Living after death.
Over the past three decades, organ transplantation has evolved from just an experiment in human biology to an accepted form of treatment for patients suffering from end-stage organ failures. Tissue transplantation has also undergone similar advances. It has become an accepted practice in areas as diverse as orthopaedics and ophthalmology. Newer drugs and improved skills of health professionals are making more and more transplants successful.
The ability of transplant centres to offer this effective treatment is limited by the availability of donor organs and tissues and many people are still dying or are crippled owing to the lack of possible donors. Today, in the more advanced countries, it is possible to transplant different organs and tissues, including corneas, kidneys, heart, liver, lungs, pancreas, intestines, skin, bone marrow, bones and cartilage from a single organ donor.
While tissues such as the cornea, bone and cartilage can be removed within hours of a cardiac arrest and still be suitable for transplantation, most other organs require a persistent blood circulation to be viable and to be of any use to the recipient after transplantation. It is in this context the concept of brainstem death has been evolved to define death before the heart stops beating. If organs could be removed from these individuals with brainstem death and a beating heart, they could be transplanted into the recipients suffering from various organ failures.
It is quite difficult to define “death”. Unless one defines death, the decision that a person is dead cannot be verified scientifically. This is because the available technical data cannot always answer a purely conceptual question.
Whereas the functions of the lungs and the heart can be taken over by machines for a finite extent of time, those of the brain cannot.
An individual can, therefore, be dead only when his brain is dead. Death can be defined as an irreversible loss of capacity for consciousness combined with the irreversible loss of capacity to breathe (and hence the ability to sustain a spontaneous heart beat). In such a situation even if ventilation is assisted by machines, the heart would stop beating in a matter of a few hours or days and the individual will be considered to be “dead” as one usually perceives death.
Death, thus conceived, can arise from primary catastrophes within the head, or it can be a consequence of an event elsewhere, like a cardiac arrest. Such a circulatory arrest will prove lethal if it lasts long enough for the brain stem to die. Therefore, all death in this perspective is brain stem death — is all the key functions that define a human being to be alive, i.e, the capacity to be conscious and the capacity to breathe (and in turn sustain heart beat) are subserved by the brain stem.