Endoluminal tactics may cut bariatric morbidity.
The use of endoluminal approaches to avoid any type of abdominal incision and, more importantly, any intra-abdominal dissection "may go a long way to further reduce the morbidity of these operations, making them cheaper and safer," Dr. Schauer said in an interview. "Potentially, they may expand the access for patients. Only 1% of patients with severe obesity are actually getting access to surgery, which is the only known therapy to be effective for a large percentage of patients."
Dr. Schauer, director of advanced laparoscopic and bariatric surgery at the bariatric and metabolic institute of the Cleveland Clinic, and his associates categorized the current endoluminal methods for weight loss therapy as presurgical endoluminal therapy, postsurgical endoluminal revision procedures, and primary procedures (Surg. Endosc. 2007;21:347-56).
In the presurgical endoluminal therapy arena, Dr. Michel Gagner and his associates pioneered a two-stage operation consisting of a sleeve gastrectomy followed by a Roux-en-Y gastric bypass (RYGB) or a duodenal switch (Obes. Surg. 2003;13:861-4).
"The rationale is that the first-stage operation, sleeve gastrectomy, is comparatively simple (requiring no anastomosis), needs less operative time (1-2 hours), and results in a predictable 40- to 50-kg weight loss," Dr. Schauer and his associates wrote in their review. "Such weight loss reduces the operative risk for the second-stage procedure, which presumably results in more weight loss and greater durability."
Dr. Gagner, professor of surgery and chief of bariatric surgery at Cornell University, New York, and his associates were also the first to publish results of an approach using the placement of endoluminal duodenojejunal tube or plastic sleeve to the first part of the duodenum proximal to the ampulla of Vater in pigs as a weight-loss strategy (Obes. Surg. 2006;16:620-6). This study, which demonstrated good weight loss in pigs, was the basis for the first human trial reported by Dr. Leonardo Rodriguez and his associates at the annual meeting of the American Society for Metabolic and Bariatric Surgery (formerly the American Society for Bariatric Surgery) in June 2007.
In the human trial, 12 patients from Chile and Brazil, including four with diabetes, underwent placement of a 61-cm endoluminal duodenojejunal tube or plastic sleeve that was anchored endoscopically in the duodenum and removed after 12 weeks.
All patients achieved an estimated weight loss of at least 10%, and 10 of the 12 patients lost an estimated 24% of their weight. All of the diabetic patients completed the study without the need for hypoglycemic medications.
"By diverting the flow of food from the duodenum and the proximal jejunum, we might be able to change some of the GI hormones that may switch the diabetes to reverse itself," Dr. Gagner said in an interview. "I think we will see more and more of that technology being developed, and we'll see variants like different materials, different lengths [of sleeves], et cetera." Dr. Gagner was not affiliated with the study.
In other studies of presurgical endoluminal therapy, the intragastric balloon developed by BioEnterics Corp. has been used successfully as a first-stage procedure to reduce presurgical weight and perioperative risk in superobese patients, but clinical results are limited.
In the arena of postsurgical endoluminal revision procedures, small studies of C.R. Bard Inc.'s EndoCinch suturing system and endoscopic suturing device have demonstrated promising results.
Dr. Christopher C. Thompson and his associates used the EndoCinch suturing system in eight patients who had undergone RYGB but had regained an average of 24 kg from baseline (Surg. Obes. Relat. Dis. 2005;1:223). They placed plications at the rim of the anastomosis, thereby reducing the anastomotic aperture. At 4 months after undergoing the procedure, six of the eight patients had lost an average of 10 kg, and four reported significant improvements in satiety.
In another study, Dr. Michael Schweitzer and his associates used the endoscopic suturing device in four patients who regained weight after RYGB surgery (J. Laparoendosc. Adv. Surg. Tech. A. 2004;14:223-6). The study did not include long-term results, but noted that all four patients reported improvements in early weight loss and satiety.
At the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons in April 2007, Dr. Roberto Fogel of Caracas, Venezuela, reported that an endoluminal vertical gastroplasty procedure produced an average excess weight loss of 46% in patients 3 months after surgery. In this procedure, an interrupted suture pattern was used in 31 patients with a mean body mass index of 38.1 kg/[m.sup.2]. In addition to the weight loss, reductions also were achieved in glucose intolerance or type 2 diabetes (from 14 patients to 2), hypertension (from 26 to 11), and dyslipidemia (from 27 to 11).
Such suturing procedures hold particular promise, Dr. Schauer said, because "they emulate gastric restriction, a concept that has been proven over several decades in bariatric surgery."
Dr. Schauer is one of the clinicians participating in the phase III RESTORe (Randomized Evaluation of Endoscopic Suturing Transorally for Anastomotic Outlet Reduction) trial for patients with inadequate weight loss following RYGB.
The purpose of the trial, which is supported by Bard and Davol Inc., is to evaluate weight loss and other clinical outcomes following application of transoral reduction of a dilated gastrojejunostomy anastomosis in 220 patients who have not achieved adequate weight loss following RYGB. The expected completion date of the trial is July 2008.
The use of endoluminal techniques for the primary treatment of obesity is in its infancy, Dr. Schauer said. One investigational device that has been studied in small trials of patients outside the United States is the transoral gastroplasty (TOGa) system, developed by Satiety Inc. In this procedure, an endoscopic stapling device is inserted through the mouth to the stomach to create a small restrictive pouch.
Dr. Gagner said that he is optimistic about such developments but cautioned that much more study is required before they are embraced by gastrointestinal endoscopic surgeons.
"It's great that we have this research effort going on, that there's a lot of enthusiasm," he said. "People think it's going to happen overnight. I think it's going to take much longer than what we think."
Dr. Schauer called the development of endoluminal techniques for obesity "another potential great leap forward in reducing the risk of these procedures. We already know that going from open procedures to laparoscopic procedures was one of the major factors that propelled bariatric surgery from a very low niche field [15,000 cases per year] across the United States, to 200,000 procedures per year. What really drove that was the reduction in complications and recovery."
Similar success with endoluminal techniques will take time, and will require the ability to overcome technical hurdles and challenges associated with reimbursement. "These procedures will require new CPT codes and applications to insurance carriers to get reimbursed," he said.
Dr. Schauer disclosed that he is a paid consultant for Bard, Davol, Ethicon Endo-Surgery Inc., Stryker Endoscopy, Baxter International Inc., W.L. Gore & Associates Inc., and Barosense Inc.
Dr. Gagner disclosed that he is a scientific adviser for Gl Dynamics Inc. He also has received research grants from Covidien AG, Olympus America Inc., and Bard.
BY DOUG BRUNK
San Diego Bureau
|Printer friendly Cite/link Email Feedback|
|Publication:||Internal Medicine News|
|Date:||Oct 1, 2007|
|Previous Article:||MRSA showing no mercy in skin infections.|
|Next Article:||Laparoscopic bypass offers advantages.|