Prevention of laryngotracheal stenosis with pirfenidone after tracheotomy: An experimental study on rats

ABSTRACT Laryngotracheal stenosis(LTS) is an important pathology which occurs after prolonged intubation and tracheotomy. In these cases, many treatment methods are tried but have no clear success, so physicians are turning to new treatment modalities. In this study, Pirfenidone's role about reducing tracheal stenosis by suppressing fibrosis and inflammation was examined. Tracheotomy was performed on 14 rats and their cannulas were fixed to tracheotomy area by stoma suture. Two working groups were established. Rats in first group were given 1 mg/ml/day Pirfenidone intraperitoneally for 10 days. In the second group as a control group, 1 ml saline solution was applied intraperitoneally. 10 days after, rats were decanulated and kept alive 3 more weeks. Anesthetized rats were sacrificed on day 30. All of the rats' tracheas were resected between 1st and 7th rings. Epithelial damage, inflammation, fibrosis were determined histopathologically, diameters of intra-tracheal lumen and theirs mucosal thickness parameters were determined histomorphometrically and TGFβ-1, TNFα and IL-1β values were determined immunohistochemically. According to the parameters of the control group, Fibrosis, diameters of intra-tracheal lumen and values of TGFβ-1, TNFα and IL-1β were found to be statistically significant. In our study, it was found that Pirfenidone reduces fibrosis and narrowing of intra-tracheal lumen diameter significantly. Keywords: Laryngotracheal stenosis ∙Tracheotomy∙Pirfenidone