Induced coma - Wikipedia, the free encyclopedia


** Induced coma **

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A *barbiturate-induced coma*, or *barb coma*, is a temporary coma (a deep
state of unconsciousness) brought on by a controlled dose of a barbiturate
drug, usually pentobarbital or thiopental. Barbiturate comas are used to
protect the brain during major neurosurgery, and as a last line of
treatment in certain cases of status epilepticus that have not responded to
other treatments. Because patients are often seriously ill or injured, and
are under general anesthesia and in a coma, careful airway management,
which involves some form of mechanical ventilation, is needed.

Barbiturates reduce the metabolic rate of brain tissue, as well as the
cerebral blood flow. With these reductions, the blood vessels in the brain
narrow, decreasing the amount of space occupied by the brain, and hence the
intracranial pressure. The hope is that, with the swelling relieved, the
pressure decreases and some or all brain damage may be averted. Several
studies have supported this theory by showing reduced mortality when
treating refractory intracranial hypertension with a barbiturate

Controversy exists, however, over the benefits of using barbiturates to
control intracranial hypertension. Some studies have shown that
barbiturate-induced coma can reduce intracranial hypertension but does not
necessarily prevent brain damage. Furthermore, the reduction in
intracranial hypertension may not be sustained. Some randomized trials have
failed to demonstrate any survival or morbidity benefit of induced coma in
diverse conditions such as neurosurgical operations, head
trauma,^[4]intracranial aneurysm rupture, intracranial hemorrhage, ischemic
stroke, and status epilepticus. If the patient survives, cognitive
impairment may also follow recovery from the coma.^[5]

About 55% of the glucose and oxygen utilisation by the brain is meant for
its electrical activity and the rest for all


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