Abstract 110: Brain Injury Biomarkers Are Associated With Poor Neurological Outcomes Within 24 Hours After Refractory VT/VF Cardiac Arrest Requiring Extracorporeal Cardiopulmonary Resuscitation

Background: Extracorporeal cardiopulmonary resuscitation (ECPR) is an emerging method that improve survival after refractory VF/VT cardiac arrest. Neuron-specific enolase (NSE) and S-100B are used to predict neurological outcome; however, it is unclear the reliability and earliest time point during ECPR.

Methods: Single-center, retrospective cohort study included OHCA patients who underwent ECPR at the University of Minnesota between December 2015 and January 2023. NSE and S100B levels were obtained at admission, at 12 and 24h after ROSC in a total of 361 unconscious patients. The primary outcome was poor neurological outcome (defined as CPC 3-5) at hospital discharge. We evaluated the optimal cut-off levels for NSE and S100B by maximizing the Youden index and ROC analyses for poor clinical results. Finally, NSE and S100B at 12h and 24h were added to a multivariable logistic model (age, sex, bystander and witnessed).

Results: Of 361 patients, 170 survived to hospital admission. Of these 85% (145/170) survived neurologically favorable. Mean (SD) NSE (ng/mL) values were significantly higher in the CPC 3-5 group at every time point, 52.3 (53) vs 21.1 (12) on admission; 92.8 (92) vs 20 (10) after 12h; 107.1(94.4) vs 21.5 (12.9) after 24h; p<0.01 at all time points. Again, mean (SD) S100B (ng/L) values were significantly higher in the CPC 3-5 group at every time point 3912 (990) vs 986 (920) on admission; 3975 (4972) vs 272.2 (209) after 12h; 4454 (7300) vs 192 (239) after 24h; p<0.01 at all time points. At 24h, NSE and S100B significantly predicted poor neurological outcome with AUC 0.92; 95%CI:0.87-0.95 (optimal NSE cut-off value of 47) and 0.91; 95%CI: 0.87-0.95 (optimal cut-off S100B value of 354), respectively. High concentrations of both biomarkers at 24h (NSE: odds ratio [OR] 2.4 per 1 ng/mL, p<0.001; S100B: odds ratio [OR] 1.1 per 1 ng/L, p<0.05) were independent for poor outcome in a multivariate analysis. Additionally, the combination of both markers (AUC, 0.94; 95%CI: 0.91-0.97) showed significantly higher predictive performance than when using them individually.

Conclusions: By using serial measurements, high NSE and S100B levels may help early predict progression to poor neurological outcome in OHCA survivors requiring ECPR in the first 24h after ROSC.