[A simple nomogram for predicting failure of high-flow nasal cannula in patients with acute hypoxemic respiratory...

Objective: To evaluate the predictive efficacy of a nomogram in patients with acute hypoxemic respiratory failure (AHRF) undergoing treatment with a high-flow nasal cannula (HFNC). Methods: We conducted a retrospective observational study of patients with AHRF who received HFNC treatment. Data on complications, vital signs on the first day after enrollment, use of vasoactive drugs, Glasgow Coma Scale scores, and clinical respiratory parameters (respiratory rate, pulse oximetry oxygen saturation, and fraction of inspired oxygen) were meticulously recorded. The risk ratio for HFNC failure was computed using an online calculator. Results: Overall, 62 patients were included, of which 29 (46.77%) experienced HFNC failure. No significant differences were observed in age, sex, body mass index, complications, or sequential organ failure assessment scores between the two groups. However, compared with those who responded positively to HFNC treatment, individuals experiencing HFNC failure demonstrated a significant increase in acute physiology and chronic health evaluation Ⅱ scores [ (15.15±5.01)score vs. (21.00±5.76)score; P<0.001 ]. Furthermore, HFNC treatment failure was associated with significantly higher ICU mortality rates [0 vs. 34.48%(10/29),P<0.01] and in-hospital mortality rates [3.03%(1/33) vs. 37.93%(11/29),P<0.01], as well as a marked prolongation of ICU stay [6(4,10)d vs. 11(6,17)d, P=0.012]. In the failure group, the nomogram-derived risk ratio was 0.80±0.18, which was significantly higher than that in the success group (0.65±0.18; P=0.009). The area under the receiver operating characteristic curve of the nomogram for predicting HFNC failure was 0.76, with a sensitivity of 54.8% and a specificity of 93.6%. Conclusion: The nomogram, along with the online calculator, offers a straightforward and effective means for assessing the risk of treatment failure in patients with AHRF undergoing HFNC therapy.