Digestive Process After a Bypass Surgery


Q: Hello, My friend is willing to have a gastric bypass surgery (Roux en-Y), so we are trying to understand some relevant details about it, for her to feel the most comfortable with the decision, and for reducing to the minimum the surprises after surgery is already done. Some questions we couldn't find answers to are regarding the digestive process after the Roux en-Y gastric bypass surgery - both proximal and distal. We'll be thankful for any answer - 1. Does the pouch left from the stomach secret gastric juice like a normal stomach? 2. Does the old stomach secret gastric juice? And does the juice come in touch with the food and digest it? If so, at what stage? 3. Are duodenum digestive enzymes and or juices secreted after Roux en-Y Surgery? And do they come in touch with the food and digest it like before the surgery? - If not, how is the acidic chyme being buffered? Are intestinal ulcers a potential problem? 4. What is the physical or biochemical or any reason for the nausea and abdominal aches after ingesting fatty and or sugary foods? Does this happen both in the proximal and distal Roux en-Y? 5. Why is it that many times the gall bladder is starting to ache some time after the surgery? and again, in which version of the surgery is it? 6. A bit out of subject - from what material would be the implanted new connection tubes? I apologize for the high number of questions, and hope you can answer us at least to some, or perhaps direct us to someone who could. Thank you very much!


A:   It is quite understandable that you friend would have concerns about undergoing a procedure of this nature. Let us look at each question separately:

Yes. Any remaining portion of the stomach will secret substances normally. Since there is a smaller portion, less gastric juice is produced.

All portions of the stomach that remain after the procedure will produce gastric fluid.

Themajority of the stomach will be bypassed. However, within the small portion of the stomach that food does enter the digestion process will continue as it would in a normal stomach.

The duodenum continues to secret all its substances but it is completely bypassed during surgery. Therefore, after surgery, no food enters the duodenum. This is a desired effect as it reduces absorption of ingested food and thus aids weight loss. The acidic chyme is buffered by the secretion of the pancreatic juices, which is major buffering agent in the normal digestive process.

Intestinal ulcers are not a recognized complication of gastric bypass surgery. A marginal ulcer may develop. This ulcer develops at the connection made between the stomach and the small intestines and requires the same treatment as stomach ulcers.

There are several complications that can explain the symptoms you describe regardless of the type of procedure. These include the development of gallstones, distention of the distal stomach and narrowing of the artificial passage between the stomach and the intestines created during surgery. Due to massive reduction in stomach size, not adhering to the strict post surgery diet may result in forceful distention of the stomach and this too can result in abdominal pain and nausea.

This is most likely due to the development of gallstones that can potentially occur after Roux-en-Y bypass. This can happen in both proximal and distal Roux-en-Y procedures.

There are no artificial connection tubes used. The small intestines are used as the conduits to "direct" food into the "new" stomach and throughout the rest of the digestive tract.
I hope all your questions have been sufficiently answered.

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