Learning objectives

• Describe the different types of transfusion reactions
• Recognize the signs of the different types of transfusion reactions
• Take preventative measures against transfusion reactions
• Manage the occurrence of transfusion reactions

Definition & mechanisms

• Transfusion reactions are the most frequent adverse event associated with the administration of blood products, occurring in up to one in 100 transfusions
• There are several types of adverse reactions:
  • Allergic/Anaphylactic reactions
  • Acute hemolytic reactions
  • Delayed hemolytic reactions
  • Febrile non-hemolytic reactions
  • Hyperhemolytic reactions
  • Hypotensive reactions
  • Massive transfusion-associated reactions
  • Post-transfusion purpura
  • Septic reactions
  • Transfusion-associated circulatory overload
  • Transfusion-associated graft versus host disease
  • Transfusion-associated necrotizing enterocolitis
  • Transfusion-related acute lung injury

Signs & symptoms

Prevention

• Comprehensive training of staff
• Close adherence to blood handling and administration policies
• Laboratory testing
• Prospective monitoring and planning
• A restrictive transfusion strategy to avoid unnecessary transfusions

Management

Suggested reading

• Delaney M, Wendel S, Bercovitz RS, et al. Transfusion reactions: prevention, diagnosis, and treatment. Lancet. 2016;388(10061):2825-2836.

Clinical updates

Metcalf et al. (JAMA, 2025) report updated AABB/ICTMG international platelet transfusion guidelines supporting a restrictive transfusion strategy, based on 21 RCTs and 13 observational studies showing no increase in mortality or major bleeding with lower transfusion thresholds. The recommendations lower prophylactic platelet triggers to < 10,000/μL in stable oncology and critical care patients, < 25,000/μL in non-bleeding neonates, and discourage transfusion in settings such as dengue without bleeding, cardiovascular surgery without thrombocytopenia, and intracranial hemorrhage with platelet counts > 100,000/μL. By reducing unnecessary platelet exposure, the guidelines aim to decrease transfusion-related complications while preserving limited blood product resources and improving overall transfusion safety.

• Read more about this study HERE.