High-flow nasal cannula oxygen therapy for the treatment of acute respiratory failure secondary to SARS-CoV-2 pneumonia out of ICU.

Introduction And Objectives: High-flow nasal cannula oxygen therapy (HFNC) has been successfully used for the treatment of acute hypoxaemic respiratory failure (AHRF) secondary to SARS-CoV-2 pneumonia and being effective in reducing progression to invasive mechanical ventilation. The objective of this study was to assess the usefulness of HFNC on a hospital ward for the treatment of AHRF secondary to SARS-CoV-2 pneumonia and its impact on the need for intensive care unit (ICU) admission and endotracheal intubation. Other objectives include identifying potential physiological parameters and/or biomarkers for predicting treatment failure and assessing the clinical course and survival.

Methods: Observational study based on data collected prospectively between March 2020 and February 2021 in a single hospital on patients diagnosed with AHRF secondary to SARS-CoV-2 pneumonia who received HFNC outside an ICU.

Results: One hundred and seventy-one patients out of 1090 patients hospitalised for SARS-CoV-2 infection. HFNC was set as the ceiling of treatment in 44 cases; 12 survived (27.3%). Among the other 127 patients, intubation was performed in 25.9% of cases with a mortality of 11.8%. Higher creatinine levels (OR 1.942, 95% CI 1.04; 3.732; p = 0.036) and Comorbidity-Age-Lymphocyte-LDH (CALL) score (OR 1.273, 95% CI 1.033; 1.617; p = 0.033) were associated with a higher risk of intubation. High platelet count at HFNC initiation was predictive of good treatment response (OR 0.935, 95% CI 0.884; 0.983; p = 0.012).

Conclusions: HFNC outside an ICU is a treatment with high success rate in patients with AHRF secondary to SARS-CoV-2 pneumonia, including in patients in whom this therapy was deemed to be the ceiling of treatment.