What is the management of hypertensive emergency?

From the Guidelines

Hypertensive emergency management requires immediate intervention to prevent end-organ damage, with the goal of reducing blood pressure by no more than 25% within the first hour, then 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 hypertensive thrombotic microangiopathy 1.
• First-line medications include labetalol, nicardipine, or clevidipine, with dosages and administration rates as follows:
  • Labetalol: 10-20 mg IV bolus, followed by 20-80 mg every 10 minutes or infusion at 0.5-2 mg/min
  • Nicardipine: 5 mg/hr IV, titrated by 2.5 mg/hr every 5-15 minutes, maximum 15 mg/hr
  • Clevidipine: 1-2 mg/hr IV, doubled every 90 seconds until near target, maximum 32 mg/hr
• For patients with acute pulmonary edema or heart failure, nitroglycerin (5-100 mcg/min IV) is recommended, while for aortic dissection, combining beta-blockers (esmolol 250-500 mcg/kg/min IV) with vasodilators to achieve systolic BP below 120 mmHg is advised.

Special Considerations

• Avoid rapid BP reduction in acute stroke unless BP exceeds 220/120 mmHg, as recommended by the European Heart Journal 1.
• Concurrent management should include establishing IV access, continuous cardiac monitoring, frequent vital sign checks, neurological assessments, and treating the underlying cause.
• Rapid BP reduction is necessary because sustained severe hypertension can cause progressive damage to the brain, heart, kidneys, and other vital organs through endothelial injury, fibrinoid necrosis of small vessels, and tissue ischemia.

Clinical Presentations

• Malignant hypertension: Severe BP elevation (commonly >200/120 mm Hg) associated with advanced bilateral retinopathy (hemorrhages, cotton wool spots, papilledema) 1.
• Hypertensive encephalopathy: Severe BP elevation associated with lethargy, seizures, cortical blindness and coma in the absence of other explanations 1.
• Hypertensive thrombotic microangiopathy: Severe BP elevation associated with hemolysis and thrombocytopenia in the absence of other causes and improvement with BP-lowering therapy 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 mean time to therapeutic response for severe hypertension, defined as diastolic blood pressure less than or equal to 95 mmHg or greater or equal to 25 mmHg decrease and systolic blood pressure less than or equal to 160 mmHg, was 77 ± 5 minutes. The average maintenance dose was 8. 0 mg/hr.

Hypertensive Emergency Management:

• Nicardipine (IV): Initiate therapy at 5 mg/hr and titrate every 15 minutes by 2.5 mg/hr up to a maximum of 15 mg/hr for gradual reduction, or every 5 minutes for more rapid reduction.
• Labetalol (IV): Initial dose of 0.25 mg/kg, followed by additional doses of 0.5 mg/kg at 15-minute intervals, up to a total cumulative dose of 1.75 mg/kg, or an initial dose of 20 mg followed by 40 or 80 mg at 10-minute intervals.
• The choice of medication and dosage regimen should be individualized based on the patient's condition and response to treatment 2, 2, 3.
• Key Considerations:
  • Monitor blood pressure and heart rate closely during treatment.
  • Adjust the infusion rate as needed to maintain desired response.
  • Be aware of potential side effects, such as hypotension, tachycardia, and postural hypotension.

From the Research

Hypertensive Emergency Management

• Hypertensive emergencies require immediate reduction in blood pressure with titratable, short-acting, intravenous antihypertensive agents, as they involve acute end-organ damage 4.
• 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 4, 5.
• Patients with hypertensive emergencies are best treated in an intensive care unit with titratable, intravenous, hypotensive agents, such as labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside 4, 6.

Treatment Options

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

Management Approach

• The management of hypertensive emergencies and urgencies differs in both the rapidity of blood pressure correction and the medications used, with hypertensive emergencies requiring immediate treatment with intravenous antihypertensive medications 8.
• Hypertensive urgencies may be treated with oral antihypertensive agents to reduce the blood pressure to baseline or normal over a period of 24-48 hours 8.
• Appropriate identification, evaluation, and treatment of hypertensive crises are of great importance in the emergency department to prevent progression of organ damage and death 8.