Nasal high flow versus Non-invasive ventilation in patients with acute exacerbation of chronic obstructive pulmonary disease

Introduction: Non-invasive ventilation (NIV) use in chronic obstructive pulmonary disease (COPD) exacerbation has increased significantly, however, approximately 1/3 of patients have either contraindications or cannot tolerate NIV therapy. Recently, nasal high flow (NHF) oxygen therapy has been introduced for the management of hypoxemic respiratory failure with positive physiological effects on respiratory support. These effects have also been observed in stable COPD patients with or without chronic hypercapnia. However, the use of NHF during acute COPD exacerbations (AECOPD) is still questionable with limited studies showing favourable outcomes. Objective: To evaluate NHF compared to NIV in patients with AECOPD and acute or acute on chronic hypercapnic respiratory failure. Method: A randomized controlled trial (RCT) in patients presenting with AECOPD (defined by pH >7.25 <7.35, PaCO2>45mmHg) and are clinically indicated for NIV therapy (pH<7.35, PaCO2>45mmHg, RR>23). Primary end point is treatment failure, secondary end points include, changes in respiratory variables, patient comfort and presence of pulmonary and extra-pulmonary complications. Results: So far, 27/498 participants have been enrolled. Mean age 74 (+/- 16) years. Seventy-eight percent were male. Prior to randomisation 9/27 (33.3%) had a pH between 7.30-7.35 and 18/27 (66.6%) had a pH between 7.25-7.29. Twelve patients (44%) were randomised to NIV and 15 (56%) to NHF. To date, treatment failure in the NIV cohort is 16% and 27% in the NHF cohort. Conclusions: These are preliminary data of a large RCT. Further and more detailed analysis will be presented at the Congress.