Cherishing Life, the Bishops’ 2004 document on the moral and spiritual well-being of the human person in society, offers clear definitions of subjects concerned with the dignity of life from conception to natural death.
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In ordinary circumstances death is diagnosed on the basis of irreversible loss of breathing and heartbeat. However, when a patient is on a ventilator the diagnosis of death is more difficult. In these circumstances medical authorities in the United Kingdom have accepted brainstem death as the death of the patient on the grounds that it inevitably causes the collapse of the bodily system as a whole.
In his Address to the Transplantation Society in August 2000, Pope John Paul II accepted as a criterion for ascertaining death ‘the complete and irreversible cessation of all brain activity’ but only on the understanding that this can be considered ‘the sign that the individual organism has lost its integrative capacity.’
In 1998 the Department of Health suggested as a definition of death ‘the irreversible loss of the capacity for consciousness combined with the irreversible loss of the capacity to breathe’. The government has subsequently asked for comments on this definition. From a philosophical and theological standpoint, this cannot be considered an adequate definition of death. The ability to breathe spontaneously is one feature of a living body, but it is by no means the only such feature. More thought must be given to what constitutes the functioning of a living body and how to determine when ‘the individual organism has lost its integrative capacity’ (Pope John Paul II, Address to the Society for Organ Sharing, 1991). If the body retains its capacity to function as a living whole then it is alive, even if the capacity for consciousness is lost. Someone who is in a coma or who is in a persistent unconscious state, is not actually dead and medical authorities rightly distinguish persistent unconsciousness from biological death. Death must not be redefined so that it includes patients who are alive but who are judged to be ‘as good as dead’.