Clinical Trials Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 6, 2019; 7(1): 39-48
Published online Jan 6, 2019. doi: 10.12998/wjcc.v7.i1.39
Efficacy of 0.5-L vs 1-L polyethylene glycol containing ascorbic acid as additional colon cleansing methods for inadequate bowel preparation as expected by last stool examination before colonoscopy
Joon Hyun Cho, Eun Joo Goo, Kyeong Ok Kim, Si Hyung Lee, Byung Ik Jang, Tae Nyeun Kim
Joon Hyun Cho, Eun Joo Goo, Kyeong Ok Kim, Si Hyung Lee, Byung Ik Jang, Tae Nyeun Kim, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Yeungnam University College of Medicine, Daegu 42415, South Korea
Author contributions: Kim TN and Kim KO designed the research; Kim TN, Jang BI, Lee SH, Kim KO, and Goo EJ performed the research; Goo EJ and Cho JH analyzed the data; Kim TN and Cho JH wrote the paper; Kim TN and Cho JH revised the manuscript.
Institutional review board statement: The study was performed in accordance with the Helsinki Declaration and the protocol and informed consent form used were approved beforehand by the Institutional Review Board of Yeungnam University Hospital (IRB No. 2016-03-019).
Informed consent statement: All patients provided written informed consent.
Conflict-of-interest statement: The authors declare no conflicts of interest regarding this manuscript.
Data sharing statement: There are no additional data available for this study.
CONSORT 2010 statement: The authors have read the CONSORT 2010 Statement, and the manuscript was prepared and revised according to the CONSORT 2010 Statement.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Tae Nyeun Kim, MD, PhD, Professor, Division of Gastroenterology and Hepatology, Department of Internal Medicine, Yeungnam University College of Medicine, 170 Hyeonchung-ro, Nam-gu, Daegu 42415, South Korea. tnkim@yu.ac.kr
Telephone: +82-53-6203842 Fax: +82-53-6548386
Received: September 21, 2018
Peer-review started: September 21, 2018
First decision: November 2, 2018
Revised: November 19, 2018
Accepted: November 23, 2018
Article in press: November 24, 2018
Published online: January 6, 2019
Abstract
BACKGROUND

No consensus has been reached in patients suspected of having inadequate bowel preparation regarding optimal salvage methods, which negatively affects the efficacy and quality of colonoscopy. The most ideal and reasonable rescue option involves early suspicion and identification of patients with inadequate preparation before sedation, additional oral ingestion of a suitable preparation formulation, and same-day colonoscopy.

AIM

To compare 0.5-L and 1-L polyethylene glycol containing ascorbic acid (PEG + Asc) as additional bowel cleansing methods after a 2-L split-dose PEG + Asc regimen in patients with expected inadequate bowel preparation before colonoscopy.

METHODS

Individuals with expected inadequate bowel preparation based on last stool form, such as turbid liquid, particulate liquid, or liquid with small amounts of feces, were randomized to either a 0.5-L PEG + Asc group or a 1-L PEG + Asc group. The primary endpoint was bowel preparation as assessed using the Aronchick bowel preparation scale (ABPS) and Boston bowel preparation scale (BBPS) scores. The secondary endpoints were cecal intubation time, withdrawal time, polyp detection rate (PDR), adenoma detection rate (ADR), individual compliance with additional PEG + Asc, and patient satisfaction.

RESULTS

Initially, 98 patients were included, but 8 were later excluded due to withdrawal of consent to participate in the study. Adequate bowel preparation (as assessed by ABPS) was observed in 80.9% (38/47) of subjects in the 0.5-L group and in 88.4% (38/43) of subjects in the 1-L group (P = 0.617). Mean total BBPS was 6.7 points in the 0.5-L group and 7.0 points in the 1-L group (P = 0.458). ADRs and PDRs were similar in the two groups, and cecal intubation and withdrawal times were not significantly different. However, mean patient satisfaction score was significantly higher in the 0.5-L group (P = 0.041).

CONCLUSION

The bowel cleaning efficacy of additional 0.5-L PEG + Asc was not inferior to that of 1-L PEG + Asc. Additional 0.5-L PEG + Asc is worthwhile when inadequate bowel preparation is expected before colonoscopy.

Keywords: Inadequate bowel preparation, Additional colon cleansing, Colonoscopy, Polyethylene glycol

Core tip: The most reasonable rescue option in patients with inadequate bowel preparation is early suspicion and identification of patients with inadequate preparation before sedation, additional oral ingestion of a suitable preparation, and same-day colonoscopy. This is the first prospective randomized clinical trial to compare the effects of two additional polyethylene glycol (PEG) containing ascorbic acid (PEG + Asc) doses. The study shows that the bowel cleansing efficacy of an additional 0.5-L PEG + Asc was not inferior to that of an additional 1-L PEG + Asc when administered prior to colonoscopy in patients with suspected inadequate bowel preparation. Thus, the additional 0.5-L PEG + Asc regimen appears to be sufficient when inadequate bowel preparation is expected before initiating colonoscopy, based on considerations of bowel cleansing efficacy and patient satisfaction.