[Present status of critical hemorrhage and its management in the operating room].

Hemorrhage is a major cause of cardiac arrest in the operating room. Many human factors, including surgical procedures, transfusion practices, blood supply, and anesthetic management, are involved in the process that leads to hemorrhage developing into a critical situation. It is desirable for hospital transfusion committees to prepare hospital-based regulations on 'actions to be taken to manage critical hemorrhage', and practice the implementation of these regulations with simulated drills. If intraoperative hemorrhage may become critical, a state of emergency should immediately be declared to the operating room staff, the blood transfusion service staff, and blood bank staff in order to organize a systematic approach to the ongoing problem and keep all responsible staff working outside the operating room informed of events developing in the room. To rapidly deal with critical hemorrhage, not only cooperation between anesthesiologists and surgeons but also linkage of operating rooms with blood transfusion services and a blood bank are important. When time is short, cross-matching tests are omitted, and ABO-identical red blood cells are used. When supplies of ABO-identical red blood cells are not available, ABO-compatible, non-identical red blood cells are used. Because a systematic, not individual, approach is required to prevent and manage critical hemorrhage, whether or not a hospital can establish a procedure to deal with it depends on the overall capability of critical and crisis management of the hospital. (Review).