Prof. Dr. Emin Ersoy General Surgery
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Surgical Methods

Gastric Sleeve Surgery

About 80% of the stomach is removed by keyhole surgery, leaving a narrow tube that holds less food and makes less hunger hormone.

BMI 40+ · 35-40 with related conditions

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Overview of gastric sleeve surgery

Gastric sleeve surgery (sleeve gastrectomy) is a weight-loss operation in which about 80% of the stomach is removed and the rest is shaped into a narrow tube. It is one type of weight-loss (bariatric) surgery and may be considered for people who have not been able to lose enough excess weight through changes to diet and exercise. Because the smaller stomach holds less food, the aim of the operation is to reduce the amount you can eat.

During the operation, the stomach is shaped into a narrow tube, roughly the shape of a banana, starting near its outlet (the pylorus) and running up to the oesophagus (food pipe). The remaining stomach still does its job of digesting food, and food still passes along the usual route into the small intestine. The part that is removed is also where the hunger hormone ghrelin is made, so less of this hormone is released after the operation. The operation therefore works in two ways: the stomach holds less, and the signal that drives hunger is weaker.

Because part of the stomach is removed, a gastric sleeve cannot be reversed. This is one of the reasons why the decision is made carefully, after a full assessment. If you would like to compare it with an operation that also reroutes the intestine, see the gastric bypass page.

Who is it for?

As with all types of bariatric surgery, careful selection of patients is essential, and a gastric sleeve is not suitable for everyone. It is usually considered if you have:

  • a BMI (body mass index) above 40 kg/m², or
  • a BMI between 35 and 39.9 kg/m² together with serious obesity-related conditions, or
  • a BMI above 30 kg/m² with type 2 diabetes or severe metabolic problems.

Meeting these figures is only part of the picture. The operation divides life into a before and an after, so you also need to be willing to keep to a healthy lifestyle for the long term. This means changing how and what you eat, taking vitamin supplements regularly and attending your follow-up. Whether a gastric sleeve is the right option for you is decided after your medical assessment, taking into account your health, your eating habits and your own wishes.

Risks

Gastric sleeve surgery is a major operation, and like any operation it carries risks. General risks of keyhole surgery on the abdomen include bleeding, infection of a wound or inside the abdomen, reactions to the anaesthetic and blood clots in the legs or lungs.

There are also risks linked to this particular operation:

  • a leak from the line where the stomach has been stapled and closed, which may need further treatment
  • heartburn or reflux, which can start or get worse after the operation
  • a lack of vitamins and minerals if supplements are not taken regularly, which can show up as problems such as hair loss, poor sleep and tiredness

Your surgical team will explain these risks to you in detail before you give your consent, and the precautions described below, such as getting up and moving early and taking a multivitamin, help to reduce some of them.

Preparation

Preparation for a gastric sleeve starts well before the day of the operation. It usually includes a thorough medical assessment to check that the operation is suitable for you, blood tests and other tests if needed, and advice from a dietitian about eating before and after surgery. Depending on your health, you may also be seen by other specialists, and a psychological assessment may be offered to help judge how well you are likely to adjust to the changes after the operation.

Before the operation, your medicines are reviewed with you. Blood-thinning medicines and some other medicines may need to be stopped for a while, and you will be told which ones to keep taking. You will be asked not to eat or drink for a set time before the operation. If you smoke or drink alcohol, stopping before surgery helps your recovery, and it is a good idea to arrange some help at home for the first days. Finally, the possible risks and benefits are discussed with you and you give your written consent.

What happens

On the day

The operation is done by keyhole (laparoscopic) surgery, under general anaesthesia, so you are asleep throughout. The surgeon works through several small cuts in the upper abdomen, watching an enlarged image from a small camera on a screen. Using special instruments, the stomach is divided along its length, the larger outer part is removed through one of the small cuts, and the remaining stomach is closed to form the narrow tube.

Because the operation is done through small cuts rather than one large one, you can usually get out of bed and start walking soon afterwards. Moving early helps your recovery and lowers the risk of blood clots.

Aftercare

After the operation, your diet is built up in stages. In the first weeks you have fluids, following the plan your team gives you, and then you move on step by step to puréed, soft and finally solid food. Throughout this time, two things matter most: getting enough protein and taking your vitamins.

Protein comes first

From the very first day, getting enough protein is the main priority. Protein is the foundation of your diet after bariatric surgery. To help prevent loss of muscle while you are losing weight, you should have at least 60 g of protein a day. You will also need to take a multivitamin regularly, because this helps to prevent problems such as hair loss, poor sleep and tiredness.

Building up your diet in stages

  • From week 3: puréed food. You can eat any food as long as it is blended to a purée. Keep your protein intake at 60 to 80 g a day and drink enough fluids.
  • Week 4: soft food. In this stage you get used to chewing very thoroughly and eating slowly. Do not eat and drink at the same time.
  • Week 5: moving on to solid food. Lean protein and vegetables are now important. Continue to keep solid food and drinks apart. You will be told which foods to avoid.

The habits you learn in these weeks, such as eating slowly, chewing well and keeping food and drinks apart, are meant to stay with you in the long term. As part of your follow-up, a routine blood test check is done at 6 months.

When should you contact your doctor?

After you go home, contact your doctor or the hospital straight away if you notice any of the following:

  • a high temperature or shivering (chills)
  • increasing pain or swelling in the abdomen
  • nausea or vomiting that does not stop
  • being unable to drink enough fluids
  • redness, swelling or fluid leaking from any of the cuts
  • shortness of breath or a persistent cough
  • swelling of the calf or tenderness in the leg

Frequently asked questions

How much of the stomach is removed in gastric sleeve surgery?

About 80% of the stomach is removed. The rest is shaped into a narrow tube, roughly the shape of a banana, that still digests food.

Who can have a gastric sleeve?

It is usually considered if your BMI is above 40 kg/m², between 35 and 39.9 kg/m² with serious obesity-related conditions, or above 30 kg/m² with type 2 diabetes or severe metabolic problems. You also need to be willing to keep to a healthy lifestyle for the long term.

Is a gastric sleeve done by keyhole surgery?

Yes. The operation is done by keyhole (laparoscopic) surgery under general anaesthesia, through several small cuts in the upper abdomen.

Can a gastric sleeve be reversed?

No. Because part of the stomach is removed, the operation cannot be reversed.

What can I eat after a gastric sleeve?

Your diet is built up in stages: puréed food from week 3, soft food in week 4 and solid food from week 5. Throughout, you should keep food and drinks apart.

How much protein do I need after the operation?

You should have at least 60 g of protein a day, and 60 to 80 g a day during the purée stage. You also need to take a multivitamin regularly.

Would you like to discuss this?

The right method for you is decided together after examination and tests. You can start with the pre-assessment or call directly.

Request an appointment +90 533 300 35 75

Other methods in this group

Gastric Bypass Surgery A walnut-sized stomach pouch is joined straight to the small intestine, so you eat less and absorb fewer calories and less fat. BMI 40+ · 35-40 with e.g. type 2 diabetes Learn more › Bariatric Surgery Keyhole operations on the stomach and small intestine, such as the gastric bypass, for severe obesity that other treatments have not helped. Severe obesity · other treatments failed Learn more › Diabetes Surgery Keyhole operations on the stomach and small intestine that act through gut hormones such as GLP-1 in type 2 diabetes. BMI 30+ with type 2 diabetes Learn more ›

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