Using blood pressure and urine output as a guide for the duration of magnesium sulphate therapy as a prophylaxis against seizures among patients with severe preeclampsia

ABSTRACT

To assess whether we can use blood pressure and urine output to adjust the duration at postpartum magnesium sulphate as a prophylaxis against seizures in patients with severe preeclampsia. This is a randomized control single blinded clinical trial held in Suez canal University hospital, Obstetrics and Gynecology Department. The study was carried on 150 of pregnant women attending the emergency delivery ward and are diagnosed as cases of severe preeclampsia distributed in three groups. The first group received magnesium sulphate as a 6 gm intravenous bolus loading dose then 1 gm/hour as a maintenance dose until the delivery time, then the regimen will be continued after delivery spontaneous onset of diuresis and, greater than 50% of the hourly postpartum blood pressures less than 150 mm Hg systolic and, less than 100 mm Hg diastolic [including the hour immediately before medication discontinuation], the second group received magnesium sulphate as a 6 gm intravenous bolus loading dose then 1 gm/hour as a maintenance dose until the delivery time then the regimen continued after delivery until the onset of diuresis only and the third group received a 48 gm of magnesuim sulphate. The results showed that no cases exposed to fits in group 1 and also no cases exposed to fits in group 2; versus one case [3.3%] exposed to fits in group 3. There was only one as only one case that needed to reinitiate therapy in group 2 versus two cases needed to reinitiate therapy in group which is statistically insignificant. In group 2 there was one case needed to reinitiate therapy, so no effect on blood pressure or the need to reinitiate therapy by increasing the total dose as magnesium sulfate. There were no side effects at all from magnesium sulfate in group 1 and group 2, versus nine cases [30%] suffered from oliguria, two cases [6. 7%] suffered from hyporeflexia and three cases [10%] suffered from arrythmias in group 3. We can depend on diuresis alone as a dependable clinical parameter to withdraw magnesium sulphate safely without giving the patient unnecessary doses of the unsafe magnesium sulfate and without affecting the maternal outcome as no cases had postpartum fits and only one case needed to reinitiate therapy, although depending on diuresis and blood pressure to determine the duration of the therapy carries the same safety margin as diuresis alone and carries no more benefit over diuresis alone as magnesium sulfate not mainly an antihypertensive drug