Graham Hemostasis 2012 / Exam 2 Flashcards Preview

CVPR 330 Blood > Graham Hemostasis 2012 / Exam 2 > Flashcards

Flashcards in Graham Hemostasis 2012 / Exam 2 Deck (43):
1

Hemostasis

The property of circulation whereby blood is maintained as a fluid within the vessels

2

Four systems of hemostasis ?

* Vascular
* Platelets--Primary Hemostasis
* Coagulation--Secondary Hemostasis
* Fibrinolysis

3

What metabolite induces Vasoconstriction ?

Serotonin and thromboxane A2

4

What metabolite induces Vasodilation ?

Prostacyclin PG I2

5

Name the 7 step of the Hemostatic Plug cascade ?

1.) Vascular Injury
2.) Tissue Exposure
3.) Adhesion
4.) Aggregation
5.) Plug Formation
6.) Fibrin Formation
7.) Clot Retraction

6

Name the 5 step of the Platelet Function cascade ?

1.) Circulating platelets; endothelial damage occurs.
2.) Platelet Adhesion
3.) Platelet Aggregation
4.) Plug Formation
5.) Fibrin Formation
5.) Clot retraction

7

Platelets may become activated by any of several physiologic or pathologic acivators released or exposed a the site of injury. Name 8 of theses activators ?

* Collagen
* Thrombin
* Adenosine Diphosphate (ADP)
* TXA2
* Epinephrine
* Serotonin
* Arginine Vasopressin (AVP or ADH)
* Platelet Activating Factor ( PAF)

8

Platelet activators are counterbalanced by the presence of several inhibitors of activation which include what ?

* Flowing Blood
- Endothelial products
* Prostacyclin (PgI2) &
* Nitric Oxide

9

Injury (or disease) of the vessel endothelium exposes a number of adhesive subendothelial proteins which promotes formation of a platelet plug which adheres to the exposed sub-endothelium. Name the 2 main components ?

* Glycoprotein (GP Ib)
* Von Willebrand factor

10

During Aggregation, platelets adhere to each other to form a plug. Adherent platelets release dense bodies and alpha granules, name the 3 main components ?

* GP IIB
* GP IIIa
* Fibrinogen

11

Recite the sequence of the Prostaglandin pathway?

Membrane Phospholipid

Arachidonic Acid

Prostaglandin Endoperoxides
↓ ↓
PG12 Thromboxane A2

12

Membrane Phospholipid is the substrate for what ?

Phospholipase A

13

Arachidonic Acid is the substrate for what ?

Cyclooxygenase

14

Prostaglandin Endoperoxides are the substrates for what ?

Prostacyclin Synthetase
&
Thromboxane Synthetase

15

What INHIBITS platelet aggregation ?

PG 12

16

What INDUCES platelet aggregation ?

Thromboxane A2

17

2 Primary Hemostatic Disorders?

* Inherited = in the young
* Acquired = Most problematic

18

Without the Prostaglandin Pathway, the platelets . . . .

Will not work

19

4 Inherited Platelet Disorders

* von Willebrand Disease
* Glanzmann’s Thrombasthenia
* Bernard Soulier Disease
* Deficient Release Reaction

20

What is the most common platelet disorder?

von Willebrand Disease

21

What disorder lacks GP IIB
GP IIIa ?
How would you treat this ?

Glanzmann’s Thrombasthenia

Give platelets.

22

Bernard Soulier Disease
lacks what ?

Protein 1b which is necessary for adhesion.

23

4 Acquired Platelet Disorders ?

DRUGS: Ibuprofen
Uremia
Myeloproliferative Disorders

24

Myeloproliferative Disorders

Chronic leukemia's that effects the platelets that the body produces

25

Aspirin has a blocking effect on what portion of the prostaglandin pathway ?

Cyclooxygenase

26

* Screening test for primary hemostasis
* Not a good predictor of surgical bleeding risk
* Very technique-dependent

Bleeding Time

27

Platelet Function Analyzer (PFA)

is the modern “In vitro bleeding time”

28

How can we look at individual affects of different activators on platelets? What test should we order?

Platelet Aggregation Studies

29

Platelet Function Analysis via a bleeding time study would provide what information ?

Platelet number
Platelet function
Vascular integrity

30

Platelet Function Screen via a Platelet Function Analyzer (PFA) study would provide what information ?

* Platelet number
* Platelet function
* vWD
* NSAIDS

31

With the (PFA 100 Principle) Citrated whole blood is aspirated through a capillary towards a membrane that is coated with what agonists that activate platelets?

* Collagen/Epinephrine
* Collagen/ADP

32

Agonists in combination with high shear stresses create an environment where . . .

adhesion, activation, and aggregation can be evaluated.

33

During a PFA interpretation what are the normal values for collagen/Epinephrine ?

94 - 194 sec

34

Abnormal values for Collagen/Epinephrine would indicate what possible platelet disorders?

* Intrinsic platelet defects,
* vWD, or
* platelet inhibiting agents

35

Abnormal values for Collagen/ADP would indicate what possible platelet disorders?

intrinsic platelet defect or vWF

36

During a PFA interpretation what are the normal values for Collagen/ADP ?

71 - 118 sec

37

Cascade system activated by substances released at the time of injury

Coagulation--Secondary Hemostasis

38

Coagulation Factor X III =

Fibrin Stabilizing Factor

Factor XIII deficiency causes hemophilia A

39

During Intrinsic pathway, XII + Surface contact =

XIIa

40

Extrinsic pathway begins with the release of an intracellular lipoprotein, tissue thromboblastin (FACTOR III) by vascular injury outside the vessel. In the presence of Calcium, tissue thromboplastin activates what ?

VII
The thromboblastin factor VIIa complex then activates factor X from the common pathway & factor IX from the intrinsic pathway.

41

In the Common Pathway,
Xa + (Va, phospholipids, & Calcium) =

Prothrombin activator complex which activates prothrombin (Factor II) to Thrombin

42

In the Common Pathway, Thrombin + Fibrinogen (I) =

Long strands of Fibrin

43

In the Common Pathway, Thrombin also activates what other factors?

Factor XIII (fibrin stabilizing factor)
Factor XIIIa &
Calcium
forming an insoluble meshwork that is incorporated into the platelet plug.