Low- (classical) and high-efficiency haemodiafiltration

The distinction between high-efficiency haemodiafiltration (HDF), usually applied with online preparation of substitution fluid, and 'classic' low-efficiency HDF (using less than 15 litres of substitution fluid) makes sense since the magnitude of convection (expressed by substitution volume) is important for the claimed benefits of HDF Many experimental and observational data support the notion that in comparison to conventional low-flux haemodialysis, high-efficiency HDF might have many clinical advantages and might prolong life. Randomized prospective trials, such as a current Dutch trial, are overdue to prove these hypotheses. Low-efficiency HDF is as effective as high-flux haemodialysis in providing convection. Clinical comparisons between high-flux haemodialysis and HDF are sparse. The magnitude of convection is indirectly dependent on the degree of extracorporeal blood flow. With 14-gauge needles, blood flows of > 500ml/min can be safely maintained without haemodynamic or hyperkalaemic consequences. With regard to blood purification kinetics, high-efficiency HDF appears ideal for performing daily short treatments. Copyright (c) 2007 S. Karger AG, Basel.