Table 1 Demographics and perioperative details of the patient population^a

Age (years) - mean ± SD

Gender male - number (%)

Weight (kg) - mean ± SD

Body surface area (m²) - mean ± SD

Baseline serum creatinine (mg/dL) - mean ± SD

Estimated creatinine clearance (mL/minute) - mean ± SD

Logistic EuroSCORE - mean ± SD

Acute renal failure risk score [6] - mean ± SD

Diabetes - number (%)

Chronic obstructive pulmonary disease - number (%)

Previous cerebrovascular accident - number (%)

Baseline haemoglobin value (g/dL) - mean ± SD

Reoperation - number (%)

Isolated coronary operation - number (%)

Coronary plus valve operation - number (%)

Valve operation - number (%)

Other operations - number (%)

CPB duration (minutes) - mean ± SD

Nadir temperature (°C) during CPB - mean ± SD

Nadir haemoglobin value (mg/dL) during CPB - mean ± SD

Nadir hematocrit (%) during CPB - mean ± SD

Nadir DO₂ (mL/minute/m²) during CPB - mean ± SD

Peak VCO₂ (mL/minute/m²) during CPB - mean ± SD

Nadir DO₂/VCO₂ ratio during CPB - mean ± SD

Peak serum lactate (mmol/L) during CPB - mean ± SD

Peak postoperative serum creatinine (mg/dL) - mean ± SD

Peak postoperative creatinine change (%)- mean ± SD

Nadir postoperative creatinine clearance (mL/minute) - mean ± SD

Acute kidney injury stage 1 - number (%)

Acute kidney injury stage 2 - number (%)

Any acute kidney injury - number (%)

Packed red blood cells transfusion (U) - median (interquartile range)

ICU length of stay (days) - median (interquartile range)

Postoperative hospital stay (days) - median (interquartile range)