SOFA Score (Sequential Organ Failure Assessment)

Overview

The SOFA score (Sequential Organ Failure Assessment), originally called the Sepsis-related Organ Failure Assessment, was developed by Vincent et al. in 1996 to describe and quantify the degree of organ dysfunction in critically ill patients. It evaluates six organ systems — respiratory, coagulation, hepatic, cardiovascular, central nervous system, and renal — each scored 0 (normal) to 4 (severe dysfunction), yielding a total of 0–24 points.

SOFA gained renewed prominence with the Sepsis-3 consensus in 2016, which defined sepsis as a life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis is now operationally identified by an acute increase in SOFA score of ≥ 2 points, corresponding to an estimated hospital mortality of over 10%. This replaced the former SIRS-based definition.

SOFA can be used as both a static snapshot (absolute score) and a dynamic measure (change over time). Rising SOFA scores during ICU admission are strongly associated with worsening prognosis, while falling scores may reflect treatment response.

Scoring Table

System / Parameter	0	1	2	3	4
Respiration PaO₂/FiO₂ (mmHg)	≥ 400	< 400	< 300	< 200 + resp. support	< 100 + resp. support
Coagulation Platelets (×10³/µL)	≥ 150	< 150	< 100	< 50	< 20
Liver Bilirubin (mg/dL)	< 1.2	1.2 – 1.9	2.0 – 5.9	6.0 – 11.9	≥ 12.0
Cardiovascular MAP / vasopressors	MAP ≥ 70	MAP < 70	Dopa ≤ 5 or Dobu any	Dopa 5–15 or Epi/Norepi ≤ 0.1	Dopa > 15 or Epi/Norepi > 0.1
CNS Glasgow Coma Scale	15	13 – 14	10 – 12	6 – 9	< 6
Renal Creatinine (mg/dL)	< 1.2	1.2 – 1.9	2.0 – 3.4	3.5 – 4.9	≥ 5.0
Renal Urine output (mL/day)	≥ 500	—	—	< 500	< 200

Vasopressor doses in µg/kg/min. For the renal system, the worse of creatinine and urine output scores is used. Respiratory scores 3 and 4 require respiratory support (mechanical ventilation or CPAP).

Interpretation

Total SOFA	Estimated Hospital Mortality
0 – 6	< 10 %
7 – 9	~15 – 20 %
10 – 12	~40 – 50 %
13 – 14	~50 – 60 %
≥ 15	> 80 %

Sepsis-3 criterion: An acute increase in SOFA score of ≥ 2 points from baseline in a patient with suspected infection identifies organ dysfunction and meets the definition of sepsis, with an expected mortality exceeding 10 %. The qSOFA score (≥ 2 of: RR ≥ 22, altered mentation, SBP ≤ 100) can be used outside the ICU to prompt further evaluation.

Literature

Vincent JL, Moreno R, Takala J, et al. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. Intensive Care Med. 1996;22(7):707–710.

Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801–810.

Ferreira FL, Bota DP, Bross A, Mélot C, Vincent JL. Serial evaluation of the SOFA score to predict outcome in critically ill patients. JAMA. 2001;286(14):1754–1758.

Calculate SOFA directly in Scores2Go — free, no account required for the web app.

Open in Scores2Go