Randomized, Controlled Trial of Hydralazine Versos Nifedipine in Preeclamptic Women with Acute Hypertension

Abstract

We studied 37 nulliparous women with late-onset gestational hypertension and significant proteinuria, with a diastolic blood pressure of 110 mmHg or higher. They were randomly assigned to receive intravenous hydralazine (5 ou 10 mg) plus an oral placebo; or oral nifedipine (10 or 20 mg) plus an intravenous placebo, with the goal of maintaining diastolic blood pressure at or below 100 mmHg. All drugs were administered in a double-blind fashion. Hydralazine decreased mean arterial pressure from 136± mmHg to 106±7 mmHg, while nifedipine decreased it from 135±8 mmHg to 109±10 mmHg. The incidence of adverse maternal and fetal effects were similar in the two treatment groups. This randomized trial contained a limited number of subjects and, therefore, did not have the statistical power to detect small differences between hydralazine and nifedipine. However, we have demonstrated that a trial of drug therapies for acute hypertension in pregnancy can be successfully blinded, and this approach would be valuable in a larger study comparing the treatment regimens addressed here.