Positive association between arterial blood lactate level before extra-corporeal membrane oxygenation and 30-day mortality in pediatric patients with severe cardiopulmonary failure

Introduction This study aimed to investigate the relationship between blood lactate level and mortality in pediatric patients receiving extracorporeal membrane oxygenation (ECMO) for severe cardiopulmonary failure. Methods A retrospective observational study was conducted on pediatric patients who received ECMO from January 2013 to December 2021 at the Seventh Medical Center of PLA General Hospital. Patient demographic characteristics, arterial blood lactate level prior to ECMO (pre-ECMO), ECMO settings, ECMO duration, and 30-days mortality were retrieved from patients’ medical records. The relationships between pre-ECMO blood lactate level and mortality were interpreted using the logistic regression analysis and Kaplan-Meier survival analysis. Results A total of 160 pediatric patients who had either refractory respiratory failure ( n = 89) or circulatory failure ( n = 71) and received ECMO were included in this study. In both the respiratory failure and circulatory failure groups, the non-survivors showed a higher mean pre-ECMO arterial blood lactate level than the survivors. In the respiratory failure group, a pre-ECMO lactate concentration at ≥11.6 mmol/L had a sensitivity of 51% and a specificity of 82% for predicting mortality. In the circulatory failure group, a pre-ECMO lactate concentration at ≥7.2 mmol/L had a sensitivity of 90% and a specificity of 57% for predicting mortality. The Kaplan-Meier survival curves showed that respiratory failure patients with a pre-ECMO lactate level over 11.6 mmol/L or circulatory failure patients with a pre-ECMO lactate level over 7.2 mmol/L had a higher 30-days mortality rate than those with a lower lactate level. Conclusions High pre-ECMO arterial blood lactate level serves as an independent risk factor for mortality in pediatric patients who receive ECMO for severe cardiopulmonary failure.