Electrosurgical generators

Cold versus hot snare endoscopic mucosal resection for large (≥15 mm) flat non-pedunculated colorectal polyps: a randomised controlled trial

BACKGROUND AND AIMS

Conventional hot snare endoscopic mucosal resection (H-EMR) is effective for the management of large (≥20 mm) non-pedunculated colon polyps (LNPCPs) however, electrocautery-related complications may incur significant morbidity. With a superior safety profile, cold snare EMR (C-EMR) of LNPCPs is an attractive alternative however evidence is lacking. We conducted a randomised trial to compare the efficacy and safety of C-EMR to H-EMR.

METHODS

Flat, 15-50 mm adenomatous LNPCPs were prospectively enrolled and randomly assigned to C-EMR or H-EMR with margin thermal ablation at a single tertiary centre. The primary outcome was endoscopically visible and/or histologically confirmed recurrence at 6 months surveillance colonoscopy. Secondary outcomes were clinically significant post-EMR bleeding (CSPEB), delayed perforation and technical success.

RESULTS

177 LNPCPs in 177 patients were randomised to C-EMR arm (n=87) or H-EMR (n=90). Treatment groups were equivalent for technical success 86/87 (98.9%) C-EMR versus H-EMR 90/90 (100%); p=0.31. Recurrence was significantly greater in C-EMR (16/87, 18.4% vs 1/90, 1.1%; relative risk (RR) 16.6, 95% CI 2.24 to 122; p<0.001).Delayed perforation (1/90 (1.1%) vs 0; p=0.32) only occurred in the H-EMR group. CSPEB was significantly greater in the H-EMR arm (7/90 (7.8%) vs 1/87 (1.1%); RR 6.77, 95% CI 0.85 to 53.9; p=0.034).

CONCLUSION

Compared with H-EMR, C-EMR for flat, adenomatous LNPCPs, demonstrates superior safety with equivalent technical success. However, endoscopic recurrence is significantly greater for cold snare resection and is currently a limitation of the technique.

TRIAL REGISTRATION NUMBER

NCT04138030.

HOT VERSUS COLD SNARE FOR COLORECTAL POLYPECTOMIES SIZED UP TO 10MM: A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

BACKGROUND

Colorectal cancer is the third most common cancer, and prevention relies on screening programs with resection complete resection of neoplastic lesions.

OBJECTIVE

We aimed to evaluate the best snare polypectomy technique for colorectal lesions up to 10 mm, focusing on complete resection rate, and adverse events.

METHODS

A comprehensive search using electronic databases was conducted to identify randomized controlled trials comparing hot versus cold snare resection for polyps sized up to 10 mm, and following PRISMA guidelines, a meta-analysis was performed. Outcomes included complete resection rate, en bloc resection rate, polypectomy, procedure times, immediate, delayed bleeding, and perforation.

RESULTS

Nineteen RCTs involving 8720 patients and 17588 polyps were included. Hot snare polypectomy showed a higher complete resection rate (RD, 0.02; 95%CI [+0.00,0.04]; P=0.03; I 2=63%), but also a higher rate of delayed bleeding (RD 0.00; 95%CI [0.00, 0.01]; P=0.01; I 2=0%), and severe delayed bleeding (RD 0.00; 95%CI [0.00, 0.00]; P=0.04; I 2=0%). Cold Snare was associated with shorter polypectomy time (MD -46.89 seconds; 95%CI [-62.99, -30.79]; P<0.00001; I 2=90%) and shorter total colonoscopy time (MD -7.17 minutes; 95%CI [-9.10, -5.25]; P<0.00001; I 2=41%). No significant differences were observed in en bloc resection rate or immediate bleeding.

CONCLUSION

Hot snare polypectomy presents a slightly higher complete resection rate, but, as it is associated with a longer procedure time and a higher rate of delayed bleeding compared to Cold Snare, it cannot be recommended as the gold standard approach. Individual analysis and personal experience should be considered when selecting the best approach.

Novel quantitative assessment indicators for efficiency and precision of endoscopic submucosal dissection in animal training models by analyzing an electrical surgical unit

OBJECTIVES

Although endoscopic submucosal dissection (ESD) training is important, quantitative assessments have not been established. This study aimed to explore a novel quantitative assessment system by analyzing an electrical surgical unit (ESU).

METHODS

This was an ex vivo study. Step one: to identify the novel efficiency indicators, 20 endoscopists performed one ESD each, and we analyzed correlations between their resection speed and electrical status. Step two: to identify the novel precision indicators, three experts and three novices performed one ESD each, and we compared the stability of the electrical status. Step three: three novices in step two performed 19 additional ESDs, and we analyzed the learning curve using novel indicators.

RESULTS

Step one: the percentage of total activation time (AT) of ESU in the procedure time (β coefficient, 0.80; P < 0.01) and AT required for submucosal dissection (β coefficient, -0.57; P < 0.01) were significantly correlated with the resection speed. Step two: coefficient of variation of the AT per one pulse (0.16 [range, 0.13-0.17] vs. 0.26 [range, 0.20-0.41], P = 0.049) and coefficient of variation of the peak electric power per pulse during mucosal incision (0.14 [range, 0.080-0.15] vs. 0.25 [range, 0.24-0.28], P = 0.049) were significantly lower in the experts than in the novices. Regarding the learning curve, the percentage of total AT of ESU in the procedure time and AT required for submucosal dissection had a trend of improvement.

CONCLUSION

Novel indicators identified by analyzing ESU enable quantitative assessment for endoscopist's skill.

New Medical Device and Therapeutic Approvals in Otolaryngology: State of the Art Review of 2022

Objective

To review new drugs and devices relevant to otolaryngology approved by the Food and Drug Administration (FDA) in 2022.

Data Sources

Publicly available FDA data on drugs and devices approved in 2022.

Review Methods

A preliminary screen was conducted to identify drugs and devices relevant to otolaryngology. A secondary screen by members of the American Academy of Otolaryngology-Head and Neck Surgery's (AAO-HNS) Medical Devices and Drugs Committee differentiated between minor updates and new approvals. The final list of drugs and devices was sent to members of each subspecialty for review and analysis.

Conclusion

A total of 1251 devices and 37 drugs were identified on preliminary screening. Of these, 329 devices and 5 drugs were sent to subspecialists for further review, from which 37 devices and 2 novel drugs were selected for further analysis. The newly approved devices spanned all subspecialties within otolaryngology. Many of the newly approved devices aimed to enhance patient experience, including over-the-counter hearing aids, sleep monitoring devices, and refined CPAP devices. Other advances aimed to improve surgical access, convenience, or comfort in the operating room and clinic.

Implications for Practice

Many new devices and drugs are approved each year to improve patient care and care delivery. By staying up to date with these advances, otolaryngologists can leverage new innovations to improve the safety and quality of care. Given the recent approval of these devices, further studies are needed to assess long-term impact within the field of otolaryngology.

Endoscopic management of colorectal polyps

Colorectal polyps are premalignant lesions in the lower gastrointestinal tract. Endoscopic polypectomy is an effective strategy to prevent colorectal cancer morbidity and more invasive procedures. Techniques for the endoscopic resection of polyps keep evolving, and endoscopists are required to perform the most appropriate technique for each polyp. In this review, we outline the evaluation and classification of polyps, update the recommendations for optimal treatment, describe the polypectomy procedures and their strengths/weaknesses, and discuss the promising innovative methods or concepts.

AGA Clinical Practice Update on Gastric Peroral Endoscopic Myotomy for Gastroparesis: Commentary

DESCRIPTION

The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) is to review the available evidence and provide expert advice regarding cognitive, procedural, and post-procedural aspects of performing gastric peroral endoscopic myotomy for the treatment of refractory gastroparesis.

METHODS

This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This expert commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors who are advanced endoscopists with expertise in treating patients by performing third-space endoscopy and gastric peroral endoscopic myotomy.

Use of lasers in gastrointestinal endoscopy: a review of the literature

Lasers emit highly directional light with consistent wavelengths, and recent studies have demonstrated their successful applications in gastrointestinal endoscopic therapy. Although argon plasma coagulators (APC) became the preferred treatment option due to improved safety profile and lower costs, advancements in laser and optic fiber manufacturing have reignited interest in laser treatment. Different laser wavelengths have distinct features and applications based on their tissue absorption coefficient. Lasers with shorter wavelengths are effectively absorbed by hemoglobin, resulting in a good coagulation effect. Near-infrared lasers have ability to ablate solid tumors, while far-infrared lasers can make precise mucosal incisions without causing peripheral thermal damage. Lasers have proven to be highly applicable to endoscopy devices such as endoscopes, endoscopic ultrasound (EUS), double-balloon enteroscopes (DBE), and endoscopic retrograde cholangiopancreatography (ERCP), making them a potent tool to enhance the effectiveness of endoscopic treatments with minimal adverse events. This review aims to help readers understand the applications and effectiveness of lasers in gastrointestinal endoscopy, with the potential to promote the development and application of laser technology in the medical field.

Esophageal Dilation in Children: A State of the Art Review

Esophageal dilations in children are performed by several pediatric and adult professionals. We aim to summarize improvements in safety and new technology used for the treatment of complex and refractory strictures, including triamcinolone injection, endoscopic electro-incisional therapy, topical mitomycin-C application, stent placement, functional lumen imaging probe assisted dilation, and endoscopic vacuum-assisted closure in the pediatric population.

Understanding the Principles of Electrosurgery for Endoscopic Surgery and Third Space Endoscopy

Electrosurgery is the application of high-frequency electrical alternating current to biologic tissue to cut, coagulate, desiccate, and/or fulgurate. Electrosurgery is commonly used in gastrointestinal endoscopy, with applications including biliary sphincterotomy, polypectomy, hemostasis, the ablation of lesions, and endoscopic surgery. Understanding electrosurgical principles is important in endoscopic surgery to achieve the desired therapeutic effect, optimize procedural outcomes, and minimize risks or adverse events. This article describes fundamental principles that apply to electrosurgical units, operator technique, and practical considerations for achieving desired tissue effects in endoscopic surgery; and provides practical guidance and safety considerations when using electrosurgical units in endoscopic surgery.

Histopathological effects of electrosurgical interventions in an in vivo porcine model of colonic endoscopic mucosal resection

OBJECTIVE

Endoscopic mucosal resection (EMR) in the colon has been widely adopted, but there is limited data on the histopathological effects of the differing electrosurgical currents (ESCs) used. We used an in vivo porcine model to compare the tissue effects of ESCs for snare resection and adjuvant margin ablation techniques.

DESIGN

Standardised EMR was performed by a single endoscopist in 12 pigs. Two intersecting 15 mm snare resections were performed. Resections were randomised 1:1 using either a microprocessor-controlled current (MCC) or low-power coagulating current (LPCC). The lateral margins of each defect were treated with either argon plasma coagulation (APC) or snare tip soft coagulation (STSC). Colons were surgically removed at 72 hours. Two specialist pathologists blinded to the intervention assessed the specimens.

RESULTS

88 defects were analysed (median 7 per pig, median defect size 29×17 mm). For snare ESC effects, 156 tissue sections were assessed. LPCC was comparable to MCC for deep involvement of the colon wall. For margin ablation, 172 tissue sections were assessed. APC was comparable to STSC for deep involvement of the colon wall. Islands of preserved mucosa at the coagulated margin were more likely with APC compared with STSC (16% vs 5%, p=0.010).

CONCLUSION

For snare resection, MCC and LPCC did not produce significantly different tissue effects. The submucosal injectate may protect the underlying tissue, and technique may more strongly dictate the depth and extent of final injury. For margin ablation, APC was less uniform and complete compared with STSC.

[Not Available]

Objectives and study aims  Recent pilot studies have assessed the feasibility of a novel 1.9-/1.5-μm dual emission endoscopic laser treatment ( _1.9-/1.5-μm DEELT) for endoscopic hemostasis, ablation and resection. In this study, we investigated the safety and efficacy of _1.9-/1.5-μm DEELT in patients with chronic anemia due to gastrointestinal vascular lesions in a real-life multicenter cohort setting.

Patients and methods  Consecutive patients with moderate/severe iron-deficiency anemia undergoing _1.9-/1.5-μm DEELT for upper and lower gastrointestinal bleeding due to vascular lesions were enrolled in three academic referral centers. Safety and successful ablation of vascular lesions were the primary outcomes. Long-term hemoglobin level, blood transfusion requirements, endoscopic severity scores of complex vascular disorders and technical lasing parameters were also assessed. Long-term hemoglobin variations have been further assessed, with repeated measure analysis of variance and univariate analyses.

Results  Fifty patients (median age 74; range 47 to 91 years) with gastric antral vascular ectasia (GAVE) (22), angioectasia (22) and radiation proctopathy (6) underwent 58 _1.9-/1.5-μm DEELT between 2016 and 2020. All procedures were technically feasible leading to successful ablation of the targeted lesion/s, with no incident or adverse event potentially related to the _1.9-/1.5-μm DEELT technique. Within a 6-month follow-up, hemoglobin values significantly rose (+ 1.77 at 1 month and + 1.70 g/dL at 6 months, P  < 0.01), the blood supply requirement decreased (at least one transfusion in 32 versus 13 patients, P  < 0.01), and GAVE lesions showed a clear endoscopic improvement (from 5 points to 1 points, P  < 0.01).

Conclusions  The 1.9-/1.5-μm laser system is a safe and effective endoscopic tool for haemostatic ablation of bleeding vascular lesions within the gastrointestinal tract in tertiary referral centers.

Education and gastroenterology fellow knowledge about endoscopic mucosal resection of colon adenomas: a survey-based study

Background and study aims  Endoscopic mucosal resection (EMR) is an effective way to remove large (> 2 cm) colon adenomas. Training about it has not been standardized in fellowship programs. This study was aimed at evaluating the education and knowledge of gastroenterology fellows about EMR of colorectal adenomas. Methods  Participation in this survey was offered to 1730 gastroenterology fellows in the United States during the academic year 2019 to 2020. The survey assessed endoscopic mucosal resection training and knowledge and was approved and administered by the American College of Gastroenterology. Results  A total of 163 fellows (9.4 %) completed the survey. Only 85 fellows (52.1 %) reported receiving formal education in endoscopic mucosal resection. Fellow confidence was lowest regarding knowing electrosurgery unit settings. Fewer fellows correctly identified Paris 0-IIb (79, 48.5 %; P  < 0.0001) or NICE I (114, 69.9 %; P  < 0.01) lesions as compared to other Paris and NICE III lesions, respectively. Only 73 (44.8 %) and 93 fellows (57.1 %) arranged steps of EMR in the correct order and identified the correct type of current used for resection, respectively. Training year, male sex, and provision of advanced endoscopy rotations during fellowship were associated with a higher knowledge score for EMR. Conclusions  Nearly half of all fellows reported no formal education in EMR and incorrectly ordered its steps. Adenoma assessment by Paris and NICE classifications and electrosurgery unit settings were the most prominent knowledge deficiencies. Incorporation of standardized training about EMR with inclusion of advanced endoscopy rotations appears to be an important educational opportunity during gastroenterology fellowship.

Devices and techniques for flexible endoscopic management of Zenker's diverticulum (with videos)

BACKGROUND AND AIMS

Zenker's diverticulum (ZD) has traditionally been treated with open surgery or rigid endoscopy. With the advances in endoscopy, alternative flexible endoscopic treatments have been developed.

METHODS

This document reviews current endoscopic techniques and devices used to treat ZD.

RESULTS

The endoscopic techniques may be categorized as the traditional flexible endoscopic septal division and the more recent submucosal tunneling endoscopic septum division, also known as peroral endoscopic myotomy for ZD. This document also addresses clinical outcomes, safety, and financial considerations.

CONCLUSIONS

Flexible endoscopic approaches treat symptomatic ZD with results that are favorable compared with traditional open surgical or rigid endoscopic alternatives.

Endoscopic polypectomy devices

Video 1Use of submucosal injection prior to en-bloc endoscopic mucosal resection.Video 2Use of a detachable loop ligating device prior to hot snare resection of a pedunculated polyp.

Goff Septotomy Is a Safe and Effective Salvage Biliary Access Technique Following Failed Cannulation at ERCP

BACKGROUND

Biliary cannulation is readily achieved in > 85% of patients undergoing endoscopic retrograde cholangiopancreatography (ERCP). When standard cannulation techniques fail, salvage techniques utilized include the needle knife precut, double wire technique, and Goff septotomy.

METHODS

Records of patients undergoing ERCP from 2005 to 2016 were retrospectively examined using a prospectively maintained endoscopy database. Patients requiring salvage techniques for biliary access were analyzed together with a control sample of 20 randomly selected index ERCPs per study year. Demographic and clinical variables including indications for ERCP, cannulation rates, and adverse events were collected.

RESULTS

A total of 7984 patients underwent ERCP from 2005 to 2016. Biliary cannulation was successful in 94.9% of control index ERCPs, 87.2% of patients who underwent Goff septotomy (significantly higher than for all other salvage techniques, p ≤ 0.001), 74.5% of patients in the double wire group and 69.6% of patients in the needle knife precut group. Adverse event rates were similar in the Goff septotomy (4.1%) and index ERCP control sample (2.7%) groups. Adverse events were significantly higher in the needle knife group (27.2%) compared with all other groups.

CONCLUSIONS

This study represents the largest study to date of Goff septotomy as a salvage biliary access technique. It confirms the efficacy of Goff septotomy and indicates a safety profile similar to standard cannulation techniques and superior to the widely employed needle knife precut sphincterotomy. Our safety and efficacy data suggest that Goff septotomy should be considered as the primary salvage approach for failed cannulation, with needle knife sphincterotomy restricted to Goff septotomy failures.

Devices and techniques for endoscopic treatment of residual and fibrotic colorectal polyps (with videos)

BACKGROUND AND AIMS

Residual neoplasia after macroscopically complete EMR of large colon polyps has been reported in 10% to 32% of resections. Often, residual polyps at the site of prior polypectomy are fibrotic and nonlifting, making additional resection challenging.

METHODS

This document reviews devices and methods for the endoscopic treatment of fibrotic and/or residual polyps. In addition, techniques reported to reduce the incidence of residual neoplasia after endoscopic resection are discussed.

RESULTS

Descriptions of technologies and available outcomes data are summarized for argon plasma coagulation ablation, snare-tip coagulation, avulsion techniques, grasp-and-snare technique, EndoRotor endoscopic resection system, endoscopic full-thickness resection device, and salvage endoscopic submucosal dissection.

CONCLUSIONS

Several technologies and techniques discussed in this document may aid in the prevention and/or resection of fibrotic and nonlifting polyps.

Effects of Blended (Yellow) vs Forced Coagulation (Blue) Currents on Adverse Events, Complete Resection, or Polyp Recurrence After Polypectomy in a Large Randomized Trial

BACKGROUND & AIMS

There is debate over the type of electrosurgical setting that should be used for polyp resection. Some endoscopists use a type of blended current (yellow), whereas others prefer coagulation (blue). We performed a single-blinded, randomized trial to determine whether type of electrosurgical setting affects risk of adverse events or recurrence.

METHODS

Patients undergoing endoscopic mucosal resection of nonpedunculated colorectal polyps 20 mm or larger (n = 928) were randomly assigned, in a 2 × 2 design, to groups that received clip closure or no clip closure of the resection defect (primary intervention) and then to either a blended current (Endocut Q) or coagulation current (forced coagulation) (Erbe Inc) (secondary intervention and focus of the study). The study was performed at multiple centers, from April 2013 through October 2017. Patients were evaluated 30 days after the procedure (n = 919), and 675 patients underwent a surveillance colonoscopy at a median of 6 months after the procedure. The primary outcome was any severe adverse event in a per patient analysis. Secondary outcomes were complete resection and recurrence at first surveillance colonoscopy in a per polyp analysis.

RESULTS

Serious adverse events occurred in 7.2% of patients in the Endocut group and 7.9% of patients in the forced coagulation group, with no significant differences in the occurrence of types of events. There were no significant differences between groups in proportions of polyps that were completely removed (96% in the Endocut group vs 95% in the forced coagulation group) or the proportion of polyps found to have recurred at surveillance colonoscopy (17% and 17%, respectively). Procedural characteristics were comparable, except that 17% of patients in the Endocut group had immediate bleeding that required an intervention, compared with 11% in the forced coagulation group (P = .006).

CONCLUSIONS

In a randomized trial to compare 2 commonly used electrosurgical settings for the resection of large colorectal polyps (Endocut vs forced coagulation), we found no difference in risk of serious adverse events, complete resection rate, or polyp recurrence. Electrosurgical settings can therefore be selected based on endoscopist expertise and preference. Clinicaltrials.gov ID NCT01936948.

Pediatric Colonoscopic Polypectomy Technique

Colonoscopy with polypectomy is frequently performed in pediatric patients based on symptoms, with the majority of polyps identified being benign juvenile pedunculated polyps with a vascular stalk. This is in distinction to adults where polypectomy is often performed as part of a colon cancer screening and prevention strategy and a higher fraction of polyps are sessile and or dysplastic. In adults, polypectomy techniques emphasize a need for deeper resection to ensure complete resection of adenomas or potential carcinoma in situ. Adenomatous polyps can occur in the pediatric age group and may be associated with an underlying polyposis, hereditary or chronic inflammatory conditions. Polypectomy techniques include use of cold biopsy forceps for very small polyps, cold snare polypectomy for small sessile polyps and hot snare polypectomy for the majority of polyps in the pediatric age group. Adjuvant techniques include epinephrine volume reduction, saline-assisted polypectomy and hemostatic techniques including injection, clip application and loop application to prevent or treat post-polypectomy bleeding. Electrosurgical principles guide the settings and type of current utilized during hot snare polypectomy. Polypectomy utilizing thermal techniques is associated with a higher risk of complications compared with diagnostic colonoscopy.

Impact of electrical pulse cut mode during endoscopic papillectomy: Pilot randomized clinical trial

OBJECTIVE

Endoscopic papillectomy is increasingly being used for ampullary adenoma treatment. However, it remains challenging despite increased safety with treatment advances. The ideal power output and electrosurgical current mode for mucosal resection are not established. We aimed to identify the ideal electrical pulse for use during resection.

METHODS

This pilot randomized, single-blind, prospective, multicenter trial, recruited patients with ampullary adenomas and conventional anatomy who were scheduled to undergo endoscopic papillectomy. Endoscopic treatment was performed using a standardized algorithm and patients were randomized for endoscopic papillectomy with Endocut or Autocut. The primary outcome was the incidence of delayed bleeding. Incidence of procedure-related pancreatitis, successful complete resection, pathological findings, and other adverse events were secondary endpoints.

RESULTS

Sixty patients were enrolled over a 2-year period. The incidences of delayed bleeding (13.3% vs. 16.7%, P = 1.00) and pancreatitis (27% vs. 30%, P = 0.77) were similar between both groups. The rate of crush artifacts was higher in the Endocut than in the Autocut group (27% vs. 3.3%, P = 0.03). Immediate bleeding when resecting tumors greater than 14 mm in diameter was more common in the Autocut than in the Endocut group (88% vs. 46%, P = 0.04).

CONCLUSIONS

The Autocut and Endocut modes have similar efficacy and safety for endoscopic papillectomy. The Endocut mode may prevent immediate bleeding in cases with large tumor sizes, although it causes more frequent crush artifacts.

REGISTRY AND THE REGISTRATION NUMBER

The Japanese UMIN Clinical Trials Registry (UMIN-CTR: 000021382).

Use of electrosurgical units in the endoscopic resection of gastrointestinal tumors

Electrosurgical units (ESUs) are indispensable devices in our endoscopy units. However, many endoscopists are not well-trained on their use and their physical bases are usually not properly studied or understood. In addition, comparative data concerning the settings that may be applied in different circumstances are scarce in the medical literature. Given that it is important to be aware of their strengths and risks, we conducted a review of the available information and research on this topic.

Devices for endoscopic hemostasis of nonvariceal GI bleeding (with videos)

Background

Endoscopic intervention is often the first line of therapy for GI nonvariceal bleeding. Although some of the devices and techniques used for this purpose have been well studied, others are relatively new, with few available outcomes data.

Methods

In this document, we review devices and techniques for endoscopic treatment of nonvariceal GI bleeding, the evidence regarding their efficacy and safety, and financial considerations for their use.

Results

Devices used for endoscopic hemostasis in the GI tract can be classified into injection devices (needles), thermal devices (multipolar/bipolar probes, hemostatic forceps, heater probe, argon plasma coagulation, radiofrequency ablation, and cryotherapy), mechanical devices (clips, suturing devices, banding devices, stents), and topical devices (hemostatic sprays).

Conclusions

Endoscopic evaluation and treatment remains a cornerstone in the management of nonvariceal upper- and lower-GI bleeding. A variety of devices is available for hemostasis of bleeding lesions in the GI tract. Other than injection therapy, which should not be used as monotherapy, there are few compelling data that strongly favor any one device over another. For endoscopists, the choice of a hemostatic device should depend on the type and location of the bleeding lesion, the availability of equipment and expertise, and the cost of the device.

National survey of UK endoscopists showing variation in diathermy practice for colonic polypectomy

INTRODUCTION

Diathermy practice in colonic polypectomy has a poor evidence base. We surveyed endoscopists across the UK to gain an insight in current diathermy practice.

METHODS

An eight-question survey was designed to be compact, easy to complete, while still capturing the relevant data. This national survey was circulated by the endoscopy committees of the British Society of Gastroenterology and Association of Coloproctology of Great Britain and Ireland.

RESULTS

The survey was open between February and October 2016. Analysis showed: (1) 250/348 (71.8%) completed the full survey, 159 gastroenterologists (63.6%), 36 surgeons (14.4%), 34 gastroenterology trainees (13.6%), 21 others (8.4%); (2) predominant use of coagulation current for small pedunculated polypectomy, high rates of cold snare polypectomy for small sessile polyps (right 43.2% > left 34.4%); (3) a combination of coagulation and cutting current, or Endo Cut, was most popular for larger polypectomy; (4) low use of Endo Cut mode irrespective of size/location of polyp (17.2%-32.0%); (5) 204/250 (81.6%) used reduced current settings for right colon polypectomy; and (6) 208/250 (83.2%) were confident on knowledge and use of diathermy.

CONCLUSION

This national survey exposes a wide variation in practice suggesting that colonoscopists employ diathermy modalities that they are comfortable with. As many complications are as direct result of thermal injury and polypectomy is the most frequent therapeutic intervention, appropriate training and formal guidance is lacking.

A retrospective comparative study of argon plasma versus polypectome snare tip coagulation: effect on recurrence rate after resection of large laterally spreading type lesions

Background

Endoscopic mucosal resection (EMR) is an established technique for treating large laterally spreading type (LST) lesions ≥20 mm. The aim of our study was to compare the use of argon plasma (APC) versus snare-tip coagulation on the recurrence rate of large LST lesions.

Methods

All patients with large LST lesions resected by EMR between January 2006 and December 2014 were enrolled. After piecemeal resection, patients underwent either APC or snare-tip coagulation of the rim of the resection area and any residual adenomatous tissue. Follow up included colonoscopy and biopsies. Medical records, including characteristics of patients and polyps, complications and recurrence were retrieved and collected.

Results

One hundred one patients were included in the final analysis. They were divided into the APC group (n=50) and the snare-tip coagulation group (n=51). The 2 groups were similar concerning patients’ characteristics, size of polyps and histology. Post-polypectomy coagulation syndrome was observed in 8 patients (7.9%) (APC group: n=5 and snare tip group: n=3). EMR-related bleeding occurred in 9 patients (8.9%) (APC group: n=4 and snare tip group: n=5). Total recurrence rate was 14.85% (16% and 13.7% in APC and snare-tip groups, respectively, P=0.34).

Conclusion

The effectiveness of snare-tip coagulation is comparable with that of APC with respect to recurrence rate after resection of large LST lesions. It thus represents a cost-effective alternative to APC.

Basic training in digestive endoscopy for resident physicians in gastroenterology. Recommendations by the Sociedad Española de Endoscopia Digestiva (SEED)

Digestive endoscopy is the most effective tool available for the diagnosis of multiple gastrointestinal (GI) tract conditions, and it represents a key aspect in the training of gastroenterology residents according to the Spanish MIR (médico interno residente) program. The Sociedad Española de Endoscopia Digestiva (SEED), aware of all the technical advances that have emerged during the past few years, deems it necessary to define a program of the skills specialists-in-training in gastroenterology should acquire during their residency. This paper describes the goals of endoscopy training, the techniques that should be mastered, and the diagnostic and therapeutic skills this specialty requires. Finally, a model is suggested for the assessment of competence.

Comparison of the Thermal Spread of Three Different Electrosurgical Generators on Rat Uterus: A Preliminary Experimental Study

BACKGROUND/AIMS

The objective of this study was to compare the depth and width of thermal spread caused on rat uterine tissue after application of 3 different electrosurgical generators.

METHODS

Alsa Excell 350 MCDSe (Unit A), Meditom DT-400P (Unit M), and ERBE Erbotom VIO 300 D (Unit E) electrosurgical units (ESUs) were used. The number of Wistar Hannover rats required to obtain valid results was 10. The primary objective of the study was to compare the 3 ESUs using the same instrument and the same waveform. The secondary objective of the study was to compare the differences between monopolar and bipolar systems of each ESU separately using the same waveform.

RESULTS

The thermal spread caused by each ESU using monopolar instruments with continuous and interrupted waveforms was significantly different. Among the 3 devices, Unit A caused the largest thermal uterine tissue spread. On the other hand, Unit E caused the most superficial thermal tissue spread, and the smallest thermal spread among all ESUs.

CONCLUSIONS

Surgeons should note that different ESUs used with the same power output might create different thermal effects especially in the monopolar configuration within the same waveform, for the same duration, and with the same instrument.

The characterization of surgical smoke from various tissues and its implications for occupational safety

Electrosurgery produces surgical smoke. Different tissues produce different quantities and types of smoke, so we studied the particle characteristics of this surgical smoke in order to analyze the implications for the occupational health of the operation room personnel. We estimated the deposition of particulate matter (PM) from surgical smoke on the respiratory tract of operation room personnel using clinically relevant tissues from Finnish landrace porcine tissues including skeletal muscle, liver, subcutaneous fat, renal pelvis, renal cortex, lung, bronchus, cerebral gray and white matter, and skin. In order to standardize the electrosurgical cuts and smoke concentrations, we built a customized computer-controlled platform. The smoke particles were analyzed with an electrical low pressure impactor (ELPI), which measures the concentration and aerodynamic size distribution of particles with a diameter between 7 nm and 10 μm. There were significant differences in the mass concentration and size distribution of the surgical smoke particles depending on the electrocauterized tissue. Of the various tissues tested, liver yielded the highest number of particles. In order to better estimate the health hazard, we propose that the tissues can be divided into three distinct classes according to their surgical smoke production: 1) high-PM tissue for liver; 2) medium-PM tissues for renal cortex, renal pelvis, and skeletal muscle; and 3) low-PM tissues for skin, gray matter, white matter, bronchus, and subcutaneous fat.

Clinical guidelines for endoscopic mucosal resection of non-pedunculated colorectal lesions

This document summarizes the contents of the Clinical Guidelines for the Endoscopic Mucosal Resection of Non-Pedunculated Colorectal Lesions that was developed by the working group of the Spanish Society of Digestive Endoscopy (GSEED of Endoscopic Resection). This document presents recommendations for the endoscopic management of superficial colorectal neoplastic lesions.

Japan Gastroenterological Endoscopy Society guidelines for endoscopic sphincterotomy

The Japan Gastroenterological Endoscopy Society (JGES) has recently compiled guidelines for endoscopic sphincterotomy (EST) using evidence-based methods. Content regarding actual clinical practice, including detailed endoscopic procedures, instruments, device types and usage, has already been published by the JGES postgraduate education committee in May 2015 and, thus, in these guidelines we avoided duplicating such content as much as possible. The guidelines do not address pancreatic sphincterotomy, endoscopic papillary balloon dilation (EPBD), and endoscopic papillary large balloon dilation (EPLBD). The guidelines for EPLBD are planned to be developed separately. The evidence level in this field is often low and, in many instances, strong recommendation has to be determined on the basis of expert consensus. At this point in time, the guidelines are divided into six items including indications, techniques, specific cases, adverse events, outcomes, and postoperative follow up.

Radiofrequency perforation of the pulmonary valve: an efficient low cost solution

Objective The aim of the study was to assess the feasibility of using commonly available catheterization laboratory equipment for radiofrequency perforation of the pulmonary valve in patients with pulmonary atresia and intact ventricular septum. Methods The system (off-label use for all items) is made up of a co-axial telescopic arrangement consisting of a 0.014" PT 2 ™ coronary guidewire, for insulation inside a 2.7-F microcatheter which has an inner lumen of 0.021". The microcatheter was passed via a standard 4-F right coronary catheter to just below the atretic pulmonary valve. Radiofrequency (RF) energy was delivered using a standard electrosurgical system. In vitro testing had been performed and indicated that 5-10 W for 2-5 s would be sufficient for valve perforation. Results Radiofrequency perforation was successfully performed in all (n = 5, 100%) patients at a median age of 3 days (range: 1-36) and weight 2.7 kg (range 2.3-3.0). In one patient the pericardium was entered during the initial attempt; the generator was put on coagulation mode during retrieval of the guidewire and no haemopericardium occurred. The pulmonary valve was dilated in all; in three patients (n = 3) the ductus arteriosus was stented during the same session. Conclusion Results of the study show that it is feasible to perforate the pulmonary valve safely using this system. Availability, simplicity and cost are noteworthy benefits.

Ex vivo experimental study on the Thulium laser system: new horizons for interventional endoscopy (with videos)

BACKGROUND AND STUDY AIMS

 The Thulium laser system (TLS) is an emerging interventional tool adopted in many surgical specialties. Its 2.0-μm wavelength allows precise coagulation (0.2 - 0.4 mm in depth) and cutting, limiting the possibilities of collateral injuries. We tested the impact of the TLS for gastric endoscopic submucosal dissection (ESD) and per oral endoscopic myotomy (POEM) ex vivo in pigs.

MATERIALS AND METHODS

  Ex vivo porcine stomach and esophagus models underwent 2 POEMs, and 3 ESDs (mean diameter 3.5 cm) with TLS using a 272-µm and a 365-µm thick optical fibers. Both continuous and pulsed laser emission were evaluated. Subsequent histopathological analysis was performed by an expert GI pathologist on the whole porcine models.

RESULTS

 Complete POEMs and gastric ESDs were successfully performed in all cases in 30 to 70 and 15 to 20 minutes. Both optical fibers were equally effective and precise. The best power output for mucosal incision was 25 to 30 W during ESD and 25 W for POEM using continuous laser emission. During submucosal dissection and tunneling the favorite power output was 20 W and 15 to 20 W, respectively, operating in continuous mode. No transmural perforation occurred throughout the operations and histopathology confirmed the absence of accidental muscular layer damage.

CONCLUSIONS

 The TLS stands out as a precise and manageable instrument in ex vivo models. This technique appears to be a promising tool for advanced interventional endoscopy.

The role of equipment in endoscopic complications

The role of the surrounding equipment in endoscopic complications has not been published widely. However, an adequate understanding of the advantages and disadvantages of such devices might be helpful to avoid unnecessary problems during endoscopy. This is an overview of the basic principles, benefits and possible harms of electrical power units, medical gases and vital sign monitoring equipment. The aim of this review is to summarize current knowledge about the approach to the electrosurgical unit settings; periprocedural precautions, minimizing the risk of interference between endoscopic equipment and other electrical devices; the appropriate selection of instruments regarding the electrosurgical outcome and the role of carbon dioxide, argon plasma coagulation, pulse oximetry and capnography.

Endoscopic submucosal dissection

ESD is an established effective treatment modality for premalignant and early-stage malignant lesions of the stomach, esophagus, and colorectum. Compared with EMR, ESD is generally associated with higher rates of en bloc, R0, and curative resections and a lower rate of local recurrence. Oncologic outcomes with ESD compare favorably with competing surgical interventions, and ESD also serves as an excellent T-staging tool to identify noncurative resections that will require further treatment. ESD is technically demanding and has a higher rate of adverse events than most endoscopic procedures including EMR. As such,sufficient training is critical to ensure safe conduct and high-quality resections. A standardized training model for Western endoscopists has not been clearly established,but will be self-directed and include courses, animal model training, and optimally an observership at an expert center.Numerous dedicated ESD devices are now available in the United States from different manufacturers. Although the use of ESD in the United States is increasing, issues related to technical difficulty, limited training opportunities and mentors, risk of adverse events, long procedure duration,and suboptimal reimbursement may limit ESD adoption in the United States to a modest number of academic referral centers for the foreseeable future.

Setting up the Pediatric Endoscopy Unit

As pediatric gastrointestinal endoscopy continues to develop and evolve, pediatric gastroenterologists are more frequently called on to develop and direct a pediatric endoscopy unit. Lack of published literature and focused training in fellowship can render decision making about design, capacity, operation, equipment purchasing, and staffing challenging. To help guide management decisions, we distributed a short survey to 18 pediatric gastroenterology centers throughout the United States and Canada. This article provides practical guidance by summarizing available expert opinions on the topic of setting up a pediatric endoscopy unit.

British Society of Gastroenterology/Association of Coloproctologists of Great Britain and Ireland guidelines for the management of large non-pedunculated colorectal polyps

These guidelines provide an evidence-based framework for the management of patients with large non-pedunculated colorectal polyps (LNPCPs), in addition to identifying key performance indicators (KPIs) that permit the audit of quality outcomes. These are areas not previously covered by British Society of Gastroenterology (BSG) Guidelines.A National Institute of Health and Care Excellence (NICE) compliant BSG guideline development process was used throughout and the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool was used to structure the guideline development process. A systematic review of literature was conducted for English language articles up to May 2014 concerning the assessment and management of LNPCPs. Quality of evaluated studies was assessed using the Scottish Intercollegiate Guidelines Network (SIGN) Methodology Checklist System. Proposed recommendation statements were evaluated by each member of the Guideline Development Group (GDG) on a scale from 1 (strongly agree) to 5 (strongly disagree) with >80% agreement required for consensus to be reached. Where consensus was not reached a modified Delphi process was used to re-evaluate and modify proposed statements until consensus was reached or the statement discarded. A round table meeting was subsequently held to finalise recommendations and to evaluate the strength of evidence discussed. The GRADE tool was used to assess the strength of evidence and strength of recommendation for finalised statements.KPIs, a training framework and potential research questions for the management of LNPCPs were also developed. It is hoped that these guidelines will improve the assessment and management of LNPCPs.

Cold Atmospheric Plasma: A Promising Complementary Therapy for Squamous Head and Neck Cancer

Head and neck squamous cell cancer (HNSCC) is the 7^th most common cancer worldwide. Despite the development of new therapeutic agents such as monoclonal antibodies, prognosis did not change for the last decades. Cold atmospheric plasma (CAP) presents the most promising new technology in cancer treatment. In this study the efficacy of a surface micro discharging (SMD) plasma device against two head and neck cancer cell lines was proved. Effects on the cell viability, DNA fragmentation and apoptosis induction were evaluated with the MTT assay, alkaline microgel electrophoresis (comet assay) and Annexin-V/PI staining. MTT assay revealed that the CAP treatment markedly decreases the cell viability for all tested treatment times (30, 60, 90, 120 and 180 s). IC 50 was reached within maximal 120 seconds of CAP treatment. Comet assay analysis showed a dose dependent high DNA fragmentation being one of the key players in anti-cancer activity of CAP. Annexin-V/PI staining revealed induction of apoptosis in CAP treated HNSCC cell lines but no significant dose dependency was seen. Thus, we confirmed that SMD Plasma technology is definitely a promising new approach on cancer treatment.

Improvement of Short-Term Outcomes for High-Risk Bleeding Peptic Ulcers With Addition of Argon Plasma Coagulation Following Endoscopic Injection Therapy: A Randomized Controlled Trial

A second endoscopic method together with injection therapy is recommended to treat high-risk bleeding peptic ulcers. This study investigated whether additional argon plasma coagulation (APC) treatment could influence hemostatic efficacy following endoscopic injection therapy to treat high-risk bleeding ulcers.From October 2010 to January 2012, eligible patients with high-risk bleeding ulcers were admitted to our hospital. They prospectively randomly underwent either APC therapy along with distilled water injection or distilled water injection alone. Episodes of rebleeding were retreated with endoscopic combination therapy. Patients in whom retreatment was ineffective underwent emergency surgery or transarterial embolization (TAE).A total of 116 enrolled patients were analyzed. The hemostatic efficacy in 58 patients treated with APC along with distilled water injection was compared with that in 58 patients treated with distilled water injection alone. The 2 treatment groups were similar with respect to all baseline characteristics. Initial hemostasis was accomplished in 56 patients treated with combined therapy, and 55 patients treated with distilled water injection therapy (97% vs 95%, P = 0.648). Bleeding recurred in 2 patients treated with combined therapy, and 9 patients treated with distilled water injection (3.6% vs 16%, P = 0.029). Treatment method was the only independent prognostic factor for recurrent bleeding (odds ratio 0.17; 95% confidence interval 0.03-0.84; P = 0.029). The 2 groups did not differ significantly in hospital stay, TAE, surgery, and mortality.Endoscopic therapy with APC following distilled water injection is more effective than distilled water injection alone for preventing rebleeding of peptic ulcer.

Endoscopic mucosal resection

EMR has become an established therapeutic option for premalignant and early-stage GI malignancies, particularly in the esophagus and colon. EMR can also aid in the diagnosis and therapy of subepithelial lesions localized to the muscularis mucosa or submucosa. Several dedicated EMR devices are available to facilitate these procedures. Adverse event rates, particularly bleeding and perforation, are higher after EMR relative to other basic endoscopic interventions but lower than adverse event rates for ESD. Endoscopists performing EMR should be knowledgeable and skilled in managing potential adverse events resulting from EMR.

Electrocautery Devices With Feedback Mode and Teflon-Coated Blades Create Less Surgical Smoke for a Quality Improvement in the Operating Theater

Monopolar electrocautery is a fast and elegant cutting option. However, as it creates surgical smoke containing polycyclic aromatic hydrocarbons (PAHs), it may be hazardous to the health of the surgical team. Although new technologies, such as feedback mode (FM) and Teflon-coated blades (TBs), reduce tissue damage, their impact on surgical smoke creation has not yet been elucidated. Therefore, we analyzed the plume at its source.The aim of this study was to evaluate if electrocautery FM and TBs create less surgical smoke.Porcine tissue containing skin was cut in a standardized manner using sharp-edged Teflon-coated blades (SETBs), normal-shaped TBs, or stainless steel blades (SSBs). Experiments were performed using FM and pure-cut mode. Surgical smoke was sucked through filters or adsorption tubes. Subsequently, filters were scanned and analyzed using a spectrophotometer. A high-performance liquid chromatography (HPLC-UV) was performed to detect benzo[a]pyrene (BaP) and phenanthrene as 2 of the most critical PAHs. Temperature changes at the cutting site were measured by an infrared thermometer.In FM, more surgical smoke was created using SSB compared with TBs (P < 0.001). Furthermore, differences between FM and pure-cut mode were found for SSB and TB (P < 0.001), but not for SETB (P = 0.911). Photometric analysis revealed differences in the peak heights of the PAH spectrum. In HLPC-UV, the amount of BaP and phenanthrene detected was lower for TB compared with SSB. Tissue temperature variations increased when SSB was used in FM and pure-cut mode. Furthermore, different modes revealed higher temperature variations with the use of SETB (P = 0.004) and TB (P = 0.005) during cutting, but not SSB (P = 0.789).We found that the use of both TBs and FM was associated with reduced amounts of surgical smoke created during cutting. Thus, the surgical team may benefit from the adoption of such new technologies, which could contribute to the primary prevention of smoke-related diseases.

Inducing valvular regurgitation in mice via thermal ablation of cardiac valves

This study presents early data in the development of a novel mouse model of heart failure utilizing thermal ablation on cardiac valves to induce valvular regurgitation. Thermal ablation of the valve was achieved through the application of radiofrequency (RF) electrical current. The objective was to apply enough energy to induce valve stiffening and retraction, which was hypothesized to produce valve insufficiency and blood regurgitation in vivo. Preliminary studies were performed to develop a workable energy delivery catheter that could be inserted through the carotid artery to the aortic valve. Catheter position between the aortic valve leaflets was verified by echocardiography. Valve function was evaluated before and after the thermal insult using Doppler measurements near the valve inflow and outflow, and early results demonstrate that the energy delivery catheter could successfully induce acute valve insufficiency. Further study is needed to refine the catheter to provide greater control over the degree of thermal damage and resulting changes in cardiac physiology.

Highlights from the 50th seminar of the korean society of gastrointestinal endoscopy

The July issue of Clinical Endoscopy deals with selected articles covering the state-of-the-art lectures delivered during the 50th seminar of the Korean Society of Gastrointestinal Endoscopy (KSGE) on March 30, 2014, highlighting educational contents pertaining to either diagnostic or therapeutic gastrointestinal (GI) endoscopy, which contain fundamental and essential points in GI endoscopy. KSGE is very proud of its seminar, which has been presented twice a year for the last 25 years, and hosted more than 3,500 participants at the current meeting. KSGE seminar is positioned as one of premier state-of-the-art seminars for endoscopy, covering topics for novice endoscopists and advanced experts, as well as diagnostic and therapeutic endoscopy. The 50th KSGE seminar consists of more than 20 sessions, including a single special lecture, concurrent sessions for GI endoscopy nurses, and sessions exploring new technologies. Nine articles were selected from these prestigious lectures, and invited for publication in this special issue. This introductory review, prepared by the editors of Clinical Endoscopy, highlights core contents divided into four sessions: upper GI tract, lower GI tract, pancreatobiliary system, and other specialized topic sessions, including live demonstrations and hands-on courses.

Electrosurgery: part I. Basics and principles

The term electrosurgery (also called radiofrequency surgery) refers to the passage of high-frequency alternating electrical current through the tissue in order to achieve a specific surgical effect. Although the mechanism behind electrosurgery is not completely understood, heat production and thermal tissue damage is responsible for at least the majority--if not all--of the tissue effects in electrosurgery. Adjacent to the active electrode, tissue resistance to the passage of current converts electrical energy to heat. The only variable that determines the final tissue effects of a current is the depth and the rate at which heat is produced. Electrocoagulation occurs when tissue is heated below the boiling point and undergoes thermal denaturation. An additional slow increase in temperature leads to vaporization of the water content in the coagulated tissue and tissue drying, a process called desiccation. A sudden increase in tissue temperature above the boiling point causes rapid explosive vaporization of the water content in the tissue adjacent to the electrode, which leads to tissue fragmentation and cutting.

Electrosurgery: part II. Technology, applications, and safety of electrosurgical devices

Electrosurgical currents can be delivered to tissue in monopolar or bipolar and monoterminal or biterminal modes, with the primary difference between these modes being their safety profiles. A monopolar electrosurgical circuit includes an active electrode and a dispersive (return) electrode, while there are 2 active electrodes in bipolar mode. In monoterminal mode, there is an active electrode, but there is no dispersive electrode connected to the patient's body and instead the earth acts as the return electrode. Biterminal mode uses a dispersive electrode connected to the patient's body, has a higher maximum power, and can be safer than monoterminal mode in certain situations. Electrosurgical units have different technologies for controlling the output power and for providing safety. A thorough understanding of these technologies helps with a better selection of the appropriate surgical generator and modes.