Figueroa-Casas Juan B, Diez Ana R, Rondelli María P, Figueroa-Casas Marcelo P, Figueroa-Casas Juan C
Departmento Medicina Respiratoria, Instituto Cardiovascular de Rosario.
Medicina (B Aires). 2003;63(5):377-82.
Although FEV1 improvement is routinely used to define bronchodilator (BD) response, it correlates poorly with clinical effects. Changes in lung volumes (LV) have shown better correlation with exercise tolerance and might be more sensitive to detect BD effects. We assessed the additional contribution of measuring LV before and after BD to detect acute improvement in lung function not demonstrated by FEV1, and the influence of the response criteria selected on this contribution. We analyzed 98 spirometries and plethismographies performed pre and post BD in patients with airflow obstruction (FEV1/FVC < 70%). BD response was defined for FEV1 and FVC as per ATS guidelines and for other LV as delta > or = 10% of baseline (delta > or = 5 and > or = 15% were also analyzed). FEV1 identified as responders 32% of patients. Greater proportions were uncovered by slow vital capacity (51%, p < 0.001), inspiratory capacity (43%, p < 0.05) and residual volume (54%, p < 0.001). Slow spirometry identified 11% of responders additional to those detected by FEV1 and FVC. Plethismography added 9% more. The magnitude of volume responses correlated with the degree of baseline hyperinflation. Percentages of responders varied greatly using different thresholds (delta > or = 5 and > or = 15%). Mean change and proportions of responders for each LV varied significantly (p < 0.05) whether change was expressed as percent of baseline or predicted values. A considerable proportion of patients with airflow obstruction shows acute response to bronchodilators identified by changes in lung volumes but not detected by an improvement in FEV1. The selection of LV response criteria has important influence on the magnitude of this additional detection.
尽管第一秒用力呼气容积（FEV1）的改善常被用于定义支气管扩张剂（BD）反应，但它与临床效果的相关性较差。肺容积（LV）的变化与运动耐量显示出更好的相关性，并且可能对检测BD效果更敏感。我们评估了在BD前后测量LV对检测FEV1未显示的肺功能急性改善的额外贡献，以及所选反应标准对这一贡献的影响。我们分析了98例气流受限（FEV1/FVC<70%）患者在BD前后进行的肺量计和体积描记法检查。根据美国胸科学会（ATS）指南定义FEV1和用力肺活量（FVC）的BD反应，对于其他LV，定义为变化量≥基线的10%（也分析了变化量≥5%和≥15%的情况）。FEV1将32%的患者识别为反应者。慢肺活量（51%，p<0.001）、吸气量（43%，p<0.05）和残气量（54%，p<0.001）识别出的患者比例更高。慢肺活量检查识别出的反应者比FEV1和FVC检测出的多11%。体积描记法又增加了9%。容积反应的幅度与基线肺过度充气程度相关。使用不同阈值（变化量≥5%和≥15%）时，反应者的百分比差异很大。无论变化是以基线值还是预测值的百分比表示，每个LV的平均变化和反应者比例均有显著差异（p<0.05）。相当一部分气流受限患者对支气管扩张剂有急性反应，这种反应通过肺容积变化得以识别，但未被FEV1的改善所检测到。LV反应标准的选择对这种额外检测的幅度有重要影响。
