Haemolytic Transfusion Reaction (HTR)

Definition

HTR occurs when antibodies in the patient’s plasma react with antigens on transfused allogeneic red blood cells, causing haemolysis.

HTR occurring during, or within 24 hours of, transfusion is classed as acute; a delayed HTR can occur days to weeks after the transfusion.

Symptoms include fever, rigors, chills, hypotension, pain, dyspnoea, tachycardia, nausea, or restlessness; acute HTR can be life-threatening.

Frequency

Rare (≥1 in 10,000 to <1 in 1,000).

Patients with haemoglobinopathies are at a higher risk of HTR.

Reducing the risk

Patients are encouraged to report any unusual sensation experienced during or after their transfusion; they should also be discharged with information about signs and symptoms to look out for and who to contact.

Historical antibodies should be clearly documented in clinical notes and transfusion records including the transfusion laboratory information system, and compatible blood should issued.

Further information and resources

Serious Hazards of Transfusion (SHOT) educational resources:

• SHOT Haemolytic Transfusion Reactions (HTR) Webinar 2021
• SHOT Bite No.14: Transfusion Errors and Reactions in Patients with Haemoglobinopathies
• SHOT Bite No.15: Hyperhaemolysis