The Effects of Steroids on Coagulation Dysfunction Induced by Cardiopulmonary Bypass: A Steroids in Cardiac Surgery (SIRS) Trial Substudy

Cardiopulmonary bypass (CPB) surgery, despite heparin administration, elicits activation of coagulation system resulting in coagulopathy. Anti-inflammatory effects of steroid treatment have been demonstrated, but its effects on coagulation system are unknown. The primary objective of this study is to assess the effects of methylprednisolone on coagulation function by evaluating thrombin generation, fibrinolysis, and platelet activation in high-risk patients undergoing cardiac surgery with CPB. The Steroids In caRdiac Surgery study is a double-blind, randomized, controlled trial performed on 7507 patients worldwide who were randomized to receive either intravenous methylprednisolone, 250 mg at anesthetic induction and 250 mg at initiation of CPB (n = 3755), or placebo (n = 3752). A substudy was conducted in 2 sites to collect blood samples perioperatively to measure prothrombin fragment 1.2 (PF1+2, thrombin generation), plasmin-antiplasmin complex (PAP, fibrinolysis), platelet factor 4 (PF4 platelet activation), and fibrinogen. Eighty-one patients were enrolled in the substudy (37 placebo vs 44 in treatment group). No difference in clinical outcome was detected, including postoperative bleeding and need for blood products transfusion. All patients showed changes of all plasma biomarkers with greater values than baseline in both groups. This reaction was attenuated significantly in the treatment group for PF1.2 (P = 0.040) and PAP (P = 0.042) values at the first intraoperative measurement. No difference between groups was detected for PF4. Methylprednisolone treatment attenuates activation of coagulation system in high-risk patients undergoing CPB surgery. Reduction of thrombin generation and fibrinolysis activation may lead to reduced blood loss after surgery.