Explainer

Can Bariatric Surgery Be Reversed?

Yes—but should it be?

When is it OK to undo bariatric surgery?

Increasing numbers of adolescents are receiving bariatric surgery as a treatment for obesity, according to a New York Times report from last week. The article points out that teenagers “are still immature, both emotionally and physically,” and potential patients must “undergo months of counseling to make sure they understand that their digestive systems are about to change, and so must their diets—forever.” Can a gastric bypass or laparoscopic banding ever be reversed?

Yes, but it’s dangerous and impractical to do so. Neither procedure ends with the removal of any parts from the body, so they can both be undone, at least in theory. But going back to reoperate on tissue that’s already been subjected to surgery increases the risks of bleeding and damage to the structures being repaired. (That’s over and above the dangers associated with any surgery—like blood clots, infection, and injury to adjacent organs.) Scar tissue from previous work makes it harder for surgeons to see and access the normal tissue. Getting suture lines or staple lines to heal properly after a repeat operation is a challenge as well.

There are some more specific reasons why it’s not a good idea to reverse a bariatric surgery. A patient who undergoes a gastric bypass may never be able to regain a fully functional digestive tract. In the original operation, doctors divide the stomach and cordon off most of its volume with staples or a plastic band; they also reroute the stomach, connecting it to the middle of the small intestine so that fewer calories can be absorbed. To reverse all this later, surgeons must divide the stomach and intestine where they had been sewn together and then rejoin them in the original spot with a surgical stapling device. But the restored configuration won’t be exactly the same as it was before the bypass. For one thing, it’s impossible to mend several nerves that help with normal gastric function. As a result of these permanent changes, a patient who chooses to undo his bypass may experience post-op gastroesophageal reflux disease.

It’s much easier to reverse a laparoscopic banding operation, but doctors rarely do so. In this procedure, an inflatable device is wrapped around the stomach, sewn in place, and then filled with saline so as to compress the space inside the organ. Taking out the band doesn’t involve the reconnection of any detached organs. If there’s any scarring around the band, though, it will be more difficult to remove the sutures and slide it off.

Surgical risks aside, doctors strongly caution patients against ever reversing their bariatric surgeries because almost all of those who do so gain back most of the weight they lost. Weight regain is a possibility even if bariatric surgeries aren’t reversed: If someone who gets a gastric bypass or lap band isn’t careful, her stomach can stretch out to accommodate more food. Studies show that most bariatric patients do lose a significant amount of weight (PDF) and keep it off for up to 10 years, although longer-term results are less certain.

Most surgeons will reverse a bariatric surgery only if the patient experiences significant complications. These might include infection, a hernia along the original incision, or a leaky stomach that, having been punctured during surgery, spills digestive acid into the abdomen or the intestine. Malnutrition is also a possibility for gastric bypass recipients if the patient isn’t careful about how she eats, since a portion of her small intestine is no longer in service. Bands carry fewer risks because they’re less invasive, but they can still erode or become infected—and patients with bands lose weight more slowly than those with gastric bypass.

According to a 2005 meta-analysis of surgical obesity treatments from Annals of Internal Medicine, between 2 percent and 4.6 percent of bariatric patients experience some form of surgical complication like bleeding or a leaky stomach or intestine—complications that could make a second operation necessary. Between 0.3 percent and 1 percent of bariatric patients die as a result of the surgery. Doctors still don’t know how the risks associated with gastric bypass and gastric banding procedures might differ in adolescents as compared with adults. A study of adolescent bariatric surgery conducted by the Cincinnati Children’s Hospital should have some conclusive results later this year.

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Explainer thanks Jeffrey Zitsman of New York-Presbyterian Morgan Stanley Children’s Hospital, Mary Brandt of Texas Children’s Hospital, and Marc Michalsky of the Center for Healthy Weight and Nutrition at Nationwide Children’s Hospital.

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