How does Weight Loss Surgery Work?
The simple answer is we don’t know. We once thought it was purely mechanical – small stomach, eat less, or short intestine, absorb less – but this is not the case. We now believe that our bariatric procedures work through a complex change in the hormonal response to food. This appears to be the same mechanism by which diabetes and other metabolic problems respond so quickly to surgery before weight loss occurs. The exciting part of this research is that one day, we may be able to make surgery for this problem obsolete, once we identify the reason why bariatic surgery works so well, whereas non-surgical treatment does not.
Fresno Heart & Surgical Hospital currently performs various types of weight loss surgery:
Roux-en-Y Gastric Bypass
The Roux-en-Y Gastric Bypass (RGB) is the oldest and most common type of weight loss or bariatrics surgery. This technique has been performed around the world for nearly 50 years, long enough for the medical community to study its long-term risks and benefits. Here's what the procedure entails:
1. Surgeons create a very small incision in the abdomen. Specialized instruments, including a camera, are guided through this tiny incision to perform the operation. This minimally invasive approach is known as laparoscopic surgery. By eliminating the large incision associated with traditional surgery, patients often experience shorter recovery times and are less susceptible to infection.
2. A small pouch about the size of a thumb is created at the top of the stomach using surgical staples. This pouch becomes the patient’s new stomach.
3. This new, smaller stomach is connected directly to the middle portion of the small intestine, bypassing the rest of the stomach and the upper portion of the small intestine. None of these bypassed organs are harmed or removed. See Surgery Animation
This technique is a proven way for patients to achieve and sustain weight loss. Patients will often continue losing weight at a steady rate up to two years after surgery or until they have reached a healthier weight.
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Adjustable Gastric Band
The adjustable gastric band, is a device that is placed on the upper portion of the stomach. Like gastric bypass, the gastric band procedure is done laparoscopically with minimal incisions.
The gastric band creates a feeling of fullness with less food. Additionally, the adjustable band does not require stapling nor the removal of the stomach or intestine.
Weight loss is not as rapid as with the gastric bypass, but can be just as sustainable. See Surgery Animation
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Sleeve Gastrectomy
In a Sleeve Gastrectomy the stomach is greatly reduced by removing most of it and stapling closed the remaining portion. What's left of the stomach resembles a slim banana and is a tenth of its original size. Food intake is drastically limited, but absorption of nutrients in the small intestine is unaffected. See Surgery Animation
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Biliopancreatic diversion
Biliopancreatic diversion (BPD) is a malabsorptive procedure, meaning it works to switch on weight loss by limiting how much food can be put in the stomach and resricting how much calories and nutrients the body absorbs. Biliopanceatic diversion involves rearranging the small intestine to make the functional part shorter and less efficient. During a BPD procedure approximately 75% of the stomach is removed to restrict food intake and reduce acid output. Then the small intestine is divided, attaching one end to the stomach pouch to create an alimentary limb where the food moves through with little absorption.
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Duodenal switch
Biliopancreatic diversion with duodenal switch (BPD/DS) is very similar to gastric bypass. Instead of a small stomach pouch, the surgeon creates a sleeve-shaped stomach. The surgeon then attaches the final section of the small intestine to the stomach sleeve. The small intestine absorbs calories and nutrients. So, bypassing all but the last section of the small intestine ensures that far fewer calories are absorbed.
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Revisionary Procedures
You might be interested in a revisionary procedure for several reasons. Some patients fail to lose as much weight as they would like or need 
to, while others may be gaining weight back again. As the disease of obesity is incurable, it would be unreasonable to expect one intervention to solve this problem for all patients. Likewise, if the disease is only partially treated, then you may be a candidate for further intervention depending on your risk/benefit ratio.
Some patients may be experiencing complications of the primary operation such as diarrhea, malnutrition, unexplained abdominal pain, or ulcers. Many times, with the proper treatment and follow-up, we can avoid another operation. But if its necessary, we can perform revisionary procedures laparoscopically, even if your first operation was done open, with a large incision.
Revisionary procedures are complex and highly individualized. The risks are much greater than a primary operation, but the benefits could be much greater as well. Not every bariatric surgeon feels comfortable or has the experience to perform revisionary surgery. Certainly, the average general surgeon should not attempt revisionary bariatric surgery, except in an emergency.
Endoscopic / Endoluminal / Single-incision / Incisionless / NOTES
There are many bariatric procedures in development, experimental or investigational, that have caught the interest of entrepreneurs and patients. Because of our dedication to bring forth the most effective and safest treatment options available and our reputation for quality, we are approached and have access to many devices and techniques not available to the general public. However, our ethics will not allow for human experimentation, or advising ineffectual treatment just for financial gain. There is a difference between state-of-the-art and trendy. The test for us is: “Is that what you would advise a member of your own family?” back to top
