[Prevention of deep vein thrombosis by enoxaparin after total hip prosthesis]

Abstract

Once daily dosing of Enoxaparin to prevent deep vein thrombosis (DVT) after total hip replacement has been defined through two double-blind prospective, randomized multicentric trials. A previous prospective study including 228 consecutive patients had determined optimal dose to be 40 mg daily (4000 anti Xa U) begun 12 hours pre-operatively. The first trial (118 patients) compared two modes of administration of the dose of 40 mg--either 40 mg once daily or 20 mg twice daily, every twelve hours. Results were a figure of 6% for total DVT detected by ascending bilateral phlebography, 5% of wound hematoma and did not shown a statistically significant difference between the two modes of administration as regard tolerance. The second trial (237 patients) compared unfractionated calcic Heparin (5000 U.I. every eight hourly begun two hours before surgery) with Enoxaparin, 40 mg/day begun twelve hours before surgery. In the unfractionated Heparin group, we observed 27 total DVT (25%) 20 proximal DVT (12.5%) and one case of non fatal pulmonary embolism. In the Enoxaparin group, we observed 15 total DVT (12.5%), 9 proximal DVT (7.5%) no case pulmonary embolism. Red-cell transfusion requirements and hemoglobin levels on the third post-operative day shown a significant better tolerance in the Enoxaparin group. Theses results are coherent with those observed in the placebo controlled trial of Turpie, Levine, et al (1986). They used a dose of 30 mg twice daily (6000 anti Xa IU) begun 12/24 hours post-operatively, and observed a figure of 12% for total DVT and 4% for proximal DVT. Tolerance was the same than in the placebo group.