The evolving role of lyophilized plasma in remote damage control resuscitation in the French Armed Forces Health Service.

Freeze-dried plasma was developed by the US Army for the resuscitation of combat casualties during World War II. The French Military Blood Institute began producing French lyophilized plasma (FLYP) in 1949, in accordance with French blood product guidelines. Since 2010, a photochemical pathogen inactivation process has been implemented to reduce the remaining transfusion-related infectious risk. All quality controls for this procedure verify that the hemostatic properties of FLYP are conserved. FLYP is compatible with all blood types, can be stored at room temperature for 2 years, and its reconstitution requires less than 6 minutes. As a result, FLYP allows quick delivery of all the coagulation proteins and the application of a 1:1 ratio of FLYP and red blood cells in the context of a massive transfusion. Hemovigilance data collected in France since 1994 have included FLYP. Results indicate no reporting of infection related to the use of FLYP. Clinical monitoring with a focus on hemostasis was implemented in 2002 and expanded in 2010. The data, obtained from overseas operations, confirmed the indications, the safety and the clinical efficacy of FLYP. Further research is needed to determine specific indications for FLYP in the therapeutic management of civilian patients with severe hemorrhage.

In vitro hemostatic properties of French lyophilized plasma.

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.