Gastric Bypass
Gastric Bypass
Key Points
Initial weight loss is greater than with other treatments.
Major surgery with greater risks of complication.
Hospital stay between 3-6 nights.
Non-reversible procedure.
Nutrient supplements will be required.
Gastric Bypass
There are several varieties of bypass, but all involve the creation of a small stomach pouch to restrict food intake and construction of bypasses of the duodenum and other segments of the small intestine to cause malabsorption (decreased ability to absorb calories and nutrients from food). Thus unlike the adjustable gastric band which is a restrictive procedure only, gastric bypass is both restrictive and malabsorptive.
Types of gastric bypass operations
Though there are a number of variations, two of the most commonly performed bypass procedures are the Roux-en-Y gastric bypass (RGB) and Biliopancreatic Diversion (BPD). These - and their variations - are performed as keyhole procedures.
Roux-en-Y gastric bypass (RGB)
First a small pouch is created by stapling off the upper part of the stomach. This restricts the amount of food you can eat. Next a carefully measured length of small intestine is divided, one end is connected to the newly formed pouch, creating a channel for food to travel down, bypassing the now redundant stomach and duodenum (beginning of the small intestine).
Gastric juices, (containing essential enzymes for absorption of calories and nutrients from food) are introduced to the food by rejoining the small intestine, creating a Y shaped bypass.
Biliopancreatic Diversion (BPD)
In this more complicated version, portions of the stomach are removed and the small pouch that remains is connected directly to the final segment of the small intestine. This means that most of the small intestine is bypassed, resulting in substantial reductions in calorie and nutrient absorption.
How does the gastric bypass work?
The gastric bypass procedure alters food digestion by reducing the stomach in size and re-routing the small intestine. A combination of both takes advantage of restriction and malabsorption resulting in a reduction of calories absorbed.
The gastric bypass works by making the stomach much smaller so that you feel fuller sooner. It also works by curbing the appetite as the food goes quickly into the small intestine, chemical messages are sent to the brain telling the satiety centres that food is present.
Surgery will also improve the patients sense of self control and helps many avoid sugary/fatty foods due to ˜dumping syndrome'.
The gastric bypass benefit?
The gastric bypass is a one off laparoscopic surgical procedure that should not require any further interventions. Excellent weight loss results are achieved by restricting the capacity of food eaten at one time - so fewer calories are absorbed.
Weight loss maintenance can be achieved by your commitment to lifestyle changes, physical activity and our support programmes.