Development of online hemodiafiltration in Japan

Evidence concerning online hemodiafiltration (ol-HDF) includes increased uremic toxin removal, prevention of dialysis-related hypotension, improved survival, and recovery of dialysis-related uncertain symptoms. In particular, evidence has been shown regarding prevention of dialysis hypotension and improvement of survival, but the mechanism of its manifestation is still unclear and its effects themselves are questionable. In Japan, pre dilution ol-HDF is mainly performed, and improvement in survival rate has been shown on the condition of convection volume is 40 L/session or more. In particular, the removal of alpha 1-microglubulin (alpha MG), which is a medium-middle solute, is targeted. The antioxidant action (Heme Scavenger) of alpha MG, is presumed, but in dialysis patients, the majority in serum are deteriorated (oxidized) alpha MG. It has been pointed out that removing the deteriorated alpha MG by ol-HDF may produce new alpha MG from the liver and lead to recovery of the original antioxidant effect. However, clinical evidence of this mechanism is desired. Obtaining evidence for the indicated alpha MG removal activity of ol-HDF will lead to advancement in HDF.