T. Zeiler et al., Periodic alternating interface positioning to lower WBC contamination of apheresis platelet concentrates: a multicenter evaluation, TRANSFUSION, 40(6), 2000, pp. 687-692
BACKGROUND: A new software version of a cell separator (AS TEC 204, Freseni
us) providing WBC-reduced single-donor plateletpheresis concentrates was te
sted.
STUDY DESIGN AND METHODS: Dual-needle apheresis procedures (n = 621) were p
erformed in three centers, using either fixed interface positioning (FIP) o
r periodic alternating interface positioning (PAIP). The other separation p
arameters (e.g., anticoagulant: whole-blood ratio, and blood flow) were set
individually. All platelet concentrates were evaluated for platelet yields
and contaminating WBCs.
RESULTS: The introduction of the PAIP resulted in a significant (p < 0.001)
reduction in contaminating WBCs (median, 30,000) from the numbers seen wit
h FIP (median, 2,300,000) while maintaining the separation efficacy (47%) a
nd separation time. Ninety-eight percent of all concentrates contained less
than 5 x 10(6) WBCs per concentrate and 92 percent contained less than 1 x
10(6).
CONCLUSION: Plateletpheresis using the AS TEC 204 cell separator with PAIP
is a valid alternative to WBC reduction by filtration. It may provide WBC-r
educed platelet concentrates without the additional cost of filters. Howeve
r, the reliability of the WBC reduction is not yet advanced enough that PAI
P can be employed without any monitoring of the end product.