Growth of tracheal autografts in puppies.

The growth of tracheal autografts and the patency of anastomotic regions were studied in 11 mongrel puppies (2.5-4 months of age, 1.9-4.3 kg in weight). Thoracic tracheal autotransplantation of 7 cartilage rings was performed. The tracheal autografts and anastomotic regions were covered with an omental pedicle flap to facilitate revascularization. Seven of the 11 dogs were evaluated for 12 months. The cross-sectional area of the lumen at the center of the tracheal autograft, as measured by thoracic computed tomography (CT), showed a significant increase from 0.37 +/- 0.11 cm2 to 1.13 +/- 0.44 cm2 after 12 months (P < 0.05). At 12 months postoperatively, all of the experimental dogs were killed, their entire tracheas were resected, and the cross-sectional areas of the anastomosis on the proximal and distal sides were measured. The cross-sectional areas at sites 5 mm apart from both anastomoses in the ungrafted trachea were measured as controls. The percent cross-sectional area (%CSA) showed good values of 67.2% +/- 19.6% on the proximal side and 85.1% +/- 12.6% on the distal side. The tracheal autografts appeared both visually and histologically viable 12 months postoperatively. This study was able to demonstrate the growth potential of the tracheal autograft in a growing puppy model.