Transfusion reactions
Transfusion reactions are a spectrum of immunologic and non-immunologic complications of blood product administration, ranging from a benign febrile reaction to fatal acute hemolysis, anaphylaxis, TRALI, or septic shock. The first step for any reaction is always to stop the transfusion; the type is then distinguished by timing, hemolysis markers, and hemodynamic and respiratory pattern, and each type has a specific treatment and prevention strategy.
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What this article covers
- Overview
Definition: any adverse response to blood product administration, produced by immunologic mechanisms (antibody-antigen reactions, cytokine release, donor leukocyte engraftment) or non-immunologic…
- Epidemiology
Febrile nonhemolytic reaction is most common, up to 1% of episodes, more often after red cell or platelet transfusion than plasma.
- Risk factors
Clerical/identification error: the dominant cause of ABO-incompatible acute hemolytic reactions; high-turnover areas are particularly prone.
- Pathophysiology
Acute hemolytic: preformed recipient antibodies (classically anti-A/anti-B) bind donor erythrocyte antigens, fixing complement and causing intravascular hemolysis proportional to volume transfused…
- Clinical features
Acute hemolytic: fever and flank pain during or shortly after transfusion, plus hematuria/dark urine; can progress to hypotension, DIC, and acute kidney injury; onset minutes to as late as 24 hours.
- Differential diagnosis
Sepsis from a non-transfusion source: fever/hypotension coincident with but not caused by transfusion; distinguished by cultures of patient and returned unit and the pattern relative to infusion.
- Diagnosis
Established by clinical pattern (timing, hemodynamics, respiratory findings) plus hemolysis and culture testing, not one unifying test: acute hemolytic reaction needs a positive direct antiglobulin…
- Management
Stop the transfusion immediately and maintain IV access with normal saline; this is the most important step regardless of cause.
- Complications
DIC and acute kidney injury: the major organ-threatening complications of acute hemolytic reaction, driven by volume transfused before cessation.
- Prognosis
Outcome is time-to-recognition dependent: hemolytic reaction severity is proportional to volume infused before cessation, so early recognition is the strongest determinant.
- Prevention
Positive patient and specimen identification at every step: two-identifier verification at collection and bedside, supported by electronic barcode systems, is the primary prevention for ABO-incompatible hemolytic reactions.
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