Department of Mechanical and Nuclear Engineering and Virginia Commonwealth University, Richmond, Virginia.
Department of Pharmaceutics, Virginia Commonwealth University, Richmond, Virginia.
J Aerosol Med Pulm Drug Deliv. 2020 Apr;33(2):83-98. doi: 10.1089/jamp.2019.1540. Epub 2019 Aug 29.
Dry powder inhalers (DPIs) offer a number of advantages, such as rapid delivery of high-dose inhaled medications; however, DPI use in children is often avoided due to low lung delivery efficiency and difficulty in operating the device. The objective of this study was to develop a high-efficiency inline DPI for administering aerosol therapy to children with the option of using either an oral or trans-nasal approach. An inline DPI was developed that consisted of hollow inlet and outlet capillaries, a powder chamber, and a nasal or oral interface. A ventilation bag or compressed air was used to actuate the device and simultaneously provide a full deep inspiration consistent with a 5-year-old child. The powder chamber was partially filled with a model spray-dried excipient enhanced growth powder formulation with a mass of 10 mg. Device aerosolization was characterized with cascade impaction, and aerosol transmissions through oral and nasal models were assessed. Best device performance was achieved when all actuation air passed through the powder chamber (no bypass flow) resulting in an aerosol mean mass median aerodynamic diameter (MMAD) <1.75 μm and a fine particle fraction (<5 μm) ≥90% based on emitted dose. Actuation with the ventilation bag enabled lung delivery efficiency through the nasal and oral interfaces to a tracheal filter of 60% or greater, based on loaded dose. In both oral and nose-to-lung (N2L) administrations, extrathoracic depositional losses were <10%. In conclusion, this study has proposed and initially developed an efficient inline DPI for delivering spray-dried formulations to children using positive pressure operation. Actuation of the device with positive pressure enabled effective N2L aerosol administration with a DPI, which may be beneficial for subjects who are too young to use a mouthpiece or to simultaneously treat the nasal and lung airways of older children.
干粉吸入器（DPIs）具有许多优点，例如能够快速输送高剂量吸入药物；然而，由于肺部输送效率低且操作装置困难，DPIs 在儿童中的使用往往受到限制。本研究的目的是开发一种高效的在线 DPI，为儿童提供气雾剂治疗，可选择经口或经鼻途径使用。 开发了一种在线 DPI，它由空心入口和出口毛细管、粉末室和鼻或口腔接口组成。通风袋或压缩空气用于启动装置，并同时提供符合 5 岁儿童的完全深吸气。粉末室部分填充了一种模型喷雾干燥赋形剂增强生长粉末制剂，质量为 10mg。通过级联撞击对粉末室的气溶胶化进行了特征描述，并评估了通过口腔和鼻腔模型的气溶胶传输。 当所有的驱动空气都通过粉末室（无旁路气流）时，装置的性能最佳，导致气溶胶的平均质量中值空气动力学直径（MMAD）<1.75μm，且基于发射剂量的细颗粒分数（<5μm）≥90%。使用通风袋进行驱动使得通过鼻腔和口腔接口向气管过滤器输送的效率达到 60%或更高，基于加载剂量。在口腔和鼻到肺（N2L）给药中，胸外沉积损失均<10%。 总之，本研究提出并初步开发了一种高效的在线 DPI，用于使用正压操作向儿童输送喷雾干燥制剂。通过正压驱动装置，可有效进行 N2L 气溶胶给药，这对于太小而无法使用吸嘴或同时治疗年龄较大儿童的鼻腔和肺部气道的患者可能有益。
