[Prevention of thromboembolism in patients operated on for hip prosthesis]

The latest research into the prevention of peri- and postoperative thromboembolic disease has found orthopaedic surgery patients to be most at risk. As the genesis of deep venous thrombosis (DVT) is due to haemodynamic, hemorheologic and parietal factors, various prophylactic measures have been considered in the past, measures which have not proved able to provide satisfactory protection in orthopaedics. The results obtained with Defibrotide in a random and controlled clinical study versus calcium heparin involving 211 patients of both sexes candidates to receive total hip arthroplasty and presenting at least one major thromboembolic risk factor are reported. The patients were assigned at random to one of the following treatments: 1) Defibrotide at a dose of 400 mg b.i.d. i.v. in 50 ml phleboclysis in 5 minutes (n = 108); 2) calcium heparin at a dose of 5000 IU t.i.d. subcutaneously (n = 103). The treatment began the day before operation and continued on average up to the eighth day for the Defibrotide group. With the control group it continued until discharge (usually on the 15th day) and at home for about three weeks until the completion of the physiotherapy cycle. In the 108 patients treated with Defibrotide only one case of DVT was reported and in none of these patients were symptoms or signs of pulmonary embolism encountered. In the group treated with calcium heparin 2 cases of clinically and radiologically diagnosed pulmonary embolism and 4 cases of DVT were observed. Although the differences were not statistically significant, the tendency favours Defibrotide. Statistically significant (p less than 0.01) was the difference in postoperative bleeding evaluated with particular attention in patients of advanced age. Further, in the Defibrotide group, scarring was considered excellent in 96% of cases while in the heparin group scarring was excellent in 85% (p less than 0.05). To conclude, the sure clinical effectiveness, tolerance, handiness and lack of interference with clotting functions make Defibrotide a really useful drug for the prevention of thromboembolic episodes in patients undergoing major orthopaedic surgery.