The hematocrit-electrolyte-concentration-apparatus (HECA).

: An instrument was developed which can simultaneously determine the hematocrit and the total electrolyte concentration in blood and plasma respectively. It is possible to correct the hematocrit value for fluctuations of the total electrolyte concentration. Pilot studies of this device have been conducted on physiological and rigid erythrocyte suspensions and on plasma with various total electrolyte concentration. In the future, this device will be employed in analyzing blood and plasma of patients undergoing hemodialysis.