It has been repeatedly demonstrated that cardiac surgery with the use of extracorporeal circulation elicits a systemic inflammatory response and provokes ischemia-reperfusion related oxidative stress which could further lead to the development of organ failure in critically ill patients. Perioperative levels of macrophage migration inhibitory factor (MIF) and other inflammatory mediators could be involved in adverse outcomes in cardiac surgery.

The trace element selenium (Se) serves as an essential co-factor for the antioxidant enzymes Thioredoxin - reductase (TRR) and many other antioxidant enzymes, which protect tissues from oxidative stress. In septic patients it has previously been shown that thioredoxin, a TRR regulated Redox Enzyme, has the ability to suppress the synthesis of MIF.

Aim of the present study is therefore to investigate the relation between perioperative selenium decrease and the reduction of TRR activity with a possible release of MIF during the inflammatory response after cardiac surgery.

Inclusion Criteria:

• more than 18 years of age
• open heart surgery and use of heart-lung-device
• informed consent has been obtained

Exclusion Criteria:

• under 18 years of age
• emergency cases
• informed consent cannot be obtained
• pregnancy or patient is breast-feeding

Patients undergoing open heart surgery and use of heart lung device