Describe some difference between “persistent vegetative state” and “brain death”

Definitions:

Persistent vegetative state: A wakeful unconscious state that lasts longer than a few weeks.

Brain death: Irreversible brain damage causing the of independent respiration, regarded as indicative of death.

Differences:

Persistent vegetative state

• Has damage to areas of the brain responsible for consciousness, self-awareness, personality, head injury and oxygen deprivation.
• If coma lasts for more than a month or so, it is known as a persistent vegetative state.
• Brain loses higher functions, but can still maintain involuntary functions such as breathing and swallowing, heart rate and blood pressure. 
• The patient would require artificial feeding.
• Given adequate treatment the patient can survive for years and may recover towards the minimally conscious state or can gain complete recovery.

Brain death

• Not in coma. 
• The irreversible loss of brain function. 
• The patient is unconscious but still considered legally alive.
• They often still have a heartbeat, they breathe with the help of a ventilator.