8th lecture (embolisim, thrombus)

Question 1

what is thrombosis?

Answer 1

pathological form of homeostasis

Question 2

steps of hemostasis?

Answer 2

1. endothelial cell injury, release of substances causing vasospasms which slow down circulation.
2. adhesion of platelets to exposed area where endothelial cells are missing.
3. activation of fibrin and polymerization of fibrin
4. thrombomodulin stops coagulation cascade to form stable hemostatic plug.

Question 3

what are the virchowian trials (Rudolf virchow, famous German pathologist)

The 3 factors for thrombosus.

Answer 3

1. endothelial lesions: the hemostatic plug itself can generate thrombosus, thus anything that causes trauma to endothelium can cause thrombosus. Vasculitits can do this
2. Altered blood flow: Turbulence do to aneurysm which causes endothelial injury. stasis of the blood can also do this, since blood stasis generates hypercoagulability since coagulation factors are not being washed out with lamina blood flow, removing factors and platelets.
3. hypercoagulability: more chances to coagulate the blood, could be primary or could be secondary:
   Primary = genetics (laiden mutation to factor V, or mutation of prothrombin gene)
   Secondary = Flow?

Question 4

Morphology of a thrombosis?

Answer 4

1. White thrombus (sedimentation thrombus): endothelial injury that cause mostly platelets to coagulate.
2. Red thrombus: Coagulated blood (characteristic for venous thrombus) the blood coagulates as it is making a “cast”
3. composite thrombus: white head and red tail. this is do to the initial white thrombus forming in the artery and a stasis forms behind the thrombus causing it to propagate with a red tail.
4. Laminated thrombus: characteristic for aneurysm since in aneurysm has 2 factors, the dilation is caused by endothelial injuries (atherosclerosis, M.I.) and the other is the stasis or turbulent blood flow in an area. The blood flow can fluctuate between static or turbulent blood flow, making a layers white-red-white-red areas making LINES OF ZAHN
5. DIC: disseminated intravascular coagulation (small parts of coagulated blood floating in the blood)

Question 5

what is line of Zahn of thrombus?

Answer 5

alternating layers (laminations) of platelets mixed with fibrin, which appear lighter and darker layers of red blood cells. 
This forms a laminated thrombus that is made up of layers of white and red thrombus.

Question 6

Localization of the thrombus?

Answer 6

A/ Mural thrombus
-atrial 
-ventricular
-valves
B/ arterial thrombus
-Atherosclerosis
-Aneyrisim (exclusion from laminal flow)
-Vasculitis
C/ Venous thrombus (phlebothrombosis)
-Vena femoralis
-periprostatic
-parametric
-portal

Question 7

Describe the mural thrombus? (related to the heart)

Answer 7

Thrombus is located in the atria:
-mitral stenosis causing stasis of the blood in the atria
-arrhythmia absolute and this causes stasis of blood in atria do to the lack of contraction in the atria
-auricles of the atrial are excluded from the circulation, thus this is most typical place for atrial thrombus.
Ventricular thrombus:
-caused by the aftermath of a myocardial infraction, the paradox pulsation caused dilation of a certain area of the heart. The area becomes fibrotic and stasis of blood occurs in the area making it thrombogenic.
-Valves:
vegetation of the valve; when the valve have aggregation of platelets and RBC and endocarditis.

Question 8

Describe the arterial thrombus?

Answer 8

• atherosclerosis: since the plaque may ulcerate and forming a thrombogenic surface.
• aneyrisim: any are where the blood is excluded from laminar flow of the circulation, stasis, turbulence flow, and thrombogenic surface.
• vasculitis: inflammation of the vessels may initiate thrombus.

Question 9

describe venous thrombus (phlebothrombosis)?

Answer 9

These are usually re-thrombus, with a cast-like red coagulate. Characteristic for the vena-femoralis during long periods of inactivity of legs, do to lack of muscle pump.

• Peri-prostatic: prostate hyperplasia compresses the vein flow of the peri-prostatic veins do to stasis.
• parametric (in pregnant women) the fetus may block the parametrial venous circulation causing thrombosis
• portal vein; cirrhosis causing the blocking of the portal veni resulting in coagulation in the portal vein.

Question 10

what classes of thrombus are usually (but no always) found in what kindof vessel?

Answer 10

• Artery = white thrombus
• Veins = red thrombus
• systemic circulation = composite thrombus.

Question 11

FATE of the thrombus (what may happen to the thrombus)?

Answer 11

• propagation: thrombus may grow do to the stasis of the blood behind it
• embolism: Thrombus that partly or completely detaches
• organization: Fibroblasts may grow into the thrombus and fibrosis occurs and occlude/organize the fibrotic tissue
• recanalization: endothelial cells in-grow into the thrombus making small capillaries through the thrombus, the capillaries may fuse and make a new channel.
• thrombolysis: Thrombolytic activity dissolve the thrombus

Question 12

Describe the Clinical aspects of thrombosus?

Answer 12

A/ venous thrombus
1. superficial artery femoralis
2.deep vein femoral
3. parametric
4. periprostatic
5. vena-portae 
B/ Cardiac
1. Atraial
2. Ventricular 
3. Valvular
C/ Arterial
1. arteriosclerosis
2. aneurysm

Question 13

Describe venous thrombus clinical aspects? (5 total)

Answer 13

1. superficial artery femoralis (superficial arteries under skin which may develop thrombosis if varicosities are present since they slow down/stasis of blood occurs. (THIS is not dangerous since they cannot provide pulmonary embolism)
2. deep vein femoral (deep vein thrombosis do to inactivity) Inactivity in the legs also causes Edema since there is a lack of outflow.
3. parametric; (in pregnant women) the fetus may block the parametrial venous circulation causing thrombosis
4. periprostatic: prostate hyperplasia compresses the vein flow of the peri-prostatic veins do to stasis.
5. vena-portae: cyrosis causing the blocking of the portal veni resulting in coagulation in the portal vein.

Question 14

Describe the cardiac thrombus clinical aspects? (3 total)

Answer 14

thrombus could come from the:

• atrial (arrhythmia absolute OR mitral stenosis)
• ventricular (myocardial infraction)
• valvular: vegetation of the valve; when the valve have aggregation of platelets and RBC and endocarditis.

Question 15

Describe arterial thrombosis clinical aspects? (2 total)

Answer 15

1. atherosclerosis

2. aneurysm

Question 16

Describe DIC?

Answer 16

Disseminated intravascular coagulation is a condition in which small blood clots develop throughout the bloodstream, blocking small blood vessels

Question 17

what conditions generate the coagulation seen in DIC?

Answer 17

A/ obstetic
1. fetus mortis
2. abruptio placentae
3. amnionic fluid embolisim
4. septic abortion
B/ Infection
1. sepsis (patients in trauma unit)
2. meningococcal infection
C/ trauma
1. "car crash"
D/ burns
E/ neoplasm

Question 18

Define obstetic?

Answer 18

relating to childbirth and the processes associated with it.

Question 19

Obstetic DIC (disseminated intravascular coagulation) examples? (4 total).

Answer 19

A/ obstetic

• fetus mortis: (dead fetus in the mother, and the dissolution of the cells causes tissue factors to be squeezed into the circulation, causing coagulation)
• abruptio placentae: (placenta separation caused bleeding and tissue necrosis causing tissue factors to get into the circulation, forming the clot)
• amniotic fluid embolism (during placenta separation the amniotic fluid/cells can get into the circulation and cause coagulation via tissue factors)
• septic abortion: termination of the pregnancy may leave some fetal tissues in the uterus. This is a source for infection causes sepsis and tissue factor release.

Question 20

Infection DIC examples?

disseminated intravascular coagulation

Answer 20

B/ infection

• Bacteria is in the circulation: The bacteria release toxins and substances that activate coagulation. The infection can also damage the endothelial cells.
• meningococcal infection

Question 21

Trauma causing DIC examples? (disseminated intravascular coagulation)

Answer 21

C/ trauma

Crash syndrome; (car crash) the squeezing of the body squeezing the cells which release factors activating coagulation.

Question 22

Burns causing DIC examples? (disseminated intravascular coagulation)

Answer 22

D/ Burn

- Damage to the cells causing the tissue factors to be squeezed out into the circulation.

Question 23

Neoplasm causing DIC examples? (disseminated intravascular coagulation)

Answer 23

E/ neoplasm
certain neoplasms create pro-coagulant factors. Especially adenocarcinoma that produce mucin which has a factor for coagulation of the blood. Examples of this are: Pancreatic and stomach caner.

Question 24

what are the consequences of DIC (disseminated intravascular coagulation)

(2 total)

Answer 24

1. thrombosus/ebolisim/ischemia
   (lung is most affected as the capillaries are obliterated, Kidney failure as capillaries are obstructed, Neurological problems (brain) could also occur if capillaries in brain are clogged.
2. bleeding do to DIC using up the platelets and coagulation factors. (very dangerous).
   Consumption coagulopathy.

Question 25

Describe embolism?

Answer 25

corpuscular elements in the circulation. An obstruction of an artery, typically by a clot of blood or an air bubble

• 99% of the embolism is thromboembolism (thrombus which forms embolism having been dislodged from another site)
• 2 groups
  1. pulmonary embolism
  2. systemic embolism

Question 26

Describe pulmonary embolism?

Answer 26

• mostly coming from the deep veins of femoral or poploteal vein and goes to right atrial and ventricle and then into the lungs.
  1. total pulmonary embolisim: (completely obstructing the pulmonary vein) the venous thrombus that forms a “cast” the is like a snake that fills up the whole femoral vein. This snake-like thrombus coils up causing obstruction. Acute right sided failure occurs immediately. COR PULMONALE ACUTUM or sometimes the term: cor pulmonale acutum punctum is used indicating immediate death.
  2. Subtotal pulmonary embolism: one trunk is obstructed but the others are fine. Survival will be determined by the heart condition; if the heart can pump against the increased resistance.
  3. Partial embolism: in the lung only the small arteries are obstructed.

Question 27

Describe the systemic embolism?

Answer 27

• 2/3 of the systemic embolism comes from the heart, from the atria or the ventricle. (mitral stenosis, atrial fibrillation, myocardial infraction)
• atherosclerotic plaque or aneurysm.
• Paradox embolism: Thrombus from the venous side goes into the systemic circulation, The patient must have a shunt between the right and left side of the heart, (congenital malformation) allowing venous thrombus to pass through it.

Question 28

what are the consequences of thrombus?

Answer 28

-may get into any organ causing infraction of that organ. The clinical symptoms depend on which organ and the amount that they are effected by.
Artery occlusion results in intolerable amount of pain. If the occlusion of the organs may show no symptoms.

Question 29

Describe Fat embolism?

Answer 29

also related “crash syndrome”, If multiple bones are fractured they may release the fat in the bone marrow. The fat globules can obstruct the capillaries. But the fat droplets can also release fatty acids. Fatty acids are toxic to endothelial cells causing damage which may generate DIC.

Question 30

describe gas embolism?

Answer 30

caisson disease: Decompression sickness describes a condition arising from dissolved gases coming out of solution into bubbles inside the body on depressurisation.
the bubbles can obstruct the capillaries.
Surgery of the neck (especially on the thyroid gland) there is a negative pressure of the veins of the neck and this sucks in air.

Venous ingestion (air in the syringes)
Amniotic fluid embolism: during delivery the open veins in the uterus which could cause amniotic fluid to enter the circulation, which may cause DIC
TUMOR embolism: in advanced cancer, the cancer disrupt the venous system by ingrowing into the venous system causing embolism.