[Pulmonary gas exchange during isovolaemic haemodilution (author's transl)]

In experiments on 6 closed chest dogs the behaviour of pulmonary gas exchange during isovolaemic haemodilution with 6% dextran was studied. The dogs were ventilated artificially using an inspiratory gas mixture containing 25% O2. A slight increase of arterial Po2 values was found. This change was accompanied by a decrease in alveolar-arterial Po2 and Pco2 gradients. The size of effective pulmonary capillary blood flow varied in accordance with the size of cardiac output. The changes of pulmonary O2 diffusing capacity could be explained by the effect of haemodilution per se.