Question 1

What does the SOFA score measure?

Accepted Answer

SOFA grades dysfunction in six organ systems, each from 0 (normal) to 4 (most abnormal), for a total of 0–24: respiration (PaO₂/FiO₂ ratio), coagulation (platelet count), liver (bilirubin), cardiovascular (mean arterial pressure or the dose of vasopressor required), CNS (Glasgow Coma Scale), and renal (creatinine or urine output). It describes the breadth and severity of organ dysfunction rather than diagnosing any single condition.

Question 2

How is the SOFA score used in the Sepsis-3 definition?

Accepted Answer

Under Sepsis-3 (2016), sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection, operationalized as an acute increase in SOFA of ≥2 points from baseline in a patient with suspected infection. Baseline is assumed to be 0 if there is no known pre-existing organ dysfunction. A ≥2-point rise is associated with in-hospital mortality greater than 10%. This replaced the older SIRS-based definition of sepsis.

Question 3

What is the difference between sepsis and septic shock under Sepsis-3?

Accepted Answer

Sepsis is infection plus a ≥2-point SOFA rise (organ dysfunction). Septic shock is a subset with circulatory and metabolic derangement severe enough to substantially increase mortality, identified clinically by a vasopressor requirement to maintain MAP ≥65 mmHg together with a serum lactate >2 mmol/L despite adequate fluid resuscitation. Septic shock carries a markedly higher mortality (>40% in the consensus cohorts) than sepsis without shock.

Question 4

How does the SOFA score relate to mortality?

Accepted Answer

Both the initial and the highest (peak) SOFA scores, and a rising score over time, correlate with ICU mortality — which is why SOFA is often trended daily. Approximate bands run from under 10% at low scores to over 80% at the highest, but exact figures vary by cohort, case mix, and era, so the numbers are best used as relative gradations rather than precise predictions for an individual.

Question 5

What is the difference between SOFA and qSOFA?

Accepted Answer

SOFA is the full, laboratory-based organ-dysfunction score used mainly in the ICU. qSOFA is a labs-free three-variable bedside prompt (respiratory rate ≥22, altered mentation, systolic BP ≤100) meant to flag risk in suspected infection outside the ICU — not a substitute for SOFA. A positive qSOFA should prompt assessment with the full SOFA score; see the qSOFA calculator for its current, narrowed role.

Question 6

How often is the SOFA score calculated?

Accepted Answer

In the ICU, SOFA is typically scored daily (and the worst value in each 24-hour period is often recorded) to track the trajectory of organ dysfunction. A rising score signals worsening organ failure and rising mortality risk, while a falling score suggests recovery; the trend over time is generally more informative than any single value.

SOFA Score	Estimated Mortality
0 – 6	< 10%
7 – 9	15–20%
10 – 12	40–50%
≥ 13	> 80%

SOFA Score Calculator

Organ System Scores

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