Material compatibility and communication remains crucial in the fight to prevent healthcare associated infections

The surface environment presents an important route of transmission for microorganisms; when cleaning is suboptimal, it can place patients, staff and visitors at risk¹. Use of disinfectant wet wipes for surface decontamination is the industry standard for infection prevention and control professionals worldwide.

Evidence shows that this decontamination process, available at the point of care, is more streamlined and potentially increases compliance^2-5. The use of pre-impregnated, combination detergent/disinfectant wet wipes has advantages over the use of solutions and sprays. Dry wipes can interfere with the action of common hospital disinfectants, chlorine solutions can be inactivated by organic matter and daily mixing of solutions is associated with user error^6-7. Wet wipes deliver a consistent, stable dose of biocides that can be tested in situations that reflect healthcare practices. It is for this reason that the use of wet wipes within healthcare settings is more common than ever before. For the removal or reduction of microorganisms, three categories of wipes exist: detergent wipes, disinfectant-only wipes and combination disinfectant/detergent wipes. Evidence shows that combination detergent/disinfectant wipes are more effective at reducing bacterial burden than detergent-only products, which have also been demonstrated to transfer organisms to multiple surfaces⁸. Cleaning compliance, efficiency of cleaning and cost savings in terms of staff time are increased with use of ready-to-use disinfectant wipes⁹.

However, despite the wealth of evidence on the use of wipes as part of an IPC strategy, material compatibility between wipes and their surface environment remains a concern within Australia. The Victoria Managed Insurance Authority (VMIA) continue to receive reports of cracking and breakages in a number of medical devices, electrical outlets and plastic fittings used in the hospital environment. In addition, the Australian Therapeutic Goods Administration (TGA) have issued medical device safety updates highlighting that certain disinfectant wipes and detergents can damage medical devices if the cleaning agent is incompatible with the device’s plastic surfaces^10,11.

This situation is not unique to Australia, in the United Kingdom the Medicines and Healthcare Regulatory Authority (MHRA) issued an alert highlighting damage to tympanic thermometers, patient monitors, infusion pumps and other equipment. They stated that both detergent and disinfectant wipes can cause damage if incompatible with polycarbonates and blends (thermoplastics) used for device enclosures or components of many healthcare items¹². Other electronic items such as diagnostic devices may be repeatedly exposed to cleaning agents and disinfectants to render them safe for the next user. While these materials are generally tough, some chemical interactions may contribute to brittle fractures at relatively low stress levels. Cracked polymer housings, also known as environmental stress cracking, may occur after only three to four months of use in healthcare environments¹³. Damaged surfaces compromise the ability to decontaminate adequately and may affect functionality. The UK Medicines and Healthcare Regulatory Authority (MHRA) has taken a stance that failure to follow a manufacturer’s decontamination instructions should be considered ‘off-label’ use and that only products sanctioned by manufacturers and supplied by employers should be used¹⁴.

The TGA first issued a Medical Devices Safety Update in May 2017 which raised huge concerns and confusion regarding the use of widely used disinfectant wipes containing Quaternary Ammonium Compound (QAC) based disinfectants on plastic surfaces within the healthcare environment¹¹. However, QACs are a popular choice for healthcare disinfectants because of their ability to also act as detergents; this allows manufacturers to formulate products that clean and disinfect in one step — vital for improving staff compliance and ensuring infection prevention and control policies are carried out. This update also highlighted that healthcare staff were not following the instructions for use by the manufacturer. Similar issues regarding compatibility and practice were also reported in the UK in 2013 by the Medicines and Healthcare Regulatory Authority (MHRA)¹⁵. Following further investigations, the TGA have subsequently re-issued their update with several clarifications:

1. Certain disinfectant wipes and detergents can damage medical devices if the cleaning agent is incompatible with the device’s plastic surface^[1].
2. Detergent wipes used by the hospital to clean the pumps contained the ingredient ‘benzalkonium chloride’. This is classed as a quaternary ammonium compound which is a corrosive ingredient and therefore should not be used^[2].
3. Health facilities should review all decontamination processes that use a disinfectant wipe or detergent containing quaternary ammonium compounds on a plastic surface^[3].

These clarifications should provide reassurance to those using disinfectant wipes with QACs. They also follow the guidance of the UK model that both manufacturers of wipes and healthcare equipment need to work collaboratively to ensure material compatibility.

Selection of equipment constructed from polymers tolerant of agents required for effective decontamination and selection of wipes with greatest compatibility, backed up by compatibility data, are of equal and high importance. Infection prevention efforts and patient safety may be compromised if both are not considered in conjunction. Ultimately, both manufacturers of wipes and healthcare equipment should have a shared vision to protect patients. When buying equipment that will need to be decontaminated between uses, the mantra should continue to be “if you can’t clean it, don’t buy it”.

^[1] The TGA considers cleaning agents that contain levels of benzalkonium chloride below 5–10% are safe to use on medical devices. Disinfectants generally use about 0.5% benzalkonium chloride, which is considered noncorrosive at these levels.

^[2] Benzalkonium chloride is unsafe at a concentration above 10% and therefore should not be used without being diluted.

^[3] Particularly if the surface is made of polycarbonate material.

References

1. Health Protection Scotland, Standard Infection Control Precautions Literature Review: Management of care equipment. 2016, Health Protection Scotland: Glasgow
2. Rutala, W.A., Weber, D.J., Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008.
3. Rutala, W.A., Weber, D.J., Disinfectants used for environmental disinfection and new room decontamination technology. Am J Infect Control, 2013; 41(5): S36-41.
4. Rutala, W.A., Weber, D.J., Disinfection and sterilization: an overview. Am J Infect Control, 2013; 41(5):S2-5.
5. Berendt, A.E., Turbull, L., et al. Three swipes and you’re out: How many swipes are needed to decontaminate plastic with disposable wipes? Am J Infect Control, 2011; 39(5): 442-3.
6. Bloss, R., Meyer, S., et al. Adsorption of active ingredients of surface disinfectants depends on the type of fabric used for surface treatment. Journal of Hospital Infection, 2010; 75(1): 56-61.
7. Humphreys, P.N., Finan, P., et al. A systematic evaluation of a peracetic acid based high performance disinfectant. Journal of Infection Prevention, 2013; 14(4): 126-131.
8. Sattar, S.A., Bradley, C., et al. Disinfectant wipes are appropriate to control microbial bioburden from surfaces: use of a new ASTM standard test protocol to demonstrate efficacy. Journal of Hospital Infection, 2015; 91(4):319-25.
9. Wimeken, T.L., Curran, D.R., et al. The value of ready-to-use disinfectant wipes: compliance, employee time, and costs. Am J Infect Control, 2014; 42(3): 329-30.
10. Disinfectant wipes and detergent used on reusable medical devices with plastic surfaces. Risk Alert. Victorian Managed Insurance Authority, Melbourne 2017. [Available from http://www.vmia.vic.gov.au/risk/risk-alerts/risk-alert1]
11. Medical Devices Safety Update, 5(3), Therapeutic Goods Administration, May 2017. [Available from http://www.tga.gov.au/publication-issue/medical-devices-safety-update-volume-5-number-3-may-2017#a2]
12. Ayliffe, G.A. Sterilization, disinfection and cleaning of medical equipment: Guidance on decontamination from the Microbiology Advisory Committee to the Department of Health Medical Devices Dictorate, MHRA, Editor. 2010.
13. Hoffman, J.M., Sjong, A. ESC of polycarbonate exposed to hospital disinfectants. Society of Plastic Engineers, 2013.
14. Medicines and Healthcare products Regulatory Agency. Medical devices in general and non-medical products. MDA/2010/001, MHRA, Editor. 2010: London.
15. Medicines and Healthcare products Regulatory Agency. Ensure detergent and disinfectant wipes are compatible with the device. MDA/2013/019, Editor. 2010: London.