Synonym(s): Persistent Vegetative State

What is Coma?

A coma, sometimes also called persistent vegetative state, is a profound or deep state of unconsciousness. Persistent vegetative state is not brain-death. An individual in a state of coma is alive but unable to move or respond to his or her environment. Coma may occur as a complication of an underlying illness, or as a result of injuries, such as head trauma. . Individuals in such a state have lost their thinking abilities and awareness of their surroundings, but retain non-cognitive function and normal sleep patterns. Even though those in a persistent vegetative state lose their higher brain functions, other key functions such as breathing and circulation remain relatively intact. Spontaneous movements may occur, and the eyes may open in response to external stimuli. Individuals may even occasionally grimace, cry, or laugh. Although individuals in a persistent vegetative state may appear somewhat normal, they do not speak and they are unable to respond to commands.

Is there any treatment?

Once an individual is out of immediate danger, the medical care team focuses on preventing infections and maintaining a healthy physical state. This will often include preventing pneumonia and bedsores and providing balanced nutrition. Physical therapy may also be used to prevent contractures (permanent muscular contractions) and deformities of the bones, joints, and muscles that would limit recovery for those who emerge from coma.

What is the prognosis?

The outcome for coma and persistent vegetative state depends on the cause, severity, and site of neurological damage. Individuals may emerge from coma with a combination of physical, intellectual, and psychological difficulties that need special attention. Recovery usually occurs gradually, with some acquiring more and more ability to respond. Some individuals never progress beyond very basic responses, but many recover full awareness. Individuals recovering from coma require close medical supervision. A coma rarely lasts more than 2 to 4 weeks. Some patients may regain a degree of awareness after persistent vegetative state. Others may remain in that state for years or even decades. The most common cause of death for someone in a persistent vegetative state is infection, such as pneumonia.

What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS) and other institutes of the National Institutes of Health (NIH) conduct research related to coma in their laboratories at the NIH and also support additional research through grants to major medical institutions across the country. Much of this research focuses on finding better ways to prevent and treat coma.


Coma / Traumatic Brain Injury Recovery Association, Inc

8300 Republic Airport, Suite 106
Farmingdale, NY 11735
Phone: 631.756.1826
Fax: 631.756.1827

Brain Trauma Foundation

7 World Trade Center
250 Greenwich Street, 34th Floor
New York, NY   10017
Phone: 212.772.0608
Fax: 212.772.0357

Brain Injury Association of America, Inc.

1608 Spring Hill Rd., Suite 110
Vienna, VA 22182
Phone: 703.761.0750
Toll-free: 800.444.6443
Fax: 703.761.0755

Family Caregiver Alliance/ National Center on Caregiving

785 Market St., Suite 750
San Francisco, CA   94103
Phone: 415.434.3388
Toll-free: 800.445.8106
Fax: 415.434.3508

National Rehabilitation Information Center (NARIC)

8201 Corporate Drive, Suite 600
Landover, MD   20785
Phone: 301.459.5900
Toll-free: 800.346.2742
TTY: 301.459.5984 
Fax: 301.562.2401

National Stroke Association

9707 East Easter Lane, Suite B
Centennial, CO 80112-3747
Phone: 303.649.9299
Toll-free: 800.STROKES (787.6537)
Fax: 303.649.1328

Source: National Institutes of Health; National Institute of Neurological Disorders and Stroke

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 9/18/2012...#6007