Introduction Bowel preparation for colonoscopy should be effective at bowel cleansing, have a low side-effect profile, be palatable and cost effective. Whilst a number of clinical trials and meta-analyses have attempted to identify which bowel preparation best meets these requirements, their results are contradictory. Although sodium picosulfate was used for most routine bowel preparation in our trust, we had noticed anecdotally that polyethylene glycol (PEG) solutions led to better preparation. We therefore aimed to conduct a service improvement project to better evaluate this finding.

Method We compared two PEG solutions (4 litre and 2 litre + ascorbic acid) and sodium picosulfate in relation to the above mentioned criteria. Bowel preparation quality was judged by blinded endoscopists using the Boston Bowel Preparation Scale (BBPS), patients’ views regarding taste and tolerability of preparations were assessed by Visual Analogue Scales and side effects were recorded using a structured questionnaire. Cost was assessed by prices in the British National Formulary.

Results 169 non-randomised patients were included in our evaluation. 4 litre and 2 litre PEG preparations yielded significantly better BBPS scores than sodium picosulphate of the right colon (2.44 and 2.35 vs 2.04 (p < 0.05)) and bowel overall (BBPS 7.52 and 7.54 vs 6.53 (p < 0.05)). There was no significant difference in the reported palatability of the preparations though both 4 litre and 2 litre PEG were considered less tolerable to consume (p < 0.05). Reported side effects such as abdominal cramps, anal irritation and bloating, were more common with PEG based preparations. Although there was a trend favouring the side effect profile of sodium picosulfate, statistical significance was only demonstrated when comparing picosulfate with 2 litre PEG solution.

Conclusion Despite poor patient tolerance and higher price, polyethylene glycol solutions provide superior bowel cleansing to sodium picosulphate.

Disclosure of interest None Declared.

References

1. Juluri et al. Meta-analysis: randomized controlled trials of 4-L polyethylene glycol and sodium phosphate solution as bowel preparation for colonosocopy. AP&T. 2010;32:171

2. Belsey et al. Systematic review: oral bowel preparation for colonoscopy. AP&T. 2007;25:373

3. Joint Formulary Committee. British National Formulary(66 Ed). London: BMJ Group and Pharmaceutical Press, 2014