Evaluation of Dyspnea Outcomes After Endoscopic Airway Surgery for Laryngotracheal Stenosis

Abstract

IMPORTANCE Endoscopic airway surgery is a frequently used procedure in the management of laryngotracheal stenosis (LTS); however, no established outcome measures are available to assess treatment response. OBJECTIVE To assess acoustics and aerodynamic measures and voice- and dyspnea-related quality of life (QOL) in adult patients with LTS who undergo endoscopic airway surgery. DESIGN, SETTING, AND PARTICIPANTS This case series compared preoperative measures and postoperative outcomes among adult patients who underwent endoscopic airway surgery for LTS from September 1, 2013, to September 30, 2015, at the tertiary care Johns Hopkins Voice Center. Patients were excluded if they did not undergo balloon dilation or if they had multilevel or glottic stenosis. The Phonatory Aerodynamic System was used to quantify laryngotracheal aerodynamic changes after surgery. Final follow-up was completed 2 to 6 weeks after surgery. MAIN OUTCOMES AND MEASURES The voice-related QOL instrument (V-RQOL), Dyspnea Index, and Clinical Chronic Obstructive Pulmonary Disease Questionnaire were completed before and after endoscopic surgery. Consensus auditory perceptual evaluation of voice, acoustic measurements, and aerodynamic outcomes were also assessed. RESULTS Fourteen patients (1 man and 13 women; mean [SD] age, 45.4 [4.3] years) were enrolled. The mean postoperative V-RQOL scores (n = 14) increased from 74.3 to 85.5 (mean of difference, 11.3; 95%CI, 2.2 to 20.3). The mean postoperative Dyspnea Index (n = 14) decreased from 26.9 to 6.6 (mean of difference, −20.3; 95%CI, −27.9 to −12.7); the mean postoperative Clinical Chronic Obstructive Pulmonary Disease Questionnaire scores (n = 9) decreased from 3.2 to 1.0 (mean of difference, −2.2; 95% CI, −3.4 to −0.9). Postoperative mean vital capacity (n = 14) increased from 2.5 to 3.1 L (mean of difference, 0.6 L; 95%CI, 0.3–1.0 L), whereas mean laryngeal resistance (n = 14) decreased from 73.9 to 46.4 cm H2O/L/s (mean of difference, −27.5 cm H2O/L/s; 95%CI, −44.8 to −10.3 cm H2O/L/s) postoperatively. CONCLUSIONS AND RELEVANCE Patients demonstrate statistically clinically significant improvement in dyspnea-related QOL, whereas a few patients showed a clinically significant improvement in V-RQOL. Dyspnea-related QOL outcomes should be added to airway surgeons’ regular assessment of patients with LTS to measure treatment response and inform the decision to perform a second operation, whereas V-RQOL outcomes need additional prospective study with a larger sample size. The Phonatory Aerodynamic System is not an optimal method to quantify changes in laryngotracheal aerodynamics after intervention in LTS.

Quality‐of‐Life Metrics Correlate With Disease Severity in Idiopathic Subglottic Stenosis

“…Idiopathic subglottic stenosis is well suited to assessment with PROMs because the primary clinical manifestation of this disease is a perceptual and psychosocial symptom with an impact on many facets of QOL . Several groups have used PROMs to show that patients with airway stenosis tend to improve along many dimensions after surgery to widen the glottis and/or subglottic airway, including along the dimensions of voice and dyspnea symptoms . Our model agrees with the inclusion of both of these dimensions, as well as including questions about cough (which can be persistent in ISGS) and general overall health.…”

“…16 Several groups have used PROMs to show that patients with airway stenosis tend to improve along many dimensions after surgery to widen the glottis and/or subglottic airway, including along the dimensions of voice and dyspnea symptoms. 9,[22][23][24] Our model agrees with the inclusion of both of these dimensions, as well as including questions about cough (which can be persistent in ISGS) and general overall health.…”

The minimal clinically important difference of the dyspnea index in laryngotracheal stenosis

“…The critical finding of the present study was that most patients with LTS reported significant postoperative improvement in dyspnea, and a DI decrease of 4 was identified as the MCID using anchor‐based methodology. The use of this statistical method, along with the higher number of patients in this cohort, may improve accuracy over previously reported MCID value . This finding is important because it provides a method to define treatment efficacy of clinical significance using a readily available PRO questionnaire.…”

“…Thus, this makes it a versatile tool that can be employed in various clinical scenarios and is easy to administer. As a recently developed PRO instrument, the DI is utilized in few published studies, and only one study by Samad et al defined the MCID of the DI as a value of 5.4 using distribution methods in this patient population . De Guzman et al identified the MCID of the DI as a decrease of 8 in adolescents with exercised‐induced PVFM .…”

“…Measures of variability include standard deviation (SD) and standard error of measurement (SEM), for which 0.5 SD or 1 SEM has been suggested to correspond to the MCID in several studies . One notable study by Samad et al used distribution methods and a 0.5 SD threshold to define the MCID of the DI in 14 patients with LTS . Based on their study, a decrease in the DI of 5.4 was calculated to be the MCID.…”