Premedication in upper gastrointestinal endoscopy to improve mucosal visualization. A systematic review.

Objective: This review aims to evaluate the efficacy and safety of premedication comprising mucolytics and/or defoaming agents to improve the quality of visualization during elective upper digestive endoscopy (elective upper GI endoscopy) procedure.

Materials and methods: A systematic review of the literature contained in electronic databases (Medline/Pubmed, Embase, and Lilacs) was performed to identify randomized controlled trials and systematic reviews that assessed patients undergoing upper gastrointestinal endoscopy (elective upper GI Endoscopy) under sedation, after being premedicated with mucolytics and/or defoaming agents for mucous clearance. A meta-analysis was conducted to determine the relative efficacy and safety profile of such premedication.

Results: In patients undergoing an elective procedure, premedication with defoaming and/or mucolytic agents improved the visibility score of the gastric antrum during upper GI endoscopy. The use of combined agents such as simethicone vs. water and N-acetyl cysteine (NAC) vs. water showed significant differences in favor of the active substance; however, no significant differences were found between the use of simethicone alone vs. simethicone + NAC. The use of pronase and dimethylpolysiloxane, among others, produced no significant difference (additive effect) in the visualization score. This is associated with the limited number of studies that performed similar comparisons and the heterogeneity of the outcomes. No major adverse effects were reported in the studies that were included regarding safety outcomes (i.e., volume of fluids required for clearance, risk of bronchoaspiration, and disinfection of equipment).

Conclusions: The results of this review evidence that premedication with simethicone (a drug registered in Colombia for use against functional gastrointestinal disorders; ATC group A03A) is safe and effective for improving the quality of visualization during elective upper GI endoscopy procedures. However, no significant differences were observed in the visualization quality with the use or addition of other agents. The use simethicone should be set as off-label use and should be implemented at the prescriber's discretion. The use of simethicone as a premedication is recommended to improve the endoscopic visualization score in elective procedures.