How it's calculated
Six organ systems — respiration, coagulation, liver, cardiovascular, CNS, and renal — are each scored 0-4 based on the worst value in the relevant parameter, and summed for a total of 0-24.
SOFA score and severity
| SOFA score | General severity |
|---|---|
| 0-6 | Low organ dysfunction |
| 7-9 | Moderate organ dysfunction |
| 10-12 | High organ dysfunction |
| 13-24 | Very high organ dysfunction, high mortality risk |
Clinical use
- Used in the ICU to quantify and track the degree of organ dysfunction over time — a rising score suggests worsening critical illness, a falling score suggests improvement.
- Central to the Sepsis-3 definition of sepsis (an acute increase of ≥2 points in SOFA score in the setting of suspected infection).
- Not intended for single-point diagnosis — the trend over serial measurements is more informative than one isolated score.
Frequently asked questions
What does SOFA stand for?
Sequential (originally 'Sepsis-related') Organ Failure Assessment — it scores six organ systems to quantify the degree of dysfunction in critically ill patients.
How is SOFA different from qSOFA?
qSOFA is a simplified 3-criterion bedside screen usable without lab results, meant to quickly flag patients outside the ICU who may be developing sepsis. Full SOFA needs laboratory and physiological data across six organ systems and is used for ongoing severity tracking, typically in the ICU.
Why does SOFA use vasopressor doses for the cardiovascular component?
Because blood pressure alone doesn't capture cardiovascular support — a patient on high-dose vasopressors to maintain a normal MAP is more unwell than the blood pressure number alone suggests, so scoring incorporates vasopressor type and dose. Confirm exact dosing thresholds against your source reference, as conventions vary between institutions.
References
- Vincent JL, et al. The SOFA score to describe organ dysfunction/failure. Intensive Care Med. 1996;22(7):707-710.
- Singer M, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315:801-810.