Natural orifice transluminal endoscopic one-anastomosis gastric bypass: a feasibility study using porcine model

Feasibility of a new bariatric fully endoscopic duodenal-jejunal bypass: a pilot study in adult obese pigs

This study assessed a new natural orifice transluminal endoscopic surgery (NOTES) bariatric endoscopic procedure in obese adult pigs. This 14-week prospective study compared 6 adult male Yucatan test pigs with baseline mean age 1.5 years to 2 control pigs. The test pigs received a fully endoscopic NOTES-based duodenal-jejunal bypass including measurement of the bypassed limb and creation of a gastrojejunal anastomosis (GJA) using a gastrojejunal lumen-apposing metal stent (GJ-LAMS) at Week 0, placement of a duodenal exclusion device (DED) at Week 2, and endoscopic examinations at Weeks 6 and 10. At Week 14, the pigs were sacrificed for necropsy. All endoscopic procedures were technically successful. By Week 14, the controls had gained a mean 1.1 ± 2.1 kg (+ 1.6%) while the intervention animals lost a mean 6.8 ± 3.9 kg (- 10.5%) since baseline. GJ-LAMS migrations occurred in 3 pigs, two of which also had DED migration and/or partial dislocation. Two other pigs died, one with aberrant splenic vein positioning near the GJA and the other from an unknown cause. An endoscopic bariatric bypass procedure with controlled bypass length was technically successful in all the cases and led to weight loss in test animals. Safety concerns must be further addressed.

Natural Orifice Transluminal Endoscopic One-Anastomosis Gastric Bypass: a Feasibility Study Using Human Cadavers

BACKGROUND

Endoscopic bariatric therapies (EBT) has emerged as an effective treatment in the management of the patient with obesity. Unfortunately, most procedures involve only the restriction of gastric volume without altering the underlying metabolism. The objective of this study was to investigate the practicability and limitations of the metabolic altering procedures: "One anastomosis gastric bypass (OAGB)" with "natural orifice transluminal endoscopic surgery (NOTES)" on human cadavers.

METHODS

We performed OAGB with NOTES approach in 3 human cadavers. The steps of the procedure can be divided as follows: step 1, endoscopic sleeve gastroplasty (ESG); step 2, trans-gastric access to peritoneal cavity; step 3, identification of suitable loop of jejunum; step 4, introduction of the jejunal loop into the stomach; step 5, creation of the gastro-jejunostomy with lumen-apposing metal stent (LAMS); step 6, gastric pylorus occlusion with overstitch.

RESULTS

We performed OAGB with NOTES in 3 human cadavers with bypassed bilio-pancreatic limb of 55, 75, and 105 cm from the pylorus. The average weight for the cadavers was 64.9 kg (61.2-71.7 kg). The mean procedure time was 157 min. The optimal bypassed length for the procedure was 105 cm.

CONCLUSIONS

This study has provided proof-of-principle in a pre-clinical cadaveric model that NOTES approach can be used to perform OAGB and, therefore, merits additional evaluation and consideration in surviving porcine model.

Endoscopic sleeve gastroplasty

Since its first description in 2013, robust evidence supporting the efficacy and safety of the endoscopic sleeve gastroplasty (ESG) has been on the rise. A large case series and meta-analysis report supported results up to 24 months, while some other studies already described 5-year data. If associated with pharmacotherapy, the ESG may help one to achieve weight loss similar to that of surgical sleeve gastrectomy. Though the results of the ongoing randomized trials on ESG are awaited, currently available data support the clinical use of the ESG, especially for patients who are refusing or unfit for bariatric surgery.

First fully endoscopic metabolic procedure with NOTES gastrojejunostomy, controlled bypass length and duodenal exclusion: a 9-month porcine study

We conducted a pilot study of a potential endoscopic alternative to bariatric surgery. We developed a Natural Orifice Transluminal Endoscopic Surgery (NOTES) gastric bypass with controlled bypass limb length using four new devices including a dedicated lumen-apposing metal stent (GJ-LAMS) and pyloric duodenal exclusion device (DED). We evaluated procedural technical success, weight change from baseline, and adverse events in growing Landrace/Large-White pigs through 38 weeks after GJ-LAMS placement. Six pigs (age 2.5 months, mean baseline weight 26.1 ± 2.7 kg) had initial GJ-LAMS placement with controlled bypass limb length, followed by DED placement at 2 weeks. Technical success was 100%. GJ-LAMS migrated in 3 of 6, and DED migrated in 3 of 5 surviving pigs after mucosal abrasion. One pig died by Day 94. At 38 weeks, necropsy showed 100–240 cm limb length except for one at 760 cm. Weight gain was significantly lower in the pigs that underwent endoscopic bypass procedures compared to expected weight for age. This first survival study of a fully endoscopic controlled bypass length gastrojejunostomy with duodenal exclusion in a growing porcine model showed high technical success but significant adverse events. Future studies will include procedural and device optimizations and comparison to a control group.