More Rigorous Test Omitted
It should be noted that steps are taken to prevent the donor from becoming short of oxygen while the ventilator is temporarily disconnected for these test purposes. This is to preserve the donor organs from anoxic damage which would impair their suitability for transplantation. However, this inevitably means that the vital centre in the brain stem which 'controls the breathing - the respiratory centre - is not subjected to the ultimate stimulus (lack of oxygen in the blood reaching it) to see if it can make a last-gasp effort. It is, in fact,tested only for the ability to respond to the less-powerful stimulus of a high carbon dioxide content in the blood still reaching the brain stem.
It should also be noted that the vital centres in the brain stem which control heart-rate and blood pressure are not tested at all under the U.K. protocol. That they are still active in some, if not most, organ donors is shown by the fact that many of them continue to maintain their blood pressure naturally after the declaration of "brain stem death," and by observations of cardiovascular response to the trauma of organ removal which are almost certainly brain stem mediated.
The long and short of it is that these tests are nowhere near adequate to exclude residual life and function in a damaged brain. And, as if that were not bad enough, not even all of these tests have to be done when it is desired to certify death for transplantation purposes. In other countries, there is at least some attempt to test for residual activity in the higher centres of the brain. In the U.K. there is none. If persisting electrical activity (EEG waves) were sought here, it is certain that it could be found in many of these so-called "cadaveric" organ donors. Some would retain function in a part of the brain which controls glandular secretions. These discomforting facts are simply ignored by those who wish to call a donor's brain dead. They dodge the issue of their relevance by not doing the tests which might demonstrate such activity.
The Brief: to Provide Organs in Good Condition
In effect, exhaustive testing for residual life in the brain is proscribed. All in all, the rules governing the diagnosis of "brain death"in this country must be seen for what they are - a simplistic code developed in response to a brief to provide vital organs in good condition for the transplanters. A colleague has likened the process of their formulation to the activities of a committee of foxes taxed with the design of a hen house .....
From the scientific point of view, it is most unfortunate that attempts to diagnose true death of the brain, while some independent bodily functions continued, ever became involved with transplantation. As we have seen, the idea that it might be diagnosable, in some circumstances,was seized upon by those seeking viable human organs, long before it had been adequately thought out or tested. The transplanters simply assumed that what they wanted to believe was true - and have steadfastly refused to consider, or even see, the substantial body of evidence that denies their belief. Had they not become involved, with the consequences that ensued, we might by now be further along the road towards the possibility of secure diagnosis of the true and total death of the brain as an independent phenomenon.
Should that become a scientific reality, the term "brain death" would be an appropriate description. And I, for one, would be prepared to consider the proposition that a patient with a truly dead brain was no longer a human being, i.e. because there is persuasive evidence that the brain is the quintessential organ and the home of the inner self.
PART V
A Better Criterion
However, the final 'cessation of all activity in every part of the brain would be a prerequisite for consideration of this proposition because Man does not yet know very much about the workings of his brain and we cannot, therefore, safely assume that pockets of residual activity here and there do not matter. That being so, we should need clear evidence of the absence of all metabolism, with no possibility of its resuming, in each and every part of the brain. Reliable evidence of the final cessation of blood flow (at normal temperatures) everywhere within the brain would be acceptable for this purpose and it is possible that techniques with the power to demonstrate this reliably (while the body is still alive) may one day become available. At the moment, we can only be sure that the cerebral circulation has ceased for ever when the bodily circulation has finally ceased, i.e. when the patient's heart, or some other pump such as those used in operating theatres to take over the heart's function while it is operated upon, finally stops. This, of course, is the commonly understood criterion of death and the one still used by the majority of the world's doctors to diagnose well over 99% of all deaths.
To sum up, I would urge that:-
(1) The attempt to force upon the professions and public the notion that true death of the brain can be ‘diagnosed reliably, while the body is still alive, be resisted. Likewise the contingent notion that a patient pronounced "'brain dead" on current criteria is truly dead.
(2) It it be argued that the state defined by the "brain stem death" tests is, while not death itself, yet so close to death as to make no practical difference, let the inaccurate and misleading term be abandoned in favour of one which makes the situation clear, i.e. that neither the patient nor his brain stem is really dead at this time, though doomed he may well be. Full understanding of this essential point will perhaps for the first time, enable the opinion-formers of our society to debate the ethics of transplantation in an enlightened frame of mind. Up till now, the highly successful confusion of the dying and dead states, andthe use of weasel-words such as "beating-heart cadavers," has manipulated thought to the exclusion of serious criticism.
(3) The misleadingly-worded Donor Cards be withdrawn immediately.
Many selfless prospective offers may have been made on a basis of serious misunderstanding; the signatories may have thought that the words "after my death" on those cards meant after their deaths in the commonly-understood sense of the term. Indeed, I know that some highly-intelligent and otherwise well-informed people have carried these cards thinking that they were thereby authorising removal of their organs after the final disconnection of the ventilator and the subsequent final cessation of their circulation. When disabused of this cosy notion, some have expressed horror and some disbelief. Most, when the truth has dawned, have destroyed their cards; a few have continued to carry them after modification, e.g. specification that a general anaesthetic be administered during removal of the organs.
To be continued ...
No comments:
Post a Comment