A sleeve gastrectomy reduces the size of the stomach by permanently removing about 75 % of its volume. The stomach is divided vertically from top to bottom leaving either a pyramidal or a banana shaped stomach that empties into the small intestine, which remains intact.

What is a sleeve gastrectomy?

Also known as a partial gastrectomy, vertical gastrectomy or gastric sleeve, this type of weight loss surgery removes part of the stomach but leaves the way food passes through the stomach unchanged. The body of the stomach is divided vertically, and the part of the stomach that remains has the cardiac sphincter valve at the top and the pyloric sphincter that leads to the small intestine at the bottom.

A sleeve gastrectomy leads to a loss of appetite as the part of the stomach removed takes away the production of a hormone that stimulates appetite. The surgery also restricts the amount of food you can eat in one go.

You will find that you will not be hungry and can only eat small meals at first. If you use this opportunity to change your eating habits, this will continue. You will lose weight only if you also work hard on controlling your food intake, on eating healthier meals and on doing regular exercise as time goes on.

Your reduced stomach can stretch if you constantly force it to accept larger meals, although it can never regain its previous size.

Having a sleeve gastrectomy

This is a major surgical procedure that requires a general anaesthetic. The operation is virtually always done laparoscopically, using keyhole surgery and you will normally need to stay in hospital for two days. Recovery time is a little longer than that after a gastric band but most patients resume normal activities in two weeks.

What are the benefits of a sleeve gastrectomy?

The main advantage of a sleeve gastrectomy is that it does not change the way your body digests food, so there is less chance of you becoming deficient in key vitamins, minerals or protein with time, though you need to take supplements in the first two years as your food intake will be severely reduced.

Patients who have had this type of weight loss surgery feel fuller sooner, even though they can eat normally. In the first 6-12 months, there is no appetite because of a lack of the appetite-causing hormone. Weight loss is comparable with a gastric bypass in the first 24 months.

The sleeve gastrectomy in very obese patients

When we treat patients who are morbidly obese, with a BMI of 60 or higher, we use the sleeve gastrectomy as the first stage in a potentially two-stage weight loss treatment. The sleeve gastrectomy is the less risky of the two operations and can be done safely in people who are so obese.

In such patients, the tendency to over-eat is strong and the stomach is liable to expand after one to two years. However, the sleeve gastrectomy is able to bring about enough weight loss to bring their BMI down to around 50, which then makes it possible to perform a duodenal switch. This more complex surgery cannot be attempted in someone with a higher BMI.

What results can I expect from a sleeve gastrectomy?

Most patients lose 60–70 % of their excess weight in the first 12 months after a sleeve gastrectomy operation. If it is done as a two stage operation, you may lose 30-50% of your excess weight. The timing of the second stage operation, the duodenal switch, ranges from 12–24 months after the first, depending on the lack of further weight loss or even the tendency to gain weight.

Not all patients who start off with a very high BMI will need the second stage operation; if motivation is high and patients continue to lose weight 2-3 years after a sleeve gastrectomy, they can opt to defer the second operation indefinitely.

What problems might I experience with a sleeve gastrectomy?

The most serious complications include rupture of the stomach along the line at which the stomach has been stapled. Bleeding and leakage can occur within 24-48 hours after surgery. Data shows that this occurs in fewer than one in 100 patients. However, the skill of the bariatric surgeon is crucial; the very experienced surgeons at The London Clinic rarely see such complications.

Although many patients do lose weight after a sleeve gastrectomy, the impact of the surgery can diminish over time. If you eat larger meals, this will stretch the remaining stomach pouch and a ‘pyramidal’ stomach expands more easily compared to a ‘banana’ stomach.