objective 4 (1) Flashcards
what are the principles of fluid and electrolyte balance?
- Necessary for life and homeostasis
- Nursing role is to help prevent and treat fluid and electrolyte
disturbances
- State of equilibrium in body
- Naturally maintained by adaptive responses
- Body fluids and electrolytes are maintained within narrow limits
homeostasis
what is the % of water content of the body?
- 50% to 60% of body weight in adult
- 45% to 55% in older adults
- 70% to 80% in infants
inside the cell
intracellular fluid
outside a cell
extracellular fluid
Normal distribution of fluid in ICF and ECF
first spacing
Abnormal accumulation of interstitial fluid
second spacing
loss of ECF into a space that does not contribute to
equilibrium
third spacing
cations that carry a positive charge and anions
that carry a negative charge
active chemicals
what are the major cations?
sodium, potassium, calcium, magnesium and
hydrogen ions
what are the major anions>
chloride, bicarbonate, phosphate, sulfate and
proteinate ions
what is the major cation in ECF?
sodium (Na+)
what is the normal for sodium?
134-145 mmol/L
what is the major cation in ICF?
potassium K+
what does the movement of fluid through capillary walls depend on?
- Hydrostatic pressure
Pressure exerted on the walls of blood vessels - Osmotic pressure
Pressure exerted by the protein in the plasma
movement of water between 2 compartments
osmosis
movement of a substance from an area of higher concentration to
one lower concentration (ions and molecules - eg O2 and CO2)
diffusion
movement of water and solutes from high hydrostatic pressure to
low hydrostatic pressure (eg kidney filtering lymph)
filtration
energy is expended for the movement to occur against a
concentration gradient
12
active transport
what is the average fluid intake?
2500mL/day
what is the average fluid output?
1500mL/day Urine
100mL/day bowels
- Dietary intake of fluid and food or enteral feeding
- Parenteral fluids (IV)
fluid gain