lecture 19 - portal hypertension Flashcards
What is the primary haemodynamic consequence of portal hypertension?
Development of Portal-System shunts, where portal blood is shunted into the venous system, bypassing the liver
What is the effect of portal systemic shunts on portal venous blood flow?
Decreased portal venous blood flow
What are the 5 key signs/symptoms of portal hypertension (‘CAVES’)?
C - caput medusae
A - Ascites
V - varices
E - Encephalopathy
S - splenomegaly
Where do varices form with portal hypertension?
Oesophagus, stomach, anus
What causes the formation of varices with portal hypertension?
Increased pressure into shunt vessels causes them to outpouch, potentially making them vulnerable to rupture
What is Caput Medusae?
Spider-like engorged superficial veins that radiate from the umbilicus across the abdomen, generally caused by portal hypertension
Why is bleeding from varices more likely to be profuse in cases of portal hypertension?
Damaged liver is producing less vitamin K and clotting factors, meaning the blood is less prone to clot
What are the non-pharmacological treatments for varices caused by portal hypertension?
Shunt surgery, banding of varices
What is hepatic encephalopathy?
Cerebral dysfunction caused by reduced hepatic detoxification and ammonia processing due to shunting of portal blood from the liver.
What toxin primarily causes brain damage in hepatic encephalopathy?
Ammonia - abnormally high levels in the blood because not being converted to urea in the blood
What are some of the precipitating factors for hepatic encephalopathy?
Things that increase ammonia levels in the blood (internal bleeding, high protein diet, etc.) and things that worsen liver function (alcohol, infection, shunts, etc.)
Why dos ascites often occur with portal hypertension?
There is increased hydrostatic pressure in shunt vessels, leading to leaking out of fluid into the peritoneal space
