Optimised oxygenation improves functional capacity during daily activities in patients with COPD on long-term oxygen therapy – a randomised crossover trial

Abstract

ABSTRACTBackgroundMinimising hypoxemia during submaximal walking tests has a positive effect on exercise capacity and dyspnea in patients with COPD on long-term oxygen therapy (LTOT). However, the impact of optimising oxygenation during everyday tasks remains unexplored. Therefore, we investigated the effects of maintaining a target saturation on activities of daily living (ADL) using automated oxygen titration compared to conventional fixed oxygen flow.MethodsIn a double-blinded, randomised crossover trial, 31 patients with COPD on LTOT performed two GlittreADL tests to assess the functional capacity of everyday activities using a) their fixed oxygen dose and b) an adjusted flow from 0-8 L/min targeting a SpO2of 90-94%. A closed-loop device automatically titrated the oxygen based on information from a Bluetooth wrist pulse oximeter.ResultsThe patients reduced the time to perform the ADL-test by median (IQR) 38 (12–73) seconds, p<0.001, using automated titration compared to the fixed oxygen flow. The oxygen flow in the automated arm more than tripled to 5.4 (4.1–6.8) vs. 1.6 (1.1–2.1) L/min (fixed) during the test, p<0.001, while the time spent within SpO2-target was increased from 19% to 49%, p=0.002. Correspondingly, the patients experienced less dyspnea (BorgCR10); 5 (3–7) vs. 6 (4–8), p<0.001, in favour of the automated oxygen titration.ConclusionsImproving oxygenation and extending the time spent within target saturation reduced dyspnea and improved functional capacity in activities of daily living in patients with COPD on LTOT.Trial registration numberNCT05553847