Volume Of Polyethylene Glycol Research Articles

Effect of carbon quantum dots’ surface functional groups on tribological performance of polyethylene glycol

Nano additives play an important role in improving the lubricating properties and enhancing the bearing capacity of lubricants. However, traditional nano-additives contain harmful elements such as heavy metals, sulfur, phosphorus, which have a non-negligible impact on the green production of modern industry. In this study, four kinds of carbon quantum dots (CQDs) were prepared by hydrothermal synthesis method, namely CQDs, amino modified CQDs (CQDs-NH2), alkyl modified CQDs (CQDs-CH3), and hydroxyl modified CQDs (CQDs-OH). The microscopic morphology, chemical structure and luminescence of CQDs were characterized. The effects of four kinds of CQDs additives on the tribological properties of polyethylene glycol (PEG) were studied. The results showed that compared with PEG, the average friction coefficient and wear volume of PEG containing 3% CQDs-OH decreased by 60.50% and 95.05%, respectively. A composite protective film containing carbon, nitrogen, FeO, Fe2O3 forms on the worn surface, due to the end hydroxyl group of CQDs-OH has good adsorption. In addition, after 3 months of dispersion experiment, the PEG containing 3% CQDs-OH showed the best dispersion stability, and the antifriction effect was still better than that of pure PEG. Therefore, CQDs-OH is a new type of environmentally friendly lubricating additive with great potential.

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

Polyethylene glycol (PEG) solution is widely used as a colonoscopic bowel cleaning agent, although some patients are intolerant due to the need for ingesting large solution volumes and unpleasant taste. A low-volume solution may enhance patient tolerability and compliance in bowel preparation. Accordingly, this study compared the effectiveness of two difference PEG volumes for bowel preparation before colonoscopy in terms of bowel cleanliness, completeness of colonoscopy, patient tolerability and colonoscopy duration. Using a prospective randomised controlled single-blinded study design, 164 patients scheduled for colonoscopy were allocated to two groups (n = 82 patients in each) to receive either the conventional PEG volume (3 L, control group) or the low volume (2 L, intervention group). The Boston Bowel Preparation Scale (BBPS), a validated scale for assessing bowel cleanliness during colonoscopy, was used to score bowel cleanliness in three colon segments. Secondarily, colonoscopy completeness, tolerability to drinking PEG and the duration of colonoscopy were compared between the groups. There were no statistically significant differences between the two intervention groups in terms of bowel cleanliness (P = 0.119), colonoscopy completion (P = 0.535), tolerability (P = 0.190) or the amount of sedation/analgesia required (midazolam, P = 0.162; pethidine, P = 0.708). Only the duration of colonoscopy differed between the two groups (longer duration in the control group, P = 0.039). Low-volume (2 L) PEG is as effective as the standard 3 L solution in bowel cleaning before colonoscopy; however, the superiority of either solution could not be established.

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.

Bowel preparation using 2-L split-dose polyethylene glycol regimen plus lubiprostone versus 4-L split-dose polyethylene glycol regimen: a randomized controlled trial

BackgroundColonoscopy is a standard procedure for evaluating colon diseases and screening for colorectal cancer, and bowel cleanliness prior to colonoscopy is key. The aim of this study was to compare the bowel cleansing efficacy of low-volume (2 L) split-dose polyethylene glycol (PEG) plus single-dose (24 µg) lubiprostone (LB) and high-volume (4 L) split-dose PEG.MethodsPatients scheduled to undergo outpatient colonoscopy between December 2019 and June 2021 at Rajavithi Hospital were enrolled and randomized into two groups: 2 L PEG + LB or 4 L PEG. Colon cleanliness was evaluated using the Boston Bowel Preparation Scale (BBPS) by reviewing images of the colon after completion of colonoscopy. Secondary outcomes comprised cecal intubation rate, procedure time, withdrawal time, polyp detection rate, adenoma detection rate, patient satisfaction, compliance (based on complete ingestion of bowel preparation regimen), willingness to repeat the preparation regimen, and associated adverse events.ResultsOne hundred and forty patients were included, with 70 in each group. The mean total and segment-specific BBPS scores were not significantly different between groups. However, the rate of adequate bowel preparation was significantly higher in the 2 L PEG + LB group than the 4 L PEG group (100% [95% CI 94.6–100] versus 88.4% [95% CI 78.4–94.9], p = 0.004) in the per-protocol analysis. Colonic polyps were the most common finding. The polyp detection rate, adenoma detection rate, and all secondary outcomes were statistically similar in the two groups (p > 0.05).ConclusionsThe combination of 2 L split-dose PEG plus LB improves bowel cleanliness (based on BBPS scores) to a comparable degree to the standard 4 L split-dose PEG, without additional adverse events and with a lower PEG volume.

Low volume polyethylene glycol combined with senna versushigh volume polyethylene glycol, which regimen is better for bowel preparation for colonoscopy? A randomized, controlled, and single-blinded trial.

Background and AimsBowel preparation affects the quality of colonoscopy. Reaching the optimal preparation has been a challenge for years. Polyethylene glycol (PEG) is the sole FDA‐approved substance for this purpose. However, patients find it unpleasant and often complain about its adverse effects. In this study, we aimed to reduce these complaints by lowering the amount of PEG and adding senna which is an herbal stimulant laxative.MethodsFour hundred and eighty‐six patients were admitted for colonoscopy. Finally, 382 patients were enrolled in the study and we divided them into two groups; 186 patients were placed in which conventional high volume PEG‐alone regimen was consumed and 196 patients in which low volume PEG plus senna regimen was offered. The quality of colon preparation was compared between the two groups by independent two samples t‐test (or its corresponding nonparametric test), Fisher's exact, or χ 2 test in SPSS software version 22.ResultsThe colon preparation quality was equally efficient in the two groups as 69.36% in the high volume PEG group and 71.94% in PEG plus senna group had adequate bowel preparation (p = 0.58). Adverse effects, like nausea, bloating, headache, and sleeplessness were significantly less in the low volume PEG plus senna group.ConclusionBesides the fact that bowel preparation by low volume PEG plus senna combination was noninferior to the conventional high volume PEG‐alone regimen, the side effects were much less common with the low volume PEG plus senna regimen.

A retrospective, comparative study between Plenvu and Moviprep as bowel preparation agents for colonoscopy

Optimal bowel preparation is crucial for a successful colonoscopy. Plenvu is a low volume (1 litre) polyethylene glycol (PEG) plus ascorbate-based bowel preparation which has demonstrated a superior cleansing and equal safety and tolerability profile compared with standard agents.[1,2][1] The

Patient-directed versus fixed-volume PEG for colonoscopy preparation: a randomized controlled trial

ABSTRACTBackgroundIndividualization using different volumes of polyethylene glycol is widely regarded as the optimal solution for bowel preparation, while the patient-directed regimen we propose may serve as a reliable individual solution. This study aimed to assess the efficacy, safety, and satisfaction of bowel preparation with a patient-directed regimen.MethodsPatients in the fixed-volume group ingested the same amount of PEG, while those in patient-directed group ingested different amount according to stool consistency or stool water content.ResultsAfter filtering by exclusion criteria, 428 individuals in the fixed-volume group and 103 in the patient-directed group were successfully enrolled and analyzed. Eighty-three (80.6%) individuals in the patient-directed group had a reduced polyethylene glycol volume. There was no significant difference in the bowel preparation efficacy between the two groups (90.0% vs. 90.3%, χ² = 0.01; p = 0.918). Patients in the patient-directed group complained of fewer adverse effects (53.0% vs. 36.9%, χ² = 8.655; p = 0.003), especially vomiting (13.6% vs. 1.0%, χ² = 13.304; p < 0.001). Regarding comfort during bowel preparation, the degree of comfort was not significantly different between groups. Furthermore, the willingness rate for further colonoscopy in the patient-directed group was significantly higher than that in the fixed-volume group (90.3% vs. 77.1%, χ² = 8.912; p < 0.05). Multivariable logistic regression analysis showed that the body mass index served as an independent factor impacting quality of bowel preparation with the patient-directed regimen (OR 1.16, 95% CI 1.00–1.34; p = 0.043).ConclusionsWithout decreasing the bowel preparation efficacy, the patient-directed regimen increased the safety and satisfaction of bowel preparation and is expected to be a regular and individual solution for bowel preparation. Individuals with a lower body mass index are more likely to undertake this new regimen.Trial registration numberChiCTR1900022072 at ChiClinicalTrials.gov

P233 Efficacy and safety of oral sulfate tablet for the bowel preparation in patients with inflammatory bowel disease: multicenter randomized controlled study

Abstract Background Although high and low volume polyethylene glycol(PEG) bowel preparations are recommended for patients with inflammatory bowel disease(IBD) before colonoscopy, sometime it is limited due to poor compliance. So, studies regarding novel low volume preparations in IBD are need, but, there is limited data. We aimed to evaluated the safety, tolerability and efficacy of oral sulfate tablet (OST) by comparison with 2L PEG and ascorbate (PEG/Asc) in patients with IBD. Methods One hundred ten patients with IBD were enrolled in this single-blind, multicenter, non-inferiority study. Patients were assigned either 2L PEG/Asc or OST to be administered in a split-dose regimen. OST patients were administered 14 tablets with more than 1L of free water in the evening, and the following morning. Colonoscopies were performed by blinded investigators. The primary efficacy endpoint was successful bowel cleansing rate, defined as Harefield Cleansing Scale grade A or B as evaluated by blinded endoscopist in each hospital. Secondary endpoints included the presence of residual air bubbles. Adverse events and laboratory evaluations were monitored to assess safety. Flare up of IBD symptoms and mucosa change associated with preparation were also evaluated. Tolerability, in terms of taste and degree of resistance to drink was assessed with VAS score by interview before colnoscopy. Safety was assessed by spontaneously reported adverse events, solicited ratings of expected prep symptoms, and laboratory testing. Results The cleansing score at all the segment was significantly higher in OST group. A high rate of cleansing success was seen with OST (98.1%), which was noninferior to 2L PEG/Asc (98.1%). Proportion of patients with bubble score 0 was significantly higher in OST than 2L PEPG/Asc group (94.5% vs. 50.0%, p&amp;lt;0.001). Satisfaction, in terms of easiness to drink (8.2 ± 1.6 vs. 6.0 ± 2.2, p&amp;lt;0.001) and taste(7.0 ± 2.8 vs. 5.4 ± 2.4, p=0.002) was significantly higher in OST group. More patients in OST group (94.5%) wanted to repeat the same preparation next colonoscopy. There was no significant difference in the development of vomiting and bloating between group. Aphthous ulcers were noted in the same number of patients in both group and symptom flare up were noted in 2 cases of OST group (p=1.000). No clinically significant differences were seen between preps for renal function and serum electrolyte. Conclusion Oral sulfate tablets achieved a high level of cleansing comparable with 2L PEG/Asc in patients with IBD. The risk of mucosal change or symptom relapse were not higher, on the other hand the degree of satisfaction was higher than 2L PEG/Asc. OST split method could be considered as one of the preparation method for patients with inactive IBD.

A Randomized Study Comparison between Split Dosage and Non-Split Dosage PEG-Electrolyte Solution Preparation Methods for Elective Colonoscopy

Background: A two liters low volume polyethylene glycol (PEG) electrolyte solution preparation was proposed for improving patients’ tolerability with either split or non-split dosage cleansing method. Patient compliance, adverse experiences, and cleansing efficacy of each anatomical segment of the colon using both methods should be determined. Objective: To assess the cleansing efficacy of split dosage versus non-split dosage PEG-electrolyte solution for each anatomical segment of the colon according to the inverted Ottawa bowel preparation scale. Materials and Methods: The present study was a prospective, randomized, endoscopist-blinded study. Volunteers that underwent elective screening colonoscopy were eligible for recruitment into the present study. Patients having any contraindication for colonoscopy, or the use of PEG-electrolyte solution such as bowel obstruction, intestinal perforation, or toxic megacolon were excluded. Cleansing efficacy was evaluated by the inverted Ottawa bowel preparation scale for each anatomical segment of the colon. Medical adherence and compliance were evaluated. Participants were asked to rate their satisfaction and inform the presence of any adverse experiences related to the bowel preparation method. Results: Ninety-four volunteers were randomly assigned to two groups. Of these, 46 received the split dosage cleansing method and 48 received the non-split dosages cleansing method. Overall compliance was approximately 94%, comparable for both preparation methods. Average age was 61.5 years for non-split dosage and 60.4 for split dosage group. Satisfaction score in the non-split dosage group was 8.46, which was not significantly different from 8.56 of the split dosage group (p=0.934). Split dosage PEG-electrolyte solution provided comparable degree of cleansing as standard non-split dosages preparation for transverse, descending, sigmoid, and rectum. However, split dosage provided significantly superior cleansing results over the non-split dosages method for ascending colon at good or excellent with 84.7% versus 47.9% (p&lt;0.01), and caecum at good or excellent for 76.1% versus 41.7% (p&lt;0.01) based on the inverted Ottawa bowel preparation scale. Conclusion: Split dosage PEG-electrolyte solution method provided significantly superior cleansing results over the non-split dosages method for right-side colon with comparable satisfaction score and rate of adverse events. Keywords: Bowel preparation; Split dosage cleansing; Quality of bowel preparation

Sodium Picosulphate with Magnesium Citrate versus Polyethylene Glycol for Bowel Preparation in Children: A Systematic Review.

PurposeTo compare the effectiveness, tolerability, acceptability, and safety of sodium picosulphate with magnesium citrate (PS/Mg) and polyethylene glycol (PEG) in children (≤18 years) preparing for colonoscopy.MethodsThree electronic databases (MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials) were searched till July 2020. Only randomized controlled trials (RCTs) were included. At least two authors independently selected studies and performed risk of bias assessment and data extraction.ResultsFour RCTs (n=390), with overall good quality were included. A meta-analysis of two trials (n=224) found no statistically significant difference between the groups with respect to the proportion of patients who had excellent and good scores (≥6 points) according to the Boston Bowel Preparation Scale (relative risk: 0.99; 95% confidence interval [CI]: 0.90 to 1.08). Excellent and good scores were observed in both groups in approximately 90% of children. A meta-analysis of two other trials (n=150) showed no significant difference between the groups with respect to the mean total score for the Ottawa Bowel Preparation Scale (mean difference: 0.20; 95% CI: −0.74 to 1.14). Both regimens provided a comparable safety profile; however, PS/Mg was significantly superior to high volume PEG in terms of tolerability (abdominal pain, nausea, vomiting, bloating/flatulence/fullness) and acceptability (ease of formulation consumption, taste acceptance, need for nasogastric tube, compliance with full dose).ConclusionPS/Mg provides a quality and safety profile similar to PEG for bowel cleansing; however, it has better acceptance and tolerance in children preparing for colonoscopy.

Adherence to the bowel cleansing regimen for pan-enteric capsule endoscopy in patients with suspected Crohn’s disease and factors affecting the image quality

Objective Pan-enteric capsule endoscopy (CE) is an attractive diagnostic approach in patients examined for Crohn’s disease (CD). The aim of this study was to examine the adherence to the recommended bowel cleansing regimen and determine clinical factors affecting the image quality. Methods In a prospective blinded trial, patients with suspected CD were examined with the PillCam Crohn's capsule after bowel preparation with 2 + 2 L of polyethylene glycol (PEG) and sodium phosphate booster. The image quality was graded on a four-point scale. A good or excellent image quality defined a diagnostic procedure. Results Fifty-nine patients participated. The mean volume of PEG was 2.5 L (CI 2.3–2.8). Ten patients (17%) were able to drink all 4 L of PEG, and 44 patients (75%) ingested ≥2 L. The image quality was poor, fair, good or excellent in 0%, 29.3%, 29.3% and 41.4%, respectively. The mean volume of PEG was 1.9 L (CI 1.4–2.4), 2.2 L (CI 1.8–2.7) and 3.2 L (CI 2.8–3.5) in patients with a fair, good or excellent image quality (p < .001). In a regression analysis, only the volume of PEG was associated with the obtained image quality (r s=0.52; p < .001). The diagnostic yield was equal in patients with a diagnostic or non-diagnostic procedure (43.9% and 47.1%, respectively). Conclusions In patients examined with pan-enteric CE for suspected CD, the volume of PEG is the major factor affecting the image quality. Although few patients are able to ingest the recommended volume, the diagnostic yield is not affected.

Efficacy of macrogol 4000 plus electrolytes in bowel preparation for colonoscopy in patients with chronic constipation

BackgroundChronic constipation is a significant factor in poor bowel preparation for colonoscopy. Macrogol 4000 plus electrolytes (Movicol, EA Pharma, Tokyo, Japan), containing polyethylene glycol (PEG) and electrolytes, have been used recently to treat patients with constipation. However, prospective studies on the use of macrogol 4000 for bowel cleansing for colonoscopy are lacking. This study aimed to investigate the efficacy and safety of macrogol 4000 in addition to PEG administered in patients with chronic constipation.MethodsThis single-center, single-arm prospective study enrolled patients with chronic constipation who were scheduled to undergo colonoscopy. The primary endpoint was the proportion of good bowel preparation assessed using the Boston bowel preparation scale (BBPS) (6 or more points). The secondary endpoints were the time from when pPEG (MoviPrep, EA Pharma, Tokyo, Japan) was taken until colonoscopy could be started, amount of PEG taken, number of defecations, whether additional PEG doses were taken, and adverse events. Endoscopy-related endpoints included cecal intubation rate, insertion time, observation time, adenoma detection rate (ADR), and polyp detection rate (PDR). The tolerability of PEG and macrogol 4000 was assessed using a questionnaire.ResultsForty patients were included in the analysis. The median BBPS was 7 (range 3–9) and ≥ 6 points in 37 cases (92.5%). The median time until colonoscopy can be started was 210 min (90–360 min), the median volume of PEG taken was 1500 mL (1000–2000 mL), and the median number of defecations was 7 (3–20). No adverse events were observed. Fourteen patients required an additional dose of PEG. Cecal intubation was achieved in all cases, the median insertion time was 6.0 min (range 2.3–22 min), and the median observation time was 8.8 min (range 4.0–16.0 min). The ADR and PDR were 60.0% and 75.0%, respectively. A proportion of patients rated the tolerability of macrogol 4000 and PEG as 95.0% and 50.0%, respectively.ConclusionsIntake of macrogol 4000 in addition to PEG is effective and safe for colonoscopy in patients with chronic constipation.Clinical trial registration statement This study was registered in the UMIN-CTR database (UMIN-ID000038315).

Influence of PEG on the clustering of active Janus colloids

Micrometer scale “colloidal” particles that propel in a deterministic fashion in response to local environmental cues are useful analogs to self-propelling entities found in nature. Both natural and synthetic active colloidal systems are often near boundaries or are located in crowded environments. Herein, we describe experiments in which we measured the influence of hydrogen peroxide concentration and dispersed polyethylene glycol (PEG) on the clustering behavior of 5 µm catalytic active Janus particles at low concentration. We found the extent to which clustering occurred in ensembles of active Janus particles grew with hydrogen peroxide concentration in the absence of PEG. Once PEG was added, clustering was slightly enhanced at low PEG volume fractions, but was reduced at higher PEG volumes fractions. The region in which clustering was mitigated at higher PEG volume fractions corresponded to the region in which propulsion was previously found to be quenched. Complementary agent based simulations showed that clustering grew with nominal speed. These data support the hypothesis that growth of living crystals is enhanced with increases in propulsion speed, but the addition of PEG will tend to mitigate cluster formation as a consequence of quenched propulsion at these conditions.

Lavage, Simethicone, and Prokinetics—What to Swallow with a Video Capsule

The development of new capsules now allows endoscopic diagnosis in all segments of the gastrointestinal tract and comes with new needs for differentiated preparation regimens. Although the literature is steadily increasing, the results of the conducted trials on preparation are sometimes conflicting. The ingestion of simethicone before gastric and small bowel capsule endoscopy for prevention of air bubbles is established. The value of a lavage before small bowel capsule endoscopy (SBCE) is recommended, although not supported by all studies. Ingestion in the morning before the procedure seems useful for the improvement of mucosa visualization. Lavage after swallowing of the capsule seems to improve image quality, and in some studies also diagnostic yield. Prokinetics has been used with first generation capsules to shorten gastric transit time and increase the rate of complete small bowel visualization. With the massively prolonged battery capacity of the new generation small bowel capsules, prokinetics are only necessary in significantly delayed gastric emptying as documented by a real-time viewer. Lavage is crucial for an effective colon capsule or pan-intestinal capsule endoscopy. Mainly high or low volume polyethylene glycol (PEG) is used. Apart from achieving optimal cleanliness, propulsion of the capsule by ingested boosts is required to obtain a complete passage through the colon within the battery lifetime. Boosts with low volume sodium picosulfate (NaP) or diatrizoate (gastrografin) seem most effective, but potentially have more side effects than PEG. Future research is needed for more patient friendly but effective preparations, especially for colon capsule and pan-intestinal capsule endoscopy.

Life-Inspired Endogenous Dynamic Behavior of Lipid Droplet-like Microcompartments in Artificial Adipocyte-like Structures

Chemical systems that can replicate cellular behaviors are gaining increasing attention and are being used to study various biological processes. Here, a protein- or amylose-based assembly at an oi...

Thermal Property Analysis and Characteristic Study of Ploy Ethylene Glycol with Diverse Molecular Weight for Thermal Energy Storage Material

In this study, the investigation on thermal property and characteristic analysis of Poly Ethylene Glycol (PEGs) material by varying the molecular weights is examined. In this context, the study on thermal energy material storage is explored by using the different techniques such as Differential Scanning Calorimetry (DSC) for persistent heating rate and Thermal Gravity Analysis (TGA) for determining the amount of change of mass of the material in addition to the function of increasing temperature. Subsequently, the characterization of PEGs with different molecular weight is carried out to explore the property and insight of the material by using the Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) by examining the surface topology, crystallography in addition to this the X-Ray Diffraction (XRD) techniques for catch a glimpse of the crystal structure is studied. As an outcome, in the DSC techniques the results made known when the molecular weight increases, correspondingly the melting temperature and solidification temperature similarly increases however, the heat of fusion during the freezing cycle increases. In the TGA techniques, similarly specified increases in the volume of PEG with different molecular weight has resulted in an increase in the temperature. Subsequently, in the characterization of the PEGs, the SEM has shown an enormous amount of insignificant sphere-shaped crystal-like structures which are joined together and impinging on their neighbour’s which paved the way for the formation of a multi-layered lamellar structure in due course activated rise in the solidification temperature in its molecular weight. Henceforth, from the analytical studies, it’s been evident that the molecular weight greatly influences the mechanical and thermal properties of PEGs. In this concern, the PEGs blends are a potential benefit to replace pure components.

Competition between nucleation and confinement in the crystallization of poly(ethylene glycol)/ large aspect ratio hectorite nanocomposites

The overall crystallization kinetics of polymer nanocomposites is determined by nucleation and crystal growth, both of which are greatly affected by confinement. Heterogeneous nucleation is influenced by the interphase area between filler and polymer matrix. Starting with a homogeneous lamellar lyotropic aqueous dispersion of a mixture containing polyethylene glycol (PEG) and varying amounts of a high aspect ratio layered silicate (hectorite, Hec), nanocomposite films were casted containing a systematic variation of the degree of PEG confinement. This is achieved by a partial phase segregation upon drying, where independent of filler content, a thermodynamically stable, 1-dimensional crystalline hybrid with a constant volume of intercalated PEG (0.81 nm corresponding to a fraction of 75 wt% and 55 vol%, respectively) is formed. This intercalated hybrid phase is incorporated into segregated PEG domains. The kinetics of the thermodynamically driven segregation is dependent on the PEG volume available in surplus of the hybrid. Due to the very large lateral extension of the Hec, the segregated domains are increasingly two dimensional. As evidenced by transmission electron micrographs and powder X-ray diffraction, the segregation produces composite structures where, in dependency of filler content, PEG slabs of different thickness are separated by domains of the intercalated hybrid material. The crystallization behavior of these bi-phasic materials was investigated by Differential Scanning Calorimetry (DSC) and Polarized Light Optical Microscopy (PLOM). DSC results reveal a competition between the nucleating effect of Hec, which was particularly important at low amounts, and the confinement of PEG at higher filler loadings. Applying a self-nucleation protocol, the nucleation efficiency of the hectorite was shown to be up to 67%. The isothermal crystallization kinetics accelerated at low Hec contents (nucleation) up to a maximum, and then decreased as Hec content increased (confinement). Additionally, a clear correlation between filler content and the Avrami index was obtained supporting the increase in confinement as filler loading increased.

Effectiveness and tolerability of low volume bowel cleansing polyethylene glycol solution for colonoscopy

A successful colonoscopy depends, among other factors, on a proper colon cleansing. This variable also affects the acceptance of the patient to carry out the study. To analyze the efficacy and tolerability of a low volume polyethylene glycol formulation (2 liters), compared to the conventional presentation of 4 liters. Patients referred for a colonoscopy were randomly divided to receive either two or four liter of polyethylene glycol as bowel cleansing, which was assessed using the Boston score. Raters of the latter were blinded to the volume of polyethylene glycol that the patients used. Seventy-four patients participated in the study. Subjects who received a 4 liters preparation had an average Boston score of 7.78, versus 8.16 for patients who received a volume of 2 liters (p = 0.267). No significant differences in tolerability were observed between both groups. No significant differences in the efficacy and tolerability between a conventional or a reduced volume of polyethylene glycol solution for the preparation of a colonoscopy were observed. These findings may be especially important for subgroups of patients with difficulties for oral administration of fluids.

Randomized, double-blinded, placebo-controlled trial evaluating simethicone pretreatment with bowel preparation during colonoscopy.

BACKGROUNDThe presence of small air bubbles and foam are an impediment to a successful colonoscopy. They impair an endoscopist’s view and diminish the diagnostic accuracy of the study. This has been particularly noted to be of concern with the switch to lower volume polyethylene glycol (PEG) and bisacodyl combination preparation.AIMTo evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy.METHODSDescribed is a prospective, randomized, multi-center, double-blinded, placebo-controlled study to evaluate the use of premixed simethicone formulation with split-regimen, low-volume PEG-bisacodyl combination bowel preparation for 168 outpatients undergoing screening, surveillance, and diagnostic colonoscopies. Primary outcome includes evaluation of bubbles during colonoscopy graded using the Intraluminal Bubbles Scale. Secondary outcomes include evaluation of the Boston Bowel Preparation Scale (BBPS), total number of polyps, polyp size differentiation, polyp laterality, adenoma detection, mass detection, cecal insertion time, withdrawal time, and patient-reported adverse events.RESULTSHigher Intraluminal Bubbles grades III and IV (less than 75% of the mucosa cleared of bubbles/foam requiring intervention with simethicone infused wash) were detected in the placebo group [Simethicone n = 4/84 vs Placebo n = 20/84 (P = 0.007)]. BBPS total score was 7.42 [standard deviation (SD) = ± 1.51] in the simethicone group and 7.28 (SD = ± 1.44) in the placebo group (P = 0.542) from a total of 9. Significantly higher number of adenomas were detected in the simethicone group (P = 0.001).CONCLUSIONThe addition of simethicone to bowel preparation is well advised for its anti-foaming properties. The results of this study suggest that addition of oral simethicone can improve bowel wall visibility.

Mo1628 – Prospective Pre-Colonoscopy Bowel Preparation Study Comparing Novel Capsule Bowel Preparation (CBP) Vs High Volume Polyethylene Glycol Electrolyte Solution Vs Low Volume Polyethylene Glycol Electrolyte Solution

Mo1628 – Prospective Pre-Colonoscopy Bowel Preparation Study Comparing Novel Capsule Bowel Preparation (CBP) Vs High Volume Polyethylene Glycol Electrolyte Solution Vs Low Volume Polyethylene Glycol Electrolyte Solution