Abstract:

Objective   To establish an animal model to study the changes of tracheal mucociliary transport before and after trachea reconstruction, in which a 6.5 cm segment of cervical trachea was replaced by jejunal autograft with partially scraped mucosa. Methods   Eight beagle dogs were included in the study. A 6.5 cm segment of cervical trachea was resected. Through a midline abdominal incision, 7 cm jejunum was resected and the graft was prepared by scraping partial mucosa off with surgical knife and dry gauze. Microvascular anastomoses were done between the mesenteric artery and the right common carotid artery, using a standard end-to-side technique. The mesenteric vein was anastomosed with the right common carotid vein, using a standard end-to-end technique. The silicone stent was placed in the lumen of the jejunal segment and  removed  four week later after the operation. A Ni-Ti alloy prothesis was placed over the jejunal segment, with the mesenteric vessels passing through the longitudinal opening of the mesh tube. In every canine model, the position of lower margin of resected trachea was marked in cervical skin  and 50% barium sulfate mucilage was injected as a tracer into the trachea lumen under fiberoptic bronchoscopy. The time between the injection and arrival of tracer to  glottis (mucociliary transit time, MTT) and corresponging length of travel  (mucociliary transport length, MTL) were recorded. Mucociliary transit rate (MTR), as MTL/MTT, was calculated. The same procedure was performed before operation and 7 days, 1 month and 3 months postoperatively. Statistical analysis was performed. Results   There was no difference in MTR before operation and 1 month, 3 months after operation, and there was also no difference in MTR between 1 month and 3 months postoperatively(P＞0.05). Statistical significance in MTR were noted between all the neighboring two time points, from preoperative MTR, 1 week , 1 month and 3 months  postoperative(P<0.05). Conclusion   In the tracheal reconstruction by jejunal autograft with partially scraped mucosa, MTR is to be normal 1 month later after the operation. MRT at 3 months postoperative remains equally with the preoperative or 1 month postoperative.

Key words: Trachea, Transplantation, autologous, Jejunum, Mucociliary clearance