title: Biochemical markers of cerebral injury in patients with minor head trauma and ethanol intoxication.
abstract: OBJECTIVE
  To determine whether biochemical markers can selectively identify those intoxicated patients with presumed minor head injuries who are likely to have CT evidence of intracranial injury.
  
  
  METHODS
  Patients presenting to the ED with simultaneous presumed minor head trauma and ethanol intoxication were prospectively entered into this cross-sectional study. Following phlebotomy, all patients received cranial CT. Associations between the presence of an abnormal CT scan for injury and serum levels of the following biochemical markers were sought: serum catecholamines, creatine kinase-brain band (CK-BB), and serum amylase. Serum levels are reported as mean +/- SEM.
  
  
  RESULTS
  Nine of the 107 patients (8.4%; 95% CI 3.9-15.4%) had evidence of intracranial injury on CT. Mean serum CK-BB (16.1 +/- 3.7 vs 13.2 +/- 9.6 ng/mL), serum norepinephrine (913 +/- 117 vs 1,089 +/- 76 pg/mL), and serum amylase (64.9 +/- 14.8 vs 84 +/- 4.7 U/L) levels were not significantly different in patients with and without CT evidence of intracranial injury, respectively. Mean serum epinephrine (298 +/- 54 vs 167 +/- 18 pg/mL; p = 0.03) and serum dopamine (218 +/- 50 vs 130 +/- 9 pg/mL; p = 0.014) levels were significantly elevated in the group with intracranial injury on CT. A threshold level of serum dopamine > or = 140 pg/mL yields a sensitivity of 89% (95% CI 52-100%) and a specificity of 80% (95% CI 70-87%) for CT-evident injury. A threshold level of serum epinephrine > or = 218 pg/mL yields a sensitivity of 89% (95% CI 52-100%) and a specificity of 80% (95% CI 70-87%) for CT-evident injury.
  
  
  CONCLUSIONS
  Elevated serum epinephrine and dopamine levels are associated with intracranial CT-evident injury for ethanol-intoxicated patients with presumed minor head injuries. The potential use of these biochemical markers to guide a more selective approach to cranial CT scanning warrants further evaluation.
authors.affiliation: Highland General Hospital, Oakland, CA, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Levitt
authors.forename: L A
authors.initials: LA
authors.lastname: Cook
authors.forename: B C
authors.initials: BC
authors.lastname: Simon
authors.forename: V
authors.initials: V
authors.lastname: Williams
mesh_terms: D000435:Alcoholic Intoxication / Q000097:blood / Q000150:complications*; D000681:Amylases / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001930:Brain Injuries / Q000097:blood* / Q000000981:diagnostic imaging / Q000209:etiology; D002395:Catecholamines / Q000097:blood*; D003402:Creatine Kinase / Q000097:blood*; D003430:Cross-Sectional Studies; D000431:Ethanol / Q000506:poisoning*; D006801:Humans; D007527:Isoenzymes; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D015415:Biomarkers; D002395:Catecholamines; D007527:Isoenzymes; D000431:Ethanol; D003402:Creatine Kinase; D000681:Amylases