Coma is a deep state of unconsciousness. People will not react to painful stimuli, etc. They are not dead and there is minimal brain activity. They may or may not recover from being in a coma.
A stroke (in the brain) is a failure of the circulatory system to provide oxygen to the brain. It can be caused by either a blockage (ischemic) or bleeding (hemorrhagic). Without oxygen, the brain tissue will begin to die. Depending upon severity and speed of intervention, a stroke can lead to minimal repercussions all they way up to coma or death.
I am an EE not an MD, so I can't give the exact cause for a coma (I'm not sure if the exact cause is known). Basically there is damage to the brain (drugs, strokes, traumatic brain injuries, hypoxia, medically induced, etc). There are different levels of a coma (some are more profound than others). The severity of the coma and the length of time in the coma affect the likelihood of a recovery. Unsurprisingly, a lower severity and a shorter time spent in a coma result in a better prognosis.
A stroke is when a blood clot (scab) blocks some blood flow in your brain; it starves the blocked area of blood and you get local damage/death of cells, but it's not big enough to take out your whole brain (usually). The rest of the brain keeps working.
Coma is when you're unconscious and won't wake up. That may or may not involve brain death. You can still have brain activity while in a coma.
Brain death is when "all" the electrical activity of the brain quits. The parts of the brain that matter to think are dead.
Any-Growth8158 t1_iujpel2 wrote
Brain dead is dead. No brain activity.
Coma is a deep state of unconsciousness. People will not react to painful stimuli, etc. They are not dead and there is minimal brain activity. They may or may not recover from being in a coma.
A stroke (in the brain) is a failure of the circulatory system to provide oxygen to the brain. It can be caused by either a blockage (ischemic) or bleeding (hemorrhagic). Without oxygen, the brain tissue will begin to die. Depending upon severity and speed of intervention, a stroke can lead to minimal repercussions all they way up to coma or death.