[ES-ALS-Providers] To Treat The Dead

[Fritz Lauer]

Hello all,

 

Here's an article that I read over the weekend on MSN and thought I'd share
it with all of you.

 

Stay safe,

Fritz

 

To Treat the Dead
 
The new science of resuscitation is changing the way doctors 
think about heart attacks-and death itself.
 
Ed Kashi / Corbis
Emergency: The goal is to give victims more time
   
 
By Jerry Adler
Newsweek
May 7, 2007 issue - Consider someone who has just died of a 
heart attack. His organs are intact, he hasn't lost blood. 
All that's happened is his heart has stopped beating-the 
definition of "clinical death"-and his brain has shut down 
to conserve oxygen. But what has actually died?
 
As recently as 1993, when Dr. Sherwin Nuland wrote the best 
seller "How We Die," the conventional answer was that it was 
his cells that had died. The patient couldn't be revived 
because the tissues of his brain and heart had suffered 
irreversible damage from lack of oxygen. This process was 
understood to begin after just four or five minutes. If the 
patient doesn't receive cardiopulmonary resuscitation within 
that time, and if his heart can't be restarted soon 
thereafter, he is unlikely to recover. That dogma went 
unquestioned until researchers actually looked at oxygen-
starved heart cells under a microscope. What they saw amazed 
them, according to Dr. Lance Becker, an authority on 
emergency medicine at the University of Pennsylvania. "After 
one hour," he says, "we couldn't see evidence the cells had 
died. We thought we'd done something wrong." In fact, cells 
cut off from their blood supply died only hours later.
But if the cells are still alive, why can't doctors revive 
someone who has been dead for an hour? Because once the 
cells have been without oxygen for more than five minutes, 
they die when their oxygen supply is resumed. It was 
that "astounding" discovery, Becker says, that led him to 
his post as the director of Penn's Center for Resuscitation 
Science, a newly created research institute operating on one 
of medicine's newest frontiers: treating the dead.
 
Biologists are still grappling with the implications of this 
new view of cell death-not passive extinguishment, like a 
candle flickering out when you cover it with a glass, but an 
active biochemical event triggered by "reperfusion," the 
resumption of oxygen supply. The research takes them deep 
into the machinery of the cell, to the tiny membrane-
enclosed structures known as mitochondria where cellular 
fuel is oxidized to provide energy. Mitochondria control the 
process known as apoptosis, the programmed death of abnormal 
cells that is the body's primary defense against cancer. "It 
looks to us," says Becker, "as if the cellular surveillance 
mechanism cannot tell the difference between a cancer cell 
and a cell being reperfused with oxygen. Something throws 
the switch that makes the cell die."
 
With this realization came another: that standard emergency-
room procedure has it exactly backward. When someone 
collapses on the street of cardiac arrest, if he's lucky he 
will receive immediate CPR, maintaining circulation until he 
can be revived in the hospital. But the rest will have gone 
10 or 15 minutes or more without a heartbeat by the time 
they reach the emergency department. And then what 
happens? "We give them oxygen," Becker says. "We jolt the 
heart with the paddles, we pump in epinephrine to force it 
to beat, so it's taking up more oxygen." Blood-starved heart 
muscle is suddenly flooded with oxygen, precisely the 
situation that leads to cell death. Instead, Becker says, we 
should aim to reduce oxygen uptake, slow metabolism and 
adjust the blood chemistry for gradual and safe reperfusion.
 
Researchers are still working out how best to do this. A 
study at four hospitals, published last year by the 
University of California, showed a remarkable rate of 
success in treating sudden cardiac arrest with an approach 
that involved, among other things, a "cardioplegic" blood 
infusion to keep the heart in a state of suspended 
animation. Patients were put on a heart-lung bypass machine 
to maintain circulation to the brain until the heart could 
be safely restarted. The study involved just 34 patients, 
but 80 percent of them were discharged from the hospital 
alive. In one study of traditional methods, the figure was 
about 15 percent.
 
Becker also endorses hypothermia-lowering body temperature 
from 37 to 33 degrees Celsius-which appears to slow the 
chemical reactions touched off by reperfusion. He has 
developed an injectable slurry of salt and ice to cool the 
blood quickly that he hopes to make part of the standard 
emergency-response kit. "In an emergency department, you 
work like mad for half an hour on someone whose heart 
stopped, and finally someone says, 'I don't think we're 
going to get this guy back,' and then you just stop," Becker 
says. The body on the cart is dead, but its trillions of 
cells are all still alive. Becker wants to resolve that 
paradox in favor of life. 

 

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