Ellen Brown

RED CELL, PLASMA, AND BLOOD VOLUME IN HEALTHY WOMEN MEASURED BY RADIOCHROMIUM CELL-LABELING AND HEMATOCRIT*

In a previous study of 201 healthy men (1), red cell volume (Vrbc) was measured by a modification of Sterling and Grays radiochromium method (2), and whole blood and plasma volumes (Vwb and Vpl) were derived from venous hemiatocrits. The influence of factors other than body size on the variance of the data was studied, and standards for predicting normal volumes were derived. The present report describes a similar examination of 101 women.

Red cell, plasma and blood volume in healthy men measured by radiochromium (Cr51) cell tagging and hematocrit: influence of age, somatotype and habits of physical activity on the variance after regression of volumes to height and weight combined.

Methods employing radioactively tagged red cells have been widely adopted for measurement of blood volume. However, in comparison with the work which has been done with the dye (1-5) and carbon monoxide (6) methods, little attention has been given to the establishment of mean values for men and women or to study of the variance encountered among healthy subjects. Most clinical investigators have collected their own control data, based often on study of relatively few or not entirely healthy subjects (7-13). A rather large scatter of data around mean prediction values has been found by all workers, regardless of methods employed, when values for whole blood volume (Vwb), red cell volume (Vrbc) and plasma volume (Vpl) are related to body weight, height, or combinations of these measures (1-5, 13, 14). Some of this variation presumably results from differences in body composition, since blood volume correlates both with body density (5, 15) and with lean body mass (16, 17). However, it has not been shown that predictions based on total body mass are less accurate than those based on lean body mass, which requires a separate measurement (15, 16). Consideration of fat thickness and girth measurement, in addition to height and weight, was found by

Distribution of CO and Radiochromium in Blood and Tissues of Rabbit and Dog. I. Carbon Monoxide.

Summary 1. Carbon monoxide gas and autogenous red cells tagged with Cr51 were administered simultaneously to rabbits and to dogs. Blood and homogenized tissues from various organs were analyzed for radioactivity and for CO content. 2. The volume of distribution of CO was 13% larger than the volume of distribution of Cr51 in the rabbit. The discrepancy is the same as that found in man and the splenectomized dog. 3. CO accumulated in red skeletal muscle and myocardium in amounts sufficient to account for the discrepancy between distribution volumes. 4. Evidence was found pointing to slight accumulation of Cr51 in spleen and lung. Further studies of this phenomenon are described in part II of this report.

Distribution of CO and radiochromium in blood and tissues of rabbit and dog. II. Radiochromium.

Summary 1. Carbon monoxide and autogenous red cells labeled with Cr51 were administered simultaneously to dogs and rabbits; tissue homogenates and blood were then analyzed for radioactivity and CO content. 2. Small amounts of Cr51 accumulated regularly in spleen and lung and, when the cells were delivered via the portal vein, in the liver. No sequestration occurred in brain, kidneys or extremities. 3. Prolonged storage of tagged cells, particularly when suspended in saline rather than plasma, increased the loss of Cr51 from the cells in vitro and by early sequestration after injection of the cells into their donors. 4. When cells were stored in saline for only 1 day, combined losses caused by in vitro leakage and sequestration were too small to influence the results of blood volume determinations.