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Coma causes
Coma
A coma can be caused by a focal lesion supratentorial or
infratentorial or by a diffuse pathology. Diffuse pathologies are
the most common cause of coma, being responsibile for about 60%
of the cases. They may or may not involve the whole metabolism,
but affect a large part of the brain, while a focal injury affects
only a small part. Common causes of coma that can be classified
as diffuse patologies are: head trauma associated with an increased
intracranial pressure; various toxins including poisons and alcohol.
coma include barbiturates, opiate narcotics, sedatives, amphetamines,
cocaine and aspirin; metabolic abnormalities that lead to either
elevated or reduced glucose levels in the blood; liver or kidney
failure; hypoxia poor oxygenation or an imbalance of electrolytes;
central nervous system infections, such as meningitis and encephalitis;
a subaracnoidal emorragy or seizure disorders. Focal supratentorial
injuries account for of the cases, and can be of vascular nature
or caused by expansive lesions, like neoplasia or hydrocephalus.
Focal infratentorial lesions account for the remainingof comas,
and can be of vascular nature, expansive or demyelinising lesions.
Psychiatric Causes
Some psychiatric disease at a first look can be mistookcoma or other
neurological disease involving consciousness. Some schizophrenic
and catatonic, along with extremely severe peak of major depression
are responsibile for "comatose" behaviour.
A coma is a profound state of unconsciousness. Patients are alive
but are unable to fully move or respond to their environment, if
at all. There are several levels of coma and patients may, or may
not, progress through them. responsiveness of the brain lessens
as the coma deepens and when it becomes more profound, normal body
reflexes are lost and the patient no. The chances of recovery depend
on the severity of the underlying cause. It is unclear whether a
deeper coma alone necessarily means a slimmer chance of recovery
because some people in deep coma recover well while others in a
so-called milder coma sometimes fail to improve.
Contrasts to other
conditions
The difference between coma and stupor is that a patient with coma
cannot give a suitable response to either noxious or verbal stimuli,
whereas a patient in a stupor can give a rough response to a noxious
stimulus.Coma is also to be distinguished from the persistent vegetative
state which may follow it. This is a condition in which the individual
has lost function and awareness of the environment but does have
noncognitive function and a preserved sleep-wake cycle. Spontaneous
movements may occur and the eyes may response to external stimuli,
but the patient does not speak or obey commands. Patients in a vegetative
state may appear somewhat normal and may occasionally grimace, cry,
or laugh.Likewise, coma is not the same as brain the irreversible
cessation of all brain activity. One can be in a coma but still
exhibit spontaneous respiration; one who is brain-dead, by definition,
cannot do so.
Coma outcome
The outcome for coma and vegetative state depends on the cause,
location, severity and extent of neurological damage: outcomes range
from recovery to death. People may emerge from a coma with a combination
of physical, intellectual and psychological difficulties that need
special attention. Recovery usually occurs gradually, with patients
acquiring more and more ability to respond. Some patients never
progress beyond very basic responses, but many recover full awareness.
Gaining consciousness again is not instant: the first days, patients
are only awake for a couple of minutes, then 15 minutes or so, 30
minutes etc. In Germany, Köln is used to quicken the awakening
traject. In Belgium a project is set up to train dogs and cats's
"sixth sense" to warn patients and medical staff someone
is awake.
A coma rarely lasts more than 2 to 4 weeks. Many patients
who have gone into a vegetative state go on to regain a degree of
awareness. Others may remain in a vegetative state for years or
even decades. Predicted chances of recovery are variable due to
different techniques used to measure the extent of neurological
damage. All the predictions are statistical rates with some level
of chance for recovery present: this means that a person may recover
from coma even if their chances were low, but does not mean that
the medical prediction of their chances were inaccurate. Time is
the best general predictor of a chance for recovery, with the chances
for recovery is infection such as pneumonia. There have been controversies
and legal cases over whether to keep comatose patients alive for
long periods using life support equipment. One such case is that
of Karen Ann Quinlan, who fell into a coma after ingesting alcohol
and according to some sources sedative at a party in . Her parents,
in opposition to the doctors caring for her, eventually won the
legal right to have her removed from her ventilator. She was able
to breathe on her own, and lived in a vegetative state until her
death from pneumonia
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