Fluid Balance & Electrolytes Flashcards
we give ________ to pregnant women who go into labor early or have preeclampsia
magnesium
older adults are more prone to dehydration/have a lower total body water because of…
loss of muscle and fat, which hold water
2/3 of body water is in the…
intracellular space
1/3 of body water is in the…
extracellular space
20% of ECF is ______ and 80% is ________
plasma
interstitial fluid
movement of water is based on _______ and ________
osmosis and net filtration
osmosis: “water follows _____”
“salt” (or other solutes in high concentration)
isotonic, hypertonic, hypotonic
isotonic = normal hypertonic = higher concentration outside cell hypotonic = lower concentration outside cell
hypotonic solutions lead to…
cellular edema
causes rough ER to lose ribosomes
decrease in protein synthesis
hypertonic solutions lead to…
crenation
cell shrinks up and dies
we may give hypertonic solutions to patients who…
need blood volume STAT
net filtration regulates exchange between which 2 compartments?
interstitial
vascular
net filtration affected by which pressures?
hydrostatic
oncotic
hydrostatic pressure moves water…
out of capillaries
oncotic pressure
osmotic pressure generated by presence of proteins/solutes
hypernatremia drawing water from the interstitium into the vascular compartment is an example of ______ pressure
oncotic
which capillaries have high/low water permeability?
high - glomerulus
low - brain capillaries
function of lymphatic system r/t fluid balance
Returns large volumes of fluid from interstitial space to intravascular space
blood volume (increases/decreases) if the lymphatic system fails
decreases
edema
excessive amount of fluid in the interstitial space
flesh holds its shape when you squish it down
pitting edema
etiology of edema (4)
Increased capillary hydrostatic pressure (BP)
Obstruction of lymphatic circulation
Increased capillary permeability
Certain bacterial toxins or large burn wounds
pink frothy sputum can indicate…
pulmonary edema
lymphedema
edema associated c failure of lymphatic system
what can increase capillary permeability, leading to edema?
histamines & other inflammatory mediators
what is edema resulting from increased capillary permeability associated with?
inflammation/infection
edema of face mainly
beneath the skin
almost entirely caused by medications, allergies, or autoimmune response
angioedema
s/s of edema (7)
local skin change functional impairment/decreased ROM pain impaired arterial circulation pitting increased body weight dental complications
Compartment syndrome
what is it a concern with?
swelling does not allow bloodflow through
casts
third-spacing
Fluid shifts into a body cavity & cannot re-enter blood or be used again
example of third-spacing
ascites
hormone released in response to high blood volume
natriuretic peptide
how do the effects of natriuretic peptide affect fluid balance? what is the goal?
goal: decrease blood volume
decreases aldosterone - leads to diuresis
decreases ADH - leads to diuresis & decreased thirst
dehydration
excessive loss of body water
sites for turgor test
child - abdomen
adult - back of hand
elder - infraclavicular skin
tenting indicates…
dehydration
risk factors for dehydration (6)
extremes of age (young, old) decreased fluid intake excessive fluid output chronic disease acute illness medications
clinical manifestations of dehydration (12)
Hypernatremia Inability to tear Decreased urine output Elevated urine specific gravity Sunken fontanels (babies) Try mucous membranes Decreased skin turgor Lower BP Weak pulse Fatigue Increased hematocrit Decreased mental function
between natriuretic peptide and RAAS, which responds to low BP? which to high blood volume?
high blood volume - natriuretic peptide
low BP - RAAS
5 ways body responds to dehydration
Increased thirst Increased HR - needs to rise because volume has decreased Constriction of cutaneous blood vessels Less urine production RAAS
function of RAAS
increases BP
____ secreted by kidney in direct response to decreased blood flow to kidney
renin
renin activates _______
angiotensin
2 effects of angiotensin
vasoconstriction
triggers aldosterone production
effects of aldosterone
Na+ retention
draws water into vascular space
3 effects of ADH
vasoconstriction
water retention
increased thirst
electrolytes
minerals in the body that have an electrical charge
4 extracellular electrolytes
Na+
Ca+
HCO3-
Cl-
intracellular electrolytes
K+
Mg+
P-
Na/K pump function
uses ATPase to maintain normal distributions of Na and K
Pumps 3 Na out for every 2 K in
Na+ functions
cellular excitation
ECF fluid volume maintenance
K+ function
muscle contraction
nerve conduction
renal function
Ca+ functions
muscle & nervous excitation
membrane permeability
exocrine, endocrine, neurocrine function
Mg+ functions
activation of enzyme systems
role in ATP production
regulation of Ca actions
Cl- function
acid-base balance
P- function
buffer system cellular metabolism (atP)
