Step I FENa question

Started by tomtom1287
Get help with your application

Use all the free resources available to you from SDN: articles, guides, expert advising, forums discussions, and school research.

Browse articles Compare schools My application plan Read Interview Feedback
Practice for interviews Ask an Advisor
T

tomtom1287

Full Member
7+ Year Member
Screenshot (9).png
Hey guys,
This is a question from kaplan qbank.
can some one please explain why fractional excretion of filtered na is increased in this situation with reduced gfr where there is no increase in urine Na excretion? Wouldn't urine na excretion increase when there is an increase in FENa?

Thanks for the help
 
Last edited:
Sort by date Sort by votes
Where does it say no increase of urine Na? I saw no mention of urine Na... only FENa.

Renal insufficiency you can almost always assume elevated FENa which is a marker for renal problems. Reduced GFR further backs the point.
 
Upvote 0 Downvote
His GFR is down and so he also has lower urine output so he may not be excreting more Na+ overall, however he likely has ATN so we can clearly say the proportion of filtered Na being excreted (FENa) is increased. Hopefully that makes sense.


Sent from my iPhone using SDN mobile
 
Upvote 0 Downvote
"For ease of recall, one can just remember the fractional excretion of sodium is the clearance of sodium divided by the glomerular filtration rate (i.e. the "fraction" excreted)."- WIKI

DECREASE GFR....INCREASE Fe NA
 
Upvote 0 Downvote
GODinyou99er said:
"For ease of recall, one can just remember the fractional excretion of sodium is the clearance of sodium divided by the glomerular filtration rate (i.e. the "fraction" excreted)."- WIKI

DECREASE GFR....INCREASE Fe NA
Click to expand...

In Pre renal failure, there is decreased GFR but decreased FENa as well. I'm a bit confused
 
Upvote 0 Downvote
You must log in or register to reply here.