Aerosol-generating behaviours in speech pathology clinical practice: A systematic literature review

Abstract

Objective To evaluate the evidence of aerosol generation across tasks involved in voice and speech assessment and intervention, to inform better management and to reduce transmission risk of such diseases as COVID-19 in healthcare settings and the wider community. Design Systematic literature review. Data sources and eligibility Medline, Embase, Scopus, Web of Science, CINAHL, PubMed Central and grey literature through ProQuest, The Centre for Evidence-Based Medicine, COVID-Evidence and speech pathology national bodies were searched up until August 13th, 2020 for articles examining the aerosol-generating activities in clinical voice and speech assessment and intervention within speech pathology. Results Of the 8288 results found, 39 studies were included for data extraction and analysis. Included articles were classified into one of three categories: research studies, review articles or clinical guidelines. Data extraction followed appropriate protocols depending on the classification of each article (e.g. PRISMA for review articles). Articles were assessed for risk of bias and certainty of evidence using the GRADE system. Six behaviours were identified as aerosol generating. These were classified into three categories: vegetative acts (coughing, breathing), verbal communication activities of daily living (speaking, loud voicing), and performance-based tasks (singing, sustained phonation). Certainty of evidence ranged from very low to moderate with variation in research design and variables. Conclusions This body of literature helped to both identify and categorise the aerosol-generating behaviours involved in speech pathology clinical practice and confirm the low level of evidence throughout the speech pathology literature pertaining to aerosol generation. As many aerosol-generating behaviours are common human behaviours, these findings can be applied across healthcare and community settings. Systematic review registration Registration number CRD42020186902 with PROSPERO International Prospective Register for Systematic Reviews.

Aerosol generation during coughing: an observational study

“…The concentrations we measured are consistent with a recent systematic review. 8 However, our study complements previous studies with exposure-based measurements in the operating theatre and systematic distance-dependent evaluation, which is one of the most significant factors in aerosol exposure. 8 , 24 The large range and individual differences of the particle concentrations in our study are seen typically in respiratory activities and related to the heterogeneity of the individual's aerosol generation.…”

“… 8 However, our study complements previous studies with exposure-based measurements in the operating theatre and systematic distance-dependent evaluation, which is one of the most significant factors in aerosol exposure. 8 , 24 The large range and individual differences of the particle concentrations in our study are seen typically in respiratory activities and related to the heterogeneity of the individual's aerosol generation. 28 , 29 However, considering that no difference between volitional and involuntary coughs was observed, and that coughs measured on different days and in different operating theatres are comparable ( Figure 2 ), we conclude that the presented data are representative regarding the exposure of average aerosol concentration generated during coughing.…”

“…[5][6][7] As the understanding of humans as aerosol generators during normal respiratory activities has increased, the term 'aerosol-generating behaviours' has been proposed to be used alongside 'aerosol-generating procedures'; abandonment of the classification of medical procedures as aerosol-generating procedures has even been proposed. 8 However, the aerosol-generating procedure classification has been widely used in hospitals globally. Data indicate that surgical procedures involving the mucous membranes and respiratory tract have been postponed during the coronavirus disease 2019 (Covid-19) pandemic for fear of infection.…”

Effect of frequency and amplitude of respiratory activity on aerosol emissions

“…It is now accepted that respiratory activities, such as coughing, talking, singing and exercising also generate significant aerosols and are associated with disease transmission [1,4]. Paradoxically, respiratory therapies, designated as aerosol-generating procedures, including continuous positive airway pressure (CPAP), noninvasive ventilation (NIV) and high-flow nasal oxygen (HFNO) have now been shown not to be significant sources of aerosols in several studies, which measured exhaled particles generated by healthy subjects during a range of respiratory activities with and without therapies [4,5].…”

Electropalatography (EPG) activities in Japan and the impact of the COVID‐19 pandemic on EPG research and therapy: A report of presentations at the 7th EPG Symposium

“…Moreover, during the production of short sentences, the ‘airflow is more jerky and changes direction, depending on the sound emitted’; for example, for a voiceless bilabial plosive /p/, ‘a conical jet with average velocities of tens of centimetres per second and over long distances of about 1 m’ was observed (Abkarian et al., 2020 : 25239). Breathing and speaking are the main activities that take place during speech research and speech therapy (Chacon et al., 2021 ), although coughing and sneezing may also occur, with the result that appropriate measures are needed to protect research participants, researchers, clinicians and clients if the research and therapy activities are to be carried out as scheduled.…”