Thrombosis 1
Objectives:
- Identify the differences between a thrombus and an embolus
- describe the major anatomic sites of venous thrombosis
- describe the role of endothelial cells neutrophils and monocytes in the initiation of venous thrombosis
- describe the major risk factors for venous thrombosis
- describe the investigation (blood tests, imaging) for venous thrombosis
- describe the origina and consequences of pulmonary embolism
- list the anticoagulants that are used in venous thrombosis
- describe clinically important complications after venous thrombosis
Thrombus vs embolism
embolus is free floating and can travel. often is made up of thrombus
thrombus is coagulated blood.
venous vs arterial thrombosis
venous stasis mediated (usually) fibrin and cells
arterial occurs in atherosclerotic arteries initiated by damaged endothelium platelet mediated
Factors for DVT
- trauma
- leg surgey
- immobility
- nursing home
- obesity
- pregnancy
- age
cellular basis of DVT
Stasis in calf veins during surgey or immobility endothelium becomes hypoxic nd activated neutrophils and monocytes adhere to vessel wall because of selectin expression neutrophils adhere and undergo NETosis DNA activates FXII activating coagulation cascade
monocytes adhere to selectins express tissue factor and activate the extrinsic pathway
Presentation
DVT
LEg swelling -unilateral pain warmth skin discolouratoin
suddenly over weeks and days
Pulmonary embolism
shortness of breath chestpain nonproductive cough haemptysis
Risk factors for VTE
Diagnosis of DVT The Wells score plus D-DImer
followed if appropriate by compression ultrasounds imaging studies
PE diagnosis
CT pulmonary angiography
Acute treatment of VTE
Direct oral anticoagulant Low Molecule Weight Heparin Warfarin Thrombolysis
provoked vs unprovokes thromboses Identifiable event at fault vs spontaneous
consequences of Venous thrombosis
Acute
- Pulmonary embolism
- local oedema
chronic
- raised venous ressure
- varicose veins
- chronic ulcers
- swelling
- chronic pain