Abdominal Vasculature - Part 3

Question 1

What kind of flow occurs in the proximal IVC?

Answer 1

Complex pulsatile flow

Question 2

What does the complex pulsatile flow of the proximal IVC a result of?

Answer 2

Variations in the intra-abdominal pressure associated with respiration and regurgitation of blood from the right atrium during atrial systole

Question 3

What is the proximal IVC influenced by?

Answer 3

The right atrium

Question 4

What kind of flow occurs in the distal IVC?

Answer 4

Phasic flow

Question 5

What does the distal IVC reflect from?

Answer 5

Peripheral veins

Question 6

Which portion of the IVC is affected less by cardiac activity?

Answer 6

The distal portion

Question 7

What kind of flow occurs in the hepatic veins?

Answer 7

Pulsatile

Question 8

What does the hepatic vein reflect on? (2)

Answer 8

1. Cardiac activity

2. Respiratory activity

Question 9

What flow is similar to the hepatic veins?

Answer 9

The IVC

Question 10

What are the 3 phases in the hepatic veins? (2)

Answer 10

1. Two toward the heart
   - reflection of the right arterial and ventricular diastole
2. One away from the heart
   - represented by systolic flow which is caused by contraction of the right atrium

Question 11

What kind of flow occurs in the hepatic veins?

Answer 11

Hepatifugal flow

Question 12

Hepatifugal flow

Answer 12

Flow away from the liver

Question 13

What is the shape of the hepatic vein waveform?

Answer 13

W shape

Question 14

What do the hepatic veins drain?

Answer 14

The entire liver

- except the caudate lobe

Question 15

What drains the caudate lobe?

Answer 15

The IVC

Question 16

Do hepatic veins contain valves?

Answer 16

No

Question 17

What kind of flow occurs in the portal vein? (2)

Answer 17

1. Minimally phasic

2. Low peak and mean velocities

Question 18

What is the velocity of the portal vein in supine/fasting patients?

Answer 18

20-30 cm/s

Question 19

What kind of flow occurs in the portal veins?

Answer 19

Hepatopedal flow

Question 20

Hepatopedal flow

Answer 20

Flow towards the liver

Question 21

How does intra-abdominal pressure effect the portal vein?

Answer 21

Respiration that are transmitted through the liver to the portal and splenic veins
- causing an undulating flow pattern in the portal venous system

Question 22

How much of the portal vein and its tributaries are responsible for the oxygenated blood supply of the liver?

Answer 22

70%

Question 23

When does portal venous flow normally accelerates?

Answer 23

During expiration

Question 24

When does portal venous flow normally decelerate?

Answer 24

During inspiration

Question 25

What is portal venous flow affected by? (3)

Answer 25

1. Posture
2. Exercise
3. Dietary state

Question 26

What do exercise and postural changes usually cause in the portal system?

Answer 26

A decrease in portal venous flow

Question 27

What does eating usually cause in the portal system?

Answer 27

It will increase flow as a result of splenic vasodilation and hyperaemia

Question 28

What 2 things make up the portal vein?

Answer 28

1. SMV

2. Splenic vein

Question 29

What is the normal blood velocity for the portal vein?

Answer 29

13-23cm/s

Question 30

What is the average blood velocity for the portal vein?

Answer 30

18cm/s

Question 31

What kind of flow occurs in the renal veins?

Answer 31

Phasic flow

Question 32

What are the flow patterns of the renal veins influenced by?

Answer 32

The systemic circulation

- for this reason, they do not exhibit pulsatility associated with atrial or ventricular contraction

Question 33

Which renal vein is longer?

Answer 33

The left one