07: Liver Liver Liver

Question 1

hepatocellular dmg

1. will see what in SA
2. in LA?

Answer 1

1. ^AST, ALT
2. ^AST, SDH +/- GGT

Question 2

(cholestasis)

1. what is it?
2. how is most bilirubin produced?

Answer 2

1. obstruction of bile flow (bilirubin) in liver
2. degradation of RBC by hemoglobin

Question 3

(pre-hepatic cholestasis)

1. what causes?
2. How are ALP and GGT affected?
3. may see increases in what if hepatcellular hypoxia?

Answer 3

1. ^RBC destruction (liver can’t take up all of it)
2. WRI
3. ALT, AST, SDH

Question 4

(intrahepatic cholestasis)

1. two reasons liver can’t clear?

Answer 4

1. liver failure and funcional intrahepatic cholestasis (interference of receptor uptake of bilirubin)

Question 5

Liver failure

1. decreases in what?
2. increases in what?
3. Will only see abnormalities if liver reaches what % of function?

Answer 5

1. albumin, cholesterol, glucose, urea, USG
2. bilirubinemia/uria, PT, PTT, FDPs
3. 30%

Question 6

(Post-hepatic Cholestasis)

1. hyperbilirubinemia from what?
2. increases in what (not seen with other cholestasis)?
3. will see increase in what with time/severity?

Answer 6

1. blocked bile flow (in liver or distal (gall bladder))
2. ALP and GGT
3. cholesterol

Question 7

1-2. Which two measures are most helpful in determining liver function?

Answer 7

1. serum bile acids
2. blood ammonia

(albumin, BUN, cholesterol, glucose, USG, PT/PTT affected by too much)

Question 8

(Bilirubin)

1. low levels normally excreted in what animal?
2. will see increases with what three things?

Answer 8

1. dog (NOT cat)
2. hemolysis (poss high)

cholestasis (high or mild)

dec liver fx (mild)

Question 9

(bile acids)

1. produced in liver from what?
2. reabsorbed where?
3. serum bile acid conc^ with what?

Answer 9

1. cholesterol
2. portal circulation (then extracted by hepatocytes)
3. decreased liver fx and post & hepatic cholestasis

Question 10

1-5. What five reasons do you an increase in serum bile acids?

6. when would you see decrease?

Answer 10

1. post-prandial
2. decreased liver function (not enuff recovery)
3. cholestasis (reflux into circulation)
4. shunt (from intestines into circulation)
5. spontaneous gall bladder contraction
6. intenstine malabsorption

(insufficient liver production NOT NOTED)

Question 11

(Blood Ammonia)

1. produced where?
2. Liver has large reserve capacity for detoxifying ammonia… so what does this mean (relative to bile acids)?

Answer 11

1. in intestines by microbial digestion of AA and urea

(then portal to liver, converted to urea)

2. LESS SENSITIVE than measure of bile acids (for liver fx)

Question 12

1-3. What three things cause hyperammonia

Answer 12

1. decreased liver function (most common)
2. ammonia overload from diet (ruminants)
3. excessive gut flora production/compromised gut wall (colic in E)

(hypoammonemia not significant)

Question 13