Efficacy of prevention of thromboembolic complications with LMW-heparin in experiment

The authors used an antithrombotic agent (Nadroparin Calcium) with anti-Xa effect in their experiments to prevent thromboembolic complications in the model of endoprosthetic replacement of the hip joint in mongrel dogs. 10 experimental animals (Group I.) were given doses of 100 A Xa ICU/kg/bwt of Nadroparin Calcium subcutaneously 4 hours prior to the operation and also once a day until the 3rd postoperative day; between the 4th and 10th postoperative days doses of 150 A Xa ICU/kg/bwt Nadroparin Calcium were given. The 10 control animals (Group II.) did not receive anticoagulant treatment. In both groups platelet count, activated partial thromboplastin times (APTT), prothrombin and fibrinogen levels as well as activated factor X inhibition (F Xa) were measured prior to surgery and also until the 14th postoperative day. No changes in APTT and prothrombin levels were detected during the experiment, however platelet count and fibrinogen levels as well as the extent of F Xa inhibition showed significant and different changes in groups I. and II. The Group I. which had received thromboembolic prophylaxis did not develop deep venous thrombosis or pulmonary embolism, but the control group did. Based on their investigations, the authors concluded that they had been able to achieve F Xa inhibition by giving the above mentioned doses of Nadroparin Calcium which was enough to prevent thromboembolic complications in their model experiment of implanting hip endoprosthesis.