Monitoring and Improving the Quality of Water in the Hemodialysis Machines

Background: It is important to monitor microbial contamination of water used in hemodialysis machines in order to provide safe and effective hemodialysis.  Regulatory agencies such as, the Centers for Disease Control and Prevention and the Advancement of Medical Instrumentation, have established allowable upper limits of microbial contamination of water. During routine monitoring of water in the dialysis unit, we noted bacterial counts above the allowable limits on the portable reverse osmosis machines.

Objective: In order to identify potential causes of the elevated microbial counts, a Root Cause Analysis was conducted by an interdisciplinary team consisting of representatives from Dialysis, Infection Control, Bio-medical, and Facilities Management.

Methods:  A review of water cultures for the past year revealed a consistent increase in the level of microbial counts from the portable reverse osmosis machines.  There was no increase in the number of healthcare-associated infections in hemodialysis patients during this time period.  The entire process for monitoring and maintaining the quality of water in the dialysis machines was flowcharted.  An aggressive staff education program was undertaken. In order to eliminate variance and improve accuracy, one person and an alternate were trained and assigned the task for collecting the water cultures.  The daily log for documenting results of water cultures was revised to ensure appropriate follow-up.  A database was created for tracking water cultures.  Those requiring actions were highlighted in yellow or red depending upon the microbial count.  The database also included the dates of cleaning and disinfection of the central water system and dialysis machines.  The data were reviewed by the Hospital Dialysis Unit Governing Body and the Infection Control Committee.

Results: The efforts of this interdisciplinary team resulted in significant reduction in microbial contamination of water in the Dialysis Unit.  Water cultures from the portable reverse osmosis machines that exceeded the allowable level were reduced from forty-eight percent to two percent after process changes.   

Conclusions: The process changes and ongoing feedback of information from infection control to the interdisciplinary team made positive impact on our water culture surveillance program and served as the basis for implementing a process structure that ensures adherence.