What is the management of a hypertensive emergency?

From the Guidelines

Hypertensive emergency is a severe elevation in blood pressure (typically >180/120 mmHg) with evidence of acute end-organ damage requiring immediate treatment with intravenous antihypertensive medications to reduce blood pressure by no more than 25% within the first hour, then to 160/100-110 mmHg within the next 2-6 hours, avoiding excessive drops that could worsen organ perfusion, as recommended by the 2020 international society of hypertension global hypertension practice guidelines 1.

Key Considerations

• The choice of antihypertensive treatment is predominantly determined by the type of organ damage, with specific clinical presentations of hypertensive emergencies including malignant hypertension, hypertensive encephalopathy, hypertensive thrombotic microangiopathy, and other conditions such as cerebral hemorrhage, acute stroke, acute coronary syndrome, cardiogenic pulmonary edema, aortic aneurysm/dissection, and severe preeclampsia and eclampsia 1.
• First-line medications include nicardipine, labetalol, or clevidipine, with additional medications indicated for specific conditions, such as sodium nitroprusside for aortic dissection, nitroglycerin for acute coronary syndrome, or furosemide for pulmonary edema 1.
• The urgency of treatment stems from preventing further damage to vital organs, including the brain, heart, kidneys, and eyes, as sustained severe hypertension can lead to stroke, myocardial infarction, acute kidney injury, or vision loss 1.

Management Approach

• Initial treatment involves intravenous antihypertensive medications, with the goal of reducing blood pressure by no more than 25% within the first hour, then to 160/100-110 mmHg within the next 2-6 hours, avoiding excessive drops that could worsen organ perfusion 1.
• Once stabilized, transition to oral antihypertensives should begin, typically with multiple agents addressing different pathways, as recommended by the 2017 acc/aha/aapa/abc/acpm/ags/apha/ash/aspc/nma/pcna guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.

Specific Conditions

• For acute aortic dissection, esmolol or labetalol are preferred, with the goal of reducing systolic blood pressure to ≤120 mm Hg within 20 minutes, as recommended by the 2017 acc/aha/aapa/abc/acpm/ags/apha/ash/aspc/nma/pcna guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.
• For acute coronary syndromes, esmolol, labetalol, nicardipine, or nitroglycerin may be used, with caution in patients with contraindications to beta blockers, such as moderate-to-severe LV failure with pulmonary edema, bradycardia, hypotension, poor peripheral perfusion, second- or third-degree heart block, and reactive airways disease 1.

From the FDA Drug Label

For more rapid blood pressure reduction, titrate every 5 minutes. Titration For a gradual reduction in blood pressure, initiate therapy at a rate of 5 mg/hr. If desired blood pressure reduction is not achieved at this dose, increase the infusion rate by 2. 5 mg/hr every 15 minutes up to a maximum of 15 mg/hr, until desired blood pressure reduction is achieved.

• Hypertensive emergency treatment with nicardipine (IV) involves titrating the infusion rate every 5 minutes for more rapid blood pressure reduction, starting at 5 mg/hr and increasing by 2.5 mg/hr every 15 minutes up to a maximum of 15 mg/hr 2.
• Clevidipine (IV) is also used for blood pressure reduction, with an estimated infusion rate of approximately 10 mg/hour necessary to achieve half of the maximal effect 3.
• The choice of nicardipine (IV) or clevidipine (IV) for hypertensive emergency depends on the clinical situation and the patient's response to treatment.
• It is essential to closely monitor the patient's blood pressure and adjust the infusion rate accordingly to avoid hypotension or tachycardia.

From the Research

Definition and Classification of Hypertensive Emergency

• Hypertensive crises are categorized as hypertensive emergencies or urgencies, depending on the presence of acute target-organ damage 4, 5, 6.
• Hypertensive emergencies are potentially life-threatening medical conditions that require urgent treatment under close monitoring 5.
• Approximately 1% of patients with hypertension will, at some point, develop a hypertensive crisis 4.

Treatment of Hypertensive Emergency

• Immediate reduction in blood pressure is required only in patients with acute end-organ damage (i.e., hypertensive emergency) and requires treatment with a titratable, short-acting, intravenous antihypertensive agent 4, 7, 6.
• Rapid-acting intravenous antihypertensive agents are available, including labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside 4, 7.
• Newer agents, such as clevidipine, may hold considerable advantages over other available agents in the management of hypertensive crises 4, 5, 8.
• The selection of a specific agent should be based on the agent's pharmacology and patient-specific factors, such as comorbidity and the presence of end-organ damage 7.

Pharmacological Management

• Clevidipine, a third-generation dihydropyridine calcium-channel blocker, has unique pharmacodynamic and pharmacokinetic properties and has been shown to reduce mortality when compared with nitroprusside 5, 8.
• Clevidipine is effective in the treatment of both acute preoperative and postoperative hypertension in adult cardiac surgery patients, and has a rapid onset and short duration of action, allowing for easy titration for predictable blood pressure control 8.
• The drug is generally well tolerated, with a safety profile similar to that of sodium nitroprusside, nitroglycerin, or nicardipine in cardiac surgery patients 8.