00:01
Hi, welcome to our video
series on electrocardiogram.
00:05
On this one, we're going to talk
about the treatment for asystole.
00:09
Now look at the normal sinus
rhythm compared to asystole.
00:14
This one is really obvious that
they are completely different,
but let's review the obvious,
why this strip is asystole.
00:24
Now the heart rate cannot be
measured because there's no QRSs.
00:29
Why are there no QRS complex?
Because in asystole,
there is no electrical activity.
00:36
That's why we can't look at the rhythm
because there's no electrical activity.
00:41
P waves, we can't see them
because there's no electrical activity.
00:47
PR interval, we don't have any P
waves, So we can't measure the PR
because there's no electrical activity.
00:55
QRSs, again, no electrical activity.
01:00
Now you might be kind of annoyed like why
did you have to say that multiple different times?
What's going to make sense when we talk about
why we don't defibrillator patients in asystole.
01:11
So here's what we can do with asystole.
01:15
CPR.
01:16
So we can do cardiopulmonary resuscitation.
01:20
If we can get advanced care to the patient,
epinephrine can be given every 3 to 5 minutes
during the code.
01:27
And then we do rhythm checks
after 2 minutes or 5 cycles of CPR.
01:33
So anyone who's CPR trained in
the community could perform CPR.
01:37
You would need someone who's specially trained
to give the epinephrine every 3 to 5 minutes.
01:44
They would also have a monitor where we
could check the rhythm every two minutes.
01:49
So let's get back to our question.
01:51
Why don't we use defibrillation with asystole?
Well, we've got a little reminder up
there in the graphic of what defibrillation is.
01:59
You see the two pads, those squares on the patient.
02:02
They have wires coming to
them, those lead to a defibrillator.
02:06
Now the artist has put those
yellow lines in there to remind us that
that's where the electrical
shock will travel through the heart.
02:13
The purpose of defibrillation
is to kind of reset the heart,
and you need to have a certain level
of, let's call it electrical activity available
in order for that to happen.
02:25
Now, let's talk in some
little more science-y terms.
02:28
But the key takeaway point is
defibrillation is not effective for asystole.
02:34
We can use it for pulseless V Tach, or
V fib, but we do not use it for asystole.
02:43
Now let's talk a little bit more about
why it's not effective for asystole.
02:49
Because the problem here, remember
how many times we went back and said,
there's no electrical activity?
Well, in asystole, there is no electrical
activity to be reset in the cardiac myocytes.
03:03
In a normal functioning heart, the myocytes are how
the natural pacemaker function of the heart is used,
and you have a coordinated contraction of
atrium and ventricles, and atrium and ventricles
when everything is coordinated
and flowing smoothly.
03:20
Now, in order for that to happen, you
have to have a controlled flow of ions
and they go in and out of the cells,
In ventricular fibrillation and ventricular
tachycardia, there's an uncoordinated flow of ions,
but they're still flowing.
03:36
So the cells are depolarizing, left and
right and that's why they are fibrillating
but remember, there's electrical activity there
in V fib and V Tach, it's just not coordinated.
03:48
So you have atrium and ventricle are
not working like they're supposed to.
03:52
You've got either, or you've got
So that's the difference.
03:58
Defibrillating always tries to
reset the ion flow in depolarization
but it only works if there's already
potential energy stored in those ion gradients.
04:09
With asystole, there is no
potential energy in the myocytes,
no ion gradients for the muscle cells to release
all at once and that's how defibrillation works.
04:21
No electrical activity in
asystole - no point in defibrillation.
04:27
Thanks for watching our video series today.