What are the treatment differences between hypertensive urgency and hypertensive emergency?

From the Guidelines

The key difference in treatment between hypertensive urgency and hypertensive emergency lies in the timing, setting, and approach to blood pressure reduction, with hypertensive urgency managed in an outpatient setting and hypertensive emergency requiring immediate hospitalization and intravenous medications. Hypertensive urgency, where blood pressure is severely elevated without evidence of acute end-organ damage, can typically be managed in an outpatient setting with oral medications aiming for gradual blood pressure reduction over 24-48 hours. Commonly used medications include labetalol (100-300mg orally every 6-8 hours), amlodipine (5-10mg daily), or captopril (25mg orally) 1. In contrast, hypertensive emergency involves severely elevated blood pressure with evidence of acute end-organ damage and requires immediate hospitalization, preferably in an intensive care unit, with intravenous medications to lower blood pressure by 20-25% within the first hour, then to 160/100 mmHg over the next 2-6 hours. First-line IV medications include labetalol (20-80mg bolus every 10 minutes or 0.5-2mg/min infusion), nicardipine (5-15mg/hr infusion), or clevidipine (1-2mg/hr initially, titrated up) 1.

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

• 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 1.
• Continuous infusion of short-acting titratable antihypertensive agents is often preferable to prevent further target organ damage 1.
• The therapeutic goal is to minimize target organ damage safely by rapid recognition of the problem and early initiation of appropriate antihypertensive treatment 1.
• Compelling conditions requiring rapid lowering of SBP, usually to <140 mm Hg, in the first hour of treatment include aortic dissection, severe preeclampsia or eclampsia, and pheochromocytoma with hypertensive crisis 1.

It's also important to note that there is no RCT evidence comparing different strategies to reduce BP, except in patients with ICH, and no high-quality RCT evidence to inform clinicians as to which first-line antihypertensive drug class provides more benefit than harm in hypertensive emergencies 1. However, clinical experience indicates that antihypertensive therapy is an overall benefit in a hypertensive emergency 1.

From the Research

Treatment Differences

The treatment of hypertensive urgency and hypertensive emergency differs significantly.

• In hypertensive urgency, there is no end-organ injury, and the goal is to lower blood pressure gradually over 24 to 48 hours using oral antihypertensives 2.
• In hypertensive emergency, there is an immediate threat to the integrity of the cardiovascular system, and blood pressure should be immediately reduced to avoid further end-organ damage 2, 3, 4.

Oral Antihypertensives for Hypertensive Urgencies

Oral antihypertensives such as nifedipine, captopril, clonidine, labetalol, and prazosin are effective in managing hypertensive urgencies 2, 4, 5, 6.

• These agents can lower blood pressure rapidly and predictably, but their use is also associated with adverse effects 6.
• The choice of agent should be based on the perceived need for urgent blood pressure control, the cause of the hypertensive urgency, and concomitant conditions 6.

Parenteral Antihypertensives for Hypertensive Emergencies

Parenteral antihypertensives such as sodium nitroprusside, nitroglycerin, and hydralazine are commonly used to treat hypertensive emergencies 2, 3, 4.

• Sodium nitroprusside is the most popular agent, but it should be used with caution in patients with impaired cerebral flow 2, 4.
• Nitroglycerin is preferred when there is acute coronary insufficiency, and a beta-blocker may be added in some patients 2.
• Newer agents such as nicardipine, fenoldopam, labetalol, and esmolol are also effective and may have a better safety profile than traditional agents 3, 4.

Special Considerations

Certain conditions require special consideration when treating hypertensive emergencies or urgencies.

• In patients with eclampsia, hydralazine is the drug of choice, while labetalol, urapidil, or calcium antagonists are possible alternatives 2.
• In patients with catecholamine-induced crises, an alpha-blocker such as phentolamine should be given, while labetalol or sodium nitroprusside with beta-blockers are alternatives 2.
• In patients with aortic dissection, rapid controlled titration of arterial pressure to normal levels using intravenous sodium nitroprusside and a beta-blocker is recommended 2.