Zusammenfassung der Ressource
Virchow'sTriad
- ENDOTHELIAL INJURY
- Exposure of subEN ECM
- Platelet adhesion
- Release of Tissue factor
- NB cause of arterial thrombus formarion
- d/t MI, atherosclerosis leading to
ulcerated plaques, vasculitis
- Prothrombotic
- Hypertension
- Bacterial endotoxins
- Hypercholesterolaemia
- Radiation
- Cigarette smoking
- Mural thrombi – in chambers of heart
d/t abnormal contraction
- Rheumatic heart dx > mitral valve stenosis
> LA dilation > atrial fibrilation
- In aorta d/t anuerism, ruptured atherosclerotic
plaque, often occludes
- BLOOD HYPERCOAGULABILITY
- Primary – inherited
- Secondary – aquired
- High risk
- Prolonged immobilisation/bed rest
- Atrial fibrilation
- Tissue damage – surgery, fracture, burns
- Disseminated cancer – release coagulation factors
- Low risk
- Cardiomyopathy
- Nephrotic syndrome
- Hyper-oestrogenic states – OCP,pregnancy, HRT
- Sickle cell anaemia
- Smoking (+ EN damage so double risk)
- ↑ age > ↑ platelet aggregation > ↓ prostacyclin
- BLOOD STASIS/TURBULENCE
- Turbulence
- Atherosclerosis – counter currents and pockets of stasis
- EN damage/dysfuntion
- Stasis
- NB cause of venous thrombus formation
- Usually occlusive, mostly DVT > oedema + distal swelling
- Superficial Saphenous system > visible swelling/pain > rarely embolises
- Deep thrombi above knee (popliteal/femoral/illiac)
>usually asymptomatic > can embolise
- d/t CCF, ↑ age, immobilisation, obesity,
post-surgery, migratory thrombophlebitis
- Pockets of stasis behid obstruction, cause further enlargement
- Laminar flow disrupted
- Platelets come into contact with EN
- ↓ dilution of coagulation factors, ↓ inflow of clotting inhibitors
- ↑ EN activation > leukocyte edhesion > thrombus formation
- PT
- Extrinsic pathway, 11-13 sec
- Add Ca+ to form quick fibrin clot
- Sensitive to Coumadin
- Prothrombin Time
- PTT
- Partial Thromboplastin Time
- Add Ca+ and surface phospholipids
- Intrinsic pathway, 28-35 sec
- Sensitive to Heparin