++
++
Severe reactions usually involve incompatible mismatches in ABO system that are isoagglutinin-mediated
Most cases are due to clerical errors and mislabeled specimens
When hemolysis occurs, it is rapid and intravascular; most reactions occur in surgical patients under anesthesia
Severity depends on RBC dose
Less severe reactions caused by minor antigen systems
Hemolysis is slower and is mediated by IgG antibodies causing extravascular red blood cell destruction; reactions may be delayed for 5–10 days after transfusion
Duffy, Kidd, Kell, and C and E loci of Rh system are antigens most commonly involved
Most transfusion reactions are not hemolytic but related to antigens present on WBCs
++
Fever, chills, backache, headache
Apprehension, dyspnea, hypotension, vascular collapse
Disseminated intravascular coagulation (DIC)
Acute kidney injury from acute tubular necrosis
Tachycardia, generalized bleeding, and oliguria in patients under general anesthesia
++
Hemoglobin fails to rise as expected
Acute kidney injury
Acute DIC (low fibrinogen, elevated fibrin degradation products, thrombocytopenia, prolonged prothrombin time)
Hemoglobinemia (plasma pink and hemoglobinuria)
In delayed cases, there is an unexpected drop in hemoglobin and an increase in the total and indirect bilirubins
Offending alloantibody detectable in patient's serum
++
Stop transfusion immediately
Check identification of recipient and blood
Return transfusion product bag with pilot tube to blood bank with fresh sample of recipient's blood for retyping and repeat of cross-match
Hydrate patient vigorously to prevent acute tubular necrosis. Forced diuresis with mannitol may help prevent or minimize acute kidney injury