Neutrophil Gelatinase-Associated Lipocalin as a Diagnostic Marker for Acute Kidney Injury in Oliguric Critically Ill Patients: A Post-Hoc Analysis.

BACKGROUND: Oliguria occurs frequently in critically ill patients, challenging clinicians to distinguish functional adaptation from serum-creatinine-defined acute kidney injury (AKIsCr). We investigated neutrophil gelatinase-associated lipocalin (NGAL)'s ability to differentiate between these 2 conditions. METHODS: This is a post-hoc analysis of a prospective cohort of adult critically ill patients. Patients without oliguria within the first 6 h of admission were excluded. Plasma and urinary NGAL were measured at 4 h after admission. AKIsCr was defined using the AKI network criteria with pre-admission serum creatinine or lowest serum creatinine value during the admission as the baseline value. Hazard ratios for AKIsCr occurrence within 72 h were calculated using Cox regression and adjusted for risk factors such as sepsis, pre-admission serum creatinine, and urinary output. Positive predictive values (PPV) and negative predictive values (NPV) were calculated for the optimal cutoffs for NGAL. RESULTS: Oliguria occurred in 176 patients, and 61 (35%) patients developed AKIsCr. NGAL was a predictor for AKIsCr in univariate and multivariate analysis. When NGAL was added to a multivariate model including sepsis, pre-admission serum creatinine and lowest hourly urine output, it outperformed the latter model (plasma p = 0.001; urinary p = 0.048). Cutoff values for AKIsCr were 280 ng/ml for plasma (PPV 80%; NPV 79%), and 250 ng/ml for urinary NGAL (PPV 58%; NPV 78%). CONCLUSIONS: NGAL can be used to distinguish oliguria due to the functional adaptation from AKIsCr, directing resources to patients more likely to develop AKIsCr.

Targeting oliguria reversal in perioperative restrictive fluid management does not influence the occurrence of renal dysfunction: A systematic review and meta-analysis.

BACKGROUND: Interest in perioperative fluid restriction has increased, but it could lead to hypovolaemia. Urine output is viewed as a surrogate for renal perfusion and is frequently used to guide perioperative fluid therapy. However, the rationale behind targeting oliguria reversal - achieving and maintaining urine output above a previously defined threshold by additional fluid boluses - is often questioned. OBJECTIVE: We assessed whether restrictive fluid management had an effect on oliguria, acute renal failure (ARF) and fluid intake. We also investigated whether targeting oliguria reversal affected these parameters. DESIGN: Systematic review of randomised controlled trials with meta-analyses. We used the definitions of restrictive and conventional fluid management as provided by the individual studies. DATA SOURCES: We searched MEDLINE (1966 to present), EMBASE (1980 to present), and relevant reviews and articles. ELIGIBILITY CRITERIA: We included randomised controlled trials with adult patients undergoing surgery comparing restrictive fluid management with a conventional fluid management protocol and also reporting the occurrence of postoperative ARF. RESULTS: We included 15 studies with a total of 1594 patients. There was insufficient evidence to associate restrictive fluid management with an increase in oliguria [restrictive 83/186 vs. conventional 68/230; odds ratio (OR) 2.07; 95% confidence interval (CI), 0.97 to 4.44; P = 0.06; I = 23.7%; Nstudies = 5]. The frequency of ARF in restrictive and conventional fluid management was 20/795 and 20/799, respectively (OR 1.07; 95% CI, 0.60 to 1.92; P = 0.8; I = 17.5%; Nstudies = 15). There was no statistically significant difference in ARF occurrence between studies targeting oliguria reversal and not targeting oliguria reversal (OR 0.31; 95% CI, 0.08 to 1.22; P = 0.088). Intraoperative fluid intake was 1.89 l lower in restrictive than in conventional fluid management when not targeting oliguria reversal (95% CI, -2.59 to -1.20 l; P < 0.001; I = 96.6%; Nstudies = 7), and 1.63 l lower when targeting oliguria reversal (95% CI, -2.52 to -0.74 l; P < 0.001; I = 96.6%; Nstudies = 6). CONCLUSION: Our data suggest that, even though event numbers are small, perioperative restrictive fluid management does not increase oliguria or postoperative ARF while decreasing intraoperative fluid intake, irrespective of targeting reversal of oliguria or not.

Intraoperative glycemic control without insulin infusion during pediatric cardiac surgery for congenital heart disease.

BACKGROUND: Many studies are reporting that the occurrence of hyperglycemia in the postoperative period is associated with increased morbidity and mortality rates in children after cardiac surgery for congenital heart disease. This study sought to determine blood glucose levels in standard pediatric cardiac anesthesiological management without insulin infusions. METHODS: The study population consisted of 204 consecutive pediatric patients aged from 3 days to 15.4 years undergoing open cardiac surgery for congenital heart disease between June 2007 and January 2009. Glucose-containing fluids were not administrated intraoperatively, and all patients received high dose of opioids (sufentanil 10 mcg·kg(-1) ) and steroids (30 mg·kg(-1) methylprednisolone) iv. Glucose levels were measured before CPB, 10 min after initiation of CPB, every hour on CPB, post-CPB, and on arrival at intensive care unit (ICU). RESULTS: Intraoperatively, only one patient had a glucose level <50 mg·dl(-1) (=34.2 mg·dl(-1) ), 57/204 patients (27.9%) had at least one intraoperative glucose >180 mg·dl(-1) , but only 12 patients (5.8%) had a glucose level >180 mg·dl(-1) at ICU arrival. Thirty-day mortality was 1.5% (3/204). Younger age, lower body weight, and lower CPB temperature were associated with hyperglycemia at ICU arrival, as were higher RACHS and Aristotle severity scores. CONCLUSION: A conventional (no insulin, no glucose) anesthetic management seems sufficient in the vast majority of patients (96.5%). Special attention should be paid to small neonates with complex congenital heart surgery, in whom insulin treatment may be contemplated.