Medical advances offer new definition of death

Dr Andy Ho wrote that the category of brain death was introduced "explicitly to free up intensive care unit beds and increase the supply of organs for transplantation" ("Do not leave definition of death just to doctors"; Aug 22).

However, the very article he referenced - A Definition Of Irreversible Coma, published in the Journal of the American Medical Association in 1968 - states that the primary driver for this revised definition was "improvements in resuscitative and supportive measures", leading to obsolescence of the pre-existing criteria of death.

Although the issues of bed occupancy and organ donation are key issues affected by a revised definition of death, it is clear that these are among the myriad of secondary outcomes which have emerged due to this new clinical state made possible by advancements in medical care.

Prior to the 1960s, death was defined almost exclusively by cessation of cardio-respiratory function. This was also a time when those with severe illness were likely to succumb to their pathology, making this definition of death elegantly simple and reliable.

However, since then, numerous advancements in medical science have enabled doctors to successfully resuscitate patients who would previously have died, leading to scenarios where an individual may have a heartbeat, but whose brain has been so severely damaged by illness that there is no discernible residual function.

The reverse has also been made possible - patients on life-support systems may have no meaningful heart or lung function, yet may be awake and communicative.

These scenarios clearly highlight the inadequacies of the traditional understanding of death, and the necessity of a more robust definition. Hence, the introduction of the category of "brain death" was not "just changing the definition of a biological condition" but, rather, a revision of pre-existing paradigms in the light of a new biological state that was brought about by modern medicine.

It was primarily the need to bring clarity to confused and grieving loved ones that drove this revised definition, and not the economic considerations that Dr Ho highlighted.

Tan Sing Chee (Dr)