Bispectral index monitoring of sedation depth during endoscopy: a meta-analysis with trial sequential analysis of randomized controlled trials

INTRODUCTION. The Bispectral Index (BIS) provides an objective measure of the level of sedation and general anesthesia. We performed this meta-analysis and trial sequential analysis (TSA) of randomized clinical trials to clarify whether BIS monitoring is helpful in enhancing intraprocedual safety, shortening procedure duration or promoting recovery during sedation for endoscopic procedures. EVIDENCE ACQUISITION. PubMed, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials [CENTRAL]) databases, reference lists of articles as well as relevant articles from "Google Scholar" were searched until May 31st, 2018. Randomized controlled trials (RCTs) comparing BIS with clinical signs for titration of sedation depth during endoscopy were screened and identified if they reported one of the following outcome measures: intraprocedual safety (hemodynamic stability and cardiorespiratory complications such as hypoxia, hypertension/hypotension, and bradycardia/tachycardia), procedure duration, recovery time and patient/endoscopist's satisfaction. EVIDENCE SYNTHESIS. Twelve studies with 13 RCTs recruiting 1372 patients were identified with great inter-trial heterogeneity. Meta-analysis found that BIS monitoring of sedation depth was associated with lower incidences of intraprocedural hypoxia (P=0.009) compared with clinical signs which was not confirmed by TSA. Meta-analysis and TSA found that the endoscopic procedure duration (P=0.143), recovery time (P=0.083), satisfaction scores from both the cases (P=0.085) and endoscopists (P=0.125) and the incidences of hypertension/hypotension (P=0.639) or heart rates (P=0.201) were similar between BIS and control group. CONCLUSIONS. More high-quality large-sampled RCTs are needed to confirm whether BIS monitoring for endoscopy sedation helps reduce intraprocedural hypoxia. BIS monitoring fails to shorten procedure duration, promote recovery or boost satisfaction among patients and endoscopists.