Background
Extracorporeal life support (ECLS) is increasingly employed for severe respiratory or cardiac failure, alongside a rising adoption of extracorporeal cardiopulmonary resuscitation (eCPR). Despite increased adoption, limited evidence underscores possible cytokines’ pivotal role in the inflammatory response during ECLS.
Methods
The study involved 546 eCPR patients using veno-arterial extracorporeal membrane oxygenation from 2013 to 2023. Categorized into in-hospital eCPR (IHCA, 358 patients) and out-of-hospital eCPR (OHCA, 188 patients) groups, a retrospective analysis explored associations among interleukin 6 (IL6), interleukin 8 (IL8), tumor necrosis factor-alpha (TNF-alpha), soluble interleukin-2 receptor (sIL2R), and pivotal post-resuscitation syndrome (PRS) components. Cytokine dynamics were assessed before and after ECLS initiation.
Results
CPR-to-ECLS time was significantly longer in the OHCA group (p = 0.009), correlating with elevated IL6 and IL8 levels. The IHCA group showed more favorable neurological outcomes (p < 0.001), but presented with a higher incidence of multiple organ failure (p < 0.001) compared to the OHCA group. The IHCA group exhibited pronounced IL6 and IL8 levels prior to ECLS initiation significantly decreasing post-ECLS initiation (p = 0.01 and p = 0.008), whereas OHCA patients showed peak levels of IL6 and IL8 during the course of ECLS (p < 0.001).
Conclusion
IL6 and IL8 are associated with key elements of the post-resuscitation syndrome (neurological outcome, organ dysfunction and hemodynamic status) in patients undergoing eCPR for refractory cardiac arrest, possibly providing a predictive ability of organ dysfunction in OHCA patients without a preceding pro-inflammatory burden.