Les complications respiratoires de la transfusion

Respiratory complications of blood transfusion have several possible causes. Transfusion-Associated Circulatory Overload (TACO) is often the first mentioned. Transfusion-Related Acute Lung Injury (TRALI), better defined since the consensus conference of Toronto in 2004, is rarely mentioned. French incidence is low. Non-hemolytic febrile reactions, allergies, infections and pulmonary embolism are also reported. The objective of this work was to determine the statistical importance of the different respiratory complications of blood transfusion. This work was conducted retrospectively on transfusion accidents in six health centers in Champagne-Ardenne, reported to Hemovigilance between 2000 and 2009 and having respiratory symptoms. The analysis of data was conducted by an expert committee. Eighty-three cases of respiratory complications are found (316,864 blood products). We have counted 26 TACO, 12 TRALI (only 6 cases were identified in the original investigation of Hemovigilance), 18 non-hemolytic febrile reactions, 16 cases of allergies, 5 transfusions transmitted bacterial infections and 2 pulmonary embolisms. Six new TRALI were diagnosed previously labeled TACO for 2 of them, allergy and infection in 2 other cases and diagnosis considered unknown for the last 2. Our study found an incidence of TRALI 2 times higher than that reported previously. Interpretation of the data by a multidisciplinary committee amended 20 % of diagnoses. This study shows the imperfections of our system for reporting accidents of blood transfusion when a single observer analyses the medical records.     

Post-donation information and haemovigilance reporting for COVID-19 in Greece: Information supporting the absence of SARS-CoV-2 possible transmission through blood components

BackgroundAlthough the SARS-CoV-2 virus is transmitted mainly through the respiratory tract, possible transmission by transfusion from asymptomatic carriers should be explored. As yet there are no reports of transfusion transmission of COVID-19. Haemovigilance findings within a three-month surveillance period during the new coronavirus pandemic are presented.Materials and methodsDue to great demand and shortage, blood sessions in outpatient facilities were organized during the high prevalence period of COVID-19, alongside a national plan to monitor the evolving public health situation by random molecular screening of high-risk groups of the population. Haemovigilance protocols were implemented as well as surveillance for any COVID-19 case reported post-transfusion. A 14-day quarantine and follow-up molecular and antibody testing of any COVID-19 positive case was obligatory.ResultsPost-donation, post-transfusion information and molecular testing of swab samples collected from three asymptomatic donors at risk for COVID-19, revealed the case of an immunosupressed patient who had been transfused with whole blood derived platelets from a donor subsequently diagnosed with COVID-19. The recipient exhibited no symptoms of the disease. Molecular and antibody testing results were negative.ConclusionHaemovigilance provided information supporting the absence of transfusion transmission of COVID-19, thus strengthening the hypothesis that, even if it cannot yet be definitively ruled out, COVID-19 is not transmitted through blood transfusion. As of early June 2020, a perfect test does not exist, therefore haemovigilance along with the implementation of strict proactive measures is crucial to identify eluding asymptomatic individuals and ensure blood safety during the pandemic.     

Amotosalen-inactivated plasma is as equally well tolerated as quarantine plasma in patients undergoing large volume therapeutic plasma exchange

A retrospective – single center – survey compared tolerance of individual donor therapeutic plasma in a series of 88 patients principally presenting with thrombotic microangiopathy; all patients underwent therapeutic plasma exchange (TPE) performed with more than 90% of either of two types of plasma preparations. One plasma type used in TPE was prepared with pathogen reduction by amotosalen addition and UVA illumination, and the other one was non-manipulated (quarantine plasma). Both types of plasma were single donor. Occurrences of adverse reactions were equally low in either arm (amotosalen: 9 in 4689 bags of ～200 mL [0.019] versus quarantine: 2 in 828 bags [0.024]), confirming the safe use of amotosalen inactivated therapeutic plasma for TPE.     

血液预警系统综述

对血液预警系统的定义、作用及各国血液预警系统现状进行了介绍,旨在为我国血液预警系统的建立提供借鉴。     

L’hémovigilance française de 1994 à nos jours : évolution et perspectives

Born in France in 1993, haemovigilance aims at monitoring the blood transfusion chain from the donor to the recipient, receiving labile blood products. It differs from the other vigilances due to its organization and its completeness dealing with the collected information. Prior to the European directive, the French agency created a new gravity level: grade 0, aiming at reporting and analyzing the blood transfusion chain dysfunction. Thus, haemovigilance gradually integrates the management of the risks and is given new missions in hospitals and private hospitals. One of its first actions will be to achieve an a-priori analysis, preventing the risks throughout the blood transfusion chain. Such crosscutting missions will be used to manage the coordination of vigilance and in some cases identity monitoring. Haemovigilance may be a key player in identity monitoring because patients’ immunology-hematological data base can make it possible to confirm or deny a patient's identity (misused identity or homonyms). Haemovigilance is going to meet other challenges such as the training of health professionals’, the implementation of patients’ blood management and the periodic revision of the blood transfusions bulletin. A new crosscutting medical profession appears in some countries: blood transfusion practitioner. It combines vigilance, risk management, support for the therapeutic blood transfusions, health professionals training and the evaluation of practices and results. A final mission would be for haemovigilance to be responsible for medicinal products derived from human blood to allow a better monitoring of plasma transfusions.     

Hémovigilance et sécurité transfusionnelle en opération extérieure

The French military blood institute (FMBI) is the only military blood supplier in France. FMBI operates independently and autonomously under the Ministry of Defense's supervision, and accordingly, to the French, European and NATO technical and safety guidelines. FMBI is in charge of the collection, preparation and distribution of blood products to supply transfusion support to armed forces, especially during overseas operations. In overseas military, a primary physician is responsible for haemovigilance in permanent relation with an expert in the FMBI to manage any adverse reaction. Additionally, traceability of delivered or collected blood products during overseas operation represents a priority, allowing an appropriate management of transfusion inquiries and assessment of practices aiming to improve and update procedures and training. Transfusion safety in overseas operation is based on regular and specific training of people concerned by blood supply chain in exceptional situation.     

An overview of red blood cell and platelet alloimmunisation in transfusion

Post-transfusion alloimmunisation is the main complication of all those observed after one or more transfusion episodes. Alloimmunisation is observed after the transfusion of red blood cell concentrates but also of platelet concentrates. Besides alloimmunisation due to antigens carried almost exclusively by red blood cells such as those of the Rhesus-Kell system, alloimmunisation often raises against HLA antigens; the main responsibility for that, apart from platelet transfusions, lies with residual leukocytes in the products transfused, hence the central importance of effective leukoreduction right from the blood product preparation stage. Alloimmunization is not restricted to transfusion, but it is also observed during pregnancies, carrying out microtransfusions of blood from the fetus immunizing the mother through the placenta (in a retrograde way). Preexisting maternal-fetal immunization can complicate a transfusion program and intensify the creation of alloantibodies in several blood and tissue group systems. The occurrence of autoantibodies, created by several pathogenic reasons, can also interfere with the propensity of certain recipients of blood components to produce alloantibodies. The genetic condition of individuals is in fact strongly linked to the ability or not to recognize antigenic variants foreign to their own biological program and mount an alloimmune response. Some hemoglobin diseases, in carriers of which transfusions can be iterative and lifelong, are complicated by frequent alloimmunizations and amplification of the complications of these alloimmunizations, imposing even stricter transfusion rules. This review details the mechanisms favoring the occurrence of alloimmunization and the immunological principles for the production of molecular and cellular tools for alloimmunization. It concludes with the main preventive measures available to limit the occurrence of these frequent complications of varying severity but sometimes severe.