[Diaphragm dysfunction in patients with chronic obstructive pulmonary disease].

Chronic obstructive pulmonary disease (COPD) is characterised by alterations in the airways and lung parenchyma resulting in an increased respiratory workload. Besides an increased load and hyperinflation of the thorax, additional factors, such as systemic inflammation, oxidative stress, hypoxia and loss of muscle mass, further have a negative influence on diaphragm contractility. The diaphragm seems to adapt only partly to the altered circumstances to which it is exposed. As a consequence, several morphological, biochemical and functional alterations occur in the diaphragm, resulting in diaphragm dysfunction. In an appropriately selected group of patients, the function of the diaphragm can be improved by respiratory muscle training, oral nutritional therapy or hormonal interventions.