40 DIFFICULT MULTIPLE CHOICE QUESTIONS (MCQs)

1. Which best describes the mechanism of ASA (aspirin) in antiplatelet therapy?

A) COX inhibition to reduce thromboxane A2
B) Direct thrombin inhibition
C) ADP receptor blockade
D) Factor Xa inhibition
Answer: A

2. A patient with a CYP2C19 polymorphism may have reduced efficacy with:

A) ASA
B) Clopidogrel
C) Dabigatran
D) Enoxaparin
Answer: B

3. Which laboratory test is used to monitor heparin therapy?

A) INR
B) PT
C) aPTT
D) CBC
Answer: C

4. What is the primary role of thrombin in coagulation?

A) Activates antithrombin
B) Degrades fibrin
C) Converts fibrinogen to fibrin
D) Activates vitamin K
Answer: C

5. Warfarin exerts its effect by:

A) Directly inhibiting thrombin
B) Binding to AT III
C) Inhibiting synthesis of vitamin K-dependent factors
D) Activating protein C
Answer: C

6. What is a major adverse effect of heparin that can occur even with low doses?
A) Hypertension
B) Petechial hemorrhages
C) Heparin-induced thrombocytopenia (HIT)
D) Cardiac arrhythmias
Answer: C
7. Which statement about LMWH (e.g. enoxaparin) is TRUE?
A) Requires daily aPTT monitoring
B) Has higher selectivity for Factor IIa
C) Is less predictable in response than UFH
D) Preferentially inhibits Factor Xa
Answer: D

8. Dabigatran’s key benefit over warfarin is:

A) Enhanced effect with vitamin K
B) Oral absorption without food restriction
C) Predictable effect with fewer drug interactions
D) Ability to dissolve clots
Answer: C

9. The anticoagulant effect of fondaparinux relies on:

A) Direct inhibition of thrombin
B) Vitamin K antagonism
C) Activation of antithrombin III to inactivate Factor Xa
D) COX inhibition
Answer: C

10. Which factor is NOT affected by vitamin K antagonism?

A) Factor II
B) Factor V
C) Factor IX
D) Factor X
Answer: B

11. A patient with bruising and INR of 6.5 on warfarin should receive:
A) Fresh-frozen plasma
B) Enoxaparin
C) Dabigatran
D) Streptokinase
Answer: A

12. Which antiplatelet drug must be converted to its active form by CYP enzymes?
A) ASA
B) Prasugrel
C) Ticagrelor
D) Clopidogrel
Answer: D

13. Which drug is contraindicated in pregnancy?

A) Enoxaparin
B) Dabigatran
C) Warfarin
D) ASA
Answer: C

14. Which test is used to monitor warfarin therapy?

A) aPTT
B) INR
C) Anti-Xa
D) TSH
Answer: B

15. Why must INR be closely monitored in warfarin therapy?

A) Warfarin increases platelet count
B) Warfarin prolongs aPTT
C) Warfarin has a narrow therapeutic window and is affected by diet and drugs
D) Warfarin directly dissolves clots
Answer: C

16. The antidote for heparin toxicity is:

A) Vitamin K
B) Protamine sulfate
C) Activated charcoal
D) Dabigatran
Answer: B

17. Which drug class is considered a “clot buster”?

A) Antiplatelets
B) Anticoagulants
C) Thrombolytics
D) Antifibrinolytics
Answer: C

18. Which thrombolytic is associated with hypersensitivity after first use?

A) Alteplase
B) Tenecteplase
C) Streptokinase
D) Reteplase
Answer: C

19. Which coagulation factor initiates the extrinsic pathway?

A) Factor X
B) Thrombin
C) Tissue factor + Factor VII
D) Fibrin
Answer: C
20. Which is a direct Factor Xa inhibitor?
A) Fondaparinux
B) Rivaroxaban
C) Enoxaparin
D) Clopidogrel
Answer: B

21. Tranexamic acid is used to:

A) Enhance fibrinolysis
B) Inhibit platelet aggregation
C) Prevent clot breakdown
D) Promote thrombin activation
Answer: C

22. Which patient is most at risk of treatment failure with clopidogrel?

A) Rapid metabolizer of CYP3A4
B) CYP2C19 slow metabolizer
C) Vitamin K-deficient patient
D) Renal failure patient
Answer: B

23. Dabigatran inhibits:

A) Thrombin
B) Factor Xa
C) Cyclooxygenase
D) ADP
Answer: A

24. Antithrombin III inactivates all EXCEPT:

A) Factor Xa
B) Thrombin
C) Factor VII
D) Factor XIa
Answer: C

25. Which condition is treated acutely with thrombolytics?

A) DVT
B) Ischemic stroke
C) Hemophilia
D) HIT
Answer: B

26. Which symptom most likely indicates internal bleeding with heparin therapy?
A) Diarrhea
B) Petechiae and hypotension
C) Tachycardia without other symptoms
D) Blurred vision
Answer: B

27. Which best describes the action of ADP receptor blockers like ticagrelor?
A) COX inhibition
B) Vitamin K antagonism
C) Blocking platelet activation by ADP
D) Enhancing AT III function
Answer: C

28. The INR goal for warfarin therapy in most patients is:
A) 1.0–1.5
B) 1.5–2.0
C) 2.0–3.5
D) 3.5–5.0
Answer: C

29. Why do LMWHs have fewer bleeding complications than UFH?

A) Lower potency
B) Higher selectivity for thrombin
C) Shorter half-life
D) Preferential inhibition of Factor Xa
Answer: D

30. Which drug inhibits both Factor Xa and thrombin equally via AT III?
A) Dabigatran
B) Warfarin
C) Unfractionated heparin
D) Rivaroxaban
Answer: C

31. Which anticoagulant requires no routine blood monitoring?

A) Heparin
B) Warfarin
C) Dabigatran
D) Streptokinase
Answer: C

32. Which anticoagulant is administered subcutaneously and selectively activates AT III to inhibit
Factor Xa only?
A) Enoxaparin
B) Fondaparinux
C) Rivaroxaban
D) Warfarin
Answer: B

33. What adverse effect is unique to long-term, high-dose heparin?

A) Dyspepsia
B) Osteoporosis
C) Bradycardia
D) Seizures
Answer: B

34. Which adverse effect can occur with all anticoagulants and thrombolytics?
A) Neutropenia
B) Hypokalemia
C) Bleeding
D) Tachycardia
Answer: C

35. How do thrombolytics like tPA work?

A) Block ADP receptors
B) Inhibit Factor Xa
C) Convert plasminogen to plasmin to break fibrin
D) Inhibit COX enzymes
Answer: C

36. Which drug combination would increase risk of bleeding the most?
A) Warfarin + tPA
B) ASA + tranexamic acid
C) Clopidogrel + fondaparinux
D) Heparin + rivaroxaban
Answer: A

37. What is the purpose of prothrombin complex concentrate in warfarin overdose?

A) Promote ADP receptor antagonism
B) Provide plasma volume
C) Restore clotting factors II, VII, IX, X
D) Reduce gastric irritation
Answer: C

38. A key difference between thrombolytics and anticoagulants is:

A) Thrombolytics prevent clot formation
B) Anticoagulants dissolve existing clots
C) Thrombolytics break down existing clots
D) Anticoagulants increase platelet production
Answer: C
39. Streptokinase is not reused because:
A) It's ineffective in older adults
B) It is highly toxic
C) It causes immunogenicity after first use
D) It increases potassium levels
Answer: C

40. Which drug reduces fibrinolysis by preventing plasminogen binding to fibrin?

A) tPA
B) Tranexamic acid
C) Rivaroxaban
D) Dabigatran
Answer: B

10 SHORT-ANSWER QUESTIONS (1–2 Sentences Max)

1. Why is warfarin not effective immediately?
Answer: It only affects newly synthesized clotting factors, so full effect requires 3–4 days.

2. How does heparin exert its anticoagulant effect?

Answer: It activates antithrombin III, which inactivates Factor Xa and thrombin equally.

3. What is the main clinical use of thrombolytics like tPA?

Answer: To dissolve acute clots in conditions like ischemic stroke or myocardial infarction.

4. Why must INR be monitored in patients on warfarin?

Answer: Because warfarin has a narrow therapeutic range and is affected by diet and drug
interactions.

5. What is a major risk of using thrombolytics?

Answer: Intracranial hemorrhage or rebleeding at recent injury sites.

6. How is clopidogrel’s effectiveness affected by genetics?

Answer: Poor CYP2C19 metabolizers may not activate enough drug, reducing efficacy.

7. Why does ASA increase bleeding time?

Answer: It irreversibly inhibits COX enzymes, reducing thromboxane A2 and platelet
aggregation.

8. When is protamine sulfate used?

Answer: As an antidote to reverse heparin toxicity or overdose.
9. What is the benefit of LMWH over UFH?
Answer: LMWH has more predictable dosing and fewer bleeding risks due to selective Factor
Xa inhibition.

10. What is the role of tranexamic acid?

Answer: It reduces fibrinolysis by preventing plasminogen from binding to fibrin, thus preserving
clots.

PHA 3112 – Hemostasis Drugs: EXAM REVIEW

TRUE or FALSE

Enter T for true, F for false.

1. ___ Patients who take anticoagulant, antiplatelet, and thrombolytic drugs are at risk for
bleeding.
2. ___ Pregnant or nursing patients should never be prescribed heparin.
3. ___ Anticoagulant and antiplatelet drugs only affect the formation of clots, not removal.
4. ___ When given at prescribed doses, anticoagulant and antiplatelet drugs can cause
unintended bleeding.
5. ___ Hemostasis is a synonym for clot.
6. ___ Aggregation means clustering.

CRITICAL THINKING / PRIORITIZATION

7. Why can’t heparin be given orally?

a. Prolonged half-life orally
b. Bitter oral formulation
c. Destroyed by GI proteases
d. Poorly absorbed due to size/charge

8. Which abnormal lab result would be priority to report in a patient on heparin?

a. aPTT 75 seconds
b. BUN 22
c. Platelets 40,000
d. WBC 11,000

9. What should the nurse do if a patient on heparin reports possible pregnancy?

a. Give heparin and notify prescriber
b. Withhold heparin
c. Confirm pregnancy first
d. Give protamine sulfate

10. Which teaching is best to prevent a common adverse effect of long-term, high-dose
heparin?
a. Avoid crowds
b. Weight-bearing exercise
c. Increase fiber and fluids
d. Use OTC antacids

11. What should the nurse do about a heparin dose scheduled at 0900 on day of 1000 surgery?
a. Give both doses
b. Give 0900 only, question 2100
c. Hold both doses
d. Give 2100 only, question 0900

12. What is the correct protamine sulfate dose for 4000 units of heparin?
a. 10 mg
b. 20 mg
c. 40 mg
d. 60 mg

13. Which aPTT indicates therapeutic range for heparin?

a. 30–40 seconds
b. 40–50 seconds
c. 60–80 seconds
d. 90–120 seconds

14. If IV heparin is scheduled every 6 hours (1200, 1800, 2400, 0600), when should aPTT labs
be drawn?
a. 0800
b. 0900 and 2100
c. 1000, 1600, 2200
d. 1100, 1700, 2300, 0500

15. After starting subQ heparin, which symptom is most concerning?

a. Injection site bruising
b. Headache and faintness
c. Mild fever
d. Pink saliva

16. Which drug requires aPTT monitoring?

a. Fragmin
b. Heparin
c. Warfarin
d. Lovenox

17. Which statements are TRUE about enoxaparin? (Select all)

a. More expensive than UFH
b. Dose may be weight-based
c. May combine with ASA for angina
d. Protamine is effective antidote
e. BID dosing = every 12 hrs

18. What is priority concern if enoxaparin is prescribed before hip surgery?

a. Warfarin also ordered
b. eGFR 85
c. INR 1.2
d. Spinal anesthesia planned

19. Which OTC products increase warfarin bleeding risk? (Select all)
a. Acetaminophen
b. ASA
c. Cimetidine
d. Glucosamine/chondroitin
e. Vaginal miconazole

20. What foods should warfarin users eat in consistent amounts? (Select all)
a. Citrus
b. Liver
c. Green leafy vegetables
d. Mayonnaise
e. Red meat

21. What should a warfarin patient do before dental surgery?

a. Nothing
b. Show INR to dentist
c. Stop warfarin 3 days before
d. Halve the dose for 3 days

22. How long after stopping warfarin should bleeding precautions continue?
a. 6 hrs
b. 8–12 hrs
c. 2.5 days
d. 5 days

23. What lab result requires urgent consult in a patient on dabigatran?

a. ALT 65
b. eGFR 14
c. hCG 2
d. Na+ 140

24. What is priority assessment for a patient on bivalirudin?

a. BP lying and sitting
b. I&O
c. Pain with movement
d. Sleep

25. Which statement shows understanding of rivaroxaban after knee surgery?

a. “I’ll use a soft toothbrush and electric razor.”
b. “I won’t touch the needle when injecting.”
c. “I’ll get monthly blood tests.”
d. “If I get short of breath, I’ll rest.”

26. Which statement shows need for more aspirin education?

a. “Tell my pharmacist.”
b. “Quit smoking.”
c. “Avoid stomach acid drugs.”
d. “Enteric-coated aspirin won’t hurt my stomach.”

27. Clopidogrel + greenish emesis with brown specs → next step?

a. Full physical assessment
b. Request emesis Hematest
c. Order antiemetic
d. Stop clopidogrel

28. Initial digoxin 0.6 ng/mL + ticagrelor due → action?

a. Give digoxin only
b. Give ticagrelor only
c. Give both
d. Hold both and notify

29. Which ticlopidine side effect requires urgent action?

a. LOC changes
b. Diarrhea
c. Dyspepsia
d. Itchy rash

30. WBC 3000, neutrophils 30% on ticlopidine → priority?

a. Cardiac output
b. Airway
c. Skin care
d. Infection prevention
31. Abciximab + lump/pain at PCI site → what do you do? (Select all)
a. Administer oxygen
b. Apply pressure
c. Bedrest
d. Mark bleeding
e. Order CT scan

32. Most significant disadvantage of dipyridamole + aspirin?

a. Cost
b. Dosing
c. Doesn’t contain recommended aspirin dose
d. Doesn’t contain recommended dipyridamole dose

33. Which food increases bleeding with cilostazol?

a. Cabbage
b. Dairy
c. Grapefruit juice
d. Green vegetables

34. What is top teaching priority for family of MI-risk patient?

a. “Drugs can open clogged arteries.”
b. “Donate blood.”
c. “Get help right when symptoms start.”
d. “Thrombolytics increase bleeding risk.”

35. Which is FALSE about Anti-Factor Xa Heparin Assay?

a. Indirectly measures heparin
b. Not affected by physiologic variables
c. Range: 0.3–0.7 IU/mL
d. Costs more than aPTT

36. PAR-1 antagonists + aspirin/clopidogrel are used in patients with: (Select all)
a. Venous occlusion
b. MI
c. Carotid stenosis
d. Peripheral arterial disease

DOSE CALCULATION

37. You are ordered 50 mg protamine sulfate IV. Stock is 10 mg/mL. How many mL do you
administer?
38. Tirofiban: 220-lb patient. Stock: 12.5 mg/250 mL. What is the IV rate in mL/hr?
 CASE STUDY

Patient: 36-year-old woman, 132 lbs, frequent long-haul flyer, admitted for DVT in right thigh.
Primary care provider did not prescribe aspirin.

1. How should the nurse respond to the spouse's question about aspirin?
2. What is the most common adverse effect of heparin, and what symptoms should be
monitored?
3. The patient is switched from heparin drip to enoxaparin 60 mg SC q12h. When should
enoxaparin be started after stopping heparin and why?

ANSWER KEY
TRUE/FALSE:

1. T 2. F 3. T 4. T 5. F 6. T

CRITICAL THINKING:

7. d 8. c 9. a 10. b 11. d 12. b 13. c 14. d 15. b 16. b

8. a, b, c, d, e 18. d 19. a, b, c, d, e 20. b, c, d
9. b 22. d 23. b 24. a 25. a 26. d 27. b 28. c 29. a 30. d
10. b, c, d 32. c 33. c 34. c 35. b (FALSE) 36. b, c, d

DOSE CALCULATIONS:

37. 50 mg ÷ 10 mg/mL = 5 mL
38. 220 lbs ÷ 2.2 = 100 kg → rate = 0.1 mcg/kg/min × 60 = 6 mL/hr (assuming standard
protocol)

CASE STUDY:

1. Low-dose aspirin is not effective at preventing DVTs; anticoagulants like heparin are
used instead.
2. Most common adverse effect is bleeding—monitor for bruising, petechiae, hematuria,
melena, hypotension, and headache.
3. Wait at least 1–2 hours to avoid overlapping anticoagulant effects and excessive
bleeding risk.