What is the management of hypertensive emergency (severe hypertension)?

From the Guidelines

Management of hypertensive emergency requires immediate blood pressure reduction to prevent end-organ damage, with the goal of reducing mean arterial pressure by 20-25% within the first hour, then gradually to 160/100-110 mmHg over the next 2-6 hours, as recommended by the most recent 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, and acute coronary event 1.
• First-line medications include labetalol, nicardipine, or clevidipine, with nitroprusside being effective but requiring careful monitoring due to cyanide toxicity risk with prolonged use 1.
• For patients with specific conditions, use esmolol for aortic dissection, nitroglycerin for acute coronary syndromes, and hydralazine or labetalol for preeclampsia 1.

Monitoring and Management

• Regular vital sign monitoring, neurological checks, and assessment of urine output help track response to treatment and prevent complications 1.
• Concurrent management of complications like pulmonary edema, acute kidney injury, or neurological deficits is essential, with additional investigations required depending on presentation and clinical findings 1.
• Secondary causes can be found in 20%–40% of patients presenting with malignant hypertension, and appropriate diagnostic workup to confirm or exclude secondary forms is indicated 1.

Treatment Approach

• Begin with IV antihypertensive medications in a monitored setting, aiming for a controlled reduction of blood pressure, with the specific medication and dosage determined by the patient's condition and response to treatment 1.
• Avoid rapid blood pressure reduction, which can cause cerebral, renal, or coronary hypoperfusion, and transition to oral antihypertensives once stabilized 1.

From the FDA Drug Label

The time course of blood pressure decrease is dependent on the initial rate of infusion and the frequency of dosage adjustment. Nicardipine hydrochloride injection is administered by slow continuous infusion at a concentration of 0. 1 mg/mL. With constant infusion, blood pressure begins to fall within minutes. It reaches about 50% of its ultimate decrease in about 45 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. For more rapid blood pressure reduction, titrate every 5 minutes. In patients with severe or postoperative hypertension, nicardipine hydrochloride injection (5 to 15 mg/hr) produced dose-dependent decreases in blood pressure. Higher infusion rates produced therapeutic responses more rapidly

The management of hypertensive emergency with nicardipine (IV) involves:

• Initiating therapy at a rate of 5 mg/hr for a gradual reduction in blood pressure
• Increasing 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
• Titrating every 5 minutes for more rapid blood pressure reduction
• Monitoring closely when titrating nicardipine hydrochloride injection in patients with congestive heart failure or impaired hepatic or renal function 2
• Using higher infusion rates (5 to 15 mg/hr) for severe or postoperative hypertension 2

From the Research

Management of Hypertensive Emergency

• Hypertensive emergencies are life-threatening conditions that require immediate reduction of blood pressure with intravenous drugs, such as labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside, in an intensive care unit 3, 4, 5.
• The primary goal of intervention in a hypertensive crisis is to safely reduce blood pressure, with the appropriate therapeutic approach depending on the patient's clinical presentation 3, 4.
• Patients with hypertensive emergencies should have their blood pressure reduced by approximately 10% during the first hour and another 15% gradually over the next 2 to 3 hours to prevent cerebral hypoperfusion 4, 5.
• Oral antihypertensive therapy can usually be instituted after 6 to 12 hours of parenteral therapy, and the patient can be moved out of the intensive care unit 4, 5.

Treatment Options

• Rapid-acting intravenous antihypertensive agents, such as labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside, are available for the treatment of hypertensive emergencies 3, 4, 5.
• Newer agents, such as clevidipine, may hold considerable advantages over other available agents in the management of hypertensive crises 3, 6.
• Sodium nitroprusside is an extremely toxic drug and its use in the treatment of hypertensive emergencies should be avoided due to its potential adverse effects 3, 5.
• Other agents, such as nifedipine, nitroglycerin, and hydralazine, should not be considered first-line therapies in the management of hypertensive crises due to their significant toxicities and/or adverse effects 3, 7.

Special Considerations

• Aortic dissection requires a systolic blood pressure target of <120 mm Hg, to be achieved during the first 20 minutes using a beta-blocker and a vasodilator 4, 5.
• Pregnant women with hypertensive emergencies may be treated with magnesium and nifedipine 5, 7.
• Patients with hypertensive emergencies should be screened for secondary causes of hypertension and require long-term follow-up to ensure adequate control of hypertension and prevent further target-organ damage 5.