The Estimation of the Volume of Blood in Normal Infants and in Infants With Severe Malnutrition

No study on fluid regulation in the body can be complete without some knowledge of the total amount of circulating fluid. Because of the large quantities of blood hitherto necessary to estimate the blood volume, few determinations have been made in infants. It was primarily with the purpose of obtaining more data on the subject that this investigation was undertaken. The method used for estimating the volume of blood was a micromodification of the method of Keith, Rowntree, and Geraghty1as improved by Hooper, Smith, Belt and Whipple.2A known amount of a nontoxic, slowly diffusible dye is injected into a vein, is allowed to circulate for a few minutes and a specimen of blood withdrawn. By determining the concentration of the dye in the plasma, the plasma volume may be calculated. The total blood volume may be computed from the hematocrit reading. In normal adults the total