-Starts with portal hypertension
-Portal hypertension is pressure of > 12mmHg in the portal veins
-There can be multiple causes of portal hypertension ranging from pre, intra, and post hepatic origins
-The most common cause of intra-hepatic hypertension is cirrhosis
-The main contributor to this pathophysiology is Nitric Oxide
-Nitric Oxide is known to cause vasodilation
-Strange: Nitric Oxide levels vary in patients with liver cirrhosis
-Nitric Oxide is low at the level of the liver, therefore, the portal veins become constricted
-Now... along with obstruction from cirrhosis, these vessels are vasoconstricted, so they cause an increase in pressure resulting in portal hypertension
still taking about veins here
-At the level of the splanchnic arteries, Nitric Oxide is high
-It is unknown why this happens, but because Nitric Oxide is high, it causes vasodilation
-Vasodilation causes the pressure to drop
-Hence, it is known to cure hypertension
*Patient's with liver cirrhosis who are hypotensive have a very poor prognosis. Patients with a MAP of < 82 mmHg with cirrhosis have a 2 year survival rate of only 20%.
*You need to be very careful with managing their blood pressure, especially if they have ascites. Reconsider stopping their anti-hypertensive meds.