Enhanced recovery outcomes following per-oral pyloromyotomy (POP): a comparison of safety and cost with same-day discharge versus inpatient recovery.

BACKGROUND: While per-oral pyloromyotomy (POP) has shown promise as a novel endoscopic procedure to treat medically refractory gastroparesis, standardized care pathways are not well-defined. We aimed to compare the safety and cost of same-day discharge (SDD) after POP with inpatient stay overnight or longer. METHODS: All patients with SDD after POP between January 2016 and May 2018 were retrospectively identified from a prospectively maintained registry. Propensity scores considering gender, age, gastroparesis etiology, and American Society of Anesthesiologists (ASA) class were used to match a comparison group which stayed overnight or longer. Statistical tests included two-sample t tests for continuous variables, Fisher's exact test for categorical variables, and paired sample t tests for within-group comparisons with repeated measures. RESULTS: Fifty-four patients who underwent POP with SDD during the study period were propensity-matched with 54 patients with inpatient recovery. The SDD cohort was 85.2% female with a mean age of 44.8 years and median ASA class 3. The etiology of gastroparesis was idiopathic in 53.7% (n = 29), diabetic in 29.6% (n = 16), and post-surgical in 11.1% (n = 6). Operative time was shorter in the SDD cohort (25.4 vs. 31.3 min, p = 0.02). The mean post-procedure recovery time was 4 h in patients with SDD and 29.3 h in the inpatient cohort (p < 0.001). There was a trend towards less readmissions with SDD (7.4% vs. 18.5%, p = 0.08). There was no increased risk of complications with SDD (1.9% vs. 3.7%, p = 0.57). Compared to inpatient recovery, the average total cost for the procedure, recovery, and all subsequent care within 30 days was 26.0% less with SDD (p < 0.001). CONCLUSIONS: Following POP, patients can be safely discharged the same day with low risk of both complications and readmission. Total costs in the complete perioperative period are significantly less with SDD compared to inpatient recovery.

Laparoscopic pyloroplasty versus endoscopic per-oral pyloromyotomy for the treatment of gastroparesis.

BACKGROUND: Gastroparesis is a debilitating functional disorder of the stomach characterized by delayed gastric emptying absent an obstructive etiology. Surgical or endoscopic disruption of the pylorus has been utilized to treat this disease, but there is little evidence comparing laparoscopic pyloroplasty (LP) with endoscopic per-oral pyloromyotomy (POP). Herein we describe our experience at our institution using a propensity-matched cohort study to compare outcomes between these procedures. METHODS: All patients who underwent LP for the treatment of gastroparesis from October 2014 through September 2017 at our institution were retrospectively reviewed. Propensity scoring was used to match these patients 1:1 to patients undergoing POP during this time period based on gender, age, and etiology of gastroparesis. Symptom scores using the Gastroparesis Cardinal Symptom Index (GCSI), scintigraphic gastric emptying studies (GES), and perioperative outcomes were compared between matched cohorts. Thirty patients underwent LP for gastroparesis during the study period which were matched 1:1 with patients undergoing POP. The etiology of gastroparesis was 63.3% idiopathic (n = 19), 20.0% post-surgical (n = 6), and 16.7% diabetic (n = 5) in both cohorts. RESULTS: Patients who underwent LP had a longer average length of stay (4.6 vs. 1.4 days, p = 0.003), operative time (99.3 vs. 33.9 min, p < 0.001), and estimated blood loss (12.9 vs. 0.4 mL, p < 0.001). There were more complications in the LP cohort (16.7 vs. 3.3%, p = 0.086), which included surgical site infection (6.7 vs. 0%, p = 0.153), pneumonia (6.7 vs. 0.0%, p = 0.153), and unplanned ICU admission (10.0 vs. 0.0%, p = 0.078). LP and POP both resulted in similar, significant improvements in both in GCSI scores and objective gastric emptying. CONCLUSIONS: Per-oral endoscopic pyloromyotomy (POP) is safe and effective for the treatment of medical refractory gastroparesis. POP has less perioperative morbidity compared to LP with comparative functional outcomes.

Per-oral Pyloromyotomy (POP) for Medically Refractory Gastroparesis: Short Term Results From the First 100 Patients at a High Volume Center.

OBJECTIVE: For patients with gastroparesis, temporary pyloric disruption has been shown to improve symptoms and gastric emptying. Per-oral pyloromyotomy (POP) is an innovative endoscopic procedure to divide the pylorus from within a submucosal tunnel, as a corollary to surgical pyloromyotomy. Here we evaluate subjective and objective outcomes 12-weeks after POP at a high volume center. METHODS: The first 100 consecutive patients undergoing POP were included, with procedure dates between January 2016 and October 2017. Patients were evaluated using the Gastroparesis Cardinal Symptom Index (GCSI), and 4-hour solid-phase scintigraphic gastric emptying studies (GES) prior to procedure and at 90 days post-POP RESULTS:: The study cohort was 85% female with a mean age of 45.0 ±â€Š14.6 years. Gastroparesis etiologies were divided among idiopathic (56%), diabetic (21%), postsurgical (19%), and other in 4%. There were 67% of the patients who had previous endoscopic or surgical interventions for gastroparesis. Most POP procedures were performed in the operating room (97%) and were completed in an average of 33 minutes. Ten patients incurred complications (10%), which included 1 diagnostic laparoscopy and 2 cases of gastrointestinal bleeding. Overall GCSI improved from a preoperative mean of 3.82 ±â€Š0.86 to 2.54 ±â€Š1.2 (P < 0.001). The improvement in each GCSI subscore was also highly statistically significant. Among the patients with postoperative GES available, 78% had objectively better 4-hour emptying with a mean improvement in retention by 23.6% (P < 0.001). This included 57% of patients with normal gastric emptying post-POP. CONCLUSION: For patients with medically refractory gastroparesis, POP results in both subjective and objective improvement in the majority of patients. Prior intervention does not obviate POP as a therapeutic option. POP should be included along the treatment algorithm for patients with gastroparesis as an organ-sparing procedure.

Comparison of laparoscopic jejunostomy tube to percutaneous endoscopic gastrostomy tube with jejunal extension: long-term durability and nutritional outcomes.

INTRODUCTION: Enteral access through the jejunum is indicated when patients cannot tolerate oral intake or gastric feeding. While multiple approaches for feeding jejunal access exist, few studies have compared the efficacy of these techniques. The purpose of this study was to investigate the long-term durability, re-intervention rates, and nutritional outcomes following percutaneous endoscopic gastrostomy tubes with jejunal extension tubes (PEG-JET) versus laparoscopic jejunostomy tubes (j-tubes). METHODS: Retrospective chart review was performed on all patients who underwent PEG-JET or laparoscopic jejunostomy tube placement from January 2005 through December 2015 at our institution. Thirty-day and long-term outcomes were compared between the two groups. RESULTS: A total of 105 patients underwent PEG-JET and 307 patients underwent laparoscopic j-tube placement during the defined study period. In terms of 30-day outcomes, patients who underwent PEG-JET placement were significantly more likely to experience a tube dislodgement event (p = 0.005) and undergo a re-intervention (p < 0.001). Patients who had a laparoscopic j-tube placed were significantly more likely to meet their enteral feeding goals (p = 0.002) and less likely to require nutritional supplementation with total parenteral nutrition (TPN) (p < 0.001). With regard to long-term outcomes, patients who underwent PEG-JET placement were significantly more likely to experience tube occlusion (p < 0.001) and require an endoscopic or surgical tube re-intervention (p < 0.001). Patients who underwent laparoscopic j-tube placement were significantly more likely to experience a tube site leak (p = 0.015) but were less likely to require nutritional supplementation with TPN (p = 0.001). CONCLUSION: Laparoscopic jejunostomy tubes provide more durable long-term enteral access compared to PEG-JET. Consideration should be given to laparoscopic jejunostomy tube placement in eligible patients who cannot tolerate oral intake or gastric enteral feeding.

Per oral endoscopic pyloromyotomy for refractory gastroparesis: initial results from a single institution.

INTRODUCTION: Gastroparesis is a debilitating disease characterized by delayed gastric emptying in the absence of mechanical obstruction. A new intramural technique, per oral endoscopic pyloromyotomy (POP), has been proposed as an alternative to surgical pyloroplasty for the management of medical refractory gastroparesis. Herein, we detail the short-term results of POP at our institution. METHODS: POP was first performed at our institution in January 2016. All patients undergoing POP for management of gastroparesis from January 2016 through January 2017 were prospectively followed. All patients underwent a 4-h, non-extrapolated gastric emptying scintigraphy study and were asked to rate their symptoms using the Gastroparesis Cardinal Symptom Index (GCSI) at their pre-procedure visit and at 3 months post-procedure. RESULTS: A total of 47 patients underwent POP during the defined study period. Twenty-seven (57.4%) patients had idiopathic gastroparesis, 12 (25.6%) had diabetic gastroparesis, and eight (17.0%) had post-surgical gastroparesis. Forty-one (87.2%) patients had at least one previous intervention (i.e., enteral feeding tube, gastric pacer, botox injection) for their gastroparesis symptoms. All patients had evidence of gastroparesis on pre-procedure gastric emptying studies. The average length of hospital stay was 1 day. One patient died within 30-days of their index procedure which was unrelated to the procedure itself. The average pre-procedure percentage of retained food at 4 h was 37% compared to an average post-procedure percentage of 20% (p < 0.03). The average pre-procedure GCSI score was 4.6 compared to an average post-procedure GCSI of 3.3 (p < 0.001). CONCLUSIONS: POP is a safe and feasible endoscopic intervention for medical refractory gastroparesis. Additional follow-up is required to determine the long-term success of this approach in alleviating gastroparesis symptoms.

Long-term outcomes of combined endoscopic/laparoscopic intragastric enucleation of presumed gastric stromal tumors.

PURPOSE: Definitive surgical treatment of gastric myogenic neoplasms such as gastrointestinal stromal tumors (GISTs) typically involves full-thickness resection of the lesion with normal gastric wall as the margin. This is not readily possible with proximal gastric lesions near the gastroesophageal junction, nor necessary for small incidental lesions. We have employed a combined endoscopic/laparoscopic intraluminal enucleation technique for selected patients and report long-term surveillance following this novel technique. METHODS: Retrospective review of patients who have undergone intraluminal laparoscopic resection from 1994 to 2008. RESULTS: Fifteen patients who underwent intraluminal enucleation were followed up for a median of 61 months. There were eight men and seven women with a mean age of 62.1 ± 3.38 years. Eight patients (53 %) underwent endoscopy for gastrointestinal bleeding, six for dyspepsia (40 %), six for anemia (40 %), and four for abdominal pain (27 %). Eight lesions (53 %) were located in the fundus/cardia: six (40 %) in the body and two (13 %) in the antrum. The mean tumor size was 3.5 ± 0.45 (1.5-7.0) cm. GIST lesions with benign histologic features predominated. All operations were successfully completed, including full-thickness resections with no conversion to open procedure, major morbidity, or mortality. Complete endoscopic and endosonographic surveillance was accomplished in 14 patients with no local or distant recurrence and no symptomatic follow-up in any patient. CONCLUSION: Enucleation of intact gastrointestinal stromal tumors can be accomplished with low risk of recurrence when done with a combined endoscopic/laparoscopic intraluminal technique. It should be the preferred approach considered for small, proximal, intraluminal tumors.

Peroral endoscopic myotomy (POEM) leads to similar results in patients with and without prior endoscopic or surgical therapy.

INTRODUCTION: Traditional treatment for the esophageal motility disorder, achalasia, ranges from endoscopic botulinum toxin (Botox) injections or balloon dilatation, to laparoscopic or open surgical myotomy. Recent advances in endoscopic therapy have led to peroral endoscopic myotomy (POEM) as a viable alternative to traditional techniques for myotomy. Uncertainty exists as to whether the procedure is feasible for patients who have already received prior endoscopic or surgical procedures for therapy, as these groups experience higher failure rates as well as intraoperative mucosal perforations and technical difficulty during Heller myotomy. We describe our first 40 patients who have undergone POEM and compare outcomes between patients who have or have not received previous treatment for achalasia. METHODS AND PROCEDURES: We evaluated our prospectively collected database of POEM procedures performed by two surgeons (JLP and JMM) at a single institution. Perioperative data was collected for operative and hospital outcomes. Patients completed pre- and postoperative GERD-Health-Related Quality of Life Questionnaires (GERD-HRQL) and SF-12 surveys for symptom scoring. RESULTS: Forty patients received a POEM procedure between 2011 and 2013. Of these, 40% (n = 16) had had at least one prior endoscopic or surgical procedure. Nine had prior Botox injections, 7 had balloon dilations, 3 had both Botox and dilations, and 3 received prior laparoscopic Heller myotomy (two with Dor fundoplication). Mean operative time was 102 min for patients with prior procedures (Prior Tx) and 118 min for patients without any prior procedure (No Tx) (p = 0.07). Intraoperative complication rates for the Prior Tx group were 12.5 versus 16.7% for the No Tx group. Mean follow-up was 10 months. Both groups independently demonstrated clinical improvement in both the GERD-HRQL and SF-12 scores following POEM. There were no statistical differences between the two groups for GERD-HRQL reflux and dysphagia subset scores, or SF-12 mental component summary. CONCLUSION: We found favorable outcomes following POEM in patients who have had prior endoscopic or surgical treatments for achalasia, as well as for patients without prior intervention. There were no significant differences between these two groups with regards to operative times, GERD-HRQL scores, and mental component SF-12 scores. One complication requiring intervention occurred in a patient that had received multiple prior Botox injections and balloon dilatations. POEM appears to be a viable alternative for treatment of achalasia compared to traditional techniques, however, long-term data are needed to establish the durability of this technique and to determine whether symptoms will recur necessitating re-intervention.

Commercially available biological mesh does not prevent stricture after esophageal mucosectomy.

BACKGROUND AND STUDY AIMS: Endoscopic mucosal resection (EMR) offers a minimally invasive therapy for advanced esophageal dysplasia and early cancers but stricture formation limits its applicability. We aimed at assessing the efficacy of placement of a commercially available biological mesh for preventing stricture formation following esophageal EMR. METHODS: 25 swine were submitted to circumferential esophageal EMR with 10-cm extent and divided in five groups: one group with EMR only (control); one receiving an uncovered stent (stent-only group); and three groups receiving a stent covered with one of three extracellular matrices, namely small intestine submucosa (SIS group), acellular dermal matrix (ADM group), or urinary bladder matrix (UBM group). Stricture formation was evaluated with weekly esophagograms. RESULTS: The stent-only group had significantly less stricture formation and survival was extended compared with controls (4.8 vs. 2.4 weeks). Compared with stenting only, the addition of a biological mesh did not reduce stricture formation: percent reductions in esophageal diameter for the groups were SIS 86 %, ADM 94 %, and UBM 94 %, compared with 82 % in the stent-only group. CONCLUSIONS: Placement of commercially available biological meshes did not alter remodeling sufficiently to prevent stricture formation after esophageal EMR.

Retrograde myotomy: a variation in per oral endoscopic myotomy (POEM) technique.

BACKGROUND: Per oral endoscopic myotomy (POEM) has evolved as a novel therapeutic option for the treatment of esophageal motility disorders such as achalasia. The originally described dissection technique involves cutting the inner circular esophageal muscle fibers in an antegrade fashion. We have modified this technique by commencing the muscular division at the most distal aspect of the submucosal tunnel and continuing the dissection in a retrograde fashion. We present our initial series of patients performed using this modified technique. METHODS: We retrospectively reviewed our prospectively collected database. Peri- and postoperative data were collected and analyzed. POEM procedures were performed in a near-identical manner as previously published. RESULTS: Retrograde myotomy was performed on five patients with a diagnosis of achalasia. Four had a history of prior treatment including balloon dilation, with one of these having a prior surgical myotomy. Retrograde POEM procedures were performed with trace blood loss and without any complications. Mean operative time was 85 min. All patients had normal esophagram studies, and diets were advanced as per protocol. CONCLUSION: POEM was developed as a minimally invasive method for the treatment of achalasia. Our retrograde dissection modification allows the most critical portion of the case, namely division of the lower esophageal and upper gastric circular muscle fibers, to be performed earlier in the case. This ensures adequate dissection of the primary site of esophageal dysfunction should problems arise during the procedure. The modification is straightforward, without the need for additional training or equipment, and appears to provide a more rapid myotomy with less charring in this small cohort of patients.

Preliminary results of antiscarring therapy in the prevention of postendoscopic esophageal mucosectomy strictures.

BACKGROUND: Esophageal endoscopic submucosal dissection (ESD) is an effective minimally invasive therapy for early esophageal cancer and high-grade Barrett dysplasia. However, esophageal stricture formation after circumferential or large ESD has limited its wide adoption. Mitomycin C (MMC), halofuginone (Hal), and transforming growth factor ß3 (TGF-ß3) exhibits antiscarring effects that may prevent post-ESD stricture formation. METHODS: Using endoscopic mucosectomy (EEM) technique, an 8- to 10-cm-long circumferential esophageal mucosal segment was excised in a porcine model. The site was either untreated (control, n = 6) or received 40 evenly distributed injections of antiscarring agent immediately and at weeks 1 and 2. High and low doses were used: MMC 5 mg (n = 2), 0.5 mg (n = 2); Hal 5 mg (n = 2), 1.5 mg (n = 2), 0.5 mg (n = 2); TGF-ß3 2 µg (n = 2), 0.5 µg (n = 2). The degree of stricture formation was determined by the percentage reduction of the esophageal lumen on weekly fluoroscopic examination. Animals were euthanized when strictures exceeded 80 % or the animals were unable to maintain weight. RESULTS: The control group had a luminal diameter reduction of 78.2 ± 10.9 % by 2 weeks and were euthanized by week 3. Compared at 2 weeks, the Hal group showed a decrease in mean stricture formation (68.4 % low dose, 57.7 % high dose), while both TGF-ß3 dosage groups showed no significant change (65.3 % low dose, 76.2 % high dose). MMC was most effective in stricture prevention (53.6 % low dose, 35 % high dose). Of concern, the esophageal wall treated with high-dose MMC appeared to be necrotic and eventually led to perforation. In contrast, low dose MMC, TGF-ß3 and Hal treated areas appeared re-epithelialized and healthy. CONCLUSIONS: Preliminary data on MMC and Hal demonstrated promise in reducing esophageal stricture formation after EEM. More animal data are needed to perform adequate statistical analysis in order to determine overall efficacy of antiscarring therapy.

Biodegradable esophageal stent placement does not prevent high-grade stricture formation after circumferential mucosal resection in a porcine model.

BACKGROUND: Advanced esophageal dysplasia and early cancers have been treated traditionally with esophagectomy. Endoscopic esophageal mucosectomy (EEM) offers less-invasive therapy, but high-degree stricture formation limits its applicability. We hypothesized that placement of a biodegradable stent (BD-stent) immediately after circumferential EEM would prevent stricturing. METHODS: Ten pigs (five unstented controls, five BD-stent) were utilized. Under anesthesia, a flexible endoscope with a band ligator and snare was used to incise the mucosa approximately 20 cm proximal to the lower esophageal sphincter. A 10-cm, circumferential, mucosal segment was dissected and excised by using snare electrocautery. In the stented group, an 18-×120-mm, self-expanding, woven polydioxanone stent (ELLA-CS, Hradec-Kralove) was deployed. Weekly esophagograms evaluated for percent reduction in esophageal diameter, stricture length, and proximal esophageal dilation. Animals were euthanized when the stricture exceeded 80% and were unable to gain weight (despite high-calorie liquid diet) or at 14 weeks. RESULTS: The control group rapidly developed esophageal strictures; no animal survived beyond the third week of evaluation. At 2 weeks post-EEM, the BD-stent group had a significant reduction in esophageal diameter (77.7 vs. 26.6%, p < 0.001) and degree of proximal dilation (175 vs. 131%, p = 0.04) compared with controls. Survival in the BD-stent group was significantly longer than in the control group (9.2 vs. 2.4 weeks, p = 0.01). However, all BD-stent animals ultimately developed clinically significant strictures (range, 4-14 weeks). Comparison between the maximum reduction in esophageal diameter and stricture length (immediately before euthanasia) demonstrated no differences between the groups. CONCLUSIONS: Circumferential EEM results in severe stricture formation and clinical deterioration within 3 weeks. BD-stent placement significantly delays the time of clinical deterioration from 2.4 to 9.2 weeks, but does not affect the maximum reduction in esophageal diameter or proximal esophageal dilatation. The timing of stricture formation in the BD-stent group correlated with the loss radial force and stent disintegration.

Comparison of anterior transgastric access techniques for natural orifice translumenal endoscopic surgery.

BACKGROUND: The advancement of natural orifice translumenal endoscopic surgery (NOTES) into clinical practice is dependent on its safety, efficacy, and efficiency. Access is the obligatory first step in NOTES and serves as a surrogate to technical difficulties associated with this novel surgical approach. This study aimed to compare endoscopic transgastric access techniques in terms of safety, reproducibility, and efficiency. METHODS: Seven variations for anterior transgastric NOTES access were evaluated with female domestic swine. After marking of an anterior site, electrocautery was used to create a small gastrotomy, followed by balloon dilation and entry into the peritoneal cavity. Methodologic variations incorporated the use of guidewires, electrocautery and dilation combined within a single device, support tubes, and dilation without electrocautery. Access times were recorded, and tissue injury was evaluated. RESULTS: In 70 access attempts, the most serious complication was bleeding from the gastroepiploic vessel, controlled with electrocautery. High variability in access times was prevalent with almost all the access techniques. CONCLUSIONS: This study supports the presumption that an anterior transgastric access technique for NOTES procedures is safe. The use of a wire to mark the site and another wire to retain the gastrotomy provided safe, efficient, and reproducible transgastric access. Comparison with laparoscopy exposed the disparity in technical challenges facing NOTES, suggesting that new technology and further refinement in methodology are required for NOTES to be clinically relevant.

Endoscopic access to and exploration of the lesser sac in a human cadaver model: opportunity for transgastric endoscopic pancreatic surgery (with video).

BACKGROUND: Transgastric endoscopy may represent a viable platform for diagnostic and therapeutic pancreatic interventions with reduced morbidity. In a human cadaver model, we aimed to determine the feasibility of transgastric endoscopic access to the lesser sac, creation of an adequate working space within the lesser sac, and reliable identification of lesser sac anatomic structures. METHODS: In six human cadavers, endoscopic guidance was used to determine an appropriate access site to the lesser sac. Subsequently, endosonographic guidance was used to introduce an aspiration needle into the potential space between the stomach and the pancreas. After creating a fluid cushion and dilating the needle tract, an endoscope was advanced through the gastrotomy into the lesser sac and air insufflation was used to create a working space. Predetermined anatomic structures were systematically sought and marked when recognized. In the final two cadavers, endoscopic closure of the access site was performed. RESULTS: All six procedures were successful in achieving access to the lesser sac and establishing an adequate working space. The access sites appeared amenable to endoscopic closure. Reliable organ identification, however, was not achieved in all cases, representing one of the immediate barriers to clinical application. CONCLUSIONS: Transgastric endoscopic access to the lesser sac can be achieved reliably and an adequate working space can be established. Additional research addressing endoscopic orientation and organ recognition within the lesser sac is necessary. The immediate potential applications of this approach include differentiating benign from malignant pancreatic pathology.

Transgastric natural-orifice transluminal endoscopic surgery peritoneoscopy in humans: a pilot study in efficacy and gastrotomy site selection by using a hybrid technique.

BACKGROUND: Diagnostic natural-orifice transluminal endoscopic surgery (NOTES) peritoneoscopy can easily be performed with standard endoscopic equipment in animal studies. The efficacy and optimal transgastric site for NOTES access in humans, however, has not been determined. OBJECTIVE: To characterize the efficacy of various anterior gastric access locations for diagnostic transgastric NOTES peritoneoscopy in humans. DESIGN: Prospective clinical study. SETTING: Tertiary-care center with experience in NOTES peritoneoscopy. PATIENTS: Patients undergoing planned laparoscopic gastrectomy or gastrotomy involving the anterior aspect of the stomach were eligible. INTERVENTIONS: An anterior gastric site for NOTES gastrotomy was chosen and transgastric NOTES access was independently established after laparoscopic abdominal exploration. Peritoneoscopy was then performed. The site of gastrotomy was closed as part of the intended laparoscopic procedure. MAIN OUTCOME MEASURES: The ability to visualize the abdominal and pelvic organs in all four quadrants was determined. Patients were evaluated postoperatively for complications. RESULTS: Eight patients requiring 9 procedures were studied. Gastrotomy sites were classified as body (n = 3), lesser curvature (n = 3), greater curvature (n = 1), fundus (n = 1), and antrum (n = 1). Satisfactory navigation could only be performed to the right upper and both lower quadrants. The left upper quadrant, specifically the spleen, was adequately visualized in only 1 case (11%), where the gastrotomy site was at the greater curvature. One patient developed a surgical site infection requiring oral antibiotic therapy. The median postoperative stay was 2 days (range, 0-3 days). LIMITATIONS: Small number of patients. CONCLUSION: NOTES peritoneoscopy with a gastrotomy on the anterior stomach permits adequate visualization of organs in the right upper and both lower quadrants. Visualization of the left upper quadrant and spleen is, however, limited unless access is gained on the greater curvature of the stomach. The accuracy of NOTES in identifying intra-abdominal pathology compared with laparoscopy remains to be determined.

Initial evaluation of a novel, prototype, forward-viewing echoendoscope in a porcine arterial bleeding model (with video).

BACKGROUND: Real-time visualization of submucosal arterial flow at the base of an ulcer might improve endoscopic hemostasis by permitting more accurate assessment of the artery, precise targeting of therapy, and confirmation of vessel ablation. OBJECTIVE: To evaluate the utility of a novel, forward-viewing echoendoscope in identifying bleeding submucosal arteries, guiding hemostatic therapy, and confirming cessation of flow through treated vessels. DESIGN: In 7 pigs, a previously described porcine model for peptic ulcer hemorrhage was created by isolating the gastroepiploic and/or short gastric artery and tunneling it into the subserosal space at laparotomy. SETTING: Animal research facility. INTERVENTION: The prototype endoscope was used to image submucosal arterial flow. EUS guidance was then used to deliver endoscopic hemostatic therapy and assess treatment adequacy. MAIN OUTCOME MEASUREMENTS: Identification of the target submucosal artery and successful delivery of EUS-guided endoscopic therapy, evidenced by cessation of Doppler flow through the target vessel. RESULTS: Tunneled arteries were visualized endosonographically in all 7 cases. EUS-guided submucosal injection of epinephrine was successful in 2 of 2 cases. EUS-guided delivery of thermal hemostatic therapy was successful in 2 of 4 cases. Absence of flow through treated vessels was confirmed in cases in which EUS-guided therapy was successfully delivered. LIMITATIONS: Acute animal model. CONCLUSION: Proof of principle experiments in a porcine peptic ulcer hemorrhage model suggest that real-time sonographic imaging of submucosal arteries is feasible with a forward-viewing echoendoscope, and guided hemostatic therapy can be delivered.

Peritoneal inflammatory response of natural orifice translumenal endoscopic surgery (NOTES) versus laparoscopy with carbon dioxide and air pneumoperitoneum.

BACKGROUND: The immunologic and physiologic effects of natural orifice translumenal endoscopic surgery (NOTES) versus traditional surgical approaches are poorly understood. Previous investigations have shown that NOTES and laparoscopy share similar inflammatory cytokine profiles except for a possible late-phase tissue necrosis factor-alpha (TNF-alpha) depression with NOTES. The local peritoneal reaction and immunomodulatory influence of pneumoperitoneum agents in NOTES also are not known and may play an important role in altering the physiologic insult induced by NOTES. METHODS: In this study, 51 animals were divided into four study groups, which respectively underwent abdominal exploration via transgastric NOTES using room air (AIR) or carbon dioxide (CO(2)) or via laparoscopy (LX) using AIR or CO(2) for pneumoperitoneum. Laparotomy and sham surgeries were additionally performed as control conditions. Measurements of TNF-alpha, interleukin-1beta (IL-1beta), and IL-6 were performed for peritoneal fluid collected after 0, 2, 4, and 6 h and on postoperative days (PODs) 1, 2, and 7. RESULTS: Of the 45 animals assessed, 6 were excluded because of technical operative complications. The findings showed that LX-CO(2) generated the most pronounced response with all three inflammatory markers. However, no significant differences were detected between LX-CO(2) and either NOTES group at these peak points. No differences were encountered between NOTES-CO(2) and NOTES-AIR. Subgroup comparisons showed significantly higher levels of TNF-alpha and IL-6 with NOTES-CO(2) than with LX-AIR on POD 1 (p = 0.022) and POD 2 (p = 0.002). The LX-CO(2) subgroup had significantly higher levels of TNF-alpha than the LX-AIR subgroup at 4 h (p = 0.013) and on POD 1 (p = 0.021). No late-phase TNF-alpha depression occurred in the NOTES animals. CONCLUSION: The local inflammatory reaction to NOTES was similar to that with traditional laparoscopy, and the previously described late-phase systemic TNF-alpha depression in serum was not reproduced. At the peritoneal level, NOTES is no more physiologically stressful than laparoscopy. Furthermore, regardless of which gas was used, the role of the pneumoperitoneum agent did not affect the cytokine profile after NOTES, suggesting that air pneumoperitoneum is adequate for NOTES.

Endoscopic full-thickness resection of gastric lesions using a novel grasp-and-snare technique: evaluation in a porcine survival model.

BACKGROUND: Endoscopic full-thickness resection (EFTR) is a less-invasive method of en bloc removal of gastrointestinal tumors. In a previous nonsurvival animal experiment, the feasibility of a novel grasp-and-snare EFTR technique using a prototype tissue-lifting device was demonstrated. The objective of this study was to evaluate the safety and outcomes of this EFTR method in a porcine survival model. METHODS: EFTR of model stomach tumors was performed in seven pigs using a double-channel endoscope with a prototype tissue-lifting device through one channel and snare through the other. The lifting device was advanced through the snare loop and anchored to the gastric wall adjacent the model tumor. The lifting device was then partially retracted into the endoscope, causing the target tissue, including tumor, to evert into the gastric lumen. The open snare was then placed beyond the tumor around uninvolved gastric tissue. Resection was performed by delivering an electrosurgical current through the snare. EFTR defects were closed by using tissue anchors. After an intended 10-day observation period, the pigs were euthanized and necropsy was performed. RESULTS: All seven resections were successful with negative gross margins. No immediate complications occurred. Two defect closures failed during the early postoperative period, leading to infectious complications. The remaining intact closures were complicated by adjacent ulcers, one of which resulted in hemorrhage. CONCLUSIONS: Endoscopic full-thickness resection of gastric lesions using the grasp-and-snare technique is feasible in pigs. In this experiment, complications related to closure were significant. Further evaluation and modification of closure technique is necessary before studying this method of EFTR in humans.