in Pulmonology, understand the
entire system is being affected.
Let’s take a look at the other two major
shocks here. Once again, what is now causing
decreased oxygenation of your tissue? We either
have cardiogenic or you have obstructive.
Let’s go through each one and the reason
that these are put in the same row is because
many of the features are going to be comparable
and there are certain features that are absolutely
distinct. So, let’s first go through cardiogenic.
Obviously, the causes are going to be different,
right? If it’s cardiogenic,
what happened? Oh,
my goodness! You or the patient has suffered
a myocardial infarction. If there is myocardial
infarction, one of the post MI complications
include your CHF. In acute congestive heart
failure, you would have then a decrease in
cardiac output. You have a decrease in cardiac
output. What then happens to your tissue?
It’s not properly being oxygenated.
Okay, what other issues do we have here? Acute
MI, valvular dysfunction, arrhythmias. You
can notice here that any one of the etiologies
or differentials is all causing your heart
to stop. Okay. So, if your heart stops, then
what do you begin here? It’s not haemorrhaging.
Decreased cardiac output and where does some
of this fluid go? It backs up into
maybe the pulmonary right,
pulmonary edema. If it’s cardiogenic, it
would be transudate, maybe if it’s bad enough,
may result in alveolar haemorrhaging and company.
But, decreased cardiac output. Here once
again, what happens to your stretch? Decreased.
What do you want from your medulla? You want
sympathetic. Okay. So, this is example
number 2 where it’s a shock. We have increase
in your sympathetic and so therefore, I want
you to now move into your diagnosis here and
you would expect to find cold and clammy,
but that’s not specific because it’s
sympathetic. So, let’s go into diagnosis
for each of the shocks here,
Before we move on, I’d just make sure that
we are clear about obstructive and why the
heart might not be properly or the cardiovascular
and the pulmonary system are not properly
functioning as they should. In obstructive,
cardiac tamponade, what happened here?
Maybe the patient had a myocardial infarction.
Maybe there was a scar formation, but
it was weakened, so resulted in a ventricular
aneurysm and maybe there was ventricular wall
rupture. And so therefore, how quickly is
this pericardial cavity being filled up? Way
too quick. What do we have here? Cardiac tamponade.
What is this? Obstructive type. And then we
have pulmonary embolism. Pulmonary embolism
would also be considered
an obstructive type. Let’s talk about the
diagnosis. So, apart from the cold and clammy,
because of why? Sympathetic. Let’s talk
about congestive heart failure. In CHF, well,
what’s that heart sound that you’re going
to create when you have a very large left
ventricle? Take a look at the chest X-ray
and you find your PMI, your point of maximum
impulse to be laterally
displaced, by the midaxillary.
That’s a very large left ventricle and so
now, at this point, as soon as you have diastole
early on, this mitral valve opens and,
blood rushes into left ventricle creating
S3. Where is S3 in relation to S1 and S2?
Good. After S2. So, S2 would be the closure
of the aortic and right after closure, you’re
going to open up your mitral valve
and you’re going to create,
massive flow of blood from left atrium
into left ventricle creating your S3 gallop.
Hopefully, that’s clear.
Next, well, say that your heart’s not functioning
properly. You’re going to back up. Where?
Lungs. One side or two sides? Both sides.
With what? Good. Pulmonary edema. On your
X-ray, you’d find bibasal type of opacity
and upon auscultation, crackles.
It’s a bibasal crackle. Number 1. If
it’s the right side that’s affected, then
you’re going to have, what’s this right
here when your internal jugular vein can be
seen to be pulsating? You should never
normally be able to see the internal jugular
vein, but if you find it to be pulsating,
that's your positive JVP, jugular venous pulse.
Are we clear? Heart issues,
What about obstructive and company? Here
you might have tracheal deviation with obstructive,
especially something like cardiac tamponade
and here, because it’s obstructive,
well, if your pericardial cavity is being
filled up, you cannot properly hear your heart
sounds. And so therefore, it will be muffled.
Okay, now, my problem is this. Now, don’t
memorise this. Work with me.
The heart isn’t working properly and if
it’s congestive heart failure, which is
the best example to give you at this point?
And then you know the heart is filled with
blood, the volume overload. And so therefore,
there’s more blood in your heart, isn’t
it, in CHF? And so therefore, this is then
referred to as being preload. You expect your
pulmonary capillary wedge pressure or your
central venous pressure to be increased and
that’s what you’re seeing here, an increase
in preload. Next, well, here,
if your heart’s not working,
either obstructive or cardiogenic, you can
expect your cardiac output to be, decreased
severely. And, what kind of symptoms are you
finding here? The type of signs, cold
and clammy, right? Sympathetic nervous system,
what is that then doing to your systemic vascular
resistance and arterioles? Good. Vasoconstriction,
increase in TPR. Now, would treatment obviously
be different? If it’s congestive
heart failure and you’re
trying to re-establish your pumping motion,
then obviously you want to use a positive
inotropic agent, maybe something like Dobutamine,
a Beta-1 agonist. And if you want to try to
take care of that edema, now you’re thinking
about? Good. Furosemide, a diuretic.
Whereas if you are dealing with obstruction,
if it’s obstruction that you’re
dealing with, then you’re thinking about
relieving the obstruction. And if you want
to relieve the obstruction and it’s a PE
(pulmonary embolism), you want to blast open that clot and then
if it is something like cardiac tamponade,
what do you want to do? Open up a window ASAP
so that you can drain that fluid and this
is then called Pericardiocentesis.
The last step that we’ll take a look at, as
far as shock where the cardio and the pulmonary