Note: This guideline has been updated. The National Guideline Clearinghouse (NGC) is working to update this summary. The recommendations that follow are based on the previous version of the guideline.
Indications for Surgery
Surgical therapy should be considered for individuals who:
- have a body mass index (BMI) equal to or greater than 40 kg/m2 OR
- have a BMI equal to or greater than 35 kg/m2 and significant comorbidities AND
- can show that dietary attempts at weight control have been ineffective
Perioperative and Long Term Management Considerations
The overall care of patients undergoing operatively induced weight loss (bariatric surgery) requires programs that address both perioperative care and long-term management. Careful preoperative evaluation and patient preparation are critical to success. Patients should have a clear understanding of expected benefits, risks, and long-term consequences of surgical treatment. Surgeons must know how to diagnose and manage complications specific to bariatric surgery. Patients require lifelong follow-up with nutritional counseling and biochemical surveillance. Surgeons also must understand the requirements of severely obese patients in terms of facilities, supplies, equipment, and staff necessary to meet these needs, and should ensure that the specialized staff and/or multi-disciplinary referral system is included in treatment of these patients. This multi-disciplinary approach includes medical management of comorbidities, dietary instruction, exercise training, specialized nursing care, and psychological assistance as needed on an individual basis. Postoperative management of comorbidities should be directed by a practitioner familiar with relevant bariatric operations.
Surgical Techniques
Bariatric procedures rely on two primary mechanisms to promote weight loss: gastric restriction and intestinal malabsorption. Purely restrictive operations include various gastric banding procedures and the vertical banded gastroplasty. In the adjustable gastric band the amount of restriction can be adjusted, while in the vertical banded gastroplasty it remains fixed. The gastric bypass and biliopancreatic diversion procedures also cause gastric restriction but rely on varying amounts of intestinal malabsorption as an additional weight loss mechanism. Increasingly, hormonal changes are being recognized as an important mechanism of postsurgical weight loss; recent studies have demonstrated that gastric bypass results in altered release of hunger-causing hormones, such as ghrelin (Cummings et al., 2002).
The National Institute of Health (NIH) conference of 1991 recognized the vertical banded gastroplasty and gastric bypass as acceptable procedures based on available outcome data ("Gastrointestinal surgery for severe obesity," 1992). Regardless of whether restrictive or combined restrictive-malabsorptive procedures are utilized, follow-up is imperative to monitor for potential serious sequelae and operative failure. These operations should only be performed within the setting of an obesity treatment program committed to maintaining long-term follow-up for evaluation of outcomes (Cummings et al., 2002).
Minimally invasive approaches have been used in bariatric surgery since 1993 (Kuzmak, 1991; Wittgrove & Clark, 2000). The benefits of a laparoscopic approach appear to be similar to those realized with laparoscopic cholecystectomy, including but not limited to a shorter recovery with an earlier return to normal activity. In addition, wound complications such as infection, abdominal wall hernia, seroma, and hematoma (Nguyen et al., 2000) are significantly reduced. Overall outcome following laparoscopic weight loss surgery appears to be comparable to that following equivalent open procedures (Schauer et al., 2000).
The indications for laparoscopic treatment of obesity are the same as for open surgery and have been outlined earlier in this document. Not all patients are suitable for laparoscopic weight reduction surgery, and conversion to an open bariatric procedure is sometimes necessary. Surgeons performing bariatric procedures laparoscopically must have the skills, experience, and equipment necessary to convert to and perform open bariatric operations.
Virtually all bariatric operations can be performed with laparoscopic techniques (Kuzmak, 1991; Wittgrove & Clark, 2000; Nguyen et al., 2000; Schauer et al., 2000; Belachew et al., 1998; Chua & Mendiola, 1995; Lonroth et al., 1996; Catona, La Manna, & Forsell, 2000). For safe and effective laparoscopic treatment of obesity, advanced laparoscopic skills are required. Therefore, appropriate training in advanced laparoscopic techniques is mandatory. These skills are most appropriately acquired through a residency or fellowship or in courses that teach the indications for surgically inducing weight loss, the various surgical approaches (both open and laparoscopic), and the advanced technical skills necessary to perform these operations. Additionally, the long-term care of these patients needs to be understood. Prior to performing laparoscopic bariatric operations, surgeons must meet all local credentialing requirements for the performance of open bariatric procedures and advanced laparoscopic operations (Society of American Gastrointestinal Endoscopic Surgeons [SAGES], 1994). Credentialing guidelines for both open and laparoscopic bariatric procedures have been made available by several national surgical organizations (American Society of Bariatric Surgeons [ASBS], 2003). Finally, these procedures require a well-trained operating team familiar with the equipment, instruments, and techniques of weight loss surgery.
Summary
Morbid obesity is a significant health concern. Medical management usually fails to achieve sustained weight loss, and medical management of obesity-related morbidities remains expensive and largely ineffective. Currently, bariatric surgical procedures are the most effective means to achieve significant, sustained weight loss, and thereby provide effective and durable treatment of the obesity-associated morbidities. Laparoscopic approaches, based on their "open" counterparts, are available. When performed by appropriately trained surgeons, laparoscopic approaches appear to speed the patient's recovery and return to normal function. Experience and training in weight loss surgery, advanced laparoscopic surgery skills, and a commitment to long-term patient care are required for successful treatment of these patients.
