11 Things You Need to Know About a Gastric Bypass Surgery

Estimated Reading Time: 10 minutes

More than half of the UK population is overweight

More people are now seeking weight loss treatment and bariatric surgery. The UK has the third highest rates in Western Europe, with 67% of men and 57% of women being either overweight or obese, according to the Global Burden of Disease study, published in the Lancet medical journal¹.

Gold standard of weight loss surgery

The Roux-en-Y gastric bypass is considered the ‘gold standard’ of weight loss surgery and is the most commonly performed bariatric procedure worldwide².

1. What is gastric bypass surgery?

Gastric bypass surgery helps you lose weight by changing how your stomach and small intestine handle the food you eat.

After the surgery, your stomach will be smaller. You will feel full with less food.

The food you eat will no longer go into some parts of your stomach and small intestine that breaks down food.³.

A gastric bypass is known as a restrictive operation as it restricts both food intake and the amount of calories and nutrients the body absorbs. It is generally considered irreversible and permanently changes how your body digests food.

Mr James Ramus MD, FRCS - Consultant General, Upper GI and Bariatric Surgeon at Berkshire Independent Hospital in Reading comments on a common misunderstanding in modern Bariatric procedures. 'The gastric bypass is not meant to be a 'malabsorptive' procedure. i.e. you do not malabsorb calories. The bypass works partly as a restrictive procedure but perhaps the main benefits in the procedure are the changes in gut hormones that occur afterwards'

2. What is involved in a gastric bypass?

“The gastric bypass acts by decreasing the stomach capacity but also by allowing the passage of food into the jejunum (part of the small bowel we join to the new stomach pouch) - this induces a number of gut hormone changes that leads to increased satiety (makes you feel full) and generally stops you feeling hungry all of the time” says Mr Ramus. “It is also these hormonal changes that lead to a vast improvement in your 'insulin' resistance and therefore improve your blood sugar control (reverse your diabetes).”

There are two steps during gastric bypass surgery:

Step 1 - Make your stomach smaller
Your surgeon will make your stomach smaller using staples. Your food intake will then be limited by a smaller stomach.

Step 2 - The bypass
Your surgeon will connect your smaller stomach to a section of your small intestine, bypassing the rest of your stomach and some of your small intestine.

3. Roux-en-Y bypass (RNY) Procedure

The Roux-en-Y gastric bypass procedure involves creating a stomach pouch using staples out of a small portion of the top part of the stomach. This restricts the amount of food you can eat. The bottom part of the stomach that is no longer used is called the "blind" stomach. The pylorus is at the bottom of the "blind" stomach and is no longer used to control food moving into the intestine.

The top stomach pouch is attached directly to the small intestine, bypassing a large part of the stomach and the first portion of the small intestine called the duodenum. Food passes through the anastomosis (connection) created between the pouch and the small intestine, which is deliberately made quite narrow to keep food in the pouch longer, making you feel fuller longer.

4. Laparoscopic or open surgery

Gastric bypass can be done in two ways under general anaesthesia:

a) Laparoscopic surgery

A tiny camera, called a laparoscope, is placed in your stomach. First, your surgeon will make 4 to 6 small cuts in your stomach. Then your surgeon will pass the laparoscope through one of these cuts. It will be connected to a video monitor in the operating room. Your surgeon will look at the monitor to see inside your stomach. Your surgeon will use thin surgical instruments to do your bypass. These instruments will be inserted through the other cuts.

b) Open surgery

Your surgeon will make a large surgical cut to open up your stomach. Your surgeon will do the bypass by working on your stomach, small intestine, and other organs.

Most bariatric procedures today are performed using minimally invasive techniques (laparoscopic surgery) with a small chance to convert to open surgery if needed. Advantages of laparoscopy over open surgery include a shorter procedure and hospital stay, quicker recovery, less pain, smaller scars and a much lower risk of getting a hernia or infection.

5. Am I eligible for a gastric bypass?

You will usually have weight-loss surgery if you cannot lose a large amount of weight and keep it off by dieting, changing your behaviour and exercising alone; or if you have serious health problems caused by obesity.

Doctors often use the body mass index (BMI) and health conditions such as diabetes, high blood pressure, sleep apnoea, joint pain and depression to determine which patients are most likely to benefit from weight-loss surgery.

Your bariatric surgeon will discuss the best option of weight loss with you and if you are eligible for gastric bypass surgery.

6. The benefits of the gastric bypass surgery

Gastric bypass surgery is a highly effective weight loss procedure. Weight loss tends to be more rapid and dramatic than other weight loss procedures. So if you are looking for a weight loss surgery that will offer you the best chance of losing the most weight then gastric bypass surgery might be the option for you.

In general, gastric bypass patients will lose around 70 percent of their excess weight, sleeve gastrectomy patients will lose around 60 percent, and gastric banding patients will lose around 50 percent.⁵ However, the amount of weight lost by each patient will vary depending on individual circumstances.

After a gastric bypass you'll probably feel dramatically better with rapid improvements in conditions affected by obesity such as diabetes and hypertension, high blood pressure, high cholesterol, asthma, arthritis, sleep apnoea and heartburn. Weighing less should also make it much easier for you to move around and do your everyday activities, improving your quality of life.

Gastric bypass offers good long-term results and many people are able to keep most of the weight off.

7. What are the risks?

Gastric bypass is major surgery and so carries risks, some being very serious. You should discuss these with your surgeon.

The greatest risk with this type of surgery surrounds the possibility of developing blood clots in your legs (deep vein thrombosis or ‘DVT’) and you’re most at risk of this in the first 6 weeks after the operation. However, compression stockings and the occasional use of a compression pump along with blood thinning drugs are used to try to prevent this from happening⁶.

8. Complications that may occur

• Leakage at the many sites of reconnecting the stomach and intestine.
• Shrinkage (stricture) of openings into the intestine.
• Dumping of your food into the intestines too quickly before it’s been properly digested is common and can cause nausea and vomiting, bloating, dizziness, sweating and diarrhoea. Dumping can also be viewed as a benefit as it helps patients avoid eating weight gaining sugary and high fat foods that lead to dumping.
• Gallstones may develop after rapid weight loss
• You'll have to be careful with your diet, take long term vitamins and minerals to prevent development of vitamin/mineral deficiency and you may need some nutrients in your blood to be monitored.
• Distension of the blind stomach. This is rare, but needs to be diagnosed and treated urgently.

9. Getting prepared for your gastric bypass

• If you are a smoker, you should stop smoking several weeks before surgery and not start smoking again after surgery. Smoking slows recovery and increases the risks of problems.
• You may be asked to stop taking drugs such as aspirin, ibuprofen (Advil, Motrin), vitamin E, warfarin (Coumadin), and any other drugs that make it hard for your blood to clot. You should ask your doctor about the drugs you can still take on the day of your surgery.
• Prepare your home for after the surgery.

10. After gastric bypass surgery

Most patients can be sent home within 3 to 5 days after surgery. You will be able to go home when you are able to move around without a lot of pain and you can eat liquid or pureed food without vomiting.

11. Weight loss needs your commitment too

Gastric bypass surgery isn't a magic wand for obesity. To lose weight and avoid complications from the procedure you will need to follow exercise and eating guidelines given by your surgeon. These will include limiting quantities of food to about a cupful per meal and how to prevent nutritional deficiencies.

Careful follow-up and constant motivation are helpful to prevent problems occurring. Lifestyle changes after surgery can be the hardest part of the recovery process. Patients who have the greatest success with any bariatric surgery adopt moderate eating and exercise habits to maintain their weight loss over a long period of time.

Here you can find our guide prices for gastric bypass surgery

Read more weight loss surgery blog posts to find answers to the most common questions including: pros and cons of gastric balloon and gastric sleeve, how to choose a weight loss surgeon, exercise after weight loss surgery etc.

Thank you

Big “thank you” to Mr James Ramus MD, FRCS - Consultant General, Upper GI and Bariatric Surgeon at Berkshire Independent Hospital in Reading for reviewing this article.

Mr James Ramus is a Fellow of the Royal college of Surgeons of England, Association of Upper GI Surgeons, British Obesity and Metabolic Surgery Society, International Federation of Surgeons for Obesity and Metabolic Disorders.

Read more about Mr Ramus’s qualifications, background and clinical interests.

About Ramsay Health Care gastric bypass surgery

Ramsay Health Care is a leading provider of weight loss surgery in the UK. Our highly qualified and experienced bariatric surgeons will discuss with you the best weight loss options for your individual needs.

Please contact us if you would like to discuss gastric bypass surgery in more detail.


¹ http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)60460-8/fulltext#article_upsell
² http://asmbs.org/obesity-and-surgery-learning-center/bariatric-surgery-procedures/
³ http://www.nlm.nih.gov/medlineplus/ency/article/007199.htm
⁴ http://www.dsfacts.com
⁵ http://www.obesityaction.org/educational-resources/resource-articles-2/weight-loss-surgery/choosing-the-right-weight-loss-surgery-procedure
⁶ http://www.aboutoperations.co.uk/gastric-bypass-surgery-explained.html

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