RESUMO
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.
Assuntos
Broncodilatadores/farmacologia , Medidas de Volume Pulmonar , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Mecânica Respiratória/efeitos dos fármacos , Administração por Inalação , Idoso , Resistência das Vias Respiratórias , Broncodilatadores/uso terapêutico , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Estudos Retrospectivos , Capacidade VitalRESUMO
Although FEV, 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 FEV, 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 (FEV,/FVC < 70%). BD response was defined for FEV, and FVC as per ATS guidelines and for other LV as o>_10% of baseline (4>_5 and >_15% were also analyzed). FEV, 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 FEV, and FVC. Plethismography added 9% more. The magnitude of volume responses correlated with the degree of baseline yperinflation. Percentages of responders varied greatly using different thresholds (A>5 and >_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 bronchodilato rs identified by changes in lung volumes but not detected by an improvement in FEV, The selection of LV response criteria has important influence on the magnitude of this additional detectìon.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Broncodilatadores , Medidas de Volume Pulmonar , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Mecânica Respiratória , Administração por Inalação , Resistência das Vias Respiratórias , Broncodilatadores , Volume Expiratório Forçado , Estudos Retrospectivos , Capacidade VitalRESUMO
Although FEV, 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 FEV, 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 (FEV,/FVC < 70%). BD response was defined for FEV, and FVC as per ATS guidelines and for other LV as o>_10% of baseline (4>_5 and >_15% were also analyzed). FEV, 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 FEV, and FVC. Plethismography added 9% more. The magnitude of volume responses correlated with the degree of baseline yperinflation. Percentages of responders varied greatly using different thresholds (A>5 and >_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 bronchodilato rs identified by changes in lung volumes but not detected by an improvement in FEV, The selection of LV response criteria has important influence on the magnitude of this additional detectýon.(AU)
Assuntos
Estudo Comparativo , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Broncodilatadores/farmacologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Medidas de Volume Pulmonar , Mecânica Respiratória/efeitos dos fármacos , Broncodilatadores/uso terapêutico , Volume Expiratório Forçado , Resistência das Vias Respiratórias , Administração por Inalação , Estudos Retrospectivos , Capacidade VitalRESUMO
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.
