Brain Death

Understanding Brain Death Of all the people who die in India each year, relatively few die under circumstances that make them medically eligible to be organ donors. To understand organ donation and the shortage of organs for transplants, one needs to have a basic understanding of brain death and what impact it has on whether they can, in fact, be donors or not.

Brain Death and Organ Donation

The general idea of death is that it occurs when the heart stops beating and breathing ceases.

When brain death occurs it is different. Though there is irreversible loss of all brain function and the patient is clinically and legally dead, the appearance of life continues. This is only because of a breathing machine (ventilator), which is an artificial means for delivering enough oxygen to the heart to keep it beating. Through this mechanism, the heart, lung, liver, kidney and pancreas can be kept alive for a few hours.

Brain death can be confusing, particularly for families who are confronted with the sudden death of  their dear ones because a brain dead person on a ventilator  can look "alive", as their  heart is still beating and the ventilator is pumping oxygen and air into the lungs making the person's chest rise and fall.
This makes some families expect that if their loved ones are continuously kept on ventilator they will progress. But the truth is, brain dead is to be dead, and no recovery is possible. There is no method to revive a brain that has been deprived of blood and whose cells have died.

How does brain death occur?

Brain death can occur in patients who have sustained injuries to the brain resulting from traumatic causes such as  road accidents,  falls, blows to the head -- and non-traumatic causes like  spontaneous bleeding from high blood pressure or bursting of brain aneurysm, drowning, and carbonmonoxide poisoning  during which time the brain is deprived of blood and oxygen. A head trauma or bleeding in the brain will cause the brain tissue to swell.  The action of the brain swelling inside a closed space and the build-up of pressure is what can ultimately lead to brain death. As the brain swells inside the skull, it pushes downward toward the brain stem blocking all upward flow of blood. Depending on the type of injury, this may happen within minutes or over a period of days. Even while the heart is still beating and supplying blood to the rest of the body, blood that carries oxygen cannot reach the brain or the brain stem, which controls heart rate and breathing. The result is that the brain and the person die.

What is the difference between coma and brain death?

A patient in coma is not dead.
Unlike a brain dead person, the brain waves and brain stem functions are active and the body is able to maintain vital functions such as regulating the temperature, blood pressure and respiration.

Whereas, in the case of brain death the person has no brain waves and no brain stem function; therefore the inability to manage body functions. The organs can be kept alive for a few hours with mechanical assistance.