What is the treatment for a hypertensive emergency?

Treatment of Hypertensive Emergency

Immediate Management and Blood Pressure Goals

Admit patients with hypertensive emergencies to an intensive care unit and initiate continuous intravenous antihypertensive therapy with the goal of reducing mean arterial pressure by no more than 25% within the first hour. 1

Standard Blood Pressure Reduction Protocol

• First hour: Reduce mean arterial pressure by 25% maximum 1, 2
• Next 2-6 hours: Further reduce to 160/100-110 mmHg if the patient remains stable 1, 2
• Following 24-48 hours: Gradually normalize blood pressure toward baseline 1, 2

Special Clinical Situations Requiring Modified Targets

Different hypertensive emergencies require specific blood pressure targets and timelines 1:

Acute aortic dissection:

• Most aggressive reduction needed: SBP <120 mmHg within 1 hour 1, 2
• Must also reduce heart rate to <60 bpm 1
• Use beta-blockers as first-line agents 2

Acute coronary syndrome or cardiogenic pulmonary edema:

• Target SBP <140 mmHg immediately 1
• Nitroglycerin is particularly indicated for these presentations 2

Acute hemorrhagic stroke:

• Target 130 < SBP < 180 mmHg immediately 1

Acute ischemic stroke:

• If SBP >220 mmHg or DBP >120 mmHg: reduce MAP by 15% over 1 hour 1
• If thrombolytic therapy planned and SBP >185 mmHg or DBP >110 mmHg: reduce MAP by 15% over 1 hour 1

Eclampsia/severe preeclampsia:

• Target SBP <160 mmHg and DBP <105 mmHg immediately 1, 2

Malignant hypertension with or without thrombotic microangiopathy:

• Reduce MAP by 20-25% over several hours 1, 2

Hypertensive encephalopathy:

• Reduce MAP by 20-25% immediately 1, 2

First-Line Intravenous Antihypertensive Agents

Preferred Medications

Nicardipine (5-15 mg/hr IV):

• Recommended as first-line therapy alongside labetalol 2
• Start at 5 mg/hr and increase by 2.5 mg/hr every 15 minutes (for gradual reduction) or every 5 minutes (for rapid reduction) up to maximum 15 mg/hr 3
• Particularly useful for most hypertensive emergencies without specific contraindications 1
• Avoid in acute coronary ischemia 2

Labetalol:

• Recommended as first-line therapy alongside nicardipine 2
• Especially indicated for aortic dissection due to beta-blocking properties 2
• Effective for malignant hypertension and hypertensive encephalopathy 2

Clevidipine:

• Newer agent with potential advantages over traditional therapies 4
• Ultra-short-acting dihydropyridine calcium channel blocker 5
• Provides precise titration control 6

Fenoldopam (0.1-0.3 μg/kg/min IV):

• Selective dopamine-1 receptor agonist 2
• May offer advantages over traditional agents 4
• Contraindicated in glaucoma 2

Alternative Agents

Nitroglycerin (5-100 μg/min IV):

• Specifically indicated for acute coronary syndrome and cardiogenic pulmonary edema 2
• Should not be considered first-line for general hypertensive emergencies 4

Sodium nitroprusside (0.25-10 μg/kg/min IV):

• Extremely rapid onset and offset 7
• Should be avoided due to significant toxicity risk (cyanide and thiocyanate toxicity) 2, 4, 5
• If used, avoid in patients with elevated intracranial pressure or azotemia 2

Critical Pitfalls to Avoid

Excessive blood pressure reduction:

• Too rapid or excessive lowering causes cerebral, coronary, or renal hypoperfusion 1, 2
• This is the most dangerous complication of treatment 1

Inappropriate medication selection:

• Never use short-acting nifedipine due to uncontrolled blood pressure reduction risk 1, 2
• Avoid hydralazine and immediate-release nifedipine as first-line agents 4, 5
• Sodium nitroprusside should be avoided whenever possible due to toxicity 4, 5

Failure to consider baseline blood pressure:

• Patients with chronic hypertension may not tolerate "normal" blood pressure ranges 2
• Assess volume status to avoid depletion 2

Monitoring Requirements

Continuous monitoring in ICU setting:

• Intra-arterial blood pressure monitoring preferred 1
• Continuous cardiac monitoring 1
• Frequent neurologic assessments 1

Change peripheral IV sites every 12 hours if not using central access 3

Transition to Oral Therapy

• Initiate oral antihypertensive therapy after 6-12 hours of stable parenteral therapy 8
• When switching to oral nicardipine, administer first dose 1 hour prior to discontinuing IV infusion 3
• Continue follow-up for underlying hypertension management 1
• Evaluate for secondary causes of hypertension after ICU transfer 8