Gastric Bypass Surgery

The Roux-en-y Gastric Bypass procedure is a restrictive and malabsorptive procedure. Gastric bypass involves partitioning the stomach so that swallowed food quickly fills a very small stomach "pouch." This pouch is designed to initially hold less than an ounce. A segment of the small intestine is then connected to this small pouch through a very small opening in an arrangement that surgeons have termed "Roux-en-y."

These surgical changes physically restrict food intake and limit the sensation of hunger. Food fills the small pouch quickly and stretches the walls. Stretch receptors in the walls send a signal to the brain to turn off the hunger sensation. The very small opening between the stomach pouch and the small intestine limits how fast the pouch can empty. Thus, you feel full after eating only a small amount of food or liquid and you stay full longer. Finally, the connection of the small intestine to the pouch can prevent the digestion of certain high-caloric (carbohydrate) foods.

Gastric bypass surgery is the popular weight loss surgery in the United States, according to the American Society for Bariatric Surgery and the National Institutes of Health. Many, if not most, gastric bypass surgeries are performed using a minimally invasive, or laparoscopic, procedure. In comparison to traditional open procedures, this approach provides less pain and discomfort, quicker recovery, and less scarring than traditional open procedures. It also decreases the chances of some complications.

Effectiveness of Surgery

The effectiveness of gastric bypass surgery depends upon many factors, including participation in pre-operative and post-operative education programs, ongoing support, age and the sex of the patient. The most important success factor is the patient’s commitment to follow recommended guidelines, incorporate healthy eating habits (high-protein, low-sugar and low-fat diet) and exercise. 

In addition to eating a nutritious diet, patients need to space meals properly. For gastric bypass surgery patients, the small pouch and the rearrangement of the bowel make this easier because it helps eliminate hunger pangs and places a limit on the amount that can be eaten at one time. Surgeries are considered successful when patients lose 40 percent or more of their excess weight. 

Having a full complement of professionals, including board certified surgeons, registered nurses, nurse practitioners, physician assistants, registered dieticians and experienced support staff is critical. A comprehensive program includes all of these disciplines. 

In terms of weight loss, depending on the factors above, most people (around 90 percent), will lose between 50 and 80 percent of their excess body weight. For someone weighing 350 pounds, with an ideal body weight of 150 pounds, this is equal to a loss of 100 to 160 pounds. Most of the weight loss occurs in the first six months; people usually reach a stable weight within 18 to 24 months.

According to our patient data: 

  • Average best weight loss for patients undergoing laparoscopic gastric bypass surgery is 75 percent. 
  • All patients who have undergone gastric bypass surgery have lost weight.
  • Two years after gastric bypass surgery, 98 percent of patients have lost more than 50 percent of excess weight with an average of 75 percent of excess weight. 

Often the greatest benefit of gastric bypass surgery is in reducing the impact of coexisting diseases, and sometimes curing them altogether. For example, 80 to 90 percent of type II diabetics no longer need medication (within days to months) after this operation. Acid reflux is usually cured. Cholesterol levels come down to the normal range. Dependence on blood pressure medication often vanishes. As weight is lost, there is less force on damaged joints, causing much less pain and better mobility. Women with fertility problems may return to a normal ovulation cycle and become pregnant. And, minimized obstruction in the airways often cures sleep apnea.

Is Gastric Bypass Surgery Reversible?

No. Gastric bypass surgery should be considered permanent.

Risks and Disadvantages of Gastric Bypass Surgery 

  • Cutting and stapling of stomach and bowel is required
  • More operative complications than with the gastric band
  • A portion of digestive track is bypassed, reducing absorption of essential nutrients
  • Complications due to malabsorption reported
  • It is not adjustable
  • Higher mortality rate than the gastric band

Why do some patients regain weight they lost after Roux-en-y Gastric Bypass?

Patients are encouraged to think of this operation as providing a tool for their use. If used incorrectly or not at all, the weight will return. In other words, the pouch can be "beaten." While we cannot predict who will regain weight, we can usually ascertain the reason once the regain is identified.

The small pouch created during the operation will gradually enlarge over time. (There are some habits that can cause this to happen sooner than necessary, and to a greater degree than expected, but most of these are prevented with the dietary instructions you will receive from the program.) Nevertheless, as it enlarges, it becomes able to hold more food. As the opening into the small intestine enlarges, the pouch empties faster. Faster emptying, plus a larger pouch, equals the sensation of hunger returning.

We expect that during the first two years of the pouch's use, a patient undergoes a fundamental change in his/her approach to eating. Once these healthy eating habits are learned, most people use them for life and can control their weight forever, even if increased hunger occurs. Even in patients that regain weight, a return to healthy eating habits and effective use of the pouch as a weight loss tool allow them to reclaim control.