Result:
HFNC failure occurred in 111/286 (39%) infants, and for 56 (50% of the failure) of them within the first 6 hours. The area under the curve of ROX indexes at H0 and H1 were, respectively, 0.56 (95% CI 0.48-0.63, p =0.14), 0.56 (95% CI 0.49- 0.64, p =0.09). HFNC failure was associated with higher mWCAS score at H1 (p<0.01) and lower decrease in EDIN scale during the first hour of HFNC delivery (p = 0.02), but none of the physiological variables were predictive of HFNC failure.