A long-established criterion for determining death is under growing scrutiny.
Thirty-six hours after Zack Dunlap had an accident last November with his souped-up ATV, doctors performed a PET scan on Zack and found there was no blood flowing to his brain. After informing his parents, the doctors declared Zack brain-dead. Then followed the call to the organ harvesting team to come and retrieve organs from Zack. As they were being flown in by helicopter to the Wichita Falls, Texas hospital where Zack lay presumably dead, nurses began disconnecting tubes from his inert body. It was only then that one of Zack's relatives who happens to be a nurse tested Zack for reflexes. Not only did Zack respond to pain, he was later able to tell a stunned television audience and Today Show host Natalie Morales that he heard the doctor declare him brain-dead, and how much that ticked him off.
Stories like Zach's seem to be more prevalent of late, and more disturbing. They occasion reasonable doubt about three related issues: the reliability of the brain-death (BD) criterion as a standard for determining death; the degree of rigor with which such determinations are made; and whether the medical establishment is not dangerously biased toward organ harvesting as opposed to long-term, potentially regenerative care for persons who meet the loosest standard for BD.
Until recently, the general consensus had been that BD -- the irreversible and complete cessation of all brain function -- constituted a sufficient criterion for establishing that a human individual has, in fact, died. However, the consensus surrounding BD has been challenged of late. Opponents, most notably Dr. Alan Shewmon, Chief of the Department of Neurology at Olive View Medical Center, UCLA, point to cases of individuals who have been declared brain-dead and have "survived" with the aid of artificial respiration/nutrition for weeks, months, and even years. Shewmon has published a controversial study of such survivors that has posed a diametric challenge to the neurological standard for determining death. In testimony before the President's Council on Bioethics, Shewmon observed:
Contrary to popular belief, brain death is not a settled issue. I've been doing informal Socratic probing of colleagues over the years, and it's very rare that I come across a colleague, including among neurologists, who can give me a coherent reason why brain destruction or total brain non-function is death.
There's always some loose logic hidden in there somewhere, and those who are coherent usually end up with the psychological rationale, that this is no longer a human person even if it may be a human organism.
The American Academy of Neurology (AAN) established a set of Guidelines for the determination of brain death in 1995 which currently remain a point of reference for many hospitals and physicians throughout the country. The AAN guidelines lay out diagnostic criteria for making a clinical diagnosis of BD. The guidelines note that the three "cardinal findings" of brain death are coma or unresponsiveness, absence of brainstem reflexes, and apnea (the cessation of breathing). It further outlines a series of clinical tests or observations for making these findings. The guidelines also note that certain conditions can interfere with clinical diagnosis, and recommends confirmatory tests if such conditions are present. Finally, the guidelines recommend repeated clinical evaluation after a six-hour interval (noting that such time period is arbitrary) using a series of confirmatory tests that are described in the document.
A recent study published in the journal Neurology, noting widespread variations in the application of the AAN Guidelines, drew these conclusions:
Major differences exist in brain death guidelines among the leading neurologic hospitals in the Unites States. Adherence to the American Academy of Neurology guidelines is variable. If the guidelines reflect actual practice at each institution, there are substantial differences in practice which may have consequences for the determination of death and initiation of transplant procedures.
Such variability in applying a uniform criterion of BD, in addition to the growing number of survivors of BD, must give us pause. And so must the growing societal pressure to donate organs -- notwithstanding the genuine hopes that organ transplants holds for millions of people.
That pressure arises from the fact that the numeric gap between available organ donors and patients who need organ transplants continues to grow every year. A recent survey indicated that in 2006 over 98,000 organs were needed for patients on US transplant waiting lists.
Complicating matters, the number of available organs through donation from brain dead patients has remained stable for a number of years. And while organ donor cards and growing use of advance medical directives have occasioned a slight increase in the numbers of cadavaric transplants, more organs are needed than are currently available.
Consequently, transplantation services are pressed to find new and ethically acceptable ways to increase the number of available organ donors. Some advocates of a less rigorous application of BD have gone so far as to openly consider the moral licitness of removing organs from anencephalic newborns, and from persons diagnosed as being permanently comatose or in a permanent vegetative state (PVS). And some members of the medical profession believe the solution lies in redefining BD so as to make it less restrictive.
One such approach would define BD (and consequently death itself) as cessation of all higher level (cortical) brain functioning -- even if there were activity in other areas of the brain. Such was the proposal suggested by Dr. Robert Veatch of the Kennedy Institute of Ethics at Georgetown University in his testimony before the President's Council on Bioethics two years ago. "We could shift to a new definition of death that would classify some of these permanently comatose persons as dead," affirmed Veatch. "In fact, a large group of scholars now in rejecting a whole brain definition has [endorsed]... a higher brain definition where some of these patients would be legally classified as dead."
"But would the ordinary citizen accept such a definition?" he then asked. In response, he pointed to a study done at Case Western Reserve University looking at the opinions of ordinary citizens in the State of Ohio. The results were startling. Of a population of 1,351 citizens who participated, 57% considered the person in permanent coma to be dead, and 34% considered the person in a permanent vegetative state to be dead. Furthermore-again on Veatch's interpretation of the data -- with regard to the propriety of harvesting organs, in the case of a more rigorous application of the BD criterion, 93% percent thought it acceptable take organs. But in the case of permanent coma, 74% would procure organs, and even in the case of PVS, fully 55% percent would procure organs.
Veatch ended by exhorting those present: "I suggest that it's time to consider the enormous lifesaving potential of opening the question about going to a higher brain definition of death or, alternatively, making exceptions to the dead donor rule."
Food for thought-and potentially for nightmares.
Admittedly, proponents of BD would question, in cases of survival after a BD determination such as that of Zach Dunlap, whether the criterion was applied strictly enough when they were declared brain dead. That's a legitimate question.