Peroral transgastric organ resection: a feasibility study in pigs

Current endoscopic closure techniques for the management of gastrointestinal perforations

Acute gastrointestinal perforations occur either from spontaneous or iatrogenic causes. However, particular attention should be made in acute iatrogenic perforations as timely diagnosis and endoscopic closure prevent morbidity and mortality. With the increasing use of diagnostic endoscopy and advances in therapeutic endoscopy worldwide, the endoscopist must be able to recognize and manage perforations. Depending on the size and location of the defect, a variety of endoscopic clips, stents, and suturing devices are available. This review aims to prepare and guide the endoscopist to use the right tools and techniques for optimal patient outcomes.

The application of a vascular closure device for closing a gastrostomy opening used for procedural access

OBJECTIVE

To study the feasibility of applying the Perclose ProGlide vascular closure device (PPVCD) in vitro for closing a gastrostomy opening for procedural access in the swine stomach in order to prevent peritoneal leakage.

METHODS

The study included four experimental groups: one manual suture (n = 10), two manual sutures (n = 10), one PPVCD suture (n = 10), and two PPVCD sutures (n = 5). In the two PPVCD sutures group, the "pre-close" technique was used. The leak pressure was measured, and statistical analysis was conducted to compare the leak pressures among the experimental groups.

RESULTS

The gastrostomy openings were successfully closed in all experimental groups. The median (range) values of leak pressure (mmHg) for each experimental group were as follows: one manual suture, 86.0 (75.0-110.0); two manual sutures, 98.5 (44.0-130.0); one PPVCD suture, 96.5 (56.0-119.0); and two PPVCD sutures, 98.0 (66.0-104.0). The Mann-Whitney U test revealed no statistically significant difference in leak pressure between the manual (n = 20) and PPVCD (n = 15) suture groups. The Kruskal-Wallis test revealed no statistically significant difference in leak pressure among the four experimental groups. The Bonferroni post hoc test also revealed no statistically significant difference in the pairwise comparisons among the groups.

CONCLUSION

Application of PPVCD is feasible for the closure of gastrostomy openings in an animal model and is as effective as a manual suture.

ADVANCES IN KNOWLEDGE

In our in vitro study, percutaneous closure of gastrostomy opening using PPVCD was possible; animal survival studies and development of specific devices are needed before clinical application.

Endoscopic closure after intraluminal surgery

Endoscopic submucosal dissection is established as a curative endoscopic method for gastrointestinal epithelial neoplasms with a high possibility of complete en bloc resection; however, postoperative adverse events of bleeding and delayed perforation remain. To prevent or minimize them, several techniques for endoscopic mucosal closure have been introduced, such as using endoscopic clips, combined use of hemoclips and supplement devices, and specially designed endoscopic suturing devices. Furthermore, endoscopic full-thickness suturing technique for gastrointestinal wall defect has been developed based on the concept in natural orifice transluminal endoscopic surgery and endoscopic full-thickness resection. Several closure techniques, including over-the-scope clip, threaded bars inserted in a hollow needle, stitches or staplers, and a curved needle and thread are reported. Secure closure of the iatrogenic defect may further expand the range of therapeutic endoscopy. Accumulation of evidence for the efficacy of endoscopic closure and establishment of these techniques are desired.

Asian perspectives in thoracic surgery: clinical innovation in Taiwan

The development of minimally-invasive surgery of the thorax began in the 1990s, but not until the recent decade did we see dramatic improvements in patient care and refinement of technique. The current generation has witnessed the evolution from traditional thoracotomy, to a single-port, non-intubated thoracoscopic approach. The investigation of subxiphoid single-port, transumbilical approach, and natural orifice transluminal endoscopic surgery (NOTES) in animal model are also undergoing. In Taiwan, several talented young surgeons have vigorously devoted their ideas and innovations to this field, making the Taiwan surgical society vivid and prosperous. The desire to improve, and willingness to change are the foundation of those surgeons. Providing better patient care is their impetus to strive for improvement. This article provides an account of how minimally-invasive thoracic surgery has evolved in recent years, and what clinical innovations have been developed by the Taiwan surgical society.

Endoscopic Suturing, an Essential Enabling Technology for New NOTES Interventions

Natural orifice transluminal endoscopic surgery (NOTES) was developed as a new, minimally invasive approach for various interventions inside the peritoneal cavity. Since the first reports of NOTES animal interventions, various devices have been used for closure of the transluminal entrance site. This article reviews the most commonly used endoscopic closure devices and advantages of the latest generation of endoscopic suturing devices enabling reliable, surgical-quality closure of the full-thickness gastrointestinal wall defects.

Shifting Paradigms in Minimally Invasive Surgery: Applications of Transanal Natural Orifice Transluminal Endoscopic Surgery in Colorectal Surgery

Since the advent of laparoscopy, minimally invasive techniques such as single port laparoscopy, robotics, endoscopically assisted laparoscopy, and transanal endoscopic surgery continue to revolutionize the field of colorectal surgery. Transanal natural orifice transluminal endoscopic surgery (NOTES) represents a further paradigm shift by combining the advantages of these earlier techniques to reduce the size and number of abdominal incisions and potentially optimize rectal dissection, especially with respect to performance of an oncologically adequate total mesorectal excision (TME) for rectal cancer. Since the first experimental report of transanal rectosigmoid resection in 2007, the potential impact of transanal NOTES in colorectal surgery has been extensively investigated in experimental models and recently transitioned to clinical application. There have been 14 clinical trials of transanal TME (taTME) for rectal cancer that have demonstrated the feasibility and preliminary oncologic safety of this approach in carefully selected patients, with results comparable to outcomes after laparoscopic and open TME, including cumulative intraoperative and postoperative complication rates of 5.5 and 35.5%, respectively, 97.3% rate of complete or near-complete specimens, and 93.6% rate of negative margins. Transanal NOTES has also been safely applied to proctectomy and colectomy for benign indications. The consensus among published series suggests that taTME is most safely performed with transabdominal assistance by surgeons experienced with laparoscopic TME, transanal endoscopic surgery, and sphincter-preserving techniques including intersphincteric resection. Future applications of transanal NOTES may include evolution to a pure endoscopic transanal approach for TME, colectomy, and sentinel lymph node biopsy for rectal cancer, with a potential role for robotic assistance.

Endoscopic closure of acute perforations of the GI tract: a systematic review of the literature

BACKGROUND

Surgical repair of endoscopic perforations of the GI tract used to be the standard, but immediate, secure endoscopic closure has become an attractive alternative treatment with the potential to reduce morbidity and mortality.

OBJECTIVE

We aimed to perform a systematic review of the medical literature on endoscopic closure of acute iatrogenic perforations of the GI tract.

DESIGN

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines.

SETTING

Available medical literature from 1966 through November 2013.

PATIENTS

Patients with an acute perforation after an endoscopic procedure that was closed endoscopically.

INTERVENTIONS

Endoscopic closure of an acute perforation of the GI tract.

MAIN OUTCOME MEASUREMENTS

Clinically successful endoscopic closure.

RESULTS

In our search, we identified 726 studies, 702 of which had to be excluded. Twenty-four cohort studies (21 retrospective, 3 prospective) were included in the analysis. No randomized trials were identified. Overall, the methodological quality was low. The 24 studies included described 466 acute perforations in which endoscopic closure was attempted. Successful endoscopic closure was achieved in 419 cases (89.9%; 95% CI, 87%-93%). Successful closure was achieved in 90.2% (n = 359; 95% CI, 87%-93%) of cases by using endoclips, in 87.8% (n = 58; 95% CI, 78%-95%) by using the over-the-scope-clip, and in 100% (n = 2) by using a metal stent.

LIMITATIONS

Low methodological quality of included studies.

CONCLUSION

This systematic review suggests that endoscopic perforation closure is a safe and effective alternative for surgical intervention in selected cases; however, the overall methodological quality was low. Prospective, true consecutive studies are needed to define the definitive role of endoscopic closure of perforations.

Total laparoscopic modified Duhamel operation in combination with transanal endoscopic microsurgery

INTRODUCTION

Laparoscopic-assisted colonic resection has been well described for multiple surgical indications and typically requires an abdominal incision for specimen removal that is associated with most of the postoperative pain. We report the total laparoscopic modified Duhamel operation for megacolon in combination with transanal endoscopic microsurgery for transanal specimen retrieval and anastomosis to avoid the additional abdominal extraction incision.

CASE DESCRIPTION

Two cases are presented: case 1 was a 15-year-old boy who presented with intermittent abdominal distention, pain, and constipation for 3 years' duration and was diagnosed with Hirschsprung disease, and case 2 was a 60-year-old man who presented with repeated attacks of incomplete intestinal obstruction for 2 years' duration and was diagnosed with adult megacolon. They were treated by the total laparoscopic modified Duhamel operation without an abdominal extraction incision in combination with transanal endoscopic microsurgery. The operations were successfully accomplished without conversion to open surgery. The patients tolerated the procedure well, complained of minimal postoperative pain, and did not require narcotics beyond the day of the operation. No surgical complications occurred. Discharge from the hospital occurred on the ninth postoperative day in case 1 and the 13th postoperative day in case 2.

DISCUSSION

The total laparoscopic modified Duhamel operation in combination with transanal endoscopic microsurgery is a feasible and minimally invasive technique for idiopathic megacolon and adult megacolon. This advanced surgical technique was developed by combining laparoscopy with the concept of natural orifice transluminal endoscopic surgery.

A novel, new robotic platform for natural orifice distal pancreatectomy

Laparoendoscopic technology has revolutionized the practice of surgery; however, surgeons have not widely accepted laparoscopic techniques for pancreatic surgeries due to the complexity of the operation. Natural orifice transluminal endoscopic surgery (NOTES) offers a great new potential for pancreatic procedures, with early data showing benefits of reduced visible scarring and the potential for decreased wound infections, hernias, pain, and postoperative complications. However, there are significant limitations to the currently used flexible endoscopy tools, including a diminished visual field, spatial orientation and tissue manipulation issues, and 2-dimensional visual feedback. We have adopted a novel snake-like robot, the minimally invasive cardiac surgery (MICS) robot, which addresses these issues. In the current pilot study, the MICS robot was evaluated for transrectal distal pancreas exploration and resection in 2 nonsurvival porcine models. Abdominal navigation and accessing the pancreas was investigated in the first pig, and based on its success, pancreas resection was studied in pig 2. The MICS robot was successful in accessing and visualizing the right upper, left upper, and left lower quadrants of the abdomen in pig 1 and was able to perform a successful complex NOTES procedure with distal pancreas resection in pig 2, with only minimal laparoscopic retraction assistance. In conclusion, preliminary results showing the MICS robot in natural orifice distal pancreatectomy are positive. Enhancements to optics and instrumentation will help further increase the usability in pancreatic interventions. Future indications may include transgastric NOTES approaches, endoluminal procedures, and single-port applications.

Forward-viewing endoscopic ultrasound-guided NOTES interventions: A study on peritoneoscopic potential

AIM: To evaluate the feasibility of diagnostic and therapeutic transgastric (TG) peritoneoscopic interventions with a forward-viewing endoscopic ultrasound (FV-EUS).

METHODS: This prospective endoscopic experimental study used an animal model. Combined TG peritoneoscopic interventions and EUS examination of the intra-abdominal organs were performed using an FV-EUS on 10 animal models (1 porcine and 9 canine). The procedures carried out include EUS evaluation and endoscopic biopsy of intraperitoneal organs, EUS-guided fine needle aspiration (EUS-FNA), EUS-guided radiofrequency ablation (EUS-RFA), and argon plasma coagulation (APC) for hemostatic control. The animals were kept alive for 7 d, and then necropsy was performed to evaluate results and complications.

RESULTS: In all 10 animals, TG peritoneoscopy, followed by endoscopic biopsy for the liver, spleen, abdominal wall, and omentum, was performed successfully. APC helped control minor bleeding. Visualization of intra-abdominal solid organs with real-time EUS was accomplished with ease. Intraperitoneal EUS-FNA was successfully performed on the liver, spleen, and kidney. Similarly, a successful outcome was achieved with EUS-RFA of the hepatic parenchyma. No adverse events were recorded during the study.

CONCLUSION: Peritoneoscopic natural orifice transluminal endoscopic surgery (NOTES) interventions through FV-EUS were feasible in providing evaluation and performing endoscopic procedures. It promises potential as a platform for future EUS-based NOTES.

Endoscopic closure of experimental iatrogenic gastric fundus perforation using over-the-scope clips in a surviving canine model

BACKGROUND AND AIM

To evaluate the effectiveness and outcomes of endoscopic closure of a gastric fundus perforation using over-the-scope clips (OTSCs) system in a surviving canine model.

METHODS

Gastric fundus perforations (20-mm diameter) were created by an endoscopic needle-knife in six dogs. The perforations then were closed by the OTSC system. Gastroscopy was performed to evaluate the postoperative perforation healing every week. The animals were sacrificed 4 weeks later to examine the possible intraperitoneal complications, and the healing of the perforation was examined histopathologically.

RESULTS

The gastric fundus perforations could primarily be closed using one OTSC in each experimental dog, and the mean time of the procedure was 17.3 ± 7.6 min (9-26 min). All animals survived without postoperative complications. The OTSC retention was observed in one dog at the end of 4 weeks, and the apparent foreign-body reaction was examined pathologically.

CONCLUSIONS

Our surviving animal study demonstrated that the OTSC clip system could reliably close gastric fundus perforations without complications.

NOTES for the management of an intra-abdominal abscess: transcolonic peritonoscopy and abscess drainage in a canine model

BACKGROUND

We studied natural orifice transcolonic drainage of intra-abdominal abscesses in a canine survival model to evaluate the difficulty of peritonoscopy and abscess drainage and the reliability of endoluminal colotomy closure.

METHODS

We placed a 7 cm nonsterile saline-filled latex balloon intra-abdominally to mimic or induce an abscess or inflammatory mass. Seven days later, we advanced a single-channel endoscope transanally into the sigmoid colon of the animal, made a colotomy and then advanced the endoscope intraperitoneally. We evacuated the identified abscess and placed a drain transabdominally. We closed the colotomy endoluminally with a tissue approximation system using 2 polypropylene sutures attached to metal T-bars. Two weeks later, we evaluated the colotomy closure at laparotomy.

RESULTS

We studied 12 dogs: 8 had subphrenic balloon implants and 4 had interbowel loop implants. Eleven survived and underwent transcolonic peritonoscopy; we identified the "abscess" in 9. The colotomy was successfully closed in 10 of 11 dogs. Although abscesses were easily identified, the overall difficulty of the peritonoscopy was moderate to severe. One dog required colotomy closure via laparotomy, while 9 had successful endoluminal closure. After colotomy closure, 8 animals survived for 2 weeks (study end point) without surgical complications, sepsis or localized abdominal infections. On postmortem examination, all closures were intact without any adjacent organ damage or procedure-related complications.

CONCLUSION

Natural orifice transluminal endoscopic surgery provides a novel alternative to treating intra-abdominal pathology. It is technically feasible to perform endoscopic transcolonic peritonoscopy and drainage of an intra-abdominal abscess with reliable closure of the colotomy in a canine experimental model.

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.

Endoscopic knot tying: In vitro assessment in a porcine stomach model

AIM: To determine if surgical knotting performed via endoscopy is an effective closure method for natural orifice translumenal endoscopic surgery.

METHODS: The proposed method was tested on an in vitro pig stomach model using standard endoscopy suite materials. A single use laparoscopy trocar (Versaport Plus manufactured by Tyco Healthcare) was fixed onto a plastic rectangular box in a horizontal position. A fresh pig stomach was tightly attached via its esophageal end to the trocar opening on the inner side of the box. The stomach cavity was closed at the duodenal end with Kocher forceps. A standard upper gastrointestinal endoscope fitted at its tip with a transparent plastic cap was introduced into the stomach through the outer trocar opening, so that the passage of the surgical trocar would mimic the passage of an esophagus. The stomach was subsequently inflated, followed by irrigation and washing. A neutral electrode of an electrocautery unit was placed inside the plastic box, underneath the pig stomach. The stomach’s outer surface was kept moist using normal saline in order to maintain the natural elasticity and to ensure good contact with the electrode.

RESULTS: The submucosal space on the anterior face of the stomach was accessed using the technique of endoscopic submucosal dissection. First, a site on the anterior face of the stomach was chosen, near the angle. Then, saline was injected into the submucosa with a standard endoscopic needle, so as to create a 20 mm diameter elevation. A linear 15 mm vertical incision was created at its center using a Dual Knife (KD650U manufactured by Olympus). This incision was used to access the submucosal space, and about 10 mm was dissected on both sides of the incision. The endoscope was then pushed through to the outside of the stomach after dilating a small puncture made by the Dual Knife in the muscularis propria, which simulated the peritoneoscopy procedure. Then, a 0.025” guidewire (Jagwire/450 cm manufactured by Boston Scientific) was inserted into the puncture, followed by a dilating balloon (Quantum TT manufactured by Cook Medical) that was used to enlarge the aperture orifice. After withdrawing the scope back into the stomach, the procedure continued with guidewires being passed from the submucosal space into the gastric lumen through small orifices on the left and right sides of the mucosal opening. These orifices were made with the Dual Knife, and the guidewires were inserted via a guiding catheter (HGC-6 manufactured by Cook Medical). As the guidewires were pulled outside of the stomach, they were replaced with a single surgical suture that had been initially attached to their tip and was now untied. Finally, one loop of this surgical suture was formed on the exterior. One loop end was fixed while the opposite suture end was pulled by biopsy forceps through the endoscope channel as the scope was inserted into the stomach. The loop was advanced until it approached and fixed the two mucosal incision margins. Three alternating loops were made in this manner to create a genuine tight surgical knot.

CONCLUSION: Endoscopic knotting of the gastric wall is feasible, but an in vitro survival study is necessary to validate clinical significance.

Laparoscopic assisted transvaginal cholecystectomy: single centre preliminary experience

BACKGROUND

Natural Orifice Transluminal Endoscopic Surgery (NOTES) is a new approach that allows abdominal surgery to be performed through a natural orifice such as the oral cavity, vagina or rectum. We present our preliminary experience of laparoscopic assisted transvaginal cholecystectomy (LATC).

METHODS

Women affected by cholelithiasis, age below 65 years, BMI under 30, ASA I or II, previous full-term pregnancies, and without previous abdominal surgery underwent LATC. Patients' biographic data, operative time, intraoperative and postoperative complications were collected.

RESULTS

We performed 21 LATCs. Median operative time was 58 min. There were no intraoperative complications. The postoperative course was uneventful in all patients. At 1 year there were no complications and no impaired sexual activity.

CONCLUSIONS

The results of NOTES are promising, but currently only hybrid NOTES can be safely performed. LATC seems to guarantee better cosmetic results, less postoperative pain, faster mobilization and shorter hospitalization than laparoscopic cholecystectomy.

Total laparoscopic sigmoid and rectal surgery in combination with transanal endoscopic microsurgery: a preliminary evaluation in China

BACKGROUND

This study was designed to evaluate the feasibility and safety of total laparoscopic sigmoid and rectal surgery without abdominal incision in combination with transanal endoscopic microsurgery (TEM).

METHODS

From May 2010 to October 2011, 34 patients with colon and rectal tumors were treated by total laparoscopic surgery without abdominal incision, and the clinical data of these patients were reviewed.

RESULTS

All operations could be successfully accomplished without conversion to open surgery. No diverting ileostomy was created. The average operative time was 151.60 (range, 125-185) minutes. The average blood loss was 200.20 (range, 55-450) ml. All resection margins were negative. Six patients developed postoperative anastomotic leakage. There were no reports of other complications in all patients.

CONCLUSIONS

This preliminary study indicated that total laparoscopic sigmoid and rectal surgery in combination with TEM was a safe, feasible, and minimally invasive technique. This advanced surgical technique was developed by combining laparoscopy with the concept of natural orifice transluminal endoscopic surgery.

Feasibility study of secure closure of gastric fundus perforation using over-the-scope clips in a dog model

BACKGROUND AND AIM

Gastric fundus perforation is a serious complication of endoscopic mucosal resection and endoscopic submucosal dissection performed for the removal of early gastric cancers or subepithelial tumors. The novel over-the-scope clip (OTSC) has recently been found to be effective for closing gastrointestinal-tract perforations and accesses for natural orifice transluminal endoscopic surgery. However, feasibility studies of OTSCs in gastric fundus perforation are still lacking. The aim of this study was therefore to demonstrate the feasibility of endoscopic closure of gastric fundus perforation using the OTSC system in a dog model.

METHODS

Gastric fundus perforations were created by needle-knife electrocautery in seven dogs. The perforations were then closed using the OTSC clipping system. Stomach distension was maintained by maximum insufflation with air and methylene blue solution (500 mL) was instilled to submerge the closed perforation. Leaks were detected laparoscopically.

RESULTS

Perforations were closed in all seven cases with a mean time of 18.5 ± 6.4 min (11-28 min). Twin Grasper assistance failed to release the OTSCs in two of the seven cases (2/7, 28.6%) because of difficulties associated with the J-maneuver (retroflexion of endoscope) required for the gastric fundus procedure, and OTCS were forced into place by suction. Minor leakage was observed in one case (1/7, 14.3%). No damages related to the clip system were found during postmortem examinations.

CONCLUSIONS

Despite difficulties associated with the J-maneuver of the endoscope, this small series demonstrated that sufficient closure of gastric fundus perforation could be achieved using the OTSC system.

Natural orifice translumenal endoscopic surgery in humans: a review

Natural orifice translumenal endoscopic surgery (NOTES) had its origins in numerous small animal studies primarily examining safety and feasibility. In human trials, safety and feasibility remain at the forefront; however, additional logistic, practical, and regulatory requirements must be addressed. The purpose of this paper is to evaluate and summarize published studies to date of NOTES in humans. The literature review was performed using PUBMED and MEDLINE databases. Articles published in human populations between 2007 and 2011 were evaluated. A review of this time period resulted in 48 studies describing procedures in 916 patients. Transcolonic and transvesicular procedures were excluded. The most common procedure was cholecystectomy (682, 75%). The most common approach was transvaginal (721, 79%). 424 procedures (46%) were pure NOTES and 491 (54%) were hybrid NOTES cases. 127 (14%) were performed in the United States of America and 789 (86%) were performed internationally. Since 2007, there has been major development in NOTES in human populations. A preponderance of published NOTES procedures were performed internationally. With further development, NOTES may make less invasive surgery available to a larger human population.

Efficacy of endoscopic closure of acute perforations of the gastrointestinal tract

BACKGROUND & AIMS

Acute perforations of the gastrointestinal tract are rare, severe complications of endoscopy that usually require surgical repair. Endoscopic repair of perforations would reduce the need for surgeries; we evaluated the efficacy and safety of endoscopic closure of acute perforations of the gastrointestinal tract by using a new clip device.

METHODS

We conducted a prospective, international, multicenter study of 36 consecutive patients (15 male) with acute iatrogenic perforations (5 esophageal, 6 gastric, 12 duodenal, and 13 colonic perforation). Endoscopic repair was performed by using the Over-the-Scope-Clip according to a standardized operating procedure. Primary end point was successful closure, which was determined as endoscopic successful closure without leakage (detected by water-soluble contrast x-ray analysis), and absence of adverse events within 30 days after the procedure.

RESULTS

Immediate closure was endoscopically successful in 33 patients (92%). One patient developed an esophageal perforation while the cap was introduced, and in 2 patients the perforations did not close; these 3 patients were successfully treated with surgery. None of the patients had leakage of soluble contrast on the basis of contrast x-ray. One patient with a closed colonic perforation deteriorated clinically within 6 hours after the procedure. Despite surgery, the patient died within 36 hours. The remaining 32 patients had successful endoluminal closures; the overall success rate was 89% (95% confidence interval, 75%-96%). The mean endoscopic closure time was 5 minutes 44 seconds ± 4 minutes 15 seconds.

CONCLUSIONS

The Over-the-Scope-Clip is effective for endoluminal closure of acute iatrogenic perforations. It allows patients to avoid surgery, and 89% of patients had successful closures without adverse events.

Current progress on natural orifice transluminal endoscopic surgery (NOTES)

Natural orifice transluminal endoscopic surgery (NOTES) has received considerable interest in recent years as a novel surgical technique. Here, we aim to review the current progress on NOTES, particularly focusing on the advantages and complications related to NOTES, the recent advances of surgical approaches, new instruments for closure of the natural orifice incision, and the newly developed platform for NOTES. Finally, we make a prediction of the conceivable applications of NOTES on human subjects.

Efficacy and safety of transgastric closure in natural orifice transluminal endoscopic surgery using the OTSC system and T-bar sutures: a survival study in a porcine model

BACKGROUND

In natural orifice transluminal endoscopic surgery (NOTES), procedures are performed with an endoscope passed through a natural orifice. One of the most important factors that will determine the future of transgastric NOTES is obtaining a reliable closure of the access site. The aim of this study was to determine the efficacy and safety of transgastric closure using the over-the-scope clip (OTSC) system or T-bar sutures.

METHODS

We performed a survival study that included 15 pigs. A standardized transgastric approach to the peritoneal cavity and a peritoneoscopy were performed. The gastrotomy was closed using the OTSC system or T-bar sutures. The gastrotomy closure was tested for leaks with the methylene blue test. All animals were observed for 2 weeks before they were sacrificed and necropsy was performed. Histopathological examination of tissue samples retrieved from the access sites was performed.

RESULTS

There were no perioperative complications. The methylene blue test did not demonstrate any leakage of fluid. Necropsy after 2 weeks confirmed completeness of gastric closure in all animals with full-thickness healing and no spillage of gastric contents into the peritoneal cavity. No differences between the OTSC system and T-bar sutures were observed.

CONCLUSION

We observed no differences between the efficacy and safety of the OTSC system and those of T-bar sutures used in closing gastric incisions in NOTES. Both methods are safe and effective.

Infection during natural orifice transluminal endoscopic surgery peritoneoscopy: a randomized comparative study in a survival porcine model

BACKGROUND

Infection in natural orifice transluminal endoscopic surgery (NOTES) remains controversial.

OBJECTIVE

To estimate the frequency of infection during NOTES peritoneoscopy with different routes of access and to compare with laparoscopy.

DESIGN

Prospective randomized controlled study (Canadian Classification type I).

METHODS

Forty female pigs were randomly assigned to 3 NOTES (transgastric, transrectal, and transvaginal) and laparoscopic groups. Antiseptic technique was used for NOTES, whereas laparoscopy was performed in a sterile environment. Preoperative and postoperative intravenous antibiotics were administered. Closure of the transluminal access site was performed in all animals. Peritoneal fluid was collected for culture at the end of surgery and at necropsy at day 14.

RESULTS

Thirty-nine peritoneoscopies were successfully completed. Necropsy confirmed complete healing of NOTES incisions, but 2 animals in the laparoscopy group had small abscesses in the abdominal incisions. There were no statistical differences in the presence of peritoneal adhesions. Positive culture results were seen in all groups at the end of the procedure and in all animals at necropsy, but this did not lead to clinical signs of gross infection. The most common organisms that colonized the peritoneum were gram-positive cocci and gram-negative bacilli from the normal swine gastrointestinal flora.

LIMITATIONS

Animal model and small sample size.

CONCLUSIONS

In these small series of animals and with the careful lavage and preparation used, NOTES appeared to be comparable to laparoscopy in terms of peritoneal contamination and clinical infection. Despite the adherence to a strict antiseptic protocol, peritoneal contamination occurs but does not lead to septic complications in the swine.

Intramural acellular porcine dermal matrix (APDM)-assisted gastrotomy closure for natural orifice transluminal endoscopic surgery (NOTES)

BACKGROUND

A highly reliable and safe means of gastric closure for natural orifice transluminal endoscopic surgery (NOTES) has yet to be developed. The authors have previously described the self-approximating transluminal access technique (STAT) as a means for gastrotomy closure in transgastric surgery. It has yet to be determined whether biologic mesh can be utilized in facilitating gastrotomy closure via STAT. The aim of this study was to determine the feasibility of implanting an acellular porcine dermal matrix (LifeCell) into the STAT tunnel and investigate whether it will become incorporated into the submucosal plane of the STAT tunnel.

METHODS

Five pigs underwent transgastric left uterine horn resection utilizing STAT. For closure, the acellular porcine dermal matrix was implanted within the submucosal plane, occluding the seromuscular incision. The mucosal incision was then closed over the matrix with endoscopically placed clips. Necropsy was performed after a 3 week survival period. Histopathological evaluation of the tunnel and matrix was performed.

RESULTS

The matrix was successfully implanted in all five animals. Average OR time was 151 ± 68 min. Average time to anchor and embed the matrix within the tunnel was 4 ± 1 and 9 ± 12 min, respectively. There was one duodenal perforation related to a balloon occlusion device. Postoperative course was unremarkable; the average weight gain at 3 weeks was 22 ± 5 lbs. On necropsy, one animal had some protrusion of the matrix at the serotomy, with adhesions to small bowel and liver. Histopathology revealed one clinically insignificant microabscess but otherwise demonstrated local inflammation and fibrovascular ingrowth into the matrix.

CONCLUSIONS

The porcine dermal matrix can be successfully implanted within the gastric submucosal plane and evidence of incorporation into the gastric wall by 3 weeks was demonstrated.

Pure natural orifice transluminal endoscopic surgery (NOTES) with ultrasonography-guided transgastric access and over-the-scope-clip closure: a porcine feasibility and survival study

BACKGROUND

Most natural orifice transluminal endoscopic surgery (NOTES) procedures to date rely on the hybrid technique with simultaneous laparoscopic access to protect against access-related complications and to achieve adequate triangulation for dissection. This is done at the cost of the potential benefits of this new minimally invasive technique. This study aimed to evaluate the feasibility and safety of a transgastric (TG) pure-NOTES procedure in a diagnostic setting.

METHODS

A TG pure-NOTES procedure with endoscopic ultrasonograpy (EUS)-guided access and over-the-scope-clip (OTSC) closure was performed for 10 pigs in a survival and feasibility study. A full macroscopic necropsy with subsequent histologic evaluation was performed on postoperative day (POD) 14. The outcome parameters were uncomplicated follow-up assessment, survival, intraoperative complications, intraabdominal pathology, macroscopic full-thickness closure, and histology-proven full-thickness healing of the gastrotomy.

RESULTS

An uncomplicated postoperative course was reported for 9 of the 10 pigs, and survival was reported for all 10 pigs. For all the pigs, EUS-guided access was performed successfully with a median duration of 25 min (range, 12-62 min) and without intraoperative complications or access-related lesions at necropsy. An OTSC closure was achieved with a median duration of 11 min (range, 3-28 min). The OTSC provided immediate closure, but according to the authors' definition of a full-thickness healing evaluated by histologic examination, this was not achieved in any of the cases. Although all the animals survived until POD 14, intraabdominal chronic abscesses were present in 3 of the 10 pigs at necropsy.

CONCLUSIONS

The EUS-guided TG access proved to be feasible without access-related complications. Although OTSC provided an immediate closure, the histopathology raised concerns regarding the risk of perforation. Together with the high risk of intraabdominal infection, TG pure-NOTES is not yet ready for routine clinical practice.

Transgastric pure-NOTES peritoneoscopy and endoscopic ultrasonography for staging of gastrointestinal cancers: a survival and feasibility study

BACKGROUND

Human natural orifice transluminal endoscopic surgery (NOTES) has mainly been based on simultaneous laparoscopic assistance (hybrid NOTES), forgoing the theoretical benefits of the NOTES technique. This is due to a lack of NOTES-specific instruments and endoscopes, making pure-NOTES procedures difficult and time consuming. An area where pure NOTES could be adopted at its present stage of development is minimally invasive staging of gastrointestinal (GI) cancer. The aim of this study is to evaluate the feasibility of combining transgastric (TG) pure-NOTES peritoneoscopy and intraperitoneal endoscopic ultrasonography (ip-EUS) with intraluminal EUS (il-EUS) for peritoneal evaluation.

METHODS

This was a feasibility and survival study where il-EUS followed by ip-EUS and peritoneoscopy was performed in 10 pigs subjected to TG pure NOTES. A score was given with regard to achieved visualisation of predefined anatomical structures. Survival was assessed at postoperative day (POD) 14.

RESULTS

All animals survived until POD 14. Median total procedural time was 94 min (range 74-130 min). Median time for il-EUS, ip-EUS and peritoneoscopy was 11 min (range 7-14 min), 13 min (range 8-20 min) and 10 min (range 6-23 min). Il-EUS, ip-EUS and peritoneoscopy resulted in a score of 15/15 points (range 14-15 points), 6/9 points (range 1-8 points) and 12/13 points (range 8-13 points).

CONCLUSIONS

TG pure-NOTES peritoneoscopy and ip-EUS combined with il-EUS is feasible and provides sufficient peritoneal evaluation. The technique could have potential for minimally invasive staging of GI cancers.

Natural orifice transluminal endoscopic surgery: New minimally invasive surgery come of age

Although in the past two decades, laparoscopic surgery, considered as a great revolution in the minimally invasive surgery field, has undergone major development worldwide, another dramatic surgical revolution has quietly appeared in recent years. Ever since Kalloo’s first report on transgastric peritoneoscopy in a porcine model in 2004, interest in a new surgical procedure named natural orifice transluminal endoscopic surgery (NOTES) has blossomed worldwide. Considering that a NOTES procedure could theoretically avoid any abdominal incision, operation-related pain and scarring, many surgeons and endoscopists have been enthusiastic in their study of this new technique. In recent years, several NOTES studies have been carried out on porcine models and even on humans, including transvaginal cholecystectomy, transgastric appendectomy, transvaginal appendectomy, and transvesical peritoneoscopy. So what is the current situation of NOTES and how many challenges do we still face? This review discusses the current research progress in NOTES.

Natural orifice transluminal endoscopic surgery (NOTES) in animals

Natural orifice transluminal endoscopic surgery (NOTES) is a modern technique of performing surgical procedures developed worldwide. In the last few years, series of NOTES operations were performed in animals and humans. This article describes some surgical procedures performed in animals with use of this new technique.

Natural orifice transluminal endoscopy surgery: A review

Minimally invasive surgery started spreading worldwide in 1987, when the first laparoscopic cholecystectomy was performed. Meanwhile, improvement of endoscopic equipment and instruments allowed gastroenterologists to attempt more aggressive endoluminal interventions, even beyond the wall barrier. The first transgastric peritoneoscopy, in 2004, brought to light the concept of natural orifice transluminal endoscopic surgery (NOTES). The idea of incisionless surgery is attractive and has become a new goal for both surgeons and other people interested in this field of investigation. The authors present a review of all developments concerning NOTES, including animal studies and human experience.

Gastrointestinal perforations: role of endoscopic closure

PURPOSE OF REVIEW

Understanding the role of endoscopic closure techniques helps in expanding the endoscopist's role in the management of gastrointestinal neoplasia and explore new frontiers of minimally invasive endoluminal surgery.

RECENT FINDINGS

This article covers recent advances in endoscopic closure of various gastrointestinal perforations, with a special focus on devices, experimental evidence and clinical outcomes of endoscopic closure of gastrointestinal perforations.

SUMMARY

Endoscopic closure techniques help the endoscopist to walk on thin ice and save himself and the patient in the case of mishap.

Transgastric endoscopic pneumoperitoneum versus laparoscopy: effects on host systemic and peritoneal inflammatory responses in a porcine model

BACKGROUND

The host systemic and peritoneal immune responses during natural orifice transluminal endoscopic surgery (NOTES) continues to be delineated. The immune response to laparoscopy (LAP) has been favorably depicted. However, the immunologic effects of NOTES are yet to be determined, and the introduction of contaminants via the host orificium may have deleterious effects. The purpose of this study was to characterize the effect that NOTES would have on porcine systemic and peritoneal immune function.

METHODS

Twenty-four pigs were divided into three groups: ENDO (upper-endoscopy control), NOTES, and LAP. All animals had blood and peritoneal lavage samples collected for cytokine analysis pre- and postoperatively. Interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-10 (IL-10), tumor necrosis factor α (TNFα), and interferon γ (IFNγ) levels were quantified using enzyme-linked immunosorbent assay (ELISA). Peritoneal lavage samples were cultured and identified by group and time of collection for microbiological analysis.

RESULTS

TNFα was found in detectable levels in serum samples of all three groups. For the NOTES group, there was a significant increase in TNFα at t = 1 h (P < 0.01), which dropped significantly at t = 48 h (P < 0.01). IL-1β was present as an early response in NOTES lavage samples (t = 0 and t = 1 h). Both LAP and NOTES had similar elevation of IL-1β in the final lavage samples at t = 48 h. The other cytokines were not consistently found above detectable levels in any group. Similar microbiological contaminants were found in the ENDO and LAP groups. In the NOTES group, no significant growth was observed from cultures at 48 h.

CONCLUSIONS

For measurable cytokines, the NOTES inflammatory response was not significantly different from that of the LAP group. NOTES did not carry a significantly increased amount of microbiological contamination at 48 h compared to LAP. These data suggest that the host immune response to NOTES does not significantly differ from that to LAP in a porcine model.

Enhancement of a Master-Slave Robotic System for Natural Orifice Transluminal Endoscopic Surgery

Introduction: A novel robotic platform for Natural Orifice Transluminal Endoscopic Surgery (NOTES) is presented in this paper. It aims to tackle two crucial technical barriers which hinder its smooth transition from animal studies to clinical trials: providing effective instrumentations to perform complex NOTES procedures and maintaining the spatial orientation for endoscopic navigation. Materials and Methods: The technical barriers are overcome by the design of the robotic system considering size, triangulation, dexterity, maneuverability and complexity. It is also shown that haptic feedback and interventional navigation system could solve the problem of off-axis manipulation of the camera angle and loss of spatial orientation upon entering the peritoneal cavity in transgastric NOTES procedure, respectively. Results: Successful ESD (endoscopic submucosal dissection) and wedge hepatic resection have been performed on live pigs with our Master And Slave Transluminal Endoscopic Robot (MASTER) system, showing its capability to perform advanced endoscopic surgical and NOTES procedures. It is found that the MASTER exhibited good grasping and cutting efficiency. And the lesion resection time could be significantly reduced with more practice between the endoscopist and the robot operator. Conclusion: This study evaluates the feasibility of MASTER system as a platform overcoming the barriers to NOTES. It is also demonstrated that the MASTER could effectively mitigate the technical constraints normally encountered in NOTES procedures. Key words: Haptic feedback, Instrumentation design, Interventional Navigation System (INS), Tracking

Initial experience from the transgastric endoscopic peritoneoscopy and biopsy: a stepwise approach from the laboratory to clinical application

BACKGROUND AND AIM

Natural-orifice translumenal endoscopic surgery (NOTES) is a newly minimally invasive technique that gives access to the abdominal cavity via transgastric, transcolonic, transvaginal or transvesical routes. The aim of the present study was to evaluate the safety and feasibility of transgastric endoscopic peritoneoscopy and biopsy from laboratory to clinical application.

METHODS

With the animals under general anesthesia, a sterile esophageal overtube was placed and a gastric antibiotic lavage was performed. Subsequently, a needle-knife and through-the-scope dilating balloon were used to make an anterior gastric wall incision through which a therapeutic gastroscope was advanced into the peritoneal cavity. After 2 weeks, another transgastric endoscopic exploration was performed in a different location of the stomach. The peritoneal cavity was examined before the gastric incision was closed. After 4 weeks of observation, necropsy was performed. In the clinical application, after gastric lavage, the first step was the creation of the gastrotomy under general anesthesia, sometime under direct vision of the laparoscopic scope. Then the endoscope can be maneuvered in the peritoneal cavity. And peritoneoscopy and biopsy were performed. Biopsies can be obtained from any suspicious areas using punch biopsy forceps. The gastrotomy was then closed with clips. The gastroscopy was examined after one week.

RESULTS

Twenty-eight transgastric endoscopic peritoneoscopies and biopsies in pigs and a total of five transgastric human endoscopic peritoneoscopies and biopsies have been performed. All procedures were completed satisfactorily in the pig model and all patients. There were no intraoperative or postoperative complications.

CONCLUSIONS

The advantages of peritoneoscopy and biopsy appeared to be enhanced by this approach. Patients had minor postoperative pain and minimal scarring. It is safe and feasible for us to use transgastric endoscopic peritoneoscopy and biopsy in humans.

Development of a pancreatic tumor animal model and evaluation of NOTES tumor enucleation

BACKGROUND

Laparoscopic distal pancreatectomy is associated with high morbidity and mortality. NOTES tumor enucleation may provide an alternative to laparoscopic distal pancreatectomy. The goal of this study was to determine the feasibility of NOTES tumor creation and enucleation as a multidisciplinary approach.

METHODS

A linear-array endoscopic ultrasound (EUS) endoscope was used to inject a thermosensitive ABA triblock polymer mixed with methylene blue through the stomach wall and into the distal pancreas using a 22-gauge EUS needle. Due to its thermosensitive character, the polymer solidifies in response to body temperature, creating an artificial tumor. Seventeen swine underwent NOTES transgastric pancreatic tumor enucleation. Nine nonsurvival animals were sacrificed immediately after the NOTES procedure, with subsequent necropsy. Eight survival animals were observed for up to 16 days after the procedure, subsequently sacrificed, followed by necropsy.

RESULTS

The procedure was performed successfully in all 17 pigs studied, 9/9 nonsurvival (100%) and 8/8 survival (100%) animals, using a pure NOTES approach without any laparoscopic ports. Complications included two esophageal dissections (1 in nonsurvival group, 1 in survival group) caused by the introduction of the endoscopic overtube (2/17, 12%), unrelated to the actual surgical procedure. In the survival animals, there were two small splenic lacerations caused during retraction with the endoscopic forceps, for which hemostasis was achieved prior to closure of the gastrotomy (2/7, 29%). At necropsy of the animals, there was sufficient closure of 15/17 gastrotomy sites (88%).

CONCLUSIONS

The creation of artificial pancreatic tumors via EUS guidance is feasible. Pancreatic tumor enucleation using a transgastric NOTES approach is technically feasible and could be an alternative to laparoscopic distal pancreatectomy with further development. Further adoption and adaptation of this technique will require the development of more sophisticated specialized tools to improve the safety profile of the procedure.

Gastrotomy closure with a new tissue anchoring device: A porcine survival study

AIM: To evaluate the feasibility, reproducibility and efficacy of a new tissue anchoring device in a porcine survival model.

METHODS: Gastrotomies were performed using a needle-knife and balloon dilator in 10 female Yorkshire pigs weighing 30-35 kg. Gastric closure was attempted using a new tissue anchoring device. The tightness of the closure was confirmed by means of air insufflation and the ability to maintain gastric distension with stability in peritoneal pressure measured with a Veress needle. All animals were monitored daily for signs of peritonitis and sepsis over 14 d. During necropsy, the peritoneal cavity and the gastric access site were examined.

RESULTS: Transgastric access, closure and 14 d survival was achieved in all pigs. The mean closure time was 18.1 ± 19.2 min and a mean of 2.1 ± 1 devices were used. Supplementary clips were necessary in 2 cases. The closure time was progressively reduced (24.8 ± 13.9 min in the first 5 pigs vs 11.4 ± 5.9 min in the last 5, P = NS). At necropsy, the gastric access site was correctly closed in all cases with all brace-bars present. One device was misplaced in the mesocolon. Minimal adhesions were observed in 3 pigs and signs of mild peritonitis and adhesions in one.

CONCLUSIONS: The use of this new tissue anchoring device in porcine stomachs is feasible, reproducible and effective and requires a short learning curve.

Gastrotomy closure with the lock-it system and the Padlock-G clip: a survival study in a porcine model

BACKGROUND AND STUDY AIMS

The success of natural orifice surgery depends on secure closure of the transmural gut opening, so a rapid, secure, and easy-to-place closure method is desirable. Our aim was to determine whether a gastrotomy can be closed safely and effectively from within the stomach in a survival model by using a novel, endoscopically placed device: the Padlock-G system.

PATIENTS AND METHODS

This was a pilot study of 4 survival animals in an animal laboratory setting. Gastrotomies were made in the stomachs of laboratory swine, and the abdomen was explored by using a standard gastroscope. Gastrotomies were then closed by using the Padlock-G system. Survival for 2 or 6 weeks was the primary outcome measurement. Secondary outcomes included ease of use, visual assessment of closure integrity immediately and at necropsy, presence of adhesions, evidence of infection, and histologic appearance at the closure sites.

RESULTS

All animals thrived, ate normally, and gained weight. None developed fever, tachycardia, or signs of peritoneal irritation. Closure-site inspection at necropsy revealed excellent healing, with epithelial growth over the Padlock-G. There were no ulcers, serosal surfaces were tightly closed, and no defects could be seen. There were no signs of peritoneal inflammation, intra-abdominal adhesions, or gastric spillage. Histologic evaluation showed organizing granulation tissue with fibrosis, vascular proliferation, and mild chronic inflammatory infiltrate (i.e., scar).

CONCLUSIONS

The Padlock-G is easy to place, provides a durable closure, and allows survival animals to thrive without adverse sequellae. This device provides a suitable closure system for transgastric NOTES.

Gastric lymphatic basin dissection for sentinel node biopsy using hybrid natural orifice transluminal endoscopic surgery (NOTES)

The aim of the present study was to describe a method of gastric lymphatic basin dissection for sentinel node biopsy using natural orifice transluminal endoscopic surgery with laparoscopic assistance (hybrid NOTES) in a porcine model. Lymph node dissection was performed in three healthy female domestic farm pigs (each around 40 kg) between October, 2007, and December, 2007. The pigs were administered a general anesthetic and laparoscopy-guided transvaginal colpotomy was performed. A two-channel endoscope was then inserted through the incision into the peritoneal cavity via the transvaginal route. An endoscope was inserted simultaneously into the mouth and indocyanine green solution was injected into the submucosal layer of the gastric wall at four sites. Dyed omentum and lymphatics were dissected using a laparoscopic dissector and the grasping forceps of a transvaginal endoscope. Lymphatics and omentum (mean 13.3 cm, range 8-20 cm) were removed transvaginally. The mean number of detected and resected sentinel nodes was 2.6 (range 1-4, diameter 2~12 mm). Sentinel lymphatic basin dissection was performed successfully and without intraoperative complications in all three cases. Hybrid NOTES is technically feasible, and this procedure may represent an alternative to laparoscopic sentinel lymph node dissection of the stomach.

Transvesical peritoneoscopy with rigid scope: feasibility study in human male cadaver

BACKGROUND

Transvesical port refers to the method of accessing the abdominal cavity through a natural orifice (i.e., urethra) under endoscopic visualization. Since its introduction in 2006, various reports have been published describing different surgical interventions using a rigid ureteroscope in a porcine model. The aim of this study was to test the access and feasibility of peritoneoscopy by using a rigid ureteroscope in a human male cadaver.

METHODS

Two adult male cadavers were used to perform the procedures. A rigid ureteroscope was used for the creation of transvesical access into the peritoneal cavity. Peritoneoscopy, liver biopsy, and identification and manipulation of the ileocecal appendix were performed.

RESULTS

Transvesical access into the peritoneal cavity was quickly established. The rigid ureteroscope easily allowed visualization of the abdominal cavity with good image quality. Liver biopsy and manipulation of ileocecal appendix were carried out without difficulties.

CONCLUSIONS

Peritoneoscopy, liver biopsy, and ileocecal appendix manipulation using a rigid ureteroscope through a transvesical port is feasible in a cadaver model. The development of a specific rigid scope for the transvesical port might herald a promising future for this NOTES access.

Endoscopic repair of small symptomatic gastrogastric fistulas after gastric bypass surgery: a single center experience

Gastrogastric fistula (GGF) is a known complication of gastric bypass surgery. Revisional surgery for GGF repair can be technically challenging. We describe our experience with endoscopic repair of small GGFs. A retrospective review was performed to identify patients in whom symptomatic GGF was repaired endoscopically at our institution between September 2004 and September 2008. At endoscopy, the fistulous margins were debrided using cold biopsy forceps or ablated using Argon Plasma Coagulation (APC). The fistula was then repaired with endoclips. Status of GGF repair was assessed intra-operatively, at 2 weeks by upper gastrointestinal (UGI) series, and at regular follow-up thereafter. GGF repair was attempted in eight female patients (mean age = 47 years). The average time interval between gastric bypass surgery and GGF presentation was 81 months. The presenting symptoms included nausea, vomiting, abdominal pain, and weight regain. The average duration of endoscopic procedure was 55 min. All GGFs were small (<20 mm). Endoscopic repair of GGF was successful intra-operatively in all patients. Two patients had failure of GGF repair at 2 weeks. Other two patients experienced recurrent symptoms after several weeks and had a delayed failure of GGF repair diagnosed by UGI series. Endoscopic repair has remained successful in four patients at 8-46 months follow-up. Endoscopic repair of small GGFs using endoclips is feasible. It must be considered as an option for management of small GGFs, given its safety, and ease of performance compared to revisional surgery.

Feasibility of the transtracheal approach for the thoracic cavity in a large animal model

BACKGROUND

The aim of this study was to evaluate the performance of a novel transtracheal endoscopic technique for thoracic evaluation and intervention in a large animal model.

METHODS

In 12 animals (6 pigs and 6 dogs) under general anesthesia, a tracheal incision was made on the right lateral wall of the lower trachea and used as an entrance for thoracic evaluation and intervention. Postoperative follow-up included endoscopy at 1 and 2 weeks after surgery and necropsy at 2 weeks after surgery.

RESULTS

Transtracheal opening and thoracic exploration were achieved in all animals. Four animals (3 pigs and 1 dog) died as a result of complications from the procedure. At the follow-up endoscopy, healing at the tracheal opening region was noted in seven animals.

CONCLUSIONS

The transtracheal approach to the thoracic cavity is technically feasible in both porcine and canine models (4/12 animals died). The canine model is perhaps more suitable than the porcine model for the study of the transtracheal approach to the thoracic cavity.