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Transplant Study Revives Questions Over When to Declare Donors Dead
作者:USMedEdu
发表时间:2008-08-20
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Transplant Study Revives Questions Over When to Declare Donors Dead

http://www.nytimes.com/2008/08/13/health/13transplants.html?ex=1376452800&en=de691a9817965b65&ei=5124&partner=permalink&exprod=permalink


Published: August 13, 2008

NEW YORK (AP) -- A report on three heart transplants involving babies is focusing attention on a touchy issue in the organ donation field: When and how can someone be declared dead?

For decades, organs have typically been removed only after doctors determine that a donor’s brain has completely stopped working. In the case of the infants, all three were on life support and showed little brain function, but they didn’t meet the criteria for brain death.

With their families’ consent, the newborns were taken off ventilators and surgeons in Denver removed their hearts minutes after they stopped beating. The hearts were successfully transplanted, and the babies who got the hearts survived.

”It seemed like there was an unmet need in two situations,” said Dr. Mark Boucek, who led the study at Children’s Hospital in Denver. ”Recipients were dying while awaiting donor organs. And we had children dying whose family wanted to donate, and we weren’t able to do it.”

The procedure -- called donation after cardiac death -- is being encouraged by the federal government, organ banks and others as a way to make more organs available and give more families the option to donate.

But the approach raises legal and ethical issues because it involves children and because, according to critics, it violates laws governing when organs may be removed.

As the method has gained acceptance, the number of cardiac-death donations has steadily increased. Last year, there were 793 cardiac-death donors, about 10 percent of all deceased donors, according to United Network for Organ Sharing. Most of those were adults donating kidneys or livers.

”It is a much more common scenario today that it would have been even five years ago,” said Joel Newman, a spokesman for the network.

The heart is rarely removed after cardiac death because of worries it could be damaged from lack of oxygen. In brain-death donations, the donor is kept on a ventilator to keep oxygen-rich blood flowing to the organs until they are removed.

The Denver cases are detailed in Thursday’s New England Journal of Medicine. The editors, noting the report is likely to be controversial, said they published it to promote discussion of cardiac-death donation, especially for infant heart transplants.

They also included three commentaries and assembled a panel discussion with doctors and ethicists. Many of the remarks related to the widely accepted ”dead donor rule” and the waiting time between when the heart stops and when it is removed to make sure that it doesn’t start again on its own.

In two of the Denver cases, doctors waited only 75 seconds; the Institute of Medicine has suggested five minutes, and other surgeons use two minutes.

State laws stipulate that donors must be declared dead before donation, based on either total loss of brain function or heart function that is irreversible. Some commentators contended that the Denver cases didn’t meet the rule since it was possible to restart the transplanted hearts in the recipients.

”In my opinion, it’s an open-and-shut case. They don’t have irreversibility, and they don’t have death,” said Robert Veatch, a professor of medical ethics at Georgetown University.

But others argue the definition of death is flawed, and that more emphasis should be on informed consent and the chances of survival in cases of severe brain damage.

The Denver transplants were done over three years; one in 2004 and two last year. The three donor infants had all suffered brain damage from lack of oxygen when they were born. On average, they were about four days old when life support was ended.

In the first case, doctors waited for three minutes after the heart stopped before death was declared. Then the waiting time was reduced to 75 seconds on the recommendation of the ethics committee to reduce the chances of damage to the heart.

The authors said 75 seconds was chosen because there had been no known cases of hearts restarting after 60 seconds.

The hearts were given to three babies born with heart defects or heart disease. All three survived, and their outcomes were compared to 17 heart transplants done at the hospital during the same time but from pediatric donors declared brain dead.

”We couldn’t tell the difference,” said Boucek, who’s now at Joe DiMaggio Children’s Hospital in Hollywood, Fla.

There were nine other potential cardiac-death donors at the hospital during the same period, but there wasn’t a suitable recipient in the area for their hearts, the report said.

The parents of one of the infants in the study, Dan Grooms and Jill Airington-Grooms, faced the devastating news on New Year’s Day 2007 that their first child, Addison, had been born with little brain function and wouldn’t survive.

After they decided to remove life support, they were asked about organ donation, and quickly agreed.

”The reality was Addison was not going to live,” said Jill Airington-Grooms. ”As difficult as that was to hear, this opportunity provided us with a ray of hope.”

Three days later, Addison was taken off a ventilator and died. Her heart was given to another Denver-area baby, 2-month-old Zachary Apmann, who was born five weeks premature with an underdeveloped heart.

His parents, Rob and Mary Ann Apmann, said they were given several options and decided to wait for a transplant. They agreed they would accept a cardiac-death donation to increase Zachary’s chances.

Mary Ann Apmann said she wasn’t worried that the first available heart came from a cardiac-death donor.

”At that point, Zachary was so sick. We did have him at home. But we knew it wasn’t much longer,” she said.

After the transplant on Jan. 4, his condition quickly improved, and his blue lips disappeared.

Now, at 21 months: ”He’s just a crazy little kid who loves to play and swim and throw rocks,” his mother said.

The two families haven’t met yet but have been in touch through letters and calls. Coincidentally, Dan Grooms said he had an older brother who died three days after he was born in the 1970s with the same heart condition as Zachary’s. The Grooms now have an 8-month-old daughter, Harper.

”Addison did only live three days in this world, but because of this, she lives on,” her mother said.

------

On the Net:

New England Journal: http://www.nejm.org

UNOS: http://www.unos.org/

NYT ID: 29488626

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共有4条评论
1   [USMedEdu 于 2008-08-20 17:11:29 提到] [FROM: 10.]
发信人: youcc (麦地有喜), 信区: MedicalCareer
标 题: Re: brain death or cardiac death???
发信站: BBS 未名空间站 (Wed Aug 20 17:09:01 2008)



Following definitions may make it more clear.

Donation after brain death
Most of the organs used in transplants come from people who have suffered
brain death as the result of an accident, heart attack, or stroke. Brain
death is total cessation of brain function, including brain stem function.
There is no oxygen or blood flow to the brain; the brain no longer functions
in any manner and will never function again.

The organs and tissues that are in good condition are removed in a surgical
procedure and all incisions are closed so an open casket funeral can take
place. After the organs have been removed, the patient is taken off
artificial support.

While organs must be used between 6 and 72 hours after removal from the
donor's body (depending on the organ), tissues such as corneas, skin, heart
valves, bone, tendons, ligaments, and cartilage can be preserved and stored
in tissue banks for later use.

Donation after cardiac death (DCD)
Some patients that have sustained traumatic brain injury cannot be declared
dead based on the definition of brain death. In these cases, the patient is
declared dead upon cardiac death, which is the cessation of cardiac and
respiratory function when the patient is withdrawn from life support.

Donation after cardiac death occurs only after the patient or family has
decided to withdraw life-sustaining therapies for reasons entirely apart
from any potential for organ donation.

from http://www.organdonor.gov/donation/typesofdonation.htm
 
2   [USMedEdu 于 2008-08-20 11:54:28 提到] [FROM: 10.]
Cardiac Transplantation in Infants

Gregory D. Curfman, M.D., Stephen Morrissey, Ph.D., and Jeffrey M. Drazen, M.D.


http://content.nejm.org/cgi/content/full/359/7/749



For children born with inoperable congenital heart disease or advanced cardiomyopathy, cardiac transplantation is the only therapeutic option. Each year in the United States, approximately 400 heart-transplantation procedures are performed in children and adolescents. In about two thirds, the indication is complex congenital heart disease, and in the remainder it is cardiomyopathy. During the past decade, the procedure has proved lifesaving for thousands of children.

Of the 400 pediatric heart transplantations performed annually, about 100 are in infants under the age of 1 year. The 15-year survival rate among these infants is greater than 50%, increasing to 80% among those who survive for the first 5 years after transplantation. Thus, cardiac transplantation in infants is a highly successful procedure that has saved the lives of many babies with terminal heart disease.

But not all the news is favorable. Each year, as many as 50 infants are placed on the waiting list for cardiac transplantation but die while waiting, owing to the lack of a suitable donor heart. Although in recent years the rate of death among patients awaiting cardiac transplantation has declined in most age groups, the single exception is infants under 1 year of age. Infants in fact have 10 times the risk adults have of dying while waiting for an organ. Thus, a shortage of donor hearts among infants is a serious matter and contributes to a substantial number of otherwise preventable deaths. There is an urgent need for more infant donors, but meeting this need while being mindful of the ethical considerations has been challenging and complex.

According to the "dead donor rule," before donation organ donors must be declared dead, on the basis of either brain-death criteria (i.e., irreversible cessation of all brain functions) or cardiac-death criteria (i.e., irreversible cessation of cardiocirculatory function). Donation after cardiocirculatory death, previously called non-heart-beating donation, typically involves donors who have suffered devastating neurologic injury (yet are not brain dead) but who have normal cardiac function if maintained on life support.

In donation after cardiocirculatory death, life support is withdrawn, the heart stops, death is declared, and organs are then removed for transplantation. To ensure that autoresuscitation (the heart starting again on its own) will not occur, protocols for donation after cardiocirculatory death also require that a suitable period elapse after the cessation of cardiocirculatory function before organs are removed from the donor. The length of that period is a key variable.

A 1997 report from the Institute of Medicine (IOM)1 suggested that 5 minutes should elapse between cardiocirculatory death and organ retrieval, but the report also recommended further study of the validity of this interval. A second IOM report in 20002 reassessed the time interval and stated that "The empirical data available indicate that cardiopulmonary arrest becomes irreversible within a shorter time interval — 60 seconds or less." But the report also stated that "existing empirical data cannot confirm or disprove a specific interval at which the cessation of cardiopulmonary function becomes irreversible," and it concluded that "this is an area in which well-considered judgments continue to differ."

Given these differing judgments, some protocols for donation after cardiocirculatory death have shortened the waiting period after the cessation of cardiocirculatory function to 2 minutes. Although there must be certainty that autoresuscitation will not occur, it is also critical for the benefit of the recipient that the donor organs be protected by minimizing the period of warm ischemia. The 2000 IOM report concluded, "These variations suggest that even with a strong commitment to ethical practice and a reliance on the best clinical data available, there is room for significant differences of opinion on non-heart-beating donation practices."

In this issue of the Journal, Boucek et al.3 report on three successful heart transplantations in infants that involved donation after cardiocirculatory death, a report that is likely to provoke controversy. After informed consent was obtained from the parents and approval granted by the institution's ethics committee, physicians not involved in the transplantation procedures withdrew life support from three prospective infant donors who had sustained severe neurologic injuries but who did not meet brain-death criteria; all had normal cardiac function while receiving life support. The unambiguous separation of the decision to withdraw life support and the decision to donate organs, which is an essential element of all transplantation protocols, rendered this approach acceptable.

After the withdrawal of life support from the three infants, there was cessation of cardiocirculatory activity after an average of 18 minutes. For the first patient, an additional 3 minutes was permitted to elapse before removal of the heart for transplantation was begun. For the other two donors, this interval was shortened to 75 seconds. The basis for the shortened time interval used in this investigational protocol will be questioned by some, but to a certain extent it is consensus, not definitive scientific evidence, that has determined the intervals used. The 2000 IOM report indicated that "it is a decision point at which different options may be followed, but the grounds for selecting one option over another should be clearly specified." In accordance with this requirement, Boucek et al. indicate that the ethics committee recommended "a period of observation of 75 seconds . . . based on the longest reported period before autoresuscitation in a child or adult, 60 seconds."

We are publishing the article by Boucek et al. to foster discussion of donation after cardiocirculatory death in general and its application to infant heart transplantation in particular. To initiate the discussion, in this issue of the Journal we also publish three Perspective articles,4,5,6 along with a video roundtable discussion7 available at www.nejm.org.

In his Perspective article, Veatch4 takes the position that since it was possible to restart the three donor hearts in the recipients after transplantation, there was not irreversible cessation of cardiac function and therefore the criterion for cardiac death had not been met. In his article, Bernat5 points out that the investigational protocol of Boucek et al. tests the permissible boundaries of organ procurement, and he expresses the view that the 75-second interval that they used will ultimately not be found acceptable by the medical community. Truog and Miller6 believe that it is time to reassess the dead donor rule and refocus criteria for organ donation on "valid informed consent under the limited conditions of devastating neurologic injury."

The video roundtable7 was moderated by Atul Gawande, and the panelists were George Annas, Arthur Caplan, and Robert Truog. In this interactive session, they explore a number of ethical issues.

The opinions of each of these experts are controversial and may be challenged. We hope that the articles and roundtable discussion will stimulate debate on organ donation in infants and lead to a consensus that not only meets a high ethical standard but also addresses the urgent shortage of donor organs. The development of standard criteria for pediatric heart donation is a vital goal. In the report by Boucek et al., one conclusion is clear. As a result of their investigational protocol, three babies are now alive; had the procedures not been performed, it is virtually certain that all six babies would be dead.

References


Non-heart-beating organ transplantation: medical and ethical issues in procurement. Washington, DC: National Academy Press, 1997.
Non-heart-beating organ transplantation: practice and protocols. Washington, DC: National Academy Press, 2000.
Boucek MM, Mashburn C, Dunn SM, et al. Pediatric heart transplantation after declaration of cardiocirculatory death. N Engl J Med 2008;359:709-714. [Free Full Text]
Veatch RM. Donating hearts after cardiac death -- reversing the irreversible. N Engl J Med 2008;359:672-673. [Free Full Text]
Bernat JL. The boundaries of organ donation after circulatory death. N Engl J Med 2008;359:669-671. [Free Full Text]
Truog RD, Miller FG. The dead donor rule and organ transplantation. N Engl J Med 2008;359:674-675. [Free Full Text]
Gawande A, Annas GJ, Caplan AL, Truog RD. Organ donation after cardiac death. July 23, 2008. (Available at http://www.nejm.org.)

 
3   [USMedEdu 于 2008-08-20 11:53:31 提到] [FROM: 10.]
Donating Hearts after Cardiac Death — Reversing the Irreversible

Robert M. Veatch, Ph.D.

http://content.nejm.org/cgi/content/full/359/7/672



In this issue of the Journal, Boucek et al. (pages 709–714) report on three cases of heart transplantation from infants who were pronounced dead on the basis of cardiac criteria. The three Perspective articles and a video roundtable discussion at www.nejm.org address key ethical aspects of organ donation after cardiac death. Bernat and Veatch comment on the cases described by Boucek et al.; Truog and Miller raise a fundamental question about the dead donor rule. In a related Perspective roundtable, moderator Atul Gawande, of Harvard Medical School, is joined by George Annas, of the Boston University School of Public Health; Arthur Caplan, of the University of Pennsylvania; and Robert Truog. Watch the roundtable online at www.nejm.org.

Once, all transplantable organs were procured after a donor's heart had stopped irreversibly. Assuming that one accepted the dead donor rule, irreversible heart stoppage triggered organ procurement. Around 1970, the law gradually began to accept the declaration of death on the basis of irreversible loss of brain function. Today, physicians in all U.S. states may pronounce death and procure organs when brain function is determined to be permanently lost. Nevertheless, the more traditional heart-based pronouncement is accepted as an alternative.

The application of either brain- or heart-based criteria for pronouncing death is somewhat more complicated for infants and small children. There is substantial agreement about the measurement of irreversible loss of brain function, so most pediatric organs are obtained after a brain-based pronouncement of death. However, pediatric organs can also be procured after "cardiac death."

Virtually all observers have assumed that donation after cardiac death could, in principle, provide any vital organs except hearts. If someone is pronounced dead on the basis of irreversible loss of heart function, after all, it would not be possible for heart function to be restored in another body. Some have suggested defining death as the impossibility of autoresuscitation, which means that the heart cannot restart spontaneously even if it could be started by means of external stimulation. Calling such a heart "irreversibly stopped" may be defensible if no attempt will be made to restart the heart. However, one cannot say a heart is irreversibly stopped if, in fact, it will be restarted.

In this issue of the Journal, Boucek et al. (pages 709–714) report findings that may seem to address the shortage of hearts for pediatric transplantation. Successful transplantation was performed in three infants with the use of hearts obtained after other, hopelessly ill infants had been pronounced dead according to cardiac criteria. These results appear to open the door to heart transplantation after cardiac death.

A potentially serious question arises, however: when can death be pronounced on the basis of loss of heart function? Death must be permanent. Clinicians sometimes carelessly speak about patients who experience "clinical death" only to be "brought back to life" by means of cardiopulmonary resuscitation. This is, however, an incorrect way of speaking. Death requires the irreversible loss of critical function. For brain death, the irreversible loss of all brain functions is required. There are cases involving hypothermia or depression of the central nervous system in which a patient temporarily experiences a loss of all brain function, only to have that function return. Neurologists insist that such reversible loss be excluded from any definition of death so that death is pronounced only when there is great certainty about the irreversibility of function.

Cardiac death also requires irreversibility. Since procurers of organs cannot legally remove them before the donor's death, they strive to minimize the time between asystole and pronouncement of death. The Pittsburgh protocol for the procurement of organs from adults after cardiac death, published in 1993, specified that asystole last 120 seconds, on the basis of the claim that autoresuscitation had never occurred after that period.1

Physiologically, however, a heart could be restarted after a period of 120 seconds by means of external stimulation — a fact that has led to extensive debate over the meaning of "irreversible loss of function." Some experts have insisted that one wait until the heart cannot be restarted to pronounce death, a number of them pressing for waiting times of 10 minutes or longer. The Institute of Medicine has proposed waiting for 5 minutes.2

Other experts have argued for shorter times — as short as the 120 seconds of the Pittsburgh protocol for adults. They have argued that in cases in which a withdrawal of life support has been planned, no one will intervene to restart the heart, and therefore the stoppage is "irreversible"; a heart cannot legally be restarted if resuscitation has been refused, so its loss of function, these observers claim, meets one definition of irreversibility. Clearly, the requirement that the heart will not be restarted in such cases is crucial to this argument. Otherwise, anyone who had had a cardiac arrest lasting beyond the time at which autoresuscitation was possible would be legally deceased, even if the heart had been successfully restarted through external stimulation.

The practice of donation after cardiac death has gained some acceptance, but only for organs other than hearts. There are controversial implications, however, if the goal is to transplant a heart after cardiac death. It is impossible to transplant a heart successfully after irreversible stoppage: if a heart is restarted, the person from whom it was taken cannot have been dead according to cardiac criteria. Removing organs from a patient whose heart not only can be restarted, but also has been or will be restarted in another body, is ending a life by organ removal. Of course, it would still be possible to pronounce such patients dead if they met the criteria for brain death, but according to this logic, it would simply not be possible to perform successful heart transplantation in a manner consistent with the dead donor rule after death pronounced on the basis of cardiac criteria.

This means that under current law, it is not possible to procure a transplantable heart after cardiac death. There are two possible ways out of this dilemma. Both involve legal changes.

First, we could change the law to permit the removal of vital organs while a donor was still alive — a solution that has essentially been proposed by some theorists, including Truog and Miller (pages 674–675).3,4 Such removals would have to be limited. Presumably, they could occur in terminally ill patients who were dying rapidly, and probably only in those who had consented to having their lives end through organ removal.

I believe that such proposals for exceptions to the dead donor rule are practically and morally implausible. Practically speaking, it seems unlikely that sufficient political support will ever exist for removing vital organs from living people, even those who are near death. Many would argue that the very meaning of being alive in a moral community entails certain individual rights, arguably including the right not to have one's life ended by organ removal.

This implausibility of creating exceptions to the dead donor rule suggests a second possible approach. We could further amend the definition of death so that the total loss of those brain functions that are responsible for consciousness would be the basis for pronouncing death. This proposal, sometimes called the higher-brain definition and first put forth in 1971, would permit limited use of a brain-based pronouncement of death and heart procurement in the absence of irreversible heart stoppage.

It is not clear whether further redefinition is in order. Surely, definitions should not be changed simply to make hearts available, but many Americans — perhaps as many as a third of the population — already support this higher-brain, or consciousness-based, definition on religious and philosophical grounds. A good case can be made for letting those whose values support such a definition choose to have it applied to them.5 Perhaps we could also give parents and other surrogates the option to choose this higher-brain definition for their wards.

It may ultimately be deemed acceptable to amend either the dead donor rule or the brain-based definition of death. But whether or not any such legal changes come to pass, any successfully transplanted heart cannot have come from a person who was declared dead on the basis of irreversible stoppage of the heart.

No potential conflict of interest relevant to this article was reported.


Source Information

Dr. Veatch is a professor of medical ethics at the Kennedy Institute of Ethics, Georgetown University, Washington, DC.

References


University of Pittsburgh Medical Center policy and procedure manual: management of terminally ill patients who may become organ donors after death. Kennedy Inst Ethics J 1993;3:A1-A15. [Medline]
Non-heart-beating organ transplantation: medical and ethical issues in procurement. Washington, DC: National Academy Press, 1997.
Koppelman ER. The dead donor rule and the concept of death: severing the ties that bind them. Am J Bioeth 2003;3:1-9. [ISI][Medline]
Truog RD, Robinson WM. Role of brain death and the dead-donor rule in the ethics of organ transplantation. Crit Care Med 2003;31:2391-2396. [CrossRef][ISI][Medline]
The conscience clause: how much individual choice in defining death can our society tolerate? In: Youngner SJ, Arnold RM, Schapiro R, eds. The definition of death: contemporary controversies. Baltimore: Johns Hopkins University Press, 1999:137-60.
 
4   [USMedEdu 于 2008-08-20 11:52:22 提到] [FROM: 10.]
The Dead Donor Rule and Organ Transplantation

http://content.nejm.org/cgi/content/full/359/7/674


Robert D. Truog, M.D., and Franklin G. Miller, Ph.D.


In this issue of the Journal, Boucek et al. (pages 709–714) report on three cases of heart transplantation from infants who were pronounced dead on the basis of cardiac criteria. The three Perspective articles and a video roundtable discussion at www.nejm.org address key ethical aspects of organ donation after cardiac death. Bernat and Veatch comment on the cases described by Boucek et al.; Truog and Miller raise a fundamental question about the dead donor rule. In a related Perspective roundtable, moderator Atul Gawande, of Harvard Medical School, is joined by George Annas, of the Boston University School of Public Health; Arthur Caplan, of the University of Pennsylvania; and Robert Truog. Watch the roundtable online at www.nejm.org.

Since its inception, organ transplantation has been guided by the overarching ethical requirement known as the dead donor rule, which simply states that patients must be declared dead before the removal of any vital organs for transplantation. Before the development of modern critical care, the diagnosis of death was relatively straightforward: patients were dead when they were cold, blue, and stiff. Unfortunately, organs from these traditional cadavers cannot be used for transplantation. Forty years ago, an ad hoc committee at Harvard Medical School, chaired by Henry Beecher, suggested revising the definition of death in a way that would make some patients with devastating neurologic injury suitable for organ transplantation under the dead donor rule.1

The concept of brain death has served us well and has been the ethical and legal justification for thousands of lifesaving donations and transplantations. Even so, there have been persistent questions about whether patients with massive brain injury, apnea, and loss of brain-stem reflexes are really dead. After all, when the injury is entirely intracranial, these patients look very much alive: they are warm and pink; they digest and metabolize food, excrete waste, undergo sexual maturation, and can even reproduce. To a casual observer, they look just like patients who are receiving long-term artificial ventilation and are asleep.

The arguments about why these patients should be considered dead have never been fully convincing. The definition of brain death requires the complete absence of all functions of the entire brain, yet many of these patients retain essential neurologic function, such as the regulated secretion of hypothalamic hormones.2 Some have argued that these patients are dead because they are permanently unconscious (which is true), but if this is the justification, then patients in a permanent vegetative state, who breathe spontaneously, should also be diagnosed as dead, a characterization that most regard as implausible. Others have claimed that "brain-dead" patients are dead because their brain damage has led to the "permanent cessation of functioning of the organism as a whole."3 Yet evidence shows that if these patients are supported beyond the acute phase of their illness (which is rarely done), they can survive for many years.4 The uncomfortable conclusion to be drawn from this literature is that although it may be perfectly ethical to remove vital organs for transplantation from patients who satisfy the diagnostic criteria of brain death, the reason it is ethical cannot be that we are convinced they are really dead.

Over the past few years, our reliance on the dead donor rule has again been challenged, this time by the emergence of donation after cardiac death as a pathway for organ donation. Under protocols for this type of donation, patients who are not brain-dead but who are undergoing an orchestrated withdrawal of life support are monitored for the onset of cardiac arrest. In typical protocols, patients are pronounced dead 2 to 5 minutes after the onset of asystole (on the basis of cardiac criteria), and their organs are expeditiously removed for transplantation. Although everyone agrees that many patients could be resuscitated after an interval of 2 to 5 minutes, advocates of this approach to donation say that these patients can be regarded as dead because a decision has been made not to attempt resuscitation.

This understanding of death is problematic at several levels. The cardiac definition of death requires the irreversible cessation of cardiac function. Whereas the common understanding of "irreversible" is "impossible to reverse," in this context irreversibility is interpreted as the result of a choice not to reverse. This interpretation creates the paradox that the hearts of patients who have been declared dead on the basis of the irreversible loss of cardiac function have in fact been transplanted and have successfully functioned in the chest of another. Again, although it may be ethical to remove vital organs from these patients, we believe that the reason it is ethical cannot convincingly be that the donors are dead.

At the dawn of organ transplantation, the dead donor rule was accepted as an ethical premise that did not require reflection or justification, presumably because it appeared to be necessary as a safeguard against the unethical removal of vital organs from vulnerable patients. In retrospect, however, it appears that reliance on the dead donor rule has greater potential to undermine trust in the transplantation enterprise than to preserve it. At worst, this ongoing reliance suggests that the medical profession has been gerrymandering the definition of death to carefully conform with conditions that are most favorable for transplantation. At best, the rule has provided misleading ethical cover that cannot withstand careful scrutiny. A better approach to procuring vital organs while protecting vulnerable patients against abuse would be to emphasize the importance of obtaining valid informed consent for organ donation from patients or surrogates before the withdrawal of life-sustaining treatment in situations of devastating and irreversible neurologic injury.5

What has been the cost of our continued dependence on the dead donor rule? In addition to fostering conceptual confusion about the ethical requirements of organ donation, it has compromised the goals of transplantation for donors and recipients alike. By requiring organ donors to meet flawed definitions of death before organ procurement, we deny patients and their families the opportunity to donate organs if the patients have devastating, irreversible neurologic injuries that do not meet the technical requirements of brain death. In the case of donation after cardiac death, the ischemia time inherent in the donation process necessarily diminishes the value of the transplants by reducing both the quantity and the quality of the organs that can be procured.

Many will object that transplantation surgeons cannot legally or ethically remove vital organs from patients before death, since doing so will cause their death. However, if the critiques of the current methods of diagnosing death are correct, then such actions are already taking place on a routine basis. Moreover, in modern intensive care units, ethically justified decisions and actions of physicians are already the proximate cause of death for many patients — for instance, when mechanical ventilation is withdrawn. Whether death occurs as the result of ventilator withdrawal or organ procurement, the ethically relevant precondition is valid consent by the patient or surrogate. With such consent, there is no harm or wrong done in retrieving vital organs before death, provided that anesthesia is administered. With proper safeguards, no patient will die from vital organ donation who would not otherwise die as a result of the withdrawal of life support. Finally, surveys suggest that issues related to respect for valid consent and the degree of neurologic injury may be more important to the public than concerns about whether the patient is already dead at the time the organs are removed.

In sum, as an ethical requirement for organ donation, the dead donor rule has required unnecessary and unsupportable revisions of the definition of death. Characterizing the ethical requirements of organ donation in terms of valid informed consent under the limited conditions of devastating neurologic injury is ethically sound, optimally respects the desires of those who wish to donate organs, and has the potential to maximize the number and quality of organs available to those in need.

No potential conflict of interest relevant to this article was reported.

The opinions expressed in this article are those of the authors and do not necessarily reflect the policy of the National Institutes of Health, the Public Health Service, or the Department of Health and Human Services.


Source Information

Dr. Truog is a professor of medical ethics and anesthesia (pediatrics) in the Departments of Anesthesia and Social Medicine at Harvard Medical School and the Division of Critical Care Medicine at Children's Hospital Boston — both in Boston. Dr. Miller is a faculty member in the Department of Bioethics, National Institutes of Health, Bethesda, MD.

References


A definition of irreversible coma: report of the ad hoc committee of the Harvard Medical School to examine the definition of brain death. JAMA 1968;205:337-340. [CrossRef][Medline]
Truog RD. Is it time to abandon brain death? Hastings Cent Rep 1997;27:29-37. [ISI][Medline]
Bernat JL, Culver CM, Gert B. On the definition and criterion of death. Ann Intern Med 1981;94:389-394. [CrossRef][ISI][Medline]
Shewmon DA. Chronic "brain death": meta-analysis and conceptual consequences. Neurology 1998;51:1538-1545. [Free Full Text]
Miller FG, Truog RD. Rethinking the ethics of vital organ donation. Hastings Cent Rep (in press).
 
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