What venous thromboembolism (VTE) prophylaxis should be given to a 66-year-old patient with an intracapsular neck of femur fracture?

From the Guidelines

For a 66-year-old patient with an intracapsular neck of femur fracture, I strongly recommend venous thromboembolism (VTE) prophylaxis with low molecular weight heparin (LMWH), specifically enoxaparin 40mg subcutaneously once daily, starting preoperatively if possible and continuing for 28-35 days post-surgery, as supported by the most recent and highest quality study 1.

Rationale

The recommendation is based on the high VTE risk in hip fracture patients, particularly elderly individuals, due to the combination of tissue trauma, immobility, and age-related hypercoagulability. Hip fracture surgery patients have up to 50% risk of developing deep vein thrombosis without prophylaxis, with significant mortality risk from pulmonary embolism. Extended prophylaxis is justified because the hypercoagulable state persists during the rehabilitation period.

Key Considerations

• Renal function should be assessed before initiating LMWH, with dose adjustment needed for patients with creatinine clearance below 30 ml/min.
• Mechanical prophylaxis with graduated compression stockings or intermittent pneumatic compression devices should be added, especially if pharmacological prophylaxis is delayed.
• Alternative options, such as fondaparinux 2.5mg subcutaneously once daily, may be considered, but enoxaparin is the preferred choice based on the available evidence 1.

Evidence Summary

The study by 1 provides the most recent and highest quality evidence for VTE prophylaxis in patients with hip fracture. The study recommends enoxaparin 40mg subcutaneously once daily, starting preoperatively if possible and continuing for 10-14 days, with consideration for extension up to 35 days. This recommendation is consistent with the American College of Chest Physicians (ACCP) guidelines and is supported by the International Union of Angiology (IUA) guidelines 1.

From the FDA Drug Label

Table 9. Efficacy of Fondaparinux Sodium in the Prophylaxis of Thromboembolic Events Following Hip Replacement Surgery Endpoint Study 1 Study 2 Fondaparinux Sodium 2.5 mg SC once daily Enoxaparin Sodium 30 mg SC every 12 hr Fondaparinux Sodium 2.5 mg SC once daily Enoxaparin Sodium 40 mg SC once daily VTE 48/787 6.1% 66/797 8.3% 37/908 4.1% 85/919 9.2%

The recommended venous thromboembolism (VTE) prophylaxis for a 66-year-old patient with an intracapsular neck of femur fracture is fondaparinux sodium 2.5 mg SC once daily or enoxaparin sodium 30 mg SC every 12 hours or enoxaparin sodium 40 mg SC once daily.

• Fondaparinux sodium has been shown to have a VTE rate of 6.1% and 4.1% in two studies,
• Enoxaparin sodium 30 mg SC every 12 hours has a VTE rate of 8.3%,
• Enoxaparin sodium 40 mg SC once daily has a VTE rate of 9.2%. The choice of prophylaxis should be based on individual patient risk factors and clinical judgment 2.

From the Research

Venous Thromboembolism Prophylaxis for a 66-year-old Patient with an Intracapsular Neck of Femur Fracture

• The patient is at high risk for venous thromboembolism (VTE) due to the nature of their injury and age 3, 4, 5.
• Effective pharmacological thromboprophylaxis includes low-dose unfractionated heparin (UFH), low molecular weight heparin (LMWH), fondaparinux, and warfarin 3.
• Mechanical prophylaxis with graduated compression stockings and intermittent pneumatic compression is also recommended as an alternative or in combination with pharmacological prophylaxis 3.
• Administration of a prophylactic dose of enoxaparin on the morning of surgery does not seem to increase the rate of postoperative blood transfusion or wound drainage after fixation of geriatric femur fracture 4.
• Enoxaparin and direct oral anticoagulants (DOACs) are associated with reduced odds of VTE 5.

Recommended Prophylaxis

• Enoxaparin is a recommended option for VTE prophylaxis in patients with an intracapsular neck of femur fracture 4, 5.
• The use of fondaparinux may be associated with a higher risk of major bleeding compared to enoxaparin 6.
• It is essential to consider the patient's individual risk factors and medical history when selecting a prophylaxis option 3, 5.

Important Considerations

• The incidence of VTE following geriatric distal femur fracture fixation is relatively high, and patients with an intracapsular neck of femur fracture may be at similar or higher risk 5.
• Independent risk factors for VTE include prior VTE, displaced fracture morphologies, active cancer, coagulopathy disorder, and younger age 5.
• The use of enoxaparin or DOACs may be effective in mitigating the risk of VTE in these patients 5.