Is Deep Vein Thrombosis (DVT) prophylaxis needed in elderly patients with a femur fracture who are not undergoing surgery?

DVT Prophylaxis for Non-Operative Femur Fractures in Elderly Patients

Yes, DVT prophylaxis is strongly recommended for elderly patients with femur fractures even when not undergoing surgery, as these patients face substantial thrombotic risk from the fracture itself, advanced age, and immobility. 1, 2

Risk Assessment

Elderly patients with femur fractures carry multiple high-risk factors that mandate prophylaxis:

• Age ≥65 years alone contributes 2 points on the validated Trauma Embolic Scoring System (TESS), and age >75 is an independent DVT risk factor 1, 2
• Lower extremity fractures add 2 additional points to the TESS score 1
• This combination typically places patients in moderate-to-high risk category (TESS ≥3), warranting prophylaxis 1
• Preoperative DVT rates in femur fractures reach 18.9-62% depending on delay to treatment, with most occurring in the fractured limb 3, 4
• Without extended prophylaxis, VTE rates reach 12-37% in hip fracture patients 1, 2

Additional risk factors that further elevate thrombotic risk include:

• Prolonged bed rest >7 days 3
• Multiple fractures 3
• Coexisting movement disorders 3
• Elevated D-dimer and fibrinogen levels 3

Pharmacological Prophylaxis Recommendations

Low molecular weight heparin (LMWH) is the preferred agent:

• Enoxaparin 30 mg subcutaneously every 12 hours is the recommended dosing 1, 2
• LMWH demonstrates superior efficacy over unfractionated heparin with 32% additional DVT reduction (RR 0.68), plus fewer bleeding complications and lower mortality 1, 2
• Dose adjustment according to anti-Xa levels and patient weight is warranted 1, 2
• In renal failure, switch to unfractionated heparin 5000 units every 8 hours to avoid drug accumulation 1, 2

The 2023 World Society of Emergency Surgery guidelines specifically recommend administering VTE prophylaxis with LMWH or UFH as soon as possible in high and moderate risk elderly trauma patients (strong recommendation, 1C evidence). 1

Mechanical Prophylaxis

Mechanical prophylaxis should be added to pharmacological prophylaxis whenever possible:

• Combined mechanical and pharmacological prophylaxis reduces DVT risk by 66% (RR 0.34) compared to no prophylaxis 1, 2
• Options include intermittent pneumatic compression devices, graduated compression stockings, and early mobilization 1, 2
• If pharmacological prophylaxis is contraindicated, mechanical prophylaxis alone reduces DVT risk by 45% (RR 0.55) 1, 2

Timing and Contraindications

Initiate prophylaxis as soon as possible unless specific contraindications exist:

Delay pharmacological prophylaxis for 24 hours in patients with: 1

• Active bleeding
• Coagulopathy
• Hemodynamic instability
• Solid organ injury
• Traumatic brain injury (hold until CT shows no progression) 1
• Spinal trauma requiring stabilization

Use mechanical prophylaxis during the delay period if pharmacological agents are contraindicated 1

Duration of Prophylaxis

For non-operative management, continue prophylaxis throughout the period of immobility:

• Standard duration is minimum 5-9 days for most fracture patients 2
• Extended prophylaxis may be needed for up to 5 weeks given the continuing risk related to immobility, particularly in hip fractures 1, 2
• The risk of DVT persists for up to 2 months following hip fractures in immobilized patients 1

Special Considerations for Non-Operative Patients

Non-operative femur fracture patients face unique challenges:

• Delay to treatment is a major independent risk factor - 62% of patients with >48 hour delay developed preoperative DVT regardless of age, fracture type, or comorbidities 4
• Recent antiplatelet drug use and prophylactic anticoagulation decrease VTE risk (OR 0.424 and 0.503 respectively) 3
• Comprehensive prophylaxis (aspirin, fibrinolytic enzyme, passive/active foot exercises) reduced DVT incidence from 48% to 4.9% in one study of elderly proximal femur fractures 5

Common Pitfalls

• Do not withhold prophylaxis based solely on non-operative status - the fracture and immobility create substantial thrombotic risk independent of surgery 1, 3, 4
• Do not assume low-risk based on age alone - elderly patients with lower extremity fractures automatically qualify as moderate-to-high risk 1
• Monitor for bleeding complications but recognize that LMWH has lower bleeding rates than UFH 1
• Neither mechanical nor pharmacological prophylaxis significantly reduces PE rates in meta-analyses, but DVT prevention remains critical for morbidity reduction 1, 2