Comparison of ROX Index and Updated HACOR Score to Predict Failure of Noninvasive Ventilation in Patients Admitted with Type 2 Respiratory Failure in the Intensive Care Unit

Abstract

Background: Type 2 respiratory failure (T2RF) is a life-threatening condition commonly managed with non-invasive ventilation (NIV) in the intensive care unit (ICU). Early identification of patients at risk of NIV failure is critical for timely intervention and improved outcomes. This study compares the effectiveness of the ROX index and the updated HACOR score in predicting NIV failure among T2RF patients.

Methods: A prospective observational study was conducted on 48 patients diagnosed with T2RF and treated with NIV in the ICU. The ROX index and updated HACOR score were calculated for each patient, and their predictive accuracies were analyzed. Clinical parameters, arterial blood gas (ABG) values, and patient outcomes were closely monitored to assess NIV success or failure.

Results: The findings demonstrated that the ROX index was a significant predictor of NIV failure, with lower values at 2 and 12 hours correlating strongly with the need for intubation. The HACOR score showed predictive value but was less accurate than the ROX index. Early identification of NIV failure using the ROX index was associated with reduced mortality and morbidity related to delayed intubation.

Conclusion: The ROX index is a reliable predictor of non-invasive ventilation (NIV) failure in type 2 respiratory failure, showing superior and consistent performance at 12 and 24 hours. While the updated HACOR index offers early predictive value, its accuracy declines over time. The original HACOR index is less sensitive overall. These findings support the ROX index as the most practical tool for guiding NIV management.