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Bariatric Surgery

Gastric Bypass Surgery


Gastric bypass illustration

What is Gastric Bypass Surgery?

Gastric bypass surgery, the most common bariatric surgery in the United States, is the "gold standard" in weight-loss surgery. Patients typically lose 70 to 80 percent of their excess body weight.

Most gastric bypass surgeries are performed laparoscopically through several small incisions under general anesthesia. Surgery time is approximately two hours (times vary depending on the health of the patient and specifics of their procedure).

How Gastric Bypass Surgery Works

So what is gastric bypass surgery and how does it work? The procedure involves creating a small pouch, which reduces the stomach from the size of a cantaloupe to the size of an egg. Once the stomach has been reduced it is then attached to the middle of the small intestine, bypassing the section of the small intestine (duodenum), which limits the amount of calories and nutrients the body can absorb.

Ultimately, patients eat less because the stomach is smaller and they absorb fewer calories because food doesn't travel through the duodenum.

Patients must drastically alter their diet after gastric bypass surgery in order to achieve long-term weight-loss results. A common side effect from dietary non-compliance is dumping syndrome, which is the body's reaction to an intolerance of refined sugar. Dumping syndrome (rapid gastric emptying) is a condition that happens when undigested food empties into the small intestine too quickly. Symptoms can include nausea, cramping, diarrhea and/or vomiting. To learn more, visit the National Institute of Diabetes and Digestive and Kidney Diseases (NIH). This side effect can give patients extra motivation to avoid such foods, further escalating weight-loss efforts.

What Are The Exclusions for Gastric Bypass Surgery?

Certain conditions can exclude a patient from being a candidate for gastric bypass surgery, including:

  • Severe cirrhosis of the liver
  • Smoking (patient must be tobacco-free for one month prior to surgery)
  • Mental condition causing non-compliance
  • Untreated psychological disorders
  • Current alcohol or substance abuse.

If you'd like to learn more about Bariatric Center of the Rockies and/or gastric bypass surgery, please request an appointment with our bariatric patient navigator.


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