Pulmonary Embolism

Question 1

What are the three components of Virchow’s Triad?

Answer 1

• Stasis
• Hypercoagulation
• Endothelial Damage

Question 2

Why is CTPA contraindicated in renal patients?

Answer 2

Due to contrast induced nephropathy

Question 3

What might be found on X-Ray in patients with a PE?

Answer 3

Wedge shaped consolidation

Question 4

What are the options of treatment for patients with a massive PE?

Answer 4

• Thrombolysis i.e. Alteplase, Reteplase
• IVC Filters
• Embolectomy
• Catheter-directed therapy

Question 5

What is the screening tool to assess likelihood of a PE?

What is likely / unlikely score for a PE?

Answer 5

Well’s score
0 - 4 = PE unlikely
>4 = likely

Question 6

Which DVTs most commonly give rise to pulmonary embolisms? Iliofemoral or distal DVTs?

Answer 6

Distal DVTs = more common

Iliofemoral DVT = less common but more likely to cause a PE

Question 7

Give two examples of mechanical VTE Prophylaxis

Answer 7

Anti-embolic stockings

Intermittent pneumatic compression device `

Question 8

PULMONARY EMBOLISM

1. What is it?
2. What are risk factors?
3. How might you initially determine how to investigate a suspected PE?
4. If a D-Dimer is negative, what is the outcome?
5. If CTPA is negative, what is the outcome?
6. If a D-Dimer is positive, what is the outcome?
7. If you are awaiting for a CTPA or D-Dimer, what can be done in mean time?
8. What are some findings on ECG in a patient with PE?
9. What are some findings on CXR in a patient with PE?
10. What are some findings on ABG in a patient with PE?
11. In patients with provoked PE, how long is treatment?
12. In patient with unprovoked PE, how long is treatment?
13. In patient hemodynamically unstable with PE, what is treatment?
14. What is the first line anticoagulation for PE?
15. What is first line anticoagulation for PE in renal impairment patients?
16. What is first line anticoagulation for PE in cancer patients?

Answer 8

1. A blood clot forms in the pulmonary arteries
2. Immobility, recent surgery, long haul flights, pregnancy, HRT + Oestrogen, malignancy, SLE
3. If you think low probability <15%, use PERC criteria. If all negative, then very low probability. If any are positive, continue with Wells Score. Wells Score if below 4, then D-Dimer, if above 4, CTPA
4. Reconsider PE diagnosis
5. Proximal leg vein ultrasound
6. Perform a CTPA
7. Give anticoagulation in mean time, i.e. DOAC Apixaban / Rivaroxaban
8. Sinus tachycardia, RBBB, RAD, S1Q3T3
9. Usually normal, may have wedge shaped opacification
10. Respiratory alkalosis
11. 3 months
12. 6 months
13. Thrombolysis
14. DOAC i.e. Apixaban, Rivaroxaban
15. LMWH initially followed by UFH or Vitamin K antagonist
16. DOAC i.e. Apixaban, Rivaroxaban