Relative performance of nebulizers used in acute care wards

Abstract

Nebulizers used in acute care wards must be relied upon to rapidly deliver aerosols to patients who may be suffering an asthma attack. Both the respirable delivered dose and the respirable output rate are of significance for the rapid delivery of therapeutic doses to the target sites of action in the lungs. We tested 4 nebulizers used in acute care wards, in vitro, to determine their aerosol delivery performance into simulated adult breathing.

Six of each nebulizer brand (Table 1; SSD -Philips SideStream Disposable, HMM -Hudson Micro Mist, AMF -AirLife Misty Fast, SND-Salter Nebutech Disposable 8960) were tested once for particle size and output. Each nebulizer was tested with salbutamol sulphate (Salamol 5 mg/ 2.5 mL) for particle size (Malvern Spraytec) and separately for delivered dose. Delivered dose was determined using a filter connected to a breathing simulator set to generate a sine wave (Vt=500 mL, f=15 bpm, I:E=1:1). Nebulizers were run until sputter plus 60 s. Salbutamol was quantitated by high performance liquid chromatography.

There was a wide range in performance, nebuilzers with the shortest nebulization time delivered the lowest respirable delivered doses and lowest respirable output rates. Speed of treatment in acute cae should be assessed using respirable output rate not nebulization time alone.