Midterm I Flashcards Preview

Veterinary Pathology I > Midterm I > Flashcards

Flashcards in Midterm I Deck (115)
Loading flashcards...
1

What is the fundamental cause of necrotic cell death?

Depletion of ATP below 10%

2

What are the ways in which cells can be injured?

1. Mitochondrial damage
2. Depletion of ATP
3. Influx of Ca+ and loss of Ca+ hemostasis
4.Accumulation of free radicals
5. Defects in membrane permeability
6. Damage to DNA and proteins

3

What are the characteristics of irreversible cell injury?

1. Inability to reverse mitochondrial dysfunction
2. Profound damage to membrane function

4

What are coagulation factors, where do they come from and what is their purpose?

Plasma proteins made by the liver which function to form fibrin

5

Hemostasis

The arrest of bleeding; mechanism to stop bleeding when a vessel is damaged

6

What does PT measure?

Stands for prothrombin time and measures the extrinsic and common coagulation pathway with fibrin being most important part of clot formation

7

What does PTT measure?

Stands for partial prothromboplastin time and measures the intrinsic and common coagulation pathway with results indicating there is a deficiency of a coagulation factor like in hemophila

8

Which coagulation factors are part of the extrinsic pathway and how is it activated?

7 and Tissue factor
Endothelial injury and release of TF

9

Which coagulation factors are part of the intrinsic pathway and how is it activated?

12, 11, 9, and 8
Platelets contacting the basement membran..aka collagen..during vasoconstriction

10

What are D-Dimers and what does this measurement tell us?

Cross-linked polymers produced as a result of accelerated hemostasis and breakdown of fibrin in a clot. If too high, indicate that there are too many clots being produced in body aka disseminated intravascular coagulation

11

What does prothrombin do and which coagulation pathway is it part of?

It activated thrombin within the common coagulation pathway..activated by factor 10

12

How is fibrin in a clot created?

Factor 10 stimulates prothrombin to activate thrombin which activated fibrinogen to make fibrin

13

What substance breaks down fibrin in a clot? How is it activated?

Plasmin
Plasminogen activated plasmin

14

What is disseminated intravascular coagulation?

A condition in which abnormal clots form inside vessels using up clotting factor which makes them unavailable in a part of the body that needs a clot to stop bleeding. Leads to clots everywhere and massive bleeding. Has many causes.

15

What is the buccal mucosal bleeding time and what do results tell us?

It is a measure of primary hemostasis and defeciency in von Willebrand factor. If this is normal, it means platelets are functioning normally with adequate von Willebrand's factor needed for platelet plug to stick to wall

16

How do you perform a BMCT test?

1. Lateral recumbency and lift upper lip with a gauze muzzle
2. Using a lancet choose area free of blood vessels
3. Depress into mucosa and remove
4. Allow blood to bleed onto filter paper until it stops, count time..don't directly touch incision.
5. Make sure dog can't taste blood and try to lick
6. Normal is 1.5 to 4 min for dogs and 1.5 to 2.5 for cats

17

What is phytonadione and why would it be given if you suspect there is an issue with coagulation factors?

Vitamin K
It is needed to produce the factors involved in the intrinsic, extrinsic, and common coagulation pathways...2, 7, 9, 10. (I'm 27 and will die when i am 90)

18

If the animal was deficient in vitamin K, which tests would be affected?

PT and PTT

19

What three factors work together during hemostasis?

1. The vessel wall with endothelial cells
2. Platelets
3. Coagulation System

20

What are some important antithrombotic mediators?

1. Prostacyclin (PGI2)
2. Nitric Oxide (NO)
3. Heparin like molecules
4. Thrombomodulin
5. Tissue plasminogen activator (t-PA)

21

What are some important prothrombotic mediators?

1. Von Willebrand's factor
2. Tissue Factor
3. Plasminogen activator inhibitor-1

22

Which two mediators in hemostasis do you want to be present at all times? Why?

1. Tissue plasminogen activator (t-PA): promotes fibrinolysis which breaks down fibrin, helps to accerlate the breakdown of clots
2. Plasminogen activator inhibitor-1 (PAI-1): inhibits t-PA therby preventing fibrinolysis

23

What are the three reactions platelets go through during hemostasis?

1. Adhesion and shape change
2. Secretion
3. Aggregation

24

What do platelets secrete after they have attached to the collagen of the subepithelium and sent pseudopods across the defect forming a plug?

1. ADP: mediator of platelet aggregation
2. Thromboxane A2: platelet aggregator and vasoconstrictor
3. Fibrinogen: glue that sticks platelets together

25

Which part of hemostasis is reversible?

Primary

26

What is the term for when there are reduced platelets causing spontaneous bleeding throughout body ( but below 20,000 per L)

Thrombocytopenia

27

According to new research is it believe that __________ pathway of coagulation starts first and the __________ pathway amplyfies the reaction.

Extrinsic
Instrinsic

28

Which are coagulation factors affected by Vitamin K antagonists like warfarin?

2 (prothrombin), 7, 9 and 10

29

How does the coagulation cascade remain localized?

Antithrombin factors like Antithrombin III, protein C and S, and plasmin

30

Which measurement a is mainly concerned with primary hemostasis? Secondary?`

Buccal mucosal Bleeding time
PT and PTT