The specific treatment of water applied to the health sector

The need for a higher quality of water, ultrapure, used in the preparation of the fluid from dialysis (LD) mainly resulting from the use of high flow dializadores with high probabilities of retrofiltración and the so-called technical online, own LD infusion the patientset out the need for new elements and/or configurations in the treatment of water, in such a way that not only is achieved this water quality of immediately after the installation or modification of treatment but will stay over time reliablyboth in quality and in quantity, because the water will be more than 96% ld.

There are several recommendations, widespread, of what should be treatment of water to reach the quality of ultrapure water pretreated once: double stage of osmosis, or a stage with a second element consisting of one of the following options or combination thereof(: to) lamp U.V. more ultrafiltro; (b) ultrafiltro; (c) electrodesionizador. At the same time, it is necessary to design and implement elements engaged in a cleaning function to provide the delay of the deterioration of the quality and quantity of water produced by the loss of effectiveness of the different components of the treatment, mainly due to the accumulation in the membrane of osmosis of the elements it retained.

So important like the treatment of water is the distribution of the same until the monitors of hemodiálisis: the water treated stored is susceptible to suffer pollutions; they do not have to exist bottoms of sack, pieces with cracks or forms that can serve of reservorio or prevent the flow laminar, including like part of the network of distribution the own tube of taking of water of the monitor. By all this the water has to to be distributed of way this in permanent circulation, included until the monitor, to speed around >1m\1s\2returning the no used to the treatment of water and be again treated.

The service of Nephrology, along with the direction of the University Hospital of the Princess of Madrid, established the need for a new treatment of water and distribution network for the hemodialysis unit due to the seniority of the earlier, which was capable of maintaining the chemical and bacteriological levels according to established standards, but with constant insecurity of this retention over time or between controls, which made it impossible to address the use of new techniques of hemodialysis (on line) requiring a total security on the quality of the water.

Points in which it based the inhygiene:

- Configuration of the ósmosis reverse already obsolete, with bad estanqueidad between membranes that could involve during the phases of stopped the step of water through them; an alone stage of the same and without elements of disinfection and/or desincrustración of the same, by what had to realizar with external elements to the same that forced to prolonged stops.

- Storage of water treated in deposits no tight.

- Network of distribution with numerous bottoms of sack, included the tubes of feeding of water of the monitors, pipes excessively big that involved a speed < 0'3 m\1s\2and the possibility that it did not circulate to section of complete tube, realizar in PVC that is able to degrade over time and contribute undesirable elements to the water included the glues used in his setting.

- did not exist any element in the network of distribution to avoid pollutions.

- In case of failure of the ósmosis it was necessary to paralyse the sessions of hemodiálisis or dializar with water pretratada.

- When it was necessary to effect a disinfection of the network of distribution and storage only could realizar in Sunday because of the high necessary time.

In addressing the new design of the treatment of the water and start to provide solutions to the problems mentioned were new ones derived from new designs: If we stored water treated to ensure the General recommendation of 24 h. of supply capacity was supposed to enter tanks of a capacity of 󖐪. 000 litreswhich involved a large amount of space and a reform of the architectural structure which were to be placed due to the weight, adding the difficulty of introducing deposits of this capacity near the unit.

If we did the network of distribution facilities denominated in U, reaching as far as the monitor to eliminate the water inlet hose, in order to avoid the SAC funds, we were in danger of a sudden movement of a monitor could result in cuts of water to the rest of the unit, or a break in the network left without water to it. The novelty of the treatments referred to as Online, i.e. water supply direct to monitors from the treatment without storage of treated water, seemed to us that it could solve many problems in addition to seem the best guarantee of water quality steadilytogether with other aspects of the installation, but there were also other new problems that we forced them to give other solutions. We finally opted for a treatment of this type, of the company Lauer, marketed in Spain by the Palex group.

The gross water supply was certainly one of the more complicated options. To not store treated water it became necessary to ensure the constant gross water supply, as in the case of the same court was automatically stopped the production of treated water. Obviously if we had to store crude water we found ourselves with the same problems mentioned in the case of storage of treated water. The solution was to conduct a double onslaught of gross water, a totally individual for the unit, with a double group of bombs (working and reserve) who take water directly from the first well where the water supply company to the hospitalacting this onslaught as a priority; the second connection comes from the distribution network of own hospital, which takes water from a second well and serving it as a reserve. Both have their corresponding individual alarms of pressure decrease. This design has avoided the need to store water for hemodialysis. The amount of water stored by the tanks of the hospital is approximately 500 m³.

The analysis of the obtained water throughout these months of operation indicates a quality of highly purified water, with negative microbiological controls (UFC/ml) and endotoxins below 0.03 EU/ml; in microbiological cultures there is some exception that seems more derived from own manipulations during the captures of samples.

Aluminum, indicative of chemical quality, was the element that more complications we caused with the old plant and we were forced, as I have already mentioned, to work with a very high rejection percentage. Currently stays below the 5 g/l, detectable limit by the laboratory; the generalized maximum value (standards UNE, AAMI, etc.) is 10 g/l. The rest of chemical pollutants remain below the permissible ceilings internationally by the various standards, even below detectable levels. Ion rejection by osmosis (relationship between conductivity of the entrance to the osmosis and the permeated water or treated water), is > 99% for values of the conductivity of input > 100 μS, and > 98% for values of conductivity of entry < 100 μS.