All adult patients requiring ECMO will be considered for the trial, with a target enrollment of 50 participants over a two-year period. For each enrolled participant, a TEG transfusion algorithm will be followed for patients exhibiting inadequate hemostasis in the operating room (Flowchart 1). Once patient has a normal TEG result with adequate hemostasis, either heparin or bivalirudin will be used as the anticoagulant. If patients are receiving no anticoagulation or heparin anticoagulation then a second TEG algorithm will be followed in the ICU when hemostasis is normal and heparin is introduced (Flowchart 2). If patients are receiving bivalirudin as their anticoagulation strategy, the transfusion parameters with TEG application will not apply. In addition to determining the compliance and feasibility of following these TEG algorithms, clinical outcome data including transfusion rates, types of blood products transfused, estimated blood loss and thrombotic events will be collected for every enrolled patient until they are discontinued from ECMO. Statistical analysis of the primary, secondary and tertiary endpoints of this study will determine the likelihood of exploring future clinical trials involving TEG-driven coagulation and transfusion management of the ECMO population.