X-Message-Number: 32730
From: "sbharris1" <>
References: <>
Subject: Re: CryoNet #32726 Why ECLS is uncommon
Date: Thu, 22 Jul 2010 16:58:07 -0700

----- Original Message ----- 
> Message #32726
> From: Darryl Metz <>
> Subject: Perfusion during cardiac arrest ?
> Date: Wed, 21 Jul 2010 22:50:07 -0700
>
> --_7662365d-090a-4748-9412-ef21646381bf_
>
>
> I read some posts from earlier this month in which it was said that teams
exist in hospitals that can attach patients in cardiac arrest to portable
perfusion machines. It was suggested that these teams could be used in
cryonics. That left me wondering why such teams aren't used routinely in
hospitals. Why on TV shows do we see doctors doing futile CPR and then
calling "time of death" rather than attaching patients to perfusion machines
while their hearts are stopped to buy more time?
>
> Darryl



COMMENT: from Steve Harris



The short answer is because hardly any hospitals have such teams. Despite
the suggestion on this list that SOME do, based apparently on the fact that
very occasionally, cardiologists who have some arrest in the cath lab can
get a perfusionist and open-heart surgical team assembled in time to save
somebody. Such really advanced stuff is NOT available to your average
patient getting advanced cardiac life support (ACLS) with chest compressions
in the ICU or wards of an average hospital, let alone anywhere outside a
hospital. So, you're right-- it's very experimental and not standard of
care.



In the future, might it arrive as a new standard of care? Who knows? There
are all the same economic problems with it that we've discussed with
cryonics. The hospital thinking about it must have shifts of perfusionists,
cardiologists, and surgeons sitting around inside the hospital (or very
near), waiting to run a portable bypass machine to the arrested patient
bedside, for emergency "extracorporeal life support  (ECLS). This is
expensive. Occasionally it has been reported to work to save somebody in
refractory cardiac arrest in sites that have experimented with it, but it
hasn't caught on. Even the places that do it, report tiny numbers. The
biggest series I can find is (PMID: 20176219) reports just 150 total cardiac
arrest patients treated with ECLS, over a *20 year* span. This is with a
dedicated team and many generations of ECLS equipment! This rate of 7
patients/year should be seen against the far larger number of patients per
year who must die after ACLS resuscitation attempts, at this center (the
Sharp Memorial/San Diego Cardiac Center), as would be the case in any
cardiac center.



Looking at it another way: there are roughly 350,000 sudden cardiac arrests
a year in the US. If 5% of them occur in hospitals, or arrive to hospitals
in resuscitatable condition, this would still be 17,000 ACLS hospital codes,
and a large fraction of these would be candidates for ECLS. They're not
getting it. Rather, the literature reports mere handfuls per year, even in
centers where emergency bypass is available.



Worse still, typically, such studies report only in terms of patients who
have been successfully placed on ECLS, not in terms of total patients in
whom it was *attempted.* That's a sort of cherry-picking that cryonics
cannot do. As example: in one small series (PMID:15620939) of ECLS for
cardiac arrest patients in France (40 patients over 5.5 years, again
demonstrating the slow pace and careful patient choice), the mean patient
age was 42. Clearly, these are not the elderly dehydrated hospice patients
who often come to cryonics. Just as clearly, they are only a very tiny and
carefully-chosen fraction of total candidates. I don't think such numbers
can be used to infer anything about the availability of ECLS, or the
potential usability of the ECLS experimental model (such as it is) for
cryonics.



There are other indications of the difficulties of ECLS. For example,
observe the very small numbers of prospective series and their bad results.
A French study (PMID: 173442517) of ECLS in an ICU started with 17 patients,
but achieved ECLS in 14 of them, with complications of 8 massive bleeds in
these, and need for surgical revision in 1.  Another study of 33 ECLS
patients collected over 4 years (8 patients a year) is at:
http://ats.ctsnetjournals.org/cgi/content/full/71/3_suppl/S77

In this study, one of the patients died of technical delays due to
"technical difficulties at cannulation.   In the others, the report states:
"Venous drainage was obtained by right internal jugular cutdown in 10
patients, percutaneous femoral vein cannulation in 20 patients, and right
atrial cannulation in 1 patient. Arterial and venous cannulation sites were
chosen based on the urgency of establishing circulatory support.   So the
femoral vessels alone were not found adequate in a third of these patients,
when starting on an intent-to-treat basis. But that's all you have to go on,
when deciding how hard this SHOULD be, in cryonics (given some ideal
professional teams standing by round-the-clock).



ECLS is hard. If it were easy, it would be the standard of care most places
for cardiac arrest patients unresponsive to ACLS, and it is not even close
to that. Yes, ECLS is a bit easier in "cath lab  patients (those undergoing
angiography), but almost all of these, by definition, have a femoral
catheter placed already (allowing arterial perfusion access over a
guide-wire, if need be). All studies of ECLS that have looked at location of
procedure, find that it's more effective for cath lab patients. Again, not a
luxury cryonics has.



Only something like 25% of the country's 5000 hospitals have such 24 hour
seven day a week 365 day a year available cath labs. These are the
"ST-Elevation MI  or "STEMI  centers for emergency cath lab procedures like
stents and balloons. But even in this subset of technically-ready centers,
the availability of ECLS for resuscitation patients in the rest of the
hospital, is quite rare. This is not for lack of a perfusionist. Most
(though not all) of these 24-hour cath labs have emergency heart surgical
backup, and therefore some sort of on-site or on-call emergency perfusionist
availability. However, even so, this is generally only available to cardiac
arrests that happen under the hands of an interventive cardiologist.  For
everyone else, even in these best cath-lab hospitals, they're out of luck.
Of course that's also true in the other > 75% of hospitals, and in hospices,
rehab centers, nursing homes, and so on. Cryonics can't just be done in
STEMI centers.



Thus, the suggestion that cryonics could potentially make available to its
members emergency bypass by a surgeon and perfusionist-- something that isn'
t available even to the average U.S. hospitalized patient, is almost
self-evidently wrong. If it were possible at a reasonable price, it would
*already* be offered as the last stage of ACLS by our standard medical
system (which has been trying to do it for more than 20 years), and of
course it isn't (the studies above are small demos, generally with no
intent-to-treat statistics). If somebody thinks this kind of thing can be
generally offered, they have (as I count it) as many as 1250 PCI-diversion
hospitals and their attendant cardiac surgical/perfusion teams in the US, to
convince to simply do it. I wish people who think this can be economic would
start there in the standard medical system, and leave cryonics alone until
they've demonstrated that the large scale system, already in place, can be
improved in this fashion.



Tell us where it's being done. Tell us how many patients they've done. Give
your references. I can't prove a negative, but people claiming the present
workability of general ECLS for a whole prospective population, have the
responsibility of giving your numbers.

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