Role of prophylactic intravenous calcium in prevention of postspinal hypotension among women with preeclampsia undergoing cesarean delivery: a placebo controlled randomized clinical trial.

Background: Preeclamptic women, in addition to traditional antihypertensive medications, often receive magnesium supplementation and are at increased risk of postspinal hypotension Postspinal hypotension increases the risk of fetomaternal morbidity. Calcium is a physiological antagonist of magnesium in vascular smooth muscle. Therefore, the study hypothesized that calcium is better suited for preserving systemic vascular resistance and preventing postspinal hypotension during cesarean delivery.