THE EFFECT OF INCREASED BLOOD FLOW ON THE RATIO BETWEEN OXYGEN CONSUMPTION AND PULMONARY VENTILATION

Publisher Website
Google Scholar
Abstract
A preparation is described in which the ventilation and O absorption of each lung of a normally breathing cat may be recorded. Systemic blood pressure and pulmonary artery pressures are taken simultaneously. By occluding 1 branch of the pulmonary artery, or 1 set of pulmonary veins the total output of the right ventricle may be diverted to the contralateral lung. The usual response to the demand for increased function so produced is an increase in the respiratory minute volume. This response is slight, however, in comparison with the marked increase in O absorption which takes place. In fact, this increase takes place even when the respiratory minute volume remains the same or is actually decreased. It seems probable, therefore, that an increased blood flow in a lung, increases the functional diffusing surface. Mechanisms by which this may be accomplished are briefly outlined. Available figures concerning 0 consumption and pulmonary ventilation in human subjects during exercise are quoted and compared with the results obtained by experimentally increasing the blood flow through 1 lung of a cat.

This publication has 3 references indexed in Scilit: