Evidence on Non-Invasive Respiratory Support During Flexible Bronchoscopy: A Narrative Review.

Background: Flexible bronchoscopy (FB) is a widely used diagnostic and therapeutic procedure in patients with pulmonary disease, many of whom are at risk of gas exchange impairment. FB may exacerbate hypoxaemia due to increased airway resistance, alveolar derecruitment, and haemodynamic fluctuations. Objectives: To assess the effectiveness of non-invasive respiratory support strategies in preventing oxygen desaturation and respiratory complications during FB. Methods: A systematic review and meta-analysis were conducted using PubMed and Cochrane databases, covering studies from 2000 to 2024. Inclusion criteria focused on adult patients undergoing FB with any form of non-invasive oxygen support. Twelve high-quality studies were selected, including randomised trials and prospective cohorts. Results: High-flow therapy (HFT) was more effective than conventional oxygen therapy (COT) in maintaining oxygenation and reducing procedure interruptions, especially in patients with moderate hypoxaemia or risk factors such as obesity and obstructive sleep apnoea. Continuous positive airway pressure (CPAP) and non-invasive ventilation (NIV) offered superior oxygenation and ventilatory support in patients with more severe respiratory or cardiac compromise. Conclusions: Non-invasive respiratory support should be individualised based on patient risk and procedural complexity. HFT benefits mild-to-moderate cases, while CPAP or NIV is preferable in more severe conditions. Further multicentre randomised trials are needed to establish formal guidelines.