Earlier this year, 13-year-old Trenton McKinley from Alabama
and his parents hit the media circuit to talk about the miracle of Trenton
awakening after being declared brain dead from a vehicle accident—1 day before
his organs were scheduled to be harvested.
The likely explanation for such "recoveries" from
brain death, according to experts, is that these individuals were never brain
dead in the first place. "Errors have been made where people declared
brain dead were later found to have spontaneous movement that should not have
been possible," says Robert M. Sade, MD, professor of surgery and director
of the Institute of Human Values in Health Care at the Medical University of
South Carolina in Charleston. "In virtually all those cases, brain-death
determination was not done correctly. If you don't go through the exact
protocol for brain-death determination, you're likely to have patients
diagnosed as being dead by neurologic criteria who are, in fact, not brain
dead."
A more typical brain death error is the 2011 case of a
55-year-old with brain injury who was treated with hypothermia to try to
optimize neurologic recovery. He was declared brain dead 24 hours after he was
rewarmed—which was too short a period of time. During preparation for organ
procurement, it was noticed that he had regained some brainstem reflexes—he
certainly wasn't fine—and, therefore, wasn't brain dead.
When the American Academy of Neurology (AAN) updated its
guidelines for determining brain death in adults in 2010, a committee of
experts searched the literature and found no legitimate "reports of
patients recovering brain function when the criteria for brain-death
determination was used appropriately," says Ariane K. Lewis, MD, associate
professor, department of neurology and neurosurgery, NYU Langone Medical
Center, New York City, and a member of the AAN's Ethics, Law, and Humanities
Committee.
But at the same time there is no way of knowing how many
people recover from brain death because they are usually quickly removed from
life support or become organ donors…
Subsequently, two neurologists stated that McMath was not
brain dead based on their interpretation of an EEG, an MRI, and an MRA done a
year later and observation of video clips from 2014 to 2016 that appeared to
show McMath following commands and communicating with finger movements.
"We have high confidence that McMath's initial
diagnosis of brain death was correct," says Thaddeus Mason Pope, JD, PhD,
director of the Health Law Institute and professor of law, Mitchell Hamline
School of Law in St Paul, Minnesota. "It's never happened in human history
that someone correctly diagnosed as brain dead is no longer dead."
To definitively prove that McMath had recovered sufficient
brain function to be considered alive, two physicians would have had to conduct
another formal determination of brain death to refute the initial one.
"If that were proven, that means that there is
something wrong with how we diagnose brain death, because it's supposed to be
an irreversible condition," Pope says. But that second evaluation was not
done and never will be because McMath died from liver failure in June 2018,
nearly 5 years after being declared brain dead.
James L. Bernat, MD, is one brain death expert who believes
the current neurologic tests leave too much room for error, and, consequently,
patients are being declared brain dead who aren't.
"There are a group of people who strongly believe that
although McMath fulfilled the pediatric brain death criteria, she wasn't really
brain dead because she retained certain brain functions," says Bernat,
active emeritus professor of neurology and medicine at Dartmouth Geisel School
of Medicine in Hanover, New Hampshire, and former chair of the AAN's Ethics,
Law, and Humanities Committee. "If she wasn't really brain dead, which I
believe to be the case, then it suggests that our tests are not fully accurate.
Some of us have argued in response to McMath and other cases that have been
published that we need to tighten up the tests to eliminate cases like this
getting through in the future."…
Sade, who previously ran South Carolina's organ procurement
program, stirs the brain death controversy in the opposite direction. He is
advocating for potential organ donors who are nearly dead to have their organs
harvested, which would make formal brain death determination unnecessary.
"Once a potential organ donor's death is imminent, I
would like for us to be able to remove his organs even though he is still
breathing, and his heart is beating," Sade says. Waiting until
brain-injured patients progress to brain death results in physiologic
abnormalities and organ damage from neurologic and hormonal changes, he says.
"Any organ donor would want the organs to be in the
best possible condition and as many organs used as possible for
transplantation." Sade estimates that as many as 6684 additional organs
could be retrieved from brain-injured organ donors who were imminently dead
rather than brain dead. "We could wipe out the waiting list for all organs
for two or three years," he says…
But ethicists have always found the UDDA to be problematic.
"The Uniform Determination of Death Act is a legal fiction because it
requires irreversible loss of function," Sade says. "There are some
patients who meet all the clinical criteria for brain death, and yet they still
have cells in their brain that are neurologically active. They can survive for
relatively long periods of time, although these cases are very infrequent.
Usually they die within a matter of days after they meet neurologic criteria
for brain death."…
Organ donors who are declared dead after circulation ceases
are also not irreversibly dead because they could have been resuscitated at the
time organ harvesting commences. "Someone is not irreversibly dead until
circulation stops for 10 to 20 minutes, but at that point, their organs are not
useable," Sade says.
https://www.medscape.com/viewarticle/902143_1
See: https://childnervoussystem.blogspot.com/2018/10/brain-death.html
https://childnervoussystem.blogspot.com/2018/05/premature-organ-donation.html
See: https://childnervoussystem.blogspot.com/2018/10/brain-death.html
https://childnervoussystem.blogspot.com/2018/05/premature-organ-donation.html
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