High-Flow Nasal Cannula therapy: A Feasible Treatment in Vulnerable Older COVID-19 Patients on the Wards

Background: In the midst of the COVID-19 crisis, many frail elderly were admitted to our hospital with COVID-19. We sought a treatment for those who had severe respiratory failure but were not eligible for invasive mechanical ventilation, due to frailty, functional status, comorbidity or wish of the patient. We started with applying High-flow nasal cannula (HFNC) treatment on the wards.Methods: A retrospective cohort study amongst COVID-19 adult patients with respiratory failure defined as persisting hypoxemia despite maximum conventional oxygen administration requiring invasive mechanical ventilation at the Intensive Care Unit (ICU) but being treated with HFNC as they were non-eligible due to frailty or wish of the patient.Results: We included 32 patients between March 9 and May 1, 2020. The median age was 79.0 years (74.5-83.0) with a median of three comorbidities (3-4) and a median Clinical Frailty Score of 4 out of 9 (3-6). The median SPO2/FiO2 Ratio was 157.5 indicating moderate ARDS. Overall survival rate in the HFNC cohort was 25%. Age (80.5 (78.0-84.3) vs 69.5 (65.5-74.3) p=0.0040) and hypertension (92% vs 25%, p=0.0008) were associated with mortality.Conclusion: HFNC can be used as a last resort respiratory management strategy in vulnerable elderly COVID-19 patients in respiratory failure on the wards who failed on conventional high dose oxygen supply and are not eligible for invasive mechanical ventilation.