Clotting Disorders VTE

Question 1

What is hemostasis

Answer 1

Process to stop bleeding at the site of vascualr injery through complex interactions between vascular endothelium, platelets, procoagulant proteins, anticoagulant proteins and fibrinolytic proteins

Question 2

What are the three key mechanisms that facilitate hemostasis

Answer 2

Vascular constriction, primary platelet plug formation (primary hemostasis), clot propagation through fibrin formation (secondary hemostasis)

Question 3

What is the basic four step mechanism for platelet aggregation when injury occurs

Answer 3

Platelets first adhere to macro molecules in the sub-endothelial regions of the injured blood vessel, platelets activate, adherent platelents release substances that activate nearby platelets and recruit them, activated platelets then aggregate to form the primary hemostatic plug

Question 4

What protein initiates the coagulation system when exposed due to vessel wall injury

Answer 4

Tissue factor

Question 5

Which thrombin factor is usually seen in this coagulation, what does it do

Answer 5

Thrombin (factor IIa), thrombin converts fibrinogen to fibrin reinforcing the platelet aggregation and anchors it to the vessel wall

Question 6

T/F:The extrinsic and intrinsic pathway both convert into the common pathway for coagulation leading to more thrombin

Answer 6

True

Question 7

What are the natural inhibitors of the coagulation cascade

Answer 7

Antithrombin III, Protein C, Protein S

Question 8

What is the most common defect in the natural coagulant system, what occurs

Answer 8

Factor V leiden, mutation in factor V that results in resitance to inactivation by protein C and protein S

Question 9

What is thrombosis

Answer 9

Formation of an inappropriate fibrin-platelet aggregate

Question 10

Where are sites thrombosis can take place

Answer 10

Endothelium of blood or lymphatic vessels (mural thrombus) , within the heart (cardiac thrombus), free in blood or lymphatic vessels (thromboembolus)

Question 11

What is venous thromboembolism, what are two types

Answer 11

Clot formation within the venous circulation, DVT and pulmonary embolism

Question 12

Where do most DVTs take place

Answer 12

The proximal veins (Deep femoral vein and superficial femoral vein)

Question 13

What is the order of pulmonary embolism types from most dangerous to least dangerous

Answer 13

Saddle embolism, lobar embolism, segmental, subsegmental

Question 14

What guide is used to assess risk for ischemic stroke, what are its parameters

Answer 14

CHADS2/ Congestive heart Failure, Hypertension, Age greater than 75, Diabetes, Stroke or Trans ischemic attack

Question 15

T/F: On the CHADS2 score each category is worth one point

Answer 15

False: On the CHADS2 score each category is worth one point except Stroke or TIA, which is worth 2 points

Question 16

What are the three big risk factors for VTE, what are the collectively called

Answer 16

Blood Stasis, Hypercoagulable State, Vascular Injury/ Virchow’s triad

Question 17

What are the other risk factors for VTE

Answer 17

Age greater than 40 years, Surgery, Major trauma or lower-extremity injury, Cancer, Pregnancy

Question 18

What medication class can increase risk of blood clots

Answer 18

Estrtogens

Question 19

What are situations that could lead to blood stasis

Answer 19

Damage to venous valves, periods of proplong immobility, abnormalities of blood flow

Question 20

What disease can cause a hypercoaguable state, other factors

Answer 20

Cancer Malignancy, female gender, being black, older age (greater than 40), pregnancy

Question 21

T/F: Smoking increase risk of VTE

Answer 21

True

Question 22

What are examples of or may cause vascular injury

Answer 22

Trauma, Surgery, Heart valve replacement, Artherosclerosis or Artheromatous plaque, indwelling vascular catheters

Question 23

What orthopedic surgery has the highest risk for VTE

Answer 23

Total hip arthroplasty and Hip fracture surgery

Question 24

In hospitalized medical patients what gives the most points on Padua Prediction Risk Assesment Model

Answer 24

Active Cancer, Previous VTE, Reduced moblility, Already known thrombophilic condition`

Question 25

What are common signs and symptoms of DVT

Answer 25

Swelling, redness, tenderness, edema, palpable cord, post-thrombotic syndrome

Question 26

What are common signs and symptoms of pulmonary embolism

Answer 26

Chest pain, cough with blood, tachycardia, palpations, low grade fever, patient passes out

Question 27

What is used to diagnosis if patient as VTE, why is it not always reliable

Answer 27

D-Dimer/ elevations can occur due to recent surgeries, increasing age, pregnancy and cancer

Question 28

What risk assesment scale is used to see if a DVT is present

Answer 28

Wells pretest/ Tenderness along entire deep vein system, Swelling of the entire leg, greater than 3 cm in calf circumference, pitting edema, collateral superficial veins, active cancer, prolonged immobility or paralysis, recent surgery

Question 29

What does the Wells score need to be in order for DVT to be likely

Answer 29

Greater or equal to 2

Question 30

What is the first choice for diagnostic imaging for PE

Answer 30

CT pulmonary angiography

Question 31

When using the Wells score for pulmonary embolism put the criteria in order from the highest scores to lowest scores

Answer 31

Signs or DVT, Alternative diagnosis to PE less likely ( 3 points)/ History of PE or DVT, heart rate greater than 100 beats/min, recent surgery or immobility (1.5 points)/ Active malignancy and hemoptysis (1 point)

Question 32

What must the Wells score for PE be for it to be most likely present

Answer 32

Greater than 4

Question 33

T/F: If the D- dimer is negative PE and DVT is ruled out

Answer 33

True

Question 34

What is post-thrombotic syndrome

Answer 34

Chronic venous insuffciency as a consequence of valvular incompetence and venous hypertension due to thrombotic obstruction, usually occurs following DVT

Question 35

T/F: Initial VTE treatment should include a rapid-acting anticoagulant

Answer 35

True

Question 36

What is the usual dose to start a patient on for warfarin

Answer 36

5 mg

Question 37

What is used to monitor heparin, when is it checked

Answer 37

aPTT, every 6 hours

Question 38

What syntheizes the major clotting factors, what are three types of factors,

Answer 38

Liver/ contact activation factor, vitamin K factor, thrombin-sensitive factor