Using potent anticoagulants such as low-molecular-weight heparin to prevent
pulmonary embolism in total hip or knee arthroplasty patients, as recommended by
the Chest Physicians Consensus Statement, may actually increase the risk of
all-cause mortality compared to multimodal prophylaxis measures, according to a
systematic literature review published in Clinical Orthopaedics and Related
"We believe the American College of Chest Physicians should reconsider their
guidelines to reflect the fact that PE (pulmonary embolism) occurs despite the
use of potent anticoagulants and may, in fact, expose patients to increased
mortality after surgery," the authors said in the study.
Nigel E. Sharrock, BMedSci, MB, ChB, and colleagues at the Hospital for Special
Surgery, New York, conducted the systematic review, which included 20 English
language studies published during the last 9 years. The researchers focused on
studies that involved patients undergoing total hip arthroplasty (THA) or total
knee arthroplasty (TKA) and divided publications into three categories based on
the venous thromboembolism prophylaxis regimen.
Specifically, Group A included the use of low-molecular-weight heparin,
ximelagatran, fondaparinux or rivaroxaban, Group B included the use of a
multimodal prophylaxis, and Group C included the use of warfarin.
"Multimodal prophylaxis (Group B) was defined as a protocol consisting of
intention to use regional anesthesia (epidural or spinal) with or without
intraoperative heparin during surgery or pneumatic compression and aspirin after
surgery," the study authors noted.
The researchers found that the lowest number of deaths occurred among patients
in Group B. Patients in Groups A and C were more than two times as likely to die
compared to those in Group B, with no significant difference between Group A and
Patients in Group A also had a 60% to 70% higher risk of nonfatal PE compared to
patients in Group B.
Nonfatal PE occurred in 94 of 15,839 patients in Group A (0.6%) vs. 25 of 7,193
patients in Group B (0.35%), according to the study.
"We show clinical PE occurs despite the use of powerful anticoagulants. The rate
of 0.6% is comparable to the rate of 1% previously described with warfarin and
low-molecular-weight heparin in cohort studies.
"This literature cannot support the use of powerful anticoagulants to prevent
PE, although they clearly reduce the risk of venographically evident deep vein
thrombosis," the study authors wrote.
For more information:
Sharrock NE, Gonzalez Della Valle A, Go G, et al. Potent anticoagulants are
associated with a higher all-cause mortality rate after hip and knee
arthroplasty. Clin Orthop Relat Res. 2008;466:714-721.