Bronchoscopic treatments of chronic obstructive pulmonary disease (COPD): a narrative review

Background and Objective: Several procedural therapies have been described for patients with advanced chronic obstructive pulmonary disease (COPD) to date. The primary objective of this narrative review is to critically evaluate the effectiveness, safety, and long-term outcomes of these bronchoscopic and surgical interventions. Methods: The databases that were mainly used to search relevant studies were Google Scholar, PubMed, EMBASE and Cochrane library from January 1950 to April 2023. Articles written in English language are included only. Key Content and Findings: Lung volume reduction (LVR) surgery represents one of the first successful invasive options in patients with advanced heterogenous emphysema. This landmark surgical option demonstrated improvement in health status and lung function outcomes, but at the cost of significant morbidity and mortality. Various endobronchial procedures have been developed, one of which is endobronchial valves (EBV) placement for bronchoscopic LVR that have been extensively studied and have a potential to offer comparable outcomes with lower mortality and complication rates compared to surgical LVR. Several multicenter trials and studies have shown significant improvements in lung function, exercise capacity, and quality of life (QOL) with the use of EBV in patients with emphysema, although adverse events such as pneumothorax and pneumonia have been observed. Data regarding other modalities is evolving. For patients with chronic bronchitis, bronchial rheoplasty has shown significant improvements in QOL, reduced cough and phlegm production, and a decrease in goblet cell hyperplasia. Another procedure, metered cryospray, has demonstrated initial improvements in symptoms, but long-term efficacy is unproven. Clinical trials are underway to further evaluate its effectiveness. Lastly, for patients with frequent COPD exacerbations, targeted lung denervation has shown preliminary safety and efficacy in reducing respiratory events and COPD exacerbations. Ongoing clinical trials are underway that focus on the frequent exacerbation phenotype. Conclusions: LVR surgery is deemed effective in carefully selected patients with severe emphysema but is associated with higher surgical risk and morbidity and mortality. Bronchoscopic interventions, particularly EBV, offers an attractive, comparatively lower risk, option for a greater group of patients with severe emphysema to achieve significant improvements in 6-minute walk distance, QOL, and pulmonary function tests.