Cardiac Surgery-associated Acute Kidney Injury in Patients with Preserved Baseline Renal Function

ABSTRACT Introduction: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a powerful predictor of perioperative outcomes. We evaluated the burden of CSA-AKI in patients with preserved baseline renal function. Methods: The data of 2,162 adult patients who underwent cardiac surgery from January 2005 to December 2020 were analyzed. Logistic regression models were used to determine predictors of CSA-AKI and their associations with hospital mortality up to 30 days. Results: The prevalence of acute kidney injury was 43.0%, and 2.0% of patients required renal replacement therapy. Hospital mortality rate was 5.6% (non-acute kidney injury = 2.0% vs. CSA-AKI = 10.4%, P<0.001), and any degree of CSA-AKI was associated with a significant increase in death rates (stage 1 = 4.3%, stage 2 = 23.9%, stage 3 = 59.7%). Multivariable logistic regression analysis identified age, obesity, left ventricular dysfunction, previous cardiac surgery, and cardiopulmonary bypass duration as predictors of CSA-AKI. Moreover, CSA-AKI was confirmed as independent predictor of hospital mortality for stage 1 (odds ratio, 2.02; 95% confidence interval, 1.16 to 3.51; P=0.013), stage 2 (odds ratio, 9.18; 95% confidence interval, 4.54 to 18.58; P<0.001), and stage 3 (odds ratio, 37.72; 95% confidence interval, 18.87 to 75.40; P<0.001) patients. Conclusion: Age, obesity, left ventricular dysfunction, previous cardiac surgery, and cardiopulmonary bypass duration are independent predictors of CSA-AKI in patients with preserved baseline renal function. The development of CSA-AKI is significantly associated with worse outcomes, and there is a dose-response relationship between acute kidney injury stages and hospital mortality.

摘要
引言：心脏手术相关急性肾损伤（Cardiac surgery-associated acute kidney injury, CSA-AKI）是围手术期预后的强预测因子。本研究旨在评估基线肾功能正常患者的CSA-AKI疾病负担。
方法：分析2005年1月至2020年12月期间接受心脏手术的2162例成年患者的临床资料。采用Logistic回归模型确定CSA-AKI的预测因子及其与术后30天内住院死亡率的关联。
结果：急性肾损伤的总体患病率为43.0%，其中2.0%的患者需接受肾脏替代治疗。总体住院死亡率为5.6%（非急性肾损伤组为2.0%，CSA-AKI组为10.4%，P<0.001）；任意程度的CSA-AKI均与死亡率显著升高相关（1期为4.3%，2期为23.9%，3期为59.7%）。多因素Logistic回归分析显示，年龄、肥胖、左心室功能不全、既往心脏手术史及体外循环时长为CSA-AKI的独立预测因子。此外，针对各分期患者，CSA-AKI均被证实为住院死亡率的独立预测因子：1期患者的比值比为2.02（95%置信区间：1.16~3.51，P=0.013），2期为9.18（95%置信区间：4.54~18.58，P<0.001），3期为37.72（95%置信区间：18.87~75.40，P<0.001）。
结论：在基线肾功能正常的患者中，年龄、肥胖、左心室功能不全、既往心脏手术史及体外循环时长是CSA-AKI的独立预测因子。CSA-AKI的发生与不良预后显著相关，且急性肾损伤分期与住院死亡率存在剂量-反应关系。