Oxygen Transferring Factor (Diffusing Capacity) and its Components During Work in Patients with Chronic Obstructive Lung Disease and in Patients with Diffuse Interstitial Lung Disease

Abstract

The total diffusion capacity and its components have been determined in healthy individuals and patients with obstructive emphysema and pulmonary hypertension at rest and exercise with the steady state co-method. A minor decrease of the total diffusion capacity is observed under exercise in both groups of patients in comparison with the controls. This difference is due in the case of fibrosis to a limitation of the membrane component; in the case of obstructive emphysema and pulmonary hypertension to the blood component – in other words to a decreased capillary blood volume. Functional or anatomical restriction of the capillaries in obstructive emphysema which causes a shrinkage of the alveolo-respiratory surface for O₂-transport in the lung, explains the diminished increase of the capillary blood volume.