Is Brain-Death Really Death?

An version of this article was printed in Humanism Ireland, May-June, Vol. 152 (2015) 

Until the second half of the twentieth century, there was little disagreement, at least within mainstream western thought, over the standard for human death. Death occurs when the heart has stopped beating and breathing has come to an end. The issue of whether or not someone is dead was generally held to be a simple question of fact. However, scientific and technological advances since the late 1950s—where the heart and breathing of patients could be artificially maintained by ventilators for weeks or months after all functions of the brain are irreversibly lost—have made the whole question more complex.

As a result of this, the Harvard Brain Death Committee—which included a number of medical professionals, lawyers and theologians—was established; in their landmark 1968 report they argued that the clinical standard of diagnosing death should be when the whole brain, or brainstem, has permanently ceased to function. The Committee, in other words, proposed a neurological requirement for determining death rather than the traditional cardiopulmonary one. Those who met the new criterion were now considered ‘brain-dead’. The redefinition also allowed doctors to turn off life-support when patients’ brains have ceased to function.

Following this, most developed nations—with the notable exception of Japan—have medically redefined death to something more closely in line with the Committee’s criterion. In Ireland and Britain, for instance, the definition involves death of the brainstem. Rather surprisingly, there was very little opposition to this widespread change—even the Vatican went along with it.  Nevertheless, there are some who remain sceptical: they argue that the concept of brain-death rests on shaky foundations, and it permits patients to be declared as dead before they really are.

Perhaps none of this is surprising—seeing that it’s now generally accepted that the main driving factors were pragmatic in nature. It was, by and large, a convenient way around the problem of overcrowding in hospital wards (not to mention the enormous costs involved) that materialised, consisting of patients on mechanical respirators with no prospect of recovery. By stating that brain-dead patients are dead, doctors no longer had to hold off until patients’ hearts stop beating before turning off respirators. The redefinition also enabled organs to be removed from patients whose brains had ceased to function; patients whose hearts continue to beat due to artificial respirators usually have healthier organs—ones that are less likely to deteriorate—if removed before the body has ceased to function. The redefinition, therefore, allowed surgeons to acquire a larger supply of viable organs for transplantation. Considering these points, we can see why some might view the redefinition as a legal fiction, invoked by authorities to get round a number of practical problems that have materialised due to the advances in medical technology.

A number of problems with recognising brain-death as death of the human organism have also been identified—both empirically and conceptually. To begin with, it assumes that when the whole brain has ceased to function, that is sufficient for the human organism to be declared dead. But why think of the brain as so important? (It’s worth mentioning also that some scholars (e.g., here and here) have pointed out that in some brain-dead patients minor brain functions often continue, such as the supply of various hormones that help modulate a number of bodily functions. In terms of whole brain death, does it matter that some functions remain?)      

Proponents of the brain-death standard maintain that cessation of integrated functioning of the organism is sufficient for someone to be classified as brain-dead. However, the paediatric neurologist, Alan Shewmon, has pointed out in a series of papers that some integrated functioning can occur without any contribution at all from the brain; for instance, in patients who are declared clinically brain dead, somatically integrated functions—such as homoeostasis, energy balance, wound healing, the fighting of infections, the proportional growth of brain dead children, and a number of others—are possible. Shewmon argues that the brain should be seen as more of an enhancer than an essential integrator of bodily functions. 

Proponents may insist that critical integrative functioning, that is controlled by the brain, is still essential in order to sustain life. After brain-death occurs, circulation of the blood and respiration are only possible with the aid of an artificial respirator, but nothing more than an externally supported but functioning body is insufficient for the presence of life. Instances like this, they claim, merely present a false appearance of life. The brain, it seems, is the only possible primary integrator. This suggests, according to defenders of the brain-death standard, that the human organism is deemed alive only if a satisfactory amount of functioning is integrated by the brain. But what should count as a satisfactory amount?  And, more fundamentally, why is it not possible for a human organism to be genuinely declared alive in cases where significant functions are only supported by artificial means? The philosopher David DeGrazia, for instance, points out that what’s important is not that the brain is maintaining the body’s functioning, but that there’s actually something there doing it.  

This notion is further challenged by considering patients suffering from extreme cases of locked-in syndrome—where there is significant, though not complete, destruction of the brain. Locked-in sufferers may be fully conscious (they are clearly alive!), but they may exhibit no more integrated functioning than brain-dead patients. The integrated functioning of a locked-in sufferer will have to be sustained by intensive medical support in order for him to survive, since the brain cannot do any integrating. According to brain-death theorists, the brain-dead patient is dead, but I doubt any of them would be willing to say the extreme locked-in patient is also dead.

Proponents of the brain-death standard will of course point out that the locked-in patient is still conscious, while the brain-death patient is not. Yet even if the capacity for consciousness is recognised as the underlying difference between the two cases, we will nevertheless have to abandon the condition that the brain must integrate the organism’s functioning for someone to be declared alive. Simply because someone’s integrated functioning is being externally supported—as the example of the extreme locked-in patient demonstrates—cannot be a sufficient reason for thinking that she is dead.

In light of this, some scientists and philosophers have abandoned the whole brain-death criterion and have proposed something even more radical in its place. The biological death of the human organism, according to this offering, ought to be defined as “the irreversible cessation of the capacity for consciousness”. This concept of death is usually referred to as ‘higher brain-death’ or ‘cortical death’. Proponents of this view argue that once the capacity or potential for consciousness is lost, one thereby dies. For this reason, it is permissible to withdraw feeding tubes and to remove organs for transplantation (assuming prior consent is given) after consciousness is irreversibly lost. The higher brain-death criterion, for the most part, still considers it paramount to determine whether or not someone is alive, as its proponents maintain that it’s wrong to intentionally take innocent human life. 

To be sure, many will regard the criterion for higher brain-death as highly dubious. For instance, patients who lapse into a persistent vegetative state (PVS) will meet this standard. The destruction of the cerebral cortex denies those in a PVS the capacity or potential for consciousness, but, nevertheless, they can often continue to breathe and sustain other vital functions, with little mechanical assistance, as the brainstem remains intact and functional; some of those in a PVS can also be maintained for several years, and sometimes even decades, by artificial feeding. To declare that PVS patients are not actually alive, as proponents of the higher brain-death criterion do, might be a bit too much for most people to digest.

A more fundamental problem with the higher brain-death standard is that it assumes the irreversible loss of consciousness is sufficient for the death of a human being in the biological sense. However, it’s generally acknowledged that young foetuses and certain anencephalic infants are living human organisms, despite the fact they are not conscious. If we accept that beings like this can live and die, then it seems we have to accept that there are some living human organisms that don’t possess the capacity for consciousness. On that account, and contrary to what higher brain-death proponents argue, having no capacity or potential for consciousness cannot be a sufficient condition for the death of the human organism. Seeing that anencephalic infants have a similar status to patients in a PVS, it seems rather odd, then, to regard the former as alive and the latter as dead.

In order to avoid this problem, one could deny that anencephalic infants are living beings as well. This move seems implausible, though, since they have each of the biological functions and capacities that ordinary human infants have (apart from those dealing with consciousness).  On top of that, I don’t believe many people (including proponents of the higher-brain dead criterion) would be comfortable with the idea of the cremation or burial of spontaneous breathing anencephalic infants or adults in a PVS.  

If the whole brain-death and higher brain-death standards are abandoned, what are we left with? Some claim the problem needs to be understood in a different way altogether. Instead of focusing on the question “at what point does the human organism die?” we should ask “what actually matters?” The philosopher Jeff McMahan argues that when the irreversible loss of the capacity for consciousness occurs, the person ceases to exist, while the human organism may continue to live. According to this view, the human organism does not necessarily die when the brain has ceased to function, but only when there’s cessation of breathing and heartbeat.

The question of when a human being loses moral status, McMahan claims, is not necessarily synonymous with the question of when the biological organism dies. Persons clearly have moral status: they are conscious, they have the capacity for self-control and autonomy, they can experience pleasure and pain, they have memories of the past and a sense of the future. On the other hand, living human organisms, where consciousness has been irreversibly lost, do not possess any of these attributes, so, therefore, they don’t matter in the same way as persons do. A similar view is expressed by Peter Singer in Rethinking Life & Death (1994): “The fact that a being is human, and alive, does not in itself tell us whether it is wrong to take that being’s life”. Rather than proposing contrived definitions of death, it’s more appropriate (and honest) to say that once consciousness has been irreversibly lost, it may well be permissible to withdraw external life support and remove organs, whether the human organism is deemed alive or not. (Of course, questions of prior consent will still have to be considered).

Once we accept that it’s consciousness—and not life—that gives us moral status, we will no longer be tempted to conjure up redefinitions of human death. Needless to say, this position stands contrary to the principle of the sanctity of human life, a doctrine than many people today still hold as unconditional and universal. But can, and should, atheists and humanists continue to uphold this doctrine? Can mere membership of the species Homo sapiens alone, irrespective of other characteristics, be sufficient for someone to acquire full moral status? The principle of the sanctity of human life is a relic of Christianity (i.e., that humans are separate and intrinsically unique from the rest of creation), and it persists in our secular world today.  It seems to me, however, that progress in technology and medicine are making it much more difficult to sustain this way of thinking.