Gastric Sleeve Surgery

Gastric sleeve surgery (sleeve gastrectomy) is a weight-loss operation in which about 75–80 percent of the stomach is removed through keyhole surgery, leaving a narrow tube-shaped stomach that both reduces how much you can eat and affects hunger hormones.

Overview

The gastric sleeve is the most commonly performed weight-loss operation in the world. The intestines are not touched; only the part of the stomach along its outer curve is removed, leaving a narrow, banana-shaped stomach.

Because the stomach is smaller, a small amount of food is enough to feel full. The removed section also produces most of ghrelin, known as the hunger hormone, so appetite usually drops noticeably after surgery.

A gastric sleeve is not a shortcut to weight loss but the start of a lifelong routine of nutrition and follow-up. Whether it is right for you is assessed together with your body mass index, related conditions and a thorough work-up.

Keyhole operation that leaves the intestines untouched
Reduces stomach volume and also lowers the hunger hormone
Comprehensive health assessment before surgery
Step-by-step nutrition with a dietitian and long-term follow-up

What Is Gastric Sleeve Surgery?

In gastric sleeve surgery, also called sleeve gastrectomy, about 75–80 percent of the stomach is removed along its outer curve using special cutting and sealing devices (staplers). The remaining stomach becomes a narrow tube that continues on from the oesophagus.

The operation is restrictive: it limits how much you can eat at one meal. The change in hunger and fullness hormones can also help blood sugar control. The removed part of the stomach cannot be put back, so the operation is considered irreversible.

Who Is a Candidate for Gastric Sleeve Surgery?

People with a body mass index (BMI) of 40 or above
People with a BMI of 35 or above who have an obesity-related condition such as type 2 diabetes, high blood pressure, sleep apnoea or joint problems
People who have not achieved lasting weight loss despite diet, exercise and supervised treatment
People who are ready to follow the post-operative nutrition rules and long-term check-ups

Current international guidelines also consider lower BMI values in some people with metabolic disease. Eligibility is not decided by a single number but together with overall health, age and a psychological assessment.

In people with severe reflux, a gastric sleeve can make reflux worse, so another method such as gastric bypass may be more suitable.

Pre-operative Assessment

Obesity surgery is a team effort. Before the decision to operate, you are assessed by a general surgeon, an internal medicine or endocrinology specialist, an anaesthetist, a dietitian and, where needed, a psychologist or psychiatrist.

Blood tests: blood sugar, thyroid, liver and kidney function, vitamin and mineral levels
Upper gastrointestinal endoscopy to examine the stomach and oesophagus
Abdominal ultrasound, chest X-ray, lung and heart assessment
A sleep study if sleep apnoea is suspected
Assessment of eating habits and eating behaviour

Smoking impairs wound healing and raises the risk of a leak, so it must be stopped before surgery. Some patients are advised to follow a low-calorie, mainly liquid diet for 1–2 weeks before the operation to shrink the liver.

How Is Gastric Sleeve Surgery Performed?

The operation is performed under general anaesthesia using the laparoscopic (keyhole) technique. A camera and fine instruments are introduced through 4–5 small openings in the abdominal wall.

The blood vessels supplying the outer curve of the stomach are divided
Guided by a calibrated tube (bougie) placed in the stomach, the stomach is cut and sealed along its length with a stapler
The staple line is checked for bleeding and leaks
The removed part of the stomach is taken out through one of the small openings

The operation usually takes 1–2 hours. The hospital stay is generally 2–3 days. Bariatric operations should be performed in fully equipped hospitals that can provide intensive care support if needed.

Recovery After a Gastric Sleeve

The first days

You start walking a few hours after surgery; moving early lowers the risk of blood clots. Anti-clotting injections and compression stockings are used. After a check, water and clear liquids are started in small sips.

The first weeks

Your diet moves step by step from liquids to purées and then to soft foods. Returning to desk work is usually possible within 1–2 weeks. Heavy lifting and strenuous exercise are generally postponed for 4–6 weeks.

The first year

Weight loss is fastest in the first 6–12 months. During this period, dietitian and doctor check-ups, monitoring of blood values and regular exercise are decisive for lasting results.

Possible Risks and Side Effects

A gastric sleeve is considered a safe operation when performed by experienced teams, but like any surgery it carries risks:

A leak from the staple line (the most serious complication of the early post-operative period)
Bleeding and infection
Blood clots and pulmonary embolism
New or worsening reflux
Narrowing of the stomach
Vitamin and mineral deficiencies (especially B12, iron and vitamin D)
Gallstones and temporary hair loss linked to rapid weight loss

Risks vary with age, weight and related conditions and are discussed in detail at your consultation.

Results and Long-Term Follow-Up

Studies report that, on average, more than half of excess weight is lost in the first 1–2 years after a gastric sleeve. Conditions such as type 2 diabetes, high blood pressure and sleep apnoea often improve markedly. However, results vary from person to person and cannot be guaranteed.

The stomach may stretch somewhat over time, and weight can be regained over the years if the eating plan is not followed. Lifelong vitamin supplements, a blood test at least once a year and nutritional follow-up are therefore recommended. Body contouring can be planned later for skin left loose after weight loss.

Factors That Affect the Cost of Gastric Sleeve Surgery

The cost depends on the scope of pre-operative tests, the length of the hospital stay, the number of staplers used, any preparation required by other conditions and the post-operative follow-up package. A precise figure is given individually after your consultation and tests.

Treatment Process

Assessment and Tests

Your weight history, related conditions and test results are reviewed by the team, and together you decide whether a gastric sleeve is the right method for you.

Laparoscopic Surgery

About 75–80 percent of the stomach is removed through small openings, and the staple line is checked during the operation.

Nutrition and Follow-Up

A step-by-step diet from liquids to normal food is followed, and weight loss, vitamin levels and overall health are monitored at regular check-ups.

Who is it suitable for?

Adults with a BMI of 40 or above
People with a BMI of 35 or above and an obesity-related condition
People unable to lose weight permanently with diet and exercise
People ready to follow the post-operative nutrition and check-up plan

Quick Facts

Duration: 1–2 hours
Treatment Model: Single operation + long-term nutritional follow-up
Recovery: 2–3 days in hospital, return to work usually within 1–2 weeks
Method: Laparoscopic sleeve gastrectomy under general anaesthesia

Frequently Asked Questions

How much weight can I lose with a gastric sleeve?

Studies report that, on average, more than half of excess weight is lost in the first 1–2 years. The result depends on your starting weight, eating habits and exercise and cannot be guaranteed.

Can a gastric sleeve be reversed?

No. The removed part of the stomach cannot be put back. If needed, a gastric sleeve can be converted to another operation, such as a gastric bypass.

Does a gastric sleeve cause reflux?

In some patients reflux can start or get worse. For people who already have severe reflux before surgery, a gastric bypass may be a better option; this is assessed with an endoscopy.

When can I return to work after surgery?

Desk work can usually be resumed within 1–2 weeks. Physically demanding jobs and strenuous exercise are generally postponed for 4–6 weeks.

Will I need to take vitamins for life?

Yes, most patients are advised to take a multivitamin for life; B12, iron, calcium and vitamin D needs are checked regularly with blood tests.