Measuring central airway obstruction: What do bronchoscopists do?

Rationale: All bronchoscopists will encounter, at some point, central airway obstruction (CAO) and will face the problem of documenting its severity. Axial imaging is suggested as the gold standard for assessing CAO, but anecdotal evidence indicates that many bronchoscopists use visual estimation. The prevalence and reliability of this method have not been extensively studied. Objectives: This study aimed to determine bronchoscopists' opinions about assessing CAO and to assess the variability of visual estimation. Methods: All 438 members of the American Association of Bronchology and Interventional Pulmonology were invited to participate in an online questionnaire. In addition to reporting opinions and practice in measuring CAO, participants estimated degree of obstruction for 10 bronchoscopic photos of abnormal central airway lesions using a sliding scale from 0 to 100%. Measurements and Main Results: Responses were obtained from 118 individuals with varied interventional bronchoscopy experience. Most participants reported using visual estimation of CAO (91%) and largely by numeric estimates (87%). A total of 55 participants volunteered additional methods they employed, and their comments reflected discontent with the dependability of those. When shown the same 10 bronchoscopic photos, estimates varied considerably, with very large ranges of responses for all images. Most (86%) agreed that measurement of airway narrowing should be standardized. Conclusions: Although limited by sample size and static photos of abnormal airways, this study supports the tenet that most bronchoscopists use a subjective and variable method of estimating CAO, which is anecdotally pervasive in the absence of a clinically practical alternative.