Venous thromboembolism after fracture and its prophylaxis

What it is

Venous thromboembolism is common after pelvis and lower fractures, and it is the 3rd cause of death after 24 hours of trauma. Its pathophysiology is Virchow's triad.

Its pathogenesis runs in a set order: it starts soon after injury; the clot is unstable in weeks 1-3; and PE may start de novo, so it need not begin as a clot that moved up from the leg.

One number follows from that and is worth holding: only 1/3 of PE patients have DVT found.

Which fractures carry the risk

Most frequent after:

• Hip fractures
• Pelvis and acetabulum
• Femur and around the knee

A fracture below the knee has lower possibility for VTE, so where the fracture sits on the limb is itself part of the risk.

Risk factors

• Spinal injury with paraplegia
• ICU admission
• Surgery more than 2 hours
• Prolonged immobilization
• Thrombophilia
• Pregnancy
• Obesity
• Active malignancy
• Smoking