Fluid COmpartments -Block3 Physi

Total body water (TBW) varies from

50-70% of body weight

In an average person, the total body water weight will be

42L (42kG)

The density of water is

1Kg per 1L

Where would you find the body water?

EVERYWHERE! but mostly in the muscle followed by the skin

How much of the total body weight is in the intracellular

40%

How much of the BDWter is in the extracellular

20%

The plasma of the blood makes up ___% of the ECF

25

Interstitial is __% of the ECF

75

How to measure the size of compartments

compartment volume = amount injected / final concentration

Labeled water is the best marker for

water

IF you want to measure a specific compartment, what would you do?

find a marker (such as insulin for ECF)

If you want to measure the total body water, then you need to

find a marker that will cover all compartments

Osmolarity measures

osmoles of solute particles

Molarity measures

moles of solute

Osmole

a unit of osmotic pressure equivalent to the amount of salute that dissociates in solution from one mole of particles

1 mole of NaCl is equal to __ osmoles

2

In plasma electrolytes, there is approx. ___ osmoles/L of H2O

300

Osmolality is measured with what units

millimoles of solute/Kg of H2O

Osmolarity is measured with what unit

millimoles of solute/L of H2Oa

activity of H2O decreases as ____ increases

osmolality

Colligative properties of solutions depend on

boiling point, freezing point, vapor pressure and osmotic pressure

Major cation in the ECF

Na+

Major anion is ECF is

Chloride and bicarbonate

major component of cation is ICF

potassium

Major component of anion in ICF

phosphate

The three major compartments

Capillary, interstitium, and intracellular

The capillary is

permeable to most solutes but impermeable to large proteins

The intracellular compartment is

impermeable to most solutes

The total body content of ____ is the principal determinant of extracellular and intravascular fluid volume

sodium

ALl of the Na+ ions and anions will go to the

ECF

Potassium ions and anions will go to

ICF

D5W is basically

water with 5% glucose (adds no effective osmoles)

At equilibrium, all compartments will have the same

osmolality

Which fluid compartment will increase the most if you infuse KCl?

ICF

What IV solution should you give an 80 year old who has had nothng to drink for 3 days?

D5W

What IV solution would you give an infant with vomiting and diarrhea for 2 days

Normal Saline

What IV solution would you give to a gunshot wound victim?

Blood and Plasma