Content of Blood and of Extravascular Water in Cat Lungs during Changes in Total Blood Volume

Abstract

AbstractA method has been developed which allows alterations in lung blood content and in extravascular lung water to be studied. The 2 upper lung lobes were removed separately from open‐chested cats. The first lobe was taken for control evaluations. The second one was removed when the circulatory situation had been changed. Labelled erythrocytes and plasma albumin had been injected beforehand. From the content of isotopes in the lung lobes, their blood volume could be calculated. Extravascular water was found by taking the difference between wet and dry weight of lung tissue, and correcting this difference for the blood content in that lobe. When total blood volume was reduced by a small bleeding, lung extravascular water content was reduced, and there was also a small reduction in lung blood volume. After a larger bleeding lung blood content was markedly reduced while the extravascular lung water content was then somewhat increased. Augmcntation of total blood volume by a blood transfusion led to an increase in lung blood volume, but to a decrease in extravascular lung water content.