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| hongkongphooey 2005-04-05, 6:26 pm |
| How many times can you shock a patient suffering cardiac arrest with an
aed?
| |
|
| hongkongphooey wrote:
>
> How many times can you shock a patient suffering cardiac arrest with an
> aed?
Do you mean, "As long as the unit sees a shockable rhythm, how many times
will it discharge?"
Notan
| |
| Dave S 2005-04-05, 6:26 pm |
|
Notan wrote:
> hongkongphooey wrote:
>
>
>
> Do you mean, "As long as the unit sees a shockable rhythm, how many times
> will it discharge?"
>
> Notan
It depends on the manufacturer and the setting that it is used in, but
my experience has been that most AED's will only shock 6 times.. two
series of 3 shocks... during a single session.
Dave
| |
| Scott Aleckson 2005-04-05, 6:26 pm |
|
hongkongphooey wrote:
> How many times can you shock a patient suffering cardiac arrest with an
> aed?
>
Ask your medical director. Most AED's can be programmed for as many
shocks as the battery is capable of. Many protocols limit first
responders with an AED to 1 to 3 series of 3 stacked shocks. This will
vary by region. AEDs owned privately would have no restrictions.
| |
| Martyn H 2005-04-05, 6:26 pm |
| not the case in the UK - most UK AEDs will shock in the presence of a
shockable rythem nuntil the battery goes - hundreds of shocks if the
makers figures are correct on battery life
again it's down to protocols and whether the machine is likely to be
the 'only' defib for a significant period of time - a six shock limit
representing somethingless than 5 minutes of scene time is going to
look really good in the coroner's court when the ALS motor get delayed
, has an MVC , gets called to another call with NO resource on scene
.....
| |
| Dave S 2005-04-05, 6:26 pm |
|
Notan wrote:
> hongkongphooey wrote:
>
>
>
> Do you mean, "As long as the unit sees a shockable rhythm, how many times
> will it discharge?"
>
> Notan
It depends on the manufacturer and the setting that it is used in, but
my experience has been that most AED's will only shock 6 times.. two
series of 3 shocks... during a single session.
Dave
| |
| Scott Aleckson 2005-04-05, 6:26 pm |
|
hongkongphooey wrote:
> How many times can you shock a patient suffering cardiac arrest with an
> aed?
>
Ask your medical director. Most AED's can be programmed for as many
shocks as the battery is capable of. Many protocols limit first
responders with an AED to 1 to 3 series of 3 stacked shocks. This will
vary by region. AEDs owned privately would have no restrictions.
| |
| Dave S 2005-04-05, 6:26 pm |
|
Martyn H wrote:
> not the case in the UK - most UK AEDs will shock in the presence of a
> shockable rythem nuntil the battery goes - hundreds of shocks if the
> makers figures are correct on battery life
>
> again it's down to protocols and whether the machine is likely to be
> the 'only' defib for a significant period of time - a six shock limit
> representing somethingless than 5 minutes of scene time is going to
> look really good in the coroner's court when the ALS motor get delayed
> , has an MVC , gets called to another call with NO resource on scene
> ....
>
Actually, when you look at the FACTS regarding rescuscitation, I dont
think these arguments will hold water. While American Heart Association
is obviously in AMERICA, I would like to presume that much of the
clinical information they have is applicable to humans everywhere.
The longer an arrythmia persists, the more refractory to intervention it
becomes. Prolonged arrests rarely do well, and seldom leave the hospital
alive. (notice I did not say NEVER.. there are exceptions).
While prompt and early defibrillation is key to survival in sudden
cardiac death, so is early BLS and early advanced life support. Just
because you have a gadget that can shock someone for up to 20 or 30
minutes does not automatically confer any greater chance of survival.
After the first few rounds of shocks, intubation and drug therapy are
very appropriate and beneficial interventions.. but beyond the scope of
lay providers and some professional responders.
The reality is... if you want a good outcome, you need an otherwise
healthy patient, witnessed arrest, immediate CPR, defibrillation within
5 minutes or less (I believe AHA says 8 minutes) and appropriate post
resuscitation care. This requires an entire system, of which an AED is
only a small (but vital) portion of. There is something like a 30%
success rate for resuscitations that require CPR. This statistic
includes, and is DEPENDENT upon, the outcomes of those who arrest in a
monitored healthcare environment. When you look at soley out-of-hospital
arrests, the survival to discharge rates are dismal at best.
Not to mention.. if you REALLY think more shocks may be indicated, just
turn the damn thing off and back on again. The processor interprets this
as a "new patient" and can begin the cycle over again (if it was
programmed to have limits)
Dave
| |
| Martyn H 2005-04-05, 6:26 pm |
| while the data on early intervention is pretty soild, a system where
you create a false second patient ?
| |
| Dave S 2005-04-06, 8:49 am |
| What kind of system would send the closest ambulance responding to a
reported full-arrest situation on a different, later call?
When I was a dispatcher, I rerouted ambulances TO full-arrests, not AWAY
from them.
Dave
Martyn H wrote:
> while the data on early intervention is pretty soild, a system where
> you create a false second patient ?
>
| |
| Bernhard Nowotny 2005-04-08, 10:24 pm |
| Dave S schrieb:
> Martyn H wrote:
> Actually, when you look at the FACTS regarding rescuscitation, I dont
> think these arguments will hold water. While American Heart Association
> is obviously in AMERICA, I would like to presume that much of the
> clinical information they have is applicable to humans everywhere.
*smile*
> While prompt and early defibrillation is key to survival in sudden
> cardiac death, so is early BLS and early advanced life support. Just
> because you have a gadget that can shock someone for up to 20 or 30
> minutes does not automatically confer any greater chance of survival.
But if the patient is in vfib, he/she needs defib. If the AED then
limits the total number per one patient, it denies the possibility
that one and the same patient can get in troubles again a few
seconds after the last shock is done.
> After the first few rounds of shocks, intubation and drug therapy are
> very appropriate and beneficial interventions.. but beyond the scope of
> lay providers and some professional responders.
Is the AED in question a public access AED or part of the equipment
of a (medical trained) first responder team or even part of the
BLS/ALS-protocols? If latter, the numbers of possible shocks shouldn't
be limited at all but open to the provider's assessment.
> The reality is... if you want a good outcome, you need an otherwise
> healthy patient, witnessed arrest, immediate CPR, defibrillation within
> 5 minutes or less (I believe AHA says 8 minutes) and appropriate post
> resuscitation care. This requires an entire system, of which an AED is
> only a small (but vital) portion of. There is something like a 30%
> success rate for resuscitations that require CPR. This statistic
> includes, and is DEPENDENT upon, the outcomes of those who arrest in a
> monitored healthcare environment. When you look at soley out-of-hospital
> arrests, the survival to discharge rates are dismal at best.
BTW: What the hell with a limit anyway? The AED does it's work if there
is a vfib. If there is a vfib, then shock. Regardless of any other
situation.
I can't see a negative impact of too much shocks (in case of vfib). If
it works, it works. If not (including bad outcome), then it's not an
algorithmic problem of the AED.
What do you do with a patient in continuus vfib or re-occurring vfib?
I would shock once and again (according to resuscitation algorithm
beside the whole other stuff) until the defibs are effective or the
arrhythm some time later wents into asystole by itself (and then there
is time to consider stopping all care).
I see no sense in limits as long as someone proves that "too much
shocks" are not appropriate for resuscitation outcome. Even for
bystanders - what could they do wrong?
Only (strange) reason may be battery life of the AED. If shocks
are limited, you roughly could estimate the life time by number of
patients. But I don't think this counts as a real reason.
> Not to mention.. if you REALLY think more shocks may be indicated, just
> turn the damn thing off and back on again. The processor interprets this
> as a "new patient" and can begin the cycle over again (if it was
> programmed to have limits)
ACK. But if this is possible (and if the AED has not to be reset by
a key or such) then the whole programming of limits ist senseless
anyway...
--
Bernhard Nowotny Master of Systems Engineering
85625 Glonn, Germany (PGP ID: 0x17B6F58C DSS/DH)
"Life was simple before World War II. After that, we had systems."
-- Rear Admiral Grace Murray Hopper (documented first real computer bug)
| |
| Scott Aleckson 2005-04-08, 10:24 pm |
| > But if the patient is in vfib, he/she needs defib. If the AED then
> limits the total number per one patient, it denies the possibility
> that one and the same patient can get in troubles again a few
> seconds after the last shock is done.
>
While many AEDs do limit the number of shocks to certain arbitrary
standards, all models that I have encountered have an easy override to
this limit by those with the knowledge to do more for the patient...
shut it off (close lid, turn off switch, remove battery, etc), wait
about 10-15 seconds, then start over (your patches are already in place,
but you might need to unplug them prior to turning the unit on to trick
it into a new code). Cycling the power will reset the unit and you can
repeat shocks up to the maximum again (some will ask you to erase data
from the last rescue before starting a new patient, no problem, the MD
will live without all the code data). Repeat as needed until ALS arrives.
| |
| Anders Halling 2005-04-08, 10:24 pm |
| Scott Aleckson <nospam.aleckson@delete.alaska.net> writes:
>
> While many AEDs do limit the number of shocks to certain arbitrary
> standards, all models that I have encountered have an easy override to
> this limit by those with the knowledge to do more for the
> patient... shut it off (close lid, turn off switch, remove battery,
> etc), wait about 10-15 seconds, then start over (your patches are
> already in place, but you might need to unplug them prior to turning
> the unit on to trick it into a new code). Cycling the power will
> reset the unit and you can repeat shocks up to the maximum again (some
> will ask you to erase data from the last rescue before starting a new
> patient, no problem, the MD will live without all the code data).
> Repeat as needed until ALS arrives.
Silly, unnecessary and unhealthy for the patient.
Our AED's are programmed to give a series of three shocks,
and then ask for CPR for three minutes before a new series of
shocks. But this loop may continue untill the battery is dead.
As for the pt. data, I'd think the initial part of the data
is usually the most interesting. Our machines record data for
the first 20 minutes.
A.
--
We're not lost. We're locationally challenged.
-John M. Ford
| |
| Dave S 2005-04-08, 10:24 pm |
|
(SNIP)
> Silly, unnecessary and unhealthy for the patient.
>
> Our AED's are programmed to give a series of three shocks,
> and then ask for CPR for three minutes before a new series of
> shocks. But this loop may continue untill the battery is dead.
>
> As for the pt. data, I'd think the initial part of the data
> is usually the most interesting. Our machines record data for
> the first 20 minutes.
>
> A.
>
Thats all fine and dandy... but the reality is.. if you aren't
resuscitated within 10 or so minutes, you are HIGHLY unlikely to have a
good outcome or any chance of a meaningful recovery.
Yea, pedi cold water immersion prolonged rescus's have better odds, but
most of those are not in shockable rhythms to begin with.
So whats the point of having a device that can give shock after shock
for 30 minutes... it's one thing if you keep getting them OUT of a
shockably rhythm only to degenerate back INTO it.. but to remain in
intractible Vfib/tach? Geez...
Dave
| |
| Bernhard Nowotny 2005-04-08, 10:24 pm |
| Dave S wrote:
> Anders Halling wrote:
FullACK.
[vbcol=seagreen]
> Thats all fine and dandy... but the reality is.. if you aren't
> resuscitated within 10 or so minutes, you are HIGHLY unlikely to have a
> good outcome or any chance of a meaningful recovery.
> So whats the point of having a device that can give shock after shock
> for 30 minutes...
What's the point of limiting it by the AED-device? It should be
limited by the provider's common sense.
The AED is nothing but a device doing things a machine can do
more reliable than a human (studies show that diagnostics of
vfib are far more accurate and faster by the AED, the timing
is well done without my thinking and it certainly leads to a
more structured approach). But nothing more. I don't want to
be limited by this device.
And more so to be somewhat childlishly forced to fool it with
resets.
Event if it's a setting for random bystanders, I can't see a
real sense in it. Does a long series of shocks harm? No. It
mostly won't help much either, but that's not a decision,
that can be addressed by algorithms based only on number
of defibs.
> it's one thing if you keep getting them OUT of a
> shockably rhythm only to degenerate back INTO it.. but to remain in
> intractible Vfib/tach? Geez...
It's rare anyway. So no problem with it - if it's no vfib the
thing will not shock. Still no reason for limiting it generally.
--
Bernhard Nowotny Master of Systems Engineering
85625 Glonn, Germany (PGP ID: 0x17B6F58C DSS/DH)
"Life was simple before World War II. After that, we had systems."
-- Rear Admiral Grace Murray Hopper (documented first real computer bug)
| |
| Dave S 2005-04-08, 10:24 pm |
| What kind of system would send the closest ambulance responding to a
reported full-arrest situation on a different, later call?
When I was a dispatcher, I rerouted ambulances TO full-arrests, not AWAY
from them.
Dave
Martyn H wrote:
> while the data on early intervention is pretty soild, a system where
> you create a false second patient ?
>
| |
| Martyn H 2005-04-11, 6:13 pm |
| and if there isn't a resource to send to the other life threatening
incident?
becasue most of the world doesn't operate on a paid for item of
service health system where the prime determinant of coutcome and
treatment standards are ability to pay and /or closeness to the
'main' teaching hospital , we don't necessarily have huge numbers of
under utilised vehicles
there is also a organisational block to volunteer providers in much of
the UK EMS system which further compounds these problems
| |
| Dave S 2005-04-11, 6:13 pm |
|
(SNIP)
> Silly, unnecessary and unhealthy for the patient.
>
> Our AED's are programmed to give a series of three shocks,
> and then ask for CPR for three minutes before a new series of
> shocks. But this loop may continue untill the battery is dead.
>
> As for the pt. data, I'd think the initial part of the data
> is usually the most interesting. Our machines record data for
> the first 20 minutes.
>
> A.
>
Thats all fine and dandy... but the reality is.. if you aren't
resuscitated within 10 or so minutes, you are HIGHLY unlikely to have a
good outcome or any chance of a meaningful recovery.
Yea, pedi cold water immersion prolonged rescus's have better odds, but
most of those are not in shockable rhythms to begin with.
So whats the point of having a device that can give shock after shock
for 30 minutes... it's one thing if you keep getting them OUT of a
shockably rhythm only to degenerate back INTO it.. but to remain in
intractible Vfib/tach? Geez...
Dave
| |
| Bernhard Nowotny 2005-04-11, 6:13 pm |
| Dave S schrieb:
> Martyn H wrote:
> Actually, when you look at the FACTS regarding rescuscitation, I dont
> think these arguments will hold water. While American Heart Association
> is obviously in AMERICA, I would like to presume that much of the
> clinical information they have is applicable to humans everywhere.
*smile*
> While prompt and early defibrillation is key to survival in sudden
> cardiac death, so is early BLS and early advanced life support. Just
> because you have a gadget that can shock someone for up to 20 or 30
> minutes does not automatically confer any greater chance of survival.
But if the patient is in vfib, he/she needs defib. If the AED then
limits the total number per one patient, it denies the possibility
that one and the same patient can get in troubles again a few
seconds after the last shock is done.
> After the first few rounds of shocks, intubation and drug therapy are
> very appropriate and beneficial interventions.. but beyond the scope of
> lay providers and some professional responders.
Is the AED in question a public access AED or part of the equipment
of a (medical trained) first responder team or even part of the
BLS/ALS-protocols? If latter, the numbers of possible shocks shouldn't
be limited at all but open to the provider's assessment.
> The reality is... if you want a good outcome, you need an otherwise
> healthy patient, witnessed arrest, immediate CPR, defibrillation within
> 5 minutes or less (I believe AHA says 8 minutes) and appropriate post
> resuscitation care. This requires an entire system, of which an AED is
> only a small (but vital) portion of. There is something like a 30%
> success rate for resuscitations that require CPR. This statistic
> includes, and is DEPENDENT upon, the outcomes of those who arrest in a
> monitored healthcare environment. When you look at soley out-of-hospital
> arrests, the survival to discharge rates are dismal at best.
BTW: What the hell with a limit anyway? The AED does it's work if there
is a vfib. If there is a vfib, then shock. Regardless of any other
situation.
I can't see a negative impact of too much shocks (in case of vfib). If
it works, it works. If not (including bad outcome), then it's not an
algorithmic problem of the AED.
What do you do with a patient in continuus vfib or re-occurring vfib?
I would shock once and again (according to resuscitation algorithm
beside the whole other stuff) until the defibs are effective or the
arrhythm some time later wents into asystole by itself (and then there
is time to consider stopping all care).
I see no sense in limits as long as someone proves that "too much
shocks" are not appropriate for resuscitation outcome. Even for
bystanders - what could they do wrong?
Only (strange) reason may be battery life of the AED. If shocks
are limited, you roughly could estimate the life time by number of
patients. But I don't think this counts as a real reason.
> Not to mention.. if you REALLY think more shocks may be indicated, just
> turn the damn thing off and back on again. The processor interprets this
> as a "new patient" and can begin the cycle over again (if it was
> programmed to have limits)
ACK. But if this is possible (and if the AED has not to be reset by
a key or such) then the whole programming of limits ist senseless
anyway...
--
Bernhard Nowotny Master of Systems Engineering
85625 Glonn, Germany (PGP ID: 0x17B6F58C DSS/DH)
"Life was simple before World War II. After that, we had systems."
-- Rear Admiral Grace Murray Hopper (documented first real computer bug)
| |
| Dave S 2005-04-11, 6:13 pm |
|
Martyn H wrote:
> not the case in the UK - most UK AEDs will shock in the presence of a
> shockable rythem nuntil the battery goes - hundreds of shocks if the
> makers figures are correct on battery life
>
> again it's down to protocols and whether the machine is likely to be
> the 'only' defib for a significant period of time - a six shock limit
> representing somethingless than 5 minutes of scene time is going to
> look really good in the coroner's court when the ALS motor get delayed
> , has an MVC , gets called to another call with NO resource on scene
> ....
>
Actually, when you look at the FACTS regarding rescuscitation, I dont
think these arguments will hold water. While American Heart Association
is obviously in AMERICA, I would like to presume that much of the
clinical information they have is applicable to humans everywhere.
The longer an arrythmia persists, the more refractory to intervention it
becomes. Prolonged arrests rarely do well, and seldom leave the hospital
alive. (notice I did not say NEVER.. there are exceptions).
While prompt and early defibrillation is key to survival in sudden
cardiac death, so is early BLS and early advanced life support. Just
because you have a gadget that can shock someone for up to 20 or 30
minutes does not automatically confer any greater chance of survival.
After the first few rounds of shocks, intubation and drug therapy are
very appropriate and beneficial interventions.. but beyond the scope of
lay providers and some professional responders.
The reality is... if you want a good outcome, you need an otherwise
healthy patient, witnessed arrest, immediate CPR, defibrillation within
5 minutes or less (I believe AHA says 8 minutes) and appropriate post
resuscitation care. This requires an entire system, of which an AED is
only a small (but vital) portion of. There is something like a 30%
success rate for resuscitations that require CPR. This statistic
includes, and is DEPENDENT upon, the outcomes of those who arrest in a
monitored healthcare environment. When you look at soley out-of-hospital
arrests, the survival to discharge rates are dismal at best.
Not to mention.. if you REALLY think more shocks may be indicated, just
turn the damn thing off and back on again. The processor interprets this
as a "new patient" and can begin the cycle over again (if it was
programmed to have limits)
Dave
| |
| Martyn H 2005-04-11, 6:13 pm |
| while the data on early intervention is pretty soild, a system where
you create a false second patient ?
| |
| Scott Aleckson 2005-04-11, 6:13 pm |
| > But if the patient is in vfib, he/she needs defib. If the AED then
> limits the total number per one patient, it denies the possibility
> that one and the same patient can get in troubles again a few
> seconds after the last shock is done.
>
While many AEDs do limit the number of shocks to certain arbitrary
standards, all models that I have encountered have an easy override to
this limit by those with the knowledge to do more for the patient...
shut it off (close lid, turn off switch, remove battery, etc), wait
about 10-15 seconds, then start over (your patches are already in place,
but you might need to unplug them prior to turning the unit on to trick
it into a new code). Cycling the power will reset the unit and you can
repeat shocks up to the maximum again (some will ask you to erase data
from the last rescue before starting a new patient, no problem, the MD
will live without all the code data). Repeat as needed until ALS arrives.
| |
| Dave S 2005-04-11, 6:13 pm |
| What kind of system would send the closest ambulance responding to a
reported full-arrest situation on a different, later call?
When I was a dispatcher, I rerouted ambulances TO full-arrests, not AWAY
from them.
Dave
Martyn H wrote:
> while the data on early intervention is pretty soild, a system where
> you create a false second patient ?
>
| |
| Anders Halling 2005-04-11, 6:13 pm |
| Scott Aleckson <nospam.aleckson@delete.alaska.net> writes:
>
> While many AEDs do limit the number of shocks to certain arbitrary
> standards, all models that I have encountered have an easy override to
> this limit by those with the knowledge to do more for the
> patient... shut it off (close lid, turn off switch, remove battery,
> etc), wait about 10-15 seconds, then start over (your patches are
> already in place, but you might need to unplug them prior to turning
> the unit on to trick it into a new code). Cycling the power will
> reset the unit and you can repeat shocks up to the maximum again (some
> will ask you to erase data from the last rescue before starting a new
> patient, no problem, the MD will live without all the code data).
> Repeat as needed until ALS arrives.
Silly, unnecessary and unhealthy for the patient.
Our AED's are programmed to give a series of three shocks,
and then ask for CPR for three minutes before a new series of
shocks. But this loop may continue untill the battery is dead.
As for the pt. data, I'd think the initial part of the data
is usually the most interesting. Our machines record data for
the first 20 minutes.
A.
--
We're not lost. We're locationally challenged.
-John M. Ford
| |
| Dave S 2005-04-11, 6:13 pm |
|
(SNIP)
> Silly, unnecessary and unhealthy for the patient.
>
> Our AED's are programmed to give a series of three shocks,
> and then ask for CPR for three minutes before a new series of
> shocks. But this loop may continue untill the battery is dead.
>
> As for the pt. data, I'd think the initial part of the data
> is usually the most interesting. Our machines record data for
> the first 20 minutes.
>
> A.
>
Thats all fine and dandy... but the reality is.. if you aren't
resuscitated within 10 or so minutes, you are HIGHLY unlikely to have a
good outcome or any chance of a meaningful recovery.
Yea, pedi cold water immersion prolonged rescus's have better odds, but
most of those are not in shockable rhythms to begin with.
So whats the point of having a device that can give shock after shock
for 30 minutes... it's one thing if you keep getting them OUT of a
shockably rhythm only to degenerate back INTO it.. but to remain in
intractible Vfib/tach? Geez...
Dave
| |
| Martyn H 2005-04-12, 11:47 am |
| and if there isn't a resource to send to the other life threatening
incident?
becasue most of the world doesn't operate on a paid for item of
service health system where the prime determinant of coutcome and
treatment standards are ability to pay and /or closeness to the
'main' teaching hospital , we don't necessarily have huge numbers of
under utilised vehicles
there is also a organisational block to volunteer providers in much of
the UK EMS system which further compounds these problems
| |
| Dave S 2005-04-13, 4:43 pm |
|
(SNIP)
> Silly, unnecessary and unhealthy for the patient.
>
> Our AED's are programmed to give a series of three shocks,
> and then ask for CPR for three minutes before a new series of
> shocks. But this loop may continue untill the battery is dead.
>
> As for the pt. data, I'd think the initial part of the data
> is usually the most interesting. Our machines record data for
> the first 20 minutes.
>
> A.
>
Thats all fine and dandy... but the reality is.. if you aren't
resuscitated within 10 or so minutes, you are HIGHLY unlikely to have a
good outcome or any chance of a meaningful recovery.
Yea, pedi cold water immersion prolonged rescus's have better odds, but
most of those are not in shockable rhythms to begin with.
So whats the point of having a device that can give shock after shock
for 30 minutes... it's one thing if you keep getting them OUT of a
shockably rhythm only to degenerate back INTO it.. but to remain in
intractible Vfib/tach? Geez...
Dave
|
| |
|
|