Hello, welcome to our video
series on electrocardiograms.
In this one, it's going to get really serious.
We're talking about ventricular fibrillation.
Now, here is an ECG in normal sinus rhythm.
We'll show you this in every part of our series.
We chose to start with this strip to remind you, this
is what a completely normal strip would look like.
Now we're back with our patients.
This time, we're going to
check on this particular lady.
After previous discussions, at first glance, we
know something is very wrong with this ECG.
Are you feeling intrigued?
Do you want to know why this ECG looks like that?
Good? Let's find out together.
V fib is a cardiac dysrhythmia where there
are abnormal electrical impulses in the ventricle.
Ventricle fibrillation is are caused by
multiple weak ectopic sites in the ventricles.
These ectopic sites fire chaotic electrical
signals that cause the ventricles to quiver,
or fibrillate, rather than contract.
Now due to this contraction inefficiency,
the heart pumps little to no blood,
which can quickly lead to cardiac arrest.
Now here is a reminder of the seven
steps we use to analyze any strip.
We're not going to go into detail here,
but we have introductory videos that do,
but you're going to pretty quickly see how
we can answer most of these seven questions
on a ventricular fibrillation strip.
Let me explain what I mean.
Step one, we're looking at
the heart rate and rhythm.
So first, in order to determine what rate
this is, we would count the QRS complexes
on a 6-second strip and multiply it by 10.
Yeah, not happening here, right?
This is not possible in V fib.
Now if we're going to look at the
rhythm, that is also not possible,
because we don't see regular QRSs so
we can't identify that the rhythm is regular.
And here's a tip, It's
not in ventricle fibrillation,
Analyze the P waves, I think you already
know where we're going on this one.
You can't because there aren't visible
P waves on a ventricular fibrillation strip,
what's going on is that
ventricle is just quivering.
So no way to analyze the P waves
because there are no visible P waves.
So if we tried to compare this strip, like we
have all the others to normal sinus rhythm,
you'll see that in the normal sinus rhythm, you
have a normal P wave, which means there's a
organized atrial contraction, and it
happens before every QRS complex,
which is the result of the ventricle.
ventricular fibrillation? that isn't
happening, so we don't have P waves.
Next, the rhythm is regular in normal sinus
rhythm and sometimes it can vary with respirations
but the ventricular rhythm in
ventricular fibrillation is not regular,
and the heart is not pumping blood.
Now remember this, that's
what your ventricles are doing.
Now, I use weird noises
and silly facial expressions
because anything I can do to help you remember
this content, I am ready and willing to do it.
So when you think of ventricular fibrillation,
know that that is just not an effective
way to pump blood, whether it's
atrial fib, or ventricular fibrillation,
but with this particular rhythm,
this could quickly lead to death.
That's why this rhythm is a much
bigger emergency than atrial fibrillation.
Normal sinus rhythm, the
rate ranges between 60 to 100.
the ventricles are quivering.
So using our study tips, you've got six boxes here.
Remember, a good way to help make
sure you get that information into your brain
is cover those six boxes, and then
try and answer the questions on the left
without looking at your
notes, and then check yourself.
I promise you, that is one of the best ways
to get information out of your working memory,
where you feel like you got it
and into your long term memory,
where you really will have it
when you need it on an exam.
Now measuring the PR interval, I
know you've already got this by now but
obviously if we don't have a P
wave, we can't measure a PR interval.
So that's out, so so far, could we do step 1?
step 2? No.
All right, we're over 3 right now.
Let's look at 4.
Ah, we've got another winner.
You can't measure the QRS, we
have no discernible QRS complexes.
So we can't do number 5, you can't examine
the ST segment and you can't do number 6, either.
Wow, so far 1,2,3,4,5,6 - we can't perform
because we don't have discernible waves.
I bet you can guess a number
7, if we can, or we can not.
That's right, you can't measure it.
That squiggly line, we
can't get much data off of it.
So you cannot measure the ventricular wave because
the ventricles are fibrillating or quivering,
can't measure the QRS because the
ventricles are fibrillating or quivering.
See, so when we review why
this is ventricular fibrillation,
it's not measurable because
there's no QRS as far as heart rate.
We can't identify a regular
rhythm because it's fibrillating.
The P wave isn't there.
We also don't have a QRS, so we can't do
the PR, and none of these are appropriate.
So how do you identify ventricular fibrillation?
Well, we used to tell, if we got a unit
Secretary come on the unit who is not trained
in how to interpret ECGs, We used to
tell them, if the monitor goes like this,
or like this, come get us really fast.
So this is actually a rhythm that
you should be easily recognizable.
It has none of the parts of the normal sinus rhythm
that you are have already learned to identify.
And you're just going to have a
squiggly line across the screen.
Thank you for watching
this part of our video series.