Efficacy of fixed minidose warfarin prophylaxis in total hip replacement

Abstract

Objective - To determine whether a small fixed perioperative dose of warfarin would prevent deep vein thrombosis after total hip replacement. Design - Prospective, randomised, double blind placebo controlled trial. Setting - Winford Orthopaedic Hospital, Bristol. Subjects - 148 patients having primary total hip replacement. Intervention - Warfarin 1 mg given daily for one week before and three weeks after surgery. Main outcome measure - Deep vein thrombosis diagnosed by the iodine-125 labelled fibrinogen uptake method. Results - Deep vein thrombosis occurred in 25 (34%) of the patients given warfarin and 19 (26%) of the controls (difference 8%; 95% confidence interval -6-8% to 22-8%). Conclusion - Fixed minidose warfarin does not prevent deep vein thrombosis after total hip replacement.