Suspended Animation? Docs Try Stopping Clock to Save Lives
By Linda Carroll, NBC News
It sounds like the stuff of science
fiction: a mortally injured patient is put into suspended animation so
doctors can buy time to close up his wounds and save his life.
that seemingly improbable scenario is about to become a reality at five
centers around the United States where doctors will try to stop the
clock on patients who've sustained gunshot or knife wounds that were so
severe their hearts stopped.
In the past, when
efforts to restart the heart failed because so much blood had been lost,
these patients would have been declared dead because there was no way
to get enough oxygen to the brain before it was irreparably damaged.
now think that by quickly and dramatically cooling down a trauma
patient by replacing blood with cold saline solution, they can send all
the cells of the body into slow motion. That would mean the cells would
need less oxygen, which would give doctors the time needed to make
repairs that would stop the bleeding.
Normally, the brain would be damaged after five minutes of oxygen
deprivation. But researchers suspect that by slowing cell metabolism
with cold, they can stretch that five minutes to an hour or more.
Research in pigs suggests "that if
we could cool a person fast enough and cold enough, we could then
basically stop the clock, and that would buy time for the surgeon to get
control over the bleeding," said Dr. Sam Tisherman, a professor of
critical care medicine and surgery at UPMC where trials of the technique
are about to begin. "If we could get the bleeding under control, that
would be a huge change for us."
Once repairs are made,
blood would be exchanged for the saline solution through a heart-lung
bypass machine. This would restore circulation and bring body
temperature back up to normal. In animal models, the effect has been
fascinating," said Dr. Paul Vespa, a professor of neurology and
neurosurgery and director of critical care at the University of
California, Los Angeles. "They have basically suspended animation and in
an animal model, there's an amazing recovery."
who is not involved in the study, has seen an animal go from cold and
"dead" to up and walking as if nothing had happened.
UPMC, they're just waiting for the right patient — one with cardiac
arrest due to penetrating wounds and significant blood loss — to be
wheeled into the emergency room. All the paper work is done; the team is
is trained and ready.
inspiration for the research initially came from anecdotal reports of
people surviving without damage even after spending an hour or more
underwater without breathing. The common thread in all of those
miraculous survival stories was that they occurred in water that was
"That made people think
that even if our heart stopped, if you could get cold fast enough, the
brain, heart and other organs might be OK," Tisherman said.
Surgeons are already using the principle to operate on babies born with congenital heart defects, Tisherman said.
discovery that animals — and maybe humans — could be put into a state
of suspended animation is causing scientists to redefine what "dead"
means, said Dr. Peter Rhee, a professor of surgery and chief of trauma,
critical care, burns and emergency surgery at the University of Arizona.
When in this state, a patient would be neither dead nor alive, he
Rhee has been working
on suspended animation for nearly 20 years. His experiments have shown
that animals could be brought back from a suspended state undamaged,
"even though they were by all clinical measures dead."
you stop the machinery of life, that's not when death starts," Rhee
said. "If you were dead for a day I would not be able to bring you back.
But we're talking about 5 to 15 minutes. If you're cooled straight
down, you have a chance."
One issue that slowed the research
in humans was the impossibility of getting consent from an individual
who is wheeled into the emergency room dead, for all intents and
purposes. Ultimately, the way around the problem was to consent an
entire community by putting word out through the media that the new
technique would be tried if there was no other option.
suspects that if the trials show promising results, it will also change
the way patients are treated on the way to the hospital.
"You may one day see ambulances come out and EMTs immediately start cooling the patient. Time is brain," Vespa said.
know that you lose two million brain cells every minute of a stroke, he
added. So, "if you could completely stop the injury process you're
going to save a lot of brain cells."
the current state of the art suggests that you can have just a couple
of hours of suspended animation, Rhee thinks the research is just at its
"A couple of hundred
years ago people thought you couldn't fly through the air," he said.
"Gliding was the beginning. These are just baby steps, this idea of
putting a person in a state where they are not really alive or dead. How
long can that period be? We don't know. We are now asking the questions
that might give us the answer to that."