Methods: Between November 2019 and May 2021, a total of 60 patients (46 males, 14 females; mean age: 62.5±9.6 years; range, 44 to 76 years) who were scheduled for elective coronary artery bypass grafting or valve surgery under cardiopulmonary bypass were included in the study. The patients were divided into two groups as the study group (Group S, n=30) and control group (Group C, n=30). The patients in Group C were treated with standard therapy, while the patients in Group S were treated with goal-directed fluid therapy. The Kidney Disease: Improving Global Outcomes (KDIGO) classification and renal biomarkers were used for the evaluation of acute kidney injury.

Results: Acute kidney injury rates were similar in both groups (30%). Postoperative fluid requirement, intra-, and postoperative erythrocyte suspension requirements were significantly lower in Group S than Group C (p=0.002, p=0.02, and p=0.002, respectively). Cystatin-C was lower in Group S (p<0.002). The kidney injury molecule-1, glomerular filtration rate, and creatinine levels were similar in both groups. The length of hospital stay was longer in Group C than Group S (p<0.001).

Conclusion: Although goal-directed fluid therapy does not change the incidence of acute kidney injury in patients undergoing cardiac surgery, it can significantly decrease Cystatin-C levels. Goal-directed fluid therapy can also decrease fluid and erythrocyte requirements with shorter length of hospital stay.