Total SOFA-2 score = sum of six organ-system scores (0–4 points each; range 0–24). When multiple criteria apply within a domain, use the highest point value.

Organ-system definitions (SOFA-2):

Organ system	0 points	1 point	2 points	3 points	4 points
Brain (neurological)	GCS 15 or able to follow simple motor commands; no drugs needed for delirium.	GCS 13–14 or localises pain, or requires medication to treat delirium.	GCS 9–12.	GCS 6–8 or flexion withdrawal to pain.	GCS 3–5, or extension/no response to pain, or generalised myoclonus.
Respiratory	PaO₂:FiO₂ >300 mmHg (>40 kPa).	PaO₂:FiO₂ ≤300 mmHg (≤40 kPa).	PaO₂:FiO₂ ≤225 mmHg (≤30 kPa).	PaO₂:FiO₂ ≤150 mmHg (≤20 kPa) with advanced ventilatory support (HFNO, CPAP/BiPAP/NIV, invasive or long-term home ventilation).	PaO₂:FiO₂ ≤75 mmHg (≤10 kPa) with advanced ventilatory support or ECMO.
Cardiovascular	MAP ≥70 mmHg, no vasopressor or inotrope.	MAP <70 mmHg, no vasopressor or inotrope.	Low-dose vasopressor: sum of norepinephrine+adrenaline ≤0.2 µg/kg/min, or any dose of another vasopressor or inotrope.	Medium-dose vasopressor: sum of norepinephrine+adrenaline >0.2–≤0.4 µg/kg/min, or low-dose norepinephrine/adrenaline plus another vasopressor or inotrope.	High-dose vasopressor: sum of norepinephrine+adrenaline >0.4 µg/kg/min, or medium-dose norepinephrine/adrenaline plus another vasopressor/inotrope, or mechanical circulatory support (eg VA-ECMO, IABP, LVAD).
Haemostasis (platelets)	>150 ×10³/µL (>150 ×10⁹/L).	101–150 ×10³/µL (101–150 ×10⁹/L).	81–100 ×10³/µL (81–100 ×10⁹/L).	51–80 ×10³/µL (51–80 ×10⁹/L).	≤50 ×10³/µL (≤50 ×10⁹/L).
Liver (total bilirubin)	≤1.20 mg/dL (≤21 µmol/L).	>1.20–≤3.0 mg/dL (>21–≤51 µmol/L).	>3.0–≤6.0 mg/dL (>51–≤103 µmol/L).	>6.0–≤12.0 mg/dL (>103–≤205 µmol/L).	>12.0 mg/dL (>205 µmol/L).
Kidney (creatinine / urine output / RRT)	Serum creatinine ≤1.20 mg/dL (≤110 µmol/L) and no oliguria.	Serum creatinine ≤2.0 mg/dL (≤170 µmol/L), or urine output <0.5 mL/kg/h for 6–12 h.	Serum creatinine ≤3.50 mg/dL (≤300 µmol/L), or urine output <0.5 mL/kg/h for ≥12 h.	Serum creatinine >3.50 mg/dL (>300 µmol/L), or urine output <0.3 mL/kg/h for ≥24 h, or anuria for ≥12 h.	Receiving or meeting criteria for renal replacement therapy (including chronic maintenance therapy).

Sequential Organ Failure Assessment (SOFA)-2 Score