Full Recovery without Complications by Early Intervention for Malignant Hyperthermia that Occurred during General Anaesthesia: A Case Series of Two Infants with Facial Anomaly

Introduction: Malignant hyperthermia (MH) is a rare and life-threatening condition characterized by muscle rigidity, hypermetabolism, and other symptoms triggered by certain anaesthetic agents. It is linked to abnormal calcium release in skeletal muscles, often associated with genetic susceptibility or musculoskeletal disorders like scoliosis. Early recognition of MH symptoms, including muscle rigidity, tachycardia, and acidosis, is crucial for prompt intervention. Here, we report two infants with successful recovery following early MH intervention during general anaesthesia.

Case Report 1: A 26-month-old male with cleft hard palate, prematurity history, and chromosomal anomaly underwent palatoplasty. Anesthesia was induced with thiopental, fentanyl, and rocuronium, followed by sevoflurane/remifentanil maintenance. During surgery, the heart rate increased suddenly with hypercapnia. Hyperthermia of 39.5°C, suggestive of MH, arose. Sevoflurane was discontinued, cooling measures were initiated, and dantrolene was administered 2 hours later. Temperature normalized, ventilation improved, and extubation succeeded. Creatine phosphokinase (CPK) level was briefly elevated to 1062 IU/L but returned to normal. Despite being suspected of having MH, the patient was discharged without any complications after one day of intensive care unit (ICU) care.

Case Report 2: A 5-month-old female with cleft lip underwent cleft lip repair surgery. She had underlying congenital heart diseases. During anaesthesia, sudden hypercapnia and hyperthermia indicated potential MH. Sevoflurane was discontinued, and ketamine, and fentanyl were used to maintain anaesthesia. Dantrolene was administered after 80 min, cooling the patient and stabilizing the hypercapnia. The surgery ended 110 min after the sudden hyperthermia. In the ICU, metabolic acidosis was managed with sodium bicarbonate. Postoperative muscle enzyme, such as CPK, levels slightly rose, then normalized. Stable recovery led to discharge after 8 days without complications.

Conclusion: In both cases, MH occurred in infants with facial anomalies and early interventions, such as dantrolene administration, for suspected MH was done. Early suspicion, supported by diagnostic tools like the MH Clinical Grading Scale, is vital.