OnlineMedEd: Intern Content - "Pulmonary Embolism"

Question 1

Once again, review Virchow’s triad.

Answer 1

• Venous stasis
• Endothelial injury
• Hypercoagulable state

Question 2

If one leg is ____ bigger than the other, then you should do an US to look for DVT.

Answer 2

> 2 cm

Question 3

Why does a small embolus in a subsegmental lobe cause hypoxemia?

Answer 3

The embolus releases platelet-derived mediators that cause vasoconstriction of the arterioles. This increases the diffusion distance of all the alveoli-arteriole barriers and thus leads to hypoxemic, hypocapnic respiratory alkalosis.

Question 4

Describe how Well’s scoring is done.

Answer 4

• Well’s ≥ 4: get a CTPE
• Well’s 3,4: do not get a CTPE
• Well’s <2: get a D-dimer to rule out

Question 5

Review the definition and management of each of the following: 
•Asymptomatic PE
•Symptomatic PE
•Submassive PE
•Massive PE

Answer 5

•Asymptomatic PE:

• PE discovered incidentally, no change in vitals, no right heart strain
• D/C home on LMWH to warfarin

•Symptomatic PE:

• Symptomatic (e.g., SOB, pleuritic chest pain), hypoxemic
• Admit to floor with LMWH to warfarin, D/C after they respond well to anticoagulation

•Submassive PE:

• Symptomatic (e.g., SOB, pleuritic chest pain), right heart strain, hypoxemic
• ICU

•Massive PE:

• Symptomatic, right heart strain, hypoxemic, hypotension
• ICU with tPA

Question 6

How do you assess for right heart strain?

Answer 6

• TTE
• BNP
• Troponin