1. Management of Deep Vein Thrombos in Total Joint Arthroplasty
Total Hip and Knee Symposium
Los Cabos, Mexico

2. Frank R. Ebert, MD Assistant Chief Department of Orthopædics
The Union Memorial Hospital
Baltimore, Maryland

3. Number of Orthopedic Replacement Procedures/Year
Total knee replacements: 267,000/year in the US
Total hip replacements: more than ,000/year in the US
AAOS Website availiable at:

4. The Cost of DVT Risk persists for a long time following surgery.
90% of medical re-admissions following TJR are due to DVT; substantial direct inpatient costs related to DVT

5. Venous Thromboembolism: Pathogenesis
Venousthrombi
Usually form in regions of sluggish or altered flow in large venous sinuses
May break off, travel to lung – PE
Pathogenic factors
Activation of blood coagulation
Venous stasis
Vascular injury

6. Venous Thromboembolism: Natural History
Hip Procedures
Have a higher frequency of proximal clots
Knee Procedures
Deep calf veins
Usually asymptomatic
Thrombi tend to be small
Propagation is an issue

7. Venous Thromboembolism: Natural History (cont’d)
Proximal vein thrombi
Popliteal
Superficial femoral
Common femoral
Iliac veins
Spontaneous lysis of large thrombi uncommon
Strong association between DVT and PE

8. Venous Thromboembolism: Diagnosis
Clinical Exam 50/50
Venous duplex ultrasound
Venography

9. Venous Thromboembolism: Diagnosis (cont’d)
Venous duplex ultrasound
Noninvasive
Assesses vein compressibility
Very sensitive in proximal thrombi
Less sensitive in distal

10. Venous Thromboembolism: Diagnosis (cont’d)
Venography
FDA standard for DVT
Clinically outmoded

11. Pulmonary Embolism: Diagnosis
Screening
V/Q scan
Effective non-invasive technique
Probability of PE based on degree of mismatch between ventilation and perfusion

12. Pulmonary Embolism: Diagnosis (cont’d)
Definitive test
Pulmonary angiogram
Spiral CT

13. Venous Thromboembolism: Prognosis
Proximal DVT: postoperative, good, if treated for 3 months with anticoagulant therapy
Recurrent events: 5%
After discontinuation of anticoagulant therapy:
5% to 10% after 1 year
Approximately 30% after 8 years
Hirsh J, Hoak J. Circulation. 1996;93:2213.

14. Clinical Risk Factors for DVT
Major surgery (eg, total joint arthroplasty)
History of DVT
Age ≥40
Obesity
Prolonged immobility
Genetic predisposition to hematologic abnormalities
Trauma
Other: malignancy, coronary syndromes (eg, unstable angina)
Anderson FA Jr, Wheeler HB. Clin Chest Med. 1995;16:236.

15. Hip Fracture, Hip Arthroplasty, Knee Arthroplasty, and VTE Risk (Upper Limits) in Patients without Anticoagulative Prophylaxis
100 90
Hip arthroplasty
84% 80
Knee arthroplasty 70
60%
Hip fracture surgery 60
57%
% of patients*† 50 40
36%
36% 30
20% 20
12.9% 10
0.7%
0.4%
All DVT
Proximal DVT
Fatal PE
* DVT prevalence statistics obtained by use of mandatory postoperative venography.
† Represents the upper limit of prevalence statistics for each procedure.
Geerts WH, et al. Chest. 2001;119(suppl):140S.

16. Patients Not Receiving Anticoagulation Prophylaxis: Summary
Orthopedic surgery creates the ideal conditions for the development of DVT
Vascular damage
Venous stasis
Hypercoagulability
≥50% of patients undergoing orthopedic surgery will develop DVT
Most frequently utilized agents all demonstrate superiority compared with placebo

17. Current Strategies for DVT Prophylaxis
Mechanical prophylaxis
Pharmacologic anticoagulant therapy
Combination therapy
Regional anesthesia

18. Current Strategies: Mechanical Prophylaxis
Intermittent pneumatic compression (IPC)
Pneumatic plantar compression (foot pump)
Literature supports use – Sarmiento JBJS 1999
Ineffective when BMI > 25 kg/m2

19. Current Strategies: Mechanical Prophylaxis (cont’d)
Advantages
Local antistasis effects
Systemic humeral effects
No increase in bleeding risk
Disadvantages
Patient intolerance
Compliance difficulties
Impractical post-hospital discharge application
Less effective when BMI >25

20. Current Strategies: Anticoagulant Therapy and Indications
Oral agents
Warfarin (dose-adjusted to INR 2.0–3.0)
Prophylaxis of venous thrombosis and its extension, and pulmonary embolism
Aspirin
May be effective when combined with mechanical agents – Sarmiento JBJS 1999

21. Current Strategies: Anticoagulant Therapy and Indications
Injectable/parenteral
Dose-adjusted unfractionated heparin (UFH)
Prophylaxis of venous thrombosis and its extension
Low-molecular-weight heparins (LMWH)
Dalteparin: total hip replacement
Enoxaparin: total hip replacement, total knee replacement

22. Current Strategies: Oral Anticoagulant Therapy
Warfarin
Reduces DVT and symptomatic PE rate
Lieberman, et al. JBJS 1997
In combination with mechanical agents, has a reduction in total DVT rate
Freedman, et al. JBJS 2000

23. Current Strategies: Oral Anticoagulant Therapy
LMWHs
Fractionated Heparin 1/3 molecular weight of standard Heparin – inhibits Clotting Factor 10
Binds less to plasma protein, increases bioavailability of the LMWHs

24. Current Strategies: Oral Anticoagulant Therapy
LMWHs
Enoxaparin
Dosage - 30mg SC twice daily
Treatment begun within 24hrs after THA
Significant lowering DVT/PE rate comparable to Warfarin
Colwell, et al. JBJS 1994

25. Current Strategies: Oral Anticoagulant Therapy
LMWHs
Enoxaparin
In TKA may be superior to Warfarin in reducing DVT rate.
Heit, et al. Thromb Haemost. 1997

26. Current Strategies: Oral Anticoagulant Therapy
LMWHs
Dalteparin
Dosage – 2500 IU SC 4hrs post surgery followed by 5000 IU SC daily
Dalteparin proved effective in the reduction of total DVT and symptomatic PE when compared to Heparin
Hull, et al. Arch Intern Med. 2000

27. ANTI-COAGULANT THERAPY LMWH’s
Organon-Highly selective inhibitor for factor X
FDA approved for Hip Fracture, THA, TKA

28. Current Strategies: Parenteral Anticoagulant Therapy
Advantages
Rapid onset
No monitoring (LMWH)
Superior efficacy (LMWH)
Disadvantages
LMWH
SQ route
Bleeding risks
Must initiate at least 12 hrs post surgery
Contraindicated in regional anesthesia - FDA
Hirsh J, Hoak J. Circulation. 1996;93:

29. Current Strategies: Anticoagulant Therapy
Duration of Prophylactic Treatment
Clinical trials supports usage of prophylaxis
Period of hospitalization – 4-15 days
Post-hospitalization – (meta-analysis review) days
Hull, et al. Ann Intern Med. 2001

30. Current Strategies: Anticoagulant Therapy
Indications for Greenfield Filter Placement
Recurrent history of pulmonary emboli
Unable to use anticoagulant therapy in the presence of a DVT
Presence of pulmonary emboli despite anticoagulation therapy

31. ACCP 2001 Recommendations: Based on 7 to 10 Days’ Treatment
Hip Knee Hip Replacement Replacement Fracture
Stockings Adjuvant – –
Intermittent Adjuvant Yes Adjuvant pneumatic Grade 2C Grade 1B compression
Aspirin – – –
Adjusted-dose Yes unfractionated Grade 2A – – heparin
Warfarin Yes Yes Yes INR 2-3 INR 2-3 INR Grade 1A Grade 1A Grade 1B
LMWH Yes Yes Yes Grade 1A Grade 1A Grade 1B
Geerts WH, et al. Chest. 2001;119(suppl):157S.

32. SUMMARY
Treatment of DVT is required following THA, TKA,and Hip Fracture
Aspirin has literature support clearly for THA
Warfarin and LMWH clearly show effectivenss for THA,TKA,and Hip Fracture
Post discharge usage should be for up to 35 days post op

33. Summary TJA places patients at risk for VTE
Thromboprophylaxis: the standard of care following TJA due to high rates of VTE without prophylaxis
Significant variation in prescribing practices
There are no data for efficacy of combined mechanical/pharmacologic treatments
Novel thromboprophylactic agents potentially may improve risk/benefit ratio

34. THANK-YOU