Improvement of separation efficiency and concentrate purity of the Fresenius cell separator AS 104: results of a multicenter study. Haemapheresis Scientific Workshop Group of DGTI.
The aim of this multicenter study, initiated by the Haemapheresis Scientific Workshop Group of the DGTI was to evaluate separation protocols for the cell separator AS 104, marketed by Fresenius, using modified software and parameters which were believed to allow a more effective platelet collection with a significantly lower leukocyte contamination of the concentrates.  Plateletpheresis data from 950 runs in ten hemapheresis centers, using virtually the same equipment, identical pheresis protocols, and cell counting methods were registered and statistically analyzed for each center and machine-related differences.  Additionally, the counting methods of the centers were controlled by bi-weekly external cell count trials, and the plateletpheresis data were corrected using the results of these cell count trials, to obtain a comparison of the two versions of the protocol independent of the center effect.  For protocol (or software version) 4.1, 610 runs were registered.  The results of cell countings (chamber) are (given as means+/-standard deviations) 3.452x10 11+/-1.009x10 11 for the platelet yield (or thrombocyte yield), 9x10 6+/-23x10 8 for leukocyte contamination, and 17x10 6+/-70x10 6 for the erythrocyte contamination, and 53%+/-13.5% for the extraction efficiency, respectively.  For software version 4.4 with 340 runs, the results are 3.642x10 11+/-0.974x10 11 for the platelet yield, 15x10 6+/-74x10 8 for leukocyte contamination, 20x10 6+/-44x10 6 for erythrocyte contamination, and 59%+/-12.4% for the extraction efficiency, respectively.  For the leukocyte and erythrocyte contaminations, the means and standard deviations must be interpreted carefully since the statistical distribution showed a considerable skewing of the data.  From the automatic counts, marginally smaller means were found.  The data were corrected by the values from the ring study; and for these mathematically corrected data, statistical tests showed a significant improvement in the extraction efficiency from software version 4.1 to 4.4.  At the same time, the leukocyte contamination was significantly lower with version 4.4.
Müller
N
N
Institut für Transfusionsmedizin der Universität, Gesamthochschule-Essen, Germany.
Kretschmer
V
V
Godehardt
E
E
Borberg
H
H
Neumann
H J
HJ
D001781:Blood Component Removal / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data; D002469:Cell Separation / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D005069:Evaluation Studies as Topic; D006801:Humans; D010976:Platelet Count / Q000295:instrumentation / Q000379:methods; D010983:Plateletpheresis / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D012984:Software