The Relationship of Renal Blood Flow to Cardiac Output in Normal Individuals as Determined by Concomitant Radioisotopic Measurements*

AUTHORS ' YNOPSIS. Renal bloodflow and cardiac output were determined in normal men using single injection radioisotopic techniques. These methods use external monitoring to obviate the discomforts and difficult chemical determinations of older methods. The average cardiac index of 3.36 k 0.35 I./min/ma and the average renal bloodflow of 629 f 70.0 ml.lminlma compare favourably with previously reported values. Measurements of cardiac output and renal blood flow have been relatively complicated and un-comfortable clinical procedures. However, single injection techniques of radioisotopic materials for both determinations are now available and have been simplified by external counting (Pritchard