Fluid balance

Question 1

What is osmolarity?

Answer 1

Conc of solute particles
Na+ extracellular
K+ intracellular
Water will move towards areas of high solute conc

Question 2

What are the components of extracellular fluid?

Answer 2

Extravascular/interstitial fluid - fluid between cells
Intravascular
fluid

Question 3

Describe the components of extracellular fluid

Answer 3

Proteis
Na+
Cl-
HCO3-
Capillary membrane freely permeable to water and electrolytes

Question 4

Describe the components of intracellular fluid

Answer 4

K+
Cell membrane freely permeable to water only

Question 5

What are starling’s forces?

Answer 5

Hydrostatic pressure
Oncotic pressure
Osmotic pull
Permeability

Question 6

What is osmotic pull/force

Answer 6

Water diffused from area of highest conc of water to area of lowest conc of water

Question 7

What is hydrostatic pressure

Answer 7

Force that results from the pressure of a liquid (water) within a compartment

Question 8

What is oncotic/colloid pressure?

Answer 8

induced by proteins which look to pull water back into plasma - opposite to hydrostatic pressure

Question 9

Describe the balance of forces that balances water movement in and out of capillaries

Answer 9

Question 10

Define tonicity

Answer 10

osmotic pressure of solution relative to the plasma
isotonic = same osmotic pressure as plasma

Question 11

Define osmolarity

Answer 11

conc of particles dissolved in a fluid per L

Question 12

Define osmolality

Answer 12

Conc of particles dissolved in a fluid per kg

Question 13

If osmotic pressure/osmolarity is too high in the plasma where will fluid flow?

Answer 13

into plasma

Question 14

If a solution is hypertonic what is its concentration compared to plasma?

Answer 14

more concentrated

Question 15

What is an effective osmole?

Answer 15

a solute that does not freely cross the membrane, e.g., Na+, K+

Question 16

What is an ineffective osmole?

Answer 16

a solute that freely crosses the membrane e.g., glucose, urea