Coagulation

Question 1

What are the procoagulant aspects of hemostasis?

Answer 1

1. Platelets: adhesion -> activation -> aggregation

2. Coagulation: Activation -> thrombin formation -> fibrin formation, polymerization, stabilization

Question 2

__________ hemostasis involves the platelet plug, __________ hemostasis involves the fibrin clot.

Answer 2

Primary; secondary

Question 3

What is the membrane receptor for platelet response?

Answer 3

Glycoproteins 1b

Question 4

Describe the process of platelet plug formation

Answer 4

vWF binds platelet (via GP 1b) to subendothelial matrix

Platelets release alpha-granules and dense bodies which activate GP IIb/IIIa receptors on other platelets and cause release of ADP

Fibrinogen connects GP IIb/IIIa receptors of each platelet and flattens the platelets

Question 5

Crosslinking of fibrin monomers is done via factor ______.

Answer 5

XIIIa

Question 6

_________ starts the coagulation cascade in most cases.

Answer 6

Tissue factor

Question 7

What are the regulators of primary hemostasis?

Answer 7

1. NO
2. PGl2
3. ADPase

Question 8

What are the regulators for secondary hemostasis?

Answer 8

1. Serine protease inhibitors (antithrombin)
2. Protein C (controls Va and VIIIa)
3. Fibrinolytic system

Question 9

What could be a result of protein C or protein S deficiencies?

Answer 9

Hypercoaguability

Question 10

___________ promotes coagulation by causing resistance to enzymatic inactivation by the Protein C/S complex.

Answer 10

Factor V Leiden mutation

Question 11

How is the plasminogen activated?

Answer 11

tPA + plasminogen = active plasmin

Question 12

Prothrombin Time screens for the activity of the __________.

Answer 12

Extrinsic coagulation pathway

Question 13

Prothrombin time forms the basis of ______.

Answer 13

International Normalized Ratio (INR)

Question 14

A patient has a PT done and is recorded as a 3 on the INR. What medication might he be on?

Answer 14

Warfarin (anticoagulant)

Longer clot time than normal

Question 15

Partial thromboplastin time screens for the activity of the ___________.

Answer 15

Intrinsic pathway

Question 16

Which takes longer to activate (extrinsic or intrinsic)?

Answer 16

Intrinsic

Question 17

What medication might a patient be on if he is being monitored via PTT?

Answer 17

Heparin

Question 18

What are some clinical manifestations of a primary hemostasis disorder?

Answer 18

1. Mucocutaneous bleeding, petechia

2. Excessive bleeding with trauma

Question 19

What are some clinical manifestations of secondary hemostasis disorders?

Answer 19

1. Soft tissue bleeding

2. Excessive bleeding with trauma

Question 20

A patient with a prolonged PT and PTT is likely to have a (primary or secondary) hemostasis disorder?

Answer 20

Secondary

Question 21

A patient arrives with small petechia on the skin. What type of hemostasis disorder might this be?

Answer 21

Platelet (primary)

Question 22

If a patient has normal bleeding time, PT, and PTT, but experiences excessive bleeding what might you suspect?

Answer 22

Regulatory Hemostasis Disorder

Question 23

T/F: PT screens for platelets, while PTT screens for Coagulation pathway.

Answer 23

FALSE

Both are for coagulation.
PT = extrinsic
PTT = intrinsic

Question 24

What is the dominant clinical manifestation of vWD?

Answer 24

Mucocutaneous bleeding

Question 25

What are the three types of vWD?

Answer 25

Type 1: Quantitative deficiency (partial) Type 2: Qualitative deficiency Type 3: Quantitative deficiency (total)

Question 26

Why would PTT be slightly prolongued with vWD?

Answer 26

Factor VIII is slightly effected because it uses vWF to transport

Question 27

Hemophilia A is a deficiency in factor _____.

Answer 27

VIII

Question 28

What are the major laboratory features of hemophilia A?

Answer 28

Prolonged PTT and decreased Factor VIII

Question 29

What is the major treatment option for Hemophilia A?

Answer 29

Factor VIII concentrates

Question 30

A young child has spontaneous intracranial bleeding and a high PTT number. What might be the diagnosis?

Answer 30

Hemophilia A

Question 31

T/F: Hemophilia A is more likely to affect men.

Answer 31

TRue

Question 32

Hemophilia B involves a deficiency in factor ____.

Answer 32

IX

Question 33

What is the major treatment option for Hemophilia B?

Answer 33

Factor IX concentrates

Question 34

T/F: Platelet disorders will show with an increased bleeding time.

Answer 34

TRUE

Question 35

What is thrombocytopenia?

Answer 35

Having a lack of platelets

Question 36

T/F: Adults are likely to have acute ITP.

Answer 36

FALSE ``` Children = Acute Adult = Chronic ```

Question 37

Describe the pathophysiology of ITP?

Answer 37

Autoantibodies attack the platelet membrane antigens

Question 38

How would you treat ITP?

Answer 38

Corticosteroids and intravenous immunoglobulin

Question 39

ITP may cost someone there ________, while TTP may cost someone there _________.

Answer 39

Spleen; kidney

Question 40

What are the two major clinical manifestations of DIC?

Answer 40

Bleeding from multiple sites and thromboembolic problems

Question 41

What is the most imperative early issue with DIC?

Answer 41

Stop the bleeding

Question 42

What is the sequence of clotting factors activated via the intrinsic pathway?

Answer 42

Factor XII -> Factor XI -> Factor IX

Question 43

In the extrinsic pathway, tissue factor activates factor ___.

Answer 43

VII

Question 44

What changes occur through the common pathway of blood clotting?

Answer 44

1. Activation of Factor X 2. Prothrombin -> thrombin 3. Fibrinogen to fibrin molecules

Question 45

PTT would be measured in patients taking __________. While PT would be measured in patients taking ___________.

Answer 45

Heparin; Caumadin/Warfarin

Question 46

Thrombocytopenia is a ___________ in platelet count. Thrombocytosis and thrombocythemia denote an ________ in platelet number.

Answer 46

Decrease; increase

Question 47

Does bleeding time measure for primary or secondary hemostasis?

Answer 47

Primary (platelets)

Question 48

What are the characteristics of a primary hemostasis disorder?

Answer 48

1. Muccocutaneous bleeding or bleeding with trauma | 2. Prolonged bleed time and thrombocytopenia

Question 49

What are characteristics of a secondary hemostasis disorder?

Answer 49

1. Soft tissue bleeding and bleeding with trauma | 2. Long PT and/or PTT

Question 50

What molecule acts as a carrier protein for Factor VIII until endothelial damage is seen?

Answer 50

vWF