Swallowing outcomes after tracheal resection and anastomosis: full versus mini infrahyoid laryngeal drop.

Introduction: Tracheal resection anastomosis has been established as the definitive surgery for high grade postintubation subglottic stenosis. To achieve a relaxed tension-free anastomosis, various laryngeal release techniques were discussed in literature with potential effect on postoperative swallowing dysfunction. This study aims to compare the difference in swallowing outcomes following two methods of infrahyoid laryngeal release: with and without fracture of the superior thyroid horns.

Methods: A retrospective cohort study was carried out at our tertiary referral hospitals including cases with grade III and IV subglottic stenosis treated by partial crico-tracheal resection with thyro-tracheal anastomosis. The patients were divided into two groups according to the method used in laryngeal release; mini infrahyoid release (group A) or infrahyoid full release (group B) where full means with fracture of the superior thyroid horn bilaterally while mini means their preservation. Swallowing assessment preoperatively and postoperatively was done by comparing swallowing dysfunction symptoms, Gugging swallowing screen (GUSS) score and fiberoptic endoscopic evaluation of swallowing (FEES) according to penetration aspiration scale (PAS).

Results: A total of 71 patients were included; 46 in Group A and 25 in Group B. Clinical swallowing evaluation one week postoperatively showed statistically significant difference between the two groups being affected in 80.04% and 100% of patients in group A and B, respectively. The mean postoperative GUSS were 18 ± 1.32 in group A patients in comparison to 8.84 ± 5.18 in group B (p-value < 0.001). With FEES assessment, group A had full improvement of their swallowing abilities one month after the surgery while patients in group B had significantly lower PAS scores. Unfavourable scores for both the GUSS test and PAS were associated with increasing patients' age in group B.

Conclusion: In this retrospective cohort study, cases with mini infrahyoid laryngeal release had significantly better swallowing outcomes and full resolution of dysphagia in comparison to full laryngeal release. Also, full laryngeal release is associated with delayed resolution of swallowing difficulty in older patients. This point should be considered during preoperative patient selection and counselling.