British Society of Gastroenterology guidelines on sedation in gastrointestinal endoscopy.

Over 2.5 million gastrointestinal endoscopic procedures are carried out in the United Kingdom (UK) every year. Procedures are carried out with local anaesthetic r with sedation. Sedation is commonly used for gastrointestinal endoscopy, but the type and amount of sedation administered is influenced by the complexity and nature of the procedure and patient factors. The elective and emergency nature of endoscopy procedures and local resources also have a significant impact on the delivery of sedation. In the UK, the vast majority of sedated procedures are carried out using benzodiazepines, with or without opiates, whereas deeper sedation using propofol or general anaesthetic requires the involvement of an anaesthetic team. Patients undergoing gastrointestinal endoscopy need to have good understanding of the options for sedation, including the option for no sedation and alternatives, balancing the intended aims of the procedure and reducing the risk of complications. These guidelines were commissioned by the British Society of Gastroenterology (BSG) Endoscopy Committee with input from major stakeholders, to provide a detailed update, incorporating recent advances in sedation for gastrointestinal endoscopy.This guideline covers aspects from pre-assessment of the elective 'well' patient to patients with significant comorbidity requiring emergency procedures. Types of sedation are discussed, procedure and room requirements and the recovery period, providing guidance to enhance safety and minimise complications. These guidelines are intended to inform practising clinicians and all staff involved in the delivery of gastrointestinal endoscopy with an expectation that this guideline will be revised in 5-years' time.

Life cycle assessment of routinely used endoscopic instruments and simple intervention to reduce our environmental impact.

OBJECTIVES: GI endoscopy units represent the third largest producers of medical waste. We aimed to determine endoscopic instrument composition and life cycle assessment (LCA) and to assess a sustainability proposal based on a mark on the instruments that identifies parts can be safely recycled or 'green mark'. DESIGN: Material composition analysis and LCA of forceps, snares and clips from four different manufacturers (A-D) were performed with four different methods. Carbon footprint from production, transportation and end of life of these instruments was calculated. In 30 consecutive procedures, we marked the contact point with the working channel. 5 cm away from that point was considered as green mark. One-week prospective study was conducted with 184 procedures evaluating 143 instruments (75 forceps, 49 snares and 19 haemoclips) to assess the efficacy of this recyclable mark. RESULTS: Composition from different manufacturers varied widely. Most common materials were high global warming potential (GWP) waste (polyethylene, polypropylene and acrylonitrile) and low GWP waste (stainless steel). Significant differences were found for the forceps (0.31-0.47 kg of CO2 equivalent (CO2-eq)) and haemoclips (0.41-0.57 kg CO2-eq) between the manufacturers. Green mark was established 131.26 cm for gastroscope and 195.32 cm for colonoscope. One-week activity produced 67.74 kg CO2-eq. Applying our sustainability intervention, we could reduce up to 27.44% (18.26 kg CO2-eq). This allows the recycling of 61.7% of the instrument total weight (4.69 kg). CONCLUSION: Knowledge of carbon footprint is crucial to select the most sustainable alternatives because there are large variations between brands. A mark to identify recyclable parts could reduce our environmental impact significantly.

Smart capsules for sensing and sampling the gut: status, challenges and prospects.

Smart capsules are developing at a tremendous pace with a promise to become effective clinical tools for the diagnosis and monitoring of gut health. This field emerged in the early 2000s with a successful translation of an endoscopic capsule from laboratory prototype to a commercially viable clinical device. Recently, this field has accelerated and expanded into various domains beyond imaging, including the measurement of gut physiological parameters such as temperature, pH, pressure and gas sensing, and the development of sampling devices for better insight into gut health. In this review, the status of smart capsules for sensing gut parameters is presented to provide a broad picture of these state-of-the-art devices while focusing on the technical and clinical challenges the devices need to overcome to realise their value in clinical settings. Smart capsules are developed to perform sensing operations throughout the length of the gut to better understand the body's response under various conditions. Furthermore, the prospects of such sensing devices are discussed that might help readers, especially health practitioners, to adapt to this inevitable transformation in healthcare. As a compliment to gut sensing smart capsules, significant amount of effort has been put into the development of robotic capsules to collect tissue biopsy and gut microbiota samples to perform in-depth analysis after capsule retrieval which will be a game changer for gut health diagnosis, and this advancement is also covered in this review. The expansion of smart capsules to robotic capsules for gut microbiota collection has opened new avenues for research with a great promise to revolutionise human health diagnosis, monitoring and intervention.

UK and Ireland Joint Advisory Group (JAG) consensus statements for training and certification in diagnostic endoscopic ultrasound (EUS).

BACKGROUND AND AIMS: International endoscopy societies vary in their approach for credentialing individuals in endoscopic ultrasound (EUS) to enable independent practice; however, there is no consensus in this or its implementation. In 2019, the Joint Advisory Group on GI Endoscopy (JAG) commissioned a working group to examine the evidence relating to this process for EUS. The aim of this was to develop evidence-based recommendations for EUS training and certification in the UK. METHODS: Under the oversight of the JAG quality assurance team, a modified Delphi process was conducted which included major stakeholders from the UK and Ireland. A formal literature review was made, initial questions for study were proposed and recommendations for training and certification in EUS were formulated after a rigorous assessment using the Grading of Recommendation Assessment, Development and Evaluation tool and subjected to electronic voting to identify accepted statements. These were peer reviewed by JAG and relevant stakeholder societies before consensus on the final EUS certification pathway was achieved. RESULTS: 39 initial questions were proposed of which 33 were deemed worthy of assessment and finally formed the key recommendations. The statements covered four key domains, such as: definition of competence (13 statements), acquisition of competence (10), assessment of competence (5) and postcertification mentorship (5). Key recommendations include: (1) minimum of 250 hands-on cases before an assessment for competency can be made, (2) attendance at the JAG basic EUS course, (3) completing a minimum of one formative direct observation of procedural skills (DOPS) every 10 cases to allow the learning curve in EUS training to be adequately studied, (4) competent performance in summative DOPS assessments and (5) a period of mentorship over a 12-month period is recommended as minimum to support and mentor new service providers. CONCLUSIONS: An evidence-based certification pathway has been commissioned by JAG to support and quality assure EUS training. This will form the basis to improve quality of training and safety standards in EUS in the UK and Ireland.

Gastric per-oral endoscopic myotomy (G-POEM) for refractory gastroparesis: results from an international prospective trial.

OBJECTIVE: Although gastric per-oral endoscopic myotomy (G-POEM) is considered a promising technique for the management of refractory gastroparesis, high-quality evidence is limited. We prospectively investigated the efficacy and safety of G-POEM in unselected patients with refractory gastroparesis. DESIGN: In five tertiary centres, patients with symptomatic gastroparesis refractory to standard medical therapy and confirmed by impaired gastric emptying were included. The primary endpoint was clinical success, defined as at least one score decrease in Gastroparesis Cardinal Symptom Index (GCSI) with ≥25% decrease in two subscales, at 12 months. GCSI Score and subscales, adverse events (AEs) and 36-Item Short Form questionnaire of quality of life were evaluated at baseline and 1, 3, 6 and 12 months after G-POEM. Gastric emptying study was performed before and 3 months after the procedure. RESULTS: Of 80 enrolled patients, 75 patients (94%) completed 12-month follow-up. Clinical success at 12 months was 56% (95% CI, 44.8 to 66.7). GCSI Score (including subscales) improved moderately after G-POEM (p<0.05). In a regression model, a baseline GCSI Score >2.6 (OR=3.23, p=0.04) and baseline gastric retention >20% at 4 hours (OR=3.65, p=0.03) were independent predictors of clinical success at 12 months, as was early response to G-POEM at 1 month after therapy (OR 8.75, p<0.001). Mild procedure-related AEs occurred in 5 (6%) patients. CONCLUSION: G-POEM is a safe procedure, but showed only modest overall effectiveness in the treatment of refractory gastroparesis. Further studies are required to identify the best candidates for G-POEM; unselective use of this procedure should be discouraged. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry NCT02732821.

Timing of endoscopy for acute upper gastrointestinal bleeding: a territory-wide cohort study.

OBJECTIVE: While it is recommended that patients presenting with acute upper gastrointestinal bleeding (AUGIB) should receive endoscopic intervention within 24 hours, the optimal timing is still uncertain. We aimed to assess whether endoscopy timing postadmission would affect outcomes. DESIGN: We conducted a retrospective, territory-wide, cohort study with healthcare data from all public hospitals in Hong Kong. Adult patients (age ≥18) that presented with AUGIB between 2013 and 2019 and received therapeutic endoscopy within 48 hours (n=6474) were recruited. Patients were classified based on endoscopic timing postadmission: urgent (t≤6), early (6

Endoscopic placement of covered versus uncovered self-expandable metal stents for palliation of malignant gastric outlet obstruction.

OBJECTIVE: Stenting is an established endoscopic therapy for malignant gastric outlet obstruction (mGOO). The choice of stent (covered vs uncovered) has been examined in prior randomised studies without clear results. DESIGN: In a multicentre randomised prospective study, we compared covered (CSEMS) with uncovered self-expandable metal stents (UCSEMS) in patients with mGOO; main outcomes were stent dysfunction and patient survival, with subgroup analyses of patients with extrinsic and intrinsic tumours. RESULTS: Overall survival was poor with no difference between groups (probability at 3 months 49.7% for covered vs 48.4% for uncovered stents; log-rank for overall survival p=0.26). Within that setting of short survival, the proportion of stent dysfunction was significantly higher for uncovered stents (35.2% vs 23.4%, p=0.01) with significantly shorter time to stent dysfunction. This was mainly relevant for patients with extrinsic tumours (stent dysfunction rates for uncovered stents 35.6% vs 17.5%, p<0.01). Subgrouping was also relevant with respect to tumour ingrowth (lower with covered stents for intrinsic tumours; 1.6% vs 27.7%, p<0.01) and stent migration (higher with covered stents for extrinsic tumours: 15.3% vs 2.5%, p<0.01). CONCLUSIONS: Due to poor patient survival, minor differences between covered and uncovered stents may be less relevant even if statistically significant; however, subgroup analysis would suggest to use covered stents for intrinsic and uncovered stents for extrinsic malignancies.

Full-field optical coherence tomography: novel imaging technique for extemporaneous high-resolution analysis of mucosal architecture in human gut biopsies.

Full-field optical coherence tomography (FFOCT) is an imaging technique of biological tissue based on tissue light reflectance analysis. We evaluated the feasibility of imaging fresh digestive mucosal biopsies after a quick mounting procedure (5 min) using two distinct modalities of FFOCT. In static FFOCT mode, we gained high-resolution images of general gut tissue-specific architecture, such as oesophageal papillae, gastric pits, duodenal villi and colonic crypts. In dynamic FFOCT mode, we imaged individual epithelial cells of the mucosal lining with a cellular or subcellular resolution and identified cellular components of the lamina propria. FFOCT represents a promising dye-free imaging tool for on-site analysis of gut tissue remodelling.

Novel scheme for non-invasive gut bioinformation acquisition with a magnetically controlled sampling capsule endoscope.

OBJECTIVE: Intestinal flora and metabolites are associated with multiple systemic diseases. Current approaches for acquiring information regarding microbiota/metabolites have limitations. We aimed to develop a precise magnetically controlled sampling capsule endoscope (MSCE) for the convenient, non-invasive and accurate acquisition of digestive bioinformation for disease diagnosis and evaluation. DESIGN: The MSCE and surgery were both used for sampling both jejunal and ileal GI content in the control and antibiotic-induced diarrhoea groups. The GI content was then used for microbiome profiling and metabolomics profiling. RESULTS: Compared with surgery, our data showed that the MSCE precisely acquired data regarding the intestinal flora and metabolites, which was effectively differentiated in different intestinal regions and disease models. Using MSCE, we detected a dramatic decrease in the abundance of Bacteroidetes, Patescibacteria and Actinobacteria and hippuric acid levels, as well as an increase in the abundance of Escherichia-Shigella and the 2-pyrrolidinone levels were detected in the antibiotic-induced diarrhoea model by MSCE. MSCE-mediated sampling revealed specific gut microbiota/metabolites including Enterococcus, Lachnospiraceae, acetyl-L-carnitine and succinic acid, which are related to metabolic diseases, cancers and nervous system disorders. Additionally, the MSCE exhibited good sealing characteristics with no contamination after sampling. CONCLUSIONS: We present a newly developed MSCE that can non-invasively and accurately acquire intestinal bioinformation via direct visualization under magnetic control, which may further aid in disease prevention, diagnosis, prognosis and treatment.

Piecemeal cold snare polypectomy versus conventional endoscopic mucosal resection for large sessile serrated lesions: a retrospective comparison across two successive periods.

OBJECTIVE: Large (≥20 mm) sessile serrated lesions (L-SSL) are premalignant lesions that require endoscopic removal. Endoscopic mucosal resection (EMR) is the existing standard of care but carries some risk of adverse events including clinically significant post-EMR bleeding and deep mural injury (DMI). The respective risk-effectiveness ratio of piecemeal cold snare polypectomy (p-CSP) in L-SSL management is not fully known. DESIGN: Consecutive patients referred for L-SSL management were treated by p-CSP from April 2016 to January 2020 or by conventional EMR in the preceding period between July 2008 and March 2016 at four Australian tertiary centres. Surveillance colonoscopies were conducted at 6 months (SC1) and 18 months (SC2). Outcomes on technical success, adverse events and recurrence were documented prospectively and then compared retrospectively between the subsequent time periods. RESULTS: A total of 562 L-SSL in 474 patients were evaluated of which 156 L-SSL in 121 patients were treated by p-CSP and 406 L-SSL in 353 patients by EMR. Technical success was equal in both periods (100.0% (n=156) vs 99.0% (n=402)). No adverse events occurred in p-CSP, whereas delayed bleeding and DMI were encountered in 5.1% (n=18) and 3.4% (n=12) of L-SSL treated by EMR, respectively. Recurrence rates following p-CSP were similar to EMR at 4.3% (n=4) versus 4.6% (n=14) and 2.0% (n=1) versus 1.2% (n=3) for surveillance colonoscopy (SC)1 and SC2, respectively. CONCLUSIONS: In a historical comparison on the endoscopic management of L-SSL, p-CSP is technically equally efficacious to EMR but virtually eliminates the risk of delayed bleeding and perforation. p-CSP should therefore be considered as the new standard of care for L-SSL treatment.

Impact of the COVID-19 pandemic on UK endoscopic activity and cancer detection: a National Endoscopy Database Analysis.

OBJECTIVE: The COVID-19 pandemic has had a major global impact on endoscopic services. This reduced capacity, along with public reluctance to undergo endoscopy during the pandemic, might result in excess mortality from delayed cancer diagnosis. Using the UK's National Endoscopy Database (NED), we performed the first national analysis of the impact of the pandemic on endoscopy services and endoscopic cancer diagnosis. DESIGN: We developed a NED COVID-19 module incorporating procedure-level data on all endoscopic procedures. Three periods were designated: pre-COVID (6 January 2020 to 15 March), transition (16-22 March) and COVID-impacted (23 March-31 May). National, regional and procedure-specific analyses were performed. The average weekly number of cancers, proportion of missing cancers and cancer detection rates were calculated. RESULTS: A weekly average of 35 478 endoscopy procedures were performed in the pre-COVID period. Activity in the COVID-impacted period reduced to 12% of pre-COVID levels; at its low point, activity was only 5%, recovering to 20% of pre-COVID activity by study end. Although more selective vetting significantly increased the per-procedure cancer detection rate (pre-COVID 1.91%; COVID-impacted 6.61%; p<0.001), the weekly number of cancers detected decreased by 58%. The proportion of missing cancers ranged from 19% (pancreatobiliary) to 72% (colorectal). CONCLUSION: This national analysis demonstrates the remarkable impact that the pandemic has had on endoscopic services, which has resulted in a substantial and concerning reduction in cancer detection. Major, urgent efforts are required to restore endoscopy capacity to prevent an impending cancer healthcare crisis.

WASh multicentre randomised controlled trial: water-assisted sigmoidoscopy in English NHS bowel scope screening.

OBJECTIVES: The English Bowel Cancer Screening Programme invites 55 year olds for a sigmoidoscopy (Bowel Scope Screening (BSS)), aiming to resect premalignant polyps, thus reducing cancer incidence. A national patient survey indicated higher procedural pain than anticipated, potentially impacting on screening compliance and effectiveness. We aimed to assess whether water-assisted sigmoidoscopy (WAS), as opposed to standard CO2 technique, improved procedural pain and detection of adenomatous polyps. DESIGN: The WASh (Water-Assisted Sigmoidoscopy) trial was a multicentre, single-blind, randomised control trial for people undergoing BSS. Participants were randomised to either receive WAS or CO2 from five sites across England. The primary outcome measure was patient-reported moderate/severe pain, as assessed by patients on a standard Likert scale post procedure prior to discharge. The key secondary outcome was adenoma detection rate (ADR). The costs of each technique were also measured. RESULTS: 1123 participants (50% women, mean age 55) were randomised (561 WAS, 562 CO2). We found no difference in patient-reported moderate/severe pain between WAS and CO2 (14% in WAS, 15% in CO2; p=0.47). ADR was 15% in the CO2 arm and 11% in the WAS arm (p=0.03); however, it remained above the minimum national performance standard in both arms. There was no statistical difference in mean number of adenomas nor overall polyp detection rate. There was negligible cost difference between the two techniques. CONCLUSION: In the context of enema-prepared unsedated screening sigmoidoscopies performed by screening-accredited endoscopists, no difference in patient-reported pain was seen when using either a CO2 or WAS intubation technique. TRIAL REGISTRATION NUMBER: ISRCTN81466870.

Machine learning in GI endoscopy: practical guidance in how to interpret a novel field.

There has been a vast increase in GI literature focused on the use of machine learning in endoscopy. The relative novelty of this field poses a challenge for reviewers and readers of GI journals. To appreciate scientific quality and novelty of machine learning studies, understanding of the technical basis and commonly used techniques is required. Clinicians often lack this technical background, while machine learning experts may be unfamiliar with clinical relevance and implications for daily practice. Therefore, there is an increasing need for a multidisciplinary, international evaluation on how to perform high-quality machine learning research in endoscopy. This review aims to provide guidance for readers and reviewers of peer-reviewed GI journals to allow critical appraisal of the most relevant quality requirements of machine learning studies. The paper provides an overview of common trends and their potential pitfalls and proposes comprehensive quality requirements in six overarching themes: terminology, data, algorithm description, experimental setup, interpretation of results and machine learning in clinical practice.

BowelScope: Accuracy of Detection Using Endocuff Optimisation of Mucosal Abnormalities (the B-ADENOMA Study): a multicentre, randomised controlled flexible sigmoidoscopy trial.

OBJECTIVES: Adenoma detection rate (ADR) is an important quality marker at lower GI endoscopy. Higher ADRs are associated with lower postcolonoscopy colorectal cancer rates. The English flexible sigmoidoscopy (FS) screening programme (BowelScope), offers a one-off FS to individuals aged 55 years. However, variation in ADR exists. Large studies have demonstrated improved ADR using Endocuff Vision (EV) within colonoscopy screening, but there are no studies within FS. We sought to test the effect of EV on ADR in a national FS screening population. DESIGN: BowelScope: Accuracy of Detection Using ENdocuff Optimisation of Mucosal Abnormalities was a multicentre, randomised controlled trial involving 16 English BowelScope screening centres. Individuals were randomised to Endocuff Vision-assisted BowelScope (EAB) or Standard BowelScope (SB). ADR, polyp detection rate (PDR), mean adenomas per procedure (MAP), polyp characteristics and location, participant experience, procedural time and adverse events were measured. Comparison of ADR within the trial with national BowelScope ADR was also undertaken. RESULTS: 3222 participants were randomised (53% male) to receive EAB (n=1610) or SB (n=1612). Baseline demographics were comparable between arms. ADR in the EAB arm was 13.3% and that in the SB arm was 12.2% (p=0.353). No statistically significant differences were found in PDR, MAP, polyp characteristics or location, participant experience, complications or procedural characteristics. ADR in the SB control arm was 3.1% higher than the national ADR. CONCLUSION: EV did not improve BowelScope ADR when compared with SB. ADR in both arms was higher than the national ADR. Where detection rates are already high, EV is unable to improve detection further. TRIAL REGISTRATION NUMBERS: NCT03072472, ISRCTN30005319 and CPMS ID 33224.

Standalone performance of artificial intelligence for upper GI neoplasia: a meta-analysis.

OBJECTIVE: Artificial intelligence (AI) may reduce underdiagnosed or overlooked upper GI (UGI) neoplastic and preneoplastic conditions, due to subtle appearance and low disease prevalence. Only disease-specific AI performances have been reported, generating uncertainty on its clinical value. DESIGN: We searched PubMed, Embase and Scopus until July 2020, for studies on the diagnostic performance of AI in detection and characterisation of UGI lesions. Primary outcomes were pooled diagnostic accuracy, sensitivity and specificity of AI. Secondary outcomes were pooled positive (PPV) and negative (NPV) predictive values. We calculated pooled proportion rates (%), designed summary receiving operating characteristic curves with respective area under the curves (AUCs) and performed metaregression and sensitivity analysis. RESULTS: Overall, 19 studies on detection of oesophageal squamous cell neoplasia (ESCN) or Barrett's esophagus-related neoplasia (BERN) or gastric adenocarcinoma (GCA) were included with 218, 445, 453 patients and 7976, 2340, 13 562 images, respectively. AI-sensitivity/specificity/PPV/NPV/positive likelihood ratio/negative likelihood ratio for UGI neoplasia detection were 90% (CI 85% to 94%)/89% (CI 85% to 92%)/87% (CI 83% to 91%)/91% (CI 87% to 94%)/8.2 (CI 5.7 to 11.7)/0.111 (CI 0.071 to 0.175), respectively, with an overall AUC of 0.95 (CI 0.93 to 0.97). No difference in AI performance across ESCN, BERN and GCA was found, AUC being 0.94 (CI 0.52 to 0.99), 0.96 (CI 0.95 to 0.98), 0.93 (CI 0.83 to 0.99), respectively. Overall, study quality was low, with high risk of selection bias. No significant publication bias was found. CONCLUSION: We found a high overall AI accuracy for the diagnosis of any neoplastic lesion of the UGI tract that was independent of the underlying condition. This may be expected to substantially reduce the miss rate of precancerous lesions and early cancer when implemented in clinical practice.

Acute sedation-associated complications in GI endoscopy (ProSed 2 Study): results from the prospective multicentre electronic registry of sedation-associated complications.

OBJECTIVES: Sedation has been established for GI endoscopic procedures in most countries, but it is also associated with an added risk of complications. Reported complication rates are variable due to different study methodologies and often limited sample size. DESIGNS: Acute sedation-associated complications were prospectively recorded in an electronic endoscopy documentation in 39 study centres between December 2011 and August 2014 (median inclusion period 24 months). The sedation regimen was decided by each study centre. RESULTS: A total of 368 206 endoscopies was recorded; 11% without sedation. Propofol was the dominant drug used (62% only, 22.5% in combination with midazolam). Of the sedated patients, 38 (0.01%) suffered a major complication, and overall mortality was 0.005% (n=15); minor complications occurred in 0.3%. Multivariate analysis showed the following independent risk factors for all complications: American Society of Anesthesiologists class >2 (OR 2.29) and type and duration of endoscopy. Of the sedation regimens, propofol monosedation had the lowest rate (OR 0.75) compared with midazolam (reference) and combinations (OR 1.0-1.5). Compared with primary care hospitals, tertiary referral centres had higher complication rates (OR 1.61). Notably, compared with sedation by a two-person endoscopy team (endoscopist/assistant; 53.5% of all procedures), adding another person for sedation (nurse, physician) was associated with higher complication rates (ORs 1.40-4.46), probably due to higher complexity of procedures not evident in the multivariate analysis. CONCLUSIONS: This large multicentre registry study confirmed that severe acute sedation-related complications are rare during GI endoscopy with a very low mortality. The data are useful for planning risk factor-adapted sedation management to further prevent sedation-associated complications in selected patients. TRIAL REGISTRATION NUMBER: DRKS00007768; Pre-results.