Australian Orthopaedic Nurses’ Association 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) Annual risk in developed countries

What is VTE? Annual risk in developed countries

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 Annual risk in developed countries 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 Medicine 2002, 8:365–371

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.

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

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 TRENDS!!!!! Not exact numbers – watch for gradients 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 Venography gold standard but invasive Tovey C et al. Diagnosis, investigation, and management of deep vein thrombosis. BMJ 2003;326;1180-1184

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;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 CTPA Probability CTPA Diagnostic Contrast

Treatment Anticoagulation IVC filter Compression stockings 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!

Questions?

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 Medicine 2002, 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 Medicine 2002, 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 Medicine 2002, 8:365–371