A diagnosis of a renal injury by early biomarkers in patients exposed to cardiopulmonary bypass during cardiac surgery

We prospectively studied renal function in 158 patients scheduled for elective cardiac surgery with the use of cardiopulmonary bypass (CPB). The patients involved in this study had normal renal function as well as normal function of the left ventricle. The results of the study showed a statistically significant increase of early markers of renal injury Alpha-1-Microglobulin (A1M) and Neutrophil Gelatinase-Associated Lipocalin (NGAL), which were being traced in the patients' urine 5 hours and 24 hours after CPB. In contrast with the aforementioned early markers, the so-called "classical" markers of renal injury - serum urea and creatinine - did not show a statistical significance of value increase after CPB. Using early factors of renal injury A1M and NGAL, the study managed to show slight, subclinical injuries of the proximal renal tubules after CPB and cardiac surgeries. The value of these factors lies in their early and precise detection of renal injury, which is a significant clinical parameter for monitoring renal function, especially after cardiac surgery with the use of CPB.