Endoscopic colotomy closure for natural orifice transluminal endoscopic surgery using a T-fastener prototype in comparison to conventional laparoscopic suture closure

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.

"Down-to-Up" transanal NOTES Total mesorectal excision for rectal cancer: Preliminary series of 9 patients

BACKGROUND:

Applications for natural orifice translumenal endoscopic surgery (NOTES) to access the abdominal cavity have increased in recent years. Despite potential advantages of transanal and transcolonic NOTES for colorectal pathology, it has not been widely applied in the clinical setting. This study describes a series of nine patients for whom we performed transanal retrograde (“Down-to-Up”) total mesorectal excision for rectal cancer.

MATERIALS AND METHODS:

Under IRB approval, informed consent was obtained from each patient with rectal adenocarcinoma. Rectosigmoidectomy with total mesorectal excision was performed using low rectal translumenal access to the mesorectal fascia and subsequent dissection in a retrograde fashion. This was achieved using either a single port device or flexible colonoscope with endoscopic instrumentation and laparoscopic assistance. This was followed by transanal extraction of the specimen and hand-sewn anastomosis.

RESULTS:

Mean operative time was 311 min. Mean hospital stay was 7.56 days. Complications occurred in two patients, and consisted of one anastomotic leakage with reoperation and one intraoperative conversion to open surgery because of impossibility to dissect the specimen. TME specimen integrity was adequate in six patients.

CONCLUSION:

This series suggests that a retrograde mesorectal dissection via a NOTES technique is feasible in patients with rectal adenocarcinoma. This technique may act as a complimentary part of operative treatment for rectal cancer alongside other minimally invasive strategies. Long-term follow up will be needed to assess oncological results.

"Down-to-Up" transanal NOTES Total mesorectal excision for rectal cancer: Preliminary series of 9 patients

BACKGROUND

Applications for natural orifice translumenal endoscopic surgery (NOTES) to access the abdominal cavity have increased in recent years. Despite potential advantages of transanal and transcolonic NOTES for colorectal pathology, it has not been widely applied in the clinical setting. This study describes a series of nine patients for whom we performed transanal retrograde ("Down-to-Up") total mesorectal excision for rectal cancer.

MATERIALS AND METHODS

Under IRB approval, informed consent was obtained from each patient with rectal adenocarcinoma. Rectosigmoidectomy with total mesorectal excision was performed using low rectal translumenal access to the mesorectal fascia and subsequent dissection in a retrograde fashion. This was achieved using either a single port device or flexible colonoscope with endoscopic instrumentation and laparoscopic assistance. This was followed by transanal extraction of the specimen and hand-sewn anastomosis.

RESULTS

Mean operative time was 311 min. Mean hospital stay was 7.56 days. Complications occurred in two patients, and consisted of one anastomotic leakage with reoperation and one intraoperative conversion to open surgery because of impossibility to dissect the specimen. TME specimen integrity was adequate in six patients.

CONCLUSION

This series suggests that a retrograde mesorectal dissection via a NOTES technique is feasible in patients with rectal adenocarcinoma. This technique may act as a complimentary part of operative treatment for rectal cancer alongside other minimally invasive strategies. Long-term follow up will be needed to assess oncological results.

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.

Perirectal NOTES access: "down-to-up" total mesorectal excision for rectal cancer

OBJECTIVES

Clinical natural orifice surgery has been applied for abdominal surgery in recent years, mostly by vaginal and oral access. The study describes preliminary successful human applications of transcolonic natural orifice transluminal endoscopic surgery (NOTES), using a new transrectal total mesorectal excision procedure for rectal cancer.

METHODS

Institutional review board approval was obtained for the study. In 2 patients with rectal adenocarcinoma, total mesorectal resection and rectosigmoidectomy with lymphadenectomy was performed using a low NOTES transcolonic access. "Down-to-up" mesorectal dissection was achieved either using a flexible scope or a transrectal single port device. The specimens were extracted transanally, and transorificial low anastomosis was performed.

RESULTS

Operative time was 350 and 360 minutes, respectively; no complications occurred and patients were discharged after 6 days.

CONCLUSION

Successful human reports on transcolonic NOTES suggest potential applications. The treatment of colorectal diseases through transorificial single port or flexible perirectal NOTES access are promising new approaches besides current methods to improve patient care.

A novel flexible endoluminal stapling device for use in NOTES colotomy closure: a feasibility study using an ex vivo porcine model

BACKGROUND

With advances in endoscopic diagnosis of early-stage gastrointestinal pathology, the need to offer minimally invasive treatment is attracting significant interest. It is essential that secure and consistent closure of full-thickness colonic resections and colotomy access be provided in natural orifice translumenal surgery (NOTES). This ex vivo porcine study aimed to evaluate a novel prototype flexible endoscopic stapler device for use in closure of full-thickness colonic defects.

METHODS

A feasibility study using ex vivo porcine colon was undertaken to explore the potential of the prototype stapler to close and seal a colotomy. A standardized linear colotomy was created in 30 colons. The novel flexible endostapler was used to close 20, interrupted hand-sewn sutures to close 5, and a well-validated linear stapler to close 5 of these colotomies. The colons were subsequently subjected to leak pressure testing.

RESULTS

The colotomy closure using the prototype stapler endoluminally required a median time of 280 s. No statistically significant difference in leak pressures between the stapler and the other techniques was described. Although the endostapler without any colotomy was found to have the highest median leak pressures and the interrupted sutures the lowest pressures, no significant difference could be demonstrated (p = 0.52). Furthermore, no significant difference was demonstrated when the closure integrity created by the flexible stapler was compared with that created by the well-validated linear stapler.

CONCLUSION

The results suggest that the flexible endoscopic stapler is an effective device for the safe closure of a visceral defect, which in this feasibility study was equivalent to other well-established techniques. Further studies will focus on in vivo application of the prototype stapling device in the setting of full-thickness colonic resection.

Transgastric cholecystectomy: From the laboratory to clinical implementation

After the first report by Kalloo et al on transgastric peritoneoscopy in pigs, it rapidly became apparent that there was no room for an under-evaluated concept and blind adoption of an appealing (r)evolution in minimal access surgery. Systematic experimental work became mandatory before any translation to the clinical setting. Choice and management of the access site, techniques of dissection, exposure, retraction and tissue approximation-sealing were the basics that needed to be evaluated before considering any surgical procedure or study of the relevance of natural orifice transluminal endoscopic surgery (NOTES). After several years of testing in experimental labs, the revolutionary concept of NOTES, is now progressively being experimented on in clinical settings. In this paper the authors analyse the challenges, limitations and solutions to assess how to move from the lab to clinical implementation of transgastric endoscopic cholecystectomy.

Endoscopic closure of gastrogastric fistulas by using a tissue apposition system (with videos)

BACKGROUND

Gastrogastric fistulas (GGFs) are seen in 1.5% to 12.5% of patients after Roux-en-Y gastric bypass (RYGB) bariatric surgery, often leading to failure to lose adequate weight.

OBJECTIVE

The aim of this study was to assess the feasibility, safety, and percentage of successful primary endoluminal closures of GGFs by using a recently developed tissue apposition system in combination with local mucosectomy.

DESIGN

A feasibility and outcome study following institutional review board protocol.

SETTING

Tertiary referral teaching hospital, Legacy Health System, Portland, Oregon.

INTERVENTIONS

A combination of mucosectomy and nonresorbable tissue apposition is used to achieve a permanent closure of the GGF.

PATIENTS

Four patients with 5 GGFs after RYGB; the mean fistula diameter of was 18.6 mm (range 10-30 mm).

RESULTS

Primary closure rate (1 endoscopic session) of 5 GGFs was 100%. The mean procedure time was 88.5 minutes. One to 4 pairs of tissue anchors were used to close the fistulas. The mean time for performing mucosectomy was 21.6 minutes (range 8-42 minutes) and 39.6 minutes (range 12-58 minutes) for fistula closure. Estimated blood loss was on average 2 mL (range 0-5 mL). No complications were recorded. Early success (3 months), as evidenced by early satiety and weight loss, was noted for 3 of 4 patients. After 3 months, only the smallest fistula (10 mm) was still completely closed, and after 6 months, it also showed a pinhole opening.

CONCLUSION

It was feasible to close all fistulas endoscopically without complications. Permanent closure of GGFs could not be achieved.

Cirurgia por orifícios naturais transcolônica: acesso NOTES peri-retal (PNA) para excisão mesoretal total

OBJETIVOS: Cirurgia por orifícios naturais tem sido recentemente aplicada em series clínicas para cirurgia abdominal. Apesar de potenciais vantagens do acesso NOTES transcolônico para doenças colorretais, este ainda não havia sido utilizado clinicamente. O presente trabalho descreve a primeira aplicação bem-sucedida de NOTES transcolônico da literatura, em uma nova abordagem de excisão mesoretal total (TME) para cancer de reto. MÉTODOS: Foi obtida aprovação de Comitê de Ética em Pesquisa para cirurgias por orifícios naturais, e o paciente assinou termo de consentimento informado. Em um paciente de 54 anos portador de adenocarcinoma de reto, o procedimento de retossigmoidectomia e linfadenectomia, com excisão mesoretal total foi realizada utilizando um acesso posterior transcolônico pouco acima da borda anal. A dissecção mesorretal foi conseguida utilizando um colonoscópio flexível e instrumentos endoscópicos, com assistência laparoscópica. O espécime foi retirado via transanal, e anastomose foi transorificial, com estoma proximal de proteção. RESULTADOS: O tempo operatório foi de 350 min, não ocorrendo complicações operatórias. A evolução pós-operatória foi favorável, e o paciente recebeu alta no sexto dia de pós-operatório com dieta plena. CONCLUSÃO: Este primeiro relato bem sucedido de cirurgia NOTES transcolônica traz potencialmente novas fronteiras de aplicações clínicas na cirurgia minimamente invasiva. O tratamento de doenças colorretais utilizando o novo acesso flexível PNA (Perirectal NOTES Access) é uma promissora nova abordagem, paralelamente à laparoscopia e cirurgia aberta, para melhoria do tratamento dos pacientes.

Natural orifice surgery applied for colorectal diseases

Clinical natural orifice surgery has been applied to abdominal surgery in recent years, mostly using transvaginal and transgastric access. Rectal and transcolonic natural orifice transluminal endoscopic surgery (NOTES) were tested in animal and cadaver models by a few research groups. Despite the potential advantages of transcolonic NOTES for colorectal diseases, it has not yet been clinically applied. The first successful series of human applications of transcolonic NOTES in the literature from the NOTES Research Group in Brazil provide new possibilities in the field in new transrectal procedures for rectal cancer and benign disease. Successful first human reports on Transcolonic NOTES potentially brings new frontiers and applications for minimally invasive surgery. The treatment of colorectal diseases through flexible Perirectal NOTES Access is a promising new approach alongside existing laparoscopic and open surgery to improve patient care.

Survival study of natural orifice translumenal endoscopic surgery for rectosigmoid resection using transanal endoscopic microsurgery with or without transgastric endoscopic assistance in a swine model

BACKGROUND

The feasibility of transanal rectosigmoid resection with transanal endoscopic microsurgery (TEM) was previously demonstrated in a swine nonsurvival model in which transgastric endoscopic assistance also was shown to extend the length of colon mobilized transanally.

METHODS

A 2-week survival study evaluating transanal endoscopic rectosigmoid resection with stapled colorectal anastomosis was conducted with swine using the transanal approach alone (TEM group, n = 10) or a transanal approach combined with transgastric endoscopic assistance (TEM + TG group, n = 10). Gastrotomies were created using a needleknife and balloon dilation, then closed using prototype T-tags. Outcomes were evaluated and compared between the groups using Student's t-test and Fisher's exact test.

RESULTS

Relative to the TEM group, the average length of rectosigmoid mobilized in the TEM + TG group was 15.6 versus 10.5 cm (p < 0.0005), the length of the resected specimen was 9 versus 6.2 cm (p < 0.0005), and the mean operative time was 254.5 versus 97.5 min (p < 0.0005). Intraoperatively, no organ injury or major bleeding was noted. Two T-tag misfires occurred during gastrotomy closure and four small staple line defects requiring transanal repair including one in the TEM group and three in the TEM + TG group (p = 0.2). Postoperatively, there was no mortality, and the animals gained an average of 3.4 lb. Two major complications (10%) were identified at necropsy in the TEM + TG group including an intraabdominal abscess and an abdominal wall hematoma related to T-tag misfire. Gastrotomy closure sites and colorectal anastomoses were all grossly healed, with adhesions noted in 60 and 70% and microabscesses in 50 and 20% of the gastrotomy sites and colorectal anastomoses, respectively.

CONCLUSIONS

Natural orifice translumenal endoscopic surgery (NOTES) for rectosigmoid resection using TEM with or without transgastric endoscopic assistance is feasible and associated with low morbidity in a porcine survival model. Transgastric assistance significantly prolongs the operative time but extends the length of the rectosigmoid mobilized transanally, with a nonsignificant increase in complication rates related to gastrotomy creation.

Endoluminal compression clip: full-thickness resection of the mesenteric bowel wall in a porcine model

BACKGROUND

Performing a full-thickness intestinal wall resection of a sessile polyp located on the mesenteric side with a compression clip may lead to compression of mesenteric vessels. The application of such a clip may therefore cause a compromised blood supply in the particular bowel segment, leading to perforation.

OBJECTIVE

To evaluate the performance of a newly developed, nitinol compression clip, called the NiTi clamp, for full-thickness resection of the bowel wall, while the clip is deliberately deployed endoluminally on the mesenteric side.

DESIGN

Prospective animal study. Multinational, multidisciplinary; gastroenterology and general surgery, research cooperation.

SETTING

Animal research laboratory.

INTERVENTION

Six pigs were operated upon and endoscopically evaluated and then killed after 3 weeks. Linear compression closure clips based on nitinol springs were used. Three longitudinal enterotomies were performed: in the cecum, spiral colon, and proximal rectum. Four clips were deployed in each animal.

MAIN OUTCOME MEASUREMENTS

A total of 23 clips were deployed. The average expulsion day was 9 days.

RESULTS

All but 3 clips were normally expelled. One pig developed bowel ischemia due to intussusception. In endoscopic procedures, no signs of significant segmental mucosal ischemia were found. The macroscopic appearance of the compression closure lines was thin and delicate, but epithelialization was significantly delayed at 5 sites.

LIMITATION

Differences between porcine and human colorectal anatomy.

CONCLUSION

Full-thickness clamping of the bowel with the NiTi clamp, including the local mesenteric vasculature, does not significantly impair local healing of the clamp site and gives hope to further development of novel full-thickness endoscopic resection technologies.

[The future of gastrointestinal therapeutic endoscopy: NOTES]

Natural orifice translumenal endoscopic surgery (NOTES) allows access into the peritoneal cavity with a flexible endoscope, through the wall of the digestive or urogenital tracts. NOTES can be combined to laparoscopic surgery in so-called << hybrid >> techniques. In the absence of any incision of the abdominal wall, NOTES procedures provide perfect cosmetic results, with virtually no risk of parietal complications, and with decreased postoperative pain. NOTES could particularly benefit to overweight patients and to patients receiving intensive or palliative care. Most NOTES studies have been performed on animal models, with great interest for both transgastric and transpelvic approaches. Successful NOTES peritoneoscopy, hysterectomy, oophorectomy, tubal ligation, gastrojejunal anastomosis, cholecystectomy, splenectomy, nephrectomy, and abdominal-wall hernia repair have been described. In human studies, the transvaginal route is preferred. NOTES clinical research focuses on low-morbidity procedures, such as cholecystectomy, appendectomy, and peritoneoscopy. Indirect benefits are expected from this research, with possible technological innovations in the field of endoscopic instrumentation (including sutures, anastomosis, traction and triangulation). Overall, NOTES is believed to make evolve both interventional endoscopy and minimally invasive surgery.

Colonic sterilization for natural orifice translumenal endoscopic surgery (NOTES) procedures: a comparison of two decontamination protocols

BACKGROUND

This study aimed to evaluate the effect of two different sterilization protocols on the bacterial counts in the swine colon as preparation for natural orifice translumenal endoscopic surgery (NOTES) surgery.

METHODS

In this study, 16 swine were randomized to two different colonic sterilization protocols: low colonic irrigation using 300 ml of a 1:1 dilution of 10% povidone-iodine (Betadine) with sterile saline, followed by 1 g of cefoxitin dissolved in 300 ml of saline or two consecutive 300-ml irrigations using a quaternary ammonium antimicrobial agent (Onamer M). Colonic cultures were taken before colonic cleansing after a decontamination protocol and after completion of the NOTES procedure. The Invitrogen live/dead bacterial viability kit was used to assess for change in the bacterial load. A qualitative culture of peritoneal fluid was obtained at the end of the NOTES procedure. Colon mucosal biopsies obtained immediately after the sterilization procedure and at the 2-week necropsy point were evaluated for mucosal changes.

RESULTS

Protocol 1 resulted in an average 93% decrease in live colonic bacteria versus 90% with protocol 2 (nonsignificant difference). After a NOTES procedure, group 1 had a 62% increase in live bacteria and group 2 had a 31% increase (nonsignificant difference). Peritoneal cultures also were obtained. Bacteria were isolated from the peritoneal fluid of all the animals, and two or more species were isolated from 75% of the animals. There was no evidence of peritoneal infection at necropsy. Reactive epithelial changes and mild inflammation were the only pathologic abnormalities. No changes were noted at histologic evaluation of colonic mucosa after 2 weeks, demonstrating that these were temporary changes.

CONCLUSION

Colonic irrigation with Betadine and antibiotics are as effective for bacterial decontamination of the swine colon as a quaternary ammonium compound. The results of this study support the use of either protocol. Despite thorough decontamination, peritoneal contamination occurs. The significance of this for humans is unknown.

Gastrotomy creation and closure for NOTES using a gastropexy technique (with video)

BACKGROUND

Safe and efficient gastrotomy creation and closure is pivotal for natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

To test a method of transgastric access and closure with commercially available devices.

DESIGN

An animal survival study.

SETTING

University hospital.

PATIENTS

Fifteen pigs.

INTERVENTIONS

By using a surgical suture passer, under endoscopic guidance, 3 percutaneous stay sutures were placed, in a triangular fashion, through the gastric wall. A gastrotomy was created with a dilation balloon, which was introduced over a guidewire through the gastric wall in the center of the 3 sutures. After performing a NOTES procedure, the gastrotomy was closed by tying the sutures. Necropsies were performed after 2 to 4 weeks.

MAIN OUTCOME MEASUREMENTS

Success and time of gastrotomy creation and closure, and intraoperative and postoperative complications.

RESULTS

Gastrotomies were successfully created and closed in all the animals. The median time to create a gastrotomy was 19 minutes (range 11-85 minutes), and the median closure time was 1 minute (range 1-45 minutes). One pig died on postoperative day 1 because of peritonitis caused by a leaking gastrotomy site that extended beyond the stay sutures. There were no other gastrotomy-related complications. All gastrotomies were well healed at the necropsy.

LIMITATION

No control group.

CONCLUSIONS

We evaluated a simple method by using the principles of the PEG technique combined with a gastropexy, which is familiar to the majority of endoscopists. Strict attention to the gastrotomy site is needed, because one leak was from the gastrotomy site that extended beyond the stay sutures.

Stent placement for benign colonic stenosis: case report, review of the literature, and animal pilot data

BACKGROUND

Permanent metal stent placement for malignant intestinal obstruction has been proven to be efficient. Temporary stents for benign conditions of the colon and rectum are less studied. This is a case study, review of the literature, and observation from an animal model on placement of stents in the colorectum for benign disease.

MATERIALS AND METHODS

A 55-year-old man presented with recurrent obstructions from a benign stricture of the distal sigmoid colon. After failed balloon dilations, a polyester coated stent was placed. The purpose of the stent was to improve symptoms and avoid surgery. The stent was expelled after 5 days. We conducted a literature review of stents placed for benign colorectal strictures and an animal study to evaluate stent migration.

RESULTS

In the literature, there were 53 reports of uncovered metal stents, four covered metal stents, and six polyester stents. Patency rates were 71%, and migration rate was 43%. Migration occurred earlier with polyester stents (mean=8 days) versus covered (32 days) or uncovered metal stents (112 days). Severe complications were seen in 23% of patients. Four 45-kg pigs underwent rectosigmoid transection with a 21-mm anastomosis and endoscopic placement of a Polyflex stent. Two stents were secured with suture. Stents without fixation were expelled within 24 h of surgery. Stents with fixation were expelled between postoperative days 2 and 14.

CONCLUSION

Stents for the treatment of benign colorectal strictures are safe, with comparable patency rates between stent types. Metal stents can cause severe complications. In a pig model, covered polyester stents tend to migrate early even with fixation. Further investigation needs to focus on new stent designs and/or better fixation.