Rate of increase in serum lactate level risk-stratifies infants after surgery for congenital heart disease.

Increased blood lactate levels reflect tissue oxygen debt and might be indicative of low cardiac output. We hypothesized that the rate of increase in serum lactate would be an ideal marker to discriminate between infants at high and low risk of a poor outcome after surgical repair of congenital heart disease using cardiopulmonary bypass. In the present prospective, observational study in a pediatric cardiac intensive care unit, infants (aged <12 months) undergoing cardiac surgery had serial whole blood lactate levels measured with every arterial blood gas drawn for the first 24 postoperative hours. The composite poor outcome included death, the need for extracorporeal support, and dialysis. The lactate levels were measured in 231 infants; 19 infants (8.2%) had a poor outcome. A lactate increase rate of 0.6 mmol/L/h had very good discriminatory ability (area under the curve [AUC], 0.89) with a sensitivity of 90%, specificity of 84%, positive predictive value (PPV) of 34%, and negative predictive value (NPV) of 99%. Similar results were obtained for subgroups stratified by 1- or 2-ventricle heart disease and risk adjustment for congenital heart surgery (RACHS-1) score. In neonates (age <30 days) with single-ventricle physiology (n = 43, poor outcome = 8), a lactate increase of 0.6 mmol/L/h had near perfect discriminatory ability (AUC 0.99) with a sensitivity of 100%, specificity of 51%, PPV of 32%, and NPV of 100%. In 2-ventricle neonates (n = 43, poor outcome = 5), a lactate increase of 0.6 mmol/L/h also had near perfect discriminatory ability (AUC, 0.99), with a sensitivity of 100%, specificity of 90%, PPV of 56%, and NPV of 100%. The postoperative lactate increase rate allows discrimination between infants at high and low risk of morbidity and mortality after congenital heart disease surgery, and the lactate level can be followed serially for the treatment response.

Schumacher KR ，Reichel RA ，Vlasic JR ，Yu S ，Donohue J ，Gajarski RJ ，Charpie JR ... -  《-》

Cerebral tissue oxygenation index and lactate at 24 hours postoperative predict survival and neurodevelopmental outcome after neonatal cardiac surgery.

There are no well-established noninvasive biomarkers for identifying patients at risk for poor outcome after surgery for congenital heart disease. Few studies have assessed prognostic accuracy of cerebral tissue oxygenation index (cTOI) measured by near infrared spectroscopy (NIRS). To assess the utility of noninvasive NIRS monitoring as a predictor of outcomes after neonatal cardiac surgery through measurement of cTOI. To examine the utility of noninvasive NIRS monitoring in combination with lactate concentration and inotropic score in prediction of outcomes after neonatal cardiac surgery. Prospective longitudinal cohort study. Operating room and cardiac intensive care unit, Children's National Heart Institute. Seventy-five patients with complex congenital heart disease undergoing surgical repair within first month of life. Cerebral TOI, blood lactate, and inotropic scores were measured preoperative, intraoperative and up to 24 hours postoperative. Postoperative mortality and neurodevelopmental outcome assessed by the Bayley Scales of Infant Development (BSID II). Mental and motor scores were obtained at 6, 15, and 21 months. Good outcome was defined as survival and BSID mental and motor scores ≥70 points. Poor outcome was defined as death or BSID scores <70 at most recent follow-up. Cohort of 75 patients prospectively followed including 40 patients with single ventricle and 35 with two ventricles. Four patients died before discharge and ten died within 21 months. Seven patients were lost to follow-up. Among survivors with follow-up (n = 54), BSID was abnormal in 25 (46%). Patients with poor outcome (n = 39) had lower mean cTOI 60 minutes off-CPB (48% vs. 58%, P = .003) and 24 hours postoperative (49% vs. 59%, P < .001), higher lactate (8.2 vs. 5.0 mmol/L, P = .005) and higher inotropic scores (10 vs. 6, P = .02) at 24 hours postoperative. ROC analysis indicated that cTOI had moderate predictive accuracy of outcome (AUC = 0.751, P < .001). Multivariable regression analysis confirmed that predictive accuracy was improved using both cTOI and lactate at 24 hours postoperative (AUC = 0.813, 95% CI: 0.705-0.921, P < .001) with optimal cutoff values <58% and >7.4 mmol/L, respectively (sensitivity = 95%). Cerebral TOI combined with lactate at 24 hours postoperative are accurate non-invasive predictive biomarkers of patient survival and neurodevelopmental outcome in neonates with CHD undergoing cardiac surgery.

Aly SA ，Zurakowski D ，Glass P ，Skurow-Todd K ，Jonas RA ，Donofrio MT ... -  《-》

Serial blood lactate measurements predict early outcome after neonatal repair or palliation for complex congenital heart disease.

Charpie JR ，Dekeon MK ，Goldberg CS ，Mosca RS ，Bove EL ，Kulik TJ ... -  《JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY》

Postoperative lactate concentrations predict the outcome of infants aged 6 weeks or less after intracardiac surgery: a cohort follow-up to 18 months.

Cheung PY ，Chui N ，Joffe AR ，Rebeyka IM ，Robertson CM ，Western Canadian Complex Pediatric Therapies Project, Follow-up Group ... -  《JOURNAL OF THORACIC AND CARDIOVASCULAR SURGERY》

Mortality prediction after cardiac surgery: blood lactate is indispensible.

Blood lactate is accepted as a mortality risk marker in intensive care units (ICUs), especially after cardiac surgery. Unfortunately, most of the commonly used ICU risk stratification scoring systems did not include blood lactate as a variable. We hypothesized that blood lactate alone can predict the risk of mortality after cardiac surgery with an accuracy that is comparable to those of other complex models. We therefore evaluated its accuracy at mortality prediction and compared it with that of other widely used complex scoring models statistically. We prospectively collected data of all consecutive adult patients who underwent cardiac surgery between January 1, 2007, and December 31, 2009. By using χ2 statistics, a blood lactate-based scale (LacScale) with only four cutoff points was constructed in a developmental set of patients (January 1, 2007, and May 31, 2008). LacScale included five categories: 0 (≤ 1.7 mmol/L); 1 (1.8-5.9 mmol/L), 2 (6.0-9.3 mmol/L), 3 (9.4-13.3 mmol/L), and 4 (≥ 13.4 mmol/L). Its accuracy at predicting ICU mortality was evaluated in another independent subset of patients (validation set, June 1, 2008, and December 31, 2009) on both study-population level (calibration analysis, overall correct classification) and individual-patient-risk level (discrimination analysis, ROC statistics). The results were then compared with those obtained from other widely used postoperative models in cardiac surgical ICUs (Sequential Organ Failure Assessment [SOFA] score, Simplified Acute Physiology Score II [SAPS II], and Acute Physiology and Chronic Health Evaluation II [APACHE II] score). ICU mortality was 5.8% in 4,054 patients. LacScale had a reliable calibration in the validation set (2,087 patients). It was highly accurate in predicting ICU mortality with an area under the ROC curve (area under curve [AUC]; discrimination) of 0.88. This AUC was significantly larger than that of all the other models (SOFA 0.83, SAPS II: 0.79 and APACHE II: 0.76) according to DeLong's comparison. Integrating the LacScale in those scores further improved their accuracy by increasing their AUCs (0.88, 0.81, and 0.80, respectively). This improvement was also highly significant. Blood lactate accurately predicts mortality at both individual patient risk and patient cohort levels. Its precision is higher than that of other commonly used "complex" scoring models. The proposed LacScale is a simple and highly reliable model. It can be used (at bedside without electronic calculation) as such or integrated in other models to increase their accuracy.

Badreldin AM ，Doerr F ，Elsobky S ，Brehm BR ，Abul-dahab M ，Lehmann T ，Bayer O ，Wahlers T ，Hekmat K ... -  《-》