B&l: 9. Turnicky : Hemostasis Ii

Front 1

What is the job of plasmin?

What step of hemostasis is this a part of?

Back 1

Plasmin activation is localized preventing systemic destruction of other proteases

Plasmin destroys fibrin, but also V, VIII and fibrinogen

AKA it breaks up the clot, thus it is a part of Tertiary hemostasis

Front 2

what is responsible for turning the soluble form of Fibrin to the insoluble (and more stable crosslinked) form?

Back 2

FXIII

Front 3

What test can tell you that the entire coagulation cascade has been activated (thrombosis/lysis)?

**

Back 3

D-Dimer

note: factor 13 has gone from soluble to insoluble; fibrinogen degredation products are always found in the blood; dimer positive if you have insoluble crosslinked fibers, suspect pulmonary embolism

Front 4

what is an excellent marker for cascade activation, and will show DIC, PE, DVT?

Back 4

D-dimer

Front 5

in rare cases pts can have widespread degradation of fibrinogen that results in what?

Back 5

SEVERE BLEEDING

Front 6

What is the most important inhibitor of coagulation?

**

Back 6

Anti-thrombin III (now called Anti-Thrombin)

Front 7

Plasminogen Activator inhibitors
(such as PAI-1) in addition to activating inhibitors does what?

Back 7

activates protein C

Front 8

What can bind with anti-thrombin and potentate its effect? To what degree does it do this?

**

Back 8

Heparin binds to AT causing a conformational change, enhancing the rate of thrombin/AT complex by a factor of 1000.

Front 9

Decreased levels of anti-thrombin are associated with what?

Back 9

DVT and PE

note: this is why oral contraceptives, surgery, etc are not suggested for older pts, as they will cause an even greater effect

Front 10

Protein C does what? If it is deficient, what problem will be seen?

**

Back 10

Inhibits activity of Va & VIIIa, PAI-1

Deficiencies associated with venous thrombosis.

Front 11

What does protein S do?

**

Back 11

Similar to protein, C

inactivates factor 5 and 8

Front 12

Bleeding from vessels into skin produce either

Back 12

Petechiae: small red spots <3mm


Ecchymosis
Bruises, >3mm, due to blood escaping into SQ tissue

Front 13

Hereditary Telangiectasia
Ehlers-Danlos Syndrome
Marfan Syndrome
Osteogenesis imperfecta
Pseudoxanthoma elasticum

these are all due to what?

Back 13

defects in collagen

Front 14

What level of thrombocytopenia is CRITICAL? why?

***

Back 14

<10K: bleeding into gums, gut, from nose, spontaneous CNS hemorrhage

Front 15

When you have thrombocytopenia, you can have failure of marrow production due to either ineffective or reduced megakaryocytes. Please list a few examples of each

Back 15

Ineffective Megakaryopoiesis:
Myelodysplasia
Alcohol suppression

Reduced Megakaryocytes:
Infiltration with tumor, infection, fibrosis
Aplasia due to drugs, chemicals or radiation

Front 16

What is one of the major causes of thrombocytopenia?

Back 16

Splenic sequestration (pooling in spleen)

Front 17

Idiopathic thrombocytopenia purpura
Alloantibodies (transfusion or pregnancy)
Drugs

cause thrombocytopenia through what mechanism?

Back 17

destruction

Front 18

A 4 year old child is brought to your office with an abrupt onset of bruising and petechiae. Mom is really concerned about what is going on with her child and the only significant history she can think of was a viral infection that happened about 2 weeks ago. What does this child have? What is the cause? Tx?

**

Back 18

Answer: Acute Idiopathic Thrombocytopenia Purpura

Giveaways: Children: 2 to 6 yrs of age
Often follows viral infection by 1 to 3 wks
Abrupt onset of bruising, petechiae

CAUSE: IgG antibody directed against platelet

Tx: Spontaneous remission

Front 19

A 30 year old woman comes to your office with an insidious onset of higher platelet counts. What does she likely have? cause?

**

Back 19

Answer: Chronic Idiopathic Thrombocytopenia Purpura

Giveaways: Young women (20-40 yrs)
Insidious onset with higher platelet counts

CAUSE: Platelet auto-antibodies to GP IIB/IIIA

note: Spleen site of Antibody production and destruction: Splenectomy

Front 20

Thrombocytopenia PurpuraAlloimmune is caused by?

*

Back 20

Antibodies caused by exposure to foreign Antigens after transfusion or pregnancy
Thrombocytopenia 7 to 10 days after red cell transfusion

Front 21

What are the 2 types of heparin induced thrombocytopenia purpura?

Please compare:
Immunologic basis
Onset
Tx
Symptoms

Back 21

Type 1:
-No immunologic basis
-Onset is first few day after drug
-Spontaneous recovery of platelets even if the drug is continued
-Often asymptomatic

Type II:
-Immunologic basis: Antibody to heparin-PF4 complex
-Onset: 5-15 days
-Can See Gangrene

Front 22

If a pt is given heparin and their platelet count drops but then Spontaneous recovery of platelet count even if heparin is continued what type of Thrombocytopenia Purpura did the pt have?

Back 22

Type 1

Front 23

What happens in Heparin Induced Thrombocytopenia Syndrome (HITS)

**

Back 23

pt has Low platelet count, but it is due to clotting occuring in microvasculature

it is due to anti-bodies reacting with Heparin PF4 complex, leading to platelet activation

Front 24

HITS is what type of heparin induced thrombocytopenia purpura?

What is the mechanism behind HITS?

**

Back 24

Type II (remember it is immunological)

Antibody to heparin-PF4 complex

Front 25

What causes a dilutional thrombocytopenia?

Back 25

massive transfusion of packed red cells (greater than 10 to 30 units)

doesn't include platelets, so you have to give a supplement

Front 26

What happens in myelodysplastic syndrome?

Back 26

Bone marrow in MDS will have more megakarypcytes, but they are not effective

(so you will have more platelets, but they aren't good ones)

this is pre-leukemia and is also known as 5q syndrome based on the long arm of chromosome 5 being a common genetic marker

Front 27

EDTA (an anticoagulant)
Giant platelets
and clotted blood samples

can be a cause of what?

Back 27

“pseudo-thrombocytopenia”

pt doesn't really have low platelets, but some other factor such as Giant platelets (recognized as red cells by automated counters) lowers the count

Front 28

this autosomal recessive adhesion defect is seen as bleeding at infancy. It is due to decreased or abnormal GP Ib

Back 28

Bernard-Soulier Disease

Front 29

this autosomal recessive aggregation defect is seen as bleeding at infancy. It is due to absent GPIIb/IIIa on the platelet surface...what is this and what is the job of GPIIb/IIIa?

Back 29

Glanzmann Thrombasthenia

GP IIb/IIIa on platelet surface
Necessary for platelet binding to fibrinogen, aggregation of platelets to one another requires fibrinogen.

Front 30

Chronic renal disease and overuse of ASAs (asprin) can lead to what?

***

Back 30

DECREASED NUMBER OF PLATELETS

Note: ASA (asprin): irreversibly acetylating the cyclo-oxygenase enzyme (COX-1) preventing formation of thromboxane A2 (release mechanism inhibited)

Front 31

Approximately 1% of patients receiving Reopro adversely develop severe ?

Back 31

Thrombocytopenia

Reopro= GPIIa/IIIb inhibitors