Air trapping detected on end-expiratory high-resolution computed tomography in symptomatic World Trade Center rescue and recovery workers.

Abstract

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, and exposure-related characteristics. 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 (by two methods) and interstitial changes, and those scores were correlated with the clinical data. 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 between AT and the duration of dust exposure. AT scores were significantly higher in patients with restrictive lung function data, and in lifetime nonsmokers. 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-resolution CT scans in the investigation and characterization of the pulmonary ailments of selected workers.