The Annals of thoracic surgery
-
This study evaluates the role of increased intratracheal pressure in developing systemic air embolization. Twenty healthy mongrel dogs were monitored for air embolization, both by means of an extracorporeal arteriovenous shunt constructed from transparent plastic tubing for visualization of air emboli and by means of a Doppler flow probe implanted at the root of the aorta. Systemic arterial, left atrial, intratracheal, and intrapleural pressures were recorded. ⋯ However, systemic air embolization occurred in every dog in all groups upon hyperinflation of the lung above 65 mm Hg. The control groups differed from the groups with penetrating wound only in the quantity of embolized air. This study suggests that hyperinflation of the lung to an intratracheal pressure above 65 mm Hg results in systemic air embolization and that the presence of a penetrating wound of the lung at such intratracheal pressure predisposes to a greater quantity of air embolization.