fluid imbalance Flashcards
Intracellular space/fluid
2/3 of water in body
Primarily electrolytes (K,PHOS, MAG)
Extracellular space/fluid
Both plasma (in the vessel) and interstitial fluids
Also lymph/transcellular fluids
Primarily electrolytes (NA, CL, HCO3)
What is different about the fluid % in older adults?
Lower %
Osmosis
Diffusion of water (concentration gradient)
Hydrostatic/osmotic pressures
pressure on blood vessel walls/ proteins in the blood(albumin)
The albumin attracts water to prevent it all from leaving
Diffusion
Solutes move from higher concentration to lower
How to gain fluids
PO mostly
Or IV
How to lose fluid
Kidneys (mostly)
Skin loss from sweat, burns, fever
Lungs from breathing, tachypnea
GI tract from stools
Third spacing
Fluid outside of the cells and blood vessels.
Due to there being too much fluid in cells
This is how we get edema
Symptoms of low intravascular volume:
tachycardia
hypotension
low urine output
edema
Urine specific gravity (test)
Shows how concentrated the urine is
Hematocrit (test)
Concentration/percentage of RBC’s
BUN blood urea nitrogen (test)
Concentration of urea (waste product) in the blood
***fluid volume deficit AKA hypovolemia
low volume in blood vessel
causes:
fluid loss
low intake
***fluid volume deficit
older adults higher risk
change related to agine, thirst, response
medication AE (diuretic)
intentional reduce fluid intake (at night to preventing having to pee in the middle of the night)
***Fluid volume deficits
S/S
BP decrease
HR increase
Dry mucus membranes
Decreased urine output
Decreased skin turgor
Dizziness
Thirst
Late sign: neuro changes
***Fluid volume deficit
Lab findings
Concentration increases:
Increased BUN
Increased Hematocrit
Increased urine osmolality
***Fluid volume deficit
Interventions
Oral or IV fluid replacement
Be cautious with rate with: older adults, renal disease, heart failure (can cause fluid overload)
Strict I/O
Daily weight
Monitor pulse and BP (want pulse to decrease and bp to increase)
Treat nausea, diarrhea, fever (all cause decrease fluids)
Oral care
***Fluid volume excess
Causes:
-Excessive intake (rare)
-Excess intravascular fluid
-Heart failure
-Renal failure
***Fluid volume excess
S/S
Weight gain
JVD distention
Dyspnea/crackles
Edema
Late sign: LOC changes
***Fluid volume excess (lab findings)
Sodium low <135
BUN low <8
Specific Gravity <1.010
Chest x-ray: pulmonary congestion (can see fluid on x-ray)
***Fluid volume excess
Interventions
Fluid restriction
Diuretics
Compression stockings if lower edema
Elevate HOB
I/O
Daily weight
Monitor: JVD, Urine output
Third spacing
Fluid goes into interstitial third space
Fluid not in vessels or cells
Cause:
Liver failure
Burns
Trauma
Severe inflammation/sepsis
Third spacing S/S
Symptoms of hypovolemia with profound edema
This is due to fluid leaving the vessel and entering the third space causing edema but also s/s of hypovolemia
Third spacing treatment
Difficult to treat
May need paracentesis
May need administration of albumin (protein that draws the fluid back into the vessel)
Compression stockings for lower edema
***Isotonic
Tonicity similar to plamsa
Expands ECF (fluid stays in blood vessels)
Used for ECF volume deficit (dehydration from vomiting)
***Isotonic fluids
0.9% Sodium Chloride (NS)
Lactated ringers (LR) *avoid use in hyperkalemia (contains K), matabolic alkalosis (PH>7.5)
***Hypotonic
Low osmolality, water moves into the cell
Can lead to excess icf (cellular edema)
Referred to as hippotonic bc cells get big a fat
***Hypotonic fluids
0.45% NACL (aka 1/2 ns)
D5W
Give these slow (maintenance replacement fluid)
***Hypertonic
Cells shrink bc vessel draws fluid in
Higher osmolality, draws fluid from cells to ecf (into vessels) very concentrated
*can cause fluid overload in vessels
Used for patients with cerebral edema, hyponatremia
***Hypertonic fluids
3% NACL
D10W/D15W (10-15% DEXTROSE in water)
*requires frequent monitoring can cause rapid shifts in fluid, cell shrinkage
***Main differences in iso, hyper, hypo
Isotonic: no change
Hypotonic: cell swells
Hypertonic: cell shrinks
