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Gastric bypass surgery

Gastric bypass surgery is a weight loss surgery procedure that restricts the amount of food you can eat and reduces the amount of calories absorbed.

What is gastric bypass surgery? 

Gastric bypass surgery is a weight loss surgery procedure that restricts the amount of food you can eat and reduces the amount of calories absorbed. 

  • This surgery is designed to help very overweight people achieve substantial and long-term weight loss.
  • It is a more effective and less risky procedure than stomach stapling, which used to be carried out. 
  • It is a major surgical procedure that carries greater risks of complications than gastric banding. The procedure isn’t easily reversible. For more information, speak to your consultant.

What happens during the gastric bypass surgery?

A stapler is used to divide the stomach into two parts. This creates a smaller pouch at the top, taking in less food to make you feel full. Instead of the food then passing into your stomach through the band (as is the case with gastric banding), food bypasses the stomach and much of the intestine through a small intestine that has been rerouted and grafted onto the small stomach pouch.

What is the recovery like?

You should be able to go home three to six days after the gastric bypass surgery operation. Most people need six weeks to recover after the operation. You will need to attend follow-up appointments with your doctor, dietician and patient support groups.

On average, people lose around 70 per cent of their excess weight within two years of gastric bypass surgery. Average actual weight loss is around one stone per month, though this varies with each patient. These figures are a guide. For further information, speak to your consultant. After the gastric bypass operation, you will need to take nutritional supplements permanently.

Does this surgery always lead to major weight loss?

This surgery is designed to help patients lose substantial amounts of weight. However, as with all medical procedures, there is no guarantee that it will lead to the desired results.  

The following lifestyle changes can help make the procedure a success:

  • Giving up smoking
  • Eating a healthy and balanced diet
  • Exercising regularly. Your GP can recommend exercises.

Possible complications

As with all major surgeries, there are some potential risks. These can include*:

  • Lung problems
  • Spleen injury
  • Anastomotic leakage
  • Bleeding after surgery
  • Wound infections
  • Blood clots
  • Blockages

Some patients find that after a year or two of rapid weight loss, they are left with excess skin.

*This is not a definitive list and symptoms will vary with each patient. Please ask your consultant for more information.

Gastric bypass surgery from Circle Health

The procedure can be carried out using keyhole surgery, through five or six small cuts. It can also be carried out as an open operation with one vertical cut in the abdomen. Your consultant will discuss which is more appropriate for you. For more information, and if you have any queries about the procedure, speak to your consultant. 

Specialists offering Gastric bypass surgery

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Mr John Loy

Consultant Upper GI and Bariatric Surgeon

MB BCh FRCSEd (Gen Surg)

The London Independent Hospital

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Mr Sanjay Agrawal

Consultant Bariatric & Upper GI Surgeon

MB BS, MS, FRCSEd, FRCSGlasg, FRCS (Gen. Surg)

The London Independent Hospital

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Mr Abdulzahra Hussain

Upper GI/Bariatric

MBCHB, FRCSEng, FRCSI, FRCS(GS), FEBS(Gen.Surg), FICMS(Gen.Surg)

The Blackheath Hospital 1 more Chelsfield Park Hospital

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Mr Bilal Alkhaffaf

Consultant Upper GI and Bariatric Surgeon

MBChB, PhD, FRCS

The Alexandra Hospital

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Mr Alan Li

Consultant Upper GI, Bariatric and General Surgeon

MbChB, FRCS (Eng), FRCS (Ed), FRCS (Gen Surg)

The Alexandra Hospital

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Mr Shay Nanthakumaran

Consultant Upper Gastrointestinal, Bariatric and Laparoscopic Surgeon

MB ChB, MD, FRCS Ed

Albyn Hospital

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