Abstract: 　Objective To evaluate the safety and clinical value of painless colonoscopy in children and the feasibility of colonoscopic polypectomy. Methods　We retrospectively analyzed the results of 473 cases of painless colonoscopy in Jiangxi provincial Children's Hospital, from July 2017 to July 2019. The patients were divided into four groups as infancy (<3 years), preschool-age (3-6 years), school-age (6 -11 years) and adolescence (12-16 years). The safety of painless colonoscopy, the caecal intubation rate, the detection of intestinal lesions and the feasibility of colonoscopic polypectomy were analyzed. Results　The 473 patients had accepted painless colonoscopy for 487 times, including 59 infancy cases, 247 preschool-age cases, 121 schoolage cases and 46 adolescence cases. The colonoscopy records showed that 313 cases were detected to have intestinal lesions including intestinal polyp (n = 259), chronic colitis (n = 32), Crohn’s disease (n = 7), and ulcerative colitis (n = 3). There were significant differences in the overall ratios of polyps, chronic colitis, Crohn's disease and ulcerative colitis in children among different age groups (χ2 = 44.094, P <0.001). The peak age of polyps was in preschool-age, chronic colitis and Crohn's disease occurred mostly in school-age and adolescence, and ulcerative colitis was more common in adolescence. The caecal intubation rate was 85.6% (417/487). There were no serious complications such as respiratory arrest or sudden cardiac arrest during the operation, and two cases had post-anesthetic shivering after operation. With high frequency electrosurgical coagulation, 259 cases of intestinal polyps were treated with painless colonoscopic polypectomy, three cases had intraoperative intestinal bleeding, 2 cases had postoperative intestinal bleeding, and two cases had perforation after operation. Conclusion　Painless colonoscopy in children is a safe and effective method for the diagnosis of lower gastrointestinal diseases. Distribution of lower gastrointestinal diseases is different in children among different age groups. The high frequency electrosurgical coagulation resection under painless colonoscopy is a feasible treatment for intestinal polyps in children.

Key words: painless colonoscopy;　polypectomy;　child