The diagnosis of brain death is defined as "death based on the absence of all neurologic function." Families who have had a loved one declared brain dead may have questions about what the term really means.
What does "brain death" mean?
Brain death is a legal definition of death. It is the complete and irreversible cessation (stopping) of all brain function. It means that, as a result of severe trauma or injury to the brain, the body's blood supply to the brain is blocked, and the brain dies. Brain death is death. It is permanent and irreversible.
How is it decided that an individual is brain dead?
A physician conducts the required medical tests to make the diagnosis of brain death. These tests are based on sound and legally accepted medical guidelines. Among other things, tests include a clinical examination to show that an individual has no brain reflexes and cannot breathe on his or her own.
In some situations, other testing may be needed. You can ask your doctor to explain or show you how brain death was determined for your loved one.
Possibly, an individual may exhibit spinal activity or reflexes such as twitching or muscle contractions. Spinal reflexes are caused by electrical impulses that remain in the spinal column. These reflexes may occur even though the brain is dead.
What happens to an individual while these tests are being done?
The individual is placed on a machine that breathes for him or her, called a ventilator, because the brain can no longer send signals telling the body to breathe. Special medications to help maintain blood pressure and other body functions may also be given.
During the brain death testing, the ventilator and medications continue but they do not interfere with the brain death determination.
Aren't there drugs that can stop the brain from working and give a false diagnosis?
Certain drugs can mask brain function, such as muscle relaxants and sedatives. When the tests are performed, the individual can only have low levels of these drugs in the body. It may be necessary to wait for these levels to go down. The physician can then accurately measure brain activity. Often other tests are done to confirm brain death if certain drugs are present in the body.
If brain death is confirmed, why does an individual's heart continue beating?
As long as the heart has oxygen, it can continue to work. The ventilator provides enough oxygen to keep the heart beating for several hours. Without this artificial help, the heart would stop beating.
Is it possible that an individual is in a coma?
No. A patient in a coma continues to have brain activity and function. When brain death occurs, all brain function ceases and there is no chance of recovery.
Is there anything else that can be done?
Before brain death is declared, everything possible to save an individual's life is done. After the diagnosis of brain death is made there is no chance of recovery.
The individual may appear to be only sleeping. The ventilator fills the lungs with air. The heart monitors may indicate that the heart is sill beating. The individual's body may be warm to the touch and there may still be color in his or her face. But, in fact, the individual is dead.
What happens when an individual is declared brain dead?
Once the diagnosis of brain death is made, an individual is pronounced legally dead. This is the time that should appear on the death certificate. The time of death is not the time when the ventilator is removed.
Does an individual feel any pain or suffer after brain death is declared?
No. When someone is dead, there is no feeling of pain or suffering.
After brain death is declared, what happens next?
In many cases brain death results from a sudden accident or injury. A health care professional will talk with you about certain decisions you need to make at this time. Among those decisions could be removing the ventilator and the possibility of organ and/or tissue donation.
Remember, the individual is already legally dead and removing the ventilator does not cause death.
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© 2014 National Kidney Foundation. All rights reserved. This material does not constitute medical advice. It is intended for informational purposes only. Please consult a physician for specific treatment recommendations.