Meta-analysis and cost comparison of polyethylene glycol lavage versus sodium phosphate for colonoscopy preparation

Risk Factors Asscociated with Hypokalemia during Postanesthesia Recovery and Its Impact on Outcomes in Gynecological Patients: A Propensity Score Matching Study

OBJECTIVE

This study aimed to explore the risk factors and outcomes of hypokalemia during the recovery period from anesthesia in the gynecological population.

METHODS

This retrospective cohort study included 208 patients who underwent gynecological surgery at our institution between January 2021 and March 2022. Data were collected for each patient, including demographics, disease status, surgical data, and clinical information. Preoperative bowel preparation, postoperative gastrointestinal function, and electrolyte levels were compared between the two groups using propensity score matching (PSM).

RESULTS

The incidence of hypokalemia (serum potassium level <3.5 mmol/L) during the recovery period from anesthesia was approximately 43.75%. After PSM, oral laxative use (96.4% vs. 82.4%, P=0.005), the number of general enemas (P=0.014), and the rate of ≥2 general enemas (92.9% vs. 77.8%, P=0.004) were identified as risk factors for hypokalemia, which was accompanied by decreased PaCO2 and hypocalcemia. There were no significant differences in postoperative gastrointestinal outcomes, such as the time to first flatus or feces, the I-FEED score (a scoring system was created to evaluate impaired postoperative gastrointestinal function), or postoperative recovery outcomes, between the hypokalemia group and the normal serum potassium group.

CONCLUSION

Hypokalemia during postanesthesia recovery period occurred in 43.75% of gynecological patients, which resulted from preoperative mechanical bowel preparation; however, it did not directly affect clinical outcomes, including postoperative gastrointestinal function, postoperative complications, and length of hospital stay.

Colonic bowel prep and body mass index: does one size fit all? A multi-centre review

PURPOSE

To investigate whether body mass index (BMI) is a risk factor for inadequate bowel preparation in elective colonoscopy. The null hypothesis being BMI does not affect bowel preparation adequacy.

METHODS

A retrospective cohort study of all participants with complete medical records who had an elective colonoscopy was conducted across three tertiary teaching hospitals in Perth, Western Australia, from January 2016 to July 2019. Participants were separated into BMI subgroups of healthy weight, overweight and obese (≥ 30 kg/m²). Data were extracted from medical records, colonoscopy and histopathology reports and were analysed using SPSS v.27.

RESULTS

Of the 1082 cases analysed, 52.7% (n = 570) were male. The median age was 61 (range 18-85 years). The median BMI was 27.8 (range 20-52). The median procedure time is 28 (range 2-69 min). Routine follow-up was the clinical indication for 65% of colonoscopy procedures undertaken during the study period. Multivariate logistic regression, controlled for statistically insignificant confounders of age, type of bowel preparation agent, grade of the endoscopist, the indication for procedure and year of procedure, showed that being obese was significantly and independently associated with inadequate bowel preparation (OR 2.0, 95% CI (1.4-2.9) p < 0.001). Another significant factor was male (OR 1.6, 95% CI (1.2-2.1) p = 0.002).

CONCLUSION

This study shows that obese patients are more likely to have inadequate bowel preparation at colonoscopy. Given the increased complication rates and health care costs associated with repeating colonoscopies and the increased risk of colorectal cancer in obese patients, it may be worth tailoring a more extensive bowel preparation regimen to ensure adequate visualisation of the colonic mucosa on the first attempt.

Electrolyte disturbances after bowel preparation for colonoscopy: Systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

We conducted a systematic review and meta-analysis of population-based studies to explore pooled prevalence and magnitude of electrolyte changes after bowel preparation for colonoscopy based on the most recent guidelines.

PATIENTS AND METHODS

PubMed and Cochrane were queried for population-based studies examining changes in electrolyte values after bowel preparation, published by July 1, 2021. We report prevalences of serum hypokalemia, hyponatremia, hyperphosphatemia, and hypocalcemia after bowel preparation and changes in mean electrolyte values after vs. before bowel preparation using sodium phosphate (NaP) and polyethylene glycol (PEG).

RESULTS

Thirteen studies met the inclusion criteria; 2386 unique patients were included. Overall, hypokalemia was found in 17.2% (95% CI 6.7, 30.9) in the NaP group vs. 4.8% (95% CI 0.27, 13.02) in the PEG group. The magnitude of potassium decrease after NaP bowel preparation was significantly increased compared to PEG (mean difference -0.38; 95% CI -0.49 to -0.27, P < 0.001). No study reported on major complications.

CONCLUSIONS

Hypokalemia was found in 17.2% of patients after bowel preparation with NaP and in 4.8% of patients with PEG, a finding that is clinically relevant with respect to choosing the type of bowel preparation. The magnitude of the potassium decrease after NaP was significantly higher compared to PEG. These data provide the evidence that supports the recommendation of the European Society of Gastrointestinal Endoscopy against routine use of NaP for bowel preparation.

Noninferiority clinical trial comparing the bowel cleansing efficacy of sodium phosphate tablets (Quiklean®) with a polyethylene glycol/bisacodyl kit

BACKGROUND

Efficient bowel cleansing is essential for a successful colonoscopy, but the ideal cleansing agent, volume, and pharmaceutical dosage form have yet to be determined. Small-volume cleansers enhance patient compliance.

AIM

To compare the bowel cleansing efficacy of 32-tablet sodium phosphate (Quiklean^®) with 2-L polyethylene glycol (PEG)/bisacodyl (Klean-Prep/ Dulcolax^®) under identical dietary recommendations.

METHODS

This multicenter, randomized, parallel-group, noninferiority clinical trial enrolled 472 outpatients, randomized 456 subjects, and scheduled 442 subjects to undergo colonoscopy (Quiklean^® = 222 and Klean-Prep/Dulcolax^® = 220). After bowel preparation, a colonoscopist performed the colonoscopy with video recorded for rating. The primary efficacy endpoint was the bowel cleansing quality using the Aronchick Scale. The secondary endpoints were the bowel cleansing efficacy of three colon segments, tolerability and acceptability, safety using the Ottawa bowel preparation scale, questionnaires by subjects, and monitoring of adverse events.

RESULTS

Success rates (Excellent + Good) of the bowel cleansing quality by Aronchick Scale were 98.6% (n = 205) and 97.6% (n = 204) in the Quiklean^® and Klean-Prep/Dulcolax^® groups, respectively. Quiklean^® demonstrated noninferiority over Klean-Prep/Dulcolax^® in colon cleansing efficacy. Quicken showed better tolerability and acceptability in the overall experience (was rated as excellent; 24.0% vs 17.2%; P = 0.0016) and the taste of the study preparation (was rated as excellent, 23.1% vs 13.4%; P < 0.0001) than Klean-Prep/Dulcolax^®. Safety profiles did not differ between the two groups. Our data indicate that Quiklean^® is an adequate, well-tolerated bowel cleansing preparation compared with the standard comparator Klean-Prep/Dulcolax^®.

CONCLUSION

Quiklean^® is sodium phosphate tablets available on Taiwan’s market for bowel preparation; it potentially offers patients an alternative to standard large-volume bowel preparation regimens and may, therefore, increase positive attitudes toward colonoscopies and participation rates.

Efficacy and Tolerability of Prucalopride in Bowel Preparation for Colonoscopy: A Systematic Review and Meta-Analysis

INTRODUCTION

Adequate bowel preparation is a vital determinant for the success of colonoscopy. However, individuals who undergo bowel preparation for colonoscopy can experience major discomfort. To solve this problem, adding prucalopride to the prepared solution may reduce intake volume, decreasing discomfort and side effects. We performed meta-analyses and systematic review of available randomized controlled trials.

METHODS

Meta-analyses were conducted to evaluate the overall relative risk and 95% confidence intervals in the combined studies for the assessment of primary outcome, which is the efficacy of bowel preparation with the addition of prucalopride.

RESULTS

Four randomized controlled trials involving 581 patients were included. When data were pooled for all patients in two non-inferiority studies, no significant difference in the quality of bowel preparation was observed between patients receiving prucalopride plus bowel preparation solution at a lower volume and those receiving the existing solution (relative risk: 0.94; 95% confidence interval: 0.86-1.03). The effects of prucalopride on acceptability, adverse events, adenoma detection rate, and polyp detection rate did not significantly differ from those of traditional solutions.

CONCLUSIONS

The combination of prucalopride and bowel preparation solution at a lower volume has similar effects on bowel preparation, and its use did not increase the occurrence of adverse effects.

A Randomized Trial Comparing the Bowel Cleansing Efficacy of Sodium Picosulfate/Magnesium Citrate and Polyethylene Glycol/Bisacodyl (The Bowklean Study)

Bowel cleansing is essential for a successful colonoscopy, but the ideal clearing agent and the volume have yet to be determined. A small-volume cleanser is important for patient compliance. This study aimed to compare the bowel cleansing efficacy, safety, tolerability, and acceptability of a 300-mL small-volume sodium picosulfate/magnesium citrate (PSMC) preparation-Bowklean with one 2-L polyethylene glycol (PEG)/bisacodyl-Klean-Prep/Dulcolax preparation under identical dietary recommendations. This multicenter, randomized, parallel-group, pre-specified noninferiority study enrolled 631 outpatients scheduled to undergo colonoscopy (Bowklean = 316 and Klean-Prep/Dulcolax = 315). After bowel preparation, an independent evaluator blinded to the subject's treatment allocation rated the quality of the colon cleansing. Efficacy was evaluated using the Aronchick Scale and Ottawa Bowel Preparation Scale (OPBS). Safety was assessed by monitoring adverse events. Tolerability and acceptability were measured via a patient questionnaire. Bowklean was non-interior to Klean-Prep/Dulcolax in overall colon cleansing but was associated with significantly better preparation quality. Notably, Bowklean was associated with significantly greater tolerability and acceptability of bowel preparations than Klean-Prep/Dulcolax. Safety profiles did not differ significantly between the groups. Our data indicate that Bowklean is a more effective and better-tolerated bowel cleansing preparation before colonoscopy than Klean-Prep/Dulcolax. Bowklean may therefore increase positive attitudes toward colonoscopies and participation rates.

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

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

Efficacy, safety, and tolerability of a ready-to-drink bowel preparation: subanalysis by age from a phase III, assessor-blinded study

BACKGROUND

The incidence and mortality of colorectal cancer (CRC) increase with age and, therefore, it is recommended that adults undergo regular CRC screening, ideally by colonoscopy, with some new guidelines recommending screening begin at 45 years. Effective bowel preparation is a critical step to a successful colonoscopy. Of concern is that older adults may have poorer quality of bowel preparation or reduced tolerability for the bowel preparation. Here, we performed a post hoc secondary analysis for the effect of age on the efficacy, tolerability, and safety of ready-to-drink sodium picosulfate, magnesium oxide, and citric acid (SPMC oral solution) bowel preparation.

METHODS

A phase III, randomized, assessor-blinded, multicenter, non-inferiority study was conducted comparing split-dose, low-volume SPMC oral solution with split-dose, low-volume sodium picosulfate, magnesium oxide, and citric acid powder for oral solution. A post hoc secondary analysis was performed to assess efficacy, safety, and tolerability of SPMC oral solution by age group (<50 years, 50-64 years, ⩾65 years). The prespecified primary efficacy endpoint ('responders') was the proportion of participants with 'excellent' or 'good' ratings on a modified Aronchick Scale (AS). Secondary efficacy outcomes were the quality of cleansing of the right colon as assessed by the Boston Bowel Preparation Scale (BBPS); as well as selected findings from the Mayo Clinic Bowel Prep Tolerability Questionnaire. Safety assessments included adverse events (AEs) and laboratory evaluations.

RESULTS

Within age groups, at least 83.9% of participants were responders by the AS, and at least 91.1% of participants were responders by the BBPS in the right colon. On both scales, responder rates were highest in the youngest age group and decreased with increasing age. Greater than 88% of participants in any age group found the preparation 'easy' or 'acceptable' to ingest, with rates of 'easy' being highest in the oldest age group. No new safety signals were seen in any age group. The most commonly reported drug-related, treatment-emergent AEs were, by ascending age group, nausea (7.0%, 3.2%, 0.8%), headache (4.2%, 2.8%, 1.6%) and vomiting (2.8%, 1.2%, 0.8%).

CONCLUSION

Ready-to-drink SPMC oral solution showed good efficacy of overall colon cleansing and tolerability in adults across different age groups, including those ⩾65 years.ClinicalTrials.gov identifier: NCT03017235.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

AIMS

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

PATIENTS AND METHODS

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

RESULTS

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

CONCLUSION

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

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.

Mechanical colon cleansing for screening colonoscopy: A randomized controlled trial

OBJECTIVE

Effective screening colonoscopy depends on the quality of colon preparation. This study aimed to compare pulsed irrigation evacuation (PIE), polyethylene glycol (PEG) and sodium phosphate colon preparations.

METHODS

Outpatients at a VA hospital were randomized using sealed envelopes. Preparations consisted of polyethylene glycol 4L, Fleet sodium phosphate 90 mL with four to six glasses water twice daily and 296 mL of magnesium citrate in the evening with PIE prior to colonoscopy. Colon cleansing was assessed blindly using a five-point scale: 0 (very poor) to 4 (excellent).

RESULTS

Altogether 391 patients participated in the study (129 in the PEG group, 127 in the sodium phosphate and 135 in the PIE group), with a mean age of 62 years, of whom 75% were men. PIE and sodium phosphate were superior to PEG: median cleansing scored 4 (excellent) versus 3 with PEG (P < 0.01). Inadequate preparations were more common with PEG than PIE (18% vs 5%) (P < 0.01). Side-effects included vomiting: 37% in the sodium phosphate group versus 5% in the PEG and 2% in the PIE groups (P < 0.01). The three preparations were judged intolerable in ≤ 5%.

CONCLUSIONS

PIE and sodium phosphate are superior to PEG for colon preparations. PIE is the preferred preparation for those at high risk of unsatisfactory preparations or with unsatisfactory traditional preparations.

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.

Improving bowel preparation for colonoscopy in a cost effective manner

Colonoscopy is a key investigation used to exclude large bowel pathologies including surveillance for CRC (Colorectal cancer) Poor bowel preparation (bowel prep) is one of the most important factors affecting its diagnostic yield. Different formulations of bowel prep are currently in use depending upon patient tolerance, indication & co-morbidities. In University Hospital Llandough we retrospectively reviewed the outcome of colonoscopies performed over period of 3 months, in relation to the type and outcome of bowel preparations used. We implemented a change of patient instruction and pre-assessment of bowel preparation prescribed. We repeated the same measurements over 3 different cycles on 3 different occasions and compared the outcome.

We noticed that quality of bowel preparation noticeably improved from 80% to almost 93% if patients were given appropriate advice in a written format, prior to procedure. In addition to improvement in the quality of assessment & reducing the number of repeat procedures, by changing the bowel preparation product and postage methods we estimated savings of almost £150,000 for the trust in a year.

LONGER CECUM INSERTION TIME AND MORE INADEQUATE COLONIC PREPARATION IN PATIENTS WITH ACROMEGALY: IS A DIFFERENT COLONOSCOPY PREPARATION NEEDED?

Purpose

To investigate whether there is a difference between acromegalic and non-acromegalic cases in terms of bowel preparation and colonoscopic intervention.

Methods

Patients with controlled and uncontrolled acromegaly and as a control group (CG) patients without acromegaly between January 2010 and March 2014 were included. Groups were compared regarding adequacy of bowel preparation, cecal insertion time (CIT) and colonoscopy results.

Results

Fifty-nine patients with acromegaly (controlled n=30, uncontrolled n=29) and 73 age and gender matched volunteers without acromegaly were evaluated. CIT in cases with controlled, uncontrolled acromegaly cases and in CG was 5.33 [4.00-6.00], 7.00 [4.91-11.31], and 3.10 [2.35-4.65] minutes, respectively (p<0.001). Cases in CG had shorter CIT compared to controlled and uncontrolled acromegaly cases ( p=0.014 and p<0.001, respectively). There was no significant difference regarding CIT between controlled and uncontrolled acromegaly cases (p=0.247). Six (20%) of controlled acromegaly patients, 10 (35%) of uncontrolled acromegaly patients and three (4%) of CG had inadequate bowel cleansing (p<0.001). Although statistically insignificant, cases with inadequate bowel cleansing had tendency towards having prolonged CIT in comparison to cases with adequate bowel cleansing (6.00 [3.87-9.00] and 4.16 [2.95-5.70] minutes, respectively, p=0.07).

Conclusion

Inadequate bowel cleansing is one of the main problems encountered during colonoscopic investigation/surveillance in acromegalic patients. Therefore, a different protocol for colonoscopy preparation may be needed for these cases.

Diagnostic value of computed tomography colonography (CTC) after incomplete optical colonoscopy

INTRODUCTION

This study evaluated the role of computed tomography colonography (CTC) in patients who previously underwent incomplete optical colonoscopy (OC). We analyzed the impact of colonic lesions in intestinal segments not studied by OC and extracolonic findings in these patients.

METHODS

Between January 2014 and May 2015, 61 patients with a history of abdominal pain and incomplete OC examination were studied by CTC. CTCs were performed by 320-row CT scan in both the supine and the prone position, without intravenous administration of contrast medium. In all patients both colonic findings and extracolonic findings were evaluated.

RESULTS

Among the study group, 24 CTC examinations were negative for both colonic and extracolonic findings while 6 examinations revealed the presence of both colonic and extracolonic findings. In 24 patients CTC depicted colonic anomalies without extracolonic ones, while in 7 patients it showed extracolonic findings without colonic ones.

DISCUSSION

CTC is a noninvasive imaging technique with the advantages of high diagnostic performance, rapid data acquisition, minimal patient discomfort, lack of need for sedation, and virtually no recovery time. CTC accurately allows the evaluation of the nonvisualized part of the colon after incomplete OC and has the distinct advantage to detect clinically important extracolonic findings in patients with incomplete OC potentially explaining the patient's symptoms and conditioning their therapeutic management.

CONCLUSION

CTC accurately allows the assessment of both colonic and extracolonic pathologies representing a useful diagnostic tool in patients for whom complete OC is not achievable.

Impact of bowel preparation type on the quality of colonoscopy: a multicenter community-based study

Background

High-quality bowel preparation is crucial for achieving the goals of colonoscopy. However, choosing a bowel preparation in clinical practice can be challenging because of the many formulations. This study aims to assess the impact the type of bowel preparation on the quality of colonoscopy in a community hospital setting.

Methods

A retrospective, observational study was conducted utilizing a colonoscopy screening/surveillance database in central Illinois during the period of January 1, 2010, to March 31, 2014. Patients without bowel preparation assessment were excluded from this study. Controlling for the confounders, generalized linear models were used to estimate the adjusted impact [odds ratio (OR)] of bowel preparation type on the quality of preparation (excellent, good, fair, and poor), and on the detection of advanced adenoma. The association between the time of withdrawal after insertion and the quality of preparation was also examined using a linear model.

Results

A total of 28,368 colonoscopies; half the patients were male, and the average age was 61±9 years. Polyethylene glycol (PEG) was used in the majority (70.2%) of bowel preparations, followed by sodium sulfate (21.4%), sodium phosphate (2.5%), magnesium sulfate (0.4%), and others. Compared with PEG, magnesium sulfate had a poorer quality of bowel preparations (OR=0.6, 95% CI 0.4–0.9; p<0.05), whereas the quality of bowel preparation was significantly improved by using sodium sulfate (OR=5.7, 95% CI 5.4–6.1; p<0.001) and sodium phosphate (OR=2.1, 95% CI 1.8–2.5; p<0.001). For those who had adequate bowel preparation, the better quality of preparation significantly increased the detection rate of advanced adenoma (5.0, 3.6, and 2.9% for excellent, good, and fair, respectively).

Conclusion

When possible, sodium sulfate–based preparations should be recommended in the community setting for colonoscopy because of their high quality of bowel preparation.

Sodium Picosulfate with Magnesium Citrate (SPMC) Plus Laxative Is a Good Alternative to Conventional Large Volume Polyethylene Glycol in Bowel Preparation: A Multicenter Randomized Single-Blinded Trial

Background/Aims

We investigated whether sodium picosulfate with magnesium citrate (SPMC) plus bisacodyl compares favorably with conventional polyethylene glycol (PEG) with respect to bowel cleansing adequacy, compliance, and safety.

Methods

We performed a multicenter, prospective, single-blinded study in outpatients undergoing daytime colonoscopies. Patients were randomized into a split preparation SPMC/bisacodyl group and a conventional split PEG group. We compared preparation adequacy using the Boston bowel preparation scale (BBPS), ease of use using a modified Likert scale (LS), compliance/satisfaction level using a visual analogue scale (VAS), and safety by monitoring adverse events during the colonoscopy between the two groups.

Results

A total of 365 patients were evaluated by intention to treat (ITT) analysis, and 319 were evaluated by per protocol (PP) population analysis (153 for SPMC/bisacodyl, 166 for PEG). The mean total BBPS score was not different between the two groups in both the ITT and PP analyses (p>0.05). The mean VAS score for satisfaction and LS score for the ease of use were higher in the SPMC/bisacodyl group (p<0.001). The adverse event rate was lower in the SPMC/bisacodyl group than in the PEG group (p<0.05).

Conclusions

The SPMC/bisacodyl treatment was comparable to conventional PEG with respect to bowel preparation adequacy and superior with respect to compliance, satisfaction, and safety.

Colorectal cancer screening and surveillance in the elderly: updates and controversies

Colorectal cancer is common worldwide, and the elderly are disproportionately affected. Increasing age is a risk factor for the development of precancerous adenomas and colorectal cancer, thus raising the issue of screening and surveillance in older patients. Elderly patients are a diverse and heterogeneous group, and special considerations such as comorbid medical conditions, functional status and cognitive ability play a role in deciding on the utility of screening and surveillance. Colorectal cancer screening can be beneficial to patients, but at certain ages and under some circumstances the harm of screening outweighs the benefits. Increasing adverse events, poorer bowel preparation and more incomplete examinations are observed in older patients undergoing colonoscopy for diagnostic, screening and surveillance purposes. Decisions regarding screening, surveillance and treatment for colorectal cancer require a multidisciplinary approach that accounts not only for the patient’s age but also for their overall health, preferences and functional status. This review provides an update and examines the challenges surrounding colorectal cancer diagnosis, screening, and treatment in the elderly.

Colon Cleansing for Colonoscopy in Patients with Ulcerative Colitis: Efficacy and Acceptability of a 2-L PEG Plus Bisacodyl Versus 4-L PEG

BACKGROUND

Low-volume preparations are gaining attention for higher acceptability but have been never evaluated in IBD. We compare the efficacy, safety, and tolerability of a 2-L PEG with a 4-L PEG solution in patients with ulcerative colitis.

METHODS

This is a multicenter, randomized, single-blind study. Adult outpatients with ulcerative colitis undergoing colonoscopy received either 2-L PEG plus bisacodyl or 4-L PEG. Bowel cleansing was assessed using the Ottawa Scale and rated as adequate if the score was ≤2 in each colon segment. Patient acceptance, satisfaction, and related symptoms were recorded.

RESULTS

Preparation was adequate in 80% of the 211 patients without any differences between groups. Mean Ottawa scores for whole and right colon were similar in the 2 groups. As concern tolerability, 83% patients in 2-L PEG arm and 44.8% in 4-L PEG arm reported no or mild discomfort (P < 0.0001) and 94.3% and 61.9% expressed their willingness to repeat the preparation (P < 0.001). Palatability was better with 2-L PEG, whereas related symptoms occurred more frequently with 4-L PEG. Regardless of preparation, split dosage was associated with better cleansing. Further predictors of poor cleansing were moderate/severe discomfort during preparation and more than 6 hours between end of preparation and colonoscopy. Extension and severity of colitis did not influence quality of preparation.

CONCLUSIONS

Low-volume PEG is not inferior to 4-L PEG for bowel cleansing in ulcerative colitis, but it is better tolerated and accepted. The time interval from solution intake and colonoscopy is the most important factor affecting quality of cleansing in ulcerative colitis.

Colorectal cancer of the elderly

OPINION STATEMENT

Colorectal cancer (CRC) disproportionately affects the elderly. Older age is a strong risk factor for both the development of precancerous adenomas and CRC, thus raising the issue of screening and surveillance in older patients. However, screening and surveillance decisions in the elderly can be complex and challenging. Elderly patients are a diverse and heterogeneous group and special considerations such as co-morbid medical conditions, functional status, and cognitive ability play a role in one's decisions regarding the utility of screening and surveillance. Such considerations also play a role in factors related to screening modalities, such as colonoscopy, as well as CRC treatment options and regimens. This review addresses many of the unique factors associated with CRC of the elderly and critically examines many of the controversies and challenges surrounding CRC in older patients.

A meta-analysis of randomized controlled trials of low-volume polyethylene glycol plus ascorbic acid versus standard-volume polyethylene glycol solution as bowel preparations for colonoscopy

BACKGROUND

Standard-volume polyethylene glycol (PEG) gut lavage solutions are safe and effective, but they require the consumption of large volumes of fluid. A new lower-volume solution of PEG plus ascorbic acid has been used recently as a preparation for colonoscopy.

AIM

A meta-analysis was performed to compare the performance of low-volume PEG plus ascorbic acid with standard-volume PEG as bowel preparation for colonoscopy.

STUDY

Electronic and manual searches were performed to identify randomized controlled trials (RCTs) that compared the performance of low-volume PEG plus ascorbic acid with standard-volume PEG as bowel preparation for colonoscopy. After a methodological quality assessment and data extraction, the pooled estimates of bowel preparation efficacy during bowel cleansing, compliance with preparation, willingness to repeat the same preparation, and the side effects were calculated. We calculated pooled estimates of odds ratios (OR) by fixed- and/or random-effects models. We also assessed heterogeneity among studies and the publication bias.

RESULTS

Eleven RCTs were identified for analysis. The pooled OR for preparation efficacy during bowel cleansing and for compliance with preparation for low-volume PEG plus ascorbic acid were 1.08 (95% CI = 0.98-1.28, P = 0.34) and 2.23 (95% CI = 1.67-2.98, P<0.00001), respectively, compared with those for standard-volume PEG. The side effects of vomiting and nausea for low-volume PEG plus ascorbic acid were reduced relative to standard-volume PEG. There was no significant publication bias, according to a funnel plot.

CONCLUSIONS

Low-volume PEG plus ascorbic acid gut lavage achieved non-inferior efficacy for bowel cleansing, is more acceptable to patients, and has fewer side effects than standard-volume PEG as a bowel preparation method for colonoscopy.

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.

Effects of the addition of high-dose vitamin C to polyethylene glycol solution for colonic cleansing: A pilot study in healthy volunteers

BACKGROUND

Polyethylene glycol (PEG) solutions, with or without osmotic agents, are used to empty the large intestine before procedures such as colonoscopy or colonic surgery. Data concerning the effectiveness of vitamin C as an ingredient in colonic preparations are scant.

OBJECTIVE

The aim of this article was to assess the effectiveness, acceptability, and tolerability of 6 preparations of a standard PEG electrolyte solution containing different doses of PEG, vitamin C (as an osmotic agent), and sodium sulfate in colonic cleansing.

METHODS

This double-blind, randomized, 2-period crossover study was conducted at the Lariboisière Hospital, Paris, France. Healthy adult volunteers were randomly assigned to receive 2 of 6 colonic cleansing preparations, each containing different doses of PEG (100 or 125 g/L), vitamin C (0, 5, or 10 g/L, in the form of sodium ascorbate, ascorbic acid, or a mixture of both), and sodium sulfate (5 or 7.5 g/L), diluted in water to a volume of 2 L. Study drug administration was separated by a washout period of 7 to 15 days, after which the volunteers received an alternate preparation. Stools were collected for 10 hours after the start of solution ingestion. The primary efficacy end point was stool volume. Secondary end points included acceptability of taste, assessed using a 100-mm visual analog scale (VAS) (0 = excellent to 100 = execrable), taste criteria (saltiness, acidity, and sweetness, assessed on a 4-point Likert-type scale [0 = very pleasant to 3 = intolerable]) and tolerability (clinical effects [changes in body weight, blood pressure, heart rate, and nausea and vomiting] and biologic effects [changes in serum electrolytes, creatinine, hematocrit, and ascorbic acid]).

RESULTS

Thirty volunteers (15 men, 15 women; mean [SD] age, 29.8 [8.2] years [range, 20-45 years]) were enrolled and completed the study. Mean (SD) stool volume obtained with preparations containing 10 g/L of vitamin C did not differ significantly from the volume obtained without vitamin C (2.54 [0.54] L vs 1.93 [0.62] L; 95% CI, -0.13 to 1.47). Mean (SD) VAS scores for acceptability of taste ranged from 54.4 (25.0) (preparation E) to 74.4 (20.1) (preparation C) (P = 0.03 preparation E vs all other preparations). The only significant difference in taste criteria was in acidity, with preparation A being the least acidic according to patients' ratings on the VAS (1.4 [0.7] vs 1.8 [0.4] [mean of the other 5 preparations combined]; P = 0.04 preparation A vs all other preparations). Mild dehydration occurred in 6 subjects (1 for each preparation). No clinical or biological adverse effects were found.

CONCLUSIONS

In this study of 6 colonic cleansing preparations in healthy volunteers, the use of high-dose vitamin C as an osmotic agent in addition to PEG did not significantly increase stool output. All 6 preparations were well tolerated.

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.

2 L PEG plus ascorbic acid versus 4 L PEG plus simethicon for colonoscopy preparation: a randomized single-blind clinical trial

BACKGROUND

The 2 L polyethylene glycol (PEG) lavage solution has been proved to be similarly safe and effective as 4 L PEG formulations, in spite of the reduced volume.

OBJECTIVE

To compare low-volume PEG-based solution combined with ascorbic acid with high-volume PEG-based solution combined with simethicon in terms of efficacy and patient tolerability.

METHODS

This was a single-blind prospective randomized trial. Patients were randomized to receive either 2 L PEG plus ascorbic acid (PEG+Asc) or 4 L PEG plus simethicon (PEG+Sim). The primary endpoint was overall colon cleansing evaluation, assessed by blinded investigators using Aronchick score. Secondary end points included patient compliance and tolerability and adverse events.

RESULTS

Sixty patients received PEG+Asc and 60 received PEG+Sim. Overall bowel cleansing score was considered adequate in 81.67% of the PEG+Asc and 80% of the PEG+Sim groups, respectively. Excellent and good ratings were recorded in 11.6% and 38.3% receiving PEG+Asc as compared with 26.6% and 23.3% of patients receiving PEG+Sim. Patient tolerability and safety were similar with both the preparations.

CONCLUSIONS

According to our data, low-volume PEG+Asc has comparable efficacy, safety, and tolerability as high-volume PEG+Sim; therefore, it can be considered as a good alternative solution for bowel preparation. More improvements are necessary to achieve the target of a perfect preparation.

Sugar-free menthol candy drops improve the palatability and bowel cleansing effect of polyethylene glycol electrolyte solution

BACKGROUND

Colon preparations are generally poorly tolerated.

OBJECTIVE

To study the efficacy of sugar-free candy drops in improving palatability and tolerability of polyethylene glycol electrolyte solution (PEG-E).

DESIGN

Single-blind, randomized, controlled trial.

SETTING

University medical center.

PATIENTS

Ambulatory patients scheduled for elective colonoscopy.

INTERVENTION

Menthol candy drops. Patients were randomly assigned to split-dose, 4-L, PEG-E ± cough drops. Palatability was assessed on a linear scale of 1 to 5 (1 = disgusting; 5 = tasty). Quality of preparation, remaining unconsumed volume, and side effects were secondary outcomes.

MAIN OUTCOME MEASUREMENTS

Palatability and tolerability of PEG-E.

RESULTS

A total of 99 patients were enrolled (50 control group, 49 candy drops-added group). The mean (± standard deviation) palatability score was significantly better in candy drop users versus controls (3.9 ± 0.7 vs 2.8 ± 1.2, respectively; P < .001) as were the preparations scored as excellent (63.3% vs 34% of controls; P = .004). Side effects were similar except for nausea (24.5% candy drops vs 44% controls; P = .04). The amount of unconsumed PEG-E was not different between candy drop and control groups (128 [± 361 mL] versus 69 [± 194 mL], respectively; P = .32) but was significantly lower in excellent grade preparations versus other grades (31 [± 103 mL] versus 162 [± 384 mL], respectively; P = .024). On multivariate logistic regression, an excellent preparation was associated with candy drops (odds ratio [OR] 3.3, 95% confidence interval [CI], 1.4-7.8; P = .006) and smaller unconsumed volume of same-day PEG-E [OR 0.996, 95% CI, 0.992-1.000; P = .044).

LIMITATIONS

Single-center study.

CONCLUSION

Sugar-free menthol candy drops are a safe and effective addition to split-dose PEG-E, resulting in improved tolerability and patient compliance, which appears to translate into improved bowel cleansing. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT01541683.).

Colorectal cancer and the elderly

Colorectal cancer and precancerous adenomas disproportionately affect the elderly, necessitating the need for screening and surveillance in this group. However, screening and surveillance decisions in the elderly can be challenging. Special considerations such as comorbid medical conditions, functional status, and cognitive ability play a role in one's decisions regarding the utility of screening and surveillance as well as the success and safety of various screening modalities. This article explores the evidence for screening and surveillance in the elderly, and addresses key challenges unique to this population.

Efficacy and acceptability of sodium picosulphate/magnesium citrate vs low-volume polyethylene glycol plus ascorbic acid for colon cleansing: a randomized controlled trial

AIM

The study compared the efficacy, safety and tolerability of a low-volume picosulphate/magnesium citrate preparation with that of polyethylene glycol plus ascorbic acid (PEG + ASC) in a randomized clinical trial (RCT).

METHOD

A multicentre randomized, single-blinded study was designed. Adult outpatients undergoing colonoscopy received either picosulphate/magnesium citrate (Group 1) or PEG + ASC (Group 2). Bowel cleansing was assessed using the Boston Bowel Preparation Scale (BBPS) and rated as adequate if ≥ 2 in each segment. Patient acceptance, satisfaction and related symptoms were recorded.

RESULTS

Two-hundred and eighty-five patients were included. Preparation was adequate in 75.7% of patients in Group 1 and in 76.5% of patients in Group 2. The mean BBPS scores for the entire colon and for the right colon were comparable between groups. In addition, 97.1% patients in Group 1 and 84.8% in Group 2 reported no or mild discomfort (P < 0.0003) and 97.8% and 83.4% expressed their willingness to repeat the preparation (P < 0.0001). Palatability was better in Group 1, whereas related symptoms occurred more frequently in Group 2. Regardless of which preparation was used, the split regimen was associated with better cleansing compared with the same-day method (OR = 3.39; 95% CI: 1.1-10.4; P = 0.03). Other predictors of poor cleansing were comorbidity, discomfort during preparation and incomplete (< 75%) preparation.

CONCLUSION

Both picosulphate/magnesium citrate and PEG + ASC are effective for bowel preparation. Tolerability and palatability are better for picosulphate/magnesium citrate. A split schedule is associated with higher cleansing quality also for low-volume regimens.

The modern bowel preparation in colonoscopy

Adequate bowel preparation is essential for optimal colonoscopy. Suboptimal bowel preparation occurs in 25% to 40% of cases and is associated with canceled procedures, prolonged procedure time, incomplete examination, increased cost, and missed pathology. There are several effective formulations for colon cleansing with a good safety profile. Split dosing should be implemented whenever possible in an effort to enhance tolerance and adherence, and improve mucosal visibility and overall quality of the examination. In this review, modern bowel preparations are discussed including their mechanism of action, mode of use, safety, and how to optimize outcomes.

Safety, patient's tolerance, and efficacy of a 2-liter vitamin C-enriched macrogol bowel preparation: a randomized, endoscopist-blinded prospective comparison with a 4-liter macrogol solution

BACKGROUND

Optimal bowel preparation is associated with lower polyp miss rates, but patients have difficulties in complying with the usual 4-L bowel preparation.

OBJECTIVE

This study aimed to compare the safety, acceptance, and efficacy of 2-L polyethylene glycol electrolyte solution enriched in vitamin C with 4-L polyethylene glycol electrolyte solution.

DESIGN

This study is an endoscopist-blinded randomized controlled trial.

SETTINGS

The study was conducted at a tertiary referral hospital.

PATIENTS

Consecutive outpatients were randomly assigned to receive 4-L polyethylene glycol electrolyte solution or 2-L polyethylene glycol electrolyte solution enriched in vitamin C with 2 L of clear fluids in a single-dose or a split-dose regime.

MAIN OUTCOME MEASURES

Safety was assessed by blood sampling before and after the preparation and by a 30-day postcolonoscopy chart and complication database review. Acceptance was investigated by questionnaires, and the adequacy of bowel preparation was assessed by the Aronchick and Ottawa scales.

RESULTS

One hundred eighty-eight patients, 98 in the polyethylene glycol electrolyte solution enriched in vitamin C group and 90 in the polyethylene glycol electrolyte solution group, participated. Although changes in bicarbonate blood concentrations with polyethylene glycol electrolyte solution enriched in vitamin C were seen to such an extent that the blinded investigator correctly guessed the preparation in 75.6%, no unsafe values were observed. A 30-day chart and complication database review revealed 1 severe adverse event of a myocardial infarction in the polyethylene glycol electrolyte solution enriched in vitamin C group. Patient acceptance and compliance were significantly higher with the polyethylene glycol electrolyte solution enriched in vitamin C group. The impact on sleep, daily activities, and physical complaints were similar in both groups. Polyethylene glycol electrolyte solution enriched in vitamin C was noninferior to polyethylene glycol electrolyte solution in cleansing efficacy, but the segmental rating of excellent and good preparation in right and transverse colon was significantly better for polyethylene glycol electrolyte solution, especially when taken as a split dose.

LIMITATIONS

The results cannot be extrapolated to immobile inpatients with comorbidities. Another limitation of our study was the inability to determine plasma vitamin C concentrations and to assess the quality of colonoscopy performance.

CONCLUSIONS

Two-liter polyethylene glycol electrolyte solution enriched in vitamin C is a safe and patient-friendly alternative to the 4-L polyethylene glycol electrolyte solution. Endoscopists slightly preferred the 4-L polyethylene glycol electrolyte solution.

A Comparison of 2 L of Polyethylene Glycol and 45 mL of Sodium Phosphate versus 4 L of Polyethylene Glycol for Bowel Cleansing: A Prospective Randomized Trial

Background/Aims

Polyethylene glycol (PEG)-based gut lavage solutions are safe and effective, but require the intake of large volumes of fluid. The use of 2 L PEG plus 45 mL sodium phosphate (PEG2 plus NaP) was compared with 4 L PEG (PEG4) for bowel cleansing before colonoscopy.

Methods

Patients were randomized to the PEG2 plus NaP group or PEG4 group between January 1, 2009 and March 31, 2010. One hundred and thirty patients were included in the PEG2 plus NaP group, and 141 patients in the PEG4 group.

Results

The qualities of the bowel preparation, based on the Ottawa scale were not significantly different between the groups (4.8±2.25 for the PEG2 plus NaP group vs. 5.11±2.26 for the PEG4). In addition, there were no significant differences in side effects. Laboratory findings after bowel preparation, including electrolyte, phosphorus and creatinine levels, were within the normal ranges in both groups.

Conclusions

PEG2 plus NaP provides good cleansing that is similar to PEG4, but with a lower volume. However, because PEG2 plus NaP can cause serious side effects such as calcium deposition in the kidneys (i.e., nephrocalcinosis), this solution might be considered for the outpatients who cannot tolerate PEG4.

A validated bowel-preparation tolerability questionnaire and assessment of three commonly used bowel-cleansing agents

BACKGROUND AND STUDY AIMS

Bowel-cleansing studies are frequently underpowered, poorly designed, and with subjective assessments. Consensus on tolerability of the bowel-cleansing agents is thus lacking. This study developed and validated a bowel-preparation tolerability questionnaire and used it to assess the tolerability of three bowel-cleansing agents, sodium phosphate (NaP), polyethylene glycol (PEG), and sodium picosulphate (Pico), in a prospective randomized single-blinded trial of ambulatory patients.

PATIENTS AND METHODS

The bowel-preparation tolerability questionnaire was validated in 125 consecutive patients and then bowel-preparation agent tolerability was assessed in 634 patients in a prospective randomized single-blinded trial.

RESULTS

The questionnaire's internal consistency was satisfactory with good to excellent "test-retest" reliability for aggregate tolerability and visual analogue scores. Validity assessment confirmed it as reliable and accurate. Of 634 patients, 97.8 % took >75 % of the allocated preparation and 98.9 % completed the questionnaire. Overall, Pico was better tolerated than PEG (p < 0.001) and NaP (p < 0.001). NaP was better tolerated than PEG (p < 0.001). Regardless of the bowel-preparation agent used, males tolerated them better than females (p = 0.009) as did patients having their procedure in the AM. Older patients, however, tolerated all preparations better than younger patients (p = 0.006).

CONCLUSIONS

This study used the first validated bowel-preparation tolerability questionnaire and identified that age, sex, and procedure time all impacted tolerability. Overall, Pico was best tolerated, but PEG's tolerability in patients ≥60 years was equal to that of Pico and NaP, suggesting that PEG can be recommended for older patients to avoid the electrolyte disturbances associated with the osmotic preparations.

Optimizing working-space in laparoscopy: measuring the effect of mechanical bowel preparation in a porcine model

BACKGROUND

Adequate working space is a prerequisite for safe and efficient minimal access surgery. No objective data exist in literature about the effect of mechanical bowel preparation (MBP) on working space in laparoscopic surgery. We objectively measured this effect with computed tomography in a porcine laparoscopy model.

METHODS

Using standardized anesthesia, twelve 20-kg pigs without MBP and eight 20-kg pigs with MBP were studied with computed tomography at intra-abdominal pressure (IAP) levels of 0, 5, 10, and 15 mmHg. Volumes and dimensions of the pneumoperitoneum were measured on reconstructed CT images and compared between the pigs with and those without MBP.

RESULTS

A reproducible and statistically significant increase of approximately 500 ml in pneumoperitoneum volume was found in the MBP group at all levels of IAP. This represents a 43 % relative increase at a pneumoperitoneum pressure of 5 mmHg, 21 % at IAP 10 mmHg, and 18 % at IAP 15 mmHg. Peak inspiratory pressure was lower at IAP 0 and 5 mmHg in the MBP group. Anteroposterior diameter in the group with MBP was lower at 0 mmHg, but abdominal dimensions were similar in both groups at all other IAPs. This shows that the gain in working space is due to a diminished volume of the intra-abdominal content and not to compression or displacement of the bowel.

CONCLUSIONS

MBP increases working space by reducing bowel content. Especially at low intra-abdominal working pressures, the increase in working space associated with MBP could represent an important benefit in challenging laparoscopic surgery.

Serial monitoring of the physiological effects of the standard Pico-Salax® regimen for colon cleansing in healthy volunteers

BACKGROUND

Sodium picosulfate⁄magnesium oxide⁄citric acid (Pico-Salax, Ferring Inc, Canada) is used widely in Canada and other countries for colon cleansing before colonoscopy. It is a low-volume osmotic⁄stimulant agent with the potential to deplete intravascular volume and alter electrolyte balance, yet there are little data regarding its effects on these clinically important end points.

OBJECTIVE

To serially measure parameters of intravascular volume and electrolyte status in healthy volunteers over a 24 h period using the standard two-sachet dosing.

METHODS

Twenty volunteers were given one sachet of Pico-Salax at time 0 h and another sachet 5 h later, as per usual bowel cleansing protocol. Subjects were continually monitored during the first 12 h of the study with postural vital signs, serum electrolytes and electrocardiograms obtained at intervals throughout this initial period and again at 24 h postingestion.

RESULTS

No adverse events were reported nor were there any signs of intravascular volume depletion observed. There were decreases in potassium and calcium levels from baseline to 12 h, but these appeared minor and were corrected by 24 h. The proportions of patients with hypermagnesmia at 0 h, 5 h, 12 h and 24 h were 5%, 35%, 35% and 20%, respectively (P<0.05). However, the maximal values were only minimally elevated. Mean serum sodium, phosphate and creatinine levels remained within their respective reference ranges. There was a trend toward an increase in maximum corrected QT intervals from time 0 h (418 ms) to 5 h (430 ms) (P=0.06), but no significant change was seen subsequently at 12 h (419 ms). The subjects tolerated the medication well. The mean number of bowel movements per subject was 8.15 (range four to 15). Subjects consumed a mean (± SD) of 3.49±1.53 L of fluids during the observation period.

CONCLUSIONS

The proportion of individuals with hypokalemia, hypocalcemia and hypermagnesemia following two sachets of Pico-Salax is significant, but the magnitude of the changes was not clinically relevant in this relatively small group, and both calcium and potassium levels normalized at 24 h. Nonetheless, this could have implications in patients with pre-existing electrolyte abnormalities and the safety of dosing with more than two sachets.

Provider acceptance, safety, and effectiveness of a computer-based decision tool for colonoscopy preparation

PURPOSE

To assess provider acceptance of recommendations by a decision tool that scans the electronic medical record and determines whether sodium phosphate may be taken. In addition, to determine decision tool effects on a composite outcome of colonoscopies canceled, rescheduled, aborted, or repeated sooner than recommended due to preparation (prep) quality; prep quality; colonoscopy duration; and patient satisfaction with and tolerance of the preparation.

METHODS

We used 4 alternating 4-week periods to compare the decision tool with usual care for outpatient colonoscopy. All decision tool decisions were reviewed in real-time by gastroenterology nurses and/or physicians. Patients completed a survey about the prep process. Endoscopists blindly rated prep quality. Colonoscopy duration and findings were recorded.

RESULTS

Of 354 persons in the decision tool group, 4 prep decisions were overridden because of patient preference or prior prep failure, but none for medical reasons. Sodium phosphate was used more frequently in the decision tool group (73% vs. 41%; P < 0.01). There was no difference between the decision tool and usual care groups in the composite outcome (26% vs. 30%, respectively; P = 0.29), acceptable prep quality (62% vs. 56%; P = 0.22), colonoscopy duration (28 vs. 30 min; P = 0.17), patient satisfaction (P = 0.38), or preparation tolerance (P = 0.37).

CONCLUSIONS

An electronic medical record-based decision tool can safely and effectively tailor the prep for colonoscopy and may improve colonoscopy efficiency and patient satisfaction.

LIMITATIONS

This study was performed at a single VA medical center and endoscopy unit, relies on the presence of relevant medical conditions and laboratory data in the electronic medical record, and had a higher than expected use of sodium phosphate during usual care.

Impact of previous gastric or colonic resection on polyethylene glycol bowel preparation for colonoscopy

INTRODUCTION

Adequate bowel preparation is essential for successful completion of colonoscopy. This study examines whether previous bowel resection affects the quality of bowel preparation.

METHODS

This study prospectively included patients who had gastric or colonic resection (bowel resection group, n = 92) and a control group (n = 92). All patients received 4 L polyethylene glycol (PEG) for bowel preparation. Quality of colonic preparation was assessed using the Aronchick scale (excellent, good, fair, or poor) and was categorized as satisfactory (excellent or good) or unsatisfactory (fair or poor). We analyzed whether previous gastric or colonic resection is associated with unsatisfactory preparation.

RESULTS

Bowel preparation quality was significantly different between the resection group (0, 39.1, 43.5, and 17.4%, for excellent, good, fair, and poor) and control group (3.3, 53.3, 38.0, and 5.5% for excellent, good, fair, and poor, P = 0.011). Inadequate bowel preparation was significantly higher in the resection group than in the control group (60.9% vs. 43.5%, P = 0.018). Univariate analysis revealed height, weight, body mass index, and bowel resection to be predictors of unsatisfactory preparation. Multivariate analysis revealed bowel resection [odds ratio (OR) 2.12; 95% confidence interval (CI): 1.16-3.86] and obesity (body mass index ≥ 25 kg/m(2)) (OR 2.16; 95% CI: 1.13-4.12) to be independent predictors of unsatisfactory preparation. The prevalence of unsatisfactory and poor bowel preparation quality was 79.3 and 37.9% in obese patients with previous bowel resection.

CONCLUSIONS

Previous bowel resection was an independent predictor of unsatisfactory PEG bowel preparation. More attention is needed for patients with previous bowel resection, especially for obese patients.

Low-volume plus ascorbic acid vs high-volume plus simethicone bowel preparation before colonoscopy

AIM: To investigate the effectiveness of low-volume plus ascorbic acid [polyethylene glycol plus ascorbic acid (PEG + Asc)] and high-volume plus simethicone [polyethylene glycol plus simethicone (PEG + Sim)] bowel preparations.

METHODS: A total of one hundred and forty-four outpatients (76 males), aged from 20 to 84 years (median age 59.5 years), who attended our Department, were divided into two groups, age and sex matched, and underwent colonoscopy. Two questionnaires, one for patients reporting acceptability and the other for endoscopists evaluating bowel cleansing effectiveness according to validated scales, were completed. Indications, timing of examination and endoscopical findings were recorded. Biopsy forceps were used as a measuring tool in order to determine polyp endoscopic size estimation. Difficulty in completing the preparation was rated in a 5-point Likert scale (1 = easy to 5 = unable). Adverse experiences (fullness, cramps, nausea, vomiting, abdominal pain, headache and insomnia), number of evacuations and types of activities performed during preparation (walking or resting in bed) were also investigated.

RESULTS: Seventy-two patients were selected for each group. The two groups were age and sex matched as well as being comparable in terms of medical history and drug therapies taken. Fourteen patients dropped out from the trial because they did not complete the preparation procedure. Ratings of global bowel cleansing examinations were considered to be adequate in 91% of PEG + Asc and 88% of PEG + Sim patients. Residual Stool Score indicated similar levels of amount and consistency of residual stool; there was a significant difference in the percentage of bowel wall visualization in favour of PEG + Sim patients. In the PEG + Sim group, 12 adenomas ≤ 10 mm diameter (5/left colon + 7/right colon) vs 9 (8/left colon + 1/right colon) in the PEG + Asc group were diagnosed. Visualization of small lesions seems to be one of the primary advantages of the PEG + Sim preparation.

CONCLUSION: PEG + Asc is a good alternative solution as a bowel preparation but more improvements are necessary in order to achieve the target of a perfect preparation.

[Bowel preparation before colonoscopy]

Colonoscopy is a routinely performed procedure in adults. Completion of the procedure and proper visualization of the intestinal mucosa are highly dependent on the quality of the bowel preparation. The ideal bowel preparation should be safe, well-tolerated and effective. No bowel preparation method meets the ideal criteria for bowel-cleansing prior to colonoscopy. However, polyethylene glycol-electrolyte lavage solution and sodium phosphate are the most commonly used bowel preparations before colonoscopy and colon surgery. NaP preparations appear more effective and better tolerated than standard PEG solutions but should be administered with caution in patients with preexisting or at an increased risk for electrolyte disturbances. Timing and dose are important considerations regardless of the method used. The last generation of preparations improves safety and acceptability by reducing volume of liquid ingested.

Bowel Preparation for Colonoscopy with Sodium Phosphate Solution versus Polyethylene Glycol-Based Lavage: A Multicenter Trial

BACKGROUND

Adequate bowel preparation is essential for accurate colonoscopy. Both oral sodium phosphate (NaP) and polyethylene glycol-based lavage (PEG-ELS) are used predominantly as bowel cleansing modalities. NaP has gained popularity due to low drinking volume and lower costs. The purpose of this randomized multicenter observer blinded study was to compare three groups of cleansing (NaP, NaP + sennosides, PEG-ELS + sennosides) in reference to tolerability, acceptance, and cleanliness.

PATIENT AND METHODS

355 outpatients between 18 and 75 years were randomized into three groups (A, B, C) receiving NaP = A, NaP, and sennosides = B or PEG-ELS and sennosides = C. Gastroenterologists performing colonoscopies were blinded to the type of preparation. All patients documented tolerance and adverse events. Vital signs, premedication, completeness, discomfort, and complications were recorded. A quality score (0-4) of cleanliness was generated.

RESULTS

The three groups were similar with regard to age, sex, BMI, indication for colonoscopy, and comorbidity. Drinking volumes (L) (A = 4.33 + 1.2, B = 4.56 + 1.18, C = 4.93 + 1.71) were in favor of NaP (P = .005). Discomfort from ingested fluid was recorded in A = 39.8% (versus C: P = .015), B = 46.6% (versus C: P = .147), and C = 54.6%. Differences in tolerability and acceptance between the three groups were statistically not significant. No differences in adverse events and the cleanliness effects occurred in the three groups (P = .113). The cleanliness quality scores 0-2 were calculated in A: 77.7%, B: 86.7%, and C: 85.2%.

CONCLUSIONS

These data fail to demonstrate significant differences in tolerability, acceptance, and preparation quality between the three types of bowel preparation for colonoscopy. Cleansing with NaP was not superior to PEG-ELS.

Colorectal cancer screening and surveillance in the elderly patient

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths in the United States. Older age is associated with a rise in colorectal cancer and adenomas, necessitating the need for CRC screening in older patients. However, decisions about CRC screening and surveillance in older adults are often difficult and challenging. The decision requires an individualized assessment that incorporates factors unique to performing colonoscopy in older adults in order to weigh the risks and benefits for each patient according to their overall health and preferences. This review addresses the factors unique to colorectal cancer and performing colonoscopy in older adults that are relevant in weighing the risks and benefits of screening and surveillance in this population.

Polyethylene glycol vs. sodium phosphate for bowel preparation: a treatment arm meta-analysis of randomized controlled trials

Background

Results of meta-analyses of randomized trials comparing PEG and NaP are inconsistent and have not included trials comparing either or both preps to less traditional ones.

AIM: To perform a meta-analysis by treatment arm.

Methods

Using MEDLINE and EMBASE, we identified English-language trials published from 1990 to 2008 that included PEG and/or NaP, and aggregated them by treatment arm into: 4 liter (L) PEG; 2 L PEG; split-dose PEG; two 45 ml doses of NaP +/- adjunctive medication; and NaP tablets. We compared prep quality and the proportion completing the prep.

Results

Among 71 trials (patient N = 10,201), excellent prep quality was present in 34% (CI, 26-41%) for 4 L PEG alone; 39% (CI, 26-51%) for 2 L PEG; 37% (CI, 28-46%) for split-dose PEG; 42% (CI, 33-51%) for NaP solution; 44% (CI, 38-51%) for NaP with adjunctive meds; and 58% (CI, 49-67%) for NaP tablets. Patients receiving NaP were more likely to complete the prep (97% [CI, 96-98%] vs. 90% [CI, 87-92%] for 4L PEG alone); however, completion rates for 2L PEG (98%) and split dose PEG (95%) were similar to NaP.

Conclusions

NaP tablets resulted in better prep quality and higher completion rates compared to other regimens. In comparisons limited by sample size, split dose PEG was not statistically different from NaP solution for completion rate or prep quality.

An endoscopist-blinded, randomized, controlled trial of a simple visual aid to improve bowel preparation for screening colonoscopy

BACKGROUND

The effect of patient education on bowel preparation for colonoscopy has not been well studied. An improvement in patient understanding of the rationale for bowel preparation before colonoscopy might enhance adherence to the prescribed bowel regimen and improve bowel preparation quality.

OBJECTIVE

To measure the effect of a simple educational intervention on the quality of bowel preparation during colonoscopy.

DESIGN

Prospective, single-center, endoscopist-blinded, randomized, controlled trial.

SETTING

Tertiary-care center.

PATIENTS

This study involved outpatients directly referred for screening colonoscopy.

INTERVENTION

Inclusion of a visual aid depicting both clean and dirty colons in addition to standard written colonoscopy instructions.

MAIN OUTCOME MEASUREMENTS

The primary outcome was the quality of the bowel preparation according to the Boston Bowel Preparation Scale (BBPS). Secondary outcomes included the need for repeat colonoscopy because of inadequate bowel preparation, insertion and withdrawal time, polyps detected, and patient tolerance of bowel preparation and colonoscopy.

RESULTS

We analyzed 492 patients given a visual aid and 477 controls. The percentage of colonoscopies with a BBPS score≥5 was similar in both groups (91% visual aid vs 89% control, P=.43). The odds ratio for having a BBPS≥5 in the visual aid group was 1.24 (95% CI, 0.83-1.87) compared with controls. Other secondary outcomes were similar between groups.

LIMITATIONS

Single-center study.

CONCLUSION

A simple card with photographs and text explaining the rationale for bowel preparation did not change the quality of bowel preparation in patients directly referred for screening colonoscopy. Future educational studies may need to include more interactive or intensive methods. (

CLINICAL TRIAL REGISTRATION NUMBER

NCT00643682.).

The timing of bowel preparation is more important than the timing of colonoscopy in determining the quality of bowel cleansing

AIMS

We aimed to compare the quality of bowel preparation and cecal intubation rates between morning and afternoon colonoscopies and to evaluate the difference in quality of bowel preparation according to the intervals between starting and ending intake of bowel preparation agent and the initiation of colonoscopy.

METHODS

In this prospective study, 300 outpatients were instructed to drink PEG solution starting either at 5:00 a.m. (morning group) or at 8:00 a.m. (afternoon group) on the same day. The time when PEG intake was started and completed, and when colonoscopy was begun were recorded. The quality of bowel preparation was assessed using the Ottawa bowel preparation scale.

RESULTS

There was no significant difference in the Ottawa scale between the morning and the afternoon groups (p = 0.14). Patients with intervals of 7 h or less between the initiation of PEG intake and the start of colonoscopy had a better quality of bowel preparation than those with intervals of more than 7 h (p = 0.03). In addition, patients with intervals of 4 h or less between the end of PEG intake and the start of colonoscopy had a better quality of bowel preparation than those with intervals of more than 4 h (p = 0.02).

CONCLUSIONS

The time of day at which colonoscopy is performed, whether during the morning or the afternoon, does not have a significant impact on the quality of bowel preparation. The quality of bowel preparation is significantly better in patients with a shorter time between bowel preparation and the start of colonoscopy.

Magnesium citrate with a single dose of sodium phosphate for colonoscopy bowel preparation

AIM: To evaluate the efficacy and acceptability of magnesium citrate and a single dose of oral sodium phosphate (45 mL) solution for morning colonoscopy bowel preparation.

METHODS: A total of 159 patients were randomly assigned to receive two split doses of 90 mg of sodium phosphate (Group I, n = 79) or magnesium citrate (250 mL, the day before the procedure) followed by 45 mL of sodium phosphate (the day of procedure, Group II, n = 80). The quality of bowel cleansing and the acceptability of each regimen were compared, including the satisfaction, taste, willing to repeat and adverse effects of each regimen.

RESULTS: The quality of bowel cleansing of Group II was as good as that of Group I (An Aronchick scale score of good or excellent: 70.9% vs 81.0%, respectively, P = 0.34; the Ottawa system score: 4.4 ± 2.6 vs 3.8 ± 3.0, respectively, P = 0.76). There was no statistically significant difference between both groups with regard to acceptability, including the satisfaction, taste and willingness to repeat the regimen. A significantly greater number of older patients (over 65 years old) in Group II graded the overall satisfaction as satisfactory (48.1% vs 78.1%, respectively; Group I vs Group II, P = 0.01). There were no significant adverse reactions.

CONCLUSION: Magnesium citrate and a single dose of sodium phosphate was as effective and tolerable as the conventional sodium phosphate regimen and is a satisfactory option.