老年心脏手术后急性肾损伤可纠正的危险因素分析

Acute kidney injury after cardiac surgery in elderly patients： focus on modifiable risk factors

目的探讨老年心脏手术患者术后急性。肾损伤（AKI）可纠正的危险因素，降低其发生率，改善预后。方法收集广东省人民医院2007年1月至2009年12月年龄≥60岁心脏手术患者的临床资料。以RIFLE标准诊断的AKI为观察终点，术前最后一次血肌酐为基线值。Logistic回归分析确定心脏术后AKI的独立危险因素。结果457例患者入组，313例（68．5％）术后发生AKI。Logistic回归分析显示，男性、年龄〉65岁、高血压、术前估算肾小球滤过率〈60ml／min、术前尿酸〉450ixmol／L（OR2．938，95％可信区间1．633—5．285）、体外循环〉120rain、机械通气时间延长、术后用血管紧张素抑制酶／血管紧张素受体抑制剂和利尿剂是心脏术后AKI的独立影响因素。结论术前尿酸〉450μmol／L是老年心脏手术患者术后AKI可纠正的危险因素。

Objective Acute kidney injury （AKI） is a common complication after cardiac surgery, especially in elderly patients, and related with poor prognosis. Although much advances in therapies of AK1 have been obtained, the prognosis of patients did not improved. In the absence of proven interventions, a reasonable strategy would be to identify modifiable risk factors for AKI. The objective of the present study was to explore modifiable risk factors of acute kidney injury after cardiac surgery with cardiopulmonary bypass in elderly patients. Methods Data from 457 consecutive elderly patients （ age ≥ 60 years old） who underwent cardiac surgery with cardiopulmonary bypass in the Guangdong General Hospital between January 2007 and December 31, 2009 were analyzed in this retrospective research. The primary outcome was AKI according to the serum creatinine criteria of the RIFLE （ renal Risk, Injury, Failure, Loss of renal function and End-stage renal disease） classification as an increase in serum creatinine 〉 50% from baseline to peak value within the first seven postoperative days. The baseline serum ereatinine was defined as the latest serum creatinine before cardiac surgery. Univariate analysis was carried out for patients＇demo- graphics data and multivariate analysis by logistic regression was used to obtain the independent risk factors for AKI. Results Among 457 elderly patients, patients mean age was （65.22 ± 4.17 ） years and they comprised 253 （55.4%） men and 204 （44.6%） women. AKI occurred in 313 （68.5 % ） participants. Compared with patients without postoperative AKI, the media length of intensive care unit was longer in patients with postoperative AKI, 4.0 （ 2.0 - 7.5 ） days versus 2.0 （ 1.0 - 3.0） days, respectively. In logistic regression model, male （odds ratio[ OR31. 894, 95% confidence interval[ CI）1. 136 -3. 157）, age above 65 years （ OR 2.391,95 % CI 1.381 - 4. 142） , hypertension （ OR 2. 286, 95 % CI 1. 249 - 4.184） , estimated glomer- ular filtration rate less than 60 ml/min （ OR 1. 933, 95% CI 1. 111 - 3. 362 ）, preoperative uric acid 〉 450 ~molfL （ OR 2. 938, 95% CI 1. 633 - 5. 285 ） , use of angiotensin converting enzyme inhibitors/angiotensin receptor inhibitors （ ACEI/ ARB） before cardiac surgery （OR 2. 196, 95% CI 1. 283 - 3. 759）, use of ACEI/ARB after surgery （ OR 0. 329, 95% CI 0. 156 -0. 691 ）, use of diuretics （ OR 0. 149, 95% CI 0. 068 -0. 326）, time of eardiopulmonary bypass above 120 min （ OR 5. 228, 95% CI 3. 023 - 9. 041 ） and prolonged mechanical ventilation （ OR 2. 921,95% CI 1. 527 - 5. 586 ） were independent factors of AKI after cardiac surgery with cardiopulmonary bypass. Conclusion Preoperative uric acid above 450μmol/L was a modifiable risk factor of AKI after cardiac surgery with cardiopulmonary bypass in elderly patients. Therapies aimed at mitigating high preoperative uric acid may offer protection against this complication.