title: Delayed intracranial hemorrhage in the anticoagulated patient: A systematic review.
abstract: BACKGROUND
  A significant population of elderly Americans on warfarin is at risk for immediate and delayed intracranial hemorrhage. This qualitative systematic review ascertains the delayed intracranial hemorrhage risk associated with minor head injury and preinjury warfarin use.
  
  
  METHODS
  A systematic review using MEDLINE, EMBASE, and the Cochrane Library was performed in August 2014. Cohort studies evaluating delayed intracranial hemorrhage in patients with minor head injuries on warfarin were eligible for inclusion. The definition of delayed hemorrhage was any intracranial bleeding detected subsequent to initial negative brain imaging result following the head injury. Three authors screened and abstracted the data and evaluated methodological quality. Data abstraction also included clinical characteristics that could identify risk factors for delayed intracranial hemorrhage.
  
  
  RESULTS
  The search retrieved 294 unique articles, of which 5 studies constituted the final review. The studies included data on 1,257 patients. Among higher-quality studies, the incidence of delayed intracranial hemorrhage ranged from 5.8 to 72 per 1,000 cases of patients on warfarin with minor head injury. Population age was an influential factor in this range of incident rates. International normalized ratio levels had no clear association with individual risk for delayed intracranial hemorrhage.
  
  
  CONCLUSIONS
  The incidence of delayed intracranial hemorrhage is low among patients on warfarin with minor head injury. Trauma centers should consider the characteristics of the population they serve compared with the published studies when determining management strategies for these patients.
  
  
  METHODS
  Systematic review, level III.
authors.affiliation: From the Department of Emergency Medicine (J.M., B.N., G.H., J.G.-G.), Department of Surgery (J.W.), Inova Fairfax Hospital, Falls Church, VA, Henry Ford Hospital; School of Medicine (L.L.), Wayne State University, Detroit, Michigan; Department of Emergency Medicine (A.L.), MetroHealth, Cleveland, Ohio; and Department of Emergency Medicine (S.N.), Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Joseph
authors.initials: J
authors.lastname: Miller
authors.forename: Leedor
authors.initials: L
authors.lastname: Lieberman
authors.forename: Bashar
authors.initials: B
authors.lastname: Nahab
authors.forename: Gina
authors.initials: G
authors.lastname: Hurst
authors.forename: Jayna
authors.initials: J
authors.lastname: Gardner-Gray
authors.forename: Aaron
authors.initials: A
authors.lastname: Lewandowski
authors.forename: Shaw
authors.initials: S
authors.lastname: Natsui
authors.forename: Jill
authors.initials: J
authors.lastname: Watras
mesh_terms: D000925:Anticoagulants / Q000009:adverse effects*; D006259:Craniocerebral Trauma / Q000150:complications*; D006801:Humans; D015994:Incidence; D020300:Intracranial Hemorrhages / Q000139:chemically induced / Q000453:epidemiology / Q000209:etiology*; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014859:Warfarin / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D014859:Warfarin