The European Society of Gastrointestinal Endoscopy (ESGE) has released updates to its guideline on bowel preparation for colonoscopy, which were published in Endoscopy. These updates are based on evidence published since the 2013 version of the guideline. They provide clinically applicable recommendations on laxatives, diet, timing, patient information, and different potential scenarios.
Chairpersons of the Guideline Committee collaborated with subgroup leaders to perform targeted searches for relevant studies within Medline and the Cochrane Central Register of Controlled Trials. All referenced articles were published after the previous ESGE guideline and before January 2019. The Grading of Recommendations Assessment, Development, and Evaluation system was used to grade evidence and subsequent strength of each recommendation.
The following are the recommendations of the 2019 update to the ESGE Guideline, as well as the respective quality of their evidence.
Diet and Patient Information
• ESGE strongly recommends that patients consume a low-fiber diet the day before colonoscopy. Compared with clear liquid diets, low-residue diets (eg peeled fruits, cooked vegetables, meat, cheese, fish, and white breads) have shown associations with higher willingness, adherence, tolerability, and bowel cleanliness among patients in meta-analyses of 32 randomized controlled trials (RCTs).
• Enhanced instructions are also recommended for patients and may include telephone messages, social media, visual aids, or smartphone apps. A meta-analysis of 8 RCTs revealed better bowel cleanliness (P <.001), greater willingness to repeat bowel preparation (P =.006), and higher cecal intubation rate (P <.001) with enhanced instructions compared with regular instructions, which 3 more recent RCTs confirmed.
• ESGE strongly recommends not routinely using enemas in bowel preparation. Enemas have not demonstrated an ability to improve bowel cleansing and were associated with less acceptability of bowel preparation in 1 RCT.
• Prokinetic agents are not recommended for routine use in bowel preparation. However, this is a weak recommendation due to low-quality evidence, including a lack of consensus among 3 RCTs testing lubiprostone as a bowel cleansing agent (better cleansing was significant in just 1 study), as well as the need for more trials testing other prokinetic agents, such as itopride and mosapride.
• ESGE recommends supplementing bowel preparation with oral simethicone, though this is a weak recommendation. While a 2011 meta-analysis of 7 RCTs found no association between oral simethicone and increased bowel cleanliness, 3 out of 4 recent RCTs have reported the association; furthermore, simethicone has demonstrated an ability to reduce bubbles.
• Split-dose bowel preparation for elective colonoscopy is strongly recommended on the basis of high-quality evidence. A meta-analysis of 47 RCTs showed good to excellent bowel cleansing with split-dose regimens vs day-before preparation (odds ratio 2.51). For afternoon procedures, ESGE strongly recommends a same-day bowel preparation as a substitute for split dosing, which is supported by high-quality evidence in 25 RCTs.
• It is strongly recommended that the final dose of bowel preparation be initiated ≤5 hours before colonoscopy procedure and finished ≥2 hours before the start of the colonoscopy. Twenty-nine RCTs demonstrated that split-dose regimens yielded the highest gains in ≤3 hours of last dose and were statistically insignificant by 5 hours.
High- or low-volume polyethylene glycol (PEG)-based laxatives are strongly recommended, as are clinically validated non-PEG laxatives. Laxative choice should be customized for each individual based on risk for hydroelectrolyte disturbances. However, neither high- or low-volume PEG-based laxatives, nor non-PEG laxatives are recommended for those with congestive heart failure.
• Split-dose high-volume PEG has been confirmed as superior to split-dose low volume PEG in at least 6 trials.
• Low-volume 2L PEG + ascorbate has demonstrated noninferiority to high-volume PEG in 11 RCTs as well as reduced nausea and vomiting. This regimen is not recommended for those with glucose-6-phosphate dehydrogenase deficiency, phenylketonuria, or acute renal insufficiency with creatinine clearance <30 mL/min.
• Low-volume 2L PEG + citrate is not inferior to the above regimens and is associated with better acceptability and gastrointestinal tolerability than a high-volume solution. This solution is not recommended for those with unstable angina, acute renal insufficiency, or acute myocardial infarction. Evidence on this regimen lacks long-term data.
• Low-volume 1L PEG + ascorbate has shown noninferiority to oral sulfate solution, 2L PEG + ascorbate, and magnesium citrate + picosulphate, though comparison with high-volume PEG has not been undertaken. This regimen requires maintaining adequate hydration and is not recommended for individuals with acute renal insufficiency, phenylketonuria, glucose-6-phosphate or dehydrogenase deficiency.
• Low-volume 2L PEG + bisacodyl is noninferior to 2L PEG + ascorbate or high-volume PEG. Although, there have been some reports of high-dose bisacodyl leading to ischemic colitis.
• Magnesium citrate + picosulphate has demonstrated noninferiority to 2L PEG + ascorbate and high-volume PEG, though it is not recommended for those with acute kidney insufficiency, hypermagnesemia, or for those at risk for rhabdomyolysis or hypermagnesemia.
• Oral sulfate solution is noninferior to high-volume PEG and 2L PEG + ascorbate, and was found to be superior to magnesium citrate + picosulphate in 1 RCT. This regimen is not recommended for those with ascites, or acute renal insufficiency.
Laxatives for the Elderly
Current research is insufficient to identify a single superior regimen for the elderly. However, RCTs have shown that high-volume regimens are not well tolerated among elderly patients, and osmotically balanced PEGs are likely the best solution for elderly patients.
• The use of oral sodium phosphate is not recommended, particularly among high-risk individuals, due to a potential association with kidney damage.
Bowel Preparation for Specific Patient Types
• For those with inflammatory bowel disease, ESGE strongly recommends high- or low-volume PEG-based solutions, with low-volume solutions generally associated with better tolerability. This recommendation is supported by high-quality evidence.
• For acute lower gastrointestinal bleeding, PEG solutions are strongly recommended before colonoscopy
• For those with constipation, ESGE does not have a specific recommendation for bowel cleansing due to low-quality evidence.
• There was insufficient evidence to recommend a specific regimen for those who are pregnant and/or lactating, however, PEG regimens should be considered for strong indications for colonoscopy.
Inadequate Bowel Preparation
• To manage inadequate bowel preparation, ESGE strongly recommends repeating the colonoscopy within 1 year.
• In certain cases, if same- or next-day colonoscopy is indicated, the selected regimen should be based on careful assessment of the main causes of bowel preparation failure (a weak recommendation based on very little evidence).
• For hospitalized patients, it is strongly recommended that specific written or verbal instructions be given to both patient and staff. This recommendation is based on moderate quality evidence, with specific education on bowel preparation associated with a 3.49-times higher rate of adequate preparation in 18 studies.
This guideline will be considered for update in 2024 and any interim updates will be noted on the ESGE website.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Hassan C, East J, Radaelli F, et al. Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2019 [published online July 11, 2019]. Endoscopy. doi:10.1055/a-0959-0505