Predictors of Acute Kidney Injury Development After Cardiac Surgery Under Cardiopulmonary Bypass

Abstract

Purpose: To identify the incidence of acute kidney injury in the early postoperative period in cardiac surgery patients operated under cardiopulmonary bypass, and to determine possible risk predictors of its development. Material and methods: Analysis of 103 case histories of patients was performed; 39 of these patients developed acute kidney injury of stages 1-3. Clinical and clinical laboratory data were collected and analyzed at the preoperative and intraoperative stages. Results: A total of 37.9% of patients developed signs of acute kidney injury. This group of patients tended to be older, and was initially characterized by statistically significantly higher levels of creatinine and cystatin C and reduced levels of total serum protein and hemoglobin. Analysis of the possible predictors of acute kidney injury revealed that at the preoperative stage, the level of cystatin C had the highest association with the development of kidney damage in the early postoperative period (OR 15.828, 95% CI 1.66-150.54, p=0.016) and exceeded the traditional marker – serum creatinine. Among intraoperative factors, the duration of cardiopulmonary bypass (OR 1.015, 95% CI 1.006-1.023, p=0.001) and severity of intraoperative hemolysis (OR 1.017, 95% CI 1.004-1.030, p=0.008) demonstrated the greatest association with kidney damage. Сonclusion: It has been found that the risk of acute kidney injury in patients with preexisting renal failure is two times higher than in patients with intact renal function. The most significant intraoperative modifiable factors affecting postoperative renal injury are the duration of cardiopulmonary bypass and the level of hemolysis.