What is the treatment for a hypertensive crisis?

Treatment of Hypertensive Crisis

For hypertensive emergencies (BP >180/120 mmHg with evidence of target organ damage), immediate intravenous antihypertensive therapy is required with a goal of reducing mean arterial pressure by 20-25% within the first hour, followed by gradual normalization over 24-48 hours. 1, 2

Differentiating Hypertensive Emergency vs. Urgency

Hypertensive Emergency

• Severe BP elevation (>180/120 mmHg) WITH evidence of new/worsening target organ damage
• Examples of target organ damage:
  • Hypertensive encephalopathy
  • Intracranial hemorrhage
  • Acute ischemic stroke
  • Acute myocardial infarction
  • Acute left ventricular failure with pulmonary edema
  • Unstable angina
  • Aortic dissection
  • Acute renal failure
  • Eclampsia
• Requires immediate BP reduction in ICU setting with IV medications
• Untreated 1-year mortality >79% with median survival of only 10.4 months 1, 2

Hypertensive Urgency

• Severe BP elevation WITHOUT acute target organ damage
• Often due to medication non-compliance
• Can be treated with oral antihypertensives
• Does not require emergency department referral or hospitalization 1

Management of Hypertensive Emergency

Setting and Monitoring

• Treat in intensive care unit
• Continuous BP monitoring
• Monitor target organ function

First-Line IV Medications (in order of preference)

1. Nicardipine:

   • Initial: 5 mg/h IV
   • Titration: Increase by 2.5 mg/h every 5 minutes
   • Maximum: 15 mg/h
   • Advantages: No dose adjustment needed for elderly, predictable response 1, 2, 3

2. Clevidipine:

   • Initial: 1-2 mg/h IV
   • Titration: Double dose every 90 seconds initially, then adjust more gradually
   • Maximum: 32 mg/h (maximum duration 72 hours)
   • Contraindicated in patients with soy/egg allergies or lipid metabolism disorders 1, 2

3. Labetalol:

   • 0.3-1.0 mg/kg IV (maximum 20 mg)
   • Repeat every 10 minutes or use 0.4-1.0 mg/kg/h infusion
   • Advantages: Combined alpha and beta blockade
   • Caution: Avoid in patients with heart failure, bradycardia, or bronchospasm 2, 4

4. Sodium Nitroprusside:

   • Initial: 0.3-0.5 mcg/kg/min IV
   • Titration: Increase by 0.5 mcg/kg/min increments
   • Maximum: 10 mcg/kg/min
   • Duration: As short as possible
   • Warning: Risk of cyanide toxicity with prolonged use or high doses; co-administer thiosulfate if infusion rates ≥4 mcg/kg/min or duration >30 minutes
   • Requires intra-arterial BP monitoring 1, 2, 5

Target Blood Pressure Reduction

• General principle: Reduce mean arterial pressure by 20-25% within first hour, then to 160/100 mmHg within 2-6 hours, then cautiously to normal over 24-48 hours 1

• Condition-specific targets 2:

  • Aortic dissection: <120 mmHg systolic within first hour
  • Severe preeclampsia/eclampsia: <140 mmHg systolic within first hour
  • Pheochromocytoma: <140 mmHg systolic within first hour
  • Hypertensive encephalopathy: Reduce MAP by 20-25% immediately
  • Acute ischemic stroke with BP >220/120 mmHg: Reduce MAP by 15% within first hour
  • Acute hemorrhagic stroke with BP >180 mmHg: 130-180 mmHg systolic immediately
  • Acute coronary event: <140 mmHg systolic immediately
  • Cardiogenic pulmonary edema: <140 mmHg systolic immediately

Management of Hypertensive Urgency

• Oral antihypertensive therapy
• First-line agents:
  • ACE inhibitors or ARBs
  • Dihydropyridine calcium channel blockers
  • Beta-blockers
• Reinstitution or intensification of previous antihypertensive regimen
• Treatment of anxiety as applicable

Important Cautions

• Avoid excessive or too rapid BP reduction which could cause cerebral hypoperfusion
• Avoid oral therapy for hypertensive emergencies
• Avoid hydralazine, immediate-release nifedipine, and nitroglycerin as first-line agents due to unpredictable responses and adverse effects 6, 7
• Use sodium nitroprusside with caution due to toxicity concerns 6, 7
• In elderly patients, implement more gradual BP reduction to avoid hypoperfusion
• In patients with malignant hypertension, be aware of potential volume depletion due to pressure natriuresis

Transition to Long-Term Management

• Once BP is stabilized, initiate maintenance therapy
• Consider RAAS inhibitors, calcium channel blockers, or beta-blockers as first-line agents
• Adjust therapy based on comorbidities and underlying causes
• Concomitant longer-acting antihypertensive medication should be administered to minimize duration of IV therapy 5