More clin path

Question 1

requirements for hemostasis

Answer 1

1. intact and healthy vessels
2. normal platelet numbers
3. normal platelet function
4. normal amount and function of clotting factors

Question 2

petechiae and echymoses

Answer 2

pin point red spots on skin/mucus membranes
indicating problem with platelets

Question 3

megakaryocytes

Answer 3

in bone marrow
pinched off parts of cytoplasm containing granules turns into platelets

Question 4

thromboxane A2 and ADP

Answer 4

activates platelets

Question 5

vonWillebrands factor

Answer 5

platlets bind to receptor on vWF when exposed

Question 6

platelets

Answer 6

from cytoplasm of metakaryocytes
binds to vWF and fibrinogen (cross linking)
+ charge to bind to - charge

Question 7

automated platelet count

Answer 7

hematology analyzer
pro: quick and easy
cons: clumping = false decrease

Question 8

estimated platelet count

Answer 8

stained blood smear
pro: cheap, small sample volume, subjective if clumping
cons: clumping, time and technical skill

look at monolayer under 100x objective
multiply number in field by 15,000

Question 9

thrombopathy

Answer 9

platelets are not working properly
can be extrinsic or intrinsic

Question 10

extrinsic platelet thrombopathy

Answer 10

something from outside the platelet is not working
most common: vonWillebrands disease
diagnosis:
* normal platelet count, PT, PTT
* prolonged buccal mucosal bleeding time (BMBT)
* measure vWF

problem with PRIMARY hemostasis

Question 11

intrinisc hereditary thrombopathy

Answer 11

• uncommon
• various mechanisms
• specialized testing

diagnosis
* bleeding, poor clot formation, normal platelets, normal PT/PTT, normal vWF

Question 12

intrinsic acquired thrombopathy

Answer 12

drugs: COX inhibitors (NSAIDs, steroids), b-lactam antbiotics, calcium channel blockers
uremia (renal failure, toxins in circulation impairs platelets)
DIC: fibrin and fibrinogen in excess interfere with platelts
liver dz
infections

Question 13

thrombocytopenia main causes

Answer 13

Sequestration
Decreased Production
Utilization/consumption
Destruction

SPUD

Question 14

sequestration thrombocytopenia

Answer 14

platelets trapped in spleen
splenomegaly

Question 15

decreased production thrombocytopenia

Answer 15

selective and generalized marrow injury
severy thrombocytopenia

Question 16

utilization/consumption thrombocytopenia

Answer 16

DIC (hypercoagulation forms microclots, then runs out and hemorrhage)
moderate thrombocytopenia
schistocytes/fragmenatation RBCs

Question 17

destruction thrombocytopenia

Answer 17

severe
immune mediated usually
infection, drugs

Question 18

Thrombocytosis causes

Answer 18

Not Neoplasia (Common)
* Physiologic/Excitement (splenic contraction)
* Inflammation (reactive, most common)
* Hemorrhage (regeneration)
* Iron deficiency
* Vincristine
* Glucocorticoids

Neoplasia (rare)
* Essential Thrombocythemia (Chronic megakaryocytic leukemia)
* >1,000,000/uL

Question 19

Where are clotting factors produced?

Answer 19

liver

Question 20

coagulation factor I

Answer 20

fibrinogen

Question 21

coagulation factor II

Answer 21

thrombin

Question 22

coagulation factor III

Answer 22

tissue factor (TF)

Question 23

Coagulation factor VIII 8

Answer 23

factor A

Question 24

coagulation factor IX 9

Answer 24

factor B

Question 25

Intrinsic coagulation pathway

Answer 25

inside the blood vessel initiated by contact with - charged substances (exposed collagen, platelet, endotoxins)

Question 26

extrinsic coag cascade

Answer 26

things outside of the blood vessel (ex tissue factor III)

Question 27

Intrinsic cascade coagulation factors

Answer 27

12 > 11> 9 > 8 | Its not $12, its $11.9

Question 28

common coagulation cascade factors

Answer 28

10 > 5 > 2 > 1

Question 29

common coagulation cascade factors

Answer 29

10 > 5 > 2 > 1

Question 30

extrinsic coag pathway factors

Answer 30

3 > 7

Question 31

vitamin K dependent factors

Answer 31

2, 7, 9, 10

Question 32

which vit k dependent coag factor has the shortest half life?

Answer 32

7 will shoe deficiency first

Question 33

blue top tube

Answer 33

contains citrate, stops clotting

Question 34

coagulation test for intrinsic and common cascades?

Answer 34

Activated clotting time (ACT): not as sensitive, can do at clinic Partial thromboplastin time (PTT): must go to lab

Question 35

coagulation test for extrinsic and common cascades?

Answer 35

Prothrombin time (PT)

Question 36

coagulation test for fibrinogen concentration?

Answer 36

Thrombin time (TT)

Question 37

prolonged PTT/ACT, normal PT

Answer 37

Problems with intrinsic pathway usually hemophilia A (8) or B (9)

Question 38

prolonged PT, normal PTT/ACT

Answer 38

problem with extrinsic pathway factor 7 or 3 (TF) deficiency early vit K deficiency (7 has shortest half life)

Question 39

prolonged TT

Answer 39

**Fibrinogen deficiency**/dysfunction Thrombin inactivation **liver failure, DIC** NOT vit k deficiency

Question 40

Increased PTT/ACT and PT

Answer 40

vit K deficiency (if normal TT) DIC (schistocytes, thrombocytopenia, increased TT, increased D dimers) liver failure (low other liver products- glucose, BUN, albumin, cholesterol)

Question 41

Causes of intravascular coagulation

Answer 41

**Thrombosis:** Initially **unbalanced hemostasis** Virchow’s triad * Stasis of blood flow * Endothelial injury * Hypercoagulability Inciting processes * Congestive heart failure * Heartworm * Protein-losing nephropathy **DIC** Initially **balanced hemostasis** Massive coagulation initiation * **Massive TF exposure or release** Inciting processes * Trauma * Cancer * Shock * Sepsis

Question 42

DIC causes

Answer 42

Initially balanced hemostasis Massive coagulation initiation * Massive **TF exposure or release** Inciting processes * Trauma * Cancer * Shock * Sepsis | **TISSUE FACTOR**

Question 43

Thrombosis causes

Answer 43

Initially **unbalanced hemostasis** Virchow’s triad * **Stasis of blood flow** * **Endothelial injury** * **Hypercoagulability** Inciting processes * Congestive heart failure * Heartworm * Protein-losing nephropathy

Question 44

plasminogen activator

Answer 44

in endothelial cells converts plasminogen into plasmin plasmin chops up fibrin and makes d dimers

Question 45

fibrinogenolysis/fibrinolysis

Answer 45

1. **plasma activator** released from endothelial cells 2. PA cleaves **plasminogen into plasmin** 3. plasmin **breaks down fibrin and fibrinogen** into **D dimers and fibrin degredation factors (FDP)**

Question 46

increased fibrin degredation products

Answer 46

fibrin and fibrinogen degredation products increased when there is plasmin mediated cleavage of fibrinogen/fibrin increase = clot formation and breakdown **suggest DIC**

Question 47

increased D dimers

Answer 47

specific type of fibrin degredation product suggest clot formation and breakdown **suggest DIC**

Question 48

heparin

Answer 48

anticoagulant

Question 49

antithrombin III

Answer 49

**MOST POTENT antihemostasis** protein in body **destroys thrombin** anticoagulant amplified by heparin **lose by: Protein-losing disorders** * Protein-losing nephropathy (PLN) * Protein-losing enteropathy (PLE)