4 Committee discussion
4.1 Although the studies report a reduction in bloodstream infections with Curos, there are differences in the way in which this is measured between studies. The clinical experts explained that this variation in measuring and reporting bloodstream infections is a common problem in both clinical studies and NHS practice. The committee considered that this makes any judgement about the overall effectiveness of Curos less certain. The committee acknowledged the low quality of the evidence, noting that the before-and-after design of the studies was likely to introduce bias. Most of the studies were done outside of the UK so their generalisability to NHS practice is uncertain. The committee noted that the studies were insufficiently powered to detect any benefit with Curos independent of the existing bundle of care for preventing infections. The studies also provide few details about any other infection prevention techniques that were used.
4.2 In NHS practice, Curos would be used as part of the standard bundle of care for preventing infections. The committee proposed that more NHS-based evidence was needed, exploring the potential clinical benefits of Curos when used as part of a bundle of care for preventing infections.
There is insufficient evidence to support the adoption of Curos for any subgroups but those at high risk of infection are likely to benefit most
4.3 The committee concluded that because of the heterogeneity of the clinical evidence it could not recommend the adoption of Curos in any subgroup of people. Despite the lack of evidence, the committee considered that it was plausible Curos could provide benefits in certain situations. The external assessment centre (EAC) highlighted the fact that the evidence suggests that the benefits of Curos were most likely to be seen in people who are at high risk of infection. The clinical experts explained that there are a number of factors that can affect infection rates, including the nature of the underlying disease, the healthcare environment, the type of line in place, the nature of the administered drug or fluid and the frequency of administrations needed. The infection rate is also affected by staff compliance with infection reduction protocols. The clinical experts advised that people who are immunocompromised, such as those having bone marrow transplants or treatment for cancer, are likely to have a higher infection risk. The clinical experts also highlighted the potential benefits of using Curos in a community setting where many people have long-term vascular access devices in place. The committee agreed that future research should focus on people at high risk of infection, including those in community settings.
4.4 The clinical experts explained that implementing any new infection prevention strategy is likely to increase staff compliance with protocols already in place, particularly when practice is being audited. The committee noted that compliance is likely to vary over time and that this was not adequately captured by the clinical evidence. The clinical experts also advised that compliance with standard infection prevention protocols varies in NHS practice and in some cases may be as low as 20%. The committee acknowledged that using Curos may increase compliance, but there was insufficient evidence for this.
4.5 Curos is a single-use device: that is, the cap must be replaced each time the line is accessed. The clinical experts agreed that there is a potential risk of Curos being re-used when the line is accessed, but they advised that any misuse can be avoided through regular staff training.
4.6 The clinical experts noted that carefully planned stock control is important to ensure the continued availability of Curos. The company confirmed that Curos is readily available and that the NHS supply chain holds a 3- to 4-week stock. The committee raised concerns about the sustainability of the technology and if disposing the caps (which are not currently recyclable) would have a negative environmental impact. The company stated that Curos caps are treated as clinical waste on disposal.
4.7 The committee agreed with the EAC that the reliability of the cost modelling was limited because of the uncertainty in the clinical evidence. Clinical expert advice was mixed: although some experts agreed that Curos may save time compared with manual disinfection, others noted that compliance with manual disinfection protocols is very low in practice and using Curos would be unlikely to free up any staff time. The committee accepted the EAC's revisions to the cost model but concluded that further evidence is needed to show if using Curos releases staff resources or not.
4.8 The main driver in the cost model was baseline infection rate (that is, the higher the baseline infection rate, the greater the potential cost savings with Curos). The clinical experts explained that bloodstream infection rates are highly variable both within and between hospitals, and the way in which hospitals measure and report bloodstream infections varies. Having reviewed the cost evidence and accepting the uncertain clinical benefits, the committee concluded that more robust data were needed to understand the potential resource impact of using Curos in the NHS.
4.9 The committee concluded that further research would help resolve the uncertainties about the potential benefits of using Curos. The research should determine if Curos adds clinical value to the standard bundle of care for preventing infections when using needleless connectors. It should focus on people at high risk of infection. A community-based trial should be considered, and a prospective and randomised trial design would be appropriate to limit bias. The research should provide data to inform cost modelling and should be designed with a timeframe that would provide useful information before this guidance is reviewed.