The impact of hyoscine-N-butylbromide on adenoma detection during colonoscopy: meta-analysis of randomized, controlled studies

Provider-reported use of butylscopolamine in gastrointestinal endoscopy in Germany

Introduction The anti-cholinergic agent hyoscine-N-butylbromide (HBB) is used in gastrointestinal (GI) endoscopy to decrease motility and facilitate endoscopic procedures. Data from clinical studies to support this practice is limited especially for therapeutic procedures. Likewise, patterns of use among endoscopist are largely unclear. This study sought to assess usage of HBB among German-speaking endoscopists. Material and Methods We conducted an anonymous online survey among endoscopists in German-speaking countries. Results A total of 207 physicians participated in the survey. The majority (76.9%) were experienced endoscopists and 92.3% of respondents use HBB at least occasionally during procedures. The reported median stated frequency of HBB use varied greatly between different types of procedures and increased with the complexity of the procedure being performed. HBB was rarely used in diagnostic esophagogastroduodenoscopies (EGD) (median stated frequency 1% of procedures), while use frequency was significantly higher in EGD with endoscopic mucosal resection (EMR) (10%; p=0.002) and EGD with endoscopic submucosal dissection (ESD) (20%; p<0.001). Similarly, use frequency during diagnostic colonoscopy was lower (5%) compared to colonoscopy with EMR (20%, p=0.005) or ESD (42.5%, p<0.001). The highest use frequency was reported for ERCP (50%). The most frequently stated reason to use HBB was facilitation of the procedure (80.6%) followed by increasing diagnostic yield (58.3%). Conclusion German-speaking endoscopists commonly use HBB, most frequently to facilitate complex therapeutic procedures. Given there is almost no data supporting HBB use in therapeutic endoscopy, we suggest that more research is needed to evaluate benefits and risks of this practice.

Quality in colonoscopy: time to ensure national standards are implemented?

Background

High-quality colonoscopy is crucial to ensure complete mucosal visualisation and to maximise detection of pathology. Previous audits showing variable quality have prompted national and international colonoscopy improvement programmes, including the development of quality assurance standards and key performance indicators (KPIs). The most widely used marker of mucosal visualisation is the adenoma detection rate (ADR), however, histological confirmation is required to calculate this. We explored the relationship between core colonoscopy KPIs.

Methods

Data were collected from colonoscopists in eight hospitals in North East England over a 6-month period, as part of a quality improvement study. Procedural information was collected including number of colonoscopies, caecal intubation rate (CIR), ADR and polyp detection rate (PDR). Associations between KPIs and colonoscopy performance were analysed.

Results

9265 colonoscopies performed by 118 endoscopists were included. Mean ADR and PDR per endoscopist were 16.6% (range 0-36.3, SD 7.4) and 27.2% (range 0-57.5, SD 9.3), respectively. Mean number of colonoscopies conducted in 6 months was 78.5 (range 4-334, SD 61). Mean CIR was 91.2% (range 55.5-100, SD 6.6). Total number of colonoscopies and ADR>15% were significantly associated (p=0.04). Undertaking fewer colonoscopies and using hyoscine butylbromide less frequently was significantly associated with ADR<15%. CIR, endoscopist grade, % male patients, mean patient age and CIR were not significantly related to ADR<15%. In adjusted analyses, factors which affected ADR were PDR and mean patient age.

Conclusion

Colonoscopists who perform fewer than the nationally stipulated minimum of 100 procedures per year had significantly lower ADRs. This study demonstrates that PDR can be used as a marker of ADR; providing age is also considered.

Detection rates of colorectal neoplasia during colonoscopies and their associated factors in the SCREESCO study

BACKGROUND AND AIM

Colonoscopy quality, including lesion detectability, is variable, and factors influencing lesion detection are not fully understood. This study investigated lesion detection rates during colonoscopies and the associated factors in the SCREEning of Swedish COlons (SCREESCO) study.

METHODS

In this cross-sectional analysis of data from SCREESCO, a large-scale randomized controlled trial of colorectal cancer screening in the Swedish population aged 60 years, we assessed data of first-time colonoscopies performed in both colonoscopy and fecal immunochemical test (FIT) arms.

RESULTS

This study included 16 552 individuals. The adenoma detection rate was 23.9% and 37.8% in colonoscopy and FIT arms, respectively. Regarding colonoscopy procedures, a withdrawal time ≥ 6 min was associated with higher detection rates of advanced adenomas (adjusted odds ratio [AOR] 2.474, 95% confidence interval [CI] 1.295-4.723), adenomas (2.181, 1.515-3.140), and proximal serrated lesions (pSLs) (1.713, 1.007-2.915). Antispasmodic use was associated with higher detection rates of these lesions and sessile serrated lesions (SSLs) (AOR, 95% CI: 1.523, 1.295-1.791; 1.361, 1.217-1.522; 1.450, 1.247-1.687; and 1.810, 1.512-2.167, respectively). Insertion time > 20 min was related to lower detection rates of adenomas, pSLs, and SSLs (AOR, 95% CI: 0.753, 0.639-0.887; 0.640, 0.495-0.828; and 0.704, 0.518-0.955, respectively). The relationship between a recent period and higher detection rates of pSLs and SSLs was also demonstrated.

CONCLUSION

Lesion detectability in SCREESCO was mostly acceptable with room for improvement. In addition to sufficient withdrawal time, antispasmodic use and acquiring skills enabling short insertion time may improve lesion detection.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02078804.

Association between antispasmodics and detection of lesions by screening esophagogastroduodenoscopy

Background and Aim

Whether administration of antispasmodics as a component of premedication contributes to detection of lesions by screening esophagogastroduodenoscopy (EGDS) remains unclear. Our primary aim was to investigate this possibility.

Methods

The cohort in this retrospective study comprised consecutive asymptomatic individuals who had undergone screening EGDS as part of a health check‐up at the Japanese Red Cross Wakayama Medical Center from October 2015 to September 2020. The investigated lesions comprised esophageal squamous cell carcinoma or adenocarcinoma, gastric adenoma or adenocarcinoma, and duodenal adenoma or adenocarcinoma.

Results

Targeted lesions were detected in 72 of 31 484 participants (0.23%), 18 260 and 13 224 of whom had received and not received pre‐procedure antispasmodics, respectively. The rates of detection of lesions in these groups were 0.21% (38/18260) and 0.26% (34/13224), respectively (P = 0.40). Multivariate logistic regression analysis showed no association between administration of antispasmodics and rates of detection of targeted lesions [P = 0.24, Odds ratio (95% CI): 1.46 (0.78–2.75)].

Conclusions

Antispasmodics, which were administered to more than half of the study cohort, did not improve the rate of detection of targeted lesions.

Canadian Association of Gastroenterology (CAG) Position Statement on the Use of Hyoscine-n-butylbromide (Buscopan) During Gastrointestinal Endoscopy

Hyoscine butylbromide, also known as hyoscyamine or scopolamine, and sold under the trade name Buscopan, is an antimuscarinic agent commonly used to induce smooth muscle relaxation and reduce spasmodic activity of the gastrointestinal (GI) tract during endoscopic procedures. However, the balance between desirable and undesirable (adverse) effects is not clear when used during GI endoscopy. The Clinical Affairs Committee of the Canadian Association of Gastroenterology (CAG) conducted systematic reviews and applied the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations for the use of Buscopan during GI endoscopy. To summarize, we recommend against the use of Buscopan before or during colonoscopy (strong recommendation, high certainty of evidence). We suggest against the use of Buscopan before or during gastroscopy (conditional recommendation, very low certainty of evidence). We suggest the use of Buscopan before or during ERCP (conditional recommendation, very low certainty of evidence). More research is needed to determine whether patients undergoing advanced procedures such as endoscopic mucosal resection or endoscopic submucosal dissection benefit from its use. Buscopan should be used with caution in patients with cardiac comorbidities. According to its product monograph, Buscopan is contraindicated in patients with tachycardia, angina, and cardiac failure. Thus, Buscopan should be used very cautiously in patients with these conditions, and only when the potential benefits of its use outweigh the potential risks in a particular case. Such patients require careful cardiac monitoring in an environment where resuscitation equipment and appropriately trained staff to use it are readily available. According to its product monograph, Buscopan is also contraindicated in patients with prostatic hypertrophy with urinary retention, and therefore, should be used very cautiously in such patients as well, and only when the potential benefits of its use outweigh the potential risks in a particular case. Obtaining a preprocedural history of glaucoma is unlikely to be of value when considering Buscopan use. However, in cases where Buscopan has been used, patients should be counselled postprocedurally and told to present to an emergency facility should they experience eye pain, redness, decreased vision, nausea and vomiting or headache.

L-Menthol for Gastrointestinal Endoscopy: A Systematic Review and Meta-Analysis

In randomized controlled trials, L-menthol inhibits gastrointestinal peristalsis during endoscopy. Our goal was to quantitatively synthesize the available evidence to evaluate the efficacy and safety of L-menthol for gastrointestinal endoscopy.

Colonoscopy screening and surveillance guidelines

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

Standards of diagnostic colonoscopy for early-stage neoplasia: Recommendations by an Asian private group

BACKGROUND AND AIM

In recent years, the incidence of colorectal cancer has been increasing, and it is now becoming the major cause of cancer death in Asian countries. The aim of the present study was to develop Asian expert-based consensus to standardize the preparation, detection and characterization for the diagnosis of early-stage colorectal neoplasia.

METHODS

A professional group was formed by 36 experts of the Asian Novel Bio-Imaging and Intervention Group (ANBI² G) members. Representatives from 12 Asia-Pacific countries participated in the meeting. The group organized three consensus meetings focusing on diagnostic endoscopy for gastrointestinal neoplasia. The Delphi method was used to develop the consensus statements.

RESULTS

Through the three consensus meetings with debating, reviewing the literature and regional data, a consensus was reached at third meeting in 2016. The consensus was reached on a total of 10 statements. Summary of statements is as follows: (i) Adequate bowel preparation for high-quality colonoscopy; (ii) Antispasmodic agents for lesion detection; (iii) Image-enhanced endoscopy (IEE) for polyp detection; (iv) Adenoma detection rate for quality indicators; (v) Good documentation of colonoscopy findings; (vi) Complication rates; (vii) Cecal intubation rate; (viii) Cap-assisted colonoscopy (CAC) for polyp detection; (ix) Macroscopic classification using indigocarmine spray for characterization of colorectal lesions; and (x) IEE and/or magnifying endoscopy for prediction of histology.

CONCLUSION

This consensus provides guidance for carrying out endoscopic diagnosis and characterization for early-stage colorectal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early-stage colorectal neoplasia.

Choi C, Kim SJ, Nam HS, Ryu DG, Hong JB, Kim DJ. Cimetropium bromide does not improve polyp and adenoma detection during colonoscope withdrawal: A randomized, double-blind, placebo-controlled study

BACKGROUND

Endoscopic inspection of colonic mucosa is disturbed by colonic folds and peristalsis, which may result in missed polyps. Cimetropium bromide, an antispasmodic agent, inhibits peristalsis and colonic spasms, which may improve polyp detection. The purpose of this randomized, double-blind, placebo-controlled study was to investigate whether cimetropium bromide could improve polyp and adenoma detection in the colorectum and right colon.

METHODS

Patients undergoing screening or diagnostic colonoscopy were randomized to receive intravenous cimetropium bromide (5 mg) or placebo after cecal intubation. The primary outcomes were the number of polyps per patient (PPP) and adenomas per patient (APP); secondary outcomes were the polyp detection rate (PDR), adenoma detection rate (ADR), and advanced neoplasm detection rate (ANDR).

RESULTS

A total of 181 patients were analyzed; 91 patients received cimetropium bromide and 90 patients received placebo. Cimetropium bromide and placebo groups did not significantly differ in the PPP and APP for the colorectum (1.38 ± 1.58 vs 1.69 ± 2.28, P = .298; 0.96 ± 1.27 vs 1.11 ± 1.89, P = .517, respectively) and right colon (0.70 ± 0.95 vs 0.78 ± 1.21, P = .645; 0.47 ± 0.81 vs 0.51 ± 0.81, P = .757, respectively). Two groups also did not significantly differ in the PDR, ADR, and ANDR for the colorectum and right colon. Furthermore, there were no difference between groups in the PPP, APP, PDR, ADR, and ADNR in a sub-analysis of expert and non-expert endoscopists.

CONCLUSIONS

Cimetropium bromide did not improve polyp and adenoma detection in the colorectum and right colon during colonoscope withdrawal, regardless of the expertness of the endoscopist. However, its use may be helpful in patients with active peristalsis or for beginning endoscopists during standard colonoscopy without a transparent cap.

The NHS Bowel Cancer Screening Program: current perspectives on strategies for improvement

Colorectal cancer (CRC) is the third most common cancer in the UK. The English National Health Service (NHS) Bowel Cancer Screening Program (BCSP) was introduced in 2006 to improve CRC mortality by earlier detection of CRC. It is now offered to patients aged 60-74 years and involves a home-based guaiac fecal occult blood test (gFOBt) biennially, and if positive, patients are offered a colonoscopy. This has been associated with a 15% reduction in mortality. In 2013, an additional arm to BCSP was introduced, Bowelscope. This offers patients aged 55 years a one-off flexible sigmoidoscopy, and if several adenomas are found, the patients are offered a completion colonoscopy. BCSP has been associated with a significant stage shift in CRC diagnosis; however, the uptake of bowel cancer screening remains lower than that for other screening programs. Further work is required to understand the reasons for nonparticipation of patients to ensure optimal uptake. A change of gFOBt kit to the fecal immunochemical tests (FIT) in the English BCSP may further increase patient participation. This, in addition to increased yield of neoplasia and cancers with the FIT kit, is likely to further improve CRC outcomes in the screened population.

British Society of Gastroenterology position statement on serrated polyps in the colon and rectum

Serrated polyps have been recognised in the last decade as important premalignant lesions accounting for between 15% and 30% of colorectal cancers. There is therefore a clinical need for guidance on how to manage these lesions; however, the evidence base is limited. A working group was commission by the British Society of Gastroenterology (BSG) Endoscopy section to review the available evidence and develop a position statement to provide clinical guidance until the evidence becomes available to support a formal guideline. The scope of the position statement was wide-ranging and included: evidence that serrated lesions have premalignant potential; detection and resection of serrated lesions; surveillance strategies after detection of serrated lesions; special situations-serrated polyposis syndrome (including surgery) and serrated lesions in colitis; education, audit and benchmarks and research questions. Statements on these issues were proposed where the evidence was deemed sufficient, and re-evaluated modified via a Delphi process until >80% agreement was reached. The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) tool was used to assess the strength of evidence and strength of recommendation for finalised statements. Key recommendation: we suggest that until further evidence on the efficacy or otherwise of surveillance are published, patients with sessile serrated lesions (SSLs) that appear associated with a higher risk of future neoplasia or colorectal cancer (SSLs ≥10 mm or serrated lesions harbouring dysplasia including traditional serrated adenomas) should be offered a one-off colonoscopic surveillance examination at 3 years (weak recommendation, low quality evidence, 90% agreement).

Hyoscine butylbromide for colorectal polyp detection: prospective, randomized, placebo-controlled trial

OBJECTIVES:

The removal of pre-malignant colorectal lesions prevents cancer. Hyoscine has been proposed as a means of improving diagnosis by reducing colonic movements. The aim of this study was to analyze whether this anti-spasmodic enhances the detection of pre-malignant colorectal lesions.

METHODS:

In a randomized, double-blinded fashion patients received hyoscine or a saline solution in all consecutive colonoscopies in which the cecum was reached. Lesions were analysed with respect to number, size, location, histology and capillary pattern.

RESULTS:

A total of 440 colonoscopies were randomized. The overall polyp detection rate (PDR) and the adenoma detection rate (ADR) were 65.2% and 49.3%, respectively. In the hyoscine group, non-polypoid lesions were detected significantly more often (p=0.01). In the placebo group 281 lesions were diagnosed (202 adenomas) and in the hyoscine group 282 lesions were detected (189 adenomas) (p=0.23). The PDR and ADR were similar between the placebo and hyoscine groups (64% vs 66% and 50% vs 47%, respectively). No differences were observed between the two groups in the advanced-ADR or advanced neoplasia detection rate, as well the mean numbers of polyps, adenomas, advanced adenomas and advanced neoplasias detected per patient. The administration of hyoscine also did not improve the diagnostic accuracy of digital chromoendoscopy. The presence of adenomatous polyps in the right colon was detected significantly more frequently in the hyoscine group (OR 5.41 95% CI 2.7 - 11; p<0.01 vs OR 2.3 95% CI 1.1 - 4.6; p=0.02).

CONCLUSION:

The use of hyoscine before beginning the withdrawal of the colonoscope does not seem to enhance the PDR and the ADR.

Improvement of Quality of Nonanesthetic Colonoscopy by Preoperative Administration of Pinaverium Bromide

Background:

Nonanesthetic colonoscopy is popular in clinical practice in China. However, intestinal spasms often result in a prolonged examination time, increased operating difficulties, decreased polyp detection rate, and failure to complete the procedure clinically. Therefore, exploring alternative approaches that can reduce the pain in patients during colonoscopy is of utmost importance, and finding the optimal preoperative administration to improve the quality of nonanesthetic colonoscopy is also necessary. This study aimed to investigate the effects of the prophylactic administration of pinaverium bromide before colonoscopy and the effects of pinaverium bromide alone at different time points or combined with scopolamine butylbromide.

Methods:

A randomized controlled trial was performed on a cohort of 1000 patients who underwent colonoscopy in outpatient clinic of Wuhan Union Hospital. The patients were randomly assigned to the following groups: Group A, given oral pinaverium bromide (100 mg, three times a day) one day before examination combined with intramuscular injection of scopolamine butylbromide (20 mg) 10 min before colonoscopy; Group B₀, given pinaverium bromide alone on the day of colonoscopy (100 mg, three times a day); Group B₁, given pinaverium bromide alone (100 mg, three times a day) one day before colonoscopy; Group B₂, given pinaverium bromide alone (100 mg, three times a day) two days before colonoscopy; and Group C, given scopolamine butylbromide alone (20 mg) before colonoscopy. The successful rate of colonoscopy, procedure time, degree of abdominal pain, and polyp detection rate were recorded and compared among all groups.

Results:

The successful rate of colonoscopy in Group B₁ (82.0%) and Group B₂ (83.0%) was significantly higher than that in Group B₀ (62.0%, all P < 0.01). The time to reach the ileocecal region in Group B₁ and Group B₂ were lower than those in Group B₀ (all P < 0.05). However, no significant differences were observed in polyp detection rate between Group B₁ (24.0%) or Group B₂ (26.0%), and Group B₀ (22.4%, all P > 0.05). Furthermore, there were no significant differences in the various parameters examined between Group B₁ and Group B₂ (P > 0.05). The successful rate of colonoscopy in Group A (92.0%) was significantly higher than that in Group B₁ (82.0%) and Group C (80.0%; both P < 0.05). Moreover, the time for the colonoscope to reach the ileocecal region in Group A were markedly shorter as compared to those in Group B₁ and Group C (P < 0.05). The polyp detection rate in Group A was 32.0%, significantly higher than that in Group B₁ (24.0%, P < 0.05) and Group C (24.2%, P < 0.05).

Conclusion:

Administration of pinaverium bromide alone one day before examination was beneficial to relieve symptoms of abdominal pain during nonanesthetic colonoscopy. In addition, therapeutic effects were improved when pinaverium bromide administration was combined with intramuscular injection of scopolamine butylbromide. Therefore, the combined use of pinaverium bromide with scopolamine butylbromide might have great application value to improve the quality of nonanesthetic colonoscopy in the preoperative preparation.

Strategies to Increase Adenoma Detection Rates

OPINION STATEMENT

The adenoma detection rate (ADR), i.e., the proportion of average risk patients with at least one adenoma detected during screening colonoscopy, is inversely associated with the development of interval colorectal cancer. Increasing the ADR is therefore an important proxy for increase in quality and efficacy of (screening) colonoscopy. Several potentially modifiable factors, such as, procedural and technological factors, and quality improvement programs, and their effect on the ADR will be reviewed. Procedural factors, such as, bowel preparation, withdrawal time, and position changes of the patient are associated with the ADR. While the relation of others, such as inspection during insertion, use of antispasmodic agents, and second inspection in the proximal colon, with the ADR is not completely clear. Many new colonoscopy technologies have been evaluated over recent years and are still under evaluation, but no unequivocal positive effect on the ADR has been observed in randomized trials that have mostly been performed by experienced endoscopists with high baseline ADRs. Several quality improvement programs have been evaluated and seem to have a positive effect on endoscopists' ADR. Increase in ADR is important for the protective benefit of colonoscopy. There are now extensive methods to measure, benchmark, and improve ADR but increased awareness of these is critical. We have provided an overview of potential factors that can be used to increase personal ADRs in every day practice.

Antispasmodic drugs in colonoscopy: a review of their pharmacology, safety and efficacy in improving polyp detection and related outcomes

Antispasmodic drugs are cheap, effective and generally safe. They may improve outcomes in colonoscopy, however their use has not been consistent or widespread. This manuscript reviews the three most commonly used antispasmodics in colonoscopy, namely, hyoscine butylbromide (and related ammonium compounds), glucagon and peppermint oil. The pharmacology, action and safety of the agents, as well as the evidence for them improving colonoscopic outcomes will be discussed. In addition to polyp detection, other colonoscopic outcome endpoints of interest include cecal and ileal intubation, and patient comfort. The drugs studied were all found to be effective gastrointestinal antispasmodics with good safety profiles. There is insufficient evidence to conclude whether antispasmodics improve cecal intubation rate, predominantly because the baseline rates are already high. Antispasmodics probably have efficacy in reducing cecal intubation time especially in those with marked colonic spasm. Antispasmodics do not offer significant benefit in polyp detection or improving patient comfort during colonoscopy. Future studies should focus on inexperienced colonoscopists as well as those with marked colonic spasm, in whom the greatest benefit seems to lie.

Technical interventions to increase adenoma detection rate in colonoscopy

Adenoma detection rate (ADR) is the most robust colonoscopy quality metric and clinical studies have adopted it as the ideal method to assess the impact of technical interventions. Areas covered: We reviewed papers focusing on the impact of colonoscopy technical issues on ADR, including withdrawal time and technique, second evaluation of the right colon, patient positional changes, gastrointestinal assistant participation during colonoscopy, water-aided technique, optimization of bowel preparation and antispasmodic administration. Expert commentary: Overall, technical interventions are inexpensive, available worldwide and easy to implement. Some of them, such as the adoption of split dose regimen and slow scope withdrawal to allow a careful inspection, have been demonstrated to significantly improve ADR. Emerging data support the use of water-exchange colonoscopy. According to published studies, other technical interventions seem to provide only marginal benefit to ADR. Unfortunately, the available evidence has methodological limitations, such as small sample sizes, the inclusion of expert endoscopists only and the evaluation of single technical interventions. Additionally, larger studies are needed to clarify whether these interventions might have a higher benefit on low adenoma detectors and whether the implementation of a bundle of them, instead of a single technical maneuver, might have a greater impact on ADR.

Expert opinions and scientific evidence for colonoscopy key performance indicators

Colonoscopy is a widely performed procedure with procedural volumes increasing annually throughout the world. Many procedures are now performed as part of colorectal cancer screening programmes. Colonoscopy should be of high quality and measures of this quality should be evidence based. New UK key performance indicators and quality assurance standards have been developed by a working group with consensus agreement on each standard reached. This paper reviews the scientific basis for each of the quality measures published in the UK standards.

Quantitative assessment of the effect of position changes during colonoscopy withdrawal

OBJECTIVE

Although trials assessing the effectiveness of position changes during colonoscopy withdrawal have been reported, there has been no agreement whether such position changes actually improve the polyp detection rate (PDR) or adenoma detection rate (ADR). This article aimed to address this issue by performing a systematic review.

METHODS

Relevant studies from databases including PubMed, EMBASE and the Cochrane Library and Science Citation Index were retrieved. Two reviewers independently identified potentially relevant studies. Outcome measures were PDR, ADR and bowel distention.

RESULTS

Eight studies were included, of which seven were randomized controlled trials (RCTs). A non-randomized controlled trial and all four cross-over RCTs reported significant improvement in PDR, ADR and bowel distention with position change during colonoscopic withdrawal, while three parallel-group RCTs did not confirm its effectiveness.

CONCLUSIONS

The conflicting results of high-quality trials indicate that the effectiveness of position change during colonoscopy withdrawal on PDR, ADR and bowel distension is uncertain. Thus, position change during colonoscopy withdrawal should not be routinely applied until future studies demonstrate its efficacy.

The role of routinely given hyoscine-N-butylbromide in colonoscopy: a double-blind, randomized, placebo-controlled, clinical trial

OBJECTIVE

Hyoscine-N-butylbromide (HBB) has been proposed to ease colonoscopy and improve mucosal visualization, yet the results from previous studies are conflicting. In our prospective, double-blind, placebo-controlled, randomized study we aimed at evaluating whether routine administration of HBB, before and during colonoscopy, ease the procedure or increase the detection rate for polyps.

MATERIAL AND METHODS

One hundred fifty outpatients scheduled for an elective colonoscopy were randomized to receive intravenous injections of either 10 mg hyoscine-N-butylbromide or saline before insertion and at cecum. Patient tolerance and technical ease of colonoscopy were evaluated by visual analogue scale (VAS). Procedure times were recorded. Number of detected polyps per patient was evaluated as well. Heart rate was monitored with a pulse oximetry.

RESULTS

HBB did not improve patient tolerance or technically ease the procedure as evaluated by VAS. However, HBB led to faster ileal intubation (1.5 vs 2.0 min, p < 0.001) and shorter total procedure time (22.0 vs 24.0 min, p = 0.03). Patients who received HBB also needed less often external abdominal pressure (48.6 vs 66.7%, p = 0.03). HBB did not improve polyp detection rate (0.89 vs 0.91, p = 0.90). HBB induced a significant rise in heart rate (p < 0.001) and more often tachycardia (17.6 vs 0%, p < 0.001).

CONCLUSIONS

Routine administration of HBB before and during colonoscopy yields only limited improvement in the technical performance of the examination compromised by high incidence of tachycardia.

Seeing better - Evidence based recommendations on optimizing colonoscopy adenoma detection rate

Colorectal cancer is one of the three most frequent causes of cancer deaths in men and women in Europe and North America. Diagnosis and resection of adenomas has convincingly demonstrated its utility in diminishing colorectal cancer incidence. Therefore, colonoscopy is now the gold standard for colorectal cancer screening. But it is also known that colonoscopy effectiveness varies among endoscopists. Among different quality indicators, the most used is the adenoma detection rate (ADR) which is the percentage of average-risk patients for colorectal cancer who are found to have at least one adenoma or adenocarcinoma during a screening colonoscopy. There is compelling evidence supporting an inverse correlation between ADR and interval colorectal cancer (cancer found after a screening colonoscopy). Many factors such as quality of precolonoscopy preparation, additional observers, manoeuvres with the endoscope (second view, retroflexion, water inflation rather than air), time spent during withdrawal, changes in patient position, fold-flattener devices, new imaging or endoscopic modalities and use of intravenous or through the scope sprayed drugs, have been studied and developed with the aim of increasing the ADR. This reviews discusses these factors, and the current evidence, to “see better” in the colon and optimize ADR.

Improving the utility of colonoscopy: Recent advances in practice

Colonoscopy is a frequently performed diagnostic and therapeutic test and the primary screening tool in several nationalized bowel cancer screening programs. There has been a considerable focus on maximizing the utility of colonoscopy. This has occurred in four key areas: Optimizing patient selection to reduce unnecessary or low yield colonoscopy has offered cost-benefit improvements in population screening. Improving quality assurance, through the development of widely accepted quality metrics for use in individual practice and the research setting, has offered measurable improvements in colonoscopic yield. Significant improvements have been demonstrated in colonoscopic technique, from the administration of preparation to the techniques employed during withdrawal of the colonoscope. Improved techniques to avoid post-procedural complications have also been developed-further maximizing the utility of colonoscopy. The aim of this review is to summarize the recent evidence-based advances in colonoscopic practice that contribute to the optimal practice of colonoscopy.

Mechanisms of hyoscine butylbromide to improve adenoma detection: A case-control study of surface visualization at simulated colonoscope withdrawal

BACKGROUND AND STUDY AIMS

Antispasmodics may improve mucosal visualization during colonoscope withdrawal, potentially improving polyp and adenoma detection. Meta-analysis and case-control studies suggest a 9 % to 13 % relative increase in adenoma and polyp detection. We aimed to assess the impact of hyoscine butylbromide on the expected visualization during colonoscope withdrawal using a CT colonography (CTC) simulation.

PATIENTS AND METHODS

Datasets from a previous CTC study examining the effect of antispasmodic were re-analyzed with customised CTC software, adjusted to simulate a standard colonoscopic view. Eighty-six patients received intravenous (IV) hyoscine butylbromide 20 mg, 40 mg or no antispasmodic. Main outcome measurements at unidirectional flythrough, simulating colonoscope withdrawal, were percentage colonic surface visualization, numbers and sizes of unseen areas, and colonic length.

RESULTS

Use of antispasmodic was associated with a significant relative increase in percentage surface visualization of 2.6 % to 3.9 %, compared with no antispasmodic, P < 0.006. Total numbers of missed areas and intermediate sized (300 - 1000 mm(2)) missed areas were significantly decreased, by approximately 20 %. There were no differences between the 20-mg and 40-mg doses. Mean colonic length (161 - 169 cm) was unchanged by antispasmodic.

CONCLUSIONS

IV hyoscine butylbromide at simulated colonoscope withdrawal was associated with significant increases in surface visualization, which might explain up to half the improvement in adenoma detection seen in clinical studies.

Water infusion versus air insufflation for colonoscopy

BACKGROUND

Colonoscopy is a widely used diagnostic and therapeutic modality. A large proportion of the population is likely to undergo colonoscopy for diagnosis and treatment of colorectal diseases, or when participating in colorectal cancer screening programs. To reduce pain, water infusion instead of traditional air insufflation during the insertion phase of the colonoscopy has been proposed, thereby improving patients' acceptance of the procedure. Moreover, the water infusion method may improve early detection of precancerous neoplasms.

OBJECTIVES

To compare water infusion techniques with standard air insufflation, specifically evaluating technical quality and screening efficacy, as well as patients' acceptance of the water infusion procedure.

SEARCH METHODS

We searched the Cochrane Colorectal Cancer Group Specialized Register (February 2014), the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 1), Ovid MEDLINE (1950 to February 2014), Ovid EMBASE (1974 to February 2014), and ClinicalTrials.gov (1999 to February 2014) for eligible randomised controlled trials.

SELECTION CRITERIA

We included randomised controlled trials comparing water infusion (water exchange or water immersion methods) against standard air insufflation during the insertion phase of the colonoscopy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for inclusion and extracted data from eligible studies. We performed analysis using Review Manager software (RevMan 5).

MAIN RESULTS

We included 16 randomised controlled trials consisting of 2933 colonoscopies. Primary outcome measures were cecal intubation rate and adenoma detection; secondary outcomes were time needed to reach the cecum, pain experienced by participants during the procedure, completion of cecal intubation without sedation/analgesia, and adverse events. Completeness of colonoscopy, that is cecal intubation rate, was similar between water infusion and standard air insufflation (risk ratio 1.00, 95% confidence interval (CI) 0.97 to 1.03, P = 0.93). Adenoma detection rate, that is number of participants with at least one detected adenoma, was slightly improved with water infusion (risk ratio 1.16, 95% CI 1.04 to 1.30, P = 0.007). Assuming the fraction of patients undergoing screening colonoscopy who had one or more adenomas detected was 20 per 100 with standard colonoscopy, the use of water colonoscopy may increase the fraction to 23 per 100 individuals. From our findings, it is possible that up to 68,000 more of the 1.7 million outpatient screening colonoscopies performed annually in the United States, could detect adenomas if water infusion colonoscopy was used. In addition, with water infusion participants experienced significantly less pain (mean difference in pain score on a 0 to 10 scale: -1.57, 95% CI -2.00 to -1.14, P < 0.00001) and a significantly lower proportion of participants requested on-demand sedation or analgesia, or both (risk ratio 1.20, 95% CI 1.14 to 1.27, P < 0.00001). Qualitative analysis suggests that water infusion colonoscopy was not associated with a markedly increased rate of adverse events compared with the standard procedure.

AUTHORS' CONCLUSIONS

Completeness of colonoscopy, that is cecal intubation rate, was not improved by water infusion compared with standard air insufflation colonoscopy. However, adenoma detection, assessed with two different measures (that is adenoma detection rate and number of detected adenomas per procedure), was slightly augmented by the water infusion colonoscopy. Improved adenoma detection might be due to the cleansing effects of water infusions on the mucosa. Detection of premalignant lesions during standard colonoscopy is suboptimal, and so improvements in adenoma detection by water infusion colonoscopy, although small, may help to reduce the risk of interval colorectal carcinoma. The most obvious benefit of water infusion colonoscopy was reduction of procedure-related abdominal pain, which may enhance the acceptance of screening/surveillance colonoscopy.

Techniques and technologies to maximize mucosal exposure

Performing high-quality colonoscopy is one of the important goals of gastroenterology practices and requires achieving a high level of bowel cleansing, performing good and safe polypectomy, and detecting all polyps present in the colon. This article summarizes currently available techniques and technologies to maximize mucosal visualization. Several maneuvers can be applied during insertion and withdrawal of the colonoscope to optimize mucosal visualization and decrease the number of missed polyps. Newly developed technologies support the endoscopist in the detection of polyps. Each technique is reviewed, with emphasis on the impact on colorectal polyp detection.