Online high-dose hemodiafiltration: a path towards improved clinical outcomes and green dialysis

Purpose of review There are concerns that online high-dose hemodiafiltration (HDF) is particularly resource-intensive and environmentally challenging. It has recently been suggested that HDF consumes more water and generates more plastic waste than expanded hemodialysis (HDx) using medium cut-off membranes. To further address this matter, we examined the available evidence on water use and plastic waste generation across high-flux hemodialysis, HDx, and HDF. Recent findings Our analysis reveals that plastic waste generation is lowest with HDF and highest with HDx: modern HDF dialyzers weigh on average 36% less than MCO dialyzers, and online HDF requires no saline bags, together saving approximately 68–123 kg of plastic per 1000 sessions compared to HDx. Regarding water, online high-dose HDF may use less water than HD or HDx if dialysate flow is minimized/optimized (−8% vs. hemodialysis at standard European dialysate flow; −12.6% in a US setting). Individualization of dialysate flow reduces water consumption by a further 27.8% without compromising dialysis adequacy. Summary Despite the suggestive ‘high-dose’ attribute in its name, online high-dose HDF with optimized dialysate flow may use less water and generates substantially less plastic waste than HDx. These findings challenge the view that HDF adoption is environmentally costly and indicate that HDF is a meaningful step towards green dialysis.