The Predictive Factors On Inadequate Bowel Preparation And Some Randomized Trial To Improving Bowel Preparation For Colonoscopy

Section 1 Constipation, fiber intake and non-compliance contribute to inadequate colonoscopy bowel preparation: a prospective cohort studyBackground: Adequate bowel preparation is vital to colonoscopy. Current evidence on bowel preparation has largely emanated from western countries. We sought to identify risk factors for inadequate bowel preparation for colonoscopy in the Chinese population.Methods: Patients who had indications for colonoscopy in the out-patient department between March 2013 and December 2014 were prospectively enrolled. Questionnaires were administered to the patients. Demographic, clinical characteristics and procedure-related parameters such as procedure time were recorded. Bowel preparation was assessed using Boston bowel preparation scale(BBPS) score.Results: A total of 409 patients(mean age: 48.8 ± 12.9 years) of whom 61% were male participated in the study. On univariate analysis, poor educational status(P = 0.020), chronic constipation(P = 0.001), no physical exercises after medication(P < 0.001), high fiber diet during the 24 h period immediately preceding colonoscopy(P < 0.001), incomplete intake of the preparation(P < 0.001), passage of yellow or dark stools before colonoscopy(P < 0.001), waiting time(P = 0.001) and stool frequency after medication(P = 0.048) were associated with inadequate bowel preparation. On multivariate logistic regression analysis, chronic constipation(Odds Ratio [OR] 2.05; 95% Confidence Interval [CI], 1.31-3.23), incomplete intake of the preparation(OR 2.77; 95% CI, 1.47-5.21) and high fiber diet(OR 2.15; 95% CI, 1.40-3.28) were independent risk factors for inadequate bowel preparation.Conclusion: Chronic constipation, poor compliance with treatment and high fiber diet predict poor bowel preparation. Patients with these risk factors require a more effective strategy for bowel preparation.Section 2 Gum chewing cannot improve the quality of bowel preparation for colonoscopy: an endoscopist-blinded, randomized controlled trialBackground: Gum chewing can accelerate the gastrointestinal tract motility; clinical studies suggested gum chewing can reduce postoperative ileus. However, there was no trial investigated the effect of gum chewing on bowel preparation for colonoscopy in addition to polyethylene glycol(PEG). The objective of this study was to investigate whether gum chewing before colonoscopy can increase the quality of bowel preparation.Methods: It was a single center, prospective, randomized, controlled trial. Consecutive patients undergoing colonoscopy were randomized to gum group or control group. Patients in gum group chewed sugar-free gum every 2 hours for 20 minutes each time from the end of drinking 2L polyethylene glycol(PEG) to the beginning of colonoscopy. Patients in control group only received 2L PEG before colonoscopy. The quality of bowel preparation, procedure time, adenoma detection rate, patients’ tolerance, and adverse events was compared.Results: 300 patients were included in the study(150 in the control group, 150 in the gum group). More than 90% of patients in both groups were satisfied with the process of bowel preparation, and the incidence of adverse events was comparable in the two groups(42.0% vs. 46.0%, p = 0.49). The mean Boston Bowel Preparation Scale(BBPS) score was 6.2 ± 1.4 and 6.1 ± 1.2 in control group and gum group, respectively, and the difference between the two groups was not significant(P = 0.51).Conclusions: This study indicate that though patients with gum chewing are more likely satisfied with the process of bowel preparation and to repeat colonoscopy in the future, it cannot improve the quality of bowel preparation for colonoscopy. Clinical Trials.gov number, NCT02507037.Section 3 Efficacy of simethicone as premedication in improving visibility during colonoscopy.Background: colonoscopy is considered as the gold standard tool to investigate colon and rectum and the most effective method for assessing colonic lesions. Colonic bubbles associated with polyethylene glycol-electrolyte solution(PEG-ELS) are common and obscure mucosal visualization. The objective of this study was to investigate whether is efficacy of simethicone as premedication in improving visibility during colonoscopy.Methods: It was a multi-center, prospective, randomized, controlled trial. Consecutive patients undergoing colonoscopy were randomized to simethicone group or control group. Bubble severity for colonic segments was assessed on withdrawal as Grade 0 = No or minimal scattered bubbles; Grade 1 = Bubbles covering at least half the luminal diameter; Grade 2 = Bubbles covering the circumference of the lumen; Grade 3 = Bubbles filling the entire lumen, incidence and severity of side effects, and polyp detection. Patients in simethicone group: 2 hours of 2L polyethylene glycol electrolyte + simethicone(30 ml) mixed solution. Patients in control group only received 2L PEG before colonoscopy. Evaluation and comparison of two groups of patients with polyps detection rate, time to reach the caecum, withdrawal time, remove the bubble rate, safety, etc.Results: 272 patients were included in the study(144 in the control group, 128 in the simethicone group). Two groups of patients with gender(male/ woman 167/61 vs72/72 p=0.700)、age(49.33±11.0 vs 50.58±11.12 p=0.192)、BMI(23.01±3.19 vs 23.28±3.38 p=0.347)、Insert time(7.75±3.95 vs7.80±3.76 p=0.602)、Polyp detection rate(26.6% vs 32.6% p=0.274) are no significant differences, withdrawal time(6.56±1.83 vs 7.18±2.14 p=0.003), The bowel remove rate(p< 0.001)、Boston Bowel Preparation Scale(BBPS) score(< 0.001) are significant differences,Conclusions: Bowel preparation before colonoscopy for simethicone can shorten the operation time, reduce intestinal bubble production, improve the colonic mucosa of clarity, but failed to improve colon polyps detection rate.Clinical Trials.gov number:NCT02540239.