Objective: The aim of this study was to investigate the effect of systemic CPB temperature on the production of the key mediators of the systemic inflammatory response to coronary artery bypass graft (CABG) surgery.
Design: Randomized clinical study.
Setting: University hospital.
Participants: Thirty patients undergoing first-time CABG surgery.
Interventions: The patients were randomized to hypothermic (32 degrees C, n = 15) or normothermic (36 degrees C, n = 15) CPB.
Measurements and main results: Plasma interleukin (IL)-6, IL-8, IL-10, C-reactive protein (CRP), cortisol, and neutrophils were measured the day before operation, at closure of the sternum, and 4, 16, and 44 hours later. The cytokine, CRP, cortisol, and neutrophil responses were independent of temperature during CPB with peak concentrations of IL-10 at closure of the sternum followed by IL-6, IL-8, cortisol, neutrophils, and finally CRP. A correlation between maximal plasma concentrations of IL-10 and cortisol was seen in both groups after surgery (p = 0.02). Drainage after surgery was lower after normothermic CPB (p=0.02), with no difference in the requirement for blood transfusion. All patients were discharged from the intensive care unit within 24 hours after surgery.
Conclusions: The release of systemic inflammatory mediators after cardiac surgery was independent of mild hypothermia (32 degrees C) versus normothermia (36 degrees C) during CPB.