I want to dig a little deeper in this blood
pressure management because we
teach patients all the time that
normal blood pressure is
< 120/80 mm Hg, right, since we changed
the numbers a little bit.
But blood pressure management
in acute ischemic stroke
is different than acute hemorrhagic stroke.
Okay. So, pretty much the takeaway point,
blood pressure management
post stroke is different.
Just right there. You've got that. And
then you can break that down,
it's even different between an
ischemic stroke and an acute
hemorrhagic stroke. So, we're talking
about the acute phase of stroke
because there's also differences in the
management of blood pressure in the acute
and chronic phases of both strokes. Okay.
So, if I don't have you confused enough,
let me explain it a little better.
See, Mr. Johnson's blood
pressure, let's use that as an
example. Mr. Johnson had
an ischemic stroke and he got alteplase,
which is a thrombolytic drug.
A clot -- boom -- it's a clot buster. So,
for the first 24 hours after his thrombolytic
alteplase, the Critical Care nurse is
going to monitor and maintain
his blood pressure at or below,
180/105 mm Hg. Okay, so
if it gets above that, here's an
example of 3 medications that
might be used: labetalol,
nicardipine, and clevidipine.
So, those are 3 medications that
might be used. Remember,
Mr. Johnson's health care provider
is going to order specific
medications for the nurse to use, but we
wanted to give you 3 examples that might
be used or considered. So those
are the 3 medications just
that are examples of that. Now,
if Mr. Johnson had not
received alteplase, right, his
hypertension wouldn't have been
treated, unless it was extreme. So,
if he had not received alteplase,
we really would let his blood pressure,
it'd have to be > 220/120 mm Hg
before we would treat it. Now,
remember for Mr. Johnson,
we're keeping it below 180/105 mm
Hg because he had the alteplase.
If he hadn't had the alteplase, we wouldn't
treat it unless it was > 220/120 mm Hg.
And those represent systolic blood pressure,
SBP, or diastolic blood pressure, DBP.
So, unless Mr. Johnson had some other
comorbidities -- why, I keep giving you these
caveats, don't I? Right. Normally, that
would be our measurement, not
> 220 mm Hg or 120 mm Hg if he
had not received alteplase.
But if Mr. Johnson had some other
comorbidities, like he was also having
ischemic heart disease, or he was in
heart failure, or we're worried about
his aorta dissecting, meaning that it
was splitting apart and leaking,
we would run a lower BP. But you
wouldn't be the one who decided that.
The health care provider would write
very specific orders on the safe
range of blood pressure. We're just giving
you kind of an idea of where health
providers would write those orders
or what they would be
thinking about when they set the
ranges. Okay. Let's review.
You're going to see how smart you feel.
Why is a higher blood pressure allowed for
patients with ischemic stroke
who do not receive alteplase?
Okay. Here's the answer. In ischemic
stroke, the perfusion pressure
after the obstructed vessels is low,
and the vessels are dilated.
Okay. That's a lot of words. Let's break it
down. So, if I've had an ischemic stroke
which some days, the way my
mouth works, I think I have, but
if I've had an ischemic stroke, the
perfusion pressure after the obstructed
vessel is low. So let's say the clot was
right here, okay? So, this is blocked
off right here. So the pressure
after the blockage is low,
and the vessels are dilated. Okay. So,
my brain wouldn't be able to effectively
auto-regulate these dilated vessels.
So those vessels that are
dilated are dependent on my systemic
blood pressure for perfusion.
Okay. I don't want to speak through this
point because I want you to feel comfortable
why we allow a higher blood pressure.
So, I got a clot here. So what are
the vessels like after the clot?
Right. They're dilated which drops pressure,
and so the perfusion pressure after
the blockage is usually low.
The brain can effectively auto regulate
that. The brain says, "Hey, I know
you're not getting enough perfusion here,
but there's nothing I can do about it."
So the only way we can have
this brain well-perfused is if the
total systemic blood pressure
is higher. That's why
we allow a higher blood pressure
after an ischemic stroke.
Now, how is blood pressure treated
in a hemorrhagic stroke? We got
the ischemic stroke part, but what
about a hemorrhagic stroke?
And when we say hemorrhagic stroke,
that means you're bleeding
in your head, okay? So that's why
we're going to treat that differently.
So, for blood pressure management in
acute bleeding or hemorrhagic stroke,
the patient's blood pressure is often already
elevated. And so, an acute stroke,
like 150-220 mm Hg systolic, if that's
what the patient is running,
where they've got a systolic pressure running
between 150 mm Hg and 220 mm Hg,
our goal and our target is to lower
that systolic pressure to < 140 mm Hg,
We found out there's really no clear benefit
to getting it lower than 140 mm Hg
in the first few hours of the
acute phase. So our goal
is to get it just like right to 140 mm Hg.
We're not going to
push them all the way down to 120 mm
Hg because it really doesn't do that
much benefit for the patient. So,
we're talking about an acute
hemorrhagic stroke, right? Usually,
the blood pressure we see like
150 mm Hg to 220 mm Hg. We just want them
a little bit below 140 mm Hg and we'll
be really happy. Now, if I have an acute
stroke with a blood pressure > 220 mm Hg,
we're going to get real aggressive.
It's game on like Donkey Kong, so
we are going to get super aggressive
with that blood pressure.
Now we're not giving oral meds,
we're giving an IV
infusion of antihypertensives. And we're
monitoring that blood pressure every
5 minutes. Because you can imagine,
we've got a problem. If you have
a bleed in your head and your
blood pressure is super high,
you're just a fountain squirting inside
your skull and nobody needs that.
So, if you're that high, if you're > 220 mm Hg,
we're going to give you IV infusion and
be checking your blood pressure
every 5 minutes trying to get your
systolic blood pressure down
to 140/60 mm Hg. Okay, so before we go on,
I want you to make sure that you know those
key numbers to give you a frame of
reference of a general idea of how
we treat blood pressure management.
Now stop and think how is this
different than an ischemic stroke?
Compare the 2 sets of numbers
so you have a good feel.
Make sure, before we go on, that you
pause the video and think through,
hat kind of blood pressure would I
maintain if I had someone who had an
ischemic stroke? What kind of blood pressure
would I want to maintain if someone
had a hemorrhagic stroke?
What's the rationale
why I have a lower blood
pressure in ischemic stroke?
How does someone with an ischemic
stroke rely on systemic blood pressure?
Why do they need to?
Okay. Those are just some pause and
recall questions. Let's keep going.