hepatic coma

coma /co·ma/ (ko´mah) [L.] a state of profound unconsciousness from which the patient cannot be aroused, even by powerful stimuli.co´matose

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alcoholic coma  stupor accompanying severe alcoholic intoxication.

diabetic coma  the coma of severe diabetic acidosis.

hepatic coma  coma accompanying hepatic encephalopathy.

irreversible coma  brain death.

Kussmaul's coma  the coma and air hunger of diabetic acidosis.

metabolic coma  the coma accompanying metabolic encephalopathy.

uremic coma  lethargic state due to uremia.

coma vigil  locked-in syndrome.

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hepatic coma

n.

A coma occurring in advanced cirrhosis, hepatitis, poisoning, or other liver disease.

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hepatic coma,

a neuropsychiatric manifestation of extensive liver damage caused by chronic or acute liver disease. Either endogenous or exogenous waste toxic to the brain is not neutralized in the liver before being shunted back into the peripheral circulation of the blood, or substances required for cerebral function are not synthesized in the liver and therefore are not available to the brain. Commonly, ammonia, a by-product of protein metabolism that is toxic to the brain, is not converted to urea by the liver. The condition is characterized by variable consciousness, including lethargy, stupor, and coma; a tremor of the hands; personality change; memory loss; hyperreflexia; and hyperventilation. Respiratory alkalosis, mania convulsions, and death may occur. The outcome varies according to the pathogenesis of the condition and the treatment. Also called portal systemic encephalopathy. See also cirrhosis, hepatitis.

interventions Treatment in most cases includes cleansing enemas, low-protein diet, parenteral hydration with a balanced electrolyte solution, and specific treatment for the underlying cause. It may also include the use of neomycin orally to kill off bacteria and thus prevent elevated blood urea nitrogen levels.

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coma

a state of unconsciousness from which the patient cannot be aroused, even by powerful stimuli.

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alpha coma

coma in which there are electroencephalographic findings of dominant alpha-wave activity.

diabetic coma

the coma of severe diabetic acidosis. See also diabetes mellitus.

hepatic coma

results from reversible biochemical abnormalities of the cerebrum, caused by elevated blood levels of toxic substances such as ammonia, amino acids, short-chain fatty acids and beta hydroxylated biogenic amines that accumulate in severe liver disease. See also hepatic encephalopathy.

irreversible coma

coma in which for a period of 24 hours there is complete nonreceptivity and nonresponsivity even to the most intensely painful stimuli, no spontaneous movement or breathing, absence of elicitable reflexes, and a flat electroencephalogram. Called also brain death.

myxedema coma

the mental stupor caused by severe hypothyroidism; seen most often in Doberman pinchers, it is associated with hypoventilation, hypothermia, hypotension and bradycardia. Death may occur.