Case report: clearance to dive for a naval candidate with family history of malignant hyperthermia.

Introduction: A 20-year-old male military recruit who presented for a screening physical for U.S. Naval Diving Duty was found to have family history significant for malignant hyperthermia. He had never been exposed to anesthesia, a trigger for the condition, and had not undergone testing. Medical history was otherwise unremarkable, and the patient was cleared for diving. Methods: Literature search was conducted using Pub-Med/Medline. Keywords included malignant hyperthermia, exertional heat illness, exertional rhabdomyolysis, diving, special operations, military. Results that included cases of malignant hyperthermia were included. Results: Review of the literature reveals that malignant hyperthermia is primary a pharmacogenetic disorder limited to specific anesthetics, with rare reports of environmental triggers. Analysis of the disease, as well as the absence of reported cases of malignant hyperthermia in diving, suggest there is minimal increased risk in diving for subjects without history of exercise intolerance. Conclusion: Individuals with presumed or proven malignant hyperthermia susceptibility seeking activity clearance should be given precautions and undergo careful questioning for history of heat- or exercise-related illness. If negative, it seems reasonable to allow the patient participation in recreational or technical diving.