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

June 1, 2004
Donald G. Vidt, MD
Donald G. Vidt, MD

Hypertensive crises encompass a spectrum of clinical situations thathave in common elevated blood pressure (BP) and progressive or impendingtarget organ damage. Each year more than 500,000 Americans (about1% of all persons with hypertension in the United States) have a hypertensivecrisis. In large urban areas, 25% of visits to the medical section of any givenemergency department (ED) are attributable to a hypertensive crisis.

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

A: Hypertensive crises encompass a spectrum of clinical situations thathave in common elevated blood pressure (BP) and progressive or impendingtarget organ damage. Each year more than 500,000 Americans (about1% of all persons with hypertension in the United States) have a hypertensivecrisis. In large urban areas, 25% of visits to the medical section of any givenemergency department (ED) are attributable to a hypertensive crisis.Truehypertensive emergenciesSMQ-8212-SMQthat is, severe elevations in BP (usuallyhigher than 220/140 mm Hg) that are complicated by evidence of progressivetarget organ dysfunctionSMQ-8212-SMQmake up one third of these cases. Early and appropriatetriage in the ED is critical to identify patients with this condition; they requireprompt admission to the hospital and treatment with parenteral antihypertensiveagents.

Patients with a hypertensive urgency usually have BPs above 180/110 mmHg. Despite severely elevated BP, these patients typically show no evidenceof progressive target organ dysfunctionthat would require immediate BPreduction. Patients may present withsevere headache, dyspnea, edema, orsevere anxiety; or they may beasymptomatic, with only a high BPreading.

Severe BP elevation in a patientwith diagnosed hypertension who isnoncompliant with medications or who is receiving inadequate or inappropriatetherapy represents a preventable hypertensive urgency. This underscoresthe need for aggressive long-term treatment in such patients to achieve andmaintain a goal BP.

The risks of overtreatment. Unfortunately, some patients with hypertensiveurgencies are admitted to the ICU and given parenteral therapy for rapidreduction of BP. Too many are aggressively dosed with oral agents in the EDto rapidly lower BP, a procedure that is not without risk. Oral loading doses ofantihypertensive agents can sometimes lead to cumulative effects, includinghypotension, following discharge from the ED. I believe the use of the termSMQ-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 usedagent in the ED for the initial treatment of hypertensive crisis. Administrationof 10 to 20 mg was associated with a significant reduction in BP within 15 to30 minutes. It was not until critical reviews reported an increased frequencyof acute strokes and/or myocardial infarctions, as well as some deaths, followingadministration of this agent that the FDA mandated against its use in thetreatment of hypertension. It is no longer available for that purpose in mostmajor EDs.

Appropriate care in the ED. The key caveat is that elevated BP alonerarely requires emergency therapy. Patients who have an elevated BP with noevidence of target organ damage or other impending cardiovascular event representthe majority of those who seek care in the ED. Because they are often asymptomatic, they can be observedfor a brief period in the ED. Antihypertensivetherapy can be initiated orresumed if the patient has been noncompliant;if previous treatment wasinadequate, the dosages should beincreased. These patients can be dischargedfrom the ED with elevated BP if follow-up hasbeen confirmed to ensure continued outpatient observationand adequate short-term BP control.

A relatively small group of patients who have clinicalevidence of target organ damage and/or severe headache,dyspnea, or severe anxiety in association with markedlyelevated BP may benefit from observation in the ED followingadministration of additional oral medication. In theabsence of progressive target organ dysfunction, these patientsshould not require admission.

Pharmacologic therapy. There are several oralagents that can lower BP within 1 to 3 hours (Table).They may also be useful as add-on agents. When clinicallystable, patients may safely be sent home after their oralmedication regimen has been adjusted and arrangementshave been made for follow-up within 24 to 72 hours in theoutpatient setting.

To discharge a patient from the ED without a confirmedfollow-up appointment represents a missed opportunityto achieve optimal BP control, as well as to identifypossible causes of hypertension. Historically, physicianshave placed a strong emphasis on acute lowering of BP tonear normal levels, but patients are frequently lost to outpatientfollow-up. They subsequently have a very high rateof repeated ED visits, often with additional hypertensivecomplications.

It is time to drop the term SMQ-8220-SMQhypertensive urgencySMQ-8221-SMQ infavor of a less ominous descriptive phrase, such asSMQ-8220-SMQuncontrolled BP.SMQ-8221-SMQ There is little justification for admittingpatients with uncontrolled BP to a hospital for furtherevaluation and management when this condition can beefficiently and cost-effectively managed in the outpatientsetting.