Early blood lactate area as a prognostic marker in pediatric septic shock

Abstract

We attempted to evaluate whether the early lactate area is useful as an early prognostic marker of mortality in pediatric septic shock patients. We performed a retrospective study of pediatric patients with septic shock who were admitted to the pediatric intensive care unit of Asan Medical Center, Seoul, Korea. Serial arterial lactate levels were obtained immediately and then every 6 h after admission for a total of 24 h. The lactate area (mmol/lh) was defined as the sum of the area under the curve (AUC) of serial lactate levels measured during the 24 h following admission. We compared the lactate-associated parameters as a predictor of mortality. A total of 65 patients were included in this study, and the overall 28-day mortality of these patients was 26.2%. Survivors compared with non-survivors had an initial lactate level of 3.13 ± 2.79 vs. 6.16 ± 4.87 mmol/l, a lactate clearance of 32.8 ± 63.4 vs. -30.8 ± 75.6%, and a lactate area of 59.7 ± 56.0 vs. 168.0 ± 107.0 mmol/lh (p < 0.05 for all variables). Receiver operating characteristic curves indicated a strong predictive power for the lactate area (AUC = 0.828), which demonstrated the largest AUC in comparison with the AUCs of the initial lactate level (0.699) or the 24-h lactate clearance (0.719). Using multivariate logistic regression analysis, the lactate area was a significant prognostic factor. The early lactate area is a potentially feasible and clinically useful predictor of mortality in pediatric septic shock patients.