Systematic review: oral bowel preparation for colonoscopy

Development and validation of the Open-Source Automatic Bowel Preparation Scale

BACKGROUND AND AIMS

Insufficient bowel preparation accounts for up to 42% of missed adenomas in colonoscopy. However, major analysis programs found no correlation between adenoma detection rate and the human-rated Boston Bowel Preparation Scale (BBPS), indicating limitations of the scale. We therefore aimed to develop an Open-Source Automatic Bowel Preparation Scale (OSABPS) based on artificial intelligence that is correlated to the polyp detection rate.

METHODS

The OSABPS was trained on 50,000 frames from 20 colonoscopies from 3 hospitals. It involved quantifying the presence of fecal matter within the colonoscopy frames, using an approach termed the fecal ratio-the proportion of pixels identified as feces (F) relative to those identified as mucosal tissue (M) (OSABPS = F/M)-thereby making 0 the optimal score, indicating a perfect cleansing. The Youden J was used to set the threshold because it determines the optimal balance between sensitivity and specificity. The algorithm was then tested on 1405 colonoscopies from 3 hospitals (internal validation) and 5525 frames from a public colonoscopy database (Nerthus, external validation).

RESULTS

Internal validation: the OSABPS correlated significantly with the BBPS (Pearson r = -0.42, P < .001). A threshold of 0.09 OSABPS was determined using the Youden J. The polyp detection rate was higher for colonoscopies below the threshold of the Youden J (2-proportion z-test, P < .001). External validation: the OSABPS correlated significantly with the BBPS (Pearson r = -0.70, P < .001).

CONCLUSIONS

The OSABPS can automatically, instantly, and without human bias assess bowel preparation quality. Colonoscopies with an OSABPS of >0.09 should be considered for reexamination. The OSABPS's open-source nature allows free implementation.

Safety and Efficacy of Polyethylene Glycol Versus Placebo in the Bowel Preparation for Elective Colorectal Surgeries: A Systemic Review and Meta-Analysis

The most suitable type of preoperative colonic preparation for colorectal surgery is controversial. Polyethylene glycol (PEG) has been widely used and some regard it as more suitable for bowel cleansing. However, it also has some limitations, such as nausea and vomiting. These problems have caused surgeons to question whether bowel cleansing offers any benefit at all. This study aims to assess the safety and efficacy of PEG, compare it with other available bowel preparations, conduct a detailed analysis of the available evidence, and inform clinical practice guidelines for bowel preparation before elective colorectal surgeries. MeSH terms and keywords, including "colorectal surgeries", "polyethylene glycol", and "placebo", were used to run a literature search on PubMed, Embase, Cochrane, and Clinicaltrials.gov from inception to January 2025. Randomized controlled trials (RCTs) comparing PEG with placebo for patients undergoing colorectal surgeries were included. Risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using the Mantel-Haenszel method in RevMan (Cochrane Collaboration, London, UK). Random effects meta-analysis was undertaken. Ten RCTs with a total of 2613 patients were included. Polyethylene showed no significant benefits over placebo regarding quality of bowel preparation (RR = 1.03, 95% CI: 0.91-1.17, p = 0.64) and incidence of surgical site infections (SSIs) (RR = 1.29, 95% CI: 0.95-1.75; p = 0.11). Both groups were comparable in terms of anastomotic leak (RR = 1.14, 95% CI: 0.70-1.85, p = 0.60), intra-abdominal abscess (RR = 0.77, 95% CI: 0.36-1.65, p = 0.50), ileus (RR = 1.16, 95% CI: 0.44-3.05, p = 0.76), anastomotic dehiscence (RR = 0.79, 95% CI: 0.39-1.59, p = 0.51), vomiting (RR = 0.54, 95% CI: 0.27-1.09, p = 0.09), and repeated operations (RR = 0.66, 95% CI: 0.20-2.24, p = 0.51). PEG has no significant benefits over placebo for bowel preparation before colorectal surgeries. Further research and RCTs are necessary to identify and explore other therapeutic options for patients undergoing colorectal surgeries.

Efficacy, Safety, and Tolerance of Split Dose Oral Sulfate Solution Versus Split-Dose Polyethylene Glycol Versus Single Dose Polyethylene Glycol for Colonoscopy Preparation: A Prospective Randomized Study

Background

The quality of bowel preparation is one of the key determinants of a successful colonoscopy. Bowel preparation regimens have evolved greatly over the past few decades, with attempts to improve the efficiency and tolerability; still an ideal agent or regimen continues to be oblivious. To compare the efficacy, safety, and tolerance of three bowel preparation regimens for colonoscopy: split dose of oral sulfate solution (OSS), split dose of polyethylene glycol (PEG), and same-day single dose PEG.

Methods

This study was a randomized, single-blind control design with three study groups. Group A received a split dose of OSS, group B received a split dose of PEG, and Group C received a single dose of PEG for bowel preparation. The quality of preparation was assessed using the Boston Bowel Preparation Scale (BBPS), and the adverse effects and tolerance were noted. The data were compared statistically for any significant difference between the regimens.

Results

Mean total BBPS scores were 8.08, 7.52, and 7.92 for groups A, B, and C, respectively (P=0.076). Segmental BBPS scores were statistically similar for the right and transverse colon but differed for the left colon (A: B: C=2.79: 2.54: 2.75; P<0.01). Gastrointestinal side effects and electrolyte disturbances were similar across the three groups. Split-dose preparations were associated with more significant sleep disturbances than single-dose PEG (P<0.001). Patients who received OSS reported more taste intolerance (P<0.01), while those who received single PEG reported more volume intolerance (P<0.001).

Conclusion

Split-dose OSS, split-dose PEG, and single-dose PEG regimens provide adequate and comparable bowel preparation for colonoscopy with good patient tolerance and no significant adverse effects. Overnight PEG and OSS preparations were associated with more substantial sleep disturbances. OSS is associated with more taste intolerance, while single PEG is associated with more volume intolerance.

Effectiveness and safety of polyethylene-glycol-4000 versus sodium picosulphate plus magnesium oxide and citric acid for bowel cleansing before colonoscopy in children: A systematic review with meta-analysis

Colonoscopy is performed for diagnostic and therapeutic purposes. The quality of colonoscopy depends on adequate bowel cleansing. However, there is no standardized protocol for bowel preparation in children. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to estimate the effectiveness, safety, and tolerability profile of polyethylene glycol (PEG) compared with those of sodium picosulfate magnesium citrate (SPMC) in children. The primary sources of the reviewed studies were Scopus, PubMed, and Cochrane Library. The databases were systematically searched for RCTs comparing PEG 4000 to SPMC as a bowel cleansing solution. Six studies were included. The analysis showed that both PEG and SPMC are effective for bowel cleansing, while a split-dose regimen may be preferable to a day-before one. There were no differences between the two groups regarding adverse events (AEs) such as abdominal pain, nausea, vomiting, bloating, and anal discomfort. Additionally, preparation with SPMC was preferred in terms of acceptability and compliance. Still, the need to place a nasogastric tube was significantly lower in the SPMC group compared to the PEG group and in the split dose regimen compared to the day before. In conclusion, PEG and SPMC are equally effective in obtaining an adequate bowel cleansing with a comparable AE rate; moreover, split-dose administration may be preferable to day-before one in terms of effective bowel cleansing. However, SPMC preparation is more acceptable seems to result in higher compliance, and to reduce the use of a nasogastric tube, that we encounter daily in clinical practice, is perceived as a stressful experience for children and their families.

Efficacy and safety of a new low-volume PEG with citrate and simethicone bowel preparation for pediatric elective colonoscopy: Phase 3 RCT

Background and study aims Currently available polyethylene glycol (PEG)-based preparations continue to represent a challenge in children. The aim of this study was to compare the efficacy and safety of a new low-volume PEG preparation with a conventional PEG-electrolyte solution (PEG-ES) in children and adolescents. Patients and methods This was a multicenter, randomized, observer-blind, parallel-group, phase 3 clinical trial, where patients were randomized between PMF104 (Clensia) and a conventional PEG-ES (Klean-Prep), and stratified by age stratum (2 to <6; 6 to < 12;12 to <18 years). The primary endpoint was to test the non-inferiority of PMF104 versus PEG-ES, in terms of colon cleansing. Safety, tolerability, acceptability, palatability, and compliance were also assessed. Efficacy endpoints were analyzed in the per protocol set (PPS) and full analysis set (FAS) and safety and tolerability endpoints in the safety set (SAF). Results Of the 356 patients enrolled, 258 were included in the PPS, 346 in the FAS, and 351 in the SAF. Non-inferiority of PMF104 was confirmed for children aged > 6 years and for all age groups in PPS and FAS, respectively. Optimal compliance was reported more frequently in the PMF104 than in the PEG-ES group, in both PPS (86.1% vs. 68.4%) and FAS (82.9% vs. 65.3%). Both preparations were equally safe and tolerable. Palatability and acceptability were considered better in the PMF104 group than in the PEG-ES group (27.1% vs. 15.3% and 15.3% vs. 3.5%, respectively). Conclusions In children aged 6 to 17 years, the new low-volume product PMF104 is non-inferior to the reference PEG-ES in terms of bowel cleansing, safety, and tolerability, with slightly better results in compliance, palatability, and acceptability.

Comparing Low Volume Versus Conventional Volume of Polyethylene Glycol for Bowel Preparation during Colonoscopy: A Randomised Controlled Trial

BACKGROUND

Polyethylene glycol (PEG) solution is widely used as a colonoscopic bowel cleaning agent, although some patients are intolerant due to the need for ingesting large solution volumes and unpleasant taste. A low-volume solution may enhance patient tolerability and compliance in bowel preparation. Accordingly, this study compared the effectiveness of two difference PEG volumes for bowel preparation before colonoscopy in terms of bowel cleanliness, completeness of colonoscopy, patient tolerability and colonoscopy duration.

METHODS

Using a prospective randomised controlled single-blinded study design, 164 patients scheduled for colonoscopy were allocated to two groups (n = 82 patients in each) to receive either the conventional PEG volume (3 L, control group) or the low volume (2 L, intervention group). The Boston Bowel Preparation Scale (BBPS), a validated scale for assessing bowel cleanliness during colonoscopy, was used to score bowel cleanliness in three colon segments. Secondarily, colonoscopy completeness, tolerability to drinking PEG and the duration of colonoscopy were compared between the groups.

RESULTS

There were no statistically significant differences between the two intervention groups in terms of bowel cleanliness (P = 0.119), colonoscopy completion (P = 0.535), tolerability (P = 0.190) or the amount of sedation/analgesia required (midazolam, P = 0.162; pethidine, P = 0.708). Only the duration of colonoscopy differed between the two groups (longer duration in the control group, P = 0.039).

CONCLUSION

Low-volume (2 L) PEG is as effective as the standard 3 L solution in bowel cleaning before colonoscopy; however, the superiority of either solution could not be established.

Split-dose versus day-before regimen of sodium picosulfate plus magnesium citrate for bowel cleansing before colonoscopy in children: Randomized controlled trial

OBJECTIVES

Polyethylene glycol (PEG) split-dose regimen is recommended as the option of choice for colon preparation before colonoscopy in children and adults. Sodium picosulfate plus magnesium citrate (SPMC) is equally effective but better tolerated than PEG for bowel preparation before colonoscopy in children. The aim of this study was to assess the superiority of SPMC split-dose regimen compared with SPMC day-before regimen for bowel cleansing before colonoscopy in children.

METHODS

This was a multicenter, randomized, single-blind study. Pediatric inpatients undergoing colonoscopy received SPMC either in the day-before dosing or in split dosing. Overall bowel cleansing was assessed using the Boston Bowel Preparation Scale (BBPS) and was rated as successful when BBPS was ≥6. Patient tolerability, acceptability, and compliance were recorded.

RESULTS

The rate of successful cleansing level was significantly higher in the split-dose group than in the day-before group (P < 0.001). The BBPS scores were significantly higher in the split-dose group than in the day-before group for the whole colon (P < 0.001), the right colon (P < 0.001) and transverse colon (P < 0.001). Patient acceptability was better in the split-dose group (P = 0.0003; P = 0.005). The percentage of children needing nasogastric tube placement was better in the split-dose group (P = 0.007).

CONCLUSIONS

The split-dose regimen of SPMC was superior to the day-before regimen in terms of successful colon cleansing and acceptability.

Evaluating the Safety and Quality of Diagnostic Colonoscopies Performed by General Surgeons: A Retrospective Study

Introduction Colonoscopy, which is a challenging procedure and requires adequate time to master the skill, is the procedure of choice to visualize colonic mucosa to rule out many colonic pathologies. There is a dearth of published information from real clinical experiences regarding successful procedures and limitations. The end point of colonoscopy is the visualization of the cecal pole by intubating the cecum. Many Europeans and English health organizations recommend that the procedure should have a completion rate of around or above 90%. Gut preparation is an important determinant for a successful procedure and obviates the need for further invasive and/or expensive procedures such as imaging. The majority of colonoscopies are being performed by gastroenterologists (GI) throughout the world, and the role of a surgeon as an endoscopist is in debate. Before this study, neither a retrospective nor a prospective evaluation of the general surgeon's (GS) endoscopy's quality and safety had been evaluated in our institution. Material and method This retrospective observational study was carried out from 1 January 2022 to 31 August 2022 in the Department of Surgery at Mayo Hospital, Lahore, to evaluate colonoscopy completion rates, reason for failure, and complications in terms of bleeding and perforation. All patients undergoing lower gastrointestinal endoscopy (LGiE), both elective and emergency, were included. Patients under 15 years of age and patients known to be hepatitis B-positive or hepatitis C-positive were excluded from the study. All relevant data were entered into a data sheet. Qualitative variables such as gender, cecal intubation, adjusted cecal intubation, gut preparation, reasons for failed colonoscopy, analgesia use, and complications (bleeding and perforation) were calculated as frequency and percentage. Quantitative data such as age and pain score were reported as mean and standard deviation (SD). Details obtained were tabulated and analyzed via the Statistical Package for Social Sciences (SPSS) version 29.0 (IBM SPSS Statistics, Armonk, NY). Results A total of 57 patient data were collected; 35.1% (n=20) were female, and 64.9% (n=37) were males. The cecal intubation rate (CIR) was 49.1% (n=28), and the adjusted rate was 71.9%, excluding incompleteness due to mass obstructing lumen, 8.8% (n=5); planned left colonoscopy, 7% (n=4); sigmoidoscopy, 3.5% (n=2); distal stoma scope, 1.8% (n=1); and colonic stricture, 1.8% (n=1). The prevalent reason for failed colonoscopy was inadequate gut preparation (15.8% {n=9}). Other reasons include patient discomfort, 3.5% (n=2); looping of scope, 7% (n=4); and acute colonic angulation, 1.8% (n=1). No complications were recorded. Conclusion This study shows that colonoscopy can be done by general surgeons safely and effectively with adequate training. High rates of cecal intubation emerge during colonoscopies performed under deep sedation and by skilled colonoscopists. Adequate bowel preparatory regimen is compulsory for quality procedure.

Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

Use of Simethicone After Capsule Ingestion and Its Impact on the Quality of Small Bowel Video Capsule Endoscopy: A Pilot Study

Background Small bowel capsule endoscopy is a tool to visualize the small bowel (SB) for conditions such as obscure bleeding. Various studies have been performed to compare various bowel preparation regimens in terms of small bowel transit time (SBTT), small bowel visualization quality (SBVQ), and diagnostic yield (DY). Literature suggests that using polyethylene glycol (PEG) prep is significantly better compared to clear liquid and overnight fast in terms of SBVQ and DY. Other investigators have tried to assess the efficacy of adding simethicone to the bowel preparation regimen which seems to improve SBVQ. However, no studies have been done to assess the results of simethicone ingestion after capsule swallowing. We intend to give patients simethicone one hour after capsule ingestion for two consecutive hours and compare results for SBVQ pre-and post-ingestion groups. The objective of this study is to compare the effect of simethicone on SBVQ in pre- and post-capsule ingestion groups. Methodology This prospective, randomized controlled trial included patients who were scheduled for outpatient capsule endoscopy at Albany Medical Center (AMC) Endoscopy Suite. Patients were divided into the control group, group 1, and the treatment group (group 2). The control group followed the standard AMC pre-capsule protocol that included PEG 238 g the evening prior. Group 1 included patients who received 3 mL of simethicone (20 mg/0.3 mL) 20 minutes prior to ingesting the capsule. The treatment group (group 2) included patients who ingested simethicone 3 mL 20 minutes prior to capsule swallowing, 3 mL after one hour, and 1.5 mL after another hour, totaling 7.5 mL of simethicone. Data regarding SBVQ for every patient were evaluated as an individual zone score from 1-3 points, each in proximal, middle, and distal SB based on the SBTT. A cumulative score of 3-9 was given after adding the three zones. These scores were derived using the Boston Bowel Preparation Scale. Data analysis was done using Microsoft Excel software. Results There were six patients in the control group, eight in group 1, and eight in the treatment group (group 2). Proximal, middle, and distal SB did not show any significant difference between their SBVQ scores. Moreover, the total combined score also showed no statistical difference in the SBVQ score. Conclusions There were no statistically significant differences in the SBVQ neither while looking at the cumulative score nor individual segmental score of the entire SB. However, this is only a pilot project with a small number of subjects and results may differ in future studies with increased power.

The Influence of Mechanical Bowel Preparation on Volatile Organic Compounds for the Detection of Gastrointestinal Disease-A Systematic Review

(1) Background: Colorectal cancer is the second commonest cause of cancer deaths worldwide; recently, volatile organic compounds (VOCs) have been proposed as potential biomarkers of this disease. In this paper, we aim to identify and review the available literature on the influence of mechanical bowel preparation on VOC production and measurement. (2) Methods: A systematic search for studies was carried out for articles relevant to mechanical bowel preparation and its effects on volatile organic compounds. A total of 4 of 1349 papers initially derived from the search were selected. (3) Results: Two studies with a total of 134 patients found no difference in measured breath VOC profiles after bowel preparation; one other study found an increase in breath acetone in 61 patients after bowel preparation, but no other compounds were affected. Finally, the last study showed the alteration of urinary VOC profiles. (4) Conclusions: There is limited data on the effect of bowel preparation on VOC production in the body. As further studies of VOCs are conducted in patients with symptoms of gastrointestinal disease, the quantification of the effect of bowel preparation on their abundance is required.

Low-dose of magnesium sulfate solution was not inferior to standard regime of polyethylene glycol for bowel preparation in elderly patients: a randomized, controlled study

BACKGROUND

Large polyethylene glycol (PEG) is a standard regimen for bowel preparation. However, elderly patients suffered from adverse events. This study was to compare the efficacy and safety of oral magnesium sulfate solution (MSS) vs standard PEG in elderly patients undergoing colonoscopy.

METHODS

Elderly patients aged 60-90 years, from two endoscopic centers, were enrolled in China. Patients were randomized to take a low dose of MSS or a standard PEG regime in a split-dose regime. The primary endpoint was the proportion of patients with adequate bowel preparation, which was defined as the total Boston Bowel Preparation Scale (BBPS) ≥6 and each segmental BBPS was ≥2. Secondary outcomes included adenoma detection rate (ADR), safety, adverse events, cecal intubation rate, willingness to repeat BP, and so on.

RESULTS

1174 elderly patients were randomly allocated to the MSS group (n = 588) or the standard group (n = 586). Adequate BP was achieved in 94.0% of patients in the MSS group and 92.5% in the control (p = .287). ADR was also comparable between the two groups (43.0% and 39.9%, p = .282). Compared with the standard group, MSS group reported less abdominal discomfort (1.7% vs 6.0%), less nausea (13.6% vs 21.0%) and vomiting (1.2% vs 4.2%). The change in serum potassium levels after preparation in the standard group was significantly lower than that in the MSS group (-0.19 ± 0.08 vs -0.41 ± 0.11, p = .037).

CONCLUSIONS

Low dose of MSS was not inferior to the standard PEG regime in terms of bowel preparation quality for elderly patients. Low-dose MSS offered fewer adverse events and better tolerability. It is a preferable choice for the elderly to undergo bowel preparation for colonoscopy.

CLINICAL TRIAL REGISTRATION NUMBER

NCT04948567.

SPLIT-DOSE BOWEL PREPARATION IS SUPERIOR TO STRAIGHT-DOSE IN HOSPITALIZED PATIENTS UNDERGOING INPATIENT COLONOSCOPY

BACKGROUND

There is a two-fold higher rate of failed colonoscopy secondary to inadequate bowel preparation among hospitalized versus ambulatory patients. Split-dose bowel preparation is widely used in the outpatient setting but has not been generally adapted for use among the inpatient population.

OBJECTIVE

The aim of this study is to evaluate the effectiveness of split versus single dose polyethylene glycol bowel (PEG) preparation for inpatient colonoscopies and determine additional procedural and patient characteristics that drive inpatient colonoscopy quality.

METHODS

A retrospective cohort study was performed on 189 patients who underwent inpatient colonoscopy and received 4 liters PEG as either split- or straight-dose during a 6-month period in 2017 at an academic medical center. Bowel preparation quality was assessed using Boston Bowel Preparation Score (BBPS), Aronchick Score, and reported adequacy of preparation.

RESULTS

Bowel preparation was reported as adequate in 89% of the split-dose group versus 66% in the straight-dose group (P=0.0003). Inadequate bowel preparations were documented in 34.2% of the single-dose group and 10.7% of the split-dose group (P<0.001). Only 40% of patients received split-dose PEG. Mean BBPS was significantly lower in the straight-dose group (Total: 6.32 vs 7.73, P<0.001).

CONCLUSION

Split-dose bowel preparation is superior to straight-dose preparation across reportable quality metrics for non-screening colonoscopies and was readily performed in the inpatient setting. Interventions should be targeted at shifting the culture of gastroenterologist prescribing practices towards use of split-dose bowel preparation for inpatient colonoscopy.

A multicenter randomized phase 4 trial comparing sodium picosulphate plus magnesium citrate vs. polyethylene glycol plus ascorbic acid for bowel preparation before colonoscopy. The PRECOL trial

BACKGROUND

Adequate bowel preparation before colonoscopy is crucial. Unfortunately, 25% of colonoscopies have inadequate bowel cleansing. From a patient perspective, bowel preparation is the main obstacle to colonoscopy. Several low-volume bowel preparations have been formulated to provide more tolerable purgative solutions without loss of efficacy.

OBJECTIVES

Investigate efficacy, safety, and tolerability of Sodium Picosulphate plus Magnesium Citrate (SPMC) vs. Polyethylene Glycol plus Ascorbic Acid (PEG-ASC) solutions in patients undergoing diagnostic colonoscopy.

MATERIALS AND METHODS

In this phase 4, randomized, multicenter, two-arm trial, adult outpatients received either SPMC or PEG-ASC for bowel preparation before colonoscopy. The primary aims were quality of bowel cleansing (primary endpoint scored according to Boston Bowel Preparation Scale) and patient acceptance (measured with six visual analogue scales). The study was open for treatment assignment and blinded for primary endpoint assessment. This was done independently with videotaped colonoscopies reviewed by two endoscopists unaware of study arms. A sample size of 525 patients was calculated to recognize a difference of 10% in the proportion of successes between the arms with a two-sided alpha error of 0.05 and 90% statistical power.

RESULTS

Overall 550 subjects (279 assigned to PEG-ASC and 271 assigned to SPMC) represented the analysis population. There was no statistically significant difference in success rate according to BBPS: 94.4% with PEG-ASC and 95.7% with SPMC (P = 0.49). Acceptance and willing to repeat colonoscopy were significantly better for SPMC with all the scales. Compliance was less than full in 6.6 and 9.9% of cases with PEG-ASC and SPMC, respectively (P = 0.17). Nausea and meteorism were significantly more bothersome with PEG-ASC than SPMC. There were no serious adverse events in either group.

CONCLUSION

SPMC and PEG-ASC are not different in terms of efficacy, but SPMC is better tolerated than PEG-ASC. SPMC could be an alternative to low-volume PEG based purgative solutions for bowel preparation.

CLINICAL TRIAL REGISTRATION

[ClinicalTrials.gov], Identifier [NCT01649674 and EudraCT 2011-000587-10].

Evaluation of the efficacy of 1 L polyethylene glycol plus ascorbic acid and an oral sodium sulfate solution: A multi-center, prospective randomized controlled trial

INTRODUCTION

Low-volume bowel preparation has been developed to increase patient compliance. We compared 1 L of polyethylene glycol/ascorbic acid (PEG/Asc) and oral sodium sulfate (OSS) with respect to bowel preparation efficacy, compliance, and safety.

METHODS

A multicenter, prospective, randomized, single-blinded, non-inferiority trial was conducted in 3 hospitals. Patients were randomized to receive a bowel-cleansing agent. Bowel-cleansing efficacy was evaluated using the Boston Bowel Preparation Scale (BBPS). Satisfaction, feeling, taste of the bowel cleanser, and adverse events after taking the bowel cleanser were investigated through a questionnaire. Additionally, blood samples were analyzed before and after bowel cleansing.

RESULTS

In total, 172 patients were analyzed (85 with 1 L PEG/Asc and 87 with OSS), and the mean BBPS scores were comparable between agents. The 1L PEG/Asc group tended to have a higher BBPS score in the right colon (2.22 vs 2.02; P = .08). The compliance of 1 L of PEG/Asc was comparable to that of OSS. Patients taking 1 L PEG/Asc reported greater thirst and dizziness (P = .04 and P = .047, respectively) than the OSS cohort. On the other hand, gastrointestinal symptoms such as vomiting and abdominal distension were more common in the OSS group, without statistical significance. In terms of laboratory adverse events, elevation of serum creatinine was found in both groups after taking the bowel cleansing agent (P < .001 for the 1L PEG/Asc group; P = .04 for the OSS group). However, most of the increased values were within the normal ranges.

DISCUSSION

The 1L PEG/Asc treatment was comparable to OSS in terms of bowel preparation efficacy, compliance, and safety.

Evidence-based considerations on bowel preparation for colonoscopy

We recently read with interest the article, "Novel frontiers of agents for bowel cleansing for colonoscopy". This is a practical narrative review, which could be of particular importance to clinicians in order to improve their current practice. Although we appreciate the venture of our colleagues, based on our in-depth analysis, we came across several minor issues in the article; hence, we present our comments in this letter. If the authors consider these comments further in their relevant research, we believe that their contribution would be of considerable importance for future studies.

Artificial Intelligence and the Future of Gastroenterology and Hepatology

The integration of artificial intelligence (AI) into gastroenterology and hepatology (GI) will inevitably transform the practice of GI in the coming decade. While the application of AI in health care is not new, advancements are occurring rapidly, and the future landscape of AI is beginning to come into focus. From endoscopic assistance via computer vision technology to the predictive capabilities of the vast information contained in the electronic health records, AI promises to optimize and expedite clinical and procedural practice and research in GI. The extensive body of literature already available on AI applications in gastroenterology may seem daunting at first; however, this review aims to provide a breakdown of the key studies conducted thus far and demonstrate the many potential ways this technology may impact the field. This review will also take a look into the future and imagine how GI can be transformed over the coming years, as well as potential limitations and pitfalls that must be overcome to realize this future.

Efficacy and Safety of TJP-008 Compared to 2 L PEG with Ascorbate in Colon Cleansing: A Randomized Phase 3 Trial

Background/Aims

Polyethylene glycol (PEG)-based bowel preparations are effective cleansing agents for colonoscopy. However, they require relatively large volumes to be used even with agents such as 2 L PEG with ascorbate (2LPEG). This phase 3, randomized, single-blinded, multicenter, parallel-group study compared the efficacy of 1 L PEG with high-dose ascorbate, TJP-008, to 2LPEG.

Methods

Patients undergoing colonoscopy were randomized (111) to receive TJP-008 as 1-day split dose (TJP-008-1) or 2-day split dose (TJP-008-2) regimen or to receive 2LPEG as a 2-day split dose regimen. Cleansing efficacy was evaluated using the Harefield Cleansing Scale. The primary endpoint was overall bowel cleansing success. Full analysis set (FAS) and per protocol set (PPS) analyses were performed.

Results

Of the 314 screened patients, efficacy was assessed in the following patient numbers (FAS/PPS) total (293/285), TJP-008-1 (98/94), TJP-008-2 (97/95), and 2LPEG (98/96). FAS revealed noninferiority between TJP-008 and 2LPEG with regard to overall success (TJP-008-2, 99.0%; TJP-008-1, 95.9%; 2LPEG, 94.9%; p=0.100 and p=0.733, respectively). PPS also showed noninferiority (p=0.721 and p=0.211, respectively). However, the PPS analyses showed a higher bowel cleansing score for TJP-008-2 for high-quality cleansing in the right colon (TJP-008-2 83.2% vs 2LPEG 62.5%; p=0.005).

Conclusions

TJP-008 is a new low-volume cleansing agent with a colon cleansing efficacy comparable to that of standard 2LPEG that exhibits significant safety and tolerability.

Randomized clinical trial: efficacy and tolerability of two different split dose of low-volume polyethylene glycol electrolytes for bowel preparation before colonoscopy in hospitalized children

BACKGROUND

Eighty milliliter per kilogram of polyethylene glycol (PEG) for bowel preparation (BP) has been recommended, but the amount of liquid orally without nasogastric intubation is difficult to achieve. This study is to compare the efficacy and tolerability of two different low-volume PEG electrolyte solutions for BP in children.

METHODS

The randomized, double-blind, controlled trial enrolled 150 children aged 6-18 years undergoing colonoscopy in our center. Patients were randomly assigned to receive 60 ml/kg (PEG-ELS 60) or 40 ml/kg (PEG-ELS 40) of PEG electrolytes (PEG-ELS) 4000. The Boston Bowel Preparation Scale was used for bowel cleansing evaluation. Primary end point was overall colon cleansing. Tolerability was also evaluated.

RESULTS

PEG-ELS 40 and PEG-ELS 60 had similar efficacy in bowel cleansing for both whole colon and various colonic segments. The proportions of patients experiencing any adverse symptoms, or those who were willing to have BP repeated if necessary were similar in both groups. More patients considered the BP solution easy to take and be satisfied with the preparation in PEG-ELS 40 than PEG-ELS 60.

CONCLUSIONS

Low volume of PEG-ELS for BP has good efficacy in bowel cleansing. PEG-ELS with 40 ml/kg volume was not inferior to that of 60 ml/kg.

IMPACT

PEG-ELS 40 and PEG-ELS 60 had similar efficacy in bowel cleansing for whole and various colonic segments. The proportions of patients experiencing any adverse symptoms, or those who were willing to have BP repeated if necessary were similar in both groups. More patients considered BP solution easy to take and be satisfied with the preparation in PEG-ELS 40 than PEG-ELS 60. This study showed that low-volume PEG-ELS monotherapy was effective in bowel cleansing and explored a possibly feasible BP method for pediatrics in China that PEG-ELS 40 was comparable to PEG-ELS 60 regimen.

Cleansing efficacy and safety of bowel preparation protocol using sodium picosulfate/magnesium citrate considering subjective experiences: An observational study

BACKGROUND

Research data from patient reports indicate that the least bearable part of colonoscopy is the administration of laxatives for bowel preparation.

AIM

To observe the intestinal cleansing efficacy and safety of sodium picosulfate/magnesium citrate and to discuss the patients’ experiences due to the procedure.

METHODS

Subjects hospitalized in the International Medical Center Ward of Peking University International Hospital, Beijing, China, from April 29 to October 29, 2020, for whom the colonoscopy was planned, were enrolled. Bowel preparation was performed using sodium picosulfate/magnesium citrate. The effect of bowel cleansing was evaluated according to the Ottawa Bowel Preparation Scale, defecation conditions and adverse reactions were recorded, and the comfort level and subjective satisfaction concerning medication were evaluated by the visual analogue scale/score (VAS).

RESULTS

The bowel preparation procedure was planned for all patients enrolled, which included 42 males and 22 females. The results showed an average liquid rehydration volume of 3000 mL, an average onset of action for the first dose at 89.04 min, an average number of bowel movements of 4.3 following the first dose, an average onset of action for the second dose at 38.90 min and an average number of bowel movements of 5.0 after the second dose. The total average Ottawa Bowel Preparation Scale score was 3.6, with 93.55% of bowel preparations in the “qualified” and 67.74% in the “excellent” grade. The average VAS score of effect on sleep was 0, and the average VAS score of perianal pain was also 0. The average VAS score for ease of taking and taste perception of the bowel cleanser was 10. Side effects included mild to moderate nausea (15.63%), mild vomiting (4.69%), mild to moderate abdominal pain (7.81%), mild to moderate abdominal distension (20.31%), mild palpitation (7.81%) and mild dizziness (4.69%).

CONCLUSION

Sodium picosulfate/magnesium citrate is effective and safe for bowel preparation before colonoscopy with high subjective patient acceptance, thus improving overall patient compliance.

Quality Control in the Slovenian National Colorectal Cancer Screening Program

OBJECTIVES

The objective of the study was to assess the impact of an internal quality indicator (QI) audit on the quality level of colonoscopies in the National Colorectal Cancer Screening Program (NCCSP).

DESIGN

Sixty-eight colonoscopists from 29 endoscopic centres participated in the NCCSP from April 2009 to January 2015. Controlled QIs were the percentage of total colonoscopies, adenoma detection rate (ADR), mean adenoma per procedure (MAP), mean adenoma per positive procedure (MAP+), right-sided ADR, sessile serrated lesion (SSL) detection rate, and patient responses to post-procedural questionnaires. A group of 3 expert endoscopists from the NCCSP Council performed 91 inspections and provided education.

RESULTS

A total of 891.364 (58.2%) Slovenian citizens participated in the first 3 screening rounds of the NCCSP. Among 46.552 (6%) positive individuals, 42.866 (92.1%) underwent first colonoscopies. Total colonoscopies were performed in 98% of endoscopies (p = 0.459 between cycles), mean ADR was 51.8% (p = 0.872 between cycles), mean percentage of adenoma in the right colon was 37.5% (p = 0.227 between cycles), mean MAP was 1.1 (p = 0.981 between cycles), mean MAP+ was 2.0 (p = 0.824 between cycles), and mean SSL detection rate was 3% (p < 0.001). We observed great difference in QIs between endoscopists and a significant increase in MAP, ADR in the right colon, and SSL per endoscopist during the 6-year period. Due to quality underperformance, 3 endoscopic centres (10.3%) and 13 endoscopists (19.1%) were excluded from the program.

CONCLUSIONS

The success of the NCCSP is related to the quality of colonoscopies performed. To ensure the proper quality level, regular audit and permanent education are needed.

Prospective single-blinded single-center randomized controlled trial of Prep Kit-C and Moviprep: Does underlying inflammatory bowel disease impact tolerability and efficacy?

BACKGROUND

Colonoscopy remains the gold standard for detection of colonic disease. An optimal evaluation depends on adequate bowel cleansing. Patients with inflammatory bowel disease (IBD), require frequent endoscopic assessment for both activity and dysplasia assessment. Two commonly used bowel preparations in Australia are Prep Kit-C (Pc) and Moviprep (Mp). Little is known about tolerability, efficacy and safety of split protocols of Mp and Pc in both IBD and non-IBD patients.

AIM

To primary aim was to compare the tolerability, efficacy and safety of split protocols of Mp and Pc in patients having a colonoscopy. The secondary aim was to compare the efficacy, tolerability and safety of either preparation in patients with or without IBD.

METHODS

Patients were randomized to Pc or Mp bowel preparation. Patients completed a questionnaire to assess tolerability. Efficacy was assessed using the Ottawa Bowel Preparation Score. Serum electrolytes and renal function were collected one week prior to colonoscopy and on the day of colonoscopy.

RESULTS

Of 338 patients met the inclusion criteria. Of 168 patients randomized to Mp and 170 to Pc. The efficacy of bowel preparation (mean Ottawa Bowel Preparation Score) was similar between Mp (5.4 ± 2.4) and Pc (5.1 ± 2.1) (P = 0.3). Mean tolerability scores were similar in Mp (11.84 ± 5.4) and Pc (10.99 ± 5.2; P = 0.17). 125 patients had IBD (73 had Crohn’s Disease and 52 had Ulcerative colitis). Sixty-four IBD patients were allocated to Mp and 61 to Pc. In non-IBD patients, 104 were allocated to Mp and 109 to Pc. The mean tolerability score in the IBD group was lower than the non-IBD group (mean tolerability scores: IBD: 10.3 ± 5.1 and non-IBD: 12.0 ± 5.3; P = 0.01). IBD patients described more abdominal pain with Mp when compared with Pc; (Mp: 5.7 ± 4.4 vs Pc: 3.6 ± 2.6, P = 0.046). Serum magnesium level increased with Pc compared with Mp in all patients (mean increase in mmol/L: Mp: 0.03 ± 0.117 and Pc: 0.11 ± 0.106; P < 0.0001).

CONCLUSION

In this study, the efficacy, tolerability and safety of Mp and Pc were similar in all patients. However, patients with IBD reported lower tolerability with both preparations. Specifically, IBD patients had more abdominal pain with Mp. These results should be considered when recommending bowel preparation especially to IBD patients.

Involvement of estrogen in phosphorus-induced nephrocalcinosis through fibroblast growth factor 23

Excessive phosphorus intake adversely affects bone and mineral metabolism. Estrogen is one of the factors affecting fibroblast growth factor 23 (FGF23), a phosphorus-regulating hormone. However, the interaction between excess phosphorus and estrogen status has not been fully elucidated. This study investigated the involvement of estrogen in the effects of high phosphorus intake on bone metabolism and ectopic calcification in ovariectomized (OVX) rats. The interaction between high phosphorus diet and OVX was not observed in bone mineral density and aortic calcium. In contrast, high phosphorus intake markedly increased renal calcium concentration in sham rats, whereas the effect was attenuated in OVX rats, which was reversed by a selective estrogen-receptor modulator treatment. A strong positive correlation between renal calcium and serum FGF23 was observed. In addition, fibroblast growth factor receptor 1 (FGFR1: a predominant receptor of FGF23) inhibitor treatment partially decreased renal calcium concentrations in rats with high phosphorus intake. In conclusion, the effect of high phosphorus intake on bone metabolism and aortic calcification did not depend on the estrogen status; in contrast, high phosphorus intake synergistically induced nephrocalcinosis in the presence of estrogenic action on the bone. Furthermore, FGF23 was involved in the nephrocalcinosis induced by high phosphorus intake partially through FGFR1 signaling.

A novel artificial intelligence system for the assessment of bowel preparation (with video)

BACKGROUND AND AIMS

The quality of bowel preparation is an important factor that can affect the effectiveness of a colonoscopy. Several tools, such as the Boston Bowel Preparation Scale (BBPS) and Ottawa Bowel Preparation Scale, have been developed to evaluate bowel preparation. However, understanding the differences between evaluation methods and consistently applying them can be challenging for endoscopists. There are also subjective biases and differences among endoscopists. Therefore, this study aimed to develop a novel, objective, and stable method for the assessment of bowel preparation through artificial intelligence.

METHODS

We used a deep convolutional neural network to develop this novel system. First, we retrospectively collected colonoscopy images to train the system and then compared its performance with endoscopists via a human-machine contest. Then, we applied this model to colonoscopy videos and developed a system named ENDOANGEL to provide bowel preparation scores every 30 seconds and to show the cumulative ratio of frames for each score during the withdrawal phase of the colonoscopy.

RESULTS

ENDOANGEL achieved 93.33% accuracy in the human-machine contest with 120 images, which was better than that of all endoscopists. Moreover, ENDOANGEL achieved 80.00% accuracy among 100 images with bubbles. In 20 colonoscopy videos, accuracy was 89.04%, and ENDOANGEL continuously showed the accumulated percentage of the images for different BBPS scores during the withdrawal phase and prompted us for bowel preparation scores every 30 seconds.

CONCLUSIONS

We provided a novel and more accurate evaluation method for bowel preparation and developed an objective and stable system-ENDOANGEL-that could be applied reliably and steadily in clinical settings.

Predictive factors for inadequate bowel preparation using low-volume polyethylene glycol (PEG) plus ascorbic acid for an outpatient colonoscopy

Low-volume polyethylene glycol (PEG) plus ascorbic acid solutions are widely used for bowel cleansing before colonoscopy. This study aimed to investigate the pre-endoscopic predictive factors for inadequate preparation in subjects receiving low-volume PEG plus ascorbic acid. A prospective study was performed at Gangnam Severance Hospital, Korea, from June 2016 to December 2016. All participants received low-volume PEG plus ascorbic acid solutions for outpatient colonoscopy. The split-dose bowel preparation was administered in subject with morning colonoscopy while same day bowel preparation was used for afternoon colonoscopy. 715 patients were enrolled (mean age 56.1 years, 54.4% male), of which 138 (19.3%) had an inadequate bowel preparation. In multivariable analysis, cirrhosis (OR 4.943, 95% CI 1.191–20.515), low (less than 70%) compliance for three-day low-residual diet (OR 2.165, 95% CI 1.333–3.515), brown liquid rectal effluent (compared with clear or semi-clear effluent) (OR 7.604, 95% CI, 1.760–32.857), and longer time interval (≥2 hours) between last defecation and colonoscopic examination (OR 1.841, 95% CI, 1.190–2.849) were found as an independent predictors for inadequate preparation. These predictive factors may be useful in guiding additional intervention to improve quality of bowel preparation.

Randomized clinical trial evaluating the effect of a visual educational leaflet on the preparation of colonoscopies in hospitalized patients

BACKGROUND

the safety and diagnostic accuracy of colonoscopies depends on the quality of colon cleansing. Several factors have been reported that affect the quality of bowel cleansing, hospitalization being one of them.

AIMS

the aim of the study was to investigate whether a visual educational leaflet improved the level of cleanliness achieved in hospitalized patients undergoing a colonoscopy and to identify predictors of a poor bowel preparation.

METHODS

a prospective, single-center, endoscopist-blinded, randomized controlled trial was performed. The intervention group was given a visual educational leaflet and both groups received four liters of polyethylene glycol solution. Demographic data, personal history, reason for admission and indication for colonoscopy, work shift during which the procedure was performed and endoscopy findings were collected. The Boston Bowel Preparation Scale (BBPS) was used to assess the bowel preparation.

RESULTS

one hundred and thirty-six patients were included in the study; 51.5% were male, with a mean age of 64.3 ± 17.6 years. The educational leaflet did not result in a difference in the total BBPS obtained between the standard group and the intervention group (7 [6-9] vs 6 [5.7-9]; p = 0.17). According to the multivariable analysis, the only factors associated with a poor bowel cleansing were heart disease (OR 3.37 [1.34-8.46]; p = 0.010) and colorectal cancer (OR 3.82 [1.26-11.61]; p = 0.018).

CONCLUSION

the use of a visual educational leaflet for the preparation of colonoscopies did not provide a significant improvement in hospitalized patients in our health area. Heart disease was identified as the only predictor of poor preparation for colonoscopy.

Split dose versus full single-dose regimen of polyethylene glycol for bowel preparation in pediatric colonoscopy: a pilot study of randomized controlled trial

OBJECTIVES

Previous meta-analyses in adults comparing a full single dose vs. split doses of polyethylene glycol with electrolyte solution demonstrated that the split-dose group had a higher rate of successful bowel preparation. To date, no similar study in children has been conducted. Therefore, we compared the efficacy of bowel preparation between the two regimens of polyethylene glycol with electrolyte solution in pediatric colonoscopy. The secondary outcomes were tolerability, acceptability, and compliance.

METHODS

An investigator-blinded randomized controlled trial was conducted to enroll children aged 2-18 years who underwent an elective colonoscopy at a teaching hospital between March 2018 and February 2019. Patients were randomly assigned to receive polyethylene glycol with electrolyte solution as a full single dose or two split doses. The Boston Bowel Preparation Scale was used for the efficacy (i.e. successful bowel preparation if score ≥ 6). Secondary outcomes were evaluated by using a standardized questionnaire.

RESULTS

A total of 45 colonoscopies (22 in the full single-dose and 23 in the split-dose group) were performed. Mean age was 9.2 years old (SD 4.4). We noted a higher rate of successful bowel preparation in the split-dose group (95% vs. 72%, P = 0.047). Significant higher rate of willingness to repeat the same protocol (83% vs. 36%, P = 0.002) and a trend of lower rate of nausea/vomiting (39% vs. 68%, P = 0.051) in the split-dose group were found.

CONCLUSION

The split-dose regimen of polyethylene glycol with electrolyte solution for bowel preparation suggests superior efficacy, potential tolerability, and acceptability as compared to the traditional full single-dose regimen.

Efficacy, Tolerability, and Safety of Low-Volume Bowel Preparations for Patients with Inflammatory Bowel Diseases: The French Multicentre CLEAN Study

BACKGROUND

Standard high-volume polyethylene glycol [PEG] bowel preparations [PEG-4L] are recommended for patients with inflammatory bowel disease [IBD] undergoing colonoscopy. However, low-volume preparations [≤2 L of active volume] are often used in clinical practice. The aim of this study was to evaluate the efficacy, tolerability, and safety of the various bowel preparations for patients with IBD, including low-volume preparations.

METHODS

We conducted a French prospective multicentre observational study over a period of 1 month. Patients aged 18-75 years with IBD with an indication of colonoscopy independent of the study were enrolled. The choice of the preparation was left to the investigators, as per their usual protocol. The patients' characteristics, disease, and colonoscopy characteristics were recorded, and they were given self-reported questionnaires.

RESULTS

Twenty-five public and private hospitals enrolled 278 patients. Among them, 46 had a disease flare and 41 had bowel stenoses. Bowel preparations for colonoscopy were as follows: 42% received PEG-2L, 29% received sodium picosulfate [Pico], 15% received PEG-4L, and 14% had other preparations. The preparation did not reach the Boston's score efficacy outcome in the PEG-4L group in 51.2% of the patients [p = 0.0011]. The preparation intake was complete for 59.5% in the PEG-4L group, compared with 82.9% in the PEG-2L group and 93.8% in the Pico group [p < 0.0001]. Tolerability, as assessed by the patients' VAS, was significantly better for both Pico and PEG-2L compared with PEG-4L, and better for Pico compared with PEG-2L [p = 0.008; p = 0.0003]. In multivariate analyses, low-volume preparations were independent factors of efficacy and tolerability. Adverse events occurred in 4.3% of the patients.

CONCLUSIONS

Preparations with PEG-2L and Pico were equally safe, with better efficacy and tolerability outcomes compared with PEG-4L preparations. The best efficacy/tolerance/safety profile was achieved with the Pico preparation.

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.

How to improve the adenoma detection rate in colorectal cancer screening? Clinical factors and technological advancements

INTRODUCTION

Colonoscopy has been widely regarded as the gold standard in colorectal cancer (CRC) screening. Within recent years different endoscopic imaging techniques have been introduced to improve the quality of colonoscopy. The adenoma detection rate (ADR) is the single most important quality indicator for colonoscopy. The aim of this study was to evaluate the quality of CRC screening expressed by ADR in two different eras of endoscopic technology advancement.

MATERIAL AND METHODS

We conducted a dual-center study that enrolled 24 055 patients, who underwent colonoscopy as part of a national screening program. Patients were sorted into two groups according to the advancement of endoscopic equipment used for colonoscopic examination: group I - 10 405 patients examined between 2004 and 2008 (standard electronic endoscopes); group II - 13 650 patients examined between 2009 and 2014 (modern endoscopes). The ADR in two different eras and the impact of endoscopic novelties were determined.

RESULTS

The ADR in group I was 29.14%, in group II 31.73% (p < 0.001). The overall ADR was 30.88% - 38.80% and 25.95% (p < 0.001) for the male and female patients, respectively. The mean adenoma number per colonoscopy was 0.366 (95% CI: 0.357-0.375; p < 0.001), 0.337 (0.321-0.352) and 0.380 (0.369-0.392) for patients in group I and group II, respectively.

CONCLUSIONS

Our study shows that technological innovation, novel endoscopy devices and diagnostic techniques improve the quality in CRC screening by increasing the ADR. However, we need to determine which of the technologies are supreme to achieve excellence in colorectal cancer screening.

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.

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.

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.

Comparative safety of bowel cleansers: protocol for a systematic review and network meta-analysis

INTRODUCTION

The US Food and Drug Administration has withdrawn the bowel cleansing kit HalfLytely (PEG 3500) with 10 mg bisacodyl tablets due to an increased risk of ischaemic colitis compared with the same kit with only 5 mg bisacodyl. This is of interest in Canada given that the bowel cleansing kit Bi-Peglyte (PEG 3500) with 15 mg bisacodyl is currently approved for use. The objective is to assess the comparative safety of various bowel cleansers with or without bisacodyl, with a primary interest inpolyethylene glycol (PEG)-based and sodium-picosulfate-based products.

METHODS AND ANALYSIS

Given the existing volume of the literature, the review will be conducted in two stages. Stage 1 will consist of a scoping exercise by searching MEDLINE, Embase and the Cochrane Library (up to 21 November 2017) to identify randomised controlled trials, quasirandomised studies and non-randomised studies in which any bowel cleanser regimens were compared among persons undergoing colonoscopy. The outcomes will be mapped to establish a listing of the studies and their comparisons and outcomes currently available in the literature. From this, a data synthesis plan will be determined. In stage 2, a systematic review with meta-analyses will be pursued, focused on the bowel cleanser comparisons and outcomes of interest identified in stage 1. Two reviewers will screen, extract and quality assess the articles. Outcomes of interest include ischaemic colitis, electrolyte imbalances and their consequences, seizures, bowel perforation and patient tolerability. If sufficient data exist and studies are of sufficient homogeneity, network meta-analyses (NMAs) will be performed.

ETHICS AND DISSEMINATION

Ethics approval was not necessary due to study design. Updating the safety profile of bowel cleansers among the generally healthy population undergoing colonoscopy is pertinent given recent approval changes. This will be the first NMA within this population. Policy considerations may be reconsidered to minimise risk during bowel cleanser use.

PROSPERO REGISTRATION NUMBER

CRD42018084720.

The safety and effectiveness of 2-liter polyethylene glycol plus ascorbic acid in patients with liver cirrhosis: A retrospective observational study

The safety of bowel-cleansing agents is an important issue in clinical practice, especially in patients with chronic diseases. Although the safety and efficacy of polyethylene glycol (PEG) has been investigated in many studies, few studies on PEG plus ascorbic acid exist. In this study, we compared the safety of 2 bowel-cleansing agents for patients with liver cirrhosis: 2-liter PEG (2 L PEG) plus ascorbic acid versus 4-liter PEG (4 L PEG). We performed a retrospective study on colonoscopy in patients with liver cirrhosis. Patients referred for colonoscopy were divided into 2 groups: 2 L PEG plus ascorbic acid (n = 105) and 4 L PEG (n = 61). Safety was assessed by comparing the clinical factors and laboratory findings as follows: blood biochemistry, electrolytes, weight change, and bowel-cleansing quality. Serum electrolytes, laboratory findings, and body weight showed no significant change between the 2 groups. There was no significant change in clinical factors before and after bowel preparation in the PEG group or the PEG plus ascorbic acid group. The acceptability and compliance of patients was better in the 2 L PEG plus ascorbic acid than the 4 L PEG group. In subgroup analysis, patients with compensated or decompensated cirrhosis showed no increased risk of electrolyte imbalances after bowel preparation. Child-Pugh scores did not influence the outcome after bowel cleansing. Successful cleansing was mostly achieved in both groups. Our analysis showed that of the use of 2 L PEG plus ascorbic acid could be a safe choice for colonoscopy in patients with liver cirrhosis.

Results of the FIT-based National Colorectal Cancer Screening Program in Slovenia

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies in the western world.

OBJECTIVE

We aimed to assess the first round of fecal immunochemical test (FIT)-based National CRC screening program (NCSP).

METHODS

In the NCSP conducted in Slovenia, a FIT and colonoscopy for those tested positive was used. The NCSP central unit sent 536,709 invitations to Slovenian residents age 50 to 69 years old between 2009 and 2011. The adherence rate was 56.9% (303,343 participants). FIT was positive in 6.2% (15,310) of the participants (men, 7.8%; women, 5.0%; P<0.01). A total of 13,919 unsedated colonoscopies were performed with the cecal intubation rate of 97.8%.

RESULTS

The overall adenoma detection rate was 51.3% [95% confidence interval (CI), 50.5%-52.1%] of which 61.0% (95% CI, 59.9%-62.1%) was in men, and 39.1% (95% CI, 37.8%-40.3%) in women (P<0.01). The mean number of adenoma per positive colonoscopy was 1.94 (95% CI, 1.90-1.97). Adenoma, advanced adenoma, or cancer were found in 7732 (55.5%) colonoscopies. A total of 862 (6.2%) CRC cases were found. Only 161 (18.7%) carcinomas were situated in the right colon. A total of 597 (70.2%) patients with cancer were in the early clinical stages (N, negative; 194 22.8%) of all cancers were cured with only endoscopic resection.

CONCLUSIONS

In the NCSP, CRC was found in 6.2% of those participants attending colonoscopy, with 81.3% of carcinomas found in the left colon. A localized clinical stage was found in 70.2% participants. In 22.8% of CRC patients, cancer was cured with endoscopic resection only.

Association between bowel habits and quality of bowel preparation for colonoscopy

The effectiveness of colonoscopy is highly dependent on the quality of bowel preparation. Although many studies have previously evaluated the role of cleansing methods and dosing regimens, few have examined the association between bowel habits and subsequent bowel preparation. Here, we aimed to evaluate the impact of bowel habits on the quality of bowel preparation.A total of 404 patients who underwent a total colonoscopy and completed a personal bowel habit questionnaire at Korea University Hospital between December 2012 and December 2013 were enrolled. The usual stool form of patients was classified into 7 categories according to the Bristol Stool Scale (BSS). The quality of bowel preparation was determined during colonoscopy according to the Ottawa Bowel Preparation Scale (OBPS). Segment scores of ≥3 or total OBPS scores of >7 were defined as poor bowel preparation.Poor bowel preparation was reported in 9.4% of observed colonoscopies. The odds ratio (OR) of poor bowel preparation being associated with infrequent bowel movements (<3/week) was 5.00 (95% confidence interval [CI], 1.91-13.1, P = .001). BSS types 1 and 2 tended to have an association with poor bowel preparation, but the association was statistically insignificant (OR: 2.38; 95% CI, 0.90-6.33, P = .082). After adjusting for age, sex, drinking, presence of diabetes mellitus, and bowel preparation regimen, infrequent bowel movement (<3/week) was still significantly associated with poor bowel preparation. When subdividing by colonic segment, it was significantly associated with poor bowel preparation in all segments.Infrequent bowel movement (<3/week) was significantly associated with poor bowel preparation.

A Modified Bowel Preparation Regimen for Colonoscopy Providing the Patients' Satisfaction and Convenience

Background

A complete cleansing of the bowel is a critical factor that impacts the diagnostic accuracy of colonoscopies. However, the common bowel preparation regimen of two 45 mL doses of sodium phosphate (2×NaP) often leads to uncomfortable symptoms and subsequently lower patient adherence. To improve patient adherence and satisfaction, we proposed a modified regimen composed of two sennoside tablets and one bottle of NaP (S+NaP) and we then evaluated bowel preparation quality and patient satisfaction.

Material/Methods

A total of 531 patients who underwent colonoscopies at the outpatient coloproctology clinic from January 2016 to December 2016 were retrospectively reviewed. Eligible patients were divided into two groups: S+NaP group (n=93) and 2×NaP group (n=60). We compared bowel preparation quality, adenoma detection rate (ADR), self-reported patient satisfaction scores, and adverse events among the two groups.

Results

Regarding high bowel preparation quality, our results showed that there was no significant difference among the two groups (p=0.775), as well as no significant differences in ADRs (p=0.187). However, a lower proportion of nausea was found in the S+NaP group compared to the 2×NaP group (24.7% versus 41.7%, respectively, p=0.028). In addition, patients in the S+NaP group were more likely to be very satisfied with the regimen compared with patients in the 2×NaP group (odds ratio: 5.58; 95% confidence interval: 2.36–13.213, p<0.001).

Conclusions

Our modified bowel preparation regimen, S+NaP, yielded significantly higher patient satisfaction with less nausea while maintaining similar bowel preparation quality.

Impact of Resected Colon Site on Quality of Bowel Preparation in Patients Who Underwent Prior Colorectal Resection

BACKGROUND AND AIM

Various factors are known to be associated with quality of bowel preparation (QBP), but have rarely been investigated in patients with prior colorectal resection. The aim of this study was to investigate variables associated with bowel preparation in patients with prior colorectal resection.

MATERIALS AND METHODS

A total of 247 patients with prior colorectal resection and undergone surveillance colonoscopy were consecutively chosen. One clinician performed endoscopy for all patients. QBP was rated using Aronchick grade and was categorized as either satisfactory (Aronchick grades, 1 to 3) or unsatisfactory (Aronchick grades, 4 and 5). Factors associated with QBP were analyzed.

RESULTS

Unsatisfactory bowel preparation was detected in 49 patients (19.8%). There was no difference in QBP on the basis of sex, age, body mass index, hypertension history, diabetes mellitus history, smoking habits, time after surgery, resected colon length, or bowel preparation method. Operation method was marginally associated with QBP (P=0.056). When we dichotomized patients into right-side colon preservation or not, the right colon preservation group showed a significant association with poor QBP on univariate (22.3% vs. 7.5%, P=0.028) and multivariate analysis (odds ratio, 3.6; 95% confidence interval, 1.0-12.3; P=0.038).

CONCLUSION

Patients with a preserved right colon were associated with poor bowel preparations compared with patients who underwent right-side colon resection. When preparing patients with history of colorectal resection for colonoscopy, these differences should be considered for better bowel preparation.

Video capsule colonoscopy in routine clinical practice

BACKGROUND

Colon capsule endoscopy (CCE) offers direct mucosal visualisation without sedation or gas insufflation required in conventional colonoscopy (CC). However, evidence for the role of CCE as an adjunct or alternative to CC remains equivocal. In this observational cohort study, we report our experience of using CCE to investigate patients with suspected colon pathology at a tertiary referral centre.

METHODS

From 2007-2015, consecutive patients requiring colonoscopy were recruited from a tertiary care centre in Malmo, Sweden. Data collected: patient demographics, indication for CCE, findings, bowel cleansing, colon transit time (CTT) and completeness of colon examination.

RESULTS

Seventy-seven patients (57 F/20 F, median age 56 years) were included. The reason for CCE was previously incomplete or refused CC in 39 and 26 cases, and follow up of previous findings in 12 cases, respectively. The main clinical indications were gastrointestinal (GI) bleeding (n=28; 36%) and suspected inflammatory bowel disease (IBD) or follow-up of known IBD (n=23; 30%). CCE was complete in 58/77 (75%) patients. In 3 patients the colon was not reached; in the other 16, the capsule reached the rectum (n=4), sigmoid (n=6), descending colon (n=5) and transverse colon (n=1). Findings were: normal CCE (n=15; 19%) colonic diverticula (n=29; 38%), polyps (n=17; 22%), active IBD (n=12; 16%), haemorrhoids (n=8; 10%), colonic angioectasia (n=4; 5%) and cancer (n=1; 1%). Small-bowel findings were recorded in 8 (10%) patients. All patients tolerated bowel preparation and CCE well. Two patients with an ulcerated small-bowel stricture and cancer respectively experienced temporary capsule retention with spontaneous resolution.

CONCLUSIONS

CCE is a well-tolerated alternative to CC, but requires technological improvement and optimisation of clinical practice to meet current reference standards. Although further technical development is required, CCE may complement or even replace CC for certain clinical indications.

Subjective taste to polyethylene glycol is associated with efficacy of right colon preparation

AIM

A prospective observational trial with preparations using polyethylene glycol (PEG) to compare patient compliance and adverse events according to individual subjective taste.

METHODS

A total of 299 outpatients (mean ± standard deviation [SD] 56.5 ± 13.8 years, 172 males) were recruited for our study. We assessed the efficacy of bowel preparation, subjective taste to their regimens, compliance and adverse events during the preparation.

RESULTS

We achieved adequate preparation in 267 (89.3%). A total of 124 patients (41.5%) had 'unacceptable taste' to their regimens. The patients with acceptable taste had better compliance than the patients with unacceptable taste (p = .009). The patients with unacceptable taste had more frequent adverse events such as nausea, vomiting and abdominal bloating than the patients with acceptable taste (all p < .001, Table 2). Patients with unacceptable taste (16.1%) had more frequent inadequate preparation in overall colon than patients with acceptable taste (6.9%, p = .011). There was a significant difference in the efficacy of preparation of right colon between the two groups (p = .004).

CONCLUSION

Subjective taste to PEG is associated with efficacy of right colon preparation. In addition, subjective taste to PEG is associated with compliance and adverse events.

Administering Polyethylene Glycol Electrolyte Solution Via a Nasogastric Tube: Pulmonary Complications

BACKGROUND

Patients sometimes require insertion of a nasogastric tube for the administration of a large volume of a polyethylene glycol electrolyte solution. If the tube is malpositioned, the risk for direct instillation of the solution into the lung increases. The risk for aspiration also increases if the infusion rate exceeds gastrointestinal tolerance.

PURPOSE

To review published cases of patients' experiencing adverse pulmonary events after administration of polyethylene glycol electrolyte solution via a nasogastric tube and to offer suggestions to prevent these outcomes.

METHODS

A search of the literature from 1993 through 2014 was performed by using the PubMed, MEDLINE, Cumulative Index to Nursing and Allied Health Literature, and Scopus databases.

RESULTS

In the 12 case reports located, none of the patients had radiographs to verify tube location before infusion of polyethylene glycol electrolyte solution. After symptoms developed in 3 children (ages 8-11 years), radiographs showed their tubes incorrectly positioned in the bronchus, lung, or esophagus; ports of a fourth child's tube were in the oropharynx. The remaining 8 patients (ages 5-86 years) never had radiographs to determine tube placement. Pulmonary complications from the infusions of polyethylene glycol electrolyte solution contributed to the death of 5 of the patients.

CONCLUSION

Relatively simple maneuvers to reduce the likelihood of adverse pulmonary events following the administration of large volumes of polyethylene glycol electrolyte solution via a nasogastric tube are well worth the cost and effort to protect patients from potential serious injury.

Clinical Practice Guidelines for the Use of Video Capsule Endoscopy

BACKGROUND & AIMS

Video capsule endoscopy (CE) provides a noninvasive option to assess the small intestine, but its use with respect to endoscopic procedures and cross-sectional imaging varies widely. The aim of this consensus was to provide guidance on the appropriate use of CE in clinical practice.

METHODS

A systematic literature search identified studies on the use of CE in patients with Crohn's disease, celiac disease, gastrointestinal bleeding, and anemia. The quality of evidence and strength of recommendations were rated using the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach.

RESULTS

The consensus includes 21 statements focused on the use of small-bowel CE and colon capsule endoscopy. CE was recommended for patients with suspected, known, or relapsed Crohn's disease when ileocolonoscopy and imaging studies were negative if it was imperative to know whether active Crohn's disease was present in the small bowel. It was not recommended in patients with chronic abdominal pain or diarrhea, in whom there was no evidence of abnormal biomarkers typically associated with Crohn's disease. CE was recommended to assess patients with celiac disease who have unexplained symptoms despite appropriate treatment, but not to make the diagnosis. In patients with overt gastrointestinal bleeding, and negative findings on esophagogastroduodenoscopy and colonoscopy, CE should be performed as soon as possible. CE was recommended only in selected patients with unexplained, mild, chronic iron-deficiency anemia. CE was suggested for surveillance in patients with polyposis syndromes or other small-bowel cancers, who required small-bowel studies. Colon capsule endoscopy should not be substituted routinely for colonoscopy. Patients should be made aware of the potential risks of CE including a failed procedure, capsule retention, or a missed lesion. Finally, standardized criteria for training and reporting in CE should be defined.

CONCLUSIONS

CE generally should be considered a complementary test in patients with gastrointestinal bleeding, Crohn's disease, or celiac disease, who have had negative or inconclusive endoscopic or imaging studies.

Lack of benefit of active preparation compared with a clear fluid-only diet in small-bowel visualization for video capsule endoscopy: results of a randomized, blinded, controlled trial

BACKGROUND AND AIMS

Controversy remains regarding the type and amount of precapsule bowel cleansing required for small-bowel video capsule endoscopy (VCE). This study aims to assess the efficacy and tolerance of 2 active preparations and a control group of clear fluids only.

METHODS

Patients with clinical indications for VCE were randomized to (1) clear fluids only the evening before VCE, (2) 2 sachets of sodium picosulfate plus magnesium sulfate (P/MC) the evening before, or (3) 2 L of polyethylene glycol (PEG) the evening before. Diet instructions were the same for all 3 groups. Small-bowel cleansing was assessed in 3 ways: a 5-point ordinal scale (primary outcome), the percentage of time the small-bowel view was clear, and a validated computerized assessment of cleansing.

RESULTS

In total, 198 patients were randomized and 175 patients completed the trial with a mean age of 49.2 years. There was no clear benefit of active preparation with either P/MC or PEG over clear fluids only in the overall 5-point rating scale or in the distal fourth of each examination. There was no difference in diagnostic yield between groups. Significant differences were seen concerning tolerance of the preparations, with a higher proportion rating it as easy or very easy in the clear fluids-only group (93%) and the P/MC group (67%) than in the PEG group (13%) (P < .0001).

CONCLUSIONS

Small-bowel cleansing for VCE remains a controversial topic. This randomized control trial demonstrates no benefit in overall or distal small-bowel visualization with active preparation using either PEG or P/MC compared with clear fluids only. (Clinical trial registration number: NCT00677794.).

Randomized trial comparing oral sulfate solution with 4-L polyethylene glycol administered in a split dose as preparation for colonoscopy

BACKGROUND AND AIM

The present study aimed to evaluate the non-inferiority of low-volume oral sulfate solution (OSS) to 4-L polyethylene glycol (PEG) solutions administered in a split-dose regimen as bowel preparation for colonoscopy. The safety and tolerability were also compared between the two regimens.

METHODS

In this prospective, randomized, single-blind, active-control, parallel group, and non-inferiority trial, consecutive outpatients and health checkup recipients aged 19-65 years undergoing elective colonoscopy were enrolled to receive OSS or 4-L PEG in a split-dose regimen. The quality of bowel preparation was evaluated using the Boston Bowel Preparation Scale. The occurrence of any adverse events, acceptance, compliance, and satisfaction during bowel preparation were evaluated by participant interviews.

RESULTS

Overall, 210 participants were randomized, and 199 were administered by the study agents. Adequate bowel preparation was achieved in 98.0% (97/99) of the OSS group, which was non-inferior to the PEG group (96%; 96/100) with a difference of +2.8% (95% confidence interval; -2.8, +6.8). There were no differences in the incidence of adverse events except for abdominal pain, which was more frequent in the OSS (7.1%, 7/99) than in the PEG (1.0%, 1/100; P = 0.035) group. Acceptance, compliance, and satisfaction were significantly higher in the OSS than in the PEG group (all P < 0.05).

CONCLUSIONS

Split-dose OSS was non-inferior to split-dose 4-L PEG with regard to bowel preparation efficacy before colonoscopy in adult outpatients or screening colonoscopy recipients aged ≤65 years with acceptable safety and superior tolerability.

SAFETY OF MANNITOL USE IN BOWEL PREPARATION: a prospective assessment of intestinal methane (CH4) levels during colonoscopy after mannitol and sodium phosphate (NaP) bowel cleansing

BACKGROUND

- Adequate bowel preparation is critical for the quality of colonoscopy. Despite reported occurrence of colonic explosion due to methane and hydrogen production by bacterial fermentation during colonoscopy, gas exchange during the procedure is believed to be effective in lowering existing methane concentration, allowing for safe utilization of mannitol for bowel preparation. Thus, mannitol is widely used for bowel cleansing prior to colonoscopy, considering its low cost and effectiveness for bowel preparation.

OBJECTIVE

- The aim of this study was to assess the safety of mannitol for bowel preparation, when compared to sodium phosphate (NaP).

METHODS

- We conducted a prospective observational study in which 250 patients undergoing colonoscopy at Universidade Federal de São Paulo and Hospital Albert Einstein (São Paulo, Brazil) were approached for inclusion in the study. Patients received either mannitol (n=50) or NaP (n=200) for bowel preparation, based on physician indication. Study was conducted from August 2009 to December 2009. The main outcome of interest was presence of detectable levels of methane (CH4) during colonoscopy and reduction in such levels after gas exchange during the procedure. Methane concentrations were measured in three intestinal segments during scope introduction and withdrawal. Safety was assessed as the absence of high levels of methane, defined as 5%. Measurements were made using a multi-gas monitor (X-am 7000, Dräger Safety AG & Co. KGaA, Lübeck, Germany) connected to a plastic catheter introduced into the working channel of the colonoscope. Additional outcomes of interest included levels of O2. Methane and O2 levels are reported as ppm. Mean, difference and standard deviation of levels of gas measured in both moments were calculated and compared in both groups. Proportions of patients with detectable or high levels of methane in both groups were compared. Continuous variables were analyzed using t test and categorical variables using qui-square tests. The Ethics Committee in both study sites approved the study protocol.

RESULTS

- Patients in both groups were similar regarding demographics, colonoscopy indication, ASA status and quality of bowel preparation. Seven (3.5%) patients in the NaP group had methane detected during introduction of the endoscope. Methane levels became undetectable during withdrawal of the scope. None of the patients in the mannitol group had detectable levels of methane. O2 levels did not differ in the groups.

CONCLUSION

- This is the largest study to assess the safety of mannitol for bowel preparation, considering methane measurements. Our results indicate that mannitol use is as safe as NaP, and gas exchange was efficient in reducing methane concentrations.

Systematic review and meta-analysis: Sodium picosulphate with magnesium citrate as bowel preparation for colonoscopy

Background

An effective and tolerable bowel preparation is important to secure quality of colonoscopies. It remains unclear if sodium picosulphate with magnesium citrate (SPMC), which is considered a tolerable bowel preparation agent, is also an effective alternative for polyethylene glycol (PEG) and sodium phosphate (NaP).

Aim

The aim of this article is to compare effectiveness of SPMC to PEG and NaP through assessment of quality of bowel cleansing measured by validated tools.

Methods

We searched electronic databases up to January 2015. Only randomised controlled trials (RCTs) were included. Two authors independently performed selection of studies, risk of bias assessment and data extraction.

Results

Thirteen RCTs were included, with overall good quality, but large heterogeneity. SPMC had slightly better quality of bowel cleansing than PEG (pooled RR 1.06; 95% CI 1.02 to 1.11). In most trials SPMC was significantly better tolerated than PEG. There were no significant differences in effectiveness or tolerability between SPMC and NaP. Side effects were similar between agents, except for dizziness (pooled RR 1.71; 95% CI 1.32 to 2.21 in favour of PEG vs. SPMC) and vomiting (pooled RR 0.35; 95% CI 0.13 to 0.95 in favour of single-dose SPMC vs. split-dose).

Conclusions

SPMC is equally effective to NaP and little superior to PEG in terms of bowel cleansing. SPMC preparations were better tolerated than PEG preparations. SPMC may be considered as standard bowel preparation for colonoscopy.