prefer this technique to using an endobronchial tube.
So dislodgement of the endobronchial tube
or the blocker is unfortunately relatively
common. And results in loss
of one-lung ventilation, it can result
in a drop in oxygen saturation
and it means you have to put the bronchoscope down again
and try to reposition everything. The problem is, that when
the surgeon's got a deflated lung and is working on that lung,
there's a lot of movement and the anatomy that
you're used to seeing is completely distorted by the fact
that there's only one lung now. So, it's difficult.
And it requires people with special skill. If you are
doing one lung anesthesia and the patient
begins to become hypoximic, you can't
just take out the tube or start ventilating
the other lung in the hope that you can get
them back to a normal state. You can talk
to the surgeon, and in some cases the surgeon will say,
“Okay, I'll try to do the surgery with a ventilated
lung. I'll try to do the surgery while the lung's moving.
so go ahead and ventilate.” That's usually not the case.
Usually what they ask you to do is, “Do something
to fix it!” And what the anesthesiologist does
in this case to attempt to fix it, is apply PEEP, or
positive end-expiratory pressure, to the ventilated
lung. So in other words, never let the lung completely
collapse on expiration! Keep some back pressure
on at all the time, which increases the volume of the lung
and allows gas exchange to occur during
expiration, and also consider putting CPAP
on the operated lung. So, just some
pressure on the operated lung. It'll inflate a little bit, but
won't inflate all the way, and it won't move with ventilation,
It'll inflate to a point and then just stop, it won't go up
and down like this. And the surgeons can tolerate
that and can continue with their work. And that'll
often allow better gas exchange and improve
the situation. Massive hemorrhage
is a very unfortunate
and sometimes deadly complication of thoracic surgery
and anesthesia. It's extremely difficult to manage.
You are totally dependent on the surgeon
trying to get control of the bleeding,
and the person who sees most of the bleeding is the anesthesiologist,
because what happens is, the blood comes up
the endo, not up the endobronchial tube, but up the trachea.
It will come up the endobronchial tube and there's always
a danger that some of that blood will get over into the other
lung and contaminate that long, and make oxygenation
that much more difficult. It's a very difficult
thing to deal with. Post-operative
acute lung injury is potentially a lethal combination
in these patients, and it's often not predictable.
So, when we have an elderly patient with really
bad lungs, we look at each other and we say,
“You know, this may not turn out too well, because this
patient's got a high probability of developing an acute
lung injury and have to go to the ICU.” In fact, we may be
completely wrong, they may fly through the surgery without
any difficulty at all, and another patient who
is younger and healthy may develop ALI.
Post-operative pain management is crucial, as thoracic
anesthesia pain is the worst of all surgical pains.
And it's vital that these patients breathe deeply
and cough post-operatively. And if you don't use
appropriate pain management, they 'splint' their
chest and try not to move the chest wall.
The placement of a thoracic epidural can
completely remove pain, and allow patients
to deep breath, to cough and to ambulate.
And this has been a huge improvement
in care for these patients over the last 10
or 15 years. So, this is a thoracotomy
incision. And what you're looking at there,
if you look at the forceps that's coming in
from the right side of the picture, it's going behind
one of the lobes of the lung, and the surgeon's
working on that lobe. And above it, you can see a
kind of a purple blob. And that purple blob
is uninflated lung tissue. Inflated lung
tissue, number one, takes a lot more
space than that, and number two, is pinkish in color, it's not
purple. But when it's deflated, it looks like liver. And that's
what's happened here is, you've got the surgeon
working on lung in a successfully
deflated one-lung anesthetic situation. We're
going to move now to Cardiac Anesthesia,