Physician Quick Search
By Name:
By Specialty:
Your Healthy Update

Like us on Facebook
Text Size: S M L

Gastric Bypass Surgery

Gastric bypass surgery is considered by many to be the current gold standard procedure for bariatric surgery and as of 2009, is the most frequently performed procedure for weight loss.


Gastric Bypass Specialist:

J. Christopher Eagon, MD

  Gastric bypass is a choice for people who
  • have a BMI of 40 or greater
  • are 100 pounds or more above ideal body weight
  • have a BMI greater than 35 with serious obesity-related complications such as diabetes, hypertension, sleep apnea or other medical conditions.
The most frequently performed procedure is the Roux-en-Y gastric bypass.  The traditional open version of this operation has been performed for more than 30 years; the laparoscopic version of the gastric bypass has become increasingly common over the past decade. Experience is very important with laparoscopic surgery - your surgeon should have performed at least 75 procedures with laparoscopy to be considered proficient. The surgeons at Washington University School of Medicine routinely teach other surgeons how to perform laparoscopic surgery successfully.

In laparoscopic surgery, the surgeon uses a small video camera inserted into the abdomen, which allows him or her to conduct and view the surgery on a video monitor.  The camera and surgical instruments use several keyhole-sized incisions in the abdominal wall instead of cutting across the abdomen. Laparoscopic procedures for weight loss surgery employ the same principles as the open counterpart and produce similar excess weight loss.

Compared to open surgery, some benefits of the laparoscopic approach include less postoperative pain, fewer wound infections, fewer incisional hernias and faster recovery and return to the presurgical level of activity.  Laparoscipic surgery is not appropriate for everyone.  For people who weigh more than 450 pounds, who have had previous stomach surgery or who have a lot of scar tissue in the abdomen, the open procedure is usually prescribed. Dr. Eagon, national leader in laparoscopic bariatric surgery, will advise you of your best option.

The Principle

In gastric bypass surgery, the surgeon wants to restrict the amount of food that is taken into the digestive system and to reduce the efficiency of the absorption in the intestines.  This two-step process is done by dividing the stomach into a small and a large section, and revising the stomach-intestine outlet farther down the intestinal tract, thereby "bypassing" the larger part of the stomach and most of the small intestine (duodenum).

The Procedure

The Roux-en-Y bypass is done under general anesthesia. 

In open surgery, a traditional incision (12 to 24 inches) is made in the abdomen. The laparoscopic procedure uses six small incisions (each less than one-third of an inch) across the upper abdomen so the surgeon can insert laparoscopic instruments and stapling devices.

  • One year after surgery, weight loss can average 77 percent of excess body weight.
  • Studies show that after 10-14 years, 60 percent of excess body weight loss has been maintained by patients
  • A 2004 meta-analysis of more than 22,000 patients showed that those who underwent a bariatric surgical procedure experienced complete resolution or improvement of their co-morbid conditions including diabetes, high cholesterol, hypertension and obstructive sleep apnea.

All surgeries carry risks, but in addition to those risks associated with general surgery are the following complications to the digestive tract:
  • Because the duodenum is bypassed, poor absorption of iron and calcium can result in the lowering of total body iron and a predisposition to iron deficiency anemia.  Women should be aware of the potential for heightened bone calcium loss.
  • Bypassing the duodenum has caused metabolic bone disease in some patients, resulting in bone pain, loss of height, humped back and fractures of the ribs and hip bones.  All of these deficiencies can be managed through proper diet and vitamin supplements
  • Chronic anemia due to vitamin B12 deficiency can occur.  This can usually be managed with vitamin B12 pills or injections.
  • When then the pylorus is removed or bypassed, a condition known as dumping syndrome can occur as a result of rapid emptying of stomach contents into the small intestine.  This is sometimes triggered when too much sugar or large amounts of food are consumed. While generally not considered to be a serious risk to your health, the results can be extremely unpleasant and can include nausea, weakness, sweating, faintness and on occasion, diarrhea after eating.
  • In some cases, the effectiveness of the procedure may be reduced if the stomach pouch is stretched and/or if it is initially left larger than 15 to 30 cc.
  • Rerouting of bile, pancreatic and other digestive juices beyond the stomach can cause intestinal irritation and ulcers.
  • The lower stomach pouch and segments of the small intestine cannot be easily visualized using x-ray or endoscopy if problems like ulcers, bleeding or malignancy should occur.
Post Surgical Care

Most patients start on a liquid diet and begin walking the day after surgery. Generally, laparoscopic patients are ready to go home on the second or third day after surgery. If a traditional incision is required, expect the hospital stay to be four to five days.

In most people who have gastric bypass, the diet progresses from liquids to pureed foods to a regular diet over six weeks. Weight loss and resolution of diabetes and other obesity-related diseases such as sleep apnea, high blood pressure and arthritis occur gradually over the months after surgery. Patients lose an average of 70 percent of their excess body weight during the first year after surgery and then their weight stabilizes.

For More Information

For more information, forms  and instructions on pre and post surgery requirements, please visit the weight loss surgery information on the Washington University Surgery web site.
Washington University Physicians are the medical staff of  Barnes-Jewish Hospital and Children's Hospital - St. Louis Employment   About Us   Top Stories   For Your Protection      Site Map
Copyright 2015 Washington University School of Medicine
Copyright 2015 Washington University School of Medicine