Gastric Restrictive Procedure - Vertical Banded Gastroplasty
Vertical Banded Gastroplasty (VBG) is a purely restrictive procedure. In this procedure the upper stomach near the esophagus is stapled vertically for about 2-1/2 inches (6 cm) to create a smaller stomach pouch. The outlet from the pouch is restricted by a band or ring that slows the emptying of the food and thus creates the feeling of fullness.
Advantages
Malabsorptive Procedures - Biliopancreatic Diversion
While these operations also reduce the size of the stomach, the stomach pouch created is much larger than with other procedures. The goal is to restrict the amount of food consumed and alter the normal digestive process, but to a much greater degree. The anatomy of the small intestine is changed to divert the bile and pancreatic juices so they meet the ingested food closer to the middle or the end of the small intestine.With the three approaches discussed below, absorption of nutrients and calories is also reduced, but to a much greater degree than with previously discussed procedures. Each of the three differs in how and when the digestive juices (i.e., bile) come into contact with the food.
Since food bypasses the duodenum, all the risk considerations discussed in the gastric bypass section regarding the malabsorption of some minerals and vitamins also apply to these techniques, only to a greater degree.
Biliopancreatic Diversion (BPD)
BPD removes approximately 3/4 of the stomach to produce both restriction of food intake and reduction of acid output. Leaving enough upper stomach is important to maintain proper nutrition. The small intestine is then divided with one end attached to the stomach pouch to create what is called an "alimentary limb." All the food moves through this segment, however, not much is absorbed. The bile and pancreatic juices move through the "biliopancreatic limb," which is connected to the side of the intestine close to the end. This supplies digestive juices in the section of the intestine now called the "common limb." The surgeon is able to vary the length of the common limb to regulate the amount of absorption of protein, fat and fat-soluble vitamins.
Extended (Distal) Roux-en-Y Gastric Bypass (RYGBP-E)
RYGBP-E is an alternative means of achieving malabsorption by creating a stapled or divided small gastric pouch, leaving the remainder of stomach in place. A long limb of the small intestine is attached to the stomach to divert the bile and pancreatic juices. This procedure carries with it fewer operative risks by avoiding removal of the lower 3/4 of the stomach. Gastric pouch size and the length of the bypassed intestine determine the risks for ulcers, malnutrition and other effects.
Biliopancreatic Diversion with "Duodenal Switch"
This procedure is a variation of BPD in which stomach removal is restricted to the outer margin, leaving a sleeve of stomach with the pylorus and the beginning of the duodenum at its end. The duodenum, the first portion of the small intestine, is divided so that pancreatic and bile drainage is bypassed. The near end of the "alimentary limb" is then attached to the beginning of the duodenum, while the "common limb" is created in the same way as described above.
Advantages
Combined Restrictive & Malabsorptive Procedure -
Gastric Bypass Roux-en-Y
In recent years, better clinical understanding of procedures combining restrictive and malabsorptive approaches has increased the choices of effective weight loss surgery for thousands of patients. By adding malabsorption, food is delayed in mixing with bile and pancreatic juices that aid in the absorption of nutrients. The result is an early sense of fullness, combined with a sense of satisfaction that reduces the desire to eat.
According to the American Society for Bariatric Surgery and the National Institutes of Health, Roux-en-Y gastric bypass is the current gold standard procedure for weight loss surgery. It is one of the most frequently performed weight loss procedures in the United States. In this procedure, stapling creates a small (15 to 20cc) stomach pouch. The remainder of the stomach is not removed, but is completely stapled shut and divided from the stomach pouch. The outlet from this newly formed pouch empties directly into the lower portion of the jejunum, thus bypassing calorie absorption. This is done by dividing the small intestine just beyond the duodenum for the purpose of bringing it up and constructing a connection with the newly formed stomach pouch. The other end is connected into the side of the Roux limb of the intestine creating the "Y" shape that gives the technique its name. The length of either segment of the intestine can be increased to produce lower or higher levels of malabsorption.
Advantages
Laparoscopic or Minimally Invasive Surgery
For the last decade, laparoscopic procedures have been used in a variety of general surgeries. Many people mistakenly believe that these techniques are still "experimental." In fact, laparoscopy has become the predominant technique in some areas of surgery and has been used for weight loss surgery for several years. Although few bariatric surgeons perform laparoscopic weight loss surgeries, more are offering patients this less invasive surgical option whenever possible.
When a laparoscopic operation is performed, a small video camera is inserted into the abdomen. The surgeon views the procedure on a separate video monitor. Most laparoscopic surgeons believe this gives them better visualization and access to key anatomical structures.
The camera and surgical instruments are inserted through small incisions made in the abdominal wall. This approach is considered less invasive because it replaces the need for one long incision to open the abdomen. A recent study shows that patients having had laparoscopic weight loss surgery experience less pain after surgery resulting in easier breathing and lung function and higher overall oxygen levels. Other realized benefits with laparoscopy have been fewer wound complications such as infection or hernia, and patients returning more quickly to pre-surgical levels of activity.
Laparoscopic procedures for weight loss surgery employ the same principles as their "open" counterparts and produce similar excess weight loss. Not all patients are candidates for this approach, just as all bariatric surgeons are not trained in the advanced techniques required to perform this less invasive method. The American Society for Bariatric Surgery recommends that laparoscopic weight loss surgery should only be performed by surgeons who are experienced in both laparoscopic and open bariatric procedures.