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🩺 Thyromental Distance / Ratio (Airway)

UseWhen to use: pre-intubation / pre-anesthesia airway assessment.

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StrataTMD <6–6.5 cm is a classic difficulty cue — combine with other predictors.

LimitsWhen not to use: as the only airway predictor. · Pitfall: measuring without full extension. · Not a sole intubation plan.

SourceThyromental distance (Patil) airway screening measure

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.

Paste the link in Slack, Teams, X, or LinkedIn — the preview image comes from this page’s Open Graph card.

Methodology · worked example, guidelines & full notes
Clinical takeaway

Patil TMD.

When to use

When to use: pre-intubation / pre-anesthesia airway assessment.

How it works

TMD (cm); optional ratio TMD/NC (some series flag <≈0.23).

Key points

  • Patil TMD.
  • Optional TMD/NC.
  • Next: Mallampati / LEMON.

References

  • Thyromental distance (Patil) airway screening measure

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.

Thyromental distance6.5 cm
Neck circumference (optional)40 cm

→TMD6.5cm

  • TMD：6.5 cm
  • TMD/NC ratio：0.163
  • Cue：≈6–6.5 cm — borderline; combine with Mallampati/LEMON
Verification & sources · governance
FAQ

Frequently asked questions

Does Thyromental Distance / Ratio (Airway) 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 Thyromental Distance / Ratio (Airway) calculated in practice? Can you show a worked example?
Inputs: Thyromental distance 6.5 cm, Neck circumference (optional) 40 cm → Result: TMD 6.5 cm（TMD: 6.5 cm, TMD/NC ratio: 0.163, Cue: ≈6–6.5 cm — borderline; combine with Mallampati/LEMON）
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