AP-HP, Unité Fonctionnelle d'Explorations Fonctionnelles Respiratoires, Hôpital Armand-Trousseau, Paris, France.
Pediatr Pulmonol. 2012 Oct;47(10):987-93. doi: 10.1002/ppul.22526. Epub 2012 Feb 10.
In children unable to perform reliable spirometry, the interrupter resistance (R(int) ) technique for assessing respiratory resistance is easy to perform. However, few data are available on the possibility to use R(int) as a surrogate for spirometry. We aimed at comparing R(int) and spirometry at baseline and after bronchodilator administration in a large population of asthmatic children. We collected retrospectively R(int) and spirometry results measured in 695 children [median age 7.8 (range 4.8-13.9) years] referred to our lab for routine assessment of asthma disease. Correlations between R(int) and spirometry were studied using data expressed as z-scores. Receiver operator characteristic curves for the baseline R(int) value (z-score) and the bronchodilator effect (percentage predicted value and z-score) were generated to assess diagnostic performance. At baseline, the relationship between raw values of R(int) and FEV(1) was not linear. Despite a highly significant inverse correlation between R(int) and all of the spirometry indices (FEV(1) , FVC, FEV(1) /FVC, FEF(25-75%) ; P < 0.0001), R(int) could detect baseline obstruction (FEV(1) z-score ≤ -2) with only 42% sensitivity and 95% specificity. Post-bronchodilator changes in R(int) and FEV(1) were inversely correlated (rhô = -0.50, P < 0.0001), and R(int) (≥35% predicted value decrease) detected FEV(1) reversibility (>12% baseline increase) with 70% sensitivity and 69% specificity (AUC = 0.79). R(int) measurements fitted a one-compartment model that explained the relationship between flows and airway resistance. We found that R(int) had poor sensitivity to detect baseline obstruction, but fairly good sensitivity and specificity to detect reversibility. However, in order to implement asthma guidelines for children unable to produce reliable spirometry, bronchodilator response measured by R(int) should be systematically studied and further assessed in conjunction with clinical outcomes.
在无法进行可靠肺功能测定的儿童中，评估呼吸阻力的呼吸中断阻力（R(int)）技术易于操作。然而，关于 R(int) 是否可作为肺功能测定的替代指标，目前仅有少量数据。我们的目的是在大量哮喘儿童中比较 R(int)和支气管扩张剂给药前后的肺功能测定结果。我们回顾性地收集了在我们实验室因常规评估哮喘疾病而接受检查的 695 名儿童（中位年龄 7.8（4.8-13.9）岁）的 R(int)和肺功能测定结果。使用表示为 z 分数的数据研究 R(int)和肺功能测定之间的相关性。生成了 R(int)的基线值（z 分数）和支气管扩张剂效应（预测值百分比和 z 分数）的接收者操作特征曲线，以评估诊断性能。在基线时，R(int)的原始值与 FEV1 之间的关系不是线性的。尽管 R(int)与所有肺功能测定指标（FEV1、FVC、FEV1/FVC、FEF25-75%）之间呈高度显著的负相关（P < 0.0001），但 R(int)只能以 42%的灵敏度和 95%的特异性检测到基线阻塞（FEV1 z 分数≤-2）。R(int)和 FEV1 的支气管扩张剂后变化呈负相关（rhô=-0.50，P < 0.0001），R(int)（预测值下降≥35%）检测到 FEV1 的可逆转性（基线增加≥12%），灵敏度为 70%，特异性为 69%（AUC=0.79）。R(int)的测量结果拟合了一个单室模型，该模型解释了流量和气道阻力之间的关系。我们发现，R(int)检测基线阻塞的灵敏度较差，但检测可逆转性的灵敏度和特异性较好。然而，为了为无法进行可靠肺功能测定的儿童实施哮喘指南，应该系统地研究并结合临床结果进一步评估 R(int)测量的支气管扩张剂反应。
