Living Donor
Directed Donation
Organs are allocated by a national system overseen by the federal government and
administered by the United Network for Organ Sharing (UNOS). Organs are allocated
in a fair manner so as to not discriminate against anyone due to race, wealth or
celebrity status. There is an occasional situation when donor families know another
family member or friend that is awaiting organ transplantation. The family can elect
to "direct the donation" to that individual. This "directed donation"
is carried out if the organ is of compatible size and blood type and is also accepted
by the transplant center where the patient is listed.
Deceased Donor
To qualify as a deceased donor, you must meet brain death criteria
What is brain death?
Brain death occurs when a person has an irreversible, catastrophic brain injury,
which causes total cessation of all brain function (the upper brain structure and
brain stem). Brain death is not a coma or persistent vegetative state. A physician
not associated with the transplantation team determines brain death.
Brain death occurs when blood and the oxygen it carries cannot flow to the brain.
Without blood and oxygen, the brain dies. When the brain dies, the person cannot
move, breathe, think or feel. Pain and suffering ceases. The heart can continue
to beat for awhile as the ventilator (breathing machine) provides artificial support
and oxygen to the body. It may look like the person is sleeping because the ventilator
fills the lungs with oxygen and helps keep the skin pink and warm. They are not
sleeping. Brain death is death and cannot be reversed.
There are two ways of defining death. One is brain death, meaning the brain has
stopped working and will never recover. This is different from coma, which is when
someone is unconscious because of brain injury, but the brain still works and may
heal eventually. The other definition of death is when the heart has stopped forever.
This is called cardiopulmonary death.
How can brain death be determined?
Clinical Exam - First, the absence of function of all parts of the brain, as determined
by clinical assessment (no movement, no response to stimulation, no breathing, no
brain reflexes.)
Confirmatory Tests - Next, there is no electrical activity in the brain; this is
determined by an EEG. Finally, there is no blood flow to the brain; this is determined
by cerebral blood flow studies.
There are several ways in which a person can become brain dead, these include:
Anoxia - caused by drowning, respiratory diseases or drug overdose.
Ischemia - blockage of an artery leading to the brain or in the brain, heart attack
(stoppage of the heart for a period of time), bleeding in the brain.
Intracranial hemmorrhage - caused by a head injury (a blow to the head) or a ruptured
aneurysm. The ballooning of a blood vessel supplying the brain - can cut off blood
supply or rupture.
A gunshot wound to the head - causes destruction of brain tissue and swelling of
the brain.
Brain tumors - can destroy brain tissue and increase pressure within the brain,
but do not go outside the central nervous system so organs are not affected.
When any of the above occur, they cause swelling of the brain. Because the brain
is enclosed in the skull, it does not have room to swell, thus pressure within the
skull increases (this is "intracranial pressure"). This can stop blood
flow to the brain; killing brain cells and causing herniation of the brain (pushing
the brain outside of its normal space). When brain cells die, they do not grow back,
thus any damage caused is permanent and irreversible.
Some points to note:
- A person's heart can still be beating because of the ventilator and medications
helping to keep the blood pressure normal.
- A person who is declared brain dead by brain death criteria is legally dead.