title: In vitro hemostatic properties of French lyophilized plasma.
abstract: BACKGROUND
  French lyophilized plasma (FLyP) is used routinely by the French Armed Forces in war settings. The authors compared concentrations of coagulation proteins and global in vitro hemostatic properties in FLyP and in the same plasma before lyophilization to assess the impact of lyophilization on coagulation properties.
  
  
  METHODS
  Twenty-four batches of plasma before and after lyophilization were tested for coagulation proteins. Thrombin generation time, thrombin antithrombin concentration, prothrombin fragment 1 + 2, and thromboelastography were assessed. Finally, the efficiencies of FLyP and plasma before lyophilization were compared on a hemorrhagic shock hemodilution model and tested on TEG(Haemoscope Corporation, Glenview, IL).
  
  
  RESULTS
  Prothrombin time ratio (1.1 ± 0.1 vs. 1.2 ± 0.1) and activated partial thromboplastin time (35 ± 1.3 vs. 39 ± 2.4 s) were significantly increased in FLyP (8 ± 3%, P < 0.05 and 11 ± 5%, P < 0.001, respectively). Activity of factors V (85 ± 18 vs. 51 ± 16 UI/ml) and VIII (0.77 ± 0.11 vs. 0.62 ± 0.10 UI/ml) was also diminished (25 ± 12% and 20 ± 7%, respectively); however, activity of other factors was preserved. The authors observed no alteration in the thromboelastographic parameters. Thrombin generation was preserved when induced with 5 pM tissue factor in vitro but significantly reduced when using 1 pM tissue factor. The thrombin-antithrombin complex and prothrombin fragment 1 + 2 attested for the absence of coagulation activation. This hemodilution model showed no significant difference before and after lyophilization.
  
  
  CONCLUSIONS
  The study results account for a significant decrease of factors V and VIII in FLyP. However, the global capacity to induce clot formation in vitro seems to be preserved. The clinical relevance of these decreased factors is not known.
authors: Fédération de Biologie Clinique, Clamart, France. christophe.martinaud@inserm.fr
authors: Christophe
authors: C
authors: Martinaud
authors: Corinne
authors: C
authors: Civadier
authors: Sylvain
authors: S
authors: Ausset
authors: Catherine
authors: C
authors: Verret
authors: Anne-Virginie
authors: AV
authors: Deshayes
authors: Anne
authors: A
authors: Sailliol
mesh_terms: D001777:Blood Coagulation; D001780:Blood Coagulation Tests / Q000379:methods / Q000706:statistics & numerical data; D005165:Factor V / Q000378:metabolism; D005169:Factor VIII / Q000378:metabolism; D005260:Female; D005602:France; D005612:Freeze Drying; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D010446:Peptide Fragments / Q000378:metabolism; D010949:Plasma / Q000378:metabolism*; D011516:Prothrombin / Q000378:metabolism; D013916:Thrombelastography / Q000379:methods / Q000706:statistics & numerical data; D013917:Thrombin / Q000378:metabolism; D013925:Thromboplastin / Q000378:metabolism
chemical_list: D010446:Peptide Fragments; C045879:prothrombin fragment 1.2; D005165:Factor V; D011516:Prothrombin; D005169:Factor VIII; D013925:Thromboplastin; D013917:Thrombin