Hemostasis Flashcards
(99 cards)
1
Q
what are the 3 parts to hemostasis?
A
- Primary hemostasis
- Secondary Hemostasis
- Anticoagulation
2
Q
What is the main Factor in Hemostasis?
A
platelet
3
Q
what is part 1 of hemostais and what if the main objective
A
Primary hemostasis
Platelet plug
4
Q
what is part 2 of hemostasis and what if the main objective
A
Secondary Hemostasis
Fibrin production
5
Q
what is part 3 of hemostasis and what if the main objective
A
Anticoagulation
break down clot
6
Q
Steps in primary Hemostasis:
what are the 3 steps in primary hemostasis?
A
- Adhesion
- Activatiion
- Aggregation
ALL A’s
7
Q
Steps in primary Hemostasis:
How is Adhesion accomplished?
A
Adhesion of platelets to damaged vascular wall
8
Q
Steps in primary Hemostasis:
Adhesion of the platelets requires what hemostasis factor
A
vWF (VIII)
9
Q
Steps in primary Hemostasis:
how is activation accomplished?
A
activation of platelets requires thrombin (factor IIa)
10
Q
Steps in primary Hemostasis:
how is aggregation accomplished?
A
aggregation of platelets requires ADP and thromboxane A2
11
Q
Steps in primary Hemostasis:
again the main ingrediant to all hemostasis is what?
A
the platelet
12
Q
Steps in primary Hemostasis:
what is required for adhesion
A
vWF
13
Q
Steps in primary Hemostasis:
what is required for activation?
A
thrombin (IIa)
14
Q
Steps in primary Hemostasis:
what is required for aggregation
A
ADP
Thromboxane A2
15
Q
Adhesion of Platelets:
what is platelets life span
A
8-12 days
16
Q
Adhesion of Platelets:
normal platelet count
A
150,000-400,000 cells/mL
17
Q
Adhesion of Platelets:
Approx 33% of platelets are sequestered where?
A
Spleen
18
Q
Adhesion of Platelets:
what factor Adheres platelets to the collogen layer of the subendothelium?
A
vWF
19
Q
Adhesion of Platelets:
vWF is synthesized and reeased from where?
A
endothelial cells
20
Q
Adhesion of Platelets:
the illistration show vWF anchoring platelets to the wall of a damaged blood vessel.
this is the adhesion aspect of the primary hemostasis
A
21
Q
Adhesion of Platelets:
Magnified look at how vWF anchors platelets
A
22
Q
Adhesion Disorders:
what is the most common inherited coagulation defect
A
von Willebrands disease
23
Q
Adhesion Disorders:
what is the 1st line treatment for von Willebrands disease
A
D-amino-D-arginine vasopressin (desmopressin, DDAVP)
24
Q
Adhesion Disorders:
how does DDAVP work
A
causes release of endogenous stores of vWF
25
Adhesion Disorders:
what is the dose of DDAVP
0.3 mcg/kg IV over 10-20 min
26
Adhesion Disorders:
with DDAVP administration platelet adhesion is increased within how long
30 min
27
Adhesion Disorders:
DDAVP can cause what in type 2B von WIllebrands disease
thrombocytopenia
28
Adhesion Disorders:
vWF can be increased by giveing DDAVP as well as what other 2 drugs?
Cryoprecipitate
Purified factor VIII
29
Adhesion Disorders:
Cyo cantains what coag factors
I
VIII
XIII
(1,8,13)
30
Adhesion Disorders:
if a pt does not respond to DDAVP what should be given next
cryo
31
Adhesion Disorders:
again what are 3 treatments for von Willebrands disease
DDAVP
Cryo
Purified Factor VIII
32
What is the 2nd step of PRIMARY hemostasis?
Activation
33
Activation of Platelets:
what is the mechanism in which a platelet becomes activated?
Thrombin (IIa) combines w/ thrombin receptor on the platelet surface
a process ensues and the platelete changes shape and releases mediators
The main 2 mediators are Thromboxane A2 and ADP
(these will later promote aggregation)
34
Activation of Platelets:
what is the most important molecule in teh activation of platelets
Thrombin
35
Activation of Platelets:
what are the 2 mediators released from platelet activation
ADP
Thromboxane A2
36
Activation of Platelets:
what do Thromboxane A2 and ADP do?
uncover Fibrinagen (I) receptors (more secefic GPIIb/IIIa)
37
Activation of Platelets:
see the picture as a reference. Note the shape change and the release of mediators
38
Activation of Platelets:
what is the precurser to Thrombin?
prothrombin II
once activated becomes IIa Aka thrombin
39
what is the 3rd step in primary hemostasis?
Aggregation of platelets
40
Aggregation of Platelets:
what is teh main molecule that is responsiable for aggregations platelets?
Fibrinogen (I)
41
Aggregation of Platelets:
\_\_\_ and ____ uncover the fibrinogen recetors on the actvated platelets
TXA2
ADP
42
Aggregation of Platelets:
once the receptors are uncovered fibrinogen atteches to it's receptors and links platets to what?
other platelets
43
Aggregation of Platelets:
at this point when the fibrinogen is adhearing platelets to other platelets the developing clot in water soluble and firable and it is termed what 3 things
Platelet plug
white thrombus
white clot
44
Aggregation of Platelets:
check out the picture
45
Aggregation Disorders:
with aspirin the acetylation of platelet cyclooxygenase persist for how long?
the life of the platelet 8-12 days
46
Aggregation Disorders:
what is the rate limiting enzyme in the conversion of arachidonic acid to TXA2
cyclooxygenase (COX)
47
Aggregation Disorders:
without _____ platelete aggregation in impaired
TXA2 (thromboxane A2)
48
Aggregation Disorders:
NSAIDs such as ketorolac and ibuprofen produce the same effects as aspirin, but the depressin of Thromboxane A2 production by platlets if temporary. How long is it for
24-48 hours
49
Aggregation Disorders:
How does Clopidogrel (plavix) work to cause coagulation
anti ADP agent
works the life of platelet
50
Aggregation Disorders:
what antiplatelet medication increases cAMP in platelets and thus prevents aggrigation?
Dipyridamole (persantine)
also is classified as a PDE-I inhibitor
51
Aggregation Disorders:
What receptors do Anti-fibrinogen receptor drugs work on
GPIIb/IIIa
52
Aggregation Disorders:
how do anti-fibrinogen receptor drugs work?
the "cap" and block the fibrinigen receptor, thus preventing fibrinogen from attaching and linking platelets together.
53
Aggregation Disorders:
what are 3 anti-fibrinogen receptor drugs in use
* Eptifibatide (integrilin)
* Abciximab (ReoPro)
* Tirofiban (aggrastat)
54
what is the second part of hemostasis? not primary hemostasis but hemostasis in general?
secondary hemostasis
55
What is the main goal of 2ndary hemostasis?
Production of fibrin
56
Secondary hemostasis:
fibrin production involves what?
all of the clotting factors
57
Secondary hemostasis:
name the cloting factors
1. Fibrinogen
2. prothrombin
3. tissue factor
4. calcium
5. Proacceleration
6. NONE
7. proconvertin
8. vWF & Antihemophiliac factor
9. christmas factor
10. stuart-prower factor
11. Plasmin thromboplastin antecedent
12. Hagamen factor
13. Fibrin stabilizing factor
58
Secondary hemostasis:
what are the vit K dependent factors
2
7
9
10
C
S
59
Secondary hemostasis:
what is Factor I (fibrinogen) once activated (Ia) called
Fibrin
60
Secondary hemostasis:
After platelets aggregate ___ is woven into platelets and cross-linked.
Fibrin
61
Secondary hemostasis:
the cross linked fibrin is _____ in water
Insoluble in water
62
Secondary hemostasis:
After platlets aggregate, fibrin is woven into platelets and cross linked, the crosslinked fibrin is insoluble in water. thus the fibrin clot is now stable. The clot is now called what 2 things
red thrombus
red clot
63
Secondary hemostasis:
cross linking of fibrin strands requires what factor
XIIIa
Fibrin stabilizing factor
64
Secondary hemostasis:
the final steps in fibrin prouction involve what pathways
Intrinsic
Extrinsic
Final common
65
Secondary hemostasis:
heres a picture
66
Secondary hemostasis:
here is a colored picture
67
Secondary hemostasis:
what type of bond stabilizes the fibrin network
Covalent
68
Secondary hemostasis:
so we learned about cryo earlier now why is cryo an important drug for coagulation?
* Factor (I) Fibrinogen (Ia) fibrin- causes crosslinking
* VIII vWF- promotes platelet adhesion
* XIII Fibrin stabilizing factor- forms covalent bond at cross-linked areas stabilizing the fibrin clot
69
Secondary hemostasis: Coagulation Cascade
what factors are in the extrinsic pathway?
III- Thromboplastin or tissue factor
VII- proconvertin
70
Secondary hemostasis: Coagulation Cascade
where does damage occur is the extrinsic pathway is activated
outside the cell
71
Secondary hemostasis: Coagulation Cascade
what factors are in the intrinsic pathway?
XII- hagamen
XI- Plasma thromboplastin
IX- christmas
VIII- vWF
72
Secondary hemostasis: Coagulation Cascade
the ending factors in both the intrinsic and extrinsic pathways combine with what factor to go to factor 10 in the common fina pathway
IV calcium
73
Secondary hemostasis: Coagulation Cascade
what factors are in the final common pathway
X
V
II
I
XIII
74
Secondary hemostasis: Coagulation Cascade
what factors are Ca++ dependent factors
2,7,9,10
same as Vit K dependent factors
75
Secondary hemostasis: Coagulation Cascade
what drug works on the extrinsic pathway?
what labs monitor it?
Coumadin
PT/INR
76
Secondary hemostasis: Coagulation Cascade
what drug works on the intrinsic pathway? what labs monitor it?
Heparin
PTT
ACT
77
Secondary hemostasis: Coagulation Cascade
my drawing of the pathway
78
Secondary hemostasis: Coagulation Cascade
what pathway does cryo mostly work on and why?
Common final pathway
b/c it has factors 1,8,13 and 1 and 13 are both in the final pathway
79
Secondary hemostasis: Coagulation Cascade
Valley's picture
80
Congenital Disorders of Coagulation:
hemophilia A affects what factor
VIII:C deficiency
81
Congenital Disorders of Coagulation:
treatment for Hemophilia A
FFP and Cryo (both have VIII
Factor VIII concentration
82
Congenital Disorders of Coagulation:
What factor deficiency causes hemphilia B
AKA Christmas disease
IX
83
Congenital Disorders of Coagulation:
treatment of Hemophilia B Christmas disease
Heat treated concentration of factor IX
84
Anticoagulation:
how does antithrombin work
Activated antithrombin binds to thrombin (IIa) and factor Xa greatly
By attaching to these clotting factors esp thrombin and Xa antithrombin effectivly removes them from circulation
thus anticoagulating blood
85
Anticoagulation:
what drug works by increasing the effectivness of antithrombin by 1,000 fold or more?
heparin
86
Anticoagulation:
besides IIa and Xa what other factors does antitrhombin work on
IX
XIa
XIIa
87
Anticoagulation:
Antithrombin is made in the liver and neutralizes the final pathway by what factors? and the intrinsic pathway by what factors?
Common IIa and Xa
Intrinsic XIIa, XIa, and IX
88
Anticoagulation:
what is a required cofactor for heparin to work
antithrombin
89
Anticoagulation:
aquired anithrombin def states are found in what type of patients
cirrhosis of liver
Nephrotic syndrome
90
Anticoagulation:
what is the most common reason a pt is unresponsive to heparin
antithrombin def
91
Anticoagulation:
if someone is unresponsive to heparin what would u give them and why?
FFP
it comtains all coagulation and anticoagulation factors produced by the liver
92
Anticoagulation:
heparin block what pathway(s)
Intrinsic and common
93
Anticoagulation:
protamine reverses the effects of heparin how?
neutralization
94
Anticoagulation: fibrinolysis
what breaks down fibrin
Plasmin
95
Anticoagulation: fibrinolysis
what is converted into plasmin to break down fibrin
Plasminogen
96
Anticoagulation: fibrinolysis
after plasminogen is converted into plasmin and plasmin starts to breakdown fibrin, what are the fibrin degradation products refered to as
Fibrin split products
97
DIC:
what are the most common precipitating factors in the surgical pt
Shock
Ischemia
and infection
98
DIC:
what happens to lab values
Platelets
Fibrinogen
Prothrombin
Factors V, VIII, XIII
Fibrin split products
Platelets- decreased
Fibrinogen- decreased
Prothrombin- decreased
Factors V, VIII, XIII- decreased
Fibrin split products- Increased
99
Memory master pages
IA8a-e
IB13
