The primary objective of this study was to evaluate whether pediatric respiratory rate-oxygenation index (p-ROXI) and variation in p-ROXI (p-ROXV) can serve as objective markers in children with high-flow nasal cannula (HFNC) failure. In this prospective, single-center observational study, all patients who received HFNC therapy in the general pediatrics ward, pediatric intensive care unit, and the pediatric emergency department were included. High-flow nasal cannula success was achieved for 116 (88.5%) patients. At 24 h, if both p-ROXI and p-ROXV values were above the cutoff point (≥ 66.7 and ≥ 24.0, respectively), HFNC failure was 1.9% and 40.6% if both were below their values (p < 0.001). At 48 h of HFNC initiation, if both p-ROXI and p-ROXV values were above the cutoff point (≥ 65.1 and ≥ 24.6, respectively), HFNC failure was 0.0%; if both were below these values, HFNC failure was 100% (p < 0.001).Conclusion: We observed that these parameters can be used as good markers in pediatric clinics to predict the risk of HFNC failure in patients with acute respiratory failure. What is Known: • Optimal timing for transitions between invasive and noninvasive ventilation strategies is of significant importance. • The complexity of data requires an objective marker that can be evaluated quickly and easily at the patient's bedside for predicting HFNC failure in children with acute respiratory failure. What is New: • Our data showed that combining p-ROXI and p-ROXV can be successful in predicting HFNC failure at 24 and 48 h of therapy.
Keywords: Acute respiratory failure; Children; High-flow nasal cannula; P-ROXI; P-ROXV.