skywizard
20th June 2014, 01:55
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Sometimes, the line between life and death can seem blurred. In one recent case, a woman was erroneously declared
dead after having a heart attack and wound up freezing to death in a body bag in the morgue. Another woman gave
birth to a baby three months after she technically died. Then, there was a case of a skier who became submerged under
freezing water for hours, but was revived and suffered no brain damage.
These and other cases reveal how hard it can be to distinguish the living from the dead. With the advent of mechanical ventilators, the clear-cut definition of death has now given way to other, more clinical definitions.
But these terms, such as "brain death" and "circulatory death," can create ambiguity about who is dead and who isn't, experts say.
What is death?
Despite its frequent use, the term "clinical death" doesn't actually have a consistent meaning, said Dr. James Bernat, a neurologist at Dartmouth College's Geisel School of Medicine in New Hampshire. In most hospitals, the doctor in charge of a patient's care makes the death determination, and there aren't universal guidelines for when to make that call, he said.
"You're dead when a doctor says you're dead," Bernat told Live Science.
Until the 1950s, death was considered to be the point when any one of the vital functions — heartbeat, electrical brain activity or respiration — ceased. Once one part of the system failed, then the others would soon shut down as well, the reasoning went.
But the advent of the mechanical ventilator, which pushes air into and out of the lungs, created a new category called brain death, Bernat said.
That led to a whole class of people with warm bodies and circulating blood — who could even fight off infections or gestate a baby — but who had absolutely no brain function, said Leslie Whetstine, a philosopher at Walsh University in Ohio who studies the definitions of death.
To be declared brain-dead, a person must have irreversibly lost function in all parts of his or her brain. Doctors make that call by performing neurological exams to search for electrical brain activity, or blood circulation to the brain, as well as a test to see if the patient attempts to breathe when the ventilator is turned off.
Strides in organ transplantation also drove the push for this new category of death.
"The person who was diagnosed as brain-dead was an ideal multiple organ donor," because all of their organs were supplied with oxygen and, therefore, were not damaged, Bernat said.
Read Full Story: http://www.livescience.com/46418-clinical-death-definitions.html
peace...
Sometimes, the line between life and death can seem blurred. In one recent case, a woman was erroneously declared
dead after having a heart attack and wound up freezing to death in a body bag in the morgue. Another woman gave
birth to a baby three months after she technically died. Then, there was a case of a skier who became submerged under
freezing water for hours, but was revived and suffered no brain damage.
These and other cases reveal how hard it can be to distinguish the living from the dead. With the advent of mechanical ventilators, the clear-cut definition of death has now given way to other, more clinical definitions.
But these terms, such as "brain death" and "circulatory death," can create ambiguity about who is dead and who isn't, experts say.
What is death?
Despite its frequent use, the term "clinical death" doesn't actually have a consistent meaning, said Dr. James Bernat, a neurologist at Dartmouth College's Geisel School of Medicine in New Hampshire. In most hospitals, the doctor in charge of a patient's care makes the death determination, and there aren't universal guidelines for when to make that call, he said.
"You're dead when a doctor says you're dead," Bernat told Live Science.
Until the 1950s, death was considered to be the point when any one of the vital functions — heartbeat, electrical brain activity or respiration — ceased. Once one part of the system failed, then the others would soon shut down as well, the reasoning went.
But the advent of the mechanical ventilator, which pushes air into and out of the lungs, created a new category called brain death, Bernat said.
That led to a whole class of people with warm bodies and circulating blood — who could even fight off infections or gestate a baby — but who had absolutely no brain function, said Leslie Whetstine, a philosopher at Walsh University in Ohio who studies the definitions of death.
To be declared brain-dead, a person must have irreversibly lost function in all parts of his or her brain. Doctors make that call by performing neurological exams to search for electrical brain activity, or blood circulation to the brain, as well as a test to see if the patient attempts to breathe when the ventilator is turned off.
Strides in organ transplantation also drove the push for this new category of death.
"The person who was diagnosed as brain-dead was an ideal multiple organ donor," because all of their organs were supplied with oxygen and, therefore, were not damaged, Bernat said.
Read Full Story: http://www.livescience.com/46418-clinical-death-definitions.html
peace...