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After completing this case study, the reader should be able to:

  • Identify the signs, symptoms, and risk factors associated with pulmonary embolism (PE).

  • Evaluate a patient for heparin-induced thrombocytopenia (HIT).

  • Select an appropriate anticoagulant for the treatment of PE complicated by HIT.

  • Monitor anticoagulation therapy for the treatment of PE complicated by HIT.

  • Educate a patient on anticoagulation therapy.


Chief Complaint

“I’m having chest pain, and I can’t catch my breath.”


Mary Anton is a 70-year-old woman who arrives at the hospital’s emergency department by ambulance transfer from her home. The patient is S/P right TKR (postoperative day 10) for severe osteoarthritis. She was discharged from the hospital’s orthopedic nursing unit 4 days ago with a prescription for enoxaparin for DVT prophylaxis. The patient was scheduled to receive physical therapy at a local rehabilitation center; however, she canceled therapy due to pain. She has been inactive at home with the exception of completing her activities of daily living with the assistance of her husband. This morning, the patient developed sharp chest pain and shortness of breath while watching television. She denies nausea, vomiting, and diaphoresis. The patient has a nonproductive cough. She is anxious and complains of pain in her right knee and right lower extremity.


HTN × 30 years

Dyslipidemia × 25 years

Chronic stable angina × 2 years (negative regadenoson stress test 2 months ago)

CKD secondary to previously uncontrolled HTN, stage 4 (baseline creatinine 1.8–2.0 mg/dL)



S/P TKR right leg (postoperative day 10)


Father died at age 74 (lung CA)

Mother died at age 89 (MI)

No siblings


The patient is retired. She lives at home with her husband. Prior to surgery, she avoided most physical activity due to severe osteoarthritis. Negative for tobacco abuse. Denies alcohol use.


Home medications:

Aspirin 81 mg PO once daily

Metoprolol succinate 100 mg PO daily

Amlodipine 10 mg PO once daily

Hydralazine 50 mg PO TID

Atorvastatin 20 mg PO once daily

Nitroglycerin 0.4 mg sublingually PRN chest pain

Sevelamer carbonate 1600 mg PO TID with meals

Enoxaparin 30 mg subcutaneously Q 24 hours

Oxycodone sustained release 20 mg PO Q 12 hours


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