Dialysis Water, Have We Done Enough to Protect Our Patients?

21 October 2005
Sydney South West Area Health Service

This project was entered in the Baxter 2005 NSW Health Awards, Safety category.

Entries from the Baxter 2005 NSW Health Awards - full list

Authors

Dr Josephine Chow, Senior Nurse Manager, Department of Renal Medicine, Liverpool Hospital,SSWAHS
Dr Michael Suranyi, Liverpool Hospital, Department of Renal Medicine, SSWAHS
Bien Roman, Liverpool Hospital, Department of Renal Medicine, SSWAHS
Milad Francis, Liverpool Hospital, Department of Renal Medicine, SSWAHS
Deborah Knagge, Liverpool Hospital, Department of Renal Medicine, SSWAHS
Christopher Gibb, Liverpool Hospital, Department of Renal Medicine, SSWAHS

For more information on this project contact Richard Gilfillan

Abstract

Water quality testing is an essential component of haemodialysis water pre-treatment, to ensure Chloramine removal and patient safety¹. A program of water pre-treatment and testing, as well as supporting policy and procedure documentation has been developed in the Liverpool Renal Unit. In this context new technology, On-Line Chloramine Monitors, to monitor chloramine levels, was introduced to increase patient safety. The aim of this project was to establish appropriate testing procedures, calibration standards and practices, maintenance protocols and Nursing policies to ensure safe and effective use of the water quality monitoring equipment. Implementation of new practices has lead to the improved monitoring of water quality and enhanced patient safety on dialysis. This project has provided the basis for development of applicable NSW or Australian Standards for dialysis water testing, and the widespread circulation of such standards for Chlorine/Chloramine testing in NSW or Australian dialysis units will benefit dialysis practice, nursing staff and patients.

Aim

To determine the reliability and maintenance requirements for this monitoring equipment and develop applicable Australian standards for calibration, testing and maintenance of On Line Chlorine Monitors in the dialysis room.

Background

Water quality is a central and important issue in haemodialysis units. Few units however develop expertise in the area of dialysis water quality, or focus on it adequately, in terms of quality improvement. There is a fundamental lack of Australian standards or common practice, despite a NSW Health Department Memorandum in 2002³ concluding guidelines be developed for chlorine and chloramine testing of water for dialysis purposes.

Numerous reports have indicated an ongoing risk of patient injury and death associated with improperly treated water being used for haemodialysis. These reports include haemolysis due to inadequate chloramine removal. This lead to the introduction of new technology to monitor water quality in the dialysis room, to improve patient safety. On-Line Chlorine Monitors were introduced in each dialysis room, however because this was new technology appropriate policies, practices and procedures needed to be developed to govern the effective use of the equipment to improve patient safety.

Methodology

In the Liverpool Renal Unit a local multidisciplinary interest group was formed that led to the development of relevant standards, practices and procedures in dialysis water quality. The Dialysis Water Pre-treatment plant was reconfigured to improve the safety margin of chlorine/chloramine removal, to ensure that any chlorine spikes do not penetrate to patients on dialysis. Testing procedures were developed to maximise patient safety on dialysis, to ensure that residual chloramine levels remain below the safety level. Policies, practices and internal standards have been evolved, including written nursing policies and a program of dialysis nurse accreditation.
A literature review was conducted to review current Worlds Best Practice in chlorine/chloramine testing. Wide consultation was undertaken with experts on Water Pre-treatment for Dialysis Units and practices of other large dialysis units were informally assessed by telephone polling.

A need to develop local standards and protocols on water testing for chlorine/chloramine were identified as there are no standards or guidelines in Australia in water testing, other than the AAMI recommendations. The group concluded that On-Line Chlorine Monitoring, then a relatively new technology, offered the best intervention to bridge the gap between best testing/monitoring practice and existing clinical practice in our renal dialysis unit.

Planning and implementation

Following extensive consultation, our dialysis units installed On-line Chlorine Monitors, in series between the two carbon tanks, currently being recommended by the AAMI. The On-Line monitors to measure chlorine in dialysis water were sourced from a major provider of such equipment (ProMinent) (Diagram 1). Lack of Australian experience in their use in haemodialysis units meant that testing was necessary to identify the reliability, appropriate settings, calibration frequencies, probe type and schedule of maintenance and replacement. A plan of testing was evolved in conjunction with expert advice from Sydney Water, AAMI and Department of Health.

To measure the drift of sensor readings the On Line Chlorine meters were initially calibrated using a sophisticated, laboratory based methodology on site using an amperometric titrator to measure Chlorine/Chloramine very accurately in the dialysis water, with the testing being performed by a scientist from the On-Line Chlorine meter company (ProMinent), initially weekly. Testing identified that drift was not more than 5% from initial settings over a period of 6-8 weeks (Table 1). The conclusion from this was that the appropriate calibration frequency was every 2 months. The information gathered was then used to set calibration, preventive maintenance and servicing frequency policies of the On-line Chlorine Monitors.

Testing also concluded that the pre-existing manual testing methodology (DPD/Colorimetric methods) ((Graph 1) was not sensitive enough for the purpose of calibration of the On-Line Chlorine Monitor, but remained of significant use to confirm an On-Line Chlorine Monitor alarm, and to detect gross chlorine contamination of a level likely to be a risk to patient safety.

Outcomes and evaluation

The outcomes of the project:

• A comprehensive package of policies, practices and procedures for Worlds Best Practice in Dialysis water monitoring has been developed by a multidisciplinary water interest group,
• Documentation of Worlds Best Practice in On-Line Chlorine Monitoring for Dialysis Water, including record keeping, calibration frequency and methodology, testing, maintenance and Nursing Staff accreditation,
• Improved patient safety has resulted from the implementation of protocols which mandate very close monitoring of dialysis water chloramine concentrations using On-Line Chlorine Monitoring.
• A cost analysis was conducted, costing $6,942 for the first year to install the On-line Chlorine meter and the accessaries and second monthly calibration. This was the similar cost for the manual methods excluding the staffs time.

Future scope

This project has resulted in standards, protocols, practices and policies which can provide the basis for NSW or Australian standards in dialysis water monitoring. Such uniform and accepted policies need to be implemented and documented in every dialysis unit, and as a quality improvement tool to ensure ongoing efforts to achieve maximum water purity, demonstrating and achieving the highest possible level of patient safety. The simplicity of the presented design and associated requirements ensures accessibility to all dialysis units within the NSW health system. The application of the results of this project could allow the development and creation of benchmark criteria and clinical indicators for safe water monitoring in this setting.

References

1. Coutts, D. Cresta, P. & Tam, T. (2002), Carbon cylinder trail for the haemodialysis process for the Sydney Dialysis Centre.

2. Reilly, J. (2000), Dialysis treatment options: haemodialysis or peritoneal dialysis? Australian Kidney Foundation, Kidney Care News, vol.1, no. 3, pp.201-205.

3. Picone, D. (2002), NSW Health Department Memorandum Sentinel event involving dialysis patients.

4. Association for the Advancement of Medical Instrumentation (AAMI). (2004), Standard on CD- Dialysis Edition, Arlington.