NCLEX-RN Pharmacology: Hematologic System
- 20 High-Yield Practice Questions with
Rationales |
ATI-Style & NGN-Aligned
Question 1
Clinical Scenario
A 68-year-old male client with a history of atrial fibrillation is
admitted to the medical-surgical unit with a new diagnosis of
deep vein thrombosis (DVT) in his left lower extremity. He has
been prescribed enoxaparin 1 mg/kg subcutaneously every 12
hours. The client's current weight is 82 kg, and his creatinine
clearance is 45 mL/min. The nurse prepares to administer the
morning dose of enoxaparin. The client's morning laboratory
results show a platelet count of 95,000/mm³, which is a
decrease from 145,000/mm³ three days ago.
Question Stem
Which action should the nurse take first?
,A. Administer the enoxaparin as ordered and monitor for
bleeding
B. Hold the enoxaparin and notify the healthcare provider
C. Administer the enoxaparin and prepare to administer
platelets
D. Reduce the enoxaparin dose based on renal function
Correct Answer
Correct Answer: B. Hold the enoxaparin and notify the
healthcare provider
Detailed Rationale
Correct Answer Explanation: The nurse should hold the
enoxaparin and notify the healthcare provider immediately.
This client is demonstrating signs of heparin-induced
thrombocytopenia (HIT), a serious immune-mediated adverse
reaction to heparin products, including low molecular weight
heparins like enoxaparin. HIT is characterized by a platelet
count drop of ≥50% from baseline, typically occurring 5-10 days
after initiation of therapy. The client's platelet count has
dropped from 145,000 to 95,000/mm³ (a 34% decrease) while
on enoxaparin therapy. HIT paradoxically increases the risk of
thrombosis despite thrombocytopenia, making continued
administration dangerous. The 4Ts scoring system should be
applied; this client's thrombocytopenia and timing (day 3)
,warrant immediate action. Treatment involves discontinuing all
heparin products and initiating a non-heparin anticoagulant
such as argatroban or fondaparinux under provider guidance.
Incorrect Options:
• Option A (Administer the enoxaparin as ordered): This is
unsafe as it could worsen the HIT reaction and increase the
risk of life-threatening thrombosis. Continuing heparin
products in the presence of suspected HIT can lead to
catastrophic outcomes including limb ischemia, pulmonary
embolism, or stroke.
• Option C (Administer the enoxaparin and prepare
platelets): This is incorrect on multiple levels. Platelet
transfusions are contraindicated in HIT because they can
exacerbate the hypercoagulable state and increase
thrombotic risk. Additionally, administering the drug is
unsafe.
• Option D (Reduce the enoxaparin dose based on renal
function): While dose adjustment for renal impairment is
important with enoxaparin, this is not the priority concern.
The platelet drop suggests HIT, not renal insufficiency.
Dose reduction would not address the underlying immune-
mediated reaction.
Nursing Considerations: Monitor for signs of HIT including new
thrombosis, skin necrosis, or systemic reactions. Use the 4Ts
, scoring system to assess HIT probability. Ensure alternative
anticoagulation is initiated before stopping heparin products to
prevent thrombosis.
Learning Objective
After completing this question, the learner should be able to:
• Recognize the signs and symptoms of heparin-induced
thrombocytopenia (HIT)
• Prioritize nursing actions when a client on heparin therapy
develops thrombocytopenia
• Identify medications contraindicated in clients with HIT
• Apply the 4Ts scoring system to assess HIT probability
Medication Safety Focus
High-alert medication; adverse reaction monitoring; medication
safety
Question 2
Clinical Scenario
A 72-year-old female client is receiving warfarin for chronic
atrial fibrillation. Her international normalized ratio (INR) was
2.8 three weeks ago, but today's laboratory results show an INR
of 4.5. The client reports that she "ran out of her blood
- 20 High-Yield Practice Questions with
Rationales |
ATI-Style & NGN-Aligned
Question 1
Clinical Scenario
A 68-year-old male client with a history of atrial fibrillation is
admitted to the medical-surgical unit with a new diagnosis of
deep vein thrombosis (DVT) in his left lower extremity. He has
been prescribed enoxaparin 1 mg/kg subcutaneously every 12
hours. The client's current weight is 82 kg, and his creatinine
clearance is 45 mL/min. The nurse prepares to administer the
morning dose of enoxaparin. The client's morning laboratory
results show a platelet count of 95,000/mm³, which is a
decrease from 145,000/mm³ three days ago.
Question Stem
Which action should the nurse take first?
,A. Administer the enoxaparin as ordered and monitor for
bleeding
B. Hold the enoxaparin and notify the healthcare provider
C. Administer the enoxaparin and prepare to administer
platelets
D. Reduce the enoxaparin dose based on renal function
Correct Answer
Correct Answer: B. Hold the enoxaparin and notify the
healthcare provider
Detailed Rationale
Correct Answer Explanation: The nurse should hold the
enoxaparin and notify the healthcare provider immediately.
This client is demonstrating signs of heparin-induced
thrombocytopenia (HIT), a serious immune-mediated adverse
reaction to heparin products, including low molecular weight
heparins like enoxaparin. HIT is characterized by a platelet
count drop of ≥50% from baseline, typically occurring 5-10 days
after initiation of therapy. The client's platelet count has
dropped from 145,000 to 95,000/mm³ (a 34% decrease) while
on enoxaparin therapy. HIT paradoxically increases the risk of
thrombosis despite thrombocytopenia, making continued
administration dangerous. The 4Ts scoring system should be
applied; this client's thrombocytopenia and timing (day 3)
,warrant immediate action. Treatment involves discontinuing all
heparin products and initiating a non-heparin anticoagulant
such as argatroban or fondaparinux under provider guidance.
Incorrect Options:
• Option A (Administer the enoxaparin as ordered): This is
unsafe as it could worsen the HIT reaction and increase the
risk of life-threatening thrombosis. Continuing heparin
products in the presence of suspected HIT can lead to
catastrophic outcomes including limb ischemia, pulmonary
embolism, or stroke.
• Option C (Administer the enoxaparin and prepare
platelets): This is incorrect on multiple levels. Platelet
transfusions are contraindicated in HIT because they can
exacerbate the hypercoagulable state and increase
thrombotic risk. Additionally, administering the drug is
unsafe.
• Option D (Reduce the enoxaparin dose based on renal
function): While dose adjustment for renal impairment is
important with enoxaparin, this is not the priority concern.
The platelet drop suggests HIT, not renal insufficiency.
Dose reduction would not address the underlying immune-
mediated reaction.
Nursing Considerations: Monitor for signs of HIT including new
thrombosis, skin necrosis, or systemic reactions. Use the 4Ts
, scoring system to assess HIT probability. Ensure alternative
anticoagulation is initiated before stopping heparin products to
prevent thrombosis.
Learning Objective
After completing this question, the learner should be able to:
• Recognize the signs and symptoms of heparin-induced
thrombocytopenia (HIT)
• Prioritize nursing actions when a client on heparin therapy
develops thrombocytopenia
• Identify medications contraindicated in clients with HIT
• Apply the 4Ts scoring system to assess HIT probability
Medication Safety Focus
High-alert medication; adverse reaction monitoring; medication
safety
Question 2
Clinical Scenario
A 72-year-old female client is receiving warfarin for chronic
atrial fibrillation. Her international normalized ratio (INR) was
2.8 three weeks ago, but today's laboratory results show an INR
of 4.5. The client reports that she "ran out of her blood
