title: Storage of thawed plasma for a liquid plasma bank: impact of temperature and methylene blue pathogen inactivation.
abstract: BACKGROUND
  Rapid transfusion of fresh-frozen plasma (FFP) is desired for treating coagulopathies, but thawing and issuing of FFP takes more than 40 minutes. Liquid storage of plasma is a potential solution but uncertainties exist regarding clotting factor stability. We assessed different storage conditions of thawed FFP and plasma treated by methylene blue plus light (MB/light) for pathogen inactivation.
  
  
  METHODS
  Fifty thawed apheresis plasma samples (approx. 750 mL) were divided into three subunits and either stored for 7 days at 4°C, at room temperature (RT), and at 4°C after MB/light treatment. Clotting factor activities (Factor [F] II, FV, FVII through FXIII, fibrinogen, antithrombin, von Willebrand factor antigen, Protein C and S) were assessed after thawing and on Days 3, 5, and 7. Changes were classified as "minor" (activities within the reference range) and "major" (activities outside the reference range).
  
  
  RESULTS
  FFP storage at 4°C revealed major changes for FVIII (median [range], 56% [33%-114%]) and Protein S (51% [20%-88%]). Changes were more pronounced when plasma was stored at RT (FVIII, 59% [37%-123%]; FVII, 69% [42%-125%]; Protein S, 20% [10%-35%]). MB/light treatment of thawed FFP resulted in minor changes. However, further storage for 7 days at 4°C revealed major decreases for FVIII (47% [12%-91%]) and Protein S (49% [18%-95%]) and increases for FVII (150% [48%-285%]) and FX (126% [62%-206%]).
  
  
  CONCLUSIONS
  Storage of liquid plasma at 4°C for 7 days is feasible for FFP as is MB/light treatment of thawed plasma. In contrast, storage of thawed plasma for 7 days at RT or after MB/light treatment at 4°C affects clotting factor stability substantially and is not recommended.
authors: Institut für Immunologie und Transfusionsmedizin, Ernst-Moritz-Arndt Universität, Greifswald, Germany.
authors: Thomas
authors: T
authors: Thiele
authors: Sarah
authors: S
authors: Kellner
authors: Gregor
authors: G
authors: Hron
authors: Christina
authors: C
authors: Wasner
authors: Matthias
authors: M
authors: Nauck
authors: Kathrin
authors: K
authors: Zimmermann
authors: Antje
authors: A
authors: Wessel
authors: Theodore E
authors: TE
authors: Warkentin
authors: Andreas
authors: A
authors: Greinacher
authors: Kathleen
authors: K
authors: Selleng
mesh_terms: D000094902:Blood Banking / Q000379:methods*; D001777:Blood Coagulation / Q000187:drug effects / Q000528:radiation effects; D001781:Blood Component Removal / Q000379:methods; D001793:Blood Preservation / Q000379:methods*; D017848:Blood-Borne Pathogens / Q000187:drug effects* / Q000528:radiation effects; D003080:Cold Temperature; D015925:Cryopreservation / Q000379:methods; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D008027:Light; D008751:Methylene Blue / Q000494:pharmacology*; D010949:Plasma / Q000187:drug effects* / Q000528:radiation effects
chemical_list: D004791:Enzyme Inhibitors; D008751:Methylene Blue