P4 - Fluids and Vascular Disorders Part 2 Flashcards
primary hemostasis goal
- platelet plug formation
components of primary hemostasis (3)
- platelet adhesion to vWF
- platelet dense granule release (ADP)
- platelet aggregation
components of secondary hemostasis (4)
- tissue factor released
- activates local coagulation factors
- convert prothrombin to thrombin
- fibrin forms around platelets fibrin/platelet aggregate
pathways of coagulation (3)
- extrinsic
- intrinsic
- common
antithrombotic factors (5)
- anti-thrombin III
- TFPI
- Protein C/S vit K dependent inhibitors of Va and VIIIa
- endothelial products inhibit platelets
- tPA
role of anti-thrombin III
- binds heparin-like molecules on enothelium and platelets, inhibits IIa, Xa, and IXa localized to active site
role of TFPI
- inactivates TF-VIIa complexes
role of protein C/S vit K dependent inhibitors of Va and VIIIa
- IIa activates protein C
- Protein S is a cofactor for protein C
tPA activates
- fibrinolysis
hemorrhage due to abnormal function or integrity of (3)
- blood vessels
- platelets
- coagulation factors
types of hemorrhage (3)
- petechial
- ecchymosis
- suffusive
petechial hemorrhage
- due to diapedesis
- < 3mm
ecchymosis hemorrhage
- damage to capillary beds
- > 1 cm
suffusive hemorrhage
- hemorrhage of large areas
factor X deficiency clinical signs
- severe bleeding
factor XI deficiency clinical signs
- bleed can be severe after surgery
factor IX (hemophilia B) deficiency clinical signs
- variable severity
- can be severe in large dogs
factor VIII (hemophilia A) deficiency clinical signs
- mild to severe
- mucosal hemorrhage
- post surgical bleeding
vit K dependent deficiency clinical signs
- moderate to severe
- sometimes fatal
vWF deficiency clinical signs
- mucosal bleeding can be severe in large dogs and horses
- primary hemostasis
- mildly affected animals do not spontaneously bleed
thromboembolus
- persistent or abnormal thrombosis and form in lumen of vessels, blood or lymph
mural thrombus
- thrombosis that forms inside of heart
thrombus formation due to (3)
- abnormal blood flow
- hypercoagulability
- endothelial injury and activation
artery thrombi features
- pale or white
venous thrombi features
- red
post mortem thrombi
- softer and no vascular attachment
small thrombi removal by
- thrombolysis
large thrombi removal by
- phagocytes with subsequent granulation tissue
common pathway factors (5)
- X
- V
- II
- I
- XIII
intrinsic pathway factors (4)
- XII
- XI
- IX
- VIII
extrinsic pathway factors (2)
- VII
- tissue factor (III)