title: Further investigations into the speed of cerebral swelling following blunt cranial trauma.
abstract: An anesthetized sheep model of traumatic brain injury (TBI) has been developed to assess early changes in intracranial pressure (ICP) following closed head injury. Immediately after TBI, a transient (<10 min) hypertensive response occurred, followed by significant and prolonged systemic hypotension. ICP demonstrated a biphasic response, being seven times baseline values of 8 ± 2 mm Hg 10 min after injury, decreasing to 25 ± 2 mm Hg by 30 min, and then increasing to values exceeding 30 mm Hg by 4 h postinjury. ICP was always significantly higher than baseline values, which combined with hypotension, reduced cerebral perfusion pressure to less than 60% of normal. This early and sustained increase in ICP after craniocerebral trauma acutely alters cerebral perfusion pressure and brain oxygenation and provides a potential pathophysiological explanation for immediate clinical manifestations in humans following significant TBI.
authors.affiliation: Adelaide Centre for Neuroscience Research, School of Medical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia. roger.byard@adelaide.edu.au
authors.forename: Roger W
authors.initials: RW
authors.lastname: Byard
authors.forename: Levon
authors.initials: L
authors.lastname: Gabrielian
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Helps
authors.forename: Emma
authors.initials: E
authors.lastname: Thornton
authors.forename: Robert
authors.initials: R
authors.lastname: Vink
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000098:blood supply; D001929:Brain Edema / Q000473:pathology*; D049429:Forensic Pathology; D016489:Head Injuries, Closed / Q000473:pathology*; D006973:Hypertension / Q000473:pathology; D007022:Hypotension / Q000473:pathology; D019586:Intracranial Hypertension / Q000473:pathology; D008297:Male; D023421:Models, Animal; D012756:Sheep; D013997:Time Factors