COMPARISON OF 23 NEBULIZER COMPRESSOR COMBINATIONS FOR DOMICILIARY USE

We have assessed the physical and dynamic characteristics of 23 home j et nebulizer/compressor combinations currently available in the UK and Europe. The combinations were evaluated in terms of pressure-flow cha racteristics, aerosol mass distribution, volume output, electrical cos ts, and sound level. In addition, we determined the effect of nebulize r fill volume on aerosol mass distribution and volume output, One nebu lizer was used with six different compressors, and four compressors we re tested with three different nebulizers. The pressure-now relationsh ips showed a wide variation between models, as did now-rate at the neb ulizer (range 3.0-8.0 L . min(-1)), The mean+/-SD volume nebulized aft er 10 min using an initial fill volume of 2.5 and 5.0 mL was 46+/-9 an d 34+/-12%, respectively, The mass median aerodynamic diameter (MMAD) over a 5 min nebulization ranged 2.6 to 10.2 mu m. Nine of the nebuliz ations produced an MMAD of less than 5 mu m at both fill volumes, Chan ging nebulizer/compressor combinations affected flow rate, MMAD and vo lume output Sound levels varied between models. Running costs were low , with all using less than 74 kilowatt hours of energy per year. We co nclude that there is a wide variation in performance of nebulizer/comp ressor combinations for use with nebulized bronchodilators, Correct ma tching of the nebulizer/compressor is seen to be important to ensure o ptimum performance, We recommend that: 1) manufacturers of nebulizers provide information on the required flow rate at the nebulizer to prod uce the required MMAD, and the percentage of aerosol/mass contained in particles under 5 mu m; and 2) suppliers of nebulizer/compressor syst ems match the combinations more carefully to achieve optimal delivery of the nebulized drug to the patient, and that users should use recomm ended combinations.