Can Aspirin (acetylsalicylic acid) be used as Deep Vein Thrombosis (DVT) prophylaxis?

From the Guidelines

Aspirin can be used as Deep Vein Thrombosis (DVT) prophylaxis, particularly in patients who are at high risk of bleeding or have contraindications to traditional anticoagulants.

Key Points

• The use of aspirin for DVT prophylaxis is supported by clinical guidelines, such as the 2021 Chest guideline, which suggests aspirin over no aspirin to prevent recurrent VTE in patients with an unprovoked proximal DVT or PE who are stopping anticoagulant therapy and do not have a contraindication to aspirin 1.
• Aspirin's role in DVT prevention is thought to be most effective when used in combination with other preventive measures, such as mechanical prophylaxis or in patients who are at low to moderate risk of DVT.
• The recommended dose of aspirin for DVT prophylaxis is 75 mg or 150 mg daily, as suggested by the 2020 NICE guideline 1.
• Aspirin has been shown to be less effective at preventing recurrent VTE than anticoagulants, but may be considered in patients who have decided to stop anticoagulants or have contraindications to anticoagulant therapy 1.
• The use of aspirin for DVT prophylaxis should be balanced against its risk of bleeding and inconvenience, and should be reevaluated when patients stop anticoagulant therapy 1.

The FDA Drug Labels for aspirin (PO) do not address this question.

From the Research

Aspirin as DVT Prophylaxis

• Aspirin has been studied as a potential prophylaxis for Deep Vein Thrombosis (DVT) in various patient populations, including trauma patients and those undergoing orthopedic surgery 2, 3, 4, 5, 6.
• The evidence suggests that aspirin may be effective in reducing the incidence of DVT, particularly when used in combination with other prophylactic measures such as heparinoid prophylaxis or mechanical devices 2, 3, 6.
• A study published in 2016 found that preinjury aspirin use was associated with a significant protective effect against DVT in trauma patients, with an odds ratio of 0.17 (95% confidence interval, 0.04-0.68; p = 0.012) 2.
• Another study published in 1986 found that aspirin was effective in preventing DVT in patients undergoing total hip replacement, with a significant reduction in phlebographic DVT compared to the control group 3.
• A 2009 review of randomized controlled trials found that aspirin was efficacious in preventing VTE compared to placebo or no treatment, but appeared to be less efficacious than low molecular weight heparins in small trials 4.
• A 2023 meta-analysis found that aspirin combined with mechanical devices had a comparable risk of DVT to low molecular weight heparin, and suggested that aspirin combined with mechanical devices may be a suitable option for VTE prophylaxis in patients after orthopedic surgery 6.

Comparison to Other Prophylactic Measures

• Aspirin has been compared to other prophylactic measures such as low molecular weight heparin (LMWH) and heparin-dihydroergotamine (heparin-DHE) in various studies 3, 4, 6.
• The evidence suggests that aspirin may be less efficacious than LMWH in preventing DVT, but may be a suitable alternative in certain patient populations or when used in combination with other prophylactic measures 4, 6.
• A study published in 1986 found that aspirin was more effective than heparin-DHE in preventing phlebographic DVT in patients undergoing total hip replacement 3.

Clinical Implications

• The use of aspirin as DVT prophylaxis may be considered in certain patient populations, such as those undergoing orthopedic surgery or trauma patients 2, 3, 5, 6.
• Aspirin may be a suitable alternative to other prophylactic measures such as LMWH in certain situations, such as when there is a high risk of bleeding or when LMWH is contraindicated 4, 6.
• Further studies are needed to fully evaluate the efficacy and safety of aspirin as DVT prophylaxis in different patient populations and to determine the optimal dosing and duration of therapy 2, 4, 6.