%0 Journal Article
%T Biomarkers of Coagulation and Fibrinolysis during Cemented Total Hip Arthroplasty with Pre- versus Postoperative Start of Thromboprophylaxis
%A P£¿l O. Borgen
%A Ola E. Dahl
%A Olav Reikeras
%J Thrombosis
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/563217
%X Venous thrombosis is common in elective hip surgery, and prophylaxis is recommended. Clinical trials suggest that the drug dose and timing of initiating prophylaxis significantly influence antithrombotic effectiveness and safety. We studied the time course and gradient of plasma coagulation and fibrinolysis during total hip arthroplasty (THA) in twenty patients that were randomly assigned to have the first dose of 5000£¿IU dalteparin subcutaneously (sc) injected 12 hours before or 6 hours after surgery. Baseline characteristics were similar in both groups. Specific biomarkers on coagulation (prothrombin fragment 1+2 (F1+2)) and fibrinolytic activity (plasmin/¦Á2-antiplasmin complex (PAP) and D-dimer) were collected at six events during hospitalization and analysed. There were no significant group differences in the biomarkers at any time point. The highest concentrations were measured 6 hours after surgery and before the first postoperative injection. A marked decrease followed at the first postoperative day, and then a second increase in plasma concentrations was observed 6 days after surgery. This study showed that activation of coagulation and fibrinolysis by the operative trauma was the same when the first dose of dalteparin was injected 12 hours before or 6 hours after surgery. 1. Introduction Thrombosis formation begins during joint replacement surgery [1, 2], and a few patients may develop nonfatal or fatal pulmonary embolism (PE) [3]. It has been suggested that it is easier to prevent thrombus formation than to arrest thrombus growth once it has been established. Preoperative initiation of thromboprophylaxis therefore has been recommended [4, 5]. However, most thrombi develop postoperatively [6, 7], and, because anticoagulants have the potential to increase bleeding, some surgeons and anesthesiologists prefer postoperative initiation to reduce blood loss, need for transfusion, and bleeding complications [8¨C10]. Low-molecular-weight heparins (LMWHs) are widely used as antithrombotic because of their favorable efficacy-to-safety profiles and the absence of accumulated postmarketing reports on severe adverse events. Trials on timing of thromboprophylaxis have been designed to detect thrombotic events, and venographically detected DVT has been the primary end point. Bleeding has been a secondary underpowered outcome, and trials have been criticized for underestimating the risk of bleeding and related complications [11]. From surgeons point of view, blood loss and bleeding complications are important and pharmaceutical prophylaxis has remained
%U http://www.hindawi.com/journals/thrombosis/2013/563217/