Malignant Hyperthermia: Clinical Management

Abstract

Malignant hyperthermia is a subclinical myopathy in which general anesthesia triggers an uncontrollable contraction of skeletal muscle that leads to a life-threatening hypercatabolic state and an increase in body temperature. The disease is primarily autosomal dominant; mutations in receptors (especially ryanodine receptor type 1) predispose to volatile anesthetic agents or succinylcholine causing an accumulation of intracellular calcium in skeletal muscle that leads to its overactivation and hypermetabolism. In the acute setting, diagnosis is based mainly on clinical presentation and end-tidal capnography, which reveals an increase in end-tidal CO2. Initial treatment measures include discontinuation of the agent causing the reaction and administration of dantrolene. In non-acute settings, there are specific diagnostic tools such as the caffeine-halothane contracture test to confirm suspected cases. MH is a lethal disease and has a high mortality rate if not treated early.