Risk assessment of acute kidney injury following cardiopulmonary bypass

Abstract

Background: Acute kidney injury (AKI) is a frequent and serious complication of cardiac surgery, associated with a high incidence of morbidity and mortality. Although the RIFLE criteria serve as a prominent tool to identify patients at high risk of AKI, an optimized diagnosis model in clinical practice is desired.Methods: Based on the SOP-criteria, 365 patients (10%) developed AKI following surgery and were subjected to RRT. In contrast, the incidence of AKI, defined according to the RIFLE criteria, was only 7% (n=251 patients). Prominent risk factors identified by SOP were patients’ sex, valve and combined valve and bypass surgery, deep hypothermia, use of intra-aortic balloon pump (IABP) and previous coronary interventions. Ischemia, reperfusion, blood loss and surgery time also served as significant risk factors for patient evaluated by SOP.Results: Risk assessment by RIFLE differed in as much as most patients with normothermia and those receiving only cardiovascular bypass developed AKI. However, patients’ sex and valve surgery did not serve as a risk factor.Conclusion: Evaluation of patients by the RIFLE versus SOP criteria yielded different results with more AKI patients detected by SOP. Based on the present data, it is concluded that patients may not prone to AKI when surgery and ischemia time will be kept short, when blood loss is mitigated to a minimum and when surgery is performed under non-hypothermic conditions

Acute Kidney Injury following Cardiopulmonary Bypass: A Challenging Picture

“…Time on CPB. Time on CPB was associated with the risk of developing AKI requiring dialysis [41,[68][69][70][71] In one study, after adjusting for confounders, the association between the time on CPB and AKI requiring dialysis lost its statistical significance [71]. Thus, an accurate risk assessment might be more important than the time on CPB in predicting the occurrence of AKI requiring dialysis.…”