Hemolymph- EXAM 1/Midterm: Bleeding Disorders LEC3

Which 2 breeds are predisposed to physiological thrombocytopenia?

-cavalier king charles spaniels

-greyhounds

True or False- Vaccines, drugs(TMZ), stress, and infections can trigger idiopatic thrombocytopenia.

true

Which term describes non-functioning platelets?

thrombocytopathia

Petechiae are only seen in which of the following conditions?

thrombocytopenia

True or False- Petechiae are only seen with thrombocytopenia with levels below 20 X 10^9

true

Platelet-endothelial interactions characterize _______ hemostasis.

primary

In health, endothelium is a(an) _______ surface.

non-adhesive

Endothelium is ____ charged, which repels cells to the center of the vessel.

negatively

In chronological order, what are the steps to clot formation by platelets?

-adhesion

-activation

-aggregation

Subendothelial exposure of which 2 of the following cause platelets to adhere to endothelium?

-vWf and collagen

Re-bleeding occurs ____ after clot formation if coagulation factors are not present/functional.

2-6 hours

True or False- Early rebleeding is classic for anticoagulant rodenticide toxicity.

true

Von Willebrand factor is located in which 3 areas?

-plasma

-alpha granules in platelets

-WPB (weibel palade bodies) in endothelial cells

(plasma, subendothelium, storage granules)

Von Willebrand factor (VWF) is essential for ____ of fast flowing platelets.

deceleration

VWF protects which clotting factor from destruction?

factor 8

Decreased factor 8 will result in a ____ aPTT time.

prolonged

_____ von Willebrand disease (VMD) is mild, with all multimers decreased.

type I

In _____ VWD, all multimers are absent and disease is severe.

type III

True or False- Functional changes in hemostasis occur in Type II VWD.

true

Which cells release pro-angiogenic cytokines and growth factors to maintain endothelial junctions?

platelets

Petechiae occur due to ______ extravasation of RBCs at inter-endothelial junctions.

post-capillary

Which of the following has the tightest endothelial junctions?

brain

Anti-platelet drugs interfere with which 2 of the following?

-thromboxane

-ADP (adenosine diphosphate)

Which 2 of the following are treatment options for ITP?

-immunosuppression

-vincristine

True or False- Fresh/stored platelets can treat ITP but are impractical and don't last long.

true

Limiting future vaccines and a _______ trial may be useful in treating ITP.

doxycycline

Creation of a fibrin clot is the _______ of primary hemostasis.

endpoint

Anticoagulant rodenticide blocks vitamin K1 reductase, which makes which 4 of the clotting factors non-functional?

2, 7, 9, 10

Which clotting factor has the shortest half life?

7

Which of the following are the 3 types of rodenticide?

-anticoagulant

-vitamin D

-bromethalin

Which coagulation test has a 50% error rate?

Buccal mucosal bleeding time (BMBT)

True or False- A BMBT should only be performed if PT, APTT, and platelet counts are normal.

true

A prothrombin time (PT) test evaluates which 4 clotting factors for functionality?

2, 7, 9, 10

aPTT will be ______ after both intrinsic and extrinsic coagulation pathways have been affected.

prolonged

When testing for coagulation ability, which test will be prolonged first?

PT

Activation of factors 12, 11, 9, and 8 start the _____ coagulation pathway.

intrinsic

True or False- Tissue factor 7a begins the extrinsic coagulation pathway.

true

Which 3 factors must be activated in order to activate thrombin?

2, 5, & 10

Administration of _____ SQ is the treatment for anticoagulant rodenticide toxicity.

vitamin K

True or False- Stored, frozen plasma can be used to treat anticoagulant rodenticide toxicity.

true

In anticoagulants rodenticide toxicities, packed RBCs should only be given _____ plasma.

after

Changes in which 3 of the following describe Virchow's triad of thrombosis?

-blood flow

-endothelium

-coagulation factors

True or False- Diagnosis of pulmonary thromboembolism is easy.

false

Artificial hypercoagulability can be seen with a _____ PCV/hematocrit.

low

Artifical hypocoagulability can be seen with a ______ PCV/hematocrit.

high

Which of the following is generally used to diagnose pulmonary thromboembolism in animals?

clinical signs and predisposing factors

In addition to anti platelet and anticoagulant meds, which 2 of the following may be useful for thromboembolism?

-arginine

-magnesium

Aspirin inhibits COX enzymes, and decreases TXA2 (prothrombotic) from _______.

platelets

Aspirin _____ PGI2 (antithrombotic) from endothelial cells.

decreases

Which cells make more COX enzymes?

endothelial cells

_______ binds anti-thrombin, thrombin, and Factor 10a.

unfractionated heparin

True or False- LMWH binds both Factor 10a and thrombin.

false, only factor 10a

Which type of heparin has a longer half-life?

LMWH

______ mediates interactions between platelets, and is a pre-cursor to fibrin.

Fibrinogen

True or False- Early breakdown of fibrin clots can cause delayed bleeding.

true

Which of the following breaks up fibrinogen and fibrin?

plasmin

_______ & _______ is used as a treatment for increased fibrinolysis.

aminocaproic acid & tranexamic acid

Which breed is predisposed to VWD?

dobermans