Comparison of 3,000 IU aXa of the low molecular weight heparin certoparin with 5,000 IU aXa in prevention of deep vein thrombosis after total hip replacement. German Thrombosis Study Group.

BACKGROUND

The aim of this randomized, double-blind and prospective clinical trial was to investigate whether an increase of the conventional daily dosage (3,000 IU aXa) of the low molecular weight heparin certoparin up to 5,000 IU aXa/day might lower the incidence of deep vein thrombosis (DVT) in patients undergoing elective hip surgery.

METHODS

The main criterium of this trial was the incidence of DVT diagnosed by bilateral ascending venography, which was performed either if DVT was clinically suspected or in each remaining patient between the 12th and the 14th postoperative day. A total number of 172 patients were enrolled to receive the conventional dosage of 3,000 IU aXa (Mono-Embolex NM) and 169 patients to receive the high dosage form (5,000 IU aXa) once daily. The mean age (+/-SD) was 69.6+/-9.5 and 67+/-11.7 years.

RESULTS

No relevant differences were found concerning predisposing risk factors. The duration of surgery was 93+/-25.2 and 88+/-21.4 min (mean+/-SD). Surgical type and approach were not different between the groups. Deep vein thrombosis was detected in 17 patients (9.9%) in the conventional dose group and in 16 patients (9.5%) in the high dose group (intent-to-treat analysis; n.s.). The rate of bleeding complications was not significantly different except the cell saver volumes (770+/-136 vs 475+/-186 ml; p<0.001). No significant difference was found in the serious adverse event reporting along the lines of EC-GCP (10 vs 8 events; p=0.65).

CONCLUSIONS

This clinical trial confirmed that the conventional dosage (3,000 IU aXa/day) of certoparin ensures maximal antithrombotic activity.