Effect of pulmonary artery occlusion upon end-tidal CO₂ tension

Abstract

Occlusion of branches of the pulmonary artery has been performed in dogs to determine its effect upon the relationship between peak end-tidal and arterial carbon dioxide tension. The use of the formula (See PDF) to express the percentage of alveolar space which is ventilated but not perfused has been tested by its application to the values encountered when one main pulmonary artery is occluded and when a smaller branch is occluded. This formula is found to express approximately the percentage unperfused. Submitted on August 15, 1958