Is there an upper limit of intracranial pressure in patients with severe head injury if cerebral perfusion pressure is maintained?

Abstract
Authors of recent studies have championed the importance of maintaining cerebral perfusion pressure (CPP) to prevent secondary brain injury following traumatic head injury. Data from these studies have provided little information regarding outcome following severe head injury in patients with an intracranial pressure (ICP) greater than 40 mm Hg, however, in July 1997 the authors instituted a protocol for the management of severe head injury in patients with a Glasgow Coma Scale score lower than 9. The protocol was focused on resuscitation from acidosis, maintenance of a CPP greater than 60 mm Hg through whatever means necessary as well as elevation of the head of the bed, mannitol infusion, and ventriculostomy with cerebrospinal fluid drainage for control of ICP. Since the institution of this protocol, nine patients had a sustained ICP greater than 40 mm Hg for 2 or more hours, and five of these had an ICP greater than 75 mm Hg on insertion of the ICP monitor and later experienced herniation and expired w...