This calculator implements SOFA-2, not the legacy SOFA-1

SOFA-2 was published online in October 2025 after a multinational consensus, data-development, and external-validation program involving more than three million adult ICU admissions in nine countries. The JAMA article was corrected in January 2026. It retains six organ systems and a 0–24 total while updating variables, thresholds, and contemporary organ-support definitions.

The original 1996 score is now often called SOFA-1. It became ambiguous or outdated in respiratory, cardiovascular, and kidney support, particularly as high-flow oxygen, modern vasoactive combinations, extracorporeal support, and renal replacement practices changed. SOFA-2 uses new P/F thresholds, explicit advanced-support requirements, summed norepinephrine and epinephrine doses, mechanical support, revised creatinine and urine rules, and current platelet boundaries.

Nearly half of patients in a large reclassification analysis received a different total under SOFA-2 versus SOFA-1. The versions are therefore not interchangeable. A study, EHR, regulatory measure, or local protocol that explicitly requires SOFA-1 must use that exact legacy method, not this calculator.

The six-organ sum

The demonstration selects 1 brain point, 2 respiratory, 2 cardiovascular, 1 liver, 2 kidney, and 1 hemostasis point. The sum is 9. All six domains are above zero, and the highest selected severity tier is two in three domains.

SOFA-2 uses the worst applicable tier in the defined observation window. Within a domain, a patient may meet more than one criterion; choose the highest point value. Do not add creatinine and urine points together, or add pressure and vasoactive points inside the cardiovascular domain. Each organ contributes one score only.

The calculator requires all six selections. Missing values are not automatically normal in bedside care. The validation studies analyzed missingness with prespecified methods, including normal-value imputation; that research approach should not be casually converted into a clinical assumption.

SOFA-2 thresholds summarized

The selections condense the official table. Complex cases require the original footnotes, especially organ-support definitions, drug-dose combinations, sedation, neurologic test alternatives, ceilings of care, and resource-limited substitutions.

SOFA-2, SOFA-1, and qSOFA answer different questions

Sepsis-3 originally operationalized organ dysfunction as an acute SOFA increase of at least two points in a patient with infection. Whether and how a current institution maps that operational definition to SOFA-2 depends on updated clinical and governance decisions. A browser should not silently redefine a syndrome or quality measure.

qSOFA uses respiratory rate at least 22, systolic pressure at most 100, and altered mentation. It does not use P/F ratio, bilirubin, creatinine, platelet count, vasoactive dose, or the 0–24 sum. Current Surviving Sepsis Campaign guidance also recommends other tools over qSOFA as the sole screening method.

Observation windows and serial scoring

SOFA-2 development used first-day ICU data and longitudinal daily assessments. A day score generally uses the worst values in the defined period, but exact start and end times must be fixed. Calendar day, first 24 hours after ICU admission, and study day are not automatically equivalent.

For serial bedside use, the developers describe last observation carried forward as a practical approach when a current domain value is unavailable. Research may use multiple imputation or another prespecified strategy. State the method; otherwise changes in measurement frequency can look like changes in organ dysfunction.

Trend each domain and the total. A stable total can hide improvement in one organ and deterioration in another. Treatment can also change the score: a patient may receive more support while physiology improves. Interpret trajectory with clinical events, treatment goals, and source control, not as a standalone graph.

Organ-support inputs require exact definitions

Respiratory scores 3 and 4 require both a low P/F ratio and qualifying advanced ventilatory support, except ECMO directly qualifies for the 4-point support tier. Oxygen delivery, airway pressure, high-flow systems, noninvasive ventilation, invasive ventilation, and ceilings of treatment must be classified as the authors specify.

Cardiovascular scoring sums norepinephrine and epinephrine doses in mcg/kg/min, then considers other vasopressors or inotropes and mechanical circulatory support. A dose in mcg/min cannot be entered without weight conversion. Temporary support, device type, and simultaneous drugs matter.

Kidney scoring uses the highest of creatinine, weight-based urine output over a defined duration, anuria, or RRT status. Confirm measured weight, collection accuracy, chronic dialysis, and whether RRT criteria are fulfilled even if therapy is unavailable or limited by goals of care.

Do not convert the total into an individual prognosis

In validation, each additional point was associated with higher ICU mortality odds, and score distributions separated groups at a population level. That association does not provide a calibrated probability for a particular person in a particular U.S. hospital. Admission diagnosis, age, chronic disease, frailty, treatment limitations, timing, trajectory, interventions, and local outcomes matter.

The score developers did not seek to replace richer prognostic systems such as APACHE or SAPS. Shared decisions about prognosis require the entire clinical picture, repeated assessment, clinician experience, patient values, and communication of uncertainty.

Never deny ICU admission, transfer, dialysis, ventilation, surgery, medication, or rehabilitation solely because of this total. Use validated institutional processes and ethics safeguards.

Reproducible documentation and quality checks

Record version as “SOFA-2,” the time window, raw source data, support devices, vasoactive doses and units, urine collection interval, neurologic confounders, missing-data method, each domain point, and total. A note that says only “SOFA 9” is ambiguous in 2026 because SOFA-1 and SOFA-2 may differ.

Independently verify unit conversions. Bilirubin may be reported in micromoles per liter outside the United States; creatinine may be micromoles per liter; vasoactive charts may use mcg/min; platelets may use ×10⁹/L, numerically equivalent to ×10³/µL. P/F ratio uses a fraction for FiO2, not a whole percentage.

Automated EHR calculation should be locally validated against official examples, including boundary values, multiple simultaneous supports, missing data, and version labeling. A correct total from incorrect source mapping remains unsafe.

Frequently asked questions

Related U.S. planning context

It does not determine ICU cost, insurance authorization, disability, or medical eligibility.

References

• JAMA: Development and Validation of the SOFA-2 Score
• JAMA Network Open: Rationale and Methodological Approach Underlying SOFA-2
• Sepsis-3 Consensus Definitions
• Society of Critical Care Medicine: Surviving Sepsis Campaign Adult Guidelines

Professional education and scoring audit only. Use corrected official SOFA-2 instructions, local protocol, and clinical judgment.