THE RATE OF ATTAINMENT OF DIFFUSION EQUILIBRIUM FOR THIOCYANATE BETWEEN PLASMA AND TRANSUDATES FOL- LOWING THE INTRAVENOUS INJECTION OF SODIUM THIOCYANATE IN PATIENTS WITH EDEMA

Estimations of the volume of extracellular fluid in man have been made by calculating the volume of body fluid through which thiocyanate is dis-tributed after the intravenous administration of sodium thiocyanate (1, 2, 3). In the method as proposed, a known amount of sodium thiocyanate in solution is administered intravenously and blood is drawn for the measurement of the con-centration of thiocyanate in the serum 1 or 2 hours after the injection (1, 2). It has been demonstrated in normal man that the distribution of thiocyanate is rapid and that diffusion equi-librium is attained within 1 hour after injection (1, 2, 3). The time required for the attainment of equi