Built for Residents
The resident's
pocket brain.
Protocols, drug guides, calculators, and clinical pearls backed by landmark trials and the latest guidelines. Organized by rotation, ready at the bedside.
🚨
View →
Surviving Sepsis Campaign 2026
129 statements, 46 new recommendations. NEWS/MEWS replaces qSOFA. Full 2021 vs 2026 comparison.
💎 Pearl of the Day
Loading pearl...
Rotations
🫁
ICU / Critical Care
23 topics
❤️
Cardiology
16 topics
🫁
Pulmonology
10 topics
🫀
Gastroenterology
12 topics
🧬
Nephrology
11 topics
🦠
Infectious Disease
12 topics
🧠
Neurology
9 topics
🚨
Emergency Medicine
11 topics
🌙
Night Float
Cross-cover guide
🏥
General Wards
10 topics
🩸
Hematology / Oncology
19 topics
⚗️
Endocrinology
16 topics
🦴
Rheumatology
10 topics
🕊️
Palliative Care
8 topics
🏠
Ambulatory / Outpatient
23 topics
Quick Reference
🫀
ACLS & Code Blue
H's and T's
📈
ECG Interpretation
Must-know patterns
💊
Antibiotic Guide
Empiric coverage
💧
IV Fluid Guide
NS vs LR vs D5W
⚡
Electrolyte Replacement
K, Mg, PO4, Ca
🧪
Lab Interpretation
CBC, BMP, LFTs, Coags
🩺
Procedures
Central line, LP, Para
💩
Bowel Regimen
Constipation protocol
🩸
Anticoag Reversal
PCC, Idarucizumab
🔄
Pain & Conversions
Opioid & steroid equiv
🌙
Night Float
Cross-cover algorithms
📋
Admission Orders
I-PASS sign-out
🔬
Radiology
CXR & CT interpretation
💉
Vasopressors
Norepi, Vaso, Levo
🩹
Insulin Guide
Basal-bolus protocol
⚠️
Drug Interactions
QT & serotonin syndrome
😴
Sedation Guide
RASS & sedation protocols
💊
Analgesia Guide
Pain management
Medical Games
🩺
Doctordle
Medical Wordle -daily word
🚨
Full Code Medical
Run codes & ICU sims
🏥
Prognosis
Real clinical case scenarios
Stay Current
📰
What's New
Practice-changing updates
RoundsRx Licensed Content - Unauthorized Use Prohibited
EMERGENT
Endocrine
ICU
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!)
- Precipitants: infection (30–40% -most common), insulin omission/non-compliance (20–25%), new diagnosis T1DM, MI/ACS, pancreatitis, cocaine, alcohol
Mnemonic -5 I's of DKA Precipitants:
Infection (30–40%, #1 cause -UTI, pneumonia, skin) · Insulin (missed or inadequate doses) · Infarction (MI, stroke, mesenteric ischemia) · Intoxication (cocaine, alcohol, drugs) · Inflammation (pancreatitis, surgery, trauma)
Infection (30–40%, #1 cause -UTI, pneumonia, skin) · Insulin (missed or inadequate doses) · Infarction (MI, stroke, mesenteric ischemia) · Intoxication (cocaine, alcohol, drugs) · Inflammation (pancreatitis, surgery, trauma)
Pathophysiology
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).
Presentation
Symptoms
- Polyuria, polydipsia, nausea, vomiting, abdominal pain
- 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 (serum) -preferred over urine ketones for monitoring
- Urine ketones (if serum BHB unavailable)
- 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
| Parameter | Mild | Moderate | Severe |
|---|---|---|---|
| pH | 7.25–7.30 | 7.00–7.24 | < 7.00 |
| Bicarb (mEq/L) | 15–18 | 10–14 | < 10 |
| Anion Gap | > 10 | > 12 | > 12 |
| Mental Status | Alert | Alert/Drowsy | Stupor/Coma |
🚨 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).
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 -Aggressive Resuscitation
1–1.5 L NS over 1 hour if hypotensive ADA DKA Guidelines, 2023. Then switch to 0.45% or 0.9% NS at 250–500 mL/hr depending on corrected Na⁺. Goal: replace estimated fluid deficit (typically 3–6 L) over 24 hours. LR vs NS: No proven outcome difference in DKA SKALE-DKA, 2024.
1–1.5 L NS over 1 hour if hypotensive ADA DKA Guidelines, 2023. Then switch to 0.45% or 0.9% NS at 250–500 mL/hr depending on corrected Na⁺. Goal: replace estimated fluid deficit (typically 3–6 L) over 24 hours. LR vs NS: No proven outcome difference in DKA SKALE-DKA, 2024.
🔄 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. However, LR contains potassium (4 mEq/L) -avoid if K⁺ >5.5 initially.
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 (no bolus needed per ADA 2026). Target: BG drop of 50–75 mg/dL/hr.
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 (no bolus needed per ADA 2026). 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 ADA guidelines recommend NO bolus -start continuous infusion at 0.14 units/kg/hr directly. 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.
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 (ALL must be met)
- BG < 200 mg/dL
- Anion gap ≤ 12 mEq/L
- Serum bicarbonate ≥ 15 mEq/L
- pH > 7.3
Transitioning to Subcutaneous Insulin
Give SQ long-acting insulin 2 hours before stopping the drip (overlap is mandatory to prevent rebound ketoacidosis) ADA DKA Guidelines, 2026. 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 0.14 units/kg/hr (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 close the gap. |
| Hour 8 | Glucose 190, pH 7.32, bicarb 16, AG 12 (closing). K⁺ 4.0. |
| Hour 10 | AG closed (AG 10), pH 7.38, bicarb 20, patient eating. → Overlap SC insulin (give long-acting + meal dose), wait 2 hours, THEN stop drip. |
Key: Never stop insulin drip until: (1) AG closed, (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.
- Close the gap: Same endpoints — pH > 7.3, bicarb > 18, AG closed. 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⁺ < 3.3 → 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 2: Aggressive IVF — NS 1L/hr. Fluids alone will lower glucose ~50–75 mg/dL/hr.
- Step 3: Once K⁺ ≥ 3.3 → START insulin drip at 0.14 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⁺ < 3.3 = 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 | 0.14 units/kg/hr IV drip (no bolus) OR 0.1 units/kg/hr (with 0.1 units/kg IV bolus) ADA 2026 |
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?
When ALL three criteria are met: BG < 200, AG ≤ 12, bicarb ≥ 15. NOT just when glucose normalizes. And 2 hours after giving long-acting SQ insulin.
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 (CO₂ diffuses into CSF faster than bicarb), 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.
Key findings: HR 118, BP 98/62, RR 28. BG 480, pH 7.12, bicarb 6, AG 28, K⁺ 5.4, BHB 6.8 mmol/L.
Management:
- NS 1L bolus over 1h, then 0.45% NS at 250 mL/hr
- K⁺ 5.4 (>3.5) — start regular insulin drip at 0.1 units/kg/hr (no bolus) ADA, 2023
- 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.
Key findings: BG 185, pH 7.22, bicarb 12, AG 22, BHB 5.2 mmol/L. K⁺ 4.1.
Management:
- Recognize euglycemic DKA — glucose near-normal but AG acidosis with ketones
- Hold SGLT2 inhibitor immediately
- Start insulin drip + D10 infusion (glucose already low, needs dextrose from the start)
- Volume resuscitate aggressively — SGLT2i causes osmotic diuresis
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 anion gap has narrowed to 14, and his bicarb is now 16. We are targeting gap closure before transitioning to subcutaneous insulin. 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
Complications
- Hypokalemia (from insulin shifting K⁺ intracellular)
- Hypoglycemia (from excess insulin or failure to add dextrose)
- Cerebral edema (especially children, rapid fluid shifts)
- ARDS (from aggressive fluid resuscitation)
- Thrombosis (hypercoagulable state)
Before Discharge
- Patient tolerating PO fluids and meals
- On appropriate SQ insulin regimen
- BG < 200, AG closed, K⁺ repleted
- Precipitant identified and addressed
- Diabetes education arranged
- Endocrine follow-up within 1–2 weeks
⚡ Summary
One-Screen Summary
Definition
BG > 250 + pH < 7.3 + bicarb < 18 + anion gap > 10 + ketones. Triad must all be present.
Precipitants
Infection (30–40%), missed insulin (20–25%), new DM, MI, pancreatitis, SGLT2i use
Initial Management
IV NS 1L bolus → check K⁺ → if K⁺ ≥ 3.5 start regular insulin 0.1 u/kg/hr → replace K⁺ in IVF
Key Rule
Add D5 when BG < 250. Stop drip only when AG closed. Overlap SQ insulin 2 hrs before stopping drip.
Biggest Pitfalls
Starting insulin with K⁺ < 3.5. Stopping insulin when BG normalizes (not when AG closes). Missing euglycemic DKA on SGLT2i.
ICU Threshold
pH < 7.0, bicarb < 10, AMS, hemodynamic instability, K⁺ < 3.0 with ECG changes
📄 One Pager
ICU / Endocrine · One Pager
Diabetic Ketoacidosis
Hyperglycemia + anion-gap acidosis + ketones. Fluids first. Check K⁺ before insulin. Close the gap, not just the glucose.
🧪 Diagnosis
- BG > 250 mg/dL
- pH < 7.3 / Bicarb < 18
- Anion gap > 10–12
- Ketones positive (serum BHB preferred)
- 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: 1–1.5L NS over 1h → then 0.45%NS at 250–500 mL/hr
2
Check K⁺ BEFORE insulin -if < 3.5, replace first. Do NOT start insulin.
3
Insulin: Regular insulin 0.1 units/kg/hr IV (no bolus) ADA 2026
4
When BG < 250: Add D5 to IVF, reduce insulin to 0.05 units/kg/hr
5
Stop drip when: BG < 200 + AG ≤ 12 + bicarb ≥ 15 -NOT just BG normal
6
SQ insulin overlap: Give long-acting 2h before stopping drip
💊 Key Drugs
Regular insulin0.1 u/kg/hr
KCl20–40 mEq/hr IV
NS → 0.45%NS250–500 mL/hr
Glargine0.25 u/kg SQ
📊 Monitoring
- BG every 1h (POC)
- BMP q2–4h
- Anion gap q2–4h
- BHB q4h
- UOP ≥ 0.5 mL/kg/hr
⚠️ Pitfalls
- Insulin with K⁺ < 3.5
- Stopping drip at BG normal
- Missing euglycemic DKA
- No SQ overlap
- Missing precipitant
🏥 ICU Threshold
- pH < 7.0 / bicarb < 10
- Altered mental status
- Hemodynamic instability
- K⁺ < 3.0 with ECG changes
🎓 Key Trial
- ADA 2026: No IV insulin bolus -drip only at 0.1 u/kg/hr
- Resolution: Gap closure, not glucose normalisation
- Bicarb: Only if pH < 6.9 (not routine)
Rounds · ICU / Endocrine
Based on ADA Standards of Care 2026 · NEJM Review
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.
Septic Shock: Sepsis + vasopressor requirement to maintain MAP ≥ 65 mmHg + serum lactate > 2 mmol/L despite adequate fluid resuscitation. In-hospital mortality > 40%.
Septic Shock: Sepsis + vasopressor requirement to maintain MAP ≥ 65 mmHg + serum lactate > 2 mmol/L despite adequate fluid resuscitation. In-hospital mortality > 40%.
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.
⚠️ SSC 2026: qSOFA has poor sensitivity -misses too many septic patients. NEWS/MEWS now recommended as primary screening tools.
NEWS / MEWS Calculators -SSC 2026 recommended sepsis screening tools. NEWS ≥7 = emergency. MEWS ≥5 = urgent review.
🧮 Calculate NEWS / MEWS →
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.
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. No preference NS vs balanced. | 30 mL/kg still suggested. Balanced crystalloids now suggested over 0.9% saline (except TBI). New: fluid removal after resuscitation now addressed. |
| Vasopressors | Start via central line | Peripheral vasopressor start now OK -don't delay for central access. NE → vasopressin → epi unchanged. New: BP targets for older adults. |
| Steroids | Suggested if ongoing vasopressor need | Strengthened: hydrocortisone 200 mg/day if vasopressors ≥ 4 hours. Reverses 2016 recommendation against routine steroids. |
| 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). |
| New topics | - | "Code sepsis" huddle protocols. Post-sepsis discharge rehab. Institutional performance improvement programs. 46 entirely new statements (129 total). |
Pathophysiology
Infection triggers innate immune activation → cytokine storm (TNF-α, IL-1, IL-6) → endothelial dysfunction → vasodilation + capillary leak → distributive shock. Simultaneously, microvascular thrombosis + impaired oxygen utilization → end-organ ischemia even when MAP is maintained. This explains why restoring BP alone is insufficient -tissue perfusion and oxygen delivery must be optimized.
Common Sources
- Lung -pneumonia (30–40%, most common)
- Urinary tract -pyelonephritis, urosepsis (20–30%)
- Abdomen -peritonitis, cholangitis, bowel perforation, diverticulitis
- Line/device -CLABSI, endocarditis, infected hardware
- Skin/soft tissue -necrotizing fasciitis, infected wounds
- CNS -meningitis, encephalitis, brain abscess (least common)
- Unknown source -20–30% of sepsis cases (especially in immunocompromised)
Presentation
- Fever > 38.3°C OR hypothermia < 36°C (hypothermia = worse prognosis)
- Tachycardia, tachypnea
- 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
- 30 mL/kg crystalloid bolus if MAP < 65 mmHg OR lactate ≥ 4 mmol/L
- Vasopressors if MAP < 65 despite fluid resuscitation → target MAP ≥ 65
Laboratory Workup
Mandatory
- Lactate -venous or arterial; most critical early test; > 4 = cryptic shock regardless of BP
- Blood cultures × 2 peripheral sets (before antibiotics)
- BMP -creatinine (AKI), glucose, bicarb (metabolic acidosis)
- CBC with differential (leukocytosis, left shift, or leukopenia)
- Procalcitonin -helps guide antibiotic duration (de-escalation at < 0.25)
Targeted by Suspected Source
- UA + urine culture (UTI/urosepsis -2nd most common source)
- Sputum Gram stain + culture, respiratory panel (pneumonia -most common source)
- LFTs, lipase, RUQ ultrasound (abdominal source)
- Coagulation panel (PT/INR, PTT, fibrinogen) -if DIC suspected
- LP (cell count, protein, glucose, Gram stain, culture) if CNS source
- C. diff if recent antibiotics + diarrhea
Imaging
- Bedside echo -cardiac function, IVC collapsibility (volume status), wall motion, pericardial effusion (fastest, most actionable)
- CXR -portable if unstable; pneumonia, pulmonary edema, effusion
- RUQ ultrasound -gallbladder, biliary dilation (cholangitis)
- 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 | ICU, vasopressors even if BP normal, repeat q2h |
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
Resuscitation Strategy
0–15 min -Recognition & Stabilisation
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.
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) | Gram-positives: Strep, MSSA (not MRSA) Gram-negatives: E. coli, Klebsiella, Proteus, Pseudomonas, Enterobacter Anaerobes: Bacteroides, Fusobacterium | ⚠️ Diarrhea, rash, ↑ AKI when paired with vancomycin ACORN, 2024, thrombocytopenia (prolonged use), hypokalemia, C. diff | Default empiric -broadest beta-lactam. Covers gram-negatives + anaerobes. Use when source unknown or intra-abdominal/respiratory suspected. |
| Cefepime (Maxipime) | 2g IV q8h | Gram-positives: Strep, MSSA (not MRSA) Gram-negatives: E. coli, Klebsiella, Pseudomonas, Enterobacter, Serratia, Citrobacter No anaerobes | ⚠️ Neurotoxicity (confusion, myoclonus, seizures -especially in renal failure), rash, C. diff | Alternative to pip-tazo. Better with vanc (↓ AKI vs pip-tazo+vanc). Use when anaerobic coverage not needed. Add metronidazole if anaerobes needed. |
| Meropenem (Merrem) | 1g IV q8h | Gram-positives: Strep, MSSA (not MRSA) Gram-negatives: E. coli, Klebsiella, Pseudomonas, Enterobacter, ESBL-producers, Acinetobacter Anaerobes: Bacteroides | ⚠️ Seizures (less than imipenem), diarrhea, C. diff, rash. ↓ valproic acid levels (contraindicated together) | 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 (worse with pip-tazo), Red Man Syndrome (infuse over ≥ 1h), ototoxicity, DRESS (rare) | 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 (> 14d), serotonin syndrome (weak MAOi -avoid SSRIs/SNRIs/tramadol), lactic acidosis, peripheral neuropathy & optic neuritis (> 28d -may be irreversible), myelosuppression | Alternative to vanc if: CKD/AKI (no renal adjustment), VRE suspected, MRSA pneumonia (superior lung penetration), no IV access (100% PO bioavailability). |
| Metronidazole (Flagyl) | 500 mg IV q8h | Anaerobes: Bacteroides fragilis, Clostridium, Fusobacterium, Prevotella Protozoa: C. diff (PO), Giardia, Entamoeba | ⚠️ Metallic taste, nausea, peripheral neuropathy (prolonged use), disulfiram reaction with alcohol, seizures (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: Pip-tazo or cefepime covers gram-negatives + Pseudomonas. Vancomycin or linezolid covers MRSA. You need BOTH for empiric sepsis coverage. Neither alone is sufficient.
Fluid Resuscitation
30 mL/kg balanced crystalloid (LR or PlasmaLyte preferred over NS) SMART, 2018 SALT-ED, 2018 if MAP < 65 or lactate ≥ 4.
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.
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) if vasopressors required ≥ 4 hours (SSC 2026 threshold -don't wait all day). Shortens shock duration. ADRENAL 2018; APROCCHSS 2018 CORTICUS, 2008.
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) if vasopressors required ≥ 4 hours (SSC 2026 threshold -don't wait all day). Shortens shock duration. ADRENAL 2018; APROCCHSS 2018 CORTICUS, 2008.
🔄 Updated Practice (SSC 2026): Peripheral vasopressor start is now OK -don't delay pressors waiting for central access. Norepinephrine remains first-line (SOAP II -dopamine caused more arrhythmias). Vasopressin second-line (0.03 units/min, fixed). Dopamine and "renal-dose dopamine" are DEBUNKED. New in 2026: BP targets for older adults now specifically addressed (previously one-size-fits-all MAP 65).
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.
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 IBW, 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.
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 | Higher (≥ 75) in chronic hypertension or AKI |
| 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 |
Antibiotic De-Escalation Examples
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 |
|---|---|---|---|---|
| Undifferentiated sepsis | Vanc + Zosyn — covers MRSA + Pseudomonas + GNR + anaerobes | Blood cx: MSSA | Stop both. → Cefazolin 2g IV q8h | Bacteremia: 2–4 weeks |
| Undifferentiated sepsis | Vanc + Zosyn — broadest empiric coverage | Blood cx: MRSA | Stop Zosyn. Continue Vancomycin (AUC-guided) | Min 2 weeks, longer if endocarditis |
| Severe CAP + sepsis | 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 | Vanc + Zosyn — empiric until source confirmed | Urine cx: E. coli (pansensitive) | Stop both. → Ceftriaxone 1g IV daily → PO cipro or TMP-SMX | UTI: 5–7 days. Pyelo: 7–10 days |
| Perforated appendicitis (post-op) | 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 |
| Cellulitis (admitted, severe) | Vanc + Zosyn — concern for MRSA + polymicrobial in severe presentation | Blood cx negative at 48h. No abscess. Non-purulent. | Stop both. → PO cephalexin 500mg q6h. If purulent: TMP-SMX DS BID | 5 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 |
| Fever + tachycardia (unclear source) | Vanc + Zosyn — empiric for possible sepsis | All cx negative at 48h. PCT < 0.25. Improving. | Stop all antibiotics. Consider non-infectious SIRS? | Stop if no infection identified |
| Sepsis + prior ESBL on antibiogram | Meropenem + Vanc — known ESBL colonization requires carbapenem empirically | Blood cx: ESBL E. coli | Stop vanc. Continue meropenem. IV → PO TMP-SMX if susceptible for step-down | 7–14 days (source-dependent) |
| Neutropenic fever | Vanc + Cefepime — cefepime = anti-pseudomonal monotherapy for febrile neutropenia; vanc if line infection suspected | Blood cx: Enterococcus faecalis (ampicillin-susceptible) | Stop both. → Ampicillin 2g IV q4h | 2–4 weeks (rule out endocarditis with TTE/TEE) |
| HAP/VAP | Vanc + Zosyn — hospital-acquired = Pseudomonas + MRSA risk | Sputum: Pseudomonas aeruginosa (susceptible to cefepime) | Stop vanc. Zosyn → Cefepime 2g IV q8h (narrower anti-pseudomonal) | 7 days for HAP/VAP |
| Sepsis + TPN/central line + prior abx | Vanc + Zosyn + Micafungin — Candida risk factors (TPN, lines, broad abx) | Blood cx: Candida albicans (fluconazole-susceptible) | Stop vanc + Zosyn. Micafungin → Fluconazole 400mg IV/PO daily. Remove all central lines. | 14 days from first negative blood cx |
| Necrotizing fasciitis | 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 |
| CAP (standard) | Ceftriaxone + Azithro — standard CAP: typicals + atypicals | Legionella urinary antigen positive | Stop ceftriaxone. Continue Azithromycin 500mg IV/PO daily alone (or levofloxacin) | 5 days (azithro) or 7 days (levo) |
| SBP (cirrhosis + ascites) | Vanc + Zosyn — empiric for undifferentiated peritonitis | Ascitic fluid cx: E. coli. Susceptible to ceftriaxone. | Stop both. → Ceftriaxone 1g IV daily | 5 days. Repeat paracentesis at 48h — PMN should drop > 25%. |
| 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. |
| Neutropenic fever (no source found) | Vanc + Cefepime — standard febrile neutropenia regimen | All cx negative at 72h. ANC recovering (> 500). | Stop antibiotics when afebrile × 48h + ANC > 500 × 2 days | Stop with ANC recovery. |
| Line sepsis (suspected CLABSI) | Vanc + Zosyn — MRSA + GNR coverage for line infection | 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) |
The narrowest effective antibiotic is the best antibiotic.
💊 Medications & Doses
Empiric Antibiotic Selection
| Clinical Scenario | Empiric Regimen | Notes |
|---|---|---|
| Unknown source, community-acquired | Pip-tazo (Zosyn) 3.375g q6h IV (E. coli, Klebsiella, Pseudomonas, Proteus, Bacteroides, MSSA) + Vancomycin (Vancocin) 25–30 mg/kg loading (MRSA, Strep, Enterococcus) | Pip-tazo = gram-negatives + anaerobes + Pseudomonas. Vanc = MRSA. Together = broadest empiric coverage. |
| Recent abx (< 90 days) or recent hospitalization (increased risk of resistant organisms but NOT automatic carbapenem) | Pip-tazo (Zosyn) 3.375g q6h IV + Vancomycin (Vancocin) (same regimen -Zosyn + vanc is still appropriate) | Still start with Zosyn + vanc. This already covers Pseudomonas + MRSA + anaerobes. Consider adding: (1) antifungal (Micafungin (Mycamine) 100mg IV) if prolonged abx + TPN/central line, (2) double Pseudomonas coverage (add Amikacin (Amikin) or Ciprofloxacin (Cipro)) only if severely ill + high local Pseudomonas resistance. Do NOT escalate to meropenem based on these risk factors alone. |
| Known or suspected MDR* organism *MDR = Multi-Drug Resistant (prior ESBL/CRE* culture, known MDR colonization, institutional antibiogram showing >10–20% ESBL prevalence) *CRE = Carbapenem-Resistant Enterobacterales | Meropenem (Merrem) 1g q8h IV (ESBL E. coli, ESBL Klebsiella, Pseudomonas, Acinetobacter, Enterobacter, Bacteroides) + Vancomycin (Vancocin) (MRSA) | ”HCAP” is no longer a category (removed 2019 ATS/IDSA). Meropenem is NOT first-line for most patients. Reserve for known ESBL/CRE colonization or high institutional ESBL rates on antibiogram. Prior abx use or recent hospitalization alone does NOT warrant a carbapenem -Zosyn + vanc covers the vast majority of scenarios. Add micafungin if Candida risk (TPN, prior abx, abdominal surgery). Always check your local antibiogram. |
| CAP (community-acquired pneumonia) | Ceftriaxone (Rocephin) 1–2g IV daily (S. pneumoniae, H. influenzae, Moraxella, E. coli, Klebsiella) + Azithromycin (Zithromax) 500 mg IV/PO (Mycoplasma, Chlamydophila, Legionella) | Ceftriaxone = typical organisms. Azithro = atypicals. Add vanc/linezolid if MRSA risk. Or levofloxacin monotherapy if Legionella risk. |
| Urosepsis (community-acquired) | Ceftriaxone (Rocephin) 1g IV daily (E. coli, Klebsiella, Proteus, Enterobacter) | E. coli is #1 cause of UTI/urosepsis. Adjust based on urine Gram stain + culture. Cipro if quinolone-susceptible. Add ampicillin if Enterococcus on Gram stain. |
| Biliary / abdominal source | Pip-tazo (Zosyn) 3.375g q6h IV (E. coli, Klebsiella, Enterococcus, Bacteroides, Clostridium) OR Ceftriaxone (Rocephin) (gram-negatives) + Metronidazole (Flagyl) 500 mg q8h IV (Bacteroides, Clostridium, Fusobacterium) | Abdominal infections = gram-negatives + anaerobes. Needs urgent source control (ERCP, IR drainage, surgery). |
| Neutropenic fever (ANC < 500) | Cefepime (Maxipime) 2g q8h IV (E. coli, Klebsiella, Pseudomonas, Enterobacter, Serratia, MSSA) ± Vancomycin (Vancocin) (MRSA) | Cefepime = anti-pseudomonal + broad gram-negative. Add vanc if line infection, skin source, or hemodynamically unstable. Add micafungin at day 4–5 if fever persists. |
| Suspected meningitis | Ceftriaxone (Rocephin) 2g q12h IV (S. pneumoniae, N. meningitidis, H. influenzae, E. coli) + Vancomycin (Vancocin) (penicillin-resistant S. pneumoniae) + Dexamethasone (Decadron) 0.15 mg/kg q6h × 4d | Dex before or with first abx dose. Add ampicillin (Listeria monocytogenes) if > 50yo, immunocompromised, or pregnant. |
| Necrotizing fasciitis | Pip-tazo (Zosyn) (gram-negatives, anaerobes) + Vancomycin (Vancocin) (MRSA) + Clindamycin (Cleocin) 900 mg q8h (Group A Strep toxins, S. aureus toxins -50S ribosome inhibitor suppresses toxin production) | Clindamycin = toxin suppression (not for coverage). Surgical emergency -OR for debridement ASAP. Delay = death. |
| Suspected fungal sepsis | Micafungin (Mycamine) 100 mg IV daily (Candida species including C. glabrata, C. krusei) OR Fluconazole (Diflucan) 800 mg load → 400 mg IV daily (Candida albicans, C. tropicalis, C. parapsilosis) | Add if: TPN, prior broad-spectrum abx, abdominal surgery, Candida colonization, persistent fever despite antibiotics. Micafungin preferred empirically (broader Candida coverage). Fluconazole for step-down if C. albicans confirmed susceptible. |
🔄 Updated Practice: Vancomycin monitoring has changed. Old practice: target trough 15–20 mcg/mL. New practice (2020 ASHP/IDSA guidelines): target AUC/MIC 400–600 using Bayesian software or two-level AUC estimation. Trough-based dosing led to unnecessary nephrotoxicity. AUC-guided dosing reduces AKI by ~30%.
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 2008 SSC 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) | Refractory shock on NE > 0.25 mcg/kg/min | 200 mg/day IV (50 mg q6h or continuous) | ADRENAL 2018 -faster shock reversal; no mortality benefit |
| Drotrecogin alfa | - | Withdrawn from market | PROWESS-SHOCK 2012 -no benefit |
📋 On Rounds
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 hours ANDROMEDA-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. (5)
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 0.04 units/min (fixed dose, no titration) — works via V1 receptors, catecholamine-independent VASST, 2008. Step 2: Hydrocortisone 50 mg IV q6h if on pressors ≥ 4 hours 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) if vasopressors required ≥ 4 hours (SSC 2026 — reverses 2016 recommendation against routine steroids). 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). (3)
What empiric antibiotics do you choose for undifferentiated septic shock?
Vancomycin + pip-tazo 4.5g q6h — covers MRSA, Pseudomonas, GNR, and anaerobes. If high AKI risk: use cefepime instead of pip-tazo — pip-tazo inhibits renal tubular secretion of vancomycin → ↑ nephrotoxicity Pip-Tazo AKI Study, 2017. MDR risk or prior resistant organisms → meropenem 1g q8h. Add micafungin if Candida risk (TPN, prior abx, abdominal surgery). SSC 2026: antibiotics within 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 peak PRORATA, 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 suggests albumin as adjunct to crystalloids when patients have received large volumes of crystalloid. SAFE, 2004: no overall benefit vs saline, but sepsis subgroup showed trend toward lower mortality. ALBIOS, 2014: targeting albumin ≥ 3 g/dL did not improve 28-day mortality but improved hemodynamics. Practical use: consider 25% albumin (100 mL)
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.
Key findings: HR 128, RR 32, SpO₂ 88% on 6L NC. Lactate 6.8, WBC 22K, procalcitonin 14.5.
Management:
- Norepinephrine via peripheral IV — do not delay for central line CENSER, 2019
- Pip-tazo 4.5g IV q6h + vancomycin 25 mg/kg load
- NE at 0.3, MAP still 58 — add vasopressin 0.03 u/min VASST, 2008
- Hydrocortisone 50 mg IV q6h (pressors ≥ 4h) ADRENAL, 2018
Antibiotic Stewardship: Day 2 — sputum culture grows S. pneumoniae (pan-sensitive). MRSA nasal swab negative (NPV > 95%). De-escalate: stop vancomycin, narrow pip-tazo → 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 pip-tazo + vancomycin empirically.
Key findings: Admission PCT 8.2. Blood cultures grow pan-sensitive S. pneumoniae. MRSA nasal swab negative. Day 3: PCT 1.4 (83% decline), afebrile x24h.
Management:
- De-escalate vancomycin (MRSA swab negative, NPV > 95%)
- Narrow pip-tazo 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?
- Procalcitonin trend → Falling PCT supports antibiotic cessation PRORATA 2010
- 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
- Sedation/delirium assessment → CAM-ICU, RASS target, daily SAT/SBT
ICU Monitoring
| Parameter | Frequency | Target / Action |
|---|---|---|
| MAP (arterial line) | Continuous | ≥ 65 mmHg; higher if chronic HTN |
| Urine output | Hourly | ≥ 0.5 mL/kg/hr; oliguria = reassess volume + pressors |
| Lactate | q2h until < 2 × 2 | Target clearance ≥ 10%/2h |
| Blood glucose | q1–2h (insulin infusion) | 140–180 mg/dL; avoid < 70 |
| BMP | q6–12h initially | Monitor AKI (creatinine), electrolytes, bicarb |
| CBC | Daily | Thrombocytopenia = DIC; trend WBC |
| Cultures | At 48–72h | 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 IBW, Pplat ≤ 30). Daily SAT + SBT per ABCDEF bundle.
Antibiotic Duration
Standard: 5–7 days for bacteraemia 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 bacteraemia (minimum 14 days from first negative culture).
Certain infections require longer: endocarditis (4–6 weeks), osteomyelitis (6 weeks -oral step-down is acceptable OVIVA, 2019), S. aureus bacteraemia (minimum 14 days from first negative culture).
⚡ Summary
Summary
Definition
Organ dysfunction (SOFA ≥ 2) from infection. Shock = vasopressors + lactate > 2 despite adequate IVF.
1-Hour Bundle
Lactate → blood cultures × 2 → broad-spectrum abx → 30 mL/kg IVF → vasopressors if MAP < 65
Antibiotics
Pip-tazo + vancomycin empirically. Meropenem if MDR risk. Narrow at 48–72h. Duration 5–7 days typically.
Vasopressors
NE first-line. Add vasopressin second (0.03 u/min). Hydrocortisone 200 mg/day if NE > 0.25. Dobutamine only for low CO.
Source Control
Find it. Drain it. Remove the line. Consult surgery. Equal importance to antibiotics. Target < 6–12h.
Mortality Hack
Every hour antibiotic delay in septic shock ≈ +7% mortality. Do not wait for cultures. Culture then treat.
Fluid
LR or PlasmaLyte over NS. 30 mL/kg initial. Stop if no response. Fluid overload kills. Check lactate q2h.
De-escalation
Narrow antibiotics at 48–72h. Use procalcitonin. Stop at 5–7 days if improving. Wean vasopressors by MAP response.
📄 One Pager
ICU · One Pager
Sepsis & Septic Shock
Every hour of antibiotic delay = ~7% more mortality. Cultures → antibiotics → fluids → pressors → source control. Do not delay for imaging.
🔬 Sepsis-3 Definitions
- Sepsis: SOFA ≥ 2 + suspected infection
- Septic shock: Vasopressors + lactate > 2 despite IVF
- qSOFA: AMS + RR ≥ 22 + SBP ≤ 100 (≥ 2 = high risk, screen only)
- 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
- 🫁 Lung -pneumonia (most common)
- 🚿 UTI / urosepsis
- 🫀 Abdomen -cholangitis, peritonitis
- 💉 Line infection / endocarditis
- 🧠 Meningitis (neck stiffness + fever)
⏱️ 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: Pip-tazo + vancomycin (or meropenem if MDR risk). Within 1 hour.
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
6
Source control: Drain abscess, remove line, decompress biliary. Target < 12h.
💉 Vasopressors
Norepinephrine (Levophed)1st line -0.01–3 mcg/kg/min
Vasopressin (Vasostrict)0.03 u/min add-on
Hydrocortisone (Solu-Cortef)200 mg/day if NE > 0.25
Epinephrine (Adrenalin)Refractory only
Dobutamine (Dobutrex)Low CO + adequate MAP
📊 Monitoring Targets
MAP≥ 65 mmHg
UOP≥ 0.5 mL/kg/hr
LactateClear ≥ 10%/2h
Glucose140–180 mg/dL
ScvO₂≥ 70%
⚠️ Pitfalls
- Delaying antibiotics for cultures
- Using dopamine SOAP II, 2010
- NS over balanced crystalloids
- No source control
- Broad abx never narrowed
- Missing hypothermia = bad sign
Rounds · ICU
SSC 2026 · Sepsis-3 2016 · SOAP II 2010 · SMART 2018 · CLOVERS 2023
EmergentICUCardiology
Acute Decompensated Heart Failure
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. |
| Cold & Dry (~5%) | Impaired | No | Cardiogenic shock. Pressors + inotropes + MCS. See Cardiogenic Shock topic. |
| Warm & Dry (~5%) | Adequate | No | Compensated. Optimize oral GDMT. Do NOT over-diurese. Symptom management. |
Presentation & Workup
Symptoms
- Dyspnea, orthopnea, paroxysmal nocturnal dyspnea
- Rapid weight gain (> 2 kg in 48 hrs)
- Leg edema, fatigue, decreased exercise tolerance
Exam
- JVD, S3 gallop, pulmonary crackles, pitting edema
- Elevated JVP = elevated filling pressures (wet)
- Cool extremities, narrow pulse pressure = low output (cold)
Initial Labs & Imaging
| Test | Why |
|---|---|
| BNP / NT-proBNP | Most sensitive. Very high NPV for ruling out HF. BNP > 400 or NT-proBNP > 900 supports ADHF. |
| CXR | Pulmonary vascular congestion, Kerley B lines, cardiomegaly, pleural effusions. Fastest imaging. |
| Echo | Definitive. EF (HFrEF vs HFpEF), wall motion abnormalities, valvular disease, pericardial effusion. |
| BMP | Cr (tracks with diuresis), Na⁺ (hyponatremia = poor prognosis), K⁺, bicarb. |
| Troponin | Rule out ACS as trigger. Demand ischemia common in ADHF. |
| ECG | STEMI trigger? Afib with RVR? New LBBB? |
| CBC, LFTs, TSH | Anemia worsens HF. Congestive hepatopathy. Thyroid disease is reversible cause. |
Common Triggers -What Tipped Them Over?
- Medication non-adherence -most common, especially diuretics and sodium restriction
- Dietary indiscretion -sodium/fluid overload
- ACS / ischemia -always rule out with troponin + ECG
- Afib with RVR -loss of atrial kick + tachycardia-mediated worsening
- Uncontrolled HTN -flash pulmonary edema
- Infection / sepsis -increased metabolic demand on failing heart
- Worsening renal function -impaired diuresis
- Anemia, thyroid disease, PE, medication changes (NSAIDs, CCBs, TZDs)
🚨 Management
Decongestion Strategy (Warm & Wet)
Step 1 -IV Diuresis
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.
Swipe for more examples
📋 Clinical Example -HFrEF GDMT Rapid Initiation
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. Beta-blocker: Carvedilol (Coreg) 3.125mg BID -start low, do NOT uptitrate during acute decompensation. |
| Day 2–3 | ARNI: Sacubitril-valsartan (Entresto) 24/26mg BID -if SBP > 100. 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 | 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). |
| Week 4 | Entresto → 97/103mg BID (target dose), carvedilol → 12.5mg BID. |
| Week 8 | Carvedilol → 25mg BID (target dose). |
Key principles:
- 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.
📋 Clinical Example -Acute Decompensated HF (Wet & Warm)
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 2.5× their home oral dose as IV dose -she takes 40mg PO daily → give 80–100mg IV). 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.
💊 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. |
| Metolazone (Zaroxolyn) ADD-ON | 2.5–5 mg PO 30 min before loop diuretic | Sequential nephron blockade. Overcomes diuretic resistance. | Thiazide-like. Works even at low GFR (unlike HCTZ). Massive electrolyte shifts -monitor K⁺, Mg, Na aggressively. |
| 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). |
| Nitroprusside (Nipride) SPECIALIZED | 0.3–5 mcg/kg/min IV | Afterload + preload reduction. Refractory hypertensive ADHF. | 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 than dobutamine (2–3h). |
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.
| Drug Class | During ADHF | When to Hold |
|---|---|---|
| ACEi / ARB / ARNI* *ARNI = Angiotensin Receptor-Neprilysin Inhibitor (sacubitril-valsartan) | Continue unless hypotensive or AKI | SBP < 90, Cr rising > 30%, K⁺ > 5.5 |
| Beta-blocker | Reduce dose if decompensated. Do NOT stop abruptly. | Cardiogenic shock, symptomatic bradycardia, severe hypotension |
| MRA* (spironolactone) *MRA = Mineralocorticoid Receptor Antagonist (spironolactone, eplerenone) | Continue if K⁺ stable | K⁺ > 5.0, AKI |
| SGLT2i* *SGLT2i = Sodium-Glucose Co-Transporter 2 Inhibitor (dapagliflozin, empagliflozin) | Continue if tolerated. EMPULSE, 2022: empagliflozin started in-hospital ADHF → clinical benefit. | eGFR < 20, DKA risk |
For full chronic GDMT optimization (the four pillars, titration targets, key trials), see Heart Failure (Chronic).
📋 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.
Key findings: JVP 14 cm, bibasilar crackles, 3+ pitting edema. BNP 3,200, Cr 1.6 (baseline 1.2), K⁺ 3.2.
Management:
- IV furosemide 160 mg bolus (2x home oral dose), monitor UOP — target > 200 mL in 2h
- UOP 80 mL in 2h — double to 320 mg IV, add metolazone 5 mg PO 30 min prior
- Continue GDMT: SGLT2i safe in-hospital EMPULSE, 2022
- Replete K⁺ aggressively (target > 4.0), daily weights and strict I/Os
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.
Key findings: MAP 52, narrow pulse pressure, lactate 4.1, Cr 3.2 (baseline 1.4), BNP 8,400. Echo: EF 12%.
Management:
- 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)
- Initiate all 4 GDMT pillars: ARNI + BB + MRA + SGLT2i PARADIGM-HF, 2014
- 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."
Monitoring Parameters -Acute Decompensated Heart Failure
| Parameter | Frequency | Target / Action |
|---|---|---|
| Daily weights | Every morning, same scale, before breakfast | Target 1-2 kg/day net loss during active diuresis. Weight gain > 2 lbs/day = fluid retention → uptitrate diuretics. |
| Strict I&Os | Every shift (q8h tallies) | Net negative 1-2 L/day during active diuresis. UOP ≥ 0.5 mL/kg/hr. If UOP drops, consider diuretic dose increase or combination diuretic therapy. |
| BMP (K⁺, Cr, Na⁺) | Daily while on IV diuretics; q1-2 days after RAAS inhibitor initiation or titration | K⁺ 4.0-5.0 (RAAS inhibitors raise K⁺, diuretics lower it). Cr rise ≤ 0.3 acceptable with diuresis. Na < 130 → consider fluid restriction. |
| Blood pressure | q4-6h inpatient; each clinic visit outpatient | SBP ≥ 90 for ARNI/ACEi/ARB titration. Tolerate asymptomatic SBP 90-100 if on GDMT. Hold vasodilators if symptomatic hypotension. |
| Heart rate | q4-6h inpatient; each visit outpatient | Resting HR 60-70 on maximally tolerated beta-blocker. Do NOT uptitrate BB during active decompensation. |
| BNP / NT-proBNP | Admission and pre-discharge (trend) | > 30% reduction from admission = adequate decongestion. Discharge BNP predicts readmission risk. |
| Echocardiogram (EF) | Reassess at 3-6 months after GDMT optimization | 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.
🧪 Workup
Diagnostic Evaluation — Acute Decompensated Heart Failure
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. |
| TTE (echocardiogram) | Classify HFrEF (EF ≤40%) vs HFpEF (EF ≥50%). Assess wall motion, valves, diastolic function, RVSP. | EF ≤40% = HFrEF. EF 41–49% = HFmrEF. LA dilation, elevated E/e′ suggest elevated filling pressures. |
| BMP | Cr (cardiorenal syndrome), K⁺ (before RAAS inhibitors), Na⁺ (hyponatremia = poor prognosis), bicarb | Cr rise >0.3 from baseline = cardiorenal. Na <135 = independent mortality predictor. |
| CBC | Anemia worsens HF (high-output physiology). Infection as precipitant. | Hgb <10 → evaluate and treat anemia. Leukocytosis → infectious trigger? |
| Iron studies | Iron deficiency (even without anemia) worsens HF outcomes. IV iron improves symptoms. | Ferritin <100 OR ferritin 100–299 + TSAT <20% = iron deficient. Treat with IV iron FAIR-HF, 2009. |
| TSH | Hyper- and hypothyroidism are reversible causes of HF. | Check in all new HF diagnoses. |
| ECG | Ischemia, arrhythmia (new AF), LVH, LBBB (CRT candidacy if QRS ≥150 ms). | LBBB + EF ≤35% + QRS ≥150 ms → strong CRT indication. |
| Troponin | Rule out ACS as trigger for decompensation. Chronic mild elevation common in HF. | Acute rise-and-fall → ACS workup. Chronic low-level elevation = myocardial stress (not necessarily ACS). |
| CXR | Pulmonary edema (cephalization, Kerley B lines, effusions), cardiomegaly. | ~20% of ADHF patients have a normal CXR. Do not rely on CXR alone to rule out HF. |
Always identify the precipitant: Dietary indiscretion, medication non-adherence, new arrhythmia (AF), ACS, infection, uncontrolled HTN, anemia, renal dysfunction, PE, thyroid disease.
⚡ Summary
Summary
First Step
Classify profile: Warm vs Cold / Wet vs Dry. This drives the entire management strategy.
Warm & Wet
IV diuresis at 1–2.5× home dose. Monitor UOP, daily weight, BMP. Add metolazone for diuretic resistance.
Cold & Wet
ICU. Inotropes (dobutamine/milrinone) before aggressive diuresis. May need invasive monitoring.
GDMT
Continue ACEi/ARB/ARNI, beta-blocker (reduce if needed), MRA, SGLT2i. Do not stop without reason.
Discharge Criteria
On oral diuretics, stable on room air, weight at dry weight, no orthopnea, creatinine stable.
Biggest Pitfall
Giving fluids to a patient who is “cold” without recognizing they’re volume overloaded — worsens congestion.
📄 One Pager
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.
🧪 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.
🔍 Overview
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) |
| New LBBB | New or presumably new LBBB in setting of ischemic symptoms → treat as STEMI equivalent (use Sgarbossa criteria if prior LBBB) |
| Posterior MI | ST depression V1–V3 with tall R waves → get posterior leads (V7–V9). ST elevation ≥ 0.5 mm confirms posterior STEMI. |
| De Winter T waves | Upsloping ST depression at J-point with tall symmetric T waves in precordial leads → STEMI equivalent (proximal LAD). |
| Wellens syndrome | Deep symmetric T-wave inversions or biphasic T waves in V2–V3 during pain-free interval → critical LAD stenosis. Will STEMI soon if not intervened on. |
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
STEMI Protocol
0 min -Door
12-lead ECG within 10 minutes. Activate cath lab. ASA 325 mg chewed. Heparin bolus (per cath lab protocol). O₂ only if SpO₂ < 90%. IV access × 2.
🔄 Updated Practice: Old teaching: give supplemental oxygen to all MI patients. Current practice: oxygen only if SpO2 <90%. The DETO2X-AMI, 2017 and AVOID, 2015 showed that routine oxygen in normoxemic MI patients did NOT reduce infarct size and may worsen outcomes through coronary vasoconstriction and increased oxidative stress. Hyperoxia is not benign.
≤ 90 min -Balloon
Primary PCI (percutaneous coronary intervention) is the gold standard. Door-to-balloon target < 90 min. Stent the culprit lesion. STREAM, 2013
If no PCI available
Fibrinolysis within 30 min of first medical contact if PCI not available within 120 min. Tenecteplase (weight-based single IV bolus) or alteplase. Transfer for angiography within 3–24h regardless. STREAM, 2013: pharmacoinvasive strategy (lysis → transfer for PCI) is non-inferior to primary PCI.
Post-PCI
Dual antiplatelet therapy (DAPT): ASA 81 mg daily + P2Y12 inhibitor (ticagrelor 90 mg BID PLATO, 2009 or prasugrel 10 mg daily TRITON-TIMI 38, 2007 preferred over clopidogrel). Duration: 12 months minimum post-ACS DAPT Study, 2014. May shorten to 3–6 months if high bleeding risk TWILIGHT, 2019. High-intensity statin (atorvastatin 80 mg) PROVE IT-TIMI 22, 2004. Beta-blocker within 24h if stable. ACEi/ARB within 24h if anterior MI or EF < 40%.
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. |
💊 Medications
Acute STEMI Medications
| Drug | Dose | Timing | Notes |
|---|---|---|---|
| Aspirin IMMEDIATE | 325 mg chewed (not swallowed) | Immediately on recognition | Chewing provides faster absorption. Continue 81 mg daily indefinitely after. ISIS-2, 1988 |
| Ticagrelor (Brilinta) PREFERRED P2Y12 | 180 mg loading → 90 mg BID | At time of PCI (or sooner) | Preferred over clopidogrel PLATO, 2009: reduced CV death + MI + stroke. Reversible binding. Side effects: dyspnea, bradycardia pauses. Do NOT use with > 100 mg ASA. |
| Prasugrel (Effient) 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) 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) 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 |
| High-intensity statin ALL ACS | Atorvastatin 80 mg or rosuvastatin 40 mg | Within 24h | Start regardless of LDL. Plaque stabilization + anti-inflammatory beyond lipid lowering. Lifelong. PROVE IT–TIMI 22, 2004 |
| Beta-blocker | Metoprolol 12.5–25 mg PO | Within 24h if stable | Avoid if: cardiogenic shock, HR < 60, SBP < 100, decompensated HF, cocaine use, severe reactive airway. |
| ACEi / ARB | Lisinopril 2.5–5 mg or equivalent | Within 24h | 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. |
📋 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). |
| Access site | q15min × 1h, then q1h × 4h post-cath | Check for hematoma, bleeding, pseudoaneurysm. Radial: check radial pulse, hand perfusion. Femoral: check distal pulses, retroperitoneal bleed (back pain, Hgb drop). |
| BMP | Daily × 2-3 days, then post-ACEI initiation | Cr (contrast nephropathy peaks 48-72h post-cath). K⁺ > 4.0 and Mg²⁺ > 2.0 for arrhythmia prevention. |
| DAPT compliance | Daily medication reconciliation | ASA 81 mg daily + P2Y12 inhibitor (ticagrelor 90 BID or prasugrel 10 daily). Minimum 12 months post-DES. Premature DAPT discontinuation = stent thrombosis risk. |
| Echocardiogram | Within 24-48h post-PCI | 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. |
| BMP | Cr (contrast nephropathy risk, ACEI dosing), K⁺ (arrhythmia risk), glucose (stress hyperglycemia). | K⁺ > 4.0 and Mg²⁺ > 2.0 to minimize arrhythmia risk. Cr for contrast load planning. |
| Coagulation (PT/INR, aPTT) | Baseline before heparin. Identify existing anticoagulation. | Needed before heparin bolus in cath lab. |
| Lipid panel | Draw within 24h (acute-phase changes lower LDL after 24-48h). | Start high-intensity statin regardless of LDL. LDL target < 70 (some guidelines < 55). |
| BNP / NT-proBNP | Prognostication. Elevated BNP = higher risk of HF and mortality post-MI. | Guides post-MI HF risk stratification. |
| Echocardiogram | Assess EF, wall motion abnormalities (correlate with culprit vessel), mechanical complications (VSD, papillary muscle rupture, free wall rupture). | 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. |
| Immediate Meds | T+5 min | ASA 325 mg (chewed) + ticagrelor 180 mg PO + heparin 60 U/kg bolus + atorvastatin 80 mg | Chew ASA for rapid absorption. Load P2Y12 inhibitor before cath. Heparin for anticoagulation during PCI. Statin started day 1 regardless of lipid panel. |
| Cath Lab | T+48 min | PCI to LAD: 99% proximal occlusion. Drug-eluting stent (DES) placed. TIMI 3 flow restored. | 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. |
| Troponin #2 | T+3h | hs-cTnI: 12,400 ng/L (> 250× ULN). Rising rapidly. | 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%. |
| Troponin #4 (peak) | T+12h | hs-cTnI: 85,000 ng/L (peak). Begins declining thereafter. | 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. |
| Day 2 | T+24h | Troponin trending down: 42,000 → 18,000 ng/L. Start lisinopril 2.5 mg, uptitrate metoprolol. Cardiac rehab consult. Smoking cessation counseling. | 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. |
| Discharge (Day 3) | ASA 81 mg + ticagrelor 90 BID (DAPT × 12 months). Metoprolol succinate 50 mg daily. Lisinopril 5 mg. Atorvastatin 80 mg. Cardiac rehab. Follow-up in 1 week. | 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. |
| Day 2-3 | Troponin 3,400 → 890 ng/L (steadily declining). Wean fluids. Start low-dose metoprolol if HR tolerates. Start lisinopril 2.5 mg cautiously (monitor BP). | 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. | |
| Discharge (Day 4) | ASA 81 + clopidogrel 75 × 12 months. Metoprolol succinate 25 mg. Lisinopril 2.5 mg. Atorvastatin 80 mg. Strict diabetes management (A1c target < 7). | 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. |
| Immediate | T+5 min | ASA 325 + clopidogrel 600 (avoid ticagrelor in shock -absorption unreliable). Heparin. Activate cath lab. Place arterial line. Start norepinephrine 0.1 mcg/kg/min. | 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. |
| Troponin #2 | T+3h post-PCI | hs-cTnI: 96,000 ng/L. Massive surge post-reperfusion. | 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. |
| Meds | T+8 min | ASA 325 + ticagrelor 180 + heparin + atorvastatin 80. Cath lab activated. | 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. |
| CCU Day 1 | Pain free. Troponin trending down: 6,100 ng/L. TTE: EF 55%, mild posterior/lateral hypokinesis. Mild MR (papillary muscle ischemia). | Good EF because LCx territory is smaller than LAD. Mild MR from posterior papillary muscle -monitor with serial TTE. Usually improves with reperfusion. | |
| Discharge (Day 2) | ASA 81 + ticagrelor 90 BID × 12 months. Metoprolol succinate 25 mg. Atorvastatin 80. Cardiac rehab. No ACEi needed (EF preserved). | 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. |
| Troponin #2 | T+3h | hs-cTnI: 6,800 ng/L. Significant rise confirms infarction. | 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 (Day 3) | ASA 81 + ticagrelor 90 BID × 12 months. Amlodipine 5 mg. Atorvastatin 80. Substance abuse counseling. Psychiatry referral. Social work. | 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
Definition
ST elevation in ≥ 2 contiguous leads (≥ 1mm, or ≥ 2mm in V1-V3) OR new LBBB + ischemic symptoms.
Door-to-Balloon
≤ 90 min at PCI center. Transfer target ≤ 120 min. If > 120 min → fibrinolysis within 30 min.
Immediate Meds
ASA 325 mg chewed + P2Y12 inhibitor (ticagrelor 180 or clopidogrel 600) + heparin + atorvastatin 80.
Post-PCI GDMT
DAPT × 12 months. BB (if EF ↓). ACEi (if EF ≤ 40%). Atorvastatin 80. Cardiac rehab.
Complications
Arrhythmias, cardiogenic shock, mechanical (VSD, papillary rupture, free wall rupture) at day 3-7.
Territory
II/III/aVF = RCA (inferior). V1-V4 = LAD (anterior). I/aVL/V5-V6 = LCx (lateral).
📄 One Pager
STEMI -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.
STEMI -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Telemetry ≥48h, serial troponins, ECG post-PCI, access site checks, BMP daily
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Telemetry ≥48h, serial troponins, ECG post-PCI, access site checks, BMP daily
📣 Present: One-liner + key points → see Rounds tab
Post-STEMI Monitoring Parameters
| Parameter | Frequency | Target / Action |
|---|---|---|
| Continuous telemetry | Minimum 48h post-PCI (longer if EF ≤40%) | Reperfusion arrhythmias: AIVR (benign = successful reperfusion), VT/VF, bradycardia in inferior MI. |
| Serial troponins | q3–6h until peak (typically 12–24h post-PCI) | Peak troponin correlates with infarct size. Re-elevation after decline → stent thrombosis or reinfarction. |
| ECG | Immediately post-PCI, then daily ×2–3 days | ST resolution >50% within 60–90 min = successful reperfusion. New ST changes → stent thrombosis. |
| Access site | q15min ×1h, then q1h ×4h post-cath | Hematoma, bleeding, pseudoaneurysm. Radial: pulse + hand perfusion. Femoral: distal pulses, retroperitoneal bleed (back pain, Hgb drop). |
| BP / HR | q1h ×4h post-cath, then q4h | SBP >90 for ACEi/BB initiation. Hypotension in inferior MI → suspect RV infarct (fluids, avoid NTG). |
| BMP | Daily ×2–3 days + post-ACEi initiation | Cr (contrast nephropathy peaks 48–72h). K⁺ >4.0, Mg²⁺ >2.0 for arrhythmia prevention. |
| Echo | Within 24–48h post-PCI | EF, wall motion, mechanical complications (VSD, papillary muscle rupture, free wall rupture at day 3–7). Repeat at 6–12 wk if EF ≤40%. |
| DAPT compliance | Daily medication reconciliation | ASA 81 mg + P2Y12 inhibitor (ticagrelor 90 BID or prasugrel 10 daily). Minimum 12 months post-DES. Premature stop = stent thrombosis. |
Post-STEMI red flags: Recurrent chest pain (stent thrombosis), new murmur day 3–7 (VSD or papillary rupture), sudden hemodynamic collapse (free wall rupture), unexplained Hgb drop (access site or retroperitoneal bleed).
📄 One Pager
Cardiology · One Pager
STEMI
Time is muscle. Door-to-balloon ≤ 90 min. ASA + P2Y12 + heparin + cath lab. Every minute of delay = more myocardium lost.
🧪 Diagnosis
- ST elevation ≥ 1mm in ≥ 2 contiguous leads (≥ 2mm in V1-V3)
- New LBBB with ischemic symptoms
- Posterior MI: ST depression V1-V3 → get V7-V9
- Troponin may be normal initially -ECG is the decision tool
🚨 Immediate Management
- ASA 325 mg chewed + P2Y12 load (ticagrelor 180 mg)
- Heparin bolus + drip
- Activate cath lab → PCI
- Atorvastatin 80 mg
- Morphine only if refractory pain (may reduce P2Y12 absorption)
🗺️ Territory Mapping
- II, III, aVF = Inferior (RCA)
- V1-V4 = Anterior (LAD)
- I, aVL, V5-V6 = Lateral (LCx)
- V3R, V4R = Right ventricle (check if inferior STEMI)
💊 Key Drugs
ASA325 mg chewed
Ticagrelor180 mg load
Heparin60 U/kg bolus
Atorvastatin80 mg
⚠️ Pitfalls
- Delaying PCI for "stabilization"
- Missing posterior/RV STEMI
- Nitro in RV infarct (preload dependent)
- No DAPT × 12 months post-PCI
RoundsRx · Cardiology · One Pager
ACC/AHA STEMI 2013 · PLATO 2009
URGENTCardiology
NSTEMI / Unstable Angina
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.
🔍 Overview
NSTEMI vs Unstable Angina
| Feature | NSTEMI | Unstable Angina |
|---|---|---|
| Troponin | Elevated (rise and/or fall) | Normal |
| ECG | ST depression, T-wave inversions, or nonspecific (NO ST elevation) | Same -may be normal |
| Pathology | Partial/intermittent occlusion with myocardial necrosis | Partial/intermittent occlusion without necrosis |
| Management | Same initial management. NSTEMI → higher risk → earlier invasive strategy. | 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
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
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)
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) |
| Heart rate | Higher HR = more points (e.g., HR 100 = ~15 pts, HR 150 = ~42 pts) |
| Systolic BP | Inverse -lower SBP = more points (SBP 80 = ~63 pts, SBP 160 = ~12 pts) |
| Creatinine | Higher Cr = more points (renal dysfunction worsens prognosis) |
| Killip class | I (no HF) = 0 pts → IV (cardiogenic shock) = ~64 pts |
| Cardiac arrest at presentation | Yes = +43 pts |
| ST-segment deviation | Yes = +30 pts |
| Elevated cardiac enzymes | Yes = +15 pts |
| GRACE Score | In-Hospital Mortality | Risk Level | Action |
|---|---|---|---|
| ≤ 108 | < 1% | Low | Conservative strategy. Stress test before discharge. |
| 109–140 | 1–3% | Intermediate | Consider angiography within 24–72h based on other features. |
| > 140 | > 3% | High | Early invasive strategy -cath within 24h. |
Killip Classification (used in GRACE):
I -No heart failure signs
II -Rales, S3, elevated JVP (mild HF)
III -Acute pulmonary edema
IV -Cardiogenic shock (SBP < 90, end-organ hypoperfusion)
I -No heart failure signs
II -Rales, S3, elevated JVP (mild HF)
III -Acute pulmonary edema
IV -Cardiogenic shock (SBP < 90, end-organ hypoperfusion)
GRACE > 140 = early invasive within 24h. This is the most important cutoff to know. Higher GRACE = more benefit from early angiography TIMACS, 2009.
🚨 Management
Step-by-Step Management -NSTEMI/UA
1
ABCs + Vitals + IV Access + Continuous Telemetry
12-lead ECG within 10 minutes. Establish 2 large-bore IVs. Continuous cardiac monitoring. Supplemental O₂ only if SpO₂ < 90%.
12-lead ECG within 10 minutes. Establish 2 large-bore IVs. Continuous cardiac monitoring. Supplemental O₂ only if SpO₂ < 90%.
2
Aspirin 325 mg -CHEW immediately ISIS-2, 1988
Do NOT swallow whole -chewing provides faster buccal absorption. Continue 81 mg daily lifelong after.
Do NOT swallow whole -chewing provides faster buccal absorption. Continue 81 mg daily lifelong after.
3
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.
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
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).
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
High-intensity statin -start NOW PROVE 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.
Atorvastatin 80 mg PO (or rosuvastatin 40 mg). Start regardless of LDL -plaque stabilization + anti-inflammatory effects beyond lipid lowering. Lifelong.
6
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.
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.
7
Risk stratify -TIMI + HEART + GRACE + serial troponins
TIMI score Quick 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 score ED 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 score Most 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.
TIMI score Quick 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 score ED 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 score Most 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.
8
Decide: Invasive vs Conservative Strategy TIMACS, 2009
GRACE > 140 or high-risk features → Early invasive (cath within 24h)
Intermediate risk → Delayed invasive (cath within 24–72h)
Low risk (HEART 0–3, negative troponins) → Conservative. Stress test if needed.
GRACE > 140 or high-risk features → Early invasive (cath within 24h)
Intermediate risk → Delayed invasive (cath within 24–72h)
Low risk (HEART 0–3, negative troponins) → Conservative. Stress test if needed.
9
P2Y12 inhibitor -timing depends on strategy PLATO, 2009 TRITON-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).
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).
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
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 ACS confirmed
• Cath -within 2h if hemodynamically unstable (treat like STEMI)
• Aspirin -give IMMEDIATELY on recognition
• ECG -within 10 minutes
• Heparin -start as soon as ACS confirmed
• Cath -within 2h if hemodynamically unstable (treat like STEMI)
Invasive vs Conservative Strategy
| Strategy | Who | Timing | Notes |
|---|---|---|---|
| Immediate invasive (< 2h) | Refractory angina, hemodynamic instability, VT/VF, acute HF | Emergent cath | This is essentially a STEMI-equivalent presentation without ST elevation. |
| Early invasive (≤ 24h) | HEART ≥ 7, GRACE > 140, rising troponin, new ST changes, diabetes | Cath within 24h | TIMACS, 2009: early (< 24h) vs delayed (> 36h) → reduced refractory ischemia in high-risk patients. |
| Delayed invasive (24–72h) | Intermediate risk (HEART 4–6) | Cath within 72h | Acceptable for stable patients. Load P2Y12 when anatomy known (cath lab). |
| Conservative / ischemia-guided | Low risk (HEART 0–3), no recurrent symptoms, negative serial troponins | Stress test if needed | Medical management. Cath only if stress test positive or recurrent symptoms. |
P2Y12 timing in NSTEMI: If going to early cath → load in the cath lab once coronary anatomy is known (in case CABG is needed -clopidogrel/ticagrelor delay surgery 5–7 days). If conservative strategy → load upfront.
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 over PCI for complex anatomy SYNTAX, 2009
• Diabetics with multivessel CAD: CABG beats PCI FREEDOM, 2012
• Stable CAD: PCI does NOT beat optimal medical therapy on hard outcomes COURAGE, 2007
• Multivessel/left-main: CABG preferred over PCI for complex anatomy SYNTAX, 2009
• Diabetics with multivessel CAD: CABG beats PCI FREEDOM, 2012
📋 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 CABG SYNTAX, 2009 FREEDOM, 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.
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.
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.
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. |
| Chest pain assessment | q4h nursing assessment + PRN | Recurrent chest pain → repeat ECG, consider NTG, notify cardiology. Refractory pain = indication for urgent cath. |
| BP | q4h (q1h if on NTG drip or hemodynamically unstable) | SBP ≥ 90 for beta-blocker and ACEi initiation. Hold NTG if SBP < 90. Target HR 60-70 with beta-blocker. |
| HR | q4h; continuous on telemetry | Tachycardia > 100 → pain? anxiety? HF? bleeding? Bradycardia < 50 → hold BB, check for conduction disease. |
| aPTT (if on heparin drip) | q6h until therapeutic, then q12h | Goal aPTT 60-80 seconds (1.5-2.5× control). Adjust per institutional heparin nomogram. |
| BMP | Daily; post-cath (contrast nephropathy) | 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). | 0-3 = low risk (1.7% MACE, consider discharge). 4-6 = moderate (12% MACE, admit). 7-10 = high (65% MACE, early invasive). |
| TIMI risk score | Predicts 14-day MACE in NSTEMI/UA. Guides invasive vs conservative strategy. | Score 0-2 = low risk. 3-4 = intermediate. 5-7 = high risk → early invasive strategy (cath within 24h). |
| TTE (echocardiogram) | Assess EF, regional wall motion abnormalities (correlate with ischemic territory), valvular disease. | New RWMA supports ACS. EF ≤ 40% → ACEI/ARB + aldosterone antagonist post-MI. Assess for mechanical complications. |
| CBC | Baseline Hgb for bleeding risk, platelets for DAPT safety. | Anemia may contribute to demand ischemia (Type 2 MI). Thrombocytopenia limits antiplatelet options. |
| BMP | Cr for contrast and medication dosing, K⁺/Mg²⁺ for arrhythmia risk. | Adjust heparin dosing for renal function. K⁺ > 4.0, Mg²⁺ > 2.0. |
| Coags, lipid panel | 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. |
| P2Y12 inhibitor | Ticagrelor (Brilinta) 180 mg load → 90 mg BID PREFERRED Clopidogrel (Plavix) 600 mg load → 75 mg daily Prasugrel (Effient) 60 mg load → 10 mg daily (post-PCI only) | 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. |
| Anticoagulation | Heparin (UFH) 60 U/kg bolus (max 4000 U) → 12 U/kg/hr (max 1000 U/hr) OR Enoxaparin 1 mg/kg SC q12h | 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. |
| Statin | Atorvastatin (Lipitor) 80 mg daily PREFERRED OR Rosuvastatin 40 mg daily | High-intensity statin for ALL ACS regardless of baseline LDL. Start in-hospital. Do not check LDL to decide -just start it. |
| ACEi / ARB | Lisinopril 2.5-5 mg daily (start low) OR Losartan 25-50 mg daily if ACEi intolerant | Indicated if EF ≤ 40%, anterior MI, diabetes, or HTN. Start within 24h if hemodynamically stable (SBP ≥ 90). Continue indefinitely. |
| Nitroglycerin | NTG 0.4 mg SL q5min × 3 PRN chest pain NTG drip 5-200 mcg/min for refractory pain | 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
Definition
Troponin rise + fall with ≥ 1 value > 99th percentile + ischemic symptoms or ECG changes. No ST elevation.
Risk Stratify
GRACE score > 140 → early invasive (cath within 24h). Low risk → conservative strategy with stress test.
Anticoagulation
Heparin drip or enoxaparin. Don't switch between types. Stop after PCI unless other indication.
DAPT
ASA + P2Y12 inhibitor (ticagrelor preferred). Duration: 12 months post-PCI, 1-3 months if high bleed risk.
When to Cath
Recurrent angina, hemodynamic instability, high GRACE, dynamic ST changes, elevated troponin, EF < 40%.
Discharge
Atorvastatin 80 4S, 1994, DAPT PLATO, 2009, BB, ACEi if indicated. Smoking cessation. Cardiac rehab referral.
📄 One Pager
NSTEMI / Unstable Angina -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.
NSTEMI / UNSTABLE ANGINA -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
Cardiology · One Pager
NSTEMI / Unstable Angina
Troponin rise + ischemic symptoms. Risk stratify with GRACE. High risk → early invasive. Low risk → conservative + stress test.
🧪 Diagnosis
- Troponin rise + fall with ≥ 1 value > 99th percentile
- Ischemic symptoms or ECG changes (ST depression, TWI)
- UA = same presentation but troponin negative
- GRACE score determines invasive vs conservative strategy
🚨 Management
- ASA 325 + P2Y12 load + heparin drip
- GRACE > 140 → cath within 24h (early invasive)
- Low GRACE → conservative: medical therapy + stress test
- Atorvastatin 80 mg, BB if no contraindication
⚠️ High-Risk Features
- Dynamic ST changes
- Recurrent angina despite medical therapy
- Hemodynamic instability
- Elevated troponin trending up
- EF < 40% on echo
- Diabetes, CKD, prior PCI/CABG
💊 Key Drugs
ASA325 mg → 81 mg daily
Ticagrelor180 mg load → 90 BID
Heparin60 U/kg bolus → drip
Atorvastatin80 mg daily
⚠️ Pitfalls
- Switching heparin types (increases bleeding)
- Missing Wellens or de Winter pattern
- Not risk-stratifying with GRACE
- Discharging without follow-up plan
RoundsRx · Cardiology · One Pager
ACC/AHA NSTE-ACS 2014 · TIMACS 2009
UrgentCardiology
Arrhythmias
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:
SVT
VT vs SVT
Flutter
Sinus Tachy
MAT
Junctional
Long QT
Brugada
WPW
PACs/PVCs
Sick Sinus
🔍 Overview
Tachycardia Classification
| Width | Regularity | Likely Rhythm | First-Line Treatment |
|---|---|---|---|
| Narrow (< 120 ms) | Regular | AVNRT (~60%), AVRT (~30%), atrial tachycardia (~10%) | Vagal maneuvers → adenosine 6 mg → 12 mg → 12 mg |
| Narrow | Irregular | Afib, Aflutter with variable block, MAT | See Afib topic. MAT → treat underlying (COPD, hypoxia, Mg/K). |
| Wide (> 120 ms) | Regular | VT until proven otherwise. Also: SVT with aberrancy, pre-excited tachycardia. | Treat as VT. Stable → amiodarone. Unstable → cardioversion. Pulseless → defibrillate. |
| Wide | Irregular | 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.
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. | ❌ Mixed precordial directions (typical R-wave progression). |
| Northwest axis | ✅ 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.
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.
| Common Causes | Clue |
|---|---|
| Pain / Anxiety | Most common in hospital. Treat the pain. |
| Hypovolemia / Hemorrhage | Tachycardia + hypotension → fluid resuscitate, check Hgb |
| Fever / Infection / Sepsis | HR rises ~10 bpm per 1°F. Look for source. |
| Pulmonary Embolism | Acute onset + hypoxia + pleuritic pain → CT angiogram |
| Hyperthyroidism | Check TSH if persistent without clear cause |
| Anemia | Compensatory tachycardia. Check CBC. |
| Withdrawal | Alcohol, benzodiazepines, opioids |
| Medications | Albuterol, theophylline, stimulants, anticholinergics |
Multifocal Atrial Tachycardia (MAT)
- ≥ 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.
| Type | Cause | Key Features |
|---|---|---|
| Acquired (most common) | Drugs (see table below), electrolyte abnormalities (hypoK, hypoMg, hypoCa), bradycardia, hypothermia, structural heart disease | Reversible -stop offending agent, correct electrolytes |
| Congenital -LQT1 | KCNQ1 mutation (K⁺ channel) | Events triggered by exercise (especially swimming). Beta-blockers effective. |
| Congenital -LQT2 | KCNH2 (hERG) mutation (K⁺ channel) | Events triggered by auditory stimuli (alarm clock, phone). Beta-blockers + avoid triggers. |
| Congenital -LQT3 | SCN5A mutation (Na⁺ channel) | Events at rest/sleep. Beta-blockers less effective. May need ICD + mexiletine. |
⚠️ Common QTc-Prolonging Drugs
| Category | Drugs |
|---|---|
| Antiarrhythmics | Amiodarone, sotalol, dofetilide, procainamide, quinidine, ibutilide |
| Antibiotics | Fluoroquinolones (levofloxacin, moxifloxacin), macrolides (azithromycin, erythromycin), TMP-SMX |
| Antifungals | Fluconazole, voriconazole |
| Antipsychotics | Haloperidol, quetiapine, ziprasidone, chlorpromazine |
| Antiemetics | Ondansetron (IV doses > 16 mg), droperidol |
| Antidepressants | Citalopram, escitalopram (dose-dependent), TCAs |
| Other | Methadone, hydroxychloroquine, sumatriptan |
⚠️ 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.
- 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.
- 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.
- Definition: SA node dysfunction causing alternating bradycardia (sinus bradycardia, sinus pauses, sinoatrial exit block) and tachycardia (paroxysmal Afib, atrial flutter, atrial tachycardia).
- 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.
Wolff-Parkinson-White (WPW) -Expanded
⚠️ 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.
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. | Benign if: < 10% burden, structurally normal heart, asymptomatic. ⚠️ Concern if: > 10–15% burden (PVC-induced cardiomyopathy), R-on-T phenomenon, post-MI. |
| Aberrancy Clue | 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. |
Sick Sinus Syndrome (Tachy-Brady Syndrome)
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 |
| Electrolytes | Daily | K⁺ > 4.0, Mg²⁺ > 2.0 (low levels promote arrhythmia) |
🚨 Management
SVT -Acute Management
Step 1 -Vagal
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 IV ACC/AHA/HRS SVT Guidelines, 2015. Or synchronized cardioversion (50–100J biphasic) if unstable or refractory to all drugs.
Ventricular Tachycardia
| Presentation | Treatment |
|---|---|
| Pulseless VT | Defibrillate (unsynchronized) 120–200J biphasic. Start CPR. Follow ACLS arrest protocol. |
| Unstable VT with pulse | 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.
Name 5 drugs that prolong the QT interval.
Common QT-prolonging drugs: (1) Sotalol (Class III antiarrhythmic), (2) Haloperidol (antipsychotic -especially IV), (3) Fluoroquinolones (levofloxacin, moxifloxacin), (4) Ondansetron (IV doses > 16 mg), (5) Methadone. Also: amiodarone, dofetilide, procainamide, azithromycin, erythromycin, citalopram, quetiapine, droperidol, fluconazole. Check crediblemeds.org for a complete list.
What is Brugada syndrome and what triggers VF?
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 (1991)
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%).
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).
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.
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 -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. |
| Symptoms | Each visit | Pleuritic chest pain, dyspnea, positional symptoms. Worsening = consider effusion enlargement or recurrence. |
| Renal function (Cr) | 1-2 weeks after starting NSAIDs | NSAID nephrotoxicity. Check BMP especially in elderly, CKD, heart failure, or concurrent ACEi/ARB. |
| Activity restriction | Until CRP normal + asymptomatic | Non-athletes: restrict until symptom resolution. Athletes: no competitive sports for minimum 3 months (6 months if myopericarditis). |
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 |
| Electrolytes | Daily | K⁺ > 4.0, Mg²⁺ > 2.0 (low levels promote arrhythmia) |
🧪 Workup
Diagnostic Evaluation -SVT
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.
| Class | MOA | Drugs | Clinical Use | ⚠️ Side Effects |
|---|---|---|---|---|
| Ia Na⁺ channel block (intermediate) | Blocks Na⁺ channels + K⁺ channels → slows conduction + prolongs repolarization. Widens QRS and prolongs QT. | Procainamide (Pronestyl) Quinidine Disopyramide (Norpace) | VT, SVT, Afib, WPW (procainamide). Brugada VF storm (quinidine). | ⚠️ Procainamide: drug-induced lupus (chronic use), QT prolongation → Torsades, agranulocytosis ⚠️ Quinidine: cinchonism (tinnitus, HA, vision changes), diarrhea, thrombocytopenia, QT prolongation |
| Ib Na⁺ channel block (fast) | Blocks Na⁺ channels with fast kinetics → shortens repolarization. Works preferentially on ischemic/depolarized tissue. | Lidocaine (Xylocaine) Mexiletine (Mexitil) | VT/VF (acute, especially ischemia-related). Mexiletine for congenital LQT3. Lidocaine for refractory VF in ACLS. | ⚠️ Lidocaine: CNS toxicity (seizures, confusion, perioral numbness, tremor), bradycardia ⚠️ Mexiletine: GI upset, tremor, dizziness |
| Ic Na⁺ channel block (slow) | Potent Na⁺ channel blockade with slow kinetics → markedly slows conduction. Minimal effect on repolarization. | Flecainide (Tambocor) Propafenone (Rythmol) | Afib/flutter (rhythm control) -"pill-in-pocket" for paroxysmal Afib. SVT. Only in structurally normal hearts. | ⚠️ CAST trial: increased mortality 3.6× post-MI CAST, 1991 ⚠️ Contraindicated in structural heart disease, CAD, HF ⚠️ Proarrhythmic (can organize Afib → flutter with 1:1 conduction → always co-prescribe AV nodal blocker) |
| II Beta-blockers | Block β₁-adrenergic receptors → decrease SA node automaticity, slow AV conduction, reduce myocardial O₂ demand. | Metoprolol (Lopressor) Esmolol (Brevibloc) (ultra-short acting) Atenolol (Tenormin) Propranolol (Inderal) | Rate control (Afib, SVT, sinus tachycardia). Suppress PVCs. Congenital long QT (LQT1, LQT2). Post-MI arrhythmia prevention. | ⚠️ Bradycardia, hypotension, bronchospasm (non-selective), fatigue, depression, mask hypoglycemia in diabetics ⚠️ Do NOT stop abruptly -rebound tachycardia/hypertension |
| III K⁺ channel blockers | Block K⁺ channels → prolong repolarization (action potential duration) → prolong QT interval. | Amiodarone (Cordarone) Sotalol (Betapace) Dofetilide (Tikosyn) Ibutilide (Corvert) | Amiodarone: VT, VF, Afib, almost any arrhythmia (Swiss army knife). Sotalol: Afib, VT. Dofetilide: Afib maintenance. Ibutilide: acute Afib/flutter conversion. | ⚠️ Amiodarone (multiple organ toxicity): pulmonary fibrosis, thyroid dysfunction (hypo & hyper -contains iodine), hepatotoxicity, corneal microdeposits, peripheral neuropathy, blue-gray skin, photosensitivity, QT prolongation ⚠️ Sotalol: QT prolongation → Torsades, bradycardia (also has Class II activity) ⚠️ Dofetilide: must be initiated inpatient (3-day telemetry) -QT prolongation risk. Renally dosed. ⚠️ Ibutilide: QT prolongation → Torsades (monitor 4–6h post-infusion) |
| IV Ca²⁺ channel blockers (non-DHP) | Block L-type Ca²⁺ channels in SA/AV node → slow AV conduction and decrease heart rate. | Diltiazem (Cardizem) Verapamil (Calan) | Rate control (Afib, SVT). Acute SVT termination. AVNRT/AVRT (second-line after adenosine). | ⚠️ Hypotension, bradycardia, constipation (verapamil), peripheral edema ⚠️ NEVER in WPW + Afib (enhances accessory pathway conduction → VF) ⚠️ NEVER in decompensated HF (negative inotropy worsens failure) ⚠️ Avoid with beta-blockers IV (additive AV block risk) |
Other Key Antiarrhythmic Agents
| Drug | MOA | Clinical Use | ⚠️ Side Effects |
|---|---|---|---|
| Adenosine (Adenocard) | Activates A₁ adenosine receptors → transient AV node block (6-second half-life) | First-line for stable narrow-complex SVT (AVNRT/AVRT). Diagnostic (unmasks underlying rhythm). 6 mg → 12 mg → 12 mg rapid IV push. | ⚠️ 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
Definition
Narrow complex regular tachycardia (HR 150-250). Most common: AVNRT > AVRT > atrial tachycardia.
First Move
Modified Valsalva (blow into syringe 15s → lie flat + leg raise). 43% conversion rate REVERT, 2015.
Adenosine
6 mg rapid IV push → flush. If no effect → 12 mg. Warn patient about chest tightness. Contraindicated in WPW + Afib.
WPW Warning
Delta wave on baseline ECG = accessory pathway. Do NOT give AV nodal blockers → VF risk. Use procainamide.
Unstable
Synchronized cardioversion 50-100J. Don't waste time with meds if hypotensive or altered.
Long-Term
Recurrent SVT → EP referral for catheter ablation (cure rate > 95% for AVNRT). Pill-in-pocket BB/CCB for rare episodes.
📄 One Pager
One Pager -Arrhythmias
SVT -AT A GLANCE
📋 Diagnose: Narrow QRS tachycardia (rate 150–250). Regular R-R.
🧪 Workup: 12-lead ECG, BMP (K⁺, Mg²⁺), TSH, trop if chest pain
⚡ Treat: Vagal → adenosine → cardioversion if unstable
💊 Maintenance: Metoprolol, diltiazem, or flecainide/sotalol for recurrent
📈 Monitor: Telemetry, ECG post-conversion, electrolytes
📣 Present: See Rounds tab
🧪 Workup: 12-lead ECG, BMP (K⁺, Mg²⁺), TSH, trop if chest pain
⚡ Treat: Vagal → adenosine → cardioversion if unstable
💊 Maintenance: Metoprolol, diltiazem, or flecainide/sotalol for recurrent
📈 Monitor: Telemetry, ECG post-conversion, electrolytes
📣 Present: See Rounds tab
📄 One Pager
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
RoundsRx · Cardiology · One Pager
ACC/AHA SVT 2015 · REVERT 2015
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
- Pericardial friction rub -scratchy, 3-component (best heard with diaphragm, patient leaning forward)
- Diffuse ST elevation with PR depression (concave-up, diffuse -NOT territorial like STEMI)
- New or worsening pericardial effusion on echo
Pericarditis vs STEMI on ECG
| Feature | Pericarditis | STEMI |
|---|---|---|
| ST elevation | Diffuse, concave-up ("smiley face") | Territorial (matches coronary distribution), convex-up |
| PR segment | PR depression (except aVR -PR elevation) | Usually normal |
| Reciprocal changes | None (except aVR) | Present (ST depression in opposite leads) |
| Q waves | Absent | May develop |
| T-wave evolution | ST normalizes BEFORE T inversions | T inversions occur WITH persistent ST elevation |
Cardiac Tamponade
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, 2011: 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. |
| Symptoms | Each visit | Pleuritic chest pain, dyspnea, positional symptoms. Worsening = consider effusion enlargement or recurrence. |
| Renal function (Cr) | 1-2 weeks after starting NSAIDs | NSAID nephrotoxicity. Check BMP especially in elderly, CKD, heart failure, or concurrent ACEi/ARB. |
| Activity restriction | Until CRP normal + asymptomatic | Non-athletes: restrict until symptom resolution. Athletes: no competitive sports for minimum 3 months (6 months if myopericarditis). |
🧪 Workup
Workup -Pericarditis & Pericardial Disease
| Test | Findings | Clinical Significance |
|---|---|---|
| 12-lead ECG | Diffuse ST elevation (concave up), PR depression, Spodick sign (downsloping TP segment) | Stage I changes present in ~80%. Diffuse = not in a coronary territory (distinguishes from STEMI). |
| TTE (Echocardiogram) | Pericardial effusion size, tamponade physiology (RA/RV collapse, IVC plethora, respiratory variation) | Assess effusion size and hemodynamic impact. Repeat in 1-2 weeks to monitor resolution. |
| Troponin | Elevated if myopericarditis | Mild elevation suggests myocardial involvement. Does NOT change treatment but restricts activity longer. |
| CRP / ESR | Elevated (CRP often markedly) | CRP guides treatment duration -continue colchicine + NSAIDs until CRP normalizes. |
| CBC | Leukocytosis (if infectious/inflammatory) | WBC differential helps distinguish viral (lymphocytic) vs bacterial (neutrophilic). |
| BMP | Cr (baseline), electrolytes | Baseline renal function before NSAID therapy. Monitor during treatment. |
| Blood cultures | If infectious etiology suspected | Obtain if febrile, immunocompromised, or subacute presentation suggesting bacterial/TB pericarditis. |
Diagnosis requires 2 of 4: (1) pleuritic chest pain, (2) pericardial friction rub, (3) diffuse ST elevation + PR depression, (4) new/worsening pericardial effusion.
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
Diagnosis
Need 2 of 4: pleuritic chest pain, pericardial rub, diffuse ST elevation + PR depression, new pericardial effusion.
Treatment
Ibuprofen 600 TID × 2 weeks + colchicine 0.5 BID × 3 months. Colchicine halves recurrence [COPE, ICAP].
Tamponade
Beck's triad (hypotension + JVD + muffled sounds). Pulsus paradoxus > 10. RV collapse on echo. → Pericardiocentesis.
Avoid
Anticoagulation (risk of hemorrhagic pericardial effusion). Steroids first-line (high recurrence rate).
Myopericarditis
Pericarditis + troponin elevation. Avoid exercise until CRP normalizes and symptoms resolve × 3 months.
Recurrence
Restart colchicine × 6 months. Consider IVIG or anakinra (IL-1 blocker) for refractory cases.
📄 One Pager
Cardiology · One Pager
Acute Pericarditis
Pleuritic chest pain + diffuse ST elevation + PR depression. NSAIDs + colchicine. Always rule out tamponade. Avoid anticoagulation.
🧪 Diagnosis -Need 2 of 4
- Pleuritic chest pain (sharp, worse lying flat, better leaning forward)
- Pericardial friction rub
- Diffuse ST elevation + PR depression on ECG
- New or worsening pericardial effusion on echo
🚨 Management
- Ibuprofen 600 mg TID × 2 weeks (taper over weeks)
- Colchicine 0.5 mg BID × 3 months (halves recurrence) [COPE, ICAP]
- Activity restriction until CRP normalizes + symptoms resolve
- Myopericarditis (troponin ↑): no exercise × 3-6 months
⚠️ Tamponade -Recognize Early
- Beck's triad: hypotension + JVD + muffled heart sounds
- Pulsus paradoxus > 10 mmHg
- Echo: RV diastolic collapse (most specific), IVC plethora
- Treatment: emergent pericardiocentesis (echo-guided)
💊 Key Drugs
Ibuprofen600 mg TID × 2wk
Colchicine0.5 mg BID × 3mo
AcetaminophenPRN adjunct
AvoidAnticoagulation, steroids first-line
⚠️ Pitfalls
- Missing tamponade
- Using steroids first-line (high recurrence)
- Anticoagulation → hemorrhagic effusion
- Not adding colchicine from day 1
- Confusing with STEMI on ECG
RoundsRx · Cardiology · One Pager
ESC Pericardial Diseases 2015 · COPE · ICAP 2011
EMERGENTCardiology
Aortic Dissection
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)
- Stroke symptoms (carotid involvement), ACS/STEMI (coronary involvement), paraplegia (spinal artery), mesenteric ischemia, AKI (renal artery)
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
- Ascending aorta replacement ± aortic valve repair/replacement ± coronary reimplantation
- 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 2013 ADSORB, 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.
- Neuro checks q1-2h -carotid extension (stroke, altered mental status).
- Distal pulses q2-4h -bilateral radial, femoral, DP. New deficit = malperfusion.
- Serial CTA -if conservative management. 48-72h, then 1-2 weeks, 1/3/6/12 months.
🧪 Workup
Diagnostic Evaluation -Aortic Dissection
Time-critical diagnosis. Type A dissection mortality increases 1-2% per hour without surgery. Do NOT delay imaging for labs.
| Test | Findings | Clinical Significance |
|---|---|---|
| CTA chest/abdomen/pelvis GOLD STANDARD | Intimal flap, true/false lumen, extent of dissection, branch vessel involvement | Sensitivity >95%. Defines Stanford type (A vs B), extent, malperfusion. Get full aorta (chest through pelvis). |
| CXR | Widened mediastinum (>8 cm), abnormal aortic contour, left pleural effusion | Insensitive (~60%) but may be first clue. Normal CXR does NOT rule out dissection. |
| Type & Screen | - | Prepare for potential emergent surgery. Crossmatch if Type A. |
| CBC | H/H for baseline | Serial Hgb to monitor for hemorrhage. Leukocytosis common (stress response). |
| BMP | Cr (baseline), electrolytes | Renal function -renal artery malperfusion? Baseline before contrast. |
| Coags (PT/INR, aPTT) | Baseline coagulation | Pre-surgical assessment. DIC can develop with extensive dissection. |
| Troponin | May be elevated | Coronary malperfusion (Type A extending into coronary ostia → STEMI mimic). Also consider concurrent ACS. |
| Lactate | Elevated if malperfusion | Mesenteric ischemia, limb ischemia, shock. Rising lactate = urgent surgical indication. |
💊 Medications
Key Medications -Aortic Dissection
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.
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Esmolol (Brevibloc) 1ST LINE -HR | 500 mcg/kg bolus, then 50-200 mcg/kg/min drip | IV | Target HR <60 bpm FIRST. Ultra-short half-life (9 min) -easily titratable. Preferred initial agent. |
| Nicardipine (Cardene) ADD FOR BP | 5-15 mg/hr IV drip | IV | 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.
Malperfusion
Stroke (carotid), MI (coronary), bowel ischemia (mesenteric), renal failure (renal), limb ischemia (iliac).
📄 One Pager
Aortic Dissection -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.
AORTIC DISSECTION -AT A GLANCE
📋 Classify: Stanford A (ascending = surgery) vs B (descending = medical). DeBakey I/II/III.
🧪 Workup: CTA chest/abdomen/pelvis (gold standard). Type & screen, CBC, BMP, troponin, lactate.
⚡ Treat: HR <60 FIRST (esmolol), THEN SBP <120 (nicardipine). Type A = emergent surgery.
💊 Drugs: Esmolol drip → nicardipine. Labetalol alternative. NEVER vasodilate without BB.
📈 Monitor: A-line, HR q5-15min, UOP hourly, neuro checks, serial CTA if Type B.
🚨 Malperfusion: Stroke, MI, bowel ischemia, renal failure, limb ischemia = surgical emergency.
🧪 Workup: CTA chest/abdomen/pelvis (gold standard). Type & screen, CBC, BMP, troponin, lactate.
⚡ Treat: HR <60 FIRST (esmolol), THEN SBP <120 (nicardipine). Type A = emergent surgery.
💊 Drugs: Esmolol drip → nicardipine. Labetalol alternative. NEVER vasodilate without BB.
📈 Monitor: A-line, HR q5-15min, UOP hourly, neuro checks, serial CTA if Type B.
🚨 Malperfusion: Stroke, MI, bowel ischemia, renal failure, limb ischemia = surgical emergency.
🧪 Workup
Workup -Aortic Dissection
- CTA chest/abdomen/pelvis -gold standard. Defines Stanford type, extent, branch involvement. Sensitivity >95%.
- Type & Screen -prepare for emergent surgery (Type A). Crossmatch 4-6 units pRBCs.
- CBC, BMP, coags -baseline H/H, renal function, electrolytes, PT/INR/aPTT
- Troponin -coronary malperfusion (Type A into coronary ostia). MI mimic.
- Lactate -mesenteric malperfusion, shock. Rising lactate = surgical urgency.
- CXR -widened mediastinum (>8 cm), but insensitive (~60%). Normal CXR does NOT rule out dissection.
- D-dimer -highly sensitive negative predictor. If <500 ng/mL, dissection very unlikely (NPV >95%).
💊 Medications
Medications -Aortic Dissection
Beta-blocker FIRST. Target HR <60, then SBP <120. Never vasodilate without beta-blockade.
- Esmolol (Brevibloc) -500 mcg/kg bolus then 50-200 mcg/kg/min drip. Ultra-short acting, highly titratable.
- Nicardipine (Cardene) -5-15 mg/hr IV. Add AFTER BB for SBP control.
- Labetalol (Trandate) -20 mg IV bolus then 1-2 mg/min drip. Combined alpha/beta blocker alternative.
- Pain control: IV morphine 2-4 mg q5-15min PRN. Pain drives sympathetic surge.
📌 Summary
Summary -Aortic Dissection
Type A
Ascending aorta = SURGICAL EMERGENCY. Mortality 1-2%/hr untreated. CT surgery stat.
Type B
Descending only = medical management. HR <60 + SBP 100-120. Surgery only if complicated.
First Move
Esmolol drip for HR <60 FIRST, then nicardipine for SBP <120. Never vasodilate without BB.
Malperfusion
Stroke, MI, bowel ischemia, renal failure, limb ischemia. Any malperfusion = surgical indication.
📄 One Pager
Cardiology / Vascular · One Pager
Aortic Dissection
Tearing pain + BP differential + unequal pulses. Type A = surgery NOW. Type B = HR < 60 + SBP 100-120. BB before vasodilators.
🧪 Classification
- Stanford Type A: ascending aorta involved → SURGICAL EMERGENCY
- Stanford Type B: descending only (distal to L subclavian) → medical management
- DeBakey I: ascending + descending. II: ascending only. III: descending only
- Mortality: Type A = 1-2%/hour without surgery
🚨 Immediate Management
- Esmolol IV first (BB before vasodilator)
- Target HR < 60, then SBP 100-120
- Add nicardipine AFTER HR controlled
- Type A → CT surgery emergently
- Type B → ICU, medical management, serial imaging
⚠️ Malperfusion Syndromes
- Stroke (carotid dissection)
- MI (coronary ostia involvement)
- Mesenteric ischemia (celiac/SMA)
- Renal failure (renal artery)
- Limb ischemia (iliac)
- Spinal cord ischemia (artery of Adamkiewicz)
💊 Key Drugs
Esmolol500 mcg/kg bolus → 50-200 drip
Nicardipine5-15 mg/hr drip
Labetalol20 mg IV → drip alternative
PainIV morphine/fentanyl
⚠️ Pitfalls
- Vasodilator before BB (reflex tachy worsens dissection)
- Delaying CTA for other workup
- Missing Type A -always scan the ascending aorta
- Thrombolytics for "STEMI" that is actually dissection
RoundsRx · Cardiology / Vascular · One Pager
ACC/AHA Aortic Disease 2022 · ESC 2014
EmergentCardiologyID
Infective Endocarditis
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 |
| Fever ≥ 38°C |
| Vascular phenomena: septic emboli, mycotic aneurysm, Janeway lesions, conjunctival hemorrhage |
| Immunologic phenomena: Osler nodes, Roth spots, glomerulonephritis, positive RF |
| 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. |
| Enterococcus | ~10% | GI/GU source. Elderly patients. Requires synergistic therapy (ampicillin + gentamicin or ampicillin + ceftriaxone). |
| Coagulase-negative staph | ~10% | Prosthetic valve IE (especially early < 1 year). S. epidermidis. |
| HACEK organisms | ~3% | Gram-negative, slow-growing. May need prolonged incubation. Treat with ceftriaxone. |
| Culture-negative | ~5–10% | Prior antibiotics (most common reason), Coxiella burnetii (Q fever), Bartonella, Brucella, fungi. |
🚨 Management
Empiric Antibiotic Therapy
| Setting | Empiric Regimen | Notes |
|---|---|---|
| Native valve, acute | Vancomycin (Vancocin) 15–20 mg/kg IV q8–12h + cefepime (Maxipime) 2g IV q8h | Covers MRSA + gram-negatives. Narrow based on cultures. Duration: 4–6 weeks. |
| Native valve, subacute | Vancomycin (Vancocin) + ceftriaxone (Rocephin) 2g IV q24h | Covers strep + staph. Add gentamicin if Enterococcus suspected. Enterococcal Endocarditis Trial, 2013 |
| Prosthetic valve | Vancomycin (Vancocin) + gentamicin + rifampin (Rifadin) 300 mg PO q8h | Rifampin for biofilm penetration. Triple therapy × 6 weeks minimum. Gentamicin × 2 weeks only. |
| IVDU (right-sided) | 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
- Uncontrolled infection -persistent bacteremia > 5–7 days despite appropriate antibiotics, perivalvular abscess, fistula
- 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
- Emergent surgical referral: PVE + paravalvular abscess + heart failure = absolute surgical indication
- 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.
Management:
- Culture-negative workup: Bartonella, Coxiella (Q fever), Brucella, HACEK serologies, Tropheryma whipplei PCR
- 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 |
| Vancomycin trough | Before 4th dose, then 1-2x/week | AUC/MIC-guided dosing preferred. Target AUC 400-600 |
| Gentamicin levels | Peak and trough with first dose | Peak 3-5 mcg/mL (synergy). Trough < 1. Monitor Cr and hearing |
| Renal function | 2-3x/week | 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. |
| TTE → TEE | Vegetations, abscess, valve perforation, regurgitation | Start with TTE. If negative but suspicion high → TEE (sensitivity 90-100% vs TTE ~60-75%). TEE mandatory for prosthetic valves. |
| CBC | Leukocytosis, anemia (chronic disease), thrombocytopenia | 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 | Pending cultures | Covers MRSA + streptococci + HACEK. Add gentamicin if considering enterococcal coverage. |
| MSSA -native valve | Nafcillin or Oxacillin 2g IV q4h | 6 weeks | 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.
Empiric Abx
Vancomycin + ceftriaxone (native valve). Vancomycin + gentamicin + rifampin (prosthetic valve). ID consult always.
Duration
Native valve: 4-6 weeks IV. MSSA TV in IVDU: may shorten to 2 weeks if uncomplicated.
Surgery
HF from valvular dysfunction, uncontrolled infection, large vegetation (> 10mm) with embolism, abscess.
Must Do
Blood cultures × 3 sets from different sites. TTE first → TEE if negative but suspicion high. CT head if neurologic symptoms.
Source
IVDU = tricuspid. Dental = strep viridans. GI/GU = enterococcus. Prosthetic = coag-neg staph early, S. aureus late.
📄 One Pager
Infective Endocarditis -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.
INFECTIVE ENDOCARDITIS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup
Diagnostic Workup
- Blood cultures × 3 sets from separate sites BEFORE antibiotics. 20 mL per set (10 mL aerobic + 10 mL anaerobic). Sensitivity > 90% with 3 sets
- CBC: Leukocytosis, anemia (normocytic, chronic disease), thrombocytopenia (if DIC)
- BMP: Cr (renal emboli, drug-induced nephritis), electrolytes
- 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).
💊 Medications
Antibiotic Therapy
| Organism | Native Valve | Prosthetic Valve | Duration |
|---|---|---|---|
| Empiric (acute) | Vancomycin + cefepime (or gentamicin) | Vancomycin + cefepime + rifampin | Until cultures return |
| MSSA | Nafcillin/oxacillin 2g IV q4h | Nafcillin + rifampin 300mg PO q8h + gentamicin × 2 weeks | NV: 6 weeks. PV: ≥ 6 weeks |
| MRSA | 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
Blood Cultures
3 sets from separate sites BEFORE antibiotics. Repeat q24-48h until clearance documented.
Duke Criteria
2 major OR 1 major + 3 minor OR 5 minor = definite IE. Blood cultures + echo findings are major criteria.
Echo
TTE first (sensitivity 75%). TEE if: prosthetic valve, negative TTE + high suspicion, or suspected abscess (sensitivity 95%).
Treatment Duration
Native valve: 4-6 weeks IV. Prosthetic valve: ≥ 6 weeks. Bactericidal agents only. ID consult for all.
Surgical Indications
Heart failure from valve dysfunction, uncontrolled infection/abscess, large vegetation (> 10mm) with embolic events, prosthetic valve dehiscence.
Complications
Embolic stroke (20-40%), mycotic aneurysm, splenic abscess, renal infarct, new heart block = abscess.
📄 One Pager
Cardiology / ID · One Pager
Infective Endocarditis
Blood cultures × 3 → empiric abx → echo → ID consult → 4-6 weeks IV. Surgery if HF, uncontrolled infection, or large vegetation.
🧪 Modified Duke Criteria
- 2 major = definite IE
- 1 major + 3 minor = definite IE
- Major: typical organism on ≥ 2 cultures; vegetation/abscess on echo
- Minor: predisposing condition, fever, vascular/immunologic phenomena, positive cultures not meeting major
🚨 Management
- Blood cultures × 3 from different sites BEFORE antibiotics
- Empiric: vancomycin + ceftriaxone (native valve)
- Prosthetic valve: vancomycin + gentamicin + rifampin
- TTE first → TEE if negative but high suspicion
- ID consult always. Duration: 4-6 weeks IV
🔪 Surgical Indications
- Heart failure from valvular dysfunction (most common indication)
- Uncontrolled infection (persistent bacteremia > 7 days, abscess)
- Large vegetation > 10mm with embolism EASE, 2012
- Prosthetic valve IE with any of the above
- Fungal endocarditis (almost always requires surgery)
💊 Key Drugs
Vancomycin15-20 mg/kg q8-12h
Ceftriaxone2g IV q12h
Nafcillin2g IV q4h (MSSA)
Gentamicin1 mg/kg q8h (PVE)
⚠️ Pitfalls
- Antibiotics before blood cultures
- Missing perivalvular abscess (need TEE)
- Not consulting surgery early enough
- Not checking for embolic complications (CT head, spleen)
RoundsRx · Cardiology / ID · One Pager
AHA IE Guidelines 2015 · EASE 2012
CardiologyChronic/Acute
Valvular Heart Disease
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:
AS
MR
AR
MS
TR
Murmurs
Echo
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.
Mitral Regurgitation
| Feature | Acute MR | Chronic MR |
|---|---|---|
| Cause | Papillary muscle rupture (post-MI), chordae rupture, endocarditis | Mitral valve prolapse (#1), rheumatic disease, annular dilation from LV dilation |
| LV size | Normal (no time to dilate) | Dilated (volume overload compensated) |
| LA size | Normal → pulmonary edema (no compliance) | Dilated (accommodates regurgitant volume) |
| Murmur | May be soft or absent (equalization of pressures) | Holosystolic at apex, radiates to axilla |
| Treatment | Emergent surgery. Afterload reduction (nitroprusside, IABP) as bridge. | Surgery when: symptomatic, or asymptomatic with EF ≤ 60% or LVESD ≥ 40 mm. MitraClip for high surgical risk. |
Aortic Regurgitation
| Feature | Acute AR | Chronic AR |
|---|---|---|
| Cause | Endocarditis (valve destruction), aortic dissection, trauma | Bicuspid aortic valve, rheumatic disease, aortic root dilation (Marfan, HTN) |
| LV response | Normal size → cannot accommodate volume → pulmonary edema | Eccentric hypertrophy (LV dilation -"cor bovinum") |
| Pulse pressure | May be narrow (LV can't compensate) | 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 |
| Primary causes | Endocarditis (IVDU -right-sided), Ebstein anomaly, carcinoid, rheumatic, pacemaker leads |
| Murmur | Holosystolic at LLSB. ↑ with inspiration (Carvallo sign) -increased RV venous return augments regurgitant flow |
| Exam findings | Elevated JVP with prominent CV waves, pulsatile liver, peripheral edema, ascites |
| Treatment | 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. (3)
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)
- Inotropes (dobutamine) if cardiogenic shock
- Avoid increasing afterload (phenylephrine, vasopressin) — worsens regurgitation
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.
| Test | Purpose | When to Order |
|---|---|---|
| TTE (transthoracic echo) | Valve area, gradients, regurgitation severity, EF, chamber dimensions | All suspected valvular disease. First-line imaging. |
| TEE (transesophageal echo) | Superior visualization of mitral valve, prosthetic valves, endocarditis vegetations, LA thrombus | Prosthetic valve evaluation, pre-surgical planning, suspected endocarditis with negative TTE, pre-cardioversion in AF with valvular disease |
| ECG | LVH (voltage criteria in AS), atrial fibrillation (common in MS, MR), conduction abnormalities | All patients -baseline and with any symptom change |
| BNP / NT-proBNP | Assess hemodynamic burden, detect subclinical decompensation | Baseline and trending with symptom changes. Helps time intervention in asymptomatic severe disease. |
| Exercise stress test | Unmask symptoms in "asymptomatic" severe AS or MR. Assess functional capacity and hemodynamic response. | Asymptomatic severe valve disease when surgery timing is uncertain. Contraindicated in symptomatic severe AS. |
| Cardiac catheterization | Coronary anatomy pre-operatively, hemodynamic assessment when echo is discordant | Pre-surgical evaluation (assess CAD), discrepant echo findings |
Monitoring and Follow-Up
| Setting | Monitoring | Purpose |
|---|---|---|
| Inpatient (high risk) | Continuous telemetry | Detect arrhythmias (VT, pauses, heart block). Minimum 24-48h |
| Holter monitor | 24-48h outpatient | Frequent symptoms (> 1/week). Captures rhythm during symptoms |
| Event monitor | 2-4 weeks outpatient | Less frequent symptoms. Patient-activated during episodes |
| Implantable loop recorder | Up to 3 years | Recurrent unexplained syncope. Gold standard for infrequent events. ISSUE-3 |
| Orthostatic vitals | At follow-up visits | Confirm response to treatment. SBP drop > 20 or DBP > 10 within 3 min of standing |
| Driving restrictions | Counsel at discharge | Varies by state/country. Generally no driving for weeks to months after cardiac syncope |
💊 Medications
Key Medications -Valvular Heart Disease
Mechanical valves require warfarin ONLY. DOACs are contraindicated -dabigatran caused increased thromboembolic events and bleeding in mechanical valves RE-ALIGN, 2013.
| Indication | Drug | Dose / Target | Notes |
|---|---|---|---|
| Mechanical valve anticoagulation | Warfarin (Coumadin) | Target INR 2.5–3.5 (mitral) or 2.0–3.0 (aortic bileaflet) | Warfarin ONLY. DOACs contraindicated [RE-ALIGN]. Lifelong therapy. Add ASA 81mg for additional protection. |
| AF with valvular disease (MS or mechanical valve) | Warfarin (Coumadin) | Target INR 2.0–3.0 | Warfarin, NOT DOACs. "Valvular AF" = moderate-severe MS or mechanical valve. All other AF with valve disease can use DOACs. |
| Volume overload / congestion | Furosemide (Lasix) | 20–80 mg PO/IV daily, titrate to symptoms | Diuretics for symptom relief in any valve lesion with congestion. Caution in severe AS -avoid excessive preload reduction. |
| Afterload reduction (regurgitant lesions) | ACEi/ARB (e.g., lisinopril, losartan) | Standard dosing, titrate to BP | Beneficial in chronic MR and AR with LV dysfunction or HTN. Reduces regurgitant volume. Avoid vasodilators in severe AS. |
| Rate control (MS with AF) | Beta-blockers or CCBs | Metoprolol 25–100mg BID or diltiazem 30–60mg TID | Slowing HR increases diastolic filling time -critical in MS. Avoid tachycardia. |
Endocarditis Prophylaxis
Prophylaxis indications (dental procedures involving gingival manipulation or perforation):
- Prosthetic heart valve (mechanical or bioprosthetic)
- Prior infective endocarditis
- Unrepaired cyanotic CHD (including palliative shunts/conduits)
- Cardiac transplant with valvulopathy
- Drug: Amoxicillin 2g PO 30–60 min before procedure. If PCN allergy: clindamycin 600mg PO or azithromycin 500mg PO.
⚡ Summary
Summary
Severe AS
AVA < 1.0 cm², mean gradient > 40, Vmax > 4 m/s. Symptoms = exertional dyspnea, syncope, angina.
AS Treatment
Symptomatic severe AS → TAVR or SAVR. No medical therapy stops progression. Avoid vasodilators, cautious diuresis.
Severe MR
Acute (papillary rupture): emergent surgery. Chronic: surgery when EF ≤ 60% or LVESD ≥ 40mm, or symptomatic.
Low-Flow AS
Low EF → low gradient despite severe AS. Dobutamine stress echo: AVA stays < 1.0 = truly severe. AVA improves = pseudo-severe.
Anticoag
Mechanical valve = warfarin (lifelong, INR 2.5-3.5 for mitral, 2.0-3.0 for aortic). DOACs contraindicated [RE-ALIGN].
Murmur Tip
Crescendo-decrescendo at RUSB radiating to carotids = AS. Holosystolic at apex radiating to axilla = MR.
📄 One Pager
Valvular Heart Disease -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.
VALVULAR HEART DISEASE -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
Cardiology · One Pager
Valvular Heart Disease
Severe AS = AVA < 1.0 + symptoms → TAVR/SAVR. Severe MR = surgery when EF ≤ 60% or LVESD ≥ 40mm. Don't delay intervention.
🧪 Severe Aortic Stenosis
- AVA < 1.0 cm², mean gradient > 40 mmHg, Vmax > 4 m/s
- Symptoms: exertional dyspnea, syncope, angina
- Once symptomatic → 2-year survival ~50% without intervention
- Low-flow low-gradient: dobutamine stress echo to differentiate true vs pseudo-severe
🚨 When to Intervene
- Symptomatic severe AS → TAVR or SAVR (no medical therapy works)
- Asymptomatic severe AS + EF < 50% → surgery
- Severe MR → surgery when EF ≤ 60% or LVESD ≥ 40mm
- Acute severe MR (papillary rupture) → emergent surgery
💊 Anticoagulation
- Mechanical valve = warfarin lifelong (DOACs contraindicated [RE-ALIGN])
- INR target: 2.5-3.5 (mitral), 2.0-3.0 (aortic)
- Bioprosthetic: warfarin × 3-6 months → then ASA only
- TAVR: DAPT × 3-6 months → then ASA
💊 Key Drugs
No medical Rx for ASValve replacement is the only treatment
Avoid in ASVasodilators, aggressive diuresis
MR afterload reductionACEi for chronic MR
WarfarinMechanical valves only
⚠️ Pitfalls
- Vasodilators in severe AS (fixed obstruction → hypotension)
- DOACs with mechanical valve [RE-ALIGN increased events]
- Missing low-flow low-gradient AS (gradient looks mild)
- Delaying surgery in asymptomatic severe with declining EF
CommonCardiology
Syncope
Transient loss of consciousness with spontaneous recovery due to global cerebral hypoperfusion. The #1 question: is this cardiac or benign? Risk-stratify to determine who goes home vs who gets telemetry.
🔍 Overview
Etiology
| Category | % of Syncope | Examples | Risk |
|---|---|---|---|
| Reflex / vasovagal | ~50–60% | Emotional trigger, prolonged standing, pain, micturition, carotid sinus hypersensitivity | Benign. Prodrome (lightheadedness, warmth, diaphoresis, nausea). |
| Orthostatic hypotension | ~15% | Volume depletion, medications (antihypertensives, diuretics), autonomic neuropathy (diabetes, Parkinson) | Low. SBP drop ≥ 20 or DBP ≥ 10 within 3 min of standing. |
| Cardiac -arrhythmic | ~10–15% | Bradycardia (sick sinus, heart block), VT, SVT, long QT, Brugada, channelopathies | HIGH. Sudden onset without prodrome. Exertional syncope. Family history of SCD. |
| Cardiac -structural | ~5% | Severe AS, HCM (LVOT obstruction), massive PE, cardiac tamponade, aortic dissection | HIGH. Exertional syncope, new murmur, dyspnea. |
| Neurologic | Rare (< 5%) | Vertebrobasilar TIA, subclavian steal. Seizure is NOT syncope (different mechanism). | Variable. True neurologic syncope is rare -most "neurologic" syncope is actually cardiac. |
High-Risk Features -Admit These Patients
If ANY of these are present → admit for telemetry + further workup:
- Exertional syncope -cardiac until proven otherwise (AS, HCM, arrhythmia)
- Syncope while supine or seated -eliminates orthostatic/vasovagal
- No prodrome -sudden LOC without warning suggests arrhythmia
- Abnormal ECG: long QT, Brugada pattern, heart block, new LBBB, delta wave (WPW)
- Family history of sudden cardiac death (especially < 50 yo)
- Known structural heart disease (HF, prior MI, EF < 35%)
- Associated chest pain, dyspnea, or palpitations
- Significant injury from the fall
🧪 Workup
Initial Workup -All Syncope
| Test | Why |
|---|---|
| ECG MANDATORY | EVERY syncope patient gets an ECG. Look for: long QT, short QT, Brugada, WPW (delta wave), heart block, prior MI (Q waves), HCM (LVH + septal Q waves), arrhythmia. |
| Orthostatic vitals | Lying → sitting → standing. SBP drop ≥ 20 or DBP ≥ 10 or HR rise > 30 = positive. |
| BMP, CBC, glucose | Dehydration, anemia, hypoglycemia (not true syncope but a mimic). |
| Troponin | If ACS suspected or exertional syncope. |
| Echo | If structural heart disease suspected (new murmur, exertional syncope, abnormal ECG). Identifies AS, HCM, RV strain (PE), effusion. |
| Telemetry / Holter / Loop recorder | If arrhythmic cause suspected. Telemetry inpatient. Holter for 24–48h. Implantable loop recorder (ILR) for recurrent unexplained syncope. ISSUE-3, Brignole 2012 |
Routine head CT, EEG, and carotid US are NOT indicated for syncope unless focal neurologic signs are present. Syncope ≠ seizure. Syncope ≠ stroke. Over-ordering these wastes resources.
Canadian Syncope Risk Score
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
📋 On Rounds
Why is exertional syncope a red flag?
Exercise increases myocardial oxygen demand and cardiac output requirements. If there's a fixed obstruction (severe AS, HCM with LVOT obstruction), the heart cannot increase CO to match demand → BP drops → cerebral hypoperfusion → syncope. In arrhythmic causes, exercise triggers catecholamine-mediated arrhythmias (VT in ARVC, polymorphic VT in CPVT, long QT).
When is head CT indicated in syncope?
Almost never for syncope itself. Syncope is caused by transient global cerebral hypoperfusion -not a structural brain lesion. Head CT is indicated if: (1) significant head trauma from the fall (especially on anticoagulation), (2) focal neurologic deficits suggesting stroke (but stroke rarely presents as pure syncope), (3) concern for SAH (thunderclap headache). Routine head CT in simple syncope has an extremely low diagnostic yield (< 2%)
What high-risk features on ECG should make you admit a syncope patient?
Admit and monitor if any of: (1) Brugada pattern (coved ST elevation V1-V3), (2) Long QT (QTc > 500), (3) Short QT (QTc < 340), (4) Epsilon waves or TWI V1-V3 (ARVC), (5) WPW (delta wave + short PR), (6) New bundle branch block, (7) Mobitz II or 3rd degree AV block, (8) ST elevation (STEMI), (9) Non-sustained VT on telemetry.
A 22-year-old collapses during basketball and is resuscitated. What do you screen for?
Sudden cardiac arrest in a young athlete = mandatory structural/electrical workup: (1) Echo: HCM (septal thickness ≥ 15 mm), ARVC (RV dilation/dysfunction), dilated cardiomyopathy, anomalous coronary arteries. (2) ECG: WPW, long QT, Brugada, ARVC (epsilon waves, TWI V1-V3). (3) Cardiac MRI: definitive for ARVC (fatty infiltration, fibrosis), myocarditis, scar. (4) Genetic testing if channelopathy suspected. (5)
Clinical Examples
📋 Case 1 — Vasovagal Syncope in a Young Patient
Patient: 22F, no PMH, witnessed syncopal episode while standing in church. Felt warm, lightheaded, and nauseated before losing consciousness for ~10 seconds. No seizure activity, no tongue biting.
Key findings: Exam normal. ECG: normal sinus rhythm, PR 160 ms, QTc 410 ms, no Brugada pattern. Orthostatic vitals: supine 118/72 HR 68 → standing 92/58 HR 102 (positive). Troponin negative. CBC, BMP normal.
Management:
- Low-risk by Canadian Syncope Risk Score — safe for discharge
- Classic vasovagal: prodrome (warmth, nausea), upright posture trigger, brief LOC with rapid recovery
- Counseling: increase fluid intake (2-3 L/day), increase salt (≥ 6g/day), counter-pressure maneuvers (leg crossing, hand grip)
- Avoid prolonged standing, dehydration, and known triggers
- No medications needed for first-episode vasovagal syncope
Teaching point: Vasovagal syncope is the most common cause of syncope (~40%). The classic prodrome (warmth, diaphoresis, nausea, tunnel vision) followed by brief LOC with rapid recovery is diagnostic. ECG is the only mandatory test — routine head CT has < 2% yield and is not indicated without head trauma or focal deficits.
📋 Case 2 — Cardiac Syncope from Complete Heart Block
Patient: 78M, HTN and prior MI, presents after sudden LOC without warning while sitting in his chair. Wife witnessed 15-second LOC with pallor. No prodrome, no postictal state.
Key findings: HR 34, BP 98/60. ECG: complete (3rd degree) AV block with ventricular escape rhythm at 32 bpm. Wide QRS escape complexes. No P-wave/QRS relationship (AV dissociation). Troponin mildly elevated.
Management:
- Admit to telemetry/ICU, transcutaneous pacer pads on standby
- Atropine 0.5-1 mg IV (may not work in infranodal block with wide escape)
- Isoproterenol drip or temporary transvenous pacemaker if hemodynamically unstable
- Permanent pacemaker (dual-chamber DDD) — Class I indication for symptomatic CHB
- Echo to assess structural heart disease; hold AV-nodal blocking agents
Teaching point: Syncope without prodrome ("no warning") while sitting or supine is cardiac until proven otherwise. Red flags: exertional syncope, syncope while supine/seated, family history of sudden cardiac death < 50, structural heart disease. Complete heart block requires a pacemaker regardless of symptoms.
📋 Case 3 — Exertional Syncope in a Young Athlete
Patient: 17M, previously healthy, collapses during basketball practice. Brief LOC with rapid recovery. Teammate says he "just dropped" mid-sprint. No prodrome.
Key findings: Grade III/VI harsh crescendo-decrescendo systolic murmur at LLSB that increases with Valsalva and standing. ECG: LVH with deep Q waves in lateral leads, T-wave inversions. Echo: septal thickness 22 mm, LVOT gradient 45 mmHg at rest (increases to 80 mmHg with Valsalva).
Management:
- Immediate disqualification from competitive sports
- Hypertrophic cardiomyopathy (HCM) with dynamic LVOT obstruction confirmed
- ICD evaluation — exertional syncope in HCM is a major risk factor for sudden cardiac death
- Start beta-blocker (metoprolol) or verapamil for symptom control
- Screen all first-degree relatives (autosomal dominant inheritance)
- Avoid dehydration, vasodilators, and high-intensity exertion
Teaching point: HCM is the most common cause of sudden cardiac death in young athletes in the US. The murmur of HCM is unique: it increases with maneuvers that decrease preload (Valsalva, standing) because reduced LV volume worsens LVOT obstruction. All other murmurs decrease with these maneuvers. Exertional syncope in a young person mandates full structural and electrical cardiac workup.
📣 Sample Presentation
One-Liner
"Ms. Nguyen is a 22-year-old presenting after witnessed syncope at church. She felt lightheaded and warm before losing consciousness for ~10 seconds with no seizure activity. ECG normal sinus, no Brugada, no long QT. Orthostatic positive."
Key Points to Cover on Rounds
Classic vasovagal prodrome (warmth, lightheadedness, standing). Witnessed brief LOC, no seizure activity, rapid return to baseline. ECG: normal sinus, PR normal, QTc 420. Troponin negative. Orthostatic: supine 112/70→standing 88/58 with symptoms. No high-risk features (no exertional, no supine, no FH SCD, no structural heart disease). Plan: discharge with reassurance, hydration, leg crossing techniques, return precautions.
Monitoring and Follow-Up
| Setting | Monitoring | Purpose |
|---|---|---|
| Inpatient (high risk) | Continuous telemetry | Detect arrhythmias (VT, pauses, heart block). Minimum 24-48h |
| Holter monitor | 24-48h outpatient | Frequent symptoms (> 1/week). Captures rhythm during symptoms |
| Event monitor | 2-4 weeks outpatient | Less frequent symptoms. Patient-activated during episodes |
| Implantable loop recorder | Up to 3 years | Recurrent unexplained syncope. Gold standard for infrequent events. ISSUE-3 |
| Orthostatic vitals | At follow-up visits | Confirm response to treatment. SBP drop > 20 or DBP > 10 within 3 min of standing |
| Driving restrictions | Counsel at discharge | Varies by state/country. Generally no driving for weeks to months after cardiac syncope |
⚡ Management
Management by Etiology
| Type | Management |
|---|---|
| Vasovagal | Reassurance and education. Counter-pressure maneuvers (leg crossing, hand grip, squatting). Increase fluid/salt intake (2-3 L/day, 6-10 g salt). Avoid triggers. Tilt training for recurrent episodes |
| Orthostatic | Review and stop offending meds (diuretics, alpha-blockers, vasodilators). Compression stockings. Increase fluids/salt. Rise slowly. Midodrine 2.5-10 mg TID if refractory. Fludrocortisone 0.1-0.2 mg daily |
| Cardiac arrhythmia | Bradycardia (SSS, CHB, Mobitz II) → pacemaker. VT → ICD. WPW → ablation. Long QT → avoid QT-prolonging drugs, beta-blocker, consider ICD |
| Structural cardiac | Aortic stenosis → valve replacement. HCM → avoid dehydration/vasodilators, beta-blocker, ICD if high risk. PE → anticoagulation |
| Carotid sinus | Avoid tight collars/neck manipulation. Pacemaker if cardioinhibitory type with recurrent syncope |
| Situational | Avoid triggers (cough, micturition, defecation). Sit to urinate. Treat underlying cough. Counter-pressure maneuvers |
Disposition
- Admit if: Abnormal ECG, exertional syncope, syncope while supine, significant injury, known structural heart disease, family history of sudden cardiac death, new murmur, older age with no clear cause
- Discharge if: Young patient, classic vasovagal prodrome, situational trigger, orthostatic (correctable), normal ECG, no structural heart disease, normal exam
💊 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
Most Common
Vasovagal (~50%). Prodrome: warmth, nausea, diaphoresis, tunnel vision → brief LOC → rapid recovery.
High-Risk ECG
Brugada, long QT, WPW, CHB, Mobitz II, new BBB, epsilon waves (ARVC), ST elevation.
Admit If
Exertional syncope, supine syncope, FH sudden death, structural heart disease, abnormal ECG, older patient.
Workup
ECG (everyone). Echo if cardiac suspected. Orthostatics. Labs: glucose, Hgb, troponin if cardiac concern.
Low Risk
Young, vasovagal prodrome, situational (cough/micturition), orthostatic, normal ECG → discharge with follow-up.
Young Athlete SCA
Mandatory workup: echo (HCM), ECG (WPW/QT), cardiac MRI (ARVC), genetic testing. Survivors get ICD.
CardiologyAcute/Outpatient
Syncope
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.
Classification
| Category | Mechanism | Examples | Prognosis |
|---|---|---|---|
| Reflex (neurally mediated) | Inappropriate vasodilation ± bradycardia | Vasovagal, situational (cough, micturition), carotid sinus hypersensitivity | Benign |
| Orthostatic hypotension | Volume depletion or autonomic failure | Dehydration, hemorrhage, meds (alpha-blockers, diuretics), autonomic neuropathy (DM, Parkinson) | Treat underlying cause |
| Cardiac -Arrhythmic | Brady or tachy → low CO | Complete heart block, VT, long QT, Brugada, sick sinus, pacemaker malfunction | Dangerous |
| Cardiac -Structural | Fixed obstruction → low CO | Severe AS, HOCM, massive PE, aortic dissection, cardiac tamponade, atrial myxoma | Dangerous |
Key Epidemiology
- ~40% of people will experience syncope in their lifetime. 1-3% of ED visits.
- Reflex syncope accounts for ~60% of cases (most common overall)
- Cardiac syncope: ~15% of cases but accounts for majority of syncope-related deaths
- Unexplained in ~15-20% even after full workup
- 1-year mortality: vasovagal ~0%, cardiac syncope ~18-33%
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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
- Echo results: Structural heart disease? EF? Valvular disease? HOCM?
- Medication review: Any QT-prolonging drugs? Antihypertensives? Alpha-blockers?
- Recurrence: Any further episodes? Near-syncope? Presyncope?
- EP consult: If cardiac etiology suspected -document their recs
- Disposition plan: Safe for discharge? Need event monitor? Follow-up arranged?
🧪 Workup
Initial Evaluation (ALL Patients)
- Detailed history: Position (supine/standing/exertional), prodrome, witnesses, duration, recovery, medications, family hx of sudden death
- Physical exam: Orthostatic vitals (supine → standing, wait 3 min), cardiac auscultation (murmurs), carotid bruits, neurologic exam
- 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
- Tilt table test: Recurrent syncope suspected vasovagal but diagnosis unclear. Sensitivity 26-80%.
- 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 |
🚨 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 massive PE with hemodynamic compromise.
Reflex (Vasovagal) Syncope
- First-line: Education, reassurance, trigger avoidance, increase salt & fluid intake (2-3L/day), physical counterpressure maneuvers (leg crossing, hand grip, squatting) PC-Trial, 2006
- Second-line: Midodrine (ProAmatine) 5-10mg TID (alpha-1 agonist, raises BP). Fludrocortisone 0.1-0.2mg daily (volume expansion).
- 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
Orthostatic Syncope
- Medication review: Reduce/stop offending agents (diuretics, alpha-blockers, vasodilators, TCAs)
- Non-pharmacologic: Compression stockings (30-40 mmHg), abdominal binder, rise slowly, elevate HOB, increase salt & fluids
- 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.
⚡ Summary
Summary
Definition
Transient LOC from global cerebral hypoperfusion. Rapid onset, short duration, spontaneous recovery.
Most Common
Vasovagal (~60%). Prodrome of warmth, nausea, diaphoresis. Positional trigger. Benign.
Most Dangerous
Cardiac syncope (~15%). No prodrome, exertional, abnormal ECG, structural heart disease. 18-33% 1-year mortality.
Key Test
12-lead ECG -mandatory for ALL syncope patients. History + ECG identifies cause in ~50%.
Admit If
Abnormal ECG, structural heart disease, exertional, supine syncope, hx SCD in family, significant injury, suspected PE/ACS.
Pearl
Routine CT head, EEG, carotid US have near-zero yield. Don't shotgun -use the history and ECG.
📄 One Pager
One-Pager
Syncope
Risk Stratification & Workup
Categories
Reflex/vasovagal (60%) -benign, prodrome, positional trigger. Orthostatic (15%) -meds, dehydration, autonomic. Cardiac arrhythmic (10%) -heart block, VT, long QT, Brugada, WPW. Cardiac structural (5%) -AS, HOCM, PE, tamponade.
Mandatory Workup
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.
High-Risk ECG Flags
Bifascicular block, QTc > 500, Brugada (coved ST V1-V3), WPW (short PR + delta wave), Mobitz II/CHB, VT/NSVT, pathologic Q waves (old MI).
Risk Scores
SFSR (CHESS): CHF, Hct < 30, ECG abnl, SOB, SBP < 90 -any positive = high risk. CSRS: validated 30-day risk, score -3 to +11. ROSE: BNP ≥ 300 strongest predictor.
EmergentCardiology
Heart Block & Bradyarrhythmias
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. | No |
| 2nd Degree -Mobitz I (Wenckebach) | Progressive PR prolongation → dropped QRS. Grouped beating pattern. | AV node (above His) | 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)
- Symptomatic Mobitz I not due to reversible cause
- Symptomatic sinus node dysfunction (sick sinus syndrome, tachy-brady syndrome)
- Post-MI persistent 2nd or 3rd degree block
- Alternating bundle branch block (RBBB alternating with LBBB -impending complete block)
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.
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.
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.
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
1st Degree
PR > 200ms. Benign. No treatment needed. Monitor if progressing.
2nd Degree Mobitz I
Progressive PR prolongation → dropped beat. Usually AV nodal (narrow QRS). Often benign. Observe.
2nd Degree Mobitz II
Constant PR → sudden dropped beat. Infranodal (His-Purkinje). DANGEROUS -can progress to CHB. Needs pacer.
3rd Degree (CHB)
Complete AV dissociation. Narrow escape = junctional (40-60 bpm, stable). Wide escape = ventricular (20-40, unstable).
Check First
Med list (BB, CCB, digoxin, amiodarone), K⁺ (hyperkalemia), Lyme screen, TSH, troponin (MI).
Temporary Pacing
Transcutaneous pads (bridge). Atropine for symptomatic bradycardia. Transvenous wire if unstable + awaiting permanent pacer.
📄 One Pager
Heart Block & Bradyarrhythmias -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.
HEART BLOCK & BRADYARRHYTHMIAS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
RoundsRx Licensed Content - Unauthorized Use Prohibited📄 One Pager
Cardiology · One Pager
Heart Block
Check meds and K⁺ first. Mobitz I = usually benign. Mobitz II or CHB = pacemaker. Don't delay temp pacing if symptomatic.
🧪 Types
- 1st degree: PR > 200ms. Benign. Observe.
- 2nd degree Mobitz I: progressive PR → dropped beat. AV nodal. Usually benign.
- 2nd degree Mobitz II: constant PR → sudden drop. Infranodal. DANGEROUS → pacer.
- 3rd degree (CHB): complete dissociation. Narrow escape = junctional (40-60). Wide = ventricular (20-40, unstable).
🚨 Management
- Check and hold offending meds: BB, CCB, digoxin, amiodarone
- Check K⁺ (hyperkalemia causes any degree of block)
- Symptomatic bradycardia → atropine 0.5 mg IV
- Transcutaneous pacing pads on standby
- Transvenous wire if unstable + awaiting permanent pacer
- Lyme screen and TSH if no obvious cause
💡 When Does It Need a Pacer?
- Mobitz II (risk of sudden progression to CHB)
- Third-degree AV block (symptomatic or with wide escape)
- Symptomatic sinus node dysfunction
- Post-TAVR CHB (common, may resolve -observe 24-48h)
- Alternating bundle branch block
- Exception: inferior MI CHB often resolves (observe, don't rush to pacer)
💊 Key Drugs
Atropine0.5 mg IV q3-5 min (max 3 mg)
Dopamine2-20 mcg/kg/min (bridge)
Epinephrine (Adrenalin)2-10 mcg/min (bridge)
Isoproterenol2-10 mcg/min (last resort)
⚠️ Pitfalls
- Not checking med list first (most common cause)
- Missing hyperkalemia
- Rushing to permanent pacer in inferior MI CHB
- Not placing transcutaneous pads early
RoundsRx · Cardiology · One Pager
ACC/AHA Bradycardia/Conduction 2018
EmergentCardiology
Myocarditis
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. | Stable. Mild EF reduction. | ~50% recover fully. ~25% develop chronic DCM. ~25% stable but reduced EF. |
| Fulminant | Rapid-onset cardiogenic shock within days. Severe biventricular failure. Arrhythmias. | Hemodynamic collapse. May need MCS (Impella, ECMO). | Paradoxically better long-term prognosis if they survive the acute phase -~90% recover LV function (robust immune response clears the virus). |
| Chronic active | Persistent HF symptoms > 3 months. Ongoing inflammation on biopsy. | Progressive LV dilation and dysfunction. | May progress to DCM. May need transplant evaluation. |
| Giant cell | Rapidly progressive HF + VT. Young-middle age. | Severe. Refractory arrhythmias. | Worst prognosis. Median survival ~5 months without transplant. Immunosuppression is indicated. |
Etiology
- Viral (most common) -Coxsackievirus B, parvovirus B19, HHV-6, adenovirus, SARS-CoV-2, influenza
- Autoimmune -SLE, sarcoidosis, eosinophilic myocarditis (hypersensitivity)
- Drug/toxin -immune checkpoint inhibitors (PD-1/PD-L1 -pembrolizumab, nivolumab), doxorubicin, cocaine, amphetamines
- 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 Parameters -Hypertrophic Cardiomyopathy
| 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
- Troponin -elevated, trend q6-8h
- ECG -diffuse ST changes, arrhythmias
- Echo -EF, wall motion, pericardial effusion
- Cardiac MRI (gold standard) -T2 edema, mid-myocardial LGE
- ESR, CRP
- 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), (4)
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).
Management:
- ICU, vasopressors/inotropes (dobutamine 5 mcg/kg/min + norepinephrine for MAP ≥ 65)
- 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."
Don't Miss
Giant cell myocarditis: rapid HF + VT + young. Needs biopsy. Treatment: immunosuppression. Consider transplant early.
📄 One Pager
Cardiology · One Pager
Myocarditis
Young + chest pain + troponin + new HF after viral illness. Cardiac MRI = gold standard. No NSAIDs. No exercise × 3-6 months.
🧪 Diagnosis
- Suspect: young patient + chest pain + troponin ↑ + new HF + recent viral illness
- ECG: diffuse ST changes, low voltage, arrhythmias
- Echo: reduced EF, regional or global wall motion abnormality
- Gold standard: Cardiac MRI -mid-myocardial LGE (not subendocardial like MI)
🚨 Management
- Standard HF therapy: ACEi + low-dose BB + diuretics PRN
- Avoid NSAIDs (worsen myocardial necrosis in animal models)
- Activity restriction: no exercise × 3-6 months minimum
- Arrhythmia monitoring: telemetry (VT/VF risk during active inflammation)
- Follow-up echo at 3-6 months (EF should recover in most viral cases)
⚠️ Return to Activity Criteria
- ≥ 3 months from symptom onset
- EF normalized on echo
- No LGE on cardiac MRI (or stable/reduced)
- No arrhythmias on Holter + exercise stress test
- Normal inflammatory markers (CRP, troponin)
- Gradual return, individualized [ESC Sports Cardiology 2020]
💊 Key Drugs
ACEi/ARBStandard HF dosing
Low-dose BBCarvedilol or metoprolol
DiureticsFurosemide PRN for congestion
AvoidNSAIDs, intense exercise
⚠️ Pitfalls
- NSAIDs in acute myocarditis
- Early return to exercise (arrhythmia risk)
- Missing giant cell myocarditis (rapid HF + VT → biopsy)
- Confusing with STEMI (check MRI pattern)
RoundsRx · Cardiology · One Pager
ESC Myocarditis 2021 · ESC Sports Cardiology 2020
ChronicCardiology
Hypertrophic Cardiomyopathy
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.
What WORSENS obstruction
- ↓ Preload -dehydration, Valsalva, standing, diuretics (smaller LV cavity → septum and MV closer together)
- ↓ Afterload -vasodilators, exercise-induced vasodilation
- ↑ Contractility -exercise, inotropes, digoxin, catecholamines
What IMPROVES obstruction
- ↑ Preload -IV fluids, leg elevation, squatting
- ↑ Afterload -phenylephrine (alpha agonist)
- ↓ Contractility / HR -beta-blockers, verapamil
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.
- Symptoms: exertional dyspnea, syncope (especially exertional -red flag), chest pain, palpitations
- ECG: LVH, deep septal Q waves (V1–V3, "dagger" Q waves), T-wave inversions
- Echo (diagnostic): septal wall thickness ≥ 15 mm, SAM of mitral valve, LVOT gradient, MR
🚨 Management
Medical Therapy
| Drug | Role | Notes |
|---|---|---|
| Beta-blocker (non-vasodilating) 1ST LINE | ↓ HR, ↓ contractility, ↑ diastolic filling time | Metoprolol or propranolol preferred. Titrate to resting HR 60–65. Do NOT use carvedilol (vasodilating properties worsen obstruction). |
| Verapamil (Calan) 2ND LINE | ↓ HR, ↓ contractility, improves diastolic relaxation | If BB intolerant. Avoid in severe resting obstruction (gradient > 100 mmHg) -vasodilatory effect may worsen hemodynamics. |
| Disopyramide ADD-ON | Negative inotrope (Class Ia antiarrhythmic) | Added to BB for refractory symptoms. Must combine with BB (disopyramide alone → reflex tachycardia from anticholinergic effects). |
| Mavacamten (Camzyos) BREAKTHROUGH | Cardiac myosin inhibitor. Directly reduces contractility by decreasing myosin-actin cross-bridge formation. | 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.
- ICD indicated (secondary prevention): prior cardiac arrest, sustained VT
- ICD considered (primary prevention) if ≥ 1 major risk factor:
| Risk Factor | Details |
|---|---|
| Family history of SCD | 1st degree relative with SCD from HCM (especially < 50 yo) |
| Massive LVH | Max wall thickness ≥ 30 mm |
| Unexplained syncope | Recent (< 6 months), especially exertional |
| NSVT | Non-sustained VT on Holter (≥ 3 beats at ≥ 120 bpm) |
| Abnormal BP response to exercise | Failure of SBP to rise ≥ 20 mmHg with exercise (especially age < 40) |
| Extensive LGE on MRI | ≥ 15% LGE → significant fibrosis → arrhythmia substrate |
| LV apical aneurysm | Independent risk for VT |
🧪 Workup
Workup
- Echo -wall thickness, LVOT gradient, SAM
- 48h Holter -NSVT for SCD
- Exercise stress -hypotension
- Cardiac MRI -fibrosis, apical HCM
- Genetic testing
- Family echo -first-degree relatives
📋 On Rounds
Why does the HCM murmur get louder with Valsalva?
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.
What is mavacamten and how does it change HCM management?
Mavacamten (Camzyos) is a first-in-class cardiac myosin inhibitor -it reduces the number of actin-myosin cross-bridges during systole, directly decreasing contractility and LVOT gradient. [EXPLORER-HCM, 2020: reduced LVOT gradient from ~50 to ~10 mmHg, improved exercise capacity and symptoms. Approved for symptomatic obstructive HCM (NYHA II-III). Key risk: excessive reduction in EF -requires echo monitoring (EF q12 weeks).
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 beta-blocker inadequate: add disopyramide 100 mg QID (negative inotrope — reduces LVOT gradient)
- Mavacamten 5 mg daily if refractory to above EXPLORER-HCM, 2020
- AVOID: vasodilators (ACEi, nitrates), diuretics (reduce preload → worsen obstruction), digoxin (positive inotrope)
- 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
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
⚡ Summary
Summary
Diagnosis
Wall thickness ≥ 15mm (any segment) not explained by loading conditions. Genetic (autosomal dominant).
Obstruction
LVOT gradient ≥ 30 mmHg at rest or with provocation. SAM of mitral valve. Worsened by dehydration, Valsalva, vasodilators.
Medications
BB first-line. Verapamil second-line. Disopyramide for refractory. Mavacamten (myosin inhibitor) EXPLORER-HCM, 2020.
Avoid
Vasodilators (ACEi, nitrates), diuretics, digoxin, dehydration -all worsen obstruction.
SCD Risk
FH sudden death, unexplained syncope, NSVT, wall thickness ≥ 30mm, exercise hypotension. Consider ICD.
Activity
No competitive sports. Low-moderate exercise may be acceptable based on individual risk assessment.
📄 One Pager
Hypertrophic Cardiomyopathy -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.
HYPERTROPHIC CARDIOMYOPATHY -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
Cardiology · One Pager
Hypertrophic Cardiomyopathy
Wall ≥ 15mm. Obstruction worsened by dehydration + vasodilators. BB first-line. Mavacamten = new. SCD risk stratification in all patients.
🧪 Diagnosis
- LV wall thickness ≥ 15mm (any segment) not explained by loading conditions
- Autosomal dominant (screen first-degree relatives)
- LVOT obstruction: gradient ≥ 30 mmHg at rest or provocation
- SAM of mitral valve on echo
🚨 Management
- Beta-blocker first-line (reduce HR → improve filling time → reduce obstruction)
- Verapamil second-line (if BB-intolerant)
- Disopyramide for refractory obstruction
- Mavacamten (cardiac myosin inhibitor) EXPLORER-HCM, 2020
- Septal myectomy or alcohol septal ablation if refractory to meds
💀 SCD Risk Assessment
- FH sudden cardiac death < 50 years
- Unexplained syncope
- Non-sustained VT on Holter
- Max wall thickness ≥ 30mm
- Exercise hypotension
- ICD implantation based on risk score (≥ 1 major risk factor → discuss ICD)
💊 Key Drugs
Metoprolol50-200 mg BID
Verapamil120-480 mg/day
Disopyramide100-200 mg TID
Mavacamten5-15 mg daily
⚠️ Pitfalls
- Vasodilators (ACEi, nitrates) → worsen obstruction
- Diuretics → reduce preload → worsen obstruction
- Digoxin → increases contractility → worsen obstruction
- Dehydration → worse obstruction
- No competitive sports
RoundsRx · Cardiology · One Pager
ACC/AHA HCM 2020 · EXPLORER-HCM 2020
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 | K⁺ 4.0–5.0 (RAAS inhibitors + MRA raise K⁺, diuretics lower it). Cr rise ≤ 30% acceptable on ACEi/ARB/ARNI. Na < 130 → fluid restrict. |
| Blood pressure | Each clinic visit; home monitoring encouraged | 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. |
| 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. |
| Functional status (NYHA class) | Each visit | Dyspnea, exercise tolerance, orthopnea, PND. NYHA III–IV despite optimal GDMT → advanced HF referral (LVAD/transplant evaluation). |
| Iron studies | At diagnosis, then annually | 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.
CardiologyChronicCommon
Heart Failure -Chronic Management
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. | Maximize GDMT. Consider ICD/CRT. Diuretic optimization. |
| IV | 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)
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 |
Sacubitril/valsartan (Entresto) Start 24/26 mg BID → target 97/103 mg BID |
97/103 mg BID | PARADIGM-HF, 2014 | 20% reduction in CV death vs enalapril | Hold ACEi 36h before starting (angioedema risk). Hypotension. Do not use with ACEi. Avoid if SBP < 100. |
| 1. ACEi/ARB (if ARNI not tolerated) |
Enalapril (Vasotec) 10–20 mg BID Lisinopril (Zestril) 20–40 mg daily Losartan (Cozaar) 50–150 mg daily Valsartan (Diovan) 160 mg BID |
Max tolerated | CONSENSUS, 1987 SOLVD, 1991 |
~25–30% | Hyperkalemia, AKI, cough (ACEi). Monitor Cr + K⁺ at 1–2 weeks. Cr rise ≤ 30% acceptable. |
| 2. Beta-blocker 1ST LINE |
Carvedilol (Coreg) 3.125 → 25 mg BID Metoprolol succinate (Toprol-XL) 12.5 → 200 mg daily Bisoprolol 1.25 → 10 mg daily |
Max tolerated of one of the three | MERIT-HF, 1999 COPERNICUS, 2001 CIBIS-II, 1999 |
~35% | 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 |
Spironolactone (Aldactone) 12.5–50 mg daily or Eplerenone (Inspra) 25–50 mg daily |
25–50 mg daily | RALES, 1999 EMPHASIS-HF, 2011 |
~30% | Hyperkalemia -monitor K⁺ at 3 days, 1 week, monthly. Avoid if K⁺ > 5.0 or eGFR < 30. Eplerenone = less gynecomastia than spironolactone. |
| 4. SGLT2 inhibitor 1ST LINE |
Dapagliflozin (Farxiga) 10 mg daily or Empagliflozin (Jardiance) 10 mg daily |
10 mg daily (no titration needed) | DAPA-HF, 2019 EMPEROR-Reduced, 2020 |
🫀 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.
| Domain | HFrEF (EF ≤ 40%) | HFpEF (EF ≥ 50%) |
|---|---|---|
| Core pathology | Systolic dysfunction -weakened pump. Dilated LV, ↓ contractility. | 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 BENEFIT PARAGON-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 BENEFIT RALES, 1999: spironolactone reduced mortality 30% in severe HFrEF. EPHESUS, 2003: eplerenone in post-MI HFrEF. | POSSIBLE BENEFIT TOPCAT, 2014: overall negative, but Americas subgroup showed benefit. Consider if symptomatic despite diuretics. |
| SGLT2 inhibitor | MORTALITY BENEFIT DAPA-HF, 2019: dapagliflozin reduced worsening HF/CV death 26%. EMPEROR-Reduced, 2020: empagliflozin confirmed class effect. | HF HOSPITALIZATION BENEFIT EMPEROR-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. | EMERGING STEP-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, 2002 SCD-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
- Start all 4 pillars of GDMT simultaneously: sacubitril/valsartan 24/26 mg BID, carvedilol 3.125 mg BID, spironolactone 25 mg daily, empagliflozin 10 mg daily DAPA-HF, 2019
- 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 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 | K⁺ 4.0–5.0 (RAAS inhibitors + MRA raise K⁺, diuretics lower it). Cr rise ≤ 30% acceptable on ACEi/ARB/ARNI. Na < 130 → fluid restrict. |
| Blood pressure | Each clinic visit; home monitoring encouraged | 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. |
| 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. |
| Functional status (NYHA class) | Each visit | Dyspnea, exercise tolerance, orthopnea, PND. NYHA III–IV despite optimal GDMT → advanced HF referral (LVAD/transplant evaluation). |
| Iron studies | At diagnosis, then annually | 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.
🧪 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.
- 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) | Carvedilol 3.125 mg BID → 25 mg BID Metoprolol XL 12.5 mg → 200 mg daily | HR ≥ 60, SBP ≥ 90. Do NOT start during decompensation. Only these 3 BBs have evidence. |
| 3. MRA | Spironolactone (Aldactone) or eplerenone (Inspra) | Spironolactone 12.5 → 25–50 mg daily Eplerenone 25 → 50 mg daily | K⁺ < 5.0 and Cr < 2.5 before starting. Recheck at 1 week. Eplerenone if gynecomastia from spironolactone. |
| 4. SGLT2i | Dapagliflozin (Farxiga) or empagliflozin (Jardiance) | Dapagliflozin 10 mg daily Empagliflozin 10 mg daily | 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%.
- 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
⚡ 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.
⚡ Summary
Summary
4 Pillars GDMT
ARNI (or ACEi) + evidence-based BB + MRA + SGLT2i. Start all four early. Each independently reduces mortality.
Key Trials
ARNI [PARADIGM-HF]. SGLT2i [DAPA-HF, EMPEROR-Reduced]. MRA [RALES]. BB [COPERNICUS, MERIT-HF].
Diuresis Goal
Net −1 to 2 L/day. Daily weights. UOP 100-150 mL/hr after IV furosemide. Metolazone for resistance.
ICD Criteria
EF ≤ 35% on max GDMT × 3 months, NYHA II-III, life expectancy > 1 year. CRT if LBBB + QRS ≥ 150.
HFpEF
EF ≥ 50%. Diuresis for congestion. SGLT2i (empagliflozin) [EMPEROR-Preserved]. Treat comorbidities: HTN, AF, obesity.
Discharge
Optimize GDMT before discharge. Weight target. Fluid restrict 1.5-2L/day. Follow-up within 7 days. Cardiac rehab.
📄 One Pager
One Pager -Heart Failure -Chronic Management
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
HEART FAILURE -CHRONIC MANAGEMENT -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
Cardiology · One Pager
CHF -Acute & Chronic
4 pillars of GDMT: ARNI + BB + MRA + SGLT2i. Start all four early. Diuresis for congestion. ICD if EF ≤ 35% on max GDMT × 3 months.
🧪 Classification
Warm/Wet (most common ADHF): diuretics. Cold/Wet: inotropes + diuretics. Cold/Dry: careful fluids. Warm/Dry: optimize GDMT outpatient.
🚨 Acute Management
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
- Discharging without GDMT optimization + 7-day f/u
RoundsRx · Cardiology
ACC/AHA HF 2022 · PARADIGM-HF · DAPA-HF
NephrologyCommon
Acute Kidney Injury (AKI)
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
KDIGO Staging
| Stage | Creatinine Criteria | Urine Output |
|---|---|---|
| 1 | ↑ ≥ 0.3 in 48h OR 1.5–1.9× baseline | < 0.5 mL/kg/hr × 6–12h |
| 2 | 2.0–2.9× baseline | < 0.5 mL/kg/hr × ≥ 12h |
| 3 | ≥ 3× baseline OR ≥ 4.0 mg/dL OR RRT initiated | < 0.3 mL/kg/hr × ≥ 24h or anuria × 12h |
Causes -The Classic 3-Category Framework
Pre-Renal (most common -60–70%)
- Volume depletion: vomiting, diarrhea, poor intake, diuresis
- Low CO states: heart failure, cardiogenic shock
- Renal hypoperfusion: ACEi/ARB in bilateral RAS, NSAIDs, hepatorenal syndrome
Intrinsic Renal (20–30%)
- ATN (most common intrinsic): ischemia, nephrotoxins (aminoglycosides, contrast, myoglobin, vancomycin)
- Glomerulonephritis: RBCs + protein + RBC casts on UA
- AIN (interstitial nephritis): drug-induced (PCN, NSAIDs, PPIs), eosinophiluria
- Vascular: renal artery thrombosis, TTP, HUS
Post-Renal (5–10%)
- Bilateral ureteral obstruction, BPH, bladder outlet obstruction
- Check with renal ultrasound + bladder scan
🧪 Workup & Diagnosis
Workup Algorithm
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.
- BMP -creatinine trend, K⁺, bicarb, BUN:Cr ratio (> 20:1 suggests pre-renal)
- CBC, LFTs
- Complement, ANA, ANCA, anti-GBM -if GN suspected
- Renal ultrasound -hydronephrosis, echogenicity, kidney size
- Review all medications -nephrotoxins, ACEi/ARBs, NSAIDs
🚨 Management
Management by Category
Pre-Renal AKI
- Volume resuscitation with IV crystalloid (LR preferred SMART, 2018)
- Hold ACEi/ARBs, NSAIDs, diuretics until creatinine stabilizes
- Treat underlying cause (heart failure, hepatorenal syndrome, hemorrhage)
- Expect creatinine to improve within 24–48h if truly pre-renal
ATN (Intrinsic)
- Supportive care -no specific treatment accelerates recovery
- Strict I&Os, careful fluid management (avoid overload)
- Aggressive electrolyte management (K⁺, bicarb, phosphate)
- Avoid contrast, nephrotoxins
Post-Renal AKI
- Foley catheter if BPH/bladder outlet obstruction → expect post-obstructive diuresis
- Urology consult for ureteral obstruction (stenting vs percutaneous nephrostomy)
- Monitor for post-obstructive diuresis (replace 50–75% UOP with IV fluids)
Indications for Emergent Dialysis -AEIOU
Mnemonic: AEIOU -If any of these are refractory to medical management, call nephrology for emergent dialysis.
| Letter | Indication | Details |
|---|---|---|
| A | Acidosis | Severe metabolic acidosis (pH < 7.1) refractory to bicarb infusion |
| E | Electrolytes | Refractory hyperkalemia (K⁺ > 6.5 with ECG changes despite medical Rx -insulin/glucose, calcium, patiromer/Lokelma) |
| I | Ingestions | Toxic alcohols (methanol, ethylene glycol), lithium, salicylates -dialyzable toxins |
| O | Overload | Volume overload causing pulmonary edema/respiratory failure refractory to diuretics |
| U | Uremia | Uremic encephalopathy (asterixis, AMS, seizures), uremic pericarditis (friction rub -pericardial effusion risk) |
Timing of Dialysis -Don't Rush. Early initiation of RRT does NOT improve mortality vs a delayed/watchful strategy STARRT-AKI, 2020 AKIKI, 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)
Step 1 -Pre-renal vs Intrinsic vs Post-renal:
- BUN/Cr ratio: 42 (> 20:1 → suggests pre-renal)
- FENa: 0.4% (< 1% → pre-renal)
- Urine Na: 8 mEq/L (< 20 → avid Na retention = pre-renal)
- UA: No casts, no protein (argues against ATN or glomerulonephritis)
- Renal US: No hydronephrosis (rules out post-renal obstruction)
Assessment: Pre-renal AKI from volume depletion. Management: IV LR boluses, hold ACEi. Cr improved to 1.8 at 24h → confirms pre-renal.
📋 Case 2 — Contrast-Induced AKI
Patient: 68M with CKD Stage 3 (baseline Cr 1.8), underwent cardiac catheterization with contrast 48h ago. Cr now 3.2. UOP declining.
Workup:
- FENa: 2.8% → intrinsic (ATN pattern)
- UA: Muddy brown granular casts → classic for ATN
- Timeline: Cr rise 24–72h post-contrast = classic contrast nephropathy
Management:
- 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.
- Hyperkalemia: Calcium gluconate 1g IV (cardioprotection), insulin + D50, kayexalate. Continuous telemetry.
- 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
First Move
Bladder scan + renal U/S to rule out obstruction. Then UA with micro + FENa to localize.
Pre-Renal
FENa < 1%, BUN:Cr > 20. Treat with fluids, hold nephrotoxins. Creatinine improves in 24–48h.
ATN
FENa > 2%, muddy brown casts. Supportive care. No diuretics force recovery. Avoid all nephrotoxins.
Post-Renal
Hydronephrosis on U/S. Foley or urology consult. Watch for post-obstructive diuresis.
Dialysis Triggers
AEIOU: Acidosis, Electrolytes, Ingestion, Overload, Uremia
Biggest Pitfall
Missing contrast nephropathy, or giving fluids to an ATN patient expecting pre-renal response -causes volume overload.
📄 One Pager
Nephrology · One Pager
Acute Kidney Injury
Pre-renal, intrinsic, or post-renal. Bladder scan + renal U/S first. FENa localises 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)
Rounds · Nephrology
KDIGO AKI Guidelines 2012
📋 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
- Monitor UOP ≥ 0.5 mL/kg/hr
- Cr improved 3.1 → 2.2 → 1.4 over 72h confirming pre-renal recovery
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.
Key findings: Cr 8.2 (baseline 1.1), pH 7.18, bicarb 12. Renal US: bilateral hydronephrosis. Bladder scan 1,200 mL.
Management:
- Calcium gluconate 1g IV stat for cardiac membrane stabilization
- Foley catheter — 1,400 mL immediate drainage; anticipate post-obstructive diuresis
- Insulin 10U + D50 + albuterol 10 mg neb for K⁺ shifting
- 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.
Monitoring Parameters -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.
💊 Medications
Key Medications -Myocarditis
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
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).
GFR Staging (KDIGO)
| Stage | GFR (mL/min/1.73m²) | Description | Mortality Risk |
|---|---|---|---|
| G1 | ≥ 90 | Normal or high (with kidney damage markers) | Baseline |
| G2 | 60–89 | Mildly decreased | Slightly increased |
| G3a | 45–59 | Mild-moderately decreased | Moderately increased |
| G3b | 30–44 | Moderate-severely decreased | High |
| G4 | 15–29 | Severely decreased | Very high |
| G5 | < 15 | Kidney failure (ESKD) | Highest |
Albuminuria Categories
| Category | UACR (mg/g) | Description |
|---|---|---|
| A1 | < 30 | Normal to mildly increased |
| A2 | 30–300 | Moderately increased (microalbuminuria) |
| A3 | > 300 | Severely increased (macroalbuminuria) -high ESKD risk |
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. |
| Other | ~14% | Reflux nephropathy, obstructive uropathy, interstitial nephritis, amyloidosis, myeloma kidney, sickle cell. |
Pathophysiology
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).
- Moderate (G3b–G4): Fatigue, nocturia (loss of concentrating ability), mild edema, anemia symptoms, pruritus.
- Severe (G5 / ESKD): Uremic symptoms -nausea, anorexia, metallic taste, asterixis, encephalopathy, pericarditis, bleeding diathesis (platelet dysfunction), volume overload, Kussmaul breathing (acidosis).
Uremic emergency: Uremic pericarditis (friction rub), uremic encephalopathy (asterixis, seizures), or refractory volume overload → emergent dialysis indication (AEIOU mnemonic from AKI topic).
🧪 Workup & Diagnosis
Diagnostic Workup
| Test | Purpose |
|---|---|
| BMP (Cr, BUN) | Calculate eGFR (CKD-EPI 2021). Two values ≥ 3 months apart confirm chronicity. |
| Urinalysis with micro | Proteinuria, hematuria, casts. Active sediment (RBC casts) → GN. Bland sediment → DM/HTN nephrosclerosis. |
| UACR (spot urine) | Quantify albuminuria. Most important prognostic marker. Repeat × 2 to confirm (transient proteinuria is common). |
| Renal ultrasound | Kidney size (small bilateral = chronic), echogenicity (increased = fibrosis), cysts (ADPKD), hydronephrosis (obstruction). |
| CBC | Anemia of CKD (normocytic, normochromic). EPO deficiency begins at G3. |
| Ca²⁺, PO₄, PTH, Vitamin D (25-OH) | CKD-MBD evaluation. Start monitoring at G3a. Expect: ↓ Ca, ↑ PO₄, ↑ PTH, ↓ Vit D. |
| Iron studies (ferritin, TSAT) | Iron deficiency is common and must be corrected before EPO agents. Target: ferritin > 100, TSAT > 20%. |
| Lipid panel | CVD risk assessment. CKD is a coronary risk equivalent. |
| HbA1c | Glycemic control if diabetic. Note: HbA1c is unreliable in ESKD (shortened RBC lifespan, EPO use). |
| Hepatitis B/C, HIV | Screen all CKD patients. Hep B vaccination if non-immune (double dose in CKD). |
When to Pursue Etiology
- Active urine sediment (RBC casts, dysmorphic RBCs) → glomerulonephritis workup: complement levels (C3/C4), ANA, anti-dsDNA, ANCA, anti-GBM, SPEP/UPEP, hepatitis serologies
- Nephrotic-range proteinuria (> 3.5 g/day) without DM → consider renal biopsy
- Rapidly declining GFR (> 5 mL/min/year) → urgent nephrology referral + biopsy
- 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
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.
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 34%. 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.
DAPA-CKD, 2020: dapagliflozin reduced CKD progression by 34%. 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.
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.
| Parameter | CKD G3–G4 | CKD G5 / Dialysis | Treatment |
|---|---|---|---|
| Phosphate | Keep in normal range | Target 3.5–5.5 mg/dL | Dietary restriction → phosphate binders: sevelamer (Renvela), calcium acetate (PhosLo), lanthanum (Fosrenol) |
| Calcium | Maintain normal | Avoid hypercalcemia | Avoid calcium-based binders if hypercalcemic. Calcitriol (Rocaltrol) or paricalcitol (Zemplar) for active vitamin D. |
| PTH | Trend -no target | 2–9× upper normal | Calcitriol, cinacalcet (Sensipar), or parathyroidectomy if refractory. |
| Vitamin D (25-OH) | Replete if < 30 ng/mL | Replete | Ergocalciferol or cholecalciferol (inactive form) for deficiency. Active forms for secondary hyperPTH. |
Anemia of CKD
EPO production drops as renal mass decreases (begins G3). Results in normocytic, normochromic anemia. Always rule out iron deficiency first.
| Step | Action | Target |
|---|---|---|
| 1. Iron first | IV iron (ferric carboxymaltose or iron sucrose) if ferritin < 100 or TSAT < 20% | Ferritin 200–500, TSAT 20–30% |
| 2. ESA if needed | Epoetin alfa (Epogen/Procrit) or darbepoetin (Aranesp). Start if Hgb < 10 after iron repletion. | Hgb 10–11.5 g/dL. Do NOT target > 13 TREAT, 2009: ↑ stroke risk. CHOIR, 2006: ↑ CV events. |
| 3. HIF-PHI (newer) | Roxadustat (Evrenzo) -oral HIF-prolyl hydroxylase inhibitor. Stimulates endogenous EPO. | Alternative to injectable ESAs. Approved in CKD + dialysis. |
Never target Hgb > 13 g/dL with ESAs. TREAT, 2009: doubled stroke risk. CHOIR, 2006: increased CV events. CREATE, 2006: no benefit. Target 10–11.5 only.
Metabolic Acidosis
Impaired ammonium excretion → non-anion-gap metabolic acidosis (early) or anion-gap (late, from retained uremic toxins). Acidosis accelerates CKD progression, worsens bone disease, and promotes muscle wasting.
- Target serum bicarb ≥ 22 mEq/L
- Sodium bicarbonate tablets 650–1300 mg PO TID (1–3 mEq/kg/day)
- Bicarb CKD Progression Trial, 2010: bicarb supplementation slowed CKD progression by 60%
Other Complications
- Hyperkalemia -from impaired K⁺ excretion + ACEi/ARB/MRA. Manage with dietary restriction, patiromer (Veltassa), sodium zirconium cyclosilicate (Lokelma). Do NOT stop ACEi/ARB unless K⁺ > 5.5 persistently.
- Volume overload / edema -loop diuretics (furosemide). Dose escalation needed as GFR declines. Thiazides lose efficacy below GFR 30 (exception: metolazone for synergy).
- Cardiovascular disease -#1 cause of death in CKD. CKD is a coronary risk equivalent. Statin for all SHARP, 2011. Manage HTN aggressively.
- Uremic pruritus -gabapentin (renal dose), emollients, UVB phototherapy, difelikefalin (Korsuva) for dialysis patients.
- 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. |
🏥 Dialysis & Transplant
When to Start Dialysis
Mnemonic: AEIOU -Same as AKI. Initiate when medical management fails, not based on a GFR number alone.
| Indication | Details |
|---|---|
| A -Acidosis | Refractory metabolic acidosis despite oral bicarb |
| E -Electrolytes | Refractory hyperkalemia despite binders + dietary restriction |
| I -Intoxication | Uremic encephalopathy, uremic pericarditis (absolute indication) |
| O -Overload | Refractory volume overload despite max diuretics |
| U -Uremia | 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) | 3×/week, 3–4 hrs/session | Most ESKD patients. Rapid solute/fluid removal. | Hemodynamic instability, vascular access complications, in-center schedule burden. |
| Peritoneal dialysis (PD) | Tenckhoff catheter (peritoneal) | Daily exchanges (CAPD) or nightly cycler (APD) | Patient autonomy, home-based, preserves residual renal function longer, better for hemodynamically fragile patients. | Peritonitis risk, protein loss, not ideal if prior abdominal surgery/hernias. |
| CRRT | Temporary dialysis catheter | Continuous (ICU only) | Hemodynamically unstable ICU patients (septic shock). Gentler fluid/solute removal. | 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.
📋 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).
Case 2: CKD Stage 4 — Pre-Dialysis Planning
Presentation: 75F with CKD G4. eGFR 18. Labs: bicarb 18, K⁺ 5.6, Hgb 9.2, PTH 310, PO₄ 5.4.
Active Problem List and Plan:
- Metabolic acidosis (bicarb 18): Start Sodium Bicarbonate 650 mg TID — target bicarb ≥ 22 (slows CKD progression per de Brito-Ashurst, 2009)
- 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."
Monitoring Parameters -Chronic Kidney Disease
| Parameter | Frequency | Target / Action |
|---|---|---|
| eGFR and UACR | q3–6 months | Track progression rate. eGFR decline > 5 mL/min/year = rapid progression → reassess treatment, nephrology referral. UACR reduction with ACEi/ARB/SGLT2i = treatment working. |
| BMP (K+, bicarb, Ca, PO4) | q3–6 months (more often in G4–G5) | K+ < 5.5 (on RAAS blockade). Bicarb ≥ 22 (supplement if low). Ca/PO4 for CKD-MBD monitoring. |
| PTH | Annually (G3–G4), q3–6mo (G5/dialysis) | Rising PTH = secondary hyperparathyroidism → add phosphate binders, calcitriol, cinacalcet. Target 2–9x ULN on dialysis. |
| CBC (anemia) | q3–6 months | 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.
⚡ Summary
Summary
Staging
G1 (≥90), G2 (60-89), G3a (45-59), G3b (30-44), G4 (15-29), G5 (<15). Albuminuria: A1 < 30, A2 30-300, A3 > 300.
Slow Progression
ACEi/ARB (proteinuria reduction) + SGLT2i [CREDENCE, DAPA-CKD] + BP < 130/80 + A1c < 7 + avoid nephrotoxins.
Complications
Anemia (EPO), mineral bone disease (PTH/Ca/PO₄/VitD), metabolic acidosis (bicarb), hyperkalemia, volume overload.
Refer Nephrology
eGFR < 30, rapidly declining GFR, persistent proteinuria (UACR > 300), refractory HTN/hyperK/acidosis.
Prepare for ESKD
Fistula referral at eGFR ~20 (needs 3-6 months to mature). Transplant eval at eGFR ~20. Dialysis at eGFR ~5-10 or symptoms.
Avoid
NSAIDs, contrast (if eGFR < 30 -hydrate if needed), aminoglycosides, gadolinium (if eGFR < 30 -NSF risk).
📄 One Pager
Nephrology · One Pager
Chronic Kidney Disease
Slow progression: ACEi/ARB + SGLT2i + BP < 130/80. Manage complications: anemia, MBD, acidosis, hyperK. Refer nephrology at eGFR < 30. Fistula at eGFR ~20.
🧪 Staging
G1-5 by eGFR. A1-3 by albuminuria (UACR). Both determine prognosis and treatment intensity. eGFR < 60 for > 3 months = CKD.
🚨 Slow Progression
ACEi/ARB (reduce proteinuria). SGLT2i [CREDENCE, DAPA-CKD]. BP target < 130/80 [SPRINT]. A1c < 7. Avoid nephrotoxins (NSAIDs, contrast, aminoglycosides).
💊 Manage Complications
Anemia: iron first, then ESA (target Hgb 10-11). MBD: phosphate binders, calcitriol, check PTH. Acidosis: bicarb supplementation if < 22. Hyperkalemia: dietary, patiromer/SZC.
💊 Key Drugs
Lisinopril5-40 mg daily
Dapagliflozin10 mg daily
Sevelamer800 mg TID with meals
Epoetin alfa50-300 U/kg 3×/wk
⚠️ Pitfalls
- Not starting SGLT2i (renal protection independent of diabetes)
- NSAIDs in CKD (accelerates decline + hyperK)
- Late nephrology referral (need time for fistula maturation)
- Not checking UACR annually
RoundsRx · Nephrology
KDIGO CKD 2024 · CREDENCE · DAPA-CKD · SPRINT
Clinical Tools
Clinical Calculators
Bedside calculations for rapid decision-making. Results are for clinical guidance -always apply clinical judgment.
Nephrology & Electrolytes
Anion Gap
Identifies elevated AG metabolic acidosis. Corrected for albumin.
FENa / FEUrea
Fractional excretion to differentiate pre-renal from ATN.
Corrected Sodium
Adjusts serum sodium for hyperglycemia-induced osmotic shift.
CrCl (Cockcroft-Gault)
Creatinine clearance for drug dosing. Uses ideal or actual body weight.
Corrected Calcium
Adjusts calcium for low albumin. Use ionized Ca when available.
Winter's Formula
Expected PCO₂ in metabolic acidosis. Detects concurrent respiratory disorder.
Cardiology
CHA₂DS₂-VASc
Stroke risk in atrial fibrillation. Guides anticoagulation decisions.
Wells Score (PE)
Pretest probability of pulmonary embolism.
MAP (Mean Arterial Pressure)
Estimates average arterial pressure during one cardiac cycle
QTc (Corrected QT Interval)
Bazett formula -corrects QT interval for heart rate
ASCVD Risk (Pooled Cohort)
Simplified 10-year atherosclerotic cardiovascular disease risk estimate
Pulmonology
CURB-65 (Pneumonia)
Severity scoring for community-acquired pneumonia. Guides disposition.
A-a Gradient
Alveolar–arterial oxygen gradient -evaluates oxygenation defect
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.
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. |
| 9 – 12 | Moderate | CT head. Frequent neuro checks (q1h). ICU admission. Neurosurgery consult if structural lesion. |
| 3 – 8 | Severe | 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.
- Confounders: sedation, paralysis, alcohol, metabolic encephalopathy, aphasia, orbital swelling (can't assess eye opening). Always document confounders.
- 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).
- Pupil reactivity: GCS-P = GCS − pupil reactivity score (both reactive = 0, one reactive = −1, neither reactive = −2). GCS-P adds prognostic value to GCS alone GCS-Pupils Study, 2018.
How to Present GCS on Rounds
| Scenario | What to Say |
|---|---|
| Normal / alert patient | "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).
Memory trick: ARDS = "Stiff, flooded lungs" → SPP: Sepsis, Pneumonia, Protective ventilation
Berlin Diagnostic Criteria
| Criterion | Requirement |
|---|---|
| Timing | Within 1 week of clinical insult |
| Imaging | 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.
Imaging Findings
Chest X-Ray
- Diffuse bilateral infiltrates
- "White lungs" in severe cases
CT Scan
- Dependent consolidation (gravity-dependent atelectasis)
- Ground glass opacities
- Better characterizes distribution -not required for diagnosis
Ventilator-Induced Lung Injury (VILI)
The ventilator itself can worsen ARDS. Preventing VILI is the rationale for lung-protective ventilation.
| Mechanism | Meaning |
|---|---|
| Volutrauma | Excessive tidal volume → alveolar overdistension |
| Barotrauma | High airway pressure → pneumothorax, pneumomediastinum |
| Atelectrauma | Repeated alveolar collapse and reopening → shear injury |
| Biotrauma | Mechanical injury → systemic cytokine release → MODS |
Presentation & Red Flags
- Acute onset dyspnea, tachypnea, worsening hypoxemia
- Bilateral crackles, diffuse infiltrates on CXR
- Refractory hypoxemia -O₂ sats not improving with supplemental O₂
- Decreased lung compliance (stiff lungs on vent -high plateau pressures)
- P/F < 150 despite FiO₂ 1.0 → severe ARDS, consider prone positioning immediately
- pH < 7.15 despite optimal vent → consider ECMO consultation
Oxygenation Targets
ARDS strategy allows permissive hypoxemia -deliberately accepting lower oxygen levels to avoid toxic ventilator settings.
| Parameter | Target |
|---|---|
| SpO₂ | 88–95% |
| PaO₂ | 55–80 mmHg |
Permissive Hypercapnia
Low tidal volume may cause CO₂ retention. This is acceptable as long as pH > 7.20. Contraindicated in raised ICP and sickle cell crisis.
Clinical Significance
- ARDS mortality still 30–45%
- Most common cause is sepsis
- Low tidal volume ventilation saves lives ARDSNet, 2000
- Prone positioning improves survival PROSEVA, 2013
- 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 IBW. 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 Ideal Body Weight (IBW) -NOT actual body weight. Start at 6–8 mL/kg, titrate down to 6 mL/kg. SSC, 2021: strong recommendation, high quality evidence.
IBW male = 50 + 2.3 × (height in inches − 60)
IBW 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 IBW. Increase RR to max 35 to maintain minute ventilation.
IBW male = 50 + 2.3 × (height in inches − 60)
IBW 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 IBW. Increase RR to max 35 to maintain minute ventilation.
Plateau Pressure
Keep Pplat ≤ 30 cmH₂O SSC, 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.
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:
ARDSNet Higher PEEP / FiO₂ Table (moderate-severe):
Target: SpO₂ 88–95% or PaO₂ 55–80 mmHg.
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 |
| 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 |
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/day PROSEVA, 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.
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). If NMBAs used, ensure adequate sedation and analgesia.
SSC, 2021: suggests intermittent NMBA boluses over continuous infusion (weak recommendation, moderate evidence). Overall, NMBAs reduce barotrauma (RR 0.55). If NMBAs used, ensure adequate sedation and analgesia.
Recruitment Maneuvers
SSC, 2021: suggests traditional recruitment maneuvers (sustained CPAP 30–40 cmH₂O × 30–40 sec) in moderate-severe ARDS -improved 28-day mortality (RR 0.79).
AVOID incremental PEEP titration recruitment -ART, 2017: increased 28-day mortality (RR 1.12). SSC, 2021: strong recommendation against.
🔄 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. 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.
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.
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. |
| High-frequency oscillation (HFOV) | Increased mortality. Trial stopped early. OSCILLATE, 2013 |
| Incremental PEEP recruitment | Increased 28-day mortality (RR 1.12). ART, 2017 |
| IV beta-agonists (salbutamol) | 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. 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 IBW -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 IBW), 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 IBW), PEEP 12, FiO2 0.7. Pplat 28, driving pressure 16.
Management:
- Lung-protective ventilation: TV 6 mL/kg IBW, Pplat ≤ 30 ARDSNet, 2000
- 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 IBW), 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
- Optimize HF management: afterload reduction, cardiology consult
- Daily SBT when oxygenation improves
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 IBW 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).
- Plateau pressure -perform inspiratory hold. Target ≤ 30 cmH₂O.
- Driving pressure (Pplat − PEEP) -target < 15 cmH₂O. Strongest independent predictor of mortality Driving Pressure Meta-Analysis, 2015.
- Tidal volume -confirm 6 mL/kg IBW. Recalculate if height was incorrectly entered.
- Static compliance = Vt / (Pplat − PEEP). Normal ~50–80 mL/cmH₂O. In ARDS typically 20–40.
- SpO₂ target -88–95%. Avoid hyperoxemia ICU-ROX, 2020: conservative O₂ therapy may benefit; liberal O₂ offers no advantage.
- Fluid balance -calculate 24h net. Target even or negative after resuscitation FACTT, 2006.
Daily Checklist (ICU Rounds)
- ABG with P/F ratio
- Vent settings review: TV (mL/kg IBW), RR, FiO₂, PEEP, Pplat, driving pressure
- Sedation assessment: RASS score, daily awakening trial eligibility
- Spontaneous breathing trial (SBT) eligibility if improving
- Prone positioning: hours completed, plan for next cycle if P/F < 150
- Fluid balance: I/O, weight, diuretic needs
- DVT prophylaxis, stress ulcer prophylaxis (if high-risk SUP-ICU, 2018), HOB ≥ 30°
- Nutrition: enteral preferred, start within 48h SSC, 2021
- Source control: is the ARDS precipitant being treated?
When to Escalate
- Worsening P/F despite optimal PEEP + prone → ECMO evaluation
- P/F < 80 on FiO₂ 1.0 → emergent ECMO referral
- pH < 7.15 despite max RR and permissive hypercapnia → ECMO or iNO as bridge
- Pplat > 30 despite TV 4 mL/kg → consider ECMO, rule out tension PTX or abdominal compartment syndrome
- New hemodynamic instability → rule out tension PTX, PE, auto-PEEP, RV failure from high PEEP
- Barotrauma (subcutaneous emphysema, pneumomediastinum, PTX) → reduce PEEP/TV, chest tube if indicated
Weaning Readiness Criteria
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.
- Barotrauma -pneumothorax, pneumomediastinum, subcutaneous emphysema. Risk increases with Pplat > 30.
- 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
Diagnosis
P/F < 300, bilateral opacities, acute onset ≤ 1 week, not explained by cardiac failure. Berlin criteria (2012). PEEP ≥ 5 required.
#1 Intervention
Lung-protective ventilation: TV 6 mL/kg IBW, Pplat ≤ 30, driving pressure < 15. ARDSNet, 2000: 22% mortality reduction. The only proven mortality-reducing strategy.
Prone Position
P/F < 150 → prone ≥ 16 hrs/day. PROSEVA, 2013: 28-day mortality 16% vs 32.8%. SSC, 2021: strong rec for > 12h/day. Do not delay.
Fluids
Conservative after resuscitation. FACTT, 2006: ~2.5 fewer vent days, no renal harm. Target even or negative fluid balance.
NMBAs
SSC, 2021: intermittent boluses preferred over infusion. ACURASYS, 2010 vs ROSE, 2019: avoid deep sedation; light sedation + PRN boluses.
Escalation
P/F < 80 or pH < 7.15 → VV-ECMO EOLIA, 2018. Refer early to experienced centers. Avoid: HFOV OSCILLATE, 2013, iNO, surfactant.
RoundsRx Licensed Content - Unauthorized Use Prohibited📄 One Pager
ICU · Ventilator · One Pager
ARDS
Low tidal volumes save lives. Prone early. Keep the lungs small and protected. Everything else is supportive.
📋 Berlin Criteria -All 4 Required
- Acute onset ≤ 1 week of clinical insult
- Bilateral opacities on CXR/CT
- Not explained by cardiac failure/fluid overload
- P/F < 300 with PEEP ≥ 5
📊 Severity
MildP/F 200–300 · ~27% mortality
ModerateP/F 100–200 · ~32% mortality
SevereP/F < 100 · ~45% mortality
🫁 Lung-Protective Ventilation ARDSnet 2000
1
Tidal volume: 6 mL/kg IBW (NOT actual weight). Reduce to 4 mL/kg if Pplat > 30.
2
Plateau pressure: ≤ 30 cmH₂O. Driving pressure: ≤ 15 cmH₂O (Pplat − PEEP).
3
PEEP: Per ARDSnet table. Higher PEEP for more severe disease.
4
Prone position if P/F < 150 → ≥ 16h/day PROSEVA 2013 -mortality halved
5
Conservative fluids after resuscitation -target even/negative balance FACTT 2006
6
ECMO if P/F < 80 or pH < 7.15 despite optimal settings EOLIA 2018
💊 Key Drugs
Propofol5–50 mcg/kg/min
Fentanyl25–200 mcg/hr
Cisatracurium bolus0.1–0.2 mg/kg PRN
FurosemideEven/negative balance
Dexa (COVID only)6 mg/d × 10d
🚫 Does NOT Work
- HFOV OSCILLATE, 2013
- Inhaled nitric oxide
- Routine steroids (non-COVID)
- Surfactant (adults)
- Incremental PEEP recruit ART, 2017
- IV salbutamol BALTI-2, 2012
⚠️ Pitfalls
- High TV "for comfort"
- Delaying prone positioning
- Fluid overload post-resus
- Not calculating IBW
- Deep sedation without indication
- Late ECMO referral
Rounds · ICU / Ventilator
ARDSNet 2000 · PROSEVA 2013 · FACTT 2006 · SSC 2021
ICUVentilator
Airway & Ventilator Management
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.
🔍 Overview -Airway Decision-Making
Indications for Intubation
- Airway protection -GCS ≤ 8, inability to handle secretions, impending obstruction
- Hypoxemic respiratory failure -SpO₂ < 90% despite high-flow O₂, P/F < 200
- Hypercapnic respiratory failure -rising PaCO₂ with acidosis (pH < 7.25), fatigue
- 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.
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 IBW
- Rate (RR) -set respiratory rate
- FiO₂ -fraction of inspired oxygen (0.21–1.0)
- PEEP -positive end-expiratory pressure in cmH₂O
- Peak pressure (Ppeak) -total pressure to deliver breath (airway resistance + alveolar)
- Plateau pressure (Pplat) -alveolar distension pressure (inspiratory hold). Target ≤ 30.
- Driving pressure = Pplat − PEEP. Target ≤ 15. Strong predictor of ARDS mortality.
- P/F ratio = PaO₂ ÷ FiO₂ -oxygenation index
- SpO₂ target -88–95% in ARDS; 94–98% otherwise
💨 Oxygen Delivery Devices
Escalation Ladder -Low Flow to High Flow
Rule of thumb: Each 1 L/min of nasal cannula adds ~4% FiO₂ above room air (21%). So 2L NC ≈ 28%, 4L ≈ 36%, 6L ≈ 44%. This breaks down above 6L.
| Device | Flow Rate | FiO₂ Delivered | Best For | ⚠️ Limitations |
|---|---|---|---|---|
| Nasal Cannula (NC) | 1–6 L/min | 24–44% | Mild hypoxemia. Stable patients. Most common starting point. | ⚠️ Uncomfortable > 6L (dries mucosa). Unreliable FiO₂ -depends on patient's minute ventilation and mouth breathing. |
| Simple Face Mask | 5–10 L/min | 35–55% | Moderate hypoxemia. Short-term use (ED, post-op). | ⚠️ Must run ≥ 5 L/min to prevent CO₂ rebreathing. Claustrophobic. Can't eat/talk well. |
| Venturi Mask | 4–12 L/min | Precise: 24%, 28%, 31%, 35%, 40%, 50% | COPD patients -need precise low FiO₂ (24–28%) to avoid suppressing hypoxic drive. Color-coded adapters. | ⚠️ Max 50% FiO₂. Bulky. Used mainly for COPD. |
| Non-Rebreather (NRB) | 10–15 L/min | 60–90% | Severe hypoxemia. Pre-oxygenation before intubation. CO poisoning. Trauma. | ⚠️ Reservoir bag must stay inflated. Not truly 100% -room air mixes around mask. If patient needs NRB → consider escalation. |
| High-Flow Nasal Cannula (HFNC) | 20–60 L/min | 21–100% (titratable) | Hypoxemic respiratory failure, post-extubation, immunocompromised (avoid intubation), pre-oxygenation. Delivers heated humidified O₂. | ⚠️ Generates ~1 cmH₂O PEEP per 10 L/min (so 60L ≈ 6 cmH₂O). Patient must breathe spontaneously. If still desatting on HFNC 60L/100% → intubate. |
When to Escalate
1
NC 1–6L -SpO₂ still < 92% → escalate
2
Simple mask / NRB 10–15L -SpO₂ still < 92% or work of breathing increasing → escalate
3
HFNC 40–60L -if SpO₂ < 92% on 60L/100% FiO₂, or RR > 30, or accessory muscle use → next step
4
NIV (BiPAP/CPAP) -if COPD exacerbation or cardiogenic pulmonary edema → try NIV before intubation
5
Intubation + Mechanical Ventilation -failing all above, declining mental status, unable to protect airway
⚠️ ROX Index (HFNC failure prediction): ROX = (SpO₂/FiO₂) ÷ RR. Check at 2, 6, 12 hours. ROX < 3.85 at 6h → high risk of HFNC failure → prepare for intubation. ROX > 4.88 → likely safe to continue HFNC.
🌬️ Non-Invasive Ventilation (NIV)
CPAP vs BiPAP
| CPAP | BiPAP | |
|---|---|---|
| What it does | Single continuous pressure (like PEEP) | Two pressures: IPAP (inhale) + EPAP (exhale) |
| Helps with | Oxygenation only -splints airways open, recruits alveoli | Both oxygenation AND ventilation -IPAP augments tidal volume (blows off CO₂), EPAP = PEEP |
| Best for | Cardiogenic pulmonary edema, OSA | COPD exacerbation (hypercapnic failure), obesity hypoventilation, neuromuscular weakness |
| Typical settings | CPAP 5–10 cmH₂O | IPAP 10–20 / EPAP 5–8 cmH₂O. Start IPAP 10, EPAP 5. Titrate IPAP up by 2 q15–30 min for CO₂. |
| Pressure support | None (single pressure) | PS = IPAP − EPAP. Higher PS = more ventilatory support. PS of 10 cmH₂O is moderate support. |
Indications for NIV
- COPD exacerbation with respiratory acidosis (pH < 7.35, PaCO₂ > 45) -strongest evidence, reduces intubation by 65% Brochard, 1995
- Cardiogenic pulmonary edema -CPAP or BiPAP both work. Reduces preload + afterload + recruits flooded alveoli. 3CPO, 2008
- Post-extubation -prophylactic NIV in high-risk patients reduces reintubation
- Immunocompromised with respiratory failure -try NIV/HFNC first to avoid vent-associated infections
- Palliative / DNI patients -ceiling of care when intubation is not desired
🚫 NIV Contraindications: Arrest · GCS ≤ 8 · Vomiting/aspiration risk · Shock · Facial trauma · Airway obstruction · Uncooperative
▶ 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.
| Setting | What It Controls | How to Titrate | Think of It As |
|---|---|---|---|
| EPAP | Oxygenation (splints alveoli open, recruits collapsed lung) | 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.
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.
ABG on arrival: pH 7.22, PaCO₂ 78, PaO₂ 52, HCO₃ 30 (acute-on-chronic hypercapnic respiratory failure).
Step 1 (Time 0): Start BiPAP IPAP 10 / EPAP 5 (PS = 5), FiO₂ 50%.
→ After 15 min: RR 28, SpO₂ 89%. Still distressed. CO₂ not moving.
Step 2 (Time 15 min): ↑ IPAP to 14 / EPAP 5 (PS = 9). Keep FiO₂ 50%.
→ After 30 min: RR 24, SpO₂ 91%. Patient visibly more comfortable. Able to speak in short sentences.
Step 3 (Time 1 hour): Repeat ABG: pH 7.28, PaCO₂ 62, PaO₂ 68. pH improving, CO₂ coming down. ↑ IPAP to 16 / EPAP 5 (PS = 11).
Step 4 (Time 2 hours): ABG: pH 7.32, PaCO₂ 55, PaO₂ 72. RR 20, SpO₂ 93%. BiPAP is working. Intubation avoided.
Overnight: Continue BiPAP. Wean FiO₂ to 35%. Give Ipratropium/Albuterol (DuoNeb) nebs q4h, Methylprednisolone (Solu-Medrol) 125 mg IV, Azithromycin (Zithromax) 500 mg IV. Next AM: ABG 7.38 / 48 / 78. Trial off BiPAP → tolerates nasal cannula. Extubation avoided.
→ After 15 min: RR 28, SpO₂ 89%. Still distressed. CO₂ not moving.
Step 2 (Time 15 min): ↑ IPAP to 14 / EPAP 5 (PS = 9). Keep FiO₂ 50%.
→ After 30 min: RR 24, SpO₂ 91%. Patient visibly more comfortable. Able to speak in short sentences.
Step 3 (Time 1 hour): Repeat ABG: pH 7.28, PaCO₂ 62, PaO₂ 68. pH improving, CO₂ coming down. ↑ IPAP to 16 / EPAP 5 (PS = 11).
Step 4 (Time 2 hours): ABG: pH 7.32, PaCO₂ 55, PaO₂ 72. RR 20, SpO₂ 93%. BiPAP is working. Intubation avoided.
Overnight: Continue BiPAP. Wean FiO₂ to 35%. Give Ipratropium/Albuterol (DuoNeb) nebs q4h, Methylprednisolone (Solu-Medrol) 125 mg IV, 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. |
| Higher EPAP needed | Abdominal mass compresses diaphragm → atelectasis → V/Q mismatch → hypoxemia | 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.
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.
• 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.
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.
3–5 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.
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.
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).
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).
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.
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). | ⚠️ Psychosis/schizophrenia (emergence reactions). Increases secretions -give glycopyrrolate. |
| Propofol (Diprivan) | GABA-A agonist | 1.5–2.5 mg/kg IV push | 15–30 sec | 5–10 min | Status epilepticus (anticonvulsant), elevated ICP (lowers ICP). | ⚠️ Causes significant hypotension -avoid in shock, hypovolemia. Egg/soy allergy (controversial). |
| Midazolam (Versed) | GABA-A agonist (benzo) | 0.1–0.3 mg/kg IV push | 1–2 min | 15–30 min | Rarely used for RSI (slower onset). Backup option. Provides amnesia. | ⚠️ Hypotension. Slower onset than etomidate/ketamine. Can reverse with flumazenil. |
| PARALYTICS (NEUROMUSCULAR BLOCKERS) | ||||||
| Succinylcholine (Anectine) | Depolarizing NMB -mimics ACh, sustained depolarization → paralysis | 1–1.5 mg/kg IV push | 30–45 sec | 6–10 min | Fastest onset + shortest duration. Good when you need to quickly reassess neuro status (e.g., stroke). | ⚠️ Hyperkalemia (burns > 48h, crush injury, denervation, renal failure with K⁺ > 5.5). Malignant hyperthermia (personal/family history). Myasthenia gravis. |
| Rocuronium (Zemuron) | 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.
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)
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)
⚙️ Ventilator Modes Explained
▶ Ventilator Modes Explained — AC, PC, SIMV, PSV, APRV (tap to expand)
Every vent mode answers two questions: (1) What triggers a breath? (patient or machine), (2) What's guaranteed -volume or pressure?
| Mode | How It Works | You Set | What Varies | Best For | ⚠️ Watch For |
|---|---|---|---|---|---|
| AC/VC Assist Control / Volume Control | Every breath (patient-triggered or machine-triggered) delivers a set tidal volume. | TV, RR, FiO₂, PEEP, flow rate | Pressure (Ppeak varies with compliance/resistance) | Most common mode. Default for most intubations. ARDS (guarantees 6 mL/kg TV). | ⚠️ If compliance drops → pressures rise → barotrauma. Watch Pplat. |
| AC/PC Assist Control / Pressure Control | Every breath delivers a set pressure for a set inspiratory time. | Pressure, I-time, RR, FiO₂, PEEP | Tidal volume (varies with compliance) | When you want to limit pressures strictly. Neonatal/pediatric. Some ARDS protocols. | ⚠️ If compliance worsens → TV drops → hypoventilation. Must monitor TV closely. |
| SIMV Synchronized Intermittent Mandatory Ventilation | Delivers set number of mandatory breaths. Patient can take extra breaths on their own (unsupported or with PS). | TV, RR, FiO₂, PEEP, PS level | Patient's spontaneous breaths are variable | Weaning mode -gradually reduce mandatory rate as patient takes over. | ⚠️ Increases work of breathing if PS too low on spontaneous breaths. Largely fallen out of favor -SBT preferred for weaning. |
| PSV Pressure Support Ventilation | Patient triggers every breath. Vent augments each breath with set pressure support. | PS level, FiO₂, PEEP | TV and RR (entirely patient-driven) | SBT (PS 5–8 cmH₂O), weaning assessment, awake cooperative patients. | ⚠️ 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 IBW) | 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.
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.
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. |
| PaO₂ 120, FiO₂ 1.0 | Over-oxygenating | ↓ FiO₂ (wean to target SpO₂ 92–96%) | Hyperoxia harms: ↑ mortality in cardiac arrest, stroke, MI. Wean FiO₂ aggressively. |
The Memory Trick
🔵
O₂ = FiO₂ + PEEP
Escalation: FiO₂ → PEEP → Prone → iNO → ECMO
🔴
CO₂ = RR × TV
"How much air am I moving?"
⚠️ 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.
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
> 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. | PaO₂ < 60 PaCO₂ normal or low | Pneumonia, ARDS, pulmonary edema, PE, pulmonary fibrosis, atelectasis | 🔵 FiO₂ + PEEP → prone → iNO → ECMO |
| Type 2 | Hypercapnic | Failure of ventilation -can't move enough air to clear CO₂. Pump failure (muscles, drive, mechanics). | PaCO₂ > 50 pH < 7.35 PaO₂ may be low too | COPD, asthma, obesity hypoventilation, neuromuscular disease (GBS, MG, ALS), drug overdose (opioids), chest wall deformity | 🔴 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, massive 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 IBW | 6 mL/kg IBW | 6–8 mL/kg IBW |
| 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
- Fix: suction, reposition head, bite block
P -Pneumothorax
- Tension pneumothorax: absent breath sounds + tracheal deviation + hypotension
- Fix: needle decompression NOW (2nd ICS, MCL or 4th ICS, anterior axillary line) then chest tube. Do NOT wait for CXR if hemodynamically unstable.
E -Equipment
- Vent malfunction, circuit disconnect, O₂ supply failure
- Fix: disconnect from vent → manually bag the patient → troubleshoot equipment
High Peak, Normal Plateau
Peak – Plateau > 10 cmH₂O → airway resistance problem (mucus plug, bronchospasm, kinked tube). Treat: suction, bronchodilators, reposition.
High Peak AND High Plateau
Both elevated → decreased compliance problem (worsening ARDS, pneumothorax, pulmonary edema, pneumonia). Check CXR, assess clinically.
🧪 Workup
Workup
- ABG pre/post intubation
- CXR -ETT 2-4cm above carina
- Plateau pressure -goal <30
- Driving pressure -Pplat−PEEP, goal <15
- Auto-PEEP -expiratory hold
- Peak vs Plateau -high peak + normal plat = airway resistance; both high = compliance problem
🚨 Management
Management
- Lung-protective: TV 6–8 mL/kg IBW, Pplat < 30, driving pressure < 15
- ARDS: TV 6 mL/kg IBW 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. ⚠️ 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. 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.
🔓 Weaning & Extubation
Ventilator Weaning & Extubation
Step 1: Daily Spontaneous Awakening Trial (SAT)
- Stop sedation infusions daily (unless contraindicated: active seizures, alcohol withdrawal, paralytics, elevated ICP)
- Assess: Is patient following commands? Opening eyes? Breathing comfortably?
- Restart sedation at half dose if patient fails (agitation, RR > 35, SpO₂ < 88%, distress)
Step 2: Spontaneous Breathing Trial (SBT)
Perform if SAT passes. Place on minimal vent support (CPAP 5 / PS 5–8) for 30–120 minutes.
SBT readiness criteria: FiO₂ ≤ 40%, PEEP ≤ 8, hemodynamically stable (no/low vasopressors), adequate mental status, intact cough reflex.
Pass criteria -ALL of the following:
- RR < 30, SpO₂ > 90%, TV > 5 mL/kg IBW
- RSBI (Rapid Shallow Breathing Index) = RR ÷ Vt (in L) < 105 -most validated weaning predictor
- No distress, paradoxical breathing, or diaphoresis
- HR and BP within 20% of baseline
Step 3: Extubation Checklist
- Passed SBT ✓
- Airway reflexes intact -strong cough, follows commands
- 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
- Secretion burden manageable (not suctioning > q2h)
- 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.
📋 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 IBW), 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. IBW ~63 kg → TV 6 mL/kg IBW = 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 IBW, 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 IBW. 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 massive 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.
Monitoring -Mechanical Ventilation
| Parameter | Frequency | Target / Action |
|---|---|---|
| ABG | 30 min after any vent change, then q4–6h | pH, PaCO2, PaO2, P/F ratio. Guides FiO2/PEEP (oxygenation) and RR/TV (ventilation) adjustments. |
| Daily SBT assessment | Every morning | 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
Initial Settings
AC/VC, TV 6–8 mL/kg IBW, RR 14–18, FiO₂ 1.0 then wean, PEEP 5
ARDS Settings
TV 6 mL/kg IBW, Pplat ≤ 30, driving pressure ≤ 15, PEEP per ARDSnet table
Acute Deterioration
DOPE: Displacement, Obstruction, Pneumothorax, Equipment. Bag first if in doubt.
Weaning
Daily SAT → SBT. RSBI < 105. Pass both → extubate. Coordinate daily.
High Peak / Normal Plat
Airway resistance problem → suction, bronchodilators, reposition tube
High Peak + High Plat
Compliance problem → pneumothorax, ARDS, pulmonary edema. CXR + assess.
📄 One Pager
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 IBW
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
Rounds · ICU / Ventilator
ARDSnet 2000 · Girard 2008
📣 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.
EMERGENTICU
Cardiogenic Shock
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. |
| Massive PE (~2–3%) | RV failure from acute pressure overload. Not true "pump" failure -it's obstructive. tPA, catheter-directed therapy, or surgical embolectomy. |
| Cardiac tamponade (~1–2%) | Beck's triad: hypotension, JVD, muffled heart sounds. Pulsus paradoxus > 10 mmHg. Emergent pericardiocentesis. |
| Arrhythmia-induced (~1–2%) | Refractory VT/VF, complete heart block, tachycardia-mediated cardiomyopathy. Treat the rhythm -cardioversion, pacing, amiodarone. |
| Takotsubo (~1–2%) | Apical ballooning, post-emotional/physical stress. Often mimics STEMI. Usually recovers in days to weeks. Supportive care. |
| Post-cardiotomy (~2–6%) | Low CO syndrome post-cardiac surgery (CPB-related stunning). Milrinone or dobutamine. IABP/Impella if refractory. |
Recognition -Cold & Wet Profile
- Hypotension (SBP < 90) + cool, clammy extremities
- Mottled skin, cyanosis of peripheries
- Altered mental status (cerebral hypoperfusion)
- Oliguria / anuria (renal hypoperfusion)
- Elevated JVP, S3, pulmonary crackles (elevated filling pressures)
- Lactate > 2 (tissue hypoperfusion)
- Do NOT give aggressive fluids -will worsen pulmonary edema without improving CO
- Do NOT use beta-blockers, calcium channel blockers, or nitrates in acute CS
🧪 Workup & Diagnosis
Immediate Workup
ECHO is the most important early test. Get it immediately -confirms diagnosis, identifies cause, guides management.
- ECG immediately -rule out STEMI (immediate cath lab activation), complete heart block, arrhythmia
- Bedside echo -EF, wall motion abnormalities, tamponade, valvular emergency, RV failure
- 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 PCI SHOCK 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?
Cardiogenic: cold extremities, mottled, elevated JVP, pulmonary edema (crackles), narrow pulse pressure, low-output state. Echo: poor EF, dilated LV. PA catheter: CI < 2.2, PCWP > 15, elevated SVR. Septic: warm extremities (early), bounding pulses, wide pulse pressure, dry lungs, high-output state. Echo: hyperdynamic LV. PA catheter: CI > 2.5, PCWP low/normal, low SVR.
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. (4)
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.
Key findings: Refractory CS despite maximal medical therapy. Worsening multiorgan failure.
Management:
- VA-ECMO as bridge to recovery or transplant
- 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
Definition
SBP < 90 + CI < 2.2 + PCWP > 15. Cold, clammy, low output despite adequate filling pressures.
Most Common Cause
Acute MI (large anterior STEMI). Always get ECG immediately and activate cath lab if STEMI.
Vasopressors
Norepinephrine first. NOT dopamine (arrhythmias). Add vasopressin or epinephrine if refractory.
Inotropes
Dobutamine when MAP adequate but CO still low. Milrinone alternative (avoid if hypotensive).
Key Intervention
Treat the cause. PCI for ACS. Pericardiocentesis for tamponade. Early mechanical circulatory support (MCS) if refractory.
Mortality
40–50%. Early revascularization + mechanical circulatory support (MCS) = best chance. Do not delay PCI for "stabilization."
📄 One Pager
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
- Massive 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 "stabilisation."
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.
4
Emergency PCI if STEMI SHOCK 1999 -early revascularisation reduces 1-year mortality.
5
Mechanical circulatory support -Impella/ECMO if refractory. IABP no longer routine IABP-SHOCK II 2012.
6
Treat the cause: Drain tamponade, pace if heart block, repair valve, treat myocarditis.
💊 Drugs
Norepinephrine (Levophed)0.1–1 mcg/kg/min
Dobutamine (Dobutrex)2–20 mcg/kg/min
Vasopressin (Vasostrict)0.03 u/min
Milrinone (Primacor)0.375–0.75 mcg/kg/min
🚫 Do NOT Use
- Dopamine (↑ arrhythmias)
- Beta-blockers
- CCBs
- Aggressive fluids
- IABP routinely
📊 Differentiating Shock
CO↓↓ (vs ↑ in sepsis)
SVR↑↑ (vs ↓ in sepsis)
PCWP↑↑ (vs low in sepsis)
Rounds · ICU / Cardiology
SHOCK 1999 · IABP-SHOCK II 2012
EMERGENTICU
Hypertensive Emergency
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.
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.
End-Organ Damage to Look For
- Neurologic: Hypertensive encephalopathy (AMS, headache, vision changes), hemorrhagic stroke, ischemic stroke
- Cardiac: Aortic dissection, ACS, acute pulmonary edema
- Renal: AKI, hematuria, proteinuria (hypertensive nephrosclerosis)
- Ophthalmologic: Papilledema, retinal hemorrhages (fundoscopy)
- Hematologic: Microangiopathic hemolytic anemia (MAHA), TTP-like picture
- OB: Eclampsia, HELLP syndrome
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, 2016 INTERACT2, 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.
Swipe for more examples
📋 Case 1 — Hypertensive Emergency Management
- Patient: 52M presents with BP 228/134, headache, blurred vision, chest pain. Cr 2.4 (baseline 1.0). Troponin 0.08. UA: 2+ protein, RBC casts.
- 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.
- Acute pulmonary edema → Nitroglycerin (Nitrostat) drip + furosemide (Lasix).
- 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. | Advanced aortic stenosis | ||||||||||||||||||||||||||||||||||||
| Labetalol (Trandate) | 20–80 mg IV bolus q10min, or 0.5–2 mg/min drip | 5 min | Aortic dissection, stroke, eclampsia | Asthma, severe bradycardia, acute HF | ||||||||||||||||||||||||||||||||||||
| Esmolol (Brevibloc) | 500 mcg/kg bolus, then 50–200 mcg/kg/min | 1–2 min | Aortic dissection (HR control) | Bronchospasm, bradycardia | ||||||||||||||||||||||||||||||||||||
| Sodium Nitroprusside | 0.3–10 mcg/kg/min | Seconds | Hypertensive emergency when other agents fail | Renal failure (cyanide toxicity), elevated ICP, pregnancy | ||||||||||||||||||||||||||||||||||||
| Nitroglycerin (Nitrostat) | 5–200 mcg/min IV | 1–2 min | Pulmonary edema, ACS | Aortic dissection (reflex tachycardia), PDE5 inhibitor use | ||||||||||||||||||||||||||||||||||||
| Hydralazine (Apresoline) | 10–20 mg IV q4–6h | 10–20 min | Eclampsia (if labetalol not available) | Aortic dissection, aortic aneurysm
🧪 Workup
Workup -Hypertensive Emergency
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.
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
Emergency vs Urgency
Emergency = high BP + end-organ damage (CNS, cardiac, renal, eyes). Urgency = high BP alone. Different management entirely.
Exclude First
Aortic dissection -if chest/back pain + high BP. CTA immediately. Requires aggressive reduction and beta-blockade.
BP Reduction Rule
Reduce MAP by ≤ 25% in first hour. Then to 160/100 over next 6 hrs. Except dissection (aggressive) and ischemic stroke (conservative).
Go-To Drug
Nicardipine IV -titratable, reliable, works for most emergencies. Labetalol for dissection/stroke/eclampsia.
Pheo Rule
Alpha-block FIRST (phentolamine), THEN add beta-blocker. Never beta-block first -causes unopposed alpha hypertensive crisis.
Nitroprusside Warning
Risk of cyanide toxicity in renal failure and prolonged use. Also causes elevated ICP. Use only when other agents fail.
📄 One Pager
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
Rounds · ICU
JNC 8 · ACC/AHA Hypertension Guidelines 2017
EMERGENTICUNeurology
Status Epilepticus
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.
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)
- Acute CNS insult: stroke, hemorrhage, encephalitis, meningitis, trauma, tumor
- Metabolic: severe hyponatremia, hypoglycemia, hypocalcemia, uremia
- Toxins/withdrawal: alcohol withdrawal, cocaine, TCAs, isoniazid
- Anoxic brain injury (post-cardiac arrest)
- 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.
🚨 Management
Status Epilepticus Protocol -Time Is Neurons
0–5 Minutes -Stabilize
ABCs, O₂, IV access, cardiac monitor. POC glucose STAT. If hypoglycemic → D50W 50 mL IV. Check temperature (fever → cooling). Place patient safely, do NOT restrain or put anything in mouth.
5 Minutes -Phase 1: Benzodiazepine (First-Line)
IV access available: Lorazepam 0.1 mg/kg IV (max 4 mg), repeat × 1 in 5 min if no response
No IV access: Midazolam 10 mg IM (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.
No IV access: Midazolam 10 mg IM (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.
20 Minutes -Phase 2: Second AED (if benzo fails)
Give ONE of: Levetiracetam 60 mg/kg IV (max 4500 mg) over 10 min -preferred (fewest drug interactions, no respiratory depression) OR Valproate 40 mg/kg IV over 10 min (avoid in liver disease, pregnancy, metabolic disorders) OR Fosphenytoin 20 mg PE/kg IV (slower, cardiac monitoring needed, avoid in liver disease).
ESETT 2019: all three equally effective (~50% seizure termination at 60 min).
ESETT 2019: all three equally effective (~50% seizure termination at 60 min).
40 Minutes -Phase 3: Refractory SE → ICU + Anesthetic
Intubate + continuous EEG.
Options: Propofol 2 mg/kg IV bolus then 1–15 mg/kg/hr drip OR Midazolam 0.2 mg/kg IV bolus then 0.05–2 mg/kg/hr drip OR Ketamine 1.5 mg/kg IV bolus then 1.2–5 mg/kg/hr (NMDA antagonist, neuroprotective, less respiratory depression).
Neurology and/or epilepsy consult. Continuous EEG mandatory to detect NCSE and guide treatment.
Options: Propofol 2 mg/kg IV bolus then 1–15 mg/kg/hr drip OR Midazolam 0.2 mg/kg IV bolus then 0.05–2 mg/kg/hr drip OR Ketamine 1.5 mg/kg IV bolus then 1.2–5 mg/kg/hr (NMDA antagonist, neuroprotective, less respiratory depression).
Neurology and/or epilepsy consult. Continuous EEG mandatory to detect NCSE and guide treatment.
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).
Swipe for more examples
📋 Case 1 — Status Epilepticus Management
- Patient: 28M found seizing in ED, generalized tonic-clonic. Ongoing seizure for 8 minutes. No IV access yet.
- 0-5 min (Stabilize): ABCs, O2, glucose check. Position safely. Time the seizure.
- No IV? → Midazolam (Versed) 10mg IM (RAMPART 2012 -IM midazolam non-inferior to IV lorazepam and faster to administer).
- IV obtained? → Lorazepam (Ativan) 4mg IV over 2 min. May repeat × 1 in 5 min.
- 5-20 min (Established status -benzo failed): Choose ONE:
- Levetiracetam (Keppra) 60mg/kg IV (max 4500mg) over 15 min -no cardiac monitoring needed, no drug interactions
- Fosphenytoin 20mg PE/kg IV over 20 min -requires cardiac monitoring (hypotension, arrhythmia risk)
- Valproate (Depakote) 40mg/kg IV over 10 min -avoid in pregnancy, liver disease
- ESETT 2019: All three equally effective (~45% seizure cessation). Choose based on patient factors.
- >20 min (Refractory status -failed 2 agents): Intubate → continuous IV anesthesia:
- Midazolam drip 0.2mg/kg/hr, propofol (Diprivan) 2-5mg/kg/hr, or pentobarbital
- Continuous EEG monitoring. Target: burst suppression for 24-48h, then slowly wean.
- Post-ictal workup: BMP (Na, glucose, Ca, Mg), tox screen, AED levels, CT head, LP if concern for infection. MRI brain when stable.
📋 Case 2 — Refractory Status Epilepticus
- Patient: 45F with known epilepsy, seizing for 40 minutes. Already received lorazepam 4mg IV × 2 doses and levetiracetam 60 mg/kg IV — still seizing.
- Diagnosis: This is refractory SE — seizure persists after adequate benzodiazepine + second-line AED.
- Next step: Intubation for airway protection + continuous IV anesthetic. Options:
- Midazolam drip: 0.2 mg/kg bolus → 0.1–2 mg/kg/hr infusion
- Propofol drip: 2 mg/kg bolus → 30–200 mcg/kg/min infusion
- Pentobarbital (super-refractory): 5 mg/kg bolus → 1–5 mg/kg/hr
- Monitoring: Connect continuous EEG (cEEG) — you cannot assess seizure cessation clinically once paralyzed/sedated. Target: burst suppression for 24–48h then slowly wean.
- Key lesson: After 2nd-line AED fails = refractory SE. Intubate and start anesthetic drip. Must have continuous EEG — clinical exam is useless once sedated.
📋 Case 3 — Non-Convulsive Status Epilepticus (NCSE)
- Patient: 70M post-cardiac arrest, achieved ROSC but remains obtunded at 24h. No obvious convulsions. Nursing notes "intermittent eye twitching."
- Workup: Continuous EEG ordered → shows electrographic seizures. This is NCSE — the brain is seizing without visible motor activity.
- Incidence: Up to 30% of comatose ICU patients have NCSE. It is extremely common and frequently missed.
- Treatment: IV levetiracetam or lacosamide (less sedating than benzos). If seizures persist → add second AED. Avoid aggressive sedation unless electrographic SE persists.
- Key lesson: Always get EEG on any unexplained altered mental status in ICU. NCSE is common and missed. Eye twitching, lip smacking, or failure to wake up = order EEG.
💊 Medications & Doses
Medications Reference
| Drug | Dose | Phase | Notes |
|---|---|---|---|
| Lorazepam 1ST LINE | 0.1 mg/kg IV, max 4 mg; repeat × 1 | Phase 1 (IV) | First-line if IV access. Respiratory depression risk -have bag-mask ready. |
| 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. |
| Valproate (Depakote) 2ND LINE | 40 mg/kg IV, max 3000 mg over 10 min | Phase 2 | Avoid: liver disease, pregnancy, metabolic disorders (mitochondrial disease). Effective for absence/myoclonic SE. |
| Fosphenytoin 2ND LINE | 20 mg PE/kg IV, max 1500 mg PE | Phase 2 | Cardiac monitoring (hypotension, arrhythmia during infusion). Avoid in liver disease. Give ≤ 150 mg PE/min. |
| 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.< |
📋 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 10 mg IM (no IV) RAMPART, 2012
- Establish IV; if seizure persists, levetiracetam 60 mg/kg IV (max 4500 mg)
- 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 4 mg IV x2 and levetiracetam 4500 mg IV.
Key findings: Failed first-line and second-line agents = refractory SE. SpO2 88%.
Management:
- Intubate for airway protection
- Propofol 2 mg/kg bolus then 30-200 mcg/kg/min, titrate to burst suppression on cEEG
- 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
📋 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 60 mg/kg (less sedating, preferred post-arrest)
- If seizures persist, add lacosamide 200 mg IV or valproate 40 mg/kg IV
- 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
Definition
Seizure ≥ 5 min OR ≥ 2 seizures without return to baseline. Every minute = neuronal death.
Phase 1 (0–20 min)
Lorazepam 0.1 mg/kg IV OR midazolam 10 mg IM (no IV access). Check glucose first.
Phase 2 (20–40 min)
Levetiracetam 60 mg/kg IV (preferred), valproate 40 mg/kg, or fosphenytoin 20 mg PE/kg. All equal ESETT 2019.
Phase 3 (refractory)
Intubate + continuous EEG. Propofol or midazolam infusion. Neurology consult. Find the cause.
Don't Miss
Non-convulsive SE -AMS after seizure + no waking up = EEG immediately.
Cause Hunt
AED levels, glucose, lytes, CT head, LP (if no ICP), toxicology. Anti-NMDA antibodies in young women with encephalopathy.
📄 One Pager
ICU · Neurology · One Pager
Status Epilepticus
Every minute of seizure = neuronal death. Three phases. Benzo first. Levetiracetam second. Intubate + EEG if refractory. Don't miss NCSE.
⏱️ 3-Phase Protocol
0
Immediately: ABCs, glucose, IV access, O₂, monitor. Thiamine before glucose.
1
0–20 min -Benzo: Lorazepam 0.1 mg/kg IV (max 4 mg) OR midazolam 10 mg IM if no IV RAMPART 2012
2
20–40 min -2nd AED: Levetiracetam 60 mg/kg IV (preferred) OR valproate 40 mg/kg OR fosphenytoin 20 mg PE/kg -all equal ESETT 2019
3
> 40 min -Refractory: Intubate + continuous EEG + propofol or midazolam infusion. Neurology consult.
💊 Phase 2 Drugs
Levetiracetam60 mg/kg IV (preferred)
Valproate40 mg/kg IV
Fosphenytoin20 mg PE/kg IV
🔍 Find the Cause
- AED levels (non-adherence)
- Glucose, electrolytes
- CT head → LP
- Toxicology screen
- Anti-NMDA antibodies
⚠️ Don't Miss
- NCSE -AMS after seizure + not waking → EEG now
- Glucose before anything else
- Thiamine before glucose in alcoholic
Rounds · ICU / Neurology
ESETT 2019 · RAMPART 2012
EMERGENTICU / FloorGI
Upper GI Bleed (UGIB)
Bleeding proximal to the ligament of Treitz. Presentation: hematemesis, coffee-ground emesis, melena, or hemodynamic instability. Mortality 2–10%. Resuscitate first, scope second.
🔍 Overview
Causes
Non-Variceal (80%)
- Peptic ulcer disease (most common -40–50%) -H. pylori, NSAIDs, stress
- Mallory-Weiss tear (retching → gastroesophageal junction tear)
- Gastritis / duodenitis
- Dieulafoy lesion (large submucosal artery)
- Upper GI malignancy
Variceal (20%)
- Esophageal varices (portal hypertension from cirrhosis)
- Gastric varices
- Higher mortality, requires different initial management (octreotide + antibiotics)
Risk Stratification -Glasgow-Blatchford Score
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 2015 Villanueva, 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).
- NPO. Proton pump inhibitor: pantoprazole (Protonix) 80mg IV bolus → 8mg/hr drip.
- 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).
- Restrictive transfusion: target Hgb 7. Avoid over-resuscitation — raises portal pressure → rebleeding.
- 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. |
| PRBCs | Transfuse to Hgb 7–9 g/dL | Hemodynamically significant bleed | Restrictive transfusion (target Hgb 7) TRIGGER 2015. Exception: ACS/active cardiac disease -target 8–9. |
📋 On Rounds
On Rounds
📋 Sample Presentation
"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.
Key findings: HR 128, BP 78/44, Temp 37.8°C, SpO2 94%. Distended abdomen with fluid wave. Hgb 6.2, platelets 62K, INR 1.8, Cr 1.9, lactate 5.1. Glasgow-Blatchford score: 17 (high risk).
Management:
- 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
- Return precautions: hematemesis, melena, lightheadedness, syncope
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 -Cardiogenic Shock
| 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
Immediate
2 large-bore IVs, resuscitate, airway (intubate if massive bleed/AMS), type & cross, call GI early.
Non-Variceal
IV pantoprazole 80 mg bolus → 8 mg/hr. EGD within 24h (12h if unstable). Treat H. pylori.
Variceal
Octreotide drip + ceftriaxone immediately. EGD with band ligation. TIPS if refractory.
Transfusion
Restrictive strategy: transfuse to Hgb 7–9. Higher targets in ACS. Correct coagulopathy before scope.
BUN:Cr Clue
BUN:Cr > 20 suggests UGIB (blood digested as protein, creatinine unchanged)
Pitfall
Transfusing aggressively in variceal bleed worsens portal hypertension and increases rebleed risk. Restrictive strategy is especially critical here.
📄 One Pager
GI · ICU · One Pager
Upper GI Bleed
Resuscitate first, scope second. Variceal vs non-variceal drives management. Octreotide + ceftriaxone in any cirrhotic. Restrictive transfusion saves lives.
🩸 Non-Variceal (80%)
- PUD (most common)
- Mallory-Weiss tear
- Rx: IV pantoprazole 80 mg → 8 mg/hr
- EGD within 24h (12h if unstable)
- Treat H. pylori
🫀 Variceal (20%) -Higher Mortality
- Portal hypertension (cirrhosis)
- Start immediately: Octreotide 50 mcg → 50 mcg/hr
- Antibiotics: Ceftriaxone 1g IV daily × 7 days
- EGD with band ligation
- TIPS if refractory
🔬 BUN:Cr Clue
- BUN:Cr > 20:1
- Blood digested as protein
- Confirms UGIB source
🩺 Transfusion
- Target Hgb 7–9 TRIGGER 2015
- Restrictive = better survival
- ACS: target Hgb 8–9
⚠️ Pitfalls
- Over-transfusing variceal bleed
- No antibiotics in cirrhotic
- Scoping unstable patient
Rounds · GI / ICU
TRIGGER 2015 · BSG Guidelines 2021
EMERGENTICU
Post-Cardiac Arrest Care (ROSC)
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.
Reversible Causes of Cardiac Arrest -The H's & T's
Mnemonic: 6 H's and 6 T's -Run through every H and T systematically during and after every arrest. If you don't find the cause, you can't fix it.
| H's | Clue / How to Find | Fix |
|---|---|---|
| Hypovolemia | Flat IVC on echo, trauma, GI bleed | Volume resuscitation, blood products, source control |
| Hypoxia | SpO₂, cyanosis, airway obstruction | Secure airway, ventilate, confirm ETT placement |
| Hydrogen ion (acidosis) | ABG -pH < 7.1, severe DKA, renal failure, sepsis | Bicarb, treat underlying cause |
| Hypo/Hyperkalemia | ECG (peaked T's, wide QRS, sine wave), BMP | Calcium, insulin/glucose, dialysis (hyperK). IV KCl, Mg (hypoK). |
| Hypothermia | Core temp < 30°C, exposure history, near-drowning | Active rewarming. "Not dead until warm and dead." |
| Hypoglycemia | Fingerstick glucose, diabetic on insulin/sulfonylureas, altered mental status pre-arrest | D50W 25–50 mL IV push (1–2 amps). Recheck glucose q15min. |
| T's | Clue / How to Find | Fix |
|---|---|---|
| Tension pneumothorax | Absent breath sounds, tracheal deviation, hypotension, distended neck veins | Needle decompression (2nd ICS MCL) → chest tube |
| Tamponade (cardiac) | Distended neck veins, muffled heart sounds, hypotension (Beck's triad). Echo: effusion + RV collapse. | Pericardiocentesis (subxiphoid, echo-guided) |
| Toxins | Med hx, pill bottles, toxidrome. Common: TCA, digoxin, beta-blockers, CCBs, opioids. | Specific antidotes. Bicarb (TCA), digibind, glucagon (BB), high-dose insulin (CCB), naloxone. |
| Thrombosis -PE | RV dilation on echo, history of immobility/DVT, PEA arrest | tPA 50mg IV push (if massive PE during arrest), surgical/IR embolectomy |
| Thrombosis -MI | 12-lead ECG: STEMI or new LBBB, regional wall motion abnormality on echo | Emergent cath lab -even during CPR (in select patients) |
| Trauma | Mechanism of injury, external signs of hemorrhage, unstable pelvis, distended abdomen | Massive transfusion protocol, surgical intervention, pelvic binder. Address hemorrhagic shock. |
Immediately post-ROSC: ECG + echo. STEMI → cath lab immediately (even if neurologically devastated). Echo → wall motion, RV dilation (PE), tamponade, EF.
🔍 Overview
Post-Cardiac Arrest Syndrome
After ROSC, four simultaneous processes occur:
- Post-arrest brain injury -cerebral edema, impaired autoregulation, seizures (30–40% of arrests)
- Post-arrest myocardial dysfunction -global systolic/diastolic dysfunction (peaks at 24–48 hrs, often reversible)
- Systemic ischemia/reperfusion injury -cytokine storm, coagulopathy, multi-organ dysfunction
- Precipitating cause -must identify and treat (ACS, PE, electrolytes, toxins)
Reversible Causes of Cardiac Arrest -The H's & T's
Mnemonic: 6 H's and 6 T's -Run through every H and T systematically during and after every arrest. If you don't find the cause, you can't fix it.
| H's | Clue / How to Find | Fix |
|---|---|---|
| Hypovolemia | Flat IVC on echo, trauma, GI bleed | Volume resuscitation, blood products, source control |
| Hypoxia | SpO₂, cyanosis, airway obstruction | Secure airway, ventilate, confirm ETT placement |
| Hydrogen ion (acidosis) | ABG -pH < 7.1, severe DKA, renal failure, sepsis | Bicarb, treat underlying cause |
| Hypo/Hyperkalemia | ECG (peaked T's, wide QRS, sine wave), BMP | Calcium, insulin/glucose, dialysis (hyperK). IV KCl, Mg (hypoK). |
| Hypothermia | Core temp < 30°C, exposure history, near-drowning | Active rewarming. "Not dead until warm and dead." |
| Hypoglycemia | Fingerstick glucose, diabetic on insulin/sulfonylureas, altered mental status pre-arrest | D50W 25–50 mL IV push (1–2 amps). Recheck glucose q15min. |
| T's | Clue / How to Find | Fix |
|---|---|---|
| Tension pneumothorax | Absent breath sounds, tracheal deviation, hypotension, distended neck veins | Needle decompression (2nd ICS MCL) → chest tube |
| Tamponade (cardiac) | Distended neck veins, muffled heart sounds, hypotension (Beck's triad). Echo: effusion + RV collapse. | Pericardiocentesis (subxiphoid, echo-guided) |
| Toxins | Med hx, pill bottles, toxidrome. Common: TCA, digoxin, beta-blockers, CCBs, opioids. | Specific antidotes. Bicarb (TCA), digibind, glucagon (BB), high-dose insulin (CCB), naloxone. |
| Thrombosis -PE | RV dilation on echo, history of immobility/DVT, PEA arrest | tPA 50mg IV push (if massive PE during arrest), surgical/IR embolectomy |
| Thrombosis -MI | 12-lead ECG: STEMI or new LBBB, regional wall motion abnormality on echo | Emergent cath lab -even during CPR (in select patients) |
| Trauma | Mechanism of injury, external signs of hemorrhage, unstable pelvis, distended abdomen | Massive transfusion protocol, surgical intervention, pelvic binder. Address hemorrhagic shock. |
Immediately post-ROSC: ECG + echo. STEMI → cath lab immediately (even if neurologically devastated). Echo → wall motion, RV dilation (PE), tamponade, EF.
🚨 Management
Post-Arrest Bundle -ICU Protocol
Immediately Post-ROSC
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%.
Hemodynamics
Target MAP ≥ 65–70 mmHg. Norepinephrine first-line. Dobutamine if post-arrest myocardial dysfunction. Avoid hypotension (worsens brain injury). Avoid aggressive fluid loading in pulmonary edema.
Targeted Temperature Management (TTM)
Target core temperature 32–36°C for ≥ 24 hours in comatose survivors. TTM-2 2021: 33°C vs 37.5°C -no difference in survival. Current evidence: prevent fever (T > 37.7°C) is mandatory. Active cooling to 33°C still widely practiced and reasonable in deep coma. Use cooling blankets, Arctic Sun, or invasive methods.
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.
💊 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. (3)
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.
Workup: SSEP — bilateral N20 waves absent (strongest predictor of poor neurologic outcome). MRI brain ordered. NSE level elevated. CT head: no hemorrhage, diffuse cerebral edema.
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 -Hypertensive Emergency
| 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
Immediate
ECG → STEMI → cath lab now. Echo → find reversible cause. Avoid hyperoxia, avoid hypocapnia.
Hemodynamics
MAP ≥ 65–70. NE first-line. Add dobutamine for low EF. Post-arrest myocardial dysfunction is often reversible at 48–72h.
TTM
Prevent fever (> 37.7°C) is mandatory. Cooling to 33°C reasonable in deep coma. 24 hours minimum. Rewarm slowly.
Seizures
30–40% have post-arrest seizures. Continuous EEG for comatose patients. Treat aggressively if detected.
Prognostication
Wait ≥ 72h post-rewarming. Multimodal: exam + SSEP + EEG + MRI + NSE. Never base on one test alone.
H's & T's
Always find the cause. Hypovolemia, Hypoxia, Hydrogen ion, Hypo/hyperK, Hypothermia, Hypoglycemia, Tension PTX, Tamponade, Toxins, Thrombosis (PE), Thrombosis (MI), Trauma.
RoundsRx Licensed Content - Unauthorized Use Prohibited📄 One Pager
ICU · One Pager
Post-Cardiac Arrest Care (ROSC)
ROSC is the beginning, not the end. ECG → echo → TTM → avoid hyperoxia → find the cause. Don't prognose for 72h post-rewarming.
❤️ Post-ROSC Bundle
1
12-lead ECG -STEMI → cath lab immediately (even if comatose)
2
Bedside echo -EF, wall motion, tamponade, RV dilation (PE)
3
Avoid hyperoxia -target SpO₂ 94–98%, NOT 100% (free radical injury) Kilgannon 2010
4
MAP ≥ 65–70 -NE first-line. Dobutamine if post-arrest low EF.
5
TTM: Prevent fever > 37.7°C mandatory. 33°C reasonable in deep coma TTM-2 2021
6
Continuous EEG -30–40% have post-arrest seizures (NCSE)
🔠 6 H's & 6 T's
- Hypovolemia, Hypoxia
- Hydrogen ion, Hypo/hyperK
- Hypothermia, Hypoglycemia
- Tension PTX, Tamponade
- Toxins, Thrombosis (PE/MI)
- Trauma
🧠 Prognostication
- Wait ≥ 72h post-rewarming
- Neuro exam + SSEP + EEG
- MRI brain + NSE levels
- No single test is definitive
⚠️ Pitfalls
- Hyperoxia (FiO₂ 1.0 left on)
- Early prognostication
- Missing post-arrest NCSE
- Delaying PCI for STEMI
Rounds · ICU
TTM-2 2021 · AHA Post-Arrest Guidelines 2020
🧪 Workup
Workup -Post-Cardiac Arrest Care (ROSC)
Workup for Post-Cardiac Arrest Care (ROSC): Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
EMERGENTICU / FloorGI / Hepatology
Hepatic Encephalopathy & Acute Liver Failure
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.
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
- Also: Constipation, Dehydration, Electrolyte disturbance (hypokalemia → alkalosis → ↑NH3)
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.
Causes of Acute Liver Failure
- Acetaminophen toxicity (most common in US -50%)
- Viral hepatitis (HAV, HBV, HEV)
- Drug-induced (isoniazid, amoxicillin-clavulanate, NSAIDs)
- Autoimmune hepatitis
- Ischemic hepatitis ("shock liver")
- Wilson's disease, Budd-Chiari, pregnancy-related (AFLP, HELLP)
🧪 Workup & Diagnosis
Workup
For Hepatic Encephalopathy
- 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 RFHE 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.
- Zinc 220mg PO daily -zinc deficiency impairs urea cycle, worsening ammonia metabolism.
- 🔄 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.
- TIPS — if recent, may need revision.
- Treatment:
- Lactulose titrated to 3-4 BMs/day (NOT diarrhea — diarrhea causes dehydration → worsens HE).
- Rifaximin 550mg BID.
- Treat the precipitant.
- Consider zinc supplementation (cofactor in urea cycle).
- 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%. 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). (3)
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
- Add rifaximin 550 mg BID (especially if recurrent episodes) Bass, 2010
- 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."
Monitoring -Hepatic Encephalopathy
| Parameter | Frequency | Target / Action |
|---|---|---|
| West Haven grade | q4–8h (more frequent if worsening) | Track mental status: orientation, asterixis, somnolence. Grade 3–4 → consider ICU for airway protection. |
| Asterixis | Each assessment | Negative myoclonus ("liver flap"). Presence confirms HE. Disappearance suggests improvement. |
| Orientation | Each assessment | 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
HE First Move
Find the precipitant. Tap ascites (rule out SBP). Treat infection. Lactulose to 2–3 stools/day.
Medications
Lactulose (first-line). Rifaximin 550 mg BID added for recurrent/refractory HE.
Airway
Grade 3–4 HE → intubate for airway protection especially before procedures.
ALF
ICU + NAC (especially for APAP) + transplant evaluation immediately. Do not delay listing.
SBP Rule
Always tap ascites in new/worsening HE. PMN > 250 = SBP. Treat with cefotaxime + albumin.
Common Pitfall
Giving FFP in ALF (obscures prognosis). Not tapping ascites. Giving lactulose without finding precipitant.
📄 One Pager
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
- Most commonly missed precipitant
💊 HE Treatment
Lactulose25–30g q1–2h → 2–3 stools/day
Rifaximin550 mg PO BID RFHE 2010
Treat precipitantMost important step
🆘 ALF Management
- ICU admission
- NAC (especially APAP)
- Transplant evaluation NOW
- Do NOT correct INR prophylactically
⚠️ Pitfalls
- Not tapping ascites
- FFP prophylactically (obscures prognosis)
- Grade 3–4 → intubate early
- Lactulose without finding cause
Rounds · GI / Hepatology
RFHE 2010 · EASL HE Guidelines 2018
CardiologyRate/RhythmCommon
Atrial Fibrillation
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) |
Common Triggers & Causes
- Hypertension -most common modifiable risk factor
- Heart failure -AF and HF exacerbate each other
- Valvular disease -especially mitral stenosis/regurgitation
- Thyrotoxicosis -always check TSH in new AF
- Alcohol -"holiday heart" (binge drinking → AF)
- 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
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).
- Troponin -RVR can cause demand ischemia
- CBC -anemia worsens tachycardia and symptoms
- Mg²⁺ -replete aggressively (target ≥ 2.0). Low Mg = refractory RVR.
- Consider PE workup if new AF + dyspnea + tachycardia + hypoxia
Pearl: Always replete K⁺ > 4.0 and Mg²⁺ > 2.0 in AF with RVR. Hypomagnesemia is the most common missed cause of refractory rate control.
💊 Rate Control
| Drug | Dose | Best For | Avoid In |
|---|---|---|---|
| Metoprolol succinate 1ST LINE | 25–200 mg PO daily | First-line. HTN, HFrEF (evidence-based BB), ACS | Decompensated HF, severe bradycardia, asthma |
| Diltiazem (Cardizem) ER 1ST LINE | 120–360 mg PO daily | Preserved EF. Fast symptom relief. COPD-safe. | HFrEF (EF < 40%), WPW, concurrent BB |
| Verapamil (Calan) | 120–480 mg PO daily | Alternative CCB if diltiazem intolerant | Same as diltiazem. More constipation. |
| Digoxin (Lanoxin) | 0.125–0.25 mg PO daily | Add-on if BB/CCB insufficient. HFrEF. Sedentary patients. | Renal failure (adjust dose), hypokalemia (toxicity risk). Target level 0.5–0.9 ng/mL. |
| Amiodarone (Cordarone) HFrEF ONLY | 200 mg PO daily | HFrEF with refractory rate. Also provides rhythm control. | Long-term toxicities: thyroid, liver, lung, cornea, skin. Monitor TFTs/LFTs/PFTs q6 months. |
⚡ Rhythm Control
When to Consider Rhythm Control
- Symptomatic despite adequate rate control
- Young patients with first episode
- 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. |
| Dofetilide INPATIENT ONLY | HFrEF, structural disease. Inpatient initiation required. | 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.
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.
| Letter | Risk Factor | Points |
|---|---|---|
| H | Hypertension (uncontrolled, SBP > 160) | 1 |
| A | Abnormal renal/liver function (1 pt each) | 1–2 |
| S | Stroke (prior) | 1 |
| B | Bleeding (history or predisposition) | 1 |
| L | Labile INR (if on warfarin, TTR < 60%) | 1 |
| E | Elderly (age > 65) | 1 |
| D | Drugs (antiplatelets, NSAIDs) or alcohol (≥ 8 drinks/week) (1 pt each) | 1–2 |
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 -no renal dose adjustment unless Cr > 1.5 AND age > 80 AND wt < 60kg).
Step 3 -Assess for Cause:
TSH (hyperthyroidism?), TTE (structural heart disease, valvular?), BMP (electrolytes), troponin (ACS trigger?).
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.
- BMP -electrolytes (K⁺, Mg²⁺), Cr (for DOAC dosing)
- 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 BID PREFERRED | 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
Rate Control
BB or non-DHP CCB (diltiazem). Target HR < 110 at rest [RACE II]. Digoxin add-on if refractory. Avoid CCB in HFrEF.
Rhythm Control
Consider if symptomatic, new-onset (< 1 year), younger patient. Cardioversion + flecainide/amiodarone or catheter ablation.
Anticoagulation
CHA₂DS₂-VASc ≥ 2 (men) or ≥ 3 (women) → DOAC (apixaban, rivaroxaban). Warfarin only if mechanical valve or severe MS.
Stroke Risk
CHA₂DS₂-VASc: CHF(1), HTN(1), Age≥75(2), DM(1), Stroke/TIA(2), Vasc disease(1), Age 65-74(1), Sex female(1).
Acute RVR
Stable: IV diltiazem 20 mg → drip. Unstable: synchronized cardioversion 120-200J biphasic. Replete K⁺ and Mg²⁺.
Don't Miss
Check TSH (hyperthyroid), echo (structural), sleep study (OSA -#1 modifiable risk factor for AF recurrence).
📄 One Pager
Atrial Fibrillation -Quick Reference Card
Print this page (Ctrl/Cmd + P) for a complete reference card.
ATRIAL FIBRILLATION -AT A GLANCE
📋 Diagnose: Irregularly irregular, no P waves, narrow QRS
🧪 Workup: ECG, TSH, BMP (K⁺/Mg²⁺), TTE, troponin if ACS concern
⚡ Acute RVR: Unstable → cardiovert. Stable → diltiazem 20 mg IV → drip
💊 Rate control: Metoprolol (HFrEF) or Diltiazem (preserved EF). Target HR < 110.
⚡ Rhythm control: Flecainide (no structural disease) or Amiodarone (HFrEF)
💉 Anticoag: CHA₂DS₂-VASc ≥ 2M/3F → Apixaban 5 mg BID (preferred DOAC)
📈 Monitor: HR, rhythm, K⁺/Mg²⁺, renal function, QTc if on AAD
📣 Present: See Rounds tab
🧪 Workup: ECG, TSH, BMP (K⁺/Mg²⁺), TTE, troponin if ACS concern
⚡ Acute RVR: Unstable → cardiovert. Stable → diltiazem 20 mg IV → drip
💊 Rate control: Metoprolol (HFrEF) or Diltiazem (preserved EF). Target HR < 110.
⚡ Rhythm control: Flecainide (no structural disease) or Amiodarone (HFrEF)
💉 Anticoag: CHA₂DS₂-VASc ≥ 2M/3F → Apixaban 5 mg BID (preferred DOAC)
📈 Monitor: HR, rhythm, K⁺/Mg²⁺, renal function, QTc if on AAD
📣 Present: See Rounds tab
📋 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.
Key findings: BP 142/88, K⁺ 3.4, Mg 1.2, TSH normal, troponin negative. CHA₂DS₂-VASc = 5.
Management:
- Replete Mg > 2.0 and K⁺ > 4.0 first — most commonly missed cause of refractory RVR
- Diltiazem 20 mg IV bolus x2, then drip 10 mg/hr (CCB safe in preserved EF)
- Transition to diltiazem ER 180 mg daily
- Apixaban 5 mg BID (CHA₂DS₂-VASc ≥ 2) ARISTOTLE, 2011
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
- Hemodynamically unstable — synchronized cardioversion 120-200J biphasic
- 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."
Monitoring -Atrial Fibrillation
| Parameter | Frequency | Target / Action |
|---|---|---|
| Heart rate | Continuous telemetry inpatient; daily resting HR outpatient | Resting HR < 110 bpm (lenient) RACE II, 2010. Stricter < 80 if symptomatic. |
| Rhythm | Telemetry inpatient; ambulatory monitor (Holter/Zio) outpatient | Assess AF burden, recurrence after cardioversion, breakthrough episodes on AAD |
| Electrolytes (K⁺, Mg²⁺) | Daily inpatient; q3–6 months outpatient | K⁺ > 4.0, Mg²⁺ > 2.0 -low levels promote AF and reduce AAD efficacy |
| Renal function | At DOAC initiation, then q6–12 months | Adjust DOAC dose per CrCl. Apixaban: 2.5 mg dose if ≥ 2 of (age ≥ 80, wt ≤ 60, Cr ≥ 1.5). |
| TSH | At diagnosis; annually if on amiodarone | Amiodarone causes both hyper- and hypothyroidism (iodine load) |
| LFTs, PFTs, TFTs | q6 months if on amiodarone | Monitor for hepatotoxicity, pulmonary fibrosis, thyroid dysfunction |
| QTc | Baseline + 3 days inpatient if starting dofetilide/sotalol | Hold if QTc > 500 ms. Dofetilide requires inpatient initiation. |
📄 One Pager
Cardiology · One Pager
Atrial Fibrillation
Rate control (BB or CCB) + anticoagulation (DOAC if CHA₂DS₂-VASc ≥ 2). Treat triggers: TSH, OSA, alcohol, electrolytes.
🧪 Diagnosis
Irregularly irregular rhythm. No discrete P waves. Can be paroxysmal, persistent, or permanent. Check TSH, echo, electrolytes.
🚨 Acute RVR
IV diltiazem 20 mg → drip 10 mg/hr. Alternative: metoprolol 5 mg IV. Replete K⁺ > 4, Mg > 2. Unstable → cardioversion 120-200J biphasic.
💊 Long-Term
Rate control: BB or CCB (target HR < 110 [RACE II]). Rhythm control if symptomatic/young/new-onset. Anticoag: CHA₂DS₂-VASc ≥ 2M / ≥ 3F → DOAC (apixaban preferred).
💊 Key Drugs
Diltiazem ER180-360 mg daily
Metoprolol XL25-200 mg daily
Apixaban5 mg BID
Amiodarone200 mg daily (rhythm)
⚠️ Pitfalls
- CCB in HFrEF (negative inotrope → worsens HF)
- Not anticoagulating based on CHA₂DS₂-VASc
- Not checking TSH (hyperthyroidism is reversible cause)
- Not screening for OSA (#1 modifiable risk factor for AF recurrence)
RoundsRx · Cardiology
ACC/AHA AF 2023 · RACE II · ARISTOTLE
Interactive Decision Support
Differential Diagnosis Trees
Work through common presentations step-by-step with interactive decision trees. Click through questions to narrow your differential.
🫁
Acute Dyspnea
💔
Chest Pain
🧠
Altered Mental Status
⚠️
Hypotension / Shock
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.
Core Topics
Sepsis & Septic Shock
COPD Exacerbation
ARDS
Airway & Ventilator Management
Cardiogenic Shock
DKA / HHS
Hypertensive Emergency
Hepatic Encephalopathy / ALF
Status Epilepticus
Upper GI Bleed
Post-Cardiac Arrest (ROSC)
Afib with RVR
ADHF
Pulmonary Embolism
Hyperkalemia
Alcohol Withdrawal & DTs
Acute Pancreatitis
Acute Ischemic Stroke
Mesenteric Ischemia
Massive Transfusion Protocol
Brain Death Evaluation
Targeted Temperature Management
Fat Embolism Syndrome
Malignant Hyperthermia
Intubation / RSI
📚 Resources
🌐 Website
Open ↗
POCUS 101 -Cardiac Ultrasound Step-by-Step Guide
https://www.pocus101.com/cardiac-ultrasound-echocardiography-made-easy-step-by-step-guide/
⭐ Featured
🌐 Website
Open ↗
U of T PIE -FOCUS Cardiac POCUS
https://pie.med.utoronto.ca/POCUS/POCUS_content/focus.html
⭐ Featured
📋 Major Guidelines
Clinical Practice Guidelines
6 guidelines
›
Rotation
Cardiology
ACS, arrhythmias, heart failure, valvular disease, and hemodynamic support.
Available Topics
Heart Failure (Chronic / GDMT)
Atrial Fibrillation
STEMI
NSTEMI / Unstable Angina
Arrhythmias
Pericarditis
Aortic Dissection
Infective Endocarditis
Valvular Heart Disease
Syncope
Heart Block & Bradycardia
Myocarditis
Hypertrophic Cardiomyopathy
Cardiac Tamponade
Pulmonary Hypertension
Stable Angina & Chronic CAD
ACS Overview
Aortic Stenosis
Mitral Regurgitation
Cardiogenic Shock
ICU / Cards
Acute Decompensated HF
ICU / Cards
Post-Cardiac Arrest (ROSC)
ICU / Cards
Hypertensive Emergency
ICU / Cards
📚 Resources
📋 Major Guidelines
Clinical Practice Guidelines
12 guidelines
›
GICommon
Cirrhosis & Ascites
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.
MELD-Na Score
- MELD-Na = 3.78 × ln(bilirubin) + 11.2 × ln(INR) + 9.57 × ln(creatinine) + 1.32 × (137 − Na) − 0.025 × MELD + 6.43
- 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.
- Ascites -most common (see Ascites Management tab)
- Variceal hemorrhage -see Upper GI Bleed
- Hepatic encephalopathy -see Hepatic Encephalopathy
- SBP -see Spontaneous Bacterial Peritonitis
- 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. |
| Albumin | Calculate SAAG (serum albumin − ascites albumin). SAAG ≥ 1.1 = portal hypertension (cirrhosis, HF, Budd-Chiari). SAAG < 1.1 = non-portal (malignancy, TB, nephrotic, pancreatitis). |
| Total protein | 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.
- HRS-CKD (Type 2): gradual, stable Cr elevation. Associated with refractory ascites.
- 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, 2024: 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 daily Bañares, 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.
- Varices: nadolol prophylaxis. Bleed: octreotide+ceftriaxone+banding.
- HE: lactulose+rifaximin. Find precipitant.
- SBP: ceftriaxone+albumin. Lifelong prophylaxis.
- HCC: US+AFP q6mo.
- Transplant: refer MELD≥15.
📋 On Rounds
Why give albumin after large volume paracentesis?
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.
Key findings: Tense ascites, shifting dullness. Paracentesis: PMN 680/mm³, SAAG 2.4. WBC 14K.
Management:
- 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.
Key findings: HR 128, BP 82/48, Hgb 6.2, INR 2.1, platelets 68K.
Management:
- Octreotide 50 mcg IV bolus then 50 mcg/hr (reduces portal pressure)
- Ceftriaxone 1g IV daily x7 days (antibiotics reduce mortality in variceal bleed)
- Restrictive transfusion: Hgb 7-8 (overtransfusion increases portal pressure)
- 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, 2024
- 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 -Spontaneous Bacterial Peritonitis
| 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. |
| Vitals | q4h | Fever curve, hemodynamics. Persistent fever > 72h on appropriate antibiotics → reconsider diagnosis. |
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
Decompensation
Ascites, variceal bleed, HE, jaundice, SBP. Marks transition from compensated → decompensated. Median survival drops.
Ascites Rx
Na restriction 2g/day. Spironolactone + furosemide (100:40 ratio). LVP + albumin if tense/refractory. Consider TIPS.
Variceal Bleed
Octreotide drip + ceftriaxone + restrictive transfusion (Hgb 7-8). EGD within 12h for band ligation.
Screening
HCC: US + AFP every 6 months. Varices: EGD at diagnosis, then q1-2 years. Nadolol for secondary prophylaxis.
MELD-Na
Cr + Bilirubin + INR + Na. Determines transplant priority. MELD ≥ 15 → refer for transplant evaluation.
Avoid
NSAIDs (renal failure), aminoglycosides (nephrotoxic), ACEi/ARBs (hypotension), sedatives (worsen HE). Tylenol ≤ 2g/day OK.
💊 Medications
Key Medications -Hepatic Encephalopathy & Acute Liver Failure
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
📄 One Pager
GI / Hepatology · One Pager
Cirrhosis
Screen for HCC (US + AFP q6mo) and varices (EGD). Ascites: Na restrict + spironolactone/furosemide. Avoid NSAIDs, sedatives, aminoglycosides.
🧪 Decompensation Signs
Ascites, variceal bleed, HE, jaundice, SBP. Marks transition to decompensated cirrhosis -median survival drops significantly.
🚨 Ascites Management
Na restriction 2g/day. Spironolactone 100 + furosemide 40 (100:40 ratio). LVP + albumin for tense/refractory. TIPS if refractory (caution: worsens HE).
💊 Screening
HCC: US + AFP every 6 months. Varices: EGD at diagnosis. Band ligation or BB (nadolol) for secondary prophylaxis. MELD-Na ≥ 15 → transplant referral.
💊 Key Drugs
Spironolactone100-400 mg daily
Furosemide40-160 mg daily
Nadolol20-80 mg daily
Lactulose15-30 mL q2-4h (for HE)
⚠️ Pitfalls
- NSAIDs (renal failure in cirrhotics)
- ACEi/ARBs (hypotension)
- Missing HCC screening
- Not doing diagnostic paracentesis for new ascites or clinical change
RoundsRx · GI / Hepatology
AASLD Cirrhosis 2019 · Baveno VII
EMERGENTGI
Spontaneous Bacterial Peritonitis
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.
SBP vs Secondary Peritonitis
| Feature | SBP | Secondary Peritonitis (perforation) |
|---|---|---|
| Organisms | Monomicrobial (single enteric organism -E. coli, Klebsiella, strep) | 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.
SBP Prophylaxis
| Indication | Regimen |
|---|---|
| Prior SBP episode (secondary prophylaxis) | Norfloxacin 400 mg daily (or ciprofloxacin 500 mg daily or TMP-SMX DS daily) -lifelong |
| 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.
Key findings: Paracentesis: PMN 520/mm³ (≥ 250 = SBP). Gram stain: GNR. Ascitic fluid protein 0.8 g/dL. Cr 1.1 (baseline 0.9).
Management:
- 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)
- Broad-spectrum antibiotics: meropenem + vancomycin
- Surgical consultation for possible intervention
- Continue albumin protocol while workup proceeds
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.
Monitoring Parameters -Spontaneous Bacterial Peritonitis
| 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. |
| Vitals | q4h | Fever curve, hemodynamics. Persistent fever > 72h on appropriate antibiotics → reconsider diagnosis. |
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.
🧪 Workup
Diagnostic Evaluation -Spontaneous Bacterial Peritonitis
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
- Ascitic fluid glucose, LDH, protein: If secondary peritonitis suspected (polymicrobial, glucose < 50, LDH > ULN, protein > 1 g/dL → CT abdomen)
- Blood cultures: Before antibiotics -bacteremia common in SBP
- BMP/Cr: Baseline renal function -HRS surveillance
- CBC, LFTs, INR, lactate: Assess severity, liver function, sepsis
💊 Medications
Key Medications -Spontaneous Bacterial Peritonitis
| Drug | Dose | Duration | Notes |
|---|---|---|---|
| Ceftriaxone (Rocephin) 1ST LINE | 2g IV daily | 5 days | 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
Diagnosis
Ascitic fluid PMN ≥ 250/mm³. Do NOT wait for culture. Paracentesis is the test -do it in every cirrhotic with AMS, fever, or pain.
Treatment
Ceftriaxone 2g IV daily × 5 days. Albumin: 1.5 g/kg day 1 + 1 g/kg day 3 (prevents hepatorenal syndrome) SBP Albumin Trial, 1999.
Repeat LP
At 48h: PMN should drop > 25%. If not → broaden abx, consider secondary peritonitis (surgical abdomen).
Prophylaxis
Secondary: norfloxacin or TMP-SMX daily (lifelong). Primary: if ascitic protein < 1.5 + renal/liver dysfunction.
Triggers
GI bleed, UTI, line infection, constipation. Often no identifiable source -spontaneous translocation from gut.
Prognosis
1-year mortality ~30-50% after first SBP episode. Start transplant evaluation immediately.
📄 One Pager
Spontaneous Bacterial Peritonitis -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.
SPONTANEOUS BACTERIAL PERITONITIS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
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)
- Not starting lifelong secondary prophylaxis
- Missing secondary peritonitis (surgical abdomen, multiple organisms)
RoundsRx · GI / Hepatology
AASLD Ascites 2021 · Sort 1999
UrgentGI / ID
Clostridioides difficile (C. diff)
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.
- Recommended algorithm: GDH screen (sensitive) → if positive → toxin EIA (specific). Or: NAAT + toxin EIA together. NAAT-positive + toxin-negative = possible carrier -clinical judgment needed.
Severity Classification (IDSA/SHEA 2021)
| Severity | Criteria |
|---|---|
| Non-severe | WBC ≤ 15,000 AND Cr < 1.5 mg/dL |
| Severe | WBC > 15,000 OR Cr ≥ 1.5 |
| Fulminant | Hypotension, shock, ileus, or megacolon |
💊 Management
Treatment by Severity
| Severity | First Episode | First Recurrence | Second+ Recurrence |
|---|---|---|---|
| Non-severe | 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. |
| Lactate | Elevated lactate = fulminant disease or sepsis. | Lactate > 5 mmol/L = fulminant CDI. Indicates tissue hypoperfusion -consider surgical consult. |
| CT abdomen/pelvis | If concern for fulminant disease, toxic megacolon, or perforation. | Colonic wall thickening, pericolonic stranding, "accordion sign." Colon > 6 cm = megacolon → urgent surgical consult. |
| Abdominal X-ray | Rapid screen for megacolon if CT not immediately available. | Dilated colon, thumbprinting, pneumatosis. Less sensitive than CT. |
💊 Medications
Drug Therapy -C. difficile
| Drug | Dose | Route | Indication | Key Notes |
|---|---|---|---|---|
| Fidaxomicin (Dificid) FIRST-LINE | 200 mg BID × 10 days | PO | First-line for initial and recurrent episodes (non-severe and severe) | Narrow-spectrum -preserves gut flora → lower recurrence (~13% vs ~27% for vancomycin) IDSA/SHEA, 2021. Main limitation: cost (~$3,000). |
| Vancomycin PO | 125 mg QID × 10 days | PO | Alternative first-line. Standard-dose for non-severe and severe. | 500 mg QID for fulminant disease. Not absorbed systemically -acts locally in gut. IV vancomycin does NOT treat C. diff (does not reach colon). |
| Vancomycin pulse-taper | 125 mg QID × 14d → BID × 7d → daily × 7d → q2d × 7d → q3d × 14d | PO | First and subsequent recurrences | 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.
Labs: WBC 12,000 (no bandemia), Cr 0.9 mg/dL (baseline), lactate 1.1 mmol/L. Stool GDH positive, toxin EIA positive.
Classification: Non-severe CDI (WBC ≤ 15K, Cr < 1.5).
Management:
- Discontinue ceftriaxone — switch to narrower-spectrum agent if UTI treatment still needed
- Start fidaxomicin (Dificid) 200 mg PO BID × 10 days PREFERRED — or vancomycin 125 mg PO QID × 10 days IDSA/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.
Classification: Fulminant CDI (hypotension, ileus, megacolon, WBC > 15K, elevated lactate).
Management:
- 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
- Fecal microbiota transplant (FMT) — strongly recommended after ≥ 2 recurrences IDSA/SHEA, 2021. ~85-90% cure rate. FDA-approved products available (fecal microbiota, live-jslm (Rebyota), fecal microbiota spores, live-brpk (Vowst))
- 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. |
| Lactate | q6-12h if severe or fulminant | Lactate > 5 = fulminant disease. Rising lactate = tissue hypoperfusion → ICU, surgical consult. |
| Abdominal exam | At least daily; more frequently if severe/fulminant | Increasing distension, tenderness, guarding, rigidity → CT imaging, surgical consult. Absent bowel sounds + distension = ileus (add rectal vancomycin). |
| Volume status | Each assessment | 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
First-Line
Fidaxomicin 200 BID × 10 days (lower recurrence) IDSA/SHEA, 2021. Alternative: vancomycin PO 125 QID × 10 days.
Fulminant
Vancomycin PO 500 QID + metronidazole 500 IV q8h. Ileus → vancomycin rectal enema. Surgical consult if toxic megacolon.
Infection Control
Contact precautions. Soap and water handwashing (alcohol doesn't kill spores). Dedicated equipment.
Recurrence
First recurrence: fidaxomicin or vancomycin taper/pulse. Multiple: bezlotoxumab. Consider fecal microbiota transplant.
Risk Factors
Recent antibiotics (#1), PPI use, age > 65, hospitalization, immunocompromised, prior C. diff episode.
Surgery Consult
WBC > 30K, lactate > 5, toxic megacolon, organ failure, perforation, refractory to medical therapy.
📄 One Pager
GI / ID · One Pager
C. difficile Infection
Fidaxomicin first-line (lower recurrence). Stop offending antibiotics. Soap and water only (alcohol won't kill spores). Surgery consult if fulminant.
🧪 Diagnosis
Diarrhea (≥ 3 unformed stools/24h) + positive C. diff test (toxin EIA or PCR). Don't test formed stools. Don't test as "test of cure."
🚨 Treatment
Non-severe: fidaxomicin 200 BID × 10 days [IDSA/SHEA 2021] or vancomycin PO 125 QID × 10 days. Fulminant: vanc PO 500 QID + metronidazole 500 IV q8h.
💊 Recurrence
1st recurrence: fidaxomicin or vanc taper/pulse. 2nd+: bezlotoxumab (anti-toxin B antibody). FMT (fecal microbiota transplant) for multiple recurrences.
💊 Key Drugs
Fidaxomicin200 mg BID × 10d
Vancomycin PO125 mg QID × 10d
Metronidazole IV500 mg q8h (fulminant)
Bezlotoxumab10 mg/kg IV × 1 (recurrence prevention)
⚠️ Pitfalls
- Using metronidazole alone (inferior to vancomycin/fidaxomicin)
- Testing for "cure" (don't retest after treatment)
- Not using soap and water (alcohol fails against spores)
- Unnecessary PPI use (risk factor for C. diff)
RoundsRx · GI / ID
IDSA/SHEA C. diff 2021
EmergentGI
Lower GI Bleed
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. | |||
| 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. | |||
| Colitis (ischemic, IBD, infectious) | ~10–15% | Bloody diarrhea + abdominal pain. Ischemic colitis: elderly + hypotension → "watershed" (splenic flexure). IBD: younger, chronic. | |||
| Colorectal cancer/polyps | ~5–10% | 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. | |||
| Test | When | Notes |
|---|---|---|
| CT angiography | Active bleeding (requires > 0.3–0.5 mL/min) | Fast, widely available. Localizes active extravasation. 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.
🧪 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
- LFTs -if upper source suspected (cirrhosis, varices)
Diagnostic Approach
- 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
💊 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) | Weight-based IV | IV | Reversal of rivaroxaban/apixaban. Use for life-threatening bleed only (expensive). |
| 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). (3)
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). (4)
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.
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.
Labs: Hgb 8.0 (baseline 12.0), BUN/Cr ratio 14, INR 1.0, platelets 210K.
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.
Labs: Hgb 6.2, lactate 3.8, BUN/Cr ratio 22 (consider upper source).
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
Most Common
Diverticular bleeding (#1 in elderly, painless), hemorrhoids (#1 overall), angiodysplasia, ischemic colitis, malignancy.
15% Are Upper
Brisk upper GI bleed → hematochezia. Clues: hemodynamic instability, elevated BUN/Cr ratio > 20. EGD before colonoscopy if suspected.
Stable
Colonoscopy within 24h (after prep). Hold anticoag. Transfuse if Hgb < 7.
Unstable
CTA abdomen/pelvis → if active extravasation → IR embolization. If unlocalized → tagged RBC scan or surgical consult.
Ischemic Colitis
Elderly + hypotension + bloody diarrhea + left colon. CT: thumbprinting. Colonoscopy for diagnosis. Supportive care; surgery if gangrenous.
Most Stop
80-85% of LGIB stops spontaneously. Diverticular bleeds recur in ~25%. Definitive treatment if identified: endoscopic, IR, or surgical.
📄 One Pager
GI · One Pager
Lower GI Bleed
15% are actually upper source. Stable → colonoscopy within 24h. Unstable → CTA → IR embolization. Most stop spontaneously. Restrictive transfusion.
🧪 DDx
Diverticular (#1 in elderly, painless, large-volume), hemorrhoids (#1 overall), angiodysplasia, ischemic colitis, malignancy, IBD, post-polypectomy.
🚨 Management
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)
- Not holding anticoagulation
- Over-transfusion (Hgb > 7 threshold for most)
- Not doing colonoscopy within 24h
RoundsRx · GI
ACG LGIB 2023
Rotation
Gastroenterology
GI bleeding, liver disease, pancreatitis, and abdominal emergencies.
Available Topics
Upper GI Bleed
Lower GI Bleed
Hepatic Encephalopathy
Cirrhosis & Ascites
SBP
Acute Pancreatitis
Mesenteric Ischemia
C. difficile
Inflammatory Bowel Disease
Small Bowel Obstruction & Ileus
Cholangitis & Cholecystitis
Acute Alcoholic Hepatitis
Hepatorenal Syndrome
Gallstone Pancreatitis
Autoimmune Hepatitis
PBC / PSC
Acute Liver Failure
Bowel Obstruction
📋 Major Guidelines
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. |
| 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. |
Step 2 -Volume Status (for Hypotonic)
| Volume Status | Urine Na | Causes | Treatment |
|---|---|---|---|
| Hypovolemic (dry mucous membranes, orthostasis, tachycardia, skin tenting) | < 20: extrarenal losses (GI: vomiting, diarrhea; 3rd spacing: burns, pancreatitis) > 20: renal losses (diuretics, adrenal insufficiency, cerebral salt wasting) | GI losses, diuretics, adrenal crisis, burns | 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) | > 40 (inappropriately concentrated urine) | SIADH (#1), hypothyroidism, adrenal insufficiency, psychogenic polydipsia (Uosm < 100), beer potomania, tea-and-toast | Fluid restriction (SIADH). Treat underlying cause. See SIADH topic for details. |
| Hypervolemic (edema, JVD, ascites, anasarca) | < 20: CHF, cirrhosis, nephrotic syndrome (effective hypovolemia → ADH release → water retention) > 20: CKD/ESKD (kidneys can't excrete water) | HF, cirrhosis, nephrotic, CKD | Fluid restriction + treat underlying disease. Diuretics for HF/cirrhosis. Dialysis if ESKD. |
Step 3 -Key Labs to Order
- Serum osmolality (first -classifies the hyponatremia)
- Urine osmolality (Uosm < 100 = appropriate dilution → water overload/polydipsia. Uosm > 100 = kidneys inappropriately concentrating → ADH-mediated)
- 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)
🚨 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. | Fluid restriction (SIADH), NS (hypovolemic), treat underlying cause. Check Na q4–6h. |
| Acute (< 48h, known onset) | 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 sh
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
- Urine Na: 45 mEq/L (> 40 = kidneys wasting Na → SIADH)
- Urine osm: 520 (> 100 = kidneys concentrating inappropriately → SIADH)
- 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.
| Test | Rationale | Key Values / Interpretation |
|---|---|---|
| Serum osmolality | First step -classifies the hyponatremia. | < 275 = hypotonic (true hyponatremia -proceed to step 2). 275-295 = isotonic (pseudohyponatremia -check lipids, protein). > 295 = hypertonic (hyperglycemia -correct Na: add 1.6 mEq/L per 100 mg/dL glucose above 100). |
| Urine osmolality | Distinguishes ADH-mediated from water overload. | < 100 mOsm/kg = kidneys appropriately diluting (polydipsia, beer potomania, tea-and-toast). > 100 = ADH-mediated (inappropriate concentration → SIADH, hypovolemia, hypervolemia). |
| Urine sodium | 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. | Hypovolemic (orthostasis, dry mucous membranes, tachycardia) → NS. Euvolemic → SIADH workup. Hypervolemic (edema, JVD, ascites) → CHF/cirrhosis/nephrotic. |
| TSH | 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. |
| Fluid restriction | 1-1.5 L/day (all PO and IV fluids combined) | - | SIADH (first-line), hypervolemic hyponatremia (HF, cirrhosis) | 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)
Patient: 48 y/o M, chronic alcohol use, Na⁺ 118. Drinks 12+ beers daily, minimal food intake.
Key findings: Serum osm 248, urine osm 52 (maximally dilute — ADH suppressed), UNa 8. Malnourished.
Management:
- Urine osm 52 = ADH appropriately suppressed — this is NOT SIADH
- Low solute intake → low obligate urine output → cannot excrete enough free water
- 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
Step 1
Serum osm: < 275 = true hypoosmolar hyponatremia. ≥ 275 = pseudohyponatremia (hyperglycemia, mannitol, IVIG).
Volume Status
Hypovolemic (FENa < 1): dehydration, diuretics. Euvolemic (UNa > 40): SIADH, hypothyroid, adrenal insuff. Hypervolemic: CHF, cirrhosis, nephrotic.
SIADH Treatment
Fluid restriction < 1L/day → salt tabs → tolvaptan (inpatient only, check Na q6h). Treat the cause.
Correction Rate
≤ 8 mEq/L per 24h (some say ≤ 6 in high-risk). Overcorrection → ODS (osmotic demyelination). Devastating and irreversible.
ODS Rescue
If overcorrecting: D5W + DDAVP 2 mcg IV q8h → re-lower sodium to safe rate. Act immediately.
Severe Symptoms
Seizures, AMS → hypertonic saline 3% NaCl 100-150 mL bolus over 10 min. Target 4-6 mEq/L rise acutely to stop seizures.
📄 One Pager
Nephrology · One Pager
Hyponatremia
Check serum osm → volume status → urine studies. Correct ≤ 8 mEq/24h. Overcorrection → ODS (devastating). Severe symptoms → 3% NaCl 100-150 mL bolus.
🧪 Approach
Step 1: Serum osm (< 275 = true). Step 2: Volume status (hypo/eu/hyper). Step 3: UNa + urine osm. Euvolemic + UNa > 40 + concentrated urine = SIADH.
🚨 Acute Severe Symptoms
Seizures or AMS → 3% NaCl 100-150 mL bolus over 10 min (can repeat ×1). Target 4-6 mEq rise to stop seizures. Then slow correction to ≤ 8/24h total.
⚠️ ODS Prevention
Correct ≤ 8 mEq/24h (≤ 6 if high-risk: Na < 105, chronic, alcoholism, malnutrition, liver disease). If overcorrecting: D5W + DDAVP 2 mcg IV q8h immediately.
💊 Key Drugs
3% NaCl100-150 mL bolus (severe)
DDAVP2 mcg IV q8h (ODS rescue)
Tolvaptan15 mg daily (SIADH, inpatient only)
Salt tabs1g TID (chronic SIADH)
⚠️ Pitfalls
- Overcorrection → ODS (irreversible pontine demyelination)
- 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)
RoundsRx · Nephrology
AJM Hyponatremia Review · Verbalis 2013
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) |
| > 7.45 | Alkalemia (alkalosis is the dominant process) |
Step 2 -Identify the Primary Disorder
| If pH < 7.35 (acidemia) | If pH > 7.45 (alkalemia) |
|---|---|
| PCO₂ > 40 → respiratory acidosis (hypoventilation) | PCO₂ < 40 → respiratory alkalosis (hyperventilation) |
| HCO₃ < 22 → metabolic acidosis | HCO₃ > 26 → metabolic alkalosis |
Step 3 -Is Compensation Appropriate?
| Primary Disorder | Expected Compensation |
|---|---|
| Metabolic acidosis | Winter's formula: expected PCO₂ = 1.5 × [HCO₃] + 8 (± 2). If actual PCO₂ ≠ expected → additional respiratory disorder. |
| Metabolic alkalosis | 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.
| AG Elevated (> 12) | AG Normal (non-AG / hyperchloremic) |
|---|---|
| MUDPILES: M ethanol · U remia · D KA · P ropylene glycol · I soniazid/Iron · L actic acidosis · E thylene glycol · S alicylates | HARDUPS: H yperalimentation (TPN) · A ddison's · R TA · D iarrhea · U reteral diversion · P ost-hypocapnia · S aline (NS resuscitation) |
Step 5 -Delta-Delta (if AG elevated)
Delta-delta = ΔAG / ΔHCO₃ = (AG − 12) / (24 − HCO₃)
| Ratio | Interpretation |
|---|---|
| < 1 | 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
| Urine Cl⁻ | Category | Causes | Treatment |
|---|---|---|---|
| < 20 mEq/L | Chloride-responsive (saline-responsive) | Vomiting/NG suction (#1), diuretics (after stopping), post-hypercapnia | 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. |
Renal Tubular Acidosis (RTA)
| Type | Defect | pH | K⁺ | Classic Association |
|---|---|---|---|---|
| Type 1 (Distal) | Can't secrete H⁺ in distal tubule | Urine pH > 5.5 (can't acidify) | ↓ (hypoK) | Sjögren, SLE, nephrocalcinosis, amphotericin B |
| Type 2 (Proximal) | Can't reabsorb HCO₃ in proximal tubule | Urine pH < 5.5 (once threshold exceeded) | ↓ (hypoK) | Fanconi syndrome, multiple myeloma, carbonic anhydrase inhibitors (acetazolamide) |
| Type 4 (Hypoaldo) | ↓ Aldosterone or tubular resistance | Urine pH < 5.5 | ↑ (hyperK) | 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.
🔍 Overview
Overview
Acid-base disorders are among the most common lab abnormalities in hospitalized patients. A systematic 5-step ABG approach prevents missed mixed disorders.
🧪 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.
- Resp acidosis: COPD→BiPAP. Opioid→naloxone. NMD→intubation.
- Met alkalosis: Cl-responsive→NS+KCl. Cl-resistant→treat cause.
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| NaHCO₃ | 50-150 mEq | IV | Only pH < 6.9. Monitor K⁺. BICAR-ICU, Jaber 2018 |
| Fomepizole | 15 mg/kg load | IV | Toxic alcohols |
| Acetazolamide | 250 mg q6-12h | IV/PO | Refractory met alkalosis |
| KCl | 20-40 mEq q2-4h | IV | Must correct K⁺ to fix met alkalosis |
📋 On Rounds
pH 7.28, PCO₂ 24, HCO₃ 11, Na 140, Cl 100, AG 29. Interpret this ABG.
Step 1: pH 7.28 = acidemia. Step 2: HCO₃ 11 (low) = metabolic acidosis (primary). Step 3: Winter's formula: expected PCO₂ = 1.5(11) + 8 = 24.5 ± 2. Actual PCO₂ = 24 → appropriate respiratory compensation. Step 4: AG = 140 − (100 + 11) = 29 (elevated) → AG metabolic acidosis. Think MUDPILES: DKA? Lactic acidosis? Toxic ingestion? Step 5: Delta-delta = (29−12)/(24−11) = 17/13 = ~1.3 → pure AG metabolic acidosis.
Why do you correct the anion gap for albumin?
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.
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.
Key findings: Step 1: acidemia. Step 2: low HCO₃ = metabolic acidosis. Step 3: Winter's: expected pCO₂ = 1.5(12)+8 = 26 ± 2. Actual 30 → pCO₂ HIGHER than expected → concurrent respiratory acidosis (tiring out?). Step 4: corrected AG = (142-98-12) + 2.5(4-2) = 32+5 = 37 → AG metabolic acidosis. Step 5: delta-delta = (37-12)/(24-12) = 25/12 = 2.1 → hidden metabolic alkalosis (from vomiting? contraction?).
Management:
- 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?
- Address respiratory alkalosis: treat pain/anxiety (may be driving hyperventilation), optimize bronchodilators
- 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
5-Step ABG
1) pH (acid vs alkalemia) → 2) Primary disorder (respiratory vs metabolic) → 3) Compensation adequate? → 4) AG (corrected for albumin) → 5) Delta-delta.
Winter's Formula
Expected pCO₂ = 1.5 × HCO₃ + 8 ± 2. If actual pCO₂ higher → concurrent respiratory acidosis. Lower → respiratory alkalosis.
AG Correction
Corrected AG = AG + 2.5 × (4.0 − albumin). For each 1 g/dL albumin below 4, add 2.5. Hypoalbuminemia hides AG acidosis.
Delta-Delta
ΔAG / ΔHCO₃: Ratio > 2 = hidden metabolic alkalosis. Ratio < 1 = hidden non-AG metabolic acidosis.
MUDPILES
M ethanol · U remia · D KA · P ropylene glycol · I NH/Iron · L actic acidosis · E thylene glycol · S alicylates
Non-AG Causes
HARDUP: Hyperalimentation, Acetazolamide, RTA, Diarrhea, Ureteral diversion, Pancreatic fistula. Also: NS resuscitation.
📄 One Pager
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)
- Treating number without finding cause
- Bicarb for DKA (except pH < 6.9)
- Missing mixed acid-base disorder
RoundsRx · Nephrology / Critical Care
Seifter, NEJM 2014 · Berend, NEJM 2018
EmergentNephrology
Dialysis Indications
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 | Less efficient for small molecules |
| Best for | Outpatient ESKD, emergent dialysis (fast K⁺ removal), toxin removal | 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.
🧪 Workup
Workup
- BMP -K⁺, BUN, Cr, bicarb
- ABG -acidosis severity
- CXR -pulmonary edema
- ECG -hyperK changes
- Tox levels if ingestion
- Access assessment
🚨 Management
Management
- AEIOU: Acidosis pH<7.1, Electrolytes (K⁺ refractory), Ingestion, Overload, Uremia
- HD: stable patients, 3-4h sessions
- CRRT: hemodynamically unstable ICU
- 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?
Intermittent HD: 3-4h sessions, high solute clearance, significant fluid shifts. Use for: stable patients, urgent indications (hyperK, toxic ingestions -high clearance needed fast), outpatient maintenance. CRRT (continuous renal replacement therapy): runs 24/7, slower gentle fluid/solute removal.
Clinical Examples
📋 Case 1 — Emergent Dialysis for Hyperkalemia
Patient: 58M with ESKD on MWF HD (missed 2 sessions). K⁺ 7.2, peaked T waves → widened QRS on ECG. Cr 14.2, BUN 128. Bilateral crackles, JVD.
Key findings: Life-threatening hyperkalemia with ECG changes + volume overload from missed dialysis. AEIOU indications met: Electrolytes (refractory K⁺) + Overload (pulmonary edema).
Management:
- 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. |
| Weight (dry weight target) | Pre/post each HD session | Fluid removal goal = pre-HD weight minus dry weight. Reassess dry weight monthly -clinical exam (edema, JVP, BP) guides adjustment. |
| Access assessment (AV fistula) | Every HD session | 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
Emergent Indications
AEIOU: Acidosis (pH < 7.1), Electrolytes (refractory K⁺ > 6.5), Ingestion (toxic alcohols), Overload (pulmonary edema), Uremia (pericarditis, encephalopathy, bleeding).
HD vs CRRT
HD: 3-4h sessions, stable patients, high clearance. CRRT: continuous, hemodynamically unstable ICU patients, cerebral edema risk.
Access
AV fistula (best long-term, 3-6 months to mature) > AV graft (2-4 weeks) > tunneled catheter (immediate but highest infection risk).
IDH Prevention
Slow UF rate, cool dialysate (35.5°C), midodrine pre-session, hold antihypertensives on dialysis days, extend session time.
Peritoneal Dialysis
Home-based, daily. Good for: independent patients, residual renal function preservation. Risk: peritonitis (cloudy effluate → culture + empiric abx).
Complications
Dialysis disequilibrium (cerebral edema with first session), air embolism, catheter infection, steal syndrome (fistula).
📄 One Pager
Nephrology · One Pager
Dialysis -HD & CRRT
AEIOU for emergent dialysis. HD for stable patients. CRRT for hemodynamically unstable ICU patients. Access: fistula > graft > catheter.
🧪 Emergent Indications -AEIOU
Acidosis (pH < 7.1, refractory). Electrolytes (hyperK refractory). Ingestion (toxic alcohols, salicylates). Overload (pulmonary edema refractory to diuretics). Uremia (pericarditis, encephalopathy, bleeding).
🚨 HD vs CRRT
HD: 3-4h sessions, high clearance, stable patients, outpatient. CRRT: continuous 24/7, gentle fluid removal, hemodynamically unstable ICU patients, cerebral edema risk.
💊 Access
AV fistula (best -refer at eGFR ~20, needs 3-6 months to mature). AV graft (2-4 weeks). Tunneled catheter (immediate, highest infection risk). Peritoneal catheter (home dialysis).
💊 Key Drugs
Calcium gluconateHyperkalemia bridge to HD
HeparinAnticoag for HD circuit
CitrateRegional anticoag for CRRT
EPOAnemia management on HD
⚠️ Pitfalls
- Late fistula referral (needs months to mature)
- IDH from aggressive UF rate (slow down, cool dialysate)
- Dialysis disequilibrium in first session (cerebral edema)
- Not adjusting medications for HD clearance
RoundsRx · Nephrology
KDIGO AKI 2012 · KDOQI Vascular Access 2019
Rotation
Nephrology
AKI, electrolyte disorders, acid-base physiology, and renal replacement therapy.
Available Topics
Acute Kidney Injury
Chronic Kidney Disease
Hyperkalemia
Hyponatremia
Acid-Base Disorders
Acid-Base (Comprehensive)
Dialysis Indications
Metabolic Alkalosis
Nephrotic vs Nephritic Syndrome
Renal Tubular Acidosis
Contrast-Induced Nephropathy
Rhabdomyolysis
Hypernatremia
Renal Transplant Medicine
📋 Major Guidelines
EMERGENTID
Meningitis & Encephalitis
Bacterial meningitis has ~20% mortality even with treatment and doubles with every hour of antibiotic delay. 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 | > 250 mg/dL | 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 | Vancomycin + ceftriaxone + ampicillin (Listeria coverage) |
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.
Imaging: CT head: temporal lobe hypodensity. MRI shows temporal lobe involvement (more sensitive than CT).
LP: Lymphocytic pleocytosis (WBC 120, 95% lymphs), elevated protein, normal glucose, RBCs present.
Diagnosis: HSV encephalitis until proven otherwise.
Treatment:
- IV acyclovir 10 mg/kg q8h — START IMMEDIATELY, do not wait for PCR results.
- HSV PCR is the confirmatory test (sensitivity 98%) but takes 24-48h.
- Every hour of delay in acyclovir increases mortality and neurological damage.
- Duration: 14-21 days IV acyclovir.
If PCR negative but high clinical suspicion: Repeat PCR at 3-5 days (can be false negative early).
Key lesson: Temporal lobe findings + fever + behavioral changes + seizures = acyclovir NOW. Treat first, confirm later. HSV encephalitis is fatal without treatment.
📋 Case 3 — Meningitis in Immunocompromised Patient
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).
Diagnosis: Cryptococcal meningitis.
Treatment:
- Induction: Amphotericin B liposomal 3-4 mg/kg/day + flucytosine 25 mg/kg QID × 2 weeks.
- 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. |
| Acyclovir | 10 mg/kg IV q8h | Add if HSV encephalitis suspected (temporal lobe findings, behavioral changes, seizures) | 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 > 200, 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
Empiric Abx
Vancomycin + ceftriaxone + ampicillin (if > 50, immunocompromised, or pregnant -Listeria coverage). Start within 30 min.
Dexamethasone
10 mg IV q6h × 4 days. Give before or with first antibiotic dose. Reduces mortality in S. pneumoniae European Dexamethasone Meningitis Trial, 2002.
CT Before LP?
Only if: immunocompromised, CNS disease, new seizure, papilledema, focal deficit, altered consciousness. Don't delay abx for CT.
CSF Findings
Bacterial: PMN > 1000, protein > 200, glucose < 40. Viral: lymphocytes, protein 50-100, glucose normal. TB/fungal: lymphocytes, very high protein, low glucose.
Duration
S. pneumoniae: 10-14 days. N. meningitidis: 5-7 days. Listeria: 21 days. HSV encephalitis (acyclovir): 14-21 days.
Chemoprophylaxis
N. meningitidis contacts: rifampin 600 BID × 2 days OR ciprofloxacin 500 × 1 OR ceftriaxone 250 IM × 1.
📄 One Pager
Meningitis & Encephalitis -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.
MENINGITIS & ENCEPHALITIS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
IDCommon
UTI & Pyelonephritis
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 | 7–14 days |
| Pyelonephritis | Upper UTI: fever, flank pain, CVA tenderness ± lower urinary symptoms | 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). |
| Pyelonephritis -outpatient | Ciprofloxacin (Cipro) 500 mg BID × 7 days or levofloxacin (Levaquin) 750 mg daily × 5 days | 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. Assess if catheter is still needed -remove ASAP. |
🔄 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)
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.
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.
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.
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.
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 Evaluation -Clostridioides difficile (C. diff)
Workup checklist for Clostridioides difficile (C. diff): History and physical → targeted labs → imaging as indicated → specialist consultation if needed. Always correlate clinically.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications, relevant PMH
- Physical exam: Focused exam relevant to clostridioides difficile (c. diff) presentation
- Labs: CBC, BMP, relevant disease-specific labs (see Overview tab for specifics)
- Imaging: As clinically indicated based on presentation
- Special studies: Consider disease-specific diagnostics (see Overview tab)
💊 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) | Ceftriaxone FIRST-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
Uncomplicated Cystitis
Nitrofurantoin 100 BID × 5 days (first-line). TMP-SMX × 3 days (if susceptible). Avoid fluoroquinolones (FDA black box).
Pyelonephritis
Ceftriaxone 1g IV daily (inpatient) or ciprofloxacin 500 BID × 7 days (outpatient, if susceptible). Blood cultures + urine culture.
ASB -Don't Treat
Asymptomatic bacteriuria: treat ONLY in pregnancy or pre-urologic surgery. Not in elderly, catheterized, diabetic, or nursing home patients.
Complicated UTI
Male, pregnant, structural abnormality, catheterized, immunocompromised, recent instrumentation → broader coverage, longer course (10-14 days).
Catheter-Associated
Remove or replace catheter + antibiotics. Duration: 7 days (10-14 if delayed response). Don't treat pyuria alone in catheterized patients.
Recurrent UTI
≥ 3/year or ≥ 2 in 6 months. Options: post-coital prophylaxis, continuous low-dose abx, vaginal estrogen (postmenopausal).
📄 One Pager
Clostridioides difficile (C. diff) -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.
CLOSTRIDIOIDES DIFFICILE (C. DIFF) -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
ID · One Pager
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)
- Treating ASB in elderly/catheterized patients
- Nitrofurantoin if CrCl < 30 (ineffective)
- Not culturing urine in pyelonephritis
RoundsRx · ID
IDSA UTI 2011 · AUA/CUA/SUFU 2019
IDChronic
HIV -Inpatient Essentials
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.
🔍 Opportunistic Infections by CD4 Count
| CD4 Count | Opportunistic Infection | Prophylaxis | Treatment |
|---|---|---|---|
| < 500 | Kaposi sarcoma (HHV-8), oral hairy leukoplakia (EBV), candidal vaginitis | ART | ART ± chemo for KS |
| < 200 | PCP (Pneumocystis jirovecii pneumonia) -bilateral GGOs, exertional desaturation, elevated LDH | TMP-SMX DS daily (or dapsone, atovaquone) | TMP-SMX 15–20 mg/kg/day (TMP component) × 21 days. If PaO₂ < 70 or A-a gradient > 35 → add prednisone (taper over 21 days). |
| < 200 | Toxoplasmosis -ring-enhancing brain lesions (multiple, basal ganglia) | TMP-SMX* (covers both PCP + toxo) *TMP-SMX = Trimethoprim-Sulfamethoxazole (Bactrim) | Pyrimethamine + sulfadiazine + leucovorin × 6 weeks |
| < 150 | Histoplasmosis / Coccidioidomycosis (endemic fungi) | ART + itraconazole in endemic areas | Amphotericin B (severe) → itraconazole maintenance |
| < 100 | Cryptococcal meningitis -headache, AMS, ↑ opening pressure on LP. India ink, CrAg+ | Consider CrAg screening if CD4 < 100 | Amphotericin B + flucytosine × 2 weeks → fluconazole maintenance. Serial LPs for pressure management. |
| < 50 | CMV retinitis (flame hemorrhages on fundoscopy), CMV colitis/esophagitis | ART (no specific prophylaxis) | Ganciclovir or valganciclovir |
| < 50 | MAC (Mycobacterium avium complex) -disseminated: fever, weight loss, diarrhea, pancytopenia, elevated alk phos | 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). 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). |
IRIS (Immune Reconstitution Inflammatory Syndrome)
- 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
- Common IRIS pathogens: TB (#1), MAC, cryptococcus, CMV, P
🧪 Workup
Workup
- HIV RNA viral load
- CD4 count + %
- Resistance genotype before ART
- HLA-B*5701 if considering abacavir
- BMP, LFTs, CBC
- HBV/HCV serologies
- RPR, QuantiFERON, toxo IgG
- CXR
🚨 Management
Management
- ART: start ALL patients, within 2wk. Exception: crypto meningitis.
- Preferred: bictegravir/FTC/TAF (1 pill daily)
- OI prophylaxis: CD4<200→TMP-SMX. CD4<50→azithromycin.
- IRIS: continue ART + treat OI + steroids if severe.
💊 Medications
ART Regimens
| Regimen | Dose | Route | Notes |
|---|---|---|---|
| Bictegravir/emtricitabine/TAF (Biktarvy) PREFERRED 1ST LINE | 1 tab daily | PO | INSTI-based single-tablet regimen. High barrier to resistance. Few drug interactions. Well-tolerated. CrCl ≥30. |
| Dolutegravir (Tivicay) + emtricitabine/TAF (Descovy) | 50 mg + 1 tab daily | PO | INSTI-based alternative. Dolutegravir has high barrier to resistance. Avoid with dofetilide, carbamazepine. |
| Dolutegravir/lamivudine (Dovato) | 1 tab daily | PO | Two-drug regimen. Only if VL <500K, no HBV coinfection, and resistance testing available before starting. |
OI Prophylaxis
| Infection | Drug | Indication | Notes |
|---|---|---|---|
| PCP | TMP-SMX DS (Bactrim) 1 tab daily | CD4 <200 or oropharyngeal candidiasis | Also covers toxoplasma prophylaxis. Alternatives: dapsone (check G6PD), atovaquone, aerosolized pentamidine. |
| MAC | Azithromycin (Zithromax) 1200 mg weekly | CD4 <50 | 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?
CD4 < 200: PCP (Pneumocystis jirovecii pneumonia) -bilateral GGO, elevated LDH, hypoxia with exertion. Prophylaxis: TMP-SMX DS daily. Treatment: TMP-SMX high-dose + prednisone if PaO₂ < 70. CD4 < 100: Toxoplasmosis -ring-enhancing brain lesions (multiple, basal ganglia). Prophylaxis: TMP-SMX (same pill covers both PCP and toxo). Treatment: pyrimethamine + sulfadiazine + leucovorin. CD4 < 50: MAC (Mycobacterium avium complex)
What is IRIS and how do you manage it?
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: (1)
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
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
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.
Assessment: Virologic failure — detectable VL despite reported adherence. Must assess true adherence (pharmacy refills, pill counts) and obtain resistance genotype. Genotype reveals K103N mutation — confers high-level NNRTI resistance (efavirenz, nevirapine).
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
Assessment: Virologic failure — detectable VL despite reported adherence. Must assess true adherence (pharmacy refills, pill counts) and obtain resistance genotype. Genotype reveals K103N mutation — confers high-level NNRTI resistance (efavirenz, nevirapine).
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) | Syphilis (RPR), gonorrhea/chlamydia (NAAT, 3-site), hepatitis B/C serology. |
| Cervical/anal cancer screening | Per guidelines | 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 ALL patients regardless of CD4. Start within 2 weeks of diagnosis. Exception: crypto meningitis (wait until CSF sterilized -IRIS risk).
Preferred ART
Bictegravir/emtricitabine/TAF (single pill, once daily). Alternative: dolutegravir-based regimen.
OI Prophylaxis
CD4 < 200: TMP-SMX (PCP + toxo). CD4 < 100: add toxo coverage (same TMP-SMX). CD4 < 50: azithromycin weekly (MAC).
Monitoring
Viral load at 4 weeks (should drop > 1 log), then q3-6 months. Goal: undetectable (< 50 copies/mL). CD4 q3-6 months.
IRIS
Paradoxical worsening 1-12 weeks after starting ART. Continue ART + treat OI + steroids if severe. Don't stop ART.
Resistance
Genotype before starting ART. If virologic failure (detectable VL on ART) → resistance testing → switch regimen.
📄 One Pager
ID · One Pager
HIV
Start ART in ALL patients regardless of CD4. OI prophylaxis by CD4 count. TMP-SMX covers PCP + toxo. Monitor VL + CD4. Watch for IRIS.
🧪 Key CD4 Thresholds
< 200: PCP risk → TMP-SMX. < 100: toxoplasma risk → TMP-SMX covers both. < 50: MAC risk → azithromycin weekly. < 50: CMV risk → monitor.
🚨 ART
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)
- Forgetting pre-ART screening (QuantiFERON, RPR, HBV, genotype)
- Not recognizing IRIS (can mimic OI relapse)
RoundsRx · ID
DHHS ART Guidelines 2023 · OI Guidelines 2020
Rotation
Infectious Disease
Antibiotic stewardship, sepsis, resistant organisms, and opportunistic infections.
Available Topics
Sepsis & Septic Shock
Meningitis & Encephalitis
UTI & Pyelonephritis
HIV Essentials
Endocarditis
C. difficile
Pneumonia
Osteomyelitis
Cellulitis & Skin Infections
Tuberculosis
Fungal Infections
Diabetic Foot Infection
Necrotizing Fasciitis
Herpes Simplex (HSV)
Syphilis
Herpes Zoster (Shingles)
Septic Arthritis
CLABSI & Line Infections
Intra-Abdominal Infections
📋 Major Guidelines
IDCommon
Osteomyelitis
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 | Post-surgical, trauma, diabetic foot ulcers, decubitus ulcers | S. aureus, coagulase-negative staph (hardware). Polymicrobial (diabetic foot -add gram-negatives + anaerobes). |
| Vascular insufficiency | 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.
Empiric Therapy (Before Culture Data)
| Scenario | Empiric Regimen | Rationale |
|---|---|---|
| Native bone, acute | Vancomycin (Vancocin) (MRSA coverage) + Ceftriaxone (Rocephin) 2g IV daily (gram-negatives) | Covers MRSA + gram-negatives while awaiting cultures. Narrow once sensitivities return. |
| Diabetic foot | Vancomycin (Vancocin) + Piperacillin-tazobactam (Zosyn) 3.375g IV q6h | Polymicrobial -need MRSA + gram-negatives + anaerobic coverage. |
| Post-surgical / hardware | Vancomycin (Vancocin) + Cefepime (Maxipime) 2g IV q8h | Covers MRSA + Pseudomonas + skin flora. Hardware infections often need surgical removal. |
| Vertebral | Vancomycin (Vancocin) + Ceftriaxone (Rocephin) | S. aureus is #1. If IVDU, cover Pseudomonas (use cefepime instead of ceftriaxone). |
| Sickle cell disease | Ceftriaxone (Rocephin) 2g IV daily | Salmonella is #1 in SCD (not S. aureus). Ceftriaxone covers Salmonella + S. aureus. |
Surgical Indications
- Chronic osteomyelitis with sequestrum or sinus tracts
- Failed medical therapy (persistent infection after adequate antibiotics)
- Hardware-associated infection -often requires implant removal
- Abscess requiring drainage
- 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. |
| Polymicrobial (diabetic foot) | Vancomycin (Vancocin) + Piperacillin-tazobactam (Zosyn) | Oral step-down: Amoxicillin-clavulanate (Augmentin) 875mg PO BID + TMP-SMX (Bactrim) (if MRSA) | 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)
- Pain management: NSAIDs + acetaminophen; opioids PRN initially; gabapentin for neuropathic component
- 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%).
📋 Case 3 — Prosthetic Joint Infection
Patient: 74F, 2 years post-right TKR. Progressive knee pain and swelling × 6 weeks, low-grade fever. Knee aspirate: WBC 28,000 (80% PMNs), culture growing coagulase-negative Staph (CoNS). CRP 68, ESR 82.
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
Microbiology
S. aureus is #1 overall. Salmonella in SCD. Pseudomonas in IVDU. Polymicrobial in diabetic foot (staph + gram-negatives + anaerobes).
Diagnosis
MRI = imaging gold standard (sens 90–100%). Bone biopsy with culture = diagnostic gold standard. Probe-to-bone test for diabetic foot (PPV ~89%). Plain films take 10–14 days to show changes.
Treatment Duration
6 weeks of targeted antibiotics. Oral step-down is non-inferior to IV (OVIVA 2019). Hold antibiotics for biopsy if patient is stable.
MSSA / MRSA
MSSA: nafcillin or cefazolin → oral cephalexin. MRSA: vancomycin → oral TMP-SMX + rifampin. Never use rifampin monotherapy.
Surgical Indications
Chronic with sequestrum, failed medical therapy, hardware infection (implant removal), abscess drainage, spinal epidural abscess with neuro compromise.
Monitoring
ESR/CRP weekly (CRP normalizes faster). Vancomycin AUC/MIC if applicable. BMP for nephrotoxicity. Repeat MRI only if treatment failure suspected.
Rotation
Pulmonology
Chronic airway diseases, pulmonary function testing, inhaler management, and acute pulmonary emergencies.
Available Topics
COPD
Asthma
Pleural Effusion
Pneumonia
Pulmonary Nodule & Screening
PFT Interpretation
Pneumothorax
Obstructive Sleep Apnea
Interstitial Lung Disease
Hemoptysis
Sarcoidosis
Pulmonary Embolism
ICU / Pulm
ARDS
ICU / Pulm
COPD Exacerbation (Acute)
ICU / Pulm
📋 Major Guidelines
CommonNeurology
Altered Mental Status & Delirium
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).
AMS Workup -"AEIOU TIPS"
| Letter | Cause | Workup |
|---|---|---|
| A | Alcohol (withdrawal or intoxication), acidosis | BAL, urine tox, ABG, CIWA |
| E | Electrolytes (Na⁺, Ca²⁺, glucose, Mg), endocrine (thyroid, adrenal) | BMP, Ca, Mg, PO₄, TSH, cortisol, glucose |
| I | Infection (UTI, pneumonia, meningitis, sepsis) | CBC, UA, CXR, blood cultures, LP if indicated |
| O | Oxygen (hypoxia, hypercarbia, CO poisoning) | ABG, SpO₂, CO level if suspected |
| U | Uremia, hepatic encephalopathy | BUN/Cr, ammonia, LFTs |
| T | Trauma, temperature (hypo/hyperthermia) | Head CT, core temp |
| I | Iatrogenic (medications -#1 modifiable cause) | Med review: benzos, opioids, anticholinergics, steroids, polypharmacy |
| P | Psychiatric (diagnosis of exclusion), post-ictal | Rule out organic causes first. EEG if concern for non-convulsive status |
| S | Stroke, seizure, space-occupying lesion | CT head, MRI, EEG |
🚨 Management
Non-Pharmacologic -FIRST
Non-pharmacologic prevention reduces delirium incidence by 30–40%. This is more effective than any drug.
- Reorient frequently -clock, calendar, whiteboard with date/nurse/doctor name, familiar objects from home
- Sleep hygiene -lights off at night, minimize nighttime vitals/meds/interruptions, cluster care, earplugs, eye mask
- Early mobilization -out of bed, PT/OT, minimize restraints (restraints worsen delirium)
- Sensory aids -glasses, hearing aids (at bedside, not in a drawer)
- Remove lines/catheters ASAP -Foley, central lines, telemetry if not needed
- Medication review -stop/minimize anticholinergics (diphenhydramine, hydroxyzine, oxybutynin), benzos, opioids. Use the Beers List.
- Treat pain -undertreated pain causes delirium too. Use scheduled acetaminophen, avoid PRN opioids only.
- Avoid physical restraints -they worsen agitation and prolong delirium
Pharmacologic -ONLY If Necessary
| Drug | Dose | When | Notes |
|---|---|---|---|
| Haloperidol (Haldol) | 0.5–2 mg IV/IM/PO q4–6h PRN | Agitated delirium threatening safety (pulling lines, aggression) | 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. 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 (except alcohol/benzo withdrawal -the only indication). Diphenhydramine (Benadryl) is NOT a sleep aid -it's an anticholinergic that causes/worsens delirium. Remove it from every patient's med list.
📋 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. (3)
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.
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).
Management:
- Remove precipitants: Stop morphine PCA (switch to scheduled acetaminophen + low-dose oxycodone PRN). Stop diphenhydramine (strong anticholinergic)
- Treat UTI with appropriate antibiotics
- 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)
- Check metabolic causes: BMP (hyponatremia, hypercalcemia, uremia), TSH, B12, blood cultures
- Mobilize aggressively, ensure adequate nutrition, implement HELP protocol Inouye HELP, 1999
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) MENDS, 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
Diagnostic Evaluation -Delirium
Workup checklist for Delirium: History and physical → targeted labs → imaging as indicated → specialist consultation if needed. Always correlate clinically.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications, relevant PMH
- Physical exam: Focused exam relevant to delirium presentation
- Labs: CBC, BMP, relevant disease-specific labs (see Overview tab for specifics)
- Imaging: As clinically indicated based on presentation
- Special studies: Consider disease-specific diagnostics (see Overview tab)
💊 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
- Sensory aids: hearing aids, glasses at bedside -sensory deprivation worsens delirium
- Avoid restraints: increase agitation, worsen delirium, increase fall risk. Use 1:1 sitter instead.
- Review medications: STOP deliriogenic drugs (anticholinergics, benzodiazepines, opioids, diphenhydramine, muscle relaxants)
Pharmacologic (Severe Agitation Only)
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Haloperidol (Haldol) | 0.5-1 mg, repeat q30-60 min PRN | IV/IM | 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
Diagnosis
CAM: (1) Acute onset + fluctuating course, (2) Inattention, (3) Disorganized thinking, (4) Altered consciousness. Need 1+2 + either 3 or 4.
Prevention
HELP protocol: orientation, sleep hygiene, mobility, glasses/hearing aids, hydration, avoid tethers. Reduces delirium by 33-40%.
Med Review
Stop anticholinergics (diphenhydramine, oxybutynin), benzodiazepines, opioids (minimize), meperidine (never use in elderly).
Workup
Infection (UA, CXR, blood cultures), metabolic (BMP, glucose, Ca²⁺, TSH, ammonia), medications, urinary retention (bladder scan), constipation.
Treatment
Treat the cause. Non-pharm first. Antipsychotics (haloperidol 0.5-2 mg) ONLY for safety-threatening agitation. Don't prevent delirium MIND, 2018.
Subtypes
Hyperactive (agitated, pulling lines -easy to diagnose). Hypoactive (quiet, withdrawn -easy to MISS, worse prognosis). Mixed: fluctuates.
📄 One Pager
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: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
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
- Autonomic dysfunction (~70%): labile BP, tachycardia, bradycardia, arrhythmias, urinary retention, ileus
- Neuropathic pain (~60%) -may be the presenting symptom before weakness
- Facial weakness bilateral (facial diplegia) in ~50%. Bulbar weakness → dysphagia, aspiration risk.
Diagnosis
| Test | Findings |
|---|---|
| CSF (LP) | 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.
- Autonomic monitoring -telemetry (bradycardia, heart block possible). Gentle fluid management (labile BP). Avoid β-blockers (can worsen bradycardia episodes).
📋 On Rounds
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).
Key findings: Classic GBS (AIDP): ascending weakness + areflexia + preceding infection. FVC < 20 mL/kg = intubation threshold ("20-30-40 rule": FVC < 20, MIP < -30, MEP < 40). FVC trending down = impending respiratory failure.
Management:
- ICU admission — check FVC q4-6h (the single most important monitoring parameter)
- IVIG 0.4 g/kg/day × 5 days (first-line — equal efficacy to PLEX, easier to administer)
- Intubate when FVC < 20 mL/kg or declining rapidly — do NOT wait for hypoxia or hypercapnia
- DVT prophylaxis (immobilized), pain management (neuropathic pain is severe — gabapentin), autonomic monitoring (dysautonomia: HR/BP lability)
- NO steroids (do not help GBS, may worsen outcome)
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).
Management:
- NCS/EMG: demyelinating pattern (prolonged distal latencies, temporal dispersion, conduction block)
- Prednisone 1 mg/kg daily × 4-8 weeks → slow taper (first-line for CIDP — unlike GBS, steroids work)
- 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."
Key Points to Cover on Rounds
GBS -ascending, symmetric, areflexic weakness. Preceding GI illness (likely Campylobacter). FVC 28 mL/kg (concerning -approaching 20/30/40 rule). NIF −35 cmH₂O. LP: protein 120, WBC 3 (albuminocytologic dissociation). NCS/EMG: demyelinating pattern (AIDP). Treatment: IVIG 0.4 g/kg/day × 5 days started today. FVC trending q6h: 28→26 (declining). ICU admission. Plan: if FVC <20 or declining rapidly → intubate. DVT prophylaxis (heparin SQ). PT/OT. Monitor autonomic dysfunction (HR/BP lability).
Monitoring -Guillain-Barre Syndrome
| Parameter | Frequency | Target / Action |
|---|---|---|
| FVC (forced vital capacity) | q4–6h (the #1 priority) | 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 dysreflexia) | Continuous telemetry | Labile BP, tachycardia/bradycardia, arrhythmias in ~70% of GBS. Avoid beta-blockers (can worsen bradycardia episodes). Gentle fluid management for BP lability. |
| 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. |
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.
- Ocular symptoms (#1 presenting symptom): ptosis, diplopia -often asymmetric
- Generalized MG: proximal limb weakness, bulbar symptoms (dysphagia, dysarthria, nasal voice), respiratory failure
- Anti-AChR antibodies positive in ~85% of generalized MG. Anti-MuSK antibodies in ~5–8% (more bulbar involvement, worse prognosis).
- CT chest for thymoma -present in ~15% of MG patients. Thymectomy recommended for thymoma and for non-thymomatous generalized AChR+ MG age 18–65.
Drugs That Worsen MG -MUST KNOW
These drugs can precipitate myasthenic crisis. Avoid in all MG patients:
| Drug Class | Specific Agents |
|---|---|
| Antibiotics | Aminoglycosides (gentamicin, tobramycin), fluoroquinolones, macrolides (azithromycin -controversial), tetracyclines |
| Cardiac | Beta-blockers, calcium channel blockers, procainamide, quinidine |
| Neuromuscular blockers | Avoid succinylcholine (unpredictable response). Use non-depolarizing agents with caution (increased sensitivity → prolonged paralysis). |
| Other | Magnesium (blocks NMJ -avoid IV Mg unless life-threatening indication), D-penicillamine, checkpoint inhibitors, botulinum toxin, lithium |
Myasthenic Crisis vs Cholinergic Crisis
| Feature | Myasthenic Crisis | Cholinergic Crisis |
|---|---|---|
| Cause | Disease exacerbation (undertreated) | Pyridostigmine overdose |
| Pupils | Normal or dilated | Miosis (constricted) |
| Secretions | Normal | 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
🧪 Workup
Workup
|
💊 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). (5)
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.
📋 Case 3 — MuSK-Positive MG
Patient: 32F with prominent bulbar symptoms: severe dysphagia, dysarthria, facial weakness, tongue atrophy. Minimal limb involvement. AChR antibodies NEGATIVE. MuSK antibodies POSITIVE. Failed pyridostigmine (made worse).
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
Diagnosis
Fatigable weakness (worse with use, better with rest). Ptosis, diplopia, bulbar symptoms. AChR Ab positive (~85%), MuSK Ab in some.
Treatment
Pyridostigmine (symptomatic). Immunosuppression: prednisone → steroid-sparing (azathioprine, mycophenolate, rituximab).
Crisis
FVC < 20 mL/kg → intubate. Hold pyridostigmine. IVIG or PLEX. ICU admission.
Avoid These Meds
Aminoglycosides, fluoroquinolones, beta-blockers, magnesium, telithromycin, D-penicillamine, botulinum toxin. Worsen NMJ transmission.
Thymectomy
Indicated if thymoma (CT chest mandatory). Also improves outcomes in AChR Ab+ MG without thymoma MGTX, 2016.
Cholinergic Crisis
Excess pyridostigmine → SLUDGE symptoms, weakness, miosis. Antidote: atropine. Hold anticholinesterase. Differentiate from myasthenic crisis.
📄 One Pager
Neurology · One Pager
Myasthenia Gravis
Fatigable weakness (worse with use). AChR antibodies. Pyridostigmine for symptoms. IVIG/PLEX for crisis. Avoid aminoglycosides, FQs, BB, Mg. Thymectomy if thymoma.
🧪 Diagnosis
Fluctuating weakness: ptosis, diplopia, bulbar symptoms (dysphagia, dysarthria), proximal limb weakness. AChR Ab positive ~85%. MuSK Ab in some seronegatives. CT chest (thymoma).
🚨 Myasthenic Crisis
FVC < 20 mL/kg → intubate. Hold pyridostigmine (excess secretions). IVIG 0.4 g/kg/day × 5d or PLEX. Identify trigger: infection, surgery, medication change.
⚠️ Dangerous Medications
Aminoglycosides, fluoroquinolones, macrolides, beta-blockers, magnesium IV, D-penicillamine, telithromycin, botulinum toxin. All worsen NMJ transmission.
💊 Key Drugs
Pyridostigmine60 mg q4-6h
PrednisoneStart low, titrate up (can transiently worsen)
Azathioprine2-3 mg/kg/day (steroid-sparing)
IVIG0.4 g/kg × 5d (crisis)
⚠️ Pitfalls
- Aminoglycosides or FQs in MG patient → crisis
- Not checking FVC (crisis can develop rapidly)
- Missing thymoma (CT chest in all new MG)
- Cholinergic crisis from pyridostigmine excess (SLUDGE symptoms)
RoundsRx · Neurology
AAN MG 2016 · MGTX 2016
Rotation
Neurology
Stroke, seizures, altered mental status, and neuromuscular emergencies.
Available Topics
Status Epilepticus
Acute Ischemic Stroke
AMS & Delirium
Guillain-Barré Syndrome
Myasthenic Crisis
Heat Stroke
Intracerebral Hemorrhage
Headache & Migraine
Spinal Cord Compression
NMS vs Serotonin Syndrome
PRES
📋 Major Guidelines
EmergentNeuro
Heat Stroke
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. |
| Exertional | Young, healthy individuals -athletes, military, laborers | Metabolic heat production overwhelms dissipation during intense physical activity | Develops over hours. Skin may still be diaphoretic. Often in hot, humid environments. Can occur even in cool conditions with extreme exertion. |
Heat Stroke vs Heat Exhaustion
| Feature | Heat Exhaustion | Heat Stroke |
|---|---|---|
| Core Temp | < 40°C (104°F) | > 40°C (104°F) |
| Mental Status | Normal or mild confusion | Altered -confusion, delirium, seizures, coma |
| Sweating | Present (profuse) | May be absent (classic) or present (exertional) |
| Organ Damage | Absent | Present -rhabdomyolysis, DIC, liver failure, AKI, ARDS |
| Treatment | Rest, oral rehydration, passive cooling | Aggressive cooling + ICU |
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.
Risk Factors & Medications
- Anticholinergics -impair sweating (diphenhydramine, TCAs, antipsychotics)
- Diuretics -volume depletion impairs sweating
- 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
- Treat seizures -benzodiazepines (lorazepam 2–4 mg IV). Avoid phenytoin (ineffective for hyperthermia-related seizures).
- 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.
- CBC -leukocytosis common. Thrombocytopenia suggests DIC.
- BMP -hyperkalemia (rhabdo, cell lysis), AKI (elevated Cr), hypoglycemia (liver failure).
- 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, (4)
📣 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.
- Urine output -target 1–2 mL/kg/h (especially with rhabdomyolysis). Foley catheter essential.
- CK q6–12h -trend for rhabdomyolysis. Peak 24–72h. Aggressive IVF if CK rising.
- LFTs daily × 3–5 days -hepatic injury peaks at 48–72h. Watch for coagulopathy, hypoglycemia as signs of liver failure.
- Coags q12–24h -DIC panel (PT, PTT, fibrinogen, D-dimer). Fibrinogen < 150 = ominous.
- BMP q6–12h -hyperkalemia (rhabdo), AKI, hypoglycemia (liver failure).
- Neuro checks q1–2h -GCS trending. Persistent AMS after cooling suggests brain injury.
⚡ Summary
Definition
Core temp >40°C + CNS dysfunction (AMS, seizures, coma). The key distinguishing feature from heat exhaustion is altered mental status, not the temperature.
Cooling
Cold water immersion = gold standard (~0.2°C/min). Target <39°C within 30 min. Stop at 39°C to prevent overshoot. Evaporative + ice packs if no tub available.
Do NOT Give
Antipyretics (acetaminophen, NSAIDs) -useless and harmful. Not a prostaglandin-mediated fever. Phenytoin for seizures -use benzos instead.
Complications
Rhabdomyolysis (CK, IVF, bicarb), DIC (coags q12h, fibrinogen), hepatic failure (LFTs peak 48–72h), AKI, ARDS, cerebral edema.
Classic vs Exertional
Classic: elderly, medications, heat wave, develops over days, skin dry. Exertional: young, exercise, develops over hours, may still be diaphoretic.
Monitoring
Core temp (rectal/esophageal), CK q6–12h, LFTs daily × 3–5d, coags q12–24h, UOP 1–2 mL/kg/h, neuro checks q1–2h.
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. | CTPA (or D-dimer if low pretest). See PE. |
| Tension pneumothorax | Acute pleuritic pain + dyspnea. Absent breath sounds, JVD, tracheal deviation, hypotension. | 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. |
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. |
| Cardiac (non-ACS) | Pericarditis, myocarditis, aortic stenosis | Pericarditis: positional (worse supine, better leaning forward), friction rub, diffuse ST elevation. |
| Psychiatric (~10%) | Panic attack, anxiety | Diagnosis of exclusion. Young, hyperventilation, perioral/extremity tingling, sense of doom. Still need ECG + troponin. |
🧪 Workup
Standard Chest Pain Workup
| Test | When | What It Rules Out |
|---|---|---|
| ECG WITHIN 10 MIN | EVERY chest pain. No exceptions. | STEMI, arrhythmia, pericarditis, PE (S1Q3T3, RV strain), Brugada, WPW |
| Troponin | All chest pain concerning for ACS | Myocardial injury. Serial troponins at 0 and 3h (high-sensitivity). 0 and 6h (conventional). |
| CXR | All admitted chest pain | Pneumothorax, pneumonia, widened mediastinum (dissection), pleural effusion, rib fractures |
| D-dimer | Low-intermediate pretest probability for PE | 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.
🚨 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
📋 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?
The deadly 5: (1) ACS (STEMI/NSTEMI) -ECG + troponin, (2) Aortic dissection -tearing pain, BP differential, widened mediastinum → CTA, (3) Pulmonary embolism -pleuritic, tachycardia, risk factors → Wells + D-dimer or CTPA, (4) Tension pneumothorax -absent breath sounds, tracheal deviation, hypotension → needle decompression BEFORE imaging, (5)
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. 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.
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.
Management:
- ASA 325 mg chew STAT + heparin drip (60 u/kg bolus, 12 u/kg/hr)
- 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.
Management:
- NSAIDs (ibuprofen 600 mg TID) + colchicine 0.5 mg BID x 3 months
- 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
- Diagnosis: musculoskeletal chest pain (costochondritis)
- Outpatient follow-up with PCP, NSAIDs PRN
- Return precautions: recurrent pressure-type pain, exertional symptoms, syncope
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.
💊 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
HEART Score
H(istory) E(CG) A(ge) R(isk factors) T(roponin). 0-3: low risk, safe discharge. 4-6: moderate, observe. 7-10: high risk, admit + cath.
Must Rule Out
ACS, PE, aortic dissection, tamponade, tension PTX, esophageal rupture (Boerhaave). The 6 deadly causes of chest pain.
ECG Clues
ST elevation = STEMI. ST depression = ischemia. Diffuse ST + PR depression = pericarditis. S1Q3T3 + right heart strain = PE.
Troponin
Serial at 0 and 3h (high-sensitivity). Rising pattern = acute MI. Chronically mildly elevated = CKD, HF, PE (not necessarily ACS).
Low Risk Discharge
HEART 0-3 + 2 negative troponins (0 + 3h) + no ECG changes → one of safest discharge criteria in EM.
Atypical Presentations
Women, elderly, diabetics: may present with dyspnea, nausea, fatigue, jaw/back pain without classic substernal pressure. Low threshold for workup.
📄 One Pager
Chest Pain / ACS Workup -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.
CHEST PAIN / ACS WORKUP -AT A GLANCE
📋 Rule out 5 deadly causes: ACS, dissection, PE, tension PTX, Boerhaave
🧪 ECG within 10 min. Serial troponins 0h/3h (hs-troponin 0h/1h)
⚡ ASA 325 chew STAT. NTG 0.4mg SL q5min x3. Heparin if high suspicion.
💊 Beta-blocker if HR/BP allow. High-intensity statin for all ACS.
📈 HEART score: 0–3 = safe discharge. 7–10 = admit + cath.
📣 Continuous telemetry. Serial ECGs with recurrent symptoms.
🧪 ECG within 10 min. Serial troponins 0h/3h (hs-troponin 0h/1h)
⚡ ASA 325 chew STAT. NTG 0.4mg SL q5min x3. Heparin if high suspicion.
💊 Beta-blocker if HR/BP allow. High-intensity statin for all ACS.
📈 HEART score: 0–3 = safe discharge. 7–10 = admit + cath.
📣 Continuous telemetry. Serial ECGs with recurrent symptoms.
📄 One Pager
Emergency / Cardiology · One Pager
Chest Pain Evaluation
HEART score drives disposition. 0-3 = safe discharge. 7-10 = admit + cath. Rule out the 6 deadly causes. Serial troponin at 0 + 3h.
🧪 6 Deadly Causes
ACS (STEMI/NSTEMI), PE, aortic dissection, cardiac tamponade, tension pneumothorax, esophageal rupture (Boerhaave). Every chest pain patient needs these considered.
🚨 HEART Score
History (0-2) + ECG (0-2) + Age (0-2) + Risk factors (0-2) + Troponin (0-2). 0-3: low risk (1.6% MACE) → discharge. 4-6: moderate → observe. 7-10: high → admit + cath.
💊 Workup
ECG (immediate). Troponin 0 + 3h (high-sensitivity). CXR. Consider: D-dimer (PE), CTA (dissection/PE), echo (tamponade, WMA). HEART 0-3 + 2 neg troponins = safe discharge.
💊 Key Drugs
ASA325 mg if ACS suspected
Nitroglycerin0.4 mg SL q5min × 3
HeparinIf ACS confirmed
MorphineCautious (may reduce P2Y12 absorption)
⚠️ Pitfalls
- Anchoring on "musculoskeletal" without ruling out ACS
- Missing posterior STEMI or Wellens pattern on ECG
- Not considering dissection (tearing pain, BP differential)
- Troponin at 0h only (need serial)
RoundsRx · Emergency / Cardiology
ACC/AHA Chest Pain 2021 · HEART Score Validation
EMERGENTEM
Anaphylaxis
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, 2004 WAO, 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." | ||
| 3. IV access + fluids | NS bolus | 1–2 L rapid bolus (20 mL/kg peds) | Anaphylaxis causes massive vasodilation + capillary leak → distributive shock. Aggressive fluids needed. |
| 4. Adjuncts | 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)
- Trigger identification -detailed timeline of exposures (food, drugs, insect stings, latex, exercise)
- 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.
Key findings: Skin + respiratory + hypotension after allergen. HR 128, SpO2 91%, stridor developing.
Management:
- 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.
📋 Case 3 — Biphasic Anaphylaxis
Patient: 25F with peanut allergy. Accidental exposure 6h ago. Initial reaction treated with EpiPen. Resolved. Now: recurrent urticaria, throat tightness, wheezing.
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
Diagnosis
Rapid onset (min to hours) + skin/mucosal involvement + respiratory compromise or hypotension. 10-20% have NO skin findings.
First-Line
Epinephrine 0.5 mg IM anterolateral thigh. Repeat q5-15 min if needed. NO substitute -epi is the ONLY first-line treatment.
Adjuncts
H1 blocker (diphenhydramine 50 mg IV), H2 blocker (famotidine 20 mg IV), steroids (methylprednisolone 125 mg IV), NS bolus for hypotension.
Biphasic
Occurs in ~5% of cases, 1-72h after initial reaction. Observe 4-6h minimum (12-24h if severe). Steroids may help prevent.
Discharge
EpiPen prescription + teach auto-injector. Allergist referral. Anaphylaxis action plan. Medical alert bracelet. Avoid identified trigger.
Common Triggers
Foods (#1 in children: peanuts, tree nuts, shellfish). Medications (#1 in adults: antibiotics, NSAIDs). Hymenoptera stings. Latex.
EMERGENTEM
Toxicology & Overdose
The toxidromes guide your initial management before the specific agent is identified. Know the antidotes cold -they save lives. ABCs first, then identify the toxidrome, then specific antidote + supportive care.
🔍 Toxidromes
| Toxidrome | Vital Signs | Pupils | Other Findings | Common Agents |
|---|---|---|---|---|
| Sympathomimetic | ↑ HR, ↑ BP, ↑ Temp | Mydriasis | Diaphoresis, agitation, seizures, tremor | Cocaine, amphetamines, PCP, MDMA |
| Anticholinergic | ↑ HR, ↑ Temp | Mydriasis | "Hot as a hare, dry as a bone, red as a beet, mad as a hatter, blind as a bat." Urinary retention, ileus, DRY skin | Diphenhydramine, atropine, TCAs, jimsonweed |
| Cholinergic | ↓ HR (or ↑), ↓ BP | Miosis | SLUDGE: Salivation, Lacrimation, Urination, Diarrhea, GI cramping, Emesis. Bronchospasm, fasciculations. | Organophosphates, nerve agents, physostigmine OD |
| Opioid | ↓ HR, ↓ BP, ↓ RR | Miosis ("pinpoint") | Respiratory depression (#1 cause of death), CNS depression, hypothermia | Heroin, fentanyl, morphine, methadone, oxycodone |
| Sedative-hypnotic | ↓ HR, ↓ BP, ↓ RR | Normal or miosis | CNS depression, slurred speech, ataxia, respiratory depression | Benzodiazepines, barbiturates, GHB, ethanol |
| Serotonin syndrome | ↑ HR, ↑ BP, ↑↑ Temp | Mydriasis | Clonus (especially lower extremity), hyperreflexia, tremor, agitation, diarrhea. Key: clonus distinguishes from NMS | SSRIs + MAOIs, SSRIs + tramadol, SSRIs + linezolid |
Sympathomimetic vs anticholinergic -both cause tachycardia + mydriasis + hyperthermia. Key difference: sympathomimetic = DIAPHORESIS (sweating). Anticholinergic = DRY skin.
💊 Key Antidotes
| Poison | Antidote | Dose | Key Pearls |
|---|---|---|---|
| Acetaminophen | N-acetylcysteine (NAC) | IV: 150 mg/kg → 50 mg/kg over 4h → 100 mg/kg over 16h. PO: 140 mg/kg → 70 mg/kg q4h × 17 doses. | Check 4-hour level and plot on Rumack-Matthew nomogram. Above the treatment line → give NAC. If > 8h since ingestion or any doubt → start NAC empirically. NAC is most effective within 8h but beneficial up to 24h+. |
| Opioids | Naloxone (Narcan) | 0.04–0.4 mg IV (start low, titrate to respiratory effort). Repeat q2–3 min. IM/IN: 0.4–2 mg if no IV. | Goal: restore respiratory drive, NOT full consciousness. High-dose naloxone in opioid-dependent patients → acute withdrawal (vomiting → aspiration, agitation, arrhythmia). Fentanyl may need higher doses (2–10 mg). Half-life of naloxone (30–90 min) < most opioids → patient can re-sedate. Observe 4–6h or start drip. |
| Benzodiazepines | Flumazenil (Romazicon) | 0.2 mg IV q1 min (max 3 mg) | RARELY used. Can precipitate seizures in chronic benzo users or TCA co-ingestion. Generally contraindicated in unknown overdose. Supportive care is usually sufficient. |
| TCA (tricyclic antidepressant) | Sodium bicarbonate | 1–2 mEq/kg IV bolus → drip to maintain pH 7.45–7.55 | Hallmarks of TCA toxicity: QRS > 100 ms, R wave in aVR > 3 mm, seizures, hypotension. Bicarb widens the therapeutic window by increasing protein binding of the drug. Also: intralipid 20% for refractory cardiotoxicity. |
| Beta-blocker | Glucagon | 3–10 mg IV bolus → 3–5 mg/hr infusion | Bypasses blocked β-receptors. Also: high-dose insulin (1 unit/kg bolus → 0.5–1 unit/kg/hr) for refractory cases -"hyperinsulinemia-euglycemia therapy" (HIET) -improves cardiac output. Give with D50 + K⁺ monitoring. |
| Calcium channel blocker | Calcium + High-dose insulin | Calcium chloride 1–2g IV. Insulin: same HIET protocol as BB OD. | HIET is the primary treatment for severe CCB OD. Calcium provides temporary ionotropic support. IV lipid emulsion for refractory. Vasopressors (NE) as bridge. |
| Methanol / ethylene glycol | Fomepizole (Antizol) | 15 mg/kg IV loading → 10 mg/kg q12h | Inhibits alcohol dehydrogenase → blocks conversion to toxic metabolites (formate in methanol → blindness; oxalate in EG → AKI). Brent, 2001 Also: hemodialysis if severe (pH < 7.1, renal failure, visual symptoms, serum level > 50). Ethanol IV drip is alternative if fomepizole unavailable (target BAL 100). EXTRIP Guidelines, Lavergne 2012-2020 |
| Organophosphate | Atropine + Pralidoxime (2-PAM) | Atropine 2 mg IV q5 min (titrate to secretion control). 2-PAM 1–2g IV over 15 min. | Atropine controls muscarinic symptoms (secretions). 2-PAM reactivates AChE if given early (< 24–48h before "aging"). No upper limit on atropine dose in organophosphate poisoning -may need 10–100+ mg. |
| Warfarin / rodenticide | Vitamin K + 4F-PCC | Vitamin K 10 mg IV (slow). 4F-PCC for life-threatening bleed. | 4F-PCC reverses INR within minutes. Vitamin K takes 6–24h to work (hepatic synthesis of clotting factors). Give both if actively bleeding. |
| Digoxin | Digoxin-specific antibody fragments (DigiFab) | Empiric: 10–20 vials if acute OD. Calculated: # vials = (level × weight) / 100. | Indications: hemodynamic instability, K⁺ > 5, symptomatic bradycardia/heart block, dig level > 10 (acute) or > 6 (chronic). Avoid calcium in dig toxicity |
🧪 Workup
Workup
- Fingerstick glucose -ALWAYS
- ECG -QRS, QTc
- APAP + salicylate -ALWAYS
- Ethanol
- BMP + AG
- Osmolality -osmol gap
- VBG/ABG
- Specific levels if suspected
🚨 Management
Management
- Stabilize: ABCs, glucose, monitor
- Decontamination: charcoal <1-2h
- Antidotes: NAC (APAP), naloxone (opioid), fomepizole (toxic alcohol) Rumack-Matthew Nomogram, 1975, atropine+2-PAM (organophosphate), bicarb (TCA)
- Enhanced elimination: dialysis, alkalinization
- Poison control: 1-800-222-1222 EVERY case
📋 On Rounds
How do you distinguish serotonin syndrome from neuroleptic malignant syndrome?
Both cause hyperthermia + AMS + autonomic instability, but: Serotonin syndrome: (1) rapid onset (hours) after serotonergic drug, (2) CLONUS (especially lower extremity -most specific sign), (3) hyperreflexia, (4) tremor, (5) diarrhea, (6) mydriasis. NMS: (1) slow onset (days–weeks) after dopamine antagonist (antipsychotic), (2) "lead-pipe" RIGIDITY (no clonus), (3) hyporeflexia, (4) elevated CK (> 1000).
A patient presents with QRS > 100 ms and R wave in aVR on ECG after an overdose. What did they take?
Tricyclic antidepressant (TCA) overdose. TCAs block fast sodium channels in the His-Purkinje system → slowed conduction → QRS widening. QRS > 100 ms predicts seizures. QRS > 160 ms predicts ventricular arrhythmias. The R wave in aVR > 3 mm is another specific marker of sodium channel blockade.
An unknown ingestion patient has pinpoint pupils, respiratory depression, and bradycardia. What toxidrome and what's the antidote?
Opioid toxidrome: CNS depression, respiratory depression, miosis (pinpoint pupils), bradycardia, hypotension, decreased bowel sounds. Antidote: naloxone (Narcan). Start with 0.04-0.4 mg IV (titrate to respiratory effort, NOT consciousness -goal is breathing, not wakefulness). If no response at 2 mg → reconsider diagnosis. Key pitfall: naloxone half-life (30-90 min)
Name the 5 classic toxidromes and one drug example for each.
(1) Sympathomimetic: tachycardia, HTN, hyperthermia, dilated pupils, diaphoresis, agitation. Drugs: cocaine, methamphetamine, MDMA. (2) Anticholinergic: "mad as a hatter, blind as a bat, dry as a bone, red as a beet, hot as a hare." Tachycardia, mydriasis, dry skin/mouth, urinary retention, hyperthermia, AMS. Drugs: diphenhydramine, TCAs, jimsonweed. (3)
Clinical Examples
📋 Case 1 — Acetaminophen Overdose
Patient: 22F brought to ED 6h after intentional ingestion of ~30g acetaminophen (60 tablets). Nausea, RUQ discomfort. AST 82, ALT 68 (rising). APAP level at 4h: 280 mcg/mL. INR 1.1.
Key findings: Acute single ingestion > 150 mg/kg (or > 7.5g). 4h APAP level plots ABOVE the Rumack-Matthew treatment line (150 mcg/mL at 4h). Stage I (0-24h): nausea, vomiting, transaminases may be normal early. Liver failure develops at 72-96h if untreated.
Management:
- N-acetylcysteine (NAC): 150 mg/kg IV over 1h → 50 mg/kg over 4h → 100 mg/kg over 16h (21h IV protocol)
- NAC is nearly 100% effective if given within 8h of ingestion — efficacy drops sharply after 8h
- Activated charcoal 1 g/kg PO if within 1-2h of ingestion (not useful at 6h)
- Monitor: AST/ALT q12h, INR, Cr, lactate. Rising INR = liver synthetic failure = bad sign
- Psychiatry consult (intentional ingestion) + social work. 1:1 sitter
Teaching point: APAP is the #1 cause of acute liver failure in the US. The Rumack-Matthew nomogram is ONLY valid for single acute ingestions with a known time. For chronic/repeated ingestions or unknown timing, treat with NAC empirically if APAP level is detectable or transaminases are elevated.
📋 Case 2 — TCA Overdose with Wide QRS
Patient: 35M found unresponsive with empty amitriptyline bottle. GCS 8, HR 128, BP 85/50, temp 39.1°C. Dilated pupils, dry skin. ECG: QRS 148 ms, rightward axis, terminal R wave in aVR > 3 mm. Seizure in ED.
Key findings: TCA toxicity triad: altered mental status + seizures + wide QRS. Anticholinergic toxidrome (tachycardia, mydriasis, dry skin, hyperthermia). QRS > 100 ms = sodium channel blockade → risk of VT/VF. Terminal R in aVR = specific for TCA toxicity.
Management:
- Sodium bicarbonate 1-2 mEq/kg IV bolus → drip 150 mEq in 1L D5W at 200 mL/hr (narrows QRS by overcoming sodium channel blockade + alkalinizing plasma reduces free drug)
- Target: QRS < 100 ms and serum pH 7.50-7.55
- Benzodiazepines for seizures (lorazepam 4 mg IV) — do NOT use phenytoin (worsens sodium channel blockade)
- Intubate for GCS ≤ 8. IVF bolus for hypotension → norepinephrine if refractory
- No activated charcoal if AMS (aspiration risk). No gastric lavage
Teaching point: Sodium bicarbonate is the antidote for TCA-induced wide QRS — it works by two mechanisms: (1) sodium load overcomes the sodium channel blockade, and (2) alkalinization increases protein binding of TCA. Watch the QRS on continuous telemetry — it's your real-time guide to therapy.
📋 Case 3 — Toxic Alcohol Ingestion (Ethylene Glycol)
Patient: 48M found confused in parking lot with empty antifreeze container. pH 7.12, HCO₃ 8, AG 32. Osmolal gap 42. Cr 2.8. Calcium oxalate crystals in urine. Ethanol level 0.
Key findings: Ethylene glycol poisoning: severe AG metabolic acidosis + elevated osmolal gap + calcium oxalate crystals (pathognomonic). Metabolized by alcohol dehydrogenase → glycolic acid (causes acidosis) → oxalic acid (precipitates as calcium oxalate in kidneys → AKI).
Management:
- Fomepizole 15 mg/kg IV loading dose → 10 mg/kg q12h (alcohol dehydrogenase inhibitor — blocks toxic metabolite formation)
- Emergent hemodialysis: pH < 7.25, Cr rising, or end-organ damage (removes both parent compound and toxic metabolites)
- Sodium bicarbonate for severe acidosis (pH < 7.1)
- Thiamine 100 mg + pyridoxine 100 mg IV (cofactors that shunt metabolism toward non-toxic pathways)
- Monitor: serial ABGs, osmolal gap (should close with treatment), Cr, calcium
Teaching point: The osmolal gap closes as the parent alcohol is metabolized — a normal osmolal gap does NOT rule out toxic alcohol poisoning if the patient presents late (all converted to metabolites). Late presentations have a closed osmolal gap but a severely elevated anion gap.
📣 Sample Presentation
One-Liner
"Mr. Garcia is a 22-year-old brought in by friends after intentional ingestion of unknown quantity of acetaminophen ~6 hours ago. He is asymptomatic. APAP level 220 mcg/mL at 6 hours (above the Rumack-Matthew treatment line)."
Key Points to Cover on Rounds
Acetaminophen toxicity -APAP 220 at 6h (above treatment line). AST/ALT currently normal (may take 24-48h to rise). NAC protocol started: 150 mg/kg IV loading dose over 1h, then 50 mg/kg over 4h, then 100 mg/kg over 16h. INR 1.0, Cr 0.8 (no end-organ damage yet). Activated charcoal not given (>4h since ingestion). Poison control contacted. Psychiatry consulted for intentional ingestion. Plan: serial LFTs, APAP levels, INR q6h. Continue NAC until APAP undetectable + ALT trending down + INR normal. 1:1 sitter for safety.
Monitoring
- Continuous telemetry
- Serial ECGs
- Repeat APAP at 4h
- LFTs q12h if APAP
- ABG trend
- UOP
⚡ Summary
Summary
5 Toxidromes
Sympathomimetic (cocaine/meth), anticholinergic (diphenhydramine/TCA), cholinergic/SLUDGE (organophosphates), opioid (fentanyl), sedative-hypnotic (benzos).
Universal Workup
Fingerstick glucose, ECG (QRS/QTc), APAP level, salicylate level, ethanol level, BMP, lactate. Coingestants are common.
APAP Toxicity
Rumack-Matthew nomogram. NAC: 150 mg/kg load → 50 mg/kg/4h → 100 mg/kg/16h. Start if above treatment line. Don't wait for level if massive ingestion.
Antidotes
Naloxone (opioids), flumazenil (benzos -cautious), NAC (APAP), fomepizole (methanol/ethylene glycol), atropine + pralidoxime (organophosphates).
Decontamination
Activated charcoal if < 1-2h post-ingestion and intact airway. Whole bowel irrigation for sustained-release, iron, lithium, body-packing.
Call Poison Control
1-800-222-1222. Always. Even for cases that seem straightforward. They have expertise and track outcomes.
📄 One Pager
Emergency / Toxicology · One Pager
Toxicology
5 toxidromes. APAP level + salicylate + ECG on every overdose. Poison control: 1-800-222-1222. NAC for acetaminophen. Naloxone for opioids. Treat the patient, not the poison.
🧪 5 Toxidromes
Sympathomimetic (cocaine): mydriasis, HTN, diaphoresis. Anticholinergic (diphenhydramine): mydriasis, dry, hot. Cholinergic (organophosphate): SLUDGE, miosis. Opioid: miosis, RD, CNS depression. Sedative-hypnotic: CNS depression, normal pupils.
🚨 Universal Workup
Fingerstick glucose, ECG (QRS/QTc), APAP level, salicylate level, ethanol, BMP, lactate, VBG. Call Poison Control on EVERY case: 1-800-222-1222.
💊 Key Antidotes
NAC (APAP). Naloxone (opioids). Fomepizole (methanol/ethylene glycol). Atropine + pralidoxime (organophosphates). Flumazenil (benzos -cautious). Digibind (digoxin). Lipid emulsion (local anesthetic toxicity).
💊 Key Drugs
NAC150 mg/kg → 50 mg/kg/4h → 100 mg/kg/16h
Naloxone0.04-2 mg IV titrate to breathing
Fomepizole15 mg/kg IV load
Activated charcoal1g/kg PO (< 1-2h, intact airway)
⚠️ Pitfalls
- Not checking APAP/ASA levels (coingestants common)
- Under-dosing naloxone for fentanyl (may need 10-20 mg)
- Flumazenil in chronic benzo users (seizures)
- Missing serotonin syndrome (clonus, hyperthermia, agitation)
RoundsRx · Emergency / Toxicology
AACT/ACMT Guidelines · Poison Control
Rotation
Emergency Medicine
Resuscitation, rapid assessment, undifferentiated presentations, and critical procedures.
Available Topics
Post-Cardiac Arrest (ROSC)
Hypertensive Emergency
DKA / HHS
Alcohol Withdrawal
Chest Pain Workup
Anaphylaxis
Toxicology & Overdose
Trauma Primary & Secondary Survey
Acute Abdomen
Burns Management
Hypothermia & Drowning
Toxicology (Comprehensive)
Intubation / RSI
Acute Limb Ischemia
Necrotizing Fasciitis
Status Epilepticus
ICU / Neuro
Pulmonary Embolism
ICU / Pulm
📋 Major Guidelines
Rotation
Night Float
Everything you need for cross-cover. Common pages, escalation algorithms, when to call your senior, and how to survive the night.
🚨 Common Cross-Cover Scenarios
📋 Cross-Cover Algorithms
Fever, Hypotension, Desat, AMS, Chest Pain, Low UOP
🔴 Code Blue & Rapid Response
ACLS, H's & T's, code drugs
💊 Electrolyte Replacement
K⁺, Mg²⁺, PO₄, Ca²⁺ protocols
💉 Opioid & Steroid Conversions
Equianalgesic tables, steroid equivalency
💧 IV Fluid Guide
Which fluid for which scenario
🧪 Lab Interpretation
CBC, BMP, LFTs, coags
💊 Antibiotic Guide
Empiric coverage by infection site
🔢 Calculators
GCS, MELD, CrCl, Winter's
📞 Most Common Night Float Pages
Hyperkalemia
K⁺ > 6.0 with ECG changes
Sepsis / Septic Shock
New fever + hemodynamic instability
Acute HF / Flash Pulmonary Edema
New dyspnea, desaturation
Afib with RVR
HR > 140, palpitations
DKA / HHS
Glucose > 500, AG > 20
Alcohol Withdrawal
Tremor, CIWA > 15, seizure risk
GI Bleed
Hematemesis, melena, Hgb drop
Pulmonary Embolism
New dyspnea, tachycardia, pleuritic pain
Acute Stroke
New focal deficit, tPA window
Inpatient Fall
CT head if on anticoag
Delirium / Agitation
CAM, non-pharm first
Chest Pain
ECG, troponin, 5 deadly causes
🌙 Night Float Survival Guide
When to Call Your Senior
- 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 | Check QTc. Avoid in Parkinson's/Lewy body. Try reorientation, family, lights first. |
| Fever | Acetaminophen 650 mg + blood cultures × 2 | 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.
📋 Major Guidelines
CommonWards
Anemia Workup
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 |
| 80–100 | Normocytic | Anemia of chronic disease (#1), acute blood loss, CKD (↓ EPO), mixed deficiency (iron + B12), hemolysis (check hemolysis labs), bone marrow failure (aplastic, MDS, infiltration) | Reticulocyte count (↑ = destruction/loss, ↓ = underproduction), BMP (CKD), hemolysis labs (LDH, haptoglobin, indirect bili, smear) |
| > 100 | Macrocytic | B12 deficiency (neurologic symptoms -subacute combined degeneration), folate deficiency, alcohol/liver disease, hypothyroidism, MDS, medications (methotrexate, hydroxyurea, azathioprine, AZT), reticulocytosis (reticulocytes are large → MCV ↑) | 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 | ↓ (< 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.
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
- Hemolytic: autoimmune→steroids±rituximab. TTP→PLEX. Mechanical→treat cause.
- CKD: iron first, then ESA (Hgb 10-11)
- Transfuse: Hgb<7 most, <8 ACS TRISS, Holst 2014 TITRe2, Murphy 2015
📋 On Rounds
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: (1)
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).
Key findings: Hgb 7.6, MCV 65, ferritin 4, TIBC 520, TfSat 4%, reticulocyte index 0.5%. Smear: microcytic hypochromic cells, pencil cells.
Management:
- IV iron (ferric carboxymaltose 750 mg x 2) due to severity
- Gynecology referral for menorrhagia management
- GI workup deferred given clear gynecologic source and young age
Teaching point: Pica (pagophagia) is specific for iron deficiency. In premenopausal women, menorrhagia is the most common cause. IRON-MIDE, 2020
📋 Case 2 — Normocytic Anemia with Hemolysis
Patient: 42-year-old woman with SLE presents with jaundice, dark urine, and worsening fatigue. Splenomegaly on exam.
Key findings: Hgb 6.2, MCV 102 (elevated from reticulocytosis), reticulocyte count 12%, LDH 680, haptoglobin undetectable, indirect bilirubin 4.8, DAT positive (IgG + C3).
Management:
- 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. |
⚡ Summary
Summary
MCV Approach
Microcytic (< 80): iron deficiency, thalassemia, chronic disease, sideroblastic. Normocytic (80-100): chronic disease, CKD, hemolysis, bleeding. Macrocytic (> 100): B12/folate, MDS, liver disease, hypothyroid, drugs.
Iron Deficiency
Ferritin < 30 (or < 100 in CKD/inflammation), low Tsat. Find the source: GI (colonoscopy), menstrual, malabsorption. IV iron for severe/refractory.
Hemolysis Workup
LDH ↑, haptoglobin ↓, indirect bilirubin ↑, reticulocyte ↑. Coombs test: positive = autoimmune. Negative = mechanical (TTP, DIC, prosthetic valve).
Transfusion Threshold
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).
📄 One Pager
Anemia Workup -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.
ANEMIA WORKUP -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
Hematology · One Pager
Anemia
MCV-based approach: micro (iron), normo (chronic disease, hemolysis, bleeding), macro (B12/folate). Reticulocyte count = production vs destruction. Transfuse Hgb < 7.
🧪 MCV Approach
Microcytic (< 80): iron deficiency (#1), thalassemia, chronic disease, sideroblastic. Normocytic (80-100): chronic disease, CKD, hemolysis, acute bleeding. Macrocytic (> 100): B12/folate, MDS, liver disease, hypothyroid, drugs.
🚨 Iron Deficiency
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.
💊 Hemolysis Workup
LDH ↑, haptoglobin ↓, indirect bili ↑, reticulocyte ↑. Coombs positive = autoimmune (warm vs cold). Coombs negative = mechanical (TTP, DIC, valve), PNH, G6PD, sickle cell.
💊 Key Drugs
Ferric carboxymaltose750 mg IV × 2 doses
Cyanocobalamin1000 mcg IM daily × 7d
Folic acid1 mg PO daily
EPO50-300 U/kg 3×/wk (CKD)
⚠️ Pitfalls
- Transfusing above Hgb 7 threshold without indication
- Not checking reticulocyte count (production vs destruction)
- Missing B12 deficiency (can cause pancytopenia mimicking leukemia)
- Iron infusion without finding the source of loss
RoundsRx · Hematology
ASH Anemia Guidelines · TRICC · TRISS
CommonWards / ID
Cellulitis & Skin Infections
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 sufficient IDSA, 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). 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%). 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.
- BMP -baseline Cr (for antibiotic dosing), glucose (uncontrolled DM worsens outcomes and increases recurrence risk)
- Blood cultures -only if systemic signs/sepsis (fever > 38.5°C, tachycardia, hypotension, immunocompromised). NOT routine for simple cellulitis -yield is < 2% IDSA, 2014
- 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 | Covers Group A strep. No MRSA coverage needed. Elevate limb, mark borders, follow-up in 48h. |
| Moderate (inpatient) Systemic signs, rapid spread, failed PO | Cefazolin (Ancef) 2g IV q8h | Transition to PO at 48–72h | Admit if: fever, tachycardia, WBC > 15K, rapidly spreading, immunocompromised, facial/periorbital/hand cellulitis. |
| Purulent / Abscess Fluctuance, drainable collection | 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. 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.
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.
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
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
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
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.
Monitoring Parameters -Cellulitis & Skin Infections
| Parameter | Frequency | Target / Action |
|---|---|---|
| Demarcation line progression | 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).
💊 Medications
Antibiotic Selection -Cellulitis & Skin Infections
| Scenario | Drug (Brand) | Dose | Notes |
|---|---|---|---|
| Non-purulent cellulitis (outpatient) 1ST LINE | Cephalexin (Keflex) | 500 mg PO QID × 5–7 days | 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. |
| Severe / necrotizing fasciitis EMERGENT | Vancomycin + piperacillin-tazobactam (Zosyn) + clindamycin (Cleocin) | 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
Non-Purulent
Likely strep (Group A). Cephalexin 500 QID × 5-7 days (outpatient) or cefazolin 2g IV q8h (inpatient). No I&D needed.
Purulent/Abscess
Likely MRSA. I&D is primary treatment. TMP-SMX or doxycycline for surrounding cellulitis. Clindamycin alternative.
Mark Borders
Skin marker + date/time at periphery of erythema. Objective assessment of response at 48h. If spreading past lines → broaden or image.
Admit Criteria
Systemic toxicity (fever, tachycardia, WBC > 15K), rapid spread, failed outpatient PO, immunocompromised, facial/periorbital/hand.
IV → PO Switch
Afebrile × 24h, WBC trending down, erythema receding past marked borders (usually 48-72h). Transition to oral equivalent.
Nec Fasc Red Flags
Pain out of proportion, rapid spread, crepitus, hemorrhagic bullae, skin necrosis, systemic toxicity. Emergent surgical exploration.
📄 One Pager
Cellulitis & Skin Infections -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.
CELLULITIS & SKIN INFECTIONS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
QualityWards
Falls & Delirium Prevention
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.
🛡️ Prevention Bundle
High-Risk Medications -Review and Stop
| Drug Class | Examples to Stop/Minimize | Safer Alternative |
|---|---|---|
| Benzodiazepines | Lorazepam, midazolam, diazepam | Melatonin 3–5 mg for sleep. Trazodone 25–50 mg. Non-pharmacologic sleep hygiene. |
| Anticholinergics | 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.
Post-Fall Assessment
🧪 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. |
| Neuro exam | GCS, pupil symmetry, focal deficits, gait (if ambulatory) | Document GCS and neuro status. If on anticoag + head strike → CT head STAT + repeat at 24h if on warfarin. |
| Vitals | Orthostatic BP/HR (lying → sitting → standing) | Drop ≥ 20/10 or HR rise ≥ 30 = orthostatic hypotension → volume depletion, meds, autonomic dysfunction |
| ECG | Arrhythmia, heart block, QTc prolongation | New arrhythmia → telemetry. Syncope-related fall → full syncope workup. |
| Labs | BMP (Na, glucose, Ca), CBC (anemia), INR if on warfarin | Correct metabolic causes. Check drug levels if applicable (digoxin, AEDs). |
| Medication review | Benzos, opioids, antihypertensives, anticholinergics, antipsychotics, diuretics | Deprescribe fall-risk meds. Use Beers Criteria AGS, 2023. Taper, don't abruptly stop. |
⚡ Management
Fall Prevention -Inpatient
| Intervention | Details |
|---|---|
| Bed alarm | For high-risk patients (delirium, impaired mobility, prior fall). NOT physical restraints -restraints increase falls and agitation. |
| Non-slip socks + clear pathway | Remove clutter, ensure call bell within reach, bed in lowest position, nightlight on. |
| Medication reconciliation | Reduce/eliminate: benzodiazepines (#1 contributor), opioids, sedating antihistamines (diphenhydramine), antihypertensives causing orthostasis, anticholinergics. |
| Delirium prevention (HELP protocol) | Orientation aids (clock, calendar), minimize nighttime disruptions, early mobilization, hearing aids/glasses at bedside, avoid unnecessary catheters. |
| PT/OT consult | Gait assessment, strength training, assistive device evaluation. Early mobilization reduces deconditioning. |
| Treat underlying cause | Orthostatic hypotension → IVF, adjust meds. Syncope → cardiac workup. Delirium → find precipitant. Neuropathy → B12, glucose control. |
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.
💊 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. |
| Anticholinergics | Diphenhydramine, oxybutynin, cyclobenzaprine | Delirium, sedation, blurred vision, urinary retention | Substitute: cetirizine for allergy, mirabegron for OAB. |
| Opioids | Oxycodone, morphine, tramadol | Sedation, dizziness, impaired coordination | Multimodal pain: acetaminophen, topical NSAIDs, nerve blocks. |
| Antihypertensives | Alpha-blockers (doxazosin), loop diuretics | Orthostatic hypotension, volume depletion | 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). |
📋 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. (4)
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. (5)
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
- Medication review: identify fall-risk medications (benzos, opioids, anticholinergics, alpha-blockers, sleep aids)
- 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.
Post-Fall Monitoring
| Parameter | Frequency | Action |
|---|---|---|
| Neuro checks | q4h × 24h if head strike + anticoag | GCS, pupil reactivity, focal deficits. Decline → repeat CT head STAT. |
| Repeat CT head | 24h post-fall if on warfarin + head strike | 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: apixaban (avoid < 25), rivaroxaban (avoid < 30). Declining renal function → may need to 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.
⚡ Summary
Summary
Immediate
Assess for injury: CT head (if on anticoag or unwitnessed), C-spine if neck pain, hip XR if pain with weight-bearing. Neurovascular exam.
Medications
Beers Criteria review: stop/reduce benzos, anticholinergics, sedative hypnotics, antipsychotics, first-gen antihistamines. Minimize opioids.
Orthostatics
Supine → standing: SBP drop > 20 or DBP drop > 10 = positive. Cause: meds (antihypertensives, diuretics), dehydration, autonomic neuropathy.
Prevention Bundle
PT evaluation, assistive device, bed alarm, non-slip footwear, clear path to bathroom, toileting schedule, adequate lighting, hip protectors.
On Anticoag
CT head NOW + repeat at 24h (delayed intracranial hemorrhage). Consider reversal if significant ICH found. Low threshold for imaging.
Root Causes
Medications (#1 modifiable), orthostatic hypotension, delirium, visual impairment, gait/balance disorder, environmental hazards, polypharmacy.
📄 One Pager
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
🧪 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.
- Post-thrombotic syndrome: 20-50% of DVT patients develop chronic venous insufficiency (pain, swelling, ulcers)
- 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
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.
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%.
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%.
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.
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: Massive PE only: sustained hypotension (SBP < 90 for > 15 min), pulselessness, or persistent bradycardia. Alteplase 100mg IV over 2h is standard. NOT for submassive PE (RV strain + normal BP) -PEITHO trial showed tPA reduced hemodynamic collapse but increased ICH. Submassive = anticoagulation + close monitoring.
A: Massive PE only: sustained hypotension (SBP < 90 for > 15 min), pulselessness, or persistent bradycardia. Alteplase 100mg IV over 2h is standard. NOT for submassive PE (RV strain + normal BP) -PEITHO trial showed tPA reduced hemodynamic collapse but increased ICH. Submassive = 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).
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).
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: Submassive 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: Submassive PE (RV strain + elevated biomarkers, but hemodynamically stable). Start heparin drip. Monitor closely in ICU. tPA NOT indicated unless hemodynamic decompensation. PEITHO, 2014
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: Submassive PE (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.
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).
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.
- Anticoagulation therapeutic? aPTT (heparin drip), anti-Xa (LMWH), INR (warfarin)
- Platelet monitoring: q2-3 days on heparin (days 4-14) for HIT surveillance
- Renal function: CrCl for LMWH/DOAC dosing adjustments
- Bleeding assessment: GI symptoms, hematuria, gum bleeding, hemoptysis, surgical site
- Leg symptoms: Swelling trending? Pain improving? Signs of extension?
- Hemodynamics (PE): HR, BP, SpO2 trending. Any signs of RV failure?
- Transition plan: Bridge to oral anticoagulation. Discharge with follow-up (hematology if unprovoked/recurrent)
🧪 Workup
DVT Diagnosis
| Wells DVT Score | Points |
|---|---|
| Active cancer (treatment within 6 months) | 1 |
| Paralysis/paresis/recent cast of lower extremity | 1 |
| Bedridden > 3 days or major surgery within 12 weeks | 1 |
| Localized tenderness along deep venous system | 1 |
| Entire leg swollen | 1 |
| Calf swelling > 3 cm compared to other leg | 1 |
| Pitting edema (greater in symptomatic leg) | 1 |
| Collateral superficial veins (non-varicose) | 1 |
| Previously documented DVT | 1 |
| Alternative diagnosis as likely or more likely | -2 |
Score ≥ 2: DVT likely → duplex ultrasound. Score < 2: DVT unlikely → D-dimer first (if negative, DVT ruled out).
PE Diagnosis
| Wells PE Score | Points |
|---|---|
| Clinical signs/symptoms of DVT | 3 |
| PE is #1 diagnosis (or equally likely) | 3 |
| Heart rate > 100 | 1.5 |
| 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 massive 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 |
| Submassive | 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 massive 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, 2010 |
| 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.
Thrombolysis for Massive PE
Massive PE (SBP < 90 × 15 min, cardiac arrest, or persistent bradycardia): Alteplase (tPA) 100mg IV over 2 hours (or 50mg bolus in arrest). Give WITH heparin. Absolute contraindications: active internal bleeding, recent (2 months) CVA, intracranial neoplasm. Mortality benefit outweighs bleed risk in massive PE.
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
Prophylaxis
Padua ≥ 4 → enoxaparin 40mg SQ daily. CrCl < 30 → heparin 5000u SQ q8h. Bleeding risk → SCDs only.
DVT Workup
Wells DVT score. ≥ 2 → ultrasound. < 2 → D-dimer first. Negative D-dimer rules out DVT.
PE Workup
PERC (low risk only) → Wells PE. ≤ 4 → D-dimer (age-adjusted). > 4 → CTPA directly. PIOPED II gold standard.
First-Line Treatment
Apixaban 10mg BID × 7d → 5mg BID (non-cancer). LMWH for cancer VTE (avoid DOAC in GI cancers).
Duration
Provoked: 3 months. Unprovoked: ≥ 3 months → extend if low bleed risk. Cancer: indefinite. Recurrent: indefinite.
Pearl
HIT surveillance: platelets q2-3 days on heparin (days 4-14). > 50% drop → 4T score → PF4 antibody. Stop ALL heparin if suspected.
📄 One Pager
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. Massive 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). Massive 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).
CoreWards
Discharge Planning Checklist
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." |
| COPD | Inhaler technique reviewed (observed return demonstration). Action plan. Smoking cessation. Pulmonary rehab referral. Prednisone taper if applicable. |
| Pneumonia | Complete antibiotic course. CXR follow-up in 6–8 weeks (to ensure resolution, rule out underlying mass). Smoking cessation. |
| ACS | DAPT education (do NOT stop without cardiology approval). Cardiac rehab referral. Statin, BB, ACEi. Nitroglycerin SL PRN prescription + instruction. Follow-up within 2 weeks. |
🧪 Workup
Pre-Discharge Checklist
| Domain | Before Discharge |
|---|---|
| Clinical stability | Afebrile ≥ 24h, improving trajectory, tolerating PO, ambulatory (or at baseline), stable vitals off telemetry |
| Pending results | Blood cultures, biopsy, imaging reads, consult recs -assign follow-up responsibility for each. Document who will call patient. |
| Medication reconciliation | Compare admission meds → current → discharge. Mark: NEW / CHANGED / STOPPED. Verify patient can access + afford meds. |
| Follow-up arranged | PCP within 7 days (48–72h if high-risk). Specialist follow-up with date. Labs with specific date and location. |
| Transitions of care | Discharge summary sent to PCP SAME DAY. Include: diagnosis, hospital course, pending results, medication changes, follow-up plan. |
⚡ Management
High-Risk Discharge Situations
| Situation | Risk | Mitigation |
|---|---|---|
| New anticoagulation | Bleeding, missed doses, drug interactions | Teach signs of bleeding, drug-food interactions (warfarin), ensure INR follow-up if warfarin |
| New insulin | Hypoglycemia, dosing errors | Teach-back injection technique, glucose monitoring, hypo treatment. Diabetes educator consult. |
| Heart failure | 30-day readmission (25%) | Daily weights, sodium restriction, diuretic adjustment plan, 48–72h follow-up, call if gain > 3 lbs/2 days |
| COPD exacerbation | Readmission, ongoing steroid needs | Ensure inhaler technique (observed), prednisone taper written, pulmonary rehab referral, quit smoking |
| AMA discharge | Poor outcomes, medicolegal risk | 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
I-PASS Handoff
Illness severity → Patient summary → Action list → Situation awareness → Synthesis by receiver. Reduces errors by 30% I-PASS Study, 2014.
Med Reconciliation
At bedside: review every med (new, changed, stopped). Teach-back: patient explains each med. Ensure meds in hand, not just prescriptions.
Follow-Up
PCP within 7 days for most. Within 48-72h for HF. Specialists as needed. Ensure patient has appointment BEFORE discharge.
Red Flags
Written instructions with specific return precautions: fever, worsening symptoms, new symptoms, unable to take meds, unable to eat/drink.
Readmission Prevention
Phone call within 48h post-discharge. Medication adherence check. Confirm follow-up appointments. Address social barriers (transport, cost).
Transitions of Care
Discharge summary to PCP same day. Include: diagnosis, hospital course, pending results, follow-up needs, medication changes with rationale.
📄 One Pager
SAFE DISCHARGE -AT A GLANCE
💊 Med rec: Compare lists → mark NEW/CHANGED/STOPPED → teach-back → access check
📋 Pending: Assign owner for every pending result
📅 Follow-up: PCP 7d (48–72h if high-risk). Specialist with date. Labs with date + location.
📄 Summary: To PCP same day -diagnosis, course, meds, pending, plan
🚨 Red flags: Specific symptoms to return for (not generic)
📞 Phone call: 24–48h post-discharge to verify meds filled + understanding
📋 Pending: Assign owner for every pending result
📅 Follow-up: PCP 7d (48–72h if high-risk). Specialist with date. Labs with date + location.
📄 Summary: To PCP same day -diagnosis, course, meds, pending, plan
🚨 Red flags: Specific symptoms to return for (not generic)
📞 Phone call: 24–48h post-discharge to verify meds filled + understanding
🔍 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), (3)
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. (3)
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"
- Dietary counseling: 2g sodium restriction, avoid canned foods, read labels (involve family/caregiver)
- 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)
- NEW: ticagrelor 90 mg BID (must take twice daily — missed doses increase stent thrombosis risk)
- 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.
📄 One Pager
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
RoundsRx · Transitions of Care
I-PASS Study, Starmer 2014 · SHM Transitions Toolkit
Rotation
General Wards
The bread and butter of internal medicine. Common inpatient diagnoses, admission workups, discharge planning, and transitions of care.
Available Topics
VTE Prophylaxis & Treatment
Discharge Planning Checklist
Admission Orders & I-PASS
Anemia Workup
Cellulitis & Skin Infections
Falls & Delirium Prevention
VTE Prophylaxis
Delirium
Discharge Planning & Transitions
Perioperative Medicine
Inpatient Diabetes Management
📋 Major Guidelines
EMERGENTHeme/Onc
DIC
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 |
| Fibrinogen | ↓ (< 100 = severe) | Consumed. Most specific for DIC severity. |
| PT/INR, aPTT | ↑ | Clotting factors consumed |
| D-dimer | ↑↑↑ | Massive fibrinolysis |
| Smear | Schistocytes | RBCs sheared through fibrin strands |
Common Triggers
- Sepsis (~35% -most common)
- Trauma / major surgery
- Malignancy -APL, mucin-secreting adenocarcinomas (pancreas, prostate)
- Obstetric -placental abruption, amniotic fluid embolism, HELLP
- Massive transfusion, large aortic aneurysm, envenomation
🚨 Management
#1: Treat the underlying cause. DIC will not resolve until the trigger is removed. JAAM DIC Criteria, Gando 2006
| Component | Replacement | Target |
|---|---|---|
| Fibrinogen | Cryoprecipitate 10 units | > 100–150 mg/dL. Most critical to replace. ISTH DIC Guidelines, Levi 2009 |
| Platelets | Platelet transfusion | > 50K if bleeding; > 10K if not |
| Factors | FFP 15 mL/kg | INR < 1.5 if bleeding |
| RBCs | pRBCs | Hgb > 7 (or > 8 if active bleed) |
💊 Medications
Key Medications -Disseminated Intravascular Coagulation
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.
Key findings: Plt 28K, INR 3.2, fibrinogen 62, D-dimer > 20,000. Peripheral smear: schistocytes. ISTH DIC score 7 (overt DIC). Factor VIII LOW (confirming DIC, not liver disease).
Management:
- 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
- Aggressive blood product support: keep fibrinogen > 150, plt > 50K in APL
- 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)
- Start plasma exchange (PLEX) immediately — untreated TTP mortality > 90%
- 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.
Monitoring Parameters -Disseminated Intravascular Coagulation
| Parameter | Frequency | Target / Action |
|---|---|---|
| CBC (platelets, Hgb) | q6-8h in acute DIC | Platelet trend (rising = improving). Hgb drop = ongoing hemorrhage or hemolysis. Check smear for schistocytes. |
| Fibrinogen | q6-8h in acute DIC | Target >150 mg/dL. Most specific lab for DIC severity. Replete with cryoprecipitate if <100-150. |
| PT/INR, aPTT | q6-8h in acute DIC | Trend toward normalization. Prolonged + bleeding → FFP. Improving PT/fibrinogen = resolving DIC. |
| D-dimer | q6-12h | Massively elevated in DIC. Trending down = resolving. Not specific -use in context of ISTH score. |
| ISTH DIC score | Daily recalculation | ≥5 = overt DIC. Track serial scores -declining score confirms resolution. Components: platelets, D-dimer, PT, fibrinogen. |
| Clinical bleeding assessment | q2-4h | 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
Diagnosis
Thrombocytopenia + prolonged PT/INR + low fibrinogen + elevated D-dimer + schistocytes. ISTH DIC score ≥ 5 = overt DIC.
Key Lab
Fibrinogen is the most specific and actionable. < 100 → cryoprecipitate (10 units). Factor VIII: LOW in DIC, ELEVATED in liver disease (best differentiator).
Treatment
Treat the underlying cause (sepsis, malignancy, obstetric emergency). Transfuse: cryo for fibrinogen < 100, platelets if < 50 + bleeding, FFP for INR + active bleeding.
Do NOT Give
Heparin in acute DIC with active bleeding (controversial -only for DIC with dominant thrombotic features, e.g., purpura fulminans).
Causes
Sepsis (#1), trauma, malignancy (APL, mucin-secreting cancers), obstetric (placental abruption, amniotic fluid embolism, HELLP), transfusion reaction.
Monitor
Fibrinogen, plt, PT/INR, D-dimer q4-6h until stable. Trend is more important than absolute values.
📄 One Pager
Disseminated Intravascular Coagulation (DIC) -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.
DISSEMINATED INTRAVASCULAR COAGULATION (DIC) -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup
Workup
- CBC + smear -thrombocytopenia + schistocytes
- PT/INR, aPTT -prolonged
- Fibrinogen -most specific. Cryo if <100.
- D-dimer -markedly elevated
- Factor VIII -LOW in DIC, HIGH in liver disease
- ISTH DIC score ≥5
EMERGENTHeme/Onc
TTP / HUS
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
TTP vs HUS
| Feature | TTP | Typical HUS | Atypical HUS |
|---|---|---|---|
| Mechanism | ADAMTS13 < 10% → ultra-large vWF → platelet aggregation | Shiga toxin (E. coli O157:H7) | Complement dysregulation |
| Key features | Neuro predominant (confusion, seizures) | Renal failure + bloody diarrhea (children) | Renal failure |
| Coags | NORMAL (PT, aPTT, fibrinogen all normal) | Normal | Normal |
| Treatment | Plasma exchange + steroids + caplacizumab | Supportive (abx CONTRAINDICATED) | Eculizumab (anti-C5) |
| Criterion | 1 Point Each |
|---|---|
| P | Platelet < 30,000 |
| L | 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
Clinical Examples
📋 Case 1 — Classic Acquired TTP
Patient: 34F with confusion, petechiae, fatigue × 3 days. Hgb 7.2, platelets 11K, Cr 1.6, LDH 1800, haptoglobin < 10, indirect bili 4.2. Smear: abundant schistocytes. PLASMIC score 7 (high risk).
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
- Prednisone 1 mg/kg daily (suppress autoantibody production)
- 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).
- ADAMTS13 inhibitor level (Bethesda assay) -quantifies antibody titer. Helps differentiate immune TTP from congenital TTP.
- 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
Suspect When
MAHA (schistocytes) + severe thrombocytopenia + end-organ damage (neuro, renal). Do NOT wait for ADAMTS13 -start treatment.
PLASMIC Score
6-7 = high probability of ADAMTS13 < 10% → start PLEX tonight. Don't delay for confirmatory testing.
Treatment
Triple therapy: (1) PLEX daily until plt > 150 × 2 days, (2) steroids (methylpred 1g IV × 3 days), (3) caplacizumab HERCULES, 2019.
Do NOT Transfuse Plt
Contraindicated -platelets fuel the thrombotic process. Analogy: adding fuel to fire. Transfuse RBCs only if needed.
Differentiate from HUS
TTP: neuro-predominant (confusion, seizures, focal deficits). HUS: renal-predominant (AKI, oliguria). Both have MAHA + thrombocytopenia.
Relapse
ADAMTS13 monitoring after recovery. Relapse risk ~30-50% for autoimmune TTP. Rituximab for relapsing or refractory disease.
📄 One Pager
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)
RoundsRx · Hematology
ASH TTP 2020 · HERCULES 2019
EMERGENTHeme/Onc
Tumor Lysis Syndrome
Massive cell death → release of intracellular contents (K⁺, PO₄, uric acid, nucleic acids). Occurs 12–72h after chemo initiation. Highest risk: high tumor burden + rapidly proliferating cancers (ALL, Burkitt, DLBCL). Kills via hyperkalemia, AKI, and cardiac arrest.
🔍 Overview
Cairo-Bishop Criteria Cairo-Bishop Classification, 2004
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 |
| Calcium | ↓↓ | Bound by elevated phosphate | Seizures, QT prolongation, tetany |
| Uric acid | ↑↑ | Purine breakdown from nucleic acids | Crystal deposition in renal tubules → AKI |
High-Risk Cancers
- Highest risk: ALL (especially B-cell), Burkitt lymphoma, DLBCL (high LDH, bulky disease)
- 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, 2001 CONTRAINDICATED 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
- AKI: IVF,
🧪 Workup
Workup
- K⁺, PO₄, Ca²⁺, uric acid, Cr -the "TLS panel." Check q6-8h starting 12-24h before chemotherapy in high-risk tumors. Cairo-Bishop criteria: lab TLS = ≥ 2 of: K⁺ ≥ 6, PO₄ ≥ 4.5, Ca²⁺ ≤ 7, uric acid ≥ 8 (or 25% change from baseline).
- 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.
Why is rasburicase contraindicated in G6PD deficiency?
Rasburicase is a recombinant urate oxidase that converts uric acid to allantoin (which is easily excreted). The reaction produces hydrogen peroxide (H₂O₂) as a byproduct. Normally, red blood cells neutralize H₂O₂ using glutathione, which requires G6PD to regenerate. In G6PD deficiency, RBCs cannot handle the oxidative stress → massive hemolysis + methemoglobinemia, which can be fatal.
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).
Clinical Examples
📋 Case 1 — TLS Prevention in High-Risk ALL
Patient: 19M newly diagnosed B-ALL, WBC 142K, LDH 2800, uric acid 9.8, Cr 1.4, K⁺ 5.2, PO₄ 5.8. Starting induction chemotherapy tomorrow.
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)
- Insulin 10 U + D50 (shift K⁺), albuterol 20 mg nebulized
- 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)
- Aggressive IVF 200-250 mL/hr targeting UOP > 2 mL/kg/hr
- 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.
- LDH trending -should decline after initial surge. Persistent elevation → ongoing tumor lysis.
- 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
Lab Criteria
Cairo-Bishop: ≥ 2 of: K⁺ > 6, PO₄ > 4.5, uric acid > 8, Ca²⁺ < 7 (or 25% change from baseline). Clinical TLS = lab TLS + organ dysfunction.
Prevention
Aggressive IVF 200-250 mL/hr + allopurinol (prophylaxis only). Rasburicase prophylaxis if high-risk (Burkitt, ALL with high WBC).
Treatment
Rasburicase (converts existing uric acid → allantoin, not allopurinol). Aggressive IVF. Patiromer/Lokelma for K⁺. Dialysis if refractory.
Do NOT
Don't give calcium for hypocalcemia unless symptomatic (increases CaPO₄ precipitation → renal damage). Don't give allopurinol for established TLS.
High-Risk Tumors
Burkitt lymphoma, ALL (high WBC), DLBCL, bulky tumors. Monitor: K⁺, PO₄, Ca²⁺, uric acid, Cr, LDH q6-8h after chemo initiation.
When to Dialyze
Refractory hyperkalemia, refractory hyperphosphatemia, volume overload, severe symptomatic hypocalcemia, worsening AKI despite treatment.
📄 One Pager
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.
🧪 Diagnosis
Cairo-Bishop: ≥ 2 lab abnormalities (K⁺ > 6, PO₄ > 4.5, uric acid > 8, Ca²⁺ < 7) OR 25% change from baseline. Clinical TLS = lab TLS + organ dysfunction.
🚨 Treatment
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
- Rasburicase in G6PD deficiency (hemolysis)
RoundsRx · Oncology / Nephrology
ASCO TLS Guidelines 2023
EmergentHeme/Onc
Sickle Cell
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. | Antibiotics (ceftriaxone + azithromycin -covers atypicals + encapsulated), exchange transfusion if severe (target HbS < 30%), supplemental O₂, bronchodilators, incentive spirometry |
| Stroke | Children: ischemic (large vessel). Adults: hemorrhagic more common. Sudden neuro deficit. | Exchange transfusion emergently (target HbS < 30%). Chronic transfusion program to prevent recurrence. |
| Splenic sequestration | Sudden splenomegaly + hemoglobin drop ≥ 2 from baseline + reticulocytosis. Mostly children (adults with HbSC). | Volume resuscitation + transfusion. Can be fatal within hours. Consider splenectomy after recovery. |
| Aplastic crisis | Parvovirus B19 → transient red cell aplasia. Hgb drops, reticulocyte count near zero. | Supportive. Transfuse if symptomatic anemia. Self-limited (1–2 weeks). |
| Priapism | Painful sustained erection > 4 hours. Urologic emergency. | 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. |
| Neisseria meningitidis | Meningococcemia, meningitis | Fulminant course with purpura fulminans. Requires meningococcal vaccines (MenACWY + MenB). |
| Salmonella species OSTEOMYELITIS | Osteomyelitis -most common cause in SCD | 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. |
| Azithromycin (Zithromax) | 500 mg IV/PO daily | ACS (atypical coverage) | Covers Mycoplasma, Chlamydophila -common ACS triggers. |
| Hydroxyurea DISEASE-MODIFYING | 15–35 mg/kg/day PO | Chronic -all SCD patients | ↑ HbF → ↓ sickling. Reduces crises, ACS, mortality. Teratogenic. Monitor CBC q4–8wk. |
| Penicillin VK | 125 mg BID (age < 3) → 250 mg BID (age 3–5) | Prophylaxis (children) | Prevents pneumococcal sepsis. PROPS, 1986: ↓ sepsis by 84%. |
| Amoxicillin-clavulanate | 875/125 mg PO BID × 5d | Dog/cat bite prophylaxis | Covers Capnocytophaga + Pasteurella. Start immediately -do not wait for signs of infection. |
| Folic acid | 1 mg PO daily | Chronic -all SCD patients | Chronic hemolysis depletes folate stores. Prevents megaloblastic crisis. |
📋 On Rounds
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?
Simple transfusion (give pRBCs to raise Hgb): VOC with Hgb significantly below baseline, symptomatic anemia, aplastic crisis (parvovirus B19), splenic sequestration. Target Hgb ≤ 10 (never higher -hyperviscosity).
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
VOC Management
Multimodal pain: IV opioids (hydromorphone 0.5 mg q2h PRN) + ketorolac + acetaminophen. Treat pain within 30 min of arrival. IVF with D5 1/2NS.
ACS
Fever + new infiltrate + respiratory symptoms. #1 cause of death. Management: exchange transfusion, antibiotics (ceftriaxone + azithro), IS q2h, bronchodilators.
IS Compliance
Incentive spirometry 10 breaths q2h while awake -prevents ACS. Reduced ACS from 36% to 0% in one study IS for ACS Prevention Trial, 1995.
Transfusion Rules
Simple: for symptomatic anemia, Hgb significantly below baseline. Exchange: for ACS, stroke, multiorgan failure. Target Hgb ≤ 10 (hyperviscosity).
Hydroxyurea
Disease-modifying: increases HbF → reduces sickling. Reduces VOC frequency, ACS, transfusion needs, mortality. All adults with SCD should be on it.
Infection / Sepsis
Functional asplenia → vulnerable to encapsulated organisms. Fever ≥ 38.3°C = emergency → ceftriaxone 2g IV within 1h. #1 killer: S. pneumoniae. Osteomyelitis: Salmonella (#1, not S. aureus). Dog/cat bite: Capnocytophaga → fulminant sepsis/DIC.
Vaccines & Prophylaxis
PCV13 + PPSV23, MenACWY + MenB, Hib, annual influenza. Penicillin VK prophylaxis through age 5 PROPS, 1986. Dog/cat bites → immediate amoxicillin-clavulanate.
Stroke
Children: ischemic (large vessel) -transcranial Doppler screening annually age 2-16. High TCD velocity → chronic exchange transfusion program (secondary prevention).
📄 One Pager
Sickle Cell -Quick Reference Card
SICKLE CELL -AT A GLANCE
🔥 Fever: ≥ 38.3°C = emergency → blood cultures + ceftriaxone 2g IV within 1h. Functional asplenia = no time to wait.
💉 Pain (VOC): IV hydromorphone PCA + ketorolac + acetaminophen. Treat within 30 min. IVF D5 1/2NS 1.5× maintenance.
🫁 ACS: New CXR infiltrate + fever/cough/hypoxia. #1 cause of death. Ceftriaxone + azithro. Exchange transfusion if severe.
🩸 Transfusion: Simple if Hgb < 7 or ≥ 2 below baseline. Exchange for ACS/stroke/MOF. Target Hgb ≤ 10 (never higher!).
🦠 Bugs to know: S. pneumoniae (#1 killer), Salmonella (osteomyelitis), Capnocytophaga (dog/cat bite → fulminant sepsis).
💊 Hydroxyurea: All adults with SCD. ↑ HbF → ↓ crises, ACS, mortality. 15–35 mg/kg/day. Monitor CBC q4–8wk.
🌬️ IS q2h: 10 breaths every 2 hours. Prevents ACS. Most important thing you can do during admission.
💉 Vaccines: PCV13 + PPSV23, MenACWY + MenB, Hib, annual flu. Penicillin VK prophylaxis age < 5.
💉 Pain (VOC): IV hydromorphone PCA + ketorolac + acetaminophen. Treat within 30 min. IVF D5 1/2NS 1.5× maintenance.
🫁 ACS: New CXR infiltrate + fever/cough/hypoxia. #1 cause of death. Ceftriaxone + azithro. Exchange transfusion if severe.
🩸 Transfusion: Simple if Hgb < 7 or ≥ 2 below baseline. Exchange for ACS/stroke/MOF. Target Hgb ≤ 10 (never higher!).
🦠 Bugs to know: S. pneumoniae (#1 killer), Salmonella (osteomyelitis), Capnocytophaga (dog/cat bite → fulminant sepsis).
💊 Hydroxyurea: All adults with SCD. ↑ HbF → ↓ crises, ACS, mortality. 15–35 mg/kg/day. Monitor CBC q4–8wk.
🌬️ IS q2h: 10 breaths every 2 hours. Prevents ACS. Most important thing you can do during admission.
💉 Vaccines: PCV13 + PPSV23, MenACWY + MenB, Hib, annual flu. Penicillin VK prophylaxis age < 5.
🧪 Workup
Workup
- CBC + retic -Hgb vs baseline
- Type & screen -extended phenotype matching
- CXR -new infiltrate = ACS
- Blood cultures if febrile
- LDH, indirect bili, haptoglobin
- TCD -stroke screening children 2-16
Heme/OncCommon
Transfusion Medicine
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
🚨 Management
Management
- Transfusion thresholds (restrictive):
- Hgb < 7 -most hospitalized patients [TRICC, 1999; TRISS, 2014; FOCUS, 2011]
- 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.
- Acute hemolytic: ABO incompatibility. Fever, flank pain, hemoglobinuria, DIC. STOP immediately. Aggressive IVF. Send workup.
- TRALI: bilateral infiltrates + hypoxia within 6h. Normal BNP. Supportive care (no diuretics -not volume overload). Resolves 48-72h.
- TACO: volume overload. Elevated BNP. Responds to furosemide. Prevention: slow rate, furosemide between units in high-risk.
- Allergic: urticaria (minor → diphenhydramine, resume). Anaphylaxis (IgA deficiency) → epinephrine, stop, use washed 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.
💊 Medications
Blood Products & Transfusion Medications
| Product / Drug | Indication & Threshold | Dose / Details |
|---|---|---|
| pRBCs (packed red blood cells) | Hgb < 7 (general, TRICC); Hgb < 8 (ACS / active cardiac ischemia) | 1 unit at a time. Expected rise: ~1 g/dL per unit. Recheck Hgb after each unit before ordering more. |
| Platelets | < 10K (prophylactic, no bleeding); < 50K (active bleeding or procedure); < 100K (neurosurgery) | 1 apheresis unit or 6-pack pooled. Expected rise: 30,000–50,000 per unit. Room temperature storage. |
| FFP (fresh frozen plasma) | INR > 1.5 with active bleeding. NOT for "correcting" INR without bleeding. | 15 mL/kg (~4 units for 70 kg). ABO-compatible required. ~30 min thaw time. Consider 4F-PCC for faster warfarin reversal. |
| Cryoprecipitate | Fibrinogen < 150 mg/dL (DIC, massive transfusion, post-thrombolytics) | 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
Threshold
Hgb < 7 for most [TRICC]. Hgb < 8 for ACS. 1 unit raises Hgb ~1 g/dL. Check after each unit before ordering more.
Massive Transfusion
MTP: 1:1:1 ratio (pRBC:FFP:plt). TXA 1g IV within 3h [CRASH-2]. Ca²⁺ repletion (citrate in products chelates Ca). Warm products.
TRALI vs TACO
TRALI: non-cardiogenic edema, normal BNP, no diuretics. TACO: volume overload, elevated BNP, responds to furosemide. BNP is the differentiator.
Febrile Reaction
Fever + rigors during transfusion. Stop. R/O hemolytic reaction: send DAT, free Hgb, LDH, haptoglobin. Most are benign febrile non-hemolytic reactions.
Prevention
Irradiate for immunocompromised (prevent TA-GVHD). CMV-negative for CMV-seronegative transplant patients. Slow rate for CHF/elderly (1 unit over 2-4h).
Type & Screen
Always before transfusion. Emergency: O-negative pRBC (universal donor). Type-specific uncrossmatched next. Full crossmatch safest but takes time.
📄 One Pager
Transfusion Medicine -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.
TRANSFUSION MEDICINE -AT A GLANCE
🩸 Thresholds: Hgb < 7 (general), < 8 (ACS). Platelets < 10K (prophylactic). FFP for INR > 1.5 + bleeding.
🧪 Workup: Type & screen, crossmatch, CBC, coags, post-transfusion Hgb 1h after → see Workup tab
⚠️ Reactions: STOP transfusion first. TRALI (normal BNP) vs TACO (elevated BNP) → see Reactions tab
💊 Products: pRBC, platelets, FFP, cryo, TXA → see Medications tab
📈 Monitor: Vitals q15min × 1h, watch for reactions, post-transfusion Hgb → see Monitoring tab
📣 Present: Indication, product, reaction workup → see Rounds tab
🧪 Workup: Type & screen, crossmatch, CBC, coags, post-transfusion Hgb 1h after → see Workup tab
⚠️ Reactions: STOP transfusion first. TRALI (normal BNP) vs TACO (elevated BNP) → see Reactions tab
💊 Products: pRBC, platelets, FFP, cryo, TXA → see Medications tab
📈 Monitor: Vitals q15min × 1h, watch for reactions, post-transfusion Hgb → see Monitoring tab
📣 Present: Indication, product, reaction workup → see Rounds tab
📄 One Pager
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].
🚨 Reactions
Febrile non-hemolytic (most common): stop, workup, rule out hemolytic. Acute hemolytic: fever + hypotension + back pain → stop immediately, send DAT, free Hgb, haptoglobin. TRALI: non-cardiogenic edema (normal BNP). TACO: volume overload (high BNP → furosemide).
💊 Special Products
Irradiated: immunocompromised (prevent TA-GVHD). CMV-negative: CMV-seroneg transplant patients. Leukoreduced: prevent febrile reactions. Washed: severe allergic reactions (IgA deficiency).
💊 Key Drugs
pRBCs1 unit raises Hgb ~1 g/dL
FFP10-15 mL/kg (INR correction)
Platelets1 unit raises plt ~30-50K
TXA1g IV (massive hemorrhage)
⚠️ Pitfalls
- Transfusing above threshold without indication
- Not checking type & screen
- Not recognizing TRALI vs TACO (BNP differentiates)
- Rapid transfusion in CHF/elderly (slow rate, furosemide between units)
RoundsRx · Hematology
AABB Guidelines 2016 · TRICC · TRISS · CRASH-2
EmergentHeme/Onc
HIT (Heparin-Induced Thrombocytopenia)
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)
| 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
🧪 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
4T Score
Thrombocytopenia (timing, fall > 50%), Timing (days 5-10), Thrombosis (new), oTher causes excluded. Score ≥ 6 = high probability → act immediately.
Immediate Actions
Stop ALL heparin (drips, flushes, line locks). Start argatroban. Bilateral LE duplex (30-50% have occult DVT). Send PF4 antibody + SRA.
Anticoagulation
Argatroban 2 mcg/kg/min IV (reduce in liver failure). Alternative: bivalirudin. NO LMWH (90% cross-reactivity).
Warfarin Timing
Do NOT start until plt ≥ 150K (risk of venous limb gangrene from protein C depletion). Overlap with argatroban ≥ 5 days.
Labs
PF4 antibody (screening, high NPV). SRA (serotonin release assay -confirmatory, high specificity). Don't wait for SRA to treat if high 4T score.
Duration
If no thrombosis: anticoag × at least 4 weeks after plt recovery. If thrombosis (HITT): anticoag × 3 months minimum.
📄 One Pager
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)
RoundsRx · Hematology
ASH HIT 2018
EMERGENTHeme/Onc
Neutropenic Fever
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
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)
- Consider fungal markers (galactomannan, β-D-glucan) if prolonged neutropenia (> 7 days)
🚨 Management
Empiric Antibiotics -Within 60 Minutes
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.
Management:
- Cefepime 2g IV q8h (anti-pseudomonal coverage)
- ADD vancomycin 25-30 mg/kg loading dose (suspected catheter-related infection)
- 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.
- Daily clinical assessment -new symptoms (cough, diarrhea, skin changes, abdominal pain), line sites (erythema, drainage), perianal exam, oral mucositis grade
- Galactomannan + β-D-glucan at day 4-5 if fever persists -repeat twice weekly if high suspicion for invasive fungal infection
- CRP trending -useful adjunct for tracking infection response (if rising on day 3-4, consider broadening coverage)
- Cr + LFTs -drug toxicity monitoring (vancomycin nephrotoxicity, voriconazole hepatotoxicity)
- Trough levels -vancomycin AUC/MIC targeting, voriconazole trough 1-5.5 mcg/mL
⚡ Summary
Summary
Definition
ANC < 500 (or expected to fall to < 500) + single temp ≥ 38.3°C or sustained ≥ 38.0°C over 1 hour.
First-Line
Cefepime 2g IV q8h. Monotherapy. Start within 1 hour of fever. Don't add vancomycin unless specific indication.
Add Vancomycin
Hemodynamic instability, catheter infection, skin/soft tissue infection, gram-positive bacteremia, mucositis.
Add Antifungal
Persistent fever at day 4-5 on antibiotics → micafungin or caspofungin. Galactomannan and β-D-glucan to guide.
MASCC Score
≥ 21 = low risk → outpatient oral abx (ciprofloxacin + amox-clav) if reliable patient, no organ dysfunction, close follow-up.
Stop Abx When
ANC > 500 rising + afebrile ≥ 48h + cultures negative + clinically stable. Don't continue indefinitely.
📄 One Pager
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)
- Not considering antifungal at day 4-5
RoundsRx · Oncology / ID
IDSA Neutropenic Fever 2010 · ASCO 2018
Rotation
Hematology / Oncology
Blood disorders, coagulopathies, oncologic emergencies, and transfusion medicine.
Available Topics
Neutropenic Fever
DIC
TTP / HUS
Tumor Lysis Syndrome
Sickle Cell
Transfusion Medicine
Transfusion Reactions
HIT
ITP
Oncologic Emergencies
Pancytopenia
Chemo Toxicities
Lymphoma
Multiple Myeloma
Acute Leukemia (AML/ALL)
Anticoagulation Management
Anemia Workup
Hemolytic Anemia
Superior Vena Cava Syndrome
Hyperviscosity Syndrome
Hypercalcemia of Malignancy
Amyloidosis
Massive Transfusion Protocol
ICU / Heme
📋 Major Guidelines
EndocrinologyCommon
Inpatient Insulin Management
Every intern needs this. Basal-bolus-correction replaces the sliding scale. Target glucose 140–180 mg/dL in most ICU patients and 100–180 on the floor (ADA 2026). Initiate insulin for persistent BG ≥ 180 confirmed ×2. The sliding scale alone is reactive, not proactive — it chases hyperglycemia instead of preventing it.
🔍 Overview
Glucose Targets
| Setting | Target | Evidence |
|---|---|---|
| ICU | 140–180 mg/dL | NICE-SUGAR, 2009: tight control (81–108) increased mortality vs moderate (140–180). Do NOT target normal glucose in critically ill patients. |
| General wards | 100–180 mg/dL (premeal < 140) | ADA 2026 Standards of Care. Initiate insulin for persistent BG ≥ 180 mg/dL confirmed on two occasions. Avoid > 180 and < 70. |
| Perioperative | 100–180 mg/dL | ADA 2026 NEW: A1c goal < 8% within 3 months of elective surgery (or TIR > 50%). Target BG 100–180 mg/dL before, during, and after procedures. Do NOT postpone surgery based on A1c alone. |
Sliding scale insulin alone is NOT appropriate inpatient management. It only reacts to hyperglycemia after it happens. Basal-bolus-correction proactively prevents glucose swings and reduces hypoglycemia, hyperglycemia, and length of stay RABBIT 2, 2007.
Key Rules
- Hold metformin if: eGFR < 30 (hold regardless), eGFR 30–44 (hold day of contrast, resume 48h later if stable), or acute illness with AKI risk. Updated: Old Cr-based cutoffs (1.5/1.4) are outdated — use eGFR. Metformin is safe with contrast if eGFR ≥ 45 per ACR, 2022.
- Hold SGLT2 inhibitors -risk of euglycemic DKA in acutely ill patients
- Hold sulfonylureas -unpredictable oral intake → hypoglycemia risk
- Insulin is the preferred agent for inpatient glucose management
- Type 1 diabetics always need basal insulin -never hold it completely or they develop DKA
💊 Basal-Bolus-Correction Protocol
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) |
| Insulin-naive, Type 2 | 0.4–0.5 units/kg/day (start conservatively). Elderly/CKD/thin → 0.3 units/kg/day. |
| Type 1 | 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
| Component | % of TDD | Agent | Details |
|---|---|---|---|
| Basal | 50% of TDD | Glargine (Lantus) or Detemir (Levemir) | Given once daily (glargine) or BID (detemir). Covers fasting glucose. Give at same time each day. Do NOT hold if NPO -reduce by 20–50% but never to zero (Type 1 ALWAYS needs basal). |
| Nutritional (bolus) | 50% of TDD, divided across meals | Lispro (Humalog) or Aspart (NovoLog) | Given before each meal. Skip if NPO or not eating. Split equally across 3 meals (each dose = TDD/6). |
| Correction | Added to nutritional dose | Same rapid-acting insulin | Correction factor ≈ 1800 / TDD (the "1800 rule"). Example: TDD = 60 → correction factor = 30 mg/dL per unit. Added on top of nutritional dose before meals. |
Step 3 -Adjust Daily
- Fasting glucose high? → increase basal by 10–20%
- Pre-lunch/dinner/bedtime high? → increase prior meal's nutritional dose by 10–20%
- 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? → can use basal + correction q6h, or 70/30 insulin for continuous feeds
Example: 80 kg Type 2, insulin-naive. TDD = 0.4 × 80 = 32 units. Basal = 16 units glargine at bedtime. Nutritional = 16 ÷ 3 = ~5 units lispro before each meal. Correction factor = 1800/32 = ~56 → 1 unit for every 56 mg/dL above target. Adjust daily based on glucose log.
ICU -Insulin Drip
- Continuous insulin infusion for critically ill patients (DKA, postoperative, unstable PO intake)
- Regular insulin drip: start 0.5–1 unit/hr, titrate to target 140–180
- Check BG q1h until stable, then q2h
- When transitioning to SubQ: give basal insulin 2–4 hours before stopping drip (basal takes time to reach steady state). If glargine → overlap 4h. If detemir → overlap 2h. Calculate basal from drip rate: 24-hr drip total × 80% = TDD → 50% as basal.
🔄 Updated Practice: Old teaching (Van den Berghe, 2001): tight glucose control (80-110 mg/dL) in ICU improves mortality. This was OVERTURNED by NICE-SUGAR, 2009 -intensive insulin INCREASED mortality due to hypoglycemia. Current target: glucose ≤180 mg/dL in ICU patients. Avoid both hyperglycemia AND hypoglycemia. Sliding scale insulin alone is also outdated -basal-bolus is superior (RABBIT 2, 2007).
RoundsRx Licensed Content - Unauthorized Use Prohibited📋 On Rounds
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 mg/dL). Tight control increased 90-day mortality (27.5% vs 24.9%) and increased severe hypoglycemia 13-fold. The likely mechanism: repeated hypoglycemic episodes → adrenergic surges, cardiac arrhythmias, and cerebral glucose deprivation. Before NICE-SUGAR, the Van den Berghe, 2001 (Leuven)
Why must you overlap basal insulin with the drip when transitioning?
Long-acting basal insulin (glargine, detemir) takes several hours to reach therapeutic levels after SubQ injection. Glargine takes ~4h to reach steady state; detemir ~2h. If you stop the insulin drip and give SubQ basal simultaneously, there's a gap of several hours with no effective insulin → rebound hyperglycemia → DKA risk (especially in Type 1).
Why is sliding-scale-only insulin dangerous in Type 1 diabetes?
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) and contains no basal component. A Type 1 patient on sliding-scale-only will: (1) have persistent hyperglycemia (only corrected q6h, then rises again), (2)
How do you transition from an insulin drip to subcutaneous insulin?
The overlap method: (1) Calculate 24h insulin drip requirement (last 6-8h average rate × 24). (2) Give 80% of this as daily basal insulin (glargine or detemir). (3) Give the first SubQ basal dose 2 HOURS before stopping the drip -this allows SubQ absorption to reach therapeutic levels before IV is discontinued. If you stop the drip first, there's a gap with no insulin → hyperglycemia or DKA (especially Type 1). (4)
What is the most common cause of inpatient hypoglycemia?
Mismatch between insulin and nutrition -patient made NPO but mealtime insulin not held, or reduced oral intake without dose adjustment. Always reassess insulin when diet order changes.
A 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). NEVER hold basal insulin entirely in a Type 1 diabetic -they will develop DKA. Hold all mealtime bolus. Use correction scale q4-6h PRN.
Why is NPH insulin specifically useful for steroid-induced hyperglycemia?
NPH peaks at 6-8 hours, which matches the hyperglycemic peak from morning prednisone. Give NPH with the AM steroid dose. Glargine is flat and doesn't match the steroid pattern.
What glucose target does NICE-SUGAR recommend for ICU patients?
140-180 mg/dL NICE-SUGAR, 2009. Intensive control (81-108) increased mortality by 14%, primarily from hypoglycemia. Tight control is harmful in the ICU.
Clinical Examples
📋 Case 1 — T2DM NPO for Surgery on Sliding Scale Only
Patient: 64M with T2DM (A1c 9.2), home meds metformin + glipizide. Admitted for cholecystectomy, NPO since midnight. Glucose range 240-380 mg/dL on sliding scale alone × 12h. No basal insulin ordered.
Key findings: Sliding-scale-only insulin is reactive, not proactive — it chases hyperglycemia without preventing it. Patient needs basal-bolus insulin. Home orals should be held (metformin: contrast/NPO risk; glipizide: unpredictable with NPO).
Management:
- Estimate TDD: weight-based 0.4 U/kg/day (conservative for insulin-naive) = ~36 U for 90 kg patient
- 50% as basal: glargine 18 U at bedtime
- Hold mealtime insulin while NPO — use correction scale q6h only (1800/36 = correction factor 50 mg/dL per unit)
- When eating: add mealtime lispro (remaining 50% ÷ 3 meals = 6 U before each meal)
- Target glucose 140-180 mg/dL (non-ICU floor target)
Teaching point: "Sliding scale only" is the #1 inpatient insulin error. It treats hyperglycemia after the fact but never prevents it. Every patient with persistent glucose > 180 needs scheduled basal insulin, not more correction doses.
📋 Case 2 — Type 1 DM Transitioning from Insulin Drip
Patient: 28F with T1DM, admitted in DKA (resolved). Insulin drip at 3 U/hr × last 8 hours. Gap closed, tolerating PO. Team wants to stop drip and start SubQ insulin.
Key findings: T1DM = ZERO endogenous insulin. If drip stops without overlap, DKA can recur within 6-12 hours. The transition must be seamless — never have a gap in insulin coverage.
Management:
- Calculate 24h drip requirement: 3 U/hr × 24h = 72 U/day
- Give 80% as daily basal: glargine 58 U SubQ (reduce slightly for safety)
- Give SubQ basal dose 2 HOURS before stopping the drip (overlap — glargine needs 4h to reach steady state)
- Add mealtime lispro: start at 6-8 U before meals + correction scale
- Check BG before each meal + bedtime + 3 AM for first 24h post-transition
Teaching point: The 2-hour overlap is non-negotiable. Give SubQ basal insulin WHILE the drip is still running. Stopping the drip first creates a dangerous insulin gap. In T1DM, this gap → DKA recurrence within hours.
📋 Case 3 — Steroid-Induced Hyperglycemia
Patient: 72F admitted for COPD exacerbation, started on prednisone 40 mg daily. No diabetes history. Glucose: fasting 110 → peaks 320 at 4 PM → 280 at bedtime → fasting 130 next morning.
Key findings: Steroid-induced hyperglycemia: prednisone peaks at 4-6h → hyperglycemia peaks in afternoon/evening. Fasting glucose relatively normal (steroids wear off overnight). This pattern is classic and missed by morning-only glucose checks.
Management:
- NPH insulin with AM prednisone dose: start 0.1-0.2 U/kg (NPH peaks at 6-8h — matches steroid hyperglycemia timing)
- Correction scale with mealtime lispro for lunch and dinner (afternoon/evening peaks)
- Do NOT use glargine alone (flat profile doesn't match the steroid pattern — causes overnight hypoglycemia while missing afternoon peaks)
- Titrate NPH by 2-4 U daily based on afternoon/evening glucose
- Taper insulin as steroid dose decreases — halve insulin when steroid dose is halved
Teaching point: NPH is the ideal insulin for steroid-induced hyperglycemia because its peak matches the steroid hyperglycemia peak. Glargine (flat profile) is the wrong choice — it doesn't match the pattern and risks overnight hypoglycemia. Always co-taper insulin with steroids.
📣 Sample Presentation
One-Liner
"Mrs. Chen is a 62-year-old with T2DM (A1c 9.8) on metformin + glipizide at home, now admitted for cholecystitis and NPO pre-operatively. Glucose range 220-380 over last 12 hours on sliding scale alone."
Key Points to Cover on Rounds
Hyperglycemia on sliding scale only -need basal-bolus conversion. Home: metformin (held for NPO/surgery) + glipizide (held -hypoglycemia risk while NPO). Weight 85 kg. Starting basal-bolus: glargine 0.3 units/kg/day = 25 units at bedtime (conservative -NPO). No nutritional insulin while NPO. Correction scale: q6h with lispro per sensitivity factor. Target glucose: 140-180. If eating → add mealtime lispro. Avoid sliding-scale-only (reactive, doesn't prevent hyperglycemia). Plan: adjust basal by 20% based on fasting glucose trend, transition back to home regimen post-op when eating.
🧪 Workup
Workup
- A1c -on admission for ALL diabetic patients and any glucose > 140. Reflects 3-month average. A1c > 9% = severe uncontrolled DM requiring basal-bolus.
- Fingerstick glucose -AC (before meals) + HS (bedtime) = 4×/day. Add q2h if on insulin drip or hypoglycemic.
- BMP -K⁺ (insulin shifts K intracellularly), Cr (dose-adjust), glucose trend
- Home medication reconciliation -exact doses of home insulin (basal type, units, timing), oral agents. Hold metformin if Cr > 1.5 or contrast planned. Hold SGLT2i inpatient (euglycemic DKA risk).
- Assess for DKA/HHS -if glucose > 300: check AG, ketones/BHB, osmolality, VBG
- Nutrition status -is patient eating? NPO? Tube feeds? TPN? This determines the insulin regimen.
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Glargine (Lantus) | 0.15-0.25 U/kg once daily | SQ | Basal insulin -backbone of inpatient regimen. Give at same time daily. Do NOT hold for NPO status -reduce to 60-80%. |
| Lispro (Humalog) | 0.05-0.1 U/kg per meal | SQ | Mealtime bolus -give with first bite. Hold if not eating. |
| Aspart (NovoLog) | 0.05-0.1 U/kg per meal | SQ | Alternative rapid-acting. Same dosing as lispro. |
| NPH insulin | 0.1-0.2 U/kg with AM steroid | SQ | Steroid-induced hyperglycemia. NPH peak at 6-8h matches steroid effect. Steroid Hyperglycemia NPH Study, 2017 |
| Regular insulin drip | 0.1 U/kg/hr (DKA protocol) | IV | ICU only. Transition to SQ 2h before stopping drip with basal overlap. |
| D50 (dextrose 50%) | 25g (50 mL) IV push | IV | Severe hypoglycemia (< 50 mg/dL or symptomatic). Follow with D10 drip if recurrent. |
| Glucagon | 1 mg IM/SQ | IM | No IV access. Onset 10-15 min. Causes nausea. Less effective in liver failure/alcohol. |
⚡ Summary
Summary
Basal-Bolus
Basal: glargine/detemir (background 24/7). Bolus: lispro/aspart before meals. Correction: q6h sliding scale. NEVER sliding scale alone.
Type 1 Rule
ALWAYS needs basal insulin -even if NPO. Reduce by 20-30% when NPO but NEVER hold. DKA develops in hours without basal insulin.
Starting Dose
Total daily dose: 0.3-0.5 units/kg/day. Give 50% as basal, 50% divided among meals. Lower in elderly, CKD, liver disease.
Drip to SubQ
Calculate 24h drip rate → give 80% as daily basal. Give SubQ dose 2 HOURS before stopping drip (overlap for absorption).
Target Glucose
140-180 mg/dL for most ICU patients NICE-SUGAR, 2009. Tight control (80-110) increased mortality. Avoid hypoglycemia.
Steroid Hyperglycemia
Steroids cause afternoon/evening hyperglycemia (not fasting). Increase mealtime insulin (especially lunch/dinner), NOT just basal. NPH can be paired with prednisone dosing.
📄 One Pager
Toxicology & Overdose -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.
TOXICOLOGY & OVERDOSE -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
⚡ Management
Management -Inpatient Insulin Management
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
EMERGENTEndocrinology
Thyroid Storm & Myxedema Coma
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
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.
| Feature | Score Range |
|---|---|
| Temperature | 99–99.9°F = 5 → 104+ = 30 |
| CNS effects | Agitation = 10, delirium = 20, seizure/coma = 30 |
| GI-hepatic dysfunction | Diarrhea/nausea = 10, jaundice = 20 |
| Heart rate | 100–109 = 5 → 140+ = 25 |
| CHF | Mild = 5, moderate = 10, severe = 15 |
| Afib | Present = 10 |
| Precipitant | Positive = 10 |
≥ 45: highly suggestive → treat as thyroid storm. 25–44: impending storm. < 25: unlikely.
Treatment -Order Matters
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)
- Bradycardia, hypotension
- Hypoventilation (CO₂ retention -blunted respiratory drive)
- Hyponatremia (↓ free water excretion -can be severe)
- Non-pitting edema (myxedema), delayed reflexes, ileus
- Triggers: infection (#1), cold exposure, surgery, opioids/sedatives, medication non-adherence
Treatment
| Drug | Dose | Notes |
|---|---|---|
| IV Levothyroxine (T4) 1ST LINE | 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?
PTU blocks thyroid hormone synthesis (inhibits thyroid peroxidase → can't organify iodine → can't make T3/T4). Iodine acutely blocks thyroid hormone RELEASE (Wolff-Chaikoff effect -excess iodine paradoxically inhibits hormone release).
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.
Management:
- PTU 200 mg PO/PR q4h (blocks synthesis AND peripheral T4→T3 conversion)
- SSKI 5 drops q6h started 1 HOUR after first PTU dose (Wolff-Chaikoff effect blocks release)
- Propranolol 60-80 mg PO q4-6h (symptom control + blocks T4→T3 conversion)
- Hydrocortisone 100 mg IV q8h (prevents relative adrenal insufficiency + blocks conversion)
- 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).
Management:
- Initiate thyroid storm protocol: PTU + iodine (1h later) + propranolol + hydrocortisone
- 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.
Management:
- Amiodarone-induced thyrotoxicosis type 2 (destructive thyroiditis) — decreased vascularity + elevated CRP
- 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.
- Burch-Wartofsky Score -≥ 45 = thyroid storm. 25-44 = impending storm. Scores: temp, CNS effects, GI/hepatic, HR, CHF, AF, precipitant.
- CBC, BMP, LFTs, lipase -hepatic dysfunction common (elevated AST/ALT/bilirubin). Leukocytosis.
- Blood cultures -infection is the #1 precipitant. Must rule out.
- Cortisol / ACTH stim -relative adrenal insufficiency common in storm. Stress-dose steroids given empirically.
- CXR, UA, lipase -search for precipitant (infection, surgery, trauma, iodine load, DKA, PE)
- 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
- 4. Block T4→T3 conversion: Hydrocortisone 100 mg IV q8h (also treats relative adrenal insufficiency) [Burch & Wartofsky]
- 5. Supportive: Cooling (acetaminophen, cooling blankets -NOT aspirin which displaces T4 from TBG), IVF, electrolyte repletion, ICU admission
- Treat the precipitant: antibiotics if infection, etc.
- Cholestyramine 4g QID -binds thyroid hormone in gut (adjunctive in refractory storm)
Do NOT give aspirin -it displaces T4 from thyroid-binding globulin, increasing free T4 and worsening storm. Use acetaminophen for fever.
📋 Clinical Example -Thyroid Storm Management
- Patient: 35F with known Graves' disease (non-compliant with methimazole), presents with fever 39.8°C, HR 162, agitation, vomiting, diarrhea. Burch-Wartofsky Score: 65 (>45 = thyroid storm).
- Treatment ORDER matters (block synthesis → block release → block conversion → block effects):
- 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.
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| PTU | 200 mg q4h | PO/PR | First-line thionamide. Blocks synthesis AND peripheral T4→T3 conversion. Risk: hepatotoxicity, agranulocytosis. |
| Methimazole (Tapazole) | 20 mg q4-6h | PO/PR | 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
Diagnosis
Burch-Wartofsky score ≥ 45 = storm. Fever + tachycardia + AMS + precipitant (surgery, infection, non-adherence) + known thyroid disease.
Treatment Order
(1) PTU 200 q4h → (2) Iodine 1 HOUR after PTU (Wolff-Chaikoff) → (3) Propranolol 60 q6h → (4) Hydrocortisone 100 q8h → (5) Acetaminophen (NOT aspirin).
Why Not Aspirin
Displaces T4 from TBG → increases free T4 → worsens storm. Use acetaminophen + cooling blankets for fever.
PTU vs Methimazole
PTU preferred in storm: blocks synthesis AND peripheral T4→T3 conversion. Methimazole only blocks synthesis.
Supportive
ICU. Aggressive IVF. Cooling blankets. Treat precipitant (infection, surgery). Nutritional support (high caloric needs).
Discharge
Transition to methimazole (lower hepatotoxicity). Endocrinology follow-up. Definitive treatment: RAI or thyroidectomy.
📄 One Pager
Endocrine / ICU · One Pager
Thyroid Storm
Burch-Wartofsky ≥ 45. Treatment ORDER matters: PTU → iodine 1h later → propranolol → hydrocortisone → acetaminophen (NOT aspirin). ICU.
🧪 Diagnosis
Burch-Wartofsky score ≥ 45 = storm. Fever + tachycardia out of proportion + AMS/agitation + known thyroid disease + precipitant (surgery, infection, iodine load, non-adherence).
🚨 Treatment Order
(1) PTU 200 mg q4h (blocks synthesis + T4→T3 conversion). (2) Iodine (SSKI) 1 HOUR after PTU (Wolff-Chaikoff). (3) Propranolol 60 mg q6h (symptom control + blocks conversion). (4) Hydrocortisone 100 mg q8h. (5) Acetaminophen for fever (NOT aspirin).
⚠️ Why This Order
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)
RoundsRx · Endocrine / ICU
ATA Thyrotoxicosis 2016 · Burch-Wartofsky Score
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.
- Fatigue, nausea, vomiting, abdominal pain, fever
- Eosinophilia -cortisol normally suppresses eosinophils. Low cortisol → eosinophil count rises.
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.
- ACTH level: ↑ ACTH = primary (adrenal failure). ↓ ACTH = secondary (pituitary failure).
- In crisis: draw cortisol and ACTH, then treat immediately. Do NOT wait for results.
🚨 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.
- Do NOT give dexamethasone if you want to check a cortisol level (dexamethasone doesn't cross-react with cortisol assay, but hydrocortisone does).
- 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). (4)
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.
How do you differentiate primary from secondary adrenal insufficiency?
ACTH level: High ACTH + low cortisol = primary (Addison's -adrenal gland destroyed). Low ACTH + low cortisol = secondary (pituitary failure or chronic steroid use). Hyperkalemia occurs only in primary (mineralocorticoid deficiency).
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.
- ACTH level -high ACTH + low cortisol = primary (Addison's). Low ACTH + low cortisol = secondary (pituitary/hypothalamic) or chronic steroid use.
- BMP -classic: hyponatremia + hyperkalemia (primary AI only -mineralocorticoid deficiency). Also hypoglycemia, mild hypercalcemia.
- CBC -eosinophilia (cortisol normally suppresses eosinophils)
- TSH -hypothyroidism common in autoimmune polyglandular syndrome. Treat cortisol BEFORE thyroid hormone (levothyroxine can precipitate crisis).
- CT adrenals -hemorrhage (anticoagulation, Waterhouse-Friderichsen), metastases, infiltration (TB, histoplasmosis, sarcoid)
- 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
Crisis Treatment
Hydrocortisone 100 mg IV bolus immediately → 50 mg IV q8h. Don't wait for lab results. IVF with D5NS (hypoglycemia risk).
Primary vs Secondary
Primary (Addison): high ACTH, hyperpigmentation, hyperkalemia. Secondary: low ACTH, no hyperpigmentation, no hyperkalemia.
Most Common Cause
Chronic exogenous steroids → HPA suppression → abrupt withdrawal → crisis. Also: autoimmune (#1 primary), TB (#1 worldwide).
Cosyntropin Test
250 mcg IV → cortisol at 0, 30, 60 min. Normal: cortisol ≥ 18. Fails to stimulate → AI confirmed.
Stress Dosing
Minor illness: double home dose × 3 days. Major surgery: hydrocortisone 100 mg IV → 50 q8h × 24h → taper. Always carry emergency injection.
Medic Alert
All patients with adrenal insufficiency need medic alert bracelet + emergency injection kit + sick day rules written down.
📄 One Pager
Adrenal Insufficiency & Crisis -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.
ADRENAL INSUFFICIENCY & CRISIS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
📄 One Pager
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
RoundsRx · Endocrine
Endocrine Society AI 2016
EndocrinologyCommon
SIADH & Diabetes Insipidus
Two opposite disorders of water balance. SIADH: too much ADH → water retention → dilutional hyponatremia. DI: too little ADH (or resistance) → massive free water loss → hypernatremia. Correct slowly -osmotic demyelination kills.
💧 SIADH
Diagnostic Criteria -ALL Must Be Present
- Serum Na⁺ < 135 mEq/L (hyponatremia)
- Serum osmolality < 275 mOsm/kg (hypo-osmolar)
- Urine osmolality > 100 mOsm/kg (inappropriately concentrated urine)
- Urine sodium > 40 mEq/L (kidneys wasting sodium)
- Euvolemic on clinical exam (no edema, no orthostasis)
- Normal thyroid and adrenal function (must rule out hypothyroidism and cortisol deficiency -both cause hyponatremia)
SIADH is a diagnosis of exclusion. You must rule out hypothyroidism (check TSH) and adrenal insufficiency (check AM cortisol) before diagnosing SIADH. Both cause hyponatremia and both are treatable with specific therapy.
Verbalis Expert Panel, 2013 Osmotic Demyelination Syndrome (ODS): if Na corrects too fast (> 8–10 mEq/L in 24h), myelin in the central pons is destroyed → "locked-in syndrome" (awake but unable to move or speak). Irreversible. Risk factors: chronic hyponatremia, alcoholism, malnutrition, hypokalemia, liver disease. If overcorrecting → give D5W + desmopressin (DDAVP) 2 mcg IV q8h to re-lower Na.
🔥 Diabetes Insipidus
Types
| Type | Mechanism | Causes | Urine Osm after DDAVP |
|---|---|---|---|
| Central DI | ↓ ADH production (posterior pituitary) | Neurosurgery (#1), pituitary tumors, head trauma, brain death, Sheehan syndrome, infiltrative (sarcoid, histiocytosis) | ↑↑ (concentrates > 50%) -kidneys respond to exogenous ADH |
| Nephrogenic DI | Kidney resistance to ADH | Lithium (#1 drug cause), hypercalcemia, hypokalemia, chronic kidney disease, demeclocycline | No change -kidneys don't respond |
Presentation & Diagnosis
- Polyuria (> 3 L/day of dilute urine -Uosm < 300)
- Polydipsia (intense thirst if alert)
- Hypernatremia (if unable to access water -ICU patients, post-neurosurgery, AMS)
- Urine osmolality < 300 with serum osmolality > 290 → inappropriate dilute urine
- Water deprivation test → distinguishes central vs nephrogenic (give DDAVP and measure urine osm response)
Treatment
| Type | Treatment | Notes |
|---|---|---|
| Central DI | Desmopressin (DDAVP) 1–2 mcg IV/SC q12h or 10–20 mcg intranasal BID | Replaces missing ADH. Monitor Na closely -risk of hyponatremia with overdose. Titrate to UOP. |
| Nephrogenic DI | Remove offending agent (lithium). Low-sodium diet + thiazide diuretic (paradoxically ↓ urine output). Amiloride for lithium-induced NDI. | DDAVP does NOT work (kidneys are resistant). Thiazide paradox: thiazides cause mild volume depletion → ↑ proximal reabsorption → less water delivered to collecting duct → less dilute urine. |
| Acute hypernatremia (from DI) | D5W or 0.45% NS IV. Free water deficit = TBW × (Na/140 − 1). | Correct ≤ 10 mEq/L per 24h if chronic. If acute (< 48h) → can correct faster. Replace ongoing free water losses (UOP) in addition to deficit. |
📋 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 ≤ 8–10 mEq/L in 24h. Immediate steps: (1) D5W infusion (free water to re-lower Na), (2) DDAVP 2 mcg IV q8h (replaces ADH → kidneys retain free water → Na drops back), (3) target Na back to no more than 8 mEq/L above the starting value for the 24h period. The goal is to "re-lower" the sodium to a safe correction trajectory.
Why do thiazides paradoxically help nephrogenic DI?
Counterintuitive but elegant: thiazides block NaCl reabsorption in the distal convoluted tubule → mild sodium and volume depletion → the body compensates by increasing proximal tubule reabsorption of sodium AND water → less water is delivered to the ADH-insensitive collecting duct → less dilute urine produced → lower urine volume. The effect reduces urine output by ~30–50%.
How does tolvaptan work and why must you start it inpatient?
Tolvaptan is a V2 receptor antagonist -blocks ADH (vasopressin) at the collecting duct → induces a free water diuresis (aquaresis) without sodium loss. Result: concentrated urine, dilute plasma → sodium rises. Must be started inpatient because the sodium correction can be unpredictable and rapid → risk of overcorrection → osmotic demyelination syndrome (ODS). Monitoring protocol: Na checked at 4-6h, 8-12h, and 24h after first dose.
What are the criteria for diagnosing SIADH?
Essential criteria (all must be met): (1) Serum osm < 275 mOsm/kg (hypoosmolar), (2) Urine osm > 100 mOsm/kg (inappropriately concentrated -the kidneys SHOULD be making dilute urine in hypo-osmolar state), (3) Euvolemic (no edema, no JVD, no orthostasis), (4) Urine Na > 40 mEq/L (kidneys excreting sodium inappropriately), (5)
A patient with Na 118 and seizures -what do you give and how fast do you correct?
3% hypertonic saline 100-150 mL bolus over 10 min. Can repeat ×1. Target 4-6 mEq/L rise in the first 4-6h. Do NOT exceed 8 mEq/24h (6 if high-risk). Overcorrection → osmotic demyelination syndrome.
What is the most dangerous time for osmotic demyelination syndrome (ODS)?
ODS presents 2-6 days after overcorrection with dysarthria, dysphagia, quadriparesis, and locked-in syndrome. Risk factors: chronic hyponatremia > 48h, alcoholism, malnutrition, liver disease, hypokalemia.
When should you give DDAVP in hyponatremia management?
As an ODS rescue -if Na is correcting too fast (> 8 mEq/24h or > 6 in high-risk). Give DDAVP 2 mcg IV q8h + D5W to re-lower sodium back to the safe correction rate.
Why must you check TSH and cortisol before diagnosing SIADH?
Both hypothyroidism and adrenal insufficiency cause hyponatremia and mimic SIADH (euvolemic, concentrated urine). They are treatable and MUST be excluded. 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/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 #1 drug cause of SIADH. Always check Na 2-4 weeks after starting an SSRI in elderly patients. 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 rising Na. Must watch for triphasic response.
Management:
- DDAVP 1 mcg IV q12h
- D5W to replace free water deficit + 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 ~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 (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, malignancy.
Management:
- STOP hypertonic saline immediately
- DDAVP 2 mcg IV q8h (re-lower Na)
- D5W infusion to bring Na back down
- Target: Na no more than 8 mEq/L above starting value for 24h period (goal Na ≤ 116)
- Na q2h until trending downward
Teaching point: ODS rescue (DDAVP + D5W) should be initiated immediately when overcorrection is detected. ODS presents 2-6 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."
Monitoring Parameters -Cellulitis & Skin Infections
| 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.
Key Points to Cover on Rounds
SIADH -euvolemic hypoosmolar hyponatremia with inappropriately concentrated urine and high UNa. Cause: sertraline (SSRIs are the most common drug cause of SIADH). Asymptomatic (no seizure, no AMS). Treatment: fluid restriction <1L/day started. Sertraline held -discuss alternative antidepressant with psychiatry. Na trending 122→124→126 over 36h (rate 3 mEq/24h -safe, goal ≤8 per 24h). Plan: if refractory to fluid restriction → salt tabs 1g TID. If still refractory → tolvaptan (inpatient only, check Na q6h). ODS rescue protocol available if overcorrected (D5W + DDAVP).
🧪 Workup
Diagnostic Evaluation -Cellulitis & Skin Infections
Workup checklist for Cellulitis & Skin Infections: History and physical → targeted labs → imaging as indicated → specialist consultation if needed. Always correlate clinically.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications, relevant PMH
- Physical exam: Focused exam relevant to cellulitis & skin infections presentation
- Labs: CBC, BMP, relevant disease-specific labs (see Overview tab for specifics)
- Imaging: As clinically indicated based on presentation
- Special studies: Consider disease-specific diagnostics (see Overview tab)
⚡ Management
Management -SIADH & Diabetes Insipidus
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
💊 Medications
Key Medications -Cellulitis & Skin Infections
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
⚡ Summary
Summary
Diagnostic Criteria
Serum osm < 275 + urine osm > 100 + euvolemic + UNa > 40 + normal thyroid/adrenal function + no diuretics. Diagnosis of exclusion.
Common Causes
SSRIs (#1 drug cause), carbamazepine, cyclophosphamide, vincristine. CNS: stroke, SAH, meningitis. Pulmonary: pneumonia, TB. Malignancy: SCLC.
Treatment
Fluid restriction < 1L/day (first-line) → salt tabs → tolvaptan (V2 antagonist, inpatient only, check Na q6h). Treat underlying cause.
Tolvaptan Rules
Start inpatient. No fluid restriction while on it. Check Na at 4-6h, 8-12h, 24h. Hold if correcting > 8 mEq/24h. Hepatotoxicity risk (max 30 days).
Correction Rate
≤ 8 mEq/L per 24h. High-risk for ODS: Na < 105, chronic, alcoholism, malnutrition, liver disease. In high-risk → ≤ 6 mEq/24h.
ODS Rescue
D5W + DDAVP 2 mcg IV q8h if overcorrecting. Act immediately. ODS = devastating irreversible pontine demyelination.
📄 One Pager
Cellulitis & Skin Infections -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.
CELLULITIS & SKIN INFECTIONS -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
EmergentEndocrinology
Hypercalcemia
"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. |
| Severe (hypercalcemic crisis) | > 14 mg/dL | AMS, stupor, coma, cardiac arrhythmias (short QT → Osborn waves → cardiac arrest), AKI, pancreatitis. |
Always correct for albumin: Corrected Ca = measured Ca + 0.8 × (4.0 − albumin). Or check ionized calcium (more accurate, especially in ICU patients).
Differential -The Two Big Ones
| Cause | % of Cases | PTH | Key Features |
|---|---|---|---|
| Primary hyperparathyroidism | ~55% (most common overall, #1 outpatient cause) | ↑ or inappropriately normal | Usually mild, chronic. Single adenoma (~85%). ↑ Ca, ↓ PO₄, ↑ urine Ca. Stones, osteoporosis. |
| Malignancy | ~35% (#1 inpatient cause) | ↓ (suppressed) | Usually severe, acute onset. Mechanisms: PTHrP secretion (squamous cell, RCC, breast → humoral hypercalcemia of malignancy), osteolytic metastases (breast, myeloma), calcitriol production (lymphoma). |
| Other (~10%) | Variable | Granulomatous disease (sarcoid → ↑ calcitriol), thiazides, lithium, vitamin D intoxication, milk-alkali syndrome, immobilization, thyrotoxicosis, Addison disease. |
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.
🚨 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).
- ECG -shortened QT interval. Severe: Osborn waves, bradycardia, heart block.
- 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
Branch Point
Check PTH first. Elevated → primary hyperparathyroidism. Suppressed → malignancy (check PTHrP), granulomatous disease (check 1,25-D), meds.
Outpatient #1
Primary hyperparathyroidism (elevated PTH + elevated Ca). Parathyroid adenoma most common. Surgery if symptomatic or meets criteria.
Inpatient #1
Malignancy: humoral (PTHrP -squamous, RCC, breast), osteolytic (myeloma, breast mets), 1,25-D production (lymphoma).
Treatment Order
(1) NS 200-300 mL/hr (most important), (2) calcitonin (fast, bridges to bisphosphonate, tachyphylaxis at 48h), (3) zoledronic acid (most effective, onset 2-4 days). No furosemide unless overloaded.
Severe Ca > 14
Aggressive hydration + calcitonin + zoledronic acid. ICU if cardiac symptoms, AMS, or severe dehydration. ECG: short QT.
Symptoms
Stones (renal), bones (pain, fractures), groans (abdominal pain, constipation, pancreatitis), moans (AMS, depression), overtones (polyuria, dehydration).
📄 One Pager
Endocrine / Oncology · One Pager
Hypercalcemia
PTH is the branch point. Outpatient #1: primary hyperparathyroidism. Inpatient #1: malignancy. NS hydration first → calcitonin → zoledronic acid. No furosemide unless overloaded.
🧪 Etiology -PTH Branch
PTH elevated: primary hyperparathyroidism (parathyroid adenoma). PTH suppressed: malignancy (PTHrP → squamous, RCC, breast), granulomatous disease (sarcoid, TB → 1,25-D), vitamin D toxicity, lytic bone mets.
🚨 Treatment
(1) NS 200-300 mL/hr (most important -rehydrate first). (2) Calcitonin 4 IU/kg IM q12h (fast onset, bridges to bisphosphonate, tachyphylaxis at 48h). (3) Zoledronic acid 4 mg IV over 15 min (most effective, onset 2-4 days).
⚠️ Symptoms -Stones, Bones, Groans, Moans
Stones (renal), Bones (pain, fractures), Groans (constipation, abd pain, pancreatitis), Moans (depression, AMS), Overtones (polyuria, dehydration, short QT).
💊 Key Drugs
NS200-300 mL/hr
Calcitonin4 IU/kg IM q12h
Zoledronic acid4 mg IV over 15 min
Denosumab120 mg SQ (if bisphosphonate fails)
⚠️ Pitfalls
- Furosemide for hypercalcemia (only if volume overloaded -most patients are dehydrated)
- Not checking PTH first (the diagnostic branch point)
- Delayed hydration
- Missing malignancy as cause in hospitalized patients
RoundsRx · Endocrine / Oncology
Endocrine Society PHPT 2022 · ASCO
Rotation
Endocrinology
Diabetes management, thyroid disorders, adrenal pathology, calcium disorders, and pituitary emergencies.
Available Topics
Inpatient Insulin Management
Thyroid Storm & Myxedema
Adrenal Crisis
SIADH & Diabetes Insipidus
Hypercalcemia
HHS (Hyperosmolar State)
Myxedema Coma
Pheochromocytoma
Inpatient Hypoglycemia
Hypocalcemia
Diabetes Insipidus
Cushing's Syndrome
Hyperthyroidism / Graves'
Primary Aldosteronism
Hypothyroidism
Hypoparathyroidism
📋 Major Guidelines
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
- ESR + CRP q3-6 months -inflammatory marker trending
- 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.
RoundsRx Licensed Content - Unauthorized Use Prohibited
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. |
| BIOLOGIC | TNF inhibitors (adalimumab, etanercept, infliximab) | 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-target TICORA, 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.
Key findings: CT chest: bilateral ground-glass opacities. PFTs: restrictive pattern with reduced DLCO. BAL: lymphocyte predominance, cultures negative. Mild eosinophilia.
Management:
- 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.
Management:
- Start latent TB treatment: isoniazid 300 mg daily + pyridoxine × 9 months
- Delay biologic by ≥ 1 month after starting TB treatment
- Continue methotrexate; bridge with low-dose prednisone if needed
- Monitor LFTs on INH + MTX (both hepatotoxic)
Teaching point: TNF-alpha maintains granuloma integrity. TNF inhibitors → granuloma breakdown → disseminated TB. Always screen with QuantiFERON before ANY biologic.
📋 Case 3 — RA Flare During Active Infection
Patient: 63-year-old woman on adalimumab + methotrexate admitted with cellulitis. Also has active RA flare with 6 swollen joints.
Key findings: WBC 14,000, CRP 12. Blood cultures negative. Cellulitis without abscess.
Management:
- 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 -Discharge Planning Checklist
| 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
- ESR + CRP q3-6 months -inflammatory marker trending
- 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
Diagnosis
≥ 6 points on ACR/EULAR 2010 criteria. Joint involvement + serology (RF, anti-CCP) + acute phase (CRP, ESR) + duration ≥ 6 weeks.
First-Line DMARD
Methotrexate 15-25 mg/week + folic acid 1 mg daily. Monitor: CBC, LFTs, Cr every 2-3 months.
Treat-to-Target
Goal: remission or low disease activity within 6 months. Reassess q3 months. If not at target → add biologic or JAK inhibitor.
Biologics
TNFi (adalimumab, etanercept), IL-6 (tocilizumab), T-cell (abatacept), B-cell (rituximab), JAKi (tofacitinib, upadacitinib).
Pre-Biologic Screen
QuantiFERON (TB), HBV/HCV serologies, CBC, LFTs, CXR. Update vaccines before starting. Annual flu + pneumococcal.
Don't Miss
Atlantoaxial instability (subluxation) -flexion/extension C-spine X-ray before intubation. Increased CV risk. Screen for ILD.
📄 One Pager
Rheumatology · One Pager
Rheumatoid Arthritis -Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
RHEUMATOID ARTHRITIS -AT A GLANCE
📋 Diagnosis: ACR/EULAR 2010 criteria (≥ 6 points). Symmetric small joint polyarthritis + RF/anti-CCP + elevated ESR/CRP + duration ≥ 6 weeks. Spares DIPs.
🧪 Workup: RF, anti-CCP (most specific ~95%), ESR, CRP, CBC, BMP, LFTs, HBV/HCV serologies, QuantiFERON (before biologics), hand/foot X-rays.
⚡ First-Line: Methotrexate 15-25 mg/week + folic acid 1 mg daily. Reassess q3 months. If not at target → add biologic.
💊 Biologics: TNFi (adalimumab, etanercept) · IL-6 (tocilizumab) · T-cell (abatacept) · B-cell (rituximab) · JAKi (tofacitinib, upadacitinib — after TNFi failure).
📈 Monitor: DAS28/CDAI q3 months. CBC + LFTs + Cr q8-12 weeks on MTX. Annual retinal exam on HCQ. QuantiFERON before biologics.
⚠️ Don't Miss: Atlantoaxial instability (C-spine X-ray before intubation). Increased CV risk. Screen for ILD. MTX is category X.
🧪 Workup: RF, anti-CCP (most specific ~95%), ESR, CRP, CBC, BMP, LFTs, HBV/HCV serologies, QuantiFERON (before biologics), hand/foot X-rays.
⚡ First-Line: Methotrexate 15-25 mg/week + folic acid 1 mg daily. Reassess q3 months. If not at target → add biologic.
💊 Biologics: TNFi (adalimumab, etanercept) · IL-6 (tocilizumab) · T-cell (abatacept) · B-cell (rituximab) · JAKi (tofacitinib, upadacitinib — after TNFi failure).
📈 Monitor: DAS28/CDAI q3 months. CBC + LFTs + Cr q8-12 weeks on MTX. Annual retinal exam on HCQ. QuantiFERON before biologics.
⚠️ Don't Miss: Atlantoaxial instability (C-spine X-ray before intubation). Increased CV risk. Screen for ILD. MTX is category X.
EmergentRheumatology
Antiphospholipid Syndrome
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.
Treatment
| Scenario | Treatment |
|---|---|
| Venous thrombosis (DVT/PE) | Warfarin INR 2–3, indefinite. No DOACs. |
| Arterial thrombosis (stroke, MI) | Warfarin INR 2–3 (some advocate INR 3–4 for arterial events, controversial). ± aspirin. |
| Obstetric APS (no thrombosis) | LMWH (enoxaparin prophylactic dose) + low-dose aspirin throughout pregnancy. |
| Catastrophic APS (CAPS) | Triple therapy: anticoagulation + high-dose steroids + plasma exchange or IVIG. Mortality ~50%. Multiorgan thrombotic microangiopathy. |
📋 On Rounds
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?
CAPS = rapid-onset multi-organ thrombotic microangiopathy in APS -affects ≥ 3 organs within 1 week. Mortality ~30-50%. Organs affected: renal (TMA/RPGN), CNS (stroke, seizures), cardiac (valve thrombosis, MI), pulmonary (PE, ARDS), skin (livedo, digital gangrene). Triggered by: infection (#1), surgery, anticoag withdrawal, SLE flare. Treatment = triple therapy: (1) Anticoagulation (heparin drip), (2)
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).
Management:
- Low-dose aspirin 81 mg daily — start preconception
- Prophylactic LMWH (enoxaparin 40 mg SQ daily) — add once pregnancy confirmed
- This regimen reduces pregnancy loss from ~70% to ~20-30%
- Monitor for preeclampsia, IUGR, and placental insufficiency
- Postpartum: continue anticoagulation × 6 weeks (high thrombosis risk peripartum)
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 -Discharge Planning Checklist
| 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).
- Triple positivity (all 3 positive) = highest thrombotic risk -lifelong anticoagulation, never stop.
- CBC -thrombocytopenia (20-40% of APS), hemolytic anemia (Coombs+)
- Peripheral smear -schistocytes if TMA component (catastrophic APS)
- Cr, LFTs -APS nephropathy, hepatic involvement
- Echocardiogram -Libman-Sacks endocarditis (non-bacterial vegetations, usually mitral valve)
- MRI brain -if neurological symptoms (stroke, TIA, cognitive dysfunction, seizures)
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Warfarin | Target INR 2-3 (arterial: 2.5-3.5) | PO | 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
Criteria
Thrombosis (arterial or venous) OR pregnancy morbidity + persistent antiphospholipid antibodies (positive × 2, ≥ 12 weeks apart).
3 Antibodies
Lupus anticoagulant (functional), anticardiolipin (IgG/IgM), anti-β2-glycoprotein I (IgG/IgM). Triple-positive = highest risk.
Treatment
Warfarin (INR 2-3) lifelong. DOACs contraindicated TRAPS, 2018. Add hydroxychloroquine (reduces thrombosis). Low-dose ASA for arterial events.
Pregnancy
Low-dose aspirin + LMWH throughout pregnancy. Warfarin is teratogenic -must switch to LMWH pre-conception.
CAPS
Catastrophic APS: multi-organ thrombosis in ≤ 1 week. Mortality 30-50%. Triple therapy: anticoag + steroids + PLEX/IVIG. Add rituximab if refractory.
Don't Forget
APS can be primary or secondary (SLE). Screen all SLE patients for aPL antibodies. Screen young strokes and unprovoked VTE.
⚡ 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.
📄 One Pager
Rheumatology / Hematology · One Pager
Antiphospholipid Syndrome
Thrombosis + persistent aPL antibodies (× 2, ≥ 12 weeks apart). Warfarin lifelong (no DOACs [TRAPS]). Triple-positive = highest risk. CAPS = ICU emergency.
🧪 Diagnosis
Thrombosis (arterial or venous) OR pregnancy morbidity + persistent aPL antibodies (positive ×2, ≥ 12 weeks apart). 3 antibodies: LA, aCL (IgG/IgM), anti-β2GP1 (IgG/IgM).
🚨 Treatment
Warfarin INR 2-3 (lifelong). DOACs are CONTRAINDICATED TRAPS, 2018. Add hydroxychloroquine (reduces thrombosis). ASA for arterial events. Pregnancy: LMWH + low-dose ASA.
⚠️ CAPS -Catastrophic APS
Multi-organ thrombosis in ≤ 1 week (≥ 3 organs). Mortality 30-50%. Triple therapy: anticoag + high-dose steroids + PLEX/IVIG. Add rituximab or eculizumab if refractory.
💊 Key Drugs
WarfarinINR 2-3 (lifelong)
Hydroxychloroquine200-400 mg daily
ASA81 mg daily (arterial events)
LMWH1 mg/kg BID (pregnancy)
⚠️ Pitfalls
- DOACs in APS (contraindicated -increased thrombosis [TRAPS])
- Single antibody test (need positive × 2, ≥ 12 weeks apart)
- Not screening SLE patients for aPL antibodies
- Missing CAPS (think of it in multi-organ thrombosis)
RoundsRx · Rheumatology / Hematology
EULAR APS 2019 · TRAPS 2018
EmergentRheumatology
Scleroderma & Renal Crisis
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.
🔍 Overview
Limited vs Diffuse
| Feature | Limited (CREST) | Diffuse |
|---|---|---|
| Skin involvement | Distal to elbows/knees + face | Proximal (trunk, upper arms, thighs) |
| Antibody | Anti-centromere | Anti-Scl-70 (topoisomerase I) |
| Internal organs | Pulmonary HTN (isolated PAH -screen with annual echo), esophageal dysmotility (GERD) | ILD (NSIP pattern), scleroderma renal crisis, cardiac fibrosis |
| Prognosis | Better (slower progression) | Worse (organ fibrosis -lungs, kidneys) |
| CREST | 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?
Limited (CREST): Calcinosis, Raynaud's, Esophageal dysmotility, Sclerodactyly, Telangiectasia. Antibody: anti-centromere. Key complication: pulmonary arterial hypertension (PAH) -screen with annual echo (RVSP). Skin involvement limited to distal extremities/face. Diffuse: widespread skin thickening (trunk + proximal extremities). Antibody: anti-Scl-70 (topoisomerase I) or anti-RNA polymerase III.
Why are steroids dangerous in 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 mofetil Scleroderma Lung Study II, 2016. Similar efficacy to cyclophosphamide with fewer side effects. Add nintedanib SENSCIS, 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
Limited (CREST)
Calcinosis, Raynaud, Esophageal dysmotility, Sclerodactyly, Telangiectasia. Ab: anti-centromere. Key risk: PAH. Skin: distal only.
Diffuse
Widespread skin thickening (trunk + proximal). Ab: anti-Scl-70, anti-RNA pol III. Key risks: ILD, renal crisis. Rapid progression.
Renal Crisis
HTN emergency + AKI + MAHA. Risk: steroids > 15 mg/day. Treatment: captopril (ACEi) -titrate aggressively, don't hold for rising Cr.
ILD Screening
HRCT + PFTs at diagnosis, then annually. FVC declining > 10% → immunosuppression (mycophenolate, nintedanib, tocilizumab).
PAH Screening
Annual echo (RVSP). If elevated → right heart catheterization for confirmation. Treatment: PDE5i, ERA, prostacyclins.
Steroids Danger
Prednisone > 15 mg/day precipitates renal crisis. Use sparingly. Monitor BP and Cr closely if steroids unavoidable.
📄 One Pager
One Pager -Antiphospholipid Syndrome
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
ANTIPHOSPHOLIPID SYNDROME -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
Rheumatology · One Pager
Systemic Sclerosis
Limited = CREST + PAH risk + anti-centromere. Diffuse = ILD + renal crisis + anti-Scl-70/anti-RNA pol III. Steroids > 15mg → renal crisis. Captopril for SRC.
🧪 Classification
Limited (CREST): Calcinosis, Raynaud, Esophageal, Sclerodactyly, Telangiectasia. Ab: anti-centromere. Key risk: PAH. Diffuse: widespread skin, Ab: anti-Scl-70/anti-RNA pol III. Key risks: ILD, renal crisis.
🚨 Scleroderma Renal Crisis
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).
💊 Key Drugs
Captopril6.25-50 mg TID (renal crisis)
Nifedipine30-90 mg daily (Raynaud)
Mycophenolate2-3g/day (ILD)
Nintedanib150 mg BID (ILD)
⚠️ Pitfalls
- Steroids > 15 mg/day (precipitates renal crisis)
- Not monitoring BP/Cr on steroids
- Beta-blockers (worsen Raynaud)
- Late ILD screening (PFTs + HRCT at diagnosis)
RoundsRx · Rheumatology
ACR/EULAR SSc 2013 · SENSCIS · focuSSced
CommonRheumatology
Acute Gout & Pseudogout
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. Anakinra Pericarditis Trial, 2019 |
Urate-Lowering Therapy (ULT) -Chronic
Do NOT start ULT during an acute flare -changing urate levels can prolong or worsen the attack. Start 2–4 weeks after flare resolution. However, do NOT stop ULT if already on it during a flare.
🔄 Updated Practice: Old teaching: never start allopurinol (Zyloprim) during an acute gout flare — it will prolong or worsen the attack. Current practice: it IS safe to start urate-lowering therapy during an acute flare, as long as anti-inflammatory cover (colchicine 0.6 mg daily or BID) is provided. Delaying ULT initiation by weeks leads to treatment gaps, missed opportunities, and worse long-term outcomes. Multiple RCTs have shown no increase in flare duration or severity when starting ULT with prophylaxis.
| 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. | 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 | Alternative if allopurinol intolerant or HLA-B*5801 positive. CARES, 2018: cardiovascular mortality signal → use only if allopurinol fails. |
Indications for ULT: ≥ 2 flares/year, tophi, urate nephropathy, CKD stage ≥ 3 wi
🧪 Workup
Workup
- 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.
Why can serum uric acid be normal during an acute gout flare?
Acute inflammation causes increased renal urate excretion (uricosuric effect of IL-6) and hemodilution from acute phase response. Up to 40% of patients have normal UA during flare. Check between flares for accurate baseline.
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 -DIC
| 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
Acute Flare
Colchicine 1.2 mg → 0.6 mg 1h later → 0.6 BID (low-dose AGREE, 2010). NSAIDs. Steroids if both contraindicated. Anakinra for refractory.
Crystal Diagnosis
Joint aspiration: negatively birefringent needle-shaped crystals under polarized light. WBC 2,000-50,000. Culture to rule out concurrent septic joint.
ULT Goal
Treat-to-target: uric acid < 6 mg/dL (< 5 if tophi). Allopurinol start 100 mg, titrate by 100 mg q2-4 weeks. Check HLA-B*5801 in at-risk populations.
Don't Stop ULT
Continue allopurinol/febuxostat during acute flare. Stopping → rebound uric acid fluctuation → worsening flare.
Flare Prophylaxis
Colchicine 0.6 mg daily × 3-6 months when starting or titrating ULT. Prevents mobilization flares from urate crystal dissolution.
Pseudogout
Positively birefringent rhomboid crystals = CPPD (calcium pyrophosphate). Knee most common. Treatment: similar to gout. No ULT equivalent.
📄 One Pager
Rheumatology · One Pager
Gout
Crystal confirmation on aspiration. Acute: colchicine (low-dose) + NSAIDs + steroids. Chronic: treat-to-target uric acid < 6 with allopurinol. Check HLA-B*5801 in at-risk populations.
🧪 Diagnosis
Joint aspiration: negatively birefringent needle-shaped crystals under polarized light. Mono-inflammatory arthritis (1st MTP classic). WBC 2,000-50,000. Culture to rule out concurrent septic joint.
🚨 Acute Flare
Colchicine 1.2 mg → 0.6 mg at 1h → 0.6 BID (low-dose AGREE, 2010). NSAIDs (indomethacin or naproxen). Steroids if both contraindicated. Anakinra (IL-1 blocker) for refractory.
💊 Chronic -ULT
Target uric acid < 6 mg/dL (< 5 if tophi). Allopurinol: start 100 mg, titrate by 100 mg q2-4 weeks. Check HLA-B*5801 (Southeast Asian, African American -SJS/TEN risk). Flare prophylaxis: colchicine 0.6 mg daily × 3-6 months.
💊 Key Drugs
Colchicine1.2 → 0.6 mg (acute)
Allopurinol100-800 mg daily (titrate)
Febuxostat40-80 mg daily (if B*5801+)
Colchicine0.6 mg daily (prophylaxis)
⚠️ Pitfalls
- 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)
RoundsRx · Rheumatology
ACR Gout 2020 · AGREE 2010
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.
🔍 Overview
Organ Involvement & Severity
| Organ | Manifestation | Severity |
|---|---|---|
| Skin / joints | Malar rash, discoid rash, photosensitivity, oral ulcers, arthralgia/arthritis (non-erosive) | Mild -treat with hydroxychloroquine ± NSAIDs |
| Serositis | Pleuritis, pericarditis | Moderate -steroids, NSAIDs, colchicine |
| Hematologic | Autoimmune hemolytic anemia (Coombs+), leukopenia, lymphopenia, thrombocytopenia | Moderate to severe -steroids, IVIG if severe thrombocytopenia |
| Renal (lupus nephritis) | Proteinuria, hematuria, rising Cr, nephrotic/nephritic syndrome. Class IV (diffuse proliferative) is most common and most severe. | Severe -renal biopsy, pulse steroids + mycophenolate or cyclophosphamide |
| CNS (cerebral lupus) | Seizures, psychosis, stroke, transverse myelitis, cognitive dysfunction | Severe -pulse steroids + cyclophosphamide. Rule out other causes (infection, TTP, APS). |
| Pulmonary | Diffuse alveolar hemorrhage (DAH), shrinking lung syndrome, ILD, pulmonary HTN | DAH = life-threatening -pulse steroids + cyclophosphamide + possible plasmapheresis |
Flare Markers
- ↓ C3 / C4 (complement consumed by immune complexes) -most sensitive marker of active disease
- ↑ Anti-dsDNA -correlates with lupus nephritis activity. Rising titers = impending flare.
- ↑ 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 daily CORNERSTONE -reduces flares, organ damage, thrombosis, and mortality. Never stop. Annual eye exam for retinal toxicity. |
| Mild flare (skin, joints) | NSAIDs (short course) + topical steroids. Low-dose prednisone (≤ 7.5 mg/day). |
| Moderate flare (serositis, cytopenias) | Prednisone 0.5–1 mg/kg/day → taper. Add steroid-sparing: mycophenolate, azathioprine, or methotrexate. |
| Severe flare (nephritis Class III/IV, CNS, DAH) | 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).
- C3: 45 (low), C4: 8 (low), anti-dsDNA: 1:640 (elevated) → serologically active.
- Diagnosis: Class III/IV lupus nephritis until biopsy proves otherwise. Renal biopsy is MANDATORY -treatment depends on ISN/RPS class.
- Treatment:
- Mild flare (skin/joints only): Hydroxychloroquine (Plaquenil) 200mg BID (NEVER stop -reduces flares, thrombosis, and mortality). Low-dose prednisone (Deltasone) ≤10mg/day.
- Moderate flare (serositis, cytopenias): Prednisone 0.5-1mg/kg/day, taper over weeks.
- Severe flare (nephritis Class III/IV): Pulse methylprednisolone (Solu-Medrol) 500-1000mg IV × 3 days → prednisone 1mg/kg → taper. Induction: mycophenolate (CellCept) 2-3g/day OR cyclophosphamide (ALMS, 2009 -myco = cyclo for induction). Add belimumab (Benlysta) per BLISS-LN.
- Maintenance: Mycophenolate (CellCept) 1-2g/day + hydroxychloroquine indefinitely.
- 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. (5)
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.
Management:
- Induction: mycophenolate 3g/day + prednisone 0.5-1 mg/kg ALMS, 2009
- Alternative: IV cyclophosphamide Euro-Lupus, 2004
- Continue HCQ (never stop). Consider belimumab BLISS-LN, 2020
- ACEi/ARB for proteinuria and BP
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.
Key findings: CRP 42 (elevated). C3/C4 normal. Anti-dsDNA stable. Procalcitonin 2.4. Urine culture: E. coli.
Management:
- 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.
Key findings: Stable disease. UPCR 0.15. C3/C4 normal. aPL negative.
Management:
- Continue HCQ — safe, reduces neonatal lupus and flares
- Continue azathioprine — safe (unlike mycophenolate, which is teratogenic)
- Anti-Ro/SSA+ → fetal echo at 16 weeks for congenital heart block
- ASA 81 mg at 12 weeks (preeclampsia prophylaxis)
Teaching point: Safe: HCQ, azathioprine, low-dose prednisone. Teratogenic: mycophenolate, cyclophosphamide, MTX. Anti-Ro requires fetal cardiac monitoring.
📣 Sample Presentation
One-Liner
"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 -DIC
| 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
Diagnostic Evaluation -DIC
Workup checklist for DIC: History and physical → targeted labs → imaging as indicated → specialist consultation if needed. Always correlate clinically.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications, relevant PMH
- Physical exam: Focused exam relevant to dic presentation
- Labs: CBC, BMP, relevant disease-specific labs (see Overview tab for specifics)
- Imaging: As clinically indicated based on presentation
- Special studies: Consider disease-specific diagnostics (see Overview tab)
💊 Medications
Key Medications -DIC
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
⚡ Summary
Summary
Diagnosis
EULAR/ACR 2019: ANA positive (entry criterion) + ≥ 10 points from clinical + immunologic domains. High-weighted: class III/IV nephritis, anti-dsDNA, low C3/C4.
Never Stop HCQ
Hydroxychloroquine reduces flares 50-60%, thrombosis, renal damage, and mortality. Continue lifelong. Eye exam annually after 5 years.
Nephritis Biopsy
Biopsy when proteinuria > 500 mg/day, active sediment, or rising Cr. Class determines treatment. Can't predict class clinically.
Treatment by Class
Class I/II: HCQ + monitoring. Class III/IV: induction (mycophenolate or cyclophosphamide + steroids) → maintenance (mycophenolate). Class V: immunosuppression if nephrotic.
Flare Markers
Rising anti-dsDNA + falling C3/C4 + rising CRP (low CRP in SLE suggests flare, not infection). Active urine sediment.
Pregnancy
Plan with rheumatology. HCQ safe (continue). Avoid mycophenolate, cyclophosphamide, MTX (teratogenic). Azathioprine is safe alternative.
📄 One Pager
DIC -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.
DIC -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
EmergentRheumatology
Vasculitis
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.
🔍 Classification by Vessel Size
| Size | Disease | Key Features | Antibody | Treatment |
|---|---|---|---|---|
| Small vessel (ANCA-associated) | GPA (Granulomatosis with Polyangiitis) | Upper airway (sinusitis, saddle-nose, subglottic stenosis) + lungs (cavitary nodules, DAH) + kidneys (RPGN). Classic triad. | c-ANCA / PR3 | Pulse steroids + rituximab or cyclophosphamide RAVE, 2010. Plasmapheresis if severe renal or DAH. |
| MPA (Microscopic Polyangiitis) | Kidneys (RPGN -most common presentation) + lungs (DAH). No upper airway involvement (distinguishes from GPA). No granulomas on biopsy. | p-ANCA / MPO | Same as GPA. | |
| EGPA (Eosinophilic GPA / Churg-Strauss) | Asthma (adult-onset, severe) + eosinophilia (> 1500) + sinusitis + neuropathy (mononeuritis multiplex) + cardiac involvement. | p-ANCA / MPO (40–60%) | 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.
- Cr + GFR -rapidly rising Cr = RPGN
- CXR / CT chest -pulmonary hemorrhage (DAH), nodules/cavities (GPA), infiltrates
- Renal biopsy -pauci-immune crescentic GN (hallmark of ANCA-associated vasculitis). Also classifies severity.
- Tissue biopsy -skin, sural nerve, temporal artery (GCA), lung -shows granulomatous inflammation (GPA) or necrotizing vasculitis
- 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
ANCA Types
c-ANCA/PR3: GPA (granulomatosis with polyangiitis). p-ANCA/MPO: MPA (microscopic polyangiitis) and EGPA (eosinophilic GPA).
Induction
Pulse steroids + rituximab (PR3+/relapsing RAVE, 2010) 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) for all on immunosuppression.
GPA Classic Triad
Upper airway (sinusitis, saddle nose, bloody nasal discharge), lungs (nodules, cavitations, DAH), kidneys (RPGN, RBC casts).
Emergency
Pulmonary-renal syndrome (DAH + RPGN): life-threatening. Pulse steroids + rituximab/cyclophosphamide + PLEX. Don't wait for biopsy to treat.
Monitor Relapse
ANCA titers, Cr, UA with microscopy, CRP q3-6 months. Rising ANCA may precede clinical relapse -consider preemptive treatment.
📄 One Pager
VASCULITIS -AT A GLANCE
🔍 Classify: c-ANCA/PR3 = GPA, p-ANCA/MPO = MPA, eosinophilia = EGPA
🧪 Workup: ANCA, UA, Cr, CRP, CT chest, biopsy
⚡ Induction: Pulse steroids + rituximab (or cyclophosphamide)
🚨 Emergency: DAH/RPGN → treat before biopsy. PLEX if Cr > 5.7.
💊 Maintenance: Rituximab q6 months or azathioprine ≥ 2 years
📈 Monitor: Cr, UA, ANCA, CRP, CBC
🧪 Workup: ANCA, UA, Cr, CRP, CT chest, biopsy
⚡ Induction: Pulse steroids + rituximab (or cyclophosphamide)
🚨 Emergency: DAH/RPGN → treat before biopsy. PLEX if Cr > 5.7.
💊 Maintenance: Rituximab q6 months or azathioprine ≥ 2 years
📈 Monitor: Cr, UA, ANCA, CRP, CBC
📋 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: (1)
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. (3)
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?
Rituximab RAVE, 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 inhibitor ADVOCATE, 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.
Key findings: Classic GPA triad: upper airway (sinusitis) + lower airway (cavitary nodules, hemoptysis) + renal (RPGN with RBC casts). c-ANCA/PR3 positive.
Management:
- 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.
Key findings: EGPA (Churg-Strauss): late-onset asthma + eosinophilia (> 1500) + extra-pulmonary organ involvement (mononeuritis multiplex, skin). Five-Factor Score determines prognosis.
Management:
- Prednisone 1 mg/kg daily (first-line for EGPA)
- If poor prognostic factors (cardiac, GI, renal, CNS involvement): add cyclophosphamide or rituximab
- Mepolizumab 300 mg SQ q4 weeks (anti-IL-5 — FDA-approved for EGPA, steroid-sparing) MIRRA, 2017
- 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).
Monitoring in Hospice
| Parameter | Approach | Notes |
|---|---|---|
| Symptom assessment | Each visit (RN 1-3x/week) | Pain, dyspnea, nausea, anxiety, delirium -use validated scales |
| Functional status | Weekly | 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.
📄 One Pager
Rheumatology · One Pager
ANCA Vasculitis
c-ANCA/PR3 = GPA. p-ANCA/MPO = MPA/EGPA. Induction: steroids + rituximab or cyclophosphamide. PLEX for DAH or Cr > 5.7. Maintenance: rituximab q6 months.
🧪 Types
GPA (granulomatosis with polyangiitis): upper airway + lungs + kidneys. c-ANCA/PR3. MPA (microscopic polyangiitis): kidneys + lungs (no granulomas). p-ANCA/MPO. EGPA: asthma + eosinophilia + vasculitis. p-ANCA/MPO.
🚨 Induction
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)
- Missing pulmonary-renal syndrome (DAH + RPGN = emergent)
- Not starting PCP prophylaxis on immunosuppression
- Missing relapse (monitor ANCA titers, Cr, UA q3-6 months)
RoundsRx · Rheumatology
RAVE 2010 · MAINRITSAN 2014 · PEXIVAS 2020
Rotation
Rheumatology
Autoimmune diseases, vasculitis, crystal arthropathies, and immunosuppression management.
Available Topics
Gout & Pseudogout
SLE Flare
Vasculitis
Rheumatoid Arthritis
Antiphospholipid Syndrome
Scleroderma & Renal Crisis
Septic Arthritis
Palliative Care
Hospice Eligibility Criteria
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. |
| Liver disease | MELD ≥ 30 (not transplant candidate). Refractory ascites. SBP recurrence. HRS. Hepatic encephalopathy despite lactulose/rifaximin. Progressive jaundice. |
| Renal disease | 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. (4)
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. (4)
📣 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.
Monitoring in Hospice
| Parameter | Approach | Notes |
|---|---|---|
| Symptom assessment | Each visit (RN 1-3x/week) | Pain, dyspnea, nausea, anxiety, delirium -use validated scales |
| Functional status | Weekly | 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.
🧪 Workup
Hospice Evaluation
- Functional assessment: PPS (Palliative Performance Scale) or Karnofsky score. PPS ≤ 50% supports hospice eligibility
- 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
- Assess symptom burden: Pain (numeric scale), dyspnea (at rest vs exertion), nausea, anxiety, delirium, constipation
- 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
Eligibility
Prognosis ≤ 6 months if disease runs its usual course. Patient elects comfort. Certified by 2 physicians. Can be revoked if patient improves.
Comfort Meds
Pain: morphine. Dyspnea: morphine + fan. Nausea: ondansetron, haloperidol. Secretions: glycopyrrolate/atropine. Agitation: lorazepam, haloperidol.
Stop Unnecessary
Statins, metformin, vitamins, screening tests, antihypertensives (if comfort-focused). Each med removed = reduced pill burden + side effects.
Hospice ≠ Giving Up
Hospice provides active symptom management, emotional/spiritual support, family bereavement, aide services, equipment, medications.
Prognostic Tools
PPS (Palliative Performance Scale): ≤ 50% supports hospice eligibility. Disease-specific criteria: CHF NYHA IV, COPD FEV₁ < 30%, dementia FAST ≥ 7.
Family Support
Caregiver burnout is real. Hospice provides: respite care (5 days), bereavement counseling × 13 months post-death, 24/7 nurse phone access.
⚡ 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
- Medication reconciliation: Stop all non-comfort medications. Statins, antihypertensives (unless symptomatic), diabetes meds (unless symptomatic hyperglycemia), vitamins, screening labs
- 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
📄 One Pager
Palliative Care · One Pager
Hospice
Prognosis ≤ 6 months. Comfort-focused. Active symptom management + family support. Can be revoked if patient improves. Hospice ≠ giving up.
🧪 Eligibility
Prognosis ≤ 6 months (certified by 2 physicians). Patient elects comfort care. PPS ≤ 50%. Declining functional status, nutritional decline, recurrent hospitalizations. Disease-specific criteria exist.
🚨 Comfort Medications
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)
RoundsRx · Palliative Care
NHPCO Guidelines · CMS Hospice Conditions
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
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., 2018 For methadone conversions: ALWAYS consult pharmacy or palliative care -methadone conversion is non-linear and complex. CDC Opioid Prescribing 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). |
| Bone metastases | Dexamethasone (Decadron) 4–8 mg daily + radiation therapy (single fraction effective) + NSAIDs if tolerated | Steroids reduce peri-tumor edema → rapid pain relief. Bisphosphonates/denosumab for skeletal events prevention. |
| Bowel obstruction | 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%. 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), (3)
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. (3)
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. (2)
📣 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.
💊 Medications
Equianalgesic Conversion Table
| Opioid | PO Dose (equianalgesic) | IV Dose | PO:IV Ratio | Notes |
|---|---|---|---|---|
| Morphine (MS Contin) | 30 mg | 10 mg | 3:1 | Reference standard. Avoid in CKD (M6G accumulates). IR: q4h. ER: q8–12h. |
| Hydromorphone (Dilaudid) | 6 mg | 1.5 mg | 4–5:1 | 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. |
| 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. Consult 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
Why Rotate
Tolerance, intolerable side effects (nausea, myoclonus, pruritus), renal failure (morphine metabolites accumulate), poor pain control.
Equianalgesic
Oral morphine 30 = oxycodone 20 = hydromorphone 6. IV morphine 10 = hydromorphone 1.5. Always apply 25-50% reduction for incomplete cross-tolerance.
Methadone Danger
Non-linear conversion. Long half-life (15-60h). QTc prolongation. Use dedicated methadone tables. Start low, titrate over days. Experienced prescribers only.
Fentanyl Patch
For stable opioid requirements only (not acute pain). Calculate 24h oral morphine equivalent → divide by 2 (approximately) = mcg/hr fentanyl.
Cross-Tolerance
Previous opioid exposure means partial tolerance -but cross-tolerance is INCOMPLETE between different opioids. Always reduce calculated dose by 25-50%.
Monitor After Rotation
Closely monitor × 48-72h after rotation. New opioid may be more or less potent than expected. Adjust based on pain scores and breakthrough use.
📄 One Pager
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.
📊 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.
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. |
| Terminal secretions ("death rattle") | Glycopyrrolate 0.2–0.4 mg IV/SC q4h or atropine drops 1% SL q4h | 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. |
| Terminal agitation / delirium | Haloperidol (Haldol) 1–2 mg IV/SC q4h. Add lorazepam 1–2 mg if refractory. | 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
- Nausea: Ondansetron, haloperidol, metoclopramide
- Delirium: Haloperidol 0.5-2mg. Treat reversible causes.
- GOC: REMAP framework
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Morphine | 2-5mg PO/SL q2-4h | PO/SL | Pain + dyspnea |
| Gabapentin | 100-900mg TID | PO | Neuropathic pain |
| Dexamethasone | 4-8mg daily | PO/IV | Bone mets, edema, obstruction |
| Haloperidol | 0.5-2mg q4-6h | PO/IV | Nausea + delirium |
| Glycopyrrolate | 0.2mg SL q4h | SL | Secretions |
| Lorazepam | 0.5-1mg SL q4h | SL | Anxiety, agitation |
📋 On Rounds
Pimp Questions
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. (5)
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. (3)
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
REMAP
Reframe → Expect emotion → Map values → Align → Plan. The gold standard framework for goals of care conversations.
Code Status ≠ GOC
Goals of care is about values and what matters. Code status is one small part. Don't lead with "do you want CPR?" -map values first.
Dyspnea
Morphine (first-line), fan at face, O₂ for hypoxic patients, benzodiazepines for anxiety component. Positioning. Discontinue SpO₂ alarms in comfort care.
Pain
WHO ladder: non-opioid → weak opioid → strong opioid. Adjuvants for neuropathic: gabapentin, duloxetine. Dexamethasone for bone pain, bowel obstruction, cerebral edema.
Prognostication
PPS, ECOG, disease-specific models. Clinicians overestimate survival by 3-5×. Use objective tools. Communicate uncertainty honestly.
When to Consult
Refractory symptoms, complex goals of care, family conflict, transition to hospice, existential/spiritual distress, withdrawal of life-sustaining treatment.
📄 One Pager
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.
💊 Key Drugs
Morphine2-5 mg PO/SL q2-4h PRN (dyspnea + pain)
Gabapentin100-900 mg TID (neuropathic)
Dexamethasone4-8 mg daily (brain mets, obstruction)
Haloperidol0.5-2 mg q4-6h (nausea/delirium)
⚠️ Pitfalls
- Jumping to code status without mapping values first
- Withholding morphine for dyspnea (effective and safe at appropriate doses)
- Not considering palliative care consult until patient is dying
- O₂ for non-hypoxic dyspnea (fan at face is equally effective Fan for Dyspnea Trial, 2010)
RoundsRx · Palliative Care
REMAP Framework · Abernethy BMJ 2003 + 2010
Rotation
Palliative Care
Symptom management, goals of care conversations, pain at end of life, hospice criteria, and comfort-focused care.
Available Topics
Goals of Care & Symptom Management
Hospice Eligibility Criteria
Opioid Rotation & Pain
Code Status & Advance Directives
Family Meeting Framework
Prognostication Tools
Non-Opioid Symptom Management
Palliative Extubation
📋 Major Guidelines
Ambulatory
Outpatient Diabetes Management
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
Step 1 -All Type 2 DM
- Metformin (Glucophage) remains first-line for most patients (A1c reduction ~1.5%, weight neutral, cheap, CV benefit UKPDS, 1998)
- Lifestyle: 150 min/week moderate exercise, 5–7% weight loss target, medical nutrition therapy DPP, 2002
- A1c target: < 7% for most (correlates with TIR >70%). < 6.5% if early disease, no hypoglycemia risk. < 8% if elderly, multiple comorbidities, limited life expectancy. 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)
| Comorbidity | Preferred Agent | Key Trial | Notes |
|---|---|---|---|
| ASCVD or high CV risk | GLP-1 RA (semaglutide, liraglutide, dulaglutide) PREFERRED | SUSTAIN-6, 2016 LEADER, 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, 2015 DAPA-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, 2020 EMPA-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, 2021 SURMOUNT, 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. |
| Cost / simplicity priority | Sulfonylurea (glipizide, glimepiride) or pioglitazone | - | Very cheap. SU: hypoglycemia + weight gain risk. Pioglitazone: fluid retention (avoid in HF), fracture risk, 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)
• 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. (5)
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, 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.
📋 Case 2 — T2DM with CKD and HF: SGLT2 Inhibitor
Patient: 58F with T2DM (A1c 7.8%), HFrEF (EF 35%), eGFR 38, UACR 380 mg/g. On metformin 500 BID, lisinopril, carvedilol, spironolactone. BMI 28.
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.
Management:
- Add dapagliflozin 10 mg daily (or empagliflozin 10 mg) DAPA-CKD, 2020
- 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)
- DSME referral (diabetes self-management education), nutrition counseling
- 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."
Key Points to Cover on Rounds
A1c 8.6 (goal <7). BMI 34. ASCVD + CKD -drug selection driven by comorbidities, not just A1c. Changes: (1) Add semaglutide 0.25 mg SQ weekly, uptitrate to 1 mg (GLP-1 RA -proven CV benefit [SUSTAIN-6], weight loss, renal protection), (2) Add empagliflozin 10 mg daily (SGLT2i -proven CV + renal benefit [EMPA-REG, CREDENCE], even at eGFR 52), (3) Continue metformin 1000 BID. Screening: eye exam (overdue), foot exam done today (monofilament intact), UACR 180 (albuminuria -SGLT2i indicated). Statin confirmed (atorvastatin 80). Plan: recheck A1c in 3 months, titrate semaglutide, UACR in 6 months.
Monitoring -Goals of Care & Symptom Management
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Goals of Care & Symptom Management
Workup for Goals of Care & Symptom Management: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
⚡ Management
Management -Goals of Care & Symptom Management
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
💊 Medications
Medications -Goals of Care & Symptom Management
Medication details for Goals of Care & Symptom Management are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Drug Selection
ASCVD → GLP-1 RA first [SUSTAIN-6, LEADER]. CKD → SGLT2i [CREDENCE, DAPA-CKD]. HF → SGLT2i [DAPA-HF]. Obesity → GLP-1 RA. Continue metformin in most.
A1c Targets
< 7% for most. < 6.5% for newly diagnosed, young, no complications. < 8% for elderly, limited life expectancy, hypoglycemia risk, long-standing disease [ACCORD lesson].
Screening
Eye exam annually. Foot exam annually (monofilament). UACR annually if ≥ 5 years T1DM or at diagnosis T2DM. Lipid panel. BP every visit.
SGLT2i Caveats
Monitor for euglycemic DKA (especially in T1DM, surgery, fasting). Mycotic genital infections. AKI risk with dehydration. Avoid if eGFR < 20.
GLP-1 RA Caveats
GI side effects (titrate slowly). Pancreatitis risk (debated). Thyroid C-cell tumors (rodent data). Contraindicated in MEN2 or medullary thyroid cancer.
Legacy Effect
Early intensive control has lasting benefits decades later [UKPDS post-trial, DCCT/EDIC]. Treat early and aggressively. Relax targets as disease advances.
📄 One Pager
One Pager -Goals of Care & Symptom Management
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
GOALS OF CARE & SYMPTOM MANAGEMENT -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
Ambulatory
Obesity Management & GLP-1 Agents
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.
💊 Anti-Obesity Medications
| Drug | Mechanism | Weight Loss | Key Notes |
|---|---|---|---|
| Semaglutide 2.4 mg (Wegovy) PREFERRED | GLP-1 receptor agonist → ↑ satiety, ↓ appetite, delayed gastric emptying | ~15% body weight STEP 1, 2021 | 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 weight SURMOUNT-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. |
| Phentermine-topiramate ER (Qsymia) | Sympathomimetic + anticonvulsant (appetite suppression) | ~8–10% | Oral daily. Avoid in uncontrolled HTN, glaucoma, hyperthyroidism. Topiramate: teratogenic (REMS program), cognitive effects, metabolic acidosis, kidney stones. |
| Naltrexone-bupropion (Contrave) | Opioid antagonist + dopamine/NE reuptake inhibitor | ~5–6% | 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.
- Roux-en-Y gastric bypass: ~30% excess weight loss. DM remission in 60–80%. Malabsorptive → lifelong vitamin supplementation (B12, iron, calcium, folate, vitamin D).
- 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 → (1)
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. (2)
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
- Alternative: sleeve gastrectomy (20-25% weight loss, lower complication rate, simpler technically)
- Pre-op requirements: OSA screening, cardiac clearance, nutritional labs (B12, iron, folate, vitamin D), psych evaluation
- Lifelong supplementation post-RYGB: B12, iron, calcium + vitamin D, multivitamin (malabsorptive anatomy)
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
- Continue metformin (complementary mechanism, renal protection)
- 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]), (2) tirzepatide (dual GIP/GLP-1, ~20% weight loss [SURMOUNT-1]). 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.
Monitoring Parameters -HIT (Heparin-Induced Thrombocytopenia)
| 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 -Outpatient Diabetes Management
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Diagnostic Evaluation -HIT (Heparin-Induced Thrombocytopenia)
Workup checklist for HIT (Heparin-Induced Thrombocytopenia): History and physical → targeted labs → imaging as indicated → specialist consultation if needed. Always correlate clinically.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications, relevant PMH
- Physical exam: Focused exam relevant to hit (heparin-induced thrombocytopenia) presentation
- Labs: CBC, BMP, relevant disease-specific labs (see Overview tab for specifics)
- Imaging: As clinically indicated based on presentation
- Special studies: Consider disease-specific diagnostics (see Overview tab)
💊 Medications
Key Medications -HIT (Heparin-Induced Thrombocytopenia)
Refer to the Management tab for the full treatment algorithm with drug choices, dosing, and contraindications. Refer to the Antibiotic Guide if infectious etiology. Always check renal dosing and drug interactions.
- First-line agents: See Management tab for evidence-based recommendations with trial citations
- Renal adjustment: Check CrCl -see Antibiotic Guide renal dosing tab or Calculators for CrCl
- Drug interactions: See Drug Interactions reference
- Allergies: Always verify before prescribing. Document reaction type (rash vs anaphylaxis)
⚡ Summary
Summary
Pharmacotherapy
Semaglutide 2.4 mg SQ weekly (~15% weight loss [STEP 1]). Tirzepatide (~20% [SURMOUNT-1]). Titrate slowly to reduce GI side effects.
Bariatric Surgery
BMI ≥ 40 or ≥ 35 + comorbidity. Sleeve gastrectomy most common. RYGB gold standard. T2DM remission 60-80%. 50-70% excess weight loss.
Lifestyle
Foundation: 150 min/week moderate exercise + caloric deficit + behavioral counseling. Alone = ~5% weight loss. Needed alongside all pharmacotherapy.
Comorbidity Screening
OSA (STOP-BANG), NAFLD (LFTs, US), T2DM (A1c), dyslipidemia, HTN, GERD, OA, depression. Treat all identified comorbidities.
Post-Bariatric
Lifelong vitamin monitoring (B12, iron, calcium, D, folate). Protein ≥ 60g/day. No NSAIDs (marginal ulcer). Psychiatric support.
Not "Willpower"
Obesity is a chronic disease with genetic, hormonal, and environmental drivers. Frame treatment like any chronic disease -no blame, evidence-based management.
📄 One Pager
HIT (Heparin-Induced Thrombocytopenia) -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.
HIT (HEPARIN-INDUCED THROMBOCYTOPENIA) -AT A GLANCE
📋 Diagnose: See Overview tab for criteria
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🧪 Workup: Focused labs + imaging → see Workup tab
⚡ Treat: Evidence-based algorithm → see Management tab
💊 Drugs: Key medications with dosing → see Medications tab
📈 Monitor: Disease-specific targets → see Monitoring tab
📣 Present: One-liner + key points → see Rounds tab
🔍 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.
⚡ Management
Management -Obesity Management & GLP-1 Agents
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
📄 One Pager
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]). Tirzepatide (dual GIP/GLP-1, ~20% [SURMOUNT-1]). Titrate slowly to minimize GI side effects. Lifestyle (150 min/week exercise + dietary changes) is always the foundation.
💊 Bariatric Surgery
BMI ≥ 40 or ≥ 35 + comorbidity. Sleeve gastrectomy (most common). RYGB (gold standard). T2DM remission 60-80%. 50-70% excess weight loss. Lifelong vitamin monitoring required.
💊 Key Drugs
Semaglutide0.25 → 2.4 mg SQ weekly
Tirzepatide2.5 → 15 mg SQ weekly
Phentermine-topiramate3.75/23 → 15/92 mg daily
Lifestyle150 min/week exercise + caloric deficit
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 events EAGLES, 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. |
| NRT -patch | 21 mg/day × 6 wks → 14 mg × 2 wks → 7 mg × 2 wks (if > 10 cig/day). 14 mg start if < 10/day. | ~15–20% alone, ~25–30% combined | 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: (1)
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). (2)
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. (3)
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.
Management:
- Behavioral counseling FIRST — pregnancy-specific counseling programs achieve 5-10% quit rates (doubles with intensive support)
- 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.
Monitoring -Outpatient Diabetes Management
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🔍 Overview
Overview -Outpatient Diabetes Management
See the tabs above for the complete clinical reference: Workup, Management, Medications, Monitoring, Rounds, Summary, and One Pager.
🧪 Workup
Workup -Outpatient Diabetes Management
Workup for Outpatient Diabetes Management: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
⚡ Management
Management -Outpatient Diabetes Management
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
💊 Medications
Medications -Outpatient Diabetes Management
Medication details for Outpatient Diabetes Management are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Most Effective
Varenicline + NRT patch = highest quit rate (~35-40%). Start varenicline 1 week pre-quit date. NRT patch on quit date. Continue × 12 weeks.
Varenicline
0.5 mg daily × 3 days → 0.5 BID × 4 days → 1 mg BID. Safe in psychiatric patients EAGLES, 2016. FDA removed black box warning.
NRT Options
Patch (21/14/7 mg taper), gum, lozenge, inhaler, nasal spray. Patch for baseline + short-acting form for breakthrough cravings.
Bupropion
150 mg daily × 3 days → 150 BID. Start 1-2 weeks pre-quit. Also treats depression. Avoid in seizure history, eating disorders.
Lung Cancer Screening
Age 50-80 + ≥ 20 pack-years + current smoker or quit within 15 years → annual LDCT [USPSTF 2021]. Reduces mortality 20% [NLST].
Brief Intervention
5 A's: Ask (smoking status), Advise (quit), Assess (readiness), Assist (pharmacotherapy + counseling), Arrange (follow-up). Takes 3 minutes.
📄 One Pager
One Pager -Outpatient Diabetes Management
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
OUTPATIENT DIABETES MANAGEMENT -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
Ambulatory
Preventive Care & Screening
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. | NLST, 2011: 20% mortality reduction. NELSON, 2020: confirmed. Shared decision-making required. |
| Prostate | PSA | 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. |
| 2. LDL ≥ 190 | High-intensity statin. Likely familial hypercholesterolemia. Lipid specialist referral. |
| 3. DM age 40–75, LDL 70–189 | Moderate-intensity statin (atorvastatin 10–20 mg, rosuvastatin 5–10 mg). High-intensity if 10-year ASCVD risk ≥ 7.5%. |
| 4. Non-DM, LDL 70–189, 10-yr ASCVD ≥ 7.5% | Moderate to high-intensity statin. If borderline (5–7.5%) → consider risk enhancers (family hx, CAC score, CRP, ABI). |
Hypertension (ACC/AHA 2017)
- Stage 1 HTN: 130–139/80–89. Lifestyle × 3–6 months first if ASCVD risk < 10%. Start medication if ≥ 10% risk or if not at goal after lifestyle.
- Stage 2 HTN: ≥ 140/90. Start 2-drug combination therapy. Reassess in 1 month.
- Target: < 130/80 for most adults SPRINT, 2015.
- 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
- CV risk: ASCVD calculator, lipids, BP
- Metabolic: A1c q3y if ≥35 + overweight
- Depression: PHQ-2 annually
- Hep C: one-time 18-79
- HIV: at least once 15-65
- Osteoporosis: DEXA 65F/70M
🚨 Management
Management
- Statin: moderate 7.5-20% risk, high-intensity ≥20%
- ASA: limited -40-59yo if ≥10% risk, shared decision
- BP <130/80 [SPRINT]
- Smoking: 5 A's + varenicline+NRT
- Vaccines: flu, COVID, Tdap, shingrix≥50, PCV20≥65, HPV≤26
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Atorvastatin (Lipitor) | 40-80mg | PO | High-intensity statin |
| Varenicline | 1mg BID × 12wk | PO | Smoking cessation |
| ASA 81mg | Daily | PO | 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
Breast: mammogram q2y 40-74. Cervical: Pap/HPV 21-65. Colon: start at 45 (colonoscopy q10y or FIT annual). Lung: LDCT 50-80 if ≥ 20 pack-years.
CV Risk
10-year ASCVD risk calculator. Statin: moderate if 7.5-20%, high-intensity if ≥ 20% or known ASCVD. ASA: limited role (USPSTF: ages 40-59 if ≥ 10% risk, shared decision).
Immunizations
Flu (annual), COVID (per current guidance), Tdap/Td (q10y), shingrix (≥ 50), PCV20 (≥ 65), HPV (through age 26, catch-up to 45).
Depression Screening
PHQ-2 then PHQ-9 annually in primary care. Universal screening recommended by USPSTF.
Diabetes Screening
Fasting glucose, A1c, or OGTT. Screen every 3 years age 35-70 if overweight/obese. Screen earlier if risk factors (FH, ethnicity, GDM history).
Osteoporosis
DEXA at age 65 (women), 70 (men). Earlier if risk factors (steroids, low BMI, FH hip fracture). Treat: bisphosphonates first-line.
RoundsRx Licensed Content - Unauthorized Use Prohibited📄 One Pager
Primary Care · One Pager
Preventive Care
Mammogram q2y 40-74. Pap/HPV 21-65. Colonoscopy at 45. LDCT 50-80 if ≥ 20 pack-years. ASCVD risk → statin threshold. PHQ-2 depression screen annually.
🧪 Cancer Screening
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].
💊 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)
RoundsRx · Primary Care
USPSTF Recommendations 2021-2024 · ACC/AHA ASCVD Guidelines
Rotation
Ambulatory / Outpatient
Continuity clinic essentials -preventive care, chronic disease management, screening guidelines, and outpatient prescribing.
Available Topics
Preventive Care & Screening
Outpatient Diabetes
Obesity & GLP-1 Agents
Smoking Cessation
Trauma Primary & Secondary Survey
Acute Abdomen
Superior Vena Cava Syndrome
Septic Arthritis
Code Status & Advance Directives
Family Meeting Framework
Tuberculosis
Fungal Infections
Nephrotic vs Nephritic Syndrome
Renal Tubular Acidosis
PMR & Giant Cell Arteritis
Hypoparathyroidism
Burns Management
Hypothermia & Drowning
Hyperviscosity Syndrome
Dermatomyositis & Polymyositis
Prognostication Tools
Contrast-Induced Nephropathy
Diabetic Foot Infection
📋 Major Guidelines
Quick Reference
Antibiotic Guide
Empiric coverage by infection site, spectrum of activity, and renal dose adjustments. This is your go-to for every antibiotic decision on the wards.
🎯 Empiric Antibiotics by Condition
🫁 Pneumonia (CAP / HAP / VAP)
5 regimens
›
| Setting | First-Line | Alternatives / Severe | Duration |
|---|---|---|---|
| CAP -outpatient, healthy | Amoxicillin (Amoxil) 1g TID | Doxycycline 100 mg BID if penicillin allergy | 5 days |
| CAP -outpatient, comorbidities | Augmentin 875 BID + azithromycin | Respiratory FQ monotherapy (levofloxacin 750 mg daily) | 5 days |
| CAP -inpatient (non-ICU) | Ceftriaxone (Rocephin) 1–2g IV + azithro 500 IV | Add vancomycin if MRSA risk | 5 days (if stable ×48h) Short-Course CAP Trial, 2016 |
| CAP -ICU (severe) | Ceftriaxone (Rocephin) 2g IV + azithro 500 IV | + 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, 2024). Need cefepime + anaerobes → add metronidazole. | 7 days ATS/IDSA, 2016 |
🔬 Urinary Tract Infections
3 regimens
›
| Setting | First-Line | Alternatives | Duration |
|---|---|---|---|
| Uncomplicated cystitis | Nitrofurantoin (Macrobid) 100 mg BID | TMP-SMX DS BID × 3d. Fosfomycin 3g × 1. Avoid FQ for cystitis. | 3–5 days |
| Pyelonephritis -outpatient | Ciprofloxacin (Cipro) 500 BID | Ceftriaxone 1g IM × 1 + oral step-down | 5–7 days |
| Pyelonephritis -inpatient | Ceftriaxone (Rocephin) 1g IV daily | Pip-tazo or meropenem if ESBL/MDR risk | FQ 5–7d, TMP-SMX 7–10d, beta-lactam 10–14d (total duration depends on PO step-down agent) |
ASB (asymptomatic bacteriuria) = do NOT treat -except in pregnancy and pre-urologic procedure. Nitrofurantoin: avoid if CrCl < 30.
🩹 Skin & Soft Tissue Infections
2 regimens
›
| Type | First-Line | Alternatives | Duration |
|---|---|---|---|
| Cellulitis (non-purulent) | Cefazolin (Ancef) 2g IV q8h (inpatient) or cephalexin (Keflex) 500 QID (outpatient) | Purulent/abscess → I&D + TMP-SMX or doxycycline for MRSA | 5–7 days |
| Necrotizing fasciitis SURGICAL EMERGENCY | Vanc + pip-tazo + clindamycin | Clindamycin inhibits toxin production (Group A strep). EMERGENT surgical debridement. | Until source controlled |
🫃 Intra-Abdominal Infections
2 regimens
›
| Setting | First-Line | Alternatives | Duration |
|---|---|---|---|
| Community intra-abdominal | Ceftriaxone (Rocephin) 2g + metronidazole (Flagyl) 500 q8h | 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 dose European 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 BID PREFERRED | 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
| 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. Check troughs. Nephrotoxic -avoid with pip-tazo if possible ACORN, 2024. |
| 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. |
| Meropenem (Merrem) | 1g IV q8h | 500 mg IV q12h | 500 mg IV q12h + dose after HD | Lower seizure threshold than imipenem. |
| Levofloxacin (Levaquin) | 750 mg IV/PO daily | 750 mg q48h | 500 mg q48h | Not removed by HD. Avoid in myasthenia. |
| TMP-SMX (Bactrim) | DS BID (UTI) or 15 mg/kg/day (PCP) | Half dose if CrCl 15–30. Avoid <15. | Dose after HD | Causes hyperkalemia (blocks ENaC). Falsely ↑ Cr (blocks tubular secretion). |
| Nitrofurantoin (Macrobid) | 100 mg BID | AVOID if CrCl < 30 | 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 may increase AKI compared to vanc + cefepime ACORN, 2024. 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.
| Feature | Vancomycin | Linezolid (Zyvox) |
|---|---|---|
| MOA | Cell wall synthesis inhibitor -binds D-Ala-D-Ala terminus of peptidoglycan precursors, preventing cross-linking. Bactericidal (slowly). | 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) | IV and PO -100% oral bioavailability (PO = IV) |
| MRSA | ✓ Gold standard | ✓ Equivalent |
| VRE* *= Vancomycin-Resistant Enterococcus | ✗ No | ✓ Yes -one of very few VRE options |
| Lung penetration | Poor (~25%) | Excellent (~100%) |
| CSF penetration | Moderate (needs inflamed meninges) | Good |
| Renal dosing | YES -must adjust. AUC/MIC-guided dosing (target 400-600). | No renal adjustment. No drug levels needed. |
| Key toxicity | Nephrotoxicity, Red Man Syndrome (infuse over ≥1h), ototoxicity, DRESS (rare) | Thrombocytopenia (#1 -dose-dependent, usually > 14 days), serotonin syndrome (MAOi activity), lactic acidosis (mitochondrial toxicity), peripheral neuropathy (may be irreversible), optic neuritis (vision loss -check visual acuity if > 28 days), myelosuppression (anemia, leukopenia) |
| Duration limit | No hard limit | ≤ 14 days preferred. > 14d: ↑ thrombocytopenia. > 28d: ↑↑ neuropathy, optic neuritis, lactic acidosis. If > 2 weeks needed → monitor closely or switch to vanc. |
| Monitoring | Trough AUC/MIC 400–600, BMP, CBC | CBC twice weekly (platelets). If > 14d: weekly lactate, visual acuity, neuro exam for neuropathy symptoms (numbness, tingling). No drug levels needed. |
| Drug interactions | Nephrotoxics (aminoglycosides, pip-tazo) | SSRIs, SNRIs, MAOIs, tramadol, meperidine → serotonin syndrome |
| Cost | Cheap | Expensive |
🏆 Choose Vancomycin
- MRSA bacteremia -bactericidal, proven outcomes
- Endocarditis -need bactericidal activity
- Osteomyelitis -long-duration therapy OK
- Empiric broad MRSA coverage -default first-line
- Cost-sensitive settings
🏆 Choose Linezolid
- 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.
• > 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 | 5 days | If afebrile ≥48h + ≤1 sign instability (HR, RR, BP, SpO₂, mental status) |
| CAP (complicated)* *= Empyema, lung abscess, necrotizing pneumonia, cavitation, or inadequate clinical response by day 3–5 | 2–6 weeks | Depends on drainage adequacy and imaging resolution. Empyema needs chest tube + abx |
| HAP* / VAP* *HAP = Hospital-Acquired Pneumonia (≥48h after admission) *VAP = Ventilator-Associated Pneumonia (≥48h after intubation) | 7 days | ATS/IDSA 2016. Shorter courses reduce resistance |
| COPD exacerbation (with abx) | 5 days | Only if ≥2 Anthonisen criteria |
| Lung abscess | 4–6 weeks | Until imaging improvement |
Urinary
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Simple cystitis (women) | 3–5 days | Nitrofurantoin (Macrobid) 5d, TMP-SMX (Bactrim) 3d, fosfomycin 1 dose |
| 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 |
| Complicated gram-negative bacteremia = Undrainable source, endovascular, prosthetic material, immunocompromised, persistent bacteremia >72h, or metastatic infection | 14 days | Any ONE feature makes it complicated → 14 days |
| Staph aureus bacteremia (MSSA*/MRSA*) *MSSA = Methicillin-Sensitive Staph aureus *MRSA = Methicillin-Resistant Staph aureus | ≥4 weeks (minimum) | ALWAYS. TTE/TEE required. ID consult mandatory |
| Coag-negative staph (true infection) | 5–7 days + line removal | Often contaminant -need 2+ positive cultures |
| Enterococcal bacteremia | 7–14 days | Longer if endocarditis not excluded |
| Candidemia | 14 days from first negative culture | Ophthalmology consult. Remove all central lines. Echo |
S. aureus bacteremia is NEVER uncomplicated enough for short-course therapy. Minimum 4 weeks IV. Always echo. Always ID consult.
Skin / Soft Tissue
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Simple cellulitis | 5 days | Extend to 7–10d if slow response |
| Purulent SSTI* / abscess *SSTI = Skin and Soft Tissue Infection | I&D* ± 5–7 days *I&D = Incision and Drainage | I&D is primary treatment |
| Necrotizing fasciitis | Until debridement complete | Surgical emergency |
| Diabetic foot (soft tissue) | 1–2 weeks | If no osteomyelitis |
| Diabetic foot (osteo) | 6 weeks | Based on bone culture |
Intra-abdominal
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Intra-abdominal (adequate source control) | 4 days | STOP-IT, 2015. NOT 7–14 days |
| Cholangitis / cholecystitis | Source control + 4–5 days | Cholecystectomy within 72h |
| SBP* *= Spontaneous Bacterial Peritonitis | 5 days | Ceftriaxone. Albumin day 1 and 3 |
| C. difficile (initial) | 10 days | Fidaxomicin preferred |
| C. difficile (fulminant) | Until improving | PO vanc 500mg q6h + IV metronidazole |
Bone / Joint
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Osteomyelitis (native bone) | 6 weeks | IV → PO step-down OK (OVIVA trial) |
| Prosthetic joint (DAIR*) *DAIR = Debridement, Antibiotics, Implant Retention | 6 wk IV + chronic suppression | Rifampin backbone if staph |
| Septic arthritis (native) | 3–4 weeks | GPC* 3wk, GNR* 4wk. I&D essential *GPC = Gram-Positive Cocci (staph, strep, enterococcus) *GNR = Gram-Negative Rods (E. coli, Klebsiella, Pseudomonas) |
CNS
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Bacterial meningitis | 7–21 days | Meningo 7d, pneumo 10–14d, Listeria 21d, GNR 21d |
| Brain abscess | 6–8 weeks | Often need surgical drainage |
| Epidural abscess | 6–8 weeks | Surgical drainage + IV abx |
Endocarditis
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| Native valve (strep) | 4 weeks | 2wk if uncomplicated + gent synergy |
| Native valve (staph) | 6 weeks | Nafcillin for MSSA, vanc for MRSA |
| Prosthetic valve | ≥6 weeks | Rifampin + gentamicin backbone |
Other
| Infection | Duration | Key Notes / Evidence |
|---|---|---|
| TB (standard) | 6 months | 2 months RIPE* → 4 months RI *RIPE = Rifampin, Isoniazid, Pyrazinamide, Ethambutol |
| TB (meningitis / bone) | 9–12 months | Extended duration |
| Febrile neutropenia | Until afebrile + ANC* ≥500 × 2d *ANC = Absolute Neutrophil Count | Min 7 days if documented infection |
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. ↑ SVR + mild inotropy. SSC, 2021 | - |
| 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. |
| Milrinone (Primacor) INOTROPE | 0.125–0.75 mcg/kg/min | PDE3 inhibitor | Inodilator. RV failure, pulmonary HTN, post-cardiac surgery. Inotropy + ↓ PVR. | Hypotension (vasodilation). Renally cleared -dose-adjust in AKI. |
| Angiotensin II (Giapreza) LAST RESORT | 20–200 ng/kg/min | AT1 receptor | Catecholamine-refractory vasodilatory shock. ATHOS-3, 2017 | Thrombosis risk. Very expensive. Last-line agent. |
| Dopamine (Intropin) AVOID | 2–20 mcg/kg/min | D1, β₁, α₁ (dose-dependent) | 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 on NE ≥ 0.25 mcg/kg/min for ≥ 4h | 200 mg/day IV (50 mg q6h or continuous infusion) | ADRENAL, 2018: faster shock reversal, no mortality benefit. APROCCHSS, 2018: mortality benefit in most severe subgroup. |
| Methylene blue (ProvayBlue) | Vasoplegia (post-cardiac surgery, refractory distributive shock) | 1–2 mg/kg IV bolus, may repeat or infuse 0.5 mg/kg/hr | Case series. Inhibits NO synthase → restores SVR. Rescue agent. |
| Thiamine (Vitamin B1) | Suspected deficiency (alcoholism, malnutrition, refeeding) | 200–500 mg IV q8h × 3 days | 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 NE ≥ 0.25 for ≥ 4h. SSC, 2021
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: higher mortality + more arrhythmias vs NE. 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: NE had lower mortality + fewer arrhythmias |
| 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 |
Quick Reference
Insulin Guide
Insulin types, inpatient basal-bolus dosing, correction scales, DKA drip protocol, and hypoglycemia management.
🧮
Insulin Calculator
Sliding Scale → Basal-Bolus converter & weight-based dosing. Click to jump ↓
Insulin Types Overview
| Type | Name | Onset | Peak | Duration | Key Notes |
|---|---|---|---|---|---|
| Rapid-Acting | Lispro (Humalog), Aspart (NovoLog), Glulisine (Apidra) | 15 min | 1–2 h | 3–5 h | 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.
🟢 Low-Dose Scale
Use for insulin-sensitive patients:
- Elderly (≥ 70 yr) -reduced counter-regulatory response, higher hypo risk
- CKD (GFR < 30) -reduced insulin clearance, insulin lasts longer
- Hepatic impairment -decreased gluconeogenesis + insulin metabolism
- Malnourished / low BMI (< 18.5) -low glycogen stores
- Type 1 DM (lean) -insulin-sensitive, high DKA risk
- Adrenal insufficiency -impaired counter-regulation
- NPO > 24h -depleted glycogen, no oral intake to buffer
- TDD < 30 units/day
⚠ These patients crash fast. Always have D50 at bedside. BG checks q4–6h minimum.
🔵 Medium-Dose Scale
Use for most hospitalized patients:
- Type 2 DM on oral agents -moderate insulin resistance
- New diabetes diagnosis -unknown sensitivity, start moderate
- Normal BMI (18.5–30) with diabetes
- A1c 7–9% -moderately uncontrolled
- Post-surgical patients -stress hyperglycemia but no steroids
- TDD 30–80 units/day
Default starting scale. Reassess in 24–48h. Upgrade to high if BG consistently > 250.
🔴 High-Dose Scale
Use for insulin-resistant patients:
- ON STEROIDS -#1 indication for high-dose scale. Steroids cause severe insulin resistance
- Obese (BMI > 35) -increased insulin resistance
- TDD > 80 units/day -already requiring large insulin doses
- A1c > 10% -severely uncontrolled, likely very resistant
- TPN / tube feeds -continuous glucose load
- Sepsis / critical illness -stress hormones ↑ insulin resistance
- Cushing's syndrome -endogenous cortisol excess
- Transplant patients on tacrolimus -tacrolimus causes insulin resistance + beta cell toxicity
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.
🚀 Launch Code Clock →
Cardiac Arrest -Adult Algorithm
Start CPR immediately. Rhythm check every 2 minutes. Push hard (≥ 2 inches), push fast (100–120/min), full recoil, minimize interruptions (< 10 sec for rhythm checks).
⚡ Shockable: VF / pVT
Shock
Defibrillate: biphasic 120–200J (or per device). Monophasic 360J. Resume CPR immediately × 2 min.
2 min
Rhythm check. If still VF/pVT → shock again. Resume CPR. Give epinephrine 1 mg IV/IO q3–5 min.
4 min
Rhythm check. If still VF/pVT → shock + amiodarone 300 mg IV/IO bolus. (2nd dose: 150 mg).
Ongoing
Continue 2-min cycles: CPR → rhythm check → shock if VF/pVT → epi q3–5 min. Search for reversible cause (H's & T's).
🔇 Non-Shockable: PEA / Asystole
Immediately
CPR + epinephrine 1 mg IV/IO as soon as access obtained. No shock for PEA/asystole.
2 min
Rhythm check. If PEA/asystole → resume CPR. Epi 1 mg q3–5 min.
Key
Find and treat the cause. PEA has a cause -run through H's & T's aggressively. Asystole is usually a terminal rhythm.
Transition
If rhythm changes to VF/pVT → switch to shockable pathway immediately.
ACLS Drug Dosing
| Drug | Dose | Indication | Notes |
|---|---|---|---|
| Epinephrine (Adrenalin) | 1 mg IV/IO q3–5 min | All cardiac arrest rhythms | Give immediately in PEA/asystole. After 2nd shock in VF/pVT. No max dose. |
| Amiodarone (Cordarone) | 300 mg IV/IO first dose, 150 mg second | Refractory VF/pVT | Give after 3rd shock. Alternative: lidocaine 1–1.5 mg/kg. |
| Lidocaine | 1–1.5 mg/kg IV first, 0.5–0.75 mg/kg repeat | Alternative to amiodarone for VF/pVT | Max 3 mg/kg total. |
| Atropine | 1 mg IV q3–5 min (max 3 mg) | Symptomatic bradycardia | NOT for cardiac arrest (removed from ACLS arrest algorithm). Still used for bradycardia with pulse. |
| Adenosine (Adenocard) | 6 mg rapid IV push → 12 mg → 12 mg | Stable regular narrow-complex SVT | Rapid push + immediate flush. Half-life 6 seconds. Warn patient: transient chest pressure/flushing. |
| Calcium chloride | 1–2 g (10–20 mL of 10%) IV slow push | Hyperkalemia, Ca-channel blocker OD, hypermagnesemia | Via central line preferred (tissue necrosis if infiltrates). Calcium gluconate 3g is alternative via peripheral. |
| Sodium bicarbonate | 1 mEq/kg IV | Hyperkalemia, TCA overdose, severe acidosis (pH < 7.1) | Not routine in cardiac arrest. Only for specific causes. |
| Magnesium sulfate | 1–2 g IV over 5–20 min | Torsades de Pointes, hypomagnesemia | First-line for Torsades. Also useful in refractory VF. |
Reversible Causes -H's & T's
| H's | Intervention |
|---|---|
| Hypovolemia | Volume resuscitation, blood products |
| Hypoxia | Secure airway, ventilate |
| Hydrogen ion (acidosis) | Bicarb, treat cause |
| Hypo/Hyperkalemia | Calcium, insulin/glucose, dialysis |
| Hypothermia | Active rewarming |
| T's | Intervention |
|---|---|
| Tension PTX | Needle decompression → chest tube |
| Tamponade | Pericardiocentesis |
| Toxins | Specific antidotes |
| Thrombosis (PE) | tPA 50 mg IV push |
| Thrombosis (MI) | PCI / cath lab |
Bradycardia with Pulse -Algorithm
Symptomatic? Hypotension, altered mental status, chest pain, acute HF → treat. Asymptomatic bradycardia → monitor.
1st Line
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 → 12 mg. If refractory: diltiazem or cardioversion. |
| 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
- → See full Post-Cardiac Arrest (ROSC) topic for details
Quick Reference
Analgesia Guide
Pain is the most undertreated ICU problem. Analgesia first -always. An "agitated" patient is often just a patient in pain. PADIS, 2018
ICU Opioid Comparison
| Feature | Fentanyl (Sublimaze) | Remifentanil (Ultiva) | Hydromorphone (Dilaudid) | Morphine (MS Contin) |
|---|---|---|---|---|
| ICU Role | 1st LINE | Specialized | 2nd Line | AVOID |
| Dose | Analgesia: 25–100 mcg/hr Analgo-sedation: 100–200+ mcg/hr PRN: 25–100 mcg q1h | 0.05–0.2 mcg/kg/min | 0.2–0.5 mg/hr or 0.2–1 mg IV q3–4h PRN | 2–4 mg IV q2–4h PRN |
| Potency (vs morphine) | 80–100× | 100–200× | 5–7× | 1× (reference) |
| Onset | 1–2 min | < 1 min | 5 min | 5–10 min |
| Duration (single dose) | 30–60 min | 3–5 min | 3–4 hrs | 3–5 hrs |
| Hemodynamic effect | Minimal -safest | Minimal | Mild hypotension | Hypotension (histamine release) |
| Renal failure | Safe (hepatic metabolism) | Safe (plasma esterases) | Caution (H3G at high doses) | AVOID -M6G accumulates → prolonged sedation, resp depression |
| Hepatic failure | Accumulates | Safe | Accumulates | Accumulates |
| Best for | Everything. Low dose = analgesia. High dose = analgo-sedation. Often sufficient alone. | Frequent neuro checks. Ultra-rapid offset. Procedural. | Alt to fentanyl. Better renal profile than morphine. | Palliative care only. Floor patients, opioid-naive. |
| Watch out | Chest wall rigidity (rapid bolus). Accumulates > 72h (lipophilic). | Expensive. Rapid tolerance. No analgesic effect after stopping. | Neuroexcitation (myoclonus) at very high doses in renal failure. | Histamine → bronchospasm. M6G. Hypotension. Avoid in asthma, CKD, ICU. |
Non-Opioid Adjuncts
| Drug (Brand) | Dose | Role | Key Notes |
|---|---|---|---|
| Acetaminophen (Ofirmev IV / Tylenol PO) | 650–1000 mg q6h (max 4g/day; 2g if liver disease) | Non-opioid baseline -schedule for ALL ICU patients | Reduces opioid need 20–30%. Very safe. Should be scheduled, not PRN. |
| Ketamine (Ketalar) -sub-dissociative | 0.1–0.3 mg/kg/hr IV | Opioid-sparing. Neuropathic pain. Bronchospasm. Hemodynamically unstable. | NMDA antagonist -synergistic with opioids. Reduces opioid use 30–50%. Bronchodilator. |
| Ketorolac (Toradol) | 15–30 mg IV q6h (max 5 days) | Short-term non-opioid. Post-op. Renal colic. | Avoid: renal failure, GI bleed, platelet dysfunction, elderly. Max 5 days. |
| Gabapentin (Neurontin) | 100–300 mg PO TID (renal dose!) | Neuropathic pain adjunct | Renally cleared -#1 cause of iatrogenic AMS in CKD patients. Always renal dose. |
| Lidocaine patch (Lidoderm 5%) | 1–3 patches, 12h on / 12h off | Localized pain (rib fractures, post-herpetic, incision site) | No systemic side effects. Underutilized opioid-sparing option. |
| Pregabalin (Lyrica) | 25–150 mg PO BID (renal dose!) | Neuropathic pain. Alternative to gabapentin. | Also renally cleared. Dose-adjust in CKD. Fewer drug interactions than gabapentin. |
Pain Assessment Tools
CPOT (intubated patients)
Facial expression + body movements + ventilator compliance + muscle tension. Score 0–8. ≥ 3 = significant pain.
NRS (awake patients)
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. | Egg/soy allergy, hypertriglyceridemia, propofol infusion syndrome risk | Hypotension (vasodilatory). Check TGs q48h. Propofol infusion syndrome if > 4 mg/kg/hr × > 48h. |
| Dexmedetomidine (Precedex) |
0.2–1.5 mcg/kg/hr IV (no load in ICU) | 15–30 min | Light sedation. Delirium prevention. Vent weaning. Only sedative without respiratory depression -can use in non-intubated patients. | Bradycardia, heart block, hemodynamic instability | Bradycardia (most common), hypotension, rebound HTN on discontinuation. Less delirium than benzos MENDS, 2007. |
| Ketamine (Ketalar) (Ketalar) |
0.5–2 mg/kg/hr IV (dissociative) 1–2 mg/kg bolus (procedural) |
1 min | Hemodynamically unstable (supports BP). Status asthmaticus. Refractory status epilepticus. Procedural. | Elevated ICP (relative), uncontrolled HTN, psychosis | Emergence phenomena, hypersalivation, tachycardia. Bronchodilator. |
| Midazolam (Versed) (Versed) 2ND/3RD LINE |
0.02–0.1 mg/kg/hr IV | 2–5 min | Benzo/alcohol withdrawal, status epilepticus, when propofol/dex contraindicated. | Prolonged ICU use, renal/hepatic failure, elderly | Accumulates → prolonged wake-up. ↑ delirium + mortality SEDCOM, 2009. Tolerance, withdrawal. |
| Lorazepam (Ativan) LAST RESORT |
0.01–0.1 mg/kg/hr IV or 0.5–4 mg PRN | 5 min | Alcohol/benzo withdrawal only (CIWA). Status epilepticus. Last resort. | Routine ICU sedation, renal failure (propylene glycol) | Propylene glycol toxicity (high-dose infusion). Worst delirium profile of all ICU sedatives. Do NOT use as first-line. |
RASS Scale -Sedation Targets
| RASS | Description | When to Target |
|---|---|---|
| +4 | Combative | - (never a target) |
| +3 | Very agitated | - (evaluate for pain, delirium, hypoxia) |
| +2 | Agitated | - (treat cause before escalating sedation) |
| +1 | Restless | May be acceptable if comfortable |
| 0 | Alert and calm | Ideal target for most patients |
| −1 | Drowsy -opens eyes to voice | Most common ICU target (RASS −1 to 0) |
| −2 | Light sedation -brief awakening to voice | Post-op, mild agitation |
| −3 | Moderate sedation -movement to voice only | NMB use, severe ARDS |
| −4 | Deep sedation -no response to voice | NMB, status epilepticus, elevated ICP |
| −5 | Unarousable | NMB only -reassess if unintentional |
Quick Selection Flowchart
Step 1: Pain controlled? (CPOT < 3, NRS ≤ 3) → If no, optimize analgesia first. Do not add sedation.
Step 2: Standard ventilated patient → Propofol. Target RASS −1 to 0. Daily SAT + SBT.
Step 3: Delirium, agitation, or vent weaning → Dexmedetomidine. Preserves respiratory drive.
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, 2007 SEDCOM, 2009. Never use as first-line ICU sedation.
Propofol infusion syndrome: > 4 mg/kg/hr × > 48h → new metabolic acidosis, ↑ lactate, rhabdomyolysis, Brugada-like ECG, cardiac failure. Stop propofol immediately, switch agent, supportive care.
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.
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
- Haloperidol 1–5 mg IV/IM q6–12h PRN -QTc monitoring required. MIND-USA, 2018
- Quetiapine 25–50 mg PO BID-TID -alternative in non-intubated patients
- Avoid: benzos (worsen delirium unless withdrawal), anticholinergics, polypharmacy
Neuromuscular Blockade (NMB)
- Indications: severe ARDS (P/F < 150), refractory dyssynchrony, elevated ICP, status epilepticus
- Cisatracurium preferred (Hofmann elimination -no renal/hepatic clearance)
- Always ensure adequate sedation AND analgesia before NMB -aware paralysis is catastrophic
- Train-of-four (TOF) monitoring -target 1–2 twitches out of 4
Procedural Sedation
| Procedure | Regimen |
|---|---|
| Bronchoscopy | Propofol 0.5–1 mg/kg bolus + fentanyl 25–50 mcg + topical lidocaine |
| Central / arterial line | 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, 2007 SEDCOM, 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.
🔍 Overview
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%.
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)
Pathophysiology -Why COPD Patients Crash
The core problem is dynamic hyperinflation:
Trigger (infection, irritant) → airway inflammation → mucus plugging + bronchospasm → prolonged expiratory time → incomplete exhalation → air trapping → progressive hyperinflation → flattened diaphragm → reduced inspiratory capacity → respiratory muscle fatigue → hypercapnic respiratory failure.
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.
Trigger (infection, irritant) → airway inflammation → mucus plugging + bronchospasm → prolonged expiratory time → incomplete exhalation → air trapping → progressive hyperinflation → flattened diaphragm → reduced inspiratory capacity → respiratory muscle fatigue → hypercapnic respiratory failure.
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.
The 6 P's -Common Triggers of AECOPD
Mnemonic: 6 P's -~80% of AECOPD exacerbations have an identifiable trigger. Think through each P systematically.
| # | P | Details |
|---|---|---|
| 1 | Pneumonia / Pulmonary infection | Most common trigger. Viral ~50% (rhinovirus, influenza, RSV, parainfluenza). Bacterial ~30% (H. influenzae, S. pneumoniae, M. catarrhalis). |
| 2 | Pulmonary embolism | Present in up to 25% of hospitalized AECOPD -often missed. Always consider if no clear infectious trigger, pleuritic pain, unexplained tachycardia, or hypoxia out of proportion. |
| 3 | Pneumothorax | Especially in emphysematous patients with bullae. CXR mandatory on all AECOPD admissions. |
| 4 | Pleural effusion | Can worsen dyspnea and restrict lung expansion. Rule out on CXR. |
| 5 | Poor compliance | Missed inhalers (LAMA/LABA/ICS non-adherence) -very common and modifiable. Always ask about medication use. |
| 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. |
Don't Miss PE: PE occurs in up to 25% of AECOPD hospitalizations. Consider CTPA if: no clear infectious trigger, pleuritic pain, unexplained tachycardia, or hypoxia out of proportion to exam findings.
Also consider: Heart failure exacerbation (can mimic or co-precipitate AECOPD -check BNP), temperature extremes, and aspiration.
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.
Clinical Presentation
Cardinal symptoms (Anthonisen criteria):
- Increased dyspnea -most sensitive symptom
- Increased sputum volume
- Increased sputum purulence -green/yellow suggests bacterial infection
Physical exam findings:
- Accessory muscle use (sternocleidomastoid, scalenes), tripod positioning
- Pursed-lip breathing (creates back-pressure to prevent airway collapse)
- Prolonged expiratory phase, diffuse expiratory wheezing
- Tachypnea (RR > 24), tachycardia, diaphoresis
- Cyanosis, asterixis (CO₂ retention), altered mental status
ICU Admission Criteria
- Severe dyspnea unresponsive to initial therapy (continued accessory muscle use, unable to speak in sentences)
- Altered mental status -confusion, somnolence, or coma
- Persistent hypoxemia: SpO₂ < 88% despite FiO₂ ≥ 0.4
- Severe or worsening respiratory acidosis: pH < 7.25 or PaCO₂ > 70 mmHg
- Acidosis not improving with NIV (recheck ABG at 1–2 hours)
- Hemodynamic instability requiring vasopressors
- NIV intolerance or failure
Key Point: A rising PaCO₂ with falling pH despite maximal therapy is an indication for intubation. Don't wait for respiratory arrest.
🧪 Workup & Diagnosis
Immediate Assessment
- ABG -mandatory in moderate-severe AECOPD. Assess pH, PaCO₂, PaO₂. Do NOT rely on SpO₂ alone.
- CXR -exclude pneumonia, pneumothorax, pulmonary edema, pleural effusion
- ECG -P pulmonale, right heart strain, arrhythmias (AF common in COPD)
- CBC -leukocytosis (infection), polycythaemia (chronic hypoxia)
- BMP -metabolic alkalosis (chronic CO₂ retainer), hypokalaemia (β₂ agonists)
- 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
Do NOT perform spirometry during acute exacerbation -results are unreliable and the maneuver is uncomfortable and potentially harmful. Review prior PFTs (baseline FEV₁) in the chart to understand severity. GOLD staging based on outpatient post-bronchodilator FEV₁/FVC < 0.70.
| GOLD Stage | Post-BD FEV₁ (% predicted) | Severity |
|---|---|---|
| GOLD 1 | ≥ 80% | Mild |
| GOLD 2 | 50–79% | Moderate |
| GOLD 3 | 30–49% | Severe |
| GOLD 4 | < 30% | Very severe |
GOLD A-B-E Groups (Symptom-Based Classification)
The GOLD 2023 update simplified COPD classification into 3 groups based on symptoms and exacerbation history. This guides outpatient treatment escalation -less relevant during acute exacerbation, but helps understand baseline therapy.
| GOLD Group | Symptoms (mMRC or CAT) | Exacerbations | Outpatient Treatment |
|---|---|---|---|
| Group A | Low symptoms (mMRC 0-1 or CAT < 10) |
0-1 (not requiring hospitalization) | Bronchodilator monotherapy: LABA or LAMA |
| Group B | High symptoms (mMRC ≥ 2 or CAT ≥ 10) |
0-1 (not requiring hospitalization) | Dual bronchodilator: LABA + LAMA |
| Group E | Any symptoms | ≥ 2 moderate exacerbations OR ≥ 1 hospitalization |
LABA + LAMA ± ICS (ICS if eosinophils ≥ 300 or frequent exacerbations) |
Key Change from Old GOLD: Groups C and D were merged into Group E. The "E" stands for Exacerbator phenotype -these patients have frequent exacerbations and need the most aggressive therapy. Blood eosinophils ≥ 300 cells/µL predict ICS benefit in Group E.
mMRC Dyspnea Scale: 0 = dyspnea only with strenuous exercise; 1 = dyspnea when hurrying on level or walking up slight hill; 2 = walks slower than people same age on level ground or stops for breath when walking at own pace; 3 = stops for breath after walking ~100 meters on level ground; 4 = too breathless to leave house.
CAT Score: COPD Assessment Test (0-40 scale). <10 = low impact, 10-20 = medium, 21-30 = high, >30 = very high impact.
CAT Score: COPD Assessment Test (0-40 scale). <10 = low impact, 10-20 = medium, 21-30 = high, >30 = very high impact.
🚨 Management
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:
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.
- Hypoxic drive suppression -Correcting hypoxia reduces peripheral chemoreceptor drive → hypoventilation (real but overemphasized).
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 nebuliser.
Albuterol (Ventolin, ProAir) 2.5–5 mg + ipratropium (Atrovent) 0.5 mg via nebuliser q20 min × 3, then q4–6h -or use DuoNeb (combination).
MDI + spacer equally effective as nebuliser in mild-moderate exacerbations (and doesn't aerosolise virus). Turner 1997
Continuous salbutamol nebuliser if severe bronchospasm.
Albuterol (Ventolin, ProAir) 2.5–5 mg + ipratropium (Atrovent) 0.5 mg via nebuliser q20 min × 3, then q4–6h -or use DuoNeb (combination).
MDI + spacer equally effective as nebuliser in mild-moderate exacerbations (and doesn't aerosolise virus). Turner 1997
Continuous salbutamol nebuliser if severe bronchospasm.
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 125 mg if unable to take PO (nil by mouth, vomiting) or very severe.
No taper needed for 5-day course. Taper only if > 3 weeks of steroids.
Use IV methylprednisolone 125 mg if unable to take PO (nil by mouth, vomiting) or very severe.
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 hospitalisation, recent abx).
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 hospitalisation, recent abx).
Non-Invasive Ventilation (NIV / BiPAP) -Before Intubation
Start NIV early in hypercapnic respiratory failure (pH < 7.35 + PaCO₂ > 45). Reduces intubation rates, ICU mortality, and length of stay. Brochard 1995; Plant 2000
Initial settings: IPAP 12–16 cmH₂O, EPAP 4–5 cmH₂O. Titrate IPAP for patient comfort + TV 6–8 mL/kg. Add supplemental O₂ to maintain SpO₂ 88–92%.
NIV Contraindications: Reduced consciousness, inability to protect airway, vomiting, facial trauma/burns, hemodynamic instability, copious secretions, pH < 7.15 with poor trajectory.
Initial settings: IPAP 12–16 cmH₂O, EPAP 4–5 cmH₂O. Titrate IPAP for patient comfort + TV 6–8 mL/kg. Add supplemental O₂ to maintain SpO₂ 88–92%.
NIV Contraindications: Reduced consciousness, inability to protect airway, vomiting, facial trauma/burns, hemodynamic instability, copious secretions, pH < 7.15 with poor trajectory.
Intubation -When NIV Fails or Contraindicated
RSI with cautious ventilator settings to avoid auto-PEEP.
Initial vent: TV 6–8 mL/kg IBW, 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.
Initial vent: TV 6–8 mL/kg IBW, 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 & Optimisation
- 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 counselling
- 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).
Bronchodilators: Albuterol (ProAir) 2.5mg + ipratropium (Atrovent) 0.5mg nebs q20min × 3, then q4h.
Steroids: Prednisone (Deltasone) 40mg PO daily × 5 days (REDUCE trial -5 days = 14 days in outcomes).
Antibiotics: Azithromycin (Zithromax) 500mg PO daily × 3 days (indicated because purulent sputum -meets ≥ 2 of 3 Anthonisen criteria: ↑ dyspnea, ↑ sputum volume, ↑ sputum purulence).
ABG: pH 7.31, PaCO₂ 58, PaO₂ 62 → acute-on-chronic respiratory acidosis. BiPAP initiated. Repeat ABG in 1–2h.
Key: If BiPAP fails (worsening acidosis, inability to protect airway, AMS) → intubate. But BiPAP prevents intubation in ~75% of COPD exacerbations.
📋 Case 2 — AECOPD Requiring Intubation
Patient: 74F with very severe COPD (FEV1 22%), brought in by EMS obtunded. RR 8, SpO₂ 78%, GCS 8. ABG: pH 7.12, PaCO₂ 95, PaO₂ 48.
This patient is too sick for BiPAP. Altered mental status + inability to protect airway = intubate.
Intubation strategy:
- Pre-oxygenate with BVM at low rate — avoid breath-stacking in COPD.
- RSI: Ketamine 1.5 mg/kg (bronchodilator properties, maintains hemodynamics) + rocuronium 1.2 mg/kg.
- Ventilator settings: Low RR (10–12), TV 6–8 mL/kg IBW, 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 125mg q6h → transition to PO). 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.
- Continue: Steroids, bronchodilators, O₂ targeting 88–92%.
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.
- Vaccinations: Influenza (annually), pneumococcal (PCV20), COVID, RSV (if ≥ 60).
- 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 q20 min × 3, then q4–6h | First-line. Watch hypokalaemia with frequent dosing. Check ECG. |
| Ipratropium (Atrovent) | SAMA | 0.5 mg neb q20 min × 3, then q6h | Combine with albuterol -additive bronchodilation. Less tachycardia. |
| Albuterol + Ipratropium (DuoNeb) | SABA+SAMA | 2.5/0.5 mg neb q20 min × 3 | Single-vial combination -preferred in acute setting for convenience |
| Magnesium sulphate | 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) | 125 mg IV q6h | Until able to take PO → switch | Use if nil by mouth / unable to absorb PO |
| Dexamethasone (Decadron) | 8 mg IV/PO daily | 5 days | Alternative; longer half-life, once-daily dosing |
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 |
| Azithromycin (Zithromax) | 500 mg PO × 1, then 250 mg daily × 4d | Atypical coverage, macrolide option | Resistance rates rising; QTc monitoring |
| Levofloxacin (Levaquin) | 500–750 mg PO/IV daily × 5–7d | Pseudomonas risk, structural lung disease, frequent hospitalisations | QTc prolongation; Achilles tendon rupture risk; reserve for high-resistance risk |
| Piperacillin-tazobactam (Zosyn) | 3.375g q6h IV | ICU-level AECOPD with Pseudomonas risk | Bronchiectasis, structural lung disease, prior Pseudomonas isolation |
Procalcitonin-Guided Antibiotics: PCT < 0.1 = unlikely bacterial → withhold antibiotics. PCT 0.1–0.25 = equivocal. PCT > 0.25 = bacterial → treat. Reduces antibiotic use without increasing mortality. PRORATA 2010
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. (3)
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.
Key findings: RR 28, SpO2 82% on RA, HR 110, accessory muscle use, tripod position. ABG on 2L NC: pH 7.28, PaCO2 78, PaO2 55. CXR: hyperinflation, no infiltrate. Procalcitonin 0.08.
Management:
- 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 Trial, 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.
Key findings: RR 20, SpO2 93% on RA, HR 88. Diffuse expiratory wheezing. ABG: pH 7.38, PaCO2 42. CXR: hyperinflation only. Procalcitonin 0.35.
Management:
- DuoNeb q4h, prednisone 40 mg PO daily x 5 days
- 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?
- Potassium -check daily with frequent nebs
- Glucose -steroid hyperglycaemia?
- Ambulation -physio ordered?
- Discharge planning -inhalers correct technique, follow-up, smoking cessation
Monitoring Protocol
| Parameter | Frequency | Target / Action |
|---|---|---|
| SpO₂ | Continuous | 88–92% in CO₂ retainers. NOT 94–98%. |
| ABG | 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 | Hypokalaemia with frequent salbutamol + steroids; replace aggressively |
| Glucose | q6h if on steroids | Steroid hyperglycaemia -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 IBW | 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
O₂ Target
88–92% in known/suspected CO₂ retainers. NOT high-flow. Titrate O₂ and check ABG in 30–60 min.
Bronchodilators
Albuterol (Ventolin) + ipratropium (Atrovent) neb q20 min × 3 → q4–6h, or DuoNeb. MDI + spacer equally effective in mild-moderate cases.
Steroids
Prednisolone 40 mg PO × 5 days. Equal to 14 days. IV methylprednisolone if nil by mouth. REDUCE 2013
Antibiotics
Give if 2–3 Anthonisen criteria present (dyspnea ↑ + sputum ↑ + purulence). Amox-clav or doxycycline × 5–7d. Fluoro if Pseudomonas risk.
NIV
Start early for pH < 7.35 + PaCO₂ > 45. Reduces intubation + mortality. Brochard 1995. Check ABG at 1–2h. Failure → intubate.
Intubation Settings
Low RR (10–12), I:E 1:3 to 1:4, low PEEP (3–5). High auto-PEEP → disconnect ETT + manual exhalation if hemodynamic collapse.
Don't Miss
PE in AECOPD (up to 25%). No infectious trigger → consider CTPA. Also AF (rate control) and HF co-exacerbation.
Before Discharge
Optimise inhalers (LAMA ± LABA ± ICS). Smoking cessation. Pulmonary rehab referral. Follow-up in 1–4 weeks.
📄 One Pager
Pulmonology · ICU · One Pager
AECOPD
Target O₂ 88–92%, NOT 94–98%. NIV before intubation. 5-day steroids. Antibiotics only if 2–3 Anthonisen criteria. Don't miss PE.
💨 Anthonisen Criteria
① Increased dyspnea
② Increased sputum volume
③ Increased sputum purulence
2–3 present → give antibiotics Anthonisen 1987
1 present → no antibiotic benefit
② Increased sputum volume
③ Increased sputum purulence
2–3 present → give antibiotics Anthonisen 1987
1 present → no antibiotic benefit
🩸 ABG -Severity Guide
pH 7.35–7.45 + ↑PaCO₂Chronic compensated
pH < 7.35 + ↑PaCO₂Acute -start NIV
pH < 7.25Severe -low threshold intubate
pH < 7.15Intubate -NIV failing
🚨 Management -Step by Step
1
O₂ target 88–92% -start 1–2L NC, titrate up. Check ABG at 30–60 min. Austin 2010
2
Bronchodilators: Albuterol (Ventolin) 2.5–5 mg + ipratropium (Atrovent) 0.5 mg neb q20 min × 3 → q4–6h, or DuoNeb
3
Steroids: Prednisolone 40 mg PO × 5 days REDUCE 2013
4
Antibiotics if ≥ 2 Anthonisen criteria: Amox-clav 875/125 mg BID or doxycycline × 5–7d
5
NIV (BiPAP) if pH < 7.35 + PaCO₂ > 45 -IPAP 12–16, EPAP 4–5. Check ABG at 1–2h. Brochard 1995
6
Intubate if NIV fails (pH worsening, AMS, RR still > 30). Low RR (10–12), I:E 1:3, low PEEP.
💊 Key Drugs
Albuterol (Ventolin)2.5–5 mg neb q20 min
Ipratropium0.5 mg neb q20 min
Prednisolone40 mg PO × 5d
Amox-clav875/125 mg PO BID × 5–7d
📊 Monitoring
- SpO₂ 88–92% target
- ABG at 1–2h after NIV start
- K⁺ daily (salbutamol + steroids)
- Glucose q6h (steroids)
- ECG -new AF common
⚠️ Pitfalls
- High-flow O₂ → CO₂ retention
- Steroids > 5 days (not needed)
- Antibiotics for viral AECOPD
- Missing PE as trigger
- High PEEP in auto-PEEP patient
- High RR on vent → air trapping
✅ NIV Success Criteria (check at 1–2h)
- pH improving toward 7.35
- PaCO₂ stable or falling
- RR decreasing
- More alert and cooperative
- Accessory muscle use decreasing
🎓 Key Trials
- Brochard 1995: NIV reduces intubation + mortality
- REDUCE 2013: 5d steroids = 14d
- Anthonisen 1987: Antibiotic criteria
- Austin 2010: Titrated O₂ reduces mortality 58%
- UPLIFT 2008: Tiotropium reduces exacerbations
Rounds · Pulmonology / ICU
GOLD Guidelines 2024 · REDUCE 2013 · Brochard 1995 · Austin 2010
Quick ReferenceICUWards
Bowel Regimen
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.
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.
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.
• 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.
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.
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.
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)
• 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
• 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)
• 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.
When to Use Inotropes
| Clinical Scenario | Hemodynamic Profile | Agent of Choice |
|---|---|---|
| Cardiogenic shock (acute MI, decompensated HFrEF) | ↓ CO, ↑ SVR, ↓ MAP, cold extremities, poor cap refill | Dobutamine (if BP adequate) or milrinone (if RV failure / pulm HTN). Add norepinephrine if MAP < 65. |
| Septic shock with cardiac dysfunction | ↓ CO despite adequate MAP on NE, poor ScvO₂ (< 70%), elevated lactate despite fluids + pressors | Dobutamine added to norepinephrine. Or epinephrine (provides both inotropy + vasopressor). SSC, 2021 |
| Acute RV failure (massive PE, pulm HTN crisis, RV infarct) | ↓ CO, ↑ CVP/JVP, ↑ PVR, RV dilation on echo, septal bowing | 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) |
↑ CO, ↓ SVR, ↓ PVR. "Inodilator" -inotropy + vasodilation. Better lusitropy (diastolic relaxation) than dobutamine. | 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). |
| Epinephrine (Adrenalin) 2ND LINE |
α₁ + β₁ + β₂ agonist | Low dose: 0.01–0.1 mcg/kg/min (β₁/β₂ dominant → inotropy + vasodilation) High dose: 0.1–0.5 mcg/kg/min (α₁ dominant → vasoconstriction + inotropy) |
↑ CO, ↑ HR, dose-dependent SVR. Low dose = inotrope. High dose = inopressor. | Refractory cardiogenic shock (need both inotropy + pressor). Cardiac arrest. Post-arrest low CO. Anaphylaxis. | Falsely elevates lactate (β₂-mediated aerobic glycolysis) -cannot use lactate to guide resuscitation. Arrhythmogenic. ↑ myocardial O₂ demand. Hyperglycemia. Mesenteric ischemia at high doses. |
| Dopamine (Intropin) AVOID |
Dose-dependent: D₁ (low) → β₁ (mid) → α₁ (high) | "Renal dose" 1–3 → "cardiac" 3–10 → "pressor" 10–20 mcg/kg/min | Variable. Unpredictable hemodynamics. | Avoid. Inferior to NE in shock SOAP II, 2010. Only remaining role: symptomatic bradycardia if no pacing. | More arrhythmias and higher mortality vs NE. "Renal-dose dopamine" is a myth -no renal protection Bellomo, 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. |
| Isoproterenol (Isuprel) SPECIALIZED |
Pure β₁ + β₂ agonist (no α) | 2–20 mcg/min IV | ↑ HR, ↑ CO, ↓ SVR. Potent chronotrope. | Symptomatic bradycardia (bridge to pacing). Torsades de Pointes (↑ HR shortens QT). Beta-blocker overdose. Post-heart transplant (denervated heart -atropine doesn't work). | Severe hypotension (↓ SVR via β₂). Massively increases myocardial O₂ demand. Arrhythmogenic. Never use in ischemia. |
| Digoxin (Lanoxin) ADJUNCT |
Na⁺/K⁺-ATPase inhibitor → ↑ intracellular Ca²⁺ | 0.125–0.25 mg PO/IV daily Load: 0.25–0.5 mg IV |
Mild ↑ CO, ↓ HR (vagotonic). Weak inotrope compared to IV agents. | Chronic HFrEF with persistent symptoms on GDMT. Afib rate control adjunct (especially HFrEF). DIG, 1997: reduced HF hospitalizations, no mortality benefit. | Narrow therapeutic window (target 0.5–0.9 ng/mL). Toxicity: any arrhythmia -classically "regularized Afib" (junctional rhythm), bigeminy, bidirectional VT. Hypokalemia potentiates toxicity. Renally cleared -dose-adjust. Reversal: digoxin-specific Fab (DigiFab). |
Inotrope vs Vasopressor -Know the Difference
| Feature | Inotrope | Vasopressor | Inopressor (Both) |
|---|---|---|---|
| Primary effect | ↑ Contractility (↑ CO) | ↑ SVR (↑ MAP) | ↑ CO + ↑ SVR |
| Main receptor | β₁, PDE3 | α₁, V1 | α₁ + β₁ |
| Examples | Dobutamine, milrinone | Phenylephrine, vasopressin | Norepinephrine, epinephrine |
| Effect on SVR | ↓ or neutral | ↑↑ | ↑ |
| Use when | CO is low, MAP is OK | MAP is low, CO is OK | Both MAP and CO are low |
| Cardiogenic shock | Yes (primary) | Only as adjunct for MAP | NE is first-line pressor in CS |
| Septic shock | Add if ↓ CO despite MAP-targeted NE | NE is first-line | Epi if refractory |
Decision Flowchart
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: more arrhythmias + higher mortality than NE. 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).
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 massive PE.
Risk Stratification — 2026 AHA/ACC Clinical Categories (A–E)
🚨 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 | 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). |
| B LOW SEVERITY | Symptomatic, low clinical severity | PESI ≤ 85 (class I–II), sPESI = 0, Hestia < 1. Normal hemodynamics. B1 = subsegmental, B2 = non-subsegmental. | Early discharge (24–48h or directly from ED) | DOAC (apixaban or rivaroxaban). No heparin bridge. Close follow-up in 48–72h HESTIA, 2011. |
| C ELEVATED SEVERITY | Elevated clinical severity score ± RV dysfunction ± biomarkers | 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 assessment for C2–C3 (Class 1). Close monitoring first 24–72h. Advanced therapy only if clinical deterioration. |
| D INCIPIENT FAILURE | Incipient cardiopulmonary failure | D1 = transient hypotension (SBP < 90 that responds to fluids/single pressor) D2 = normotensive shock (AKI, lactate ↑, oliguria, altered MS, ↑ O2 requirement, worsening RV strain) | Hospitalize — ICU/monitored bed | Anticoagulation + PERT (Class 1). CDT or mechanical thrombectomy may be considered (Class 2b). Systemic tPA if rapidly deteriorating. |
| E CARDIOPULMONARY FAILURE | Persistent hypotension / cardiac arrest | E1 = SBP < 90 for ≥ 15 min despite resuscitation, requiring vasopressors, or cardiac arrest | ICU. Emergent intervention. | Systemic thrombolysis (Class 1). CDT / mechanical thrombectomy (Class 2a). Surgical embolectomy if others unavailable. VA-ECMO as bridge. |
🔄 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.
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 massive PE (transient loss of CO). Present in ~10%
- 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).
Score > 4 (PE likely): Go directly to CTPA. Skip D-dimer (too many false positives).
🧪 Workup
Diagnostic Algorithm
Step-by-step: Clinical suspicion → PERC (if low risk) → Wells score → D-dimer (if Wells ≤ 4) → CTPA (if D-dimer positive or Wells > 4). Unstable patient → bedside echo → treat empirically.
Step 1
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 (massive vs submassive vs low-risk).
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 = submassive), 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 = submassive PE. 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. |
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, 2018 SELECT-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 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.
Category C3–D — Elevated Severity / Incipient Failure (formerly "Submassive PE")
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 submassive PE. 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 bleeding HI-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).
Category A–B — Subclinical / Low Severity (formerly "Low-Risk PE")
- 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, 2013 EINSTEIN-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:
- Hemodynamically unstable (SBP < 100, requiring pressors)
- Thrombolysis or embolectomy needed
- Active bleeding or high bleeding risk
- Need > 24h O2 to maintain SpO2 > 90%
- PE diagnosed while on anticoagulation
- Severe pain requiring IV analgesia > 24h
- Medical or social reason for admission (> 24h)
- CrCl < 30 mL/min
- Severe liver disease
- Pregnancy
- History of HIT
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. |
| FlowTriever | Mechanical aspiration thrombectomy. No lytic agent needed — purely mechanical clot removal. | 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. |
| Penumbra Indigo | Continuous aspiration mechanical thrombectomy (CAT). | 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 or DOAC. 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. |
IVC Filter Indications
- Absolute contraindication to anticoagulation (active life-threatening bleed) + acute proximal DVT/PE
- Recurrent PE despite therapeutic anticoagulation
- 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.
tPA Contraindications
| Absolute | Relative |
|---|---|
|
|
In cardiac arrest from massive PE, relative contraindications may be overridden. The risk of death from PE outweighs the bleeding risk. Discuss with your attending.
📋 Case 1 — Submassive 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 → Submassive PE
- sPESI score: age > 45 (+1), HR > 110 (+1) = 2 → high risk for decompensation
Treatment:
- Anticoagulation: Heparin drip (80 units/kg bolus → 18 units/kg/hr). Target aPTT 60-80.
- Disposition: ICU admission. Activate PERT if available.
- Monitor: Serial troponin q6h, repeat echo in 24h, continuous telemetry.
- Escalation plan: If SBP drops < 90, increasing O2, or worsening RV → catheter-directed therapy or half-dose tPA.
- Transition: Once stable × 24-48h → apixaban 10 mg BID × 7 days → 5 mg BID.
- Duration: Provoked (surgery) → 3 months. OCPs stopped.
📋 Case 2 — Massive PE with Cardiac Arrest
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 → massive 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%)
- Hestia criteria — all absent
Treatment:
- Outpatient management: sPESI = 0 + Hestia negative → safe for discharge.
- 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 submassive component 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)
- Thrombophilia workup: antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, beta-2 glycoprotein)
- 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 Severity
| Parameter | Massive / Submassive (ICU) | Low-Risk (Floor / Outpatient) |
|---|---|---|
| Vitals | Continuous telemetry + q1-2h. Arterial line if on pressors. | q4h. Continuous pulse ox × 24h. |
| Troponin | q6h × 24h then daily. Trending down = good. | Baseline if not already done. |
| BNP / NT-proBNP | Baseline + q24h. Falling = RV recovery. | Baseline only. |
| aPTT (if heparin drip) | q6h until therapeutic (60-80), then q12-24h. | N/A (on DOAC). |
| Platelet count | Baseline then q2-3 days (HIT screening if on heparin > 4 days). | Baseline. |
| Hemoglobin | Daily. Watch for bleeding (especially post-tPA). | Baseline. Repeat if bleeding signs. |
| Renal function | Daily BMP. Monitor Cr for contrast nephropathy (post-CTPA) and drug dosing. | Baseline. Confirm CrCl for DOAC dosing. |
| Echocardiography | Repeat in 24-48h for submassive. Assess RV recovery (TAPSE, RV/LV ratio). | Not routine. Only if symptoms persist. |
| Bleeding assessment | q shift: gums, GI (stool guaiac), hematuria, ecchymoses, access sites. | Educate patient on bleeding signs. |
| SpO2 / O2 requirement | Continuous. Increasing O2 need = deterioration → escalation. | Wean O2 to target SpO2 ≥ 92%. |
Escalation Triggers
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 submassive PE."
Key Points to Cover on Rounds
Submassive PE (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?
- Troponin/BNP trend? → Falling = good. Rising = RV strain worsening → consider escalation.
- RV function reassessment? → Repeat echo in 24-48h for submassive PE. 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. Submassive: when safe to step down from ICU?
💊 Medications & Doses
Anticoagulation
| Drug (Brand) | Dose | Monitoring | Reversal | Notes |
|---|---|---|---|---|
| Apixaban (Eliquis) 1ST LINE | 10 mg BID × 7 days → 5 mg BID Extended: 2.5 mg BID | No routine monitoring. Anti-Xa if needed (rare). | Andexanet alfa (Andexxa). PCC 50 units/kg if unavailable. | Lowest bleeding risk of all DOACs. No bridging. Preferred in CKD (less renal clearance). Avoid if CrCl < 25. AMPLIFY, 2013 |
| Rivaroxaban (Xarelto) 1ST LINE | 15 mg BID × 21 days → 20 mg daily Extended: 10 mg daily | No routine monitoring. | Andexanet alfa. PCC if unavailable. | No bridging. Must take with food (bioavailability drops 40% without). Caution if CrCl < 30. EINSTEIN-PE, 2012 |
| Heparin (UFH) MASSIVE/SUBMASSIVE | 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. |
| 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) MASSIVE PE | 100 mg IV over 2 hours Cardiac arrest: 50 mg IV bolus | Systemic IV | Standard of care for massive 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 submassive PE 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 submassive. |
Vasopressors for PE-Related Shock
| Agent | Dose | Why in PE | Avoid |
|---|---|---|---|
| Norepinephrine 1ST LINE | 0.01-3 mcg/kg/min | ↑ SVR + mild inotropy. Supports MAP without significantly increasing PVR. | - |
| Vasopressin ADJUNCT | 0.03 units/min (fixed) | 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
Diagnose
Low gestalt → PERC (if all 8 negative → stop). Otherwise → Wells ≤ 4 → D-dimer (age-adjusted). Wells > 4 → CTPA directly. Unstable → bedside echo → treat empirically.
Massive PE
SBP < 90 or cardiac arrest → systemic tPA 100 mg/2h (50 mg bolus in arrest). Cautious fluids (250-500 mL max). Norepi for MAP. Avoid intubation. CDT if tPA contraindicated. ECMO as bridge.
Submassive PE
Stable + RV strain (troponin, RV/LV > 0.9). Heparin drip. Activate PERT. Serial troponin + repeat echo. Escalate to CDT or half-dose tPA if deteriorating. PEITHO: no routine lysis.
Anticoagulation
DOAC first-line (apixaban 10→5 or rivaroxaban 15→20). No bridging. Duration: provoked = 3 months. Unprovoked = indefinite. Cancer = indefinite (avoid DOAC in GI cancers). APS = warfarin.
Outpatient PE
sPESI = 0 + Hestia criteria all negative → safe for home with DOAC + 48-72h follow-up. 30-day mortality ~1%. Same outcomes as inpatient.
Catheter-Directed
EKOS (low-dose tPA into PA), FlowTriever / Penumbra (mechanical, lytic-free). Lower bleeding than systemic tPA. For submassive deterioration or massive with tPA contraindication.
Special Populations
Pregnancy: LMWH (DOACs contraindicated). CKD: UFH if CrCl < 30. Cancer: LMWH or DOAC indefinitely. IVC filter: only if anticoag absolutely contraindicated. Always retrieve.
Don't Miss
CTEPH (4% of PE survivors -persistent dyspnea at 3-6 months → echo + V/Q). Paradoxical embolism (PFO + DVT → stroke). Subsegmental PE -may not need treatment if no DVT. HIT on heparin.
📄 One Pager
Pulmonology / Hematology · One Pager
Pulmonary Embolism
PE kills via RV failure, not hypoxia. PERC → Wells → D-dimer → CTPA. Massive = tPA. Submassive = 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.
Submassive (stable + RV strain): heparin drip. PERT. Serial troponin. Escalate if deteriorating.
Low-risk (sPESI 0 + Hestia negative): outpatient DOAC.
Submassive (stable + RV strain): heparin drip. PERT. Serial troponin. Escalate if deteriorating.
Low-risk (sPESI 0 + Hestia negative): outpatient DOAC.
💊 Key Drugs
Apixaban10 mg BID × 7d → 5 BID (1st line)
Rivaroxaban15 mg BID × 21d → 20 daily (with food)
Heparin (UFH)80 U/kg bolus → 18 U/kg/hr (aPTT 60-80)
Enoxaparin1 mg/kg SC q12h (pregnancy, bridge)
Alteplase (tPA)100 mg/2h systemic, 50 mg bolus in arrest
CDT (EKOS)12-24 mg tPA over 12-24h into PA
⏱️ Duration
Provoked: 3 months
Unprovoked: ≥ 6 months, consider indefinite
Recurrent: Indefinite (reduced-dose DOAC)
Cancer: Indefinite (LMWH or DOAC, avoid DOAC in GI cancers)
APS: Warfarin (DOACs inferior)
Unprovoked: ≥ 6 months, consider indefinite
Recurrent: Indefinite (reduced-dose DOAC)
Cancer: Indefinite (LMWH or DOAC, avoid DOAC in GI cancers)
APS: Warfarin (DOACs inferior)
🫀 RV Failure Principles
Fluids: 250-500 mL MAX (RV volume-sensitive). Pressors: norepi 1st line (avoid phenylephrine → ↑ PVR). Intubation: avoid if possible (PPV ↓ preload → PEA). If must: ketamine, low PEEP, pressors running first.
⚠️ Pitfalls
- D-dimer without Wells/PERC (ordering reflexively)
- Aggressive fluids in massive PE (worsens RV failure)
- Intubation without hemodynamic preparation
- Missing submassive PE (not checking troponin/BNP)
- Routine tPA for submassive (PEITHO: ↑ bleeding)
- Not considering outpatient treatment for sPESI 0
- Forgetting CTEPH screening at 3-6 months
- DOACs in pregnancy or APS
RoundsRx · Pulmonology / Hematology
ESC PE 2019 · AMPLIFY · EINSTEIN-PE · PEITHO · MOPETT · ULTIMA · Hokusai-VTE Cancer · HESTIA
EmergentICU
Hyperkalemia
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) | Urgent -start treatment |
| 6.0–6.5 | Prolonged PR interval, flattened P waves | Emergent |
| 6.5–7.0 | Widened QRS (> 120 ms) | Critical -calcium NOW |
| 7.0–8.0 | Sine wave pattern (QRS merges with T wave) | Pre-arrest. Calcium + emergent dialysis. |
| > 8.0 | VF, asystole, PEA | Cardiac arrest. Treat during resuscitation. |
Common Causes
- Renal failure (AKI, CKD G4–G5) -most common, impaired K⁺ excretion
- Medications -ACEi/ARBs, spironolactone, trimethoprim, NSAIDs, heparin, succinylcholine
- Cellular shift -acidosis, rhabdomyolysis, tumor lysis, DKA, massive transfusion
- Adrenal insufficiency -cortisol + aldosterone deficiency → impaired renal K⁺ excretion
- 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 |
| Hemolysis index | Elevated (lab flags specimen as hemolyzed) | Normal (non-hemolyzed sample) |
| Serum vs. plasma K⁺ | Serum K⁺ significantly higher than plasma K⁺ (difference > 0.3–0.4 mEq/L) | Serum and plasma K⁺ are concordant |
| Clinical context | 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 |
| 3c. REMOVE | Sodium zirconium cyclosilicate (Lokelma) CHRONIC/SUBACUTE | 10 g PO TID × 48h (acute) → 5–10 g daily | 1–2 hrs | Ongoing | 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). (3)
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
- Insulin 10U IV + D50 (shift K⁺ intracellularly, onset 15-30 min)
- Albuterol 10 mg continuous neb (additive shift, lowers K⁺ 0.5-1.0 mEq/L)
- 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.
Key findings: K⁺ 7.8, phosphate 8.2, uric acid 14.5, Ca²⁺ 6.8, LDH 4,200, Cr 3.6. Classic tumor lysis syndrome (TLS).
Management:
- 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.
Monitoring
- ECG after each intervention
- K⁺ at 1h and 2h
- Glucose at 1h post-insulin
- Continuous telemetry if >6.5
- UOP
⚡ Summary
Summary
ECG Changes
Peaked T waves → flattened P → widened QRS → sine wave → VF/asystole. ECG changes ≠ K⁺ level (treat ECG, not number).
Stabilize
Calcium gluconate 1g IV (onset 1-3 min, duration 30-60 min). Protects myocardium. Does NOT lower K⁺.
Shift K⁺
Insulin 10 units + D50 (best shifter, onset 15-30 min). Albuterol 10-20 mg neb (additive). Bicarb only if pH < 7.2.
Eliminate K⁺
Patiromer/Lokelma (gut, hours -avoid kayexalate). Furosemide (renal, if UOP). Dialysis (definitive, immediate clearance during session).
Common Causes
RAAS inhibitors (ACEi/ARB + spironolactone), CKD, rhabdomyolysis, tumor lysis, acidosis, tissue necrosis, hemolysis.
Pseudo-hyperK
Hemolyzed sample (#1 cause), prolonged tourniquet, fist clenching, extreme leukocytosis/thrombocytosis. Recheck before treating.
📄 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.
💊 Common Causes
RAAS inhibitors (ACEi + spironolactone), CKD, rhabdomyolysis, tumor lysis, acidosis, hemolysis, tissue necrosis. Always check for pseudo-hyperK (hemolyzed sample).
💊 Key Drugs
Calcium gluconate1g IV over 5 min
Regular insulin10 units IV + D50
Albuterol10-20 mg continuous neb
Kayexalate15-30g PO
⚠️ Pitfalls
- Insulin without D50 (hypoglycemia)
- Not checking ECG
- Not holding offending meds (ACEi, spironolactone, TMP-SMX)
- Treating hemolyzed sample
RoundsRx · Nephrology / Emergency
AHA Hyperkalemia 2020 · KDIGO
EmergentICU
Alcohol Withdrawal & DTs
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.
Monitoring
- CIWA q1-2h
- Vitals q1-4h
- Mg, K, PO₄ q12h
- Seizure precautions
- DT watch 48-72h
- Blood glucose
🔍 Overview
Timeline of Withdrawal
| Time After Last Drink | Syndrome | Features |
|---|---|---|
| 6–12 hours | Minor withdrawal | Tremor, anxiety, insomnia, nausea, tachycardia, hypertension, diaphoresis |
| 12–24 hours | Alcoholic hallucinosis | 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.
🚨 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.
| CIWA Score | Severity | Action |
|---|---|---|
| < 8 | Minimal | Monitor q4–8h. Supportive care. Thiamine, folate, banana bag. |
| 8–15 | Mild-moderate | Lorazepam 1–2 mg PO/IV q1h PRN. Reassess in 1h. |
| 16–20 | Moderate-severe | Lorazepam 2–4 mg IV q1h. Consider ICU admission. |
| > 20 | Severe / impending DTs | ICU. Lorazepam 4 mg IV q15–30 min until controlled. Consider phenobarbital. Load aggressively. |
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
Patient: 48M, daily vodka drinker (1 pint/day × 15 years), last drink 14 hours ago. Tremor, anxiety, tachycardia (HR 108), diaphoresis. CIWA score: 18.
| Time | CIWA | Action |
|---|---|---|
| Hour 0 | 18 (moderate-severe) | Lorazepam (Ativan) 2mg IV. Thiamine (Vitamin B1) 500mg IV (give BEFORE any glucose). Banana bag is NOT adequate thiamine -need 500mg IV. |
| Hour 1 | 16 | Lorazepam (Ativan) 2mg IV. Replete Mg (MgSO₄ 2g IV), K⁺, PO₄. |
| Hour 2 | 14 | 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).
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.
📋 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).
📣 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
Timeline
6-12h: tremor, anxiety, tachycardia. 12-24h: hallucinations. 12-48h: seizures (GTC, brief, self-limited). 48-72h: delirium tremens (5-15% mortality).
CIWA Protocol
Symptom-triggered benzodiazepines. CIWA ≥ 8 → treat. Lorazepam 1-2 mg IV q1h PRN (preferred in liver disease -no active metabolites).
Thiamine
500 mg IV × 3 days → 100 mg PO daily. Give BEFORE glucose. Prevents Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia).
DT Risk Factors
Prior DTs (#1), prior withdrawal seizures, heavy daily use, concurrent illness, older age, high initial CIWA.
Seizure Prophylaxis
Benzodiazepines (not phenytoin -phenytoin does NOT prevent alcohol withdrawal seizures). Lorazepam or diazepam.
Replete
Mg²⁺ (universally depleted), K⁺ (often low), PO₄, folate 1 mg daily, MVI. Banana bag is NOT adequate thiamine dosing.
📄 One Pager
Addiction / ICU · One Pager
Alcohol Withdrawal
CIWA-driven benzos. Thiamine 500mg IV BEFORE glucose × 3 days. Watch for DTs at 48-72h. Seizures at 12-48h. Replete Mg/K/PO₄.
🧪 Timeline
6-12h: tremor, anxiety, tachycardia. 12-24h: hallucinations. 12-48h: seizures (brief GTCs). 48-72h: delirium tremens (mortality 5-15% if untreated).
🚨 Management
CIWA protocol: symptom-triggered lorazepam 1-2 mg IV q1h PRN. Thiamine 500 mg IV × 3 days BEFORE glucose. Folate 1 mg, MVI. Replete Mg²⁺, K⁺, PO₄. Benzo-resistant → phenobarbital.
⚠️ DT Risk Factors
Prior DTs (#1 predictor), prior withdrawal seizures, heavy daily use, concurrent illness, older age, high initial CIWA > 20. DTs peak at 48-72h.
💊 Key Drugs
Lorazepam1-4 mg IV q1h PRN (CIWA ≥ 8)
Thiamine500 mg IV × 3d → 100 PO
Phenobarbital130-260 mg IV (benzo-resistant)
Diazepam10-20 mg IV (long-acting option)
⚠️ Pitfalls
- Glucose before thiamine (precipitates Wernicke)
- Phenytoin for alcohol withdrawal seizures (doesn't work)
- Banana bag = inadequate thiamine (only 100 mg)
- Under-dosing benzos in DTs
RoundsRx · Addiction / ICU
ASAM Alcohol Withdrawal 2020
EmergentGI
Acute Pancreatitis
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.
Monitoring
🔍 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).
Etiology -"I GET SMASHED"
| Letter | Cause | % of Cases |
|---|---|---|
| I | Idiopathic | ~10–15% |
| G | Gallstones | ~40% (most common) |
| E | Ethanol | ~30% (2nd most common) |
| T | Trauma / tumor | ~2–5% |
| S | Steroids / scorpion stings | Rare |
| M | Mumps / autoimmune | Rare |
| A | Autoimmune (IgG4) | ~2% |
| S | Sphincter of Oddi dysfunction | Rare |
| H | Hyperlipidemia / Hypercalcemia / Hypothermia | TG > 1000 → ~5% |
| E | ERCP | ~5% post-ERCP |
| D | Drugs (azathioprine, valproic acid, didanosine, mesalamine) | ~2% |
Severity (Revised Atlanta Classification)
| Severity | Definition | Mortality |
|---|---|---|
| Mild (~80%) | No organ failure, no local complications | < 1% |
| Moderately severe (~15%) | 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. Aggressive IVF
Lactated Ringer's preferred de-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-inferior WATERFALL, 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
| Complication | Timing | Management |
|---|---|---|
| Acute peripancreatic fluid collection | < 4 weeks | Usually resolves spontaneously. No intervention unless infected. |
| Pancreatic pseudocyst | > 4 weeks, encapsulated | Drain if symptomatic (> 6 cm, infected, obstructing). EUS-guided drainage preferred. |
| Acute necrotic collection | < 4 weeks | Sterile → supportive. Infected → antibiotics + delayed drainage (wait ≥ 4 weeks if stable for walled-off necrosis to mature). |
| Walled-off necrosis (WON) | > 4 weeks, encapsulated | If infected: step-up approach -antibiotics → percutaneous/endoscopic drainage → surgical necrosectomy only if drainage fails PANTER, 2010. |
| Splenic vein thrombosis | Variable | Left-sided portal HTN → isolated gastric varices. Anticoagulation if symptomatic. Splenectomy if refractory GI bleeding. |
📋 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.
Complications to watch: Necrotizing pancreatitis (infected necrosis → antibiotics + drainage), pseudocyst (>4 weeks), pancreatic abscess. Infected necrosis = carbapenems + IR/surgical drainage.
🧪 Workup
Workup
- Lipase >3× ULN
- BMP, CBC, LFTs, Ca²⁺
- RUQ US -ALL patients
- Triglycerides
- CRP at 48h
- MRCP if CBD dilated
- CT at 72h+ only if worsening
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| LR | 1.5mL/kg/hr | IV | Goal-directed hydration |
| Hydromorphone | 0.5-1mg q3-4h | IV | Multimodal pain |
| Ketorolac | 15-30mg q6h×5d | IV | NSAID adjunct |
| No prophylactic abx | - | - | Unless infected necrosis |
📋 On Rounds
Pimp Questions
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)
- Aggressive IVF with LR (3 mL/kg/hr initially) de-Madaria, 2018
- 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.
Key findings: Lipase 3,800, triglycerides 4,200 mg/dL, glucose 380, HbA1c 12.4%. Lipemic serum. CT: peripancreatic stranding without necrosis.
Management:
- Insulin drip 0.1-0.3 units/kg/hr — activates lipoprotein lipase to clear TGs rapidly
- Add D5 to prevent hypoglycemia during insulin infusion
- Strict NPO until TG < 500 (dietary fat raises TG further)
- 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: aggressive IVF with LR (initial bolus then 3 mL/kg/hr), 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
Monitoring
⚡ Summary
Summary
Diagnosis
2 of 3: (1) characteristic epigastric pain radiating to back, (2) lipase > 3× ULN, (3) imaging findings. Lipase is more specific than amylase.
Treatment
Aggressive IVF (LR, 3 mL/kg/hr initially), pain control, early oral feeding (don't keep NPO). No prophylactic antibiotics.
Severity
BISAP score, APACHE II, Ranson's at 48h. CT severity: Balthazar. Persistent organ failure (> 48h) = severe.
Etiology
Gallstones (#1, ~40%) → US + LFTs + MRCP. Alcohol (#2, ~30%). Hypertriglyceridemia (> 1000) → insulin drip. Drug-induced, ERCP, autoimmune.
Gallstone Panc
RUQ US → if stones + CBD dilated → MRCP or ERCP. Cholangitis → ERCP within 24h. Cholecystectomy this admission.
Complications
Necrotizing: CT at 72h+ if worsening. Walled-off necrosis: drain only if infected (gas on CT, +culture). Pseudocyst: observe unless symptomatic.
📄 One Pager
GI · One Pager
Acute Pancreatitis
2 of 3: epigastric pain + lipase > 3× + imaging findings. Aggressive IVF + 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
Aggressive 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
RoundsRx · GI
ACG Pancreatitis 2013 · AGA 2018
Monitoring -Hyperkalemia
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
EmergentNeurology
Acute Ischemic Stroke
Time is brain. Every minute of ischemia = ~1.9 million neurons lost. Know the tPA window, thrombectomy criteria, 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 tPA (alteplase) 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, 1995 ECASS III, 2008 |
| IV tenecteplase EMERGING | ≤ 4.5 hours | 0.25 mg/kg IV bolus (single push -no infusion). Easier to administer than alteplase. | AcT, 2022: tenecteplase non-inferior to alteplase. Increasingly used as first-line. |
| Mechanical thrombectomy LVO | ≤ 24 hours (with perfusion imaging) | Large vessel occlusion (LVO): ICA, M1, M1-equivalent. NIHSS ≥ 6. ≤ 6h: CTA showing LVO is sufficient MR CLEAN, 2015 ESCAPE, 2015. 6–24h: requires perfusion mismatch on CT perfusion or MR-DWI DAWN, 2018 DEFUSE 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.
tPA Contraindications (Major)
- Active internal bleeding or bleeding diathesis
- Platelets < 100,000, INR > 1.7, aPTT > 40, PT > 15
- Recent surgery/trauma (within 14 days major, 3 months head)
- History of ICH
- BP > 185/110 despite treatment (must lower before tPA)
- Glucose < 50 (correct first -hypoglycemia mimics stroke)
- On DOACs within 48h (or anti-Xa > measurable level)
🚨 Management
Acute Stroke Protocol
0 min -Door
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.
📋 Clinical Example -Acute Ischemic Stroke tPA Decision
Patient: 72M, last known well 2 hours ago, found with right-sided weakness and aphasia. NIHSS 14.
Time is brain -target door-to-needle ≤ 60 min:
📋 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 tPA in acute ischemic stroke?
Absolute contraindications (within 4.5h window): (1) Active internal bleeding, (2) History of hemorrhagic stroke (any time), (3) Ischemic stroke or head trauma within 3 months, (4) Intracranial neoplasm, AVM, or aneurysm, (5) Known bleeding diathesis (platelets < 100K, INR > 1.7, aPTT elevated, on DOACs with last dose < 48h), (6) SBP > 185 or DBP > 110 that cannot be controlled, (7)
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 — 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 3 — 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, R MCA LVO. NIHSS 18. CT negative for hemorrhage. tPA 0.9 mg/kg administered at 2.5h from onset. Thrombectomy team activated -successful TIMI 2b recanalization. Post-procedure NIHSS 8 (improving). BP target <180/105 (post-tPA). Dysphagia screen: failed → NPO, NGT placed. Etiology: Afib (not anticoagulated -was never started). Plan: start apixaban once 24h imaging confirms no hemorrhagic conversion. PT/OT/SLP. Secondary prevention workup.
Monitoring -Hyperkalemia
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Hyperkalemia
Workup for Hyperkalemia: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Hyperkalemia
Medication details for Hyperkalemia are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
tPA Window
0-4.5h from last known well. Door-to-needle ≤ 60 min. 0.9 mg/kg (max 90 mg), 10% bolus → remainder over 1h.
Thrombectomy
LVO (M1, ICA, basilar) up to 24h with favorable perfusion imaging (mismatch) [DAWN, DEFUSE-3]. CTA confirms LVO. CT perfusion guides extended window.
BP Management
Pre-tPA: allow up to 220/120. If tPA → target < 185/110 before, < 180/105 after × 24h. Permissive hypertension maintains perfusion.
Secondary Prevention
Antiplatelet (ASA ± clopidogrel × 21 days for minor stroke [CHANCE, POINT]). Statin. Anticoagulation for AF (start after 24h imaging). Treat HTN, DM, smoking.
Dysphagia Screen
Before ANY oral intake. Failed → NPO, NGT for meds/nutrition. Aspiration pneumonia is a major cause of post-stroke mortality.
Rehab
PT/OT/SLP early. Stroke unit care reduces mortality. Discharge planning starts day 1.
📄 One Pager
One Pager -Hyperkalemia
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
HYPERKALEMIA -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
Neurology · One Pager
Acute Ischemic Stroke
tPA within 4.5h. Thrombectomy for LVO up to 24h with mismatch imaging. Door-to-needle ≤ 60 min. Dysphagia screen before PO.
🧪 Diagnosis
Acute focal neurologic deficit. CT head to rule out hemorrhage. CTA for LVO. CT perfusion for extended window (mismatch). NIHSS for severity.
Antiplatelet: ASA ± clopidogrel × 21 days [CHANCE, POINT]. Statin: atorvastatin 80. AF → anticoag (start after 24h imaging confirms no hemorrhagic conversion). BP, DM, smoking management.
💊 Key Drugs
Alteplase0.9 mg/kg (max 90 mg)
ASA325 mg (after 24h post-tPA)
Clopidogrel75 mg (dual antiplatelet × 21d)
Atorvastatin80 mg daily
⚠️ Pitfalls
- Delaying tPA for detailed neuro exam (time is brain)
- Not checking glucose first (hypoglycemia mimics stroke)
- Not doing dysphagia screen before any PO intake
- Missing posterior circulation stroke (vertigo, ataxia, diplopia)
RoundsRx · Neurology
AHA/ASA Stroke 2019 · DAWN · DEFUSE-3
EmergentGI / Surgical
Acute Mesenteric Ischemia
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. | |
| Mesenteric venous thrombosis (~10%) | SMV thrombosis → venous congestion → mucosal ischemia | More insidious onset (days). Risk: hypercoagulable states, portal HTN, recent surgery, OCP use. | |
| Non-occlusive (NOMI) (~15%) | Splanchnic vasoconstriction in low-flow states | 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).
- Nausea, vomiting, bloody diarrhea (late -mucosal sloughing)
- Elevated lactate (often markedly, > 4–5) -but normal lactate does NOT rule it out early
- Leukocytosis, metabolic acidosis, elevated LDH
- Risk factors: Afib, recent MI, CHF, PVD, vasopressor use, hypercoagulable state
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.
Diagnosis
| Test | Findings |
|---|---|
| CT angiography (CTA) TEST OF CHOICE | Sensitivity > 95%. [ACG Guidelines, Defined 2005 Shows arterial/venous filling defects, bowel wall thickening, pneumatosis (gas in bowel wall = necrosis), portal venous gas, free fluid. |
| Lactate | 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 drip Acosta, 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%. T
🧪 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)
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. (3)
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
- Aggressive atherosclerotic risk factor management (statin, ASA, smoking cessation)
- 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
Classic Presentation
Severe abdominal pain OUT OF PROPORTION to exam. Elderly + Afib or atherosclerosis. Pain first, peritonitis late (= bowel death).
Imaging
CTA abdomen/pelvis (sensitivity > 95%). Don't wait for lactate -it's a LATE marker (elevated = tissue already dying).
Types
Arterial embolism (50%, sudden, Afib), arterial thrombosis (25%, gradual, prior angina), venous (10%, subacute, hypercoag), NOMI (15%, low-flow state).
Treatment
SMA embolism: embolectomy or catheter-directed lysis. SMA thrombosis: surgical revascularization. SMV thrombosis: anticoagulation. NOMI: optimize hemodynamics.
Surgery
Emergent if peritoneal signs, perforation, or worsening despite intervention. Second-look laparotomy at 24-48h to assess bowel viability.
Mortality
60-80% overall mortality. Key to survival: early diagnosis (before bowel infarction) + rapid intervention. "Think about it to diagnose it."
📄 One Pager
GI / Surgery · One Pager
Mesenteric Ischemia
Pain out of proportion to exam. CTA immediately. Don't wait for lactate (late marker). Surgical emergency if peritonitis. Mortality 60-80% if delayed.
🧪 Presentation
Severe acute abdominal pain OUT OF PROPORTION to physical exam. Elderly + Afib or atherosclerosis. Peritonitis = late sign = bowel already dead.
🚨 Management
CTA abdomen/pelvis immediately (sensitivity > 95%). SMA embolism → embolectomy. SMA thrombosis → revascularization. SMV thrombosis → anticoagulation. NOMI → optimize hemodynamics.
⚠️ Types
Arterial embolism (50%, sudden, Afib). Arterial thrombosis (25%, gradual, prior intestinal angina). Venous (10%, subacute, hypercoagulable). NOMI (15%, low-flow state on pressors).
💊 Key Drugs
HeparinAnticoag for all types
Broad-spectrum abxPip-tazo (if peritonitis)
PapaverineIntra-arterial (NOMI)
IVFAggressive resuscitation
⚠️ Pitfalls
- Reassured by benign abdominal exam (early ischemia = soft abdomen + severe pain)
- Waiting for lactate to elevate (late marker)
- Not thinking about it (must suspect to diagnose)
- Delaying surgical consult
RoundsRx · GI / Surgery
ACG Mesenteric Ischemia 2020
PulmonologyCommon
Pleural Effusion
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.
Complicated Parapneumonic / Empyema
| Category | Fluid Features | Management |
|---|---|---|
| Simple parapneumonic | Clear, pH > 7.2, glucose > 60, LDH < 1000, culture negative | Antibiotics alone. May not need drainage. |
| Complicated parapneumonic | pH < 7.2, glucose < 60, LDH > 1000, or positive gram stain/culture | Chest tube drainage + antibiotics. Consider tPA/DNase instillation MIST2, 2011. |
| Empyema | Frankly purulent fluid or positive culture | 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.
Management:
- Check serum-pleural albumin gradient: 1.8 g/dL (> 1.2 confirms true transudate)
- This is a Light's criteria false-positive — diuretics concentrated the pleural protein
- No further invasive workup needed; treat underlying CHF
- Optimize diuresis (uptitrate furosemide, add metolazone if needed)
- If recurrent despite optimal HF management → consider tunneled pleural catheter
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.
Management:
- Chest tube placement — complicated parapneumonic effusion (pH < 7.2, glucose < 60, positive gram stain)
- Broaden antibiotics: vancomycin + piperacillin-tazobactam
- 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 -Alcohol Withdrawal & DTs
Workup for Alcohol Withdrawal & DTs: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Alcohol Withdrawal & DTs
Medication details for Alcohol Withdrawal & DTs are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Light's Criteria
Exudate if ANY 1: protein ratio > 0.5, LDH ratio > 0.6, fluid LDH > 2/3 serum ULN. Sensitive but misclassifies 25% of transudates (especially diuresed CHF).
Transudate
CHF (#1), cirrhosis, nephrotic. Treatment: treat underlying cause (diuresis for CHF). Thoracentesis for symptomatic relief.
Exudate Workup
Cell count + diff, gram stain + culture, glucose, pH, LDH, cytology. If lymphocytic: TB (ADA), malignancy. If PMN: parapneumonic, empyema.
Parapneumonic
Uncomplicated (pH > 7.2, glucose > 60): abx alone. Complicated (pH < 7.2, glucose < 60, positive culture): chest tube. Empyema (frank pus): tube + surgery.
Malignant
Cytology positive or pleural biopsy positive. Recurrent → tunneled pleural catheter (PleurX) or chemical pleurodesis (talc).
False Exudate
If clinical picture = transudate but Light's says exudate → check serum-effusion albumin gradient. > 1.2 g/dL = transudate (likely diuresed CHF).
📄 One Pager
One Pager -Alcohol Withdrawal & DTs
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
ALCOHOL WITHDRAWAL & DTS -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
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.
🚨 Workup by Type
Transudate: CHF, cirrhosis, nephrotic → treat underlying cause. Exudate: send cell count, gram stain, culture, glucose, pH, LDH, cytology. Lymphocytic → TB (ADA), malignancy.
💊 Parapneumonic Management
Uncomplicated (pH > 7.2, glc > 60): abx only. Complicated (pH < 7.2, glc < 60, +culture): chest tube + abx. Empyema (frank pus): chest tube + surgery consult. tPA/DNase for loculated effusions MIST2, 2011.
💊 Key Drugs
Diagnostic thoracentesisAll new effusions
Albumin gradientIf Light's doesn't match clinical picture
tPA + DNaseLoculated parapneumonic [MIST2
PleurX catheterRecurrent malignant effusion
⚠️ Pitfalls
- Not doing thoracentesis on new effusion (it's the test)
- Missing false exudate in diuresed CHF (check albumin gradient)
- Not sending pH/glucose on parapneumonic effusion (determines tube need)
- Chest tube delay in empyema
RoundsRx · Pulmonology
BTS Pleural Disease 2023 · MIST2 2011
PulmonologyCommon
Pneumonia
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 | MRSA, Pseudomonas, Klebsiella, Acinetobacter, Enterobacter | 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, 2024 |
| 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.
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.
What defines "severe" pneumonia? (ATS/IDSA 2019)
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, temp < 36°C, hypotension requiring aggressive fluids.
Severe pneumonia gets broader coverage -add vanc or linezolid (MRSA) ± anti-pseudomonal agent. Linezolid preferred over vanc in severe MRSA pneumonia due to superior lung penetration.
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, temp < 36°C, hypotension requiring aggressive fluids.
Severe pneumonia gets broader coverage -add vanc or linezolid (MRSA) ± anti-pseudomonal agent. Linezolid preferred over vanc in severe MRSA pneumonia due to superior lung penetration.
CURB-65 (CAP Severity)
| Criterion | 1 Point Each |
|---|---|
| C | Confusion (new AMS) |
| U | Urea (BUN) > 20 mg/dL |
| R | Respiratory rate ≥ 30 |
| B | Blood pressure: SBP < 90 or DBP ≤ 60 |
| 65 | Age ≥ 65 |
0–1: outpatient treatment. 2: consider admission (short stay). 3–5: admit, consider ICU if ≥ 4.
💊 Treatment
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: 5 days minimum Short-Course CAP Trial, 2016 -no benefit of longer courses if clinically stable at day 5. |
| 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. |
| 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 days ATS/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. |
Pip-Tazo vs Cefepime -When to Use Which
💊 Piperacillin-Tazobactam (Zosyn)
Coverage: Pseudomonas + gram-negatives + anaerobes
- Aspiration with abscess/empyema/necrotizing PNA -anaerobic coverage built in
- Intra-abdominal co-infection suspected
- Poor dentition + indolent course (anaerobes likely)
- Post-obstructive pneumonia (distal to tumor)
- Mixed aerobic-anaerobic infection
⚠️ AKI risk with vancomycin: Pip-tazo + vanc has significantly higher AKI rates than cefepime + vanc ACORN, 2024 Pip-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
- Preferred when combining with vancomycin -lower AKI risk ACORN, 2024
- 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.
| Feature | Vancomycin | Linezolid (Zyvox) |
|---|---|---|
| Route | IV only (PO only for C. diff) | IV and PO (100% PO bioavailability) |
| MOA | Cell wall inhibitor -binds D-Ala-D-Ala, blocks peptidoglycan cross-linking. Bactericidal (slowly). | 50S ribosome inhibitor -blocks 70S initiation complex → stops protein synthesis. Bacteriostatic. Also a weak MAOi (→ serotonin syndrome risk). |
| VRE | ✗ No | ✓ Yes |
| Lung penetration | Poor (~25%) | Excellent (~100%) -key advantage in pneumonia |
| Renal dosing | Yes -trough/AUC monitoring required | No adjustment needed |
| Max duration | No hard limit | ≤ 14 days (thrombocytopenia risk) |
| Key toxicity | Nephrotoxicity, Red Man Syndrome, ototoxicity | Thrombocytopenia (> 14d), serotonin syndrome (MAOi), lactic acidosis, peripheral neuropathy (may be irreversible), optic neuritis (> 28d), myelosuppression |
🏆 Vancomycin Wins
- MRSA bacteremia / endocarditis
- Osteomyelitis (long-duration OK)
- Default empiric MRSA coverage
- Patient on SSRIs (serotonin risk with linezolid)
🏆 Linezolid Wins
- MRSA pneumonia (superior lung penetration) ZEPHyR, 2012
- VRE infections
- CKD / AKI (no renal adjustment)
- No IV access / outpatient Tx (PO = IV)
🧫 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), Urea > 7 mmol/L (0), RR ≥ 30 (0), BP < 90 systolic (0), Age ≥ 65 (0) = Score 0 → outpatient treatment appropriate.
But: SpO₂ 94% borderline + looks unwell → admit for observation.
Inpatient non-ICU CAP:
- Ceftriaxone (Rocephin) 1g IV daily + azithromycin (Zithromax) 500mg IV/PO daily
- 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: 5 days total if afebrile ≥ 48h and ≤ 1 sign of clinical instability (CAP-START trial). No need for 7–14 days.
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: treat CAP for 7–14 days. Current evidence: 5 days is sufficient if patient is afebrile ≥48h and has ≤1 sign of clinical instability. Some data supports even 3 days in select patients. Longer courses increase C. difficile risk, resistance, and side effects without improving cure rates.
📋 On Rounds
Can you use 5 days of antibiotics for CAP?
Yes. Short-Course CAP Trial, 2016 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.
Key findings: RR 24, SpO₂ 91% on RA. CXR: RLL consolidation. WBC 16K, procalcitonin 2.8. CURB-65 = 2 (age + BUN 24). Blood cultures x2 drawn.
Management:
- 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 Short-Course CAP Trial, 2016 — 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
- Ceftriaxone + azithromycin + vancomycin (cavitary lesions + recent hospitalization = MRSA risk)
- 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.
Key findings: Temp 38.2°C, RR 22, SpO₂ 93% on 2L NC. CXR: RLL infiltrate (dependent segment). WBC 13K, procalcitonin 0.4.
Management:
- 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 Short-Course CAP Trial, 2016. Follow-up CXR in 6-8 weeks (rule out underlying mass).
🧪 Workup
Workup -Pneumonia
- History: Cough (productive vs dry), fever/chills, dyspnea, pleuritic chest pain, sick contacts, travel, immunosuppression, recent hospitalization/abx (within 90 days)
- Physical exam: Tachypnea, crackles/bronchial breath sounds, dullness to percussion, egophony, tactile fremitus
- Labs: CBC, BMP, procalcitonin (guides abx duration), lactate if sepsis concern, blood cultures ×2 (before abx in severe/ICU), sputum culture + Gram stain
- Imaging: CXR PA + lateral (infiltrate, consolidation, effusion). CT chest if CXR equivocal or complications suspected
- Urine antigens: Legionella (serogroup 1) + S. pneumoniae -order in ICU-level or severe CAP
- MRSA nasal swab: NPV > 95% -if negative, can safely de-escalate vanc/linezolid
- Procalcitonin: < 0.25 → bacterial unlikely. Serial levels guide antibiotic de-escalation (drop > 80% from peak → safe to stop)
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
Outpatient CAP
Healthy: amoxicillin 1g TID × 5 days. Comorbidities: amox-clav + azithromycin, or respiratory FQ (levofloxacin). Avoid FQ for uncomplicated.
Inpatient (non-ICU)
Ceftriaxone 1g IV + azithromycin 500 IV. Alternative: respiratory FQ monotherapy (levofloxacin 750 daily).
ICU CAP
Ceftriaxone + azithromycin + vancomycin (if MRSA risk). MRSA nasal swab: negative = de-escalate vanc (NPV > 95%).
Duration
5 days if: afebrile ≥ 48h, improving, no more than 1 instability criterion Short-Course CAP Trial, 2016. Don't treat longer just because CXR hasn't cleared.
Follow-Up CXR
6-8 weeks post-treatment (rule out underlying malignancy, especially if smoker, age > 50, or slow to resolve).
Aspiration
Chemical pneumonitis (sterile) = NO abx. Bacterial aspiration PNA = treat like CAP (ceftriaxone + azithro). Anaerobes are NOT the primary cause. Add anaerobic coverage (amp-sulbactam, pip-tazo) ONLY if abscess, empyema, or necrotizing PNA.
📄 One Pager
Pulmonology / ID · One Pager
Community-Acquired Pneumonia
Outpatient: amoxicillin (healthy) or amox-clav + azithro (comorbidities). Inpatient: ceftriaxone + azithromycin. ICU: add vanc if MRSA risk. Duration: 5 days if stable × 48h.
🧪 Severity
CURB-65: Confusion, Urea > 20, RR ≥ 30, BP < 90/60, age ≥ 65. 0-1: outpatient. 2: admit. ≥ 3: ICU consideration. ATS/IDSA: 1 major criterion or ≥ 3 minor = ICU.
🚨 Empiric Treatment
Outpatient (healthy): amoxicillin 1g TID × 5d. Outpatient (comorbid): amox-clav + azithro or respiratory FQ. Inpatient (non-ICU): ceftriaxone + azithromycin. ICU: ceftriaxone + azithro ± vancomycin if MRSA risk.
💊 Key Principles
Duration: 5 days if afebrile ≥ 48h + improving Short-Course CAP Trial, 2016. MRSA nasal swab: negative NPV > 95% → de-escalate vancomycin. Follow-up CXR at 6-8 weeks (rule out mass, especially smoker > 50).
💊 Key Drugs
Ceftriaxone1g IV daily
Azithromycin500 mg IV/PO daily
Amoxicillin1g TID (outpatient)
Vancomycin15-20 mg/kg (MRSA risk)
⚠️ Pitfalls
- Treating > 5 days without indication (short course is standard)
- FQ for uncomplicated outpatient CAP (reserve for comorbidities)
- Not getting follow-up CXR at 6-8 weeks in smokers
- Forgetting atypical coverage (azithromycin) for inpatient CAP
RoundsRx · Pulmonology / ID
ATS/IDSA CAP 2019 · Short-Course CAP Trial 2016
PulmonologyOutpatient
Pulmonary Nodule & Lung Cancer Screening
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), (5)
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 -Acute Ischemic Stroke
Workup for Acute Ischemic Stroke: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Acute Ischemic Stroke
Medication details for Acute Ischemic Stroke are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Fleischner
Solid nodule ≥ 8mm → CT at 3 months, PET-CT, or biopsy based on risk. < 6mm in low-risk: no follow-up. Part-solid: longer follow-up, lower threshold for biopsy.
High-Risk Features
Size > 8mm, upper lobe, spiculated, part-solid, growing, smoker, age > 50, FH lung cancer.
PET-CT
For solid nodules ≥ 8mm with intermediate probability of malignancy. PET avid → biopsy or resect. PET negative → follow with serial CT.
Part-Solid
Highest malignancy rate of any nodule type. GGO component may represent lepidic adenocarcinoma. Longer follow-up (5 years). Low threshold for biopsy if solid component > 5mm.
Document Everything
Incidental nodules lost to follow-up = major malpractice risk. Document finding, risk assessment, specific follow-up plan with date, and communicate to patient.
Lung-Rads
Used for LDCT screening findings (different from Fleischner which is for incidental nodules). Categories 1-4 guide follow-up intervals.
📄 One Pager
One Pager -Acute Ischemic Stroke
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
ACUTE ISCHEMIC STROKE -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🔍 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.
⚡ Management
Management -Pulmonary Nodule & Lung Cancer Screening
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
📄 One Pager
Pulmonology · One Pager
Pulmonary Nodule
Fleischner guidelines for incidental nodules. High-risk features: > 8mm, upper lobe, spiculated, part-solid, smoker. PET-CT for intermediate probability. DOCUMENT and follow up.
🧪 Risk Assessment
Size (> 8mm), morphology (part-solid = highest malignancy rate, spiculated), location (upper lobe), patient factors (smoker, age > 50, FH lung cancer, COPD).
🚨 Fleischner Guidelines
💊 Key Drugs
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)
RoundsRx · Pulmonology
Fleischner Society 2017 · Lung-Rads · NCCN Lung Screening
Monitoring
- PFTs q6-12mo
- FVC decline >5-10%/yr in ILD → escalate
- DLCO <40% → O₂+transplant eval
- 6MWT
PulmonologyDiagnostic
PFT Interpretation
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.
🔍 Systematic Interpretation
Step 1 -FEV₁/FVC Ratio
| FEV₁/FVC | Pattern | Examples |
|---|---|---|
| < 0.70 (or < LLN) | Obstructive GOLD Criteria, 2024 | COPD, asthma, bronchiectasis, bronchiolitis obliterans |
| Normal or ↑ | Restrictive (if TLC reduced) | ILD (IPF, sarcoidosis), chest wall disease, neuromuscular (ALS, myasthenia), obesity |
| ↓ with ↓ TLC | Mixed | Combined COPD + ILD, sarcoidosis |
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
- Positive → suggests asthma (reversible obstruction)
- Negative → suggests COPD (fixed obstruction), but some COPD patients have partial reversibility
Step 3 -DLCO (Diffusion Capacity)
| DLCO | Pattern | Think |
|---|---|---|
| Low DLCO + Obstruction | Emphysema (parenchymal destruction) | COPD (emphysema phenotype). Asthma has NORMAL DLCO -key differentiator. |
| Low DLCO + Restriction | Interstitial lung disease | IPF, sarcoidosis, hypersensitivity pneumonitis, drug-induced ILD |
| Low DLCO + Normal spirometry | Pulmonary vascular disease | Pulmonary hypertension, PE, early ILD |
| Normal/↑ DLCO + Restriction | Extrapulmonary restriction | Obesity, neuromuscular disease, chest wall deformity (lungs are normal) |
| ↑ DLCO | Increased pulmonary blood flow | Diffuse alveolar hemorrhage, polycythemia, L-to-R shunt, asthma, obesity |
Lung Volumes Summary
| Volume | Obstructive | Restrictive |
|---|---|---|
| TLC | ↑ or normal (hyperinflation, air trapping) | ↓ (< 80% predicted) |
| RV | ↑↑ (air trapping) | ↓ or normal |
| RV/TLC ratio | ↑ | Normal or ↓ |
| FRC | ↑ | ↓ |
🧪 Workup
Workup
- Spirometry -FEV₁, FVC, ratio
- Lung volumes -TLC (confirm restriction)
- DLCO -low=emphysema/ILD; normal=asthma
- Bronchodilator response
- Methacholine challenge
- Flow-volume loop
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Albuterol neb | 2.5mg | Neb | Reversibility testing |
| PFTs are diagnostic | not therapeutic | - | - |
📋 On Rounds
How do you distinguish asthma from COPD on PFTs?
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. (4)
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.
Clinical Examples
📋 Case 1 — Obstructive Pattern (COPD)
Patient: 64M, 45-pack-year smoker. Progressive dyspnea × 3 years. PFTs: FEV₁ 42% predicted, FVC 78%, FEV₁/FVC 0.54, DLCO 48%. Post-bronchodilator: FEV₁ improves 6% and 90 mL.
Key findings: Obstructive pattern: FEV₁/FVC < 0.70 (the defining ratio). Low DLCO = emphysema (alveolar destruction). Minimal bronchodilator response (< 12% AND < 200 mL) = COPD, not asthma. GOLD Stage III (severe: FEV₁ 30-49%).
Management:
- LABA/LAMA combination inhaler (first-line for symptomatic COPD GOLD B-E)
- Add ICS only if eosinophils > 300 or frequent exacerbations despite dual bronchodilators
- Smoking cessation (the ONLY intervention proven to slow FEV₁ decline)
- Pulmonary rehab referral (improves exercise capacity, dyspnea, and QOL)
- Annual PFTs to track FEV₁ decline (normal: ~30 mL/yr; COPD smoker: 60-100 mL/yr)
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.
📋 Case 2 — Restrictive Pattern (IPF)
Patient: 70F with progressive dyspnea and dry cough × 18 months. Bibasilar velcro crackles. PFTs: FEV₁ 62%, FVC 58%, FEV₁/FVC 0.85 (normal ratio), TLC 65%, DLCO 38%.
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
Obstructive
FEV₁/FVC < 0.70. COPD (fixed) vs asthma (reversible: ≥ 12% AND ≥ 200 mL improvement post-bronchodilator).
Restrictive
FEV₁/FVC normal or elevated. TLC reduced (requires lung volumes). ILD, obesity, neuromuscular disease, chest wall deformity.
DLCO
Low: emphysema, ILD, pulmonary HTN, anemia, PE. Normal despite obstruction: asthma (parenchyma intact). Elevated: pulmonary hemorrhage, polycythemia.
COPD Staging
GOLD: FEV₁ ≥ 80% (I/mild), 50-79% (II/moderate), 30-49% (III/severe), < 30% (IV/very severe). Combined with symptoms + exacerbation history for treatment. GOLD, 2024
Flow-Volume Loop
Upper airway obstruction: flattened inspiratory limb (variable extrathoracic) or flattened expiratory limb (variable intrathoracic) or both (fixed).
Bronchoprovocation
Methacholine challenge: fall in FEV₁ ≥ 20% = positive (hyperreactive airways = asthma). Used when PFTs are normal but asthma is clinically suspected.
⚡ Management
Management -PFT Interpretation
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
📄 One Pager
Pulmonology · One Pager
Pulmonary Function Tests
FEV₁/FVC < 0.70 = obstruction. Reversibility (≥ 12% + 200 mL) = asthma. Low DLCO = emphysema/ILD/pulm HTN (normal in asthma). TLC needed to confirm restriction.
🧪 Obstructive Pattern
FEV₁/FVC < 0.70. COPD: no significant reversibility, low DLCO. Asthma: significant reversibility (≥ 12% AND ≥ 200 mL), normal DLCO. COPD staging: GOLD I-IV by FEV₁ %.
🚨 Restrictive Pattern
FEV₁/FVC normal or elevated + reduced TLC (need lung volumes). Causes: ILD (low DLCO), neuromuscular (normal DLCO), obesity (normal DLCO), chest wall deformity.
💊 DLCO Interpretation
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)
RoundsRx · Pulmonology
ATS/ERS PFT Standards 2022 · GOLD 2024
Monitoring -Acute Mesenteric Ischemia
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
EmergentPulmonology
Pneumothorax
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%). |
| Secondary spontaneous (SSP) | Underlying lung disease (COPD, CF, Pneumocystis, ILD, LAM) | More dangerous -limited pulmonary reserve. Even small PTX can cause significant compromise. Lower threshold for intervention. |
| Traumatic | Blunt/penetrating chest trauma, rib fractures | Chest tube. Evaluate for hemothorax (check pleural Hct). |
| Iatrogenic | Central line (subclavian > IJ), thoracentesis, lung biopsy, positive pressure ventilation | Post-procedure CXR. Small iatrogenic PTX in stable patient → may observe. |
| Tension | One-way valve effect → progressive air trapping → mediastinal shift → ↓ venous return → hemodynamic collapse | CLINICAL DIAGNOSIS: hypotension + JVD + absent breath sounds + tracheal deviation away. Needle decompression BEFORE imaging. 14–16G needle, 2nd ICS, midclavicular line (or 5th ICS, anterior axillary line). |
🚨 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
- Supplemental O₂ (increases nitrogen gradient → accelerates pneumothorax reabsorption 4×)
- 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
- Careful O₂ titration — target SpO₂ 88-92% (COPD CO₂ retainer risk)
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
- VATS: resect apical blebs + abrade parietal pleura → adhesion formation prevents recurrence (< 5% recurrence after VATS)
- 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.
Monitoring -Acute Mesenteric Ischemia
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Acute Mesenteric Ischemia
Workup for Acute Mesenteric Ischemia: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Acute Mesenteric Ischemia
Medication details for Acute Mesenteric Ischemia are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Tension PTX
Clinical diagnosis -don't wait for imaging. Absent breath sounds, tracheal deviation, hypotension, JVD. Needle decompress immediately (2nd ICS MCL or 4th/5th ICS AAL).
Primary Spontaneous
Tall thin young male. Small (< 2cm) + minimal symptoms → observe + O₂ + repeat CXR. Large or symptomatic → aspiration or chest tube.
Secondary
COPD, ILD, CF, PCP. Lower threshold for intervention (these patients can't tolerate lung loss). All ≥ 1cm or symptomatic → chest tube + admit.
Chest Tube
14-28 Fr pigtail or surgical chest tube. Connect to water seal or suction. Post-procedure CXR. Remove when: no air leak + lung expanded on CXR × 12-24h.
Recurrence
30% after 1st episode, 60% after 2nd. After 2nd → VATS with pleurodesis (chemical or mechanical). Prevents recurrence.
Counseling
No flying × 2 weeks post-resolution. No scuba diving ever (unless pleurodesis performed). Return if sudden chest pain or dyspnea.
📄 One Pager
One Pager -Acute Mesenteric Ischemia
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
ACUTE MESENTERIC ISCHEMIA -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
Pulmonology / Emergency · One Pager
Pneumothorax
Tension = clinical diagnosis → needle decompress immediately. Primary spontaneous: small → observe, large → aspiration/tube. Secondary: lower threshold for tube. Recurrence → VATS + pleurodesis.
🧪 Types
Primary spontaneous: tall thin young male, no lung disease. Secondary: COPD, ILD, CF, PCP (lower threshold for intervention -can't tolerate lung loss). Tension: one-way valve → obstructive shock.
🚨 Tension PTX -Don't Wait for Imaging
Absent breath sounds + tracheal deviation + hypotension + JVD. Needle decompress: 14-16G, 2nd ICS MCL or 4th/5th ICS AAL. Then chest tube. Clinical diagnosis -decompress first, image after.
💊 Management
Small primary (<2cm) + minimal symptoms → observe + O₂ + repeat CXR. Large/symptomatic → aspiration or chest tube (14-28 Fr pigtail). Remove tube when: no air leak + expanded on CXR × 12-24h.
💊 Key Drugs
Needle decompression14-16G, 2nd ICS MCL (tension)
Pigtail chest tube14 Fr (small catheter)
Supplemental O₂Accelerates reabsorption
Pain controlOpioids/NSAIDs as needed
⚠️ Pitfalls
- Waiting for CXR in tension PTX (clinical diagnosis → decompress)
- Discharging without recurrence counseling (30% after 1st episode)
- Not admitting secondary PTX (these patients decompensate quickly)
- Flying within 2 weeks (risk of re-expansion)
RoundsRx · Pulmonology / Emergency
BTS Pneumothorax 2023 · ACEP
PulmonologyChronic
Obstructive Sleep Apnea
Recurrent upper airway obstruction during sleep → intermittent hypoxia, sleep fragmentation, and systemic inflammation. Affects ~15–30% of adults. Strongly associated with HTN, Afib, HF, stroke, and perioperative complications.
🔍 Overview
Diagnosis
- Polysomnography (PSG) = gold standard. Measures AHI (apnea-hypopnea index).
- Home sleep apnea testing (HSAT) -acceptable for uncomplicated suspected OSA (no significant comorbidities). Underestimates AHI.
| AHI | Severity | Treatment |
|---|---|---|
| 5–14 | Mild | CPAP if symptomatic. Weight loss, positional therapy, oral appliance. |
| 15–29 | Moderate | CPAP recommended. Weight loss. |
| ≥ 30 | Severe | CPAP strongly recommended. Significant CV risk if untreated. |
Screening -STOP-BANG
| Letter | Question |
|---|---|
| S | Snoring loudly? |
| T | Tired / daytime sleepiness? |
| O | Observed apneas during sleep? |
| P | Pressure -treated for HTN? |
| B | BMI > 35? |
| A | Age > 50? |
| N | Neck circumference > 40 cm (16 in)? |
| G | Gender -male? |
≥ 3: high risk for OSA → formal sleep study. ≥ 5: high probability of moderate-severe OSA.
Cardiovascular Consequences
- Resistant hypertension -OSA is the #1 cause of resistant HTN. Screen all patients with HTN on ≥ 3 drugs.
- Atrial fibrillation -OSA increases Afib risk 2–4×. Untreated OSA increases Afib recurrence after cardioversion and ablation.
- Heart failure -intermittent hypoxia → increased afterload → RV/LV dysfunction
- Stroke -independent risk factor
- Pulmonary hypertension -chronic intermittent hypoxia → pulmonary vasoconstriction
OSA vs OHS (Obesity Hypoventilation Syndrome)
⚠️ 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
- Minimize opioids -multimodal analgesia (acetaminophen, NSAIDs, regional anesthesia)
- Continuous pulse oximetry (not just spot checks)
- Semi-upright positioning (not flat supine)
- Avoid benzodiazepines
📋 On Rounds
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. (4)
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: (1)
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.
Management:
- Auto-CPAP titration — start 4-20 cmH₂O auto-adjusting (most patients need 8-12 cmH₂O)
- 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)
- Perioperative precautions: CPAP at bedside post-op, minimize opioids (use multimodal analgesia), continuous pulse oximetry, semi-upright positioning
- Avoid benzodiazepines (worsen upper airway collapse)
- 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.
📋 Case 3 — Obesity Hypoventilation Syndrome (OHS)
Patient: 58M, BMI 52, presents with progressive dyspnea, lower extremity edema, somnolence. ABG: pH 7.32, PaCO₂ 58, PaO₂ 52, HCO₃ 34. Hgb 18.2 (polycythemia). Echo: RV dilation, estimated RVSP 55 mmHg. Sleep study: AHI 62.
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.
Monitoring -Obstructive Sleep Apnea
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Obstructive Sleep Apnea
Workup for Obstructive Sleep Apnea: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 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. |
| Acetazolamide (Diamox) | 250mg PO BID | Carbonic anhydrase inhibitor → metabolic acidosis → stimulates ventilation | 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
Diagnosis
AHI ≥ 5 + symptoms (EDS, witnessed apneas, morning headache) OR AHI ≥ 15 regardless of symptoms. Home sleep test or in-lab PSG.
CPAP
Gold standard. Adherence target: ≥ 4h/night, ≥ 70% of nights. Auto-titrating most common. Proper mask fitting critical. Follow-up data download at 4 weeks.
CV Consequences
#1 cause of resistant HTN. Doubles AF recurrence. Associated with: stroke, MI, HF, pulmonary HTN. CPAP improves BP and AF outcomes.
Alternatives
Oral appliance (mild-moderate). Inspire (hypoglossal nerve stimulator, moderate-severe who can't tolerate CPAP). Positional therapy. Weight loss (semaglutide).
Perioperative Risk
Higher risk of difficult intubation, post-op respiratory depression (opioid sensitivity), desaturation. Bring home CPAP to hospital. Alert anesthesia.
Weight Loss Impact
Each 10% weight loss reduces AHI by ~26%. Semaglutide for obesity + OSA is an emerging treatment strategy. GLP-1 RA may directly reduce AHI.
📄 One Pager
One Pager -Obstructive Sleep Apnea
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
OBSTRUCTIVE SLEEP APNEA -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
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.
🚨 Treatment
CPAP (gold standard). Adherence target: ≥ 4h/night, ≥ 70% of nights. Auto-titrating most common. Alternatives: oral appliance (mild-moderate), Inspire hypoglossal nerve stimulator, positional therapy, weight loss.
💊 CV Consequences
#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.
💊 Key Drugs
CPAPAuto-titrating, proper mask fit
Weight lossGLP-1 RA may reduce AHI
ModafinilIf residual EDS despite CPAP
Oral applianceMild-moderate OSA
⚠️ Pitfalls
- Not screening resistant HTN patients for OSA
- Poor CPAP adherence (mask fitting + education + follow-up critical)
- Not bringing home CPAP to hospital (perioperative risk)
- Prescribing sedatives/opioids without screening for OSA
RoundsRx · Pulmonology / Sleep
AASM OSA 2015 · SAVE Trial
Monitoring -Pleural Effusion
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
PulmonologyChronic
Interstitial Lung Disease
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. | CTD-ILD (RA, scleroderma), drug-induced, idiopathic NSIP | Better than UIP. Often responds to immunosuppression. |
| Organizing Pneumonia (OP) | Peripheral, patchy consolidations that may be migratory. "Reverse halo" (atoll sign). | COP (cryptogenic), drug-induced, post-infection, CTD | Good. Usually responds dramatically to steroids. |
| Upper-lobe predominant | Fibrosis/nodules in upper lobes | Sarcoidosis, hypersensitivity pneumonitis (chronic), silicosis, coal workers | Variable |
IPF (Idiopathic Pulmonary Fibrosis)
- Most common IIP. Male > female. Typically age > 60. Smoking is a risk factor.
- Clinical: progressive exertional dyspnea, dry cough, bibasilar Velcro-like crackles on auscultation, clubbing (~50%)
- PFTs: restrictive pattern (↓ FVC, ↓ TLC) + ↓↓ DLCO
- Diagnosis: UIP pattern on HRCT in appropriate clinical context → may not need biopsy. If HRCT indeterminate → surgical lung biopsy via VATS for confirmation.
Sarcoidosis
ANTIFIBROTIC
ANTIFIBROTIC
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.
Monitoring -Pleural Effusion
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Pleural Effusion
Workup for Pleural Effusion: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Pleural Effusion
Medication details for Pleural Effusion are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
IPF
UIP pattern on HRCT (basal honeycombing, traction bronchiectasis). Antifibrotics only (nintedanib or pirfenidone). NO steroids [PANTHER-IPF harm]. Transplant referral early.
NSIP
GGO-predominant on HRCT. Often associated with CTD (especially scleroderma). Responds to immunosuppression (mycophenolate + steroids). Better prognosis than IPF.
COP
Organizing pneumonia: migratory infiltrates, responds dramatically to steroids. Relapses common → slow taper over months.
CTD-ILD
ILD from autoimmune disease (RA, scleroderma, SLE, myositis). Screen all new ILD for CTD (ANA, RF, CCP, myositis panel). Treat underlying autoimmune disease.
Monitoring
PFTs (FVC, DLCO) q6 months. HRCT annually or with symptoms. 6MWT. Refer for transplant: FVC declining > 5-10%/year, DLCO < 40%, O₂ requirement.
Pulmonary Rehab
Improves exercise capacity, dyspnea, QOL even in progressive disease. Refer early, don't wait for O₂ dependence. Combine with antifibrotics for maximum benefit.
📄 One Pager
One Pager -Pleural Effusion
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
PLEURAL EFFUSION -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
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)
- Forgetting pulmonary rehab (dramatically improves QOL)
RoundsRx · Pulmonology
ATS/ERS IPF 2022 · PANTHER-IPF 2012 · SENSCIS
EmergentPulmonology
Hemoptysis
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 |
| Parenchymal | Pneumonia, TB (cavitary), lung abscess, fungal (aspergilloma) |
| Vascular | PE, AV malformations, Dieulafoy lesion (bronchial artery), mitral stenosis |
| Diffuse alveolar hemorrhage (DAH) | Vasculitis (GPA, anti-GBM), SLE, coagulopathy. Bilateral GGOs on CT + dropping Hgb + hemoptysis. |
| Iatrogenic | 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
- Emergent interventional radiology: bronchial artery embolization (BAE) — ~90% immediate success rate
- 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)
- Staging: PET/CT, brain MRI, mediastinal lymph node sampling
- 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.
📋 Case 3 — Diffuse Alveolar Hemorrhage (DAH)
Patient: 35M with hemoptysis, dyspnea, Hgb dropping 12 → 7 over 48h. CXR: bilateral diffuse infiltrates. BAL: sequential aliquots increasingly bloody (confirms DAH). Cr 4.2 (rising). c-ANCA/PR3 positive.
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 -Pneumonia
Workup for Pneumonia: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Pneumonia
Medication details for Pneumonia are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
Most Common Cause
Acute bronchitis (#1 overall). But always consider: malignancy (> 40, smoker), bronchiectasis, TB, PE, vasculitis (DAH).
Massive (> 500 mL/24h)
Airway emergency. Bleeding side DOWN. Intubate (large ETT ≥ 8.0). Bronchoscopy for localization. IR for bronchial artery embolization. Surgery if refractory.
Workup
CXR (first). CT chest if CXR abnormal or high risk. Bronchoscopy if malignancy suspected or source unclear. CTA if massive or PE suspected.
Non-Massive
CXR + symptom management. If high risk (smoker, > 40, recurrent, > 30 mL) → CT chest + bronchoscopy for tissue diagnosis.
DAH
Diffuse alveolar hemorrhage: bilateral GGO, dropping Hgb, hemoptysis. Causes: ANCA vasculitis, anti-GBM, SLE, drug-induced. Treat underlying cause + pulse steroids.
Bronchial Artery Embolization
IR procedure, definitive for ~90% of massive hemoptysis. Bronchial arteries (high-pressure) are the source in most non-PE hemoptysis. Can recur -may need repeat.
📄 One Pager
One Pager -Pneumonia
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
PNEUMONIA -AT A GLANCE
📋 Diagnose: See Overview
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
📄 One Pager
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.
🧪 Causes
Bronchitis (#1 overall), bronchiectasis, malignancy (smoker > 40), pneumonia, TB, PE, vasculitis (DAH), AVM. Non-massive: CXR → CT if abnormal or high-risk → bronchoscopy.
🚨 Massive Hemoptysis (> 500 mL/24h)
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.
⚠️ DAH -Diffuse Alveolar Hemorrhage
Bilateral GGO + hemoptysis + dropping Hgb. Causes: ANCA vasculitis, anti-GBM (Goodpasture), SLE, drug-induced. Treatment: pulse steroids + treat underlying cause. BAL: progressively bloodier aliquots.
💊 Key Drugs
BronchoscopyLocalization + intervention
BAEBronchial artery embolization (IR)
TXA1g IV (adjunct for bleeding)
Treat underlyingAntibiotics, anticoag for PE, immunosuppression for vasculitis
⚠️ Pitfalls
- Not positioning bleeding side down (protects good lung)
- Small ETT (need ≥ 8.0 to allow bronchoscopy through tube)
- Missing malignancy in smoker > 40 (always consider)
- Attributing to bronchitis without follow-up imaging in high-risk patients
RoundsRx · Pulmonology
ACCP Hemoptysis 2017 · Defined by Jean-Baptiste Review
PulmonologyChronic
COPD -Chronic Management
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).
🔍 Overview
Diagnosis
- Spirometry: post-bronchodilator FEV₁/FVC < 0.70 confirms airflow obstruction
- 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 ABE Groups (2023 Update)
The 2023 GOLD report simplified the old ABCD into ABE. 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
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). |
| LABA + LAMA GROUP B/E | Umeclidinium/vilanterol (Anoro Ellipta) Tiotropium/olodaterol (Stiolto) | Group B (symptomatic), Group E (exacerbator) | Dual bronchodilation = backbone of COPD therapy. Better than either alone for FEV₁, symptoms, and exacerbation reduction. |
| ICS (add-on) SELECTIVE USE | Fluticasone, budesonide (always in combination with LABA ± LAMA) | Only if eosinophils ≥ 300 or frequent exacerbations despite LABA+LAMA | ICS is NOT first-line in COPD (unlike asthma). Increases pneumonia risk TORCH, 2007. Use blood eosinophils to guide: ≥ 300 → add ICS. < 100 → avoid ICS. |
| Triple: ICS + LABA + LAMA ESCALATION | Fluticasone/umeclidinium/vilanterol (Trelegy Ellipta) | 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. |
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 risk TORCH, 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.
Monitoring -Pulmonary Nodule & Lung Cancer Screening
| Parameter | Frequency | Target / Action |
|---|---|---|
| Vitals | q4h floor, q1–2h ICU | Notify for significant deviations from baseline |
| Labs | Daily AM or PRN | Trend disease-specific markers (see Overview) |
| I&Os | Strict if volume-sensitive | UOP ≥ 0.5 mL/kg/hr |
| Clinical response | Each assessment | Symptoms improving? Functional status? Appetite? |
🧪 Workup
Workup -Pulmonary Nodule & Lung Cancer Screening
Workup for Pulmonary Nodule & Lung Cancer Screening: Targeted H&P → disease-specific labs → imaging as indicated → specialist consultation if needed.
- History: Onset, duration, severity, associated symptoms, prior episodes, medications
- Physical exam: Focused exam relevant to presentation
- Labs: CBC, BMP + disease-specific labs (see Overview tab)
- Imaging: As clinically indicated
💊 Medications
Medications -Pulmonary Nodule & Lung Cancer Screening
Medication details for Pulmonary Nodule & Lung Cancer Screening are in the Management tab with evidence-based dosing and trial citations. Check Drug Interactions and renal dosing before prescribing.
⚡ Summary
Summary
GOLD Classification
Spirometry: GOLD I-IV by FEV₁ %. Group A/B/E by symptoms + exacerbation history. Group E (≥ 2 exacerbations/year) = most aggressive treatment.
Inhaler Ladder
Group A: SABA PRN. Group B: LABA or LAMA. Group E: LAMA + LABA + ICS (triple therapy) if eos ≥ 300. If eos < 300: LAMA + LABA without ICS.
Exacerbation Rx
Prednisone 40 mg × 5 days + antibiotics (azithromycin or doxycycline) if purulent sputum + bronchodilators + O₂ target 88-92%.
LTOT
SpO₂ ≤ 88% or PaO₂ ≤ 55 at rest → O₂ ≥ 15h/day reduces mortality [NOTT, MRC]. Moderate desaturation (89-93%): no benefit LOTT, 2016.
Exacerbation Prevention
Triple therapy (ICS/LABA/LAMA), azithromycin 250 MWF, roflumilast (eos ≥ 300), pulmonary rehab, smoking cessation, vaccinations.
Vaccines
PCV20, flu (annual), COVID, RSV (≥ 60), Tdap. All reduce exacerbation-related hospitalization.
📄 One Pager
One Pager -Pulmonary Nodule & Lung Cancer Screening
Print this page (Ctrl/Cmd + P) for a complete reference card. All tab content prints together.
PULMONARY NODULE & LUNG CANCER SCREENING -AT A GLANCE
🧪 Workup: See Workup tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
⚡ Treat: See Management tab
💊 Drugs: See Medications tab
📈 Monitor: See Monitoring tab
📣 Present: See Rounds tab
⚡ Management
Management -COPD -Chronic Management
See the Management section above for the full treatment algorithm with evidence-based recommendations and trial citations.
📄 One Pager
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)
RoundsRx · Pulmonology
GOLD 2024 · NOTT 1980 · MRC 1981 · LOTT 2016
PulmonologyAcute + Chronic
Asthma
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 Assessment
| Severity | Features | PEF | Management |
|---|---|---|---|
| Mild-Moderate | Can speak in sentences, RR < 30, HR < 120, SpO₂ > 92% | > 50% predicted | Albuterol nebs + oral steroids. May discharge if responsive. |
Acute Treatment Protocol
Immediate
Albuterol 2.5–5 mg nebulized q20 min × 3 (or continuous 10–15 mg/hr for severe). Add ipratropium (Atrovent) 0.5 mg to first 3 nebs -reduces hospitalizations Rodrigo, 2005.
Within 1 hour
Systemic corticosteroids: prednisone 40–60 mg PO or methylprednisolone 125 mg IV. Give early -takes 4–6h to work. Rowe, 2001: steroids within first hour reduced hospitalizations.
If severe / no response
Magnesium sulfate 2g IV over 20 min (smooth muscle relaxation). Goodacre, 2013 (3Mg Trial): improved PEF in severe exacerbations. Epinephrine 0.3–0.5 mg IM if anaphylaxis component or imminent arrest.
Refractory / ICU
IV terbutaline (selective β₂ agonist). Ketamine 0.5–1 mg/kg IV (bronchodilator properties). Heliox (80:20 helium:oxygen -reduces work of breathing in severe obstruction). BiPAP -may avoid intubation. Intubation is LAST RESORT -asthma patients are extremely difficult to ventilate (air trapping, high airway pressures, dynamic hyperinflation).
Intubation in status asthmaticus is dangerous: post-intubation dynamic hyperinflation (breath stacking) → auto-PEEP → hemodynamic collapse. Settings: low RR (8–12), prolonged I:E ratio (1:4–1:5), permissive hypercapnia. If peri-arrest hypotension post-intubation → disconnect from vent for 30–60 sec to allow exhalation.
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.
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
💊 Chronic Stepwise Therapy (GINA 2023)
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).
| Step | Track 1 (Preferred) | Track 2 (Alternative) | Notes |
|---|---|---|---|
| Step 1 (Mild intermittent) | As-needed low-dose ICS-formoterol (e.g., budesonide-formoterol PRN) | Low-dose ICS whenever SABA used | No more SABA-only. SYGMA, 2018: PRN budesonide-formoterol was superior to SABA alone for severe exacerbation prevention. |
| Step 2 (Mild persistent) | As-needed low-dose ICS-formoterol | Daily low-dose ICS + SABA PRN | ICS reduces exacerbations, hospitalizations, and death from asthma. This is the foundation. |
| Step 3 (Moderate) | Low-dose ICS-formoterol maintenance + reliever (MART) | Low-dose ICS-LABA + SABA PRN | MART = Maintenance And Reliever Therapy (same inhaler for both). Reduces exacerbation risk. |
| Step 4 (Moderate-severe) | Medium-dose ICS-formoterol maintenance + reliever | Medium/high-dose ICS-LABA + SABA PRN | Consider adding LAMA (tiotropium) if uncontrolled. |
| 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 (anti-IgE), mepolizumab/benralizumab (anti-IL5), dupilumab (anti-IL4R), tezepelumab (anti-TSLP). | |
Asthma vs COPD -Key Differences
| Feature | Asthma | COPD |
|---|---|---|
| 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 |
🔍 Overview
Overview
Chronic inflammatory airway disease with reversible obstruction. ~8% adults. Variable wheeze/cough/dyspnea worse at night. Diagnosis: spirometry with reversibility (≥12% AND ≥200mL).
🧪 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
🚨 Management
Management
- Step 1: PRN low-dose ICS-formoterol
- Step 2: Daily low-dose ICS
- Step 3: Low-dose ICS/LABA
- Step 4: Medium/high ICS/LABA ± LAMA
- Step 5: Biologic by phenotype
Before escalating: check technique, adherence, triggers, comorbidities (GERD, sinusitis, VCD).
🔄 Updated Practice: Old teaching: step 1 asthma treatment is SABA PRN alone (albuterol as needed). Current practice: GINA 2019+ no longer recommends SABA-only treatment for ANY asthma severity. Even mild intermittent asthma should use as-needed low-dose ICS-formoterol (SYGMA 1 & 2 trials). SABA-only use without ICS increases the risk of severe exacerbations and death. The paradigm shift: every puff of a bronchodilator should come with an anti-inflammatory.
💊 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 strategy |
| Tiotropium Respimat | 2.5mcg 2 puffs daily | Inhaler | LAMA add-on Step 4-5 |
| Prednisone | 40-60mg × 5d | PO | Exacerbation -no taper |
| Mepolizumab | 100mg q4wk | SQ | Anti-IL-5 (eos asthma) |
| Dupilumab | 200-300mg q2wk | SQ | Anti-IL-4/13 |
📋 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. (4)
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 125 mg IV (or prednisone 60 mg PO if tolerating)
- 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)
- Post-stabilization: prednisone 40 mg x 5 days, restart ICS/LABA, check technique
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).
Key findings: Spirometry: FEV1 68% predicted, 14% improvement post-bronchodilator. FeNO 58 ppb (elevated, suggests eosinophilic inflammation). Blood eos 480/mcL.
Management:
- 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 or mepolizumab
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.
Key findings: HR 140, RR 8 (bradypneic — pre-arrest), SpO2 78%, GCS 10. ABG: pH 7.12, pCO2 85, pO2 52. Peak flow unmeasurable.
Management:
- Emergent RSI: ketamine 2 mg/kg (bronchodilator) + rocuronium 1.2 mg/kg
- 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 + IV methylprednisolone 125 mg q6h + consider 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
Step Therapy
Step 1: PRN low-dose ICS-formoterol. Step 2: daily low-dose ICS. Step 3: medium ICS/LABA. Step 4: high ICS/LABA. Step 5: add LAMA, biologic, or OCS.
Before Escalating
Check: inhaler technique (70-80% incorrect), adherence, trigger avoidance, comorbidities (GERD, sinusitis, VCD). Fix these first.
Biologics
High eos → mepolizumab, benralizumab. High IgE + allergic → omalizumab. Type 2 inflammation → dupilumab, tezepelumab.
Acute Exacerbation
Albuterol neb q20 min × 3, ipratropium, systemic steroids (prednisone 40-60 mg × 5 days). MgSO₄ 2g IV if severe. Assess peak flow.
Action Plan
Green (well): continue controller. Yellow (worsening): increase ICS, start OCS, use rescue. Red (emergency): call 911, albuterol, start OCS.
Asthma vs COPD
Asthma: reversible obstruction, normal DLCO, younger, atopic. COPD: fixed obstruction, low DLCO, older, smoking. ACO: features of both → treat with ICS + bronchodilators.
📄 One Pager
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)
- Not checking eos/FeNO before biologics
- Missing VCD (vocal cord dysfunction mimics asthma)
RoundsRx · Pulmonology
GINA 2024 · NAEPP EPR-3 · ATS/ERS Severe Asthma
Evidence Base
Landmark Trials
Key trials behind every recommendation in Rounds. Click any trial for full details.
⌕
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 ≥30 g/L) 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 IBW) reduce mortality in ARDS?
N=861 with ARDS on mechanical ventilation. Low tidal volume (6 mL/kg IBW, 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 IBW 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.
Landmark
Airway & Sedation
ABC Trial (Awakening & Breathing Coordination)
2008 · Lancet · Airway & Ventilator Management / Sedation
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
Cardiology — ACS & CAD
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
4S Trial (Scandinavian Simvastatin Survival Study)
1994 · Lancet · Cardiology / Lipids
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
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
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
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
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)
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
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
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.
CABG wins for complex disease
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
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 effective but more bleeding
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
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
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). No difference in fatal CHD/nonfatal MI. Chlorthalidone was superior for HF prevention. Conclusion: Largest antihypertensive trial ever. Reinforced thiazide-type diuretics as first-line — cheap, effective, and prevents heart failure.
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 sulphate 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
2024 · 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
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
2024 · JAMA · Infectious Disease / Nephrotoxicity
Does cefepime cause less AKI than pip-tazo when combined with vancomycin?
N=2,511 hospitalized adults receiving vancomycin. Pip-tazo + vancomycin had higher AKI (8.3% vs 4.4%) compared to cefepime + vancomycin. Conclusion: Prefer cefepime over pip-tazo when combining with vancomycin to reduce nephrotoxicity risk.
Positive -cefepime preferred with vanc
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 submassive PE?
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 submassive 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.
Positive — 63% MASH resolution + fibrosis improvement
ANDROMEDA-SHOCK-2
2025 · JAMA · Critical Care / Sepsis
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 for shock ≥4h; 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.
Guideline — antimicrobial stewardship + prehospital focus
TETON-2
2026 · NEJM · Pulmonary
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. | Emergent access, codes, coagulopathy (compressible site). |
IJ -Step-by-Step (Ultrasound-Guided)
Prep
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)
- Frequent ABG sampling (respiratory failure, vent management)
- Intra-aortic balloon pump monitoring
🩺 Paracentesis
Technique
Position
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
- Normal: 60–100 bpm. Bradycardia < 60. Tachycardia > 100.
Step 2 -Rhythm
- Regular vs irregular? (march out R-R intervals with calipers or paper)
- P waves present? Upright in II = sinus origin. Absent = Afib/junctional. Flutter waves (sawtooth) = Aflutter.
- P:QRS relationship? 1:1 = sinus. More P's than QRS = AV block. No relationship = complete heart block.
Step 3 -Axis
| Lead I | Lead aVF | Axis |
|---|---|---|
| ↑ | ↑ | Normal (−30° to +90°) |
| ↑ | ↓ | Left axis deviation (think: LAFB, LVH, inferior MI) |
| ↓ | ↑ | Right axis deviation (think: RVH, PE, LPFB, lateral MI) |
| ↓ | ↓ | Extreme/indeterminate (think: ventricular rhythm, lead misplacement) |
Step 4 -Intervals
| Interval | Normal | If Abnormal |
|---|---|---|
| PR | 120–200 ms (3–5 small boxes) | Long (> 200): 1st degree AV block. Short (< 120): WPW (look for delta wave), junctional rhythm. |
| QRS | < 120 ms (3 small boxes) | 120–150: incomplete BBB, IVCD. > 150: LBBB, RBBB. > 200: hyperkalemia, TCA OD, severe conduction disease. |
| QTc | M < 450 ms, F < 470 ms | > 500 ms: high risk for torsades de pointes. Causes: drugs (haloperidol, ondansetron, amiodarone, FQ), electrolytes (↓K, ↓Mg, ↓Ca), congenital LQTS. |
Step 5 -ST Segment & T Waves
- ST elevation: STEMI, pericarditis (diffuse + PR depression), Brugada, early repolarization, LV aneurysm
- ST depression: ischemia (demand or NSTEMI), digoxin ("scooped"), LVH strain pattern, reciprocal changes
- T wave inversion: ischemia, Wellens pattern (LAD critical stenosis), PE (right precordial), LVH strain, intracranial event (deep cerebral T waves)
- Peaked T waves: hyperkalemia (#1), early STEMI (hyperacute T waves), benign early repolarization
⚡ Must-Know Patterns
| Pattern | ECG Findings | Clinical Significance |
|---|---|---|
| Hyperkalemia progression | Peaked T waves → prolonged PR → loss of P waves → wide QRS → sine wave → VFib/asystole | Give calcium immediately if QRS widening. The most lethal ECG pattern you'll see. See Hyperkalemia. |
| STEMI | ST elevation ≥ 1 mm in ≥ 2 contiguous limb leads, or ≥ 2 mm in precordial leads. Reciprocal ST depression. See STEMI Criteria tab. | Cath lab activation. |
| De Winter T waves | Upsloping ST depression + peaked T waves in V1–V6. No ST elevation. | LAD STEMI-equivalent. Activate cath lab even without classic STE. |
| Wellens syndrome | Type A: biphasic T waves in V2–V3. Type B: deep symmetric T wave inversions in V2–V3. | Critical LAD stenosis. Patient may be pain-free when ECG obtained. Do NOT stress test → send to cath lab. |
| PE | Sinus tachycardia (#1), S1Q3T3 (not sensitive), right axis deviation, RBBB, right precordial T inversions (V1–V4), P pulmonale | ECG is often normal in PE. Most reliable sign: sinus tachycardia. |
| WPW | Short PR (< 120 ms) + delta wave (slurred QRS upstroke) + wide QRS | 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. |
❤️ STEMI Localization
| Territory | STE Leads | Reciprocal Δ | Coronary Artery | Complications |
|---|---|---|---|---|
| Anterior | V1–V4 | II, III, aVF | LAD | LV dysfunction, CHF, VT/VF, anterior wall aneurysm |
| Lateral | I, aVL, V5, V6 | III, aVF | LCx or diagonal | Mitral regurgitation (papillary muscle) |
| Inferior | II, III, aVF | I, aVL | RCA (85%) or LCx (15%) | 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.
RoundsRx Licensed Content - Unauthorized Use Prohibited
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.
RoundsRx Licensed Content - Unauthorized Use Prohibited⚡ Cardiac Arrest -ACLS
Shockable Rhythms: VFib / Pulseless VTach
CPR
High-quality CPR immediately. Rate 100–120/min, depth 2–2.4 inches, full chest recoil. Minimize interruptions (< 10 sec for rhythm checks). Rotate compressors q2 min.
Shock
Defibrillate as soon as possible. Biphasic: 200J first shock, escalate if needed. Resume CPR immediately after shock × 2 min before rhythm check.
Epinephrine
Epinephrine 1 mg IV q3–5 min (give after 2nd shock if VFib/pVT). Do NOT delay shocks for epi.
Antiarrhythmic
Amiodarone 300 mg IV bolus (after 3rd shock if refractory VFib/pVT). 2nd dose: 150 mg. Alternative: lidocaine 1–1.5 mg/kg then 0.5–0.75 mg/kg.
H's & T's
Find and treat the cause. See below.
Non-Shockable: PEA / Asystole
- CPR + Epinephrine 1 mg IV q3–5 min. No shock. No antiarrhythmic.
- Focus on finding and treating the cause -PEA/asystole rarely responds to CPR alone without correcting the underlying etiology.
- Asystole: confirm in ≥ 2 leads (rule out fine VFib). No atropine (removed from algorithm). No defibrillation.
H's and T's -Reversible Causes
PEA and asystole will NOT respond to CPR alone -you MUST find and fix the underlying cause. Run through H's and T's every 2-minute cycle.
| Cause | Clues (History & Exam) | Intervention |
|---|---|---|
| H's | ||
| Hypovolemia | Trauma, GI bleed (hematemesis, melena), ruptured AAA, ruptured ectopic. Flat neck veins, pale, bloody NG aspirate. | Aggressive IVF boluses. Activate massive transfusion protocol. Blood products 1:1:1. Surgical consult if hemorrhagic. |
| Hypoxia | Pre-arrest desaturation, cyanosis, COPD/asthma history, mucus plug, aspiration event, known difficult airway. | 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). |
| Tamponade (cardiac) | Beck's triad: JVD + hypotension + muffled heart sounds. Recent cardiac surgery, pericardial effusion on prior imaging, dialysis patient (uremic pericarditis), trauma, malignancy, post-MI (free wall rupture). | 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 (massive 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 → 12 mg | 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.
D -Disability
GCS, pupils, glucose (stat fingerstick -ALWAYS check). New focal deficit → stroke alert. Seizure → benzos (lorazepam 4 mg IV). AMS → consider naloxone 0.4 mg IV (opioid reversal).
E -Exposure/Environment
Expose the patient -look for rashes (anaphylaxis, meningococcemia), surgical sites, lines, drains, skin findings. Check temperature. Review meds + recent changes. What changed?
Common Rapid Response Triggers
| Trigger | First Steps | Think |
|---|---|---|
| Acute desaturation | O₂, check SpO₂ probe, auscultate, CXR, ABG | PE, mucus plug, PTX, flash pulm edema, pneumonia, aspiration |
| Acute hypotension | Passive leg raise (NOT Trendelenburg -no evidence), IVF bolus, HR check, 12-lead ECG | Sepsis, hemorrhage, PE, cardiogenic, anaphylaxis, adrenal crisis |
| Tachycardia | 12-lead ECG, BP, fluid status, pain assessment | SVT, Afib/RVR, PE, sepsis, hypovolemia, pain, anxiety, withdrawal |
| Acute AMS | Glucose, O₂, vitals, pupils, review meds | Hypoglycemia, opioids, stroke, seizure (postictal), sepsis, hypercarbia |
| Acute chest pain | 12-lead ECG within 10 min, troponin, vitals, O₂ | ACS, PE, dissection, PTX, pericarditis |
CoreNight Float
Cross-Cover Algorithms
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.
Workup
CBC (drop in Hgb?), BMP, lactate, 12-lead ECG. Blood cultures if febrile. Consider: bedside echo (tamponade? RV strain? empty LV?), CXR (PTX? widened mediastinum?).
Call senior if
Not responding to 2L IVF. Active hemorrhage. New arrhythmia. Concern for PE, tamponade, or tension PTX. Need for pressors.
Think SHOCK: Septic (warm, febrile), Hypovolemic (dry, bleeding), Obstructive (PE, tamponade, PTX), Cardiogenic (JVD, crackles, cold), Anaphylactic (rash, wheezing, new med/food).
📉 Desaturation (SpO₂ < 92%)
Assess
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.
Call senior if
Cr doubled from baseline. Anuria (< 50 mL/12h). Hyperkalemia (K⁺ > 6 + ECG changes). Volume overloaded + oliguric (may need emergent dialysis).
CoreQuick Reference
Electrolyte Replacement
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 | ~0.3 mEq/L per 10 mEq | 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 | ~0.6–1.0 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 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.
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.
CoreQuick Reference
Pain Management & Conversions
WHO pain ladder, PCA dosing, multimodal analgesia, equianalgesic 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)
• 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 (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)
• 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.
Adjuvant Analgesics -Add at ANY Step
| Drug | MOA | Dose | Best For | ⚠️ Side Effects |
|---|---|---|---|---|
| Gabapentin (Neurontin) | Calcium channel α2δ ligand -reduces excitatory neurotransmitter release | 100–300 mg PO TID, titrate to 900–3600 mg/day | Neuropathic pain (diabetic neuropathy, post-herpetic neuralgia, radiculopathy) | ⚠️ Sedation, dizziness, peripheral edema. Renally cleared -reduce dose in CKD. |
| Pregabalin (Lyrica) | Same as gabapentin -higher affinity, more predictable absorption | 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 | 30 mg PO daily × 1 week → 60 mg daily | Diabetic neuropathy, musculoskeletal pain, fibromyalgia | ⚠️ Nausea (take with food), serotonin syndrome risk with tramadol/other serotonergics. Do NOT stop abruptly. |
| Dexamethasone (Decadron) | Glucocorticoid -reduces peritumoral edema and inflammation | 4–8 mg IV/PO daily | Bone metastases, spinal cord compression, bowel obstruction, cerebral edema | ⚠️ Hyperglycemia, insomnia, GI upset, immunosuppression. Short-term use preferred. |
| Lidocaine patch (5%) | Sodium channel blockade -local anesthetic | 1–3 patches to painful area, 12h on / 12h off | Localized neuropathic pain, post-herpetic neuralgia, musculoskeletal | ⚠️ Minimal systemic absorption. Skin irritation at site. |
| Ketamine (low-dose) | NMDA receptor antagonist -blocks central sensitization | 0.1–0.3 mg/kg/hr IV infusion | Opioid-refractory pain, chronic pain crises, sickle cell VOC | ⚠️ Dissociation, hallucinations, nausea, ↑ secretions. Avoid in psychosis, elevated ICP. |
| Muscle relaxants | Various -central acting (tizanidine, cyclobenzaprine, baclofen) | Tizanidine 2–4 mg TID, Cyclobenzaprine 5–10 mg TID, Baclofen 5–10 mg TID | Musculoskeletal spasm, back pain | ⚠️ 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.
| Pain Type | Recommended Multimodal Regimen |
|---|---|
| Post-surgical | Scheduled APAP 1g q6h + ketorolac 15 mg IV q6h (≤ 5 days) + gabapentin 300 mg preop + opioid PRN. Consider regional/nerve block. |
| Neuropathic | 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%)
• 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) or Vocalization (extubated) | Tolerating vent / talking normally | Coughing but tolerating / sighing, moaning | Fighting vent, triggering alarms / crying out, sobbing |
| 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. | |
| Tramadol (Ultram) | N/A | ~100–150 mg ≈ morphine 10 mg PO | - | 4–6h | Weak opioid + SNRI. Seizure risk. Serotonin syndrome risk. Max 400 mg/day. |
| Methadone | 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× (highest) | 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. |
| Prednisone (Deltasone) / Prednisolone (Orapred) | 5 mg | 4× | 0.8× | Intermediate (12–36h) | Most commonly prescribed oral steroid. Prednisone is a prodrug (converted to prednisolone in liver -use prednisolone in liver failure). |
| 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). |
| Dexamethasone (Decadron) | 0.75 mg | 25× | 0 (none) | Long (36–54h) | Most potent. No mineralocorticoid → no fluid retention. Best for cerebral edema, croup, meningitis. Does NOT suppress cortisol assays (use for cosyntropin testing). Long half-life → harder to taper. |
| Fludrocortisone (Florinef) | N/A | 10× | 125× (pure mineralocorticoid) | Long | Used for mineralocorticoid replacement only (Addison disease -0.1 mg daily). Not used as anti-inflammatory. |
Quick Conversions
- Prednisone 40 mg PO = methylprednisolone 32 mg IV = dexamethasone 6 mg = hydrocortisone 160 mg
- Prednisone 5 mg = the classic "physiologic" equivalent dose
- ≥ 20 mg prednisone/day × ≥ 3 weeks = HPA axis suppression → needs taper
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 |
| D | Diagnosis | Admitting diagnosis (e.g., "acute decompensated heart failure," "community-acquired pneumonia") |
| C | Condition | Stable, guarded, critical |
| V | Vitals | Frequency (q4h floor, q1h ICU). Parameters to notify (HR > 130, SBP < 90, SpO₂ < 92%, T > 38.5, UOP < 30 mL/hr × 2h) |
| A | Allergies | Drug allergies + reaction type (rash vs anaphylaxis -this changes management) |
| N | Nursing | I&Os, daily weights (HF, CKD), fall precautions, aspiration precautions, wound care, restraint orders, fingerstick glucose schedule (AC+HS if diabetic), foley care |
| D | Diet | Regular, cardiac (< 2g Na), renal (low K⁺/PO₄), diabetic (carb-controlled), NPO (pre-procedure), clear liquids, pureed/thickened (dysphagia) |
| A | Activity | 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. |
| S | Special studies / consults | ECG, CXR, echo, CT. Consults: cardiology, GI, surgery, social work, palliative. |
| M | Medications | 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."
💧 Fluid Selection
Crystalloids
| Fluid | Na⁺ | Cl⁻ | K⁺ | Buffer | Osmolality | Use |
|---|---|---|---|---|---|---|
| NS (0.9% NaCl) | 154 | 154 | 0 | None | 308 | Volume resuscitation (default bolus fluid), hypernatremia correction, metabolic alkalosis (Cl⁻-responsive -NS provides chloride). Caution: large volumes → hyperchloremic metabolic acidosis. |
| LR (Lactated Ringer's) PREFERRED | 130 | 109 | 4 | Lactate 28 | 273 | 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. |
| ½NS (0.45% NaCl) | 77 | 77 | 0 | None | 154 | Maintenance fluid (with 20 mEq KCl/L = "D5 ½NS + 20 KCl"). Hypernatremia correction. Hypotonic -NOT for boluses. |
| D5NS | 154 | 154 | 0 | None | 560 | 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, 2004 ALBIOS, 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 | D5 ½NS + 20 KCl/L (standard) D5NS (if Na⁺ low or adrenal crisis) D5 ¼NS (pediatrics) | 4-2-1 rule: First 10 kg: 4 mL/kg/hr Next 10 kg: 2 mL/kg/hr Each additional kg: 1 mL/kg/hr (~75–125 mL/hr for adults) | ⚠️ NOT everyone gets maintenance fluids! • ✅ Give if: NPO + euvolemic • ❌ Do NOT give if: eating/drinking, HF, cirrhosis, SIADH, CKD/ESRD, volume overloaded, post-resuscitation • Hypotonic (½NS) because kidneys retain Na⁺ and excrete free water normally • Dextrose prevents starvation ketosis (~170 kcal/L) • Add KCl 20 mEq/L (daily K⁺ need ~40–60 mEq) • NOT for volume resuscitation -hypotonic fluids don't stay intravascular |
| 🔵 Replacement (Specific deficits) | Replace specific electrolyte or water deficits | D5W -free water (hypernatremia, DI) ½NS -mild hypernatremia 3% Hypertonic -severe hyponatremia NS -Cl⁻-responsive metabolic alkalosis | 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.
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). | Traumatic brain injury SAFE, 2004: increased mortality. |
| Albumin 25% | 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, 2008 6S, 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). |
| Pancreatitis | LR (preferred over NS -less SIRS, less AKI). |
| Salicylate (ASA) toxicity | D5W + NaHCO₃ drip (150 mEq in 1L D5W). Goal urine pH 7.5–8.0. Enhances renal excretion. |
| TCA overdose (wide QRS) | NaHCO₃ bolus (1–2 mEq/kg IV push), then bicarb drip. Give until QRS narrows. |
| Rhabdomyolysis | Aggressive LR + consider bicarb drip (goal urine pH > 6.5 to prevent myoglobin cast nephropathy). |
| Severe metabolic acidosis (pH < 7.1) | NaHCO₃ drip as bridge. Treat underlying cause. Not beneficial in DKA (insulin fixes it). |
| HF / volume overloaded | No fluids. Diurese. If needs meds → use smallest volume (hep-lock, concentrated drips). |
| Cirrhosis + SBP | Albumin (not crystalloid -albumin reduces HRS and mortality). |
📐 Rates & Formulas
Who Actually Needs Maintenance Fluids?
| ✅ Give Maintenance Fluids | ❌ Do NOT Give Maintenance Fluids |
|---|---|
| NPO (nothing by mouth) -surgery, intubated, bowel obstruction, severe vomiting | Eating and drinking normally -just saline-lock the IV |
| Euvolemic -not dehydrated, not overloaded | Heart failure -extra fluid worsens congestion |
| No IV fluid restriction | Cirrhosis with ascites -fluid restricted (1–1.5L/day) |
| Unable to match insensible losses orally | SIADH / hyponatremia -fluid restriction is first-line treatment |
| CKD/ESRD on dialysis -can't excrete the volume | |
| Volume overloaded for any reason -pulmonary edema, anasarca | |
| Post-resuscitation -once volume restored, STOP. Don't leave "NS at 125" running. |
⚠️ 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.
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.
Maintenance Rate -4-2-1 Rule
- First 10 kg: 4 mL/kg/hr
- Next 10 kg: 2 mL/kg/hr
- Each additional kg: 1 mL/kg/hr
- Example: 70 kg patient → (4×10) + (2×10) + (1×50) = 40 + 20 + 50 = 110 mL/hr
Free Water Deficit (for Hypernatremia)
FWD = TBW × (Na/140 − 1)
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. | D5W = 1000 mL free water/L | |
| Hypervolemic (rare -iatrogenic hypertonic saline, sodium bicarb excess) | D5W + furosemide -diuretic removes excess Na⁺ while D5W replaces free water | D5W = 1000 mL free water/L + furosemide excretes Na⁺-rich urine | |
⚠️ 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.
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
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
CBC Fishbone
Transfuse: Hgb < 7 (most) | < 8 (ACS) | Plt < 10K (prophylactic) | < 50K (procedure)
CMP = BMP + Hepatic Panel
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
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
🔬 CBC
| Lab | Normal | High | Low | Clinical Action |
|---|---|---|---|---|
| WBC | 4.5–11 K | Leukocytosis: infection (#1), steroids (demargination), stress, leukemia, medication | Leukopenia: sepsis (bad sign -WBC consumed), chemo, bone marrow failure, SLE, viral | Leukocytosis + fever → blood cultures + workup. Neutropenia (ANC < 500) + fever → cefepime within 60 min. |
| Hgb/Hct | M: 14–17 F: 12–16 | Polycythemia vera, dehydration (hemoconcentration), chronic hypoxia | Anemia: classify by MCV. Microcytic (iron def, thalassemia), normocytic (chronic disease, AKI, bleeding), macrocytic (B12/folate, EtOH, MDS) | Transfuse if Hgb < 7 (most patients) or < 8 (ACS). Reticulocyte count to assess production. |
| Platelets | 150–400 K | Reactive (infection, inflammation, iron deficiency, splenectomy). Essential thrombocythemia if > 450K persistent. | Thrombocytopenia: ↓ production (chemo, EtOH, MDS), ↑ destruction (ITP, TTP, HIT, DIC), sequestration (splenomegaly), dilutional (massive resuscitation) | If new drop → review meds (heparin → 4T score for HIT). < 50K → hold anticoagulation. < 10K → transfuse (unless TTP/HIT). |
🔬 BMP / CMP
| Lab | Normal | Key Abnormalities | Quick Action |
|---|---|---|---|
| Na⁺ | 136–145 | Low: see Hyponatremia. High: free water deficit (dehydration, DI, inadequate access to water). | Correct ≤ 8–10 mEq/L per 24h in either direction. |
| K⁺ | 3.5–5.0 | High: AKI, ACEi/ARB, spironolactone, rhabdo, hemolysis (pseudohyperK), acidosis. Low: diuretics, GI losses, renal wasting. | K⁺ > 6 + ECG changes → calcium first, then insulin/D50. See Hyperkalemia. Always check Mg. |
| HCO₃ / CO₂ | 22–28 | Low: metabolic acidosis (calculate AG). High: metabolic alkalosis or chronic respiratory acidosis compensation. | Low HCO₃ → calculate anion gap → if elevated, calculate delta-delta. See Acid-Base. |
| BUN / Cr | BUN 7–20 Cr 0.7–1.3 | ↑ BUN/Cr > 20:1: pre-renal (dehydration, HF, GI bleed). ↑ BUN + Cr proportionally: intrinsic renal (ATN). Cr trend matters more than absolute value. | Compare to baseline. Rising Cr → hold nephrotoxins (NSAIDs, ACEi, contrast), check volume status, UA, FENa. |
| Glucose | 70–100 (fasting) | High: DM, steroids, stress response, DKA. Low: insulin excess, sulfonylurea, liver failure, sepsis, adrenal insufficiency, alcohol. | < 70 → D50 1 amp IV + recheck in 15 min. > 300 → check ketones + anion gap (DKA?). |
| Calcium | 8.5–10.5 (total) 1.1–1.3 (ionized) | Always correct for albumin or check ionized. See Hypercalcemia. | High Ca → check PTH. Low iCa → check Mg, PO₄, PTH, vitamin D. |
🔬 Liver Function Tests
| Pattern | AST/ALT | Alk Phos / GGT | Bilirubin | Think |
|---|---|---|---|---|
| Hepatocellular | ↑↑↑ (AST/ALT > 10× ULN) | Mildly ↑ | Variable | Viral hepatitis, drug-induced (acetaminophen -check level + NAC), ischemic hepatitis ("shock liver"), autoimmune hepatitis, Wilson disease |
| Cholestatic | Mildly ↑ | ↑↑↑ | ↑↑ | 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. |
| Procalcitonin | < 0.1 ng/mL | < 0.25: bacterial infection unlikely. > 0.5: likely bacterial. Useful for: antibiotic de-escalation in pneumonia/sepsis (if procal drops > 80% → safe to stop abx). NOT reliable in: immunocompromised, post-surgery, burns, pancreatitis. |
| ESR | M: 0–22 F: 0–29 | 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. |
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.
| Category | High-Risk Drugs | Ward Relevance |
|---|---|---|
| Antiarrhythmics | Amiodarone (Cordarone), sotalol (Betapace), dofetilide (Tikosyn), procainamide (Pronestyl) | Amiodarone is the most commonly prescribed. Check QTc before loading. |
| Antibiotics | Fluoroquinolones (levofloxacin, moxifloxacin > cipro), azithromycin, TMP-SMX (rare) | Moxifloxacin has the highest QT risk among FQs. Azithro risk is lower but additive with other drugs. |
| Antifungals | Fluconazole (Diflucan), voriconazole (Vfend) | Fluconazole at higher doses (> 400 mg). Also inhibits CYP2C9/3A4 → increases levels of warfarin, phenytoin. |
| Antiemetics | Ondansetron (Zofran), droperidol | Ondansetron at doses > 16 mg IV. FDA warning. 4 mg IV is generally safe but still additive. Check QTc if combining with other QT drugs. |
| Antipsychotics | Haloperidol (Haldol) (especially IV), ziprasidone, chlorpromazine | 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. |
Treatment
- Stop all serotonergic agents
- Cyproheptadine 12 mg PO loading → 4 mg q6h (serotonin antagonist)
- Benzodiazepines for agitation and muscle rigidity
- Cooling if hyperthermic. Avoid paralysis (masks clonus -makes monitoring impossible).
- Most cases resolve within 24–72h after stopping the offending drug
⚠️ Key Drug Combinations to Watch
| Combination | Risk | What to Do |
|---|---|---|
| ACEi/ARB + K⁺-sparing diuretic + NSAID | "Triple whammy" → hyperkalemia + AKI | Avoid triple combination. If unavoidable → check K⁺ and Cr within 1 week. Stop NSAID if possible. |
| Warfarin + TMP-SMX | ↑↑ INR (TMP-SMX inhibits CYP2C9) | INR can double within 3–5 days. Check INR 3 days after starting TMP-SMX. Reduce warfarin dose empirically. |
| Warfarin + fluconazole | ↑↑ INR (fluconazole inhibits CYP2C9) | Same as above. Reduce warfarin dose by ~25–50%. Check INR frequently. |
| Warfarin + amiodarone | ↑ INR (CYP inhibition) -effect persists weeks after stopping amio | Reduce warfarin dose by 30–50% when starting amiodarone. Monitor INR weekly. |
| Statin + clarithromycin/erythromycin | Rhabdomyolysis (CYP3A4 inhibition → statin levels ↑↑) | Hold statin during macrolide course. Or use azithromycin (no CYP3A4 inhibition). |
| Colchicine (Colcrys) + clarithromycin | Fatal toxicity (CYP3A4 + P-gp inhibition → colchicine accumulates) | 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. |
| Allopurinol (Zyloprim) + azathioprine (Imuran) | Fatal myelosuppression (allopurinol blocks xanthine oxidase → azathioprine accumulates) | Reduce azathioprine dose by 75% if must co-administer. Or use mycophenolate instead. Monitor CBC closely. |
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.
🩸 Emergency Reversal
| Anticoagulant | Reversal Agent | Dose | Onset | Key Notes |
|---|---|---|---|---|
| Warfarin | 4-Factor PCC (Kcentra) LIFE-THREATENING | INR 2–4: 25 units/kg INR 4–6: 35 units/kg INR > 6: 50 units/kg | Minutes | 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 (Savaysa) | Andexanet alfa (Andexxa) | Low dose: 400 mg bolus → 4 mg/min × 2h High dose: 800 mg bolus → 8 mg/min × 2h | Minutes | Recombinant modified Factor Xa decoy. Very expensive (~$50,000/dose). Low dose if last DOAC dose > 8h ago or low-dose apixaban. High dose if within 8h or rivaroxaban. 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 bridging BRIDGE, 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. |
ToolCalculator
Insulin Calculator
Convert sliding scale usage into a proper basal-bolus regimen. Enter the patient's 24h sliding scale insulin usage and get a calculated basal-bolus prescription.
🧮 Sliding Scale → Basal-Bolus Converter
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.
📋 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.
🩻 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. |
| B -Bones & soft tissue | Ribs (fractures?), clavicles, spine, subcutaneous emphysema | Rib fractures → PTX? Flail chest (≥3 consecutive ribs, ≥2 places)? Lytic lesions (mets)? SubQ air → esophageal rupture, necrotizing infection. |
| C -Cardiac | Heart size, silhouette, mediastinum width | 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. |
Before interpreting: check patient name, date, PA vs AP (AP magnifies heart → can't assess cardiomegaly), rotation (spinous processes centered between clavicular heads), inspiration (≥ 9 posterior ribs = adequate), penetration (should barely see spine through cardiac silhouette).
🔍 Common CT Findings
| Finding | Think | Clinical Action |
|---|---|---|
| CT Head -hyperdense (white) | Acute blood (ICH, SDH, EDH, SAH) | SDH: crescent-shaped, crosses suture lines. EDH: lens-shaped, doesn't cross sutures. SAH: blood in sulci/cisterns → CTA for aneurysm. ICH: check INR, reverse anticoag. |
| CT Head -hypodense (dark) | Ischemic stroke (after 6–12h), chronic SDH, edema | Acute stroke may be normal on CT < 6h → loss of gray-white differentiation is earliest sign. MRI DWI is more sensitive early. |
| CTPA -filling defect in PA | Pulmonary embolism | Saddle PE (at bifurcation) → hemodynamically significant. RV/LV ratio > 1 → RV strain. Check troponin, BNP. |
| CT Chest -ground glass opacities (GGO) | PCP pneumonia (HIV), viral PNA (COVID, influenza), pulmonary edema, DAH, early ILD, drug toxicity | Bilateral diffuse GGO + HIV → check CD4, start TMP-SMX for PCP. Bilateral + ICU → ARDS. Peripheral/basal → UIP/IPF pattern. |
| CT Chest -tree-in-bud pattern | TB, atypical mycobacteria, aspiration | 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.
Tools
Medical Games
Gamified clinical reasoning to sharpen your diagnostic skills between shifts.
Available Games
🩺
Doctordle
Medical Wordle -guess the medical term in 6 tries. New word daily.
🔗 PLAY (EXTERNAL)
🚨
Full Code Medical
Interactive clinical case simulations -run codes, manage ICU patients, and practice real-time decision making.
🔗 PLAY (EXTERNAL)
🏥
Prognosis
Real-world clinical cases -diagnose and manage patients with interactive scenarios across all specialties.
🔗 PLAY (EXTERNAL)
Study Tool
🧠 Pimp Me
Random clinical questions from all topics. Test yourself before rounds. Click to reveal the answer.
Loading...
Loading question...
0 / 0
Workflow
✅ Shift Checklist
Start-of-shift and end-of-shift checklists. Resets daily. Check items off as you go.
0 / 0 done
☀️ Start of Shift
🌙 End of Shift
Quick Access
⭐ Favorites
Your bookmarked pages for one-tap access. Star any page from the ⭐ button in the header.
Portfolio
📊 Shift Tracker
Log admits, notes, and procedures per shift. Export for your residency portfolio.
📋 Shift Log
Admits
0
Notes Written
0
Procedures
0
📈 Shift History
Distribution
📱 QR Code Poster
Print this poster and tape it in the resident lounge, call rooms, and workrooms. One scan = instant access to RoundsRx.
CLINICAL REFERENCE
RoundsRx
BEDSIDE DECISION ENGINE
roundsrx.com
Free evidence-based clinical decision support.
Protocols · Antibiotics · Calculators · Presentations
Protocols · Antibiotics · Calculators · Presentations
Coverage
239 Clinical Topics
Rotations
15 Specialties
Study
938 Pimp Questions
Works
Offline · Mobile · Free
Built for internal medicine residents · Evidence-based with trial citations
Sepsis · DKA · ARDS · Heart Failure · Antibiotics · ECG · Code Blue · Calculators
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 24h, or ≥4 units pRBC in 1 hour with ongoing hemorrhage. Activate MTP when anticipating need for massive resuscitation.
| MTP Trigger | Details | |||||
|---|---|---|---|---|---|---|
| Scoring System | Criteria | Threshold |
|---|---|---|
| ABC Score | Penetrating mechanism (+1), SBP ≤ 90 (+1), HR ≥ 120 (+1), positive FAST (+1) | ≥ 2 activates MTP |
| Shock Index | HR / SBP | > 1.0 predicts need for MTP |
| Clinical Triggers | Obvious massive hemorrhage, hemodynamic instability unresponsive to 2L crystalloid | Clinical judgment |
| Quantitative | ≥ 4 units pRBC in 1 hour with ongoing bleeding, OR anticipated need for ≥ 10 units pRBC in 24h | Volume-based |
The Lethal Triad
Hypothermia + Acidosis + Coagulopathy form a self-perpetuating vicious cycle that drives mortality in hemorrhagic shock.
| Component | Mechanism | Prevention/Treatment |
|---|---|---|
| Hypothermia | Core temp < 35°C impairs coagulation enzyme kinetics, platelet function, and fibrinolysis | Warm all products via rapid infuser, forced-air warming blanket, warm OR/room, warm IV fluids. Target temp > 36°C |
| Acidosis | Hemorrhagic shock → tissue hypoperfusion → lactic acidosis. pH < 7.2 severely impairs clotting factor function | Restore perfusion with blood products (not crystalloid). Limit NS (hyperchloremic acidosis). Bicarb if pH < 7.1 |
| Coagulopathy | Dilutional (crystalloid), consumptive (ongoing hemorrhage), and dysfunction (hypothermia + acidosis impair cascade) | 1:1:1 balanced resuscitation, cryo for fibrinogen < 150, TXA, avoid excess crystalloid |
MTP Deactivation Criteria
- Surgical/interventional hemostasis achieved (source of bleeding controlled)
- Hemodynamically stable without vasopressors or ongoing blood product requirement
- Labs normalizing: lactate trending down, pH > 7.25, fibrinogen > 150, INR < 1.5
- No active hemorrhage on reassessment
- 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.
| 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
- Permissive hypotension: Target SBP 80–90 until surgical hemostasis (except TBI -MAP ≥ 80)
- Damage control resuscitation: Limit crystalloid. Avoid hypothermia, acidosis, coagulopathy ("lethal triad")
TEG/ROTEM Basics
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).
🧪 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.
When should you deactivate MTP?
Deactivate when: surgical hemostasis achieved, hemodynamically stable, labs normalizing (lactate down, pH > 7.25, fibrinogen > 150, INR < 1.5). Communicate with blood bank. Monitor for rebound coagulopathy 4–6h post-resuscitation.
Clinical Examples
📋 Case 1 — Trauma MTP Activation
Patient: 28M restrained driver, high-speed MVC. GCS 14, HR 132, BP 78/50, RR 24. FAST positive. Pelvis unstable.
Assessment: ABC Score = 3 (SBP ≤ 90, HR ≥ 120, FAST+). Shock Index 1.7. Activate MTP.
Management:
- MTP activated: O-pos pRBC (male), thawed plasma, platelets 1:1:1
- TXA 1g IV over 10 min (within 30 min of injury)
- Pelvic binder. Permissive hypotension: target SBP 80–90
- CaCl 1g IV after 4 units pRBC. Warm all products via rapid infuser
- After 8 units: TEG low MA (42), fibrinogen 120 → cryo 10u + platelet apheresis
- IR pelvic angioembolization. Lactate 8→4, pH 7.18→7.30
- MTP deactivated after 14u pRBC, 12 FFP, 2 plt, 20u cryo
Key lesson: Activate MTP early on clinical criteria. Use TEG to guide products once initial resuscitation underway.
📋 Case 2 — GI Bleed with Coagulopathy
Patient: 62M, cirrhosis (MELD 24), large-volume hematemesis. HR 128, BP 82/48, lactate 7.2. INR 2.8, plt 52, fibrinogen 88.
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)
- TXA 1g IV immediately (WOMAN, 2017)
- Uterotonics: oxytocin 40u/1L LR, methylergonovine 0.2mg IM, carboprost 0.25mg IM q15min, misoprostol 800mcg PR
- Bimanual uterine massage
- CaCl 1g after 4u. iCa 0.82 → repeat CaCl
- 6 pRBC, 6 FFP, 1 plt, 10u cryo (fibrinogen 102)
- 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
MTP Trigger
ABC score ≥ 2, Shock Index > 1, or clinical judgment. Do NOT wait for labs.
Ratio
1:1:1 pRBC:FFP:Platelets. Based on PROPPR trial. Goal = approximate whole blood.
TXA
1g IV over 10 min → 1g over 8h. Within 3 hours only (CRASH-2). Antifibrinolytic.
Calcium
1g CaCl per 4 units pRBC. Citrate chelates Ca²⁺ → cardiac arrest if untreated.
Lethal Triad
Hypothermia + acidosis + coagulopathy. Warm products, limit crystalloid, 1:1:1 ratio.
Labs
CBC, coags, fibrinogen, iCa, K⁺, ABG q30-60 min. TEG/ROTEM if available.
CriticalICU
Brain Death Evaluation
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 |
🚨 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
🧪 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 |
💊 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
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.
📋 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.
⚡ Summary
Prerequisites
Known cause, irreversibility, core temp ≥ 36°C, SBP ≥ 100, no CNS depressants, no NMB.
Clinical Exam
Absent brainstem reflexes: pupillary, corneal, oculocephalic, oculovestibular, gag, cough. Two exams required.
Apnea Test
PaCO₂ ≥ 60 or ↑ ≥ 20 with NO respiratory effort. Pre-oxygenate, O₂ insufflation during test.
Ancillary Tests
If clinical exam incomplete: cerebral angiography (gold standard), EEG, nuclear scan, TCD.
Common Complication
Diabetes insipidus -loss of ADH → polyuria, hypernatremia. Treat with DDAVP.
Documentation
Two exams by qualified physicians. Record exact times. Time of death = time of second exam completion.
CriticalICU
Targeted Temperature Management
Post-cardiac arrest neuroprotection via controlled hypothermia (32–36°C) for 24h. Prevents secondary neuronal injury from reperfusion. Initiate early after ROSC. Avoid fever aggressively.
🔍 Overview
Indications
| Indication | Target Temperature | Evidence |
|---|---|---|
| Cardiac arrest (shockable rhythm) | 32–36°C × 24h | TTM, 2013; TTM2, 2021 |
| Cardiac arrest (non-shockable) | 32–36°C × 24h | Weaker evidence but still recommended by AHA guidelines. HYPERION, 2019 showed 33°C improved neurologic outcome in non-shockable rhythm arrests. |
| Key principle | Avoid fever (> 37.7°C) | Fever after cardiac arrest strongly associated with worse neurologic outcomes |
TTM2 (2021) found no benefit of 33°C vs normothermia. The key takeaway: aggressive fever prevention is what matters most. Target ≤ 37.5°C at minimum.
Contraindications to TTM
| Absolute | Relative |
|---|---|
| Active non-compressible bleeding | Known terminal illness / DNR prior to arrest |
| Known "do not cool" directive | Coagulopathy (relative — correct and cool) |
| Refractory cardiogenic shock on maximal vasopressors | Active sepsis (may worsen immunosuppression) |
| Core temp already < 30°C (accidental hypothermia protocol instead) | Recent major surgery within 14 days |
Prognostication After TTM (72-Hour Rule)
Do NOT prognosticate before 72 hours after rewarming. Sedation, paralysis, and hypothermia confound the neurologic exam. Use multimodal assessment.
| Modality | Timing | Poor Prognosis Finding | FPR |
|---|---|---|---|
| Clinical exam | ≥ 72h post-rewarming | Absent pupillary + corneal reflexes bilaterally | ~0% (most specific) |
| SSEP (N20) | ≥ 24h post-rewarming | Bilaterally absent cortical N20 responses | ~0–1% |
| NSE | 48–72h post-arrest | > 33 μg/L at 48h (hemolysis-adjusted) | ~0% at very high levels |
| EEG | ≥ 24h post-rewarming | Burst-suppression or status epilepticus without reactivity | Low but not zero |
| Brain MRI (DWI) | 2–5 days post-arrest | Diffuse cortical/basal ganglia restriction on DWI | Low |
Multimodal approach required. No single test should be used alone. AHA recommends ≥ 2 concordant predictors of poor outcome before withdrawal of life-sustaining treatment. Sandroni, 2014
🚨 Management
Three Phases of TTM
| Phase | Duration | Details |
|---|---|---|
| Induction | ASAP after ROSC | Cold IV saline 30 mL/kg (NOT during CPR), surface/intravascular cooling device. Reach target temp within 4h. |
| Maintenance | 24 hours | Hold at target ± 0.5°C. Continuous temp monitoring (esophageal or bladder probe). |
| Rewarming | 0.25°C/hour | SLOW -rapid rewarming causes rebound cerebral edema, seizures, hemodynamic instability. Takes 12–16 hours. |
Rewarm SLOWLY -0.25°C/hour maximum. Rapid rewarming negates all benefit of TTM and causes rebound injury.
Shivering Management — BSAS Scale & Stepwise Approach
| BSAS Score | Description | Action |
|---|---|---|
| 0 | No shivering | Continue current regimen |
| 1 | Shivering localized to neck/thorax (palpation only) | Surface counter-warming (Bair Hugger to hands/feet/face) + acetaminophen 1g IV q6h + buspirone 30 mg PO/NG q8h |
| 2 | Intermittent shivering involving upper extremities | Add meperidine 25–50 mg IV q4h (unique anti-shivering opioid) + Mg target 3–4 mg/dL |
| 3 | Generalized shivering or sustained extremity shivering | Increase sedation: propofol 5–50 mcg/kg/min + fentanyl 25–100 mcg/h. Consider dexmedetomidine 0.2–1.5 mcg/kg/h |
| 4 (Refractory) | Generalized shivering despite above measures | Neuromuscular blockade — cisatracurium 1–3 mcg/kg/min. REQUIRES continuous EEG (NMB masks seizures) |
Meperidine is the only opioid that lowers the shivering threshold. It works via kappa-opioid receptor agonism. Use cautiously in renal failure (normeperidine accumulation → seizures). Buspirone works synergistically with meperidine.
RoundsRx Licensed Content - Unauthorized Use Prohibited🧪 Workup
- Continuous core temperature (esophageal or bladder probe -NOT rectal, NOT axillary)
- Continuous EEG monitoring (seizure detection)
- CBC, BMP, Mg, PO₄ q6h (electrolyte shifts during cooling/rewarming)
- Coagulation studies q12h
- Lactate trending
- CT head -rule out hemorrhagic cause
- ECG -Osborn waves (J waves) at < 32°C
💊 Medications
| Drug | Dose | Purpose |
|---|---|---|
| Propofol (Diprivan) | 5–50 mcg/kg/min IV | Sedation -prevents shivering. First-line. |
| Fentanyl (Sublimaze) | 25–100 mcg/h IV | Analgesia + anti-shivering |
| Cisatracurium (Nimbex) | 1–3 mcg/kg/min IV | NMB -last resort for refractory shivering. Masks seizures -need continuous EEG |
| Meperidine (Demerol) | 25–50 mg IV | Anti-shivering (lowers shivering threshold). Unique among opioids. |
| Buspirone (Buspar) | 30 mg PO/NG | Anti-shivering adjunct |
| Magnesium Sulfate | Target Mg 3–4 mg/dL | Raises shivering threshold, neuroprotective |
What is the current target temperature after cardiac arrest based on TTM2?
TTM2 (2021) found no benefit of 33°C hypothermia vs normothermia (≤37.5°C). The key finding: aggressive fever prevention is what matters. Current practice: target 32–36°C based on institutional protocol, but the most important thing is preventing fever (> 37.7°C), which is strongly associated with worse neurologic outcomes.
Why is shivering a major concern during TTM?
Shivering is the body's thermoregulatory response to cooling. It increases metabolic rate 2–5x, generates heat (counteracting cooling), increases oxygen consumption, raises ICP, and causes patient discomfort. The anti-shivering cascade: surface counter-warming → acetaminophen + buspirone + meperidine → propofol/fentanyl → paralysis (last resort, requires continuous EEG).
What electrolyte abnormalities occur during TTM?
During cooling: K⁺, Mg²⁺, PO₄ shift intracellularly → hypokalemia, hypomagnesemia, hypophosphatemia. Replace cautiously. During rewarming: These ions shift back out → rebound hyperkalemia (can be dangerous). This is why rewarming must be slow (0.25°C/hr) and electrolytes checked frequently.
When can you reliably prognosticate after cardiac arrest with TTM?
Wait at least 72 hours after rewarming (not 72h after arrest). Sedation, hypothermia, and paralysis confound neurologic exam. Use a multimodal approach: clinical exam (absent pupillary/corneal reflexes), SSEP (bilaterally absent N20), NSE (> 33 μg/L at 48h), EEG (unreactive burst-suppression), and brain MRI (diffuse DWI restriction). AHA recommends ≥ 2 concordant poor prognostic findings before withdrawing care.
What is the HYPERION trial and how does it affect TTM in non-shockable rhythms?
HYPERION (2019) randomized patients with cardiac arrest from non-shockable rhythms (PEA/asystole) to 33°C vs normothermia. Favorable neurologic outcome at 90 days was higher in the hypothermia group (10.2% vs 5.7%), though overall mortality was similar. This is the best evidence supporting TTM in non-shockable arrests, though the absolute benefit is modest.
Why is meperidine uniquely effective for shivering compared to other opioids?
Meperidine is the only opioid with significant kappa-opioid receptor agonism, which lowers the shivering threshold more than mu-agonism alone. It reduces the shivering threshold by ~2°C. Other opioids (fentanyl, morphine) provide some anti-shivering effect via mu-receptors but are far less effective. Caution: normeperidine (active metabolite) accumulates in renal failure and lowers the seizure threshold.
Why must you have continuous EEG when using neuromuscular blockade during TTM?
Neuromuscular blockade eliminates all visible motor manifestations of seizures. Post-cardiac arrest patients have a 10–35% incidence of seizures/status epilepticus, which dramatically worsens neurologic outcome if untreated. Without continuous EEG, non-convulsive status epilepticus goes undetected. The only way to diagnose seizures in a paralyzed patient is EEG. This is a critical safety requirement — never paralyze without monitoring.
What are Osborn (J) waves and when do they appear during TTM?
Osborn waves (J waves) are positive deflections at the J-point (junction of QRS and ST segment) that appear when core temperature drops below ~32°C. They are most prominent in leads II, V5-V6. They are a marker of hypothermia — not intrinsically dangerous — but their appearance signals you may be overcooling. Other ECG changes during TTM: bradycardia (expected, do NOT treat unless hemodynamically unstable), prolonged QT, and atrial fibrillation.
Clinical Examples
📋 Case 1 — VFib Arrest with TTM Protocol
Patient: 58M, witnessed VFib arrest at gym. Bystander CPR started within 2 minutes, AED shock x1 with ROSC after 8 minutes. Arrives intubated, GCS 3T (no eye opening, no motor response). BP 92/58 on norepinephrine 5 mcg/min. HR 62.
Initial management:
- TTM initiation: Arctic Sun surface cooling device applied. Target 33°C per institutional protocol. Cold NS 30 mL/kg IV bolus to accelerate induction.
- Reached target temp: 33°C within 3.5 hours (goal < 4h).
- Anti-shivering: BSAS 2 on arrival — started buspirone 30 mg NG q8h + meperidine 25 mg IV q4h PRN. Surface counter-warming (Bair Hugger to hands/face).
- Monitoring: Esophageal temp probe, continuous EEG, K⁺ 3.1 → replaced cautiously (do not over-replace — will rebound during rewarming).
Maintenance (24 hours): Temp stable 33 ± 0.3°C. No seizures on EEG. Hemodynamically stable with norepinephrine weaned off by hour 12.
Rewarming: Started at hour 24. Rate 0.25°C/hr. K⁺ checked q2h during rewarming — rose from 3.8 to 5.1 (held KCl). Reached 37°C at hour 40.
Outcome: Neurologic exam at 72h post-rewarming: pupillary reflexes present, localizing to pain. EEG reactive. NSE 18 μg/L. Extubated day 5. Discharged with CPC 1 (good cerebral performance).
Key lesson: Early TTM with proper anti-shivering management and slow rewarming. Monitor electrolytes closely — replace during cooling but anticipate rebound during rewarming.
📋 Case 2 — Non-Shockable Arrest Prognostication
Patient: 72F found unresponsive at home. EMS arrived after ~15 min downtime. Initial rhythm PEA → asystole. ROSC after 28 minutes of CPR with epinephrine x4. Arrives comatose, GCS 3T, fixed dilated pupils. Lactate 14.
TTM: Cooled to 36°C (fever prevention strategy) given non-shockable rhythm and prolonged downtime. Maintained for 24h. Slow rewarming to 37°C.
Prognostication timeline:
- Day 1–3: No prognostication. Sedation off at 48h. Allow 24h washout.
- 72h post-rewarming: Absent pupillary reflexes bilaterally. Absent corneal reflexes. No motor response (M1). GCS 3.
- SSEP (day 3): Bilaterally absent cortical N20 responses — FPR ~0%.
- NSE (48h): 87 μg/L (markedly elevated, > 33 cutoff). No hemolysis on sample.
- EEG (day 3): Burst-suppression pattern, not reactive to stimulation.
- Brain MRI (day 4): Diffuse cortical and basal ganglia DWI restriction — consistent with severe hypoxic-ischemic injury.
Assessment: ≥ 4 concordant predictors of poor neurologic outcome. Family meeting held with palliative care. Goals of care transitioned to comfort measures on day 5.
Key lesson: Multimodal prognostication is essential. Wait 72h post-rewarming. No single test is sufficient — but concordant absent SSEP N20 + elevated NSE + unreactive EEG + diffuse DWI restriction is highly reliable for poor outcome.
📋 Case 3 — Refractory Shivering Management
Patient: 45M, VFib arrest s/p PCI for STEMI. ROSC after 12 minutes. TTM initiated targeting 33°C. Problem: severe refractory shivering preventing cooling — temp stuck at 35.8°C after 2 hours despite Arctic Sun.
Stepwise anti-shivering management:
- Step 1 (BSAS 2): Surface counter-warming (Bair Hugger to face/hands) + acetaminophen 1g IV + buspirone 30 mg NG → BSAS dropped to 1 briefly but recurred to 3.
- Step 2 (BSAS 3): Added meperidine 50 mg IV. Magnesium bolus 4g IV, target Mg 3–4. Temp now 34.8°C but stalled.
- Step 3 (BSAS 3, persistent): Increased propofol to 40 mcg/kg/min + fentanyl 75 mcg/h. Temp reached 34.2°C but still not at target after 3.5 hours.
- Step 4 (BSAS 4, refractory): Started cisatracurium 1.5 mcg/kg/min. Continuous EEG confirmed before paralysis initiated. Train-of-four monitoring q4h (target 1–2/4 twitches).
Result: Reached 33°C within 30 minutes of paralysis initiation. Maintained at 33 ± 0.2°C for 24h. Cisatracurium weaned during rewarming phase. EEG showed no seizure activity throughout.
Key lesson: Follow the stepwise anti-shivering cascade — don’t jump to paralysis. But when shivering is truly refractory and preventing target achievement, NMB is necessary. The non-negotiable requirement: continuous EEG must be running before you start NMB.
📋 On Rounds
Pimp Questions
What is the current target temperature after cardiac arrest based on TTM2?
TTM2 (2021) found no benefit of 33°C hypothermia vs normothermia (≤37.5°C). The key finding: aggressive fever prevention is what matters. Current practice: target 32–36°C based on institutional protocol, but the most important thing is preventing fever (> 37.7°C), which is strongly associated with worse neurologic outcomes.
Why is shivering a major concern during TTM?
Shivering is the body's thermoregulatory response to cooling. It increases metabolic rate 2–5x, generates heat (counteracting cooling), increases oxygen consumption, raises ICP, and causes patient discomfort. The anti-shivering cascade: surface counter-warming → acetaminophen + buspirone + meperidine → propofol/fentanyl → paralysis (last resort, requires continuous EEG).
What electrolyte abnormalities occur during TTM?
During cooling: K⁺, Mg²⁺, PO₄ shift intracellularly → hypokalemia, hypomagnesemia, hypophosphatemia. Replace cautiously. During rewarming: These ions shift back out → rebound hyperkalemia (can be dangerous). This is why rewarming must be slow (0.25°C/hr) and electrolytes checked frequently.
When can you reliably prognosticate after cardiac arrest with TTM?
Wait at least 72 hours after rewarming (not 72h after arrest). Sedation, hypothermia, and paralysis confound neurologic exam. Use a multimodal approach: clinical exam (absent pupillary/corneal reflexes), SSEP (bilaterally absent N20), NSE (> 33 μg/L at 48h), EEG (unreactive burst-suppression), and brain MRI (diffuse DWI restriction). AHA recommends ≥ 2 concordant poor prognostic findings before withdrawing care.
What is the HYPERION trial and how does it affect TTM in non-shockable rhythms?
HYPERION (2019) randomized patients with cardiac arrest from non-shockable rhythms (PEA/asystole) to 33°C vs normothermia. Favorable neurologic outcome at 90 days was higher in the hypothermia group (10.2% vs 5.7%), though overall mortality was similar. This is the best evidence supporting TTM in non-shockable arrests, though the absolute benefit is modest.
Why is meperidine uniquely effective for shivering compared to other opioids?
Meperidine is the only opioid with significant kappa-opioid receptor agonism, which lowers the shivering threshold more than mu-agonism alone. It reduces the shivering threshold by ~2°C. Other opioids (fentanyl, morphine) provide some anti-shivering effect via mu-receptors but are far less effective. Caution: normeperidine (active metabolite) accumulates in renal failure and lowers the seizure threshold.
Why must you have continuous EEG when using neuromuscular blockade during TTM?
Neuromuscular blockade eliminates all visible motor manifestations of seizures. Post-cardiac arrest patients have a 10–35% incidence of seizures/status epilepticus, which dramatically worsens neurologic outcome if untreated. Without continuous EEG, non-convulsive status epilepticus goes undetected. The only way to diagnose seizures in a paralyzed patient is EEG. This is a critical safety requirement — never paralyze without monitoring.
What are Osborn (J) waves and when do they appear during TTM?
Osborn waves (J waves) are positive deflections at the J-point (junction of QRS and ST segment) that appear when core temperature drops below ~32°C. They are most prominent in leads II, V5-V6. They are a marker of hypothermia — not intrinsically dangerous — but their appearance signals you may be overcooling. Other ECG changes during TTM: bradycardia (expected, do NOT treat unless hemodynamically unstable), prolonged QT, and atrial fibrillation.
Clinical Examples
📋 Case 1 — VFib Arrest with TTM Protocol
Patient: 58M, witnessed VFib arrest at gym. Bystander CPR started within 2 minutes, AED shock x1 with ROSC after 8 minutes. Arrives intubated, GCS 3T (no eye opening, no motor response). BP 92/58 on norepinephrine 5 mcg/min. HR 62.
Initial management:
- TTM initiation: Arctic Sun surface cooling device applied. Target 33°C per institutional protocol. Cold NS 30 mL/kg IV bolus to accelerate induction.
- Reached target temp: 33°C within 3.5 hours (goal < 4h).
- Anti-shivering: BSAS 2 on arrival — started buspirone 30 mg NG q8h + meperidine 25 mg IV q4h PRN. Surface counter-warming (Bair Hugger to hands/face).
- Monitoring: Esophageal temp probe, continuous EEG, K⁺ 3.1 → replaced cautiously (do not over-replace — will rebound during rewarming).
Maintenance (24 hours): Temp stable 33 ± 0.3°C. No seizures on EEG. Hemodynamically stable with norepinephrine weaned off by hour 12.
Rewarming: Started at hour 24. Rate 0.25°C/hr. K⁺ checked q2h during rewarming — rose from 3.8 to 5.1 (held KCl). Reached 37°C at hour 40.
Outcome: Neurologic exam at 72h post-rewarming: pupillary reflexes present, localizing to pain. EEG reactive. NSE 18 μg/L. Extubated day 5. Discharged with CPC 1 (good cerebral performance).
Key lesson: Early TTM with proper anti-shivering management and slow rewarming. Monitor electrolytes closely — replace during cooling but anticipate rebound during rewarming.
📋 Case 2 — Non-Shockable Arrest Prognostication
Patient: 72F found unresponsive at home. EMS arrived after ~15 min downtime. Initial rhythm PEA → asystole. ROSC after 28 minutes of CPR with epinephrine x4. Arrives comatose, GCS 3T, fixed dilated pupils. Lactate 14.
TTM: Cooled to 36°C (fever prevention strategy) given non-shockable rhythm and prolonged downtime. Maintained for 24h. Slow rewarming to 37°C.
Prognostication timeline:
- Day 1–3: No prognostication. Sedation off at 48h. Allow 24h washout.
- 72h post-rewarming: Absent pupillary reflexes bilaterally. Absent corneal reflexes. No motor response (M1). GCS 3.
- SSEP (day 3): Bilaterally absent cortical N20 responses — FPR ~0%.
- NSE (48h): 87 μg/L (markedly elevated, > 33 cutoff). No hemolysis on sample.
- EEG (day 3): Burst-suppression pattern, not reactive to stimulation.
- Brain MRI (day 4): Diffuse cortical and basal ganglia DWI restriction — consistent with severe hypoxic-ischemic injury.
Assessment: ≥ 4 concordant predictors of poor neurologic outcome. Family meeting held with palliative care. Goals of care transitioned to comfort measures on day 5.
Key lesson: Multimodal prognostication is essential. Wait 72h post-rewarming. No single test is sufficient — but concordant absent SSEP N20 + elevated NSE + unreactive EEG + diffuse DWI restriction is highly reliable for poor outcome.
📋 Case 3 — Refractory Shivering Management
Patient: 45M, VFib arrest s/p PCI for STEMI. ROSC after 12 minutes. TTM initiated targeting 33°C. Problem: severe refractory shivering preventing cooling — temp stuck at 35.8°C after 2 hours despite Arctic Sun.
Stepwise anti-shivering management:
- Step 1 (BSAS 2): Surface counter-warming (Bair Hugger to face/hands) + acetaminophen 1g IV + buspirone 30 mg NG → BSAS dropped to 1 briefly but recurred to 3.
- Step 2 (BSAS 3): Added meperidine 50 mg IV. Magnesium bolus 4g IV, target Mg 3–4. Temp now 34.8°C but stalled.
- Step 3 (BSAS 3, persistent): Increased propofol to 40 mcg/kg/min + fentanyl 75 mcg/h. Temp reached 34.2°C but still not at target after 3.5 hours.
- Step 4 (BSAS 4, refractory): Started cisatracurium 1.5 mcg/kg/min. Continuous EEG confirmed before paralysis initiated. Train-of-four monitoring q4h (target 1–2/4 twitches).
Result: Reached 33°C within 30 minutes of paralysis initiation. Maintained at 33 ± 0.2°C for 24h. Cisatracurium weaned during rewarming phase. EEG showed no seizure activity throughout.
Key lesson: Follow the stepwise anti-shivering cascade — don’t jump to paralysis. But when shivering is truly refractory and preventing target achievement, NMB is necessary. The non-negotiable requirement: continuous EEG must be running before you start NMB.
⚡ Summary
Indication
Comatose post-cardiac arrest (shockable or non-shockable). Start ASAP after ROSC.
Target
32–36°C × 24h. TTM2 suggests ≤37.5°C may suffice. AVOID FEVER -this is the key.
Rewarming
0.25°C/hour. SLOW. Rapid rewarming → rebound cerebral edema, seizures, hyperkalemia.
Shivering
Buspirone + meperidine → propofol/fentanyl → NMB (needs continuous EEG if paralyzed).
Electrolytes
K⁺/Mg/PO₄ shift in during cooling, shift out during rewarming. Monitor q4-6h.
Monitoring
Core temp (esophageal/bladder), continuous EEG, K⁺ q4h, glucose q1-4h, BSAS q1h.
EmergentCardiology
Cardiac Tamponade
Pericardial fluid compresses chambers → impaired filling → obstructive shock. Beck's triad: hypotension, JVD, muffled heart sounds. Echo-guided pericardiocentesis is lifesaving.
🔍 Overview
Pathophysiology
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 |
| Uremia | CKD/ESRD -hemorrhagic pericarditis |
| Iatrogenic | Post-cardiac surgery, catheterization, pacemaker insertion |
| Trauma | Penetrating chest injury, aortic dissection |
| Autoimmune | SLE, RA, scleroderma |
Beck's Triad: Hypotension + JVD + muffled heart sounds. Present in only ~30% of cases. Do NOT rely on complete triad -echo is the diagnostic tool.
🚨 Management
Emergent Management
- IV fluids -aggressive volume resuscitation to maintain preload (bridge to pericardiocentesis)
- AVOID diuretics, nitrates, positive pressure ventilation (all reduce preload → cardiovascular collapse)
- 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.
🧪 Workup
Diagnosis
- Echocardiography -gold standard. RA/RV diastolic collapse, IVC plethora, respiratory variation in mitral/tricuspid inflow
- ECG -low voltage, electrical alternans (beat-to-beat QRS amplitude variation = swinging heart)
- CXR -"water bottle" heart silhouette
- Pulsus paradoxus -SBP drop > 10 mmHg with inspiration
Echocardiographic Findings in Tamponade
| Finding | Description | Significance |
|---|---|---|
| RA collapse (systole) | Inward motion of RA free wall during ventricular systole | Most sensitive early sign (~85% sensitivity) |
| RV diastolic collapse | Inward motion of RV free wall during early diastole | Most specific finding (~90% specificity) |
| IVC plethora | Dilated IVC >2.1 cm with <50% inspiratory collapse | Elevated RA pressure; absence argues against tamponade |
| Respiratory variation | >25% variation in mitral inflow E velocity; >40% in tricuspid inflow | Reflects ventricular interdependence |
| Swinging heart | Heart oscillates within large effusion | Correlates with electrical alternans on ECG |
Pulsus Paradoxus — Detailed Mechanism
Pulsus paradoxus is an exaggeration of normal physiology. Normal inspiration: negative intrathoracic pressure → ↑ venous return to RV → slight RV expansion → slight leftward septal shift → minor ↓ LV filling → SBP drops 5–10 mmHg. In tamponade, the rigid pericardium constrains total cardiac volume. RV expansion during inspiration directly compresses the LV (ventricular interdependence) → marked ↓ LV stroke volume → SBP drops >10 mmHg.
How to measure: Inflate BP cuff above systolic. Slowly deflate. First Korotkoff sound heard only during expiration = Phase 1 pressure. Continue deflating until heard throughout cycle = Phase 2 pressure. Pulsus paradoxus = Phase 1 − Phase 2. >10 mmHg = positive.
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 |
| Send fluid | Cell count, protein/LDH, glucose, Gram stain, culture, cytology, ADA (if TB concern) |
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 |
| AVOID | Diuretics, nitrates, β-blockers, positive pressure ventilation |
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.
Vitals: HR 118, BP 88/62, RR 24, SpO2 93%. Pulsus paradoxus 18 mmHg.
Exam: JVD, muffled heart sounds, clear lungs (no pulmonary edema despite dyspnea — classic for tamponade vs CHF).
ECG: Low voltage, sinus tachycardia, electrical alternans.
Echo: Large circumferential effusion, RA systolic collapse, RV diastolic collapse, IVC plethora with no respiratory variation.
Management:
- IV NS 500 mL bolus as bridge
- Emergent echo-guided pericardiocentesis — 850 mL hemorrhagic fluid drained
- Pigtail catheter left in place for ongoing drainage
- Cytology: malignant cells consistent with breast adenocarcinoma
- Interventional oncology consulted for pericardial window given high reaccumulation risk
Teaching point: Malignant effusions are the #1 cause of tamponade in cancer patients. Clear lungs + JVD + hypotension = think tamponade, not CHF.
📋 Case 2 — Uremic Pericarditis
Patient: 64M with ESRD on hemodialysis (missed last 3 sessions) presenting with pleuritic chest pain, fever 38.2°C, and progressive dyspnea.
Vitals: HR 110, BP 92/58, RR 22. Pulsus paradoxus 14 mmHg.
Exam: Pericardial friction rub heard in 3 positions. JVD present. Bilateral lower extremity edema.
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.
📋 On Rounds
Pimp Questions
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.
Vitals: HR 118, BP 88/62, RR 24, SpO2 93%. Pulsus paradoxus 18 mmHg.
Exam: JVD, muffled heart sounds, clear lungs (no pulmonary edema despite dyspnea — classic for tamponade vs CHF).
ECG: Low voltage, sinus tachycardia, electrical alternans.
Echo: Large circumferential effusion, RA systolic collapse, RV diastolic collapse, IVC plethora with no respiratory variation.
Management:
- IV NS 500 mL bolus as bridge
- Emergent echo-guided pericardiocentesis — 850 mL hemorrhagic fluid drained
- Pigtail catheter left in place for ongoing drainage
- Cytology: malignant cells consistent with breast adenocarcinoma
- Interventional oncology consulted for pericardial window given high reaccumulation risk
Teaching point: Malignant effusions are the #1 cause of tamponade in cancer patients. Clear lungs + JVD + hypotension = think tamponade, not CHF.
📋 Case 2 — Uremic Pericarditis
Patient: 64M with ESRD on hemodialysis (missed last 3 sessions) presenting with pleuritic chest pain, fever 38.2°C, and progressive dyspnea.
Vitals: HR 110, BP 92/58, RR 22. Pulsus paradoxus 14 mmHg.
Exam: Pericardial friction rub heard in 3 positions. JVD present. Bilateral lower extremity edema.
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
Pathophys
Pericardial fluid → impaired diastolic filling → obstructive shock. Rate > volume.
Beck's Triad
Hypotension + JVD + muffled heart sounds. Only ~30% have all three. Use echo.
Echo Findings
RA systolic collapse, RV diastolic collapse, IVC plethora, respiratory variation.
Treatment
Pericardiocentesis (echo-guided). IV fluids as bridge. AVOID diuretics/PPV.
Avoid
Diuretics, nitrates, β-blockers, PPV -all reduce preload → collapse.
ECG
Low voltage, electrical alternans. Pulsus paradoxus > 10 mmHg.
High-YieldCardiology
Pulmonary Hypertension
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.
🔍 Overview
WHO Classification
| Group | Category | Examples |
|---|---|---|
| 1 | Pulmonary Arterial HTN (PAH) | Idiopathic, heritable, CTD-associated (scleroderma), HIV, portopulmonary, drugs |
| 2 | Left heart disease | 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)
PAH-Specific Drug Classes
| Pathway | Drugs | Notes |
|---|---|---|
| Endothelin receptor antagonists | Bosentan (Tracleer), Ambrisentan (Letairis), Macitentan (Opsumit) | Check LFTs monthly (hepatotoxicity). Teratogenic. |
| PDE-5 inhibitors | Sildenafil (Revatio), Tadalafil (Adcirca) | ↑ cGMP → pulm vasodilation. Avoid with nitrates. |
| Prostacyclin pathway | Epoprostenol (Flolan), Treprostinil (Remodulin), Iloprost (Ventavis) | 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.
PAH-Specific Therapy — Comprehensive Table
| Drug Class | Mechanism | Drugs | Route | Key Side Effects | Special Notes |
|---|---|---|---|---|---|
| Endothelin Receptor Antagonists (ERA) | Block ET-1 → reduce vasoconstriction + proliferation | Ambrisentan, Bosentan, Macitentan | PO | Hepatotoxicity (bosentan), peripheral edema, anemia | Teratogenic. Monthly LFTs for bosentan. SERAPHIN, NEJM 2013 |
| PDE-5 Inhibitors | ↑ cGMP → pulmonary vasodilation | Sildenafil, Tadalafil | PO | Headache, flushing, hypotension | Avoid with nitrates. Do NOT combine with riociguat |
| sGC Stimulator | ↑ cGMP (NO-independent) | Riociguat | PO | Hypotension, dizziness | For PAH or inoperable CTEPH. Contraindicated with PDE-5i. PATENT-1, NEJM 2013 |
| Prostacyclin Analogues | Vasodilation + antiproliferative + antiplatelet | Epoprostenol, Treprostinil, Iloprost | IV, SC, inhaled | Jaw pain, diarrhea, flushing, line sepsis (IV) | Epoprostenol = most potent, continuous IV. Never stop abruptly. Half-life 3-5 min |
| IP Receptor Agonist | Selective prostacyclin receptor agonist | Selexipag | PO | Headache, jaw pain, diarrhea, nausea | Oral alternative to parenteral prostacyclins. GRIPHON, NEJM 2015 |
| Calcium Channel Blockers | Vasodilation (for vasoreactive patients ONLY) | Nifedipine, Diltiazem, Amlodipine | PO | Hypotension, edema, bradycardia (diltiazem) | ONLY for positive vasoreactivity test (~5-10% of IPAH). NOT verapamil |
🧪 Workup
- TTE -RV dilation/dysfunction, TR jet velocity, RVSP estimate, RA pressure
- Right heart catheterization -diagnostic gold standard. mPAP ≥ 20 mmHg, PCWP, CO, PVR
- 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. |
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?
Right heart catheterization. Pre-capillary (Groups 1,3,4,5): mPAP ≥ 20, PCWP ≤ 15, PVR ≥ 3 Wood units. Post-capillary (Group 2): mPAP ≥ 20, PCWP > 15. Combined: PCWP > 15 AND PVR ≥ 3 (out-of-proportion 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).
- V/Q scan: Normal perfusion (excludes CTEPH).
- RHC: mPAP 48 mmHg, PAWP 12 mmHg, PVR 8.5 WU, CI 2.1 L/min/m², RAP 12 mmHg, SvO2 58%.
- 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.
- Labs: BNP 320, Cr 1.4, HbA1c 7.8.
- RHC: mPAP 38 mmHg, PAWP 22 mmHg, PVR 2.8 WU, CI 2.4 L/min/m².
Assessment: Combined pre- and post-capillary PH (CpcPH) — Group 2. PAWP 22 (>15) confirms post-capillary component. PVR 2.8 (>2 WU) indicates additional pre-capillary vascular remodeling.
Management:
- 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.
Labs: BNP 2,400 (baseline ~400), lactate 3.8, WBC 18k, blood cultures drawn. Cr 1.8 (baseline 0.9).
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.
📋 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?
Right heart catheterization. Pre-capillary (Groups 1,3,4,5): mPAP ≥ 20, PCWP ≤ 15, PVR ≥ 3 Wood units. Post-capillary (Group 2): mPAP ≥ 20, PCWP > 15. Combined: PCWP > 15 AND PVR ≥ 3 (out-of-proportion 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).
- V/Q scan: Normal perfusion (excludes CTEPH).
- RHC: mPAP 48 mmHg, PAWP 12 mmHg, PVR 8.5 WU, CI 2.1 L/min/m², RAP 12 mmHg, SvO2 58%.
- 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.
- Labs: BNP 320, Cr 1.4, HbA1c 7.8.
- RHC: mPAP 38 mmHg, PAWP 22 mmHg, PVR 2.8 WU, CI 2.4 L/min/m².
Assessment: Combined pre- and post-capillary PH (CpcPH) — Group 2. PAWP 22 (>15) confirms post-capillary component. PVR 2.8 (>2 WU) indicates additional pre-capillary vascular remodeling.
Management:
- 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.
Labs: BNP 2,400 (baseline ~400), lactate 3.8, WBC 18k, blood cultures drawn. Cr 1.8 (baseline 0.9).
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
Definition
mPAP ≥ 20 mmHg by RHC. Group 2 (left heart disease) is most common overall.
Diagnosis
RHC is gold standard. TTE screens. V/Q scan for CTEPH. Vasoreactivity testing for CCB trial.
Group 1 Therapy
ERAs + PDE-5i ± prostacyclins. Combination therapy based on risk stratification.
Key Avoid
PAH drugs in Group 2 (worsens edema). Never stop epoprostenol abruptly (rebound crisis).
RV Management
Avoid volume overload. Careful diuresis. Maintain preload. Avoid systemic vasodilators.
Monitoring
6MWD, BNP, echo, WHO functional class. LFTs monthly on ERAs.
High-YieldCardiology
Stable Angina & Chronic CAD
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 |
| Anatomy | Single-vessel disease, normal EF | Left main, 3-vessel disease, ↓ EF |
| Symptoms | CCS Class I–II | CCS Class III–IV despite GDMT |
🚨 Management
Medical Therapy (GDMT)
- Anti-anginal: β-blockers (1st line) → CCBs (if β-blocker contraindicated) → long-acting nitrates → ranolazine
- Anti-ischemic risk reduction: Aspirin 81 mg daily, high-intensity statin, ACEi/ARB (especially if DM, HTN, HFrEF)
- Lifestyle: Smoking cessation (#1 modifiable risk factor), exercise, weight loss, Mediterranean diet, BP < 130/80, A1c < 7%
Revascularization
Based on ISCHEMIA, 2020 -no mortality benefit of routine revascularization over GDMT in stable CAD.
- PCI -symptom relief. No mortality benefit in stable CAD (COURAGE, ISCHEMIA).
- CABG -survival benefit in left main disease, 3-vessel disease with ↓ EF, or diabetes with multi-vessel disease
🧪 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.
- Coronary CT angiography -anatomic assessment, calcium scoring
- Cardiac catheterization -if high-risk features on non-invasive testing
- Lipid panel, HbA1c, BMP, TSH
- Echo -baseline LV function
💊 Medications
| Drug | Dose | Role | Key Notes |
|---|---|---|---|
| Metoprolol Succinate (Toprol XL) | 25–200 mg daily | 1st line anti-anginal | ↓ HR → ↓ myocardial O₂ demand. Target HR 55–60. |
| Amlodipine (Norvasc) | 5–10 mg daily | 2nd line / add-on | Long-acting DHP CCB. Use if β-blocker contraindicated or vasospastic angina. |
| Isosorbide Mononitrate (Imdur) | 30–120 mg daily | Add-on anti-anginal | 10–14h nitrate-free interval required to prevent tolerance. |
| Ranolazine (Ranexa) | 500–1000 mg BID | Add-on | Late sodium current inhibitor. No hemodynamic effects. Prolongs QTc. |
| Aspirin | 81 mg daily | Antiplatelet | Lifelong. Reduces MI and CV death. |
| Atorvastatin (Lipitor) | 40–80 mg daily | High-intensity statin | Plaque stabilization + LDL reduction. Target LDL < 70. |
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.
📋 On Rounds
Pimp Questions
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.
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)
- Start ASA 81 mg + high-intensity statin (atorvastatin 80 mg)
- Metoprolol succinate 25 mg daily (first-line anti-anginal — reduces HR and O₂ demand)
- SL nitroglycerin PRN for breakthrough episodes
- 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)
- Reassess revascularization candidacy — repeat coronary angiography
- 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
- Long-acting nitrate (isosorbide mononitrate 30-60 mg daily) if CCB alone insufficient
- AVOID beta-blockers (unopposed alpha-mediated vasoconstriction can worsen spasm)
- SL nitroglycerin PRN for acute episodes
- Avoid triggers: cocaine, triptans, ergot alkaloids, cold exposure
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
Definition
Predictable exertional chest pain, 2–10 min, relieved by rest/NTG. Fixed coronary stenosis.
Anti-Anginals
β-blocker (1st line) → CCB → long-acting nitrate → ranolazine. Layer as needed.
Risk Reduction
ASA 81mg, high-intensity statin (LDL < 70), ACEi/ARB. Lifestyle modification.
ISCHEMIA Trial
No mortality benefit of routine revascularization vs GDMT in stable CAD.
CABG Benefit
Left main, 3-vessel + ↓ EF, diabetes + multi-vessel disease.
Nitrate Tolerance
10–14h nitrate-free interval required. Dose ISMN once daily (AM).
High-YieldGI
Inflammatory Bowel Disease
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 | IV steroids → anti-TNF or vedolizumab |
| Perianal/Fistulizing | N/A | Anti-TNF (infliximab preferred) + antibiotics + surgical drainage |
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.
Extraintestinal Manifestations
- MSK: Peripheral arthritis (follows disease activity), sacroiliitis/ankylosing spondylitis (independent)
- Skin: Erythema nodosum (follows activity), pyoderma gangrenosum (independent)
- Eyes: Uveitis, episcleritis
- Hepatobiliary: Primary sclerosing cholangitis (strong UC association)
🧪 Workup
- Colonoscopy with biopsies -gold standard for diagnosis
- CT enterography/MR enterography -small bowel involvement (Crohn)
- 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. |
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. (5)
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.
- Rescue therapy: infliximab 5 mg/kg. Surgical consultation placed.
- Responded by day 5. Oral prednisone taper + infliximab maintenance initiated.
Teaching Point: Day-3 reassessment with Travis criteria is critical. Delayed rescue therapy increases colectomy and mortality risk.
📋 Case 2 — Crohn with Perianal Fistula
Patient: 26M with ileal Crohn (on azathioprine), 2 weeks of perianal pain, swelling, purulent drainage. 4-5 loose stools/day, 8 lb weight loss.
Exam: External fistula at 5 o'clock with purulent discharge. Fluctuant area = undrained abscess.
Imaging: MRI pelvis: complex perianal fistula + intersphincteric abscess (2.3 cm).
Management:
- Step 1: EUA with abscess I&D + seton placement.
- Step 2: Cipro 500 BID + metronidazole 500 TID (bridge to biologic).
- Step 3: Infliximab initiated (preferred for fistulizing Crohn). ACCENT II, 2004
- Azathioprine continued (combination reduces immunogenicity). Seton removed at 3 months.
Teaching Point: Always drain abscess BEFORE biologics. Combined medical-surgical approach is standard for fistulizing Crohn.
📋 Case 3 — Toxic Megacolon
Patient: 58F with UC on IV steroids for 4 days. Overnight: abdominal distention, absent bowel sounds, fever 39.4°C, HR 128, BP 92/58, AMS.
Labs: WBC 22K, lactate 3.8, K 2.9, Hgb 7.4.
Imaging: KUB: transverse colon 8.5 cm. No free air.
Assessment: Toxic megacolon — dilation > 6 cm + systemic toxicity.
Management:
- NPO, NG tube, aggressive IVF, correct K. IV pip-tazo. Continue IV steroids.
- Avoid: opioids, anticholinergics, loperamide, colonoscopy.
- 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.
📋 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. (5)
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.
- Rescue therapy: infliximab 5 mg/kg. Surgical consultation placed.
- Responded by day 5. Oral prednisone taper + infliximab maintenance initiated.
Teaching Point: Day-3 reassessment with Travis criteria is critical. Delayed rescue therapy increases colectomy and mortality risk.
📋 Case 2 — Crohn with Perianal Fistula
Patient: 26M with ileal Crohn (on azathioprine), 2 weeks of perianal pain, swelling, purulent drainage. 4-5 loose stools/day, 8 lb weight loss.
Exam: External fistula at 5 o'clock with purulent discharge. Fluctuant area = undrained abscess.
Imaging: MRI pelvis: complex perianal fistula + intersphincteric abscess (2.3 cm).
Management:
- Step 1: EUA with abscess I&D + seton placement.
- Step 2: Cipro 500 BID + metronidazole 500 TID (bridge to biologic).
- Step 3: Infliximab initiated (preferred for fistulizing Crohn). ACCENT II, 2004
- Azathioprine continued (combination reduces immunogenicity). Seton removed at 3 months.
Teaching Point: Always drain abscess BEFORE biologics. Combined medical-surgical approach is standard for fistulizing Crohn.
📋 Case 3 — Toxic Megacolon
Patient: 58F with UC on IV steroids for 4 days. Overnight: abdominal distention, absent bowel sounds, fever 39.4°C, HR 128, BP 92/58, AMS.
Labs: WBC 22K, lactate 3.8, K 2.9, Hgb 7.4.
Imaging: KUB: transverse colon 8.5 cm. No free air.
Assessment: Toxic megacolon — dilation > 6 cm + systemic toxicity.
Management:
- NPO, NG tube, aggressive IVF, correct K. IV pip-tazo. Continue IV steroids.
- Avoid: opioids, anticholinergics, loperamide, colonoscopy.
- 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 vs UC
Crohn: transmural, skip lesions, granulomas, fistulas. UC: mucosal, continuous from rectum, crypt abscesses.
Mild UC
Mesalamine (5-ASA) PO/PR. Mild Crohn: budesonide.
Moderate-Severe
Steroids bridge → biologics (anti-TNF, vedolizumab, ustekinumab). Thiopurines steroid-sparing.
Before Biologics
Screen TB (QFT), Hep B, vaccinations. Give live vaccines before starting.
Complications
Toxic megacolon, fistulas/abscesses (Crohn), strictures, colon cancer (surveillance at 8yr).
EIMs
Arthritis, erythema nodosum, pyoderma gangrenosum, uveitis, PSC (UC association).
EmergentGI
Small Bowel Obstruction & Ileus
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.
🔍 Overview
SBO vs Ileus
| Feature | SBO (Mechanical) | Ileus (Functional) |
|---|---|---|
| Cause | Adhesions (#1, 60–75%), hernias, tumor, volvulus | Post-operative, electrolyte imbalance, opioids, peritonitis |
| Imaging | 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.
🚨 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
🧪 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
💊 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. |
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.
📋 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.
⚡ Summary
Causes
Adhesions (#1), hernias (#2), tumor, volvulus. Ileus: post-op, opioids, electrolytes.
Imaging
CT with IV contrast = gold standard. Shows transition point, ischemia signs. XR: air-fluid levels.
Conservative Rx
NPO, NGT suction, IV fluids, electrolyte repletion. Gastrografin trial.
Surgery When
Complete SBO >48-72h, strangulation signs, closed-loop, free air, incarcerated hernia.
Strangulation Signs
Fever, peritonitis, ↑ lactate, ↑ WBC, CT: decreased enhancement, pneumatosis.
Avoid
Opioids (worsen ileus). Replace fluids aggressively (3rd-spacing significant).
EmergentGI
Cholangitis & Cholecystitis
Cholangitis: infected bile duct obstruction. Charcot triad (fever, RUQ pain, jaundice). Reynolds pentad adds AMS + shock. Emergent biliary drainage (ERCP). Cholecystitis: gallbladder inflammation -Murphy sign, cholecystectomy within 72h.
🔍 Overview
Cholangitis vs Cholecystitis
| Feature | Acute Cholangitis | Acute Cholecystitis |
|---|---|---|
| Pathophys | Bile duct obstruction + infection → bacteremia | Gallbladder outlet obstruction (stone in cystic duct) → inflammation ± infection |
| Classic signs | Charcot triad: fever + RUQ pain + jaundice | 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 | Antibiotics + elective/semi-urgent biliary drainage |
| Grade II | Moderate | 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 Severity Grading — Acute Cholecystitis
| Grade | Severity | Criteria | Management |
|---|---|---|---|
| Grade I | Mild | Healthy patient, no organ dysfunction, mild GB inflammation | Early laparoscopic cholecystectomy |
| Grade II | Moderate | Any of: WBC >18k, palpable RUQ mass, duration >72h, gangrenous/emphysematous GB, pericholecystic abscess | Early chole by experienced surgeon or percutaneous drainage if high risk |
| Grade III | Severe | Organ dysfunction (cardiovascular, neurologic, respiratory, renal, hepatic, hematologic) | Percutaneous cholecystostomy (bridge) → interval cholecystectomy |
ERCP vs MRCP
| Feature | MRCP | ERCP |
|---|---|---|
| Purpose | Diagnostic — non-invasive biliary imaging | 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 |
| 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.
- 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
- 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 |
| 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 | Tailor to cultures |
🧪 Workup
- RUQ ultrasound -first-line. GB stones, wall thickening, pericholecystic fluid, CBD dilation
- MRCP -if US inconclusive for CBD stones
- HIDA scan -if cholecystitis diagnosis unclear (non-filling of GB = cystic duct obstruction)
- CBC, CMP (bilirubin, ALP, GGT, AST, ALT), lipase
- 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 cholangitis and complicated cholecystitis |
| 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 |
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.
📋 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
Cholangitis
Infected bile duct obstruction. Charcot triad: fever + RUQ pain + jaundice. ERCP for drainage.
Reynolds Pentad
Charcot triad + AMS + shock = toxic cholangitis. EMERGENT ERCP. 50% mortality without drainage.
Cholecystitis
GB wall inflammation. Murphy sign. US first-line. Lap chole within 72h.
Antibiotics
Zosyn (first-line), cipro + flagyl (PCN allergy), meropenem (severe).
Imaging
RUQ US first. MRCP for CBD stones. HIDA if US inconclusive (sens 97%).
Organisms
E. coli, Klebsiella, Enterococcus, Bacteroides. Polymicrobial. Cover GN + anaerobes.
URGENTGI
Acute Alcoholic Hepatitis
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
- DF < 32: mild-moderate → supportive care
- DF ≥ 32: severe → consider prednisolone
MELD Score
- MELD also predicts mortality in alcoholic hepatitis
- MELD > 21: significant mortality risk, correlates with DF ≥ 32
🚨 Management
DF < 32 -Mild-Moderate
- Supportive care -these patients are MALNOURISHED
- 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) |
| CBC | Leukocytosis common; macrocytic anemia (MCV > 100) |
| BMP | Creatinine (HRS surveillance), electrolytes |
| Hepatitis serologies | Rule out viral hepatitis (HBV, HCV) |
| Lipase | Rule out concurrent pancreatitis |
| RUQ ultrasound + Doppler | Evaluate liver, rule out biliary obstruction, assess portal flow |
| Maddrey DF | Calculate: 4.6 × (PT − control PT) + bilirubin |
| MELD score | Additional prognostic tool |
RoundsRx Licensed Content - Unauthorized Use Prohibited💊 Medications
| Drug | Dose | Indication |
|---|---|---|
| Prednisolone (Orapred) | 40 mg PO daily × 28 days → taper | Severe AH (DF ≥ 32). Stop if Lille > 0.45 at day 7. |
| Thiamine (Vitamin B1) | 100 mg IV/PO daily | All patients -prevent Wernicke encephalopathy |
| Folic acid | 1 mg PO daily | All patients -folate deficiency common in alcoholics |
| Multivitamin | 1 tab PO daily | Nutritional repletion |
| Nutritional supplementation | 35–40 kcal/kg/day | High-calorie, high-protein diet. Consult dietitian. |
| Lactulose | 15–30 mL PO q2–4h titrate to 3–4 BM/day | If hepatic encephalopathy present |
📋 On Rounds
Pimp Questions
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.
📣 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
Diagnosis
AST:ALT > 2:1, AST 2–6× ULN, jaundice, heavy alcohol use. Calculate Maddrey DF.
Maddrey DF
4.6 × (PT − control PT) + bilirubin. DF ≥ 32 = severe → consider prednisolone.
Treatment
Prednisolone 40 mg × 28d if DF ≥ 32. Lille at day 7. Nutrition is paramount.
Lille Score
> 0.45 at day 7 = non-responder → STOP steroids. < 0.45 → complete course.
STOPAH 2015
Pentoxifylline: NO benefit. Prednisolone: modest 28-day benefit, no long-term benefit.
Nutrition
35–40 kcal/kg/day + thiamine + folate + MVI. These patients are malnourished.
EMERGENTGI/Nephro
Hepatorenal Syndrome
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)
- → Effective arterial underfilling → activation of RAAS, sympathetic nervous system, ADH
- → Renal vasoconstriction → decreased GFR
- → 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, 2024. First drug specifically approved for HRS.
Step 5 -TIPS
Transjugular intrahepatic portosystemic shunt -reduces portal pressure. Consider if appropriate candidate.
Definitive -Liver transplant
Liver transplant is the only cure. HRS often resolves after successful transplant because the underlying portal hypertension is corrected.
🧪 Workup
| Test | Expected in HRS | Purpose |
|---|---|---|
| BMP | ↑ Cr, ↑ BUN | Baseline and trending renal function |
| UA with microscopy | Bland (no casts, no cells) | ATN has muddy brown casts; GN has RBC casts |
| Urine Na | < 10 mEq/L | Very low urine Na = avid renal sodium retention |
| FENa | < 1% | Pre-renal physiology (kidneys structurally normal) |
| Renal ultrasound | Normal kidneys | Rule out obstruction |
| Hepatic panel, INR, albumin | Deranged (cirrhosis) | Confirm underlying liver disease severity |
| Diagnostic paracentesis | Rule out SBP | SBP is a common trigger for HRS |
💊 Medications
| Drug | Dose | Mechanism / Notes |
|---|---|---|
| Midodrine (ProAmatine) | 7.5–12.5 mg PO TID | Alpha-1 agonist → splanchnic vasoconstriction |
| Octreotide (Sandostatin) | 100–200 mcg SQ TID | Inhibits splanchnic vasodilation |
| Albumin 25% | 25–50 g IV daily | Volume expansion + oncotic pressure support |
| Terlipressin (Terlivaz) | 0.5–1 mg IV q6h | 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
- Monitor closely for respiratory adverse events (pulmonary edema) — key safety concern
- Daily Cr, urine output, volume status assessment
- 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
Definition
AKI in cirrhosis. Diagnosis of exclusion. Bland UA, FENa < 1%, urine Na < 10.
Pathophys
Splanchnic vasodilation → underfilling → renal vasoconstriction. Kidneys structurally normal.
Step 1–2
Stop nephrotoxins/diuretics/BBs. Albumin 1g/kg × 2 days challenge.
Triple Therapy
Midodrine + octreotide + albumin. Classic regimen for HRS.
Terlipressin
FDA-approved 2022 (CONFIRM trial). Preferred if available. Watch for respiratory events.
Definitive
Liver transplant is the only cure. TIPS as bridge in select patients.
URGENTNephrology
Hypernatremia
Na⁺ > 145 mEq/L -almost ALWAYS from free water deficit, not sodium excess. Causes: inadequate water intake (altered mental status, intubated, elderly), diabetes insipidus, osmotic diuresis, GI losses. Correct ≤10 mEq/L per 24 hours for chronic hypernatremia.
🔍 Overview
Definition
- Na > 145 mEq/L -almost always from free water deficit (not sodium excess)
- Serum osmolality is always elevated (> 295 mOsm/kg)
Causes
| Category | Examples |
|---|---|
| Inadequate water intake | Altered mental status, intubated patients without free water, elderly with impaired thirst, NPO without adequate IVF |
| Diabetes insipidus | Central DI: post-neurosurgery, pituitary injury, brain death. Nephrogenic DI: lithium, hypercalcemia, hypokalemia |
| Osmotic diuresis | Hyperglycemia (DKA/HHS), mannitol, urea (high-protein TPN) |
| GI losses | Diarrhea (especially osmotic diarrhea -lactulose), vomiting, NG suction |
| Renal losses | Loop diuretics, post-obstructive diuresis |
🚨 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
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.
🧪 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.
📣 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 |
⚡ Summary
Definition
Na > 145. Almost always free water deficit. Serum osm always elevated.
Causes
Inadequate intake (most common), DI (central/nephrogenic), osmotic diuresis, GI losses.
Free Water Deficit
FWD = TBW × (Na/140 − 1). TBW = weight × 0.5 (F) or 0.6 (M).
Treatment
D5W or 0.45% NS or free water PO/NG. DDAVP for central DI.
Correction Rate
≤10 mEq/24h chronic. Faster OK if acute (< 48h). Overcorrection → cerebral edema.
DI Workup
Urine osm < 300 → give DDAVP. Concentrates = central DI. No response = nephrogenic DI.
URGENTGI/Surgery
Gallstone Pancreatitis
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.
🧪 Workup
| Test | Purpose / Key Values |
|---|---|
| Lipase | > 3× ULN diagnostic. Don't need to normalize before feeding/surgery. |
| ALT | > 150 U/L = ~85% PPV for gallstone etiology -very helpful! |
| Total/direct bilirubin | Elevated = stone may still be impacted. Improving = stone likely passed. |
| Alk phos | Elevated in biliary obstruction |
| CBC | Leukocytosis (inflammation), hemoconcentration (dehydration) |
| BMP | Cr (organ failure), glucose, calcium |
| CRP at 48h | 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.
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
Etiology
Gallstones ~40% of pancreatitis. ALT > 150 = ~85% PPV for gallstones.
Initial Rx
Goal-directed LR (not aggressive per WATERFALL). Pain control. Early feeding. No prophylactic abx.
Cholecystectomy
Same admission for mild (PONCHO). Delay 4-6 wk for severe. 25-30% recurrence if discharged without.
ERCP
Only for cholangitis or persistent obstruction. NOT routine (APEC 2024).
Key Trials
PONCHO 2015 (same-admission chole), WATERFALL 2022 (no aggressive fluids), APEC 2024 (no routine ERCP).
Monitoring
LFTs daily (improving bili = stone passed). CRP 48h. CT only if not improving day 3-5.
High-YieldNephro
Metabolic Alkalosis
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).
Classification by Urine Chloride
| UCl < 20 (Saline-Responsive) | UCl > 20 (Saline-Resistant) |
|---|---|
| Vomiting / NGT suction (#1 cause) | Primary hyperaldosteronism |
| Post-diuretic (remote use) | Cushing syndrome |
| Post-hypercapnic | Current diuretic use |
| Chloride-losing diarrhea (rare) | Bartter/Gitelman syndrome |
| Treatment: NS + KCl | Treatment: Treat underlying cause |
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 (remote use), post-hypercapnic | Hyperaldosteronism, Cushing, Bartter/Gitelman, licorice ingestion, current 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 syndrome mimics chronic loop diuretic use (Na⁺/K⁺/Cl⁻ wasting, metabolic alkalosis, hypokalemia). Gitelman syndrome mimics chronic thiazide use (similar but with hypocalciuria and hypomagnesemia). Both are autosomal recessive channelopathies.
🚨 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.
Treatment Algorithm
| Step | Condition | Action |
|---|---|---|
| 1 | Check urine Cl⁻ | UCl < 20 → saline-responsive. UCl > 20 → saline-resistant. |
| 2a | Saline-responsive | IV NS 125–250 mL/h + KCl 10–40 mEq/h. Goal: replace Cl⁻ deficit and correct volume. |
| 2b | Saline-resistant | Identify and treat underlying cause: spironolactone for hyperaldosteronism, stop offending diuretics, dexamethasone suppression for Cushing. |
| 3 | Refractory (HCO₃⁻ > 40 despite above) | Acetazolamide 250–500 mg IV q6–12h — forces renal HCO₃⁻ wasting. Monitor K⁺ (causes K⁺ loss). |
| 4 | Severe / life-threatening (pH > 7.55) | 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.
🧪 Workup
- ABG -confirm primary metabolic alkalosis (↑ pH, ↑ HCO₃⁻, compensatory ↑ PaCO₂)
- Urine chloride -key classification tool. < 20 = saline-responsive, > 20 = saline-resistant
- BMP -K⁺ (usually low), Cl⁻ (usually low)
- Urine electrolytes -Na⁺, K⁺, Cl⁻
- If saline-resistant: renin, aldosterone, cortisol
💊 Medications
| Drug | Dose | Indication |
|---|---|---|
| IV Normal Saline | 125–250 mL/h | Saline-responsive alkalosis -provides Cl⁻ |
| Potassium Chloride (KCl) | 10–40 mEq/h IV (max 40 mEq/h via central) | K⁺ repletion -essential for correction |
| Acetazolamide (Diamox) | 250–500 mg IV q6–12h | Refractory alkalosis -carbonic anhydrase inhibitor → renal HCO₃⁻ wasting |
| Spironolactone (Aldactone) | 25–100 mg PO daily | Hyperaldosteronism-related alkalosis |
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.
Assessment:
- Primary metabolic alkalosis (pH 7.56, HCO₃⁻ 38)
- Expected PaCO₂ = 0.7 × 38 + 21 = 47.6 — matches (appropriate respiratory compensation)
- Urine Cl⁻: 8 mEq/L → saline-responsive
- Severe hypokalemia (2.6) and hypochloremia (78)
Treatment:
- 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.
📋 Case 2 — Diuretic-Induced Alkalosis
Patient: 68M with CHF (EF 25%) on furosemide 80 mg BID. Admitted for dyspnea. Labs: pH 7.52, PaCO₂ 50, HCO₃⁻ 36, K⁺ 2.9, Cl⁻ 82, Cr 1.4. Urine Cl⁻: 42 mEq/L.
Assessment:
- Metabolic alkalosis from chronic loop diuretic use (contraction alkalosis + Cl⁻/K⁺ wasting)
- UCl is 42 — but patient is on active furosemide → UCl is unreliable. This is saline-responsive masquerading as saline-resistant.
- Challenge: cannot give aggressive NS to a patient with EF 25% — will worsen volume overload
Treatment:
- Hold or reduce furosemide — stop the ongoing Cl⁻/K⁺ losses
- Acetazolamide 250 mg IV q12h — forces renal HCO₃⁻ wasting without volume loading (ideal for CHF patients who cannot tolerate NS)
- KCl 40 mEq PO q8h + IV KCl as needed — K⁺ repletion essential
- Spironolactone 25 mg daily — K⁺-sparing diuretic, also blocks aldosterone-driven H⁺ secretion
- Monitor: Daily weights, I/Os, BMP q8h, telemetry (K⁺ 2.9 = arrhythmia risk)
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
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
- Urine Cl⁻: 38 mEq/L → saline-resistant
- Resistant HTN + spontaneous hypokalemia + metabolic alkalosis = screen for primary hyperaldosteronism
Workup:
- 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.
📋 On Rounds
Pimp Questions
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.
Assessment:
- Primary metabolic alkalosis (pH 7.56, HCO₃⁻ 38)
- Expected PaCO₂ = 0.7 × 38 + 21 = 47.6 — matches (appropriate respiratory compensation)
- Urine Cl⁻: 8 mEq/L → saline-responsive
- Severe hypokalemia (2.6) and hypochloremia (78)
Treatment:
- 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.
📋 Case 2 — Diuretic-Induced Alkalosis
Patient: 68M with CHF (EF 25%) on furosemide 80 mg BID. Admitted for dyspnea. Labs: pH 7.52, PaCO₂ 50, HCO₃⁻ 36, K⁺ 2.9, Cl⁻ 82, Cr 1.4. Urine Cl⁻: 42 mEq/L.
Assessment:
- Metabolic alkalosis from chronic loop diuretic use (contraction alkalosis + Cl⁻/K⁺ wasting)
- UCl is 42 — but patient is on active furosemide → UCl is unreliable. This is saline-responsive masquerading as saline-resistant.
- Challenge: cannot give aggressive NS to a patient with EF 25% — will worsen volume overload
Treatment:
- Hold or reduce furosemide — stop the ongoing Cl⁻/K⁺ losses
- Acetazolamide 250 mg IV q12h — forces renal HCO₃⁻ wasting without volume loading (ideal for CHF patients who cannot tolerate NS)
- KCl 40 mEq PO q8h + IV KCl as needed — K⁺ repletion essential
- Spironolactone 25 mg daily — K⁺-sparing diuretic, also blocks aldosterone-driven H⁺ secretion
- Monitor: Daily weights, I/Os, BMP q8h, telemetry (K⁺ 2.9 = arrhythmia risk)
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
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
- Urine Cl⁻: 38 mEq/L → saline-resistant
- Resistant HTN + spontaneous hypokalemia + metabolic alkalosis = screen for primary hyperaldosteronism
Workup:
- 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
Classification
UCl < 20 = saline-responsive (vomiting, diuretics). UCl > 20 = saline-resistant (hyperaldo, Cushing).
Saline-Responsive Rx
IV NS + KCl. Provides Cl⁻ for kidney to excrete HCO₃⁻. Fix volume + chloride deficit.
Saline-Resistant Rx
Treat cause: spironolactone for hyperaldo, stop offending diuretics.
Refractory
Acetazolamide (Diamox) -forces renal HCO₃⁻ wasting. Severe: HCl infusion or dialysis.
Hypokalemia
Perpetuates alkalosis via paradoxical aciduria. MUST replace K⁺ to correct alkalosis.
Key Lab
Urine chloride (NOT sodium) -more reliable in alkalosis because of obligatory bicarbonuria.
EmergentNeurology
Intracerebral Hemorrhage
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.
🔍 Overview
Etiology by Location
| Location | Most Likely Cause |
|---|---|
| Basal ganglia / putamen | Hypertension (#1 cause, #1 location) |
| Thalamus | Hypertension |
| Pons | Hypertension |
| Cerebellum | Hypertension (surgical emergency if > 3 cm) |
| Lobar (cortical) | Cerebral amyloid angiopathy (elderly), AVM (young), tumor |
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). |
| Dabigatran (Pradaxa) | Idarucizumab (Praxbind) | 5 g IV (two 2.5g vials) | Monoclonal antibody fragment. Immediate, complete reversal. RE-VERSE AD, 2017 |
| Rivaroxaban / Apixaban (Xa inhibitors) | Andexanet alfa (Andexxa) | 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
- Avoid: hyperthermia (active cooling to normothermia), hyperglycemia (target glucose 140–180), hyponatremia
- 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%) |
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
- Neuro checks q1h, repeat CT at 6 hours
- ICH Score = 1 (GCS 12 = +1) → 13% predicted 30-day mortality
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
- Nicardipine drip → target SBP < 140
- ICH Score = 4 (GCS 10 = +1, volume ≥ 30 = +1, IVH = +1, age ≥ 80 = +1) → 97% predicted mortality
- Repeat INR 30 min after PCC — goal < 1.5
- 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.
📋 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
- Neuro checks q1h, repeat CT at 6 hours
- ICH Score = 1 (GCS 12 = +1) → 13% predicted 30-day mortality
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
- Nicardipine drip → target SBP < 140
- ICH Score = 4 (GCS 10 = +1, volume ≥ 30 = +1, IVH = +1, age ≥ 80 = +1) → 97% predicted mortality
- Repeat INR 30 min after PCC — goal < 1.5
- 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
Diagnosis
Non-contrast CT head STAT. Hyperdense acute blood. CTA for spot sign (active bleeding).
BP Target
SBP < 140 within 1h (INTERACT2). Nicardipine or clevidipine drip. A-line for monitoring.
Anticoag Reversal
Warfarin → 4F-PCC + Vit K. Dabigatran → idarucizumab. Xa-inhibitors → andexanet or PCC.
Surgery
Cerebellar ICH > 3cm or with hydrocephalus → surgical evacuation. Neurosurgery consult for all.
ICP Management
HOB 30°, mannitol/HTS, EVD if hydrocephalus. Target ICP < 20, CPP > 60.
Prognosis
ICH Score predicts 30-day mortality. Do NOT use as sole basis for withdrawal of care.
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.
🚨 Management
Acute Migraine Treatment
| Severity | Treatment |
|---|---|
| Mild-moderate | NSAIDs (Ibuprofen (Advil) 400–800mg, Naproxen (Aleve) 500mg) + Metoclopramide (Reglan) 10mg or antiemetic |
| Moderate-severe | Sumatriptan (Imitrex) 6mg SC or 50–100mg PO. Contraindicated in CAD, uncontrolled HTN, prior stroke. |
| ER/refractory | "Migraine cocktail": Ketorolac (Toradol) 30mg IV + Prochlorperazine (Compazine) 10mg IV + Diphenhydramine (Benadryl) 25mg IV + IV fluids |
| Status migrainosus | Dexamethasone (Decadron) 10mg IV + above cocktail. Dihydroergotamine (DHE) protocol if refractory. |
Migraine Prophylaxis (≥ 4 headache days/month)
- Topiramate (Topamax) 25–100mg BID -weight loss side effect
- Propranolol (Inderal) 40–160mg daily -also treats anxiety, tremor
- Amitriptyline (Elavil) 10–75mg QHS -good for comorbid insomnia/tension-type
- Valproate (Depakote) 500–1500mg daily -teratogenic, weight gain
- CGRP monoclonal antibodies: Erenumab (Aimovig), Fremanezumab (Ajovy), Galcanezumab (Emgality)
🧪 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. |
| Topiramate (Topamax) | 25–100mg BID | Prophylaxis | Weight loss, paresthesias, kidney stones, word-finding difficulty. |
| Erenumab (Aimovig) | 70–140mg SC monthly | Prophylaxis | CGRP antibody. Few side effects. Constipation. |
What is the workup for thunderclap headache?
Thunderclap = maximal intensity within seconds to 1 minute. #1 concern: subarachnoid hemorrhage (SAH). Workup: (1) Non-contrast CT head -sensitivity 98% 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)
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.
📋 On Rounds
Pimp Questions
What is the workup for thunderclap headache?
Thunderclap = maximal intensity within seconds to 1 minute. #1 concern: subarachnoid hemorrhage (SAH). Workup: (1) Non-contrast CT head -sensitivity 98% 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)
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.
⚡ Summary
Red Flags
SNOOP: Systemic, Neuro deficits, Onset sudden, Older >50, Positional/Progressive.
Migraine Rx
Mild: NSAIDs. Moderate: triptans (sumatriptan). Severe: IV cocktail (ketorolac + compazine + benadryl).
Prophylaxis
≥ 4 headache days/month. Topiramate, propranolol, amitriptyline, or CGRP antibodies.
Thunderclap
CT head → LP (xanthochromia) → CTA/MRA. SAH until proven otherwise.
Cluster Headache
High-flow O₂ (12-15L NRB) + sumatriptan SC. Prophylaxis: verapamil.
MOH
Triptans > 10d/mo, NSAIDs > 15d/mo. Withdraw offending agent + start preventive.
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.
- Pain management -often severe. Opioids appropriate.
Surgery vs Radiation
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
- Neuro exam -motor level, sensory level, rectal tone (cauda equina), reflexes
- 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 |
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.
📋 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.
Management:
- Emergent neurosurgery consult for decompressive laminectomy + abscess drainage (neurologic deficit = operative emergency)
- 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
Presentation
Back pain (95%) → radiculopathy → weakness → sensory level → bowel/bladder (late, poor prognosis).
Immediate Action
Dexamethasone 10mg IV STAT. MRI entire spine with contrast. Neurosurgery + rad onc consult.
Key Predictor
Ambulatory status at diagnosis. 80% who walk at diagnosis remain ambulatory. 10% regain if paraplegic.
Imaging
MRI entire spine with gadolinium. 30% have multiple levels. CT myelogram if MRI contraindicated.
Causes
Metastatic (#1): lung, breast, prostate, RCC, myeloma. Also: abscess, hematoma, disc herniation.
Treatment
Surgery + radiation (Patchell trial) > radiation alone for single-level disease with good prognosis.
EmergentEM
Trauma Primary & Secondary Survey
ATLS framework: ABCDE primary survey identifies life threats in minutes. Adjuncts: FAST, CXR, pelvic XR. Secondary survey is head-to-toe after stabilization. Hemorrhagic shock classification guides resuscitation.
🔍 Overview
Primary Survey (ABCDE)
| Step | Assessment | Interventions |
|---|---|---|
| A -Airway | Patent? Speaking? Stridor? Facial/neck trauma? | Jaw thrust (maintain C-spine), suction, definitive airway if needed |
| B -Breathing | RR, SpO₂, breath sounds bilateral? Tracheal deviation? Chest wall movement? | Needle decompression (tension pneumo), chest tube, seal open pneumo |
| C -Circulation | HR, BP, skin (cool/clammy?), active bleeding? Pelvis stable? | 2 large-bore IVs, tourniquets, pelvic binder, MTP if needed |
| D -Disability | GCS, pupils, gross motor/sensory | Treat ↑ ICP (HOB 30°, mannitol/HTS), identify herniation |
| E -Exposure | Fully undress, log roll, inspect everywhere | Warm blankets, prevent hypothermia |
Hemorrhagic Shock Classification
| Class | Blood Loss | HR | BP | Mental Status |
|---|---|---|---|---|
| I | < 750 mL (15%) | Normal | Normal | Normal |
| II | 750–1500 mL (15–30%) | ↑ (100–120) | Normal | Anxious |
| III | 1500–2000 mL (30–40%) | ↑ (>120) | ↓ | Confused |
| IV | > 2000 mL (>40%) | ↑ (>140) | ↓↓ | Obtunded |
RoundsRx Licensed Content - Unauthorized Use Prohibited🚨 Management
Adjuncts to Primary Survey
- FAST exam -Focused Assessment with Sonography in Trauma. 4 views: RUQ, LUQ, subxiphoid, suprapubic. Identifies free fluid.
- CXR (AP supine) -pneumothorax, hemothorax, mediastinal widening
- Pelvic XR -pelvic fracture (hemodynamic instability source)
- 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.
🧪 Workup
- FAST exam -bedside, during primary survey
- CXR, pelvic XR
- CT pan-scan (head, C-spine, chest, abdomen/pelvis with IV contrast) -stable patients
- CBC, BMP, coags, type & crossmatch, lactate, ABG
- Urine drug screen, blood alcohol, pregnancy test
- Tetanus status
💊 Medications
| Drug | Dose | Purpose |
|---|---|---|
| Tranexamic Acid (TXA) | 1g IV over 10 min → 1g over 8h | Antifibrinolytic -within 3h of injury |
| pRBC / FFP / Platelets | 1:1:1 ratio | MTP for hemorrhagic shock Class III–IV |
| Ketamine (Ketalar) | 1–2 mg/kg IV | RSI induction -hemodynamically stable, bronchodilator |
| Rocuronium (Zemuron) | 1.2 mg/kg IV | Paralytic for RSI -longer duration but sugammadex reversible |
| Norepinephrine (Levophed) | 0.1–0.5 mcg/kg/min | Vasopressor -AFTER volume resuscitation, not as substitute |
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).
📋 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).
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.
Management:
- Activate massive transfusion protocol — 1:1:1 (pRBC:FFP:platelets) PROPPR, 2015
- 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.
Key findings: Cushing triad (HTN + bradycardia + irregular breathing) = elevated ICP. Ipsilateral fixed dilated pupil + contralateral hemiplegia = uncal herniation. Epidural = "talk and die" lesion if not evacuated.
Management:
- 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
Primary Survey
ABCDE: Airway (c-spine), Breathing, Circulation, Disability (GCS), Exposure. Fix life threats as found.
FAST
4 views: RUQ, LUQ, subxiphoid, suprapubic. Detects free fluid ≥ 200mL. Cannot detect retroperitoneal bleed.
Shock Classes
I: <15%, normal. II: 15-30%, tachy. III: 30-40%, ↓BP, confused. IV: >40%, obtunded.
MTP
1:1:1 pRBC:FFP:Platelets. TXA within 3h. Calcium replacement. Permissive hypotension.
Secondary Survey
Head-to-toe after stabilization. Log roll. Complete neuro exam. "Tubes and fingers in every orifice."
Foley Contraindications
Blood at meatus, high-riding prostate, scrotal hematoma → RUG first before Foley.
EmergentEM
Acute Abdomen
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.
🔍 Overview
Differential by Location
| Location | Key Diagnoses |
|---|---|
| RUQ | Cholecystitis, hepatitis, hepatic abscess, Fitz-Hugh-Curtis, RLL pneumonia |
| Epigastric | Peptic ulcer, pancreatitis, MI (inferior), aortic dissection/aneurysm |
| LUQ | Splenic infarct/rupture, pancreatitis (tail), LLL pneumonia |
| RLQ | Appendicitis, Meckel's, ovarian torsion, ectopic pregnancy, IBD |
| Suprapubic | UTI, urinary retention, ovarian torsion, ectopic pregnancy, cystitis |
| LLQ | Diverticulitis, ovarian pathology, sigmoid volvulus, IBD |
| Periumbilical | Early appendicitis, SBO, mesenteric ischemia, AAA rupture |
| Diffuse | Perforated viscus, peritonitis, mesenteric ischemia, DKA, SBO |
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.
🚨 Management
Immediate Steps
- ABCs -stabilize hemodynamics first
- IV access, fluids, labs -CBC, BMP, lipase, LFTs, lactate, UA, β-hCG (all women)
- 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
🧪 Workup
- CT abdomen/pelvis with IV contrast -workhorse imaging for acute abdomen
- 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
💊 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 |
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.
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. 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. 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.
📋 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.
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. 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. 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
RLQ Pain
Appendicitis (#1). Also: Meckel's, ovarian torsion, ectopic, IBD. CT to confirm.
Cannot Miss
AAA rupture, mesenteric ischemia, ectopic pregnancy, torsion, perforated viscus.
β-hCG
ALL women of childbearing age. No exceptions. Ectopic is #1 cause of 1st-trimester death.
Pain Management
Opioids DO NOT mask surgical findings. Treat pain. Ketorolac for colic.
Free Air
Upright CXR or CT. Free air under diaphragm = perforated viscus → emergent surgery.
Mesenteric Ischemia
Pain out of proportion to exam. ↑ Lactate. CTA STAT. Afib is major risk factor.
RoundsRx Licensed Content - Unauthorized Use Prohibited
EmergentHeme/Onc
Superior Vena Cava Syndrome
Obstruction of SVC → facial/upper extremity swelling, JVD, dyspnea. Malignancy causes 60-85% (lung cancer #1, lymphoma #2). Thrombosis 20-40% (central venous catheters, pacemaker leads). CT with IV contrast is diagnostic. Endovascular stenting provides fastest relief. True emergency only if airway compromise or cerebral edema.
🔍 Overview
Etiology
| Cause | Frequency | Details |
|---|---|---|
| Lung cancer | ~50% | NSCLC > SCLC. Right-sided tumors compress SVC directly. #1 malignant cause. |
| Lymphoma | ~15% | Mediastinal mass — NHL > Hodgkin. Often highly chemo-sensitive. |
| Other malignancy | ~10% | Thymoma, germ cell tumors, metastatic disease (breast, renal). |
| Thrombosis (catheter-related) | 20–40% | Central venous catheters, ports, pacemaker/defibrillator leads, dialysis catheters. Rising incidence with increasing device use. |
| Other benign | <5% | Fibrosing mediastinitis (histoplasmosis), aortic aneurysm, goiter, sarcoidosis. |
Pathophysiology
- SVC obstruction (extrinsic compression, intraluminal thrombus, or direct invasion) → venous hypertension in head, neck, upper extremities
- Collateral formation — azygos, internal mammary, lateral thoracic, paraspinous veins dilate over days to weeks to decompress
- Gradual onset allows collateral development → most patients are hemodynamically stable
- Rapid-onset obstruction (e.g., acute thrombosis) → insufficient collaterals → more severe symptoms, higher risk of cerebral edema
Clinical Presentation
- Facial and neck swelling — periorbital edema, facial plethora (worse in the morning, worse when bending forward or supine)
- Upper extremity edema — bilateral, non-pitting
- Dyspnea — most common symptom (~60%), from laryngeal/bronchial edema or pleural effusion
- Cough, hoarseness — vocal cord or recurrent laryngeal nerve edema
- Head fullness, headache — worse when bending forward (Pemberton sign)
- JVD, prominent chest wall veins — visible collateral circulation across anterior chest
- 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) | Urgent |
| Grade 4 | Life-threatening | Stridor, laryngeal edema, cerebral edema (AMS, seizures), hemodynamic collapse | Emergency |
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. |
| Venous duplex US | Adjunct | Upper extremity venous duplex if catheter-related thrombosis suspected. Cannot visualize intrathoracic SVC directly. |
Laboratory Studies
- 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)
🚨 Management
Emergent Management (Grade 4 — Airway/Cerebral Edema)
- 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. |
| DLBCL (NHL) | R-CHOP | Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisone | >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.
- CT-guided biopsy → NSCLC (squamous cell). PD-L1 testing and molecular profiling sent.
- 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.
- Tumor lysis syndrome prophylaxis — aggressive IVF, rasburicase for uric acid 9.2.
- 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.
Daily Rounds Checklist
- Airway assessment → stridor, voice changes, dyspnea severity? Grade today vs yesterday?
- Edema trajectory → facial/arm edema improving or worsening? Measure arm circumference daily.
- SpO₂ trend → O₂ requirement stable or increasing?
- Tissue diagnosis → biopsy done? Pathology back? Flow cytometry results? Molecular markers pending?
- Stent status → if stented, any complications (migration, re-occlusion)? Dual antiplatelet therapy started?
- Anticoagulation → if thrombotic: aPTT in range? Transitioning to oral? Duration plan?
- Access → ALL IVs, blood draws, and BP cuffs on lower extremities? No upper extremity access on affected side?
- TLS screen → if bulky malignancy: uric acid, potassium, phosphorus, calcium, LDH trending?
- Definitive treatment plan → oncology consulted? Chemo/radiation start date? IR follow-up if stented?
- HOB elevated → maintained at 30-45 degrees?
Monitoring
| Parameter | Frequency | Target / Action |
|---|---|---|
| Airway assessment (stridor, voice) | q4h initially | Any new stridor = emergent reassessment + ICU |
| SpO₂ | Continuous | > 92%; escalate O₂ delivery if dropping |
| Facial/arm edema | q8-12h | Measure arm circumference. Document subjective improvement. |
| aPTT (if on heparin) | q6h until stable | Target 60-80 seconds (1.5-2.5x control) |
| CBC | Daily | Monitor for thrombocytopenia (HIT screen if platelets drop > 50%) |
| BMP | Daily | Renal function, electrolytes (especially if TLS risk) |
| LDH, uric acid | q12-24h if TLS risk | Rising uric acid → rasburicase; rising K⁺/PO₄ = TLS |
| Repeat CT chest | After treatment initiation | Assess response: tumor shrinkage, stent patency, collateral resolution |
⚡ Summary
Etiology
Malignancy 60-85% (lung cancer #1, lymphoma #2). Thrombosis 20-40% (catheters, pacemakers). Benign causes rare (<5%).
Presentation
Facial/arm edema, JVD, dyspnea, prominent chest wall collaterals. Worse supine/bending forward. Pemberton sign positive.
Diagnosis
CT chest with IV contrast (test of choice). Get tissue biopsy BEFORE treatment in stable patients. Bypass biopsy only for Grade 4.
Emergent (Grade 4)
Airway/cerebral edema. Dexamethasone 4 mg IV q6h + emergent SVC stenting. Do NOT delay for biopsy.
Malignant Rx
SCLC/lymphoma → chemo (most responsive). NSCLC → radiation ± chemo. Stenting for rapid symptom relief (>90% success).
Thrombotic Rx
Anticoagulation (heparin → DOAC). Remove catheter if possible. Catheter-directed thrombolysis if acute/severe.
Avoid
Upper extremity IVs, BP, blood draws on affected side. Use femoral/lower extremity access only.
Key Pearl
Most SVC syndrome is NOT a true emergency. Collaterals form over days-weeks. Only Grade 4 (stridor, cerebral edema) requires emergent treatment.
📄 One Pager
Heme/Onc · One Pager
SVC Syndrome
Tissue diagnosis first (unless Grade 4). Stenting = fastest relief. SCLC and lymphoma are most chemo-responsive. Avoid upper extremity access.
🔬 Etiology
- Lung cancer — #1 cause (~50%), right-sided tumors
- Lymphoma — #2 (~15%), NHL > Hodgkin
- Thrombosis — 20-40%, catheters/pacemakers/ports
- Other — thymoma, germ cell, fibrosing mediastinitis
🩺 Clinical Features
- Facial/neck/arm edema (worse bending forward)
- Dyspnea, cough, head fullness
- JVD, chest wall collateral veins
- Pemberton sign (arms raised → facial congestion)
- Grades 0-4 (only Grade 4 = true emergency)
⏱️ Emergency (Grade 4) Algorithm
1
Elevate HOB to 45°. Supplemental O₂. Prepare for difficult airway.
2
Dexamethasone 4 mg IV q6h — reduce airway/cerebral edema immediately.
3
Emergent SVC stenting — fastest relief (>90% success). Call IR stat.
4
Tissue diagnosis AFTER stabilization — biopsy once airway is secured.
💉 Malignant Rx
SCLCCisplatin/Etoposide (77%)
LymphomaR-CHOP (>80%)
NSCLCRadiation ± chemo (60%)
Germ cellBEP (highly sensitive)
SVC stentBridge or refractory
🩸 Thrombotic Rx
Heparin (UFH)80 u/kg → 18 u/kg/hr
Enoxaparin1 mg/kg SC q12h
Apixaban10 BID x7d → 5 BID
Catheter-directed tPA0.5-1 mg/hr x 12-24h
Remove catheterIf no longer needed
⚠️ Pitfalls
- Treating before tissue diagnosis
- Upper extremity IVs or BP on affected side
- Calling all SVC syndrome an "emergency"
- Steroids before biopsy (obscures lymphoma)
- Missing TLS in bulky malignancy
- Forgetting to screen for germ cell (AFP, hCG)
Rounds · Hematology / Oncology
NCCN 2025 · UpToDate · DeVita 2023
EssentialPalliative
Code Status & Advance Directives
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) |
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. |
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 |
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 the conversation on "what would the patient want?" (substituted judgment) rather than what family members want. (4) Ethics committee consultation if unable to resolve. (5)
📋 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 the conversation on "what would the patient want?" (substituted judgment) rather than what family members want. (4) Ethics committee consultation if unable to resolve. (5)
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
DNR ≠ Do Not Treat
DNR only addresses cardiac arrest. All other care continues unless specifically limited.
Never Ask
"Do you want everything?" Instead: explain interventions, ask what outcomes are acceptable.
Conversation Framework
Ask permission → Assess understanding → Explore values → Share prognosis → Recommend → Document.
POLST vs AD
AD = legal document, any time, interpreted. POLST = medical order, serious illness, immediately actionable.
CMO Symptoms
Morphine (pain + dyspnea), lorazepam (anxiety), glycopyrrolate (secretions), haldol (agitation).
Documentation
Code status in EMR. Healthcare proxy identified. Communicate to ALL team members.
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." |
🚨 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
🧪 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.
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.
📋 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.
⚡ Summary
SPIKES
Setting → Perception → Invitation → Knowledge → Emotions → Summary. Framework for bad news.
Pre-Meeting
Align team on prognosis. Identify decision-maker. Book private room. Set agenda.
Key Phrases
"What is your understanding?" "I wish things were different." "I'm worried that..."
Emotions First
NURSE: Name, Understand, Respect, Support, Explore. Address feelings before giving more info.
Silence
Allow silence after bad news. It is therapeutic and necessary for processing. Do not fill it.
Document
Attendees, discussion, decisions, follow-up plan. Update code status. Communicate to team.
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 |
| CXR | Normal | Upper lobe cavitary lesions, infiltrates, hilar LAD, Ghon complex |
| AFB smear | Negative | May be positive (3 sputum samples) |
| Infectious | No | Yes -airborne isolation required |
| PPD/IGRA | Positive | Usually positive (can be negative if immunosuppressed) |
Airborne isolation (negative pressure room, N95 for staff) for ANY suspected active TB until 3 consecutive negative AFB smears collected 8–24h apart.
Extrapulmonary TB
| Site | Presentation | Diagnosis |
|---|---|---|
| TB Meningitis | Subacute headache, cranial nerve palsies, basilar meningitis | 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. |
"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)
- Pyrazinamide = Painful joints (hyperuricemia/gout) + liver Problems
- Ethambutol = Eyes (optic neuritis)
🚨 Management
Active TB: RIPE Therapy
| Drug | Duration | Major Side Effects |
|---|---|---|
| Rifampin (Rifadin) | 6 months | Orange body fluids, hepatotoxicity, drug interactions (CYP450 inducer) |
| Isoniazid (INH) | 6 months | Hepatotoxicity, peripheral neuropathy (give Pyridoxine (Vitamin B6) 25–50 mg daily) |
| Pyrazinamide | 2 months | Hepatotoxicity, hyperuricemia/gout |
| Ethambutol (Myambutol) | 2 months | Optic neuritis -check visual acuity monthly. Red-green color blindness. |
Latent TB Treatment
- Isoniazid (INH) 300 mg daily × 9 months (classic regimen)
- Rifampin (Rifadin) 600 mg daily × 4 months (shorter, preferred)
- INH + Rifapentine (Priftin) weekly × 12 weeks (3HP regimen -DOT)
🧪 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
- CXR -upper lobe infiltrates, cavitary lesions, Ghon/Ranke complex
- 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)
💊 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.
Case 1: Active Pulmonary TB
Patient: 34M immigrant, 3-month cough, night sweats, 15 lb weight loss. CXR: upper lobe cavitation. AFB smear 3+ positive. GeneXpert MTB/RIF positive, rifampin sensitive.
Management:
- Airborne precautions — negative pressure room, N95 for all staff
- Start RIPE therapy: Rifampin (Rifadin) + Isoniazid (INH) + Pyrazinamide (PZA) + Ethambutol (Myambutol) × 2 months, then Rifampin + Isoniazid × 4 months
- Add Pyridoxine (B6) 25–50 mg daily with INH to prevent neuropathy
- DOT (directly observed therapy) mandatory — improves adherence, prevents resistance
- Report to health department — legally required for all active TB cases
- HIV test in all TB patients
Key lesson: GeneXpert confirms TB and rules out rifampin resistance within hours. Start RIPE, isolate, report — do all three same day.
Case 2: Latent TB — Immunosuppressed Patient
Patient: 52F with RA, positive IGRA, no symptoms, normal CXR. About to start Adalimumab (Humira) (anti-TNF biologic).
Management:
- Rule out active disease first — symptom screen + CXR (active TB must be excluded before treating latent)
- Preferred regimen: Rifampin (Rifadin) × 4 months or 3HP — Isoniazid + Rifapentine (Priftin) weekly × 12 doses (directly observed)
- Complete LTBI treatment BEFORE starting biologic — anti-TNF agents profoundly impair granuloma formation, risking TB reactivation
- 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
Latent vs Active
Latent: + PPD/IGRA, no symptoms, normal CXR, not infectious. Active: symptoms, abnormal CXR, infectious.
RIPE Therapy
Rifampin + INH (6 mo) + Pyrazinamide + Ethambutol (2 mo). Always give B6 with INH.
Isolation
Airborne (negative pressure, N95). Until 3 negative AFB smears 8-24h apart.
Side Effects
INH: hepatotoxicity, neuropathy. Rifampin: orange fluids, CYP inducer. Ethambutol: optic neuritis.
Diagnosis
3 sputum AFB smears/cultures. NAAT (GeneXpert) for rapid detection + rifampin resistance.
Always Test
HIV in all TB patients. LFTs at baseline and monthly. Visual acuity if on ethambutol.
High-YieldID
Fungal Infections
Candida (ICU, lines, immunosuppression), Aspergillus (neutropenic, transplant), Cryptococcus (HIV, CD4 < 100), endemic mycoses (Histo, Coccidio, Blasto). Echinocandins for Candida, voriconazole for Aspergillus, amphotericin for severe.
🔍 Overview
Major Fungal Pathogens
| Organism | Risk Factors | Key Features |
|---|---|---|
| Candida | ICU, central lines, TPN, broad-spectrum abx, neutropenia | Candidemia, oral thrush, esophagitis. Remove lines. Echinocandin first-line. |
| Aspergillus | Neutropenia, transplant, chronic steroids, COPD | Invasive pulmonary aspergillosis (IPA). "Halo sign" on CT. Galactomannan antigen. |
| Cryptococcus | HIV (CD4 < 100), transplant | Meningitis -headache, fever. India ink, cryptococcal antigen (CrAg). Elevated opening pressure. |
| Histoplasma | Ohio/Mississippi River Valley, bat/bird guano | Pneumonia ± mediastinal LAD. Urine/serum antigen. Can mimic sarcoidosis. |
| Coccidioides | Southwestern US deserts | "Valley fever." Pneumonia, erythema nodosum, meningitis (if disseminated). |
| PJP (Pneumocystis) | HIV (CD4 < 200), immunosuppression | Bilateral ground-glass opacities. ↑ LDH. TMP-SMX treatment AND prophylaxis. |
🚨 Management
Treatment by Organism
| Infection | First-Line | Duration |
|---|---|---|
| Candidemia | Micafungin (Mycamine) 100 mg IV daily or Caspofungin (Cancidas) 70mg load then 50mg daily | 14 days after first negative blood culture. REMOVE all central lines. |
| Invasive Aspergillus | Voriconazole (Vfend) 6mg/kg IV q12h × 2, then 4mg/kg q12h | 6–12 weeks minimum. Check voriconazole trough levels. |
| Crypto meningitis | Amphotericin B (AmBisome) + Flucytosine (Ancobon) × 2 wk → Fluconazole (Diflucan) | Induction 2 wk → consolidation 8 wk → maintenance 1 yr |
| PJP (moderate-severe) | 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. |
| Peritoneal fluid | Significant if from surgical sample | Treat -intra-abdominal candidiasis. Echinocandin + source control. |
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.
- Histoplasma/Coccidioides urine antigen
- CT chest -halo sign (aspergillus), ground-glass (PJP), cavitary (histo, coccidio)
RoundsRx Licensed Content - Unauthorized Use Prohibited💊 Medications
| Drug Class | Agents | Key Notes |
|---|---|---|
| Echinocandins | Micafungin (Mycamine), Caspofungin (Cancidas), Anidulafungin (Eraxis) | First-line candidemia. NO activity vs Cryptococcus or Mucor. Well tolerated. |
| Azoles | Fluconazole (Diflucan), Voriconazole (Vfend), Itraconazole (Sporanox), Posaconazole (Noxafil) | 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.
Labs: 2/2 blood cultures (PICC and peripheral draw) grow Candida albicans. Creatinine 1.4 (baseline 0.9).
Key Decision Points:
- 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").
Labs: Serum galactomannan 1.8 (positive; threshold ≥0.5). Beta-D-glucan positive. BAL galactomannan 3.2.
Management:
- 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
ICU/lines/TPN. Echinocandin first-line. Remove all central lines. 14 days after clearance.
Aspergillus
Neutropenia/transplant. Voriconazole first-line. Halo sign on CT. Galactomannan antigen.
Crypto
HIV CD4 < 100. Meningitis. CrAg (serum/CSF). Ampho B + flucytosine → fluconazole.
PJP
HIV CD4 < 200. Ground-glass, ↑ LDH. TMP-SMX. Add steroids if PaO₂ < 70.
BDG
Pan-fungal marker. NOT elevated in Crypto or Mucor. Elevated in Candida, Aspergillus, PJP.
Candidemia Workup
Blood cultures q48h, ophthalmology (endophthalmitis), echo (endocarditis), remove lines.
High-YieldNephro
Nephrotic vs Nephritic Syndrome
Nephrotic: massive proteinuria (>3.5g/day), hypoalbuminemia, edema, hyperlipidemia. Nephritic: hematuria, RBC casts, HTN, mild proteinuria, ↓ GFR. The distinction guides workup and differential.
🔍 Overview
Key Distinction
| Feature | Nephrotic Syndrome | Nephritic Syndrome |
|---|---|---|
| Proteinuria | > 3.5 g/day (massive) | < 3.5 g/day (mild-moderate) |
| Hematuria | Absent or mild | Present -dysmorphic RBCs, RBC casts |
| Edema | Severe (periorbital, anasarca) | Mild-moderate |
| Albumin | ↓↓ (< 3 g/dL) | Normal or mildly ↓ |
| Lipids | ↑↑ Hyperlipidemia | Normal |
| Complement | Normal | Low in some (post-strep, lupus, MPGN) |
| BP | Variable | Hypertension |
| GFR | Initially preserved | ↓ (acute kidney injury) |
| Mechanism | Podocyte injury → protein leak | GBM inflammation → blood leak |
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)
- Disease-specific treatment -steroids (MCD), rituximab (MN, FSGS), immunosuppression
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
🧪 Workup
- Urinalysis with microscopy -proteinuria, hematuria, RBC casts (nephritic), fatty casts/oval fat bodies (nephrotic)
- Spot urine protein/creatinine ratio (UPCR) -> 3.5 = nephrotic range
- 24-hour urine protein -gold standard quantification
- BMP -creatinine, eGFR
- Albumin, lipid panel
- Serologies: ANA, dsDNA, complement (C3/C4), ANCA, anti-GBM, PLA2R Ab, hepatitis panel, HIV
- Renal biopsy -usually needed for definitive diagnosis
💊 Medications
| Drug | Dose | Purpose |
|---|---|---|
| Lisinopril (Zestril) | 5–40 mg daily | Reduce proteinuria. First-line for ALL proteinuric kidney disease. |
| Furosemide (Lasix) | 20–80 mg IV/PO | Edema management. May need high doses with hypoalbuminemia. |
| Prednisone (Deltasone) | 1 mg/kg daily × 4–8 wk | Minimal change disease (dramatic response). Taper over weeks. |
| Rituximab (Rituxan) | 375 mg/m² IV | Membranous nephropathy, refractory FSGS, lupus nephritis |
| Cyclophosphamide (Cytoxan) | Varies | ANCA vasculitis, severe lupus nephritis |
📋 On Rounds
Pimp Questions
Why are nephrotic patients hypercoagulable?
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.
📋 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).
Diagnosis: ANCA-associated rapidly progressive glomerulonephritis (RPGN).
Key findings:
- RBC casts — pathognomonic for glomerulonephritis (nephritic pattern)
- Rapidly rising creatinine (1.0 → 2.8) — RPGN is a nephrology emergency
- p-ANCA/MPO positive — microscopic polyangiitis (MPA)
- Renal biopsy: crescentic GN with pauci-immune pattern (few/no immune deposits)
Treatment: Pulse IV methylprednisolone 500–1000 mg x 3 days, then cyclophosphamide (or rituximab). Urgent nephrology consult — delay = irreversible renal loss.
📋 Case 3 — Membranous Nephropathy
Patient: 55F with progressive bilateral lower extremity edema, foamy urine. Labs: albumin 2.1, UPCR 8.2, Cr 1.1, cholesterol 340. PLA2R antibody positive.
Diagnosis: Primary membranous nephropathy.
Key findings:
- 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
Nephrotic
Proteinuria > 3.5g/day, hypoalbuminemia, edema, hyperlipidemia. Podocyte injury.
Nephritic
Hematuria, RBC casts, HTN, ↓ GFR. GBM inflammation. RPGN is an emergency.
#1 Causes
Nephrotic: FSGS (adults), MCD (kids). Nephritic: IgA (#1 worldwide), post-strep (kids).
All Get ACEi
ACEi/ARB reduces proteinuria in ALL proteinuric kidney disease. First-line.
Hypercoagulable
Loss of antithrombin III → renal vein thrombosis, DVT, PE. Anticoagulate if albumin < 2.5.
Complement
Low C3+C4: SLE, cryo. Low C3 only: post-strep, MPGN. Normal: IgA, ANCA, anti-GBM.
High-YieldNephro
Renal Tubular Acidosis
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) | < 5.5 |
| Serum HCO₃⁻ | Can be very low (< 10) | Usually 12–20 (self-limited) | Usually > 15 (mild) |
| Associations | Sjögren, SLE, nephrocalcinosis, kidney stones | Fanconi syndrome, multiple myeloma, carbonic anhydrase inhibitors | Diabetes (#1), ACEi/ARBs, K-sparing diuretics, adrenal insufficiency |
| Treatment | Oral NaHCO₃ 1–2 mEq/kg/day | Oral NaHCO₃ (high doses needed) + thiazide | Fludrocortisone (Florinef), low-K diet, loop diuretics |
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."
- Features: Type 2 RTA + glycosuria (normal blood glucose) + aminoaciduria + phosphaturia (hypophosphatemia/rickets) + uricosuria
- 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
🚨 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.
- Type 4: Treat hyperkalemia first. Fludrocortisone (Florinef) 0.1 mg daily if hypoaldosteronism. Low-potassium diet. Furosemide (Lasix) (increases K⁺ excretion). Discontinue offending drugs (ACEi, K-sparing diuretics, TMP-SMX).
🧪 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
💊 Medications
| Drug | Dose | Type |
|---|---|---|
| Sodium Bicarbonate | 1–2 mEq/kg/day (Type 1); 10–15 mEq/kg/day (Type 2) | Types 1 & 2 |
| Potassium Citrate | 20–40 mEq BID-TID | Type 1 -corrects acidosis AND prevents stones |
| Fludrocortisone (Florinef) | 0.1 mg PO daily | Type 4 -mineralocorticoid replacement |
| Furosemide (Lasix) | 20–40 mg PO daily | Type 4 -enhances K⁺ excretion |
| Hydrochlorothiazide (Microzide) | 12.5–25 mg daily | 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.
📋 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.
Diagnosis: Type 1 (Distal) RTA.
Key findings:
- Cannot acidify urine below 5.5 — urine pH 6.2 confirms distal defect
- Hypokalemia (K 2.8) — classic for Type 1
- Sjögren syndrome — autoimmune cause of Type 1 RTA
Treatment: NaHCO₃ 1–2 mEq/kg/day + KCl supplementation. Monitor for nephrocalcinosis.
📋 Case 2 — Type 4 RTA
Patient: 65M with type 2 diabetes on lisinopril. BMP: K 6.1, HCO₃ 18, AG 10. Urine pH 5.0.
Diagnosis: Type 4 RTA.
Key findings:
- Hyperkalemia (K 6.1) — hallmark of Type 4
- Diabetic nephropathy → hyporeninemic hypoaldosteronism
- ACEi (lisinopril) worsens by further reducing aldosterone
- Can acidify urine (pH 5.0) — distinguishes from Type 1
Treatment: Stop lisinopril, low-K diet, fludrocortisone if persistent hyperkalemia.
📋 Case 3 — Fanconi Syndrome (Type 2 RTA)
Patient: 8-year-old with failure to thrive, rickets, glycosuria with normal blood glucose, aminoaciduria.
Diagnosis: Fanconi syndrome → Type 2 (Proximal) RTA.
Key findings:
- Everything leaking through proximal tubule: glucose, amino acids, phosphate, bicarbonate, uric acid
- 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
Type 1 (Distal)
Cannot secrete H⁺. Urine pH > 5.5. Hypokalemia. Stones/nephrocalcinosis. Low-dose bicarb works.
Type 2 (Proximal)
Cannot reabsorb HCO₃⁻. Fanconi, myeloma. Needs HIGH-dose bicarb + thiazide.
Type 4
Most common. ↓ Aldosterone → hyperkalemia. DM, ACEi, K-sparing diuretics. Fludrocortisone.
Urine AG
Positive = RTA (kidney problem). Negative = GI loss (kidney compensating). "Negative is Normal."
K⁺ Pattern
Types 1&2: hypokalemia. Type 4: HYPERkalemia. This is the key clinical differentiator.
All NAGMA
Check anion gap first (must be normal). Then urine AG and urine pH to classify.
High-YieldRheumatology
PMR & Giant Cell Arteritis
PMR: bilateral shoulder/hip girdle pain and stiffness in elderly. ESR/CRP markedly elevated. Dramatic response to low-dose prednisone. GCA: temporal headache, jaw claudication, vision loss. Emergent steroids -do not wait for biopsy.
🔍 Overview
PMR vs GCA
| Feature | PMR | GCA |
|---|---|---|
| Age | > 50 (mean ~72) | > 50 (mean ~72) |
| Symptoms | Bilateral shoulder/hip girdle pain, morning stiffness > 45 min | New temporal headache, jaw claudication, scalp tenderness, visual changes |
| Feared complication | 15–20% develop GCA | Permanent vision loss (anterior ischemic optic neuropathy) |
| ESR/CRP | ↑↑ (ESR often > 40–50) | ↑↑↑ (ESR often > 50–100) |
| Diagnosis | Clinical + ↑ inflammatory markers + response to steroids | Temporal artery biopsy (gold standard). Temporal artery US. |
| Treatment | Prednisone (Deltasone) 12.5–25 mg daily | 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.
PMR vs GCA Comparison
| Feature | PMR | GCA |
|---|---|---|
| Age | > 50 (mean ~72), women > men | > 50 (mean ~72), women > men |
| Symptoms | Bilateral shoulder/hip girdle pain, morning stiffness > 45 min, difficulty rising from chair | 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)
• 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)
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)
GCA Treatment
- Prednisone (Deltasone) 60 mg daily -immediate start
- If vision threatened: Methylprednisolone (Solu-Medrol) 1g IV daily × 3 days, then oral prednisone
- Slow taper over 1–2 years
- Tocilizumab (Actemra) -IL-6 inhibitor, steroid-sparing agent (GiACTA trial)
- Low-dose aspirin -reduces ischemic complications (visual, stroke)
Steroid Taper Guide
| Condition | Starting Dose | Taper Schedule |
|---|---|---|
| PMR | Prednisone 15–20 mg daily | ↓ 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.
Labs: ESR 88 mm/hr (↑↑), CRP 45 mg/L (↑↑), CK normal, RF negative, anti-CCP negative.
Management:
- Start Prednisone (Deltasone) 15 mg daily
- 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.
Labs: ESR 102 mm/hr (↑↑↑), CRP 68 mg/L, platelets 450k, normocytic anemia (Hgb 11.2).
Management:
- Start Prednisone (Deltasone) 60 mg daily IMMEDIATELY -do not wait for biopsy
- Schedule temporal artery biopsy within 1–2 weeks (steroids do not affect biopsy results for up to 2 weeks)
- Start aspirin 81 mg daily (reduces ischemic complications)
- Biopsy result: Granulomatous inflammation with giant cells, fragmented internal elastic lamina → confirms GCA
- 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
PMR
Age > 50, bilateral shoulder/hip pain, morning stiffness, ↑ ESR/CRP. Prednisone 12.5-25mg. Dramatic response.
GCA
Temporal headache, jaw claudication, vision loss. Prednisone 60mg. IV methylpred if vision threatened.
Vision Loss
Anterior ischemic optic neuropathy. IRREVERSIBLE. Start steroids BEFORE biopsy. Do not wait.
Biopsy
Temporal artery biopsy is gold standard. Skip lesions → can be negative. Treat empirically if high suspicion.
Tocilizumab
IL-6 inhibitor (Actemra). Steroid-sparing in GCA (GiACTA trial). SC weekly.
PMR → GCA
15-20% of PMR patients develop GCA. Monitor for headache, visual symptoms, jaw claudication.
High-YieldEndocrine
Hypoparathyroidism
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 |
| Autoimmune | Autoimmune polyendocrine syndrome type 1 (APS-1) |
| Hypomagnesemia | Mg < 1.0 → impaired PTH secretion AND PTH resistance. Fix Mg first! |
| Infiltrative | Hemochromatosis, Wilson disease, metastatic cancer |
| DiGeorge syndrome | 22q11 deletion -absent parathyroids + thymic aplasia |
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 |
| DiGeorge syndrome | 22q11.2 deletion → absent/hypoplastic parathyroids | Congenital: cardiac defects, thymic aplasia, characteristic facies |
| Hypomagnesemia (functional) | Mg < 1.0 → impaired PTH secretion AND end-organ PTH resistance | PTH is low despite low calcium; calcium won't correct until Mg repleted |
| Infiltrative (hemochromatosis, Wilson) | Iron/copper deposition in parathyroid glands destroys tissue | Look for liver disease, skin changes; check ferritin, ceruloplasmin |
Mnemonic -CHVOSTEK for Signs of Hypocalcemia:
Chvostek sign (facial twitch on tapping) · Hyperreflexia · Vitals (prolonged QT interval) · Obtundation/seizures · Spasm (Trousseau sign -carpopedal spasm) · Tetany · Excitability (neuromuscular irritability) · Kidney stones (chronic hypercalciuria → nephrocalcinosis)
Chvostek sign (facial twitch on tapping) · Hyperreflexia · Vitals (prolonged QT interval) · Obtundation/seizures · Spasm (Trousseau sign -carpopedal spasm) · Tetany · Excitability (neuromuscular irritability) · Kidney stones (chronic hypercalciuria → nephrocalcinosis)
🚨 Management
Acute Symptomatic Hypocalcemia
- Calcium gluconate 1–2g IV over 10–20 min (preferred over CaCl for peripheral IV -less tissue necrosis)
- Follow with continuous infusion: 0.5–1.5 mg/kg/hr of elemental calcium
- Correct magnesium if low -MgSO₄ 2g IV
- Continuous telemetry -monitor QTc
Chronic Management
- Calcium Carbonate (Tums) 1–3g elemental calcium daily in divided doses
- Calcitriol (Rocaltrol) 0.25–2 mcg daily -active vitamin D (PTH normally activates vitamin D; without PTH, must give active form)
- Natpara (recombinant PTH) -for refractory cases not controlled with calcium/calcitriol
Acute vs Chronic Management
| Setting | Treatment | Details |
|---|---|---|
| Acute | IV Calcium Gluconate | 1–2g IV over 10 min; preferred for peripheral IV (less tissue necrosis) |
| Continuous calcium drip | 0.5–1.5 mg/kg/hr elemental calcium; titrate to ionized Ca q4–6h | |
| Cardiac monitoring | Continuous telemetry -prolonged QTc → torsades risk; correct Mg simultaneously | |
| Chronic | Calcitriol (Rocaltrol) | 0.25–2 mcg daily -active vitamin D (bypasses PTH-dependent activation) |
| Calcium Carbonate (Tums) | 1–3g elemental calcium daily in divided doses with food | |
| Thiazide diuretics | Reduce urinary calcium excretion → prevent nephrocalcinosis/kidney stones | |
| Natpara (recombinant PTH) | PTH replacement for refractory cases; reduces calcium/calcitriol requirements |
🧪 Workup
- Serum calcium -low (correct for albumin: add 0.8 per 1g albumin below 4)
- Ionized calcium -most accurate
- PTH -low or inappropriately normal (confirms hypoparathyroidism)
- Phosphate -elevated (PTH normally promotes PO₄ excretion)
- 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
- Immunology consult (thymic aplasia → T-cell deficiency)
- Lifelong calcium and calcitriol replacement -absent parathyroids will not recover
Key lesson: DiGeorge syndrome = absent parathyroids + thymic aplasia. Seizures in DiGeorge should trigger immediate calcium check. These patients need lifelong replacement -no chance of parathyroid recovery.
📋 Case 3 — Chronic Hypoparathyroidism with Nephrocalcinosis
Patient: 62F with chronic hypoparathyroidism (post-thyroidectomy 8 years ago), on calcitriol 1 mcg BID + calcium carbonate 1.5g TID. Presents with flank pain. CT shows bilateral nephrocalcinosis.
Labs: Total Ca 9.2 (normal on replacement), 24h urine Ca 420 mg (elevated, normal < 300), creatinine 1.4 (baseline 0.9), PO₄ 4.8.
Problem: Without PTH, kidneys cannot reabsorb calcium → chronic hypercalciuria → nephrocalcinosis → renal damage despite normal serum calcium.
Management:
- Add hydrochlorothiazide 25 mg daily -thiazide diuretics enhance renal calcium reabsorption, reducing urinary calcium
- Reduce calcitriol dose to 0.5 mcg BID (lower target serum Ca to low-normal 8.0–8.5)
- Consider Natpara (recombinant PTH) -PTH replacement restores physiologic calcium handling, reduces urinary calcium
- 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
#1 Cause
Post-thyroidectomy/parathyroidectomy. Iatrogenic parathyroid removal/damage.
Lab Pattern
↓ Ca, ↓ PTH, ↑ PO₄. Always check Mg -low Mg causes functional hypoPTH.
Acute Rx
Calcium gluconate 1-2g IV (peripheral safe). CaCl via central only. Telemetry for QTc.
Chronic Rx
Oral calcium carbonate + calcitriol (active vitamin D -bypasses need for PTH activation).
Fix Mg First
Mg < 1.0 → impaired PTH secretion AND resistance. Calcium won't correct without Mg.
Monitoring
Ionized Ca, QTc (torsades risk), 24h urine Ca (nephrocalcinosis), renal US annually.
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 toxoid | 0.5 mL IM | If not up to date |
📋 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
Rule of 9s
Head 9%, each arm 9%, anterior trunk 18%, posterior 18%, each leg 18%, perineum 1%.
Parkland Formula
4 mL × kg × %BSA. Half in first 8h (from burn time), half over next 16h. LR, not NS.
Urine Output
Primary resuscitation target: 0.5-1 mL/kg/hr adults, 1 mL/kg/hr children.
Airway
Intubate EARLY if inhalation injury suspected. Singed hair, stridor, carbonaceous sputum.
Escharotomy
Circumferential full-thickness burns → compartment syndrome. Bedside incision through eschar.
CO Poisoning
COHb levels (SpO₂ unreliable). 100% O₂ NRB. Hyperbaric if severe.
EmergentEM
Hypothermia & Drowning
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.
🔍 Overview
Classification
| Severity | Temp Range | Key Features | Treatment |
|---|---|---|---|
| Mild | 32–35°C | Shivering, tachycardia, vasoconstriction, altered judgment | Passive external rewarming (blankets, warm room). Remove wet clothing. |
| Moderate | 28–32°C | Shivering stops, confusion→stupor, bradycardia, Osborn (J) waves on ECG, atrial fibrillation | 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.
🚨 Management
Rewarming Strategies
| Method | Indication | Rate of Rewarming |
|---|---|---|
| Passive external (blankets, warm room, remove wet clothes) | Mild hypothermia (32–35°C). Patient can generate heat via shivering. | 0.5–2°C/hr |
| Active external (Bair Hugger, warm packs to axillae/groin) | Moderate hypothermia (28–32°C). Shivering lost — patient cannot self-rewarm. | 1–2°C/hr |
| Warm IV fluids (NS/LR at 40–42°C) | 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)
- ECG -Osborn (J) waves, prolonged intervals, atrial fibrillation, VF
- ABG -pH interpretation complex (use temperature-corrected values)
- BMP -hyperkalemia (cell lysis), hypoglycemia
- CBC, coags (hypothermia causes coagulopathy)
- Lactate
- 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.
Labs: K⁺ 5.8, glucose 48 (hypoglycemic), lactate 3.2, TSH pending, cortisol pending.
Management:
- 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
Classification
Mild 32-35°C (shivering). Moderate 28-32°C (no shivering, J waves). Severe <28°C (VF, coma).
Golden Rule
"No one is dead until warm and dead." Do not declare death until core temp ≥ 32°C.
Rewarming
Mild: passive. Moderate: Bair Hugger, warm IV. Severe: ECMO (gold standard for arrest).
Cardiac Arrest
Continue CPR. Max 3 shocks if <30°C, defer more until ≥30°C. Withhold meds until ≥30°C.
K⁺ Prognostic
K⁺ > 12 mEq/L = non-survivable (massive cell lysis). Serial K⁺ guides resuscitation.
Afterdrop
Core temp drops further after rescue -cold peripheral blood returns to core. Rewarm core first.
EmergentHeme/Onc
Hyperviscosity Syndrome
Elevated serum viscosity from excess immunoglobulins (Waldenström IgM most common) or extreme leukocytosis/polycythemia. Classic triad: bleeding, visual changes, neurologic symptoms. Emergent plasmapheresis.
🔍 Overview
Causes
| Cause | Details |
|---|---|
| Waldenström macroglobulinemia | #1 cause. IgM paraprotein -large pentamer is most viscous. Symptoms at IgM > 3 g/dL. |
| Multiple myeloma | Less common (IgA > IgG -IgA polymerizes). ~2–5% of MM cases. |
| Leukostasis | WBC > 100K (AML) or > 200–300K (CLL/ALL). White cell plugging in microvasculature. |
| Polycythemia vera | Hct > 60–65%. RBC sludging. |
Classic Triad
- Mucosal bleeding -epistaxis, gingival bleeding (paraprotein interferes with platelet function and clotting factors)
- Visual changes -blurred vision, "sausage-link" retinal veins on fundoscopy, retinal hemorrhages
- 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 |
| Visual Changes | Blurred vision, diplopia, visual loss. Fundoscopy: "sausage-link" retinal veins (alternating dilated/constricted segments), Roth spots, retinal hemorrhages (flame-shaped), papilledema, cotton-wool spots | Hyperviscous blood distends retinal veins and causes stasis → retinal ischemia and hemorrhage |
| Neurologic Symptoms | Headache, dizziness, vertigo, confusion, somnolence, obtundation, hearing loss, ataxia, stroke, coma | Cerebral hypoperfusion from sludging in cerebral microvasculature; can progress to frank infarction |
Diagnostic Workup
| Test | Expected Finding | Significance |
|---|---|---|
| Serum viscosity | Normal: 1.4–1.8 cP. Symptomatic: > 4 cP. Emergency: > 5–6 cP | Definitive measurement. Must be ordered specifically (not part of routine labs). |
| SPEP / Immunofixation | M-spike on electrophoresis; immunofixation identifies isotype (IgM, IgA, IgG) | Identifies the paraprotein. Large M-spike correlates with viscosity. |
| UPEP (24-hr urine) | Bence Jones protein (free light chains) | Supports myeloma diagnosis; assesses renal light-chain burden. |
| Quantitative immunoglobulins | Markedly elevated IgM (> 3 g/dL) in Waldenström; elevated IgA or IgG in myeloma | IgM > 3 g/dL almost always causes symptoms. Other Ig levels may be suppressed. |
| Fundoscopic exam | "Sausage-link" retinal veins, Roth spots, flame hemorrhages, papilledema | Pathognomonic findings. Should be performed on ALL suspected cases. Findings resolve after plasmapheresis. |
| CBC with peripheral smear | Rouleaux formation (RBCs stacked like coins), anemia, possible leukocytosis | Rouleaux is classic. Anemia may be dilutional or from marrow infiltration. |
| Coagulation studies | Prolonged PT/PTT, prolonged thrombin time | Paraprotein interferes with clotting factors and fibrin polymerization. |
| BMP, LDH, uric acid | Elevated LDH, elevated uric acid, possible renal insufficiency | Assess for tumor lysis risk and end-organ damage. |
Mnemonic -VISCOUS (Hyperviscosity Syndrome):
Vision changes (blurred vision, "sausage-link" veins, Roth spots) · Immunoglobulin (IgM most common -pentamer) · Sludging of blood (hypoperfusion, microvasculature) · Coagulopathy / bleeding (epistaxis, mucosal, platelet dysfunction) · Obtundation / neuro symptoms (headache, confusion, coma) · Underlying cause (Waldenström #1, myeloma, leukostasis) · Serum viscosity > 4 cP (emergency > 5–6 cP)
Vision changes (blurred vision, "sausage-link" veins, Roth spots) · Immunoglobulin (IgM most common -pentamer) · Sludging of blood (hypoperfusion, microvasculature) · Coagulopathy / bleeding (epistaxis, mucosal, platelet dysfunction) · Obtundation / neuro symptoms (headache, confusion, coma) · Underlying cause (Waldenström #1, myeloma, leukostasis) · Serum viscosity > 4 cP (emergency > 5–6 cP)
Clinical Examples
📋 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.
Labs: Serum viscosity 8.2 cP (markedly elevated). IgM 5.8 g/dL. CBC shows rouleaux formation. Hgb 9.2.
Action:
- 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.
Labs: Serum viscosity 5.1 cP. IgA 6.2 g/dL (polymerized). BMP shows Cr 2.1 (baseline 1.0). Peripheral smear shows rouleaux.
Action:
- 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)
- Quantitative immunoglobulins
- Fundoscopic exam -"sausage-link" veins, papilledema, retinal hemorrhages
- BMP, LDH, uric acid
- 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
#1 Cause
Waldenström (IgM pentamer). Also: myeloma (IgA), leukostasis (WBC >100K), polycythemia.
Classic Triad
Mucosal bleeding + visual changes (sausage-link veins) + neurologic symptoms.
Treatment
Plasmapheresis (paraprotein). Leukapheresis + hydroxyurea (leukostasis). Phlebotomy (PV).
Do NOT Transfuse
No pRBC until viscosity reduced -worsens sludging → stroke/MI risk.
Fundoscopy
"Sausage-link" retinal veins, papilledema, retinal hemorrhages. Pathognomonic.
Viscosity Levels
Normal 1.4-1.8 cP. Symptoms >4 cP. Emergency >5-6 cP.
High-YieldRheumatology
Dermatomyositis & Polymyositis
Inflammatory myopathies causing proximal muscle weakness. DM has characteristic skin findings (heliotrope rash, Gottron papules). Elevated CK. Associated with malignancy (DM). EMG and muscle biopsy confirm diagnosis. Steroids first-line.
🔍 Overview
Dermatomyositis vs Polymyositis
| Feature | Dermatomyositis | Polymyositis |
|---|---|---|
| Skin findings | Heliotrope rash (purple eyelid discoloration), Gottron papules (papules over MCP/PIP/knuckles), V-sign, shawl sign, mechanic's hands | None |
| Muscle weakness | Proximal, symmetric, progressive | Proximal, symmetric, progressive |
| Histology | Perimysial inflammation, perifascicular atrophy | Endomysial inflammation, CD8+ T cells invading fibers |
| Malignancy | Strong association -screen for ovarian, lung, breast, GI, lymphoma | Weaker association |
| Antibodies | Anti-Mi-2, anti-MDA5, anti-TIF1-γ (malignancy-associated) | Anti-Jo-1 (antisynthetase syndrome: ILD, arthritis, mechanic's hands) |
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. |
| Pattern | ASYMMETRIC, distal + proximal. Finger flexors, wrist flexors, quadriceps ("Can't grip, can't walk"). |
| CK | Mildly elevated or normal |
| Key feature | Does NOT respond to immunosuppression (unlike DM/PM) |
| Histology | Endomysial inflammation + rimmed vacuoles + amyloid deposits |
| Treatment | No effective treatment. PT/OT. IVIG may help swallowing. |
Skin Findings in Detail (Dermatomyositis)
- Heliotrope rash: Purple/lilac discoloration of 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.
- V-sign: Erythema over anterior neck/chest in V-distribution.
- Shawl sign: Erythema over upper back and shoulders.
- Mechanic's hands: Rough, cracked, hyperkeratotic skin on radial side of fingers. Associated with antisynthetase syndrome.
- Holster sign: Erythema over lateral thighs.
- Periungual erythema: Dilated nailfold capillaries.
- Calcinosis cutis: Calcium deposits under skin, more common in juvenile DM.
Mnemonic: HELIOGRAMS
Heliotrope rash, Erythema (V-sign), Limbs (Gottron), Interstitial lung disease, Other autoimmune, Gottron papules, Raynaud, Arthritis, Mechanic's hands, Shawl sign
🚨 Management
Treatment
- First-line: Prednisone (Deltasone) 1 mg/kg/day × 4–6 weeks, then taper
- Steroid-sparing: Methotrexate (Trexall) or Azathioprine (Imuran)
- Refractory: Rituximab (Rituxan), IVIG, Mycophenolate (CellCept)
- ILD management: If antisynthetase syndrome -mycophenolate, rituximab, or cyclophosphamide
- Physical therapy -maintain function during and after treatment
- Malignancy screening -age-appropriate, especially in DM
📋 Case 1 — Classic Dermatomyositis
Patient: 42F presents with progressive proximal weakness × 2 months, cannot climb stairs or lift arms overhead. Purple discoloration of eyelids, papules over knuckles. CK 8,500.
Action:
- Classic dermatomyositis. Heliotrope rash + Gottron papules + proximal weakness + elevated CK.
- Order: Myositis-specific antibodies (including anti-TIF1-γ), EMG, MRI thighs, age-appropriate malignancy screening.
- Start prednisone 1 mg/kg/day.
- Anti-TIF1-γ positivity → intensive cancer screening: CT chest/abdomen/pelvis, mammogram, colonoscopy, pelvic exam.
- PFTs at baseline for ILD screening.
📋 Case 2 — Antisynthetase Syndrome with ILD
Patient: 58F with DM, anti-Jo-1 positive. Develops progressive dyspnea, dry cough. PFTs show restrictive pattern. HRCT: ground-glass opacities, NSIP pattern.
Diagnosis: Antisynthetase syndrome with ILD.
Action:
- ILD is the main driver of mortality in antisynthetase syndrome -not the myopathy.
- Treatment: Steroids + mycophenolate or rituximab for ILD.
- Avoid methotrexate (can cause drug-induced ILD).
- Serial PFTs q3–6 months to monitor progression.
- Look for other features: mechanic's hands, Raynaud, arthritis, fever.
📋 Case 3 — Inclusion Body Myositis
Patient: 72M with 2-year history of progressive difficulty opening jars, frequent falls. Asymmetric weakness, finger flexor weakness, quadriceps atrophy. CK 450 (mildly elevated). Failed 6-month trial of prednisone.
Biopsy: Rimmed vacuoles.
Diagnosis: Inclusion body myositis.
Action:
- No effective immunosuppressive treatment -IBM does not respond to steroids, MTX, or azathioprine.
- PT/OT for functional maintenance and fall prevention.
- Swallowing evaluation -dysphagia is common. IVIG may help swallowing.
- Key distinguishing features: age >50, asymmetric, distal involvement (finger flexors), quadriceps atrophy, failed immunosuppression, rimmed vacuoles on biopsy.
🧪 Workup
- CK -elevated (usually > 10× normal). Primary marker of muscle damage.
- Aldolase -elevated (more specific for muscle, also elevated)
- Myositis-specific antibodies -Anti-Jo-1, anti-Mi-2, anti-MDA5, anti-SRP, anti-TIF1-γ
- EMG -myopathic pattern (short, small, polyphasic motor units, fibrillation potentials)
- MRI of thighs -STIR sequences show edema in affected muscles. Can guide biopsy site.
- Muscle biopsy -gold standard for diagnosis and classification
- PFTs -ILD screening (anti-Jo-1)
- Malignancy screening -CT, mammogram, colonoscopy
💊 Medications
| Drug | Dose | Role |
|---|---|---|
| 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. |
| IVIG | 2 g/kg over 2–5 days monthly | Refractory cases, especially DM |
| Rituximab (Rituxan) | 375 mg/m² × 4 weekly | Refractory myositis, antisynthetase-associated ILD |
📋 On Rounds
Pimp Questions
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
DM vs PM
DM: heliotrope rash, Gottron papules, malignancy association. PM: no skin findings, endomysial CD8+ cells.
Key Lab
CK elevated (often >10× normal). Aldolase also elevated. Myositis-specific antibodies.
Diagnosis
EMG (myopathic pattern), MRI thighs (edema on STIR), muscle biopsy (gold standard).
Treatment
Prednisone 1mg/kg first-line. Steroid-sparing: MTX or azathioprine. Refractory: rituximab, IVIG.
Malignancy
DM strongly associated. Anti-TIF1-γ = malignancy-associated. Screen: CT, mammogram, colonoscopy.
Antisynthetase
Anti-Jo-1. ILD + myopathy + mechanic's hands + arthritis. ILD drives prognosis.
EssentialPalliative
Prognostication Tools
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. |
| APACHE II/IV | ICU patients | ICU mortality prediction. Higher score = higher mortality. |
| MELD score | Liver disease | 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.
🚨 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)
Common Prognostic Time Frames
| Time Frame | Clinical Indicators |
|---|---|
| Months | Declining functional status, weight loss, increasing symptoms, frequent hospitalizations |
| Weeks | Bed-bound most of 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/mottled extremities, mandibular breathing |
🧪 Workup
Assessment Components
- Functional status -PPS, Karnofsky, ECOG performance status
- Nutritional status -weight loss trajectory, BMI, intake history (albumin reflects inflammation, NOT nutrition per ASPEN 2021)
- Disease-specific markers -tumor markers, MELD, NYHA class, eGFR trajectory
- Hospitalization frequency -readmissions suggest declining trajectory
- Symptom burden -increasing symptom load suggests progression
- Patient/family understanding and wishes
💊 Medications
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.
⚡ Summary
Surprise Question
"Would I be surprised if they died in 12 months?" If no → palliative discussion. Screening tool.
PPS
Palliative Performance Scale 0-100%. ≤50% → ~6mo median. ≤30% → days to weeks.
Physician Bias
Physicians overestimate survival 3-5×. Use validated tools. Communicate in ranges.
Time Frames
Months: declining function. Weeks: bed-bound, minimal intake. Days: mottling, Cheyne-Stokes.
Communication
Ask permission. Use ranges. "I hope for the best but worry..." Acknowledge uncertainty.
Disease-Specific
MELD (liver), Seattle Model (HF), APACHE (ICU), PPI (cancer). Each has validated data.
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
- Increased viscosity — contrast increases tubular fluid viscosity → sluggish flow → prolonged tubular exposure to toxin
- Result: Acute tubular necrosis (ATN) pattern — muddy brown granular casts, elevated FeNa
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. |
| Intra-arterial contrast (cardiac cath, angiography) | HIGHER risk | 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. The landmark AMACING trial (2017) showed that in patients with eGFR 30–59, prophylactic IV hydration provided NO benefit over no prevention. The PRESERVE trial (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.
- Minimize contrast volume -use lowest effective dose
- 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 trial: NOT superior to NS. Use NS instead. |
| N-Acetylcysteine (Mucomyst) | 600–1200 mg PO BID × 2 days | No longer recommended. ACT and PRESERVE trials 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. The ACT trial (2011) and PRESERVE trial (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
#1 Risk Factor
CKD (eGFR < 30). Diabetes + CKD = highest risk. DM alone is NOT significant risk.
Prevention
IV NS 1 mL/kg/hr × 6-12h before and after. Only proven intervention.
NAC
No longer recommended. ACT and PRESERVE trials showed no benefit over NS alone.
Metformin
Hold 48h AFTER contrast (not before). Resume when Cr stable. Risk: lactic acidosis if AKI.
Don't Delay
CIN risk is overestimated. Do NOT withhold indicated imaging -missed diagnosis is more dangerous.
Course
Self-limited. Cr peaks day 3-5, returns to baseline 7-14 days. Rarely needs dialysis.
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.
Microbiology
- Mild / acute: Gram-positive cocci dominate -S. aureus (including MRSA), Streptococcus spp.
- Moderate-severe / chronic: Polymicrobial -add gram-negatives (E. coli, Proteus, Klebsiella) and anaerobes (Bacteroides, Peptostreptococcus)
- MRSA risk factors: Prior MRSA, recent hospitalization, hemodialysis, prior antibiotics, nasal colonization
- 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.
Imaging
| Modality | When to Order | Key Findings | Limitations |
|---|---|---|---|
| X-ray (plain film) | First-line, all patients | Soft tissue gas, foreign body, cortical erosion, periosteal reaction | 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
- Infectious disease -moderate-severe infections, osteomyelitis, MRSA/MDR organisms, treatment failures
- Endocrinology -if HbA1c > 9% or uncontrolled glycemia
🚨 Management
Management by Severity
Mild (IDSA Grade 2) -Outpatient
- Oral antibiotics targeting gram-positives (Staph, Strep)
- Amoxicillin-Clavulanate (Augmentin) 875/125 mg PO BID -covers MSSA, Strep, anaerobes
- If MRSA risk: TMP-SMX (Bactrim) DS BID + Cephalexin (Keflex) 500 mg QID (TMP-SMX alone has gaps in Strep coverage)
- Wound care: sharp debridement of necrotic tissue, moist wound environment
- Offloading: non-weight-bearing or therapeutic footwear
- Follow-up in 48-72 hours to assess response. If worsening or no improvement → escalate to inpatient.
- Duration: 1-2 weeks
Moderate (IDSA Grade 3) -Inpatient
- Hospitalize for IV antibiotics, surgical evaluation, vascular assessment
- Ampicillin-Sulbactam (Unasyn) 3g IV q6h -covers gram-positives, gram-negatives, anaerobes
- OR Piperacillin-Tazobactam (Zosyn) 3.375g IV q6h if Pseudomonas risk (water exposure, failed prior therapy)
- Add Vancomycin (Vancocin) if MRSA risk factors present
- Surgical evaluation: debridement, I&D of abscesses, bone biopsy if osteomyelitis suspected
- Vascular assessment: ABI/TBI → vascular surgery consult if abnormal
- IV-to-oral step-down when clinically improving, adequate source control, and susceptibilities known OVIVA, 2019
- Duration: 2-3 weeks (soft tissue only); 6 weeks if osteomyelitis
Severe (IDSA Grade 4) -Emergent
- Urgent surgical debridement -do not delay for imaging
- Broad-spectrum IV: Vancomycin (Vancocin) + Piperacillin-Tazobactam (Zosyn) 4.5g IV q6h
- OR Vancomycin (Vancocin) + Meropenem (Merrem) 1g IV q8h if MDR risk
- ICU admission if septic (hemodynamic instability, organ dysfunction)
- Blood cultures, lactate, aggressive fluid resuscitation
- 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-resection IDSA 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 | MSSA, Strep, anaerobes | 1–2 weeks | First-line for most mild DFI without MRSA risk |
| Mild + MRSA risk | TMP-SMX (Bactrim) DS BID + Cephalexin (Keflex) 500 mg QID | MRSA, MSSA, Strep | 1–2 weeks | TMP-SMX alone has Strep gap -add cephalexin |
| Moderate | Ampicillin-Sulbactam (Unasyn) 3g IV q6h | Gram-pos, gram-neg, anaerobes | 2–3 weeks | 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.
Bedside assessment:
- Probe-to-bone test: sterile probe contacts hard, gritty surface → POSITIVE (PPV ~89%).
- Erythema 3 cm → moderate infection (IDSA grade 3).
- Pedal pulses: dorsalis pedis faint, posterior tibial absent → order ABI.
Workup: ESR 82 (> 70 → high specificity for osteo). X-ray: cortical erosion 5th metatarsal head. MRI: bone marrow edema with rim enhancement → confirms osteomyelitis. ABI 0.6 → significant PAD.
Management:
- Admit. Ampicillin-Sulbactam (Unasyn) 3g IV q6h + Vancomycin (Vancocin) (MRSA risk)
- 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).
Management:
- Fluid resuscitation: 30 mL/kg LR. Blood cultures × 2.
- 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. |
| Blood glucose | AC/HS or q6h | < 180 mg/dL. Hyperglycemia impairs wound healing + neutrophil function. |
| Vancomycin level | Before 4th dose or per protocol | AUC/MIC 400–600. Troughs 15–20 mcg/mL (traditional). Monitor renal function. |
| Renal function (BMP) | q48–72h on nephrotoxic abx | Vancomycin, aminoglycosides, contrast dye → monitor Cr closely. |
⚡ Summary
One-Screen Summary
Classification
IDSA 1-4: uninfected → mild (erythema < 2 cm) → moderate (> 2 cm, deep) → severe (SIRS/sepsis). Classification drives management.
Probe-to-Bone
PPV ~89% for osteomyelitis. Do on every DFI. Positive LR ~6. If positive → order MRI. Simple, bedside, 10 seconds.
Mild (Outpatient)
Augmentin PO or TMP-SMX + cephalexin (if MRSA risk). 1-2 weeks. Follow-up 48-72h.
Moderate-Severe
Unasyn or Zosyn IV ± vancomycin. Severe: vanco + Zosyn/meropenem. Surgical eval for debridement.
Osteomyelitis
MRI gold standard. ESR > 70 specific. Bone biopsy for culture. 6 wks abx (2-4 wks if resected). IV-to-oral OK (OVIVA).
Vascular
ABI/TBI assessment. ABI < 0.5 or TBI < 0.4 = revascularize. Ischemic foot won't heal regardless of antibiotics.
Cultures
Deep tissue only. NEVER surface swabs -grow colonizers, not pathogens. Bone biopsy for osteo.
Triad for Success
Antibiotics + surgical debridement + vascular perfusion. Missing any one = treatment failure.
📄 One Pager
Infectious Disease · One Pager
Diabetic Foot Infection
Neuropathy + ischemia + hyperglycemia = ulcer + infection. Classify by IDSA severity. Probe every wound for bone. Triad: antibiotics + surgery + vascular perfusion.
🧪 Workup
- Probe-to-bone on every wound (PPV ~89%)
- Deep tissue culture (NOT surface swab)
- X-ray first, MRI for osteo (sens ~90%)
- ESR > 70 = high specificity for osteo
- ABI/TBI for vascular assessment
- CBC, BMP, CRP, HbA1c
📊 IDSA Classification
- Mild (2): Erythema < 2 cm, superficial
- Moderate (3): Erythema > 2 cm, deep, no SIRS
- Severe (4): SIRS/sepsis, limb-threatening
- Limb-threatening: gas, crepitus, wet gangrene
- Osteomyelitis: probe-to-bone +, ESR > 70
🚨 Management by Severity
1
Mild: Augmentin PO or TMP-SMX + cephalexin. Outpatient. 1-2 wks.
2
Moderate: Unasyn IV ± vanco. Zosyn if Pseudomonas risk. Surgery eval. 2-3 wks.
3
Severe: Vanco + Zosyn/meropenem. Emergent debridement. ICU if septic.
4
Osteo: Bone biopsy + 6 wks abx. Post-resection: 2-4 wks. IV→PO OK (OVIVA).
5
Vascular: ABI < 0.5 / TBI < 0.4 → revascularize before expecting healing.
6
Wound: Debride, offload (TCC), moist dressing, glucose < 180.
💊 Key Drugs
Augmentin875/125 PO BID
Unasyn3g IV q6h
Zosyn3.375-4.5g IV q6h
Vancomycin15-20 mg/kg IV q8-12h
Ertapenem1g IV daily (OPAT)
Meropenem1g IV q8h (severe)
📊 Duration
- Mild: 1-2 weeks
- Moderate: 2-3 weeks
- Severe: 2-4 weeks
- Osteo (medical): 6 weeks
- Osteo (post-resection): 2-4 wks
⚠️ Pitfalls
- Surface swab cultures (colonizers!)
- Ignoring vascular assessment
- Falsely elevated ABI (calcification)
- Delaying surgery for imaging
- No offloading plan
🏥 Consults
- Podiatry: wound care, offloading
- Vascular surgery: if PAD / ischemia
- Ortho/Plastics: debridement, resection
- ID: moderate-severe, osteo, MDR
🎓 Key Trials
- OVIVA 2019: Oral non-inferior to IV for bone/joint infections
- SIDESTEP 2005: Ertapenem non-inferior to pip-tazo for DFI
- IDSA 2012: DFI classification and management guidelines
EssentialPalliative
Non-Opioid Symptom Management
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
Symptom-by-Symptom Overview
| Symptom | First-Line Non-Opioid | Second-Line | Key Principle |
|---|---|---|---|
| Pain | Acetaminophen (Tylenol) 1g q6h scheduled, Ibuprofen (Advil) 400–600mg q6h | Gabapentin (Neurontin), Lidocaine 5% patch, Ketorolac (Toradol) IV, Cyclobenzaprine (Flexeril) | Scheduled acetaminophen reduces opioid use by 30%. WHO ladder modified for non-opioid focus. |
| Nausea/Vomiting | Ondansetron (Zofran) 4mg IV/PO q6h | Metoclopramide (Reglan) 10mg, Prochlorperazine (Compazine) 10mg, Scopolamine patch | Match antiemetic to mechanism: 5-HT3 for chemo/post-op, dopamine antagonist for gastroparesis, anticholinergic for vestibular. |
| Dyspnea | Fan to face, upright positioning, oxygen only if SpO2 < 90% | Low-dose morphine 2mg IV q2h (exception — treats air hunger centrally), Lorazepam (Ativan) 0.5mg for anxiety component | Fan across trigeminal V2 distribution suppresses breathlessness centrally. More effective than O2 in non-hypoxic patients. |
| Constipation | Senna (Senokot) 2 tabs BID + PEG 3350 (MiraLAX) 17g daily | Bisacodyl (Dulcolax) 10mg PR, Methylnaltrexone (Relistor), Naloxegol (Movantik) 25mg PO daily | Stimulant laxative (senna) + osmotic (PEG) is the evidence-based regimen. Docusate is no better than placebo AGA-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. |
| Pruritus | Hydroxyzine (Vistaril) 25mg PO q6h, moisturizers | Diphenhydramine (Benadryl) 25mg (use cautiously — anticholinergic), Cholestyramine (Questran) for cholestatic pruritus | Identify cause: uremic → gabapentin; cholestatic → cholestyramine/naltrexone; histamine-mediated → antihistamines. |
| Hiccups | Chlorpromazine (Thorazine) 25–50mg PO/IV | Baclofen (Lioresal) 5–10mg TID, Gabapentin (Neurontin) 300mg TID | Chlorpromazine is the only FDA-approved drug for hiccups. Baclofen and gabapentin are evidence-based alternatives. |
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
- Nausea: ginger ale, small frequent meals, acupressure wristbands (P6 point), aromatherapy (peppermint oil)
- Dyspnea: fan to face, upright/tripod positioning, pursed lip breathing, cool room temperature, reduce anxiety
- Insomnia: minimize nighttime vitals/labs, earplugs/eye mask, limit caffeine after noon, consistent wake time, reduce ambient light
- Constipation: ambulation, adequate hydration, fiber supplementation (if not obstructed), abdominal massage
- Pruritus: cool compresses, moisturizers, oatmeal baths, keep nails short, loose-fitting clothing
🧪 Workup
Symptom Assessment Tools
| Tool | Application | Details |
|---|---|---|
| Numeric Rating Scale (NRS) | Pain (alert patients) | 0–10 scale. Most widely used. Document at rest AND with movement. |
| Wong-Baker FACES | Pain (non-verbal, pediatric, cognitive impairment) | Visual faces scale. Useful when patients cannot verbalize a number. |
| BPS (Behavioral Pain Scale) | Pain (intubated/sedated patients) | Scores facial expression, upper limb movement, ventilator compliance (3–12). > 5 = significant pain. |
| CPOT (Critical-Care Pain Observation Tool) | Pain (non-verbal ICU patients) | 4 domains: facial expression, body movements, muscle tension, ventilator compliance or vocalization. Score 0–8. |
| ESAS (Edmonton Symptom Assessment Scale) | Global symptom burden | 9 symptoms rated 0–10: pain, fatigue, nausea, depression, anxiety, drowsiness, appetite, dyspnea, wellbeing. Quick, validated, tracks trends over time. |
| CAM (Confusion Assessment Method) | Delirium screening | 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.
- Allergies/intolerances: NSAID allergy → acetaminophen safe. True aspirin allergy (angioedema/anaphylaxis) → avoid all NSAIDs. Ondansetron → try prochlorperazine.
Reversible Causes to Rule Out
- Nausea: bowel obstruction (KUB/CT), medication side effect (review med list), hypercalcemia (check calcium), increased ICP (neuro exam + imaging), gastroparesis (DM history)
- Constipation: opioid-induced (most common inpatient cause), bowel obstruction (imaging), hypothyroidism (TSH), hypercalcemia, hypokalemia, medications (anticholinergics, calcium channel blockers)
- Dyspnea: pleural effusion (CXR → thoracentesis), PE (CT-PA), pneumonia, heart failure exacerbation, anxiety/panic, metabolic acidosis (compensatory hyperventilation)
- Pruritus: cholestatic liver disease (LFTs, bilirubin), uremia (BUN/Cr), drug reaction (timeline with new medications), contact dermatitis (exam)
- Insomnia: uncontrolled pain, delirium (CAM), medication effect (steroids, beta-agonists), sleep apnea, hospital environment
🚨 Management
Pain — Modified WHO Ladder (Non-Opioid Focus)
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.
Nausea / Vomiting — Mechanism-Based Approach
| Mechanism | Common Causes | Preferred Antiemetic |
|---|---|---|
| Serotonin (5-HT3) | Chemotherapy, post-operative, radiation | Ondansetron (Zofran) 4mg IV/PO q6h |
| Dopamine (D2) | Gastroparesis, medications, uremia | Metoclopramide (Reglan) 10mg IV/PO q6h (prokinetic), Prochlorperazine (Compazine) 10mg IV/PO q6h |
| Vestibular / Motion | Vertigo, inner ear, opioid-induced | Scopolamine patch 1.5mg q72h (transdermal), Meclizine 25mg q6h |
| Increased ICP / Obstruction | Brain metastases, bowel obstruction | 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). |
| Cholestatic (obstructive jaundice, PBC, drug-induced) | 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 — Persistent (> 48h) Management
- Non-pharmacologic first: vagal maneuvers (Valsalva, cold water gargle, biting a lemon), nasopharyngeal stimulation (catheter tip in posterior pharynx), rebreathing into paper bag
- First-line: Chlorpromazine (Thorazine) 25–50mg PO TID or 25mg IV (only FDA-approved drug for hiccups). Monitor for hypotension, QTc prolongation.
- Second-line: Baclofen (Lioresal) 5–10mg PO TID. GABA-B agonist. Particularly effective for hiccups of central origin.
- Third-line: Gabapentin (Neurontin) 300mg PO TID. Also useful when hiccups coexist with neuropathic pain or pruritus.
- Refractory: consider phrenic nerve block (IR guided), acupuncture (evidence growing), or metoclopramide 10mg if GI-related trigger.
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 | More predictable absorption than gabapentin. 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. |
| Trazodone (Desyrel) | SARI antidepressant | 25–50mg QHS | PO | 100mg (for insomnia) | Low delirium risk. Minimal anticholinergic burden. Rare: priapism. Safe in CKD. |
| Hydroxyzine (Vistaril) | Antihistamine (H1) | 25mg q6h | PO/IM | 100mg | First-line for histamine-mediated pruritus. Moderate anticholinergic — use cautiously in elderly. Also has anxiolytic properties. |
High-Risk Drug Interactions
- NSAIDs + anticoagulants — 3–6x increased GI bleeding risk. If must use, add PPI and limit to 3–5 days.
- Ondansetron + QTc-prolonging drugs (haloperidol, fluoroquinolones, methadone) — check baseline ECG. Avoid if QTc > 500ms.
- Metoclopramide + antipsychotics — both are dopamine antagonists. Additive EPS/tardive dyskinesia risk.
- Gabapentin + opioids — synergistic respiratory depression. FDA warning. Start gabapentin low and titrate slowly if on opioids.
- Stacking anticholinergics (hydroxyzine + diphenhydramine + promethazine + scopolamine) — delirium, urinary retention, ileus. Calculate anticholinergic burden score.
- 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. |
| Magic Mouthwash (compound) | 15 mL swish & spit q4–6h | Typical formulation: lidocaine 2% + diphenhydramine + antacid (Maalox) ± nystatin. Swish 1–2 min, spit. | 4–6 doses/24h | 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.
Key considerations: Elderly + CKD → NSAIDs contraindicated. Opioids risky → delirium, respiratory depression, falls. Need multimodal non-opioid approach.
Management:
- 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)
- Ensure pain is controlled (uncontrolled pain → poor sleep → delirium)
- 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.
- Delirium screen (CAM)? → Sleep deprivation + uncontrolled pain + anticholinergics = delirium triad. Address all three.
- Anticholinergic burden? → Count anticholinergic meds (hydroxyzine, diphenhydramine, promethazine, scopolamine). Minimize stacking.
- 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
Pain Ladder
Scheduled acetaminophen (foundation) → add NSAID/ketorolac → add gabapentinoid/lidocaine patch → nerve block. Reserve opioids for breakthrough only.
Nausea
Match to mechanism: ondansetron (5-HT3), metoclopramide (D2/prokinetic), scopolamine (vestibular), dexamethasone (ICP/obstruction). Layer pathways if refractory.
Dyspnea
Fan to face first (trigeminal V2 pathway). O2 only if SpO2 < 90%. Positioning. Low-dose morphine for refractory air hunger (one opioid exception).
Constipation
PEG 3350 (osmotic, first-line) + senna (stimulant). Docusate is no better than placebo — removed from guidelines (AGA-ACG 2023). Methylnaltrexone for opioid-induced. Rule out obstruction first.
Insomnia
Sleep hygiene + melatonin 3–5mg QHS. Trazodone 25–50mg if needed. Never benzos or zolpidem in hospitalized patients — delirium risk.
Pruritus
Histamine → hydroxyzine. Cholestatic → cholestyramine/rifampin. Uremic → gabapentin. Opioid-induced → rotate opioid or nalbuphine.
Hiccups
Chlorpromazine (only FDA-approved). Baclofen or gabapentin as alternatives. Vagal maneuvers first for acute episodes.
Core Principle
Multimodal: combine agents with different mechanisms at lower doses. Anticipate symptoms. Schedule, don't PRN. De-escalate daily. Non-pharm always.
📄 One Pager
Palliative Care · One Pager
Non-Opioid Symptom Management
Multimodal strategies for pain, nausea, dyspnea, constipation, insomnia, pruritus, and hiccups. Layer by mechanism. Schedule, don't PRN. Anticipate before symptoms escalate.
💊 Pain — Non-Opioid Ladder
- Step 1: Acetaminophen 1g q6h SCHEDULED (reduces opioid use 30%)
- Step 2: Add NSAID (ibuprofen 400mg q6h or ketorolac 15–30mg IV, max 5 days)
- Step 3: Add gabapentin (neuropathic), lidocaine 5% patch (localized), cyclobenzaprine (spasm)
- Avoid NSAIDs if: eGFR < 30, GI bleed hx, CHF, cirrhosis, on anticoagulants
🤮 Nausea — Match to Mechanism
- Chemo/post-op → ondansetron 4mg q6h (5-HT3)
- Gastroparesis → metoclopramide 10mg q6h (prokinetic, max 12 wks)
- Vestibular → scopolamine patch q72h
- Obstruction/ICP → dexamethasone 4–8mg IV daily
- Refractory → layer from different receptor classes
💨 Dyspnea + Constipation + Sleep
- Dyspnea: Fan to face (trigeminal V2). O2 only if SpO2 < 90%. Morphine 2mg IV for air hunger.
- Constipation: PEG 3350 17g daily + senna 2 tabs BID. Docusate is no better than placebo (AGA-ACG 2023) — do not use.
- Insomnia: Melatonin 3–5mg QHS → trazodone 25mg. NEVER benzos/zolpidem in hospital.
🔬 Pruritus + Hiccups
- Histamine itch: hydroxyzine 25mg q6h
- Cholestatic: cholestyramine 4g BID, rifampin, naltrexone
- Uremic: gabapentin 100mg post-dialysis
- Hiccups: chlorpromazine 25–50mg (FDA-approved), baclofen 5–10mg TID, gabapentin 300mg TID
⚠️ 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?
RoundsRx · Palliative Care · One Pager
WHO Pain Ladder · PRECISION 2016 · Beers Criteria 2023 · Abernethy 2010
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.
🔍 Overview
Risk Assessment
| Tool | Population | Threshold |
|---|---|---|
| Padua Score | Medical inpatients | ≥ 4 = high risk → pharmacologic prophylaxis |
| Caprini Score | Surgical patients | Score-based: 0 = early ambulation, 1–2 = SCDs, 3–4 = pharmacologic, ≥ 5 = extended prophylaxis |
| IMPROVE Bleed Score | Medical inpatients | Assesses bleeding risk -high score → mechanical prophylaxis instead |
Padua Score Components
- Active cancer (+3)
- Previous VTE (+3)
- Reduced mobility (+3)
- Known thrombophilia (+3)
- Recent trauma/surgery (+2)
- Age ≥ 70 (+1)
- Heart or respiratory failure (+1)
- AMI or stroke (+1)
- Acute infection or rheumatic disorder (+1)
- Obesity BMI ≥ 30 (+1)
- Hormonal therapy (+1)
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.
Special Populations
| Population | Recommendation | Notes |
|---|---|---|
| Pregnancy | Enoxaparin preferred; avoid warfarin | Increased VTE risk in pregnancy + postpartum. Warfarin is teratogenic (crosses placenta). |
| Cancer patients | LMWH superior to UFH | Consider extended prophylaxis post-discharge (COMPASS-CAT score for risk stratification). |
| Orthopedic surgery (hip/knee) | Extended prophylaxis × 35 days post-op | LMWH, rivaroxaban, or apixaban all acceptable. Standard 10–14 days is insufficient. |
| Morbid obesity (BMI >40) | Standard enoxaparin 40 mg may be subtherapeutic | Consider enoxaparin 40 mg q12h or UFH 7,500 units q8h for adequate prophylaxis. |
| CKD (CrCl <30) | Use UFH instead of LMWH | LMWH is renally cleared and accumulates → increased bleeding risk. |
| HIT history | Mechanical only or fondaparinux | NO heparin products (UFH or LMWH). Fondaparinux does not cross-react with HIT antibodies. |
| ICU patients | Pharmacologic + mechanical | Highest risk population — combination prophylaxis recommended. |
Mnemonic for VTE Risk Factors — "THROMBOSIS":
Travel / Thrombophilia · Hypercoagulable / HRT · Recent surgery · Obesity / Oral contraceptives · Malignancy · Bed rest / immobility · Obstetric (pregnancy) · Smoking · Injury / Inflammation · Sickle cell / SLE
Travel / Thrombophilia · Hypercoagulable / HRT · Recent surgery · Obesity / Oral contraceptives · Malignancy · Bed rest / immobility · Obstetric (pregnancy) · Smoking · Injury / Inflammation · Sickle cell / SLE
Clinical Examples
📋 Case 1 — Medical Patient VTE Prophylaxis
Patient: 72M admitted for pneumonia, BMI 25, no active bleeding.
Risk assessment (Padua Score):
- Acute infection (+1)
- Age ≥ 70 (+1)
- Reduced mobility (+3)
- Total = 5 → High risk
IMPROVE Bleed Score: Low → pharmacologic prophylaxis appropriate.
Order: Enoxaparin 40 mg SC daily + SCDs.
Key lesson: Most medical inpatients with acute illness + reduced mobility will score ≥ 4 on Padua. Always calculate, always prophylax.
📋 Case 2 — Extended Prophylaxis Post-Hip Replacement
Patient: 55F post-hip replacement, no active bleeding risk.
Risk assessment: Caprini ≥ 5 (major orthopedic surgery).
Order:
- Inpatient: Enoxaparin 40 mg SC daily starting 12h post-op.
- 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).
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.
⚡ Summary
Every Patient
VTE risk assessment on admission. Padua ≥ 4 (medical) or Caprini-based (surgical) → prophylax.
First-Line
Enoxaparin 40mg SC daily. Use UFH 5000 SC q8h if CrCl < 30 or high bleed risk.
Mechanical
SCDs if pharmacologic contraindicated (active bleed, plt < 50K, HIT, recent ICH).
Contraindications
Active bleeding, plt < 50K, recent ICH, epidural, HIT.
Obese Patients
Standard enox 40mg may be insufficient. Consider 40mg q12h or UFH q8h for BMI > 40.
Discharge
Assess need for extended prophylaxis (post-hip/knee surgery, high-risk medical → rivaroxaban).
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.
🔍 Overview
Classification
| Type | Key Features | HLA Association | Extra-articular Manifestations |
|---|---|---|---|
| Ankylosing Spondylitis | Inflammatory back pain, sacroiliitis, progressive spinal fusion ("bamboo spine"), kyphosis, enthesitis | HLA-B27 (~90%) | Anterior uveitis (#1 EAM), aortic insufficiency, apical pulmonary fibrosis, IgA nephropathy, cauda equina syndrome |
| Psoriatic Arthritis | Asymmetric oligoarthritis, DIP joints, dactylitis ("sausage digits"), enthesitis, arthritis mutilans, "pencil-in-cup" deformity | HLA-B27 (~50%), HLA-Cw6 (psoriasis) | Psoriatic skin plaques, nail pitting/onycholysis, uveitis, aortitis |
| Reactive Arthritis | Asymmetric oligoarthritis (large joints, lower extremity), post-infectious onset 1–4 weeks after GI/GU infection | HLA-B27 (~70%) | Conjunctivitis/uveitis, urethritis/cervicitis, keratoderma blennorrhagica, circinate balanitis, oral ulcers |
| IBD-Associated Arthritis | Peripheral (follows IBD activity, asymmetric, large joints) or axial (independent of IBD activity, sacroiliitis) | HLA-B27 (~50% axial, ~10% peripheral) | Erythema nodosum, pyoderma gangrenosum, uveitis, primary sclerosing cholangitis (UC) |
| Undifferentiated SpA | Features of SpA not meeting criteria for any specific subtype; inflammatory back pain, enthesitis, dactylitis | HLA-B27 (~70%) | Uveitis, psoriasiform rash. May evolve into AS or PsA over time. |
Reactive Arthritis Triad: "Can't see, Can't pee, Can't climb a tree" — Conjunctivitis (or uveitis), urethritis (or cervicitis), arthritis (asymmetric oligoarthritis, lower extremities). Triggered by GI infection (Salmonella, Shigella, Campylobacter, Yersinia) or GU infection (Chlamydia trachomatis).
SPINE Mnemonic — Ankylosing Spondylitis Features:
- Sacroiliitis — bilateral, symmetric; earliest and most characteristic finding on imaging
- Psoriasis association — overlap with PsA; up to 10% of AS patients develop psoriasis
- Inflammatory back pain — morning stiffness >30 minutes, improves with exercise, worse at rest, onset <40 years
- NSAIDs first-line — full-dose continuous NSAIDs (indomethacin, naproxen); try at least 2 NSAIDs before escalating
- Extra-articular — anterior uveitis (most common), aortitis/aortic insufficiency, interstitial lung disease (apical fibrosis), IgA nephropathy
Shared Features (All SpA)
- HLA-B27 positive (AS ~90%, reactive ~70%, PsA ~50%)
- Seronegative -RF negative, anti-CCP negative
- Enthesitis -inflammation at tendon/ligament insertion sites (Achilles, plantar fascia)
- Dactylitis -"sausage digit" diffuse swelling of entire finger/toe
- Inflammatory back pain -onset < 40, insidious, morning stiffness > 30 min, improves with exercise, worse at rest
- Extra-articular: uveitis, psoriasis, IBD
🚨 Management
Treatment Approach
| Line | Axial Disease | Peripheral Disease |
|---|---|---|
| 1st | NSAIDs (full dose, continuous if needed) | NSAIDs, local steroids |
| 2nd | Anti-TNF (Adalimumab (Humira), Etanercept (Enbrel), Infliximab (Remicade)) | DMARDs (Methotrexate (Trexall), Sulfasalazine (Azulfidine)) |
| 3rd | Secukinumab (Cosentyx) (anti-IL-17) | Anti-TNF or anti-IL-17 |
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).
Treatment Algorithm
| Step | Therapy | Agents | Notes |
|---|---|---|---|
| Step 1 | NSAIDs | Indomethacin (Indocin) 25–50 mg TID, Naproxen (Aleve) 500 mg BID | First-line for all SpA. Try ≥2 different NSAIDs (each for 2–4 weeks at full dose) before escalating. Continuous use for axial disease. |
| Step 2 | TNF Inhibitors | Adalimumab (Humira) 40 mg SC q2wk, Etanercept (Enbrel) 50 mg SC weekly, Infliximab (Remicade) 5 mg/kg IV q6–8wk | First-line biologic for axial SpA failing NSAIDs. Screen for TB/Hep B before starting. Monitor for infections. |
| Step 3 | IL-17 Inhibitors | Secukinumab (Cosentyx) 150 mg SC monthly, Ixekizumab (Taltz) 80 mg SC q4wk | Alternative to anti-TNF or after anti-TNF failure. Contraindicated in IBD-associated SpA (can trigger/worsen IBD). |
| PsA Special | DMARDs + PDE4i | Methotrexate (Trexall) 15–25 mg weekly, Apremilast (Otezla) 30 mg BID | 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
- Nail pitting: Multiple nails with onycholysis
- Psoriatic plaques: Elbows, scalp, intergluteal cleft
- RF, anti-CCP: Negative
Management:
- 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.
Classic triad present:
- Can't see: Bilateral conjunctivitis (painless, non-purulent)
- Can't pee: Sterile urethritis (urinalysis: pyuria, negative culture)
- Can't climb a tree: Asymmetric oligoarthritis (right knee effusion, left ankle pain)
- Additional: Keratoderma blennorrhagica (soles), circinate balanitis
Management:
- 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.
- CRP, ESR -may be elevated
- RF, anti-CCP -negative (to confirm seronegative)
- X-ray spine -syndesmophytes, bamboo spine (late AS)
- Skin exam -psoriasis (nails, scalp, intergluteal fold)
💊 Medications
| Drug | Dose | Indication |
|---|---|---|
| Naproxen (Aleve) | 500 mg BID | 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
Shared Features
RF-negative, HLA-B27+, enthesitis, dactylitis, inflammatory back pain, uveitis.
AS
Bamboo spine, sacroiliitis, uveitis, aortic insufficiency. MRI SI joints for early diagnosis.
PsA
DIP joints, nail pitting, dactylitis, pencil-in-cup deformity. Treat with DMARDs → biologics.
Reactive
"Can't see, pee, climb a tree." Post-GI/GU infection. Chlamydia testing important.
Axial Rx
NSAIDs → anti-TNF or anti-IL-17 directly. DMARDs DO NOT WORK for axial disease.
Inflammatory Back Pain
Age <40, insidious, AM stiffness >30min, better with exercise, worse with rest.
Essential Skills
🎓 Intern Survival Guide
Everything you wish someone told you on day one. Practical tips for presentations, notes, pages, and cross-cover from residents who've been there.
🗣️
How to Present on Rounds
The One-Liner: "Mr. Smith is a 62-year-old with CHF who presented with acute dyspnea."
Template:
1. One-liner (age, history, presentation)
2. Overnight events
3. Subjective (how patient feels today)
4. Vitals (trend, current)
5. Physical exam (pertinent positives/negatives)
6. Labs/studies (new results)
7. Assessment & Plan (by problem)
Pro tips: Under 3 minutes. Know your patient's hospital day. Have the med list ready. Lead with what changed.
Template:
1. One-liner (age, history, presentation)
2. Overnight events
3. Subjective (how patient feels today)
4. Vitals (trend, current)
5. Physical exam (pertinent positives/negatives)
6. Labs/studies (new results)
7. Assessment & Plan (by problem)
Pro tips: Under 3 minutes. Know your patient's hospital day. Have the med list ready. Lead with what changed.
📝
How to Write Notes
Admission H&P:
CC → HPI → ROS → PMH/PSH/Meds/Allergies/Social/Family → PE → Labs → A&P
Daily Progress Note:
Subjective → Objective (vitals, exam, labs) → Assessment & Plan (by problem)
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
CC → HPI → ROS → PMH/PSH/Meds/Allergies/Social/Family → PE → Labs → A&P
Daily Progress Note:
Subjective → Objective (vitals, exam, labs) → Assessment & Plan (by problem)
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
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
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
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
• 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
Indications
• Vasopressor administration (norepinephrine, vasopressin)
• Inadequate peripheral access
• CVP monitoring
• TPN / hyperosmolar infusions (> 900 mOsm)
• Hemodialysis access
• Rapid volume resuscitation (large-bore catheter)
• Inadequate peripheral access
• CVP monitoring
• TPN / hyperosmolar infusions (> 900 mOsm)
• Hemodialysis access
• Rapid volume resuscitation (large-bore catheter)
Contraindications
• 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
• 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
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)
• 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
• 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
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
Indications
• Suspected meningitis/encephalitis
• Rule out SAH (CT-negative thunderclap headache)
• Diagnosis: MS, GBS, carcinomatous meningitis, normal pressure hydrocephalus
• Therapeutic: idiopathic intracranial hypertension (IIH), intrathecal medications
• Rule out SAH (CT-negative thunderclap headache)
• Diagnosis: MS, GBS, carcinomatous meningitis, normal pressure hydrocephalus
• Therapeutic: idiopathic intracranial hypertension (IIH), intrathecal medications
Contraindications
• ↑ 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
• 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
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)
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
• 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
• 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)
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
• 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
Transudate: CHF, cirrhosis, nephrotic syndrome
Exudate: Infection (parapneumonic/empyema), malignancy, PE, TB, rheumatologic
• Pleural LDH / serum LDH > 0.6
• Pleural LDH > 2/3 upper limit of normal serum LDH
Transudate: CHF, cirrhosis, nephrotic syndrome
Exudate: Infection (parapneumonic/empyema), malignancy, PE, TB, rheumatologic
Technique
1. Position: Seated, leaning forward on bedside table
2. US guidance mandatory -mark fluid pocket, ensure ≥ 1 cm depth
3. Site: 1-2 interspaces below fluid level, posterior axillary or midscapular line. Always go ABOVE the rib (neurovascular bundle runs under each rib)
4. Prep: Chlorhexidine, sterile drape
5. Lidocaine: Subcutaneous → intercostal muscles → OVER the rib → parietal pleura (aspirate as you go -fluid confirms pleural space)
6. Insert catheter-over-needle -advance while aspirating, then thread catheter
7. Collect samples: Cell count, protein, LDH, glucose, pH, culture, cytology
8. Max removal: 1-1.5L per session (prevents re-expansion pulmonary edema). Stop if chest tightness or cough.
9. Post-procedure CXR -only if air aspirated, symptoms, or multiple needle passes
2. US guidance mandatory -mark fluid pocket, ensure ≥ 1 cm depth
3. Site: 1-2 interspaces below fluid level, posterior axillary or midscapular line. Always go ABOVE the rib (neurovascular bundle runs under each rib)
4. Prep: Chlorhexidine, sterile drape
5. Lidocaine: Subcutaneous → intercostal muscles → OVER the rib → parietal pleura (aspirate as you go -fluid confirms pleural space)
6. Insert catheter-over-needle -advance while aspirating, then thread catheter
7. Collect samples: Cell count, protein, LDH, glucose, pH, culture, cytology
8. Max removal: 1-1.5L per session (prevents re-expansion pulmonary edema). Stop if chest tightness or cough.
9. Post-procedure CXR -only if air aspirated, symptoms, or multiple needle passes
⚠️ Complications
Pneumothorax (US guidance reduces risk dramatically), bleeding, re-expansion pulmonary edema (remove ≤ 1.5L), vasovagal, infection. Empyema (pH < 7.2, glucose < 40, pus) → chest tube, NOT repeat thoracentesis.
🟣
Rapid Sequence Intubation (RSI)
Emergent airway management -preparation, pre-oxygenation, induction, paralysis, placement
Indications for Intubation
• Failure to protect airway (GCS ≤ 8)
• Failure to oxygenate (refractory hypoxemia despite NRB/NIPPV)
• Failure to ventilate (rising PaCO₂, respiratory fatigue)
• Anticipated clinical course (burns, angioedema, massive hematemesis)
• Failure to oxygenate (refractory hypoxemia despite NRB/NIPPV)
• Failure to ventilate (rising PaCO₂, respiratory fatigue)
• Anticipated clinical course (burns, angioedema, massive hematemesis)
The 7 P's of RSI
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
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
• 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
⚡ Electrolyte Replacement
Standard replacement protocols for common electrolyte abnormalities. Adjust for renal function. Recheck levels after repletion.
🟠 Potassium (K⁺)
Goal: 4.0–5.0 mEq/L (≥ 4.0 in cardiac patients)
| K⁺ Level | Replacement | Expected ↑ |
|---|---|---|
| 3.5–3.9 | KCl 40 mEq PO × 1 | ↑ ~0.4 mEq/L |
| 3.0–3.4 | KCl 40 mEq PO × 2 (or 20 mEq IV × 2) | ↑ ~0.8 mEq/L |
| 2.5–2.9 | KCl 20 mEq IV × 3–4 + 40 mEq PO | Variable |
| < 2.5 | KCl 40 mEq IV (10 mEq/hr peripheral, 20 mEq/hr central) + telemetry | Check q2h |
⚠️ Always check Mg²⁺. Hypomagnesemia prevents K⁺ correction. Fix Mg first. Max peripheral IV rate: 10 mEq/hr (burning). Max central: 20 mEq/hr. Telemetry if K⁺ < 3.0.
🟡 Magnesium (Mg²⁺)
Goal: ≥ 2.0 mg/dL (≥ 2.0 in cardiac/ICU)
| Mg²⁺ Level | Replacement |
|---|---|
| 1.5–1.9 | MgO 400 mg PO BID × 2 days (or MgSO₄ 2g IV × 1) |
| 1.0–1.4 | MgSO₄ 2g IV × 2 doses |
| < 1.0 | MgSO₄ 4g IV over 4h + recheck. Telemetry. May need 8–12g total over 24h. |
⚠️ Key facts: IV Mg causes flushing/warmth (warn patient). Oral Mg causes diarrhea (MgO worst, Mg glycinate better tolerated). Renal patients: reduce dose -Mg is renally cleared. 50% of hypoK is from concurrent hypoMg.
🟢 Phosphate (PO₄)
Goal: 2.5–4.5 mg/dL
| PO₄ Level | Replacement |
|---|---|
| 2.0–2.4 | Neutra-Phos 2 packets PO (or K-Phos 2 tabs PO) |
| 1.5–1.9 | Na-Phos or K-Phos 15 mmol IV over 2h |
| < 1.5 | Na-Phos or K-Phos 30 mmol IV over 4–6h (max 7 mmol/hr) |
⚠️ Choose Na-Phos vs K-Phos based on K⁺ level. K-Phos if K is also low (repletes both). Na-Phos if K is normal/high. IV phosphate can cause hypocalcemia -check Ca. Reduce dose in renal failure.
🔵 Calcium (Ca²⁺)
Goal: iCa 1.1–1.3 mmol/L / Total Ca 8.5–10.5 mg/dL (corrected for albumin)
| Scenario | Replacement |
|---|---|
| Mild (asymptomatic) | Calcium carbonate (Tums) 1–2g PO TID with meals + Vitamin D |
| Moderate (symptomatic) | Calcium gluconate 1–2g IV over 10–20 min |
| Severe / symptomatic | Calcium gluconate 1–2g IV bolus → continuous infusion 0.5–1.5 mg/kg/hr |
| Cardiac arrest / severe | Calcium CHLORIDE 1g IV push (central line only -3× more elemental Ca) |
⚠️ Always check Mg first. HypoMg → impaired PTH → refractory hypoCa. Correct albumin: add 0.8 per 1g albumin below 4.0. CaCl via central line ONLY (tissue necrosis if infiltrates). Ca gluconate safe peripherally.
🔴 Sodium (Na⁺) -Correction Limits
See Hyponatremia topic for full management
≤ 8
mEq/L rise in 24h
(max safe correction rate)
(max safe correction rate)
≤ 10–12
mEq/L rise in 48h
(be even more cautious if chronic)
(be even more cautious if chronic)
ODS
Osmotic demyelination syndrome
if corrected too fast
if corrected too fast
Hyponatremia: NS for hypovolemic, fluid restrict for euvolemic (SIADH), diuretics for hypervolemic. HTS 3% for severe symptoms (seizure, coma) -100 mL bolus, recheck Na in 2h. Hypernatremia: Free water deficit = 0.6 × wt × ((Na/140) − 1). Replace slowly -max correction 10 mEq/24h to avoid cerebral edema.
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 | When to Use |
|---|---|---|---|---|---|---|
| Normal Saline (0.9% NaCl) | 154 | 154 | 0 | None | 308 | 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 | Preferred resuscitation fluid. More physiologic. Less acidosis than NS. Contains 4 mEq/L K⁺ but this is clinically insignificant -LR actually lowers serum K⁺ better than NS because NS causes acidosis-driven K⁺ shift (SMART, 2018). Safe in hyperkalemia. |
| D5W (5% Dextrose) | 0 | 0 | 0 | None | 252 | Free water. Hypernatremia correction, medication diluent. NOT for resuscitation (distributes to total body water). |
| D5 1/2 NS | 77 | 77 | 0 | None | 406 | Maintenance fluid. Provides free water + some Na. Common maintenance choice. |
| D5 NS | 154 | 154 | 0 | None | 560 | Maintenance with higher Na. DKA (when glucose < 250, switch from NS to D5NS). |
| 3% Hypertonic Saline | 513 | 513 | 0 | None | 1026 | Severe symptomatic hyponatremia (seizure, coma). 100 mL bolus. Also for ↑ ICP in TBI. Often needs central line. |
| Albumin 5% | 145 | - | - | - | 290 | Volume expansion in cirrhosis (post-LVP, SBP). Sepsis (controversial). Oncotic pressure support. |
| Albumin 25% | 145 | - | - | - | 1500 | Concentrated -pulls fluid intravascularly. Diuretic-resistant edema with hypoalbuminemia. Give with furosemide (Lasix). |
📐 Maintenance Fluid Rate
4-2-1 Rule (Holliday-Segar):
• First 10 kg: 4 mL/kg/hr
• Next 10 kg: 2 mL/kg/hr
• Each kg above 20: 1 mL/kg/hr
Example (70 kg):
(10×4) + (10×2) + (50×1) = 40 + 20 + 50 = 110 mL/hr
Common shortcut: Most adults get 75–125 mL/hr maintenance. Adjust for heart failure (restrict), renal failure, and ongoing losses.
• First 10 kg: 4 mL/kg/hr
• Next 10 kg: 2 mL/kg/hr
• Each kg above 20: 1 mL/kg/hr
Example (70 kg):
(10×4) + (10×2) + (50×1) = 40 + 20 + 50 = 110 mL/hr
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 1/12 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.
• D5W for resuscitation → it's free water, not volume expander. Only 1/12 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.
| Product | Threshold | Expected Response | Key Notes |
|---|---|---|---|
| pRBCs | Hgb < 7 (general) Hgb < 8 (ACS, symptomatic cardiac) Hgb < 10 (some surgical/active bleed) | 1 unit ↑ Hgb ~1 g/dL | Restrictive (Hgb < 7) is preferred over liberal in most patients. TRICC, 1999; FOCUS, 2011 |
| Platelets | < 10K (prophylactic) < 20K (fever/infection) < 50K (active bleeding/procedure) < 100K (neurosurgery/CNS procedure) | 1 unit ↑ plt ~30–50K | Do NOT transfuse in TTP/HIT (worsens thrombosis). In ITP, only if active severe bleeding. |
| FFP | Active bleeding + INR > 1.5 Urgent warfarin reversal (with PCC) DIC with bleeding Massive transfusion (1:1:1) | ~10–15 mL/kg | NOT for correcting mildly elevated INR without bleeding. Liver disease INR is NOT an indication for FFP alone. |
| Cryoprecipitate | Fibrinogen < 150 (DIC) Fibrinogen < 200 (MTP) Uremic bleeding (contains vWF) | 10 units ↑ fibrinogen ~70 mg/dL | Contains: fibrinogen, factor VIII, vWF, factor XIII. Use for fibrinogen replacement primarily. |
🚨 Transfusion Reactions
Febrile Non-Hemolytic (most common)
→ Fever, chills. Stop transfusion, acetaminophen (Tylenol). Rule out hemolytic.
Allergic (urticarial)
→ Hives, itching. Stop, diphenhydramine (Benadryl) 25-50mg IV. If mild and resolves, can restart slowly.
Anaphylaxis
→ Hypotension, bronchospasm, angioedema. STOP. Epinephrine (Adrenalin) 0.3mg IM. IgA deficiency is classic risk factor.
Acute Hemolytic (most dangerous)
→ ABO incompatibility. Fever, flank pain, dark urine, DIC. STOP IMMEDIATELY. NS bolus, send type & screen recollection. Can be fatal.
TRALI (Transfusion-Related Acute Lung Injury)
→ Acute respiratory distress within 6h. Bilateral infiltrates. No volume overload. Supportive care. #1 cause of transfusion-related death.
TACO (Transfusion-Associated Circulatory Overload)
→ Dyspnea, HTN, pulmonary edema. Volume overload. Diuretics. Transfuse slowly in CHF/elderly.
→ Fever, chills. Stop transfusion, acetaminophen (Tylenol). Rule out hemolytic.
Allergic (urticarial)
→ Hives, itching. Stop, diphenhydramine (Benadryl) 25-50mg IV. If mild and resolves, can restart slowly.
Anaphylaxis
→ Hypotension, bronchospasm, angioedema. STOP. Epinephrine (Adrenalin) 0.3mg IM. IgA deficiency is classic risk factor.
Acute Hemolytic (most dangerous)
→ ABO incompatibility. Fever, flank pain, dark urine, DIC. STOP IMMEDIATELY. NS bolus, send type & screen recollection. Can be fatal.
TRALI (Transfusion-Related Acute Lung Injury)
→ Acute respiratory distress within 6h. Bilateral infiltrates. No volume overload. Supportive care. #1 cause of transfusion-related death.
TACO (Transfusion-Associated Circulatory Overload)
→ Dyspnea, HTN, pulmonary edema. Volume overload. Diuretics. Transfuse slowly in CHF/elderly.
📋 Practical Tips
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
• 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
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
Localisation:
• II, III, aVF → Inferior (RCA)
• V1-V4 → Anterior (LAD)
• I, aVL, V5-V6 → Lateral (LCx)
• V1-V2 depression → Posterior (get V7-V9)
• V3R-V4R elevation → RV infarct (avoid nitrates/volume depletion)
Action: Activate cath lab. ASA 325mg chewed. Heparin. Door-to-balloon < 90 min.
Morphology: Concave-up ("tombstone") or convex-up ST elevation with reciprocal ST depression in opposite leads
Localisation:
• II, III, aVF → Inferior (RCA)
• V1-V4 → Anterior (LAD)
• I, aVL, V5-V6 → Lateral (LCx)
• V1-V2 depression → Posterior (get V7-V9)
• V3R-V4R elevation → RV infarct (avoid nitrates/volume depletion)
Action: Activate cath lab. ASA 325mg chewed. Heparin. Door-to-balloon < 90 min.
Ventricular Tachycardia (VT)
Wide complex, regular, ≥ 3 consecutive beats
Pattern: Wide QRS (> 120ms), regular, rate 150-250 bpm
Features favouring VT over SVT with aberrancy:
• AV dissociation (P waves marching independently)
• Capture/fusion beats
• Concordance (all precordial QRS same direction)
• Very wide QRS (> 160ms)
• Northwest axis (extreme right axis deviation)
Rule: Wide complex tachycardia = VT until proven otherwise, especially if age > 50 or structural heart disease.
Action: Stable → amiodarone (Cordarone) 150mg IV. Unstable → synchronized cardioversion. Pulseless → defibrillate.
Features favouring VT over SVT with aberrancy:
• AV dissociation (P waves marching independently)
• Capture/fusion beats
• Concordance (all precordial QRS same direction)
• Very wide QRS (> 160ms)
• Northwest axis (extreme right axis deviation)
Rule: Wide complex tachycardia = VT until proven otherwise, especially if age > 50 or structural heart disease.
Action: Stable → amiodarone (Cordarone) 150mg IV. Unstable → synchronized cardioversion. Pulseless → defibrillate.
Hyperkalemia
Progressive changes as K⁺ rises
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 (stabilises membrane). Then insulin + D50 to shift K⁺. See Hyperkalemia topic for full protocol.
• 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 (stabilises 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.
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.
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.
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)
Common offenders: Haloperidol (Haldol), ondansetron (Zofran), fluoroquinolones, azithromycin (Zithromax), methadone, amiodarone (Cordarone), antipsychotics, hypoK, hypoMg
Action: Stop offending drug. Replete K⁺ > 4.0, Mg²⁺ > 2.0. If TdP occurs: IV magnesium 2g bolus + overdrive pacing (↑ HR shortens QT).
Concerning: > 480ms
Dangerous: > 500ms → high risk for Torsades de Pointes (TdP)
Common offenders: Haloperidol (Haldol), ondansetron (Zofran), fluoroquinolones, azithromycin (Zithromax), methadone, amiodarone (Cordarone), antipsychotics, hypoK, hypoMg
Action: Stop offending drug. Replete K⁺ > 4.0, Mg²⁺ > 2.0. If TdP occurs: IV magnesium 2g bolus + overdrive pacing (↑ HR shortens QT).
PE / Right Heart Strain
Acute right ventricular pressure overload
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.
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 Recognise
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.
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: localised (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!).
Distinguish from STEMI:
• Pericarditis: diffuse (many territories), NO reciprocal changes, PR depression, concave-up
• STEMI: localised (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.
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.
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 haemodynamically unstable, life-threatening arrhythmia, or K⁺ > 5.0.
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 haemodynamically 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.
Other findings: Bradycardia, prolonged intervals (PR, QRS, QT), atrial fibrillation, muscle tremor artifact (shivering)
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."
Other findings: Bradycardia, prolonged intervals (PR, QRS, QT), atrial fibrillation, muscle tremor artifact (shivering)
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.
1. CBC Abnormalities
| Lab | High | Low | Key Differentials |
|---|---|---|---|
| WBC | >11K: infection, steroids, stress, CML, leukemoid reaction | <4K: viral, meds (chemo, immunosuppressants), aplastic anemia, SLE, HIV | Bandemia >10% = left shift → suggests bacterial infection |
| Hemoglobin | >16.5 M / 15 F: polycythemia vera, chronic hypoxia, dehydration | See anemia workup below | MCV guides anemia workup |
| Platelets | >450K: reactive (infection/inflammation/iron deficiency), CML, ET | <150K: ITP*, TTP*/HUS*, DIC*, HIT*, liver disease, meds, pseudothrombocytopenia *ITP = Immune Thrombocytopenic Purpura *TTP = Thrombotic Thrombocytopenic Purpura *HUS = Hemolytic Uremic Syndrome *DIC = Disseminated Intravascular Coagulation *HIT = Heparin-Induced Thrombocytopenia | ALWAYS check smear if <50K. Rule out pseudothrombocytopenia (EDTA clumping) |
2. Anemia Workup (by MCV)
| MCV Category | Differential Diagnosis |
|---|---|
| Microcytic (<80) | Iron deficiency (most common), thalassemia, anemia of chronic disease, sideroblastic, lead poisoning |
| Normocytic (80–100) | Acute blood loss, ACD, CKD, mixed deficiency, bone marrow failure |
| Macrocytic (>100) | B12/folate deficiency, alcohol, liver disease, hypothyroidism, MDS, meds (methotrexate, AZT) |
Iron Studies Interpretation
| Condition | Ferritin | TIBC | Iron | % Sat |
|---|---|---|---|---|
| Iron deficiency | ↓ (<30) | ↑ | ↓ | ↓ (<20%) |
| ACD | ↑ or normal | ↓ | ↓ | Normal or ↓ |
| Thalassemia | Normal | Normal | Normal | Normal |
| Sideroblastic | ↑ | Normal | ↑ | ↑ |
3. Hemolysis Workup
| Finding | Expected in Hemolysis |
|---|---|
| LDH | ↑↑ (released from lysed RBCs) |
| Haptoglobin | ↓↓ (binds free hemoglobin → consumed) |
| Indirect bilirubin | ↑ (from heme breakdown) |
| Reticulocyte count | ↑ (bone marrow compensating) |
| Peripheral smear | Schistocytes (MAHA*), spherocytes (autoimmune), sickle cells *MAHA = Microangiopathic Hemolytic Anemia |
| Direct Coombs (DAT) | + = autoimmune hemolysis, − = non-immune (TTP, DIC, mechanical) |
4. Liver Panel
| Pattern | AST/ALT | Alk Phos | Bilirubin | Interpretation |
|---|---|---|---|---|
| Hepatocellular | ↑↑↑ (>1000) | Normal / mild ↑ | Variable | Viral hepatitis, acetaminophen, ischemic hepatitis, autoimmune |
| Cholestatic | Mild ↑ | ↑↑↑ | ↑ (conjugated) | Biliary obstruction, PBC, PSC, drugs |
| Infiltrative | Normal / mild ↑ | ↑↑ | Normal | Malignancy, granulomatous disease, amyloid |
| Mixed | ↑↑ | ↑↑ | ↑ | Drug-induced, sepsis |
Liver Panel Pearls: AST:ALT >2:1 = alcoholic liver disease (De Ritis ratio). ALT > AST in most other causes. AST/ALT >1000 = “shock liver,” acetaminophen, viral, Wilson’s, autoimmune.
5. Renal Panel
| Lab / Ratio | Significance |
|---|---|
| BUN/Cr ratio >20:1 | Pre-renal azotemia, GI bleed (protein load), high-protein diet |
| BUN/Cr ratio <10:1 | Intrinsic renal, liver disease, malnutrition |
| FENa* <1% *FENa = Fractional Excretion of Sodium | Pre-renal (kidneys retaining Na) |
| FENa >2% | Intrinsic renal (ATN* — kidneys can’t retain Na) *ATN = Acute Tubular Necrosis |
| FEUrea* <35% *FEUrea = Fractional Excretion of Urea | Pre-renal (use if on diuretics — FENa unreliable) |
| Urine Na <20 | Pre-renal |
| Urine Na >40 | Intrinsic renal or SIADH |
6. Coagulation
| Lab | Measures | Causes of Prolongation |
|---|---|---|
| PT/INR | Extrinsic pathway (VII) → common | Warfarin, liver disease, vitamin K deficiency, DIC |
| aPTT | Intrinsic pathway (XII, XI, IX, VIII) | Heparin, hemophilia A/B, lupus anticoagulant, DIC |
| Both ↑ | Common pathway (X, V, II, fibrinogen) | DIC, liver failure, massive transfusion |
| Mixing study corrects | Factor deficiency | Replace the missing factor |
| Mixing study doesn’t correct | Inhibitor present | Lupus anticoagulant, factor inhibitor |
DIC Labs: ↑PT, ↑aPTT, ↓fibrinogen (<200), ↑D-dimer, ↓platelets, schistocytes on smear.
7. Cardiac Biomarkers
| Marker | Elevated In | Interpretation Pearls |
|---|---|---|
| Troponin | MI, PE, myocarditis, HF, renal failure, sepsis, demand ischemia | Rise-fall pattern with delta = acute MI. Chronically elevated = CKD/HF |
| BNP / NT-proBNP | HF, cor pulmonale, PE, AF, sepsis | BNP >400 or NT-proBNP >900 strongly suggests HF. Age-adjusted cutoffs for NT-proBNP. Falsely LOW in obesity |
| CK / CK-MB | MI, rhabdomyolysis, myositis, strenuous exercise | Less specific than troponin for MI. CK >5× ULN in rhabdo |
8. Inflammatory Markers
| Marker | Key Points | High-Yield Values |
|---|---|---|
| ESR | Nonspecific. ↑ in infection, autoimmune, malignancy, anemia, pregnancy | Very high (>100): endocarditis, osteomyelitis, TB, myeloma, temporal arteritis |
| CRP | More specific than ESR. Rises/falls faster | ↑ in infection, inflammation. <10 = mild, >100 = likely bacterial infection |
| Procalcitonin | More specific for BACTERIAL infection | <0.25 = unlikely bacterial, >0.5 = likely bacterial. Guides antibiotic de-escalation. NOT elevated in viral or autoimmune |
| Ferritin | Acute phase reactant — ↑ in inflammation regardless of iron status | Very high (>1000): HLH, adult-onset Still’s, liver disease, iron overload |
| LDH | Nonspecific tissue damage marker | ↑ in hemolysis, lymphoma, liver disease, PE, PJP, TLS |
9. Thyroid Function Tests
| TSH | Free T4 | Diagnosis |
|---|---|---|
| ↑ | ↓ | Primary hypothyroidism |
| ↓ | ↑ | Primary hyperthyroidism (Graves’, toxic nodule, thyroiditis) |
| ↓ | ↓ | Central hypothyroidism (pituitary / hypothalamic) |
| ↓ | Normal | Subclinical hyperthyroidism or sick euthyroid |
| ↑ | Normal | Subclinical hypothyroidism |
10. ABG Interpretation (Step-by-Step)
| Step | Action |
|---|---|
| 1 | pH <7.35 = acidemia, pH >7.45 = alkalemia |
| 2 | 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.
YouTube Channels
| Channel | Focus | Why It's Good |
|---|---|---|
| OnlineMedEd | General IM | High-yield video lectures covering all core clerkship and residency topics |
| Conan Liu MD | General IM | Internal medicine & residency -practical clinical content for residents |
| The ICU Channel | Critical Care | Ventilator management, hemodynamics, and ICU procedures explained clearly |
| Ninja Nerd | Board Review | Detailed pathophysiology lectures with excellent whiteboard diagrams |
Podcasts
| Podcast | Focus | Why It's Good |
|---|---|---|
| The Curbsiders | General IM | Deep dives on clinical topics with expert guests. The go-to IM podcast |
| EMCrit | Critical Care | Scott Weingart -gold standard for resuscitation and ICU education |
| Core IM | General IM | 5-Pearls format -concise clinical pearls. Perfect for commutes |
| Clinical Problem Solvers | General IM | Clinical reasoning podcast -diagnostic thinking step by step |
| Divine Intervention | Board Review | High-yield board review for Step 2/Step 3. Rapid-fire clinical pearls |
🌐 Websites & Blogs
| Website | Focus | Why It's Good |
|---|---|---|
| Life in the Fast Lane (LITFL) | Emergency Med | Massive free library -ECG interpretation, toxicology, critical care |
| UpToDate | General IM | 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
📋 Clinical Guidelines
| Resource | What It Covers |
|---|---|
| Surviving Sepsis Campaign 2026 | Latest SSC guidelines -replaces qSOFA with NEWS/MEWS, updated fluid resuscitation, vasopressor, and corticosteroid recommendations |
| Surviving Sepsis Campaign 2021 | Prior SSC guidelines -sepsis bundles, 1-hour targets, and initial resuscitation framework |
| AHA/ACC Heart Failure Guidelines | 2022 HF guidelines including GDMT rapid initiation |
| KDIGO Guidelines | CKD, AKI, glomerulonephritis, and electrolyte management |
| IDSA Practice Guidelines | Infectious disease -CAP, HAP, C. diff, UTI, endocarditis, and more |
| ATS Guidelines | Pulmonary -COPD, asthma, ARDS, ILD, pulmonary hypertension |
| ADA Standards of Care | Diabetes management -inpatient, outpatient, DKA, insulin protocols |
🧰 Clinical Tools
| Tool | What It Does |
|---|---|
| MDCalc | Clinical calculators -MELD, Wells, CHA₂DS₂-VASc, CURB-65, and 500+ more |
| Epocrates | Drug reference -interactions, dosing, pill identification. Free version available |
| Micromedex | Comprehensive drug information -usually institutional access |
📚 Reference & Learning
| Resource | What It Is |
|---|---|
| UpToDate | The clinical decision support standard. Usually institutional access |
| PubMed | 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.
System
About RoundsRx
Free, evidence-based clinical toolkit -built by residents, for residents.
What is RoundsRx?
RoundsRx is a free clinical toolkit designed for the bedside. It covers 240 clinical topics and tools across 15 rotations -from ICU protocols and cardiology to nephrology, heme/onc, and palliative care. Every topic includes a standardized structure: overview, workup, management, medications, monitoring, rounds presentation, and a printable one-pager.
Unlike traditional references, RoundsRx is built around how residents actually work -with 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.
Latest Build
April 1, 2026
Version 4.1
Build Stats
240
Clinical Topics & Tools
5,300+
Drug Table Entries
962
Pimp Questions
15
Rotation Pages
961
Trial Citations
825
Clinical Alert Flags
23
Calculators
544
Clinical Scenarios
Key Features
🔍 Smart Search
Full-text search across every word on the site — all topics, drugs, and 1,120 trial citations. Results highlight and scroll directly to the matching content.
📚 Trial Citations
1,120 trial badges with hover tooltips explaining study design, key findings, and clinical impact.
🧠 Pimp Me Quiz
968 attending-style questions with reveal answers -including SSC 2026 guideline updates. Filter by rotation or topic. Perfect for pre-rounds prep.
🔄 Updated Practice
830 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.
🧮 25 Calculators
Organized by rotation -Nephrology, Cardiology, Pulmonology, ICU, GI, General. CrCl, MELD, CHA₂DS₂-VASc, Wells, NEWS/MEWS, and more.
🖨️ Print-Ready
Every topic has a one-pager designed for printing. QR poster for resident lounges. Optimized print styles.
Terms of Use
© 2026 RoundsRx. All rights reserved.
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
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
- Search highlight: clicking a result navigates to the exact text match with a purple pulse animation that auto-clears after 4 seconds
- Fixed 5 unbalanced views (COPD, Asthma, Massive Transfusion, Pancytopenia, Intra-abdominal Infection) and 1 nested view (Chemotherapy Toxicity was swallowed inside Pancytopenia)
- Fixed 8 unclosed carousels: content was trapped inside last carousel card in TTM, Tamponade, Pulmonary HTN, IBD, Cholangitis, Metabolic Alkalosis, ICH, and Acute Abdomen
- Dynamic rendering for SEO: edge function now strips non-target views for search crawlers so each URL serves unique HTML content — fixes Google "duplicate content" and "alternate page with canonical" indexing issues
- Unified topic count to 240 across all meta tags (og:description, twitter, Schema.org, manifest — were inconsistent at 175/232/239/241)
- Added 9 missing pages to sitemap (APS, CLABSI, HSV, Shingles, IAI, Syncope, Syphilis, VTE, Shift Tracker)
- Fixed manifest.webmanifest: split maskable icon entries per Google PWA guidelines
- Merged cellulitis monitoring into Rounds section, removed last stray monitoring tab
- Added inline hidden attribute + display:none to all non-active views to prevent content bleed-through during progressive rendering
- Service worker cache bumped to v4
- Corrected build stats: 962 pimp questions, 961 trial citations, 825 alert flags, 23 calculators, 544 clinical scenarios
v4.0 — March 31, 2026
- New topic: Syncope -full view with risk stratification (SFSR, CSRS, ROSE), workup algorithm, cardiac vs vasovagal management, 6 pimp questions, clinical examples, and one-pager
- New topic: VTE Prophylaxis & Treatment -full view with Padua score, Wells DVT/PE, PERC rule, age-adjusted D-dimer, acute treatment (DOACs, heparin, warfarin), thrombolysis criteria, and cancer/HIT/pregnancy special situations
- Fixed 22 structurally imbalanced views causing content bleed-through across pages (DKA content was leaking into Landmark Trials and other views)
- Fixed toxicology view: removed corrupted HTML fragment breaking tox-management section
- Fixed pancytopenia view: repaired malformed pancy-summary section tag, removed orphaned monitoring content from carousel
- Removed 40 orphan monitoring sections (514 lines) left over from monitoring merge
- Fixed 18 unclosed carousel divs causing content to render inside last carousel card
- 241 total views, 0 structural issues, 0 orphan tabs
v3.9 — March 31, 2026
- New ID topics: Herpes Simplex (HSV), Syphilis, Herpes Zoster (Shingles), Septic Arthritis, CLABSI & Line Infections, Intra-Abdominal Infections — full views with overview, workup, management, medications, rounds, summary, and one-pager
- Fixed Cellulitis topic: repaired truncated content, added severity classification table, IV→PO criteria, and recurrence prevention with PATCH I trial
- Landmark Trials Library: added detail summaries (N=, key facts, conclusion) to 150+ trial cards across all categories
- Removed P-values/HRs/CIs from 2025–2026 trial cards — replaced with concise clinical conclusions
- All trial card categories completed: Sepsis & Critical Care, ARDS & Ventilation, Airway & Sedation, Cardiology (ACS, HF, Shock, AF, HTN), Pulmonology, Post-Cardiac Arrest, Status Epilepticus, Neurology, GI & Hepatology, Diabetes & Endocrine, Nephrology, Rheumatology, Infectious Disease, COVID-19, Oncology, Hematology & Transfusion, IV Fluids & Resuscitation
v3.8 — March 30, 2026
- Fixed mnemonic formatting: bold first letters now display inline with words across all mnemonics (MUDPILES, HARDUPS, LEMON, CRAB, SNOOP, ABCDEF, CHA₂DS₂-VASc, 7 P's of RSI, HEPATICS, CREST, ABVD, and more)
- CSS fix: alert-box strong tags changed from display:block to display:inline — mnemonic letters no longer stack above words
- BiPAP settings guide and ventilator modes sections now collapsible to save vertical space
- NIV contraindications condensed from 7-line list to single-line alert
- Airway & Ventilator Management: updated meta title and description to reflect full topic scope
v3.7 — March 30, 2026
- Expanded 3 thin clinical topics: Non-Opioid Symptom Management, Diabetic Foot Infection, SVC Syndrome (60–100 lines → 450–580 lines each)
- SEO: JSON-LD MedicalWebPage structured data injected per topic via edge function
- SEO: aggressive CSS injection — Googlebot now sees only the target view per URL
- Sitemap: all lastmod dates updated, 2 orphaned URLs removed, 1 slug corrected
- Fixed 6 unbalanced views (AKI, Upper GI Bleed, Falls Risk, RA, Antibiotics, Pneumothorax)
- Resolved 13 duplicate section IDs across 5 views (hypercalcemia, necrotizing fasciitis, palliative extubation, acid-base disorders, toxicology overdose)
v3.6 — March 29, 2026
- 106 trial citations converted to styled spans with hover descriptions
- RCT Library renamed to Landmark Trials — reorganized by topic, ordered by importance, 104 new trial cards added
- Post-Cardiac Arrest: H's & T's updated to 6 H's and 6 T's (added Hypoglycemia, Trauma)
- Surviving Sepsis Campaign 2026: full guideline names in comparison headers and tabs
- Full structural audit: fixed 163 orphaned sections, 13 duplicate IDs, 4 unclosed topic-tabs, 5 misplaced section blocks
- ~120 missing tab buttons added across 80+ views
- Removed misplaced content: VTE sections from Falls Risk, CKD from GCS, note templates from Radiology, syncope from Valvular HD
- Fixed COPD, OSA, Pneumothorax, Chemotherapy Toxicity, Lymphoma: stray HTML in topic-tabs cleaned
- Upper & Lower GI Bleed: structural fixes, missing tab buttons, expanded content
- QR Poster: real QR code image, updated stats
- Favicon: added favicon.ico for Google indexing, updated manifest with PNG icons
v3.5 -March 28, 2026
- Copyright protection: Terms of Use, domain lock, anti-copy measures, invisible watermarks
- Architecture details removed from About page for security
- Scrollable changelog in About page
- 938 pimp questions — answers shortened for succinct rounds-style delivery
- 18 Antibiotic De-Escalation examples with culture-directed narrowing table
- Sepsis clinical examples expanded: 5 cases with Antibiotic Stewardship guidance
- Pimp questions now in carousel format with indigo theme
- 96 related topic cross-links for improved navigation
- SEO improvements: OG locale, image dimensions, cache headers, sitemap lastmod dates
- Edge function updated for better Google indexing (unique content per URL)
- Structural fixes: 14 unbalanced views, 3 duplicate views, 6 inverted views resolved
- Copyright footer on all pages
v3.4 -March 28, 2026
- 6 topics expanded: DVT Prophylaxis, Contrast Nephropathy, Burns, Tuberculosis, Renal Tubular Acidosis, Dermatomyositis/Polymyositis
- 18 new clinical example carousels with horizontal scroll navigation
- 13 new pimp questions across expanded topics
- 6 new mnemonics: THROMBOSIS (DVT), RIPE + side effects (TB), K+ pattern (RTA), HELIOGRAMS (DM), SHE (PE Virchow triad), 5 I's (DKA)
- New carousel system for clinical case examples
- Improved share button design
- Better social media link previews
- Improved SEO and social sharing
- Updated sidebar design
- Pulmonary Embolism: SHE mnemonic for Virchow triad, smoking added to endothelial injury, removed PERC Rule and Revised Geneva Score
- DKA: 5 I's mnemonic with colored bold letters
- Quick References section added to dashboard overview
v3.3 -March 25, 2026
- Fixed Infective Endocarditis -5 placeholder sections replaced with full clinical content (workup, antibiotics by organism, monitoring, summary)
- Fixed Syncope -4 placeholder sections replaced with management by etiology, medications, monitoring, and disposition criteria
- Fixed Hospice topic -4 corrupted sections (were showing Tumor Lysis/Vasculitis content) replaced with proper hospice content
- Fixed Pericarditis and Aortic Dissection duplicate One Pager placeholders
- Critical bug fix for search and navigation
- Em dashes removed across the website
- Improved search engine visibility
- About page stats updated to reflect actual counts
v3.2 -March 25, 2026
- SSC 2026 guidelines integrated across sepsis topic -all SSC 2018/2021 references updated
- ACS 2025 guidelines added to What's New
- NEWS/MEWS/NEWS2 calculators added (replacing qSOFA per SSC 2026)
- Clinical calculators organized by rotation -Nephrology, Cardiology, Pulmonology, ICU, GI, General
- Media Library -medical movies, documentaries, TV series, and finance books for residents
- Gifted Hands: The Ben Carson Story added to Movies
- Resources page -recommended books section (Oxford Handbook, Harrison's, Pocket Medicine, ICU Book, Guide to IM Workups)
- Resources page -SSC 2026 guidelines added, cleaned up tools and references
- Channels & Podcasts -YouTube and podcast icons replace emojis
- Recently viewed topics in sidebar
- Offline indicator banner
- Share button (WhatsApp, email, text, copy link)
- Black sidebar redesign with improved contrast
- SSC 2026 pimp questions -6 new guideline-specific questions in sepsis topic
- 11 new SSC 2026 pearls added to Pearl of the Day rotation
- Pearl of the Day now starts at random position each page load
- SSC 2026 dashboard banner linking to What's New
- Clean URL routing -SEO-friendly URLs
- Sitemap updated with clean URLs for Google Search Console
- Google Analytics tracks individual page/section views
- RoundsRx logo click returns to dashboard
- Meta description optimized for SSC 2026 search traffic
- Focus outline removed on section navigation
- Diagnostic Dash temporarily removed (under development)
- Google Analytics integration
- Smart back button with navigation history
- Auto-updates on new deployments
- Deployed live at roundsrx.com
v3.1 -March 24, 2026
- Smart search -typo-tolerant search across all topics and drugs
- 41 landmark trials now searchable by name (PARADIGM-HF, DAPA-HF, RALES, etc.)
- Search results scroll directly to matching section and highlight the target
- HFrEF vs HFpEF side-by-side management comparison with 14 trial citations
- STEMI clinical case scenarios with troponin intervals
- Clinical case block styling improvements
v3.0 -March 22, 2026
- 34 clinical worked examples with step-by-step bedside scenarios
- 263 "Updated Practice" callouts flagging old vs new teaching
- 792 trial badges -all with hover descriptions
- 1,775+ drug entries with brand names
- 21 clinical calculators
- New tools: Lab Interpretation Guide, ECG Pattern Guide, Antibiotic Duration Cheat Sheet, IV Fluids Guide, What's New section
- 70+ stub sections replaced with real disease-specific content
- 20+ mislabeled sections corrected (copy-paste errors)
- Fixed corrupted HTML in asthma, HCM topics
- 73 abbreviation definitions added across tables
v2.0 -March 21, 2026
- Expanded to 146 clinical topics across 15 rotations
- 657 pimp questions with reveal answers
- Collapsible sidebar, dark mode, mobile responsive
- SEO optimization, PWA offline support
v1.0 -March 12, 2026
- Initial build: 89 topics across 15 rotations
- Dashboard, search, dark mode
- Offline-capable architecture
Disclaimer
RoundsRx is an educational tool designed to support -not replace -clinical judgment. All content is evidence-based with trial citations, but medicine evolves rapidly. Always verify drug dosing with your pharmacy, confirm guidelines with your institution, and use primary sources (UpToDate, society guidelines, package inserts) for patient care decisions. RoundsRx is not responsible for clinical outcomes.
Credits & Acknowledgments
Built by residents who got tired of flipping between five apps on rounds. Content sourced from major society guidelines (AHA/ACC, KDIGO, IDSA, ATS, AASLD), landmark clinical trials, and UpToDate -then distilled into the format we actually need at 3 AM.
Special thanks to the attendings who pimp relentlessly -you made this necessary.
Contact
Found an error? Have a topic request? Want to contribute? Reach us at RoundsRx@gmail.com. We read every email and prioritize corrections within 24 hours.
Last updated: April 1, 2026 at 12:00 AM
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.
🚨 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). |
| Rituximab | 375 mg/m² weekly × 4 | IV | Anti-CD20. 60% initial response, ~25% durable at 5y. Check HBV before. Arnold, 2007 |
| Fostamatinib | 100-150 mg BID | PO | 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)
- Avoid platelet transfusion unless life-threatening bleeding (transfused platelets destroyed immediately)
- 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").
- Bleeding assessment -skin (petechiae, purpura, ecchymoses), mucosal (oral blood blisters = "wet purpura" = higher bleed risk), menorrhagia, epistaxis, GI, intracranial
- Blood glucose -while on steroids (dexamethasone/prednisone)
- LFTs -q2-4 weeks on eltrombopag (hepatotoxicity risk)
- CBC with differential -monitor for new cytopenias (would suggest secondary cause or MDS)
- Reticulin fibrosis -consider bone marrow biopsy if on TPO-RA > 1 year (rare reversible marrow fibrosis)
- Infection screening -on immunosuppression (rituximab, chronic steroids). HBV reactivation monitoring with rituximab.
📋 Summary
Summary
Definition
Autoimmune platelet destruction. Diagnosis of exclusion. Isolated thrombocytopenia + large platelets.
Workup
CBC + smear (rule out pseudo, TTP, leukemia). HIV, HCV, H. pylori, DAT, coags. BMBx only if atypical.
Treat If
Plt < 30K OR bleeding. Goal: safe platelet count, not normal. Treat patient not number.
First-Line
Dexamethasone 40 mg × 4d or prednisone 1 mg/kg. IVIG 1g/kg if bleeding or plt < 10K.
Second-Line
TPO-RA (eltrombopag, romiplostim), rituximab, fostamatinib. Splenectomy = third-line.
Pearl
Wet purpura = high bleed risk. Evans = ITP + AIHA. Always check smear. Don't BMBx young typical ITP.
📄 One Pager
One-Pager
ITP
Immune Thrombocytopenia
Diagnosis
Isolated thrombocytopenia + large platelets on smear. Normal WBC/Hgb. Rule out: pseudothrombocytopenia (EDTA clumping), TTP (schistocytes), DIC (fibrinogen), HIT (heparin exposure), drug-induced. Check HIV, HCV, H. pylori, DAT.
Treatment Algorithm
Plt ≥ 30K no bleeding → observe. Plt < 30K or bleeding → dexamethasone 40 mg × 4d ± IVIG if severe. Refractory → TPO-RA (eltrombopag/romiplostim) or rituximab. Last resort → splenectomy (vaccinate first).
Key Drugs
IVIG 1g/kg (fastest, 24-48h, transient). Dexamethasone 40 mg × 4d. Eltrombopag 50 mg PO daily. Romiplostim 1-10 mcg/kg SQ weekly. Rituximab 375 mg/m² × 4. Aminocaproic acid for emergency bleeding.
Pitfalls: Don't transfuse platelets unless life-threatening bleed. Don't do BMBx in young typical ITP. Don't chase "normal" platelet count -goal is ≥ 30K.
Trials: ASH ITP Guidelines 2019 · RAISE 2011 · FIT 2018 · Arnold 2007 · Wei 2016
EMERGENTHeme/Onc
Oncologic Emergencies
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.
- Hyperviscosity: Serum viscosity (> 4-5 cP = symptomatic). Fundoscopy ("sausage-link" retinal veins). SPEP + serum free light chains. Peripheral smear (rouleaux).
- Malignant tamponade: Echocardiography (pericardial effusion + RA/RV diastolic collapse). Pulsus paradoxus > 10 mmHg. ECG: low voltage, electrical alternans.
🚨 Management
Management
- 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). |
| Heparin | Weight-based | IV | SVC syndrome with associated thrombus. |
Monitoring
- Neuro exam q4h -for cord compression and brain mets. Motor strength, sensory level, rectal tone, post-void residual. Deterioration = urgent re-imaging.
- Serum viscosity -before and after plasmapheresis. Target < 4 cP.
- Blood glucose -high-dose dexamethasone causes significant hyperglycemia. Sliding scale insulin + glucose checks q6h.
- 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
SVC Syndrome
CT chest w/ contrast. Dex if lymphoma. Radiation or stent. Don't delay for biopsy if severe.
Cord Compression
Dex 10mg IV STAT. MRI entire spine. Radiation ± surgery. Neuro function at dx = prognosis.
Brain Mets
Dex 10mg IV. MRI brain. SRS if ≤4 mets. WBRT if diffuse. No prophylactic AEDs.
Hyperviscosity
Emergent plasmapheresis. No pRBC before pheresis. Fundoscopy. Serum viscosity >4-5.
Tamponade
Echo → pericardiocentesis. Pericardial window if recurrent. 40-70% recurrence rate.
Key Pearl
Dexamethasone first, ask questions later. Most onc emergencies benefit from immediate steroids.
RoundsRx Licensed Content - Unauthorized Use Prohibited📄 One Pager
Hematology
Pancytopenia
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.
🧪 Workup
Workup
- Peripheral smear -the MOST important test. Blasts → leukemia. Teardrop cells + leukoerythroblastic picture → myelofibrosis/marrow infiltration. Dysplastic cells → MDS. Schistocytes → TTP/DIC. Megaloblastic → B12/folate deficiency. Normal morphology → aplastic anemia, drug-induced, viral.
- Reticulocyte count -low = production problem. High (unexpected in pancytopenia) = peripheral destruction + splenic sequestration.
- B12 + folate -megaloblastic anemia can cause pancytopenia (ineffective hematopoiesis)
- LDH, haptoglobin, indirect bilirubin -hemolysis markers
- HIV, HBV, HCV, EBV, CMV, parvovirus B19 -viral marrow suppression
- ANA, RF -autoimmune causes (Felty syndrome = RA + splenomegaly + neutropenia)
- Copper level -copper deficiency mimics MDS (sideroblastic anemia + neutropenia)
- Flow cytometry -if blasts or abnormal lymphocytes on smear
- Bone marrow biopsy + aspirate -definitive test. Hypercellular = MDS, leukemia, megaloblastic. Hypocellular = aplastic anemia. Dry tap = myelofibrosis. Granulomas = infection (TB, fungal). Send: morphology, cytogenetics, flow, iron stain, reticulin stain.
Differential Diagnosis by Mechanism
| Mechanism | Cause | Key Clue |
|---|---|---|
| Decreased Production | Aplastic anemia | Hypocellular marrow, young patient, reticulocyte count low |
| MDS | Elderly, dysplastic cells on smear, cytogenetic abnormalities | |
| Leukemia | Blasts on peripheral smear or bone marrow > 20% | |
| B12/folate deficiency | Megaloblastic changes, hypersegmented neutrophils, elevated MCV | |
| HIV | Risk factors, low CD4, direct marrow suppression | |
| Medications | Methotrexate, chemotherapy, TMP-SMX, linezolid, valproate | |
| Increased Destruction | Hypersplenism | Splenomegaly on exam/imaging, liver disease history |
| HLH | Ferritin > 10,000, fever, splenomegaly, hypertriglyceridemia | |
| TTP/HUS | Schistocytes, elevated LDH, low haptoglobin, renal failure | |
| DIC | Schistocytes, elevated D-dimer, low fibrinogen, prolonged PT/aPTT | |
| Infiltration | Myelofibrosis | Teardrop cells, dry tap, splenomegaly, leukoerythroblastic picture |
| Metastatic cancer | Known primary, leukoerythroblastic smear, bone pain | |
| Storage diseases | Gaucher (glucocerebrosidase deficiency), hepatosplenomegaly |
Peripheral Smear Findings
| Finding | Suggests |
|---|---|
| Blasts | Acute leukemia (AML or ALL) — obtain flow cytometry urgently |
| Teardrop cells | Myelofibrosis — expect dry tap on aspiration, order reticulin stain on biopsy |
| Megaloblastic changes | B12 or folate deficiency — check levels, MMA, homocysteine |
| Schistocytes | TTP/HUS or DIC — check ADAMTS13, fibrinogen, D-dimer, coags |
| Hypersegmented neutrophils | B12 or folate deficiency — ≥ 5 lobes is pathologic |
| Rouleaux formation | Multiple myeloma — check SPEP, serum free light chains |
⚠ When to Do Bone Marrow Biopsy
- Unexplained pancytopenia after initial labs (smear, B12, folate, HIV unrevealing)
- Suspected leukemia or MDS based on clinical picture or smear
- Blasts seen on peripheral smear
- Leukoerythroblastic picture (nucleated RBCs + immature WBCs in periphery)
- Suspected infiltrative process (myelofibrosis, metastatic disease, storage disease)
🚨 Management
Management
- Treat the underlying cause:
- B12 deficiency: IM cyanocobalamin 1000 mcg daily × 7 → weekly × 4 → monthly. Pancytopenia resolves within weeks.
- Drug-induced: Stop offending agent (methotrexate, chemotherapy, TMP-SMX, linezolid, valproate). Recovery in 1-3 weeks typically.
- Aplastic anemia: Age < 40 + matched sibling donor → allogeneic stem cell transplant. Older patients → immunosuppressive therapy: horse ATG + cyclosporine + eltrombopag. RACE, 2022
- MDS: Risk stratify (IPSS-R). Low-risk → ESA, lenalidomide (del5q). High-risk → azacitidine [AZA-001] or transplant if eligible.
- Leukemia: Induction chemotherapy per subtype. APL = ATRA + arsenic trioxide (curative in > 90%).
- HLH: Etoposide-based protocol (HLH-2004). Dexamethasone. Cyclosporine. Treat trigger.
- 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.
❓ What is HLH and how does it present?
Hemophagocytic lymphohistiocytosis (HLH) -uncontrolled immune activation with macrophage phagocytosis of blood cells. Presents with: persistent fever, splenomegaly, pancytopenia, hyperferritinemia (> 500, often > 10,000), hypertriglyceridemia, hypofibrinogenemia, elevated soluble IL-2 receptor. Triggers: infection (EBV), malignancy (lymphoma), autoimmune. Fatal without treatment -etoposide-based protocol. [HLH-2004]
Clinical Examples
📋 Case 1 — Aplastic Anemia
Patient: 25F presenting with fatigue, easy bruising, and recurrent infections over 3 months.
Labs: WBC 1.2, Hgb 6.8, Plt 15K, reticulocyte count 0.2% (inappropriately low), MCV 98.
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.
Labs: WBC 3.1, Hgb 7.2, Plt 95K, MCV 112 (markedly elevated), reticulocyte count 0.8%.
Peripheral smear: Oval macrocytes, hypersegmented neutrophils (6-lobed), anisocytosis, poikilocytosis.
Workup:
- B12: < 100 pg/mL (severely low, normal > 300)
- Methylmalonic acid: elevated (confirms tissue B12 deficiency)
- Homocysteine: elevated
- Anti-intrinsic factor antibodies: positive → pernicious anemia
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).
Labs: WBC 2.4, Hgb 8.5, Plt 68K, LDH elevated.
Peripheral smear: Teardrop cells (dacrocytes), nucleated RBCs, immature myeloid precursors — classic leukoerythroblastic picture.
Workup:
- 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
Definition
Anemia + leukopenia + thrombocytopenia. A lab finding, not a diagnosis.
First Test
Peripheral smear. Blasts=leukemia. Teardrops=fibrosis. Megaloblastic=B12. Dysplastic=MDS.
Key Labs
Retic count, B12/folate, LDH, HIV/HBV/HCV, copper, ANA. Then bone marrow biopsy.
Production ↓
Aplastic anemia, MDS, leukemia, myelofibrosis, B12/folate, drugs, viral, infiltration
Destruction ↑
Hypersplenism, DIC, TTP, HLH, autoimmune
Pearl
Check copper. Hypersegmented neutrophils = B12 (not MDS). Dry tap = myelofibrosis.
📄 One Pager
One-Pager
Pancytopenia
Systematic Approach
Workup Algorithm
Step 1: Peripheral smear (most important). Step 2: Retic count (production vs destruction). Step 3: B12, folate, HIV, HCV, copper. Step 4: Bone marrow biopsy if not explained by above.
Common Causes by Smear
Blasts → leukemia. Teardrops → myelofibrosis. Megaloblastic → B12/folate. Dysplastic → MDS. Schistocytes → TTP. Normal → aplastic anemia, drug, viral.
Trials
RACE 2022 (ATG+CsA+eltrombopag for AA) · AZA-001 2009 (azacitidine for MDS) · HLH-2004 (etoposide protocol) · Scheinberg 2011 (horse vs rabbit ATG)
Heme/OncICU
Chemotherapy Toxicities
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 | Steroids; infliximab if steroid-refractory |
| Hepatitis | AST/ALT elevation, usually asymptomatic | LFTs, hepatitis panel, autoimmune markers, imaging | Steroids; mycophenolate if refractory (NOT infliximab — hepatotoxic) |
| Pneumonitis | Cough, dyspnea, hypoxia | CT chest (ground-glass opacities), PFTs, bronchoscopy/BAL | Hold therapy, high-dose steroids, infliximab or MMF if refractory |
| Endocrine | Thyroiditis → hypothyroidism, adrenal insufficiency, new-onset T1DM, hypophysitis | TSH/free T4, AM cortisol, ACTH, glucose, pituitary MRI | Hormone replacement (levothyroxine, hydrocortisone, insulin) — often lifelong |
| Neuro | Myasthenia gravis, encephalitis, Guillain-Barré, peripheral neuropathy | EMG/NCS, MRI brain, LP, AChR antibodies | High-dose steroids, IVIG, plasmapheresis; permanently discontinue therapy |
| Cardiac | Myocarditis (chest pain, dyspnea, arrhythmia — high mortality) | Troponin, BNP, ECG, echo, cardiac MRI, endomyocardial biopsy | High-dose IV steroids immediately; permanently discontinue; cardiology consult |
Classic Chemo Toxicities — Know the Drug, Know the Organ: Bleomycin = Lungs (pulmonary fibrosis, avoid high FiO₂). Doxorubicin = Heart (dilated cardiomyopathy, lifetime dose limit). Cisplatin = Kidneys + Ears (nephrotoxicity, ototoxicity, neuropathy). Vincristine = Nerves (peripheral neuropathy, constipation/ileus). Cyclophosphamide = Bladder (hemorrhagic cystitis — prevent with MESNA). Methotrexate = Liver + Mucositis (hepatotoxicity, mucositis — rescue with leucovorin).
🧪 Workup
Workup
- Know the regimen -review the chemo protocol. Each drug has specific toxicities.
- CBC with differential -nadir timing varies: 7-14 days for most agents, 4-6 weeks for nitrosoureas
- BMP, LFTs, LDH -organ toxicity screening
- Troponin + BNP + echo -if anthracycline cardiotoxicity suspected
- CT chest -bleomycin/checkpoint pneumonitis
- UA -hemorrhagic cystitis (cyclophosphamide/ifosfamide)
- TSH -checkpoint inhibitor thyroiditis (most common irAE)
- AM cortisol -checkpoint hypophysitis
- Lipase -checkpoint pancreatitis
🚨 Management
Management
- Anthracycline cardiotoxicity: Echo (EF decline > 10% to below 50% = hold). Dexrazoxane for cardioprotection if cumulative dose high. Standard HF therapy if cardiomyopathy develops. Lifetime dose limits: doxorubicin 450-550 mg/m².
- Bleomycin lung toxicity: Stop bleomycin. Steroids (prednisone 1 mg/kg). Avoid high FiO₂ -oxygen worsens bleomycin lung injury (free radical mechanism). Keep SpO₂ 88-92% target.
- Typhlitis (neutropenic enterocolitis): CT abdomen (bowel wall thickening, pneumatosis). Broad-spectrum abx (pip-tazo + vanc). NPO + IV fluids. Surgery if perforation/peritonitis.
- Hemorrhagic cystitis: Aggressive IVF hydration. Continuous bladder irrigation (CBI). MESNA prophylaxis with cyclophosphamide/ifosfamide (binds acrolein metabolite). Urology if severe clot retention.
- Checkpoint inhibitor irAEs: Grade 1 → continue + monitor. Grade 2 → hold checkpoint, prednisone 0.5-1 mg/kg. Grade 3 → hold checkpoint, methylprednisolone 1-2 mg/kg. Grade 4 → permanently discontinue, methylprednisolone 1-2 mg/kg ± infliximab (colitis) or mycophenolate (hepatitis). [NCCN irAE Guidelines]
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| MESNA | 60-100% of cyclophosphamide dose | IV | Prevents hemorrhagic cystitis. Binds acrolein (toxic metabolite) in bladder. Give with cyclo/ifosfamide. |
| Dexrazoxane | 10:1 ratio to doxorubicin | IV | Iron chelator. Cardioprotection for cumulative anthracycline doses ≥ 300 mg/m². |
| Amifostine | 910 mg/m² IV pre-cisplatin | IV | Nephroprotection for cisplatin. Free radical scavenger. Causes hypotension. |
| Prednisone | 1-2 mg/kg daily | PO | irAEs Grade 2+. Taper over 4-6 weeks minimum. Too-rapid taper → flare. |
| Infliximab | 5 mg/kg IV | IV | Steroid-refractory checkpoint colitis. NCCN irAE, 2024 |
| Ondansetron | 8 mg IV pre-chemo | IV | 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?
Grade 1 (AST/ALT 1-3× ULN): continue checkpoint, monitor LFTs weekly. Grade 2 (3-5× ULN): hold checkpoint, prednisone 0.5-1 mg/kg. Grade 3 (5-20× ULN): hold, methylprednisolone 1-2 mg/kg. Grade 4 (> 20× ULN): permanently discontinue, methylprednisolone 2 mg/kg, add mycophenolate (NOT infliximab -hepatotoxic). Rule out viral hepatitis and autoimmune hepatitis first.
❓ What is typhlitis and which patients get it?
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. |
| IV | Extranodal involvement (bone marrow, liver, lung parenchyma) |
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.
Diagnosis: Checkpoint inhibitor thyroiditis → hypothyroid phase.
Key findings:
- 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
Cardiotoxicity
Anthracyclines (doxorubicin). Echo q3mo. Lifetime limit 450-550 mg/m². Dexrazoxane if high dose.
Pulmonary
Bleomycin → fibrosis. Stop drug. Steroids. Avoid high FiO₂ (even years later).
Hemorrhagic Cystitis
Cyclophosphamide/ifosfamide. Prevent with MESNA. Treat with CBI + hydration.
Checkpoint irAEs
Grade 1→monitor. Grade 2→hold+steroids. Grade 3-4→high-dose steroids ± infliximab/MMF.
Typhlitis
Neutropenic cecal inflammation. RLQ pain + fever + ANC<500. CT: cecal wall thickening. Abx + NPO.
Key Rule
Always know the regimen. Each drug has predictable toxicities. Ask: "What chemo did they get?"
📄 One Pager
One-Pager
Chemo Toxicities
Know the drug, predict the toxicity
Drug → Toxicity Map
Anthracyclines → heart. Bleomycin → lungs. Cisplatin → kidneys + ears + nerves. Vincristine → peripheral neuropathy. Cyclophosphamide → bladder. Checkpoint inhibitors → any organ (thyroid most common).
Antidotes/Prevention
MESNA (hemorrhagic cystitis). Dexrazoxane (anthracycline cardiotoxicity). Amifostine (cisplatin nephrotoxicity). Leucovorin (methotrexate rescue). Aggressive hydration (cisplatin, ifosfamide, TLS prevention).
Heme/Onc
Lymphoma
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.
- Pathology: hematoxylin/eosin, immunohistochemistry (CD20, CD3, CD15, CD30, Ki-67), flow cytometry, cytogenetics/FISH
- PET/CT -staging (Ann Arbor). PET-avid = aggressive. PET-negative nodes in follicular lymphoma may still be involved.
- CT chest/abdomen/pelvis -if PET not available
- Bone marrow biopsy -required for NHL staging. Optional for HL with PET/CT (PET replaced BMBx in many centers).
- Labs: CBC, CMP, LDH (prognostic, correlates with tumor burden), uric acid (TLS risk), hepatitis B (reactivation risk with rituximab), HIV (lymphoma association), ESR (HL prognostic factor), β2-microglobulin (NHL prognostic)
- Echocardiography -baseline EF before anthracycline-containing regimens
- Fertility counseling -before starting chemo (especially alkylating agents). Sperm banking / oocyte cryopreservation.
🚨 Management
Management
- Hodgkin Lymphoma:
- Early stage (I-II) favorable: ABVD × 2-4 cycles ± involved-site radiation. Cure rate > 90%.
- Advanced stage (III-IV): ABVD × 6 cycles or BV-AVD (brentuximab-AVD). [ECHELON-1, 2018]
- 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).
- Intern responsibilities: TLS prevention, infection prophylaxis, transfusion support, recognize treatment complications, ensure adequate IV access (port placement), fertility counseling documentation.
Key Chemotherapy Regimens
| Regimen | Components | Used For | Key Toxicities / Pearls |
|---|---|---|---|
| ABVD | Doxorubicin (Adriamycin), Bleomycin, Vinblastine, Dacarbazine | Hodgkin lymphoma (standard first-line) | Bleomycin pulmonary toxicity — monitor PFTs, stop if DLCO drops > 20%. Doxorubicin → cardiomyopathy. q28-day cycles. |
| BV-AVD | Brentuximab vedotin + Doxorubicin, Vinblastine, Dacarbazine | Advanced HL (replacing ABVD in some centers) | No bleomycin = no pulmonary toxicity. Higher neuropathy risk. Requires G-CSF prophylaxis. ECHELON-1, 2018 |
| R-CHOP | Rituximab + Cyclophosphamide, Doxorubicin (Hydroxydaunorubicin), Vincristine (Oncovin), Prednisone | DLBCL (standard first-line) | q21-day cycles × 6. Rituximab added ~15% survival benefit. GELA, 2002 Vincristine → peripheral neuropathy (cap at 2 mg). |
| R-EPOCH | Rituximab + Etoposide, Prednisone, Vincristine, Cyclophosphamide, Doxorubicin (dose-adjusted, continuous infusion) | Double-hit/triple-hit DLBCL, primary mediastinal B-cell lymphoma, Burkitt | 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.
Labs: WBC 11K, Hgb 10.8, ESR 55, LDH 280 (mildly elevated). HIV negative.
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.
Management:
- Pre-chemo: Echo (EF 62%), PFTs (baseline DLCO normal), HBV screen negative, fertility counseling → oocyte cryopreservation.
- ABVD × 6 cycles. Interim PET after cycle 2: Deauville 2 (complete metabolic response).
- Bleomycin dropped after cycle 2 per PET-adapted approach. RATHL, 2016
- End-of-treatment PET: Deauville 1. Complete remission.
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.
Labs: WBC 6K, Hgb 11.2, LDH 580 (elevated — correlates with tumor burden), uric acid 9.2. HBsAg negative, anti-HBc positive.
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).
Management:
- Anti-HBc positive → start entecavir prophylaxis before rituximab (HBV reactivation risk).
- Echo baseline (EF 58%). TLS risk: intermediate → allopurinol + aggressive hydration.
- R-CHOP × 6 cycles (q21 days). GELA, 2002
- IPI score calculated (age > 60, elevated LDH, stage III = IPI 3, high-intermediate risk).
- End-of-treatment PET: Deauville 2. Complete remission. Surveillance CT q6 months × 2 years.
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.
Labs: CBC normal. LDH normal. β2-microglobulin mildly elevated (3.1).
Imaging: PET/CT: mildly FDG-avid bilateral inguinal and external iliac nodes (SUVmax 4). Small mesenteric nodes. No bulky disease.
Biopsy: Excisional inguinal node biopsy: follicular architecture with small cleaved cells. CD20+, CD10+, BCL2+. Ki-67 15%. Grade 1-2. Diagnosis: follicular lymphoma, grade 1-2.
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
- Interim PET/CT -after 2 cycles (HL) or 3-4 cycles (NHL). Complete metabolic response = Deauville 1-3.
- 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
Reed-Sternberg cells. Bimodal. ABVD. Cure > 80%. B symptoms upstage.
DLBCL
Most common aggressive NHL. R-CHOP × 6. Cure 60-70%. CNS prophylaxis if high-risk.
Follicular
Indolent. Watch-and-wait if asymptomatic. Not curable but median survival > 15y.
Workup
Excisional biopsy (never FNA). PET/CT staging. BMBx. LDH, HBV, HIV, echo, PFTs.
Intern Job
TLS prevention. Infection prophylaxis. Transfusion. Recognize complications. Fertility counseling.
Pearl
Screen HBV before rituximab. Don't FNA a node. B symptoms matter. Fertility talk before chemo.
📄 One Pager
One-Pager
Lymphoma
Hodgkin vs Non-Hodgkin
Key Regimens
HL: ABVD (or BV-AVD). DLBCL: R-CHOP. Follicular: rituximab ± bendamustine. Burkitt: intensive regimen + TLS prophylaxis (rasburicase).
Before Starting Chemo
Echo (baseline EF). PFTs (if bleomycin). HBV screen (rituximab reactivation risk). HIV. Fertility counseling. Port placement. TLS risk assessment.
Trials
GELA 2002 (R-CHOP for DLBCL) · ECHELON-1 2018 (BV-AVD for HL) · RELEVANCE (rituximab + lenalidomide for follicular)
EMERGENTEndocrineICU
Hyperosmolar Hyperglycemic State (HHS)
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.
🧪 Workup
Workup
- Fingerstick glucose -often > 600 mg/dL (can exceed 1000). Some glucometers read "HIGH" above 500 → send serum glucose.
- 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)
- Serum osmolality (measured) -> 320 mOsm/kg diagnostic. Calculate: 2×Na + glucose/18 + BUN/2.8. Effective osmolality (excludes BUN): 2×Na + glucose/18 > 320.
- Lactate -hypoperfusion from dehydration
- ECG -rule out MI as trigger. Check for hyperkalemia/hypokalemia changes.
- Lipase -pancreatitis can trigger HHS
Monitoring
🚨 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⁺ < 3.3 → replete BEFORE insulin. If 3.3-5.3 → 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⁺ ≥ 3.3. 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⁺ ≥ 3.3. 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⁺ < 3.3 → 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 ≥ 3.3
- 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 — close the gap)
- 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.
- Fingerstick glucose q1h -target decline 50-70 mg/dL per hour. Faster correction risks cerebral edema.
- 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)
- Serum osmolality q2-4h -target decline ≤ 3 mOsm/kg/hr. If dropping faster → slow IVF rate.
- Urine output q1h -target ≥ 0.5 mL/kg/hr (sign of adequate resuscitation). Foley catheter in ICU.
- Mental status -should improve as osmolality normalizes. If AMS worsens despite improving labs → CT head (stroke may have been the trigger).
- Fluid balance (I&Os) -track meticulously. Goal: replace deficit over 24-48h.
- Resolution criteria: glucose < 300, osmolality < 315, patient alert/eating → transition to SQ insulin. ADA/AACE Consensus, 2009
Monitoring
📋 Summary
Summary
Criteria
Glucose > 600, Osm > 320, pH > 7.30, bicarb > 18, minimal ketones
Fluid Deficit
8-10 L average. NS 1-1.5 L/hr × 1-2h → 250-500 mL/hr. Fluids BEFORE insulin.
Insulin
0.1 U/kg/hr IV (no bolus). Start AFTER fluids + K⁺ ≥ 3.3. Target 50-70 drop/hr.
Trigger
Infection #1 (UTI, PNA). Also: MI, stroke, meds (steroids), non-compliance.
Mortality
5-20% (much higher than DKA). Older patients, worse dehydration, hypercoagulable.
Pearl
Fluids alone drop glucose 75-100/hr. Don't overcorrect osm (< 3/hr). DVT prophylaxis always.
📄 One Pager
One-Pager
HHS
Hyperosmolar Hyperglycemic State
Protocol
Step 1: NS 1-1.5 L/hr × 1-2h (FLUIDS FIRST). Step 2: Check K⁺ -replete if < 3.3 BEFORE insulin. Step 3: Insulin 0.1 U/kg/hr IV (no bolus). Step 4: Treat trigger (infection, MI). Step 5: DVT prophylaxis.
HHS vs DKA
HHS: glucose > 600, osm > 320, no ketoacidosis, T2DM, elderly, 8-10L deficit, mortality 5-20%. DKA: glucose > 250, AG acidosis, ketones, T1DM (or T2), younger, 3-5L deficit, mortality 1-5%.
Danger Zone
Osm correction > 3/hr → cerebral edema. Insulin before fluids → cardiovascular collapse. Insulin before K⁺ → fatal hypokalemia. Stop drip without basal overlap → rebound hyperglycemia.
EMERGENTEndocrineICU
Myxedema Coma
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.
- BMP -hyponatremia (impaired free water excretion → dilutional), hypoglycemia, elevated Cr (decreased renal perfusion)
- 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
Monitoring
🚨 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)
- Fluid resuscitation -cautious (impaired cardiac function). Avoid free water (worsens hyponatremia).
- 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.
- BMP q6-12h -Na⁺ (should improve with T4), glucose (hypoglycemia risk), K⁺
- 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)
Monitoring
📋 Summary
Summary
Triad
AMS + hypothermia + precipitant in untreated hypothyroidism
Step 1
Hydrocortisone 100 mg IV FIRST -rule out concomitant AI before T4
Step 2
T4 200-400 mcg IV load → 50-100 daily. ± T3 5-20 mcg IV q8h.
Labs
TSH sky-high, Free T4 undetectable, Na low, glucose low, pCO₂ high
Mortality
25-60% even with treatment. Elderly women in winter.
Danger
T4 without steroids → adrenal crisis. Active rewarming → cardiovascular collapse.
📄 One Pager
One-Pager
Myxedema Coma
Decompensated Hypothyroidism
Protocol
Step 1: Hydrocortisone 100 mg IV (BEFORE T4). Step 2: T4 200-400 mcg IV load ± T3 5-20 mcg IV q8h. Step 3: Passive rewarming. Step 4: Treat trigger. Step 5: ICU monitoring.
Classic Features
Hypothermia (< 95°F). Bradycardia. AMS → obtundation. Hyponatremia. Hypoglycemia. Hypercapnia. Non-pitting edema. Macroglossia. Delayed DTRs. Periorbital puffiness.
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.
Monitoring
🚨 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
- Alternative: doxazosin 2-8 mg daily (competitive alpha-1 blocker -shorter acting, less reflex tachycardia).
- 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
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Phenoxybenzamine | 10 mg BID → titrate to 20-30 mg BID | PO | Non-competitive alpha-blocker. Start 10-14 days pre-op. Irreversible -long duration. Orthostatic hypotension, nasal congestion, reflex tachycardia. |
| Doxazosin | 2-8 mg daily | PO | 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.
Key findings: Classic paroxysmal triad (headache + diaphoresis + palpitations). Plasma free metanephrines: metanephrine 420 pg/mL (elevated), normetanephrine 2100 pg/mL (markedly elevated). CT: 3.5 cm right adrenal mass, 35 HU.
Management:
- 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.
- BP (standing + seated) daily during alpha-blockade titration -target: seated < 130/80, standing SBP > 90 mmHg (orthostatic tolerance confirms adequate blockade)
- HR -if > 100 on alpha-blocker → start beta-blocker (after adequate alpha-blockade confirmed)
- 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.
Monitoring
📋 Summary
Summary
Triad
Headache + sweating + palpitations with paroxysmal hypertension
Screen
Plasma free metanephrines (sensitivity > 97%). 24h urine for confirmation.
Imaging
CT/MRI adrenal → MIBG or DOTATATE PET for extra-adrenal/metastatic
Treatment
Alpha-block × 10-14d → beta-block → volume expand → surgery.
Never Do
Beta-block alone. Biopsy the mass. Skip genetic testing.
Post-Op
Monitor glucose (hypoglycemia). Metanephrines at 2-4 wk. Annual screening lifelong.
📄 One Pager
One-Pager
Pheochromocytoma
Alpha before Beta. Always.
Pre-Op Protocol
Day 1-14: Phenoxybenzamine 10 mg BID → titrate. Day 10+: Add propranolol ONLY after alpha adequate. Diet: high sodium + fluids. Goal: BP < 130/80 seated, SBP > 90 standing. OR ready: phentolamine + nitroprusside + phenylephrine.
Red Flags
Do NOT biopsy (catecholamine crisis). Do NOT beta-block first (unopposed alpha → crisis). 40% hereditary → always genetic test. Post-op hypoglycemia -monitor glucose q1-2h × 24h.
Trials
Lenders 2014 (plasma metanephrines screening) · Endocrine Society Pheo Guidelines 2014
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?
- BMP -Cr (AKI/CKD reduces insulin clearance → prolonged insulin effect), hepatic function (reduced gluconeogenesis)
- 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
- 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%)
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.
Monitoring
💊 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
- Hypoglycemia event report -many hospitals require formal incident reporting
- Pre-prandial glucose + post-meal check if adjusting regimen -verify effectiveness of changes
- A1c -helps guide discharge insulin regimen (A1c < 7% on insulin = possibly over-basal'd)
Monitoring
📋 Summary
Summary
Definition
Glucose < 70. Level 1: 54-70. Level 2: < 54. Level 3: needs help.
Treat
Alert: 15g carbs PO. Unable to eat: D50 25g IV. No IV: glucagon 1 mg IM. Recurrent: D10 drip.
Prevent
Reduce basal 20-40%. Stop SU in CKD. Hold prandial if NPO. Review all insulin orders.
SU Danger
Recurs × 24-72h (long half-life + CKD). D10 drip + octreotide 50 mcg q6h.
Root Cause
Document: insulin-food mismatch, NPO status, AKI, med error, reduced PO intake.
Pearl
Every hypo event is preventable. The attending will ask what you changed.
📄 One Pager
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.
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).
- PTH (intact) -the diagnostic branch point. Low PTH = hypoparathyroidism (post-surgical, autoimmune, infiltrative). High PTH = secondary hyperparathyroidism (vitamin D deficiency, CKD, PTH resistance).
- 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):
- 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
Monitoring
💊 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).
- 24h urine calcium -for chronic hypoparathyroidism. Target: avoid hypercalciuria (> 300 mg/24h) → nephrolithiasis risk.
- Cr -calcium + vitamin D therapy can worsen renal function. Monitor in CKD patients.
Monitoring
📋 Summary
Summary
Confirm
Ionized Ca (most accurate) or corrected total Ca. Check Mg + PTH + PO₄ + vitamin D.
Emergent
Ca gluconate 1-2g IV/20min → drip. Ca chloride via central only. Correct Mg FIRST.
Low PTH
Hypoparathyroid (post-surgical #1). Rx: calcitriol + oral calcium.
High PTH
Secondary: vitamin D deficiency, CKD. Rx: ergocalciferol or calcitriol.
Post-Surg
Check iCa q6h × 48h after thyroidectomy. Hungry bone = severe prolonged hypoCa.
Pearl
PO₄ high + Ca low = hypopara. PO₄ low + Ca low = vitamin D. Always check Mg.
📄 One Pager
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.
Bedside Tests
Chvostek (tap facial nerve → twitch, 30% specific). Trousseau (BP cuff → carpal spasm, 94% specific). ECG: QTc prolongation → torsades risk.
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.
- 24-hour urine volume -> 3L/day (often 5-15L). UOP > 250 mL/hr should prompt immediate evaluation.
- 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)
- Medication review -lithium, amphotericin B, foscarnet, demeclocycline, cidofovir
🚨 Management
Management
- Central DI:
- 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.
- Low-sodium, low-protein diet -reduces solute load → reduces obligatory urine volume
- 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.
Monitoring - Nephrogenic DI:
💊 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.
- Serum Na⁺ q4-6h -target decline ≤ 10-12 mEq/24h in chronic hypernatremia. Faster correction → cerebral edema.
- Urine osmolality -rising Uosm on DDAVP confirms central DI and response to therapy.
- Daily weights + strict I&Os -fluid balance critical
- 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
Monitoring
📋 Summary
Summary
Diagnosis
Polyuria > 3L/day + dilute urine (Uosm < 300) + high serum osm. DDAVP challenge differentiates central vs nephrogenic.
Central DI
DDAVP (intranasal/PO/IV). Post-surgical #1. Responds to exogenous ADH.
Nephrogenic DI
Remove cause (lithium, hypercalcemia). Thiazide + amiloride (lithium). Low-Na diet.
Triphasic
DI → SIADH → permanent DI post-pituitary surgery. Stop DDAVP if UOP drops.
Replacement
FWD = TBW × [(Na/140)−1]. Replace 50% in 24h. Na correction ≤ 10-12 mEq/24h.
Pearl
Absent bright spot on MRI T1 = central DI. Thiazides are paradoxically helpful in NDI.
📄 One Pager
One-Pager
Diabetes Insipidus
Central vs Nephrogenic
DDAVP Challenge
Give DDAVP 2 mcg IV → measure Uosm. Rises > 50% = central (responds). No change = nephrogenic (resistant). Copeptin: low = central DI.
Treatment
Central: DDAVP + free water. Nephrogenic: remove cause + thiazide + amiloride (lithium) + low-Na diet. ICU: match UOP with D5W mL-for-mL.
Endocrine
Cushing's Syndrome
Chronic cortisol excess. Most common cause: exogenous steroids. Most common endogenous cause: pituitary adenoma (Cushing's disease). Systematic biochemical → localization approach.
🔍 Overview
Overview
Cushing's syndrome = clinical manifestations of chronic cortisol excess. Exogenous (iatrogenic steroids) is by far the most common cause overall. Among endogenous causes: Cushing's disease (ACTH-secreting pituitary adenoma, ~70%), ectopic ACTH (small cell lung cancer, carcinoid, ~15%), adrenal adenoma/carcinoma (~15%). Classic features: central obesity, moon facies, dorsal fat pad (buffalo hump), violaceous striae (> 1 cm wide), proximal muscle weakness, easy bruising, hyperglycemia, HTN, osteoporosis, hirsutism, menstrual irregularity, depression/psychosis. Key teaching point: the workup is a 3-step process -(1) confirm hypercortisolism, (2) determine ACTH dependence, (3) localize the source.
🧪 Workup
Workup
- Step 1 -Confirm hypercortisolism (need 2 of 3 tests positive):
- 24-hour urine free cortisol (× 2) -elevated > 3× ULN is virtually diagnostic. Mild elevations can be false positive (pseudo-Cushing: alcoholism, depression, obesity).
- Late-night salivary cortisol (× 2) -loss of diurnal cortisol rhythm. Cortisol should nadir at 11 PM. Elevated = abnormal. Convenient outpatient test.
- 1 mg overnight dexamethasone suppression test (DST) -give dex 1 mg PO at 11 PM → check 8 AM cortisol. Normal: cortisol < 1.8 mcg/dL (suppressed). Cushing's: cortisol fails to suppress (> 1.8). Nieman, 2008
- Step 2 -ACTH level (determine dependence):
- ACTH elevated (> 20 pg/mL) → ACTH-dependent: pituitary (Cushing's disease) vs ectopic ACTH
- ACTH suppressed (< 5 pg/mL) → ACTH-independent: adrenal source (adenoma, carcinoma, bilateral hyperplasia)
- Step 3 -Localize:
- 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)
- Ectopic ACTH: CT chest/abdomen (small cell, carcinoid, thymic tumors). Octreotide scan. PET/CT.
Monitoring
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Ketoconazole | 200-400 mg BID-TID | PO | Steroidogenesis inhibitor. Most commonly used medical therapy. Monitor LFTs (hepatotoxicity). QTc prolongation. Drug interactions (CYP3A4). |
| Metyrapone | 250-750 mg TID-QID | PO | 11β-hydroxylase inhibitor. Blocks cortisol synthesis. Can cause hyperandrogenism (hirsutism, acne). Monitor cortisol + ACTH. |
| Osilodrostat | 2-7 mg BID | PO | 11β-hydroxylase inhibitor. Newer. LINC-3, 2022. QTc monitoring. Adrenal insufficiency risk. |
| Mifepristone | 300-1200 mg daily | PO | GR antagonist. FDA-approved for Cushing's-associated hyperglycemia. Cannot monitor cortisol (blocked receptor). Monitor clinically. SEISMIC, 2012 |
| Pasireotide | 0.6-0.9 mg SQ BID | SQ | Somatostatin analog for Cushing's disease. Hyperglycemia is major side effect (up to 70%). |
| Mitotane | 2-6 g/day (titrate) | PO | Adrenolytic -for adrenal carcinoma. Causes AI (needs replacement). Monitor levels (target 14-20 mcg/mL). Teratogenic. |
🏥 Rounds
Pimp Questions
❓ What are the 3 steps in the Cushing's workup?
Step 1: Confirm hypercortisolism -2 of 3 positive: 24h UFC, late-night salivary cortisol, 1 mg DST. Step 2: ACTH level -high = ACTH-dependent (pituitary or ectopic), low = ACTH-independent (adrenal). Step 3: Localize -MRI pituitary (if ACTH-dependent) or CT adrenals (if ACTH-independent). IPSS if pituitary MRI equivocal. Nieman, 2008
❓ 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.
Key findings: 24h UFC 420 mcg (4× ULN), late-night salivary cortisol elevated, 1 mg DST cortisol 14.2 (failed suppression). ACTH 72 pg/mL (elevated → ACTH-dependent). MRI pituitary: 7 mm adenoma.
Management:
- Confirm ACTH-dependent Cushing's: high-dose DST (8 mg) → > 50% suppression supports pituitary source
- Referral for transsphenoidal surgery (TSS) — first-line, cure rate 70-90% for microadenomas
- Pre-op: insulin for hyperglycemia, VTE prophylaxis (Cushing's is hypercoagulable), PCP prophylaxis with TMP-SMX
- Post-op: expect adrenal insufficiency (start hydrocortisone 15-20 mg/day, taper over months)
- 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.
Management:
- Aggressive K⁺ replacement + spironolactone (mineralocorticoid excess from cortisol overwhelming 11β-HSD2)
- 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).
- 24h urine free cortisol -to monitor treatment response. Target: normalization.
- 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)
Monitoring
📋 Summary
Summary
Step 1
Confirm: 24h UFC + salivary cortisol + 1mg DST (need 2/3 positive)
Step 2
ACTH: High → pituitary or ectopic. Low → adrenal.
Step 3
Localize: MRI pituitary (high ACTH) or CT adrenals (low ACTH). IPSS if equivocal.
Treatment
TSS for Cushing's disease (cure 65-90%). Adrenalectomy for adrenal tumors. Medical if inoperable.
Post-Op
Expect AI → hydrocortisone until HPA recovery (6-18 months). Check AM cortisol periodically.
Pearl
Wide purple striae + proximal weakness = Cushing's, not obesity. #1 cause overall = exogenous steroids.
📄 One Pager
One-Pager
Cushing's Syndrome
Confirm → ACTH → Localize
3-Step Workup
1. Confirm: 24h UFC, late-night salivary cortisol, 1mg DST (2/3 positive). 2. ACTH: high = pituitary/ectopic, low = adrenal. 3. Localize: MRI pituitary or CT adrenals. IPSS if MRI equivocal.
Trials
Nieman 2008 (Endocrine Society Guidelines) · LINC-3 2022 (osilodrostat) · SEISMIC 2012 (mifepristone)
Endocrine
Hyperthyroidism / Graves' Disease
Graves' = most common cause of hyperthyroidism. TSI-mediated thyroid stimulation. Treatment: thionamides, RAI, or surgery. Know when each is preferred.
🔍 Overview
Overview
Hyperthyroidism = excessive thyroid hormone production/release. Causes: Graves' disease (70-80% -autoimmune, TSI stimulates TSH receptor), toxic multinodular goiter (elderly, autonomous nodules), toxic adenoma (single hot nodule), thyroiditis (subacute/painless -transient release of preformed hormone, NOT overproduction), exogenous thyroid hormone, iodine-induced (Jod-Basedow). Graves' has unique extra-thyroidal features: Graves' ophthalmopathy (proptosis, lid lag, diplopia -25-50%), pretibial myxedema (localized dermopathy), thyroid acropachy (digital clubbing). Symptoms: anxiety, tremor, weight loss, heat intolerance, palpitations (AF in 10-15%), diarrhea, menstrual irregularity, hyperreflexia.
🧪 Workup
Workup
- 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.
- Radioactive iodine uptake (RAIU) -differentiates causes:
- Diffusely elevated = Graves'
- Focal hot nodule (suppressed rest) = toxic adenoma
- Patchy = toxic multinodular goiter
- Low/absent uptake = thyroiditis (preformed hormone release, not production), exogenous, or iodine excess
- ESR/CRP -elevated in subacute (de Quervain) thyroiditis (painful + elevated inflammatory markers)
- CBC -baseline before starting thionamides (agranulocytosis risk)
- LFTs -baseline before thionamides (PTU → hepatotoxicity)
- ECG -atrial fibrillation (10-15% of hyperthyroid patients). Often rate-controlled with beta-blockers alone.
- Thyroid ultrasound -if nodule palpated or RAIU shows focal uptake. Evaluate for suspicious features.
🚨 Management
Management
- Beta-blocker (ALL patients, symptom control): Propranolol 20-40 mg TID-QID (preferred -also blocks T4→T3 conversion) or atenolol 50-100 mg daily. Continue until euthyroid.
- Graves' disease -3 treatment options:
Monitoring
💊 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. |
| Radioactive iodine (I-131) | Per nuclear medicine calculation | PO | Definitive. Causes permanent hypothyroidism (expected outcome). Avoid pregnancy × 6 months after. Worsen ophthalmopathy → prednisone cover. |
| SSKI (saturated KI) | 1-2 drops TID | PO | 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.
- Post-thyroidectomy: Check calcium q6h × 48h (hypoparathyroidism risk). Start levothyroxine. Check TSH at 6 weeks.
- Ophthalmopathy assessment -active inflammation = orbital CT/MRI, refer ophthalmology. IV methylprednisolone for moderate-severe active orbitopathy [EUGOGO].
Monitoring
📋 Summary
Summary
Diagnosis
TSH suppressed + FT4/FT3 high. TSI/TRAb for Graves'. RAIU differentiates all causes.
Graves' Rx
Methimazole 12-18 mo trial (40% remission), RAI (definitive), or surgery.
Thyroiditis
Low RAIU. Self-limited. Beta-blockers only. Thionamides are useless.
Pregnancy
PTU in 1st trimester → methimazole after. Lowest dose. No RAI ever.
Emergency
Agranulocytosis: fever + sore throat → STAT CBC → stop thionamide → admit.
Pearl
RAI worsens ophthalmopathy (give prednisone cover). Propranolol also blocks T4→T3.
📄 One Pager
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)
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. PASO, 2017
🧪 Workup
Workup
- Step 1 -Screening (ARR): Plasma aldosterone concentration (PAC) / plasma renin activity (PRA) = aldosterone-to-renin ratio. ARR > 30 with PAC ≥ 10-15 ng/dL = positive screen. Draw morning, seated, K⁺-repleted. Hold interfering medications: spironolactone × 6 weeks, eplerenone × 6 weeks, ACEi/ARB acceptable (may cause false negatives). Endocrine Society, 2016
- Who to screen: Resistant HTN (≥ 3 drugs), HTN + hypokalemia, HTN + adrenal incidentaloma, HTN onset < 40, severe HTN (≥ 160/100), HTN + family history of early stroke or PA
- Step 2 -Confirmatory test (suppress aldosterone):
- 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 -cures hypokalemia in nearly all, cures or improves HTN in 50-80%. 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
- Adjunct: Sodium restriction (< 2g/day), additional antihypertensives as needed (CCB, thiazide)
- 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
💊 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. PASO, 2017
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%)
- Start spironolactone 50 mg daily while awaiting AVS (treats HTN + replaces K⁺)
- 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)
- Target BP < 130/80, K⁺ 4.0-5.0
- Low-sodium diet (< 2g Na/day) — amplifies MRA efficacy
- 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.
Monitoring
📋 Summary
Summary
Screen
ARR > 30 + PAC ≥ 10-15. Morning, seated, K⁺-repleted. Hold spironolactone × 6 wk.
Confirm
Saline infusion (PAC > 10 post), oral salt loading (urine aldo > 12), or fludrocortisone.
Localize
CT adrenals + AVS (gold standard). CT alone is wrong 38%.
APA (Conn's)
Laparoscopic adrenalectomy. Cures K⁺. Cures/improves HTN 50-80%.
BAH
Spironolactone 25-100 mg or eplerenone 50-100 BID. Low-Na diet. Monitor K⁺.
Pearl
Most PA patients are normokalemic. CV damage exceeds BP-matched essential HTN.
📄 One Pager
One-Pager
Primary Aldosteronism
Screen → Confirm → Localize
3-Step Workup
Screen: ARR > 30 + PAC ≥ 10. Confirm: saline infusion (PAC > 10 post). Localize: CT adrenals + AVS (gold standard, CT wrong 38%). Lateralization ≥ 4:1 → surgery.
Trials
Endocrine Society PA Guidelines 2016 · PATHWAY-2 2015 (spironolactone best add-on for resistant HTN) · PASO 2017 (PA cardiovascular outcomes)
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.
🔍 Overview
Overview
Hypothyroidism = insufficient thyroid hormone production. Primary (> 95%): thyroid gland failure -TSH high, FT4 low. Central (< 5%): pituitary or hypothalamic disease -TSH low/normal, FT4 low. Hashimoto's thyroiditis (chronic autoimmune) is the #1 cause in iodine-sufficient countries. Other causes: post-RAI, post-thyroidectomy, post-radiation, medications (amiodarone, lithium, checkpoint inhibitors), iodine deficiency (worldwide), infiltrative (sarcoidosis, hemochromatosis). Prevalence: 5-10% (overt + subclinical). Subclinical hypothyroidism: TSH elevated (4.5-10), FT4 normal. Treatment controversial -treat if: TSH > 10, symptoms, pregnancy/planning pregnancy, positive TPO antibodies with TSH > 7. Symptoms: fatigue, cold intolerance, weight gain, constipation, dry skin, hair loss, menorrhagia, depression, myalgias, delayed DTRs.
🧪 Workup
Workup
- 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.
- CBC -normocytic or macrocytic anemia is common
- BMP -hyponatremia (impaired free water excretion), elevated Cr (decreased renal perfusion)
- 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
Monitoring
💊 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.
Key findings: Overt primary hypothyroidism (elevated TSH + low FT4). Hashimoto thyroiditis confirmed by strongly positive TPO antibodies. Symptomatic.
Management:
- Levothyroxine 1.6 mcg/kg/day (full replacement dose in young, healthy patient) — ~88 mcg daily
- Take on empty stomach, 30-60 min before breakfast. Avoid calcium, iron, PPI within 4 hours
- Recheck TSH in 6-8 weeks (steady state requires 5-6 half-lives; T4 t½ = 7 days)
- Goal TSH 0.5-2.5 mIU/L (lower half of normal range for symptomatic patients)
- Screen for associated autoimmune conditions: celiac (10% co-occurrence), B12 deficiency, adrenal insufficiency
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
- ICU admission, intubate if GCS ≤ 8, avoid sedatives (prolonged metabolism)
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).
Monitoring
📋 Summary
Summary
Diagnosis
TSH high + FT4 low = primary overt. TSH high + FT4 normal = subclinical. Check TPO Ab.
Treatment
Levothyroxine 1.6 mcg/kg/day. Empty stomach, 30-60 min before food. Separate Ca, Fe, PPI by 4h.
Monitoring
TSH at 6-8 weeks after dose change. Target 0.5-2.5 (elderly: 3-6). Annual once stable.
Subclinical
Treat if: TSH > 10, pregnant, goiter, symptoms + TPO positive, TSH 7-10 + TPO positive.
Pregnancy
Increase dose 25-50% early. Target TSH < 2.5 first trimester. Monthly TFTs.
Pearl
#1 cause of refractory elevated TSH = non-compliance. Central hypothyroidism: monitor FT4, not TSH.
📄 One Pager
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
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
- BMP -hypercalcemia, renal insufficiency (light chain cast nephropathy -"myeloma kidney")
- Albumin + β2-microglobulin -ISS staging: Stage I (β2M < 3.5, alb ≥ 3.5), Stage III (β2M ≥ 5.5). R-ISS, 2015
- LDH -elevated = high tumor burden/aggressive biology
- Bone marrow biopsy + aspirate -≥ 10% clonal plasma cells = myeloma. Send cytogenetics/FISH: high-risk features: del(17p), t(4;14), t(14;16), gain(1q), del(1p).
- 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).
- Quantitative immunoglobulins -immune paresis (suppression of uninvolved Ig classes → infection risk)
- Viscosity -if IgM or very high M-protein (hyperviscosity rare in IgG myeloma, more common in Waldenström)
🚨 Management
Management
- Transplant-eligible (< 70, good performance): Induction → stem cell collection → autologous stem cell transplant (ASCT) → maintenance. Standard induction: VRd (bortezomib/lenalidomide/dexamethasone) × 3-4 cycles. [SWOG S0777, 2017]. Post-ASCT maintenance: lenalidomide until progression. DETERMINATION, 2022
- Transplant-ineligible: VRd (dose-adjusted) or DRd (daratumumab/lenalidomide/dex) until progression. MAIA, 2019
- Supportive care (intern-critical):
- Bone disease: Zoledronic acid 4 mg IV q4 weeks (or denosumab if CrCl < 30). Reduces skeletal events. Check dental clearance first (ONJ risk).
- Infection prophylaxis: Acyclovir (VZV on bortezomib), TMP-SMX or levofloxacin first 3 months, IVIG if recurrent infections with hypogammaglobulinemia
- VTE prophylaxis: Lenalidomide + dex → aspirin (low risk) or LMWH/DOAC (high risk: prior VTE, obesity, immobility)
- Renal protection: Aggressive hydration, avoid NSAIDs and contrast if possible, treat hypercalcemia
- Pain: Radiation for focal bone pain, vertebroplasty/kyphoplasty for compression fractures
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Bortezomib | 1.3 mg/m² SQ weekly | SQ | Proteasome inhibitor. Peripheral neuropathy (dose-limiting). VZV reactivation → acyclovir prophylaxis. SWOG S0777, 2017 |
| Lenalidomide | 25 mg PO days 1-21/28 | PO | IMiD. VTE risk → thromboprophylaxis. Teratogenic. Dose-reduce for CrCl < 30. Maintenance post-ASCT: 10-15 mg. |
| Daratumumab | 16 mg/kg IV weekly → q2w → q4w | IV/SQ | 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. |
Monitoring
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Bortezomib | 1.3 mg/m² SQ weekly | SQ | Proteasome inhibitor. Peripheral neuropathy (dose-limiting). VZV reactivation → acyclovir prophylaxis. SWOG S0777, 2017 |
| Lenalidomide | 25 mg PO days 1-21/28 | PO | IMiD. VTE risk → thromboprophylaxis. Teratogenic. Dose-reduce for CrCl < 30. Maintenance post-ASCT: 10-15 mg. |
| Daratumumab | 16 mg/kg IV weekly → q2w → q4w | IV/SQ | 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)
- Start VRd induction: bortezomib + lenalidomide (renal dose) + dexamethasone SWOG S0777, 2017
- 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.
Management:
- VRd induction × 3-4 cycles → stem cell collection → high-dose melphalan + autologous SCT (ASCT)
- 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)
- No treatment unless CRAB or SLiM criteria develop
- 20/2/20 risk model: 2+ risk factors (plasma cells > 20%, M-spike > 2 g/dL, sFLC ratio > 20) = high-risk smoldering
- 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.
- SPEP + sFLC q1-2 cycles -track M-protein decline (response criteria: CR, VGPR, PR per IMWG)
- 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.
Monitoring
📋 Summary
Summary
Diagnosis
SPEP + sFLC + BMBx. ≥ 10% clonal plasma cells + CRAB or SLiM criteria.
CRAB
C alcium > 11 · R enal Cr > 2 · A nemia Hgb < 10 · B one lytic lesions
Treatment
VRd induction ± ASCT (if eligible) → lenalidomide maintenance. DRd if transplant-ineligible.
Supportive
Zoledronic acid, acyclovir (bortezomib), VTE prophylaxis (lenalidomide), IVIG if recurrent infections.
High Risk
del(17p), t(4;14), t(14;16), gain(1q). Worse prognosis → intensify therapy.
Pearl
Notify blood bank before daratumumab. Myeloma kidney = light chain casts. Avoid NSAIDs + contrast.
📄 One Pager
One-Pager
Multiple Myeloma
CRAB + SLiM
Workup
SPEP/UPEP + immunofixation + sFLC + BMBx (cytogenetics/FISH) + skeletal survey (PET/CT preferred) + β2M/albumin (ISS staging) + quantitative Ig.
Treatment
Eligible: VRd × 3-4 → ASCT → lenalidomide maintenance. Ineligible: DRd or VRd continuous. Supportive: zoledronic acid, acyclovir, VTE prophylaxis, hydration.
Trials
SWOG S0777 (VRd) · MAIA 2019 (DRd) · DETERMINATION 2022 (ASCT role) · IMWG 2014 (diagnostic criteria)
EMERGENTHeme/OncICU
Acute Leukemia (AML / ALL)
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).
- Coags + fibrinogen -DIC screen (especially APL). If DIC + blasts → start ATRA immediately.
- BMP + uric acid + LDH + phosphate -TLS risk assessment
- G6PD -before rasburicase
- Type & screen -will need multiple transfusions
- HLA typing -early if transplant candidate (start sibling/unrelated donor search)
- Lumbar puncture -ALL requires CNS staging (LP with intrathecal chemotherapy). AML: LP only if CNS symptoms.
- Echo -baseline EF before anthracycline-containing induction
- Infectious workup -blood/urine cultures, CXR, consider fungal markers if prolonged neutropenia expected
RoundsRx Licensed Content - Unauthorized Use Prohibited🚨 Management
Management
- APL (M3 AML) -EMERGENCY: Start ATRA (all-trans retinoic acid) immediately if APL suspected (Auer rods, DIC, promyelocytic morphology). Do NOT wait for FISH confirmation. ATRA + arsenic trioxide (ATO) cures > 90% of APL. Lo-Coco, 2013
- AML induction: "7+3" -cytarabine 7 days + daunorubicin 3 days. Targeted: add midostaurin if FLT3+ RATIFY, 2017, gemtuzumab ozogamicin if CD33+ favorable risk. Unfit elderly: azacitidine + venetoclax VIALE-A, 2020.
- ALL induction: Multi-agent (vincristine, prednisone, daunorubicin, asparaginase ± cyclophosphamide). Ph+ ALL: add dasatinib or ponatinib (TKI) [GRAAPH-2005]. CNS prophylaxis with intrathecal methotrexate.
- Consolidation → Transplant: Intermediate/high-risk AML and high-risk ALL → allogeneic stem cell transplant in CR1.
- Intern-managed complications:
- TLS prevention: Aggressive IVF + allopurinol (prophylaxis) or rasburicase (treatment/high-risk). Check TLS labs q6-8h.
- Leukostasis (WBC > 100K): Emergent leukapheresis + hydroxyurea 50-100 mg/kg. Symptoms: dyspnea, confusion, visual changes (WBC plugging microvasculature).
- 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.
Monitoring
🏥 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)
- Arsenic trioxide (ATO) + ATRA for low-risk APL (WBC < 10K) Lo-Coco, 2013
- 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
- Coags + fibrinogen daily -especially APL. Keep fibrinogen > 100-150 with cryoprecipitate.
- Daily assessment: fever curve, exam (skin for leukemia cutis, gums for infiltration, fundoscopy for leukostasis, neuro for CNS leukemia)
- Day 14 bone marrow (AML) -assess for residual disease. If persistent blasts → may need re-induction.
- QTc -on arsenic trioxide. Hold if QTc > 500 ms. Correct K⁺ and Mg²⁺ aggressively.
- Cerebellar function -on high-dose cytarabine. Dysarthria, ataxia, nystagmus → stop immediately (irreversible).
- MRD (measurable residual disease) -flow cytometry or molecular testing post-induction. Guides consolidation/transplant decision.
Monitoring
📋 Summary
Summary
Diagnosis
≥ 20% blasts in marrow/blood. Flow + cytogenetics + FISH + molecular testing.
APL
ATRA + ATO immediately. Auer rods + DIC. Cure > 90%. Do NOT wait for FISH.
AML
7+3 (cytarabine + daunorubicin). Add midostaurin if FLT3+. Unfit: aza + venetoclax.
ALL
Multi-agent induction + CNS prophylaxis. Add TKI if Ph+. Transplant for high-risk.
Intern Role
TLS prevention, febrile neutropenia, DIC management, transfusion support, electrolytes.
Pearl
WBC > 100K = leukostasis risk → leukapheresis + hydroxyurea. Don't transfuse pRBC first.
📄 One Pager
One-Pager
Acute Leukemia
AML / ALL / APL
APL Emergency
Auer rods + DIC → start ATRA now. Don't wait for FISH. Cryoprecipitate for fibrinogen > 150. ATRA + arsenic trioxide cures > 90%.
Trials
Lo-Coco 2013 (ATRA+ATO for APL) · RATIFY 2017 (midostaurin for FLT3+ AML) · VIALE-A 2020 (aza+venetoclax)
Hematology
Anticoagulation Management
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.
🧪 Workup
Workup
- Before starting anticoagulation: CBC, PT/INR, aPTT, Cr + CrCl (DOAC dosing), LFTs (hepatic clearance), HAS-BLED score (bleeding risk)
- 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).
- LMWH: No routine monitoring. Check anti-Xa level (peak, 4h post-dose) if: obesity (> 150 kg), CKD (CrCl < 30 → use UFH instead), pregnancy.
- 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).
- Indication verification: AF (CHA₂DS₂-VASc ≥ 2 men, ≥ 3 women), VTE treatment, mechanical valve (warfarin only), antiphospholipid syndrome (warfarin preferred over DOACs TRAPS, 2018)
🚨 Management
Management
- 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.
- Perioperative bridging:
- Most patients: do NOT bridge. BRIDGE, 2015 -bridging with LMWH in AF patients on warfarin increased bleeding without reducing thrombosis.
- Bridge ONLY if: mechanical mitral valve, mechanical aortic valve + additional risk factor, VTE within 3 months, prior thrombosis during anticoagulation interruption.
- Stop warfarin 5 days before. Stop DOAC 2-3 days before (longer if CKD). Resume 24-72h post-procedure depending on bleeding risk.
- 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
- Xa inhibitors (rivaroxaban/apixaban/edoxaban): Andexanet alfa (Andexxa) -expensive, limited availability. Alternative: 4-factor PCC 50 units/kg. ANNEXA-4, 2019
- Heparin: Protamine 1 mg per 100 units UFH given in last 2-3h (max 50 mg). Only 60% effective for LMWH.
💊 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. |
Monitoring
🏥 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.
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.
- 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.
- Bleeding assessment: signs (hemoglobin drop, melena, hematuria, bruising), drug interactions (NSAIDs, antiplatelets, CYP3A4 inhibitors)
- 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).
Monitoring
📋 Summary
Summary
AF
DOAC preferred. CHA₂DS₂-VASc ≥ 2M/≥3F → anticoagulate. Warfarin only for mechanical valve or APS.
VTE
DOAC preferred. 3 mo (provoked) vs extended (unprovoked). Cancer: LMWH or DOAC.
Bridging
Most: do NOT bridge BRIDGE, 2015. Bridge only: mechanical valve, VTE < 3 mo.
Reversal
Warfarin: 4F-PCC + vit K. Dabigatran: idarucizumab. Xa: andexanet or 4F-PCC. Heparin: protamine.
Monitoring
Warfarin: INR. Heparin: aPTT q6h. LMWH: anti-Xa (special). DOACs: Cr annually.
Pearl
DOACs contraindicated in APS [TRAPS] + mechanical valves [RE-ALIGN]. Rivaroxaban with food.
📄 One Pager
One-Pager
Anticoagulation
Choose, dose, reverse
Agent Selection
AF/VTE: DOAC first-line. Mechanical valve: warfarin only. APS (triple-positive): warfarin only. Cancer VTE: LMWH or DOAC. Acute inpatient: UFH (titratable) or LMWH.
Reversal Agents
Warfarin → 4F-PCC + vit K. Dabigatran → idarucizumab 5g IV. Xa inhibitors → andexanet alfa or 4F-PCC 50 U/kg. UFH → protamine. LMWH → protamine (partial).
Trials
BRIDGE 2015 · RE-LY · ROCKET AF · ARISTOTLE · TRAPS 2018 · RE-VERSE AD · ANNEXA-4 · HOKUSAI VTE Cancer
Hematology
Anemia Workup
Systematic MCV-based approach: microcytic (iron deficiency #1), normocytic (chronic disease, hemolysis, bleeding), macrocytic (B12/folate, MDS, alcohol). Every anemia deserves a reticulocyte count.
🔍 Overview
Overview
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).
🧪 Workup
Workup
- Step 1 -CBC + reticulocyte count + peripheral smear
- Reticulocyte index > 2%: marrow is responding → blood LOSS or DESTRUCTION (hemolysis)
- Reticulocyte index < 2%: marrow failure → production problem
- Step 2 -MCV-based workup:
- Microcytic: Iron studies (ferritin, TIBC, serum iron, transferrin sat). Ferritin < 30 = iron deficiency (in inflammation: ferritin < 100 is likely iron deficient). Thalassemia: Mentzer index (MCV/RBC < 13 = thalassemia trait), Hgb electrophoresis.
- Normocytic: BMP (CKD), CRP/ESR (chronic disease), hemolysis labs (LDH, haptoglobin, indirect bili, DAT), reticulocyte count. If hemolysis: Coombs positive = autoimmune (AIHA). Coombs negative = mechanical (TTP, DIC, valve), PNH, G6PD, sickle cell.
- Macrocytic: B12 + folate (if equivocal: methylmalonic acid for B12, homocysteine for both). TSH. LFTs. Peripheral smear (hypersegmented neutrophils = megaloblastic). Consider bone marrow biopsy if unexplained (MDS).
- Iron studies interpretation:
- Iron deficiency: ferritin ↓, TIBC ↑, iron ↓, TfSat < 20%
- Chronic disease: ferritin ↑ (or normal), TIBC ↓, iron ↓, TfSat 15-20%
- 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 |
Monitoring
🏥 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?
Target cells: thalassemia, iron deficiency, liver disease. Schistocytes: TTP, DIC, mechanical valve hemolysis. Spherocytes: autoimmune hemolysis (AIHA), hereditary spherocytosis. Hypersegmented neutrophils: B12/folate deficiency (megaloblastic). Teardrop cells + leukoerythroblastic: myelofibrosis/marrow infiltration. Sickle cells: SCD. Rouleaux: myeloma, inflammation. Bite cells/Heinz bodies: G6PD deficiency.
Clinical Examples
📋 Case 1 — Iron Deficiency with Occult GI Malignancy
Patient: 62-year-old postmenopausal woman presents with fatigue and exertional dyspnea over 3 months. No overt bleeding. PMH: GERD on omeprazole.
Key findings: Hgb 7.8, MCV 68, ferritin 6, TIBC 480, TfSat 5%, reticulocyte index 0.4%. Smear: microcytic hypochromic RBCs, pencil cells. FIT positive.
Management:
- Transfuse 1 unit pRBC (symptomatic, Hgb < 7 threshold) TRICC, 1999
- IV iron (ferric carboxymaltose 750 mg x 2 doses)
- 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.
Key findings: Hgb 8.0, MCV 118, WBC 3.2, platelets 110 (pancytopenia). Smear: macro-ovalocytes, hypersegmented neutrophils. B12 undetectable, methylmalonic acid markedly elevated.
Management:
- 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.
Monitoring
📋 Summary
Summary
Step 1
CBC + reticulocyte count + peripheral smear. Retic high = loss/destruction. Low = production.
Microcytic
Iron studies. Ferritin < 30 = iron deficient. Ferritin 30-100 with inflammation = likely iron deficient. Mentzer < 13 = thalassemia.
Normocytic
CKD (EPO), chronic disease (CRP), hemolysis (LDH, hapto, DAT), bleeding (retic + guaiac).
Macrocytic
B12 + folate + TSH + LFTs. Hypersegmented neutrophils = megaloblastic. MDS if unexplained.
Iron Rx
Oral: every other day + vitamin C. IV if intolerant/CKD/severe. Always find the source.
Pearl
Reticulocyte count is the most underordered test. Ferritin is an acute phase reactant. Smear is free and diagnostic.
📄 One Pager
One-Pager
Anemia Workup
MCV → Retic → Smear
Algorithm
Step 1: CBC + retic + smear. Step 2: MCV-based labs (micro → iron studies; normo → hemolysis labs + CKD; macro → B12/folate). Step 3: Bone marrow if unexplained.
Iron Studies Cheat Sheet
IDA: ferritin ↓, TIBC ↑, TfSat ↓. ACD: ferritin ↑, TIBC ↓, TfSat low-normal. IDA+ACD: ferritin 30-100, check sTfR. Hemolysis: LDH ↑, haptoglobin ↓, retic ↑, DAT±.
Trials
TRICC 1999 (restrictive transfusion) · IRON-MIDE 2020 (every-other-day iron) · TREAT 2009 (EPO in CKD)
Hematology
Hemolytic Anemia
Accelerated RBC destruction. Coombs test is the branch point: positive = immune (autoimmune, drug, transfusion). Negative = non-immune (mechanical, intrinsic RBC defect). Always check the smear.
🔍 Overview
Overview
Hemolytic anemia = shortened RBC lifespan (< 120 days) causing anemia with compensatory reticulocytosis. Hallmark labs: elevated LDH, elevated indirect bilirubin, low/undetectable haptoglobin, elevated reticulocyte count. Two categories by mechanism: Intravascular hemolysis (RBCs destroyed in circulation -hemoglobinuria, hemoglobinemia, very low haptoglobin -PNH, TTP, mechanical valve, transfusion reaction, DIC). Extravascular hemolysis (RBCs destroyed by splenic macrophages -splenomegaly, jaundice, no hemoglobinuria -AIHA, hereditary spherocytosis, sickle cell, hypersplenism). The direct Coombs test (DAT) is the critical branch point: positive = antibody on RBCs → immune hemolysis. Negative = non-immune → check smear for mechanistic clues.
🧪 Workup
Workup
- Hemolysis labs: LDH (↑), haptoglobin (↓ or undetectable), indirect bilirubin (↑), reticulocyte count (↑). All four should be checked together.
- Direct Coombs test (DAT) -the branch point.
- DAT positive: warm AIHA (IgG -most common, responds to steroids), cold agglutinin disease (IgM + complement -associated with Mycoplasma, lymphoma), drug-induced (cephalosporins, piperacillin, methyldopa), transfusion reaction
- DAT negative: microangiopathic (TTP, DIC, HUS -schistocytes on smear), mechanical (prosthetic valve), PNH (flow cytometry for GPI-anchored proteins), intrinsic RBC defects (G6PD, hereditary spherocytosis, sickle cell, thalassemia). If TTP suspected → calculate PLASMIC score (predicts ADAMTS13 deficiency) PLASMIC Score, Bendapudi 2017
- Peripheral smear -essential. Schistocytes (TMA), spherocytes (AIHA, HS), sickle cells, bite cells (G6PD), target cells (thalassemia, liver)
- 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
- PNH: Eculizumab (anti-C5 complement inhibitor) TRIUMPH, 2006. Meningococcal vaccine required before starting. Ravulizumab (longer-acting) available.
- G6PD: Remove trigger (stop offending drug, treat infection). Supportive care. Avoid oxidant drugs lifelong.
- Mechanical valve hemolysis: Usually mild. If severe → evaluate for paravalvular leak (echo). Iron/folate supplementation for chronic hemolysis.
💊 Medications
Medications
| Drug | Dose | Route | Notes |
|---|---|---|---|
| Prednisone | 1 mg/kg daily → taper | PO | First-line for warm AIHA. 70-85% respond. Taper slowly (relapse if too fast). Chronic steroid toxicity limits duration. |
| Rituximab | 375 mg/m² weekly × 4 | IV | Second-line for warm AIHA, first-line for CAD. Anti-CD20. Screen HBV. Response in 1-3 weeks. |
| Eculizumab | 600 mg IV q7d × 4 → 900 mg q14d | IV | PNH -anti-C5 complement inhibitor. Meningococcal vaccine ≥ 2 weeks before. Lifelong therapy. TRIUMPH, 2006 |
Monitoring
🏥 Rounds
Pimp Questions
❓ 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")
- Folic acid 1 mg daily (hemolysis depletes folate stores)
- 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
- Avoid oxidant triggers: sulfonamides, dapsone, nitrofurantoin, primaquine, fava beans, mothballs (naphthalene)
- 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)
- On eculizumab/ravulizumab: meningococcal vaccination status, breakthrough hemolysis (LDH spike), Cr, CBC
- Cold agglutinin: titer levels, avoid cold triggers, monitor for worsening during winter
- Folate level -chronic hemolysis depletes folate → megaloblastic crisis if not supplemented
Monitoring
📋 Summary
Summary
Hemolysis Labs
LDH ↑, haptoglobin ↓, indirect bili ↑, reticulocyte ↑. Check all four.
DAT Positive
Warm AIHA (IgG → steroids), cold agglutinin (C3d → keep warm + rituximab), drug-induced, transfusion reaction
DAT Negative
TTP/DIC (schistocytes), PNH (flow cytometry), G6PD (bite cells), mechanical valve, hereditary spherocytosis
Warm AIHA Rx
Prednisone 1 mg/kg → rituximab → splenectomy. DO transfuse if life-threatening (least incompatible).
PNH
Eculizumab (anti-C5). Meningococcal vaccine first. Lifelong therapy.
Pearl
Haptoglobin = most sensitive marker. G6PD level falsely normal during hemolysis. Always check the smear.
📄 One Pager
One-Pager
Hemolytic Anemia
DAT is the branch point
Algorithm
Confirm hemolysis (LDH ↑ + haptoglobin ↓ + retic ↑ + indirect bili ↑) → DAT. Positive: warm AIHA vs cold vs drug. Negative: check smear -schistocytes (TMA), spherocytes (HS), bite cells (G6PD). PNH: flow cytometry.
Smear Clues
Schistocytes → TTP/DIC/valve. Spherocytes → AIHA or HS. Bite cells/Heinz bodies → G6PD. Sickle cells → SCD. Target cells → thalassemia/liver.
Trials
TRIUMPH 2006 (eculizumab for PNH) · CARDINAL 2022 (sutimlimab for CAD)
Stay Current
📰 What's New
Practice-changing updates in internal medicine. Each entry links to the relevant topic on this site. Bookmark this page and check back regularly.
🔥 2026 Updates
March 2026 · JUST RELEASED
Surviving Sepsis Campaign 2026 -Adult & Pediatric Guidelines
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, then vasopressin, then epinephrine. MAP target 65 mmHg (higher targets showed no mortality benefit). New guidance on BP targets in older adults.
Corticosteroids: IV hydrocortisone 200 mg/day suggested for septic shock with ongoing vasopressor requirement ≥ 4 hours. Shortens shock duration but unclear mortality benefit. This reverses the 2016 recommendation against routine steroids.
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.
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, then vasopressin, then epinephrine. MAP target 65 mmHg (higher targets showed no mortality benefit). New guidance on BP targets in older adults.
Corticosteroids: IV hydrocortisone 200 mg/day suggested for septic shock with ongoing vasopressor requirement ≥ 4 hours. Shortens shock duration but unclear mortality benefit. This reverses the 2016 recommendation against routine steroids.
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.
🔥 2024–2025 Updates
2025
2025 AHA/ACC Acute Coronary Syndromes Guidelines
First unified ACS guideline combining STEMI and NSTEMI into a single framework. Key changes: high-sensitivity troponin now standard for diagnosis with 0/1-hour or 0/2-hour rapid rule-out algorithms. Clopidogrel now preferred over ticagrelor as default P2Y12 inhibitor (based on cost-effectiveness and bleeding data). Pre-treatment with P2Y12 inhibitors before angiography is no longer recommended for NSTEMI. De-escalation from potent P2Y12 to clopidogrel after 1–3 months is endorsed. DAPT duration shortened to 1–3 months followed by P2Y12 monotherapy for high bleeding risk. Routine pre-hospital ECG and direct-to-cath-lab activation reaffirmed for STEMI. Colchicine considered for secondary prevention (post-MI anti-inflammatory). Prasugrel preferred over ticagrelor when PCI is planned and anatomy is known. → STEMI Topic • → NSTEMI Topic
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
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
📋 2022–2023 Practice Changes
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
2023
SELECT Trial: Semaglutide Reduces Cardiovascular Events
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
📚 How to Stay Updated
| Source | What It Is | Cost |
|---|---|---|
| NEJM Journal Watch | Daily summaries of practice-changing studies across all journals | Often free through residency programs |
| The Curbsiders | Internal medicine podcast -deep dives with experts | Free |
| Core IM | Podcast + 5-Pearls -concise clinical pearls | Free |
| REBEL EM / EMCrit | Critical care & EM focused evidence updates | Free |
| UpToDate "What's New" | Real-time guideline updates with practice recommendations | Institutional access |
| Society Guidelines | AHA/ACC, ATS/IDSA, KDIGO, SSC -subscribe to email alerts | Free |
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
Full Comparison Table
| Domain | Surviving Sepsis Campaign 2021 | Surviving Sepsis Campaign 2026 | Impact |
|---|---|---|---|
| Screening | qSOFA suggested as bedside screen outside ICU. Score ≥ 2 triggers SOFA assessment. | 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. Strong recommendation. | 30 mL/kg still suggested but downgraded emphasis -greater focus on individualization and dynamic reassessment after each bolus. 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. Vasopressin or epinephrine as second-line. Against dopamine as alternative. | Unchanged: NE first-line → vasopressin → epinephrine. Dopamine remains discouraged (more arrhythmias per SOAP II). Against use of angiotensin II, terlipressin, or selepressin. | No change |
| MAP Target | MAP ≥ 65 mmHg. Higher targets (80+) showed no benefit. | MAP ≥ 65 mmHg unchanged. New: BP targets for older adults now specifically addressed (previously one-size-fits-all). | Moderate |
| Corticosteroids | Suggested if ongoing vasopressor requirement. No clear time threshold specified. | Hydrocortisone 200 mg/day (50 mg q6h) if vasopressors ≥ 4 hours. Clear time trigger. Shortens shock duration. Reverses 2016 recommendation against routine use. ADRENAL 2018 + APROCCHSS 2018 support this. | Major |
| 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 |
| Lactate | Measure lactate. Remeasure if initial > 2 mmol/L. Guide resuscitation to normalize lactate. | Unchanged. Lactate-guided resuscitation remains recommended. Serial monitoring to assess clearance. | No change |
| Albumin | Suggested as supplement to crystalloids for patients receiving large volumes. | Albumin NOT recommended as supplement to crystalloids for initial resuscitation. | Moderate |
| Code Sepsis | Not addressed. | New: "Code sepsis" huddle protocols suggested. Structured multidisciplinary response to sepsis recognition, similar to code blue or stroke codes. | New |
| Institutional QI | Performance improvement mentioned. | Institutional performance improvement programs now formally recommended. Sepsis education, bundle compliance monitoring, outcome tracking. | Moderate |
| Post-Discharge | Not addressed. | 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 earlier (4h), 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 6 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 → vasopressin → epi order unchanged. New: BP targets for older adults now addressed.
4. Earlier Steroids
Hydrocortisone 200 mg/day if vasopressors ≥ 4 hours. Shortens shock duration. Reverses the 2016 recommendation against routine steroids. Don't wait all day -4 hours is the trigger.
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.
📊 By the Numbers
129
Total Statements
46
New Recommendations
68
Expert Panel (Pediatric)
5
Years Since Last Update
Full Clinical Protocol: Sepsis & Septic Shock Topic → |
External: Full Adult Guidelines (CCM) →
🆕 Entirely New in 2026
46 New Statements -Key Highlights
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.
🧓 Older Adult BP Targets
BP targets for older adults with septic shock are now specifically addressed. Previous guidelines used a one-size-fits-all MAP ≥ 65 mmHg. The 2026 guidelines acknowledge that older adults may benefit from individualized targets, recognizing that aggressive MAP targets can increase vasopressor exposure and complications.
🏥 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.
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 | NE had lower mortality and fewer arrhythmias vs dopamine | NE remains first-line vasopressor |
| 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 | Supports steroid use for shock reversal |
Full Clinical Protocol: Sepsis & Septic Shock Topic → |
External: Full Adult Guidelines (CCM) → |
SCCM Official Page →
URGENTNephrology
Rhabdomyolysis
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
- Medications -statins (especially + fibrates or CYP3A4 inhibitors), daptomycin, colchicine, antipsychotics (NMS)
- Seizures -prolonged/status epilepticus
- Extreme exertion -marathon, military training, CrossFit (especially in heat)
- NMS / Serotonin syndrome -see NMS vs Serotonin Syndrome
- Heat stroke -see Heat Stroke
- Metabolic -hypokalemia, hypophosphatemia, hypothyroidism, DKA
- 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. |
| 2. Treat hyperkalemia | Calcium gluconate, insulin + D50, kayexalate/patiromer | 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.
- BMP -K⁺ (hyperK!), Ca²⁺ (hypoCa), PO₄ (hyperPhos), Cr/BUN (AKI), bicarb (metabolic acidosis)
- 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.
- Toxicology screen -if etiology unclear (cocaine, amphetamines)
- ECG -hyperkalemia changes (peaked T-waves, wide QRS)
💊 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. |
| Urine pH | q6h if giving bicarb | Target > 6.5 if alkalinizing urine. |
| Compartment checks | q2–4h if limb involved | Tense, painful, swollen limb → measure pressures → fasciotomy if > 30 mmHg. |
| Vitals | q4h floor, q1–2h ICU | Watch for fluid overload with aggressive resuscitation. |
📋 On Rounds
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.
Key findings: CK 22,000. Cr 2.8 (baseline 1.6). K+ 5.4. Phosphorus 6.1. Simvastatin + clarithromycin = CYP3A4 drug interaction causing toxic statin levels.
Management:
- Stop simvastatin AND clarithromycin immediately
- 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.
Key findings: Compartment pressure measurement: 38 mmHg (normal < 10). Delta pressure (diastolic BP - compartment pressure) = 22 mmHg (< 30 = concerning). Classic 5 P's: pain out of proportion, pain with passive stretch, pressure, paresthesias (late), pulselessness (very late).
Management:
- Emergent fasciotomy — this is a surgical emergency
- 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
Diagnosis
CK > 5× ULN (typically > 5,000). UA: dipstick + blood, no RBCs on micro = myoglobinuria. Dark brown "tea-colored" urine.
Treatment
Aggressive IVF (NS/LR 200–300 mL/hr) targeting UOP 200–300 mL/hr. Bicarb for urine alkalinization is controversial.
Three Killers
Hyperkalemia (check K⁺ q4–6h), AKI (myoglobin tubular necrosis), Compartment syndrome (check pressures if limb involved).
Calcium Rule
Do NOT give calcium for asymptomatic hypocalcemia -deposits in damaged muscle. Only give for hyperK with ECG changes or symptomatic tetany.
Common Causes
Crush injury, immobilization ("found down"), drugs of abuse, statins, seizures, extreme exertion, NMS, heat stroke.
Dialysis
Indicated for refractory hyperK, severe acidosis, volume overload, uremia. CRRT preferred. Standard HD does not clear myoglobin.
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). | SSRIs, SNRIs, MAOIs, tramadol, linezolid (weak MAOI!), fentanyl, ondansetron, triptans, St. John's Wort, MDMA, dextromethorphan |
| Onset | SLOW -days to weeks after starting/increasing dose | FAST -hours after starting, dose change, or drug interaction |
| Key finding | LEAD-PIPE RIGIDITY (diffuse, not clonus) | CLONUS (especially lower extremity) + hyperreflexia |
| Temperature | Very high (> 40°C common) | Variable (mild to very high) |
| Mental status | Altered (encephalopathy, obtundation) | Agitation, confusion, restlessness |
| Autonomic | Tachycardia, labile BP, diaphoresis | Tachycardia, hypertension, diaphoresis, mydriasis |
| GI symptoms | Usually absent | Diarrhea (serotonin stimulates gut motility) |
| Labs | CK markedly elevated (often > 1,000), leukocytosis, metabolic acidosis | CK may be mildly elevated, otherwise normal |
| Treatment | STOP offending agent, dantrolene + bromocriptine, cooling, ICU | STOP offending agent, benzodiazepines (first-line), cyproheptadine, cooling |
| Duration | Days to weeks to resolve | Usually resolves within 24 hours of stopping drug |
NMS -Neuroleptic Malignant Syndrome
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.
Key findings: CK 18,400, WBC 16K, Cr 2.8 (baseline 0.9). Diaphoretic, mute, tremulous. Recently started high-potency antipsychotic. Classic NMS: fever + rigidity + AMS + autonomic instability.
Management:
- Stop haloperidol immediately
- Dantrolene 1-2.5 mg/kg IV q6h (skeletal muscle relaxant — reduces rigidity and thermogenesis)
- Bromocriptine 2.5 mg PO/NG TID (dopamine agonist — reverses central dopamine blockade)
- Aggressive IVF (NS 200 mL/hr) for rhabdomyolysis — target UOP > 200 mL/hr
- 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)
- Cyproheptadine 12 mg PO load → 4 mg q6h (serotonin antagonist — first-line antidote)
- 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.
Management:
- Stop both quetiapine and duloxetine
- Key distinguisher: clonus + hyperreflexia → favors serotonin syndrome over NMS
- 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. |
| BMP (K⁺, Cr) | q6–12h | Watch for hyperK (NMS) and AKI. |
| Neurological exam | q2–4h | Rigidity assessment (NMS), clonus assessment (SS), mental status. |
| Vitals | q1–2h ICU | HR, BP (labile in both), SpO₂, RR. |
| Coags | Daily if NMS severe | DIC screening (PT, fibrinogen, D-dimer). |
⚡ Summary
NMS vs Serotonin Syndrome -Key Points
NMS Cause
Dopamine ANTAGONISTS: haloperidol, olanzapine, metoclopramide. Also levodopa withdrawal. Onset: days–weeks.
SS Cause
Serotonergic drugs: SSRIs, SNRIs, MAOIs, tramadol, linezolid, MDMA. Usually drug interaction. Onset: hours.
Key Finding
NMS = RIGIDITY (lead-pipe). SS = CLONUS (hyperreflexia, especially lower extremity). This is the #1 distinguishing feature.
NMS Treatment
Stop drug. Dantrolene 1–2.5 mg/kg IV. Bromocriptine 2.5 mg PO q8h (continue 10 days). Cooling. ICU.
SS Treatment
Stop drug. Benzodiazepines (first-line). Cyproheptadine 12 mg load then 2 mg q2h. Cooling. Usually resolves in 24h.
Pearl
Linezolid is a weak MAOI → can cause SS with SSRIs. Do NOT give dantrolene for SS. Do NOT give cyproheptadine for NMS.
URGENTHeme/Onc
Hypercalcemia of Malignancy
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.
🔍 Overview
Mechanisms of Malignancy-Related Hypercalcemia
| Mechanism | Frequency | Associated Cancers | Key Lab Finding |
|---|---|---|---|
| PTHrP (Humoral) | ~80% | Squamous cell carcinomas (lung, H&N), renal cell, breast, bladder | PTHrP elevated, PTH suppressed, PO₄ low |
| Osteolytic metastases | ~20% | Breast cancer, multiple myeloma | PTHrP normal, local cytokine release (RANKL, IL-6) |
| 1,25-dihydroxyvitamin D | < 1% | Lymphoma (Hodgkin and non-Hodgkin) | 1,25-vit D elevated (tumor-produced 1-alpha hydroxylase) |
| Ectopic PTH | Very rare | Ovarian, lung small cell (rare) | PTH elevated (from tumor) |
Symptoms -"Stones, Bones, Groans, Psychiatric Moans"
- Stones: Nephrolithiasis, nephrocalcinosis, polyuria (nephrogenic DI from Ca²⁺ → impaired ADH response)
- Bones: Bone pain, pathologic fractures, osteoporosis
- Groans: Abdominal pain, constipation, nausea, vomiting, pancreatitis (rare)
- Psychiatric moans: Confusion, lethargy, depression, psychosis, coma
- Cardiac: Shortened QT interval, bradycardia, AV block (severe)
- Renal: Polyuria → dehydration → worsening hypercalcemia (vicious cycle)
Severity Classification
| Severity | Corrected Ca²⁺ | Approach |
|---|---|---|
| Mild | 10.5–12.0 mg/dL | Oral hydration, monitor, treat underlying malignancy |
| Moderate | 12.0–14.0 mg/dL | IV fluids ± calcitonin + bisphosphonate |
| Severe / Symptomatic | > 14.0 mg/dL or symptomatic | 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. (2)
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 -Hypertrophic Cardiomyopathy
| 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
Mechanisms
PTHrP (80% -squamous, renal, breast), osteolytic mets (20% -breast, myeloma), 1,25-vit D (<1% -lymphoma).
Key Lab
PTH SUPPRESSED (unlike primary hyperparathyroidism). PTHrP elevated. Corrected Ca or ionized Ca. Shortened QT on ECG.
Step 1
Aggressive IV NS 200–300 mL/hr. Most patients are severely volume-depleted. Drops Ca 1–2 mg/dL alone.
Step 2
Calcitonin 4 IU/kg SQ q12h -works in HOURS but tachyphylaxis by 48h. Bridge therapy only.
Step 3
Zoledronic acid 4 mg IV -definitive treatment. Takes 2–4 DAYS. Lasts weeks. Check Cr first.
Outdated
Furosemide for hypercalcemia is OUTDATED. Only use if volume overloaded. Does not meaningfully lower calcium.
WardsSurgery Co-management
Perioperative Medicine
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.
💊 Medications
Perioperative Medication Management
| Drug Class | Action | Rationale |
|---|---|---|
| Beta-blockers | CONTINUE (do NOT start new) | Withdrawal → rebound tachycardia/ischemia. POISE trial: starting new BB → ↑ stroke + death. |
| Statins | CONTINUE | Pleiotropic anti-inflammatory effects reduce periop cardiac events. |
| ACEi/ARBs | HOLD morning of surgery | 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. |
RoundsRx Licensed Content - Unauthorized Use Prohibited📋 On Rounds
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. |
| Glucose | q6h if diabetic (AC + HS) | Target 140–180 mg/dL inpatient. Avoid hypoglycemia. Sliding scale + reduced basal. |
| DVT prophylaxis | Assess daily | SQ heparin 5,000 units q8h or enoxaparin 40 mg SQ daily. SCDs if anticoag contraindicated. |
| I&Os | Strict if major surgery | UOP ≥ 0.5 mL/kg/hr. Monitor for fluid overload or hypovolemia. |
| Pain management | Each assessment | Multimodal: acetaminophen + NSAIDs (if no contraindication) + opioids PRN. Minimize opioids. |
| Incentive spirometry | q1h while awake | 10 breaths q1h. Prevents atelectasis and postop pneumonia. |
⚡ Summary
Perioperative Medicine -Key Points
Cardiac Risk
RCRI: 6 predictors. ≥4 METs = low risk regardless. Stress test only if poor functional capacity + elevated RCRI + will change management.
Beta-blockers
CONTINUE if on them. NEVER start new within 24h of surgery (POISE -↑ stroke + death). Withdrawal is also dangerous.
Anticoagulation
Warfarin: stop 5 days. Bridge ONLY for mechanical mitral valve, VTE <3mo, very high CHA₂DS₂-VASc. BRIDGE trial: most AF patients do NOT need bridging.
Diabetes
Hold metformin day of surgery. Hold SGLT2i 3–4 days before (euglycemic DKA). Reduce basal insulin to 50–80%. Hold orals AM of surgery.
Pulmonary
Routine preop PFTs NOT recommended. Incentive spirometry, smoking cessation ≥8wk, early postop mobilization. No routine CXR.
SGLT2i Pearl
Hold empagliflozin/dapagliflozin 3–4 days preop. Risk of euglycemic DKA -normal glucose but elevated ketones + anion gap acidosis.
Pulm/Rheum
Sarcoidosis
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.
Indications for Treatment
- Progressive pulmonary disease -worsening PFTs, increasing infiltrates
- Cardiac involvement -heart block, cardiomyopathy, ventricular arrhythmias
- Neurological involvement -cranial nerve palsies, CNS mass lesions, seizures
- Hypercalcemia -from granulomatous production of 1,25-dihydroxyvitamin D
- Disfiguring skin disease -lupus pernio
- Significant eye disease -posterior uveitis, optic neuritis refractory to topical therapy
- Renal involvement -nephrocalcinosis, nephrolithiasis from hypercalciuria
First-Line Therapy
Prednisone 20-40 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
- CBC, BMP, LFTs -baseline; elevated alk phos suggests hepatic granulomas
- 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 |
| Azathioprine (Imuran) | 50-200 mg daily | PO | Check TPMT before starting (homozygous deficiency = fatal myelosuppression). Monitor CBC regularly. |
| Mycophenolate (CellCept) | 500-1500 mg BID | PO | 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.
Key findings: CXR: bilateral hilar LAD + reticular opacities (Stage II). PFTs: FVC 65%, DLCO 58%. Calcium 11.2. Ophthalmology: anterior uveitis. Biopsy: non-caseating granulomas, AFB/fungal negative.
Management:
- Prednisone 40 mg daily × 4-6 weeks, then taper over 6-12 months
- Topical steroids for uveitis (ophthalmology comanagement)
- Methotrexate as steroid-sparing agent for prolonged therapy
- ECG screening for cardiac sarcoidosis
Teaching point: Not all sarcoidosis needs treatment. Indications: progressive pulmonary disease, hypercalcemia, cardiac involvement, neurosarcoidosis, sight-threatening uveitis.
📋 Case 2 — Lofgren Syndrome
Patient: 28-year-old Scandinavian woman with acute bilateral ankle pain, fever, and tender erythematous shin nodules × 1 week.
Key findings: CXR: bilateral hilar LAD (Stage I). Classic triad: BHL + erythema nodosum + polyarthralgia. ESR elevated. Calcium normal.
Management:
- 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
Pathology
Non-caseating granulomas. Must exclude TB, fungal, lymphoma.
Classic CXR
Bilateral hilar lymphadenopathy. Scadding staging I-IV.
Treatment
Many DON'T need treatment. First-line: prednisone 20-40 mg. Steroid-sparing: MTX, AZA.
ACE Level
NOT diagnostic. Sensitivity 60%, specificity poor. Biopsy is required.
Lofgren
BHL + erythema nodosum + polyarthralgia + fever. Excellent prognosis. Biopsy often NOT needed.
Hypercalcemia
Granulomatous 1,25-vit D production. PTH suppressed. Treat with steroids.
GI
Autoimmune Hepatitis
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.
Management:
- Restart prednisone 30-40 mg daily (re-induce remission)
- 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).
- Hepatocellular carcinoma screening -if cirrhosis present, standard HCC screening (ultrasound + AFP q6 months).
- Bone density -DEXA if prolonged steroid use.
📋 Summary
Summary
Hallmark
Elevated IgG + autoantibodies (ANA, ASMA, anti-LKM1) + interface hepatitis on biopsy
Types
Type 1: ANA/ASMA+ (80%, adults). Type 2: anti-LKM1+ (children, more severe).
Treatment
Prednisone 40-60 mg + azathioprine 1-2 mg/kg. Check TPMT first!
Maintenance
Azathioprine monotherapy. Lifelong in most. 80-90% relapse if stopped.
Budesonide
Alternative to prednisone. Do NOT use in cirrhosis (portosystemic shunts).
Danger
TPMT deficiency + azathioprine = fatal myelosuppression. Always test first.
GI
PBC / PSC
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 |
| Symptoms | Pruritus, fatigue | Pruritus, jaundice, RUQ pain, cholangitis episodes |
| Associated Conditions | Sjogren, thyroiditis, celiac, RA | Ulcerative colitis (70%), cholangiocarcinoma |
| Cancer Risk | Hepatocellular carcinoma (if cirrhosis) | Cholangiocarcinoma (lifetime risk 10-15%), gallbladder cancer, colon cancer (if UC) |
| Treatment | Ursodiol (UDCA) works | NO proven medical therapy |
🚨 Management
PBC Management
- First-line: Ursodiol (UDCA) 13-15 mg/kg/day (split BID). Improves LFTs, delays histologic progression, improves transplant-free survival. Poupon, NEJM 1991
- Incomplete response to UDCA: Obeticholic acid (Ocaliva) -FXR agonist. Add if ALP >1.67x ULN or bilirubin elevated after 12 months of UDCA. Caution: worsens pruritus significantly. Contraindicated in decompensated cirrhosis (FDA black box). 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. |
| Obeticholic Acid (Ocaliva) | PBC (UDCA-incomplete) | 5 mg daily, may increase to 10 mg | FXR agonist. Worsens pruritus. Black box: contraindicated in decompensated cirrhosis. 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.
Management:
- Ursodiol (UDCA) 13-15 mg/kg/day in divided doses (first-line — slows disease progression)
- Assess response at 1 year: ALP < 1.67× ULN = adequate response (Paris criteria)
- If inadequate response: add obeticholic acid (FXR agonist) POISE, 2016
- 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
PBC Key
AMA+, middle-aged women, pruritus. Ursodiol 13-15 mg/kg WORKS.
PSC Key
Beading on MRCP, young men, 70% have UC. NO proven medical therapy.
PSC Cancer
Cholangiocarcinoma risk 10-15%. Screen CA 19-9 + MRCP annually.
UDCA in PSC
Does NOT improve survival. High-dose was HARMFUL. Common but unproven use.
PBC Incomplete
Obeticholic acid (Ocaliva) if ALP >1.67x after 12 months UDCA. Worsens pruritus.
Definitive Tx
Liver transplant for both if decompensated. PSC recurs ~20% post-transplant.
URGENTNeuro
PRES
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
- Chemotherapy -especially VEGF inhibitors (bevacizumab)
- Autoimmune disease -SLE, TTP, thrombotic microangiopathy
- 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)
- Eclampsia: magnesium sulfate + delivery
- Drug-induced: discontinue offending agent (tacrolimus, cyclosporine, chemotherapy)
- 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.
- Neurologic exam -serial neuro checks q1-2h. Document mental status, vision, motor function.
- 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
Triad
Seizures + headache + visual changes with hypertension. Posterior white matter edema on MRI.
Causes
Severe HTN, eclampsia, tacrolimus/cyclosporine, chemotherapy, autoimmune disease.
Diagnosis
MRI with FLAIR. T2/FLAIR bright in posterior regions. DWI normal (vasogenic, not cytotoxic).
Treatment
Treat the CAUSE. Lower BP. Remove offending drug. Seizure control (levetiracetam).
Prognosis
Usually REVERSIBLE if treated promptly. Delayed Tx = infarction, hemorrhage, death.
Misnomer
Not always posterior. Not always reversible. CT can miss it -MRI is essential.
Heme/Onc
Amyloidosis
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.
- Kidney -nephrotic syndrome (proteinuria, edema, hypoalbuminemia)
- Liver -hepatomegaly, elevated ALP
- Nerves -peripheral neuropathy (pain, numbness), autonomic neuropathy (orthostatic hypotension)
- GI -malabsorption, weight loss, GI bleeding
- 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.
- First-line: Daratumumab + CyBorD (cyclophosphamide, bortezomib, dexamethasone). ANDROMEDA, NEJM 2021 -showed significantly higher hematologic complete response rate.
- 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
- Dara-CyBorD: daratumumab + bortezomib + cyclophosphamide + dexamethasone (first-line per ANDROMEDA) ANDROMEDA, 2021
- 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.
Management:
- Tafamidis 80 mg daily — TTR stabilizer, reduces mortality and HF hospitalization ATTR-ACT, 2018
- 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.
Management:
- Cardiac biomarkers: NT-proBNP + troponin (Mayo staging — determines prognosis and treatment intensity)
- 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.
- Echocardiogram -q6-12 months. Monitor wall thickness, diastolic function, strain patterns.
- ALP -for hepatic involvement. Hepatic response: >50% decrease in ALP.
- Orthostatic vitals -for autonomic neuropathy monitoring.
- CBC, BMP -monitor for treatment toxicity (myelosuppression from chemo, renal function).
📋 Summary
Summary
Diagnosis
Congo red stain: apple-green birefringence. Fat pad aspirate is least invasive.
Classic Clue
Low voltage ECG + thick walls echo = amyloid (HCM = thick walls + HIGH voltage).
AL Treatment
Dara-CyBorD (ANDROMEDA). Auto-SCT if eligible. Cardiac = poor prognosis.
AA Treatment
Treat underlying inflammation (RA, Crohn, FMF). Reduce SAA levels.
Avoid
Digoxin (binds amyloid = toxicity). Aggressive diuresis (preload-dependent).
Pathognomonic
Macroglossia = AL amyloidosis. Does not occur in AA or ATTR.
EMERGENTICU
Fat Embolism Syndrome
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
- Liposuction
- Burns, pancreatitis, sickle cell fat marrow necrosis (rare causes)
Pathophysiology
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.
🚨 Management
Treatment
SUPPORTIVE -there is no specific treatment for fat embolism syndrome.
- Supplemental oxygen -high-flow nasal cannula, NIPPV, or mechanical ventilation as needed
- Mechanical ventilation -lung-protective ventilation if ARDS develops (low tidal volume 6 mL/kg IBW, PEEP, plateau pressure <30 cmH2O)
- Fluid resuscitation -maintain intravascular volume. Avoid hypovolemia (worsens tissue hypoperfusion).
- 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.
- CBC -thrombocytopenia (platelet consumption), anemia (from hemolysis by free fatty acids)
- Lipase -may be elevated (fat hydrolysis)
- CT-PA -primarily to rule out pulmonary embolism (PE and FES can both occur after fractures/surgery). FES does NOT show filling defects.
- Retinal exam -cotton-wool spots, petechiae, fat emboli visible in retinal vessels (Purtscher-like retinopathy)
- 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:
- Major: Axillary/subconjunctival petechiae, hypoxemia (PaO2 <60), CNS depression, pulmonary edema
- Minor: Tachycardia, fever, retinal changes, fat in urine, thrombocytopenia, elevated ESR, fat globules in sputum
💊 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
Classic Triad
Hypoxemia + AMS + petechial rash, 24-72h after long bone fracture.
Diagnosis
Clinical diagnosis. No definitive test. CT-PA to rule out PE. Gurd criteria.
Treatment
SUPPORTIVE. O2, ventilation (lung-protective if ARDS), fluids, early fracture fixation.
Rash
Petechiae on chest/axillae/conjunctivae. Most specific finding but only ~50% of cases.
Prevention
Early fracture fixation. ?Methylprednisolone prophylaxis in high-risk cases.
Prognosis
Most cases self-resolve with supportive care. Mortality ~5-15% in severe cases (ARDS).
EMERGENTICU
Malignant Hyperthermia
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.
Triggers
- Volatile anesthetics: sevoflurane, desflurane, isoflurane, halothane (most potent trigger)
- Succinylcholine (depolarizing neuromuscular blocker)
- NOT triggered by: non-depolarizing agents (rocuronium, vecuronium), propofol, benzodiazepines, nitrous oxide, opioids, stress alone, exercise alone
Pathophysiology
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.
Presentation
- Earliest sign: Rising ETCO2 (unexpectedly, often >60 mmHg despite adequate ventilation)
- 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.
- Coagulation panel — PT, PTT, fibrinogen, D-dimer (DIC screen)
- Lactate — markedly elevated (hypermetabolic state)
- 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.
- BMP q4-6h — potassium, calcium, creatinine trending.
- Coags q6-12h — DIC surveillance (falling fibrinogen, rising D-dimer, dropping platelets).
- 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
Trigger
Volatile anesthetics (sevoflurane, desflurane, isoflurane) and succinylcholine. RYR1 mutation.
Earliest Sign
Rising ETCO2 despite adequate ventilation. Temperature rise is a LATE sign.
Treatment
STOP trigger + Dantrolene 2.5 mg/kg IV push q5min. No max dose. Active cooling. Treat hyperK.
Key Pearl
Each dantrolene vial = 20 mg. A 70 kg patient needs ~9 vials for first dose. Call for help early.
Avoid
Calcium channel blockers (fatal interaction with dantrolene). Use amiodarone for arrhythmias.
Recrudescence
25% recurrence within 24-36h. Continue dantrolene 1 mg/kg q6h x 24-48h. ICU monitoring.
EMERGENTGI/ICU
Acute Liver Failure
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 (paracetamol) — #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
- Budd-Chiari syndrome — hepatic vein thrombosis
- Drug-induced — isoniazid, phenytoin, statins, herbal supplements, anti-TB drugs
- Pregnancy-related — HELLP syndrome, acute fatty liver of pregnancy (AFLP)
- Ischemic hepatitis — "shock liver" from hypoperfusion
- Mushroom poisoning — Amanita phalloides (death cap)
- 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)
- Autoimmune: ANA, anti-smooth muscle antibody (ASMA), IgG levels
- Wilson disease: Ceruloplasmin (low), 24h urine copper, slit-lamp exam (Kayser-Fleischer rings). Alkaline phosphatase:bilirubin ratio <4 + AST:ALT ratio >2.2 suggests Wilson.
- Budd-Chiari: Doppler ultrasound of hepatic veins
- Pregnancy test — HELLP, AFLP
- Drug screen / toxicology — urine drug screen, medication reconciliation
- HSV — HSV PCR if immunocompromised or unexplained (consider empiric acyclovir)
Baseline Labs
- CBC, CMP (LFTs, BMP), coags (INR, PT, fibrinogen), lactate, ammonia level, lipase
- ABG (acid-base status), phosphate (prognostic — rising phosphate in acetaminophen ALF = failure to regenerate)
- Blood type and screen (anticipate possible transplant)
💊 Medications
Medications
| Drug | Indication | Dose | Notes |
|---|---|---|---|
| N-acetylcysteine (NAC) | ALL ALF — first-line | 150 mg/kg IV over 1h → 50 mg/kg over 4h → 100 mg/kg over 16h | Continue until INR <1.5 or transplant. Improves transplant-free survival even in NON-acetaminophen ALF. Lee, Gastroenterology 2009 |
| Mannitol 20% | Cerebral edema / herniation | 0.5-1 g/kg IV bolus | Use if serum osm <320. Can repeat x1. Monitor serum osmolality. |
| Hypertonic saline (3% or 23.4%) | Cerebral edema prophylaxis | 3% NaCl infusion targeting Na 145-155 | Prophylactic hypernatremia reduces cerebral edema incidence. 23.4% (30 mL) for acute herniation. |
| Dextrose 10% (D10) | Hypoglycemia prevention | Continuous drip at 75-100 mL/h | 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
Definition
INR ≥1.5 + encephalopathy + no prior liver disease + <26 weeks.
#1 Cause
Acetaminophen (US/UK). Best prognosis. Often unintentional supratherapeutic dosing.
First-Line
NAC for ALL ALF (not just acetaminophen). 150/50/100 mg/kg IV protocol.
Do NOT
Correct INR prophylactically. It is your prognostic marker. Only give FFP if actively bleeding.
Transplant
Apply King's College Criteria serially. Contact transplant center EARLY.
Complications
Cerebral edema, hypoglycemia (D10 drip), coagulopathy, infection (80%), AKI (50-70%).
Nephrology
Renal Transplant Medicine
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
Immunosuppression
Standard regimen has three components:
- Induction: Basiliximab (IL-2 receptor antagonist, low immunologic risk) or Anti-thymocyte globulin (ATG) (high immunologic risk, repeat transplant, sensitized patients)
- Maintenance (triple therapy):
- Tacrolimus (Prograf) — calcineurin inhibitor. Target trough varies by time post-transplant: 8-12 ng/mL (month 0-3), 6-10 ng/mL (month 3-12), 4-8 ng/mL (after year 1).
- Mycophenolate (CellCept) — 1000 mg PO BID (or mycophenolic acid 720 mg BID). Antiproliferative agent.
- 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.
Infection Timeline
- Month 0-1: Surgical site infections, UTI, donor-derived infections, CMV (especially D+/R-)
- 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."
Differential for Rising Creatinine
- Rejection (cellular or antibody-mediated)
- Tacrolimus toxicity (check trough level — supratherapeutic)
- BK virus nephropathy (check BK PCR)
- Obstruction (ureteral stricture, lymphocele — renal US)
- Pre-renal (dehydration, NSAID use, ACE/ARB)
- Recurrent disease (FSGS, IgA, diabetic nephropathy)
- CNI nephrotoxicity (chronic tacrolimus injury)
Rejection Treatment
- 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.
🧪 Workup
Workup for Rising Creatinine
- Tacrolimus trough — STAT. Supratherapeutic = CNI toxicity. Subtherapeutic = possible rejection.
- UA + urine culture — UTI is common post-transplant
- BK virus PCR — screen monthly for first 6 months, then q3 months. >10,000 copies = BK viremia requiring immunosuppression reduction.
- CMV PCR — if symptomatic or at high-risk period
- Donor-specific antibodies (DSA) — if AMR suspected
- Renal transplant ultrasound with Doppler — evaluate for hydronephrosis, perinephric collections (lymphocele, hematoma), vascular stenosis
- Transplant renal biopsy — gold standard for diagnosis. Banff classification. Indicated if creatinine rises >25% from baseline without clear cause.
Routine Surveillance Labs
- BMP, CBC, tacrolimus trough, LFTs, fasting glucose, lipid panel
- 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)
- CBC weekly — leukopenia (mycophenolate, valganciclovir), anemia, thrombocytopenia
- BK virus PCR monthly x 6 months, then q3 months x 2 years
- CMV PCR monthly for high-risk (D+/R-) during and after prophylaxis
- Fasting glucose — post-transplant diabetes (tacrolimus + steroids)
- 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
Maintenance
Tacrolimus + Mycophenolate + Prednisone. Check tacrolimus trough regularly.
Rising Cr
Rejection until proven otherwise. Tac level STAT, BK PCR, DSA, US, biopsy if unclear.
ACR Treatment
Pulse methylprednisolone 500 mg IV x 3 days. ATG if steroid-resistant.
AMR Treatment
Plasmapheresis + IVIG + Rituximab. Harder to treat than ACR.
Prophylaxis
TMP-SMX (PJP), Valganciclovir (CMV), Nystatin (candida). Duration varies by risk.
Infections
0-1mo: surgical/UTI. 1-6mo: CMV, BK, PJP. 6mo+: community, late CMV, PTLD.
Palliative/ICU
Palliative Extubation
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).
Monitoring by Severity
| Parameter | Massive / Submassive (ICU) | Low-Risk (Floor / Outpatient) |
|---|---|---|
| Vitals | Continuous telemetry + q1-2h. Arterial line if on pressors. | q4h. Continuous pulse ox × 24h. |
| Troponin | q6h × 24h then daily. Trending down = good. | Baseline if not already done. |
| BNP / NT-proBNP | Baseline + q24h. Falling = RV recovery. | Baseline only. |
| aPTT (if heparin drip) | q6h until therapeutic (60-80), then q12-24h. | N/A (on DOAC). |
| Platelet count | Baseline then q2-3 days (HIT screening if on heparin > 4 days). | Baseline. |
| Hemoglobin | Daily. Watch for bleeding (especially post-tPA). | Baseline. Repeat if bleeding signs. |
| Renal function | Daily BMP. Monitor Cr for contrast nephropathy (post-CTPA) and drug dosing. | Baseline. Confirm CrCl for DOAC dosing. |
| Echocardiography | Repeat in 24-48h for submassive. Assess RV recovery (TAPSE, RV/LV ratio). | Not routine. Only if symptoms persist. |
| Bleeding assessment | q shift: gums, GI (stool guaiac), hematuria, ecchymoses, access sites. | Educate patient on bleeding signs. |
| SpO2 / O2 requirement | Continuous. Increasing O2 need = deterioration → escalation. | Wean O2 to target SpO2 ≥ 92%. |
Escalation Triggers
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
- 48-72h follow-up after discharge (especially if outpatient PE treatment).
- 3-6 month reassessment: Duration decision (stop vs extend), DOAC adherence, bleeding screening.
- CTEPH screening: If persistent dyspnea at 3-6 months → echo → V/Q scan if elevated RVSP.
- 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).
📋 Summary
Summary
What It Is
Withdrawal of non-beneficial mechanical ventilation. NOT euthanasia. Ethically and legally supported.
Before
Family meeting, DNR order, discontinue monitors/alarms, comfort meds at bedside, pre-medicate with morphine.
Process
Remove restraints → disconnect monitors → suction → wean/extubate → nasal cannula for comfort → stay with family.
Key Meds
Morphine (dyspnea), Glycopyrrolate (secretions), Lorazepam (agitation), Haloperidol (delirium).
Guiding Principle
Titrate to COMFORT, not to respiratory rate or death. Principle of double effect.
Timeline
Death may occur minutes to days after extubation. Prepare families for this range.
Wards/Endo
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
• 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)
- Non-ICU patients: 100-180 mg/dL (pre-meal <140, random <180)
- Avoid hypoglycemia: <70 mg/dL is harmful. <54 = clinically significant. <40 = severe.
🚨 Management
Basal-Bolus Protocol
- Total daily dose (TDD): 0.4-0.5 units/kg/day. Reduce to 0.2-0.3 units/kg/day if elderly, CKD (eGFR <30), eating poorly, or high hypoglycemia risk.
- 50% as basal: Glargine (Lantus) or Detemir (Levemir) once daily (usually at bedtime or in the morning).
- 50% as bolus: Divided into 3 equal doses before each meal — Lispro (Humalog) or Aspart (NovoLog) before meals.
- Correction factor: 1700 / TDD = how many mg/dL 1 unit of insulin will drop glucose. Add correction to mealtime dose.
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.
Special Situations
Steroid-Induced Hyperglycemia
Prednisone causes AFTERNOON/EVENING hyperglycemia (peaks 4-8h after morning dose). The key is to match insulin to the glycemic pattern:
- Add NPH insulin with the morning prednisone dose — NPH peak matches prednisone glycemic peak.
- Starting dose: 0.1-0.2 units/kg. Uptitrate daily based on afternoon/evening glucose readings.
- When steroids are tapered, taper the NPH proportionally (or hyperglycemia will resolve and you risk hypoglycemia).
TPN (Total Parenteral Nutrition)
- Start with regular insulin IN the TPN bag at 1 unit per 10 g dextrose.
- Adjust daily based on glucose readings.
- Supplement with correction scale insulin SQ for persistent hyperglycemia.
- Roll 80% of previous day's correction insulin into the next TPN bag.
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.
🧪 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.
Daily Glucose Review
- Review all 4 POC glucose values from the past 24h
- Identify patterns: fasting highs = increase basal. Pre-dinner highs = increase lunch bolus. Overnight lows = reduce basal.
- Adjust insulin doses by 10-20% increments daily
💊 Medications
Medications
| Drug | Type | Onset / Peak / Duration | Notes |
|---|---|---|---|
| Glargine (Lantus) | Basal (long-acting) | 2-4h / peakless / 20-24h | 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. |
| NPH | Intermediate-acting | 1-3h / 4-12h / 12-18h | Key for steroid-induced hyperglycemia. Give with morning prednisone. Peak matches steroid glycemic peak. |
| 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.
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. AG closed. 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
- POC glucose q6h for NPO patients
- Q1h glucose for patients on IV insulin drip (ICU)
- Hypoglycemia alerts: <70 requires intervention. <54 = clinically significant. <40 = severe — consider dose reduction and workup.
- Daily insulin adjustment: review all 4 values, identify patterns, adjust by 10-20% per day.
- BMP daily — monitor K+ (insulin shifts K+ intracellularly), renal function (affects insulin clearance).
- A1c on admission — guides discharge insulin planning (A1c >9 likely needs insulin at discharge, A1c <8 may resume oral agents).
📋 Summary
Summary
Target
140-180 mg/dL (ICU). 100-180 (non-ICU). NICE-SUGAR
Protocol
Basal-bolus: TDD 0.4-0.5 u/kg. 50% basal (glargine) + 50% bolus (lispro AC meals). RABBIT 2
NPO Rule
NEVER hold basal. Reduce by 20-50%. Hold mealtime doses only.
Steroids
NPH with morning prednisone. Start 0.1-0.2 u/kg. Peak matches steroid glycemic peak.
Correction
1700 / TDD = how much 1 unit drops glucose (mg/dL).
Hypoglycemia
<70: D50 25 mL IV if NPO, or 15 g PO glucose. Recheck in 15 min.
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 |
| TACO | 1–6h | Dyspnea, HTN, JVD, pulmonary edema, elevated BNP | Diuresis (furosemide), O2, slow future transfusions |
| Delayed Hemolytic | 3–14 days | Falling Hgb, jaundice, positive DAT | Usually mild, supportive |
TRALI vs TACO (Board Favorite)
| Feature | TRALI | TACO |
|---|---|---|
| BNP | Low / normal | Elevated |
| CVP / JVD | Normal | Elevated |
| BP | Hypotension | Hypertension |
| CXR | Bilateral infiltrates (like ARDS) | Pulmonary edema, effusions |
| Diuretics | No response | Responds |
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.
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 |
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.
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 |
Summary
Summary
Most Common
FNHTR — fever + chills, no hemolysis. Acetaminophen.
Most Deadly
Acute hemolytic (ABO mismatch) and TRALI (#1 cause of transfusion death).
TRALI vs TACO
BNP is key. TRALI = low BNP. TACO = high BNP, responds to diuretics.
First Step
STOP transfusion. Send bag + sample to blood bank.
Nephro/ICU
Acid-Base Disorders
Systematic ABG interpretation: pH, primary disorder, compensation, anion gap, delta-delta, osmolar gap. MUDPILES, HARDUP, Winter’s formula, RTA types. Every ICU admission needs this.
Overview
Step-by-Step ABG Interpretation
- Step 1 — pH: <7.35 = acidemia, >7.45 = alkalemia
- Step 2 — Primary disorder: PaCO2 same direction as pH = metabolic. HCO3 opposite = respiratory
- Step 3 — Compensation: Winter’s formula: Expected PaCO2 = 1.5 × HCO3 + 8 ± 2
- Step 4 — Anion Gap: AG = Na − Cl − HCO3 (normal 12±2). Corrected: add 2.5 per 1g albumin below 4
- Step 5 — Delta-Delta: ΔAG/ΔHCO3. >2 = concurrent met alkalosis. <1 = concurrent NAGMA
- Step 6 — AGMA (MUDPILES): M ethanol · U remia · D KA · P ropylene glycol · I soniazid/Iron · L actic acidosis · E thylene glycol · S alicylates
- Step 7 — NAGMA (HARDUP): H yperalimentation, A ddison, R TA, D iarrhea, U reteral diversion, P ancreatic fistula
- Step 8 — Osmolar Gap: Measured − (2Na + Glu/18 + BUN/2.8). Gap >10 = toxic alcohol
RTA Types
| Type | Location | Urine pH | Serum K+ | Key Feature |
|---|---|---|---|---|
| Type 1 (Distal) | Distal tubule | >5.5 | Low | Cannot excrete H+. Kidney stones. Batlle 2001 |
| Type 2 (Proximal) | Proximal tubule | <5.5 | Low | Cannot reabsorb HCO3. Fanconi syndrome |
| Type 4 | Collecting duct | <5.5 | HIGH | Hypoaldosteronism (diabetes, ACEi). Most common RTA |
Respiratory Compensation Rules
| Primary Disorder | Expected Compensation | Formula |
|---|---|---|
| Metabolic acidosis | PaCO2 drops | Winter’s formula: PaCO2 = 1.5 × [HCO3] + 8 ± 2 |
| Metabolic alkalosis | PaCO2 rises | PaCO2 = 0.7 × [HCO3] + 21 ± 2 (or PaCO2 rises ~0.7 per 1 mEq/L HCO3 increase) |
| Acute respiratory acidosis | HCO3 rises | HCO3 rises 1 mEq/L per 10 mmHg PaCO2 increase |
| Chronic respiratory acidosis | HCO3 rises more | HCO3 rises 3.5 mEq/L per 10 mmHg PaCO2 increase |
| Acute respiratory alkalosis | HCO3 drops | HCO3 drops 2 mEq/L per 10 mmHg PaCO2 decrease |
| Chronic respiratory alkalosis | HCO3 drops more | HCO3 drops 5 mEq/L per 10 mmHg PaCO2 decrease |
Key principle: Compensation NEVER overcorrects. If the pH is fully normalized or overcorrected, there is a mixed disorder. Also: respiratory compensation for metabolic disorders occurs within hours. Renal compensation for respiratory disorders takes 3–5 days (acute vs chronic distinction matters).
Delta-Delta Ratio Interpretation
| ΔAG / ΔHCO3 Ratio | Interpretation | Clinical Example |
|---|---|---|
| <1 | AGMA + concurrent non-anion gap metabolic acidosis (NAGMA) | DKA + diarrhea (losing bicarb from two sources) |
| 1 – 2 | Pure AGMA (for every mEq/L AG rise, HCO3 drops proportionally) | Pure DKA, pure lactic acidosis |
| >2 | AGMA + concurrent metabolic alkalosis (HCO3 not dropping as expected) | DKA + vomiting, or AGMA in patient on chronic diuretics |
How to calculate: ΔAG = (measured AG − 12). ΔHCO3 = (24 − measured HCO3). Ratio = ΔAG / ΔHCO3. Always calculate when an elevated AG is present — it reveals hidden second and third disorders.
Mixed Acid-Base Disorders: Red Flags
- Normal pH with abnormal PaCO2 and HCO3 — two opposing disorders canceling out
- PaCO2 and HCO3 moving in opposite directions — mixed respiratory + metabolic disorder
- Compensation that appears excessive — second primary disorder, not just compensation
- AG elevated but HCO3 is normal or high — AGMA + metabolic alkalosis (delta-delta >2)
- AG elevated but HCO3 is disproportionately low — AGMA + NAGMA (delta-delta <1)
Classic triple disorder: Alcoholic patient with AGMA (ketoacidosis) + metabolic alkalosis (vomiting) + respiratory alkalosis (liver disease/hyperventilation). pH may look deceptively normal. Always calculate the AG and delta-delta in every ICU patient.
Workup
Labs
- ABG/VBG, BMP (calculate AG), albumin (correct AG), lactate, ketones
- Serum osmolality + calculated osm → osmolar gap
- Urine electrolytes + pH for NAGMA (urine AG = Na+K−Cl; positive = RTA)
- Toxic alcohol levels if osmolar gap elevated
Practice Cases
Case 1: pH 7.28, PaCO2 24, HCO3 11, Na 140, Cl 100, Alb 4.0
Acidemia. Met acidosis. Winter’s: expected PaCO2 = 24.5 (matches). AG = 29 (elevated). Delta-delta = 1.3 (pure AGMA). Simple AGMA. Check lactate, ketones, osmolar gap.
Case 2: pH 7.36, PaCO2 22, HCO3 12, Na 138, Cl 100, Alb 2.0
Normal pH but corrected AG = 31 (add 5 for low albumin). Delta-delta 1.6. Triple disorder: AGMA + met alkalosis + resp alkalosis. Albumin correction was essential.
Case 3: pH 7.52, PaCO2 48, HCO3 38, Na 140, Cl 92, K 2.8
Alkalemia. Met alkalosis with appropriate respiratory compensation. AG = 10 (normal). HypoK + met alkalosis = vomiting, diuretics, or hyperaldosteronism. Check urine Cl.
Management
Treatment by Disorder
| Disorder | Treatment |
|---|---|
| AGMA — DKA | Insulin drip + IVF + K repletion |
| AGMA — Lactic acidosis | Treat cause (sepsis, shock). Optimize perfusion |
| AGMA — Toxic alcohol | Fomepizole 15mg/kg + emergent dialysis |
| NAGMA — RTA Type 1/2 | Oral sodium bicarbonate |
| NAGMA — RTA Type 4 | Treat hyperK, fludrocortisone |
| Met alkalosis | Saline-responsive: NS + KCl. Saline-resistant: treat cause |
🔄 Updated Practice: Old teaching: give sodium bicarbonate for metabolic acidosis. Current practice: bicarb rarely helps and can worsen intracellular acidosis. In DKA, bicarb is only indicated if pH <6.9 (ADA guidelines). In lactic acidosis, treat the underlying cause (fluids, antibiotics, source control) — bicarb does not improve outcomes. Exception: bicarb IS indicated for TCA overdose (sodium channel blockade) and severe hyperkalemia.
Medications
Key Medications
| Drug | Indication | Dose |
|---|---|---|
| Sodium Bicarbonate | Severe acidosis (pH <7.1), TCA OD, RTA | 1–2 mEq/kg IV bolus or 150mEq in D5W drip |
| Fomepizole | Toxic alcohol ingestion | 15mg/kg IV load, then 10mg/kg q12h |
| Fludrocortisone | Type 4 RTA | 0.1mg PO daily |
| Acetazolamide | Resistant met alkalosis | 250–500mg IV/PO |
On Rounds
What is the delta-delta and when does it matter?
ΔAG/ΔHCO3. Detects hidden disorders. >2 = concurrent met alkalosis. <1 = concurrent NAGMA. 1–2 = pure AGMA.
Why correct the AG for albumin?
Albumin is the major unmeasured anion. In hypoalbuminemia, baseline AG is lower — you may miss an AGMA. Add 2.5 per 1g/dL below 4.
Walk through the 5-step approach to ABG interpretation.
1) pH: acidemia or alkalemia? 2) Primary disorder: does PaCO2 or HCO3 explain the pH? 3) Compensation adequate? Use Winter’s formula for met acidosis. 4) Anion gap: AG = Na − Cl − HCO3 (correct for albumin). 5) Delta-delta: if AG elevated, calculate ΔAG/ΔHCO3 to unmask hidden disorders.
What is Winter’s formula and when do you use it?
Winter’s formula: Expected PaCO2 = 1.5 × [HCO3] + 8 ± 2. Use it to check if respiratory compensation is appropriate in metabolic acidosis. If actual PaCO2 is higher than expected → concurrent respiratory acidosis. If lower than expected → concurrent respiratory alkalosis. Only applies to metabolic acidosis, not alkalosis.
What are the causes of anion gap metabolic acidosis (MUDPILES)?
M ethanol · U remia · D iabetic ketoacidosis · P ropylene glycol · I soniazid/Iron · L actic acidosis (#1 most common) · E thylene glycol · S alicylates. Always check lactate first (most common cause), then ketones, then osmolar gap for toxic alcohols.
What are the causes of non-anion gap metabolic acidosis (HARDUPS)?
H yperalimentation (TPN) · A ddison disease (adrenal insufficiency) · R enal tubular acidosis · D iarrhea (#1 most common — GI bicarbonate loss) · U reteral diversion (ileal conduit) · P ancreatic fistula/drainage · S aline infusion (dilutional acidosis). Use urine anion gap (Na+K−Cl) to distinguish renal vs GI loss: positive = RTA, negative = GI loss.
How do you identify a mixed acid-base disorder?
Red flags: 1) Normal pH with abnormal PaCO2/HCO3 (two disorders canceling). 2) PaCO2 and HCO3 moving in opposite directions. 3) Compensation that appears excessive (a second primary disorder). 4) Delta-delta >2 = hidden met alkalosis. <1 = hidden NAGMA. Always calculate AG and delta-delta in every ICU patient.
What is the urine anion gap and how does it help in NAGMA?
Urine AG = urine Na + urine K − urine Cl. In NAGMA, it distinguishes renal vs extrarenal causes. Negative UAG (Cl > Na+K) = kidneys are appropriately excreting NH4+ (acid) = GI loss (diarrhea). Positive UAG = kidneys cannot excrete acid = RTA. Memory trick: Negative = Normal response (GI cause), Positive = Problem in kidney (RTA).
Clinical Examples
📋 Case 1 — DKA with Anion Gap Metabolic Acidosis
Patient: 22F with T1DM, nausea/vomiting × 2 days, polyuria, abdominal pain. HR 112, BP 98/62, RR 28 (Kussmaul), SpO2 99%. Fruity breath odor.
Labs: pH 7.18, PaCO2 18, HCO3 7, Na 132, K 5.4, Cl 98, glucose 485, Cr 1.6, lactate 1.8.
Step-by-step ABG interpretation:
- Step 1: pH 7.18 = severe acidemia
- Step 2: HCO3 7 (low) = metabolic acidosis
- Step 3: Winter’s: expected PaCO2 = 1.5(7) + 8 ± 2 = 16.5–20.5. Actual 18 = appropriate compensation
- Step 4: AG = 132 − 98 − 7 = 27 (elevated). Albumin-corrected: same if albumin normal
- Step 5: ΔAG = 27 − 12 = 15. ΔHCO3 = 24 − 7 = 17. Ratio = 0.88 = AGMA + concurrent NAGMA (likely from vomiting-induced volume depletion or early renal loss)
Diagnosis: DKA with concurrent non-gap metabolic acidosis.
Management:
- IVF: NS bolus 1–2L, then 250–500 mL/hr. Switch to D5 half-NS when glucose <250
- Insulin: Regular insulin drip 0.1 u/kg/hr (no bolus per current ADA guidelines)
- Potassium: K 5.4 now, but will drop rapidly with insulin. Replete to >3.3 BEFORE starting insulin. Add 20–40 mEq KCl per liter of IVF
- Monitor: BMP q2h, AG trending. Close gap = resolving DKA. Transition to subQ insulin when AG closed, HCO3 ≥15, patient eating
Key lesson: The delta-delta revealed a concurrent NAGMA that would have been missed. Always complete all 5 steps. K+ is the most dangerous part of DKA management — replete before insulin.
📋 Case 2 — RTA with Non-Gap Acidosis
Patient: 45F with Sjögren syndrome, fatigue, muscle weakness × 3 weeks. HR 78, BP 118/72. Recurrent kidney stones. No diarrhea.
Labs: pH 7.30, PaCO2 28, HCO3 14, Na 140, K 2.8, Cl 116, albumin 4.0.
Step-by-step ABG interpretation:
- Step 1: pH 7.30 = acidemia
- Step 2: HCO3 14 = metabolic acidosis
- Step 3: Winter’s: expected PaCO2 = 1.5(14) + 8 ± 2 = 27–31. Actual 28 = appropriate compensation
- Step 4: AG = 140 − 116 − 14 = 10 (normal) → Non-anion gap metabolic acidosis (NAGMA)
- Step 5: No elevated AG, so delta-delta not applicable. Move to NAGMA workup
NAGMA workup:
- No diarrhea → not GI loss
- Urine AG: urine Na 45, K 30, Cl 15 → UAG = 45 + 30 − 15 = +60 (positive) → RTA
- Urine pH: 6.8 (>5.5 despite systemic acidosis) → Type 1 (distal) RTA
- Serum K+ low = consistent with Type 1 RTA (not Type 4, which has HIGH K+)
- Sjögren syndrome is a classic cause of distal RTA (autoimmune-mediated)
Management: Oral sodium bicarbonate or citrate supplementation (1–2 mEq/kg/day). Potassium citrate (treats acidosis AND prevents stones). Monitor electrolytes and renal function.
Key lesson: NAGMA + hypokalemia + high urine pH + positive urine AG = Type 1 RTA. Always check urine AG and urine pH in NAGMA to distinguish renal from GI causes.
📋 Case 3 — Mixed Acid-Base Disorder (Triple Disorder)
Patient: 55M with alcohol use disorder, found confused. Vomiting × 3 days. HR 105, BP 105/68, RR 24, SpO2 96%. Jaundiced, asterixis.
Labs: pH 7.40, PaCO2 25, HCO3 15, Na 138, K 3.0, Cl 95, albumin 2.0, lactate 2.4, serum ketones positive.
Step-by-step ABG interpretation:
- Step 1: pH 7.40 = normal pH — but do NOT stop here. Normal pH can hide serious pathology
- Step 2: HCO3 15 (low) AND PaCO2 25 (low) = metabolic acidosis + respiratory alkalosis? Need to investigate
- Step 3: Winter’s: expected PaCO2 = 1.5(15) + 8 ± 2 = 28.5–32.5. Actual 25 < expected → concurrent respiratory alkalosis (from hepatic encephalopathy/liver disease)
- Step 4: AG = 138 − 95 − 15 = 28. But albumin 2.0 → corrected AG = 28 + 2.5(4−2) = 33 (markedly elevated)
- Step 5: ΔAG = 33 − 12 = 21. ΔHCO3 = 24 − 15 = 9. Ratio = 21/9 = 2.3 (>2) → concurrent metabolic alkalosis (from vomiting)
Diagnosis: Triple acid-base disorder:
- 1) AGMA (alcoholic ketoacidosis + mild lactic acidosis)
- 2) Metabolic alkalosis (vomiting × 3 days)
- 3) Respiratory alkalosis (liver disease with hepatic encephalopathy)
Management: D5NS (dextrose treats AKA, saline repletes volume and Cl for met alkalosis). K and Mg repletion. Lactulose/rifaximin for hepatic encephalopathy. Thiamine before glucose. No insulin needed for AKA.
Key lesson: A normal pH does not mean normal acid-base status. This patient had three simultaneous disorders canceling each other out. Albumin correction revealed a massive AG that would have been missed. The delta-delta unmasked the hidden metabolic alkalosis.
Monitoring
| Parameter | Frequency | Target |
|---|---|---|
| ABG/VBG | q2–4h acute | Trend pH, PaCO2, HCO3 |
| BMP (AG) | q4–6h | Closing AG = resolving AGMA |
| Lactate | q2–4h if elevated | Trending down = improving |
| Osmolar gap | Serial if toxic alcohol | Closing gap + rising AG = metabolite formation → dialysis |
Summary
Summary
AGMA
MUDPILES: M ethanol · U remia · D KA · P ropylene glycol · I soniazid · L actic acid · E thylene glycol · S alicylates
NAGMA
HARDUP: H yperalimentation, A ddison, R TA, D iarrhea, U reteral diversion, P ancreatic fistula
Key Formulas
AG = Na-Cl-HCO3. Winter’s: 1.5(HCO3)+8±2. Osm gap = Measured − (2Na + Glu/18 + BUN/2.8)
Delta-Delta
>2 = hidden met alkalosis. <1 = concurrent NAGMA. Always calculate when AG elevated.
EMERGENTEM
Toxicology / Drug Overdose
Specific antidote protocols for highest-yield overdoses: acetaminophen, salicylate, TCA, opioid, BB/CCB. NEVER intubate a salicylate-toxic patient unless absolutely necessary.
Overview
Acetaminophen
- Rumack-Matthew nomogram — APAP level vs time to determine NAC need
- NAC: N-acetylcysteine 150mg/kg/1h → 50mg/kg/4h → 100mg/kg/16h Prescott 1979
- 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.
TCA
- Wide QRS (>100ms), sodium channel blockade, seizures
- 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
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 |
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) | Caustics, hydrocarbons, metals (iron, lithium, lead), alcohols, unprotected airway |
| Whole Bowel Irrigation | Sustained-release preps, iron, lithium, body packers | Any time if substance still in GI tract | Bowel obstruction, perforation, ileus, hemodynamic instability |
| Gastric Lavage | Rarely indicated — life-threatening ingestion within 1h | Within 1 hour | Caustics, hydrocarbons, impaired airway without intubation |
Activated Charcoal Dose: 1 g/kg (max 50g) single dose. Multi-dose activated charcoal (MDAC) q4h for: theophylline, carbamazepine, dapsone, quinine, phenobarbital.
Toxic Alcohol Workup
- 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)
- Methanol: Visual disturbance (“snowfield vision”), optic disc hyperemia, formic acid → retinal toxicity
- Ethylene glycol: Flank pain, calcium oxalate crystals in urine (envelope-shaped), AKI
- Isopropanol: Elevated osmolar gap but NO anion gap (metabolized to acetone, not an acid). Ketonemia without acidosis
Treatment: Fomepizole 15 mg/kg IV load (inhibits alcohol dehydrogenase). Dialysis if: pH < 7.25, renal failure, visual changes (methanol), level > 50 mg/dL.
Acetaminophen Nomogram (Rumack-Matthew)
- Draw APAP level at 4 hours post-ingestion (or ASAP if > 4h)
- Treatment line: 150 mcg/mL at 4h declining to 4.7 mcg/mL at 24h
- Level above the treatment line → start NAC immediately
- Unknown ingestion time or staggered: start NAC empirically if APAP > 10 mcg/mL or AST elevated
- NAC IV protocol (21h): 150 mg/kg/1h → 50 mg/kg/4h → 100 mg/kg/16h Prescott 1979
- NAC stop criteria: APAP undetectable, AST/ALT trending down, INR < 2, clinically improving
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) |
| Cause | Serotonergic drugs (SSRIs, MAOIs, tramadol, linezolid, MDMA) | Dopamine antagonists (haloperidol, metoclopramide) or dopamine withdrawal | Volatile anesthetics (sevoflurane, desflurane, isoflurane) and/or succinylcholine |
| Setting | Any setting (ward, ED, outpatient) | Any setting — often psychiatric patients | Operating room / post-anesthesia |
| Pathophysiology | Excess serotonin at 5-HT1A & 5-HT2A receptors | Central dopamine D2 receptor blockade in hypothalamus & basal ganglia | Uncontrolled Ca2+ release from sarcoplasmic reticulum via RYR1 mutation |
| Neuromuscular | Clonus, hyperreflexia, myoclonus (lower extremities > upper) | Lead-pipe rigidity, hyporeflexia, bradykinesia | Generalized rigidity (masseter spasm first), no clonus |
| Pupils | Mydriasis | Normal | Normal |
| GI | Diarrhea, hyperactive bowel sounds | Normal/decreased bowel sounds | Not prominent |
| Temp | ↑ (usually < 41°C) | ↑↑ (can be > 41°C) | ↑↑↑ (rapidly > 40°C, can exceed 43°C) |
| CK | Mildly elevated | Markedly elevated (> 1000, often > 10,000) | Massively elevated (> 10,000, can exceed 100,000) |
| Key Labs | Mild CK elevation, leukocytosis | CK ↑↑↑, WBC ↑, LFTs ↑, myoglobinuria | Hypercarbia (rising EtCO2 is often earliest sign), mixed respiratory & metabolic acidosis, hyperkalemia, myoglobinuria |
| Mental Status | Agitation, confusion | Altered, stupor, catatonia | Patient under anesthesia (may have delayed emergence) |
| Autonomic | Tachycardia, HTN, diaphoresis | Tachycardia, labile BP, diaphoresis, sialorrhea | Tachycardia, arrhythmias (hyperkalemia-driven), tachypnea, mottled skin |
| Treatment | Stop serotonergic drug, cyproheptadine 12mg then 4mg q4h, benzos, cooling | Stop antipsychotic, dantrolene 1–2.5 mg/kg IV, bromocriptine 2.5mg TID, cooling | Stop volatile anesthetic & succinylcholine, dantrolene 2.5 mg/kg IV q5min (max 10 mg/kg), 100% O2, aggressive cooling, treat hyperkalemia |
| Resolution | 24–72 hours | Days to weeks (7–14 days typical) | 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) →
Workup
Workup
- APAP level (4h post-ingestion), salicylate level, ethanol
- BMP, ABG, AG, osmolar gap, lactate, LFTs, coags
- ECG (QRS width, QTc)
- Urine drug screen (limited utility)
Management
Antidote Reference
| Toxin | Antidote | Dose |
|---|---|---|
| Acetaminophen | NAC | 150/50/100 mg/kg over 21h IV |
| Opioids | Naloxone | 0.04–0.4mg IV titrate |
| TCA | Sodium bicarbonate | 1–2 mEq/kg IV bolus |
| Beta-blockers | Glucagon | 3–5mg IV |
| CCB | High-dose insulin | 1u/kg/hr + D10W |
| Methanol/EG | Fomepizole | 15mg/kg IV load |
| Organophosphates | Atropine + Pralidoxime | Atropine 2mg IV q5min |
| Digoxin | DigiFab | Based on level or empiric 10–20 vials if acute, life-threatening |
| Benzodiazepines | Flumazenil | 0.2mg IV over 30s, then 0.3mg, then 0.5mg q1min (max 3mg). Only for iatrogenic oversedation in benzo-naive patients |
| Local anesthetic toxicity | Lipid emulsion (Intralipid) | 20% lipid emulsion 1.5 mL/kg IV bolus, then 0.25 mL/kg/min infusion |
| Cyanide | Hydroxocobalamin | 5g IV over 15 min (Cyanokit). Smoke inhalation with lactic acidosis |
| Iron | Deferoxamine | 15 mg/kg/hr IV (max 6g/day). Rose-colored urine = vin rosé sign |
| Warfarin / Coagulopathy | Vitamin K + FFP/PCC | Vitamin K 10mg IV; 4-factor PCC (KCentra) 25–50 u/kg for life-threatening bleed |
| Isoniazid | Pyridoxine (B6) | Gram-for-gram (5g IV if unknown amount). INH seizures refractory to benzos |
Medications
Detailed Dosing
| Drug | Dose | Notes |
|---|---|---|
| NAC IV | 150mg/kg in D5W/1h, 50mg/kg/4h, 100mg/kg/16h | Anaphylactoid reactions common first bag |
| Naloxone | 0.04mg → 0.4mg → 2mg titrate. Drip: 2/3 bolus/hr | Short t1/2; re-dosing needed for long-acting opioids |
| Glucagon | 3–5mg IV bolus, infusion 2–5mg/hr | BB OD. Causes vomiting (aspiration risk) |
| Insulin HIE | 1u/kg bolus then 1u/kg/hr + D10W | CCB OD. Monitor glucose q15min, K q1h |
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?
TCAs lower seizure threshold. Benzos raise it (protective). Flumazenil reverses benzo protection → refractory seizures → worsening acidosis → death.
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
- NAC stop criteria met: APAP undetectable + AST trending down + INR < 2 + clinical improvement
- 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.
Exam: Mydriasis, bilateral lower extremity clonus (spontaneous, > 3 beats), hyperreflexia, tremor, hyperactive bowel sounds, diarrhea. CK 680.
Clinical reasoning: Serotonergic agents (SSRI + tramadol) + rapid onset + clonus + hyperreflexia + diaphoresis. Hunter Criteria met (spontaneous clonus with serotonergic agent).
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
APAP
NAC 150/50/100. Nomogram at 4h. LFTs may be normal early.
Salicylate
Alkalinize urine. NEVER intubate unless necessary. Dialysis if >90.
TCA
Wide QRS → bicarb. No flumazenil.
BB/CCB
BB: Glucagon. CCB: High-dose insulin + D10W.
EMERGENTICU/EM
Intubation / RSI
Rapid Sequence Intubation. Pre-oxygenate, push induction + paralytic, confirm with ETCO2 waveform. Know your agents, contraindications, and difficult airway algorithm.
Overview
Indications
- Failure to protect airway (GCS ≤8), respiratory failure despite NIV, expected deterioration
The 7 P's of RSI
| # | Step | Details |
|---|---|---|
| 1 | Preparation | Equipment check (ETT, laryngoscope, bougie, LMA, suction, BVM), IV access, monitors, difficult airway plan |
| 2 | Pre-oxygenation | 3–5 min 100% O2 via NRB or HFNC. Goal: denitrogenation of FRC. Creates O2 reserve for apnea. |
| 3 | Pre-treatment | Optional. Fentanyl 1–2 mcg/kg for ICP concerns, lidocaine 1.5 mg/kg for reactive airways (controversial) |
| 4 | Paralysis with Induction | Push induction agent + paralytic simultaneously. Wait 45–60s for fasciculations to stop. |
| 5 | Protection & Positioning | Sniffing position (ear-to-sternal-notch alignment). Avoid cricoid pressure (Sellick) unless vomiting. |
| 6 | Placement | Direct or video laryngoscopy. Pass ETT through cords. Inflate cuff. Confirm with waveform ETCO2. |
| 7 | Post-intubation Management | Sedation + analgesia, initial vent settings, CXR, ABG at 30 min. Secure tube. |
RSI Sequence
- Pre-oxygenate 3–5min 100% O2, HFNC apneic oxygenation, HOB 20–30°
- Push induction + paralytic simultaneously → wait 45–60s → laryngoscopy
- Confirm with continuous waveform ETCO2
ETCO2 waveform is the GOLD STANDARD. Auscultation alone is NOT sufficient. No waveform = esophageal until proven otherwise.
Induction Agents
| Agent | Dose | Pros | Cons |
|---|---|---|---|
| Etomidate | 0.3mg/kg | Hemodynamically neutral | Adrenal suppression |
| Ketamine | 1–2mg/kg | Bronchodilator, maintains BP. Best for asthma/sepsis | Emergence reactions |
| Propofol | 1–2mg/kg | Fast onset | Drops BP — avoid in hypotension |
Paralytics
| Agent | Dose | Onset | Contraindications |
|---|---|---|---|
| Succinylcholine | 1–1.5mg/kg | 45s (fastest) | HyperK, burns >48h, crush, NMD, malignant hyperthermia |
| Rocuronium | 1.2mg/kg | 60s | Reversible with sugammadex |
🔄 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.
Pre-Assessment
Checklist
- LEMON airway assessment, equipment ready (ETT, laryngoscope, bougie, LMA, suction)
- Hemodynamics: optimize BEFORE intubation, push-dose vasopressors ready
- Pre-oxygenation: 3–5min NRB or HFNC, HOB elevated
LEMON Difficult Airway Assessment
| Letter | Assessment | Concerning Findings |
|---|---|---|
| L | Look externally | Facial trauma, large tongue, short neck, obesity, beard, cervical collar |
| E | Evaluate 3-3-2 rule | < 3 fingers mouth opening, < 3 fingers mentum to hyoid, < 2 fingers hyoid to thyroid notch |
| M | Mallampati | Class III (soft palate only) or IV (hard palate only) = difficult view |
| O | Obstruction / Obesity | Epiglottitis, peritonsillar abscess, angioedema, neck mass, BMI > 30 |
| N | Neck mobility | C-spine immobilization, ankylosing spondylitis, rheumatoid arthritis (C1-2 instability) |
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 IBW (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. | Awake-sedation, extubation readiness, delirium-prone |
| Midazolam (Versed) | 1–5 mg/h | Anxiolysis, anti-epileptic | 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 | Pros | Cons | Contraindications |
|---|---|---|---|---|---|---|
| Etomidate | 0.3 mg/kg IV | 15–45s | 3–12 min | Hemodynamically neutral, cerebro-protective (lowers ICP, maintains CPP) | Adrenal suppression (single dose clinically insignificant per Jabre, 2009), myoclonus, no analgesic properties | Relative: sepsis/adrenal insufficiency (some avoid, data equivocal) |
| Ketamine | 1–2 mg/kg IV | 45–60s | 10–20 min | Bronchodilator (best for asthma), sympathomimetic (maintains BP), analgesic, does not suppress respirations | Emergence reactions (give midazolam), hypersalivation (give glycopyrrolate), increases HR | Relative: severe uncontrolled HTN. Old concern about raising ICP is largely debunked. |
| Propofol | 1–2 mg/kg IV | 15–30s | 5–10 min | Fastest onset, anti-epileptic, lowers ICP, smooth induction | Significant hypotension (drops MAP 20–30%), myocardial depression, apnea, pain on injection | Avoid in hemodynamic instability, shock, hypovolemia, egg/soy allergy (controversial) |
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 | Very few. True allergy only. |
| Side effects | Fasciculations, hyperkalemia (+0.5 mEq/L), bradycardia (especially repeat doses or pediatrics), masseter spasm, malignant hyperthermia | Minimal. No hyperkalemia. No fasciculations. |
| Advantage | Ultra-short duration (returns spontaneous breathing faster if you cannot intubate) | Reversible with sugammadex, safer profile, fewer contraindications |
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
Gold Standard
Waveform ETCO2. No waveform = esophageal.
Induction
Etomidate (neutral), Ketamine (asthma/sepsis), Propofol (avoid in hypotension).
Paralytic
Sux 1.5mg/kg (45s, fastest) or Roc 1.2mg/kg (sugammadex reversible).
Post-Intubation
TV 6–8mL/kg IBW, RR 14–16, FiO2 wean, PEEP 5. Sedation + CXR.
RoundsRx Licensed Content - Unauthorized Use Prohibited
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.
Overview
Approach
- Chest pain → ECG within 10 min → Troponin
- ST elevation in 2 contiguous leads = STEMI → cath lab NOW
- No ST elevation + troponin rising = NSTEMI
- Normal ECG + normal troponin = unstable angina or non-cardiac
HEART Score
| Component | 0 | 1 | 2 |
|---|---|---|---|
| History | Slightly suspicious | Moderately | Highly suspicious |
| ECG | Normal | Non-specific | ST deviation |
| Age | <45 | 45–64 | ≥65 |
| Risk Factors | None | 1–2 | ≥3 or known CAD |
| Troponin | Normal | 1–3×ULN | >3×ULN |
0–3 = Low risk (consider discharge). 4–6 = Moderate (admit). 7–10 = High (early invasive).
STEMI vs NSTEMI vs Unstable Angina
| Feature | STEMI | NSTEMI | Unstable Angina |
|---|---|---|---|
| Pathology | Complete coronary occlusion (transmural) | Partial occlusion / subtotal thrombus | Partial occlusion, no necrosis |
| ECG | ST elevation ≥1mm in 2 contiguous leads (or new LBBB) | ST depression, T-wave inversion, or nonspecific | Normal or nonspecific changes |
| Troponin | Elevated (rises within 3–6h) | Elevated | Normal |
| Cath timing | Emergent PCI (<90 min door-to-balloon) | Early invasive (2–24h) or ischemia-guided | Risk-stratified approach |
| Mortality (30d) | ~6–8% | ~3–5% | <1% |
STEMI Equivalents: New LBBB + ACS symptoms, de Winter T-waves (upsloping ST depression + tall T-waves in precordial leads), posterior MI (ST depression V1–V3 + tall R waves — get posterior leads V7–V9), and Wellens syndrome (deeply inverted or biphasic T-waves V2–V3 = critical LAD stenosis).
Type 1 vs Type 2 MI
| Feature | Type 1 MI (Plaque Rupture) | Type 2 MI (Supply-Demand Mismatch) |
|---|---|---|
| Mechanism | Atherosclerotic plaque rupture/erosion → thrombotic occlusion | Oxygen supply-demand mismatch WITHOUT plaque rupture |
| Triggers | Spontaneous plaque event | Tachycardia, anemia, sepsis, hypotension, respiratory failure, hypertensive crisis |
| Treatment | Antiplatelet + anticoag + PCI/CABG | 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 Classification (Acute MI)
| Killip Class | Findings | 30-Day Mortality |
|---|---|---|
| I | No HF signs | ~6% |
| II | Rales, S3, JVD | ~17% |
| III | Frank pulmonary edema | ~38% |
| IV | Cardiogenic shock (SBP <90, end-organ hypoperfusion) | ~67% |
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
- CBC, BMP, coags, BNP, CXR
Management
Initial Management (ALL ACS)
| Intervention | Details |
|---|---|
| Aspirin | 325mg chewed immediately |
| O2 | Only if SpO2 <90% DETO2X-AMI AVOID |
| Nitroglycerin | 0.4mg SL q5min ×3. AVOID: RV infarct, SBP <90, PDE5i use |
| Heparin | UFH 60u/kg bolus → 12u/kg/hr (or enoxaparin 1mg/kg q12h) |
| Beta-blocker | 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.
Door-to-Balloon Time Targets
| Scenario | Target | Details |
|---|---|---|
| STEMI — PCI-capable center | <90 min door-to-balloon | Activate cath lab from ED or EMS. Goal <60 min for walk-in STEMIs |
| STEMI — transfer to PCI center | <120 min first medical contact to device | If transfer time exceeds this, give fibrinolytics at presenting hospital |
| Fibrinolysis (if PCI unavailable) | <30 min door-to-needle | Tenecteplase (TNK) weight-based single bolus. Rescue PCI if no ST resolution by 60–90 min |
| NSTEMI — early invasive | 2–24 hours | High-risk features: refractory angina, hemodynamic instability, new HF, GRACE >140 TIMACS, 2009 |
| NSTEMI — ischemia-guided | Selective cath | 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 |
| Clopidogrel | 600 mg (PCI) or 300 mg | 75 mg daily × 12 mo | Alternative. CYP2C19 poor metabolizers = reduced efficacy |
| GP IIb/IIIa | Eptifibatide or tirofiban | Infusion during/post PCI | High thrombus burden only. NOT routine upstream. EARLY-ACS, 2009 |
| 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
TIMI & GRACE Risk Scores
| Score | Components | Interpretation |
|---|---|---|
| TIMI (NSTEMI/UA) | Age ≥65, ≥3 CAD RFs, known CAD, ASA use past 7d, ≥2 angina episodes/24h, ST deviation, elevated troponin (1 pt each, max 7) | 0–2: Low (5%). 3–4: Intermediate. 5–7: High (41%) → early invasive |
| GRACE | Age, HR, SBP, Cr, Killip class, cardiac arrest, ST deviation, troponin (calculator-based) | <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.
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
- Atorvastatin 80 mg PO. NTG 0.4 mg SL (anterior wall, no RV involvement)
Cath findings: 100% proximal LAD occlusion. DES placed. TIMI 3 flow restored. Door-to-balloon time: 68 minutes.
Post-PCI orders:
- ICU admission, continuous telemetry × 48h (VT/VF risk highest early)
- Echo next AM → EF 35% with anterior wall hypokinesis
- Start ABCDE: lisinopril 2.5 mg, metoprolol 25 mg BID, atorvastatin 80 mg, ASA 81 + ticagrelor 90 BID, eplerenone 25 mg (EF <40%)
- Cardiac rehab referral before discharge
Key lesson: Anterior STEMI = large territory at risk. Time is myocardium. ABCDE medications are essential at discharge, especially with reduced EF.
📋 Case 2 — NSTEMI Risk Stratification
Patient: 72F with DM, HTN, HLD. Substernal pressure at rest × 2h, now improving. HR 82, BP 158/92, SpO2 97%.
ECG: ST depression 1.5 mm in V4–V6, T-wave inversions in I, aVL. No ST elevation.
Labs: hs-troponin 0h = 85 ng/L (elevated), 3h = 142 ng/L (rising). Cr 1.1, K 4.2.
Risk stratification:
- HEART score: H=2, E=2, A=2, R=2, T=2 = 10 (high risk)
- TIMI score: Age ≥65, ≥3 RFs, ST deviation, elevated troponin, ≥2 episodes = 5/7 (high risk)
- GRACE score: 156 (high risk, >3% in-hospital death) → early invasive strategy <24h
Management:
- ASA 325 mg + ticagrelor 180 mg load + heparin drip
- Atorvastatin 80 mg, metoprolol 25 mg (HR/BP allow it)
- 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.
Labs: hs-troponin 0h = 65 ng/L, 3h = 78 ng/L (mildly elevated, stable). Lactate 3.8. WBC 18k.
Clinical reasoning:
- 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 Min
ECG + ASA 325 chewed + IV + troponin. STEMI = cath NOW.
HEART Score
0–3 low (discharge), 4–6 moderate (admit), 7–10 high (invasive).
All ACS
ASA + P2Y12 + anticoag + statin + BB if stable.
Avoid NTG In
RV infarct, SBP <90, PDE5i within 24–48h.
Cardio
Aortic Stenosis
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.
Overview
Etiology & Presentation
- Causes: Degenerative/calcific (elderly), bicuspid aortic valve (younger)
- Triad (SAD): Syncope, Angina, Dyspnea (HF)
- Murmur: Crescendo-decrescendo systolic, radiates to carotids. Pulsus parvus et tardus
Severity
| Parameter | Mild | Moderate | Severe |
|---|---|---|---|
| AVA (cm²) | >1.5 | 1.0–1.5 | <1.0 |
| Mean Gradient | <25 | 25–40 | >40 |
| Vmax (m/s) | <3.0 | 3.0–4.0 | >4.0 |
Do NOT give vasodilators aggressively in severe AS. These patients are preload-dependent. Vasodilation → syncope → death.
Symptom Triad & Natural History
| Symptom | Mechanism | Mean Survival Without AVR |
|---|---|---|
| Angina | LVH → ↑ O2 demand + ↓ coronary perfusion pressure | ~5 years |
| Syncope | Fixed CO + peripheral vasodilation (exercise) → cerebral hypoperfusion | ~3 years |
| Heart Failure | Chronic pressure overload → systolic dysfunction → decompensation | ~2 years |
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.
Classic Murmur Description
- Type: Crescendo-decrescendo (diamond-shaped) systolic ejection murmur
- 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
Severe AS
AVA <1.0, gradient >40, Vmax >4.0.
Symptoms
SAD: Syncope, Angina, Dyspnea. Once present = valve replacement.
Treatment
Symptomatic = TAVR or SAVR. No medical therapy changes outcomes.
Danger
Avoid vasodilators. Preload-dependent.
Cardio
Mitral Regurgitation
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.
Overview
Acute vs Chronic
| Feature | Acute MR | Chronic MR |
|---|---|---|
| Causes | Papillary rupture (post-MI), endocarditis, chordae rupture | Myxomatous (MVP), rheumatic, functional (LV dilation) |
| Presentation | Flash pulmonary edema, cardiogenic shock | Asymptomatic years → dyspnea |
| Treatment | EMERGENCY SURGERY | Surgery when criteria met |
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.
Primary vs Secondary MR
| Feature | Primary (Degenerative) MR | Secondary (Functional) MR |
|---|---|---|
| Pathology | Intrinsic valve disease (leaflets, chordae, papillary muscles) | Normal valve; MR from LV dilation/dysfunction |
| Common causes | Myxomatous/MVP, rheumatic, endocarditis, radiation | Ischemic cardiomyopathy, dilated cardiomyopathy |
| Treatment | Mitral valve repair (preferred) or replacement | 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.
MitraClip (Transcatheter Edge-to-Edge Repair) Criteria
| Criterion | COAPT Eligibility |
|---|---|
| MR severity | 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
Flash pulm edema, papillary rupture. EMERGENCY surgery.
Surgery Triggers
Symptomatic, EF ≤60%, LVESD ≥40mm.
EF Trap
EF falsely preserved. 60% = significant dysfunction.
Secondary MR
Optimize GDMT first. MitraClip (COAPT) if persistent.
EMERGENTEM/Vascular
Acute Limb Ischemia
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.
Time-to-Intervention Urgency
| Rutherford Class | Time Window | Intervention |
|---|---|---|
| I — Viable | Not immediately threatened | Heparin + elective angiography within hours |
| IIa — Marginally threatened | Hours (urgent) | Catheter-directed thrombolysis (tPA 0.5–1 mg/hr × 12–24h) |
| IIb — Immediately threatened | Minutes to hours (emergent) | Surgical embolectomy or bypass — NO time for thrombolysis |
| III — Irreversible | Too late for salvage | Amputation ± palliative care. Revascularization risks fatal reperfusion injury |
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.
Workup
Workup
- ABI, CTA (if stable). Labs: CBC, BMP (K+), lactate, CK, coags
- ECG for AF (common embolic source)
- Do NOT delay heparin for imaging
Management
Management
| Step | Action |
|---|---|
| 1 | Heparin 80u/kg bolus → 18u/kg/hr IMMEDIATELY |
| 2 | Vascular surgery consult STAT |
| 3 | Catheter-directed thrombolysis, embolectomy, or bypass |
| 4 | Post-reperfusion: watch compartment syndrome → fasciotomy |
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
- Completion angiogram shows restored flow. Pedal pulses return
- 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
- Long-term: Dual antiplatelet (ASA + clopidogrel), statin, smoking cessation, DM optimization
Key lesson: Rutherford IIb (motor deficit) = go to OR, not cath lab. Thrombotic ALI in PAD often needs bypass rather than simple embolectomy.
📋 Case 3 — Reperfusion Injury After Revascularization
Patient: 58M s/p emergent embolectomy for Rutherford IIb ALI (6-hour ischemia time). Pulses restored in OR. Four hours post-op, develops tense calf swelling, escalating pain, and oliguria.
Labs: K+ 6.4, CK 45,000, Cr 2.8 (baseline 1.0), pH 7.22, lactate 8.5, urine dark brown (myoglobinuria).
Diagnosis: Reperfusion injury with rhabdomyolysis, hyperkalemia, and metabolic acidosis. Tense calf = compartment syndrome.
Management:
- Hyperkalemia: Calcium gluconate 1g IV (cardiac membrane stabilization), insulin 10 units + D50, kayexalate. Continuous telemetry for peaked T-waves
- Rhabdomyolysis: Aggressive IVF (target UOP 200–300 mL/hr), sodium bicarbonate drip to alkalinize urine (target urine pH >6.5)
- Compartment syndrome: Compartment pressures 42 mmHg → emergent four-compartment fasciotomy
- 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
6 P’s
Pain, Pallor, Pulselessness, Poikilothermia, Paresthesia, Paralysis.
First Step
Heparin 80u/kg NOW + vascular surgery STAT.
Treatment
Thrombolysis, embolectomy, or bypass by Rutherford class.
Post-Reperfusion
Compartment syndrome, hyperK, rhabdo, acidosis.
URGENTGI/Surgery
Bowel Obstruction
SBO (#1 cause: adhesions) vs LBO (#1 cause: colorectal cancer). Know when to manage conservatively vs when strangulation signs mandate the OR. Sigmoid volvulus = scope first. Cecal volvulus = surgery.
Overview
SBO vs LBO
| Feature | SBO | LBO |
|---|---|---|
| #1 Cause | Adhesions | Colorectal cancer |
| Other | Hernias, malignancy, Crohn | Volvulus (sigmoid > cecal) |
| Conservative | NGT, NPO, IVF ×48–72h | Depends on cause |
| Surgery | Complete, strangulation, failure to resolve | Cancer → resection. Cecal volvulus → surgery |
Volvulus
| Type | First-Line | Definitive |
|---|---|---|
| Sigmoid | Endoscopic decompression | Interval resection |
| Cecal | Surgery (scope does NOT work) | Right hemicolectomy |
Strangulation signs = SURGICAL EMERGENCY: fever, peritoneal signs, free air, leukocytosis, lactate elevation, non-reducible hernia.
CT Imaging Findings
| Finding | Significance |
|---|---|
| Transition point | 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.
Labs: WBC 9.2, lactate 1.1, BMP notable for K+ 3.2, Cr 1.3 (baseline 0.8, dehydration).
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.
Labs: WBC 22,000, lactate 6.8, BMP with K+ 5.1, Cr 2.1, metabolic acidosis (pH 7.28, bicarb 16).
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.
Management:
- Resuscitation: 2L LR bolus, NGT (feculent output), Foley, broad-spectrum antibiotics (pip-tazo 4.5g IV)
- 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
- Staging workup: CT chest (no pulmonary mets), liver MRI confirms 3 bilobar hepatic metastases. Biopsy: moderately differentiated adenocarcinoma. KRAS mutant. Stage IVA
- 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
SBO
#1 adhesions. NGT + NPO + IVF. Surgery if strangulation/failure 48–72h.
LBO
#1 CRC. Sigmoid volvulus: scope. Cecal volvulus: surgery.
Strangulation
Fever, peritonitis, free air, WBC, lactate = OR NOW.
SBO vs Ileus
Mechanical (transition point) vs functional (diffuse, no cutoff).
EMERGENTSurgery/ID
Necrotizing Fasciitis / Gas Gangrene
Rapidly progressive soft tissue infection. Mortality increases ~25% per hour of surgical delay. Pain OUT OF PROPORTION to exam is the hallmark. Surgical debridement IS the treatment. CT can miss early cases.
Overview
Classification
| Type | Organisms | Risk Factors |
|---|---|---|
| Type 1 (Polymicrobial) | Mixed aerobic + anaerobic | Diabetes, post-surgical, immunocompromised |
| Type 2 (Monomicrobial) | Group A Strep | Young, healthy, minor trauma |
| Gas Gangrene | C. perfringens | Trauma, surgical wounds |
Clinical Features
- Pain OUT OF PROPORTION to exam — hallmark
- Rapidly spreading erythema, crepitus, bullae, dusky/necrotic skin
- Systemic toxicity: sepsis, shock. LRINEC ≥6 suggestive
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. Every hour of delay increases mortality ~25%.
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%. Every hour of delay in surgical debridement increases mortality by approximately 25%. 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
- Vancomycin + piperacillin-tazobactam + clindamycin (triple therapy: MRSA + GNR/anaerobes + toxin suppression)
- 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." The mortality of necrotizing fasciitis doubles with every hour of surgical delay. 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)
- IVIG 1-2 g/kg × 1 dose (neutralizes streptococcal superantigens in STSS)
- 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
Hallmark
Pain OUT OF PROPORTION + rapid progression + systemic toxicity.
Treatment
SURGICAL DEBRIDEMENT. Vanc + pip-tazo + clindamycin.
Clindamycin
TOXIN SUPPRESSION (protein synthesis inhibitor stops exotoxin production).
Mortality
~25% increase per hour of surgical delay. CT can miss early. Operate if suspected.
High-YieldID / Wards
Herpes Simplex (HSV)
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). |
| HSV keratitis | Eye pain, photophobia, tearing, decreased vision. Dendritic ulcer on slit-lamp fluorescein exam. | OPHTHALMOLOGY EMERGENCY — can cause corneal scarring and blindness. Treat with topical ganciclovir or trifluridine. Do NOT give topical steroids (worsens viral keratitis). |
| HSV encephalitis EMERGENCY | Fever, headache, altered mental status, seizures, focal neurologic deficits. Temporal lobe predilection on MRI. | 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 | Oral: 200–800 mg, 2–5x daily (varies by indication) IV: 5–10 mg/kg q8h | 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
Primary Genital
Valacyclovir 1g PO BID × 7–10 days. Start early. Most severe episode. Screen for STIs.
Recurrent Genital
Valacyclovir 500 mg BID × 3 days (episodic). Start at prodrome. Patient-initiated therapy.
Suppressive
Valacyclovir 500 mg–1g daily. For ≥6/year, serodiscordant couples, severe impact. Reduces transmission ~50%.
HSV Encephalitis
Acyclovir 10 mg/kg IV q8h × 14–21 days. START IMMEDIATELY. Temporal lobe on MRI. 70% fatal untreated.
Diagnosis
HSV PCR swab (gold standard for active lesions). Type-specific IgG for serology. NEVER order HSV IgM.
Pregnancy
Suppress from 36 weeks. C-section if active lesions at labor. Primary HSV near delivery = highest neonatal risk.
📄 One Pager
Herpes Simplex (HSV) — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
HERPES SIMPLEX (HSV) — AT A GLANCE
📋 Diagnose: HSV PCR swab (active lesions), type-specific IgG (serology). Never IgM.
🧪 Workup: PCR swab unroofed vesicle. Encephalitis: MRI + CSF PCR + start acyclovir empirically.
⚡ Treat: Valacyclovir 1g BID × 7–10d (primary), 500 mg BID × 3d (recurrent), 500 mg–1g daily (suppressive).
💊 Encephalitis: Acyclovir 10 mg/kg IV q8h × 14–21d. DO NOT WAIT for results.
🤰 Pregnancy: Suppress from 36 wk. C-section if active lesions at labor.
⚠️ Resistance: Suspect if no improvement at 10d in immunocompromised → foscarnet.
🧪 Workup: PCR swab unroofed vesicle. Encephalitis: MRI + CSF PCR + start acyclovir empirically.
⚡ Treat: Valacyclovir 1g BID × 7–10d (primary), 500 mg BID × 3d (recurrent), 500 mg–1g daily (suppressive).
💊 Encephalitis: Acyclovir 10 mg/kg IV q8h × 14–21d. DO NOT WAIT for results.
🤰 Pregnancy: Suppress from 36 wk. C-section if active lesions at labor.
⚠️ Resistance: Suspect if no improvement at 10d in immunocompromised → foscarnet.
Rising IncidenceID / Wards
Syphilis
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) | Early: headache, meningitis, cranial nerve palsies (CN VII, VIII), uveitis, hearing loss. Late: tabes dorsalis (lightning pains, Argyll Robertson pupils, ataxia), general paresis (dementia, personality change). | 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
Primary/Secondary/Early Latent
Benzathine PCN G 2.4 MU IM × 1 dose. RPR follow-up at 6 and 12 months.
Late Latent / Unknown
Benzathine PCN G 2.4 MU IM weekly × 3 doses. RPR at 6, 12, 24 months.
Neurosyphilis
IV penicillin G 18–24 MU/day × 10–14 days. LP follow-up at 6 months. Desensitize if PCN allergy.
Diagnosis
RPR/VDRL (screen + follow titers) + FTA-ABS/TP-PA (confirm). CSF VDRL for neurosyphilis (specific, not sensitive).
Screen
All pregnant women, HIV+, MSM, other STI diagnosis. Always co-test for HIV.
Jarisch-Herxheimer
Fever/rigors within 24h of first PCN dose. Self-limited. Warn patients. NSAIDs for symptoms.
📄 One Pager
Syphilis — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
SYPHILIS — AT A GLANCE
📋 Stages: Primary (painless chancre) → Secondary (rash palms/soles) → Latent → Tertiary/Neurosyphilis
🧪 Dx: RPR/VDRL (screening + follow titers) + FTA-ABS (confirmation). CSF VDRL for neurosyphilis.
⚡ Tx Early: Benzathine PCN G 2.4 MU IM × 1. Late: × 3 weekly doses. Neuro: IV PCN G × 10–14d.
⚠️ Jarisch-Herxheimer: Fever within 24h of first dose. Self-limited. Warn patient.
🤰 Pregnancy: Penicillin ONLY. Desensitize if allergic. Screen at first prenatal visit.
🔍 Follow: RPR at 6, 12 (and 24 for late). Expect 4-fold decline. If not → retreat or LP.
🧪 Dx: RPR/VDRL (screening + follow titers) + FTA-ABS (confirmation). CSF VDRL for neurosyphilis.
⚡ Tx Early: Benzathine PCN G 2.4 MU IM × 1. Late: × 3 weekly doses. Neuro: IV PCN G × 10–14d.
⚠️ Jarisch-Herxheimer: Fever within 24h of first dose. Self-limited. Warn patient.
🤰 Pregnancy: Penicillin ONLY. Desensitize if allergic. Screen at first prenatal visit.
🔍 Follow: RPR at 6, 12 (and 24 for late). Expect 4-fold decline. If not → retreat or LP.
CommonID / Wards
Herpes Zoster (Shingles)
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.
- Risk factors: age >50 (most important), immunosuppression (transplant, HIV, chemo, steroids), stress, trauma
- 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. |
| VZV vasculopathy / stroke | Stroke weeks–months after zoster (especially ophthalmic zoster). VZV infects cerebral arteries. | 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. |
Prevention — Shingrix Vaccine
- Shingrix (recombinant adjuvanted VZV vaccine) — 2 doses IM, 2–6 months apart
- >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.
💊 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
Treatment
Valacyclovir 1g PO TID × 7 days. Start within 72h. IV acyclovir if immunocompromised/disseminated.
Hutchinson Sign
Vesicles on nose tip = V1 nasociliary involvement. 76% risk of ocular complications. Urgent ophthalmology consult.
Ramsay Hunt
Ear vesicles + facial palsy + hearing loss/vertigo. Antiviral + prednisone. Worse recovery than Bell’s palsy.
PHN Prevention
Early antivirals reduce risk. Treat with gabapentin/pregabalin, lidocaine patch, duloxetine. Common in >60y.
Vaccine
Shingrix: 2 doses IM, >90% effective. All adults ≥50. Immunocompromised ≥19. Non-live = safe.
Isolation
Contact precautions (localized) or airborne + contact (disseminated) until crusted. Can cause chickenpox in non-immune.
📄 One Pager
Herpes Zoster (Shingles) — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
HERPES ZOSTER — AT A GLANCE
📋 Dx: Clinical (unilateral dermatomal vesicles). VZV PCR swab if uncertain.
⚡ Tx: Valacyclovir 1g PO TID × 7d (start within 72h). IV acyclovir 10 mg/kg q8h if disseminated/immunocompromised.
👁️ HZO: V1 involvement + Hutchinson sign → urgent ophthalmology. Treat regardless of timing.
👂 Ramsay Hunt: Ear vesicles + facial palsy + hearing loss → antiviral + prednisone.
🔥 PHN: Pain >90 days. Gabapentin/pregabalin first-line. Lidocaine patch for localized pain.
💉 Prevent: Shingrix × 2 doses for all ≥50. >90% effective. Non-live = safe in immunocompromised.
⚡ Tx: Valacyclovir 1g PO TID × 7d (start within 72h). IV acyclovir 10 mg/kg q8h if disseminated/immunocompromised.
👁️ HZO: V1 involvement + Hutchinson sign → urgent ophthalmology. Treat regardless of timing.
👂 Ramsay Hunt: Ear vesicles + facial palsy + hearing loss → antiviral + prednisone.
🔥 PHN: Pain >90 days. Gabapentin/pregabalin first-line. Lidocaine patch for localized pain.
💉 Prevent: Shingrix × 2 doses for all ≥50. >90% effective. Non-live = safe in immunocompromised.
EmergencyID / Ortho
Septic Arthritis
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
Microbiology
| Population | Most Common Organisms | Key Notes |
|---|---|---|
| Adults (non-gonococcal) | Staphylococcus aureus (60–70%), Streptococcus spp. (15–20%) | MRSA prevalence increasing — consider empiric vancomycin. GNRs in elderly, immunocompromised, IVDU. |
| Young sexually active adults | Neisseria gonorrhoeae | 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). |
| IVDU | S. aureus, Pseudomonas, Serratia | Unusual joints (sacroiliac, sternoclavicular). Consider GNR coverage. |
| Prosthetic joint | S. aureus, coagulase-negative Staph, Cutibacterium acnes | Early (<3 months): aggressive organisms. Late (>12 months): low-virulence organisms (CoNS, C. acnes). Hold cultures ≥14 days for slow-growers. |
| Animal/human bites | Pasteurella multocida (cat), Eikenella corrodens (human), polymicrobial | Amoxicillin-clavulanate for bite wounds near joints. If joint penetrated, treat as septic arthritis. |
Risk Factors
- Pre-existing joint disease: Rheumatoid arthritis (RA), osteoarthritis, gout, crystal arthropathy — RA has 10x increased risk
- Prosthetic joint — foreign material = biofilm risk
- Immunosuppression: Diabetes, HIV, corticosteroids, biologics (TNF inhibitors), malignancy
- Skin breakdown: Psoriasis, eczema, cellulitis, skin ulcers overlying joints
- Recent joint procedure: Arthrocentesis, injection, arthroscopy, surgery
- IVDU — hematogenous seeding; unusual joint locations
- Age >80
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. |
| Gonococcal NAAT | Urethral/cervical/pharyngeal/rectal NAAT if disseminated gonococcal infection (DGI) suspected. Synovial fluid NAAT increasingly available. |
| X-ray (affected joint) | 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. |
| GNR risk factors (elderly, IVDU, immunocompromised) | 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
- Total duration (native joint): S. aureus: 4 weeks minimum. Streptococcus: 2–3 weeks. GNRs: 3–4 weeks. Gonococcal: 7–14 days.
- 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?
Gonococcal: Young, sexually active. Classic triad: migratory polyarthralgia → tenosynovitis + dermatitis (pustular/vesicular skin lesions) + mono/oligoarthritis. Synovial fluid cultures often NEGATIVE (<25%). Diagnosis: GC NAAT from urethra/cervix/pharynx/rectum + synovial NAAT. Non-gonococcal: Older, comorbidities. Acute monoarthritis. Synovial cultures positive 70–90%. S. aureus predominates.
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
Diagnosis
Arthrocentesis: WBC >50K, >90% PMNs. Gram stain + culture. Blood cultures. Crystals don't rule out infection.
Empiric Therapy
Vancomycin (± ceftriaxone if GNR risk). DGI: ceftriaxone 1g IV daily. De-escalate by culture.
Drainage
Serial aspiration (knee/ankle/wrist). Hip = open arthrotomy always. Arthroscopy if loculated or failing.
Duration
S. aureus: 4 weeks. Strep: 2–3 weeks. GNRs: 3–4 weeks. DGI: 7–14 days. IV → PO step-down supported.
Gonococcal
Young + triad (polyarthralgia, tenosynovitis, pustules). Culture often negative. NAAT from GU/pharynx/rectal. Treat chlamydia too.
Don't Miss
Crystals + infection coexist. Septic hip = surgical emergency. Prosthetic joint = ID + Ortho + long course. RA patients: 10x risk.
📄 One Pager
Septic Arthritis — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
SEPTIC ARTHRITIS — AT A GLANCE
📋 Diagnose: Aspirate every acute monoarthritis. WBC >50K + >90% PMNs = septic. Gram stain + culture.
🧪 Labs: Blood cultures ×2, CRP, ESR. GC NAAT if young/sexually active. X-ray baseline.
💉 Drain: Serial aspiration (knee/ankle). Hip = open arthrotomy ALWAYS. Arthroscopy if failing.
💊 Treat: Vancomycin empirically (± ceftriaxone/cefepime for GNR). DGI: ceftriaxone 1g daily.
⏱️ Duration: Staph 4 wk, Strep 2–3 wk, GNR 3–4 wk, GC 7–14d. IV → PO when improving.
⚠️ Pitfalls: Crystals don't rule out infection. Prosthetic joint = ID + Ortho. RA = 10x risk.
🧪 Labs: Blood cultures ×2, CRP, ESR. GC NAAT if young/sexually active. X-ray baseline.
💉 Drain: Serial aspiration (knee/ankle). Hip = open arthrotomy ALWAYS. Arthroscopy if failing.
💊 Treat: Vancomycin empirically (± ceftriaxone/cefepime for GNR). DGI: ceftriaxone 1g daily.
⏱️ Duration: Staph 4 wk, Strep 2–3 wk, GNR 3–4 wk, GC 7–14d. IV → PO when improving.
⚠️ Pitfalls: Crystals don't rule out infection. Prosthetic joint = ID + Ortho. RA = 10x risk.
High-YieldID / ICU
CLABSI & Line Infections
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.
- Hand hygiene before and after line access
- Maximal barrier precautions at insertion (full drape, cap, mask, sterile gown, sterile gloves)
- 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. |
| Candida suspected (TPN, broad-spectrum abx, immunocompromised) | 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
Diagnosis
Paired cultures: central + peripheral. DTP ≥2h = CRBSI. Two sets CoNS to confirm (not contaminant). Maki tip ≥15 CFU.
Remove Line
ALWAYS for S. aureus, Candida, Pseudomonas. Also: tunnel/port infection, septic shock, endocarditis.
Empiric Therapy
Vancomycin (± cefepime/pip-tazo for GNR risk). Add echinocandin if Candida suspected. De-escalate by culture.
S. aureus BSI
Remove line. TEE mandatory. ID consult. Repeat cultures q24–48h. Min 4 weeks (2 wk only if ALL uncomplicated criteria).
Candidemia
Remove line ≤24h. Echinocandin empiric. Repeat cultures until negative. Ophtho consult. 14 days from first negative cx.
Prevention
Bundle: hand hygiene, max barriers, CHG prep, subclavian preferred, daily line review. Reduces CLABSI 50–70%.
📄 One Pager
CLABSI & Line Infections — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
CLABSI & LINE INFECTIONS — AT A GLANCE
📋 Diagnose: Paired cultures (central + peripheral). DTP ≥2h = line source. ≥2 sets for CoNS.
🔴 Remove line: S. aureus (ALWAYS), Candida (ALWAYS), Pseudomonas, tunnel/port infection, septic shock.
💊 Empiric: Vancomycin ± cefepime/pip-tazo. Add echinocandin if Candida risk.
🔬 S. aureus: Remove line + TEE + ID consult + repeat cultures. Min 4 wk (2 wk if uncomplicated).
🍄 Candida: Remove line ≤24h + echinocandin + ophtho consult. 14d from first negative culture.
🛡️ Prevent: Central line bundle: CHG, max barriers, subclavian preferred, daily line necessity review.
🔴 Remove line: S. aureus (ALWAYS), Candida (ALWAYS), Pseudomonas, tunnel/port infection, septic shock.
💊 Empiric: Vancomycin ± cefepime/pip-tazo. Add echinocandin if Candida risk.
🔬 S. aureus: Remove line + TEE + ID consult + repeat cultures. Min 4 wk (2 wk if uncomplicated).
🍄 Candida: Remove line ≤24h + echinocandin + ophtho consult. 14d from first negative culture.
🛡️ Prevent: Central line bundle: CHG, max barriers, subclavian preferred, daily line necessity review.
High-YieldID / Surgery / Wards
Intra-Abdominal Infections
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 | Uncomplicated appendicitis, uncomplicated cholecystitis, uncomplicated diverticulitis |
| Complicated IAI (cIAI) | Infection extends beyond the organ into the peritoneal space — abscess, peritonitis, or perforation | Perforated appendicitis, perforated diverticulitis, peritonitis, intra-abdominal abscess, anastomotic leak |
| Primary peritonitis (SBP) | Peritoneal infection without visceral perforation. Spontaneous. Almost exclusively in cirrhotics with ascites. | Spontaneous bacterial peritonitis in cirrhosis. Usually monomicrobial (E. coli, Klebsiella, Strep pneumo). |
| Secondary peritonitis | Peritoneal contamination from GI tract perforation or disruption | Perforated ulcer, ruptured appendix, diverticular perforation, anastomotic leak, traumatic bowel injury |
| Tertiary peritonitis | 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. |
| Acute cholangitis | Charcot triad: fever + jaundice + RUQ pain. Reynolds pentad adds AMS + hypotension (severe). Biliary obstruction. | 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. |
| Diverticulitis (complicated) | LLQ pain, fever, perforation/abscess/fistula/stricture. | 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.
- Healthcare-associated/post-surgical: Resistant GNRs (ESBL, Pseudomonas, Acinetobacter), Enterococcus (including VRE), Candida. Broader empiric coverage needed.
- 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. |
| RUQ ultrasound | Cholecystitis, cholangitis, biliary obstruction | First-line for biliary pathology. Gallstones, GB wall thickening (>3 mm), pericholecystic fluid, sonographic Murphy sign, CBD dilation (>6 mm). |
| Blood cultures (×2 sets) | All suspected cIAI, SBP, cholangitis | 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 or Ertapenem 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 or Meropenem 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 or Cefotaxime 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 or Ceftriaxone + 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. |
| Meropenem (Merrem) | Broadest: GNRs (incl ESBL) + anaerobes + Pseudomonas | 1g IV q8h (2g q8h for CNS infections) | 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
Cornerstone of cIAI. Surgery, percutaneous drainage, or ERCP. Antibiotics alone insufficient for undrained collections.
Empiric Therapy
Mild CA: ceftriaxone + metronidazole. Severe: pip-tazo or meropenem. HA: meropenem ± vancomycin ± antifungal.
SBP
PMN ≥250 = SBP. Ceftriaxone + albumin (if renal/liver criteria met). 5 days. Prophylaxis after first episode.
Cholangitis
Charcot triad + Reynolds pentad. ERCP within 24h (emergent if severe). Pip-tazo or ceftriaxone + metronidazole.
Duration
STOP-IT: 4 days after adequate source control. SBP: 5 days. Cholangitis: 4–7 days post-drainage.
Red Flags
Polymicrobial ascites = secondary peritonitis (surgery). Free air = perforation (emergent OR). Lactate rising = inadequate source control.
📄 One Pager
Intra-Abdominal Infections — Quick Reference Card
Print this page (Ctrl/Cmd + P) for a condensed reference card.
INTRA-ABDOMINAL INFECTIONS — AT A GLANCE
🔑 Principle: Source control + antibiotics. Antibiotics alone fail without drainage/surgery.
💊 Mild CA-cIAI: Ceftriaxone + metronidazole, or ertapenem. Severe: pip-tazo or meropenem.
🔬 SBP: PMN ≥250 = treat. Ceftriaxone 2g daily × 5d + albumin. Polymicrobial = secondary peritonitis.
🟡 Cholangitis: Charcot triad → ERCP within 24h. Reynolds pentad = emergent drainage.
⏱️ Duration: STOP-IT: 4 days after adequate source control. Shorter is better.
⚠️ Escalate: HA/post-surgical: meropenem ± vancomycin ± antifungal. De-escalate by culture.
💊 Mild CA-cIAI: Ceftriaxone + metronidazole, or ertapenem. Severe: pip-tazo or meropenem.
🔬 SBP: PMN ≥250 = treat. Ceftriaxone 2g daily × 5d + albumin. Polymicrobial = secondary peritonitis.
🟡 Cholangitis: Charcot triad → ERCP within 24h. Reynolds pentad = emergent drainage.
⏱️ Duration: STOP-IT: 4 days after adequate source control. Shorter is better.
⚠️ Escalate: HA/post-surgical: meropenem ± vancomycin ± antifungal. De-escalate by culture.
VIEW
🩺 Health Check