Left axis: The mean urinary oxygen partial pressure with 95% CI during the two intraoperative time periods (cardiopulmonary bypass and after cardiopulmonary bypass) for the patients who developed acute kidney injury (AKI; orange solid squares) and those who did not (blue solid circles). Right axis: Daily serum creatinine measurements with 95% CI from baseline until postoperative day 7 for patients who developed AKI (orange open squares) and those who did not (blue open circles). P values from comparisons at specific time points for the AKI and non-AKI groups are reported if less than 0.05. P values for serum creatinine were adjusted for multiple comparisons using Hommel’s procedure.