Intravenous hydralazine for blood pressure management in the hospitalized patient: its use is often unjustified

Abstract

Due to observations of increased off-label use of intravenous hydralazine in area hospitals, we studied its use in a university teaching hospital. Patients were prospectively identified between April and October 2010 with a pharmacy order for intravenous hydralazine. Demographic and clinical information, including pretreatment blood pressure (BP), change in BP and heart rate within 2 hours after administration of hydralazine, and adverse events were obtained. Ninety-four patients (mean age, 69 ± 18 years, 48% women, 89% with known hypertension) received 201 intravenous hydralazine doses (mean dose of 11.4 ± 4.3 mg). Only 4 (2%) patients had evidence of an urgent hypertensive condition. Following hydralazine, BP was reduced by 24/9 ± 29/15 mmHg and heart rate increased by 4 ± 13 beats per minute. Changes from baseline in BP were related to baseline BP. Seventeen patients experienced an adverse event, the most common being hypotension (n = 11). Intravenous hydralazine is commonly prescribed for non-urgent cases of hypertension in the hospitalized patient. While changes in systolic BP are related to baseline BP values, they are highly variable, and associated with hypotension. Thus, this agent may not be useful for treating hypertension in many hospitalized patients and may cause harm if used inappropriately.