Postoperative interleukin-8 levels are related to the duration of coronary artery bypass grafting surgery and predict in-hospital postsurgical complications

Introduction : The magnitude of the very early coronary artery bypass grafting (CABG)-related inflammatory response has been shown to influence post-CABG outcomes. However, the dynamics of the systemic inflammatory response to CABG beyond the very early postoperative phase and its relevance to clinical outcomes are not fully understood. Methods : Circulating levels of several inflammatory markers were determined in 30 consecutive patients undergoing elective isolated on-pump CABG one day prior (D0-1), and 2 (D2) and 5 days post-CABG. Results : CABG was associated with a significant increase in all studied inflammatory marker levels (all p<0.05 for D2 versus D0-1). D2 post-CABG IL-6 and IL-8 levels were both significantly positively correlated with extracorporeal circulation (ECC) and aortic clamping (AC) times (all p<0.05), whereas a weaker correlation was observed between D2 post-CABG IL-8 levels and total surgery time (r=0.42, p=0.02). In multiple regression analysis, D2 IL-8 levels independently predicted post-CABG kidney (p= 0.02) and liver (p = 0.04) dysfunction, as well as a sum of post-CABG major complications ≥2 (p = 0.04). Conclusions : In this prospective study, longer duration of cardiopulmonary bypass caused a larger post-CABG inflammatory surge, whereas the duration of total CABG surgery had a less significant effect. IL-8 hyperresponders had greater risk of developing kidney and liver dysfunction and presented more major post-CABG complications. These data suggest that targeting the IL-8 pathway using antiinflammatory agents, or simply by shortening the duration of cardiopulmonary bypass could improve the in-hospital post-CABG outcomes in this population.