Airborne Aerosol Generation During Endonasal Procedures in the Era of COVID-19: Risks and Recommendations

Otolaryngol Head Neck Surg. 2020 Sep;163(3):465-470. doi: 10.1177/0194599820931805. Epub 2020 May 26.

Abstract

Objective: In the era of SARS-CoV-2, the risk of infectious airborne aerosol generation during otolaryngologic procedures has been an area of increasing concern. The objective of this investigation was to quantify airborne aerosol production under clinical and surgical conditions and examine efficacy of mask mitigation strategies.

Study design: Prospective quantification of airborne aerosol generation during surgical and clinical simulation.

Setting: Cadaver laboratory and clinical examination room.

Subjects and methods: Airborne aerosol quantification with an optical particle sizer was performed in real time during cadaveric simulated endoscopic surgical conditions, including hand instrumentation, microdebrider use, high-speed drilling, and cautery. Aerosol sampling was additionally performed in simulated clinical and diagnostic settings. All clinical and surgical procedures were evaluated for propensity for significant airborne aerosol generation.

Results: Hand instrumentation and microdebridement did not produce detectable airborne aerosols in the range of 1 to 10 μm. Suction drilling at 12,000 rpm, high-speed drilling (4-mm diamond or cutting burs) at 70,000 rpm, and transnasal cautery generated significant airborne aerosols (P < .001). In clinical simulations, nasal endoscopy (P < .05), speech (P < .01), and sneezing (P < .01) generated 1- to 10-μm airborne aerosols. Significant aerosol escape was seen even with utilization of a standard surgical mask (P < .05). Intact and VENT-modified (valved endoscopy of the nose and throat) N95 respirator use prevented significant airborne aerosol spread.

Conclusion: Transnasal drill and cautery use is associated with significant airborne particulate matter production in the range of 1 to 10 μm under surgical conditions. During simulated clinical activity, airborne aerosol generation was seen during nasal endoscopy, speech, and sneezing. Intact or VENT-modified N95 respirators mitigated airborne aerosol transmission, while standard surgical masks did not.

Keywords: COVID-19; aerosol-generating procedure; aerosol-generating surgery; aerosolization; airborne; endoscopy; nasal endoscopy.

MeSH terms

  • Aerosols / adverse effects*
  • Betacoronavirus
  • COVID-19
  • Cadaver
  • Coronavirus Infections / transmission*
  • Endoscopy
  • Humans
  • Nose / virology*
  • Otorhinolaryngologic Surgical Procedures*
  • Pandemics
  • Particle Size
  • Personal Protective Equipment
  • Pneumonia, Viral / transmission*
  • Prospective Studies
  • Risk Factors
  • SARS-CoV-2

Substances

  • Aerosols