The impact of colon preparation timing on colonoscopic detection of colorectal neoplasms--a prospective endoscopist-blinded randomized trial

Colonoscopy screening and surveillance guidelines

The Colonoscopy Screening and Surveillance Guidelines were developed by the Japan Gastroenterological Endoscopy Society as basic guidelines based on the scientific methods. The importance of endoscopic screening and surveillance for both detection and post-treatment follow-up of colorectal cancer has been recognized as essential to reduce disease mortality. There is limited high-level evidence in this field; therefore, we had to focus on the consensus of experts. These clinical practice guidelines consist of 20 clinical questions and eight background knowledge topics that have been determined as the current guiding principles.

Educational Video on the WeChat Platform Can Effectively Improve the Quality of Bowel Preparation: A Prospective, Randomized, Controlled Study

Bowel preparation is a core issue in the quality of colonoscopy. We attempted to investigate whether an educational video via WeChat (a widely used mobile social media app) improved the compliance of patients and quality of bowel preparation. We enrolled 198 colonoscopy patients aged 35-70 years. They were randomly divided into the WeChat group (100 cases) and the control group (98 cases). The outcomes were the compliance of patients in the bowel preparation process and quality of the bowel preparation according to the Boston Bowel Preparation Scale. Participants' compliance increased markedly in the WeChat group compared with the control group (P < 0.01). The total Boston Bowel Preparation Scale score was significantly higher in the WeChat group than in the control group (7.02 ± 1.75 vs. 6.45 ± 1.91, respectively, p < .05). The intubation time (minutes) of colonoscopy in the WeChat group was shorter than that in the control group (7.38 ± 1.37 vs. 7.88 ± 1.39, respectively, p < .05). Our data confirmed that an educational video via WeChat can improve the quality of bowel preparation. It can also increase the compliance of bowel preparation and shorten the intubation time of colonoscopy.

Strategies to Improve Inadequate Bowel Preparation for Colonoscopy

Bowel cleansing is one of the most important parameters included in the evaluation of colonoscopy quality. The available evidence suggests that inadequate bowel preparation reduces the diagnostic yield of colorectal neoplasia and increases post-colonoscopy colorectal cancer risk. Nowadays, up to 30% of patients referred for colonoscopy have a poor bowel cleansing. Recently, several studies have analyzed the risk factors for inadequate bowel cleansing as well as the strategies to optimize bowel preparation. In this review, we have focused on summarizing the available evidence in this field.

Strategies to optimise the quality of bowel cleansing

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

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

BACKGROUND AND AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Prospective analysis of factors associated with inadequate bowel preparation for colonoscopy in actual clinical practice

Background/Aims

Inadequate bowel preparation can result in prolonged procedure time and increased missed lesion and complication rates. This prospective study aimed to evaluate bowel preparation quality and identify the predictive factors for inadequate bowel preparation in actual clinical practice.

Methods

We included 399 patients who underwent colonoscopy between June 2015 and July 2016. Using the Aronchick bowel preparation scale, we defined a score ≤2 as adequate preparation and a score >2 as inadequate preparation.

Results

Mean patient age was 58.38±12.97 years; 60.6% were male. Indications for colonoscopy included screening (69.7%) and surveillance after polyp removal (21.3%). A split-dose regimen was prescribed to 55.4% of patients. The inadequate bowel preparation rate was 28.1%. Overall, the median time between the last bowel preparation agent dose and start of colonoscopy was 5.0 hours (range, 1.5-16.0 hours); that of the adequate group was 5.0 hours (range, 1.5-16.0 hours); and that of the inadequate group was 5 hours (range, 2-23 hours). The mean bowel preparation scale score of the ascending colon (1.94±0.25) was significantly higher than that of other colon segments. On multivariate analysis, elderly age, history of cerebrovascular disease, history of gastrectomy or appendectomy, and total preparation solution uptake <2 L were the independent predictors of inadequate bowel preparation.

Conclusions

The inadequate bowel preparation rate was 28.1%. Risk factors included elderly age and history of cerebrovascular disease or abdominal surgery. Patients with these risk factors require special care and education.

Same-Day Single Dose of 2 Liter Polyethylene Glycol is Not Inferior to The Standard Bowel Preparation Regimen in Low-Risk Patients: A Randomized, Controlled Trial

OBJECTIVES

Split dose of 4 l polyethylene glycol (PEG) is currently the standard regimen for bowel preparation (BP). However, it may be unnecessary for patients without high risks (e.g., old age, constipation, and diabetes, and so on) for inadequate BP. The study aimed to compare the efficacy of bowel cleansing between low-risk patients receiving same-day, single dose of low-volume (SSL) PEG vs. standard regimen.

METHODS

This prospective, randomized, observer-blinded, non-inferiority study enrolled low-risk patients in three centers. Patients undergoing colonoscopy were randomized (1:1) to the SSL or standard group. The primary outcome was adequate BP, defined by Boston Bowel Preparation Score (BBPS) ≥6 and each segmental score ≥2. Secondary outcomes included adverse events, cecal intubation rate, and patient willingness to repeat BP, and so on.

RESULTS

Among 2,532 patients eligible for the study, 940 (37.1%) were at low risk and 792 (31.3%) at high risk for inadequate BP. The low-risk patients were randomly allocated to the SSL (n=470) or standard group (n=470). The baseline characteristics of the two groups were similar. Intention-to-treat analysis showed that adequate BP was achieved in 88.1% in the SSL group and 87.0% in the standard group (relative risk (RR) 1.10, 95% confidence interval (CI): 0.75-1.63, P=0.621). The overall BBPS was 7.3±1.2 and 7.3±1.3, respectively (P=0.948). No significant differences were found between the two groups with regards to the right, transverse, and left-segmental colon BBPS (all P>0.05). However, in terms of adverse events, patients in the SSL group reported less nausea (19.6% vs. 29.9%), vomiting (5.3% vs. 11.4%), and abdominal discomfort (2.2% vs. 6.0%) compared with those in the standard group. More patients in the SSL group were willing to repeat BP (94.0% vs. 89.5%, P=0.015).

CONCLUSIONS

For low-risk patients, the SSL regimen was not inferior to the split dose of 4 l PEG for adequacy of BP. Single dose of low-volume regimen had significantly fewer adverse events. This simplified regimen may be preferable in the "easy-to prepare" population.

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.

Effect of Functional Status on the Quality of Bowel Preparation in Elderly Patients Undergoing Screening and Surveillance Colonoscopy

Background/Aims

Optimal bowel preparation is essential for successful screening or for surveillance colonoscopy (SC). Inadequate bowel preparation is associated with older age, the male gender, and the presence of certain comorbidities. However, the association between patients’ functional status and bowel preparation quality has not been studied. We prospectively examined the relationship between functional status, namely, the ability to perform activities of daily living (ADLs) and ambulate, and the quality of bowel preparation in elderly patients undergoing SC.

Methods

Before undergoing SC, 88 elderly patients were surveyed regarding their functional status, specifically regarding their ability to perform ADLs and ambulate a quarter of a mile. Gastroenterologists then determined the quality of the bowel preparation, which was classified as either adequate or inadequate. Then, the frequency of inadequate bowel preparation in patients who did or did not experience difficulty performing ADLs and ambulating was calculated.

Results

Difficulty ambulating (unadjusted odds ratio [OR], 4.83; p<0.001), difficulty performing ADLs (OR, 2.93; p=0.001), and history of diabetes (OR, 2.88; p=0.007) were significant univariate predictors of inadequate bowel preparation. After adjusting for the above variables, only difficulty ambulating (adjusted OR, 5.78; p=0.004) was an independent predictor of inadequate bowel preparation.

Conclusions

Difficulty with ambulation is a strong predictor of inadequate bowel preparation in elderly patients undergoing SC.

Systematic Review: Outcomes by Duration of NPO Status prior to Colonoscopy

Background/Aims

Variation exists among anesthesia providers as to acceptable timing of NPO (“nothing by mouth”) for elective colonoscopy procedures. There is a need to balance optimal colonic preparation, patient convenience, and scheduling efficiency with anesthesia safety concerns. We reviewed the evidence for the relationship between NPO timing and aspiration incidence and colonoscopy rescheduling.

Methods

We searched MEDLINE (1990–April 2015) for English language studies of any design and included them if at least one bowel preparation regimen was completed within 8 hours of colonoscopy. Study characteristics, patient characteristics, and outcomes were abstracted and verified by investigators. We determined risk of bias for each study and overall strength of evidence for primary and secondary outcomes.

Results

We included 28 randomized controlled trials (RCTs), 2 controlled clinical trials, and 10 observational reports. Six studies reported on aspiration; none found that shorter NPO status prior to colonoscopy increased aspiration risk, though studies were not designed to assess this outcome (low strength of evidence). One RCT found fewer rescheduled procedures following split-dose preparation but NPO status was not well-documented (insufficient evidence).

Conclusions

Aspiration incidence requiring hospitalization during colonoscopy with moderate or deep sedation is very low. No study found that shorter NPO status prior to colonoscopy increased aspiration risk. We did not find direct evidence of the effect of NPO status on colonoscopy rescheduling.

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%.

Controlled Dietary Restriction With a Prepackaged Low-Residue Diet Before Colonoscopy Offers Better-Quality Bowel Cleansing and Allows the Use of a Smaller Volume of Purgatives: A Randomized Multicenter Trial

BACKGROUND

Bowel preparation is burdensome, and less-demanding preparation procedures are needed. Few studies have investigated the effects of low-residue diet and prepackaged low-residue diet in combination with low-volume polyethylene glycol-electrolyte lavage solution during colonoscopy preparation.

OBJECTIVE

We compared self-prepared low-residue diets with prepackaged low-residue diets in combination with low-volume polyethylene glycol.

DESIGN

This was a single-blinded, 3-arm, multicenter, randomized controlled trial.

SETTING

Colonoscopies were conducted in outpatient settings at 3 centers in Taiwan.

PATIENTS

The study included 180 patients (age range, 20-75 years) who were scheduled for colonoscopy.

INTERVENTIONS

Three groups were compared: group A included self-prepared, 1-day, low-residue diets with a same-day 2.0-L single-dose of polyethylene glycol; group B included prepackaged low-residue diets plus 2.0 L of polyethylene glycol; and group C included prepackaged low-residue diets plus 1.5 L of polyethylene glycol.

MAIN OUTCOME MEASURES

The outcome measures were adherence, bowel-cleansing level, and patient satisfaction.

RESULTS

One third of the subjects in group A, but none in the prepackaged low-residue diets groups, violated the dietary restrictions. The proportion of right-segment preparation failure was 15.0%, 1.7%, and 6.7% (p = 0.025). Accordingly, treatment B was superior to A (p = 0.008). Among subjects violating the low-residue diets guideline, the right-segment preparation failure rate was 25%. According to a multivariate analysis, low-residue diet compliance (adjusted OR = 6.55 (95% CI, 1.83-23.43)) and BMI were predictors of right-sided preparation adequacy, but the volume of polyethylene glycol ingested was not a predictor. Compared with group A, a greater proportion of subjects in groups B and C reported satisfaction.

LIMITATIONS

Patients with high BMI and severe constipation were excluded from this study. This study included only an Asian population.

CONCLUSIONS

The prepackaged low-residue diet provides excellent adherence, better bowel cleansing, and a better experience than a self-prepared low-residue diet. With good dietary compliance, 1.5 L of polyethylene glycol provides effective preparation.

Constipation, fiber intake and non-compliance contribute to inadequate colonoscopy bowel preparation: a prospective cohort study

OBJECTIVE

Adequate bowel preparation is important for colonoscopy. Currently available evidence on the determinants of poor bowel preparation is largely derived from studies in Western countries. We aimed to identify the risk factors for inadequate bowel preparation for colonoscopy in the Chinese population.

METHODS

In this single-center study, patients admitted to the Outpatient Department between March 2013 and December 2015 and had indications for colonoscopy were prospectively enrolled. Questionnaires were administered to the patients. Their characteristics and procedure-related parameters such as procedure time were recorded. Bowel preparation was assessed using Boston bowel preparation scale score.

RESULTS

A total of 409 patients with a mean age of 48.8 ± 12.9 years were enrolled in the study, 60.9% of whom were men. On univariate analysis, poor educational level (P = 0.020), chronic constipation (P = 0.001), taking no physical exercise after medication (P < 0.001), a high-fiber diet during the 24-h period immediately preceding the colonoscopy (P < 0.001), incomplete intake of medication (P < 0.001), the passage of yellow or dark stools before colonoscopy (P < 0.001), waiting time (P = 0.001) and stool frequency after medication (P = 0.048) were significantly associated with inadequate bowel preparation. On multivariate analysis, chronic constipation [odds ratio (OR) 2.05, 95% confidence interval (CI) 1.31-3.23, P = 0.002], incomplete intake of the medication (OR 2.77, 95% CI 1.47-5.21, P = 0.002) and a high-fiber diet within 24 h before colonoscopy (OR 2.15, 95% CI 1.40-3.28, P < 0.001) were independent risk factors for inadequate bowel preparation.

CONCLUSIONS

Chronic constipation, poor compliance with treatment and high-fiber diet were predictors of poor bowel preparation. Patients with these risk factors require more effective strategies for bowel preparation.

Chromoscopy versus conventional endoscopy for the detection of polyps in the colon and rectum

BACKGROUND

Although conventional colonoscopy is the most accurate test available for the investigation of the colorectum for polyps, data exist that raise concerns about its sensitivity. Chromoscopy (spraying dye onto the surface of the colon to make polyps more visible) may be one way of enhancing the ability of colonoscopy to detect polyps, particularly diminutive flat lesions, which otherwise may be difficult to detect.

OBJECTIVES

To determine whether the use of chromoscopy enhances the detection of polyps and neoplasia during endoscopic examination of the colon and rectum.

SEARCH METHODS

We searched the following databases: Cochrane Colorectal Cancer Group Specialised Register (October 2015), Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library; Issue 10, 2015), MEDLINE (January 1950 to October 2015), EMBASE (January 1974 to October 2015), and ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (both November 2015). We also handsearched abstracts from relevant meetings from 1980 to 2015. Search terms included 'randomised trials' containing combinations of the following: 'chromoscopy' 'colonoscopy' 'dye-spray' 'chromo-endoscopy' 'indigo-carmine' 'magnifying endoscopy'.

SELECTION CRITERIA

We included all prospective randomised trials comparing chromoscopic with conventional endoscopic examination of the whole of the colon and rectum. We excluded studies of people with inflammatory bowel disease or polyposis syndromes and any studies that combined chromoscopy with additional interventions (cap assistance, water-perfused, etc.).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the methodological quality of potentially eligible trials, and two review authors independently extracted data from the included trials. Outcome measures included the detection of polyps (neoplastic and non-neoplastic), the detection of diminutive lesions, the number of participants with multiple neoplastic lesions, and the extubation time.

MAIN RESULTS

We included seven trials (2727 participants) in this update. Five trials were of sufficiently similar design to allow for pooled results. Two trials differed substantially in design and were included in a subgroup analysis. All the trials had some methodological drawbacks. However, combining the results showed a significant difference in favour of chromoscopy for all detection outcomes. In particular, chromoscopy was likely to yield significantly more people with at least one neoplastic lesion (odds ratio (OR) 1.53, 95% confidence interval (CI) 1.31 to 1.79; 7 trials; 2727 participants), and at least one diminutive neoplastic lesion (OR 1.51, 95% CI 1.19 to 1.92; 4 trials; 1757 participants). Significantly more people with three or more neoplastic lesions were also detected, but only when studies that used high-definition colonoscopy in the control group were excluded (OR 4.63, 95% CI 1.99 to 10.80; 2 trials; 519 participants). None of the included studies reported any adverse events related to the use of the contrast dye.

AUTHORS' CONCLUSIONS

There is strong evidence that chromoscopy enhances the detection of neoplasia in the colon and rectum. People with neoplastic polyps, particularly those with multiple polyps, are at increased risk of developing colorectal cancer. Such lesions, which presumably would be missed with conventional colonoscopy, could contribute to the interval cancer numbers on any surveillance programme.

Gastric residual volume after split-dose compared with evening-before polyethylene glycol bowel preparation

BACKGROUND AND AIMS

Split-dose bowel preparation for colonoscopy results in superior preparation quality. However, some endoscopy units remain hesitant to prescribe split-dose preparation given theoretical concerns about possible aspiration caused by gastric residual fluid when a second dose is given close to the time of endoscopy. Our aim was to compare gastric residual volume (GRV) in patients taking split-dose bowel preparation and those taking preparation the evening before colonoscopy.

METHODS

We performed a prospective observational comparison of GRV among random inpatients undergoing same-day EGD and colonoscopy either after a split-dose bowel preparation or after a bowel preparation the prior evening.

RESULTS

GRV was measured in 150 patients undergoing EGD and colonoscopy: 75 who completed a split-dose bowel preparation 2 to 3 hours before endoscopy and 75 who completed the bowel preparation regimen the prior evening. The mean GRV 2 to 3 hours after the last ingestion of bowel preparation among split-dose group patients was 21 ± 24 mL (± standard deviation; range, 0 to 125 mL), which was not different from the mean GRV of 24 ± 22 mL (range, 0 to 135 mL) in patients who ingested the preparation the prior evening (P = .08). GRV had no association with the presence of diabetes, gastroparesis, or opioid use.

CONCLUSIONS

GRV is the same after a split preparation and fasting for 2 to 3 hours or after preparation with overnight fasting. The data suggest that the risk of aspiration is identical after either preparation technique and thus that sedation for colonoscopy can be performed safely 2 hours after bowel preparation ingestion.

The Colonoscopist's Expertise Affects the Characteristics of Detected Polyps

Background/Aims:

The influence of the endoscopist on the polyp detection rate (PDR) is underappreciated in clinical practice. Moreover, flat lesions or lesions of the proximal colon are more difficult to detect. Here, we evaluated the differences in the PDR and the characteristics of detected polyps according to the experience of the colonoscopist.

Methods:

We collected data on 2,549 patients who underwent screening colonoscopy performed by three fellows. The PDR was calculated according to the percentage of patients who had at least one polyp (method A) and according to the percentage of detected lesions (method B). The primary outcome included the change in the PDR, and the secondary outcome included the change in the characteristics of the detected polyps with increasing experience of the colonoscopist.

Results:

No proportional correlation was found between the PDR and increasing experience in colonoscopy with method A; however, with method B, the PDR increased after 400 colonoscopies (p=0.0209). With method B, the detection rates of small polyps (<5 mm) (p=0.0015) and polyps in proximal sites (p=0.0050) increased after 300 colonoscopies.

Conclusions:

Our study demonstrated that the quality of a colonoscopy, measured by using the PDR, may increase when performed by experienced fellows.

A randomized trial to compare the efficacy and tolerability of sodium picosulfate-magnesium citrate solution vs. 4 L polyethylene glycol solution as a bowel preparation for colonoscopy

PURPOSE

The purpose of this study is to compare the efficacy and acceptability of an evening-before regimens of sodium picosulfate/magnesium citrate (SPMC) and polyethylene glycol (PEG) as bowel cleansers and to explore the results of a same-day regimen of SPMC.

METHODS

Multicenter, randomized, observer-blinded, parallel study carried out in subjects who were 18-80 years old and were undergoing diagnostic colonoscopy for the first time. The primary outcome was treatment success, which was a composite outcome defined by (1) the evaluation of the overall preparation quality as "excellent" or "good" by two blinded independent evaluators with the Fleet(®) Grading Scale for Bowel Cleansing and (2) a subject's acceptability rating of "easy to take" or "tolerable." The primary outcome was analyzed using a logistic regression with site, gender, and age group (age ≥65 years and <65 years) as factors.

RESULTS

Four hundred ninety subjects were included in the efficacy evaluation. Although treatment success was significantly higher in subjects assigned to the evening-before regimen of SPMC vs. subjects assigned to the evening-before PEG, when evaluating the two individual components for treatment success, there were significant differences in the ease of completion but not in the quality of preparation. The same-day SPMC regimen was superior to both the evening-before regimen of SPMC and PEG in terms of the quality of preparation, especially regarding the proximal colon.

CONCLUSIONS

An evening-before regimen of SPMC is superior to an evening-before regimen of PEG in terms of subject's acceptability. The same-day SPMC regimen provides better cleansing levels in the proximal colon.

Colonoscopy performance is stable during the course of an extended three-session working day

BACKGROUND

Three-session days were introduced in our endoscopy unit to accommodate the increased demand resulting from the introduction of the National Health Service Bowel Cancer Screening Programme (BCSP). Cecal intubation rate (CIR) and adenoma detection rate (ADR) may decline with time during a standard working day, but data are lacking for an extended three-session day. We assessed colonoscopy performance in an extended three-session day.

METHODS

Colonoscopies performed during the year 2011 were retrospectively analyzed. The CIR and ADR were analyzed according to the time of day when procedures were done: morning (AM), afternoon (PM), or evening (EVE). Because of an expected higher incidence of adenomas in the BCSP patients, ADR was analyzed according to indication (BCSP or non-BCSP).

RESULTS

Of the 2574 colonoscopies, 1328 (51.7 %) were in male patients and 1239 (48.3 %) in female patients with a median age of 63 years (interquartile range [IQR], 51 - 70). Of the 2574 colonoscopies, 1091 (42.4 %) were performed in AM lists, 994 (38.6 %) in PM lists, and 489 (19 %) in EVE lists. Time of day did not affect the CIRs for the AM, PM, and EVE lists (90.5 %, 90.1 %, and 89.9 %, respectively; χ (2) [2, N = 2540] = 0.15, P = 0.927). The CIR was reduced in female patients and those with poor bowel preparation (P < 0.05). After exclusion of the BCSP patients, the ADR was lower in the EVE lists than in the AM and PM lists on univariate analysis, but on multivariate analysis, this difference was not significant (P > 0.05). The ADR was significantly higher in patients older than 60 years and in men (P < 0.001). Queue position did not independently influence the CIR or ADR.

CONCLUSIONS

Colonoscopy quality does not appear to depend on time of day or queue position in an extended three-session day.

Contrasting Perspectives of Anesthesiologists and Gastroenterologists on the Optimal Time Interval between Bowel Preparation and Endoscopic Sedation

Background. The optimal time interval between the last ingestion of bowel prep and sedation for colonoscopy remains controversial, despite guidelines that sedation can be administered 2 hours after consumption of clear liquids. Objective. To determine current practice patterns among anesthesiologists and gastroenterologists regarding the optimal time interval for sedation after last ingestion of bowel prep and to understand the rationale underlying their beliefs. Design. Questionnaire survey of anesthesiologists and gastroenterologists in the USA. The questions were focused on the preferred time interval of endoscopy after a polyethylene glycol based preparation in routine cases and select conditions. Results. Responses were received from 109 anesthesiologists and 112 gastroenterologists. 96% of anesthesiologists recommended waiting longer than 2 hours until sedation, in contrast to only 26% of gastroenterologists. The main reason for waiting >2 hours was that PEG was not considered a clear liquid. Most anesthesiologists, but not gastroenterologists, waited longer in patients with history of diabetes or reflux. Conclusions. Anesthesiologists and gastroenterologists do not agree on the optimal interval for sedation after last drink of bowel prep. Most anesthesiologists prefer to wait longer than the recommended 2 hours for clear liquids. The data suggest a need for clearer guidelines on this issue.

Impact of the quality of bowel cleansing on the efficacy of colonic cancer screening: a prospective, randomized, blinded study

OBJECTIVES

Efficacy of two low volume bowel cleansing preparations, polyethylene glycol plus ascorbate (PEG + Asc) and sodium picosulfate/magnesium citrate (NaPic/MgCit), were compared for polyp and adenoma detection rate (PDR and ADR) and overall cleansing ability. Primary endpoint was PDR (the number of patients with ≥ 1 polypoid or flat lesion recorded by the colonoscopist).

METHODS

Diagnostic, surveillance or screening colonoscopy patients were enrolled into this investigator-blinded, multi-center Phase IV study and randomized 1:1 to receive PEG + Asc (administered the evening before and the morning of colonoscopy, per label) or NaPic/MgCit (administered in the morning and afternoon the day before colonoscopy, per label). The blinded colonoscopist documented any lesion and assessed cleansing quality (Harefield Cleansing Scale).

RESULTS

Of 394 patients who completed the study, 393 (PEG + Asc, N = 200; NaPic/MgCit, N = 193) had a colonoscopy. Overall PDR for PEG+Asc versus NaPic/MgCit was 51.5% versus 44.0%, p = 0.139. PDR and ADR on the right side of the bowel were significantly higher with PEG + Asc versus NaPic/MgCit (PDR: 56[28.0%] versus 32[16.6%], p = 0.007; ADR: 42[21.0%] versus 23[11.9%], p = 0.015), as was detection of flat lesions (43[21.5%] versus 25[13.0%], p = 0.025). Cleansing quality was better with PEG + Asc than NaPic/MgCit (98.5% versus 57.5% considered successful cleansing). Overall, there were 132 treatment-emergent adverse events (93 versus 39 for PEG+Asc and NaPic/MgCit, respectively). These were mainly mild abdominal symptoms, all of which were reported for higher proportions of patients in the PEG+Asc than NaPic/MgCit group. Twice as many patients in the NaPic/MgCit versus the PEG + Asc group reported tolerance of cleansing solution as 'very good'.

CONCLUSIONS

Compared with NaPic/MgCit, PEG + Asc may be more efficacious for overall cleansing ability, and subsequent detection of right-sided and flat lesions. This is likely attributable to the different administration schedules of the two bowel cleansing preparations, which may positively impact the detection and prevention of colorectal cancer, thereby improving mortality rates.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01689792.

Difficult colonoscopy score identifies the difficult patients undergoing unsedated colonoscopy

Background

Many factors have been found to affect the difficulty of colonoscope insertion, such as age, gender, body mass index (BMI), history of abdominal surgery and operator etc. However, a scoring system may be more useful to predict the difficulty during colonoscopy.

Methods

The individual and procedure-related data of 616 patients undergoing colonoscopy were prospectively collected from December 2013 through February 2014 in Xijing Hospital of Digestive Diseases. Cox regression analysis was used to identify high-risk factors associated with difficulty of colonoscopy. A predicting model with the difficult colonoscopy score (DCS) was developed.

Results

Total cecum intubation rate was 98.9% (609/616). Advanced age, lower BMI, inexperienced operator and fair or poor sleep quality were identified as independent factors of prolonged insertion time (all p < 0.05), which were used to develop the DCS. Based on the score, patients could be divided into high-risk and low-risk groups with distinct incomplete rates within 10 min (42.0% vs. 16.5%, p < 0.001). Compared with those with DCS ≤ 1, patients with DCS > 1 had increased insertion time (10.6 ± 0.7 min vs. 6.9 ± 0.2 min, p < 0.001) and pain score (1.9 ± 1.5 vs. 1.4 ± 1.4, p = 0.002). More abdominal compression (36.9% vs. 16.8%, p < 0.001) and position change (51.4% vs. 22.6%, p < 0.001) were needed in this group of patients.

Conclusion

Patients with DCS > 1 had longer insertion time, higher pain score and needed more abdominal compression and position changes. DCS was useful for predicting the difficulty of colonoscope intubation.

(ClinicalTrials.gov NCT02105025 05/05/2014).

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-015-0273-7) contains supplementary material, which is available to authorized users.

Development of a risk score to stratify symptomatic adults referred for colonoscopy

BACKGROUND AND AIM

With an increasing burden on overstretched colonoscopy services, a simple risk score for significant pathology in symptomatic patients may aid in the prioritization of patients.

METHODS

A derivative study of a risk score model for colonic neoplasia (colorectal carcinoma [CRC] and advanced adenoma) and CRC alone was conducted in symptomatic adults referred for an index colonoscopy. The accuracy of the final model was assessed by the area under the curve (AUC) of the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit statistic.

RESULTS

A total of 1013 subjects (mean age 59.9 ± 13.7 years, 52.3% females) from a multi-ethnic Asian background (Chinese 56%, Malay 20.4%, Indian 21.5%) were recruited. Colonic neoplasia and CRC were identified in 175 (17.3%) and 114 (11.3%) cases, respectively. Risk scores were assigned to individual factors identified in a logistic regression model of both demographic (age, gender, ethnicity, education level, smoking history, Aspirin use) and clinical symptoms (change in bowel habit, bloody stool, weight loss, appetite loss, lethargy). The risk score for each patient was the sum of their individual risk factors. The AUC of the risk score for colonic neoplasia and CRC was 0.76 (Hosmer-Lemeshow goodness-of-fit statistic of P = 0.745) and 0.83 (Hosmer-Lemeshow goodness-of-fit statistic of P = 0.982), respectively.

CONCLUSION

A simple risk score for colonic neoplasia and CRC may be able to prioritize colonoscopy referrals in symptomatic subjects from a multi-ethnic background. A further study to validate this scoring system is required.

Comparison of the efficacy and safety of sodium phosphate tablets and polyethylene glycol solution for bowel cleansing in healthy Korean adults

PURPOSE

Bowel cleansing is generally regarded as time-consuming and unpleasant among patients. Patients commonly state that bowel preparation provokes more discomfort than the actual colonoscopic examination. The purpose of this study was to compare two regimens of sodium phosphate (NaP) tablets versus polyethylene glycol (PEG) solution for bowel preparation in healthy Korean adults.

MATERIALS AND METHODS

This was a single center, prospective, open-label, investigator-blinded, randomized, controlled-pilot study. A total of 62 healthy Korean subjects were randomly assigned to two groups (NaP vs. PEG). Efficacy, safety, and patient-related outcomes, as well as procedural parameters, were evaluated.

RESULTS

Although there were no significant differences in total Ottawa bowel quality score, fluid scores and the rate of adequate bowel preparation were significantly better in the NaP group than the PEG group. Additionally, the NaP group showed better results regarding patient tolerance, satisfaction, preference, and rate of adverse events than the PEG group. Significant fluctuations in specific serum electrolytes were common and of a greater magnitude in the NaP group than the PEG group. However, these abnormalities were transient and did not result in serious complications and side effects.

CONCLUSION

In this study, NaP tablets were shown to be an effective, well-tolerated, and acceptable regimen for bowel preparation. Also, our study suggests that NaP tablets may be safe and can be used as a bowel cleansing agent in healthy adults undergoing elective colonoscopy. Further multicenter, large scale studies are needed to confirm these findings.

Efficacy and tolerability of low-volume (2 L) versus single- (4 L) versus split-dose (2 L + 2 L) polyethylene glycol bowel preparation for colonoscopy: randomized clinical trial

BACKGROUND AND AIM

To compare the efficacy and tolerability of a low-volume (2-L) polyethylene glycol (PEG) regimen for colonoscopy compared to single (4-L) or split-dose (2-L + 2-L) regimens.

METHODS

In-hospital patients who were candidates for colonoscopy were randomly assigned to: group 1 single-dose (PEG 4 L the day before the study, n = 60); group 2: split-dose (2 L the day before and 2 L on the day of the procedure, n = 61); and group 3: low-volume 2-L PEG solution (the day of the procedure, n = 59). A blinded evaluation of the quality of colonic preparation was assessed by the Boston bowel preparation scale.

RESULTS

Satisfactory bowel preparation of the right colon was more frequently reported for group 3 than for group 1 (70% vs 53%, P = 0.045), in the transverse colon it was 82% versus 69% (P = 0.032), and on the left side of the colon it was 80% versus 67.7% (P = 0.028). Compared to group 2, satisfactory bowel preparation in group 3 was similar in the transverse colon and left colon. Nausea, vomiting, and abdominal discomfort were less frequent in patients of group 3. Patients in group 3 had fewer sleep disorders and fewer hours of sleep loss compared to patients in the other groups.

CONCLUSIONS

Preparation with 2 L caused less abdominal discomfort and fewer sleep disorders. The split dose had a better quality of preparation in the right colon. Both preparations were clearly better than the 4-L preparation.

Split-dose vs same-day reduced-volume polyethylene glycol electrolyte lavage solution for morning colonoscopy

AIM: To compare same-day whole-dose vs split-dose of 2-litre polyethylene glycol electrolyte lavage solution (PEG-ELS) plus bisacodyl for colon cleansing for morning colonoscopy.

METHODS: Consecutive adult patients undergoing morning colonoscopy were allocated into two groups i.e., same-day whole-dose or split-dose of 2-litre PEG-ELS. Investigators and endoscopists were blinded to the allocation. All patients completed a questionnaire that was designed by Aronchick and colleagues to assess the tolerability of the bowel preparation regime used. In addition, patients answered an ordinal five-value Likert scale question on comfort level during bowel preparation. Endoscopists graded the quality of bowel preparation using the Boston bowel preparation scale (BBPS). In addition, endoscopists gave an overall grading of the quality of bowel preparation. Cecal intubation time, withdrawal time, total colonoscopy time, adenoma detection rate and number of adenomas detected for each patient were recorded. Sample size was calculated using an online calculator for binary outcome non-inferiority trial. Analyses was based upon intent-to-treat. Significance was assumed at P-value < 0.05.

RESULTS: Data for 295 patients were analysed. Mean age was 62.0 ± 14.4 years old and consisted of 50.2 % male. There were 143 and 152 patients in the split-dose and whole-dose group, respectively. Split-dose was as good as whole-dose for quality of bowel preparation. The total BBPS score was as good in the split-dose group compared to the whole-dose group [6 (6-8) vs 6 (6-7), P = 0.038]. There was no difference in cecal intubation rate, cecal intubation time, withdrawal time, total colonoscopy time and adenoma detection rate. Median number of adenoma detected was marginally higher in the split-dose group [2 (1-3) vs 1 (1-2), P = 0.010]. Patients in the whole-dose group had more nausea (37.5% vs 25.2%, P = 0.023) and vomiting (16.4% vs 8.4%, P = 0.037), and were less likely to complete the bowel preparation (94.1% vs 99.3%, P = 0.020). Patients in the split-dose group were less likely to refuse the same bowel preparation regime (6.3% vs 13.8%, P = 0.033) and less likely to want to try another bowel preparation regime (53.8% vs 78.9%, P < 0.001).

CONCLUSION: Splitting reduced-volume PEG-ELS for morning colonoscopy is as effective as taking the whole dose on the same morning but is better tolerated and preferred by patients.

Rescue bowel preparation: same day 2 L polyethylene glycol addition, not superior to bisacodyl addition 7 days later

BACKGROUND

The optimal colon-cleansing method after failure of bowel preparation (BP) for colonoscopy has not been established.

AIMS

We aimed to compare BP rescue methods after failed initial BP and to identify risk factors for rescue BP failure.

METHODS

Eighty-five patients with BP failure after 4 L polyethylene glycol (PEG) ingestion were prospectively enrolled from March 2008 to March 2012. A second colonoscopy was performed either on the same day after ingestion of another 2 L PEG (group A) or 1 week later after ingestion of 4 L PEG plus 20 mg oral bisacodyl (group B). Differences between groups in terms of BP quality and risk factors for a poor BP on the second colonoscopy were investigated.

RESULTS

Median patient age was 59 years, 45 were male (52.9 %), and 17 (20 %) had poor BP on the second colonoscopy. For group B, the multivariable-adjusted odds ratio (OR) for poor BP on the second colonoscopy relative to group A was 0.68 (95 % confidence interval [CI], 0.16-2.95). Adequately ingested PEG during the initial colonoscopy was associated with poor BP on the second colonoscopy (OR 4.05; 95 % CI 1.04-15.75). The two groups had similar patient discomfort rates during the second BP.

CONCLUSIONS

The two groups did not differ in rescue BP failure rate. Initial BP failure after adequate consumption of 4 L PEG may be a risk factor for rescue BP failure. A stricter BP regimen should be considered for these patients.

A randomized, endoscopist-blinded, prospective trial to compare the preference and efficacy of four bowel-cleansing regimens for colonoscopy

OBJECTIVES

The superiority of conventional polyethylene glycol (PEG) solution over sodium picosulfate with magnesium citrate (SPMC) for bowel preparation remains controversial. Therefore, this study compared the efficacy, safety, and tolerability of different regimens of SPMC and PEG solution in Koreans, who consume a traditional high-fiber diet.

MATERIALS AND METHODS

A total of 200 outpatients undergoing elective colonoscopy were randomized into four groups receiving different bowel-preparation regimens in a prospective study: 4 L PEG in the morning on the day of colonoscopy, two 2 L split doses of PEG, split doses of 2 SPMC sachets, and split doses of 3 SPMC sachets. Bowel cleansing efficacy was assessed based on the Ottawa bowel preparation scale and the Aronchick scale by endoscopists blinded to treatment, and patients filled out a questionnaire to determine satisfaction.

RESULTS

There was no difference among groups with respect to bowel cleansing grade (Ottawa scale, p = 0.314). Patients in the SPMC groups were less likely to have abdominal fullness, pain, nausea, or vomiting than patients in the PEG groups (p < 0.05). Patients reported SPMC was more palatable than PEG. There were no significant differences among groups with respect to polyp detection rate.

CONCLUSION

SPMC is as effective as conventional high-volume PEG-electrolyte solution in Korean patients. SPMC groups reported superior palatability and tolerability compared to PEG groups.

Detection of colorectal adenoma by narrow band imaging (HQ190) vs. high-definition white light colonoscopy: a randomized controlled trial

OBJECTIVES

The benefits of narrow band imaging (NBI) on enhancing colorectal adenoma detection remain questionable. We tested whether the new generation of NBI (190-NBI), which is twice as bright as the previous version, would improve adenoma detection when compared with high-definition white light (HD-WL) colonoscopy.

METHODS

It was a randomized controlled trial with tandem colonoscopy. We recruited patients who underwent colonoscopy for symptoms, screening, or surveillance. Patients were randomized for the use of either 190-NBI or HD-WL on withdrawal. Tandem colonoscopy was performed by using the same assigned colonoscope and withdrawal method. Lesions detected on first-pass and second-pass examination were used for adenoma detection and miss rates, respectively. The primary outcomes were adenoma and polyp detection rates.

RESULTS

A total of 360 patients were randomized to undergo either 190-NBI or HD-WL colonoscopy. Both the adenoma and polyp detection rates were significantly higher in the 190-NBI group compared with the HD-WL group (adenoma: 48.3% vs. 34.4%, P=0.01; polyps: 61.1% vs. 48.3%, P=0.02). The mean number of polyps detected per patient was higher in the 190-NBI group (1.49% vs. 1.13, P=0.07). There was no significant difference in the adenoma miss rates between the two groups (21.8% vs. 21.2%). Multivariate analysis showed that the use of 190-NBI (odds ratio (OR) 1.85; 95% confidence interval (CI) 1.10-3.12), withdrawal time (OR 1.29; CI 1.19-1.38), patient's age (OR 1.04; CI 1.01-1.06), and male gender (OR 2.38; CI 1.42-3.99) were associated with adenoma detection.

CONCLUSIONS

190-NBI colonoscopy was superior to the conventional HD-WL in detecting colorectal adenomas or polyps, but there was no significant difference in adenoma miss rates.

Bowel preparation for colonoscopy with magnesium sulphate and low-volume polyethylene glycol

BACKGROUND

Patient compliance with bowel cleansing procedures represents one of the most objectionable aspects of colonoscopy. Adverse reactions to the purgative may result in failure to complete the preparation, inadequate visualization of the colon, polyp and even carcinoma miss rate and unwillingness to attend a follow-up colonoscopy. The primary objective of the study was to evaluate the effectiveness of bowel cleansing with magnesium sulphate and low-volume polyethylene glycol (PEG) with electrolytes. The second objective was to evaluate whether bowel cleansing was better in participants scheduled for morning colonoscopies or afternoon colonoscopies.

PATIENTS AND METHODS

Magnesium sulphate mineral water (2 l) and 2 l of low-volume PEG and electrolytes solution were used as our bowel cleansing protocol. A total of 13 914 participants, who participated in the Slovenian colorectal cancer screening programme in the period between 2009 and 2011, were included.

RESULTS

Excellent bowel preparation was achieved in 11 484 (82.61%) participants; 1894 (13.62%) participants had good bowel preparation, 439 (3.16%) participants had fair bowel preparation and 85 (0.61%) participants had poor bowel preparation. Better results were achieved in the afternoon colonoscopies and in younger participant groups (P<0.001). No serious side effects of bowel cleansing were reported.

CONCLUSION

This is the first study to use magnesium sulphate mineral water and PEG plus electrolytes for bowel cleansing. We found excellent bowel cleansing in 82.61% participants and in more participants if colonoscopy was performed in the afternoon.

A pilot study of endoluminal US for stool liquefaction

BACKGROUND

There is a need to cleanse patients who are poorly prepared for colonoscopy safely and efficiently during the procedure to minimize rescheduling. US is already being used in catheter-based intravascular thrombolysis, and time-reversal acoustic (TRA) has been explored in assisting drug delivery to the brain.

OBJECTIVE

To explore the efficacy and safety of a miniaturized endoluminal US device in stool dissolution as a means to salvage poor bowel preparation.

DESIGN

Proof of concept experimental study.

SETTINGS

Animal laboratory.

INTERVENTIONS

Low-frequency US and TRAs.

MAIN OUTCOME MEASUREMENTS

Feasibility, efficacy, and safety of US to liquefy stools ex vivo.

RESULTS

Depending on parameters, such as pulse rate, acoustic intensity, and duration, increases in liquefaction speeds by a factor of 50 and 100 times were obtained. There was a significant difference in weight change between the 20-kHz-treated sample compared with controls (P ≤ .0001). There was no difference in sloughing of mucosa and mechanical injury among the US, water spray, and control groups.

LIMITATIONS

Animal model.

CONCLUSION

Endoluminal US can liquefy stools at acoustic exposure levels that do not damage ex vivo colonic mucosa. Endoluminal US should be able to dissolve stools more rapidly than water spray alone, thereby optimizing colonoscopic evaluation in vivo.

2 L versus 4 L of PEG3350 + electrolytes for outpatient colonic preparation: a randomized, controlled trial

BACKGROUND

Low-volume bowel preparations are ideal to ensure patient compliance, thus enabling high-quality examinations to be achieved.

OBJECTIVES

To examine the bowel-cleansing efficacy and patient tolerability of split-dose 2 L PEG3350 + electrolytes (PEG3350e) with 15 mg bisacodyl versus split-dose 4 L PEG3350e.

DESIGN

Single-blinded, noninferiority, randomized, controlled trial.

SETTING

Single site, university-affiliated tertiary care center.

PATIENTS

A total of 325 consecutive patients undergoing elective outpatient colonoscopy.

INTERVENTION

2 L of PEG3350e with 15 mg bisacodyl versus 4 L of PEG3350e, both given in a split-dose fashion.

MAIN OUTCOME MEASUREMENTS

Efficacy and tolerability of a split dose of 2 L of PEG3350e with 15 mg bisacodyl. Efficacy was assessed by using the Boston Bowel Preparation Scale and Ottawa Bowel Preparation Scale. Patient satisfaction and tolerability were assessed by using a short survey.

RESULTS

A total of 325 patients were included in the intention-to-treat analysis (51% male) with a mean ± standard deviation age of 56 ± 11.2 years. No statistically significant difference in cleanliness was found by using the Boston Bowel Preparation Scale (intention-to-treat, P = .381; per-protocol, P = .387) and the Ottawa Bowel Preparation Scale (intention-to-treat, P = .285; per-protocol, P = .334). Participants receiving 2 L of PEG3350e found the preparation easy to consume and were willing to repeat the procedure more often than the 4-L group (P < .001).

LIMITATIONS

Single-center study looking at outpatient colonoscopies; unable to comment on adenoma detection rate.

CONCLUSIONS

Bowel-cleansing efficacy was similar in both the 2-L and 4-L PEG3350e groups; however, patient tolerability and willingness to repeat preparation were statistically greater with the 2 L of PEG3350e with 15 mg bisacodyl regimen.

Comparison of the Efficacy and Tolerability between Same-day Picosulfate and Split-dose Polyethylene Glycol Bowel Preparation for Afternoon Colonoscopy: A Prospective, Randomized, Investigator-blinded Trial

Background/Aims

In the present study, we evaluated the efficacy and tolerability between same-day bowel preparation protocols using 2 sachets of Picosulfate and a 4 L split-dose polyethylene glycol (PEG) bowel preparation for afternoon colonoscopy.

Methods

The study had a single-center, prospective, randomized, and investigator-blinded, non-inferiority design. We evaluated bowel preparation quality according to the Ottawa scale, patient tolerability, compliance, incidence of adverse events, sleep quality, and polyp/adenoma detection rate.

Results

Among the 196 patients analyzed (mean age, 55.3 years; 50.3% men), 97 received the same-day regimen of 2 sachets of picosulfate (group A) and 99 received the 4 L split-dose PEG regimen (group B). The Ottawa score of the total colon was 4.05±1.56 in group A and 3.80±1.55 in group B (P=0.255). The proportion of patients having adequate bowel preparation in the same-day picosulfate group (61.5%) was slightly less than the 4 L PEG group (71.3%); however, the difference was not statistically significant (P=0.133). Tolerability of the group A regimen was superior to that of the group B regimen (P<0.000). The same-day picosulfate regimen was associated with fewer adverse events, such as abdominal bloating (P=0.037) and better sleep quality (P<0.000).

Conclusions

The same-day picosulfate regimen and the 4 L split-dose PEG regimen had similar efficacy in bowel preparation for afternoon colonoscopy. However, the same-day picosulfate regimen was easier to administer, produced fewer adverse events, and enabled better sleep quality.

Telephone-based re-education on the day before colonoscopy improves the quality of bowel preparation and the polyp detection rate: a prospective, colonoscopist-blinded, randomised, controlled study

BACKGROUND

Despite advances in bowel preparation methods, the quality of bowel preparation in some patients undergoing colonoscopy remains unsatisfactory. The effect of telephone re-education (TRE) on the day before colonoscopy on the quality of bowel preparation and other outcome measures had not been studied.

METHODS

A prospective colonoscopist-blinded study was conducted. All patients received regular instructions during a visit to discuss colonoscopy. Those scheduled for colonoscopy were randomly assigned to receive TRE on the day before colonoscopy (TRE group) for bowel preparation or no TRE (control group). The primary outcome was the rate of adequate bowel preparation. The secondary outcomes included polyp detection rate (PDR), non-compliance with instructions, and willingness to repeat bowel preparation.

RESULTS

A total of 605 patients were randomised, 305 to the TRE group and 300 to the control group. In an intention-to-treat analysis of the primary outcome, adequate preparation was found in 81.6% vs 70.3% of TRE and control patients, respectively (p=0.001). PDR was 38.0% vs 24.7% in the TRE and control group, respectively (p<0.001). Among patients with successful colonoscopy, the Ottawa scores were 3.0±2.3 in the TRE group and 4.9±3.2 in the control group (p<0.001). Fewer patients who showed non-compliance with instructions were found in the TRE group (9.4% vs 32.6%, p<0.001). No significant differences were observed between the two groups with regard to willingness to have a repeat bowel preparation (p=0.409).

CONCLUSIONS

TRE about the details of bowel preparation on the day before colonoscopy significantly improved the quality of bowel preparation and PDR.

Water exchange enhanced cecal intubation in potentially difficult colonoscopy. Unsedated patients with prior abdominal or pelvic surgery: a prospective, randomized, controlled trial

BACKGROUND

Colonoscopy is widely used for management of colorectal diseases. A history of abdominal or pelvic surgery is a well-recognized factor associated with difficult colonoscopy. Although water exchange colonoscopy (WEC) was effective in small groups of male U.S. veterans with such a history, its application in other cultural settings is uncertain.

OBJECTIVE

To investigate the application of WEC in such patients.

DESIGN

Prospective, randomized, controlled, patient-blinded study.

SETTING

Tertiary-care referral center in China.

PATIENTS

Outpatients with prior abdominal or pelvic surgery undergoing unsedated diagnostic, screening, or surveillance colonoscopy.

INTERVENTION

Patients were randomized to examination by either WEC or conventional air colonoscopy (AC).

MAIN OUTCOME MEASUREMENTS

Cecal intubation rate.

RESULTS

A total of 110 patients were randomized to the WEC (n = 55) or AC (n = 55) group. WEC significantly increased the cecal intubation rate (92.7% vs 76.4%; P = .033). The maximum pain scores (± standard deviation) were 2.1 ± 1.8 (WEC) and 4.6 ± 1.7 (AC), respectively (P < .001). Multivariate analysis showed that the colonoscopy method was the only independent predictor of failed colonoscopy (odds ratio 11.44, 95% confidence interval, 1.35-97.09). A higher proportion of patients examined by WEC would be willing to have a repeat unsedated colonoscopy (90.9% vs 72.7%, P = .013).

LIMITATIONS

Single center; unblinded but experienced endoscopists.

CONCLUSION

This randomized, controlled trial confirms that the water exchange method significantly enhanced cecal intubation in potentially difficult colonoscopy in unsedated patients with prior abdominal or pelvic surgery. The lower pain scores and higher proportion accepting repeat of the unsedated option suggest that WEC is promising. It may enhances compliance with colonoscopy in specific populations. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01485133.).

Can mosapride citrate reduce the volume of lavage solution for colonoscopy preparation?

AIM: To evaluate the possibility of reducing the volume of polyethylene glycol (PEG)-electrolyte solution using adjunctive mosapride citrate for colonoscopy preparation.

METHODS: This was a single-center, prospective, randomized, investigator-blinded, non-inferiority study involving 252 patients of both sexes, aged from 20 to 80 years, scheduled for screening or diagnostic colonoscopy in our department. A total of 126 patients was randomized to receive 1.5 L PEG-electrolyte solution plus 15 mg of mosapride (1.5 L group), and 126 received 2 L PEG-electrolyte solution plus 15 mg of mosapride (2 L group). Patients completed a questionnaire on the acceptability and tolerability of the bowel preparation process. The efficacy of bowel preparation was assessed using a 5-point scale based on the Aronchick scale. The primary end point was adequate bowel preparation rates (score of excellent/good/fair) vs (poor/inadequate). Acceptability and tolerability, as well as disease detection, were secondary end points.

RESULTS: A total of 244 patients was included in the analysis. There were no significant differences between the 2 L and 1.5 L groups in age, sex, body mass index, number of previous colonoscopies, and the preparation method used previously. The adequate bowel preparation rates were 88.5% in the 2 L group and 82.8% in the 1.5 L group [95% lower confidence limit (LCL) for the difference = -14.5%, non-inferiority P = 0.019] in the right colon. In the left colon, the adequate bowel preparation rates were 89.3% in the 2 L group and 81.1% in the 1.5 L group (95% LCL = -17.0%, non-inferiority P = 0.066). Compliance, defined as complete (100%) intake of the PEG solution, was significantly higher in the 1.5 L group than in the 2 L group (96.8% vs 85.7%, P = 0.002). The proportion of abdominal distension (none/mild/moderate/severe) was significantly lower in the 1.5 L group than in the 2 L group (36/65/22/3 vs 58/48/18/2, P = 0.040). Within the subgroup who had undergone colonoscopy previously, a significantly higher number of patients in the 1.5 L group than in the 2 L group felt that the current preparation was easier than the previous one (54.1% vs 28.0%, P = 0.001). The disease detection rate was not significantly different between the two groups.

CONCLUSION: Although the 1.5 L group had better acceptability and tolerability, 15 mg of mosapride may be insufficient to compensate for a 0.5-L reduction of PEG solution.

The impact of narrow band imaging for colon polyp detection: a multicenter randomized controlled trial by tandem colonoscopy

BACKGROUND

Previous studies have yielded conflicting results on the adenoma detection rate with narrow band imaging (NBI) compared with white light imaging (WLI). To overcome the confounding factors of these studies, we aimed to evaluate the colonic adenoma detection rate with primary NBI versus that with primary WLI by using consistent NBI system, endoscope, and imaging settings, and experienced colonoscopists.

METHODS

In this multicenter prospective trial, 813 patients were randomized to undergo high-definition, tandem colonoscopy in the right colon with either NBI followed by WLI (NBI-WLI group) or WLI followed by NBI (WLI-NBI group). The NBI settings were fixed at surface structure enhancement level A-5 and adaptive index of hemoglobin color enhancement level 3. All detected polyps were resected or biopsied for histopathological analysis. The primary and secondary outcome measures were the adenoma detection rates and miss rates, respectively, with primary imaging.

RESULTS

The NBI-WLI and WLI-NBI groups comprised 389 and 393 patients, respectively, who met the inclusion criteria. The groups did not differ significantly in age, gender, institution, indication for colonoscopy, bowel preparation, or observation time. The adenoma detection rates of primary NBI and WLI were 42.3 and 42.5 %, respectively [difference not significant (NS)]. The adenoma miss rate was significantly less with primary NBI than with primary WLI (21.3 vs. 27.8 %; p = 0.03).

CONCLUSIONS

NBI does not improve the adenoma detection rate during primary colonoscopy; however, it has a lower miss rate for adenoma lesions in the proximal colon than WLI.

Chronic methadone use, poor bowel visualization and failed colonoscopy: A preliminary study

AIM: To examine effects of chronic methadone usage on bowel visualization, preparation, and repeat colonoscopy.

METHODS: In-patient colonoscopy reports from October, 2004 to May, 2009 for methadone dependent (MD) patients were retrospectively evaluated and compared to matched opioid naive controls (C). Strict criteria were applied to exclude patients with risk factors known to cause constipation or gastric dysmotility. Colonoscopy reports of all eligible patients were analyzed for degree of bowel visualization, assessment of bowel preparation (good, fair, or poor), and whether a repeat colonoscopy was required. Bowel visualization was scored on a 4 point scale based on multiple prior studies: excellent = 1, good = 2, fair = 3, or poor = 4. Analysis of variance (ANOVA) and Pearson χ² test were used for data analyses. Subgroup analysis included correlation between methadone dose and colonoscopy outcomes. All variables significantly differing between MD and C groups were included in both univariate and multivariate logistic regression analyses. P values were two sided, and < 0.05 were considered statistically significant.

RESULTS: After applying exclusionary criteria, a total of 178 MD patients and 115 C patients underwent a colonoscopy during the designated study period. A total of 67 colonoscopy reports for MD patients and 72 for C were included for data analysis. Age and gender matched controls were randomly selected from this population to serve as controls in a numerically comparable group. The average age for MD patients was 52.2 ± 9.2 years (range: 32-72 years) years compared to 54.6 ± 15.5 years (range: 20-81 years) for C (P = 0.27). Sixty nine percent of patients in MD and 65% in C group were males (P = 0.67). When evaluating colonoscopy reports for bowel visualization, MD patients had significantly greater percentage of solid stool (i.e., poor visualization) compared to C (40.3% vs 6.9%, P < 0.001). Poor bowel preparation (35.8% vs 9.7%, P < 0.001) and need for repeat colonoscopy (32.8% vs 12.5%, P = 0.004) were significantly higher in MD group compared to C, respectively. Under univariate analysis, factors significantly associated with MD group were presence of fecal particulate [odds ratio (OR), 3.89, 95% CI: 1.33-11.36, P = 0.01] and solid stool (OR, 13.5, 95% CI: 4.21-43.31, P < 0.001). Fair (OR, 3.82, 95% CI: 1.63-8.96, P = 0.002) and poor (OR, 8.10, 95% CI: 3.05-21.56, P < 0.001) assessment of bowel preparation were more likely to be associated with MD patients. Requirement for repeat colonoscopy was also significant higher in MD group (OR, 3.42, 95% CI: 1.44-8.13, P = 0.01). In the multivariate analyses, the only variable independently associated with MD group was presence of solid stool (OR, 7.77, 95% CI: 1.66-36.47, P = 0.01). Subgroup analysis demonstrated a general trend towards poorer bowel visualization with higher methadone dosage. ANOVA analysis demonstrated that mean methadone dose associated with presence of solid stool (poor visualization) was significantly higher compared to mean dosage for clean colon (excellent visualization, P = 0.02) or for those with liquid stool only (good visualization, P = 0.01).

CONCLUSION: Methadone dependence is a risk factor for poor bowel visualization and leads to more repeat colonoscopies. More aggressive bowel preparation may be needed in MD patients.

Split-dosed MiraLAX/Gatorade is an effective, safe, and tolerable option for bowel preparation in low-risk patients: a randomized controlled study

OBJECTIVES

MiraLAX with Gatorade is a low-volume bowel preparation regimen that has been used widely in community practice and is anecdotally better tolerated than Golytely. Despite its widespread use, there are little data on the efficacy and tolerability of this solution and no safety data in the literature. The primary aim of this study was to compare the efficacy, safety, and tolerability of single-dosed and split-dosed regimens of MiraLAX/Gatorade with Golytely for bowel preparation before colonoscopy.

METHODS

Adults presenting for outpatient colonoscopy were screened for enrollment into this single-blinded randomized controlled trial. Patients with severe cardiac or renal disease and patients with electrolyte abnormalities were excluded. Subjects were randomized into four groups: 4 l Golytely single-dosed (Go-Si), 4 l Golytely split-dosed (Go-Sp), 238 g MiraLAX in 64 oz of Gatorade single-dosed (Mlax-Si), and MiraLAX/Gatorade split-dosed (Mlax-Sp) groups. Laboratory data including complete blood count, comprehensive metabolic panel, and osmolality were collected before the day of bowel preparation and just before the start of colonoscopy. Subjects completed a survey assessing taste and tolerability of the solution. Colonoscopies were recorded using video recording software and de-identified. Colonoscopy videos were evaluated for efficacy of cleansing by two blinded endoscopists. Two validated bowel preparation scales were used to assess bowel cleansing: the Boston Bowel Preparation Scale (BBPS; 0-9 best) and Ottawa Scale (0-14 worst).

RESULTS

A total of 222 patients were evaluated in this study (86.2% male, mean age 59.4). Of these, 57 subjects were randomized to the Go-Si group, 51 to Go-Sp group, 60 to Mlax-Si group, and 54 to Mlax-Sp group. There was no significant difference in age, gender, or timing of colonoscopy between the groups (P>0.05). Mean BBPS scores were: Go-Si=6.07, Go-Sp=8.33, Mlax-Si=6.62, and Mlax-Sp=8.01. Mean Ottawa score for the groups were: Go-Si group=6.77, Go-Sp=4.12, Mlax-Si=6.25, and Mlax-Sp=4.8. Go-Sp resulted in significantly better cleansing than Go-Si (P<0.01). Mlax-Sp resulted in significantly better cleansing than Mlax-Si (P<0.01). There was no significant difference in BBPS between Go-Sp and Mlax-Sp. There were no clinically significant electrolyte changes from baseline in any subject in any group after bowel prep (P>0.05). Subjects rated the taste and overall experience of Mlax/Gatorade preparation better than Golytely (P<0.01). In all, 96.8% of Mlax/Gatorade subjects were willing to repeat the same preparation vs. 75% for Golytely subjects (P<0.01).

CONCLUSIONS

Split-dosed MiraLAX/Gatorade was an effective, safe, and tolerable option for bowel preparation before colonoscopy in the low-risk patients in this study. MiraLAX/Gatorade appears to be more tolerable than Golytely as a bowel cleansing regimen and was the preferred agent by the patients in this study.

Enhancing bowel preparation for colonoscopy: an integrative review

Colorectal cancer is the third most common cancer and second leading cause of cancer-related deaths in the United States. Currently, colonoscopy is considered the gold standard to detect colorectal cancer. Poor bowel preparation in patients undergoing colonoscopy compromises the quality and efficacy of this procedure, affecting patient outcomes and increasing overall costs. With up to 25% of patients undergoing colonoscopy having poor bowel preparation, interventions to enhance the quality of bowel preparations are vital to improving clinical practice. Through an extensive review of the current literature, split-dose bowel preparation regimens appear to be the most well-supported and plausible intervention for meaningful change in efforts to enhance bowel preparation. Several studies of high quality and strength have drawn consistent conclusions that split-dose bowel preparations result in significantly better bowel cleansing than traditional day-prior bowel preparation regimens. Strengths, limitations, gaps in the current literature, and areas for future research are identified, which can help to direct future studies needed to strengthen the evidence and determine further practice initiatives to address the problem of poor bowel preparation for colonoscopy.

New reduced volume preparation regimen in colon capsule endoscopy

AIM: To evaluate the effectiveness of our proposed bowel preparation method for colon capsule endoscopy.

METHODS: A pilot, multicenter, randomized controlled trial compared our proposed “reduced volume method” (group A) with the “conventional volume method” (group B) preparation regimens. Group A did not drink polyethylene glycol electrolyte lavage solution (PEG-ELS) the day before the capsule procedure, while group B drank 2 L. During the procedure day, groups A and B drank 2 L and 1 L of PEG-ELS, respectively, and swallowed the colon capsule (PillCam COLON^® capsule). Two hours later the first booster of 100 g magnesium citrate mixed with 900 mL water was administered to both groups, and the second booster was administered six hours post capsule ingestion as long as the capsule had not been excreted by that time. Capsule videos were reviewed for grading of cleansing level.

RESULTS: Sixty-four subjects were enrolled, with results from 60 analyzed. Groups A and B included 31 and 29 subjects, respectively. Twenty-nine (94%) subjects in group A and 25 (86%) subjects in group B had adequate bowel preparation (ns). Twenty-two (71%) of the 31 subjects in group A excreted the capsule within its battery life compared to 16 (55%) of the 29 subjects in group B (ns). Of the remaining 22 subjects whose capsules were not excreted within the battery life, all of the capsules reached the left side colon before they stopped functioning. A single adverse event was reported in one subject who had mild symptoms of nausea and vomiting one hour after starting to drink PEG-ELS, due to ingesting the PEG-ELS faster than recommended.

CONCLUSION: Our proposed reduced volume bowel preparation method for colon capsule without PEG-ELS during the days before the procedure was as effective as the conventional volume method.

Split-dose picosulfate, magnesium oxide, and citric acid solution markedly enhances colon cleansing before colonoscopy: a randomized, controlled trial

BACKGROUND

Picosulfate, magnesium oxide, and citric acid solution is a small-volume agent for colon cleansing before colonoscopy that is extremely well tolerated by patients, safe, and efficacious. Studies of other cleansing agents have suggested that split-dose regimens may further enhance efficacy.

OBJECTIVE

To examine whether split-dosing of picosulfate, magnesium oxide, and citric acid solution increases bowel cleansing efficacy while maintaining tolerability and safety.

DESIGN

Prospective, randomized, single-blinded, controlled trial.

SETTING

Outpatient tertiary care center.

PATIENTS

A total of 236 patients underwent colonoscopy (mean age 56 years, 53.8% female).

INTERVENTIONS

Patients in the traditional arm (n = 123) consumed 1 sachet of solution at 5:00 pm and 10:00 pm the night before the colonoscopy. Patients in the split-dose arm (n = 127) consumed 1 sachet at 7:00 pm the night before and another sachet 4 hours before their colonoscopy appointment.

MAIN OUTCOME MEASUREMENTS

Ottawa Bowel Preparation Scale (OBPS) score, Aronchick score, safety, tolerability.

RESULTS

The 113 and 109 patients in the split-dose and traditional arms, respectively, had OBPS scores for analysis. Overall, the OBPS scores in the split-dose group were significantly improved compared with the traditional dose group (4.05 vs 5.51, P < .001). This was mostly attributed to improvements in right-sided colon cleansing (1.22 in split-dose vs 2.14 in traditional arm, P < .001). Both regimens were well tolerated by patients, and no safety issues were identified.

LIMITATIONS

This was a single-center study. Disturbances in sleep related to the preparation were not assessed.

CONCLUSIONS

The split-dose regimen of picosulfate, magnesium oxide, and citric acid solution is superior to the traditional dosing regimen for colon cleansing before colonoscopy. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT00885274.).

Timing and frequency of bowel activity in patients ingesting sodium picosulphate/magnesium citrate and adjuvant bisacodyl for colon cleansing before colonoscopy

BACKGROUND

Despite the wealth of research investigating bowel cleansing efficacy, there are very little data on the timing or frequency of bowel movements after each agent is ingested.

OBJECTIVE

To examine the effect of each component of a three-day combined sodium picosulphate⁄magnesium citrate (PSLX) and bisacodyl regimen on the timing and frequency of bowel activity in patients undergoing colonoscopy.

METHODS

Outpatients booked for colonoscopy were asked to complete a diary of their bowel preparation that tracked the timing of bowel movements. Bowel preparation quality was assessed using the Ottawa Bowel Preparation Scale. Bowel activity was compared with baseline and correlated with colon cleansing. Subgroup analysis was performed examining the effect of timing of the procedure and split-dose regimens.

RESULTS

One hundred patients undergoing colon cleansing received bisacodyl 10 mg at 17:00 three days and two days before the day of colonoscopy. In one group, both sachets of PSLX were given the night before colonoscopy, while the second group, whose colonoscopies were scheduled after 11:00, ingested one sachet the night before and the second sachet at 06:00 on the day of colonoscopy. Patients had a mean of 1.7 bowel movements per day in the seven days before starting the cleansing regimen. Both doses of bisacodyl tablets resulted in a significant increase in the mean number of bowel movements compared with baseline (3.3⁄day first dose; 3.8⁄day second dose [P=0.03 and 0.001, respectively]). Each dose of PSLX also resulted in a significant increase in bowel movement frequency compared with baseline, with means of 4.4, 6.3 and 4.5 bowel movements after each dose. The mean time to the final bowel movement following the second sachet of PSLX was 8.9 h when taken the night before, and 3.9 h when taken the morning of the procedure. Bowel preparation quality significantly correlated with bowel frequency when total bowel movements were considered and when only the effects of bisacodyl were accounted for (P<0.01 for each).

DISCUSSION

These data demonstrate that the addition of bisacodyl before PSLX ingestion has a significant additive effect on bowel frequency and correlates with bowel cleansing quality. The timing of the resulting bowel movements have practical implications for sleep and travel times to endoscopy suites.

Improving protection against proximal colon cancer by colonoscopy

Colonoscopy protection against proximal cancer can be achieved, but the level of protection has thus far been less than left colon protection. Improved proximal protection begins with effective right colon bowel preparation, best achieved by split dosing the preparation regimen. Cecal intubation in screening examinations should exceed 95%, and must be documented by photography. Examiners must be proficient in detection of subtle right colon lesions, including serrated lesions as well as flat and depressed adenomas. Effective examination should be demonstrated by meeting recommended targets for adenoma detection.