Hemostasis

Question 1

platelets life cycle lasts ____ days

Answer 1

5-10 days

Question 2

how long does it take to form a platelet plug?

Answer 2

5 min

Question 3

platelets are attracted to exposure of collagen (which happens with any disruption of vascular endothelium) and undergo 3 reactions:

1. ___
2. ___
3. ___

Answer 3

1. adhesion and shape change
2. secretion
3. aggregation

Question 4

exposure of subendothelium and platelet adhesion depends on ______

Answer 4

von Willebrand factor

Question 5

Platelet type bleeding CS:

Answer 5

-petchiae, ecchymoses, or mm bleeding

Question 6

____ and ____ are the key tests in assessment of primary hemostasis

Answer 6

platelet count and bleeding time

Question 7

dogs and cats with normal platelet function usually do not have spontaneous bleeding until the number of platelets is below what?

Answer 7

30,000

Question 8

normal buccal mucosal bleeding time

Answer 8

less than 4 min (measure the time until the bleeding completely stops)

Question 9

ACT (activating clotting time) evaluates which pathway?

Answer 9

intrinsic and common

Question 10

PTT (activated partial thromboplastin time) evaluates which pathway?

Answer 10

intrinsic and common

Question 11

PT (prothrombin time) evaluates which pathway?

Answer 11

extrinsic and common

Question 12

What does ACT measure?

Answer 12

• measures the time required for fibrin clot formation in fresh whole blood
• activates clotting cascade allowing assessment of the integrity of both intrinsic and common pathways
• ACT is prolonged if any of the factors involved drop to less than 25% of normal concentration

Question 13

What is a normal ACT result?

Answer 13

60-90 seconds

Question 14

What does PT measure?

Answer 14

checks function of factors X, V, II, and I of the common pathway, and factor VII of the extrinsic pathway

Question 15

How to treat von Willebrand’s disease?

Answer 15

give DDAVP 1 microgram/kg. give 30 min before induction and recheck buccal mucosal bleeding time before sx.

Question 16

Hemophilia A is what?

Answer 16

An X linked factor deficiency of factor VIII (ACT and PTT will be elevated)

Question 17

Hemophilia B is what?

Answer 17

An X linked factor deficiency of factor IX (ACT and PTT will be elevated)

Question 18

Which factors are affected with rodenticide toxicity?

Answer 18

factors II, VII, IX, X are affected

Question 19

Which tests will be abnormal/elevated with rodenticide toxicity?

Answer 19

PT and PTT will be elevated

Question 20

Tx of rodenticide toxicity?

Answer 20

Vitamin K1 for 4 weeks

Recheck clotting times after finishing therapy to ensure rodenticide is completely eliminated

Question 21

Common pathway - which factors?

Answer 21

I, II, V, X

251=10

Question 22

Intrinsic pathway - which factors?

Answer 22

VIII, IX, XI, XII

I shop at wal mart because everything is under $12 (It’s always $11.98)