Peak Blood Lactate at 24 h after ECMO Can Predict 30-day Mortality in Infants after Complex Cardiac Surgery

Objective: Peak blood lactate at 24 h after extracorporeal membrane oxygenation (ECMO) can predict 30-day mortality in infants after complex cardiac surgery. Methods: Twenty-eight infants with ECMO after complex congenital heart disease surgery were selected from March 2019 to March 2022 in our hospital. The infants were divided into survival group (n = 11) and non-survival group (n = 17) according to 30-day survival after discharge from hospital. The risk factors at 30-day mortality after discharge were analyzed by Cox regression analysis. Results: When compared to the non-survival group, there were significant differences in peak blood lactate at 24 h after ECMO, liver dysfunction and multiple organ dysfunction syndrome (MODS) in the survival group (p < 0.05). Cox regression analysis showed that peak blood lactate at 24 h after ECMO (HR = 1.074, 95% CI: 1.005–1.149, p = 0.036) and MODS (HR = 4.120, 95% CI: 1.373–12.362, p = 0.012) were related risk factors affecting the prognosis of infants. The best cutoff value for the peak blood lactate at 24 h after ECMO was 10.2 mmol/L. The area under the curve (AUC) for predicting the 30-day survival rate of the ECMO assisted infants after discharge from hospital was 0.770 (95% CI: 0.592–0.948, p = 0.018), with a sensitivity of 94.1% and specificity of 54.5%. Conclusion: The peak blood lactate at 24 h after ECMO can predict the 30-day mortality after discharge of infants treated with ECMO after complex cardiac surgery. The best cut-off value for peak blood lactate at 24 h after ECMO was 10.2 mmol/L.