Abnormal hemostasis Flashcards
What does abnormal hemostasis lead to
Hemorrhage or thrombosis
Platelet disorders
-Thrombocytopenia: decreased production, use too much, premature distruction
-Thrombocytopathy: not working right
Causes of decreased platelet numbers
Leads to hemorrhage
-Myelopathies
-Chemicals
-Drugs
-Radiation and chemotherapy
Causes of increased destruction of platelets
-Immune mediated: primary or secondary
-Infection
Causes of increased consumption of platelets
-Endothelial activation
-Localized intravascular coagulation
-Disseminated intravascular coagulation
Inhereted problems of platelets
-Gplb deficiency
-Defective GPIIb and GPIIIa
-Von Willebrand factor deficiency
Von Willebrand disease
Most common inherited bleeding disorder of dogs (corgi, dobermans, german sheperd)
Platelets don’t bind to endothelium
Other causes of thrombocytopathy
-Drugs
-Uremia with renal failure
-Increased FDP
-Hepatic disease
-Immun-mediated thrombocytopenia
-Megakaryocytic neoplasia
-Infection
Antiplatelet drugs
Aspirin
Coagulation disorders
Can ve inherited or acquierd
Inherited coagulation disorders
-Found in every pathway although some may be more rare
-Hemophilia A (Factor VII)
-Hemophilia B (Factor IX)
Hemophilia A
Most common coagulopathy in animals (german sheperd) Factor VIII defieciency
Acquired Coagulation disorders
-Decreased production (liver disease, Vitamin K deficiency)
-Increased utilization (endothelial injury, sever trauma or burns, DIC)
-Inhibition of coagulation factors (heparin, FDP, antiphospholipid antibody, antibody to CF)
Coagulation disorders due to liver disease
-Decreased production of pro and anti coagulant factors
-Must be really severe or DIC to see
Vitamin K dependent coagulation factor
II, VII, IX, and X, and proteins C and S
Vitamin K antagonists
-Moldy sweet clover
-Rodenticides (warfarin)
-Sulfaquinoxaline
Other causes of Vitamin K deficiency
-Anorexia
-Enteric antimicrobials
-Decreased fat digestion or absorption
Causes of DIC
Major stimulus is widespread vascular injury
DIC
Thrombin is the central role
-Activates platelets and coagulation factors and activates fibrinolysis
-Rapid consumption of hemostatic proteins (coagulopathy)
-Later get uncontrolled hemorrhage
DIC morphology
-Subclinical to sever hemorrhage
-Shock
-Organ Failure
Causes of hemorrhage
-Vascular injury
-Platelet disorders
-Coagulation disorders
Causes of vascular injury
-Trauma
-Inflammation
-Secondary invasion
-Necrosis
-Endothelial degeneration (endotoxin)
By rhexis
Active blood loss due to tears or rents in blood vessel
By diapedesis
Passive blood loss through endothelial gaps
Classification of hemorrhage
-Petechia
-Ecchymosis
-Suffusive
Petechia
Pinpoint hemorrhage
Eccymosis
Medium hemorrhage associated with more severe vascular injury
Suffusive
Large localized hemorrhage
Hematoma
Hemorrhage into tissue or interstitium. Eventually stops (confined) when pressure in outside of tissue is same in blood vessel
Thrombosis
Solid mass of blood components within a blood vessel or the heart. Reflection of excessive or inappropriate hemostasis
Causes of thrombosis
-Endothelial activation/injury
-Platelet activation
-Coagulation pathways activated
-Stasis
-Decreased fibrinolysis
-Abnormal anti-coagulant proteins
Virchows triad
-Altered blood vessels
-Altered blood flow
-Altered in blood coagulation
