Background: The hydroxyethyl starch (HES) contained in University of Wisconsin (UW) solution causes erythrocyte aggregation. The effect of UW on red blood cell (RBC) deformability is still unclear. HES-free preservation solutions, Celsior (CS) and Custodiol (CU) are available. In this study we evaluated whether they really showed a reduced aggregating and stiffening effect on RBCs when compared with UW. We was also evaluated the effect of these solutions on cellular membranes by measuring acetylcholinesterase (AChE), which is a marker of RBC membrane integrity.
Methods: The determination of RBC aggregation and deformability was performed by a laser-assisted optical rotation cell analyzer (LORCA). AChE measurement was performed with a spectrophotometric technique.
Results: The mean RBC aggregation index (AI) measured in pure blood control samples was 28.00 +/- 0.73%. The AI measured samples containing UW was 38.82 +/- 1.58%. In samples with CS, it was 13.307 +/- 0.64% and in samples with CU the mean AI was 12.47 +/- 0.42%. Also the RBC aggregating time was quicker in presence of UW compared with controls. AChE concentration in blood was 3.043 +/- 0.4 nmol. CS and UW did not produce any significant change; a significant reduction was found when CU was added to blood, namely 1.975 +/- 0.1 nmol (P < .05). The use of UW or CS or CU did not result in any significant change in RBC deformability.
Discussion: CS and CU solutions do not aggregate erythrocytes, whereas Wisconsin does massively. CU causes an alteration of RBC cellular membrane as demonstrated by depletion of AChE.