Physiological quality assessment of stored whole blood by means of electrical measurements.

The physiological parameters of blood such as extracellular Na(+), K(+), Cl(-), pH, 2,3-DPG and ATP and the complex electrical impedance were measured using whole blood samples from 31 male donors (21 donors form the training set and ten donors were used for testing), on the 0th, 10th and 21st day of blood bank storage. During storage, while the extracellular fluid resistance (R(e)) and the intracellular fluid resistance (R (i)) decreased progressively with time, the effective cell membrane capacitance (C(m)) has increased. Blood bank storage resulted in a rise in K(+) and a fall in Na(+), Cl(-), pH, 2,3-DPG and ATP. Accordingly, all electrical parameters correlated with Na(+), K(+), Cl(-), pH and ATP, at varying levels. By applying the multi-regression analysis, it was demonstrated that R (i), R (e) and especially C (m) were appropriate for the assessment of Na(+), K(+), Cl(-), pH and ATP until the 21st day of storage.