Figure 2:

Serial change in serum creatinine (mg/dl) and urine output (ml/kg/h) (upper graph) and change in plasma lactate concentration (lower graph) at preoperative, surgery, intensive care unit admission and postoperative days 1–3. Serum creatinine concentration rose to a peak level during the first 24 h after surgery, whereas the urine output declined through the first 12 h after surgery and recovered after 18 h after surgery. Plasma lactate increased to over 4 mmol/l during HFRCP and gradually decreased to baseline levels during the first 24 h after surgery. Values are expressed as median with interquartile range. *1: cardiopulmonary bypass cooling; *2: HFRCP; *3: rewarming; *4: termination of cardiopulmonary bypass. HFRCP: high-flow regional cerebral perfusion; op: operation.