Question by all you need is LOVE, LOVE, LOVE: How long can you live in a coma WITHOUT TREATMENT?
okay, so i was writing this story ( something i do often :D) and this girl was in a coma. i am wondering how long its possible to remain in that state, just so i can make it seem more plausible.

real thorough answers please, and maybe a couple websites with information? Thanks!
What about the vegative state of a coma? How long can you live in that state without treatment, if at all?

Best answer:

Answer by Steve L
Coma is an extended period of unconsciousness from which a person cannot be aroused even with the most painful stimuli. Coma is not a disease. It is a symptom of a disease or a response to an event, such as a severe head injury, seizure or metabolic problem. Most comas do not last longer than four weeks. Some people in a coma shift to a persistent vegetative state, in which breathing, maintaining normal blood pressure, digesting and eliminating foods continues without the patient’s awareness. The vegetative state can last for years or decades. The outcome of a coma ranges from full recovery to death. Whether a person recovers, and to what extent, depends upon the cause of the coma and the type and extent of the brain damage.

A coma involves two different concepts: Reactivity and perceptivity.

The perceptivity concept refers to responses of the nervous system to learned stimuli. These types of stimuli may be learned through language or communication skills.
The reactivity concept refers to the inborn functions of the brain. These functions include the eyes, ears, responses to pain, wakefulness and turning ones head toward a sound of movement. These movements are also called reflexive movements.
A person in a coma does not experience reactivity or perceptivity. The patient can not be aroused by calling their name or experiencing pain.

Symptoms of a Coma

The main symptom of a coma is the inability to be aroused to consciousness. Other symptoms are: Lack of self-awareness, Lack of a sleep-wake cycle, Lack of purposeful movements, Lack of suffering and Impaired breathing.

What Causes a Coma?

A coma can be caused by a variety of things. The most often cause of coma is severe head injury. Other causes are: consumption of a very large amount of alcohol (toxic or metabolic coma), diabetes, morphine, shock or hemorrhage. Treatment varies depending on the cause. Overall, in coma cases, damage to the brain’s “thinking, and life support centers” have occurred. When damage has occurred, bleeding in the brain, swelling and congestion of the damaged tissue is present. In extreme cases, brain swelling is so great that portions of the brain must be forcible squeezed out of the skull. This dead or “dying” tissue is then surgically removed. An alternative to squeezing portions of the brain out of the skull is to saw off the skull and place it in a cold storage to better accommodate the swollen brain.

What happens during a coma?

There are different stages of a coma. Most people believe that a person in a coma is in a deep sleep. This is not entirely true. Some stages of coma resemble a deep sleep but not all. The progress of coma is measured by the patient’s increasing awareness of external stimuli. There are many levels of coma which the patient will pass through as functionality increases. Depending on the stage, a person in a coma may make movements, sounds and experience agitation. Coma patients may also have reflex activities that mimic conscious activities. Sometimes, coma patients must be restrained to prohibit them from removing tubes and IVs.

Emerging from a Coma

When a person begins to emerge from a coma, they begin to react to certain stimuli. However, to regain consciousness, both reactivity and perceptivity must be present. Reactivity and perceptivity are necessary for a state of awareness. It is often the case that some parts of perceptivity such as speech and self care must be relearned.

A beneficial Coma

Sometimes a coma may be chemically induced by a doctor to aid in medical treatment and recovery. This usually happens during a head injury.

Coma Statistics

Every ten minutes head injury claims the life of another child.
Head trauma is the number one cause of death and disability among people between the ages of 1 and 44.
About 5% to 10% of all coma patients are incapable of conscious behavior, and end up vegetative, which most of the public think of as prolonged coma.

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