Clinical Determination of Renal Function by an Index of Urea Excretion

During the past few years, qualitative and quantitative studies of renal excretory activity, or so-called kidney function, have been carried out in a number of ways. These studies have been directed, on the one hand, either toward an estimation of elimination in the urine by the kidney of substances which it excretes normally, or toward the study of the ability of the kidney to excrete foreign substances artificially introduced into the body. On the other hand, there have been numerous studies of the blood in the various forms of disturbed renal function. For the study of excretion of foreign substances, various dyes have been used. Most important of these is phenolsulphonephthalein, introduced into clinical use by Rowntree and Geraghty.1The method consists in the intravenous or intramuscular administration of the dye, and the colorimetric determination of the amount recovered in the urine in a standard length of time. Its