What is the treatment for hypertension in the emergency room (ER)?

Treatment for Hypertension in the ER

Critical First Step: Distinguish Emergency from Urgency

The most important decision in the ER is determining whether acute target organ damage is present—this distinction completely changes management. 1, 2

Hypertensive Emergency (BP >180/120 mmHg WITH acute organ damage)

• Admit to ICU immediately for continuous BP monitoring and IV antihypertensive therapy 1, 2
• Requires parenteral medications with rapid onset and short duration 1, 3
• The absolute BP number matters less than the presence of acute end-organ damage 1, 4

Hypertensive Urgency (BP >180/120 mmHg WITHOUT organ damage)

• Do NOT rapidly lower BP in the ER—this is unnecessary and potentially harmful 1
• Initiate or restart oral long-acting antihypertensives and arrange outpatient follow-up 1, 5
• Up to one-third of these patients normalize BP before follow-up without acute intervention 1

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Blood Pressure Reduction Goals

For Patients WITHOUT Compelling Conditions

Reduce systolic BP by no more than 25% within the first hour 1, 2, 3

• Then, if stable, target 160/100 mmHg within the next 2-6 hours 1, 2
• Cautiously normalize over the following 24-48 hours 1, 3
• Avoid excessive reductions—drops >50% in mean arterial pressure are associated with ischemic stroke and death 3

For Patients WITH Compelling Conditions

More aggressive reduction to SBP <140 mmHg within the first hour 1

• Aortic dissection: Target SBP <120 mmHg 1
• Severe preeclampsia/eclampsia: Target SBP <140 mmHg 1
• Pheochromocytoma crisis: Target SBP <140 mmHg 1

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First-Line IV Medications

Nicardipine (Preferred for Most Cases)

Nicardipine and labetalol are the most commonly used first-line agents and should be available in all EDs 2, 3

• Start at 5 mg/hr, increase by 2.5 mg/hr every 5 minutes to maximum 15 mg/hr 1, 3, 6
• For more rapid control, titrate every 5 minutes 6
• Potent arteriolar vasodilator without significant myocardial depression 7
• Avoid in severe aortic stenosis 7

Labetalol (Alternative First-Line)

• Initial bolus: 20 mg IV over 2 minutes 3, 8
• Repeat 20-80 mg every 10 minutes up to total cumulative dose of 300 mg 1, 3
• Alternative: continuous infusion 0.4-1.0 mg/kg/hr up to 3 mg/kg/hr 1
• Combined alpha- and beta-blockade provides BP reduction without reflex tachycardia 8

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Condition-Specific Treatment

Acute Coronary Syndrome

Start with IV nitroglycerin 2, 3

• Initial 5 mcg/min, increase by 5 mcg/min every 3-5 minutes to maximum 20 mcg/min 1
• Particularly useful in patients with coronary ischemia 2, 3

Acute Pulmonary Edema

Use sodium nitroprusside or nitroglycerin 3

• Nitroprusside: Start 0.3-0.5 mcg/kg/min, increase by 0.5 mcg/kg/min increments to maximum 10 mcg/kg/min 1, 3
• Keep duration as short as possible—risk of cyanide toxicity with prolonged use or rates ≥4 mcg/kg/min 1, 3

Aortic Dissection

Combine esmolol with nitroprusside or nitroglycerin 3

• Esmolol loading dose: 500-1000 mcg/kg/min over 1 minute, then 50 mcg/kg/min infusion 1
• Target heart rate reduction before vasodilation to prevent shear stress 3

Hypertensive Encephalopathy

Labetalol is the initial treatment of choice 2, 3

• Use standard labetalol dosing as above 1, 3

Acute Stroke

• Ischemic stroke with BP >220/120 mmHg: Use labetalol 3
• Hemorrhagic stroke with SBP >180 mmHg: Use labetalol 3
• Exercise caution—excessive BP lowering can worsen cerebral perfusion 3

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Critical Monitoring Requirements

Continuous intra-arterial BP monitoring is ideal for all hypertensive emergencies 2, 3

• Monitor cardiac, neurological, and renal function continuously 2
• If using peripheral IV for nicardipine, change infusion site every 12 hours 6
• Adjust infusion rates based on response—do not expect normalization during initial ED visit 1

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Medications to AVOID

Never use immediate-release nifedipine for hypertensive emergencies 3, 4

• Associated with unpredictable and excessive BP drops 4
• No longer acceptable for initial treatment 3

Use sodium nitroprusside with extreme caution 4

• Risk of cyanide toxicity limits its use 1, 4
• Reserve for specific situations like acute pulmonary edema 3

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Common Pitfalls

• Do not treat asymptomatic severe hypertension aggressively in the ER—this causes more harm than benefit 1
• Do not normalize BP during the initial ED visit—gradual reduction over 24-48 hours prevents ischemic complications 1
• Do not use oral therapy for true hypertensive emergencies—parenteral agents are required 1
• Do not allow patients to stand unmonitored—postural hypotension is common with labetalol 8