Administration of maximum dose of mucolytic solution before upper endoscopy - a double-blind, randomized trial.

Objective: The aim of the study was to demonstrate that an administration of mucolytic solution with a maximum dose of simethicone and n -acetylcysteine before upper endoscopy improves mucosal visibility compared to a group without administration of mucolytic solution or water.

Methods: This study was a double-blind, randomized controlled trial. Patients were randomized into four groups, with the administration of 100 ml of water + 600 mg n -acetylcysteine + 400 mg simethicone, 100 ml of water + 400 mg n -acetylcysteine + 20 mg simethicone, 100 ml of water, and without any water or mucolytic solution. During the examination, a total of 10 images were taken in the defined areas. The overall visibility score was given by the sum of the 0-5 scores of the five areas and was assessed by the endoscopist performing the procedure and the blinded endoscopists using static images.

Results: A total of 129 patients were randomized. The group of patients did not differ in age, sex distribution, and indications significantly. The overall visibility score as assessed by the endoscopist performing the procedure was significantly higher in the group with the maximum dose of mucolytic solution compared to the group without solution or water (18.9 ± 2.9 vs. 16.6 ± 3.3, P  = 0.023). This difference was not evident by the blinded evaluation of static photographs.

Conclusion: Administration of mucolytic solution with a maximum dose of n -acetylcysteine and simethicone before upper endoscopy improved mucosal visibility in the upper gastrointestinal tract compared with the group without any preparation while evaluated by performing endoscopist.