The least incompatible crossmatch red blood cell transfusion by biological compatibility test

Introduction: Pretransfusion testing is an essential serological test to protect the recipient from hemolysis and provide compatible blood product. The final step is the crossmatching test which is done by the transfusion center. Although all products are crossmatched in same cases, compatible products may not be available. Aims and Objectives: This study aimed to determine the safety and efficacy of the least incompatible crossmatched erythrocyte transfusion, through the use of biological in vivo crossmatch testing. Materials and Methods: The study included twenty patients who required transfusion and for whom appropriate red blood cell (RBC) could not be found. Totally, 69 units of least incompatible RBC transfusion from crossmatch incompatible products was administered by applying the "in vivo compatibility" test. Patients were observed during the transfusion with respect to acute hemolytic reactions that could develop. The biochemical hemolysis parameters were examined before and at 24 h after transfusion. Results: All transfusions were completed successfully with no complications or symptoms observed in any case. A statistically significant increase in hematocrit (Hct) and hemoglobin was seen post transfusion (P < 0.001). As parameters of hemolysis, lactate dehydrogenase and bilirubin levels were found to be statistically normal (not increased) (P = 0.453 and 0.946, respectively). Conclusions: Biological in vivo compatibility testing seems to be a safe, predictive, and bedside feasible test, which could be lifesaving for many patients.