A quick reference guide to haemofiltration and renal failure March ...

DIFFUSION
Diffusion is defined as the movement of solutes from an area of
high solute concentration to an area of low solute concentration
across a semipermeable membrane. Ultimately, concentration of
the solute will be equal on both sides of the membrane. Diffusion
is directly proportional to the concentration gradient,
temperature and surface area. Diffusion is inversely proportional
to the thickness of the membrane. (Bellomo, Ronco and Mehta, 1996:S6)
Low concentration
high concentration equal
concentration
The concentration gradient is maintained in filtration because we
are continually adding fresh dialysate fluid to the dialysate side.
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