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Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 21, 2023; 29(11): 1685-1707
Published online Mar 21, 2023. doi: 10.3748/wjg.v29.i11.1685
Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature
Endrit Shahini, Emanuele Sinagra, Alessandro Vitello, Rocco Ranaldo, Antonella Contaldo, Antonio Facciorusso, Marcello Maida
Endrit Shahini, Gastroenterology Unit, National Institute of Gastroenterology-IRCCS “Saverio de Bellis”, Castellana Grotte, Bari 70013, Italy
Emanuele Sinagra, Gastroenterology and Endoscopy Unit, Fondazione Istituto G. Giglio, Cefalù 90015, Italy
Alessandro Vitello, Marcello Maida, Gastroenterology and Endoscopy Unit, S.Elia-Raimondi Hospital, Caltanissetta 93100, Italy
Rocco Ranaldo, Department of Internal Medicine, “Mazzolani-Vandini” Hospital, Digestive Endoscopy, Ferrara 744011, Italy
Antonella Contaldo, Gastroenterology Unit, National Institute of Gastroenterology “S de Bellis” Research Hospital, Bari 70013, Italy
Antonio Facciorusso, Department of Medical Sciences, University of Foggia, Section of Gastroenterology, Foggia 71122, Italy
Author contributions: Shahini E and Maida M are the guarantors of the integrity of the entire study, and contributed to the manuscript drafting and revision for important intellectual content; all authors contributed to the manuscript editing and had full control over the preparation of the manuscript.
Conflict-of-interest statement: All authors have no proprietary, financial, professional, or other personal interest of any nature or kind in any product, service, and/or company that could be construed as influencing the position presented in, or the review of this manuscript.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Endrit Shahini, MD, National Institute of Gastroenterology-IRCCS “Saverio de Bellis”, Castellana Grotte, Bari 70013, Italy. endrit.shahini@irccsdebellis.it
Received: December 1, 2022
Peer-review started: December 1, 2022
First decision: February 1, 2023
Revised: February 2, 2023
Accepted: March 7, 2023
Article in press: March 7, 2023
Published online: March 21, 2023
Abstract

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

Keywords: Colorectal cancer, Colonoscopy, Adenoma detection rate, Bowel preparation, Polyethylene glycol

Core Tip: Almost a quarter of procedures are still performed with inadequate preparation. A strategy that includes a low-fiber diet for an extended period of time, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may improve cleansing success rates in the elderly. In addition, while no specific product is recommended for difficult-to-prepare patients, clinical evidence suggests that 1-L polyethylene glycol (PEG) plus ascorbic acid preparation is associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Isotonic high volume PEG solutions should be given to patients with severe renal failure.