Trendelenburg Position After Cerebral Air Embolism in Dogs: Effects on the Somatossensory Evoked Potential, Intracranial Pressure, and Blood-Brain Barrier

摘要

Medical personnel routinely recommend placing the victim of dysbaric or nosocomial cerebral air embolism in the Trendelenburg position. This maneuver is expected to reduce the chance of subsequent cerebral air emboli and to hasten clearance of bubbles trapped in the cerebral circulation. The Trendelenburg position will also increase intracranial pressure and reduce cerebral perfusion pressure; this may have an adverse effect on recovery of the injured brain. We placed 8 dogs in the left lateral decubitus, 45 deg. Trendelenburg position for 1 h following cerebral air embolism and transient hypertension, then treated the animals with compression on a modified U.S. Navy Treatment Table 6A (head-down or HD group). We compared somatosensory evoked potentials (SSEP), intracranial pressure and pressure-volume index(PVI), brain water , and blood-brain barrier function assessed by extravasation of Evans Blue to these variables in 9 embolized and hypertensive dogs maintained in a head-up (sphinx) position as controls (horizontal or HZ group).