Hip joint replacement surgery, using acrylic cement for prosthesis fixation, is associated with intraoperative cardiorespiratory dysfunction, and a high frequency of postoperative proximal deep vein thrombosis (DVT). Levels of prothrombin fragments 1+2 (F1+2), tissue plasminogen activator antigen (t-PA), plasminogen activator inhibitor 1 activity (PAI-1), D-dimer and interleukin 6 (IL-6) were measured in arterial (AB) and mixed venous blood (MVB) in five patients during and after total hip replacement operation with acrylic cement prosthesis fixation. Sequential peaks of F1+2, t-PA, PAI-1 and IL-6 appeared, starting with activation of coagulation during preparation of bone, closely followed by activation of fibrinolysis. Later, this was counteracted by an antifibrinolytic response and increase of IL-6. After a fibrinolytic shutdown on the third postoperative day as evidenced by a drop in t-PA and D-dimer concentrations, a second wave of coagulation was seen at the end of the first week. The present model, with frequent sampling of blood entering and leaving the lungs, confirms our earlier findings of the lung as a key organ in promoting coagulation following traumatic activation.