Module 7: Liver anatomy and Physiology (YT video) TRAT

Question 1

Common causes of Cirrhosis

Answer 1

-increased EtOH consume
-hepatic viral infections
-cystic fibrosis

Question 2

Which blood vessels combine to build the Sinusoid?

Answer 2

Hepatic artery and the portal vein

Question 3

What is the portal triad?

Answer 3

-bile duct + portal vein + hepatic artery

Question 4

Function of stellar cells

Answer 4

-in the perisinusoidal space
-in healthy tissue: store Vitamin A (quiescent, dormant)

-in damaged tissue: damaged tissue activates stellate cells -> secrete TGF-ß -> producing collagen leading to fibrosis and scar tissue

-> this is the normal wound-healing process, but when stellate cells are constantly activated they cause fibrosis

Question 5

What happens to central veins and sinusoids when scar tissue builds up?

Answer 5

-it compresses the central veins and sinusoids

-Ascites:
intrasinusoidal or portal hypertension -> fluids in the blood vessel are pushed to open spaces like the peritoneal cavity

-Splenomegaly:
caused by Ascites (fluid in the cavity)

-Portosystemic shunt:
the pressure shifts blood from the circulation away from the liver

-Hepatorenal failure: due to portosystemic shunt
renal vasoconstriction triggered by altered blood flow (not fully understood) -> lower filtration

-decrease in liver function:
less blood flow to the liver caused by the pressure build-up

-toxin build-up -> worst case: coma
Asterixis (tremor hand) caused by Ammonia build-up

-estrogen build-up:
gynecomastia, spider angiomata, palmar erythema

-Jaundice: bilirubin builds up
bilirubin conjugation and excretion is decreased

-Hypoalbuminemia
liver produces albumin

-coagulopathy
the liver produces clotting factors

Question 6

What is a portosystemic shunt?

Answer 6

the pressure shifts blood from the circulation away from the liver

Question 7

What are the common complications of portosystemic shunting?

Answer 7

-renal vasoconstriction triggered by altered blood flow (not fully understood)

-low kidney blood flow
-lower filtration
-> leading to Hepatorenal failure

Question 8

What is the result of an increase in unconjugated bilirubin?

Answer 8

Jaundice

Question 9

What are the differences between compensated versus decompensated cirrhosis?

Answer 9

-compensated: early with a small amount of fibrosis, the liver still does its job -> asymptomatic or non-specific symptoms (weight loss, fatigue, weakness)

-decompensated: liver can’t function
Jaundice, Pruritus (ichty skin)
Ascites
Hepatic encephalopathy (confusion)
easy bruising (low coagulation factors)

Question 10

What are Labs that are indicative of cirrhosis?

Answer 10

-gold standard: liver biopsy

-elevated bilirubin
-elevated LFT: AST, ALT, ALP, Gamma Glutamyl Transpeptidase (GGT)

-Thrombocytopenia: low platelet count