Predictive performance of ROX index and its variations for NIV failure.

OBJECTIVE

To determine whether the ROX index and its variations can predict the risk of intubation in ICU patients receiving NIV ventilation using large public ICU databases.

DESIGN

Retrospective observational cohort study.

SETTING

Patient data was extracted from both the AmsterdamUMCdb and the MIMIC-IV ICU databases, which contained data related to 20,109 and 50,920 unique patients.

PATIENTS

Non-invasively mechanically ventilated.

INTERVENTIONS

Retrospective review of variables.

MAIN VARIABLES OF INTEREST

To assess the predictive values of models for each index, the ROX and its variations mROX, ROX-HR and mROX-HR were calculated based on mean values of SpO, respiratory rate, FiO and PaO from 2-h windows within the first 12 h of NIV.

RESULTS

3344 patients were eligible for analysis of which 1344 were intubated, died or returned to NIV within 24 h of ending NIV. NIV failure group had higher SOFA scores and higher CRP levels at admission. There was no difference in duration of NIV therapy or 28-day mortality, but patients who failed NIV had longer length of stay. The best performing index was ROX with an AUROC of 0.626 at 10-12 h. All other indices for all other time windows were less discriminating.

CONCLUSIONS

The performance of ROX index and its variations to predict NIV failure in ICU patients across large public ICU databases was moderate at best and cannot currently be recommended for clinical decision support.