WBC-reduced platelet concentrates from pooled buffy coats in additive solution: an evaluation of in vitro and in vivo measures.
BACKGROUND
The use of a platelet additive solution (PAS-II, Baxter) may have benefits over plasma for storage of platelets. It was the aim of this study to develop a method to produce WBC-reduced platelet concentrates (PCs) in PAS-II with >240 x 10(9) platelets and <1 x 10(6) WBCs per unit, which can be stored for 5 days at pH >6.8 and that will give sufficient platelet increments after transfusion: a 1-hour CCI of >7.5 and a 20-hour CCI of >2.5.


METHODS
PCs were made from five pooled buffy coats and 250 g of PAS-II. After centrifugation the PCs were WBC-reduced with a filter (Autostop BC, Pall Biomedical) and stored in a 1000-mL polyolefin container. CCIs were assessed in stable hemato-oncologic patients after 5-day old PCs were transfused.


RESULTS
Routinely produced PCs contained a median of 310 x 10(9) platelets (n = 5,363) with 3.5 percent containing <240 x 10(9) platelets, in a median volume of 320 mL (n = 11,834). The median number of WBCs was <0.03 x 10(6) (n = 694). The WBC count exceeded 1 x 10(6) in three PCs, but it was always <5 x 10(6), giving 99-percent confidence that more than 99.5 percent of the units will contain <1 x 10(6) WBCs. The pH remained >6.8 on Day 8, provided the concentration was below 1.1 x 10(9) platelets per mL (n = 32). After 28 transfusions in 28 patients, the 1-hour CCI was 12.6 +/- 4.3 (mean +/- SD, with 2/28 CCIs <7.5) and the 20-hour CCI was 8.9 +/- 5.6 (with 4/28 CCIs <2.5). Limitations of this study include the absence of a control group of patients receiving platelets stored in plasma and of in vivo radiolabeled survival studies, but a comparison of these data with previously published data suggested that the in vivo survival of platelets stored in PAS-II is less than that of platelets stored in plasma.


CONCLUSIONS
The WBC-reduced PCs conformed to specifications. These WBC-reduced PCs could be stored at least 5 days with maintenance of pH, and they gave sufficient increments after transfusion to patients.
van der Meer
P F
PF
Blood Bank of North Holland, Plesmanlaan 125, Postbus 9137, 1006 AC Amsterdam, the Netherlands. bnhams@hetnet.nl
Pietersz
R N
RN
Tiekstra
M J
MJ
Huijgens
P C
PC
Dekker
W J
WJ
Reesink
H W
HW
D000225:Adenine / Q000494:pharmacology*; D001792:Blood Platelets; D001793:Blood Preservation; D005947:Glucose / Q000494:pharmacology*; D006801:Humans; D007962:Leukocytes / Q000166:cytology*; D008353:Mannitol / Q000494:pharmacology*; D012965:Sodium Chloride / Q000494:pharmacology*
C037839:ADSOL; D008353:Mannitol; D012965:Sodium Chloride; D005947:Glucose; D000225:Adenine