Premedication with reformulated simethicone and sodium bicarbonate improves mucosal visibility during upper gastrointestinal endoscopy: a double-blind, multicenter, randomized controlled trial

BACKGROUND: The reformulated simethicone emulsion from Berlin Chemical AG might develop white flocculate precipitate covering the gastric mucosa when used before esophagogastroduodenoscopy (EGD). We aim to investigate whether combining the reformulated simethicone emulsion with 5% sodium bicarbonate solution could prevent the development of white precipitate and improve visibility during EGD. METHODS: Our clinical study involved 523 patients. They were randomly assigned to two groups. In Group A, patients received a warm solution containing 30 ml 5% sodium bicarbonate solution and 15 ml reformulated simethicone emulsion. In Group B, patients received 45 ml 40 °C lukewarm water. Visibility scores were recorded and analyzed. Flushes, volume of flush water, overall time taken for EGD and complications during or after the procedure were also recorded. RESULTS: We found that no white precipitate was observed during EGD in Group A. Moreover, visibility scores in Group A were significantly lower (P < 0.01). Patients in Group A had fewer flushes (P < 0.01) and smaller volume of flush water (P < 0.01). In addition, the overall time taken for the EGD procedure was significantly shorter in Group A (P < 0.01). The percentage of patients who had no adverse response was significantly higher in Group A than in Group B (P < 0.01). CONCLUSIONS: Premedication with a mixed solution of 15 ml reformulated simethicone emulsion and 30 ml 5% sodium bicarbonate solution can prevent the development of white precipitate, substantially enhancing mucosal visibility safely. Trial registration: The registered name of the trial is “Efficacy of using premedication with reformulated simethicone emulsion during upper gastrointestinal endoscopy examination”. Its Current Controlled Trials number is ChiCTR1900021689. Its date of registration is 11 September 2019. Retrospectively registered, http://www.medresman.org.cn/uc/sindex.aspx. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12876-021-01623-w.