X-Message-Number: 31140
Date: Thu, 6 Nov 2008 07:20:43 -0800 (PST)
From: Julian Conrad <>
Subject: "Ice slurry" adaptable for cryonics purposes?

http://www.anl.gov/Media_Center/News/2008/NE081031.html
http://www.anl.gov/Media_Center/News/2008/NE081031.pdf

Technical article:

http://www.ne.anl.gov/capabilities/sinde/biomed/IceSlurryCooling.pdf

Ice slurry technology can save heart attack victims,
surgery patients 

ARGONNE, Ill. (Oct. 31, 2008) - When treating cardiac
arrest victims, doctors can't call a time-out. Without
the ability to obtain fresh oxygen from blood pumped
through the body, brain cells start to die in just
minutes. Within 10 to 20 minutes after the heart stops
beating, the clock has run out. Even if doctors can
get the heart ticking again, the brain has died.

Recently, however, researchers have begun to develop a
new technique that can reduce the brain and other
organs' demand for oxygen, giving doctors precious
extra time to diagnose and treat critical patients in
emergencies while also protecting the heart, brain,
kidneys and spinal cord in planned surgeries.

Scientists in the Nuclear Engineering Division at the
U.S. Department of Energy's Argonne National
Laboratory have created an ice slurry - a slushy
substance that somewhat resembles a 7-11 SlurpeeR.
This slurry can be pumped easily into the body through
a small intravenous (IV) catheter directly into a
patient's bloodstream.

Argonne is working with the several different groups
of University of Chicago surgeons to develop
procedures for cooling and protecting vital organs.
This research is being conducted under a newly formed
University of Chicago-Argonne Bioengineering Institute
for Advanced Surgery and Endoscopy (BIASE).

Argonne researchers designed and patented the
equipment used to produce the slurry, which is
delivered into the body by specially designed tips.
Doctors can quickly chill the targeted organ by
choosing one of several possible routes for the slurry
based on the condition to be treated. This cooling
reduces an organ's need for oxygen, slowing the rate
at which cells asphyxiate and providing doctors more
time for treatment.

In the case of a victim who suffered cardiac arrest
out of a hospital, the slurry would be delivered to
the lungs through an endotrachea tube. Paramedics
would then administer chest compressions, which would
force blood through the cold lungs. From there, the
chilled blood would pass through the carotid arteries
and into the brain, cooling it rapidly.

For several decades, doctors have recognized the
benefits of protective cooling for certain classes of
patients. In the past, however, doctors relied on
external cooling approaches - ice baths and cooling
jackets, for example -- to induce protective
hypothermia. These techniques lacked two of the
advantages of the ice slurry.

Most importantly, external cooling acts much more
slowly, greatly hampering its effectiveness. While the
ice slurry can cool the core of an organ by nearly
five degrees Celsius in only five minutes, external
cooling can take more than two hours to have the same
effect. In addition, doctors can target individual
organs by delivering the slurry internally, which
reduces the risk of secondary adverse effects
including shivering and possible arrhythmia, according
to Argonne engineer Ken Kasza.

"Current medical guidance says that if you want to
save the brain, you have to lower its temperature by
four or five degrees Celsius within five to 10 minutes
of cardiac arrest if paramedics can't restart the
heart," said Kasza, who led the development of the
slurry production and delivery technology. "For the
first time, we have a means of attaining the necessary
temperature in that short span of time."

Kasza originally started to develop ice slurries for
industrial cooling, where they would be pumped through
pipes ranging in size from six to 60 inches in
diameter. Under a joint Argonne-University of Chicago
Emergency Resuscitation Center collaboration funded by
a National Institutes of Health grant, Kasza further
developed the slurries for cooling and protecting
cardiac arrest victims.

More recently, Kasza and his Argonne colleagues Yue
Wu, Chuck Vulyak , Adrian Tentner and Paul Fischer
have teamed up with surgeons at the University of
Chicago under BIASE, to further develop and
demonstrate the use of ice slurries for protective
cooling during several types of surgery. The three
surgical applications for ice slurry cooling focus on
minimally invasive laparoscopic kidney surgery,
cardiovascular surgery and surgeries that would
otherwise risk neurological damage to the brain and
spine.

According to Kasza, minimally invasive laparoscopic
kidney surgery represents the "lowest-hanging fruit"
for initiating clinical trials of protective ice
slurry cooling. Because this type of operation almost
completely cuts off the blood flow to the kidney,
rapid cooling could give doctors the precious extra
time they need to perform the operation without
risking damage.

Kasza and University of Chicago surgeon Arieh Shalhav
have already explored the use of ice slurry cooling in
kidney surgeries on large animals with promising
results, and they plan to seek FDA approval for human
trials. In the near future, Kasza hopes to find a
biomedical company interested in commercializing the
slurry production and delivery equipment technology.
"Ideally, we want to entice the private sector to
invest in this life-saving technology," he said.

If researchers can prove that the slurry can protect
an array of organs during a variety of surgical
procedures, they might eventually be able to use it to
stabilize soldiers who sustain severe injuries on the
battlefield. Since troops in battle lack access to
immediate and sophisticated medical care, these
casualties have heretofore been almost universally
fatal. However, Kasza said, many medical researchers
believe that by chilling the body's core to just a few
degrees above freezing, doctors can keep patients in
temporary stasis until they can receive the necessary
medical intervention.

In order to more efficiently and safely introduce the
slurry into a patient's body for a given application,
Kasza, Tentner and Fischer have begun to use
three-dimensional models and computer simulation to
analyze the thermal interaction between slurry and
tissue. These models give scientists the ability to
simulate and visualize the heat exchange and blood
flow within target organs and calculate how quickly
and uniformly they are cooled to protective levels.

The researchers also plan to develop simulations of
the entire circulatory system in order to quantify the
cooling effect of the slurry on major organs that are
not the direct target of the surgical procedure but
that may still require protective cooling during
surgery. The computer simulations ultimately will also
give surgeons the ability to tailor protective cooling
treatments to the needs of individual patients, Kasza
said.

"In the emergency and surgical situations that we're
dealing with, time frequently is the most valuable
resource we have," Kasza said. "By understanding the
complex interactions between the slurry and the
vulnerable organs, we can optimally induce protective
cooling and save lives." 

Argonne National Laboratory seeks solutions to
pressing national problems in science and technology.
The nation's first national laboratory, Argonne
conducts leading-edge basic and applied scientific
research in virtually every scientific discipline.
Argonne researchers work closely with researchers from
hundreds of companies, universities, and federal,
state and municipal agencies to help them solve their
specific problems, advance America 's scientific
leadership and prepare the nation for a better future.
With employees from more than 60 nations, Argonne is
managed by UChicago Argonne, LLC for the U.S.
Department of Energy's Office of Science.

By Jared Sagoff 

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