January 13, 2014

Unconscious Biases

“Ariel Sharon dies after 8 years in a coma,” proclaimed one headline. “Brain dead pregnant woman kept alive” said another. Neither headline can possibly be accurate. The former prime minister of Israel was not in a coma. The pregnant woman in Texas is either not brain dead or, if she is dead, no medical technology can “keep her alive.” From simple fainting to death, with coma, vegetative state, minimally conscious state, and persistent vegetative state in between, unconsciousness is a messy business. But it’s time we—the general public, the media, lawyers—got it straight. The distinctions matter.

Once upon a time, if your heart stopped beating and you weren’t breathing, you were dead. Anyone could identify a dead body. But  then modern medical science made a few radical discoveries. Medicine showed that some people who looked like they were dead were actually in a kind of state of suspended animation. It turned out that if your heart and your breathing stopped because of profound cold (hypothermia) or certain drugs, you had a decent chance of waking up if you were re-warmed or if the drugs were removed from your system. Medical science led to new technologies such as ventilators that take over for the lungs and pacemakers that stimulate the heart to pump. Dependence on the new technologies was not the same as death. All these developments challenged the traditional notion of death. And then in 1968, a new concept of brain death was born. Articulated by a Harvard Ad Hoc committee, the new way of looking at death emergend from the recognition that the brain is our central processing unit, the organ that organizes and integrates all the functions necessary for human life.

It’s perhaps unfortunate that brain death was originally defined by a committee. It’s regrettable that it was an ad hoc committee and one with the name of a single university attached. But the basic view of this group, that death exists when the entire brain irreversibly ceases to function, has become established as the legally recognized definition of death in all 50 states and the District of Columbia. The American Academy of Neurology has issued guidelines detailing how, in practice, brain death should be determined. Any neurologist, neurosurgeon, or intensive care unit specialist should be able to make the assessment. And it doesn’t require any fancy technology: diagnosing death is basically a clinical determination, though in hospitals today, physicians often use tests such as EEGs or MRIs as “confirmatory evidence.” A person is dead if his brain is dead.

Since the introduction of the modern concept of brain death less than 50 years ago, physicians have learned a great deal about the various forms of unconsciousnessThere’s fainting or “passing out,” characterized by transient loss of blood flow to the brain, a reversible condition that is familiar to most people and which can be brought about by marked anxiety or by extremely low blood pressure. Then there’s coma, in which a person is in a deeper state of unconsciousness and doesn’t respond at all to his environment. The eyes are closed. Coma results from conditions such as trauma or stroke and typically lasts no more than a few weeks. People in coma either wake up or move into a vegetative state. 

A vegetative state is much like coma except the eyes are open and it can last much longer. The person looks as though he is awake, but he’s not. His eyes wander randomly; he does not respond to words or to physical stimuli. Someone in a vegetative state often has a working brainstem, the part of the brain responsible for automatic functions such as breathing. But he has no cognitive function—no awareness, no ability to think or hear or speak. 

From a vegetative state, a person can progress to either a minimally conscious state or a persistent vegetative state. The minimally conscious state is a recently described state in which a person has a very limited amount of higher level brain function: sophisticated tests such as a functional MRI show some kind of neurological response when the person is shown familiar photographs or words. The persistent vegetative state—the other possible next step after a vegetative state—is basically the same as a vegetative state but one that has lasted a long time (months) and is now irreversible.

It should be evident from even this brief description of the varieties of unconsciousness that Ariel Sharon was not in a coma for eight years. Exactly what state he was in is not entirely clear from the public record, but it was most likely PVS. He was sustained by artificial nutrition and hydration. Acute illnesses such as infection were treated with antibiotics. Apparently his death was precipitated by kidney failure: his kidneys shut down and the decision was made not to start dialysis but rather to allow him to die. Whether Marisa Munoz is brain dead or is in a vegetative state is also not clear from the public record. If she’s in a vegetative state then, according to Texas law, medical interventions to sustain her and allow her pregnancy to continue are required, even if she would not have wanted such interventions. If she is brain dead, then she is dead, period. There is no such thing as “life sustaining treatment” for a dead person. We cannot revive the dead. And the state cannot decide to use a dead body as an incubator for a fetus, any more than it can decide to remove organs from a dead body to save the lives of people awaiting transplants.

These in-between states are hard to accept because the people languishing in such a condition—and there are somewhere between 15,000 and 40,000 people in the US in a PVS—do not look dead. They are not cold. Their hearts are beating. Their eyes are open. Common sense tells us they must be alive. But science is often at odds with common sense. Common sense rejected the notion that micro-organisms (tiny single celled organisms that are invisible to the naked eyes) could cause disease. Common sense dismissed the connection between cigarettes and cancer. Common sense holds that pneumonia results from going out into the cold without a hat and that cancer results from repressing emotions. The essence of the science is that it reveals truths that are not self-evident.

Difficult as the distinctions among the different states of unconsciousness may be to accept—and it hasn’t helped that the terminology has evolved over time—we have to get them right. Only then will we be able to spell out in an advance directive how we wish to be treated if we are ever in one of these conditions or to tell our families and physicians. Only then will we be able to make a decision based on our moral understanding, not on magical thinking that allows us to believe that an irreversible condition can be “cured.” People may disagree about the morally correct way to treat someone who is in limbo between life and death. The Catholic Church holds that reverence for the sanctity of life requires that people in PVS be treated with artificial nutrition and hydration. 

I think that the best way to show respect for human life is not to confuse it with a mere collection of cells, cells that do not and will never be able to function as a thinking, feeling human being. Accordingly, I think that it is wrong to inflict invasive medical treatment on someone in a persistent vegetative state. I have written a living will in the form of a letter to my husband, my formally designated health care proxy, telling him what approach to medical care I would want if I lost the functions that make me who I am. I encourage everyone to learn about unconsciousness states, to think about what their goals would be for themselves if they developed such a condition, and to share their views with the person who would make decisions for them if they lost the ability to make their own decisions. 

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