The ISO 27427:2013 (E) standard states that jet nebulizer performance should be compared by the percentage of fill volume which is delivered. (1) Should mesh nebulizers be assessed in the same way?
In this study, we compared 2 mesh nebulizers: the Aeroneb Go and eFlow. The 2 mesh nebulizers were compared in terms of particle size by laser diffraction and delivered dose, respirable delivered dose, and efficiency using simulated breathing patterns with different inhalation:exhalation ratios. To characterize the nebulizers, 2.5 mL of 5 mg/2.5 mL salbutamol sulphate solution was used. Three of each nebulizer type were tested once, resulting in n=3. A filter was used and placed between the ASL 5000 breathing simulator and the nebulizer to capture the aerosol available to the patient. Aerosol deposited on the filter was analyzed by high performance liquid chromatography. Respirable delivered dose and respirable delivered dose efficiency were subsequently calculated from the particle size, delivered dose and nebulizer fill. All percentages are expressed relative to nebulizer fill. The delivered dose efficiency for the eFlow nebulizer ranged from 28.17% to 14.15% across the breathing patterns, and for the Aeroneb Go nebulizer it ranged from 39.13% to 19.16%. Efficiency in terms of respirable delivered dose ranged from 18.20% to 9.14% for the eFlow nebulizer compared with 25.62% to 12.55% for the Aeroneb Go nebulizer across the breathing patterns. The Aeroneb Go nebulizer was the more efficient nebulizer in terms of delivered dose efficiency and respirable delivered dose efficiency. This variability suggests that mesh nebulizers need the same performance tests as jet nebulizers.