Laparoscopic Sleeve Gastrectomy
What is a gastric sleeve?
The gastric sleeve is a common and effective weight loss surgical option. It involves laparoscopic (key hole) surgery to remove 2/3rds of the stomach, reducing the stomach from a large bag like shape holding approximately 2000mL to a thin tubular sleeve that can hold approximately 150mL.
How does it work as a tool for weight loss?
The gastric sleeve works in three core ways to assist with weight loss.
- Stomach size reduction
- More than 2/3rds of the (lateral) side of the stomach is removed. This means the stomach is reduced from a large curved bag to a small tubular structure. With a smaller stomach, you can physically fit a much smaller amount of food and fluids into the stomach at any given time. Less food leads to reduce caloric intake and thus weight loss.
- Reduced hunger hormone ‘Grehlin’
- Parietal cells are located in the lining of the stomach. Parietal cells produce the hunger hormone ‘grehlin’. Reducing the size of the stomach reduces the amount of grehlin produced.
- Reduces appetite and improves metabolism: Grehlin acts on the brain to stimulate appetite, as well as acting of fat cells to store fat and increases growth hormone which also stimulates appetite and fat storage. With a large portion of the stomach removed, the amount of hunger hormone grehlin is also greatly reduced, thus reducing hunger. Less hunger leads to reduce caloric intake and thus weight loss.
- Improves insulin resistance: Grehlin suppresses insulin production from the pancreas, reduced grehlin and an increase in 2 other metabolic hormones (GLP-1 and PYY) that increase following a gastric sleeve, leads to increased insulin secretion and improvement in insulin sensitivity and improved diabetic control with weight loss.
- Neurohormonal pathway alternations reduce appetite, improve metabolism and reduce insulin resistance.
Studies show that both the gastric sleeve and gastric bypass affect key neurohormonal pathways leading to appetite suppression and an increase in metabolism. This also assists with resetting the ‘weight set point’ and use of calories consumed.
Advantages of a gastric sleeve
Current literature shows an average of 60% excess weight loss within the first 1-2 years. Results vary for individuals and many patients achieve more weight loss.
- Weight loss leads to a significant improvement in obesity related health conditions and can improve quality of life. Some people will reduce or cease medications for co-morbidities ie. type II diabetes, high blood pressure, cholesterol, cancer risk, cardiovascular disease, fatty liver, sleep apnoea, joint pain.
- Long term a normal diet can be consumed, just in smaller volumes.
- Unlikely to have dumping syndrome
- Minimal malabsorption of vitamins and minerals
- Can be used as a safer option to bypass surgery as a first stage operation for super obese patients.
Disadvantages of a gastric sleeve
- Gastro-oesophageal reflux
- Excess skin with weight loss
- Stomach sleeve dilation long term and weight regain possible
- Complications are uncommon and several measures are taken to reduce risk of complications
- General surgical complications
- Sleeve specific complications/issues: Staple line bleed or leak <1%, Stricture of the stomach