Malignant hyperthermia syndrome in an anxious patient.

A 30-yr-old patient with fulminant ulcerative colitis was anaesthetized on three occasions, for colectomy and rectal stump removal. The first anaesthesia, with droperidol and fentanyl and pancuronium neuromuscular block, was uneventful. Addition of suxamethonium on the second occasion and use of the original drugs plus nitrous oxide for the third anaesthesia produced symptoms of MH, which was confirmed by muscle biopsy. There was no hyperthermia. The patient's admitted anxiety before the last two operations is believed to have played a role in the genesis of MH.