What is the management of a hypertensive emergency?

Management of Hypertensive Emergency

In hypertensive emergencies, immediate blood pressure reduction with intravenous medications tailored to the specific type of organ damage is essential, with the goal of reducing mean arterial pressure by 20-25% within the first few hours to prevent further organ damage while avoiding excessive drops that could precipitate ischemia. 1

Definition and Recognition

• Hypertensive emergency: Severe BP elevation (typically ≥180/110 mmHg) with evidence of acute target organ damage
• Hypertensive urgency: Severe BP elevation without acute target organ damage

Treatment Algorithm Based on Clinical Presentation

First-Line IV Medications by Clinical Presentation:

Clinical Presentation	Time Frame & Target BP	First-Line Treatment	Alternative
Malignant hypertension with/without TMA or acute renal failure	Several hours, MAP -20% to -25%	Labetalol	Nitroprusside, Nicardipine, Urapidil
Hypertensive encephalopathy	Immediate, MAP -20% to -25%	Labetalol	Nitroprusside, Nicardipine
Acute ischemic stroke and BP >220/120 mmHg	1 hour, MAP -15%	Labetalol	Nitroprusside, Nicardipine
Acute ischemic stroke with indication for thrombolytic therapy and BP >185/110 mmHg	1 hour, MAP -15%	Labetalol	Nicardipine, Nitroprusside
Acute hemorrhagic stroke and SBP >180 mmHg	Immediate, SBP 130-180 mmHg	Labetalol	Urapidil, Nicardipine
Acute coronary event	Immediate, SBP <140 mmHg	Nitroglycerin	Urapidil, Labetalol
Acute cardiogenic pulmonary edema	Immediate, SBP <140 mmHg	Nitroprusside or Nitroglycerin (with loop diuretic)	Urapidil (with loop diuretic)
Acute aortic disease	Immediate, SBP <120 mmHg and HR <60 bpm	Esmolol and Nitroprusside or Nitroglycerin	Labetalol or Metoprolol, Nicardipine

IV Medication Administration Guidelines

Labetalol (First-line for most presentations)

• Administer by slow continuous infusion via central line or large peripheral vein
• Initial rate: 5 mg/hr
• Titration: Increase by 2.5 mg/hr every 15 minutes
• Maximum dose: 15 mg/hr 1, 2
• Mechanism: Combined alpha and beta blockade
• Caution: Avoid in patients with severe bradycardia, heart block, or decompensated heart failure 2

Nicardipine

• Administer by slow continuous infusion via central line or large peripheral vein
• Concentration: 0.1 mg/mL (dilute 25 mg in 240 mL of compatible IV fluid)
• Compatible with: Dextrose 5%, Normal saline 0.9%, combinations of these
• Not compatible with: Sodium bicarbonate 5%, Lactated Ringer's
• Initial rate: 5 mg/hr
• Titration: Increase by 2.5 mg/hr every 5-15 minutes based on urgency
• Maximum rate: 15 mg/hr 3
• Change infusion site every 12 hours if administered via peripheral vein

Nitroglycerin (For acute coronary events or pulmonary edema)

• Initial bolus: 20 mg IV over 2 minutes
• Follow with: 20-80 mg boluses every 10 minutes as needed
• Maximum cumulative dose: 300 mg 1

Management of Volume Overload in Hypertensive Emergency

IV Loop Diuretics

• First-line therapy for acute pulmonary edema with volume overload
• Initial dose: Higher than patient's usual oral dose (consider 80-120mg furosemide)
• Continuous infusion more effective than bolus dosing in resistant cases 1

Ultrafiltration Considerations

• Consider for patients with evident volume overload not responding to diuretics
• Initiate rate conservatively and increase gradually
• Goal: Reduce mean arterial pressure by 20-25% in first hours
• Requires consultation with nephrologist and adequate vascular access 1

Monitoring Protocol

• Continuous monitoring of vital signs
• Check BP every 30 minutes during first 2 hours
• Assess BUN and creatinine within 2-4 hours
• Monitor urine output and electrolytes (particularly potassium) regularly
• Consider invasive hemodynamic monitoring in severe cases 1

Important Cautions

• Too rapid BP reduction can lead to cerebral, coronary, or renal ischemia
• Avoid sodium nitroprusside when possible due to toxicity concerns
• Avoid short-acting nifedipine, hydralazine, and nitroglycerin as first-line agents due to unpredictable responses 1
• When positioning patients, consider postural hypotension effects due to alpha-blocking medications 2

Transition to Oral Therapy

• Initial oral therapy should include an ACE inhibitor or ARB plus a dihydropyridine calcium channel blocker or thiazide/thiazide-like diuretic
• Preferably use fixed-dose combination in a single pill 1
• When switching from IV to oral therapy, administer first oral dose 1 hour prior to discontinuation of the infusion