Risk factors of perioperative acute kidney injury in elderly patients: a single-center retrospective study

Purpose The elderly are vulnerable to perioperative acute kidney injury. The aim of this study was to determine the risk factors that associated with acute kidney injury among elderly patients. Methods Clinical data of elderly patients (> 65 years) who underwent noncardiac, nonrenal surgery between Dec 1 2009 and July 1 2016 were collected for this single-centered historical cohort study. Univariate and multivariate analyses were conducted to explore the risk factors that contribute to acute kidney injury, which was defined as a serum creatinine increase >0.3 mg/dL within 48 h or 1.5 times increase in serum creatinine within 7 days after surgery. Results 7775 patients were eligible for the final analysis, among which 511 (6.57%) patients developed acute kidney injury. We observed 21 risk factors being associated with perioperative acute kidney injury, with the most important disposing factors being history of kidney disease (adjusted OR= 2.94, 95% CI 2.25-3.84), operation time > 180 min (aOR = 2.93, 95% CI 2.04-4.24), preoperative eGFR [15, 30) (aOR =2.43, 95% CI 1.29-4.45), and protective factor being intraoperative use of sufentanil (aOR = 0.35, 95% CI 0.23-0.54). Conclusion This study determined risk factors for perioperative acute kidney injury among the elderly in the Second Xiangya Hospital and visualized the risk factors using nomogram and Excel calculator, which may provide some clues to further investigations. Overall, the prevalence of AKI among this large cohort is 6.57%.