Is magnesium sulfate therapy warranted in all cases of late postpartum severe hypertension? A suggested approach to a clinical conundrum

Abstract

Magnesium sulfate reduces the risk for eclamptic seizures antepartum, intrapartum, and in the immediate postpartum period, however, there are no studies that have evaluated the benefits and risks of magnesium sulfate among women with late postpartum severe hypertension only. Juxtaposed on this clinical uncertainty is the increased incidence of severe hypertension owing to a rise in pregnancies complicated by advanced maternal age, obesity, chronic hypertension, diabetes, and recent protocols for intensive monitoring of blood pressure in the postpartum period. These factors have led to a significant increase in postpartum presentations for the evaluation and management of severe hypertension, in some cases leading to postpartum readmissions for administration of antihypertensive therapy and magnesium sulfate without data demonstrating clear clinical benefit. Postpartum readmissions can have several negative consequences, including interfering with early bonding with a newborn, breastfeeding, and use of scarce healthcare resources. In addition, magnesium sulfate is associated with risks for serious cardiorespiratory depression and bothersome side effects and can delay determining the optimal antihypertensive regimen, which is typically the most pressing clinical need during postpartum presentations of late-postpartum severe hypertension. Eclampsia that occurs more than 48 hours after delivery is rare (constitutes 16% of all cases of eclampsia) and is most commonly preceded by headaches or other cerebral symptoms. In this commentary, we propose an approach to evaluating and managing patients with late postpartum severe hypertension aimed at identifying those women at highest risk for end-organ injury. We recommend that the short- and long-term focus for all patients with severe hypertension should be the optimal management of blood pressures with a goal of close outpatient monitoring when logistically feasible and clinically appropriate. We suggest reserving magnesium sulfate therapy for the subset of patients with neurologic symptoms who may be at highest risk for an eclamptic seizure.

Keywords: HELLP syndrome; antihypertensives; diuretics; eclampsia; end-organ injury; furosemide; headache; magnesium sulfate; postpartum hypertension; preeclampsia; readmission; seizure.