title: Prognostic significance of blood-brain barrier disruption in patients with severe nonpenetrating traumatic brain injury requiring decompressive craniectomy.
abstract: OBJECTIVE
  The authors assessed the risk factors and outcomes associated with blood-brain barrier (BBB) disruption in patients with severe, nonpenetrating, traumatic brain injury (TBI) requiring decompressive craniectomy.
  
  
  METHODS
  At 2 major neurotrauma centers in Western Australia, a retrospective cohort study was conducted among 97 adult neurotrauma patients who required an external ventricular drain (EVD) and decompressive craniectomy during 2004-2012. Glasgow Outcome Scale scores were used to assess neurological outcomes. Logistic regression was used to identify factors associated with BBB disruption, defined by a ratio of total CSF protein concentrations to total plasma protein concentration > 0.007 in the earliest CSF specimen collected after TBI.
  
  
  RESULTS
  Of the 252 patients who required decompressive craniectomy, 97 (39%) required an EVD to control intracranial pressure, and biochemical evidence of BBB disruption was observed in 43 (44%). Presence of disruption was associated with more severe TBI (median predicted risk for unfavorable outcome 75% vs 63%, respectively; p = 0.001) and with worse outcomes at 6, 12, and 18 months than was absence of BBB disruption (72% vs 37% unfavorable outcomes, respectively; p = 0.015). The only risk factor significantly associated with increased risk for BBB disruption was presence of nonevacuated intracerebral hematoma (> 1 cm diameter) (OR 3.03, 95% CI 1.23-7.50; p = 0.016). Although BBB disruption was associated with more severe TBI and worse long-term outcomes, when combined with the prognostic information contained in the Corticosteroid Randomization after Significant Head Injury (CRASH) prognostic model, it did not seem to add significant prognostic value (area under the receiver operating characteristic curve 0.855 vs 0.864, respectively; p = 0.453).
  
  
  CONCLUSIONS
  Biochemical evidence of BBB disruption after severe nonpenetrating TBI was common, especially among patients with large intracerebral hematomas. Disruption of the BBB was associated with more severe TBI and worse long-term outcomes, but when combined with the prognostic information contained in the CRASH prognostic model, this information did not add significant prognostic value.
authors.affiliation: Department of Intensive Care Medicine, Royal Perth Hospital;
authors.forename: Kwok M
authors.initials: KM
authors.lastname: Ho
authors.forename: Stephen
authors.initials: S
authors.lastname: Honeybul
authors.forename: Cheng B
authors.initials: CB
authors.lastname: Yip
authors.forename: Benjamin I
authors.initials: BI
authors.lastname: Silbert
mesh_terms: D000328:Adult; D001315:Australia; D001812:Blood-Brain Barrier / Q000503:physiopathology*; D001930:Brain Injuries / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D015331:Cohort Studies; D056424:Decompressive Craniectomy; D005260:Female; D023261:Glasgow Outcome Scale; D006801:Humans; D016015:Logistic Models; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
keywords: BBB = blood-brain barrier; CRASH = Corticosteroid Randomization after Significant Head Injury; EVD = external ventricular drain; ICP = intracranial pressure; ROC = receiver operating characteristic; TBI = traumatic brain injury; outcome; prediction; prognosis; traumatic brain injury