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VTE in Orthopaedics . Australian Orthopaedic Nurses’ Association 15 May 2009 Dr Lachlan Milne. What is VTE?. Venous thromboembolism (VTE) Deep Vein Thrombosis (DVT) Pulmonary Embolism (PE). What is VTE?. Why is VTE a problem?. VTE annual risk 1-2 per 1000 people 1
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VTE in Orthopaedics Australian Orthopaedic Nurses’ Association 15 May 2009 Dr Lachlan Milne
What is VTE? • Venous thromboembolism (VTE) • Deep Vein Thrombosis (DVT) • Pulmonary Embolism (PE)
Why is VTE a problem? • VTE annual risk 1-2 per 1000 people1 • 40 000 per year in Australia • PE: 0.2% deaths per year in Australia2 • Morbidity higher than mortality • Ho et al. Venous thromboembolism: diagnosis and management of deep venous thrombosis MJA 2005; 182 (9): 476-481 • Australian Bureau of Statistics 2006
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;1180-1184
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 Medicine2002, 8:365–371
DVT Pathophysiology • Virchow’s Triad • Endothelial injury • Surgery • Venous stasis • Tourniquet • Immobilisation • Delayed ambulation • Casting • Change in blood constituents • ↑ platelets • ↑ clotting • ↑ viscosity • Virchow RLK (1856). Thrombosis und Embolie. Gefässentzündung und septische Infektion". Gesammelte Abhandlungen zur wissenschaftlichen Medicin. pp. 219–732.
Risk factors • Increased in orthopaedics: • Immobilisation • Major surgery • Tourniquet • Other non orthopaedic • Obesity BMI >30 (often in arthroplasties) • History of prior DVT • Female • Smoking • OCP • Genetic (many) • White et al: Risk factors for venous thromboembolism after total hip and knee replacement surgery. Current Opinion in Pulmonary Medicine2002, 8:365–371
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): 476-481
VTE – Signs and Symptoms • DVT1 • Leg swelling/erythema • Leg pain • Superficial venous congestion • PE • Symptoms: • Dyspnoea • Pleuritic chest pain • Signs: • ↑ PR • ↓ SaO2 • ↑ RR • Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184
Diagnosis of DVT1 • Unreliable • Clinical assessment algorithm • Screening investigations • Definitive investigations • Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184
Clinical assessment algorithm1 • 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;1180-1184
Screening Investigations • D Dimer assay • Degradation product of fibrin • Elevated in 80% of VTE • Fast • Low specificity • Useless in context of surgery
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;1180-1184
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: 541-86.
Definitive Investigations • CT venography • Highly sensitive and specific • Huge amount of radiation • Not much improvement on US • Rarely used
Definitive Investigations • MRI • Best invasiveness to sensitivity ratio • Expensive • Unlikely to be used frequently until costs decrease
Diagnosis of PE • Clinical judgement • Arterial Blood Gas • VQ scan • Probability • CTPA • Diagnostic • Contrast
Treatment • Anticoagulation • Heparin • Unfractionated • Low Molecular Weight • Warfarin • IVC filter • Compression stockings
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
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
Treatment – IVC filter • When anticoagulation contraindicated • eg orthopaedic patients undergoing surgery • Recurrent DVT despite adequate anticoagulation
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
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
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
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
What YOU can do… • Daily check on your patients: • Stockings or compressors • Heparin or Clexane or Warfarin • Remind medical staff
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
What YOU can do… • Pre-discharge check – according to protocol • Stockings • Clexane • Doppler Ultrasound • YOU can make a difference!
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): 476-481 • 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: 541-86. • Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184 • 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 Medicine2002, 8:365–371
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): 476-481 • 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: 541-86. • Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184 • 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 Medicine2002, 8:365–371
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): 476-481 • 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: 541-86. • Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184 • 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 Medicine2002, 8:365–371