Contemporary portable oxygen concentrators and diverse breathing behaviours -- a bench comparison

Abstract

BackgroundDecades of clinical research into pulsed oxygen delivery has shown variable efficacy between users, and across a user’s behaviours (sleep, rest, activity). Modern portable oxygen concentrators (POCs) have been shown as effective as other oxygen delivery devices in many circumstances. However, there are concerns that they are not effective during sleep when the breathing is shallow, and at very high respiratory rates as during physical exertion. It can be challenging to examine the determinants of POC efficacy clinically due to the heterogeneity of lung function within oxygen users, the diversity of user behaviour, and measurement issues. Representative bench testing may help identify key determinants of pulsed-oxygen device efficacy.MethodsThree contemporary devices were bench-evaluated across three simulated breathing behaviours: activity, rest, & oronasal breathing during sleep. Emphasis was placed on breathing patterns representative of oxygen users.ResultsAll three POCs performed well during simulated breathing during exertion and at rest. Differences in triggering ability were noted for the scenario of oronasal breathing during sleep.ConclusionsThe results are supportive of contemporary POC triggering abilities. The differences shown in ultimate trigger sensitivity may have relevance to oronasal breathing during sleep or other challenging scenarios for pulsed oxygen delivery, such as dominant mouth breathing during exertion or unfavourable nasal geometry.

Variability in low-flow oxygen delivery by nasal cannula evaluated in neonatal and infant airway replicas

“…In recent years, in vitro methods incorporating realistic upper airway replicas and breathing simulation have emerged to perform highly controlled and repeatable experiments investigating the performance of devices used in respiratory support [ 13 – 21 ]. In principle, such methods allow unlimited variation of input parameters in experiments conducted within an individual ‘subject,’ or airway replica, enabling detailed assessment of underlying fluid mechanics phenomena influencing, for example, gas concentrations and pressures delivered to the upper airways [ 20 , 22 , 23 ].…”

Recent trends in the nanozeolites-based oxygen concentrators and their application in respiratory disorders

“…Bench-wise comparative research between modern portable oxygen concentrators and various breathing techniques was conducted by Martin et al in 2019. Considering three realistic breathing patterns, resting, and oronasal inhalation while sleeping, three modern devices were bench-tested ( 80 ). In Madrid, Spain, patients undergoing portable oxygen therapy were the subject of a telephone-based study conducted by Alises et al in 2019.…”

Improving Breath Detection From Pulsed-Flow Oxygen Sources Using a New Nasal Interface

“…Unreliable breath detection is a well-acknowledged pain point for those who use portable oxygen sources. [17][18][19][20][21] The smallest and most efficient portable oxygen sources use pulsed delivery systems; however, their performance is variable. 18,22 Pulsed-flow oxygen sources rely on pressure-triggering to detect inhalation.…”

“…In particular, patients may not be able to trigger oxygen delivery during sleep, oral breathing, or other circumstances characterized by low nasal inhalation flows. [17][18][19][20][21] Breath detection issues during oral breathing are especially common and may discourage oxygen users from living active lifestyles due to the tendency toward oral breathing during exercise. 23 The reported LTOT patient preference is a single source of portable oxygen that can be used in all breathing scenarios.…”