Isoflurane for thymectomy in myasthenia gravis

The clinical and electromyographic effects of isoflurane were studied in eight myasthenic patients undergoing trans-sternal thymectomy. After inhalational induction of anaesthesia, intubating and operating conditions were good. Recovery from anaesthesia was rapid with minimal postoperative residual muscle weakness or respiratory depression. All patients were extubated within the first postoperative hour. Integrated electromyographic monitoring of the train-of-four response of adductor pollicis demonstrated that myasthenics are more sensitive than nonmyasthenics to the neuromuscular depressant effects of isoflurane. Recovery of the integrated electromyographic response was incomplete despite a satisfactory clinical recovery.