[Music]
the other item that we need to think
about with both compliance and surface
tension is how this affects the overall
work of breathing so this is how much
energy it takes for a person to breathe
to do this we have to know that the
lungs themselves want to collapse so to
actually breathe you're going to have to
overcome the elastic force necessary for
there to be a collapsing of the lungs we
can use a diagram such as this in which
we have the amount of pressure on the
x-axis and volume on the Y we're going
to have a number of different
denotations on this graph just to help
you orient of what part we're talking
about so if you're trying to overcome
elastic forces that is the force between
a b c d and 0 then back to a so that's
all of that portion that is shaded in
that kind of a grey blue to overcome the
non elastic forces that is this
particular graph where we go from a e C
F a so it forms that kind of nice
elliptical circle there the inhalation
component goes from a II C B a or that
part that's just on the right hand side
or during exhalation it's a B C F a why
this becomes important if someone has a
restrictive lung disorder it's harder
for them to fully inflate their lungs
because of resistance in inflation
therefore that person isn't going to
need to generate a greater negative
pressure to fully fill the lungs so they
are going to take more energy to fill
the lungs therefore when they go from a
II see F a it requires a greater
pressure change and therefore they have
to exert a lot more effort to get out
that or get in that particular air
obstructive disorders also have a
problem with worker breathing but you
notice for this it really just inflates
this particular graph because they have
a problem getting a lot of their air out
and so they're overcoming a lot of
resistance so they have to push air out
of the lungs and that can be seen in
this route diagram where we have a e C D
F back to zero and then a where work of
breathing comes in together with the
rate of breathing is that we are trying
to overcome both non elastic and elastic
work and this creates a total work
component most people's respiratory rate
is at the area of the lowest amount of
total work can be seen here in a
pathophysiological state such as someone
that has a restrictive lung disorder it
creates a lot of work for them so if
it's hard to inflate your lungs taking a
lot of effort to do so how do you avoid
doing that maybe you just breathe more
frequently so someone with a restrictive
lung disorder oftentimes has a very high
respiratory rate simply because they're
trying not to work as hard
- totally inflate their lungs
[Music]