Comparison of Portable Oxygen Concentrators and Inspired Oxygen Levels in a Model of Respiratory Failure

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.

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.

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.

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.