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Febrile, Allergic and Hypotensive Reactions (FAHR) Cumulative Data


The reactions assessed are isolated febrile type (not associated with other specific reaction categories), allergic and hypotensive reactions occurring up to 24 hours following a transfusion of blood or components, for which no other obvious cause is evident.

SHOT has collected data on febrile, allergic and hypotensive reactions (FAHR) since 1996. Originally, this category was called acute transfusion reactions (ATR).

Since 2012 SHOT has excluded ‘mild reactions’, and now only collects data on moderate or severe reactions according to the International Society for Blood Transfusion/International Haemovigilance Network (ISBT/IHN) definitions.


Recent Recommendations

  • Pooled platelets suspended in platelet additive solution (PAS) are associated with a reduction in allergic response (BSH Estcourt et al. 2017). Hospitals should consider preferential use of readily available pooled platelets suspended in PAS in patients with a history of allergic reactions. This should include paediatric patients where apheresis platelets are usually the platelet component of choice. If reactions continue, despite antihistamine cover, then platelets re-suspended in 100% PAS can be supplied
  • Transfusion teams should audit appropriateness of treatment given for acute transfusion reactions
  • Transfusion reaction reporting forms should be designed to help reporters classify the type of reaction, to guide appropriate investigation
  • The possibility of a febrile or allergic reaction should be explained to patients/guardians when taking consent for transfusion with provision of relevant patient information leaflets
  • Action: Hospital transfusion teams

FAHR Resources

FAHR Annual Report Chapters