- 期刊
Values of Static Lung Volume Measurements in the Assessment of Bronchodilator Responses in COPD
靜態肺容積測量於評估慢性阻塞性肺病支管擴張試驗的價值
摘要
Background: The bronchodilator test (BDT) is essential in the diagnosis and severity staging of chronic obstructive pulmonary disease (COPD). Of late, the assessment of improvement in lung hyperinflation has been emphasized. The purpose of this study was to evaluate the values of static lung volume (SLV) measurements in the assessment of BDT in COPD. Methods: Seventy patients with COPD were investigated. Static lung volumes were measured by the helium dilution method. Positive BDT response was defined as forced expiratory volume in 1 second (FEV1) according to the American Thoracic Society (ATS) guideline, and for any SLV as changes 12% of baseline and 200 ml. Results: The baseline FEV1 residual volume (RV), total lung capacity (TLC) and inspiratory capacity (IC), were 56±17% (mean±SD), 169±60%, 120±25% and 127±32% of predicted, respectively. Mean changes after BDT were 12% for FEV1 (p＜0.0001), 9% for FVC (p＜0.0001), 10% for IC (p＜0.0001), -5% for RV (p=0.0004) and 0.1% for TLC (p=0.5). Changes in IC strongly correlated with changes in FEV1 and FRC (p＜0.001). Measurement of FEV1 identified 23 (33%) patients as responders. A greater proportion of responders were uncovered by measurement of IC (40%) than of RV (19%) (p=0.005) or of TLC (1.4%) (p＜0.0001). Changes in SLV5 identified 24% (17/70) more patients as responders in addition to those in FEV1 (23/70), with changes in IC covering the majority (14/17). Conclusion: These data suggest that a remarkable proportion of COPD patients who have significant volume responses during BDT was not identified by measuring FEV1, based on the current ATS criteria. In addition, IC is the most appropriate parameter in the assessment of bronchodilator responsiveness in such patients.
並列摘要
Background: The bronchodilator test (BDT) is essential in the diagnosis and severity staging of chronic obstructive pulmonary disease (COPD). Of late, the assessment of improvement in lung hyperinflation has been emphasized. The purpose of this study was to evaluate the values of static lung volume (SLV) measurements in the assessment of BDT in COPD. Methods: Seventy patients with COPD were investigated. Static lung volumes were measured by the helium dilution method. Positive BDT response was defined as forced expiratory volume in 1 second (FEV1) according to the American Thoracic Society (ATS) guideline, and for any SLV as changes 12% of baseline and 200 ml. Results: The baseline FEV1 residual volume (RV), total lung capacity (TLC) and inspiratory capacity (IC), were 56±17% (mean±SD), 169±60%, 120±25% and 127±32% of predicted, respectively. Mean changes after BDT were 12% for FEV1 (p＜0.0001), 9% for FVC (p＜0.0001), 10% for IC (p＜0.0001), -5% for RV (p=0.0004) and 0.1% for TLC (p=0.5). Changes in IC strongly correlated with changes in FEV1 and FRC (p＜0.001). Measurement of FEV1 identified 23 (33%) patients as responders. A greater proportion of responders were uncovered by measurement of IC (40%) than of RV (19%) (p=0.005) or of TLC (1.4%) (p＜0.0001). Changes in SLV5 identified 24% (17/70) more patients as responders in addition to those in FEV1 (23/70), with changes in IC covering the majority (14/17). Conclusion: These data suggest that a remarkable proportion of COPD patients who have significant volume responses during BDT was not identified by measuring FEV1, based on the current ATS criteria. In addition, IC is the most appropriate parameter in the assessment of bronchodilator responsiveness in such patients.