Acute Management of Severe Asymptomatic Hypertension

TREATMENT

Knowing who to treat and when is a vast area of debate among emergency and primary care providers. Patients with hypertension who have established risk factors are known to have worse outcomes than those who may be otherwise healthy. Some clinicians believe that patients presenting with hypertensive urgency should be discharged home without screening and/or treatment. However, because uncontrolled severe hypertension can lead to acute complications (eg, MI, cerebrovascular accident), in practice, many providers are unwilling to send the patient home without workup.¹² The patient’s condition must be viewed in the context of the entire disease spectrum, including risk factors.

The Figure offers a disposition pathway of recommendations based on risk stratification as well as screening tools for some of the less common causes of hypertensive urgency. Regardless of the results of screening tests or the decision to treat, affected patients require close primary care follow-up. Many of these patients may need further testing and careful management of their BP medication regimen.

How to treat

For patients with severe asymptomatic hypertension, if the history, physical, and screening tests do not show evidence of end-organ damage, BP can be controlled within 24 to 48 hours.^5,10,11,21 In adults with hypertensive urgency, the most reasonable goal is to reduce the BP to ≤ 160/100 mm Hg^5-7; however, the mean arterial pressure should not be lowered by more than 25% within the first two to three hours.¹³

Patients at high risk for imminent neurovascular, cardiovascular, renovascular, or pulmonary events should have their BP lowered over a period of hours, not minutes. In fact, there is evidence that rapid lowering of BP in asymptomatic patients may cause adverse outcomes.⁶ For example, in patients with acute ischemic stroke, increases in cerebral perfusion pressure promote an increase in vascular resistance—but decreasing the cerebral perfusion pressure abruptly will thereby decrease the cerebral blood flow, potentially causing cerebral ischemia or a worsening of the stroke.^9,14

Treatment options

A broad spectrum of therapeutic options has proven helpful in lowering BP over a short period of time, including oral captopril, clonidine, hydralazine, labetalol, and hydrochlorothiazide (see Table 3).^7,9,12,15 Nifedipine is contraindicated because of the abrupt and often unpredictable reduction in BP and associated myocardial ischemia, especially in patients with MI or left ventricular hypertrophy.^14,22,23 In cases of hypertensive urgency secondary to cocaine abuse, benzodiazepines would be the drug of choice and ß-blockers should be avoided due to the risk for coronary vasoconstriction.⁷

For patients with previously treated hypertension, the following options are reasonable: Increase the dose of the current antihypertensive medication; add another agent; reinstitute prior antihypertensive medications in nonadherent patients; or add a diuretic.

In patients with previously untreated hypertension, no clear evidence supports using one particular agent over another. However, initial treatment options that are generally considered safe include an ACE inhibitor, an angiotensin receptor blocker, a calcium channel blocker, or a thiazide diuretic.¹⁵ A few examples of medications within these categories include lisinopril (10 mg PO qd), losartan (50 mg PO qd), amlodipine (2.5 mg PO qd), or hydrochlorothiazide (25 mg PO qd).

Close follow-up is essential when an antihypertensive medication is started or reinstituted. Encourage the patient to reestablish care with their primary care provider (if you do not fill that role). You may need to refer the patient to a new provider or, in some cases, have the patient return to the ED for a repeat BP check.

CONCLUSION

The challenges of managing patients with hypertensive urgency are complicated by low follow-up rates with primary physicians, difficulty in obtaining referrals and follow-up for the patient, and hesitancy of providers to start patients on new BP medications. This article clarifies a well-defined algorithm for how to screen and risk-stratify patients who present to the ED or primary care office with hypertensive urgency.