Department of Internal Medicine, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.
Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
Sci Rep. 2020 Apr 29;10(1):7271. doi: 10.1038/s41598-020-64235-6.
Optimal peak inspiratory flow rate (PIFR) is crucial for optimizing dry powder inhaler (DPI) effectiveness for chronic obstructive pulmonary disease (COPD). This study provide an insight that there was a substantial proportion of improper PIFRs (not only insufficient but also excessive) among COPD patients using DPIs. We enrolled 138 COPD patients from a medical center in Taiwan and measured PIFRs against different internal resistances of DPIs. Proportion of excessive, optimal, suboptimal, and insufficient PIFRs were 2%, 54%, 41%, 3%, respectively, against medium-high resistance; 2%, 77%, 20%, 1%, respectively, against medium resistance; 27%, 63%, 9%, 1%, respectively, against medium-low resistance; and 42%, 57%, 1%, 0%, respectively, against low resistance (p < 0.01). Although most PIFRs against medium-high (54%), medium (77%), medium-low (63%) and low (57%) resistance were optimal, a substantial proportion of PIFRs against low resistance were excessive (42%, p < 0.01), irrespective of age, body-mass index, dyspnea severity score, and COPD severity. Insufficient PIFRs were infrequent, but suboptimal/insufficient PIFRs were most prevalent in patients older than 75 years than in younger patients (36% vs. 56%, p = 0.036) against medium-high resistance. Regularly monitoring PIFRs against the specific resistance of the DPIs and instructing patients to employ a proper inspiration effort may help to optimize the effects of DPIs.
优化峰值吸气流速（PIFR）对于优化慢性阻塞性肺疾病（COPD）患者的干粉吸入器（DPI）疗效至关重要。本研究表明，在使用 DPI 的 COPD 患者中，存在相当比例的 PIFR 不当（不仅不足，而且过多）。我们从台湾一家医学中心招募了 138 名 COPD 患者，并针对不同的 DPI 内部阻力测量了 PIFR。过高、最佳、欠佳和不足的 PIFR 比例分别为：中高阻力时，分别为 2%、54%、41%、3%；中阻力时，分别为 2%、77%、20%、1%；中低阻力时，分别为 27%、63%、9%、1%；低阻力时，分别为 42%、57%、1%、0%（p<0.01）。尽管大多数中高（54%）、中（77%）、中低（63%）和低（57%）阻力的 PIFR 最佳，但相当比例的低阻力 PIFR 过高（42%，p<0.01），与年龄、体重指数、呼吸困难严重程度评分和 COPD 严重程度无关。不足的 PIFR 并不常见，但年龄大于 75 岁的患者比年轻患者更常见欠佳/不足的 PIFR（36% vs. 56%，p=0.036）对抗中高阻力。定期监测针对 DPI 特定阻力的 PIFR 并指导患者使用适当的吸气力，可能有助于优化 DPI 的效果。
