Efficiency of neural respiratory drive changes during non-invasive ventilation and high-flow nasal cannula oxygen therapy in AECOPD patients with acute hypercapnic respiratory failure: A randomised cross-over study

Background: Non-invasive ventilation (NIV) is recommended as the first-line treatment for patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) complicated by decompensated hypercapnic acute respiratory failure (ARF). High-flow nasal cannula oxygen therapy (HFNO), given its superior tolerance and patient adherence, has emerged as a promising alternative non-invasive respiratory support modality applicable across a wider range of clinical scenarios. This study aimed to investigate the neurophysiological effects of NIV and HFNO in AECOPD patients with hypercapnic ARF. Methods: A prospective, randomised, crossover trial involving 10 AECOPD patients with decompensated hypercapnic ARF was conducted. Each patient underwent 30 min of treatment with both NIV and HFNO, with the neural respiratory drive (NRD) measured via a multi-pair oesophageal electrode catheter. Results: = 0.001). Both HFNO and NIV enhanced NRD efficiency relative to conventional oxygen therapy (COT). Furthermore, NIV led to more pronounced improvements in inspiratory workload, respiratory muscle contraction, and work of breathing-evidenced by reductions in Peso, Pdi, PTPdi/breath, and PTPdi/min-compared with both COT and HFNO. HFNO also demonstrated physiological benefits over COT, with the unexpected exception of the neuro-mechanical efficiency and PTPdi/breath. Conclusion: In AECOPD patients with decompensated hypercapnic ARF, NIV significantly enhances NRD efficiency and reduces respiratory workload and related respiratory mechanics. HFNO, while less effective than NIV, still confers measurable physiological benefits and may serve as a viable alternative in resource-limited settings or those who are intolerant to NIV, potentially more appropriate for patients with less severe respiratory failure. Trial registration: ClinicalTrials.gov, NCT04212182. Registered 23 December 2019, https://clinicaltrials.gov/study/NCT04212182.