title: Thawing procedures and the time course of clotting factor activity in fresh-frozen plasma: a controlled laboratory investigation.
abstract: BACKGROUND
  In this study, we evaluated the effects of the thawing process of 2 commercially available devices on the activity of clotting factors, inhibitors and activation markers of the hemostatic system in fresh-frozen plasma (FFP). In an experimental procedure, FFP was thawed under running warm water at 42 degrees C.
  
  
  METHODS
  Plasma of 20 healthy donors was sampled, separated, and distributed in 3 plasma bags. Within 2 h after sampling plasma bags was frozen at a temperature of -30 degrees C to -40 degrees C and stored for at least 8 wk. After sampling (baseline) as well as immediately and 1, 2, 4, and 6 h after thawing, the activity of FV, FVII, FVIII, fibrinogen, fibrin monomers (FM), d-dimers (DD), alpha2-antiplasmin (alpha2-AP), and protein S (PS) was determined from each plasma bag.
  
  
  RESULTS
  From 1 h to 6 h after thawing, no significant differences in the activity of the investigated coagulation markers dependent on the thawing procedure were found. However, immediately after thawing and independent of the thawing procedure, the activity of FVII was significantly decreased (P < 0.01), whereas FM were significantly increased (P = 0.001).
  
  
  CONCLUSIONS
  The thawing procedures studied exhibited no significant influence on activity and stability of the investigated markers of coagulation over the study period. The decreased activity of FVII and the clinical significance of the increase in FM require further research.
authors.affiliation: Department of Anesthesiology and Intensive Care Medicine, Charité-University Hospital Berlin, Charité Campus Mitte, Berlin, Germany. christian.von_heymann@charite.de
authors.forename: Christian
authors.initials: C
authors.lastname: von Heymann
authors.forename: Axel
authors.initials: A
authors.lastname: Pruss
authors.forename: Michael
authors.initials: M
authors.lastname: Sander
authors.forename: Anne
authors.initials: A
authors.lastname: Finkeldey
authors.forename: Sabine
authors.initials: S
authors.lastname: Ziemer
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kalus
authors.forename: Holger
authors.initials: H
authors.lastname: Kiesewetter
authors.forename: Abdulgabar
authors.initials: A
authors.lastname: Salama
authors.forename: Claudia
authors.initials: C
authors.lastname: Spies
mesh_terms: D000328:Adult; D001777:Blood Coagulation / Q000502:physiology*; D001779:Blood Coagulation Factors / Q000502:physiology*; D001793:Blood Preservation / Q000379:methods*; D015925:Cryopreservation / Q000379:methods*; D005260:Female; D006361:Heating / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D010949:Plasma
chemical_list: D001779:Blood Coagulation Factors