Hypertension Q&A: When Is an urgency not an emergency

By DONALD G. VIDT, MDSMQ-8212-SMQ-Series Editor

Q:How urgent is a SMQ-8220-SMQhypertensive urgencySMQ-8221-SMQ?

A: Hypertensive crises encompass a spectrum of clinical situations that have in common elevated blood pressure (BP) and progressive or impending target organ damage. Each year more than 500,000 Americans (about 1% of all persons with hypertension in the United States) have a hypertensive crisis. In large urban areas, 25% of visits to the medical section of any given emergency department (ED) are attributable to a hypertensive crisis. Truehypertensive emergenciesSMQ-8212-SMQthat is, severe elevations in BP (usually higher than 220/140 mm Hg) that are complicated by evidence of progressive target organ dysfunctionSMQ-8212-SMQmake up one third of these cases. Early and appropriate triage in the ED is critical to identify patients with this condition; they require prompt admission to the hospital and treatment with parenteral antihypertensive agents.

Patients with a hypertensive urgency usually have BPs above 180/110 mm Hg. Despite severely elevated BP, these patients typically show no evidence of progressive target organ dysfunction that would require immediate BP reduction. Patients may present with severe headache, dyspnea, edema, or severe anxiety; or they may be asymptomatic, with only a high BP reading.

Severe BP elevation in a patient with diagnosed hypertension who is noncompliant with medications or who is receiving inadequate or inappropriate therapy represents a preventable hypertensive urgency. This underscores the need for aggressive long-term treatment in such patients to achieve and maintain a goal BP.

The risks of overtreatment. Unfortunately, some patients with hypertensive urgencies are admitted to the ICU and given parenteral therapy for rapid reduction of BP. Too many are aggressively dosed with oral agents in the ED to rapidly lower BP, a procedure that is not without risk. Oral loading doses of antihypertensive agents can sometimes lead to cumulative effects, including hypotension, following discharge from the ED. I believe the use of the term SMQ-8220-SMQhypertensive urgencySMQ-8221-SMQ has contributed to the tendency to overtreat patients, with no evidence of short-term benefit.

A few years ago, short-acting nifedipine( was the most commonly used agent in the ED for the initial treatment of hypertensive crisis. Administration of 10 to 20 mg was associated with a significant reduction in BP within 15 to 30 minutes. It was not until critical reviews reported an increased frequency of acute strokes and/or myocardial infarctions, as well as some deaths, following administration of this agent that the FDA mandated against its use in the treatment of hypertension. It is no longer available for that purpose in most major EDs.

Appropriate care in the ED. The key caveat is that elevated BP alone rarely requires emergency therapy. Patients who have an elevated BP with no evidence of target organ damage or other impending cardiovascular event represent the majority of those who seek care in the ED. Because they are often asymptomatic, they can be observed for a brief period in the ED. Antihypertensive therapy can be initiated or resumed if the patient has been noncompliant; if previous treatment was inadequate, the dosages should be increased. These patients can be discharged from the ED with elevated BP if follow-up has been confirmed to ensure continued outpatient observation and adequate short-term BP control.

A relatively small group of patients who have clinical evidence of target organ damage and/or severe headache, dyspnea, or severe anxiety in association with markedly elevated BP may benefit from observation in the ED following administration of additional oral medication. In the absence of progressive target organ dysfunction, these patients should not require admission.

Pharmacologic therapy. There are several oral agents that can lower BP within 1 to 3 hours (Table). They may also be useful as add-on agents. When clinically stable, patients may safely be sent home after their oral medication regimen has been adjusted and arrangements have been made for follow-up within 24 to 72 hours in the outpatient setting.

To discharge a patient from the ED without a confirmed follow-up appointment represents a missed opportunity to achieve optimal BP control, as well as to identify possible causes of hypertension. Historically, physicians have placed a strong emphasis on acute lowering of BP to near normal levels, but patients are frequently lost to outpatient follow-up. They subsequently have a very high rate of repeated ED visits, often with additional hypertensive complications.

It is time to drop the term SMQ-8220-SMQhypertensive urgencySMQ-8221-SMQ in favor of a less ominous descriptive phrase, such as SMQ-8220-SMQuncontrolled BP.SMQ-8221-SMQ There is little justification for admitting patients with uncontrolled BP to a hospital for further evaluation and management when this condition can be efficiently and cost-effectively managed in the outpatient setting.