The role of bicarbonate in platelet additive solution for apheresis platelet concentrates stored with low residual plasma.
BACKGROUND
Complex platelet additive solutions (PASs) are required to store platelet (PLT) concentrates with plasma levels below 30%. Previously, apheresis PLTs stored with 5% plasma in acetate- and bicarbonate-containing PAS maintained stable pH and bicarbonate levels during 7-day storage. Due to this observation, the necessity of added bicarbonate in PAS was investigated and whether the concurrent increase in PAS pH after bicarbonate addition had any effect on PLT storage.


METHODS
Apheresis PLTs were stored in 5% plasma-95% high- or low-pH PAS, with or without bicarbonate (n=10 per arm). Bicarbonate PAS PLTs were paired and nonbicarbonate PAS PLTs were paired (split from same double-dose collection). PLTs were evaluated for in vitro variables on Days 1 and 7 and up to Day 14 if the Day 7 pH was higher than 6.2.


RESULTS
PLT pH was maintained above 7.3 to Day 14 in bicarbonate PAS PLTs while pH failures below 6.2 were observed in 4 of 10 and 2 of 10 units on Day 7 in low- and high-pH nonbicarbonate PAS arms, respectively. Day 7 in vitro variables in nonbicarbonate PAS PLTs with pH values of higher than 6.2 were comparable to Day 7 variables in bicarbonate PAS PLTs. The pH of bicarbonate PAS did have a small effect on pH and bicarbonate levels in PLT units, but did not have an effect on functional variables and metabolism.


CONCLUSIONS
Bicarbonate was not required to maintain in vitro PLT function in 5% plasma-95% PAS, but was required as a pH buffer and increased PAS pH did not significantly contribute to this effect.
Fenwal, Inc., Lake Zurich, Illinois 60047, USA.
Katherine
K
Radwanski
Kyungyoon
K
Min
D001639:Bicarbonates / Q000494:pharmacology*; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D001793:Blood Preservation / Q000379:methods*; D048430:Cell Shape / Q000187:drug effects; D005947:Glucose / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D010949:Plasma / Q000502:physiology*; D010983:Plateletpheresis; D011310:Preservatives, Pharmaceutical / Q000494:pharmacology; D012996:Solutions / Q000494:pharmacology; D013696:Temperature
D001639:Bicarbonates; D011310:Preservatives, Pharmaceutical; D012996:Solutions; D005947:Glucose