Lung mechanics and frequency dependence of compliance in coal miners.
Seaton-A; Lapp-NL; Morgan-WK
J Clin Invest 1972 May; 51(5):1203-1311
The mechanical properties of the lungs were studied in two groups of coal miners, 87 miners with simple pneumoconiosis and 25 working miners with complicated pneumoconiosis. In subjects with simple pneumoconiosis, static compliance was mostly in the normal range, whereas it was often reduced in subjects with the complicated disease. The coefficient of retraction was normal or reduced in most subjects except those with advanced complicated disease, in several of whom it was elevated. So far as simple pneumoconiosis was concerned, abnormalities, when present, reflected emphysema rather than fibrosis. In severe complicated pneumoconiosis, changes suggesting fibrosis tended to predominate. In the 25 working miners dynamic compliance was measured at different respiratory rates. Seventeen of the subjects in this group demonstrated frequency dependence of their compliance, a finding unrelated to bronchitis and suggestive of increased resistance to flow in the smallest airways.
X-ray-analysis; Respiratory-function-tests; NIOSH-Author; Respiratory-system-disorders; Statistical-analysis; Airway-resistance
Journal of Clinical Investigation