Extended thymectomy in patients with myasthenia gravis with high thoracic epidural anesthesia alone

Successful extended thymectomy was performed in three patients with myasthenia gravis under only high thoracic epidural anesthesia with voluntary breathing. It was not necessary to intubate a tracheal tube during operation for any of the patients. Neither muscle relaxants nor volatile anesthetic agents were required. The mean operating time was 2.0 +/- 0.5 hours. The drainage tubes were removed the day after operation in all patients. In two patients the arterial oxygen saturation (SaO2) and the arterial partial pressure of carbon dioxide (PaCO2) and oxygen (PaO2) were stable; in the third patient the SaO2 was temporarily decreased to 92 mmHg when bilateral mediastinal pleura were opened. The right pleural defect was then covered with a large wet towel, which was pressed on the defect, and thoracic drainage was performed. The left pleural defect was repaired with 3-0 Vicryl after suctioning the air in the pleural space, after which the SaO2 recovered. All patients were able to drink water and walk within 1 hour after the operation. This procedure is advantageous in that the use of muscle relaxants and volatile anesthetic agents prevented the laryngeal injury that results from translaryngeal intubation; in turn we avoided causing postoperative respiratory insufficiency. This may be suitable for the operation of some patients with MG, but further studies are required to define the indication.