Tissue Fluid and Oedema

Question 1

what does blood flow in capillaries depend on?

Answer 1

contractile state of arterioles

Question 2

how fast is the blood flow through capillaries described?

Answer 2

slow (allows time for exchange of substances)

Question 3

how are exchangeable protein moved across capillaries?

Answer 3

vesicular transprt

Question 4

how are hydrophilic substances eg Na+ moved across capillary walls?

Answer 4

through the water-filled pores?

Question 5

how are lipid soluble substance moved across capillary wall? eg O2

Answer 5

diffusion across endothelial cell

Question 6

why can plasma proteins not pass the capillary wall?

Answer 6

they are large molecules

Question 7

what does NFP stand for?

Answer 7

Net filtration pressure

Question 8

how is NFP calculated?

Answer 8

forces favouring filtration- forces opposing filtration

Question 9

what are the forces favouring filtration?

Answer 9

capillary hydrostatic pressure

interstitial fluid osmotic pressure

Question 10

what are the forces opposing filtration?

Answer 10

capillary osmotic pressure

interstitial fluid hydrostatic pressure

Question 11

during a day is there more reabsorption or filtration?

Answer 11

filtration exceeds absorption by 2-4 litres

Question 12

how is excess fluid returned to the circulation?

Answer 12

lymphatic system

Question 13

what is Oedema?

Answer 13

accumulation of fluid in interstitial spaces

Question 14

what is the problem with pulmonary oedema?

Answer 14

causes less gas exchange as the fluid increases the diffusion distance

Question 15

what is the main physiological cause of Oedema?

Answer 15

raised venous pressure

Question 16

what can pulmonary oedema be a sign for?

Answer 16

left heart failure

Question 17

what can peripheral oedema be a sign for?

Answer 17

right heart failure

Question 18

how does heart failure effect the Frank-Starling curve?

Answer 18

shifts it right (even with treatment)

stroke volume is decreased

Question 19

what clinical exam findings suggest pulmonary oedema?

Answer 19

some shortness of breath
crepitations heard on auscultation if lung bases
CXR shows haziness in perihilar region

Question 20

what is the definition of Pulmonary Oedema?

Answer 20

accumulation of fluid in the interstitial and intra-alveolar spaces

Question 21

what biological things can cause Oedema?

Answer 21

lymphatic insufficiency

changes in capillary permeability (eg due to inflammation), reduced plasma osmotic pressure