Thirty years of the vegetative state: clinical, ethical and legal problems.

The vegetative state is the rarest form of disability in patients now frequently rescued from life-threatening severe brain damage by resuscitation and intensive care. Many doctors have never seen such cases, yet it provokes great interest among professionals and the public because of the paradox of a person who is awake yet not aware. The commonest cause is head injury and it is more common in countries with a high incidence of severe head injury. The most consistent brain damage is in the subcortical white matter of the cerebral hemispheres and in the thalami; although the cerebral cortex is often severely damaged, it may be relatively spared. Diagnosis depends on prolonged expert observation to determine that there is no evidence of awareness in spite of a wide range of reflex responses, some of which may involve cortical activity. Functional imaging confirms that there is some residual cortical function in many vegetative patients. Mistaken diagnosis is less likely since the recent definition of clinical criteria for the vegetative state and for the minimally conscious state. Many patients recover consciousness and even regain independence after a month in a vegetative state after head injury, but few do so after non-traumatic insult. The longer the state persists the less likely the recovery, and eventually permanence can be declared. Patients can survive for many years in a vegetative state. Many consider that indefinite survival in a vegetative state is of no benefit to the patient and that there is no moral or legal obligation to continue life-sustaining treatment, including artificial nutrition and hydration. Ethical issues include how to respect the autonomy of the legally incompetent patient, and uphold the right to refuse unwanted treatment. Many cases have been brought to court in several North American, Northern European and some other jurisdictions where it has been ruled that it is legally permissible to withdraw life-sustaining treatment once a patient is declared permanently vegetative, and such withdrawal seems likely to be what that person would want done.