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

Abstract

Background Intravenous hydralazine is approved for the treatment of hypertensive emergency and widely used for hypertension associated with toxemia of pregnancy. As we had observed increased off-label use of this agent in area hospitals, we studied its use in a University teaching hospital. Methods Patients were identified prospectively between April and October 2010 from all hospitalized patients who had an order for intravenous hydralazine entered into the computerized physician order entry system. Clinician prescribers were unaware that this study was being conducted. Demographic and clinical information, including pre-treatment blood pressure (BP), change in BP and heart rate (HR) within 2 hours post-administration of hydralazine, concurrent and follow-up antihypertensive medications, and adverse events were obtained. Results There were 94 patients (mean age, 69 ± 18 years, 48% women, 89% with chronic hypertension) who received 201 intravenous hydralazine doses (mean dose of 11.4 ± 4.3 mg). Only 4 (2%) of patients had evidence of an urgent hypertensive condition (e.g., symptoms, target organ injury). Baseline BP was 175/82 ± 25/16 mmHg and following hydralazine was reduced by 24/9 ± 29/15 mmHg while HR increased by 4 ± 13 beats/min. Changes from baseline in BP were related to baseline BP: change in BP in the lower baseline range was −3 ± 20 mmHg while change observed in those with the highest range of baseline blood pressure was −35 ± 25 mmHg. Seventeen patients experienced an adverse event, the most common being hypotension (n=11). Conclusions Intravenous hydralazine is commonly prescribed for non-urgent cases of hypertension in the hospitalized patient. Changes in systolic BP, while related to baseline BP values, are nevertheless, highly variable. There is risk of hypotension associated with its use. There is evidence that this agent is not useful for many patients with hypertension in the hospital setting and may cause harm if used inappropriately.

As‐needed intravenous antihypertensive therapy and blood pressure control

“…In addition to there being no proven clinical benefit in this setting, the use of unnecessary IV antihypertensives is associated with unnecessary risks and excess cost. Another report of IV hydralazine in asymptomatic patients found that 17 of 94 patients experienced an adverse effect after administration . Not only is the drug acquisition cost for IV antihypertensives greater than their oral counterparts, often by a factor of 10 to 100, the intravenous route requires additional care to monitor their effects, adding to the human resource expense.…”

“…Another report of IV hydralazine in asymptomatic patients found that 17 of 94 patients experienced an adverse effect after administration. 18 Not only is the drug acquisition cost for IV antihypertensives greater than their oral counterparts, often by a factor of 10 to 100, the intravenous route requires additional care to monitor their effects, adding to the human resource expense. Finally, the onset of action of intravenous agents is generally more rapid, which increases the risk of inducing hypotension and therefore targetorgan ischemia.…”

An Update on Inpatient Hypertension Management

“…In a retrospective cohort study, only 2.9 % of hospitalized patients treated with IV hydralazine or labetalol for HTN had evidence of diseases caused by hypertensive damage [21]. Similarly, a separate study also looking at the use of IV hydralazine showed only 2 % of treated patients showed signs of hypertensive emergency, and 8 % of patients experienced adverse events [62]. Intravenous hydralazine seems to be a drug of choice in many of these patients, perhaps because of ease of access on most non-ICU medical wards [63].…”

Improving the use of intravenous antihypertensive medications in the hospital setting: a quality improvement initiative for patient safety

“…There is increasing concern about the use of IVAH as well as the increased use of these agents in treating asymptomatic hypertension without any established guidelines about when and when not to use them 8 9. Clinical evidence thus far recommends conservative management of asymptomatic hypertension in the hospital setting with observation, oral antihypertensive medication and outpatient follow-up with a primary care provider 10…”