Using a simplified ATP algorithm to improve data reliability and improve cleanliness standards for surface and medical device hygiene

Applicability of the ATP assay in monitoring the cleanliness of hospital environments

BACKGROUND

The adenosine triphosphate (ATP) assay is widely used for simple and rapid evaluation of the cleanliness of environmental surfaces. However, there remain concerns regarding the reliability of the ATP assay in hospital settings. This study aimed to assess whether the ATP assay could detect inadequate cleaning within hospital environments as well as monitor the effectiveness of routine cleaning.

METHODS

The cleanliness of seven types of high-touch surfaces in operating rooms that were routinely cleaned was evaluated by testing the ATP assay and aerobic colony counts (ACC). For pressure redistribution mattresses (Soft-nurse®) that were found to be particularly at risk of infection, cleaning methods were improved, and the effectiveness of these improvements was monitored using the same two methods.

RESULTS

The ATP assay quantitatively detected contamination on seven high-touch surfaces but showed no correlation with ACC. However, a significant positive correlation between luminescence and ACC was found on one specific surface, allowing for determining a theoretical cutoff value. Additionally, the ATP assay effectively identified the risk of future infection, which the ACC test could not assess.

CONCLUSIONS

The ATP assay can monitor the effectiveness of routine cleaning by setting a theoretical cutoff value for each subject. The method provides quantitative and meaningful values when used with an understanding of its limitations.

Adenosine triphosphate (ATP) sampling algorithm for monitoring the cleanliness of surgical instruments

BACKGROUND

Timely detection of cleaning failure is critical for quality assurance within Sterilising Service Units (SSUs). Rapid Adenosine Triphosphate (ATP) testing provides a real time and quantitative indication of cellular contaminants, when used to measure surface or device cleanliness. The aim of this study was to investigate the use of an ATP algorithm and to whether it could be used as a routine quality assurance step, to monitor surgical instruments cleanliness in SSUs prior to sterilisation.

METHODS

Cleanliness monitoring using rapid ATP testing was undertaken in the SSUs of four hospitals located in the western (Amazonia) region of Brazil. ATP testing was conducted (Clean Trace, 3M) on 163 surgical instruments, following manual cleaning. A sampling algorithm using a duplicate swab approach was applied to indicate surgical instruments as (i) very clean, (ii) clean, (iii) equivocal or (iv) fail, based around a 'clean' cut-off of 250 Relative Light Units (RLU) and a 'very clean' <100 RLU.

RESULTS

The four cleanliness categories were significantly differentiated (P≤0.001). The worst performing locations (hospitals A & C) had failure rates of 39.2% and 32.4%, respectively, and were distinctly different from hospitals B & D (P≤0.001). The best performing hospitals (B & D) had failure rates of 7.7% and 2.8%, respectively.

CONCLUSION

The ATP testing algorithm provides a simple to use method within SSUs. The measurements are in real time, quantitative and useful for risk-based quality assurance monitoring, and the tool can be used for staff training. The four-tiered approach to the grading of surgical instrument cleanliness provides a nuanced approach for continuous quality improvement within SSU than does a simple pass/fail methodology.

Development of a "Scissor-Tip-Separator" for adjustment of scissor blade separation and prevention of scissor blade damage during steam sterilization

Background

Reprocess reusable surgical instruments during steam sterilization; damage occurs to sharp scissor blades in close position, so steam cannot reach the blades. Surgical instruments' management requires standards to ensure patient safety and prevent harmful pathogens, especially in the COVID-19 pandemic. Although various devices can separate scissor blades, they do not prevent damage to cutting edges. To address the above problem, we developed a new scissor protector, the "Scissor-Tip-Separator," and evaluated its efficacy.

Methods

The "Scissor-Tip-Separator" design follows the steam sterilization guideline that instrument tips must be separated. The locking handles and V groove mechanism keep the scissor blades separated while preventing damage to the cutting edges. For efficacy assessment, purposive sampling was performed to select 44 Thai perioperative nurses at Ramathibodi Hospital, Bangkok, Thailand, to evaluate the "Scissor-Tip-Separators" in 450 sterile instrument containers. All participants evaluated surgical scissors placed in the "Scissor-Tip-Separators" during instrument setup, following a problem record checklist. At the end of the fifth use, participants were asked to complete the "Scissor-Tip-Separator" Effectiveness Scale, which was used to test the structural design of the "Scissor-Tip-Separator" in terms of function, usability, and safety. The Adenosine Triphosphate surface test was also used to validate the "Scissor-Tip-Separator" cleanliness. Data were collected from August 2020 to November 2020, then analyzed via descriptive statistics.

Results

The "Scissor-Tip-Separator" met the cleaning validation criteria, and in 44 uses, the physical property remained the same. The scissor shank was discovered loose from the handle before it had been unlocked (0.2–0.4%) at the 45^th use. Based on participants' opinions, the overall instrument effectiveness was high in terms of function, usability, and safety.

Conclusion

The "Scissor-Tip-Separator" regulates scissor blade separation under sterilization guidelines; it prevents damage to cutting edges, thus ensuring patient safety. It protects against losses in a sterile field and can prevent hand injuries.