Filtration characteristics of polyester mesh (Pall) micropore blood transfusion filter

Stored human blood of varying age was passed through polyester mesh (Pall) micropore blood transfusion (pore size, 40 mu). Passage through the filter resulted in decreased screen filtration pressure (SFP) of the blood and increased filter weight. Mumerous microaggregates were removed, but SFP did not return to normal after filtration. On the basis of this research, we conclude that polyester mesh micropore blood transfusion filters are not as effective as Dacron wool (Swank) transfusion filters in removal of micro-aggregates from stored human blood. If a polyester mesh filter must be used, it is recommended that once occlusion of the filter has occurred, the filter should then be discarded and another inserted.