The Roux-en-Y gastric bypass is the most common and successful type of gastric bypass procedure. The surgeon begins by creating a small pouch by dividing the upper end of the stomach. This restricts the intake of food. Next, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the lower stomach, the duodenum (the first segment of the small intestine), as well as the first portion of the jejunum (the second segment of the small intestine). The procedure creates a direct connection from the stomach to the lower segment of the small intestine, literally bypassing portions of the digestive tract that absorb calories and nutrients.

Expected Weight Loss

Patients who have malabsorptive surgery generally lose one-half to two-thirds of their excess weight within two years. The weight loss generally continues for a year and a half before stabilizing.

Benefits of Bypass Surgery

Few surgical risks and more weight loss

Unlike bypass procedures that involve removal of the stomach, the Roux-en-Y approach poses fewer operative risks. Malabsorptive procedures, like the Roux-en-Y, produce more weight loss than restrictive surgeries and are more effective in reversing the health problems associated with severe obesity. Patients feel full after eating about two tablespoons of food. Due to some malabsorption, nutritional supplements are necessary.

Surgical Risks

Complications can be avoided with proper care

First, you should know that all surgical procedures have risks, particularly for morbidly obese individuals. Discuss potential risks of surgery with your surgeon so that you are prepared to make an informed choice.

The risk of complications and nutritional deficiencies is higher with a more extensive bypass operation. Patients with extensive bypasses of the normal digestive process require not only close monitoring, but also lifelong use of special foods and medications. Ten percent to 20 percent of patients who have weight loss operations require follow-up operations to correct complications. Abdominal hernias are the most common complications requiring follow-up surgery.

Complications also may include leakage through staples or sutures, bowel obstruction, ulcers in the stomach or small intestine, blood clots in the lungs or legs, stretching of the pouch or esophagus, recurring vomiting and abdominal pain, inflammation of the gallbladder, and failure to lose weight.

More than one-third of obese patients who have gastric bypass surgery develop gallstones (clumps of cholesterol and other matter that form in the gallbladder). During rapid or substantial weight loss, a person’s risk of developing gallstones is increased. Gallstones can be prevented with bile salt supplements taken for the first six months after surgery.

Nearly 30 percent of patients who have weight loss surgery develop nutritional deficiencies such as anemia, osteoporosis and metabolic bone disease. These deficiencies can be avoided if vitamin and mineral intakes are maintained.

Dumping syndrome”, in which consumption of certain foods and beverages causes abdominal cramping and diarrhea, can also occur. Your registered dietitian will explain how to prevent dumping syndrome.

Finally, you should know that surgeons with more experience performing this procedure report fewer complications.

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