Walamies M A
Department of Clinical Physiology, North-Karelia Central Hospital, Joensuu, Finland.
Respir Med. 1998 Feb;92(2):173-7. doi: 10.1016/s0954-6111(98)90091-9.
Gas compression profile may aid in the diagnosis of airway obstruction. However, the behavior of this parameter in repeated tests and the deviations in patients with bronchial asthma have not been thoroughly described. Thirty-six health subjects aged 6-16 years were studied in two test sessions with a pressure/flow plethysmograph, and 57 asthmatic patients of similar age were studied once. Three volumes of compressed thoracic gas (Vcomp) were obtained: with 25%, 50% and 75% of vital capacity (VC) expired. Relative Vcomp was calculated using the actual amount of gas remaining in the lungs. Regarding the best and second best manoeuvre, coefficient of variation (CoV) in Vcomp ranged from 47 to 79% (controls) and from 48 to 112% (patients). Regarding the best manoeuvre in the first and second test session (controls), CoV in Vcomp ranged from 73 to 159%. Bronchodilator response had an extreme individual variation, and the changes were insignificant in both groups. In the paediatric population, the poor repeatability of Vcomp invalidates its use in clinical assessment of pulmonary function.
气体压缩曲线可能有助于诊断气道阻塞。然而，该参数在重复测试中的表现以及支气管哮喘患者中的偏差尚未得到充分描述。对36名6至16岁的健康受试者进行了两次压力/流量体积描记测试，对57名年龄相仿的哮喘患者进行了一次测试。获取了三个压缩胸内气体体积（Vcomp）：分别在呼出肺活量（VC）的25%、50%和75%时。相对Vcomp通过肺内剩余气体的实际量计算得出。对于最佳和次佳动作，Vcomp的变异系数（CoV）在对照组中为47%至79%，在患者组中为48%至112%。对于第一次和第二次测试中的最佳动作（对照组），Vcomp的CoV在73%至159%之间。支气管扩张剂反应存在极大的个体差异，两组的变化均不显著。在儿科人群中，Vcomp的重复性差使其无法用于肺功能的临床评估。
