Taylor A, Gustafsson P
GlaxoSmithKline Research and Development, Harlow, UK.
Int J Clin Pract Suppl. 2005 Dec(149):7-12. doi: 10.1111/j.1368-504X.2005.00721.x.
Important measures of pharmaceutical performance of dry powder inhalers include total emitted dose (TED, the quantity of drug emitted from the device when used at a fixed flow rate, typically 60 l/min or the flow rate achieved at a pressure drop of 4 kPa) and fine particle mass (FPM, the quantity of drug with small particles, typically with an aerodynamic diameter of less than 5 microns emitted from the device at a fixed flow rate). There is a wide range of dry powder inhalers available. The complexity of design decisions means that dry powder inhalers are very diverse, with identical designs unlikely. It is not surprising therefore that evidence from in vitro studies shows considerable variation in pharmaceutical performance of dry powder inhalers. Although neither TED nor FPM can accurately predict in vivo performance, it may be expected that highly variable or inhalation flow sensitive in vitro behaviour will be reflected in variable performance when used by patients.
干粉吸入器药物性能的重要指标包括总释药量（TED，指在固定流速下，通常为60升/分钟或在4千帕压力降时达到的流速，使用该装置时从装置中释出的药物量）和细颗粒质量（FPM，指小颗粒药物的量，通常为空气动力学直径小于5微米的药物，在固定流速下从装置中释出）。市面上有各种各样的干粉吸入器。设计决策的复杂性意味着干粉吸入器非常多样化，不太可能有相同的设计。因此，体外研究的证据表明干粉吸入器的药物性能存在相当大的差异也就不足为奇了。虽然TED和FPM都不能准确预测体内性能，但可以预期，高度可变或对吸入流速敏感的体外行为在患者使用时会反映为性能的变化。
