[Carbon dioxide tension gradients in patients with chronic nonspecific lung diseases].

The results of studying carbon dioxide tension at different structural levels of gas exchange in 447 patients with chronic nonspecific pulmonary diseases and in 845 normal subjects indicate that in patients, CO2 tension in mixed venous blood increases less than in the arterial blood as a result of which the venoarterial gradient diminishes considerably. The venoarterial and arterioalveolar gradients of CO2 tension increase as the gravity of respiratory failure rises.