Body water and compartments Flashcards
1
Q
What percentage is total body water?
A
60%
2
Q
- Intra-cellular fluid
- amount of TBW?
- What is it?
- Extra cellular fluid
- Amount of TBW?
- 4 components?
A
- ICF
- 2/3 total body water
- fluid within the cells
- ECF
- 1/3 total body water
- reduces with age
- Intravascular:
* 4L, 9.5% TBW, 7% body weight
- Intravascular:
- Interstitial
* 9L, 21% TBW, 13% body weight
- Interstitial
- Transcellular
* 1L, 2% TBW, .5% body weight
- Transcellular
- Bone and connective tissue
* 1L, 2% TBW, 1.5% body weight
- Bone and connective tissue
3
Q
Intravascular fluids compartment - what is it made of?
A
- plasma (55%)
- straw coloured fluids containing cells
- 70-75ml/kg (5L)
- water (90%)
- proteins (7%) -> oncotic pressure
- Albumin 60%
- Globulins (α, β, γ) 35%
- Fibrinogen 4%
- ions
- Blood cells -> ICF
4
Q
Interstital fluid
A
- Largest component of ECF (10L)
- surrounds cells
- acts as a transport medium between the ICF and intravascular fluid for fluid, nutrients, oxygen and waste products
- Same composition as plasma - proteins = same osmolality
- Fluid administered into the vascular space is freely exchanged with the ISF
5
Q
Transcellular fluids
examples
A
- Fluid which has been secreted but is separated from the plasma by an epithelial layer
- Gastrointestinal tract (GIT) fluid
- Cerebrospinal fluid (CSF)
- Bladder urine
- Aqueous humor
- Bile
- Sweat
6
Q
Osmosis
Osmotic pressure
A
- two solutions of different concentrations are separated by a semipermeable membrane the distribution of water across the membrane is determined by the relative solute concentration across it.
- hydrostatic pressure required to prevent movement across the membrane is known as the osmotic pressure of the solution. The greater the number of osmoles in the solution then, the greater the desire for water to move into it and therefore, the greater the hydrostatic pressure required to oppose this.
