Liver and Biliary Disease Flashcards
Percentage of cardiac output received by the liver
25%
Portal vein
Confluence of the splenic vein and superior mesenteric artery. Provides 75% of blood flow to liver and accounts for 50% of oxygen delivery
Hepatic artery
provides 25% of blood flow and 50% of oxygen
Control of blood flow to liver
Hepatic artery inverse relationship with portal venous flow. Portal flow decrease then hepatic dilates to maintain adequate oxygenation. One-way mechanism. Portal venous flow indirectly modulated by arterial tone of splanchnic vessels and intrahepatic resistance. Portal vein pressure too high the systemic circulation dilates
function of the liver
Metabolic processes
Filter and transform substances in the blood
Synthesizes most coagulation factors and proteins. Increases bleeding and thrombotic risk in patients
Filter and transform substances in the blood
Nutrients and other substances from the digestive tract enter the liver via portal vein (first pass)
If portal hypertension exists, portosystemic shunts arise that allow blood flow to bypass the liver. Bypasses metabolic and detoxification process leading to hepatic encephalopathy, sepsis, and alterations in drug biotransformation
Most common viral hepatitis causing the need for liver transplantation in the US
Hep C
Wilsons disease
Autosomal recessive disease characterized by impaired copper metabolism
a-antitrypsin deficiency
Genetic disorder that results in defective production of a-antitrypsin protein. This protein protects the liver from neutrophil elastase. Disorder also can lead to panlobular emphysema and COPD. Liver transplant is the only cure for liver disease related to this protein. New liver produces the protein
Hemochromatosis
disorder of excess iron in the body that leads to multi organ dysfunction. Causes by excessive absorption by the GI tract, repeat blood transfusion, or high doses of iron
