Disorders of Coagulation

Question 1

what are the four rule outs for thrombocytopenia?

Answer 1

consumption
destruction
production
sequestration

Question 2

what are the spontaneous clinical signs of a problem with clotting?

Answer 2

petechiation
ecchymosis
epitaxis
GI hemorrhage
hematuria

Question 3

what can you use to assess platelet function?

Answer 3

platelet aggregometry: not clinically available
buccal mucosal bleeding time
difficult to do

Question 4

what are normal platelet numbers?

Answer 4

200,000-500,000/microL

Question 5

spontaneous bleeding is rare if platelets are above ____________________

Answer 5

40,000/microL

Question 6

how many platelets per high powered field is equal to about 15,000/microL?

Answer 6

one

Question 7

what is buccal mucosal bleeding time prolonged with?

Answer 7

moderate thrombocytopenia
thrombocytopathia
von willebrand’s disease

Question 8

what can lead to loss of platelets and thrombocytopenia?

Answer 8

bleeding
thrombosis
sequestration- trapped

Question 9

what can cause destruction of platelets?

Answer 9

immune mediated thrombocytopenia

Question 10

how common is immune mediated thrombocytopenia?

Answer 10

common

Question 11

what can be seen on physical exam to show spontaneous bleeding?

Answer 11

petechiation, ecchymosis
epistaxis
GI hemorrhage
hematuria
ocular hemorrhage

Question 12

what can be seen on a CBC with immune mediated thrombocytopenia?

Answer 12

severe thrombocytopenia- <15,000/microL
regenerative anemia
leukocytosis- inflammatory state

Question 13

when should you be suspicious of a platelet function defect?

Answer 13

young dogs
platelet type bleeding

Question 14

what is the most common inherited bleeding disorder?

Answer 14

von willebrand disease

Question 15

what can you give to increase von willebrand factor release?

Answer 15

DDAVP (desmopressin)

Question 16

what do you see with secondary hemostatic problems?

Answer 16

cavitary bleeding
hematomas
respiratory: hemoptysos
GI: hematemesis

Question 17

when do PT/aPTT become prolonged?

Answer 17

> 75% of factors lost

Question 18

if you have a prolonged PT and normal aPTT, what could be the problem?

Answer 18

factor VII deficiency

Question 19

which factors are implicated in hemophilia?

Answer 19

factor VIII: A
factor IX: B

Question 20

how is hemophilia transmitted?

Answer 20

sex linked recessive
more common in males

Question 21

what can you give for excessive fibrinolysis?

Answer 21

aminocaproic acid

Question 22

what makes up virchow’s triad?

Answer 22

endothelial damage
hypercoagulability
turbulent blood flow/stasis

Question 23

what diseases are associated with hypercoagulability?

Answer 23

systemic inflammation
loss of endogenous anticoagulants
iatrogenic: corticosteroid use
neoplasia

Question 24

what are some things that cause changes in blood flow?

Answer 24

cardiac disease in cats
immobility or paralysis
compression of vessel by mass
organ torsion: vascular torsion

Question 25

how can we diagnose thrombosis?

Answer 25

index of suspicion: underlying disease physical exam imaging

Question 26

why do we not use thrombolytics that much?

Answer 26

can result in bleeding

Question 27

what is disseminated intravascular coagulation?

Answer 27

coagulopathy associated with severe disease mixed thrombosis and bleeding

Question 28

what is secondary hemostasis?

Answer 28

fibrin clot

Question 29

what is primary hemostasis?

Answer 29

platelet plug

Question 30

what happens in excessive bleeding?

Answer 30

decreased platelet numbers and function decreased clotting factors

Question 31

what is an inherited disorder of primary hemostasis?

Answer 31

von willebrand's disease

Question 32

how many platelets per high powered field are normal?

Answer 32

8-15

Question 33

what does buccal mucosal bleeding time assess?

Answer 33

platelet adhesion and aggregation

Question 34

what can cause decreased production of platelets?

Answer 34

bone marrow disease: aplastic anemia, myelofibrosis, neoplasia drugs, toxins radiation therapy

Question 35

what is directed against platelets in primary immune mediated thrombocytopenia?

Answer 35

autoantibodies

Question 36

are females or males more commonly impacted by ITP?

Answer 36

females

Question 37

how long does it take to respond to immunosuppression with prednisone?

Answer 37

4-6 days

Question 38

what does vincristine do?

Answer 38

increases platelet production by megakaryocytes more rapid platelet count response

Question 39

what can cause acquired thrombocytopathia?

Answer 39

FIP hyperglobulinemia drug induced uremia hypo/hyperthermia sepsis

Question 40

what is impaired in von willebrand's disease?

Answer 40

von willebrand factor mediated platelet adhesion

Question 41

what is von willebrand factor?

Answer 41

major binding protein of platelet stored in platelets and endothelial cells bound to factor VIII mediates contact of platelets with extracellular matrix

Question 42

how many types of von willebrand disease are there?

Answer 42

three I, II, III

Question 43

what does DDAVP do?

Answer 43

stimulates von willebrand factor to release from endothelium

Question 44

what are the types of cavitary bleeding?

Answer 44

hemathrosis hemothorax hemoabdomen

Question 45

if there is a deficiency in factors IX and VIII, what is seen on PT/aPTT?

Answer 45

normal PT elevated PTT

Question 46

which animals are symptomatic for hemophilia?

Answer 46

homozygotes

Question 47

what can lead to loss of endogenous anticoagulants?

Answer 47

PLN PLE

Question 48

what drugs can cause hypercoagulability?

Answer 48

corticosteroids

Question 49

where can venous thrombi occur?

Answer 49

lungs- PTE (pulmonary thromboembolism) legs- DVT (deep vein thrombosis) portal vein- PVT (portal vein thrombosis)

Question 50

what triggers microvascular coagulation in disseminated intravascular coagulation?

Answer 50

systemic inflammation

Question 51

what becomes depleted in disseminated intravascular coagulation?

Answer 51

endogenous anticoagulants clotting factors