Airway anastomotic healing in the rat tracheal autograft

The healing of airway anastomoses after tracheal autotransplantation was studied in a rat model. Tracheal autotransplantation in length of five tracheal cartilaginous rings was performed in 46 PVGr1 female rats. The animals were sacrificed and divided into six groups as follows: 0-day control group, and 3-, 7-, 14-, 21- and 28-day study groups (n = 6-7/group). In laser Doppler measurements, blood flow was significantly increased in the lower anastomosis after day 7 and in the upper anastomosis after day 21 compared with the control group (p < 0.05). The breaking strength of the tracheal autograft increased after day 7 compared with the control group (p < 0.05). The total collagen content of the lower anastomosis was significantly decreased on days 3 and 7 compared with the control group (p < 0.05), but thereafter it increased constantly. In the upper anastomosis on days 3 and 7, there were significant histological alterations, especially in the tracheal epithelium, compared with the control group (p < 0.05). Tracheal anastomosis is most vulnerable during the first 7 days.