Authors: T. Ohishi*, R. Fushimi
Abstract:
The cleaning result in an automated washer disinfector (WD) can be assessed by measuring the cleanliness of the surgical instruments after washing, but visual inspection does not give a quantitative result. Moreover, the method for measuring residual protein on surgical instruments is unsuitable for onsite evaluation because it is not rapid.
Adenosine triphosphate (ATP) provides energy for cellular metabolism and is present in all living cells. Accordingly, it is an excellent marker for evaluating contamination by organisms.
In this study, we aimed to measure the ATP on soiled surgical instruments, washed at 11 medical facilities in Japan and sought to identify values that could serve as reference criteria for washing evaluation.
The results suggest that ATP measurement can be considered a valuable tool for the appropriate evaluation of WD washing in real time. ATP reference values of 100 RLU for PL and 150 RLU for NU could serve as evaluation criteria for surgical instruments.
Background:
The effectiveness of an automated washer disinfector (WD) in cleaning soiled surgical instruments can be assessed by measuring the cleanliness of the surgical instruments after washing but this cannot be performed quantitatively through direct vision. Moreover, the method for measuring residual protein on surgical instruments after washing with WD is unsuitable for onsite evaluation because it is not rapid [1, 2].
Adenosine triphosphate (ATP) provides energy for cellular metabolism and is present in all living cells. Accordingly, it is an excellent marker for evaluating contamination by organisms. Moreover, by employing ATP measurement for the objective and quantitative evaluation of washing efficiency, results can be obtained in near realtime since the measurement is completed within about 30 seconds. Visrodia et al. reported that based on these characteristics, ATP measurement is effective as a reprocessing assessment tool for medical equipment [3].
Keywords:
- surgical instruments
- cleaning
- cleaning evaluation
- ATP
Surgical instruments that are used invasively must be aseptic to prevent surgical site infections (SSIs). Appropriate surgical instrument sterilization leads to reduced SSI rates and the evaluation of sterility before instrument use presumably contributes to SSI prevention [4].
Alfa et al and Parohl et al proposed, as a washing evaluation criterion after using the gastrointestinal flexible endoscope, that if the ATP measurement on the endoscope surface after hand cleaning shows a value of 200 relative light units (RLU) or above, reprocessing should be performed [5–7]. However, no study has suggested or investigated washing evaluation reference values based on ATP measurement, as a measure of improper washing. Moreover, in ISO 15883-1, although ATP measurement was listed as a washing evaluation method for the washer disinfector (WD) in the washing of stainless steel surgical instrument etc., no clear washing efficiency evaluation criteria were specified [8].
In this study, we aimed to measure the ATP on soiled surgical instruments, washed at 11 medical facilities in Japan and sought to identify values that could serve as reference criteria for washing evaluation.
Read the entire article
Photo: iStock
