12. Liver function

Question 1

Functions of the liver (7)

Answer 1

1) acid/base balance
2) fluid and electrolyte homeostasis
3) detoxification
4) antimicrobial
5) clotting factors
6) protein synthesis
7) glycogen storage

Question 2

Single most abundant serum protein

Answer 2

Albumin

Question 3

What clotting factors does the liver synthesise?

Answer 3

2, 7, 9, 10

Question 4

what antithrombotic factors does the liver synthesise?

Answer 4

Antithrombin III

protein C

protein S

Question 5

Where is Carbamoylphosphate synthetase found?

Answer 5

all but last 1- 2 hepatocytes round terminal hepatic venule

ammonia metabolism

Question 6

‘Fed’ state

Answer 6

liver synthesises glycogen from glucose

perivenular hepatocytes

Question 7

‘Fasted’ state

Answer 7

liver synthesises glucose

periportal hepatocytes

Question 8

Bile composition

Answer 8

Phospholipids

Cholesterol

Water

Inorganic electrolytes

Bile acids

Bile pigments

Question 9

How much bile is excreted per day?

Answer 9

500ml – 600ml

Question 10

What are primary bile acids synthesised from?

Answer 10

cholesterol in the liver

Question 11

\What are secondary bile acids synthesised from?

Answer 11

degradation of primary bile acids by bacteria in the gut

Question 12

What does bile acid conjugation do?

Answer 12

↓ passive diffusion

accumulation in gut lumen

facilitates fat digestion and absorption

Question 13

Enterohepatic circulation of bile salts

Answer 13

Hepatocyte

Biliary tree

Small bowel

Enterocytes

Portal blood

Hepatocyte

Question 14

How much of the bile salts are conserved in enterohepatic circulation?

Answer 14

90%

Question 15

How many times does the bile acid pool circulates daily

Answer 15

5-15 times

Question 16

Bilirubin metabolism

Answer 16

haem →biliverdin by Haemoxygenase

biliverdin → unconjugated bilirubin by Biliverdin reductase

Question 17

What percentage of bilirubin is derived from haem released by breakdown of erythrocytes?

Answer 17

80%

Question 18

Paracetamol overdose: clinical features

Answer 18

Fresh bruises

Liver flap

Abdominal pain

Mildly jaundiced

Patient is drowsy but obeying commands

Pear drops

Question 19

Prothrombin time

Answer 19

A measure of clotting of the blood

Question 20

Urea and electrolytes (U+Es)

Answer 20

Na, K, U, Creat

renal function and electrolyte balance

Question 21

Liver function tests (LFTs)

Answer 21

AP, ALT, Bil, Alb

Reflect liver damage

Question 22

pH

Answer 22

Measure of acid/base balance

Question 23

Paracetamol overdose: management

Answer 23

Central venous access and fluid replacement

Arrange for transfer to FRH

N-acetyl cysteine administration

Transfer to ITU

Intubation and ventilation

Question 24

Chronic liver failure: clinical presentation

Answer 24

Jaundice

Leuconychia

Clubbing

Palmar erythema

Gynaecomastia

Bleeding varices

ascites

umbilical hernia

dilated abdominal wall veins

Question 25

Chronic liver failure: management

Answer 25

Banding of varices Endoscopy Vitamins/nutrition Diuretics Liver screen Abdominal U/S

Question 26

Sub-acute liver failure

Answer 26

development of encephalopathy within 5 - 12 weeks of the onset of jaundice

Question 27

Hyper-acute liver failure

Answer 27

development of encephalopathy within 7 days of the onset of jaundice

Question 28

What are the clinical abnormalities (signs) of acute liver failure?

Answer 28

0-24 hrs: Patient may appear well – however nausea + vomiting 48–72 hrs: Anorexia, Right subcostal pain 72hrs+: Jaundice, Encephalopathy, Cerebral oedema

Question 29

Phase I of paracetamol OD

Answer 29

1 - 24 hours patient complains of nausea, vomiting and diaphoresis.

Question 30

Phase II of paracetamol OD

Answer 30

24 - 48 hours there may be no symptoms or clinical evidence of liver disease

Question 31

Phase III of paracetamol OD

Answer 31

2 - 10 days overt liver disease

Question 32

What causes jaundice seen in liver failure?

Answer 32

conjugation and excretion of bilirubin

Question 33

What causes encephalopathy?

Answer 33

metabolism of ammonia and detoxification of benzodiazepine like compounds

Question 34

What causes Ascites and oedema?

Answer 34

impaired synthesis of albumin

Question 35

What causes bruising?

Answer 35

impaired synthesis of clotting factors

Question 36

CAGE Questionnaire

Answer 36

Have you ever felt you should CUT down on your drinking? Have you ever felt ANNOYED by people criticising your drinking? Have you ever felt GUILTY about your drinking? Have you ever had a drink first thing in the morning? As an EYE OPENER

Question 37

Answer 37

Rigler’s sign gas either side of the lumen

Question 38

Answer 38

Small bowel obstruction Dilated \>3cm small bowel Centrally placed Valvulae conniventes are readily defined (coiled spring sign)

Question 39

Answer 39

large bowel obstruction

Question 40

Answer 40

calcification in the left kidney

Question 41

Causes of liver Cirrhosis (5)

Answer 41

Chronic infection Alcohol abuse Biliary disease Iron overload Autoimmune hepatitis

Question 42

Where is glutamine found?

Answer 42

Last 1-2hepatocytes scavenge any remaining ammonia