Perioperative Renoprotection: Clinical Implications

Acute kidney injury (AKI) remains a common complication in the perioperative setting affecting patients' short- and long-term outcome. Because therapeutic options are restricted to the use of renal replacement therapy, preventive strategies have become increasingly important. Several substances have been investigated for preventing AKI with limited to no effects. The lacking effectiveness of all these therapies might be caused by the fact that the therapy was started too late. In all the studies, therapy was initiated once a reduced kidney function occurred. In contrast to the classical functional biomarkers, new renal biomarkers allow to identify kidney damage without a loss of function thus enabling the implementation of preventive measures at the stage of renal stress. The most promising preventive strategy to date seems to implement a bundle of supportive measures in patients at high risk for AKI as recommended by the Kidney Disease: Improving Global Outcomes (KDIGO) group. This strategy includes the avoidance of nephrotoxic drugs and contrast agents, avoidance of hyperglycemia, optimization of perfusion pressure and hemodynamics with consideration of a functional hemodynamic monitoring, and close monitoring of renal function in patients at high risk for AKI. This review discusses new renal biomarkers for identifying kidney damage, the background of why the different measures of the KDIGO bundle might positively affect renal function and prevent the development of AKI, and presents the current literature of biomarker-based approaches in AKI.