DIAPHRAGMATIC MOBILITY, LUNG HYPERINFLATION AND EFFECTS OF THE PULMONARY REHABILITATION

Rationale: The diaphragm pathophysiological changes occurring in chronic obstructive pulmonary disease (COPD) leads to functional inefficiency that strongly correlates to the loss of lung function. Muscle fiber shortening follows lung hyperinflation, resulting to a chronic mechanical disadvantage, which worsens in COPD exacerbations. The diaphragmatic mobility (DM) is mostly assessed with techniques that exposes the patient to risks. The ultrasonography on M-mode is easy to use, safe and measures directly the diaphragmatic dome displacement. Goals: to determine whether the COPD impairs the DM, and verify improvements after an inpatient pulmonary rehabilitation (PR). Methods: ultrasonography on M-mode assessed the rest breathing and the slow deep inspiration on 52 patients and 15 healthy controls. Lung functions test, arterial blood gas analyses, six minute walk test were also performed. Results: after initial screening, 36 COPD patients ended the PR. The DM was lower on the slow deep inspiration on COPD patients and correlated with the COPD severity (r=0.8, p<0.001). The DM on rest breathing was higher for COPD patients and also correlated to the lung disease severity (r=0.74, p<0.001). After the PR the DM on the slow deep inspiration increases from 4.58cm±1.83cm to 5.45cm±1.56cm (p<0.01). Conclusions: ultrasonography on M-mode showed the correlation between DM impairment and COPD severity. The PR improves diaphragmatic function.