 High-dose corticosteroids attenuate the inflammatory response to surgery with CPB and are commonly used in some countries,but uncommonly in the US, Canada and Australia. Steroids can reliably attenuate activation of the complement pathways associated with cardiac surgery, but clinical trials have had mixed results. The current evidence is dominated by the results of two recent large randomized trials: DECS n4,4946 and SIRS n7,507. 