Efficacy of bispectral index monitoring as an adjunct to propofol deep sedation for ERCP: a randomized controlled trial

Background and study aims: We sought to determine whether bispectral index (BIS) monitoring is a useful adjunct to the administration of propofol titrated to deep sedation, as measured by reductions of doses of propofol administered during endoscopic retrograde cholangiopancreatography (ERCP). Patients and methods: 90 consecutive patients undergoing ERCP were randomized to receive propofol titrated to deep sedation, with the BIS value either visible (BIS group, n = 46) or invisible (control group, n = 44) to the anesthesiologist. In the BIS group, the anesthesiologist was instructed to use the BIS value as the primary end point for titration of sedation, and to target BIS values between 40 and 60. For the control group, the anesthesiologist was instructed to titrate propofol according to routine practice in the unit using the modified Observer's Assessment of Alertness/Sedation (MOAA/S) Scale (MOAA/S score 0). Results: The mean (SD) propofol doses (mg/min per kg weight) were 0.139 (0.02) and 0.193 (0.02) for the BIS and control groups, respectively (P < 0.001). Mean (SD) BIS values throughout the procedure were 61.68 (7.5) and 56.93 (4.77) for the BIS and control groups, respectively (P = 0.001). During the maintenance phase of sedation (MOAA/S score 0), the mean (SD) BIS values were 53.73 (8.67) and 45.65 (4.39) for the BIS and control groups, respectively (P < 0.001). Conclusions: Our data suggest that BIS monitoring led to a reduction in the mean propofol dose when the BIS value was used as the primary target for sedation in ERCP procedures.