Bariatric Surgery

Overview

Bariatric surgery changes the size of the stomach and, in some operations, the route food takes through the gut. You feel full after a small amount of food, and the operation also changes the gut hormones that drive hunger and control blood sugar. That second effect is why doctors also call it metabolic surgery, and why it can improve type 2 diabetes within weeks, sometimes before much weight has been lost.

Almost all bariatric operations today are laparoscopic (keyhole), done through four to six small cuts with a camera and long, thin instruments. The two operations you will hear about most are:

• Sleeve gastrectomy. The surgeon removes about three quarters of the stomach along its length, leaving a narrow tube, or sleeve, roughly the shape of a banana. It cannot be reversed.
• Roux-en-Y gastric bypass. The surgeon makes a small stomach pouch about the size of an egg and connects it to a lower part of the small intestine. Food then bypasses most of the stomach and the first part of the intestine.

A one anastomosis (or "mini") gastric bypass is a variation with a single join. Adjustable gastric bands are used far less often than they once were.

Hospitals in many countries do these operations regularly. Patients from the United States and Canada often look at Mexico, and many from Europe and the Middle East look at Turkey, while others compare India, Thailand or Malaysia. You can ask for quotes from more than one country.

Who needs it

Doctors use BMI (body mass index, your weight in kilograms divided by your height in metres squared) as a starting point. International guidelines published in 2022 by two surgical societies suggest:

• BMI of 35 or more: surgery is recommended, with or without weight-related illness.
• BMI of 30 to 34.9 with metabolic disease such as type 2 diabetes: surgery should be considered, particularly when other treatment has not worked.
• People of Asian descent develop weight-related illness at lower BMI, so lower thresholds apply, with surgery offered from a BMI of about 27.5.

Conditions that often improve after surgery include type 2 diabetes, high blood pressure, sleep apnoea (breathing that stops and starts during sleep), fatty liver disease and joint pain in the knees and back.

BMI is only part of the decision. The surgeon also wants to know that you understand this is a lifelong change in how you eat, that you are ready to stop smoking (smoking raises the risk of ulcers and leaks), and that problems such as binge eating or heavy drinking are being treated. A surgeon may advise against surgery, or advise waiting, if your heart or lung risk is too high or a pregnancy is planned soon.

The choice between a sleeve and a bypass depends on you. Acid reflux often tips the advice towards a bypass, because a sleeve can make reflux worse. A sleeve is a shorter operation and leaves the intestine as it is.

How it is done

Before surgery

Tests before the operation usually include:

• Blood tests: blood count, kidney and liver function, HbA1c, thyroid, and vitamin and iron levels.
• An ECG (a tracing of the heart's electrical activity) and a chest X-ray, with an echocardiogram (an ultrasound scan of the heart) if needed.
• An upper GI endoscopy, where a thin camera looks into the oesophagus and stomach for ulcers, a hiatus hernia or H. pylori infection.
• An abdominal ultrasound to look for gallstones.
• A sleep study if sleep apnoea is suspected.
• A talk with a dietitian, and with a psychologist at many hospitals.

Many surgeons ask you to follow a low-calorie liquid or low-carbohydrate diet for one to two weeks before surgery. It shrinks the liver, which sits over the stomach, and makes the operation safer. You start this at home, before you fly.

The operation

You are under general anaesthesia. A sleeve usually takes about an hour and a bypass a little longer. The surgeon divides the stomach with a stapling device that cuts and seals at the same time, and many surgeons test the staple line for leaks before finishing.

You wake with small dressings, medicine for pain and nausea, and compression stockings or pumps on your legs. Nurses will want you walking the same evening, and blood-thinning injections are usually given to lower the risk of clots.

Recovery and how long you stay

You spend 2 to 3 days in hospital. You start with sips of water, then clear fluids. Some hospitals do a swallow X-ray with contrast dye to check the stomach before discharge. You leave once you can drink enough, walk comfortably and control pain with tablets or liquid medicine.

Your diet then moves through stages over about six to eight weeks. Your hospital's dietitian gives the exact plan, but a typical pattern is:

1. Clear liquids for the first day or two.
2. Full liquids and protein shakes for about two weeks.
3. Pureed food for about two weeks.
4. Soft food for a further two weeks or so.
5. Normal textures in small portions after that.

Dietitians usually advise sipping slowly through the day, eating protein first, keeping drinks separate from meals, and avoiding fizzy and sugary drinks. After a bypass, sugary food can cause dumping syndrome (sweating, a racing heart and diarrhoea soon after eating).

Plan on 1 to 2 weeks at your destination. That covers tests before surgery, the hospital stay and a check about a week after the operation. For the flight home, surgeons usually advise compression stockings, an aisle seat, walking every hour and steady sips of water, and some prescribe blood-thinning injections for the days around the flight.

Follow up lasts for life. That means daily vitamins, blood tests at regular intervals, and contact with a dietitian. MediCurage books a room near the hospital with a fridge for your liquids and shakes, and once you are home your coordinator makes sure your blood test results reach the surgical team.

Questions to ask your surgeon

1. Would you advise a sleeve or a bypass for me, and why?
2. I have acid reflux. How does that change your advice?
3. Do I need a diet before surgery, and when should I start it?
4. Which vitamins and supplements will I take, in what doses, and which blood tests should I repeat at home?
5. When can I fly, and will I need blood-thinning injections for the flight?
6. Which symptoms after I get home, such as fever, a fast heartbeat or worsening pain, mean I should call you?
7. How should my diabetes or blood pressure medicines change after surgery?
8. Can I keep in touch with your dietitian by video call once I am home?
9. If something goes wrong after I return home, who will look after me, and how do you work with my local doctor?

Before you travel, ask your family doctor whether they will look after your blood tests and prescriptions in the years ahead, and bring them a copy of the surgeon's discharge letter when you get back.