How Does Bariatric Surgery Work?
Bariatric surgery promotes weight loss by restricting food intake and, in some procedures, altering the digestive process. As with other treatments for obesity, the best results are achieved when combined with healthy eating behaviors and regular physical activity. If bariatric surgery is the right choice for you, your surgeon will discuss with you the procedures offered at the Center for Bariatric Surgery and will explain which would achieve the best outcomes for your individual circumstance.
What Are the Requirements for Bariatric Surgery?
Generally, candidates for surgery must have either a body mass index (BMI) equal to or greater than 40 if they have no additional health conditions related to obesity, or a BMI of equal to or greater than 35 if they have additional health conditions related to obesity.
- Healthy enough to undergo a major operation
- Failed attempts at medical weight loss
- Absence of drug and alcohol problems
- No uncontrolled psychological conditions
- Consensus by multi-disciplinary team
- Understands surgery and risks
What is laparoscopy?
The preferred methods for bariatric surgery at the Center for Bariatric Surgery involve laparoscopy (also known as minimally invasive surgery), a surgical technique in which a high-definition camera and very fine surgical instruments are placed through small incisions, instead of the standard large incisions. The image is then viewed on a video monitor by highly trained surgeons as they perform the procedure using the specialized instruments.
Eliminating the need for a large incision, laparoscopy results in less tissue damage, less blood loss, shorter hospitalization, a faster recovery, and fewer complications than open operations. The Miriam Hospital's state-of-the-art operating rooms and staff provide patients with the best care possible using laparoscopic techniques.
What is adjustable gastric banding?
Gastric banding, usually done laparoscopically, is a less invasive and the only adjustable and reversible obesity surgery available. During this procedure, surgeons place an inflatable silicone band around the upper stomach to create a new, tiny pouch that limits the amount of food that can be consumed and slows its progression into the stomach and intestines. The patient feels full sooner and satisfied with smaller amounts of food, ultimately losing up to 40 to 60 percent of his or her excess weight over three years.
This procedure usually requires a one-day hospital stay, and normal activities can be resumed in two to four weeks.
The band itself is adjustable by adding or removing fluid from the band's interior through a small port that is placed beneath the patient's skin. Adjustments can be made as necessary in the surgeon's office, where the surgeon can adjust the band via the port with minimal discomfort to the patient. If the band ever needs to be removed, the stomach will return to its original form and function.
What is vertical sleeve gastrectomy?
This relatively new surgery also restricts food intake after surgery and results in weight loss similar to banding surgery. In this operation, 70 percent of the stomach is removed. The new tube-shaped stomach limits food intake soon after surgery and results in improvement in a variety of medical conditions.
In some cases, a patient's morbid obesity is so pronounced that the patient would benefit from a two-stage process in order to lose several hundred pounds. Sleeve gastrectomy is usually performed as the first stage. A second surgery is offered to reach the goal weight for the patient when he or she reaches a safe weight, usually after a few months.
What is Roux-en-Y gastric bypass?
If a patient requires even greater weight loss than banding techniques produce, a gastric bypass operation is considered. Gastric bypass procedures reduce absorption of food, in addition to restricting food intake. Patients who have bypass operations generally lose 70 percent of their excess weight within one and a half years.
In Roux-en-Y gastric bypass, the most common bariatric procedure, a small stomach pouch is created by stapling to separate it from the rest of the stomach. Then, a section of the small intestine is attached to the new pouch to allow food to bypass the first portion of the small intestine to reduce calorie and nutrient absorption. The limited quantity of food, combined with reduced absorption of calories, results in faster and perhaps more pronounced weight loss than is normally achieved by the gastric banding procedure.
This procedure usually requires a two- to three-day hospital stay, and normal activities can be resumed in four to five weeks. Patients with type 2 diabetes often see immediate improvement in their diabetes after this surgery.
What is a duodenal switch?
Biliopancreatic diversion with duodenal switch (BPD/DS), most often known as a duodenal switch, is a weight-loss surgery that reduces a patient’s ability to absorb calories, vitamins, and minerals. Duodenal switch patients can lose more weight than with other surgical methods like gastric bypass or sleeve gastrectomy. However, much like gastric bypass and sleeve gastrectomy, there are complications that are unique to this procedure.
Doctors generally recommend BPD/DS for people who are severely obese, with a body mass index (BMI) of 50 or great or a BMI of 40 or greater with serious type 2 diabetes and other serious health problems.
Other health problems include:
- Sleep apnea
- Heart disease
- Lung disease
- High blood pressure
- High cholesterol
- Nonalcoholic fatty liver disease
During a duodenal switch procedure, the surgeon removes the left portion of the stomach to limit food intake and then “switches” the small intestine to alter the digestion process and limit food absorption. This approach works in three ways:
- It limits stomach capacity.
- It reroutes food away from the upper part of the small intestine, which reduces how many calories and nutrients the body absorbs.
- It changes the way food mixes with bile and pancreatic enzymes – prompting additional weight loss.
This weight loss option shows greater results than gastric bypass or sleeve gastrectomy with 70% or greater excess weight loss at a five year follow-up, with favorable changes in gut hormones which regulate appetite. It is also effective against Type 2 diabetes. However, duodenal switch is the longest operation and may carry a higher risk of post-operative complications. Additionally, due to the reduced ability to absorb certain vitamins and minerals there is a risk of developing nutritional deficiencies after surgery.
It is important to discuss all options with your surgeon to identify the best choice for you based on your specific weight and health needs.