Portal systemic encephalopathy.

Portal systemic encephalopathy is a neuropsychiatric disorder that occurs secondary to chronic liver disease. It is a chronic and disabling disorder that must be treated concurrently with liver disease. In chronic liver disease, the regenerative capacity of the liver to produce new cells is eventually hampered and scar tissue develops. Scarring reduces blood flow through the liver. The vein most affected is the portal vein which contributes 75 percent of the blood to the liver as it evolves from tributaries off the abdominal organs. To eliminate the high pressure in the portal vein caused by the reduced blood flow, the portal vein develops collateral vessels that bypass the liver and drain directly into the inferior vena cava. When blood is not cleared, or when hepatic functioning fails, toxins accumulate in the circulation and affect the central nervous system. The neuropsychiatric manifestations that occur represent the symptoms seen in portal systemic encephalopathy. With renewed understanding of the disease and its neuropsychiatric manifestations, both clinicians and patients are able to minimize its untoward effects. This article reviews the pathogenesis, stages, diagnosis and treatment of the disease and aims at giving nurse practitioners a thorough review so they can better teach patients how to help themselves.