[Changes in ventilatory mechanics in emphysema].

The increased airway resistance and hyperinflation characteristic of chronic obstructive pulmonary disease (COPD) affect respiratory muscle function, particularly that of the diaphragm. The compensatory changes of the breathing pattern due to expiratory flow limitation lead to a further increase of the mechanical load on the ventilatory muscles during forced ventilation. Therapeutic strategies which reduce hyperinflation and the increased airway obstruction, improve the neuromechanical efficiency of the inspiratory muscles.