Effect of donor bronchial length on healing: a canine model to evaluate bronchial anastomotic problems in lung transplantation.

Bronchial anastomotic complications in lung transplantation in man remain a major cause of failure. To study this problem in a canine model, we varied the length of the distal bronchial component in three groups of dogs that underwent hilar stripping, bronchial transection, and reanastomosis, The distal bronchial component was thus analogous to the donor in a transplanted lung. Anastomoses were performed, respectively, at the level of the main carina (long single anastomosis), at the midpoint between the main carina and the bifurcation of the left main-stem bronchus (short single anastomosis), and just distal to the bifurcation of the left main-stem bronchus (lobar anastomosis). Bronchial anastomotic damage and necrosis were evaluated by periodic examination with a fiberoptic bronchoscope and by gross and microscopic examination at sacrifice on the seventh postoperative day. The long single anastomoses demonstrated the most necrosis, and the labor anastomoses showed the least. The short single anastomoses showed an intermediate degree of damage. These findings support the hypothesis that shortening the distal or donor bronchial component reduces anastomotic damage, probably because of better pulmonary-to-bronchial collateral blood supply. This study provides a canine model by which to examine bronchial anastomotic complicatons and demonstrates the feasibility of performing labor anastomoses as a means for decreasing bronchial anastomotic problems in lung transplantation.