Nitroglycerin Versus Labetalol in Acute Severe Pre-eclampsia

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 (100 in each group): Group N received nitroglycerine intravenous infusion in a concentration of 1 mg/ml, thus 1µg/Kg/min equals to 4.8 ml/hr for an 80 Kg patient. Group L received labetalol intravenous infusion in a concentration of 10 mg/ ml, thus 50 mg/ml equals to 5 ml/hr. The starting infusion rate of the antihypertensive medication was 5 ml/hr. The infusion rate was titrated to stabilize systolic blood pressure (SBP) at 130-140 mmHg and diastolic blood pressure (DBP) at 80-90 mmHg (study end point) by adjusting the infusion rate as required either by maintaining the same infusion rate or by changing its infusion rate by 1 ml/hr up or down according to the clinical condition every 10 minutes. On any abrupt reduction in blood pressure below 120 mmHg for SBP or 80 mmHg for DBP, the infusion was immediately discontinued, and a bolus of 150 ml lactate ringer was given.