Bariatric surgery (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).
Long-term studies show the procedures cause significant long-term loss of weight, recovery from diabetes, improvement in cardiovascular risk factors, and a mortality reduction from 40% to 23%. The U.S. National Institutes of Health recommends bariatric surgery for obese people with a body mass index (BMI) of at least 40, and for people with BMI of at least 35 and serious coexisting medical conditions such as diabetes. However, research is emerging that suggests bariatric surgery could be appropriate for those with a BMI of 35 to 40 with no comorbidities or a BMI of 30 to 35 with significant comorbidities. The most recent American Society for Metabolic & Bariatric Surgery guidelines suggest the position statement on consensus for BMI as an indication for bariatric surgery. The recent guidelines suggest that any patient with a BMI of more than 30 with comorbidities is a candidate for bariatric surgery.
A National Institute of Health symposium held in 2013 that summarized available evidence found a 29% mortality reduction, a 10-year remission rate of Type 2 Diabetes of 36%, fewer cardiovascular events, and a lower rate of diabetes-related complications in a long-term, non-randomized, matched intervention 15-20 year follow-up study, the Swedish Obese Subjects Study. The symposium also found similar results from a Utah study using more modern gastric bypass techniques, though the follow-up periods of the Utah studies are only up to 7 years. While randomized controlled trials of bariatric surgery exist, they are limited by short follow-up periods.
Procedures can be grouped in three main categories: blocking, restricting, and mixed. Standard of care in the United States and most of the industrialized world in 2009 is for laparoscopic as opposed to open procedures. Future trends are attempting to achieve similar or better results via endoscopic procedures.
Some procedures block absorption of food, although they also reduce stomach size.
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.
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.
A study on humans was done in Chile using the same technique however the results were not conclusive and the device had issues with migration and slipping. A study recently done in the Netherlands found a decrease of 5.5 BMI points in 3 months with an endoluminal sleeve.
Procedures that are restrictive shrink the size of the stomach or take up space inside the stomach, making people feel more full 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, 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 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 is approved in Australia, Canada, Mexico, India, United States (received FDA approval in 2015) and several European and South American countries. 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.
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. The procedure is producing some significant results that were published in a recent study in Bariatric Times and are based on post-operative outcomes for 66 patients (44 female) who had the gastric sleeve plication procedure between January 2007 and March 2010. Mean patient age was 34, with a mean BMI of 35. Follow-up visits for the assessment of safety and weight loss were scheduled at regular intervals in the postoperative period. No major complications were reported among the 66 patients. Weight loss outcomes are comparable to gastric bypass.
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, is being studied in the USA. 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.
Eating after bariatric surgery:
Immediately after bariatric surgery, the patient is restricted to a clear liquid diet, which includes foods such as clear broth, diluted fruit juices or sugar-free drinks and gelatin desserts. This diet is continued until the gastrointestinal tract has recovered somewhat from the surgery. The next stage provides a blended or pureed sugar-free diet for at least two weeks. This may consist of high protein, liquid or soft foods such as protein shakes, soft meats, and dairy products. Foods high in carbohydrates are usually avoided when possible during the initial weight loss period.
Post-surgery, overeating is curbed because exceeding the capacity of the stomach causes nausea and vomiting. Diet restrictions after recovery from surgery depend in part on the type of surgery. Many patients will need to take a daily multivitamin pill for life to compensate for reduced absorption of essential nutrients. Because patients cannot eat a large quantity of food, physicians typically recommend a diet that is relatively high in protein and low in fats and alcohol.
Benefits of Bariatric Surgery:
Gastric bypass surgery is done to help you lose excess weight and reduce your risk of potentially life-threatening weight-related health problems, including:
* Gastroesophageal reflux disease
* Heart disease
* High blood pressure
* Severe sleep apnea
* Type 2 diabetes
Gastric bypass and other weight-loss surgeries are typically done only after you’ve tried to lose weight by improving your diet and exercise habits.
As with any major surgery, gastric bypass and other weight-loss surgeries pose potential health risks, both in the short term and long term.
Risks associated with the surgical procedure can include:
* Excessive bleeding
* Adverse reactions to anesthesia
* Blood clots
* Lung or breathing problems
* Leaks in your gastrointestinal system
* Death (rare)
Longer term risks and complications of weight-loss surgery vary depending on the type of surgery. They can include:
* Bowel obstruction
* Dumping syndrome, causing diarrhea, nausea or vomiting
* Low blood sugar (hypoglycemia)
* Stomach perforation
* Death (rare)
When weight-loss surgery doesn’t work:
Gastric bypass and other weight-loss surgeries don’t always work as well as you might have hoped. For one thing, although rare, something during or after the procedure itself may go wrong. For instance, the adjustable band may fail to work properly. If a weight-loss procedure doesn’t work right or stops working, you may not lose weight and you may develop serious health problems. Keep all of your scheduled follow-up appointments after weight-loss surgery. If you notice that you aren’t losing weight or you develop complications, see your doctor immediately. Your weight loss can be monitored and factors potentially contributing to your lack of weight loss evaluated.
It’s also possible to not lose enough weight or to regain weight after any type of weight-loss surgery, even if the procedure itself works correctly. This weight gain can happen if you don’t follow the recommended lifestyle changes. To help avoid regaining weight, you must make permanent healthy changes in your diet and get regular physical activity and exercise. If you frequently snack on high-calorie foods, for instance, you may have inadequate weight loss.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.