BackgroundVolume-controlled ventilation has been suggested to optimize lung deposition during nebulization although promoting spontaneous ventilation is targeted to avoid ventilator-induced diaphragmatic dysfunction. Comparing topographic aerosol lung deposition during volume-controlled ventilation and spontaneous ventilation in pressure support has never been performed. The aim of this study was to compare lung deposition of a radiolabeled aerosol generated with a vibrating-mesh nebulizer during invasive mechanical ventilation, with two modes: pressure support ventilation and volume-controlled ventilation.MethodsSeventeen postoperative neurosurgery patients without pulmonary disease were randomly ventilated in pressure support or volume-controlled ventilation. Diethylenetriaminepentaacetic acid labeled with technetium-99m (2 mCi/3 mL) was administrated using a vibrating-mesh nebulizer (Aerogen Solo®, provided by Aerogen Ltd, Galway, Ireland) connected to the endotracheal tube. Pulmonary and extrapulmonary particles deposition was analyzed using planar scintigraphy.ResultsLung deposition was 10.5 ± 3.0 and 15.1 ± 5.0 % of the nominal dose during pressure support and volume-controlled ventilation, respectively (p < 0.05). Higher endotracheal tube and tracheal deposition was observed during pressure support ventilation (27.4 ± 6.6 vs. 20.7 ± 6.0 %, p < 0.05). A similar penetration index was observed for the right (p = 0.210) and the left lung (p = 0.211) with both ventilation modes. A high intersubject variability of lung deposition was observed with both modes regarding lung doses, aerosol penetration and distribution between the right and the left lung.ConclusionsIn the specific conditions of the study, volume-controlled ventilation was associated with higher lung deposition of nebulized particles as compared to pressure support ventilation. The clinical benefit of this effect warrants further studies.Clinical trial registration NCT01879488Electronic supplementary materialThe online version of this article (doi:10.1186/s13613-016-0169-x) contains supplementary material, which is available to authorized users.
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.
In the specific conditions of the study, pulmonary drug delivery through the high-flow nasal cannula is about 1%-4% of the initial amount of drugs placed in the nebulizer, despite the higher efficiency of the VN as compared with the JN.
BACKGROUND: Recent technological advances in nebulization permit researchers to target specific parts of the lungs by modifying delivery method. The aim of this study was to compare the central and peripheral targeted modalities of administration. METHODS: Lung and regional deposition of inhaled technetium-99m diethylene triamine penta-acetic was measured by scintigraphy after peripheral and central targeted modalities of administration with an Akita device in 6 healthy subjects. RESULTS: Drug targeting nebulization delivered a large amount of drug into the peripheral part of the lung independent of the modality (outer-to-inner deposition ratio of 1.24 ؎ 0.21 vs 1.22 ؎ 0.14 for central and peripheral modalities, respectively), but there was no difference in lung deposition (whole-body deposition, 83.3 ؎ 6.5% vs 82.8 ؎ 7.3%, P ؍ .86) or regional deposition (P ؍ .77) between both modalities. The extrathoracic deposition was < 20% of the wholebody deposition, without a difference between modalities (P ؍ .86). CONCLUSIONS: This study shows for the first time that choosing 2 different specific drug targeting nebulization modes does not influence the amount of drug delivered into the lung in healthy male subjects. Moreover, the modes do not modify the site of deposition under the conditions of our study.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.