Gastric Bypass Surgery

Gastric bypass, or Roux-en-Y gastric bypass (RYGB), is one of the most common and effective bariatric surgeries for weight loss. It not only reduces the stomach’s size but also reroutes the small intestines, which alters the absorption of nutrients.

The primary goal of gastric bypass surgery is to help people with obesity lose weight, which can then reduce the risk of other health problems like heart disease, high blood pressure, type-2 diabetes, and certain cancers.

The decision to undertake gastric sleeve surgery is usually thought about only after other options have been tried, such as dieting, exercise and other therapies.

Patient Selection:

Patients with a BMI score of 30 of over may be candidates for surgery. A wide range of lifestyle and psychological factors are reviewed prior to surgery, including prior attempts at dieting and losing weight, whether you have an underlying obesity-related medical condition that is increasing your risks of mortality, and whether you have sought psychological care and assessment in relation to your obesity.

Mechanism of Action:

Gastric bypass surgery involves permanently altering the stomach.  The surgery is performed laparoscopically (“keyhole” surgery), meaning it is minimally invasive with a few small incisions in the abdomen.

During gastric bypass surgery:

  • Stomach Size Reduction: The surgeon creates a small pouch (about the size of an egg) from the upper-part of the stomach – completely separating it from the rest of the stomach, which limits the amount of food that can be consumed at one time.
  • Bypassing the Duodenum: The small intestine is divided, and the lower portion is attached to the stomach pouch, bypassing the duodenum and part of the small intestine. This reduces the absorption of calories and nutrients from food.
  • Hormonal Changes: The procedure alters gut hormone signals that control appetite and metabolism, leading to reduced hunger and increased feelings of fullness.
  • Hormonal Changes: The surgery creates positive changes in gut hormones, which can reduce appetite, increase satiety, and enhance insulin sensitivity.
  • Significant Weight Loss: Gastric bypass surgery typically results in substantial weight loss, often achieving 60-80% of excess weight loss within the first year.
  • Resolution of Obesity-Related Conditions: Many individuals experience improvements or remission of obesity-related conditions such as type-2 diabetes, hypertension, and sleep apnoea.
  • Long-Term Effectiveness: The surgery can lead to long-term weight loss maintenance when accompanied by dietary and lifestyle changes.
  • Enhanced Quality of Life: Weight loss and improved health can lead to increased energy, improved mobility and a reduction in joint pain, and a better overall quality of life.
  • Lowered Risk of Obesity-Related Mortality: Reduced obesity-related health risks can extend life expectancy.

Due to the reduced stomach size, patients may need to make dietary adjustments to ensure they are getting all the necessary nutrients. It is crucial to work closely with a nutritionist or dietitian after surgery.

It is important to note that gastric bypass surgery is not without risks and complications. Potential complications include:

  • Dumping syndrome: When food moves too quickly into the small intestine, it can cause nausea, vomiting, diarrhea, and dizziness
  • Leaks at the surgical connections
  • Nutritional deficiencies: Due to reduced nutrient absorption, which might necessitate lifelong supplements
  • Strictures or blockages
  • Risk of ulcers
  • Potential for weight regain over time

The decision to undergo this surgery should be made in consultation with a healthcare provider and a thorough evaluation of the risks and benefits. Additionally, post-surgery, individuals must commit to significant dietary and lifestyle changes to maximise the benefits and maintain weight loss.

Dr Devesh Kaushal is a Specialist General Surgeon and a Fellow of the Royal Australian College of Surgeons (FRACS).

Dr Kaushal offers 15+ years of experience and holds a Master of Surgery Degree, as well as being fully certified in gastroscopy and colonoscopy by the Gastroenterology Society of Australia (GESA).

Dr Kaushal takes an empathetic, warm-hearted and friendly approach to patient care and is completely dedicated to patient outcomes.

He consults and operates across Souther-Western Sydney.