Hospital surfaces and infection rates
Why do infection rates peak in some hospitals and not others? Can better cleaning help?
The transmission of pathogens by human hands to adjacent areas is related to the incidence of healthcare associated infections (HAIs). Keeping environmental surfaces and equipment clean is therefore as important as hand hygiene to reduce infection and complication risk. But what products and processes are best placed to achieve effective cleaning and disinfection?
Koganti (2016) found that a virus placed on hospital floors was subsequently found on high-touch surfaces in patient rooms and nursing stations. Wei (2016) explained that people kick up pathogens on the floor as they walk. The person’s thermal plumes draw fine pathogens upward. The wake generated as the person walks can then carry a contaminated cloud to a patient’s bedside. As they stop walking, the cloud continues forward for about 15 cm and deposits pathogens onto the bed.
Cohen (2012) suggested that up to 82 people entered a typical patient room per day. Huslage (2010) found that bedrails were the most commonly touched surface, averaging three touches per interaction. This means the typical patient bedrail may be touched up to 256 times per day. Microorganisms can then spread throughout a healthcare environment and between patients within a few hours, increasing the risk of infection for patients.
Dancer (BMC, 2009) argues that hand hygiene compliance is suboptimal, especially when staff are busy. It follows that better cleaning at the point of care may help. Donskey (2013) contends that the daily disinfection of high-touch surfaces and portable equipment may be the most effective form of mitigating risk related to environmental contamination.
The Australian Guideline for the Prevention and Control of Infection in Healthcare (NHMRC, 2010) defines disinfection as a process that inactivates non-sporing infectious agents by using either thermal or chemical means. Items need to be cleaned before being disinfected. Some products do both in one step. Accelerated hydrogen peroxide, quaternary ammonium and sodium hypochlorite are the chemical disinfectants commonly used in healthcare.
Rutala and Weber (2014) suggest that the ideal disinfectant for a facility should be the one with the highest score for kill claims, contact times, safety, ease of use, and cost (including the cost of infections that may be prevented). Those factors change according to surface type, climate and demographic. There is no silver bullet or universally perfect disinfectant. Different products will be appropriate for different facilities.
Sodium hypochlorite is the liquid form of chlorine bleach and sodium isocyanurate is the dry (powder or tablet) form. Alfa (2010) notes that there are health and safety concerns related to the use of chlorine bleach and that it requires rinsing off with water as a second step.
Quaternary ammonium (quat) compounds have a retentive tendency and over-use may result in a buildup of residue. The most common quats are benzalkonium chloride and didecyl dimethyl ammonium chloride. Periodic deep cleaning with a detergent usually helps to prevent any tackiness.
Accelerated hydrogen peroxide (AHP) is a disinfectant that breaks down into oxygen and water and thus has no retentive chemistry. Boyce (2017) directly compared AHP with quat in a major teaching hospital in the first ever prospective cluster-controlled crossover trial of disinfectants. Boyce showed that the proportion of surfaces yielding no bacterial growth after cleaning was significantly greater with AHP than with quat.
After the most appropriate product for the facility or area has been chosen, then consideration should be given to an appropriate process. Microfibre is well known for its dual ability to clean and reduce bacterial surface load. However, if the disinfectant is not compatible with microfibre, then disinfection may be suboptimal. Pre-wetted disposable disinfectant wipes may be helpful, especially for surfaces at the point of care. Wipes enhance cleaning compliance, allow faster disinfection and offer time-related cost savings (Weimken, 2014).
There are many reasons for different infection and complication rates in hospitals. Better cleaning can help, but just what constitutes better cleaning? All registered disinfectants in Australia are fit for purpose, but the perfect product and process for one hospital may be imperfect for another. We can better manage HAI rates by enhancing staff hand hygiene compliance, by introducing patient hand hygiene protocols and by routinely disinfecting high-touch surfaces at the point of care with an appropriate product and process.
- Koganti S, Donskey C et. al., Hospital Floors and Pathogen Dissemination. ICHE 2016; 37 (11): 1374-1377.
- Wei J and Yuguo L., Airborne Spread of Infectious Agents Indoors. AJIC 2016; 44: 102-108
- Cohen B et. al., Frequency of patient contact with health care personnel and visitors. Jt Comm J Qual Patient Safety, 2012; 38 (12): 560-565.
- Huslage K, Rutala WA, Sickbert E, Weber DJ, Defining high touch surfaces in hospitals. ICHE 2010; 31 (8): 850-853.
- Dancer S et. al., Enhanced Cleaning in Hospitals. BMC Medicine 2009; 7:28
- Donskey (2013) Does Improving Cleaning Reduce HAIs? 2013; 41: 12-19
- Rutala W and Weber D., Selecting The Ideal Disinfectant. ICHE 2014; 35 (7): 855-865
- Alfa M et. al., Improved Eradication of C. difficile Spores using AHP. BMC Infectious Diseases, 2010; 10:268
- Weimken T et. al., The Value of Disinfectant Wipes. AJIC 2014; 42: 329-330
- NHMRC, Australian Guideline for the Prevention and Control of Infection in Healthcare. 2010
- Boyce JM et. al., Comparison of AHP and Quat on Contamination and Outcomes. AJIC 2017; 45: 1006-1010.
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