Abstract
Background: Nebulizers have been associated with bacterial and viral contamination likely from drooling or expulson of oral secretions into the nebulizer mouthpiece. We hypothesized that simulated “drooling” could result in contamination of the nebulizer medication resulting in aerosolization of potential pathogens.
Method: We evaluated four nebulizers: Continuous jet nebulizer (CJN: MistyMax, Allegiance, USA), breath enhanced (BEN:LC Sprint; Pari, Germany), breath actuated (BAN; AeroEclipse Monaghan/Trudell, Canada) and vibrating mesh nebulizer (VMN; Aerogen with Ultra, Aerogen Ltd, Galway, Ireland) operated per manufacturer recommendations with 3 mL of NSS. Pseudomonas aeruginosa broth (2 mL) was pipetted into the mouthpiece of each nebulizer in an upright postion simulating a patient drooling into the device. Aerosol was produced for 30-60 seconds and collected on Triptic Soy Agar (TSA) plate, prior, immeadiately, and 4-5 hours post instillation. Colony counts were done post incubation (3-5 days).
Results: P. aeruginosa colony counts prior, immediately, and four hours after instillation; BAN (0, 110, and 122 CFU/m); and BEN (0, Too Numerous To Count (TNC), and TNC), VMN: (0, 0, and 0 CFU/mL) and CJN (0, 0, and 0 CFU/mL), respectively.
Conclusions: Nebulizer type and design influence impact of pathogen containing fluids passing through the mouthpiece contaminating the aerosol generated.