Bowel preparation for colonoscopy: European Society of Gastrointestinal Endoscopy (ESGE) guideline

Cloud-based multi-media systems for patient education and adherence: a pilot study to explore patient compliance with colonoscopy procedure preparation

Technology based patient education and adherence approaches are increasingly utilized to instruct and remind patients to prepare correctly for medical procedures. This study examines the interaction between two primary factors: patterns of patient adherence to challenging medical preparation procedures; and the demonstrated, measurable potential for cloud-based multi-media information technology (IT) interventions to improve patient adherence. An IT artifact was developed through prior design science research to serve information, reminders, and online video instruction modules to patients. The application was tested with 297 patients who were assessed clinically by physicians. Results indicate modest potential (43.4% relative improvement) for the IT-based approach for improving patient adherence to endoscopy preparations. Purposively designed cloud-based applications hold promise for aiding patients with complex medical procedure preparation. Health care provider involvement in the design and evaluation of a patient application may be an effective strategy to produce medical evidence and encourage the adoption of adherence apps.

A low-residue diet before colonoscopy tends to improve tolerability by patients with no differences in preparation quality: a randomized trial

BACKGROUND

The pre-colonoscopy diet traditionally involves 24 h of a clear liquid diet (CLD) in combination with a lavage solution; however, this preparation is poorly tolerated.

AIM

To compare the impact on the quality of bowel cleansing and tolerability of a CLD versus a low-residue diet (LRD).

METHODS

We performed a randomized trial. Subjects were randomized to CLD or LRD the day before of elective colonoscopy. All subjects received a 4-L preparation of single-dose PEG beginning 16 h prior to colonoscopy. The Boston bowel preparation scale was used to evaluate bowel cleansing; an adequate-quality preparation was defined as a score ≥ 2 per segment.

RESULTS

A total of 205 subjects were included with a mean age (SD) of 55.6 (12.6) years; 133 (64.9%) of them were female. A total of 105 subjects were randomized to receive CLD and 100 to LRD. No significant differences in bowel preparation quality were observed between groups according to the section of colon: right colon (70% vs. 73%, p = 0.08), transverse colon (82% vs. 79%, p = 0.062), or left colon (80% vs. 78.7%, p = 0.28). There was a tendency toward less-frequent nausea (p = 0.08) and vomiting (p = 0.07) in patients with LRD. No differences between groups regarding ADR (12% vs. 10%) were noted.

CONCLUSIONS

An LRD before colonoscopy resulted in a tendency toward improved tolerability by patients, with no differences in the quality of bowel preparation.

Optimal Timing of Simethicone Addition for Bowel Preparation Using Polyethylene Glycol Plus Ascorbic Acid

BACKGROUND

Colonic bubbles obscure the colonic mucosa during colonoscopy following bowel preparation with polyethylene glycol plus ascorbic acid (PEG-Asc). Simethicone is used to enhance visualization during colonoscopy. We aimed to determine the optimal timing of simethicone addition to improve bowel preparation using PEG-Asc.

METHODS

This prospective, randomized study enrolled patients undergoing elective colonoscopy from April 2017 to January 2018. They were randomly assigned to one of the following three groups: PEG-Asc only (control) or simethicone addition in the morning on the day of colonoscopy (PEG-S1) or in the evening of the day prior to colonoscopy (PEG-S2). The primary outcome was the quality of colon cleansing, and the secondary outcomes were the adenoma detection rate (ADR), polyp detection rate (PDR), and diminutive (≤ 5 mm) ADR.

RESULTS

In total, 240 patients were randomly allocated to the three groups; six patients were withdrawn. Of the 234 patients evaluated, 78, 79, and 77 were allocated to the control, PEG-S1, and PEG-S2 groups, respectively. The bubble scores of all colonic segments were lowest in the PEG-S2 group. There was no significant difference in ADR or PDR among the three groups. However, the diminutive ADR was significantly higher in the PEG-S2 group compared to the other two groups (control 5.1% vs. PEG-S1 8.9% vs. PEG-S2 20.8%; P = 0.009).

CONCLUSION

Addition of simethicone to PEG-Asc at the optimal time prevents the formation of air bubbles and so improves the quality of bowel preparation, especially enhancing diminutive ADR.

A Randomized Controlled Trial Comparing Colonoscopic Enema With Additional Oral Preparation as a Salvage for Inadequate Bowel Cleansing Before Colonoscopy

GOALS

The goal of this study was to evaluate the noninferiority of colonoscopic enema to additional oral preparation in salvage bowel cleansing for inadequate preparation for a morning colonoscopy.

BACKGROUND

Colonoscopic enema, administering additional cathartics into the right colon through the colonoscope accessory channel, is suggested to rescue poor bowel preparation for a colonoscopy but lacking comparative study.

STUDY

In this prospective, randomized, actively-controlled, parallel group, noninferiority trial, consecutive outpatients and health checkup recipients aged from 19 to 70 years with inappropriate bowel preparation during an elective colonoscopy were enrolled to receive either a colonoscopic enema of 1 L polyethylene glycol (PEG) (enema group) or additional oral intake of 2 L PEG (oral group). The primary endpoint was the proportion of adequate bowel preparation evaluated using the Boston Bowel Preparation Scale.

RESULTS

Overall, 131 participants were randomized. Adequate bowel preparation was achieved in 53% (35/66) of the enema group, which was significantly inferior to the oral group (81.5%; 53/67) with a difference of -28.5% (95% confidence interval, -44.1, -12.9; P=0.001). The largest difference in the proportion of adequate bowel preparation was observed in the right colon (57.8% in the enema group vs. 86.9% in the oral group; P<0.001), followed by the transverse colon (85.9% vs. 98.4%; P=0.017) and the left colon (90.6% vs. 96.7%; P=0.274).

CONCLUSIONS

The colonoscopic enema of 1 L PEG was inferior to the additional oral ingestion of 2 L PEG regarding efficacy as a salvage bowel preparation in adults with inadequate bowel cleansing for colonoscopy.

Quality optimisation in colonoscopy: a function of time of colonoscopy or bowel preparation

To test the hypothesis claimed in recent studies that quality of bowel preparation for colonoscopy could be influenced by the time of the day colonoscopy is performed. Do patients in morning list have better bowel preparation than those on the afternoon list? Retrospective analysis of 736 consecutive patients who had colonoscopy from 1^st August to 31^st December 2012. Patients with poor bowel preparation (Boston Bowel Prep Score 6 or less) were identified (n = 242). Colonoscopy reports of these patients analysed. Patients were stratified into two groups (am and pm) and results compared. Mean patient age 63.9 years (range 19-89). Male to female ratio 1:1. 92% of patients were given Moviprep. for bowel preparation. 32.9% (242/736) of patients were identified as having inadequate bowel preparation. 37.7% of morning list patients had poor bowel preparation. 26.7% of afternoon list patients had poor bowel preparation. 14.7% (108/736) had incomplete colonoscopy, of which 26.9% (29/108) were due to poor bowel preparation. The commonest reasons for incomplete examination were patient discomfort & bowel looping. Our study demonstrates that morning session patients had poorer bowel preparation than the afternoon session patients in contrast to published evidence in recent literature. This implies that timing of bowel preparation is probably more important than timing of colonoscopy. Poor bowel preparation does not seem to have a significant impact on the colonoscopy failure rate in this series.

Can a 1-day clear liquid diet with a split -dose polyethylene glycol overcome conventional practice patterns during the preparation for screening colonoscopy?

BACKGROUND/AIMS

A successful screening colonoscopy is closely linked to the quality of a bowel preparation. In this study, we aimed to determine the impact of a 1-day clear liquid diet (CLD) compared to a 3-day combined diet (CMD) accompanied by a split-dose regimen of polyethylene glycol and electrolyte lavage solution (PEG-ELS) for screening colonoscopy.

MATERIALS AND METHODS

This was a prospective, randomized, endoscopist-blinded study. Patients referred for screening colonoscopy were randomized to four groups as a 1-day CLD+PEG-ELS vs. a 1-day CLD+sulfate free (SF)-PEG-ELS and a 3-day CMD+PEG-ELS vs. a 3-day CMD+SF-PEG-ELS. An assessment of the quality of colon cleaning, tolerability to the preparation, and symptoms related to the preparation were recorded.

RESULTS

A total of 506 patients were enrolled in this study. The quality of bowel preparation was significantly inferior in the CMD+PEG-ELS group than CLD+PEG-ELS (p=0.004) and CMD+SF-PEG-ELS groups (p=0.007). There were no statistical differences among the groups in terms of the polyp detection rate. With respect to an easy rating of diet following and the consumption of laxative, there were no significant differences among the four groups. Gastric fullness and nausea/vomiting were pointed out much more, especially in the SF-PEG-ELS users (p=0.008 and p=0.004, respectively).

CONCLUSION

A 1-day CLD was not inferior to a 3-day CMD for colonoscopy preparation in terms of bowel cleaning, the polyp detection rate, and patient tolerance.

The Efficacy of Split-Dose Bowel Preparations for Polyp Detection: A Systematic Review and Meta-Analysis

INTRODUCTION

Split-dose bowel preparation leads to superior colon cleansing for colonoscopy. However, the magnitude of benefit in detecting colonic polyps is uncertain. We performed a systematic review to synthesize the data on whether using a split-dose bowel preparation regimen improves the detection of polyps when compared with other dosing methods or regimen products.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL databases (from the inception to June 2017) for randomized controlled trials that assessed the following: split-dose vs day-before, split-dose vs same-day (as colonoscopy), or different types of split-dose regimens for patients undergoing colonoscopy. We excluded studies limited to inpatients, children, or individuals with inflammatory bowel disease. We compared the number of patients undergoing colonoscopy with recorded detection of polyps, adenomas, advanced adenomas, sessile serrated polyps (SSPs), right colonic adenomas, right colonic polyps, or right colonic SSPs.

RESULTS

Twenty-eight trials fulfilled the inclusion criteria (8,842 participants). Of the seven trials comparing split-dose vs day-before bowel preparation regimens, there was an increased detection rate of adenomas (risk ratio (RR) 1.26, 95% confidence intervals (CIs): 1.10-1.44; 4 trials; 1,258 participants), advanced adenomas (RR 1.53, 95% CI: 1.22-1.92; 3 trials; 1,155 participants), and SSPs (RR 2.48, 95% CI: 1.21-5.09; 2 trials; 1,045 participants). Pooled estimates from 8 trials (1,587 participants) evaluating split-dose vs same-day bowel preparations yielded no evidence of statistical difference. For various split-dose vs split-dose trials, 14 fulfilled the criteria (5,496 participants) and no superior split-regimen was identified.

CONCLUSIONS

Compared with day-before bowel preparation regimens, split-dose bowel preparations regimens increase the detection of adenomas, advanced adenomas, and have the greatest benefit in SSP detection.

Does prucalopride reduce the dose of sodium phosphate in bowel preparation? A single-blind, randomized, and prospective study

OBJECTIVE

Sodium phosphate solution (NaP) in oral form is well known and frequently used for good quality bowel cleansing before a colonoscopy, but it carries the potential risk of electrolyte disturbance and dehydration. Prucalopride mitigates severe constipation by promoting colon motility. We evaluated the hypothesis that prucalopride plus one single dose of 45 mL NaP could be used as an alternative bowel preparation.

METHODS

Consenting adult patients undergoing a screening colonoscopy were randomized to receive 90 mL NaP (90-NaP) in two split doses or prucalopride 2 mg plus 45 mL NaP (P-NaP). Patients completed a questionnaire about adverse gastrointestinal symptoms and acceptability for bowel preparation. The effectiveness of colon preparation was evaluated according to the Ottawa bowel preparation scale.

RESULTS

Bowel cleansing was achieved in 92 patients with 90-NaP and in 97 patients with P-NaP. There was no significant difference in bowel cleansing level and adverse gastrointestinal symptoms between the two groups. However, more patients in the P-NaP group were willing to undertake the same regimen for a subsequent colonoscopy bowel preparation than those in 90-NaP group (82/97; 85% vs 51/92; 55%, P < 0.001).

CONCLUSION

The combination of 2 mg prucalopride and 45 mL NaP appeared to provide the same level of bowel cleansing, but it was more acceptable than the 90 mL NaP in split doses.

Comparison of asymmetric (low morning-dose) and standard split-dose regimen of PEG plus bisacodyl for bowel preparation: A randomized controlled trial

BACKGROUND

Reducing the morning dose of PEG solution may be a reliable strategy to improve the patient compliance of split-dose regimens without affecting efficacy of bowel cleansing.

AIMS

to compare the efficacy for bowel cleansing of an asymmetric split-dose regimen (25% of the dose on the day of colonoscopy and 75% on the day before) with the standard split-dose regimen.

METHODS

Outpatients were enrolled in a randomized, single-blind, non-inferiority clinical trial. All subjects received a split-dose preparation with a 2L PEG-citrate-simethicone plus Bisacodyl. Patients were randomly assigned to: group A, asymmetric split-dose regimen; group B, symmetric split-dose regimen. Primary endpoint was the proportion of adequate bowel cleansing.

RESULTS

Split-dose was taken by 81 and 80 patients in group A and B. Adequate bowel cleansing was achieved in 92.6% and 92.5% patients in group A and B (p = 1.000). No differences were observed regarding Boston Bowel Preparation Scale total score, adenoma detection rate and scores of each colon segment.

CONCLUSIONS

The reduction of morning dose of PEG in a split-dose regimen is not inferior to the standard split-dose regimen in achieving an adequate bowel cleansing. However, further studies are needed to evaluate whether asymmetric preparation is associated to a higher tolerability compared to symmetric split-dose regimen. (NCT03146052).

Novel 1 L polyethylene glycol-based bowel preparation (NER1006): proof of concept assessment versus standard 2 L polyethylene glycol with ascorbate - a randomized, parallel group, phase 2, colonoscopist-blinded trial

Background

Colonoscopy requires colon cleansing. For this, many polyethylene glycol (PEG)-based preparations still require a high preparation-volume intake. Using an increased osmotic load with ascorbate (Asc), five new low-volume PEG-based bowel preparations (LVPEG) were tested for clinical proof of concept.

Methods

This two-part, open-label study examined preparation-volumes of 1–1.25 L and total required fluid volumes of 2–3 L. Part 1, in healthy volunteers, used mean cumulative 24-h stool weight (target > 2750 g) to identify a lead candidate. Part 2 was endoscopist-blinded: patients undergoing screening colonoscopy were randomized before treatment with the selected lead, one of two variants of it, or the control 2 L PEG + Asc. Two primary endpoints were used for proof of concept demonstration: mean 24-h stool weight and bowel cleansing success (Harefield Cleansing Scale).

Results

A total of 120 subjects (30 per group) were enrolled/randomized 1:1:1:1 (max 40:60 gender ratio) per completed Part. In Part 1, LVPEG-3 achieved the largest mean stool weight (3399 g: P < 0.0001 vs target) and was selected for Part 2. In Part 2, stool weights exceeded the target, notably for LVPEG-4 (3215 g: P < 0.001), which achieved 100% cleansing success after a total required fluid intake of 2 L. The control achieved 90% cleansing success. Adverse events were few, gastrointestinal in nature and similar between groups.

Conclusions

LVPEG-4 achieved a clinically useful combination of cleansing, safety/tolerability and low consumption volume: 1 L preparation + 1 L required additional fluid. Named NER1006, LVPEG-4 demonstrated clinical proof of concept and warrants further investigation.

Trial registration

October 2012.

Identifier: NCT01714466. EudraCT: 2012–003052-37

The trial was prospectively registered.

Electronic supplementary material

The online version of this article (10.1186/s12876-019-0988-y) contains supplementary material, which is available to authorized users.

Low-Volume Polyethylene Glycol Improved Patient Attendance in Bowel Preparation Before Colonoscopy: A Meta-Analysis With Trial Sequential Analysis

Background: Polyethylene glycol (PEG) has been regarded as the primary recommendation for bowel preparation before colonoscopy. However, a conclusive conclusion has not yet been generated.

Aim: We performed this updated meta-analysis to further investigate the comparative efficacy and safety of low volume preparation based on PEG plus ascorbic acid related to 4L PEG.

Methods: A systematic search was conducted to retrieve potential randomized controlled trials (RCTs) in PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) from January 2000 to April 2018. Two independent searchers critically searched all potential citations, extracted data, and appraised risk of bias accordingly. Moreover, we used the STATA 12.0 and trial sequential analysis (TSA) 0.9 to complete all analyses.

Results: A total of 13 RCTs enrolling 3,910 patients met inclusion criteria. Meta-analysis based on PP analysis indicated that compared to standard volume PEG regime, low volume regime improved patient compliance RR = 1.01; 95% CIs = 1.00, 1.03; P = 0.143 (≥75% intake); RR = 1.07; 95% CIs = 1.00, 1.14; P = 0.046 (100% intake), the willingness to repeat the same regime (RR = 1.30; 95% CIs = 1.07, 157; P = 0.007), and patient acceptability (RR = 1.18; 95% CIs = 1.07, 1.29; P = 0.001), and decreased the overall adverse events (RR = 0.86; 95% CIs = 0.77, 0.96; P = 0.009). However, no difference was observed between these two different solutions for bowel preparation efficacy (RR = 0.98; 95% CIs = 0.95, 1.02; P = 0.340). These all results were further confirmed by TSA.

Conclusions: The effect of low volume regime was not inferior to the standard volume PEG regime, and low volume regime was associated with better compliance when subjects ingested all the solution, willingness to repeat the same regime, higher acceptability, and lower nausea in non-selected population.

Performance measures for small-bowel endoscopy: A European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative

The European Society of Gastrointestinal Endoscopy (ESGE) together with the United European Gastroenterology (UEG) recently developed a short list of performance measures for small-bowel endoscopy (i.e. small-bowel capsule endoscopy and device-assisted enteroscopy) with the final goal of providing endoscopy services across Europe with a tool for quality improvement. Six key performance measures both for small-bowel capsule endoscopy and for device-assisted enteroscopy were selected for inclusion, with the intention being that practice at both a service and endoscopist level should be evaluated against them. Other performance measures were considered to be less relevant, based on an assessment of their overall importance, scientific acceptability, and feasibility. Unlike lower and upper gastrointestinal endoscopy, for which performance measures had already been identified, this is the first time small-bowel endoscopy quality measures have been proposed.

Standards of diagnostic colonoscopy for early-stage neoplasia: Recommendations by an Asian private group

BACKGROUND AND AIM

In recent years, the incidence of colorectal cancer has been increasing, and it is now becoming the major cause of cancer death in Asian countries. The aim of the present study was to develop Asian expert-based consensus to standardize the preparation, detection and characterization for the diagnosis of early-stage colorectal neoplasia.

METHODS

A professional group was formed by 36 experts of the Asian Novel Bio-Imaging and Intervention Group (ANBI2 G) members. Representatives from 12 Asia-Pacific countries participated in the meeting. The group organized three consensus meetings focusing on diagnostic endoscopy for gastrointestinal neoplasia. The Delphi method was used to develop the consensus statements.

RESULTS

Through the three consensus meetings with debating, reviewing the literature and regional data, a consensus was reached at third meeting in 2016. The consensus was reached on a total of 10 statements. Summary of statements is as follows: (i) Adequate bowel preparation for high-quality colonoscopy; (ii) Antispasmodic agents for lesion detection; (iii) Image-enhanced endoscopy (IEE) for polyp detection; (iv) Adenoma detection rate for quality indicators; (v) Good documentation of colonoscopy findings; (vi) Complication rates; (vii) Cecal intubation rate; (viii) Cap-assisted colonoscopy (CAC) for polyp detection; (ix) Macroscopic classification using indigocarmine spray for characterization of colorectal lesions; and (x) IEE and/or magnifying endoscopy for prediction of histology.

CONCLUSION

This consensus provides guidance for carrying out endoscopic diagnosis and characterization for early-stage colorectal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early-stage colorectal neoplasia.

Strategies to optimise the quality of bowel cleansing

Colonoscopy is the gold standard procedure for detecting neoplastic lesions of the colon and its efficiency is closely linked to the quality of the procedure. Adequate bowel preparation is a crucial factor in achieving the recommended quality indicators, but poor preparation has been reported in up to 30% of outpatients referred for colonoscopy. Consequently, over recent years, a number of studies have developed strategies to optimise bowel cleansing by improving adherence and tolerance to and the efficacy of the bowel preparation. Moreover, the identification of risk factors for inadequate bowel cleansing has led to tailored bowel preparation strategies being designed, with promising results. We aimed to review studies that assessed risk factors for inadequate bowel preparation and strategies to optimise bowel cleansing in patients at high risk of having poor preparation.

Antihyperglycemic therapy during colonoscopy preparation: A review and suggestions for practical recommendations

Patients with diabetes have distinct risks during precolonoscopy bowel preparation, caused by change of diet, change of antihyperglycemic medication regimens and diabetes-related complications and comorbidities. These risks include hypoglycemia, water and electrolyte imbalance, acute renal failure, lactic acidosis, ketoacidosis and low quality of bowel preparation. Here we review the existing literature and present recommendations from a subcommittee of the Israeli National Diabetes Council for primary care physicians and gastroenterologists. The instructions include general suggestions on diet and glucose monitoring and specific recommendations on timing of modification or cessation of each of the antihyperglycemic medication types to ensure patient safety during bowel preparation.

A systematic review and cost analysis of repeat colonoscopies due to inadequate bowel cleansing in five European countries

Background: Colonoscopies are carried out for a range of reasons including for the detection of colon cancer and investigation of abdominal and bowel related symptoms. Inadequate preparation can increase the burden of repeat procedures.Methods: A systematic review aimed to identify the rate of repeat colonoscopies due to inadequate bowel preparation in France, Germany, Italy, Spain and the United Kingdom. The information obtained populated a decision analytic model to estimate the cost implications of inadequate bowel cleansing in the same five countries. The model explored scenarios by comparing one and two-litre polyethylene glycol-based bowel preparation.Results: The systematic review identified 14 eligible studies reporting on the proportion of patients with inadequate bowel cleansing indicated for a repeat procedure. Data were available for Italy (27.5%-35.9%), Spain (63%) and the UK (24.5%) only. The decision analytic model demonstrates that improving the proportion of adequate bowel cleansing at first colonoscopy is likely to generate cost savings.Conclusions: Based on the available evidence, increasing the proportion of people who have adequate bowel cleansing at index colonoscopy will likely have financial benefits in Italy, Spain and the UK. A paucity of data, for France and Germany, limits the robustness of conclusions in these countries.

Higher dose of simethicone decreases colonic bubbles and increases prep tolerance and quality of bowel prep: Meta-analysis of randomized controlled trials

BACKGROUND

Antifoaming agents, such as simethicone, may facilitate mucosal inspection during colonoscopy. However, conflicting results have been reported with regard to the impact of simethicone on quality of bowel preparation and adenoma detection rate (ADR).

AIM

To perform a meta-analysis of trials that have compared simethicone vs placebo during colonoscopy.

METHODS

A reproducible literature search of multiple medical databases yielded eleven studies (n = 2605) for inclusion. Studies were compared for quality of bowel preparation, bubbles quality, ADR, and tolerability. Two reviewers independently scored the identified studies for methodology and abstracted pertinent data. Pooling was conducted by both fixed-effects and random-effects models. Relative risk (RR) estimates with a 95% confidence interval (CI) were calculated. Heterogeneity was assessed by I-squared index (I²) statistics.

RESULTS

Patients’ demographic characteristics were comparable in all studies. Of the 2605 patients, 1300 were in the simethicone group, whereas 1305 were in the placebo group. Inadequate bowel preparation was much lower in the simethicone group than in the placebo group [13% vs 24.6%; RR = 0.51 (0.31-0.82); P < 0.0001]. The placebo group was more likely to have significant colonic bubbles than was the simethicone group [35% vs 8%; RR = 1.49 (1.25-1.76); P = 0.0001]. Use of simethicone resulted in a slight, statistically significant increase in ADR compared with the placebo group [26.6% vs 21.6%, RR = 1.07 (1.01-1.13); P = 0.02]. Higher doses of simethicone (> 478 mg) were more likely to result in significant reduction of inadequate bowel preparation, colonic bubbles, and to improve ADR.

CONCLUSION

Adding simethicone improved the quality of bowel preparation, visualization, tolerability, and, eventually, ADR.

Quality measures improving endoscopic screening of colorectal cancer: a review of the literature

Colorectal cancer (CRC) is a major health-care problem all over the world and CRC screening is effective in reducing mortality and increasing the 5-year survival. Colonoscopy has a central role in CRC screening. It can be performed as a primary test, as a recall policy after a positive result of another screening test, and for surveillance. Since effectiveness of endoscopic screening depends on adequate detection and removal of colonic polyps, consistent quality measures, which are useful in enhancing the diagnostic yield of examination, are essential. Areas covered: The aim of this review is to analyze current evidence from literature supporting quality measures able to refine endoscopic screening of colorectal cancer. Expert commentary: Quality measures namely a) time slot allotted to colonoscopy, b) assessment of indication, c) bowel preparation, d) Cecal intubation, e) withdrawal time, f) adenoma detection rate, g) proper management of lesions (polypectomy technique, polyps retrieval rate and tattooing of resection sites), and h) adequate follow-up intervals play a key role in identifying malignant and at-risk lesions and improving the outcome of screening. Adherence to these quality measures is critical to maximize the effectiveness of CRC screening, as well as, a proper technique of colonoscopy and a quality report of the procedure. Among all recommended measures, adenoma detection rate is the most important and must be kept above the recommended quality threshold by all physicians practicing in the setting of screening.

Same-Day Regimen as an Alternative to Split Preparation for Colonoscopy: A Systematic Review with Meta-Analysis

Background

Split bowel preparation is the best regimen for colonoscopy. However, the same-day regimen can represent a valid alternative, but its use is limited by concerns about its cleansing ability, and to date, no convincing data support its use for routine colonoscopies.

Aim

To evaluate the cleansing, compliance, and adverse event rates of the same-day compared to the split regimen.

Results

A systematic literature search and meta-analysis was performed. Ten studies were included for a total of 1807 patients (880 in the same-day group and 927 in the split group). Overall, 85.3% patients in the same-day group vs. 86.3% in the split group had an adequate cleansing. Compliance was high for both, although patients were more compliant with the split than with the same-day prep (89.7% for same-day vs. 96.6% for split regimen). Sleep disturbance was more frequent in the split group, while nausea and vomit were more frequent in the same-day group. In the subgroup analysis, polyethylene glycol obtained a better cleansing rate when given as a split dose, with similar compliance and adverse events rates with both regimens.

Conclusion

Split and same-day regimens are both useful in bowel cleaning before colonoscopy with a different pattern of adverse events and better compliance for split preparations. Endoscopists can consider the same-day preparation as a valid alternative, especially when the split preparation does not fit the patients' needs.

Evaluating Information Quality of Revised Patient Education Information on Colonoscopy: It Is New But Is It Improved?

BACKGROUND

Previous research indicates that patients and their families have many questions about colonoscopy that are not fully answered by existing resources. We developed revised forms on colonoscopy bowel preparation and on the procedure itself.

OBJECTIVE

As the goal of the revised materials is to have improved information relative to currently available information, we were interested in how revised information compared with what is currently available in terms of information quality and patient preference.

METHODS

Participants were asked to review one at a time the Revised and Current versions of Colonoscopy bowel preparation instructions (study 1) and About Colonoscopy (study 2). The order of administration of the Revised and Current versions was randomly counterbalanced to assess order effects. Respondents rated each form along the following dimensions: amount, clarity, trustworthiness, readability and understandability, how new or familiar the information was, and reassurance. Participants were asked which form they preferred and 4 questions about why they preferred it. Open-ended questions asked participants to describe likes and dislikes of the forms and suggestions for improvement.

RESULTS

The study 1 and study 2 samples were similar. Overall, in study 1, 62.4% preferred the Revised form, 28.1% preferred the Current form, and 6.7% were not sure. Overall, in study 2, 50.5% preferred the Revised form, 31.1% preferred the Current form, and 18.4% were not sure. Almost 75% of those in study 1 who received the Revised form first, preferred it, compared with less than half of those who received it first in study 2. In study 1, 75% of those without previous colonoscopy experience preferred the Revised form, compared with more than half of those who had previously undergone a colonoscopy. The study 1 logistic regression analysis demonstrated that participants were more likely to prefer the Revised form if they had viewed it first and had no previous experience with colonoscopy. In study 2, none of the variables assessed were associated with a preference for the Revised form. In comparing the 2 forms head-to-head, participants who preferred the Revised form in study 1 rated it as clearer compared with those who preferred the Current form. Finally, many participants who preferred the Revised form indicated in the open-ended questions that they liked it because it had more information than the Current form and that it had good visual information.

CONCLUSIONS

This study is one of the first to evaluate 2 different patient education resources in a head-to-head comparison using the same participants in a within-subjects design. This approach was useful in comparing revised educational information with current resources. Moving forward, this knowledge translation approach of a head-to-head comparison of 2 different information sources could be taken to develop and refine information sources on other health issues.

Effect of supplemental simethicone for bowel preparation on adenoma detection during colonoscopy: A meta-analysis of randomized controlled trials

BACKGROUND AND AIM

Although several randomized controlled trials (RCTs) have reported that supplemental simethicone (SIM) can improve bowel preparation based on polyethylene glycol, there is no consensus as to whether SIM can ultimately increase the adenoma detection rate (ADR) during colonoscopy. A meta-analysis was performed to assess the effect of SIM on ADR during colonoscopy.

METHODS

Databases including PubMed, EMBASE, and the Cochrane Library were searched to find relevant RCTs. RCTs evaluating the effect of pre-procedure SIM on the ADR during colonoscopy were finally included, and fixed effect models were applied.

RESULTS

Six trials involving 1855 patients were finally included. The present meta-analysis suggested that the ADR during colonoscopy was significantly increased by supplemental SIM (27.9% vs 23.3%, P = 0.02), with a relative risk of 1.20 (95% confidence interval 1.03-1.39). Subgroup analysis suggested that supplemental SIM may be more useful to improve ADR during colonoscopy in endoscopic centers with low baseline ADR.

CONCLUSIONS

Supplemental SIM for bowel preparation based on polyethylene glycol is useful to improve the ADR during colonoscopy.

Impact of high-volume, intermediate-volume and low-volume bowel preparation on colonoscopy quality and patient satisfaction: An observational study

Background

Although optimal bowel preparation is essential for high-quality screening colonoscopy, documentation of preparation quality, patient satisfaction and adherence is scarce.

Aim

The aim of this article is to compare low-volume (LV, 300 ml sodium picosulfate), intermediate-volume (IV, 2 l polyethylene glycol, PEG + ascorbic acid and sodium ascorbate), and high-volume (HV, 4 l PEG) purgatives.

Results

A total of 5000 individuals (50.5% women) were enrolled between March 2015 and July 2017 (LV:IV:HV = 3.61:1.54:1). Overall sex- and age-adjusted adenoma detection rate was 25.4% (LV 23.8%, IV 25.4%, HV 29.8%), median age was 59.6 years, and cleansing was successful in 96.8%. Success rates of bowel cleansing were highest with HV (97.6%), followed by LV (97.2%) and IV (95.3%) with OR 2.04 (CI 95% 1.20-3.45, p = 0.008) and OR 1.79 (CI 95% 1.27-2.50, p = 0.001), respectively, compared to IV. A total of 93.5% of the LV group would use the same purgative in the future, 73.2% of IV and 69.4% of HV. A total of 84.4% would prefer overnight preparation, 12.1% same-day preparation.

Conclusion

All purgatives investigated showed good bowel cleansing quality results, patient satisfaction and compliance. Improvement in patient information might lead to even higher participation rates in screening colonoscopy since one in five patients stated that bowel preparation worried him or her most prior to colonoscopy.

Efficacy of 0.5-L vs 1-L polyethylene glycol containing ascorbic acid as additional colon cleansing methods for inadequate bowel preparation as expected by last stool examination before colonoscopy

BACKGROUND

No consensus has been reached in patients suspected of having inadequate bowel preparation regarding optimal salvage methods, which negatively affects the efficacy and quality of colonoscopy. The most ideal and reasonable rescue option involves early suspicion and identification of patients with inadequate preparation before sedation, additional oral ingestion of a suitable preparation formulation, and same-day colonoscopy.

AIM

To compare 0.5-L and 1-L polyethylene glycol containing ascorbic acid (PEG + Asc) as additional bowel cleansing methods after a 2-L split-dose PEG + Asc regimen in patients with expected inadequate bowel preparation before colonoscopy.

METHODS

Individuals with expected inadequate bowel preparation based on last stool form, such as turbid liquid, particulate liquid, or liquid with small amounts of feces, were randomized to either a 0.5-L PEG + Asc group or a 1-L PEG + Asc group. The primary endpoint was bowel preparation as assessed using the Aronchick bowel preparation scale (ABPS) and Boston bowel preparation scale (BBPS) scores. The secondary endpoints were cecal intubation time, withdrawal time, polyp detection rate (PDR), adenoma detection rate (ADR), individual compliance with additional PEG + Asc, and patient satisfaction.

RESULTS

Initially, 98 patients were included, but 8 were later excluded due to withdrawal of consent to participate in the study. Adequate bowel preparation (as assessed by ABPS) was observed in 80.9% (38/47) of subjects in the 0.5-L group and in 88.4% (38/43) of subjects in the 1-L group (P = 0.617). Mean total BBPS was 6.7 points in the 0.5-L group and 7.0 points in the 1-L group (P = 0.458). ADRs and PDRs were similar in the two groups, and cecal intubation and withdrawal times were not significantly different. However, mean patient satisfaction score was significantly higher in the 0.5-L group (P = 0.041).

CONCLUSION

The bowel cleaning efficacy of additional 0.5-L PEG + Asc was not inferior to that of 1-L PEG + Asc. Additional 0.5-L PEG + Asc is worthwhile when inadequate bowel preparation is expected before colonoscopy.

Quality assurance of colonoscopy within the Dutch national colorectal cancer screening program

Colorectal cancer (CRC) screening is capable of reducing CRC-related morbidity and mortality. Colonoscopy is the reference standard to detect CRC, also providing the opportunity to detect and resect its precursor lesions: colorectal polyps. Therefore, colonoscopy is either used as a primary screening tool or as a subsequent procedure after a positive triage test in screening programs based on non-invasive stool testing or sigmoidoscopy. However, in both settings, colonoscopy is not fully protective for the occurrence of post-colonoscopy CRCs (PCCRCs). Because most PCCRCs are the result of colonoscopy-related factors, a high-quality procedure is of paramount importance to assure optimal effectiveness of CRC screening programs. For this reason, at the start of the Dutch fecal immunochemical test (FIT)-based screening program, quality criteria for endoscopists performing colonoscopies in FIT-positive screenees, as well as for endoscopy centers, were defined. In conjunction, an accreditation and auditing system was designed and implemented. In this report, we describe the quality assurance process for endoscopists participating in the Dutch national CRC screening program, including a detailed description of the evidence-based quality criteria. We believe that our experience might serve as an example for colonoscopy quality assurance programs in other CRC screening programs.

Comparison Between an Oral Sulfate Solution and a 2 L of Polyethylene Glycol/Ascorbic Acid as a Split Dose Bowel Preparation for Colonoscopy

BACKGROUND/AIMS

This study aimed to compare the efficacy and tolerability of an oral sulfate solution (OSS) versus 2 L of polyethylene glycol/ascorbic acid (2L-PEG/Asc) for bowel cleansing before colonoscopy.

METHODS

A prospective, single-center, single-blinded, noninferiority, randomized, controlled trial was performed. The primary outcome was the rate of successful bowel cleansing, evaluated using the Boston Bowel Preparation Scale (BBPS). Secondary outcomes were examination time, polyp, and adenoma detection rate (PDR and ADR), tolerability, and safety. Ease of use, palatability, intention to reuse, and satisfaction were evaluated using a questionnaire.

RESULTS

A total of 187 participants were randomized to receive either OSS (n=93) or 2L-PEG/Asc (n=94). Successful bowel cleansing was achieved in 86.0% (80/93) of the OSS group, which was noninferior to the 2L-PEG/Asc group (88.3%, 83/94), with a difference of -2.3% by ITT analysis [95% confidence interval (CI) -12.0 to +7.4]. The withdrawal time of the OSS group was significantly shorter than that of the 2L-PEG/Asc group (11.8±5.2 vs. 14.3±8.5; P=0.016). Ease of use, palatability, intention to reuse, and satisfaction were similar between the 2 groups. Adverse events were also similar between the 2 groups. Mucosal erythema (4.3%) and aphthous lesions (2.1%) were found only in the 2L-PEG/Asc group.

CONCLUSIONS

OSS was as effective as 2L-PEG/Asc for successful bowel cleansing and had acceptable tolerability. OSS is a promising and safe low-volume preparation alternative for colonoscopy. (Clinical trial registration number: NCT02761213.).

Bowel preparation for colonoscopy: what is best and necessary for quality?

PURPOSE OF REVIEW

Colonoscopy is recognizably, the best colon cancer prevention test, provided the quality of the preparation is adequate for detection of precancerous polyps but also allowing for accurate identification of margins, thereby facilitating complete endoscopic resection. As there are many aspects effecting colon prep outcomes, it is timely to review new standards for optimizing outcomes, including product selection based on patient demographics.

RECENT FINDINGS

New national guidelines have set a minimum quality threshold for adequacy and also defined a split day delivery for oral options as the "standard of care". Several new prep options have been recently released and these data are discussed.

SUMMARY

Optimizing the quality of colon preps has major implications for clinical practice. Clinicians must recognize new targets for standard of care, providing the best approach for each individual patient, considering variable factors which may otherwise compromise success.

Simethicone is retained in endoscopes despite reprocessing: impact of its use on working channel fluid retention and adenosine triphosphate bioluminescence values (with video)

BACKGROUND AND AIMS

Studies from our group and others demonstrate residual fluid in 42% to 95% of endoscope working channels despite high-level disinfection and drying. Additionally, persistent simethicone has been reported in endoscope channels despite reprocessing.

METHODS

Endoscopy was performed by using water or varied simethicone concentrations (0.5%, 1%, 3%) for flushing. After high-level disinfection/drying, we inspected endoscope working channels for retained fluid by using the SteriCam borescope. Working channel rinsates were evaluated for adenosine triphosphate (ATP) bioluminescence. Fourier transform infrared spectroscopy was performed on fluid droplets gathered from a colonoscope in which low-concentration simethicone was used.

RESULTS

Use of medium/high concentrations of simethicone resulted in a higher mean number of fluid droplets (13.5/17.3 droplets, respectively) and ATP bioluminescence values (20.6/23 relative light units [RLUs], respectively) compared with that of procedures using only water (6.3 droplets/10.9 RLUs; P < .001). Two automated endoscope reprocessing cycles resulted in return of a fluid droplet and ATP bioluminescence values to ranges similar to that of procedures that used only water (P = .56). Low-concentration simethicone did not increase the mean residual fluid or ATP bioluminescence values compared with procedures that used only water (5.8 droplets/15.6 RLUs). Fourier transform infrared analysis revealed simethicone in the endoscope working channel after use of low-concentration simethicone.

CONCLUSIONS

Use of medium/high concentrations of simethicone is associated with retention of increased fluid droplets and higher ATP bioluminescence values in endoscope working channels, compared with endoscopes in which water or low concentration simethicone was used. However, simethicone is detectable in endoscopes despite reprocessing, even when it is utilized in low concentrations. Our data suggest that when simethicone is used, it should be used in the lowest concentration possible. Facilities may consider 2 automated endoscope reprocessor cycles for reprocessing of endoscopes when simethicone has been used.

Sodium picosulphate or polyethylene glycol before elective colonoscopy in outpatients? A systematic review and meta-analysis

AIM

To determine the best option for bowel preparation [sodium picosulphate or polyethylene glycol (PEG)] for elective colonoscopy in adult outpatients.

METHODS

A systematic review of the literature following the PRISMA guidelines was performed using Medline, Scopus, EMBASE, Central, Cinahl and Lilacs. No restrictions were placed for country, year of publication or language. The last search in the literature was performed on November 20th, 2017. Only randomized clinical trials with full texts published were included. The subjects included were adult outpatients who underwent bowel cleansing for elective colonoscopy. The included studies compared sodium picosulphate with magnesium citrate (SPMC) and PEG for bowel preparation. Exclusion criteria were the inclusion of inpatients or groups with specific conditions, failure to mention patient status (outpatient or inpatient) or dietary restrictions, and permission to have unrestricted diet on the day prior to the exam. Primary outcomes were bowel cleaning success and/or tolerability of colon preparation. Secondary outcomes were adverse events, polyp and adenoma detection rates. Data on intention-to-treat were extracted by two independent authors and risk of bias assessed through the Jadad scale. Funnel plots, Egger's test, Higgins' test (I 2) and sensitivity analyses were used to assess reporting bias and heterogeneity. The meta-analysis was performed by computing risk difference (RD) using Mantel-Haenszel (MH) method with fixed-effects (FE) and random-effects (RE) models. Review Manager 5 (RevMan 5) version 6.1 (The Cochrane Collaboration) was the software chosen to perform the meta-analysis.

RESULTS

662 records were identified but only 16 trials with 6200 subjects were included for the meta-analysis. High heterogeneity among studies was found and sensitivity analysis was needed and performed to interpret data. In the pooled analysis, SPMC was better for bowel cleaning [MH FE, RD 0.03, IC (0.01, 0.05), P = 0.003, I 2 = 33%, NNT 34], for tolerability [MH RE, RD 0.08, IC (0.03, 0.13), P = 0.002, I 2 = 88%, NNT 13] and for adverse events [MH RE, RD 0.13, IC (0.05, 0.22), P = 0.002, I 2 = 88%, NNT 7]. There was no difference in regard to polyp and adenoma detection rates. Additional analyses were made by subgroups (type of regimen, volume of PEG solution and dietary recommendations). SPMC demonstrated better tolerability levels when compared to PEG in the following subgroups: "day-before preparation" [MH FE, RD 0.17, IC (0.13, 0.21), P < 0.0001, I 2 = 0%, NNT 6], "preparation in accordance with time interval for colonoscopy" [MH RE, RD 0.08, IC (0.01, 0.15), P = 0.02, I 2 = 54%, NNT 13], when compared to "high-volume PEG solutions" [MH RE, RD 0.08, IC (0.01, 0.14), I 2 = 89%, P = 0.02, NNT 13] and in the subgroup "liquid diet on day before" [MH RE, RD 0.14, IC (0.06,0.22), P = 0.0006, I 2 = 81%, NNT 8]. SPMC was also found to cause fewer adverse events than PEG in the "high-volume PEG solutions" [MH RE, RD -0.18, IC (-0.30, -0.07), P = 0.002, I 2 = 79%, NNT 6] and PEG in the "low-residue diet" subgroup [MH RE, RD -0.17, IC (-0.27, 0.07), P = 0.0008, I 2 = 86%, NNT 6].

CONCLUSION

SPMC seems to be better than PEG for bowel preparation, with a similar bowel cleaning success rate, better tolerability and lower prevalence of adverse events.

Polyethylene glycol plus bisacodyl: A safe, cheap, and effective regimen for colonoscopy in the South Asian patients

BACKGROUND AND AIM

Data regarding the comparison of colonoscopic preparation regimens are still variable. We aimed to assess the adequacy and tolerability of two bowel preparation regimens for afternoon colonoscopy.

METHODS

In a randomized, investigator-blinded trial, two preparation regimens [4-L split-dose polyethylene glycol-electrolytes (PEG-ELS) and 2-L PEG-ELS plus bisacodyl) were compared in terms of bowel cleansing efficacy and adverse effects.

RESULTS

The mean (±SD) age (years) of the 4-L split-dose PEG-ELS group (N = 147) and the 2-L PEG-ELS plus bisacodyl (N = 155) were 44.09 (±15.62) (M:F : 2:1) and 44.12 years (±15.61) (M:F : 1.7:1), respectively. Percentage of patients with excellent and good preparation was higher in the 4-L split-dose PEG-ELS regimen compared with the 2-L PEG-ELS plus bisacodyl regimen (22.44 vs 17.41 and 44.21% vs 36.12%). Percentage of patients with fair and poor preparation was lower in 4-L split-dose PEG-ELS regimen compared with the 2-L PEG-ELS plus bisacodyl regimen (21.08% vs 27.74% and 12.24% vs 18.70%). In comparison with the 2-L PEG-ELS plus bisacodyl group, the incidences of abdominal pain (11% vs 15%), bloating (9% vs 12.24%), nausea/vomiting (8.38% vs 9.52%), and sleep disturbance (11% vs 12%) were slightly more common in the 4-L split-dose PEG-ELS group. There were no statistically significant differences between the two regimens with regard to bowel cleansing efficacy and adverse events.

CONCLUSIONS

The 2-L PEG-ELS plus bisacodyl (10 mg) preparation is as efficacious as the 4-L split-dose PEG-ELS regimen for afternoon colonoscopy. Optimal preparation for colonoscopy can be achieved with the 2-L PEG-ELS plus bisacodyl regimen with slightly fewer adverse events and lower cost compared to the 4-L split-dose PEG-ELS regimen.

Quality indicators in colonoscopy. The colonoscopy procedure

The aim of the project this paper is part of was to propose quality and safety procedures and indicators to facilitate quality improvement in digestive endoscopy units. In this second issue, procedures and indicators are suggested regarding colonoscopy. First, a diagram charting the previous and subsequent steps of colonoscopy was designed. A group of experts in health care quality and/or endoscopy, under the auspices of the Sociedad Española de Patología Digestiva (SEPD), performed a qualitative review of the literature regarding colonoscopy-related quality indicators. Subsequently, using a paired-analysis method, the aforementioned literature was selected and analyzed. A total of 13 specific indicators were found aside of the common markers elsewhere described, ten of which are process-related (one pre-procedure, seven procedure, and two post-procedure markers) while the remaining three are outcome-related. Quality of evidence was assessed for each one of them using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) classification.

Which Patient-Related Factors Determine Optimal Bowel Preparation?

PURPOSE OF REVIEW

Adequate bowel cleansing before colonoscopy is a simple concept but the high rate of inadequate or incomplete bowel cleanliness and its consequences have been the subject of many studies, guidelines, and meta-analysis. The complexity resides in all the factors surrounding preparation intake such as type and regimen of bowel preparation, diets, compliance, and also patient-related factors that all influence quality of the bowel preparation. The purpose of this review is to focus specifically on patient-related factors and their challenges. Patients with lower GI bleeding are excluded from this review.

RECENT FINDINGS

Patient factors that may be associated with a poor bowel preparation were searched for in the literature. With regard to patient's characteristics, higher age, male gender, and socio-economic status (lower income, Medicaid, and lower education) were all associated with higher rates of inadequate bowel preparation. Comorbidities such as inflammatory bowel disease (IBD), in-patients, body mass index (BMI), cirrhosis, constipation, and neurological condition as well as some pharmacotherapy were also associated with inadequate bowel preparation. Studies identifying predictive patient factors as well as those studying these patients in particular showed variability in the strength of the patient factor associations. Patients taking tricyclic antidepressant, narcotics, and those with neurological conditions were identified to have a stronger association with worse bowel cleanliness. Those can be implemented with the current recommendations of split-dosing. Identifying individual factors that can impact the quality of bowel cleanliness can be challenging. Some have been well-studied in the literature such as age, in-patient status, or constipation and others such as male gender or higher BMI have required more studies to clearly conclude on any possible association. In many studies, simple recommendations like walking 30 min during the preparation, and additional instructions or support have also been added to instructions to improve motility and compliance.

Preparation for colonoscopy: Recommendations by an expert panel in Italy

BACKGROUND

Despite several guidelines on bowel preparation being available, their applicability in Italy is poorly investigated.

AIMS

(1) To create expert-based recommendations for the Italian setting based on available international guidelines on bowel preparation for colonoscopy; (2) to assess consensus across the Italian endoscopy community.

METHODS

The study was conducted in 2 phases: (a) statements formulation, (b) assessment of consensus. For the first phase, 6 topics related to bowel preparation were identified: (1) efficacy/tolerability; (2) timing; (3) assessment of quality of bowel preparation; (4) factors associated with inadequate preparation; (5) patient education and (6) impact of organisational factors. For each topic, statements were produced and voted by a panel of experts. For consensus assessment, the invited participants were asked to rate the statements. The statement achieved a good level of agreement when at least 70% of voters agreed with it.

RESULTS

25 statements were agreed in the first phase. Agreement was not achieved by the endoscopy community for 7 statements, mainly concerning practical aspects (i.e. strategies for management of patients with inadequate preparation, organisational factors).

CONCLUSION

A clinically relevant consensus was achieved on the main topics of bowel preparation, such as the choice of laxative and the time of administration, and it may help to homogenize the colonoscopy practice in Italy. Nevertheless, there are a few country-specific preparation-related issues that need to be addressed.

Impact of diet restriction on bowel preparation for colonoscopy

Diet restriction is one of the difficult parts of bowel preparation for colonoscopy, and many patients do not follow instructions properly. Few studies have evaluated the impact of dietary restriction in real clinical setting. The aim of this study was to study the effect of diet control on bowel preparation with detailed investigation of unacceptable food list in order to reveal what kind of foods are most problematic in clinical practice.Prospective observational study was carried out at a university-affiliated hospital. Around 4 L polyethylene glycol solution was used for bowel preparation on the day of colonoscopy. Patients were allowed to have regular diet until lunch the day before colonoscopy and educated to control diet from 3 days before colonoscopy with information regarding an unacceptable foods list. Factors associated with inadequate bowel preparation were analyzed using univariate statistics and multivariate logistic regression analysis.Of the 245 patients included in the study, 68 patients (27.8%) followed the diet instructions. Fiber-rich vegetables were the most commonly taken unacceptable foods (N = 143, 58.4%). Inadequate bowel preparation (fair and poor by Aronchick scale) was 47.3%. In multivariate analysis, diabetes [odds ratio (OR) 2.878, 95% confidence interval (CI) 1.242-6.671], preparation to colonoscopy interval (OR 1.003, 95% CI 1.000-1.005) and consumption of foods disturbing bowel preparation (OR 2.142, 95% CI 1.108-4.140) were independent predictors of inadequate bowel preparation.We could identify substantially low compliance to diet instructions in real clinical practice. Consumption of any foods disturbing bowel preparation was significant factor predicting inadequate bowel preparation, even though we could not select specific food list compromising preparation significantly. Favorable bowel preparation was achieved in the subgroup compliant to diet restriction, suggesting that regular diet avoiding specific kinds of foods can be possible option for diet restriction before colonoscopy.

A comparative review of use of sulphate and phosphate salts for colonoscopy preparations and their potential for nephrotoxicity

Background and study aims  Colonoscopy is a widely used diagnostic procedure which requires prior cleansing of the bowel. Many different bowel cleansing preparations have been developed, all of which have specific advantages and disadvantages. This review compares two low-volume high-osmolarity bowel cleansing preparations, oral phosphate salts and oral sulphate salts, with a particular focus on risk of nephrotoxicity. Patients and methods  An electronic search of the Medline database was performed using the search terms "(phosphates OR sulfates) AND cathartics [MeSH Term] AND kidney" restricted to humans with a cut-off date of December 31, 2016. Results  Introduction of oral phosphate salts offered the advantage of low intake volume and low risk of bowel irritation compared to previous options. However, phosphate salts have been associated with renal toxicity (acute phosphate nephropathy [APN]), thought to arise due to perturbations of calcium and phosphate homeostasis as a consequence of increases in serum phosphate. This results in high concentrations of calcium phosphate in the distal tubule and collecting ducts of the kidney, where it may precipitate. Although APN is rare, it may lead to permanent kidney damage. For this reason, phosphate salts are contraindicated in vulnerable patient groups. As an alternative to phosphate salts, oral sulphate salts have recently been introduced. Because sulphate absorption from the intestinal tract is saturable, serum sulphate concentrations increase only minimally after ingestion. Furthermore, excretion of sulphate in the kidney is not accompanied by calcium excretion and urine calcium levels are unchanged. For these theoretical reasons, use of sulphate salts as bowel cleansing solutions is not expected to lead to calcium precipitation in the nephron. Conclusions  Oral phosphate salts are no longer recommended for routine use as bowel cleansing preparations as they carry significant risk of kidney damage and a safer alternative is available in the form of oral sulphate solutions. To date, use of sulphate salts has not been associated with elevations in serum creatinine or other markers of renal impairment, nor with clinical manifestations of kidney injury. Nonetheless, experience with sulphate salts in everyday practice is limited and physicians should be vigilant in detecting potential safety issues.

The association among diet, dietary fiber, and bowel preparation at colonoscopy

BACKGROUND AND AIMS

Pre-colonoscopy dietary restrictions vary widely and lack evidence-based guidance. We investigated whether fiber and various other foods/macronutrients consumed during the 3 days before colonoscopy are associated with bowel preparation quality.

METHODS

This was a prospective observational study among patients scheduled for outpatient colonoscopy. Patients received instructions including split-dose polyethylene glycol, avoidance of vegetables/beans 2 days before colonoscopy, and a clear liquid diet the day before colonoscopy. Two 24-hour dietary recall interviews and 1 patient-recorded food log measured dietary intake on the 3 days before colonoscopy. The Nutrition Data System for Research was used to estimate dietary exposures. Our primary outcome was the quality of bowel preparation measured by the Boston Bowel Preparation Scale (BBPS).

RESULTS

We enrolled 201 patients from November 2015 to September 2016 with complete data for 168. The mean age was 59 years (standard deviation, 7 years), and 90% of colonoscopies were conducted for screening/surveillance. Only 17% and 77% of patients complied with diet restrictions 2 and 1 day(s) before colonoscopy, respectively. We found no association between foods consumed 2 and 3 days before colonoscopy and BBPS scores. However, BPPS was positively associated with intake of gelatin, and inversely associated with intake of red meat, poultry, and vegetables on the day before colonoscopy.

CONCLUSIONS

Our findings support recent guidelines encouraging unrestricted diets >1 day before colonoscopy if using a split-dose bowel regimen. Furthermore, we found no evidence to restrict dietary fiber 1 day before colonoscopy. We also found evidence to promote consumption of gelatin and avoidance of red meat, poultry, and vegetables 1 day before colonoscopy.

Phosphate nephropathy: an avoidable complication of bowel preparation for colonoscopy

It is known that oral sodium phosphate, used as bowel preparation for colonoscopy, can cause acute phosphate nephropathy, a potentially severe and irreversible form of acute kidney injury. Due to these safety concerns, guidelines have advised against the routine use of this agent for a decade. We present a case report and biopsy series that demonstrate that oral sodium phosphate is still being used and that cases of APN are still occurring, in Australia.

Validation of same-day bowel preparation regimen using 4L polyethylene glycol: Comparison of morning and afternoon colonoscopy

A split-dose regimen is the recommended method of bowel preparation for colonoscopy. However, for colonoscopy performed in the afternoon, same-day preparation is recommended rather than a split-dose regimen. No study has compared the efficacy of same-day bowel-cleansing for morning colonoscopy (MC) and afternoon colonoscopy (AC). The aims of this study were to evaluate the bowel-cleansing efficacy, adverse events, and patient tolerability of same-day bowel preparation for colonoscopy using 4L polyethylene glycol (PEG).The medical records of consecutive patients who underwent colonoscopy at our healthcare center over 3 months were retrospectively reviewed. Colonoscopy was performed between 10:00 and 16:00. Study subjects were assigned to the MC or AC group according to their colonoscopy start time (MC group, before 12:00; AC group, after 12:00). Study subjects were instructed to drink 500-mL PEG every 15 minutes. In the MC group, bowel cleansing was started at 05:00 and finished at 07:00. For the AC group, 2L PEG was consumed from 07:00, and the remaining 2L PEG was started 3 hours before colonoscopy. The composite safety profile included vital signs, laboratory test results, and questionnaire findings. Laboratory testing of subjects and completion of the questionnaire were performed before colonoscopy. The questionnaire asked about adverse events and tolerability of the bowel cleansing regimen. Bowel-cleansing efficacy was assessed using the Boston bowel preparation scale (BBPS). Bowel-cleansing efficacy, tolerability, and safety profile were compared between the 2 groups.Two hundred and ninety-one subjects were included (MC group, 169; AC group, 122).The BBPS did not differ between the 2 groups (7.3 ± 0.8 vs. 7.3 ± 0.8, P = .68). There were no instances of electrolyte imbalance or hemodynamic instability in either group. The tolerability of the bowel-cleansing regimen did not differ between the 2 groups (P = .59).The bowel-cleansing efficacy, safety profile, and patient tolerability of MC and AC were comparable. A same-day dose of 4L PEG is a feasible bowel preparation method.

Lifestyle Factors and Bowel Preparation for Screening Colonoscopy

Purpose

The quality of bowel preparation is a major determinant of the quality of colonoscopy. This study evaluated lifestyle factors, including usual dietary style, associated with bowel preparation.

Methods

This retrospective study evaluated 1,079 consecutive subjects who underwent complete colonoscopy from December 2012 to April 2014 at National Cancer Center of Korea. Questionnaires on bowel preparation were completed by the subjects, with the quality of bowel preparation categorized as optimal (excellent or good) or suboptimal (fair, poor or inadequate). Lifestyle factors associated with bowel preparation were analyzed.

Results

The 1,079 subjects included 680 male (63.0%) and 399 female patietns (37.0%), with a mean age of 49.6 ± 8.32 years. Bowel preparation was categorized as optimal in 657 subjects (60.9%) and as suboptimal in 422 (39.1%). Univariate analyses showed no differences between groups in lifestyle factors, such as regular exercise, alcohol intake, smoking, and dietary factor. Body mass index (BMI) > 25 kg/m² was the only factor associated with suboptimal bowel preparation on both the univariate (P = 0.007) and the multivariate (odds ratio, 1.437; 95% confidence interval, 1.104–1.871; P = 0.007) analyses.

Conclusion

Most lifestyle factors, including dietary patterns, exercise, alcohol intake and smoking, were not associated with suboptimal bowel preparation in Koreans. However, BMI > 25 kg/m² was independently associated with suboptimal bowel preparation. More intense preparation regimens before colonoscopy can be helpful in subjects with BMI > 25 kg/m².

Efficacy and safety of a new low-volume PEG with citrate and simethicone bowel preparation for colonoscopy (Clensia): a multicenter randomized observer-blind clinical trial vs. a low-volume PEG with ascorbic acid (PEG-ASC)

BACKGROUND AND STUDY AIMS

Quality of inspection during colonoscopy is strictly related to the level of cleansing. High-volume (PEG-based) solutions are highly effective and safe, but their high volume affects tolerability and compliance. The aim of this study was to compare a new low-volume PEG with citrate and simethicone solution (PMF 104,Clensia) with a low-volume PEG with ascorbic acid solution (PEG-ASC; Moviprep).

PATIENTS AND METHODS

 This was a multicenter, randomized, observer-blind, parallel-group, phase 3 clinical trial, where patients were randomized between PMF 104 and PEG-ASC. In both groups, patients were instructed to take a full-dose regimen the evening before if colonoscopy was scheduled before 11 am to 12 pm, or to take a split regimen if colonoscopy was scheduled after 11 am to 12 pm. The primary end-point was an equivalence between PMF104 and PEG-ASC in the rate of adequate level of cleansing (Ottawa scale ≤ 6), with safety, mucosal visibility, tolerability, acceptance and compliance being also assessed.

RESULTS

Of the 403 enrolled, 367 patients (Mean age [SD]: 55.6 (14.4) years; male:166 [45.2 %]) were included in the per protocol (PP) analysis: 184 being randomized in the PMF 104 group and 183 in the PEG-ASC group. Successful bowel cleansing was 78.3 % and 74.3 % in PMF104 and in PEG-ASC, respectively ( P  = 0.37). Both preparations were equally safe (mild adverse events were observed in 9.2 % and 9.3 % of patients in the PMF104 and in the PEG-ASC group, respectively) and acceptable (no or mild distress during the intake in 81.4 % and 80.8 % in the PMF104 in the PEG-ASC, respectively [ P  = 0.74]).

CONCLUSION

The new low-volume product Clensia is equivalent to the reference low-volume PEG-ASC in terms of bowel cleansing, safety and acceptance.

Effects of polyethylene glycol electrolyte powder combined with different agents in bowel preparation for colonoscopy in elderly patients with constipation

AIM

To evaluate the effects of polyethylene glycol electrolyte powder combined with different agents in bowel preparation for colonoscopy examination in elderly constipation patients.

METHODS

A total of 108 elderly patients with constipation who would undergo bowel preparation for colonoscopy were enrolled from March 2016 to May 2017, and they were prospectively randomized into three groups: A, B, and C (n = 36 each). Patients of group A only took polyethylene glycol electrolyte powder, patients of group B took polyethylene glycol electrolytes powder combined with lactulose, and patients of group C took polyethylene glycol electrolytes powder combined with folium sennae. The colon cleaning quality, gastrointestinal complications, and patient compliance were evaluated.

RESULTS

The bowel preparation score of group B (7.96 ± 0.75, 94.3%) was better than those of groups A (5.11 ± 1.02, 66.7%) and C (5.83 ± 1.13, 22.2%), and the difference was statistically significant (P < 0.05). The rate of gastrointestinal complications in group B (2.7%, 8.3%) was much lower than that of group C (13.8%, 25%). No significant difference was observed in patient compliance between groups A (66.7%), B (63.8%) and C (55.6%).

CONCLUSION

Polyethylene glycol electrolyte powder combined with lactulose could improve the cleaning quality of bowel preparation in elderly patients with constipation and has no obvious gastrointestinal complications, representing a more effective and safer method for bowel preparation.

Split-dose bowel cleansing with picosulphate is safe and better tolerated than 2-l polyethylene glycol solution

BACKGROUND

In physically less fit patients and patients requiring repeated exams, adequate bowel preparation for colonoscopy remains problematic, particularly because patients need to drink large volumes of unpleasant-tasting fluids. A further concern is potential unwarranted fluid shifts.

AIMS

This study aimed to compare the safety and burden of a small-volume sodium picosulphate/magnesium citrate preparation (SPS-MC) with a 2-l ascorbic-acid-enriched polyethylene glycol solution plus bisacodyl pretreatment (PEG-Asc+B).

PATIENTS AND METHODS

Patients referred for colonoscopy were randomized to SPS-MC or PEG-Asc+B administered as a split-dose regimen. Patients received advice on the recommended 4-l SPS-MC and 2-l PEG-Asc+B fluid intake. Safety was assessed by blood sampling before and after the preparation and during a 30-day follow-up period. A questionnaire assessed tolerability and perceived burden of the preparation.

RESULTS

A total of 341 patients underwent colonoscopy. Blood sampling showed a slight but significant decrease in sodium, chloride and osmolality and increase in magnesium in the SPS-MC group and a decrease in bicarbonate in the PEG-Asc+B group. Hyponatraemia and hypermagnesaemia without clinical signs were observed in 16 (14 SPS-MC) and 13 SPS-MC patients, respectively. Patients reported significantly fewer physical complaints and a significantly higher completion rate with SPS-MC. Patients receiving SPS-MC rated the intake as being easier and better tasting. In the event of a repeat colonoscopy, 59.7% of patients in the PEG-Asc+B and 93.6% of patients in the SPS-MC group would opt for the same preparation again.

CONCLUSION

Despite electrolyte shifts, both SPS-MC and PEG-Asc+B appeared clinically safe. From a patient's perspective, a small-volume preparation formula such as SPS-MC is preferred, resulting in fewer physical complaints and greater ease of intake.

Comparison of the Boston Bowel Preparation Scale with an Auditable Application of the US Multi-Society Task Force Guidelines

Background

Existing bowel preparation scales (BPS) only modestly predict interval to next colonoscopy. The US Multi-Society Task Force (MSTF) recommends repeating colonoscopies within the year if the preparation does not allow detection of polyps over 5 mm.

Aim

This study aims to assess reliability and validity of an auditable application of the MSTF compared with the Boston BPS (BBPS).

Methods

We compared an auditable application of MSTF guidelines termed the Montreal BPS (MBPS) with the BBPS using a total cut-off score ≥6 with each segment score ≥2 (BBPS2-6). In sensitivity analyses, we applied the MBPS using a cut-off of 3 mm rather than 5 mm and also assessed the BBPS using an adequacy threshold of total score ≥5 (BBPS5). Videos of 83 colonoscopies (eight for intra-rater agreements) were independently evaluated by nine physicians. Weighted kappas quantified intra- and inter-rater agreements. Associations between scores and clinical outcomes were assessed.

Results

The BBPS2-6 and 5 mm MBPS showed moderate to substantial intra-rater agreements (κ=0.44 to 0.63 and κ=0.50 to 0.53, respectively); inter-rater agreements were only fair to moderate and slight to moderate (κ=0.25 to 0.48 and κ=0.19 to 0.50, respectively). Similar results were noted using alternate thresholds of BBPS5 and 3 mm MBPS. No significant associations were found between scores and clinical outcomes.

Conclusion

For all scales, intra-rater kappas were superior to inter-rater values, the latter reflecting at best moderate agreement. This modest performance may reflect the dichotomized interpretation of the scales (adequate versus inadequate), differing from previous publications assessing scores as continuous variables. Further studies are required to optimally interpret bowel preparation scales with regard to interval to next colonoscopy.