What is the recommended prophylaxis for Deep Vein Thrombosis (DVT)?

DVT Prophylaxis Recommendations

For hospitalized medical patients at risk for DVT, initiate prophylactic-dose LMWH (enoxaparin 40 mg subcutaneously once daily), low-dose unfractionated heparin (5,000 units subcutaneously twice or thrice daily), or fondaparinux 2.5 mg subcutaneously once daily, continued throughout hospitalization. 1

Risk Stratification and Prophylaxis Selection

Acutely Ill Medical Patients

• Standard prophylaxis options include LMWH, low-dose UFH (administered twice or thrice daily), or fondaparinux 2.5 mg once daily, continued for the duration of hospitalization (typically 6-14 days) 1
• For patients with creatinine clearance ≥30 mL/min, use LMWH or fondaparinux; for those with renal insufficiency, unfractionated heparin is preferred 1, 2
• High bleeding risk patients should receive mechanical thromboprophylaxis with graduated compression stockings and/or intermittent pneumatic compression instead of pharmacologic agents 1
• Rivaroxaban is not recommended for routine VTE prevention in acutely ill general medical patients, as it showed increased bleeding risk despite reducing VTE events 1

Surgical Patients

Orthopedic Surgery (Hip/Knee Replacement, Hip Fracture)

• Enoxaparin 30 mg subcutaneously twice daily starting 12 hours before or after surgery, continued for 10-14 days, with consideration for extension up to 35 days 1
• Fondaparinux 2.5 mg subcutaneously once daily (1.5 mg if CrCl 30-50 mL/min) starting 6-8 hours after surgery, continued for 10-14 days, with consideration for extension up to 35 days 1, 3
• For hip fracture surgery specifically, extended prophylaxis for up to 24 additional days (total 32 days) is recommended 1, 3

Non-Orthopedic Surgery

• Low-risk patients: Enoxaparin 40 mg or dalteparin 2,500 IU subcutaneously once daily 1
• High-risk patients: Dalteparin 2,500 IU 12 hours after surgery, then 5,000 IU once daily 1
• Unfractionated heparin 5,000 units subcutaneously twice or thrice daily until fully ambulatory, continued for 10-14 days, with consideration for extension up to 35 days 1, 4
• Initiate prophylaxis no earlier than 6-8 hours after surgery once hemostasis is established to minimize bleeding risk 3

Abdominal Surgery

• Fondaparinux 2.5 mg subcutaneously once daily starting 6-8 hours after surgery, continued for 5-9 days (up to 10 days in clinical trials) 1, 3
• For patients undergoing major abdominal or pelvic surgery with cancer, extended prophylaxis with LMWH for 4 weeks is recommended if bleeding risk is not high 1

Cancer Patients

Hospitalized Cancer Patients with Reduced Mobility

• LMWH or fondaparinux (if CrCl ≥30 mL/min) or unfractionated heparin for medically-treated patients 1
• Direct oral anticoagulants are not recommended routinely in this setting 1

Ambulatory Cancer Patients on Systemic Therapy

• Pancreatic cancer (locally advanced or metastatic): LMWH or direct oral anticoagulants (rivaroxaban or apixaban) for patients with low bleeding risk 1
• Khorana score ≥2 (intermediate-to-high VTE risk): Direct oral anticoagulants (rivaroxaban or apixaban) recommended if not actively bleeding or at high bleeding risk 1
• Lung cancer: Primary prophylaxis with LMWH is not recommended outside clinical trials 1
• Myeloma patients on immunomodulatory drugs with steroids: Use vitamin K antagonists (low or therapeutic doses), apixaban (prophylactic doses), LMWH (prophylactic doses), or low-dose aspirin 100 mg daily 1

Cancer Surgery

• Use highest prophylactic dose of LMWH to prevent postoperative VTE 1
• Mechanical methods alone are not recommended except when pharmacologic prophylaxis is contraindicated 1

Special Populations

Pregnant Patients

• LMWH is recommended over warfarin for both prevention and treatment of VTE throughout pregnancy 1
• Continue anticoagulation until delivery and reinitiate for at least 6 weeks postpartum (total duration ≥3 months) 1
• Fondaparinux should be avoided in pregnancy as it crosses the placenta 5

Perioperative Anticoagulation Management

• Moderate-to-high thromboembolism risk (recent VTE <3 months, active cancer): Consider bridging anticoagulation 1
• Discontinue warfarin 5 days before surgery; initiate bridging LMWH when INR <2.0, with last dose on the morning before surgery 1
• Resume warfarin the evening after surgery once hemostasis is achieved; resume therapeutic LMWH at 48 hours post-operatively, or prophylactic-dose LMWH at 12 hours post-operatively 1
• Low thromboembolism risk: Discontinue anticoagulation 5 days before procedure without bridging 1

Critical Contraindications and Warnings

• Spinal/epidural hematoma risk: Patients receiving neuraxial anesthesia or spinal puncture while on fondaparinux, LMWH, or heparinoids are at risk for long-term or permanent paralysis 3
• Risk factors include indwelling epidural catheters, concomitant NSAIDs/antiplatelet agents, history of traumatic/repeated spinal puncture, spinal deformity, or spinal surgery 3
• For epidural catheter manipulation, fondaparinux should be held 24 hours before and resumed no earlier than 2 hours after manipulation 1

Common Pitfalls to Avoid

• Inadequate prophylaxis rates: Only 58.5% of at-risk surgical patients and 39.5% of at-risk medical patients receive recommended VTE prophylaxis 1
• Premature initiation: Administering fondaparinux or LMWH earlier than 6 hours after surgery significantly increases major bleeding risk 3
• Catheter-related thrombosis: Routine anticoagulation prophylaxis for central venous catheters is not recommended; instead, ensure right-sided jugular placement with catheter tip at SVC-right atrium junction 1
• Inferior vena cava filters: Not recommended for routine prophylaxis 1