Introduction: Several studies have shown that the Self-Approximating Translumenal Access Technique (STAT) allows safe abdominal access and a reliable means of gastric closure for per-oral NOTES. Little is known, however, about the durability of the STAT tunnel under the mechanical forces required for organ resection and specimen retrieval. We hypothesized that simple extirpative abdominal operations (including specimen resection and retrieval) could be performed via STAT so that the tunnel would maintain its integrity for the conclusion of the procedure, permitting a secure gastrotomy closure.
Methods: 14 domestic swine (mean wt 26kg) underwent transgastric organ resection (7 cholecystectomy, 7 left uterine horn resection). Abdominal access was obtained using STAT (as previously described) with the submucosal tunnel directed at the target organ. The resected surgical specimen, a fully inflated 2 cm endoscopic balloon and an 8x3x3cm manufactured ‘standard specimen’ (a simulated human gallbladder with large gallstone) were sequentially retrieved through the submucosal tunnel. Evaluation of tunnel integrity and an assessment of the ease of specimen extraction were performed following each retrieval. Physiologic, operative and clinical data were collected. All procedures were video recorded. After a two-week observation period, animals were euthanized and necropsy performed for documentation of gross findings.
Results: The mean operative time was 4.1h (range 2.4-5.5hr). The mean abdominal access time (mucosal incision to serotomy) was 51min (range 26-78). A mean tunnel length of 12cm (6-23cm) with a width 4cm (2.5-5cm) was created. The STAT tunnel remained fully intact in: 14/14 after organ resection and retrieval, 13/13 after balloon extraction and 11/14 after standard specimen extraction. All three tears occurred early in our experience. Two small mucosal tears still permitted the STAT tunnel to be closed by standard endoscopic clip technique. One significant gastric tear required a single laparoscopic suture for secure closure. The ease in specimen extractions can be seen in Table 1. None of the standard specimens were able to be endoscopically delivered past the gastro-esophageal junction (GEJ). Post-operatively all animals gained weight. One animal, sacrificed at post-operative day 12 due to lethargy, had a cystic duct leak and biloma. Other necropsy findings included: adhesions (4), bile leak (1), laparoscopic port site abscess (1), small submucosal abscess(1).
4 (Early Cases)
Conclusions: The submucosal tunnel created using STAT is capable of withstanding the mechanical forces of transgastric organ resection and retrieval. STAT also permitted the removal of rigid specimens (simulate large gallstone). None of these standard specimens could be delivered past the GEJ, suggesting that tunneling methods of transgastric access are not the size-limiting factor in per-oral specimen retrieval. One significant mucosal tear occurred early in the study, suggesting that there is a learning curve inherent in making the STAT tunnel wide enough to accommodate large, rigid specimens.
Session: Podium Presentation
Program Number: S068