Three large-scale clinical trials conducted in the United States and abroad evaluated more than 30,000 patients to investigate the incidence of awareness with recall and the impact of BIS monitoring on predicting and preventing awareness.
AIM Trial: 19,575 patients were enrolled in this multi-center U.S. study. This study established that awareness with recall occurs in the U.S. at a rate of 1-2 cases per 1,000 patients receiving general anesthesia. Twenty million patients receive general anesthesia in the U.S. each year, suggesting that approximately 100 patients experience awareness with recall each operating weekday. Study findings were consistent with international research evaluating the incidence of awareness. (Anesth Analg. 2004; 99:833-9.)
B-AWARE Trial: 2,503 high awareness-risk patients participated in this clinical trial. Patients evaluated underwent a variety of procedures, including cardiac surgery, trauma surgery, rigid bronchoscopy, and cesarean section. Patients were randomly assigned to receive either standard general anesthesia, or general anesthesia with BIS monitoring. Study findings revealed that BIS-guided anesthesia reduced the incidence of awareness with recall by approximately 82%. (Myles PS, Leslie K. Bispectral Index Monitoring to Prevent Awareness During Anaesthesia: The B-Aware Randomised Controlled Trial. The Lancet 2004; 363: 1757-63.)
SAFE2 Trial: This study was conducted in Sweden and investigated the incidence of awareness in two groups of consecutively-treated patients. 7,826 patients receiving standard general anesthesia were compared with 4,945 patients who received BIS-guided anesthesia. In this study, routine use of BIS monitoring reduced the incidence of awareness in the general patient population by 77% compared to historical control. (Ekman A, Lindholm ML, Lennmarken C, Sandin R. Reduction in the Incidence of Awareness Using BIS Monitoring. Acta Anaesthesiologica Scandinavica 2004; 48 (1): 20-6)
For additional information on any of these studies, click on the links below:
080-0340 1.03