ネブライザの微生物汚染防止と適正試用法

Abstract

Nebulizers have been recognized as potential agents of nosocomial respiratory infection. In this study, ultrasonic and jet nebulizers were evaluated for their relative hazard as measured by the concentration of bacterial output delivered with the aerosol and the contaminant counts of components of the nebulizers. Reservoirs were seeded with a tracer organism Pseudomonas fluorescens (～10^6 CFU/ml) in distilled water. Results indicate that the jet nebulizer produces heavily contaminated bacterial aerosols (uncountable colonies in the 10sec sampling period), whereas the ultrasonic nebulizer produces 135 CFU/plate in the 60sec. The contaminant counts of components of the jet nebulizer were 10^2～10^3 times higher than those of the ultrasonic nebulizer. When the contaminated corrugated and nasal tubes were used, the contaminants stayed on those tubes. And the use of the contaminated airfilter also gave identical results. The contamination due to the flow backwards of snivel or saliva from a nasal tube or a mouthpiece was protected by the back-flow valve. No viable organisms were detected in every component of the nebulizers after the disinfection with 0.1% Tego 51 for 15 min at room temperature.