A sleeve gastrectomy is a surgical procedure in which the stomach is reduced to around 25 per cent of its former volume. An irreversible intervention, a large portion of the stomach is removed by the surgeon, who generally does this via laparoscopy. During laparoscopy, the surgeon will employ an instrument called an endoscope, which is a tube with a camera at the end. This is inserted into the abdomen through a small incision and it allows the surgeon to see the internal organs and remove tissue when necessary.
The stomach is an asymmetrical organ that bulges to one side – usually the left – and this bulge is known as the greater curvature. The other side is known as the lesser curvature. During a sleeve gastrectomy, much of the greater curvature is removed, so that a tube, or sleeve, remains. Doing this greatly decreases the size of the stomach, and the effect is permanent, although it could stretch to some degree in the following years.
The operation was developed as a modification to another procedure known as the duodenal switch, which was a type of modification to the gastric organs to reduce their capacity. The duodenal switch was often used as a method of restricting food absorption and increasing weight loss. Sometimes the sleeve gastrectomy was conducted as the first stage of a gastric bypass on severely obese patients. In a gastric bypass, the stomach is reduced to a pouch, which decreases the ability of the rest of the stomach and parts of the small intestine to absorb food.
In many patients, a sleeve gastrectomy is as effective a tool for losing weight as a gastric bypass. Today, the sleeve gastrectomy is a popular technique for reducing weight, particularly in Asia and North America.
During a sleeve gastrectomy, the stomach is cut along its length, from the top of the organ, known as the fundus, which is close to the base of the oesophagus, where food enters the stomach. The other end of the cut or section is near the pylorus, where food leaves the stomach and enters the duodenum, the first part of the small intestine. The surgeon may sometimes begin cutting the stomach near the pylorus and work upwards. When the section of the stomach has been cut away, the edges are stapled or sewn together around the endoscope to form a tube. A sleeve gastrectomy is usually performed under general anaesthetic, and afterwards patients will have a much smaller stomach. This may resemble a banana in shape, and will act as a physical deterrent to eating large amounts. The remains of the stomach could hold in the region of 150ml of chewed food.
Keyhole surgery is often favoured for a sleeve gastrectomy, as the recovery time for the operation is reduced and patients may suffer less pain and have to spend less time in hospital. Alternatively, the abdomen can be cut open, which is also known as an open sleeve gastrectomy, and this will leave a much larger scar.
Sleeve gastrectomies have been enthusiastically embraced by some associations of surgeons and physicians who treat the morbidly obese. The procedure has been performed on children and teenagers as well, and has been reported to have had successful results.