术前血清尿酸水平对老年患者心脏手术后急性肾损伤的影响

Impact of pre-operative uric acid on acute kidney injury after cardiac surgery in elderly patients

目的 探讨术前血清尿酸水平对老年患者心脏手术后急性肾损伤（AKI）的影响.方法 回顾性分析广东省人民医院2005年1月至2011年5月行体外循环心脏手术的936例老年（≥60岁）患者的临床资料.以术前末次血清肌酐为基线值,采用RIFLE标准诊断AKI.按尿酸水平的三分位数进行分组,A组为男性≤384.65 μmol/L,女性≤354.00 μmol/L,共312例;B组为男性384.66-476.99 μmol/L,女性354.01 -437.96μrnol/L,共311例;C组为男性≥477.00 μmol/L,女性≥437.97μmol/L,共313例.通过多因素logistic回归分析心脏手术后发生AKI的危险因素.结果 发生AKI的患者共576例（61.5％）,AKI患者和非AKI患者的血清尿酸水平分别为（436.6 119.1）μmol/L和（398.0±107.2）μmol/L,差异有统计学意义（P＜0.001）.发生AKI的患者A组共175例（56.1％）,B组共175例（56.3％）,C组共226例（72.2％）,3组间的AKI发生率差异有统计学意义（P ＜0.001）.多因素logistic回归分析显示,校正年龄、性别、合并症（高血压、糖尿病、脑血管疾病、慢性阻塞性肺疾病）、既往心脏手术史、估算肾小球滤过率＜60 ml·min^-1·1.73 m^-2、心功能≥3级（NYHA分级）、尿蛋白阳性、联合冠状动脉旁路移植术和瓣膜手术、体外循环时间、主动脉阻断时间、术前用药（血管紧张素转换酶抑制剂或血管紧张素Ⅱ受体拮抗剂、调脂药）、术后早期用药（血管紧张素转换酶抑制剂或血管紧张素Ⅱ受体拮抗剂、利尿剂、地高辛）、术后早期中心静脉压后,与A组比较C组术后发生AKI的风险增加（OR：1.897,95％CI：1.270 -2.833,P=0.002）.结论 术前较高的血清尿酸水平可增加老年患者心脏手术后发生AKI的风险.

Objective To investigate the impact of pre-operative uric acid on acute kidney injury （AKI） after cardiac surgery in elderly patients.Methods Clinical data were collected from 936 elderly patients （age ≥ 60 years）undergoing cardiac surgery with cardiopulmonary bypass in Guangdong General Hospital between January 2005 and May 2011.The baseline serum creatinine was defined as the latest serum creatinine before surgery,and AKI was diagnosed according to RIFLE criteria.Patients were divided into three groups according to the sex-specific cutoff values of serum uric acid tertiles （group A：≤ 384.65 μmol/L in men,and ≤354.00 μmol/L in women; group B：384.66-476.99 μmol/L in men and 354.01-437.96μmol/L in women; group C：≥ 477.00 μmol/L in men and ≥ 437.97 μmol/L inwomen）.Multivariate logistic regression analysis was used to analyze the independent risk factors for AKI.Results Among 936 elderly patients,576 cases （61.5%） developed AKI.Mean uric acid concentration was higher in AKI patients than in Non-AKI patients （（436.6 ± 119.1） μmol/L vs.（398.0 ± 107.2） μmol/L,P 〈0.001）.The incidence of AKI was 56.1% （175/312） in group A,56.3% （175/311） in group B,72.2% （226/313） in group C （P 〈 0.001）.Multiple logistic regression analysis showed that,after adjusted for age,gender,co-morbidities （hypertension,diabetes mellitus,cerebrovascular disease,chronic obstructive pulmonary disease）,previous cardiac surgery,eGFR 〈 60 ml · min^-1 · 1.73 m^-2,heart function ≥ 3（NYHA）,positive urine protein,combination of coronary artery bypass grafting and valvular surgery,cardiopulmonary bypass operation time,aortic cross-clamping time,pre-operative angiotensin converting enzyme inhibitor or angiotensin Ⅱ receptor blockers and lipid-lowering drugs use,early postoperative angiotensin converting enzyme inhibitor or angiotensin Ⅱ receptor blockers,diuretics and digoxin use,postoperation central venous pressure,risk of post operative AKI was significantly higher in group C than in group A（OR：1.897,95% CI：1.270-2.833,P =0.002）.Conclusion Pre-operative elevated uric acid is an independent risk factor of AKI after cardiac surgery in elderly patients.