Gastrointestinal Complications of Obesity Surgery

John E. Pandolfino, MD; Brintha Krishnamoorthy, BS; Thomas J. Lee, MD

In This Article

Bariatric Surgery

Bariatric surgery was first introduced in the 1950s and has evolved significantly since then Although there are multiple operative approaches, 2 main principles exist in combination, or alone, in the various procedures: restriction and malabsorption. The restrictive component limits the volume of solid food that can be ingested in a given period of time by mechanically decreasing the volume capacitance of the proximal stomach (eg, vertical banded gastroplasty and gastric banding). The malabsorptive component involves a diversionary operation in which part of the small intestine is bypassed, thereby establishing a partial, selective malabsorption (eg, gastric bypass and biliopancreatic diversion with or without duodenal switch).

Bariatric surgery is an appropriate treatment option with acceptable operative risks for well-informed, highly motivated patients who suffer from severe impairments secondary to their weight. Not all patients are candidates for these procedures, and optimal results are obtained with the involvement of a multidisciplinary team (including physician/surgeon, nutritionist, dietitian, psychologist, and/or psychiatrist).[5]

Current guidelines use the BMI classification scheme to identify patients at risk for developing adiposity-related complications. BMI represents the relationship between height and weight and is calculated as weight (kg) divided by height (m2). In 1991, a National Institutes of Health Consensus Conference proposed a risk-classification system based on BMI: Patients with a BMI of 25.0-29.9 are classified as overweight, and those with a BMI of 30 kg/ m2 or more are classified as obese. Obesity is further classified as high risk (class I, BMI 30-34.9 kg/m2), very high risk (class II, BMI 35-39.9 kg/m2), and extremely high risk (class III, BMI 40 kg/m2 or greater).[6] The National Institutes of Health concluded that patients with class III obesity (BMI 40 kg/m2 or greater) or those with class II obesity (BMI 35-39.9 kg/m2) and 1 or more severe, obesity-related medical problem(s) (eg, sleep apnea, hypertension, type 2 diabetes mellitus, and/or heart failure) are eligible for surgery.[6] Additionally, patients should have failed conventional weight-loss therapies, should have acceptable operative risks, and should be committed to comply with long-term treatment and follow-up.

Most bariatric surgeries have been performed laparoscopically with success. The laparoscopic approach is gaining favor because of shorter hospital stays, faster return to functional daily activities, improved cosmesis, decreased wound infections, lower incidence of incisional hernia, and less blood loss. In addition, the majority of studies have demonstrated that there is no difference in achieved weight loss after the open or laparoscopic procedure.[7,8,9,10,11] Laparoscopy, however, is not the preferred surgical approach for superobese patients (BMI ≥ 50 kg/m2) because of limitations in the physical anatomy of these individuals.


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