Objectives: Different commercially available nebulizers and compressors are available. However, the optimal combination for drug delivery is unknown.
Methods: Flow rates of five different compressors (n = 3/compressor) tested alone and in combination with five different commercial nebulizers (n = 9 of each brand of nebulizer) were evaluated. Thereafter, the performances of the different nebulizers were evaluated using 2.5 mg albuterol solution (0.5 mL) added to 2.5 mL saline at flow rates of 2, 3, 4, and 5 L/minute using a laser particle analyzer. Volume median diameter and percentage of particles in the respirable range (1-5 microm) were calculated from this data. Time for nebulization (in seconds) and residual volume (in milliliters) were also recorded.
Results: The mean flow rates for the compressors evaluated without a nebulizer attached ranged from 6.6 L/minute (LifeCare Freedom-neb; LifeCare International, Lafayette, CO) to 12.2 L/minute (DeVilbiss Pulmo-Aide; DeVilbiss Health Care, Somerset, PA). Flow rates for the nebulizer/compressor combinations ranged from 2.08 L/minute (Pari LC Jet Proneb; Pari Respiratory Equipment, Richmond, VA) to 5.42 L/minute (Puritan Bennett Raindrop; Puritan Bennett, Lenexa, KS/Omron Compare; Omron, Health Care,Vernon Hills, IL). Using the repeated measure ANOVA model, the interaction between flow rate and device was significant (P < 0.001) for both percentage of particles in the respirable range and log volume median diameter. It was observed that the percentage of particles in the respirable range for the Pari LC Jet did not increase across flow rates in contrast to the other 4 nebulizers. All comparisons to the Pari LC Jet at 2 L/minute were significant.
Conclusions: Marked variability exists in the flow rates among different commercially available compressors used for home nebulization of inhaled pulmonary medications. Different nebulizer/compressor combinations have markedly different performance characteristics which could result in different efficacy and safety profiles of the medications being administered via these devices. We recommend that this type of information be used as a starting point for selecting different nebulizer/compressor combinations. Further clinical evaluation is warranted.