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

There is restriction of movement of the medium sized molecules,
e.g. Vitamin B12, and very little movement across of large
molecules, e.g. albumin.
Molecule Molecular Weight (daltons)
Sodium 33
Calcium 40
Urea 60
Creatinine 113
Uric acid 168
Dextrose 180
Vitamin B12 1352
Myoglobin 17 000
Albumin 68 000
Globulin 150 000
The fibres within the filter vary in size and composition, with
some materials said to be more biocompatible than others and
other said to have septic mediator absorption properties.
Another important factor with filters is their size. Filter size is
described in square meters. The larger the surface area in square
meters, the greater the area of blood contact with the fibres
and thus the potential for improved ultrafiltrate formation.
([Rodda 2003])
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