Which perioperative exposure is most associated with precipitating malignant hyperthermia?

• A. Antibiotics
• B. Anesthesia
• C. Hyperbaric Oxygen
• D. Sedatives

Answer: (B)

Malignant hyperthermia is triggered by certain agents used during anesthesia. In susceptible individuals, volatile inhaled anesthetics (such as sevoflurane, desflurane, isoflurane, etc.) and the depolarizing muscle relaxant succinylcholine can provoke a dangerous, rapid rise in intracellular calcium in skeletal muscle. This causes a hypermetabolic state with rapid heat production, excessive carbon dioxide, tachycardia, muscle rigidity, acidosis, and potential organ damage if not treated promptly. Because the perioperative exposure that most reliably precipitates MH is the anesthesia itself, this makes anesthesia the best answer. Other options—antibiotics, hyperbaric oxygen, and sedatives—are not the classic triggers for malignant hyperthermia.