Early healing of transcolonic and transgastric natural orifice transluminal endoscopic surgery access sites

Transcolonic Perirectal NOTES Access (PNA): A feasibility study with survival in swine model

Transrectal access still has some unsolved issues such as spatial orientation, infection, access and site closure. This study presents a simple technique to perform transcolonic access with survival in a swine model series. A new technique for NOTES perirectal access to perform retroperitoneoscopy, peritoneoscopy, liver and lymphnode biopsies was performed in 6 pigs, using Totally NOTES technique. The specimens were extracted transanally. The flexible endoscope was inserted through a posterior transmural incision and the retrorectal space. Cultures of bacteria were documented for the retroperitoneal space and intra abdominal cavity after 14 days. Rectal site was closed using non-absorbable sutures. There was no bowel cleansing, nor preoperative fasting. The procedures were performed in 6 pigs through transcolonic natural orifice access using available endoscopic flexible instruments. All animals survived 14 days without complications, and cultures were negative. Histopathologic examination of the rectal closure site showed adequate healing of suture line and no micro abscesses. The results of feasibility and safety of experimental Transcolonic NOTES potentially brings new frontiers and future wider applications for minimally invasive surgery. The treatment of colorectal, abdominal and retroperitoneal diseases through a flexible Perirectal NOTES Access (PNA) is a promising new approach.

A comparison of two endoscopic closures: over-the-scope clip (OTSC) versus KING closure (endoloop + clips) in a randomized long-term experimental study

BACKGROUND

Both over-the-scope clip (OTSC) and KING (endoloop + clips) closures provide reliable and safe full-thickness endoscopic closure. Nevertheless, OTSC clip demonstrated significantly inferior histological healing in the short-term follow-up.

AIM

To compare OTSC versus KING closure of a perforation with regard to long-term effectiveness and macroscopic and histological quality of healing.

METHODS

We performed a randomized experimental study with 16 mini-pigs (mean weight 43.2 ± 11.2 kg). A standardized perforation was performed on the anterior sigmoid wall. KING closure (n = 8) was attained by approximation of an endoloop fixed to the margins of a perforation with endoclips. OTSC closure (n = 8) was performed by deploying OTSC (OVESCO) over the defect. Pigs underwent a control sigmoidoscopy 8 months after the closure to assess the macroscopic quality of healing. Then, autopsy was performed and the rectosigmoid was sent for histopathological assessment.

RESULTS

All closures were completed successfully without air leaks. The duration of closure was similar in both techniques (OTSC 17.8 ± 7.6 min vs. KING 19.6 ± 8.8 min). At autopsy, all KING closures (100 %) were healed with a flat scar without signs of leakage. Microscopically, no inflammatory changes were observed after KING closure. In the OTSC group, microscopic ulcers were present in two pigs (25 %), cryptal abscesses in three pigs (38 %) and significant neutrophil accumulation in all eight pigs (P < 0.01). Giant cell granulomas, dysplasia or abundant scarification was not observed in either group.

CONCLUSIONS

Both OTSC and KING closures offer a long-term reliable seal of a gastrointestinal perforation without stenosis or fistulas. KING closure provides long-term histologically superior healing.

Adverse events of NOTES mediastinoscopy compared to conventional video-assisted mediastinoscopy: a randomized survival study in a porcine model

BACKGROUND

Safety is a concern in natural orifice transluminal endoscopic surgery (NOTES) mediastinoscopy. The objective of this study was to compare the safety of NOTES mediastinoscopy with video-assisted mediastinoscopy (VAM).

METHODS

Twenty-four pigs were randomly assigned to NOTES or VAM. Thirty-minute mediastinoscopies were performed with the identification of seven predetermined structures. The animals were euthanized after 7 days and necropsy was performed.

RESULTS

Mediastinoscopy was not possible in one animal in each group. There were more intraoperative adverse events with NOTES than VAM (7 vs. 2, P = 0.04); hemorrhage was the most frequent adverse event (4 and 1, respectively). At necropsy, pathological findings were observed in 13 animals (9 NOTES and 4 VAM; P = 0.03). Inflammatory parameters were not different between groups and were not related to adverse events.

CONCLUSION

Systematic NOTES mediastinoscopy is possible and comparable to VAM in terms of number of organs identified and inflammatory impact. However, the safety profile of NOTES mediastinoscopy has to be improved before it can be adopted in a clinical setting.

Laparoscopic endoloop technique - A novel approach of managing iatrogenic caecal perforation and literature review

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With our case we have adopted an innovative approach of using endolooping for an early perforation that was within a short distance of the appendicular base, applied proximal to the site of the perforation.

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In our surgery, the area of ischemic injury can be easily visualized through the laparoscopy and including fresh and healthy tissue margins in the loop is the hallmark of safety for this simple technique.

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The endoloop technique described, undertaken during a laparoscopy is a novel approach. It is a simple and effective method, reminding clinicians to adapt techniques when necessary.

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Nevertheless, it is only limited to perforations around the appendicular base. The endolooping technique may not be suitable for late presentation, large perforations with ischemic or friable tissue, and severe peritonitis. In such cases, the use of other methods, such as wedge resection or stapling would be safer.

Introduction

An iatrogenic caecal perforation is rare, but a serious complication associated with significant morbidity and mortality. We present a 4 min and 50 s video on a new improvisation undertaken during laparoscopic management of post-polypectomy caecal perforation.

Presentation of case

Our patient presented with an acute abdomen following endoscopic polypectomy. At surgery, the site of caecal perforation was close to the appendicular base with devitalization tissue, secondary to diathermy usage. The hallmark of safety within this novel technique included fresh healthy tissue margins within the endoloop (detachable snare ligation) and ensuring no ischemic tissue was gathered. Complete freeing of the appendix and meso-appendicular base was required and securing three endoloops proximal to the site of perforation. The post-operative course was uneventful.

Discussion

The World Society of Emergency Surgery (WSES) 2013 guidelines suggested an early laparoscopic approach is a safe and effective treatment for colonoscopy-related colonic perforation. There are no national guidelines and the management is dictated by the clinical condition of the patient, co-morbidity, size and site of perforation as well as the scale of bowel preparation, and surgical experience.

Conclusion

The endoloop technique described, undertaken during a laparoscopy is a novel approach. It is a simple and effective method, reminding clinicians to adapt techniques when necessary. Nevertheless, it is only limited to perforations around the appendicular base.

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.

Comparison of transrectal and transvaginal hybrid natural orifice transluminal endoscopic surgery partial nephrectomy in the porcine model

OBJECTIVE

To compare the feasibility of porcine transrectal (TR) and transvaginal (TV) hybrid natural orifice transluminal endoscopic surgery (NOTES) partial nephrectomy (PN), as NOTES nephrectomy has recently been performed in the porcine model.

MATERIALS AND METHODS

A total of 10 female pigs (weight 45 kg) underwent TR (n = 5) or TV (n = 5) NOTES PN. The pneumoperitoneum was created by a periumbilical 12-mm trocar, through which a laparoscope was advanced for intra-abdominal visualization. For TV-NOTES PN, a gastroscope was used to obtain TV peritoneal access. For TR-NOTES PN, a horizontal incision was made 2 cm above the dentate line, and a submucosal tunnel was created in the posterior rectal wall. The gastroscope was advanced through the submucosal tunnel and retroperitoneum to the kidney, and a peritoneal window was created. For both TR- and TV-NOTES PN, the gastroscope was exchanged for the SPIDER Surgical System. Flexible dissecting instruments and hook cautery introduced through the SPIDER Surgical System were used to mobilize the kidney. A harmonic scalpel introduced periumbilically was used to excise a portion of the lower pole. LAPRA-TY-secured sutured renorrhaphy was performed, followed by TR or TV specimen extraction.

RESULTS

TR- and TV-NOTES PN was successfully performed in all 10 pigs. A comparison of TR- and TV-NOTES PN revealed no significant differences in the mean access time (29.2 vs 29.6 minutes, P = .944), operative time (196.0 vs 183.0 minutes, P = .631), and estimated blood loss (59.0 vs 54.0 mL, P = .861). Necropsy did not demonstrate abdominal injuries.

CONCLUSION

We have demonstrated proof-of-principle for TR and TV-NOTES PN in swine, with comparable perioperative parameters. Preclinical survival studies are requisite to assess the potential of TR-NOTES as an alternative to TV-NOTES.

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.

Feasibility of Endoscopic Transoral Surgical Lung Biopsy in a Live Canine Model

Background. The feasibility of using a transoral approach to the thoracic cavity has not yet been measured in humans or animals. The present study aimed to evaluate the feasibility of transoral surgical lung biopsy (TOLB) in 10 canines. Methods. Through an incision over the vestibulum oris, a homemade metal tube was introduced into the thoracic cavity under endoscopic guidance and used as a working channel of surgical lung biopsy. TOLB was performed on the predetermined lung lobe by using an electrocautery loop and endoscopic grasper. Results. Successful surgical lung biopsy was achieved in 8 of 10 animals in a mean time of 132 minutes (range 130-190 minutes). There were no major intraoperative or postoperative complications, and all animals survived for 2 weeks after surgery. Autopsy showed no evidence of vital structure injury, mediastinitis, or empyema. Conclusions. TOLB was demonstrated to be safe and feasible in a canine model.

Original technique to close the transrectal viscerotomy access in a NOTES transrectal and transgastric segmental colectomy

Segmental colectomy is an ideal procedure for natural orifice transluminal endoscopic surgery (NOTES). Transanal endoscopic approaches have enabled rectosigmoid colectomy through a viscerotomy that is resected with the specimen. To extend NOTES segmental colectomy to the entire colon and beyond, a rectal viscerotomy will have to be safely and effectively closed at the end of the procedure. A new technique for rectal viscerotomy closure using a circular EEA hemorrhoid and prolapse stapler with DST series technology (Covidien) is described.

Development of a feasible transrectal natural orifice transluminal endoscopic surgery (NOTES®) approach in a cadaveric appendectomy model: anterior is better

BACKGROUND

The transrectal natural orifice transluminal endoscopic surgery (NOTES) approach is a potentially promising alternative to transgastric or transvaginal approaches for intraperitoneal procedures. However, whether the optimal transrectal approach for intraperitoneal surgery is anterior or posterior remains unknown. To evaluate this, a prospective comparison of anterior and posterior transrectal NOTES approaches in a cadaveric appendectomy model was performed.

METHODS

Operations were performed on human cadavers using a transanal endoscopic microsurgery (TEM) scope to assist with access and closure. Posterior access was achieved by tunneling cephalad through the retrorectal space into the peritoneal cavity. Anterior transrectal access was established through the rectal wall just above the peritoneal reflection. A dual-channel flexible endoscope was used to perform appendectomies. Rectotomies were closed using sutures or staples. Operative time, degree of laparoscopic assistance, complications, and leak-testing results were recorded.

RESULTS

This study investigated 10 cadavers with access and closure attempted using both anterior (n = 10) and posterior (n = 5) approaches, whereas appendectomies were performed using either an anterior (n = 8) or a posterior (n = 2) approach. The anterior approach required less time than the posterior approach for peritoneal access (4 ± 1 vs. 61 ± 14 min; p < 0.001), specimen extraction (2 ± 1 vs. 5 ± 1 min; p < 0.01), and the total operation (99 ± 35 vs. 176 ± 26 min; p = 0.02). A "pure" NOTES dissection was possible with the anterior approach using rigid transanal instruments for assistance. Dissection time, closure time, and the incidence of complications were similar between the two approaches. Leak testing of closures showed significant variability for all closure types.

CONCLUSION

Transrectal NOTES appendectomy is feasible in a cadaveric model using an anterior transrectal approach. This approach is technically easier, results in shorter operative times, and allows for a "pure" NOTES dissection compared with a posterior transrectal approach. Leak pressure testing of NOTES closures is unreliable in the cadaveric model.

Transrectal hybrid natural orifice transluminal endoscopic surgery (NOTES) nephrectomy in a porcine model

OBJECTIVE

To examine feasibility of transrectal hybrid natural orifice translumenal endoscopic surgery (NOTES) nephrectomy in the porcine model. NOTES uses ports of entry to the peritoneal cavity instead of abdominal wall incisions, thereby eliminating visible scar and also potentially reducing postoperative pain.

METHODS

After obtaining Institutional Animal Care and Use Committee approval, 3 female pigs (45 kg) underwent transrectal hybrid NOTES nephrectomy (2 right, 1 left). Pneumoperitoneum was created by a periumbilically-inserted 12-mm trocar, through which a laparoscope was advanced to obtain intraabdominal visualization. A horizontal incision was made 2 cm above the dentate line and a submucosal tunnel was created in the posterior rectal wall/presacral space. A dual-channel gastroscope was advanced through the submucosal tunnel and retroperitoneum to the level of the kidney using air insufflation. A window in the peritoneum was created and renal mobilization was completed. A transumbilically applied laparoscopic 45-mm stapler was used to transect the ureter and renal hilum. A specimen extraction bag was deployed transrectally and the specimen was delivered intact, followed by transrectal incision closure.

RESULTS

Transrectal hybrid NOTES nephrectomy was successfully performed in all cases. Mean operative time was 180 minutes (30 minutes for rectal access). Estimated blood loss was 50 mL. On necropsy, no intraabdominal injuries were noted.

CONCLUSIONS

In this initial report on feasibility of transrectal hybrid NOTES nephrectomy, we were able to perform the procedures with minimal blood loss and extract intact specimen. Survival studies are prerequisite to assess sterility and short- and long-term complications. This approach may be useful as an alternative to transvaginal access.

Natural orifice translumenal endoscopic surgery (NOTES(®)): a technical review

INTRODUCTION

The clinical NOTES literature continues to grow. This review quantifies the published human NOTES experience to date, examines instrument use in detail, and compiles available perioperative outcomes data.

METHODS

A PubMed search for all articles describing human NOTES cases was performed. All articles providing a technical description of procedures, excluding cases limited to diagnostic procedures, specimen extraction, fluid drainage or gynecological procedures, were reviewed. Two reviewers systematically cataloged the technical details of each procedure and performed a frequency analysis of instrument use in each type of case. Available outcomes data were also compiled.

RESULTS

Forty-three discrete articles were reviewed in detail, describing a total of 432 operations consisting of transvaginal (n = 355), transgastric (n = 58), transesophageal (n = 17), and transrectal (n = 2) procedures, with 90% of cases performed in hybrid fashion with laparoscopic assistance. Cholecystectomy (84% of cases) was the most common procedure. Analysis of key steps included choice of endoscope, establishment of peritoneal access, dissection, specimen extraction, and closure of the access site. Analysis of instrument use during transvaginal cholecystectomy revealed variation in the choice of endoscope and the technique for establishment of access. A majority of these procedures relied heavily on the use of rigid and transabdominal instrumentation. Closure of the vaginotomy site was found to be well standardized, performed with an open suturing technique. Similar analysis for transgastric procedures revealed consistency in the choice of flexible endoscope as well as access and closure techniques. Perioperative outcomes from NOTES procedures were reported, but the data are currently limited due to small case numbers.

CONCLUSIONS

NOTES is most commonly performed using a hybrid, transvaginal approach. Although some aspects of these procedures appear to be well standardized, there is still significant variability in technique. More outcomes data with standardized reporting are needed to determine the actual risks and benefits of NOTES.

Natural orifice translumenal endoscopic surgery (NOTES(®)): a technical review

INTRODUCTION

The clinical NOTES literature continues to grow. This review quantifies the published human NOTES experience to date, examines instrument use in detail, and compiles available perioperative outcomes data.

METHODS

A PubMed search for all articles describing human NOTES cases was performed. All articles providing a technical description of procedures, excluding cases limited to diagnostic procedures, specimen extraction, fluid drainage or gynecological procedures, were reviewed. Two reviewers systematically cataloged the technical details of each procedure and performed a frequency analysis of instrument use in each type of case. Available outcomes data were also compiled.

RESULTS

Forty-three discrete articles were reviewed in detail, describing a total of 432 operations consisting of transvaginal (n = 355), transgastric (n = 58), transesophageal (n = 17), and transrectal (n = 2) procedures, with 90% of cases performed in hybrid fashion with laparoscopic assistance. Cholecystectomy (84% of cases) was the most common procedure. Analysis of key steps included choice of endoscope, establishment of peritoneal access, dissection, specimen extraction, and closure of the access site. Analysis of instrument use during transvaginal cholecystectomy revealed variation in the choice of endoscope and the technique for establishment of access. A majority of these procedures relied heavily on the use of rigid and transabdominal instrumentation. Closure of the vaginotomy site was found to be well standardized, performed with an open suturing technique. Similar analysis for transgastric procedures revealed consistency in the choice of flexible endoscope as well as access and closure techniques. Perioperative outcomes from NOTES procedures were reported, but the data are currently limited due to small case numbers.

CONCLUSIONS

NOTES is most commonly performed using a hybrid, transvaginal approach. Although some aspects of these procedures appear to be well standardized, there is still significant variability in technique. More outcomes data with standardized reporting are needed to determine the actual risks and benefits of NOTES.

Yes, we can: reliable colonic closure with the Padlock-G clip in a survival porcine study (with video)

BACKGROUND

Secure closure of the colonic access site is one of the most important issues for the development of natural orifice transluminal endoscopic surgery.

OBJECTIVE

To evaluate the feasibility, reproducibility, and efficacy of a new over-the-scope clip.

DESIGN

Descriptive study, in vivo porcine colon.

INTERVENTION

In 10 female Yorkshire pigs weighing 30 to 35 kg, a 10-mm colotomy was performed by using a needle-knife and advancing the endoscope to the peritoneal cavity. Colonic closure was performed by using the Padlock-G clip (Aponos Medical, Kingston, NH) delivered with the Lock-It system (Aponos).

MAIN OUTCOME MEASUREMENTS

Animals were monitored daily for signs of peritonitis and sepsis over a period of 14 days. During necropsy, the peritoneal cavity was examined, and the colon segment containing the incision was excised for pathological study.

RESULTS

Closure was achieved in all cases. Nine of 10 pigs survived 14 days without complications, but 1 pig was killed immediately after the procedure because of severe bleeding during the colonic incision. The median closure time was 8 minutes (range 1-30 minutes). At necropsy, adhesions were observed in 5 cases. The incision was hardly visible at the serosa side in 3 cases and was not identified in 6 cases. In 6 cases, the clip was still slightly attached to the mucosa, and it was not found in 3 cases. The pathological study revealed a complete remodeling of the colonic wall in all cases.

LIMITATIONS

Animal model, noncomparative study.

CONCLUSION

The Padlock-G clip procedure is feasible, reproducible, effective, and easy to perform, and it provides a reliable colonic closure.