Prospective Randomized Trial of Bispectral Index Monitoring of Sedation Depth during Flexible Bronchoscopy

Abstract

Background: The clinical benefits associated with the use of the bispectral index (BIS) to monitor the depth of sedation during flexible fiberoptic bronchoscopy (FFB) are questionable. Objectives: To evaluate the added value in terms of procedural safety and patients' awareness of monitoring sedation depth using the BIS compared to conventional clinical judgment alone in patients undergoing FFB under propofol sedation. Methods: The cohort included 81 patients undergoing diagnostic or therapeutic bronchoscopy under propofol sedation that were prospectively randomized to guide the depth of sedation by BIS monitoring (BIS group; n = 40) or conventional monitoring (control group; n = 41). Results: The mean durations of the procedure were 18 and 19 min in the BIS and control groups, respectively. No significant difference was noted in the dosage of propofol used between the BIS and control groups (168.7 vs. 167.3 mg, respectively). Average sedation-related oxygen saturation drop and transcutaneous CO₂ rise were not significantly different between groups. There was also no significant difference in the percentage of patients that required either hemodynamic support (5 vs. 7.5%, respectively), oxygen supplementation by 100% O₂ mask (67.5 vs. 82.5%, respectively) or Ambu face mask manual ventilation (2.5 vs. 5%, respectively) between the groups. No significant difference was noted in terms of patients' awareness during the procedure, which was assessed following recovery by a structured Brice interview. Conclusion: Using BIS to guide the depth of sedation during propofol sedation in patients undergoing FFB of relatively short duration offers no clinically significant advantages over conventional monitoring.