… The truth behind organ donation & organ transplants
By Dr David W Evans *
The term ‘brain death’ came into common use amongst those working in Intensive Care Units (ICUs) some 40 years ago. It was not coined in any formal way as the name of a defined clinical syndrome. It was used in communication between ICU staff as a “shorthand” term to describe the state of patients who showed no sign of being able to breathe on their own after many days of mechanical ventilation, and whose coma appeared profound and deepening. When they lay inert and unresponsive, with circulatory instability and no external sign of brain function, they were often (and increasingly) described as ‘brain dead’.
While there was, as I understood it, a general feeling that the brains of these patients were irrecoverably “out of business” - as a result of the trauma or disease process which had caused the apparently mortal brain damage - there was no pretence to certainty that there could be no residual life anywhere within those brains. It was recognized that the clinical evidence available could not support formal diagnosis of death of the whole of those brains as a matter of fact. There may have been, in the minds of the medical staff, an element of hope that they were really and truly dead - a hope strengthened if electroencephalography (EEG) was available and had recorded no intrinsic electrical brain activity from scalp electrodes - for the clearly hopeless prognosis posed a management problem to which the only humane solution seemed to be discontinuation of life support to allow death to occur. However, it was noteworthy and indeed inspiring to see members of the nursing staff still treating these inert and apparently insentient patients with gentle care, calling them by name and talking to them as if they might be comforted thereby.
The decision to discontinue life support was not, as I recall, uniquely difficult amongst the many onerous decisions which had to be made by those members of the medical staff with the seniority required for exercise of responsibility in acute salvage and intensive care medicine. In those days when there was, perhaps, greater trust in the medical profession than exists today, there was no question of that decision being influenced by any consideration other than the interests of the patient and the peace of mind of the relatives and those caring for him. It was the practice to seek a consensus on the proposed action, by discussion with all those involved, after medical agreement about the futility of further life-sustaining treatment had been reached. The latter process included specialist neurological opinion when available, although it could usually do no more than confirm the potentially lethal nature of the brain damage, the depth of coma and the absence of reflexes (especially some of those with arcs which pass through the brain stem). Confirmation of ventilator dependence required that the ventilator be disconnected for long enough to be sure that the brain stem respiratory centre was no longer responsive (the apnoea test). That test, while of crucial management importance, was known to carry risk of exacerbating the already critical situation. It was, therefore, carried out only when a secure consensus that futile treatment should be discontinued had been reached. Then, if there was no sign of respiratory effort after prolonged disconnection - typically 10 minutes or more - there was, of course, no reason to re-establish mechanical ventilation.
In those early days of intensive care, practices inevitably varied between units - though within narrower limits as experience accrued - and national guidelines aimed at standardizing recognition of the state which might have been called mortal brain damage were clearly desirable. Conformity in the diagnosis of this state, with its attached fatal prognosis and management imperative, offered greater comfort and security to all concerned. News that the UK Conference of Medical Royal Colleges was preparing such guidelines was, therefore, welcomed. Its report, published in 1976, (1) formalized the procedure to be used in establishing the futility (and impropriety) of continuing life support measures in comatose, ventilator-dependent patients. Its stated purpose was “to establish diagnostic criteria of such rigour that on their fulfilment the mechanical ventilator can be switched off, in the secure knowledge that there is no possible chance of recovery.” (2) It specified the conditions to be satisfied before testing is carried out, with caveats about exclusion of cryptic causes of coma, and detailed the brain stem reflexes to be sought. The crucial apnoea test was limited to stimulation of the respiratory centre by potent hypercarbic drive, the ultimate anoxic drive stimulus being avoided by pre-oxygenation and diffusion of oxygen throughout the 10 minute disconnection period. Resumption of mechanical ventilation was then envisaged, to allow for repetition of testing at some arbitrary interval - “to ensure that there has been no observer error” - and, presumably, if there was no observed respiratory effort on the second occasion, to keep the patient alive for a while longer in the interests of organ transplantation (the report was “written with the advice of the sub-committee of the Transplant Advisory Panel” - hence, perhaps, the less than stringent apnoea test).
Setting aside that glimpse of transplant interests even at that stage, and taking this Code of Practice (as it became known) at face value, the diagnostic criteria laid down in that 1976 report served the purpose of defining a clinical syndrome to which an apparently unalterable short-term fatal prognosis attached, any and all further treatment being pointless and unkind. In the report’s words “They are accepted as being sufficient to distinguish between those patients who retain the functional capacity to have a chance of even partial recovery and those where no such possibility exists”.“… its criteria were clearly inadequate for the de facto diagnosis of brain death, only a minute portion of the brain being tested at all” It is unfortunate that Conference’s report was published under the title “Diagnosis of Brain Death” - using the imprecise colloquial term in a formal and potentially misleading sense - for its criteria were clearly inadequate for the de facto diagnosis of brain death, only a minute portion of the brain being tested at all and even those few more sensitive tests of global brain life and function which were available at the time being actively discouraged.
So that’s what ‘brain death’ really is, viz. a pre-terminal clinical syndrome defined by criteria which, in the light of advances in the understanding of brain function and its powers of recovery, and the means of testing for it, can be expected to need modification as time goes by. In the nature of scientific progress, technologies with greater sensitivity and specificity will emerge and may, along with new therapeutic possibilities, demand a revision of clinical practice in this presently dark field to a degree which might constitute upheaval. It is essential, as in all fields of scientific endeavour, that the minds of those involved remain ever open to these possibilities.
As clinically diagnosed in accordance with the UK Code of Practice, ‘brain death’ is not the state in which it can be confidently said that there is no remaining life anywhere within the brain. The bedside tests prescribed simply lack the power to exclude persisting function - some of which is demonstrable by other means, which are not used - and still less can they detect elements of the brain which, though currently functionless, may yet retain power of recovery under optimal conditions. That being so, and since death is not a positive state and can be defined only in terms of the absence of life, it would be unscientific and intellectually dishonest to say that brains pronounced “dead” on the basis of the 1976 UK criteria are really and truly dead. Sadly, and seemingly without realizing the risk to its scientific credibility, the Conference of the UK Medical Royal Colleges issued a Memorandum in 1979 which claimed that “brain death [as diagnosed by their 1976 criteria] represents the stage at which a patient becomes truly dead, because by then all functions of the brain have permanently and irreversibly ceased” (my italics). (3) That manifestly false claim was not formally abandoned until 1995, when it was “suggested that the more correct term ‘brain stem death’ should henceforth replace the term ‘brain death’ used in previous papers produced by the Conference of Colleges and the Department of Health”. (4)
While undeniably “more correct”, the term ‘brain stem death’ is nonetheless scientifically inappropriate to describe the clinical syndrome diagnosed by Conference’s Code of Practice, the elements of which have remained essentially unchanged since their promulgation in 1976. The prescribed testing of brain stem function is not rigorous, it ignores evidence of persisting medullary cardioregulatory function, and it declines to make use of special techniques which can reveal active brain stem neural pathways. (5) Put simply, brain stems pronounced “dead” on the UK Code of Practice criteria cannot, with scientific integrity, be described as truly dead. (6)“The prescribed testing of brain stem function is not rigorous, it ignores evidence of persisting medullary cardioregulatory function, and it declines to make use of special techniques which can reveal active brain stem neural pathways.”
The deceptive argument that death of the brain, and therefore of the person, could be diagnosed clinically while the body remains alive and perfused by its naturally-beating heart, appears to have had its origins in Cape Town in 1967. (7) The 1968 Ad Hoc Harvard Committee charged with examining brain death gave it formal status - but, as Veatch now reveals, “none of the members was so naïve as to believe that people with dead brains (sic) were dead in the traditional biological sense of the irreversible loss of bodily integration”. (8) Instead, they “proposed an entirely new definition of death, one that assigned the label ‘death’ for social and policy purposes to people who no longer are seen as having the full moral standing assigned to other humans”. Whether or not that was the understanding of those who subsequently enacted legislation allowing the certification of death on ‘brain death’ criteria in the USA, there seemed to be a worldwide willingness to follow that lead. The concepts of death which the criteria in current use are held to uphold have been the subject of much philosophical debate, the level of public understanding of which should be a matter of concern. (9) The variety of the diagnostic criteria (10) belies their ability to identify a discrete clinical entity - or even, with the desirable certainty, a syndrome with an inevitably imminently fatal outcome.
In the UK, equation of ‘brain death’ (as diagnosed by the 1976 criteria) with death of the person was evidently (in 1979) based on the concept that true and total death of the brain - later modified to “death of the brain as a whole” - self-evidently suffices for the purpose. ‘… there is no sound scientific basis for the diagnosis of human death on the so-called “brain death” or “brain stem death” clinical criteria in current use worldwide.’ When the claim that the Code of Practice tests had the power to diagnose the irreversible loss of all brain function became manifestly untenable, Conference’s 1995 Working Party “suggested that ‘irreversible loss of the capacity for consciousness, combined with irreversible loss of the capacity to breathe’ should be regarded as the definition of death”. (11) As a concept of human death, that concept might not find wide philosophical acceptance - still less, perhaps, the general public understanding and acceptance which seems necessary in regard to so important a matter as human death. But, from the scientific point of view, debate about that aspect must be seen as of little practical relevance in light of Conference’s false claim that clinical diagnosis of the syndrome it now calls ‘brain stem death’ suffices to exclude all possibility of the resumption of breathing or consciousness. Their specified apnoea test is not rigorous enough to ascertain the death of the brain stem respiratory centre. (12) Consciousness is not understood. Knowledge of what might be termed the minimal neuroanatomical substrate necessary for its arousal is lacking. There is, therefore, no means at present of testing for remaining life in such elements - still less for the possibility of recovery or regeneration of such elements in brains which are, to all available means of enquiry, silent at the time of testing.
In the present state of knowledge, there is no sound scientific basis for the diagnosis of human death on the so-called “brain death” or “brain stem death” clinical criteria in current use worldwide.
** Contribution to the Vatican conference, February 2nd - 4th 2005
* INSERIRE CURRICULUM
1. Conference of Medical Royal Colleges and their Faculties in the United Kingdom, Diagnosis of brain death, in “British Medical Journal”, 2, 1976, pp. 1187-1188.
2. Ibid., p. 1187.
3. Conference of Medical Royal Colleges and their Faculties in the United Kingdom, Diagnosis of death, in “British Medical Journal”, 1, 1979, pp. 332.
4. Working Group of the Royal College of Physicians, Criteria for the diagnosis of brain stem death, Review by a Working Group convened by the Royal College of Physicians and endorsed by the Conference of Medical Royal Colleges and their Faculties in the United Kingdom, in “Journal of the Royal College of Physicians”, 29, 1995, pp. 381-382.
5. D.W.Evans. The demise of ’brain death’ in Britain, in Beyond brain death - the case against brain based criteria for human death, edited by M.Potts, P.A.Byrne, R.G.Nilges, Kluwer Academic Publishers, Dordrecht,2000. R. Facco, M. Munari M, F. Gall, S.M. Volpin, A.U. Behr, F. Baratto, G.P. Giron, Role of short latency evoked potentials in the diagnosis of brain death, in “Clinical Neurophysiology”, 113, 2002, pp. 1855-1866.
6. D.W. Evans, D.J. Hill, The brain stems of organ donors are not dead, in “Catholic Medical Quarterly”, 40, 1989, pp. 113-121.
7. R. Hoffenberg, Christiaan Barnard: his first transplants and their impact on concepts of death, in “British Medical Journal”, 323, 2001, pp. 1478-1480. D.W. Evans, Barnard’s first transplants and concepts of death. Response to Hoffenberg, in “British Medical Journal”, 2001: http://bmj.bmjjournals.com/cgi/eletters/323/7327/1478#18279. See also responses from Coimbra, Hill, Jarvis, Potts and Woodcock to Hoffenberg’s article, on this site.
8. R.M. Veatch, Abandon the dead donor rule or change the definition of death?, in “Kennedy Institute of Ethics Journal”, 14, 2004, pp. 261-276 (p. 267). See also other articles therein.
9. The definition of death, edited by S.J.Youngner, R.M.Arnold, R.Schapiro, Johns Hopkins Press, Baltimore and London, 1999. M. Lock, Twice dead - organ transplants and the redefinition of death, University of California Press, London, 2001. Revisiting brain death, special issue of the Journal of Medicine and Philosophy, 26, 2001, edited by B.A.Lustig. K.G.Karakatsanis, J.N.Tsanakas, A critique on the concept of "brain death", Issues in Law & Medicine, 18, 2002, pp.127-141. R.D.Truog, W.M.Robinson, Role of brain death and the dead-donor rule in the ethics of organ transplantation, Critical Care Medicine, 31, 2003, pp. 2391-2396. Brain death and disorders of consciousness, edited by C.Machado, D.A.Shewmon, Kluwer Academic/Plenum Publishers, New York, 2004.
10. Brain Death, edited by E.F.M. Wijdicks, Philadelphia, Lippincott Williams & Wilkins, 2001; E.F.M. Wijdicks, Brain death worldwide: accepted fact but no global consensus in diagnostic criteria, in “Neurology”, 58, 2002, pp. 20-25 and in response D.W. Evans, Open letter to Professor Eelco F.M. Wijdicks, author of book on brain death, in “British Medical Journal”, 2002: http://bmj.bmjjournals.com/cgi/eletters/325/7364/598/a#27760.
11. Working Group of the Royal College of Physicians, Criteria for the diagnosis of brain stem death, Review by a Working Group convened by the Royal College of Physicians and endorsed by the Conference of Medical Royal Colleges and their Faculties in the United Kingdom, quoted, p. 381.
12. Vide supra.
The above is Dr Evans’ unedited contribution to “Finis vitae : is brain death still life?” , published by Consiglio Nazionale delle Richerche ISBN - 10:88-498-1698-7