Malmberg Leo Pekka, Kauppi Paula, Mäkelä Mika J
Department of Clinical Physiology, Skin and Allergy Hospital, Helsinki University Hospital, Helsinki, Finland.
University of Helsinki, Helsinki, Finland.
Clin Physiol Funct Imaging. 2018 Sep;38(5):903-906. doi: 10.1111/cpf.12498. Epub 2018 Jan 17.
Recent technical recommendations on bronchial challenge testing aim at standardized assessment of provocative dose of causing 20% decrease in FEV1 (PD20). The aim of this study was to investigate the effect of mode of nebulization on the output of a computerized dosimeter (APS) and to compare PD20 obtained by two different dosimetric systems in vivo. The output of the APS system was tested during continuous nebulization, and using simulated breaths, for intermittent actuations with four different durations. Using output data, a modified methacholine challenge protocol was applied for APS and compared with a standard set-up using Spira dosimeter in 14 asthmatic patients attending duplicate methacholine challenges using both systems, within median (range) 3 (1-6) days apart. The calculated output (mg min ) with all the intermittent mode settings was significantly higher (P<0·001) than in the continuous mode, and in the intermittent mode, the output was dependent of the pulse duration. The PD20 values assessed with the APS and Spira systems were significantly correlated (r = 0·69; P<0·007), without systematic difference in the geometric means (P = 0·10). A moderate to good agreement was found for assessment of significant hyperresponsiveness. The results suggest that in dosimetric systems for bronchial challenge tests, the output of the nebulizer is dependent on the mode of nebulization, and this should be considered when standardizing the dose between devices and protocols. As long as the delivered dose is determined for the specified nebulization mode of the protocol, it may be possible to obtain comparable results between different devices.
近期关于支气管激发试验的技术建议旨在对导致第一秒用力呼气容积（FEV1）下降20%的激发剂量（PD20）进行标准化评估。本研究的目的是调查雾化方式对电脑化剂量仪（APS）输出量的影响，并比较两种不同剂量测定系统在体内获得的PD20。在持续雾化过程中，使用模拟呼吸对APS系统的输出量进行测试，以四种不同持续时间进行间歇启动。利用输出数据，对APS应用改良的乙酰甲胆碱激发方案，并与使用Spira剂量仪的标准设置进行比较，14名哮喘患者使用这两种系统进行重复的乙酰甲胆碱激发试验，间隔时间中位数（范围）为3（1 - 6）天。所有间歇模式设置下计算出的输出量（mg/min）均显著高于持续模式（P<0·001），且在间歇模式下，输出量取决于脉冲持续时间。用APS和Spira系统评估的PD20值显著相关（r = 0·69；P<0·007），几何平均数无系统差异（P = 0·10）。在评估显著高反应性方面发现了中度到良好的一致性。结果表明，在支气管激发试验的剂量测定系统中，雾化器的输出量取决于雾化方式，在对不同设备和方案的剂量进行标准化时应考虑这一点。只要针对方案中指定的雾化模式确定了输送剂量，不同设备之间可能会获得可比的结果。
