🌡️ SIRS Criteria Calculator
UseScreen for systemic inflammation; with infection, prompt sepsis evaluation.
StrataSIRS ≥2 is nonspecific; for suspected infection prefer qSOFA/SOFA (Sepsis-3) over SIRS alone.
LimitsSIRS is neither sensitive nor specific for sepsis — avoid using it as… · Steroids, beta-blockers and hematologic disease alter HR/WBC criteria. · Pair with lactate, cultures and organ-dysfunction assessment.
SourceBone RC, et al. Chest 1992 (ACCP/SCCM)
This-shift next steps
After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.
- Who it is for
- Adults with suspected infection when deciding whether to treat this hour as sepsis.
- Who it is not for
- Stable patients scored only to fill a number. Children do not follow adult bundle dosing.
- Formula and variables
- qSOFA is respiratory rate, systolic pressure, and mentation. NEWS2 is respiration, oxygenation, supplemental oxygen, blood pressure, pulse, consciousness, and temperature. SOFA is six organ systems. MEWS stays off the main door. Weights stay as on this page. qSOFA is not a diagnosis.
- Result → next step
- A positive screen only escalates assessment. Next page is the sepsis bundle. qSOFA alone must not switch on antibiotics. Antimicrobials stay at drug-class direction; the spectrum page may be opened. No numeric dose here.Sepsis bundle →
- Guideline
- SSC 2021
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Methodology · worked example, guidelines & full notes
Non-specific — many non-infectious causes.
When to use
Screen for systemic inflammation; with infection, prompt sepsis evaluation.
How it works
1 point each: temp > 38 or < 36°C; HR > 90; RR > 20 or PaCO₂ < 32; WBC > 12 or < 4 ×10⁹/L or > 10% bands. ≥ 2 = SIRS.
Key points
- Non-specific — many non-infectious causes.
- Sepsis-3 favours qSOFA/SOFA for risk stratification.
- Still used for screening alongside clinical judgement.
References
- [Guideline / primary source]Bone RC, et al. Chest 1992 (ACCP/SCCM)
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.
| Temperature > 38°C or < 36°C | No |
|---|---|
| Heart rate > 90/min | No |
| RR > 20/min or PaCO₂ < 32 mmHg | No |
| WBC > 12 or < 4 ×10⁹/L or > 10% bands | No |
→SIRS criteria0/4
- Interpretation：< 2 criteria.
| Temperature > 38°C or < 36°C | Yes |
|---|---|
| Heart rate > 90/min | Yes |
| RR > 20/min or PaCO₂ < 32 mmHg | Yes |
| WBC > 12 or < 4 ×10⁹/L or > 10% bands | Yes |
→SIRS criteria4/4
- Interpretation：≥ 2 criteria met = SIRS. With suspected infection, evaluate for sepsis.
Verification & sources · governance
FAQ
Frequently asked questions
- Does SIRS Criteria Calculator 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 SIRS Criteria Calculator calculated in practice? Can you show a worked example?
- Inputs: Temperature > 38°C or < 36°C No, Heart rate > 90/min No, RR > 20/min or PaCO₂ < 32 mmHg No, WBC > 12 or < 4 ×10⁹/L or > 10% bands No → Result: SIRS criteria 0 /4（Interpretation: < 2 criteria.） Inputs: Temperature > 38°C or < 36°C Yes, Heart rate > 90/min Yes, RR > 20/min or PaCO₂ < 32 mmHg Yes, WBC > 12 or < 4 ×10⁹/L or > 10% bands Yes → Result: SIRS criteria 4 /4（Interpretation: ≥ 2 criteria met = SIRS. With suspected infection, evaluate for sepsis.）