Modified bronchoscopy masks mitigate aerosols during gastroscopies

Abstract Digestive endoscopy has been proven to produce aerosols (1–3). This represents a risk of infection by COVID-19 and other airborne viruses. A number of protective barriers have been proposed to minimise that risk. Continuous suction of the oral cavity (1), shielding barriers (4,5), masks (6,7), and increasing the distance between patient and endoscopist (8) have been proposed as methods to reduce the exposure of endoscopists and endoscopy staff to aerosols. Here, we present a study that uses modified bronchoscopy masks (Explorer endoscopy facemask, Intersurgical Ltd., United Kingdom) to attenuate aerosol production at the patient’s mouth (bare mask shown in Fig. 1a and in use during an upper GI endoscopy in Fig. 1b). We find that this approach offers 47% (p=0.01) reduction in particle count for particles <5μm in diameter (i.e. aerosols), which are known to spread SARS-CoV-2.