1. Australian Orthopaedic Nurses’ Association
VTE in Orthopaedics
Australian Orthopaedic Nurses’ Association
15 May 2009
Dr Lachlan Milne

2. What is VTE? Venous thromboembolism (VTE) Deep Vein Thrombosis (DVT)
Pulmonary Embolism (PE)
Annual risk in developed countries

3. What is VTE?
Annual risk in developed countries

4. Why is VTE a problem? VTE annual risk 1-2 per 1000 people1
per year in Australia
PE: 0.2% deaths per year in Australia2
Morbidity higher than mortality
Annual risk in developed countries
Ho et al. Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9):
Australian Bureau of Statistics 2006

5. Consequences of DVT Death Pulmonary Embolism
Post-thrombotic Syndrome (chronic V HT)
Venous stasis
Leg pain and swelling
Hyperpigmentation
Leg ulcers
Recurrent Venous Thromboembolism
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;

6. DVT in orthopaedics?
Orthopaedic patients are most at risk of all patients in hospital1
Total Joint Arthroplasties
Major Trauma
Hip Fractures
White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine 2002, 8:365–371

7. DVT Pathophysiology Virchow’s Triad Endothelial injury Venous stasis
Surgery
Venous stasis
Tourniquet
Immobilisation
Delayed ambulation
Casting
Change in blood constituents
↑ platelets
↑ clotting
↑ viscosity
Virchow, in 1856, elucidated the pathophysiology of PE and defined the above three factors as the cause of DVT and thus PE. They became known as Virchow’s Triad.
Virchow RLK (1856). Thrombosis und Embolie. Gefässentzündung und septische Infektion". Gesammelte Abhandlungen zur wissenschaftlichen Medicin. pp. 219–732.

8. Risk factors Increased in orthopaedics: Other non orthopaedic
Immobilisation
Major surgery
Tourniquet
Other non orthopaedic
Obesity BMI >30 (often in arthroplasties)
History of prior DVT
Female
Smoking
OCP
Genetic (many)
Risk factors - Why are we susceptible to them?
White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine 2002, 8:365–371

9. Course of DVT illness Determined by the site of thrombosis1 Calf
Where DVTs start
50% resolve in 3/7
Rarely causes PE in isolation
25% extend proximally within 1 week
Proximal
Symptomatic
50% have PE at Dx
only 1 in 5 of those is symptomatic of PE
Ho W. et al Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9):

10. VTE – Signs and Symptoms
DVT1
Leg swelling/erythema
Leg pain
Superficial venous congestion PE
Symptoms:
Dyspnoea
Pleuritic chest pain
Signs:
↑ PR
↓ SaO2
↑ RR
TRENDS!!!!! Not exact numbers – watch for gradients
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;

11. Diagnosis of DVT1 Unreliable Clinical assessment algorithm
Screening investigations
Definitive investigations
Venography gold standard but invasive
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;

12. Clinical assessment algorithm1
Clinical feature
Score
Active cancer <6/12 ago 1
Recent immobilisation of legs
Recently bedridden >3/7 AND/OR
Major surgery <4/52
Tender over deep venous system
Entire leg swollen
Calf swelling >3cm
Collateral superficial non varicose veins
Pitting oedema > asymptomatic
Alternative diagnosis likely -2
Low prob ≤0
Mod prob 1-2
High prob ≥3
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;

13. Screening Investigations
D Dimer assay
Degradation product of fibrin
Elevated in 80% of VTE
Fast
Low specificity
Useless in context of surgery

14. Definitive Ix – Venography1
Gold standard
Invasive
Painful
Risks:
Thrombosis
Contrast allergy
Venogram showing popliteal vein thrombosis
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;

15. Definitive Ix - Ultrasound
Non invasive
Safe
Good Sensitivity
97% proximal
75% calf1
Compression US
Doppler
Kraaijenhagen RA et al. Diagnostic management of venous thromboembolism. Baillières Clin Haematol 1998;11:

19. Definitive Investigations
CT venography
Highly sensitive and specific
Huge amount of radiation
Not much improvement on US
Rarely used

21. Definitive Investigations
MRI
Best invasiveness to sensitivity ratio
Expensive
Unlikely to be used frequently until costs decrease

22. Diagnosis of PE Clinical judgement Arterial Blood Gas VQ scan CTPA
Probability
CTPA
Diagnostic
Contrast

25. Treatment Anticoagulation IVC filter Compression stockings Heparin
Unfractionated
Low Molecular Weight
Warfarin
IVC filter
Compression stockings

26. Treatment - Heparin Minimum 5/7 until warfarin therapeutic
Unfractionated
Infusion
Q6h monitoring
Renal impairment
Low Molecular Weight Heparin
consistent response
Longer t ½ – Daily dosing
Effective
↓ haemorrhage
Nephrotoxic

27. Treatment - Warfarin Oral dosing Prothrombotic initially
Heparin/Clexane
Monitoring with INR target 2.0 – 3.0
Not used in pregnancy – crosses placenta
6/12 treatment

28. Treatment – IVC filter When anticoagulation contraindicated
eg orthopaedic patients undergoing surgery
Recurrent DVT despite adequate anticoagulation

29. Treatment – Stockings Simple and cost effective
Reduce likelihood of post-thrombotic syndrome
Wear for 18 months post DVT 1
Brandjes DP et al. Randomised trial of effect of compression stockings in patients with symptomatic proximal-vein thrombosis. Lancet 1997;349:759-62

30. Prevention Orthopaedic patients most at risk
Australian Therapeutic Guidelines
Medical
Mechanical
Geerts WH et al. Prevention of Venous Thromboembolism The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy

31. Prevention – Mechanical
Should be commenced evening prior to surgery
Stockings:
GCS – Graduated Compression Stockings
TEDs – ThromboEmbolic Deterrents
Compressors:
SCDs – Sequential Compression Devices
IPC – Intermittent Pneumatic Compression

32. Prevention - Medical Should be commenced within 24 hours after surgery
LMWH enoxaparin/Clexane 40mg SC D
Reduce to 20mg if Cr Cl < 30mL/min
Heparin 5000u SC BD
Continue 5-10 days unless Hip Arthroplasty/Fracture 28 – 35 days
Aspirin NOT considered adequate alone

33. What YOU can do… Daily check on your patients:
Stockings or compressors
Heparin or Clexane or Warfarin
Remind medical staff

34. What YOU can do… Respond to patients who complain of
dyspnoea
pleuritic chest pain
calf pain
unexplained unilateral leg swelling
Respond to changes in your patient’s obs
↓SaO2
↑ PR
↑ RR
Take responsibility and make the team aware

35. What YOU can do… Pre-discharge check – according to protocol
Stockings
Clexane
Doppler Ultrasound
YOU can make a difference!

36. Questions?

37. References
Brandjes DP et al. Randomised trial of effect of compression stockings in patients with symptomatic proximal-vein thrombosis. Lancet 1997;349:759-62
Geerts WH et al. Prevention of Venous Thromboembolism The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy
Ho et al. Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9):
Australian Bureau of Statistics 2006
Kraaijenhagen RA, Lensing AW, Wallis JW, van Beek EJ, ten Cate JW, Buller HR. Diagnostic management of venous thromboembolism. Baillières Clin Haematol 1998;11:
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;
Virchow RLK (1856). Thrombosis und Embolie. Gefässentzündung und septische Infektion". Gesammelte Abhandlungen zur wissenschaftlichen Medicin. pp. 219–732.
White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine 2002, 8:365–371

38. References
Brandjes DP et al. Randomised trial of effect of compression stockings in patients with symptomatic proximal-vein thrombosis. Lancet 1997;349:759-62
Geerts WH et al. Prevention of Venous Thromboembolism The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy
Ho et al. Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9):
Australian Bureau of Statistics 2006
Kraaijenhagen RA, Lensing AW, Wallis JW, van Beek EJ, ten Cate JW, Buller HR. Diagnostic management of venous thromboembolism. Baillières Clin Haematol 1998;11:
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;
Virchow RLK (1856). Thrombosis und Embolie. Gefässentzündung und septische Infektion". Gesammelte Abhandlungen zur wissenschaftlichen Medicin. pp. 219–732.
White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine 2002, 8:365–371

39. References
Brandjes DP et al. Randomised trial of effect of compression stockings in patients with symptomatic proximal-vein thrombosis. Lancet 1997;349:759-62
Geerts WH et al. Prevention of Venous Thromboembolism The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy
Ho et al. Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9):
Australian Bureau of Statistics 2006
Kraaijenhagen RA, Lensing AW, Wallis JW, van Beek EJ, ten Cate JW, Buller HR. Diagnostic management of venous thromboembolism. Baillières Clin Haematol 1998;11:
Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;
Virchow RLK (1856). Thrombosis und Embolie. Gefässentzündung und septische Infektion". Gesammelte Abhandlungen zur wissenschaftlichen Medicin. pp. 219–732.
White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine 2002, 8:365–371