FLUID DISTRIBUTIONS

what are the two different types of water loss from the skin

Sweat

• variable (and can be somewhat prevented) and from sweat glands includes solute loss

Insensible fluid

from skin (and respiratory tract)

• no solute loss

cannot be prevented

evaporation of insensible fluid is a major source of heatloss per day but is not under regulatory control and cannot be prevented

how is K+ lost???

predominantly via urine little is lost in sweat or faeces in normal conditions

control of this loss is at the kidney K+ is freely filtered

reabsorbed in the PCT

controlled secretion in the DCT