Fig. 1

Modified sepsis renal angina index. First, the RAI score is calculated as the product of the highest risk and injury strata, resulting in a score between 1 and 40. Next, the sepsis modification is applied as follows: (1) if the patient has an RAI score < 8, they are deemed low risk and not predicted to have D3 severe AKI (sRAI-, green); (2) if the patient has an RAI score ≥ 20, they are deemed high risk and predicted to have D3 severe AKI (sRAI + , red); (3) if the patient has an intermediate RAI score (8 to < 20), platelet count is considered for further risk stratification. Patients with platelet count ≥ 150 × 10³/µL are deemed low risk and not predicted to have D3 severe AKI (sRAI-, green), while those with platelet count < 150 × 10³/µL are deemed high risk and predicted to have D3 severe AKI (sRAI + , red). SCr > Baseline: degree of serum creatinine elevation above baseline on Day 1 of septic shock; %FB: cumulative percent fluid balance on Day 1 of septic shock; sRAI: modified sepsis renal angina index; RAI: Renal angina index; D3 severe AKI: severe acute kidney injury on Day 3 of septic shock