Perioperative management of neuroleptic malignant syndrome in a schizophrenic patient scheduled to undergo operation for bowel obstruction

Neroleptic malignant syndrome (NMS) is a serious side effect of antipsychotic medications. The risk factors for NMS are the patient's physiologic conditions such as dehydration, malnutrition, stress, and additional administration of sedative drugs including haloperidol. We report a case of 62-year-old schizophrenic man with bowel obstruction due to rectal cancer. Colostomy under general anesthesia was scheduled, and he had not taken oral medication. After intravenous injection of haloperidol for sedation, muscle rigidity, high fever, and an elevated serum level of creatine phosphokinase were observed. He was diagnosed as NMS, and sodium dantrolene was administered. After the improvement of NMS, colostomy was done. Dehydration and malnutrition of the patient were severe at the time of operation, and the possibility of NMS developing due to stress was thought to be very high. We administered sodium dantrolene to prevent NMS after the operation, and the management for prevention of NMS is discussed.