The most effective procedure for weight loss and resolution of diseases such diabetes, hypertension and obstructive sleep apnea is the laparoscopic gastric bypass procedure.  So if you are a patient pressed about what procedure to do, i.e. sleeve vs bypass, then knowing what the risks are may help you confirm your decision. It is my hope that this short article will shed some light on this question that I often get in my clinic. Which operation is best for me?
To answer this question I take into consideration several factors.  First, is most important, patient preference. I believe that the more a patient is informed about the risks, benefits, alternatives and risk to the alternatives to the treatment of obesity the better the outcome one will have.  So if a patient tells me that they have researched and understand how the bypass procedure works and they have witnessed great outcomes in others, in other words, a good working support group is all ready set in, then I confirm their clear understanding of the risks.  The gastric bypass procedure allows a patient to lose weight and resolve disease via multiple mechanisms.  The most clear mechanism is the creation of the stomach pouch.  This tiny stomach pouch intuitively makes one think that smaller stomach means smaller meals, but it is actually in the connection, called the gastrojejunostomy, or anastamosis, size between this new stomach and the rerouted small intestine that the functional restriction of meals occurs. Once the stomach pouch is created, the gastric bypass restores continuity of the digestive tract by rerouting the proximal small intestine with a 19-21 mm circular stapler.  This connection if you can imagine is about the size of a dime.  This restriction in flow is a tremendous benefit for losing weight.  It is not surprising that the most common risk associated with the gastric bypass is with this connection.  In less than 12% of cases an anastamotic stenosis or narrowing of this connection can occur abruptly obstructing flow to food and even water.  Fortunately, this narrowing can be remedied with an upper endoscopy and single balloon dilatation, and rarely is a repeated surgery needed.
The technology and minimally invasive techniques continue to significantly improve making the gastric bypass safer and safer.  Where the lap band has double the risk and more reoperations than any other weight loss procedure, surgeons and patients prefer the bypass because not only is it lower risk and safe procedure, but the durability is extremely high! It really is hard to hurt yourself with a bypass.  Additionally, the gastric bypass was made to be reversible.  Although, reversing the procedure is rarely needed, patients feel comfortable knowing this fact.