I. FLUID/ELECTROLYTE BALANCE
a. Categories of changes (is a lot of overlap)
i. Volume--involve ECF compartments (vascular and interstitial spaces)
1. Equal changes in _________ and _________ (iso-osmotic changes)
2. Changes in BP are common
3. Ex- lose of blood because of trauma
ii. Osmotic--affect ICF
1. Unequal changes of Na and water
2. Osmolarity is the same in all compartments because of the movement of water
3. Cells like neurons don’t like to work as ___________
4. Ex- dehydration
iii. Compositional--ions other than Na
1. ___ , ______ are most common cations
b. Electrolyte balance (anything with a charge)
i. Involve, sodium, chloride, potassium, calcium, hydrogen
ii. Water cannot be ignored because electrolytes are dissolved in water
iii. Hormones involved are primarily ______ , ________ (renin [enzyme], AT I, AT II)
c. Balance of water involves both ________ and ________ pressures
i. Hydrostatic P is fluid (blood, interstitial fluid) pressure
ii. Osmotic P depends on molecules (proteins) that are trapped on one side of cell
membrane and is 1° determined by proteins (colloid osmotic pressure, oncotic
pressure)
iii. Tonicity—isotonic (287 mOsm/L), hypotonic, hypertonic
1. Individuals normal isotonic pressure varies
2. Water always moves into the ________ __________ (there are more osmotic
particles and you have to dilute them)
d. Terms used with water/fluid balance
i. Edema---Accumulation of xs fluid in interstitial space
1. ______ hydrostatic capillary pressure or permeability
2. ______ colloid pressure in blood vessels
3. ______ colloid pressure in the interstitial space
4. Lymphatic obstruction/ vasodilation
5. Sodium/ water excess
6.
a. Pitting edema
