SSAT Abstracts Su1004 TECHNICAL SKILLS TRAINING FOR THE ENDOSCOPIC MANAGEMENT OF NON-VARICEAL UPPER GASTROINSTESTINAL BLEEDING (NVUGIB): A SCOPING REVIEW OF QUANTITATIVE AND QUALITATIVE EVIDENCE Shawn M. Purnell, Joseph J. Nguyen-Lee, Sean M. Stokes, Mary McFarland, Tallie Casucci, Brian J. Dunkin, Daniel Vargo INTRODUCTION Technical skills training for the endoscopic management of NVUGIB continues to prove challenging. Most training occurs during high-stakes, real-world cases supervised by a proctor resulting in significant variability in trainee case volume, autonomy, and guidance across institutions. As a result, a low-cost, readily available, effective simulator is needed for deliberate practice in managing NVUGIB. In preparation for creation of such a simulator, we conducted a scoping review to identify available training models for NVUGIBs and assess their effectiveness. METHODS The scoping review was conducted in accordance with the framework developed by Arksey and O’Malley, and utilized the PRISMA_ScR checklist for reporting guidance. MEDLINE, EMBASE, Cochrane, LILACS, ERIC, and Web of Science searches were conducted focusing on endoscopy of the upper gastrointestinal tract, bleeding, and training utilizing subject headings and key words. Covidence was used to screen articles by three independent reviewers and standardized data extraction was performed in Excel (Figure). RESULTS Fifteen studies were identified: 5 randomized control trials (RCTs), 5 quasi-experimental studies, and 5 reviews. Of the RCTs and quasi-experimen- tal studies, techniques for endoscopic hemostasis included injection (9/10), clip application (9/10), and electrosurgery (7/10). Two in-vivo and two ex-vivo porcine models were described (EASIE and CompactEASIE). Two in-vivo studies demonstrated realistic and reproducible NVUGIBs, but no utility in improving trainees’ technical skills. CompactEASIE was the most studied simulation model (8/10) and developed from the EASIE as a lightweight, more practical alternative with comparable function. RCTs have shown that a structured training curriculum using the CompactEASIE significantly improved the ability of GI fellows to gain hemostatic control of NVUGIBs in both simulated and real clinical settings. Additionally, CompactEASIE training significantly improved novice interventional endoscopy skills and was capable of improving performance of hemostasis procedures in a 1-day training course. Studies are ongoing to further elucidate simulation training effects on clinical outcomes and assess the need for refresher simulation training. CONCLUSION Only four simulation models are described in the literature for managing NVUGIB. Two require use of a live porcine model and have not demonstrated training utility. Two use ex-vivo porcine tissue and, when incorporated into a structured training curriculum, significantly improve performance of endoscopic management of NVUGIBs by participants of varying experience. All four models are limited by high cost, accessibility, and a requirement for specialized ancillary staff. This work serves as a needs analysis for a better simulation platform to rehearse management of NVUGIBs. S-1436 SSAT Abstracts Su1005 ASSESSMENT OF AN EX VIVO BOVINE LARGE BOWEL ENDOSCOPIC SUBMUCOSAL DISSECTION (ESD) TRAINING MODEL: OBSERVATIONS, PROBLEMS ENCOUNTERED AND SUGGESTED REMEDIES. Dasuni Niyagama Gamage, Neil Mitra, Carl Winkler, Jaspreet Sandhu, Erica Pettke, Abhinit Shah, Xiaohong Yan, Vesna Cekic, Shantha Kumara HMC, Nipa Gandhi, Richard L. Whelan Introduction: ESD is the gold standard for sessile colon adenomas. In Japan, before colon cases, trainees do 40-60 human gastric ESD cases. Gastric ESD training in the West is not feasible. Learning colonic ESD in humans is a dangerous, challenging, and lengthy approach (case volume dependent). An alternative is to use ex vivo tissue. The authors rely heavily on an ex vivo bovine large bowel model which utilizes harvested but intact colon/rectum/ anus; mucosal “lifts” can be generated, insufflation is required, and perforation is a risk. Doing many bovine cases allows trainees to develop a resection strategy. However, the use of dead tissue is a challenge and there is a learning curve for this model. This poster will critique the bovine model and suggest solutions to model related problems. Methods: Intact bovine large bowel is harvested soon after sacrifice. The bowel is mechanically cleansed and refrigerate the colon until use. The long colon is placed on a peg board and held in place with rubber bands. The location of the tattooed “polyp” can be varied. A pediatric colonoscope, sclerotherapy needle, electrosurgical generator, bovey pad, lift solution, and needle knife are used to carry out ESD. The resected disc and colon wall defect are inspected post removal. Case duration, quality of resection, and deep wall injuries noted. Results: To date, 32 bovine colons have been used for ESD training. As a result the ESD/EMR clinical completion rate has increased from under 40% to 78%. Spring clips occlude the bowel proximally. The intact anus usually maintains pneumocolon, but, if needed, plastic zip ties around the distal bowel can be used. During early cases it was often difficult to maintain a “lift” because of poor tissue integrity (leakage from mucosal tears) which makes ESD very difficult. Histologic evaluation of colon lifts revealed rapid mucosal degradation; gut bacteria are a likely factor. The following steps delayed decomposition and improved lift quality; rapid mechanical cleansing, antibiotic solution instillation, refrigeration at all times, and use within 4-6 hours. The external colon should be kept moist during ESD. The above measures facilitated ESD. Of note, the bovine large bowel diameter was notably larger vs humans; this makes it harder to keep scope tip and adjacent shaft tangential to the polyp (critical for ESD). Colon diameter can be reduced by placing large plastic spring clips along the bowel wall. Conclusion: The ex vivo bovine model allows many ESD cases to be done within a limited time period. Although more realistic than other models, lift maintenance is a problem due to rapid mucosal degradation; large diameter colons and air leakage are also problematic. Remedies to these problems are; bowel cleansing, antibiotic use, refrigera- tion, spring clip application, zip ties, and ESD within 4-6 hours. Su1091 SUBEPITHELIAL MICRORNA EXPRESSION DURING ADAPTATION TO MASSIVE SMALL BOWEL RESECTION Adam Bajinting, Kristen Seiler, Matt Kanke, Michael T. Shanahan, Praveen Sethupathy, Brad W. Warner Background: Intestinal adaptation is a physiological response to shortened gut following a massive small bowel resection (SBR). Adaptation is characterized by lengthened villi and deepened crypts to compensate for lost absorptive surface area. While the morphological and certain functional aspects are well characterized at the epithelial level, changes occurring in the subepithelium (subepithelial tissue, or SET) are poorly understood. Understanding contributions of SET to intestinal adaptation is potentially important because SET has previously been shown to drive intestinal stem cell (ISC) proliferation and epithelial regenera- tion in other damage-response scenarios. To begin addressing this gap in our understanding of adaptation, we analyzed the microRNA (miRNA) profile of SET from mice that underwent SBR vs sham surgery. miRNA are small noncoding segments of RNA that regulate expression at target regions of the transcribed genome. Clinically miRNAs may be a potential way to modify the genetic expression landscape of the gut in order to accelerate intestinal adaptation in patients suffering from short bowel syndrome (SBS). Methods: C57BL/6 mice were subjected to 50% proximal SBR or sham operation. At day 3 after surgery (a time of crypt hypertrophy and increase epithelial proliferation), SET from remnant ileum was harvested and analyzed for miRNA expression. Results: Using a cut off value of p =/< 0.5, we identified 18 miRNA that were differently expressed between SET from sham and SBR mice. The top nine miRNAs upregulated in SBR or downregulated in SBR are presented in Tables 1 and 2 respectively. Literature was queried for what is known about these miRNAs, revealing that they may be involved in angiogenic, immune, metabolic, stem cell, and proliferative responses following SBR. Moreover, we identified miRNAs that are involved in the regenera- tive processes of other organs. Conclusion: Here, we demonstrate that the miRNA expression profiles of SET between sham and SBR mice are significantly different. Moreover, the identified miRNAs that are involved in the regenerative process of other organs has led us to believe the potential role of SET in the intestinal regenerative response. Given SET’s role in epithelial regeneration and the potential for miRNA to be used clinically to accelerate intestinal adaptation, this analysis sets the groundwork for future mechanistic studies on the relation- ship between miRNA and SBS. Table 1. Unregulated miRNA in SET for SBR vs. SHAM mice