In 1968 the "Harvard criteria" for determining brain death were published in the Journal of the American Medical Association, under the title of "A Definition of Irreversible Coma." This article was published without substantiating data, either from scientific research or from case studies of individual patients. For this reason, a majority of the presenters at the conference in Rome stated that the "Harvard criteria" were scientifically invalid.
In 2002 the results of a worldwide survey were published in Neurology, concluding that the use of the term "brain death" worldwide is "an accepted fact but there was no global consensus on the diagnostic criteria" and there are still "unresolved issues worldwide."
As he put it: Scrutinizing the existence of the symptoms of death as perceived by common sense, science no longer presupposes the "normal" understanding of life and death. It in fact invalidates normal human perception by declaring human beings dead who are still perceived as living.
The new approach to defining death, the German scholar continued, reflected a different set of priorities:
It was no longer the interest of the dying to avoid being declared dead prematurely, but other people’s interest in declaring a dying person dead as soon as possible.
Two reasons are given for this third party interest:
guaranteeing legal immunity for discontinuing life-prolonging measures that would constitute a financial and personal burden for family members and society alike, and collecting vital organs for the purpose of saving the lives of other human beings through transplantation. These two interests are not the patient’s interests, since they aim at eliminating him as a subject of his own interests as soon as possible.
The arguments against the use of "brain death" as a determination of death are being made, Spaemann noted, "not only by philosophers, and, especially in my country, by leading jurists, but also by medical scientists." He quoted the words of a German anesthesiologist who wrote, "Brain-dead people are not dead, but dying."
Dr. Paul Byrne, a neonatologist from Toledo, Ohio, offered a medical perspective - he testified:When organs are removed from a "brain dead" donor, all the vital signs of the "donors" are still present prior to the harvesting of organs, such as: normal body temperature and blood pressure; the heart is beating; vital organs, like the liver and kidneys, are functioning; and the donor is breathing with the help of a ventilator.
Defending the criteria
Some participants in the February meeting defended the use of the "brain death" criteria. Dr. Stewart Youngner of Case Western University in Ohio admitted that "brain dead" donors are alive, but argued that this should not prove an impediment to the harvesting of their organs. His reasoning was that there is such poor "quality of life" in the "brain dead" patient that it would be more beneficial to harvest their organs to extend the life of another than to continue the life of the organ donor.
Dr. Conrado Estol, a neurologist from Buenos Aires, explained the steps that should be followed in determining the "brain death" of a prospective organ donor. Dr. Estol, who is strongly in favor of harvesting human organs to extend the life of other patients, presented a dramatic video of a person diagnosed as "brain dead" who attempted to sit up and cross his arms, although Dr. Estol assured the audience that the donor was a cadaver. This produced an unsettling response among many participants at the conference.
The apnea test
In his presentation at the conference, Dr. Cicero Coimbra, a clinical neurologist from the Federal University of Sao Paolo, Brazil denounced the cruelty of the apnea test, in which mechanical respiratory support is withdrawn from the patient for up to 10 minutes, to determine whether he will begin breathing independently. This is part of the procedure before declaring a brain-injured patient "brain dead." Dr. Coimbra explained that this test significantly impairs the possible recovery of a brain-injured patient, and can even cause the death of the patients.
He argued:A large number of brain-injured patients, even in deep coma, can recover to lead a normal daily life; their nervous tissue may be only silent, not irreversibly damaged, as a consequence of a partial reduction of the blood supply to the brain. (This phenomenon, called "ischemic penumbra," was not known when the first neurological criteria for brain death were established 37 years ago.) However, the apnea test (considered the most important step for the diagnosis of "brain death" or brain-stem death) may induce irreversible intra-cranial circulatory collapse or even cardiac arrest, thereby preventing neurological recovery.
During the apnea test, the patients are prevented from expelling carbon dioxide (CO2), which becomes a poison to the heart as the blood CO2 concentration rises.
As a consequence of this procedure, the blood pressure drops, and the blood supply to the brain irreversibly ceases, thereby causing rather than diagnosing irreversible brain damage; by reducing the blood pressure, the "test" further reduces the blood supply to the respiratory centers in the brain, thereby preventing the patient from breathing during this procedure. (By breathing, the patient would demonstrate that he is alive.)
Irreversible cardiac arrest (death), cardiac arrhythmias, myocardial infarction, and other life-threatening detrimental effects may also occur during the apnea test. Therefore, irreversible brain damage may occur during and before the end of the diagnostic procedures for “brain death.”
Dr. Coimbra concluded by saying that the apnea test should be considered unethical and declared illegal as an inhumane medical procedure. If family members were informed of the brutality and risk of the procedure, he stated, most of them would deny permission. He pointed out that when a heart attack patient is admitted to the emergency room he is never subjected to a stress test in order to verify that he is suffering from heart failure. Instead the patient is given special care and protection from further stress to the heart.
In contrast when a brain-injured patient is subjected to the apnea test, further stress is placed on the organ that has already been injured, and additional damage can endanger the patient’s life. Dr. Yoshio Watanabe a cardiologist from Nagoya, Japan, concurred, saying that if patients were not subjected to the apnea test, they could have a 60 percent chance of recovery to normal life if treated with timely therapeutic hypothermia.
The question of a brain-injured patient's possible recovery also concerned Dr. David Hill, a British anesthetist and lecturer at Cambridge. He observed: "It should be emphasized first that it was widely admitted, that some functions, or at least some activity, in the brain may still persist; and second that the only purpose served by declaring a patient to be dead rather than dying, is to obtain viable organs for transplantation." The use of these criteria, he concluded, "could in no way be interpreted as a benefit to the dying patient, but only (contrary to Hippocratic principles) a potential benefit to the recipient of that patient’s organs."
Dr. Hill recalled that the earliest attempts at transplanting vital organs often failed because the organs, taken from cadavers, did not recover from the period of ischemia following the donor's death. The adoption of brain-death criteria solved that problem, he reported, "by allowing the removal of vital organs before life support was turned off - without the legal consequences that might otherwise have attended the practice."
While it is remarkable that the public has accepted these new criteria, Dr. Hill remarked, he attributed that acceptance in large part to the favorable publicity for organ transplants, and in part to public ignorance about the procedures. "It is not generally realized," he said, "that life support is not withdrawn before organs are taken; nor that some form of anaesthesia is needed to control the donor whilst the operation is performed." As knowledge of the procedure increases, he observed, it is not surprising that - as reported in a 2004 British study - "the refusal rate by relatives for organ removal has risen from 30 percent in 1992 to 44 percent." Dr. Hill also suggested that when relatives see with their own eyes the evidence that a potential organ donor is still alive, they harbor enough doubts so that they are not ready to consent to the organ removal.
In the United Kingdom, Dr. Hill reported, there is mounting pressure for individuals to sign, and always carry with them, donor cards authorizing doctors to use their vital organs. Today only about 19 percent of the country's people have registered as organ donors, but vehicle-registration forms, driver's-license applications, and other public documents provide "tick boxes" allowing citizens to give this advance directive; even children are encouraged to sign. All such documents specify that organs may be harvested only "after my death," but there is no definition of what constitutes "death."
Again, Dr. Hill remarked, the acceptance of transplants hangs on the public's lack of understanding about the procedure. And yet, he pointed out, "For any other procedure, informed consent is required, but for this most final of operations no explanation nor counter-signature is required, nor is the opportunity given to discuss the question of anaesthesia."
The Signs of Death
Many in the medical and scientific community maintain that brain-related criteria for death are sufficient to generate moral certitude of death itself. Ongoing medical and scientific evidence contradicts this assumption. Neurological criteria alone are not sufficient to generate moral certitude of death itself, and are absolutely incapable of generating physical certainty that death has occurred.
It is now patently evident that there is no single socalled neurological criterion commonly held by the international scientific community to determine certain death. Rather, many different sets of neurological criteria are used without global consensus.
Neurological criteria are not sufficient for declaration of death when an intact cardio-respiratory system is functioning. These neurological criteria test for the absence of some specific brain reflexes. Functions of the brain not considered are temperature control, blood pressure, cardiac rate and salt and water balance. When a patient on a ventilation machine is declared "brain dead," these functions not only are present but also are frequently active.
The apnea test - the removal of respiratory support - is mandated as a part of the neurological diagnosis and it is paradoxically applied to ensure irreversibility. This significantly impairs outcome, or even causes death, in patients with severe brain injury.
There is overwhelming medical and scientific evidence that the complete and irreversible cessation of all brain activity (in the cerebrum, cerebellum and brain stem) is not proof of death. The complete cessation of brain activity cannot be adequately assessed. Irreversibility is a prognosis, not a medically observable fact. We now successfully treat many patients who in the recent past were considered hopeless.
Monday, July 16, 2007
On "brain death"
KAO is an organization of parents who found out what happens to "brain dead" transplant donors only after they had signed consent for their children's organs to be harvested. Below are some excerpts from their web site.