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🫁 ROX Index (HFNC Outcome)

UseMonitor response to HFNC and flag impending failure.

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SourceRoca O, et al. Am J Respir Crit Care Med 2019

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Scene next step
📋resp failureOpen scene pack →
Related scores
Matching pathway
🧭pe_dxOpen pathway →
Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

Assess at ~2, 6 and 12 hours of HFNC.

When to use

Monitor response to HFNC and flag impending failure.

How it works

ROX = (SpO₂% / FiO₂) / respiratory rate. ≥ 4.88 predicts success; < 3.85 suggests failure.

Key points

  • Assess at ~2, 6 and 12 hours of HFNC.
  • Persistently low values warrant considering intubation.
  • Combines oxygenation and respiratory drive in one number.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

SpO₂94 %
FiO₂0.5 fraction
Respiratory rate24 /min

→ROX index7.83

  • Interpretation：≥ 4.88 — lower risk of HFNC failure.
  • Formula：(SpO₂% / FiO₂) / respiratory rate
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using ROX Index (HFNC Outcome)?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does ROX Index (HFNC Outcome) upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is ROX Index (HFNC Outcome) calculated in practice? Can you show a worked example?
Inputs: SpO₂ 94 %, FiO₂ 0.5 fraction, Respiratory rate 24 /min → Result: ROX index 7.83（Interpretation: ≥ 4.88 — lower risk of HFNC failure., Formula: (SpO₂% / FiO₂) / respiratory rate）
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