ATP – Rapid hygiene testing in healthcare

What is ATP? (Adenosine Triphosphate)

ATP is an energy-giving chemical found in all living things and is a universal indicator of organic residue.

How is it measured?

Hygiena ATP testing devices contain a natural enzyme found in fireflies. This enzyme produces a simple bioluminescence (light giving) reaction when it comes in contact with ATP.

Using Bioluminescence technology, Hygiena Luminometers can measure extremely low levels of ATP collected with testing devices (swabs). Measuring light produced from the reaction with ATP gives an excellent indication of surface cleanliness because the quantity of light generated is directly proportional to the amount of ATP present in the sample. The reaction is immediate, and results can be processed in seconds. The result is expressed numerically on the luminometer screen as a Relative Light Unit (RLU).

Establishing RLU Limits – What is a Pass or Fail?

Determining RLU pass/fail limits is a fundamental element to a successful ATP cleaning verification program. Setting RLU limits too high may allow contamination to persist on surfaces, endangering patients and staff. Setting them too low may result in overuse of cleaning supplies and excessive labour. Although there are no regulatory standards for RLU limits, peer reviewed studies and data from hospitals that have implemented the Hygiena system offer insight to help hospitals set appropriate RLU Pass/Fail limits according to industry accepted practices.

Literature review

In a recent study conducted by North Tees and Hartlepool Hospitals in the UK, data showed that by monitoring cleaning performance with the Hygiena SystemSURE Plus, these two hospitals experienced a 20% increase in Pass scores. In this study, Pass scores were categorised as any score below 100 RLU. During this time, the hospitals also experienced a 35.24% reduction in reported post 48-hour C. difficile infections. (Hygiena 2012) ⁽¹⁾

Mulvey, et al validated the Hygiena SystemSURE Plus ATP system and reported “An ATP benchmark value of 100 relative light units (RLU) offered the closest correlation with microbial growth levels <2.5 CFU/cm²”. (Mulvey, 2011) ⁽²⁾

Willis, et al compared visual inspection, microbiological analysis and ATP bioluminescence test results using Hygiena’s system. This study found that of all sites samples, 36% gave unsatisfactory (Fail) results. Using a benchmark of 100 RLU, ATP bioluminescence test results delivered 37% unsatisfactory (Fail) results. (Willis, 2007) ⁽³⁾

Gauci, et al validated the 100 RLU benchmark, showing that ATP monitoring objectively quantified a 77–92% increase in cleanliness. (Gauci, 2012) ⁽⁴⁾

Recommendations

Based on clinical experiences and current literature, Hygiena recommends Pass/Fail RLU limits according to broad risk categories listed in Table 1.

While most hospitals use recommendations in Table 1 below, it is possible to create custom limits for test locations.

Surface/Application	Pass	Caution	Fail
Public area	100	101–200	>200
Near patient areas	50	51–100	>100
High-care areas	25	26–50	>50
Sterile services	10	11–30	>30
Ambulances	50	51–100	>100

Anaeron is also working closely with Australian healthcare facilities on how ATP Testing can assist with the AS/NZ 4187 Guidelines which include recommendations on validation of cleaning lumen and non-lumen scopes.

SureTrend Software developed by Hygiena comes pre-set with reports, graphs and charts that help manage improvements, train staff and clearly illustrate performance. Test results are captured and can be immediately analysed to assist in providing feedback and improve on cleaning performance. Continuous improvement is an essential part of the Hygiena ATP cleaning verification system.

For more information and all on the latest technology of Hygiena Luminometers and ATP Rapid Hygiene testing contact Anaeron Pty Ltd, distributors of Hygiena into Australian Healthcare. Phone us on 1300 936 044 or visit www.anaeron.com.au.

References:

1. Hygiena (2012) Case Study: North Tees and Hartlepool Hospitals, United Kingdom. Two Hospitals Improve Cleaning Sores and Experience Lower Infection Rates.
2. Mulvey, et al (2011). Finding a benchmark for monitoring hospital cleanliness. Journal of Hospital Infection, 25-30.
3. Willis, et al (2007). Evaluation of ATP bioluminescence swabbing as a monitoring and training tool for effective cleaning. British Journal of Infection Control, 17-21.
4. Gauci, et al (2012) Rapid objective measurement of cleanliness delivers improvements. Welsh NHS.