Su1532 Evaluation of One-Split and Four-Split Dosing of Hypertonic Polyethylene Glycol Solution and No Split Dosing of Isotonic Polyethylene Glycol Solution for Bowel Cleansing Before Colonoscopy

Su1531 Comparison of Quality of Bowel Preparation Between 4L Polyethylene Glycol and 2L Polyethylene Glycol Plus Ascorbic Acid With and Without Simethicone a Preliminary Report Sun Mi Kang*, Eun Young Kim, Si Hye Kim, Byung Seok Kim, Jimin Han, Jin Tae Jung, Joong Goo Kwon, Chang Hyeong Lee, Ho Gak Kim Department of Internal Medicine, Catholic University of Daegu School of Medicine, Daegu, Korea (the Republic of) Background/Aim: Optimal bowel preparation is essential for the high quality colonoscopic procedure. Polyethylene glycol based solution is the most commonly used bowel preparation agent. This study has investigated the quality of bowl preparation between two preparation regimen with and without supplemetal use of simethicone. Methods: Prospective, single-blind, randomized comparative study was carried out from a single center. Patients were randomly assigned into 4 groups: 4L polyethylene glycol(4L-PEG), 4L PEG with simethicone(4L-PEG+S), 2L polyethylene glycol plus ascorbic acid(2L-PEG-Asc), 2L PEG-Asc with simethicone(2L-PEG-Asc+S). In groups with simethicone, patients took 400mg of simethicone after second split dose of PEG based solution. Boston Bowel Preparation Scale was used to evaluate the quality of bowel preparation. Degree of bubble formation was recorded for three colonic segments (the right side of the colon-including the cecum and ascending colon/ the transverse section of the colon-including the hepatic and splenic flexures/ and the left side of the colon-including the descending colon, sigmoid colon, and rectum) during the withdrawal of colonoscope. Adenoma detection rate (ADR) and polyp detection rate (PDR) were compared between the groups. Tolerability and willingness to repeat colonoscopy with same preparation regimen were also evaluated by using the questionnaire. Results: Overall, 191 patients were enrolled and randomly allocated to the 4 groups. There was no significant difference in the degree of bowel cleansing according to the preparation regimen (Boston Bowel Preparation Scale: 4L-PEG/4L-PEG+S/2L-PEG-Asc/2L-PEG-Asc+S 6.581/6.571/6.54/ 6.98, PZ0.350). Degree of foam and bubble formation was significantly decreased in both simethicone groups (total bubble grade score: 4L-PEG+S/2L-PEG-Asc+S 5.633/ 5.633 vs 4L-PEG/2L-PEG-Asc 4.93/4.98, PZ0.002). In the subgroup analysis, female showed more significant improvement in the bubble score: 4L-PEG+S/2L-PEGAsc+S 5.923/5.733 vs 4L-PEG/2L-PEG-Asc 4.636/5.125, PZ0.000). ADR and PDR were 39%/35%/38%/36% and 56%/54%/53%/52% respectively for 4L-PEG/4L-PEG+S/2LPEG-Asc/2L-PEG-Asc+S. Patients had more satisfaction with 2L PEG-Asc regimen (2LPEG-Asc/2L-PEG-Asc+S 92%/89.8% vs 4L-PEG/4L-PEG+S 74.42%/69.39%, PZ0.007). The patients were more willing to repeat colonoscopy with 2L PEG-Asc (2L-PEG-Asc/ 2L PEG-Asc+S 94%/85.71% vs 4L-PEG/4LPEG+S 62.79%/63.2739%, PZ0.000). Conclusions: Low volume PEG-Asc showed similar effectiveness in bowel preparation compared to large volume PEG. Supplemental use of simethicone decreased the occurrence of foam and bubbles, especially in female. 2L PEG-Asc regimen was better tolerated and patients were willing to repeat colonoscopy with 2L PEG-Asc regimen.