VistaMed (Ireland)

Introduction: Pulsed oxygen via portable oxygen concentrators (POC) has expanded in popularity recently. Some studies have shown modern POCs can be as effective as other oxygen delivery devices, and some users express preference to use their POCs across all daily activity. However, concerns remain that they are not effective during sleep or at very high respiratory rates. Bench testing may therefore help identify key determinants of pulsed-oxygen device efficacy. This bench investigation examined adequacy of POC pulse triggering across a span of user breathing behaviours. Methods: Three contemporary devices were bench-evaluated across three simulated adult breathing behaviours: exertion (tidal volumes 234mL-700mL at rates 20/min-34/min), small patient at rest (tidal volume 304mL at 17/min), & oronasal breathing during sleep (nasal tidal volume 182mL at 17.6/min). Emphasis was placed on achieving respiratory flow patterns representative of oxygen users, guided by published clinical data. The bench ‘nose’ was printed from MRI data from an average height adult Caucasian male. Results: All POCs performed well during simulated COPD patient breathing during exertion, and for the small patient at rest. For the scenario of oronasal breathing during sleep (nasal volume 182mL), 100% synchrony was also found to be achievable, but not in all devices. Conclusions: The results are supportive of contemporary POC triggering abilities across diverse behaviours, even in the presence of substantial oronasal breathing. Further research into these and other topics affecting pulsed oxygen efficacy may help realise patients’ aspirations for smaller and more efficient oxygen therapy.