Salbutamol MDI oropharyngeal deposition and respirable dose with and without an Aer8 spacer

Aim Spacers help address problems of user coordination and extrapulmonary drug deposition when using metered dose inhalers (MDIs). Experts recommend that every patient needing an MDI should use a spacer(1). Current spacers are underused by patients(1).The Aer8 spacer is collapsible, large volume, non-static, and environmentally friendly.We aimed to compare the oropharyngeal deposition and respirable dose of salbutamol from an MDI with and without an Aer8 spacer in order to support its evaluation by the Swedish Dental and Pharmaceutical Benefits Agency (TLV) for subsidised public medicines listing.MethodsParticle size distributions of ten sequential actuations from six samples of salbutamol MDIs were measured using a Next Generation Cascade Impactor® (NGI) and analyzed with chromatography. The particle mass for each of the NGI collection stages was measured.Te Mass Median Aerodynamic Distribution (MMAD), Geometric Standard Deviation (GSD) and Respirable Dose (with percentage Relative Standard Distribution, %RSD) of the drug particles collected were calculated.ResultsCompared with the salbutamol MDI alone, use with the Aer8 spacer reduced oropharyngeal deposition [mean 48ug (MDI alone) v 2ug/actuation (MDI+Aer8spacer)] (Table). The respirable dose(%RSD), was maintained (mean 32µg (13%) v 40µg(11%)/actuation). MMAD and GSD were unchanged (2μm/actuation). Total drug emitted was reduced by the Aer8 Spacer, (100µg v 69µg/actuation). Respirable dose and total drug emitted with the Aer8 spacer were similar to other spacers (3,4). Following evaluation, the Aer8 spacer gained TLV Sweden listing for public subsidy(2).ConclusionThe Aer8 spacer reduced salbutamol MDI oropharyngeal particle deposition while maintaining respirable dose delivery equivalent to the MDI alone. Being user and environmentally friendly, the Aer8 is an alternative to existing spacers. It is now in use in Sweden. It may be of interest to other healthcare providers. It could also be a useful tool for healthcare professionals to teach patients how to use MDIs. Implementation Science/Service Development Research Ideas on Respiratory Conditions and Tobacco Dependency Abstract Declaration of Interest Declaration of interestThis study was funded by Aer Beatha Limited. References and Clinical Trial Registry Information ReferencesVincken W et al. ERJ Open Res 2018; 4:00065-2018www.tlv.se; Aer8 spacer listing: https://www.tlv.se/ovriga-sidor/sok.html?query=Aer8&submitButton=S%C3%B6kMitchell, J, Dolovich, M.B. J Aerosol Med Pulm Drug Deliv 2012; 25(4):217-242Hall, G.L et al. Respirology 2011; 16:639-644.