2: Oedema - fluid shift across capillary walls

Question 1

What acts as a go-between the blood and body cells?

Answer 1

Interstitial fluid

Question 2

What is interstitial fluid?

Answer 2

Extracellular fluid which bathes body cells

Question 3

Capillaries are made up of a ___ layer of ___ cells.

Answer 3

single , endothelial

Question 4

Capillaries allow for rapid exchange of gases, water and solutes with the ___ ___.

Answer 4

interstitial fluid

Question 5

Blood flow in the capillaries depends on the contractile state of ___.

Answer 5

arterioles

Question 6

Arterioles regulate the blood flow to ___.

Answer 6

capillaries

Question 7

How is blood flow in the capillaries adapted to allow adequate time for exchange?

Answer 7

Blood flow is very slow

Question 8

Why can the heart extract 75% of oxygen from the blood?

Answer 8

It has a rich capillary network to allow for exchange, and lots of mitochondria which use the oxygen

Question 9

Electrolytes, glucose and amino acids (can / cannot) pass through the capillary wall.

Answer 9

can

Question 10

Hydrophilic substances pass through capillary walls by ___.

Answer 10

diffusion

Question 11

Plasma proteins (can / cannot) pass through the capillary wall.

Answer 11

cannot

Question 12

Fluid movement follows which kind of gradient?

Answer 12

Pressure gradient

Question 13

Lipid soluble substances (pass / do not pass) through endothelial cells.

Answer 13

pass

Question 14

How do hydrophilic substances pass through capillary walls?

Answer 14

Water-filled pores

Question 15

Transcapillary fluid flow is driven by ___ ___ across the capillary wall.

Answer 15

pressure gradients

Question 16

Give an equation for Net Filtration Pressure (NFP).

Answer 16

NFP = Forces favouring filtration - forces opposing filtration

Question 17

What, other than the NFP, affects transcapillary fluid flow?

Answer 17

Filtration coefficient (Kf)

Question 18

Across which kind of vessel does resistance to blood flow greatly drop?

Answer 18

Arterioles

Question 19

A positive NFP indicates that (filtration / reabsorption) will occur in the vessel.

Answer 19

filtration

Question 20

A negative NFP indicates that (filtration / reabsorption) will occur in the vessel.

Answer 20

reabsorption

Question 21

Starling forces favour ___ at the arteriolar end and ___ at the venular end.

Answer 21

filtration , reabsorption

Question 22

Starling forces favour reabsorption at the __ end and filtration at the __ end.

Answer 22

venular , arteriolar

Question 23

Starling forces favour reabsorption at the __ end and filtration at the __ end.

Answer 23

venular , arteriolar

Question 24

The major force favouring filtration is the…

Answer 24

CAPILLARY HYDROSTATIC PRESSURE

Question 25

The major force opposing filtration is the...

Answer 25

CAPILLARY OSMOTIC PRESSURE

Question 26

During a day, ___ tends to exceed ___.

Answer 26

filtration , reabsorption

Question 27

How is excess fluid in the interstitium returned to the circulation?

Answer 27

Through the lymphatic system as lymph

Question 28

Pulmonary resistance is around __% of systemic resistance.

Answer 28

10%

Question 29

In the pulmonary system, which force is greater? Pulmonary capillary hydrostatic pressure (filtration) Pulmonary capillary osmotic pressure (absorption)

Answer 29

Pulmonary capillary osmotic pressure (absorption) So accumulation of interstitial fluid is usually prevented.

Question 30

What is oedema?

Answer 30

Accumulation of fluid in the interstitial space

Question 31

What is compromised in pulmonary oedema - why?

Answer 31

Gas exchange The distance diffusion has to take place over increases due to swelling

Question 32

One cause of oedema is ___ capillary pressure.

Answer 32

raised

Question 33

In oedema caused by raised capillary pressure, arteriolar ___ causes the venous pressure to ___.

Answer 33

dilatation , increase

Question 34

What kind of oedema occurs in patients with left ventricular failure?

Answer 34

Pulmonary oedema

Question 35

What kind of oedema occurs in patients with right ventricular failure?

Answer 35

Peripheral oedema (ankle, sacral)

Question 36

What cause of raised venous pressure, other than ventricular failure, results in oedema of the ankles?

Answer 36

Prolonged standing

Question 37

Heart failure shifts the Frank-Starling curve to the...

Answer 37

right.

Question 38

Another cause of oedema is ___ plasma osmotic pressure.

Answer 38

reduced

Question 39

What is the normal concentration of plasma proteins in the blood?

Answer 39

65-80g/L

Question 40

At what threshold of [plasma protein] will plasma osmotic pressure fall low enough for oedema to start?

Answer 40

< 30g/L

Question 41

What is a lymphatic cause of oedema?

Answer 41

Lymphatic damage

Question 42

What kind of oedema is associated with lymph node damage?

Answer 42

Pitting oedema

Question 43

Oedema can also result from changes in capillary ___.

Answer 43

permeability

Question 44

What events can cause changes in capillary permeability - why?

Answer 44

Inflammation caused by pro-inflammatory mediators - histamine, bradykinin - causes leakage of protein

Question 45

Pulmonary oedema is the accumulation of fluid in the ___ and ___ lung spaces.

Answer 45

interstitial , intraalveolar

Question 46

What is the main symptom of pulmonary oedema?

Answer 46

Shortness of breath

Question 47

What would you find on auscultation of the lung bases of a patient with pulmonary oedmea?

Answer 47

Crepitations in the lung bases

Question 48

What would be seen in the CXR of a patient with pulmonary oedema?

Answer 48

Haziness in hilum area

Question 49

Where is pitting oedema found?

Answer 49

Ankles, sacrum