The Influence of Edema on the Capacity of Blood Plasma to Modify Fluid Imbibition by Muscle.

Whether edema is primarily due to changes in the blood or to changes in the fixed tissues is still an open question. Marcel Labbe and P. L. Violle (1) found that a frog's gastrocnemius muscle placed in normal human blood plasma loses from 3 to 4 per cent of its weight during the first few hours, remains constant then for about twentyfour hours, and regains its original weight at about the fortieth hour, while a muscle placed in plasma from an edematous subject, whether the edema ig of cardiac, renal, or cardio-renal origin, constantly increases in weight. That this increase of imbibition does not depend upon an increased hydrogen ion concentration of the blood is indicated by their finding that in the plasma of a patient with diabetes and marked acidosis, with pH of 6.40 and an alkaline reserve of 26 (blood taken immediately after death from diabetic coma) there was a diminution of imbibition. In a diabetic with nephritis, on the other hand, with a pH of the blood of 7.20, and an edema highly resistant to treatment, the hydrating action of the plasma on frogs ' muscle was much more marked than in other cases. They also found that muscles placed in pleural effusion fluids showed an increase of imbibition. These results support the view that the cause of edema is to be found in the body fluids rather than in the tissues. The conception that edema is due to changes in the blood is not a novel one. Before the work of Jacques Loeb (2), and the more recent work of Martin Fischer (3) which indicates that the primary cause of edema is to be found in changes within the tissues, the theory supported by Labbe 's results was accepted by many workers. We sought to duplicate the experiments of Labbe and Violle (1). Blood was taken with the precautions necessary for the determination