CHI Memorial Medical Group

Gastric Sleeve


The sleeve gastrectomy, also referred to as gastric sleeve surgery, is a very effective operation that can be done laparoscopic with small incisions and allows patients to lose weight and reduce hunger.

The weight loss with the sleeve gastrectomy has been in the range of 50% to 60% of the excess body weight. This operation is the only bariatric procedure that has no malabsorption (as the gastric bypass Roux-en-Y and Duodenal Switch do) and no foreign body (as the gastric banding does). It has a lower risk compared to the Gastric Bypass, and the relative invasiveness of the procedure is in between the bypass and the banding procedure.


A primary reason people lose weight with the gastric sleeve is because of the significantly smaller stomach size. The reduction of the size of the stomach, to about 60 – 80 cc in volume results in a powerful restrictive weight loss. This is about 7–80% smaller than the normal stomach size. As a result, patients feel full after a very small amount of food, and therefore lose weight because they eat less, and they are happy eating less.

Decreased Hunger

There are also significant effects on the hunger mechanisms that make the weight loss seen with the sleeve gastrectomy even better than would be seen just with a small stomach pouch. Hunger is favorably affected because there is a reduced capacity to produce ghrelin, a substance that plays a role in how you feel, and relieves hunger.

Preservation of Pyloric Valve

Another important fact about the sleeve is that it preserves the pylorus, which is the valve that regulates emptying of the stomach. This acts as a “natural band” and allows food to hold up in the stomach for a while, making the person feel full while the food trickles out. Coupled with the fact that there is no rearrangement of the bowel, it also means dumping and marginal ulcers are not a problem. The normal satiety mechanism (feeling of fullness) is enhanced by this mechanism.

The Operation

The sleeve gastrectomy (gastric sleeve surgery) operation is done with 5 small incisions, and takes about an hour to do. The stomach is restricted by dividing it vertically and removing more than 85% of it. This part of the procedure is not reversible.

The stomach that remains is shaped like a banana and measures from 1-2 ounces (40-80cc). The nerves to the stomach and the outlet valve (pylorus) remain intact with the idea of preserving the functions of the stomach while reducing the volume.

By comparison, in a Roux-en-Y gastric bypass, the stomach is divided, not removed, and the pylorus is excluded. Note that there is no intestinal bypass with this procedure, only stomach reduction.

Having the laparoscopic sleeve gastrectomy involves an overnight stay in the hospital. There is no nasogastric tube, and you are able to return to work, resume heavy lifting and strenuous activity, in most cases, in about two weeks from the time of surgery. If you are able to do light duty at work, there is the possibility of going back to work sooner than two weeks for some patients.

What are the advantages?

  • The stomach is reduced in volume but tends to function normally so most food items can be consumed, albeit in small amounts
  • Eliminates the portion of the stomach that produces the hormones that stimulate hunger (ghrelin)
  • No dumping syndrome because the pylorus is preserved.
  • Minimizes the chance of an ulcer occurring
  • By avoiding the intestinal bypass, the chances of intestinal obstruction (blockage), anemia, osteoporosis, protein deficiency and vitamin deficiency are almost eliminated
  • Can be done laparoscopically
  • No implantable devices or foreign bodies
  • Weight loss is faster than gastric band

What are the disadvantages?

  • Soft calories such as ice cream, milkshakes, etc can be absorbed and may slow weight loss.
  • This procedure does involve stomach stapling and therefore leaks, and other complications related to stapling may occur.
  • Because the stomach is removed, it is not reversible. It can be converted to almost any other weight loss procedure.
  • The stomach occasionally stretches, expanding in volume and allowing more food intake. Patients who experience this may regain some weight.
  • Since this is a newer procedure, it is less time-tested
  • It is not adjustable or reversible

Risks and Complications 

As with any surgery, there can be complications.
The most common ones include:

  • Leak and fistula 1.0%
  • Bleeding 0.5%
  • Obstruction 0.3%
  • Death 0.25%

Diet after surgery

As with all surgical weight-loss programs, it is imperative that sleeve patients adhere to a strict postoperative diet. Patients must stick to a liquid-based diet for 2 weeks after surgery; 4-6 weeks after the operation, patients graduate to a 600-800 calorie/ day solid diet. Once goal weight is achieved, usually 1-2 years after surgery, most patients can consume about 1000-1200 calories per day.

Thank you for considering CHI Memorial Metabolic and Bariatric Care. We are committed not only to a successful procedure – including gastric sleeve, gastric band, gastric bypass and revisions – but also in an aftercare program that gives you the best chance for success. 

Have questions? Call us today at (423) 899-1000 or register for a free educational seminar.