Objective: This study was performed to determine the outcomes of patients with coronavirus disease 2019 (COVID-19) who developed hypoxemic respiratory failure necessitating high-flow nasal cannula (HFNC) therapy and to identify the predictors of HFNC therapy success.
Methods: This retrospective observational study involved all patients treated with HFNC therapy at a center for COVID-19 in Viet Nam from August to October 2021.
Results: The study recruited 302 patients. Of these 302 patients, 171 (56.6%) underwent successful HFNC therapy, and the all-cause mortality rate was 33.44%. Non-critical COVID-19 and a higher respiratory rate-oxygenation (ROX) index at 48 hours after initiating HFNC therapy were independently correlated with HFNC therapy success. The statistically significant predictors of HFNC therapy success were younger age, non-critical COVID-19, a higher platelet count when starting HFNC therapy, and a higher ROX index at 24, 36, and 48 hours after HFNC therapy initiation.
Conclusions: HFNC therapy appears to be effective in patients with COVID-19 who develop respiratory failure requiring respiratory support. Non-critical COVID-19 and a higher ROX index measured 48 hours after HFNC therapy initiation might serve as predictive factors for the success of HFNC therapy.
Keywords: Acute respiratory distress syndrome; COVID-19; developing country; high-flow nasal cannula; intensive care unit; respiratory rate–oxygenation index.