Fluid balance and electrolyte distribution in human body.

Osmotic Equilibrium
Plasma Osmolarity - Measures ECF Osmolarity
• Plasma is clinically accessible
• Dominated by [Na + ] and the associated anions
• Under normal conditions, ECF osmolarity can be roughly estimated
as:
P OSM = 2 [Na + ] p
……..270-300 mOsm
{ P OSM = 2[Na + ] + 2[K + ] + [Urea] + [Glucose] }