[Prophylaxis for deep vein thrombosis with low molecular weight heparin following hip and knee surgery].

OBJECTIVE: To evaluate the efficacy and safety of low molecular weight heparin(LMWH) in prophylaxis of postoperative deep vein thrombosis (DVT) following hip and knee surgery. METHODS: From April 1997 to October 1998, 46 patients undergoing hip and knee orthopedic procedures were randomized into 2 groups for studying. The following eligibility criteria were applied: age over 40 years old, no recently history of venous thromboembolism (over 3 months), normal result of preoperative hemostasis test and normal result of Doppler examination of the lower extremities. One group was control group and the other group received subcutaneously a low molecular weight heparin(Fraxiparine) with anti-factor X, activity of 41 IU/kg.day for three days, then 62 IU/kg.day from the 4th day to 10th day. All patients had venegraphy performed in the operated leg at 4 to 7 days after surgery. RESULTS: eight patients(34.8%) developed DVT in the control group of 23 patients and 1 patient (4.3%) in the experimental group, also of 23 patients(P < 0.05). Two groups had no any bleeding complications. CONCLUSION: The low molecular weight heparin is safe and effective in preventing postoperative deep vein thrombosis in patients following hip and knee surgery.