In Dr. Vukov’s talk about brain death, he first distinguished between disorders of consciousness, such as locked-in state or minimally conscious state, and a vegetative state. I thought it was really interesting that the technique to determine whether or not someone is in a vegetative state is by asking something such as, “Can you imagine playing tennis with me?” and using brain scans to determine whether the brain was actively doing so. This is a quick diagnosis, but the caveat is that doctors must catch the patient while they’re awake in order to ask them, which can be difficult. Brain death is very different from disorders of consciousness and is synonymous with death, particularly in the US. Not only does someone need to be in an irreversible coma to be pronounced brain dead, but they must meet two more requirements: complete absence of brain stem function and absence of spontaneous respiration.
It first became very important to define death following the development of the first ventilator in the 1930s and then the first successful organ transplant in 1967 because it opened up the possibility of acting quickly to preserve the organs of donors who were just pronounced dead. Also, cardiac death and brain death could now be separate; however, without a ventilator one would follow the other. In the United States, death is pronounced if either the Cardiopulmonary Standard or the Neurological Standard is met. A problem with the Cardiopulmonary Standard is that we currently cannot determine when someone’s cardiopulmonary systems have stopped. Being “close enough” is no longer acceptable in a world where there is the possibility of organ transplantation. A problem with the Neurological Standard is that although most organs are harvested from neurologically dead individuals, certain individuals who meet the criteria for brain death raise questions about whether or not this criterion actually captures death (for example, Johi McMath). These problems raise ethical issues because doctors want to continue transplanting organs, but doctors do not want to prematurely pronounce someone brain dead solely for their organs. Also, it is important for healthcare officials to respect patients’ and families’ wishes at the end of life, but it’s unreasonable to waste resources, especially on someone who is already dead.
In “When is dead really dead?” by Katharina Busl, a neurologist specializing in neurocritical care, Dr. Busl agrees with Dr. Vukov that up until the 1930s when ventilators were created and the 1950s when pacemakers were developed, “death” was simply defined when the heart stopped beating and breathing ceased, and death is much trickier to define today. However, there is not a machine that could revive a patient with irreversible brain damage, which introduced the concept of “brain death,” which has been legally adopted in the U.S. and many other parts of the world. She agrees with Dr. Vukov that brain death is difficult to imagine and is a less visible form of death because the patient’s heart continues to beat (typically from machines) and the body is still warm to touch. However, on April 17, 2019, Nature published a study that has made brain death an even more controversial topic. The study examined pig brains in which the scientists took the brains of pigs that had been slaughtered and “connected them to a machine that pumped an artificial blood-like nutritional fluid through the brains” for four hours after the slaughtering and measured brain cell activity. The scientists discovered that even four hours after death, blood circulation and certain brain cell functions could be restored. This research suggests that our brains may have “a better capacity to heal than is currently know.” However, Dr. Busl believes that although this is scientific news because it is an experiment that has never been done before, scientists have known for a long time that death is a continuum so it is not groundbreaking. Dr. Busl believes this research does not demonstrate that these brain cells that were able to function after death were a part of a cell network that lead to higher brain function that make humans distinct from other animals, such as consciousness and awareness. Also, the research does not show how these brains will function for a long period after restoration but rather an immediate restoration of some cell function. Hooking up patients to artificial blood and oxygen supplies could maintain living body parts or cells, but like Dr. Vukrov discussed, it is unethical to waste resources on doing so when the person will remain in an irreversible coma. Dr. Vukrov believes that it may be best to stop worrying about giving a black and white definition of death in terms of brain death because scientists still do not really know the difference between death and brain death.
An angiogram of a brain with blood flow (left) and without blood flow (right), as would be examined in a brain dead patient.
Works Cited:
Busl, Katharina. “When Is Dead Really Dead?” EarthSky, 28 Apr. 2019, earthsky.org/human-world/study-death-pig-brains-activity-4-hours-later.
Picture Works Cited:
“Understanding Brain Death.” Finger Lakes Donor Recovery Network, www.donorrecovery.org/learn/understanding-brain-death/.
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