Outcomes and characteristics of COVID-19 patients treated with CPAP/ HFNO outside of the intensive care setting

Sykes, Dominic L; Crooks, Michael G; Thu Thu, Khaing; Brown, Oliver I; Tyrer, Theodore J p; Rennardson, Jodie; Littlefield, Catherine; Faruqi, Shoaib

BACKGROUND: Continuous Positive Airway Pressure (CPAP) and High Flow Nasal Oxygen (HFNO) have been used to manage hypoxaemic respiratory failure secondary to COVID-19 pneumonia. Limited data are available for patients treated with non-invasive 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 non-invasive respiratory support outside of the intensive care setting. RESULTS: We report the outcomes of 140 patients (Mean Age=71.2 [sd=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.