Gastric sleeve surgery is a type of weight-loss surgery (bariatric surgery). This surgery is also known as sleeve gastrectomy or vertical sleeve gastrectomy (VSG). Gastric sleeve surgery restricts your food intake, which leads to weight loss. You may lose from 50 to 90 pounds. It’s done as a laparoscopic surgery, with small incisions in the upper abdomen. Most of the left part of the stomach is removed. The remaining stomach is then a narrow tube called a sleeve. Food empties out of the bottom of the stomach into the small intestine the same way that it did before surgery. The small intestine is not operated on or changed. After the surgery, less food will make you full when eating.