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 (reflex tachycardia worsens shear stress), CAD (unpredictable response, reflex tachycardia), elevated ICP |
Related Topics
Acute Decompensated Heart FailureAcute Exacerbation of COPD (AECOPD)Acute Ischemic StrokeAcute Mesenteric IschemiaAcute PancreatitisAirway & Ventilator Management
🧪 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.
| Test | Looking For | End-Organ Damage |
|---|---|---|
| BMP + Cr | Cr above baseline | Renal: AKI from malignant nephrosclerosis |
| UA + microscopy | Proteinuria, hematuria, RBC casts | Renal: Active sediment = hypertensive nephropathy |
| Troponin | Elevated, rise-fall | Cardiac: Demand ischemia or ACS from afterload |
| ECG | LVH, ST/T changes, new arrhythmia | Cardiac: Acute ischemia, atrial strain |
| CXR | Pulmonary edema, wide mediastinum | Cardiac: Flash pulmonary edema. Wide mediastinum → CTA for dissection |
| Fundoscopy | Flame hemorrhages, papilledema | Retinal/CNS: Grade III-IV = malignant HTN |
| CT head | Hemorrhage, PRES, ischemia | CNS: Order if headache, AMS, focal deficits, seizures, visual changes |
| Peripheral smear | Schistocytes, low platelets | Hematologic: MAHA from shear stress. Check LDH ↑, haptoglobin ↓ |
| BNP | Elevated | Cardiac: Flash pulmonary edema from afterload crisis |
| Urine drug screen | Cocaine, amphetamines | Etiology: Avoid beta-blockers with cocaine (unopposed alpha) |
| Pregnancy test | Positive β-hCG | Etiology: Pre-eclampsia/eclampsia → magnesium + delivery |
Emergency vs Urgency: Emergency = elevated BP + end-organ damage → IV meds, ICU, reduce MAP 25% in first hour. Urgency = elevated BP WITHOUT damage → oral meds, discharge with follow-up 24-72h. Do NOT use IV meds for urgency.
📋 On Rounds
On Rounds
Pimp Questions
Why should you not lower BP too fast in hypertensive emergency?
Chronic hypertension shifts the cerebral autoregulation curve rightward. These patients need higher perfusion pressures to maintain cerebral blood flow. Rapid BP reduction causes cerebral ischemia -watershed infarcts, blindness (anterior ischemic optic neuropathy), renal infarction. Max 25% MAP reduction in first hour.
What is the BP target for ischemic stroke and why is it different?
Only treat if BP > 220/120 (no tPA) because elevated BP in ischemic stroke maintains perfusion to the ischemic penumbra. Lowering BP aggressively expands the infarct. Exception: if patient is a tPA candidate, reduce to < 185/110 first to reduce hemorrhage risk.
Why do you target only 25% MAP reduction in the first hour instead of normalizing BP?
Cerebral autoregulation is shifted right in chronic hypertension. The brain has adapted to higher pressures -the autoregulatory curve (which maintains constant cerebral blood flow across a range of MAPs) shifts upward. If you drop BP too quickly to "normal" levels, you fall below the lower limit of autoregulation → cerebral hypoperfusion → watershed stroke.
What IV antihypertensive do you choose for different end-organ emergencies?
Match the drug to the complication: Nicardipine (DHP CCB drip): best all-purpose -works for most emergencies. Smooth, titratable, no CNS depression. Clevidipine: ultra-short acting CCB -good when minute-to-minute control needed. Labetalol: combined α/β blocker -good for aortic dissection (reduces HR + BP), preeclampsia (safe in pregnancy). Esmolol: ultra-short BB -best for dissection when you need rapid HR < 60.
Clinical Examples
📋 Case 1, Hypertensive Emergency with Acute Kidney Injury
Patient: 54M, non-adherent to amlodipine and lisinopril, presents with headache, blurred vision, and nausea. No chest pain or focal neurologic deficits.
Key findings: BP 238/142, HR 92. Fundoscopy: flame hemorrhages + papilledema. Cr 3.4 (baseline 1.2), proteinuria 3+, hematuria. CT head negative. TTE: LVH, EF 55%.
Management:
- IV nicardipine drip starting at 5 mg/hr, titrate q5-15 min (max 15 mg/hr)
- Target: reduce MAP by 25% in first hour, then to 160/100 over next 2-6h
- Arterial line for continuous BP monitoring
- Trending Cr q12h, expect improvement with controlled BP reduction
- Transition to oral amlodipine 10 mg + lisinopril 20 mg when stable on drip x 24h
Teaching point: Hypertensive nephrosclerosis with acute end-organ damage (AKI + papilledema) defines hypertensive emergency. Nicardipine is first-line for most hypertensive emergencies: smooth, titratable, no CNS depression. Renal function often improves with controlled BP reduction.
📋 Case 2, Hypertensive Emergency in Acute Ischemic Stroke
Patient: 72F, HTN and AF (not on anticoagulation), presents with acute right-sided weakness and aphasia. Symptom onset 2 hours ago. NIHSS 14.
Key findings: BP 204/118, HR 88 irregular. CT head: no hemorrhage. CTA: left MCA occlusion. tPA candidate (within window, no contraindications).
Management:
- BP must be < 185/110 BEFORE tPA administration
- IV labetalol 10-20 mg bolus; repeat if needed. Alternatively, nicardipine drip
- Once tPA given: maintain BP < 180/105 for 24 hours
- If NOT a tPA candidate: only treat BP if > 220/120 (permissive hypertension protects the penumbra)
- Thrombectomy evaluation given large vessel occlusion
Teaching point: BP management in stroke differs from other hypertensive emergencies. Aggressive BP lowering in ischemic stroke expands the infarct by reducing perfusion to the penumbra. The only reason to lower BP acutely is to safely give tPA. AHA/ASA Stroke Guidelines, 2019
📋 Case 3, Pheochromocytoma Crisis
Patient: 42F, no prior medical history, presents with episodic severe headaches, palpitations, and diaphoresis. In the ED, BP spikes to 260/150 with HR 132 during a paroxysm.
Key findings: Between episodes: BP 145/90. 24h urine metanephrines: 4x upper normal. CT abdomen: 4.2 cm right adrenal mass. Plasma-free metanephrines markedly elevated.
Management:
- Phentolamine 5 mg IV bolus for acute crisis (alpha-blocker)
- Start phenoxybenzamine 10 mg BID, titrate up over 10-14 days pre-operatively
- Add beta-blocker (propranolol) ONLY AFTER adequate alpha blockade (typically 3-5 days later)
- NEVER give beta-blocker first, causes unopposed alpha stimulation and hypertensive crisis
- High-sodium diet + liberal fluids to restore intravascular volume before surgery
Teaching point: Pheochromocytoma hypertensive crisis requires alpha-blockade FIRST. Beta-blockers before alpha-blockade removes the beta-2 vasodilatory counterbalance, leaving unopposed alpha vasoconstriction. This is one of the most testable concepts in medicine.
📋 Sample Presentation
"Mrs. Okafor is a 58-year-old with poorly controlled hypertension who presented with BP 210/130, severe headache, and confusion. She was found to have papilledema on fundoscopy and elevated creatinine of 2.8 from a baseline of 1.0, consistent with hypertensive emergency with end-organ damage involving the CNS and kidneys. CT head showed no hemorrhage. She was started on nicardipine drip and MAP was reduced by 22% over the first hour to 147. She is now alert, BP 158/96 on nicardipine 8 mg/hr. Plan is to continue gradual reduction to target BP 150/90 over the next 24–48 hours, then transition to oral agents."
Monitoring Parameters -Hypertensive Emergency
| Parameter | Frequency | Target / Action |
|---|---|---|
| Arterial line BP | Continuous (art line mandatory in ICU) | Reduce MAP no more than 25% in the first hour. Cuff pressures are insufficient for IV drip titration -art line is standard of care. |
| MAP during titration | q5–15 min while adjusting IV drip | First hour: ≤ 25% MAP reduction. Next 2–6h: target ~160/100. Next 24–48h: gradual normalization. Too fast → watershed stroke. |
| Neuro checks | q1–2h during active titration | GCS, pupil reactivity, focal deficits, level of consciousness. New deficit during BP lowering → stop titration, allow BP to rise, urgent imaging (stroke?). |
| Urine output | q1h (Foley) | UOP ≥ 0.5 mL/kg/hr. Declining UOP during BP reduction = renal hypoperfusion -may need to allow higher BP target. |
| Creatinine | q12–24h | Trend from baseline. Rising Cr suggests renal end-organ injury or overly aggressive BP lowering. Adjust target accordingly. |
| Troponin | On admission, repeat at 6h if elevated or ongoing chest pain | Hypertensive emergency can cause demand ischemia (type 2 MI). Elevated troponin changes management -cardiology consult. |
| Fundoscopic exam | On admission, repeat if worsening | Papilledema, flame hemorrhages, cotton-wool spots, AV nicking. Presence confirms end-organ damage and classifies as true emergency vs urgency. |
| Transition to oral agents | After 12–24h stable on IV drip | Start long-acting oral antihypertensives (amlodipine, lisinopril, etc.) with IV drip overlap. Wean drip gradually as oral agents take effect (24–48h). Do not abruptly stop IV. |
BP reduction timeline: 25% MAP reduction in first hour → 160/100 over next 2–6h → gradual normalization over 24–48h. Exception: aortic dissection -target SBP < 120 + HR < 60 within minutes (esmolol + nicardipine). Exception: ischemic stroke -do NOT lower BP unless > 220/120 (or > 185/110 if tPA candidate).
⚡ Summary
Summary
The Number Does Not Define It
Hypertensive emergency is severe hypertension with acute end-organ damage; urgency is the same number without it. The workup answers one question: is there end-organ damage? Yes means IV therapy and monitored care; no means oral therapy and outpatient follow-up. Treating a high number in an asymptomatic patient causes harm.
Look for the Damage Systematically
Brain: encephalopathy, stroke, PRES. Heart: ACS, acute pulmonary edema, aortic dissection. Kidney: acute kidney injury, hematuria and proteinuria. Eye: retinal hemorrhages, exudates, papilledema. Blood: microangiopathic hemolysis. Fundoscopy is quick, free and frequently omitted.
Lower It Slowly, With Two Exceptions
Reduce the mean arterial pressure by no more than 25% in the first hour, then toward 160/100 over the next 2 to 6 h. Cerebral autoregulation is shifted rightward in chronic hypertension, so a rapid drop causes watershed infarction, blindness and renal failure. Aortic dissection is the aggressive exception; ischemic stroke is the conservative one.
Exclude Dissection Before Choosing a Drug
Severe hypertension with chest or back pain means CT angiography of the chest, abdomen and pelvis immediately. Target a systolic of 100 to 120 and a heart rate below 60 within 20 minutes, using a beta blocker FIRST (esmolol or labetalol), then a vasodilator. Do not give nitroprusside or any vasodilator before rate control: reflex tachycardia increases aortic wall shear stress and extends the dissection.
Match the Drug to the Organ
Nicardipine or clevidipine for most emergencies, including neurologic ones, because they are titratable and do not raise intracranial pressure. Labetalol for stroke and dissection. Nitroglycerin for pulmonary edema and ACS. Hydralazine or labetalol for preeclampsia. Phentolamine for pheochromocytoma and cocaine.
Never Beta-Block Alone in Catecholamine Excess
In pheochromocytoma, beta blockade without prior alpha blockade leaves unopposed alpha stimulation and precipitates a paradoxical hypertensive crisis. The same principle applies in cocaine and amphetamine toxicity, where benzodiazepines, nitrates and phentolamine are the appropriate agents.
Use an Arterial Line and an Infusion, Not Boluses
Titratable infusions with continuous monitoring, because intermittent boluses produce the overshoot that causes the ischemic complications. Avoid sublingual nifedipine entirely: it drops the pressure precipitously and unpredictably and has caused strokes and infarcts.
Find the Reason It Got This High
Non-adherence and abrupt withdrawal of clonidine or a beta blocker are the commonest causes, and clonidine withdrawal produces a rebound crisis that needs the drug restarted rather than a new one added. Also screen for renal artery stenosis, primary aldosteronism, pheochromocytoma, thyroid disease, sleep apnea, cocaine and sympathomimetics, and NSAIDs. Discharge with a regimen the patient can actually afford and take, plus follow-up within days.
📄 One Pager
Text version
ICU · One Pager
Hypertensive Emergency
End-organ damage defines the emergency. The organ being damaged determines the drug and the target. Never drop BP > 25% in first hour.
Exclude First -Aortic Dissection
- Chest/back pain + very high BP → CTA chest/abdomen NOW
- Target SBP < 120, HR < 60 ASAP
- Esmolol + nicardipine or nitroprusside
- Never nitrates alone (reflex tachycardia)
BP Reduction Rule
- Reduce MAP ≤ 25% in first hour
- Then to 160/100 over 2–6h
- Exception: Dissection (aggressive) and ischemic stroke (conservative)
- Ischemic stroke: only treat if BP > 220/120
Drug by Syndrome
Most emergenciesNicardipine 5–15 mg/hr IV
Aortic dissectionEsmolol + nicardipine
ACS / pulmonary edemaNitroglycerin IV + labetalol
Stroke (hemorrhagic)Nicardipine → SBP < 140
EclampsiaLabetalol IV + MgSO₄
PheochromocytomaPhentolamine (α first!) then β-blocker
Pheo Rule
- α-block FIRST with phentolamine
- THEN add beta-blocker
- Beta-block first → unopposed α → crisis
Why Not Too Fast?
- Chronic HT shifts autoregulation rightward
- Rapid drop → cerebral ischemia
- Watershed infarcts, blindness, renal infarction