[Cardiac arrests probably induced by hypermagnesemia during anesthesia for caesarean section].

A 24-year-old pregnant woman was scheduled for Caesarean section during the 31st week of pregnancy. The patient had been treated with MgSO4 for premature labor and toxemia. During anesthesia, cardiac arrest occurred twice. The first cardiac arrest occurred immediately after induction of anesthesia and seemed to be due to combined effects of hypermagnesemia, thiopental and supine hypotensive syndrome. Three babies were delivered during cardiac massage. The second one occurred immediately after administration of methyl-ergometrine malate and seemed to be due to combined effects of hypermagnesemia and methyl-ergometrine malate. The patient and three babies did not develop any complication. In giving anesthesia for patients with hypermagnesemia, anesthetists should take account of interactions between magnesium, anesthetics and other drugs.