How Long Does Gastric Sleeve Surgery Take? Gastric sleeve surgery is a surgery to lose weight. Also known as sleeve gastrectomy or vertical sleeve gastrectomy (VSG). Gastric surgery reduces food intake, which leads to weight loss. You can lose 50 to 90 pounds. We will learn about how long does gastric sleeve surgery take. It is performed as a laparoscopic surgery, with small incisions in the upper abdomen. Most of the left side of the stomach is removed. The rest of the stomach is then a narrow tube called a sleeve.