Portal hypertension Flashcards
the liver is very richly perfused for nourishment & functional reasons what is the inflow and outflow of blood to the liver (hepatic portal system)
- 70% of blood arrives via portal vein (from digestive tract)
- 30% via hepatic artery (oxygenated blood for liver function)
- outflow: hepatic veins 100%
what is portal hypertension
an increase in pressure in the hepatic portal system, greater than 12 mmHg: normal is 5-10
what is normal pressure in the hepatic portal system
normal is 5-10
what pressure causes portal hypertension
greater than 12 mmHg
what is the etiology of portal hypertension?
- demands on pre,post or intrahepatic location
- mostly d/t cirrhosis (intrahepatic)
what is an post hepatic obstruction causing portal hypertension
refers to any obstruction to blood flow through hepatic veins beyond liver
what is a prehepatic obstruction causing portal hypertension
tumor causing obstruction in the portal system
what is a intrahepatic obstruction causing portal hypertension
such as cirrhosis causing obstruction in liver from fiber build up
Major complications from portal hypertension
-ruptured varix (dilation of associated vien) eg. esophageal vein, hemmoroidal vein
what is a varix
dilation of associated vein
what is the difference between a varix and an aneurysm?
anuerysm=localized bulge
varix=distention/dilation of whole vein
what are the other complications of portal hypertension?
- ascites
- portosystemic shunts (hepatic portal-the rest of venous system build up of pressure in portal system, channels of veins to other parts of venous system to relive pressure, blood bypases liver than cannot detoxify the blood and can affect body)
- spleenomegaly (vessels become engorged (splenic vein) increase in hydrostatic pressure, fluid is pushed into spleen, enlarging the spleen
