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🧴 Total Body Water (Watson)

UseWhen to use: sodium / free-water calculations needing a TBW estimate.

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StrataProvides liters of TBW and TBW/weight fraction.

LimitsWhen not to use: anasarca / ICU extremes without caveat. · Pitfall: height in inches. · Estimate only.

SourceWatson PE et al. anthropometric TBW equations

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

Watson TBW.

When to use

When to use: sodium / free-water calculations needing a TBW estimate.

How it works

Watson male/female equations from age, height, weight.

Key points

  • Watson TBW.
  • Anthropometric.
  • Next: free-water math.

References

  • Watson PE et al. anthropometric TBW equations

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.

SexMale
Age50 years
Height170 cm
Weight70 kg

→TBW (Watson)39.5L

  • TBW/weight：56.4%
  • Cue：TBW/weight within common adult teaching range
SexFemale
Age50 years
Height170 cm
Weight70 kg

→TBW (Watson)33.3L

  • TBW/weight：47.6%
  • Cue：TBW/weight within common adult teaching range
Verification & sources · governance
FAQ

Frequently asked questions

Does Total Body Water (Watson) 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 Total Body Water (Watson) calculated in practice? Can you show a worked example?
Inputs: Sex Male, Age 50 years, Height 170 cm, Weight 70 kg → Result: TBW (Watson) 39.5 L（TBW/weight: 56.4%, Cue: TBW/weight within common adult teaching range） Inputs: Sex Female, Age 50 years, Height 170 cm, Weight 70 kg → Result: TBW (Watson) 33.3 L（TBW/weight: 47.6%, Cue: TBW/weight within common adult teaching range）
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