Staphylococcus aureus is a major cause of healthcare-associated infections (HCAIs) and, despite the decline of meticillin-resistant Staph. aureus (MRSA), infection remains a major cause of avoidable morbidity and mortality in hospitals (Bradley et al, 2017). Patients in intensive care units (ICUs) are at particular risk from the complications of HCAI and have a worse clinical outcome as a result of these than patients on general wards (Nuvials et al, 2015). The ICU is also a potential reservoir that can lead to the spread of hospital infections (Edgeworth, 2011; Bradley et al, 2017) and research suggests that infection control procedures undertaken in ICU affect patients throughout the entire hospital (Bradley et al, 2017).
For many years, a key approach to infection prevention was to identify MRSA-colonised patients, isolate them and instigate a targeted decontamination regimen using topical antimicrobials. There is, however, evidence that universal rather than targeted decontamination in ICU is more effective at reducing rates of bloodstream infections and in lowering costs (Robotham et al, 2011; Huang et al, 2014).
One concern about this strategy is the reliance on chlorhexidine for body washing because of increasing reports of microbial resistance (Spencer et al, 2013). This has led to interest in octenidine as an alternative agent (Spencer et al, 2013) and, in particular, the use of octenidine-containing single-use wash mitts, which may offer significant advantages in ICUs as part of an overall infection control strategy.
Healthcare-associated infections
HCAIs are infections occurring in a healthcare setting that were not present before the patient was admitted, and they remain one of the most common types of adverse events affecting patients (Haque et al, 2018), with the potential to exacerbate illnesses, delay recovery and reduce quality of life (National Institute for Health and Care Excellence (NICE), 2017).
It is estimated that 5–15% of hospitalised patients acquire an HCAI (Haque et al, 2018). The most recent NICE (2014) data indicate a hospital prevalence in England of 6.4%, however these data are almost 10 years old. More recent modelling figures show that there could have been 834 000 HCAIs, potentially costing £2.7 billion and leading to an additional 7.1 million occupied hospital bed days in 2016–2017 in England (Guest et al, 2020).
An estimate for the total annual cost of HCAIs to NHS England for 2020 has been put at between £1.6 billion and £5 billion (Cawthorne et al, 2020). To put this in context, the total NHS England commissioning budget for 2019–2020 was £121 billion, meaning that HCAIs account for roughly 1.3-4.1% of the total budget (Cawthorne et al, 2020).
There is a robust body of evidence describing interventions that can substantially reduce the incidence of HCAIs, with analyses indicating that at least 50% are preventable (Zimlichman et al, 2013).
Staphylococcus aureus and HCAIs
HCAIs are caused by a wide range of microorganisms, including MRSA, meticillin-sensitive Staph. aureus (MSSA), Clostridium difficile and Escherichia coli (NICE, 2014). Some of these may be carried by patients themselves, and 25–30% of the UK population will be positive for skin or nasal carriage of Staphylococcus (Jeans et al, 2018). This type of colonisation is a proven risk factor for subsequently developing infection during a hospital stay (Jeans et al, 2018).
Staph. aureus (both meticillin-resistant and meticillin-susceptible strains) accounts for more HCAIs than any other pathogen. Up to 33% of patients newly identified as MRSA positive go on to develop an infection, regardless of whether the initial MRSA-positive culture represented colonisation or infection (Huang et al, 2013).
Despite the decrease in MRSA bacteraemia since mandatory surveillance began in April 2007, there was a rise in bacteraemia between January and March 2021, the highest rates seen for hospital-onset MRSA bacteraemia since 2011 (UK Health Security Agency (UKHSA), 2022). Likewise, rates of MSSA bacteraemia continue to rise, peaking in 2021 at 13.4 cases per 100 000 bed-days and 998 cases—the highest MSSA hospital-onset rate and count since MSSA surveillance began (UKHSA, 2022). These rates of MRSA and MSSA confirm that vigilance and preventive measures continue to be paramount.
Intensive and ward care: definitions
The Intensive Care Society (2021) defines four levels of hospital-based patient care. In this article, the term ICU refers to patients receiving Level 2 and Level 3 critical care.
- Level 1 enhanced care: patients require detailed observations or interventions, including basic support for a single organ system, and those stepping down from higher levels of care
- Level 2 critical care: patients require higher levels of observations or interventions than level 1, including basic support for two or more organ systems and those stepping down’ from higher levels of care.
- Level 3 critical care: patients need advanced respiratory monitoring or monitoring and support for two or more organ systems at an advanced level
Infections in ICU
Invasive procedures are frequently required in ICUs, raising the risk of HCAI (Nuvials et al, 2015), which have a significant negative impact on clinical outcomes. ICU patients are at greater risk from complications of such infections: they have higher mortality rates, longer stays in hospital and are more severely ill than those without an HCAI (Nuvials, 2015).
Between 9% and 37% of patients admitted to ICU have an HCAI (Haque et al, 2018) and a study examining all infections in ICUs in a Spanish registry found that 26.4% of infections were HCAIs (Nuvials et al, 2015).
ICU patients also have higher rates of MRSA colonisation and transmission than those on non-critical care wards, with a prevalence on admission to ICU of 11.3% compared with 6.7% on other hospital wards (Edgeworth, 2011). The MRSA acquisition rate on an ICU is almost twice as high as it is outside the critical care setting (Edgeworth, 2011). Once discharged from an ICU, patients colonised with MRSA will spend significantly longer in hospital than MRSA-colonised patients admitted to general wards without previous treatment in ICU (Edgeworth, 2011).
Case for decontamination in ICU
Decontamination is used to help reduce HCAIs and, particularly, Staph. aureus transmission; it usually includes a multi-day regimen of body washing with an appropriate skin cleanser (Huang et al, 2013). Both targeted and universal decontamination of patients in ICU are potential strategies to help prevent HCAIs (Huang et al, 2013):
- Targeted decontamination involves screening, isolation and decontamination of MRSA carriers
- In universal decontamination, patients are not screened and all undergo a decontamination regimen (Huang et al, 2013).
A trial examining the impact of both strategies in ICU concluded that universal decontamination was more effective, as it significantly reduced MRSA-positive clinical cultures by 37% and bloodstream infections from any pathogen by 44% (Huang et al, 2013).
A study undertaken by Robotham et al (2011) concluded that all decontamination strategies in ICU improved health outcomes, as well as cutting the costs of healthcare provision, although universal decontamination (regardless of MRSA status) was the most cost-effective.
Similar findings were reported in Huang et al's (2014) US study. Universal decontamination provided both lower intervention costs and lower total ICU costs than screening and isolation or targeted decontamination.
Colonised and infected patients in ICU act as reservoirs for the spread of MRSA. This is supported by a study at University Hospitals Birmingham (UHB) NHS Foundation Trust. UHB is a tertiary referral teaching hospital in Birmingham in the UK that provides clinical services to nearly one million patients every year. The researchers found that universal decontamination in the ICU had a positive effect across the entire hospital (Bradley et al, 2017). In 2014, routine MRSA decontamination in ICU was discontinued, which led to a 250% increase in bacteraemia cases across UHB (Bradley et al, 2017).
As a result, in December 2015, routine decontamination in ICU (using daily octenidine dihydrochloride solution) was reinstated. Six months later, cases showed a significant decrease in MRSA, falling from 2.8 to 0.9 per 100 000 bed days. The researchers concluded that routine decontamination for MRSA in a large ICU setting is an effective strategy to reduce the spread and incidence of MRSA across the whole hospital (Bradley et al, 2017).
Selecting an antimicrobial body wash
Chlorhexidine is the main active agent used for decontamination and indications for routine use in ICU are increasing. However, there are concerns about increasing microbial resistance to solution (Spencer, 2013); chlorhexidine resistance genes have been reported in around 5-10% of UK MRSA strains (Edgeworth, 2011). Several side effects have been reported relating to the use of chlorhexidine, including contact dermatitis and anaphylactic reactions (Lachapelle, 2014).
Another available agent for topical decontamination use is octenidine, a broad-spectrum antimicrobial that is less susceptible to bacterial resistance (Hübner et al, 2010) and has the potential to lower HCAIs in ICU (Spencer et al, 2013).
Octenidine
Octenidine dihydrochloride is a topical antiseptic that has been used for more than 30 years in a range of preparations for antisepsis at sites including skin, wounds and the oral cavity. It binds to negatively charged microbial cell envelopes and disrupts microcellular metabolism. In vitro, it has been shown to be more potent than chlorhexidine against pathogens including Staph. aureus, E. coli, Klebsiella pneumoniae, Proteus mirabilis and Pseudomonas aeruginosa (Spencer et al, 2013).
With activity against Gram-positive and Gram-negative bacteria (Al-Doori et al, 2007), octenidine is a broad-spectrum antimicrobial. It has not shown any loss in antimicrobial efficacy against multi-resistant bacteria (Hübner et al, 2010), has good skin compatibility (Vanscheidt et al, 2012) and no side effects have been described when it is used as a topical antiseptic (Lachapelle, 2014). Octenidine also has a residual antimicrobial effect on the skin, which lasts for at least 48 hours and may contribute towards a decreased risk of infection (Lutz et al, 2016).
Additionally, there are reports of patient preference for octenidine, with UHB switching from chlorhexidine 4% body wash to octenidine dihydrochloride solution, when decontamination was reintroduced in 2015 (Bradley et al, 2017). The reason(s) for octenidine dihydrochloride solution being preferred by patients were not, however, indicated in the study report.
Octenidine in ICUs
There is considerable evidence supporting the use of octenidine for decontamination in ICUs because of its potential impact on reducing the number of HCAIs (Spencer et al, 2013; Gastmeier et al, 2016; Messler et al, 2019). A study of 12 855 patients on medical ICUs, where the MRSA screening and isolation policy was replaced with universal decontamination with octenidine nasal gel and octenidine wash cloths, reported a significant reduction in ICU-acquired bloodstream infections and ICU-acquired MRSA (Gastmeier et al, 2016).
In a 12-month study on a 24-bed ICU, daily bathing with octenidine was routinely used on a 5-day cycle for all patients, regardless of whether they were colonised with MRSA. Acquisitions of MRSA decreased from 25 to 6 following the switch to octenidine and the mean number of monthly cases was 76% lower than before the octenidine daily bathing intervention (Spencer et al, 2013).
Universal octenidine-based bathing was introduced to help reduce the rising incidence of vancomycin-resistant Enterococcus faecium in ICUs in Germany. Other nosocomial cases of infection were also increasing in the ICU. In the first 7 months after the intervention was brought in, the mean rate of nosocomial cases fell from 7.55/1000 to 2.61/1000 patient-days. Nosocomial infections were significantly reduced from 13 cases to one case (Messler et al, 2019).
Research
With a growing body of evidence supporting the use of octenidine in ICU, the first multicentre, cluster-randomised, placebo-controlled, cross-over trial evaluating antiseptic body wash with octenidine is being undertaken. Researchers are testing the hypothesis that daily antiseptic body washing with octenidine reduces the risk of ICU-acquired primary bacteraemia and ICU-acquired multidrug-resistant organisms. The experimental intervention consists of using octenidine-impregnated wash mitts for the daily routine washing procedure for ICU patients. This will be compared with using placebo wash mitts. The EFFECT study aims to recruit 45 ICUs with approximately 225 000 patient-days per year (Meißner et al, 2017). The results are expected later in 2022.
This current research comparing placebo mitts and octenidine mitts will be significant in illuminating whether it is the octenidine agent that is having an impact on multidrug-resistant organisms.
Further research is needed to establish whether it is the practice of using wash mitts (octenidine or placebo) or more generally providing training, raising staff awareness regarding decontamination and carrying out routine cleansing that have a greater impact.
Octenidine-containing wash mitts
In addition to evidence supporting the use of octenidine as a body wash in ICU, there is interest in the possibilities offered by octenidine-containing wash mitts. The mitts have been positively evaluated in several studies in ICUs, including one that demonstrated a significant reduction in ICU-acquired bloodstream infection and ICU-acquired MRSA (Gastmeier et al, 2016).
The ICU at Royal Berkshire NHS Foundation Trust started using Octenisan wash mitts in 2014 for routine skin cleansing of all ICU patients. The mitts replaced washing with a disposable bowl, soap and towels and became an element of agreed best practice on the unit. Their use is now mandatory for daily patient cleansing and every patient admitted to ICU is prescribed Octenisan wash mitts. In a qualitative evaluation, it was reported that the mitts make it easier to clean patients thoroughly, even in difficult-to-reach areas (Savage and Crisford, 2022). Staff were highly positive about them, commenting on their ‘ready-to-use convenience’ and ‘time-saving’ qualities. Unlike washing solutions, which require a leave-on period and then rinsing, the mitts do not need to be rinsed and the skin dries quickly (Savage and Crisford, 2022).
It is worth acknowledging that introducing a new intervention can itself increase vigilance and compliance with interventions and routine care. This may be contributing to the positive effects seen.
Benefits of waterless patient washing
The use of wash mitts also helps facilitate a move towards waterless patient washing in healthcare settings including ICUs, helping to reduce HCAIs (Hopman et al, 2017).
Sinks in patient rooms are associated with HCAIs. A 2-year study evaluated the effect of removing sinks from ICU patient rooms and introducing water-free patient care, on Gram-negative bacilli colonisation rates (Hopman et al, 2017). This intervention was followed by a statistically significant immediate reduction in Gram-negative bacilli colonisation. The reduction rate was more pronounced in patients with longer stays in ICU, from a 1.22-fold reduction (≥2 days) to a 3.6-fold reduction (≥14 days; P<0.001)(Hopman et al, 2017). Researchers concluded that removing sinks from patient rooms and introducing water-free care were associated with a significant reduction in patient colonisation with Gram-negative bacilli, especially in those with a longer ICU length of stay (Hopman et al, 2017).
Further research shows both staff and patients are generally positive about washing without water (Schoonhoven et al, 2015), with 61% preferring to wash without water to standard bed baths and it was viewed as a more efficient alternative (Schoonhoven et al, 2015).
A 12-month evaluation of octenidine-based wash mitts compared with bucket washing found a reduction in the prescription of antibiotics for wound infections, a reduction in infections and improvements in the quality of care. In this primary care setting, patients and healthcare staff both preferred waterless wash mitts to more traditional water-based cleansing methods (Dhoonmoon, 2020).
Recommendations
Several areas of available evidence warrant further exploration in relation to the use of octenidine wash mitts in ICU, for example the effect that the use of mitts compared with other types of decontamination (including targeted and universal) has on the reduction of HCAIs. It is also important to:
- Raise staff awareness
- Evaluate ease of use
- Consider the benefits of moving to using ‘water-free’ approaches in ICU settings.
Once the findings of the current study, which has been comparing the use of placebo versus octenidine wash mitts have been published, these will also merit further exploration.
There is significant evidence that the approach to decontamination needs to be reviewed if hospitals are to continue to address HCAIs in the face of antimicrobial resistance, especially for vulnerable patients requiring ICU care. This article has highlighted that the use of octenidine wash mitts should be considered in developing alternative approaches to prevent HCAIs.
Conclusion
HCAIs are a serious complication of hospital treatment which increase morbidity, mortality and costs, particularly for more vulnerable patients on ICU. Many HCAIs are avoidable and there is much evidence to support decontamination (universal and targeted) with an antiseptic agent to reduce microorganism reservoirs as sources of potential pathogens on the skin.
With concerns about increasing resistance to chlorhexidine, octenidine is a promising alternative that could be more effective, and offers excellent skin compatibility. In addition, the availability of octenidine-containing wash mitts meets the need for effective water-free washing in ICU.
KEY POINTS
- Patients in intensive care units (ICUs) are at a greater risk of contracting a healthcare-associated infection (HCAI) and developing complications from this than other inpatients
- Both targeted and universal decontamination have been used to help reduce microbial transmission and HCAI rates – it has been suggested that universal (or ‘routine’) decontamination may be more effective
- Octenidine may have advantages over chlorhexidine as a decontamination agent as it has fewer adverse effects and low microbial resistance
- Some healthcare facilities are introducing waterless patient washing approaches, as the presence of sinks in patient rooms has been linked to HCAIs, and there may be other benefits and staff/patient preference for ‘waterless washing’
CPD reflective questions
- What are the procedures currently undertaken in your clinical setting to prevent healthcare-associated infections? Are these targeted or universal?
- What would need to change if universal precautions were to be adopted in your setting?
- What impact would the use of water-free washing using mitts have in your setting, and what would you need to be able to implement this in your setting?
- What evidence can you collect of how washing regimens impact on your staff and patients?