Coagulation Flashcards

1
Q

What are the three layers of a blood vessel?

A

Intima, Media, Adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of cells make up the intima?

A

primarily endothelial, some elastic and connective tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which type of blood vessels (arteries, veins, capillaries) only have intima?

A

capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which layer of blood vessels are made up of smooth muscle, collagen and elastic tissues?

A

media (middle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Disruption of which tissue type activates the clotting cascade?

A

collagen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does collagen do to platelets during the coagulation cascade?

A

anchor platelets to the vasculature wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which layers of blood vessels are under the influence of vascular mediators?

A

media and adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the outer layer of blood vessels, made up of connective and elastic tissue?

A

adventitia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the two functions of endothelial cells?

A

separates fluid from highly thrombotic material that lies beneath
synthesize and secrete procoagulants, anticoagulants, fibrinolytics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the procoagulants, anticoagulants, fibrinolytics secreted by endothelial cells?

A

Von Willebrand Factor, Tissue Factor
Tissue Factor Pathway Inhibitor
TPA, Urokinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does Von Willebrand factor do when secreted from endothelial cells?

A

adheres platelets to the subendothelial layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does tissue factor do when secreted from endothelial cells?

A

activates the clotting cascade

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does tissue factor pathway inhibitor do when secreted from endothelial cells?

A

aids in suppression of coagulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are TPA and Urokinase, and what do they do when secreted from endothelial cells?

A

Fibrinolytics.

activate plasminogen and initiates the process of fibrinolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When there is disruption to the endothelial lining, what happens to the vessel wall?

A

Contracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 mediators of vessel tone?

A

Thromboxane A2 and ADP

Nitric oxide and Prostacyclin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does Thromboxane A2 and ADP do to the vessel wall?

A

Vasoconstricts, released from platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does Nitric oxide and Prostacyclin do to the vessel wall?

A

Vasodilation. Released from surrounding endothelial cells to divert blood flow to other areas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where are platelets formed?

A

megakaryocytes in bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Hemostasis is not possible without an adequate number of what?

A

platelets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How do platelets arrive at the site of injury so quickly?

A

They flow towards the edges of blood vessels due to their size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Why aren’t platelets constantly clotting blood vessels?

A

they are largely inactive until stimulated by trauma or plaque disruption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How are platelets different from whole cells?

A

Both contain mitochondria, actin, myosin. Platelets do not contain a nuclei and cant reproduce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do platelets produce that activates other platelets to facilitate clumping?

A

thrombin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What do the alpha and dense granules in platelets do?

A

store proteins and non proteins, synthesize prostaglandins promoting vascular and tissue reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the three steps to clot formation/platelet plug?

A

Adhesion, Activation, Aggregation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What occurs during Adhesion stage?

A

vWF attaches to Gp1b receptors on the platelet surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What does vWF do to strengthen the forming clot?

A

attracts more platelets to the site of injury and increases their adhesion ability (stickiness)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What occurs during the Activation stage?

A

Platelets undergo conformation change to activated form

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the conformational changes platelets undergo during activation?

A

Disk to oval

Develop spiky protrusion to aid in stickiness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

During Activation: what are the 2 mechanism that activate phospholipase C?

A

Platelet binding to vWF initates “outside in” signaling to activate phospholipase C
Tissue factor, thrombin, ADP, TxA2 stimulate GPCR that signal more activation of phospholipase C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

During Activation, what are the two things actually responsible for changing the shape of platelets?

A

Phospholipase C and calcium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What occurs during the Aggregation step to form an initial platelet plug?

A

GpIIb and GpIIIa receptors (for fibrinogen/fibrin) on platelet surface change shape and link platelets together with fibrinogen/fibrin

34
Q

What does activated phospholipase C do during Aggregation?

A

initiates the “inside out” signaling that stimulates the change in GpIIb/IIIa receptors to allow binding with fibrinogen and fibrin

35
Q

What does ADP and thromboxane A2 do during the Aggregation step?

A

act on nearby platelets to stimulate adherence to one another

36
Q

What Factors are Vitamin K dependent?

A

2, 7, 9, 10

37
Q

What blood clotting factors do not come from the liver?

A

3 and 4

38
Q

What blood clotting factors are in the intrinsic pathway?

A

12, 11, 9, 8

39
Q

What blood clotting factors are in the extrinsic pathway?

A

3, 7

40
Q

What blood clotting factors are in the common pathway?

A

10, 5, 2, 1, 13

41
Q

What activates the extrinsic pathway?

A

activated when traumatized vessels/tissues come in contact with blood

42
Q

How is the intrinsic pathway activated?

A

activated by exposure of blood to collaged in traumatized vessels

43
Q

Where do the intrinsic and extrinsic pathways merge?

A

Factor X (10)

44
Q

State the steps in the Intrinsic pathway.

A

Initiated by platelet phospholipids and activation of Hageman factor (XII)
XII activates plasma thromboplastin antecedent (XI), which activates Christmas (IX), which activates antihemophiliac (VIII)
VIII, IX, calcium, and platelet phospholipids work together to activate X

45
Q

What is considered rate limiting step in blood coagulation?

A

Factor 10 and 5 forming prothrombin activator

46
Q

What causes a clot to retract?

A

action of contractile proteins and calcium within the platelet

47
Q

State the steps in the Extrinsic Pathway.

A
Tissue factor (III) is released which forms a complex with proconvertin (VII) in the presence of calcium; activates X
Tissue factor pathway inhibitor immediately begins to inhibit tissue factor (III)
48
Q

State the steps in the Common Pathway

A

Factor 10, Along with factor V forms prothrombin. Prothrombin is converted to thrombin.
Thrombin converts Fibrinogen into Fibrin
Fibrin with factor 13 form a stable fibrin clot

49
Q

What acts as a positive feedback mechanism within the clotting cascade?

A

Thrombin

50
Q

What factor activates factor 13?

A

thrombin (2a)

51
Q

What factors does thrombin activate?

A

5, 7, 8, 11, 13

52
Q

What are some important things thrombin does?

A

Recruits platelets to the site of injury
accelerates clot retraction
prevents excess clot formation

53
Q

What happens when thrombin activates protein C?

A

inactivates factors 5 and 8

54
Q

What does protein S do to protein C?

A

increases the ability of Protein C

55
Q

Which factors activate fibrinolysis?

A

tissue plasminogen activator (tPA), Urokinase, Factor 11a, 12a, kallikrein

56
Q

What factors inhibit fibrinolysis?

A

Plasminogoen activator inhibitor 1 and 2 (inhibits tPA and urokinase), alpha2 antiplasmin, alpha2 macroglobulin, thrombin-activatable fibrinolysis inhibitor

57
Q

How does plasminogen get converted to plasmin?

A

tPA, urokinase, factor 11a, factor 12a, kallikrein

58
Q

What helps to breakdown fibrin into fibrin degradation products?

A

Plasmin

59
Q

What stops the breakdown of fibrin into fibrin degradation products?

A

thrombin-activatable fibrinolysis inhibitor

60
Q

What is the normal platelet count?

A

150-300

61
Q

what is the normal bleeding time?

A

3-7 minutes

62
Q

What does bleeding time measure?

A

capability of contraction in the microvasculature, function of platelets

63
Q

What is the normal prothrombin time?

A

10-12 seconds

64
Q

What is the normal and therapeutic INR?

A

normal 0.9-1.2

Therapeutic 1.5-3

65
Q

What is the normal aPTT?

A

25-38 seconds

66
Q

What is the normal ACT?

A

90-150 seconds

67
Q

What is the normal thrombin time?

A

9-35

68
Q

What is the normal fibrinogen assay? what increases it?

A

200-400 mb/mL. Pregnancy

69
Q

What is the normal fibrin degradation products and D dimer?

A

0-11 and < 500 ng/mL

70
Q

What is the most essential regulator of erythropoietin and RBC production?

A

tissue oxygenation

71
Q

What are some important components for RBC production?

A

vitamin B12, folic acid, iron, and kidney function

72
Q

What do RBCs contain that converts H2O and CO2 to H2CO3?

A

carbonic anhydrase

73
Q

How do you calculate oxygen bound to hemoglobin?

A

Hgb x 1.34 x O2 sat

14 x 1.34 x .95 = 17.82

74
Q

How do you calculate oxygen dissolved in blood?

A

PaO2 x 0.003

PaO2 88 x 0.003 = 0.26

75
Q

How do you calculate total oxygen content?

A

O2 bound to Hgb + oxygen dissolved in blood

76
Q

How do you calculate the amount of CO2 dissolved in blood?

A

PaCO2 x 0.067
40 x 0.067 = 2.68
If given EtCO2 add 5-10 to get PaCO2

77
Q

How do you calculate MABL?

A

MABL = EBV x (Hct-mHct)/Hct

78
Q

how much blood does a 4x4 hold?

A

10mL of blood

79
Q

How much does a Ray-tech hold?

A

10-20mL blood

80
Q

How much do Lap sponges hold?

A

75-150mL blood

81
Q

What are the average blood volumes for neonate for adults?

A
premature 95mL/kg
full term neonate 85 mL/kg
infant 80mL/kg
male 75mL/kg
female 65mL/kg
use ideal for obese