Effect of Different Surgical Positions on the Cerebral Venous Drainage: an Ultrasound Study on Healthy Volunteers

The different positions used in neurosurgery (park bench, prone) for better accessibility to the operating field can impact on the cerebral venous drainage due to the effects of internal jugular venous outflow of blood and may increase intracranial pressure. The kinking of the internal jugular vein due to excessive neck flexion and rotation in park bench or flexion in the prone position may lead to kinking or twisting of the vein. This has been hypothesized as the major cause of disturbed venous drainage during surgery and in postoperative patients may lead to neck swelling, brachial plexus injury, macroglossia (swollen tongue), delayed airway obstruction and increases in intracranial pressure.

Optimal brain perfusion is best in the neutral position of the head, but surgery cannot always be performed with this. Thus, we look to measure the internal jugular venous flow at different positions as there have been little studies looking at this important contributing factor.