The fundamental basis for bariatric surgery for the purpose of accomplishing weight loss is the determination that severe obesity is a disease associated with multiple adverse effects on health which can be reversed or improved by successful weight loss in patients who have been unable to sustain weight loss by non-surgical means. It even helps in the reduction of cardiovascular disease (CVD) as well as other expected benefits of this intervention. The ultimate benefit of weight reduction relates to the reduction of the co-morbidities, quality of life and all-cause mortality.
Specific criteria established by the NIH consensus panel indicated that bariatric surgery is appropriate for all patients with BMI (kg/m2) >40 and for patients with BMI 35-40 with associated comorbid conditions. These standards have held up over the long years, although specific indications for bariatric/metabolic surgical intervention have been recognized for persons with less severe obesity, such as persons with BMI 30-35 with type 2 diabetes. The indications for bariatric surgery are evolving rapidly to consider the presence or absence of comorbid conditions as well as the severity of the obesity, as reflected by BMI.
Specific Bariatric Surgical Procedures are Roux-en-Y Gastric Bypass (RYGB), Sleeve Gastrectomy, Biliopancreatic diversion with duodenal switch, Implantation of Devices (includes Adjustable Gastric Banding, Intermittent vagal blockade, Gastrointestinal Endoscopic Devices).
Bariatric surgical community enacted a number of changes to result in this improved safety record. Included is the identification of the importance of surgeon and center experience, the establishment of pathways, care protocols, and quality initiatives and incorporation of all of these aspects of care into an accreditation of centers program. The transition to laparoscopic methodology occurred during the same time period and also contributed to the improved safety.
Weight loss following bariatric surgery has been studied and reported both short- and longer-term following all surgical procedures undertaken, as weight loss is the primary objective of bariatric surgery. Mean weight loss is uniformly reported. It is crucial to identify however, the high variability of weight loss following apparently standardized operative procedures such as RYGB or Laparoscopic Adjustable Gastric Banding (LAGB).