What is Brain Death

What is Brain Death?

Brain Death is when an irreversible and complete loss of brain and brain stem function has taken place. This means that there is absolutely no brain activity and brain activity will not return.

It is considered both a legal and medical definition of death.

At this point, the patient is incapable of surviving without mechanical support.

You can see the difference of a brain with blood flow and brain activity, and one that is without any function.

Normal Brain to compare to what brain death looks like.The above image shows the blood flow inside a normal, active brain. When someone severely injures their brain, the blood flow is cut off or restricted by pressure from the swelling brain.
A picture of what brain death looks like in the brain. Brain death occurs when the blood flow to the brain is entirely lost. The photo above is of a brain dead brain. (Images courtesy of Gift of a Lifetime, www.organtransplants.org)

How does Brain Death Happen?

It typically occurs after a major injury or illness where the blood supply to the brain is blocked or the brain begins to swell within the skull.

This can be a traumatic head injury, a stroke, or the heart stopping for a prolonged period. These traumatic events cause the brain to lose oxygen, lose blood, or begin to swell beyond recovery.

How is Someone Declared Brain Dead?

In California, two separate doctors will independently run a series of standardized exams that test whether or not the brain is functioning at any level.

If both doctors find the patient absent of any responses, the patient is then declared dead. This is the point when the time of death takes place.

Can You Recover from Brain Death?

No, a patient who is brain dead will not be able to recover. The body may continue to breathe with mechanical support but eventually, both the breathing and heart will stop even with continued support.

Being brain dead is not the same as being in a coma or a prolonged vegetative state. The latter two are medical states where one may be unconscious but still show brain function.

The media and Hollywood often use these terms interchangeably. But both medically and legally, brain death is its own distinguishable diagnosis that one cannot recover from.

How is Brain Death Related to Organ Donation?

In order to be medically able to become an organ donor, an individual must pass away on a ventilator in a hospital. While being brain dead is not the only way this can happen, it is the most frequent condition of those who become organ donors.

Only after someone has been declared brain dead, legally dead, the hospital will contact the local organ procurement organization to begin the consideration of donation. Not until this point is it looked up to see if someone is registered as a donor and/or the family is approached to be asked if they would like their loved one to be a donor.

Once a legal record of donor registration is found and/or a family has consent then the organ donation process will begin. If someone is not a registered donor and the family does not consent the person will not become a donor.

Learn more about how the donation process works from start to finish here.