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Gastric bypass treatment at The London Clinic

Bariatric surgeons at The London Clinic are experienced in the Roux-en-Y gastric bypass (RNY). This is by far the most common of the many variations of gastric bypass operations that are performed in the world today.

What is a Roux-en-Y gastric bypass?

This is a more extensive and complex procedure than a sleeve gastrectomy. It is suitable for people with a BMI of 50 or less, as it is not safe to attempt in more obese patients.

A gastric bypass separates off a major part of the stomach, creating a small stomach pouch that reduces the amount of food you can eat.

The bypass part of the surgery then diverts the path of food after it leaves the stomach. Normally food leaves the stomach and passes through sections of small intestine that are around 6 metres long. A gastric bypass creates a new opening at the bottom of the stomach pouch, which is connected to a point further down the small intestine.

A gastric bypass therefore leads to weight loss in two ways:

  1. The small stomach pouch reduces the amount of food you can eat: this is the most important component.
  2. The bypass of some of the small intestine prevents you absorbing some of the calories and other nutrients from your food.

What does a gastric bypass involve?

The procedure can usually be performed by laparoscopic (keyhole) surgery and takes approximately one hour. It is classed as major surgery and is not straightforward to reverse. Most patients stay two nights in hospital.

You need to be prepared to work hard after your surgery to make sure that you eat the right balance of nutrients. Your ability to digest food is impaired after surgery, and you need to make sure you do not develop malnutrition.  Your eating habits will change as they do after a sleeve gastrectomy.

What results can I expect?

  • Weight loss following a gastric bypass is generally 70% of excess weight at two years. This is greater than that achieved with a gastric band or sleeve gastrectomy alone.
  • If you have type 2 diabetes this can go into remission. This can happen within a day to up to six weeks following the surgery in most patients because insulin resistance is lowered. 
  • Sustained weight loss and benefits to health then depend on your commitment to maintaining a healthy diet and taking nutritional supplements for the rest of your life.

What problems might I experience with a gastric bypass?

Major complications include:

  • Leakage at the junction between the stomach and the small intestine. General statistics show this occurs in one in 200 gastric bypass operations done in the UK though it is very rare with our experienced surgeons.
  • Formation of peptic ulcers at these joins. Generally this affects one in 100 patients. Each patient should be monitored to detect and treat ulcers promptly.
  • Internal hernias, which are extremely rare but can be serious.
  • Dumping syndrome, which is very important to patients who have a sweet tooth. If you have a gastric bypass and you eat high-sugar food, the sugar rush directly into the lower part of the small intestine makes you feel light-headed and queasy. This happens because you produce a spike of insulin to deal with the sugar. The feeling that you get with dumping syndrome is so unpleasant that your brain is re-programmed to avoid sweet foods.

Private treatment at The London Clinic

For more information about a private gastric bypass treatment at The London Clinic call  +44 (0) 020 7616 7693.

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