A coma is when a person is in such a deep state of unconsciousness that the individual is unable to be awakened. Severe illness and injuries such as concussions and brain trauma are the most frequent causes of comas. It derives from the Greek word koma, meaning 'deep sleep."
A coma is also called a persistent vegetative state. That means that a person who is comatose is not able to respond to the environment; in fact, he or she is not even aware of the surroundings, even though the person could appear normal. Although their eyes may open in response to stimuli and parts of the body could make spontaneous movements, the person does not talk or react to commands.
Although the higher brain functions are gone when a person remains in a coma, the autonomic systems remain largely intact, so breathing and blood circulation continue. However, a coma is not synonymous with brain death. People are in comas an average of two to four weeks. If they awaken from a temporary coma caused by head injury, which many do awaken from slowly over time, persons who have been in a coma may experience amnesia, brain damage or other effects from the brain injury.
Consulting with an Arizona lawyer can be helpful in accidents that involve comas. A lawyer might be able to ascertain negligence and seek accident compensation, especially in cases of permanent disability and when there is a need for long-term care. A lawyer may also be able to seek compensation for medical expenses, rehabilitation and therapy.
Source: NINDS, "What is Coma?," Accessed on Jan. 26, 2015