Lactate clearance prognosticates outcome in pediatric septic shock during first 24 h of intensive care unit admission

Abstract

This study was undertaken to examine the clinical utility of lactate clearance as an indicator of mortality in pediatric septic shock, and to compare the performance of lactate clearance at 6, 12, and 24 h for predicting in-hospital and 60-day mortality. Pediatric patients with septic shock were prospectively studied. Vital signs, laboratory values, Pediatric Risk of Mortality Score, and pediatric logistic organ dysfunction score were obtained at presentation (hour 0), hour 6, hour 24 and over the first 72 h of hospitalization. Lactate clearance was obtained at 6, 12, and 24 h of hospital admission. Therapy received, outcome parameters of mortality, and duration of hospitalization were recorded. The primary outcome variable of 60-day mortality rate was 31.25%. Only lactate clearance at 6 and 24 h was significantly associated with mortality, with odds of 0.97 (95% CI, 0.951–981; p < 0.001) and 0.975 (95% CI, 0.964–0.986; p < 0.001), respectively. Approximately there was a 24% decrease in likelihood of mortality for each 10% increase in lactate clearance at 24 h. At a threshold value of 10% 6-h lactate clearance had a sensitivity of 0.948 and specificity of 0.571, while at a threshold of 20% 24-h lactate clearance had a sensitivity of 0.922 and specificity of 0.629. The comparison of clearance at 6 and 24 h using receiver operating characteristic showed that former was “fair” (area under the curve = 0.753) and later was “good” (area under the curve = 0.81) in predicting mortality in pediatric septic shock. Conclusion: We concluded that optimal lactate clearance in pediatric septic shock both during the early presentation and after the initial “golden hours” is associated with lower in-hospital and 60-day mortality. Further, 24-h lactate clearance appears superior to 6 h lactate clearance in predicting mortality in such patients.