Politics

Is Terri Schiavo Minimally Conscious?

And does it matter?

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The sad case of Terri Schiavo is roiling the nation. Should nutrition and hydration be withdrawn from the severely brain damaged woman or not?

First, let's clarify what the case is not. Terri Schiavo is not legally brain dead. In the United States brain death means whole brain death, including the death of the brain stem, which controls respiration and circulation. The definition of brain death was codified in 1980 in the Uniform Determination of Death Act, which has been adopted by most states. The UDDA noted that the "concept of 'entire brain' distinguishes determination of death under this Act from 'neocortical death' or 'persistent vegetative state.'" A brain-dead patient will show virtually no electrical activity in any part of his or her brain. The concept of brain death was developed because advances in medical technology allowed physicians to maintain the respiration and circulation in patients who previously would have died from damage to their brains.

Philosopher Robert Veatch thinks that whole brain death is too restrictive. He wants to define death as the death of neocortical functions in the brain. The neocortex is the wrinkled outer layer of the brain which is thought to be responsible for higher level cognitive functions, such as language, learning, memory, and complex thought. Veatch argues that a person should be declared dead when there is the "irreversible cessation of the capacity for consciousness." This concept, however, has been rejected by all official bodies anywhere in the world. There is something disturbing about declaring someone dead if they can still open and close their eyes. Yet Veatch makes a strong case that while the body of such a patient might still breathe and digest, the person is lost to us. But how to determine whether the capacity of consciousness has irreversibly ceased?

Is that the case for people diagnosed as being in a persistent vegetative state? The concept of persistent vegetative state was first devised by neurologists Bryan Jennett and Fred Plum in 1972. They were distinguishing PVS from coma. When a patient is in a coma, his or her eyes are closed and they do not respond to any stimuli.

Patients in PVS follow the sleep wake cycle and do open their eyes. But patients in PVS show complete unawareness of the self and the environment, and they exhibit no evidence of sustained, reproducible, purposeful, or voluntary behavioral responses to visual, auditory, tactile, or noxious stimuli and no evidence of language comprehension or expression. PVS generally results from traumatic brain injuries or metabolic imbalances.

In this case, Schiavo's brain was severely damaged when her heart stopped for 14 minutes, cutting the oxygen supply to her brain. Court appointed neurologists have determined that Schiavo is in a persistent vegetative state while other neurologists solicited by her parents reject that diagnosis and suggest that she in minimally conscious. Many of the neurologists solicited by her parents have apparently made their diagnoses on the basis of short edited video clips.

Is there a way to resolve these diagnostic differences? To tell if Terri Schiavo is still with us? Whether or not her capacities for consciousness have ceased? So far no one has invented a consciousness detector. However, a recent study using magnetic resonance imaging (MRI) on patients who have been diagnosed as being minimally conscious (MCS) have made some suggestive findings with regard to the amount of activity occurring in their damaged brains.

In their study, neurologists compared the brain activity of two severely brain damaged patients who had been diagnosed as being minimally conscious with the brain activity of normal subjects. Brain scans showed that the same areas in the brains of both normal subjects and the brain damaged patients were activated as recorded stories told by loved ones were played into headsets. The neurologists concluded, "These findings of active cortical networks that serve language functions suggest that some MCS patients may retain widely distributed cortical systems with potential for cognitive and sensory function despite their inability to follow simple instructions or communicate reliably." However, the MCS patients showed less than half the activity of normal subjects and their brains' language circuits went quiet when the tapes were played backwards whereas normal subjects increased their neural activity as they struggled to decode the backward playing tapes.

Let's say that Schiavo is reevaluated as her parents and Congress are demanding and she undergoes testing in an MRI machine. The MRI scan finds that she has some cortical response to language, that she is minimally conscious. Does that help us decide what the moral thing to do in her case is? Unfortunately, no. She still cannot communicate her wishes to us. Science will not help us here, unless patients can somehow send us signals via MRIs about what they want their medical treatment to be.

Compare MCS patients with patients suffering from locked-in syndrome. In locked in syndrome, patients are fully conscious but incapable any voluntary movement except their eyes. Locked-in syndrome is generally caused by damage to the brain stem, either by stroke or injury. Patients suffering from locked-in syndrome can communicate by using eye movements and blinks to let loved ones and caregivers know their wishes. The point is that severely brain damaged people who are conscious can legally and morally decide to forego hydration and nutrition if they choose.

The tragic truth is that it makes no difference whether Schiavo is PVS or minimally conscious; she can no longer tell her loved ones and her physicians what she would want her treatment to be. The U.S. Supreme Court decided in the 1990 case Cruzan vs. Director of the Missouri Department of Health that it was morally and legally acceptable to withhold hydration and nutrition from a PVS patient if there was "clear and convincing evidence" that the patient wished to refuse such treatment. Subsequently, the Missouri court found that Cruzan had told co-workers that she would never want to "live like a vegetable," and her feeding tube was removed.

Similarly, the court in Florida found that Schiavo had said that she would not want to be treated if there were no hope of recovery from a vegetative state. This is, of course, disputed, but courts make disputed findings of fact all the time. Unless we want to force every PVS patient who neglects to fill out a living will to accept a feeding tube, such court decisions are the best we can do in heartbreaking situations like this. The protection of human dignity requires that we discern and then honor as best we can the requests of those who can no longer communicate their desires to us.

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