Aerosol Generating Procedures

Journal of anesthesia 

Purpose of the Study  – Quantify the amount of aerosolization during aerosol generating procedures to inform risk assessment

Study Design

-They monitored aerosolization with continuous sampling with an optical particle sizer, which allowed characterisation of aerosol generation within the zone between the patient and anaesthetist

-The extent to which COVID is transmitted as airborne is controversial 

Problems with the study

-Small sample size – used 4 ORs in the UK

-Only 19 intubations and 14 extubations 

-During intubation they use BVM and not RSI

Conclusion

– Tracheal intubation including facemask ventilation produced very low quantities of aerosolized particles – 500x less than a cough (actually state that “this study does not support the designation of elective tracheal intubation as aerosol generating”.

-Extubation, particularly when the patient coughed, produced a detectable aerosol, 15 folds greater than intubation but 35 folds less than a volatile cough .

Questions– They just say “facemask ventilation” – I think they need to be more specific.  What type of facemask did they use, what was the flow rate?

Take away –

(1)If a break in PPE then chance of acquiring COVID is probably minimal during intubation.

(2) patients coughing on us is more risk than intubation, therefore patient’s properly wearing masks can reduce this.