Acute kidney injury after cardiac surgery in children

Acute kidney injury (AKI) after cardiac surgery in children remains a common clinical concern. The approaches developed recently and applied in clinical practice have sufficiently helped in clarifying the epidemiology, risk factors and pathophysiology of AKI in paediatric cardiac surgery. Pediatric Risk, Injury, Failure, Loss, End-Stage Renal Disease criteria (pRIFLE), Acute Kidney Injury Network (AKIN) and Kidney Disease: Improving Global Outcomes (KDIGO), which are based on changes in serum creatinine levels and urine output rate, enable the identification and ranking of AKI according to severity. However, the diagnostic strategies for AKI have developed beyond creatinine levels and recommend the use of markers of renal tissue damage. Currently, two markers, neutrophil gelatinase-associated lipocalin and TIMP-2/IGFBP-7 (tissue inhibitor of metalloproteinase 2 and protein that binds insulin-like growth factor-7), can be used for the early diagnosis of AKI in paediatric cardiac surgery. Various risk factors, both renal and extrarenal, can predict AKI after cardiac surgery, among which age, the duration of cardiopulmonary bypass and the need for mechanical ventilation and inotropic support before surgery, are the most significant. Strategies for addressing modifiable risk factors (maintaining appropriate perfusion pressure during cardiopulmonary bypass and avoiding nephrotoxic drugs and fluid overload) will reduce the risk of developing AKI. There has been a significant increase in survival rates due to the introduction of ultrafiltration techniques and the early initiation of renal replacement therapy in the postoperative period. The purpose of this review is to analyse the current literature data on AKI in paediatric cardiac surgery. The review results demonstrate the differences in the incidence of AKI associated with cardiac surgery and the effectiveness of certain methods for prevention and treatment of this complication. Further comprehensive research on the issue of AKI in children, creation of medical electronic databases on patients, minimisation of the influence of possible risk factors and timely prevention and treatment of complications would prevent the development of AKI and reduce the possibility of complication progression to a more severe stage.