Very Transient Cases of Acute Kidney Injury in the Early Postoperative Period After Cardiac Surgery: The Relevance of More Frequent Serum Creatinine Assessment and Concomitant Urinary Biochemistry Evaluation.

To evaluate if more frequent serum creatinine (sCr) measurements in the early postoperative period (first 48 hours) after cardiac surgery would help in early diagnosis of acute kidney injury (AKI), as well as reveal cases of AKI duration of fewer than 24 hours (vtAKI). The sequential blood and urinary biochemical profile of patients who developed vtAKI was compared with that of the patients who did not develop AKI or who developed AKI for more than 48 hours (pAKI). A retrospective analysis of prospectively collected data. Two intensive care units of 2 private hospitals. Twenty-nine patients who underwent cardiac surgery who had 6 values of serum creatinine (sCr) measured within the first 48 hours after surgery and concomitant spot urine samples for urine biochemistry assessment. None. Eighteen patients (62%) developed Acute Kidney Injury Network (AKIN) sCr-based AKI, half of them for fewer than 24 hours. Most AKI patients had the sCr increase diagnosed 6 to 12 hours after surgery. When comparing the sequential alterations of blood and urinary parameters among patients with no AKI, vtAKI, and pAKI, the authors found that most of them were similar among groups, differing only in magnitude and duration. More frequent sCr measurements in the early postoperative period, together with urine biochemistry assessment, have the potential to anticipate AKI diagnosis after cardiac surgery and reveal cases of very transient AKI usually not diagnosed in current practice. The clinical relevance of these findings must be evaluated in larger, prospective studies.

Maciel AT ，Nassar AP Jr ，Vitorio D 《-》

Urinary, Plasma, and Serum Biomarkers' Utility for Predicting Acute Kidney Injury Associated With Cardiac Surgery in Adults: A Meta-analysis.

Early accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve morbidity and mortality. Although several novel biomarkers have been developed for the early detection of AKI, their clinical utility in the critical intraoperative and immediate postoperative period remains unclear. Systematic review and meta-analysis. Adult patients having cardiac surgery. EMBASE, CINAHL, Cochrane Library, Scopus, and PubMed from January 1990 until January 2015 were systematically searched for cohort studies reporting the utility of novel biomarkers for the early diagnosis of AKI after adult cardiac surgery. Reviewers extracted data for study design, population, timing of biomarker measurement and AKI occurrence, biomarker performance (area under the receiver operating characteristic curve [AUROC]), and risk of bias. Novel urine, plasma, and serum AKI biomarkers, measured intraoperatively and in the early postoperative period (<24 hours). AKI was defined according to the RIFLE, AKIN, or 2012 KDIGO criteria. We found 28 studies reporting intraoperative and/or early postoperative measurement of urine (n=23 studies) or plasma or serum (n=12 studies) biomarkers. Only 4 of these studies measured biomarkers intraoperatively. Overall, intraoperative discrimination by the urine biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury marker 1 (KIM-1) demonstrated AUROCs<0.70, whereas N-acetyl-β-d-glucosaminidase (NAG) and cystatin C had AUROCs<0.75. In the immediate 24-hour postoperative period, the urine biomarkers NGAL (16 studies), KIM-1 (6 studies), and liver-type fatty acid binding protein (6 studies) exhibited composite AUROCs of 0.69 to 0.72. The composite AUROCs for postoperative urine cystatin C, NAG, and interleukin 18 were ≤0.70. Similarly, the composite AUROCs for postoperative plasma NGAL (6 studies) and cystatin-C (5 studies) were <0.70. Heterogeneous AKI definitions. In adults, known urinary, plasma, and serum biomarkers of AKI possess modest discrimination at best when measured within 24 hours of cardiac surgery.

Ho J ，Tangri N ，Komenda P ，Kaushal A ，Sood M ，Brar R ，Gill K ，Walker S ，MacDonald K ，Hiebert BM ，Arora RC ，Rigatto C ... -  《-》

Association of definition of acute kidney injury by cystatin C rise with biomarkers and clinical outcomes in children undergoing cardiac surgery.

Zappitelli M ，Greenberg JH ，Coca SG ，Krawczeski CD ，Li S ，Thiessen-Philbrook HR ，Bennett MR ，Devarajan P ，Parikh CR ，Translational Research Investigating Biomarker Endpoints in Acute Kidney Injury (TRIBE-AKI) Consortium ... -  《-》

Combination of two urinary biomarkers predicts acute kidney injury after adult cardiac surgery.

Urinary L-type fatty acid-binding protein (L-FABP) has not been evaluated for adult post-cardiac surgery acute kidney injury (AKI) to date. This study was undertaken to evaluate a biomarker panel consisting of urinary L-FABP and N-acetyl-β-D-glucosaminidase (NAG), a more established urinary marker of kidney injury, for AKI diagnosis in adult post-cardiac surgery patients. This study prospectively evaluated 77 adult patients who underwent cardiac surgery at 2 general hospitals. Urinary L-FABP and NAG were measured before surgery, at intensive care unit arrival after surgery (0 hours), 4, and 12 hours after arrival. The AKI was diagnosed by the Acute Kidney Injury Network criteria. Of 77 patients, 28 patients (36.4%) developed AKI after surgery. Urinary L-FABP and NAG were significantly increased. However, receiver operating characteristic (ROC) analysis revealed that the biomarkers' performance was statistically significant but limited for clinical translation (area under the curve of ROC [AUC-ROC] for L-FABP at 4 hours 0.72 and NAG 0.75). Urinary L-FABP showed high sensitivity and NAG detected AKI with high specificity. Therefore, we combined these 2 biomarkers, which revealed that this combination panel can detect AKI with higher accuracy than either biomarker measurement alone (AUC-ROC 0.81). Moreover, this biomarker panel improved AKI risk prediction significantly compared with predictions made using the clinical model alone. When urinary L-FABP and NAG are combined, they can detect AKI adequately, even in a heterogeneous population of adult post-cardiac surgery AKI. Combining 2 markers with different sensitivity and specificity presents a reasonable strategy to improve the diagnostic performance of biomarkers.

Katagiri D ，Doi K ，Honda K ，Negishi K ，Fujita T ，Hisagi M ，Ono M ，Matsubara T ，Yahagi N ，Iwagami M ，Ohtake T ，Kobayashi S ，Sugaya T ，Noiri E ... -  《-》

Early Postoperative Serum Creatinine Adjusted for Fluid Balance Precisely Predicts Subsequent Acute Kidney Injury After Cardiac Surgery.

Cumulative fluid overload may influence acute kidney injury (AKI) diagnosis due to the dilution effect. The authors hypothesized a small increase of early postoperative serum creatinine (SCr) adjusted for fluid balance might have superior discrimination ability in subsequent AKI prediction. Retrospective analyses. A single-center study in a university hospital. The study comprised 1,016 adult patients who underwent elective isolated or combined valve surgery in 2015. None. Baseline characteristics, intraoperative parameters, and intraoperative and postoperative fluid balance were collected through a retrospective chart review. Early postoperative SCr level was drawn within 12 hours of surgical completion and then measured daily. Early relative changes of SCr were categorized as a cutoff value of 10% with or without adjustment for cumulative fluid balance. Kidney Disease: Improving Global Outcomes criteria were used to detect AKI. Logistic analyses were performed to determine risk factors for subsequent AKI with the inclusion of measured or fluid-adjusted early relative changes of SCr, respectively. In this study, 355 patients (34.9%) developed AKI. Multivariate logistic analyses showed age, weight, European System for Cardiac Operative Risk Evaluation II, and cardiopulmonary bypass duration were associated independently with the development of AKI. Model discrimination for AKI prediction was improved significantly when the addition of measured (area under the receiver operating characteristic curve [AUROC] 0.830) and fluid-adjusted early changes of SCr to the basic model (AUROC 0.850). Early fluid-adjusted relative changes of SCr could improve the predictive ability for subsequent development of AKI in valve surgery patients.

Jin J ，Chang SC ，Xu S ，Xu J ，Jiang W ，Shen B ，Hu J ，Zhuang Y ，Wang C ，Teng J ，Ding X ... -  《-》