What is gastric bypass surgery?

Gastric bypass surgery is similar to gastric banding in the way it divides the stomach to create a small pouch at the top. However, instead of the food passing normally on to the rest of the stomach for digestion, a section of small intestine is grafted on to the end of the first stomach section, bypassing the rest of the stomach.

The risks of the surgery

As with all operations that involve general anaesthetic, gastric bypass surgery carries risks. However, in this case, the complexity of the procedure means that these risks are significantly higher, with some studies showing a fatality rate as high as one in fifty patients within thirty days of the surgery.

The fact that patients undergoing weight-loss surgery are usually morbidly obese increases the problems associated with gastric bypass surgery. Being so overweight often mean you have heart problems, breathing difficulties, and general poor health and fitness, which clearly complicate the procedure and raise the risk level.

This article on gastric bypass surgery is written by Jackie Griffiths, a freelance journalist who writes health, medical, biological, and pharmaceutical articles for national and international journals, newsletters and web sites.

Although gastric bypass can be done laparoscopically (keyhole surgery), the size of the patient and amount of body fat around the surgery site often means this is not possible. The alternative ‘open’ surgery naturally carries higher risks, and the larger wound site is far more prone to infection.

There are a range of complications which can occur during the surgery itself, including:

  • Perforation of the stomach or oesophagus
  • Damage to major blood vessels
  • Spleen or liver damage
  • Blood clots
  • Adhesions

Post-operative complications

The most common post-op complication with gastric bypass surgery is leakage, from either the stomach staples or the intestinal graft site. This can cause peritonitis and can be life-threatening. Leakage occurs in around one in twenty operations.

Changes in the make-up of the stomach leads to ulcers in around 4% of cases, while the poor muscle tone and general health of obese patients means there is a 2.5% risk that the wound will herniate.

Nutritional deficiencies after the surgery

By far, the largest risk with gastric bypass surgery is nutritional deficiency following the procedure. Since you are bypassing the normal digestive route, you will not absorb fats and other nutrients in the same way that you used to. This can lead to a wide range of deficiencies, including major vitamins and minerals that are vital for good health.

You may also find that you’re no longer absorbing sufficient calories, leaving you feeling lethargic and low on energy. However, your consultant will help you establish a new dietary routine to suit your new digestive system, and recommend supplements to maintain your vitamin and mineral levels.

If you do not change your diet, you risk what is called ‘Dumping Syndrome’, which can lead to abdominal and chest cramps, nausea, sweating and diarrhoea. However, this can be controlled by eliminating sugary foods from your diet.

Problems with rapid weight loss

The rapid weight loss associated with Gastric Bypass Surgery can lead to gallstones in around one in fifty patients. Most patients will also have problems with excess skin. Both of these conditions will require further surgery and this should be considered when making your initial decision.

So, is it safe?

Gastric bypass surgery is a major operation and cannot easily be reversed like other forms of weight loss surgery, so it should only be considered as an absolute last resort. You will have to be very careful with your diet and eating habits for the rest of your life following the procedure.

However, there are many studies that show that the surgery significantly increases life expectancy for the morbidly obese. One Canadian study found an 89% reduction in the risk of death in the five years following surgery, compared to morbidly obese people who had not had the procedure. Gastric bypass surgery may be a complex and risky operation, but if it is your only alternative then the risk of not having it may be far greater.

As with any surgery you should discuss your treatment in depth, and weigh up the risks and rewards carefully with your consultant or surgeon before you go ahead with gastric bypass surgery.

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