Unmasking malignant hyperthermia: a rapid response to a hypermetabolic crisis: case report

Introduction Malignant Hyperthermia is a rare, life-threatening pharmacogenetic disorder that can occur after exposure to triggering anesthetic agents, including volatile anesthetics and succinylcholine. Case presentation An 18-year-old male with multiple traumatic fractures underwent orthopedic surgery under general anesthesia with succinylcholine and sevoflurane. Approximately three hours after induction, he developed acute hyperthermia 39.4 °C (103°F), tachycardia (120–130 beats/min), and hypercarbia with end-tidal CO₂ reaching 58.5 mmHg. Intervention Malignant hyperthermia was suspected intraoperatively. Triggering agents were discontinued, total intravenous anesthesia was initiated, 100% oxygen was administered, active cooling measures were applied, and intravenous dantrolene 260 mg was given, corresponding to approximately 2.5 mg/kg. Outcomes The patient demonstrated rapid improvement in in temperature and normalization of end-tidal CO₂ after dantrolene administration. He was transferred to the intensive care unit intubated and sedated, received additional dantrolene dosing, was extubated the following day, and ultimately recovered without recurrent malignant hyperthermia symptoms during subsequent surgery after total intravenous and regional anesthesia. Conclusion This case highlights the importance ofperioperative vigilance, rapid intervention, and careful differentiation from other hypermetabolic crises. Early recognition, discontinuation of triggering agents, and prompt administration of dantrolene are essential to prevent morbidity and mortality in malignant hyperthermia.