Comparison of filtering efficiency of four new in-line blood transfusion filters

Efficient removal of debris from stored human blood prior to transfusion has become increasingly important. The debris, consisting largely of microaggregates of platelets and fibrin, is not effectively removed by passage through a standard transfusion filter. This study evaluated the performance of four of the currently available small pore in-line blood transfusion filters. Filters tested included the Bentley PF-127, the Pall Ultipor SQ-40, the Swank In-Line IL-200 and the Fenwal Microaggregate Blood Filter. A standard blood administration filter was also tested, the McGraw V-2950. The rate of blood flow through the filters was recorded using single and multiple units of blood. The screen filtration pressure and debris weight of the filtered blood were studied to compare effectiveness of filtration. The Swank filter was effective in debris removal and maintained good flow rates. The Bentley and Fenwall filters removed debris nearly as well, but had reduction of flow rates after smaller infusions. The Pall filter maintained high flow rates but did not remove debris as effectively, particularly with pressure infusion. The standard 170 mu pore blood transfusion filter does not remove microaggregates.