Nitroglycerin versus labetalol to control the blood pressure in acute severe pre-eclampsia

Abstract

Background: Acute severe pre-eclampsia (PE) requires urgent antihypertensive therapy to reduce the incidence of adverse outcome. There is currently very limited evidence for the role of nitric oxide donors as antihypertensive therapy for acute severe PE. The aim of this study was to evaluate the efficiency and tolerability of nitroglycerin compared to labetalol in terms of acute control of blood pressure in severe PE. Patients and methods: Two hundred patients with severe PE were admitted prepartum to the ICU to stabilize blood pressure. They were randomly assigned to one of two groups; Group N received nitroglycerin intravenous infusion (1 mg/ml) and Group L received labetalol intravenous infusion (10 mg/ml). The starting infusion rate was 5 ml/hr and was titrated to stabilize systolic blood pressure at 130–140 mmHg and diastolic blood pressure at 80–90 mmHg (study end point). Results: Reduction of blood pressure at 90 minutes to the desired end point was achieved in 96% and 87% of the patients by nitroglycerin and labetalol infusion respectively. Nitroglycerin showed significantly faster control and lower incidence of persistent hypertension. The number of attacks of hypotension was comparable between both the groups. Headache, flushes, and tachycardia were significantly higher in N group compared to the L group, while bradycardia was significantly lower in the N group compared to the L group. Fetal side effects were comparable between the two groups. Conclusion: Nitroglycerin can be considered an important alternative to labetalol for controlling the blood pressure in acute severe PE.