Deep Vein Thrombosis Prevention

1. See Also
   1. DVT in Pregnancy
   2. DVT Prevention in Travelers
   3. Low Molecular Weight Heparin
   4. Perioperative Anticoagulation
2. Precuations: Venous Thromboembolism Risk Reduction
   1. Early mobilization after surgery is critical
   2. Perioperative risk of VTE varies by surgery, anesthesia
   3. Decision to anticoagulate is individualized to patients
      1. Does the risk of bleeding outweigh the VTE Risk
3. Management: General
   1. Anticoagulation start varies per medication and risk
   2. Continue Anticoagulation for at least 10 days post-orthopedic surgery
   3. Indications for extended Anticoagulation (28-35 days)
      1. Total hip replacement
      2. Hip Fracture
      3. Other risk factors
         1. Obesity
         2. Prior Venous Thromboembolism
         3. Immobility
         4. Advanced age
         5. Comorbid active malignancy
4. Management: Perioperative protocol for the Highest Risk Patients
   1. Criteria
      1. Major surgery in high risk patient over age 40 years
         1. Venous Thromboembolism
         2. Cancer
         3. Thrombophilia
      2. Surgery at highest risk of thromboembolism
         1. Hip or knee arthroplasty
         2. Hip Fracture surgery
         3. Major surgery
         4. Acute spinal cord injury
   2. Management
      1. Anticoagulation options
         1. Low Molecular Weight Heparin
            1. Enoxaparin (Lovenox)
               1. Start: 40 mg SC 1-2 hours before surgery
               2. Then: 30 mg SC q12 hours (8-12 hours post-op)
            2. Dalteparin (Fragmin)
               1. Start: 5000 units SC 8-12 hours pre-op
               2. Then: 5000 units SC daily
         2. Warfarin with target INR 2-3
         3. Unfractionated Heparin 5000 units q8-12 hours
         4. Weight based Heparin nomogram
         5. Aspirin (not a first-line agent)
            1. Chest guidelines approved Aspirin for use as of 2012 in total knee arthroplasty or total hip arthroplasty (as alternative agent)
            2. However, Low Molecular Weight Heparin prevents 11 more major VTE events than Aspirin per 1000 patients when used for 35 days
            3. Dose 162 mg daily for at least 10-14 days (preferably 35 days in hip or knee replacement)
            4. (2012) Presc Lett 19(3): 16
      2. Additional strategies (with Anticoagulation)
         1. Intermittent Pneumatic Compression stockings or
         2. Graduated Compression stockings or
         3. Foot and calf pumping devices
   3. Special circumstances: Hip Fracture protocol
      1. Fondaparinux is preferred
      2. Heparin or LMWH started pre-operatively
         1. Delay 12-24 hours post-op if bleeding high-risk
      3. Continue LMWH, Warfarin or Fondaparinux post-op
         1. Continue for at least 10-14 days after surgery
         2. Consider continuing for 28 to 35 days post-op
   4. Special circumstances: Elective hip surgery
      1. Lose weight before surgery
      2. Ambulation before the second post-surgical day
   5. Special circumstances: Gynecologic Surgery
      1. Unfractionated Heparin is the preferred agent
5. Management: Perioperative for High Risk Patients
   1. Criteria
      1. Patient with thromboembolism risk and
         1. Age over 60 years and nonmajor surgery or
         2. Age over 40 years and major surgery
   2. Management
      1. Low Molecular Weight Heparin or
         1. Enoxaparin (Lovenox)
            1. Start: 40 mg SC 1-2 hours before surgery
            2. Then: 30 mg SC q12 hours (8-12 hours post-op)
         2. Dalteparin (Fragmin)
            1. Start: 5000 units SC 8-12 hours pre-op
            2. Then: 5000 units SC daily (12-24 hours post-op)
      2. Unfractionated Heparin 5000 units q8-12 hours or
      3. Intermittent Pneumatic Compression stockings
6. Management: Perioperative for Moderate Risk Patients
   1. Criteria
      1. Orthopedic Surgery (40-60% thromboembolism risk)
      2. Thromboembolism risk and minor surgery
      3. No thromboembolism risk
         1. Age over 60 years and nonmajor surgery or
         2. Age over 40 years and major surgery
   2. Management
      1. Low Molecular Weight Heparin (preferred) or
         1. Enoxaparin (Lovenox)
            1. 30 mg SC q12 hours (start 12-24 hours post-op) or
            2. 40 mg SC daily (start 12 hours post-op)
         2. Dalteparin (Fragmin)
            1. Start: 5000 units SC 8-12 hours pre-op
            2. Then: 5000 units SC daily (12-24 hours post-op)
         3. Tinzaparin (Innohep)
            1. Start: 3500 units SC 2 hours before surgery
            2. Then: 3500 units SC daily
      2. Unfractionated Heparin 5000 units q8-12 hours or
      3. Intermittent Pneumatic Compression stockings or
   3. Special Circumstances: Total Knee Replacement
      1. Low Molecular Weight Heparin is preferred
7. Management: Perioperative for Low Risk Patients
   1. Criteria
      1. Minor surgery in age <40 and no thromboembolism risk
   2. Management
      1. No Anticoagulation
      2. Early mobilization
      3. Consider graduated Compression stockings
8. Management: Other indications for prophylaxis
   1. Major trauma or acute spinal cord injury
      1. Assumes patient is hemodynamically stable
      2. Start 12 to 24 hours after injury
      3. Enoxaparin (Lovenox) 30 mg SC every 12 hours
   2. Long leg cast above knee (especially in elderly)
      1. Kock (1995) 346:459-61
9. Resources
   1. DVT Prophylaxis Guidelines
      1. http://www.chestjournal.org/content/vol126/3_suppl/
10. References
    1. (2004) Chest 126:338-400
    2. Geerts (2001) Chest 119:132S-75S
    3. Hull (2001) Arch Intern Med 161:1952-60
    4. Ramzi (2004) Am Fam Physician 69:2841-8
    5. White (2000) N Engl J Med 343:1758-64