What is the best strategy for successful bowel preparation under special conditions?

Selected comorbidities increases the likelihood of an incomplete colonoscopy during colorectal cancer screening

OBJECTIVE

The risk of incomplete colonoscopy is associated with demographic factors and general comorbidity. However, focus on specific comorbidities is limited. This study aimed to investigate the association between selected comorbidities and incomplete colonoscopy in colorectal cancer (CRC) screening.

METHODS

This register-based study included 71,973 Danish screening participants, undergoing colonoscopy after positive fecal immunochemical test. The selected comorbidities were divided into hematological disease, endocrine disease (nondiabetes), endocrine disease (diabetes related), upper gastrointestinal (GI) disease, lower GI disease, other diseases of digestive system, hepatobiliary and pancreatic (HBP) disease, CRC, intraabdominal cancer (except CRC), and mental disease. Outcomes were incomplete colonoscopy due to poor bowel preparation and other reasons. Multivariate logistic regression models were applied.

RESULTS

Of 5,428 (7.5%) incomplete colonoscopies, 2,625 (3.6%) were due to poor bowel preparation and 2,803 (3.9%) due to other reasons. Individuals with specific comorbidities were compared to those without, exhibiting varying odds ratios (OR) for incomplete colonoscopy. For poor bowel preparation, ORs were 1.20 (95%CI: 1.04;1.39), 1.43 (95%CI: 1.30;1.56), 1.86 (95%CI: 1.66;2.09), 1.27 (95%CI: 1.12;1.43), and 1.64 (95%CI: 1.47;1.83) for hematological, endocrine (nondiabetes), endocrine (diabetes related), HBP, and mental disease, respectively, and 1.29 (95%CI: 1.09;1.52) for intraabdominal cancer (except CRC). Incomplete colonoscopies due to other reasons showed ORs of 1.24 (95%CI: 1.08;1.43), 1.18 (95%CI: 1.03;1.36), 1.19 (95%CI: 1.05;1.35), and 1.30 (95%CI: 1.15;1.47) for hematological, endocrine (diabetes related), HBP, and mental disease, respectively, and 1.35 (95%CI: 1.15;1.60) for intra-abdominal cancer (except CRC).

CONCLUSION

Participants with specific comorbidities had significantly higher probability of having an incomplete colonoscopy, suggesting that certain comorbidities could be used prospectively as a predictive factor.

Bowel preparation with linaclotide and 1 L polyethylene glycol plus ascorbic acid prior to colonoscopy in chronic constipated patients

BACKGROUND AND AIMS

Information on effective bowel preparation (BP) methods for patients with constipation is limited. We recently reported the efficacy of 1 L polyethylene glycol plus ascorbic acid (PEG-Asc) combined with senna for BP; however, this regimen was insufficient in patients with constipation. We hypothesized that the addition of linaclotide, which is approved for the treatment of chronic constipation, to 1 L PEG-Asc would yield results superior to those of senna in patients with constipation.

METHODS

This was a retrospective, single-center study that included outpatients with constipation who underwent BP prior to colonoscopy between March and December 2019 (receiving 1 L PEG-Asc with 24 mg senna) and between January and October 2020 (receiving 1 L PEG-Asc with 500 mg linaclotide).

RESULTS

A total of 543 patients with constipation were included, of whom 269 received linaclotide and 274 received senna. The rate of inadequate BP was significantly lower (11% vs 20%, p < 0.01) and the adenoma detection rate was significantly higher (54% vs 45%, p = 0.04) in the linaclotide group than in the senna group. Multivariate analysis revealed that the linaclotide regimen significantly reduced the risk of inadequate BP (odds ratio = 0.36, 95% confidence interval = 0.21-0.60, p < 0.01).

CONCLUSIONS

The linaclotide regimen significantly increased BP efficacy and the adenoma detection rate compared with the senna regimen without reducing tolerability and is therefore a promising new option for BP in patients with constipation.

Impact of colonoscopy on health-related quality of life: findings from the RECEDE study

BACKGROUND

Colonoscopy is a valuable diagnostic tool but the procedure and the preparation for it cause anxiety and discomfort that impacts on patients' health-related quality of life (HRQoL). The 'disutility' of undergoing an invasive colonoscopy needs to be considered and accounted for in comprehensive cost-utility analyses that compare different diagnostic strategies, yet there is little empirical evidence that can be used in such studies. To fill this gap, we collected and analysed data on the effect of a colonoscopy examination on patients' HRQoL that can be used in economic evaluations.

METHODS

Patients scheduled to undergo a colonoscopy at a large NHS hospital were asked to complete the EuroQol EQ-5D-5 L instrument: (i) before the procedure, at the time of consent (T1), (ii) while undergoing bowel preparation (T2) and (iii) within 24 h after the procedure (T3). Complete responses were translated into preference-based HRQoL (utility) values using a UK-specific value set and were analysed using descriptive and inferential statistical analyses.

RESULTS

Two-hundred and seventy-one patients with gastrointestinal symptoms referred for a colonoscopy provided complete EQ-5D-5 L questionnaires at all three assessment points. At T1, the mean EQ-5D-5 L value was 0.76 (95%CI: 0.734-0.786). This value dropped to 0.727 at T2 (95%CI: 0.7-0.754, before increasing again to 0.794 (95%CI: 0.768-0.819) at T3. Both changes were statistically significant (p-value < 0.001).

CONCLUSIONS

Preference-based HRQoL (utility) values reported by patients undergoing a colonoscopy dropped during bowel preparation and rose again shortly after the colonoscopy. This pattern was largely consistent across patients with different characteristics, symptoms and diagnoses.

Colonoscopy Utilization in Elderly Patients with Dementia: Characteristics, Complications, and Charges in a National Matched-Cohort Analysis

BACKGROUND

It is projected that the elderly population will continue to increase. Many will develop chronic conditions such as dementia.

AIMS

Our aims are to describe the utilization of colonoscopy among patients with dementia and compare outcomes in those with and without dementia.

METHODS

This population-based analysis utilized the National Inpatient Sample (NIS) during 2019. Patients with dementia over the age of 60 years receiving colonoscopy were identified utilizing ICD-10 codes. Logistic regression was used for propensity score matching between the comparison groups. A Greedy one-to-one matching algorithm was utilized along with standardized mean differences to assess balance. Mcnemar test, signed rank sum, and paired t-test were used to compare the outcomes.

RESULTS

Initially, 50,692 patients without dementia were compared with 4323 patients with dementia. Patients with dementia were more likely to be female, older, less likely White, had lower income, and more likely to be on Medicare. In the matched comparison (4176 in each group), complication analysis showed that patients with dementia did not have higher colonoscopy-related complications. They did have higher rates of other complications including renal/AKI (p = 0.0042), pulmonary/pneumonia (p = 0.003), cerebrovascular accidents (p = 0.0063), and sepsis (< 0.0001). Patients with dementia were also less likely to have routine discharges (< 0.0001), had longer hospital stays (< 0.0001), and higher hospital costs (< 0.0001).

CONCLUSIONS

Elderly patients with dementia have similar colonoscopy-related complications as patients without dementia. However, they do have higher complications in general. The decision whether to perform colonoscopy in this patient population is multifactorial. A careful assessment of a dementia patient's history can help with this decision.

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

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

Same-day single-dose vs large-volume split-dose regimens of polyethylene glycol for bowel preparation: A systematic review and meta-analysis

BACKGROUND

Split-dose regimens (SpDs) of 4 L of polyethylene glycol (PEG) have been established as the “gold standard” for bowel preparation; however, its use is limited by the large volumes of fluids required and sleep disturbance associated with night doses. Meanwhile, the same-day single-dose regimens (SSDs) of PEG has been recommended as an alternative; however, its superiority compared to other regimens is a matter of debate.

AIM

To compare the efficacy and tolerability between SSDs and large-volume SpDs PEG for bowel preparation.

METHODS

We searched MEDLINE/PubMed, the Cochrane Library, RCA, EMBASE and Science Citation Index Expanded for randomized trials comparing (2 L/4 L) SSDs to large-volume (4 L/3 L) SpDs PEG-based regimens, regardless of adjuvant laxative use. The pooled analysis of relative risk ratio and mean difference was calculated for bowel cleanliness, sleep disturbance, willingness to repeat the procedure using the same preparation and adverse effects. A random effects model or fixed-effects model was chosen based on heterogeneity analysis among studies.

RESULTS

A total of 18 studies were included. There was no statistically significant difference of adequate bowel preparation (relative risk = 0.97; 95%CI: 0.92-1.02) (14 trials), right colon Boston Bowel Preparation Scale (mean difference = 0.00; 95%CI: -0.04, 0.03) (9 trials) and right colon Ottawa Bowel Preparation Scale (mean difference = 0.04; 95%CI: -0.27, 0.34) (5 trials) between (2 L/4 L) SSDs and large-volume (4 L/3 L) SpDs, regardless of adjuvant laxative use. The pooled analysis favored the use of SSDs with less sleep disturbance (relative risk = 0.52; 95%CI: 0.40, 0.68) and lower incidence of abdominal pain (relative risk = 0.75; 95%CI: 0.62, 0.90). During subgroup analysis, patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation than SpDs (P < 0.05). No significant difference in adverse effects, including nausea, vomiting and bloating, was found between the two arms (P > 0.05).

CONCLUSION

Regardless of adjuvant laxative use, the (2 L/4 L) SSD PEG-based arm was considered equal or better than the large-volume (≥ 3 L) SpDs PEG regimen in terms of bowel cleanliness and tolerability. Patients that received low-volume (2 L) SSDs showed more willingness to repeat the procedure using the same preparation due to the low-volume fluid requirement and less sleep disturbance.

Low-Volume Bowel Preparation Is Associated With Reduced Time to Colonoscopy in Hospitalized Patients: A Propensity-Matched Analysis

INTRODUCTION

Delays in inpatient colonoscopy are commonly caused by inadequate bowel preparation and result in increased hospital length of stay (LOS) and healthcare costs. Low-volume bowel preparation (LV-BP; sodium sulfate, potassium sulfate, and magnesium sulfate ) has been shown to improve outpatient bowel preparation quality compared with standard high-volume bowel preparations (HV-BP; polyethylene glycol ). However, its efficacy in hospitalized patients has not been well-studied. We assessed the impact of LV-BP on time to colonoscopy, hospital LOS, and bowel preparation quality among inpatients.

METHODS

We performed a propensity score-matched analysis of adult inpatients undergoing colonoscopy who received either LV-BP or HV-BP before colonoscopy at a quaternary academic medical center. Multivariate regression models with feature selection were developed to assess the association between LV-BP and study outcomes.

RESULTS

Among 1,807 inpatients included in this study, 293 and 1,514 patients received LV-BP and HV-BP, respectively. Among the propensity score-matched population, LV-BP was associated with a shorter time to colonoscopy (β: -0.43 [95% confidence interval: -0.56 to -0.30]) while having similar odds of adequate preparation (odds ratio: 1.02 [95% confidence interval: 0.71-1.46]; P = 0.92). LV-BP was also significantly associated with decreased hospital LOS among older patients (age ≥ 75 years), patients with chronic kidney disease, and patients who were hospitalized with gastrointestinal bleeding.

DISCUSSION

LV-BP is associated with decreased time to colonoscopy in hospitalized patients. Older inpatients, inpatients with chronic kidney disease, and inpatients with gastrointestinal bleeding may particularly benefit from LV-BP. Prospective studies are needed to further establish the role of LV-BP for inpatient colonoscopies.

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.

Whole-bowel irrigation in cases of poisoning: A retrospective multicentre study of feasibility, tolerability, and effectiveness

BACKGROUND

Whole-bowel irrigation (WBI) is a strategy of gastrointestinal decontamination, recommended by several European and American learned societies, which may be used in the management of the poisoned patients.

OBJECTIVES

The objectives of this study were to describe the feasibility and tolerability of this technique and to compare the clinical outcome of a group of poisoned patients treated with WBI versus that of an untreated group.

METHODS

This was a retrospective and observational study of data recorded by the Angers Poison Control Centre (PCC) between 2012 and 2018. All cases for which the PCC advised WBI were included. The association between outcomes (clinical deterioration after WBI advised by a PCC, length of hospitalisation), WBI treatment, and relevant associated risk factors was determined using univariate and multivariate logistic regression.

RESULTS

A total of 257 patients were included. One hundred forty-one patients were treated with WBI with clearly successful induction of diarrhoea in 47 cases (31%). WBI was not initiated in 89 patients. WBI was initiated but unsuccessful (no diarrhoea) in nine cases. The median age is 46 years (interquartile range: 32-55 years), with a sex ratio (M/F) of 1.3. A total of 27 of 150 patients (18%) who underwent WBI had adverse effects possibly linked to WBI, mainly vomiting (n=23). The patients with clinical deterioration (n=49) were irrigated significantly less often (95% confidence interval: 0.13-0.52; p<0.001). After adjustment for sex, age, time to implementation of WBI, type of substance ingested, and admission to intensive care, patients who were treated with WBI were less likely to deteriorate clinically than patients who were not treated with WBI (p<0.001).

CONCLUSION

Despite a low rate of completion of this procedure, WBI appeared to provide clinical benefits in patients treated in comparison of an untreated group and is associated with an acceptably low risk of direct complications.

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Gastrointestinal endoscopy in children and adults: How do they differ?

Gastrointestinal endoscopy has grown dramatically over the past century, and with subsequent improvements in technology and anaesthesia, it has become a safe and useful tool for evaluation of GI pathology in children. There are substantial differences between paediatric and adult endoscopy beyond size, including: age-related patho-physiology and the different spectrum of diseases in children. Literature on endoscopic procedures in children is sparse but significant. The present review aims at describing the current knowledges on paediatric endoscopy practice and highlights the main areas of differences between paediatric and adult practice.

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

BACKGROUND/AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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

INTRODUCTION

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

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

AIM

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

METHODS

A systematic review of the literature following the PRISMA guidelines was performed using Medline, Scopus, EMBASE, Central, Cinahl and Lilacs. No restrictions were placed for country, year of publication or language. The last search in the literature was performed on November 20^th, 2017. Only randomized clinical trials with full texts published were included. The subjects included were adult outpatients who underwent bowel cleansing for elective colonoscopy. The included studies compared sodium picosulphate with magnesium citrate (SPMC) and PEG for bowel preparation. Exclusion criteria were the inclusion of inpatients or groups with specific conditions, failure to mention patient status (outpatient or inpatient) or dietary restrictions, and permission to have unrestricted diet on the day prior to the exam. Primary outcomes were bowel cleaning success and/or tolerability of colon preparation. Secondary outcomes were adverse events, polyp and adenoma detection rates. Data on intention-to-treat were extracted by two independent authors and risk of bias assessed through the Jadad scale. Funnel plots, Egger’s test, Higgins’ test (I²) and sensitivity analyses were used to assess reporting bias and heterogeneity. The meta-analysis was performed by computing risk difference (RD) using Mantel-Haenszel (MH) method with fixed-effects (FE) and random-effects (RE) models. Review Manager 5 (RevMan 5) version 6.1 (The Cochrane Collaboration) was the software chosen to perform the meta-analysis.

RESULTS

662 records were identified but only 16 trials with 6200 subjects were included for the meta-analysis. High heterogeneity among studies was found and sensitivity analysis was needed and performed to interpret data. In the pooled analysis, SPMC was better for bowel cleaning [MH FE, RD 0.03, IC (0.01, 0.05), P = 0.003, I² = 33%, NNT 34], for tolerability [MH RE, RD 0.08, IC (0.03, 0.13), P = 0.002, I² = 88%, NNT 13] and for adverse events [MH RE, RD 0.13, IC (0.05, 0.22), P = 0.002, I² = 88%, NNT 7]. There was no difference in regard to polyp and adenoma detection rates. Additional analyses were made by subgroups (type of regimen, volume of PEG solution and dietary recommendations). SPMC demonstrated better tolerability levels when compared to PEG in the following subgroups: “day-before preparation” [MH FE, RD 0.17, IC (0.13, 0.21), P < 0.0001, I² = 0%, NNT 6], “preparation in accordance with time interval for colonoscopy” [MH RE, RD 0.08, IC (0.01, 0.15), P = 0.02, I² = 54%, NNT 13], when compared to “high-volume PEG solutions” [MH RE, RD 0.08, IC (0.01, 0.14), I² = 89%, P = 0.02, NNT 13] and in the subgroup “liquid diet on day before” [MH RE, RD 0.14, IC (0.06,0.22), P = 0.0006, I² = 81%, NNT 8]. SPMC was also found to cause fewer adverse events than PEG in the “high-volume PEG solutions” [MH RE, RD -0.18, IC (-0.30, -0.07), P = 0.002, I² = 79%, NNT 6] and PEG in the “low-residue diet” subgroup [MH RE, RD -0.17, IC (-0.27, 0.07), P = 0.0008, I² = 86%, NNT 6].

CONCLUSION

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

Bowel Preparation for a Better Colonoscopy Using Polyethylene Glycol or C-lax: A Double Blind Randomized Clinical Trial

BACKGROUND

Ideal bowel preparation regimen for a suitable colonoscopy should be safe, and well tolerated, and should rapidly clear gastrointestinal tract. Soluble polyethylene glycol (PEG) is the most common cleansing drug and Senna or C-Lax (Cassia angustifolia Vahl) is an alternative herbal one. This study was designed to compare the efficacy of PEG and C-lax in bowel preparation.

METHODS

In this randomized double blind trial (registry number in IRCT.ir: IRCT201601161264N7), 320 patients were randomly assigned in PEG or C-lax groups. PEG solution was prepared from 5×70 gr sachets in 20×250cc water (250 ml every 15 minutes), prescribed 24h before the colonoscopy. In the other group 3×60 ml C-lax syrup glasses (each containing 90 mg senozid B) was given in two divided doses (1.5 glasses of 250cc every 12 hours), 24h before the colonoscopy. Ottawa score was used to evaluate the quality of bowel preparation. Chi-square test, Student t test, MannWhitney test and multivariate analysis were used to analyze the data.

RESULTS

Of these patients with the mean (SD) age of 50 (15.16) years, 162 (50.8%) were men. Mean (SD) Ottawa score was 2.57 (0.2) and 3.15 (0.31) in the PEG and C-lax group, respectively (p value = 0.81). Multivariate analysis showed that less opium consumption (p < 0.001) and higher educational level (p =0.005) were associated with better bowel preparation.

CONCLUSION

C-Lax is non-inferior to PEG solution in cleansing colon. The quality of bowel preparation was lower in opium consumers and better in those with higher educational level.

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

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

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Polyethylene glycol plus ascorbic acid for bowel preparation in chronic kidney disease

The safety of polyethylene glycol plus ascorbic acid has not been fully investigated in patients with renal insufficiency. High-dose ascorbic acid could induce hyperoxaluria, thereby causing tubule-interstitial nephritis and renal failure. This study aims to evaluate the safety and efficacy of polyethylene glycol plus ascorbic acid in patients with chronic kidney disease.We retrospectively reviewed prospectively collected data on colonoscopy in patients with impaired renal function. Patients were divided into 2 groups: 2 L polyethylene glycol plus ascorbic acid (n = 61) and 4 L polyethylene glycol (n = 80). The safety of the 2 groups was compared by assessing the differences in laboratory findings before and after bowel cleansing.The laboratory findings were not significantly different before and after the administration of 2 L polyethylene glycol plus ascorbic acid or 4 L polyethylene glycol. In both groups, the estimated glomerular filtration rate was not influenced by the administration of the bowel-cleansing agent. Patients' reports on tolerance and acceptability were better in the 2 L polyethylene glycol plus ascorbic acid group than in the 4 L polyethylene glycol group.The 2 L polyethylene glycol plus ascorbic acid solution is a safe choice for bowel preparation before colonoscopy in patients with impaired renal function.

Polyethylene glycols: An effective strategy for limiting liver ischemia reperfusion injury

Liver ischemia-reperfusion injury (IRI) is an inherent feature of liver surgery and liver transplantation in which damage to a hypoxic organ (ischemia) is exacerbated following the return of oxygen delivery (reperfusion). IRI is a major cause of primary non-function after transplantation and may lead to graft rejection, regardless of immunological considerations. The immediate response involves the disruption of cellular mitochondrial oxidative phosphorylation and the accumulation of metabolic intermediates during the ischemic period, and oxidative stress during blood flow restoration. Moreover, a complex cascade of inflammatory mediators is generated during reperfusion, contributing to the extension of the damage and finally to organ failure. A variety of pharmacological interventions (antioxidants, anti-cytokines, etc.) have been proposed to alleviate graft injury but their usefulness is limited by the local and specific action of the drugs and by their potential undesirable toxic effects. Polyethylene glycols (PEGs), which are non-toxic water-soluble compounds approved by the FDA, have been widely used as a vehicle or a base in food, cosmetics and pharmaceuticals, and also as adjuvants for ameliorating drug pharmacokinetics. Some PEGs are also currently used as additives in organ preservation solutions prior to transplantation in order to limit the damage associated with cold ischemia reperfusion. More recently, the administration of PEGs of different molecular weights by intravenous injection has emerged as a new therapeutic tool to protect liver grafts from IRI. In this review, we summarize the current knowledge concerning the use of PEGs as a useful target for limiting liver IRI.

Optimizing bowel preparation for colonoscopy: a guide to enhance quality of visualization

Colonoscopy is an important screening and therapeutic modality for colorectal cancer. Unlike other screening tests, colonoscopy is dependent on pre-procedure bowel preparation. If the bowel preparation is poor, significant pathology may be missed. Many factors are known to improve bowel preparation. This review will highlight those factors that may optimize the bowel preparation, including choice of bowel preparation, grading or scoring of the bowel preparation, special factors that influence preparation, and diet prior to colonoscopy that affects bowel preparation. The aim of the review is to offer suggestions and guide endoscopists on how to optimize the bowel preparation for the patients undergoing colonoscopy.

2-Litre polyethylene glycol-citrate-simethicone plus bisacodyl versus 4-litre polyethylene glycol as preparation for colonoscopy in chronic constipation

BACKGROUND

Chronic constipation is a risk factor of inadequate bowel preparation for colonoscopy; however, no large clinical trials have been performed in this subgroup of patients.

AIMS

To compare bowel cleansing efficacy, tolerability and acceptability of 2-L polyethylene-glycol-citrate-simethicone (PEG-CS) plus 2-day bisacodyl (reinforced regimen) vs. 4-L PEG in patients with chronic constipation undergoing colonoscopy.

METHODS

Randomized, observer-blind, parallel group study. Adult outpatients undergoing colonoscopy were randomly allocated to 2-L PEG-CS/bisacodyl or 4-L PEG, taken as split regimens before colonoscopy. Quality of bowel preparation was assessed by the Ottawa Bowel Cleansing Scale (OBCS). The amount of foam/bubble interfering with colonic visualization was also measured.

RESULTS

400 patients were enrolled. There was no significant difference in successful cleansing (OBCS score ≤6): 80.2% in the 2-L PEG-CS/bisacodyl vs. 81.4% in the 4-L PEG group. Significantly more patients taking 2L PEG-CS/bisacodyl showed no or minimal foam/bubbles in all colonic segments (80% vs. 63%; p<0.001). 2-L PEG-CS/bisacodyl was significantly more acceptable for ease of administration (p<0.001), willingness to repeat (p<0.001) and showed better compliance (p=0.002).

CONCLUSION

Split 2-L PEG-CS plus bisacodyl was not superior to split 4-L PEG for colonoscopy bowel cleansing in patients with chronic constipation; however, it performed better than the standard regimen in terms of colonic mucosa visualization, patient acceptance and compliance.

Prerequisites of colonoscopy

Colonoscopy is a widely accepted method for the evaluation of the colon and terminal ileum. Its diagnostic accuracy and therapeutic safety are influenced by prerequisites, including modulation of medication and bowel cleansing. Appropriate choices of sedative medication and bowel-cleansing regimen, together with diet modification, should be made based on the patient's underlying disease, age, and medication intake. Moreover, effective methods for patient education regarding bowel preparation should be considered.