Transvaginal cholecystectomy without laparoscopic support using prototype flexible endoscopic instruments in a porcine model.

BACKGROUND: Transvaginal cholecystectomy with laparoscopic assistance has been performed safely in humans. The next goal was to develop a natural orifice transluminal endoscopic surgery (NOTES) technique to perform cholecystectomy without laparoscopic instruments using one flexible endoscope and flexible accessories. The aim of the study was to test the feasibility of the procedure in a survival porcine model. METHODS: Cholecystectomies were attempted in five 88-130-lb. pigs with a planned 2-week survival. Prototype flexible instruments (NOTES Toolbox, Ethicon Endo-Surgery, Inc.) were used to aid in access, dissection, and removal of the gallbladder via the transvaginal route. RESULTS: Cholecystectomy could be completed without abdominal incision using prototype instruments in four out of five pigs. The cystic duct could be exposed with a flexible hook knife and clips applied. The steerable trocar improved stability and the precision of the dissection. The critical view was established in all five pigs. Dissection of the gallbladder off the liver bed was imprecise resulting in gallbladder perforation in all pigs and liver hemorrhage in two. At necropsy, all clips on the cystic duct were secure and no bile leak, bowel injury, or adhesions were present. CONCLUSIONS: NOTES cholecystectomy without laparoscopic support is feasible but challenging using prototype flexible endoscopic devices. A prototype clip applier was effective in controlling the cystic duct. Further improvements in instrument design to ensure precision and safety are needed before flexible devices should be used for pure NOTES procedures in humans.

In search of the best peritoneal adhesion model: comparison of different techniques in a rat model.

BACKGROUND: Adhesion-related complications after abdominal surgery result in significant morbidity and costs. Results from animal studies investigating prevention or treatment of adhesions are limited due to lack of consistency in existing animal models. The aim of this study was to compare quality and quantity of adhesions in four different models and to find the best model. MATERIALS AND METHODS: This study was approved by the University of Missouri Animal Care and Use Committee (ACUC). Forty female rats were randomly assigned to four different groups of 10 animals each. Adhesion created was performed utilizing the four techniques: Group 1 - parietal peritoneum excision (PPE), Group 2 - parietal peritoneum abrasion (PPA), Group 3 - peritoneal button creation (PBC), and Group 4 - cecal abrasion (CA). Rats were allowed to recover and necropsy was performed on postoperative d 14. Adhesions were scored by an established quantitative and qualitative scoring systems. The midline incision served as the control in each animal. RESULTS: The four groups were not equal with respect to both quantity score (P<0.001) and quality score (P=0.042). The PBC group had the highest quantity of adhesions. The highest quality of adhesion was seen in the PPE group. A multivariate analysis carried out to quantify the performance of each model clearly demonstrated that PBC exhibited the best results in terms of both quantity and quality. CONCLUSIONS: The button technique (PBC) is most consistent and reproducible technique for an intra-abdominal adhesion model. This model can help in the study and development of substances to prevent adhesion formation in the future.

Transvaginal repair of a large chronic porcine ventral hernia with synthetic mesh using NOTES.

BACKGROUND: Ventral incisional hernias still remain a common surgical problem. We tested the feasibility of transvaginal placement of a large synthetic mesh to repair a porcine hernia. METHODS: Seven pigs were used in this survival model. Each animal had creation of a 5-cm hernia defect and underwent a transvaginal repair of the defect with synthetic mesh. A single colpotomy was made using a 12-cm trocar for an overtube. The mesh was cut to size and placed through the trocar. A single-channel gastroscope with an endoscopic atraumatic grasper was used for grasping sutures. Further fascial sutures were placed every 5 cm. RESULTS: Mesh repair was feasible in all 7 animals. Mean operative time was 133 minutes. Technical difficulties were encountered. No gross contamination was seen at the time of necropsy. However, 5 animals had positive mesh cultures; 7 had positive cultures in the rectouterine space in enrichment broth or on direct culture. CONCLUSION: Transvaginal placement of synthetic mesh to repair a large porcine hernia using NOTES is challenging but feasible. Future studies need to be conducted to develop better techniques and determine the significance of mesh contamination.

Natural orifice transluminal endoscopic surgery: where are we going?

The foundation for natural orifice transluminal endoscopic surgery (NOTES) is to access the peritoneal and other body cavities through the wall of the alimentary tract via natural orifices, with the goal of performing procedures within the peritoneum and other cavities, without the need to make incisions in the abdominal wall. We have made great progress in the field of NOTES since the publication of the White Paper in 2006. There are still major fundamental goals as outlined by the Society of American Gastrointestinal and Endoscopic Surgeons/American Society for Gastrointestinal Endoscopy joint committee that need to be evaluated and answered before NOTES is ready for widespread clinical use. These include prevention of infection, instrument development, creation of a multitasking platform, and the ability to recognize and treat intraperitoneal complications such as hemorrhage and other physiological adverse events. In response to this need, recent abstracts and papers have focused on the management of intraoperative complications. The next phase is to focus on controlled prospective multicenter clinical trials that compare defined NOTES procedure to standard laparoscopy. The goal is to produce reliable and convincing data for the United States Food and Drug Administration, insurance companies, the physician community and the general public. At the present time, we still have many important milestones that still need to be met. Most investigators agree that a hybrid technique and not a pure NOTES practice should be advocated until devices can meet the current and new challenges in this field.

Transvaginal cholecystectomy by using a prototype flexible clip applier.

BACKGROUND: Currently, no endoscopic clips have been proven to be effective in ligating the cystic duct in natural orifice transluminal endoscopic surgery (NOTES) hybrid cholecystectomy. OBJECTIVE: To determine the safety and feasibility of a prototype endoscopic flexible clip applier, which is the only flexible device that deploys a zero-gap clip. DESIGN: Pilot study in a survival porcine model. Necropsy was performed at 2 weeks postprocedure. SETTING: University of Missouri animal laboratory, Columbia, Missouri. INTERVENTION: Transvaginal cholecystectomy was performed on 6 survival pigs using the NOTES Toolbox 1.0. MAIN OUTCOME MEASUREMENTS: Safety and feasibility of the described instrument. Investigators were asked to fill out a standardized, blinded questionnaire on the ease of use and functionality of the flexible clip applier. RESULTS: Clipping of the cystic duct was achieved with the flexible clip applier in all 6 pigs. The mean time for completion of clipping of the cystic duct was 9 minutes. Multiple attempts were required to successfully fire the clip in 2 of 6 pigs. We were unable to visualize the tip of the clip before deployment. Difficulty releasing the clip from the applier once fired and challenges in clip loading were encountered. The clips were visualized in place at necropsy, with no bile leakage, evidence of infection, or injury to surrounding structures seen in any cases. LIMITATIONS: Preclinical animal model. CONCLUSION: The prototype flexible clip applier showed adequate safety and was feasible in clipping the cystic duct in all animals. Design efforts to improve clip visualization, loading, and release are underway.

Global Assessment of Gastrointestinal Endoscopic Skills (GAGES): a valid measurement tool for technical skills in flexible endoscopy.

BACKGROUND: Simulators may improve the efficiency, safety, and quality of endoscopic training. However, no objective, reliable, and valid tool exists to assess clinical endoscopic skills. Such a tool to measure the outcomes of educational strategies is a necessity. This multicenter, multidisciplinary trial aimed to develop instruments for evaluating basic flexible endoscopic skills and to demonstrate their reliability and validity. METHODS: The Global Assessment of Gastrointestinal Endoscopic Skills (GAGES) Upper Endoscopy (GAGES-UE) and Colonoscopy (GAGES-C) are rating scales developed by expert endoscopists. The GAGES scale was completed by the attending endoscopist (A) and an observer (O) in self-assessment (S) during procedures to establish interrater reliability (IRR, using the intraclass correlation coefficient [ICC]) and internal consistency (IC, using Cronbach's alpha). Instrumentation was evaluated when possible and correlated with total scores. Construct and external validity were examined by comparing novice (NOV) and experienced (EXP) endoscopists (Student's t-test). Correlations were calculated for GAGES-UE and GAGES-C with participants who had performed both. RESULTS: For the 139 completed evaluations (60 NOV, 79 EXP), IRR (A vs. O) was 0.96 for GAGES-UE and 0.97 for GAGES-C. The IRR between S and A was 0.78 for GAGES-UE and 0.89 for GAGES-C. The IC was 0.89 for GAGES-UE, and 0.95 for GAGES-C. There were mean differences between the NOV and the EXP endoscopists for GAGE-UE (14.4 +/- 3.7 vs. 18.5 +/- 1.6; p < 0.001) and GAGE-C (11.8 +/- 3.8 vs. 18.8 +/- 1.3; p < 0.001). Good correlation was found between the scores for the GAGE-UE and the GAGE-C (r = 0.75; n = 37). Instrumentation, when performed, demonstrated correlations with total scores of 0.84 (GAGE-UE; n = 73) and 0.86 (GAGE-C; n = 45). CONCLUSIONS: The GAGES-UE and GAGES-C are easy to administer and consistent and meet high standards of reliability and validity. They can be used to measure the effectiveness of simulator training and to provide specific feedback. The GAGES results can be generalized to North American and European endoscopists and may contribute to the definition of technical proficiency in endoscopy.

How should we establish the clinical case numbers required to achieve proficiency in flexible endoscopy?

BACKGROUND: Recommended procedure numbers for upper endoscopy (UE) and colonoscopy (C) are 35 and 50 for surgical residents, and 130 and 140 for gastroenterology fellows, respectively. The purpose of this study was to challenge the methods used to determine proficiency in flexible endoscopy. METHODS: Global assessment of gastrointestinal endoscopic skills (GAGES) was used to evaluate 139 procedures. Scores for UE were compared using self-reported case numbers and grouped according to requirements for each discipline. C scores were compared using the requirements to define novice and experienced endoscopists. Procedure volumes were plotted against GAGES scores. RESULTS: Three groups were compared for UE based on case volumes: fewer than 35 cases (group 1), 35 to 130 cases (group 2), and more than 130 cases (group 3). There was no difference between group 2 (17.8 +/- 1.8) and group 3 (19.1 +/- 1.1), but both scored higher than group 1 (14.4 +/- 3.7; P < .05). For C, the scores were 11.8 +/- 3.8 (novices) and 18.8 +/- 1.34 (experienced; P < .001) at a 50-case minimum and 12.4 +/- 4.2 and 18.8 +/- 1.3 (P < .001) for a 140-case proficiency cut-off level, respectively. The curve of procedures versus GAGES plateaued at 50 (UE) and 75 (C). CONCLUSIONS: The surgical and gastroenterology case recommendations may not represent the experience needed to achieve proficiency. GAGES scores could help define proficiency in basic endoscopy.

Pilot data on the endoscopic placement of covered metal stents to treat gastrojejunal leaks in a porcine model.

BACKGROUND: Placement of stents may be an alternative option to treat gastrojejunal (GJ) anastomotic leaks after Roux-en-Y gastric bypass (RYGB) surgery. The aim was to evaluate the performance of a covered metal stent (Alimaxx-E, 18 x 100 mm) across a GJ leak in a porcine model. METHODS: In eight pigs, a RYGB was performed and a 1-cm leak was created. A retrogastric and anterogastric GJ was performed equally with four pigs in each group. Stents were placed across the GJ anastomosis using endoscopy and fluoroscopy. The endpoints were position of the stents, healing of the leak, and complications at necropsy. RESULTS: Stent placement was feasible in all pigs it was attempted. In the retrogastric GJ group, pigs without stents survived 2 weeks without complications. Two pigs with stents died on postoperative days (PODs) 4 and 5. In the anterogastric GJ group, one pig with one stent survived 2 weeks with healing of the leak but with stent migration into the Roux limb. The remaining three pigs died between PODs 4 and 6. Pressure necrosis of the Roux limb caused by the distal end of the stent was found in all. CONCLUSIONS: Placement of fully covered metal stents is feasible. The use of small pigs with a thin small bowel wall in combination with relatively large stents was most likely the reason for complications found in all stented animals. Further studies of GJ leaks using these stents will require larger pigs or a different species.

Single-incision laparoscopic cholecystectomy using conventional instruments: early experience in comparison with the gold standard.

BACKGROUND: The aim of this pilot study was to describe our initial experience with single-incision laparoscopic cholecystectomy (SILC) using conventional laparoscopic equipment in comparison with concurrent patients undergoing conventional multiincision laparoscopic cholecystectomy. STUDY DESIGN: During the 7-month study period, data from all consecutive patients undergoing SILC by two surgeons were retrospectively analyzed and compared with data from patients undergoing conventional laparoscopic cholecystectomy by the same surgeons during the same time period. Outcomes measures included completion rate of attempted SILC, operative time, length of hospital stay, postoperative pain, and assessment of complications. RESULTS: From 51 laparoscopic cholecystectomies performed during the study period, 29 were attempted using single-incision technique and 22 were performed using the conventional four incisions. Of the attempted SILC cases, 14 (48%) were successfully completed, with the remainder requiring one to three additional skin incisions. There were no conversions to open in either group. Operative time was significantly longer in SILC cases compared with conventional laparoscopic cholecystectomy (85 versus 67 minutes; p = 0.01). There was a tendency toward greater postoperative pain in the SILC group. No substantial difference in complications was identified. CONCLUSIONS: SILC using conventional laparoscopic instrumentation is an effective alternative to standard four-incision laparoscopic cholecystectomy in selected patients. Development of a standardized technique and additional experience is needed for more consistent success. Additional studies of SILC are needed to demonstrate safety, define selection criteria, and determine any benefits over conventional laparoscopic cholecystectomy.

Laparoscopic transperitoneal repair of flank hernias: a retrospective review of 27 patients.

INTRODUCTION: Incisional hernias of the flank are rare with scattered case reports regarding the feasibility of laparoscopic treatment. Treatment can be technically challenging due to patient positioning and adequate mesh overlap and fixation. The aim of this study is to describe the surgical technique and present outcomes of the largest known case series of laparoscopic repair of flank hernia. METHODS: A retrospective chart review was performed from April 2002 to August 2006 at two university hospitals utilizing three surgeons' experience. All patients who underwent a laparoscopic repair of a flank hernia were identified and reviewed with regards to short-term outcomes. RESULTS: Twenty-seven patients were identified with incisional flank hernia treated laparoscopically. Average defect size was 188 cm(2) repaired with an average mesh size of 650 cm(2). Mean operating room (OR) time was 144 min and mean length of stay (LOS) was 3.1 days. There were two reoperations within the cohort: one for a new, unrelated midline hernia 7 months after repair of the initial flank hernia and one for chronic pain with removal of a previously placed polypropylene mesh in the subcutaneous tissue of the abdominal wall. Neither patient had failure of the laparoscopic flank hernia repair. Two other patients were conservatively treated for chronic pain. Mean follow-up was 3.6 months. CONCLUSIONS: In the laparoscopic repair of flank hernias adequate retroperitoneal dissection and wide mesh overlap is imperative. Laparoscopic repair can be performed safely and effectively with good short-term outcomes.

Transgastric placement of biologic mesh to the anterior abdominal wall.

BACKGROUND: Incisional hernia repairs have a risk of wound complications that may be decreased using a natural orifice transluminal endoscopic surgery (NOTES) approach. The aim of this study was to determine the feasibility and safety of transgastric mesh placement to the anterior abdominal wall in a porcine model as a precursor to future studies of NOTES ventral hernia repair. METHODS: The procedure was done under sterile conditions with a double lumen endoscope using a plastic overtube. The endoscope was placed in the stomach preloaded with an overtube. Entrance of the endoscope and overtube into the peritoneal cavity was performed with the percutaneous endoscopic gastrostomy (PEG) technique. A 13 x 15 cm Surgisis Gold mesh with four corner sutures was delivered through the overtube. Transfascial suture passer and endoscopic grasper were used to externalize the sutures and attach the mesh to the anterior abdominal wall. The gastrotomy was closed with a transabdominal gastropexy. The pigs were sacrificed at 2 weeks. RESULTS: Mesh placement was performed in five pigs. Operative time was 215 min (standard deviation, SD 99 min). The most difficult portion of the procedure involved manipulating the gastric overtube, likely exposing the mesh to bacteria in the stomach. Culture-positive abscesses were present at the mesh in 3/5 animals. The mesh appeared intact in 4/5 animals; one of the infected meshes had delamination of 50% of the mesh. Adhesions to the mesh surface varied from 2% to 100%. At 2 weeks, median mesh size was 116 cm2 (range 96-166 cm2) and median contraction was 41% (range 15-51%). Histologic evaluations demonstrated marked inflammation and fibrosis progressing into the mesh material. CONCLUSIONS: Totally endoscopic transgastric delivery and fixation of a biologic mesh to the anterior abdominal wall is feasible. Challenges remain in designing systems for mesh delivery that exclude gastric content. Once these problems can be surmounted NOTES ventral hernia repair may become an option in man.

Laparoscopic appendectomy--is it worth the cost? Trend analysis in the US from 2000 to 2005.

BACKGROUND: Although laparoscopic appendectomy is widely used for treatment of appendicitis, it is still unclear if it is superior to the open approach. STUDY DESIGN: From the Nationwide Inpatient Sample 2000 to 2005, hospitalizations with the primary ICD-9 procedure code of laparoscopic (LA) and open appendectomy (OA) were included in this study. Outcomes of length of stay, costs, and complications were assessed by stratified analysis for uncomplicated and complicated appendicitis (perforation or abscess). Regression methods were used to adjust for covariates and to detect trends. Costs were rescaled using the hospital and related services portion of the Medical Consumer Price Index. RESULTS: Between 2000 and 2005, 132,663 (56.3%) patients underwent OA and 102,810 (43.7%) had LA. Frequency of LA increased from 32.2% to 58.0% (p < 0.001); conversion rates decreased from 9.9% to 6.9% (p < 0.001). Covariate adjusted length of stay for LA was approximately 15% shorter than for OA in both uncomplicated and complicated cases (p < 0.001). Adjusted costs for LA were 22% higher in uncomplicated appendicitis and 9% higher in patients with complicated appendicitis (p < 0.001). Costs and length of stay decreased over time in OA and LA. The risk for a complication was higher in the LA group (p < 0.05, odds ratio=1.07, 95% CI 1.00 to 1.14) with uncomplicated appendicitis. CONCLUSIONS: LA results in higher costs and increased morbidity for patients with uncomplicated appendicitis. Nevertheless, LA is increasingly used. Patients undergoing LA benefit from a slightly shorter hospital stay. In general, open appendectomy may be the preferred approach for patients with acute appendicitis, with indication for LA in selected subgroups of patients.

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.

Laparoscopic Nissen fundoplication is a good option in patients with abnormal esophageal motility.

BACKGROUND: Patients with gastroesophageal reflux disease (GERD) and abnormal esophageal motility are the most controversial subgroup of surgically treated patients because of potentially increased risk of postoperative dysphagia. Our study aim was to determine if Nissen fundoplication is associated with increased postoperative dysphagia in patients with ineffective esophageal motility. METHODS: Medical records of all adult (>18 years old) patients who underwent laparoscopic Nissen fundoplication for GERD over 8 years were reviewed retrospectively. Of the 151 patients, 28 (group A) met manometric criteria for abnormal esophageal motility (<30 mmHg mean contractile pressure or <80% peristalsis), whereas 63 (group B) had normal esophageal function. Sixty patients had no manometric data and were therefore excluded from analysis. Follow-up time ranged from 1 month to 5 years. Outcomes (postoperative dysphagia, recurrence of GERD symptoms, free of medications) were compared between groups. RESULTS: Group A had higher age and American Society of Anesthesiologists (ASA) score (p = 0.016 and 0.020), but this did not correlate with outcome. Two patients (7.1%) in group A and three patients (5.3%) in group B had postoperative dysphagia. When adjusted for follow-up time, there was no significant difference between the groups (p = 0.94). Group B had more cases of recurrent heartburn (10.7% versus 3.6%, p = 0.039), and more patients in this group were back on medications (21.4% versus 7.1%, p < 0.05) CONCLUSIONS: This retrospective study found equally low rates of dysphagia following Nissen fundoplication regardless of baseline esophageal motility. Preoperative esophageal dysmotility therefore does not seem to be a contraindication for laparoscopic Nissen fundoplication.

Transgastric cholecystectomy using a prototype endoscope with 2 deflecting working channels (with video).

BACKGROUND: Transgastric cholecystectomy has been shown to be feasible in animal models and human case reports but cumbersome with current available instrumentation. OBJECTIVE: To evaluate a prototype endoscope with 2 working channels with deflectors at the distal tip for performance of transgastric cholecystectomy. DESIGN: Animal study, nonsurvival and survival. ANIMALS: Sixteen male pigs. SETTING: University hospital. INTERVENTION: Transgastric cholecystectomy in 6 nonsurvival pigs by using several different dual-channel endoscopes and 10 survival pigs by using the Olympus dual-channel endoscope with an up-down deflecting channel to the left of the objective lens and a left-right deflecting channel located below the lens. Gallbladder fundic retraction was performed with the aid of one laparoscopic grasper. RESULTS: Cholecystectomy was successful in all survival animals. Median procedure time was 81 minutes (range 31-163 minutes), with a decrease over time. Visualization of all structures was achieved, and clipping of the cystic duct and artery was successful in all cases. Dissection of the gallbladder via the left-right channel was enhanced with retraction via the up-down deflecting channel. Nine of 10 animals survived without complications. One animal died, on postoperative day 2, secondary to peritonitis due to a leak from the gastrotomy site. CONCLUSIONS: This endoscope, with deflecting working channels, allows transgastric cholecystectomy in pigs. The endoscope was stable enough to be used without an overtube and facilitated retraction and dissection. This endoscope is promising for use in transgastric cholecystectomy in human beings.

Lessons learned establishing an animal model for endoscopic stent placement to treat gastrojejunal anastomotic leaks after gastric bypass.

BACKGROUND: Anastomotic leaks after Roux-en-Y gastric bypass (RYGB) cause significant morbidity and mortality. Placement of enteral stents may be an improvement to the current treatment, which is withholding of oral intake and total parenteral nutrition. METHODS: We established an open RYGB porcine model with a leak at the gastrojejunostomy in three pigs. A pilot study was then performed in five pigs, where Polyflex stents were placed across the leaking anastomosis and fixed with transmural sutures to the Roux limb. After 2 weeks, endoscopy, fluoroscopy, and necropsy were performed. RESULTS: One pig without stent died on the second postoperative day (POD) due to a volvulus unrelated to the leak. In the other two pigs, leaks with large abscesses were found at necropsy. Stents were placed in five pigs but required open surgical manipulation of the delivery system. One pig died on POD 3 due to a perforation in the posterior gastric wall likely caused by the rigid delivery system. One pig died from gastrojejunostomy leakage on POD 5. The leaks were healed in the remaining three pigs after 2 weeks. In one pig, a perforation of the jejunum 4 cm distal to the anastomosis was found. Stent migration to some extent was seen in all pigs. CONCLUSION: Stent placement and fixation were feasible but had a high complication rate for treatment of a leaking gastrojejunal anastomosis in the open porcine model. The stent may have contributed to healing the leak in some pigs. Further studies should focus on improving stent delivery, sealing of the leak, and prevention of stent migration.

Placement of a covered polyester stent prevents complications from a colorectal anastomotic leak and supports healing: randomized controlled trial in a large animal model.

BACKGROUND: Anastomotic leaks after colorectal operation continue to be a significant cause of morbidity. A covered endoluminal stent could seal a leak and eliminate the need for diversion. The aim of this study was to test the efficacy of a temporary covered stent to prevent leak related complications. METHODS: Sixteen adult pigs (80-120 lbs) underwent open transection of the rectosigmoid followed by anastomosis with a circular stapler. Eight animals (study group) underwent endoscopic placement of a 21-mm covered polyester stent. Eight control group animals were left without stents. In all animals, a 2-cm leak was created along the anterior portion of the anastomosis. The animals were killed after 2 weeks and evaluated for abdominal infection, fistulae, and adhesions. The anastomosis was excised and the following parameters were assessed by a pathologist blinded to treatment: mucosal interruption (mm), inflammatory response, collagen type I and III, granulation, and fibrosis (grade 0-4). RESULTS: Stents were spontaneously expelled between postoperative days 6 and 9. At necropsy, none of the animals in the study group had leak related complications, whereas in the control group, 5 (63%) developed intraabdominal infection (4 abscesses, 1 fistula) at the anastomosis (P = .002). Dense adhesions to the anastomosis were found in 7 (88%) control animals. On histology, anastomotic sites in the study group had significantly less mucosal interruption and granulation. Two pigs in the study group died on postoperative day 7, one due to evisceration and one from bladder necrosis. The mortality result is not different from controls (P = .47), both events seem to be unrelated to stent placement. CONCLUSION: Temporary placement of a covered polyester stent across a colorectal anastomosis prevents leak-related complications and supports the healing of anastomotic leaks.

Nationwide impact of laparoscopic lysis of adhesions in the management of intestinal obstruction in the US.

BACKGROUND: Treatment of adhesion-related complications is cost intensive and presents a considerable burden to the health care system. The objective of this study was to compare open (OLA) and laparoscopic lysis of adhesions (LLA) in the treatment of intestinal obstruction, based on a nationwide representative sample. STUDY DESIGN: Patients with intestinal obstruction undergoing OLA, LLA, and conversion were identified from the 2002 National Inpatient Sample. After propensity methods were used to adjust for covariates including patient demographics, hospital characteristics, and comorbidities, the impact of OLA and LLA was analyzed concerning in-hospital mortality, postoperative complications, length of stay (LOS), and in-hospital costs. RESULTS: Of 6,165 patients, 88.6% underwent OLA and 11.4% had LLA. Conversion was required in 17.2% of LLA patients. Unadjusted mortality was equal between LLA and conversion (1.7%) and half the rate compared with OLA (3.4%) (p = 0.014). After adjusting with propensity methods, the odds of complications in the LLA group (intention to treat) were 25% less than in the OLA (p = 0.008). The LLA group had a 27% shorter LOS (p = 0.0001) and was 9% less expensive than the OLA group (p = 0.0003). There was no statistical significant difference for LOS, complications, and costs between the conversion and OLA groups. CONCLUSIONS: Results from this study suggest that when LLA is applied to selected patients with intestinal obstruction, there are reductions in postoperative complications, LOS, and costs. Prospective studies are needed to confirm these data and better identify the subgroup of patients who have improved outcomes with LLA.