Acute Non-Immune Hemolytic Transfusion Reactions
Description
Acute non-immune Hemolytic Transfusion Reactions (non-immune HTR) occur when hemolysed red cells that are serologically compatible are transfused. Hemolysis can be caused by physical or chemical destruction of red blood cells including:
- freezing (e.g., transporting blood at improper temperatures or placing RBC beside a freezer pack/ice with no insulation between the frozen pack/ice and the blood)
- heating (e.g., transfusing RBC using a blood warmer with too high a temperature)
- hemolytic drug or solution added to blood (e.g., if mixed with RBC, 5% dextrose, 50% dextrose, and hypotonic sodium solutions, this can cause red cells to hemolyse)
- mechanical trauma from intraoperative blood collection devices or cardiopulmonary pump-oxygenators
- older RBCs infused under pressure through a small bore needle
- inadequate deglycerolization of frozen RBC
- transfusion of outdated blood
- red cell fragility due to hemoglobinopathies or enzyme deficiencies in the donor, e.g., glucose-6-phosphate dehydrogenase deficiency
NOTE: An atypical form of acute hemolytic transfusion reaction has been reported in patients with Sickle Cell Disease (SCD) following transfusion of compatible RBC. The pathophysiology is not well understood; hypotheses include a bystander hemolysis mechanism, suppression of erythropoiesis, or hyperactive macrophages (see Further Reading).
Incidence
The incidence of non-immune Hemolytic Transfusion Reactions is unknown but they occur only rarely.
Preventing non-immune Hemolytic Transfusion Reactions depends on proper handling, storage, and administration of blood components