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Prolonged thromboprophylaxis after hip-replacement surgery decreases VTE

Clinical Question:
What is the optimal duration of thromboprophylaxis after major orthopedic surgery?

Bottom Line:
The use of prolonged thromboprophylaxis (21 days or longer), as compared with the standard duration of 7 days to 10 days, reduces the risk of venous thromboembolism (VTE) while increasing the risk of minor bleeding in patients who have undergone major orthopedic surgery. The majority of the patients in this study had total hip replacement, so the findings are mainly applicable to that population. (LOE = 1a)

Sobieraj DM, Lee S, Coleman CI, et al. Prolonged versus standard-duration venous thromboprophylaxis in major orthopedic surgery. Ann Intern Med 2012;156(10):720-727.  [PMID:22412039]

Study Design:
Meta-analysis (randomized controlled trials)



Inpatient (any location) with outpatient follow-up

These investigators searched MEDLINE and the Cochrane Register, as well as references from relevant studies, to find randomized controlled trials that compared prolonged (21 days or longer) with standard (7-10 days) venous thromboprophylaxis in patients undergoing hip fracture surgery or total knee or hip-replacement surgery. Two authors independently extracted data and assessed study quality and strength of evidence. Of the 8 trials selected, 6 exclusively enrolled patients with total hip replacement. The mean ages of patients enrolled in all 8 trials ranged from 63 years to 79 years. High strength of evidence showed that patients who received prolonged thromboprophylaxis had decreased rates of pulmonary embolism (odds ratio [OR] = 0.14; 95% CI, 0.04-0.47) and fewer symptomatic deep venous thromboses (OR = 0.36; 0.16-0.81), but higher rates of minor bleeding (OR = 2.44; 1.41-4.20). Moderate strength of evidence showed that the risk of symptomatic VTE overall was reduced with prolonged prophylaxis. There was no difference in major bleeding between the 2 groups, though the strength of this evidence was rated as low.


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