Preoperative serum cystatin C combined with dipstick proteinuria predicts acute kidney injury after cardiac surgery

Background: Acute kidney injury (AKI) is common following cardiac surgery and is associated with poor outcomes. However, the detection of those preoperative patients who will develop AKI is still difficult. In this study, we compared serum cystatin C combined with dipstick proteinuria as early markers to predict AKI available before surgery. Methods: We prospectively followed 616 patients undergoing cardiac surgery and identified 179 that developed AKI, defined as an increase in serum creatinine (SCr) of ≥?0.3?mg/dL or ≥?50% increase in creatinine level. Preoperative values for cystatin C were categorized into quartiles. We defined proteinuria, measured with a dipstick, as mild (trace to 1+) or heavy (2?+?to 4+). Univariate as well as multivariate regression was performed. Cystatin C combined with dipstick proteinuria before surgery was assessed for its' predictive value of AKI using receiver operating characteristic (ROC) curves. Results: The final cohort consisted of 616 patients aged 60.7?±?13.2 years, and baseline SCr was 75.8?±?26.4?μmol/L, estimated glomerular filtration rate (eGFR) 96.3?±?29.0?mL/min/1.73?m² and cystatin C 1.05?±?0.33?mg/L. Patients in higher cystatin C quartiles were older (p?p?=?0.021), hyperuricemia (p?p?p?=?0.002). Those with heavy proteinuria were more often to have diabetes mellitus (p?=?0.010), hyperuricemia (p?=?0.043), worse cardiac function (p?p?p?p?p?p?p?p?Conclusion: These data suggest that preoperative serum cystatin C combined with dipstick proteinuria may improve prediction of AKI among patients undergoing cardiac surgery.     

术前高敏C反应蛋白水平与成人心脏手术后急性肾损伤的相关性

目的 分析术前高敏C反应蛋白（hs-CRP）水平与成人心脏手术后急性肾损伤（AKI）的相关性。
方法 本研究为回顾性病例-对照研究。收集2017年1月至2018年12月行开放心脏手术的成年患者病历资料。根据改善全球肾脏病预后组织（KDIGO）标准判断AKI。采用多因素Logistic回归分析评估术前hs-CRP水平>3 mg/L与术后AKI的相关性。
结果 本研究共纳入患者17 339例,术后有5 231例（30.1%）发生AKI。术前hs-CRP>3 mg/L的患者有4 350例（25.1%）。单因素分析显示,AKI患者术前存在hs-CRP>3 mg/L的比例明显高于非AKI患者（30.5% vs 24.8%,P<0.001）。在校正了性别、年龄、既往史、术前心功能、术前肾功能、术中输血情况等因素后,术前hs-CRP>3 mg/L是成人心脏术后发生AKI的独立危险因素（OR=1.145, 95%CI 1.052～1.246,P=0.002）。
结论 术前hs-CRP水平>3 mg/L会增加心脏术后AKI的发生风险。     

Anemia-associated acute kidney injury after cardiac surgery with cardiopulmonary bypass

Objective To investigate the incidence and to evaluate the risk factors of acute kidney injury (AKI) following cardiac surgery with cardiopulmonary bypass (CPB) at general hospitals. Methods A retrospective cohort database study was conducted, involving 233 patients who were scheduled to heart valve surgery or coronary artery bypass grafting (CABG) with CPB technique. Logistic regression was used to screen out the risk factors of AKI after the surgery. Results The study population, with an average age of 57±12 years (age 21 to 83) were investigated, there were 54(23.2%) diabetes patients, 105 (45.1%) hypertension patients, 21 (9%) chronic kidney disease (CKD) patients, and 51 (21.9%) anemia patients. Overall incidence of AKI was 32.2%. The Analysis Result indicates that preoperative CKD, anemia, hypoalbuminemia, left ventricular ejection fraction, intraoperative aortic block time, minimum mean arterial pressure, perioperative infection, and application of vancomycin are risk factors associated with postoperative AKI. Multiariable Logistic regression suggests that basic CKD (OR=9.498, P=0.001), anemia (OR=3.150, P=0.021), the LVEF before surgery (OR=1.733, P=0.045), intraoperative aortic block time (OR=2.227, P=0.026), and white blood cell (OR=3.357, P=0.032) were the independent risk factors of AKI. Conclusions AKI is a common complication following cardiac surgery with CPB. The patients with preoperative renal insufficiency, anemia, long intraoperative aortic block time and higher perioperative white blood cell count are subjected to a higher incidence of AKI. Alleviating patients’ anemia and reducing artery block of extracorporeal circulation time therefore might be potential means to mitigate the risks of AKI after cardiac surgery.     

Metabonomics of acute kidney injury in children after cardiac surgery

Acute kidney injury (AKI) is a major complication in children who undergo cardiopulmonary bypass surgery. We performed metabonomic analyses of urine samples obtained from 40 children that underwent cardiac surgery for correction of congenital cardiac defects. Serial urine samples were obtained from each patient prior to surgery and at 4 h and 12 h after surgery. AKI, defined as a 50% or greater rise in baseline level of serum creatinine, was noted in 21 children at 48–72 h after cardiac surgery. The principal component analysis of liquid chromatography/mass spectrometry (LC/MS) negative ionization data of the urine samples obtained 4 h and 12 h after surgery from patients who develop AKI clustered away from patients who did not develop AKI. The LC/MS peak with mass-to-charge ratio (m/z) 261.01 and retention time (t_R) 4.92 min was further analyzed by tandem mass spectrometry (MS/MS) and identified as homovanillic acid sulfate (HVA-SO₄), a dopamine metabolite. By MS single-reaction monitoring, the sensitivity was 0.90 and specificity was 0.95 for a cut-off value of 24 ng/μl for HVA-SO₄ at 12 h after surgery. We concluded that urinary HVA-SO₄ represents a novel, sensitive, and predictive early biomarker of AKI after pediatric cardiac surgery.     

Platelet-leukocyte aggregates – a predictor for acute kidney injury after cardiac surgery

BackgroundAcute kidney injury (AKI) is one of the most common complications after cardiac surgery. However, effective biomarker used for early diagnosis of AKI has not been identified. Platelet-leukocyte aggregates (PLAs) participate in inflammation and coagulation, leading to vascular lesions and tissue destruction. We designed a prospective study to assess whether PLAs can serve as a good biomarker for early diagnosis of AKI after cardiac surgery.MethodsPatients with rheumatic heart disease scheduled to undergo valve replacement surgery were enrolled. Blood samples were collected at five timepoints as follows: (a) At baseline. (b) At the end of extracorporeal circulation. (c) Arrival at intensive care unit (ICU). (d) Four-hours after the admission to ICU. (e) Twenty hours after the admission to ICU. After collection, the samples were immediately used for PLAs measurement by flow cytometry.ResultsA total of 244 patients were registered, and 15 of them were diagnosed with AKI according to the serum creatinine of KDIGO guidelines. The PLAs levels in AKI group were significantly increased 20 h after surgery (two-way repeated measure analysis of variance, p < 0.01) compared with that at baseline. Patients whose preoperative PLAs were higher than 6.8% showed increased risk of developing AKI (multivariate logistic regression; p = 0.01; adjusted odds ratio, 1.05; 95% confidence interval, 1.01–1.09).ConclusionPLAs is an independent risk factor for AKI after valve replacement among patients with rheumatic heart disease.     

心肺转流下心脏瓣膜术后急性肾损伤的危险因素分析

目的探讨成人心肺转流(cardiopulmonary bypass,CPB)下心脏瓣膜手术后急性肾损伤(acute kidney injury,AKI)的危险因素。方法回顾性分析1 349例心脏瓣膜手术患者的临床资料,采用多因素Logistic回归分析心脏瓣膜术后AKI的危险因素。结果 1 349例心脏瓣膜手术患者AKI发生率为28.4%,多因素Logistic回归分析显示,每增加1岁(OR=1.05,95%CI 1.03~1.06,P0.001)、糖尿病史(OR=2.11,95%CI 1.22~3.68,P=0.008)、贫血(OR=1.50,95%CI1.05~2.21,P=0.026)、术前血清肌酐(Scr)值每增加1mg/dl(OR=1.01,95%CI 1.01~1.02,P=0.001)、手术时间每增加1h(OR=1.28,95%CI 1.15~1.41,P0.001)、术中输注血浆(OR=1.50,95%CI 1.14~1.97,P=0.004)是心脏瓣膜术后发生AKI的独立危险因素。结论心肺转流下心脏瓣膜术后急性肾损伤的独立危险因素是高龄、糖尿病史、贫血、术前肌酐高、手术时间长以及术中输注血浆。     

体外循环患者术后发生急性肾损伤的风险评估

目的 探讨体外循环心脏停搏手术后并发急性肾损伤（acute kidney injury,AKI）的肾脏危险因素以及不同肾小球滤过率估测值（estimated glomerular filtration rate,eGFR）水平与AKI发生率之间的关系.方法 回顾性分析793例行体外循环心脏手术成人患者的临床资料,分别统计患者术前及术后7d内血肌酐（SCr）值、术后尿量,评价有无AKI的发生.采用回归分析等统计学方法研究SCr、尿素氮（BUN）、尿酸（UA）、血尿、蛋白尿,肾脏影像学异常（包括B超、CT及ECT）等因素与AKI之间的关系.采用简化MDRD公式计算eGFR,探讨不同水平的eGFR与AKI发生率之间的关系.结果 体外循环心脏停搏术后7d内并发AKI者136例（占17.1％00）;术前蛋白尿、肾脏体积缩小或弥漫性改变,肾积水,血肌酐、尿素氮浓度增高,eGFR≤90 ml· min^-1·（1.73 m^2）^-1等因素与AKI的发生明显相关（P＜0.01）;eGFR≤90 ml·min^-1·（1.73 m^2）^-1时,术后AKI发生率升高,且二者之间呈负相关.Logistic回归分析结果显示术前蛋白尿,肾脏体积缩小或弥漫性改变,血肌酐浓度增高为术后并发AKI的独立危险因素.结论 体外循环心脏停搏术前肾脏损伤可导致术后并发AKI,临床工作中必须谨慎评估风险和认真防治.     

白细胞介素-18早期诊断冠脉搭桥术后急性肾损伤的研究

目的 研究白细胞介素-18 (IL-18)与冠脉搭桥手术后急性肾损伤(AKI)的关系.方法 选择冠状动脉硬化性心脏病行冠脉搭桥手术的患者80例,根据AKI诊断标准,分为AKI组和非AKI组.分别留取术前及术后2、4、6、8、12、24 h等不同时间点的血液和尿液标本,测定标本中血清肌酐(Scr)、血液及尿液中IL-18水平.运用ROC曲线及曲线下面积评价尿液及血液的IL-18对AKI的敏感性及特异性.结果 80例患者共有13例发生AKI,发病率为16.25％,AKI组Scr升高峰值出现在24 ～ 48 h内.血、尿IL-18峰值均出现在术后4h,ROC曲线显示术后2h血及尿IL-18的AUC均＞0.8.Logistic回归分析表明术后2h血、尿IL-18是冠脉搭桥手术后AKI发生的有效预测指标.结论 冠脉搭桥手术后血液及尿液IL-18可作为冠脉搭桥术后AKI早期诊断生物标志物.     

The prognostic value of using the duration of acute kidney injury in cardiac surgery: an example using two antifibrinolytics

Previously, we reported that the addition of duration to the Acute Kidney Injury Network (AKIN) definition of acute kidney injury (AKI) is a marker for more severe kidney injury and predicts long-term mortality. We aimed to evaluate an example of the utility of adding AKI duration to the AKIN definition by comparing the historical use of aprotinin with Amicar. In a single-center observational study, we followed 4987 consecutive patients undergoing cardiac surgery between 2002 and 2007 for postsurgery AKI. Patients with a history of hemodialysis were excluded. Duration of AKI was calculated by the number of days AKI was present as defined by a > or = 0.3 (mg/dL) or a > or = 50% increase in serum creatinine from baseline or new onset of acute dialysis. Kaplan-Meier and Cox's proportional hazard modeling was conducted to evaluate 5-year mortality. Fifty-three percent of patients received Amicar (n = 2333) and 47% received high-dose aprotinin (n = 2093). Patients receiving aprotinin had evidence of more advanced disease and comorbidity and were more likely to develop AKI and have longer durations of AKI than Amicar (p < .001): 7.0 +/- 11.5 vs. 3.8 +/- 6.0 days (p < .001). Nearest-neighbor propensity matching demonstrated aprotinin had significantly worse 5-year mortality compared with Amicar (relative risk [RR] = 2.09, 95% confidence interval [CI] = 1.65-2.65). AKI duration added to the AKIN definition of AKI may provide the necessary sensitivity and specificity for evaluating renal outcomes in clinical trials.     

Risk factor for acute kidney injury in patients with chronic kidney disease receiving valve surgery with cardiopulmonary bypass

IntroductionAcute kidney injury (AKI) after cardiopulmonary bypass (CPB) in patients with pre-existing impaired renal function carries deleterious outcomes but is not frequently evaluated. The optimal CPB strategy for preventing AKI in this vulnerable patient group is still controversial.MethodsA total of 156 patients with preoperative estimated glomerular filtration rate (e-GFR) <30 ml/min but not on chronic dialysis receiving valve operation under CPB were included in the present study. Postoperative AKI was defined as KDIGO (Kidney Disease Improving Global Outcomes) stage 3. Hospital mortality and two-year renal function evolution were compared between patients with postoperative AKI and those without AKI. Risk factors for the development of postoperative AKI were also studied.ResultsThe incidence of postoperative KDIGO-3 was high (44.2%). Hospital mortality was higher in the AKI group (30.4%) than in the non-AKI group (8.0%). Among the hospital survivors, renal function deterioration to permanent dialysis at two years was also more common in AKI group (14.5%) than in non-AKI group (4.6%). Univariate logistic regression for postoperative AKI revealed male gender, increased age, height, weight, BSA, and BMI, high preoperative serum creatinine, prolonged CPB duration, and decreased CPB target temperature as risk factors. However, multivariate analysis revealed only high preoperative serum creatinine and decreased CPB target temperature as significant risk factors for postoperative AKI.ConclusionTo prevent postoperative AKI in CKD patients, low CPB target temperature is avoided, especially for those with high preoperative serum creatinine levels.     

Role of body mass index on acute kidney injury patients after cardiac surgery

Objective To explore the association between BMI and the risk of developing cardiac surgery associated acute kidney injury (CS-AKI), mortality of AKI and AKI requiring renal replacement therapy (AKI-RRT) after cardiac surgery. Methods Clinical data of patients undergoing cardiac surgery from January 2011 to December 2015 in Zhongshan Hospital of Fudan University were prospectively collected. Patients were divided into four groups according to BMI classification of Chinese population. Adjustment for selection bias was further assessed using propensity score method (PSM) to evaluate the role of BMI in the development of AKI. Results A total of 8442 patients were enrolled, among which 1092 patients successfully matched through PSM. The AKI incidences were respectively 30.3%, 33.3%, 38.6% and 46.8% in four BMI groups (P＜0.01) before PSM. The AKI incidences were respectively 31.9%, 35.2%, 42.5% and 42.9% in four BMI groups (P=0.016) after PSM. The risk of developing AKI increased by 19.9% as the BMI increased per 5 kg/m2 (95%CI: 1.070-1.344, P=0.002). The hospital mortality of patient (overall, AKI, AKI-RRT) in four groups was not statistically different after PSM (P＞0.05), but overweight group always had the lowest mortality. Conclusions BMI is a risk factor for AKI after cardiac surgery, and the AKI incidence increases with increasing BMI in a certain range.     

Pilot double-blind, randomized controlled trial of short-term atorvastatin for prevention of acute kidney injury after cardiac surgery

Aim: To test whether short‐term perioperative administration of oral atorvastatin could reduce incidence of postoperative acute kidney injury (AKI) in cardiac surgical patients. Methods: We conducted a double‐blind, randomized controlled trial in 100 cardiac surgical patients at increased risk of postoperative AKI. Patients were randomized to atorvastatin (40 mg once daily for 4 days starting preoperatively) or identical placebo capsule. Primary outcome was to detect a smaller absolute rise in postoperative creatinine with statin therapy. Secondary outcomes included AKI defined by the creatinine criteria of RIFLE consensus classification (RIFLE R, I or F), change in urinary neutrophil gelatinase‐associated lipocalin (NGAL) concentration, requirement for renal replacement therapy, length of stay in intensive care, length of stay in hospital and hospital mortality. Results: Study groups were well matched. For each patient maximal increase in creatinine during the 5 days after surgery was assessed; median maximal increase was 28 µmol/L in the atorvastatin group and 29.5 µmol/L in the placebo group (P = 0.62). RIFLE R or greater occurred in 26% of patients with atorvastatin and 32% with placebo (P = 0.65). Postoperatively urine NGAL changes were similar (median NGAL : creatinine ratio at intensive care unit admission: atorvastatin group 1503 ng/mg, placebo group 1101 ng/mg; P = 0.22). Treatment was well tolerated and adverse events were similar between groups. Conclusion: Short‐term perioperative atorvastatin use was not associated with a reduced incidence of postoperative AKI or smaller increases in urinary NGAL. (ClinicalTrials.gov NCT00910221).     

非体外循环下冠状动脉旁路移植术后急性肾损伤危险因素分析

目的 分析出非体外循环下行冠状动脉旁路移植术后早期发生急性肾损伤的单因素和多因素危险因子.方法 分析2011年1月-2013年12月在非体外循环下行冠状动脉旁路移植术261例患者的临床资料,根据临床诊断AKI的标准,术后发生急性肾损伤的患者29例(AKI组),男22例,女7例,平均年龄(68.74±10.27)岁;未发生急性肾损伤的患者232例(非AKI组),男179例,女53例,平均年龄(66.26±9.82)岁.总结术前血压、左心室射血分数(LVEF)、左心室内径、血肌酐及术后并发症等,利用SPSS统计软件对急性肾损伤有关的因素进行Logistic回归分析.结果 全组AKI发病率为11.11％(29/261),住院死亡1例.统计学分析结果显示,术前血肌酐含量、麻醉时间、围术期输血是导致冠状动脉旁路移植术后发生AKI的危险因素.结论 AKI是冠状动脉旁路移植术后常见的并发症,术前应认真评估危险因素,加强肾功能保护才能降低AKI发生的风险.     

尿液生物学标记物对肝移植患者术后急性肾损伤早期诊断的价值

目的 探讨尿液中乳酸脱氢酶(lactate dehydrogenase,LDH)、胱抑素C(cystatin C,Cys-C)、中性粒细胞明胶酶相关脂质运载蛋白(neutrophil gelatinase-associated lipocalin,NGAL)对于肝移植患者术后急性肾损伤(acute kindey injury,AKI)早期诊断价值.方法 收集2011年1月～2011年10月在南方医院接受同种异体肝移植术的45例终末期肝病患者术前及手术结束时的静脉血液及尿液标本,检测血清肌酐( serum creatinine,SCr)、胱抑素、LDH及总胆红素,检测尿液中LDH、胱抑素、NGAL.根据AKI网络标准中的SCr标准将患者分为AKI组和非AKI组.比较两组术前、术后尿液中LDH、Cys-C、NGAL的变化情况,并运用受试者工作曲线(receiver operating characteristic curve,ROC)评价LDH、Cys-C、NGAL的准确性.结果 45例患者中20例发生了术后AKI,两组患者的年龄、性别、术前的基本情况、术中手术情况比较差异无统计学意义.AKI组和非AKI组术后血清SCr的差异具有统计学意义[(140±54)比(81±20),P＜0.05].术后AKI组及非AKI组尿液中的LDH、Cys-C、NGAL均升高,AKI组增加明显高于非AKI组.AKI组尿液中LDH、Cys-C、NGAL高于非AKI组,且差异具有统计学意义[(6.50±2.86)比(3.21±1.63),P＜0.05]、[(1.55±0.54)比(0.86±0.31),P＜0.05]、[(107±59)比(43±11),P＜0.05].ROC下面积结果显示,尿液中的LDH、Cys-C、NGAL均显示出了较好的诊断意义,面积分别为0.853、0.833、0.880,大于0.8. 结论 LDH、Cys-C、NGAL均表现出了较好的敏感性和特异性.     

Changes in renal markers and acute kidney injury after marathon running

Background: The impact of marathon running on kidney function has not been previously described. Methods: From 425 marathon runners, 13 women and 12 men were randomly selected and cardiovascular magnetic resonance imaging (MRI) and blood/urine biomarkers were performed 4 weeks before (baseline), immediately after (peak), and 24 h after the race (recovery). Results: Participants were 38.7 ± 9.0 years old and completed the marathon in 256.2 ± 43.5 min. A total of 10/25 (40.0%) met the Acute Kidney Injury Network definition of acute kidney injury (AKI) based on a rise in serum creatinine. There were parallel and similar mean rises in serum creatinine and cystatin C from baseline, to peak, and return to normal in recovery. Urine neutrophil gelatinase‐associated lipocalin rose from 8.2 ± 4.0 to 47.0 ± 28.6 and returned to 10.6 ± 7.2 ng/mL, P < 0.0001. Likewise, the mean urinary kidney injury molecule‐1 levels were 2.6 ± 1.6, 3.5 ± 1.6 and 2.7 ± 1.6 ng/mL (P = 0.001). The mean and minimum pre‐ and post‐IVC (inferior vena cava) diameters by MRI were 24.9, 18.8 and 25.3, 17.5 mm, respectively, suggesting that runners were not volume depleted at the first post‐race measurement. Conclusion: Approximately 40% of marathon runners experience a transient rise in serum creatinine that meets criteria of AKI with a parallel elevation of cystatin C, and supportive elevations of neutrophil gelatinase‐associated lipocalin and kidney injury molecule‐1 in the urine. All biomarker elevations resolved by 24 h. These data suggest that AKI with a transient and minor change in renal filtration function occurs with the stress of marathon running. The impact of repetitive episodes of AKI with long‐distance running is unknown.     

术前预后营养指数对584例心脏手术后患者急性肾损伤的预测价值

目的 评估术前预后营养指数(prognostic nutritional index,PNI)对择期体外循环(cardiopulmonary bypass,CPB)下非冠状动脉旁路移植(coronary artery bypass grafting,CABG)心脏手术后急性肾损伤(acute kidney injury...     

急性肾损伤生物学标志物在心脏外科术后的研究进展

急性肾损伤是心脏外科手术后常见的严重并发症,发病率和病死率均较高.血肌酐及尿量作为急性肾损伤的标志物缺乏敏感性,延误了早期有效的治疗.近年来对于诊断急性肾损伤的生物学标志物方面的研究取得了较大进展,有些指标已逐步进入临床研究阶段,其中包括中性粒细胞明胶酶相关脂质运载蛋白、胱抑素C、肾损伤分子-1、白细胞介素-18等.本文旨在对心脏外科术后急性肾损伤早期生物学标志物基础及临床方面的研究进展作一综述.