Comparison of Portable Oxygen Concentrators and Inspired Oxygen Levels in a Model of Respiratory Failure - PubMed (original) (raw)
Comparison of Portable Oxygen Concentrators and Inspired Oxygen Levels in a Model of Respiratory Failure
Douglas S Gardenhire et al. Pulm Ther. 2025 Dec.
Abstract
Introduction: This bench study evaluated the inspired oxygen fraction (FiO2) delivered by different portable oxygen concentrators (POCs) compared to wall oxygen and a standalone concentrator (control device) using a respiratory failure-specific lung simulator replicating an adult with chronic respiratory disease at respiratory rates of 15, 20, 30, and 40 breaths per minute.
Methods: A lung simulator replicated an adult with chronic lung disease in respiratory failure. POCs and controls were tested at device-specific settings 2, 3, 5, and 6. One-way analysis of variance (ANOVA) assessed FiO2 differences when more than two groups were compared; independent t tests were used for two-group comparisons.
Results: Wall oxygen generally delivered higher FiO2 across all settings and respiratory rates. At 40 breaths/min and setting 2, however, the CAIRE FreeStyle® Comfort® with autoSAT® delivered a slightly higher FiO2 than wall oxygen (0.25 vs. 0.24, p < 0.01). Among POCs, the CAIRE FreeStyle® Comfort® (with or without autoSAT®) achieved the highest FiO2 values at elevated respiratory rates, while devices like the Inogen G4® and G5® performed more variably and showed reduced oxygen delivery at higher breathing frequencies.
Conclusions: Wall oxygen and standalone concentrators consistently outperformed POCs across most breathing conditions. While the CAIRE FreeStyle® Comfort® with autoSAT® offered relative advantages at high respiratory rates, most POCs may not adequately sustain oxygenation during exertion or stress. These findings inform home oxygen therapy decisions, emphasizing the importance of device selection based on respiratory demand. Clinical validation of these bench findings is warranted.
Keywords: Chronic obstructive pulmonary disease; Home oxygen therapy; Obstructive lung disease; Oxygen therapy; Portable oxygen concentrators; Respiratory care.
© 2025. The Author(s).
Conflict of interest statement
Declarations. Conflict of Interest: Dr. Douglas S. Gardenhire received an unrestricted grant from CAIRE Inc. for salary support for the faculty. No other author has any relationship or any financial ties to CAIRE. Mr. Robert B. Murray has nothing to disclose. Mrs. Robin E. Gardenhire has nothing to disclose. Dr. Kyle J. Brandenberger has nothing to disclose. Dr. Gerald S. Zavorsky has nothing to disclose. Ethical Approval: This article is based on previously conducted studies and does not contain any new studies with human participants or animals performed by any of the authors.
Figures
Fig. 1
The different brands of portable oxygen concentrators, including one standalone oxygen concentrator used in this study
Fig. 2
Mean fraction of inspired oxygen (FiO2) delivered by different oxygen delivery systems across various flow settings and respiratory rates. Each cell displays the mean FiO2 value measured at a specific flow rate (in liters per minute, L/min) and respiratory rate (in breaths per minute, (breaths/min), shown as Setting e.g., 2–15. The color scale represents the magnitude of FiO2, with lighter shades indicating lower oxygen concentrations and deeper blue shades indicating higher FiO2 delivery. Devices tested include Wall Oxygen (control), CAIRE® Companion 5™ SOC, CAIRE® FreeStyle Comfort (FSC) with and without autoSAT® (sensitivity levels 2 and 5), Philips SimplyGo Mini, GCE Zen-O Lite (Pulse and Eco modes), Drive DeVilbiss iGo® 2, and Kingon P2. Statistical significance across groups is indicated below each column using F-ratios, degrees of freedom (df), and p values: For example: F = 82.6, df = 11, p < 0.01 for the 2–15 setting. This visualization highlights that wall oxygen achieves highest FiO2 at all settings; CAIRE FSC (autoSAT®) performs best among POCs but still falls short of wall oxygen at high RR (30–40 bpm)
Fig. 3
Mean fraction of inspired oxygen (FiO2) delivered by different oxygen delivery systems across various flow settings and respiratory rates. Each cell displays the mean FiO2 value measured at a specific flow rate (in liters per minute, L/min) and respiratory rate (in breaths per minute, (breaths/min), shown as Setting e.g., 2–15. The color scale represents the magnitude of FiO2, with lighter shades indicating lower oxygen concentrations and deeper red shades indicating higher FiO2 delivery. Devices tested include Wall Oxygen (control), CAIRE Companion 5™ SOC (control), Inogen One® G4®, and Inogen One® G5®. Missing values are shaded in gray, indicating unmeasured or non-applicable conditions. Statistical significance is indicated below the axis with paired t test results comparing device performances: t = − 23.8, − 73.9, − 34.5, − 28.5, df = 16, p ≤ 0.01; t = − 55.6, − 37.1, − 50.5, − 66.0, df = 16, p < 0.01. The results clearly shows Inogen G4® and G5® deliver substantially lower FiO2 than controls at equivalent settings. There are significant differences in FiO2 delivery between devices across a range of clinically relevant settings. Wall oxygen FiO2 remains around 0.38–0.45 at setting 5, even at high respiratory rates, whereas most POCs drop to 0.25–0.30. F-ratio results are presented in Fig. 2