A vegetative state is a rare condition, caused by brain damage, in which a person comes out of a coma and is fully awake but they have no sense of awareness.
Someone who is in a vegetative state is:
- not aware of their surroundings
- not aware of bodily sensations, such as feeling pleasure or pain
- not able to follow and understand speech
- not able to have thoughts, memories, emotions, and intentions of any kind
So while technically they may be awake, what they are experiencing is no different from when they were in a coma.
However, as some sections of their brain are still functioning, they may perform a number of reflex actions that they are unaware of, such as:
- sleeping and waking at regular intervals
- making movements with their mouth such as smiling and grimacing
- gripping objects or other people’s hands
Read more about the symptoms of a vegetative state.
Causes
A vegetative state is caused by injury to the parts of the brain which control functions such as thinking, awareness and emotion. The damage can be:
- a traumatic brain injury – caused by a severe head injury such as that sustained during a car accident or a fall from a great distance
- non-traumatic brain injury – where the injury to the brain is caused by a health condition such as a stroke or Alzheimer's disease
Read more about the causes of a vegetative state.
Types of vegetative state
Vegetative states are grouped into two types depending on the length of time that a person has been in one. These are:
- persistent vegetative state – where a person has been in a vegetative state for more than four weeks
- permanent vegetative state – where a person has been in a vegetative state for more than six months as a result of non-traumatic brain damage, or 12 months as the result of traumatic brain damage
Confirming vegetative state
Health professionals have to be very precise in diagnosing vegetative state as there is always the possibility that a person could have awareness but is unable to express it.
For example, there is a condition called "locked-in syndrome" where a person is fully aware but is unable to move any of their muscles, so they are unable to move or speak.
There is a rigorous checklist that has to be followed when diagnosing a vegetative state, such as checking whether the symptoms may actually be due to a treatable condition such as a brain tumour.
Read more about diagnosing a vegetative state.
Chances of recovery
The chances of a person recovering from a vegetative state depend on:
- the type of brain damage they had
- their age
- the amount of time they have spent in a vegetative state
In a young person under the age of 20 who experiences traumatic brain damage, the chances of making a recovery are around 1 in 5.
An older person over the age of 40, who is an persistent vegetative state due to a non-traumatic brain damage, has an extremely small chance of making a recovery.
People who do make a recovery are often likely to have life-long physical and mental disabilities resulting from the damage to their brain.
Read more about recovering from a vegetative state.
Withdrawing treatment
If health professionals and family members agree that there is no point in continuing treatment then a court order can be sought to withdraw treatment.
This would usually be recommended if a person was in a vegetative state for 12 months and showed no sign of recovery.
In such a circumstance nutritional support is withdrawn and then the person is sedated so they can die peacefully in their sleep.
