Defining digital surgery: a SAGES white paper.

BACKGROUND: Digital surgery is a new paradigm within the surgical innovation space that is rapidly advancing and encompasses multiple areas. METHODS: This white paper from the SAGES Digital Surgery Working Group outlines the scope of digital surgery, defines key terms, and analyzes the challenges and opportunities surrounding this disruptive technology. RESULTS: In its simplest form, digital surgery inserts a computer interface between surgeon and patient. We divide the digital surgery space into the following elements: advanced visualization, enhanced instrumentation, data capture, data analytics with artificial intelligence/machine learning, connectivity via telepresence, and robotic surgical platforms. We will define each area, describe specific terminology, review current advances as well as discuss limitations and opportunities for future growth. CONCLUSION: Digital Surgery will continue to evolve and has great potential to bring value to all levels of the healthcare system. The surgical community has an essential role in understanding, developing, and guiding this emerging field.

Surgeon-performed endoscopic retrograde cholangiopancreatography. Outcomes of 2392 procedures at two tertiary care centers.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is a common procedure that, in the United States, is traditionally performed by gastroenterologists. We hypothesized that when performed by well-trained surgeons, ERCP can be performed safely and effectively. The objectives of the study were to assess the rate of successful cannulation of the duct of interest and to assess the 30-day complication and mortality rates. METHODS: We retrospectively reviewed the charts of 1858 patients who underwent 2392 ERCP procedures performed by five surgeons between August 2003 and June 2016 in two centers. Demographic and historical data, indications, procedure-related data and 30-day complication and mortality data were collected and analyzed. RESULTS: The mean age was 53.4 (range 7-102) years and 1046 (56.3%) were female. 1430 (59.8%) of ERCP procedures involved a surgical endoscopy fellow. The most common indication was suspected or established uncomplicated common bile duct stones (n = 1470, 61.5%), followed by management of an existing biliary or pancreatic stent (n = 370, 15.5%) and acute biliary pancreatitis (n = 173, 7.2%). A therapeutic intervention was performed in 1564 (65.4%), a standard sphincterotomy in 1244 (52.0%), stent placement in 705 (29.5%) and stone removal in 638 (26.7%). When cannulation was attempted, the rate of successful cannulation was 94.1%. When cannulation was attempted during the patient's first ERCP the cannulation rate was 92.4%. 94 complications occurred (5.4%); the most common complication was post-ERCP pancreatitis in 75 (4.2%), significant gastrointestinal bleeding in 7 (0.4%), ascending cholangitis in 11 (0.6%) and perforation in 1 (0.05%). 11 mortalities occurred (0.5%) but none of which were ERCP-related. CONCLUSION: When performed by well-trained surgical endoscopists, ERCP is associated with high success rate and acceptable complication rates consistent with previously published reports and in line with societal guidelines.

Gastroesophageal reflux after peroral endoscopic myotomy: a multicenter case-control study.

Background and study aims The variables associated with gastroesophageal reflux (GER) after peroral endoscopic myotomy (POEM) are largely unknown. This study aimed to: 1) identify the prevalence of reflux esophagitis and asymptomatic GER in patients who underwent POEM, and 2) evaluate patient and intraprocedural variables associated with post-POEM GER. Patients and methods All patients who underwent POEM and subsequent objective testing for GER (pH study with or without upper gastrointestinal [GI] endoscopy) at seven tertiary academic centers (one Asian, two US, four European) were included. Patients were divided into two groups: 1) DeMeester score ≥ 14.72 (cases) and 2) DeMeester score of < 14.72 (controls). Asymptomatic GER was defined as a patient with a DeMeester score ≥ 14.72 who was not consuming proton pump inhibitor (PPI). Results A total of 282 patients (female 48.2 %, Caucasian 84.8 %; mean body mass index 24.1 kg/m2) were included. Clinical success was achieved in 94.3 % of patients. GER evaluation was completed after a median follow-up of 12 months (interquartile range 10 - 24 months). A DeMeester score of ≥ 14.72 was seen in 57.8 % of patients. Multivariable analysis revealed female sex to be the only independent association (odds ratio 1.69, 95 % confidence interval 1.04 - 2.74) with post-POEM GER. No intraprocedural variables were associated with GER. Upper GI endoscopy was available in 233 patients, 54 (23.2 %) of whom were noted to have reflux esophagitis (majority Los Angeles Grade A or B). GER was asymptomatic in 60.1 %. Conclusion Post-POEM GER was seen in the majority of patients. No intraprocedural variables were identified to allow for potential alteration in procedural technique.

Laparoscopic redo fundoplication improves disease-specific and global quality of life following failed laparoscopic or open fundoplication.

INTRODUCTION: Laparoscopic fundoplication is associated with failure rates of up to 30% and redo operation rates of 5-8%. Redo fundoplication improves patient symptoms, but its impact on patient quality of life remains unclear. We hypothesized that laparoscopic redo fundoplication improves disease-specific and global quality of life in patients with recurrent symptoms following failed laparoscopic or open fundoplication. METHODS: Data for all patients undergoing a redo fundoplication between August 2009 and June 2014 were collected prospectively. Reflux symptoms and quality of life were assessed using the Gastroesophageal Reflux Symptom Scale (GERSS), the Gastroesophageal Reflux Disease Health-Related Quality of Life (GERD-HRQL), and the global quality of life Short Form-36 (SF-36) questionnaires obtained at 4 weeks and 16 months post-operatively. RESULTS: Forty-six patients underwent laparoscopic redo fundoplication during the study period for symptomatic hernia (n = 11), GERD (n = 18), or dysphagia (n = 17). GERSS improved from 41 at baseline to 9 at late follow-up (p < 0.001), and GERD-HRQL scores improved from 30 at baseline to 7 at late follow-up (p < 0.001). Median dysphagia scores decreased from 4.5 to 1 (p = 0.035). SF-36 scores demonstrated a significant improvement in general health (p = 0.016) and emotional well-being (p = 0.036) and a trend toward improved physical function (p = 0.068) in the post-operative period, but these improvements were not statistically significant at longer-term follow-up. Overall, 82% of patients reported satisfaction with their operation, and 96% reported that they would have the operation performed again given the benefit of hindsight. CONCLUSIONS: While associated with long operative times and significant complications, laparoscopic redo fundoplication produces a durable improvement in reflux symptoms and disease-specific quality of life. These procedures also improve global quality of life in the short term and are associated with high patient satisfaction.

Stray energy transfer during endoscopy.

INTRODUCTION: Endoscopy is the standard tool for the evaluation and treatment of gastrointestinal disorders. While the risk of complication is low, the use of energy devices can increase complications by 100-fold. The mechanism of increased injury and presence of stray energy is unknown. The purpose of the study was to determine if stray energy transfer occurs during endoscopy and if so, to define strategies to minimize the risk of energy complications. METHODS AND PROCEDURES: A gastroscope was introduced into the stomach of an anesthetized pig. A monopolar generator delivered energy for 5 s to a snare without contacting tissue or the endoscope itself. The endoscope tip orientation, energy device type, power level, energy mode, and generator type were varied to mimic in vivo use. The primary outcome (stray current) was quantified as the change in tissue temperature (°C) from baseline at the tissue closest to the tip of the endoscope. Data were reported as mean ± standard deviation. RESULTS: Using the 60 W coag mode while changing the orientation of the endoscope tip, tissue temperature increased by 12.1 ± 3.5 °C nearest the camera lens (p < 0.001 vs. all others), 2.1 ± 0.8 °C nearest the light lens, and 1.7 ± 0.4 °C nearest the working channel. Measuring temperature at the camera lens, reducing power to 30 W (9.5 ± 0.8 °C) and 15 W (8.0 ± 0.8 °C) decreased stray energy transfer (p = 0.04 and p = 0.002, respectively) as did utilizing the low-voltage cut mode (6.6 ± 0.5 °C, p < 0.001). An impedance-monitoring generator significantly decreased the energy transfer compared to a standard generator (1.5 ± 3.5 °C vs. 9.5 ± 0.8 °C, p < 0.001). CONCLUSION: Stray energy is transferred within the endoscope during the activation of common energy devices. This could result in post-polypectomy syndrome, bleeding, or perforation outside of the endoscopist's view. Decreasing the power, utilizing low-voltage modes and/or an impedance-monitoring generator can decrease the risk of complication.

Incidence of abdominal wall metastases following percutaneous endoscopic gastrostomy placement in patients with head and neck cancer.

INTRODUCTION: Percutaneous endoscopic gastrostomy (PEG) tubes are an effective modality for enteral nutrition in patients with head and neck cancer; however, there have been documented case reports of "seeding" of the abdominal wall by the theoretic risk of dragging the tube along the tumor during PEG placement. The objective of this study is to determine the incidence and contributing risk factors leading to metastasis to the abdominal wall following PEG placement in patients with head and neck cancer. METHODS: A retrospective chart review was performed on patients diagnosed with head and neck malignancy who underwent PEG placement between 1/5/2009 and 12/22/2014. Variables collected included development of abdominal wall metastases, type of malignancy and tumor characteristics, smoking history, PEG placement technique, and survival following recurrence. Data were then analyzed for overall trends. RESULTS: Out of 777 patients analyzed, a total of five patients with head and neck malignancy were identified with abdominal wall metastasis following PEG tube placement with an overall incidence of 0.64% over an average follow-up of 27.55 months. All of these patients underwent PEG tube insertion via a Pull technique. One patient was found to have a clinically evident and symptomatic stomal metastasis, while the other four patients had radiologically detected metastases either on CT or PET scan. All of the identified patients were found to have stage IV oral cancer at time of initial diagnosis of their head and neck malignancy, followed by widespread distant metastatic disease at time of presentation with their PEG site stomal metastasis. CONCLUSION: Abdominal wall metastases following PEG placement are a rare but serious complication in patients with head and neck malignancy.

Gastroesophageal reflux symptoms do not correlate with objective pH testing after peroral endoscopic myotomy.

INTRODUCTION: Peroral endoscopic myotomy (POEM) is an emerging treatment for esophageal achalasia. Postoperative reflux has been found in a significant number of patients, but it is unknown whether subjective reports of reflux correlate with objective pH testing. The purpose of this study was to compare the objective rate of reflux with standardized reflux symptom scales after POEM. Our hypothesis was that subjective symptoms would not correlate with objective measurement of reflux. METHODS AND PROCEDURES: Data on all patients undergoing POEM were collected prospectively between August 2012 and June 2014 and included demographics, objective testing (48-h pH probe, manometry, endoscopy), as well as gastroesophageal reflux disease health-related quality of life (GERD-HRQL), GERD symptom scale (GERSS), and antacid use. RESULTS: Forty-three patients underwent POEM during the study period. The mean age was 53.5 ± 17.4 years with a BMI of 29.6 ± 8.4 kg/m(2), and 27 (63%) were male. Forty-two patients (98%) completed at least 6 months of follow-up, and 26 (60%) underwent repeat pH measurement. Dysphagia scores improved from 4 (0-5) at baseline to 0 (0-3) (p < 0.001). On follow-up pH testing, 11 (42%) were normal and 15 (58%) had elevated DeMeester scores. Postoperative GERSS or GERD-HRQL scores did not correlate with DeMeester scores on Spearman's rank-order tests (r = 0.02, p = 0.93 and r = 0.04, p = 0.50, respectively). Postoperative PPI use was not significantly associated with normal or abnormal pH testing: 5 of 7 (71%) patients who were taking PPIs postoperatively had abnormal DeMeester scores compared to 9 of 18 (50%) of patients who were not taking PPIs (p = 0.332). CONCLUSIONS: Peroral endoscopic myotomy provides excellent dysphagia relief for patients with achalasia, but is associated with a high rate of reflux on pH testing postoperatively. Subjective symptoms are not a reliable indicator of postoperative reflux. Routine pH testing should be considered in all patients following POEM.

Prior treatment does not influence the performance or early outcome of per-oral endoscopic myotomy for achalasia.

INTRODUCTION: Per-oral endoscopic myotomy (POEM) is an emerging treatment for achalasia. Pneumatic dilation, botulinum toxin injection, and previous myotomy increase the difficulty of subsequent Heller myotomy, but their impact on POEM remains unknown. The purpose of this study was to compare patients who had undergone prior treatment for their achalasia to those undergoing POEM as an initial therapy. METHODS AND PROCEDURES: All patients undergoing POEM were entered into a prospective database from August 2012 to October 2014. Data collected included demographics, dysphagia and symptom survey scores, operative time, clips required for mucosotomy closure, perioperative complications and length of hospital stay. RESULTS: Forty-five patients underwent POEM during the study period. Fifteen (30%) had undergone previous treatment (seven Botox injection, five pneumatic dilation and three Heller myotomy). Primary POEM patients were younger than those who had had prior treatment (mean age 46 ± 17 vs. 64 ± 12 years, p < 0.001), but gender, body mass index and ASA class were not significantly different. There were no conversions to Heller myotomy or perioperative complications in either group. Operative time for primary POEM was 103 ± 27 versus 102 ± 29 min following prior treatment (p = 0.84). Mucosotomy closure required a median 7 (4-16) and 8 (5-16) clips, respectively (p = 0.08). Length of stay was 1 day in each group. Median dysphagia scores decreased from 4 (0-5) to 1 (0-4) following primary POEM and 4 (0-5) to 0 (0-4) in the prior treatment group (p = 0.45) during a median follow-up of 10 months (5-17 months). All patients in each group expressed satisfaction with their procedure and would undergo the procedure again given the benefit of hindsight. CONCLUSION: Per-oral endoscopic myotomy is a safe and effective treatment for achalasia which improves dysphagia and disease-specific quality of life. Previous endoscopic or laparoscopic treatment of achalasia does not affect the performance or early outcome of POEM.

Quality-of-life scores in laparoscopic preperitoneal inguinal hernia repair.

BACKGROUND: Published support exists for using lightweight polypropylene mesh (PPM) to repair inguinal hernias with increased biocompatibility and decreased foreign body reaction and pain. However, quality of life (QOL) has not been assessed. We assess QOL in patients undergoing laparoscopic totally extraperitoneal hernia repair (TEP) with lightweight PPM. METHODS: We performed an IRB-approved study of patients undergoing TEP hernia repair. Demographic information and hernia characteristics were collected perioperatively. Baseline Short Form-36 (SF-36), Carolinas Comfort Scale (CCS), and visual analog scale (VAS) for pain were performed preoperatively, and then after 1, 26, and 52 weeks. RESULTS: Forty-eight patients undergoing TEP with mesh were selected. Average age was 43.2 years (SD = 13.2), and average BMI was 26.1 kg/m(2) (SD = 4.3). Procedures include bilateral hernia, right inguinal hernia, and left inguinal hernia repairs. Mean scores on the CCS(®) and VAS were low during the immediate post-op period and 1 year. SF-36 mean scores for body pain, physical function, and role physical showed decreases at the postoperative survey and then subsequent increases. Pain-associated scores increased during the immediate post-op period. CCS and SF-36 scores demonstrated improvement after 1 year. There was no significant difference in VAS. Bilateral repair patients reported more pain and reduced physical function versus unilateral repairs. Patients with larger mesh reported greater pain scores and reduced physical function scores. CONCLUSIONS: Laparoscopic inguinal hernia repair is associated with initial declines in QOL in the postoperative period. Improvements appear in the long term. General health does not appear to be impacted by laparoscopic TEP. Smaller mesh and unilateral repairs are associated with improved QOL following laparoscopic TEP with PPM. Multiple metrics for QOL are required to reflect patient recovery.

Endoscopic mucosal resection for staging and treatment of early esophageal carcinoma: a single institution experience.

BACKGROUND: Endoscopic mucosal resection (EMR) has emerged for evaluation and treatment of esophageal nodules. We report our initial experience with EMR for T staging and management of early esophageal cancer. METHODS: We reviewed patients undergoing EMR for esophageal adenocarcinoma between 2008 and 2013. The primary outcome measure was needed for esophagectomy. Secondary outcomes included complete eradication of adenocarcinoma, recurrence or persistence of cancer, nodal status for those undergoing esophagectomy, and complications of endoscopic treatment. RESULTS: During the study period, 24 patients underwent EMR demonstrating carcinoma, and a grossly margin negative endoscopic resection was achieved in all cases. Ten patients (42 %) had evidence of submucosal invasion and were referred for esophagectomy. Patients with margin negative EMR (n = 10, 42 %) or positive radial margins (n = 4, 16 %) underwent endoscopic surveillance and treatment with radiofrequency ablation or repeat EMR as needed. Thirteen patients (93 %) with intramucosal cancer (IMC) have been successfully managed with ongoing endoscopic surveillance and treatment with a median follow-up of 15.5 months. One patient underwent esophagectomy due to recurrent IMC in the setting of long-segment multifocal high-grade dysplasia. There were no esophageal perforations, one patient developed a self-limited gastrointestinal hemorrhage following EMR, and one had an esophageal stricture following endoscopic management. CONCLUSIONS: IMC can be successfully managed endoscopically and thus esophagectomy is avoided in a significant proportion of patients. Endoscopic management may be utilized in the setting of complete resection or radial margin involvement without evidence of submucosal invasion. Close endoscopic follow-up is of paramount importance even in those with negative margins, because recurrent disease may occur following EMR in these patients.

Near-infrared fluorescent cholangiography facilitates identification of biliary anatomy during laparoscopic cholecystectomy.

BACKGROUND: Intraoperative cholangiography (IOC) is the current gold standard for biliary imaging during laparoscopic cholecystectomy (LC). However, utilization of IOC remains low. Near-infrared fluorescence cholangiography (NIRF-C) is a novel, noninvasive method for real-time, intraoperative biliary mapping. Our aims were to assess the safety and efficacy of NIRF-C for identification of biliary anatomy during LC. METHODS: Patients were administered indocyanine green (ICG) prior to surgery. NIRF-C was used to identify extrahepatic biliary structures before and after partial and complete dissection of Calot's triangle. Routine IOC was performed in each case. Identification of biliary structures using NIRF-C and IOC, and time required to complete each procedure were collected. RESULTS: Eighty-two patients underwent elective LC with NIRF-C and IOC. Mean age and body mass index (BMI) were 42.6 ± 13.7 years and 31.5 ± 8.2 kg/m(2), respectively. ICG was administered 73.8 ± 26.4 min prior to incision. NIRF-C was significantly faster than IOC (1.9 ± 1.7 vs. 11.8 ± 5.3 min, p < 0.001). IOC was unobtainable in 20 (24.4 %) patients while NIRF-C did not visualize biliary structures in 4 (4.9 %) patients. After complete dissection, the rates of visualization of the cystic duct, common bile duct, and common hepatic duct using NIRF-C were 95.1, 76.8, and 69.5 %, respectively, compared to 72.0, 75.6, and 74.3 % for IOC. In 20 patients where IOC could not be obtained, NIRF-C successfully identified biliary structures in 80 % of the cases. Higher BMI was not a deterrent to visualization of anatomy with NIRF-C. No adverse events were observed with NIRF-C. CONCLUSIONS: NIRF-C is a safe and effective alternative to IOC for imaging extrahepatic biliary structures during LC. This technique should be evaluated further under a variety of acute and chronic gallbladder inflammatory conditions to determine its usefulness in biliary ductal identification.

Laparoscopic Inguinal Hernia Repair With a Novel Hernia Mesh Incorporating a Nitinol Alloy Frame Compared With a Standard Lightweight Polypropylene Mesh.

BACKGROUND: Numerous mesh materials are available for laparoscopic inguinal hernia repair. The role of fixation of mesh in laparoscopic inguinal hernia repair remains controversial. Mesh materials have been engineered to anatomically conform to the pelvis to potentially reduce or eliminate the need for fixation. This study evaluates the outcomes of laparoscopic inguinal hernia utilizing a device consisting of a lightweight polypropylene mesh with a nitinol frame (Rebound HRD) compared with repair with lightweight polypropylene mesh with permanent tack fixation. METHODS: A prospective randomized trial evaluating the outcomes of laparoscopic inguinal hernia repair with a lightweight polypropylene mesh with a nitinol frame (N-LWM) compared with standard lightweight polypropylene mesh (LWM) was conducted. Randomization was performed at an N-LWM to LWM ratio of 2:1. Repairs were standardized to a laparoscopic extraperitoneal approach without fixation for N-LWM and titanium tack fixation for LWM repairs. Follow-up assessments were performed at 7 days, 6 months, and 1 year. Outcome measures include visual analog pain scale (VAS), Short Form 36 (SF-36), Carolinas Comfort Scale (CCS), operative details, complications, and recurrences. RESULTS: There were 47 patients that underwent laparoscopic inguinal hernia repair and adhered to study protocol (31 N-LWM, 16 LWM). The groups did not differ significantly in age, body mass index, ethnicity, or employment. The N-LWM group had bilateral mesh placed in 51.6% and LWM 43.8% (P = .76). Operative duration was similar, 59.6 ± 23.1 minutes for LWM and 62.4 ± 26.7 minutes for N-LWM (P = .705) as was mesh handling time was 5.4 ± 3.1 minutes LWM versus 7.3 ± 3.9 minutes N-LWM (P = .053). VAS, CCS, and SF-36 survey results were similar between groups. There was one recurrence (0.03%) in the N-LWM group. CONCLUSIONS: Nitinol-framed lightweight polypropylene mesh may be safely used during laparoscopic inguinal hernia repair with outcomes comparable to LWM at 1 year. N-LWM does not impact operating room time, mesh handling time, pain, recurrences, or complications.

Endoscopic management of high-grade dysplasia and intramucosal carcinoma: experience in a large academic medical center.

BACKGROUND: Esophagectomy has been the standard treatment for Barrett's esophagus (BE) with high-grade dysplasia (HGD) and intramucosal cancer (IMC). Recently, endoscopic mucosal resection (EMR) and radiofrequency ablation (RFA) have become the preferred treatment for these patients in some centers. We report a single institution series of patients undergoing endoscopic management of HGD and IMC. METHODS: Nineteen patients underwent endoscopic treatment for HGD or IMC between 2009 and 2012. The primary outcome measure was progression of BE necessitating esophagectomy. Secondary outcomes included complete eradication of intestinal metaplasia (CE-IM), complete eradication of dysplasia (CE-D), recurrence or progression of BE or dysplasia, and complications. Patients were followed for a median follow-up interval of 19 months following completion of RFA treatment. RESULTS: Three patients (16 %) had a presenting diagnosis of IMC, and 16 (84 %) were treated for HGD. Twelve (63 %) had long-segment BE; the median length of BE was 5 cm. Ten (53 %) patients underwent EMR prior to RFA. CE-D was achieved in 88 % of patients, and CE-IM was achieved in 65 % of patients. A median of 2 (1-7) treatments were required, and there were no immediate post-procedure complications. Two patients developed recurrent dysplasia following complete eradication of BE, and each case was successfully managed with repeat RFA. Three patients (16 %) required esophagectomy within 6 months following RFA. A complete surgical resection was achieved in each case, and none of the patients developed lymph node metastases. CONCLUSIONS: Complete eradication of HGD and IMC can be achieved via endoscopic therapy, thus avoiding esophagectomy in the majority of patients. However, a subset of patients will fail this treatment approach and will require surgical resection. With aggressive endoscopic treatment and surveillance, these patients can be identified at an early stage while curative resection is still possible.

Fundamentals of Endoscopic Surgery cognitive examination: development and validity evidence.

BACKGROUND: Flexible endoscopy is an integral part of surgical care. Exposure to endoscopic procedures varies greatly in surgical training. The Society of American Gastrointestinal and Endoscopic Surgeons has developed the Fundamentals of Endoscopic Surgery (FES), which serves to teach and assess the fundamental knowledge and skills required to practice flexible endoscopy of the gastrointestinal tract. This report describes the validity evidence in the development of the FES cognitive examination. METHODS: Core areas in the practice of gastrointestinal endoscopy were identified through facilitated expert focus groups to establish validity evidence for the test content. Test items then were developed based on the content areas. Prospective enrollment of participants at various levels of training and experience was used for beta testing. Two FES cognitive test versions then were developed based on beta testing data. The Angoff and contrasting group methods were used to determine the passing score. Validity evidence was established through correlation of experience level with examination score. RESULTS: A total of 220 test items were developed in accordance with the defined test blueprint and formulated into two versions of 120 questions each. The versions were administered randomly to 363 participants. The correlation between test scores and training level was high (r = 0.69), with similar results noted for contrasting groups based on endoscopic rotation and endoscopic procedural experience. Items then were selected for two test forms of 75 items each, and a passing score was established. CONCLUSIONS: The FES cognitive examination is the first test with validity evidence to assess the basic knowledge needed to perform flexible endoscopy. Combined with the hands-on skills examination, this assessment tool is a key component for FES certification.

Specialized instrumentation facilitates stable peritoneal access, gastric decompression, and visualization during transgastric endoscopic peritoneoscopy.

PURPOSE: The lack of high-fidelity instrumentation has impeded the development and implementation of natural orifice transluminal endoscopic surgery (NOTES). A steerable flexible trocar (SFT), a rotary access needle (RAN), and an articulating needle knife were developed as components of a flexible instrument set to facilitate transgastric peritoneal access and transluminal abdominal procedures. This cohort study aimed to assess the safety, feasibility, and efficacy of these devices during transgastric peritoneoscopy. METHODS: Ten morbidly obese patients undergoing laparoscopic Roux-en-Y gastric bypass participated in the study. Following laparoscopic access, transgastric peritoneal access was established using the SFT and RAN, and transgastric peritoneoscopy performed. NOTES adhesiolysis was performed in 2 patients with significant intra-abdominal adhesions due to prior surgery. Outcome measures included time to enter the peritoneal cavity, ability to visualize each quadrant of the abdomen, ability to perform adhesiolysis, and complications. RESULTS: Ten patients with a median body mass index as stated in table 1 of 47.5 kg/m(2) were enrolled. Successful transgastric access was achieved in 8 of the 10 patients. One procedure was aborted because of difficulty creating the gastrotomy. Another procedure was aborted because of the difficult passage of the device through the oropharynx. An upper esophageal laceration occurred in one patient. Transgastric peritoneal access required 17.4 ± 5.5 minutes, and peritoneoscopy averaged 24.7 ± 7.6 minutes. The 4 abdominal quadrants were visualized and were accessible with the endoscope in all patients. CONCLUSIONS: The SFT and RAN facilitate transgastric peritoneal access and visualization of difficult-to-reach areas of the peritoneum. These devices provide advanced instrumentation for transgastric NOTES procedures; however, care must be taken during the transoral insertion to avoid complications.

Placement technique impacts gastrostomy tube-related complications amongst head and neck cancer patients.

OBJECTIVES: Percutaneous endoscopic gastrostomy (PEG) placement is essential for the provision of enteral nutrition in select head and neck cancer (HNC) patients. Minimally invasive tube placement is facilitated through one of two techniques, push or pull, but there have been conflicting results regarding safety profiles of these procedures. The objectives of this study were to determine the association of PEG insertion technique with gastrostomy tube complications, including stomal metastases. METHODS: A multi-institutional retrospective cohort study of patients with HNC undergoing PEG insertion by either the pull (gastroscope assisted) or push (fluoroscopy assisted) technique was performed. Tube-related complications included infection, dislodgement, deterioration, leak, and other. Adjusted analysis was performed via a multivariable logistic regression model. RESULTS: 1,575 patients were included across three institutions. Tube-related complications occurred in 36% of patients, the most common being peristomal leak (13%) and infection (16%). The push technique (OR 2.66, 95% CI: 1.42-4.97), and the presence of T4 disease (OR 4.62, 95% CI: 1.58-13.51), were associated with a greater risk of developing any tube-related complication. Infection rates were similar between pull and push cohorts. All detected stoma metastases occurred with the pull technique, with an overall prevalence of 0.32% amongst the cohort. CONCLUSIONS: The push technique is associated with a greater risk of developing any tube-related complication, but the rate of stomal metastases may be higher with the pull technique. There is potential for quality improvement measures to improve tube-related complications associated with either technique.

Epiregulin as an Alternative Ligand for Leptin Receptor Alleviates Glucose Intolerance without Change in Obesity.

The leptin receptor (LepR) acts as a signaling nexus for the regulation of glucose uptake and obesity, among other metabolic responses. The functional role of LepR under leptin-deficient conditions remains unclear. This study reports that epiregulin (EREG) governed glucose uptake in vitro and in vivo in Lepob mice by activating LepR under leptin-deficient conditions. Single and long-term treatment with EREG effectively rescued glucose intolerance in comparative insulin and EREG tolerance tests in Lepob mice. The immunoprecipitation study revealed binding between EREG and LepR in adipose tissue of Lepob mice. EREG/LepR regulated glucose uptake without changes in obesity in Lepob mice via mechanisms, including ERK activation and translocation of GLUT4 to the cell surface. EREG-dependent glucose uptake was abolished in Leprdb mice which supports a key role of LepR in this process. In contrast, inhibition of the canonical epidermal growth factor receptor (EGFR) pathway implicated in other EREG responses, increased glucose uptake. Our data provide a basis for understanding glycemic responses of EREG that are dependent on LepR unlike functions mediated by EGFR, including leptin secretion, thermogenesis, pain, growth, and other responses. The computational analysis identified a conserved amino acid sequence, supporting an evolutionary role of EREG as an alternative LepR ligand.

A review of 130 humans enrolled in transgastric NOTES protocols at a single institution.

BACKGROUND: The methodology of Natural Orifice Translumenal Endoscopic Surgery (NOTES) has been validated in both human and animal models. Herein is a discussion of our experience gained from the initial 130 patients enrolled in transgastric pre-NOTES and NOTES protocols at our institution. METHODS: A retrospective review of our research database was performed for all patients enrolled in NOTES protocols. The infectious risk of a gastrotomy with and without a NOTES procedure was assessed in 100 patients. Eighty patients completed a true NOTES protocol looking at staging, access, and insufflation with select patients evaluating the potential for bacterial contamination of the abdominal compartment. RESULTS: A total of 130 patients have completed pre-NOTES and NOTES protocols at our institution. We observed no clinically significant contamination of the abdomen secondary to transgastric procedures in 100 patients. Diagnostic transgastric endoscopic peritoneoscopy (DTEP) was completed in 20 patients with pancreatic head masses and found to have a 95% concordance with laparoscopic exploration for assessment of peritoneal metastases. Blind endoscopic gastrotomy and DTEP were evaluated in 40 patients who underwent laparoscopic Roux-en-Y gastric bypass procedures (LSRYGB) and were found to be safe, reliable, and without a clinically significant risk of contamination. Endoscopic peritoneal insufflation was successfully established and correlated with standard laparoscopic insufflation in 20 patients. CONCLUSIONS: Transgastric NOTES is a safe alternative approach to accessing the peritoneal cavity in humans. The risk of bacterial contamination secondary to peroral and transgastric access is clinically insignificant. A device for the facile closure of the gastric defect is the sole factor limiting institution of this methodology as a standalone technique.

A comparison of outcomes between open and laparoscopic surgical repair of recurrent inguinal hernias.

BACKGROUND: Inguinal hernia recurrence after surgical repair is a major concern. The authors report their experience with open and laparoscopic repair of recurrent inguinal hernias. METHODS: After institutional review board approval, a retrospective review was performed with the charts of 197 patients who had undergone surgical repair of recurrent inguinal hernias from January 2000 through August 2009, and the data for 172 patients who met the inclusion criteria were analyzed. Surgical variables and clinical outcomes were compared using Student's t test, the Mann-Whitney U test, chi-square, and Fisher's exact test as appropriate. RESULTS: The review showed that 172 patients had undergone either open mesh repair (n=61) or laparoscopic mesh repair (n=111) for recurrent inguinal hernias. Postoperative complications were experienced by 8 patients in the open group and 17 patients in laparoscopic group (p=0.70). Five patients (8.2%) in the open group and four patients (3.6%) in the laparoscopic group had re-recurrent inguinal hernias (p=0.28). Four patients in the open group (9.5%) and no patients in the laparoscopic group had recurrence during long-term follow-up evaluation (p=0.046). In the laparoscopic group, 76 patients (68.5%) underwent total extraperitoneal (TEP) repair, and 35 patients (31.5%) had transabdominal preperitoneal (TAPP) repair. Postoperative complications were experienced by 13 patients in the TEP group and 4 patients in the TAPP group (p=0.44). Two patients (2.6%) in the TEP group and two patients (5.7%) in the TAPP group had re-recurrent inguinal hernias (p=0.59). CONCLUSIONS: This retrospective review showed no statistical difference in the re-recurrence rate between the two techniques during short-term follow-up evaluation. However, the laparoscopic technique had a significantly lower re-recurrence rate than the open technique during long-term follow-up evaluation. Both procedures were comparable in terms of intra- and postoperative complications. Among laparoscopic techniques, TEP and TAPP repair are acceptable methods for the repair of recurrent inguinal hernia. A multicenter prospective randomized control trial is needed to confirm the findings of this study.

Transgastric endoscopic peritoneoscopy does not lead to increased risk of infectious complications.

BACKGROUND: It remains important to determine the risk of bacterial contamination and infectious complications of the peritoneal cavity as it pertains to transgastric natural orifice translumenal endoscopic surgery (NOTES) procedures. The infectious implications of such procedures have been quantified in animal models. This report discusses the infectious risks of transgastric endoscopic peritoneoscopy (TEP) in a human clinical trial. METHODS: Under institutional review board approval, 40 patients scheduled for laparoscopic Roux-en-Y gastric bypass (LRYGB) participated in this study. The TEP procedure was performed without preoperative gastric decontamination and without laparoscopic guidance. Preoperative intravenous antibiotics were given. Saline aspirates were taken from the gastric lumen before endoscopic gastrotomy creation and from the peritoneal cavity after transgastric access. Samples were sent for culture, identification, and bacterial counts. Subgroup analysis was performed on patients taking proton pump inhibitors (PPIs). These data were compared with data for "sterile" peritoneal aspirates from a historical cohort of 50 patients undergoing LRYGB. RESULTS: The median number of bacteria isolated from the gastric aspirates was 980 colony-forming units (CFU)/ml (n=40). The median number of bacteria isolated from the peritoneal aspirates was 323 CFU/ml. Cross-contamination from the stomach to the peritoneal cavity was documented in eight cases. No abscesses or anastomotic leaks were recorded. One port-site infection occurred. Subgroup analysis of 15 patients receiving PPIs showed elevated bacterial counts in gastric aspirates and the post-TEP peritoneal samples compared with patients not receiving PPIs (n=25). This subgroup on PPI's did not have an increase in infectious complications. CONCLUSIONS: Contamination of the peritoneal cavity does occur with TEP, but this does not lead to an increased risk of infectious complications. Similarly, patients receiving PPIs have an increased gastric bacterial load and increased contamination after TEP but not an increased risk of infectious complications.