Retrograde Venous Cerebral Air Embolism from Disconnected Central Venous Catheter: An Experimental Model

Abstract

There are few reported cases of death attributed to retrograde cerebral air embolism from central venous catheter. The pathophysiological mechanism and the necessary conditions are not fully understood, also because of missing experimental data. We performed experimental simulation while working on a possible case of retrograde cerebral air embolism. A hermetic system consisting of two containers connected to each other and to an electric pump by means of rubber hoses was built. In this system, a fluid (water and blood) could continuously flow under conditions similar to those of the common jugular vein. The part of the system representing the jugular vein could be freely positioned at angles between 0 and 90°. A central venous catheter was inserted into this part. After disconnection, the behavior of the air bubbles entering the hose through the tip of the catheter was evaluated at different positions. At angles between 0 and 45°, the air bubbles followed the fluid flow. At angles >45°, the air bubbles showed the tendency to flow upstream; this phenomenon was more evident the more vertically the hose was located. We were able to demonstrate that a retrograde air embolism can be caused by a disconnected catheter and is even more likely if the neck is in a vertical position.

Vascular air embolism

“…An even more sensitive and definitive method for detecting intracardiac gas is transesophageal echocardiography is frequently utilized by anesthesiologists to monitor patients in high-risk procedures. [21017–22]…”

Cerebral Venous Air Embolism: A Rare Phenomenon

“…The entry of air into the venous circulation occurs after manipulation of a central or peripheral vessel (the latter case is less commonly described). Jugular vein insufficiency due to lack of valves and increased intrathoracic pressure have been proposed as factors contributing to CVAE [3,4] . CVAE's symptoms are non-specific, with dizziness, vertigo, headache, confusion/disorientation, altered mental state, syncope, seizures, speech impairment, blurred vision, motor or sensory deficits and ataxia, mimicking other neurological disorders, such as acute stroke [4] .…”

Pulmonary Cement Embolism After Kyphoplasty

“…CVC insertion is a common procedure performed in hospitalized patients. In most institutions, a postprocedure chest X-ray is obtained routinely to confirm the position of the CVC and to rule out complications such as a CVC distal fragment embolization (12)(13)(14) or air embolism (15). The diagnosis of the nature of the embolism, as in the current case reported by the authors, is important for both clinical and legal purposes.…”