Background. High-flow nasal cannula (HFNC) is an oxygen delivery method shown to reduce the risk of intubation and mortality in patients with type 1 respiratory failure. The ROX-index score can predict HFNC failure. This study aims to evaluate sequential ROX-index assessments as predictors of HFNC failure and mortality. Methods. Prospective observational single-center study including all adult patients with positive SARS-CoV-2 PCR placed under HFNC from 1st November 2020 to 31st May 2021, and patients with hemodynamic instability or unable to tolerate HFNC were excluded. The primary endpoint was successful HFNC de-escalation. Results. In univariate analysis, HFNC de-escalation was associated with younger age (59.2 ± 14 vs. 67.7 ± 10.5 and ), lower levels of serum lactate (1.1 vs. 1.5 and ), and higher ROX-index at 12 hrs (5.09 vs. 4.13 and ). ROC curve analysis of ROX-index at 12 hrs yielded a c-statistic of 71.2% (95% CI 61.6–80.9 and ). ROX-index at 12 hrs and age retained significance in multivariate analysis. Using an optimal cutoff point of 4.43, we calculated a sensitivity of 64.5% and specificity of 69.6%. In univariate survival analysis, older age (68.8 ± 9.7 vs. 58.9 ± 13.9 and ), greater creatinine values (0.96 vs. 0.84 and ), greater SOFA score (), and a lower 12 hrs ROX-index (4.22 vs. 4.95 and ) were associated with hospital mortality. The SOFA score and age retained significance in multivariate survival analysis. Conclusion. ROX-index is proven to be a valuable and easy-to-use tool for clinicians in the assessment of COVID-19 patients under HFNC.

中文翻译：

---

超过 12 小时的序贯 ROX 指数评分在预测通过高流量鼻插管接受氧气的 COVID-19 患者治疗失败和死亡率方面的验证

背景。高流量鼻插管 (HFNC) 是一种氧气输送方法，可降低 1 型呼吸衰竭患者的插管风险和死亡率。ROX 指数评分可以预测 HFNC 失败。本研究旨在评估连续 ROX 指数评估作为 HFNC 失败和死亡率的预测指标。方法。前瞻性观察性单中心研究包括从 2020 年 11 月 1 日至 2021 年 5 月 31 日接受 HFNC 治疗的所有 SARS-CoV-2 PCR 阳性成年患者，以及血液动力学不稳定或无法耐受 HFNC 的患者被排除在外。主要终点是 HFNC 成功降级。结果。在单变量分析中，HFNC 降级与较年轻相关（59.2 ± 14 对 67.7 ± 10.5 和)，血清乳酸水平较低（1.1 对 1.5 和)，以及 12 小时时更高的 ROX 指数（5.09 对比 4.13 和). 12 小时时 ROX 指数的 ROC 曲线分析得出的 c 统计量为 71.2%（95% CI 61.6–80.9 和). 12 小时和年龄的 ROX 指数在多变量分析中保持显着性。使用 4.43 的最佳截止点，我们计算出 64.5% 的灵敏度和 69.6% 的特异性。在单变量生存分析中，年龄较大（68.8 ± 9.7 对 58.9 ± 13.9 和)，更高的肌酐值（0.96 对 0.84 和),更高的 SOFA 得分 ()，以及较低的 12 小时 ROX 指数（4.22 对比 4.95 和)与医院死亡率有关。SOFA 评分和年龄在多变量生存分析中保持显着性。结论。ROX-index 被证明是一种有价值且易于使用的工具，可供临床医生评估 HFNC 下的 COVID-19 患者。