Malignant hyperthermia: an OR emergency!

Malignant hyperthermia (MH) is a hypermetabolic syndrome triggered in genetically susceptible individuals when certain potent inhalation anesthetics or succinylcholine are administered. The signs of MH include a greatly increased body metabolism, muscle rigidity and eventual hyperthermia that may exceed 110 degrees F. Death can result from cardiac arrest, brain damage, internal hemorrhaging or failure of other body systems. Dantrolene is given until the manifestations of MH abate. The initial dose is 2.5 mg/kg body weight; and repeated as needed. High-risk patients cannot always be identified by history, and preparation of every OR is essential. Supplies of dantrolene and other medications must be kept in the OR area. If MH develops, acting within minutes may save a life.