JPAC Joint United Kingdom (UK) Blood Transfusion and Tissue Transplantation Services Professional Advisory Committee

5: Adverse effects of transfusion



  • Modern blood transfusion is very safe but preventable death and major morbidity still occurs.
  • Inappropriate decisions to transfuse put patients at unnecessary risk of transfusion errors, reactions and transfusion-transmitted infection.
  • Identification errors (of patients, blood samples and blood components) by hospital staff are the root cause of most ‘wrong blood into patient’ incidents, including ABO-incompatible transfusions.
  • Severe acute transfusion reactions are the most common cause of major morbidity. These include immunological reactions (predominantly allergy/anaphylaxis, haemolytic reactions and lung injury), circulatory overload and rare bacterial contamination of blood components.
  • If a serious transfusion reaction is suspected – stop the transfusion; assess clinically and start resuscitation if necessary; check that the details on the patient’s ID band and the compatibility label of the blood component match; call for medical assistance; contact the transfusion laboratory.
  • Transfusion-transmitted infection is now a very rare event, underpinned by voluntary donation, donor selection procedures and microbiological testing, but constant vigilance is required as new threats emerge.
  • Variant CJD transmission by blood has had a major impact on transfusion practice in the UK although the risk appears to be receding.


Compared with many medical and surgical procedures modern blood transfusion is extremely safe but deaths and major morbidity still do occur. Errors in the identification of patients, blood samples and blood components are the root cause of many preventable serious adverse events (see Chapter 4). Around 1 in 13 000 blood component units is transfused to the wrong patient (not always with adverse consequences) and up to 1 in 1 300 pre-transfusion blood samples are taken from the wrong patient.

Serious acute transfusion reactions are often unpredictable but patients are put at unnecessary risk by inappropriate decisions to transfuse. In its 2012 Annual Report, the UK Serious Hazards of Transfusion haemovigilance scheme (SHOT – described 252 incidents of ‘incorrect blood component transfused’ (each underpinned by 100 near misses). Ten ABO-incompatible transfusions (all due to clinical errors) and 145 incidents of ‘avoidable, delayed or under-transfusion’ were reported. There were nine transfusion-related deaths (six associated with transfusion-associated circulatory overload) and 134 cases of major morbidity (most often following acute transfusion reactions).

Transfusion-transmitted infection is now a rare event but there is no room for complacency as the emergence of new infectious agents requires constant vigilance.