Effect of supplemental simethicone for bowel preparation on adenoma detection during colonoscopy: A meta-analysis of randomized controlled trials

The Effect of Oral Simethicone in a Bowel Preparation in a Colorectal Cancer Screening Colonoscopy Setting: A Randomized Controlled Trial

Introduction

Current guidelines suggest adding oral simethicone to bowel preparation for colonoscopy. However, its effect on key quality indicators for screening colonoscopy remains unclear. The primary aim was to assess the rate of adequate bowel preparation in split-dose high-volume polyethylene glycol (PEG), with or without simethicone.

Methods

This is an endoscopist-blinded, randomized controlled trial, including patients scheduled for colonoscopy after a positive faecal immunochemical test. Patients were randomly assigned to 4 L of PEG split dose (PEG) or 4 L of PEG split dose plus 500 mg oral simethicone (PEG + simethicone). The Boston Bowel Preparation Scale (BBPS) score, the preparation quality regarding bubbles using the Colon Endoscopic Bubble Scale (CEBuS), ADR, CIR, and the intraprocedural use of simethicone were recorded.

Results

We included 191 and 197 patients in the PEG + simethicone group and the PEG group, respectively. When comparing the PEG + simethicone group versus the PEG group, no significant differences in adequate bowel preparation rates (97% vs. 93%; p = 0.11) were found. However, the bubble scale score was significantly lower in the PEG + simethicone group (0 [0] versus 2 [5], p < 0.01), as well as intraprocedural use of simethicone (7% vs. 37%; p < 0.01). ADR (62% vs. 61%; p = 0.86) and CIR (98% vs. 96%, p = 0.14) did not differ between both groups.

Conclusion

Adding oral simethicone to a split-bowel preparation resulted in a lower incidence of bubbles and a lower intraprocedural use of simethicone but no further improvement on the preparation quality or ADR.

Efficacy and safety of oral sodium sulfate tablet compared with 1-L polyethylene glycol plus ascorbate: a prospective, randomized, endoscopist-blinded trial

BACKGROUND AND AIM

Low-volume bowel preparation solutions, including 1-L polyethylene glycol plus ascorbate (PEG-A), have been developed to improve tolerability. The oral sodium sulfate tablet (OST) is a new agent with simethicone as a preloaded component. We investigated the efficacy, safety, and tolerability of OST compared to 1-L PEG-A.

METHODS

A single-center, prospective, controlled study was performed with randomization into the OST (group A) and 1-L PEG-A (group B) groups. Bowel preparation efficacy was assessed on the Boston Bowel Preparation Scale (BBPS) and Bubble Scale. Safety and tolerability were evaluated using a questionnaire and laboratory examination.

RESULTS

Final analysis was performed on 171 patients (group A: 87, group B: 84). The proportion of bowel preparation success (BBPS ≥ 2 for each colonic segment) in group A was not inferior compared to group B (95.4% vs 96.4%, P = 0.736, 1-sided 97.5% lower confidence limit -7.0%). The adenoma detection rate was not different (59.6% vs 41.9%; P = 0.087). The bubble scale was better in group A (0.2 ± 0.9 vs 1.9 ± 1.7, P < 0.001). All adverse events were mild in both groups. Nausea was less frequent in group A (14.9% vs 38.1%, P = 0.001). Overall satisfaction was better in group A (8.1 ± 2.1 vs 6.4 ± 2.8, P < 0.001). No clinically significant laboratory abnormality developed in both groups. These findings were similarly shown in old patients ≥65 years.

CONCLUSIONS

Both OST and 1-L PEG-A were efficacious, safe, and tolerable for bowel preparation of colonoscopy. The OST showed fewer bubbles and slightly better tolerability.

Minimizing the Risks of Simethicone in Endoscope Reprocessing

This statement was written under the auspices of the World Gastroenterology Organization's Guidelines Committee. The authors are members of the Review Team of the WGO Endoscope Disinfection Guideline and have experience in endoscopy, endoscope reprocessing, and microbiology, including biofilms. During the preparation of the WGO Update on Endoscope Disinfection Guidelines, concerns about simethicone on endoscope channel surfaces compromising cleaning and disinfection were raised. Publications on simethicone, including modes of delivery, effectiveness, and risks, have been reviewed. The paper was written as a companion to the new guidelines with a focus on minimizing the risks of simethicone in endoscope reprocessing.

Prepackaged formula low-residue diet vs. self-prepared low-residue diet before colonoscopy: A multicenter randomized controlled trial

Background and aims

Compared with self-prepared LRD, a prepackaged low-residue diet (LRD) can improve patient compliance, but whether it can further improve the quality of bowel preparation is uncertain. The study aimed to compare the application of the prepackaged formula LRD with self-prepared LRD in bowel preparation for colonoscopy.

Methods

A multicenter randomized controlled trial was conducted in 15 centers. The eligible subjects were randomly assigned to one of two groups: the formula LRD group and the self-prepared LRD group. On the day before the colonoscopy, subjects in the self-prepared LRD group were instructed to consume a restricted LRD prepared by themselves, while subjects in the formula LRD group were given six bags of prepackaged formula LRD and instructed to consume them according to their individual need. The primary outcome was an adequate bowel preparation rate. Secondary outcomes mainly included Boston Bowel Preparation Scale (BBPS) scores, dietary restriction compliance rate, tolerance, satisfaction, adenoma detection rate (ADR), and adverse reactions. The trial was registered at ClinicalTrials.gov under the identifier NCT03943758.

Results

A total of 550 subjects were recruited. Compared with the self-prepared LRD group, the formula LRD group showed a higher adequate bowel preparation rate (94.5 vs. 80.4%; P < 0.01), BBPS scores (7.87 ± 1.13 vs. 6.75 ± 1.47; P < 0.01), dietary compliance rate (92.4 vs. 78.9%; P < 0.01), tolerance (P < 0.01 in degree of hunger, intensity of physical strength, and negative influence on daily activities), satisfaction (8.56 ± 1.61 vs. 7.20 ± 2.02; P < 0.01), and ADR (25.6 vs. 16.0%; P < 0.01). There was no significant difference in adverse reactions.

Conclusion

Compared with self-prepared LRD, the formula LRD showed similar safety and higher bowel preparation quality, compliance, and tolerance in bowel preparation. More formula LRDs could be designed according to different dietary habits and ethnic populations, and further researches are warranted to confirm their effect.

Clinical trial registration

https://register.clinicaltrials.gov, identifier: NCT03943758.

Oral sulfate solution benefits polyp and adenoma detection during colonoscopy: Meta-analysis of randomized controlled trials

OBJECTIVES

Although oral sulfate solution (OSS) has been revealed to be not only safe and efficacious but also noninferior to polyethylene glycol with ascorbic acid (PEG + ASC), it is unclear whether OSS can ultimately increase the polyp detection rate (PDR) and adenoma detection rate (ADR). We performed this meta-analysis to estimate the effect of OSS on PDR and ADR during colonoscopy.

METHODS

We searched PubMed, EMBASE, and the Cochrane Library to identify relevant randomized controlled trials (RCTs) investigating the comparative effect of OSS versus PEG + ASC on the PDR and ADR during colonoscopy. Cecal intubation time (CIT), cecal intubation rate (CIR), and bowel preparation score were also evaluated. Review Manager (RevMan) version 5.3.0 was used to perform statistical analysis.

RESULTS

Eight RCTs involving 2059 patients fulfilled the selection criteria. Meta-analysis suggested that OSS significantly increased the PDR (47.34% vs. 40.14%, risk ratio [RR] 1.13, 95% confidence interval [CI] 1.03-1.24, P = 0.01) and ADR (44.60% vs. 38.14%, RR 1.17, 95% CI 1.03-1.33, P = 0.01) during colonoscopy. Subgroup analysis showed that the beneficial effects of OSS on PDR and ADR were consistent among patients with mean age >55 years and with body mass index <25 kg/m² receiving outpatient colonoscopy, morning colonoscopy, and the 2-L bowel preparation protocol. Meanwhile, patients receiving OSS had a beneficial bowel preparation score.

CONCLUSION

Compared with polyethylene glycol-based regimens, the OSS bowel preparation regimen significantly increased the PDR and ADR in patients undergoing colonoscopy.

From advanced diagnosis to advanced resection in early neoplastic colorectal lesions: Never-ending and trending topics in the 2020s

Colonoscopy represents the most widespread and effective tool for the prevention and treatment of early stage preneoplastic and neoplastic lesions in the panorama of cancer screening. In the world there are different approaches to the topic of colorectal cancer prevention and screening: different starting ages (45-50 years); different initial screening tools such as fecal occult blood with immunohistochemical or immune-enzymatic tests; recto-sigmoidoscopy; and colonoscopy. The key aspects of this scenario are composed of a proper bowel preparation that ensures a valid diagnostic examination, experienced endoscopist in detection of preneoplastic and early neoplastic lesions and open-minded to upcoming artificial intelligence-aided examination, knowledge in the field of resection of these lesions (from cold-snaring, through endoscopic mucosal resection and endoscopic submucosal dissection, up to advanced tools), and management of complications.

Supplementary education can improve the rate of adequate bowel preparation in outpatients: A systematic review and meta-analysis based on randomized controlled trials

Background

Colonoscopy is widely used for the screening, diagnosis and treatment of intestinal diseases. Adequate bowel preparation is a prerequisite for high-quality colonoscopy. However, the rate of adequate bowel preparation in outpatients is low. Several studies on supplementary education methods have been conducted to improve the rate of adequate bowel preparation in outpatients. However, the controversial results presented encourage us to perform this meta-analysis.

Method

According to the PRISMA statement (2020), the meta-analysis was registered on PROSPERO. We searched all studies up to August 28, 2021, in the three major electronic databases of PubMed, Web of Science and Cochrane Library. The primary outcome was adequate bowel preparation rate, and the secondary outcomes included bowel preparation quality score, polyp detection rate, adenoma detection rate, cecal intubation time, withdrawal time, nonattendance rate and willingness to repeat rate. If there was obvious heterogeneity, the funnel plot combined with Egger’s test, meta-regression analysis, sensitivity analysis and subgroup analysis were used to detect the source of heterogeneity. RevMan 5.3 and Stata 17.0 software were used for statistical analysis.

Results

A total of 2061 records were retrieved, and 21 full texts were ultimately included in the analysis. Our meta-analysis shows that supplementary education can increase the rate of adequate bowel preparation for outpatients (79.9% vs 72.9%, RR = 1.14, 95% CI: 1.08–1.20, I² = 87%, p<0.00001). Supplementary education shortened the withdrawal time (MD: -0.80, 95% CI: -1.54 to -0.05, p = 0.04) of outpatients, increased the Boston Bowel Preparation Scale (MD: 0.40, 95% CI: 0.36 to 0.44, p<0.00001), reduced the Ottawa Bowel Preparation Scale (MD: -1.26, 95% CI: -1.66 to -0.86, p<0.00001) and increased the willingness to repeat (91.9% vs 81.4%, RR:1.14, 95% CI: 1.04 to 1.25, p = 0.004).

Conclusion

Supplementary education for outpatients based on the standard of care can significantly improve the quality of bowel preparation.

Effect of oral simethicone on the quality of colonoscopy: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

In this systematic review and meta-analysis, we aimed to investigate the effect of oral simethicone (SIM), an antifoaming agent, on the quality of colonoscopy in terms of bowel preparation quality, adenoma or polyp detection rate (ADR/PDR) and cecal intubation rate (CIR).

METHODS

All randomized controlled trials (RCTs) on the use of SIM during bowel preparation for colonoscopy published up to 17 March 2021 were identified from the PubMed, EMBASE and Cochrane Library databases. Bowel preparation quality, ADR/PDR/CIR, cecal intubation time (CIT), withdrawal time (WT), patients' tolerability, acceptability and volume of foam and bubbles were compared between the SIM and non-SIM groups.

RESULTS

Thirty-eight RCTs with 10 505 patients were included. Oral SIM significantly increased the rate of total Boston bowel preparation scale (BBPS) score ≥6 (risk ratio [RR]  1.13, P < 0.0001), acceptability (RR  1.15, P = 0.01) and the rate of no or minimal foam and bubbles (RR  1.28, P < 0.00001) and decreased abdominal distension (RR  0.64, P < 0.0001). However, it had no significant impact on overall ADR, overall PDR, CIR, CIT or WT. The rate of total BBPS score ≥6 remained significantly higher in the SIM group when a single-dose laxative regimen or a SIM dosage of ≥320 mg was employed; and ADR, PDR and CIR were significantly increased in the SIM group among colonoscopy clinicians who achieved an ADR <31%, PDR <45% and CIR <96%, respectively.

CONCLUSIONS

Oral SIM can improve bowel preparation quality, especially in patients receiving a SIM dosage of ≥320 mg or a single-dose laxative regimen. SIM may be preferred by junior colonoscopy physicians/trainees with a lower ADR/PDR or CIR.

The Effect of Gender-Affirming Medical Care on the Vaginal and Neovaginal Microbiomes of Transgender and Gender-Diverse People

Transgender and gender diverse individuals may seek gender-affirming medical care, such as hormone therapy or surgery, to produce primary and/or secondary sex characteristics that are more congruent with their gender. Gender-affirming medical care for transmasculine individuals can include testosterone therapy, which suppresses circulating estrogen and can lead to changes in the vaginal epithelium that are reminiscent of the post-menopausal period in cisgender females. Among transfeminine individuals, gender-affirming medical care can include vaginoplasty, which is the surgical creation of a vulva and neovaginal canal, commonly using penile and scrotal skin. The effect of gender-affirming medical care on the vagina of transmasculine individuals and on the neovagina of transfeminine individuals is poorly characterized. This review summarizes what is known of the epithelium and local microbiota of the testosterone-exposed vagina and the neovagina. We focus on potential pathogens and determinants of gynecological health and identify key knowledge gaps for future research.

The Colon Endoscopic Bubble Scale (CEBuS): a two-phase evaluation study

BACKGROUND

To date, no scale has been validated to assess bubbles associated with bowel preparation. This study aimed to develop and assess the reliability of a novel scale - the Colon Endoscopic Bubble Scale (CEBuS).

METHODS

This was a multicenter, prospective, observational study with two online evaluation phases of 45 randomly distributed still colonoscopy images (15 per scale grade). Observers assessed images twice, 2 weeks apart, using CEBuS (CEBuS-0 - no or minimal bubbles, covering < 5 % of the surface; CEBuS-1 - bubbles covering 5 %-50 %; CEBuS-2 - bubbles covering > 50 %) and reporting the clinical action (do nothing; wash with water; wash with simethicone).

RESULTS

CEBuS provided high levels of agreement both in evaluation Phase 1 (4 experts) and Phase 2 (6 experts and 13 non-experts), with almost perfect intraobserver reliability: kappa 0.82 (95 % confidence interval 0.75-0.88) and 0.86 (0.85-0.88); interobserver agreement - intraclass correlation coefficient (ICC) 0.83 (0.73-0.89) and 0.90 (0.86-0.94). Previous endoscopic experience had no influence on agreement among experts vs. non-experts: kappa 0.86 (0.80-0.91) vs. 0.87 (0.84-0.89) and ICC 0.91 (0.87-0.94) vs. 0.90 (0.86-0.94), respectively. Interobserver agreement on clinical action was ICC 0.63 (0.43-0.78) in Phase 1 and 0.77 (0.68-0.84) in Phase 2. Absolute agreement on clinical action per scale grade was 85 % (82-88) for CEBuS-0, 21 % (16-26) for CEBuS-1, and 74 % (70-78) for CEBuS-2.

CONCLUSION

CEBuS proved to be a reliable instrument to standardize the evaluation of colonic bubbles during colonoscopy. Assessment in daily practice is warranted.

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.

Effectiveness of oolong tea and simethicone solution for lens cleansing during colonoscopy: A double-blinded randomized study

BACKGROUND AND AIMS

water is an imperfect agent for lens cleansing during endoscopy due to its incompetence to clean hydrophobic dirt, whereas amphiphilic surfactants have the potential to overcome the limitation of water. The trial was aimed to evaluate the cleansing effectiveness of 2 typical surfactants (simethicone solution and oolong tea) for colonoscopic lens.

METHODS

Oolong tea (O-), low concentration simethicone solution (S1-), high concentration simethicone solution (S2-) and distilled water (D-) were used as washing solutions for colonoscopic lens. Study I: The tip of the colonoscope was immersed in lard oil in order to simulate the blur, and photographs were taken toward a standard colonoscopy image in-vitro pre- and post- each cleansing procedure. The blurred areas of each image were quantified and compared. Study II: 395 consecutive patients who were due to colonoscopy examination were enrolled and randomized into O-, S2-, D-group. The volume of washing solution used and cleansing level during the examination procedure, adenoma and polyp detected per colonoscopy, insertion time and withdraw time were analyzed.

RESULTS

Study I: There were no differences in 4 groups for the blurred areas on images before lens cleansing. The blurred areas after lens cleansing were significantly smaller in 3 groups (O- 8.47 ± 20.91 vs S1- 13.06 ± 10.71 vs S2- 6.76 ± 8.49 vs D- 38.24 ± 29.69, P < .05) than water. The decline range of blurred areas after lens cleansing in oolong tea, low concentration simethicone solution, high concentration simethicone solution groups were significantly higher than that in distilled water group (O- 87.35 ± 20.81 vs S1- 78.12 ± 19.24 vs S2- 89.57 ± 8.50 vs D- 53.39 ± 28.45, P < .05). Study II: The volume of washing solution used in S2-group was significantly smaller than that in O-group and D-group. The cleansing level of the colonoscopic lens of O-group was significantly superior than that of S2-group and D-group.

CONCLUSIONS

The in-vitro test showed oolong tea and simethicone solution can effectively cleans the colonoscopic lens. The clinical trial demonstrated that oolong tea instead of water is effective to provide better visualization during colonoscopy.Registration: Chictr.org.cn No: ChiCTR1900025606.

The Efficacy of Simethicone With Polyethylene Glycol for Bowel Preparation: A Systematic Review and Meta-Analysis

BACKGROUND

Simethicone (SIM) is a commonly used antifoaming agent in the clinic. However, it has not been clarified whether SIM can improve the quality of intestinal preparation and the detection rates of adenomas (ADR) and polyps (PDR). This systematic review and meta-analysis were carried out to mainly evaluate the effect of SIM in bowel preparation for colonoscopy.

MATERIALS AND METHODS

An electronic and a manual search of the literature for studies was conducted in PubMed, EMBASE, and Web of Science in all published data before February 1, 2020. The primary outcomes were the quality of bowel preparation and the ADR and PDR. All the data were calculated using a pooled estimate of risk ratio with 95% confidence intervals, and a random-effect model was used for the calculation.

RESULTS

Eighteen randomized controlled trials with 7187 patients were included in this meta-analysis. Polyethylene glycol (PEG) with SIM improved colon cleansing (P<0.00001), PDR (P=0.006) and the detection rate of lesions in the right colon (P<0.00001) when compared with PEG alone. There was no difference in the ADR (P=0.68), withdrawal time (P=0.06), cecal intubation rate (P=0.98), and cecal intubation time (P=0.65) between 2 groups. The rate of abdominal bloating rate was higher in the PEG group, but there was no significant difference in vomiting (P=0.65), and abdominal pain (P=0.25).

CONCLUSIONS

SIM improves the quality of bowel cleanliness and PDR but not ADR. Besides, SIM improves the detection rate of lesions in the right colon and decreased abdominal bloating, but do not affect vomiting and abdominal pain or cramping.

Effect of antifoaming agent on benign colorectal tumors in colonoscopy: A meta-analysis

BACKGROUND

Although several trials have shown that the addition of antifoaming agents to polyethylene glycol (PEG) can improve bowel preparation, whether PEG plus antifoaming agents have a beneficial role in the detection of benign tumors during colonoscopy has yet to be confirmed. Our aim was to clarify whether adding simethicone to PEG solution could improve the detection of benign colorectal tumors.

AIM

To clarify whether adding simethicone to PEG solution could improve the detection of benign colorectal tumors.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched for articles published prior to September 2019. The outcomes included the detection rates of colorectal adenomas and polyps.

RESULT

Twenty studies were eligible. Although there was no difference in the colorectal adenoma detection rate (ADR), a significant effect of simethicone for diminutive adenomas (< 10 mm) was revealed in the group taking simethicone. We also found that simethicone could significantly improve the ADR in the proximal colon but did not affect the colorectal polyp detection rate. Furthermore, the subgroup analyses revealed a beneficial effect of simethicone on the ADR among Asians (P = 0.005) and those with an ADR < 25% (P = 0.003). Moreover, it was a significant finding that the low dose simethicone was as effective as the high dose one with respect to the detection of benign colorectal tumors.

CONCLUSION

In summary, the addition of simethicone to PEG might improve the detection of diminutive adenomas in the right colon by colonoscopy in Asia. Low-dose simethicone was recommended for the detection of benign colorectal tumors. However, large clinical trials are necessary to validate our results and determine the ideal dose of simethicone.

Efficacy of low-dose versus high-dose simethicone with polyethylene glycol for bowel preparation: A prospective randomized controlled trial

BACKGROUND AND AIM

Additional simethicone (SIM) can improve adequate bowel preparation and adenoma detection rate (ADR). However, there is no consensus on the optimal dose of SIM. In this study, we compared the adequate bowel preparation rate with supplementation of split-dose 2 L polyethylene glycol (PEG) with low-dose SIM (200 mg) versus high-dose SIM (1200 mg).

METHODS

This was a prospective, randomized, observer-blinded trial involving consecutive subjects undergoing colonoscopy. The primary outcome was adequate bowel preparation as assessed by Boston Bowel Preparation Scale (BBPS) score.

RESULTS

Four hundred subjects were randomly allocated to low-dose SIM or high-dose SIM group. Baseline characteristics were comparable in the two groups (P > 0.05). No significant between-group differences were observed with respect to total bubble scale (BS) (8.49 ± 1.00 vs 8.39 ± 1.10, P = 0.07), total BBPS score (8.70 ± 0.81 vs 8.29 ± 1.18, P = 0.98), ADR (33.68% vs 31.79%, P = 0.69) or withdrawal time (13 [range, 10-16] min vs 13 [10-15] min, P = 0.96). The intubation time in low-dose SIM group was significantly shorter than that in high-dose SIM group (8 (4-16) min vs 10 [6-17] min, P = 0.04). In addition, BS scores as well as diminutive ADR in right colon were superior in the low-dose SIM group (2.68 ± 0.59 vs 2.52 ± 0.73, P = 0.03 and 54.29% vs 30.30%, P = 0.046, respectively).

CONCLUSION

Addition of low-dose SIM to split-dose 2 L PEG was as effective as addition of high-dose SIM with respect to adequate bowel preparation, ADR and patient tolerance. However, low-dose SIM was superior with respect to intubation time, right colon BS scores, right colon diminutive ADR and cost savings.

Strategies to Improve Inadequate Bowel Preparation for Colonoscopy

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

Optimal Timing of Simethicone Addition for Bowel Preparation Using Polyethylene Glycol Plus Ascorbic Acid

BACKGROUND

Colonic bubbles obscure the colonic mucosa during colonoscopy following bowel preparation with polyethylene glycol plus ascorbic acid (PEG-Asc). Simethicone is used to enhance visualization during colonoscopy. We aimed to determine the optimal timing of simethicone addition to improve bowel preparation using PEG-Asc.

METHODS

This prospective, randomized study enrolled patients undergoing elective colonoscopy from April 2017 to January 2018. They were randomly assigned to one of the following three groups: PEG-Asc only (control) or simethicone addition in the morning on the day of colonoscopy (PEG-S1) or in the evening of the day prior to colonoscopy (PEG-S2). The primary outcome was the quality of colon cleansing, and the secondary outcomes were the adenoma detection rate (ADR), polyp detection rate (PDR), and diminutive (≤ 5 mm) ADR.

RESULTS

In total, 240 patients were randomly allocated to the three groups; six patients were withdrawn. Of the 234 patients evaluated, 78, 79, and 77 were allocated to the control, PEG-S1, and PEG-S2 groups, respectively. The bubble scores of all colonic segments were lowest in the PEG-S2 group. There was no significant difference in ADR or PDR among the three groups. However, the diminutive ADR was significantly higher in the PEG-S2 group compared to the other two groups (control 5.1% vs. PEG-S1 8.9% vs. PEG-S2 20.8%; P = 0.009).

CONCLUSION

Addition of simethicone to PEG-Asc at the optimal time prevents the formation of air bubbles and so improves the quality of bowel preparation, especially enhancing diminutive ADR.

The role of oral simethicone on the adenoma detection rate and other quality indicators of screening colonoscopy: a randomized, controlled, observer-blinded clinical trial

BACKGROUND AND AIMS

Combining simethicone (SIM) with a colon preparation agent has been shown to improve mucosal visibility during screening colonoscopy, but its effect on the adenoma detection rate (ADR) remains unclear. SIM is commonly used through the endoscope to eliminate bubbles during endoscopy. However, this practice recently has been associated with endoscope-transmitted infections. Our aims were to determine the role of SIM added to a polyethylene glycol preparation on the ADR, procedure times, colon preparation, and intraprocedural use of SIM.

METHODS

This was a randomized, controlled, observer-blinded, clinical trial of patients undergoing screening colonoscopy. Patients with a high risk of colorectal cancer were excluded. Patients were randomly assigned to 2 different preparations: polyethylene glycol plus SIM or polyethylene glycol. Two endoscopists blinded to patient preparation regimens scored its quality by using the Boston Bowel Preparation scale (BBPS) and the bubble scale. Interobserver agreement was calculated. The polyp detection rate, ADR, intraprocedural use of SIM, cecal intubation time, and withdrawal time were recorded. For study purposes, cecal intubation time and withdrawal time were combined to determine the effective procedure time.

RESULTS

No significant difference between the polyethylene glycol plus SIM and polyethylene glycol arms was seen regarding the ADR (33.3% vs 38.8%; P = .881) and effective procedure time (759.3 ± 253.1 seconds vs 800.2 ± 459.6 seconds; P = .373), respectively. Intraprocedural use of SIM as well as the bubble scale score were significantly lower in the polyethylene glycol plus SIM arm (1.6% vs 48.9%; P ≤ .05) and (0.1 vs 2.1; P ≤ .05), respectively. Conversely, no difference was found in the BBPS scores. The interobserver agreement for both scores was strong (bubble scale score kappa = .537; P < .05; BBPS score kappa = .184; P <.05).

CONCLUSION

Adding SIM to a polyethylene glycol preparation did not improve the ADR or effective procedure time. Nevertheless, it resulted in lower bubble scale scores, and more importantly, in less intraprocedural use of SIM. This simple and inexpensive intervention may have the potential to reduce the risk of endoscope-transmitted infections. (Clinical trial registration number: NCT03119168.).

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

BACKGROUND

The 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.

AIM

To evaluate the effect of oral simethicone addition to bowel preparation on intraluminal bubbles reduction during colonoscopy.

METHODS

Described 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.

RESULTS

Higher 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).

CONCLUSION

The 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.

Higher dose of simethicone decreases colonic bubbles and increases prep tolerance and quality of bowel prep: Meta-analysis of randomized controlled trials

BACKGROUND

Antifoaming agents, such as simethicone, may facilitate mucosal inspection during colonoscopy. However, conflicting results have been reported with regard to the impact of simethicone on quality of bowel preparation and adenoma detection rate (ADR).

AIM

To perform a meta-analysis of trials that have compared simethicone vs placebo during colonoscopy.

METHODS

A reproducible literature search of multiple medical databases yielded eleven studies (n = 2605) for inclusion. Studies were compared for quality of bowel preparation, bubbles quality, ADR, and tolerability. Two reviewers independently scored the identified studies for methodology and abstracted pertinent data. Pooling was conducted by both fixed-effects and random-effects models. Relative risk (RR) estimates with a 95% confidence interval (CI) were calculated. Heterogeneity was assessed by I-squared index (I²) statistics.

RESULTS

Patients’ demographic characteristics were comparable in all studies. Of the 2605 patients, 1300 were in the simethicone group, whereas 1305 were in the placebo group. Inadequate bowel preparation was much lower in the simethicone group than in the placebo group [13% vs 24.6%; RR = 0.51 (0.31-0.82); P < 0.0001]. The placebo group was more likely to have significant colonic bubbles than was the simethicone group [35% vs 8%; RR = 1.49 (1.25-1.76); P = 0.0001]. Use of simethicone resulted in a slight, statistically significant increase in ADR compared with the placebo group [26.6% vs 21.6%, RR = 1.07 (1.01-1.13); P = 0.02]. Higher doses of simethicone (> 478 mg) were more likely to result in significant reduction of inadequate bowel preparation, colonic bubbles, and to improve ADR.

CONCLUSION

Adding simethicone improved the quality of bowel preparation, visualization, tolerability, and, eventually, ADR.