Hello ladies and gentlemen.
In this lecture we're going
to discuss some Special Areas of Anesthesia
in which the anesthesiologists must adapt
to Complex Surgery or Complex
Medical Conditions in their patients,
or to just unusual situations
as far as patients are concerned.
We're going to talk about Considerations for Pediatric
Care, because children are different from adults.
We're going to talk about how to deal with
Thoracic Anesthesia and Thoracic surgery,
which is a very complex and potentially
quite dangerous area of anesthesia.
We're going to talk about Cardiac Anesthesia and how
we deal with open heart surgery. And we're going to talk
very briefly about Neuro-anesthesia, and the Different
Types of Anesthetic that may be necessary
to help patients through the sometimes extraordinarily
long operations. So we're going to start
with children. And if you think children are just
little adults, let me tell you, you're wrong.
They are very much different, from an anesthetic perspective
anyway, than adults. The anatomy is different,
the difficulties involved in managing them
are very different. And there are some risks
associated with Pediatric Anesthesia that are not
really associated with Adult Anesthesia.
The first thing that's critical to understand
is that the pediatric airway is quite
different from the adult airway. And I can tell you,
as I am an adult anesthesiologist, that
one of the things I dread is having to intubate a child,
particularly a child under two years of age.
And the reason for that is that
they are obligate nasal breathers,
so you can't depend upon them maintaining their airway
if you plug up their nose. They can't, they cannot breathe
through their mouths when they're very small. They have
proportionally a much larger tongue than adults.
They have proportionally a much larger
occiput, so it's difficult to extend the head
to the same degree as it is in adults.
The larynx and trachea are funnel shaped
with the narrowest point in the airway being
at the cricoid, whereas an adult's it's at the glottis,
at the opening of the glottis. The vocal
cords are on a funny angle in children and
it's hard for me to even describe it, because all I can
tell you is that they're hard to find, they're hard to see,
and unless you're very used to doing
children, it's very challenging. The larynx
is higher in the neck than it is in adults.
It's at the C4 level instead of the C6 level.
As I already mentioned, the narrowest part
of the pediatric airway is at the cricoid,
so when you go through the cords in a child, you
haven't hit the narrowest portion of the airway.
That comes next. And whereas in adults, the narrowest
point is at the chords, so any tube that it'll go comfortably
through the cords, is going to be fine. Whereas in children,
comfortably through the cords may still mean stuck
at the cricoid. The cricoid
in the child changes
at different times of life
and the narrow point remains the narrowest
point of the cricoid until age 4 – 5.
And then in adults, the glottis
the critical stricture point. The glottis
opening, the opening
of the larynx changes positions
over a childhood life,
so that it's quite high in the throat
in the premature babies, it's at
an intermediate area in toddlers
and newborns, and then it's much lower
in adults. This diagram shows you
the epiglottis. The epiglottis
is much more curved in a child than in
an adult. It's much stiffer than in an adult.
And it's harder to move. And you can see, it's harder
to see the cords. The cords are kind of off in
the distance and not as easy to identify as they
were in our earlier pictures of adult airways.