Outcomes and characteristics of COVID-19 patients treated with continuous positive airway pressure/high-flow nasal oxygen outside the intensive care setting

Abstract

Background Continuous positive airway pressure (CPAP) and high-flow nasal oxygen (HFNO) have been used to manage hypoxaemic respiratory failure secondary to coronavirus disease 2019 (COVID-19) pneumonia. Limited data are available for patients treated with noninvasive respiratory support outside of the intensive care setting. Methods In this single-centre observational study we observed the characteristics, physiological observations, laboratory tests and outcomes of all consecutive patients with COVID-19 pneumonia between April 2020 and March 2021 treated with noninvasive respiratory support outside of the intensive care setting. Results We report the outcomes of 140 patients (mean±sd age: 71.2±11.1, 65% male (n=91)) treated with CPAP/HFNO outside of the intensive care setting. Overall mortality was 59% and was higher in those deemed unsuitable for mechanical ventilation (72%). The mean age of survivors was significantly lower than those who died (66.1 versus 74.4 years, p<0.001). Those who survived their admission also had a significantly lower median Clinical Frailty Score than the non-survivor group (2 versus 4, p<0.001). We report no significant difference in mortality between those treated with CPAP (n=92, mortality: 60%) or HFNO (n=48, mortality: 56%). Treatment was well tolerated in 86% of patients receiving either CPAP or HFNO. Conclusions CPAP and HFNO delivered outside of the intensive care setting are viable treatment options for patients with hypoxaemic respiratory failure secondary to COVID-19 pneumonia, including those considered unsuitable for invasive mechanical ventilation. This provides an opportunity to safeguard intensive care capacity for COVID-19 patients requiring invasive mechanical ventilation.