Persistence of hypercoagulability status after hip and knee orthopedic replacement: what is the optimal duration of antithrombotic guidelines in thissurgery?

Among 79 patients candidates to hip (53) and knee (26) replacement an evalu ation was made of the influence of a two-week program with LMWH on the evol ution of hypercoagulability markers: D-D, TAT, and F1+2. Measurements were performed by ELISA preoperatively and on days 1, 7 and about 45 postoperati vely; in the latter, two extraction intervals were considered: less than or equal to 45 days and > 45 days. With both surgical modalities, D-D and F12 peaked at 7th day postoperatively, whereas TAT peaked on day 1. Among D-D and F1+2 values quantitated on day 7th and the extraction interval less th an or equal to 45 days, no significant differences were obtained (Z < 2.64) . The hypercoagulative chronicity exhibited by D-D and F1+2 during the first month and a half after this surgery, might require in some cases a more pro longed thromboprophylaxis.