1. Deep vein thrombosis and pulmonary embolism.

2. Homeostasis
Vessel wall.
Platelets.
Circulating coagulation protein.

3. Thrombosis. Virchows triad. 1- blood flow.
2- surface in contact with blood.
3- clotting components.

4. Blood flow. Atrial fibrillation. Left ventricular dysfunction.
Immobility.
Vessel obstruction.
Hyperviscosity.
Sickle cell anemia.

5. Abnormalities of surfaces in contact with blood
Vessel injury – trauma.
Atherosclerosis.
Heart valve disease – or replacement.
Indwelling catheter.

6. Abnormalities of circulating coagulation proteins.
Protein C and protein S deficiency.
Activated protein C resistance.
Antithrombin 111 deficiency.
Antiphospholipid antibodies.
Hyperhomocysteinemia.
Malignancy.
High dose estrogen therapy / pregnancy increased fibrinogen level?.

7. Risk factors for thrombosis.
Age > 40 years.
Immobility.
Previous DVT / PE or thromboembolic event.
Surgery.
Major trauma.
Pregnancy / postpartum / high dose estrogen therapy.
Occult and diagnosed malignancy.
Inherited or acquired alteration in circulating proteins.
Polycythemia.
Sever heart failure.
Diabetes. ?

8. Signs and symptoms. Symptoms often absent. Symptoms non specific.
Symptoms due to inflammation and obstruction of venous flow.
Deep vein thrombosis : unilateral calf swelling, calf pain and tenderness, calf erythema, dilatation of superficial vein, palpable cord,
Pulmonary embolism: dyspnea , chest pain, tachycardia, hypotension, cyanosis, hemoptysis.

9. Diagnostic testing – DVT.
Venography.
Ultrasononagraphy – Doppler.
Impedance plethysmography.
Fibrinogen leg scanning.

10. Diagnostic testing – PE.
Pulmonary angiography.
Ventilation perfusion scan.
Spiral CT scan.
D – dimer.

11. Hypercoagulable work – up.
Protein C deficiency.
Protein S deficiency.
Anti – Thrombin 111 deficiency.
Activated protein C Resistance. ( factor V Lieden ).
Antiphospholipid Antibodies / anticardiolipin / lupus anticoagulant.