[Monitoring on-line treated water and dialysate quality]

On line-treated water has been designed to obtain ultrapure water. This quality of water is obviously necessary to obtain ultrapure dialysate, although this is not the only condition. To keep the quality of the process, is necessary the continuous monitoring of the water treatment, dialysate and haemodialysis machines.

After the installation of a water treatment with these characteristics, we developed a protocol to follow up its quality. The measures included in the protocol were: a) Microbiologic, endotoxin and chemical controls of the water on different stage: before and at the end of the treatment, pre-treatment and network of distribution. The chemical analysis included analytical and colorimetric measures. b) Control of specific mechanical functions of the facilities. c) Microbiologic and endotoxin analysis of the dialysate produced by haemodialysis machines. d) Control and maintenance of haemodialysis machines, according to the technical indications.

We analyse the initial five years of water treatment with the aim to evaluate quality parameters and efficiency. We explain the reasons of the modifications introduced in the system. During this period we have not any episodes of global or partial contamination. We refer here some incidents related with the quality of raw water supply before the treatment, but in any case it was necessary neither to stop the water supply or to reduce the water quality. We observed a persistent contamination of one haemodialysis monitor due to the port used to get the samples.

On line-treated water is at present the most appropriate system to obtain high quality water for haemodialysis. The process must be continuously monitored through specific protocols developed to evaluate the raw water's characteristics and the treated water.