The Effect of Using Premedication of Simethicone/Pronase With or Without Postural Change on Visualization of the Mucosa Before Endoscopy: A Prospective, Double Blinded, Randomized Controlled Trial.

INTRODUCTION: To investigate the efficacy and safety of preprocedural simethicone (S) and pronase (P) for optimal mucosal visualization during esophagogastroduodenoscopy with sedation. The effect of postural change combined with premedication on mucosal visibility was also examined. METHODS: The study randomized 496 patients into 8 groups based on the type of premedication provided and whether a postural change occurred. The premedication in the control group was 100 mL of normal saline solution (NS). The remaining 3 intervention groups were administered 100 mL of simethicone alone (S), pronase solution alone (P), and simethicone plus pronase solution (S + P). Each group was classified into subgroups according to whether there was a postural change (PC). The mucosal visibility score (MVS), total mucosal visibility score (TVS), procedure time, water consumption for mucosal cleansing, and proportion of patients with diminutive lesions <5 mm were recorded. RESULTS: The P and S groups had a significantly better TVS than the NS group (11.86 ± 3.36 in group P vs 14.52 ± 2.57 in group NS, P < 0.001; 12.36 ± 2.93 in group S vs 14.52 ± 2.57 in group NS, P = 0.006). The TVS was better in the P group than in the S group (11.86 ± 3.36 vs 12.36 ± 2.93, P = 0.037). The MVS was significantly better in the esophagus and duodenum and worse in the upper and lower gastric body in the S group than in the P group. The P + S group had a significantly better TVS than the P and S groups (9.81 ± 2.90 in group P + S vs 11.86 ± 3.36 in group P and 12.36 ± 2.93 in group S, respectively, P < 0.001),\ and had a reduced amount of flushing water during the procedure (0 [interquartile range [IQR]: 0-33] mL in group P + S vs 40 [IQR: 0-70] mL in group P, P < 0.01; 0 [IQR: 0-33] mL in group P + S vs 50 [IQR: 20-98] mL in group S, P < 0.001). The TVS was significantly better in the P + S + PC group than in the P + S group (8.44 ± 2.10 vs 9.81 ± 2.90, P = 0.003). The MVS was significantly better in the gastric antrum, fundus, and upper and lower gastric body in the P + S + PC group than in the P + S group. There was no significant difference in the detection rate of diminutive lesions among the different groups during an endoscopic examination ( P > 0.05). DISCUSSION: The combination of preprocedural administration with simethicone and pronase achieved superior mucosal visualization compared with saline, simethicone, or pronase alone in patients receiving upper endoscopy. Postural change maneuvers performed before endoscopy further improved the mucosal visibility in most parts of the stomach when used with preprocedural simethicone and pronase.