Screen infection-related organ dysfunction using SIRS, qSOFA, and a simplified SOFA-style worksheet with sepsis and septic-shock context.
Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Early recognition and timely reassessment matter because delay is associated with worse outcomes.
The definition and screening of sepsis has evolved through three major iterations. **SIRS** (Systemic Inflammatory Response Syndrome) uses four simple bedside criteria (temperature, heart rate, respiratory rate, WBC count) — meeting 2 or more suggests systemic inflammation. While highly sensitive, SIRS is non-specific and can be positive in many non-infectious conditions. The **Sepsis-3 (2016)** definition refined the concept: sepsis is now defined as a suspected or documented infection with an acute increase in **SOFA score ≥ 2**, reflecting organ dysfunction rather than inflammation alone.
For bedside screening, **qSOFA** (quick SOFA) uses just three clinical parameters — systolic BP ≤ 100, respiratory rate ≥ 22, and altered mentation (GCS < 15). A qSOFA ≥ 2 adds context for closer assessment of organ dysfunction. This page provides simultaneous SIRS, qSOFA, and a simplified SOFA-style organ-dysfunction worksheet for educational screening and severity framing. It does not reproduce every ICU-grade SOFA input, so it should be read as context rather than as a formal bedside sepsis protocol.
Sepsis screening is strongest when the bedside criteria and organ-dysfunction data are read together instead of in isolation. This calculator puts SIRS, qSOFA, and SOFA on one page so you can see whether a patient merely meets inflammatory criteria, has bedside signs of higher risk, or already shows organ dysfunction that fits the Sepsis-3 framework.
SIRS: ≥ 2 of [Temp > 38 or < 36°C, HR > 90, RR > 20, WBC > 12 or < 4 ×10³/μL]. qSOFA: ≥ 2 of [SBP ≤ 100, RR ≥ 22, GCS < 15]. Simplified SOFA-style worksheet: respiratory, coagulation, liver, CNS, renal, and a limited cardiovascular proxy are scored from the entered labs/vitals and summed as an educational organ-dysfunction context. Sepsis-3 still defines sepsis as suspected infection plus an acute SOFA increase of at least 2, and septic shock requires persistent hypotension with vasopressor need and lactate > 2 after resuscitation.
Result: SIRS 4/4, qSOFA 2/3, simplified SOFA 6 — sepsis-oriented screen positive
All 4 SIRS criteria are met. qSOFA is 2 (SBP ≤ 100, RR ≥ 22). The page’s simplified SOFA-style organ-dysfunction sum is 6 (renal 2, coag 1, liver 1, respiratory 2), which adds context for serious infection-related organ dysfunction but should still be interpreted with the full clinical picture.
SIRS is sensitive and easy to trigger, which makes it useful for broad screening but weak for specificity. qSOFA is a fast bedside warning tool that highlights patients who may deteriorate outside the ICU. SOFA is more detailed and ties the diagnosis to measurable organ dysfunction. Looking at them together helps separate simple inflammatory response from clinically important sepsis risk.
A positive SIRS result does not prove sepsis, and a negative qSOFA does not safely exclude it. Patients can have infection-related organ dysfunction before the bedside score becomes striking, especially early in the course or after partial treatment. That is why lactate, blood pressure trends, renal function, platelet count, and mental status still matter even when one score looks reassuring.
The practical value of the calculator is in organizing severity signals that often prompt closer review and serial reassessment. A rising SOFA trend, persistent hypotension, or worsening lactate carries more weight than any isolated snapshot, so the scores should support clinical evaluation rather than substitute for bedside review.
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This page calculates true SIRS and qSOFA criteria from the entered bedside values, then adds a simplified SOFA-style organ-dysfunction sum from the labs and vitals collected by the current UI. Because the page does not collect every element needed for a full formal SOFA assessment, the SOFA section should be read as educational severity context rather than as a complete ICU-grade SOFA score. The page is meant to organize screening data, not to replace bedside reassessment, source control evaluation, or local sepsis workflows.
SIRS is the systemic inflammatory response (non-specific — can be from surgery, burns, pancreatitis). Sepsis requires suspected or confirmed infection PLUS organ dysfunction (SOFA ≥ 2).
qSOFA is a bedside screening tool (3 criteria, no labs needed). If qSOFA ≥ 2, perform full SOFA assessment. SOFA requires lab values and is more comprehensive for ICU patients.
Because bundle steps depend on infection source, hemodynamics, comorbidities, access, repeat labs, and the workflow being used locally. This page stays on score interpretation and severity framing rather than turning the calculator into a bedside workflow guide.
Sepsis-3 defines septic shock as sepsis with vasopressor-dependent hypotension and lactate > 2 mmol/L despite fluid resuscitation. This page uses that definition as severity context rather than as a treatment pathway.
Yes. Up to 20% of sepsis patients have normal WBC counts. Bandemia (> 10% bands) or immunosuppression can cause sepsis without leukocytosis. Use qSOFA and SOFA regardless of WBC.
Lactate > 2 mmol/L can add context for hypoperfusion risk and is associated with worse outcomes. Serial lactate trends are often reviewed alongside blood pressure, urine output, and overall clinical trajectory rather than in isolation.