The Role of High Flow Nasal Cannula in COVID-19 Associated Pneumomediastinum and Pneumothorax

Background: Pneumomediastinum, subcutaneous emphysema and pneumothorax are not rarely observed during the COVID-19 pandemic. Such complications can worsen gas exchange and the overall prognosis in critical patients. The aim of this study is to investigate what predisposing factors are related to pneumomediastinum and pneumothorax in SARS-CoV2-Acute Respiratory Distress Syndrome (ARDS), what symptoms may predict a severe and potentially fatal complication and what therapeutical approach may provide a better outcome. Methods: In this single center cohort study, we recorded data from 45 critically ill COVID-19 patients who developed one or more complicating events among pneumomediastinum, subcutaneous emphysema and pneumothorax. All patients showed ARDS and underwent non-invasive ventilation (NIV) at baseline. Patients with mild to moderate ARDS and pneumomediastinum/pneumothorax (n = 25) received High Flow Nasal Cannula (HFNC), while patients with severe ARDS and pneumomediastinum/pneumothorax underwent HFNC (n = 10) or invasive mechanical ventilation (IMV) (n = 10). Results: Pneumomediastinum/pneumothorax developed in 10.5% of subjects affected by SARS-coV2-ARDS. Dyspnea affected 40% and cough affected 37% of subjects. High resolution computed tomography of the chest showed bilateral diffuse ground glass opacities (GGO) in 100% of subjects. Traction bronchiolectasis, reticulation, crazy paving and distortion were observed in 64%. Furthermore, 36% showed subcutaneous emphysema. Non-severe ARDS cases received HFNC, and 76% patients recovered from pneumomediastinum/pneumothorax over a median follow up of 5 days. Among severe ARDS cases the recovery rate of pneumomediastinum/pneumothorax was 70% with the HFNC approach, and 10% with IMV. Conclusion: HFNC is a safe and effective ventilatory approach for critical COVID-19 and has a positive role in associated complications such as pneumomediastinum and pneumothorax.