Blood Clot/Bleeding

Question 1

You have hospitalized a 67-year-old obese white female for urosepsis. She has completed a course of intravenous antibiotics. She has hypertension, diabetes mellitus, and congestive heart failure. In addition, she has renal failure which has worsened, and she has been on hemodialysis for 1 week. The chart lists her medications as enalapril (Vasotec), furosemide (Lasix), labetalol (Trandate, Normodyne), insulin, and heparin for flushing intravenous lines. For the past 2 days she has had nosebleeds. A CBC is normal except for mild anemia and marked thrombocytopenia of 28,000/mL. Which one of the following is most likely the cause of her thrombocytopenia? (check one)
Enalapril
Furosemide
Labetalol
Insulin
Heparin

Answer 1

Heparin

A number of medications can cause thrombocytopenia, but heparin is a more likely cause than enalapril, furosemide, labetalol, or insulin. Even the small doses of heparin used to flush intravenous lines can be a source of thrombocytopenia.

Question 2

A 57-year-old male sees you for follow-up of a first episode of a distal deep vein thrombosis (DVT). He is currently taking apixaban (Eliquis) and has had no complications. He has no past medical history, including surgery or hospitalization, and he has not traveled recently. His vital signs today include a heart rate of 70 beats/min and a blood pressure of 118/76 mm Hg. His BMI is 32 kg/m2. A physical examination is otherwise unremarkable.

Which one of the following would be the most appropriate duration of treatment for an unprovoked first DVT? (check one)
No treatment
6 weeks
3 months
6 months
Indefinite

Answer 2

Indefinite

Venous thromboembolism (VTE) is a common occurrence and is the cause of up to 100,000 deaths per year in the United States. When determining a course of treatment, it is key to identify whether the VTE or deep vein thrombosis (DVT) was caused by a temporary or transient risk factor. Common transient risk factors include surgery, hospitalization, trauma, and prolonged travel. VTE in the setting of a transient risk factor should be treated with anticoagulation for 3 months. In this patient’s case, there is no obvious transient risk factor. However, obesity and male sex may be considered chronic or persistent risk factors. In this setting, the rate of recurrence in the first year is as high as 10.3%. NICE and CHEST guidelines recommend an indefinite duration of treatment for VTE that is due to chronic risk factors or VTE that is otherwise unprovoked (SOR C). Risk factors for bleeding should prompt consideration to discontinue treatment. While guidelines include the option for serial ultrasonographic monitoring of distal DVT without anticoagulation, this course of action is not recommended in patients with unprovoked DVT. Neither 6 weeks nor 6 months are established treatment durations.

Question 3

Which one of the following is the recommended duration of anticoagulation for a first episode of a provoked proximal deep vein thrombosis of the leg? (check one)
6 weeks
3 months
9 months
1 year
Lifelong

Answer 3

3 months

The 2016 CHEST guideline and expert panel report gives a strong recommendation (Grade 1B) to support 3 months of anticoagulation after a first episode of a provoked proximal deep vein thrombosis (DVT) of the leg. Treatment for 3 months appears to be superior to shorter treatment (6 weeks) with regard to recurrence of DVT. Treatment regimens >6 months for an unprovoked DVT may slightly reduce the rate of recurrence, but this is offset by an increased rate of bleeding and mortality.

Question 4

A 67-year-old female with hypertension and atrial fibrillation has been taking warfarin (Coumadin) for the past 10 years. She has been hemodynamically stable for many years with no complications from her atrial fibrillation. She is scheduled to undergo elective bladder sling surgery for urinary incontinence. She does not have any other significant past medical history.

Which one of the following would be the most appropriate perioperative management of her warfarin? (check one)
Continue warfarin without interruption
Discontinue warfarin the day prior to surgery and provide bridge therapy with low molecular weight heparin
Discontinue warfarin 2 days prior to surgery and restart it 2 days postoperatively unless there is a bleeding complication
Discontinue warfarin 2 days prior to surgery and restart it 5 days postoperatively unless there is a bleeding complication
Discontinue warfarin 5 days prior to surgery and restart it 12–24 hours postoperatively unless there is a bleeding complication

Answer 4

Discontinue warfarin 5 days prior to surgery and restart it 12–24 hours postoperatively unless there is a bleeding complication

Perioperative management of chronic anticoagulation requires an assessment of the patient’s risk for thromboembolism and the risk of bleeding from the surgical procedure. High-risk patients include those with mechanical heart valves, a stroke or TIA within the past 3 months, venous thromboembolism within the past 3 months, or coronary stenting within the previous 12 months. High-risk patients require bridging therapy with low molecular weight heparin, while patients at low risk do not require bridging anticoagulation. For low-risk patients, it is recommended that warfarin be discontinued 5 days prior to surgery and restarted 12–24 hours postoperatively. This patient is at low risk for thromboembolism because her CHA2DS2-VASc score is 3. A patient with atrial fibrillation should receive bridging therapy with a CHA2DS2-VASc score 6. This patient’s surgery is associated with a high risk for bleeding, so it is preferable to stop her warfarin 5 days before the operation.

Question 5

A 25-year-old gravida 1 para 0 at 24 weeks gestation comes to your office with right lower extremity swelling and pain. Her pregnancy has been uncomplicated so far and her only medication is a prenatal vitamin. She does not have chest pain, shortness of breath, or fever. She recently started feeling the baby move, and an anatomy scan at 20 weeks gestation was normal.

Lower extremity Doppler ultrasonography confirms a right lower extremity deep vein thrombosis (DVT). Laboratory studies including a CBC, coagulation studies, and renal function are normal.

Which one of the following would be the most appropriate initial treatment of her DVT? (check one)
Oral apixaban (Eliquis)
Oral aspirin
Oral warfarin (Coumadin)
Subcutaneous enoxaparin (Lovenox)
Subcutaneous heparin

Answer 5

Subcutaneous enoxaparin (Lovenox)

Enoxaparin is the most appropriate pharmacologic therapy for anticoagulation in patients who are pregnant. Aspirin is not used as treatment for deep vein thrombosis. Apixaban, warfarin, and heparin either have not been studied for use in pregnancy or there is data indicating potential fetal harm.

Question 6

The novel anticoagulants (NOACs) include apixaban (Eliquis), dabigatran (Pradaxa), edoxaban (Savaysa), and rivaroxaban (Xarelto). Which one of the following should be considered when starting or adjusting the dosage of a NOAC? (check one)
Serum albumin
INR
Liver enzymes
Partial thromboplastin time
Renal function

Answer 6

Renal function

The novel anticoagulants (NOACs) require dosage adjustments based on renal function. There are no dosing recommendations for NOACs based on liver function or albumin level. The INR is used to adjust warfarin dosing and the partial thromboplastin time is used to adjust heparin dosing.

Question 7

An 85-year-old female with a previous history of diabetes mellitus, hypertension, dementia, and peptic ulcer disease has been in a skilled nursing facility for 4 weeks for rehabilitation after a hip fracture repair secondary to a fall during an ischemic stroke. She is transported to the emergency department today when she develops confusion, shortness of breath, and diaphoresis. Her blood pressure is 172/98 mm Hg, her heart rate is 122 beats/min with an irregular rhythm, and her respiratory rate is 22/min. An EKG demonstrates atrial fibrillation and 0.2 mV ST-segment elevation compared to previous EKGs. Her first troponin level is elevated.

Which one of the following conditions in this patient is considered an ABSOLUTE contraindication to fibrinolytic therapy?
(check one)
Poorly controlled hypertension
Peptic ulcer disease
Alzheimer’s dementia
Hip fracture repair
Ischemic stroke

Answer 7

Ischemic stroke

A history of an ischemic stroke within the past 3 months is an absolute contraindication to fibrinolytic therapy in patients with an ST-elevation myocardial infarction (STEMI), unless the stroke is diagnosed within 4½ hours. Poorly controlled hypertension, dementia, peptic ulcer disease, and major surgery less than 3 weeks before the STEMI are relative contraindications that should be considered on an individual basis.

Question 8

Three weeks after he had knee surgery, a 64-year-old male presents for follow-up of an emergency department visit for a pulmonary embolism. He has no previous history of pulmonary embolism and is otherwise in good health. He is being treated with apixaban (Eliquis).

The recommended duration of anticoagulation therapy for this patient is
(check one)
1 month
3 months
6 months
9 months
12 months

Answer 8

3 months

Patients who have a venous thromboembolism (VTE) require anticoagulation therapy for treatment and
prevention of recurrence. The risk of recurrence is greatest in the first year after the event and remains
elevated indefinitely. The risk for VTE recurrence is dependent on patient factors, such as active cancers
and thrombophilia. Current guidelines recommend treatment for at least 3 months. In patients who have
a reversible provoking factor such as surgery, anticoagulation beyond 3 months is not recommended.

Question 9

A 62-year-old male with diabetes mellitus recently underwent angioplasty with placement of a drug-eluting stent for the treatment of left main coronary artery disease and acute coronary syndrome. The patient is not considered at high risk for bleeding and you initiate dual antiplatelet therapy with aspirin and clopidogrel (Plavix).

For how long should this patient continue dual antiplatelet therapy? (check one)
1 month
3 months
6 months
9 months
At least 12 months

Answer 9

At least 12 months

Dual antiplatelet therapy should extend beyond 1 year for patients with acute coronary syndrome who are not considered at high risk of bleeding, especially those with risk factors associated with high ischemic risk such as diabetes mellitus, peripheral artery disease, left main stenting, or a history of a cardiovascular event. For dual antiplatelet therapy that continues beyond a year, either ticagrelor, 60 mg twice daily, or clopidogrel, 75 mg daily, is recommended in addition to aspirin. The patient’s bleeding and ischemic risk should be reevaluated at least annually.
Dual antiplatelet therapy should continue for at least 1 year in patients who are considered at high risk of bleeding. For patients who are at very high risk of bleeding or who experience significant bleeding while on dual antiplatelet therapy, a duration of less than 1 year is recommended.