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Gastric Bypass Surgery

What Is Gastric Bypass Surgery?

Gastric bypass has been described as the ‘gold standard’ weight control operation and has been the most frequently performed weight loss surgery procedure worldwide.

Gastric bypass has been described as the ‘gold standard’ weight control operation and has been the most frequently performed weight loss surgery procedure worldwide. It is the operation to which all other bariatric procedures are compared, and it has the best – and best known – long-term results.
The operation is truly a bypass of the stomach. Most of the stomach is bypassed (unlike the gastric sleeve, where most of the stomach is removed) so that food eaten goes into a small gastric pouch (15-30mL) and then into a loop of the small bowel (the jejunum) for digestion. Gastric bypass surgery, unlike a sleeve gastrectomy, is reversible. The stomach and bowel can be reconnected, although this requires another operation.

There are several different types of gastric bypass surgery available: the Roux-en-Y Gastric Bypass (banded or unbranded), the Mini Gastric Bypass and the One-anastomosis Gastric Bypass (banded or unbanded).

Having a gastric bypass means taking on the responsibility of looking after your health long-term.

Am I a Candidate for a Gastric Bypass?

As with all weight loss surgeries, gastric sleeve surgery should only be performed on people with a BMI greater than 40, or those with a BMI over 35 with other medical co-morbidities such as diabetes or high blood pressure.

Occasionally patients with BMI under 35 may also undertake this operation; however, the balance between risk and benefit is harder to gauge. Patients who are lighter than this run the risk of losing weight but at the expense of complications that can make them worse off. Other weight loss therapies should have been tried beforehand but have been unsuccessful.

Patients with eating disorders such as binge eating or a nocturnal eating disorder, and patients who habitually graze or emotionally eat, need to seek treatments for these disorders as well, otherwise, the surgery will fail after being initially successful.
Patient Journey

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How Gastric Bypass Surgery Causes Weight Loss

The gastric bypass surgery itself does not make you lose weight. Overeating is limited by the new small and tight stomach.
Too much food causes discomfort and vomiting. If possible, your surgeon may put a silicone ring around the stomach, which helps prevent the stomach from stretching in the future (the banded bypass).

Satiety (being satisfied early in a meal) is induced by the small stomach and through the ‘switching off’ of the hormones that cause hunger. Many patients go for months before they have any recognisable hunger sensations, and they often have to remind themselves to eat.

The operation often causes intolerance to sweets and high-density carbohydrates as well as fatty, oily food. These foods run quickly into the small bowel and cause unpleasant symptoms called ‘dumping’. There is trivial malabsorption of fat, as the food eaten is initially not mixed with bile and pancreatic juice (there is no protein or carbohydrate malabsorption).

Advantages of Gastric Bypass Surgery

  • Generally, the gastric bypass requires a short hospital stay of 2–3 days, and patients find it OK to return to work by about two weeks.
  • The advantages of gastric bypass surgery are clear; it has been proven to significantly reduce a patient’s weight not only immediately following the surgery, but for up to 20 years afterwards.
  • Patients can lose up to 30 – 50% of total body weight as a result of gastric bypass surgery. Patients have demonstrated that with this form of surgery it is easier to maintain long-term results.
  • With such significant weight loss, patients will then see other health benefits as a result such as Type 2 Diabetes going into sustained remission, ease of joint pain such as knees, ease of breathing and other health benefits

Drawbacks of Gastric Bypass Surgery

  • As with every surgery, this operation poses risks to the patient. However, the operation is invariably performed laparoscopically which means less chance of infection and much quicker recovery times. But of course, this can vary from case to case. Most patients recommended for this surgery will fail to lose a significant amount of weight without it and can face even more serious risks to their health long term.
  • Gastric bypass surgery affects how your body absorbs the food you eat, so there is a risk of various deficiencies occurring. All patients having bypass surgery need a minimum of a daily multivitamin and at least 6 monthly vitamin B12 injections. Other items including Vitamin D, calcium and iron will be needed by many patients.
  • Gastric bypass surgery can also result in a condition that is referred to as “dumping syndrome”; this is when food, in particular sugar, moves through the digestive system too quickly and can cause nausea, diarrhoea and reflux. This is why patients are advised not to eat foods with a high sugar content following surgery.

Do you know this procedure can be performed using a surgical robot ?

This advanced technology allows surgeons to operate with enhanced precision and visualisation.
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FAQs

We provide tailored, patient-centred care that includes varying bariatric surgery options and follow-up care by the team to ensure that you achieve your weight loss goals. Because each patient is different, therefore each treatment plan is different, it is very difficult to provide a one size fits all cost example. For a comprehensive cost breakdown, please visit our Bariatric Surgery Costs page.

By making an appointment with one of the specialists here at UGIS, they can discuss your individual needs and provide an accurate quote of surgery costs (for both insured and uninsured patients).

A gastric bypass is considered a permanent procedure, but in rare cases, it can be reversed. Reversal is technically possible because the stomach and intestines are restructured rather than removed. However, it is a complex operation and is usually only considered if there are serious medical complications that cannot be managed in other ways. Most patients do not require reversal, and the procedure is intended to be a long-term solution for weight loss and health improvement.

Dumping syndrome is relatively common after a gastric bypass, affecting up to 50% of patients to some degree. It occurs when food moves too quickly from the stomach into the small intestine, especially after eating foods high in sugar or fat. Symptoms can include nausea, diarrhoea, abdominal cramps, dizziness, and a rapid heart rate. While it can be uncomfortable, dumping syndrome often improves over time and can usually be managed with dietary changes, such as eating smaller meals, avoiding high-sugar foods, and drinking fluids between meals rather than with them.

A mini gastric bypass, or One Anastomosis Gastric Bypass (OAGB), is a simpler alternative to the traditional Roux-en-Y gastric bypass. It involves creating a long, narrow stomach pouch and connecting it to a loop of small intestine, using just one join instead of two. This often means a shorter operation time and potentially lower risk of complications. However, MGB may not be suitable for patients with reflux or certain anatomical considerations. To learn more about how it compares to a standard gastric bypass, read our full blog here: .

A gastric bypass changes your digestion and limits the amount of food consumed at a mealtime therefore limiting the nutrients your body can absorb. Studies undertaken on patients who have had Bariatric surgery indicate that as many as 15% will end up with neurological (nervous system) disorders if they don’t take supplementary vitamins. As a result, it is important to take multivitamins daily for the rest of your life to protect you from long-term deficiencies.

Why Choose Upper GI Surgery?

12 Months of Follow-up Appointments
Our patients benefit from having access to follow-up appointments with a Bariatric Specialist for the year after surgery, which is included in the clinic fee.
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Over 25 Years of Experience
Our Bariatric surgery expertise is second to none. We have Australian-leading experience in many procedures, including the less commonly performed complex revision and robotic surgery.
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Our Dedicated Support Team
Our welcoming and committed team is comprised of Nurses, Dietitian and Psychologist, as well as Admin support staff, making sure you are in the best hands for the duration of your treatment and the crucial aftercare period.
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Ongoing Care Program (OCP)
Our Ongoing Care Program provides continuous support, offering access to helpful resources and expert guidance to ensure you stay on track and achieve lasting success in your weight loss journey.
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Bariatric Centre of Excellence
Surgical Review Corporation (SRC) accreditation is achieved by providing the highest quality of care to patients as determined by an independent, external process of evaluation.
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Bariatric Surgery Registry (BSR) Leading Contributors
We have contributed data since the BSR was first available in NSW and are pleased to report that our audit results are excellent. Audit is part of the “quality mindset” driving us towards excellence.
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Ready to take the next step?

If obesity is affecting your quality of life, book a consultation to discuss targeted testing and a treatment plan tailored to your symptoms and goals.

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Suite 3 Level 5 1 South St,
Kogarah NSW 2217

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F: 02 9553 7526
E: info@uppergisurgery.com.au

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