Clearing the Way: Impact of a combined low volume polyethylene glycol lavage with low residue diet and preprocedure simethicone on bowel cleansing quality – a randomised controlled trial

Aims The quality of bowel cleansing is known to influence the quality of colonoscopy. A case has been made for dietary modification in the form of low residue diet (LRD) along with polyethylene glycol (PEG) preparation resulting in better bowel cleansing. Also, combined use of simethicone and PEG as lavage solution for bowel preparation has been shown to reduce abdominal pain, bloating and discomfort. We aimed to assess the safety and efficacy of a combined bowel preparation with low volume PEG, low residue diet and simethicone and compare it to the traditional PEG based bowel preparation regimens.

Methods Patients who attended our department of gastroenterology over a period of 1 year and who underwent colonoscopy for routine clinical indications were randomised into 3 arms in a ratio of 1:1:1 according to the bowel preparation that they received – 1) 4L PEG with clear liquid diet 2) 2L PEG with LRD 3) 2L PEG with LRD with simethicone solution. A computer-generated randomization chart was used to determine allocation. Written instruction on how to prepare and ingest the bowel preparation solution as well as specific dietary advices depending on the allocated study arm was explained at the time of scheduling the exam by trained paramedical staff. All colonoscopies were performed by trained endoscopists (>275 colonoscopies) who were blinded to the preparation received by the patient. The primary outcome was quality of bowel preparation measured by the Boston Bowel Preparation Score (BBPS) and Bubble score. Colonoscopy quality indicators like cecal intubation time and overall procedure duration were recorded. Overall patient satisfaction was assesed using the a 5 point Likert scale. Adverse events like abdominal pain, vomiting, nausea and headache during the course of taking the bowel preparation regimen was also noted.

Results 353 patients were included for the final analysis (4L PEG group – 120, 2LPEG with LRD – 117, 2L PEG with LRD with simethicone – 116). The cleansing quality was not significantly different between the groups (p=0.224). However, the bubble score was significantly better in patients in the simethicone arm (p=0.013). On evaluation of colonoscopy quality metrics, overall duration of the procedure (p=0.016) as well as cecal intubation time (p=0.004) was lower in the simethicone arm.Overall patient satisfaction was better in the simethicone arm although the difference was stastically non-significant (p=0.102). Adverse events like nausea/vomiting (p=0.024), abdominal cramps (p=<0.001) and headache (p=0.002) were reported less frequently in the simethicone arm.

Conclusions Combined use of PEG with low residue diet and simethicone offers advantages in terms of lower overall procedure duration time, cecal intubation time, fewer adverse events and better overall patient satisfaction. However, there was no significant difference in terms of bowel cleansing efficacy.

 

MissingLinkText

Conflicts of interest

Authors do not have any conflict of interest to disclose.

Publication History

Article published online:
15 April 2024