Clinical performance of a high-efficiency rapid flow leucocyte removal filter for leucocyte depletion of heparinized cardiopulmonary bypass perfusate.

The method of leucocyte depletion has been recently introduced to the field of cardiopulmonary bypass to reduce leucocyte-mediated organ dysfunction. In this study, we evaluated the efficacy and biocompatibility of the Pall RC400 filters for leucocyte depletion of heparinized cardiopulmonary bypass (CPB) perfusate taken from the heart-lung machine during routine cardiac surgery. For each filter, 700 ml blood were used as filtrate. Filtration was divided into the following groups to study the effect of loading pressure on the efficacy of the filters: under gravity pressure as a control (n = 8), under 100 mmHg (n = 8), 200 mmHg (n = 8), and 300 mmHg loading pressure (n = 8) driven by a roller pump. In addition, heparinized predonation blood taken at the beginning of CPB (n = 8) was filtered under gravity in comparison with the perfusate taken at the end of CPB. The results showed that the average leucocyte removal rate by an RC400 filter for 700 ml of blood was 96.8%. There was no significant difference of leucocyte removal rate between filtration under gravity and under loading pressure up to 300 mmHg. This allows clinical filtration at a speed up to 500 ml/min. The platelet removal rate was significantly higher in blood taken at the beginning of CPB than in blood taken at the end of CPB. Complment split product, C5a, increased only slightly during filtration indicating that this filter, made from polyester, has a good blood compatible characteristic. We conclude that the Pall RC400 leucocyte removal filter is suitable and safe to be used for leucocyte filtration of heparinized CPB perfusate during cardiac surgery.