抽象的
比较从最大或部分肺部通胀开始的强制呼气式动作期间在口腔中测量的同种型流动是评估深入吸入对气道口径的影响的手段。本研究的目的是研究对诱导的支气管混凝脉中深入吸入的影响是否受到肺部体积的影响,其中肺部体积和由于胸部气体压缩而导致的胸气压缩,在迫使呼气的机动过程中发生。四种健康受试者和六种具有轻度至中度哮喘受试者的六个受试者在控制和甲素(MCH)吸入攻击期间进行了局部和最大的强制呼气的举射的呼气管。口腔流动(V1)绘制到过期的体积(VMO)和通过体积描记法(VPL)的同时胸体积(分别分别测量V1-VMO环路和V1-VPL环)。通过测定1)在V1-VMO环路(M / PMO)上的30,40和50%的对照中的分配到50%和50%的呼气流量(M / P)的最大呼气流量(M / P)的效果来定量深入吸入的影响和V1-VPL循环(M / PPL)在控制和MCH端点处;2)在整个挑战上,在V1-VMO环路(MPST,MO)和V1-VPL循环(MPSL,PL)上的30,40和50%的控制FVC的线性消退的斜率在30,40和50%的控制FVC上,在整个挑战中。在对照中,M / PMO和M / PPL是相似的。在MCH端点,M / PMO和M / PPL增加超过双重(P <0.002),始终超过M / PPL(P <0.001)。另外,M / PMO和M / PPL两者都与肺体积相同(P <0.001)。 By contrast, MPsl,mo and MPsl,pl were not significantly different from each other (p = 0.8), and were also similar at the different lung volumes (p = 0.6). We conclude that during induced bronchoconstriction, the bronchodilation following a deep inhalation, expressed as maximal to partial flow ratio is dependent both on lung volume and volume differences due to thoracic gas compression. The use of expired flow and volume measurements may lead to a small but systematic overestimation of the bronchodilator effect of a deep inhalation. On the contrary, maximal to partial flow slope is insensitive either to lung volume or volume differences due to thoracic gas compression and can, therefore, be fairly determined from expired flow-volume loops.