Evaluation of Oral Simethicone With Low Volume Polyethylene Glycol Bowel Preparation During Colonoscopy

Overview

An adequate bowel preparation has been well established to lead to a successful colonoscopy. Research has consistently demonstrated inadequate bowel preparation with lower adenoma detection rates. Over the years, endoscopy centers have changed the constituents of bowel preparation in light of new research. In 2006, 3 medical organizations recommended the use of polyethylene glycol (PEG) solution for bowel preparation. Initially, a 4 liter PEG solution was commonly used using a split dose regimen for bowel prep. However, many patients found that this large volume gave them side effects including bloating and cramping. Other studies showed that a low volume PEG solution with oral bisacodyl fared equally in terms of adequacy of bowel preparation. With the institution of lower volume PEG preparation our offices noted improved patient toleration, satisfaction, and clinical outcomes. However, multiple endoscopists have noticed an increased in intraluminal bubbles and foam with the low volume preparation. This can impair proper visualization of the bowel wall even with an adequate bowel preparation. The current standard of practice includes irrigation, lavage, and suctioning using a simethicone infused saline during the colonoscopy. Its property of reducing surface tension to help dissolve bubbles and clear the field of view is vital during the procedure. Furthermore, it does not dissolve into the blood stream and thereby, is considered rather safe. This study evaluates whether the addition of oral simethicone with the colonoscopy bowel preparation reduces bubbles and foam during the procedure using a randomized and controlled interventional study.

This prospective, multi-center, randomized, controlled, double (patient and endoscopist) blinded study is conducted at the Gastroenterology Consultants outpatient clinics and endoscopy centers in association with the University of Nevada-Reno School of Medicine. After obtaining signed informed consent, outpatients are recruited and randomized into 1 of 2 treatment groups; PEG3350-Bisacodyl with 200 mg liquid simethicone treatment and PEG3350-Bisacodyl treatment with inert placebo (water). The primary outcome includes reduction of bubbles using the intraluminal bubbles scale. Secondary outcomes include the evaluations of the numbers and types of polyps, numbers and types of masses detected, cecal insertion time, withdrawal time, adverse effects, and the adequacy of bowel prep using the Boston Bowel Prep scale.