Acceptable Warm Ischemia Time of Tracheal Grafts From Non–heart-beating Donors in Rats

Objectives. Warm ischemia (WI)-induced airway complications are common in clinical lung transplantation. However, the acceptable WI time of tracheal grafts from non-heart-beating donors (NHBDs) is unknown. The purpose of this study was to determine the acceptable WI time by observing tracheal epithelial regeneration among NHBD. Method. Forty-eight rats were randomly divided into four groups (each with 12 rats): WI-0 minutes (group A), WI-30 minutes (group B), WI-45 minutes (group C), and WI-60 minutes (group D). In each group, the tracheas from 6 rats were imbedded in the greater omentum of 6 other rats. Fourteen days later, the transplanted trachea was obtained from the recipient to evaluate epithelial thickness and regeneration. Six tracheas were obtained from living donors as a control group. Results. There were no significant differences in tracheal transplantation time (mean, 17.66 +/- 1.21 minutes). There were no significant differences in epithelial thickness and regeneration between the controls and groups A, B, and C (P<.05). Group D showed no normal epithelial structure of the trachea only with monolayer cells. Conclusions. The time limits of tolerance to WI of tracheal grafts from NHBDs may be 45 minutes.