Case-control study of immediate and delayed vasovagal reactions in blood donors.

BACKGROUND AND OBJECTIVE(S): Vasovagal reactions (VVRs) are the most common adverse events associated with blood donations. To assess the relative importance of VVR risk factors, a retrospective case-control study of severe immediate and delayed VVRs was performed. STUDY DESIGN: Vasovagal reactions were defined as immediate when occurring at the transfusion site and as delayed when occurring outside the transfusion site and within 24 h following donation. VVRs with probable or certain imputability and moderate to death severity were considered. One control/case was drawn randomly from among donors without VVR. Explanatory variables (sex, age, body mass index (BMI), donation status, type of phlebotomy) as well as the matching variables (donation region, date) and the interaction term (sex and BMI) were integrated into the multivariate model. RESULTS: In French hemovigilance data collected from 2011 to 2013, 8410 immediate and 833 delayed VVRs occurred among 8 834 214 donations. In multivariate analysis, occurrence of immediate VVR was strongly associated with first-time donation (OR 4·34; 95% CI: 3·93-4·79, P < 0·0001) and the 18-24 age group (OR 2·24; 95% CI: 2·00-2·45, P < 0·0001) and of delayed VVR with women with a normal BMI (OR 7·31; 95% CI: 4·96-10·77, P < 0·0001), overweight BMI (OR 7·89; 95% CI: 4·84-12·87, P < 0·0001) or obese BMI (OR 3·72; 95% CI: 1·42-9·74, P < 0·0001), and in men with an underweight BMI (OR 6·39; 95% CI: 1·56-26·13, P < 0·0001). Apheresis was a risk factor for occurrence of both immediate and delayed VVR. CONCLUSION: Our study highlights that first-time donation by a young person is particularly at risk of immediate VVR while a female donor is at risk of delayed VVR.

[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.

Management of the blood supply for a Jk(a-b-) patient with an anti-Jk3 in preparation for an urgent heart transplant: An illustrative example of a successful international cooperation.

The Kidd blood group system currently comprises two polymorphic and antithetical antigens, Jka and Jkb, and one high-prevalence antigen, Jk3. Jknull individuals do not express any of the Kidd antigens, and are at risk of developing an anti-Jk3 which is known to be dangerous and responsible for acute or delayed hemolytic transfusion reaction. We report a case of an immunized Jknull patient, who was scheduled to undergo a heart transplant. In order to organize his blood provision management, two conference calls were held between the clinical team and the different staff involved in this challenging blood supply. In light of the blood needs, the available resources, and the constraints, a mix of fresh and frozen units were used. As the supply from France was not sufficient, Finland and New Zealand provided the majority of the fresh units. We report here how this international supply chain was organized, including the difficulties that we encountered. Anticipation, communication and flexibility were essential in making this heart transplant possible without needing to transfuse incompatible units.

[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.

[Evaluation of erythrocyte concentrate prescription in a university hospital center]. / Evaluation de la prescription des concentrés de globules rouges dans un centre hospitalo-universitaire.

This prospective study, based on declaratory data, evaluates the appropriateness of red blood cell transfusion prescriptions in a university hospital. Local recommendations written after data collection and the analysis of prescriptions using a blinded method limited the bias related to the declaratory data. The results show that the rate of unjustified prescriptions is 4.2% (95% CI: 2.2%; 6.2%). This rate is statistically (P = 0.032) lower in the department of surgery (1.3%) than in the department of medicine (5.7%). This rate tends to decrease according to the experience of the prescriber (P = 0.06) and varies significantly according to the hemoglobin levels (P = 0.03). The logistic regression, integrating these three parameters, confirms that only the hemoglobin level is significantly related (P < 0.003) to the appropriateness of RBC transfusions. This study also highlights problems not linked to prescriptions, and the hospital created a quality assurance program as a result.

[From the transfusion informationcard to the tracing of blood products]. / De la fiche transfusionnelle à la traçabilité des produits sanguins.

The transfusion sheet established in 1985 with the aim of improving the immunological safety has not fulfilled the goal expected. Furthermore, it is now clear that the immunological safety does not necessarily imply transfusional safety only, though alertness in this field should be maintained. The residual post transfusional risk, though limited, should remain a permanent concern both for the transfuser and the prescriptor. "Haemovigilance" has become an integral part of the transfusional safety. It cannot exist without a trace-back of the blood products. At any time it should be possible to determine: "who received what and from whom?" The blood bank has the responsibility for the link between the donor and the blood product and the clinician has the responsibility of the link between the blood product and the recipient. Both partners must be aware of the absolute necessity of sharing and checking all information. Means for this trace-back exist, sophisticated or not, and more or less costly. It is up to each one to select the most suitable system.

[Management of blood products in obstetric services]. / Gestion des produits sanguins en maternité.

OBJECTIVES: Define the access conditions and mode of use of blood products in the context of the management of immediate postpartum hemorrhage. METHODS: This text is based on the guidelines published by the French National Authority for Health (HAS) and the French National Security Agency of Medicines and Health Products (ANSM) and a literature search in Medline and Cochrane Library databases. RESULTS: Postpartum bleeding, often unpredictable and potentially severe, may represent a challenge for transfusion management decision within an institution. The efficiency of the decision is based on an emergency protocol widely available in each establishment to secure access to blood products, and coordination between teams of clinical and blood transfusion services (Professional consensus). Blood transfusion is not without infectious and immunological risks, each indication must be carefully considered based on clinical and laboratory criteria (Professional consensus). Availability of blood groups and antibody screening results must be checked upon entry to the delivery unit (Professional consensus). If bleeding risk is identified, RAI less than three days is recommended (Professional consensus). Complex immunological situations, including rare blood groups, should be planned and managed with EFS blood centers throughout prenatal period (Professional consensus). CONCLUSION: Transfusion management in postpartum hemorrhage should be a multidisciplinary approach and requires mastery of emergency circuits to obtain promptly blood products.

[Postdonation information: the French fourth hemovigilance sub-process]. / L'information post-don, le quatrième sous-processus de l'hémovigilance.

Postdonation information is the knowledge of information about the donor or his donation, occurring after it, which challenges quality or safety of the blood products stemming from this or other donations. Classical hemovigilance sub-processes concerning donors or recipients adverse events do not cover this topic. France is just about to make it official as a fourth sub-process. Less formal management of postdonation information is already set up for more than ten years. French data of the year 2013 are presented, including the regional notification level and the national reporting one. A significant level of heterogeneity is observed as for other hemovigilance sub-processes. It is mainly due to subjective rather than objective differences in risk appreciation. A real consensual work is expected about it in the future.

[Hepatitis E virus: Blood transfusion implications]. / Virus de l'hépatite E, implications en transfusion sanguine.

Hepatitis E virus (HEV) is a non-enveloped RNA virus transmitted by the fecal-oral route. Autochthonous hepatitis E occurring in developed countries is caused by genotypes 3 and 4 and is a zoonotic infection. Humans are infected mostly after ingestion of undercooked meat from infected animals. Most HEV 3 and 4 infections are clinically inapparent. However, genotype 3 (HEV 3) can lead to chronic hepatitis in immuno-compromised patients such as organ-transplant recipients and patients with haematological malignancies. In Europe, HEV 3 is implicated in transfusion-transmitted HEV infection. In France, as observed in several European countries, prevalence of HEV RNA and specific IgG antibodies are high indicating that viral circulation is important. The systematic HEV NAT screening of blood donations used for preparation of solvent detergent plasma indicate that 1 to 2218 donation is infected by HEV RNA. The need or implementation's impacts of safety measures to prevent HEV transmission by blood transfusion are under reflexion by French's health authorities. The HEV NAT screening is the only available tool of prevention. Alternative strategies are under investigation including individual or mini pool NAT testing all or part of blood donations.

[Assessment of a transfusion emergent risk: the case of HEV]. / Estimation d'un risque transfusionnel émergent: l'exemple du VHE.

BACKGROUND: The risk assessment for blood transfusion is an essential step that must precede any screening strategy of a pathogen transmitted by transfusion. After several cases of HEV transmission by transfusion in France, a risk assessment for this virus was performed. METHODS: We used a method based on the prevalence of HEV-RNA in plasmas collected for the preparation of SD-plasma. To estimate the rate of HEV-RNA positive among all blood donations, data on SD-plasma were adjusted on the following HEV risk factors: gender, age group and region of residence. We assumed that HEV risk factors were the same in plasma donors and whole blood donors. RESULTS: Among 57,101 plasma donations tested for HEV-RNA in 2013, 24 were positive (crude rate of 4.2 per 10,000 donations). After adjustment, the total number of HEV-RNA positive blood donations was estimated at 788, accounting for a rate of 2.65 per 10,000 donations (95% CI: 1.6-3.7) or 1 in 3800 donations (1 in 6,200-1 in 2,700). This rate was 12 times higher in men than in women, increased with age, and varied according to region of residence. CONCLUSION: The risk of blood donation contamination by HEV has been estimated to be 1 in 3800 donations in 2013. An essential input is still missing to assess now the risk in recipients: the minimum infectious dose. Furthermore, the risk in recipients has to be analyzed according to characteristics of transfused patients: presence of anti-HEV immunity, existence of chronic liver disease or immunodeficiency.

[Transfusion of plasma: products-indications]. / Transfusion de plasma: produits-indications.

The use of therapeutic plasma has increased in France by more than 40% since 2002. This growth may be explained by the improvement in transfusion safety, the diminution of the risk of transmission of pathogens and the regained confidence of the physicians in blood products. Therapeutic plasma also benefits from additional procedures to reduce infectious (securisation) or immunological risks (selection of blood donors). Its application in massive transfusions has undergone a significant evolution over the last few years. A proactive attitude favouring early and important use of plasma on the basis of pre-established protocols is advocated henceforth. The prescription of therapeutic plasma for other indications must be guided by the results of biological tests and an evaluation of the haemorrhagic risk. Despite regular updating of the guidelines for good transfusion practice, plasma is still sometimes prescribed for prophylactic purposes in situations where the biological and/or clinical criteria do not justify it. Moreover, it is not recommended to use fresh frozen plasma in cases of deficiency of coagulation factors if the specific concentrates are available as intravenous fluids. Complementary clinical studies will be necessary to evaluate, in certain indications, the real benefits of the transfusion of plasma and the interest of replacing it by concentrates of coagulant factors (fibrinogen, prothrombin complex).

Perioperative platelet transfusion. Recommendations of the French Health Products Safety Agency (AFSSAPS) 2003.

The aim of this paper is to present the recommendations of the Agence Française de Sécurité Sanitaire des Produits de Santé (AFSSaPS; French Safety Agency for Health Products). A panel of experts reviewed and graded the literature on platelet transfusions; recommendations were formulated. Threshold platelet counts (PC) for transfusions in the perioperative context have not been clearly defined and should be determined by the existence of hemorrhagic risk factors. In the case of commonly practiced invasive procedures, the recommendation is to transfuse in order to achieve PC > 50,000 x microL-1. In the absence of platelet dysfunction, regardless of the type of surgery, the standard hemorrhagic risk threshold for surgery is 50,000 x microL-1. It has not been proven that the risk threshold is different according to the type of surgery. For neurosurgery and ophthalmologic surgery involving the posterior segment of the eye, a PC of 100,000 x microL-11 is required. For axial regional anesthesia, a PC of 50,000 x microL-11 is sufficient for spinal anesthesia; a PC of 80,000 x microL-11 has been proposed for epidurals. During massive transfusion, prophylactic platelet infusion cannot be recommended beyond a loss of two blood volumes in less than 24 h (Professional Consensus). As for the therapeutic transfusion of plasma and/or platelets, as much as possible, platelet deficit should be documented with test results (PC and fibrinogen) before transfusing. In the event of bleeding, platelet transfusion may precede plasma infusion. However, although this recommendation has been the subject of several professional consensus agreements, it is not based on any randomized studies. Threshold PC for perioperative transfusions have not been clearly defined and most recommendations are the result of a professional consensus.