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Roux-En-Y Gastric Bypass

What is a Roux-En-Y Gastric Bypass?

Often referred to as a 'RYGB' procedure, or simply as a 'gastric bypass', this procedure (as the name implies) involves changing the path of ingested food in the gatrointestinal tract so that it bypasses the stomach and the upper small intestine, and then reconnects with the small intestine at a point approximately a metre's length away from the stomach.

Gastric bypass is regarded as the 'benchmark' bariatric procedure.

How does it work?

By diverting ingested food away from a large section of the gastrointestinal tract, nutrients can only be absorbed by a much smaller section of the gut, which then results in gradual weight loss.

What are the advantages of this approach over other bariatric procedures?

  • The procedure can in some cases be reversed.
  • Less chance of patient experiencing reflux after the procedure.
  • It is the most successful bariatric procedure from the point-of-view of long-term result.
  • It ss the safest and most appropriate treatment for patients who have undergone gastric banding which as not resulted in weight loss.
  • Metabolic changes after a gastric bypass are beneficial to patients with insulin resistant diabetes.

How successful is it?

A successful long-term outcome after a gastric bypass procedure depends on the patient fully adopting a new approach to living including dietary and exercise changes. If the patient is unable or unwilling to make these changes the procedure may not result on long-term weight loss.

Where the necessary changes are adopted, patients can expect to lose around 60% of their excess weight.

How should I prepare for the procedure?


Being an active smoker greatly increases the risk of poor wound healing and breakdown of wounds after the procedure. For this reason, we recommend you give up smoking entirely. Dr Silverman will only treat a non-smoking patient.


If you are taking an anti-inflammatory medication or Warfarin, Aspirin of Plavix you must stop taking these one week before the procedure. Please contact Dr Silverman if you have any questions relating to your current medication.

You will receive any further specific instructions on how to prepare for your procedure from Dr Silverman well ahead of the date of the procedure.

What is involved in the procedure?

A roux-en-y gastric bypass involves the creation of a small pouch from the upper part of the stomach. This pouch has a capacity of around 15ml – much smaller than a normal adult stomach which has a capacity of roughly 1500ml (1.5l).

Once the pouch has been formed, the jejunum - the middle section of the small intestine is divided into two. The upper section of the jejunum is joined to the newly formed pouch and the lower section is then attached around one metre further down the small intestine.

The procedure is performed under a general anaesthetic and can take anything from one to four hours, depending on whether the procedure is carried out using laparoscopic surgery or conventional open surgery.

A laparoscopic procedure is generally much shorter than a conventional procedure. Most gastric bypass procedures are performed laparoscopically, although some patients who have previously undergone abdominal surgery may need to undergo conventional surgery.

Recovery Guidance

Hospital stay

It is usual for gastric bypass patients to stay in hospital for two or three days after the procedure.

Returning to normal activities

It is common to feel some weakness and fatigue for a few days after the procedure.

After a gastric bypass, patients will need to adopt a different approach to diet and exercise as well as taking nutritional supplements on an ongoing daily basis. Dr Silverman and her team will be able to give specific guidance on diet and exercise for each individual patient.

Risks / complications

There are risks associated with all surgical procedures, such as wound infection, and risks relating to anaesthesia and bleeding during the procedure.

The risks/complications specific to gastric bypass after the procedure include:

  • Wound infection.
  • Staple line leak.
  • Blood clot (thrombosis).
  • Stricture (inflammation / blockage of the stomach opening).

Longer term the following conditions may develop:

  • Nutritional deficiencies.
  • Gallstones.
  • GORD.

Dr Silverman will be able to discuss any possible risks or complications with you well ahead of the procedure.