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    Patent Pending

    ROX Index for Intubation after HFNC

    Predicts high-flow nasal cannula (HFNC) failure/need for intubation.


    Launched during COVID-19 crisis.


    In the original paper, patients started on HFNC were reassessed at 2, 6, and 12 hours; patients whose scores were in the "indeterminate" range (3.85-4.87) were reassessed two hours later. These scores were trended over time in patients.

    When to Use
    Why Use

    After HFNC during reassessment, the ROX Index can help suggest which patients will fail HFNC and need to progress to intubation for further ventilatory support.

    • See our table below for common estimates of FiO₂ based on oxygen delivery device and oxygen flow rates.

    • A higher index is "better," as it suggests a better oxygen saturation, a lower FiO₂ requirement, and/or less tachypnea.

    While not externally validated, the ROX Index is a simple bedside calculation using three clinical variables and is one easy way to summarize a patient's degree of hypoxemic respiratory failure; it was created and studied to predict need for intubation post-HFNC, which is of particular importance in COVID-19.

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    Creator Insights
    Dr. Oriol Roca

    About the Creator

    Oriol Roca, MD PhD, is a critical care specialist at the Vall d'Hebron University Hospital in Barcelona, Spain. Dr. Roca’s primary research is focused on clinical predictors and respiratory support success in acute respiratory distress syndrome.

    To view Dr. Oriol Roca's publications, visit PubMed

    Are you Dr. Oriol Roca? Send us a message to review your photo and bio, and find out how to submit Creator Insights!
    MDCalc loves calculator creators – researchers who, through intelligent and often complex methods, discover tools that describe scientific facts that can then be applied in practice. These are real scientific discoveries about the nature of the human body, which can be invaluable to physicians taking care of patients.
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