Hepatic Encephalopathy


Multimedia

Definition

Hepatic encephalopathy is a worsening of brain function that occurs when the liver is no longer able to remove toxic substances in the blood.


Alternative Names

Hepatic coma; Encephalopathy - hepatic


Causes, incidence, and risk factors

Hepatic encephalopathy is caused by disorders that affect the liver. These include disorders that reduce liver function (such as cirrhosis or hepatitis) and conditions in which blood circulation does not enter the liver. The exact cause of hepatic encephalopathy is unknown.

An important job of the liver is to change toxic substances that are either made by the body or taken into the body (such as medicines) and make them harmless. However, when the liver is damaged, these "poisons" may build up in the bloodstream.

Ammonia, which is produced by the body when proteins are digested, is one of the harmful substances that is normally made harmless by the liver. Many other substances may also build up in the body if the liver is not working well. They can cause damage to the nervous system.

Hepatic encephalopathy may occur suddenly in people who previously had no liver problems when damage occurs to the liver. More often, the condition is seen in people with chronic liver disease.

Hepatic encephalopathy may be triggered by:

  • Dehydration
  • Eating too much protein
  • Electrolyte abnormalities (especially a decrease in potassium) from vomiting, or from treatments such as paracentesis or taking diuretics ("water pills")
  • Bleeding from the intestines, stomach, or esophagus
  • Infections
  • Kidney problems
  • Low oxygen levels in the body
  • Shunt placement or complications (See: Transjugular intrahepatic portosystemic shunt )
  • Surgery
  • Use of medications that suppress the central nervous system (such as barbiturates or benzodiazepine tranquilizers)

Disorders that can mimic or mask symptoms of hepatic encephalopathy include:

Hepatic encephalopathy may occur as an acute, potentially reversible disorder. Or it may occur as a chronic, progressive disorder that is associated with chronic liver disease.


References

Garcia-Tsao G. Cirrhosis and its sequelae. In: Goldman L, Ausiello D, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 156.


Request An Appointment

Review Date: 10/16/2011
Reviewed By: George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2004 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.

adam.com
Last Updated 11/15/2011
Find a Doctor

e.g., "allergy," "diabetes"

US News Best Hospital AwardANCC Magnet Association AwardBest Doctors 2011-2012 AwardConsumer Choice #1 Award 2011-2102US News Best Medical Schools 2011 Award

Disclaimer: The information on this website is for general informational purposes only and SHOULD NOT be relied upon as a substitute for sound professional medical advice, evaluation or care from your physician or other qualified health care provider.