平膜積層膜モジュールによる落差式プラズマフェレーシスシステムの開発

Abstract

We have developed a new plasmapheresis system to separate plasma using gravity, without electrical pumps. This system consists of two bags to collect whole blood and plasma, one needle and a disk type plasma separator (13 layers of flat polypropylene membranes; thickness 120μm, poresize 0.6μm, effective surface area 0.13m2). After the collection of whole blood with anticoagulant in one bag, this whole blood bag is hung on the top of the irrigator and the blood is run through the separator using only gravity. The spontaneously separated plasma was collected into the plasma collection bag. The red cells, intended for return to the donor in the donor plasmapheresis system, were collected in the other bag for in vitro study. An average of 183.7ml of plasma was collected from 448ml of whole blood within 11 minutes without any hemolysis. The separated plasma contained no cellular components. Though the collected plasma was diluted by the saline used to wet the filter, the sieving coefficients of most of plasma components were higher than 0.95. There were no significant increases of anaphylatoxins (C3a, C4a, C5a). In the red cell concentrates, the recovery of red cells, white cells and platelets was 91.4%, 93.8% and 61.9%, respectively. Neither osmotic fragility of red cells nor platelet functions had changed. These observations suggest that this new pumpless plasma separator is useful as a simple, economical and safe donor plasmapheresis system.