Management of Severe Maternal Hyponatremia Secondary to Pre-Eclampsia

Objective: Severe maternal hyponatremia is a rare complication of preeclampsia in pregnant patients with a range of proposed etiologies including syndrome of inappropriate antidiuretic hormone and low effective circulating blood volume causing an increase in antidiuretic hormone

Case Report: A 32-year-old G1P0 presented at 35 weeks’ gestation to her primary obstetric provider with mild range blood pressures and an incidental sodium level of 123mEq/L. The patient was diagnosed with preeclampsia with an atypical severe feature of hyponatremia. When her sodium nadired to 118mEq/L, anesthesia, neonatology, and renal specialists huddled to discuss the risks of delivery. She ultimately developed a non-reassuring category 2 fetal heart pattern and was delivered by cesarean section. Postoperatively, her sodium rapidly normalized with minimal intervention.

Conclusion: Maternal hyponatremia is a rare though serious complication of preeclampsia that warrants close inpatient management and a balance of maternal, neonatal, and obstetric considerations.

Keywords: Hyponatremia; Pre-eclampsia; Perioperative Obstetric Care