Venous Air Embolism

Question 1

What is a venous air embolus?

Answer 1

Air introduced into the vascular system, resulting in a spectrum of clinical effects from the asymptomatic patient to shortness of breath to cardiovascular collapse.

Question 2

What are the clinical features of a venous air embolism?

Answer 2

1. Sudden drop in EtCO2 may be first sign as dead space increases. PaCO2 will rise concomitantly.
2. Mill-wheel continuous murmur is rare and usually only heard with massive VAE
3. Increased end-tidal N2 concentration
4. SOB
5. CV collapse

Question 3

How might CVP be helpful in noticing and treating a venous air embolism?

Answer 3

1. CVP pressures may elevate

2. May be able to use CVL to aspirate air from right atrium

Question 4

What is the most sensitive monitor for detection of a venous air embolus?

Answer 4

TEE

Question 5

Which is more sensitive precordial doppler or EtCO2 for the detection of a venous air embolism?

Answer 5

Doppler is twice as sensitive as EtCO2 for detection of a venous air embolism.

Question 6

What is the differential diagnosis when assessing for venous air embolism?

Answer 6

1. Pulmonary thromboembolism, fat embolism, amniotic embolism
2. Brain-stem retraction/ischemia
3. Other causes of hypotension
4. Entrainment of air into respiratory gas analyzer

Question 7

What is the management of venous air embolism?

Answer 7

1. Prevent further air entry (inform surgeon, flood the field, compress wound if possible, discontinue N2O, add PEEP to increase venous pressure
2. Minimize CV impact (left lateral decubitus position, trendelenburg, aspirate if CVL in place)
3. Maintain cardiac output w/ fluids, inotropes
4. 100% FiO2