IL-6 serum concentration 6 h after weaning from CPB was higher in patients with CSA-AKI, both in terms of absolute values (M = 128.58 (95.53–255.2) ng/mL vs. 86.62 (57.36–115.84) ng/mL in the control group, p = 0.005) and a percentage increase from the initial value (M = 9230 (4453.19–19551.76)% vs. 4189.89 (3001.29–7174.96)% in the control group, p = 0.044)—Figure 1a. This evidence concerns the gene IL6 and acute kidney injury.