Even with the great progress in blood safety, such as the nucleic acid amplification test(NAT) for HBV, HCV and HIV, ABO-mismatched transfusion still occurs in the 21st century. Computer crossmatch between the patient's blood type already registered on computer, the patient's blood type as examined just before transfusion and the blood type labeled on blood bags all help avoid misunderstanding of blood type at shipping. Computerized management of the transfusion services database is also effective in promoting appropriate transfusion or autologous transfusion.
Since mistakes can occur anywhere in the system, the Japanese Society of Blood Transfusion(JSBT) made a poster showing six steps where errors were most likely. They then distributed a questionnaire about mismatched transfusion to 777 major hospitals and made it clear that the main cause of mistakes was confirmation errors at bedside before transfusion. In response to the findings, JSBT created a manual for performing exactly matched and safe transfusions, including a manual for transfusion in emergencies, as well as first-line treatment procedures in case of major mismatched transfusion.
In order to avoid mistakes at bedside, a barcode matching system between the patient's wristband and blood bag is ideal. It will also be useful for comprehensive risk management in modern medicine.

*Department of Transfusion Medicine & Immunohematology, Toranomon Hospital, Minato-ku, Tokyo 105-8470