Physiology (Liver)

Question 1

What are the functions of the liver?

Answer 1

• Metabolic
• Immune
• Exocrine
• Coagulation
• Storage & blood capacitance

Read some more about it

Question 2

What are the functions of the liver?

Answer 2

• Metabolic
• Immune
• Exocrine
• Coagulation
• Storage & blood capacitance

Read some more about it

Question 3

Describe the hepatic blood flow ?

Answer 3

• 1,500mls (25% of cardiac output)
• About 75% is from portal vein
• About 25% from hepatic artery
• About 50% of O2 requirement in portal vein
• The rest of O2 is supplied by hepatic artery

Question 4

Oxygen saturation in the hepatic blood supply?

Answer 4

• Hepatic artery - 98%
• Portal vein - 70-85%

Question 5

What are the components of the hepatic triad?

Answer 5

• Hepatic artery
• Portal vein
• Bile duct

Question 6

Blood flow in the liver ?

Answer 6

Venous blood flows from right to left hepatic vein and drains into the IVC

Question 7

Mechanisms for regulation of hepatic blood flow?

Answer 7

• Intrinsic & Extrinsic - Hepatic artery
• Extrinsic only - Portal vein

Question 8

Regulation of hepatic artery blood flow ?

Answer 8

Intrinsic:
- Autoregulation
- Buffer response

Extrinsic:
- SNS
- Alpha & Beta receptors

Question 9

Regulation of portal vein blood flow ?

Answer 9

Extrinsic:
- Alpha receptor

Question 10

Other factors affecting hepatic blood flow ?

Answer 10

• Right heart
• Respiratory cycle

Question 11

Effect of the respiratory cycle on portal supply ?

Answer 11

• Inspiration = Increased portal flow
• IPPV = Decreased portal flow

Question 12

Factors affecting arterial supply?

Answer 12

• Reduction in cardiac output
• Anaesthesia
• Surgical retraction

Question 13

What are the causes of Jaundice ?

Answer 13

• Increased bilirubin production
• Impaired conjugation
• Congenital abnormalities
• Obstructed bilirubin drainage

Question 14

Effect of high bilirubin on general anaesthetic?

Answer 14

• Affects pulse oxymetry reading
• Risk of hepato-renal syndrome
• Myocardial depressant effect of bilirubin
• Neurotoxicity of bilirubin
• Bleeding

Question 15

Steps in primary haemostasis ?

Answer 15

• Muscular contraction of arterial wall
• Plug formation by platelet

Question 16

Steps in secondary haemostasis?

Answer 16

• Strengthening of plug by fibrin

Question 17

Coagulation pathway in injury ?

Answer 17

See and draw image

Question 18

What are the vitamin K dependent factors? “1972”

Answer 18

Factors;
X, IX, VII, II

Question 19

Draw the coagulation cascade?

Answer 19

See image attached