acute kidney injury in MIMIC

we only included the data from the first ICU admission of each adult patients. And we excluded patients if who 1) stayed in ICU less than 24 hours, 2) missed key data (serum creatinine, urine output, neutrophil, lymphocyte or platelet) and 3) without AKI. The identification of AKI was based on the Kidney Disease: Improving Global Outcomes (KDIGO) guideline: urine output less than 0.5 ml/kg/hour for 6 hours, or serum creatinine (SCr) increases ≥0.3 mg/dl within 48 hours or increases ≥1.5 times baseline value within 7 days. Demographic information included age, sex, ethnicity, care unit and body mass index (BMI). Laboratory measurements included leukocyte, neutrophil, lymphocyte, erythrocyte, hemoglobin (Hb), red cell distribution width (RDW), platelet, blood glucose, SCr, blood urea nitrogen (BUN), serum sodium, serum potassium, serum chloride, serum pH, bicarbonate, partial pressure of oxygen (PO2) and partial pressure of carbon dioxide (PCO2) over the first 24 hours into the ICU. And Sequential Organ Failure Assessment (SOFA) score, Simplified Acute Physiology Score II (SAPSII) and comorbidity were also extracted over the first 24 hours.