A comparison between the changes in the distribution volumes of inulin and [51Cr]EDTA after major surgery.

In 12 patients undergoing major surgery the distribution volumes of inulin (V1) and [51Cr]EDTA (V-E) were measured simultaneously by a single injection technique the day before and the day after the operation. Preoperatively V-I was correlated to V-E, and both these volumes were correlated to the plasma volume (PV). Postoperatively only the correlation between V-I and PV was found. The changes in V-I and PV were significantly correlated, but there was no correlations between the changes in V-I and V-E or between the changes in these volumes and in the body weight. Inulin seems to be a better tracer than [51Cr]EDTA, but the lack of correlation between the changes in V-I and V-E and the changes in body weight raises some doubts as to the physiological significance of the measured changes.