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The Independent Newspaper for the General Surgeon

INTERNATIONAL EDITION

Volume 2 • 2013 GENERALSURGERYNEWS.COM ®

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Single-Port Liver Resection Feasible in Selected Patients

Ultrasound as Gold Standard for Hernia Diagnosis? Group Finds It Better Than CT; But Will It Be Widely Adopted?

Endoscopic Approach Good Option for Early Breast Cancer Negative Margins, Better Cosmesis; Main Drawback Is Longer Procedure Time

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urgeons from Vanderbilt University are recommending that dynamic abdominal sonography for hernia (DASH) replace computed tomography (CT) as the gold standard for the radiographic identification and characterization of incisional hernia. “The DASH examination is an accurate alternative to the CT scan for diagnosing abdominal wall hernias, with additional benefits of no radiation exposure and instant bedside interpretation,” concluded Benjamin K. Poulose, MD, MPH, assistant professor of general surgery, Vanderbilt University Medical Center, Nashville, Tenn., and his colleagues in a report published in the March edition of the Journal of the American College of Surgeons (216:447-453). Dr. Poulose, co-author William B. Beck and their colleagues studied 181 patients who underwent surgeon-performed DASH, as well as CT scans of the abdomen and pelvis. Surgeons and radiologists

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procedures on post-meal glucose reactions. Mitchell S. Roslin, MD, FACS, Lenox Hill Hospital, New York City, and his colleagues first became interested in glucose tolerance testing after noticing that many of their

new single-port pretumoral approach has shown promise in treating early breast cancer, according to a new study presented at the 21st International Congress of the European Association for Endoscopic Surgery (EAES). This pretumoral transaxillary retromammary (TARM) approach pproach to video-assisted ted breast surgery (VABS) (VAB performed on 20 pat atients was safe and eff ffective. The approoach also came wiith excellent cossmetic outcomees, preserving the he original shape of the breast, said lead author uthor Koji Y Yamashita, MD, PhD, Department of Breast Surgery, Nippon Medical School, Tokyo. He presented the results at the EAES meeting in Vienna, in June. Currently in the United States, the standard of care for breast-conserving surgery includes lumpectomy, partial mastectomy and quadrantectomy, but these methods require a long incision

see GASTRIC BYPASS page 12

see BREAST SURGERY page 16

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urgeons have been performing laparoscopic liver resections since the late 1980s, but the standard approach to managing liver malignancies is still open surgery. “Liver resection has been one of the last areas where we’ve applied

minimally invasive techniques,” said T. Peter Kingham, MD, Department of Surgery, Hepatopancreatobiliary Service, Memorial Sloan-Kettering Cancer Center, New York City. “It’s a challenge to safely perform the same see LIVER RESECTION page 16

Study Suggests Gastric Bypass Causes Glucose Spikes, Crashes B Y M ONICA S MITH

see ULTRASOUND page 9

D

REPORT Clinical Performance and Economic Analysis of GORE® BIO-A® Tissue Reinforcement See insert at page 12

espite its reputation as the gold standard for weight loss, gastric bypass surgery may result in a post-meal glucose spike followed by a blood sugar crash that causes between-meal hunger, according to a new study. The research examined the effects of different bariatric

INSIDE In the News

Clinical Review

Surgeons’ Lounge

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More Overlap Means Fewer Hernia Recurrences, Says Surgeon With More Than 1,200 Casees

Postoperative Pain Management in Anorectal Surgery

Coverage of the International Colorectal Disease Symposium and the Surgery of the Foregut Symposium


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In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Single-Port Surgery for Early Gastric Cancer Appears Safe, Feasible

Dear Reader, Welcome to the 2013 International Edition of General Surgery News. In this issue, we are pleased to highlight research from the recent annual meeting of the European Association for Endoscopic Surgery, in Vienna, along with updates on research and technology from surgeon investigators around the world. Along with these news reports, we feature another installment of The Surgeons’ Lounge. In this column, the editors include highlights from recent symposia—The International Colorectal Disease Symposium and the Surgery of the Foregut Symposium—directed by Steven Wexner, MD and Raul Rosenthal, MD, from Cleveland Clinic Florida, Weston. And, on page 13 you will find a surgeon-authored clinical review of pain management in anorectal surgery. We hope that you find this issue of value to your practice. After perusing this edition, we ask that you take a moment to fill out the enclosed survey so that we may better serve you in the future. Thank you for your readership, and we look forward to hearing from you.

Better Cosmesis; Long Way To Being Standard; Success May Depend on Technology B Y V ICTORIA S TERN

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Sincerely, Kevin Horty, Group Publication Editor khorty@mcmahonmed.com Maureen Sullivan, Associate Editor msullivan@mcmahonmed.com

educed-port laparoscopic distal gastrectomy to treat early gastric cancer is a safe and feasible procedure that provides improved cosmesis and fewer port-related complications, according to a study presented at the recent International Congress of the European Association for Endoscopic Surgery (EAES) in Vienna. The current standard of care for gastric cancer is open surgery, which includes subtotal gastrectomy or total gastrectomy with D2 lymph node dissection. “Laparoscopic gastrectomy is still classified as an investigational treatment because there is no level 1 evidence of long-term oncologic outcome even in early gastric cancer,” said Hyung-Ho Kim, MD, PhD, chairman of the Department of Surgery, Seoul National University Bundang Hospital, in Korea, and president of the Korean

Laparoscopic Gastrointestinal Surgery Study Group, who was not involved in the current research. In the United States, most gastric cancers are clinically advanced when diagnosed, but in Asian countries, many of these cancers are detected early. This means minimally invasive approaches could benefit patients in countries with robust early detection methods, said lead author Hiroyuki Kashiwagi, MD, Department of Surgery, Shonai Amarume Hospital, Yamagata, Japan. Recently, laparoscopic approaches to treating early gastric cancer have started to gain momentum in East Asia, especially in Korea and Japan, with reports showing better early postoperative outcomes compared with open surgery. But only a handful of reports exist due to the technical difficulty and lack of tools see GASTRIC CANCER page 4

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INFECTIOUS DISEASE SPECIAL EDITION

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In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Group Presents Experience With Duodenal Bypass Liner for Weight Loss Glycemic Control, Not Diabetes Status, Seen as Key Predictor of Success B Y M ONICA S MITH BALTIMORE—In obese patients who receive a duodenal-jejunal bypass liner (DJBL), glycemic control may be a more significant predictor of successful weight loss than the presence or absence of type 2 diabetes, according to recently presented research. A DJBL is a highly flexible, nutrientimpermeable, 60-cm sleeve placed endoscopically that covers the entire duodenum and the first portion of the jejunum. “After one year of treatment, patients with a DJBL lose an average of 47% of their excess weight. However, as with bariatric surgery, weight loss is variable with this device,” said Rodrigo Munoz, MD, PhD, Departamento de Cirugia Digestiva, Escuela de Medicina, Pontificia, Universidad Catolica de Chile, in Santiago, Chile. “The aim of this study was to identify clinical predictors of weight loss in this group of patients treated with this device for one year.” The study was presented at the 2013 annual meeting of the Society of American Gastrointestinal and Endoscopic Surgeons.

Seeking a correlation between baseline variables and weight loss, Dr. Munoz and his colleagues collected data every month for one year on 61 patients treated with a DJBL. The collected variables included demographic information, baseline comorbidities, and anthropometric and biochemical characteristics. The majority of the patients were women, with an average age of 35 years and average body mass index of 43 kg/m2. Twenty-one of the patients (34%) had type 2 diabetes. At one year, the average percentage of excess body weight loss was 47%, with some patients at either extreme, having lost little of their excess weight or almost all of it. Coincidentally, nine patients (14.7%) lost more than the average, and nine lost less than the average. “Our univariate analysis indicated three variables inversely associated with weight loss at one year: insulin resistance determined by HOMA [homeostatic model assessment], fasting glycemia and Hb [hemoglobin]A1c,” Dr. Munoz said. “But after we controlled for all these three variables, only HbA1cc was inversely and independently associated with the weight loss effect of this device.” In contrast with previous studies, the presence of type 2 diabetes did not affect the weight loss effect of the DJBL. Dr. Munoz concluded that

GASTRIC CANCER jcontinued from page 3

designed specifically for such procedures. For instance, three studies detailing surgeons’ initial clinical experiences with single-incision laparoscopic distal gastrectomy for early gastric cancers have all required the use of one or two assistant ports (Surg Endoscc 2011;25:2400-2404; Surg Laparosc Endosc Percutan Techh 2012;22:e214-e216; Surg Endoscc 2012;26:1490-1494). Now, the availability of multichannel ports, such as the single-incision laparoscopic surgery (SILS) port (Covidien, Japan), has made reduced-port laparoscopic distal gastrectomy more technically viable, allowing surgeons to insert up to three instruments through one port. In the current study, Dr. Kashiwagi and his colleagues from the Department of Surgery, Shonai Amarume Hospital, Yamagata, Japan, performed a laparoscopic distal gastrectomy on 10 patients (six men, four women) diagnosed with early-stage gastric cancer between December 2010 and December 2012. The team employed a dual-port method, using Covidien’s SILS port, a 5-mm flexible scope (Olympus, Japan) and surgical nylon with straight needles (Ethicon, Japan). Patients’ mean age was 68.1 years (range, 52-87 years) and body mass index was 21.4±4.5 kg/ m2. Average operative time was 266.9±38.3 minutes and blood loss was 37.8±56.8 mL. Patients recovered well and experienced no complications postsurgery. All

“I would be interested to know how many of the diabetics were no longer diabetic after a year.” —Jon Gould, MD placement of a DJBL can result in significant weight loss in both patients with and without type 2 diabetes, and that patients with higher baseline levels of HbA1cc could benefit from early intervention to optimize the weight loss effect of this device. Dr. Munoz also said that the baseline levels of HbA1cc in the group of patients with type 2 diabetes averaged 6.7%, which indicated good glycemic control and HbA1cc levels in the patients without type 2 diabetes averaged 6%. A larger trial could yield different results.

patients could tolerate soft meals on postoperative day 1 and had an average hospital length of stay (LOS) of eight days. Additionally, the authors reported no differences between the current SILS dual-port approach and the laparoscopic multiport method they performed on nine patients between 2008 and 2010, in terms of mean operative time (266.9±38.3 vs. 255.3±68.5 min., respectively), blood loss (37.8±56.8 vs. 55.4±57.1 mL, respectively) and retrieved lymph nodes (16.1±8.9 vs. 14.9±7.2, respectively). Postoperative hospital LOS, however, was significantly longer in the conventional multiport group (17.3±7.4 vs. 8.1±1.5 days; P<0.0001), and three patients in the conventional multiport group experienced complications (one case of postoperative pneumonia and two cases of gastric stasis). There were no complications in the dualport group. This study was nominated for the Olympus EAES Award for best oral presentation on single-port surgery. Although the benefits of SILS compared with conventional laparoscopic surgery have not been established through a head-to-head analysis, single-site surgery does show promise. In addition to cosmetic benefits, Dr. Kashiwagi concluded that a single-port approach to early gastric cancers may result in less postoperative pain and a shorter hospital LOS as well as a reduced chance of tissue trauma and complications associated with creating multiple ports, such as organ damage, bleeding, wound infection and hernias. Recently, Dr. Kim and his colleagues revealed the

“The differences in baseline HbA1c between diabetic and nondiabetic patients are not great, and I suspect that this relationship may disappear in a prospective trial with more patients,” said Jon Gould, MD, chief, Division of Surgery, Alonzo P. Walker Chair in Surgery and associate professor of surgery, Medical College of Wisconsin in Milwaukee. “The demographics of the study group suggest these patients would otherwise have been candidates for bariatric surgery. The mean weight loss seems pretty good for an entirely endoscopic procedure using an implantable device, so I think it is notable that the weight loss was so good,” Dr. Gould said. “I would be interested to know how many of the diabetics were no longer diabetic after a year.” Dr. Munoz and his team are currently analyzing several gut-derived peptides and important metabolites involved in body weight and glucose regulation from blood samples obtained in a fasting condition and after a standard meal test of DJBL recipients. The samples will be taken monthly for a year. “This new set of data will help us to have a better understanding of how this device impacts a patient’s physiology, and how these changes correlate with weight loss and metabolic outcomes,” Dr. Munoz said.

’We need to perform larger studies to confirm the advantages of this operation.’ —Hiroyuki Kashiwagi, MD results of their pure SILS approach to early gastric cancers, presenting their initial findings at the annual International Gastric Caancer Congress in Italy. Dr. Kim’s team reported similar operative times and morbidity as well as better short-term outcomes—including reduced postoperative pain, blood loss, and improved cosmesis—for single-incision distal gastrectomy compared with the conventional laparoscopic approach. According to Dr. Kashiwagi, more research is needed to make reduced-port surgery a standard approach in countries with high rates of early detection of gastric cancers. “We need to perform larger studies to confirm the advantages of this operation,” he said. Dr. Kim agreed, adding that advancing the single-port technique will involve further development of smart, articulated instruments and perhaps also robotic technology. Although still early, Dr. Kashiwagi believes that eventually “reduced-port surgery will become a standard therapy for early-stage gastric cancer, although not for advanced cancer.” Drs. Kashiwagi and Kim reported no relevant conflicts of interest.


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In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

More Overlap Means Fewer Hernia Recurrences Size and Placement of Mesh Key to Success B Y C HRISTINA F RANGOU ORLANDO, FLA.—When Karl LeBlanc, MD, MBA, FACS, a private practice general surgeon in Baton Rouge, La., performed the world’s first laparoscopic ventral hernia repair in 1991, he aimed for a mesh overlap of about 1 cm. Twenty years later, he shakes his head at the notion of a 1-cm overlap. A growing body of evidence suggests that a larger mesh overlap, along with symmetrical placement of the mesh, result in far fewer hernia recurrences, Dr. LeBlanc said at the 15th Annual Hernia Repair Meeting. “Increasingly, we’re looking at the more overlap, the better, when it comes to recurrence,” said Dr. LeBlanc, who has amassed one of the largest volumes of laparoscopic ventral and incisional hernia repairs in the world, with a total of more than 1,200 cases. At the meeting, Dr. LeBlanc said that currently, he believes that an overlap of 5 cm or more is optimal. He extends the overlap to as much as 8 cm in patients who are obese, who have several prior recurrences or who have hernias unusually high or low in the abdominal cavity. “The algorithm I have in my head is the bigger the defect and the more comorbidities, the more overlap you need,” he said. Over the past decade, it has become standard practice for surgeons to recommend a mesh overlap of at least 3 to 5 cm on all sides surrounding the defect. However, sparse robust data exist to back this up, so Dr. LeBlanc set out to evaluate this recommendation along with other technical factors that may affect the outcome of laparoscopic incisional and ventral hernia repairs. He reviewed the PubMed and

Cochrane Library scientific databases for the years 19992 to 2012, looking at all technical failurres leading to hernia recurrence. Overall, the review found little highquality evidence thaat focused on technical reasons for rep pair failures. Of 111 articles that addressed technical issues in hernia repairs, thee vast majority overlooked the question n: Only 16 of them adequately assessed the effect of mesh overlap. In these stud dies, recurrence rates ranged from 9% to 14.3% when mesh overlapped by 2 to 3 cm. Recurrences dropped substantially to between 0% and 7% with mesh overllap of at least 3 to 5 cm. The studiies included about 3,500 patientts with an average of 25.5 months of follow-up and a mesh overlap of 2 to 5 cm. In one of the largest est repo reportp rted series, an overlap of between 2 and 2.25 cm was associated with a recurrence rate of 9%. Recurrences dropped to 2% with an overlap of 4 cm or greater ((JSLS S 2008;12:51-57). “What we’re seeing is that increasing the overlap of the fascial defect to between 3 and 6 cm results in decreasing the recurrence rate by at least half,” Dr. LeBlanc said. Asymmetrical placement of the mesh was another contributing factor to recurrences, according to the literature review. Two studies linked failed repairs to inaccurate centering of the mesh or inadequate overlap on one side. Experts noted that the quality of the published studies in hernia surgery is “notably weak,” with a lack of grade A evidence and little uniformity across the published studies. Maciej Smietanski, MD, PhD, a hernia surgeon at the Medical University of Gdansk in Poland, said the report underscores a very important issue in hernia surgery, “that mesh overlap and the right

Experts noted that the quality of published studies in hernia surgery is ’notably weak.’ positioning are the key factors for success.” Dr. LeBlanc offered surgeons some technical tips to improve mesh placement in laparoscopic hernia repair. Surgeons must carefully measure both the defect and the mesh prior to surgery, and they should dissect any fat that could come in contact with the mesh. Dr. LeBlanc also recommended that surgeons place a camera on both sides of the abdomen to assess both sides of the mesh. He said that he places sutures on two axes of the mesh prior to placement in order to help with mesh placement. “You put the mesh in, then pull one side of the suture up and then the other suture up so you know it’s centered superiorly and inferiorly,” Dr. LeBlanc said. He also said new mesh-positioning

devices such as the Echo PS™ by Davol Inc., and AccuMesh™ Positioning System by Covidien, can help with accurate placement. The conclusions of the review were similar to those in a retrospective study published last year in the Journal of Surgical Researchh (2012;177:e7-e13). Investigators from Baylor College of Medicine reviewed the outcomes of 201 patients who underwent laparoscopic ventral hernia repair between 2000 and 2010. They said potential solutions to the problem of mesh shift include increasing mesh overlap to 6 cm or greater, transcutaneous closure of central defect, securing transfascial sutures before tacking, placing operative side tacks first, and possible placement of contralateral ports to secure the mesh. Dr. LeBlanc is a speaker/consultant for Covidien, Davol Inc., and W.L.Gore & Associates. He also has received a research grant from Cousin Biotech Inc.,/Medline and is a shareholder in Via Surgical Ltd.

Group Identifies Risk Factors for Ventral Hernia Site Occurrences B Y C HRISTINA F RANGOU

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risk assessment model has found several modifiable intraoperative practices that increase risk for surgical site occurrences after open ventral hernia repair. These practices include use of skin flaps, singlestage repairs for hernias that are actively infected and improper placement of mesh. “High-risk patients undergoing complex ventral hernia repairs are probably enduring one of the hardest and most difficult surgeries that they will ever

experience in their lives,” said senior author Mike Liang, MD, assistant professor of surgery, Baylor College of Medicine, Houston. “Patients in this high-risk group may benefit from a modified surgical technique.” Rachel Berger, a student for a master of public health degree, presented the findings at the 2013 annual meeting of the Surgical Infection Society, held in Las Vegas. This is one of the first studies to address the incidence and risk factors, including intraoperative factors, for surgical site occurrences following open ventral hernia repair. Donald E. Fry, MD, executive vice president of

Michael Pine and Associates and adjunct professor of surgery at Chicago’s Northwestern University, said the study “will hopefully provide us with some direction on how we are going to be able to optimize outcomes for quite a morbid operation.” More research is needed, he added, to assess all factors that play into infection risk, particularly admission laboratory results. The risk assessment model will require validation at other institutions. Dr. Fry, an expert in risk assessment modeling, said the study represents some of the highest-quality research to address infections in ventral hernia. Previous projects from the Ventral Hernia Working


In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Group, a corporate-sponsored group of hernia experts in the United States, and the National Nosocomial Infections Surveillance system identified multiple factors predicting patients at higher risk for surgical site occurrences or infections. These risk assessment tools, however, were incomplete, said Dr. Liang. They were not based on direct patient data, not specific to ventral hernias or failed to provide adequate stratification of hernia patients. Dr. Liang and his colleagues set out to create a prognostic ventral hernia risk score based on direct patient data. They conducted a retrospective study of 888 patients who underwent open ventral hernia repair at a single institution between 2000 and 2010. Their study examined all surgical site occurrences to ensure all wound complications were captured. Surgical site occurrences were defined as surgical site infections; formations of a seroma, hematoma or fistula; or wound dehiscences. In all, one-third of the patients developed 415 unique surgical site occurrences. The most common occurrence was a surgical site infection (21.6%), followed by seroma (12.1%), wound dehiscence (7.1%), hematoma (3.0%) and fistula (1.4%). The investigators conducted a multivariate analysis using internal resampling to identify independent risk factors for surgical site occurrences. Their methodology ensured greater external validity and applicability of the model to external data sets. Each risk factor was assigned a numeric value based on the odds ratio, and a clinical risk score for each patient was calculated based on these factors. The presence of a class 4 wound significantly increased risk for surgical site occurrence, with an odds ratio of 8.7 (95% confidence interval [CI], 3.7-24.1; P<0.001). Investigators assigned nine points to the presence of a class 4 wound, making it the most important factor in the Ventral Hernia Risk Score. (In the National Nosocomial Infection Surveillance risk index, a class 4 wound is worth only one point, making it the same as the American Society of Anesthesiologists' score 3.) Three other variables were found to significantly increase ventral hernia risk: the creation of skin flaps, incidental or concomitant hernia repair and the implantation of mesh. Each of these variables was worth two points in the risk score. The investigators grouped patients into three categories based on their risk score: Class I, zero points; Class II, 2 to 4 points; and Class III, three or more points. Nearly 80% of patients categorized as Class III in the study developed a surgical site occurrence, compared with 49.6% of patients in Class II and 17.8% in Class I. Dr. Liang said he and his colleagues now use the risk score in their assessment

of patients with ventral hernia. They employ preoperative and intraoperative techniques to reduce the risk in patients likely to develop a surgical site infection or an occurrence. Patients are encouraged to lose weight, stop smoking and improve diabetes control. In patients with wound class 4, surgeons attempt to reduce the pathology and stage repairs rather than perform singlestage repairs. They avoid use of skin flaps whenever possible, Dr. Liang said. They carefully select mesh, â&#x20AC;&#x153;as the mesh will invariably come into contact with bacteria in complicated ventral hernia repair.â&#x20AC;?

The presence of a class 4 wound significantly increased risk for surgical site occurrence, with an odds ratio of 8.7. Some patients should be considered for watchful waiting instead of surgery, Dr. Liang said. The authors used a receiver operating characteristic analysis to compare the Ventral Hernia Risk Score with the risk assessment tools from the Ventral Hernia

Working Group and the National Nosocomial Infection Surveillance system index. The analysis showed the Ventral Hernia Risk Score for accurately predicting surgical site occurrence exceeded other tools. The investigators are organizing follow-up studies to externally validate their results. Dr. Liang disclosed that he receives a LifeCell research grant and unrestricted educational grants. Dr. Fry disclosed that he is on the speakersâ&#x20AC;&#x2122; bureau for Merck, and has served as a consultant for Ethicon.

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GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Investigational Device Prolongs Survival of Livers for Transplantation May Increase Availability Of Donor Livers B Y V ICTORIA S TERN

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atients who need a new liver to survive must hope that they are one of the approximately 13,000 liver transplant recipients in the United States and Europe each year. But with 30,000 people on waiting lists, and with only ice keeping livers for transplantation viable for up to 14 hours, the odds are not always in the patients’ favor. Each year, more than 2,000 livers don’t survive the journey to their new home. “Preserving organs by cooling them down is far from perfect,” said Peter J. Friend, MD, director of transplantation surgery, Nuffield Department of Surgical Sciences, Oxford Transplant Centre, U.K. “Although cooling the organ on ice slows its metabolism by a factor of 10, the liver continues A liver 30 seconds after connection to the OrganOx Metra device. Parts to metabolize slowly and deteriorates as a result. of the organ are still cold, while other parts are warm and perfused with It’s hard to tell which organs will work and which red cell solution. ones won’t.” Now, however, Dr. Friend and his colleague Constantin Coussios, PhD, professor of biomedical engineering at the University of Oxford, have devised a novel technology that may be a game changer: A machine that allows the liver to function for up to 24 hours, as though it were still inside a human body. On March 15, the team of engineers and physicians announced the preliminary success of this machine, which has safely transported livers to two transplant recipients at King’s College Hospital in London. “The first two cases went very well,” said Dr. Friend. “They weren’t exceptionally high risk, but the machine did what it was supposed to do.”

Long Time in the Making In 1994, Drs. Friend and Coussios devised the idea for the technology, but faced several engineering challenges while developing it. The co-inventors needed to create an artificial environment that could simulate the key functions of the human body, including pumping blood and providing nutrition to the organ. These functions not only had to be automated to make it possible for transplant surgeons around the globe to use the technology, but also small enough for easy transportability. After 15 years of developing and tweaking the design, Drs. Friend and Coussios have created a technology that appears to meet these requirements. The liver’s main blood vessels are connected to tubes on the machine, which automatically regulate the environment around the liver. The device maintains the liver at body temperature and infuses it with oxygenated red blood cells, nutrition such as glucose and amino acids, and other chemicals to create a physiologic environment that mimics the human body. The liver is not only kept alive, but it continues to produce bile as well. Additionally, the machine is compact. “It’s about the size of a supermarket trolley [shopping cart], which means it can go in

The liver 5 minutes after connection to the OrganOx Metra, now fully perfused and at physiologic temperature.

The King’s College Hospital, Oxford University and OrganOx team successfully connects the first human liver for transplantation to the OrganOx Metra device.

back of ambulance, small plane or helicopter,” Dr. Friend said. “Size was very important because we knew there was no point in making a machine if it couldn’t fit in the back of a vehicle.” Notably, the machine also may allow the liver to recover from injuries it sustained during or before removal, Dr. Friend pointed out. This function of the device is particularly important because it could expand the number of viable livers for transplantation. In recent years, the demand for livers has grown, as liver disease has become more common, whereas the quality of donor livers has diminished. “More and more, donors tend to be older, and have a high body mass index or coexisting major health problems,” Dr. Friend noted. “Because of the increasing demand for livers, we are having to use organs we would have once said no to.” Now with the machine, transplant surgeons can test how well the liver is working during preservation. “If the liver works on the pump, then we can assume it will work in the recipient,” said Maria B. Majella Doyle, MD, MBA, associate professor of surgery at Washington University School of Medicine, St. Louis, who specializes in liver transplantation. Dr. Doyle was not involved in developing this pump, but she is performing research to develop a different liver pump system, one that also keeps the liver at physiologic temperature. In April 2008, Drs. Friend and Coussios cofounded a company called OrganOx Ltd., to continue their University of Oxford research. With financial support from the Royal Society and several venture capital funds in the United Kingdom, the company has been working to bring the technology to patients. Although promising, the device still needs more testing. The U.K. team has begun a pilot trial at King’s College Hospital to test the ability of the machine to transport livers to 20 transplant patients. If the trial is successful, OrganOx then could apply for marketing authority, which would make the device commercially available in Europe. “If the machine is as good as we believe, we would expect a significant increase in patients who get liver transplants,” Dr. Friend said. According to Dr. Doyle, the group is “ahead of the game.” To her knowledge, two other teams are developing physiologic-temperature liver pump systems—Dr. Doyle and her colleagues William Chapman, MD, and Vijay Subramanian, MD, at Washington University, and Constantino Fondevila, MD, PhD, at the University of Barcelona—but both are at more preliminary stages. “The U.K. team is the first to produce human data with the pump and show it’s safe and viable as a liver transplantation device. Now, it’s important to make sure the technology is foolproof and cost-effective,” Dr. Doyle said. “The U.K. team needs to be highly commended. The pump is a great achievement.”


In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

ULTRASOUND

jcontinued from page 1 read the CT results. Analysis showed the DASH examination accurately identified incisional hernias, with a positive predictive value of 91% and negative predictive value of 97%. Moreover, DASH exams identified clinically apparent hernias missed by surgeon-interpreted CT. Unlike CT, DASH can be performed without exposing patients to ionizing radiation. Additionally, DASH provides real-time results available to both the surgeon and patient for clinical decision making. Speaking at the 2013 Annual Hernia Repair Meeting in Orlando, Fla., Dr. Poulose said DASH has the potential to change clinical practice and significantly improve research in the field of hernia. Currently, no reliable, cost-effective means of detecting hernias exists. “Using clinical exams alone, we may be missing 20% to 30% of recurrences, and follow-up CT scanning is prohibitively expensive with a concomitant radiation risk. DASH could easily facilitate longterm follow-up of hernia patients,” said Dr. Poulose. The patients studied had a prior abdominal or pelvic operation performed via incision of the anterior abdominal wall. All had a viewable CT scan of the abdomen and pelvis in the six months before enrollment in the study. A surgeon who successfully completed the American College of Surgeons Ultrasound for Surgeons Basic Course performed DASH. DASH results were then compared with the gold standard, surgeon-interpreted CT, along with the clinical exam results and radiologist interpretations of the CTs. DASH exams revealed 107 incisional hernias, including four missed by the surgeon-interpreted CT scans. All missed hernias were in patients with “fairly thick” hernia sacs that were difficult to distinguish radiographically from healthy adjacent fascia, although these hernias were clinically obvious. As well, DASH identified 28 incisional hernias in patients who were deemed not to have hernias based on history and physical exam alone. The most challenging hernias to detect with DASH were small umbilical hernias in obese patients. Investigators said CT could help with diagnosis in difficult situations. The U.S. machine varies in cost between $15,000 and $30,000, depending on its age and its features. Investigators argue that clinical practices can offset the cost through billing for the procedure itself. Surgeons also can use machines already installed in their practices by adapting the machines to evaluate the anterior abdominal wall, said

investigators. They caution, however, that practitioners need to meet the credentialing and billing requirements of their institution. Internal data from Vanderbilt indicates that about 100 DASH exams need to be performed to recoup the initial cost of the machine and maintenance fees. Robert J. Fitzgibbons Jr., MD, professor of surgery and chief of general surgery at Creighton University in Omaha, Neb., said the DASH test appears to be a viable option but may have difficulty gaining widespread acceptance. “There are two limitations to adoption

of this technology: the large up-front outlay of cash required to purchase the hardware and the fact that ultrasonography really has not caught on with surgeons. “I’ve thought throughout my career that ultrasonography would play a much larger role in general surgery practice. It is a natural. The surgeon has a unique perspective in that the examination can be obtained and the findings unequivocally confirmed or denied with a subsequent open procedure. … But it has never really caught on outside of breast surgery. I sometimes wonder if surgeons have trouble thinking in the

two-dimensional world of ultrasound while working in the three-dimensional environment of surgery.” DASH requires formal training via the American College of Surgeons Ultrasound for Surgeons Basic Course. Seventeen patients in the study were evaluated to assess interrated reliability with three surgeons performing DASH and evaluating the corresponding CT images. Identical results were obtained for two surgeons, with discordant results found in three patients with the third surgeon.

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GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

New Colonoscope Offers Sweeping, 330-Degree Views of the Colon B Y A UDREY A NDREWS ORLANDO, FLA.—A new colonoscope that provides three simultaneous fullspectrum images of the colon detected significantly more adenomas—and missed significantly fewer—in findings presented at the 2013 Digestive Disease Week (DDW) meeting. Ian M. Gralnek, MD, MSHS, associate professor of medicine/gastroenterology at the Rappaport Family Faculty of Medicine Technion-Israel Institute of Technology in Haifa, Israel, presented data on the Fuse Full Spectrum Endoscopy (Fuse) system in a study that compared the new technology with traditional, forward-viewing (TFV) colonoscopy in a tandem endoscopy study design. “Compared with TFV colonoscopy, Fuse found significantly more adenono mas, had a significantly lower adenooma miss rate and impacted colonoscopy surveillance recommendations,” Dr. Gralnek said. “Our results are very compelling. We believe that Fuse is an advance in colonoscopy technology.” At a press briefing, Dr. Gralnek indicated that interest in the technology at the meeting had been “huge.” Dr. Gralnek said, “We are all becoming aware that we miss adenomas. We need to do a better job at finding them, and we need better teechnology for this.” The Fuse system, developed by EndoChoice, shares similar technical features of standard colonoscopes but allows a 330-degree view of the colon, much broader than the 170-degree viewing angle of traditional colonoscopes. The Fuse colonoscope employs multiple imagers and projects the expanded view on three corresponding screens, instead of the one display used with TFV. With TFV, up to 31% of adenomas can be missed, primarily due to inadequate visualization of the proximal side of colonic folds and anatomic flexures within the colon (World J Gastroenteroll 2012;18:3400-3408). The Fuse system fulfills the need for technology that will expand visualization, Dr. Gralnek said. In the randomized, multicenter trial, investigators followed a tandem colonoscopy design in which same-day, back-toback colonoscopies using Fuse and TFV were performed by the same endoscopist. Dr. Gralnek presented results on 185 patients, whose indications for colonoscopy included screening (55.7%), surveillance (19.5%) and diagnostic evaluation (24.8%). Among 88 patients who received TFV as their initial colonoscopy followed by

Fuse, 28 adenomas/cancers were detected on the first pass with TFV, and an additional 20 adenomas/cancers were detected on the second pass using Fuse. “This amounted to a 71.4% increase in the number of adenomas found with Fuse,” Dr. Gralnek reported. In contrast, among 97 patients initially scoped with Fuse, 61 adenomas/cancers were found on the first pass with Fuse, and only five additional adenomas were seen on the second pass with TFV, for an 8.2% increase in adenoma detection via the conventional approach. The difference in this comparison was statistically significant (P<0.0001). Significant differences also were observed in rates of missed adenomas and false-negatives. Additionally, the adenoma detection rate (ADR) per colonoscopy type at first colonoscopy was numerically, but not significantly, improved with Fuse.

described the “feel” of the new device, specifically the three-screen viewing system. “I have done about 75 cases myself, and I became comfortable using Fuse after about five cases. I focus on the center video monitor, and my peripheral vision picks up polyps that appear on the side monitors. It’s very intuitive.” The findings could theoretically change surveillance recommendations for some patients. Of the 15 patients who had the 20 missed adenomas with TFV, the use of Fuse changed their colonoscopy surveillance schedule—the interval for followup colonoscopy was shortened for 53.3% of those patients. David Lieberman, MD, professor of medicine and chief of the Department of Gastroenterology and Hepatology at Oregon Health & Science University, in Portland, called the Fuse system a “very very exciting technology.”

Table. Outcomes in Patients Undergoing Tandem Colonoscopy With TFV Versus Fuse TFV

Fuse

P Value

Additional adenomas detected (per lesion)

8.2%

71.4%

P<0.0001

Adenomas missed (per lesion)

41.7%

7.6%

P<0.0001

False-negative colonoscopies (per patient)

5.7%

0%

P=0.02

ADR per colonoscope type at first colonoscopy

27.3%

33.0%

P=0.40

ADR, adenoma detection rate; Fuse, Fuse Full Spectrum Endoscopy; TFV, traditional, forward-viewing colonoscopy

Dr. Gralnek noted that the study was powered as a per-lesion analysis and not as a per-patient analysis; therefore, perpatient ADRs could not be statistically evaluated. More than 1,000 patients would need to be studied to evaluate ADR as an end point on a per-patient basis, he explained. Most of the 20 adenomas that were initially missed by TFV in the study were sessile lesions in the right colon, primarily tubular adenomas, 1 to 5 mm. The five adenomas missed by Fuse on the initial pass were all sessile lesions, tubular subtype and 1 to 5 mm in diameter; two were located in the right colon, and three were in the left colon. Discussing the Fuse system at the DDW press briefing, Dr. Gralnek

Dr. Lieberman drew an analogy between using the Fuse system and driving a car: “You look out your front window, but you can also see things out of the side windows, too, such as a pedestrian standing on the curb,” he explained. “That could be a polyp, and you can see what angle you need to have in order to make your turn.” He said the findings from the comparison study “suggest that you may see more polyps” using Fuse. Frank Sinicrope, MD, professor of medicine and oncology at Mayo Clinic, Rochester, Minn., also acknowledged the advantages of the device over TFV. “It is acknowledged that a major limitation of our current forward-viewing colonoscopes is that they do not allow

visualization behind mucosal folds, which can result in missed polyps, or even cancers. This limitation is an important factor that reduces the effectiveness of colonoscopy for cancer prevention,” he noted. The study by Dr. Gralnek showed Fuse to be superior to TFV for the detection of adenomas, with significantly fewer missed adenomas, Dr. Sinicrope added. Because ADR is a key quality metric, these are “important data,” he said. However, more information is needed regarding the risk features of these adenomas, he said. It is also important to determine if Fuse can increase the detection of flat polyps because these lesions may lead to interval cancers and contribute to the observed reduction in efficacy of TFV in the right versus the left side of the colon. “This will be important to demonstrate in future studies,” he said. He added that although Fuse could represent a true advance, it also might detect more adenomas and polyps that are simply harmless. “Detecting more polyps and adenomas does not necessarily indicate that a reduction in cancer risk or mortality will result. Many small adenomas may never develop into cancers, whereas the detection and removal of advanced adenomas is expected to translate into the prevention of future cancers. However, better adenoma detection and complete removal are necessary steps for colorectal cancer prevention. “Despite these issues,” he said, “the Fuse colonoscope represents an important advance in endoscopic technology that improves ADR, and thereby the efficacy of colonoscopy.” Colleen M. Schmitt, MD, of Galen Gastroenterology in Chattanooga, Tenn., who moderated the DDW press conference, noted that the miss rate in the control group was “at the top of the reported range,” which could exaggerate the differences between the two approaches. However, she added, a difference of even half of what was reported would be “important.” Dr. Schmitt, who is president-elect of the ASGE, said that the findings should be replicated in a community setting, pointing out that the 71% increase in the number of adenomas found was achieved “by expert hands.” Studies are needed, she said, to determine the ADR with Fuse “in the hands of general practitioners,” although she predicted the outcomes “will probably be better than what we are achieving now.” Dr. Gralnek has served on an advisory committee or review panel for Given Imaging and Motus GI, and has served as a consultant for AstraZeneca, Given Imaging and PeerMedical.


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In the News

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Single-Incision Laparoscopic Cholecystectomy Linked to Higher Hernia Rates B Y G EORGE O CHOA

I

n a head-to-head comparison, patients undergoing single-incision laparoscopic cholecystectomy had a significantly higher rate of hernia formation at oneyear follow-up than those having standard four-port laparoscopy. Only one of 81 patients who received standard laparoscopy developed a hernia (1.2%) versus 10 of 119 patients (8.4%) who underwent the single-incision procedure (P=0.03). P “I was somewhat surprised by the results,” the study’s lead author, Jeffrey M. Marks, MD, FACS, FASGE, told General Surgery News. “But as you make incisions larger, there is a greater consequence of hernia.” Dr. Marks is professor of surgery at University Hospitals Case Medical Center, Cleveland. Steven Schwaitzberg, MD, FACS, chief of surgery, Cambridge Health Alliance, and associate professor, Harvard Medical School, Boston, who was not involved in the study, said in an interview: “In many ways, this is a landmark paper because it’s going to drive clinical practice.” The study, published in the Journal of the American College of Surgeonss (2013;216:1037-1047) was sponsored by Covidien, manufacturer of the SILS Port, a device used in single-incision laparoscopic cholecystectomy. According to Dr. Marks, Covidien was “fully transparent, and above all wanted to assure that they didn’t influence the study.” In an invited commentary accompanying the study, David W. Rattner, MD, FACS, wrote, “Covidien Inc., and the authors are to be congratulated both for performing the study properly and publishing results that were not necessarily what the corporate sponsor might have hoped for.” In the prospective, multicenter, single-blinded,

GASTRIC BYPASS jcontinued from page 1

patients who regained weight after gastric bypass surgery complained of intermeal hunger, especially following meals rich in simple carbohydrates. “Consistent with that is the fact that there are new conditions—nesidioblastosis, noninsulinoma pancreatogenous hypoglycemia syndrome, hyperinsulinemia and hypoglycemia—[that are] becoming more common after gastric bypass,” Dr. Roslin said. “These are entities surgeons rarely encountered previous to this [era in bariatric surgery].” The research was presented at the 2013 meeting of the Society of American Gastrointestinal and Endoscopic Surgeons; the study was sponsored by Covidien. Dr. Roslin and his team decided to compare glucose metabolism among patients who had undergone gastric bypass, sleeve gastrectomy or duodenal switch (DS), in which a common channel of at least 125 cm was preserved.

controlled trial, 200 patients were randomized to singleAlthough the study is now closed, Dr. Marks, who is incision (n=119) or standard (n=81) laparoscopic chole- also director of surgical endoscopy and program direccystectomy. All patients at the 10 sites had biliary colic tor, Case Medical Center, said, “It would be nice to with documented gallstones or polyps, or had biliary reassess the patients in three and five years, and see if dyskinesia. The primary end points were feasibility and the difference in hernia formation is greater or if it has safety. Follow-up at 12 months was completed by 100 equilibrated.” patients (84%) in the single-incision group and 64 (79%) For now, Dr. Schwaitzberg, who is also past president, in the standard laparoscopy group. Society of American Gastrointestinal and Endoscopic Adverse events and severe Surgeons, said, “The data support ’In many ways, this is a adverse events did not difthe continued use of multiport surfer significantly between the gery for cholecystectomy since the landmark paper because two groups. Four wound-related hernia rate is lower.” it is going to drive clinical complications were reported in Dr. Marks noted, “Cosmesis was the standard laparoscopy group improved for the single-port group. practice.’ (4.9%) and 14 were reported in That is one of our goals with any —Steven Schwaitzberg, MD surgery, but an effective surgery the single-incision group (11.7%), but the difference was not statiswith minimal complications is the tically significant (P=0.13). P Pain greater goal.” scores were higher in the singleDrs. Marks and Schwaitzberg incision group than for standard reported no relevant financial conlaparoscopy at nearly all meaflicts of interest. sured points, but the difference in most cases was not statistically significant. Cosmesis scores favored singleincision over standard laparoscopy at all time points (P<0.0004). Physical quality-of-life scores favored standard laparoscopy over single-incision n laparos laparoscopy at some time points (dayy 3, P=0.01; one week, P=0.03; P one month, P P=0.03), but were equivalent at all other time poin nts. The two groups did not differ with respect to mental quality-of-life scoress. At all time points, more than 92% of patie patients preferred single-incision laparoscopy if they needed a cholecystectomy again (P<0.0001).

“This type of model gives us the ability to compare two operations that preserve the pyloric valve, as well as two operations that have an intestinal bypass component,” he said. In the prospective, nonrandomized study, 13 patients received gastric bypass, 12 received sleeve gastrectomy, and 13 underwent DS. All completed an oral glucose tolerance test (GTT) at baseline and six, nine and 12 months. The nine-month GTT comprised a solid mixed-meal muffin. The only significant, preoperative difference among the patients was greater body mass index in the DS group. There were no significant differences in their glucose homeostasis parameters, fasting glucose or insulin. At 12 months, the DS patients lost significantly more weight than the other two groups, although those also experienced good weight loss. All of the operations reduced fasting blood glucose levels as well. But after GTT, the gastric bypass group had much higher levels of one-hour glucose than the DS group,

and the sleeve gastrectomy group had intermediate levels. The gastric bypass group also had higher one-hour insulin levels, higher even than their preoperative level, whereas insulin was suppressed in the DS group. “When you have high insulin, glucose falls, and we know that hypoglycemia causes hunger,” Dr. Roslin said. “Looking at the one- to two-hour glucose ratio, the gastric bypass patients have the highest one-hour sugar [levels] and the lowest two-hour sugar [levels], and I think this begins to explain why we have intermeal hunger with gastric bypass.” All of the operations resulted in significant weight loss and other positive outcomes, but compared with gastric bypass patients, DS patients had a much smaller rise in one-hour glucose and insulin levels. “The sleeve behaves intermediately to the bypass and DS, meaning that preserving the pylorus may be part of the explanation, but not the whole story,” Dr. Roslin said. “Obviously, controlled trials between

gastric bypass and DS are needed to determine the real long-term significance, but I think we should all be cautious before we label gastric bypass the gold standard operation,” he said. Kevin M. Reavis, MD, FACS, esophageal and foregut surgery, Division of Gastrointestinal and Minimally Invasive Surgery, The Oregon Clinic, Portland, said that improved assays are allowing for a more rapid and better understanding of the true complexity of the physiologic changes that contribute to the results seen with each of the bariatric procedures. “This study highlights aspects of glucose metabolism that have previously been underappreciated.” “Although it is a relatively small study, it illustrates that with gastric bypass, sleeve gastrectomy and duodenal switch, there are substantial metabolic changes we are just beginning to understand and must investigate on a larger scale in order to optimize clinical outcomes,” Dr. Reavis said.


Clinical Review

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

Postoperative Pain Management in Anorectal Surgery New Techniques: Antidotes or Anecdotes?

B Y G ARY H. H OFFMAN , MD S TEPHEN Y OO , MD

AND

L OS A NGELES C OLON AND R ECTAL S URGICAL A SSOCIATES

A

norectal surgery: often a painful cure; and worse, the performance of the curative operation is only 50% of the battle. Sleepless nights await both the patient and the surgeon once the cure has been inflicted. Postoperative pain relief represents the other 50% of the battle. Thirty-five million ambulatory surgical procedures are performed annually in the United States.1 Effective pain control is essential for recovery, improved wound healing and reduced hospital admission rates. In evaluating hospital admission data for 20,817 patients undergoing same-day surgery, 1.5% returned to the hospital in the postoperative period.2 Pain was the most common reason. There has been little progress in addressing this challenge.

Can We Do Better? Surveys from 1993, 2003 and 2012 have demonstrated that postsurgical pain is common and that a similar distribution of the quality of perceived pain has remained unchanged.3-5 Patient pain scores are now being used as metrics in measuring the adequacy of care. Surveys from the Hospital Consumer Assessment of Healthcare Providers and Systems during 2008 and 2009 confirmed the need for improving postoperative pain management. Mean pain management scores were 68 of 100 in 3,765 participating hospitals. The government and other third-party payers may use data of this type in determining reimbursement rates. Surgeons and hospitals alike are being pushed to demonstrate improvement.

Educating Patients Several areas of improvement can help to reduce postsurgical pain. A first line of defense involves managing patient expectations. Patient education goes far in this regard. Preoperatively, patients should be advised that their postoperative discomfort may occur along a spectrum of intensity and that their pain intensity and frequency may change constantly until healing is final. Allowing patients to â&#x20AC;&#x153;prepare for the worstâ&#x20AC;? actually helps with

their expectations rather than hinders them. A frank discussion about postoperative pain management options reassures patients and helps them to understand that relief is available. With the advent of newer pain management techniques, procedures are available that may allow for sophisticated postoperative strategies to handle any discomfort. Transdermal patches, epidural injections and new oral pain medications are but a few strategies that will allow the patient and the surgeon to sleep in the days and weeks following anorectal surgery. A preoperative consultation with a pain management specialist mayy be worth its weight in sleep. Initiating the use of stool softeners before the opeeration may help in easing the pain of th he first postoperative bowel movem ment.

for prolapse and hemorrhoids (PPH) and transarterial hemorrhoidal dearterialization (THD) have been associated with diminishing, although not vanishing, postoperative pain. Procedures such as these are performed proximal to the dentate line and result in less pain because of the paucity of pain fibers in this region. These procedures require careful patient selection and are best suited for stage II/ III hemorrhoids with prolapse and a limited external hemorrhoidal component. When PPH and THD are compared with ith the th Milligan-Morgan Milli M ttechnique h i ffor

To date, 100% of our patients have been almost pain-free for the entire sixday period. Opioid use has been minimal both during the six-day period and after the sixday period. Educating the Opeerating Team

Lip oso me

Urinary retention is the h bbane off the h anorectal surgeon. The discomfort of urinary retention adds to the pain from the operation. It is recommended that the operation be performed using a safe but limited volume of IV fluids. Should retention be encountered postoperatively, an attempt to void while sitting in a warm tub may be all that is necessary to achieve symptomatic relief. However, prolonged urinary retention may worsen matters and might indicate a more serious underlying problem. Patients should be instructed to contact their surgeon earlier rather than later in their course.

Educating the Surgeon Another area of improvement has evolved through the efforts of surgeons and industry working together to develop less traumatic procedures. An example of this collaboration has been in the area of the hemorrhoidectomy. Procedure

stage IV h hemorrhoids, h d the h d duration and d depth of pain after the excisional hemorrhoidectomy (Milligan-Morgan technique) is typically longer and more severe. Although considered to be an advance in hemorrhoidal operations, the adoption of these newer techniques has been slow because special training is required. Traditionally, multimodality and multidisciplinary pharmacologic techniques have been used to help in the management of the patientâ&#x20AC;&#x2122;s recovery. Opioids have been a cornerstone in the management of postoperative pain. However, narcotics may be accompanied by numerous well-known adverse events (AEs) such as nausea, vomiting, constipation, respiratory depression, ileus, itching and dependence/tolerance. AEs related to opioids have been reported in 12% to 48% of patients.6 In the inpatient setting, opioid-related AEs account for a 3.3-day increase in hospital length of stay.

Several options exist to help decrease the dependence on narcotics. Nonsteroidal anti-inflammatory drugs (NSAIDs) and acetaminophen (APAP) have been shown to help control postoperative pain. NSAIDs may be started before surgery and continued through the recovery period. Many studies have demonstrated a diminution in pain scores when up to 1,000 mg of APAP, 600 mg of ibuprofen or 30 mg of intravenous ketorolac were given immediately after surgery.7 NSAIDs aid in reducing and managing the inflammatory response. Cyclooxygenase-2 inhibitors,, ketamine, clonidine and steroids also havve demonstrated benefit. Many surgeonss have patients begin taking NSAIDss preoperatively and continue taking the medication throughout the recovery period. As N NSAIDs may be associated with postoperative bleedin ng, their use must be evaluaated with a preoperative aassessment of various patieent risk factors. Some S institutions are using gabapentin n/pregabalin in faast-track recovery prrotocols for abdomin nal surgery. Several sttudies have demonstrrated that administeering 1,200 mg of gabaapentin or 300 mg of pregab balin preoperatively yields a decrease in adjunctive narcootic requirements.8 Some surgeonss will administer the medication for up to two to three days postoperatively. Larrger doses have been associated d with h sedation d and dizziness. There are no established studies evaluating the use of these medications after anorectal surgery. Anecdotal reports abound, however, testifying to their effectiveness. This is an area ripe for larger, randomized trials.

Local Pain Control: The Basics Any anesthetic agent that is able to inhibit the excitatory process in the nerve ending will block the perception of pain. The nerve membrane is a lipid and protein structure. The two key elements in pain control are the anesthetic potency and duration of action. These are related to the lipid and protein structure of the nerve membrane. Anesthetic potency is correlated with lipid solubility. Anesthetic duration is related to the degree of protein binding at the membrane level, with a longer duration of anesthesia being the see PAIN MANAGEMENT page 14

13


14

Clinical Review PAIN MANAGEMENT jcontinued from page 13

result of a greater binding activity. Both pH and the type and size of the nerve fibers also play a role in the anesthetic effects of various agents. Local anesthetics are more effective in more basic pH environments. Smaller nerves with lighter myelin coatings are more easily blocked than are larger, more heavily myelinated nerves. Pain is most commonly the first sensation to be blocked and the last to recover, followed by temperature sensation, touch and pressure. Anesthetic agents can be degraded by hydrolysis or by enzymatic activity. As bupivacaine is metabolized slowly, its anesthetic effects are longer lasting. Lidocaine is rapidly metabolized and is a short-acting agent. These two drugs are the most common local anesthetic agents used in anorectal procedures. Local anesthetics are used routinely and are extremely effective for completely blocking pain sensation intraoperatively. Administered in the form of a pudendal block, coupled with direct injections into the operative sites before beginning the operation, local anesthetics also are effective in managing pain in the postoperative setting. Their benefit, however, is limited by their duration of effectiveness. Bupivacaine and lidocaine have established durations of action of less than 12 hours, even with the use of epinephrine. Because of this, there have been attempts to improve the duration profile of local anesthetics. Elastomeric pain pumps and catheter systems have been shown to help ameliorate the pain for several days postoperatively. Ideally, the pumps should deliver a steady dose of the anesthetic for one to seven days, depending on the size of the pump. However, there have been technical problems reported, including catheter dislodgement and infections.9 Epidural anesthesia is a reliable way to ensure a pain-free postoperative recovery. The catheters can remain in place for up to five days after a procedure. Although most often used in the hospital setting, it is theoretically possible to use this type of system on an outpatient basis. Adoption of this technique has been hampered by the need for periodic infusion of the anesthetic, catheter dislodgement, various systemic side effects and the potential for a delay in the diagnosis of a possibly serious catheter-related infection. The topical application of local anesthetics is of marginal and unpredictable efficacy.

A Leap Forward? More Basics Liposomal depot formulations of bupivacaine have shown promise in the management of postoperative pain.10,11 Liposomes are laboratory-prepared,

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

microscopic lipid bilayer membranes that encapsulate an aqueous core. A lipid bilayer is essentially a double-thickness layer of phospholipid molecules. Each of the two layers is one molecule in thickness. This dual-layer system is common in nature and serves to keep substances positioned where they are needed, thus preventing these substances (proteins or ions) from diffusing away from their target area. Cell membranes are composed of lipid bilayers. The idea behind using a liposomal system is that the liposomes can be formulated into a multivesicular system, with the active anesthetic agent being held in each vesicle and slowly released to the target area over time. The anesthetic agent, bupivacaine, is not new; the delivery system is the apparent innovation. The anesthetic system is marketed under the name of Exparel (Pacira Pharmaceuticals). The microvesicular liposomal preparation theoretically results in a drug release pattern showing an increased stability and a prolonged duration of medication release. The pharmacokinetics result in a sevenfold increase in the Tmax, and a 9.8 times increase in the half-life of the medication. The manufacturer states that the medication has a duration of up to 72 hours of delivery and effectiveness. The onset of action is immediate, as there is free bupivacaine in the solution along with the microvesicular preparation.

The Antidote?

of 66 to 532 mg (with the FDA-approved dose at 266 mg), and cardiac safety has been demonstrated in supratherapeutic doses as high as 665 mg in healthy volunteers. Studies evaluating ER bupivacaine in the setting of open and laparoscopic colectomies, ileostomy reversal, breast augmentation, inguinal hernia repairs and total knee replacement demonstrated similar favorable results.13-17 It seems that the medication may be of benefit in many procedures requiring the use of local anesthesia.

Practical Considerations Liposomal bupivacaine comes in single-use 20-cc vials containing 266 mg of bupivacaine that must be stored between 36 F and 46 F. A temperature indicator will change from green to white if the medication has been exposed to excessively low or high temperatures. The medication may be stored at room temperature for up to 30 days. The liposomal structure may be altered if the preparation is exposed to lidocaine or other anesthetics and liposomal bupivacaine should not be mixed with other preparations. Liposomal bupivacaine may used without dilution or may be mixed with up to 280 cc of preservative-free, sterile saline. It should not be diluted with water or any other hypotonic solution that might disrupt the delivery system. The profile of adverse events for liposomal bupivacaine is that of the parent drug, bupivacaine, and the surgeon must be familiar with the adverse-event profile and treatment of bupivacainerelated adverse events.

Recent FDA approval of the liposomal bupivacaine formulation has been granted for use in hemorrhoidectomies and bunionectomies. Gorfine et al performed a multicenter, double-blind, placebo-controlled study in patients undergoing hem- The Anecdote About the Antidote: orrhoidectomies.12 The use of 300 mg of Curbside Consultations and the liposomal bupivacaine was compared Operating Room Experience with a saline placebo, and evaluated over a period of 72 hours. Pain intensity scores The use of liposomal bupivacaine has were significantly lower in the extend- been the topic of many surgical lounge dised-release (ER) group versus the place- cussions and intraoffice surgical debates. bo group. At 12 hours, 59% of patients As Exparel is expensive, much thought in the ER group were opioid-free com- has gone into the decision to purchase pared with 14% in the placebo group. and use it clinically. We have discussed At 72 hours, 28% of patients in the ER this topic with colleagues, drug represengroup were opioid-free compared with tatives and the surgeons in our group. We 10% in the placebo group. In patients decided to try liposomal bupivacaine in requiring opioids, our own, unscientific median time to trial. Our results have In the inpatient setting, first use was 14.3 been impressive. opioid-related adverse hours in the lipoOur protocol has somal bupivacaine been to adminisevents account for a group compared ter the medication in 3.3-fold increase in with 1.2 hours for the more dilute form the placebo group. using a pudendal hospital length of stay. Ultimately, a 30% block and a local infilreduction in cumutration in i the perilative pain and a 45% redu uction in anal area and around opioid consumption were seen the anal verge. in the study. The safety proTh he medicafile of the formulation haas tioon is typicalbeen studied in dose levelss lyy diluted 2:1

and infiltrated just after the surgical timeout is performed, with the patient under IV sedation. We have not experienced any anesthetic failures during the intraoperative period. At the conclusion of the procedure, a bolus of 30 mg ketorolac is given by IV route to those patients without any contraindications to its use. In the first three postoperative days, no oral or other adjunctive medications are used unless the patient feels the need for supplemental pain relief. After three days, patients are given ketorolac, 10 mg orally every six hours for 12 doses. To date, 100% of our patients have been almost pain-free for the entire six-day period. Opioid use has been minimal both during the six-day postoperative period and after the six-day period. In all of our cases, the operative anorectal procedures have been extensive. We have not used liposomal bupivacaine in procedures that we considered to be of a minor nature. Our patients have not experienced any adverse events.

The Tale of the Traveling Salesman Perhaps most interesting is one of our patients, a traveling salesman. He was due to leave town immediately after his office visit, for an important three-day sales trip. The pain from his acute thrombotic hemorrhoid had almost crippled him. Because of his impending trip, he was not amenable to surgical drainage or removal. He was desperate for pain relief and refused to consider canceling his trip. He was offered an injection of liposomal bupivacaine and he agreed to try it. The medication was diluted to 40 cc and the local injection was made through a 25-gauge needle around and deep to the thrombotic hemorrhoid. The injection of most local anesthetics in an awake patient is uncomfortable at best and the salesmanâ&#x20AC;&#x2122;s expletives attested to this. Fortunately his office visit was at the end of the day when no other patients were nearby to hear his rather loud comments during the injection. Yet, he left the office without any pain. He returned three days later in a mood bordering on euphoria. He had had no pain since the initial injection. Unfortunately for him, he lost the sale. Because he had incorrectly accounted for the time zone change during his flight, he arrived an hour late for his presentation and was denied a chance to make his pitch. This time, however, his expletives were directed at himself rather than the injection of Exparel. Surgeons cannot fix everything.

Antidote or Anecdote? Judge for Yourself We have been happy with our results to date. Patients have been happy with their results to date. But our trial is only anecdotal. Although supported by clinical trials, our results may not be the same as those of other surgeons. Time and


Clinical Review

GENERALSURGERYNEWS.COM / GENERAL SURGERY NEWS / AUGUST 2013

experience will be the final arbiter of clinical efficacy. But liposomal bupivacaine, although expensive, may be a useful medication in combating pain following anorectal operations.

13. Smoot JD, Bergese SD, Onel E, et al. The efficacy and safety of DepoFoam bupivacaine in patients undergoing bilateral, cosmetic, submuscular augmentation mammoplasty: a randomized, doubleblind, active-control study. Aesthet Surg J. 2012;32:69-76.

The authors have no financial or other relationships with any of the maufacturers of any of the drugs mentioned in this review.

14. Minkowitz HS, Onel E, Patronella CK, Smoot JD. A two-year observational study assessing the safety of DepoFoam bupivacaine after augmentation mammoplasty. Aesthet Surg JJ. 2012;32:186-193.

References

15. White PF, Schooley G, Ardeleanu M. Analgesia following a single administration of depobupivacaine intraoperatively in patients undergoing inguinal herniorraphy: preliminary dose-ranging studies. Presented at: Annual Meeting of the International Anesthesia Research Society; March 14-17, 2009; San Diego, CA.

1. Cullen KA, Hall MJ, Golosinkiy A. Ambulatory surgery in the United States, 2006. Natl Health Stat Report. 2009;11:1-25. 2. Coley KC, Williams BA, DaPos SV, et al. Retrospective evaluation of unanticipated admissions and readmissions after same day surgery and associated costs. J Clin Anesth. 2002;14:349-353.

16. Langford RM, Chappell GM, Karrasch JA. A single administration of depobupivacaine intraoperatively results in prolonged detectable plasma bupivacaine and analgesia in patients undergoing inguinal hernia repair. Presented at: 62nd Postgraduate Assembly in Anesthesiology; December 12-16, 2008; New York, NY. 17. Bramlett KW, Jones RK, Pink M, Pink T. A single administration of depobupivacaine intraoperatively provides analgesia and reduction in use of rescue opiates compared with bupivacaine HCl in patients undergoing total knee arthroplasty [poster]. Presented at the XXXVI Biennial World Congress of the International College of Surgeons; December 3-6, 2008; Vienna, Austria.

— —Dr. Hoffman is attending surgeon in the Division of Colorectal Surgery at Cedars-Sinai Medical Center, and attending surgeon in the Division of General Surgery and associate clinical professor of surgery at the David Geffen School of Medicine, University of California, Los Angeles. He is a senior member of Los Angeles Colon and Rectal Surgical Associates. Dr. Yoo is attending surgeon in the division of Colorectal Surgery at Cedars-Sinai Medical Center and associate clinical professor of surgery at the David Geffen School of Medicine, University of California, Los Angeles. He is a member of Los Angeles Colon and Rectal Surgical Associates (www.lacolon.com).

3. Warfield CA, Kahn CH. Acute pain management. Programs in U.S. hospitals and experiences and attitudes among U.S. adults. Anesthesiology. 1995;83:1090-1094. 4. Apfelbaum JL, Chen C, Mehta SS, Gan TJ. Postoperative pain experience: results from a national survey suggest postoperative pain continues to be undermanaged. Anesth Analg. 2003;97:534-540. 5. Gan TJ, Habib AS, White W, Miller T. Postoperative pain continues to be undermanaged [abstract]. Presented at: Annual Fall Pain Meeting and Workshops of the American Society of Regional Anesthesia and Pain Medicine; November 15-18, 2012; Miami Beach, FL.

36TH ANNUAL INTERNATIONAL CONGRESS OF THE EUROPEAN HERNIA SOCIETY

Edinburgh, Scotland 28 – 31 May 2014 www.ehs2014edinburgh.org

6. Oderda G, Gan T. Effect of opioid-related adverse events on outcomes in selected surgical patients. J Pain Palliat Care Pharmacother. 2012. 2013;27:62-70. 7. Pyati S, Gan TJ. Perioperative pain management. CNS Drugs. 2007;21:185-211. 8. Dauri M, Faria S, Gatti A, et al. Gabapentin and pregabalin for the acute post-operative pain management. A systematic-narrative review of the recent clinical evidences. Curr Drug Targets. 2009;10:716-733. 9. Brown SL, Morrison AE. Local anesthetic infusion pump systems adverse events reported to the Food and Drug Administration. Anesthesiology. 2004;100:1035-1037. 10. Chahar P, Cummings KC. Liposomal bupivacaine: a view of a new bupivacaine formulation. J Pain Res. 2012;5:257-264. 11. Candiotti K. Liposomal bupivacaine: an innovative nonopioid local anesthetic for the management of postsurgical pain. Pharmacotherapy. 2012;32:19S-26S. 12. Gorfine SR, Onel E, Patou G, Krivokapic ZV. Bupivacaine extended-release liposome injection for prolonged postsurgical analgesia in patients undergoing a hemorrhoidectomy: a multicenter, randomized, double-blind, placebo-controlled trial. Dis Colon Rectum. 2011;54:1552-1559.

Abstract Submission Deadline: 20th January 2014 Advance early registration fees available until 31st December 2013 Check out www.ehs2014edinburgh.org for the latest information

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LIVER RESECTION

Surgical glove port for single-port surgery.

jContinued from page 1

liver resection laparoscopically, as open, in all segments of the liver.” A new study, led by Mitsuhiro Asakuma, MD, Department of General and Gastroenterological Surgery, Osaka Medical College, Takatsuki City, Japan, demonstrated the safety and feasibility of single-port laparoscopic liver resection using a surgical glove port in 19 patients, all of whom recovered quickly and experienced minimal postoperative pain. The new research, presented at the 21st International Congress of the European Association for Endoscopic Surgery (EAES) in June, won the Olympus EAES Award for best oral presentation on single-port surgery. “I think this is a well-done study,” said Dr. Kingham, who was not involved in this research. “The surgeons’ surgical glove method, in particular, is novel and applicable in most hospitals because it does not require any extra equipment.” Other recent efforts have shown promise for a single-port approach to liver resection in selected patients. In 2011, Dr. Kingham and his colleagues published information on a small series of single-port liver resections, in which they reported the safety and feasibility of left-liver wedge resection through a single port (Surg Endoscc 2011;25:14891494). Research by surgeons in Japan showed the success of single-port laparoscopic hepatectomy in eight patients, none of whom experienced wound pain or liver dysfunction after a two-week follow-up (Surg Endoscc 2012;26:16961701). Another recent study from Korea found single-port laparoscopic liver resection to be feasible in “well-selected cases” (Surg Endoscc 2012;26:1602-1608). In this study, of the 24 patients with hepatocellular carcinoma who underwent the single-port procedure, two were converted to multiport laparoscopic hepatectomy due to limitations of the

‘The single-port technique is very limited to the superficial left sides of the liver. Our team, for instance, is focusing more on developing laparoscopic techniques that we can use anywhere in the liver, including the harder-to-reach right side.’ —Peter Kingham, MD instrument length and four were converted to open surgery. In the current prospective study, Dr. Asakuma and his colleagues completed 339 single-port surgeries from June 2009 to May 2013 at their hospital, 19 of which were single-port hepatectomies—eight partial resections, seven lateral sectionectomies, three fenestrations and one mast cell tumor. (The series also included 293 cholecystectomies, three cholecystectomies with common bile duct stones, 12 appendectomies, five colectomies and three additional operations.) Dr. Asakuma’s team performed the procedures using a surgical glove port, which they previously found was an

BREAST SURGERY jContinued from page 1 above the tumor and can significantly scar or deform the breast. Endoscopic breast surgery, developed in Japan in 1995 to reduce the number of incisions and improve cosmesis, has continued to gain popularity in Asian countries. Several endoscopic procedures have emerged, including endoscopic nipple-sparing mastectomy ((Ann Surg Oncoll 2009;16:3406-3413) and approaches that involve a periareolar incision, an axillar incision or both. VABS, for instance, requires two small incisions that can be

effective and low-cost tool to facilitate single-port surgery (World J Surg 2010;34:2487-2489). During the surgery, the team created a 2-cm incision along the umbilicus to insert the port and extract the specimens. The resection surface was a flat plane in nine cases and a curved plane in six. All but three patients had malignancies on the left side of the liver. Of the eight patients undergoing partial resection, operative time ranged from 60 to 225 minutes and bleeding occurred in one patient (800 mL). For the seven patients undergoing lateral sectionectomy, operative time ranged from 50 to 155 minutes and bleeding was minimal, also occurring in only one patient (330

hidden along the axilla and at the edge of the areola, and TARM-VABS is less invasive, reequiring only one incision in the axilla, which avoids wou unding the breast skin altogether. “Aesthetics is an important factor, and studies show endoscopic approaches are both oncologically safe and show better cosm metic results,” said Eisuke Fukuma, MD, PhD, diirector of Breast Center, Kameda Medical Ceenter, Kamogawa City, Japan, who was not involvved in the current research. In 2008, Dr. Yamashita reported the initiial success of the TARM-VABS technique on 12 patients (Chin Med J [Engl]] 2008;121:1960-1964 4), and 20

mL). No blood transfusions were needed and the resection margins remained clear. Patients resumed an oral diet and regained full mobility on postoperative day 1. The authors concluded that the single-port liver resection is an achievable technique, especially for lateral segments, and comes with several benefits to patients. “The estimated advantages of the [single-port approach] are less postoperative pain, better cosmetic results and greater patient satisfaction,” said Dr. Asakuma. “Potential disadvantages are sacrifices to safety, which we aim to eliminate.” According to Dr. Asakuma, the next step is to conduct a randomized controlled trial comparing the single-port approach to liver resection with laparoscopic and open approaches. Dr. Asakuma believes that, although single-port surgery for liver resection was born just three years ago, it has the potential to replace laparoscopic or open techniques through patient demand. However, Dr. Kingham is more skeptical of the benefits of single-port liver resection beyond cosmesis. “The single-port technique is very limited to the superficial left sides of the liver,” Dr. Kingham noted. “Our team, for instance, is focusing more on developing laparoscopic techniques that we can use anywhere in the liver, including the harder-to-reach right side.” As instrumentation improves and allows for more maneuverability, single-site liver resection may be applied to more parts of the liver, but is unlikely to become the standard of care, Dr. Kingham added. “I believe, however, that it’s important to show that single site is possible. That is how the field of surgery truly advances.” No relevant conflicts of interest were reported.


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patients ((Am J Surgg 2008;196:578-581), and, two years later, on 120 patients with early stage I and II breast cancer (Cancer Res 2010;70:P4-10-08). In all three studies, Dr. Yamashita and his colleague Kazuo Shimizu, MD, FACS, reported that although the TARM-VABS approach took 45 minutes longer than conventional VAB, all TARM-VABS patients showed negative surgical margins and better cosmetic outcomes. The TARM-VABS approach is technically feasible, but can be difficult to learn and perform, which is why Dr. Yamashita recently developed a pretumoral TARM-VABS approach to simplify the technique. “In TARM-VABS, the cutting manipulation is difficult from the backside of the mammary gland through the single axillary port.” The pretumoral approach is easier to perform because it requires later dissection behind the mammary gland, said Dr. Yamashita. In the current study, Dr. Yamashita and his colleagues performed the pretumoral TARM-VABS approach on 20 patients with early-stage breast cancer, who were aged 50.2 years, on average, and had a mean tumor size of 2.2 cm. After endoscopic sentinel lymph node biopsy, Dr. Yamashita’s team made a 2.5-cm axillary skin incision and marked the cut margins with blue dye. The surgeons dissected the subcutaneous tissue above the tumor and cut the mammary gland with clear surgical margins, removing the tumor through the axillary port using EndoCatch (Covidien). After tumor removal, they reconstructed the breast, filling the tumorless area with absorbable fiber cotton or mesh. Average follow-up time was 48 months. With the pretumoral TARM-VABS approach, all patients had negative surgical margins and no serious complications after surgery. Minor complications included small subcutaneous hemorrhage and temporary mild inflammation around the resected area of the breast. Average operative time was 127 minutes and resected volume was 24.5%. Patients also experienced high levels of satisfaction six months after the operation, rating their aesthetic outcomes an average of 13.8 of 15 total points. Despite the promising results, endoscopic breast surgery is not yet standard of care in clinical practice. “To allow this approach to

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become a standard of care, I ‘To allow this approach to become a cryoablation to treat 58 patients have to improve the manipwith breast cancer (2013 American standard of care, I have to improve the Society of Breast Surgeons annual ulating devices to perform this operation more easily manipulating devices to perform this meeting; abstract 0106). The proand introduce this surgery to cedure is safe, and no local tumor more surgeons and patients,” operation more easily and introduce this recurrence or distant metastases Dr. Yamashita said. He also surgery to more surgeons and patients.’ have occurred. is planning to perform a pro“We hope to expand this approach —Koji Yamashita, MD, PhD for larger breast tumors,” said Dr. spective study comparing the TARM-VABS approach with Fukuma. “But currently endoscopconventional breast-conservfuture of care. Cryoablation for breast ic surgeries represent good options ing surgery. cancer involves freezing and killing small and we must continue to educate doctors Dr. Fukuma believes that a nonsur- tumors (≤1 cm), using ultrasound guid- in these methods.” gical approach for treating small breast ance and local anesthesia. Since 2006, Drs. Fukuma and Yamashita reported cancers called cryoablation may be the Dr. Fukuma and colleagues have used no relevant conflicts of interest.

THE 19TH WORLD CONGRESS OF INTERNATIONAL FEDERATION FOR THE SURGERY OF OBESITY & METABOLIC DISORDERS (IFSO 2014) MONTRÉAL, QUÉBEC, CANADA • AUGUST 26-30, 2014 Montréal features modern facilities and attractions against a backdrop of European history and charm. Between Mount Royal and the might St. Lawrence River, the downtown core and historic Old Montréal shine year-round with international festivals and events. Downtown Montréal is not only where people work, it’s also where they live, play and display their unique joie de vivre. You’ll also experience a plethora of delights in music, theatre, dance, art exhibits, nightlife, cuisine, shopping and more... all merging into an exciting mix of traditional and avant-garde. Join us for presentations on cutting-edge research, world-class plenary sessions and live surgery. IFSO 2014 will be an opportunity to highlight the importance of a multidisciplinary approach to the surgical treatment of obesity and metabolic disorders.

Congress President: Dr. Michel Gagner • Phone: +1 604 688 9655 ext 2 Email: ifsoinfo@mci-group.com • Website: www.ifso2014.com


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The 24th Annual International Colorectal Disease Symposium and the 12th Annual Surgery of the Foregut Symposium All articles by Yaniv Cozacov, Clinical Fellow, Minimally Invasive and Bariatric Surgery, Cleveland Clinic Florida

Welcome to the 2013 international issue of The Surgeons’ Lounge. In this column, we bring you our coverage of the 24th Annual Jagelman/34th Annual Turnbull International Colorectal Disease Symposium and the Surgery of the Foregut Symposium, hosted by Drs. Steven Wexner and Raul Rosenthal, respectively, from Cleveland Clinic Florida in Weston. It is always our pleasure to bring you annual updates in the diagnosis and treatment of surgical diseases from the leaders in this field. Sincerely, Samuel Szomstein, MD, FACS Dr. Szomstein n is associate director, Bariatric Institute, Section of Minimally Invasive Surgery, Department of General and Vascular Surgery, Cleveland Clinic Florida, Weston.

The Watch-and-Wait Strategy for Rectal Cancer Rodrigo Perez, MD, explained the concept of the watch-and-wait strategy in regard to rectal cancer patients undergoing chemoradiation therapy (CRT) reaching complete cancer remission (clinical or radiological, not pathologic). Radical surgery has always been the mainstay of treatment for rectal cancer with appropriate total mesorectal excision. Additional therapy in the form of CRT in selected patients considered at a higher risk for local disease relapse was put in place. Postoperative radiation (adjuvant) came first and was found to improve local disease control, but at a considerably high cost in terms of toxicity and long-term complications. Preoperative radiation (neoadjuvant) improves local disease control and significantly decreases immediate and long-term toxicities. Chemotherapy, when added to the former mix, is beneficial in terms of local disease control. Furthermore, the benefits of neoadjuvant chemoradiation were not restricted to long-term local disease control, but could in actuality lead to variable degrees of tumor regression, by either primary tumor reduction in size (downsizing) or the reduction of the depth of penetration and possible

perirectal node sterilization (downstaging). With these advances, several reports have shown up to 42% complete pathologic tumor regression following neoadjuvant treatment. However, there is the question of whether these complete pathologic responses could be predicted without having radical surgery or if it is possible Baseline pretreatment

to solely rely on clinical and radiological evaluations. On one hand, complete tumor regression is assured with radical resection but on the other, it is exposing patients to a considerably morbid procedure, leading to variable rates of urinary, sexual and fecal dysfunctions. Also, the requirement for temporary or permanent stomas and the expected procedure-related mortality are substantial. Several other factors come into play considering the degree of tumor regression. Both radiation doses and chemotherapy regimens may influence the rates Tumor present at 6 weeks

of complete tumor regression. Another factor that may influence tumor regression following neoadjuvant therapy is the time lapse between completion of treatment and assessment of response. This was first suggested by data from patients with anal cancer who exhibited a significant increase in tumor response simply by waiting eight weeks after completion of therapy instead of four weeks. This is where the relatively new concept of the “watch-and-wait” strategy comes into play (Figure). Other retrospective studies have indicated that longer interval periods No tumor at 16 weeks

Figure. The watch-and-wait strategy in patients with distal rectal cancer and complete clinical response following neoadjuvant chemoradiation.


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were associated with increased rates of complete tumor regression. Therefore, the degree of tumor downstaging is time dependent, suggesting that the longer the wait, the more successful the tumor regression, and CRT seems to exert significant effects in perirectal nodes in addition to the primary tumor, as follows: • Tumors treated by neoadjuvant CRT have consistently shown decreased rates of stage III or node-positive disease. • Rates of micrometastases among perirectal nodes seem to be decreased by neoadjuvant CRT. • The observation of residual mucinous deposits among lymph nodes in the absence of cancer cells also suggests the possibility of lymph node sterilization as a result of CRT. • The overall number of recovered nodes is significantly decreased in patients after neoadjuvant therapy. This effect has also been shown to be time dependent because longer interval periods between CRT completion and surgery were associated with fewer recovered nodes. In this setting, patients with apparent complete clinical tumor regression would be ideal candidates for alternative strategies, including not undergoing immediate surgery and rigorous, close observation. But are patients being put at risk by leaving microscopic residual disease within the rectum or in perirectal nodes? Clinical assessment alone has been shown to have quite disappointing sensitivity and specificity rates in previous retrospective studies. However, some of these studies included tumor response assessment performed at six weeks from CRT completion, possibly too early, and reflecting the detection of residual disease in the setting of ongoing necrosis. Studies also have detected residual microscopic nodal disease in patients with complete pathologic primary tumor regression (ypT0). Again, these studies included patients managed by radical surgery after six weeks from CRT completion and also may reflect potential interruption of ongoing radiation-related tumor necrosis. Dr. Perez explained that the strategy is to assess tumor response at least eight weeks after CRT completion, including clinical assessment with digital rectal examination, rigid proctoscopy and carcinoembryonic antigen levels in combination with radiological assessment, mainly performed to rule out residual extraluminal disease. Only patients fulfilling these stringent criteria have been considered for this nonoperative approach (watch and wait). Patients with any small residual nodule or excisable scar are managed by a full-thickness transanal excision primarily

as a diagnostic (or eventually as a therapeutic) approach. In a retrospective analysis of patients managed by this approach, patients with complete “clinical” response did no worse than patients managed by radical surgery and complete “pathological” response in terms of survival. Late local relapses occurred in approximately 10% of patients of the watch-and-wait group, and at a considerably longer interval when compared with systemic relapses. Additionally, patients with exclusive local relapse were all amenable to salvage resection. In a retrospective review, there was

no survival compromise in patients with initial suspicion for complete “clinical” response who underwent delayed surgery for early tumor regrowth. The addition of chemotherapy cycles during the radiation therapy (RT) and the “resting” period between RT and surgery with a modest increase in RT dose (from 50.4 to 54 Gy) has led to a significant increase in complete clinical response rates to more than 50% of patients. Moreover, assessment of tumor response may further improve its accuracy with the combination of different radiological modalities such as positron

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emission tomography/computed tomography and magnetic resonance imaging brought together in a single radiological study, as well as using individualized intervals between CRT completion and the assessment of tumor response for different groups of patients. Treatment of rectal cancer has become increasingly complex and truly individualized. In this setting, a wide range of alternatives will probably offer optimal oncologic results with minimal unnecessary morbidity instead of a one-size-fitsall treatment strategy.

14th World Congress of Endoscopic Surgery Paris, France 25-28 June 2014

Hosted by the EAES and incorporating the 22nd EAES congress EAES European Association for Endoscopic Surgery IFSES International Federation of Societies of Endoscopic Surgery

HIGHLIGHTS Congress President:

Prof. Abe Fingerhut Program Committee Chair:

Prof. Nicola Di Lorenzo

r Postgraduate courses r Hands-on training r New technologies r “How I do it” video session r Pro and contra discussions r Free paper sessions: oral, video and poster r Special awards and grants r Technical exhibition

r Consensus conference on Clinical Robotics r Consensus conference on Early Rectal Cancer r Virtual live surgery r 3D video session r Management of complications r New technologies r Abdominal hernias r Keynote Lectures

The online abstract submission page will open end of September. Abstract submission deadline 15th of January 2014.

To register your interest in the congress simply return the form below to the EAES Office Fax or send it to: EAES ES O Office P.O.. Box 335 5500 AH AH,Veldhov Veldhoven The Nether Netherlandss Phone: +31(0)40 252 5288 Fax: +31(0) 40 252 3102 E-mail: congress@eaes.eu Internet: er www.e w.eaees.eu eu

Last Name First Name Address City + ZIP Code Country Phone

Fax

E-mail

Reply Card to obtain membership applications Name Address City + ZIP Code

EAES Membership If you are interested to become an EAES Member, please complete and return this reply card. E-mail: membership@eaes.eu

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Resident in Training


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Mental Conditioning in Surgical Education In his presentation, Raul Rosenthal, MD, department chair, Bariatric and Metabolic Institute at Cleveland Clinic Florida, Weston, discussed mental conditioning, or mental training in surgical education—a concept derived from the worlds of sports and aviation. The goal of mental training is to enhance performance and achieve maximal dexterity and preparedness during action time. This allows for speed response, meaning “simply being good when it counts” (Figure 1). Athletes execute complex muscle movements— which involve several motion sequences—requiring high levels of deftness and cognitive function. Additionally, they must perform at the highest level with minimal time to react and cognitively process their responses under stressful conditions. For athletes,

Figure 1. The goal of mental training.

mental training works by optimizing their movements and reducing cognitive interference. The way in which athletes undergo mental training is by systematically repeating a movement in their imagination, without actually performing it. The way a complex movement, or a series of motions, are mentally processed, is first to be broken down into the mainstay of nodal points (Figure 2). For example, if a soccer player is to kick a ball, he or she would first break down the sequence into selecting the target, selecting which foot to kick with, approaching the ball and then kicking it. In the same way, when applied to surgery, a procedure is to be described in detail, the nodal points extracted, and then the trainee can imagine each mental point separately until the whole procedure is mentally processed. In aviation, the nodal points exist in the form of a checklist. In normal and abnormal situations, the pilots are going through processes for takeoff and landing. It has been shown that pilots who regularly undergo a series of simulated training enhance their proficiency under stress and are able to master abnormal situations.

Laparoscopic Approaches to Gastrointestinal Stromal Tumors

Laparoscopic Approaches to Gastrointestinal Stromal Tumorsa Submucosal Tumor

Sung-Soo Park, MD, associate professor at Korea University College of Medicine, in Seoul, discussed how to determine the optimal laparoscopic approach when performing a wedge resection of gastric submucosal tumors. Dr. Park presented his experience with almost 60 patients, of whom twothirds underwent an exogastric wedge resection (EWR) and the remaining one-third underwent a transgastric wedge resection (TWR) for gastric submucosal tumors (J Am Coll Surg 2012;215:831-840). His team compared the clinical outcomes for both EWR and TWR approaches, and Dr. Park provided an analysis of the factors affecting selection. In most cases, the diagnosis of gastric submucosal tumors was incidental and approximately 80% turned out to be gastrointestinal stromal tumors (GISTs). Preoperative assessment of the degree of potential malignancy was insufficient, and complete surgical resection was needed for

comprehensive diagnosis and prognostic evaluation. As a result, positive margin–free wedge resection of submucosal tumors was the standard of care. Dr. Park reported that EWR was safe and effective, and simple to perform, and required a short operative time. Although TWR allowed direct visualization of the lesion via gastrostomy (thus providing better control of the surgical margins), the gastrostomy procedure itself may pose a risk for intraperitoneal cross-contamination with gastric flora. Furthermore, the need for gastric wall closure prolongs the operating time. Of the two approaches, surgeons use EWR more frequently. The major factors to consider when

This proficiency declines over time, so pilots need to train regularly to retain it. Aviation safety is measured by accidents per 1 million flights. The number of fatal accidents is more than three per 1 million when the aviation company does not appropriately select their pilots, does not have internal training for pilots, has no homogeneity of staff and does not conduct training on simulators. However, when all of these factors are implemented, the number of fatalities drops to 0.2 per million, an important distinction when one considers that approximately 10 million flights are made in the United States every year. So how can mental training be used in surgery? It can reduce the stress potentials by optimizing movement and operating room performance. Mental training is performed in four different training sessions: 1. External observation training: The trainee observes a role model performing the movement that the trainee wishes to learn. 2. Subvocal training: The trainee conjures up a clear visual image of the movement through external or internal self-talk. 3. Internal observation training: The trainee visualizes himself or herself, or another person from the outer perspective performing the movement he or she wants to practice. 4. Ideomotoric training: The trainee imagines the movement from the inner perspective, visualizing the execution of the movement and trying to feel as many sensory aspects of the process as possible. Ideomotoric training relies on the fact that,

Size

Location

Growth pattern

Appropriate operation

≤2.5 cm

High or low in HA

Endophytic growth

Transgastric wedge resection

Exogastric wedge resection

Figure. The therapeutic strategy for submucosal tumors of the stomach. Red arrows indicate positive results, and gray arrows indicate negative results. a

Surgical approach for endomural growth pattern depends on the surgeon’s preference.

HA, hidden areas


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the core of mental training, where complex movements in both cases are recorded by the brain and retained as muscle memory. Roth et al showed this using a functional MRI imaging study to record both actual and ideomotoric movements. Dr. Rosenthal summarized the following: • Additional mental training is effective. • Mental training can be learned easily by surgeons in two hours. • Cognitive rehearsal is cheaper than practical training. Figure 2. Complex movement is broken down into the mainstay of nodal points. regardless of whether a person actually performs a muscular movement or imagines himself or herself doing so, the brain will register it the same. For example, if a person lies still and moves an index finger, under functional magnetic resonance imaging (MRI) the frontal cortex would enhance (the frontal cortex is responsible for planning of the movement) and the motor cortex in the region innervating the index finger also would enhance. In the same manner, if a person were to lie still but only imagine moving his or her index finger, the brain will enhance in the same pattern as if the finger was moving. This is

choosing between TWR and EWR include tumor size, location and growth pattern, Dr. Park said (Figure). Regarding tumor size, EWR should be performed if the tumor is greater than 2.5 cm, regardless of the other factors, because with a larger tumor it is easier for the surgeon to locate it by simple manipulation. For tumors smaller than 2.5 cm, EWR should be performed in all tumor locations except for the upper or lower thirds of the stomach; near the esophagogastric junction; the pylorus; or in hidden areas such as the posterior wall and lesser curvature of the circular location of the stomach, which have both a relatively narrow field of vision and limited space for manipulation. EWR should be performed for tumors with an exophytic growth pattern, and TWR should be carried out for tumors with an endophytic growth pattern. The surgical approach for tumors with an endomural growth pattern depends on the surgeon’s preference, Dr. Park said.

• Once a surgeon has the necessary skills, he or she can carry out mental training on his or her own. • Mental training can be transferred easily to other procedures. • Mental training cannot replace practical training. • Mental and practical training should be combined, as it occurs in sports, and should be viewed as a relevant and valuable part of surgical training.

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Laparoscopic Ventral Rectopexy for Rectal Prolapse Syndromes Professor Andre D’Hoore, MD, discussed his experience at the University Hospital Gasthuisberg in Leuven, Belgium, for the treatment of rectal prolapse syndromes using the laparoscopic approach for ventral rectopexy. External or internal rectal prolapse and rectocele are the most difficult clinical problems in colorectal surgery. Symptoms vary from obstructive defecation to fecal incontinence, resulting from chronic sphincter damage. Several surgical procedures have been developed in an attempt to restore these conditions. To date, the surgical community has not yet accepted a standard method, although abdominal rectopexy is considered superior to perineal or transanal approaches because of lower recurrence rates and better functional outcomes. However, the induction or worsening of postoperative constipation was observed as the most common side effect of rectopexy. An inherent step in classic rectopexy is the full mobilization of the rectum. Autonomic nerve injury during extensive posterolateral rectosigmoid mobilization may lead to postoperative dysmotility and impaired evacuation. In contrast, transanal partial rectal resection or plication may induce or worsen incontinence. Laparoscopic ventral rectopexy (LVR) using a polypropylene mesh has been introduced to combine the good functional outcome of the abdominal procedure while avoiding both postoperative constipation and incontinence. In a study between January 1999 and December 2008, 405 patients underwent LVR for rectal prolapse syndromes. The median age of participants was 55 years (range, 16-88) and 93% of patients were women. More than 41% (n=168) had undergone previous pelvic surgery, of which 39% were hysterectomies. In 27 patients (6.7%), LVR was performed for recurrent rectal prolapse. Data concerning operative difficulties and conversion, postoperative morbidity, and recurrence were gathered from a prospective database. The mean follow-up was 25 months (range, 6-143). An extensive, institutional questionnaire that assessed symptoms of anorectal and sexual dysfunction was used. Nearly half of the patients suffered from internal rectal prolapse (45.9%; n=186). Other indications were total rectal prolapse (43%; n=174) and isolated rectocele and/or enterocele (11.1%; n=45). In 95 patients (23.5%), laparoscopic dissection of the rectovaginal septum was completed with a small perineotomy to treat a complex supra-anal rectocele.

Surgical Technique Limited bowel preparation and a single dose of a broad-spectrum antibiotic, as well as thrombophylaxis, were given preoperatively to the patient. The “bean bag” allows steep Trendelenburg in the operating room: A modified lithotomy position with both arms tucked was used. A bladder catheter was inserted, the vagina disinfected, and the camera port was introduced at the umbilicus. Three additional ports were inserted into the right flank (5 mm), the left iliac fossa (5 mm) and the right lower quadrant (12 mm). A 30-degree optic was used and temporary hysteropexy enhanced the pelvic view. The entire small bowel was retracted out of the pelvis. Next, the mesosigmoid was retracted to the left and a peritoneal incision was made over the sacral promontory and caudally extended along the rectum and over the deepest part of the pouch of Douglas (special care was taken to preserve the right hypogastric nerve). The sacral promontory needed to be sufficiently dissected to allow safe mesh fixation (too medial a

Figure 2. The deepest part of the fold of Douglas is retracted and incised. The rectovaginal septum is opened without any lateral dissection.

Figure 1. Dissection starts at the sacral promontory with preservation of the right hypogastric nerve. The caudal extension of the peritoneal incision follows the dotted line.

dissection must be avoided to safeguard the left iliac vein) (Figure 1). The rectovaginal septum was opened after a firm retraction of the deepest part of the fold of Douglas. The Denonvilliers fascia was incised, and the anterior aspect of the rectum was dissected, leaving all fibrous tissue against the posterior vaginal wall (Figure 2). A Marlex mesh (approximately 3×17 cm) was sutured to the ventral aspect of the distal rectum using nonabsorbable sutures to inhibit further rectal intussusception. Extracorporeal suturing seemed the most appropriate in the deepest part. Care was taken to ensure that the mesh lay flat on the rectum to avoid any mechanical erosion due to mesh kinking. The mesh was then fixed to the sacral promontory using an endoscopic "tacker" device, and secured with one stitch of ethibond 2.0. No traction was exerted on the rectum, which remained in the sacrococcygeal hollow (Figure 3). The posterior vaginal apex (vaginal vault) was then elevated and sutured to the same strip of mesh (Figure 4). Two lateral sutures incorporated the remainder of the uterosacral ligament. More suturing may be needed depending on the degree of middle compartment prolapse. Ideally, the sutures should not perforate the vaginal wall. The mesh could be left broader at that site to allow adequate vault suspension. The lateral borders were closed over the mesh using the V-Loc 90 absorbable wound-closure device elevating the neo-Douglas over the colpopexy. This maneuver was important to avoid any later small bowel entrapment and/or erosion. It can be difficult to complete the rectovaginal septum dissection to the pelvic floor level. In treating a complex rectocele, the surgeon may decide to complete the laparoscopic dissection with a small perineotomy. The incision is made immediately dorsal to the vaginal orifice to open the

Figure 3. A strip of polypropylene is sutured to the anterior aspect of the rectum and fixed without traction on the sacral promontory.

Figure 4. The posterior vaginal wall is elevated and sutured to the same mesh.


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High-Grade Dysplasia: Esophagectomy or Endoscopic Therapy? Thomas Rice, MD, section head, Department of Thoracic and Cardiovascular Surgery, Cleveland Clinic, Ohio, compares esophagectomy with endoscopic therapy as a treatment modality for esophageal high-grade dysplasia.

Freedom From Recurrence (%)

perineal body and dissected to join the laparoscopic dissection plane, allowing mesh fixation in the deepest part of the rectovaginal septum and restoring the perineal body. The perineotomy, however, could be avoided in most patients with a total rectal prolapse. Postoperatively, no drain is needed in most cases, and the patient can be discharged from day 1 onward.

Outcome After Laparoscopic Ventral Rectocolpopexy Conversion to laparotomy was required in eight patients (2%). The mean hospital length of stay (LOS) was 5.1 days and the last 50 patients had an LOS of 3.2 days. Perioperative mortality did not occur. Minor morbidity was noted in 74 patients (18%); urinary tract infection in 23 (5.9%); superficial wound dehiscence in 18 (4.6%); prolonged ileus in12 (3.1%); and

postoperative hematoma or bleeding in nine (2.3%). Six patients (1.5%) underwent a re-intervention under general anesthesia within 30 days of surgery. Ten patients (2.5%) developed dyspareunia. Prolonged neuralgia (six weeks) at the right lower quadrant port was documented in six patients (1.5%). Five patients (1.3%) were seen with mesh erosion. All of the patients underwent a combined approach with perineotomy for a grade III supra-anal rectocele. Five patients (1.3%) had a trocar-site hernia. No major septic complications were observed. Clinical recurrence was noted in 4.6% of 174 patients after LVR for total rectal prolapse. Only four of these eight patients underwent further perineal surgery. Recurrence for internal rectal prolapse was lower (0.5%), but the need for perineal surgery during follow-up was higher (4.3%). Failure of the mesh fixation onto the

Recurrence (%/year)

The introduction of less-invasive techniques Although overall survival rates are generally simiinto the therapeutic armamentarium of intramu- lar for esophagectomy and endoscopic therapy, cancosal lesions has brought into question the use of cer-free survival is found to be worse after endoscopic esophagectomy, an invasive procedure for esopha- therapy. Recurrence of cancer after esophagectomy is geal high-grade dysplasia. Dr. Rice discussed the uncommon, and typically occurs soon after surgery, experience of patients at the Cleveland Clinic that whereas recurrence after ablative therapy occurs later included 164 patients treated with esophagectomy and is a continuous problem. A five-year, cancer-free over a span of almost 30 years (Eur J Cardiothorac survival rate of 97% is achievable after esophagectoSurg 2011;40:113-119). my, but the rate is only 80% after endoscopic therapy. His team reported excellent outcomes with esophagectomy. Although there is a risk for mortality in the early stages 100 4 after the procedure, that risk subsequentFreedom From Recurrence ly declines to similar levels for the general 80 population. Patient characteristics associ3 ated with early mortality include patients of older age at the time of esophagecto60 my and poor lung function associated with respiratory complications, particular2 Hazard ly pneumonia. In terms of late mortality, 40 cancer recurrence and second non-esophageal cancers were found to be risk factors. 1 20 Dr. Rice noted that approximately half of the patients experience a complication after esophagectomy, whereas treatmentassociated mortality is rarely reported after 0 5 10 15 Years endoscopic therapy and risk for complications is approximately less than 50% comFigure. Recurrence rates after esophagectomy. pared with esophagectomy.

Once patients cross the threshold of expected early recurrence (approximately two to three years), recurrence is rare: In Dr. Rice’s study, the last recurrence was reported at 37 months (Figure). Dr. Rice said that although esophagectomy is more successful and effective in this setting compared with endoscopic therapies, it is not as safe. Treatment decisions require balancing the possibility of patient harm with ineffective cancer treatment, so a comprehensive patient selection process is crucial. Esophagectomy as a treatment modality should be assigned to patients in whom complete and durable eradication of the cancer is paramount, and who also are at low risk for any procedure-related morbidity. When the risk associated with esophagectomy outweighs the benefits, endoscopic therapy should be considered. In reality, a risk–benefit analysis is usually poorly performed, as the main determinant of which therapy the patient will undergo largely depends on who performed the first evaluation: the surgeon or the gastroenterologist. Dr. Rice concluded that in high-grade dysplasia in older patients with poor pulmonary function, endoscopic therapy is favorable. However, in young patients with excellent pulmonary function, the decision becomes more difficult, and all the benefits of cancer-free survival, weighed against morbidity, should be discussed with the patient.

sacral promontory was noted in four patients during re-laparoscopy. In one patient, dehiscence of the rectal fixation was seen, and in another, incomplete reduction of the prolapse at the time of mesh fixation evidently resulted in a persistent prolapse. Significant improvement in symptoms was reported in 85.6% of patients at final follow-up. Obstructed defecation resolved completely in 71.1%, whereas new-onset constipation was documented in only 10 patients (2.3%). Fecal incontinence improved in 84.5% of patients. Obstructed defecation, which was present in 120 patients with internal rectal prolapse before LVR, had resolved in 59.2%. Constipation was induced in 3%. Fecal incontinence improved in 88.9% of patients with internal rectal prolapse, and at final follow-up, 70.4% of patients reported improvement of functional outcome.

In summary, Professor D’Hoore noted that surgical treatment of rectal prolapse syndromes remains controversial in colorectal surgery. A large number of operations are described in the literature. LVR was developed in an attempt to fulfill the three main objectives of prolapse surgery: restoration of the anatomy in a reliable, safe and reproducible way; improvement of anorectal function; and avoidance of functional sequelae (constipation and incontinence). After LVR for total rectal prolapse, a significant improvement occurred in 85% of patients at final follow-up. Potential functional problems should be investigated before LVR in patients with internal rectal prolapse. Moreover, mechanical and functional obstruction may coexist. LVR, with or without perineotomy, was found to be safe with relatively low morbidity and functional outcomes supported its efficacy. The indication for LVR in patients with internal rectal prolapse should be optimized.

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A Valuable Alternative to Biologics f or complex sof t tissue reinf orcement.

Finally – an alternative to biologics! GORE® BIO-A® Tissue Reinforcement is a unique non-biologic scaffold that is gradually absorbed by the body. The open, highly interconnected 3D pore structure facilitates cell infi filtration and growth. Vascularization begins quickly within one to two weeks. • 100% synthetic, bioabsorbable tissue scaffold • Rapid cell population and vascularization • Versatile for numerous applications • Available in large sizes up to 20 cm x 30 cm With a three-year shelf life and no soaking, refrigeration or tracking required, this versatile material is the easy-to-use, performance-proven alternative that offers value for surgeons and hospitals. Gore. Because material really does matter.

W. L. Gore & Associates, Inc. • Flagstaff, AZ 86004 • goremedical.com Products listed may not be available in all markets. GORE®, BIO-A®, PERFORMANCE THROUGH INNOVATION, and designs are trademarks of W. L. Gore & Associates. ©2013 W. L. Gore & Associates, Inc. AS1948-EN1 JUNE 2013


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SEPTEMBER 2013 RP1606

REPORT Clinical Performance and Economic Analysis of GORE速 BIO-A速 Tissue Reinforcement Faculty

James J. Chao, MD, FACS Director of Plastic Surgery, OasisMD Clinical Professor, Plastic and Reconstructive Surgery University of California, San Diego School of Medicine San Diego, California

B. Todd Heniford, MD, FACS Professor of Surgery Chief, Division of Gastrointestinal and Minimally Invasive Surgery Director, Carolinas Hernia Center Co-Director, Carolinas Laparoscopic and Advanced Surgery Program University of North Carolina at Chapel Hill Charlotte, North Carolina

Garth Jacobsen, MD, FACS

Brent Matthews, MD, FACS

Program Director, General Surgery Director, Hernia Center University of California, San Diego Department of Surgery San Diego, California

Chief, Minimally Invasive Surgery Co-Director, MIS Institute Professor of Surgery Washington University School of Medicine St. Louis, Missouri

Supported by


REPORT

he development of synthetic, biosynthetic, and biologic surgical meshes to provide reliable tissue reinforcement has been driven in part by the high rate of recurrent incisional hernias after laparotomy.1 Use of surgical meshes has reduced recurrence rates overall which has led to their widespread use,2 although no one type of mesh has been proven to be beneficial for all patients or procedure types. Risk for infection, adhesions, and fistulas can be high for synthetic meshes,3 particularly when used in contaminated surgical fields.4 Switching to a biologic mesh has been shown to reduce these risks versus no mesh use5 while ensuring a lowered rate of hernia recurrence,6 but are offered at a significantly higher cost than other mesh types.7 The third option for hernia repair, biosynthetic mesh, was first introduced by W. L. Gore & Associates, Inc. in 2008 as GORE® BIO-A® Tissue Reinforcement (Figure 1).8 Composed of a bioabsorbable material which has years of positive outcomes data supporting its use,9 GORE® BIO-A® Tissue Reinforcement has been developed to provide clinical results at

T

Figure 1. GORE® BIO-A® Tissue Reinforcement. Image courtesy of W. L. Gore & Associates, Inc.

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considerable economic value over biologic meshes, making it a preferable choice for soft tissue reconstruction. This report will present an analysis of the available clinical performance, scientific, and economic data in the literature along with a discussion by faculty with experience in using various mesh types, including GORE® BIO-A® Tissue Reinforcement.

Background—Clinical Need The use and study of surgical mesh has been concentrated in repair of midline abdominal incisions primarily because this is the area of greatest clinical need. Thus, tissue reinforcement material capable of reducing incisional hernia risk or hernia recurrence has great implications not only for circumventing the risks for reoperation, but also for circumventing the risk for long-term complications, including an adverse effect on such quality-of-life measurements as pain, discomfort, and the ability to perform normal activities of daily living.10 “The clinical need for tissue reinforcement in repairs of the abdominal wall is apparent in persistently high recurrence rates independent of surgical technique or where the surgery is performed,” said Garth Jacobsen, MD, FACS, program director of general surgery and director of the Hernia Center at the University of California, San Diego Department of Surgery in San Diego. To reduce recurrence rates, “there is no practical alternative to some form of tissue reinforcement for large defects or in patients who have had previous recurrent hernias,” he said. In the formation of tissue reinforcement, there has been an intensive effort to identify materials that reduce the risk for recurrence without introducing a new set of hazards. At most recent count, there are more than 200 surgical meshes commercially available in the United States.11 These products generally can be divided into 3 major categories: biologic, biosynthetic, and synthetic. These product types differ fundamentally in character. Biologic prostheses employ human cadaver or animal tissue processed to provide a scaffold for repopulation by host cells.12 Biosynthetic prostheses employ biodegradable polymers for the same goal.13 Synthetic prostheses, unlike those formed with biologic or biosynthetic material, are not designed only to induce autologous cell repair or be resorbed, but remain as a permanent fixation device. “Synthetic prostheses can be engineered for strength, but there are numerous short- and long-term complications associated with foreign bodies,” explained Brent Matthews, MD, FACS, professor of surgery, chief of the Section of Minimally Invasive Surgery (MIS), and co-director of the MIS Institute at Washington University School of Medicine in St. Louis, Missouri. “Whether with biologics or biosynthetics, the concept of providing a scaffold on which native cells can repopulate to


REPORT

increase strength in tissue underlying the repair, but without any permanent foreign body, is attractive.” As previously mentioned, the limitations of nonbiodegradable synthetic mesh have been greatest in clean-contaminated or contaminated surgical fields where they impose a high risk for late infection, foreign-body reactions, fistula formations, and adhesions.4,14 These risks have persisted across an array of nonbiodegradable materials, such as polypropylene, multifilament polyester mesh, and polytetrafluoroethylene.15

Mesh Alternative: Bioabsorbable GORE® BIO-A® Tissue Reinforcement The first products of biodegradable mesh were composed of human or animal tissue. Examples of biologics in current use include those derived from human cadaver dermis, decellularized porcine small intestinal submucosa, and decellularized crosslinked porcine dermis. These varieties also differ in how they are processed and treated, which can affect their performance and risk for adverse events, such as potential inflammation or foreign body reaction, which can alter the speed of cellular infiltration. As an alternative to biologics, GORE® BIO-A® Tissue Reinforcement was introduced to build on one of the key advantages of biologics, which is resorption. Biosynthetic meshes are designed to provide a matrix or scaffolding for ingrowth of native tissue that will potentially reduce hernia recurrence.12

A

Consequently, the eventual absorption of exogenous material after healing aims to avoid the long-term complications of an indwelling foreign body. Furthermore, a bioabsorbable prosthesis like GORE® BIO-A® Tissue Reinforcement can be offered at a lower cost and possesses characteristics that have the potential to lower the risk for reherniation without the associated cleansing processes used by biologic manufacturers to remove any potential viruses or contaminants from the cellular structure.16 Plus, as a biosynthetic product, GORE® BIO-A® Tissue Reinforcement does not require the tracking, storage, and preparation procedures required by biologics.

Supporting Evidence on the Use of Biosynthetic Mesh Although biosynthetic meshes have emerged as a less costly and potentially similarly effective alternative to biologic meshes, the absence of level 1 data that establish a relative benefit of biologics over synthetic meshes means that there is no clear standard against which to compare biologics with each other or biosynthetic devices with biologics. Recent animal data have compared the efficacy of a biosynthetic mesh to a biologic mesh and shown an increase in cellular and vascular ingrowth and collagen deposition when examining implanted GORE® BIO-A® Tissue Reinforcement against a biologic mesh at up to 180 days (Figures 2-4).17

B

Figure 2. H&E stain showing tissue ingrowth at 30 days for (A) GORE® BIO-A® Tissue Reinforcement and (B) FLEXHD ® Mesh (Ethicon) for comparison.17

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“There is a general consensus that a biodegradable mesh is preferable to permanent synthetic mesh in clean-contaminated and contaminated surgical fields because of the evidence that the risk for infection is lower, but there have been very few data with which to evaluate the relative efficacy of biologics and biosynthetics,” said B. Todd Heniford, MD, FACS, chief of the Division of Gastrointestinal and Minimally Invasive Surgery at Carolinas Medical Center in Charlotte, North Carolina. “We are now collecting the data to resolve these questions. Other than the difference in infection rates derived from noncomparative studies, the movement toward using biologic meshes in contaminated fields has been based more on theory than on actual comparative data.” The theory is well supported by the high risk for adhesions and fistulas associated with permanent synthetic mesh placed in contaminated wounds.3 The ability of biologics to lower or circumvent these risks is based on promising evidence 5 ; resorption may take place before these complications develop. Resorption of biosynthetics would be expected to deliver a comparable benefit. However, controlled multicenter studies to specify where different types of surgical meshes perform best have never been conducted. “There are a lot of data from single-center case series, but it is difficult to draw strong conclusions about the relative performance of one mesh over another when so many variables,

A

including the patient mix and the surgeon’s skill, may affect outcome,” noted James Chao, MD, FACS, professor of Plastic and Reconstructive Surgery in the Department of Plastic Surgery at the University of California, San Diego School of Medicine in San Diego. “Ideally, the scaffolding allows remodeling in which native tissue is restored to prevent weakness at the site of abdominal repair, but performance has been difficult to judge objectively from case series alone because biologics are more likely to be used in contaminated fields where the risk for complication is greater,” Dr. Chao added. A multicenter, prospective, single-arm trial, the Repair of Infected or Contaminated Hernias (RICH) study investigated the use of a non-crosslinked, porcine acellular dermal matrix for ventral hernia repair in a contaminated setting. Researchers found that after 2 years, greater than 70% of patients had experienced a successful mesh repair; 22 out of 80 patients had hernia recurrences (28%), and presence of infection was seen in 24 patients.18 A growing body of experimental and clinical data generated from studies conducted with currently marketed biologic mesh prostheses also exists; however, data contrasting product types and conflicting data within each type often leave clinicians with choices based on their own interpretation of relative advantages and disadvantages of different kinds of mesh. “In patients at low risk for infection and clean surgical

B

Figure 3. Hirovici stain showing new collagen deposition (blue) at 30 days for (A) GORE® BIO-A® Tissue Reinforcement and (B) FLEXHD ® Mesh (Ethicon) for comparison.17

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REPORT

fields who need a mesh, we are still likely to employ a permanent synthetic because of the lower cost. In patients with clean-contaminated or contaminated wounds, choice between a biosynthetic and a biologic is less clear. At our center, we reserve biologics for patients with a contaminated surgical field, but the supportive data are circumstantial,” Dr. Heniford said. “There is a large advantage in cost with a biosynthetic relative to a biologic, so data that allow us to understand the relative performance has the potential to change our practice.”

Data on GORE® BIO-A® Tissue Reinforcement— The COBRA Study Data are now being collected prospectively in one of the largest and most comprehensive clinical studies undertaken with any bioabsorbable mesh, whether a biologic or a biosynthetic. The prospective study, called COBRA (Complex Open Bioabsorbable Reconstruction of the Abdominal Wall), began enrolling patients at 9 participating centers in the United States and Europe in March 2011.19 Eligibility requirements included a hernia defect of at least 9 cm2 and a clean-contaminated or contaminated operative field.19 In preliminary data of 104 patients, the majority of

patients (77%) treated had a contaminated field and more than one-third of patients (42%) had a previously implanted mesh. Over one-fourth (27%) were undergoing removal of infected mesh.19 A standardized laparotomy technique with retrorectus or intraperitoneal placement of the mesh and fascial closure is being employed. Outside of infected mesh removal, the most common reasons for concomitant procedures were bowel resection (28%) and reversal of ostomy (22%).19 Whereas final results will be presented when 2 years of followup are available for all enrollees, preliminary findings presented at several scientific meetings, including the 2013 American Hernia Society (AHS)19 and the 2012 American College of Surgery (ACS) meeting,20 are promising. Early results indicate a low rate (4%) of hernia recurrence at 210-day mean follow-up.19 Other events, such as wound infections, seroma formation, and bowel obstruction, also are being monitored and will be evaluated in the final report. So far, surgical site infections were observed in 18% of patients, with no removals of infected bioabsorbable material required, and wound complications, other than infection, have occurred in less than 5% of cases.19 “Findings from COBRA will provide objective data on performance. When the results become available, we will no longer be debating the theoretical advantages of specific design

GORE® BIO-A® Tissue Reinforcement

Grade

6 5

FLEXHD® Mesh (Ethicon)

4

STRATTICE Mesh (LifeCell)

3

PERMACOL Mesh (Covidien)

2 1 0 7

14

30

60

Days

90

180

Grade Total Ingrowth (% mesh thickness) 1 0-20% 2 20-40% 3 40-60% 4 60-80% 5 80-100%

Figure 4. Total cellular ingrowth.17

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characteristics but will have actual data. I am not aware of an equivalent multicenter study being performed with any other mesh,” Dr. Matthews said. “We need this kind of data for evidence-based practice.” When completed, the COBRA study will provide one of the most comprehensive evaluations of any surgical mesh, and it will be particularly useful for clarifying the efficacy of GORE® BIO-A® Tissue Reinforcement in both clean-contaminated and contaminated wounds. Also, this study has been designed to collect relevant information on a broad range of preoperative and perioperative variables, including baseline comorbidities, such as diabetes mellitus, inflammatory bowel disease, or obesity, as well as procedure time.19 These may permit meaningful stratifications at the final data analysis.

Biosynthetic Engineering: GORE® BIO-A® Tissue Reinforcement The single most important feature of biologics, particularly relative to tissue reinforcement with synthetic material, is resorption. Elimination of the mesh avoids many of the long-term complications associated with indwelling exogenous material. Biosynthetic mesh shares this important feature but has the potential to offer greater efficacy at a lower cost. Human and animal tissues from which biologic meshes

Figure 5. Large and interconnected pores of GORE® BIO-A® Tissue Reinforcement (100x magnification). Image courtesy of W. L. Gore & Associates, Inc.

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are processed do not necessarily offer the optimal characteristics for ingrowth of native tissue. Engineering of biosynthetic materials has the potential to deliver characteristics that biologics are unable to provide, including more consistency, mesh sheets in larger sizes, and the opportunity to alter material composition to improve dynamics, such as stretch, that may facilitate handling. Biosynthetics avoid the costs of acquiring, sterilizing, and processing human or animal tissue, which is an explanation for the high costs of biologics.

Material Characteristics GORE® BIO-A® Tissue Reinforcement is produced from a co-polymer of polyglycolic acid and trimethylene carbonate (PGA:TMC),16 for which extensive clinical experience in bioabsorbable sutures and staple line reinforcement already existed before the construction of a surgical mesh. The favorable safety, tolerability, and absorption characteristics of absorbable staple line reinforcement produced with PGA:TMC have been published in a broad range of applications including bariatric,9 colorectal,21 and abdominal surgery.22 In the construction of surgical mesh with PGA:TMC, a 3-dimensional matrix has been engineered to provide open, interconnected pores (Figure 5) with biocompatible fibers that allow pore size to be optimized for ingrowth.16 In experimental studies, the ability to manipulate such characteristics as pore size of the polymer fibers has been shown to alter the rate and degree to which native tissue is incorporated into the scaffolding as well as the rate at which the prosthesis is bioabsorbed.23,24 Both results may have implications for the speed and quality of the wound repair and relative protection against reherniation as well as infection or complication risk. The value of the specific features of any structural characteristic ultimately is demonstrated in long-term clinical performance, but theoretical advantages can be derived from experimental studies. In a 1-year comparison of 5 different surgical mesh types with different characteristics, the outcomes were revealing. Conducted in rabbits with large (11×4 cm) abdominal wall defects, the study included a crosslinked biologic mesh (PERMACOL Mesh, Covidien), a non-crosslinked biologic mesh (SURGISIS Mesh 4-ply, Cook), a matrix biodegradable mesh employing 2 fibers purported to provide fast and slow absorption (TIGR® Mesh, Novus), a polypropylene synthetic mesh (BARD Mesh, Davol), and GORE® BIO-A® Tissue Reinforcement.24 The only small recurrent hernias occurred in the non-crosslinked biologic. TIGR ® Mesh had a higher rate of foreign-body reaction and adhesion formation similar to the polypropylene mesh. GORE ® BIO-A® Tissue Reinforcement provided the optimal tissue remodeling and was completely resorbed.24


REPORT

“When we compare biologic to biosynthetic, it is imperative to remember that the products within these categories vary substantially,” Dr. Matthews noted. “These products have not been interchangeable. Often, it is a question of a balance, such as strength versus pliability versus resorption profile. The best product for one patient may not be the best for another.”

Rapid Cellular Infiltration and Vascularization The specifications of the mesh, including the composition of PGA to TMC (67% and 33%, respectively), the pore size, and the structure were all selected on the basis of bioengineering and tests performed in experimental modeling. The goal is to sustain a matrix long enough for new tissue to build but without risk of permanent material present. Experimental studies support a defined mechanism with a predictable rate of resorption. “We know from experimental data that pore size does matter,” Dr. Chao said. “Pore size that is too small will yield less ingrowth with suboptimal tissue characteristics. Although we may look for different physical characteristics from a biosynthetic mesh for different repairs, such as relative strength or pliability, there has been some progress in understanding what features are likely to affect outcome.” In an ex vivo histologic evaluation of tissue in an animal model of abdominal repair conducted 1, 3, and 6 months after placement of GORE® BIO-A® Tissue Reinforcement, tissue specimens demonstrated enhanced fibroproliferation, gelatinolytic activity, and angiogenesis when compared with suture-only repairs.25 The prosthesis was still discernible by 3 months, but was nearly fully degraded by 6 months, at which time the tensile strength was greater at the wound site among animals receiving the prosthesis compared with those that did not.25 “The science over the past 10 years has advanced markedly. Experimental evidence has been important for identifying the characteristics that influence collagen deposition, rate of bioabsorption, and other features that we would expect to improve protection against recurrent hernias while reducing risk for long-term complications,” Dr. Heniford said. “Understanding these characteristics has been important for a rational approach to mesh design.”

GORE® BIO-A® Tissue Reinforcement Performance Versus Biologics Relative to biologics, which are constrained by the characteristics of the underlying tissue—whether human or animal origin—biosynthetics have the potential to be engineered not only to optimize growth, but also to offer favorable handling characteristics. Unlike biologic surgical mesh, which only can

be produced in limited sheet sizes and typically requires preoperative soaking, GORE® BIO-A® Tissue Reinforcement comes in sizes as large as 20×30 cm and does not require soaking or tissue tracking.16 GORE® BIO-A® Tissue Reinforcement also is easy to manipulate in both open and endoscopic procedures even relative to other biosynthetics. “From a practical perspective, GORE® BIO-A® Tissue Reinforcement is easy to use. It holds sutures well; it can be cut for fit; and it is easy to grasp and handle for positioning,” Dr. Chao said. “There are differences in the features of biosynthetic products. GORE® BIO-A® Tissue Reinforcement is somewhat thicker than some alternative biosynthetics. We use GORE® BIO-A® Tissue Reinforcement often at our center because it provides a good balance of the characteristics relevant to performing the procedure and to outcome.” For all bioabsorbable products, rate of resorption is a critical issue. Although there is no clear clinical evidence that a rapid rate of resorption increases the risk for recurrent hernias, one theory explaining a potentially higher rate of failure with biologics in complicated cases is that bacterial processes accelerate resorption of this type of tissue.26,27 High rates of failure would be expected if the scaffolding degrades before tissue ingrowth provides adequate strength to prevent reherniation. Engineering of biosynthetic materials has the potential to permit greater control over this variable. With a 3-D matrix of highly interconnected pores, GORE® BIO-A® Tissue Reinforcement provides pores for cell migration, resulting in a structure that is similar to a collagen fiber network. The co-polymer, non“biologic” material has a predictable degradation profile and is less susceptible to premature degradation by collagenase. Therefore, GORE® BIO-A® Tissue Reinforcement maintains scaffolding for a long enough duration until ingrowth of native tissue is viable; however, the material still achieves resorption before an increased risk occurs for late complications from indwelling exogenous material. GORE® BIO-A® Tissue Reinforcement undergoes a relatively consistent and predictable hydrolytic degradation so that the resorption is complete in approximately 6 to 7 months.16 For example, in one study, a biosynthetic that had not been resorbed completely by 1 year induced a similar risk for foreign-body reactions as a synthetic mesh for which there was no degradation over this period.24 Resorption of GORE® BIO-A® Tissue Reinforcement, which also was included in that study, was complete prior to the 1-year analysis mark and was not associated with any inflammation or adhesion formation.24 “Clinical outcomes comparing biologics to biosynthetics may vary relative to the long-term recurrence rate,” Dr. Matthews said. “This is why we need to compare these meshes over periods of 4 to 5 years. The most significant

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difference between bioabsorbables, whether biologics or biosynthetics, may be the quality of the tissue they leave behind after reabsorption.” Some of the performance characteristics of surgical meshes, such as shape memory and ease of placement, are difficult to quantify, but are empirically understood by surgeons who work with these materials frequently. “In the early days of tissue reinforcement, we used heavyweight synthetic meshes. Strength was considered an important criterion,” Dr. Chao noted. “Biologics provided an opportunity to orchestrate tissue restoration, but these meshes still need to maintain sufficient mechanical strength to avoid early failure of the repair. With an array of biologic and biosynthetic meshes now available, there is an appreciation for ease of use in the surgical field.”

GORE® BIO-A® Tissue Reinforcement: Clinical Outcomes The scarcity of prospective data from a large series of patients treated at multiple centers has been the limiting factor in resolving the debate about specific features of surgical mesh materials overall, and the relative efficacy of biologic and biosynthetic meshes specifically. “Many of the specific design features of biologic and biosynthetic meshes that are now available may be important, but they are largely marketing concepts until we have the data to demonstrate that they influence outcome. Many of the biologic meshes have been available for more than 10 years with very little clinical evidence with which to judge efficacy. The same is now occurring with biosynthetic products,” Dr. Matthews said. “As a company willing to evaluate their product with a prospective trial, the manufacturers of GORE® BIO-A® Tissue Reinforcement, at this point, stand alone.” Although COBRA does not include a biologic mesh arm, outcome data with GORE® BIO-A® Tissue Reinforcement will provide a benchmark for mesh performance. There is a small case series supporting comparable benefit from GORE® BIO-A® Tissue Reinforcement relative to a biologic mesh, such as a single-center experience that found GORE® BIO-A® Tissue Reinforcement easier to use, as effective, and far less costly than a biologic mesh,8 but the quality of currently available data on biologics and biosynthetics has frustrated many experts in this area. “We and others have been involved in extensive animal studies with different mesh materials, but we have had very little in the way of clinical outcomes data. This is why there is so much interest in the COBRA study,” Dr. Heniford said. “The need for data is particularly great in contaminated wounds because

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many use biologics in these cases largely based on how this field evolved, but not on the basis of objective data. Practice would change if there were better evidence that biosynthetic mesh provided reliable outcomes in this group.” The stratifications in COBRA also may provide insight about performance of GORE® BIO-A® Tissue Reinforcement in groups known to have an increased risk for reherniation. “In an otherwise healthy population, infection rates after a laparotomy are low, but they climb steeply with welldefined risk factors, such as smoking, diabetes, or obesity. The relative risk for infection is an outcome relevant to comparing surgical mesh products, and these may differ,” Dr. Heniford added.

Importance of Follow-Up Data For clinicians active in this field, including Drs. Matthews, Chao, Jacobsen, and Heniford, one source of data has been their own patient series. Data on ventral hernia repair are being systematically collected at all 4 of the centers where they practice. For several, follow-up data with GORE® BIO-A® Tissue Reinforcement now extends to 3 years or more. Their interest in the COBRA results is driven in part by an experience that has been encouraging. “We presented an abstract at the recent AHS meeting in which we reported on 98 cases in which we used GORE® BIO-A® Tissue Reinforcement surgical mesh. Seventy-five percent of the cases were clean, and the remaining were either clean-contaminated or contaminated. There have been no unexpected late complications, and the recurrence rates have been as good or better with the amount of follow-up so far when compared with our experience with biologics,” Dr. Jacobsen reported. “In a few cases where we have obtained biopsies at the site of repair, we have seen a reassuring degree of collagen deposition and vascularization.” However, he suggested that 5-year data might be more revealing because of the risk for late recurrences with any hernia repair and the potential for a biosynthetic to perform better than a biologic mesh at this time point. Drs. Matthews, Chao, and Heniford, who also periodically have reviewed their own outcomes data with GORE® BIO-A® Tissue Reinforcement as well as other surgical meshes, made similar remarks. Each suggested that there have been no unexpected complications so far, but feel that at least 5 years of follow-up data are prudent to judge whether one mesh type is superior to another. “Late failures are common with mesh repairs, so long-term results are needed. If we can show greater durability of the repair with a biosynthetic, then this would be a significant advantage,” Dr. Matthews said.


REPORT

Substantial clinical experience with GORE ® BIO-A® Tissue Reinforcement has been presented at society meetings and forums. In a retrospective comparison of GORE® BIO-A® Tissue Reinforcement with no tissue reinforcement for ostomy closure, the rate of infections was low but similar in both groups. However, the authors noted that opening of the wound to treat the infection did not require removal of the mesh. All 3 recurrences in a study of 28 patients occurred in those who did not receive GORE® BIO-A® Tissue Reinforcement.28 In an early series of 34 cases of hernia repair with GORE ® BIO-A® Tissue Reinforcement, of which 47% were recurrent hernia repairs, there were no recurrences in up to 2 years of follow-up. Although only a few patients in this series had contaminated wounds, outcomes were not different in this subgroup.29 In a smaller study of abdominal wall reconstruction in a series of 5 patients, all of whom had a contaminated surgical field, there were no complications or recurrences at 6 months.30 In 2 complicated patients, who required relatively large sheets of GORE® BIO-A® Tissue Reinforcement mesh, reported outcomes also were favorable.31 One patient had a small bowel obstruction and perforation with numerous intraabdominal abscesses. In the other, an abscess and enterocutaneous fistula required drainage before placement of the mesh. No complications were observed in a 7-month follow-up, according to the authors.31 The authors noted the low cost of GORE® BIO-A® Tissue Reinforcement in relation to biologics and the ability to place the mesh without soaking or other preparation were listed as potential advantages over biologic prostheses.31 Together, these experiences, which document a growing clinical experience with GORE® BIO-A® Tissue Reinforcement in diverse settings and patient types, have provided the impetus for larger, systematic studies with long-term follow-up. When such studies are stratified for important variables, such as the size of the wound repair, patient comorbidities, and the relative contamination status of the operative field, the data have the potential to provide an evidence base for surgical mesh selection.

GORE® BIO-A® Tissue Reinforcement: Experience in Hiatal Hernias and Beyond The advantages of a bioabsorbable biosynthetic mesh in abdominal wall repair are likely to be applicable to other surgical repairs where tissue reinforcement may be of value but where a permanent prosthesis poses an unacceptable risk for complications. Published studies and clinical series presented in abstract form have chronicled the experience with GORE ® BIO-A® Tissue Reinforcement for a variety of

applications. The greatest experience has been in hiatal hernia repairs,32 but large paraesophageal repairs, stoma fixation, and repair of traumatic injuries also have been published 33 or are being pursued. “The experience with GORE® BIO-A® Tissue Reinforcement at many centers has been largely confined to ventral hernia repair, but the qualities of resorption are attractive for other types of surgeries. This is an area where we may see an expansion of the use of this product and other biosynthetic meshes,” Dr. Heniford said. Other clinical applications where tissue reinforcement may be of benefit, such as stoma or traumatic wound repair, have been proposed. In such procedures, the value of synthetic mesh has been limited by concern for complications from permanent placement of foreign-body material. With biosynthetic mesh that offers predictable performance—particularly complete resorption—at a lower cost than biologic meshes, the clinical applications may expand. The growing experience with biosynthetic mesh in hiatal hernia repair has provided evidence of good short-term results for this indication but may be equally important for suggesting that this material has potential applications outside of abdominal wall repair.

Economics of Tissue Reinforcement The relative efficacy of different types of surgical mesh under specific clinical circumstances has enormous implications for health care costs. Although the acquisition costs of surgical mesh products range widely, total costs are informed by a long list of variables ranging from operating time to failure rates. The difference in cost has been important motivation for developing biosynthetic surgical mesh as an alternative to biologics. The acquisition cost of a square centimeter of biologic mesh has been estimated to be approximately 5 times greater than that of a biosynthetic mesh.7 If surgical outcomes achieved with biosynthetic mesh are comparable to those achieved with biologic prostheses, the relative cost advantage of the biosynthetic material may be beyond the cost of acquisition. Unlike biologic mesh, which often requires preoperative preparation that may affect operating room (OR) efficiency,34 a biosynthetic mesh such as GORE® BIO-A® Tissue Reinforcement is designed to be used without having to perform preoperative tasks, such as soaking.16 “Cost was a major driver for us to move away from biologics in cases where we feel that biosynthetic mesh will perform as well. At our center, the cost of a biosynthetic mesh is a small fraction of that of a biologic,” Dr. Jacobsen reported. Mesh costs have a potentially large effect on the bottom line in hospitals where a high number of ventral hernia repairs are performed, according to a recent financial analysis. In this

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study of 415 patients undergoing ventral hernia repair, net revenue, direct costs, and indirect costs were evaluated.34 The analysis revealed a median net financial loss of $8,370 for repairs performed with a biologic mesh. In contrast, the repairs with synthetic mesh were characterized as budgetneutral (small median net profit).35 As a result of widespread use of biologics, hernia repair was being provided, on average, at a net loss from the perspective of the tertiary medical center where the study was conducted.35 Although this analysis ignores the impact of hernia recurrence with either type of mesh from the patient’s perspective, the data illustrate the effect of mesh choice for hospital costs. “Costs are complicated because reoperation may be the largest cost of all if you are evaluating the higher acquisition cost of a prosthesis that will provide a lower rate of recurrence,” Dr. Chao said. “However, it is difficult to consider the price of a mesh in isolation from all the variables that establish the value of one product over another.” Mesh acquisition costs drive economic comparisons from the hospital perspective, but relative rates of recurrence dominate mesh cost comparisons from the payor perspective. In a retrospective review of costs of placing a biologic mesh at a single institution, the authors concluded that the high rate of recurrence with biologic prostheses, despite their theoretical advantages in complex repairs, did not justify the expense.26 The unusually high rate of recurrence, which resulted in reoperation in 70% of the patients in a median follow-up of 24 months, 26 was the key factor behind this conclusion. The long-term durability of ventral hernia repair with a biologic mesh also was questioned in a study using the product type in contaminated settings. Results showed that out of 128 patients, 40 experienced hernia recurrence (31.3%) at approximately 21 months follow-up.36 While a majority of recurrences were asymptomatic and did not require additional surgery, repair was performed for 7 patients (17%) with a recurrence, which led authors to deem the performance of the biologic as less favorable overall.36 These results underline the potential distance between actual outcomes and theoretical advantages. “There is the risk that a price differential will be misunderstood as a quality differential. We are willing to use biologic meshes in the most complicated cases despite its cost because of the expectation that this will provide a better result. The problem is that this has never been shown directly,” Dr. Matthews said. “GORE® BIO-A® Tissue Reinforcement only has to perform as well as biologic mesh to become the standard because of the cost advantage.” In ventral hernia repair, outcomes drive costs. High rates of recurrence have driven the development of surgical mesh

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devices and ultimately define their value independent of cost. For payors, relapse requiring reoperation is a negative outcome from a cost perspective, but symptomatic recurrent hernias are a poor outcome for patients whether or not reoperation is required. “Working at an academic center, we think first about how a product performs and secondly about how much it costs,” Dr. Chao said. “Biosynthetic prostheses are attractive for the same principles that drew attention to biologics. It is critical that we compare these over the long term, at which time costs can be understood in terms of relative clinical benefit.”

Next Steps: Improving Care The optimal method of tissue reinforcement may not be the same for all indications or for patients stratified by comorbidities or other factors that influence outcome, but bioabsorbable mesh introduces the possibility of a physiologic repair. By encouraging tissue growth to reinforce sutured repair for restoring the integrity of the abdominal wall,16 there may be an opportunity for a sustained and permanent repair that is not possible with permanent synthetic devices in complex cases. “We have learned a lot about biosynthetics, and I believe that polymer mesh products will prove to be more effective than biologics ultimately,” Dr. Matthews said. He cited studies that have helped define the optimal pore size in 3-D matrix scaffolds, progress in mixing polymers to control and vary rates of degradation, and the potential to vary mesh flexibility to suit specific applications. Based on evidence that biologics and GORE® BIO-A® Tissue Reinforcement do induce viable ingrowth and vascularization,16 another potential advance is to enhance these qualities. Patient-related factors also may increase the desirability to use a biosynthetic product. Fully resorbable biosynthetic prostheses may be preferable for patients resistant to animal or cadaver material driven by personal choice. Also, patients may want to avoid stretching observed with select biologics, which can lead to visible abdominal bulges and, in some cases, the need for reconstruction.37 Thus, the use of a biosynthetic product may assuage those concerns. Nevertheless, measurable progress derived from any innovation depends on outcomes data against established devices with known risk–benefit ratios. Surgical mesh development has advanced largely in the absence of clinical studies capable of establishing benchmark performance meaningful for outcomes such as long-term freedom from hernia recurrence. In clean-contaminated and contaminated ventral hernia repairs, the prospective COBRA study with GORE ® BIO-A® Tissue Reinforcement will provide a meaningful demonstration of biosynthetic mesh repair.


REPORT

Conclusion The high recurrence rates after abdominal wall repair following laparotomy have provided a basis for innovation in tissue reinforcement.1 The limitations of synthetic materials, particularly in potentially contaminated surgical fields, have driven the effort to create a bioabsorbable mesh that will be resorbed after providing support at the site of repair. One of the most studied currently available biosynthetic prosthetics, GORE® BIO-A® Tissue Reinforcement, has the potential to offer more reliability in hernia repair than biologic mesh. The COBRA study19 study will provide more evidence on the efficacy in hernia repair. GORE® BIO-A® Tissue Reinforcement offers proven clinical outcomes at considerable economic value, making it a preferable choice in soft tissue reconstruction.

References 1. Luijendijk RW, Hop WC, van den Tol MP, et al. A comparison of suture repair with mesh repair for incisional hernia. N Engl J Med. 2000;343(6):392-398. 2. Klosterhalfen B, Junge K, Klinge U. The lightweight and large porous mesh concept for hernia repair. Expert Rev Med Devices. 2005;2(1):103-117. 3. van’t Riet M, de Vos van Steenwijk PJ, Bonjer HJ, et al. Mesh repair for postoperative wound dehiscence in the presence of infection: is absorbable mesh safer than non-absorbable mesh? Hernia. 2007;11(5):409-413. 4. Meintjes J, Yan S, Zhou L, et al. Synthetic, biological and composite scaffolds for abdominal wall reconstruction. Expert Rev Med Devices. 2011;8(2):275-288. 5. Ko JH, Wang EC, Salvay DM, et al. Abdominal wall reconstruction: lessons learned from 200 “components separation” procedures. Arch Surg. 2009;144(11):1047-1055. 6. Bhangu A, Fitzgerald JE, Singh P, et al. Systematic review and meta-analysis of prophylactic mesh placement for prevention of incisional hernia following midline laparotomy. Hernia. 2013 May 28. [Epub ahead of print] 7. Doerhoff CR. Use of biosynthetic absorbable mesh instead of biologics. Presented at: 14th Annual Hernia Repair Meeting; March 16-19, 2011; San Francisco, CA. Abstract P-1021. 8. W.L. Gore & Associates, Inc. Gore changes landscape in soft tissue repair with GORE BIO-A Tissue Reinforcement. www. gore.com/en_xx/news/bio-a.html. Accessed July 25, 2013. 9. Nguyen NT, Longoria M, Welbourne S, et al. Glycolide copolymer staple-line reinforcement reduces staple site bleeding during laparoscopic gastric bypass: a prospective randomized trial. Arch Surg. 2005;140(8):773-778. 10. de Vries Reilingh TS, van Goor H, Charbon JA, et al. Repair of giant midline abdominal wall hernias: “components separation technique” versus prosthetic repair: interim analysis of a randomized controlled trial. World J Surg. 2007;31(4):756-763.

11. Le D, Deveney CW, Reaven NL, et al. Mesh choice in ventral hernia repair: so many choices, so little time. Am J Surg. 2013; 205(5):602-607, discussion 607. 12. Hodde J, Hiles M. Constructive soft tissue remodelling with a biologic extracellular matrix graft: overview and review of the clinical literature. Acta Chir Belg. 2007;107(6):641-647. 13. Gupta A, Zahriya K, Mullens PL, et al. Ventral herniorrhaphy: experience with two different biosynthetic mesh materials, Surgisis and AlloDerm. Hernia. 2006;10(5):419-425. 14. Rosen MJ. Polyester-based mesh for ventral hernia repair: is it safe? Am J Surg. 2009;197(3):353-359. 15. Robinson TN, Clarke JH, Schoen J, et al. Major mesh-related complications following hernia repair: events reported to the Food and Drug Administration. Surg Endosc. 2005;19(12):1556-1560. 16. W.L. Gore & Associates, Inc. GORE® BIO-A® Tissue Reinforcement product brochure. www.goremedical.com/resources/dam/ assets/AQ3037-EN2.pdf. Accessed July 25, 2013. 17. Zemlyak AY, Colavita PD, Tsirline VB, et al. Absorbable glycolic acid/ trimethylene carbonate synthetic mesh demonstrates superior ingrowth and collagen deposition. Presented at: 2012 Abdominal Wall Reconstruction Conference; June 13-16, 2012; Washington, DC. 18. Itani KM, Rosen M, Vargo D, et al; RICH Study Group. Prospective study of single-stage repair of contaminated hernias using a biologic porcine tissue matrix: the RICH Study. Surgery. 2012;152(3): 498-505. 19. Rosen M, Bauer J, Carbonel A, et al. Quality of life improves after complex ventral hernia repair using a bioabsorbable material: preliminary results of a prospective, multicenter study. Presented at: 15th American Hernia Society Annual Hernia Repair Conference; March 13-16, 2013; Orlando, FL. 20. Rosen M, Bauer J, Carbonel A, et al. Complex ventral hernia repair using a bioabsorbable material: preliminary outcome of a prospective, multicenter study. Presented at: 2012 American College of Surgeons Annual Clinical Congress; September 30–October 4, 2012; Chicago, IL. 21. de la Portilla F, Zbar AP, Rada R, et al. Bioabsorbable staple-line reinforcement to reduce staple-line bleeding in the transection of mesenteric vessels during laparoscopic colorectal resection: a pilot study. Tech Coloproctol. 2006;10(4):335-338. 22. Tucker JG, Copher JC, Reilly JP, et al. The use of bioabsorbable Seamguard during laparoscopic appendectomy. Surg Laparosc Endosc Percutan Tech. 2007;17(2):83-85. 23. Pascual G, Sotomayor S, Rodriguez M, et al. Repair of abdominal wall defects with biodegradable laminar prostheses: polymeric or biological? PLoS One. 2012;7(12):e52628. 24. Peeters E, van Barneveld KW, Schreinemacher MH, et al. Oneyear outcome of biological and synthetic bioabsorbable meshes for augmentation of large abdominal wall defects in a rabbit model. J Surg Res. 2013;180(2):274-283. 25. Lopez-Cano M, Armengol M, Quiles MT, et al. Preventive midline laparotomy closure with a new bioabsorbable mesh: an experimental study. J Surg Res. 2013;181(1):160-169.

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26. Blatnik J, Jin J, Rosen M. Abdominal hernia repair with bridging acellular dermal matrix—an expensive hernia sac. Am J Surg. 2008;196(1):47-50. 27. Candage R, Jones K, Luchette FA, et al. Use of human acellular dermal matrix for hernia repair: friend or foe? Surgery. 2008;144(4):703-709, discussion 709-711. 28. Ramanujam P, Najafian H, Motamedi P, et al. The use of bioabsorbable mesh in ostomy closure. Presented at: 2012 Society of American Gastrointestinal and Endoscopic Surgeons; March 7-10, 2012; San Diego, CA. Poster P066. 29. Jacobsen G. A new alternative to traditional biologics in complex abdominal wall reconstruction. Presented at: 14th Annual Hernia Repair Meeting; March 16-19, 2011; San Francisco, CA. Abstract P264. 30. Weiss C, Voeller G. Bioabsorbable synthetic mesh for abdominal wall reconstruction in a complex operative field. Presented at: 5th International Hernia Conference; March 28-31, 2012; New York, NY. Abstract P-1441. 31. Doerhoff CR, Teget P. New synthetic bioabsorbable mesh in open abdomen. Presented at: 33rd International Congress of the

European Hernia Society; May 10-13, 2011; Ghent, Belgium. Abstract P-074. 32. Reich J, Strom K, Pasquariello J, et al. Routine hiatal hernia repair in laparoscopic gastric banding. Surg Technol Int. 2010; 20:163-166. 33. Zehetner J, Demeester SR, Ayazi S, et al. Laparoscopic versus open repair of paraesophageal hernia: the second decade. J Am Coll Surg. 2011;212(5):813-820. 34. Rosen MJ. Biologic mesh for abdominal wall reconstruction: a critical appraisal. Am Surg. 2010;76(1):1-6. 35. Reynolds D, Davenport DL, Korosec RL, et al. Financial implications of ventral hernia repair: a hospital cost analysis. J Gastrointest Surg. 2013;17(1):159-166, discussion 166-167. 36. Rosen MJ, Krpata DM, Ermlich B, et al. A 5-year clinical experience with single-staged repairs of infected and contaminated abdominal wall defects utilizing biologic mesh. Ann Surg. 2013; 257(6):991-996. 37. Bluebond-Langner R, Keifa ES, Mithani S, et al. Recurrent abdominal laxity following interpositional human acellular dermal matrix. Ann Plast Surg. 2008;60(1):76-80.

Refer to the Instructions for Use for a complete description of all warnings, precautions, and contraindications. Products listed may not be available in all markets. PERMACOL™ is a trademark of Covidien AG or its affiliate. FLEXHD™ is a trademark of Ethicon Inc. STRATTICE ® is a trademark of LifeCell Corporation. GORE®, BIO-A®, and designs are trademarks of W. L. Gore & Associates. © 2012 W. L. Gore & Associates, Inc. Gore products referenced within, if any, are used within their FDA approved/cleared indications. Gore does not have knowledge of the indications and FDA approval/clearance status of non-Gore products. Gore makes no representations as to the surgical techniques, medical conditions or other factors that may be described in the article(s). The reader is advised to contact the manufacturer for current and accurate information. AQ0061-EN1. Disclosures: Dr. Chao reported that he is a consultant for Novus Scientific; has received honoraria from LifeCell and Gore; and has received speaker fees from Boston Scientific. Dr. Heniford reported no relevant financial conflicts of interest. Dr. Jacobsen reported that he is a consultant to Ethicon, and has received grant/ research funding from Atrium Medical, Gore, and Linx Pharmaceutical. Dr. Matthews reported that he is a paid consultant for Gore; has received honoraria for speaking at educational forums for Gore; has received grant/research funding from Atrium Medical, Covidien, and Gore; and has received speaker fees from Atrium Medical, Bard, and Gore. Dr. Matthews has participated in the COBRA Trial as a co-investigator.

Copyright © 2013, McMahon Publishing, 545 West 45th Street, New York, NY 10036. Printed in the USA. All rights reserved, including the right of reproduction, in whole or in part, in any form.

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Disclaimer: This monograph is designed to be a summary of information. While it is detailed, it is not an exhaustive clinical review. McMahon Publishing, Gore, and the authors neither affirm nor deny the accuracy of the information contained herein. No liability will be assumed for the use of this monograph, and the absence of typographical errors is not guaranteed. Readers are strongly urged to consult any relevant primary literature.

General Surgery News International Edition - 2013  
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