The essence of patient haemovigilance is the recognition, management and prevention of adverse transfusion reactions. It is essential that staff performing transfusions are trained to promptly recognize transfusion reactions and to take immediate action to prevent progression of symptoms and to treat the patient. The ultimate challenge of haemovigilance is to identify risks in order to prevent reactions.  

Adverse events: transfusion reaction reporting

Reporting requirements may vary depending on the national haemovigilance system. Some systems require reporting of all adverse transfusion reactions, some require reporting only of serious reactions, some only of fatalities. Each system must decide the appropriate reporting threshold and their capacity to receive reports. If the central reporting office does not have the capacity to process and analyse all reports, then appropriate adjustments should be made – for example, only reporting serious adverse events.  

Adverse event investigation

The investigation of adverse events is critical to ensuring patient safety, preventing further harm, and maintaining a high-quality transfusion environment. The results of these investigations should be turned into educational opportunities (without blame) to inform staff of potential risks, to improve practice, and to lead to the development of safer systems. Prevention of future adverse events should be the goal of all investigations. There are many resources available for investigation, including root cause analysis and the “five whys” (6). 

Report form templates

Properly designed adverse event and reaction report forms can assist in the recognition and classification of events and may be the first step in providing data to the haemovigilance surveillance programme. Transfusion reaction forms should include sufficient information to classify transfusion reactions, including recipient demographics (age, gender, underlying medical conditions, relevant medications) and implicated components (volumes infused, signs and symptoms, pertinent laboratory results, fluid balance, vital signs, radiographic examination reports and treatment). Forms relating to adverse events should capture the nature of the error or event, systemic factors that contributed to the event and the results of local incident investigations. Many templates and forms are available as part of the WHO guide to establishing a national haemovigilance system.  

Transfusion-transmitted infections

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Standardized definitions

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Adverse event/reaction reporting

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