Speech intelligibility in respiratory protective equipment - Implications for verbal communication in critical care

Respiratory protective equipment (RPE) such as filtering facepiece respirators, elastomeric respirators and powered air-purifying respirators are routinely worn in the critical care unit as a component of personal protective equipment (PPE) when caring for patients with coronavirus disease 2019 (COVID-19). It is the authors' anecdotal experience that RPE may, however, inadvertently interfere with verbal communication between critical care staff. The literature pertaining to the effects of RPE wear on verbal communication was therefore reviewed. A literature search returned 98 articles, and 4 records were identified from other sources; after screening for content relevancy, 15 experimental studies were included in the narrative synthesis. Previous studies in both healthcare and other occupational settings suggest a detrimental impact on speech intelligibility, varying according to RPE type and test conditions. The effects of background noise and potential for increased cognitive load through compensatory behaviours are also identified. The clinical significance of these effects remains uncertain though, as evidence measuring clinical outcomes or errors is lacking. Mitigating strategies include increasing speech intelligibility through environmental changes and technology; modifying verbal communication strategies; and decreasing reliance on verbal communication where possible.