Transfusion reactions after whole blood transfusion in Norway, 2021-2024: A report from the Norwegian Hemovigilance...

Whole blood (WB) transfusion for major hemorrhage in Western civilian settings has seen a resurgence over the past two decades. This study aims to determine the rate and type of adverse reactions (ARs) following WB transfusion in Norway between 2021 and 2024.

This retrospective quality surveillance study analyzed, validated, and aggregated all digital reports of ARs after WB transfusion submitted to the Norwegian Hemovigilance system.

Seven ARs were identified, corresponding to an incidence rate of 2.53 per 1000 WB transfusions (7 per 2766 transfusions) or 0.253% (95% CI: 0.123%-0.521%). Three cases were classified as acute hemolytic transfusion reactions: one due to ABO minor incompatibility, one to anti-Jk^a, and one associated with an unidentified red blood cell alloantibody. One case involved respiratory distress and was diagnosed as transfusion-associated dyspnea. Two reactions were allergic: one mild and one fulfilling the criteria for transfusion-associated anaphylaxis. The most severe case involved cardiac arrest, probably due to hyperkalemia and hypocalcemia following massive transfusion, but the patient made a full recovery after defibrillation.

These findings indicate that WB transfusion in Norway is safe. However, there are inherent risks for blood transfusion in general and also risks more specific to WB transfusion. These include the presence of red blood cell alloantibodies anti-A and anti-B combined with approximately 250 mL plasma from a single donor. Accurate and timely hemovigilance work is important to safeguard patient outcomes and provide a foundation for targeted risk mitigation strategies for WB transfusion.