title: In vitro evaluation of prestorage pooled leukoreduced whole blood-derived platelets stored for up to 7 days.
abstract: BACKGROUND
  Advantages to storing whole blood-derived platelets (PLTs) as a pool for 7 days would include operational efficiencies and facilitation of bacterial testing and pathogen inactivation. The in vitro quality of pre-storage pooled PLTs stored for up to 7 days was assessed.
  
  
  METHODS
  Leukoreduced PLTs were pooled before storage (5 units/pool) and stored for either 5 or 7 days. Samples were collected at the time of pooling and either on Day 5 (n=16-29) or on Day 7 (n=4-30) and tested for biochemical and activation markers and morphology and/or shape change. Control PLTs were stored individually for 5 or 7 days and then tested as indicated above.
  
  
  RESULTS
  The mean PLT counts (x10(9)/L) were similar: control PLTs, 1344 (464 SD); and prestorage pooled PLTs, 1327 (220 SD; p=0.93). On Day 5, the pH value was significantly lower (p<or=0.0001) for the prestorage pooled PLTs. Lactate and partial pressure of O2 (pO2) were significantly higher (p<or=0.003). On Day 7 of storage, significant differences were noted with pH, pCO2, and hypotonic shock all being lower with the prestorage pooled product, whereas pO2, lactate, and morphology scores were higher (p values all <0.03). Although significant differences were found, the magnitude of the difference would not be expected to impact on transfusion outcomes.
  
  
  CONCLUSIONS
  These results suggest that prestorage pooled PLTs can be stored for up to 7 days; however, studies are needed to ensure that the clinical benefit of PLTs stored as a pool is not inferior to those stored individually.
authors.affiliation: Department of Medicine, McMaster University, Canadian Blood Services, Hamilton, Ontario, Canada. heddlen@mcmaster.ca
authors.forename: N M
authors.initials: NM
authors.lastname: Heddle
authors.forename: R L
authors.initials: RL
authors.lastname: Barty
authors.forename: C S
authors.initials: CS
authors.lastname: Sigouin
authors.forename: D M
authors.initials: DM
authors.lastname: Boye
authors.forename: E J
authors.initials: EJ
authors.lastname: Nelson
authors.forename: M A
authors.initials: MA
authors.lastname: Blajchman
authors.forename: J G
authors.initials: JG
authors.lastname: Kelton
mesh_terms: D015415:Biomarkers / Q000097:blood; D001781:Blood Component Removal; D001792:Blood Platelets / Q000378:metabolism*; D001793:Blood Preservation; D048430:Cell Shape; D005069:Evaluation Studies as Topic; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D007958:Leukocyte Count; D007962:Leukocytes; D007959:Lymphocyte Culture Test, Mixed; D009997:Osmotic Pressure; D010100:Oxygen / Q000032:analysis; D019007:P-Selectin / Q000097:blood; D015539:Platelet Activation; D010976:Platelet Count; D010983:Plateletpheresis; D013997:Time Factors
chemical_list: D015415:Biomarkers; D019007:P-Selectin; D007770:L-Lactate Dehydrogenase; D010100:Oxygen