Question about GI obtruction and kidney function.

flexpap · Joined: 08 Mar 2010 Posts: 1 Location: atlanta

I am radiography student

I read in my book that an obstruction of the GI can only be observed if a patient take oral contrast with a CT of the abdomen.

Yet, I have this CT techs telling me that an obstruction can be seen with just a plain abdominal CT without oral contrast. How is that possible? Don't you need the oral contrast to highlight the GI tract to demonstrate the obstruction?

My other question is about the kidneys. If the BUN and Creatinine levels are not correct (kidney functioning incorrectly) i understand you cannot give iodine thru IV for a CT scan but you can give it orally. Why?

Would'nt the iodine eventually reach the blood stream and then to the "incorrectly functioning" kidneys and cause a problem?

CATbird · Joined: 04 Nov 2010 Posts: 1

Can you see an obs w/o oral contrast? Yes. Is it more difficult to determine the transition point? Yes. Oral contrast is always a good option but lots of docs don't want to wait for it.

#2 Not all oral contrast contains iodine. Most do not contain it in significant amounts. Barium sulfate contains none. IV contrast dumps it to the kidneys all at once which puts them under extreme load and with an already underfunctioning system can cause more damage or complete renal failure.