Comparison of intravenous labetalol and hydralazine for severe hypertension in pregnancy in Northeastern Nigeria: A randomized controlled trial

Abstract

Objectives: The objectives were to compare the efficacy and safety of intravenous hydralazine and labetalol for acutely lowering severe hypertension in pregnancy.

Study design: This was a superiority parallel double-blinded randomized controlled trial conducted from October 2018 to June 2019 in two hospitals in Gombe, Nigeria. Pregnant women with a live singleton fetus at gestational age of at least 28 weeks with severe hypertension were randomized (60 per group) to receive incremental doses of either intravenous labetalol (20 mg; 40 mg; 80 mg; 80 mg; and 80 mg) or 10 mg of intravenous hydralazine - up to a maximum of 5 doses - until the target blood pressure was achieved or the study was terminated.

Main outcome measures: The main outcome measures were the mean reduction in mean arterial blood pressure and occurrence of persistent hypertension. Other endpoints were maternal side-effects, perinatal death, Apgar score at birth and SCBU admission.

Results: One hundred and thirteen patients' data were analyzed (fifty-six [56] in the hydralazine group and fifty-seven [57] in the labetalol group). There were no significant differences in the fall of the mean arterial blood pressure (labetalol; 24.19 mmHg/hydralazine; 27.68 mmHg) (p = 0.192), maternal side effects, perinatal deaths, Apgar scores and SCBU admission between the two groups. Hydralazine, however, produced a more marked reduction in diastolic blood pressure than labetalol (p = 0.012).

Conclusion: Both labetalol and hydralazine are effective for acute blood pressure control in pregnancy with a similar safety profile. This study was self-funded and registered in the Pan African Clinical Trials Registry (www.pactr.orgPACTR202010738538062).

Keywords: Hydralazine; Labetalol; Nigeria; Pregnancy; Severe hypertension.