Last point here brings us to rapid squatting.
Couple of things that you want to keep in
mind with rapid squatting. Well here is a
maneuver that you as a clinician are perfoming
or asking the patient to do to figure out
as to what kind of murmur your patient might
be suffering from. Or a maneuver that a child
would be conducting to relieve a particular
symptom that the patient might be feeling.
So what are we getting at here? With rapid squatting or
squatting in general, what you want to
do is you want to be able to delineate the
two conditions in which squatting becomes
beneficial for a clinician, in which you want
to see us as to whether or not the intensity
of the murmur is going to increase or decrease
and you ask the patient to conduct rapid squatting,
then blood will be returned to the heart in
an increased fashion. Is that clear? Now what
about this patient? Ready? It is a child, he'd
love to play. "Mummy I want to go play."
Play hide and seek and while at some point
when the child is seeking that hiding place,
the child gets tired and the child squats,
but not to increase venous return. The child
is instinctively squatting because the child
feels tired. The child has hypoxemia. The
child is experiencing cyanosis. The child
might have pulmonic stenosis, right ventricular
hypertrophy, ventricular septal defect. Those
three will give you the clinical picture of
your patient and what is that picture that
I am referring to? Why those three? Pulmonic stenosis always
begin there. Right ventricular hypertrophy
and ventricular septal defect result in what
kind of shunt in that case please? It is one
of the most common congenital cyanotic heart
disease and it is called tetralogy of Fallot.
"But Dr. Raj you only gave me three, I thought
tetra means four. Why being so foolish Dr.
Raj?" Because I am giving you the three in
which it gives you the clinical picture. What are
those again? Number 1, pulmonic stenosis. Number 2, right
ventricular hypertrophy. Number 3 was ventricular
septal defect resulting in a right to left
shunt, interesting. VSD in that case would
be right to left because of the other predisposing
issues. The fourth and final tetra would be
the overriding aorta. Now why am I bringing
this up? Because that squatting maneuver that
the child was performing instinctively was
then causing increased in TPR. Our discusison
earlier with TPR was what? When you increase
your TPR, what does it do to your afterload? Good.
It increase afterload. If you increase that afterload,
then what are you doing with the left ventricle?
You're increasing the resistance to the left ventricle
is facing. So now at this point, with that
child feeling cyanotic, with the squatting
maneuver is then going to reverse that right
to left shunt to a left to right shunt. And
by doing so, relieve some of the cyanosis.
Is that clear? So we have squatting in two
different conditions. What we have here is
the fact that it increases venous return upon
rapid squatting, so that will be to the right
side of the heart through your veins. And then
tetralogy of Fallot, that squatting
would be conducted or performed to relieve
the symptoms of your patient.