What is the management of a hypertensive emergency?

From the Guidelines

Hypertensive emergency management requires immediate intervention to prevent end-organ damage, 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 to normal over the following 24-48 hours, as recommended by the 2020 international society of hypertension global hypertension practice guidelines 1.

Key Considerations

• Begin with rapid but controlled blood pressure reduction using intravenous medications, such as labetalol, nicardipine, or clevidipine, as these are first-line agents for hypertensive emergencies 1.
• Specific conditions require tailored approaches:
  • Aortic dissection: target SBP <120 mmHg using beta-blockers (esmolol, metoprolol) plus vasodilators 1.
  • Ischemic stroke: only treat if BP >220/120 mmHg 1.
  • Intracerebral hemorrhage: maintain SBP <160 mmHg 1.
  • Preeclampsia: use labetalol, nicardipine, or hydralazine while administering magnesium sulfate to prevent seizures 1.

Monitoring and Transition

• Continuous cardiac and blood pressure monitoring is essential during treatment 1.
• Once stabilized, transition to oral antihypertensives and investigate underlying causes such as medication non-adherence, secondary hypertension, or substance use that may have precipitated the crisis 1.

Evidence-Based Recommendations

The 2020 international society of hypertension global hypertension practice guidelines 1 provide the most recent and highest quality evidence for the management of hypertensive emergencies, and should be followed to ensure optimal patient outcomes.

From the FDA Drug Label

Nicardipine hydrochloride injection is administered by slow continuous infusion at a concentration of 0. 1 mg/mL. 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.

Management of Hypertension Emergency with Nicardipine:

• Initiate therapy at 5 mg/hr and titrate as needed to achieve desired blood pressure reduction.
• Increase infusion rate by 2.5 mg/hr every 15 minutes, up to a maximum of 15 mg/hr.
• For more rapid blood pressure reduction, titrate every 5 minutes. 2

Following discontinuation of intravenous treatment with labetalol HCl, the blood pressure rose gradually and progressively, approaching pretreatment baseline values within an average of 16 to 18 hours in the majority of patients Labetalol HCl administered as a continuous intravenous infusion, with a mean dose of 136 mg (27 to 300 mg) over a period of 2 to 3 hours (mean of 2 hours and 39 minutes) lowered the blood pressure by an average of 60/35 mmHg

Management of Hypertension Emergency with Labetalol:

• Initial dose: 0.25 mg/kg or 20 mg
• Additional doses: 0.5 mg/kg or 40-80 mg at 10-15 minute intervals
• Continuous infusion: mean dose of 136 mg over 2-3 hours 3

From the Research

Definition and Classification of Hypertensive Crises

• Hypertensive crises can be classified into two categories: hypertensive emergencies and hypertensive urgencies, depending on the presence or absence of acute end-organ damage 4, 5, 6.
• Hypertensive emergencies are characterized by elevated blood pressure with acute end-organ damage, requiring immediate treatment with intravenous antihypertensive agents 4, 5, 6.
• Hypertensive urgencies, on the other hand, are characterized by elevated blood pressure without acute end-organ damage, and can be treated with oral antihypertensive agents 4, 5, 6.

Treatment of Hypertensive Emergencies

• The primary goal of treatment in hypertensive emergencies is to safely reduce blood pressure and prevent further end-organ damage 4, 5, 6.
• Intravenous antihypertensive agents, such as labetalol, esmolol, fenoldopam, nicardipine, and sodium nitroprusside, are commonly used to treat hypertensive emergencies 4, 5, 7.
• However, sodium nitroprusside is considered an extremely toxic drug and its use should be avoided whenever possible 4.
• Newer agents, such as clevidipine and fenoldopam, may offer advantages over traditional agents in the management of hypertensive crises 4, 5.

Comparison of Intravenous Antihypertensive Agents

• A systematic review comparing nicardipine and labetalol for the management of hypertensive crises found comparable efficacy and safety between the two agents, although nicardipine may provide more predictable and consistent blood pressure control 7.
• Other studies have also compared the efficacy and safety of different intravenous antihypertensive agents, including esmolol, fenoldopam, and sodium nitroprusside 5, 7.

Practical Approach to Management

• A recent review proposed a novel symptoms- and evidence-based algorithm for the assessment and treatment of hypertensive emergencies, emphasizing the importance of quick identification of acute organ damage and immediate treatment in a proper setting 8.
• The algorithm, known as the BARKH-based algorithm, aims to streamline the management of hypertensive emergencies and improve patient outcomes 8.