I think you need to see your GI and if you don't have one get referred to a good one.
I've had barium CTscans ordered by GI but don't know if that is the test your surgeon is talking about. I drink lots of barium, make sure to take a straw in case they don't have one, and they put something in through an IV that makes me feel warm before passing me into a CTscan machine. Takes less than a minute. Drinking the stuff takes longer. They were looking to see if anything about my small intestines was wrong - were they inflamed etc.
In another test I drank some barium, they took an X-Ray every 20 minutes as the barium worked it's way through my intestines through to my pouch. In this one they were looking for strictures, twists, kincks etc, that could cause obstructions or partial ones. This test isn't as precise as the test above.
I also had a plain endoscopy performed by my GI. I have a hiatal hernia too and nothing is done for it either as it is so small. My GI had to dilate the bottom of my esophagus as I had a swallowing problem. I have also been on medication for heartburn for years as I have GERD.
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