Utility of Routine Testing for Patients With Asymptomatic Severe Blood Pressure Elevation in the Emergency Department

Abstract

Recommendations for the treatment of emergency department (ED) patients with asymptomatic severely elevated blood pressure advise assessment for occult, acute hypertensive target-organ damage. This study determines the prevalence of unanticipated, clinically meaningful test abnormalities in ED patients with asymptomatic severely elevated blood pressure. This was a prospective observational study at 3 urban academic EDs. Consecutive patients with systolic blood pressure greater than or equal to 180 mm Hg or diastolic blood pressure greater than or equal to 110 mm Hg on 2 measurements were enrolled if they denied symptoms of hypertensive emergency. A basic metabolic panel, urinalysis, ECG, CBC count, and chest radiograph were obtained. Treating physicians were interviewed about the indication for each test and whether an abnormal result was anticipated according to clinical findings. When test results were available, physicians were asked whether abnormal findings were clinically meaningful, defined as leading to unanticipated hospitalization, medication modification, or further immediate evaluation. The primary outcome was the prevalence of unanticipated clinically meaningful test abnormalities. One hundred nine patients with asymptomatic severely elevated blood pressure were enrolled. Unanticipated abnormal test results were noted in 57 (52%) patients. Clinically meaningful unanticipated test abnormalities were found in 7 (6%) patients: basic metabolic panel in 2 (2%), CBC count in 3 (3%), urinalysis in 3 (4%), ECG in 2 (2%), and chest radiograph in 1 (1%). Five patients (5%) had abnormalities assessed as possible manifestations of acute hypertensive target-organ injury; none had abnormalities clearly related to severely elevated blood pressure. Screening tests of urban ED patients with asymptomatic severely elevated blood pressure infrequently detect unanticipated hypertension-related abnormalities that alter ED management.