[Hemodiafiltration: choice or necessity in high-efficiency treatment?].

The risks of back-filtration that occur with the use of high hydraulic permeability membranes with haemodialytic techniques in the course of which the difference between forced and necessary ultrafiltration is compensated for by correcting transmembrane pressure in favour of the dialyser compartment. In this way a form of concealed haemodiafiltration is attained in which the replacement fluid is the dialysing solution, annulling, owing to the possible consequences of the transit of bacterial endotoxins into the circulation, all the advantages linked to the use of these membranes. It is concluded by suggesting the implementation of well controlled haemodiafiltration through the careful quali-quantitative evaluation of the replacement fluid.