Venous air embolism in sitting position surgery

The incidence of VAE in posterior fossa surgery in the sitting position is reported to be 41– 45% with routine monitoring.

However, with the use of Doppler ultrasound the reported incidence is as high as 42–85%.

VAE often is clinically undetected and frequently not of serious concern in a healthy patient if the volume and rate of air entrainment are minimal.

The amount of entrained air that is reported to be lethal in humans is approximately 300 mL.

Significant morbidity and mortality from VAE is now <1% predominantly as a result of better monitoring techniques, early detection, and prompt intervention.

Sitting position is contraindicated in patients with documented intracardiac defects or arteriovenous malformations because of the risk of paradoxical air embolism . Patent foramen ovale is the most common congenital defect associated with a paradoxical air embolus.

Children generally have greater clinically significant hemodynamic derangement from VAE than do adults.

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