RESUMO
OBJECTIVE: Pulmonary rehabilitation (PR) improves exercise capacity in most but not all COPD patients. The factors associated with treatment success and the role of chest wall mechanics remain unclear. We investigated the impact of PR on exercise performance in COPD with severe hyperinflation. METHODS: We evaluated 22 COPD patients (age, 66 ± 7 years; FEV1 = 37.1 ± 11.8% of predicted) who underwent eight weeks of aerobic exercise and strength training. Before and after PR, each patient also performed a six-minute walk test and an incremental cycle ergometer test. During the latter, we measured chest wall volumes (total and compartmental, by optoelectronic plethysmography) and determined maximal workloads. RESULTS: We observed significant differences between the pre- and post-PR means for six-minute walk distance (305 ± 78 vs. 330 ± 96 m, p < 0.001) and maximal workload (33 ± 21 vs. 39 ± 20 W; p = 0.02). At equivalent workload settings, PR led to lower oxygen consumption, carbon dioxide production (VCO2), and minute ventilation. The inspiratory (operating) rib cage volume decreased significantly after PR. There were 6 patients in whom PR did not increase the maximal workload. After PR, those patients showed no significant decrease in VCO2 during exercise, had higher end-expiratory chest wall volumes with a more rapid shallow breathing pattern, and continued to experience symptomatic leg fatigue. CONCLUSIONS: In severe COPD, PR appears to improve oxygen consumption and reduce VCO2, with a commensurate decrease in respiratory drive, changes reflected in the operating chest wall volumes. Patients with severe post-exercise hyperinflation and leg fatigue might be unable to improve their maximal performance despite completing a PR program.
Assuntos
Terapia por Exercício/métodos , Exercício Físico/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Idoso , Dióxido de Carbono/metabolismo , Teste de Esforço , Feminino , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Valores de Referência , Testes de Função Respiratória , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Análise e Desempenho de Tarefas , Parede Torácica/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Caminhada/fisiologiaRESUMO
Objective: Pulmonary rehabilitation (PR) improves exercise capacity in most but not all COPD patients. The factors associated with treatment success and the role of chest wall mechanics remain unclear. We investigated the impact of PR on exercise performance in COPD with severe hyperinflation. Methods: We evaluated 22 COPD patients (age, 66 ± 7 years; FEV1 = 37.1 ± 11.8% of predicted) who underwent eight weeks of aerobic exercise and strength training. Before and after PR, each patient also performed a six-minute walk test and an incremental cycle ergometer test. During the latter, we measured chest wall volumes (total and compartmental, by optoelectronic plethysmography) and determined maximal workloads. Results: We observed significant differences between the pre- and post-PR means for six-minute walk distance (305 ± 78 vs. 330 ± 96 m, p < 0.001) and maximal workload (33 ± 21 vs. 39 ± 20 W; p = 0.02). At equivalent workload settings, PR led to lower oxygen consumption, carbon dioxide production (VCO2), and minute ventilation. The inspiratory (operating) rib cage volume decreased significantly after PR. There were 6 patients in whom PR did not increase the maximal workload. After PR, those patients showed no significant decrease in VCO2 during exercise, had higher end-expiratory chest wall volumes with a more rapid shallow breathing pattern, and continued to experience symptomatic leg fatigue. Conclusions: In severe COPD, PR appears to improve oxygen consumption and reduce VCO2, with a commensurate decrease in respiratory drive, changes reflected in the operating chest wall volumes. Patients with severe post-exercise hyperinflation and leg fatigue might be unable to improve their maximal performance despite completing a PR program.
Objetivo: A reabilitação pulmonar (RP) melhora a capacidade de exercício na maioria (mas não todos) dos pacientes com DPOC. Os fatores associados ao sucesso do tratamento e o papel da mecânica da parede torácica na determinação desse sucesso ainda não é claro. Investigamos o impacto da RP no desempenho ao exercício em pacientes com DPOC e hiperinsuflação grave. Métodos: Foram avaliados 22 pacientes com DPOC (idade, 66 ± 7 anos; VEF1 = 37,1 ± 11,8% do previsto) submetidos a oito semanas de exercícios aeróbicos e treino de força. Antes e depois da RP, cada paciente também realizou um teste de caminhada de seis minutos e um teste de exercício incremental em uma bicicleta ergométrica. Durante esse último, os volumes da parede torácica (total e compartimental por pletismografia optoeletrônica) e a carga de trabalho máxima foram determinados. Resultados: Diferenças significativas foram observadas entre as médias pré e pós-RP da distância percorrida no teste de caminhada de seis minutos (305 ± 78 vs. 330 ± 96 m; p < 0,001) e da carga máxima (33 ± 21 vs. 39 ± 20 W; p = 0,02). Sob parâmetros de carga de trabalho equivalente, a RP levou a valores menores de consumo de oxigênio, produção de dióxido de carbono (VCO2) e ventilação minuto. O volume inspiratório (operacional) da caixa torácica diminuiu significativamente após a RP. Em 6 pacientes, a RP não aumentou a carga máxima. Após a RP, esses pacientes não apresentaram uma diminuição significativa na VCO2 durante o exercício, tiveram maiores volumes expiratórios finais da parede torácica com padrão respiratório mais rápido e superficial e continuaram a apresentar fadiga sintomática nas pernas. Conclusões: Na DPOC grave, a RP parece melhorar o consumo de oxigênio e reduzir VCO2, com uma diminuição proporcional no drive respiratório, mudanças essas que são refletidas nos volumes operacionais da parede torácica. Pacientes com hiperinsuflação grave pós-exercício e fadiga nas pernas podem ser incapazes de melhorar seu desempenho máximo apesar de completarem um programa de RP.
Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/reabilitação , Dióxido de Carbono/metabolismo , Teste de Esforço , Pulmão/fisiopatologia , Consumo de Oxigênio , Valores de Referência , Testes de Função Respiratória , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Análise e Desempenho de Tarefas , Parede Torácica/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Caminhada/fisiologiaRESUMO
Rationale: Exacerbations are key drivers of morbidity and mortality in chronicobstructive pulmonary disease (COPD).Objectives: We compared the relative efficacy of the long-acting inhaledbronchodilator/anti-inflammatory combination (salmeterol/fluticasone propionate) 50/500mcg bd and the long-acting bronchodilator (tiotropium) 18mcg od in preventing exacerbations and related outcomes in moderate severe COPD Methods: 1323 patients (mean age 64yr, forced expiratory volume in 1sec 39 per cent predicted) were randomized in 2-year, double blind, double-dummy, parallel study.Measurements and Main Results: Primary endpoint was healthcare utilization exacerbation rate. Other endpoints included health status measured by St. Georges Respiratory Questionnaire (SGRQ), mortality, adverse events and study withdrawal.Probability of withdrawing from the study was 29 per cent greater with tiotropium than salmeterol/fluticasone propionate (p=0.005). The modelled annual exacerbation rate was 1.28 in the salmeterol/fluticasone propionate group and 1.32 in the tiotropium group (rate ratio 0.967 [95 per cent CI: 0.836 to 1.119]; p=0.656). The SGRQ total score was statistically significantly lower at 2 years on salmeterol/fluticasone propionateversus tiotropium (difference 2.1 units, 95 per cent CI: 0.1 to 4.0, p=0.038). Mortality was significantly lower in the salmeterol/fluticasone propionate group; 21 (3 per cent of patients in this group died compared to 38 (6 per cent) in the tiotropium group (p=0.032). Morepneumonias were reported in the salmeterol/fluticasone propionate group relative to tiotropium (p=0.008).Conclusions: We found no difference in exacerbation rate between salmeterol/fluticasone propionate and tiotropium. More patients failed to complete the study receiving tiotropium. A small statistically significant beneficial effect was found on health status, with an unexpected finding of lower deaths in salmeterol/fluticasone propionate treated patients.
Assuntos
Humanos , Doença Pulmonar Obstrutiva Crônica , Mortalidade , Nível de SaúdeRESUMO
Bronchodilators, including long-acting beta(2)-adrenoceptor agonists and anticholinergic bronchodilators, are effective in the treatment of chronic obstructive pulmonary disease. Evidence suggests that the addition of a long-acting beta(2)-agonist to an inhaled corticosteroid is associated with a reduced rate of exacerbations compared with either treatment alone or placebo. However, it is not known whether a long-acting beta(2)-agonist/inhaled corticosteroid combination is more effective than an anticholinergic bronchodilator alone in reducing exacerbations. The Investigating New Standards for Prophylaxis In Reduction of Exacerbations (INSPIRE) trial will study salmeterol (a long-acting beta(2)-agonist) in combination with fluticasone propionate (an inhaled corticosteroid) compared with tiotropium bromide (an anticholinergic bronchodilator) in patients with moderate-to-severe chronic obstructive pulmonary disease. The INSPIRE study is a multicentre, randomised, double-blind, double dummy, parallel group study conducted over 104 weeks. This is the first study to use two parallel definitions of an exacerbation; an event-based exacerbation is defined as one that requires use of healthcare resources, including additional treatment and hospitalization, whereas a symptom-based exacerbation is defined as one that satisfies the 1987 Anthonisen criteria. It is also the first study to compare the long-term effects of salmeterol/fluticasone propionate with tiotropium bromide on the rate of event-based exacerbations. Endpoints include rate of exacerbations (primary endpoint), time to first exacerbation, and duration of exacerbations. Health outcomes will be assessed via the St George's Respiratory Questionnaire. If the innovative methodology of utilizing 2 definitions of exacerbation proves successful, it will set the benchmark for future studies in chronic obstructive pulmonary disease.
Assuntos
Albuterol/análogos & derivados , Androstadienos/uso terapêutico , Broncodilatadores/uso terapêutico , Antagonistas Colinérgicos/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuterol/uso terapêutico , Fluticasona , Humanos , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Xinafoato de Salmeterol , Brometo de TiotrópioRESUMO
Both oxygen therapy and bronchodilators reduce exertional breathlessness and improve exercise tolerance in patients with stable chronic obstructive pulmonary disease (COPD). However their relative effectiveness and the value of their combined use on exercise performance has not been assessed. The effects of 5 mg of salbutamol plus 500 microg ipratropium bromide nebulisation followed by a 6-min walking test while breathing O(2) were studied in a randomised, single-blind, placebo controlled, crossover trial in 28 patients with severe or very severe COPD, breathless on exertion and with oxygen saturation < or = 89% at rest or on exercise. Bronchodilator reversibility was minimal. The 6-min walking distance increased from 356 (128)m to 377 (117)m after the bronchodilator (P<0.05), to 406 (109)m after supplementary oxygen but without bronchodilators (P 0.011 versus bronchodilators/air and 0.001 versus placebo/air), and to 430 (109)m after the combination of oxygen and the bronchodilators (P<0.0001 versus placebo/air and bronchodilators/air; P=0.014 versus placebo/oxygen). End-exercise dyspnea only fell significantly when oxygen and bronchodilator were combined. In severe or very severe COPD patients with relatively fixed airway obstruction bronchodilators enhance exercise performance obtained with oxygen. Clinically relevant improvement is possible when therapies with a different mechanism of action are combined.