In vitro characteristics of cryopreserved platelet concentrates reconstituted by fresh frozen or lyophilized plasma.

BACKGROUND AND OBJECTIVES: Six percent dimethyl sulfoxide (DMSO) cryopreservation of platelet concentrates (PCs) allow longer storage of PCs but require time-consuming post-thaw washing. An alternative process based on removing supernatant before freezing has been implemented in several centres worldwide. We assessed the in vitro characteristics of cryopreserved PCs (CPPs) prepared according to this latest process using either French lyophilized plasma (FLyP) or fresh frozen plasma (FFP) for reconstitution. FLyP provides additional benefits to the process due to its logistical constraints and quick availability. MATERIALS AND METHODS: Apheresis PCs (n=16) and buffy coat PCs (n=16) were cryopreserved in 6% DMSO. After storage at -80°C, PCs were thawed and reconstituted with FFP or FLyP. Volume, residual leukocytes, total platelet counts (TPCs), post-thaw recovery, biochemical parameters, and DMSO concentration were assessed. Platelet functions were analysed by swirling index, viscoelastometric assay and CD62P quantification. RESULTS: After reconstitution, TPC was above 2.1011/CPs; recovery was 78±14% with no significant difference between FFP and FLyP. Glucose and lactate levels were not different between plasmas, whereas FLyP-CPPs exhibited a significant increase in LDH and significantly lower pH. Residual DMSO was 8±4G/L. Functional analysis revealed significant differences between FFP and FLyP-CPPs, with lower clot firmness and increased clot initiation. Activation of platelets was not higher in FLyP-CPPs. CONCLUSION: Preparing CPPs according to this "new" process fulfilled the French legal criteria regardless of the type of plasma. Differences highlighted between FFP-CPPs and FLyP-CPPs were unlikely to be of clinical relevance.

Rational and design of the T-STORHM Study: A prospective randomized trial comparing fresh whole blood to blood components for acutely bleeding trauma patients.

Massive hemorrhage remains the main cause of preventable death in combat settings and is also the main cause of year loss in developing countries. The management of these patients relies on blood transfusion and surgery. Time is a key factor, related to survival. Recent events highlight the need to be more efficient in the transfusion supply during terror attacks or mass casualties in civilian settings. Blood components therapy with a 1:1:1 ratio is associated with a decrease of mortality but encounters many logistic issues in those circumstances. Whole blood provides in one bag all the blood components in physiologic proportions with minimal amount of additive solution. Whole blood has been implemented in military as well as civilian settings worldwide. However, direct comparisons with component therapy in prospective clinical trials are scarce. Here we present the rational and the design of the T-STORHM (Trauma-Sang TOtal dans les Hémorragies Massives) trial. This prospective randomized multicentric clinical trial will test low titer group O whole blood to components therapy in the in-hospital management of trauma patients with massive hemorrhage. Sample size calculation, primary and secondary endpoints as trial blood products preparations are discussed. The trial is expected to start in 2019 in 6 civilians and military trauma centers. The French Military Health Service is promoting the study in collaboration with the French transfusion public service (Établissementfrançaisdusang).

[Preparation of pooled granulocytes concentrates from whole blood buffy coats (PGC) as an alternative to apheresis]. / Le mélange de concentré de granulocytes de sang total (MCGST) comme alternative au concentré de granulocytes d'aphérèse (CGA).

BACKGROUND: The collection of granulocytes by apheresis requires volunteer donor stimulation by corticoids and the use of HES, a compound which is currently challenged by potential safety issues. Preparation of pooled granulocytes concentrates from whole blood buffy coats (PGC) represent an alternative to apheresis with a better benefit/risk for the donors. METHOD: Whole blood is collected in a bottom and top blood bag for buffy coat preparation. After centrifugation and separation, buffy coat are obtained. Twenty ABO matched buffy coats are selected for processing into one PGC. Four pools of five buffy coats were made, platelet additive solution is added to each pool, mixed gently and centrifuged. The red cell residue, supernatant and granulocyte rich layer are separated. Two granulocyte rich layers are pooled and added with 70mL of ABO matched plasma from the initial donations (=PGC10). The final PGC (=PGC20) is obtained by pooling two PGC10 into a platelet storage bag. Neutrophil content and in-vitro functionality are assessed at day of preparation (D1) and at expiry hour, 48 hours after collection (D2). RESULTS: On N=18, mean: Volume=408±4mL, 2.2*1010±0.24 neutrophils, Hematocrit=18%±3%, 4.7*1011platelets. Viability is well preserved: 95%±6% day of PGC preparation, 85%±7% after 24h of storage (D2). Functionality (ROS production measurement) is well preserved: 1.36±0.25 at D1 and 1.38±0.18 at D2. Expression and modulation of adhesion molecules after stimulation are normal at D1 and slightly decreased at D2 but still normal. CONCLUSIONS: PGC20 in vitro characteristics are in conformance with the EDQM guide (V19) and similar to apheresis for granulocytes content and hematocrit. The viability and two mean indicators which explore neutrophil function are well maintained during PGC preparation and after 24 hours of storage.

Quality control of apheresis platelets: a multicentre study to evaluate factors that can influence pH measurement.

BACKGROUND AND OBJECTIVES: Blood operators routinely monitor the pH of apheresis platelets as a marker of the so-called storage lesion, which can result from manufacturing problems. It is also suspected that some donor characteristics can increase the risk of poor platelet storage. To explore this hypothesis, we analysed a large, multinational data set of quality control (QC) pH test results on apheresis platelets. MATERIALS AND METHODS: For the period between September 2011 and August 2014, seven blood operators in Canada, the USA, the Netherlands, the United Kingdom, France and Australia provided pH QC test results and donor characteristics on a total of 21,671 apheresis platelets. RESULTS: Some variations in pH distribution between blood operators were in part explained by differences in collection, processing and testing methods. Younger age and female gender were significantly associated with a pH value below the 10th percentile. Among donors who had two or more pH measurements (n = 3672), there was a strong correlation between pH results (r = 0·726; P < 0·0001). CONCLUSION: The strong intradonor correlation of pH measurements and the association between donor characteristics and pH results suggest that donor factors play a role in the quality of platelets.

[Innovative technology and blood safety]. / Innovations technologiques et sécurité transfusionnelle.

If technological innovations are not enough alone to improve blood safety, their contributions for several decades in blood transfusion are major. The improvement of blood donation (new apheresis devices, RFID) or blood components (additive solutions, pathogen reduction technology, automated processing of platelets concentrates) or manufacturing process of these products (by automated processing of whole blood), all these steps where technological innovations were implemented, lead us to better traceability, more efficient processes, quality improvement of blood products and therefore increased blood safety for blood donors and patients. If we are on the threshold of a great change with the progress of pathogen reduction technology (for whole blood and red blood cells), we hope to see production of ex vivo red blood cells or platelets who are real and who open new conceptual paths on blood safety.

[The EFS metrology: From the production to the reason]. / Métrologie à l'EFS : de la production à la raison.

In order to answer statutory requirements and to anticipate the future needs and standards, the EFS is committed, since a few years, in a process of harmonization of its metrology function. In particular, the institution has opted for the skills development by internalizing the metrological traceability of the main critical quantities (temperature, volumetric) measurements. The development of metrology so resulted in a significant increase in calibration and testing activities. Methods are homogenized and improved through accreditations. The investment strategies are based on more and more demanding specifications. The performance of the equipments is better known and mastered. Technical expertise and maturity of the national metrology function today are assets to review in more informed ways the appropriateness of the applied periodicities. Analysis of numerous information and data in the calibration and testing reports could be pooled and operated on behalf of the unique establishment. The objective of this article is to illustrate these reflections with a few examples from of a feedback of the EFS Pyrénées Méditerranée. The analysis of some methods of qualification, the exploitation of the historical metrology in order to quantify the risk of non-compliance, and to adapt the control strategy, analysis of the criticality of an instrument in a measurement process, risk analyses are tools that deserve to be more widely exploited for that discipline wins in efficiency at the national level.

National French observatory of the quality of blood components for transfusion.

PURPOSE: Since 1998, prestorage leucoreduction of cellular blood components (BC) is mandatory in France. The French Blood Service needs to follow the data on the quality of the BC prepared by blood centers. This article gives an overview of the quality control (QC) data from 2001 to 2006. MATERIAL AND METHODS: QC data are submitted to a central data bank by each centre. The data are stratified according to preparation process for analysis of key performance criteria - residual leukocytes and haemoglobin or platelet content. BC preparation processes, methods for measuring haemoglobin and platelet content, and for counting residual leukocytes are those routinely employed by centers. RESULTS: The preparation process of red cell concentrates (RCC) influences the haemoglobin content: 57.6+/-6.8 g per unit versus 50.9+/-5.4 g per unit for whole blood or RCC filtration, respectively. Apheresis RCC exhibits a reduced variability (51.2+/-3.4 g per unit). For apheresis platelet concentrates, the median residual leukocyte count remains low for all separators (0.019-0.044 x 10(6)leukocytes per unit, in 2006). However, the percentage of units exceeding 1 x 10(6)leukocytes per unit is significantly higher with one separator (1.8% versus 0.8%, in 2006). For pooled buffy-coat derived platelets, we observed a significant increase in platelet recovery throughout the years (0.66-0.77 x 10(11)platelets per buffy-coat in 2001 and 2006, respectively). CONCLUSION: Our QC data show an overall compliance with the requirements for cellular BC. Our data bank is useful to inform on the performance of leucoreduced BC preparation processes carried out with market available devices.

Quality of leucoreduced red blood cell concentrates: 5 years of follow-up in France.

BACKGROUND: Since 1998, prestorage leucoreduction of all cellular blood components has been made mandatory in France. The French blood service needed to follow the data on the quality of the blood components prepared by blood centres. MATERIAL AND METHODS: Quality control (QC) data were submitted to a central data bank by each blood centre. The data were stratified by preparation method for analysis of key performance criteria - residual white blood cell (WBC) and total haemoglobin content. The red blood cell (RBC) preparation processes and the methods for measuring haemoglobin content and residual WBC count were those routinely employed by blood centres. Each year, more than 15,500 RBCs were tested. RESULTS: Red blood cells had a mean haemoglobin content between 53.6 and 54.9 g/unit depending on the year (2001 to 2005). The requirement of 40 g/unit was reached for about 99% of units. The haemoglobin content was influenced by the preparation process: 56.8 +/- 6.9 vs. 50.6 +/- 5.6 g/unit in average for whole blood filtration or RBC filtration, respectively. Apheresis RBCs exhibited a reduced variability (51.8 +/- 3.1 g/unit). The median residual WBC count remained low (0.046 to 0.057 x 10(6) WBCs/unit), and the percentage of RBC units exceeding the 1 x 10(6) WBCs/unit cut-off ranged from 1.5 to 0.6% depending on the year. A seasonal pattern was observed, with a significant increase (P < 0.001) of the median residual WBC count and of the percent of non-conforming units during the summer months. CONCLUSION: Our QC data suggest an overall compliance with the standard. Our data bank is useful to inform on the performance of leucoreduced RBC preparation processes carried out with market available devices.

[Quality control of labile blood products. Why and howto properly take a specimen? Labile Blood Products Group of the French Blood Transfusion Society]. / Le contrôle de qualité des produits sanguins labiles. Pourquoi et comment bien prélever un échantillon? Groupe de produits sanguins labiles de la Société française de transfusion sanguine.

This article reviews the various techniques of sampling used for the quality control of blood cell products. The importance of this stage for the validity of quality control results is emphasized. Three sampling methods, i.e., stripping, the sterile connection of sampling bag and the destructive method, are described in the form of operating modes and analyzed according to their advantages and drawbacks. The results of a comparative study carried out by the working group 'Blood Cell Products' of the French Society of Blood Transfusion are presented, showing that each method is valid and permits one to obtain a representative sample of the product to be controlled. Thus the diversity of the sampling methods allows us to select the one most adapted to the product to be controlled and to the analyses to be carried out afterward.

[Leukocyte depletion]. / La déleucocytation.

Leukodepletion is a significant factor of improvement of the quality and safety of blood cell components. By reducing residual leukocytes in the products to a rate below 1 million per unit, the risks of transmitting intralymphocyte viruses, provoking shivers and hypothermia reactions, and inducing anti-HLA alloimmunization are diminished, as well as bacterial contamination risks. The constant improvement of the performance and the use of leukodepletion filters allows this technique to be generalized to all red blood cell and platelet concentrates. Leukocytes retention devices on these filters are numerous and sensitive to the conditions for material use. Implementation of Leukodepletion at production stage must be carried out in a mastered framework of quality assurance.