Is flexible nasendoscopy really aerosol generating?
Reviewed by Bhav Patel

Amid the COVID-19 pandemic, the safety of office-based laryngoscopy has been a source of considerable concern, speculation and debate. Flexible nasendoscopy is a key diagnostic tool in the assessment of the ENT patient, however most healthcare providers consider this to be an aerosol generating procedure (AGP) requiring enhanced precautions to be employed. AGPs are procedures that have the potential to create aerosols in addition to those that patients regularly form from breathing, coughing, sneezing, or talking. In this study, the authors quantified the aerosolisation associated with flexible and rigid office laryngoscopy using an optical particle sizer (OPS). The OPS uses a laser system to count the number of particles in the air based on amount of light scattered by aerosols. The authors used the OPS to count aerosols generated by two healthy COVID-negative subjects while undergoing five interventions: flexible laryngoscopy; flexible laryngoscopy with humming; flexible laryngoscopy with /e/ phonation; rigid laryngoscopy; and rigid laryngoscopy with /æ/ phonation. OPS counts were compared to four positive controls – speech; breathing; /e/ phonation; and /æ/ phonation, all relative to ambient particles. There was a statistically significant increase in particle counts for breathing and /æ/ phonation relative to background. There were no significant increases in aerosol and droplet counts for flexible laryngoscopy, flexible laryngscopy with humming, flexible laryngoscopy with /e/ sound, rigid laryngscopy, and rigid laryngoscopy with /æ/ sound relative to breathing or phonation. This suggests that routine office-based laryngoscopy does not confer a greater risk than breathing or phonation. Although this study is limited in its generalisability by its small sample size of two healthy volunteers, the results of this clinical simulation are provocative and suggest that office laryngoscopy may not meet the definition criteria of an AGP. Further studies using more sophisticated aerosol counting techniques, such as scanning mobility particle spectrometry and laser diffractometry, would be valuable in generating the high‐level evidence needed to understand the aerosolisation risk of these procedures

Is Office Laryngoscopy an Aerosol‐Generating Procedure?
Rameau A, Lee M, Enver N, Sulica L.
LARYNGOSCOPE
2020;130(11):2637-42.