A newly developed ultra-small portable oxygen concentrator with equivalent efficacy to the conventional device

Background: Current portable oxygen concentrators (POC) restrict physical activity in patients prescribed long-term oxygen therapy because of their large size and weight. We have developed an ultra-small POC that is 1/6 the volume and 1/3 the weight of conventional POC and that can be carried on the back [W190 × D60 × H220 mm, 1.87 kg]. Objectives: We examined whether our POC has equivalent efficacy to provide oxygen to patients with chronic lung disease in comparison to conventional POC despite its reduced size and weight. Methods: Patients with chronic obstructive pulmonary disease (COPD) (n = 18), interstitial lung disease (n = 7), bronchial asthma (n = 2), and non-respiratory diseases (n = 3) who showed desaturation during exercise were recruited. After examination with constant load exercise test (CLET) or shuttle walking test (SWT) under breathing room air, subjects performed the same exercise test under breathing 2 L/min oxygen provided by our POC or a conventional POC at random. The desaturation at standardized time near end-exercise (isotime) in each subject during CLET or SWT under breathing 2 L/min oxygen provided by the two POC were compared. Results: Seventeen subjects performed CLET and thirteen subjects performed SWT. There were no significant differences in desaturation at isotime between the developed POC and conventional POC during CLET (isotime SpO2: room air 87.6% ± 0.9%, developed POC 89.9% ± 0.7%, conventional POC 91.1% ± 0.7%) or during SWT (isotime SpO2: room air 87.3% ± 1.7%, developed POC 89.4% ± 1.0%, conventional POC 90.7% ± 0.8%). Conclusion: The newly developed ultra-small POC showed equivalent efficacy for oxygenation to conventional POC.