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Optimal bowel preparation—a practical guide for clinicians

Nature Reviews Gastroenterology & Hepatology volume 11, pages 419–425 (2014)Cite this article

Subjects

Key Points

  • Efficacy and tolerability of bowel preparations are each important and are related to one another; as inadequate preparation has disruptive and costly consequences, efficacy is the more important clinical goal

  • Several medical factors including previous inadequate preparation, chronic constipation, use of opioids and obesity predict an increased risk of inadequate preparation; such patients should receive a more aggressive bowel preparation regimen

  • As patient factors such as having Medicaid insurance and English not being their first language predict failure to follow bowel preparation instructions, intensified education or patient navigation are indicated

  • Split-dose and same-day-dose bowel preparation regimens are more effective than dosing either the day or evening before; all preparations can be given as split doses

  • Brown rectal effluent on presentation predicts suboptimal preparation in 50% of patients, so large-volume enemas or additional oral preparation should be considered prior to attempting colonoscopy

  • During colonoscopy, bowel preparation quality should be described after cleaning efforts are completed; washing and suctioning to improve preparation quality are part of the expected effort of most colonoscopies

Abstract

High-quality bowel preparation is essential for effective colonoscopy. Bowel preparations are judged by their safety, efficacy and tolerability. Between efficacy and tolerability, efficacy is the clinical priority because inadequate preparations are disruptive and costly. Achieving high rates of adequate preparation depends first on using split-dose or same-day dosing. Patients who have medical predictors of inadequate preparation quality (for example chronic constipation) should be prescribed more aggressive preparations and patients who have factors that predict they are less likely to follow the instructions (such as English not being their first language) should receive intensified education. On the day of the procedure, patients with persistent brown effluent should be considered for large-volume enemas or additional oral preparation before proceeding with colonoscopy. During the procedure, preparation quality should be graded after the clean-up has been completed.

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Figure 1: An algorithm addressing key considerations in selecting bowel preparations.

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Acknowledgements

The work of this author is supported by a gift from Scott and Kay Schurz of Bloomington, IN, USA.

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  1. Department of Medicine, Indiana University School of Medicine, 550 University Boulevard, Indianapolis, 46202, IN, USA

    Douglas K. Rex

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D.K.R. declares that he is a member of the speakers' bureau and has received research support from Ferring Pharmaceuticals and Braintree Laboratories.

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Rex, D. Optimal bowel preparation—a practical guide for clinicians. Nat Rev Gastroenterol Hepatol 11, 419–425 (2014). https://doi.org/10.1038/nrgastro.2014.35

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