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Two new pieces were published on the subject of those who are PVS, Persistant Vegetative State.  These pieces discuss a new finding about how those who are PVS still show brain function.  It seems as though their brain waves are susceptible to suggestion, and show how the brain attempts to respond to the command even though the message never arrives at its destination within the body.  If this is so, then the discussion of withdrawal or withholding of treatment from someone in a PV state becomes more challenging.  As the article shows, if we are able to read brain waves based on communication, can we begin to determine the person’s needs through following brain activity?

New Hope for Detecting Consciousness in Vegetative Patients: Ethical ImplicationsHealth Care
Franklin G. Miller and Robert D. Truog 11/29/2011

New Hope for Detecting Consciousness in Vegetative Patients: Ethical Implications

Patients diagnosed as being in a persistent vegetative state have figured prominently in the law and medical ethics relating to end-of-life decisions since the case of Karen Quinlan in 1976. These patients have profound brain injuries that leave them in the seemingly anomalous condition of being awake but not aware. They have normal sleep-wake cycles and the capacity to breathe on their own, but lack clinical signs of consciousness. Recent scientific developments that suggest signs of willful modulation of mental activity have roiled the waters relating to the care of patients in a vegetative state.

On November 10 The Lancet published a report that showed that EEG detected brain activation in a proportion of patients considered to be permanently unconscious. When asked to imagine making a fist or wiggling their toes in response to hearing a beep, these patients displayed brain activation comparable to that of healthy volunteers given the same task.

This result adds to earlier evidence (here and here) from functional magnetic resonance imaging (fMRI) that found that some patients considered vegetative showed brain activation identical to healthy volunteers when asked to imagine engaging in tasks such as playing tennis, moving around a room in their homes, or responding to a question. Studies on a limited number of patients diagnosed as being in a persistent vegetative state have found that between 10 percent and 20 percent of them show brain activation indicative of consciousness on either fMRI or EEG. Although the meaning of the studies is not without controversy, it seems reasonable to interpret them as demonstrating consciousness in some of patients considered vegetative based on expert clinical examination.

The EEG findings have immediate clinical implications. Unlike fMRI, which is a research tool not readily available in clinical settings, EEG can be brought to the bedside, is much less expensive, and is minimally intrusive.

In response to this stunning development questions need to be posed and pondered relating to three issues: (1) further testing and refinement of the potential for EEG to probe consciousness in vegetative patients, as well as other patients with related profound brain disorders; (2) technological ways to communicate with these patients to enhance their quality of life; and (3) end-of-life decision-making.

The expansion of scientific knowledge often opens up new areas of uncertainty. Clearly, the validity of EEG to detect consciousness needs to be confirmed by further research. As is the case with any diagnostic technology, there is a risk of false positives and false negatives: some patients thought to be conscious may be exhibiting only unconscious brain activity; others may be conscious even if they do not display signs of consciousness on EEG. But they might be judged conscious if tested with fMRI or some new technology.

Beyond diagnosis lie important questions about whether and how EEG can be used to communicate with seemingly vegetative patients. In addressing this issue we are not completely in the dark. The analogous situation of patients in a locked-in state, with intact consciousness and the ability to communicate via blinking an eye, deserves attention.

These patients can communicate their quality of life and autonomous preferences for treatment without speech or conventional sign language. A key difference, however, is that with locked-in patients, clinicians and family members can readily interpret the meaning of eye blinks, as is so vividly represented in the remarkable book, The Diving Bell and the Butterfly, composed and dictated by Jean-Dominique Bauby while in a locked-in state. But interpretation of signals recorded by EEG or fMRI is more open to question, especially in the early stages of scientific investigation and clinical applications. Uncertainly about interpretation of brain signals might be mitigated in the future if it is possible for patients to respond to questions and initiate communication with the aid of computer technology.

The potential to communicate with patients who have no clinically detectable signs of consciousness raises a host of questions about understanding and enhancing their quality of life. Are they in pain? How can pain be assessed? If they are in pain, can it be relieved without sedation diminishing or extinguishing consciousness? Does a patient want to be wheeled outdoors or listen to music? And, more generally, what are these patients entitled to receive to optimize their quality of life?

Clearly, if EEG is eventually used routinely to assess consciousness for patients who appear to be vegetative, we need to explore the implications for end-of-life decisions. For patients without any signs of consciousness, there is no reason to change end-of-life decision-making approaches. While the possibility of a false negative diagnosis of lack of consciousness cannot be ruled out, it should still be up to surrogate decision-makers, in consultation with clinicians, to determine whether to continue life-sustaining treatment, based on the prior preferences and values of the patient, if known, or what they judge to be in the patient’s best interest.

A major challenge concerns those patients who are able to respond to commands and questions by means of EEG. How will their decision-making capacity be assessed? How can we be confident that technologically-mediated communication with these patients can represent their autonomous choices in making fateful decisions about whether to continue living or to stop life-sustaining treatment?

As we reflect on the latest research in this domain and its implications at the bedside, we should also ponder with fascination and humility how science transforms and complicates medical ethics.

Franklin G. Miller, Ph.D., is a member of the senior faculty in the Department of Bioethics, National Institutes of Health. Robert D. Truog, M.D., is a professor of medical ethics, anesthesiology, and pediatrics at Harvard Medical School and a senior associate in critical care medicine at Children’s Hospital Boston. The opinions expressed are the views of the authors and do not necessarily reflect the policy of the National Institutes of Health, the Public Health Service, or the U.S. Department of Health and Human ServicesRead more: http://www.thehastingscenter.org/Bioethicsforum/Post.aspx?id=5633&blogid=140#ixzz1f898fjeh

In a second article on the subject, Rabbi Avi Shafran shares his explanation of how Jewish Medical Ethics would look at the newest findings.  For him, he returns to Terry Schiavo, and asks whether she would have responded differently if someone had read her EEG and known what questions to ask to elicit a legitimate response.  I will excerpt his piece below:
 

Remember Terri Schiavo, the “vegetative” Florida woman who, as a result of her husband’s insistence and a court order (over her parents’ objections), was removed from life support and died in 2005?

“Vegetative” patients—people who, due to disease or accident, are unresponsive to stimuli—are considered by many to be less than truly alive…

Of course, even in the absence of evidence of any brain activity detectable by machines we have now no one can know what degree of consciousness persists in a body unable to move. But a diagnosis of “permanent vegetative state” can make it lawful to withdraw assisted nutrition and hydration—in other words, to starve the patient to death.

A different issue is “brain death”—a diagnosis of irreversible cessation of all brain function, which modern medicine and secular law consider sufficient to permit the “harvesting” of organs before removal of life-support. In the eyes of halacha, can such a patient, whose heart is still beating, in fact be considered a warm corpse?

Some rabbis say yes. But many of the most prominent halachic authorities, including Rav Shlomo Zalman Auerbach, zt”l, and yibodel lechaim, Rav Yosef Elyashiv, disagree. Leading halachic lights in the United States who concur with those poskim include Rabbi Herschel Schachter and Rabbi J. David Bleich.

(Halacha, to be sure, does not always insist that life be maintained; in some cases of seriously ill patients, even those with full brain function, it even forbids intercessions that will prolong suffering. But Judaism considers life precious, indeed holy, even when its “quality” is severely diminished. And so, halacha does not permit any action that might hasten the demise of a person in extremis. And, needless to say, it forbids removal of vital organs from a patient not deemed by halacha to be deceased.)

Back in 2005, Princeton University Professor of Bioethics Peter Singer was asked by The New York Times what today-taken-for-granted idea or value he thinks may disappear in the next 35 years. He responded: “the traditional view of the sanctity of human life.” It will, he went on to explain, “collapse under pressure from scientific, technological and demographic developments.”

The professor, unfortunately, is likely right about society’s regard for human life—particularly as life-spans increase, insurance costs rise, and demand for transplantable organs intensifies. Human beings run the risk of morphing from holy harborers of souls into… commodities.

Ironically, though, Singer may be wrong about technological developments. As events of late have shown, the creative use of technology can upend our assumptions about things like “vegetative” patients, and act as a brake on the “progress” of the commoditization of human life.

Would an EEG have yielded any sign of consciousness in Terri Schiavo’s unresponsive body? Doctors say it is unlikely, that her brain was likely too deeply damaged.

But of course we’ll never really know.

I will withhold comment on the issue of brain death (which should really be termed brain-stem death, as there is an ethical and halachic difference).  What strikes me is that since Terry Schiavo’s death, she has been used as a cause on both sides, for those who are fearful of hospice/end-of-life care and for those who feel it should have been done sooner.  For example, many in the the Orthodox Jewish world have used her story, incorrectly, as proof that because she was on hospice, all hospices must be dangerous and want to end life sooner.  This article is an example of that.  To assume that simply because we could read someone’s brainwaves on EEG would mean that they might be able to communicate something is challenging, as the first article indicates.  As such, Rabbi Shafran’s conclusion is somewhat misleading, because who is to say brainwaves proves that a person is mentally competent to make a decision.  Obviously, more medical experimentation is needed to get a better understanding of what is being seen through the EEGs. 

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