SIMILARITIES BETWEEN HAEMODIALYSIS AND HAEMOFILTRATION.

Haemodialysis and haemofiltration are both terms which are used to describe an extracorpeal treatment which removes waste products and water from blood, using a dialyser as a filter.

DIFFERENCES BETWEEN HAEMODIALYSIS AND HAEMOFILTRATION.

Haemodialysis utilises diffusion to clear waste products and some ultrafiltration takes place (approximately 2 - 3 litres) during treatment, with minimal convection occurring . Blood is pumped through the dialyser on one side of the membrane and dialysis fluid is passed through the other side in the opposite direction, to maximise the concentration gradient.

Haemofiltration utilises the principles of ultrafiltration and convection. No dialysate fluid is required as the dialyser membrane has an increased capacity for water permeability, therefore providing a significant increase in ultrafiltration. This treatment requires replacement fluid to be provided simultaneously to the patient. It can be provided in a variety of forms and often on a continuous basis, requiring access to the venous and/or the arterial circulation of the patient.