IMPROVEMENT OF TRACHEAL AUTOGRAFT REVASCULARIZATION BY MEANS OF FIBROBLAST GROWTH-FACTOR

Ischemic airway complications after lung transplantation remain a significant problem despite the use of bronchial omentopexy. Clinical observations suggest that enhancement of vascular ingrowth could possibly increase the efficacy of a bronchial omental flap. This study was therefore designed to investigate whether basic fibroblast growth factor can enhance blood supply of an ischemic airway by acceleration of vascular ingrowth in a rabbit autotransplant model. Segments of the trachea were harvested and transplanted into a subcutaneous pouch. The animals were randomly assigned to one of four groups: group I, no omentopexy; group II, omentopexy; group III, omentopexy and fibrin glue; or group IV, omentopexy and fibrin glue enriched with 2.5 mu g basic fibroblast growth factor. After 14 days the animals were sacrificed. The extent of perfusion was investigated by means of radioactive microspheres. The morphology of the tracheal segments was investigated in a blinded fashion macroscopically, by means of light microscopy, and by means of scanning electron microscopy. The radioactivity measurements revealed a significantly increased perfusion of group IV (77% +/- 42%) as compared with groups I (17% +/- 13%) and III (20% +/- 16%). By macroscopic and light microscopic assessment, the epithelial integrity of group IV was significantly improved compared with groups I and II. At electron microscopy the integrity of group IV was significantly superior to all remaining groups. We conclude that a deposit of basic fibroblast growth factor and fibrin glue appears to increase revascularization of an ischemic airway from omentum and thus results in improved epithelial preservation of a tracheal autograft.