Bariatric Surgery
Bariatric surgery (or weight loss surgery) includes a variety of procedures performed on people who have obesity. Weight loss is achieved by reducing the size of the stomach with a gastric band or through removal of a portion of the stomach (sleeve gastrectomy or biliopancreatic diversion with duodenal switch) or by resecting and re-routing the small intestine to a small stomach pouch (gastric bypass surgery).
The specifics of your surgery depend on your individual situation, the type of weight-loss surgery you have, and the hospital’s or doctor’s practices. Some weight-loss surgeries are done with traditional large, or open, incisions in your abdomen. Today, most types of bariatric surgery are performed laparoscopically. A laparoscope is a small, tubular instrument with a camera attached. The laparoscope is inserted through small incisions in the abdomen. The tiny camera on the tip of the laparoscope allows the surgeon to see and operate inside your abdomen without making the traditional large incisions. Laparoscopic surgery can make your recovery faster and shorter, but it’s not suitable for everyone.
Types
Procedures can be grouped in three main categories: blocking, restrictive, and mixed.
Blocking procedures
Some procedures block absorption of food, although they also reduce stomach size.
Biliopancreatic diversion
This operation is termed biliopancreatic diversion (BPD) or the Scopinaro procedure. The original form of this procedure is now rarely performed because of problems with. It has been replaced with a modification known as duodenal switch (BPD/DS). Part of the stomach is resected, creating a smaller stomach (however the patient can eat a free diet as there is no restrictive component). The distal part of the small intestine is then connected to the pouch, bypassing the duodenum and jejunum.
In around 2% of patients there is severe malabsorption and nutritional deficiency that requires restoration of the normal absorption. The malabsorptive effect of BPD is so potent that, as in most restrictive procedures, those who undergo the procedure must take vitamin and dietary minerals above and beyond that of the normal population. Without these supplements, there is risk of serious deficiency diseases such as anemia and osteoporosis.
Because gallstones are a common complication of the rapid weight loss following any type of bariatric surgery, some surgeons remove the gallbladder as a preventive measure during BPD. Others prefer to prescribe medications to reduce the risk of post-operative gallstones.
Far fewer surgeons perform BPD compared to other weight loss surgeries, in part because of the need for long-term nutritional follow-up and monitoring of BPD patients.
Jejunoileal bypass
This procedure is no longer performed. It was a surgical weight-loss procedure performed for the relief of morbid obesity from the 1950s through the 1970s in which all but 30 cm (12 in) to 45 cm (18 in) of the small bowel was detached and set to the side.
Restrictive procedures
Procedures that are restrictive shrink the size of the stomach or take up space inside the stomach, making people feel fuller when they eat less.
Vertical banded gastroplasty
In the vertical banded gastroplasty, also called the Mason procedure or stomach stapling, a part of the stomach is permanently stapled to create a smaller pre-stomach pouch, which serves as the new stomach.
Adjustable gastric band
The restriction of the stomach also can be created using a silicone band, which can be adjusted by addition or removal of saline through a port placed just under the skin. This operation can be performed laparoscopically, and is commonly referred to as a “lap band”. Weight loss is predominantly due to the restriction of nutrient intake that is created by the small gastric pouch and the narrow outlet. It is considered one of the safest procedures performed today with a mortality rate of 0.05%.
Sleeve gastrectomy
Sleeve gastrectomy, or gastric sleeve, is a surgical weight-loss procedure in which the stomach is reduced to about 15% of its original size, by surgical removal of a large portion of the stomach, following the major curve. The open edges are then attached together (typically with surgical staples, sutures, or both) to leave the stomach shaped more like a tube, or a sleeve, with a banana shape. The procedure permanently reduces the size of the stomach. The procedure is performed laparoscopically and is not reversible. It has been found to be comparable in effectiveness to Roux-en-Y gastric bypass.
Intragastric balloon
Intragastric balloon involves placing a deflated balloon into the stomach, and then filling it to decrease the amount of gastric space. The balloon can be left in the stomach for a maximum of 6 months and results in an average weight loss of 5–9 BMI over half a year. The intragastric balloon may be used prior to another bariatric surgery in order to assist the patient to reach a weight which is suitable for surgery, further it can also be used on several occasions if necessary.
Stomach folding
Basically, the procedure can best be understood as a version of the more popular gastric sleeve or gastrectomy surgery where a sleeve is created by suturing rather than removing stomach tissue thus preserving its natural nutrient absorption capabilities. Gastric plication significantly reduces the volume of the patient’s stomach, so smaller amounts of food provide a feeling of satiety.
Mixed procedures
Mixed procedures apply block and restrict at the same time.
Gastric bypass surgery
A common form of gastric bypass surgery is the Roux-en-Y gastric bypass, designed to reduce the amount of food a person is able to eat by cutting away a part of the stomach. Gastric bypass is a permanent procedure that helps patients by changing how the stomach and small intestine handle the food that is eaten to achieve and maintain weight loss goals. After the surgery, the stomach will be smaller. A patient will feel full with less food.
A factor in the success of any bariatric surgery is strict post-surgical adherence to a healthy pattern of eating.
There are certain patients who cannot tolerate the malabsorption and dumping syndrome associated with gastric bypass. In such patients, although earlier considered to be an irreversible procedure, there are instances where gastric bypass procedure can be partially reversed.
Sleeve gastrectomy with duodenal switch
A variation of the biliopancreatic diversion includes a duodenal switch. The part of the stomach along its greater curve is resected. The stomach is “tubulized” with a residual volume of about 150 ml. This volume reduction provides the food intake restriction component of this operation. This type of gastric resection is anatomically and functionally irreversible. The stomach is then disconnected from the duodenum and connected to the distal part of the small intestine. The duodenum and the upper part of the small intestine are reattached to the rest at about 75–100 cm from the colon.
Implantable gastric stimulation
This procedure where a device similar to a heart pacemaker is implanted by a surgeon, with the electrical leads stimulating the external surface of the stomach. Electrical stimulation is thought to modify the activity of the enteric nervous system of the stomach, which is interpreted by the brain to give a sense of satiety, or fullness. Early evidence suggests that it is less effective than other forms of bariatric surgery.
