Coagulation pathways Pathway

Question 1

The extrinsic pathway is inhibited by which drug?

Answer 1

Warfarin

Question 2

Extrinsic pathway is activated by ?

Answer 2

Vascular injury or when vessel wall comes into contact with blood.

Question 3

Extrinsic pathway is measured by?

Answer 3

PT and INR

Question 4

List the three steps of the extrinsic pathway

Answer 4

1. Tissue factor release
2. Factor 10 activation
3. Prothrombin Activator (Prothrombinase)

Question 5

Explain the steps of the extrinsic pathway

Answer 5

1. Tissue trauma liberates TF from the subendothelium
2. TF activates factor 7
3. Factor 7 activates factor 10 in the presence of Ca
4. Prothrombin activator and platelet phospholipids activate factor 2 ( thrombin)
5. 5 is a positive feedback mechanism that accelerates the continued production of prothrombin activator

Question 6

The extrinsic pathway is fast and requires only _______

Answer 6

15 seconds

Question 7

Prothrombin activator is?

Answer 7

A collective name that refers to the collection of coagulation factors that lead to thrombin activation 2a

Question 8

Which factor is the first to be deficient in patients with liver disease and why?

Answer 8

Factor 7 since it has the shortest half life of all the coagulation factors (4-6hrs)

Question 9

What is the half life of factor 7 ( antihemophilic factor)

Answer 9

4- 6 hrs

Question 10

Intrinsic pathway is activated by?

Answer 10

Blood trauma

Question 11

PTT and ACT measures which pathway?

Answer 11

Intrinsic pathway

Question 12

Intrinsic pathway includes which factors?

Answer 12

12, 11, 9, 8

Count backward from 12 skipping 7

Question 13

________. pathway is inhibited by heparin

Answer 13

Intrinsic

Question 14

___________ is also called contact activation pathway?

Answer 14

The classical intrinsic pathway.

Question 15

What is the first step of the intrinsic pathway

Answer 15

Blood trauma exposes collagen activating factor 12

Question 16

What is the second step of the intrinsic pathway

Answer 16

Factor 11 activation

• Factor 12a activates 11
• Step requires HMW kinogen
• Step accelerates prekallikrein

Question 17

What is the third step of the intrinsic pathway

Answer 17

Factor 9 activation- Factor 11a activates factor 9

Question 18

What is the fourth step of the intrinsic pathway

Answer 18

Factor 10 activation

• Factor 9a and 8 activate 10
• Factor 8 is missing with hemophilia A
• Platelets are missing with thrombocytopenia

Question 19

What is the 5th step of the intrinsic pathway

Answer 19

Prothrombin Activator (prothrombinase)

• Prothrombin activator and tissue phospholipids activate thrombin (factor 2a)
• This step in the intrinsic pathway is identical to the last step of the extrinsic pathway

Question 20

The intrinsic pathway is slower requiring up to _________ minutes to form a clot

Answer 20

6 minutes

Question 21

The primary goal of both the intrinsic and extrinsic pathway is?

Answer 21

To produce prothrombin activator (prothrombinase)

Question 22

The final common pathway begins when?

Answer 22

Begins when prothrombin activator changes prothrombin (2) to thrombin (2a)

Question 23

__________ is a proteolytic enzyme that changes fibrinogen to fibrinogen monomer

Answer 23

Thrombin (2a)

Question 24

After platelets aggregate , _______ is incorporated into the platelet plug

Answer 24

fibrin

Question 25

The clot stays in place until ______________

Answer 25

the underlying vascular tissue has repaired itself

Question 26

Prothrombin activator (prothrombinase) is a complex of?

Answer 26

10a + 5a + 4

Question 26

Prothrombin activator (prothrombinase) is a complex of?

Answer 26

10a + 5a + 4