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Catriona asked...

Gastric sleeve and a gastric bypass

What is the main difference between a gastric sleeve and a gastric bypass operation? I've been offered both - which one should I go for?

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The answer

Gastric Surgery is considered when an individual has a Body Mass Index (BMI) above 40 or above 35 with the addition of diabetes type 2 or other significant medical concern. A BMI of this level is considered potentially life threatening so this may be offered to help reduce the risks to you, particularly when you have attempted to adjust your lifestyle and lose weight through diet and exercise too.

Gastric surgery has been proven to  be effective and,  significantly reduces weight and excessive body fat.

It should also be noted that following this type of surgery that is important to maintain a healthy lifestyle and balanced diet.

There are different types of weight loss surgery available but the most common surgeries offered are: Gastric Banding, Gastric Bypass and the Gastric Sleeve.

All the above procedures are done under General Anaesthetic and are usually done by Laparoscopic measures unless otherwise medically  indicated.

Gastric Banding-

This involves the placing of a band around the top of your  stomach , therefore dividing the stomach into two sections.
This band can be adjusted over a period of time to allow the pouch sizes to be adjusted according to weight loss requirements.

By creating a small pouch at the top of the stomach it means that only small amounts of food need to be eaten before the individual feels full. This is the only type of gastric surgery that is reversible. This procedure takes roughly one hour to complete. This procedure allows up to 50% of the body weight to be lost and in a gradual period of time.

Gastric Bypass-

This procedure involves the making of a small pouch within the stomach which is then connected to the small intestine. By creating a pouch it means that only a small amount of food can be eaten before you feel full. As the pouch is connected directly to the intestine this means that food  will not be digested in the same way and therefore not as many nutrients or calories will be absorbed. The procedure can take about 90 mins to complete. Roughly 75% of body weight will be lost.
It is more effective for weight loss in individuals with Type 2 diabetes.

This procedure has been the most common surgery to be offered for weight control but does involve more complex surgical techniques than the sleeve and banding.

Due to the way absorption of nutrients occurs it is possible for minerals and vitamins to be deficient in the body so supplements of vitamins, minerals and other nutrients may be required on a long term basis.

If food is too rich or eaten too quickly it may cause the stomach  to empty too quickly which can lead to individuals feeling very sick and weak- known as dumping syndrome.This is a permanent procedure.

Gastric Sleeve-

This procedure involves the removal of part of the stomach., particularly the part where the appetite hormone is present.
By removing part of the stomach appetite and amount of food able to be eaten is reduced. The procedure takes roughly 60mins to complete. Individuals can lose between 50-75% of their body weight. People are less likely to suffer from malnutrition and the dumping syndrome. It is a new but effective procedure.

As with all surgery there are side effects to be expected and therefore you should be  warned of risks  such as infection, bleeding and  blood clots (DVTs) as well as psychological and physical factors following the procedure.

It is extremely important to discuss with your surgeon the reason for treatment and the pros and cons to each method. Your surgeon should be able to advise you as to which method is likely to be best for you and to ensure that side effects and long term requirements  are addressed too.

We suggest that before you make your final decision that you make sure that any questions and concerns you have are fully addressed before you sign any consent forms.  Taking a list of questions with you to your consultation may help you ensure that all questions get answered fully.

Some useful information sites that may be informative in your decision making are:




Answered by the Health at Hand nurses  

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