New applications for endoscopy: the emerging field of endoluminal and transgastric bariatric surgery
The purpose of this study was to evaluate a novel, intraluminally deployed anastomotic device (AD). A survival study was conducted in 18 farm pigs. One early subject was excluded and replaced due to premature expiration. Six animals were placed in 1 of 3 cohorts, with euthanasia and AD explantation planned at 2, 4, and 6 weeks. A distal small intestinal side-side [functional end-end] anastomosis using the AD was performed via midline laparotomy. Fluoroscopy with double-contrast dilute barium and burst pressure measurements were performed in 4 animals in each group. Two animals in each cohort underwent fluoroscopy without contrast and resection for histology. Mucosal healing, inflammation, anastomotic alignment of the muscularis propria, and fibrosis were graded on a 4-point scale. All animals survived to the date of planned euthanasia except the excluded subject, who expired from causes unrelated to the device. Normal weight gain was seen in all. Sixteen of 18 devices sloughed prior to extraction without evidence of injury or obstruction during the survival period or at necropsy. Filling pressures of >200 mm Hg were reached; no leakage was seen. Mucosal healing and continuity were graded good to excellent at 2 weeks and excellent at 4 and 6 weeks. Inflammation improved with time, with moderate change at 2 weeks and mild at 6 weeks. Anastomotic fibrosis was mild at 2 weeks, mild to minimal at 4 weeks, and minimal at 6 weeks. The anastomotic alignment was 100 per cent except in 1 animal at 2 weeks with >50 per cent but <100 per cent alignment. The AD resulted in a stable, functional anastomosis without narrowing. All tested anastomoses withstood supraphysiologic insufflation pressures without evidence of disruption. The applicability of this novel device will be explored for use in other gastrointestinal and biliary anastomoses using minimally invasive deployment techniques.