Ch. 41 Fluid and electrolyte, and acid-base balance Flashcards
(35 cards)
water
- the most abundant substance in our bodies, 60% of adult weight
- 80% in infants
- men have more water
distribution of body fluids
-intracellular fluids: within cells of body
-extracellular fluids: All fluids outside a cell.
+interstitial fluids
+intravascular
+transcellular
electrolytes
- regulates fluids balance and hormone productions
- strengthen skeletal structures
- acts as catalysts in nerve response, muscle contraction and metabolism
- electrolytes are present in all body fludis
Composition of body fluids definitions
- solute: Electrolytes, oxygen, carbon, dioxide, glucose, proteins
- solvent: water in the body
- minerals: iron, zinc
Flids and solutes move across these membranes by 4 processes
Osmosis:
Diffusion:
Filtration:
Active transport:
osmosis
the movement of a pure solvent across a semipermiable membrane from an area of lesser solute concentration to an area of greater solute concentration
-the membrane is permeable to the solvent, but it impermeable to the solute
hypertonic
solution high in osmotic pressure (cell shrinks)
IV solution: 3% sodium chloride
Isotonic
solution with the same osmolarity as blood plasma
IV solutions: normal saline, 0.9% sodium chloride
Hypotonic
solution is lower osmotic pressure (CELL ENLARGES)
-IV solution: 0.45 sodium chloride
Diffusion
from an area of higher concentration to an area of lower concentration
filtration
water and diffusible substances move together across a membrane, in response to fluid pressure, moving from an area of high pressure to on of lower pressure
active transport
- requires metabolic activity
- ex. transport of sodium-potassium-ATPase pump
Hypovolemia
Cause: Gi losses, skin losses, renal losses, hemorrhage, altered intake
SUBJ&OBJ data:
-VS: hyperthemia, tachycardia, thready pulse, hypo-tension, tachypnea, hypoxia
- Neuromusculoskeletal: dizziness, syncope, confusion, weakness, fatigue
- GI: thirsty, dry furrrowed tounge, dry mucous mme
Dehydration
causes: hyperventilation, diabetic, enternal feeding
subj, obj, data: same as hypovelmia
Hypervolemia
cause: chronic stimuli to the kidney to conserve sodium and water, age related, excessive sodium intake
subj. & obj data:
- VS: tachycardia, bounding pulse, hypertension, tachypnea
- Neuro: confusion, muscle weakness
- GI weight gain
avg adults intake
2200-2700 ml per day
Renin
secreted by kidneys, responds to a decrease renal perfusion secondary to a decrease renal perfusion secondary to a decrease in extracellular volume.
angiotensin II
-vasoconstriction
aldosterone
released by the adrenal cortex.
- counteracts hypovolemia
- acts as a volume regultor
atrial natriuretic peptide (ANP)
acts as a diuretic that causes sodium loss and inhibits the thirst mechanism
fluid output occurs through 4 organs
- kidneys (major regulatory organs)
- skin
- lungs
- GI tract
insensible
water loss occurs through the skin and lungs. A person does not perceive the loss
Sensible
water loss occurs through excess perspiration and can be perceives by the client
- an avg of 500-500 ml of sensible and insensible fluid is lost via skin each day
- 500 ml through lungs
cations
sodium, potassium, calcium, and magnesium
