Short-duration prophylaxis against XXXX after total hip or knee replacement: a meta-analysis of prospective studies investigating symptomatic outcomes.

@entity1 @entity1151 @entity1150 @entity1211 @entity1229
BACKGROUND: The prevalence of asymptomatic @entity1150 diagnosed by venography after hip or knee replacement remains high despite 7 to 10 days of anticoagulant prophylaxis. However, the risk of symptomatic events in such @entity1 is unclear. We performed a meta-analysis to provide reliable estimates of the risk of symptomatic @entity1211 occurring within 3 months of hip or knee replacement in @entity1 who received short-duration (7-10 days) anticoagulant prophylaxis. METHODS: The MEDLINE, EMBASE, and Cochrane databases were searched from January 1993 to March 2001, supplemented by a manual search of bibliographies and conference abstracts, to identify prospective studies of @entity1 undergoing hip or knee replacement who received short-duration prophylaxis (ie, 7-10 days of fixed-dose low-molecular-weight heparin or adjusted-dose @entity1229 , with a target international normalized ratio of 2.0-3.0). Studies were classified as clinical outcome studies if the outcome was symptomatic @entity1211 or as venographic outcome studies if the outcome was asymptomatic @entity1150 diagnosed after bilateral venography. RESULTS: There were 4 clinical outcome studies with 6089 @entity1 who had 3 months of follow-up, and 13 venographic outcome studies with 7080 @entity1 who had venography 7 to 10 days after surgery. In clinical outcome studies, the 3-month incidence of @entity1211 was 3.2% (95% confidence interval [CI], 2.0%-4.4%), and the 3-month incidence of @entity1151 was 0.10% (95% CI, 0.02%-0.20%). The postprophylaxis incidence of @entity1211 was 2.2% (95% CI, 1.4%-3.0%), and the incidence of @entity1151 was 0.05% (95% CI, 0%-0.12%). The postprophylaxis incidence of symptomatic @entity1211 was higher after hip than after knee replacement (2.5% vs 1.4%; P=.02). In venographic outcome studies, the prevalence of @entity1150 (total and proximal) was higher after knee than after hip replacement (total: 38.8% vs 16.4%; P<.001; proximal: 7.6% vs 3.8%; P<.001). CONCLUSIONS: In @entity1 who undergo hip or knee replacement and receive short-duration anticoagulant prophylaxis, symptomatic @entity1211 will occur in about 1 of 32 @entity1 and @entity1151 will occur in about 1 of 1000 @entity1 within 3 months of the surgery. Although the prevalence of asymptomatic @entity1150 is more than 2-fold higher after knee replacement than after hip replacement 7 to 10 days after surgery, in the subsequent 3 months, symptomatic @entity1211 is more likely to occur after hip replacement.
