11. Heme Disorders 2

Question 1

Most important coagulation factor.

Answer 1

Thrombin

Question 2

Component of the coagulation cascade that links the fibrin monomers that make up a clot.

Answer 2

Factor XII (Hageman Factor)

Question 3

What does the Prothrombin Time (PT) assay assess?

Answer 3

The function of proteins in the extrinsic pathway of the coagulation cascade.
Factors: II, V, VII, X

Question 4

How is a PT assay performed?

Answer 4

Calcium is administered to coagulation proteins and then the time for a clot to form is measured.

Question 5

What does the Partial Thromboplastin Time (PTT) assay assess?

Answer 5

The function of protein in the instrisic pathway of the coagulation cascade.
Factors: II, V, VIII, IX, X, XI, XII

Question 6

How is a PTT assay performed?

Answer 6

Ground glass is administered to coagulation proteins and its (-) charge activates Factor XII. Then time it takes to form a clot is then recorded.

Question 7

Name the 3 categories of endogenous anticoagulants.

Answer 7

1. Antithrombins (antithrombin III)
2. Protein C and S (vitamin K-dependent)
3. TFPI - inactivates tissue factor VIIa

Question 8

3 abnormalities that lead to thrombus formation. (Virchow’s Triad)

Answer 8

1. Endothelial Injury
2. Stasis or turbulent blood flow
3. Hypercoagulability of Blood

Question 9

Major contributor to venous thrombi.

Answer 9

Stasis of blood flow

Question 10

How do stasis and turbulent flow both contribute to thrombus formation?

Answer 10

Normal laminar flow keeps clotting factors and platelets in the center of the lumen of vessels. Stasis and turbulent flow cause margination of both component which interact with the endothelium causing a thrombus to form.

Question 11

Alterations in the coagulation pathway that leads to hypercoagulability. Genetic Cause?

Answer 11

1. Thrombophilia

2. Point mutation in Factor V gene

Question 12

Condition in which the body produces antibodies to heparin and platelet levels drop because of the many thrombi that start to form.

Answer 12

Heparin-Induced Thrombocytopenia (HIT)

Question 13

Condition with recurrent thrombus formation, repeated miscarriages, and cardiac vegetations due to auto-antibodies formed against endothelial phospholipids.

Answer 13

Antiphospholipid Antibody Syndrome (Lupus Anticoagulant syndrome)

Question 14

Thrombus that grows retrograde from blood flow and forms at sites of turbulence.

Answer 14

Arterial Thrombi

Question 15

Thrombus that extends in the direction of blood flow and occurs at sites of blood stasis.

Answer 15

Venous Thrombi

Question 16

Platelet and Fibrin deposits located on vascular endothelium that indicate a thrombus formed ante-mortem (before death)

Answer 16

Lines of Zahn

Question 17

Thrombi occurring in the heart chamber or aortic lumen.

Answer 17

Mural Thrombi

Question 18

Frequently occlusive thrombus that is often superimposed on an atherosclerotic plaque.

Answer 18

Arterial Thrombus

Question 19

Thrombus that is invariably occlusive that often forms in the lower extremities.

Answer 19

Venous Thrombus

Question 20

Thrombi that form on heart valves usually as a result of blood-bourne bacteria or fungus.

Answer 20

Vegetations

Question 21

Non-bacterial endocarditis often seen in SLE.

Answer 21

Libman-Sacks endocarditis

Question 22

4 events a thrombus can go through in the days after its initial formation.

Answer 22

1. Propagation - accumulation of platelets and fibrin
2. Embolization - detachment
3. Dissolution - fibrinolysis
4. Organization and Recanalization

Question 23

How does widespread microvascular thromboses lead to bleeding disorders?

Answer 23

The many microvascular thromboses cause platelet aggregation and usage of the coagulation factors. This depletes the body’s store of these components and then when fibrinolysis occurs there is excessive bleeding b/c no platelets or coagulation factors can stop it.

Question 24

Detached intravascular solid, liquid, or gas.

Answer 24

Embolism

Question 25

Where do most pulmonary emboli come from?

Answer 25

DVT in the lower extremities, usually above the knee.

Question 26

Type of pulmonary embolism that can easily become lodged and cause sudden death.

Answer 26

Saddle embolism.

Question 27

Name 3 causes of emboli.

Answer 27

1. Hypercoagulability 2. Immobilized pts. 3. Heart Failure

Question 28

Diagnostic characteristic on physical exam that a patient has a pulmonary embolism.

Answer 28

Absence of a pulse but a normal rhythm is seen on EKG.

Question 29

Diagnostic of a pulmonary embolism on chest X-ray.

Answer 29

Hampton's Hump

Question 30

Major cause of fat emboli.

Answer 30

Broken long bones. (The fat in the bone marrow is released into circulation)

Question 31

2 common clinical manisfestations of air emboli in scuba divers.

Answer 31

1. The Bends - air emboli in skeletal muscle | 2. The chokes - gas bubbles in vasculature

Question 32

Chronic form of decompression sickness.

Answer 32

Caisson's Disease

Question 33

Cross contamination of mother's blood with amniotic fluid causing an allergic reaction and possilbe death of the mother.

Answer 33

Amniotic Fluid Embolism

Question 34

Classic findings in an amniotic fluid embolism.

Answer 34

Sqamous cells shed from fetal skin. (looks like a finger-print on histology slides)

Question 35

Major clinical finding of shock.

Answer 35

Systemic Hypotension

Question 36

How does the patient present with hypovolemic or cardiogenic shock?

Answer 36

Cool, clammy, cyanotic skin. | Weak rapid pulse, tachypnea

Question 37

How does a patient present with septic shock?

Answer 37

Warm flushed skin usually due to peripheral vasodilation.