ABOUT THE PROCEDURE

Roux-en-Y gastric bypass (RYGB), is the longest standing and most well studied bariatric (weight loss) procedure still in practice today. It was initially performed as open surgery as early as the 1960s. Since the late 1990s the laparoscopic approach has become standard practice.

To begin this procedure, a small section of the blood vessels attached to the right side of the stomach (lesser curvature) are divided and then a calibrated sizing tube is passed through mouth to the stomach by the anaesthetist.

A surgical stapler is positioned externally on the stomach against the internal tube. The stapler is fired in such a way that a small gastric pouch, with a volume of approximately 60mL is formed using the upper right corner of the stomach (see diagram).

The gastric staples are permanent and do no need to be removed. They are safe with MRI scanners and are too small to be detected by airport security systems.

The remaining stomach is not removed, but now is unable to receive food. This unused portion of stomach, called the bypassed stomach or remnant stomach still makes gastric acid and this acid passes to the first part of the intestine in the normal fashion.

Next, surgery is performed with a combination of staples and sutures to connect a piece of small bowel to the upper gastric pouch. This connection point is called an anastomosis. Unlike the one anastomosis gastric bypass, this loop of small bowel has been fully cut and separated.

What further differentiates the Roux-en-Y Gastric Bypass from the One Anastomosis Gastric Bypass is that a second anastomosis is performed. This second anastomosis connects the small bowel loop containing digestive juices to the small bowel loop carrying food around 50cm downstream of the first anastomosis. The total length of small intestine that is bypassed is usually between 150cm and 200cm.

RECOVERY

The surgery is performed laparoscopically (keyhole) in almost all cases with 5 small incisions in the upper abdomen. The average time in hospital after surgery is 2 nights. Office work can usually recommence after 2 weeks. Heavy work can recommence after 4 weeks.

RESULTS

This surgery results in a sensation of feeling full with much smaller quantities of food. Typically an entree size plate will provide the same feeling that a full dinner plate did before surgery. The surgery also leads to a reduction in certain hunger promoting hormones, meaning that patients notice either absence of or a decrease in the intensity of hunger between meals.

On average, patients who have a roux-en-y gastric bypass will lose around 35% of their total body weight, or between 70-80% of their excess body weight. Maximum weight loss is usually achieved between 12-18 months after surgery.

ADVANTAGES

Lowest risk of developing gastro-oesophageal reflux compared to other procedures
Bile reflux into oesophagus is generally not seen after this procedure
Potentially reversible
More weight loss than a sleeve gastrectomy (average 35% v 30% of total body weight)
More sustained weight loss compare to a sleeve gastrectomy (30% v 25% total body weight loss at 7 years)
Higher diabetes remission rate than a sleeve gastrectomy
Suitable for patients that have previously had an adjustable gastric band

DISADVANTAGES

Operation is not suitable certain patient groups such as smokers, Crohn’s disease, those on certain long-term medications, future organ transplant recipients, those with very significant bowel adhesions, or any condition requiring surveillance of the stomach or duodenum for cancer.
Longest operative time and therefore higher cost
Additional surgical risk due to second anastomosis
Internal hernia requiring emergency surgery is possible, generally seen after significant weight loss
Anastomotic ulcer formation - highest risk is in smokers.
Dumping syndrome
Nutrient deficiencies, especially if non-compliant with supplements
Remnant stomach and duodenum extremely difficult to access by endoscopy
If gallstones were to be present in the bile duct, management will be more complex
A small proportion of patients describe a chronic intermittent central abdominal pain after this procedure