Effect of Splenomegaly on Blood Volume

Abstract

Simultaneous red cell and plasma vol. detns. utilizing P32 tagged erythrocytes and I131 labeled human serum albumin were obtained in patients with marked splenomegaly. The mean ratio, total body relative cell vol./peripheral hematocrit value, was 1.035, compared to a mean vol. of 0.943 in control subjects. None of the control subjects had a ratio greater than 0.979. Five of the 7 patients had ratios ranging from 1.01 to 1.12. This observation is interpreted as consistent with an increase in the vol. of cell-rich blood in the spleen in cases of splenomegaly. The mixing time of tagged red cells may be significantly prolonged in subjects with splenomegaly.