Background and objectives: The RCM1 leucocyte-reduction filter has been incorporated into two types of blood-donation sets of which one uses back-priming of the leucocyte filter with SAG-M solution. In this study we have compared the leucocyte-reduction efficacy of the RCM1 filter with or without back priming with SAG-M solution.
Materials and methods: This study was a retrospective analysis of quality control data of 3529 leucocyte-filtered red cell units. Of these, 1002 whole-blood units were collected in a donation set that was back-primed by letting the SAG-M solution in the final storage bag run backwards through the filter into the bag of concentrated red cells. The remaining 2527 units were collected in a donation set that required no back-priming. Postfiltration leucocyte concentration was assessed using flow cytometry.
Results: There was a significant trend towards lower leucocyte concentration in the units in which back-priming of the filter preceded filtration, as compared to units filtered without back-priming [chi2trend= 18.8, degrees of freedom (d.f.) = 1, P < 0.0005].
Conclusions: Back-priming of the RCM1 filter for red cells with SAG-M solution is superior to no back-priming with regard to leucocyte-reduction efficacy.