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Gastric Bypass Surgery

Laparoscopic gastric bypass surgery is the most commonly performed bariatric procedure worldwide

Gastric bypass surgery, also known as the Roux-en-Y Gastric Bypass, is considered the “gold standard” of weight loss surgery.

There are two components to the bariatric bypass surgery. First, a small stomach pouch, approximately one ounce in volume, is created by dividing the top of the stomach from the rest of the stomach. Next, the first portion of the small intestine is divided, and the bottom end of the divided small intestine is brought up and connected to the newly created small stomach pouch. The procedure is completed by connecting the top portion of the divided small intestine to the small intestine further down so that the stomach acids and digestive enzymes from the bypassed stomach and first portion of small intestine will eventually mix with the food.

The gastric bypass works by several mechanisms. First, similar to most bariatric procedures, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed. Additionally, because there is less digestion of food by the smaller stomach pouch, and there is a segment of small intestine that would normally absorb calories as well as nutrients that no longer has food going through it, there is probably, to some degree, less absorption of calories and nutrients. Most importantly, the rerouting of the food stream produces changes in gut hormones that promote satiety, suppress hunger, and reverse one of the primary mechanisms by which obesity induces type 2 diabetes.

  • Produces significant long-term weight loss (60 to 80 percent excess weight loss)
  • Restricts the amount of food that can be consumed.
  • May lead to conditions that increase energy expenditure.
  • Produces favorable changes in gut hormones that reduce appetite and enhance satiety.
  • Typical maintenance of >50% excess weight loss.

Am I A Candidate for Laparoscopic Gastric Bypass Surgery?

Gastric bypass surgery is not right for everyone. Here are some of the things we will consider when evaluating your candidacy for laparoscopic gastric bypass surgery.

Gastric bypass surgery is indicated for use in weight reduction for severely obese patients with a Body Mass Index (BMI) of at least 40 or a BMI of at least 35 with one or more severe co-morbid conditions, or those who are 100 lbs. or more over their estimated ideal weight.

This operation may be right for you if:

  • You are at least 18 years old.
  • Your BMI is 40 or higher, or you weigh at least twice your ideal weight, or you weigh at least 100 pounds more than your ideal weight. (BMI is calculated by dividing body weight (lbs.) by height in inches squared (in²) and multiplying that amount by 703). BMI Calculator
  • You have been overweight for more than 5 years.
  • Your serious attempts to lose weight have had only short-term success.
  • You do not have any other disease that may have caused your obesity.
  • You are prepared to make substantial changes in your eating habits and lifestyle.
  • You are willing to continue being monitored by the specialist who is treating you.
  • You do not drink alcohol in excess.
  • If you do not meet the BMI or weight criteria, you still may be considered for surgery if your BMI is at least 35 and you are suffering from serious health problems related to obesity.
  • Is technically a more complex operation than adjustable gastric band surgery [link to adjustable gastric band surgery page] or laparoscopic sleeve gastrectomy [link to laparoscopic sleeve gastrectomy page] and potentially could result in greater complication rates.
  • Can lead to long-term vitamin/mineral deficiencies, particularly deficits in vitamin B12, iron, calcium and folate.
  • Generally, has a longer hospital stay than adjustable gastric banding surgery.
  • Requires adherence to dietary recommendations, life-long vitamin/mineral supplementation, and follow-up compliance.

While gastric bypass surgery is an effective treatment for morbid obesity, the pounds do not come off by themselves. Surgery is an aid to support you in achieving lasting results by limiting food intake, reducing appetite and slowing digestion. However, your motivation and commitment to adopt a new lifestyle are extremely important for long-term weight loss. You must be committed to new eating habits for the rest of your life. Exercise is an equally important component of a changed lifestyle.

This is a permanent, non-reversible procedure.

This operation is very complex and therefore has several disadvantages in comparison to the gastric sleeve and adjustable gastric band surgeries. The stomach and lower bowel are cut, stapled and rerouted, which can result in leakage or possible stenosis or smaller opening.

Patients who eat foods that are high in fat and sugars may experience “dumping syndrome.” This is a result of the intestine not able to absorb the fatty foods. The patient will experience gastric distress such as nausea, vomiting, cramping, diarrhea and possible sweats.

Patients may also experience vitamin deficiencies of important nutrients such as vitamin D, calcium, B-complex, magnesium and iron.

Frequently Asked Questions About Gastric Bypass Surgery

Laparoscopic bypass surgery is the most commonly performed bariatric procedure. This method makes the stomach smaller and alters digestion. It is referred to as a combined restrictive and malabsorptive procedure because less food can be eaten and fewer calories can be absorbed.

Most patients recover from surgery without complications. Patients are encouraged to get out of bed and start walking by the next day. The hospital stay for patients who undergo gastric bypass surgery is usually 2–3 days. Most individuals return to work in 2–3 weeks.

Gastric bypass surgery is considered successful when a person loses 50 percent of his or her excess weight. Although few people lose all their excess weight, they do gain numerous health benefits, which may be lifesaving. It’s important to remember that there are no guarantees with any method of weight loss, even surgery. Success hinges on your ability to become part of the plan to support the surgical tool you’ve chosen and make lifestyle changes with exercise and dietary adjustments.

Yes, strenuous activity should be avoided until you are healed. Walking, however, is a required activity at this stage of recovery. You are advised not to drive if you are taking pain medication other than acetaminophen (Tylenol). At your first follow-up visit, your doctor will determine when you can return to work, but most people return to work two weeks after surgery.

Following gastric bypass surgery, you will need to follow specific eating guidelines. Our registered dietitian will work directly with you to provide dietary education before and after surgery.

Gastric bypass surgery provides two ways of weight loss: one is restriction in the amount of food that you can eat; and the other is through malabsorption. Because of this, you are required to take vitamin supplements daily especially calcium, vitamins D and B-complex, and iron. You should also follow up with your surgeon annually to have your weight checked and blood work completed to measure your essential vitamin levels.

Light exercise, such as walking, should begin immediately after surgery. Vigorous exercise will be gradually introduced in 6–8 weeks. Exercise will not only keep you feeling well and energized, but it also helps burn fat and calories. For many people, returning to physical exercise is an important step toward feeling better.

Bariatric surgery has an excellent long-term track record for helping morbidly obese individuals maintain weight loss. If you are committed to making permanent dietary and lifestyle changes, your chance of weight re-gain is minimized.

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  1. References: 1. Fisher BL, et al. Am J Surg. 2002;184:9S-16S. 2. DeMaria EJ, et al. Surg Obes Relat Dis. 2010;6:347-355. 3. Chaston TB, et al. Int J Obes. 2007;5:743-750
  2. Reference: 1. Nguyen NT, et al. Ann Surg 2009;250: 631-641