To explore the optimal scheme of bowel preparation for patients undergoing painless gastroscopy combined with colonoscopy, so as to provide a new strategy for improving the quality of bowel preparation and detection rate of colon lesions under colonoscopy.

From September 2016 to May 2017, 120 healthy people who underwent combined painless gastrointestinal endoscopy in the Second Affiliated Hospital of Xi'an Jiaotong University were selected as the research objects. They were randomly divided into observation group and control group. The two groups were given laxatives regularly, while the observation group was given total decontamination drug (Mosapride). The operation time of colonoscopy, ileum intubation rate, colon cleanliness (Boston score), detection rate of colonic polyps and other diseases were compared between the two groups. At the same time, the above observation indexes in the same group of people with different medication time were compared.

The operation time of colonoscopy in the observation group was significantly shorter than that in the control group (11.6±2.8 min vs. 16.4±3.2 min, t=6.26; P＜0.05). In terms of colon cleanliness, 83.3% of the observation group and 53.3% of the control group had good bowel preparation (χ²=4.38, P<0.05). Among the subgroups taking the medication time as the observation object, in observation groups, there were no significant difference in the intestinal preparation rate between taking medicine 10 h before examination and taking medicine 12 h and 8 h before examination (χ²=3.120, P=0.210), but the intestinal preparation rate of the people taking medicine 10 h before examination was the highest (95%); In control groups, the intestinal preparation rates of taking medicine 8, 10 and 12 hours before examination were different (χ²=8.973, P=0.011), among them, the intestinal preparation rate of the people taking medicine 10 hours before examination was the highest, which was 80%, and the difference between the two groups (10 h vs 12 h) was statistically significant (χ²=8.286, P=0.004). There was no significant difference in ileum intubation rate between the two groups (100% and 98.3%, respectively). The detection rate of colonic polyps and other diseases in the observation group was significantly higher than that in the control group (46.7% vs. 18.3%, χ²=3.90; P＜0.05).

The addition of total gastrointestinal motility drugs is helpful to improve the intestinal cleanliness and the detection rate of intestinal lesions in patients undergoing painless gastroscopy combined with colonoscopy. The patients who take cathartic 10 hours before examination may get better intestinal cleanliness.