A prospective randomized trial of magnesium sulfate in severe preeclampsia: Use of diuresis as a clinical parameter to determine the duration of postpartum therapy

Objective: The purpose of this study was to assess the use of the onset of diuresis in the determination of the duration of postpartum magnesium sulfate therapy among patients with severe preeclampsia. Study design: A prospective randomized trial of postpartum therapy with magnesium sulfate was conducted. The control group received 24 hours of therapy, and the study group received therapy until the onset of diuresis (urine output >100 mL/hr for 2 consecutive hours). The Student t test, χ² test, and Fisher's exact test were used for analysis of data; a probability value of <.05 was considered statistically significant. Results: There were 50 patients in the control group and 48 patients in the study group. There was no difference in maternal demographic data, severe disease criteria, blood pressure, 24-hour postpartum urine output, or need for antihypertensive therapy. The study group had a significantly shorter duration of therapy, and no patient had eclampsia or required the re-initiation of therapy. Conclusion: The use of the onset of diuresis in the postpartum period as the determinant clinical parameter for the discontinuation of magnesium sulfate in patients with severe preeclampsia was associated with no untoward outcomes or need for the re-initiation of treatment.