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Author8 Posts
  #1

The following pulmonary pressures (in mm Hg) were measure in an animal who was breathing spontaneously:

Hydrostatic capillary pressure: 12
Oncotic capillary pressure: 20
Hydrostatic interstitial pressure: -5
Oncotic interstitial pressure: 15

The filtration coefficient of the pulmonary microvasculature is 1mL/min/100g tissue/mm Hg pressure, and the reflection coefficient for protein is 1. Which of the following best represents the magnitude and direction of fluid flux in this animal?

A) Magnitude: 2mL/min, Direction: capillary to interstitial space
B) Magnitude: 2mL/min, Direction: interstitial space to capillary
C) Magnitude: 12mL/min, Direction: capillary to interstitial space
D) Magnitude: 12mL/min, Direction: interstitial space to capillary
E) Magnitude: 22mL/min, Direction: capillary to interstitial space
F) Magnitude: 22mL/min, Direction: interstitial space to capillary


  #2

C?


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  #3

i think C too

  #4

I think C as well ... Can the Clar Enlighten us ?

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  #5

Can anyone explain this prob to me?i did not understand.

  #6

cap fluid exch

P net = (Pc -Pi) - (Mc-Mi)
ie (12- -5) -(20-15)
17- 5
=12

  #7

luckyme wrote:
Can anyone explain this prob to me?i did not understand.



there r two events opposite in direction occurs in the capillary: filtration and reabsorption

what favours filtration is 2 factors : capillary hydrostatic pressure and interstitial osmotic pressure .....in this problem the sum is 27 mmhg

what favours reabsorption is : interstitial hydrostatic pressure and capillary osmotic pressure...in this problem the sum is 15 mmhg

so net result is filtration of12mmhg

now the question states that the filtration coeffecient is 1ml/min/mmhg


so the answer is 12ml/min/mmhg

if the coeffecient was 2ml/min/mmhg the answer would be 24

and so on

  #8

Answer is C

{12-(-5)}-(20-15)

= 17-5

= 12










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