ABSTRACT
Lung function predicts not only disability but also mortality. The disability from the loss of lung function may be insignificant. Small reductions or impairments in lung function are often asymptomatic. Exercise testing on a treadmill may produce a reduction in oxygen tension in early interstitial lung disease from a variety of causes. In all chronic lung diseases, physical activity limitation is multifactorial, involving respiratory, hemodynamic, and peripheral muscle abnormalities. Measurements of lung function are commonly used to determine physiologic impairment. The measurement of static lung compliance has been suggested as a more sensitive method for evaluating restrictive lung disease in asbestos-exposed workers. British authors evaluated thin-section computed tomography to determine the extent of asbestos-induced pleuropulmonary disease and emphysema. The value of the single-breath diffusion test, when properly corrected for anemia, inspiratory breath volume, and resting carboxyhemoglobin, is that it may indicate pulmonary vascular disorders, emphysema, or early interstitial disease when the spirometry and lung volumes are normal.
