00:00
So I know we have six but let's
start with the most common.
00:03
I want to start with
chronic kidney disease.
00:06
Now your kidneys are meant to
filter things from your blood
put them into the urine so
they can leave your body
but in chronic kidney disease
the kidney itself is damaged.
00:16
So we can't remove
in filter creatinine
and other ways products
like we need it to
to stay healthy.
00:23
So a patient with
chronic kidney disease
will have higher levels
of serum creatinine.
00:30
When we think about
atherosclerosis
you generally think about your
heart, right?
Chest pain.
00:37
But the problem is the same
when the vessels that supply any
organ in your body are compromised
and you're not getting enough
volume of blood to that organ
that organ is going to suffer
if we're talking about
atherosclerosis in your heart
you're going to have
an MI or heart attack
if we're talking
about your kidneys
we call that renal
artery stenosis.
01:00
It just refers to the vessels
that supply the kidneys.
01:03
So when these vessels narrow
and it happens
progressively over time,
it causes a reduction in
the amount of blood flow
that's getting to those kidneys.
01:12
So with the kidneys,
the vessels become
tighter and tighter and tighter
look at the graphic there.
01:18
That's to help you
remember that you can see
blood flow in one vessel is
pretty well free-flowing.
01:24
But in the one that's
got atherosclerosis
or renal arterial sclerosis.
01:28
You can tell that that blood
supply is Significantly diminished.
01:33
See when that happens when you
have reduced renal blood flow.
01:37
It has a huge impact
on the kidneys
less blood flow means those
nephrons become damaged.
01:43
And those are the
ones that help,
how's the units that
filter the blood.
01:48
So we're talking about
acute versus chronic.
01:51
Now, we're talking about chronic
changes that happen in the body.
01:54
Renal artery stenosis happens
over a period of time.
01:58
It's Progressive.
01:59
Chronic renal disease also
happens over a period of time.
02:04
An acute episode is
something that hopefully
if we can resolve
the underlying cause
we can reverse it.
02:10
But chronic has happened
over a period of time
a number of insults to the kidney
and it's much harder to treat.
02:17
Now here's one thing
I want you to remember
when the kidneys
receive low blood flow,
they act like the flow is
because of dehydration.
02:25
So they try to pump
up your heart rate,
try to get that blood
pressure going up higher
which ends up causing more
problems for the kidney.
02:33
So what's meant to be a
compensatory mechanism short term
if your body has experienced
progressive changes
over a longer period of time
it can actually do more
damage to your kidney.
02:44
So you'll notice patients
with chronic kidney disease
generally have hypertension
have to do a lot of medication
treatments to try to bring that down
within a more normal range.
02:54
Now, what about the impact
of RAS and creatinine?
Well, here's something that's really
applicable in the clinical setting
creatinine Rises less
quickly than urea nitrogen.
03:05
So you would expect to
see a rise in your BUN
probably before you would see one
in the creatinine of equal levels.
03:13
So the concentration of creatinine
only becomes abnormal one about half
or more of the nephrons
have stopped functioning.
03:20
Okay, that's really important.
03:22
Please make sure
you write that down
because people can have
chronic kidney disease
and not even be aware of it
and before it gets picked up.
03:30
If they're not getting
regular Health Care,
they may have lost over
half of their nephrons
in their kidneys because of the
progression of chronic renal disease.
03:39
So that's a very important
patient education point.
03:42
That's why physicals on a
regular basis are so important.
03:46
So before we move on from here,
what are the two things
I want you to take away.
03:50
Well creatinine rises
less quickly than BUN
and the second one
the creatinine as
a way to help you
quantify how slow it goes
sometimes over half of the
nephrons have been destroyed
before you'll see that
change in their creatinine.
04:08
Now the GFR is the
glomerular filtration rate
and that's how much blood goes
through your glomeruli each minute.
04:15
Now take a look at our picture
see right there up in the corner.
04:18
You can see the glomeruli is
that little tangle of capillaries
surrounding that is
Bowman's capsule.
04:25
That's a little round
cup that's surrounded it.
04:27
Then you've got, all the tubules
and then it exit
out of the body.
04:32
So when we're talking
about the GFR,
we're talking about how much blood
can pass through that glomeruli
and each minute.
04:40
So what do you think the impact would be
of renal artery stenosis and creatinine?
Well, we've got less
blood going through
and remember that concentration
of creatinine only gets up normal
when a lot of these
units are damaged.
04:55
So they're not functioning
and very well at all.
04:58
So you're going to see that
creatinine rise slowly.
05:01
Okay now we've looked at
chronic kidney disease.
05:04
Let's look at something
a little more acute,
kidney obstruction.
05:09
So anything that
blocks or impedes
the flow of urine can impair
the kidneys ability to function.
05:16
Take a look at that picture.
05:18
So you see we've got
two kidneys there right,
but one of them definitely
does not look like the other.
05:24
Look at that kidneys, it's all swollen up.
And knobbly
that's because that's
called hydronephrosis
that means that the urine is
filling that kidney and
overfilling that kidney,
that's why the
term hydronephrosis
So how does that happen
with the kidney obstruction
will notice that it's only happening
with one kidney in our picture.
05:46
That's because it's
all about the placement
wherever the obstruction is
urine is going to be
blocked upstream from there.
05:53
So in this example,
it's just in one side and one kidney,
but I want you to make
sure you have that term,
Hydronephrosis, right?
You see it there on your slide
and take that graphic with you,
that picture of that gnarly kidney is
because it's all swollen up
because of the obstruction.
06:14
Okay now,
I've got a question for you.
06:17
I want you to think about
what you seen in clinicals,
what are some examples
of things in patients
that could block the
flow of urine like that.
06:25
One is mostly a male condition
and one is only a male condition.
06:31
Right, the enlarged prostate is
definitely only a male condition
kidney stones tend to happen
more often in males too but
females have more
than their share.
06:42
So keep in mind we've talked
about chronic kidney disease
causing high creatinine.
06:46
We talked about
kidney obstruction
anything that blocks the exit
of that creatinine from the body
is also going to give us an
elevation in your serum creatinine.
06:55
Now dehydration.
06:57
BUN in creatinine can both
be elevated in dehydration.
07:01
So see here's what happens.
07:02
She become really
really dehydrated.
07:04
That means your
blood pressure drops.
07:06
Then you don't have good
perfusion to your kidneys
that leads to acute
kidney injury.
07:12
Remember, we've got a chance
to fix the acute kidney injury,
but with the acute kidney injury
comes the elevated creatinine levels
because the kidney can't
function the way it was intended.
07:23
So if I can just
rehydrate this person,
if I can figure out a way to get
fluids back into them appropriately,
we can resolve the acute
kidney injury in most cases.
07:32
So the key is if your
patient is dehydrated
we want to safely re-administer
fluids to get them back to homeostasis
or to fluid volume balance.
07:43
If we can't resolve that acute
kidney injury immediately.
07:47
We might need to
look at pursuing
temporary dialysis
therapy to try to prevent
the damage that can
happen in an AKI event.
07:56
Now let's look at high
levels of dietary protein.
07:58
This one is not so common,
in your practice you
may or may not see this
but dietary protein,
maybe someone who's really
engaged in eating a lot
of meat or protein.
08:11
Why does protein
play such a role?
Remember red meat
is the muscle tissue
of the animal.
08:16
Now it naturally has creatinine.
08:18
So cooking the meat
causes the creatine to
break down into creatinine.
08:23
So when a person eats the meat
their creatinine
levels can go up.
08:27
Now you've got to eat a lot of
meat, okay?
This isn't just one burger
and you're going to see
a shoot up in your creatinine,
but dietary proteins and cooked
meats contain creatinine.
08:41
So there is a diet that is popular with
some people called the carnivore diet
depending on how much
red meat there is
and how well their
kidneys are functioning,
This could be problematic.
08:50
So eating higher than
recommended levels of protein
or comments can elevate
creatinine levels.
08:57
Often times people who are into
bodybuilding without
proper medical assistance
as they're going
through that regimen,
can also end up with
elevated creatinine levels
because they're taking massive
amounts of supplements and protein.
09:11
Now remember cooked red
meats can be problematic.
09:14
But again, you're going to
have to balance that out
and be under a physician's
care and a dietitians
advice and guidance to make sure
you can balance your protein intake
with your body's
ability to process it.
09:26
Now our fifth one
is intense exercise.
09:29
I don't mean walking
from the couch
to the TV or to the kitchen.
09:33
That's not what
we're talking about.
09:34
I'm talking about hardcore long-term
Marathon Ironman kind of thing,
because remember creatinine
is present in your muscles
and helps produce energy.
09:45
We just talked about eating
that creatinine and red meat
but creatinine in
your own muscles
is what helps your
muscles produce energy
to do intense things.
09:54
If you do,
extremely rigorous exercise
that can also increase
your creatinine levels
because your muscle
breakdown is increasing
with that intense activity.
10:03
Now our last one number six.
10:05
There's actually
certain medications.
10:08
Pretty much anything that
can go wrong in your body,
medication can sometimes cause it
as an unintended adverse effect.
10:15
So some of these drugs may increase
your creatinine levels temporarily
without actually
causing kidney damage.
10:21
So make sure when you're
caring for a patient
and their elevated
levels come back.
10:26
You see are they on any of the
medications that you see here.
10:31
Now some of these
are pretty common.
10:32
Look at that in H2 antagonist.
10:34
We take that for stomach acid,
NSAIDs,
people take that
over the counter.
10:39
You can also take it after some really
intense exercise if you're hurting.
10:42
Certain chemotherapy drugs,
cephalosporin or
other antibiotics.
10:47
The point is you can't
memorize this list
because there's just not that
much real estate in your brain,
but I do want you to
have filed the way
for an elevated creatinine level
you want to make sure you thought
through these six categories
and have a basic understanding
of how they impact
your patients lab work.
11:05
So we've looked at those
six possible causes
of a high creatinine.
11:10
I also don't want you to
overlook the possible causes
of acute kidney injury.
11:15
Remember we've grouped
them into three categories
prerenal,
intrarenal and postrenal.
11:22
Prerenal being anything
leading up to the kidneys,
which would include
decreased renal perfusion
and an increased protein
breakdown in the body.
11:30
So we're talking about delivery to
the kidney being a prerenal cause
so if I have decreased renal
perfusion from things like
dehydration, blood loss, shock,
maybe a heart that's not pumping
as well as it should and CHF
that's a prerenal cause
because I'm not delivering
enough blood to the kidneys.
11:49
Now if I have increased
protein breakdown,
what I'm delivering in the body
is overwhelming to the body.
11:57
So increased protein breakdown
comes from something like a GI bleed
because blood has hemoglobin
and hemoglobin is a protein
could also happen
from a crush injury,
from burns,
from corticosteroids.
12:10
So you can have some
extra challenges
with increased protein.
12:14
But the first
category is prerenal
that's talking about what is
being delivered to the kidney.
12:21
Intrarenal is within the
kidney, intra-renal.
12:25
This means I've got something
going on due to nephrotoxicity.
12:29
So you've got
severe hypertension.
12:32
I have glomerulonephritis,
maybe some tubular necrosis.
12:35
Those are really impressive words,
but don't get lost in those.
12:39
Just stop for a minute
and think what we've
got going pre renal
what's being delivered
not enough blood
or way too much
protein in the body.
12:49
Intrarenal something
that's damage the kidney.
12:52
So I've ingested
something that just
killed the tissue,
I have really
severe hypertension
and that was just blowing
through the kidneys
and damage them for some reason
diabetes, glomerulonephritis,
those are all things
that you're familiar with
and interacting
with your patients,
but know that they directly
damage the kidney itself.
13:14
Now last is post renal, right?
That's after we're talking
about some type of obstruction
the most common things you would
see would be something like
you've got a kidney stone
which happen to anybody and
they are excruciatingly.
13:28
Trust me, those people are
not exaggerating their pain.
13:31
It's horrible.
13:32
Or maybe even a male's
problem with the prostate
that's over growing and
causing blockage that way.
13:37
So always be on the lookout
for acute kidney injury
the earlier you catch it
the quicker we can intervene
and do something so
it doesn't turn into
chronic kidney disease.