Okay, so, first, let's start
with the white blood cells.
We're going to look at some general
information and the role of the cell.
You already know that the white
cells fight infection, right?
But it's when attacking bacteria,
viruses, and germs invade your body,
these are the cells that respond.
They live about 13-20 days, so just
short of 2 -- about 2-3 weeks,
and they're destroyed in the
Okay. So the white cells, they're the ones
that respond when our body is attacked,
and they live about 13-20 days, and
they're destroyed in the lymphatic system.
Now, the red blood cells -- remember,
they're the ones that carry the protein
hemoglobin, that's what binds to oxygen.
So, the job of the red blood cells
is to carry oxygen to the tissues
and CO2 to the lungs to be exhaled.
So they're just transporters.
That's what's floating around in your
bloodstream that goes to your lungs,
picks up the oxygen, dumps off the CO2,
delivers oxygen to your tissues, picks
up the CO2, brings it back to the lungs.
Repeat, repeat, repeat, right?
Now, they are made in the bone marrow
and they last about 120 days.
Okay, anytime you get this much
information in something,
look at the things that are the
same or are different.
White blood cells -- make yourself
a note -- they fight off attack.
Red blood cells carry oxygen.
White blood cells live 13-20 days.
Red blood cells live 120 days.
Now, platelets are about 20% of the
diameter of a red blood cell.
That is amazing to me and
they are super tiny.
Their principal function is to
Okay, so the job of a platelet is to
clump together to make a clot,
and to kind of put a plug in the hole
where your body is leaking blood.
They live about 8-9 days.
So let's look at lifespan.
Who has the shortest lifespan?
Right. Platelets, 8-9 days.
Who has the longest lifespan?
Right, red blood cells.
And then we've got the white
blood cells in between.
So you might make yourself a quick
note. Number them 1, 2, and 3
as far who has the shortest to
the longest in your notes
to help you remember that
point before we move on.
Okay, now, what color tube
should we use for a CBC?
Now, you may be in an area where you're
responsible for drawing the lab work,
or you may have a phlebotomist come
from lab and draw the lab work for you.
But these are all the options that
you can use to draw blood.
Okay, so what's your guess? Maybe, you know.
Maybe you're just going to pick a color,
but pick one before we move on.
Okay, did you get it?
Right. It's the purple top tube.
So that's the color tube we
should use for a CBC.
The reason these tubes all have different
colors is that they have different additives
and things in them that help
the lab perform the test.
So it's really important that you put the
blood sample in the correct color tube.
Now, I always get asked, "Can you draw
blood above an IV site for a lab test?"
Well, it's a great question, but "no" is the
best answer if it can be avoided.
Don't use an arm with an IV if you
can possibly avoid doing that,
because the IV may affect the lab
results depending on
what's in the IV, how much fluid, etc.
So if you're asking if you can draw
blood above an IV site,
try not to if you can avoid it.
Try using an arm that doesn't have an IV.
But if you don't have any other choice, then
try and draw it from below the IV site.
So, if your IV is up here in the antecubital,
try and draw your blood
from below that site.