Hepatic Encephalopathy was found in 5-Minute Clinical Consult which helps you diagnose, treat, and follow up on over 900 medical conditions seen in everyday practice.
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- Reversible altered mental and neuromotor functioning associated with acute or chronic liver disease and/or portal systemic shunting of blood
- The prominent features are confusion, impaired arousability, and a “flapping tremor” (asterixis).
- System(s) affected: Gastrointestinal; Nervous
- Synonym(s): Portosystemic encephalopathy; Hepatic coma; Liver coma
Predominant sex: Male = Female (reflecting underlying liver disease)Prevalence
- Occurs in 1/3 of cirrhosis cases
- Occurs in all cases of fulminant hepatic failure
- Present in nearly 1/2 of patients who require transplantation
- Parallels the age predominance of fulminant liver disease: Peaks in the 40s; cirrhosis peaks in the late 50s; may occur at any age
Risk FactorsIn patients with underlying liver disease, precipitating factors include:
- Infection (overt or occult, including spontaneous bacterial peritonitis)
- GI hemorrhage
- Use of sedative or opiate drugs
- Fluid or electrolyte disturbance (Na+, K+, Mg2+, or other electrolyte depletion)
- Transjugular intrahepatic portosystemic shunt (TIPS)
- Conditions such as cystic fibrosis, α-1-antitrypsin deficiency, and Wilson disease can contribute to hepatic encephalopathy (HE).
- Recognize early signs and seek prompt treatment.
- Avoid nonessential medications, particularly opiates and sedatives.
- Failure of liver to detoxify agents noxious to the CNS (e.g., ammonia, mercaptans, fatty acids)
- Increased aromatic and reduced branched-chain amino acids in blood
- These act as false neurotransmitters, possibly inter-acting with the γ-aminobutyric acid (GABA) receptor
- Shunting of intestinal blood through the severely diseased liver without the intervention of viable liver cells
- Most common in long-standing cirrhosis of the liver with spontaneous shunting of intestinal blood through collateral vessels
- Shunting of such blood through collateral circulation or surgically constructed portacaval shunts
- TIPS, a widely used radiologically inserted shunt to lower portal pressure, produces HE.
- Acute onset of HE: Search for risk factors.
Commonly Associated Conditions
- Occurs rarely with portacaval shunt with normal liver function
- May occur as a complication of acute fatty liver of pregnancy