Delayed Postoperative Malignant Hyperthermia After Total Intravenous Anesthesia: A Case Report.

Malignant hyperthermia (MH) is a rare pharmacogenetic disorder typically triggered by volatile anesthetics or succinylcholine, but its occurrence after total intravenous anesthesia (TIVA) remains exceptional and underreported. Propofol-based TIVA is recommended for MH-susceptible patients to avoid known triggers, yet absolute prevention cannot be guaranteed. A 24-year-old male with prior suspected MH underwent spine surgery under propofol-remifentanil TIVA after strict preventive preparation. Despite stable intraoperative parameters, he developed fever, tachycardia, rigidity, and myoglobinuria 14 hours postoperatively, with markedly elevated creatine kinase and myoglobin levels. Dantrolene administration resulted in rapid clinical improvement. The Malignant Hyperthermia Clinical Grading Scale score of 48 indicated "very likely MH." This case underscores the risk of MH even with TIVA in susceptible patients, emphasizing the need for vigilant monitoring, availability of dantrolene, and preparedness for delayed onset regardless of the anesthetic technique used.