Peak expiratory flow (PEF) measurements, such as dyspnea and spirometry, have been shown to be sensitive and specific predictors for the monitoring of benign tracheal stenosis. A prospective study on this subject was conducted at the Interventional Pulmonology Unit of a tertiary chest diseases hospital in Athens, Greece. Results of the analysis were published in the journal Respiration.
The investigators sought to evaluate the utility of spirometry and dyspnea in the detection of relapse of benign tracheal stenosis. Individuals with bronchoscopically proven benign tracheal stenosis who were referred for management from March 2015 through March 2019 were prospectively included in the study. Participants were assessed at regular follow-up and emergency visits via use of the Medical Research Council (MRC) dyspnea scale, spirometry, and flexible bronchoscopy. All of the patient visits were categorized and compared with respect to change in clinical and functional parameters. The patient visits were then divided into 2 groups for analysis: the case group (visits with relapse), and the control group (visits with no relapse).
A total of 35 patients were included in the current study. Most of the cases were intubation-related, with 65.7% (23 of 35) of the individuals demonstrating complete stenosis. Stenosis was detected in the middle trachea in 68.6% of participants and in the subglottic trachea in 31.4% of participants. Overall, 94.3% (33 of 35) of the patients underwent at least 1 endoscopic therapeutic session — either at their initial presentation or at their follow-up visit. Two of the patients were referred directly to surgery and were successfully treated, thus negating the need for endoscopic management either at initial presentation or at follow-up.
Relapse was reported in 72.7% of patients following the first endoscopic session, due to mucus accumulation, recurrence of stenosis, or treatment-associated complications. Overall, 14 participants underwent surgical treatment, with relapse being reported in 35.7% (5 of 14) of them. All of the individuals who experienced relapse postsurgery were eventually treated successfully with either endoscopic management or stent placement. The mean duration of patient follow-up was 3.2 years.
Analysis of spirometry data from 43 relapse visits in 23 patients vs 90 nonrelapse visits was performed. MRC dyspnea score and most spirometric indices were shown to be associated with relapse. Per the receiver-operating characteristic analysis, forced expiratory volume in 1 second, forced expiratory flow when 25% of forced vital capacity has been expired, PEF, and total peak flow were all superior to the MRC dyspnea score in predicting disease relapse. The predictive ability of the MRC dyspnea score in relapse visits due to stenosis recurrence was similar to the predictive ability of the MRC dyspnea score in the relapse visits associated with stent-related complications (area under the curve [AUC], 0.80; P <.001 vs AUC, 0.79; P <.001, respectively). Among spirometric indices, a greater than 10.8% of reduction in PEF has been shown to be very sensitive and specific.
“This study supports the role of dyspnea and spirometry in monitoring benign tracheal stenosis, with spirometry predicting relapse even in clinically stable patients. PEF being a very sensitive index has the additional advantage of being assessed by peak flow meter and could potentially be used for remote monitoring,” investigators concluded. They noted that additional studies may clarify the value of PEF measurement at home with peak flow meters for the accurate, timely prediction of stenosis relapse.
Disclosure: None of the study authors has declared any affiliations with biotech, pharmaceutical, and/or device companies.
Kossyvaki V, Anagnostopoulos N, Kaltsakas G, et al. The value of dyspnea and spirometry in detecting relapse of benign tracheal stenosis. Respiration. Published online October 6, 2021. doi:10.1159/000519216