Abstract 239: Initial Cytokine Levels Are Associated With Outcome After Cardiac Arrest

Abstract

Background: The post arrest syndrome is characterized, in part, by a systemic inflammatory state whose molecular mechanisms and association with survival remain poorly understood. A deeper understanding of cytokine activity post arrest may identify an early biomarker for outcomes as well as a potential therapeutic target. Hypothesis: Cytokine elevation is associated with survival after cardiac arrest (CA) and ROSC. Methods: One hundred eleven consecutive patients (pts) enrolled in the multicenter Characterization of Mitochondrial Injury after Cardiac Arrest (COMICA) study underwent serial serum measurements for IL-6, IL-8, IL-10, and TNFα via a Millipore Multiplex Human Cytokine Panel at Time 0 (T0) defined as upon arrival to the hospital, and 12, 24, 36, and 48 hours post ROSC. We assessed the ability (sensitivity, specificity, and area under the receiver operating curve (ROC)) of these cytokines drawn at T0 to predict survival to hospital discharge. A repeated measures ANOVA was fit with a between subjects factor (Group: Survived, Expired), a within subjects factor (Time: 0, 12, 24, 38, 48) and the interaction between these two factors. Values are presented as mean ± SEM. Results: The areas under the ROC [sensitivity, specificity] were: IL-6= .894 [.732, .837]; IL-8= .800 [.851, .696]; IL-10= .738 [.738, .745]; and TNFα= .512 [.975, .143]. The repeated measures ANOVA analysis for IL-6, which had the best predictive value, is shown in the Figure. There was a significant Group x Time interaction (p=0.0022) and post-hoc tests revealed a significant difference in Log(IL6) at T0 (p 6.72 at baseline is approximately 19 times (OR=18.68, 95% CI (6.60, 52.90)) more likely to die before being discharged than a pt with Log(IL6) < 6.72. Conclusion: Early IL-6 levels are strongly associated with outcome after CA. Further investigation is needed to determine molecular mechanisms and potential for use as an early marker of outcome in post arrests pts.