Effect of heparin on inflammation: an animal model of tracheal stents.

Objectives/Hypothesis: The objective of this study was to investigate the effect of systemic heparin on tracheal and wound healing. Study Design: An animal experiment using a tracheal stent model. Methods: Twenty Wistar albino rats were divided into two groups; a heparin group (n=10) that received 210 U/kg/d heparin sodium, and a saline group (n=10) that received 0.1 mL of 9% NaCl. Stents of 1 cm in length made of 8F feeding tube were placed into the tracheas of rats in both groups and stayed in place for 10 days. Ten days after removal of the stents, the rats were sacrificed and the tracheas were harvested. Histological evaluations of the tracheas were performed with respect to inflammatory parameters. Results: We observed significantly milder inflammation in the heparin group compared to the saline group in terms of inflammatory cell count, fibroblastic proliferation, edema, and vascularity at the site where the tracheal incision was made (P<.05). Inflammation tended to be of a lesser extent in the stent site in the heparin group (P>.05). Conclusions: We could demonstrate that heparin does inhibit fibroblast proliferation, inflammatory cell count, edema, and angiogenesis in this animal model. We believe that future studies can elucidate on laryngotracheal wound healing as well as their molecular mechanisms.