Serum lactate as a predictor of mortality after paediatric cardiac surgery

Abstract

Objective-To assess the value of sequential lactate measurement in predicting postoperative mortality after surgery for complex congenital heart disease in children. Design-Prospective observational study. Setting-Sixteen bedded paediatric intensive care unit (PICU). Subjects-Ninety nine children ( 90 survivors, nine non-survivors). Measurements-Serum lactate and base deficit were measured on admission and every six hours thereafter. Data were analysed by Mann-Whitney and Fisher's exact tests.Results-There was considerable overlap in initial lactate values between the survivor and non-survivor groups. Initial lactate was significantly raised in nonsurvivors (median 8.7, range 1.9-17.6 mmol/l) compared with survivors (median 2.4, range 0.6-13.6 mmol/l) (p = 0.0002). Twenty one patients (21.1%) with initial lactate concentrations greater than 4.5 mmol/l survived to PICU discharge. Using receiver operating characteristic analysis an initial lactate of 6 mmol/l had the optimum predictive value for mortality. Initial postoperative serum lactate >6 mmol/l predicted mortality with sensitivity 78%, specificity 83%, and positive predictive value of only 32%. Conclusion-Initial lactate concentrations have poor positive predictive value for mortality. The routine measurement of lactate for this purpose cannot be justified in clinical practice.

Prognostic Value of Red Cell Distribution Width in Critically Ill Patients and Comparison with Intensive Care Unit Scoring Systems

“…Higher lactate values must be considered as a useful indicator in identifying the severity of diseases and mortality rates (16)(17)(18)(19). On the contrary, some studies showed the first lactate values as a weak indicator of mortality (20). The present study found a statistically significant difference between lactate values at first admission and at 24 h, mean values at 24 h, 48 h, and during the stay, and 28-day and 3-month mortalities.…”

Correlation between serum lactate levels and outcome in pediatric patients undergoing congenital heart surgery

“…However, the design of these studies was different, as the cut-off lactate levels were calculated as 3-6 mmol/L. [8,[12][13][14] Molina Hazan et al [8] found that maximum lactate levels (within postoperative first 12 hours) were correlated with the duration of CPB, duration of aortic cross-clamp, the RACHS-1 subgroups, and inotropic scores. Maarslet et al [12] reported that young age, low weight, high RACHS-1 scores, prolonged duration of CPB, and inotropic use were risk factors for elevated lactate.…”

“…However, they were unable to find a correlation between increased lactate levels and duration of intubation and ICU stay. Hatherill et al [13] showed that lactate levels >6 mmol/L were weak positive predictive values for mortality on admission to the ICU. Another study reported that increased lactate levels were correlated with the stage of hypothermia in CPB, duration of cardioplegic arrest, duration of mechanical ventilation, and the ICU stay.…”

Mortality prediction following CABG surgery: comparison of EuroSCORE vs general risk scoring systems

“…On the other hand, some of physiological variables, like potassium concentration, might be affected by potassium used in cardioplegia for myocardial protection, lower body temperature -impact of anesthethic and perfusion technique used during the CPB, and these changes perhaps do not have any impact on patient mortality and morbidity. On the contrary, increased lactates concentration which has been proven to be an important predictor of bad outcome in pediatric and adult cardiac surgery (13,14) was not included in the general risk scoring systems. In our study, discrimination of the general risk scoring system (APACHE II) used postoperatively was not as accurate as that of EuroSCORE risk stratification, based on preoperative patient characteristics.…”