What is the first line treatment for a hypertensive crisis?

First-Line Treatment for Hypertensive Crisis

For hypertensive emergencies, intravenous labetalol is the recommended first-line treatment for most clinical presentations. 1

Understanding Hypertensive Crisis

• Hypertensive crisis is defined as severe blood pressure elevation (>180/120 mmHg) and is categorized into two types 1:

  • Hypertensive emergency: Severe BP elevation with evidence of new or worsening target organ damage
  • Hypertensive urgency: Severe BP elevation without acute end-organ damage

• Untreated hypertensive emergencies have a 1-year mortality rate >79% with median survival of only 10.4 months 1

First-Line Treatment Algorithm for Hypertensive Emergencies

1. Immediate intravenous therapy is required for hypertensive emergencies 1

2. First-line medication by condition:

   • Malignant hypertension/hypertensive encephalopathy: Labetalol IV (initial 0.3-1.0 mg/kg dose, maximum 20 mg slow IV injection every 10 min) 1
   • Acute ischemic stroke: Labetalol IV (when BP >220/120 mmHg or with thrombolytic therapy when BP >185/110 mmHg) 1
   • Acute hemorrhagic stroke: Labetalol IV (for systolic BP >180 mmHg) 1
   • Eclampsia/pre-eclampsia: Labetalol IV or nicardipine with magnesium sulfate 1
   • Acute coronary events: Nitroglycerin (first-line), with labetalol as alternative 1
   • Acute pulmonary edema: Nitroprusside or nitroglycerin with loop diuretic 1
   • Acute aortic dissection: Esmolol and nitroprusside/nitroglycerin (target SBP <120 mmHg and heart rate <60 bpm) 1

3. BP reduction targets:

   • Reduce mean arterial pressure by 20-25% within first hour 1
   • Then, if stable, reduce to 160/100 mmHg within next 2-6 hours 1
   • Cautiously normalize BP over following 24-48 hours 1

Alternative First-Line Agents

• Nicardipine IV: Initial 5 mg/h, increasing every 5 min by 2.5 mg/h to maximum 15 mg/h 1
• Clevidipine IV: Initial 1-2 mg/h, doubling every 90 seconds until BP approaches target 1
• Sodium nitroprusside IV: Indicated for immediate BP reduction in hypertensive crises 2, but should be used with caution due to risk of cyanide toxicity with prolonged use 1, 3

Special Considerations

• For cocaine/amphetamine-induced hypertensive crisis, benzodiazepines should be administered first, followed by phentolamine, nicardipine, or nitroprusside if needed 1
• For pheochromocytoma-induced crisis, phentolamine, nitroprusside, or urapidil are preferred; labetalol may worsen hypertension in some cases 1
• Beta-blockers (including labetalol) are relatively contraindicated in patients with reactive airway disease or COPD 1

Treatment of Hypertensive Urgency

• Oral medications with close monitoring are appropriate 4
• Avoid rapid, uncontrolled BP reduction 4, 5
• Observe for at least 2 hours after initiating or adjusting medication 4

Monitoring and Follow-up

• Intra-arterial BP monitoring is recommended for patients receiving nitroprusside to prevent "overshoot" 1
• Patients with previous hypertensive emergencies remain at increased risk for cardiovascular and renal disease 1
• Frequent follow-up (at least monthly) in a specialized setting is recommended until target BP is reached 1

Common Pitfalls to Avoid

• Excessive BP reduction may precipitate renal, cerebral, or coronary ischemia 4, 5
• Short-acting nifedipine should NOT be used due to risk of uncontrolled BP falls 4, 3
• Sodium nitroprusside should be used with caution due to toxicity concerns 3, 5