Graham Hemostasis 2012 / Exam 2 / 2nd deck

Question 1

How does fibrinogen change to fibrin ?

Answer 1

The enzyme Thrombin converts fibrinogen into Fibrin Monometer, Fibrinopeptide A&B. Fibrin Monometers then connect to each other and form the fibrin clot.

Question 2

1. ) What Lab Test can we run to measure Fibrinogen quantification (see if Fibrinolysis is taking place) ?
2. ) What are the normal values?

Answer 2

1.) D Dimer
2.) 200 - 400 mg/dL
Newborns = 150 - 300 mg/dL

Question 3

Preparation of a Sample for Coagulation Testing ?

Answer 3

• Sodium citrate
• Ratio of blood to
  anticoagulant 9:1
• Tube must be full
• Should not be the first tube drawn

Question 4

Prothrombin Time (PT)

3 minutes @ 37 degrees

Answer 4

• Measures the amount of clotting factors 7, 10, 5, & 2 in the Extrinsic System.

Question 5

Activated Partial Thromboplastin Time (APTT)

5 min @ 37 degrees

Answer 5

(Plasma) + Activator phospholipid + surface contact + Calcium Chloride = Time it takes to clot

Question 6

APTT Normal Lab Value:

Answer 6

25 - 35 sec

Question 7

PT Normal Lab Values:

Answer 7

• Normal Lab Value: 50 - 150 % of normal activity

- Normal Lab Value: 10-13 sec

Question 8

Thrombin Time

3 min at 37 degrees

Answer 8

Test to diagnose Thrombin Inhibition.

- Normal Lab Value: 10-15 sec

Question 9

What study can you use to determine deficiency vs. inhibitor ?

Answer 9

Mixing Study
- Patient plasma is mixed with an equal amount of normal plasma and the APTT is then repeated.

• If the time corrects = Deficiency
• If the time does not correct = Inhibitor is present; heparin or antibody.

Question 10

Plasminogen

Answer 10

Anticoagulant Protein

Question 11

Plasminogen may be activated to the proteolytic enzyme PLASMIN by a number or agents, name 2 of them?

Answer 11

TPA

Urokinase

Question 12

Plasmin

Answer 12

proteolytic enzyme that digests fibrin

Question 13

Explain the D -Dimer test ?

Answer 13

Antibody-d-dimer + Plasma = Positive if Agglutination occurs.

Question 14

Congenital factor deficiencies that may prolong PT ?

Answer 14

I
II
V
X
VII

Question 15

Aquired factor deficiencies that may prolong PT or APTT ?

• May be single factor deficiency or multiple factor deficiency. that my prolong PT ?

Answer 15

• It could be a production problem.

- or a Consumption problem.

Question 16

Inhibitors that may prolong PT ?

Answer 16

• Heparin (some heparins in some test systems)
• Lupus-like anticoagulant (high dose)
• Paraproteins
• Elevated FSP

Question 17

Congenital factor deficiencies

that may prolong APTT ?

Answer 17

I
II
V
X
VIII
IX
XI
XII

Question 18

Inhibitors that may prolong APTT ?

Answer 18

• Heparin
• Specific factor inhibitor
• Lupus-like anticoagulant
• Paraproteins
• Elevated FSP

Question 19

Patient is
Bleeding,
Mixing study corrects Abnormal APTT.

What Factors are deficient?

Answer 19

I
II
V
X
VII (vWF)
IX

Question 20

Patient is
NOT bleeding,
Mixing study corrects Abnormal APTT.

What Factors are deficient?

Answer 20

XI

XII

Question 21

Patient is
Bleeding,
Mixing study does NOT correct Abnormal APTT.

What’s the problem?

Answer 21

INHIBITORS

• Heparin
• Specific factor inhibitor
• Paraproteins
• Elevated FSP

Question 22

Patient is
NOT bleeding,
Mixing study does NOT correct Abnormal APTT.

What’s the problem?

Answer 22

LLAC

Question 23

Factors that may prolong the Thrombin Time ?

Answer 23

• Decreased fibrinogen
• Abnormal fibrinogen
• Thrombin Inhibitors
  Heparin
  Paraproteins
  Increased FSP

Question 24

What is the most common congenital bleeding disorder ?

Answer 24

von Willebrand Disease

Question 25

Criteria for diagnosis of LUPUS

Answer 25

- Prolongation of PT / PTT - Uncorrectable prolongation of the PT / PTT with addition of normal plasma. - Absence of specific inhibitory activity against any specific coagulation inhibitor

Question 26

Natural Anticoagulants

Answer 26

- Antithrombin - Protein C & Protein S - Tissue factor pathway inhibitor

Question 27

What natural anticoagulant neutralizes serine proteases ?

Answer 27

Antithrombin

Question 28

What natural anticoagulant inhibit Va and VIIIa ?

Answer 28

Protein C & Protein S

Question 29

What natural anticoagulant neutralizes VIIa and Xa ?

Answer 29

Tissue factor pathway inhibitor

Question 30

Thrombotic Complications in CPB

Answer 30

- Consumptive and hemodilutional losses of natural anticoagulants - Transfusion of hemostatic products can result in excessive thrombin generation - HIT - Inherited hypercoagulable states

Question 31

Heparin Induced Thrombocytopenia (HIT)

Answer 31

- 1-5% of pts exposed to unfractionated heparin will develop HIT. - 30% of those will develop thrombosis - Patient forms antibodies to the complex of heparin with PF4 found in the alpha granules of platelets

Question 32

Name 5 Inherited Hypercoagulable States?

Answer 32

- Factor V Leiden - Prothrombin G20210A - Elevation of vWF, VIII, fibrinogen - Deficiency of natural anticoagulants - Increased levels of Lipoprotein (a) inhibits fibrinolysis

Question 33

Disseminated Intravascular Coagulation (DIC) definition ?

Answer 33

Secondary condition that results in the increased generation of thrombin. Making clots leads to fibrinolysis (the breaking down of clots) which leads to a vicious cycle.

Question 34

Disseminated Intravascular Coagulation (DIC) fibrinolytic example ?

Answer 34

Hemorrhagic PurpuraMeningococcal Septicemia

Question 35

Disseminated Intravascular Coagulation (DIC) Thrombotic example ?

Answer 35

GangreneHaemophilus B Septicemia

Question 36

Thrombin Removes fibrinopeptides A and B, forming fibrin monomers which results in ?

Answer 36

Decreased Fibrinogen

Question 37

Thrombin Activates V, VIII, and XIII. As it is formed, it consumes what ?

Answer 37

factor II

Question 38

Thrombin also Stimulates platelets, which leads to what ?

Answer 38

thrombocytopenia

Question 39

Activation of Fibrinolysis leads to 4 things, what are they?

Answer 39

- Increased plasmin generation - Lysis of clots - Consumption of fibrinogen - Increased levels of FSP and D-Dimer

Question 40

Laboratory Results in DIC

Answer 40

``` ↑ PT, PTT, TT ↑ Fibrin Split Products ↓ Fibrinogen ↓ Platelets - Schistocytes on peripheral smear ```

Question 41

6 Conditions Associated with DIC?

Answer 41

- Infections - Obstetric complications - Surgery, including CPB - Malignancies - Massive tissue injury - Snakebite

Question 42

Anticoagulant Therapy

Answer 42

* Thrombin Inhibitors - Heparin - Direct thrombin inhibitors * Warfarin compounds (Coumadin) * Antiplatelet therapy