vegetative state


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Related to vegetative state: Minimally conscious state

Vegetative State

 

Definition

A coma-like state characterized by open eyes and the appearance of wakefulness is defined as vegetative.

Description

The vegetative state is a chronic or long-term condition. This condition differs from a persistent vegetative state (PVS, a state of coma that lacks both awareness and wakefulness) since patients have awakened from coma, but still have not regained awareness. In the vegetative state patients can open their eyelids occasionally and demonstrate sleep-wake cycles. They also completely lack cognitive function. The vegetative state is also called coma vigil.

Causes and symptoms

The vegetative state can be caused by:
  • cardiac arrest
  • prolonged and profound hypoglycemia (an abnormal and severe decrease in blood sugar)
  • carbon monoxide poisoning
  • head injury
  • brain hemorrhage
  • compression of the brainstem
  • tumors
  • bilateral hemispheric demyelination (a loss of nerve cells)
  • injury of the brain following infections (meningitis or encephalitis)
  • neurodegenerative diseases
  • anencephaly (an abnormality of the brain and skull)
  • diffuse nerve cell injury
Patients in a vegetative state apparently have functioning of a special area in the brain called the reticular activating system (RAS) responsible for sleep-wake cycles. The connections that integrate more complex abilities such as awareness are interrupted. Patients in the vegetative state can open and close eyes spontaneously. They may appear to track or follow objects with their eyes. Patients may chew and swallow food placed in the mouth. The vegetative patient does not respond to sound, hunger, or pain. Patients cannot obey verbal commands and lack local motor responses. Additionally these patients cannot talk in comprehendible terms and they may become noisy, restless, and hypermobile. These patients are in a state of arousal but completely lack awareness.

Diagnosis

Diagnosis of vegetative state depends on the primary cause of brain dysfunction. A comprehensive history and neurological examination, neuroimaging studies, and chemical analysis of the blood are essential. Additionally, special tests such as cerebrospinal fluid (CSF, the fluid that bathes and nourishes the brain and spinal cord) analysis and electroencephalography, (EEG analyzes the electrical activity within the brain) may be indicated to establish a diagnosis.

Treatment

Treatment is directed to presenting symptoms and patient needs. Patients require constant monitoring and assistance with feeding, hydration hygiene, assisted movement (to help prevent ulcers and blood clots in the legs), and elimination of waste products.

Alternative treatment

There is no known alternative treatment for vegetative patients.

Prognosis

The prognosis is generally poor and the condition can persist chronically.

Prevention

There is no known prevention since this state can occur as a result of unavoidable situations such as an accident, tumor, and bleeding or genetic abnormality.

Key terms

Cognitive — The ability (or lack of) to think, learn, and memorize.
Hypermobility — Increased movement of joints.

Resources

Books

Goetz, Christopher G., et al, editors. Textbook of Clinical Neurology. 1st ed. W. B. Saunders Company, 1999.
Goldman, Lee, et al. Cecil Textbook of Medicine. 21st ed. W. B. Saunders Company, 2000.
Miller, Ronald D., et al, editors. Anesthesia. 5th ed. Churchill Livingstone, Inc., 2000.

vegetative state

a clinical condition in which there is complete absence of awareness of the self and the environment, accompanied by sleep-wake cycles, but with either partial or complete preservation of hypothalamic and brainstem autonomic functions; may be transient or permanent. There are multiple causes, all involving the brain, including traumatic and nontraumatic injuries, metabolic and degenerative disorders, and congenital malformations.

vegetative state

a physical condition in which a previously comatose patient continues to be unable to communicate or respond to stimuli, despite at times giving the appearance of wakefulness. The eyes may be open, but, because of senile brain disease, cerebral arteriosclerosis, or injury to the cerebral cortex, the patient remains immobile and must be fed and toileted, and all other physical needs must be attended to. It is important to speak to the patient, since it is not known whether the patient can hear.

vegetative state

Clinical medicine A state characterized by unresponsiveness to external stimuli Types Permanent VS, persistent VS

veg·e·ta·tive state

(vej'ĕ-tā-tiv stāt)
A clinical condition in which there is complete absence of awareness of the self and the environment, accompanied by sleep-wake cycles, but with either partial or complete preservation of hypothalamic and brainstem autonomic functions; may be transient or permanent. There are multiple causes, all involving the brain, including traumatic and nontraumatic injuries, metabolic and degenerative disorders, and congenital malformations.

vegetative state

See PERSISTENT VEGETATIVE STATE.

vegetative

1. concerned with growth and nutrition.
2. functioning involuntarily or unconsciously.
3. resting; denoting the portion of a cell cycle during which the cell is not replicating.
4. pertaining to plants.
5. asexual reproduction.

inherited vegetative dermatosis
see dermatosis vegetans.
vegetative nervous system
autonomic nervous system.
vegetative state
in neurological assessment, the animal is in a coma, but can be aroused. There is brainstem activity but cortical responses are absent.
References in periodicals archive ?
Between November 2005 and January 2009, Martin Monti and six other researchers in the United Kingdom and Belgium conducted fMRI brain scans of fifty-four vegetative state and minimally conscious state patients.
There is a small chance ([+ or -]5%) that patients in a vegetative state will respond favourably.
First verified in 2006 by a brain scan of a woman in a vegetative state, covert consciousness has been sought by researchers among other patients ever since.
The committee concluded that Aruna met most of the criteria of being in a permanently vegetative state.
Rory Rogers with his fiance Stacey Mckeowen before the assault which >left him in a persistent vegetative state Wales News Service
Hartstein's graph, the prognosis for someone who is in PVS 12 months into the accident is that there is a little chance of becoming conscious and a greater chance of dying or remaining in persistent vegetative state in the next seven months.
Prof Schwarzbauer said: "The accurate diagnosis of disorders of consciousness such as coma and persistent vegetative state is a major challenge for clinicians.
First they consider what the vegetative state is, what it's like to be in the vegetative state, what it's like to live with patients in the vegetative state and how society should deal with these patients, and a final section considers how decisions are to be reached.
Because I was in a position that I could have been left without the ability to speak, without the ability to see - capable of life but in a vegetative state without the ability to move, certainly on the right side, probably all sides, and clearly with the brain compromised.
Not only does the sick person in a vegetative state have the right to basic healthcare (warmth, cleanliness, hydration and nutrition) - such "natural" means of preserving life should be considered obligatory.
The woman - who can be referred to only as M - is not in a persistent vegetative state, but her family had called for her life-supporting treatment to be removed.
It set out to determine if amantadine given in a dose of 200-400 mg/day would improve functional recovery from posttraumatic vegetative state or minimally conscious state and if the gains in function persisted after the drug was discontinued.