Absence of postoperative hyponatremia syndrome in young, healthy females.

Young and previously healthy females have been reported to develop severe postoperative hyponatremia with a fatal outcome. The clinical presentation is dramatic, with seizures, respiratory arrest, and permanent, often catastrophic, brain damage. The true incidence is unknown. We report a survey of 290,815 surgical procedures on females at the Mayo Clinic from 1976 to 1992. Postoperatively 1,498 females had cardiopulmonary arrest, 255 had a metabolic encephalopathy, 32 had new-onset seizures, and 6 had central pontine myelinolysis. We failed to identify any association of respiratory arrest with postoperative hyponatremia. Our findings indicate that the postoperative hyponatremia syndrome in young, healthy females with respiratory arrest is extremely uncommon.