Chapter 14
what is a normal INR
1
anticoagulant usage should have INR more than
1 ( usually 2-3)
three major steps of hemostasis
1) vasoconstriction 2) platelet plug formation 3) coagulation (clot)
increased activation of the coagulation system is caused by
1. stasis of blood flow 2. procoagulation factors 3. decrease in anticoagulation factors
normal platelet levels
150,000-400,000
the life span of platelets is
7-10 days
Which of the following are NOT commonly associated with bleeding disorders? A: Decreased prothrombin time B: Purpura C: Petechiae D: Bleeding from the gums
A
Which of the following laboratory tests examine clotting time? Select all that apply. A: Prothrombin time B: Activated partial thromboplastin time C: Alanine aminotransferase D: Parathyroid hormone E: Aspartate aminotransferase
A, B
Which of the following is true regarding hemostasis? A: Von Willebrand factor activates fibrin to fibrinogen. B: Platelet plug and clot formation are synonymous. C: Fibrinolysis is the destruction of clots. D: The intrinsic and extrinsic clotting pathways share no common points.
C
clotting time of the intrinsic pathway can be measure by
activated partial thromboplastin time (aPPT)
this is a condition associated w/ the formation of multiple clots.
antiphospholipid syndrome
this is the most common antiplatelet drug
aspirin
main agents to prevent arterial clots area (anticoagulants for venous clots)
aspirin and hydroxyrurea
there is a high prevalence in people with ... for antiphospholipid syndrome
autoimmune disease
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Alcohol abuse and liver damage Clotting disorder OR bleeding disorder
bleeding disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Antibodies against platelets Clotting Disorder OR Bleeding Disorder
bleeding disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Immune Thrombocytopenic Purpura (ITP) Clotting Disorder OR Bleeding Disorder
bleeding disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Petechiae Clotting Disorder OR Bleeding Disorder
bleeding disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Von Willebrand disease Clotting Disorder OR Bleeding Disorder
bleeding disorder
what else is needed for coagulation
calcium and vit K
increase in coag factors: tumor cells may secrete prothrombotic factors
cancer
coagulation is what kind of reaction
cascade
clot formation is balanced by process of
clot dissolution (fibrinolysis)
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Malignant tumors and high estrogen Clotting Disorder OR Bleeding Disorder
clotting disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Primary and secondary thrombocytosis Clotting Disorder OR Bleeding Disorder
clotting disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Smoking and blood flow stasis Clotting Disorder OR Bleeding Disorder
clotting disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Treatments include aspirin and thrombolytic agents Clotting Disorder OR Bleeding Disorder
clotting disorder
This or That? Determine if the characteristics provided are of a clotting disorder or a bleeding disorder. Treatments include heparin and warfarin Clotting Disorder OR Bleeding disorder
clotting disorder
anticoags prolong
clotting time
extrinsic pathway
damage outside vessel
intrinsic pathway
damage to inside of vessel
the following are... (inherited disorders) hemophilia A & B von willebran disease (vWD)
deficiencies in clotting factors
the coagulation pathways are triggered by dif events but do what
end in the same final pathway (synthesizes fibrin)
increase in coag factors: woman 35+ may need to consider other alternatives to oral contraceptives
estrogen
hemostasis has two types of problems associated w/ it
excessive bleeding and clotting
this pathway is stimulated by trauma to a blood vessel occur from external injury (laceration)
extrinsic pathway
secondary hemostasis is
fibrin clot formation
process in which blood clots are dissolved
fibrinolysis
thrombosis is the
generation of an occlusive clot
this suppresses platelet production in bone marrow
hdroxyrurea
the stopping of bleeding
hemostasis
Anticoagulants: these are the characteristics of... activates anti-thrombin (AT) acts to limit the extension of a clot, though it does not prevent clot formation responses vary among people requires careful monitoring with aPTT
heparin
what are the two coag pathways
intrinsic and extrinsic
this pathway is stimulated by tissue damage to the endothelial lining of a blood vessel (inflammation, atherosclerosis) it can also be triggered by stasis of blood (like in AFIB).
intrinsic pathway
the most common acquired deficiency of coag factors occurs in
liver disease (alcoholic cirrhosis)
anticoagulants: these are characteristics of... shorter half-life/fewer side effects than unfractionated heparin activates anti-thrombin (AT) more predictable response usually SUBQ once/twice a day coag monitoring is not required
low molecular weight heparin (LMWH)
what gives rise to platelets
megakaryocytes
enzyme responsible for fibrinolysis
plasmin
primary hemostasis is
platelet plug formation
this is when there's a life-threatening elevation in platelets and they are removed from blood
plateletpheresis
this is used to neutralize bleeding if it occurs on a pt taking heparin *can be given IV and SUBQ
protamine sulfate
step that both pathways end in
the activation of factor x-converts prothrombin to thrombin. and fibrinogen to fibrin
less that 100,000 per microliter is
thrombocytopenia
more that 750,000 per microliter is
thrombocytosis
this is from the liver and stimulates platelet formation.
thrombopoietin.
this can occur in response to injury/ sluggish or stagnant blood flow
thrombus formation
this enzymatically changes plasminogen into plasmin
tissue plasminogen activator tPA
these all describe this which is formed by stasis of blood flow while immobile, sedentary, atrial fibrillation. DVT
venous thrombus formation
In which disorder are fibrin clots formed rapidly, using up coagulation factors, resulting in increased risk of bleeding? A: Primary thrombocytosis B: Immune thrombocytopenic purpura C: Hemolytic-uremic syndrome D: Disseminated intravascular coagulation
D
Which of the following may increase the risk of clotting? A: Use of heparin B: Thrombocytopenia C: Hemophilia diagnosis D: Primary thrombocytosis
D
DVT can cause what
PE
since anti coags prolong clotting time, these should be higher than normal
PT, INR, aPTT
the clotting time of the extrinsic pathway can be measured by
Prothrombin time (PT) or the international normalized ratio (INR)
some coag factors require this for normal function. this deficiency can cause the liver to produce dysfunctional clotting factors
Vit K