Portable low-flow nasal oxygen versus ambient air in patients with chronic lung disease and exercise-induced hypoxaemia: a randomised controlled crossover non-inferiority trial.
Mona Lichtblau, Carmen Wick, Anna Titz, Julian Müller, Simon Raphael Schneider, Dinah Hertig, Zoe Bousraou, Alessandro Vella, Michael Furian, Malcolm Kohler, Esther Irene Schwarz, Silvia Ulrich
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引用次数: 0
Abstract
Background: Exercise-induced desaturation is a common symptom in chronic lung disease (CLD) and is associated with functional limitation and increased mortality. Although portable low-flow supplemental oxygen therapy (SOT) is commonly prescribed for exercise-induced hypoxaemia, evidence for SOT to improve performance is inconsistent.
Method: This pragmatic, randomised, controlled, non-inferiority crossover trial enrolled patients with chronic obstructive pulmonary and interstitial lung disease who exhibited exercise-induced oxygen desaturation of >3%. Each patient performed two 6-minute walk distance (6MWD) tests in randomised order: one breathing ambient air and one using low-flow SOT delivered by a portable backpack concentrator (1-2 L/min). The primary outcome was 6MWD, secondary outcomes included perceived exertion and preference of the interventions. A predefined non-inferiority margin of 35 m was used.
Results: Forty patients were enrolled (mean age 66±13 years; 14 women; 20 with chronic obstructive pulmonary disease (COPD), 20 with interstitial lung disease (ILD)). The mean difference in 6MWD between ambient air and SOT was 0 m (95% CI -14 to 13 m; p<0.001 for non-inferiority). Secondary outcomes demonstrated significantly lower dyspnoea scores with SOT both overall and within COPD/ILD subgroups. Patient preferences were split, with 49% favouring ambient air and 51% preferring SOT. A clinically meaningful improvement in 6MWD of >35 m was found in five patients.
Conclusion: In patients with CLD and exercise-induced desaturation, ambient air was non-inferior to pulsed low-dose SOT by portable concentrator in 6MWD, but SOT improved dyspnoea. These findings highlight the need for more effective, patient-acceptable oxygen delivery systems and further research to identify responders to SOT.
期刊介绍：
BMJ Open Respiratory Research is a peer-reviewed, open access journal publishing respiratory and critical care medicine. It is the sister journal to Thorax and co-owned by the British Thoracic Society and BMJ. The journal focuses on robustness of methodology and scientific rigour with less emphasis on novelty or perceived impact. BMJ Open Respiratory Research operates a rapid review process, with continuous publication online, ensuring timely, up-to-date research is available worldwide. The journal publishes review articles and all research study types: Basic science including laboratory based experiments and animal models, Pilot studies or proof of concept, Observational studies, Study protocols, Registries, Clinical trials from phase I to multicentre randomised clinical trials, Systematic reviews and meta-analyses.
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