Association between transfusion of blood products and acute kidney injury following cardiac surgery

Background: Acute kidney injury (AKI) is a serious complication following cardiac surgery associated with increased mortality. Red blood cell transfusion enhances the risk of developing AKI. However, the impact of other blood products on AKI is virtually unexplored. The aim of this study was to explore if transfusion of red blood cells, fresh frozen plasma and platelets alone or in combination were associated with postoperative AKI. Methods: Patients undergoing elective on-pump cardiac surgery were included (n = 1960) between 2012 to 2014. Transfusion data were collected intraoperatively and until the first postoperative day. AKI was classified according to the KDIGO criteria. Data were analysed using univariate and stepwise multiple logistic regression with adjustment for clinical risk factors and complementary blood products. Results: AKI was observed in 542 patients (27.7%). In univariate analysis and following adjustment for clinical risk factors, administration of red blood cells, freshfrozen plasma and platelets were all independently associated with KDIGO stage 2-3. Following additional adjustment for complementary blood products, only red blood cell transfusion remained significantly associated with AKI. A dose-dependent association between volume of red blood cells and degree of AKI severity was observed. Conclusion: Transfusion of all blood products in a dose-dependent manner increased the risk for AKI. However, in multivariate analysis combining all blood products, only red blood cell transfusion remained significantly associated with AKI development.