The clinical significance of blood lactate levels in evaluation of adult patients with Veno-Arterial Extracorporeal Membrane Oxygenation

Funding Acknowledgements Type of funding sources: None. Background Veno-Arterial ECMO is a life supporting procedure that can be done to the patients with cardiogenic shock which is associated with hyperlactatemia . The objective of this study was to detect the validity of serial measurements of arterial lactate level in differentiating hospital mortality and neurological outcome after VA-ECMO support. Results : This retrospective study included 106 patients between 2015 and 2019 with a mean age of 40.2 ± 14.4 years and mostly males (69.8%) . The in-hospital mortality occurred in 56.6% and acute strokes occurred in 25.5% of the patients . The non-survivors and the patients with acute strokes had significantly higher arterial lactate levels at pre-ECMO initiation , post-ECMO peak and after 24 hours of ECMO support compared to the survivors and those without strokes respectively. The peak arterial lactate ≥ 14.65 mmol/L measured after ECMO support had 81.7 % sensitivity and 89.1 % specificity for predicting hospital mortality [AUROC: 0.889 , p <0.001 ] while the arterial lactate level ≥ 3.25 mmol/L after 24 hours of ECMO support had 88.3% sensitivity and 97.8% specificity for predicting hospital mortality [AUROC: 0.93 , p <0.001 ]. The peak lactate ≥ 15.15 mmol/L measured after ECMO support had 70.8 % sensitivity and 69 % specificity for predicting cerebral strokes [AUROC: 0.717 , p <0.001 ] while the lactate level ≥ 3.25 mmol/L after 24 hours of ECMO support had 79.2% sensitivity and 72.4% specificity for predicting cerebral strokes [AUROC: 0.779, p <0.001 ]. Progressive hyperlactatemia (OR = 1.427 , 95% CI : 1.048 – 1.944 , p = 0.024 ) and increasing SOFA score after 48 hours (OR = 1.819 , 95% CI : 1.374 – 2.409 , p < 0.001) were significantly associated with in-hospital mortality after VA-ECMO support. Conclusion : Progressive hyperlactatemia after VA-ECMO initiation for adult patients with cardiogenic shock is a sensitive and specific predictor of hospital mortality and acute cerebrovascular strokes . According to our results , we could recommend early VA-ECMO initiation to achieve adequate circulatory support and better outcome. Predictors of hospital mortality.Studied variablesP valueOR95% CI for ORLactate peak0.0241.4271.048 - 1.944Hemodialysis0.3154.1260.344 - 51.669Atrial fibrillation0.073.2680.786 - 31.26Cardiac surgeries0.2173.4820.480 - 25.152Δ SOFA<0.0011.8191.374 - 2.409Central VA-ECMO0.123.9310.482 - 24.16Abstract Figure. ROC of lactate differentiating mortality