[The blood donors' haemovigilance in France]

Donor Safety in Haemapheresis: Development of an Internet-Based Registry for Comprehensive Assessment of Adverse Events from Healthy Donors

BACKGROUND

Currently, there is an extensive but highly inconsistent body of literature regarding donor adverse events (AEs) in haemapheresis. As the reports diverge with respect to types and grading of AEs, apheresis procedures and machines, the range of haemapheresis-related AEs varies widely from about 0.03% to 6.6%.

METHODS

The German Society for Transfusion Medicine and Immunohaematology (DGTI) formed a 'Haemapheresis Vigilance Working Party' (Arbeitsgemeinschaft Hämapheresevigilanz; AGHV) to create an on-line registry for comprehensive and comparable AE assessment with all available apheresis devices in all types of preparative haemapheresis: plasmapheresis (PLS), plateletpheresis (PLT), red blood cell apheresis, all kind of leukaphereses (autologous/allogeneic blood stem cell apheresis, granulocyte apheresis, lymphocyte/monocyte apheresis) and all possible types of multi-component apheresis. To ensure the comparability of the data, the AGHV adopted the 'Standard for Surveillance of Complications Related to Blood Donation' from the International Society for Blood Transfusion in cooperation with the International Haemovigilance Network (IHN) and the American Association of Blood Banks for AE acquisition and automated evaluation. The registry is embedded in a prospective observational multi-centre study with a study period of 7 years.

RESULTS

A preliminary evaluation encompassed the time period from January, 2012 to December, 2015. During this time, the system proved to be safe and stable. Out of approximately 345,000 haemaphereses 16,477 AEs were reported (4.9%) from 20 participating centres. The majority of AEs occurred in PLSs (63%), followed by PLT (34.5%) and SC (2.2%). Blood access injuries (BAI) accounted for about 55% of the supplied AEs, whereas citrate toxicity symptoms, vasovagal reactions and technical events (e.g. disposable leakages, software failures) rather equally affected haemaphereses at 8-15%. Out of 12,348 finalized AEs, 8,759 (70.1%) were associated with a procedure-related break-off, with BAI being the prevailing cause (5,463/8,759; 62.4%). An automated centre- and procedure-specific AE evaluation according to the latest IHN standard and AGHV pre-settings is available within a few minutes.

CONCLUSIONS

An on-line electronic platform for comprehensive assessment and centre-specific automated evaluation of AEs in haemaphereses has been developed and proved to be stable and safe over a period of 4 years.

Improving platelet transfusion safety: biomedical and technical considerations

Platelet concentrates account for near 10% of all labile blood components but are responsible for more than 25% of the reported adverse events. Besides factors related to patients themselves, who may be particularly at risk of side effects because of their underlying illness, there are aspects of platelet collection and storage that predispose to adverse events. Platelets for transfusion are strongly activated by collection through disposal equipment, which can stress the cells, and by preservation at 22 °C with rotation or rocking, which likewise leads to platelet activation, perhaps more so than storage at 4 °C. Lastly, platelets constitutively possess a very large number of bioactive components that may elicit pro-inflammatory reactions when infused into a patient. This review aims to describe approaches that may be crucial to minimising side effects while optimising safety and quality. We suggest that platelet transfusion is complex, in part because of the complexity of the "material" itself: platelets are highly versatile cells and the transfusion process adds a myriad of variables that present many challenges for preserving basal platelet function and preventing dysfunctional activation of the platelets. The review also presents information showing--after years of exhaustive haemovigilance--that whole blood buffy coat pooled platelet components are extremely safe compared to the gold standard (i.e. apheresis platelet components), both in terms of acquired infections and of immunological/inflammatory hazards.

[Blood transfusion: control of infectious risks]

From blood donor collection to transfusion of the recipient, there are several layers of protection of the blood supply. These measures combined with huge progresses over the three past decades in pathogen discovery and blood testing for specific pathogens (human immunodeficiency virus (HIV), hepatitis B (HBV) and C (HCV) viruses, Human T-cell leukemia virus (HTLV)), provide the greatest safety. With the implementation of serological and molecular testing, at least in high-income countries, transfusion-transmitted infections have become extremely rare. However, for pathogen agents, which are not tested and especially those which are responsible for emerging infectious disease, it became apparent that full control of infectious disease had not been achieved. In addition, the immune status of the recipient has also an impact in the outcome of infectious diseases transmitted by transfusion. Blood safety is based on several measures: education and deferral of donors with risk factors for transmissible disease, blood testing, pathogen reduction interventions, and patient blood management. This paper proposes a review of the residual risk of transmission of infectious diseases by transfusion and of the additional interventions able to further reduce it.

[The different types of therapeutic plasma are equivalent?]

In France, three varieties of therapeutic plasma are being processed, distributed and delivered, currently; however, many more varieties are in use worldwide, which go by the property of labile blood component or plasma derived medicines. For one type of component (one given name), several devices and bags and so on are used to concur to its process, which makes that one type of therapeutic plasma may significantly differ from one production setting to one other. This may affect (more or less) the component properties as well as the possibly reported adverse events. This review aims thus, firstly at stressing on the difficulty in comparing data obtained in different contexts, and secondly at making the point on future directions to process therapeutic plasma.