Changes in Cell and Plasma Volumes of Various Organs Produced by a Massive Transfusion in Dogs

¹ From the Departments of Pharmacology and Physiology, Baylor University College of Medicine and University of Texas Dental Branch, Houston, Texas

Dogs anesthetized with morphine and sodium pentobarbital were killed by bleeding or with sodium pentobarbital. The control group did not receive a transfusion; the other group was given a transfusion of blood (10.0–14.9% of the body weight). The red cell volume was measured with radioactive Cr⁵¹ and the plasma volume with I¹³¹. The volume of red cells and plasma per gram of tissue and organ were calculated for: liver, spleen, kidney, heart, lung, stomach, intestine, muscle and skin. With transfusion there was an increase in the red cell volume per gram of tissue and organ except for the spleen. The liver was the primary site of trapped cells. All tissues of the transfused dogs contained more plasma than the controls. Every organ of the control dogs contained ‘extra’ plasma (that portion of the plasma free from cells); with transfusion the volume increased and represented a greater portion of the total organ blood volume. Good agreement was found between the calculation of trapped cells and plasma from blood volume measurements and by tissue analysis.