is graft you do not get back
Assuming a normal tacrolimus level excludes a problem. A subtherapeutic trough is itself a rejection risk factor, and a normal level does not exclude AMR
Escalating immunosuppression for BK nephropathy. The treatment is to reduce it (lower tacrolimus target, decrease mycophenolate), since there is no specific antiviral
Forgetting the reversible causes: obstruction, dehydration, NSAIDs, and ACE/ARB all raise creatinine and none need a biopsy
Starting an azole or rifampin without rechecking a trough. Azoles push tacrolimus up into toxicity, rifampin drops it toward rejection
Missing recurrent native disease (FSGS, IgA, diabetic nephropathy) as the cause of graft dysfunction
🏥 Escalate / Call Transplant Nephrology When
Any rise in creatinine, immediately and in parallel with the workup, not after it
Creatinine up >25% from baseline with no clear cause: this is the biopsy threshold
New DSA detected: AMR is on the table and needs plasmapheresis, IVIG, and rituximab, which is not a floor-level decision
ACR that does not respond to pulse steroids: steroid-resistant rejection needs ATG
BK PCR >10,000 copies: immunosuppression reduction has to be balanced against rejection risk by the transplant team
🎓 Carry These Numbers
Tacrolimus targets: 8 to 12 (month 0 to 3), 6 to 10 (month 3 to 12), 4 to 8 (after year 1) ng/mL
ACR: methylprednisolone 500 mg IV daily × 3 days, ATG if steroid-resistant
AMR: plasmapheresis × 5 to 7 + IVIG 100 mg/kg after each session + rituximab 375 mg/m²
BK viremia threshold: >10,000 copies triggers immunosuppression reduction
Biopsy trigger: creatinine >25% above baseline without a clear cause
Compassionate withdrawal of mechanical ventilation when goals of care shift to comfort. NOT euthanasia, removing a treatment that is no longer beneficial. Death may occur minutes to days after extubation. Titrate to comfort, not to death.
🔍 Overview
Overview
Palliative extubation (compassionate extubation, terminal wean) is the planned withdrawal of mechanical ventilation when the goals of care have shifted to comfort-focused measures. This is NOT euthanasia and is NOT physician-assisted death, it is the removal of a life-sustaining treatment that is no longer consistent with the patient's wishes or best interests. It is ethically and legally supported by every major medical society.
Death may occur minutes to days after extubation. Families need to understand this range. Some patients (especially those with intact respiratory drive on minimal settings) may survive for days or even be discharged to hospice.
Indications
Patient/surrogate decision to transition to comfort care
Terminal illness with no further curative options
Goals of care no longer consistent with mechanical ventilation
Advance directive specifying no prolonged mechanical ventilation
Ethical Framework
There is no ethical or legal distinction between withholding and withdrawing treatment
The intent is to relieve suffering, not to hasten death (principle of double effect)
Patient autonomy: competent patients (or surrogates) have the right to refuse any medical treatment
🚨 Management
Pre-Extubation Preparation
Family meeting: Ensure ALL key decision-makers are present (or via phone). Set clear expectations about the process and timeline. Death may occur in minutes or days.
Discontinue monitors and alarms. The family should NOT hear alarms going off. Turn off telemetry, SpO2 monitor, ventilator alarms. Remove unnecessary lines (arterial line, etc.).
Ensure comfort medications are at the bedside BEFORE extubation. Do not start the process until you have drawn up morphine, glycopyrrolate, and midazolam.
Suction the oropharynx gently before extubation to minimize secretions.
Wean ventilator settings: Reduce FiO2 to 21% and PEEP to 0 (or 5). This allows a more gradual transition rather than abrupt cessation.
Pre-medicate: Give morphine 2-4 mg IV 10-15 minutes before extubation to prevent air hunger.
Notify chaplain, social work if family desires.
The Process
Remove restraints (patient should be free)
Disconnect monitors (turn off all alarms)
Suction oropharynx
Reduce vent support gradually OR extubate directly (either approach is acceptable)
Extubate: deflate cuff, remove ETT
Apply oxygen via nasal cannula at 2-4 L (for COMFORT, not saturation monitoring)
Assess comfort immediately, give morphine if any signs of distress
Stay with the family (or have nursing present continuously)
Pronounce when appropriate (no specific time requirement)
Titrate medications to COMFORT, not to respiratory rate or death. The goal is to relieve suffering. If the patient appears distressed (grimacing, accessory muscle use, tachypnea), give more medication. This is NOT hastening death, it is treating dyspnea. The principle of double effect applies: the intent is comfort, even if a foreseeable side effect is respiratory depression.
🧪 Workup
Pre-Extubation Checklist
There is no diagnostic "workup" per se, but a structured checklist is essential:
Goals of care documented?, Written consent from surrogate or documented patient wishes (advance directive).
Ethics consult needed?, If there is disagreement among family members or between team and family.
Legal requirements met?, State-specific requirements for withdrawal of life-sustaining treatment. Two-physician concurrence in some jurisdictions.
DNR/DNAR order written?, Essential before extubation. Prevents Code Blue being called.
Unnecessary interventions discontinued?, Vasopressors, antibiotics, labs, blood draws, nutrition, scheduled medications not contributing to comfort.
Comfort medications ordered and at bedside?, Morphine, glycopyrrolate, lorazepam, haloperidol, scopolamine patch.
Family ready and present?, Ask if they want clergy, specific family members, or rituals before proceeding.
Organ donation discussed?, OPO should be notified per hospital protocol (may have been already).
💊 Medications
Medications
Drug
Indication
Dose
Notes
Morphine
Dyspnea, pain
2-5 mg IV q15min PRN
First-line for air hunger and pain. Titrate to comfort. No ceiling dose for comfort care. Start infusion at 2-5 mg/h if frequent boluses needed. Hydromorphone (Dilaudid) 0.5-1 mg IV is an alternative.
Glycopyrrolate (Robinul)
Secretions ("death rattle")
0.2 mg IV q4h PRN
Anticholinergic, reduces new secretion production. Does NOT clear existing secretions (suction for that). Start early, prevention is easier than treatment.
Lorazepam (Ativan)
Agitation, air hunger, anxiety
1-2 mg IV PRN q2-4h
Adjunct for anxiety and terminal restlessness. Can also help with air hunger refractory to opioids.
Haloperidol (Haldol)
Terminal delirium
0.5-1 mg IV q4-6h PRN
For terminal agitation/delirium not controlled by benzodiazepines. Avoid in QTc prolongation.
Scopolamine patch
Secretions (long-acting)
1-3 patches behind ear q72h
Takes 6-12h to take effect. Apply early if death rattle anticipated. Alternative to glycopyrrolate for sustained effect.
Clinical Example: After extubation, the patient develops tachypnea to 28 and accessory muscle use. The family asks "Is he suffering?" You give morphine 4 mg IV. Within 5 minutes, RR decreases to 18, accessory muscle use resolves, and the patient appears comfortable. This is appropriate symptom management, you treated dyspnea, not the respiratory rate itself.
🏥 Rounds
Pimp Questions
❓ Is there an ethical difference between withholding and withdrawing life-sustaining treatment?
No. Every major medical ethics body (AMA, AACN, SCCM) holds that there is no ethical or legal distinction between withholding and withdrawing treatment. Both are acceptable when the treatment is no longer consistent with the patient's goals. In practice, withdrawing can feel harder emotionally, but the ethical framework is identical.
❓ What is the principle of double effect and how does it apply here?
The principle of double effect states that an action with both a good effect (relieving suffering) and a foreseeable bad effect (potential respiratory depression) is ethically permissible if: (1) the action itself is not inherently wrong, (2) the intent is the good effect, (3) the bad effect is not the means to the good effect, and (4) there is proportionate reason. Giving morphine for dyspnea during extubation is ethical even if it may hasten death, because the intent is comfort.
❓ What medications should be at the bedside BEFORE palliative extubation?
At minimum: Morphine (for dyspnea/pain), glycopyrrolate (for secretions), lorazepam (for agitation/air hunger), and haloperidol (for terminal delirium). These should be drawn up and ready to administer immediately. Do NOT begin extubation without these available.
Sample Presentation
Mrs. Williams is an 82-year-old woman with metastatic pancreatic cancer, intubated 5 days ago for respiratory failure from bilateral pleural effusions and pneumonia. Despite maximum medical therapy, she has not improved. Family meeting held yesterday with oncology, ICU, and palliative care present. Family reports her advance directive states she would not want prolonged mechanical ventilation. Surrogate (daughter) has elected to transition to comfort-focused care. Plan: discontinue vasopressors, antibiotics, and monitoring. Pre-medicate with morphine 4 mg IV. Extubate at family's readiness. Comfort medications at bedside: morphine drip, glycopyrrolate, lorazepam, haloperidol. Chaplain notified. DNR order in place.
Key Points: Clear goals of care discussion documented. Advance directive supports decision. All comfort medications ready at bedside BEFORE extubation. Monitors will be turned off. Family has been counseled that death may occur in minutes to days. Palliative care team is co-managing. This is ethically and legally supported withdrawal of non-beneficial treatment.
Monitoring
Comfort assessment, the ONLY vital sign that matters now. Observe for grimacing, accessory muscle use, restlessness, tachypnea as signs of distress.
Do NOT monitor: SpO2, blood pressure, heart rate on monitors. These are turned off to avoid distressing the family with alarms and numbers.
Secretion assessment: Listen for "death rattle" (gurgling with respirations). Treat with glycopyrrolate or scopolamine. Reassure family this is not choking or suffering.
Medication effectiveness: After each dose, reassess in 10-15 minutes. If still distressed, redose or titrate up.
Bedside nursing, continuous or very frequent (q15-30 min) presence. The patient and family should never be alone during this process.
Time of death: Pronounce when breathing has ceased and no pulse is palpable. There is no specific observation period required (institutional policies vary, typically 2-5 minutes of apnea).
Comfort Monitoring During Extubation
Parameter
Focus
Intervention
Respiratory distress
Tachypnea, accessory muscle use, nasal flaring, air hunger expression
Opioid bolus (morphine 2–5 mg IV or hydromorphone 0.2–0.5 mg IV); titrate infusion upward. Oxygen for comfort only (not SpO₂ targets).
Secretions / death rattle
Noisy/gurgling breathing from pooled oropharyngeal secretions
Pre-emptive opioid before any repositioning/procedure. Continuous infusion rather than relying on PRN.
Family presence
Anyone at bedside; questions; cultural/spiritual needs
Chaplain, social work, bereavement services. Allow family to participate (hand-holding, music). Answer questions honestly.
Time of death
Apnea + absent pulse
Pronounce after 2–5 min of apnea (per institutional policy). Document time. Address family immediately, don't leave.
Do NOT monitor vital signs as outcome measures. The goal of palliative extubation is comfort, not survival or physiologic targets. Remove SpO₂, BP, and HR displays from the room, they distract family and staff from the human process. Focus on the patient's face, breathing pattern, and family presence.
📋 Summary
Summary
What It Is and Is Not
Compassionate withdrawal of mechanical ventilation when the goal of care has become comfort.It is removing a treatment that is no longer benefiting the patient, not euthanasia: the underlying disease causes the death, and the intent is relief of suffering. Say that explicitly to families and to junior staff, because the distinction is what makes the decision bearable and defensible.
Prepare Before You Touch the Tube
Confirm the decision, the decision-maker and the documentation; stop non-comfort medications, monitors, labs, blood draws and vasopressors; discontinue paralytics completely and confirm reversal.A paralyzed patient can be in distress with no way to show it, which is the single most important safety check in the whole protocol.
Pre-Medicate, Do Not Chase
Give opioid and benzodiazepine before extubation, not after distress appears. An opioid infusion with bolus availability, plus a benzodiazepine for anxiety, so the patient is comfortable at the moment the support is removed. Reacting to distress once it has started means the patient has already suffered.
Titrate to Comfort, Not to a Number
Grimacing, accessory muscle use, tachypnea and restlessness are the endpoints.Give more medication when the patient appears distressed.This is not hastening death: the doctrine of double effect applies, and opioids titrated to symptom relief do not shorten survival at appropriate doses.
Turn the Monitors Off
Remove the SpO₂, blood pressure and heart rate displays from the room.They are not outcome measures here, and they pull the family's and the team's attention to a screen instead of to the patient. Keep the focus on the person and on their comfort.
Anticipate the Symptoms Families Find Hardest
Terminal secretions (the death rattle): reposition, stop artificial hydration, and use glycopyrrolate or scopolamine, explaining that it distresses the family rather than the patient. Agonal breathing: irregular gasping is a reflex, not air hunger, and this must be said in advance or it will be interpreted as suffering. Fever, myoclonus and mottling are expected.
Give an Honest Timeframe
Death may follow within minutes or take days.Do not predict a precise interval: families organize themselves around it and are distressed when it passes. Prepare them for the possibility the patient survives extubation, and have a plan for ongoing comfort care on the ward or at home if they do.
Support the Room, Then Document
Allow the family to be present, remove restraints, offer chaplaincy and let them touch and speak to the patient.Debrief the nursing and respiratory staff afterward, since this is one of the heaviest things a team does. Document the goals-of-care discussion, the consent, the medications and the doses, and the comfort assessments, so the record shows a comfort-directed process rather than a bare order.
RoundsRx Infographic Series · #181 · Oncology & Palliative · PDF 138 KB
Text version
PALLIATIVE CARE · One Pager
Palliative Extubation
Withdrawal of a ventilator that no longer serves the patient's goals. Not euthanasia, and not assisted death. Titrate to comfort, never to respiratory rate or to death.
🧪 Indications & Ethical Ground
Indications: patient or surrogate decision to transition to comfort care; terminal illness with no further curative options; goals of care no longer consistent with mechanical ventilation; advance directive specifying no prolonged ventilation.
No ethical or legal distinction between withholding and withdrawing a treatment. Withdrawing feels harder emotionally, but the framework is identical, so discomfort is not a reason to continue.
Principle of double effect: the intent is to relieve suffering; respiratory depression is a foreseeable but unintended side effect, not the means to the goal.
Autonomy: a competent patient or their surrogate may refuse any medical treatment, which is what makes this ethically and legally supported by every major society.
Tell the family the timeline honestly: death may occur minutes to days after extubation. Patients with intact respiratory drive on minimal settings may live for days or even discharge to hospice, and a family expecting minutes will read that as something going wrong.
⚡ Pre-Extubation Checklist
Goals of care documented? Written surrogate consent or a documented advance directive.
DNR/DNAR written? Essential before extubation, otherwise a Code Blue gets called on a planned death.
Comfort medications ordered and physically at the bedside? Morphine, glycopyrrolate, lorazepam, haloperidol, scopolamine patch. Do not start until they are drawn up, because a delay to pharmacy is a patient in air hunger.
Unnecessary interventions stopped? Vasopressors, antibiotics, labs, blood draws, nutrition, and any scheduled medication not contributing to comfort.
Legal requirements met? State-specific rules for withdrawal; two-physician concurrence in some jurisdictions.
Ethics consult needed? Only if there is disagreement within the family or between team and family.
Family ready and present? Ask about clergy, specific family members, or rituals before proceeding.
Organ donation addressed? Notify the OPO per hospital protocol if not already done.
🚨 The Process, Step by Step
1
Family meeting: all key decision-makers present or on the phone, expectations set on process and timeline.
2
Silence the room: turn off telemetry, SpO₂, and ventilator alarms, remove unnecessary lines such as the arterial line, and remove restraints. The family should not hear an alarm during this.
3
Pre-medicate: morphine 2–4 mg IV 10–15 minutes before extubation to prevent air hunger, since treating dyspnea after it starts means the patient suffers through the onset.
4
Suction the oropharynx gently to minimize secretions, then wean FiO₂ to 21% and PEEP to 0 (or 5) for a gradual rather than abrupt transition.
5
Extubate: deflate the cuff, remove the ETT. Gradual vent weaning or direct extubation are both acceptable.
6
Nasal cannula 2–4 L for comfort only, not to chase a saturation number that no longer means anything.
7
Assess comfort immediately, dose for any sign of distress, keep nursing or yourself in the room continuously, and pronounce when appropriate.
💊 Comfort Medications
Morphine2–5 mg IV q15min PRN for dyspnea and pain; infusion 2–5 mg/h if boluses are frequent. First-line for air hunger, no ceiling dose in comfort care. Hydromorphone 0.5–1 mg IV is the alternative
Glycopyrrolate (Robinul)0.2 mg IV/SC q4h PRN for the death rattle. Anticholinergic, it stops new secretions but will not clear what is already pooled, so start early, prevention beats treatment
Lorazepam (Ativan)1–2 mg IV q2–4h PRN for agitation, anxiety, and terminal restlessness; also helps air hunger refractory to opioids
Midazolam1–2 mg IV q1h PRN for restlessness; escalate to continuous infusion if persistent
Haloperidol (Haldol)0.5–1 mg IV q4–6h PRN for terminal delirium not controlled by benzodiazepines. Avoid with QTc prolongation
Scopolamine patch1–3 patches behind the ear q72h for sustained secretion control. Takes 6–12h to work, so apply early if a death rattle is anticipated
📊 What To Monitor
Comfort is the only vital sign now: watch the face and the breathing pattern for grimacing, accessory muscle use, nasal flaring, restlessness, and tachypnea.
Reassess 10–15 minutes after every dose; if still distressed, redose or titrate up.
Secretions: listen for gurgling, treat with glycopyrrolate or scopolamine, reposition, and avoid deep suctioning because it is traumatic. Reassure the family this is not choking or suffering.
Pain: dose pre-emptively before repositioning or any procedure, and prefer a continuous infusion over PRN chasing.
Do NOT display SpO₂, BP, or HR. They are not outcome measures here and the numbers pull family and staff attention away from the patient.
Bedside presence continuous or q15–30 min; the patient and family should never be alone.
Time of death: pronounce after apnea with no palpable pulse, typically 2–5 minutes of apnea per institutional policy. Document the time and stay with the family, do not leave immediately.
⚠️ Pitfalls
Titrating to respiratory rate or to death instead of to comfort. If the patient looks distressed, give more; that is treating dyspnea, not hastening death.
Under-dosing out of fear of the double effect. The intent is comfort, and that intent is what makes the foreseeable respiratory depression ethically acceptable.
Starting before the drugs are at the bedside.
Leaving alarms and monitors on, which turns the family's last hour into a display of numbers.
Extubating without a DNR order in place.
Deep suctioning for the death rattle: traumatic and ineffective against secretions the anticholinergic cannot reach.
Promising a time course. Minutes to days is the honest answer, and some patients survive to hospice discharge.
🏥 Who To Involve
Palliative care co-managing, for symptom titration and family support.
Chaplain and social work before the extubation if the family desires; offer rather than wait to be asked, since afterward is too late for a ritual they wanted.
Ethics when family members disagree with each other or with the team.
Bedside nursing committed to continuous presence for the duration.
The OPO per hospital protocol before withdrawal, because donation options close once the process starts.
Bereavement services for the family afterward, and allow participation during (hand-holding, music).
🎓 The Framing To Use
To the family: "We are removing a treatment that is no longer helping, not causing her death. The illness is doing that."
To yourself and the team: AMA, AACN, and SCCM all hold there is no ethical or legal distinction between withholding and withdrawing treatment.
The four conditions of double effect: the act is not inherently wrong, the intent is the good effect, the bad effect is not the means to the good effect, and there is proportionate reason.
Worked example: post-extubation the patient is tachypneic to 28 with accessory muscle use, the family asks "Is he suffering?" Morphine 4 mg IV, and within 5 minutes the rate is 18 with the accessory use resolved. That is symptom management, you treated the dyspnea, not the number.
Related Topics
Code Status & Advance DirectivesFamily Meeting FrameworkGoals of Care & Symptom ManagementHospice Eligibility CriteriaNon-Opioid Symptom ManagementOpioid Rotation Conversion
Endocrinology / Wards
Inpatient Diabetes Management
Basal-bolus insulin is SUPERIOR to sliding scale alone. Target 140-180 mg/dL in ICU, 100-180 on wards. NEVER hold basal insulin just because a patient is NPO. Sliding scale alone is outdated and reactive, basal-bolus is proactive.
🔍 Overview
Overview
Inpatient hyperglycemia is extremely common and associated with increased mortality, infections, and length of stay. The landmark NICE-SUGAR, 2009 trial showed that targeting 140-180 mg/dL in ICU patients reduces mortality compared to tight glucose control (81-108). For non-ICU patients, the ADA 2026 recommends 100-180 mg/dL. Initiate or intensify insulin for persistent BG ≥180 mg/dL confirmed on two occasions.
ADA 2026 Inpatient Updates:
• Perioperative: A1c goal <8% within 3 months of elective surgery. Target BG 100–180 mg/dL perioperatively. Do NOT postpone surgery based on A1c alone
• CGM in hospital: Hospital-owned CGM devices show feasibility for detecting nocturnal/asymptomatic hypoglycemia (no devices FDA-approved for inpatient use yet)
• Discharge planning: Initiate CGM prior to discharge to facilitate follow-up. Prescribe glucagon at discharge for patients with severe hypoglycemia or impaired awareness
• Cancer treatment hyperglycemia (NEW): Metformin first-line for PI3K/mTOR inhibitor-induced hyperglycemia. Insulin reserved for severe/crisis-level. Close monitoring for immune checkpoint inhibitor patients
Updated Practice: Sliding scale alone is OUTDATED and inferior. RABBIT 2, 2007 showed basal-bolus achieves better glycemic control with LESS hypoglycemia. Sliding scale = reactive (chasing highs). Basal-bolus = proactive (preventing highs).
Glycemic Targets
ICU patients: 140-180 mg/dL (NICE-SUGAR, 2009)
Non-ICU patients: 100-180 mg/dL (pre-meal <140, random <180)
Avoid these on every diabetic admit:
1. Holding basal insulin in an NPO patient, especially T1DM. Basal covers hepatic glucose output (gluconeogenesis), not meals. Holding causes DKA within hours in T1DM, severe hyperglycemia in T2DM. Reduce by 20-50%, never hold.
2. Sliding scale alone for persistent glucoses >180. Reactive (treats highs after they happen) instead of proactive. RABBIT 2, 2007 proved basal-bolus is superior. Convert within 24 h.
3. Continuing SGLT2i on admission for acute illness. Causes euglycemic DKA, glucose may be normal while patient is in DKA. Always hold and check anion gap + beta-hydroxybutyrate if any clinical concern.
4. Not anticipating steroid or tube-feed hyperglycemia. Both are predictable from a known stressor; add the right insulin upfront (NPH for AM prednisone, basal for dex, scheduled coverage for tube feeds) instead of chasing with correction.
5. Discharging on full inpatient insulin doses. Home activity and normal PO intake increase insulin sensitivity. Reduce inpatient TDD by 30-50% at discharge to avoid outpatient hypoglycemia.
Home Diabetes Med Reconciliation, STOP vs CONTINUE
The first decision on every diabetic admit. Most non-insulin agents get held during acute illness; insulin gets adjusted, never stopped entirely.
Class
Drug
Action
Why
Biguanide
Metformin
HOLD if eGFR <30, sepsis, hypoxia, IV contrast within 48 h, AKI, decompensated HF, or hospitalized for serious illness. Restart 48 h post-contrast if Cr stable.
Lactic acidosis risk in tissue hypoxia or impaired clearance. Most inpatients have at least one trigger.
HOLD for surgery / procedural sedation: daily formulations on day of surgery; weekly formulations 1 week before. Continue otherwise unless severe nausea or pancreatitis.
Aspiration risk from delayed gastric emptying (residual food despite NPO >8 h). Multi-society 2023 / ADA 2025-2026 guidance.
Sulfonylurea
Glipizide, Glyburide, Glimepiride
HOLD while inpatient, especially if NPO or variable PO intake.
Long half-life with prolonged hypoglycemia (worst with glyburide + renal impairment). Unpredictable when meals are missed or delayed.
Meglitinide
Repaglinide, Nateglinide
HOLD if NPO or unreliable meal timing.
Mealtime secretagogue, only safe when patient eats predictably.
TZD
Pioglitazone
HOLD if HF exacerbation, edema, or active bladder cancer workup.
Fluid retention worsens HF. Slow onset (weeks) so no inpatient utility either way.
Inpatient carb intake is unpredictable; premixed locks the ratio and risks both hypo and hyperglycemia. Resume premixed at discharge if patient prefers.
SGLT2i euglycemic DKA, the easy-to-miss diagnosis: a patient on empagliflozin admitted for any acute illness can develop DKA with glucose <200. Anion-gap metabolic acidosis + ketones + clinical illness in an SGLT2i user = euglycemic DKA until proven otherwise. Always check anion gap and beta-hydroxybutyrate; do NOT exclude DKA based on a normal glucose alone.
Step 1 -Calculate Total Daily Dose (TDD)
Patient Type
TDD Calculation
Already on insulin at home
Use 80% of home TDD (reduce for illness-related decreased intake)
0.4-0.6 units/kg/day. NEVER hold basal completely.
On steroids
↑ TDD by 20-40% (prednisone causes afternoon/evening hyperglycemia). Increase nutritional insulin at lunch/dinner more than basal.
Step 2 -Split Into Components (50/50)
50% as basal:Glargine (Lantus) or Detemir (Levemir) once daily (usually at bedtime or in the morning). Covers fasting glucose / hepatic glucose output.
50% as bolus (nutritional): Divided into 3 equal doses before each meal, Lispro (Humalog) or Aspart (NovoLog) before meals. Skip if NPO or not eating.
Correction factor:1700 / TDD = how many mg/dL 1 unit of insulin will drop glucose. Add correction to mealtime dose. Example: TDD 32 → 1700/32 ≈ 53 mg/dL per unit.
Sample Correction (Sliding) Scale
Three pre-built ladders by insulin sensitivity. Add correction to the mealtime dose; do NOT use as monotherapy. Pick the ladder by patient phenotype, not by glucose level.
Glucose (mg/dL)
Low-Dose
Medium-Dose
High-Dose
<150
0 U
0 U
0 U
150-199
1 U
2 U
4 U
200-249
2 U
4 U
8 U
250-299
3 U
6 U
10 U
300-349
4 U
8 U
12 U
350-399
5 U
10 U
14 U
>400
6 U + call MD
12 U + call MD
16 U + call MD
Pick low-dose: insulin-naive, <60 kg, eGFR <30, age >75, cirrhosis. Medium-dose: typical T2DM with home TDD 30-60 U. High-dose: home TDD >60 U, on steroids, BMI >35, or known insulin resistance. Why three ladders: a fixed sliding scale that gives 4 U for glucose 200 will overshoot a thin elderly woman and undershoot an obese man on prednisone. Match the dose to the patient's expected response.
Hypoglycemia (< 70)? → reduce the responsible component by 20%. If nocturnal → reduce basal.
NPO? → continue basal (reduce by 20-50% if concerned), hold nutritional, use correction-only sliding scale
Tube feeds? → basal + correction q6h, OR 70/30 insulin BID for continuous feeds
NEVER hold basal insulin just because a patient is NPO. Basal insulin controls hepatic glucose output, not meal glucose. Hold or reduce MEALTIME doses only. Holding basal leads to DKA in type 1 and dangerous hyperglycemia in type 2. If NPO, reduce basal by 20-50% but never hold it entirely.
ICU -Insulin Drip and Drip-to-SubQ Transition
Continuous insulin infusion for critically ill patients (DKA, postoperative, unstable PO intake, persistent BG > 180 despite SubQ).
Transitioning to SubQ -the overlap rule: calculate 24-hr drip total (last 6-8 h average × 24), give 80% of that as daily basal. Give the SubQ basal dose 2-4 hours BEFORE stopping the drip -basal needs time to reach steady-state.
Glargine overlap = 4 hours (slower onset)
Detemir overlap = 2 hours
Why the overlap matters: if you stop the drip before SubQ basal reaches therapeutic level, there's a 2-4 h gap with no effective insulin → rebound hyperglycemia in T2DM, DKA in T1DM.
🔄 Updated Practice: Old teaching (Van den Berghe, 2001): tight glucose control (80-110 mg/dL) in ICU improves mortality. OVERTURNED by NICE-SUGAR, 2009 -intensive insulin INCREASED mortality due to hypoglycemia. Current target: 140-180 mg/dL in ICU. Avoid both hyperglycemia AND hypoglycemia. Sliding-scale-only is also outdated -basal-bolus is superior (RABBIT 2, 2007).
Special Situations
Steroid-Induced Hyperglycemia
The insulin choice depends on the steroid pharmacokinetics. Match the insulin profile to the glycemic-peak pattern, the wrong choice leaves the patient hyperglycemic when the steroid peaks and hypoglycemic when it wears off.
Steroid
Glycemic Pattern
Best Insulin Strategy
Why
Prednisone (once-daily AM)
Afternoon / evening peak (4-8 h after dose), fasting near-normal
NPH 0.1-0.2 U/kg with AM prednisone. Add lispro/aspart correction at lunch and dinner.
NPH peaks at 4-12 h, matches steroid peak. Glargine is the WRONG choice here, flat 24 h profile causes overnight hypoglycemia while under-covering the afternoon peak.
Dexamethasone (long-acting, t½ 36-72 h)
Sustained 24 h hyperglycemia, including fasting
Basal insulin (glargine or degludec) 0.2-0.3 U/kg. Add mealtime lispro/aspart if eating.
Dex effect lasts >24 h so the hyperglycemia is basal-pattern, not just postprandial. NPH would leave a 12 h gap.
IV methylprednisolone (e.g., 60 mg q6h)
Continuous, dose-dependent hyperglycemia throughout the day
Basal-bolus + low-threshold for IV insulin drip if glucose >250 sustained. Start basal at 0.3-0.4 U/kg.
Q6h dosing creates near-continuous steroid effect; need scheduled coverage rather than peak-matched.
Pulse methylprednisolone (1 g IV daily)
Severe hyperglycemia within hours, often glucose >400
IV insulin drip from start. Transition to high-dose basal-bolus once stable.
SubQ insulin can't keep up with the pharmacologic spike; risk of HHS/DKA without aggressive control.
Taper insulin proportionally with the steroid taper. Halve the steroid → halve the steroid-coverage insulin (NPH, or the basal added for dex). Failing to taper is the #1 cause of post-steroid hypoglycemia.
Pre-existing diabetes + new steroids: increase home TDD by 20-40% on day 1, then titrate.
Steroid-induced hyperglycemia in non-diabetics: common, usually resolves with steroid discontinuation. Check A1c on admission to identify undiagnosed pre-existing DM.
Enteral Tube Feeds
The insulin strategy depends on the feeding pattern, not the patient. Match the insulin profile to the carbohydrate delivery profile.
Continuous carbohydrate delivery means continuous insulin need. NPH or 70/30 BID matches the steady-state carb load.
Bolus TF (4-6 boluses/day)
Basal (50% TDD) + rapid-acting (lispro/aspart) before each bolus feed, just like meals. Calculate bolus dose by carb-to-insulin ratio (or as fixed per-bolus amount, e.g., 4-6 U).
Behaves like normal eating; treat each bolus as a meal.
Cyclic TF (e.g., 12 h overnight)
NPH at start of feeds (0.3-0.5 U/kg of feed-period requirement), correction q4-6h during feeds. NO basal during feed-off period.
Hyperglycemia is confined to the feeding window; using long-acting basal causes hypoglycemia during the feed-off hours.
If tube feeds are held unexpectedly (clogged tube, surgery, intolerance) and the patient already received basal insulin or 70/30, start D5W or D10W IV immediately to cover the insulin already on board, otherwise hypoglycemia within 1-4 h. Always include a "hold insulin if feeds held" parameter in the order set, and a D10 standing order for tube-feed holds.
T1DM on tube feeds still needs basal insulin even if NPH is used for the feeding window. NPH alone leaves a 12 h gap, T1DM patients ketose. Add small-dose glargine (typically 30-50% of usual basal).
Transitioning from continuous to bolus feeds (or to oral): recalculate TDD on the new pattern; dropping from continuous to bolus typically reduces TDD by 20-30%.
TPN (Total Parenteral Nutrition)
Start with regular insulin IN the TPN bag at 0.05-0.1 U per gram of dextrose (i.e., 1 U per 10-20 g dextrose). Use the lower end for insulin-naive, higher end for known DM.
Adjust daily based on glucose readings; recalculate when dextrose concentration changes.
Supplement with correction-scale regular insulin SQ q6h for persistent hyperglycemia.
Roll 80% of the prior 24 h correction insulin into the next TPN bag, anticipates rather than chases.
If TPN is held abruptly (line issue, infection workup), the insulin in the bag stops with it, but any SubQ basal already given is still active, hang D10W until the basal effect wears off (8-24 h depending on agent).
Insulin Pump on Admission
Decision: keep the pump on (patient self-manages) or convert to basal-bolus (team manages). The pump is a self-titration device; in critical illness or altered mental status it becomes a hazard.
KEEP pump on if: patient is alert, oriented, hemodynamically stable, eating, and willing/able to self-manage. Most short ward admits.
SWITCH to basal-bolus if: ICU, altered mental status, DKA, surgery >2 h, MRI (pump and CGM are MRI-incompatible), NPO with planned procedures, or patient unable to self-manage.
Conversion to basal-bolus: total daily basal rate from pump (e.g., 0.8 U/h × 24 = 19 U) → give as glargine at the same total dose. Pump bolus ratios → use as mealtime insulin and correction.
Document settings BEFORE disconnection: all basal rates by time-of-day, ICR (insulin-to-carb ratio), correction factor, and target glucose. Restart pump at discharge using the same settings.
MRI: pump and CGM sensors must be removed before scan. Bridge with SubQ glargine + correction during the MRI window; resume pump immediately after.
Hypoglycemia Protocol
Glucose <70 mg/dL: If able to eat, 15 g oral glucose (juice box, glucose tabs). If NPO or unable, D50 25 mL (12.5 g) IV push.
Recheck glucose in 15 minutes. Repeat if still <70.
If recurrent hypoglycemia: reduce insulin dose by 20%, investigate cause (missed meals, renal clearance, adrenal insufficiency).
Clinical Example: A 65-year-old man with T2DM (A1c 9.2, weight 80 kg) is admitted for cellulitis. He was on metformin + glipizide at home. TDD = 0.4 x 80 = 32 units. Basal: glargine 16 units at bedtime. Bolus: lispro 5 units before each meal (~16 units total divided by 3). Correction factor: 1700/32 = ~53, so 1 unit drops glucose by ~53 mg/dL. Hold home metformin and glipizide while inpatient.
Perioperative Diabetes Management
The peri-op window is the highest-risk period for both hypo- and hyperglycemia. Goals: glucose 100-180 mg/dL intra-op and PACU, avoid DKA / euglycemic DKA, prevent aspiration from GLP-1-induced gastroparesis, prevent surgical-site infection from severe hyperglycemia.
A1c Goal Before Elective Surgery (ADA 2026)
Goal A1c <8% within 3 months of elective surgery, when feasible.
Do NOT postpone surgery based on A1c alone, individualize. A1c 8-10 is generally acceptable; >10 warrants discussion with surgical team and endocrine consult if time permits.
BG target 100-180 mg/dL perioperatively. A single elevated finger-stick is not a reason to cancel; sustained >250 with ketones is.
Pre-Operative Med Adjustments
Medication
When to Hold
Why
SGLT2 inhibitor
Hold 3 days before elective surgery (4 days for ertugliflozin)
Euglycemic DKA risk during fasting / surgical stress. FDA label updated 2024.
GLP-1 RA, daily
Hold day of surgery (semaglutide PO, liraglutide, exenatide BID)
Delayed gastric emptying with aspiration risk despite NPO >8 h.
GLP-1 RA, weekly
Hold 1 week before surgery (semaglutide SC, dulaglutide, tirzepatide, exenatide ER)
Long half-life; gastroparesis effect persists for days. ASA 2023 / ADA 2025-2026.
Metformin
Hold morning of surgery; resume 48 h post-op if Cr stable
Lactic acidosis risk with contrast, AKI, or hypoperfusion.
Sulfonylurea / meglitinide
Hold morning of surgery
Hypoglycemia risk while NPO.
Basal insulin (glargine, detemir, degludec)
Give 60-80% of usual dose evening before or morning of surgery
Maintains hepatic glucose suppression. Holding entirely → DKA in T1DM, severe hyperglycemia in T2DM.
NPH
Give 50% of usual morning dose
Has a peak; full dose risks intra-op hypoglycemia under anesthesia.
Mealtime insulin
Hold morning of surgery (NPO)
No food, no need.
Insulin pump
Continue at basal rate only (suspend boluses) if surgery <2 h. For longer surgery → switch to IV insulin drip.
Pump maintains basal coverage, but bolus risks hypoglycemia under anesthesia. Long surgery exceeds reservoir / battery safety margin.
Intra-Op / Post-Op
Intra-op glucose check q1h; q1-2h in PACU until stable.
Resume SubQ insulin once eating: restart basal at 80% of home dose, mealtime insulin at 50% of home (titrate up over 1-2 days).
Resume non-insulin agents: metformin 48 h post-op if Cr stable; SGLT2i once eating regularly and not at AKI risk; GLP-1 once tolerating diet (consider lower starting dose if held >1 week, GI tolerance is reset).
GLP-1 + endoscopy / sedation: retained gastric contents have been seen on EGD up to 72 h after a weekly GLP-1 dose, even with NPO >8 h. If GLP-1 was not held and the procedure proceeds, consider RSI (rapid sequence intubation) or aspiration precautions; some endoscopists will reschedule. Always document GLP-1 hold status pre-procedure.
Discharge Planning, A1c-Driven
The discharge regimen is set by the admission A1c (reflects 3-month average pre-admission glycemia) and the inpatient response. Don't discharge on more insulin than the patient can safely manage at home, and reduce inpatient TDD by 30-50% at discharge because home activity and normal PO intake increase insulin sensitivity.
Admission A1c
Recommended Discharge Regimen
Follow-up
<7%
Resume home regimen (oral agents). If well-controlled on metformin alone, do not add insulin at discharge.
PCP within 2-4 weeks. No urgent endocrine.
7-9%
Resume home oral agents + add basal insulin (glargine 0.1-0.2 U/kg, ~10 U at bedtime) if inpatient glucoses still >180 on orals. Continue metformin if eGFR >30.
PCP within 1-2 weeks for titration. Diabetes educator referral.
>9%
Basal-bolus insulin at discharge. Calculate as 50-70% of inpatient TDD (lower because home insulin sensitivity is higher). Add metformin if not contraindicated.
Endocrinology referral. PCP within 1 week. Diabetes educator MANDATORY.
T1DM (any A1c)
Resume home basal-bolus or pump. Verify insulin supply, glucagon kit, and CGM (if applicable) are in hand at discharge.
Endocrinology within 2 weeks.
Steroid hyperglycemia (no prior DM)
If steroids continuing >2 weeks: discharge on basal insulin OR oral agent based on severity. If steroids tapering quickly: short-term insulin with daily glucose checks.
PCP within 1 week. Reassess once steroids stopped, hyperglycemia often resolves.
Stress hyperglycemia (no DM, no steroids)
Often resolves with illness. Discharge with home glucometer + check fasting BG x 1 week. A1c at PCP visit (not as inpatient, acute illness skews A1c minimally but A1c ≥6.5 inpatient still flags new DM).
PCP within 2-4 weeks. Screen for new-onset DM at follow-up.
ADA 2026 discharge essentials:
• CGM script at discharge for any patient on insulin, especially T1DM, hypoglycemia unawareness, or recent severe hypoglycemia. Improves outpatient adherence and time-in-range, and bridges the gap until first endocrine visit.
• Glucagon prescription for any patient with severe hypoglycemia or impaired awareness during admission. Nasal glucagon (Baqsimi) preferred for caregiver use, no reconstitution needed.
• Diabetes self-management education (DSME) referral for newly insulin-requiring patients: injection technique, glucose monitoring, hypoglycemia recognition, sick-day rules.
• Sick-day rules reviewed before discharge: never stop basal, check glucose q4h when ill, hydration, when to call (BG >300 x 2, ketones, vomiting, can't keep fluids down).
🧪 Workup
Assessment on Admission
A1c, if not checked in past 3 months. Reflects 3-month average. Guides discharge planning.
Home insulin regimen, detailed medication reconciliation. What type, how much, when?
Type 1 vs Type 2, critical distinction. Type 1 patients MUST have basal insulin at all times (DKA risk). Check C-peptide if unclear.
Point-of-care glucose (POC), AC (before meals) and HS (bedtime) = 4x/day for eating patients. Q6h if NPO.
Renal function, CKD increases hypoglycemia risk (reduced insulin clearance). Reduce TDD by 25-50% if eGFR <30.
Nutritional status, is the patient eating? NPO? On TPN? On tube feeds? This drives your insulin strategy.
Once daily. Provides baseline insulin coverage. Do NOT hold when NPO (reduce by 20-50%).
Detemir (Levemir)
Basal (long-acting)
1-2h / 6-8h / 18-24h
May need BID dosing. Slight peak compared to glargine.
Degludec (Tresiba)
Basal (ultra-long-acting)
1h / peakless / >42h
Once daily, very flat profile. Lowest nocturnal hypoglycemia rate of all basal options. Forgiving for missed/late doses (give within 8 h of usual time). Good choice for shift workers and elderly with variable schedules.
Glargine U-300 (Toujeo)
Basal (concentrated, long-acting)
6h / peakless / 24-36h
3x more concentrated than glargine U-100. Smaller injection volume, slower absorption, lower hypoglycemia. Not interchangeable unit-for-unit with U-100 glargine on uptitration.
NPH
Intermediate-acting
1-3h / 4-12h / 12-18h
Key for steroid-induced hyperglycemia (prednisone). Give with morning prednisone, peak matches steroid glycemic peak. Also useful for cyclic tube feeds.
70/30 (NPH 70 / Regular 30)
Premixed (intermediate + short)
30 min / 2-12h / 18-24h
BID dosing matches continuous tube feeds well. Inflexible for variable PO intake, convert to basal-bolus when oral. Common formulations: Humulin 70/30, Novolin 70/30, Humalog Mix 75/25.
U-500 Regular
Concentrated short-acting
30 min / 4-8h / 12-24h
5x more concentrated than U-100 regular. For severe insulin resistance (TDD >200 U/day). Acts more like NPH due to depot volume. Dosing errors are catastrophic, write orders as both units AND mL, and use a dedicated U-500 syringe.
Lispro (Humalog)
Rapid-acting (bolus)
15 min / 1-2h / 3-5h
Give 0-15 min before meals. Hold if NPO. Correction scale uses this.
Aspart (NovoLog)
Rapid-acting (bolus)
15 min / 1-2h / 3-5h
Equivalent to lispro. Interchangeable.
Regular insulin
Short-acting
30-60 min / 2-4h / 6-8h
Used in IV insulin drips (ICU) and added to TPN bags. Give 30 min before meals if used SQ.
D50 (Dextrose 50%)
Hypoglycemia rescue
25 mL (12.5g) IV push
For glucose <70 when patient cannot eat. Recheck in 15 min.
🏥 Rounds
Pimp Questions
❓ Why should you NOT hold basal insulin in NPO patients?
Basal insulin controls hepatic glucose output (gluconeogenesis and glycogenolysis), NOT meal-related glucose. Even when fasting, the liver continuously produces glucose. Without basal insulin, Type 1 patients will develop DKA and Type 2 patients will have dangerous hyperglycemia. The correct approach: reduce basal by 20-50% but never hold it. Hold MEALTIME insulin only.
❓ How do you dose NPH for steroid-induced hyperglycemia?
Give NPH with the morning prednisone dose, NPH has a peak at 4-12h that matches the glycemic peak from prednisone (4-8h after dose). Start at 0.1-0.2 units/kg. Uptitrate daily based on afternoon and evening glucose values. When steroids are tapered, taper NPH proportionally to prevent hypoglycemia.
❓ What is the correction factor formula?
1700 / TDD = correction factor (also called insulin sensitivity factor). This tells you how many mg/dL 1 unit of rapid-acting insulin will lower the blood glucose. Example: TDD 40 units → 1700/40 = 42.5, so 1 unit drops glucose by ~43 mg/dL. For a glucose of 280 with target 150: (280-150)/43 = ~3 units of correction insulin added to mealtime dose.
❓ Why did NICE-SUGAR change ICU glucose targets?
NICE-SUGAR, 2009: 6,104 ICU patients randomized to tight glucose control (81-108 mg/dL) vs conventional (140-180). Tight control increased 90-day mortality (27.5% vs 24.9%) and severe hypoglycemia 13-fold. Likely mechanism: repeated hypoglycemic episodes → adrenergic surges, cardiac arrhythmias, cerebral glucose deprivation. Overturned the prior Van den Berghe 2001 tight-control paradigm. Current ICU target: 140-180 mg/dL.
❓ Why must you overlap basal insulin with the drip when transitioning to SubQ?
Long-acting basal insulin takes several hours to reach therapeutic levels after SubQ injection. Glargine ~4 h to steady state; detemir ~2 h. If you stop the drip and give SubQ basal simultaneously, there's a several-hour gap with no effective insulin → rebound hyperglycemia → DKA risk (especially T1DM, who can ketogenesise within hours of insulin gap). The fix: give SubQ basal 2-4 h BEFORE stopping the drip, write it as an explicit nursing order.
❓ Why is sliding-scale-only insulin especially dangerous in T1DM?
Type 1 diabetics produce ZERO endogenous insulin. Without basal insulin, they develop DKA within 6-12 hours regardless of whether they're eating. Sliding-scale insulin is only correctional (reactive) -treats hyperglycemia after it happens, contains no basal component. A T1DM on sliding-scale-only will: (1) have persistent hyperglycemia (corrected q6h then rises again), (2) develop ketogenesis between checks, (3) progress to DKA within a day. T1DM ALWAYS needs scheduled basal insulin -never hold it completely.
❓ Patient on 40 units of glargine at home is admitted NPO for surgery. What do you do with the insulin?
Give 60-80% of home basal dose (24-32 units glargine). NEVER hold basal insulin entirely in T1DM (DKA risk) or insulin-dependent T2DM (severe hyperglycemia). Hold all mealtime bolus while NPO. Use correction scale q4-6 h PRN. Resume full home basal once eating regularly.
Clinical Examples
📋 Case 1, Initiating Basal-Bolus for Insulin-Naive T2DM
Patient: 70M with T2DM (A1c 9.8), admitted for cellulitis. Home meds: metformin + glipizide. Weight 85 kg. Glucose 280-380 on sliding scale alone × 24h.
Key findings: Sliding scale alone is failing. Patient needs basal-bolus insulin. Home orals (metformin, glipizide) are held inpatient, metformin risk with IV contrast/AKI, glipizide unpredictable when eating is variable.
Management:
Calculate TDD: 0.4 U/kg × 85 kg = 34 U/day (conservative for insulin-naive)
Basal (50%): glargine 17 U at bedtime
Bolus (50% ÷ 3): lispro 5-6 U before each meal (hold if NPO)
Correction factor: 1700/34 = 50 → 1 unit drops glucose ~50 mg/dL. Add correction to mealtime dose
Adjust daily: increase basal by 2-4 U if fasting glucose > 180; increase bolus by 1-2 U if pre-meal values high
Teaching point: The "50/50 split" is the foundation: 50% basal (covers liver glucose output) + 50% bolus (covers meals). Never hold basal in T1DM. Reduce basal by 20-50% in NPO patients but never to zero, the liver never stops making glucose.
📋 Case 2, Steroid-Induced Hyperglycemia
Patient: 65F with no diabetes history, admitted for COPD exacerbation. Started prednisone 40 mg daily. Day 2: glucose pattern, fasting 118, pre-lunch 162, pre-dinner 298, bedtime 264.
Key findings: Classic steroid hyperglycemia pattern: morning glucose near-normal, peaks in afternoon/evening (prednisone peaks at 4-6h → hyperglycemia at 6-12h). Fasting glucose is relatively spared because steroid effect wears off overnight.
Management:
NPH insulin with AM prednisone dose: start 0.15 U/kg = ~10 U (NPH peaks at 6-8h, matching steroid peak)
Correction lispro with lunch and dinner only (where the peaks are)
Do NOT add glargine (flat profile → overnight hypoglycemia while missing afternoon peaks)
Titrate NPH by 2-4 U daily based on pre-dinner and bedtime glucose
When prednisone tapered: reduce NPH proportionally, halve insulin when steroid dose is halved
Teaching point: NPH is the ideal match for once-daily prednisone because its pharmacokinetic profile parallels the hyperglycemic pattern. Glargine is the WRONG choice, its flat 24h profile causes overnight hypoglycemia while under-covering the afternoon peak. Always co-taper insulin with steroids.
📋 Case 3, Transitioning Insulin Drip to SubQ in T1DM
Patient: 25M with T1DM, admitted in DKA (now resolved). Insulin drip at 2.5 U/hr × last 8h. Eating well. BHB 0.3, bicarb 19. Team ready to transition to SubQ.
Key findings: T1DM = zero endogenous insulin. The drip-to-SubQ transition is the highest-risk moment, any gap in insulin coverage → DKA recurrence within hours. The "2-hour overlap" is mandatory.
Management:
Calculate: 2.5 U/hr × 24h = 60 U/day → give 80% = 48 U as daily basal
Give glargine 48 U SubQ NOW, continue drip for 2 more hours (overlap period for SubQ absorption)
After 2h overlap: stop drip. Start mealtime lispro 8 U before each meal + correction scale
Check glucose before each meal + bedtime + 3 AM for first 24h (catch overnight hypo or hyperglycemia)
If patient was on home insulin: use their home regimen if A1c was reasonable (< 8); use drip-calculated dose if home regimen was clearly inadequate
Teaching point: The 2-hour overlap saves lives. Glargine takes ~4h to reach steady state, giving it 2h before stopping the drip ensures no insulin gap. In T1DM, even a 2-hour gap without insulin can trigger ketogenesis. Write the overlap as an explicit nursing order.
Sample Presentation
Mr. Garcia is a 58-year-old man with T2DM (A1c 8.7) admitted for community-acquired pneumonia. He is on prednisone 40 mg daily for severe COPD exacerbation. Home regimen: metformin 1000 mg BID + glipizide 10 mg BID. Weight 90 kg. Admission glucose 280. We transitioned to basal-bolus: TDD 0.4 x 90 = 36 units. Glargine 18 units QHS, lispro 6 units AC meals, correction scale. For steroid-induced hyperglycemia: added NPH 10 units (0.1 u/kg) with morning prednisone. Yesterday's glucoses: AM 145, pre-lunch 168, pre-dinner 242, HS 198. The pre-dinner spike confirms steroid effect, increasing NPH to 14 units. Metformin and glipizide held inpatient.
Key Points: Basal-bolus is superior to sliding scale. Added NPH to match prednisone glycemic peak (afternoon). Adjust NPH daily based on afternoon/evening glucoses. When prednisone is tapered, taper NPH proportionally. Will need discharge diabetes plan based on A1c and response to therapy.
Monitoring
POC glucose AC + HS (before meals and bedtime) = 4 checks/day for eating patients
A1c on admission, guides discharge insulin planning (A1c >9 likely needs insulin at discharge, A1c <8 may resume oral agents).
📋 Summary
Summary
Basal-Bolus, Not Sliding Scale
Sliding scale alone is outdated and inferior. RABBIT 2 showed basal-bolus achieves better control with less hypoglycemia. Sliding scale is reactive, chasing highs after they happen; basal-bolus is proactive, preventing them. Correction-scale insulin is an add-on to a basal-bolus regimen, never the regimen itself.
Targets
140 to 180 mg/dL in the ICU, 100 to 180 mg/dL on the wards.Tight control of 80 to 110 was overturned: NICE-SUGAR showed intensive insulin increased mortality through hypoglycemia. Perioperatively aim 100 to 180 mg/dL, with an A1c goal below 8% within 3 months of elective surgery, but do not postpone surgery on the A1c alone.
Never Hold Basal Insulin Because a Patient Is NPO
Basal insulin covers hepatic glucose output, not meals. Holding it causes DKA within hours in type 1 diabetes and severe hyperglycemia in type 2. Hold or reduce the mealtime doses only, and keep the patient on dextrose-containing fluids while they are not eating.
Build the Regimen in Three Steps
Total daily dose is roughly 0.3 to 0.5 units/kg/day, lower with renal impairment, older age or insulin sensitivity, higher on steroids or with obesity. Split it 50/50: half as basal once daily, half divided across the three meals. Then adjust daily by 10 to 20% based on the pattern, changing one component at a time so you can tell what worked.
Reconcile the Home Medications Deliberately
Stop metformin around contrast, acute kidney injury, hypoperfusion and surgery (lactic acidosis risk). Stop SGLT2 inhibitors on admission for acute illness and 3 to 4 days before surgery.Hold sulfonylureas in the patient who is not eating, since they cause prolonged hypoglycemia. Continue home basal insulin, usually dose-reduced.
Euglycemic DKA Is the Easy Miss
A patient on an SGLT2 inhibitor can be in DKA with a glucose below 200 mg/dL.An anion-gap metabolic acidosis with ketones in an acutely ill SGLT2 inhibitor user is euglycemic DKA until proven otherwise, and the normal glucose is exactly why it gets missed. Treat with insulin plus dextrose, not insulin alone.
ICU Drip and the Transition Off It
Use an insulin infusion for critical illness, persistent hyperglycemia, or after DKA and HHS.The transition is where patients relapse: give the subcutaneous basal dose 2 to 4 h before stopping the drip, because IV insulin has a half-life of minutes and stopping it without overlap leads straight back into ketoacidosis in type 1.
Watch the Steroid Pattern and Plan the Discharge
Morning prednisone produces afternoon and evening hyperglycemia with normal fasting sugars, so weight the correction toward lunch and dinner rather than raising the basal, which just causes overnight hypoglycemia. Discharge regimen is driven by the A1c, and every patient needs teaching, a glucometer, a prescription that is actually affordable, and follow-up within 2 to 4 weeks.
RoundsRx Infographic Series · #87 · Renal & Metabolic · PDF 150 KB
Related Topics
Adrenal CrisisCushing's SyndromeDiabetes InsipidusHypercalcemiaHyperosmolar Hyperglycemic State (HHS)Hyperthyroidism / Graves' Disease
URGENTHeme/Onc
Transfusion Reactions
Recognize, classify, and manage the full spectrum of transfusion reactions. TRALI vs TACO is a board favorite. Stop the transfusion first, ask questions later.
Overview
Transfusion Reaction Types
Type
Timing
Key Features
Treatment
Acute Hemolytic
Minutes
Fever, flank pain, dark urine, hypotension, DIC
STOP transfusion, NS bolus, send blood bank sample
Febrile Non-Hemolytic (FNHTR)
1–6h
Fever, chills, NO hemolysis
Acetaminophen, slow rate. Most common reaction
Allergic (mild)
Min–hours
Urticaria, pruritus, NO hemodynamic instability
Diphenhydramine, can restart slowly
Anaphylactic
Minutes
Hypotension, bronchospasm, angioedema (often IgA deficient)
STOP, IM epinephrine
TRALI
2–6h
Acute hypoxemia, bilateral infiltrates, NO volume overload
Supportive (lung-protective vent), resolves 48–72h. Leading cause of transfusion death
STOP the transfusion for ANY suspected reaction. Send the bag and a new blood sample to blood bank. Clerical error (wrong blood to wrong patient) is the #1 cause of fatal acute hemolytic reactions.
Delayed Transfusion Reactions
Type
Timing
Mechanism
Management
Delayed Hemolytic (DHTR)
3-14 days
Anamnestic antibody response to minor RBC antigens (Kidd, Duffy, Kell)
IgA-deficient patients with anti-IgA antibodies, severe allergic reactions, neonatal transfusions
CMV-negative
From CMV-seronegative donors
Pregnancy, neonates, CMV-negative transplant recipients. Leukoreduction is an acceptable alternative ("CMV-safe")
Volume-reduced
Concentrates product by removing supernatant
Patients at risk for TACO (CHF, renal failure, neonates). Slower infusion rate also helps
AABB Guideline:Carson et al, AABB Clinical Practice Guidelines, JAMA 2016 Use restrictive transfusion threshold (Hgb <7 g/dL) in hemodynamically stable adults. Liberal transfusion (Hgb <10) does not improve outcomes and increases transfusion reaction risk.
Workup
Workup
STOP transfusion, keep IV access
Send blood bank sample: repeat type & screen, DAT, visual hemolysis check
CBC, BMP, LDH, haptoglobin, bilirubin, UA (hemoglobinuria)
Coags if hemolytic/DIC suspected
BNP + CXR for TRALI vs TACO
Blood cultures if febrile (bacterial contamination)
Management
Management by Type
Reaction
Immediate
Ongoing
Acute Hemolytic
STOP, NS bolus
UOP >1 mL/kg/hr, monitor for DIC
FNHTR
Acetaminophen
Can restart slowly. Pre-medicate future
Allergic
Diphenhydramine 25–50mg IV
Restart after urticaria resolves. Washed products for recurrence
Anaphylactic
Epinephrine 0.3–0.5mg IM
IgA level, future: washed/IgA-deficient products
TRALI
O2, intubation PRN
Lung-protective vent, resolves 48–72h. NO diuretics
TACO
Furosemide 20–40mg IV
O2, slow future transfusions (1 mL/kg/hr)
🔄 Updated Practice: Old teaching: premedicate ALL transfusions with acetaminophen + diphenhydramine. Current practice: only premedicate if prior febrile or allergic reaction history. Routine premedication does not prevent serious reactions (TRALI, hemolytic) and delays recognition of early symptoms. Leukoreduction is more effective than premedication at preventing FNHTR.
Medications
Key Medications
Drug
Indication
Dose
Acetaminophen
FNHTR, pre-med
650mg PO/PR
Diphenhydramine
Allergic reactions
25–50mg IV/PO
Epinephrine
Anaphylaxis
0.3–0.5mg IM (1:1000)
Furosemide
TACO
20–40mg IV
Prevention Strategies
Strategy
Prevents
Details
Bedside verification (two-person check)
Acute hemolytic (ABO mismatch)
Verify patient ID, blood type, unit label at bedside. Clerical error is #1 cause of fatal reactions
Leukoreduced products
FNHTR, CMV, HLA alloimmunization
Universal in most blood banks. More effective than premedication King et al, Transfusion 2004
Slow infusion rate
TACO
1 mL/kg/hr (vs standard 2-4 mL/kg/hr) for at-risk patients. Maximum 4h per unit
Washed products
Anaphylaxis (IgA deficiency)
Removes >99% of plasma proteins including IgA
Furosemide 20 mg IV between units
TACO
For patients with CHF, renal failure, or fluid-sensitive states. Give between units, not prophylactically before first unit
Irradiated products
TA-GVHD
25 Gy gamma irradiation. Required for immunocompromised patients
On Rounds
How do you differentiate TRALI from TACO?
TRALI = non-cardiogenic (low BNP, bilateral infiltrates, normal CVP, hypotension, no diuretic response). TACO = cardiogenic (high BNP, JVD, HTN, responds to diuretics). TRALI is the leading cause of transfusion death.
What is the #1 cause of fatal acute hemolytic reactions?
Clerical error, wrong blood to wrong patient (ABO mismatch). Bedside verification is mandatory.
Which patients are at risk for anaphylactic transfusion reactions?
IgA-deficient patients with anti-IgA antibodies. Need washed blood products or IgA-deficient donors.
What labs differentiate TRALI from TACO?
BNP is the key differentiator. TRALI: BNP low/normal (<200 pg/mL), bilateral infiltrates on CXR, hypotension, normal CVP, no response to diuretics. TACO: BNP elevated (>1000 pg/mL), JVD, hypertension, responds to diuretics. Fluid balance also helps - TACO typically has positive fluid balance. Li et al, Transfusion 2014
What is the most common cause of transfusion-related mortality?
TRALI was historically the #1 cause of transfusion-related death. Since 2014-2016 mitigation strategies (predominantly male plasma, avoiding high-titer female donors), TRALI incidence has decreased significantly. Toy et al, Transfusion 2012 TACO is now the most commonly reported cause of transfusion fatalities to the FDA. Acute hemolytic reactions from ABO mismatch remain the most preventable cause of death.
Why are platelets at higher risk for bacterial contamination than RBCs?
Platelets are stored at room temperature (20-24C) on continuous agitation, which promotes bacterial growth. RBCs are stored at 4C, which inhibits most bacterial growth. Bacterial contamination rate: platelets ~1:1000-3000 units vs RBCs ~1:500,000. Most common organisms in platelets: skin flora (Staphylococcus, Streptococcus). In RBCs: cold-growing organisms (Yersinia enterocolitica). This is why platelet units are screened with bacterial detection methods.
When should you restart a transfusion after a reaction?
Only mild allergic reactions (isolated urticaria, no hemodynamic changes) can be restarted after treatment with diphenhydramine and symptom resolution. The rate should be slowed. NEVER restart for: fever/rigors (could be early hemolytic or septic), hypotension, respiratory symptoms, suspected TRALI/TACO, or any hemolytic reaction. When in doubt, do not restart. Send the unit back to blood bank for investigation.
What is the pathophysiology of TRALI?
Two-hit model: (1) First hit: patient's neutrophils are primed by an underlying condition (sepsis, surgery, massive transfusion). (2) Second hit: donor antibodies (anti-HLA or anti-HNA) or bioactive lipids in stored blood activate the primed neutrophils. Activated neutrophils release toxic mediators in the pulmonary vasculature, causing endothelial damage and non-cardiogenic pulmonary edema. This is why using male-only plasma (which lacks anti-HLA from pregnancy) reduces TRALI incidence.
Which transfusion reaction is associated with IgA deficiency?
Anaphylactic transfusion reaction. Patients with selective IgA deficiency (~1:700 prevalence) can develop anti-IgA antibodies. When transfused with IgA-containing plasma, they develop severe anaphylaxis (hypotension, bronchospasm, angioedema) within minutes. Prevention: use washed blood products (removes >99% of plasma IgA) or obtain products from IgA-deficient donors. Check IgA level in patients with unexplained anaphylaxis during transfusion.
Monitoring
Parameter
Frequency
Target
Vital signs
q15min during transfusion
Fever, hypotension, desaturation
SpO2
Continuous
Drop = TRALI/TACO/anaphylaxis
UOP
Hourly if hemolytic
>1 mL/kg/hr
Hemolysis labs
Post-reaction
Hgb, LDH, haptoglobin, DAT
Clinical Examples
📋 Case 1 - TRALI After Plasma Transfusion
Patient: 45M post-op day 2 from exploratory laparotomy for perforated appendix. Receiving FFP for mildly elevated INR (1.8) before drain removal.
Event: 3 hours into second unit of FFP, develops acute dyspnea, SpO2 82% on RA, BP 78/45. Bilateral crackles. No JVD, no peripheral edema.
Assessment: TRALI - acute hypoxemia + bilateral infiltrates + low BNP + no volume overload + within 6h of transfusion. High-risk: recent surgery (neutrophil priming).
Management: STOP transfusion. Supplemental O2, intubated for P/F <150. Lung-protective ventilation (6 mL/kg). NO diuretics (not cardiogenic). Hypotension treated with IVF. Notified blood bank. Improved over 48h, extubated day 3. Donor testing revealed anti-HLA antibodies.
📋 Case 2 - TACO in Elderly CHF Patient
Patient: 82F with CHF (EF 30%) and CKD3, admitted for symptomatic anemia (Hgb 5.8). Ordered for 2 units pRBCs.
Event: Near end of second unit (transfused at standard rate), develops progressive dyspnea, orthopnea. BP 185/95, HR 100, SpO2 88%. JVD present, bilateral crackles and lower extremity edema.
Assessment: TACO - volume overload in CHF patient. Elevated BNP, hypertension, JVD, responds to diuretics.
Management: STOP transfusion. Furosemide 40 mg IV with good diuresis (1.5 L in 4h). O2 via NRB, BiPAP briefly. Symptoms resolved. Future orders: 1 unit at a time, rate 1 mL/kg/hr, furosemide 20 mg IV between units.
📋 Case 3 - Acute Hemolytic Reaction from ABO Mismatch
Patient: 55F with GI bleed receiving pRBC transfusion. Nurse notes blood type on label says "B+" but patient wristband says "A+". 50 mL already infused.
Event: Patient develops acute flank pain, fever to 39.5, dark urine, rigors. BP drops to 80/50. Urine output = dark red.
Labs: DAT strongly positive. Plasma pink (free hemoglobin). LDH 1,200, haptoglobin undetectable, total bili 4.8, Cr rising. UA: hemoglobinuria.
Management: STOP immediately. Aggressive NS resuscitation targeting UOP >1 mL/kg/hr (to prevent renal failure from hemoglobin casts). Serial CBC, coags (watch for DIC), renal function. Blood bank investigation. Incident report. Patient stabilized, Cr peaked at 2.8, returned to baseline by day 5.
Summary
Summary
First Move Is Always the Same
Stop the transfusion for any suspected reaction, then ask questions. Keep the IV open with normal saline, send the bag and a fresh patient sample back to the blood bank, and recheck the identity of patient and unit. Clerical error, the wrong blood to the wrong patient, is the number one cause of fatal acute hemolytic reactions, so the bedside check is where the diagnosis is often made.
Sort by Timing and Vitals
Minutes with fever, flank pain, dark urine and hypotension → acute hemolytic. Minutes with hypotension, bronchospasm and angioedema → anaphylaxis, think IgA deficiency. 1 to 6 h with fever and no hemolysis → febrile non-hemolytic, the most common reaction. Urticaria alone with stable vitals → mild allergic.
TRALI vs TACO
Both give dyspnea and bilateral infiltrates within about 6 hours. TRALI: hypotensive, normal JVP, normal or low BNP, no response to diuretics, treated supportively with lung-protective ventilation and resolving in 48 to 72 h. TACO: hypertensive, raised JVP, elevated BNP, responds to diuresis.Giving furosemide to TRALI does nothing and drops an already low blood pressure further.
The Reaction That Kills Most Often
TRALI is the leading cause of transfusion-related mortality. It is not volume overload and cannot be diuresed out; the management is supportive ventilation, and the prevention is at the donor level (male-predominant plasma).
Which Reactions Let You Restart
Mild allergic urticaria may be restarted slowly after an antihistamine.Everything else stays stopped: hemolytic, anaphylactic, TRALI and TACO reactions all mean that unit is finished.
Do Not Forget the Delayed Ones
Delayed hemolytic at 3 to 14 days from an anamnestic response to minor antigens (Kidd, Duffy, Kell) → supportive, antigen-negative units in future. Transfusion-associated GVHD at 4 to 30 days carries over 90% mortality → prevented with irradiated products in at-risk patients. Post-transfusion purpura at 5 to 12 days → IVIG 1 g/kg for 2 days; platelets usually do not work.
Match the Product Modification to the Risk
Irradiated prevents GVHD in the immunocompromised. Leukoreduced reduces febrile reactions and CMV transmission. Washed removes plasma proteins for IgA deficiency and recurrent severe allergic reactions. Ordering the wrong modifier is not a paperwork issue: the wrong product in an at-risk patient is what causes transfusion-associated GVHD.
Prevention and the Premedication Myth
The best prevention is not transfusing. Use a restrictive threshold of Hgb below 7 g/dL in hemodynamically stable adults; liberal transfusion does not improve outcomes and adds risk. Do not routinely premedicate: acetaminophen and diphenhydramine before every unit does not prevent serious reactions, and should be reserved for patients with a prior febrile or allergic reaction.
Toxidromes guide initial management; specific antidotes save lives. ABCs first, identify the toxidrome, then antidote + supportive care. NEVER intubate a salicylate-toxic patient unless absolutely necessary.
Overview
Acetaminophen
Rumack-Matthew nomogram, APAP level vs time to determine NAC need
AST/ALT may be normal initially (peaks 72–96h). King’s College for transplant referral
Salicylate
Tinnitus, tachypnea (resp alkalosis + AG met acidosis). Alkalinize urine: bicarb drip, target urine pH 7.5–8
Dialysis if level >90 or severe symptoms
NEVER intubate a salicylate-toxic patient unless absolutely necessary. They hyperventilate to compensate for metabolic acidosis. Losing that compensation during intubation → sudden severe acidosis → cardiac arrest.
Sodium bicarbonate 1–2 mEq/kg IV bolus (narrows QRS)
NEVER flumazenil in TCA/benzo co-ingestion (lowers seizure threshold)
🔄 Updated Practice: Old teaching: flumazenil (Romazicon) for all benzodiazepine overdoses. Current practice: AVOID flumazenil in chronic benzo users (precipitates withdrawal seizures) and in mixed overdose with TCAs (removes seizure protection). Flumazenil is only safe for iatrogenic oversedation in benzo-naive patients (e.g., post-procedure). When in doubt, don't give it.
Opioid
Naloxone 0.04–0.4mg IV titrate (start low). Drip for long-acting opioids
BB / CCB
BB:Glucagon 3–5mg IV
CCB:High-dose insulin 1u/kg/hr + D10W
Digoxin
Presentation: nausea/vomiting, visual disturbance (yellow-green halos, "Van Gogh"), confusion, bradyarrhythmia + ectopy (classic: PAT with block, bidirectional VT). Hyperkalemia in acute toxicity (Na/K-ATPase block).
DigiFab (digoxin-specific Fab fragments). Empiric 10–20 vials for acute OD; calculated # vials = (level × weight) / 100.
Atropine 2 mg IV, double q3–5 min until secretions dry (titrate to lung exam, NOT pupils or HR). No upper-limit dose; severe poisonings need 10–100+ mg.
Pralidoxime (2-PAM) 1–2 g IV over 15–30 min, then 500 mg/hr infusion. Reactivates AChE if given before "aging" (12–48h). Best within 6h.
Supportive care first. Pure benzo overdoses rarely cause death; respiratory depression worse with co-ingestion.
Flumazenil (Romazicon) 0.2 mg IV q1 min (max 3 mg). Rarely used.
Avoid flumazenil in: chronic benzo users (precipitates withdrawal seizures), TCA / proconvulsant co-ingestion (removes seizure protection), unknown overdose. Safe only for iatrogenic oversedation in benzo-naive patients.
Local Anesthetic Systemic Toxicity (LAST)
Trigger: inadvertent IV bupivacaine / ropivacaine / lidocaine. Presents with seizures → cardiac arrest (refractory to ACLS).
Intralipid 20% 1.5 mL/kg IV bolus, then 0.25 mL/kg/min infusion. Lipid sink pulls drug out of cardiac tissue. Continue until hemodynamic stability + 10 min.
Avoid vasopressin (worsens outcomes); use low-dose epinephrine (≤ 1 mcg/kg).
Quick Antidote Reference
Poison
Antidote
Dose
Pearl
Acetaminophen
NAC
150 mg/kg/1h → 50 mg/kg/4h → 100 mg/kg/16h
Plot 4h level on Rumack-Matthew. Effective > 24h still.
Salicylate
Sodium bicarbonate + dialysis
Bicarb drip, target urine pH 7.5–8
Dialysis if level > 90 or severe symptoms. Avoid intubation.
Opioid
Naloxone
0.04–0.4 mg IV titrate to RR
Goal is breathing, not consciousness. Drip 2/3 effective bolus/hr for long-acting.
Benzodiazepine
Flumazenil
0.2 mg IV q1 min (max 3 mg)
Rarely used. Avoid in chronic users, TCA co-ingestion.
Presentation: CNS depression / coma (dose-related), hyperammonemic encephalopathy often disproportionate to LFTs, anion gap metabolic acidosis (lactate from mitochondrial dysfunction), hypotension, cerebral edema in severe cases. Delayed: pancreatitis, thrombocytopenia.
L-carnitine 100 mg/kg IV load (max 6 g) over 30 min, then 15 mg/kg q4h. Treats and prevents hyperammonemia and hepatotoxicity (VPA depletes carnitine, shunting metabolism to toxic omega-oxidation pathway).
Hemodialysis if: level > 850 mcg/mL, level > 450 with severe symptoms, refractory shock, cerebral edema, or severe acidosis. VPA is dialyzable once protein binding saturates.
Activated charcoal if < 1–2h post-ingestion and airway protected. Multi-dose charcoal (MDAC) for sustained-release Depakote ER.
Lactulose / rifaximin if hyperammonemic encephalopathy persists despite L-carnitine.
Naloxone is NOT effective. Supportive care for CNS depression: airway, fluids, pressors as needed.
Hyperammonemia pearl: VPA can cause encephalopathy with normal LFTs and a normal VPA level. Always check ammonia in any patient on chronic VPA with altered mental status, even if drug level is therapeutic.
Activated charcoal: Only within 1–2h, alert patient, protected airway. NOT for caustics, hydrocarbons, metals, alcohols.
🔄 Updated Practice: Old teaching: gastric lavage ('stomach pumping') for overdose. Current practice: gastric lavage is rarely performed, risk of aspiration, esophageal perforation, and no proven mortality benefit. Activated charcoal within 1-2 hours of ingestion (alert patient, protected airway) is the only recommended GI decontamination in most cases.
Toxidrome Recognition
Toxidrome
Pupils
HR
Temp
Skin
Mental Status
Examples
Sympathomimetic
Mydriasis
↑↑
↑
Diaphoretic
Agitation, psychosis
Cocaine, amphetamines, MDMA
Anticholinergic
Mydriasis
↑
↑
Dry, flushed
Delirium, hallucinations
Diphenhydramine, TCAs, atropine
Cholinergic
Miosis
↓ or ↑
Normal
Diaphoretic, secretions
Confusion, coma
Organophosphates, nerve agents
Opioid
Miosis (pinpoint)
↓
↓
Normal
CNS depression, coma
Heroin, fentanyl, morphine
Sedative-hypnotic
Normal or miosis
↓
↓
Normal
CNS depression, coma
Benzodiazepines, barbiturates, GHB
Serotonin syndrome
Mydriasis
↑
↑↑
Diaphoretic
Agitation, clonus, hyperreflexia
SSRI + tramadol / MAOI / linezolid; MDMA
Sympathomimetic vs Anticholinergic: Both have mydriasis and tachycardia. The KEY differentiator is skin: sympathomimetics are diaphoretic (wet), anticholinergics are dry (“dry as a bone, red as a beet, hot as a hare, blind as a bat, mad as a hatter”).
Cholinergic Mnemonics:DUMBBBELS, Diarrhea, Urination, Miosis, Bradycardia, Bronchospasm, Bronchorrhea, Emesis, Lacrimation, Salivation. Or SLUDGE, Salivation, Lacrimation, Urination, Defecation, GI distress, Emesis.
GI Decontamination Indications
Method
Indication
Timing
Contraindications
Activated Charcoal
Most oral ingestions of adsorbable substances
Within 1–2 hours (may extend for sustained-release)
Step 1, Osmolar Gap: Calculated Osm = 2(Na) + Glucose/18 + BUN/2.8 + EtOH/4.6. Gap = Measured − Calculated. Gap > 10 suggests toxic alcohol
Step 2, Anion Gap: As toxic alcohols are metabolized, osmolar gap falls and anion gap rises (formic acid from methanol, glycolic/oxalic acid from ethylene glycol)
Key point: A normal osmolar gap does NOT rule out toxic alcohol if presentation is delayed (parent compound already metabolized)
Anaphylactoid Reactions to NAC: Common during first bag (flushing, urticaria, bronchospasm). Slow the rate, give antihistamines. Do NOT withhold NAC, it is lifesaving.
King’s College Criteria (Transplant Referral): pH < 7.3 after resuscitation, OR all three: INR > 6.5, Cr > 3.4, Grade III/IV encephalopathy.
Serotonin Syndrome vs NMS vs Malignant Hyperthermia
Feature
Serotonin Syndrome
Neuroleptic Malignant Syndrome (NMS)
Malignant Hyperthermia (MH)
Onset
Rapid (hours, within 24h)
Slow (days to weeks)
Acute (minutes to hours after anesthetic exposure)
Hours with dantrolene (recheck CK q6h × 36h, may recur)
Mortality
Low (< 1% if recognized)
5–20% (higher if unrecognized)
5–10% with dantrolene (was > 70% before dantrolene)
Genetic
No
No (idiosyncratic)
Yes, autosomal dominant RYR1 mutation, test with caffeine-halothane contracture test
Dantrolene is used in both NMS and MH but the mechanism differs. In MH it directly addresses the RYR1 calcium channel defect. In NMS it reduces muscle rigidity. Cyproheptadine (5-HT2A antagonist) is specific to serotonin syndrome.
Hunter Criteria for Serotonin Syndrome: In the setting of a serotonergic agent, any ONE of: (1) spontaneous clonus, (2) inducible clonus + agitation/diaphoresis, (3) ocular clonus + agitation/diaphoresis, (4) tremor + hyperreflexia, (5) temp > 38°C + ocular or inducible clonus.
MH Early Warning Signs (OR): Unexplained rising EtCO2 is often the FIRST sign. Then tachycardia, jaw rigidity after succinylcholine, generalized rigidity, rapid temperature rise. If suspected: immediately stop triggering agent, switch to IV anesthetics (propofol/opioids), hyperventilate with 100% O2 on clean circuit, give dantrolene, and call MH hotline (1-800-644-9737).
Quick Differentiator: Clonus = Serotonin Syndrome. Lead-pipe rigidity + slow onset = NMS. OR setting + rising EtCO2 + rigidity = MH. All three cause hyperthermia and elevated CK, but the clinical context and neuromuscular exam distinguish them.
↗ See full NMS vs Serotonin Syndrome topic (Neurology) →
Iron poisoning (level > 500 mcg/dL or symptomatic). "Vin rose" urine = active chelation.
Cyproheptadine
12 mg PO load, then 2 mg q2h until improvement (max 32 mg/24h)
Serotonin syndrome (5-HT2A antagonist). Adjunct to benzos and active cooling.
Dantrolene
2–3 mg/kg IV bolus, repeat to 10 mg/kg total
NMS, malignant hyperthermia. Direct skeletal muscle relaxant.
On Rounds
Why is intubating a salicylate patient so dangerous?
They hyperventilate to compensate for metabolic acidosis. During intubation, apnea → CO2 rises → sudden acidemia → salicylate moves into CNS → cardiac arrest. If you must intubate, pre-push bicarb and set vent RR 20–24.
Why is flumazenil contraindicated in TCA overdose?
How do you differentiate sympathomimetic from anticholinergic toxidrome?
Both present with mydriasis, tachycardia, and agitation. The key differentiator is skin: sympathomimetic patients are diaphoretic (wet), while anticholinergic patients are dry (anhidrotic). Anticholinergic also has urinary retention, absent bowel sounds, and flushed skin. Mnemonic: “dry as a bone, red as a beet, hot as a hare, blind as a bat, mad as a hatter.”
A patient presents with elevated osmolar gap but normal anion gap after ingesting an unknown alcohol. What did they drink?
Isopropanol (rubbing alcohol). It is metabolized to acetone (a ketone, not an acid), so it causes an elevated osmolar gap and ketonemia/ketonuria without metabolic acidosis. Methanol and ethylene glycol both cause elevated osmolar gap AND anion gap (as their metabolites are acids: formic acid and glycolic/oxalic acid respectively).
When should you draw an APAP level, and what level mandates NAC?
Draw APAP level at 4 hours post-ingestion (levels before 4h are unreliable). Plot on the Rumack-Matthew nomogram. The treatment line begins at 150 mcg/mL at 4 hours. Any level above the line mandates NAC. If ingestion time is unknown or staggered, start NAC empirically if APAP is detectable (> 10 mcg/mL) or transaminases are elevated.
How do you distinguish serotonin syndrome from NMS at the bedside?
Onset: serotonin syndrome develops within hours; NMS over days to weeks. Neuromuscular: serotonin syndrome has clonus and hyperreflexia; NMS has lead-pipe rigidity and hyporeflexia. CK: mildly elevated in SS vs markedly elevated (> 10,000) in NMS. Treatment: SS responds to cyproheptadine; NMS to dantrolene and bromocriptine.
What are the indications for dialysis in toxic alcohol ingestion?
Dialysis is indicated for methanol or ethylene glycol when: pH < 7.25, renal failure, visual disturbance (methanol), serum level > 50 mg/dL, or deterioration despite fomepizole. Dialysis removes both the parent alcohol and toxic metabolites. Always give fomepizole while awaiting dialysis.
Why do you start naloxone at a low dose (0.04mg) rather than the full 2mg?
In chronic opioid users, high-dose naloxone precipitates acute withdrawal, severe agitation, vomiting (aspiration risk), sympathetic surge (hypertension, tachycardia, pulmonary edema). Goal is to restore respiratory drive, not full consciousness. Start at 0.04–0.4mg IV and titrate to RR > 12. Use a naloxone drip (2/3 of effective bolus/hr) for long-acting opioids.
Clinical Examples
📋 Case 1, Acetaminophen Overdose with NAC Protocol
Patient: 22F presents 6 hours after intentional ingestion of ~30g acetaminophen (60 tablets of 500mg). Nausea, vomiting, RUQ discomfort. VS: HR 92, BP 118/72, afebrile.
Labs: APAP level 220 mcg/mL at 6h post-ingestion, above treatment line on Rumack-Matthew nomogram. AST 45, ALT 38, INR 1.1, Cr 0.9.
Management:
Start NAC immediately: 150 mg/kg IV over 1h → 50 mg/kg over 4h → 100 mg/kg over 16h
Patient develops flushing and urticaria during first bag → anaphylactoid reaction. Slow infusion, diphenhydramine 50mg IV. Do NOT stop NAC
Monitor: APAP level, AST/ALT, INR q6h. At 24h: APAP undetectable, AST peaked at 1,200 then trending down, INR 1.3
Psychiatry consult for intentional ingestion before discharge
Key lesson: NAC is most effective within 8h but still beneficial up to 24–72h. Never withhold NAC for anaphylactoid reactions.
📋 Case 2, Toxic Alcohol Ingestion (Ethylene Glycol)
Patient: 48M found confused with empty antifreeze container. GCS 12. VS: HR 110, BP 100/60, RR 28, SpO2 96%.
Labs: Na 140, K 4.2, Cl 100, HCO3 8, BUN 28, Cr 2.4. AG = 32. Measured Osm 340, calculated 290 → osmolar gap = 50. Lactate 6.2. UA: calcium oxalate crystals. EtOH undetectable.
Clinical reasoning: Elevated osmolar gap + elevated AG + AKI + Ca oxalate crystals = ethylene glycol poisoning.
Management:
Fomepizole 15 mg/kg IV load immediately (blocks alcohol dehydrogenase)
Emergent hemodialysis: pH 7.18, Cr 2.4, multiple indications. Increase fomepizole dosing during HD (q4h)
Thiamine 100mg IV + pyridoxine 50mg IV (shunt metabolism away from toxic metabolites)
IV bicarb drip to correct severe acidosis (target pH > 7.2)
After 2 HD sessions: AG normalized, Cr trending down, osmolar gap closed
Key lesson: Osmolar gap and AG are inversely related over time. Early = high osmolar gap; late = high AG. Normal osmolar gap does NOT exclude toxic alcohol.
📋 Case 3, Serotonin Syndrome
Patient: 35M on sertraline 200mg daily, started tramadol 2 days ago. Presents with agitation, diaphoresis, fever 39.2°C, HR 124, BP 158/92.
Why NOT NMS: Rapid onset (hours not days), clonus (not rigidity), hyperreflexia (not hyporeflexia), diarrhea (not constipation), CK only 680 (not > 10,000).
Management:
Stop all serotonergic agents (sertraline and tramadol)
Cyproheptadine 12mg PO/NG load, then 4mg q4–6h
Benzodiazepines (lorazepam 2mg IV PRN) for agitation and muscle rigidity
Aggressive cooling if temp > 41°C. Antipyretics ineffective (fever from muscle activity)
IV fluids for rhabdomyolysis prevention, monitor CK and renal function
Symptoms improved within 24h. Full resolution by 72 hours
Key lesson: Serotonin syndrome is a clinical diagnosis (Hunter Criteria). Clonus is the hallmark. Rapid onset and rapid resolution once offending agents stopped.
Monitoring by Toxin
Toxin
Key Monitoring
APAP
AST/ALT q6–12h, INR, APAP level, lactate
Salicylate
Serial levels q2h, ABG, urine pH hourly
TCA
Continuous telemetry, serial ECG QRS width
BB/CCB
HR, BP, glucose q15min, K q1h, lactate
Summary
Summary
ABCs, Then the Toxidrome
Airway, breathing, circulation first, then identify the pattern, then give the antidote.Toxidromes are read from pupils, skin, temperature, bowel sounds and mental status: anticholinergic (hot, dry, dilated, delirious), cholinergic (SLUDGE, miosis, bronchorrhea), sympathomimetic (diaphoretic with dilated pupils), opioid (pinpoint pupils, hypoventilation), sedative-hypnotic. Anticholinergic and sympathomimetic differ mainly by whether the skin is dry or wet.
Acetaminophen: Use the Nomogram, Give NAC Early
Draw a level at 4 hours or later and plot it on the Rumack-Matthew nomogram.N-acetylcysteine is nearly fully protective within 8 hours and still worth giving late, including in established hepatic failure. The nomogram does not apply to staggered or chronic ingestion or to unknown timing, where treatment is based on level, transaminases and risk instead.
Never Intubate a Salicylate Patient Unless You Must
They survive by hyperventilating, and the respiratory alkalosis is what keeps the salicylate out of the CNS.Sedation or a ventilator that fails to match their minute ventilation causes an abrupt fall in pH, salicylate redistribution into the brain, and death.Alkalinize with bicarbonate, replace potassium, and dialyze early for severe toxicity, altered mental status or renal failure.
TCA Toxicity Is a Sodium Channel Problem
A QRS above 100 ms predicts seizures and above 160 ms predicts ventricular arrhythmia, and a terminal R wave in aVR is the classic sign.Give sodium bicarbonate to narrow the QRS, which overcomes the sodium channel blockade. Avoid class IA and IC antiarrhythmics and physostigmine, which worsen it.
Give Naloxone to Ventilate, Not to Wake
Titrate to adequate respiration, not to full alertness, because full reversal precipitates withdrawal, agitation and occasionally pulmonary edema. Its half-life is shorter than most opioids, especially methadone and extended-release preparations, so anticipate re-sedation and consider an infusion. Flumazenil is generally avoided: in a chronic benzodiazepine user or a mixed TCA ingestion it precipitates intractable seizures.
Know the High-Dose Rescues
Beta blocker or calcium channel blocker overdose: calcium, glucagon, and high-dose insulin euglycemic therapy, which is the most effective intervention and requires far higher insulin doses than instinct allows, with dextrose and potassium support. Local anesthetic systemic toxicity: intravenous lipid emulsion.Digoxin: digoxin-specific Fab fragments for arrhythmia, hyperkalemia or a large ingestion.
Match the Enhanced Elimination to the Drug
Dialyze for methanol, ethylene glycol, salicylates, lithium, valproate and metformin-associated lactic acidosis.Fomepizole for toxic alcohols, and give it before the confirmatory level returns, since blocking alcohol dehydrogenase prevents formation of the toxic metabolites. Activated charcoal only within about 1 hour, in a protected airway, and it does not bind metals, lithium, alcohols or hydrocarbons.
Treat the Patient, Not the Level
Get a co-ingestion screen including acetaminophen and salicylate in every deliberate overdose, since patients under-report and both are silent early. Check a glucose, an ECG and an anion and osmolar gap on everyone.Call poison control early, and remember that supportive care, airway, glucose, temperature and seizure control, saves more lives than any antidote.
RoundsRx Infographic Series · #34 · Toxicology & Emergencies · PDF 149 KB
Text version
Emergency / Toxicology · One Pager
Toxicology & Overdose
5 toxidromes. APAP + salicylate + ECG on every overdose. Poison Control: 1-800-222-1222. NAC for acetaminophen. Naloxone for opioids. Treat the patient, not the poison.
🔄 Updated Practice: Old teaching: succinylcholine is the default paralytic for RSI due to fastest onset. Current practice: rocuronium (Zemuron) 1.2 mg/kg has equivalent onset (~60 seconds at this dose), is reversible with sugammadex (Bridion), and has fewer contraindications (no hyperkalemia risk in burns/crush/renal failure/neuromuscular disease). Many centers now use rocuronium as the default paralytic for RSI.
Difficult Airway
Bougie (first adjunct), video laryngoscopy, LMA rescue, cricothyrotomy last resort
Failed Airway Algorithm
Step
Intervention
Details
1st attempt fails
Reposition + Bougie
Optimize head position (ear-to-sternal-notch), use bougie as first-line adjunct through direct or video laryngoscopy
2nd attempt fails
Video laryngoscopy
Switch to video if using direct. Different blade (hyperangulated). Limit to 3 total attempts.
Can oxygenate, can't intubate
Supraglottic airway (LMA/iGel)
Place LMA as rescue device. Can ventilate through it and even intubate through certain LMAs.
Can't intubate, can't oxygenate (CICO)
Surgical airway (cricothyrotomy)
Do NOT delay. Scalpel-bougie-tube technique. Vertical skin incision, horizontal through cricothyroid membrane.
The most dangerous decision is the next attempt. After 3 failed laryngoscopy attempts, the probability of success drops and the risk of cannot-intubate-cannot-oxygenate (CICO) rises sharply. Call for help early. Declare a failed airway and move to surgical airway without delay if you cannot oxygenate.
If LEMON assessment is concerning: Have a backup plan BEFORE you push drugs. Consider awake intubation with flexible bronchoscopy, call anesthesia/ENT for support, and always have a surgical airway setup at bedside.
Post-Intubation
Initial Vent Settings
Parameter
Setting
TV
6–8 mL/kg PBW (6 if ARDS)
RR
14–16 (higher if met acidosis)
FiO2
100% → wean to SpO2 92–96%
PEEP
5 cmH2O (higher if ARDS)
CXR for tube position (3–5cm above carina)
Sedation: propofol or midazolam + fentanyl, target RASS -2 to 0
HOB 30–45°, oral care q4h, DVT ppx, stress ulcer ppx
Post-Intubation Sedation & Analgesia
Agent
Dose
Pros
Cons
Best For
Propofol
5–50 mcg/kg/min
Fast on/off, daily awakening trials easy, anti-epileptic
Hypotension, propofol infusion syndrome (PRIS) if > 48h at high doses
Short-term sedation, neuro patients (exam needed)
Dexmedetomidine (Precedex)
0.2–1.5 mcg/kg/h
No respiratory depression, patients are arousable, less delirium
Bradycardia, hypotension, expensive. Not deep enough for some patients.
Accumulation in renal/hepatic failure, worst delirium profile, prolonged sedation
Refractory agitation, seizures. Avoid as first-line.
Fentanyl
25–200 mcg/h
Potent analgesia, hemodynamically neutral
Chest wall rigidity at high doses, accumulation
Analgesia-first strategy, combine with sedative
Analgesia-first approach: Start with fentanyl for pain control, then add sedation as needed to target RASS -2 to 0. Daily sedation awakening trials (SATs) paired with spontaneous breathing trials (SBTs) reduce ventilator days and mortality (ABC Trial, 2008).
Medications
RSI Meds
Drug
Class
Dose
Pearl
Etomidate
Induction
0.3mg/kg
Hemodynamically neutral
Ketamine
Induction
1–2mg/kg
Best for asthma/sepsis
Propofol
Induction
1–2mg/kg
Drops BP. Avoid in shock
Succinylcholine
Depolarizing NMB
1–1.5mg/kg
Fastest (45s). CI in hyperK/burns/NMD
Rocuronium
Non-depolarizing NMB
1.2mg/kg
Reversible with sugammadex 16mg/kg
Induction Agent Comparison, Detailed
Agent
Dose
Onset
Duration
Best Used For
Pros
Cons
Contraindications
Etomidate
0.3 mg/kg IV
15–45s
3–12 min
Default for hemodynamically stable patients. Specifically: head injury / elevated ICP (cerebroprotective), cardiac patients (BP-neutral), borderline hypotension where propofol would crash them. Most commonly used RSI agent in US EDs.
Relative: severe uncontrolled HTN. Old concern about raising ICP is largely debunked.
Propofol
1–2 mg/kg IV
15–30s
5–10 min
Status epilepticus (anti-epileptic) requiring intubation. Stable elective intubation (OR setting). Neurosurgical patients with stable BP (lowers ICP, smooth induction). Patients on chronic opioids / sedatives who tolerate higher doses. Avoid in any hemodynamically unstable patient.
Avoid in hemodynamic instability, shock, hypovolemia, egg/soy allergy (controversial)
Midazolam (Versed) ALTERNATIVE
0.1–0.3 mg/kg IV
2–5 min
30–80 min
When etomidate, ketamine, and propofol are unavailable. Useful in seizing patient requiring intubation (also treats the seizure). Sometimes added in low dose to reduce ketamine emergence reactions.
Anxiolytic, anti-epileptic, amnestic, reversible with flumazenil
Slow onset (2–5 min, too slow for true RSI), variable hypotension, prolonged duration in elderly / liver disease
Avoid in airway compromise from sedative buildup; reverse cautiously in chronic benzo users (precipitates withdrawal seizures).
Paralytic Comparison, Detailed
Feature
Succinylcholine
Rocuronium
Class
Depolarizing NMB
Non-depolarizing NMB
RSI dose
1–1.5 mg/kg IV
1.2 mg/kg IV (RSI dose)
Onset
45 seconds (fastest)
60 seconds at RSI dose
Duration
6–10 minutes (ultra-short)
45–70 minutes
Reversal
None (metabolized by pseudocholinesterase)
Sugammadex (Bridion) 16 mg/kg for immediate reversal
Contraindications
Hyperkalemia, burns > 48h, crush injuries, denervation injuries, NMD, malignant hyperthermia (personal or family hx), prolonged immobility
Ultra-short duration (returns spontaneous breathing faster if you cannot intubate)
Reversible with sugammadex, safer profile, fewer contraindications
Best Used For
Brief / anticipated easy airway when you want fast spontaneous breathing recovery if intubation fails. Useful when sugammadex unavailable. Historically the default but losing ground to rocuronium.
Default in modern practice. Hyperkalemia risk patients (CKD, ESRD, dialysis), burns > 48h, crush / denervation injuries, NMD (Guillain-Barré, ALS, MS, MD), prolonged immobility, MH personal/family history, prolonged paralysis needed (e.g., transport, OR), unknown patient history. Sugammadex availability makes it nearly universal first choice.
Septic shock / hypotension → ketamine (sympathomimetic, maintains BP) + rocuronium (no risk of hyperK in coexisting AKI / renal failure).
Head injury / elevated ICP → etomidate (cerebroprotective, lowers ICP, BP-neutral) + rocuronium (avoids succinylcholine fasciculations that transiently raise ICP).
Status epilepticus → propofol (anti-epileptic, lowers ICP) or midazolam (anti-epileptic, amnestic, reversible with flumazenil) + rocuronium (doesn't mask ongoing seizure activity needing EEG; succinylcholine can trigger MH-like rigidity in some seizure patients).
Hyperkalemia (CKD/ESRD, crush, burns > 48h) → any induction + rocuronium (no K⁺ shift). NEVER succinylcholine (raises K⁺ ~0.5 mEq/L; can be much higher in upregulated extrajunctional receptor states → fatal hyperK arrest).
Stable elective intubation → propofol (smooth induction, fast recovery, anti-emetic) + rocuronium (sugammadex-reversible) or succinylcholine (ultra-short duration if you anticipate quick extubation).
Anticipated difficult airway / awake intubation → ketamine alone (dissociative anesthesia, preserves respiratory drive and airway reflexes). Avoid paralytic until the tube is in and confirmed.
On Rounds
Why is succinylcholine contraindicated in burns/crush injuries?
Extrajunctional ACh receptor upregulation after denervation/injury → massive K+ efflux → fatal hyperkalemia. Risk starts ~48h post-injury. Use rocuronium instead.
When choose ketamine over etomidate?
Ketamine for: asthma (bronchodilator), sepsis/hypotension (sympathomimetic, maintains BP). Increasingly the default ED induction agent.
What are the 7 P's of RSI?
P reparation (equipment, IV, monitors) · P re-oxygenation (3–5 min 100% O2) · P re-treatment (optional: fentanyl, lidocaine) · P aralysis with Induction (push both simultaneously) · P rotection & Positioning (sniffing position, avoid cricoid pressure) · P lacement (laryngoscopy, ETT through cords) · P ost-intubation Management (sedation, vent settings, CXR, ABG)
What does LEMON stand for in difficult airway assessment?
L ook externally (facial trauma, obesity, short neck) · E valuate 3-3-2 rule (3 fingers mouth opening, 3 fingers mentum-hyoid, 2 fingers hyoid-thyroid notch) · M allampati score (III/IV = difficult) · O bstruction/Obesity (angioedema, epiglottitis, BMI > 30) · N eck mobility (C-spine collar, ankylosing spondylitis). If concerning, have backup plan before pushing drugs.
Why is propofol dangerous in a septic shock patient requiring intubation?
Propofol causes vasodilation and myocardial depression, dropping MAP by 20–30% in hemodynamically stable patients. In a septic patient who is already vasodilated with impaired cardiac function, propofol can cause cardiovascular collapse and PEA arrest. Use ketamine instead, it is sympathomimetic, maintains BP, and is increasingly the default induction agent for hemodynamically unstable patients.
What is sugammadex and when do you use it?
Sugammadex (Bridion) is a modified gamma-cyclodextrin that encapsulates and inactivates rocuronium (and vecuronium). Dose for immediate reversal during RSI: 16 mg/kg IV. For routine reversal: 2–4 mg/kg. It provides complete neuromuscular reversal within 2–3 minutes. This is the main advantage of rocuronium over succinylcholine, if you cannot intubate, you can fully reverse paralysis and the patient can resume spontaneous breathing.
What is peri-intubation cardiac arrest and how do you prevent it?
Peri-intubation cardiac arrest occurs in 2–4% of emergency intubations, typically from: (1) Hypoxemia, inadequate pre-oxygenation, (2) Hypotension, induction agents causing vasodilation in already compromised patients, (3) Vagal response, laryngoscopy-induced bradycardia.
Clinical Examples
📋 Case 1, Status Epilepticus Requiring Intubation
Patient: 34-year-old male with epilepsy, brought in with ongoing seizures for 25 minutes. Failed IV lorazepam 4 mg x 2 and levetiracetam loading dose. Still seizing. SpO2 88%, GCS 3.
Decision to intubate: Refractory status epilepticus, failure to protect airway, hypoxemia despite supplemental O2.
RSI approach:
Pre-oxygenate with BVM (patient cannot cooperate due to seizures)
Induction: Propofol 1.5 mg/kg, serves dual purpose as both induction agent AND anti-epileptic. Hemodynamics acceptable (BP 142/88)
Paralytic: Rocuronium 1.2 mg/kg, preferred over succinylcholine because (1) already hyperkalemic risk from prolonged seizures, (2) longer duration is acceptable since patient will need ongoing sedation
Post-intubation: Continue propofol drip for both sedation and seizure suppression. Continuous EEG monitoring.
Teaching point: Propofol is ideal when seizure control is needed alongside intubation. Avoid succinylcholine in status epilepticus due to rhabdomyolysis-induced hyperkalemia risk.
📋 Case 2, Septic Shock with Hemodynamic Caution
Patient: 68-year-old female with pneumonia, septic shock on norepinephrine 15 mcg/min. BP 84/52 despite 3L crystalloid. SpO2 91% on 15L NRB. RR 34, using accessory muscles. GCS 14.
Decision to intubate: Respiratory failure with impending arrest, failing despite maximal oxygen.
RSI approach:
Pre-oxygenate with HFNC at 60L/min (continue during apneic period via nasal cannula at 15L)
Push-dose phenylephrine 100 mcg IV ready at bedside BEFORE induction
Give 500 mL NS bolus during pre-oxygenation
Induction: Ketamine 1.5 mg/kg, sympathomimetic, maintains BP. Do NOT use propofol (will cause cardiovascular collapse)
Paralytic: Rocuronium 1.2 mg/kg
Post-intubation: Immediately increase norepinephrine to compensate for loss of sympathetic drive from sedation. Start fentanyl + propofol at LOW dose for sedation.
Teaching point: The most dangerous part of intubating a septic patient is the hemodynamic collapse that follows induction. Have vasopressors drawn up, fluids running, and choose ketamine. Anticipate BP drop and treat preemptively.
📋 Case 3, Hyperkalemia Patient Avoiding Succinylcholine
Patient: 56-year-old male with ESRD (missed last 2 dialysis sessions), presents with severe dyspnea, bilateral crackles, SpO2 82% on NRB. K+ 7.2. ECG shows peaked T-waves and widened QRS. GCS 15 but tiring rapidly.
Decision to intubate: Severe pulmonary edema with respiratory failure, cannot tolerate BiPAP due to volume overload.
RSI approach:
Pre-intubation: Give calcium gluconate 3g IV for cardiac membrane stabilization, insulin 10 units + D50 for K+ shifting
Pre-oxygenate with BiPAP or HFNC if tolerated
Induction: Etomidate 0.3 mg/kg, hemodynamically neutral (patient is volume overloaded but may drop BP with positive pressure ventilation)
Paralytic: Rocuronium 1.2 mg/kg, NEVER succinylcholine in hyperkalemia (raises K+ by 0.5–1.0 mEq/L → can cause fatal cardiac arrest at K+ 7.2)
Post-intubation: Emergent nephrology consult for dialysis. Low tidal volumes, high PEEP for pulmonary edema.
Teaching point: Succinylcholine is absolutely contraindicated in hyperkalemia. At K+ 7.2 with ECG changes, even a 0.5 mEq/L rise can trigger VFib. Rocuronium is the only paralytic choice. Treat the hyperkalemia before and during intubation.
Monitoring
Parameter
Target
ETCO2
Continuous. 35–45 mmHg. Loss = dislodged tube
SpO2
92–96% (88–92% COPD)
Plateau pressure
<30 cmH2O
ABG
30min post-intubation
CXR
Immediately post-intubation
Summary
Summary
Decide Why You Are Intubating
Four indications: failure to protect the airway, failure to oxygenate, failure to ventilate, and anticipated clinical course. The last is the one residents under-call: the patient who is stable now but predictably will not be in an hour is safer intubated in a controlled setting than crashing at 3 am.
Assess Before You Push Anything
LEMON: Look externally, Evaluate 3-3-2, Mallampati, Obstruction, Neck mobility. If the assessment is concerning, the backup plan must exist before the drugs go in: consider an awake flexible bronchoscopic intubation, call anesthesia or ENT, and have a surgical airway kit open at the bedside.
Preoxygenate Properly
3 to 5 min of 100% oxygen by non-rebreather or high-flow nasal cannula to denitrogenate the functional residual capacity, which is what buys apneic time. Add nasal cannula at 15 L/min underneath for apneic oxygenation, and use the head-up or ramped position, particularly in obesity and pregnancy where FRC is already small.
Rocuronium Has Displaced Succinylcholine as Default
Rocuronium 1.2 mg/kg has an onset equivalent to succinylcholine (about 60 s at that dose), is reversible with sugammadex, and avoids the hyperkalemia, malignant hyperthermia and bradycardia risks. Succinylcholine is contraindicated in hyperkalemia, burns or crush injury more than 48 h old, chronic neuromuscular disease, denervation and a personal or family history of malignant hyperthermia.
Pick the Induction Agent for the Hemodynamics
Asthma or wheeze → ketamine (bronchodilator and sympathomimetic) with rocuronium, which unlike succinylcholine releases no histamine. Septic shock or hypotension → ketamine 1 to 2 mg/kg, or a reduced dose of etomidate. Etomidate 0.3 mg/kg is hemodynamically neutral but causes transient adrenal suppression. Propofol drops blood pressure and is a poor choice in shock.
Confirm With a Waveform, Not With Your Stethoscope
A sustained end-tidal CO₂ waveform is the gold standard. Auscultation alone is not sufficient. No waveform means esophageal until proven otherwise, and cardiac arrest is the one setting where a flat trace can be real, so re-verify by direct visualization.
Three Attempts, Then Declare a Failed Airway
The most dangerous decision is the next attempt. After 3 failed laryngoscopies the success probability falls and the risk of cannot-intubate-cannot-oxygenate climbs sharply. Change something on every attempt (operator, blade, bougie, position), call for help early, and escalate to a supraglottic airway or surgical cricothyrotomy rather than a fourth identical look.
The Period Right After the Tube Is Its Own Danger
Post-intubation hypotension is common: the induction agent removes sympathetic drive and positive pressure drops preload, so anticipate it and have fluids and a vasopressor ready. Confirm placement with a chest x-ray, start lung-protective settings at 6 to 8 mL/kg of predicted body weight, and use an analgesia-first approach, fentanyl before sedative, targeting RASS -2 to 0.
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EMERGENTCardio
ACS Overview
The unifying approach BEFORE you know STEMI vs NSTEMI. ECG within 10 minutes, aspirin 325mg chew, troponin. HEART score for risk stratification. Time is myocardium.
STEMI Equivalents: New LBBB, de Winter T-waves, posterior MI, Wellens syndrome, hyperacute T waves, ST elevation in aVR, high lateral OMI (South African Flag sign), Aslanger pattern. All require emergent reperfusion. See full STEMI Equivalents table →
Treat the underlying cause (e.g., transfuse, treat sepsis, rate control)
Cath indicated?
Yes
Usually no (unless type 1 cannot be excluded)
DAPT needed?
Yes (12 months)
Not routinely, depends on underlying CAD
Clinical Pearl: Type 2 MI is extremely common in hospitalized patients. Troponin elevation in a septic patient with sinus tachycardia is almost always demand ischemia. Reflexively catheterizing these patients causes harm. Fix the underlying problem first.
Killip class at presentation is the single strongest predictor of in-hospital mortality in STEMI. Killip IV = cardiogenic shock → emergent PCI + consider mechanical support (IABP, Impella).
Workup
Workup
12-lead ECG within 10 min. Repeat q15–30min if normal + symptoms persist
Serial troponins (hs-trop 0h, 3h). Right-sided ECG (V4R) for inferior STEMI
Within 24h if stable. Avoid in HF, bradycardia, cocaine
Atorvastatin
80mg immediately (high-intensity)
🔄 Updated Practice: Old teaching: MONA (Morphine, Oxygen, Nitro, Aspirin) as the standard ACS protocol. Current practice: MONA is dead. Morphine may increase mortality in ACS (observational data, use only for refractory pain). Oxygen only if SpO2 <90% (DETO2X-AMI, AVOID trials, hyperoxia may increase infarct size). Focus on: Aspirin + anticoagulation + P2Y12 inhibitor + high-intensity statin + early risk stratification.
Low-risk, no recurrent symptoms, negative stress test
Every minute of delay = more myocardium lost. For every 30-minute delay in reperfusion, 1-year mortality increases by 7.5%. Cath lab activation should occur from EMS when possible (prehospital ECG).
Antiplatelet Strategy
Agent
Loading Dose
Maintenance
Timing / Notes
Aspirin
325 mg chewed
81 mg daily (lifelong)
Give immediately to ALL ACS patients
Ticagrelor
180 mg PO
90 mg BID × 12 mo
Preferred P2Y12. Reversible. Use only with ASA 81mg. PLATO, 2009
Prasugrel
60 mg PO
10 mg daily × 12 mo
STEMI going to PCI. Avoid if prior stroke/TIA, age ≥75, wt <60 kg. TRITON-TIMI 38, 2007
GP IIb/IIIa(antiplatelet -bailout only, bailout = rescue mid-procedure)
Eptifibatide or tirofiban
Infusion during/post PCI
High thrombus burden only. NOT routine before cath. EARLY-ACS, 2009. Why bailout only? Strongest antiplatelet (blocks final common pathway) but biggest bleeding risk -modern P2Y12 + bivalirudin + DES deliver similar ischemic benefit with less bleeding.
Cangrelor
30 mcg/kg IV bolus
4 mcg/kg/min
IV P2Y12 for NPO patients in cath lab. Immediate onset/offset
DAPT Duration: Standard = 12 months. High bleeding risk = 3–6 months. On OAC (AF + stent) = triple therapy × 1 week → OAC + P2Y12 × 12 mo → OAC alone. AUGUSTUS, 2019
<108: Low (<1% death). 109–140: Intermediate. >140: High (>3%) → early invasive <24h
GRACE is preferred per ESC guidelines. TIMI is simpler and widely used in the US. Both guide early invasive vs conservative strategy in NSTEMI.
Post-MI Medications: ABCDE Mnemonic
Letter
Class
Drug / Target
Rationale
A
ACE inhibitor (or ARB)
Lisinopril 2.5–20 mg daily
Prevents remodeling. Start within 24h if stable. EF ≤40%, anterior MI, HF, DM. SAVE, 1992
B
Beta-blocker
Metoprolol succinate or carvedilol
Reduces mortality, prevents arrhythmias. Avoid in cardiogenic shock
C
Cholesterol / Statin
Atorvastatin 80 mg or rosuvastatin 40 mg
High-intensity for ALL post-ACS. Target LDL <70. PROVE IT, 2004
D
Dual antiplatelet
ASA 81 mg + ticagrelor 90 BID
12 months standard. Reduces stent thrombosis and recurrent events
E
Eplerenone (MRA)
Eplerenone 25–50 mg daily
If EF ≤40% + HF symptoms or DM. Monitor K+ and Cr. EPHESUS, 2003
Mnemonic: ABCDE = ACEi, Beta-blocker, Cholesterol (statin), Dual antiplatelet, Eplerenone. Every post-MI patient needs all five unless contraindicated. Add cardiac rehab referral and smoking cessation.
2025 ACS Guideline Changes NEW 2025
2025 ACC/AHA/ACEP/NAEMSP/SCAI Guideline. Replaces the 2013 STEMI and 2014 NSTE-ACS guidelines. Practice-changing updates ordered by bedside impact. Tags below show what changed vs the prior guideline. Biggest behavior changes: shorter DAPT with ticagrelor monotherapy, and short-course triple therapy in AFib + PCI.
Topic
Old practice
2025 update
Why / trial basis
DAPT after PCICHANGED
12 mo DAPT (ASA + P2Y12) for everyone
1 mo DAPT, then ticagrelor monotherapy (Class 1, LOE A). 12 mo still default if not at high bleeding risk.
Aspirin withdrawal at 1 mo with continued ticagrelor cuts BARC 2/3/5 bleeding ~44% with no increase in ischemic events. Benefit largest in NSTE-ACS. TWILIGHT, 2019TICO, 2020T-PASS, 2023
P2Y12 choice
Clopidogrel acceptable
Ticagrelor or prasugrel preferred over clopidogrel post-PCI
More potent platelet inhibition reduces CV death/MI/stroke. Reserve clopidogrel for high bleeding risk or when ticagrelor/prasugrel are contraindicated. PLATO, 2009
AFib + PCI triple therapyCHANGED
Triple therapy (OAC + ASA + P2Y12) for variable durations
Short triple (1 to 4 weeks), then drop ASA, then OAC + clopidogrel through month 12, then OAC alone (Class 1)
Adding ASA to OAC + P2Y12 increases bleeding 3 to 4 fold without reducing ischemic events. Clopidogrel preferred over ticagrelor/prasugrel as the dual partner (bleeding). DOACs (especially apixaban) preferred over warfarin. AUGUSTUS, 2019PIONEER AF-PCI, 2016
LDL target post-ACSCHANGED
Add non-statin if LDL ≥ 70 on max statin
Non-statin if LDL ≥ 70 (Class 1). Reasonable to intensify if LDL 55 to <70 on max statin (Class 2a, lower threshold)
Post-ACS is the highest-risk window. Adding ezetimibe or PCSK9 inhibitor reduces CV events. The 2025 guideline pushes the intensification floor lower than the 2018 cholesterol guideline. FOURIER, 2017ODYSSEY OUTCOMES, 2018
Intravascular imagingUPGRADED
IVUS/OCT Class 2a (2021 revasc guideline)
Class 1 for PCI guidance, especially complex lesions (left main, long lesions, bifurcation, CTO)
Lower cardiac death and stent thrombosis vs angiography alone. RENOVATE-COMPLEX-PCI, 2023ILUMIEN IV, 2023
Multivessel diseaseCHANGED
Culprit-only PCI was the conservative default
Complete revascularization (Class 1). Treat severely stenotic non-culprit lesions same setting or staged.
Reduces recurrent MI and CV death vs culprit-only. COMPLETE, 2019MULTISTARS-AMI, 2023FULL REVASC, 2024
Cardiogenic shockNEW
No proven mechanical support; routine pump use unsupported
Microaxial flow pump (Impella CP) reasonable in select AMI shock (Class 2a). Transfer to shock center (Class 1).
First positive shock RCT to show mortality benefit. Patient selection critical (anterior STEMI, no severe RV failure). Caveats: more bleeding, limb ischemia, AKI. DanGer Shock, 2024
Vascular access
Femoral default
Radial preferred over femoral for PCI in ACS (Class 1)
Reduces bleeding, vascular complications, and mortality. MATRIX, 2015RIVAL, 2011
hs-Troponin protocols
Serial 3 to 6 hr troponins standard
0/1h or 0/2h hs-cTn algorithms formalized for rule-in/rule-out
Faster ED disposition without missed MIs. ESC 2020 already endorsed; 2025 ACC/AHA brings US guidance in line.
Periprocedural anticoagUNCHANGED
UFH for NSTE-ACS; UFH or bivalirudin for STEMI PCI
Same: UFHClass 1 for NSTE-ACS; bivalirudinClass 2a alternative for STEMI PCI, Class 2b for NSTE-ACS
UFH remains the workhorse. Bivalirudin reduces bleeding but did not unseat UFH in trials (BRIGHT-4 was the closest positive signal). Fondaparinux alone does NOT cover PCI (catheter thrombosis risk), add UFH bolus at cath.
📖 What "Class 1" and "LOE A" mean (click to expand)
ACC/AHA guidelines grade every recommendation on two axes: Class of Recommendation (strength) and Level of Evidence (quality of data). The two are written together, e.g., "Class 1, LOE A."
Class
Strength
Phrase you'll see
Bedside translation
Class 1
Strong (Benefit >>> Risk)
"is recommended", "should", "is indicated"
Standard of care. Skipping it without a documented reason is below the standard.
Class 2a
Moderate (Benefit >> Risk)
"is reasonable", "can be useful"
Lean toward doing it. Most experts would.
Class 2b
Weak (Benefit ≥ Risk)
"may be reasonable", "may be considered"
Optional, case-by-case.
Class 3: No Benefit
Moderate against
"is not recommended"
Don't do it, no upside.
Class 3: Harm
Strong against
"potentially harmful", "should not"
Don't do it, actively harmful.
Level of Evidence
Source
LOE A
Multiple high-quality RCTs or meta-analyses. Best evidence.
LOE B-R
One or more moderate-quality Randomized trials.
LOE B-NR
Well-designed Non-Randomized studies.
LOE C-LD
Limited Data: small studies, registries, retrospective.
LOE C-EO
Expert Opinion only, no real evidence.
Trap to avoid: Class 1 with LOE C is still a strong recommendation. The committee believes it strongly even without trial data (e.g., "perform CPR in cardiac arrest" is Class 1 LOE C-EO, no RCT will ever exist). Don't dismiss a Class 1 because the LOE looks weak.
AFib + ACS + PCI bedside recipe (the most common practice change):
Triple therapy (DOAC + ASA + clopidogrel): 1 to 4 weeks. Typically 1 week if low ischemic risk, up to 1 month if high (left main, complex multivessel, recent stent thrombosis).
Dual therapy (DOAC + clopidogrel): through month 12 post-PCI. Aspirin is dropped.
Monotherapy (DOAC alone): after 12 months. Why: the stent has fully endothelialized and chronic dual antithrombotic adds bleeding without ischemic benefit.
P2Y12 choice:clopidogrel preferred (not ticagrelor or prasugrel) once on dual therapy. Why: bleeding risk on top of OAC is unacceptable with potent P2Y12 inhibitors.
OAC choice:DOAC preferred over warfarin unless mechanical valve or severe MS. Apixaban has the most direct ACS+PCI evidence (AUGUSTUS).
What did NOT change. Aspirin 325 mg loading dose, high-intensity statin on day 1, beta-blocker within 24 h if stable, ACEi/ARB if EF ≤ 40% or anterior MI, MRA if EF ≤ 40% with HF or DM, 12 mo DAPT default in patients without high bleeding risk, GRACE/TIMI for NSTEMI risk stratification, door-to-balloon < 90 min, fibrinolysis door-to-needle < 30 min if PCI unavailable. The ABCDE post-MI bundle is intact.
Medications
Key Meds
Drug
Dose
Notes
Aspirin
325mg chew, then 81mg daily
ALL ACS unless true allergy
Ticagrelor
180mg load, 90mg BID
Preferred P2Y12 (PLATO trial). Use aspirin 81mg only
Clopidogrel
600mg load, 75mg daily
Alternative. CYP2C19 polymorphisms
Heparin
60u/kg, 12u/kg/hr
aPTT 1.5–2.5× control
On Rounds
Why avoid nitroglycerin in RV infarct?
RV is preload-dependent. NTG causes venodilation → drops preload → profound hypotension. Give IVF instead. Check V4R before nitrates in inferior STEMI.
STEMI vs NSTEMI vs UA?
STEMI: Complete occlusion, ST elevation, troponin up. Emergent PCI. NSTEMI: Partial occlusion, no ST elevation, troponin elevated. UA: Same mechanism but troponin normal.
What are the door-to-balloon time targets for STEMI?
<90 minutes at a PCI-capable center. <120 minutes if transfer is needed. If PCI cannot be achieved in time, give fibrinolytics within 30 minutes (door-to-needle). Every 30-minute delay increases 1-year mortality by ~7.5%.
What is a Type 2 MI and how does management differ from Type 1?
Type 2 MI = supply-demand mismatch WITHOUT plaque rupture (e.g., tachycardia, anemia, sepsis, hypotension). Treatment = fix the underlying cause (transfuse, treat sepsis, rate control). Do NOT reflexively cath these patients. Type 1 = plaque rupture/erosion → thrombotic occlusion → antiplatelet + anticoag + PCI.
Name the post-MI discharge medications using the ABCDE mnemonic.
A = ACE inhibitor (especially if EF ≤40%). B = Beta-blocker. C = Cholesterol/statin (high-intensity). D = Dual antiplatelet therapy (ASA + P2Y12 × 12 months). E = Eplerenone (if EF ≤40% + HF or DM, per EPHESUS).
What is the Killip classification and why does it matter?
Killip classifies heart failure severity in acute MI. I: No HF (~6% mortality). II: Rales, S3, JVD (~17%). III: Pulmonary edema (~38%). IV: Cardiogenic shock (~67%). Killip class at presentation is the strongest predictor of in-hospital mortality in STEMI.
Why is ticagrelor preferred over clopidogrel in ACS?
The PLATO trial showed ticagrelor reduced CV death, MI, and stroke compared to clopidogrel. Ticagrelor is a reversible, direct-acting P2Y12 inhibitor (no hepatic activation needed), so it is not affected by CYP2C19 polymorphisms that render clopidogrel ineffective in ~30% of patients. Trade-off: more dyspnea and bleeding.
Name four STEMI equivalents that require emergent cath lab activation.
1) New LBBB + ischemic symptoms. 2) De Winter T-waves (upsloping ST depression + tall T-waves in precordial leads = proximal LAD occlusion). 3) Posterior MI (ST depression V1–V3 + tall R waves; confirm with V7–V9). 4) Wellens syndrome (biphasic/deeply inverted T-waves V2–V3 = critical LAD stenosis). All require emergent intervention.
Clinical Examples
📋 Case 1, Anterior STEMI with Cath Lab Activation
Patient: 58M smoker, acute crushing chest pain radiating to left arm × 45 min, diaphoresis, nausea. HR 95, BP 142/88, SpO2 96%.
ECG: ST elevation 3mm in V1–V4 with reciprocal ST depression in II, III, aVF. Anterior STEMI, LAD territory.
Immediate actions (first 10 minutes):
ASA 325 mg chewed + ticagrelor 180 mg PO load
Heparin 60 u/kg IV bolus then 12 u/kg/hr
Cath lab activation, target door-to-balloon <90 min
Cath within 24h → 80% circumflex stenosis, DES placed
Discharge on ABCDE meds. HbA1c optimization. Cardiac rehab
Key lesson: NSTEMI is not benign. Use GRACE/TIMI to identify high-risk patients who benefit from early invasive strategy (<24h). This patient had multiple high-risk features mandating prompt catheterization.
📋 Case 3, Type 2 MI from Demand Ischemia
Patient: 68M admitted for pneumonia/sepsis. HR 128, BP 88/54, SpO2 89% on 4L NC. Febrile to 39.2°C. Known 2-vessel CAD (prior cath showed 60% LAD, 50% RCA).
ECG: Sinus tachycardia, no acute ST changes. Nonspecific T-wave flattening laterally.
Troponin elevation in setting of sepsis + tachycardia + hypotension + hypoxia = classic Type 2 MI (demand ischemia)
No acute plaque rupture, this is supply-demand mismatch from systemic illness
Catheterization is NOT indicated, would not change management and exposes patient to procedural risk
Management:
Treat the underlying cause: IV antibiotics, fluid resuscitation, vasopressors if needed
Supplemental O2 to target SpO2 ≥94%
Hold beta-blocker (hypotensive, septic). Hold ACEi (acute hypotension)
Continue home statin. Trend troponins, expect resolution as sepsis improves
Cardiology consult if troponin continues to rise despite source control, or new ST changes
Key lesson: Not every troponin elevation is a Type 1 MI. The critical question: is there a plaque event, or is there a supply-demand problem? Type 2 MI is treated by fixing the underlying trigger. Reflexive catheterization causes harm.
Monitoring
Parameter
Frequency
Telemetry
Continuous. VT/VF risk highest 24–48h
Troponins
0h, 3h (hs-trop)
ECGs
q15–30min if symptoms persist
Summary
Summary
First 10 Minutes
ECG within 10 minutes of arrival, aspirin 325 mg chewed (chewed for faster absorption), troponin, IV access, continuous telemetry. The ECG is what separates the emergent-reperfusion pathway from everything else, so it comes before the history is finished.
STEMI vs NSTEMI vs Unstable Angina
STEMI: complete occlusion, ST elevation ≥ 1 mm in 2 contiguous leads, troponin positive → emergent PCI. NSTEMI: partial occlusion, ST depression or T inversion, troponin positive → early invasive, 2 to 24 h. Unstable angina: ischemic symptoms with a normal troponin → risk-stratified.
Do Not Miss a STEMI Equivalent
ST elevation is not the only occlusion pattern. New LBBB, de Winter T waves, posterior MI, Wellens syndrome, hyperacute T waves, ST elevation in aVR, high lateral OMI (South African flag sign) and the Aslanger pattern all mean emergent reperfusion despite failing the classic millimeter criteria.
Time Is Myocardium
Door-to-balloon under 90 minutes at a PCI center, under 120 minutes if transferring; if that is not achievable, give fibrinolysis within 30 minutes of arrival. Every 30-minute delay in reperfusion raises 1-year mortality by about 7.5%, which is why EMS should activate the cath lab from the field on a prehospital ECG.
Type 2 MI Is the Common Trap
Type 1 is plaque rupture; type 2 is supply-demand mismatch with no plaque rupture. A troponin rise in a septic, tachycardic inpatient is almost always demand ischemia. Reflexively taking these patients to the cath lab causes harm: treat the sepsis, the anemia or the tachycardia and the troponin follows.
MONA Is Dead
Morphine may increase mortality (it delays and blunts antiplatelet absorption), so use it only for refractory pain. Oxygen only if SpO₂ is below 90%, because routine oxygen in normoxic patients increases infarct size. Nitrates are symptomatic only and are contraindicated in RV infarct, hypotension or recent PDE5 inhibitor use. Aspirin is the part that saves lives.
Risk Scores, Right Score for the Right Decision
HEART is an emergency department disposition score: 0 to 3 low risk (consider discharge), 4 to 6 moderate (admit), 7 to 10 high (early invasive). It does not choose cath timing in a confirmed NSTEMI; that is what GRACE is for.
Prognosis and What Comes After
Killip class at presentation is the strongest single predictor of in-hospital mortality in STEMI, and Killip IV (cardiogenic shock) means emergent PCI plus consideration of mechanical support. Every discharge needs the ABCDE package: antiplatelets and ACE inhibitor, beta blocker, cholesterol (high-intensity statin), diet and diabetes control, exercise via cardiac rehab.
RoundsRx Infographic Series · #58 · Cardiovascular · PDF 154 KB
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CARDIOLOGY · One Pager
ACS Overview (STEMI vs NSTEMI)
The ECG splits the pathway: ST elevation means the artery is occluded now and the cath lab is the treatment, no ST elevation means risk-stratify and cath on a clock.
🧪 First 10 Minutes
ECG within 10 min of chest pain, then troponin. Repeat ECG q15–30 min if the first is normal but symptoms persist, because occlusion can declare itself late.
ASA 325 mg chewed immediately in all ACS unless true allergy. Chewed for faster absorption.
Serial hs-troponin 0h and 3h to catch the rise; a single value cannot distinguish acute from chronic elevation.
Right-sided ECG (V4R) for inferior STEMI before nitrates, because RV infarct is preload-dependent and nitro drops the BP.
Labs: CBC, BMP, coags, BNP, CXR. Bedside: is this Killip I or Killip IV?
⚡ STEMI vs NSTEMI vs Unstable Angina
STEMI: complete occlusion (transmural). ST elevation ≥1 mm in 2 contiguous leads or new LBBB, troponin elevated. 30-day mortality ~6–8%. Emergent PCI.
NSTEMI: partial occlusion / subtotal thrombus. ST depression, T-wave inversion or nonspecific ECG, troponin elevated. 30-day mortality ~3–5%. Early invasive 2–24 h or ischemia-guided.
Unstable angina: partial occlusion, no necrosis. Normal or nonspecific ECG, troponin normal. Mortality <1%. Risk-stratified approach.
STEMI equivalents get the same emergent reperfusion: new LBBB, de Winter T-waves, posterior MI, Wellens syndrome, hyperacute T waves, ST elevation in aVR, high lateral OMI, Aslanger pattern.
Type 2 MI (supply-demand mismatch from tachycardia, anemia, sepsis, hypotension) is treated by fixing the trigger, not by cath, because there is no plaque to open.
🚨 Management, Step by Step
1
ASA 325 mg chewed + anticoagulate: UFH 60 u/kg bolus then 12 u/kg/hr (or enoxaparin 1 mg/kg q12h). Stops thrombus propagation while you arrange reperfusion.
2
Read the ECG and commit: ST elevation means activate the cath lab immediately, ideally from EMS on the prehospital ECG, because every 30 min of delay raises 1-year mortality by 7.5%.
3
STEMI pathway: PCI-capable center, door-to-balloon <90 min (goal <60 min for walk-ins). Transfer, first-medical-contact-to-device <120 min. If that is not achievable, fibrinolysis with door-to-needle <30 min, rescue PCI if no ST resolution by 60–90 min.
4
NSTEMI pathway: risk-stratify. Early invasive 2–24 h if refractory angina, hemodynamic instability, new HF, or GRACE >140. Ischemia-guided cath only if low risk, no recurrent symptoms, negative stress test.
5
Load P2Y12 and statin: ticagrelor 180 mg (preferred) and atorvastatin 80 mg immediately. High-intensity statin on day 1 is unchanged in 2025.
6
Discharge on ABCDE: ACEi (start within 24 h if stable; prevents remodeling), Beta-blocker (within 24 h if stable; reduces arrhythmia and mortality), Cholesterol/statin (target LDL <70), Dual antiplatelet ×12 mo, Eplerenone if EF ≤40% with HF or DM. Add cardiac rehab and smoking cessation.
💊 Key Drugs
Aspirin325 mg chew, then 81 mg daily lifelong
Ticagrelor180 mg load, 90 mg BID ×12 mo; preferred P2Y12, reversible, pair with ASA 81 mg only
Prasugrel60 mg load, 10 mg daily; STEMI going to PCI. Avoid if prior stroke/TIA, age ≥75, wt <60 kg
Clopidogrel600 mg (PCI) or 300 mg load, 75 mg daily; alternative, weaker in CYP2C19 poor metabolizers
Heparin (UFH)60 u/kg bolus, 12 u/kg/hr; aPTT 1.5–2.5× control
Nitroglycerin0.4 mg SL q5min ×3. Avoid in RV infarct, SBP <90, PDE5i use
Cangrelor30 mcg/kg IV bolus then 4 mcg/kg/min; IV P2Y12 for NPO patients in the cath lab, immediate on/off
📊 Monitoring
Continuous telemetry: VT/VF risk is highest in the first 24–48 h post-infarct.
hs-troponin at 0h and 3h: a rising pattern separates acute injury from chronic elevation.
Repeat ECG q15–30 min while symptoms persist: catches evolving ST elevation the first tracing missed.
Echo before discharge: EF drives whether ACEi, MRA, and ICD discussion are indicated (EF ≤40%).
K⁺ and Cr on eplerenone: MRAs cause hyperkalemia and creatinine rise.
Killip class at presentation is the single strongest predictor of in-hospital mortality in STEMI (I ~6%, II ~17%, III ~38%, IV ~67%).
⚠️ Pitfalls
Nitroglycerin in inferior STEMI without checking V4R. The RV is preload-dependent, so venodilation causes profound hypotension. Give IV fluids instead.
Reflexively cathing a Type 2 MI. Troponin elevation in a septic tachycardic patient is almost always demand ischemia; catheterization exposes them to procedural risk without changing management.
Applying HEART to an admitted NSTEMI to pick cath timing. HEART is an ED disposition score. GRACE >140 is what drives early invasive <24 h.
MONA is dead. Morphine may increase mortality in ACS (use only for refractory pain) and oxygen is only for SpO₂ <90%, because hyperoxia may increase infarct size.
Routine upstream GP IIb/IIIa. Strongest antiplatelet but biggest bleeding risk; bailout only for high thrombus burden.
Fondaparinux alone does NOT cover PCI (catheter thrombosis risk). Add a UFH bolus at cath.
🏥 Risk Scores: Which Score, Which Decision
HEART, ED chest pain disposition only. 0–3 low (consider discharge), 4–6 moderate (admit), 7–10 high (early invasive).
GRACE, NSTEMI invasive timing. <108 low (<1% death), 109–140 intermediate, >140 high (>3%) so cath <24 h. Preferred per ESC.
TIMI (NSTEMI/UA), simpler alternative. 0–2 low (5%), 3–4 intermediate, 5–7 high (41%) so early invasive.
Killip IV = cardiogenic shock: emergent PCI plus consider mechanical support and transfer to a shock center.
Escalate immediately for: refractory angina, hemodynamic instability, new heart failure, or sustained ventricular arrhythmia, regardless of score.
🎓 Key Evidence and 2025 Changes
2025 ACC/AHA/ACEP/NAEMSP/SCAI guideline replaces the 2013 STEMI and 2014 NSTE-ACS guidelines. Biggest behavior changes: shorter DAPT with ticagrelor monotherapy, and short-course triple therapy in AFib + PCI.
DAPT after PCI (CHANGED): 1 month DAPT then ticagrelor monotherapy (Class 1, LOE A); 12 months remains the default if not at high bleeding risk. TWILIGHT, 2019
AFib + PCI (CHANGED): triple therapy 1 to 4 weeks, drop the aspirin, then OAC + clopidogrel through month 12, then OAC alone. AUGUSTUS, 2019
Multivessel disease (CHANGED): complete revascularization is now Class 1 over culprit-only. COMPLETE, 2019
Cardiogenic shock (NEW): microaxial flow pump reasonable in selected AMI shock (Class 2a); transfer to a shock center is Class 1. DanGer Shock, 2024
Ticagrelor over clopidogrel:PLATO, 2009. Radial over femoral is Class 1. NSTEMI early invasive in high risk:TIMACS, 2009
Most common valvular disease. Classic triad: syncope, angina, heart failure. Once symptoms develop, prognosis is poor without valve replacement. Medical therapy does NOT change outcomes.
Once ANY symptom develops, mortality is steep. Asymptomatic patients have near-normal survival. The onset of symptoms is the critical inflection point, refer for valve replacement immediately.
Location: Best heard at right upper sternal border (RUSB, aortic area)
Radiation: To carotids bilaterally. Gallavardin phenomenon: may radiate to apex and mimic MR
Severity clues: Late-peaking murmur = more severe. Soft/absent A2 = severely calcified, immobile valve. Paradoxical splitting of S2
Pulsus parvus et tardus: Carotid pulse with diminished amplitude (parvus) and delayed upstroke (tardus), hallmark of significant AS
Maneuvers: Murmur ↓ with Valsalva and standing (except HCM, which ↑). This helps distinguish AS from HOCM
High-yield distinction: AS murmur decreases with Valsalva. HOCM murmur increases with Valsalva. Both are systolic crescendo-decrescendo murmurs, this maneuver is the key differentiator on boards and rounds.
Workup
Workup
TTE, gold standard for diagnosis and severity
ECG: LVH, LAE
BNP if HF symptoms
Cardiac cath: pre-op coronary assessment
RoundsRx Licensed Content - Unauthorized Use ProhibitedManagement
Management
Scenario
Management
Asymptomatic severe
Serial echo q6–12mo. Exercise testing if questionable
Symptomatic severe
VALVE REPLACEMENT (TAVR or SAVR)
High surgical risk
TAVR PARTNER Trials
Low risk / young
SAVR
No medical substitute for valve replacement. Diuretics may help symptoms but do not change natural history.
🔄 Updated Practice: Old teaching: balloon aortic valvuloplasty (BAV) as treatment for severe AS. Current practice: BAV is a temporary bridge only, restenosis occurs within 6-12 months in nearly all patients. TAVR (transcatheter aortic valve replacement) has revolutionized AS management (PARTNER trials). TAVR is now approved for all surgical risk categories and is the standard for high/intermediate-risk patients.
TAVR vs SAVR Indications
Factor
Favors TAVR
Favors SAVR
Age
≥65–70 years
<65 years (durability concerns)
Surgical risk
High/intermediate STS score
Low STS score
Anatomy
Suitable vascular access, favorable anatomy
Bicuspid valve, small annulus, unsuitable access
Concomitant disease
Frailty, porcelain aorta, prior chest radiation
Concurrent CABG or other valve surgery needed
Valve durability
10–15 year data emerging PARTNER 3, 2019
20–25 year durability established
Complications
Lower bleeding, AKI, AF risk
Lower paravalvular leak, pacemaker rate
Recovery
Shorter hospitalization (1–3 days)
Longer recovery (5–7 days inpatient)
Shared decision-making: All patients with severe symptomatic AS should be discussed by a multidisciplinary Heart Valve Team. The choice between TAVR and SAVR depends on anatomy, life expectancy, comorbidities, and patient preference. Evolut Low Risk, 2019
Low-Flow, Low-Gradient AS
Diagnostic challenge: AVA <1.0 cm² but mean gradient <40 mmHg. Two scenarios:
Type
EF
Mechanism
Key Test
Classical (low EF)
<50%
Weak LV cannot generate gradient
Dobutamine stress echo, true severe AS: AVA stays <1.0, gradient rises. Pseudo-severe: AVA increases >1.0
Paradoxical (preserved EF)
≥50%
Small, hypertrophied LV with low stroke volume
Indexed AVA <0.6 cm²/m², stroke volume index <35 mL/m². CT calcium scoring aids diagnosis
Medications
Temporizing
Drug
Role
Caution
Furosemide
Symptom relief
Low doses. Aggressive diuresis → hypotension
ACEi/ARB
If concurrent HTN
Start very low. Dangerous hypotension in severe AS
On Rounds
Classic murmur of AS?
Crescendo-decrescendo systolic at RUSB, radiates to carotids. Late peaking = more severe. Pulsus parvus et tardus. Diminished A2.
Survival estimates once symptoms develop?
Without valve replacement: Angina ~5y, Syncope ~3y, HF ~2y. Steep mortality curve once any symptom appears.
How do you distinguish AS from HOCM on physical exam?
Both produce crescendo-decrescendo systolic murmurs. Key difference: Valsalva/standing, AS murmur decreases (less preload = less flow across valve), HOCM murmur increases (less preload = worse obstruction). Also, AS radiates to carotids with pulsus parvus et tardus; HOCM has a brisk, bifid carotid upstroke.
What is low-flow, low-gradient AS and how do you work it up?
AVA <1.0 cm² but mean gradient <40 mmHg. Classical type: Low EF (<50%), weak LV cannot generate gradient. Use dobutamine stress echo: true severe AS = AVA stays <1.0 with rising gradient; pseudo-severe = AVA opens >1.0. Paradoxical type: Normal EF but small hypertrophied LV with low stroke volume. Diagnosed by stroke volume index <35 mL/m² and CT aortic valve calcium scoring.
What are the major complications of TAVR?
Key TAVR complications: (1) Paravalvular leak, most common, due to incomplete seal between prosthesis and native annulus, (2) Conduction abnormalities, new LBBB or complete heart block requiring permanent pacemaker (~10–20%), (3) Vascular access complications, iliac/femoral injury, (4) Stroke, embolic risk from catheter manipulation, (5) Coronary obstruction, rare but catastrophic.
Why is exercise testing contraindicated in symptomatic severe AS?
Exercise causes peripheral vasodilation with a fixed cardiac output (cannot increase CO across severely stenotic valve). This mismatch → profound hypotension, syncope, ventricular arrhythmias, or sudden death. Exercise testing is ONLY appropriate in asymptomatic severe AS to unmask occult symptoms or an abnormal BP response.
What is the Gallavardin phenomenon?
The AS murmur sometimes has two components: the typical harsh, low-frequency murmur at RUSB radiating to carotids, AND a higher-pitched, musical component heard best at the apex. The apical component can mimic mitral regurgitation. This is a pitfall on physical exam, always check for radiation to carotids and pulsus parvus et tardus to avoid misdiagnosing AS as MR.
What is the most common cause of AS in patients under 65?
Bicuspid aortic valve, present in ~1–2% of the population (most common congenital cardiac anomaly). Develops premature calcification and stenosis, typically presenting 10–20 years earlier than degenerative AS. Associated with aortopathy (ascending aortic dilation, increased dissection risk), must image the ascending aorta.
Clinical Examples
📋 Case 1, Severe Symptomatic AS
Patient: 78M with progressive exertional dyspnea and two episodes of exertional near-syncope over 3 months. Known moderate AS on echo 2 years ago.
Exam: Late-peaking crescendo-decrescendo systolic murmur at RUSB radiating to carotids. Pulsus parvus et tardus. S4 gallop. Soft A2.
Echo: AVA 0.7 cm², mean gradient 52 mmHg, Vmax 4.8 m/s. LVEF 55%. Concentric LVH.
Management:
Severe symptomatic AS, Class I indication for valve replacement
STS score 6.2% (intermediate risk). Heart Valve Team discussion
CT angiography: suitable femoral access, no porcelain aorta
Proceeded with TAVR (transfemoral approach) PARTNER 2, 2016
Discharged day 2 on dual antiplatelet therapy (aspirin + clopidogrel x 3–6 months)
Teaching point: Classic presentation of severe symptomatic AS. Once symptoms develop, do not delay referral, survival drops steeply without intervention. TAVR is preferred for intermediate and high-risk patients.
📋 Case 2, Low-Flow, Low-Gradient AS
Patient: 72F with ischemic cardiomyopathy (EF 30%) and worsening HF symptoms despite optimal GDMT. Echo shows AVA 0.8 cm² but mean gradient only 22 mmHg.
Diagnostic dilemma: Is this true severe AS or pseudo-severe AS (valve appears stenotic because weak LV cannot open it fully)?
Workup:
Dobutamine stress echo: At peak dose, gradient increased to 48 mmHg, AVA remained 0.8 cm² = true severe AS
If AVA had increased >1.0 cm² = pseudo-severe (valve not intrinsically stenotic)
CT aortic valve calcium score: 1,850 AU (confirms severe calcification)
Management: Confirmed true severe AS with low EF. High surgical risk, proceeded with TAVR. Post-procedure, EF improved to 40% at 6-month follow-up (afterload reduction effect).
Teaching point: Low gradient does NOT exclude severe AS in patients with low EF. Dobutamine stress echo is the key test. CT calcium scoring provides complementary evidence.
📋 Case 3, Asymptomatic Severe AS
Patient: 68M, incidental finding of severe AS on echo done for AF workup. AVA 0.9 cm², mean gradient 45 mmHg, Vmax 4.2 m/s. LVEF 65%. Patient denies all symptoms.
Question: Should he undergo valve replacement now?
Workup:
Exercise stress test (appropriate in asymptomatic severe AS): Patient developed exertional dyspnea at 4 METs with SBP drop of 15 mmHg
Abnormal BP response = occult symptom = indication for intervention
BNP elevated at 380 pg/mL (suggests subclinical LV decompensation)
Management: Despite self-reported absence of symptoms, exercise test unmasked abnormal hemodynamic response. Referred for SAVR (age 68, low STS risk score 1.8%, long life expectancy favoring durable surgical valve).
Teaching point: Asymptomatic severe AS patients may be unknowingly limiting activity. Exercise testing can unmask symptoms and abnormal BP response. An abnormal BP response (failure to rise or drop >10 mmHg) is a Class IIa indication for AVR. Younger, low-risk patients generally favor SAVR for long-term durability.
Monitoring
Parameter
Frequency
Echo
q6–12mo severe; q1–2y moderate
Symptoms
Every visit. New symptoms = refer for valve replacement
Summary
Summary
Recognize It
The most common valvular disease. Classic triad of angina, syncope and heart failure. Murmur is crescendo-decrescendo, radiating to the carotids, with a delayed and diminished carotid upstroke in severe disease.
Severity on Echo
Severe: valve area < 1.0 cm², mean gradient > 40 mmHg, or peak velocity > 4.0 m/s. Moderate is 1.0 to 1.5 cm², gradient 25 to 40, velocity 3.0 to 4.0.
Symptoms Are the Inflection Point
Asymptomatic severe AS has near-normal survival; the moment symptoms appear the curve falls off a cliff. Untreated mean survival is roughly 5 years with angina, 3 with syncope and 2 with heart failure. Any new symptom means refer for valve replacement now, not at the next clinic visit.
No Medical Substitute
Nothing medical changes the natural history. Diuretics may ease congestion but do not alter outcome. Valve replacement is the only treatment.
The Dangerous Drug Error
Do not aggressively vasodilate severe AS. These patients are preload-dependent with a fixed cardiac output, so they cannot compensate for a drop in systemic resistance: vasodilation leads to syncope and death. Use nitrates, ACE inhibitors and propofol with great caution.
TAVR or SAVR
Decided by a multidisciplinary Heart Valve Team. High surgical risk or older age favors TAVR (PARTNER trials); younger, lower-risk patients and those needing other cardiac surgery favor SAVR, which also matters for valve durability. Anatomy, life expectancy and patient preference all feed the decision.
Balloon Valvuloplasty Is Only a Bridge
Old teaching treated BAV as definitive; it is not. Restenosis occurs within 6 to 12 months in nearly all patients, so it is a temporizing measure to get someone to TAVR or surgery.
Two Traps
Low-flow, low-gradient AS: a small valve area with a low gradient because the ventricle cannot generate one. Do not call it moderate; get a dobutamine stress echo to unmask true severity. Murmur mimic: the AS murmur decreases with Valsalva while HOCM increases, which is the bedside discriminator.
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CARDIOLOGY · One Pager
Aortic Stenosis and TAVR
Asymptomatic severe AS has near-normal survival; the day a symptom appears the survival curve falls off a cliff, and no medication changes that, only a new valve does.
🧪 Diagnosis and Severity
TTE is the gold standard for both diagnosis and severity grading; everything below comes off the echo.
Severe AS: AVA <1.0 cm², mean gradient >40 mmHg, Vmax >4.0 m/s.
Moderate: AVA 1.0–1.5, mean gradient 25–40, Vmax 3.0–4.0. Mild: AVA >1.5, gradient <25, Vmax <3.0.
Murmur: crescendo-decrescendo systolic at the right upper sternal border radiating to both carotids. Late-peaking means more severe; a soft or absent A2 means a heavily calcified immobile valve.
Pulsus parvus et tardus (low amplitude, delayed upstroke) is the hallmark of significant AS on the carotid exam.
Supporting workup: ECG for LVH and LAE, BNP if HF symptoms, cardiac cath for pre-op coronary assessment before valve surgery.
⚡ Causes and the Symptom Clock
Degenerative / calcific is the leading cause in the elderly. Bicuspid aortic valve is the cause in younger patients (~1–2% of the population), presenting 10–20 years earlier and carrying aortopathy, so image the ascending aorta.
Triad is SAD: Syncope, Angina, Dyspnea (heart failure).
Angina, mean survival ~5 years without AVR. LVH raises O₂ demand while coronary perfusion pressure falls.
Syncope, ~3 years. Fixed cardiac output plus exercise-induced peripheral vasodilation means cerebral hypoperfusion.
Heart failure, ~2 years. Chronic pressure overload leads to systolic dysfunction and decompensation.
The onset of symptoms is the inflection point. Asymptomatic patients have near-normal survival, so refer the moment a symptom appears.
🚨 Management, Step by Step
1
Confirm severity on TTE and ask the one question that drives everything: is the patient symptomatic? Medical therapy does not change the natural history, so the decision is timing of valve replacement.
2
Symptomatic severe AS: valve replacement, TAVR or SAVR. Do not delay, because survival drops steeply once symptoms begin.
3
Asymptomatic severe AS: serial echo q6–12 months, plus exercise testing if the symptom history is questionable, because patients often unknowingly limit activity. An abnormal BP response (failure to rise or a drop >10 mmHg) counts as an occult symptom.
4
Low-flow, low-gradient AS (AVA <1.0 with mean gradient <40): sort out true severe from pseudo-severe before committing to a valve. See the block below.
5
Heart Valve Team decides TAVR vs SAVR using STS risk, anatomy, life expectancy, comorbidity, and patient preference. Every severe symptomatic AS patient should get this multidisciplinary discussion.
🧿 TAVR vs SAVR
Favors TAVR: age ≥65–70, high or intermediate STS score, suitable vascular access, frailty, porcelain aorta, prior chest radiation.
Favors SAVR: age <65 (durability), low STS score, bicuspid valve, small annulus, unsuitable access, or concurrent CABG / other valve surgery needed.
Durability: TAVR has 10–15 year data emerging; SAVR has 20–25 year durability established, which is why younger patients lean surgical.
Trade-offs: TAVR has less bleeding, AKI, and AF; SAVR has less paravalvular leak and a lower pacemaker rate.
Recovery: TAVR 1–3 days in hospital vs SAVR 5–7 days inpatient.
📊 Low-Flow, Low-Gradient and Monitoring
Classical (EF <50%): the weak LV cannot generate a gradient. Dobutamine stress echo settles it: true severe AS keeps AVA <1.0 while the gradient rises; pseudo-severe opens the AVA >1.0.
Paradoxical (EF ≥50%): a small hypertrophied LV with low stroke volume. Look for indexed AVA <0.6 cm²/m² and stroke volume index <35 mL/m²; CT calcium scoring adds supporting evidence.
Echo q6–12 months for severe AS, q1–2 years for moderate, to catch progression before the patient decompensates.
Ask about symptoms every visit. A new symptom is itself the referral trigger for valve replacement.
⚠️ Pitfalls
Aggressive vasodilators in severe AS. These patients are preload-dependent, so vasodilation leads to syncope and death. Start ACEi/ARB very low if HTN coexists.
Exercise testing in a symptomatic patient. Fixed cardiac output plus exercise vasodilation causes profound hypotension, syncope, arrhythmia, or sudden death. It is only for asymptomatic severe AS.
Calling a low gradient "not severe" when the EF is low. Get the dobutamine stress echo before dismissing it.
Mistaking AS for MR (Gallavardin phenomenon) when the murmur radiates to the apex. Check carotid radiation and pulsus parvus et tardus.
Mistaking AS for HOCM. The AS murmur decreases with Valsalva and standing; HOCM increases. HOCM also has a brisk bifid carotid upstroke.
Treating balloon aortic valvuloplasty as definitive. It is a temporary bridge only; restenosis occurs within 6–12 months in nearly all patients.
🏥 Refer for Valve Replacement When
Any symptom in severe AS (syncope, angina, dyspnea). This is the Class I indication and it does not wait for the next echo.
Asymptomatic severe AS with an abnormal exercise BP response (failure to rise or a drop >10 mmHg), which is a Class IIa indication for AVR because it unmasks occult limitation.
Confirmed true severe low-flow low-gradient AS on dobutamine stress echo, even though the resting gradient looks unimpressive.
Known TAVR complications to counsel and watch for: paravalvular leak (most common), conduction disease with new LBBB or complete heart block needing a permanent pacemaker (~10–20%), vascular access injury, stroke, and rare but catastrophic coronary obstruction.
🎓 Key Evidence
PARTNER Trials: established TAVR as non-inferior or superior to SAVR in high and intermediate surgical risk, which is why TAVR is now the standard for those groups.
PARTNER 2, 2016: TAVR non-inferior to SAVR in intermediate-risk patients.
PARTNER 3, 2019: TAVR non-inferior to SAVR at 5 years in low-risk patients, the basis for the emerging 10–15 year durability picture.
Evolut Low Risk, 2019: TAVR non-inferior to SAVR at 2 years in low-risk patients; TAVR is now approved across all surgical risk categories, which is exactly why the Heart Valve Team, not a single number, makes the call.
No trial supports medical therapy as a substitute. Diuretics ease symptoms but do not alter the natural history.
Acute MR (papillary rupture, endocarditis) = surgical emergency with flash pulmonary edema. Chronic MR is insidious, EF is misleadingly preserved. EF 60% in severe MR = significant dysfunction.
EF in MR is misleading. LV ejects into low-pressure LA → EF artificially preserved. EF 60% in severe MR = significant dysfunction. Don’t wait for 40%.
Acute vs Chronic MR, Detailed Comparison
Feature
Acute MR
Chronic MR
LA size
Normal (no time to dilate)
Enlarged (compensatory dilation)
LA pressure
Markedly elevated → pulmonary edema
Only mildly elevated (compliant LA absorbs volume)
LV size
Normal
Dilated (eccentric hypertrophy from volume overload)
Murmur
May be soft/absent (equalization of pressures) or decrescendo
Holosystolic, blowing, radiates to axilla
Hemodynamics
Cardiogenic shock, pulmonary edema
Gradual decompensation over years
CXR
Flash pulmonary edema, normal heart size
Cardiomegaly, chronic congestion
Urgency
Surgical emergency. Stabilize with nitroprusside/IABP
Elective surgery when criteria met
Acute MR pearl: A patient with sudden flash pulmonary edema + normal-sized heart on CXR + new murmur = acute MR until proven otherwise. Most commonly post-MI (papillary muscle rupture, typically 3–7 days after inferior MI affecting posteromedial papillary muscle).
MR Severity Grading
Parameter
Mild
Moderate
Severe
Regurgitant volume (mL/beat)
<30
30–59
≥60
Regurgitant fraction (%)
<30
30–49
≥50
EROA (cm²)
<0.20
0.20–0.39
≥0.40
Vena contracta (cm)
<0.3
0.3–0.69
≥0.7
Color jet area
Small, central
Moderate
Large (>40% LA area) or wall-hugging eccentric jet
Eccentric jets are deceptive. Wall-hugging (Coanda effect) jets appear smaller on color Doppler than their true severity. Always use quantitative measures (EROA, regurgitant volume) rather than relying on color jet area alone.
Optimize GDMT first; MitraClip if persistent COAPT, 2018
Workup
Workup
TTE (severity, LV size/function), TEE for surgical planning
ECG: Afib common
CXR, BNP
Cardiac cath pre-op
Management
Surgery Indications (Chronic Primary MR)
Indication
Action
Symptomatic severe MR
Surgery (repair > replacement)
Asymptomatic + EF ≤60%
Surgery
Asymptomatic + LVESD ≥40mm
Surgery
Secondary MR + HFrEF
MitraClip if on optimal GDMT COAPT 2018
Asymptomatic + new AF
Consider surgery (Class IIa)
Asymptomatic + pulm HTN
PASP >50 mmHg at rest, consider surgery (Class IIa)
Repair > Replacement. Mitral valve repair has lower operative mortality, better LV function preservation, and avoids lifelong anticoagulation. Repair success rates >95% at experienced centers for degenerative MR (posterior leaflet prolapse). Always refer to a surgeon with high repair volume.
Moderate-severe to severe (EROA ≥0.3 cm², regurgitant volume ≥45 mL)
Symptoms
NYHA II–IVa despite optimal GDMT
LVEF
20–50%
LVESD
≤70 mm
GDMT
Must be on maximally tolerated guideline-directed medical therapy
Anatomy
Suitable valve morphology for clip placement (assessed by TEE)
Heart Team
Deemed prohibitive or high surgical risk
COAPT vs MITRA-FR:COAPT, 2018 showed benefit; MITRA-FR, 2018 did not. Key difference: COAPT enrolled patients with disproportionate MR (severe MR relative to LV size), while MITRA-FR included proportionate MR (LV too dilated for clip to help). Ensure MR severity is disproportionate to LV dilation before referring for MitraClip.
Medications
Medical Therapy
Drug
Role
ACEi/ARB
Afterload reduction. Reduces regurgitant fraction
Diuretics
Volume management
GDMT (HF pillars)
For secondary MR with HF
Nitroprusside
Acute severe MR bridge to surgery (ICU only)
On Rounds
Why is EF misleading in MR?
LV ejects into both aorta AND low-pressure LA → inflated EF. EF 60% with severe MR = significant dysfunction (normal heart would be >70%). Surgery threshold is EF ≤60%, not 40%.
What is the COAPT trial?
MitraClip (transcatheter repair) reduced HF hospitalization and mortality in secondary MR with persistent symptoms despite optimal GDMT. Must optimize HF meds first.
Why is repair preferred over replacement for primary MR?
Mitral valve repair preserves the subvalvular apparatus (chordae + papillary muscles), which is critical for LV function. Repair has lower operative mortality (~1% vs 5–10%), better long-term LV function, no need for lifelong anticoagulation (unlike mechanical replacement), and lower risk of prosthetic valve endocarditis. Posterior leaflet prolapse has >95% repair success rate at experienced centers.
What papillary muscle is more commonly involved in ischemic MR, and why?
The posteromedial papillary muscle is far more commonly affected because it has a single blood supply (from the PDA, a branch of the RCA or LCx). The anterolateral papillary muscle has dual blood supply (LAD + LCx) and is therefore protected from single-vessel ischemia. This is why acute MR from papillary rupture most often occurs after inferior MI.
How do you differentiate primary from secondary MR on echo?
Primary MR: structural valve abnormality visible, flail leaflet, prolapse, perforation, vegetation. Jet direction often eccentric. Secondary (functional) MR: valve leaflets appear structurally normal but with restricted closure due to LV dilation/dysfunction, look for tethering, incomplete coaptation, and central regurgitant jet. LV is dilated with wall motion abnormalities.
What is the Coanda effect and why does it matter in MR assessment?
The Coanda effect describes how an eccentric MR jet adheres to the LA wall and appears smaller on color Doppler than its true severity. Wall-hugging jets are common in flail leaflets and prolapse. This leads to underestimation of MR severity by color jet area. Always use quantitative measures (EROA, regurgitant volume, vena contracta) when you see an eccentric jet, rather than relying on visual jet area.
What are the key differences between COAPT and MITRA-FR trials?
Both studied MitraClip in secondary MR, but reached opposite conclusions. COAPT (positive): enrolled patients with disproportionate MR, severe MR (EROA ≥0.3) with only moderate LV dilation (LVESD ≤70mm). MITRA-FR (negative): enrolled patients with proportionate MR, MR severity matched the degree of LV dilation.
When should you use nitroprusside or IABP in acute MR?
Acute severe MR with hemodynamic instability requires urgent afterload reduction as a bridge to emergency surgery. Nitroprusside (ICU, arterial line monitoring): reduces SVR → more blood goes forward through aorta, less regurgitates into LA. IABP: augments diastolic coronary perfusion + reduces afterload during systole, ideal bridge in post-MI papillary rupture. Neither is definitive treatment, surgery is the only cure.
Clinical Examples
📋 Case 1, Acute MR Post-MI (Papillary Rupture)
Patient: 66M, day 5 post-inferior STEMI (delayed presentation, no reperfusion). Sudden onset severe dyspnea with pink frothy sputum.
Vitals: HR 125, BP 78/52, RR 32, SpO2 82% on NRB.
Exam: New harsh holosystolic murmur at apex radiating to axilla. Bilateral crackles to apices. JVD. Cold, clammy extremities.
CXR: Flash pulmonary edema with normal heart size (classic for acute MR).
Bedside echo: Flail posterior mitral leaflet with severe eccentric MR jet, ruptured posteromedial papillary muscle head. LVEF 40%.
Management:
Intubation for respiratory failure
IABP placed for hemodynamic support (afterload reduction + coronary perfusion augmentation)
Nitroprusside drip initiated with arterial line monitoring
Emergent CT surgery consultation, mitral valve replacement (repair often not feasible with ruptured papillary muscle)
Intraoperative finding: necrotic posteromedial papillary muscle with complete rupture
Teaching point: Papillary rupture is a mechanical complication of MI occurring 3–7 days post-infarct. The posteromedial papillary muscle (single blood supply from PDA) is affected far more often than anterolateral. Normal heart size on CXR + flash pulmonary edema = acute MR. This is a surgical emergency with ~75% mortality without surgery.
📋 Case 2, Chronic Severe MR with Declining EF
Patient: 54F with known myxomatous mitral valve prolapse and severe MR, followed with serial echos. Previously LVEF 68%, LVESD 36mm. Latest echo: LVEF 58%, LVESD 42mm. Patient reports mild exertional dyspnea (NYHA II).
Echo details: Posterior leaflet prolapse (P2 segment), EROA 0.52 cm², regurgitant volume 72 mL, vena contracta 0.8 cm. Moderate LA dilation. New onset AF on ECG.
Decision analysis:
Three independent triggers for surgery: (1) Symptoms (NYHA II dyspnea), (2) EF ≤60% (now 58%), (3) LVESD ≥40mm (now 42mm)
Additionally: new AF is a Class IIa indication
P2 prolapse is the most favorable anatomy for repair (>98% success rate)
Management: Referred for mitral valve repair (not replacement) at a high-volume center. Successful posterior leaflet repair with annuloplasty ring. Post-op echo: trivial residual MR, EF 52% (expected transient drop after eliminating low-resistance LA pathway).
Teaching point: Do not wait for EF to drop to 40%, EF ≤60% in severe MR already represents significant dysfunction. Multiple triggers were present here. P2 prolapse is the ideal repair scenario. Repair at high-volume centers (>25 repairs/year) has superior outcomes.
📋 Case 3, Functional MR in Heart Failure
Patient: 71M with ischemic cardiomyopathy (prior LAD stent), LVEF 28%, on maximally tolerated GDMT (sacubitril/valsartan, carvedilol, spironolactone, dapagliflozin, hydralazine/ISDN). Persistent NYHA III symptoms despite 6 months of optimized therapy.
Echo: Dilated LV (LVESD 58mm), severe functional MR with central jet. Leaflets structurally normal but tethered with incomplete coaptation. EROA 0.35 cm², regurgitant volume 50 mL.
Assessment:
Secondary MR from LV dilation, valve is structurally normal
Already on maximal GDMT with CRT-D in place
COAPT criteria met: EROA ≥0.3, LVEF 20–50%, LVESD ≤70mm, persistent symptoms on optimal therapy
STS score high risk for open surgery
MR appears disproportionate to LV dilation (COAPT phenotype, not MITRA-FR)
Management: Proceeded with MitraClip (transcatheter edge-to-edge repair). Post-procedure: MR reduced to mild, NYHA improved to II, no HF hospitalization at 1-year follow-up. COAPT, 2018
Teaching point: In secondary MR, always optimize GDMT first (including CRT if indicated). MitraClip is reserved for patients with persistent symptoms despite maximal therapy who meet COAPT criteria. The key is ensuring MR is disproportionate to LV size.
Monitoring
Parameter
Frequency
Echo
q6–12mo severe; q1–2y moderate
AF surveillance
ECG at visits
Summary
Summary
Acute MR
Papillary muscle rupture or endocarditis. Surgical emergency with flash pulmonary edema: the left atrium has had no time to dilate, so the regurgitant volume transmits straight to the lungs. A new murmur with shock days after an MI is papillary rupture until echo says otherwise.
Primary vs Secondary
Primary: the valve is diseased (prolapse, flail, endocarditis, rheumatic, radiation) and surgery is the treatment. Secondary: the valve is normal and the ventricle is the problem, so GDMT comes first.
The EF Trap
EF is misleadingly preserved in MR, because the ventricle ejects partly into a low-pressure atrium rather than against systemic afterload. An EF of 60% in severe MR already signals significant dysfunction; waiting for a low EF means operating late on an irreversibly damaged ventricle.
When to Operate
Symptomatic severe MR → surgery. Asymptomatic with EF ≤ 60% or LVESD ≥ 40 mm → surgery, because both mark early decompensation. New atrial fibrillation also tips the decision. Repair beats replacement, so refer to a center that repairs.
MitraClip, and Who It Helped
For secondary MR already on optimal GDMT. COAPT, 2018 was positive while MITRA-FR, 2018 was not: COAPT enrolled disproportionate MR, severe regurgitation with a less dilated ventricle, which is the phenotype that benefits.
Workup
TTE for severity and LV size and function; TEE for mechanism and whether the valve is repairable, which decides where the patient is referred. ECG for AF, which is common. BNP, and cath before surgery.
Biggest Pitfall
Following an asymptomatic patient too long. Symptoms and EF both lag the damage, so serial echo against the LVESD and EF thresholds above is what catches the moment to operate.
RoundsRx Infographic Series · #63 · Cardiovascular · PDF 153 KB
Text version
CARDIOLOGY · One Pager
Mitral Regurgitation
Acute MR is a surgical emergency with flash pulmonary edema and a normal-sized heart; chronic MR is silent for years while a falsely reassuring EF hides real LV dysfunction.
Vena contracta ≥0.7 cm (mild <0.3, moderate 0.3–0.69).
Color jet: large (>40% of LA area) or a wall-hugging eccentric jet.
Workup: TTE for severity and LV size/function, TEE for surgical planning, ECG (AF is common), CXR, BNP, and cardiac cath pre-op.
⚡ Acute vs Chronic, Primary vs Secondary
Acute MR causes: papillary rupture post-MI, endocarditis, chordae rupture. LA is normal size with markedly elevated pressure, so it presents as flash pulmonary edema and cardiogenic shock.
Chronic MR causes: myxomatous (MVP), rheumatic, functional from LV dilation. The compliant dilated LA absorbs the volume, so patients stay asymptomatic for years before dyspnea.
Acute murmur may be soft or absent (pressures equalize) or decrescendo; chronic is holosystolic, blowing, radiating to the axilla.
Primary (degenerative) MR: intrinsic valve disease (myxomatous/MVP, rheumatic, endocarditis, radiation). Treatment is repair, preferred over replacement.
Secondary (functional) MR: structurally normal valve, MR driven by LV dilation or dysfunction (ischemic or dilated cardiomyopathy). Optimize GDMT first, MitraClip if MR persists.
Papillary rupture timing: typically 3–7 days after inferior MI, hitting the posteromedial papillary muscle.
🚨 Management, Step by Step
1
Acute severe MR is a surgical emergency. Sudden flash pulmonary edema with a normal-sized heart on CXR plus a new murmur is acute MR until proven otherwise. Get emergent CT surgery involved.
2
Stabilize with afterload reduction as a bridge, not a cure: nitroprusside in the ICU with an arterial line (drops SVR so more blood goes forward through the aorta and less regurgitates into the LA), and IABP (augments diastolic coronary perfusion while reducing systolic afterload), ideal in post-MI papillary rupture.
3
Chronic primary MR: check the three surgical triggers at every echo, symptoms, EF ≤60%, and LVESD ≥40 mm. Any one of them is enough to operate.
4
Send primary MR for repair, not replacement, to a surgeon with high repair volume. Repair preserves the subvalvular apparatus, has lower operative mortality (~1% vs 5–10%), better long-term LV function, no lifelong anticoagulation, and lower prosthetic endocarditis risk.
5
Secondary MR: maximize GDMT first (including CRT if indicated), then consider MitraClip only if symptoms persist and COAPT criteria are met, because the valve itself is not the primary problem.
💊 Medical Therapy
ACEi / ARBafterload reduction, lowers the regurgitant fraction
Diureticsvolume management for congestive symptoms
GDMT (HF pillars)for secondary MR with heart failure; treats the cause, which is the dilated LV
Nitroprussideacute severe MR bridge to surgery, ICU only with arterial line
📊 Monitoring
Echo q6–12 months for severe MR, q1–2 years for moderate, because the surgical triggers (EF, LVESD) are echo findings that appear before the patient feels anything.
ECG at visits for AF surveillance. New AF in asymptomatic severe MR is itself a Class IIa indication for surgery.
Track LVESD and EF as a trend, not a snapshot. A drift from EF 68% to 58% or LVESD 36 mm to 42 mm is the signal to operate even if the patient feels well.
Expect a transient EF drop after repair, because eliminating the low-resistance LA pathway unmasks true LV function.
⚠️ Pitfalls
Waiting for EF to fall to 40% before operating. The LV ejects into the low-pressure LA so EF is artificially inflated; EF 60% in severe MR already means significant dysfunction (a normal heart would be >70%). The surgical threshold is EF ≤60%.
Trusting color jet area in an eccentric jet. Wall-hugging (Coanda effect) jets look smaller than they are, so use quantitative measures (EROA, regurgitant volume, vena contracta).
Missing acute MR because the murmur is quiet. In acute MR, LA and LV pressures equalize, so the murmur can be soft or absent even in cardiogenic shock.
Reading a normal heart size on CXR as reassuring. In flash pulmonary edema it is the classic tell for acute MR (no time for the LA or LV to dilate).
Referring MitraClip for the wrong phenotype. Confirm the MR is disproportionate to LV dilation; proportionate MR in a very dilated LV is the MITRA-FR population that did not benefit.
Defaulting to replacement in degenerative MR. Posterior leaflet prolapse has >95% repair success at experienced centers.
🏥 Refer for Intervention When
Symptomatic severe MR: surgery, repair preferred over replacement.
Asymptomatic with EF ≤60%: surgery, because the EF has already fallen further than the number suggests.
Asymptomatic with LVESD ≥40 mm: surgery, the LV is decompensating structurally.
Asymptomatic with new AF: consider surgery (Class IIa).
Asymptomatic with pulmonary hypertension, PASP >50 mmHg at rest: consider surgery (Class IIa).
Secondary MR with HFrEF on optimal GDMT: MitraClip. COAPT eligibility is EROA ≥0.3 cm² or regurgitant volume ≥45 mL, NYHA II–IVa despite optimal GDMT, LVEF 20–50%, LVESD ≤70 mm, suitable anatomy on TEE, and prohibitive or high surgical risk per the Heart Team.
🎓 Key Evidence
COAPT, 2018: MitraClip reduced HF hospitalization and mortality in secondary MR with persistent symptoms despite optimal GDMT. This is what makes "optimize GDMT first" a prerequisite, not a formality.
MITRA-FR, 2018: no benefit in secondary MR. The difference is the phenotype: COAPT enrolled disproportionate MR (severe MR relative to LV size), MITRA-FR enrolled proportionate MR where the LV was too dilated for a clip to help.
Why the posteromedial papillary muscle ruptures: it has a single blood supply from the PDA, while the anterolateral has dual supply (LAD plus LCx) and is protected from single-vessel ischemia. That is why acute MR follows inferior MI.
Repair volume matters: repair success exceeds 95% at experienced centers for degenerative MR (posterior leaflet prolapse), so where you refer changes the operation the patient gets.
Surgical emergency. “Time is tissue.” The 6 P’s: Pain, Pallor, Pulselessness, Poikilothermia, Paresthesia, Paralysis. Start heparin IMMEDIATELY, call vascular surgery.
Overview
6 P’s
Pain, sudden, severe
Pallor
Pulselessness
Poikilothermia (cold)
Paresthesia
Paralysis (late = bad)
Rutherford Classification
Category
Status
Sensory
Motor
I
Viable
None
None
IIa
Marginally threatened
Minimal
None
IIb
Immediately threatened
Rest pain
Mild-moderate
III
Irreversible → amputation
Anesthetic
Paralysis
SURGICAL EMERGENCY. Start heparin IMMEDIATELY. Do NOT wait for imaging to anticoagulate.
Embolism vs Thrombosis
Feature
Embolism
Thrombosis (in-situ)
Onset
Sudden, dramatic (“bolt from the blue”)
More insidious (hours–days)
History
AF, recent MI, valvular disease, endocarditis
Known PAD, prior bypass/stent, claudication
Contralateral leg
Normal pulses
Often diminished pulses (bilateral PAD)
Location
Bifurcations (femoral, popliteal, aortic saddle)
At site of prior stenosis/graft
Collaterals
Absent (no time to develop)
Present (chronic disease)
Treatment
Embolectomy (Fogarty catheter)
Thrombolysis, angioplasty, or bypass
Clinical Pearl: Embolic ALI → look for AF on ECG (most common source). Always check both legs, normal contralateral pulses suggest embolism; diminished bilateral pulses suggest thrombosis on PAD.
Key Distinction: Rutherford IIa = thrombolysis OK (sensory loss only). Rutherford IIb = motor deficit present = go directly to OR for embolectomy/bypass. Do NOT waste time with catheter-directed thrombolysis.
Reperfusion Injury: After revascularization, watch for the “deadly triad”, hyperkalemia (cardiac arrest risk), rhabdomyolysis (CK >10,000, AKI), and metabolic acidosis. Aggressive IVF, monitor K+ q2h, consider empiric calcium gluconate and sodium bicarbonate.
Medications
Medications
Drug
Dose
Notes
Heparin UFH
80u/kg bolus, 18u/kg/hr
aPTT 60–80s. Prevents clot propagation
tPA (catheter-directed)
0.5–1mg/hr intra-arterial
Rutherford I–IIa. Takes 12–24h
On Rounds
Most common cause of ALI?
Embolism (AF most common source) and in-situ thrombosis (on atherosclerotic disease). Embolic = sudden, no prior claudication. Thrombotic = PAD history, more insidious.
What is the first medication to give in suspected ALI, and why?
Unfractionated heparin (UFH) 80 u/kg bolus → 18 u/kg/hr infusion. Prevents clot propagation distally and proximally while definitive intervention is arranged. Start BEFORE imaging, “time is tissue.”
How do you distinguish Rutherford IIa from IIb, and why does it matter?
IIa = sensory loss only, no motor deficit → catheter-directed thrombolysis is an option. IIb = motor deficit present (cannot wiggle toes) → must go directly to surgical embolectomy or bypass. Thrombolysis takes 12–24h and is too slow for IIb.
Name 3 clinical features that distinguish embolic from thrombotic ALI.
Embolic: (1) sudden onset with no prior claudication, (2) normal contralateral pulses, (3) known AF or recent MI. Thrombotic: (1) history of PAD/claudication, (2) diminished bilateral pulses, (3) prior bypass graft or stent.
What is the “deadly triad” of reperfusion injury after revascularization?
Hyperkalemia (can cause fatal arrhythmia), rhabdomyolysis (CK >10,000, myoglobinuric AKI), and metabolic acidosis (lactic acid washout from ischemic tissue). Treat with aggressive IVF, calcium gluconate, bicarbonate, and monitor K+ q2h.
When should you suspect compartment syndrome post-revascularization, and what is the treatment?
Suspect when there is tense swelling, pain out of proportion, and pain with passive stretch of compartment muscles. Compartment pressure >30 mmHg (or within 30 mmHg of diastolic BP) is diagnostic. Treatment is four-compartment fasciotomy of the affected leg.
Why is Rutherford III considered irreversible, and what is the danger of attempting revascularization?
Rutherford III = anesthetic limb with paralysis, rigor, and mottling. Muscle is already necrotic. Revascularization at this stage causes massive reperfusion injury, washout of potassium, myoglobin, and lactate can cause cardiac arrest, DIC, and multi-organ failure. Primary amputation is indicated.
A patient has ALI and you find AF on ECG. After acute management, what long-term anticoagulation is needed?
AF-related arterial embolism requires lifelong anticoagulation. After acute heparin therapy and intervention, transition to a DOAC (apixaban, rivaroxaban) or warfarin (INR 2–3). Also consider rate vs rhythm control for the AF and evaluate for LA thrombus with TEE. RE-LY, 2009; ARISTOTLE, 2011
Clinical Examples
📋 Case 1, Embolic ALI from Atrial Fibrillation
Patient: 72F with known AF (not on anticoagulation, “refused warfarin”), presents with sudden onset left leg pain, pallor, and coldness 3 hours ago. No prior claudication.
Exam: Left leg pale, cool, no popliteal or pedal pulses. Sensation diminished over foot. Can still weakly dorsiflex toes. Right leg warm with normal pulses.
Classification: Rutherford IIa (sensory loss, minimal motor). Normal contralateral pulses + AF + sudden onset = embolic etiology.
Management:
Heparin 80 u/kg bolus → 18 u/kg/hr started immediately in ED
CTA confirms occlusion at left common femoral artery bifurcation (classic embolic location)
Vascular surgery performs Fogarty balloon embolectomy under local anesthesia
Post-op: monitor for compartment syndrome, K+ q2h, CK trending
Long-term: Started apixaban 5 mg BID for AF (CHA₂DS₂-VASc = 4). Cardiology follow-up
Key lesson: Embolic ALI from AF is preventable with anticoagulation. Fogarty embolectomy is first-line for embolic ALI.
📋 Case 2, Thrombotic ALI in Peripheral Arterial Disease
Patient: 65M with history of PAD (prior right SFA stent 2 years ago), DM2, smoking. Presents with 18 hours of worsening right foot pain and numbness. Reports baseline 1-block claudication.
Exam: Right foot mottled, cool. No pedal pulses. Cannot dorsiflex toes (motor deficit). Left leg has diminished but palpable dorsalis pedis pulse.
Classification: Rutherford IIb (motor deficit). Bilateral diminished pulses + PAD history + gradual onset = thrombotic etiology (likely in-stent thrombosis).
Management:
Heparin bolus + infusion started immediately
Rutherford IIb with motor deficit → NO thrombolysis (too slow). Taken to OR emergently
Intra-op: thrombosed SFA stent with propagation into popliteal. Surgical thrombectomy + fem-pop bypass with reversed saphenous vein graft
Post-op: pedal pulses restored. CK peaked at 8,200. K+ 5.8 → treated with calcium gluconate + insulin/dextrose
Monitored for compartment syndrome, pressures remained <25 mmHg, no fasciotomy needed
ICU admission: Continuous renal replacement therapy (CRRT) initiated for refractory hyperkalemia and acidosis. CK trended downward over 5 days
Fasciotomy wounds closed with split-thickness skin graft at day 7
Key lesson: Reperfusion injury is the “second hit” after revascularization. Longer ischemia time = higher risk. Anticipate hyperK, rhabdo, and compartment syndrome. ICU monitoring is mandatory.
Monitoring
Parameter
Frequency
Pulse checks
q1h
Compartment pressures
Post-reperfusion. >30mmHg → fasciotomy
K+, CK, Cr
q4–6h post-reperfusion
aPTT
q6h
Summary
Summary
Recognize It
Surgical emergency: time is tissue. The 6 P's: pain, pallor, pulselessness, poikilothermia, paresthesia, paralysis. Paresthesia and paralysis are the late two and mark a limb that is already threatened, so do not wait for them to appear.
First Move
Start heparin immediately and call vascular surgery.Do not wait for imaging to anticoagulate: heparin limits clot propagation while the plan is arranged, and the delay to imaging is where limbs are lost.
Rutherford Class Decides the Treatment
I viable (no sensory or motor loss) → heparin, angiography within hours. IIa marginally threatened (sensory loss only) → catheter-directed thrombolysis is acceptable. IIb immediately threatened (motor deficit) → straight to the operating room. III (anesthetic, paralyzed) → irreversible, amputation.
The Class That Catches People
IIa versus IIb is the whole decision.Any motor deficit makes it IIb, and thrombolysis takes hours the limb does not have. Do not spend that time on a lytic catheter: embolectomy or bypass now.
Embolism or Thrombosis
Embolism: sudden onset, a source such as AF or recent MI, normal pulses in the other leg, no collaterals, lodges at bifurcations → Fogarty embolectomy. In-situ thrombosis: more insidious over hours to days, known PAD or prior bypass, diminished pulses bilaterally, collaterals present → thrombolysis, angioplasty or bypass.
Always Examine Both Legs
The contralateral leg is the single most useful physical finding. Normal pulses on the other side point to embolism; diminished pulses on both point to thrombosis on background PAD, and the two have different operations.
Reperfusion Is Its Own Emergency
After revascularization watch the deadly triad: hyperkalemia (risk of cardiac arrest), rhabdomyolysis with CK above 10,000 and AKI, and metabolic acidosis. Aggressive IV fluids, potassium every 2 h, and monitor for compartment syndrome, which may need fasciotomy.
Find the Source
ECG for atrial fibrillation, which is the commonest embolic source, plus echo for thrombus or endocarditis. Long-term anticoagulation for embolic disease, and secondary prevention for atherosclerosis if it was in-situ thrombosis.
Dilated proximal bowel → decompressed distal bowel. Identifies the site of obstruction. Distinguishes SBO from ileus (no transition point in ileus).
Air-fluid levels
Multiple, differential levels on upright film. Stepladder pattern classic for SBO.
Small bowel feces sign
Particulate matter in dilated SB near transition point. Suggests prolonged obstruction with bacterial overgrowth.
Closed-loop obstruction
U-shaped or C-shaped dilated loop with 2 transition points converging. HIGH risk of strangulation → surgical emergency.
Pneumatosis intestinalis
Air within bowel wall = ischemia/necrosis. Requires urgent surgery.
Portal venous gas
Air in portal system = bowel necrosis. Extremely ominous sign. Emergency laparotomy.
Mesenteric haziness / stranding
Suggests venous congestion or early ischemia. Correlate with lactate.
Whirl sign
Swirling of mesentery and bowel around a point = volvulus or internal hernia.
Signs of Strangulation on CT (GO TO OR): Closed-loop obstruction, pneumatosis intestinalis, portal venous gas, mesenteric haziness with non-enhancing bowel wall, free fluid, and whirl sign. Any of these = do NOT attempt conservative management.
Conservative vs Operative Management
Criteria
Conservative (Trial of Non-Op)
Operative (Go to OR)
Obstruction type
Partial SBO (contrast passes on CT)
Complete SBO, any LBO with obstruction
Etiology
Adhesive SBO (no virgin abdomen)
Hernia, closed-loop, volvulus, tumor
Clinical status
Stable, no peritonitis, tolerating NGT
Peritonitis, sepsis, hemodynamic instability
Labs
Normal lactate, normal WBC
Elevated lactate, leukocytosis, acidosis
Imaging
No closed-loop, no pneumatosis, no portal gas
Any sign of strangulation or ischemia
Time frame
Resolution expected within 48–72h
Failure to improve after 48–72h of conservative Rx
Workup
Workup
CT abdomen/pelvis with IV contrast, gold standard. Look for transition point, closed-loop, pneumatosis, portal venous gas
CBC, BMP, lactate, lipase, type and screen
Upright CXR if free air suspected (perforation)
AXR: stepladder air-fluid levels (SBO), dilated colon >6 cm or cecum >9–12 cm (LBO)
Management
Conservative (Partial SBO)
NGT decompression, NPO, IVF, serial exams q4–8h
Gastrografin (diagnostic + therapeutic: reaches colon on 24h film = resolving)
Surgery Indications
Complete obstruction, strangulation, closed-loop, failure to resolve 48–72h, incarcerated hernia
🔄 Updated Practice: Old teaching: mandatory nasogastric tube (NGT) decompression for all small bowel obstruction. Current practice: NGT is indicated for patients with significant vomiting, distension, or complete obstruction. Mild partial SBO with minimal symptoms can be managed with bowel rest, IV fluids, and observation without NGT. Water-soluble contrast (Gastrografin) challenge at 24-48h can be both diagnostic and therapeutic, appearance of contrast in the colon predicts resolution without surgery.
Gastrografin Challenge Protocol
Step
Action
Details
1
Confirm appropriateness
Partial adhesive SBO, no signs of strangulation, no complete obstruction, no peritonitis
2
Administer Gastrografin
100 mL water-soluble contrast via NGT (or PO if no NGT). Clamp NGT ×2h after administration
3
Abdominal X-ray at 8–24h
Check if contrast has reached the colon/cecum
4a
Contrast in colon = RESOLVING
Advance diet. High negative predictive value for need of surgery (~98%). Defined by Defined, Abbas et al. meta-analysis, 2014
4b
Contrast NOT in colon by 24–48h
Likely requires operative intervention. Surgical consult if not already involved
Why Gastrografin works therapeutically: Hyperosmolar contrast draws fluid into bowel lumen → reduces bowel wall edema → promotes peristalsis past partial obstruction. Do NOT use barium (if perforation occurs, barium peritonitis is fatal; Gastrografin is water-soluble and absorbed).
LBO-Specific Management
Etiology
Acute Management
Definitive Treatment
Colorectal cancer
Colonic stent (bridge to surgery) or diverting colostomy
Oncologic resection with primary anastomosis or Hartmann procedure
Sigmoid volvulus
Endoscopic decompression + rectal tube
Interval sigmoid resection (recurrence rate >50% without surgery)
Cecal volvulus
Surgery (endoscopy does NOT work)
Right hemicolectomy (cecopexy has high recurrence)
Pseudo-obstruction (Ogilvie)
Neostigmine 2 mg IV (monitor for bradycardia). Colonoscopic decompression if fails
Correct underlying cause (post-op, electrolytes, medications)
Cecal diameter >12 cm = perforation risk. If cecum >9–12 cm on imaging in LBO or Ogilvie syndrome, urgent decompression is needed regardless of etiology.
Medications
Medications
Drug
Role
NS / LR
Aggressive volume resuscitation
Gastrografin
100mL via NGT (diagnostic + therapeutic)
Ondansetron
Antiemetic 4mg IV q6h
Pip-tazo / Cefepime + Metro
If strangulation/perforation suspected
On Rounds
SBO vs ileus?
SBO = mechanical (transition point on CT, dilated proximal, decompressed distal). Ileus = functional (diffuse dilation, no transition point). Ileus: post-op, opioids, hypoK, peritonitis.
Why does scope work for sigmoid but not cecal volvulus?
Sigmoid twists at accessible location → sigmoidoscopy can pass tube past twist. Cecal volvulus = cecum twists on mesentery, too proximal for scope. Cecal = surgery (cecopexy or right hemicolectomy).
What is a closed-loop obstruction and why is it dangerous?
A closed-loop obstruction occurs when a segment of bowel is obstructed at two points (e.g., adhesive band trapping a loop). The trapped segment cannot decompress proximally or distally → rapidly increasing intraluminal pressure → venous congestion → arterial compromise → ischemia and necrosis. CT shows U-shaped or C-shaped dilated loop with two adjacent transition points.
What does the Gastrografin challenge tell you, and when should you NOT use it?
Gastrografin in colon by 8–24h = SBO is resolving (98% negative predictive value for surgery). Also therapeutic, hyperosmolar contrast reduces bowel wall edema and promotes peristalsis. Do NOT use if: complete obstruction, signs of strangulation, peritonitis, or suspected perforation. Never use barium (barium peritonitis is fatal if perforation occurs). Abbas et al., Ann Surg, 2014
Name 3 CT findings that indicate bowel ischemia/strangulation and mandate surgery.
(1) Pneumatosis intestinalis, air within bowel wall = necrosis. (2) Portal venous gas, air in portal system, extremely ominous. (3) Non-enhancing bowel wall on IV contrast CT, indicates loss of blood supply. Other concerning signs: closed-loop, mesenteric haziness/free fluid, whirl sign.
What is the #1 cause of LBO and how do you manage malignant LBO acutely?
Colorectal cancer is the #1 cause of LBO. Acute management: colonic stent as a bridge to surgery (allows bowel decompression, optimization of nutritional status, and staging before elective resection) or diverting loop colostomy if stent not feasible. Definitive: oncologic resection. Emergent surgery for LBO carries higher morbidity/mortality vs elective resection after stent decompression.
How do you differentiate SBO from Ogilvie syndrome (acute colonic pseudo-obstruction)?
Ogilvie = massive colonic dilation WITHOUT mechanical obstruction. CT shows dilated colon (often >10 cm) with no transition point and no obstructing lesion. Typically post-operative, critically ill, or electrolyte deranged patients. Treatment: correct underlying cause, neostigmine 2 mg IV (monitor for bradycardia, have atropine ready), or colonoscopic decompression. Surgery if cecum >12 cm or perforation. Ponec et al., NEJM, 1999
A patient with adhesive SBO has been managed conservatively for 72 hours with no improvement. What do you do?
Failure to resolve after 48–72 hours of conservative management is an indication for surgery. Prolonged obstruction increases risk of strangulation, bacterial translocation, and aspiration. If Gastrografin was given and has NOT reached the colon by 48h, this further supports operative intervention. Consult surgery early, delayed surgical intervention in SBO is associated with increased morbidity.
Clinical Examples
📋 Case 1, Adhesive SBO Managed Conservatively
Patient: 54F with history of open appendectomy (20 years ago) and prior cesarean section. Presents with 24 hours of crampy abdominal pain, nausea, bilious vomiting ×4, and obstipation. No prior SBO episodes.
Exam: Abdomen distended, tympanitic, diffusely tender without rebound or guarding. High-pitched bowel sounds. No hernias on exam. Temp 37.1, HR 98, BP 110/70.
CT abdomen/pelvis: Dilated small bowel loops up to 4.5 cm with a transition point in the RLQ at a band adhesion. Decompressed distal ileum and colon. No closed-loop, no pneumatosis, no portal venous gas. Small amount of contrast passes the transition point (partial SBO).
Management:
Conservative: NGT placed (high output, 800 mL in first 4h), NPO, aggressive IVF with LR, K+ repletion
Gastrografin challenge: 100 mL via NGT at 24h. AXR at 8h shows contrast reaching cecum → resolving
NGT output declining. Clears by 36h. NGT removed
Diet advanced: clears → low-residue → regular. Passing flatus and stool by 48h
Discharged day 3 with dietary counseling and return precautions
Key lesson: Partial adhesive SBO without strangulation signs is the ideal candidate for conservative management. Gastrografin reaching the colon by 8–24h has a 98% negative predictive value for need of surgery.
📋 Case 2, Strangulated SBO Requiring OR
Patient: 68M with history of multiple prior abdominal surgeries (cholecystectomy, ventral hernia repair with mesh). Presents with acute-onset severe periumbilical pain ×8 hours, now constant and worsening. Multiple episodes of non-bilious emesis.
Exam: Distended, rigid abdomen with involuntary guarding and rebound tenderness. Absent bowel sounds. Temp 38.9, HR 122, BP 88/54, lactate 6.8.
CT abdomen/pelvis:Closed-loop obstruction in mid-abdomen with C-shaped dilated loop, two adjacent transition points, pneumatosis intestinalis in the affected segment, mesenteric haziness, and small-volume free fluid. No portal venous gas.
Emergency surgery: NO conservative trial, closed-loop + pneumatosis = strangulation. Taken to OR within 2 hours of arrival
Intra-op: Dense adhesive band causing closed-loop. 60 cm of non-viable small bowel (dusky, no peristalsis, no Doppler signal). Small bowel resection with primary anastomosis
Post-op ICU: continued antibiotics, serial lactate (normalized by 12h), nutrition via NG feeds on POD 3
Discharged POD 7 tolerating regular diet
Key lesson: Peritonitis + hemodynamic instability + closed-loop + pneumatosis = NO role for conservative management. These patients need immediate operative intervention. Elevated lactate >4 with leukocytosis strongly suggests bowel ischemia.
📋 Case 3, Malignant LBO with Colonic Stent
Patient: 73M with 3-week history of progressive constipation, abdominal distension, and colicky pain. No BM ×5 days. No prior abdominal surgery. 15 lb weight loss over 2 months.
Exam: Markedly distended abdomen, tympanitic. Mild diffuse tenderness, no peritonitis. Empty rectal vault on DRE. Temp 37.2, HR 90, BP 135/80.
Labs: WBC 11, lactate 1.4, Hgb 9.2 (microcytic, iron deficiency), CEA 28 (elevated).
CT abdomen/pelvis: Dilated colon (cecum 10 cm) with transition point at splenic flexure, circumferential mass causing near-complete LBO. No perforation. Multiple hepatic lesions concerning for metastatic disease. Ileocecal valve competent (no decompression into small bowel).
Management:
Acute decompression: Interventional GI places a self-expanding metal stent (SEMS) across the obstructing lesion via colonoscopy, “bridge to surgery”
Patient begins passing flatus and stool within 12h. Cecal dilation resolves on repeat AXR
MDT discussion: Given metastatic disease, neoadjuvant FOLFOX + bevacizumab started. Elective left hemicolectomy planned after 3–4 cycles if response to chemo
Stent allows nutritional optimization and avoidance of emergent surgery (which carries 15–20% mortality in obstructed CRC vs <5% elective)
Key lesson: Colonic stenting as a bridge to surgery in malignant LBO allows decompression, staging, and optimization before definitive surgery. Emergent surgery for obstructing CRC has significantly higher morbidity and mortality than elective resection. CReST Collaborative, Lancet Oncol, 2022
Monitoring
Parameter
Frequency
Abdominal exam
q4–8h
NGT output
q shift
CBC, lactate
q8–12h
Summary
Summary
Start With Small Bowel or Large Bowel
SBO: adhesions are the number one cause (then hernias, malignancy, Crohn disease), and prior abdominal surgery is the history that gives it away. LBO: colorectal cancer is the number one cause, then volvulus, so every new LBO needs a cancer workup once the obstruction is relieved.
Initial Management Is the Same Four Things
NPO, IV fluids, correct electrolytes, and serial abdominal exams. Third-spacing into obstructed bowel is large and underestimated, so these patients are usually far more volume-depleted than they look.
The NG Tube Is No Longer Automatic
Old teaching was an NG tube for every SBO; current practice is selective. Decompress the patient with significant vomiting, distension or complete obstruction. A mild partial obstruction without vomiting does not need one, and the tube itself causes sinusitis and discomfort.
What Sends Them to the Operating Room
Strangulation is a surgical emergency: fever, peritoneal signs, leukocytosis, rising lactate, free air, or a non-reducible hernia. On CT: closed-loop obstruction, pneumatosis intestinalis, portal venous gas, the whirl sign, free fluid, or a non-enhancing bowel wall.Any one of these means do not attempt conservative management, because the bowel is already ischemic.
Conservative Management Has a Clock
Give an uncomplicated partial SBO 48 to 72 h. Failure to resolve in that window is itself an indication to operate: the ones that were going to open up mostly have by then, and waiting longer just delays surgery on progressively sicker bowel.
Gastrografin Is Both Test and Treatment
Give water-soluble contrast and repeat the abdominal film at 8 to 24 h. Contrast reaching the colon predicts resolution and often produces it. The hyperosmolar contrast pulls fluid into the lumen, reduces bowel wall edema and restarts peristalsis past a partial obstruction. Never use barium: if the bowel perforates, barium peritonitis is catastrophic.
Volvulus Splits by Location
Sigmoid volvulus: scope first. Endoscopic decompression works, and it is followed by interval resection because recurrence is high. Cecal volvulus: surgery. Endoscopic decompression does not work here; the operation is a right hemicolectomy.
Watch the Cecum in Any LBO
A cecal diameter above 12 cm is a perforation risk. The cecum has the thinnest wall and the largest radius, so by Laplace's law it blows first. Anything from 9 to 12 cm needs urgent decompression regardless of the cause, including Ogilvie syndrome.
Rapidly progressive soft tissue infection. Every hour to the operating room matters: delay beyond 24 hours carries roughly a 9-fold higher mortality. Pain OUT OF PROPORTION to exam is the hallmark. Surgical debridement IS the treatment. CT can miss early cases.
If you suspect nec fasc, go to the OR. Do NOT wait for imaging. CT can MISS early disease. The “finger test” (bedside incision, tissue planes dissect easily) is diagnostic. Delay to debridement beyond 24 hours is the threshold most consistently linked to death (relative risk ~9.4 Wong, 2003), so the clock starts the moment you suspect it.
Workup
Workup
Clinical diagnosis, do NOT delay for imaging
Labs: CBC, BMP (Na often low), CRP, lactate, CK, coags, blood cultures
LRINEC score ≥6 suspicious, ≥8 highly suggestive
Finger test: bedside incision, easy tissue dissection = nec fasc
Management
Management
SURGICAL DEBRIDEMENT IS THE TREATMENT, antibiotics are adjunct
Second-look operation 24–48h. Often serial debridements needed
ICU for sepsis management
IVIG for streptococcal toxic shock (1–2 g/kg, controversial but used)
🔄 Updated Practice: Old teaching: obtain CT or MRI to confirm necrotizing fasciitis before consulting surgery. Current practice: if you suspect nec fasc clinically (pain out of proportion, rapidly spreading, systemic toxicity, crepitus), take the patient to the OR immediately. CT can MISS early disease, sensitivity is only ~80%. Delay to debridement beyond 24 hours is independently associated with roughly 9-fold higher mortality (Wong 2003), and the EAST 2018 practice guideline recommends operating as soon as the diagnosis is suspected rather than waiting on imaging. The 'finger test' (bedside wound exploration, if tissue planes dissect easily with blunt finger) is faster and more reliable than imaging.
Medications
Antibiotic Regimen
Drug
Dose
Role
Vancomycin
25–30mg/kg load, 15–20mg/kg q8–12h
MRSA coverage
Piperacillin-Tazobactam
4.5g IV q6h
Broad GN + anaerobe coverage
Clindamycin
900mg IV q8h
TOXIN SUPPRESSION
Clindamycin for TOXIN SUPPRESSION, not just coverage. GAS and Clostridium produce exotoxins driving shock. Clindamycin (protein synthesis inhibitor) stops toxin production. Beta-lactams do NOT suppress toxins.
On Rounds
Why add clindamycin?
Toxin suppression. GAS and Clostridium make exotoxins (superantigens) driving shock. Clindamycin inhibits protein synthesis → stops toxin production. Beta-lactams target cell wall, not protein synthesis.
Can CT rule out nec fasc?
No. CT can miss early disease. Gas/fascial thickening are late findings. If clinical suspicion high, go to OR. Finger test or intraop exploration is diagnostic.
Clinical Examples
📋 Case 1, Type I Polymicrobial Necrotizing Fasciitis
Patient: 62M with T2DM, presents with rapidly expanding erythema and exquisite pain on left lower leg after minor skin break. Temp 39.8°C, HR 128, BP 88/52. WBC 24K, lactate 5.4, Cr 2.8. Skin: dusky discoloration, hemorrhagic bullae, crepitus on palpation.
Key findings: Crepitus = subcutaneous gas (Clostridium or mixed anaerobes). Pain out of proportion to exam appearance. Hemodynamic instability. LRINEC score > 6 (high risk). Type I = polymicrobial (diabetics, immunocompromised).
Management:
Emergent surgical debridement, this is the ONLY definitive treatment. Do NOT delay for imaging
Aggressive IVF resuscitation, vasopressors for septic shock, ICU admission
Plan for re-look debridement in 24-48h (often need multiple OR trips, "second look")
Wound VAC after debridement stabilizes; delayed closure or skin grafting
Teaching point: "When in doubt, cut it out." Delay to debridement is the modifiable driver of mortality, and going past 24 hours raises it roughly 9-fold. CT and MRI can miss early disease, if clinical suspicion is high, the patient goes to the OR, not radiology.
📋 Case 2, Type II (Group A Strep) Necrotizing Fasciitis
Patient: 35F previously healthy. Severe left arm pain after minor cut while gardening 48h ago. Now with rapidly spreading purple discoloration, bullae. Temp 40.1°C, HR 135, BP 78/42. WBC 2.8K (leukopenia), platelets 68K. Blood cultures: GPC in chains.
Key findings: Type II = monomicrobial GAS (Streptococcus pyogenes). Can occur in healthy young adults. Streptococcal toxic shock syndrome (STSS): hypotension + organ failure + soft tissue infection. Leukopenia paradoxically indicates severe disease.
Management:
Emergent radical surgical debridement, may require amputation if limb-threatening
Penicillin G 4 million units IV q4h + clindamycin 900 mg IV q8h (clindamycin stops exotoxin production)
ICU: vasopressors, ventilator support, blood products for DIC
Notify public health, GAS necrotizing fasciitis is reportable in many jurisdictions
Teaching point: GAS necrotizing fasciitis can kill a healthy young adult in 24-48h. The clue is "pain out of proportion" + rapid systemic deterioration. IVIG is specifically beneficial for streptococcal toxic shock, it binds superantigens that drive the immune storm.
📋 Case 3, Fournier Gangrene
Patient: 58M with poorly controlled T2DM (A1c 11), presents with severe perineal pain, scrotal swelling, and foul-smelling discharge × 2 days. Temp 39.4°C, HR 130. Exam: scrotal erythema extending to perineum with crepitus. WBC 28K, lactate 4.8.
Key findings: Fournier gangrene = necrotizing fasciitis of the perineum/genitalia. Same pathophysiology as extremity necrotizing fasciitis. Diabetes is the #1 risk factor. Mortality 20-40% even with aggressive treatment.
Management:
Emergent surgical debridement of all necrotic tissue (urology + general surgery)
Same antibiotic regimen: vancomycin + piperacillin-tazobactam + clindamycin
Fecal diversion (colostomy) if perineal wound is extensive (prevents fecal contamination)
Suprapubic catheter if urethral involvement
Daily wound care, re-look in 24-48h, wound VAC once clean, delayed reconstruction
Teaching point: Fournier gangrene follows the same treatment principles as all necrotizing fasciitis: emergent surgical debridement is the ONLY life-saving intervention. Antibiotics without surgery = death. The threshold for surgical exploration should be very low.
Monitoring
Parameter
Frequency
Wound
q4–6h. Advancing necrosis = return to OR
Hemodynamics
Continuous ICU. MAP >65
CBC, CRP, lactate
q6–12h
Summary
Summary
The Hallmark Is the Mismatch
Pain out of proportion to the exam in a limb that looks deceptively unimpressive early. Later signs, skin necrosis, bullae, crepitus and anesthesia over the involved skin, mean the disease is already advanced. Systemic toxicity out of keeping with a cellulitis is the other tell.
Surgery Is the Treatment
Antibiotics do not cure necrotizing fasciitis; debridement does. Thrombosed perforating vessels mean the drug never reaches the dying fascia. Delay to debridement beyond 24 h carries roughly a 9-fold higher mortality, so surgical consultation happens at the moment of suspicion.
Do Not Wait for Imaging
Old teaching was CT or MRI first; current practice is straight to the operating room on clinical suspicion.CT can miss early disease, and a normal scan does not exclude it. If imaging is obtained it must not delay surgery.
The Bedside Test That Settles It
The finger test: a small incision under local anesthetic down to fascia. Tissue planes that separate with minimal resistance, dishwater-gray fluid and non-bleeding fascia are diagnostic. This is faster and more reliable than any scan.
Antibiotics: Broad, Plus a Toxin Blocker
Vancomycin 25 to 30 mg/kg load then 15 to 20 mg/kg q8-12h for MRSA, plus piperacillin-tazobactam 4.5 g IV q6h for gram-negatives and anaerobes, plus clindamycin 900 mg IV q8h. Narrow only after cultures and source control.
Why Clindamycin Is Not Optional
It is there for toxin suppression, not for coverage. Group A Strep and Clostridium drive shock through exotoxins, and clindamycin blocks their production by inhibiting protein synthesis. Beta-lactams do not suppress toxin, and they lose potency against a high-inoculum stationary-phase organism (the Eagle effect).
Know the Two Types and Gas Gangrene
Type 1 is polymicrobial, aerobes plus anaerobes, in diabetics, post-surgical and immunocompromised patients. Type 2 is monomicrobial Group A Strep in young healthy people after minor trauma. Gas gangrene is C. perfringens after trauma or surgical wounds. LRINEC can support the suspicion but a low score never rules it out.
Expect to Go Back
Plan a second look in 24 h and reassess the wound every 4 to 6 h. Advancing necrosis means a return to the operating room; most patients need several debridements. Support with ICU-level care, MAP above 65, and consider IVIG in streptococcal toxic shock.
HSV-1 and HSV-2 cause lifelong latent infections with episodic reactivation. Primary genital herpes is a clinical diagnosis, treat empirically, confirm with PCR. Acyclovir is the backbone of treatment. HSV encephalitis is a medical emergency requiring immediate IV acyclovir, do NOT wait for PCR results.
🔍 Overview
HSV-1 vs HSV-2
Feature
HSV-1
HSV-2
Primary site
Orolabial (cold sores), keratitis, encephalitis
Genital herpes (but HSV-1 now causes 50%+ of new genital herpes in young adults)
Latency
Trigeminal ganglia
Sacral ganglia (S2–S4)
Seroprevalence
~50–80% of adults
~12–16% of adults (higher in HIV+, MSM)
Reactivation frequency
Less frequent genitally; orolabial ∼1–3/year
More frequent genitally (avg 4–5/year in year 1, decreasing over time)
Transmission
Oral contact, saliva
Sexual contact; asymptomatic shedding drives most transmission
Clinical Syndromes
Syndrome
Presentation
Key Points
Primary genital herpes
Painful grouped vesicles on erythematous base → shallow ulcers. Bilateral. Inguinal lymphadenopathy. Dysuria. Systemic symptoms (fever, malaise, myalgias) common.
Worst episode, lasts 2–3 weeks untreated. Often confused with chancroid, syphilis, or contact dermatitis. Primary HSV-1 genital is increasingly common.
Recurrent genital herpes
Unilateral grouped vesicles, fewer lesions, shorter duration (5–10 days). Often preceded by prodrome (tingling, burning, itching).
Less severe than primary. HSV-2 recurs more often than HSV-1 genitally. Frequency decreases over years.
Orolabial herpes (cold sores)
Painful vesicles at vermilion border of lip. Prodrome of tingling 24h before.
Usually HSV-1. Treat with topical or oral antivirals if caught early (within 72h of onset).
OPHTHALMOLOGY EMERGENCY, can cause corneal scarring and blindness. Treat with topical ganciclovir or trifluridine. Do NOT give topical steroids (worsens viral keratitis).
Mortality 70% untreated. Start acyclovir 10 mg/kg IV q8h IMMEDIATELY if suspected, do NOT wait for CSF PCR. MRI: temporal lobe hyperintensity on T2/FLAIR. CSF: lymphocytic pleocytosis, elevated protein, RBCs.
Herpes whitlow
Painful vesicles on finger/thumb. Healthcare workers, thumb-sucking children.
Do NOT incise (not an abscess). Treat with oral acyclovir/valacyclovir. Self-limited in 2–3 weeks.
Eczema herpeticum
Widespread HSV over areas of eczema/atopic dermatitis. Punched-out erosions, fever.
Medical emergency in severe cases, IV acyclovir. Can be life-threatening in infants/immunocompromised.
Neonatal herpes
Skin/eye/mouth (SEM), CNS disease, or disseminated. Presents at 1–3 weeks of life.
Highest risk: primary maternal genital HSV near delivery. C-section if active lesions at labor. Mortality high if disseminated.
HSV encephalitis is the #1 treatable cause of fatal sporadic encephalitis. Temporal lobe involvement on MRI is classic. Start IV acyclovir BEFORE lumbar puncture results, delay increases mortality from 30% to 70%. Treat for 14–21 days minimum.
🧪 Workup
Diagnostic Testing
Test
When to Use
Key Points
HSV PCR (swab)
Active vesicles/ulcers, preferred test
Gold standard for genital/mucosal lesions. More sensitive than viral culture (3–5x). Swab base of unroofed vesicle. Can distinguish HSV-1 vs HSV-2.
HSV PCR (CSF)
Suspected HSV encephalitis or meningitis
Sensitivity 96–98%. Can be false-negative in first 72h, if high suspicion and initial PCR negative, repeat at 3–7 days. Do NOT stop acyclovir based on a single negative PCR early on.
Viral culture
Active vesicles (if PCR not available)
Sensitivity depends on lesion stage: highest in vesicles (> 90%), drops rapidly in crusted lesions (< 30%). Swab base of unroofed vesicle. Takes 2–5 days.
Type-specific serology (IgG)
No active lesions; screening; confirm past infection
HSV-1 IgG and HSV-2 IgG (glycoprotein G-based assays). Seroconversion takes 2–12 weeks after primary infection. IgM is NOT useful, cross-reacts, false positives, does not distinguish primary from recurrent. Do not order HSV IgM.
Tzanck smear
Bedside, rapid (if PCR unavailable)
Multinucleated giant cells = herpesvirus (HSV or VZV, cannot distinguish). Low sensitivity (60%). Largely replaced by PCR.
Do NOT order HSV IgM. It has poor sensitivity and specificity, cross-reacts between HSV-1 and HSV-2, cannot distinguish primary from recurrent infection, and frequently gives false-positive results causing unnecessary anxiety. Use type-specific IgG (glycoprotein G-based) instead.
HSV Encephalitis Workup
MRI brain with contrast, temporal lobe hyperintensity on T2/FLAIR (unilateral or bilateral) is classic. Sensitivity > 90%. CT misses early disease.
LP with CSF studies, HSV PCR, cell count (lymphocytic pleocytosis), protein (elevated), glucose (usually normal), RBCs (often present from hemorrhagic necrosis)
EEG, periodic lateralized epileptiform discharges (PLEDs) from temporal lobe. Helps if MRI equivocal.
Start acyclovir 10 mg/kg IV q8h BEFORE results, empiric treatment is the standard of care. Duration: 14–21 days.
🚨 Management
Treatment by Syndrome
Scenario
Treatment
Duration
Notes
Primary genital herpes
Valacyclovir (Valtrex) 1g PO BID or Acyclovir (Zovirax) 400 mg PO TID
7–10 days
Start as soon as possible (best within 72h of onset). Reduces duration by 3–5 days and viral shedding. Extend if lesions not healed at day 10.
Recurrent genital herpes (episodic)
Valacyclovir 500 mg PO BID × 3 days or Valacyclovir 1g PO daily × 5 days or Acyclovir 800 mg PO TID × 2 days
Valacyclovir 500 mg BID: 3 days Valacyclovir 1g daily: 5 days Acyclovir 800 mg TID: 2 days
Most effective if started during prodrome or within 24h of lesion onset. Patient-initiated therapy, prescribe in advance so patient can start at first sign.
Suppressive therapy
Valacyclovir 500 mg PO daily (if ≤9 episodes/yr) Valacyclovir 1g PO daily (if ≥10 episodes/yr)
Ongoing (reassess annually)
Reduces outbreaks by 70–80% and transmission to seronegative partners by ~50%. Recommend if: ≥6 episodes/year, severe episodes, serodiscordant couple, significant psychological impact.
Orolabial herpes
Valacyclovir 2g PO q12h × 1 day or topical penciclovir (Denavir) cream q2h × 4 days
Valacyclovir: 1 day Penciclovir cream: 4 days
Start at prodrome (tingling). Systemic therapy more effective than topical. Sunscreen on lips prevents UV-triggered recurrences.
HSV encephalitis EMERGENCY
Acyclovir 10 mg/kg IV q8h
14–21 days
Start empirically, do NOT wait for CSF PCR. Adjust for renal function (CrCl). Aggressive IV hydration to prevent acyclovir crystalluria/nephrotoxicity. Repeat CSF PCR near end of treatment to confirm clearance.
HSV in immunocompromised
Valacyclovir 1g PO BID (mild) Acyclovir 5–10 mg/kg IV q8h (severe)
7–14 days (or until lesions healed)
Higher doses, longer courses. Consider acyclovir resistance if lesions not improving after 10 days, send for resistance testing. Treat resistant HSV with foscarnet 40 mg/kg IV q8h.
Neonatal herpes
Acyclovir 20 mg/kg IV q8h
14 days (SEM) or 21 days (CNS/disseminated)
Neonatology/ID consult. High-dose acyclovir. Follow with suppressive oral acyclovir × 6 months after IV course.
Valacyclovir vs acyclovir: Valacyclovir is the prodrug of acyclovir with 3–5x better oral bioavailability (55% vs 15–20%). Allows less frequent dosing and equivalent efficacy. Use valacyclovir for oral therapy; reserve IV acyclovir for severe disease (encephalitis, disseminated, immunocompromised).
Pregnancy Considerations
Primary genital herpes near delivery (<6 weeks before) → highest risk of neonatal transmission (30–50%) → C-section recommended
Recurrent genital herpes at delivery → much lower transmission risk (1–3%) → C-section if active lesions present at onset of labor
Suppressive therapy from 36 weeks: Acyclovir 400 mg PO TID or Valacyclovir 500 mg PO BID starting at 36 weeks gestation to reduce outbreaks at delivery and avoid unnecessary C-sections ACOG, 2020
Acyclovir/valacyclovir are safe in pregnancy (Category B), extensive safety data with no increased risk of birth defects
💊 Medications
Antiviral Medications for HSV
Drug (Brand)
Mechanism
Dosing
Key Considerations
Acyclovir (Zovirax)
Nucleoside analog, activated by viral thymidine kinase → inhibits viral DNA polymerase
Poor oral bioavailability (15–20%). Nephrotoxic (crystalluria), aggressive IV hydration, dose-adjust for CrCl. IV formulation for severe disease only.
Valacyclovir (Valtrex)
Prodrug of acyclovir, converted to acyclovir in gut/liver. Same mechanism.
500 mg–2g PO, 1–2x daily (varies by indication)
Preferred oral agent, better bioavailability (55%) = less frequent dosing. Same efficacy as acyclovir. Dose-adjust for renal impairment. Rare: TTP/HUS at very high doses in immunocompromised.
Famciclovir (Famvir)
Prodrug of penciclovir, similar mechanism to acyclovir
250–500 mg PO BID-TID
Third-line option. Similar efficacy. No IV formulation. Use if intolerant to valacyclovir.
Foscarnet (Foscavir)
Directly inhibits viral DNA polymerase (no thymidine kinase activation needed)
40 mg/kg IV q8h
For acyclovir-resistant HSV (usually in immunocompromised). Highly nephrotoxic. Electrolyte wasting (Ca²⁺, Mg²⁺, K⁺). Painful genital ulcers as side effect. Monitor renal function and electrolytes closely.
Acyclovir resistance: Suspect if lesions not improving after 10 days of appropriate-dose acyclovir in immunocompromised patient. Caused by thymidine kinase mutations (most common). Treat with foscarnet (does not require TK activation). Send viral culture with resistance testing. Resistance is rare in immunocompetent patients.
📋 On Rounds
What is the most important step in managing suspected HSV encephalitis?
Start IV acyclovir 10 mg/kg q8h immediately, do NOT wait for CSF PCR results or MRI. Mortality is 70% untreated vs ~20% with early acyclovir. Every hour of delay worsens outcomes. Treat for 14–21 days. Temporal lobe involvement on MRI is classic but not required to initiate treatment.
Why should you never order HSV IgM?
HSV IgM has poor sensitivity and specificity, cross-reacts between HSV-1 and HSV-2, cannot distinguish primary from recurrent infection, and frequently gives false-positive results. It causes unnecessary anxiety and does not change management. Use type-specific IgG (glycoprotein G-based) for serologic diagnosis or HSV PCR swab for active lesions.
When do you recommend suppressive therapy for genital herpes?
Suppressive therapy (valacyclovir 500 mg–1g daily) is recommended for: (1) ≥6 recurrences per year, (2) serodiscordant couples (reduces transmission by ~50%), (3) severe episodes causing significant morbidity, (4) significant psychological impact. Also start at 36 weeks gestation in pregnant women with history of genital herpes to reduce outbreaks at delivery.
What is the difference between HSV-1 and HSV-2 genital herpes?
HSV-1 now causes >50% of new genital herpes in young adults (via oral-genital contact). HSV-1 genital herpes recurs less frequently (avg 1/year vs 4–5/year for HSV-2). HSV-2 genital herpes recurs more often and has more asymptomatic shedding. Both respond to the same antivirals. Type-specific serology (IgG) or PCR swab can distinguish them, important for counseling on recurrence risk and transmission.
What is herpes whitlow and why should you NOT incise it?
Herpes whitlow is HSV infection of the finger, typically in healthcare workers (from contact with oral/genital secretions) or children who suck their thumbs. It presents as painful vesicles on the distal finger. Do NOT incise, it mimics a felon (bacterial abscess) but is viral. Incision can spread virus, cause secondary bacterial infection, and delay healing. Treat with oral antivirals (valacyclovir). Self-limited in 2–3 weeks.
📣 Sample Presentation
One-Liner
"Ms. Chen is a 24-year-old woman presenting with her first episode of painful genital vesicles and ulcers × 4 days, with inguinal lymphadenopathy and low-grade fever, consistent with primary genital herpes."
Key Points to Cover on Rounds
Primary genital herpes, clinical diagnosis with grouped vesicles on erythematous base. Sent HSV PCR swab for type-specific confirmation. Started valacyclovir 1g PO BID × 10 days. Counseling provided: lifelong infection, asymptomatic shedding, condom use, disclosure to partners, suppressive therapy options if frequent recurrences. Screened for other STIs (HIV, syphilis, gonorrhea, chlamydia). Not pregnant, no delivery planning needed. Follow-up with PCP for ongoing management.
⚡ Summary
Summary
Start Acyclovir Before the LP Result
HSV encephalitis is the leading treatable cause of fatal sporadic encephalitis.Delay raises mortality from about 30% to 70%, so IV acyclovir 10 mg/kg q8h goes in on suspicion, before the lumbar puncture is done and long before the PCR returns. Treat for 14 to 21 days.
Recognize the Encephalitis Picture
Fever, altered mental status, seizures and personality or behavioral change, with temporal lobe involvement on MRI.CSF shows a lymphocytic pleocytosis with red cells from the hemorrhagic necrosis, and PCR is the diagnostic test. A negative PCR in the first 72 h can be falsely negative, so repeat it rather than stopping treatment on one result.
Do Not Order HSV IgM
Poor sensitivity and specificity, cross-reacts between HSV-1 and HSV-2, cannot distinguish primary from recurrent infection, and produces false positives that cause real distress.Use PCR of a lesion swab or CSF, and type-specific IgG only when the question is whether someone has ever been infected.
Use Valacyclovir Orally and Acyclovir Intravenously
Valacyclovir is the prodrug with 3 to 5 times better oral bioavailability (55% vs 15 to 20%), allowing less frequent dosing at equivalent efficacy. Reserve IV acyclovir for severe or disseminated disease, encephalitis, neonatal infection and the immunocompromised.Hydrate with IV acyclovir, which crystallizes in the tubules and causes acute kidney injury.
Treat Early and Match the Syndrome
Antivirals shorten the episode but do not eradicate latent virus, so they work best started within 72 h of a primary outbreak or at the first prodromal symptom of a recurrence. Primary genital herpes needs 7 to 10 days; recurrences need 1 to 5 days; suppressive therapy is for frequent recurrences and reduces transmission to partners.
Do Not Miss Ocular and Whitlow Disease
HSV keratitis presents with a dendritic ulcer on fluorescein staining and needs same-day ophthalmology, and topical steroids without antiviral cover can cause corneal perforation and blindness. Herpetic whitlow is a painful finger infection acquired occupationally, and it is managed medically: incising it makes it worse.
Pregnancy Changes the Delivery Plan
Cesarean delivery for active genital lesions or prodromal symptoms at labor, since neonatal HSV carries high mortality and neurologic morbidity. Suppressive valacyclovir from 36 weeks in women with recurrent genital herpes reduces outbreaks and the need for cesarean. A primary infection acquired near term carries the highest transmission risk, because there are no maternal antibodies to transfer.
Suspect Resistance When It Will Not Heal
Lesions not improving after 10 days of correctly dosed acyclovir in an immunocompromised patient.Thymidine kinase mutations are the usual mechanism, which means the whole acyclovir family fails. Treat with foscarnet, which does not require TK activation, monitoring renal function and electrolytes, particularly calcium.
Syphilis rates are surging, cases have tripled since 2018. The "great imitator" mimics nearly anything. Penicillin G is the ONLY proven treatment. Screen all HIV patients, pregnant women, and MSM. Congenital syphilis is preventable with prenatal screening.
🔍 Overview
Stages of Syphilis
Stage
Timing
Presentation
Key Features
Primary
10–90 days post-exposure (avg 21 days)
Painless chancre, single, firm, round ulcer with clean base and raised borders at site of inoculation (genital, anal, oral).
Painless + non-tender lymphadenopathy. Heals spontaneously in 3–6 weeks even without treatment. Highly infectious. Often missed (painless, internal location).
Secondary
4–10 weeks after chancre
Diffuse maculopapular rash including palms and soles (classic). Condylomata lata (moist, flat, gray lesions in intertriginous areas). Mucous patches. Patchy alopecia ("moth-eaten").
Constitutional symptoms: fever, malaise, weight loss, diffuse lymphadenopathy. Highest spirochete burden = most infectious stage. Resolves in weeks–months even untreated.
Latent (early)
< 1 year since infection
Asymptomatic. Positive serology only.
Still infectious (sexual + vertical transmission). Diagnosed by positive serology without symptoms. May relapse to secondary syphilis.
Latent (late)
> 1 year since infection (or unknown duration)
Asymptomatic. Positive serology only.
Low infectivity. Not sexually transmitted at this stage. Important for treatment duration (requires 3 weekly IM penicillin doses vs 1).
Tertiary
Years–decades after infection
Gummatous (destructive granulomas of skin, bone, organs). Cardiovascular (aortitis, ascending aortic aneurysm). Late neurologic.
Rare in antibiotic era. Aortitis with "tree-bark" calcification of ascending aorta is classic. Gummas are non-infectious. Treat with penicillin.
Neurosyphilis CAN OCCUR AT ANY STAGE
Early (meningitis, CN palsies, ocular, otic) or late (tabes dorsalis, general paresis)
Argyll Robertson pupils = accommodate but do not react (to light). "Prostitute's pupils", accommodate but don't react. LP for CSF VDRL. Treat with IV penicillin G × 10–14 days.
Syphilis is the "great imitator." Secondary syphilis can mimic: pityriasis rosea, drug eruption, psoriasis, viral exanthem, SLE, Rocky Mountain spotted fever. Key clue: rash involving palms and soles in a sexually active patient = syphilis until proven otherwise. Always screen for HIV concurrently.
🧪 Workup
Diagnostic Algorithm
Test
What It Detects
Key Points
RPR or VDRL (Non-treponemal)
Antibodies to cardiolipin released by damaged cells
Screening test. Quantitative titer correlates with disease activity. Use to follow treatment response (expect 4-fold decline by 6–12 months). False positives: pregnancy, lupus, antiphospholipid syndrome, endocarditis, hepatitis, aging.
FTA-ABS or TP-PA (Treponemal)
Antibodies to T. pallidum antigens
Confirmatory test. Once positive, stays positive for life (even after treatment), cannot be used to follow treatment response. More specific than RPR/VDRL.
Reverse screening (increasingly used)
Treponemal test first (EIA/CIA), then RPR
Many labs now use automated treponemal EIA as first step. If EIA positive + RPR negative → get TP-PA to confirm. Can detect early primary syphilis before RPR turns positive.
Darkfield microscopy
Direct visualization of spirochetes
Gold standard for primary chancre (before serology turns positive). Rarely available. Operator-dependent.
CSF VDRL
Neurosyphilis
Highly specific but insensitive (30–70%). A positive CSF VDRL confirms neurosyphilis. A negative CSF VDRL does NOT rule it out. Also check CSF cell count, protein, and CSF FTA-ABS (sensitive but less specific).
When to do LP for neurosyphilis: (1) Neurologic or ophthalmologic symptoms at any stage, (2) Treatment failure (titer not declining), (3) HIV + late latent syphilis, (4) Tertiary syphilis. Ocular syphilis (uveitis, optic neuritis) and otosyphilis (hearing loss) are always treated as neurosyphilis with IV penicillin, even if LP is normal.
Screening Recommendations
All pregnant women, at first prenatal visit, repeat at 28 weeks and delivery in high-risk populations
All HIV-positive patients, at diagnosis and annually (more often if high-risk behavior)
MSM, at least annually; every 3–6 months if multiple partners or high-risk behavior
Anyone diagnosed with another STI (gonorrhea, chlamydia, HIV)
Incarcerated populations, commercial sex workers
🚨 Management
Treatment by Stage
Stage
Treatment
PCN Allergy
Follow-Up
Primary, Secondary, Early Latent (<1 year)
Benzathine penicillin G (Bicillin L-A) 2.4 million units IM × 1 dose
Doxycycline 100 mg PO BID × 14 days
RPR at 6 and 12 months. Expect 4-fold decline by 6–12 months. If not declining → retreat or evaluate for neurosyphilis.
Late Latent, Unknown Duration, Tertiary (non-neuro)
Benzathine penicillin G 2.4 million units IM weekly × 3 doses
Doxycycline 100 mg PO BID × 28 days
RPR at 6, 12, and 24 months. Slower decline expected. Missing a dose → restart series if >14 days late.
Neurosyphilis (including ocular and otic) IV REQUIRED
Aqueous crystalline penicillin G 18–24 million units/day IV (3–4 million q4h) × 10–14 days
Desensitize to penicillin (no reliable alternative for neurosyphilis). Ceftriaxone 2g IV daily × 10–14d is a second-line option.
Repeat LP at 6 months. CSF pleocytosis should normalize. If not improving → retreat.
Jarisch-Herxheimer reaction: Occurs in 10–35% of patients within 24h of first penicillin dose (most common in secondary syphilis). Fever, rigors, myalgia, headache, tachycardia, transient rash flare. Caused by cytokine release from spirochete lysis. Self-limited. Treat with NSAIDs/antipyretics. Warn patients in advance. In pregnancy, can trigger contractions/fetal distress, monitor closely.
🔄 Updated Practice: Penicillin is the ONLY proven treatment for neurosyphilis and syphilis in pregnancy. For PCN-allergic pregnant patients, desensitize to penicillin (protocol takes ~4 hours in monitored setting). Doxycycline is contraindicated in pregnancy. Azithromycin resistance is emerging, no longer recommended as alternative.
💊 Medications
Key Medications
Drug (Brand)
Dose / Route
Key Notes
Benzathine penicillin G (Bicillin L-A)
2.4 million units IM (gluteal)
Drug of choice for all stages (except neurosyphilis). Long-acting depot provides sustained treponemicidal levels. Do NOT confuse with Bicillin C-R (combination product, wrong formulation). Painful injection, can mix with 1% lidocaine.
Aqueous crystalline penicillin G
3–4 million units IV q4h
For neurosyphilis, ocular syphilis, otic syphilis. Achieves adequate CSF levels (benzathine does NOT). 10–14 days. Requires IV access.
Doxycycline
100 mg PO BID
Alternative for non-pregnant PCN-allergic patients. 14 days (early) or 28 days (late). NOT adequate for neurosyphilis. Contraindicated in pregnancy.
Ceftriaxone
1–2g IV/IM daily
Limited data. May be used for neurosyphilis in PCN allergy if desensitization not possible (cross-reactivity <2%). Not first-line.
📋 On Rounds
A patient has a positive RPR (1:64) and positive FTA-ABS. What stage and how do you treat?
High RPR titer (1:64) with positive confirmatory FTA-ABS = active syphilis. Determine stage by history and exam: if primary/secondary/early latent (<1 year) → benzathine penicillin G 2.4 MU IM × 1 dose. If late latent or unknown duration → 3 weekly IM doses. If neurologic symptoms → LP and IV penicillin. Follow RPR at 6 and 12 months, expect 4-fold decline. Always test for HIV concurrently.
What are Argyll Robertson pupils and what do they indicate?
Argyll Robertson pupils accommodate (constrict to near focus) but do NOT react to light. They are small, irregular, and bilateral. Classic for neurosyphilis (tabes dorsalis). Mnemonic: "Prostitute's pupils", they accommodate but don't react. The lesion is in the pretectal area of the midbrain disrupting the pupillary light reflex while sparing the accommodation pathway.
What rash involves the palms and soles?
The differential for rash on palms and soles: Secondary syphilis (#1 to rule out in a sexually active adult), Rocky Mountain spotted fever (tick exposure, starts on wrists/ankles, spreads centripetally), hand-foot-mouth disease (coxsackievirus, children), endocarditis (Janeway lesions, painless), reactive arthritis (keratoderma blennorrhagicum), psoriasis (palmoplantar). In a sexually active patient, always rule out syphilis first with RPR.
Why is penicillin the ONLY option for neurosyphilis and syphilis in pregnancy?
Neurosyphilis: Only IV penicillin G achieves reliable treponemicidal CSF concentrations. Benzathine penicillin does not cross the blood-brain barrier adequately. Doxycycline and ceftriaxone have limited CNS data. Pregnancy: Penicillin is the only agent proven to treat the fetus and prevent congenital syphilis. Doxycycline is contraindicated (tooth/bone effects). Azithromycin has emerging resistance and doesn't cross placenta reliably. If PCN-allergic and pregnant → penicillin desensitization is mandatory.
📣 Sample Presentation
One-Liner
"Mr. Jackson is a 32-year-old MSM presenting with diffuse maculopapular rash including palms and soles, oral mucous patches, and low-grade fever × 2 weeks, with RPR 1:128 and positive FTA-ABS, consistent with secondary syphilis."
Key Points to Cover on Rounds
Secondary syphilis, confirmed by high-titer RPR (1:128) + positive FTA-ABS + classic rash. Treated with benzathine penicillin G 2.4 MU IM × 1 dose. Counseled on Jarisch-Herxheimer reaction (fever/myalgias within 24h, self-limited). HIV test sent (negative). Sexual partners within 90 days need testing and empiric treatment. RPR follow-up at 6 and 12 months, expect 4-fold titer decline. Reported to public health department.
⚡ Summary
Summary
Stage It, Because Stage Sets the Treatment
Primary: a painless chancre 10 to 90 days after exposure that heals on its own.Secondary: weeks to months later, with a diffuse rash including palms and soles, condylomata lata, mucous patches and systemic symptoms.Latent: asymptomatic, early (under 1 year) or late.Tertiary: gummas, cardiovascular and neurologic disease years later.
The Great Imitator
Secondary syphilis mimics pityriasis rosea, drug eruption, psoriasis, viral exanthem, lupus and Rocky Mountain spotted fever.The clue is a rash involving the palms and soles in a sexually active patient, which very few other conditions produce. Test for it whenever that rash appears, because the chancre is painless and is routinely missed or never seen.
Understand What the Two Test Types Do
Non-treponemal tests (RPR, VDRL) are quantitative and used to follow response, and they eventually become negative after treatment.Treponemal tests (FTA-ABS, TP-PA, EIA) confirm and stay positive for life, so they can never distinguish current from treated past infection. The reverse sequence algorithm screens with a treponemal test first, then confirms with RPR, then a second treponemal test to settle discordant results.
Know the Two Ways the Serology Fools You
The prozone phenomenon: a very high antibody titer, typically in secondary syphilis or HIV, produces a falsely negative RPR until the sample is diluted, so ask the lab to dilute when the clinical picture is convincing. Biologic false positives on non-treponemal tests occur in pregnancy, autoimmune disease, older age and other infections, which is what the confirmatory treponemal test exists to sort out.
Treat by Stage With Penicillin
Primary, secondary and early latent: benzathine penicillin G 2.4 million units IM once.Late latent, unknown duration and tertiary: 2.4 million units IM weekly for 3 weeks.Neurosyphilis and ocular or otic syphilis: aqueous crystalline penicillin G 18 to 24 million units daily IV for 10 to 14 days.Benzathine penicillin does not reach the CNS, which is why the neurosyphilis regimen is completely different.
Penicillin Is Non-Negotiable in Two Groups
Pregnancy and neurosyphilis have no proven alternative.A penicillin-allergic pregnant patient is desensitized, a roughly 4-hour protocol in a monitored setting, and then treated. Doxycycline is contraindicated in pregnancy and does not treat the fetus; it is an option only for non-pregnant penicillin-allergic patients with early or late latent disease.
Know When to Tap
LP for neurologic or ophthalmologic symptoms at any stage, for treatment failure with a titer that will not fall, for HIV with late latent syphilis, and for tertiary disease.Ocular syphilis is treated as neurosyphilis regardless of the CSF result, and it needs same-day ophthalmology because untreated it blinds.
Warn About Jarisch-Herxheimer and Follow the Titer
Fever, rigors, myalgia, headache and a transient rash flare within 24 h of the first penicillin dose, in 10 to 35% of patients, most often in secondary syphilis. It is cytokine release from dying spirochetes, not an allergy, so treat with antipyretics and do not stop the penicillin. Warn pregnant patients specifically, since it can precipitate contractions and fetal distress. Follow RPR at 6 and 12 months, expecting a fourfold fall, test for HIV and other STIs, and treat the partners.
VZV reactivation from dorsal root ganglia causes painful dermatomal vesicles. Treat within 72h of rash onset with valacyclovir to reduce severity and postherpetic neuralgia risk. Ophthalmology emergency if V1 (forehead/eye) involved. Shingrix vaccine is >90% effective and recommended for all adults ≥50.
🔍 Overview
Herpes Zoster, Key Concepts
Reactivation of VZV from dorsal root ganglia (latent since primary varicella/chickenpox infection)
Dermatomal distribution, unilateral, does NOT cross midline (except in immunocompromised with disseminated disease)
Most common dermatomes: T3–L3 (thoracic > lumbar > cervical). Can affect any dermatome including cranial nerves.
Lifetime risk: ~30% of all adults will develop shingles; increases with age
Infectious: vesicular fluid contains live VZV, can cause primary varicella (chickenpox) in non-immune contacts. Airborne + contact precautions until lesions crusted.
Clinical Syndromes & Complications
Syndrome
Presentation
Key Points
Classic dermatomal zoster
Prodrome of pain/burning/tingling 2–3 days before rash. Then grouped vesicles on erythematous base in a single dermatome, unilateral. Pain is often severe, burning, stabbing, lancinating.
Clinical diagnosis in most cases. Rash evolves: papules → vesicles → pustules → crusting over 7–10 days. Pain may precede rash by days (can be confused with MI, pleurisy, renal colic).
Herpes zoster ophthalmicus (HZO) EMERGENCY
V1 (ophthalmic division of trigeminal) involvement. Vesicles on forehead, eyelid, nose.
Hutchinson sign = vesicles on tip/side of nose (nasociliary nerve) → 76% risk of ocular involvement. Urgent ophthalmology consult. Can cause keratitis, uveitis, retinal necrosis, blindness.
Ramsay Hunt syndrome
VZV reactivation in geniculate ganglion (CN VII). Vesicles in ear canal/pinna + ipsilateral facial paralysis + hearing loss/vertigo.
Triad: ear vesicles + facial palsy + CN VIII symptoms. Worse prognosis than Bell’s palsy for recovery. Treat with valacyclovir + prednisone.
Postherpetic neuralgia (PHN)
Pain persisting >90 days after rash onset. Burning, allodynia (pain from light touch), lancinating.
Most common complication. Risk increases with age (>60 years), severity of acute pain, and extent of rash. Antivirals within 72h reduce PHN risk. Treatment: gabapentin, pregabalin, duloxetine, lidocaine patch, capsaicin.
Disseminated zoster
>20 vesicles outside the primary + adjacent dermatomes. Looks like varicella.
Occurs in immunocompromised (HIV, transplant, chemo). Treat with IV acyclovir. Can involve lungs, liver, CNS. Airborne + contact precautions.
Risk of stroke is 1.3x higher for 1 year after zoster. Consider in unexplained stroke after recent shingles. Treat with IV acyclovir.
Hutchinson sign = ophthalmology emergency. Vesicles on the tip or side of the nose indicate nasociliary nerve involvement (V1) and predict ocular complications in 76% of cases. Get urgent ophthalmology consult even if the eye looks normal, keratitis/uveitis can develop over days.
🧪 Workup
Diagnosis
Clinical diagnosis in most cases, unilateral dermatomal vesicular rash is classic. Lab confirmation rarely needed.
VZV PCR (swab of unroofed vesicle), gold standard when diagnosis is uncertain. Highly sensitive and specific. Also useful for disseminated zoster, atypical presentations, and immunocompromised patients.
DFA (direct fluorescent antibody), rapid but less sensitive than PCR. Can distinguish VZV from HSV.
Tzanck smear, multinucleated giant cells (same as HSV, cannot distinguish). Low sensitivity. Largely replaced by PCR.
When to confirm with lab testing: atypical presentations (no vesicles, unusual location, immunocompromised), disseminated disease, CNS involvement, zoster sine herpete (dermatomal pain without rash, diagnosed by VZV PCR of skin swab or CSF).
🚨 Management
Treatment
Scenario
Treatment
Duration
Notes
Uncomplicated zoster
Valacyclovir (Valtrex) 1g PO TID
7 days
Start within 72h of rash onset for best efficacy. Reduces pain duration, rash healing time, and PHN risk. Can still start after 72h if: new vesicles still forming, immunocompromised, or HZO.
HZO (ophthalmic zoster) URGENT
Valacyclovir 1g PO TID + ophthalmology consult
7–10 days
Start antivirals regardless of timing. Ophthalmology for slit-lamp exam, IOP check, fundoscopy. May need topical steroids + cycloplegics if uveitis.
Ramsay Hunt
Valacyclovir 1g PO TID + prednisone 60 mg PO daily × 5 days then taper
7 days antivirals
Combined antiviral + steroid improves facial nerve recovery. ENT referral. Worse prognosis than Bell’s palsy for complete recovery.
Disseminated / Immunocompromised
Acyclovir 10 mg/kg IV q8h
7–10 days (until no new lesions × 48h)
IV therapy for disseminated disease, CNS involvement, or severe immunosuppression. Transition to PO valacyclovir when improving and able to take PO.
Pain Management
Phase
Medications
Notes
Acute zoster pain
Acetaminophen + NSAIDs (first-line). Gabapentin 300–1200 mg TID for neuropathic component. Short-course opioids if severe.
Pain can be intense, don’t undertreat. Start gabapentin early to reduce risk of PHN transition.
Postherpetic neuralgia (PHN)
Gabapentin (Neurontin) 300–3600 mg/day Pregabalin (Lyrica) 75–300 mg BID Duloxetine (Cymbalta) 60 mg daily Lidocaine 5% patch (topical, up to 3 patches/12h) Capsaicin 8% patch (applied in clinic)
First-line: gabapentin or pregabalin. Lidocaine patch for localized pain. TCAs (amitriptyline 25–75 mg QHS) are effective but limited by side effects in elderly. Opioids are last resort.
>90% effective at preventing shingles and PHN across all age groups ZOE-50, 2015
Recommended for all adults ≥50 regardless of prior shingles episode or prior Zostavax (old live vaccine)
Also recommended for immunocompromised adults ≥19 (transplant, HIV, autoimmune on immunosuppression), Shingrix is non-live and safe
Common side effects: injection site pain (78%), myalgia, fatigue, self-limited 1–3 days
Shingrix replaced Zostavax. Zostavax (live attenuated) was only ~51% effective and waned significantly after 5 years. Shingrix maintains >85% efficacy at 4+ years. Shingrix is safe in immunocompromised (non-live vaccine). No need to check varicella history before vaccinating, >99% of adults ≥50 are VZV seropositive.
2 doses, 0.5 mL IM (deltoid). Dose 1 at day 0, Dose 2 at 2-6 months later
Who
All adults ≥ 50 years (immunocompetent). Immunocompromised adults ≥ 19 years (HIV, transplant, chemo, biologics, chronic steroids)
Efficacy
97% effective in adults 50-69; 91% effective in adults ≥ 70 ZOE-50, 2015ZOE-70, 2016
Duration of protection
>85% efficacy maintained at 4+ years. Long-term data still accumulating.
Common side effects
Injection site pain (78%), myalgia (45%), fatigue (45%), headache (38%), shivering (27%), fever (21%), GI symptoms (17%). Self-limited 1-3 days. Warn patients, reactogenicity is high but normal.
Missed dose 2?
If >6 months since dose 1, give dose 2 as soon as possible. Do NOT restart the series, any interval is acceptable.
Coadministration
Can be given with other vaccines (flu, pneumococcal, Tdap, COVID-19) at different injection sites. No minimum interval required.
When to Vaccinate vs. Defer
Scenario
Vaccinate?
Notes
Active zoster (open vesicular lesions)
DEFER
Wait until acute episode resolves and lesions have fully crusted. Vaccinating during active disease offers no benefit and may confuse clinical picture. Typically wait 2-3 months after episode to vaccinate.
Recent zoster (crusted, healing)
WAIT
Wait until rash has fully resolved. No minimum interval required after resolution, but most experts suggest 2-3 months to allow immune reconstitution and ensure the episode is truly over.
History of prior shingles (remote)
YES
Shingles can recur. Prior episode is NOT a contraindication. Vaccinate to prevent future episodes.
Prior Zostavax
YES
Shingrix is recommended regardless of prior Zostavax. Wait at least 2 months after Zostavax before giving Shingrix.
Shingrix is non-live and safe. Recommended for immunocompromised adults ≥ 19 years. Ideally vaccinate during periods of disease stability or low-intensity immunosuppression. May have reduced efficacy.
Pregnancy
DEFER
Insufficient safety data. Defer until postpartum.
Moderate-severe acute illness
WAIT
Defer until recovered. Minor illness (e.g., mild URI) is NOT a reason to delay.
Known allergy to vaccine component
CONTRAINDICATED
Anaphylaxis to a prior dose or known allergy to any component (e.g., polysorbate 80). This is the only true contraindication.
Open lesions = defer vaccination. Vesicular fluid contains live VZV and the patient is actively infectious. Vaccinating during active zoster does not treat the current episode (Shingrix is preventive, not therapeutic). Wait for full crusting, then vaccinate 2-3 months later to prevent recurrence. Meanwhile, ensure contact precautions until all lesions are crusted.
💊 Medications
Key Medications for Herpes Zoster
Drug (Brand)
Dose
Key Notes
Valacyclovir (Valtrex)
1g PO TID × 7 days
Preferred oral agent. Better bioavailability than acyclovir = more convenient dosing (TID vs 5x/day). Same efficacy. Dose-adjust for renal impairment.
Acyclovir (Zovirax)
Oral: 800 mg PO 5x/day × 7 days IV: 10 mg/kg q8h
Oral has poor bioavailability (requires 5x daily dosing, less convenient than valacyclovir). IV for disseminated disease, immunocompromised, CNS involvement. Hydrate aggressively to prevent nephrotoxicity.
Famciclovir (Famvir)
500 mg PO TID × 7 days
Alternative to valacyclovir. Similar efficacy. Use if intolerant to valacyclovir.
Gabapentin (Neurontin)
300–1200 mg PO TID
First-line for neuropathic pain (acute and PHN). Titrate slowly (start 300 mg QHS, increase every 3 days). Dose-adjust for renal function. Sedation, dizziness common initially.
Pregabalin (Lyrica)
75–150 mg PO BID
Alternative to gabapentin for PHN. Faster onset. More predictable pharmacokinetics. Schedule V controlled substance.
📋 On Rounds
What is the Hutchinson sign and why is it important?
Hutchinson sign = vesicles on the tip or side of the nose during herpes zoster. It indicates involvement of the nasociliary branch of V1 (ophthalmic division of trigeminal nerve), which also innervates the cornea and uvea. Positive Hutchinson sign predicts 76% risk of ocular complications (keratitis, uveitis, retinal necrosis). Requires urgent ophthalmology consult regardless of current eye symptoms.
When can you still start antivirals after 72 hours?
While antivirals are most effective within 72h of rash onset, you should still treat beyond 72h if: (1) New vesicles are still forming (active viral replication), (2) Immunocompromised patient (higher risk of dissemination and complications), (3) HZO (ophthalmic zoster) (risk of blindness justifies treatment at any time), (4) Ramsay Hunt (facial nerve at risk), (5) Disseminated zoster. The 72h window is a guideline, not an absolute cutoff.
How does Ramsay Hunt syndrome differ from Bell's palsy?
Ramsay Hunt = VZV reactivation in the geniculate ganglion causing the triad: (1) ear vesicles (external ear canal, pinna), (2) ipsilateral facial paralysis (LMN CN VII), (3) hearing loss or vertigo (CN VIII involvement). Bell's palsy = idiopathic (likely HSV-1-related) CN VII palsy without vesicles or hearing loss. Key differences: Ramsay Hunt has worse prognosis for recovery (complete recovery ~50% vs ~85% for Bell's), is treated with antiviral + steroid (vs steroid only for Bell's), and has visible vesicles in the ear.
What isolation precautions are needed for a hospitalized patient with shingles?
Localized zoster: Contact precautions + cover the lesions. Infectious until all vesicles are crusted. Keep away from immunocompromised patients, pregnant women (if non-immune), and neonates. Disseminated zoster: Airborne + contact precautions (VZV can spread via aerosol from disseminated lesions). The virus in vesicular fluid can cause primary varicella (chickenpox) in non-immune contacts, it does NOT cause shingles in others.
📣 Sample Presentation
One-Liner
"Mrs. Thompson is a 72-year-old woman presenting with 3 days of painful unilateral vesicular rash in a T6 dermatomal distribution, consistent with herpes zoster."
Key Points to Cover on Rounds
Herpes zoster, T6 dermatome, unilateral, does not cross midline. Onset 3 days ago with prodromal burning followed by vesicular eruption. Started valacyclovir 1g PO TID × 7 days (within 72h window). Pain management: acetaminophen + gabapentin 300 mg TID (titrating). No V1 involvement (no Hutchinson sign, no eye symptoms). Not immunocompromised, oral antivirals sufficient. Contact precautions until crusted. Shingrix vaccine after acute episode resolves (2–3 months). Monitoring for PHN development.
⚡ Summary
Summary
Recognize the Pattern
A painful vesicular rash in a single dermatome that does not cross the midline, from reactivation of latent varicella-zoster in a dorsal root ganglion. Pain frequently precedes the rash by days, so dermatomal pain with no visible cause is often the first presentation and gets attributed to something else.
Antivirals Work Best Inside 72 Hours
Valacyclovir 1 g TID for 7 days, or famciclovir, or acyclovir. Start within 72 h of rash onset, and still treat later if new vesicles are appearing, in ocular involvement, or in the immunocompromised. Antivirals shorten the acute illness and reduce postherpetic neuralgia; they do not eliminate the risk.
Hutchinson Sign Is an Ophthalmology Emergency
Vesicles on the tip or side of the nose mean nasociliary (V1) involvement and predict ocular complications in about 76% of cases.Get an urgent ophthalmology consult even when the eye looks normal, because herpes zoster ophthalmicus causes keratitis, uveitis and vision loss that is preventable if treated early.
Know the Other Named Syndromes
Ramsay Hunt syndrome: facial palsy with vesicles in the ear canal, often with hearing loss and vertigo, treated with an antiviral plus steroids and carrying a worse recovery than Bell palsy. Disseminated zoster, more than 20 lesions outside the dermatome or visceral involvement, needs IV acyclovir and airborne plus contact isolation. Zoster sine herpete, dermatomal pain with no rash, diagnosed by VZV PCR.
Treat the Pain Properly From the Start
Acute pain is often severe and under-treated. Use scheduled analgesia, adding gabapentin or pregabalin, a tricyclic, or topical lidocaine. Aggressive early pain control may reduce the risk of postherpetic neuralgia, so this is not simply comfort care.
Postherpetic Neuralgia Is the Main Morbidity
Pain persisting beyond 90 days, and the risk rises steeply with age.Treat with gabapentinoids, tricyclics, topical lidocaine or capsaicin, titrating to effect over weeks. Opioids are a poor long-term answer for what is neuropathic pain.
Isolation Depends on the Form
Localized zoster in an immunocompetent patient: contact precautions and cover the lesions.Disseminated zoster, or any zoster in an immunocompromised patient: airborne plus contact precautions.The fluid in the vesicles transmits varicella, not zoster, so a susceptible contact develops chickenpox, which matters for pregnant staff and immunocompromised patients on the ward.
Vaccinate With Shingrix
Two doses, and it replaced Zostavax.Zostavax was live attenuated, only about 51% effective and waned within 5 years; Shingrix maintains above 85% efficacy at 4 years and, being non-live, is safe in the immunocompromised. Vaccinate even after an episode of shingles, since recurrence occurs, and defer only until the acute episode has resolved.
Septic arthritis is a joint emergency, delay in drainage and antibiotics leads to irreversible cartilage destruction within 24–48 hours. The knee is the most commonly affected joint. Synovial fluid WBC >50,000 with >90% PMNs is the diagnostic hallmark. Aspirate before antibiotics when possible, but never delay empiric treatment for a toxic-appearing patient.
🔍 Overview
Key Concepts
Definition: Bacterial infection within a joint space, a true orthopedic/medical emergency requiring urgent drainage and IV antibiotics
Incidence: 2–10 per 100,000/year; higher in RA, prosthetic joints, immunosuppression, IV drug use
Most common joint: Knee (50%), followed by hip, shoulder, ankle, wrist
Route: Hematogenous spread (most common), direct inoculation (trauma, injection, surgery), contiguous spread from adjacent osteomyelitis
Irreversible cartilage damage begins within 24–48 hours if untreated, this is why urgent drainage is essential
Most common cause in sexually active young adults. Migratory polyarthralgia → mono/oligoarthritis + tenosynovitis + skin lesions (pustular). Blood/synovial cultures often negative, send NAAT.
Children <5 years
S. aureus, Kingella kingae, Group A Strep
Kingella often culture-negative, request PCR/16S rRNA. H. influenzae now rare (vaccination).
Septic arthritis and crystal arthropathy can coexist. Finding crystals on synovial fluid does NOT rule out infection. If clinical suspicion is high, treat empirically until cultures finalize, gout and septic arthritis overlap in 5% of cases.
🧪 Workup
Synovial Fluid Analysis, The Key Diagnostic Test
Arthrocentesis is mandatory for any acute monoarthritis with effusion. Aspirate BEFORE starting antibiotics when possible (but do not delay antibiotics if patient is septic).
Parameter
Normal
Non-inflammatory
Inflammatory (Gout/RA)
Septic
Appearance
Clear, colorless
Clear, yellow
Translucent–opaque, yellow
Opaque, purulent
WBC (/μL)
<200
200–2,000
2,000–50,000
>50,000 (often >100K)
PMN %
<25%
<25%
50–70%
>90%
Gram stain
Negative
Negative
Negative
Positive in 50–75%
Culture
Negative
Negative
Negative
Positive in 70–90%
Crystals
None
None
MSU (gout) or CPPD
Usually none (but coexistence possible)
WBC >50,000 with >90% PMNs = septic until proven otherwise. However, partially-treated infections and prosthetic joint infections may have lower WBC counts. A WBC of 25,000–50,000 does NOT rule out infection, clinical context matters.
Additional Workup
Test
Rationale
Synovial fluid Gram stain & culture
Gold standard. Positive in ~70–90% for non-gonococcal. Only ~25% positive for gonococcal. Send in blood culture bottles to improve yield.
Synovial fluid crystal analysis
Rule out gout (negatively birefringent MSU) and pseudogout (weakly positive CPPD). Remember: crystals + infection can coexist.
Blood cultures (×2 sets)
Positive in 40–50% of non-gonococcal septic arthritis. Essential for tailoring therapy.
CBC, CRP, ESR
WBC, CRP elevated in most cases. CRP >100 mg/L has high sensitivity. ESR less specific. Useful for monitoring treatment response.
Often normal early. Soft tissue swelling, joint effusion. Late: joint space narrowing, erosions, periosteal reaction. Baseline for comparison.
Ultrasound
Detect effusion (especially hip, difficult to examine clinically). Guide arthrocentesis. Rapidly available at bedside.
MRI
Best imaging for complications: adjacent osteomyelitis, soft tissue abscess, synovial enhancement. Order if poor response to treatment.
Kocher Criteria (Pediatric Hip, Septic vs Transient Synovitis)
Criteria
Points
Non-weight-bearing on affected side
1
Fever >38.5°C
1
WBC >12,000/μL
1
ESR >40 mm/hr
1
0 criteria: <0.2% risk • 1: 3% • 2: 40% • 3: 93% • 4: 99% probability of septic arthritis. CRP >20 mg/L added as 5th criterion in modified Kocher.
🚨 Management
Two Pillars: Drainage + Antibiotics
Both drainage AND antibiotics are required. Antibiotics alone are insufficient, purulent material destroys cartilage via proteolytic enzymes. Source control is mandatory.
Drainage Options
Method
When to Use
Key Points
Serial arthrocentesis (needle aspiration)
First-line for most accessible joints (knee, ankle, wrist, elbow)
Aspirate to dryness daily until effusion resolves. Monitor WBC trend, should decrease with effective treatment. Simple, bedside, repeatable.
Arthroscopic washout
Failed serial aspiration, loculated collection, shoulder
Better visualization, more thorough lavage. Can break adhesions/loculations. Preferred for shoulder (difficult to aspirate completely).
Open arthrotomy
Hip (always), failed arthroscopy, prosthetic joint, pediatric
Hip joint is deep and difficult to drain percutaneously, open surgical drainage is standard for septic hip. Also needed if hardware present or tissue necrosis.
Septic hip = surgical emergency. The hip joint cannot be adequately drained by needle aspiration, consult orthopedics immediately for open washout. In children, a septic hip can compromise femoral head blood supply and cause avascular necrosis.
Empiric Antibiotic Therapy
Scenario
Empiric Regimen
Duration
Notes
Native joint (typical)
Vancomycin 15–20 mg/kg IV q8–12h
2–4 weeks total (IV → PO step-down)
Covers MRSA + MSSA. Add ceftriaxone 2g IV daily if GNR suspected (elderly, immunocompromised, IVDU). De-escalate by culture.
Vancomycin + Ceftriaxone 2g IV daily or Cefepime 2g IV q8h
2–4 weeks
Cefepime if Pseudomonas risk (IVDU, recent hospitalization). Narrow by culture & sensitivity.
Disseminated gonococcal infection
Ceftriaxone 1g IV daily
7–14 days (switch to PO after improvement)
Treat until clinically improved (usually 24–48h IV) then step down to PO cefixime or azithromycin. Treat concomitant chlamydia (azithromycin 1g or doxycycline). Test + treat sexual partners.
Prosthetic joint infection (acute)
Vancomycin + Cefepime or Meropenem
6 weeks IV + chronic suppressive PO
ID + Orthopedics co-management. Options: DAIR (debridement, antibiotics, implant retention) if early (<30 days) and stable implant. Otherwise: 1-stage or 2-stage exchange arthroplasty.
IV-to-PO Transition & Duration
Switch to PO when: Clinical improvement (less pain, decreased effusion, defervesced), declining CRP, known organism with oral susceptibility, GI tract functioning
OVIVA trial evidence supports early PO step-down for bone and joint infections with equivalent outcomes to prolonged IV therapy OVIVA, 2019
Monitor: CRP trending down (best marker), clinical exam (pain, ROM, effusion), repeat aspiration if not improving
Ortho follow-up: Functional rehabilitation after infection clears, early PT to prevent joint stiffness and contracture
💊 Medications
Key Antibiotics for Septic Arthritis
Drug (Brand)
Mechanism
Dosing
Key Considerations
Vancomycin (Vancocin)
Glycopeptide, inhibits cell wall synthesis by binding D-Ala-D-Ala
15–20 mg/kg IV q8–12h Target AUC/MIC 400–600
Empiric MRSA coverage. Monitor trough or AUC. Nephrotoxic, monitor SCr. Red man syndrome with rapid infusion (rate-related, not allergy). Good synovial fluid penetration.
Ceftriaxone (Rocephin)
3rd-gen cephalosporin, inhibits PBPs
2g IV q24h
GNR coverage + gonococcal coverage. Once-daily dosing (long half-life). Do not use in neonates with bilirubin issues. Good bone/joint penetration.
Cefazolin (Ancef)
1st-gen cephalosporin
2g IV q8h
Step-down from vancomycin once MSSA confirmed. Excellent bone penetration. Can transition to PO cephalexin or dicloxacillin.
Nafcillin/Oxacillin
Anti-staphylococcal penicillin
2g IV q4h
Gold standard for MSSA. Excellent bone/joint penetration. Interstitial nephritis risk. Alternative: cefazolin (easier dosing).
Cefepime (Maxipime)
4th-gen cephalosporin
2g IV q8h
Pseudomonas coverage + GNR. Use when Pseudomonas risk (IVDU, nosocomial). CNS toxicity at high doses/renal impairment.
TMP-SMX (Bactrim)
Folate synthesis inhibitor
DS 1–2 tabs PO BID
Oral MRSA step-down option. Good bioavailability. Monitor K⁺ (hyperkalemia risk). Not for strep coverage (unreliable).
📋 On Rounds
What synovial fluid findings diagnose septic arthritis?
WBC >50,000/μL with >90% PMNs is the classic finding. Gram stain positive in 50–75%. Synovial fluid culture positive in 70–90%. However, partially-treated infections may have lower counts. Any WBC >25,000 with clinical suspicion warrants empiric treatment pending cultures. Crystals do NOT exclude infection.
Why does a septic hip always require open surgical drainage?
The hip is a deep ball-and-socket joint that cannot be adequately drained by needle aspiration. Increased intra-articular pressure from purulent effusion can compress the retinacular blood supply to the femoral head, causing avascular necrosis. In children, the femoral head blood supply is especially vulnerable. Open arthrotomy allows thorough washout, debridement, and pressure decompression.
How do you distinguish gonococcal from non-gonococcal septic arthritis?
Can gout and septic arthritis coexist? How do you manage this?
Yes, crystals + infection coexist in ~5% of cases. Finding MSU or CPPD crystals does NOT rule out septic arthritis. If clinical suspicion remains (fever, WBC >50K, risk factors), treat empirically with antibiotics AND drainage until cultures return. A common pitfall is attributing a hot joint to gout alone and missing concomitant infection.
What are the Kocher criteria and when are they used?
The Kocher criteria distinguish septic arthritis from transient synovitis in pediatric hip pain: (1) non-weight-bearing, (2) fever >38.5°C, (3) WBC >12,000, (4) ESR >40. With 0 criteria: <0.2% risk; 4 criteria: 99% risk. CRP >20 added as modified 5th criterion. ≥2 criteria warrant aspiration under sedation/US guidance.
📣 Sample Presentation
One-Liner
"Mr. Davis is a 68-year-old man with diabetes and rheumatoid arthritis on methotrexate presenting with 2 days of acute right knee swelling, pain, and inability to bear weight, with fever to 39.1°C. Arthrocentesis showed WBC 78,000 with 95% PMNs and positive Gram stain for gram-positive cocci in clusters, consistent with septic arthritis."
Key Points to Cover on Rounds
Septic arthritis of right knee, synovial fluid WBC 78,000, >95% PMNs, Gram stain with GPC in clusters (likely S. aureus). Started vancomycin empirically, awaiting final culture and sensitivities. Serial arthrocentesis performed, aspirated 45 mL of purulent fluid. Blood cultures ×2 sent. CRP 185. Orthopedics consulted, will reassess for arthroscopic washout if not improving with serial aspiration. Held methotrexate given active infection. Plan to narrow antibiotics by culture. Target 4-week course if S. aureus confirmed. Early PT once infection controlled.
⚡ Summary
Summary
The Clock Is 24 to 48 Hours
Delay in drainage and antibiotics leads to irreversible cartilage destruction within 24 to 48 h.The knee is the commonest joint. A hot, swollen, exquisitely painful joint with severe pain on any passive movement is septic arthritis until the fluid says otherwise.
Aspirate Before Antibiotics When You Can
Synovial fluid is the diagnostic test, and a single dose of antibiotic can render the culture negative.Do not delay antibiotics in a septic patient, but in a stable one the aspirate comes first, and it should be arranged in hours rather than overnight.
Read the Synovial Fluid
WBC above 50,000 with more than 90% neutrophils is the hallmark, with a low glucose and a positive Gram stain in about half. No single cutoff excludes it: counts between 20,000 and 50,000 can be septic, particularly early, in prosthetic joints and in the immunocompromised. Crystals do not rule out infection, since gout and sepsis coexist, so send culture regardless.
Two Pillars: Drainage Plus Antibiotics
Antibiotics alone do not treat a septic joint, because pus under pressure destroys cartilage and antibiotic penetration into a purulent joint is poor. Serial needle aspiration, arthroscopic washout or open arthrotomy, with arthroscopy usually preferred for large joints, and the hip and any prosthetic joint go to the operating room.
Cover Staph Empirically
S. aureus is the commonest organism overall and MRSA is common enough that vancomycin is the empiric backbone. Add gram-negative cover in the elderly, the immunocompromised, injection drug users and after trauma. Narrow when culture and susceptibilities return.
Ask About Gonococcal Disease in the Young and Sexually Active
Disseminated gonococcal infection presents either as a purulent monoarthritis or as the triad of migratory polyarthralgia, tenosynovitis and pustular skin lesions.Synovial cultures are often negative, so send urethral, cervical, rectal and pharyngeal NAAT.It responds rapidly to ceftriaxone and rarely needs surgical drainage, which is the opposite of staphylococcal disease.
Use Kocher for the Limping Child
Fever above 38.5°C, non-weight-bearing, ESR above 40, and WBC above 12,000.The probability of septic arthritis of the hip rises steeply with the number of criteria met, and it is what separates it from transient synovitis. A child who will not bear weight at all deserves an aspirate.
Treat Long Enough and Follow the Joint
2 to 4 weeks total for most organisms, longer for S. aureus and for prosthetic joints, with an IV-to-oral switch once the patient is improving and the organism is susceptible to a well-absorbed oral agent. Repeat aspiration if the joint does not settle.Start physical therapy early, since a joint immobilized through the infection stiffens permanently, and look for the source, since most septic joints are hematogenous.
Central line–associated bloodstream infections (CLABSI) are among the most common and preventable healthcare-associated infections. The decision to remove vs salvage the line depends on the organism, patient stability, and line necessity. S. aureus and Candida CLABSI mandate line removal. Coagulase-negative Staph may be treated with lock therapy if the line is essential.
🔍 Overview
Key Concepts
CLABSI: Laboratory-confirmed bloodstream infection in a patient with a central line in place for >2 calendar days, where the infection is not related to another source
CRBSI: Catheter-related BSI, clinical definition requiring paired cultures showing differential time to positivity (≥2 hours) or quantitative culture from catheter tip ≥15 CFU (Maki roll-plate)
Incidence: ~0.8–1.2 per 1,000 catheter-days in ICU (national average). Zero is the goal.
Mortality: 12–25% attributable mortality. Each CLABSI adds ~$46,000 in healthcare costs and 7–10 extra hospital days.
Most common lines: Non-tunneled CVC (highest risk) > PICC > tunneled CVC > implanted port (lowest risk)
Microbiology
Organism
Frequency
Key Points
Coagulase-negative Staphylococci (CoNS: S. epidermidis)
~35%
Most common overall. Biofilm-formers. Often low-virulence. May be contaminant, need ≥2 positive sets to confirm. Line salvage sometimes possible with lock therapy.
Staphylococcus aureus
~15–20%
Line MUST be removed. High risk of metastatic seeding (endocarditis, osteomyelitis, epidural abscess). Always get TTE/TEE. Minimum 4–6 weeks if complicated. ID consult mandatory.
Enterococcus spp.
~10%
E. faecalis (ampicillin-susceptible) vs E. faecium (often VRE). GI source possible. Remove line if possible.
Gram-negative rods
~20%
Klebsiella, E. coli, Enterobacter, Pseudomonas, Acinetobacter. Consider GI/GU source. Pseudomonas, strong indication to remove line.
Candida spp.
~10–15%
Line MUST be removed. Start echinocandin empirically. Ophthalmology consult (endophthalmitis). Blood cultures must be negative ×2 before stopping antifungals. Treat ≥14 days from first negative culture.
Prevention, Central Line Bundle
Prevention is the best treatment. Central line bundles reduce CLABSI by 50–70%. Compliance must be monitored daily.
Chlorhexidine skin antisepsis (2% CHG in 70% isopropyl alcohol), allow to dry completely
Optimal site selection: Subclavian preferred (lowest infection rate), avoid femoral when possible (highest rate). Internal jugular intermediate.
Daily review of line necessity, remove as soon as no longer needed (“line rounds”)
CHG-impregnated dressings (Biopatch), change every 7 days or if soiled/loose
Scrub the hub: 15-second scrub of catheter hub with alcohol or CHG before every access
🧪 Workup
Diagnostic Approach
Test
How
Interpretation
Paired blood cultures (gold standard)
Draw one set from each lumen of the central line AND one set from a peripheral vein. Label clearly.
Differential time to positivity (DTP): If central line culture turns positive ≥2 hours before peripheral = strongly suggests CRBSI (sensitivity 85%, specificity 91%).
Peripheral blood cultures alone
≥2 sets from separate peripheral sites
If line cannot be accessed or has been removed. Two sets positive with same organism = true bacteremia (especially important for CoNS).
Catheter tip culture (Maki roll-plate)
If line is removed: roll 5-cm distal tip across blood agar
≥15 CFU with same organism growing from peripheral blood = CRBSI confirmed. Only useful if line is removed. Do NOT routinely culture tips of removed lines without clinical suspicion.
Always draw peripheral cultures. Central-line-only cultures have a high false-positive rate (hub colonization). Without paired peripherals, you cannot distinguish CRBSI from contamination. Two sets of CoNS from the line alone = insufficient to diagnose CLABSI.
When to Suspect CLABSI
Fever, rigors, or hemodynamic instability in a patient with a central line and no other obvious source
Exit site erythema, purulence, or tenderness (suggests local infection ± CRBSI)
Bacteremia with typical line organisms (CoNS, S. aureus, Candida) without another clear source
New-onset sepsis within 48h of central line insertion or manipulation
Rule out other sources first: UTI, pneumonia, surgical site, intra-abdominal, CLABSI is a diagnosis of exclusion per NHSN criteria
Additional Workup for S. aureus Bacteremia
Every S. aureus bacteremia requires:
Repeat blood cultures every 24–48 hours until negative (document clearance)
Echocardiography: TEE preferred (sensitivity 90–100% vs TTE 60–70% for endocarditis). Order on ALL S. aureus BSIs.
ID consult, proven to reduce mortality and relapse in S. aureus bacteremia Fowler et al., 2003
Look for metastatic foci: Osteomyelitis, epidural abscess, septic arthritis, septic emboli. MRI spine if back pain. Fundoscopic exam.
Duration depends on classification: Uncomplicated (removable focus, negative TEE, clearance ≤72h, no metastatic infection) = 2 weeks. Complicated = 4–6 weeks.
🚨 Management
Line Removal vs Salvage, Decision Framework
Organism
Remove Line?
Rationale
S. aureus
ALWAYS REMOVE
High risk of metastatic complications (endocarditis 25–30% if line retained). Biofilm impossible to eradicate with antibiotics alone. No exceptions.
Candida spp.
ALWAYS REMOVE
Cannot clear candidemia without removing focus. Each day of retained line increases mortality. Remove within 24 hours of positive culture.
Pseudomonas
STRONGLY RECOMMEND
Biofilm-former, difficult to eradicate. High failure rate with salvage. Remove unless truly irreplaceable.
GNRs (other)
REMOVE if possible
Preferred to remove. Salvage may be attempted with lock therapy in truly essential, difficult-to-replace lines + clinical improvement.
Enterococcus
REMOVE if possible
Remove preferred. VRE especially, limited treatment options make salvage risky.
CoNS (S. epidermidis)
SALVAGE may be attempted
Low-virulence organism. Salvage with antibiotic lock therapy + systemic antibiotics if line is truly essential (e.g., tunneled HD catheter, long-term TPN). Remove if failing, tunnel infection, or port pocket infection.
Empiric Antibiotic Therapy
Scenario
Empiric Regimen
Notes
Standard empiric
Vancomycin IV (MRSA/CoNS coverage)
Start immediately after cultures drawn. De-escalate by culture within 48–72h.
+ GNR risk (ICU, immunocompromised, femoral line)
Vancomycin + Cefepime or Piperacillin-tazobactam
Add GNR coverage if severely ill, recent GNR colonization, or ICU patient. Cefepime for Pseudomonas risk.
Add Micafungin 100 mg IV daily or Caspofungin 70 mg → 50 mg IV daily
Echinocandin preferred empirically (covers C. glabrata/krusei which are fluconazole-resistant). De-escalate to fluconazole if C. albicans + susceptible.
Treatment Duration by Organism
Organism
Duration (after line removal)
Key Points
CoNS
5–7 days (if line removed) 10–14 days (if line salvaged + lock therapy)
Shortest course. Ensure ≥2 sets positive (not contaminant). If single set positive, likely contaminant, may not need treatment.
S. aureus
Minimum 4 weeks (2 weeks ONLY if ALL uncomplicated criteria met)
Uncomplicated: removable focus removed, negative TEE, clearance ≤72h, no implanted hardware, no metastatic infection. ID consult mandatory. 2-week course only with ALL criteria met.
Enterococcus
7–14 days
Ampicillin for susceptible E. faecalis. Daptomycin or linezolid for VRE (E. faecium).
GNRs
7–14 days
Narrow by sensitivities. Pseudomonas: 7–14 days with an anti-pseudomonal agent. May need combo therapy if MDR.
Candida
14 days from first negative blood culture
Repeat cultures every 24–48h until negative. Ophthalmology consult (endophthalmitis in 10–15%). Remove line within 24h. Echinocandin → fluconazole step-down if susceptible.
Antibiotic Lock Therapy
Indication: Line salvage attempt for CoNS or low-virulence organisms when line is essential and cannot be easily replaced
How: Instill concentrated antibiotic solution (vancomycin 5 mg/mL or daptomycin 5 mg/mL + heparin) into each lumen, dwell for ≥12 hours (ideally when line not in use)
Duration: 10–14 days of lock therapy + systemic antibiotics simultaneously
Contraindicated: S. aureus, Candida, Pseudomonas, tunnel infection, port pocket infection, septic shock
Success rate: ~65–80% for CoNS. Failure (persistent positive cultures) = remove line
💊 Medications
Key Antibiotics for CLABSI
Drug (Brand)
Spectrum
Dosing
Key Considerations
Vancomycin (Vancocin)
MRSA, CoNS, Enterococcus (non-VRE)
15–20 mg/kg IV q8–12h Target AUC/MIC 400–600
Empiric backbone for all CLABSI. Monitor AUC-guided dosing. Nephrotoxic, check BMP daily. Lock concentration: 5 mg/mL.
Daptomycin (Cubicin)
MRSA, VRE, CoNS
6–8 mg/kg IV q24h (10–12 mg/kg for VRE endocarditis)
Alternative to vancomycin for MRSA BSI. Check weekly CPK (rhabdomyolysis). Inactivated by surfactant, cannot use for pneumonia. Excellent for BSI and endocarditis.
Cefazolin (Ancef)
MSSA
2g IV q8h
Step-down from vancomycin once MSSA confirmed. Preferred over vancomycin for MSSA (better outcomes).
Micafungin (Mycamine)
Candida spp. (including C. glabrata)
100 mg IV q24h
Echinocandin, first-line empiric for candidemia. Fungicidal against Candida. Few drug interactions. Well-tolerated.
Fluconazole (Diflucan)
C. albicans, C. parapsilosis
400–800 mg IV/PO daily
Step-down from echinocandin once C. albicans confirmed + susceptible. NOT for C. glabrata (often resistant) or C. krusei (intrinsically resistant).
Linezolid (Zyvox)
VRE, MRSA
600 mg IV/PO BID
VRE option. 100% oral bioavailability. Limit to ≤2 weeks if possible (thrombocytopenia, serotonin syndrome, optic neuropathy with prolonged use). Check weekly CBC.
📋 On Rounds
When must you ALWAYS remove the central line in CLABSI?
Always remove for: (1) S. aureus, (2) Candida, (3) Pseudomonas. Also remove for tunnel infection, port pocket infection, septic shock, septic thrombophlebitis, and endocarditis. S. aureus and Candida form biofilms that cannot be eradicated with antibiotics alone, and retained lines dramatically increase mortality and metastatic complications.
How do you use differential time to positivity (DTP) to diagnose CRBSI?
Draw paired blood cultures simultaneously from the central line AND a peripheral vein. If the central line culture turns positive ≥2 hours before the peripheral culture, it strongly suggests the line is the source (CRBSI). Sensitivity ~85%, specificity ~91%. This avoids unnecessary line removal when the source is elsewhere.
Why does every S. aureus bacteremia need a TEE?
S. aureus has a 25–30% rate of endocarditis in bacteremia, even when a removable source (like a line) is identified. TTE sensitivity is only 60–70%, it misses small vegetations. TEE sensitivity is 90–100%. Finding endocarditis changes duration from 2 weeks to 4–6 weeks and may require surgery. ID consult is also mandatory, reduces mortality.
What is the central line insertion bundle and why does it matter?
The central line bundle reduces CLABSI by 50–70%: (1) hand hygiene, (2) maximal barrier precautions (full drape, cap, mask, gown, gloves), (3) chlorhexidine skin prep, (4) optimal site (subclavian preferred, avoid femoral), (5) daily line necessity review. Also: CHG-impregnated dressings, scrub the hub ×15 sec, daily line rounds. Prevention is the single most impactful intervention.
How do you manage candidemia from a central line?
(1) Remove the line within 24 hours. (2) Start echinocandin (micafungin 100 mg or caspofungin) empirically. (3) Repeat blood cultures every 24–48h until negative. (4) Ophthalmology consult for endophthalmitis screening (occurs in 10–15%). (5) Treat for 14 days after first negative blood culture. Step down to fluconazole if C. albicans + susceptible. Species identification matters, C. glabrata and C. krusei need echinocandins.
📣 Sample Presentation
One-Liner
"Mrs. Rodriguez is a 72-year-old woman with metastatic ovarian cancer and a tunneled Hickman catheter presenting with fever, rigors, and hypotension. Blood cultures from the line turned positive at 8 hours for gram-positive cocci in clusters, 3 hours before peripheral cultures, consistent with CLABSI."
Key Points to Cover on Rounds
Likely CLABSI, DTP 3 hours (line positive first). Started vancomycin empirically. Speciation pending, if S. aureus, will remove line immediately, consult ID, and get TEE. If CoNS, will discuss line salvage vs removal given need for ongoing chemotherapy. Surveillance cultures drawn every 24h. CRP 145, lactate 2.8. Hemodynamically improved after 2L bolus. Will de-escalate antibiotics once cultures finalize. Line has been in place 42 days with no prior infections.
⚡ Summary
Summary
Prevention Beats Everything
Central line bundles reduce CLABSI by 50 to 70%: hand hygiene, full barrier precautions at insertion, chlorhexidine skin prep, avoiding the femoral site, and daily review of whether the line is still needed. That last item is the one that lapses, and the commonest reason a line becomes infected is that nobody asked whether it could come out.
Suspect It When There Is No Other Source
Fever or sepsis in a patient with a central line and no alternative explanation. Local signs at the exit site are helpful but frequently absent, so their absence does not exclude it. Draw paired blood cultures, one peripheral and one from each lumen, before antibiotics.
Differential Time to Positivity Makes the Diagnosis
A line culture turning positive 2 or more hours before the peripheral culture indicates the catheter is the source. This is what distinguishes a true CLABSI from a bacteremia the line merely sampled, and it decides whether the line has to come out.
Some Organisms Mean the Line Comes Out, No Debate
S. aureus, Candida, Pseudomonas, and any rapidly growing mycobacterium. Also remove the line in septic shock, a tunnel or pocket infection, persistent bacteremia beyond 72 h of appropriate therapy, or endocarditis and other metastatic infection.Attempting salvage in these situations causes relapse and metastatic seeding.
Salvage Is Possible Only in Narrow Circumstances
A stable patient, with coagulase-negative staphylococci or a similarly low-virulence organism, and limited vascular access.Use systemic antibiotics plus antibiotic lock therapy, which delivers a high drug concentration into the lumen where the biofilm is, since systemic levels never reach it. Recheck cultures and abandon salvage if they do not clear.
Empiric Therapy Covers Staph, Then Widens by Risk
Vancomycin for MRSA and coagulase-negative staphylococci.Add gram-negative and antipseudomonal cover for the neutropenic, the critically ill, and femoral lines.Add an echinocandin for suspected candidemia in a patient on TPN, prolonged broad-spectrum antibiotics, or with known colonization. Narrow as soon as the organism is known.
Duration Is Set by Organism, Not by Symptoms
Coagulase-negative staphylococci: 5 to 7 days after removal. Enterococcus and gram-negatives: 7 to 14 days. S. aureus: at least 14 days, and 4 to 6 weeks with complicated infection.Candida: 14 days after the first negative blood culture, with all lines removed and a dilated eye exam.
S. aureus Bacteremia Needs a Full Workup
Repeat blood cultures every 48 to 72 h until they clear, get an echocardiogram (TEE if the TTE is negative and suspicion persists), and look for metastatic foci, above all vertebral osteomyelitis, epidural abscess and septic arthritis. Get infectious diseases involved, which independently improves outcomes in S. aureus bacteremia. Never treat it as a contaminant.
Intra-abdominal infections (IAI) range from uncomplicated appendicitis to life-threatening peritonitis and hepatic abscess. Source control (surgery, drainage, or percutaneous intervention) is the cornerstone, antibiotics alone are insufficient for complicated IAI. Empiric coverage must include gram-negatives AND anaerobes. SBP in cirrhotics is a distinct entity requiring paracentesis and rapid antibiotics.
🔍 Overview
Classification
Type
Definition
Examples
Uncomplicated IAI
Infection confined to a single organ, no peritoneal contamination
Persistent/recurrent peritonitis after initially adequate source control
Often nosocomial organisms (Enterococcus, Candida, resistant GNRs). High mortality. ICU population.
Common Intra-Abdominal Infections
Condition
Presentation
Key Management
SBP
Cirrhotic + ascites + fever, abdominal pain, AMS, worsening encephalopathy. May be subtle.
Diagnostic paracentesis: PMN ≥250/mm³ = SBP. Start ceftriaxone 2g IV daily. Albumin 1.5 g/kg day 1, 1 g/kg day 3 (if Cr >1, BUN >30, or bilirubin >4). No source control needed.
Emergency biliary drainage (ERCP or PTC) within 24h for severe cholangitis. Antibiotics: pip-tazo or ceftriaxone + metronidazole. Blood cultures. Fluid resuscitation.
Intra-abdominal abscess
Persistent fever despite antibiotics, localized pain, elevated WBC/CRP. Often post-surgical.
Percutaneous drainage (CT or US-guided) is first-line. Surgery if not drainable percutaneously, multiloculated, or associated with fistula. Antibiotics alone insufficient for large (>3 cm) abscesses.
Perforated viscus
Acute abdomen: sudden severe pain, rigidity, rebound, guarding. Free air on imaging.
Emergent surgery. Broad-spectrum antibiotics immediately. NPO, IV fluids, NG tube. Mortality increases with each hour of delay.
Small abscess (<3 cm): antibiotics alone. Large abscess: percutaneous drainage + antibiotics. Perforation with diffuse peritonitis: emergent surgery (Hartmann procedure).
Secondary peritonitis
Diffuse abdominal pain and tenderness, fever, sepsis following perforation or leak.
Source control is paramount (surgery to repair perforation, drain contamination). Broad-spectrum antibiotics. Polymicrobial: GNR + anaerobes + sometimes enterococcus.
Microbiology
Community-acquired cIAI: E. coli (most common), Klebsiella, Strep spp., Bacteroides fragilis (key anaerobe). Usually susceptible to standard empiric regimens.
SBP: Monomicrobial, E. coli (#1), Klebsiella, Strep pneumoniae. If polymicrobial on culture, suspect secondary peritonitis (perforation).
Biliary: E. coli, Klebsiella, Enterococcus, Bacteroides. Cholangitis may have Enterococcus more frequently than other cIAI.
Polymicrobial culture from ascites = red flag. SBP is monomicrobial. If multiple organisms grow from peritoneal fluid, suspect secondary peritonitis (bowel perforation) and get urgent CT imaging, the patient may need surgery, not just antibiotics.
🧪 Workup
Diagnostic Approach
Test
When
Key Points
CT abdomen/pelvis with IV contrast
First-line imaging for most cIAI
Gold standard for IAI. Detects abscess, free air, perforation, bowel wall thickening, mesenteric stranding. Sensitivity >95% for abscess. Guides percutaneous drainage.
Diagnostic paracentesis
ALL cirrhotics admitted with ascites
PMN ≥250/mm³ = SBP (start antibiotics immediately). Send: cell count + differential, culture (inoculate blood culture bottles at bedside for best yield), albumin, total protein, glucose, LDH, gram stain.
Positive in 30–50% of SBP, higher in cholangitis. Essential for targeted therapy.
CBC, CMP, lipase, lactate
All suspected IAI
Leukocytosis (or leukopenia in severe sepsis). Elevated lactate = tissue hypoperfusion, surgical urgency. LFTs for biliary etiology. Lipase if pancreatitis in differential.
Upright chest X-ray / KUB
Suspected perforation (rapid screening)
Free air under diaphragm = perforation until proven otherwise. Sensitivity ~80% for pneumoperitoneum. CT is more sensitive if clinical suspicion persists with negative X-ray.
MRCP / ERCP
Biliary obstruction, cholangitis
MRCP: non-invasive biliary imaging. ERCP: therapeutic (stone extraction, stent placement) + diagnostic. Emergent ERCP for severe cholangitis.
SBP Diagnostic Criteria
Finding
Interpretation
Ascitic PMN ≥250/mm³
= SBP. Start empiric antibiotics immediately. Do not wait for culture.
Positive ascitic culture + PMN <250
= Bacterascites. May resolve spontaneously. Repeat paracentesis in 48h, if PMN rises to ≥250, treat as SBP.
PMN ≥250 + negative culture
= Culture-negative neutrocytic ascites (CNNA). Still SBP, treat the same. Cultures are negative in ~40% of SBP.
Ascitic fluid total protein >1 g/dL, glucose <50, LDH > serum
Suggests secondary peritonitis (perforation). Get urgent CT. Surgical evaluation.
Polymicrobial ascitic fluid culture
Secondary peritonitis until proven otherwise. CT + surgical consult.
🚨 Management
Principles of Management
Source control + antibiotics. Antibiotics alone are insufficient for complicated IAI with abscess, perforation, or necrosis. Identify and address the source: surgery (repair perforation, resection), percutaneous drainage (abscess), or endoscopic intervention (ERCP for cholangitis).
Empiric Antibiotic Therapy
Scenario
Empiric Regimen
Notes
Community-acquired, mild-moderate cIAI
Ceftriaxone 2g IV daily + Metronidazole 500 mg IV q8h orErtapenem 1g IV daily
Covers GNRs + anaerobes. Ertapenem is single-agent option. No Pseudomonas or Enterococcus coverage needed for mild community-acquired. SIS/IDSA, 2010
Community-acquired, severe cIAI (sepsis, peritonitis)
Piperacillin-tazobactam 4.5g IV q6h orMeropenem 1g IV q8h
Broader coverage for sicker patients. Pip-tazo covers GNRs + anaerobes + Enterococcus. Meropenem for ESBL risk or penicillin allergy (severe).
Healthcare-associated / post-surgical
Meropenem 1g IV q8h or Pip-tazo + Vancomycin ± Fluconazole/Echinocandin
Broader coverage for resistant organisms (ESBL, Pseudomonas, VRE, Candida). Add vancomycin if MRSA/VRE risk. Add antifungal if Candida risk (prior surgery, TPN, broad-spectrum antibiotics). De-escalate aggressively by culture.
SBP (primary peritonitis)
Ceftriaxone 2g IV daily orCefotaxime 2g IV q8h
Covers E. coli, Klebsiella, Strep pneumo. Do NOT add anaerobic coverage (SBP is monomicrobial, rarely anaerobic). Add albumin (1.5 g/kg day 1, 1 g/kg day 3), reduces mortality Sort, 1999
Cholangitis
Pip-tazo 4.5g IV q6h orCeftriaxone + Metronidazole
Covers biliary pathogens (E. coli, Klebsiella, Enterococcus, Bacteroides). Priority: biliary drainage (ERCP) within 24h for severe cholangitis. Add vancomycin if healthcare-associated or concern for resistant Enterococcus.
Source Control by Condition
Condition
Source Control
Timing
Perforated viscus
Emergent surgery (repair, resection, washout)
ASAP, minutes to hours. Mortality increases with delay.
Acute cholangitis
ERCP with stone extraction/stent ± sphincterotomy
Within 24h (urgent). Emergent if severe sepsis/shock.
Acute cholecystitis
Cholecystectomy (lap chole) or percutaneous cholecystostomy if too sick for surgery
Within 72h preferred (early cholecystectomy). Perc chole if unstable/high surgical risk.
Intra-abdominal abscess
Percutaneous CT-guided drainage (first-line). Surgery if not amenable.
Within 24–48h of identification. Small (<3 cm) may resolve with antibiotics alone.
SBP
None, antibiotics only (no perforation)
Antibiotics immediately upon diagnosis (PMN ≥250)
Complicated diverticulitis with abscess
Small abscess (<3 cm): antibiotics. Larger: perc drain. Diffuse peritonitis: surgery.
Abscess drain within 24–48h. Surgery emergent if free perforation.
Duration of Therapy
Adequate source control achieved: 4 days (96 hours) of antibiotics is sufficient for most cIAI STOP-IT, 2015
Inadequate source control: Continue antibiotics until source control achieved + clinical improvement. No fixed duration.
SBP: 5 days of ceftriaxone (or until PMN <250 on repeat paracentesis at 48h)
Cholangitis: 4–7 days after successful biliary drainage
Bacteremia: If concurrent bacteremia, treat per BSI guidelines (typically 7–14 days from first negative culture)
STOP-IT trial: In cIAI with adequate source control, 4 days of antibiotics had similar outcomes to traditional longer courses (median 8 days). Shorter is better when the source is controlled, reduces resistance, C. diff risk, and cost.
💊 Medications
Key Antibiotics for Intra-Abdominal Infections
Drug (Brand)
Spectrum
Dosing
Key Considerations
Piperacillin-Tazobactam (Zosyn)
GNRs + anaerobes + Enterococcus + Pseudomonas
4.5g IV q6h (or 3.375g q6h extended infusion)
Workhorse for cIAI. Broad-spectrum single agent. Extended infusion (over 4h) improves PK. Does NOT cover ESBL-producers or MRSA.
Reserve for healthcare-associated or ESBL risk. Does NOT cover MRSA or VRE. Seizure risk (lower than imipenem). Excellent penetration.
Ceftriaxone (Rocephin)
GNRs (not Pseudomonas)
2g IV q24h
Community-acquired cIAI backbone. Must pair with metronidazole for anaerobic coverage. SBP monotherapy. Once-daily dosing.
Metronidazole (Flagyl)
Anaerobes (Bacteroides fragilis)
500 mg IV/PO q8h
Anaerobic coverage when using non-anaerobic-active GNR agents (ceftriaxone, fluoroquinolones). Excellent oral bioavailability. Disulfiram reaction with alcohol. Metallic taste.
Ertapenem (Invanz)
GNRs (incl ESBL) + anaerobes. NOT Pseudomonas.
1g IV q24h
Once-daily carbapenem for community-acquired cIAI. DOES cover ESBL. Does NOT cover Pseudomonas, Acinetobacter, or Enterococcus. Good for step-down OPAT.
Ciprofloxacin (Cipro)
GNRs (incl Pseudomonas)
400 mg IV q12h or 500 mg PO BID
Alternative for penicillin/cephalosporin allergy. Pair with metronidazole. Rising resistance limits empiric use. Check local antibiogram. FDA black box warnings (tendon, neuropathy).
📋 On Rounds
What is the diagnostic threshold for SBP and what should you do immediately?
Ascitic fluid PMN ≥250/mm³ = SBP. Start ceftriaxone 2g IV daily immediately, do not wait for cultures (40% will be culture-negative). Add IV albumin (1.5 g/kg day 1, 1 g/kg day 3) if Cr >1, BUN >30, or bilirubin >4, reduces hepatorenal syndrome and mortality (Sort trial). Treat for 5 days. No source control needed.
Why is source control more important than antibiotics in complicated IAI?
Antibiotics cannot sterilize undrained collections or dead tissue. Abscesses have low blood flow and low antibiotic penetration. Necrotic tissue and pus are incubators for ongoing bacterial growth. Without source control, antibiotics will fail, the patient will remain septic despite broadest-spectrum coverage. Source control (drain abscess, repair perforation, remove necrotic tissue) is the definitive treatment; antibiotics are adjunctive.
How does the STOP-IT trial change antibiotic duration for IAI?
The STOP-IT trial (2015) showed that 4 days (96 hours) of antibiotics after adequate source control is equivalent to traditional longer courses (median 8 days) for complicated IAI. No difference in surgical site infection, recurrent IAI, or death. Shorter courses reduce antibiotic exposure, C. diff risk, resistance emergence, and cost. Key requirement: adequate source control must be achieved first.
What does polymicrobial growth from ascitic fluid tell you?
Polymicrobial ascitic fluid culture suggests secondary peritonitis (bowel perforation or surgical leak), not SBP. SBP is almost always monomicrobial. Additional clues: ascitic protein >1 g/dL, glucose <50 mg/dL, LDH > serum upper limit. This is a surgical emergency, get urgent CT abdomen and surgical consultation. The patient needs source control, not just antibiotics.
What is Charcot's triad and Reynolds' pentad?
Charcot triad (cholangitis): (1) fever/chills, (2) jaundice, (3) RUQ pain. Present in ~50–70% of cholangitis. Reynolds pentad adds: (4) altered mental status, (5) hypotension/shock. Reynolds pentad indicates severe/suppurative cholangitis with sepsis, requires emergent biliary drainage (ERCP). Do not wait for imaging to start antibiotics if Reynolds pentad is present.
📣 Sample Presentation
One-Liner
"Mr. Thompson is a 58-year-old man with decompensated cirrhosis (Child-Pugh C) admitted with fever, diffuse abdominal pain, and worsening hepatic encephalopathy. Diagnostic paracentesis showed PMN 820/mm³, consistent with spontaneous bacterial peritonitis."
Key Points to Cover on Rounds
SBP diagnosed by ascitic PMN 820, started ceftriaxone 2g IV daily. Ascitic fluid culture sent in blood culture bottles at bedside. Blood cultures ×2 drawn. IV albumin 1.5 g/kg given (Cr 1.4, BUN 38) per Sort trial protocol, day 3 albumin 1 g/kg planned. BMP monitoring for hepatorenal syndrome. Lactulose continued for encephalopathy. Repeat paracentesis planned at 48h to confirm ≥25% PMN decrease. Will complete 5-day course. SBP prophylaxis (ciprofloxacin or TMP-SMX) to be started after treatment for secondary prevention.
⚡ Summary
Summary
Source Control Plus Antibiotics
Antibiotics alone are insufficient in complicated intra-abdominal infection.Identify and address the source: surgery for perforation or ischemic bowel, percutaneous drainage for an abscess, ERCP for biliary obstruction. Failure to achieve source control is the commonest reason a patient does not improve on apparently correct antibiotics.
Separate Uncomplicated From Complicated
Uncomplicated infection is confined to a single organ with no peritoneal spread and can often be treated with antibiotics alone. Complicated infection extends beyond the organ into the peritoneum, with abscess or perforation, and needs a drainage or surgical plan from the outset.
The Flora Is Predictable
Enteric gram-negatives (E. coli, Klebsiella), anaerobes (Bacteroides fragilis) and enterococci.Coverage must include anaerobes for any infection below the diaphragm involving the bowel. Add Candida and resistant organisms in healthcare-associated, post-operative and immunocompromised cases, and in upper GI perforation.
Community Versus Healthcare-Associated Drives the Regimen
Community-acquired: ceftriaxone plus metronidazole, or ertapenem.Healthcare-associated or severe: piperacillin-tazobactam, or a carbapenem, with the addition of MRSA and antifungal cover where the risk profile warrants it. Narrow as soon as the cultures and the source are known.
A Polymicrobial Ascitic Culture Is a Red Flag
SBP is monomicrobial.If multiple organisms grow from peritoneal fluid, suspect secondary peritonitis from a perforated viscus, get urgent CT imaging, and recognize that the patient may need an operation rather than more antibiotics. Treating a perforation as SBP is fatal.
Short Courses Are Enough After Source Control
About 4 days of antibiotics after adequate source control (STOP-IT showed a fixed short course was equivalent to treating until physiologic normalization). Longer courses select resistance and cause C. difficile without improving outcomes.Extend only when source control is inadequate or incomplete.
Do Not Drain What Should Be Operated On, or Vice Versa
A well-defined, accessible abscess is drained percutaneously.Diffuse peritonitis, ischemic or perforated bowel, and failed percutaneous drainage go to the operating room.Diverticular abscess above about 4 cm drains; a smaller one often resolves on antibiotics alone.
Reassess at 48 to 72 Hours
Failure to improve means the source has not been controlled, the abscess is undrained or has recurred, or the organism is not covered.Re-image rather than simply broadening the antibiotic, which is the reflex that delays the reoperation these patients actually need.
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