Dialysis Water Distribution System and Materials
Once water enters a hemodialysis center, the goal is to achieve high quality and safe hemodialysis water and dialysate. Water treatment, system design, and distribution material choices are contributing factors. Dialysis water treatment should remove chemical and microbial contaminants to below established allowable limits and is characterized by two phases:
(i) RO System, which is the process of physically removing and/or chemically inactivating remaining chemical and/or microbial contaminants.
(ii) Pretreatment, where constituents are removed from the feed water to protect the downstream treatment components.
The AAMI 2011 recommendations include a material compatibility, commonly used three (3) materials in the distribution system and available disinfectants. The materials were cross-linked polyethylene (PEX), stainless steel (SS) and acrylonitrile butadiene styrene (ABS). The disinfectants included were sodium hypochlorite (chlorine bleach), peracetic acid, hot water, and ozone (dissolved in water). Peracetic acid was listed as compatible with all distribution materials. Incompatibilities between distribution materials and disinfectants were sodium hypochlorite with SS and ABS; hot water with ABS and ozone with ABS. The incompatibilities could cause leaching or corrosion of the materials, which may pose a risk to the patients or integrity of the system.