Pathophysiology
Clinical meaning
Malignant hyperthermia (MH) is a rare, inherited, life-threatening disorder triggered by certain anesthetic agents, most commonly succinylcholine and volatile inhalational anesthetics. In susceptible individuals (autosomal dominant mutation in the ryanodine receptor gene RYR1), these agents cause uncontrolled release of calcium from the sarcoplasmic reticulum into the muscle cell cytoplasm. This triggers sustained skeletal muscle contraction and hypermetabolism, producing excessive heat, carbon dioxide, and lactic acid. Without rapid intervention, the condition progresses to rhabdomyolysis, hyperkalemia, metabolic acidosis, and cardiac arrest. The nurse must recognize early warning signs, assist with emergency interventions, and report changes in the patient's condition immediately.