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DEFINING DEATH. Rels 300 / Nurs 330 April 2014. Cardiopulmonary Death Whole Brain Death Higher Brain Death Non-heart-beating Death. Why do we need a definition of death?. To provide answers to questions such as these:
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DEFINING DEATH Rels 300 / Nurs 330 April 2014
Cardiopulmonary Death • Whole Brain Death • Higher Brain Death • Non-heart-beating Death 300/330 - appleby
Why do we need a definition of death? To provide answers to questions such as these: • When is it appropriate to cease treatment or disconnect life-sustaining treatment? • How would one know if the person has died from a disease process or was killed? • When is it permissible to retrieve organs or tissues from a person’s body? • When is it appropriate to initiate the process of preparing a person’s body for burial? 300/330 - appleby
1. Cardiopulmonary Death • A person is dead when spontaneous heart function has ceased, and • the person is no longer breathing, and • there is no longer any blood pressure • Nothing chemical or mechanical is blocking heart or respiratory function, and • There is no further intervention which is determined to be appropriate in this person’s situation. 300/330 - appleby
Cardiopulmonary death criteria • University of Alberta’s director of critical care, Dr. David Zygun, says “death is a process, and when it’s a process, taking it to one specific time is very difficult” Donation after cardiac death was the only method of deceased organ donation prior to the advent of brain death criteria in the 1960s — when the concept of someone being "brain dead" was first introduced. • Canadian national guidelines for pronouncing cardiac death for organ donation require doctors to wait at least five minutes after the heart stops beating. • Toronto’s Sunnybrook Hospital – 5 minutes; Toronto General Hospital – 5 minutes; St. Michael’s Hospital – 10 minutes • Edmonton’s Dr. Ari Joffe argues that it would take at least 20 or 30 minutes to be sure death is irreversible 300/330 - appleby
Sarah Beth Therien In 2006, Sarah Beth “became the first Canadian in nearly four decades to donate her organs after cardiac death, fulfilling her final wish, her parents say.” Donation after cardiac death could increase the number of available organs by 10 to 30 per cent, according to experts. 300/330 - appleby
2. Whole Brain Death • 1968 Ad Hoc Committee of the Harvard Medical School was established to examine the existing definition of death WHY? • After death is certain according to cardiopulmonary criteria, most organs have deteriorated to the point of being unusable • Comatose patients may continue to live almost indefinitely with mechanical ventilators and artificial feeding 300/330 - appleby
Committee’s Report • A person may be declared to be dead when the entire brain, including the brainstem, has ceased to function and this condition is irreversible • Cessation of spontaneous respiration is a reliable indicator that brainstem function is absent; other indicators include pupils which do not react to light, and absence of spinal reflexes 300/330 - appleby
Brain Death Exclusions • Drug intoxication • Hypothermia • Reversible causes of cerebral dysfunction After a continuous period of 24 hours in which evidence of brain function is absent, and possible reversible causes of brain dysfunction have been ruled out, a person may be determined to be dead. 300/330 - appleby
Canadian Neurocritical Care Group 1999Guidelines for the Diagnosis of Brain Death “Brain death is defined as the irreversible loss of the capacity for consciousness combined with the irreversible loss of all brainstem functions including the capacity to breathe. “Brain death is equivalent to death of the individual, even though the heart continues to beat and spinal cord functions may persist.” Canadian Journal of Neurological Sciences 1999; 26:64-66 300/330 - appleby
CNGC 1999 Guidelines • An etiology has been established that is capable of causing brain death; potentially reversible causes have been excluded • The patient is in deep coma and shows no response to stimulation of any part of the body • Brain stem reflexes are absent • The patient is apneic when taken off the respirator for an appropriate time (8 to 10 minutes) • The conditions listed above persist when the patient is reassessed after a suitable interval (2 to 24 hours) • There should be no confounding factors for the application of clinical criteria 300/330 - appleby
3. Higher Brain Death • “One is dead when there is irreversible loss of all ‘higher’ brain functions.” Veatch as quoted in our text, p.217 • Death has occurred when there is an irreversible loss of all cognitive brain function • The brainstem may still be functioning, as evidenced by spontaneous breathing and heartbeat • But the person has permanently lost the capacity for consciousness (i.e., the “higher” brain) 300/330 - appleby
Why move to a “higher” brain definition of death? • Shortage of organs and tissues for transplantation • Desire to increase the size of the donor pool What new groups of patients would become eligible as potential donors? 300/330 - appleby
4. Non-heart-beating Donors • A person who has been diagnosed as brain dead, but is still on a respirator, continues to breathe and have a heart beat • Other persons who are dying, but are not brain dead, may wish to donate organs after withdrawal of life-sustaining interventions • Competent patients who are dying may request that life-sustaining treatments be withdrawn, even if death will result • Surrogate decision makers may make this same request on behalf of incompetent patients if such a request reflects the wishes of the previously competent person, or if treatment is futile, or if the patient has unrelievable pain or suffering 300/330 - appleby
The Pittsburgh Protocol “After an elaborate informed-consent process, the patient is taken to the operating room … prepped for surgery, and the ventilator turned off. Two minutes after the heart stops beating, the surgeons come in and remove the organs as quickly as possible to reduce warm ischemia time.” Youngner as quoted in our text, p.251 300/330 - appleby
Is there an inevitable “next step”? • P. 253, Younger “If we ask patients, as the Pittsburgh protocol does, to become donors when they ask that their ventilators be turned off, why would we not allow them the same prerogative when we help them to commit suicide [assisted suicide] or put them to death at their own request [euthanasia] ?” • Have we, as Renee Fox says, “lost the reverent respect for the dignity of human life and death that ought to undergird these acts”? (p.253) 300/330 - appleby