Risk Factors for Acute Kidney Injury in Aortic Surgery

Objectives: Acute kidney injury (AKI) is still a common complication after aortic surgery with a reported incidence of 19.0 to 29.1%. Thereby, AKI is associated with increased perioperative morbidity and mortality. In this study, we therefore aimed to identify risk factors for the development of an AKI after aortic surgery.

Methods: All patients who underwent aortic surgery between 1998 and 2020 at our center were registered in our dedicated database. Of these, 1,510 patients with complete data on pre- and postoperative renal function could be included into a retrospective analysis. AKI was defined according to the updated Valve Academic Research Consortium (VARC-2) definition. Risk factors for the occurrence of postoperative AKI were identified using multivariate logistic regression analysis.

Result: Mean age was 61.5 ± 14.0 years and 65.3% (n = 986) of the patients were male. The mean EuroSCORE II was 8.5 ± 10.7. Surgical treatment consisted of isolated ascending aortic replacement in 27.7% (n = 419), isolated root replacement in 22.1% (n = 333), hemiarch replacement in 34.8% (n = 525), total arch replacement in 14.6% (n = 220), or descending replacement in 0.9% (n = 13). Frozen elephant trunk technique (FET) was used in 9.0% (n = 136) of the cases.

The overall postoperative AKI rate was 13.0% (n = 197). Using logistic regression analysis, we identified preoperative creatinine clearance (GFR) <50 mL/min (adjusted OR = 4.188, 95% CI: 2.547–6.886; p < 0.001), emergency procedure (adjusted OR = 2.823, 95% CI: 1.613–4.938; p < 0.001), age over 70 years (adjusted OR = 1.630, 95% CI: 1.061–2.502; p = 0.026), and extracorporeal circulation time (ECC) over 210 minutes (adjusted OR = 2.217, 95% CI: 1.378–3.569; p = 0.001) as independent risk factors for postoperative AKI. Furthermore, patients with critical preoperative state (according to EuroSCORE II definition) tended to be at higher risk for AKI (adjusted OR = 1.902, 95% CI: 0.933–3.876; p = 0.077).

Conclusion: In aortic surgery, patients of higher age, with preoperative renal dysfunction, and undergoing emergency treatment or complex procedures with increased ECC time are at high risk of postoperative AKI. Therefore, especially in elderly patients with chronic kidney disease and further comorbidities, aortic surgical techniques with reduced extracorporeal circulation time should be preferred.

Publication History

Article published online:
19 February 2021