Collagen coated Y-shaped prosthesis for carinal replacement promotes regeneration of the tracheal epithelium.

Carinal reconstruction has the highest operative mortality rate in pulmonary surgery, and high tension at the anastomoses is one of the reasons. We have reported previously that a new Y-shaped artificial trachea gives acceptable short-term results. Here, we report our long-term observations and histologic findings. A Y-shaped Marlex mesh tube reinforced by a polypropylene spiral was coated with collagen, which was extracted from porcine skin, to increase the biocompatibility and airtightness of the prosthesis. Replacement of the carina was performed in 20 beagle dogs. The prosthesis was covered by the omental pedicle in all dogs. Six of the 20 dogs survived past 6 months, and 4 were in good condition when they were killed. The other 13 dogs died within 11 days of the operation. The main cause of death was air leakage from the prosthesis. Bronchoscopic examination of the surviving dogs 12 months after surgery revealed that the prosthesis was covered with regenerated tissue, and neither stenosis nor dehiscence was recognized; 15 months after implantation microscopic examination showed the growth of ciliated epithelial cells over the lumen of the prosthesis. These results suggest that our Y-shaped artificial trachea might be useful for reconstruction of the carina with tissue regrowth, although some improvement of the prosthesis is necessary.