Malignant hyperthermia following systemic rewarming after hypothermic cardiopulmonary bypass

Malignant hyperthermia (MH) is a rare hypermetabolic disorder of skeletal muscle that can be fatal if not recognized and treated aggressively. We describe a patient with a suspected family history of MH who developed hyperpyrexia, acidosis, and hypermetabolism after cardiac surgery despite a nontriggering anesthetic. No drugs were identified as being causative and we theorize that systemic rewarming was the inciting cause of MH in this MH-susceptible individual via a mechanism similar to heat stroke.