ABSTRACT
Objective?To compare the effect of chymotrypsin, N-acetylcysteine and chain protease on the image visibility before upper gastrointestinal endoscopy.?Methods?The patients who underwent painless gastroscopy from January 2016 to July 2016 were divided into four groups before gastroscopy. Group A is the control group (simethicone 600 mg + NaHCO3 2 g). Group B is the chymotrypsin group (simethicone 600 mg + chymotrypsin 200 u + NaHCO3 2 g). Group C is the N-acetylcysteine group (simethicone 600 mg + N-acetylcysteine 600 mg+ NaHCO3 2 g). Group D is the chain protease group (simethicone 600 mg + chain protease 20 000 u + NaHCO3 2 g). The corresponding drug is diluted in 100 ml of normal saline. Each group of patients was required to oral the diluted solution 30 minutes before gastroscopy. All patients’ gastroscopies were completed by one endoscopist, and each patient’s endoscopic image visibility were evaluated by the other two endoscopists. The three endoscopists were unaware of grouping. Each group chose 54 patients diagnosed with chronic gastritis to conduct a retrospective study. The total patients were 216. The total scores of image visibility, the washing time and the incidence of complications were compared and analyzed.?Results?The total image scores of group A, B, C and D were (32.19 ± 3.06), (36.64 ± 3.18), (39.03 ± 3.69) and (39.89 ± 3.35), respectively. Group A was the lowest (P < 0.05), followed by group B (P < 0.05). The total scores of group C and D were higher, and there was no difference between groups (P > 0.05). The washing time of each group were (42.00 ± 21.67) s, (17.78 ± 13.39) s, (12.32 ± 11.08) s and (11.98 ± 10.04) s. Group A was the longest (P < 0.05), while there were no significant differences among group B, C and D (P > 0.05). There were no significant differences in adverse effects among groups after upper gastrointestinal endoscopy.?Conclusion?Before conducting upper gastrointestinal endoscopy, simethicone in combination with chymotrypsin, N-acetylcysteine and chain protease can safely and effectively improve the visibility of endoscopic images and shorten the washing time. There is no obvious adverse reactions. N-acetylcysteine group and the chain protease group have the best effect, and the two effects are similar. So simethicone in combination with N-acetylcysteine or chain protease can be more effective in enhancing gastroscopic image visibility, shorter washing time, which can improve the detection rate of early lesions. When the clinical use of N-acetylcysteine and chain protease is limited, the use of chymotrypsin can also be considered to improve the visibility of endoscopic images.