Derek G. Fong

Transluminal closure for NOTES: an ex vivo study comparing leak pressures of various gastrotomy and colotomy closure modalities.

BACKGROUND AND STUDY AIMS Transluminal closure is fundamental to the safe introduction of natural orifice transluminal endoscopic surgery (NOTES) into humans. Suture, staples, and clips have been used. We aimed to evaluate the acute strength of various gastrotomy and colotomy closure techniques in an ex vivo porcine model by assessing air leak pressures. PATIENTS AND METHODS The following closure modalities were assessed with at least five samples per arm: conventional open/laparoscopic suturing techniques including full-thickness interrupted sutures, double-layer sutures, and purse-string sutures, as well as endoscopic clips and endoscopic staples. Historical values for transgastric closures with hand-sewn interrupted sutures, endoscopic clips, and a prototype endoscopic suture device were used from our laboratorys prior study. RESULTS Using Kruskal-Wallis analysis, the overall comparisons were significant ( P = 0.0038 for gastrotomy closure; P = 0.0018 for colotomy closure). Post hoc paired comparisons revealed that the difference between all closure arms versus negative control were significant. Significance could not be established among the various closure arms. However, trends suggested hand-sewn double-layer sutures, endoscopic staples, and both hand-sewn and endoscopically-placed purse-string sutures produced the strongest closures. Furthermore, endoscopic clips appeared sufficient for colotomy closure when ideally placed. CONCLUSIONS Suture (both hand-sewn and endoscopically deployed) appears to produce the strongest closures in both stomach and colon, with the important caveats that (1) a continuous through-thickness suture track be avoided, such as in the full-thickness closure, or (2) suture holes be buried, such as in the purse-string configuration. When suture tracks are full-thickness, they can serve as leak sites. Staples and clips can produce comparable closures, but only under ideal conditions.

Evaluation of a novel access and closure device for NOTES applications: a transcolonic survival study in the porcine model (with video)

BACKGROUND Natural orifice transluminal endoscopic surgery (NOTES) is a novel, potentially less invasive alternative to laparoscopic surgery. However, the problems of transluminal access and closure represent significant obstacles to its successful introduction in humans. OBJECTIVE Our purpose was to evaluate the feasibility and safety of a novel device designed for transluminal access and closure. DESIGN Experimental endoscopic study of transcolonic incision and closure with use of a prototype device in a survival porcine model. SUBJECTS Four adult female Yorkshire pigs were used in the study. INTERVENTIONS While under general anesthesia, the animals were prepped with multiple tap water enemas followed by instillation of an antibiotic suspension and povidone-iodine lavage. At a distance of 15 to 20 cm from the anus, the prototype device deployed a circumscribing purse-string suture around the planned incision site and subsequently used a blade mechanism to create a 2.5-cm linear incision. The peritoneum was then accessed with a standard double-channel enodoscope. The transcolonic incision was then closed by cinching and securing the purse-string suture with a titanium knot by use of a separate hand-activated suture-locking device. All animals were allowed to eat immediately after recovering from general anesthesia. MAIN OUTCOME MEASUREMENTS The animals were monitored daily for signs of peritonitis and sepsis and were electively killed on day 14. The peritoneal cavity was examined for peritonitis, and the colonic incision site was examined for wound dehiscence, pericolic abscess formation, and gross adhesions. Tissue samples from both incisional and random peritoneal sites were obtained for histologic examination. RESULTS Transcolonic incision and closure were successful in all 4 animals. The device performed in a rapid and reproducible fashion. All animals recovered without septic complications. At necropsy, there was no evidence of peritonitis, abscesses, or wound dehiscence. Salpingocolonic and colovesicular adhesions were noted in 3 of 4 animals. Histologic examination revealed microabscesses at the incision site in all animals. CONCLUSIONS The prototype incision and closure device represents a promising solution to the problems of transluminal access for NOTES. The presence of incision-related adhesions and microabscesses signal the need for further refinement in aseptic technique.