An in vitro investigation into the release of fugitive medical aerosols into the environment during manual ventilation

During manual resuscitation, nebulizer therapy may be used to deliver therapeutics to patients in respiratory distress. However, the devices used to generate and deliver these medical aerosols have the potential to release these therapeutics into the local environment and expose caregivers to unwanted medical aerosols. To quantify the levels of fugitive medical aerosol released into the environment during aerosol drug delivery using a manual resuscitation bag with and without filtration. Time-varying fugitive aerosol concentrations were measured using an aerodynamic particle sizer placed at a position designed to mimic a caregiver. Two nebulizer types were assessed, a vibrating mesh nebulizer and a jet nebulizer. The aerosol dose delivered to the simulated patient lung was also quantified. Filtration of the exhalation port of the manual resuscitation bag was seen to reduce fugitive medical aerosols to ambient levels for both nebulizer types. The vibrating mesh nebulizer delivered the greatest quantity of aerosol to the simulated adult patient (18.44 ± 1.03% versus 3.64 ± 0.26% with a jet nebulizer). The results highlight the potential for exposure to fugitive medical aerosols released during the delivery of aerosol therapy with a manual resuscitation bag and also the potential for significant variation in patient lung dose depending on nebulizer type.