Utility of Spirometry Values for Evaluating Tracheal Stenosis Patients Before and After Balloon Dilation.

ABSTRACT

OBJECTIVES: Tracheal stenosis is defined as a narrowing of the airway distal to the lower edge of the cricoid cartilage. It is initially diagnosed based on clinical presentation and then confirmed using direct laryngobronchoscopy. Other adjunctive diagnostic methods, including spirometry, have been proposed. This study aimed to evaluate the relationship between tracheal stenosis severity and pre- and post-balloon dilatation spirometry parameters in order to assess for significant changes in spirometry values and to evaluate for the effects of stenosis-associated factors on post-dilation spirometry values, including vertical length and grade of the stenosis, as well as the role of wound-modifying agents. METHODS: This retrospective study included adults (>18 years of age) with isolated tracheal stenosis who underwent endoscopic balloon dilations at King Saud University Medical City from June 2015 to May 2019, with detailed documentation of operative findings and valid spirometry measurements pre- and post-balloon dilation. Basic demographic data and operative note details, including information about the percentage of tracheal stenosis, distance of tracheal stenosis from vocal cords, vertical length of stenotic segment, and use of wound-modifying agents (topical mitomycin C or triamcinolone injections), were extracted. RESULTS: Fourteen patients with spirometry measurements obtained on 50 occasions (25 pre-balloon dilation and 25 post-balloon dilation) were included. Each 1-unit increase in the vertical length of the stenosis showed a statistically significant negative relationship (-1.47 L/s) with pre-balloon dilation peak expiratory flow (PEF; P = .034). Post-balloon dilation spirometric values showed statistically significant improvements for most variables. CONCLUSIONS: The vertical length of an isolated tracheal stenosis can be predicted before surgical interventions using PEF values and may be a significant indicator of anticipated post-balloon dilation surgical success. Our study suggested that spirometry is a very useful technique for evaluating patients with tracheal stenosis due to its noninvasiveness, cost-effectiveness, with a good clinical value.