Analysis of ABO discrepancies occurring in 35 French hospitals

BACKGROUND: The risk of immunohemolytic reaction owing to ABO-mismatched mistransfusion is 100 to 1000 times higher than the risk of viral infection. Like analysis of incident reports, evaluation of near-miss events can provide useful insight into hazardous situations for mis-matched blood transfusion. The aim of this prospective study was to assess the incidence and root causes of all ABO discrepancies, detected by a central hematology laboratory, in blood samples referred from 35 district hospitals. STUDY DESIGN AND METHODS: ABO discrepancies were detected by comparing either two current blood specimens or a current and historical specimen collected over a 5-year study period. Discrepancies were investigated by retyping new samples, checking sample identification, and reviewing previous hospital records. RESULTS: A total of 118 ABO discrepancies were discovered in a series of 407,769 tests carried out during the study period. The incidence of ABO discrepancies was 1 per 3,400. This figure was 10 times higher than the incidence of ABO-mismatched transfusions. Most of these ABO discrepancies were due to phlebotomy errors, that is, collection from wrong patient. The second most common cause involved clerical errors during patient registration or identification. CONCLUSION: ABO discrepancies can result from errors made not only by the medical staff during phlebotomy but also to by the clerical staff during registration and identification. These findings emphasize the need to standardize data transmission between health care personnel.