title: Beta-blocker exposure is associated with improved survival after severe traumatic brain injury.
abstract: BACKGROUND
  Beta-blocker use in elective noncardiac surgery has been associated with a reduction in mortality and cardiovascular complications. Traumatic brain injury (TBI) is often associated with a hyperadrenergic state. We hypothesized that adrenergic blockade would confer improved survival among TBI patients.
  
  
  METHODS
  Retrospective review of the Trauma Registry of the American College of Surgeons database at a Level I trauma center was conducted. All trauma patients admitted from January 2004 to March 2005 with head Abbreviated Injury Scale score of 3 or greater were evaluated. Patients with length of stay <4 or >30 days were excluded. Beta-blocker exposure was defined as receiving beta-blockers for 2 or more consecutive days.
  
  
  RESULTS
  In all, 420 patients met inclusion criteria: 174 patients exposed to beta-blockers [BB(+)] and 246 not exposed [BB(-)]. Mean age in BB(+) group was 50 years and 36 years in BB(-) group (p < 0.001). Mean Injury Severity Score was 33.6 for BB(+) group and 30.8 for BB(-) group (p = 0.01). Predicted survival (by Trauma and Injury Severity Score) for BB(+) group was 59.1% compared with 70.3% for BB(-) group (p < 0.001). Observed mortality for BB(+) group was 5.1%, 10.8% for BB(-) group (p = 0.036). Adjusted incidence rate ratio of mortality among those exposed to beta-blockers compared with those not exposed was 0.29 (95% confidence interval).
  
  
  CONCLUSIONS
  Beta-blocker exposure was associated with a significant reduction in mortality in patients with severe TBI. This reduction in mortality is even more impressive, considering that the BB(+) group was older, more severely injured, and had lower predicted survival.
authors.affiliation: Departments of Surgery, Vanderbilt University Medical Center, Nashville, TN 37212, USA. bryan.cotton@vanderbilt.edu
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Cotton
authors.forename: Kimberly B
authors.initials: KB
authors.lastname: Snodgrass
authors.forename: Sloan B
authors.initials: SB
authors.lastname: Fleming
authors.forename: Robert O
authors.initials: RO
authors.lastname: Carpenter
authors.forename: Clinton D
authors.initials: CD
authors.lastname: Kemp
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Arbogast
authors.forename: John A
authors.initials: JA
authors.lastname: Morris
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D001930:Brain Injuries / Q000188:drug therapy* / Q000401:mortality* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D019990:Perioperative Care; D012044:Regression Analysis; D012189:Retrospective Studies; D012306:Risk; D015144:Southeastern United States / Q000453:epidemiology; D016896:Treatment Outcome
chemical_list: D000319:Adrenergic beta-Antagonists