What is the treatment for hypertensive emergency?

From the Guidelines

Hypertensive emergency treatment requires immediate intervention with intravenous antihypertensive medications to lower blood pressure in a controlled manner, with the goal of reducing mean arterial pressure by no more than 25% within the first hour, then to 160/100-110 mmHg within the next 2-6 hours, and normalize over 24-48 hours, 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, 2, 3, 4, 5, 6.

The selection of an antihypertensive agent should be based on the drug’s pharmacology, pathophysiological factors underlying the patient’s hypertension, degree of progression of target organ damage, the desirable rate of BP decline, and the presence of comorbidities. First-line medications include:

• Nicardipine (initial dose 5 mg/hr IV, titrate by 2.5 mg/hr every 5-15 minutes, maximum 15 mg/hr)
• Labetalol (20-80 mg IV bolus every 10 minutes or 0.5-2 mg/min infusion)
• Clevidipine (1-2 mg/hr IV, double rate every 90 seconds until near goal, maximum 32 mg/hr)

Sodium nitroprusside (0.3-10 mcg/kg/min) is effective but requires arterial line monitoring and can cause cyanide toxicity with prolonged use. Patients require ICU admission with continuous cardiac monitoring, frequent vital signs, neurological checks, and assessment of end-organ damage through laboratory tests (BUN, creatinine, electrolytes, cardiac enzymes) and imaging as indicated. The underlying cause of hypertension must be identified and treated. Oral antihypertensives should be initiated or adjusted once the patient is stable to ensure long-term blood pressure control and prevent recurrence.

Some key points to consider in the management of hypertensive emergencies include:

• The importance of rapid recognition and early initiation of appropriate antihypertensive treatment to minimize target organ damage
• The need for continuous infusion of short-acting titratable antihypertensive agents to prevent further target organ damage
• The potential for certain comorbidities, such as acute aortic dissection or severe preeclampsia, to require more rapid lowering of blood pressure
• The importance of monitoring for potential adverse effects, such as cyanide toxicity with sodium nitroprusside, and adjusting treatment accordingly.

Overall, the management of hypertensive emergencies requires a careful and individualized approach, taking into account the patient's specific clinical presentation, comorbidities, and response to treatment.

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 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. In a clinical pharmacologic study in severe hypertensives, an initial 0. 25 mg/kg injection of labetalol HCl, administered to patients in the supine position, decreased blood pressure by an average of 11/7 mmHg. Additional injections of 0.5 mg/kg at 15-minute intervals up to a total cumulative dose of 1.75 mg/kg of labetalol HCl caused further dose-related decreases in blood pressure.

Hypertensive Emergency Treatment

• Nicardipine (IV): Initiate therapy at a rate of 5 mg/hr and 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 7.
• Labetalol (IV): An initial dose of 0.25 mg/kg can be administered, followed by additional doses of 0.5 mg/kg at 15-minute intervals up to a total cumulative dose of 1.75 mg/kg 8.

From the Research

Hypertensive Emergency Treatment

• Hypertensive emergencies require immediate reduction in blood pressure with a titratable, short-acting, intravenous antihypertensive agent, as they involve acute end-organ damage 9, 10, 11.
• 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 9, 10.
• Patients with hypertensive emergencies are best treated in an intensive care unit with titratable, intravenous, hypotensive agents, such as labetalol, esmolol, fenoldopam, nicardipine, and clevidipine 9, 12, 13.
• Sodium nitroprusside, nifedipine, nitroglycerin, and hydralazine are not recommended as first-line therapies due to their toxicities and adverse effects 9, 12.

Treatment Options

• Rapid-acting intravenous antihypertensive agents, including labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside, are available for treating hypertensive emergencies 9.
• Newer agents, such as clevidipine and fenoldopam, may offer advantages over other available agents in managing hypertensive crises 9, 12, 13.
• Clevidipine, a third-generation dihydropyridine calcium-channel blocker, has unique pharmacodynamic and pharmacokinetic properties and has been shown to reduce mortality compared to nitroprusside 12, 13.

Management Approach

• Hypertensive emergencies must be treated immediately with intravenous antihypertensive medications, whereas hypertensive urgencies may be treated with oral antihypertensive agents to reduce blood pressure to baseline or normal over 24-48 hours 10.
• Appropriate identification, evaluation, and treatment of hypertensive crises are crucial in the emergency department to prevent progression of organ damage and death 10.