Morphology of Hemodynamic Disorders

Question 1

What are the two categories that make up simple changes in blood flow

Answer 1

Hyperemia
Congestion

Question 2

What is hyperemia

Answer 2

Increased blood flow due to arteriolar dilation

Question 3

How can tissue affected by hyperemia be described

Answer 3

erythemic (red)

Question 4

What is congestion

Answer 4

Reduced venous outflow
Can be systemic or local

Question 5

How can tissue affected by congestion be described

Answer 5

Cyanotic

Question 6

Congestion and hyperemia - which is active v passive

Answer 6

Congestion - passive
Hyperemia - active

Question 7

Hemorrhage:

Answer 7

Extravasation of blood into tissues, body cavities, or externally

Question 8

What are some general causes of hemorrhage (think categories)

Answer 8

Trauma
Vit K deficiency
Vasculitis
Aneurism rupture
Heriditary

Question 9

How can hemorrhage be heriditary

Answer 9

Genetic coag factor defect
Platelet function is altered

Question 10

Purpura:

Answer 10

purplish or brownish-red discoloration of the epidermis due to hemorrhage

Question 11

Petechia

Answer 11

Pinpoint hemorrhage, smallest lesion that is grossly visible

Question 12

Ecchymosis:

Answer 12

Larger (>1cm) focus of hemorrhage

Question 13

Description of hemorrhage into body cavities -

Answer 13

hemo- + cavity
ex: hemothorax, hemopericardium, etc

Question 14

Hematoma:

Answer 14

localized collection of clotted blood found in tissue space
(extravascular coagulation)

Question 15

Thrombosis:

Answer 15

Pathologic presentation of normal hemostatic pathways
Occurs within intact blood vessels
Needs to be distinguished from a post-mortem clot at necropsy

Question 16

Hemoptysis:

Answer 16

Blood or blood-stained sputum
Ew.

Question 17

Hematochezia:

Answer 17

fresh blood in feces
Usually indicates bleed in lower GI - blood was not exposed to stomach acid

Question 18

Melena:

Answer 18

Black tarry blood in feces

Question 19

What % of their blood can healthy animals stand to loose

Answer 19

20%

Question 20

What is the name for the unholy thrombotic trinity

Answer 20

Virchow’s Triad

Question 21

What are the components of Virchow’s Triad

Answer 21

Hypercoagulability (blood composition)
Stasis (flow)
Vessel wall injury (vasculature)

Question 22

How does endothelial injury contribute to thrombosis

Answer 22

Damage alters blood flow and can lead to coagulation

Question 23

How does alteration in blood flow lead to thrombosis

Answer 23

Stasis brings platelets into contact with the endothelium –> activation
Turbulence causes damage

Question 24

How does a change in blood composition lead to thrombosis

Answer 24

Increased # of platelets –> hypercoagulability
Elevated fibrin levels
Decreased anti-thrombin levels

Question 25

Post-mortem clot morphology

Answer 25

Easily removed Cast of vessel Dark red, gelatinous Shiny, smooth Area of yellow if RBCs settle out

Question 26

Arterial thrombi morphology

Answer 26

Form in areas of rapid blood flow Attached to sites of endothelial damage Retrograde growth Pale/grey Dry, friable Alternating layers of fibrin and platelets

Question 27

Venous thrombi morphology

Answer 27

Areas of slow flow Attached to area of injury Grow in direction of blood flow Form in casts BUT not easy to remove Firm, moist, red

Question 28

What are the possible 'fates of thrombi

Answer 28

Propagation Dissolution Embolization Organization Recanalization

Question 29

Propagation:

Answer 29

continues to grow

Question 30

Dissolution:

Answer 30

Clot dissolved by fibrinolysis

Question 31

Embolization:

Answer 31

Dislodges and travels somewhere else (thromboembolism)

Question 32

Organization:

Answer 32

conversion to fibrous connective tissue

Question 33

Recanalization:

Answer 33

small vessels form in the thrombis to re-establish blood flow

Question 34

Infarction:

Answer 34

Occlusion due to thrombis and thromboembolism

Question 35

Ischemia:

Answer 35

Hypoxia due to loss of blood supply

Question 36

Morphology of infarcts

Answer 36

Wedge shaped, poorly defined when fresh

Question 37

White infarct morphology

Answer 37

Arterial occlusion in solid tissues/organs

Question 38

red infarct morphology

Answer 38

Can be venous or arterial Venous - loosely organized tissue (lungs) Arterial - in tissues with secondary collateral blood supply, may have originally been white

Question 39

WHat do bland vs septic infarct refer to

Answer 39

etiology

Question 40

Bland infarct:

Answer 40

Sterile, most common

Question 41

Septic infarct:

Answer 41

Contaminated with bacteria, can produce an abscess