The principal indication for the surgery is the same and the surgical risk tends to the same.  Various surgeons choose various types of bypasses to suit different circumstances.

Both forms of gastric bypass practiced by our team involve very much similar principles of reducing the gastric volume from a large balloon-type volume to a narrow reduced volume gastric tube that is particularly non-compliant – in other words, it does not distend and has a very limited capacity.  In both operations, the reduced gastric pouch then empties into a limb of small bowel, and hence the term gastric bypass. Important to understand, that the stomach is not removed it is simply detached and continuity maintained by the bowel join-up with the small bowel.

As a rule of thumb, Dr Hopkins is more likely to take on the gastric bypass single anastomosis in the setting of first-time surgery, and the Roux-en-Y gastric bypass is more likely to be used in the revisional operation, i.e. where previous gut surgery or weight loss surgery has been undertaken.

Laparoscopic Roux-en-Y Gastric Bypass

The laparoscopic Roux-en-Y gastric bypass is often referred to the as the “gold standard” because it is the oldest version of the surgery.  The Roux-en-Y is a description given to how the small bowel empties the reduced gastric pouch.  The concept in the Roux-Y is to divert the digestive juices from the bile and the pancreas away from the gastric pouch to prevent exposure to the upper part of the gut.  In this setting, the diversion is set per the diagram so that the bowel is connected to itself (the small bowel) but lower down and away from the gastric pouch.  The Roux-en-Y gastric bypass obviously has both upsides and downsides.  Very importantly, the upside is that it prevents reflux of the digestive juices into the pouch, the downside is that it represents an extra join-up in surgery and that that extra join-up can be responsible for complications in the post-operative period in just days but also in the years that ensue.  Gastric bypasses have a risk of gut herniation and torsion and these issues can certainly represent indications for further surgery down the track.

Single Anastomosis Gastric Bypass (Single Loop Gastric Bypass, Mini Gastric Bypass)

This is a procedure which has evolved from the Roux gastric bypass described above.  The concept in the single bypass is similar, a narrow reduced gastric pouch that empties again into the small bowel, but in this setting as denoted by the title, only one bowel join-up (anastomosis) is fashioned to empty the gastric pouch.  The benefit of this operation is that it is often deemed to be faster because there is only one join-up and it is, on balance, less likely to create problems with pain and torsion as described above.

The downside of this version of the procedure is that there exists a risk of ulcers at the bowel join-up and reflux of digestive contents such as bowel into the gastric pouch creating significant issues with volume bile reflux which is particularly nasty when the patient is supine such as nighttime sleeping.  Again, we believe that there is a role for both procedures in the gastric bypass setting and as the surgeon, it is my responsibility to explain to the patient which operation I think best suits them and why.

Frequently Asked Questions

• Both are performed laparoscopically
• Both require 1-2 nights in hospital
• Both require post-operative pain relief and antacids
• Both require the same post-operative fluid dietetic changes (as per your dietitian)
• Both should have similar weight loss profiles
• Both can require further surgery into the future