all righty good morning everybody thank
you very very much for coming out here
and the you know the world of stroke has
come a huge way because when I first
started speaking about stroke
I had audience as well in the 4 to 6
people range and this is really
tremendous all righty so I just wanted
to let you know that I have only one
major disclosure and that is that I'm
very honored to be here today with my
colleagues and with all of you so thank
you all for coming I'd like to talk a
little bit about emergency medicine
pre-hospital systems and and kind of the
screening tools that they use in the
pre-hospital environment and to kind of
figure out you know how they actually
make decisions on who to transport where
and when and what time frame and and so
you know clearly 12 minutes is more than
enough to discuss this topic and you'll
understand why at the end so we all kind
of are here because we know that strokes
are fairly common that that there's a
fairly high mortality with strokes it's
a number two killer in the world and
it's number four in the United States
and that there's a significant morbidity
to it and that morbidity it translates
to six and a half million stroke
survivors in the United States and
really the amount of disability that it
causes is really our major problem in
managing strokes and so all of our
effort really is to decrease the
disability as well as do our best to
decrease mortality in the acute stroke
patients we also know that that was a
large vessel occlusion and LVO which is
becoming you know the term that we all
hear on a daily basis that that you have
severe ischemia to the brain and that
this ischemia is very time dependent and
that you lose about 1.9 million neurons
per minute in a large vessel occlusion
one about 14 billion synapses and and
then about seven and a half miles of
axonal fibers per minute of occlusion so
time is clearly very important now
having that back
I would just like to kind of go over for
those of you that don't live in the EMS
world you know how things are organized
in in EMS it kind of started back in the
60s and 70s when people realized that
your chances of dying from a motor
vehicle accident on the highway was
greater than if you had gotten shot in
combat in Vietnam and and from that
point they said we really have to do
something about this and back then the
ambulances were also hearses and they
were just you know large station wagons
and and that was the extent of our ems
system and was very informal so there
was legislation passed in 1966 and again
in 73 the big ems Act of 1973 created
our ems systems but these systems are
under local control and the state each
state creates local regions called MCAS
and the MCAS our medical control
authorities and they're made up the
medical control authorities themselves
are made up of all the hospitals in that
region that actually have their doors
open 24/7 to receive patients and so
these committees in each region make up
all of their protocols and certain rules
but then those are supervised by the
state so that there's some consistency
and some minimal correlation to what the
state wants for EMS care the funding for
these things out varies a you know
extremely widely from community to
community it could be public could be
private or could just be volunteer
services and the way they're organized
is extremely variable based on their
resources so in some communities you
have people that are both firemen and
paramedics and other places those two
are separate and the amount of training
for paramedics varies tremendously also
the other thing is that they work on
protocols and the protocols may be
either online meaning that there's a
physician on the phone or through some
kind of telemetry process with them or
they could just be run by protocols were
where the paramedics go in the field and
just run what they do based on on pre
established protocols so the training
for these people is extremely variable
and if you take a look around the Unites
States there's over 30 types of
paramedics that are operating out in the
field but we kind of divide them into
kind of three levels a basic which has
about a hundred hours of training and
this person can go out and do CPR
intubate and they have a DS with them
these automatic defibrillators
intermediate who can do a little more
they have 300 hours of training and they
can do IVs and certain medications and
EKGs and then a full paramedic with over
a thousand hours of training that can
has extended use of medication so it
depends on the resources or the
individual community that you live in
that actually dictates what the level of
training is for your pre-hospital care
personnel so I'd like you to kind of
imagine yourself sitting in your living
room watching the Lions game and clearly
you know I know these guys aren't
watching the Lions because they're all
smiling and so I know that this is a
little bit of a stretch however assume
that you're kind of on a Sunday
afternoon at home with your family
watching watching TV hanging out and all
of a sudden you have a stroke and and
you can't move and you and you can't
talk and you're not really sure what's
going on you know what is it that you
would like to happen if you were stuck
in that position you know and and I
think that that putting yourself in to
the patient's point of view kind of
helps you develop ideas about what we
should do to respond to patient care
needs and that's kind of a real panic
situation and what you're hoping for is
that somebody recognizes that you're not
right even if you can't you know really
talk and it's and it's very different
it's not like a heart attack where you
can go oh my god my chest is hurting or
you know or if you got shot and you're
you know dripping blood on the floor
people notice and so you want to make
sure that your family members know
what's going on and that you get their
attention and that they actually call
9-1-1 and that when they call 9-1-1 the
person who's answering the phone at
night and when the dispatcher
understands that this could be a stroke
and that you actually
get the right resources out to that
patient and that the paramedics or the
EMS people get there very fast and that
once they're there they figure out
what's going on and get you and maybe a
family member to the right place
so getting you know the right person to
the right place and the right time is
absolutely key and you know recognizing
the symptoms is not as easy as you think
and we kind of struggle with this all
the time if you have a mi you know you
have an EKG that tells you exactly
what's going on and you have patients
with symptoms and if you get stabbed or
shot you know you have obviously the
trauma that that gets you in and this
this young man who was eviscerated was
actually a patient that I took care of
and of course you know when he got
stabbed and he eviscerated on the street
everybody you know noticed it and
panicked and called EMS and we got all
these systems going we got you know the
trauma surgeons anesthesia a
resuscitation room and we basically took
the guy up and and you you know run his
bowel and rinse them out and tuck it
back in and they have a two percent
mortality and with the stroke patients
you may have up to a twenty percent
mortality at one year and nobody's
really kind of you know getting in a
rush or panicking so I think that with
the current treatments we have we need
to change that paradigm so you want your
people to actually recognize that
there's something wrong with you and and
that's the face arm speech and time kind
of thing and hopefully they'll learn
about that and you want them to call 911
barsen many years ago actually figured
out that if you call 9-1-1 that's the
fastest way to get into the emergency
department and that if you call your
private physician that's the slowest way
to get into the emergency department and
yet that's kind of you know your natural
reflex is to call your doctor so that
you kind of have to change that a little
bit so our expectations of EMS are that
they actually get there in time they
figure out what's going on with the
patient and get them to the right place
the dispatchers really need to use very
focused questions to get to the bottom
of what's happening with the patient so
that they can tell the paramedics you
know what kind of run they're on
they can prepare for it and really one
of the most difficult things is to
figure out when was the patient last
normal so if you're sitting in your
living room
and you can't speak and you can't move
nobody notices that there's something
wrong so so they'll have to go back
oh yeah right you know half hour ago he
got up and went to the bathroom and
that's that now that becomes your time
so once the paramedics get there they
have to deal with the ABCs the airway
breathing circulation and they actually
look at your c-spine also to make sure
that there's no Associated trauma with
this they check your glucose you know
and then they then they may operate on a
protocol or they may call in they also
have to kind of do some kind of
pre-hospital stroke scale and there are
two kinds one that actually helps you
identify a stroke and one that actually
tries to help you identify if there's a
large vessel occlusion or not and as you
can see there's a ton of these things
out there and so this slide is not
intended for you to really understand
any of these things whereas this slide
is so and so you can see that all of
these scales have been tested they all
have their sensitivities and
specificities likelihood ratio is a
positive and negative you know and and
they all kind of compete with each other
for you know which is the best one but
the fact that there's so many of them
means that none of them are really
sufficiently adequate to do what you
really want to do which is you know you
need a psychic with you to know if
there's a a large vessel occlusion when
you first show up at the patients house
so so really you have to kind of look at
these and I know that over time there's
going to be more and more data on this
there's a couple validated ones the
Cincinnati pre-hospital Stroke Scale in
the Los Angeles pre-hospital stroke
screen that have undergone some testing
and Steve Levine's group has kind of
done these graphs and looked at all the
data on them and has created receiver
operator curves that tell you how good
their sensitivity is and how low their
false positive rates can go and you know
that the laps score the Los Angeles
pre-hospital Stroke Scale has 86 percent
sensitivity and a 99 percent
specificity which i think is really you
know pretty good
Cincinnati though is much much more
simple it's not an 11 item score it's a
three item score and it's at 80 percent
sensitivity and 88 percent specificity
so I think for for that scale being as
simple as it is it's really quite
effective and so this is the to
comparison so when pink is the LA Stroke
Scale and and in blue is a Cincinnati
Stroke Scale and you can see these are
all various studies that have mapped out
their various characteristics so it's
not really important to know this right
now but what's important to know is that
the American Heart has come up with an
algorithm that basically says when EMS
arrives they have to examine the patient
and they should do some kind of screen
to actually decide if it's a stroke and
then if you think it's a stroke you
should do a screen to decide if it's a
larger vessel occlusion and if it's a
large vessel occlusion and they're
within six hours and that paradigm is
changing and we'll hear more about that
today
then you should transport them to an
institution that actually can do a
thrombectomy and has endovascular
therapy if it only adds another 15
minutes of transport on to your already
usual transport time and so that's kind
of the American Heart algorithm and
they've worked on this for a long time
and there's data supporting each box in
each circle but I think one of the
interesting things that has just
recently developed is something that was
published just recently by Andrew
ASIMO's in North Carolina and Bogle
who's a epidemiologist and they
basically created a simulation and so
they know that the person is going to
call 9-1-1 EMS is going to be dispatched
and that when they arrive they're going
to do a unseen score and look for an LV
oh and if it's not there they're gonna
transport to the nearest hospital it if
it is there they're going to transport
to the nearest endovascular center and
in this model what you can do is
actually look at your stroke prevalence
in your county and create simulations
for various patients based on where
they're you live what their odds are of
having a
stroke and then you can actually plug in
various different transport times
various different times of day and then
they were use MapQuest to figure out
what the transport times will be and
then you can use various different
stroke scales so you can actually use
this model for your own community and
they actually looked at two counties
Mecklenburg County which is Charlotte
North Carolina and then King County
which is Seattle and Seattle has a fair
amount of mountainous regions around it
that are hard to transport and and they
tried to figure out there over triage
rate which is how many people are you
gonna actually over triage to
endovascular centers that could have
gone to their local or their closest
Primary Stroke Center and the over
triage rate for Mecklenburg County was
between 13 and 55% and for King County
was 10 to 40% and it's interesting that
you can't make a single statement about
everybody in the country what you can
say is that every environment is
different and you need to figure it out
in that environment and model for that
environment and they came up with this
know like number needed to route so how
many people do you need to route to a
center that can do endovascular therapy
in order to get one LVO patient there
and so using the lambs score it was
about 2.6 using the race scores about
5.3 and using SI stat which is another
Cincinnati scale it was nine point three
and so depending on your environment
right because Cincinnati wants everybody
to come to them and so but the thing is
that you have to decide what's an
acceptable false positive rate how many
LV OS are you willing to send to places
that don't have endovascular so
ultimately as I finish up here with my
conclusion there's an extreme
variability in systems
there's no consensus on which stroke
scales to use you have to get involved
it took five years to do the TPA study
and 20 years to implement it so get
working and as a transition I would just
like to say the big parameters are on
set to reperfusion and it's an entire
system and so we're hopefully going to
hear about how to cut that system short
by field treatment thank you
[Applause]