Efficacy of forced coagulation with low high-frequency power setting during endoscopic submucosal dissection

Electrosurgical unit in GI endoscopy: the proper settings for practice

INTRODUCTION

Electrosurgical unit (ESU) is integral to the endoscopy unit. The proper knowledge of the Mode with setting is essential for good therapeutic outcomes and the safety of the patients.

AREAS COVERED

ESU generates high-frequency electric current, which could perform cutting and coagulation for various therapeutic interventions. We review the proper settings for common endoscopic interventions like hemostasis, polypectomy, sphincterotomy, and advanced procedures like endoscopic ultrasound-guided cysto-gastrostomy, bile duct drainage, and endoscopic Ampullectomy. We review the various waveforms of ESU in practice in endoscopy, including special conditions like patients with pacemakers.

EXPERT OPINION

Knowledge of the waveforms' duty cycle and crest factor is necessary. A high-duty cycle and lower crest factor lead to a good cutting effect on the tissue. Endocut is the most commonly used Mode in ESU in endoscopic practices like sphincterotomy and polypectomy. Endocut I mode (effect 1-2, duration 3, interval 3) is used for endoscopic sphincterotomy, while Forced Coag mode (Effect 2, 60 W) controls post-sphincterotomy bleeding. Endocut Q mode (Effect 2-3, duration 1, interval 3) is used for cutting the polyp, while Forced Coag mode (Effect 2, 60 W) is used before cutting for pre-coagulation of the stalk.

Endoscopic submucosal dissection techniques and technology: European Society of Gastrointestinal Endoscopy (ESGE) Technical Review

ESGE suggests conventional endoscopic submucosal dissection (ESD; marking and mucosal incision followed by circumferential incision and stepwise submucosal dissection) for most esophageal and gastric lesions. ESGE suggests tunneling ESD for esophageal lesions involving more than two-thirds of the esophageal circumference. ESGE recommends the pocket-creation method for colorectal ESD, at least if traction devices are not used. The use of dedicated ESD knives with size adequate to the location/thickness of the gastrointestinal wall is recommended. It is suggested that isotonic saline or viscous solutions can be used for submucosal injection. ESGE recommends traction methods in esophageal and colorectal ESD and in selected gastric lesions. After gastric ESD, coagulation of visible vessels is recommended, and post-procedural high dose proton pump inhibitor (PPI) (or vonoprazan). ESGE recommends against routine closure of the ESD defect, except in duodenal ESD. ESGE recommends corticosteroids after resection of  > 50 % of the esophageal circumference. The use of carbon dioxide when performing ESD is recommended. ESGE recommends against the performance of second-look endoscopy after ESD. ESGE recommends endoscopy/colonoscopy in the case of significant bleeding (hemodynamic instability, drop in hemoglobin > 2 g/dL, severe ongoing bleeding) to perform endoscopic hemostasis with thermal methods or clipping; hemostatic powders represent rescue therapies. ESGE recommends closure of immediate perforations with clips (through-the-scope or cap-mounted, depending on the size and shape of the perforation), as soon as possible but ideally after securing a good plane for further dissection.

Expert consensus on the clinical application of high-frequency electrosurgery in digestive endoscopy (2020, Shanghai)

High-frequency electrosurgery has been widely applied in digestive endoscopy with constantly expanding indications. However, high-frequency electrosurgery may cause possible complications such as hemorrhage or perforation during or after the procedure, of which endoscopists must be cautious. Digestive endoscopists must have a firm grasp of the principles of high-frequency electrosurgery as well as its safety issues so as to improve the safety of its clinical application. To this end, experts in gastroenterology and hepatology, digestive endoscopy, surgery, nursing and other related fields were invited to draft a consensus on the clinical application of high-frequency electrosurgery in digestive endoscopy based on relevant domestic and international literatures and their experiences.

Hemorrhage control during gastric endoscopic submucosal dissection: Techniques using uncovered knives

Since the last decade, endoscopic submucosal dissection (ESD) has been used as the standard treatment for superficial gastrointestinal neoplasms. Trainees learning ESD frequently encounter difficulties such as vascularity, peristalsis, and fibrosis during the procedure. Because individual vascularity differs, it generally cannot be consistently avoided. Given that massive hemorrhages can prolong the procedure time and diminish treatment efficacy and that insufficient vessel handling may also increase postoperative bleeding, hemorrhage control during ESD becomes important to ensure procedure safety. This article discusses methods for controlling hemorrhage during gastric ESD. Endoscopists should have a basic understanding of the vascular architecture and the high‐density areas in blood vessels, which are susceptible to intraoperative hemorrhage. Efficient preventative coagulation should be performed in addition to mastering the techniques for hemorrhage control using hemostatic forceps. Techniques useful for preventing intraoperative hemorrhage at every step (e.g. submucosal injection, mucosal incision, and dissection) should be learned. Gaining procedural competence and learning hemorrhage control techniques not only during ESD but also in daily work would help provide safe and effective treatment.

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.

Strategy for esophageal non-epithelial tumors based on a retrospective analysis of a single facility

BACKGROUND

Although most esophageal non-epithelial tumors are benign tumors, such as leiomyomas, they also include gastrointestinal tumors (GISTs); thus, a histopathological diagnosis is indispensable to determine the optimal treatment strategy. However, no consensus has been reached as to the diagnostic methods and treatments for esophageal non-epithelial tumors. The purpose of this study was to evaluate the reliability of the diagnostic methods and treatments for esophageal non-epithelial tumors in our hospital.

METHODS

All 28 cases of esophageal non-epithelial tumors at Kobe University Hospital from 2008 to 2016 were analyzed retrospectively with respect to the diagnostic methods, histopathological diagnosis, and treatments.

RESULTS

Three diagnostic methods, endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA), endoscopic incisional biopsy, and endoscopic submucosal dissection (ESD)/endoscopic mucosal resection (EMR), were performed in our hospital. All GIST cases could be correctly diagnosed by EUS-FNA. Tumors less than approximately 20 mm in diameter and located in the superficial layer are good indications for ESD/EMR, which both play roles in diagnosis and treatment. The final diagnoses by these methods consisted of the following: 13 leiomyomas, 5 GISTs, 3 schwannomas, 2 liposarcomas, 3 cysts, 1 reactive lymphoid hyperplasia, and 1 granulosa cell tumor. Fifteen cases underwent surgery. Enucleation or partial resection was performed for leiomyomas, schwannomas and liposarcomas, while esophagectomy was performed for GISTs. Thus, sufficient management of non-epithelial tumors is achieved.

CONCLUSIONS

Improved endoscopic procedures, including EUS-FNA and ESD/EMR, enabled the appropriate diagnosis and treatment of esophageal non-epithelial tumors.