A COMPARATIVE STUDY OF RED CELL VOLUMES IN HUMAN SUBJECTS WITH RADIOACTIVE PHOSPHORUS TAGGED

In recent years, total blood volume and red cell volume have become an important measurement in experimental and clinical investigation of the hemodynamics of shock, burns, hemorrhage and fluid replacement. The vital red method of Keith, Rowntree and Geraghty (1) introduced in 1915 was utilized by Robertson and Bock (2) during World War I to study blood volume in wounded soldiers. In re-cent years the Gibson and Evans (3) modification of Gregersen's T-1824 dye method has been widely used to study traumatic shock clinically (4, 5). The measurement of the red cell volume by T-1824 plasma dye is determined indirectly from the centrifuge hematocrit value. It is generally agreed by most investigators that this value overestimates the red cell volume. Chapin and Ross (6) found a positive error of 8.5 % in the centrifuge hematocrit. Gregersen and Schiro (7) showed that an average of 4.2%o of dye and plasma remained in the erythrocyte mass when blood samples containing T-1824 or Brilliant Vi-tal Red were centrifuged. Furthermore, it has been shown that the hematocrit of a peripheral vessel of the dog does not reflect the hematocrit of all of the vessels of the body (8). The results of whole blood transfusions in the treatment of shock, burns, chronic infections and other surgical problems have stimulated interest in the total red cell volume as well as in the total blood volume. Consequently, an accurate metho