Inhaled salbutamol delivery in small children with disposable and reusable spacers: An in vitro study

Abstract

Background: Research on spacers for paediatric breathing patterns is limited, especially for disposable types, which may be a practical alternative to reusable valved holding chambers (VHC) in certain clinical settings. Methods: In vitro, the fine particle dose (FPD) of salbutamol from a pressurised metered-dose inhaler (pMDI) was tested using two paperboard spacers - DispozABLE (Diz) and LiteAire (LA) - and three reusable VHCs: AeroChamber Plus Flow-Vu (AC), EasyChamber (EC) and OptiChamber Diamond (OC). The pMDI+VHC setup was connected to a child throat model without a facemask. Salbutamol availability for inhalation was measured using a Next Generation Impactor under three paediatric breathing patterns: calm breathing (6 and 4 year olds) and obstructive breathing. Results: Median FPD in the respirable range (1-5 μm) was significantly higher for EC compared with LA, Diz and AC. Obstructive breathing increased throat deposition for all spacers, with Diz showing the highest. LA had the lowest throat deposition in calm breathing, and EC in obstructive breathing. Conclusion: Traditional VHCs, especially EC and OC, outperformed disposable spacers. Among disposables, the valved LA performed better than the valveless Diz and may offer a cost-effective, practical alternative to reusable spacers in specific scenarios.