00:01
The last kind of neurologic
insult I want to talk about
is death by neurologic criteria.
00:07
So this was previously
known as brain death.
00:10
The difficulty with
calling it Brain death
is that it sort
of differentiates,
well, some people will
interpret that as well,
the brain is dead, but the
rest of the body is alive.
00:20
When this has been
worked out and intubated,
over the past 30 years or so,
it's an idea that
the person has died.
00:30
It's just that neurologic criteria
being used to determine death,
rather than, what
the historic pattern
has been was
cardiopulmonary death.
00:41
So here,
because person
hood has been lost,
because the overall integrative
functions of the brain
are no longer working.
00:50
The person has died
and we call this death
by neurologic criteria.
00:56
So there has to be
absence or complete,
you know, cessation, and
has to be irreversible,
of both cerebral and
brainstem function.
01:05
So they're going to be various
tests that are going to be done
to demonstrate that there is no
cerebral or brainstem functioning.
01:13
The person when they're
in this condition,
are going to have an
irreversible coma.
01:18
And it has to be the
result of some known
central nervous
system catastrophe.
01:23
So whether it's been trauma,
whether it's been
a massive stroke,
whether it's been, you know,
they had a cardiac arrest,
and didn't get any
oxygen up to their brain
for a long period of time,
any kind of insult like that,
that you know has resulted
in irreversible coma.
01:43
Next, you have to make sure
that there are no other
complicating medical conditions
that might be bearing
on whether or not
they've got neurologic function.
01:53
So, are there any
toxins in their system
that might be affecting
brain function?
Is the body so cold,
that it can't function.
02:02
And if you warm the body up,
some neurologic function
might come back.
02:08
So you need to know are there
electrolyte abnormalities
that need to be corrected.
02:13
Various things,
make sure that there are no other
complicating medical condition,
you've excluded those
and that it's because
of the brain injury,
that there's this
irreversible coma
and loss of cerebral
and brainstem function.
02:27
So you're going to
need to do tests
to show that there's an absence of
brain originating motor responses.
02:33
So some of the
things of the stimuli
that might give to see if there's
going to be a motor response,
and there's no response by
the body to those things.
02:43
Because there's loss
of brainstem function,
you also have to demonstrate that
there's no respiratory drive.
02:48
So there's going to be
no spontaneous breaths.
02:51
If the person is
on a ventilator,
they don't breathe
over the ventilator.
02:55
If you turn off the ventilator
and let their oxygen level drop
in their carbon
dioxide level rise,
that there's no evidence
that that stimulates
the person to the body
to start breathing.
03:08
And then lastly, you do
various neurologic tests
to show that there's an
absence of brainstem reflexes.
03:14
So these are typically done by
these testings for brain death
or death by neurologic criteria
are done by neurologists,
neurosurgeons, intensivist,
that have very
specific skill set
of how to diagnose definitely
neurologic criteria.
03:33
The reason that this
has become important
over the past few decades
is because patients
that are declared dead
by neurologic criteria
can be organ donors.
03:43
So there's the opportunity
if they are now deceased,
that they might be able
to donate their organs
or their family donate
their organs on their path
for use in transplantation.
03:56
So this is just one instance of
the clinicians role
of determining death,
and then deciding what
happens to the person's body
after their death.
04:07
So it's important to be aware
of these neurologic conditions
because they do bear on
decision making with families.
04:13
For instance, in persistent
vegetative state,
there may be questions
of whether or not to
provide artificial
nutrition and hydration
and minimally conscious state.
04:23
There may be patients that say,
if I really have minimal
awareness of my environment,
I may not want to be kept
alive in that situation.
04:30
And for death by
neurologic criteria.
04:32
That's really a decision that,
the clinicians have to come to,
do the appropriate testing,
and then share that information,
the diagnosis of
death with the family.
04:43
All very challenging situations,
bears on our clinical
acumen or clinical judgment,
but it does speak to
clinical ethics as well.