Pressure gradients within the central nervous system

The existence of clinically relevant pressure gradients within the central nervous system (CNS) is the subject of ongoing debate. Such gradients, ii t hey do exist, would have significant implications for intracranial pressure (ICP) monitoring and ICP management in traumatic brain injury. As summaris ed in this short review, there is considerable experimental and clinical ev idence that ICP is not evenly distributed within the central nervous system . Larger clinical trials on the implications of ICP gradients are warranted to address questions on the correct placement of ICP probes and on ICP man agement. It seems paradoxical to develop and employ ever more sophisticated monitoring devices in traumatic brain injury, such as monitoring of CNS me tabolites with microdialysis or near-infrared spectroscopy, while fundament al issues such as the existence of ICP gradients remain unresolved. (C) 199 9 Harcourt Publishers Ltd.