Effects of methylprednisolone and azathioprine on bronchial healing following lung autotransplantation.

The effect of low-dose immunosuppressive therapy upon the healing of the bronchial anastomosis and skin wound following lung autotransplantation was evaluated. Autotransplantation was performed in two groups of dogs: Group 1 (15 dogs) received no immunosuppression and Group 2 (13 dogs) received postoperative immunosuppression with methylprednisolone (2 mg/kg) and azathioprine (1.5 mg/kg). Two to four skin incisions 7 cm in length were made in the dorsal region of each dog. Dogs were put to death at 4, 9, 16, and 23 days postoperatively and the bronchial anastomoses and skin wounds were evaluated by breaking strength measurements. Bronchus and skin breaking strength increased with time in both groups. Bronchus breaking strength was similar in the two groups at day 4 and day 9. However, by day 23 bronchus breaking strength was significantly higher in Group 1 (p less than 0.001). Skin breaking strength was significantly higher in Group 1 on days 9 and 16 (p less than 0.005) and on day 23 (p less than 0.001). Our results suggest that low-dose methylprednisolone and azathioprine significantly affect the breaking strength of both bronchial anastomoses and healing skin incisions following canine lung autotransplantation.