Hypertension in the ED

The ocular manifestations of hypertensive emergency require detailed fundoscopy, which at times can be challenging in the ED. In assessing for cardiac target organ damage, at our institution, we typically ask patients if they have experienced symptoms of dyspnea and chest pain or pressure. Generally, we also evaluate cardiac enzymes, B-type natriuretic peptide, and order ECG and chest X-ray studies when suggested by history or physical examination. Alarmingly, a study of 161 ED hypertensive (average BP of 183/109 mm Hg), asymptomatic, predominantly black patients found that 146 (90.7%) had subclinical hypertensive heart disease on point-of-care echocardiogram.⁸

Neurological/Hypertensive Encephalopathy

Hypertensive encephalopathy is a diagnosis of exclusion as alternate causes of confusion and headache, such as intracranial hemorrhage, are excluded and mental status improves with titrated BP control. Nonetheless, it is difficult to confidently state from the literature that patients who present with headache but have a normal mental status in the presence of severe hypertension are not on an early spectrum of hypertensive encephalopathy. Therefore, it is likely that the degree of symptoms should define whether target organ damage exists, though there is certainly a spectrum of hypertensive emergency—the strict definition of which is not always clear.

When a hypertensive emergency is diagnosed, management typically involves the use of antihypertensive IV medication in the intensive care unit. While such management is outside the scope of this paper, Adebayo and Rogers⁹ have published an excellent review of the care of hypertensive emergencies.

Asymptomatic Hypertension

The American College of Emergency Physicians (ACEP) has developed two clinical policies on the evaluation and management of asymptomatic hypertension in the ED. The original, published in 2006, advised that initially high BP readings of ED patients should be repeated: two separate high readings are adequate for screening, and those patients with hypertension should be referred for follow-up. Furthermore, ACEP policies note that initiating treatment in the ED is not necessary when patients are referred for follow-up. If treatment for hypertension is initiated in the ED, ACEP recommends that such management should attempt only to gradually lower BP, and not to normalize it during the initial ED visit.¹⁰

The 2013 update to ACEP’s clinical policy on managing asymptomatic hypertension expanded on the original policy. The updated policy advised against routine testing for target organ damage in patients who have asymptomatic severe hypertension. However, ACEP policy notes that evaluating serum creatinine in these patients with poor follow-up may influence patient disposition.¹¹

The 2013 policy further stated that medical intervention is not required in ED patients who have asymptomatic severe hypertension, but may be considered in patients with poor follow-up. The policies emphasize that all asymptomatic hypertensive patients should be referred for follow-up. The literature cited for the recommendation that ED patients with asymptomatic severe hypertension do not require routine investigation stems from two observational studies. These studies found that screening asymptomatic ED patients who presented with severe hypertension revealed serum creatinine abnormalities in approximately 6%, which impacted patient disposition, though it was not clear from the study results whether admission correlated to meaningful patient outcomes.^12,13

Patient Disposition

Since ACEP’s 2013 clinical policy, a study from the Cleveland Clinic has been published. This retrospective cohort study reviewed 6 years of data looking at all patients in its system with a BP of ≥180/110 mm Hg, and compared those office patients discharged to home to those referred to the ED or directly admitted to the inpatient hospital solely on the basis of severe hypertension.¹⁴ The study found that 0.5% of 387 patients referred to the ED by primary care clinics for asymptomatic severe hypertension had confirmed acute kidney injury on BMP.¹⁴ The Cleveland Clinic study also found that 2.1% of patients had evidence of target organ damage and 5.5% had any abnormal results.¹⁴ In addition, referral to the ED from the clinic for hypertension was associated with a slightly higher rate of major adverse CV events at 7 days (2 of 426 [0.5%] versus 61 of 58,109 [0.1%]; P = .02).¹⁴

The results of the Cleveland Clinic study confirm that in the absence of target organ damage, hypertension is probably best managed in the outpatient setting. The European Task Force hypertensive guidelines state “hospitalization for hypertension is regarded as inappropriate in most European countries.”¹⁵ However, from 2006 to 2012, 26% of US ED patients with primary diagnoses of hypertension were admitted to the hospital.³ In Canada’s most populous province of Ontario, from 2002 to 2011, approximately 8% of hypertensive patients were admitted.¹⁶ Part of this discrepancy may be due to the sometimes ambiguous nature of the presentation of patients with hypertension, making it unclear whether a true hypertensive emergency exists. Many patients perceive visual symptoms, headache, dizziness, and even chest pressure as the result of their elevated BP—without clear findings on fundoscopy, ECG, or cardiac marker testing. Perhaps more of these patients would be discharged if EPs felt comfortable initiating appropriate initial antihypertensive treatment.