What being declared ‘brain dead’ means
By Joel Masibo, October 7, 2025You may have heard the medical terminology ‘brain dead’ on one or two occasions, but have you ever wanted to have a deeper understanding of what being declared ‘brain dead’ means in the field of medicine?
Being declared brain dead is one of the most serious diagnoses in medicine. While it is often misunderstood and sometimes confused with a coma or a vegetative state, brain death has a precise medical and legal meaning.
Meaning of brain dead
This is a health condition that marks the irreversible loss of all brain function, including the brainstem, which controls vital reflexes such as breathing and heartbeat regulation.
This occurs when the brain is so severely damaged that it can no longer send or receive signals necessary for sustaining life. This damage can result from traumatic injuries to the head, massive strokes, severe oxygen deprivation (such as after cardiac arrest), or brain infections that cause swelling and destruction of brain tissue.
When a person is brain dead, their brain has permanently stopped working, even though machines like ventilators may keep their heart beating and maintain oxygen flow to other organs. Unlike someone in a coma, who may still have minimal brain activity, there is no possibility of recovery once brain death is confirmed.
Cleveland Clinic, in its research on the topic, says; ”In brain death, injury or illness does severe, permanent damage to your entire brain and brainstem. Your brainstem manages your breathing and heart rate. Your brain manages senses like sight, sound and touch, and abilities like motor movement,” the statement reads in part.
Differences between coma and brain death
The medical institution, the Cleveland Clinic, further explains the existing differences between being in a coma and being declared brain dead.
”If you’re in a coma, you’re unconscious, but you have some reflex response. For example, you might blink or turn your head when someone shines a bright light in your eyes. In brain death, you don’t have reflex responses.”
“Likewise, comas aren’t always permanent. Most people emerge from comas within two weeks. In brain death, a person never regains consciousness due to permanent loss of brain function, which is completely irreversible,” the statement adds.
In most countries, including Kenya, brain death is legally recognised as death. Once brain death is declared, the patient is considered deceased even if machines are keeping their heart beating.