Venous Thromboembolism (VTE)

Question 1

blood clot attached to a vessel wall that is composed of platelets, fibrin, and clotting factors, may partially or completely block the lumen of a blood vessel and compromise blood flow/oxygen delivery to tissues

Answer 1

thrombus

Question 2

thrombus/blood clot causing obstruction of a deep vein in the leg, pelvis, abdomen

Answer 2

deep vein thrombosis (DVT)

Question 3

thrombus causing blockage of a pulmonary artery or branches that results in pulmonary infarction (part of the lung tissue dies because of this)

Answer 3

pulmonary embolism (PE)

Question 4

what clotting factors does warfarin inhibit?

Answer 4

II, VII, IX, X

Question 5

drugs that are factor Xa direct inhibitors

Answer 5

rivaroxaban, apixaban

Question 6

drug that is a direct thrombin (factor IIa) inhibitor

Answer 6

dabigatran

Question 7

this type of heparin inhibits factors Xa and IIa equally through antithrombin

Answer 7

unfractionated heparin (UFH)

Question 8

this type of heparin inhibits factor Xa more than IIa through antithrombin

Answer 8

low molecular weight heparins (LMWHs, enoxaparin)

Question 9

age (risk doubles with each decade after 50), history of VTE, venous stasis, vascular injury, hypercoagulable states, drug therapy (estrogen containing OC, estrogen replacement therapy, SERMs, heparin, chemotherapy)

Answer 9

risk factors for developing VTE

Question 10

prothrombin gene mutation, protein C deficiency, protein S deficiency, antithrombin deficiency, factor VIII excess, factor XI excess, antiphospholipid antibodies, dysfibrinogenemia, plasminogen activator 1 excess

Answer 10

genetic defects that increase risk of developing VTE

Question 11

risk factors that are present within the 3 months before VTE diagnosis, surgery with general anesthesia for greater than 30 minutes, confinement to bed in hospital for at least 3 days with acute illness, C section, major trauma

Answer 11

major transient risk factors of VTE

Question 12

risk factors that are present within the 2 months before VTE diagnosis, surgery with general anesthesia for less than 30 minutes, admission to hospital for less than 3 days with acute illness, estrogen therapy, pregnancy, confinement to bed out of hospital for at least 3 days with acute illness, leg injury associated with reduced mobility for at least 3 days, prolonged car or air travel

Answer 12

minor transient risk factors of VTE

Question 13

active cancer, antiphospholipid syndrome

Answer 13

persistent risk factors of VTE

Question 14

Unilateral (one side) leg pain on the affected leg, swelling after night’s sleep, cyanosis of the skin in affected leg, post-thrombotic syndrome (PTS) – long term complication of DVT caused by damage to venous valves which produces chronic lower extremity swelling, pain, tenderness, skin discoloration/ulceration

Answer 14

signs and symptoms of DVT

Question 15

nonspecific signs and symptoms similar to DVT

Answer 15

signs and symptoms of PE

Question 16

test that can confirm if a patient does not have DVT, measures fibrin breakdown in the serum and is a marker of acute thrombotic activity, not specific markers for VTE, but a negative test can be used to rule out DVT diagnosis.

Answer 16

D-dimer tests

Question 17

a Padua score of _____ or more indicates high risk of VTE and is used for _____________ patients

Answer 17

4, hospitalized medical

Question 18

a Caprini score of _____ or more indicates high risk of VTE and is used for __________ patients

Answer 18

5, general surgical

Question 19

walking, graduated compression stockings, intermittent pneumatic compression devices, inferior vena cava filters

Answer 19

non-pharmacologic measures recommended for prevention of VTE

Question 20

duration of VTE prophylaxis for patients who have undergone a knee/hip surgery

Answer 20

minimum of 10-14 days but extending to 35 days is recommended because of continued risk up to 1 month post-surgery

Question 21

prevent extension of the clot, embolization, hemodynamic collapse, death

Answer 21

short term treatment goals of VTE

Question 22

prevent post-thrombotic syndrome, pulmonary hypertension, recurrent VTE

Answer 22

long term treatment goals of VTE

Question 23

decrease short-term pain and swelling and prevent destruction of venous valves, these drugs can be used for patients with pulmonary embolism with shock, hypotension, or massive DVT with limb gangrene, controversial because compared with anticoagulants they restore venous potency more quickly, but the bleeding risk is higher

Answer 23

thrombolytics (alteplase)

Question 24

alteplase dosing for treatment of VTE, when/what type of anticoagulation should be started following treatment with a thrombolytic like alteplase?

Answer 24

100 mg infused over 2 hours, near the end or immediately following alteplase infusion a parenteral anticoagulant should be started

Question 25

these drugs will not dissolve a formed clot like thrombolytics but they prevent the clot’s propagation and growth

Answer 25

anticoagulants

Question 26

what should be monitored for to detect heparin induced thrombocytopenia (HIT)? how frequent? when to suspect HIT? management of HIT?

Answer 26

platelet counts at baseline and every 2-3 days throughout course of UFH therapy, HIT can be suspected if platelet count drops by more than 50% from baseline or below 150 or if thrombosis occurs even with UFH use, immediate discontinuation of all heparin containing products necessary and alternative parenteral anticoagulant started

Question 27

general recommended treatment for VTE

Answer 27

apixaban, dabigatran, rivaroxaban over warfarin

Question 28

recommendation for cancer-associated VTE

Answer 28

oral factor Xa inhibitor (apixaban, rivaroxaban)

Question 29

recommendation for cancer-associated VTE with GI malignancy?

Answer 29

edoxaban and rivaroxaban had higher risk of GI major bleeding, apixaban did not so apixaban or LMWH are preferred

Question 30

recommendation for VTE in patients with antiphospholipid syndrome

Answer 30

adjusted dose vitamin K antagonist (warfarin) with target INR of 2.5 rather than DOAC therapy

Question 31

initial anticoagulants following VTE diagnosis, parenteral or high dose oral anticoagulation lasting 5-21 days depending on anticoagulant regimen

Answer 31

initiation phase

Question 32

period after initiation following which treatment is completed for acute VTE event, anticoagulants used at standard therapeutic doses and is considered complete after 12 weeks/3 months of anticoagulation

Answer 32

treatment phase

Question 33

use of anticoagulants at full or reduced dose for secondary prevention (reducing risk of recurrent VTE events in the future), no preplanned stop date for this phase, should be offered in patients with VTE diagnosed in the setting of a major transient risk factor, reduced dose apixaban or rivaroxaban should be used in this phase

Answer 33

extended phase

Question 34

increased anticoagulation intensity (INR over 5, aPTT over 120 seconds), initiation of therapy (first few days and weeks), unstable anticoagulation response (variable INR response), 65 years of age or older, concurrent antiplatelet drug use, concurrent NSAID/aspirin use, history of GI bleeding, recent surgery or trauma, high risk for fall/trauma, heavy alcohol use, renal failure, cerebrovascular disease, active malignancy

Answer 34

risk factors for major bleeding while on anticoagulation

Question 35

Epistaxis (nosebleed), hemoptysis (coughing up blood), hematuria (blood in the urine), hematemesis (vomiting blood), hematochezia (passage of blood in the stool), melena (black, tarry stools caused by GI bleeding), severe headache, joint pain

Answer 35

signs and symptoms of bleeding that may occur for patients on anticoagulation

Question 36

this type of monitoring should happen daily for hospitalized patients and every 1-3 days for non-hospitalized patients. After initiation, should be monitored every 2-3 days during the first week of therapy. Then once a week for first 1-2 weeks, then every 2 weeks, and eventually monthly thereafter.

Answer 36

INR monitoring for patients on warfarin

Question 37

hepatic metabolism and genotype differences, diet, drug-drug interactions, health status

Answer 37

factors that cause patient specific variations in dosing requirements for warfarin and fluctuation in INR

Question 38

heparin dosing for VTE prevention moderate risk

Answer 38

5000 units Q8-12H

Question 39

heparin dosing for VTE treatment

Answer 39

80 units/kg bolus, 18 units/kg/hr infusion

Question 40

what should be monitored while patients are on heparin?

Answer 40

platelet count to watch for HIT

Question 41

reversal agent for heparin

Answer 41

protamine

Question 42

enoxaparin dosing for VTE prevention moderate risk

Answer 42

40 mg Q24H

Question 43

enoxaparin dosing for VTE prevention high risk

Answer 43

30 mg Q12H or 40 mg Q24H

Question 44

enoxaparin dosing for VTE treatment

Answer 44

1 mg/kg Q12H or 1.5 mg/kg Q24H

Question 45

apixaban dosing for VTE prevention high risk

Answer 45

5 mg BID

Question 46

apixaban dosing for VTE treatment

Answer 46

10 mg BID x 7 days then 5 mg BID, extended phase 2.5 mg BID

Question 47

reversal agent for apixaban and rivaroxaban

Answer 47

andexanet alfa

Question 48

rivaroxaban dosing for VTE prevention high risk

Answer 48

20 mg Q24H

Question 49

rivaroxaban dosing for treatment of VTE

Answer 49

15 mg Q12H x 3 weeks then 20 mg Q24H, extended phase 10 mg Q24H

Question 50

dabigatran dosing for treatment of VTE

Answer 50

after at least 5-10 days of parenteral anticoagulation --> 150 mg Q12H

Question 51

reversal agent for dabigatran

Answer 51

idarucizumab

Question 52

starting dose of warfarin for most patients for VTE treatment

Answer 52

5 mg Q24H x 3 days

Question 53

give _______ when INR is greater than 10 for a patient on warfarin

Answer 53

fresh frozen plasma