A new in vivo method for testing closures of gastric NOTES incisions using leak of the closure or gastric yield as endpoints

Percutaneous Transgastric Duodenal Stenting and Gastrostomy Repair Using a Vascular Closure Device: Proof of Concept in a Porcine Model

Introduction. Gastroduodenal stenting is efficacious and safe in both benign and malignant foregut diseases. Transgastric duodenal stenting has been described and however requires a gastrostomy tube to remain in situ for 4 to 6 weeks post-procedure which can lead to complications. We present a technique for immediate gastric repair using a suture-mediated vascular closure device, without the need for a gastrostomy tube in porcine models. Methods. Percutaneous access into the stomach was achieved using fluoroscopy. Two or 3 Perclose Proglide devices were pre-deployed. The tract was dilated and a wire advanced into the distal duodenum. A 15.5 cm covered enteric stent was delivered through the gastrostomy, deployed and position confirmed. The gastrostomy was closed using Perclose Proglide sutures. Necropsy leak pressure measurement was performed to assess integrity of gastrostomy closure in the porcine models. Results. Two (n = 8) or 3 (n = 2) Perclose Proglide devices were deployed in ten porcine models, with 1 misfire (4.5%). Percutaneous transgastric access and stent delivery was successful in all porcine models. Mean leak pressure in the animals with adequately deployed devices was 219 mmHg (range 172 mmHg-270 mmHg). Conclusion. This study demonstrates percutaneous transgastric duodenal stenting with immediate gastric repair using suture-mediated vascular closure devices is a feasible procedure.

Gastrotomy Healing After Transgastric Peritoneoscopy: A Randomized Study in a Pig Model

INTRODUCTION

Reliable closure and infection prevention are the main barriers for implementation of pure transgastric peritoneoscopy. The primary aim of this study was to assess healing of over the scope clip (OTSC) closed gastrotomies.

MATERIALS AND METHODS

Pure transgastric peritoneoscopy was performed in 7 pigs. The pigs were randomized to 14 or 28 postoperative days (POD) of follow-up. Decontamination of the access route was performed before instrumentation. A full necropsy was performed. Closure was evaluated with histopathological examination of excised gastrorrhaphies.

RESULTS

Three pigs were allowed 14 POD of follow-up, and 4 pigs were allowed 28 POD of follow-up. Survival was achieved in 6 of the 7 animals; 1 pig was euthanized due to diffuse peritonitis. Based on our definition, full-thickness healing had only been achieved in a single pig allowed 28 POD. With respect to clinical relevancy, full-thickness healing was deemed achieved in 4 of 6 pigs completing follow-up and in all pigs allowed and surviving 28 POD. Access required repeated punctures and the use of several endoscopic instruments.

CONCLUSIONS

Full-thickness healing of the gastrotomy was only found in a single case when adhering to the per protocol definition. Endoscopic ultrasonography-guided access was difficult. It lacks reproducibility and needs refinement. Despite a combined decontamination regimen, infectious complications still occurred.

Prospective randomized comparison of gastrotomy closure associating tunnel access and over-the-scope clip (OTSC) with two other methods in an experimental ex vivo setting

BACKGROUND

Safe transgastric natural orifice transluminal endoscopic surgery (NOTES) procedures require a reliable closure of the gastrotomy. Recently a novel peritoneal access method via a submucosal tunnel has been described with encouraging preliminary results.

AIM

The aim is to compare a submucosal tunnel access plus over-the-scope clip (OTSC) system for closure with two other closure modalities.

PATIENTS AND METHODS

This is a prospective ex vivo study conducted on 42 porcine stomach models equally randomized into three groups in an academic medical center. The procedures performed in each group included: (1) Tunnel (6 cm) + endoclips; (2) Knife + balloon dilation access + OTSC; and (3) Tunnel + OTSC. A pressurized air-leak test was performed to evaluate the strength of the closure. Stomach volumes, procedure times, number of clips, and incision sizes were also registered.

RESULTS

The mean air-leak pressure was statistically higher in Group 3 than in Groups 1 and 2-95.2 ± 19.3 mmHg versus 72.5 ± 35.2 and 79.0 ± 24.5 mmHg (P < 0.05). The gastrotomy creation times for Groups 1, 2, and 3 were 28.0 ± 10.1, 4.3 ± 1.4, and 20.1 ± 10.6 minutes, respectively, with significantly lower time in Group 2 (P < 0.001). The closure times were 16.1 ± 6.1, 6.5 ± 1.2, and 5.3 ± 3.0 minutes, respectively, and significantly longer in the endoclip group (P < 0.001). There were no differences in the volumes and the incision sizes among the three groups.

CONCLUSION

The combination of a submucosal tunnel access and OTSC offers a stronger closure than the other methods studied.

Endoscopic clip closure of gastrointestinal perforations, fistulae, and leaks

Development of endoscopic devices to close perforations has certainly revolutionized endoscopy. Immediate closure of perforations eliminates the need for surgery, which allows us to push the limits of endoscopic surgery from the mucosal plane to deep submucosal layers and eventually transmurally. The present article focuses on endoscopic closure devices, closure techniques, followed by a review of animal and clinical studies on endoscopic closure of perforations.

Performance of the OTSC System in the endoscopic closure of iatrogenic gastrointestinal perforations: a systematic review

BACKGROUND

Reliable closure is a prerequisite for conventional and innovative endoscopic procedures, such as NOTES. The purpose of this study is the systematic evaluation of the procedural and clinical success rates in closure of iatrogenic gastrointestinal perforations and acute anastomotic leaks by means of the over-the-scope-clip system (OTSC(®)).

DESIGN

PubMed and other sources were searched systematically for clinical and preclinical research on the evaluation of the OTSC System for closure of gastrointestinal perforations and leaks. Appraisal of studies for inclusion and data extraction was performed independently by two reviewers using an a priori determined data extraction grid. Major endpoints to be extracted were data on procedural success (successful clip application) and clinical access (durable closure of defect without secondary adjunct therapy).

RESULTS

A total of 17 clinical research articles/abstracts and 22 preclinical research articles/abstracts were identified. The examined clinical studies comprised case series and clinical single-arm studies. The reviewed studies revealed a consistently high mean rate of procedural success of 80-100 % and durable clinical success of 57-100 %. An identified major drawback preventing successful clip application was occurrence of fibrotic or inflamed lesion edges. Usage of the OTSC System was accompanied by neither major clip-related nor application-related complication. In experimental settings, closure of larger perforations and gastric access sites of NOTES or endoscopic full-thickness resection were achieved with high rates of success.

CONCLUSIONS

Because randomized, clinical trials are not available in this field of indication, the evaluation is based on small case series. Nevertheless, by pooling all experience gained, we conclude that endoscopic closure of iatrogenic gastrointestinal perforations and acute anastomotic leaks by means of the OTSC System is a safe and effective method.