Okay, now, let's review the critical values.
There's a couple things I
want to point out first.
Now you see at the top, it says, "Examples
of a normal white blood cell count."
Now, in the hospitals, you hear us talk about,
you know, 13-38, or 5.8-13.2.
I want you to keep in mind, that's 1,000.
So it's 13,000-38,000.
You saw back on the other sides
how we talked about times 103?
That means you add three 0s.
So just write yourself a note.
When you hear a health care
professional say 13-38, or 5-20,
they really mean 5,000-20,000, or 5,000-10,000.
So when we look at what a low value is,
we'll talk about that they may just say
the number 4, or they may say 4,000.
But leukopenia, that means white
for "leuko" and "penia" means low,
is a white blood cell count that's <4,000.
Now, compare that to the adult.
A normal adult is 5-10 or 5,000-10,000.
So leukopenia, <4,000,
really starts to be a problem
for your patient.
Okay, so you're going to start thinking
if you see a lab value that says,
"White blood cell count <4,"
you know that is too low, because we're <4,000.
That's 1,000 lower than normal for an adult.
Now, the causes could be a viral infection,
or it could be an overwhelming
or bone marrow disorder.
Okay, now, I don't just want to give you
a list. Let's break those down a little bit.
So, why would a patient have a white
blood cell count that's <4,000
when I know that 5,000 is normal?
A viral infection. That can
be one of the causes.
An overwhelming bacterial infection.
Well, does that make sense?
Because if I have a really big infection,
don't I want a whole lot of
white cells to respond?
Yes, you do, but this is an indication
that your patient's body
can't fight back like we need
it to, because it's just
overwhelmed by the intensity
of this bacterial infection.
So if I have someone who
has a really big infection,
and their white cell count is
low, this is a big problem.
The last thing was bone marrow disorders.
So your bone marrow is where
the blood cells come from.
If your bone marrow isn't functioning well,
you may not have enough white blood cells.
Okay, so we talked about leukopenia,
meaning low white cells.
Make sure you underline that "leuko,"
it will remind you that it's white,
and then "penia" means low.
It's 4,000, which is less than normal,
because normal is 5,000-10,000 for an adult.
We know the 3 causes are viral infection,
overwhelming bacterial infection,
and/or bone marrow disorder.
Now, we have to treat these
patients with extra care.
So someone with a white cell
count that this low,
we want to make sure we use special precautions
with them because their immune system
isn't effective. So I would be careful about
who they're exposed to, and
what we expose them to,
because they're going to
be under precautions
to protect that immune system
that's kind of limping along.
So, on this slide, we've organized
it so you have the normal white
blood cell values in the
thousands at the top.
And we're talking here about what
happens when a patient has
low white cell count that's <4. The 3 causes?
Viral infection, overwhelming bacterial
infection, or a bone marrow disorder.
And we want to take extra care with them
to not expose them to any bugs,
that includes visitors who might
have a cold or the flu.
Now, you thought 4,000 was bad, it gets worse.
This is a white cell count <500.
Now that's not 500,000. That's literally <500.
Normal is 5,000, right? That's the
bottom line for an adult.
But this is somebody who has a
white cell count that's <500.
This is the most severe leukopenia,
and this patient is at risk to
die from infection.
That means the kind of bug that most
of us could fight off without any problem
might cause this patient to die.
So white blood cell count <500
when the normal is 5,000, this is the
most severe leukopenia.
At the opposite end of that spectrum, you've
got a white blood cell count that's >30,000.
Remember, normal for an adult is 10,000.
So white blood cell count >30,000 is
leukocytosis, that's extra white cells.
This indicates a massive infection
and an immune system
that is definitely responding.
So, it can either be a massive infection, or
something more serious like leukemia.
Massive infection, we hope we can
address and fix rather quickly.
A serious disease like leukemia
is a lot more complex.
So anytime your numbers are outside of
normal, you need to stop and think,
"Hey, what are all the possible reasons
that this could be happening?"
Look at the rest of your patient
assessment and see what lines up
to help you identify what's going
on with these lab values.