Efficacy of a reverse-phase polymer as a submucosal injection solution for EMR: a comparative study (with video)

• Published in: Gastrointestinal endoscopy Vol. 69; no. 6; pp. 1135 - 1139
• Main Authors: Fernández-Esparrach, Gloria, MD, PhD, Shaikh, Sohail N., MD, Cohen, Arielle, BS, Ryan, Michele B., MS, Thompson, Christopher C., MD, MSc, FACG, FASGE
• Format: Journal Article Reference
• Language: English
• Published: Maryland heights, MO Mosby, Inc 01.05.2009; Elsevier
• Subjects: Animals; Biological and medical sciences; Colon - pathology; Colon - surgery; Colonoscopy - methods; Digestive system. Abdomen; Endoscopy; Gastric Mucosa - pathology; Gastric Mucosa - surgery; Gastroenterology and Hepatology; Gastroenterology. Liver. Pancreas. Abdomen; Gastroscopy - methods; Gels; Hypromellose Derivatives; Injections; Intestinal Mucosa - pathology; Intestinal Mucosa - surgery; Investigative techniques, diagnostic techniques (general aspects); Medical sciences; Methylcellulose - analogs & derivatives; Poloxamer - administration & dosage; Solutions; Stomach, duodenum, intestine, rectum, anus; Surface-Active Agents; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Surgery of the digestive system; Swine; hydroxypropyl methylcellulose; analysis of variance; ANOVA; HPMC; Endoscopic mucosal resection; Polymer; Submucosa; Comparative study
• ISSN: 0016-5107; 1097-6779
• DOI: 10.1016/j.gie.2008.07.032

Introduction Reverse-phase polymers undergo a temperature-dependent liquid-to-gel transition that may provide a more durable cushion for EMR and could yield improvements in safety and efficacy. Objective Our purpose was to assess the efficacy of poloxamer solution PS137-25 as a submucosal injection. Design Comparative study among 3 different solutions for EMR using ex vivo and in vivo porcine models. Interventions A total of 120 gastric submucosal cushions were performed in fresh ex vivo porcine stomachs with saline solution 0.9% (n = 40), hydroxypropyl methylcellulose (HPMC) (n = 40), and PS137-25 (n = 40). Five in vivo porcine colon EMRs were then performed. Main Outcome Measurements Height and duration of submucosal cushions were measured in the ex vivo model, and the usefulness of reverse-phase polymers was assessed by in vivo en bloc resection. Results Ex vivo: The height of mucosal elevation was greater with PS137-25 (10.3 ± 2.2 mm) than with saline solution (8.3 ± 2.6 mm) or HPMC (9.05 ± 2.3 mm, not significant). All submucosal elevations with PS137-25 lasted longer (more than 20 minutes) than with saline solution (20.9 ± 11 minutes, P < .01) or HPMC (89 ± 32 minutes, P < .01). After 120 minutes, the elevations obtained with PS137-25 showed no differences in size, shape, or consistency from initial measurements. In vivo: All 5 EMRs were successfully performed after 1 injection of PS137-25. No repeat injections were needed. During resection, a large gel cushion was noted. Conclusions Mucosal elevation with PS137-25 is more durable than with other substances, with no changes in size or consistency observed over 120 minutes. Additionally, reverse-phase polymers performed well in in vivo colon EMRs. These results suggest that reverse-phase polymers may provide increased safety and efficacy for EMR procedures.