Formulated in 1896 by the British physiologist Ernest<unk> , the<unk>  illustrates the role of hydrostatic and oncotic forces (the so-called<unk>  forces) in the movement of fluid across capillary membranes.
Capillary fluid movement may occur as a result of two processes:
diffusion
filtration<unk> 's equation only refers to fluid movement across the capillary membrane that occurs as a result of filtration. In the glomerular capillaries, there is a net fluid filtration of 125 ml/min (about 180 litres/day). In the rest of the body's capillaries, there is a total net transcapillary fluid movement of 20 ml/min (about 28.8 litres/day) as a result of filtration. This is several orders of magnitude lower than the total diffusional water flux at the capillary membrane, as that is about 80,000 litres/day.
Starling equation
Henderson-Hasselbalch equation
Freundlich equation
Winters' formula
PAH clearance
Langmuir equation
Volumetric flow rate
Resistive index