Experience with the medical event reporting system for transfusion medicine (MERS-TM) at three hospitals

Background: The MERS-TM assists hospital transfusion services to identify, analyze, and correct system events relating to the delivery of blood to patients. Methods: The MERS-TM system was used from February of 1999 to December 2002. All reported near-miss and actual events were recorded and analyzed. Results: During these 47 months, 4670 events were reported by the transfusion service. Of these events, 94% were classified as a near-miss event and 93% were detected before the blood product was administered. No ABO-incompatible transfusions were detected despite transfusion of 50,137 units of red blood cells. High severity events with the potential for patient harm accounted for 241 (5%) of the 4670 events. Nursing related events accounted for 188 (78%) of the high severity events. In one out of 4430 (0.023%) samples tested, a high severity sample-testing event was detected. In one out of 1550 (0.06%) samples collected, a high severity sample-collection event was detected. Conclusion: An event reporting system is essential if one is to determine where and how often events are occurring within the transfusion process.