Surgery as a Treatment for Obesity

A Lesson in Anatomy

Below is an explanation of the structure and function of the parts of the digestive system (GI) that participate in the surgery:

• The esophagus is a hollow muscular tube that connects the back of the mouth with the stomach. The stomach is a muscular organ that stores food, digestion begins and can extend to the size of a soccer ball. The stomach begins the process of digestion by converting solid foods into liquids before being pushed into the intestine.
• The stomach opens in the first part of the small intestine called the duodenum. The doudeno comes from a Latin word that means 12 and in fact, it is 12 inches long in an adult. Even though the duodenum is the shortest part of the small intestine, it is very important because it receives the secretions of the liver and pancreas, which are necessary for digestion.
• The second part of the small intestine is called the jejunum, and it is about 10 feet long. The Ileon, the third and last part of the small intestine, ends in the colon or large intestine. The total length of the small intestine is approximately 20 feet. Most nutrients (for example, iron, glucose, calcium, and vitamins) are absorbed in the small intestine.
• The colon, or large intestine, is approximately 6 feet long. Its main function is to absorb the liquids from the stool and store it until it is expelled in the form of feces.

Types of Surgery for Weight Loss

Surgical procedures for the treatment of obesity can be divided into three general categories:

1. The malabsorptive procedures
2. Restrictive procedures
3. The combination of malabsorptive/restrictive procedures

In the mid-1970s, malabsorption procedures, such as jejunal-ileal bypass procedures, became popular in the treatment of obesity. In 1983, it was recognized that the complications associated with this bridge (bypass) were too frequent and serious as well. The procedure was therefore abandoned and is no longer recommended. A modern variant called biliopancreatic diversion and the duodenal crossover is being performed in some centers for selected patients with very severe obesity.

Restrictive procedures also have a history of modifications that come in many variants. Although these procedures have fewer metabolic complications, it is still unclear whether they are successful in creating long-term sustainable weight loss. This is mainly due to the nature of the stomach that is an extensible organ and adapts to any restrictions imposed inside. Restrictive operations include the adjustable gastric band (Lap-Band) and Vertical Gastrectomy (gastric sleeve).

The Roux-en-Y gastric bypass is the most common weight-loss operation performed in the United States and worldwide. It can be considered as a restrictive procedure, however, there is a component of malabsorption because food does not pass to most of the stomach and the first part of the small intestine.

Open and Laparoscopic Procedures

Many patients may have their surgery performed by laparoscopy attracting small incisions, cameras, and long instruments. This usually involves 5 to 6 incisions of an inch each. Laparoscopic procedures may be limited by high body mass index, liver size, abdomen anatomy, or technical limits of instruments and equipment. Therefore, there may be cases in which a procedure is initiated via laparoscopic surgery, but it must be completed through an open incision.

Patients with previous abdominal surgery, large abdominal wall hernias, heart disease, or high body mass index may have their operation through an open incision. These conditions can make laparoscopic surgery technically difficult or excessively long, increasing the risk of organ injury, blood clot, heart attack, and other complications. These incisions are vertical, usually 6 to 8 inches long in the upper abdomen.

There is no difference in weight loss outcomes between patients with laparoscopic surgery compared to patients with operations. Open operations have a slightly higher rate of wound problems (i.e., 5% to 10% chance of wound infection or a hernia), while laparoscopic operations may have a slightly higher risk of bleeding.

M.D. Henry Calixto Alemán Zamora
Bariatric Surgeon