Evaluation of a new, integral, whole blood filter (RS2000) system for prestorage leucodepletion of SAG-M red cells

Residual donor leucocytes are responsible for many adverse transfusion reactions, Prestorage leucodepletion may ameliorate these effects and enhance product quality, We studied a bottom and top (BAT) system incorporating an integral filter for whole blood leucodepletion. Our evaluation assessed leucodepletion efficiency as well as in vitro SAG-M red cell quality and storage characteristics. Sixty-six units of blood were collected; test units into the Optipac(R)-pLuS system and controls into the standard triple pack configuration, Test units were held for 4-6 h at room temperature (rt) or 12-18 h at 4 degrees C, The mean leucocyte counts for the SAG-M red cells in the quality and storage trial were 0 . 6, x 10(6) (rt hold), 0 . 05 x 10(6) (4 degrees C hold) and 2500 x 10(6) (controls). We observed no significant differences between the groups for Na+, ATP, 2,3-DPG, glucose, lactate and pH during the 49 d storage. The control group, however. showed a greater increase in haemolysis and K+ with time. Autologous in vivo 24 h red cell recovery, after 42 d storage, was > 75%. Adjustment of processing parameters in subsequent studies gave leucodepleted SAG-M red cells with minimal cell loss (9-19%) plus acceptable haemoglobin content (46-76 g/U) and haematocrit (54-62%). This system achieved > 3 . 5 log leucodepletion with all but one unit containing < 1 x 10(6) leucocytes. The product quality is good and the system suitable for routine use in blood centres.