Gastric Sleeve Surgery, also known as Gastric Sleeve Resection or Vertical Sleeve Gastrectomy (VSG), is a restrictive type of weight loss surgery that permanently reduces the size of the stomach. It promotes weight loss by limiting food intake and lessening the sensation of hunger; it does not involve intestinal rerouting or food malabsorption.


The gastric sleeve procedure has been gaining attention in recent years as an effective bariatric option, yet it is not a completely new type of surgery. It has been performed by bariatric surgeons for quite some time, but usually as the first part of a two-stage operation. Originally, the gastric sleeve surgery was designed to be followed up by a second procedure, either gastric bypass or duodenal switch surgery, at a later date. The purpose of the two-stage approach is to make weight loss surgery safer for high-risk patients, particularly individuals with a high body mass index (BMI greater than 50 to 60) and/or with health conditions that make them unacceptable candidates for a single, combined restrictive and malabsorptive surgery.


In recent years, many bariatric surgeons have begun to perform gastric sleeve surgery as a stand-alone weight loss procedure. With this new approach, the stomach pouch is usually made smaller than in duodenal switch patients. While long term results are not yet available, short term weight loss results have been primarily favorable, especially in low BMI patients (BMI 35 to 45).


During gastric sleeve surgery, the bariatric surgeon removes approximately 60 to 80% of the stomach along the greater curvature, leaving only a small tube, or “sleeve” for the new stomach pouch that extends from the natural stomach opening to the natural stomach outlet (pyloric valve). The procedure helps to limit eating by reducing the overall size of the stomach and control hunger by removing the part of the stomach that produces the hunger-stimulating hormone Ghrelin.


The cutaway part of the stomach is removed from the body and not left in place as with gastric bypass surgery, therefore the stomach reduction is permanent and the gastric sleeve procedure is not reversible. Overall, it is a less complicated operation than either gastric bypass or duodenal switch surgery, since the pyloric valve and small intestine are left intact. Also, the gastric sleeve does not involve implanting a medical device into the body in order to restrict eating as with adjustable gastric banding surgery.


Expected Weight Loss Results


Patients who undergo the gastric sleeve procedure as a first stage procedure are typically expected to lose approximately 30 to 50% of their excess body weight during the following six to twelve months before continuing with the second surgery. This initial weight loss will make it safer to proceed with the second-stage of the process, either gastric bypass or duodenal switch surgery, which involves rerouting the small intestine. The timing of the second procedure will depend on the rate of weight loss following the gastric sleeve surgery.


Short term results show that gastric sleeve patients who have had the stand-alone procedure can expect to achieve a 60 to 70% excess weight loss at 2 years. Long term results are not yet available. If weight loss is insufficient following gastric sleeve surgery, a malabsorptive weight loss procedure such as the duodenal switch may be performed in order to promote further weight loss.


Patient Considerations for Gastric Sleeve Surgery


Safer option for individuals with BMI greater than 60 to undergo two-stage process of gastric sleeve followed up with duodenal switch or gastric bypass after partial weight loss
Option for patients concerned about long-term side effects of weight loss surgery that involves rerouting and bypassing a portion of the small intestine, such as intestinal obstruction, ulcers, anemia, osteoporosis, protein deficiency, and vitamin deficiency
Restrictive weight loss option for patients who are not comfortable having a medical device implanted into their body as with the LAP-BAND or REALIZE Band
Surgical weight loss option for patients with health problems or complex medical issues that may prevent them from having other types of weight loss surgery, such as anemia, Crohn’s disease, anti-inflammatory drug use, or extensive prior surgery
Revision option for gastric band patients experiencing problems with their band but who do not want to convert to a bypass type of operation
Advantages of Gastric Sleeve Weight Loss Surgery


Promotes weight loss by restricting amount of food that can be eaten at any one time
Reduces hunger since it removes the part of the stomach that produces the hunger stimulating hormone ghrelin
Digestion occurs normally as the digestive system is not altered
Does not cause malabsorption or nutritional deficiencies as it does not involve rerouting or bypassing the small intestine
Less chance of developing ulcers than with gastric bypass surgery
Dumping syndrome not likely to occur as the stomach outlet (pyloric valve) remains intact, unlike gastric bypass surgery
Less complicated procedure than gastric bypass or duodenal switch surgery
Can usually be performed laparoscopically on extremely obese patients
Does not require a gastric band being implanted into the body
Does not require adjustments or fills as with a LAP-BAND or REALIZE Band
Safer than a combined restrictive/malabsorptive weight loss surgery for patients who have many health problems
May be converted to gastric bypass or duodenal switch if necessary for additional weight loss
Expected excess weight loss for stand-alone procedure is 60 to 70% at two years
Disadvantages of Gastric Sleeve Weight Loss Surgery


As it is a purely restrictive weight loss procedure, inadequate weight loss or weight regain is more likely than with a procedure involving intestinal bypass
With time, new smaller stomach pouch may stretch (also occurs with gastric bypass surgery)
Although the gastric sleeve helps control hunger and limit amount of food that can be eaten at any one time, weight loss will not occur without a healthy, low-calorie diet and regular exercise (same as with other purely restrictive procedures such as LAP-BAND and REALIZE Band)
If performed as the first part of a two-stage process, a second malabsorptive weight loss surgery such as the duodenal switch will need to be performed at a later time
The surgery is not reversible as a portion of the stomach is permanently removed
Leaks or bleeding may occur along the stomach stapling edge
Procedure may not be covered by some insurance companies
All surgery and anesthesia involves some level of risk including bleeding, blood clots, infection, pneumonia, or complications
Lack of published data for long-term weight loss results
Gastric Sleeve Weight Loss Surgery - Diet Restrictions


The gastric sleeve procedure will help a person control their hunger and limit the amount of food they can eat at any one time. As with all surgical weight loss programs, however, weight loss ultimately depends on adopting a new lifestyle, healthy diet, and regular exercise. The surgery itself does not require many food restrictions as the stomach continues to function normally, but for weight loss to occur high-calorie and high-fat foods and drinks must be avoided and daily calories must be limited. Many bariatric surgeons recommend eating five small, healthy meals a day with no snacking in-between meals.


Following surgery, patients will need to follow a liquid diet for about two weeks while the body heals. The diet will slowly progress from soft to solid foods. At about 4 to 6 weeks after surgery, most patients will usually be able to eat a regular solid diet. During the first 1 to 2 years after surgery, when most weight loss is expected to occur, the diet is limited to 600 to 800 calories a day. Once goal weight is achieved, most patients are able to eat about 1000 to 1200 calories a day.