The therapeutic effect of dry powder inhaler (DPI) formulations can be enhanced by understanding several factors that control the behavior or deposition of inhaled particles in the airways. Computational fluid dynamics (CFD) simulation was performed to predict the behavior and deposition of DPI formulations using a pulmonary model generated on the basis of computed tomography scans of a subject's airway. The effects of inhalation procedures and characteristics, such as flow rate and breath holding, on particle behavior and deposition in the airways were examined. The rate of airflow in the bifurcation area of bronchi was reduced to under 28.3 L/min because, in general, the diameter of the right bronchus is larger than that of the left bronchus in human bronchi. The region of particle deposition differed depending on the rate of airflow. The number of particles deposited in the bronchi decreased upon performing exhalation without breath holding. The results indicated that the turbulence following breath holding promoted particle deposition in the airways. CFD simulation suggested that breath holding is one of the most important factors for enhancing the therapeutic effect of DPI formulations.

通过了解一些控制吸入颗粒在气道中的行为或沉积的因素，可以增强干粉吸入器（DPI）制剂的治疗效果。使用基于受试者气道的计算机断层扫描扫描生成的肺部模型，进行了计算流体动力学（CFD）模拟，以预测DPI制剂的行为和沉积。检查了吸入程序和特征（例如流速和屏气）对颗粒行为和气道沉积的影响。支气管分叉区域的气流速率降低到28.3 L / min以下，因为通常人支气管的右支气管直径大于左支气管直径。颗粒沉积的区域根据气流速率而有所不同。在不屏气的情况下呼气时，沉积在支气管中的颗粒数量减少了。结果表明，屏气后的湍流促进了颗粒在呼吸道中的沉积。CFD模拟表明屏气是增强DPI制剂治疗效果的最重要因素之一。