SSAT - Physician Guidelines - Surgery for Obesity

SSAT Patient Care Guidelines

Surgery for Obesity

Introduction

Clinically severe obesity (CSO) is a prevalent health care problem throughout the world. In the United States, more than 6 million people currently suffer from this chronic disease. It has been estimated that obese individuals have a 5 to 12-fold increased risk of death as compared to age-matched controls.

The morbidity and mortality of CSO is related to associated medical co-morbid conditions that include, but are not limited to: heart disease, type 2 diabetes mellitus, obstructive sleep apnea, hypertension, dyslipidemia, gastroesophageal reflux disease, urinary stress incontinence, osteoarthritis, lower extremity edema, gynecologic disorders, and certain cancers.

Non-surgical treatments including diet, exercise, behavior modification, and medication have thus far proven to be ineffective. Surgical treatment of CSO has been well established as being safe and effective. Both short and long-term improvements of co-morbidities have been well documented. Recent studies suggest improved long-term survival in patients who have undergone bariatric surgical procedures.

Patients with clinically severe obesity typically have a long history of obesity and multiple failed attempts at weight loss. Patients may have multiple co-morbidities depending on the duration and severity of their obesity. A positive family history of obesity is common and suggests that hereditary factors play a strong role in the development of obesity.

Criteria for consideration for surgical therapy include:

Body mass index (BMI) of greater than 40 kg/m2 OR greater than 35 kg/m2 with obesity related medical co-morbidities.
A documented history of failed dietary attempts at weight control.
A commitment to, and mechanisms available for, life long follow-up.

Contraindications to surgical therapy include substance dependence, suicidal ideation, untreated eating disorders, and prohibitive medical conditions. Age <16 or >60, cirrhosis, inflammatory bowel disease, or a history of cancer within five years are all relative contraindications, and the decision to proceed with surgery should be made on an individual basis in these patients.

The overall care of patients undergoing 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 co-morbidities, dietary instruction, exercise training, specialized nursing care and psychological assistance as needed on an individual basis.

Bariatric surgical 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 (VBG). In the adjustable gastric band, the amount of restriction can be adjusted, while in the vertical banded gastroplasty, it remains fixed. The Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD) procedures also cause gastric restriction, but rely on varying amounts of intestinal malabsorption as an additional weight loss mechanism. An NIH conference in 1991 recognized vertical banded gastroplasty and Roux-en-Y gastric bypass as acceptable procedures based on available outcome data.

Minimally invasive approaches have been used in bariatric surgery since 1993. Potential benefits of a laparoscopic approach include shorter recovery and earlier return to normal activity. The indications for laparoscopic treatment of obesity are the same as for open surgery. Laparascopic bariatric surgery may not be possible in certain patients including those with extreme obesity, previous abdominal surgery, intolerance of pneumoperitioneum, or unsuitable body habitus.

Virtually all bariatric operations can be performed with laparoscopic techniques. 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. Prior to performing laparoscopic bariatric operations, surgeons must meet all local credentialing requirements for the performance of open bariatric procedures and advanced laparoscopic operations. Finally, these procedures require a well-trained operating team familiar with the equipment, instruments and techniques of weight loss surgery.

The risk of death following bariatric surgical procedures is approximately 1%. Risk factors predicting increased mortality include age, weight and male gender. Intraoperative complications include bleeding, inadvertent injury to the gastrointestinal tract and stapling misadventures (ie. stapling the NG tube). These occur rarely and morbidity can be minimized by prompt recognition and surgical correction. Early postoperative complications include pulmonary embolism (1-2%), anastomotic leaks (1-2%), wound infection or seroma, fascial dehiscence or evisceration (1%), gastrointestinal bleeding, small bowel obstruction, cardiorespiratory complications, and stomal stenosis. The development of symptomatic gallbladder disease is common in patients who have undergone bariatric surgical procedures and prophylactic cholecystectomy may be considered for patients with preexisting cholelithiasis. Some bariatric surgeons may place patients on ursodiol 600 mg per day as this has been shown to decrease the incidence of gallstone formation. Late complications include incisional hernia (10-20%), marginal ulceration (5-10%), small bowel obstruction, anemia, and nutritional deficiencies (iron, vitamin B12).

The employment of laparoscopic techniques results in significant improvements in the rates of wound complications, such as wound infection and incisional hernia. Anastomotic leak rates are slightly higher (5%), but appear to be improving with experience. Overall mortality is comparable to that achieved with open surgery.

It has been well established that the described procedures result in effective short and long-term weight loss. Approximately 70% of patients who have undergone RYGB will lose 50-70% of their excess body weight. It is crucial that patients have a realistic understanding of the expected outcomes of these procedures. Numerous studies demonstrate objective improvement in medical co-morbidities such as diabetes, congestive heart failure, musculoskeletal pain, sleep apnea, hypertension, and gynecological disorders. Finally, several recent reports suggest that bariatric surgical procedures (RYGB, VBG) may impart improved long-term survival in patients with CSO – particularly those who overcome the short-term morbidity and mortality of these procedures.

Although effective at inducing weight loss and improving medical co-morbities, the VBG appears to result in inferior results when compared to the RYGB. A notable subset of patients will suffer from weight regain and/or obstructive symptoms (“large pouch syndrome”) and many of these patients will require further surgical procedures to revise the VBG to a RYGB. Revisionary procedures are associated with an approximately 5-fold increased risk of anastomotic leak.

The malabsorptive procedures, such as the BPD, are effective in inducing weight loss, but may be associated with a higher incidence of metabolic complications. Additional data regarding their efficacy and safety will undoubtedly accumulate as experience with these procedures progresses.

Suggested Readings

NIH conference. Gastrointestinal surgery for severe obesity. Consensus Development Conference Panel. Ann Intern Med. Dec 15 1991;115(12):956-961
Baltasar A, Serra C, Perez N, Bou R, Bengochea M. Clinical hepatic impairment after the duodenal switch. Obes Surg. Jan 2004;14(1):77-83.
Belachew M, Legrand M, Vincent V, Lismonde M, Le Docte N, Deschamps V. Laparoscopic adjustable gastric banding. World J Surg. Sep 1998;22(9):955-963.
Christou NV, Sampalis JS, Liberman M, et al. Surgery decreases long-term mortality, morbidity, and health care use in morbidly obese patients. Ann Surg. Sep 2004;240(3):416-423; discussion 423-414.
Flum DR, Dellinger EP. Impact of gastric bypass operation on survival: a population-based analysis. J Am Coll Surg. Oct 2004;199(4):543-551.
Go MR, Muscarella P, 2nd, Needleman BJ, Cook CH, Melvin WS. Endoscopic management of stomal stenosis after Roux-en-Y gastric bypass. Surg Endosc. Jan 2004;18(1):56-59.
Gould JC, Needleman BJ, Ellison EC, Muscarella P, Schneider C, Melvin WS. Evolution of minimally invasive bariatric surgery. Surgery. Oct 2002;132(4):565-571; discussion 571-562.
Inge TH, Krebs NF, Garcia VF, et al. Bariatric surgery for severely overweight adolescents: concerns and recommendations. Pediatrics. Jul 2004;114(1):217-223.
Livingston EH, Huerta S, Arthur D, Lee S, De Shields S, Heber D. Male gender is a predictor of morbidity and age a predictor of mortality for patients undergoing gastric bypass surgery. Ann Surg. Nov 2002;236(5):576-582.
Nguyen NT, Goldman C, Rosenquist CJ, et al. Laparoscopic versus open gastric bypass: a randomized study of outcomes, quality of life, and costs. Ann Surg. Sep 2001;234(3):279-289; discussion 289-291.
Rubino F, Gagner M. Potential of surgery for curing type 2 diabetes mellitus. Ann Surg. Nov 2002;236(5):554-559.
Schauer PR, Ikramuddin S, Gourash W, Ramanathan R, Luketich J. Outcomes after laparoscopic Roux-en-Y gastric bypass for morbid obesity. Ann Surg. Oct 2000;232(4):515-529.
Scopinaro N, Adami GF, Marinari GM, et al. Biliopancreatic diversion. World J Surg. Sep 1998;22(9):936-946.
Sugerman HJ, Brewer WH, Shiffman ML, et al. A multicenter, placebo-controlled, randomized, double-blind, prospective trial of prophylactic ursodiol for the prevention of gallstone formation following gastric-bypass-induced rapid weight loss. Am J Surg. Jan 1995;169(1):91-96; discussion 96-97.
Wittgrove AC, Clark GW. Laparoscopic gastric bypass, Roux-en-Y- 500 patients: technique and results, with 3-60 month follow-up. Obes Surg. Jun 2000;10(3):233-239.

Keywords - adjustable gastric banding, bariatric surgery, biliopancreatic diversion, laparoscopy, minimally invasive surgery, obesity, Roux-en Y gastric bypass, vertical banded gastroplasty

Board Approved 04/22/2005

These patient care guidelines were written for the primary care physicians on a variety of digestive diseases to assist on when to refer the patient for surgical consultation.
Their goal is to guide PRIMARY CARE physicians to the appropriate utilization of surgical procedures on the alimentary tract or related organs and they are based on critical review of the literature and expert opinion. Both of the latter sources of information result in a consensus that is recorded in the form of these Guidelines. The consensus addressses the range of acceptable clinical practice and should not be construed as a standard of care. These Guidelines require periodic revision to ensure that clinicians utilize procedures appropriately but the reader must realize that clinical judgment may justify a course of action outside of the recommendations contained herein.