Air Trapping Detected on End-Expiratory High-Resolution Computed Tomography in Symptomatic World Trade Center Rescue and Recovery Workers

Objectives: We utilized end-expiratory chest computed tomography (CT) to investigate air trapping (AT) in symptomatic former World Trade Center (WTC) workers, and correlated the findings with clinical, physiological, a exposure-related characteristics. Methods: Twenty-nine WTC workers with lower respiratory symptoms were evaluated. Clinical data included symptom inventories, quantitative respiratory symptom scores, WTC dust exposure duration, pulmonary function tests, and inspiratory and end-expiratory high-resolution chest CT scans. The latter were scored quantitatively for AT (b two methods) and interstitial changes, and those scores were correlated with clinical data. Results: The two AT scoring methods yielded highly correlated results. AT was demonstrated in 25 of 29 patients, with scores ranging from 0 to 24 (mean, 10.6). There was a statistically significant correlation betwee AT and the duration of dust exposure. AT scores were significantly higher patients with restrictive lung function data, and in lifetime nonsmokers. Conclusions: Our data suggest that AT from small airways disease may account for some of the reported clinical and pulmonary functional abnormalities in WTC dust-exposed workers, and support the use of high-resoluti CT scans in the investigation and characterization of the pulmonary ailments of selected workers.