national conference on organ donation after cardiac
death (DCD) was convened in Philadelphia, Pennsylvania,
on April 7-8, 2005, with the goals of sharing DCD
experience and garnering a consensus on the medical
and ethical propriety of organ donation after cardiac
death. Conference participants represented a broad
spectrum of health care professionals, including
transplant specialists, critical care intensivists,
neuroscientists and ethicists. Six working groups
were assembled to deliberate on specific DCD issues
and fulfill the conference objectives: 1) to define
cardiopulmonary criteria for the determination of
death, 2) to establish predictive criteria for circulatory
arrest within one hour of withdrawal of donor life
support, 3) to establish protocols for DCD organ
recovery (kidney, liver, pancreas and lung) and
transplantation, 4) to develop strategies to initiate
and increase DCD in donation service areas, 5) to
discuss the allocation of DCD organs for transplantation
and 6) to examine perceptions of DCD held by the
media and the public.
As a representative of the ASA Committee on Transplant
Anesthesia with 20 years of experience as a liver
transplant anesthesiologist and a recognized expert
in donor management, I was invited to serve as a
member of the Executive Committee and participate
in Group 3, led by Tony D’Alessandro, M.D.,
and Bob Gaston, M.D. A complete summary of the discussion,
findings, recommendations and list of participants
in each group has been published (Am J Transplantation.
2006; 6:281-291).
Given that DCD is an evolving science in the field
of transplant medicine, anesthesiologists should
be positive, knowledgeable and informed of the major
practical and ethical issues surrounding DCD and
organ retrieval.
Practical Issues
Most anesthesiologists are confused about their
role in DCD and have legitimate concerns regarding
participation. Typically withdrawal of intensive
care support and extubation of these donors occurs
in the operating room (O.R.), followed by an observation
period of up to two hours during which time the
criteria for cardiac death must be met (absence
of responsiveness, heart sounds, pulse and respiratory
effort). After circulatory cessation and a waiting
period that varies (at least two minutes of observation,
with more than five minutes not recommended), declaration
of death is then made by a physician who is not
a member of the surgical or anesthetic care team.
The transplant surgeons will then initiate cold
flushing of the organs with preservation solution
and proceed with the donor operation. As the lungs
require re-inflation before retrieval, the anesthesiologist
may be asked by the surgical team to re-intubate
the donor or to provide patient care during a bronchoscopy,
which is necessary to assess suitability of the
lungs for donation prior to withdrawal of support.
It is important that anesthesiologists are familiar
with their institutional DCD protocol and the following
key points:
• The care of DCD patients
should not be transferred to anesthesiologists
in the O.R. for withdrawal of life support. Provision
of quality end-of-life care for patients and their
families is the absolute priority of care and
must not be compromised by the donation process.
Managing withdrawal of nonbeneficial treatments
is not within the expertise or practice of all
anesthesiologists, and as such, continuity of
care for patients presenting for DCD optimally
should be provided by the donor patient’s
own physician.
• Determination of death is made using cardiopulmonary
criterion (for DCD), which does not require evidence
of irreversible brain injury (for donation after
brain death, or DBD).
• We should be respectful of the wishes
of donor patients, their families and their physicians
when they are in the O.R. setting.
• Anesthesiologists should have an active
role in the formation of DCD protocols within
their own hospitals for the provision of ethical
terminal care for living donors and their families.
Increasing the donor pool is crucial
for providing a sufficient number of organs to accommodate
the more than 90,000 patients currently wait-listed
for transplantation in the United States. As such
the U.S. Department of Health and Human Services
recently initiated the Organ Donation Breakthrough
Collaborative in a strategic attempt to establish
organ donation best practices and implement highly
effective organ donation systems nationwide. Since
2002 the total number of deceased donors has increased
from 6,190 to 7,152 (2004) as a result of an increase
in the total number of brain-dead donors and an
acceleration in DCD organ recovery.
Prior to 1999, there were 345 DCD, of which more
than 98 percent were kidney donors. From 1999-2004,
the total number of DCD increased to 1,224, with
the most dramatic increase from 270 cases in 2003
to 391 cases in 2004 (Organ Procurement and Transplantation
Network/Scientific Registry of Transplant Recipients
Annual Report 2005). DCD now accounts for more than
5 percent of all deceased organ donors. Approximately
79 percent of all intra-abdominal organs recovered
from DCD donors are transplanted, which compares
favorably with non-DCD (89 percent). Current data
show equivalency in graft and patient survivals
of DCD and DBD primary kidney transplants despite
higher delayed graft function rates in DCD organs.
The risk of graft failure for DCD livers is higher
compared with non-DCD livers (relative risk, 1.85).
Ethical Dilemmas Resolved
Efforts to increase organ donation have been met
with resistance from anesthesiologists who are concerned
about being coerced into morally, legally and professionally
compromising situations. The major ethical issues
in DCD organ donation and procurement are held in
the balance between the doctrines of beneficence
(doing good for the patient and society as a whole)
and nonmaleficence (do no harm). This national
conference overwhelmingly affirmed the ethical propriety
of DCD as not violating the dead-donor rule in that
the retrieval of organs for transplantation does
not cause the death of a donor. A prospective organ
donor’s death may now be determined by either
cardiopulmonary (DCD) or neurologic criteria (DBD).
Based on a cardiopulmonary criterion, DCD donor
death occurs when respiration and circulation have
ceased and cardiopulmonary function will not resume
spontaneously.
Protocols for DCD organ recovery routinely include
the prerecovery administration of anticoagulants,
vasodilators and drugs designed to minimize ischemia-reperfusion
injury. The issue that remains unresolved concerns
timing of administration. In addition it is mandatory
that drug therapy must not hasten the death of the
donor unless there is a direct benefit to the patient
(double effect). An example of this would be administration
of opiates for pain relief, which has the inherent
risk of respiratory depression. Rapid core cooling
of perfusable organs is essential to limit the warm
ischemic insult, but informed consent of the patient
or family is necessary for any premortem cannulation
of large arteries and veins or other interventions
(i.e., extracorporeal membrane oxygenation or chest
incision for open cardiac massage). As the risk
of graft failure is greater for DCD livers, recipients
will be asked if they are willing to accept DCD
liver offers. Obtaining final consent for transplant
should include a discussion of transplantation of
organs from donors with varying degrees of risk
of failure versus the mortality risk of waiting
for the next available ideal donor.
The National Conference on Donation After Cardiac
Death affirmed DCD as an ethically acceptable practice
of end-of-life care capable of increasing the number
of deceased-donor organs available for successful
transplantation. The public message to be conveyed
is that DCD honors donor wishes in the continuum
of quality end-of-life care, it can provide comfort
and support to donor families, and it saves lives.
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Kerri M. Robertson, M.D., F.R.C.P. (C), is Associate
Clinical Professor, Chief of General, Vascular,
High-Risk, Trauma, Transplant and Surgical Critical
Care Medicine, Chief of Transplant Services,
Department of Anesthesiology, Duke University
Medical Center, Durham, North Carolina. |
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