Hemodiafiltration: Evolution of a technique towards better dialysis care.

Technological developments in the fields of membranes, machines and fluids have contributed to making hemodiafiltration (HDF) a safe and effective technique. Synthetic membranes with combined hydrophilic-hydrophobic structure and reduced wall thickness allowed to combine diffusion and convection into a unique technique. Accurate volumetric ultrafiltration control systems in dialysis machines reduce the risk for fluid balance errors and allow to perform safe and efficient online HDF. In fact, modern dialysis machines are equipped with specific balancing systems to manage fluid reinfusion and ultrafiltration simultaneously. Online preparation of sterile and pyrogen-free solutions for infusion is today possible, allowing the safe infusion of large fluid volumes during a HDF session. Dedicated software and enhanced user interfaces of modern dialysis machines simplify the procedures and reduce both operator workload and error. Emerging evidence suggests that these therapies may be superior to classic diffusive hemodialysis in terms of morbidity, and perhaps even mortality. There is a need for better understanding of the mechanisms involved, as well as further confirmation of these encouraging findings with prospective controlled trials. Nevertheless, HDF appears a promising therapy that likely will improve patient outcomes. Based on these considerations, HDF has the potential to become the new gold standard for dialysis in the years to come.