In 1968, the "Harvard criteria" for determining brain death were published in the Journal of the American Medical Association, under the title "A Definition of Irreversible Coma." The article was published without substantiating data. A conference was held in Rome reviewing the "Harvard criteria" and finding the criteria scientifically invalid.
From the KOA site:
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University of Sao Paolo, Brazil denounced the cruelty of the apnea test, in which mechanical respiratory support is withdrawn from the patient for up to 10 minutes, to determine whether he will begin breathing independently.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.
See also: Just how dead does an organ donor have to be?
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