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Key terms for Fluid and Electrolytes
Term:
Intracellular fluid:
Extracellular fluid:
Interstitial fluid:
Intravascular fluid:
Osmolality:
Starling’s Law of Capillary Forces:
Filtration:
Reabsorption:
Hydrostatic Pressure:
Osmotic pressure:
Oncotic pressure:
Edema:
Generalized edema:
Localized edema:
Pitting or dependent edema:
Hypertonic solution:
Hypotonic solution:
Isotonic solution:
Description:
Contained within the cell. 2/3 of total body water.
Fluid outside of the cells. 1/3 total body water. Two
compartments; interstitial fluid and intravascular
fluid.
Fluid between cells, outside of the blood vessels.
Blood plasma or fluid within the blood vessels.
The number of particles of a solute in a unit of
solution. Serum osmolality is 280-310 mOsm/kg.
The movement of fluid that occurs at every capillary
bed using hydrostatic pressure and osmotic pressure
(which includes oncotic pressure)
Movement of both water and smaller molecules
through a semi-permeable membrane from an area of
high pressure to an area of low pressure.
Fluid shifting back into the capillary from the
interstitial space.
Pressure exerted by fluid within a closed system such
as intravascular space. Leads to movement
(filtration) of water through the capillary membranes
into the interstitial space.
Power of a solution to attract water due to
concentration. The concentration is through solutes
in the solution. In the bloodstream, the concentration
is created by electrolytes, nutrients and proteins.
Also called colloidal oncotic pressure. Refers to the
force exerted specifically by albumin in the
bloodstream. Good fact to know is that albumin is
indicative of the protein nutritional status of the body
so low albumin means poor nutritional status
Accumulation of fluid within the interstitial space
and intercellular fluid
Palpable swelling produced by expansion of the
interstitial fluid volume; when massive and
generalized, the excess fluid accumulation is called
anasarca
Increased interstitial fluid at a specific sight,
generally due to trauma
Due to gravity pressure on tissue, generally see in the
extremities of the legs
More particles (solutes) than the blood, less water
Fewer particles (solutes) than the blood, more water
Same tonicity of the blood. We use 0.9% normal
saline or 305 mOsm/kg
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Intake:
Output:
The amount of fluid a person takes into their body
within a day is about 2400-3200ml, generally
>1500mL for normal kidneys to function and 5001000mL from food.
The amount of fluid that leaves the body within a
day. Obligatory output should be 300-500mL/day or
around 30-40mL/hr. Insensible water loss is about
100mL/day more if you have a fever