Effective, safe and efficient porcine model of Forrest Ib bleeding gastric and colonic ulcers.

BACKGROUND: Developing effective gastrointestinal (GI) bleeding animal models is necessary to advance endoscopic hemostasis methods and train endoscopists on their use. Our aim, therefore, was to develop an effective and safe porcine GI bleeding model in the stomach and colon of large and small-sized oozing-type ulcers. METHODS: Gastric and colonic bleeding ulcers were created using either a hybrid endoscopic submucosal dissection (ESD) technique or a cap-assisted endoscopic mucosal resection (EMR-C) technique in 14 pigs. Prior to ulcer creation, animals were treated with either oral apixaban or intravenous (IV) unfractionated heparin anticoagulation in combination with clopidogrel and aspirin. The primary outcome was the technical success of inducing oozing-type Forrest Ib bleeding ulcers. Secondary outcomes included ulcer diameter, number, creation time and the number of complications associated with each technique. RESULTS: Using hybrid ESD and IV heparin anticoagulation, bleeding was observed in 21/23 (91.3%) gastric ulcers and 6/7 (85.7%) colonic ulcers created. The mean diameter and ulcer creation time were 2.3 ± 0.3 cm and 5.3 ± 0.5 min, respectively, for gastric ulcers and 2.2 ± 0.4 cm and 4.06 ± 0.6 min, respectively, for colonic ulcers. Using EMR-C and IV heparin anticoagulation, bleeding was observed in 14/15 (93.3%) gastric ulcers and 6/6 (100%) colonic ulcers created. The mean diameter and ulcer creation time were 0.8 ± 0.2 cm and 2.1 ± 0.5 min, respectively, for gastric ulcers and 0.7 ± 0.2 cm and 1.7 ± 0.3 min, respectively, for colonic ulcers. None of the ulcers created in animals anticoagulated with apixaban developed bleeding. None of the 14 pigs developed any complications. CONCLUSION: We have demonstrated the effectiveness and safety of a porcine GI bleeding model utilizing IV heparin anticoagulation and either hybrid ESD or EMR-C techniques to create oozing-type bleeding ulcers in the stomach and colon with customizable size.

Jet injection of dyed saline facilitates efficient peroral endoscopic myotomy.

BACKGROUND AND STUDY AIMS: Peroral endoscopic myotomy (POEM) is technically challenging and time consuming. Repeated injection of dyed saline during tunneling is performed to enhance the demarcation between the submucosal layer and the muscularis propria. This process requires exchanging the knife for a catheter to spray dyed saline and is time consuming. This study aimed to describe a new method of injecting dyed saline through an integrated water jet channel during POEM. PATIENTS AND METHODS: POEM was performed using a triangular tip knife. Repeated jet injection of saline mixed with indigo carmine was performed whenever the submucosal dissection plane became unclear. RESULTS: The study cohort consisted of nine patients (8 achalasia, 1 Jackhammer esophagus). All procedures were technically feasible and successful without any complications and resulted in the patients' Eckhardt's scores returning to normal. The mean submucosal tunnel length was 13.3 cm and the mean myotomy length was 9.9 cm. The mean procedure time was 127 minutes. CONCLUSION: The modified POEM technique with use of jet injection of dyed saline is simple and may render POEM easier and more efficient than the standard dissection method.