Aspirin for VTE prophylaxis following total hip or knee replacement

Aspirin for venous thromboembolism (VTE) (ie deep vein thrombosis [DVT] or pulmonary embolism [PE]) prophylaxis should only be considered following a total hip or knee replacement, for patients at low risk of VTE (eg patients without any of the risk factors listed in Risk factors for VTE in nonsurgical patients in hospital). These patients must have already received 5 days of rivaroxaban therapyAnderson, 2018.

Do not use aspirin for VTE prophylaxis for surgeries other than total hip or knee replacement in patients at low risk—aspirin is not as effective as anticoagulants. In a randomised controlled trial of patients undergoing total hip or knee replacement, the use of aspirin alone showed an increased risk of symptomatic VTE compared to enoxaparin¹ Cristal Study Group, 2022.

If aspirin is appropriate, it may be started after at least 5 days of rivaroxaban therapy to complete the courseAnderson, 2018 Anderson, 2019. Some clinicians use mechanical prophylaxis in conjunction with aspirin.

Evidence to guide VTE prophylaxis with aspirin is limited and practice varies; consult local protocols. If a local protocol is unavailable and aspirin is considered more appropriate than an anticoagulant, use:

aspirin 75 mg to 150 mg orally, once daily. aspirin aspirin aspirin

¹ CRISTAL Study Group, Sidhu VS, Kelly TL, Pratt N, Graves SE, Buchbinder R, et al. Effect of Aspirin vs Enoxaparin on Symptomatic Venous Thromboembolism in Patients Undergoing Hip or Knee Arthroplasty: The CRISTAL Randomized Trial. JAMA 2022;328(8):719-27. URL Return