Purpose: To compare in vivo the total and regional pulmonary deposition of aerosol particles generated by a new system combining a vibrating-mesh nebulizer with a specific valved holding chamber and constant-output jet nebulizer connected to a corrugated tube.
Methods: Cross-over study comparing aerosol delivery to the lungs using two nebulizers in 6 healthy male subjects: a vibrating-mesh nebulizer combined with a valved holding chamber (Aerogen Ultra®, Aerogen Ltd., Galway, Ireland) and a jet nebulizer connected to a corrugated tube (Opti-Mist Plus Nebulizer®, ConvaTec, Bridgewater, NJ). Nebulizers were filled with diethylenetriaminepentaacetic acid labelled with technetium-99 m (99mTc-DTPA, 2 mCi/4 mL). Pulmonary deposition of 99mTc-DTPA was measured by single-photon emission computed tomography combined with a low dose CT-scan (SPECT-CT).
Results: Pulmonary aerosol deposition from SPECT-CT analysis was six times increased with the vibrating-mesh nebulizer as compared to the jet nebulizer (34.1 ± 6.0% versus 5.2 ± 1.1%, p < 0.001). However, aerosol penetration expressed as the three-dimensional normalized ratio of the outer and the inner regions of the lungs was similar between both nebulizers.
Conclusions: This study demonstrated the high superiority of the new system combining a vibrating-mesh nebulizer with a valved holding chamber to deliver nebulized particles into the lungs as comparted to a constant-output jet nebulizer with a corrugated tube.
Trial registration: ClinicalTrials.gov NCT02298101.
Keywords: Aerosol delivery; Healthy subjects; Single photon emission computed tomography; Spacer; Vibrating-mesh nebulizer.