School of Pharmacy & Biomolecular Sciences, Liverpool John Moores University, Byrom Street, Liverpool, L3 3AF, UK.
Pharm Res. 2010 Jan;27(1):175-86. doi: 10.1007/s11095-009-9994-z. Epub 2009 Nov 10.
This study investigated the effect of oropharyngeal geometry on inhaled aerosol characteristics via pressurised metered dose inhalers (pMDIs), both with or without spacers.
Seven adult oropharyngeal models with different centreline lengths, total volumes, and degrees of constriction were employed as induction ports for a laser diffraction particle size analyser and cascade impactor. Particle size change over time, mass median aerodynamic diameter (MMAD), average median volume diameter (D(V)50), inhaled doses, and oropharyngeal depositions (percentage of the nominal dose) for aerosols via suspension and ultrafine pMDIs with or without spacers at 30 l/min airflow were determined.
Variations in oropharyngeal geometry caused significant variations in inhaled particle size distributions, doses, oropharyngeal drug depositions, and particle size change over time when pMDIs were used without spacers. However, inhaled aerosol characteristics had marginal variations for the ultrafine pMDI plus large volume spacer (MMAD range: 0.69-0.78 microm, D(V)50 range: 1.27-1.36 microm, inhaled dose range: 46.46-52.92%). It was found that the amounts of inhaled aerosol particles with aerodynamic size of less than 0.83 microm via pMDIs plus large volume spacer were slightly affected by the oropharyngeal geometry.
Inhaling ultrafine aerosols via spacers may reduce the effect of oropharyngeal geometry on inhaled aerosol properties.
本研究通过加压定量吸入器（pMDI），包括带和不带储雾罐，考察口咽几何形状对吸入气溶胶特性的影响。
7 个成人口咽模型，具有不同的中轴线长度、总体积和收缩程度，用作激光衍射粒度分析仪和级联撞击器的诱导端口。悬浮液和超细 pMDI 在 30 l/min 气流下，无论是否带储雾罐，测定时间过程中的粒径变化、质量中值空气动力学直径（MMAD）、平均中值体积直径（D(V)50）、吸入剂量和口咽沉积率（名义剂量的百分比）。
口咽几何形状的变化导致在不带储雾罐使用 pMDI 时，吸入的颗粒大小分布、剂量、口咽药物沉积和粒径随时间的变化有显著差异。然而，对于超细 pMDI 加大容量储雾罐，吸入气溶胶特性仅有微小变化（MMAD 范围：0.69-0.78 微米，D(V)50 范围：1.27-1.36 微米，吸入剂量范围：46.46-52.92%）。发现通过带大容量储雾罐的 pMDI 吸入的空气动力学粒径小于 0.83 微米的吸入气溶胶颗粒的量受口咽几何形状的影响较小。
通过储雾罐吸入超细气溶胶可能会降低口咽几何形状对吸入气溶胶性质的影响。
