00:00
Now, let's look at the
management of cardiogenic shock.
00:04
Remember, we're still in Layer 3.
00:06
We're prioritizing hypotheses,
generate solutions,
taking action,
and then evaluating them.
00:12
We know the challenge with shock
is to correct the underlying cause.
00:16
And so our management is based
on what the underlying cause is.
00:20
Here are our target goals.
Just as a reminder.
00:22
You want an arterial oxygen
saturation of 92 to 95%,
which may require oxygen support.
00:30
So it might be something
external like a mask,
or the patient may
need to be intubated.
00:35
Our goal here
since it is cardiogenic shock,
we want to improve cardiac output.
00:41
So, we may look
at like vasodilation,
and something to
improve contractility.
00:46
Now, think that through.
00:47
Vasodilation,
how would that help the heart?
Well, it's not going to
have to work as hard, right?
If the vessels are not
as constricted,
after the heart is
pumping out of that
left ventricle, this taken a hit,
that will be easier for the heart.
01:01
Improved contractility means
we're going to help that heart
pump harder more efficiently.
01:07
Does that make sense for
somebody in cardiogenic shock?
Yeah, it makes perfect sense.
01:13
So, vasodilation,
and improving contractility
are two of our goals
in cardiogenic shock.
01:18
Now, the drug of choice,
that's going to vary.
01:21
It depends on the clinical goal
and a thorough understanding of
each drugs mechanism of action.
01:26
We're not going to go
into that detail here.
01:29
But just be aware,
those are the goals.
01:31
Vasodilation,
and improving contractility.
01:34
Keeping in mind, our goal
is to improve cardiac output.
01:37
Let's just look at some
major categories of drugs
and how they do that.
01:41
How do they help us
improve cardiac output?
Nitrates, they take the corner
arteries and they dilate them.
01:48
That's really nice
for the heart, right?
We wanted to get extra
good gentle blood supply.
01:54
Diuretics, reduce preload,
because diuretics cause the patient
to pee out extra volume,
that means there's less volume
in the intravascular space.
02:05
And if we give them appropriately,
that will be less
work for the heart,
because there'll be a reduced
preload coming back to the heart.
02:12
The vasodilators.
They reduce the afterload.
02:16
The pressure,
the heart has to work against
as blood as leaving
that left ventricle.
02:21
And remember, in this case,
we talked about a left ventricle
that had suffered
from dead tissue after an MI.
02:27
Now, beta blockers.
02:30
These guys are [unintelligible],
we use for lots of different things.
02:33
But in cardiogenic shock,
it will decrease the heart rate
and decrease the
contractility of the heart.
02:40
So, if the heart is beating slower,
and not contracting is hard,
it's going to be
less work for the heart
and should end up in
improved cardiac output.
02:50
Now, study tip,
when you're going through.
02:52
Make sure you can look at
these categories of medication
and explain why they improve
cardiac output on your own.
03:00
Not by looking at your notes,
but seeing if you can
retrieve that from yourself.
03:04
Now, if it gets too bad,
the damage or insult to the heart,
a heart transplant
may be necessary.
03:10
Now, I have a question for you.
03:12
Why don't we put the SPO2 sensor
on the forehead of a client?
Normally that goes on the finger.
03:18
Well, this patient is
in cardiogenic shock.
03:20
Meaning where his
blood started to shunt?
Right,
to the heart and to the brain,
Meaning you're not going to get
an accurate reading on the finger.
03:30
That's why we put it on the
forehead when a patient is in shock.
03:33
Remember,
our goals we want to maintain
an Mean Arterial Pressure over 65.
We want to keep that CVP up, right?
We want enough fluid in the body,
but we don't want
to overload the heart.
03:46
Now, keep an eye on
their electrolytes.
03:48
Because we were giving
them a diuretic,
We want to really watch
that potassium closely.
03:52
The loop diuretics,
like furosemide,
can really be problematic
with dropping the potassium.
03:58
Let's take a look
at our shock chart.
04:01
Now, on the left hand side,
you'll see the type of shock.
04:04
We're going to look at cardiogenic.
04:05
So, answer these with me as you go
through to kind of quiz yourself.
04:09
So, cardiac output. Which impact
would you expect up or down?
Well, since we're talking
about cardiogenic shock,
the output is going to be down.
04:19
What about the heart
rate up or down?
That's a compensatory mechanism.
04:25
So, when cardiac output is down,
heart rate is faster,
it's increased.
04:29
CVP. If you see a change,
it will be elevated.
04:33
Now, let me explain why.
04:35
In cardiogenic shock, the client
ends up with fluid overload.
04:39
And that's what results
in an elevated CVP.
04:42
Because remember,
the cardiac pump is not
able to get blood
through the heart.
04:48
So, it's going to back up.
04:50
You might even see
venous jugular distension, right,
because it's backing up
into that venous system.
04:55
So, keep in mind CVP, if you see
a change, it's likely to be up.
05:00
And you may even assess for
jugular vein distension.
05:03
Now, let's finish up
the rest of these.
05:06
PCWP stands for wedge pressure.
05:09
It's also going to be elevated
because of the
fluid volume overload.
05:13
SVR. What do you --
that's kind of an odd one.
05:16
That's the systemic vascular
resistance.
05:18
What do you think? Up or down?
Actually, this is another
compensatory mechanism.
05:24
Because that cardiac output is down.
05:27
The body's going to try to
constrict those vessels.
05:29
So, your SVR which is a
measurement of that will be up.
05:33
O2 sat? Yeah, that's a no
brainer in shock, isn't it?
It's going to be down in this one
in cardiogenic shock.
05:40
Your output is down,
your heart rate is up.
05:43
That's another sign
that that oxygen sat
is not where we want
it to be 92 to 95%.
05:49
So that's it. You finished our
series on cardiogenic shock.
05:53
Join us for the others.