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Hey there friend, I’m Christina Rafano from and in this video we are going to talk about cretinine clearance. Yeah, I know you’re confused by it, because
I was too in nursing school. So let’s break it down. And be sure to stick around until the end
of the video because I’ve got a free lab value cheat sheet to help you out with lab values
in nursing school. Alrighty, so creatine is just a big fancy
word for trash. Okay, it’s not exactly trash, but it is trash. It’s just a waste product that your muscles
make when they work hard all day. So as you move around, and go throughout your
day, your muscle cells are constantly building up and breaking down in order to stay healthy. And when muscle breaks down, it releases creatinine. So creatinine is just a waste product of muscle
metabolism. That’s all it is! Now here’s where things get interesting. The kidneys are fully responsible for getting
rid of all of this creatinine. So they’re job is to take it all out of the
blood and excrete it into the urine. So, let’s walk through some critical thinking. What do you think will happen to the creatinine
level if the kidneys are damaged? Will they be able to get out as much creatinine
from the blood as they were before? No sir! If they are damaged, the kidneys can’t do
their job as well to get rid of all that creatinine, so the creatinine level will build up inside
the blood. Now, this is why we measure creatinine clearance,
it’s primarily to check for kidney function. So creatinine clearance is mostly a test of
the kidneys, it tests the glomerular filtration rate, meaning, how long does it take for the
kidneys to get rid of all that creatinine? So creatinine clearance is a really good test
for kidney function. It shows us how well the kidneys are doing. Alright, so typically how we test for this
is a 24 hour creatinine clearance test. So over the course of 24 hours, you’ll collect
the patient’s urine. Now here’s a KEY POINT, you’ve gotta know
this for nursing school, it’s almost guaranteed to show up on one of your exams somewhere:
when you do a 24 hour urine collection, you MUST have the patient void FIRST before you
start, and then 24 hours later, you need to collect that last urine right at the 24 hour
mark. So, when you go to start the creatinine clearance
test for a patient, are you going to walk into their room and collect their urine right
then. No! You’re not, because the 24 hour clock hasn’t
started yet. You will need to have them use the bathroom
FIRST, and then that starts the 24 hours and you’ll collect all of their urine for 24 hours. You’re just trying to get it as precise as
possible within that 24 hour time frame, and if you collect urine that they made BEFORE
the 24 hours started, the results would be off. So that’s why this is super important! Typical creatinine clearance is between 90
and 120 mL per minute, roughly. Of course, it varies for men and women, and
it may also decrease with age. And there are some things that increase and
decrease the creatine clearance value. So let’s walk through some critical thinking
with these ones as well. Creatinine clearance may increase if someone
eats a whole lot of meat and protein, or does a lot of weight lifting, because that’s building
up muscle and the creatine levels inside the blood, so obviously, creatinine will be higher,
and therefore the creatinine clearance will be higher. Now a decreased creatinine clearance would
happen in kidney disease or kidney impairment. Because like we said before, if the kidneys
are damaged, they can’t do their job. And because their job is to get RID of creatinine,
if they’re damaged, they can’t do that. So that creatinine clearance value would decrease. The same goes for dehydration, where the kidney
just isn’t getting enough blood flow or there’s just not enough fluid to pass through into
the urine, then you might see the creatinine clearance be a little lower as well. So basically, if the kidney might possibly
be impaired in any way, most likely, you’ll see a decrease in creatinine clearance. And that is creatinine clearance. Now I put a link in the description below
this video so you can download your free cheat sheet. Be sure to check out the other videos we have
for you to help you out with lab values and med-surg nursing. And as always, hit that like button, share
this video with your friends who might also need some help with creatinine clearance,
and don’t forget to subscribe and hit the bell so you never miss a video. Thank you so much for watching friend. Now go become the nurse that God created only
YOU to be. I’ll catch you right back here next time,
on the nursing school show. Take care.

About Bill McCormick

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  1. Thanks for watching!! 😃 Be sure to download your FREE cheat sheet right here > >

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