Reconstruction of large tracheal defects in a canine model: lessons learned

Tracheal reconstruction remains a major clinical problem owing to the need for rigid support and a lining to maintain a patent lumen. The purpose of this study was to investigate the feasibility of microsurgical tracheal reconstruction in large animals. Two-stage tracheal reconstruction was attempted in six dogs and single-stage reconstruction in eight dogs. In the first-stage prelamination, tubular prosthetic material was lined with an abdominal fascial flap with skin grafting and covered with a rectus abdominis muscle flap. The construct was buried under the abdominal skin for 3 weeks, and then microsurgical tracheal reconstruction for a 6-cm-long defect was performed. Prosthetic materials tested were PolyMax mesh (Synthes, Paoli, PA), polytetrafluoroethylene graft, and polytetrafluoroethylene graft stented with PolyMax mesh. In single-stage reconstruction, supporting materials were lined with an abdominal fasciocutaneous flap for microsurgical reconstruction. Supporting materials included polytetrafluoroethylene graft stented with PolyMax mesh, polypropylene mesh with ring support, and cross-linked urinary bladder matrix. First-stage prelamination failed in three dogs because of prosthetic collapse and infection. Second-stage reconstruction was performed in the other three dogs, but fatal complications occurred in the immediate postoperative period. In single-stage reconstruction, prosthetic failure remained the major problem, resulting in early deaths. Air leakage and difficulties in providing postoperative care for dogs were other factors limiting long-term survival. We encountered significant prosthetic failures and difficulties in postoperative care in dog tracheal reconstruction. Further research is needed to develop better supporting materials. Alternative animal models may be sought to minimize complications.