A coma is a deep state of unconsciousness. An individual in a 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 brain injury.
A coma rarely lasts more than 2 to 4 weeks. The outcome for coma depends on the cause, severity, and site of the damage. People may come out of a coma with physical, intellectual, and psychological problems. Some people may remain in a coma for years or even decades. For those people, the most common cause of death is infection, such as pneumonia.
NIH: National Institute of Neurological Disorders and Stroke
- Cerebral Hypoxia (National Institute of Neurological Disorders and Stroke) Also in Spanish
- Locked-In Syndrome (National Institute of Neurological Disorders and Stroke)
- Prediction of Recovery from Coma After CPR (American Academy of Neurology) - PDF
- Traumatic Brain Injury: Hope Through Research (National Institute of Neurological Disorders and Stroke) Also in Spanish
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
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- What Is a Coma? (Nemours Foundation)