ICF N ECF

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ICF N ECF

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leen
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03/28/06 - 04:32 PM

A 35-year-old male is given 0.03 moles of thiocyanate intravenously to measure total extracellular water and 0.03 moles of I 131 albumin to measure plasma volume. After correcting for loses from the body, it is determined that the initial mixed concentrations of these substances in plasma were 0.008 mol/LI 131 albumin and 0.0015 mol/L thiocyanate.

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What is the volume of his extracellular compartment?

A. 5 L

B. 10 L

C. 15 L

D. 20 L

E. 25 L

robin082006
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03/28/06 - 04:47 PM

D

=0.03/0.0015=20l

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vanshita
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03/29/06 - 07:04 AM

leen
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03/29/06 - 12:26 PM

yeah D is the right ans

cool_guyp4u
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03/30/06 - 05:03 PM

robin082006 wrote:
D

=0.03/0.0015=20l

Hi robin and others,

how did you come up with the calculation?

simi
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04/11/06 - 05:32 PM

can anyone explain the calculation please? shaking head

doc179
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04/11/06 - 07:01 PM

the formula used here is V * C = A
V = volume of the compartment to be measured
C = concentration of the substance injected in that compartment
A = the amount of substance injected

the Q asks what is V.
V = A/C = 0.03 moles/ 0.0015 mol/ltr = 20 L

simi
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Topics: 53
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04/13/06 - 04:16 PM

thank u doc179 smiling face

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