dvt.

Deep vein thrombosis : 

Deep vein thrombosis Dr.P.Savithiri CMC,Vellore.

Objectives : 

Objectives Definition Prevalence Pathophysiology Causes Signs and symptoms Prophylaxsis Management Recent approach

Deep Vein Thrombosis : 

Deep Vein Thrombosis

Deep Vein Thrombosis : 

Deep Vein Thrombosis 80 % proximal thrombosis 20% calf vein thrombosis 50% progress to PE

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Cancer Estrogen use Family history IBD Nephrotic syndrome Blood transfusions Thrombophilia Surgery Prior DVT Central venous access Cancer chemotherapy or radiotherapy Age >40 years Immobilization MI CHF Paralysis

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Patient Group DVT Prevalence % Medical patients 10–20 General surgery 15–40 Major gynecologic surgery 15–40 Major urologic surgery 15–40 Neurosurgery 15–40 Stroke 20–50 Hip or knee arthroplasty, hip fracture surgery 40–60 Major trauma 40–80 Spinal cord injury 60–80 Critical care patients 10–80 Geerts et al.Chest, 2004;126:338S

Signs and symptoms : 

Signs and symptoms Discoloration of the legs Calf or leg pain or tenderness Swelling of the leg or lower limb Warm skin Surface veins become more visible Leg fatigue

Sequelae of DVT : 

Sequelae of DVT

Importance of DVT diagnosis : 

Importance of DVT diagnosis If left untreated, can suffer fatal PE Treatment of proximal DVT reduces the risk of fatal PE to <1% and the risk of developing recurrent DVTs to 5%

Diagnosis : 

Diagnosis History Clinical examination Pre test probability Screening Investigation Treatment

Homan’s Sign : 

Homan’s Sign Forcible ankle dorsiflexion with the knee flexed causing deep calf pain

Wells criteria : 

Wells criteria Malignancy (Rxn < 6 mos or palliative) +1 Lower limb paralysis/ recent plaster cast +1 Bedridden for > 3 days/ surgery (< 4 weeks) +1 Localized tenderness along deep veins +1 Entire leg swollen +1 Calf swelling > 3 cm asymptotic side +1 Pitting edema confined to symptomatic leg +1 Dilated superficial veins (non-varicose) +1 Alternative diagnosis > or = that of DVT -2

Wells criteria : 

Wells criteria > 3: High -75% 1-2 :Moderate -17% < 0 :Low -3%

Investigation : 

Investigation Screening test Definitive investigation

Screening test : 

Screening test D-dimer test: Degradation product of a cross-linked fibrin blood clot Increased in: Arterial and venous thrombosis Major surgery Hemorrhage Trauma Pregnancy cancer

Plethysmography : 

Plethysmography Digital photoplethysmography Strain gauge plethysmography Impedance plethysmography

Digital plethysmography : 

Digital plethysmography

Plethysmograph : 

Plethysmograph

Definitive investigation : 

Definitive investigation Venography : Gold standard Ultrasonography:  Compression ultrasound Duplex ultrasonography Colour coded Doppler ultrasonography Computed tomography Magnetic resonance imaging

venography : 

venography

Management : 

Management Medical management Surgical management

Medical management : 

Medical management Compressional stockings Heparin Warfarin Vitamin k antagonist

Compression stockings : 

Compression stockings Apply a certain amount of pressure near your ankle and then apply gradually less and less pressure as they move up the leg They help to squeeze or push blood back up the leg from the ankle to the thigh in an effort to counteract pooling of blood in the leg and the resultant swelling.

Mechanisms of Elastic Compression Stockings : 

Mechanisms of Elastic Compression Stockings ↓ Venous dilatation ↑ Flow velocity Improve valve function ↑ Tissue Factor Pathway Inhibitor

Initial Treatment of DVT : 

Initial Treatment of DVT Initial TX (LMWH/UFH) at least 5 days DC heparin once INR stable and > 2.0 Massive ileofemoral DVT: IV thrombolysis , venous thrombectomy ACCP2004;

Heparin : 

Heparin Unfractionised heparin Low molecular weight heparin Fondaparinux They inhibit factor Xa . Inhibits Factor IX & potentiates the action of antithrombin III – Intrinsic Clotting Pathway Inhibits thrombin-mediated conversion of fibrinogen to fibrin

LMWH : Advantage Over UFH : 

LMWH : Advantage Over UFH Increased binding to plasma proteins or endothelium in turn leading to a.  Increased bioavailability b. Predictable anticoagulant response. Affinity for macrophages resulting in increase half life. Affinity for platelets and platelet factor 4 binding to osteoblasts

LMWH : Advantage Over UFH : 

LMWH : Advantage Over UFH No monitoring required No hospitalization required Convenient O.D. doses Decreased incidence of thrombocytopenia Osteopenia

Fondaparinux : 

Fondaparinux A good alternative to heparins selective antithrombin-mediated inhibition of factor Xa To be used with caution in patients with renal insufficiency It is eliminated via the kidneys Its half-life is considerably longer than those of the low-molecular-weight heparins.

Newer drug : 

Newer drug Edoxaban is a new oral direct factor Xa inhibitor. The purpose of this study was to evaluate the efficacy and safety of different doses of edoxaban for the prevention of venous thromboembolism (VTE) in patients undergoing elective total hip replacement Thromb Haemost. 2010 Jun 29;104. [Epub ahead of print] Oral direct factor Xa inhibition with edoxaban for thromboprophylaxis after elective total hip replacement. A randomised double-blind dose-response study.

A dose-ranging study evaluating the oral factor Xa inhibitor edoxaban for the prevention of venous thromboembolism in patients undergoing total knee arthroplasty. : 

A dose-ranging study evaluating the oral factor Xa inhibitor edoxaban for the prevention of venous thromboembolism in patients undergoing total knee arthroplasty. Edoxaban demonstrated significant dose-dependent reductions in VTE in patients undergoing TKA with a bleeding incidence similar to placebo J Thromb Haemost. 2010 Aug 12. [Epub ahead of print]

COUMADIN : 

COUMADIN Start once acute anticoagulation achieved Start with 5mg PO qday OR 10mg PO q day If start with 10mg then achieve therapeutic INR 1.4 days sooner Complications and morbidity no different in 5mg or 10mg start Goal INR 2 to 3

Duration of Anticoagulation for DVT : 

Duration of Anticoagulation for DVT *From American College of Chest Physicians

Prophylaxsis : 

Prophylaxsis Risk group Recommended prophylaxis Hip replacement Warfarin, LMWH, fondaparinux Knee replacement Warfarin, LMWH, IPC, fondaparinux (Arixtra) Hip Fracture Warfarin, LMWH, fondaparinux Major trauma LMWH, IPC Abdominal surgery UFH, LMWH, IPC, warfarin, ES Medical Patients UFH, LMWH, ES IPC-Intermittent Pneumatic Compression ES-Elastic stocking

Effective prophylaxis : 

Effective prophylaxis Subcutaneous heparin-5000IU Q8H for 5 days Aspirin 150mg started preoperatively and continued till 45 days Graduated elastic compression stockings Intermittent pneumatic compression Mechanical foot pumps

Surgical management : 

Surgical management IVC filter Embolectomy Thrombolysis

IVC filter : 

IVC filter The filter is inserted inside a large vein The filter catches blood clots that break off in a vein before they move to the lungs This prevents pulmonary embolism. However, it doesn't stop new blood clots from forming.

Greenfield stainless steel filter : 

Greenfield stainless steel filter

Indication : 

Indication Pulmonary embolism with contraindication to anticoagulation   Recurrent pulmonary embolism despite adequate anticoagulation.

Slide 42: 

AngioJet Trellis Ekos

Embolectomy : 

Embolectomy Indication: In those where thrombolysis is contraindicated or fails

Mechanical embolectomy : 

Mechanical embolectomy AngioJet

Thrombolysis : 

Thrombolysis Considered once P.E. diagnosed If chosen, hold anticoagulation during thrombolysis infusion, then resumed Associated with higher incidence of major hemorrhage

Thrombolysis-indication : 

Thrombolysis-indication Persistent hypotension Severe hypoxemia Large perfusion defecs, Right ventricular dysfunction Free floating right ventricular thrombus Paten foramen ovale Activase or streptokinase

Tips to prevent DVT : 

Tips to prevent DVT Exercising the legs regularly -- take a brisk walk every day Maintaining a reasonable body weight Avoiding sitting or lying in bed for long periods of time Avoiding tight-fitting, restrictive clothing Sitting with both legs on the floor (uncrossed)

Anticoagulation for the initial treatment of venous thromboembolism in patients with cancer. : 

Anticoagulation for the initial treatment of venous thromboembolism in patients with cancer. Based on the included trials, LMWH is likely to be superior to UFH in the initial treatment of VTE in patients with cancer. However, there is a need for more trials to better address this research question in cancer patients. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD006649.

References : 

References American College of Chest Physicians DVT & PE Risks, Symptoms, Diagnosis, Prevention, & Treatment Stuart T. Haines, Pharm.D., BCPS March 2004 Lin et al, Am J Surg, 2006 Geerts et al; Chest 2001, 2004

Thank you : 

Thank you