After the patient's multidisciplinary evaluation, obesity surgery should be considered in adults with a documented BMI greater than or equal to 35 and related comorbidity, or a BMI of at least 40. In addition to standard laboratory testing, chest radiography, electrocardiography, spirometry, and abdominal ultrasonography, the preoperative evaluation of obesity surgery patients also includes upper gastrointestinal endoscopy or radiologic evaluation with a barium meal. Psychiatric consultation and polysomnography can safely be restricted to patients with clinical symptoms on preoperative screening. Adjustable gastric banding (GB), vertical banded gastroplasty (VBG), Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD) are all effective in the treatment of morbid obesity, but differ in degree of weight loss and range of complications. The choice of procedure therefore should be tailored to the individual situation. There is evidence that a laparoscopic approach is advantageous for LAGB, VBG, and GB (and probably also for BPD). Antibiotic and antithromboembolic prophylaxis should be used routinely. Patients should be seen 3 to 8 times during the first postoperative year, 1 to 4 times during the second year and once or twice a year thereafter. Outcome assessment after surgery should include weight loss and maintainance, nutritional status, comorbidities and quality-of-life.

Early weight loss results were not different between the groups, but after 2 years the more restrictive LSG (groups 2, 3) results were significantly better than in patients without calibration. A removed gastric volume of <500 cc seems to be a predictor of failure in treatment or early weight regain. A statistically significant improved health status and quality of life were registered for all groups. The general introduction of LSG as a one-stage restrictive procedure in the bariatric field can be considered only if the procedure is standardized and long-term results are available.

In 2012, an outstanding expert panel derived from IFSO-EC (International Federation for the Surgery of Obesity -European Chapter) and EASO (European Association for the Study of Obesity), composed by key representatives of both Societies including past and present presidents together with EASO's OMTF (Obesity Management Task Force) chair, agreed to devote the joint Medico-Surgical Workshop of both institutions to the topic of metabolic surgery as a pre-satellite of the 2013 European Congress on Obesity (ECO) to be held in Liverpool given the extraordinarily advancement made specifically in this field during the past years. It was further agreed to revise and update the 2008 Interdisciplinary European Guidelines on Surgery of Severe Obesity produced in cooperation of both Societies by focusing in particular on the evidence gathered in relation to the effects on diabetes during this lustrum and the subsequent changes that have taken place in patient eligibility criteria. The expert panel composition allowed the coverage of key disciplines in the comprehensive management of obesity and obesity-associated diseases, aimed specifically at updating the clinical guidelines to reflect current knowledge, expertise and evidence-based data on metabolic and bariatric surgery.

In 2012, an outstanding expert panel derived from IFSO-EC (International Federation for the Surgery of Obesity -European Chapter) and EASO (European Association for the Study of Obesity), composed by key representatives of both Societies including past and present presidents together with EASO's OMTF (Obesity Management Task Force) chair, agreed to devote the joint Medico-Surgical Workshop of both institutions to the topic of metabolic surgery as a pre-satellite of the 2013 European Congress on Obesity (ECO) to be held in Liverpool given the extraordinarily advancement made specifically in this field during the past years. It was further agreed to revise and update the 2008 Interdisciplinary European Guidelines on Surgery of Severe Obesity produced in cooperation of both Societies by focusing in particular on the evidence gathered in relation to the effects on diabetes during this lustrum and the subsequent changes that have taken place in patient eligibility criteria. The expert panel composition allowed the coverage of key disciplines in the comprehensive management of obesity and obesity-associated diseases, aimed specifically at updating the clinical guidelines to reflect current knowledge, expertise and evidence-based data on metabolic and bariatric surgery.