TY - JOUR T1 - COPD beyond proximal bronchial obstruction: phenotyping and related tools at the bedside JF - European Respiratory Review JO - EUROPEAN RESPIRATORY REVIEW DO - 10.1183/16000617.0010-2019 VL - 28 IS - 152 SP - 190010 AU - Thibaut Capron AU - Arnaud Bourdin AU - Thierry Perez AU - Pascal Chanez Y1 - 2019/06/30 UR - http://err.ersjournals.com/content/28/152/190010.abstract N2 - Chronic obstructive pulmonary disease (COPD) is characterised by nonreversible proximal bronchial obstruction leading to major respiratory disability. However, patient phenotypes better capture the heterogeneously reported complaints and symptoms of COPD. Recent studies provided evidence that classical bronchial obstruction does not properly reflect respiratory disability, and symptoms now form the new paradigm for assessment of disease severity and guidance of therapeutic strategies. The aim of this review was to explore pathways addressing COPD pathogenesis beyond proximal bronchial obstruction and to highlight innovative and promising tools for phenotyping and bedside assessment. Distal small airways imaging allows quantitative characterisation of emphysema and functional air trapping. Micro-computed tomography and parametric response mapping suggest small airways disease precedes emphysema destruction. Small airways can be assessed functionally using nitrogen washout, probing ventilation at conductive or acinar levels, and forced oscillation technique. These tests may better correlate with respiratory symptoms and may well capture bronchodilation effects beyond proximal obstruction.Knowledge of inflammation-based processes has not provided well-identified targets so far, and eosinophils probably play a minor role. Adaptative immunity or specific small airways secretory protein may provide new therapeutic targets. Pulmonary vasculature is involved in emphysema through capillary loss, microvascular lesions or hypoxia-induced remodelling, thereby impacting respiratory disability.COPD bronchial obstruction poorly reflects respiratory disability; this review addresses pathways for pathogenesis beyond proximal obstruction through small airways imaging and function, inflammation processes and pulmonary vascular involvement. bit.ly/30JlKVi ER -