Efeitos aditivos da ventilação não invasiva ao treinamento muscular respiratório sobre a tolerância ao exercício na DPOC: ensaio clínico cego, randomizado e controlado

Abstract

Exercise intolerance in COPD patients, is one of the causative factors of reduction in quality of life due to physical deconditioning, appears to be the result of interaction between the overload of the respiratory system and respiratory muscle weakness, associated with decreased peripheral muscle strength. The aim of this study was to evaluate the additive effects of non-invasive ventilation to the inspiratory muscle training on exercise tolerance in COPD patients. The study included 9 patients with COPD, 6 males, who underwent evaluation of pulmonary function, cardiopulmonary exercise test on a cycle ergometer and constant-work load test associated to the use of non-invasive ventilation with CPAP and PAV modes before and after a high intensity inspiratory muscle training program and quality of life assessment. A statistically significant increase was observed in the inspiratory and expiratory muscle strength (p<0.0001) and exercise’s tolerance time associated with non-invasive ventilation modes CPAP and PAV (p=0,02). The combination of non-invasive ventilation and inspiratory muscle training had beneficial results at improvement in exercise tolerance for all patients with clinically relevant value in PAV mode (TLim=210s), which is twice of the minimum clinically important difference value for a cycle ergometer test. As well as the use of the same mode decreases the drop in oxygen saturation of patients in the exercise. The findings show that the association between non-invasive ventilation, especially PAV mode, and respiratory muscle training promote beneficial effects on exercise tolerance, tissue oxygenation, perceived exertion of the lower limbs and sensation of dyspnea during exercise.