Deep Vein Thrombosis Prevention

See Also

Precautions
Venous Thromboembolism Risk Reduction

Early mobilization after surgery is critical
Perioperative risk of VTE varies by surgery, anesthesia
Decision to anticoagulate is individualized to patients
1. Does the risk of bleeding outweigh the VTE Risk
2. Most non-surgical patients do not require DVT Prophylaxis after discharge (unless VTE or other indication)
  1. Minimal benefit and associated with bleeding risk
  2. Spyropoulos (2018) N Engl J Med 379(12):1118-27 [PubMed]

Management
General

Anticoagulation start varies per medication and risk
Continue Anticoagulation for at least 10 days post-orthopedic surgery
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

Management
Perioperative protocol for the Highest Risk Patients

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
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
      1. Total knee arthroplasty or total hip arthroplasty (as alternative agent)
    2. However, Low Molecular Weight Heparin is much more effective
      1. 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)
      1. Some protocols use DOAC for the first 5 days, then Aspirin
    4. References
      1. (2012) Presc Lett 19(3): 16 [PubMed]
2. Additional strategies (with Anticoagulation)
  1. Intermittent Pneumatic Compression Stockings or
  2. Graduated Compression Stockings or
  3. Foot and calf pumping devices
Special circumstances: Prophylaxis after Total Knee Arthroplasty (TKA) or Total Hip Arthroplasty (THA)
1. Duration of DVT Prophylaxis (may be adjusted for mobility)
  1. Total Hip Arthroplasty: 10-14 days
  2. Total Knee Arthroplasty: 35 days
2. Low Molecular Weight Heparin (e.g. Enoxaparin or Lovenox)
  1. Gold standard Subcutaneous Injection therapy continued for 14 days after surgery (no monitoring needed)
3. Apixaban (Eliquis)
  1. Dose 2.5 mg orally twice daily for 14 days
  2. Compared with LMWH, Apixaban has equivalent efficacy in DVT Prophylaxis
4. Rivoroxaban (Xarelto)
  1. Dose: 10 mg orally once daily for 14 days (no monitoring needed)
  2. Compared with LMWH, prevents 4 more DVTs
  3. However is associated with 9 more serious bleeding events per 1000 patients
5. Warfarin
  1. Indicated in Creatinine Clearance <30 ml/min in which DOACs are contraindicated
  2. Variable dosing orally for 14 days (requires monitoring)
  3. Compared with LMWH, prevents 3 fewer DVTs
  4. However is associated with 2 more fatal bleeding events per 1000 patients
6. Aspirin
  1. Switch after 5 days on DOAC (e.g. Xarelto) and LMWH (e.g. Lovenox) to Aspirin
  2. Continue Aspirin 81 mg orally daily for at least 14 days, but preferably 35 days
  3. Consider in those without significant additional VTE Risks
    1. Do not use Aspirin prophylaxis in high risk patients (e.g. prior VTE, active cancer, immobile)
  4. References
    1. Anderson (2018) N Engl J Med 378(8):699-707 +PMID: 29466159
7. Dabigatran (Pradaxa)
  1. Not available in appropriate 220 mg dose for VTE prophylaxis in United States
8. References
  1. (2014) Presc Lett 21(6): 31-2
  2. (2018) Presc Lett 25(5): 25
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
Special circumstances: Elective hip surgery
1. Lose weight before surgery
2. Ambulation before the second post-surgical day
Special circumstances: Gynecologic Surgery
1. Unfractionated Heparin is the preferred agent

Management
Perioperative for High Risk Patients

Criteria
1. Patient with Thromboembolism risk and
  1. Age over 60 years and nonmajor surgery or
  2. Age over 40 years and major surgery
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

Management
Perioperative for Moderate Risk Patients

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
Management
1. Low Molecular Weight Heparin
  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

Management
Perioperative for Low Risk Patients

Criteria
1. Minor surgery in age <40 and no Thromboembolism risk
Management
1. No Anticoagulation
2. Early mobilization
3. Consider graduated Compression Stockings

Management
Other indications for prophylaxis

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
Long leg cast above knee (especially in elderly)
1. Kock (1995) 346:459-61 [PubMed]
Lower leg cast
1. Typically does not require DVT Prophylaxis in most cases
  1. van Adrichem (2017) N Engl J Med 376(6): 515-25 +PMID:27959702 [PubMed]
2. Exceptions in which DVT Prophylaxis is appropriate in lower leg Casting
  1. History of prior Venous Thromboembolism
  2. Achilles Tendon Rupture (controversial)
  3. Long distance air travel >6 hours planned
    1. Cesarone (2002) Angiology 53(1): 1-6 +PMID:11863301 [PubMed]
3. References
  1. Orman, DeLoughery and Ramadorai in Herbert (2017) EM:Rap 17(7): 13-4

Resources

DVT Prophylaxis Guidelines
1. http://www.chestjournal.org/content/vol126/3_suppl/

References