Advancements in hemostatic strategies for managing upper gastrointestinal bleeding: A comprehensive review.

Upper gastrointestinal (GI) hemorrhage presents a substantial clinical challenge. Initial management typically involves resuscitation and endoscopy within 24 h, although the benefit of very early endoscopy (< 12 h) for high-risk patients is debated. Treatment goals include stopping acute bleeding, preventing rebleeding, and using a multimodal approach encompassing endoscopic, pharmacological, angiographic, and surgical methods. Pharmacological agents such as vasopressin, prostaglandins, and proton pump inhibitors are effective, but the increase in antithrombotic use has increased GI bleeding morbidity. Endoscopic hemostasis, particularly for nonvariceal bleeding, employs techniques such as electrocoagulation and heater probes, with concerns over tissue injury from monopolar electrocoagulation. Novel methods such as Hemospray and Endoclot show promise in creating mechanical tamponades but have limitations. Currently, the first-line therapy includes thermal probes and hemoclips, with over-the-scope clips emerging for larger ulcer bleeding. The gold probe, combining bipolar electrocoagulation and injection, offers targeted coagulation but has faced device-related issues. Future advancements involve combining techniques and improving endoscopic imaging, with studies exploring combined approaches showing promise. Ongoing research is crucial for developing standardized and effective hemorrhage management strategies.

Da Vinci robot-assisted endoscopic full-thickness gastric resection with regional lymph node dissection using a 3D near-infrared video system: a single-center 5-year clinical outcome.

BACKGROUND: Endoscopic full-thickness gastric resection (EFTGR) with regional lymph node dissection (LND) has been used for early gastric cancer (EGC) exceeding the indications for endoscopic submucosal dissection (ESD). The extent of the dissected lymph nodes is crucial. A 3D near-infrared (NIR) video robot system significantly enhances visualization of the lymphatic system. However, this system has not been used in EFTGR with LND. Thus, this study assessed the benefits of the 3D NIR video robot system in a clinical setting. METHODS: Between February 2015 and September 2018, 24 patients with EGC exceeding the indications for ESD were treated with EFTGR and LND using a 3D NIR video system with the da Vinci surgical robot. Indocyanine green (ICG) was injected endoscopically around the tumor, and basin node (BN) dissection around the nodes was examined using the 3D NIR video system of the da Vinci Si surgical robot. Subsequently, robot-assisted EFTGR was performed. The primary outcome was the 5-year survival rate. RESULT: During a 5-year follow-up of all 24 patients, an 80-year-old patient with an ulcer and T2 invasion was lost to follow-up. Among the remaining 23 patients, no mortality or recurrence was observed. CONCLUSION: No metastasis or mortality occurred using the da Vinci robot-assisted EFTGR with LLND and a 3D NIR video system for patients who required radical gastrectomy for EGC in over 5 years. Hence, this may be a safe and effective method for radical gastrectomy; further studies are required confirming its effectiveness.

Endoscopic resection and laparoscopic lymph node dissection for early gastric cancer beyond conventional endoscopic treatment indications: a 10-year outcome study.

BACKGROUND: Endoscopic full-thickness gastric resection (EFTGR) with laparoscopic regional lymph node dissection (LLND) and endoscopic submucosal dissection (ESD) with LLND have been investigated as treatment options for early gastric cancer beyond the absolute indications for ESD. However, comparative studies on the long-term outcomes of these procedures are lacking. This study aimed to analyze and compare the 10-year outcomes of both procedures in a real clinical setting. METHODS: Between January 2009 and December 2013, 28 and 37 patients diagnosed with EGC beyond the absolute indications for ESD were treated with EFTGR with LLND and ESD with LLND, respectively. In both procedures, the dye was injected into the tumor. However, after injection and LLND, EFTGR was performed immediately in the EFTGR with LLND group, whereas LLND was followed by ESD in the ESD with LLND group. The primary endpoint was the 10-year survival rate. RESULTS: The EFTGR with LLND group had one case of local recurrence (3.6%) and mortality (3.6%) each, while the ESD with LLND group had none (0.0% for both); however, the differences were not statistically significant (P = 0.247 for each). Furthermore, there was no significant difference in complications such as ischemia and anastomosis leakage between the groups (P = 0.247). CONCLUSIONS: When the procedures were properly applied, EFTGR with LLND and ESD with LLND did not increase the 10-year mortality in patients with EGC beyond the absolute ESD indications compared with conventional radical gastrectomy.

Efficacy and safety of a submucosal injection solution of sodium alginate for endoscopic resection in a porcine model.

Endoscopic resection techniques require the use of submucosal injection. Normal saline and sodium hyaluronate solutions are mainly used for this purpose, but an ideal solution has not yet been developed. The aim of this study was to assess a new solution, MC-003-a novel submucosal injection solution developed with sodium alginate as the main ingredient. Normal saline, a commercial sodium hyaluronate solution (Endo-Ease), and MC-003 were examined. A total of 18 gastric submucosal cushions were created in the stomachs of six pigs. The height of mucosal elevation was measured sequentially using endoscopic sonography. After euthanizing the animals either 2 h or 5 days after the procedure, pathologic examination was performed for each injection site. Although not statistically significant over the entire study period, MC-003 showed a superior result to normal saline and an equivalent result to Endo-Ease in the submucosal cushion height and its rate of decrease. There were no adverse outcomes after injection of the three solutions and there was no pathologically identified detrimental change in the resected specimens. MC-003 creates a sufficient submucosal fluid cushion without apparent tissue damage. It can be considered as an effective submucosal injection material.

Efficacy and safety of MC-003 solution for endoscopic mucosal or submucosal resection: A prospective, multicenter, randomized, triple-blinded, parallel-group, phase 3 study.

BACKGROUND AND AIMS: The safety and efficacy of solutions for submucosal injection are critical for endoscopic resection of gastric adenomas or early gastric cancers. Although several injectable solutions have been introduced for endoscopic resection, they have some limitations. We aimed to compare the efficacy of the new sodium alginate-based solution MC-003 with that of normal saline (NS, 0.9% sodium chloride). METHODS: In this randomized triple-blind study, 70 patients were initially enrolled for endoscopic mucosal resection or endoscopic submucosal dissection (ESD). The main outcomes included the need for additional injections, completion of en bloc resection, and occurrence of adverse events. RESULTS: Each group finally comprised 34 patients. Complete en bloc resections were achieved in all patients (P = 1.000). The MC-003 group had more peri-neoplasm tissue fibrosis (P = 0.056) and needed fewer additional injections for lesions larger than 15 mm (P = 0.037), located in the distal part (P = 0.007) and during ESD procedures (P = 0.001), whereas the adverse event rate was comparable in both groups. CONCLUSIONS: MC-003 outperformed NS in reducing the need for additional injections during en bloc resection, particularly in larger lesions located in the distal part (where most lesions were found) during ESD procedures, without increasing the incidence of serious adverse events. MC-003 is a promising submucosal injectable solution in real-world clinical settings.

Is it enough to observe less than 2 cm sized gastric SET?

BACKGROUND AND AIMS: The recent surge in demand for screening endoscopy has led to an increased detection of gastric subepithelial tumors (SETs). According to current guideline, SETs less than 2 cm in size are recommended for periodic surveillance. In light of recent advancement in therapeutic endoscopy in resection of small SET, we analyzed the histopathological features and the effectiveness of endoscopic resection for these small SETs. METHODS: Retrospectively study was performed on 74 patients who underwent endoscopic resection of gastric small (≤ 2 cm) upper gastrointestinal tract SETs. The outcomes including histopathology and en bloc resection were analyzed. RESULTS: The mean SET size was 11.69 ± 5.11 mm. The mean procedure time was 81.26 ± 42.53 min. Of the 74 patients, 28 patients had leiomyomas, 26 had gastrointestinal stromal tumors (GISTs), 14 had ectopic pancreas, 4 had lipomas, and 2 had neuroendocrine tumors. Among those with GIST, two patients exhibited high-risk histology. All patients underwent successful and uneventful endoscopy. CONCLUSIONS: Endoscopic resection can be recommended even for the small gastric SETs. In our study, we found that SETs with a size of less than 2 cm have significant proportion of GISTs which harbor malignant transformation potential.

A comparative study of magnifying endoscopy with narrow-band image and endocytoscopy in the diagnosis of gastric neoplasm: a pilot study.

BACKGROUND/AIMS: Endoscopic technologies have recently advanced to optimize the detection and diagnosis of gastric lesions. Endocytoscopy aids in the virtual realization of histology. Herein, we aimed to investigate gastric lesions using single-stain endocytoscopy and compare them using magnifying endoscopy with narrow-band imaging (ME-NBI) in terms of diagnostic yield in vivo. METHODS AND METHODS: In the present prospective study, we registered 24 patients with gastric neoplasms and retrospectively reviewed their images. Three endoscopists reviewed the images of gastric neoplasms using white light, ME-NBI, and endocytoscopy. The diagnostic yield of endocytoscopy in early gastric cancer (EGC) was assessed using histopathology as the gold standard. RESULTS: Endocytoscopy was performed in 24 patients with gastric neoplasms. Of these, 15 patients had adenocarcinomas, while nine patients had low-grade dysplasia. The sensitivity, specificity, and accuracy of endocytoscopy for EGC detection were reported as 80.0% [95% confidence interval (CI), 51.9-95.7], 66.7% (95% CI, 58.4-91.9), and 75.0% (95% CI, 53.3-90.2) by endoscopist A; 80.0% (95% CI, 51.9-95.7), 44.4% (95% CI, 13.7-78.8), and 66.7% (95% CI, 44.7-84.4) by endoscopist B; and 93.3% (95% CI, 68.1-99.8), 55.6% (95% CI, 21.2-86.3), and 79.2% (95% CI, 57.9-92.8) by endoscopist C; these findings were not inferior to NBI. The inter-observer agreement, κ statistic = 0.67 (95% CI, 0.43-0.90) was favorable. CONCLUSION: Endocytoscopy aid in the diagnosis of EGC because of its better sensitivity and accuracy compared to NBI or white-light imaging. However, further large-scale studies are required to confirm our findings.

Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: adenoma ≥10 mm in size; 3 to 5 (or more) adenomas; tubulovillous or villous adenoma; adenoma containing high-grade dysplasia; traditional serrated adenoma; sessile serrated lesion containing any grade of dysplasia; serrated polyp of at least 10 mm in size; and 3 to 5 (or more) sessile serrated lesions. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Comparison Trial between I-SCAN-Optical Enhancement and Chromoendoscopy for Evaluating the Horizontal Margins of Gastric Epithelial Neoplasms.

Background/Aims: Endoscopic submucosal dissection is a widely used treatment for gastric epithelial neoplasms. Accurate delineation of the horizontal margins is necessary for the complete resection of gastric epithelial neoplasms. Recently, image-enhanced endoscopy has been used to evaluate horizontal margins of gastric epithelial neoplasms. The aim of this study was to investigate whether I-SCAN-optical enhancement (I-SCAN-OE) is superior to chromoendoscopy in evaluating the horizontal margin of gastric epithelial neoplasms. Methods: This was a multicenter, prospective, and randomized trial. The participants were divided into two groups: I-SCAN-OE and chromoendoscopy. For both groups, we first evaluated the horizontal margins of early gastric cancer or high-grade dysplasia using white-light imaging, and then evaluated, the horizontal margins using I-SCAN-OE or chromoendoscopy. We devised a unique scoring method based on the pathological results obtained after endoscopic submucosal dissection to accurately evaluate the horizontal margins of gastric epithelial neoplasms. The delineation scores of both groups were compared, as were the ratios of positive/negative horizontal margins. Results: In total, 124 patients were evaluated for gastric epithelial neoplasms, of whom 112 were enrolled in the study. A total of 112 patients participated in the study, and 56 were assigned to each group (1:1). There was no statistically significant difference in the delineation scores between the groups (chromoendoscopy, 7.80±1.94; I-SCAN-OE, 8.23±2.24; p=0.342). Conclusions: I-SCAN-OE did not show superiority over chromoendoscopy in delineating horizontal margins of gastric epithelial neoplasms.

Korean guidelines for postpolypectomy colonoscopic surveillance: 2022 revised edition.

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for the management of advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: (1) adenoma ≥10 mm in size; (2) 3 to 5 (or more) adenomas; (3) tubulovillous or villous adenoma; (4) adenoma containing high-grade dysplasia; (5) traditional serrated adenoma; (6) sessile serrated lesion (SSL) containing any grade of dysplasia; (7) serrated polyp of at least 10 mm in size; and (8) 3 to 5 (or more) SSLs. More studies are needed to fully comprehend the patients most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

[Korean Guidelines for Postpolypectomy Colonoscopic Surveillance: 2022 Revised Edition].

Colonoscopic polypectomy is effective in decreasing the incidence and mortality of colorectal cancer (CRC). Premalignant polyps discovered during colonoscopy are associated with the risk of metachronous advanced neoplasia. Postpolypectomy surveillance is the most important method for managing advanced metachronous neoplasia. A more efficient and evidence-based guideline for postpolypectomy surveillance is required because of the limited medical resources and concerns regarding colonoscopy complications. In these consensus guidelines, an analytic approach was used to address all reliable evidence to interpret the predictors of CRC or advanced neoplasia during surveillance colonoscopy. The key recommendations state that the high-risk findings for metachronous CRC following polypectomy are as follows: 1) adenoma ≥10 mm in size; 2) 3-5 (or more) adenomas; 3) tubulovillous or villous adenoma; 4) adenoma containing high-grade dysplasia; 5) traditional serrated adenoma; 6) sessile serrated lesion (SSL) containing any grade of dysplasia; 7) serrated polyp of at least 10 mm in size; and 8) 3-5 (or more) SSLs. More studies are needed to fully comprehend the patients who are most likely to benefit from surveillance colonoscopy and the ideal surveillance interval to prevent metachronous CRC.

Mucosal Injury During Per-oral Endoscopic Myotomy: A Single-Center Experience.

BACKGROUND: Peroral endoscopic myotomy is associated with a low risk of adverse events. Mucosal injury is the most common intraprocedural adverse event of peroral endoscopic myotomy. Severe mucosal injury may cause serious consequences, such as esophageal leak and mediastinitis, which affect the outcome of the procedure and prolong hospital stay. The aim of the present study was to determine the characteristics, predictors, and management approaches for unintended mucosal injury during peroral endoscopic myotomy. METHODS: A total of 211 patients who underwent peroral endoscopic myotomy between November 2014 and June 2019 were enrolled in this study. Mucosal injury was defined according to a previous study and maintained in the endoscopy database. Patient-related and procedure-related factors were compared between patients with and without mucosal injury. Multivariate analysis was performed after adjusting for confounding factors. RESULTS: A total of 206 patients were eligible for study enrollment. Of these, 44 experienced mucosal injury, with an overall frequency of 21.4% (44/206). On multivariable analysis, mucosal injury was associated with submucosal fibrosis (odds ratio, 8.33; P = .024), intraprocedural bleeding (OR, 14.29; P < .001), endoscopic diameter of 9.9 mm (OR, 4.389; P = .006), and procedure duration over 60 minutes (OR, 1.016; P = .034). CONCLUSION: Mucosal injury is a significant event encountered during peroral endoscopic myotomy, affecting its short- and long-term outcomes. Intra-procedural bleeding, endoscopic submucosal fibrosis, and use of an endoscope with a large outer diameter have been found to be significant predictors of mucosal injury. Endoscopists should pay more attention to risk factors associated with mucosal injury to avoid adverse events.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation.

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Such cardiopulmonary complications are usually temporary, and most patients recover without sequelae. However, these events may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

[2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation].

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Cardiopulmonary complications are usually temporary. Most patients recover without sequelae. However, they may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation.

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Cardiopulmonary complications are usually temporary. Most patients recover without sequelae. However, they may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

Durability of per-oral endoscopic myotomy beyond 6 years.

Background and study aims The aim of this study was to assess long-term clinical outcomes beyond 6 years in patients who underwent per-oral endoscopic myotomy (POEM) for the treatment of achalasia. Patients and methods Patients with achalasia who underwent POEM between 2010 and 2012 and had follow-up of at least 6 years were retrospectively identified at eight tertiary care centers. The primary outcome evaluated was clinical success defined by an Eckardt symptom score (ESS) ≤ 3 for the duration of the follow-up period. The clinical success cohort was compared to failure (ESS > 3 at any time during follow-up) in order to identify characteristics associated with symptom relapse. The incidence of patient-reported gastroesophageal reflux (GER) was also evaluated. Results Seventy-three patients with 6-year follow-up data were identified. Sustained clinical remission was noted in 89 % (65/73) at 6-years. Mean ESS decreased from 7.1 ±â€Š2.3 pre-procedure to 1.1 ±â€Š1.1 at 6 years ( P  < 0.001). Symptomatic reflux was reported by 27 of 72 patients (37.5 %). Type I achalasia (OR 10.8, P  = 0.04) was found to be associated with clinical failure on logistic regression analysis. Conclusions In patients with achalasia, POEM provides high initial clinical success with excellent long-term outcomes. There are high rates of patient-reported gastroesophageal reflux post-procedure which persist at long-term follow-up.

[Clinical and Technical Guideline for Endoscopic Ultrasound-guided Tissue Acquisition of Pancreatic Solid Tumor: Korean Society of Gastrointestinal Endoscopy].

Endoscopic ultrasound (EUS)-guided tissue acquisition of pancreatic solid tumor requires a strict recommendation for its proper use in clinical practice because of its technical difficulty and invasiveness. The Korean Society of Gastrointestinal Endoscopy appointed a Task Force to draft clinical practice guidelines for EUS-guided tissue acquisition of pancreatic solid tumor. The strength of recommendation and the level of evidence for each statement were graded according to the Minds Handbook for Clinical Practice Guideline Development 2014. The committee, comprising a development panel of 16 endosonographers and an expert on guideline development methodology, developed 12 evidence-based recommendations in eight categories intended to help physicians make evidence- based clinical judgments with regard to the diagnosis of pancreatic solid tumor. This clinical practice guideline discusses EUS-guided sampling in pancreatic solid tumor and makes recommendations on circumstances that warrant its use, technical issues related to maximizing the diagnostic yield (e.g., needle type, needle diameter, adequate number of needle passes, sample obtaining techniques, and methods of specimen processing), adverse events of EUS-guided tissue acquisition, and learning-related issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This guideline may not be applicable for all clinical situations and should be interpreted in light of specific situations and the availability of resources. It will be revised as necessary to cover progress and changes in technology and evidence from clinical practice.

Clinical Practice Guidelines for the Endoscopic Management of Peripancreatic Fluid Collections.

Endoscopic ultrasonography-guided intervention has gradually become a standard treatment for peripancreatic fluid collections (PFCs). However, it is difficult to popularize the procedure in Korea because of restrictions on insurance claims regarding the use of endoscopic accessories, as well as the lack of standardized Korean clinical practice guidelines. The Korean Society of Gastrointestinal Endoscopy appointed a Task Force to develop medical guidelines by referring to the manual for clinical practice guidelines development prepared by the National Evidence-Based Healthcare Collaborating Agency. Previous studies on PFCs were searched, and certain studies were selected with the help of experts. Then, a set of key questions was selected, and treatment guidelines were systematically reviewed. Answers to these questions and recommendations were selected via peer review. This guideline discusses endoscopic management of PFCs and makes recommendations on Indications for the procedure, pre-procedural preparations, optimal approach for drainage, procedural considerations (e.g., types of stent, advantages and disadvantages of plastic and metal stents, and accessories), adverse events of endoscopic intervention, and procedural quality issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This will be revised as necessary to address advances and changes in technology and evidence obtained in clinical practice and future studies.

Clinical Practice Guidelines for the Endoscopic Management of Peripancreatic Fluid Collections.

Endoscopic ultrasonography-guided intervention has gradually become a standard treatment for peripancreatic fluid collections (PFCs). However, it is difficult to popularize the procedure in Korea because of restrictions on insurance claims regarding the use of endoscopic accessories, as well as the lack of standardized Korean clinical practice guidelines. The Korean Society of Gastrointestinal Endoscopy (KSGE) appointed a Task Force to develope medical guidelines by referring to the manual for clinical practice guidelines development prepared by the National Evidence-Based Healthcare Collaborating Agency. Previous studies on PFCs were searched, and certain studies were selected with the help of experts. Then, a set of key questions was selected, and treatment guidelines were systematically reviewed. Answers to these questions and recommendations were selected via peer review. This guideline discusses endoscopic management of PFCs and makes recommendations on Indications for the procedure, pre-procedural preparations, optimal approach for drainage, procedural considerations (e.g., types of stent, advantages and disadvantages of plastic and metal stents, and accessories), adverse events of endoscopic intervention, and procedural quality issues. This guideline was reviewed by external experts and suggests best practices recommended based on the evidence available at the time of preparation. This will be revised as necessary to address advances and changes in technology and evidence obtained in clinical practice and future studies.

Endoscopic application of mussel-inspired phenolic chitosan as a hemostatic agent for gastrointestinal bleeding: A preclinical study in a heparinized pig model.

Marine mussels secrete adhesive proteins to attach to solid surfaces. These proteins contain phenolic and basic amino acids exhibiting wet adhesion properties. This study used a mussel-inspired hemostatic polymer, chitosan-catechol, to treat gastrointestinal bleeding caused by endoscopic mucosal resection in a heparinized porcine model. We aimed to evaluate the hemostatic efficacy and short-term safety of this wet adhesive chitosan-catechol. We used 15 heparinized pigs. Four iatrogenic bleeding ulcers classified as Forrest Ib were created in each pig using an endoscopic mucosal resection method. One ulcer in each pig was untreated as a negative control (no-treatment group). The other three ulcers were treated with gauze (gauze group), argon plasma coagulation (APC group), and chitosan-catechol hemostatic agent (CHI-C group) each. The pigs were sacrificed on Days 1, 5, and 10, and histological examination was performed (n = 5 per day). Rapid hemostasis observed at 2 min after bleeding was 93.3% (14/15) in the CHI-C group, 6.7% (1/15) in the no-treatment group, 13.3% (2/15) in the gauze group, and 86.7% (13/15) in the APC group. No re-bleeding was observed in the CHI-C group during the entire study period. However, a few re-bleeding cases were observed on Day 1 in the no-treatment, gauze, and APC groups and on Day 5 in the gauze and APC groups. On histological analysis, the CHI-C group showed the best tissue healing among the four test groups. Considering the results, chitosan-catechol is an effective hemostatic material with reduced re-bleeding and improved healing.