Sleeve gastrectomy is also known as gastric sleeve surgery or vertical sleeve gastrectomy (VSG). During this operation, nearly 90% of the stomach is removed. Stomach function remains normal because the key components of the stomach are preserved. Anatomy is not altered in any other way and there is no intestinal bypass.
How Sleeve Gastrectomy Surgery Works
The stretchy upper and outer 90% of the stomach is removed, leaving a small, vertically oriented tubular stomach. The remaining stomach is shaped like a banana or “sleeve” and is approximately 6 inches long and one-half inch in diameter. Stomach capacity is reduced from about a quart (1,000 ml) to roughly 4 ounces (120 ml). Depending on the size of the tube that is created, patients generally report feeling full after eating about 4 ounces of solid food.
The important structural elements of the stomach — the antrum, the pylorus and the nerves that control stomach function — are preserved. The result is a much smaller stomach that functions similarly to a normal one. This allows patients to enjoy a relatively normal diet (albeit in much smaller quantities) without negative side effects such as “dumping” syndrome. Weight loss is achieved by restricting the amount of food that can be consumed. The gastric sleeve procedure involves no intestinal bypass or malabsorption of nutrients.
Removal of the outer portion of the stomach almost completely removes the tissue that produces ghrelin, the hunger-stimulating hormone. Consequently, patients typically report a significant decrease in hunger and food consumption. Studies have reported ghrelin levels remain low in sleeve patients throughout a five-year follow-up period. 1
Gastric Sleeve Surgery Outcomes
Approximately 60% excess weight loss (EWL) has been reported. 2,3 Excess weight is the amount of weight over what is considered the “ideal body weight” for a person’s height.
Improvement / Resolution of Comorbidities
Improvement and/or resolution in all major coexisting medical conditions or diseases, including type 2 diabetes, sleep apnea, hypertension and high cholesterol, has been documented.
Compared to gastric bypass, this procedure that creates a weight loss surgery sleeve is much simpler. There also is very little risk of “dumping” syndrome, which occurs when a patient who has had gastric bypass consumes sugar or carbohydrates or eats too quickly. Dumping syndrome causes nausea, cramping, diarrhea, sweating, vomiting and heart palpitations. The surgical sleeve does not bypass the pyloric valve, allowing for a more natural emptying of solid foods from the stomach. It also involves no intestinal bypass or malabsorption of nutrients, and thus there is a much lower chance of nutrient or vitamin deficiency. Other benefits include being able to eat most food (just in small amounts), decreased hunger, a low risk of ulcers, and eligibility to undergo the procedure even with anemia, Crohn’s disease or other conditions.
While complications involving the gastric sleeve procedure are rare, it is possible that some individuals may encounter them. Risks include leakage from the staple line, strictures, bleeding, chronic nausea and vomiting, blood clots, heartburn, nutrient or vitamin deficiency, gallstones, acid reflux, excess skin, inadequate weight loss, weight regain or even death. The procedure is not reversible. You also may find certain foods don’t agree with you after surgery.
This is a pill-friendly operation. Aspirin and other NSAIDS are well tolerated.
To be a good candidate for bariatric surgery, you will need either a BMI greater than 40 or a BMI in the 35-39.9 range accompanied by hypertension, type 2 diabetes, sleep apnea, fatty liver disease or hyperlipidemia. Typically, this means you will be 100 pounds or more above your ideal weight.
Follow-Up After Surgery
Because this is a life-changing procedure, it’s normal to encounter some challenges afterward. With that in mind, you will have frequent follow-up appointments. They typically are scheduled for two weeks, three months, six months and one year after surgery. At these appointments, you may have blood work done and undergo laboratory testing and other exams. You will also need to take vitamins and supplements for the rest of your life.
Bohdjalian A, Langer FB, Shakeri-Leidenmuhler S, et al. Sleeve gastrectomy as sole and deﬁnitive bariatric procedure: 5-year results for weight loss and ghrelin. Obes Surg. 2010;20:535–540.e24 ASMBS Clinical Issues Committee / Surgery for Obesity and Related Diseases 8 (2012).