Bowel preparation for colonoscopy: entering an era of increased expectations for efficacy

2L polyethylene glycol combined with castor oil versus 4L polyethylene glycol for bowel preparation before colonoscopy among inpatients

Inpatients are more likely to have inadequate bowel preparation compared to outpatients. Although experts recommend 4L split polyethylene glycol (PEG) preparation, bowel preparation with castor oil (CaO) was recently found to reduce the volume of solution required. The aim of the study was to evaluate the cleansing effect and safety of 2L-PEG with Cao in bowel preparation among inpatients. Our study retrospectively analyzed the medical records and colonoscopy reports of inpatients (n = 1251) who underwent colonoscopy in the Affiliated Changzhou No.2 People Hospital of Nanjing Medical University, and the inpatients were divided into 2L-PEG-CaO and 4L-PEG group according to different bowel preparation protocols. Boston Bowel Preparation Scale (BBPS) is used to assess bowel preparation efficacy before colonoscopy. Furthermore, we also calculated other outcomes, such as polyp or adenoma detection rates and adverse events. A total of 1251 patients undergoing colonoscopy were included in this study, 738 were taken 4L-PEG and 513 2L-PEG-CaO. Both inpatients groups were matched for baseline characteristics. The 2L-PEG-CaO group was significantly higher than the 4L-PEG group on both BBPS (7.26 ± 1.75 vs 7.06 ± 1.58, P = .043) and adequate bowel cleansing rates (83.2% vs 77.4%, P = .011). Regarding adverse events, the 4L-PEG group was significantly higher than the 2L-PEG-CaO group on the incidence of abdominal fullness (6.4% vs 9.6%, P = .045) and adverse events (33.7% vs 28.5%, P = .048). The 2L split PEG with CaO preparation increased quality of bowel cleansing and improved tolerance in inpatients. Bowel preparation with 2L-PEG-CaO is suitable alternative to traditional 4L split PEG bowel preparation for colonoscopy of inpatients.

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.

A Phase 2 Randomized Trial of DCL-101, a Novel Pill-Based Colonoscopy Prep, vs 4L Polyethylene Glycol-Electrolyte Solution

INTRODUCTION:

DCL-101, a novel Pill Prep, is compositionally identical to standard 4L polyethylene glycol-electrolyte solution (PEG-ELS) and delivers the salt encapsulated, with PEG 3350 coadministered as a taste-free oral solution. The aim of this study was to compare the safety, taste, and tolerability of DCL-101 with 4L PEG-ELS in outpatients preparing for colonoscopy, with a secondary objective to assess efficacy.

METHODS:

This was a multicenter, randomized, investigator-blinded, phase 2 clinical trial of 45 adult patients undergoing outpatient colonoscopy. Patients were randomized 2:1 to either DCL-101 (3L in cohort 1; 4L in cohort 2) or 4L PEG-ELS, each administered with split dosing. Safety was assessed over 3 post-treatment clinic visits. Tolerability was measured using the Lawrance Bowel-Preparation Tolerability Questionnaire and the Mayo Clinic Bowel Prep Tolerability Questionnaire. Efficacy was determined by expert central readers, blinded to treatment, using the Ottawa Bowel Preparation Quality Scale, Boston Bowel Preparation Scale, and Aronchick scale.

RESULTS:

Both DCL-101 doses had superior taste and tolerability relative to 4L PEG-ELS. All adverse events were grade 1 with no significant differences in adverse events among the 3 regimens. There were no significant differences in efficacy among the 3 treatments as defined by the centrally read Ottawa Bowel Preparation Quality Scale, Boston Bowel Preparation Scale, or Aronchick scores. There were no inadequate preps as judged by the site endoscopist.

DISCUSSION:

DCL-101 Pill Prep is a novel strategy that vastly improves the taste and tolerability of PEG-ELS solutions with safety and efficacy comparable with split-dose 4L PEG-ELS solutions.

Risk Factors for Suboptimal Bowel Preparation for Colonoscopy in Pediatric Patients

BACKGROUND/AIMS

Suboptimal bowel cleansing is common in children and can impact diagnostic and therapeutic outcomes. We aimed to identify risk factors for suboptimal bowel preparation for colonoscopy in pediatric patients.

METHODS

This was a retrospective study of all patients ages 0 to 21 years who underwent colonoscopy at a children's hospital from 2015 to 2019 in the United States. Demographics and clinical information were obtained from the electronic health record. The primary outcome was suboptimal bowel preparation measured by the endoscopist on a dichotomized Aronchik Scale. Univariate and multivariate regression modeling were used to determine independent predictors of suboptimal preparation.

RESULTS

Nine hundred and eight patients (mean age 12.17 years [±5.14], boys 465 (51.2%), were included in the analysis. Suboptimal preparation was noted in 242 (26.7%). On univariate analysis, suboptimal preparation was more common in those of younger age (38.6%), Medicaid (32.1%), Spanish as primary language (35.7%), and failure to thrive (FTT) (45.9%). Suboptimal preparations were less common in patients with inflammatory bowel disease (IBD) (11.6%). After adjustment for other covariates, IBD and FTT maintained their statistical associations, IBD (odds ratio [OR] 0.27 95% confidence interval [CI] 0.095-0.75, P =  0.01), FTT (OR 1.98 95% CI 1.28-3.06, P =  <0.01).

CONCLUSIONS

To our knowledge, this is the first investigation of pediatric patients to identify independent risk factors for suboptimal bowel preparation. We confirm Medicaid status and English as a second language as risk factors as well as highlight distinct associations from those reported in the adult literature including FTT and younger age. IBD was associated with optimal cleansing. Future research to understand the mechanisms of inferred risk or potential protection is required.

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.

1L- vs. 4L-Polyethylene glycol for bowel preparation before colonoscopy among inpatients: A propensity score-matching analysis

BACKGROUND

Inpatients are at risk for inadequate colon cleansing. Experts recommend 4L-polyethylene-glycol (PEG) solution. A higher colon cleansing adequacy rate for a hyperosmolar 1L-PEG plus ascorbate prep has been recently reported.

AIMS

We aimed to determine whether 1L-PEG outperforms 4L-PEG among inpatients.

METHODS

post-hoc analysis of a large Italian multicenter prospective observational study among inpatients (QIPS study). We performed a propensity score matching between 1L-PEG and 4L-PEG group. The primary outcome was the rate of adequate colon cleansing as assessed by unblinded endoscopists through Boston scale. Secondary outcome was the safety profile.

RESULTS

Among 1,004 patients undergoing colonoscopy, 724 (72%) were prescribed 4L-PEG and 280 (28%) 1L-PEG. The overall adequate colon cleansing rate was 69.2% (n = 695). We matched 274 pairs of patients with similar distribution of confounders. The rate of patients with adequate colon cleansing was higher in 1L-PEG than in 4L-PEG group (84.3% vs. 77.4%, p = 0.039). No different shift in serum concentration of electrolytes (namely Na⁺, K⁺, Ca²⁺), creatinine and hematocrit were observed for both preparations.

CONCLUSION

We found a higher rate of adequate colon cleansing for colonoscopy with the 1L-PEG bowel prep vs. 4L-PEG, with apparent similar safety profile, among inpatients. A confirmatory randomized trial is needed. (ClinicalTrials.gov no: NCT04310332).

Evaluation of bowel preparation quality in patients with a history of colorectal resection

BACKGROUND/AIMS

Suboptimal bowel function can negatively affect colon cleansing for colonoscopy after surgery. Very few studies have compared the relationship between the colorectal resection and the bowel preparation quality. We postulated that the colon cleansing quality in patients with a history of colorectal surgery might not be inferior to that of patients with no resection history.

MATERIALS AND METHODS

Overall, 200 patients were enrolled in the study and distributed into two groups: the resection group (RG) and the control group. The surgical maneuvers were classified as right colectomy, left colectomy, and rectosigmoidectomy. The bowel preparation was performed using 2-L low-volume or 4-L high-volume regimens, and the preparation quality was evaluated using the modified Boston Bowel Preparation Scale (BBPS).

RESULTS

There were no significant differences in achieving adequate cleansing observed between the RG and the control group (modified BBPS of 6-9; 88% vs. 88%). According to the logistic regression analysis of the RG, patients with a left colon resection had an odds ratio (OR) of 0.27 (p=0.003) for achieving a successful cleansing, and the low-volume preparation (OR=3.092, p=0.023) was the main predictor of a successful cleansing procedure. However, a longer time between colonoscopy and surgery was not related to unsuccessful bowel cleansing.

CONCLUSION

Our study demonstrates that a history of colorectal surgery is not a risk factor for inadequate colon cleansing.

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

INTRODUCTION

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.

Bowel Preparations Administered the Morning of Colonoscopy Provide Similar Efficacy to a Split Dose Regimen: A Meta Analysis

BACKGROUND

Comparative efficacy of same-day bowel preparations for colonoscopy remains unclear.

AIMS

A meta-analysis of randomized controlled trials comparing the efficacy of same-day versus split dose bowel preparations for colonoscopy.

METHODS

A systematic search was conducted in MEDLINE, clinicaltrials.gov, Cochrane Registry, EMBASE, SCOPUS, Web of Science and CINAHL. Studies were gathered using keywords: "morning preparation", "morning bowel preparation", "same day bowel preparation", and "colonoscopy." Pooled estimates of bowel preparation quality were analyzed among studies with categorical and continuous outcomes according to relative risk (RR) or mean difference (MD). A random effects model was chosen a priori for all analyses.

RESULTS

A total of 1216 studies were retrieved with 15 trials meeting inclusion criteria. The categorical outcome of high quality bowel preparation for any same-day bowel preparation versus any split preparation was no different with a RR 0.95 [0.90;1.00] (P=0.62). Adenoma detection rate (ADR) was not different between groups, RR 0.97 [0.79;1.20] (P=0.81). Willingness to repeat and tolerability did not differ (RR 1.14 [0.96,1.36] (P=0.14) and RR 1.00 [0.96;1.04] (P=0.98), respectively. Adverse events were similar except for bloating, which was less frequent among the same-day preparation group, RR 0.68 [0.40;0.94] (P=0.02).

CONCLUSION

No clinically significant differences were noted among recipients of same day or split dose regimens. Adenoma detection rate, willingness to repeat and tolerability were similar, but bloating and interference with sleep favored the same-day preparations. Given lack of clinical differences, patient preference should dictate timing of colonoscopy preparation.

Split- versus single-dose preparation tolerability in a multiethnic population: decreased side effects but greater social barriers

BACKGROUND

This study was performed to compare patient-reported tolerability and its barriers in single- vs. split-dose 4-L polyethylene glycol (PEG) bowel preparation for colonoscopy in a large multiethnic, safety-net patient population.

METHODS

A cross-sectional, dual-center study using a multi-language survey was used to collect patient-reported demographic, medical, socioeconomic, and tolerability data from patients undergoing outpatient colonoscopy. Univariate and multivariate analyses were used to identify demographic and clinical factors significantly associated with patient-reported bowel preparation tolerability.

RESULTS

A total of 1023 complete surveys were included, of which 342 (33.4%) completed single-dose and 681 (66.6%) split-dose bowel preparation. Thirty-nine percent of the patients were Hispanic, 50% had Medicaid or no insurance, and 34% had limited English proficiency. Patients who underwent split-dose preparation were significantly more likely to report a tolerable preparation, with less severe symptoms, than were patients who underwent single-dose preparation. Multiple logistic regression revealed that male sex and instructions in the preferred language were associated with tolerability of the single-dose preparation, while male sex and concerns about medications were associated with tolerability of the split-dose preparation.

CONCLUSIONS

In a large multiethnic safety-net population, split-dose bowel preparation was significantly more tolerable and associated with less severe gastrointestinal symptoms than single-dose preparation. The tolerability of split-dose bowel preparation was associated with social barriers, including concerns about interfering with other medications.

Endoscopy for patients affected by inflammatory bowel disease: bowel preparation and sedation

Endoscopy has a key role in the management of inflammatory bowel disease (IBD). It is helpful in the diagnosis, in case of relapse, refractoriness, before therapeutic changes, after surgery as well as in the assessment of mucosal healing and in the surveillance of colo-rectal cancer. IBD patients are intended to undergo several times the examination during their lifespan. Bowel preparation and sedation highly contribute to high-quality colonoscopy. Areas covered: Few studies addressed preparation and sedation in the field of IBD. In this review, we focused our attention on the available evidences about bowel preparation and sedation in patients with IBD. Expert commentary: In recent years, the goal of medical treatment in IBD is shifting from clinical improvement in symptoms towards mucosal healing. High-quality endoscopy will gain even more importance in the management of IBD. It is important to locate the most effective preparation and the best sedation in patient with IBD to perform a high-quality endoscopy.

Cystic Fibrosis Colorectal Cancer Screening Consensus Recommendations

BACKGROUND & AIMS

Improved therapy has substantially increased survival of persons with cystic fibrosis (CF). But the risk of colorectal cancer (CRC) in adults with CF is 5-10 times greater compared to the general population, and 25-30 times greater in CF patients after an organ transplantation. To address this risk, the CF Foundation convened a multi-stakeholder task force to develop CRC screening recommendations.

METHODS

The 18-member task force consisted of experts including pulmonologists, gastroenterologists, a social worker, nurse coordinator, surgeon, epidemiologist, statistician, CF adult, and a parent. The committee comprised 3 workgroups: Cancer Risk, Transplant, and Procedure and Preparation. A guidelines specialist at the CF Foundation conducted an evidence synthesis February-March 2016 based on PubMed literature searches. Task force members conducted additional independent searches. A total of 1159 articles were retrieved. After initial screening, the committee read 198 articles in full and analyzed 123 articles to develop recommendation statements. An independent decision analysis evaluating the benefits of screening relative to harms and resources required was conducted by the Department of Public Health at Erasmus Medical Center, Netherlands using the Microsimulation Screening Analysis model from the Cancer Innervation and Surveillance Modeling Network. The task force included recommendation statements in the final guideline only if they reached an 80% acceptance threshold.

RESULTS

The task force makes 10 CRC screening recommendations that emphasize shared, individualized decision-making and familiarity with CF-specific gastrointestinal challenges. We recommend colonoscopy as the preferred screening method, initiation of screening at age 40 years, 5-year re-screening and 3-year surveillance intervals (unless shorter interval is indicated by individual findings), and a CF-specific intensive bowel preparation. Organ transplant recipients with CF should initiate CRC screening at age 30 years within 2 years of the transplantation because of the additional risk for colon cancer associated with immunosuppression.

CONCLUSIONS

These recommendations aim to help CF adults, families, primary care physicians, gastroenterologists, and CF and transplantation centers address the issue of CRC screening. They differ from guidelines developed for the general population with respect to the recommended age of screening initiation, screening method, preparation, and the interval for repeat screening and surveillance.

Efficacy of Prucalopride in bowel cleansing before colonoscopy: Results of a pilot study

Colonoscopy is a crucial diagnostic instrument for colorectal cancer screening and an adequate bowel preparation is definitely decisive for the success of the procedure. Especially in elderly patients, bowel cleansing is considered a big issue, because it is often poorly tolerated for many reasons (like inability to swallow large volume of liquids or unlikable taste); this can cause a suboptimal preparation that may lead to miss a neoplastic lesion. There is relatively little data about how to improve preparation tolerability. The purpose of our pilot study was to analyze the effect of prucalopride (Resolor^®), a highly selective serotonin 5HT4 receptor agonist used for chronic constipation for its ability to stimulate gastrointestinal peristalsis, undertaken the day before colonoscopy, followed by half volume of polyethylene glycol solution. We found that this can be a good and safe method to achieve an adequate and better-tolerated colon cleansing.

The management of 'hard-to-prepare' colonoscopy patients

Effective bowel cleansing is crucial for high quality colonoscopy. A notable portion of patients still present with low quality bowel preparation prior to their colonoscopy, compromising the overall quality of their colonoscopy. Areas covered: This review focuses on the main strategies that can improve the cleansing quality with a special interest on those clinical conditions that have been associated with a poor bowel preparation quality, such as patients with chronic constipation, history of bowel resection, liver cirrhosis, diabetes mellitus and chronic kidney disease. The review provides a practical and evidence-based approach to help clinicians in the management of 'hard-to-prepare' patients. Expert commentary: In the past few years, the quality of colonoscopy has become a hot topic and bowel cleansing is a crucial part of it; however, the approach to patients with an increased risk of poor bowel preparation quality is still not always supported by high-quality evidence, since most of these patients are routinely excluded from the clinical studies. Trials focused on this subgroup of patients are recommended to provide tailored bowel preparation regimens and guarantee high-quality procedures.

Scheduling rules for patients with diabetes mellitus that facilitate split-dosing improve the quality of bowel preparation for colonoscopy

Background & aims

An adequate bowel preparation for colonoscopy is best achieved by giving the cleansing regimen as a split-dose with the second dose given 4–6 hours before the procedure. This can be difficult to administer to diabetics who are preferentially scheduled for early morning procedures. We examined the impact on bowel preparation quality of scheduling diabetics for mid-morning (9:30 am or later) procedures rather than early morning procedures (7:30–9:00 AM) to facilitate a split-dose preparation.

Methods

Historical cohort study of 34,415 patients (1,805 diabetics) age 18–74 years without significant comorbidities who underwent an outpatient colorectal cancer screening-related colonoscopy either before (2013) or after (2014) a unit wide change in scheduling practices for diabetics. The primary outcome was the rate of inadequate bowel preparation. Secondary outcomes include the rate of procedures complete to the cecum, procedure duration and detection rates of polyps, any colorectal cancer screening-relevant lesion (adenoma, sessile serrated adenoma, large proximal hyperplastic polyp) and advanced adenomas.

Results

From 2013 to 2014, the proportion of diabetics with an inadequate bowel preparation decreased from 7.7% to 3.2% (95% confidence interval for the difference 2.2%–6.8%, P<0.00005). There was no significant change in the proportion of non-diabetics with inadequate preparation (2% in both years). There was no change in secondary outcomes in diabetics from 2013 to 2014.

Conclusions

Preferentially scheduling diabetic patients later in the morning that more conveniently allowed for a split dose bowel preparation resulted in decreased rates of inadequate bowel preparation without disadvantaging other patients.

Efficacy and safety of PICOPREP tailored dosing compared with PICOPREP day-before dosing for colon cleansing: a multi-centric randomised study

Background and study aims The success of any colonoscopy procedure depends upon the quality of bowel preparation. We evaluated the efficacy and safety of a new tailored dosing (TD) regimen compared with the approved PICOPREP day-before dosing regimen (DBD) in the European Union. Patient and methods Patients (≥ 18 years) undergoing colonoscopy were randomised (2:1) to TD (Dose 1, 10 - 18 hours; Dose 2, 4 - 6 hours before colonoscopy) or DBD (Dose 1 before 8:00AM on the day before colonoscopy; Dose 2, 6 - 8 hours after Dose 1). The primary endpoint of overall colon cleansing efficacy was based on total Ottawa Scale (OS) scores (0 - 14, excellent-worst). The key secondary endpoint was a binary endpoint based on the ascending colon OS (success 0 or 1, failure [≥ 2]). Convenience and satisfaction were evaluated similar to the primary and key secondary endpoints. Safety and tolerability were also evaluated. Results Use of the PICOPREP TD regimen resulted in a statistically significant reduction in the mean total Ottawa Scale score compared to the PICOPREP DBD regimen (-3.93, 95 % confidence intervals [CI]: - 4.99, - 2.97; P < 0.0001) in the intent-to-treat analysis set. The PICOPREP TD regimen also resulted in a statistically significant increase in the odds of achieving an ascending colon OS score ≤ 1, compared to the PICOPREP DBD regimen (estimated odds ratio 9.18, 95 % CI: 4.36, 19.32; P < 0.0001). There was no statistically significant difference in the overall rate of treatment-emergent adverse events (12 % (TD) and 5.7 % (DBD), respectively, P = 0.2988). The convenience and satisfaction were comparable in the two groups. Conclusion The TD regimen was superior to the DBD regimen for overall and ascending colon cleansing efficacy. ClinicalTrials.gov Identifier: NCT02239692.

Randomized controlled trial: Standard versus supplemental bowel preparation in patients with Bristol stool form 1 and 2

Background

Bristol stool form 1 and 2 is an important predictor of inadequate bowel preparation.

Aim

To evaluate the efficacy of supplemental preparation in bowel cleansing quality among patients with Bristol stool form 1 and 2, as well as the feasibility of tailored bowel preparation guided by Bristol stool form scale.

Methods

Patients with Bristol stool form 1 and 2 from 3 Chinese tertiary hospitals randomly received either 2 L PEG-ELP (group A) or 10 mg bisacodyl plus 2 L PEG-ELP (group B); patients with Bristol stool form 3 to 7 received 2 L PEG-ELP (group C) for bowel preparation. The primary endpoint is the rate of adequate bowel reparation for the whole colon. The adequate bowel preparation rate for separate colon segments, the polyp detection rate (PDR), tolerability, acceptability, sleeping quality and compliance were evaluated as secondary endpoints.

Results

700 patients were randomized. In per-protocol analysis, patients in group B attained significantly higher successful preparation rate than group A (88.7% vs. 61.2%, p<0.001) and similar with group C (88.7% vs. 85.0%, p = 0.316). The PDR in group B was significantly higher than group A (43.2% vs. 25.7%, p<0.001). Acceptability was much higher in group B and C.

Conclusions

10 mg bisacodyl plus 2 L PEG-ELP can significantly improve both bowel preparation quality and PDR in patients with Bristol stool form 1 and 2. Bristol stool form scale may be an easy and efficient guide for tailored bowel preparation before colonoscopy.

A Customized Mobile Application in Colonoscopy Preparation: A Randomized Controlled Trial

OBJECTIVES

Adherence with diet and prescribed purgative is essential for proper cleansing with low-volume bowel preparations. The aim of this work was to assess the effect of a customized mobile application (App) on adherence and quality of bowel preparation.

METHODS

One hundred and sixty (160) eligible patients scheduled for elective colonoscopy were randomly assigned to paper (control) or App-based instructions. The preparation consisted of low-fiber diet for 2 days, clear fluids for one day and split-dose sodium picosulfate/magnesium citrate (SPS). Before colonoscopy, information was collected regarding adherence with, and utility of the provided instructions. The colonoscopists, blinded to assignment, graded bowel preparation using the Aronchick, Ottawa, and Chicago preparation scales. The primary endpoint was adherence with instructions. Quality of preparation was a secondary endpoint.

RESULTS

No difference in overall adherence or bowel cleanliness was observed between the study arms. Adherence was reported in 82.4% of App vs. 73.4% of controls (P=0.40). An adequate bowel preparation on the Aronchick scale was noted in 77.2 vs. 82.5%, respectively (P=0.68). Mean scores on the Ottawa and Chicago scales were also similar. Gender, age, time of colonoscopy, and BMI did not influence preparation or adherence. Compliance with the clear fluid diet component was noted in 94% of patients with BMI<30 vs. 77% with BMI≥30 (P<0.01). SPS was well tolerated by 81.9% of patients. The App was user-friendly and received higher overall rating in this respect than paper instructions (P<0.01).

CONCLUSIONS

SPS is well tolerated and effective for bowel cleansing regardless of instruction method. Customized smartphone applications are effective, well-accepted and could replace standard paper instructions for bowel preparation.ClinicalTrials.gov: NCT02410720.

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.).

Cost Effectiveness of Screening Colonoscopy Depends on Adequate Bowel Preparation Rates - A Modeling Study

Background

Inadequate bowel preparation during screening colonoscopy necessitates repeating colonoscopy. Studies suggest inadequate bowel preparation rates of 20–60%. This increases the cost of colonoscopy for our society.

Aim

The aim of this study is to determine the impact of inadequate bowel preparation rate on the cost effectiveness of colonoscopy compared to other screening strategies for colorectal cancer (CRC).

Methods

A microsimulation model of CRC screening strategies for the general population at average risk for CRC. The strategies include fecal immunochemistry test (FIT) every year, colonoscopy every ten years, sigmoidoscopy every five years, or stool DNA test every 3 years. The screening could be performed at private practice offices, outpatient hospitals, and ambulatory surgical centers.

Results

At the current assumed inadequate bowel preparation rate of 25%, the cost of colonoscopy as a screening strategy is above society’s willingness to pay (<$50,000/QALY). Threshold analysis demonstrated that an inadequate bowel preparation rate of 13% or less is necessary before colonoscopy is considered more cost effective than FIT. At inadequate bowel preparation rates of 25%, colonoscopy is still more cost effective compared to sigmoidoscopy and stool DNA test. Sensitivity analysis of all inputs adjusted by ±10% showed incremental cost effectiveness ratio values were influenced most by the specificity, adherence, and sensitivity of FIT and colonoscopy.

Conclusions

Screening colonoscopy is not a cost effective strategy when compared with fecal immunochemical test, as long as the inadequate bowel preparation rate is greater than 13%.

Sensory characterization of bowel cleansing solutions

AIM: To evaluate the sensory characteristics of commercial bowel cleansing preparations.

METHODS: Samples of 4 commercially available bowel cleansing preparations, namely polyethylene glycol electrolyte solution (PEG), PEG + ascorbic acid (PEG-Asc), sodium picosulfate (SPS), and oral sodium sulfate (OSS) were prepared according to the manufacturer’s instructions. Descriptive analysis was conducted (n = 14) using a 15-cm line scale with the Compusense at-hand^® sensory evaluation software. Acceptability testing (n = 80) was conducted using the 9-point hedonic scale. In addition, a Just-About-Right (JAR) scale was included for the four basic tastes to determine their intensity compatibility with acceptability levels in the products.

RESULTS: Samples were significantly different, in descriptive analysis, for all attributes (P < 0.05) except for sweetness. SPS received the highest ratings for turbidity, viscosity appearance, orange odor and orange flavor; PEG-Asc for citrus odor and citrus flavor; OSS for sweetener taste, sweet aftertaste, bitterness, astringency, mouthcoating, bitter aftertaste and throatburn, and along with PEG-Asc, the highest ratings for saltiness, sourness and adhesiveness. Acceptability results showed significant differences between the various samples (P < 0.05). SPS received significantly higher ratings for overall acceptability, acceptability of taste, odor and mouthfeel (P < 0.05). JAR ratings showed that PEG and PEG-Asc were perceived as slightly too salty; SPS and OSS were slightly too sweet, while SPS, PEG-Asc and OSS were slightly too sour and OSS slightly too bitter. While using small sample volumes was necessary to avoid unwanted purgative effects, acceptability ratings do not reflect the true effect of large volumes intake thus limiting the generalization of the results.

CONCLUSION: Further improvements are needed to enhance the sensory profile and to optimize the acceptability for better compliance with these bowel cleansing solutions.

Safety of a 1-Day Polyethylene Glycol 3350 Bowel Preparation for Colonoscopy in Children

OBJECTIVES

Electrolyte-free polyethylene glycol powder (PEG-3350) has been widely used for colonoscopy preparation (prep); however, limited safety data on electrolyte changes exists with 1-day prep regimens. The primary aim of this study was to determine the proportion of patients with significant serum chemistry abnormalities before and at the time of colonoscopy. Secondary aims included evaluation of prep tolerance and bowel cleansing efficacy.

METHODS

We performed a prospective descriptive observational study of pediatric patients scheduled for outpatient colonoscopy who received our standard 1-day, weight-based 4 g/kg PEG-3350 prep with a single stimulant laxative dose and had serum chemistry testing within 60 days before and at the time of colonoscopy. A standardized bowel cleanliness tool (Aronchick scale) was completed by the endoscopist.

RESULTS

One hundred fifty-five patients had serum electrolytes data pre- and postprep. Comparison of each patient's chemistries demonstrated statistical equivalence with the 1 exception of blood urea nitrogen levels (P = 0.56). Hypokalemia was detected postprep in 37 subjects (24%), but none had a serum level <3.3 mmol/L, which was deemed to be of no clinical significance. Five patients were hypoglycemic post prep; 3 were 7 years or younger (P = 0.02). The colon cleanliness rating was excellent or good in 77% and suboptimal in 23% of patients.

CONCLUSIONS

A 1-day, weight-based PEG-3350 bowel prep in children appears safe. Changes in electrolyte levels and renal function were not clinically significant. Children of 7 years or younger seem to be at a higher risk of hypoglycemia compared with older children.

More Is Not Always Better: A Randomized Trial Of Low Volume Oral Laxative, Enemas, And Combination Of Both Demonstrate That Enemas Alone Are Most Efficacious For Preparation For Flexible Sigmoidoscopy

OBJECTIVES

Colon cleansing for flexible sigmoidoscopy using a standard fleet enema does not provide adequate cleansing in a significant number of patients. We tested whether the addition of a low-volume oral cleansing agent could mitigate this challenge without significantly compromising patient tolerance.

HYPOTHESIS

Oral picosulfate with magnesium citrate (P/MC) would enhance the colon cleansing of patients undergoing sigmoidoscopy, as assessed by the modified Ottawa Bowel Preparation Score.

METHODS

A randomized single blinded trial comparing (1) a single dose (i.e., one sachet) of oral sodium picosulfate plus magnesium citrate (P/MC) administered the night before, (2) a single dose oral P/MC the night before plus sodium phosphate enema 1 h before leaving home, and (3) sodium phosphate enema alone 1 h before leaving home for flexible sigmoidoscopy was conducted on outpatients referred for sigmoidoscopy for symptom assessment.

RESULTS

A total 120 patients were randomized to the study groups. The main indication for sigmoidoscopy was investigation of rectal bleeding (n=80). There was no significant difference in bowel cleansing quality, measured by the endoscopist blinded to preparation, between P/MC, P/MC plus enema, and enema alone as measured by the modified Ottawa Bowel Preparation Scale (P=0.34) or the Aronchick Scale (P=0.13). Both oral P/MC regimens were associated with higher incidence of nausea, abdominal pain, bloating, and interrupted sleep than enema alone (P<0.05).

CONCLUSIONS

A single dose of oral P/MC administered the night before did not result in better colon cleansing for sigmoidoscopy when used alone or with an enema and was associated with more side effects (NCT 01554111).

Split-dose menthol-enhanced PEG vs PEG-ascorbic acid for colonoscopy preparation

AIM

To compare the efficacy and palatability of 4 L polyethylene glycol electrolyte (PEG) plus sugar-free menthol candy (PEG + M) vs reduced-volume 2 L ascorbic acid-supplemented PEG (AscPEG).

METHODS

In a randomized controlled trial setting, ambulatory patients scheduled for elective colonoscopy were prospectively enrolled. Patients were randomized to receive either PEG + M or AscPEG, both split-dosed with minimal dietary restriction. Palatability was assessed on a linear scale of 1 to 5 (1 = disgusting; 5 = tasty). Quality of preparation was scored by assignment-blinded endoscopists using the modified Aronchick and Ottawa scales. The main outcomes were the palatability and efficacy of the preparation. Secondary outcomes included patient willingness to retake the same preparation again in the future and completion of the prescribed preparation.

RESULTS

Overall, 200 patients were enrolled (100 patients per arm). PEG + M was more palatable than AscPEG (76% vs 62%, P = 0.03). Completing the preparation was not different between study groups (91% PEG + M vs 86% AscPEG, P = 0.38) but more patients were willing to retake PEG + M (54% vs 40% respectively, P = 0.047). There was no significant difference between PEG + M vs AscPEG in adequate cleansing on both the modified Aronchick (82% vs 77%, P = 0.31) and the Ottawa scale (85% vs 74%, P = 0.054). However, PEG + M was superior in the left colon on the Ottawa subsegmental score (score 0-2: 94% for PEG + M vs 81% for AscPEG, P = 0.005) and received significantly more excellent ratings than AscPEG on the modified Aronchick scale (61% vs 43%, P = 0.009). Both preparations performed less well in afternoon vs morning examinations (inadequate: 29% vs 15.2%, P = 0.02).

CONCLUSION

4 L PEG plus menthol has better palatability and acceptability than 2 L ascorbic acid- PEG and is associated with a higher rate of excellent preparations; Clinicaltrial.gov identifier: NCT01788709.

Polyethylene glycol plus an oral sulfate solution as a bowel cleansing regimen for colon capsule endoscopy: a prospective, single-arm study in healthy volunteers

OBJECTIVES

As with colonoscopy, adequate bowel cleansing is essential prior to colon capsule endoscopy (CCE). Because CCE requires that the capsule traverse the entire gastrointestinal tract during the examination, laxative 'boosters' are used. The objective of this prospective, single-center, single-arm study was to evaluate the safety of a bowel preparation consisting of polyethylene glycol (PEG) plus an oral sulfate solution.

METHODS

Subjects were healthy volunteers aged 50-75 years old with normal baseline serum chemistry. The bowel preparation consisted of 4 Senna tablets, 4 liters of PEG (split dose), 10 mg metoclopramide, 2 oral sulfate solution boosters (6 oz. and 3 oz.), and 10 mg bisacodyl. Serum chemistry was performed at baseline, following PEG intake, 24 hours after bisacodyl administration, and at 7 days post procedure (in subjects with abnormal 24 hour results). The primary endpoints were the percentage of subjects with a clinically significant change in serum chemistry at the last test and the adverse event (AE) rate.

RESULTS

A total of 25 subjects were enrolled. The serum chemistry was normal in all subjects at the final evaluation. One subject showed a slight elevation in creatinine (1.08 mg/dl 7 days post procedure from 0.84 mg/dl at baseline), deemed not clinically significant. Another subject had a transient elevation in serum creatinine (from 1.01 mg/dl at baseline to 1.45 mg/dl at 24 hours after the bowel preparation); values returned to near baseline at 7 days post procedure (1.06 mg/dl). There were no serious AEs, three moderate AEs related to the bowel preparation (nausea, headache, elevated creatinine) and two mild unrelated AEs (chills, abdominal cramping).

CONCLUSIONS

A bowel cleansing regimen of PEG plus an oral sulfate solution can be used in healthy volunteers. These data provide support for the continued study of this regimen in future CCE clinical trials and in medical practice.

What Influences the Quality of Prevention Colonoscopy?

Background

Colorectal cancer still has a high incidence and mortality. Although colonoscopy is considered as gold standard of colorectal cancer screening, there still exists an unsatisfactory level of adenomas missed in screening and surveillance colonoscopy. Furthermore, patients bear the burden of potentially unpleasant and painful examination and preparation procedures.

Method

A search of the literature using PubMed was carried out, supplemented by a review of the programs of the Digestive Disease Week (DDW) and the United European Gastroenterology Week (UEGW) 2011-2013.

Results

Several new approaches to colonoscopy were described: water, CO₂ and cap colonoscopy, and application of spasmolytics such as hyoscine butylbromide and glucagon. The use of these methods does not necessitate the purchase of new endoscopes. They are feasible and safe, facilitate achieving the aim of more comfort and less pain, and perhaps allow lower doses of sedatives to be used. However, a clear effect on procedure time is lacking. Furthermore, the published data do not consistently answer the question of whether these techniques have a positive impact on the most important goal, the better detection of carcinoma precursors.

Conclusion

More efforts to optimize bowel preparation have to be made to improve visualization of the mucosal surface. The most reliable criteria for the quality of screening and surveillance colonoscopy remain a minimum cecal intubation rate of >90%, a withdrawal time of at least 6 or better 9 min, and an adenoma detection rate of >20%. These results should be achieved with a complication rate lower than 1%, including polypectomy.

Advances in bowel preparation for colonoscopy

Precolonoscopy bowel preparation is adequate to identify lesions larger than 5 mm about 70% to 75% of the time, but the opportunity for further improvement exists. The use of high-quality formulations with established efficacy rates of 90% or greater, identification of patients who are at increased risk of an inadequate preparation, as well as patient education and motivation to be invested in the process further improves the success of cleansing. Endoscopists should strive to achieve an adequate bowel preparation in 85% or more of patients. High-quality colonoscopy requires high-quality bowel cleansing.

Optimizing bowel cleansing for colonoscopy

Adequate bowel cleansing is essential for complete examination of the colon mucosa during colonoscopy. Suboptimal bowel preparation has potential adverse consequences, such as missed pathologic abnormalities, the need for repeated procedures, and increased procedure-related complications. Several factors can predict individuals at increased risk for inadequate bowel preparation. If predictors of inadequate bowel preparation are identified, then education should be intensified and a more aggressive bowel regimen recommended. On completion of this article, you should be able to (1) define the frequency of inadequate colon preparations, (2) identify predictors of poor bowel preparation, and (3) use a more aggressive bowel regimen when clinically indicated.

Intraprocedural cleansing work during colonoscopy and achievable rates of adequate preparation in an open-access endoscopy unit

BACKGROUND

Rates of adequate bowel preparation in the 60% to 80% range continue to be reported for colonoscopy.

OBJECTIVE

To describe the rate of adequate bowel preparation and intraprocedural work needed to achieve this rate in an open-access endoscopy unit. Universal split dosing and regimens tailored to medical predictors of inadequate preparation were used.

DESIGN

Prospective observational study.

SETTING

Academic hospital outpatient endoscopy unit and ambulatory surgery center.

PATIENTS

Outpatients undergoing colonoscopy.

INTERVENTIONS

Prospective assessment of preparation quality for colonoscopy during insertion and after intraprocedural cleansing in 525 patients.

MAIN OUTCOME MEASUREMENTS

Rates of adequate preparation and work required to improve cleansing quality. Work time for cleaning was measured with a stopwatch.

RESULTS

Adequate preparation to allow recommendation of standard screening or surveillance intervals was achieved in 96% of patients, including 6% for whom preparation was adequate only after intraprocedural cleansing work. The mean time for intraprocedural cleaning was 4.1 minutes and constituted 17% of total procedure time. Work time for cleaning and fluid volume injected increased when worse preparation grades were identified before cleaning.

LIMITATIONS

Single-center study with low percentage (4%) of patients receiving Medicaid.

CONCLUSION

An open-access unit using split-dose bowel cleansing preparations can achieve high rates of adequate bowel preparation for colonoscopy. Intraprocedural cleansing accounts for a substantial fraction of the total procedure time in colonoscopy and is an important contributor to high rates of adequate preparation.

Split-dose menthol-enhanced PEG vs PEG-ascorbic acid for colonoscopy preparation

AIM: To compare the efficacy and palatability of 4 L polyethylene glycol electrolyte (PEG) plus sugar-free menthol candy (PEG + M) vs reduced-volume 2 L ascorbic acid-supplemented PEG (AscPEG).

METHODS: In a randomized controlled trial setting, ambulatory patients scheduled for elective colonoscopy were prospectively enrolled. Patients were randomized to receive either PEG + M or AscPEG, both split-dosed with minimal dietary restriction. Palatability was assessed on a linear scale of 1 to 5 (1 = disgusting; 5 = tasty). Quality of preparation was scored by assignment-blinded endoscopists using the modified Aronchick and Ottawa scales. The main outcomes were the palatability and efficacy of the preparation. Secondary outcomes included patient willingness to retake the same preparation again in the future and completion of the prescribed preparation.

RESULTS: Overall, 200 patients were enrolled (100 patients per arm). PEG + M was more palatable than AscPEG (76% vs 62%, P = 0.03). Completing the preparation was not different between study groups (91% PEG + M vs 86% AscPEG, P = 0.38) but more patients were willing to retake PEG + M (54% vs 40% respectively, P = 0.047). There was no significant difference between PEG + M vs AscPEG in adequate cleansing on both the modified Aronchick (82% vs 77%, P = 0.31) and the Ottawa scale (85% vs 74%, P = 0.054). However, PEG + M was superior in the left colon on the Ottawa subsegmental score (score 0-2: 94% for PEG + M vs 81% for AscPEG, P = 0.005) and received significantly more excellent ratings than AscPEG on the modified Aronchick scale (61% vs 43%, P = 0.009). Both preparations performed less well in afternoon vs morning examinations (inadequate: 29% vs 15.2%, P = 0.02).

CONCLUSION: 4 L PEG plus menthol has better palatability and acceptability than 2 L ascorbic acid- PEG and is associated with a higher rate of excellent preparations; Clinicaltrial.gov identifier: NCT01788709.

Optimal bowel preparation--a practical guide for clinicians

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