Academic literature on the topic '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.

SummaryRecombiplastin, a recombinant a human tissue factor, elaborated by Ortho Diagnostic Systems, produced by Baculovirus and relipidated with highly purified phospholipids, was tested as a new reagent for determining prothrombin time (PT) in a French multicentric study. Its intralaboratory- performances, including sensitivity, repeatability, reproducibility and stability, were explored to establish whether its use would reduce the interlaboratory dispersion of PT values, and therefore improve the standardization of oral anticoagulant treatment.The 9 university hospital hematology laboratories involved in this study used the same type of instrument (KC 10). For 10 consecutive days, they determined PTS on a normal plasma pool, plasma dilutions of 1/2, 1/3 and 1/8, 3 identical lyophilized calibrated plasmas, as well as plasmas from 20 normal subjects, 50 patients on oral anticoagulant therapy with Recombiplastin which has an International Sensitivity Index (ISI) of 1, and 2 commercial thromboplastin extracts (ISI #1 or 2). In the patients on anticoagulants, factors VII, X and V were measured when results were conflicting.The intra and interlaboratory reproducibilities of Recombiplastin, calculated on the basis of either PTS expressed in seconds, or of the International Normalized Ratio (INR), were good, with coefficients of variation (CV) similar to those observed with the 5 other reagents used by the different laboratories (2% <CV <8%).The stability of Recombiplastin was excellent, with no variation in PT after 72 h of incubation at 37° C.A normal PT of 12 s was obtained with Recombiplastin, similar to the values found for the reagents with ISI #2. In the patients on anticoagulants, Recombiplastin gave the longest coagulation times (PTRecombipiastin = 64.2 s vs PTNeoPlastin = 32.8 s, and PTThromborel = 54.4 s). These results suggest that Recombiplastin is highly sensitive to the changes in coagulation induced by anticoagulants. Recombiplastin was more sensitive to factor VII deficiency than any of the other reagents, even those with ISI #1.The coefficients of correlation between the INRS calculated on the basis of the PTS obtained with Recombiplastin and the INRS based on the PTS for other thromboplastins, were satisfactory (0.85 <R <0.95) but a breakpoint in the slope of the regression curves was observed when INR >4. This observation requires further investigation, particularly in connection with the exact ISI values for Recombiplastin and the other thromboplastins used in this study.In conclusion, Recombiplastin is stable and sensitive and gives accurate reproducible results. However, the behavior of Recombiplastin is slightly different from that of the commercial reagents whether their ISI is 1 or 2, and its use did not reduce the interlaboratory dispersion of PT values.

BackgroundHaemorrhagic shock remains the leading cause of preventable death in overseas and austere settings. Transfusion of blood components is critical in the management of this kind of injury. For French naval and ground military units, this supply often takes too long considering the short shelf-life of red blood cell concentrates (RBCs) and the limited duration of transport in cooling containers (five to six days). Air-drop supply could be an alternative to overcome these difficulties on the condition that air-drop does not cause damage to blood units.MethodsAfter a period of study and technical development of packaging, four air-drops at medium and high altitudes were performed with an aircraft of the French Air Force. After this, one air-drop was carried out at medium altitude with 10 RBCs and 10 French lyophilised plasma (FLYP). A second air-drop was performed with a soldier carrying one FLYP unit at 12 000 feet. For these air-drops real blood products were used, and quality control testing and temperature monitoring were performed.ResultsThe temperatures inside the containers were within the normal ranges. Visual inspection indicated that transfusion packaging and dumped products did not undergo deterioration. The quality control data on RBCs and FLYP, including haemostasis, suggested no difference before and after air-drop.DiscussionThe operational implementation of the air-drop of blood products seems to be one of the solutions for the supply of blood products in military austere settings or far forward on battlefield, allowing safe and early transfusion.

SummaryFor laboratory control of oral anticoagulation, amidolytic factor X (F X) determination may offer an alternative to standardization difficulties of prothrombin time (PT). In order to validate this amidolytic assay on a large scale, a multicenter study was undertaken in 6 French laboratories using the same chromogenic substrate (Stachrom X Stago) and different automated instruments. Intra and between laboratory reproducibility of factor X was estimated on fresh and lyophilized patients plasmas and was found to be highly satisfactory. Standardization of the method did not seem to depend on the chromogenic substrate used, as investigated in two different centers. Results of PT and factor X were compared in over 500 patients on a longterm stabilized oral anticoagulant treatment: there was a strong positive correlation between the 2 tests in each center. The therapeutic range for factor X was evaluated from therapeutic PT values reported by Duckert and Marbet for the different thromboplastin reagents: the estimated mean range was 21 to 32%.Pooling the results of the six different centers a concordant information for prothrombin time and factor X amidolytic assay was found in 76% of patients and a fully discordant response was present in 0.6%. The results suggest that amidolytic factor X may be suitable for monitoring long-term anticoagulation. However, prospective trials are needed to evaluate its usefulness as compared to conventional methods.

IntroductionSince 2013, the French Army Health Service, in agreement with international experts, has recommended the administration of 1 g of tranexamic acid (TXA) in trauma patients in haemorrhagic shock or at risk of bleeding within 3 hours of the trauma.MethodsThe aim of this analysis was to describe the administration of TXA in French military personnel wounded during military operations in the Sahelo-Sahelian band between October 2016 and September 2020. Data were collected from forward health records and hospital data from the French hospital where the casualty was finally evacuated. Underuse of TXA was defined as the lack of administration in casualties who had received a blood transfusion with one or more of red blood cells, low-titre whole blood or French lyophilised plasma within the first 24 hours of injury and overuse as its administration in the non-transfused casualty.ResultsOf the 76 patients included, 75 were men with an average age of 28 years. Five patients died during their management. 19 patients received TXA (25%) and 16 patients were transfused (21%). Underuse of TXA occurred in 3 of the 16 patients (18.8%) transfused. Overuse occurred in 6 of 60 (10%) non-transfused patients.ConclusionThe analysis found an important underuse of TXA (almost 20%) and highlighted the need for optimising the prehospital clinical practice guidelines to aid prehospital medical practitioners more accurately in administering TXA to casualties that will require blood products.

Le blessé de guerre est un blessé grave qui associe choc hémorragique et polytraumatisme. Malgré les progrès thérapeutiques des dernières années, l'hémorragie reste la première cause de décès évitable chez ce type de blessés. Les patients qui survivent aux premières heures de leurs blessures voient leur pronostic vital et fonctionnel menacé par les complications secondaires. Les protocoles de prise en charge des blessés de guerre basés sur le principe de damage control ressuscitation et la transfusion massive de sang total ont permis de réduire considérablement les décès par choc hémorragique. Toutefois, les contraintes logistiques des théâtres d'opérations extérieures et les afflux massifs de blessés ne permettent pas d'administrer du sang total à tous, en tout lieu. Le développement de produits sanguins labiles modifiés qui répondent aux contraintes opérationnelles pourrait améliorer la survie des blessés. Pour répondre à cet objectif, nous avons développé deux formulations de plasma lyophilisé hyperconcentré porcin, l'une sans (PLYO-H) et l'autre avec lyophilisat plaquettaire (PLYO-H/LP). Les produits obtenus présentaient des critères de qualité de production optimaux. Le PLYO-H et le PLYO-H/LP étaient riches en protéines, dont l'albumine, et présentent une hyperosmolarité à deux fois celle du plasma. Dans le PLYO-H/LP, les plaquettes lysées au cours du processus de fabrication ont libéré dans le plasma des facteurs de coagulation, dont le fibrinogène, en quantité importante. L'intérêt thérapeutique des PLYO-H et PLYO-H/LP a été évalué à l'aide d'un modèle porcin représentatif du blessé de guerre. La comparaison entre les animaux traités par PLYO, PLYO-H, PLYO-H/LP ou sang total n'a pas montré de supériorité d'un groupe par rapport aux autres. Toutefois, l'analyse des paramètres de la fonction cardiovasculaire et de l'hémostase a révélé des effets bénéfiques du PLYO-H et du PLYO- H/LP qui ouvrent la porte à des études complémentaires portant cette fois sur des formulations issues de plasmaphérèse humaine
War casualties associate multiple injuries with shock hemorrhage. Despite the therapeutic progress of recent years, hemorrhage is the leading cause of preventable deaths and secondary multiple organ failure can lead to vital and functional prognosis. Management of war-injured patients based on damage control resuscitation and massive transfusion of whole blood reduced considerably the number of deaths. Nevertheless, during foreign operations whole blood is sometimes lacking because of logistic limitations and massive casualties. Modified blood products that are free from constraints could help war-injured patients to survive. To achieve this objective, we developed two French hyper-concentrated lyophilized plasmas with (FLYP-H/LP) or not (FLYP-H) lyophilized platelets. The production of these products is of a high quality. FLYP-H and FLYP-H/LP are high protein products, especially albumin, which confer them a hyperosmolarity twice that of plasma. In FLYP-H/LP, platelets were lysed during the manufacturing process and liberated high quantities of coagulation factors, such as fibrinogen. The therapeutic effects of FLYP-H and FLYP-H/LP were evaluated thanks to our war-injured porcin model. Statistical analysis highlighted the beneficial effects of FLYP-H and FLYP-H/LP on cardiovascular function and hemostasis. These results open the door to more analysis but on human FLYP-H and FLYP-H/LP

One of the aim of the survey conducted in last december 1986 was to assess the efficacy of 2 procedures of standardization :1) the INR system, derived from thromboplastin calibration and adopted in 1983 by the WHO.2) the Reference Calibrated Plasmas (RCP) procedure, evaluated on large scale, through French interlaboratory trials (1977-85), exhibiting net improvement of the dispersion of overall data.Labs were asked to perform with their local thromboplastin and method, the PT of a human lyophilized plasma 86 H/I, originated from long term antivitarnines-K (AVK) treated patients. Results were expressed *in time ; *in % activity, according to the traditional procedure based on saline dilutions of normal plasma ; *in INR using the ISI of the local reagent calibrated by the manufacturer. Calibrated plasmas procedure allow the determination of corrected activity ; *in % activity and INR, according to the linear calibration curve obtained from the PT of 2 reference calibrated plasmas with determinated activities in INR and % activity. These RCP were provided with and tested under the same conditions as plasma 86 H/I6 (2 systems of RCP : AVK and artificially depleted).Statistical analysis shows that the "RCP" procedure leads to the best improvement of the interlaboratory variation for the overall data, and the best uniformization of mean results, whatever the way of expression (%, INR), the thromboplastin brand, and the method of PT testing. Results play also in favour of a system of AVK reference plasmas, giving a better grouping than the artificial calibrated plasmas. The INR system nevertheless provides a common scale of data reporting, but might hold profit from an efficient procedure of standardization, such as the calibrated AVK plasmas procedure.Coefficient of variation (CV) expressed in %. Overall data PT of 86 H/I. French Etalonorme Survey.