Samuel J. Reade MBChB, MRes, Ahmad Bassam MBBS, BMedSci, Wisam Al-Bassam FCICM, MBChB, Umesh Kadam MD, MRCP UK, FCICM
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引用次数: 0
Abstract
Aim/objectives
Fit testing of N95/FFP2 respirators is universally recommended before exposure to airborne infectious diseases such as COVID-19. Respirator supply shortage in the COVID-19 pandemic encouraged extended-use for up to 4 h, despite uncertainty about seal integrity over time. The aim of our study was to assess N95 seal integrity after at least 2 h of continuous clinical use in the intensive care unit (ICU). We hypothesised that seal integrity would deteriorate over time, with variability between respirator shapes.
Methods
A prospective cohort study of healthcare workers in a metropolitan ICU setting in Australia between April 2021 and August 2022. Following consent and screening, participants underwent qualitative fit testing in the ICU, and fit tests were repeated following a continuous period of at least 2-h usage. The primary outcome was N95 fit-test failure rate measured by qualitative fit testing of >2 h compared to baseline. Secondary outcomes evaluated effects of respirator shape, demographic characteristics, and duration of respirator use on respirator fit after 2 h use.
Results
Fifty-one participants were recruited and consented. Six participants were excluded; four failed baseline fit test, one could not taste saccharin, and one did not complete 2 h of usage. Fourteen of 45 participants (∼31%) failed the extended-use fit test (median duration: 2 h 10 min [interquartile range: 2:07–2:20]). Fit-test rates differed between respirator shapes; three-piece flat-fold respirators had lower failure rates (6/32; 19%) than duckbill-shaped respirators (6/11; 55%) p = 0.046. No other demographic characteristic or respirator shape was significantly associated with increased failure rate.
Conclusions
Following 2 h of use, approximately 30% of participants failed repeat fit testing, suggesting incomplete respiratory protection. Three-piece flat-fold respirators outperformed duckbill respirators. Extended use of respirators, even without respirator reuse, may put healthcare workers at risk of inadequate respiratory protection, in particular when using duckbill-shaped respirators.
期刊介绍:
Australian Critical Care is the official journal of the Australian College of Critical Care Nurses (ACCCN). It is a bi-monthly peer-reviewed journal, providing clinically relevant research, reviews and articles of interest to the critical care community. Australian Critical Care publishes peer-reviewed scholarly papers that report research findings, research-based reviews, discussion papers and commentaries which are of interest to an international readership of critical care practitioners, educators, administrators and researchers. Interprofessional articles are welcomed.