[Postoperative thyrotoxic crisis during beta blockade: an atypical picture of generalized muscle deficiency]

The case is reported of a 42 year old female patient with Graves disease who presented with an atypical thyroid storm after subtotal thyroidectomy. Surgery was indicated because of poor patient compliance with the medical treatment, and its partial failure. High doses of propranolol (240 mg a day) were given for 5 days preoperatively. Anaesthesia and surgery were uneventful however, towards the end of the first postoperative day, a severe myopathic syndrome started, with neither fever nor tachycardia. Respiratory failure and pneumonia occurred 24 h later. This was deemed to be due to an atypical thyroid storm. The patient was intubated and ventilated, and treated with high doses of propranolol (320 mg a day). Muscle strength began returning to normal on the 4th postoperative day, being completely normal 2 months later. Even though a particularly severe form of thyrotoxic myopathy appeared to be the most likely cause of this temporary muscle disorder, beta-blockers may have been involved. Their potential role is discussed.