The Duodenal Switch Operation for the Treatment of Morbid Obesity

Morbid obesity is defined as having a body mass index (BMI) of greater than 40 kg/m2 or being 100 lbs over ideal body weight as defined by the 1983 Metropolitan Life Insurance tables.1 Although environmental factors are clearly important, identical twin studies2 and ongoing elucidation of the functional roles of hormones such as leptin3,4 and ghrelin5 have shown that genetic and physiologic factors have a major role in the etiology of this disease. In the United States, morbid obesity has reached epidemic proportions. Two percent of the adult male and 6% of the adult female population, a total of approximately 12 million Americans, are morbidly obese. The disease is associated with an increased risk of serious comorbidities, including type II diabetes, sleep apnea, cardiovascular diseases, and orthopedic disabilities. It has recently been estimated that individuals with morbid obesity have a mortality risk similar to that of smokers.6 A 25-year-old male with a body mass index of 45 can expect to lose approximately 14 years of life.7 Nonoperative treatments for patients with morbid obesity have not been shown to produce reliable long-term benefit, consequently, surgical therapy has become the preferred treatment.8 It is estimated that 98,000 surgical procedures for the treatment of obesity will be performed in 2003, compared with 63,000 in 2002 and 47,000 in 2001.9 The 1991 National Institutes of Health consensus conference on morbid obesity recommended that surgery be considered for well-informed patients with acceptable operative risks.10 The intention of the conference, although often construed to be otherwise, was not to recommend or condemn a particular surgical procedure. Historically, the first surgical procedure designed to produce weight loss was the jejunoileal bypass in 1953.11 The severe hepatic, metabolic, and nutritional complications of this procedure12 led to the development of the loop gastric bypass,13 the vertical banded gastroplasty,14 and the Roux-en-Y gastric bypass.15 In 1979, Scopinaro described the biliopancreatic diversion procedure, combining a distal gastrectomy with a long-limb Roux-en-Y reconstruction to induce fat malabsorption.16 The duodenal switch procedure was described by DeMeester and colleagues in 1987 as a surgical solution for primary bile reflux gastritis or to decrease the postgastrectomy symptoms seen in patients after distal gastrectomy and gastroduodenostomy.17 Later that year, Hess adapted this procedure to the treatment of morbid obesity by adding a 75% longitudinal gastrectomy to reduce gastric capacity and acid production and extending the Roux limb to a length similar to that recommended by Scopinaro to induce fat malabsorption (Fig. 1). 18 Despite favorable reports on the use of the duodenal switch procedure for the treatment of morbid obesity,18–23 it has been slow to gain widespread popularity. There are 3 reasons for this. First, there is a perception that its malabsorptive component may be associated with metabolic complications, protein calorie malnutrition, or other nutrient deficiencies. Second, the procedure is longer and more technically demanding than other bariatric operations. Third, the procedure is difficult to perform laparoscopically. The aim of the current study is to report the results obtained over a 10-year period on the use of the duodenal switch procedure for the treatment of morbid obesity at a single institution, with a specific focus on its safety and efficacy. FIGURE 1. The duodenal switch procedure as performed at the University of Southern California for the treatment of morbid obesity. The operation consists of a 75% longitudinal gastrectomy, creation of an alimentary limb approximately 50% of total small ...