Abstract

Background: Acute kidney injury (AKI) is one of the serious complications of cardiac surgery. It is worsened when accompanied by low cardiac output syndrome. Objectives: In this study, we compared kidney function based on the KDIGO criteria in isolated on-pump and off-pump coronary artery bypass graft (CABG) surgery. Methods: In this cohort study, 52 patients with LCOS were enrolled after on-pump (28 patients) and off-pump (24 patients) CABG. In the first six hours after ICU entrance, blood samples were taken for serum creatinine based on routine. For determining AKI after surgery, we used the KDIGO criteria as a primary endpoint. Also, some clinical parameters were recorded before, during, and after surgery. The data were analyzed by SPSS software, version 24, using paired and independent t-test, ANOVA, and Pearson correlation test and non-parametric tests such as Mann-Whitney and Kruskal-Wallis tests at a significance level of P < 0.05. Results: There was no significant difference in age (P = 0.3) and gender (P = 0.57) between the two groups. Among cardiac disease risk factors, only hypertension (P = 0.02) had a significant difference between the two groups, but AKI in patients with hypertension did not show a significant difference (P = 0.09). In paraclinical parameters, serum creatinine showed a significant difference before and after surgery in on-pump (P < 0.001) and off-pump (P = 0.007) groups. Also, this parameter had a significant difference at 6 h, 12 h, 24 h, and 48 h after surgery between the on-pump and on-pump groups. The AKI incidence showed a significant difference between the two groups (P < 0.001). Conclusions: The incidence of AKI was more in on-pump patients than in off-pump patients. Also, a significant difference was observed between their clinical parameters. Thus, to improve the patients' clinical outcomes and lower the health costs, we suggest that patients with a high risk of LCOS be followed up after CABG, especially on-pump CABG.