Shifts in fluid and protein with overtransfusion and hemorrhage in the dog

¹ Department of Physiology, Baylor University College of Medicine, and University of Texas Dental Branch, Houston, Texas

After control determination of red cell and plasma volume and protein concentration, seven dogs were successively overtransfused with a mean of 90 cc/kg blood, then slowly hemorrhaged to an arterial pressure of 35 mm Hg and, finally, the blood reinfused. Red cell and plasma volume and protein concentration were determined after each procedure. The bleeding volume of overtransfused dogs was larger by 11% than it was in a previously published series of dogs. However, the fraction of blood remaining in the vascular system after hemorrhage, expressed in percentage of the prehemorrhage volume for overtransfused and control dogs, was approximately the same, 66 and 61%, respectively. After the hemorrhage of overtransfused dogs, 4.6 cc/kg fluid and 2.7 g% protein left the circulation, whereas, for the control series considerable amounts of protein and fluid entered the circulation. On reinfusion, 13.9 cc/kg fluid and 4.7 g% protein left the circulation of the overtransfused dogs, a phenomenon which occurs to an even greater extent in the control group.