Bronchoscopic Lung Volume Reduction

Emphysema is a form of the chronic obstructive pulmonary disease characterized by destruction of alveolar tissue, abnormal and permanent enlargement of the airspaces distal to the terminal bronchioles. The physiologic consequences of the anatomical changes include loss of elastic recoil, early airway closure during exhalation, and air trapping in the distal air spaces. Alveolar wall destruction with the formation of emphysematous blebs and bullae leads to increased physiologic dead space and loss of gas exchanging surface. Further, air trapping and hyperinflation press the diaphragm into a flat configuration and place all the muscles of respiration at a mechanical overstretch disadvantage. In combination, these mechanisms lead to refractory dyspnea in affected individuals. Lung volume reduction surgery (LVRS) is a surgical treatment for patients with advanced emphysema whose dyspnea is poorly controlled with the usual therapies. LVRS entails reducing the lung volume by wedge excisions of emphysematous tissue. However, surgical morbidity is high, and non-pulmonary comorbidities may preclude surgery. Minimally invasive techniques have been created, and provide similar benefits to surgical outcomes with significantly less morbidity and mortality. Bronchoscopic Lung Volume Reduction (BLVR) refers to techniques developed to treat hyperinflation due to emphysema, using devices deployed via a flexible bronchoscope. The devices and techniques for BLVR will be reviewed in this manuscript.

Keywords: Airway Bypass, Coils, COPD, Emphysema, Endobronchial Valve, Hydrogel, Lung Volume Reduction, Thermal Ablation.