Technical aspects of different donor plasmapheresis systems and biological results obtained in collected plasma.

Four plasmapheresis systems were comparatively studied: a centrifugation system (Haemonetics Model 50) and three filtration ones (Dideco BT 810, Organon Teknika PLASMAPUR and HemaScience Autopheresis Plasmacell). For each separator we studied the technical conditions for plasma separation, the biological characteristics of the collected plasma and the in vitro recovery of factor VIIc after preparation of cryoprecipitates. Concerning the plasma extraction rate, the HemaScience apparatus was the most efficient but values were quite similar to those obtained with the Organon Teknika machine. Contaminating cells were only found in plasma separated with the Haemonetics. Total protein and immunoglobulin levels were higher in plasma collected with the Haemonetics and HaemaScience systems. Factor VIIIc activity was comparable in plasma separated by filtration or by centrifugation while fibrinopeptide A levels were higher in plasma collected by Haemonetics. Whatever the machine, no statistical difference was observed when in vitro recovery of factor VIII was studied.