Use of Bispectral Index Score for Interventional Bronchoscopy Procedures

BACKGROUND Interventional bronchoscopic procedures are novel diagnostic and therapeutic methods in pulmonology, which may be unpleasant and dangerous to the patients; therefore, sedation and in some cases general anaesthesia are recommended. But adjusting the level of sedation is a challenge. In this study we intended to define a range of bispectral index (BIS) score suitable for these procedures. MATERIALS AND METHODS All patients referred to our interventional bronchoscopy unit were enrolled in the study. Sedation was induced using midazolam, sufentanil, and propofol with the patient breathing spontaneously. The target level of sedation was to reach a Ramsay sedation score of 3 and patient tolerance in performing the procedure. The BIS score was recorded at baseline and every five minutes thereafter. Correlation between different BIS values, propofol dosage, duration of procedure, and awakening time was evaluated. RESULTS A total of 70 patients were enrolled in this study with a mean age of 50± 16 years and 34 (48.6%) of them were males. The mean baseline BIS was 96±3.7, and the mean time to reach "stable BIS" ("stable time") was 7.9±6 minutes. The mean "stable BIS" was 52±13.5 and 70% of patients had stable BIS between 40 and 60. CONCLUSION BIS is a useful objective tool for evaluation of sedation, which can guide us through bronchoscopy and related procedures. According to our observational study, reaching the mean BIS level of 52±13.5 is required to prevent complications and ensure feasibility of the procedure.