Starling's Forces & Fluid Compartments (E1)

Question 1

List the 3 Starling fluid compartments.

Answer 1

1) Plasma (90% H2O)
2) Interstitial fluid (90% H2O)
3) Intracellular fluid (70-85% H2O)

Question 2

Give the formula for net filtration pressure.

Answer 2

NFP = (Pc-Pi) - (πc-πi)

Question 3

What does variable Pc denote?

Answer 3

Capillary hydrostatic pressure

Question 4

What does variable Pi denote?

Answer 4

Interstitial hydrostatic pressure

Question 5

What does variable πc denote?

Answer 5

Capillary oncotic pressure

Question 6

What does variable πi denote?

Answer 6

Interstitial oncotic pressure

Question 7

List typical values you’d see on the NFP ARTERIAL end in the order Pc, Pi, πc, πi.

Answer 7

35, 0, 28, 5

Question 8

List typical values you’d see on the NFP VENULE end in the order Pc, Pi, πc, πi.

Answer 8

15, 0, 28, 5

Question 9

Movement across capillaries as a balance between hydrostatic and oncotic pressure gradients within the capillary and surrounding interstitium.

Answer 9

What are Starling’s forces?

Question 10

What does a positive NFP indicate?

Answer 10

Fluid LEAVING capillary

Question 11

What does a negative NFP indicate?

Answer 11

Fluid ENTERING capillary

Question 12

How do Starling’s forces govern movement across fluid compartments?

NOTE: 2 factors determine this

Answer 12

By determining the direction and amount of fluid exchange between the blood and interstitial fluid compartments