ABSTRACT
BackgroundThe COVID-19 pandemic has led to unprecedented demand for personal protective equipment. Shortages of surgical masks and filtering facepiece respirators has led to the extended use or re-use of single-use respirators and surgical masks by frontline healthcare workers. The evidence base underpinning such practices has been questioned. ObjectivesTo summarise guidance and synthesise systematic review evidence on extended use, re-use or reprocessing of single-use surgical masks or filtering facepiece respirators. MethodsA targeted search of the World Health Organization, European Centre for Disease Prevention and Control, the US Centers for Disease Control and Prevention, and Public Health England websites was conducted to identify guidance. Four databases (Medline, Pubmed, Epistemonikos, Cochrane Database of Systematic Reviews) and three preprint repositories (Litcovid, MedRxiv and Open Science Framework) were searched for relevant systematic reviews. Record screening and data extraction was conducted by two reviewers. Quality of included systematic reviews was appraised using the AMSTAR-2 checklist. Findings were integrated and narratively synthesised to highlight the extent to which key claims in guidance documents were supported by research evidence. ResultsSix guidance documents were identified. All note that extended use or re-use of single-use surgical masks and respirators (with or without reprocessing) should be considered only in situations of critical shortage. Extended use was generally favoured over re-use because of reduced risk of contact transmission. Four high-quality systematic reviews were included: three focused on reprocessing (decontamination) of N95 respirators and one focused on reprocessing of surgical masks. There was limited evidence on the impact of extended use on masks and respirators. Vaporised hydrogen peroxide and ultraviolet germicidal irradiation were highlighted as the most promising reprocessing methods, but evidence on the relative efficacy and safety of different methods was limited. We found no well-established methods for reprocessing respirators at scale. ConclusionsThere is limited evidence on the impact of extended use and re-use of surgical masks and respirators. Where extended use or re-use is being practiced, healthcare organisations should ensure that policies and systems are in place to ensure these practices are carried out safely and in line with available guidance.
ABSTRACT
ObjectivesIn the context of the Covid-19 pandemic, to identify the range of filtering respirators that can be used in patient care and synthesise evidence to guide the selection and use of different respirator types. DesignComparative analysis of international standards for filtering respirators and rapid review of their performance and impact in healthcare. Data sourcesWebsites of international standards organisations, Medline and EMBASE (final search 11th May 2020), with hand-searching of references and citations. Study selectionGuided by the SPIDER tool, we included studies whose sample was healthcare workers (including students). The phenomenon of interest was respirators, including disposable and reusable types. Study designs including cross-sectional, observational cohort, simulation, interview and focus group. Evaluation approaches included test of respirator performance, test of clinician performance or adherence, self-reported comfort and impact, and perceptions of use. Research types included quantitative, qualitative and mixed methods. We excluded studies comparing the effectiveness of respirators with other forms of protective equipment. Data extraction, analysis and synthesisTwo reviewers extracted data using a template. Suitability for inclusion in the analysis was judged by two reviewers. We synthesised standards by tabulating data according to key criteria. For the empirical studies, we coded data thematically followed by narrative synthesis. ResultsWe included relevant standards from 8 authorities across Europe, North and South America, Asia and Australasia. 39 research studies met our inclusion criteria. There were no instances of comparable publications suitable for quantitative comparison. There were four main findings. First, international standards for respirators apply across workplace settings and are broadly comparable across jurisdictions. Second, effective and safe respirator use depends on proper fitting and fit-testing. Third, all respirator types carry a burden to the user of discomfort and interference with communication which may limit their safe use over long periods; studies suggest that they have little impact on specific clinical skills in the short term but there is limited evidence on the impact of prolonged wearing. Finally, some clinical activities, particularly chest compressions, reduce the performance of filtering facepiece respirators. ConclusionA wide range of respirator types and models is available for use in patient care during respiratory pandemics. Careful consideration of performance and impact of respirators is needed to maximise protection of healthcare workers and minimise disruption to the delivery of care.
