Oxygen Efficient Respiratory Aid (OXERA) Device: A Safety Study

Abstract

Background: Severe Coronavirus Disease 2019 (COVID-19) can develop pneumonia with acute respiratory distress, acute hypoxia, and/or death. The Oxygen Efficient Respiratory Aid (OxEraTM) device has been granted SAHPRA approval for emergency COVID-19 pandemic use. The device has the potential to be used widely in the healthcare sector due to its efficient oxygen supply and adjustable wall positive expiratory pressure (PEP). Objectives: We assessed whether the OxEraTM device was safe to use in a healthy adult volunteer population. Our primary objective was to ensure there was no asphyxiation, as assessed by changes observed from baseline End Tidal Carbon Dioxide (ETCO2) exceeding 6.3 mmHg and above the 45mmHg threshold. We also monitored changes in vital organ signs and assessed the pain and comfort of the participant at various intervals with changes in PEPs. Methods: This was an experimental safety study of the OxEraTM Device on 30 healthy participants at the Intensive Care Unit training centre of Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa. Each participant had basic vital signs, ETCO2, and Oxygen saturation percentages (SpO2%) taken at baseline until the end of 2 hours. In the first 20 minutes, the PEP was increased by 5cmH20 every 5 minutes to a maximum of 20 cmH20. Then continued for the rest of the time on a PEP of 5 cmH20. At each interval, vital signs, subjective comfort, pain, and visual scores were measured. Results: Thirty healthy participants were enrolled for the experimental study. There was no significant difference in ETCO2 from baseline until 2 hours. No participant experienced an increase in measured ETCO2 greater than 45 mmHg and no increase in ETCO2 from baseline was greater than 6.3mmHg. The median increase in ETCO2 over the study period was 2mmHg. There were no significant changes in respiratory rate. The heart rate decreased significantly from a median of 73(IQR 65-87) to 68.5(IQR 63-75) at the end of the 2 hours. There were no significant changes in the blood pressure over the study. The visual analogue scale (VAS) score and comfort score had a significant increase over the 2 hours from baseline of 0 to 2 at maximum; however, the pain analogue scale (PAS) scores showed no significant increase. 9 Conclusion: Overall the OxEraTM device achieved the safety endpoints set out. There was no sign of asphyxiation and there were appropriate physiological responses to changes in PEP once applied. The comfort of the mask did worsen over the 2 hours; however, the scores were minimally worse on PEP application but improved once-off PEP. No adverse event were recorded at all.