[Thoracic hyperinflation and COPD. Beyond respiratory mechanics and dyspnea]. / Distension thoracique et BPCO, au-delà de la mécanique respiratoire et de la dyspnée.

ABSTRACT

INTRODUCTION: The interactions between thoracic hyperinflation and respiratory mechanics, as well as their importance in the development of dyspnoea, are now well understood. We discuss here other aspects of thoracic hyperinflation that are relevant in the context of COPD. BACKGROUND: Both clinical examination and imaging have a limited role in the detection of thoracic hyperinflation for which respiratory function tests remain the gold standard. Imaging, however, has led us to a better understanding of how the chest wall accommodates for hyperinflation, which mainly affects the diaphragm, particularly its vertical portion. More recently the adverse effects of hyperinflation on both pulmonary and systemic haemodynamics and life expectancy have been highlighted. VIEWPOINTS AND CONCLUSIONS: Thoracic hyperinflation affecting patients with COPD has important consequences that extend far beyond the framework of respiratory mechanics. In the future the importance of hyperinflation as a determinant of the prognosis should be confirmed and the most relevant parameter, in this context, defined. The potential links between thoracic hyperinflation and systemic inflammation should also be clarified.