Predictors of high-flow nasal cannula outcome in acute respiratory failure — a single-center retrospective cohort study

Abstract Background High-flow nasal cannula (HFNC) has been used increasingly and tried as an alternative and a promising strategy in treating acute respiratory failure to reduce mortality and adverse events associated with mechanical ventilation. Aim Evaluate predictors of a high-flow nasal cannula (HFNC) outcome in managing acute respiratory failure in adult patients in the RICU. Patients and methods The study was a retrospective cohort study on patients with acute respiratory failure of respiratory causes who were admitted to the respiratory intensive care unit (RICU) at Kafrelsheikh University Hospital from January 2023 to July 2024, among which 35 patients who had HFNC treatment were retrospectively analyzed. The group that switched from HFNC treatment to conventional oxygen therapy (COT) was defined as the HFNC success group (Group I), and the group that switched from HFNC treatment to non-invasive or invasive ventilation was defined as the HFNC failure group (Group II). Results The study enrolled 35 patients, 19 males, and 16 females, with mean ± SD of their age years 59.83 ± 17.08; treatment success occurred in 16 of 35 patients (46%) treated with HFNC therapy. The HFNC success group demonstrated more notable improvement in RR,ROX index and PaO2/Fio2 in the multivarient analysis. The multivariate logistic regression analysis revealed that respiratory rate (RR) after 2, 6, and 24 h, Na, FiO 2 after 24 h, flow after 6 h, SpO 2 or PaO 2 after 2 and 6 h, PaO 2 /FiO 2 or SpO 2 /FiO 2 after 24 h, and ROX index after 6 and 24 h were the only significant predictors for HFNC success. Conclusion In patients with acute respiratory failure treated with HFNC, the ROX index with other respiratory variables can help identify those at low and high risk of treatment failure.