At one point in the enduringly popular movie Princess Bride, the hero Wesley apparently dies. But his companions take him to Miracle Max who reassures them by saying: “it just so happens that your friend here is only mostly dead. There is a big difference between mostly dead and all dead. Mostly dead is slightly alive”. Then he proceeds to revive him.

It’s a quirky scene in which the play on words is used with masterful effect: everyone knows you can’t be mostly dead or slightly alive.

Yet in real life, the line between life and death isn’t always so easy to recognize — due to the incredible capacities of the modern Intensive Care Unit (ICU). Specifically, when patients have suffered such extensive brain injury that they are declared “brain dead” while still being artificially maintained (principally on a ventilator), does this mean all dead or just kind of mostly dead?

Brain death, unlike other severe conditions such as the Persistent Vegetative State, does constitute death, but it is still rather poorly understood, even among some medical practitioners. So it is understandable that family members of those declared brain dead frequently feel their loved-one really died when the ventilator was removed or their organs were extracted for donation.

Some even suspect their loved-one “died twice”, which is an impossibility – unless you are Lazarus, whom St Stephen extols in C.S. Lewis’ poetic imagination, because he

… obediently
put out a second time to sea
well knowing that [his] death (in vain
died once) must all be died again.

Shakespeare also said (in Julius Caesar) that a coward “dies” multiple times before death, whereas the valiant experience death only once. This strikes a chord because we appreciate there are things worse than death, but everyone knows that death is a single event.

Is ‘brain death’ a valid criterion?

So why has the Catholic Church consistently signalled support for the proposition that brain death – death as determined by a stringent set of “neurological criteria” – is a valid means of establishing that death has indeed occurred?

The Church does not make technical decisions, but first listens to what those with the relevant medical competence have to say. And they overwhelmingly assert that death necessarily entails the irreversible destruction of the entire brain — including the brainstem (which among other things regulates breathing). Nowadays all other vital organs can be replaced, but there is no way to overcome the total, irreversible loss of all brain function.  

The irreversible loss of all critical brain function is the only condition that is both necessary and sufficient to establish death.

This may come as a surprise to many people, since it means that the other method of determining death – the traditional, seemingly obvious method of observing the stoppage of heartbeat and circulation – is reliable only when it persists long enough for the brain to die. Indeed, medical understanding today leads us to the conclusion that total brain death is not just a valid means of determining death, but ultimately the only one.

Then it is necessary to assess whether or not the prevailing medical judgment aligns with a sound Christian anthropology. That is where things get interesting, because “Christian anthropology” entails the recognition that man is comprised of the union of body and soul – and that death is defined by their separation. This is obviously something that cannot be directly observed or measured by the tools of modern science.

It must be kept in mind that the soul cannot be identified with any particular organ (such as the brain or the heart). The soul, as noted in the 2nd century Letter to Diognetus, “is present in every part of the body, while remaining distinct from it.” Death entails the irreversible loss of all the capacities (intellective, sensitive, and vegetative) of the spiritual soul. Even if someone does not appear able to exercise any of his intellectual powers or to retain his sensitive capabilities, he is not dead if he is still able to exercise his vegetative (most basic bodily) functions on his own.

Death, as the mediaeval philosopher and theologian Thomas Aquinas argued, ultimately occurs only when the soul is no longer capable of demonstrating or expressing its vegetative capacities under its own power. Bodily functions persisting only on account of medical intervention do not therefore appear attributable to the soul.

The moral certainty of death

So when a person unambiguously meets the criteria for brain death, we can say with moral certainty that the person has died. And a moral or prudential standard of certainty, rather than absolute certainty is the appropriate standard because it allows for conscientious decision-making based on the available knowledge, even amidst any conceivably remaining ambiguities.

Some who think that Brain Death (the Neurological Criteria) is not reliable or sufficiently rigorous suggest that we should return instead to the traditional heartbeat standard of determining death (the Circulatory Criteria); after all, shortly after cardiac arrest such donors appear “more” dead than the brain dead donor still being artificially maintained on a ventilator.

A sizeable and growing proportion of organ donation happens by this “circulatory criteria” nowadays. Here’s how it works: life support is withdrawn from gravely afflicted patients who are not brain dead because no viable treatment options remain. In these scenarios, death is foreseeable, and organ donation is scheduled to coincide with it.

Unlike brain death, which is a retrospective determination – an acknowledgment that death has already occurred – the circulatory criteria is prospective in nature; it requires a waiting period to establish death, but organs can quickly become unusable if too much time elapses.

These protocols typically call for organ procurement to begin 2-5 minutes after cardiac arrest.

But this, medical authorities say, is not enough time to know that the donor is conclusively dead, because the cessation of heartbeat and circulation needs to endure long enough for the brain to die in order to establish death. Prior to that point, it remains possible that they could be revived, even though no attempts at resuscitation would be made in these situations. But the concern is with establishing whether a person has actually died, not whether it would be wrong to try to revive him.

So this “traditional” means of determining death actually turns out to be less certain than the neurological criteria (in the context of organ donation) — as the medical authorities themselves plainly concede. Some medical authorities offer other justifications for these protocols – but they do not generally insist that these donors are dead, as they do with brain death protocols.

The dead donor rule

The entire organ transplantation enterprise is founded upon respect for the dead donor rule, the agreement that vital organs may only be removed after death.

But these extremely time sensitive protocols risk transforming the dead donor rule into the “soon to be dying donor rule.” This could open the door for justifying other, more radical proposals for organ transplantation before the donor dies.

We may evidently conclude that the requisite moral certainty of death is lacking in these circumstances; it should also be noted that many health professionals express serious qualms about these protocols based on the circulatory criteria.

Yet few prospective donors – or their loved-ones – are aware of the different scenarios in which their organ donation could actually take place. Few ponder they may not be dead at the time of donation, or that the bedside experience of observing and processing the moment of death could be abruptly truncated by the need to move with such haste.

This overall topic is much more involved and fascinating than it may first appear. I certainly never thought I’d write a prize-winning book about it. And especially for those inclined to become organ donors, these particulars are worth some extended reflection.