A quantitative evaluation of aerosol generation during supraglottic airway insertion and removal

The WHO has developed a list of aerosol-generating procedures that healthcare organisations throughout the world have used as a framework for development of their guidelines. Supraglottic airways are used in the majority of the approximately 2.7 million general anaesthetics performed in the UK each year. In a UK survey in October 2020, 40% of responding hospitals reported that supraglottic airway removal, even in low COVID-19 risk pathways, is restricted exclusively to the operating theatre (rather than being performed in a recovery area), indicating the presence of policies that assume it is an aerosol-generating procedure. However, uncertainty remains as to whether insertion or removal of a supraglottic airway generates aerosols.

Given the uncertain balance of potential risks and benefits associated with the protective strategies put in place to limit airborne viral transmission, this new paper from Shrimpton et al. aimed to directly assess airborne particle emission during insertion and removal of supraglottic airways. They used real-time measures of aerosol generation with an optical particle sizer in a working operating theatre environment and compared the measured levels with reference to those generated by a volitional cough and the patient’s own breathing.

Joining two of the authors was our fellow, Craig Lyons as well as Laura Duggan who is an Editor of Anaesthesia.