Evidence suggests fondaparinux is more effective than LMWH in prevention of VTE and total DVT in the postoperative setting



Clinical question: How do pentasaccharides compare to other anticoagulants in postoperative venous thromboembolism prevention?

Background: Venous thromboembolism (VTE) remains a leading cause of preventable hospital related death. Pentasaccharides selectively inhibit factor Xa to inhibit clotting and exhibit a lower risk of heparin induced thrombocytopenia (HIT) compared to low molecular weight heparin (LMWH) and unfractionated heparin. We lack a formal recommendation regarding the pentasaccharides superiority or inferiority, relative to other anticoagulants, in the perioperative setting.

Study design: Cochrane review.

Setting: Hospital and outpatient.

Synopsis: Authors searched randomized controlled trials involving pentasaccharides versus other VTE prophylaxis to obtain 25 studies totaling 21,004 subjects undergoing orthopedic, abdominal, cardiac bypass, thoracic, and bariatric surgery; hospitalized patients, immobilized patients, and those with superficial venous thrombosis. Selected studies pertained to fondaparinux and VTE prevention. Fondaparinux was superior to placebo in prevention of DVT and VTE. Compared to LMWH, fondaparinux reduced total VTE (RR, 0.55, 95% CI, 0.42-0.73) and DVT (RR, 0.54, 95% CI, 0.40-0.71), but carried a higher rate of major bleeding compared to placebo (RR, 2.56, 95% CI, 1.48-4.44) and LMWH (RR, 1.38, 95% CI, 1.09-1.75). The all cause death and major adverse events for fondaparinux versus placebo and LMWH were not statistically significant. Limitations of this review include the predominance of orthopedic patients, variable duration of treatment, and low-moderate quality data.

Bottom line: Fondaparinux demonstrates better perioperative total VTE and DVT reduction compared to LMWH, but it increases the incidence of major bleeding.

Reference: Dong K, Song Y, Li X, Ding J, Gao Z, Lu D, Zhu Y. Pentasaccharides for the prevention of venous thromboembolism. Cochrane Database Syst Rev. 2016 Oct 31;10:CD005134.

Dr. Coleman is an assistant professor of clinical medicine at Cooper Medical School at Rowan University. She works as a hospitalist at Cooper University Hospital in Camden, N.J.