[Anesthetic management for video-assisted extended thymectomy of patients with myasthenia gravis].

BACKGROUND

Thymectomy is one of therapeutic modalities for patients with myasthenia gravis. Since 1998, we have performed video-assisted extended thymectomy, which is much less invasive than traditional method. However, its optimal perioperative management has not been established.

METHODS

From April 1998 to December 2003, 40 patients with myasthenia gravis underwent video-assisted extended thymectomy in our hospital. Anesthesia was maintained with propofol, sevoflurane and epidural anesthesia. No muscle relaxant was used. Operations were performed in supine position and required differential lung ventilation of both sides in turn for manipulation. A central venous catheter was inserted in the femoral vein to prepare for unexpected bleeding or other hemodynamic changes.

RESULTS

Seven patients presented hypoxemia under differential lung ventilation and needed bilateral lung ventilation or addition of CPAP to nondependent lung. Unexpected bleeding from the left innominate vein occurred in two patients and required median sternotomy. Severe hypotension caused by compression of the heart during operation was observed in twenty-one patients. Extubation in the operating room was successful in all patients except one with severe bulbar paralysis before preoperative period.

CONCLUSIONS

It is important to examine both surgical techniques of video-assisted surgery and physiological features of myasthenia gravis for anesthetic management of video-assisted extended thymectomy.