A Randomized Trial of Intravenous Labetalol Versus Oral Nifedipine in acute blood pressure control in hypertensive emergencies of pregnancy

OBJECTIVE: To compare safety and efficacy of intravenous labetalol with oral nifedipine to control blood pressure in hypertensive emergencies of pregnancy. DESIGN: A prospective randomized double blind comparative clinical trial SETTING: Patients admitted to Mahatma Gandhi Memorial government hospital, Tiruchirapalli. POPULATION: All pregnant women with sustained severe hypertension. METHODS: 106 consecutive patients were randomized to receive either intravenous labetalol in escalating doses of 20 mg, 40 mg, 80 mg, 80 mg, and 80 mg along with placebo tablets or nifedipine 10 mg tablet orally along with placebo saline injections every 15 minutes up to five doses. The treatment is crossed over to the other group if reduction in both systolic and diastolic blood pressure ≤ 150/100 mm Hg does not occur. PRIMARY OUTCOME: The time taken to achieve a target blood pressure of both ≤ 150 mm Hg systolic and ≤ 100 mm Hg diastolic blood pressure. RESULTS: The median time take taken to attain target blood pressure was 45 minutes and 30 minutes in labetalol and nifedipine groups, respectively (P = 0.17). Median number of doses required was three and two to achieve blood pressure control in labetalol and nifedipine groups, respectively (P = 0.23). Cross over treatment was required in 9.40% in labetalol group and 11.30% in nifedipine group (P = 0.75). Side effects profile between the two drugs were also similar (P = 0.06) CONCLUSIONS: Intravenous labetalol and oral nifedipine are equally efficacious in controlling hypertensive emergencies of pregnancy.