Common Vascular Events In Disease And Injury

Question 1

Hemorrhage

Answer 1

Discharge of blood from the blood vessels

Question 2

Extravasation

Answer 2

Process of discharging blood from the blood vessels into the surrounding tissues

Question 3

Splinter hemorrhage

Answer 3

Tiny blood clots that tend to run vertically under the nails

Associated with endocarditis

Question 4

Melena

Answer 4

Black stool - upper GI bleed

Question 5

Hematochezia

Answer 5

Lower GI bleed - blood in stool that is bright red

Question 6

Peripartum Hemorrhage

Answer 6

Reproductive - after giving birth

Question 7

Gross hematuria

Answer 7

Blood in urine

Question 8

Hemoparicardium

Answer 8

Bleed fills up the pericardial sac

Question 9

Hemothorax

Answer 9

Bleed in lung - fills up pleural space and may compress the lung

Question 10

Subdural hematoma

Answer 10

In brain region

Question 11

Hematoma

Answer 11

Collection of extravasated blood within the surrounding tissues or body space

Question 12

Epidural bleed - outside the dura
Subdural - below the dura
Intracerebral - inside brain tissue

Answer 12

…

Question 13

Ecchymosis

Answer 13

Hematoma associated with skin or mucous membrane that measures greater than 1cm in diameter

Question 14

The terms hematoma, ecchymosis, contusion and bruise are often used interchangeably…contusion implies trauma - whereas the other terms may or may not be the cause

Answer 14

…

Question 15

Exsanguination

Answer 15

“Bleed to death,” fatal loss of blood from massive hemorrhage

Question 16

Exsanguination may be used medically with…

Answer 16

May be used in surgery in a localized sense, when using a tourniquet and temporarily draining blood from a region - “bloodless surgical field”

Question 17

Hemostasis

Answer 17

Normal and tightly regulated process that maintains blood in a fluid state when appropriate and aims to arrest bleeding in the event of traumatic vessel damage

Question 18

In the event of traumatic vessel damage, set of regulated steps aims to arrest bleeding, beginning with….

Answer 18

Arteriolar vasoconstriction

Question 19

The trio in hemostasis?

Answer 19

Vasculature and hydrodynamics of blood flow:

• endothelium
• smooth muscle
• basement membrane

Platelets:

• receptors for binding, aggregation, activation
• phospholipid surface

Coagulation cascade:
-proteins with enzymatic activity leading to fibrin mesh work

Question 20

Vessel spasm

Answer 20

First response in tissue injury to blood vessel

Reduces the flow of blood from the vessel rupture

Booth local nervous reflexes and humoral factors released from plates (thromboxane) contribute to vasoconstriction

Question 21

The endothelium normally secretes prostaglandins and nitric oxide to promote vasodilation and keep platelets away. Disruption exposes collagen and releases..

Answer 21

Von Willebrand factor!! (VWF) - triggers platelet adhesion and activation)

Question 22

Von willebrand factor is released from the endothelium and binds to platelet receptors causing adhesion of the platelets to exposed collagen fibers. As the platelets adhere to the collagen fibers on the damaged vessel wall, they become activated and release ADP and TXA2. The ADP and TXA2 attract additional platelets, leading to platelet aggregation.

Answer 22

…

Question 23

Activated platelets send out processes that help them enmesh.

Answer 23

…

Question 24

What is the goal of the coagulation cascade?

Answer 24

Create fibrin glue to support plug until endothelium and extracellular matrix remodel

Question 25

Two coagulation pathways

Answer 25

1) intrinsic - begins in the circulation and is initiated by activation of circulating factor XII 2) extrinsic - activated by cellular lipoprotein tissue factor that becomes exposed when tissues are injured. Both pathways lead to the activation of factor X, conversion of prothrombin to thrombin, and conversion of fibrinogen to fibrin threads that hold the clot together

Question 26

Fibronigen to fibrin is catalyze by what?

Answer 26

Thrombin

Question 27

Activated platelet surface provides phospholipids needed to trigger the coagulation cascade

Answer 27

...

Question 28

Primary hemostasis

Answer 28

Platelets release thromboxane - activates and recruits more platelets and they aggregate

Question 29

Secondary hemostasis

Answer 29

Fibrin deposited now

Question 30

Thrombus and antithrombotic events (after primary and secondary hemostasis)

Answer 30

Release of TPA (fibrolysis) and thrombomodulin (blocks coagulation cascade)

Question 31

Flipping of phosphatidylserine from inner to outer membrane surface... exposure on platelets results from damage or from platelet damage itself

Answer 31

...

Question 32

Plasmin, antithrombin, and proteins C and S... involved in localization of hemostasis...?

Answer 32

...

Question 33

Hemostasis is problematic when it leads to the complete obstruction of key blood vessels..also known as thrombotic occlusion

Answer 33

...

Question 34

Thrombus

Answer 34

Clot adherent to vascular endothelium

Question 35

Two worst places for thrombus - coronary (HA) or cerebrovascular places (Strokes)

Answer 35

...

Question 36

A group of three underlying conditions increases the risk of thrombosis. That group is... and is called...

Answer 36

Virchow's triad Relates to: 1) endothelium (injury) 2) blood flow (stasis or turbulence) 3) coagulation pathway (hypercoagulability state) Ex. Atrial fibrillation - turbulent Paralysis - embed blood flow Protein C or S deficiencies lead to clot formation

Question 37

Blood flow abonormalities

Answer 37

Atrial fibrillation Bed rest, paralysis Venous obstruction

Question 38

Contact surface abnormalities

Answer 38

Atherosclerosis Vascular injury/trauma Abnormal heart valve Indewelling vascular catheter

Question 39

Clotting component abnormalities

Answer 39

``` Elevated factor VIII Factor V Leiden Prothrombin 20210 Protein C/S deficiency Antithrombin deficiency Estrogen therapy/pregnancy Malignancy ```

Question 40

Thrombus formation is one mechanism of creating an obstruction that narrows or occludes blood flow. Another mechanism is through disordered vessel development, such as...

Answer 40

Congenital stenosis or atresia

Question 41

Atresia

Answer 41

Not properly formed valve

Question 42

Stenosis

Answer 42

Narrowing of valves/vessels

Question 43

Another mechanism of obstruction to blood flow is compression from an enlarging newborn gene structure called....

Answer 43

Mass effect Ex. Gravid uterus Neoplasm Pregnancy

Question 44

Another mechanism for obstruction of blood flow is torsion...

Answer 44

Testicular torsion ex. Twisting of the spermatic cord cuts off venous drainage of the testis... Bowel volvulus has a similar torsion mechanisms

Question 45

Another mechanism of obstruction to blood flow is pressure from edema... called....

Answer 45

Compartment syndrome Blood flow to distal limb is compromised due to compression from surrounding swollen tissue

Question 46

Another mechanism of obstruction to blood flow is atherosclerosis....

Answer 46

The resultant atheromas (also called atheromatous plaques) cause protrusions into vessel lumens, narrowing them

Question 47

Ischemia

Answer 47

Hypoxia (low o2) due to reduced blood flow

Question 48

Infarct

Answer 48

Area of ischemic necrosis caused by occlusion of arterial supply (or venous damage)

Question 49

Most infarcts are from...

Answer 49

Thrombotic or emboli arterial occlusion

Question 50

Venous infarcts are far less common than arterial infarcts... Arteries have tissue turn white Veins have tissues turn red (Cant drain blood)

Answer 50

...

Question 51

Embolus

Answer 51

Detached mass (solid, liquid, or gas) carried by blood to a site distant from its point of origin... Most common type are thromboemoli... Among other types are fat, marrow, air, tumor, amniotic fluid

Question 52

Only few places in the body where you have a collateral supply so generally emboli can be a problem anywhere in the body

Answer 52

...

Question 53

Shock

Answer 53

Global underperfusion of tissues resulting in cellular hypoxia (commonly associated with systemic hypotension)

Question 54

3 main types of shock 2 minor

Answer 54

Cardiogenic, hypovolemic, septic Neurogenic, anaphylactic

Question 55

Both septic and anaphylactic shock involve the immune system...

Answer 55

...

Question 56

Cardiogenic shock

Answer 56

Pump failure (heart)

Question 57

Hypovolemic shock

Answer 57

Massive fluid loss, fluid loss from sever burns

Question 58

Septic shock

Answer 58

Systemic immune rxn to infection, get vasodilation and peripheral blood pooling

Question 59

Cardiogenic shock can occur days after HA

Answer 59

...

Question 60

Hyperemia

Answer 60

Locally increased blood flow from the active process of arteriolar dilation (ex. Muscle exercising)

Question 61

Congestion

Answer 61

Blood stasis from reduced outflow from tissue = passive process (ex. Venous obstruction)

Question 62

Edema

Answer 62

Abnormal increase of interstitial fluid within tissues

Question 63

Causes of edema

Answer 63

- reduced plasma oncotic pressure (reduced albumin in liver failure) - lymphatic obstruction (e.g. Filarial worms = elephantiasis) - increased hydrostatic pressure (e.g. Increased venous pressure of congestive heart failure)

Question 64

There are specialized names for hemorrhages of skin ("rash") and mucous membranes ("enanthem") Exs. Petechiae, purpura, ecchymosis (all for skin, and increase in size)

Answer 64

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Question 65

Petechiae come from viral infection. Purpura comes from bacterial infection... generally

Answer 65

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