title: Management of minor head injury in patients receiving oral anticoagulant therapy: a prospective study of a 24-hour observation protocol.
abstract: OBJECTIVE
  Patients receiving warfarin who experience minor head injury are at risk of intracranial hemorrhage, and optimal management after a single head computed tomography (CT) scan is unclear. We evaluate a protocol of 24-hour observation followed by a second head CT scan.
  
  
  METHODS
  In this prospective case series, we enrolled consecutive patients receiving warfarin and showing no intracranial lesions on a first CT scan after minor head injury treated at a Level II trauma center. We implemented a structured clinical pathway, including 24-hour observation and a CT scan performed before discharge. We then evaluated the frequency of death, admission, neurosurgery, and delayed intracranial hemorrhage.
  
  
  RESULTS
  We enrolled and observed 97 consecutive patients. Ten refused the second CT scan and were well during 30-day follow-up. Repeated CT scanning in the remaining 87 patients revealed a new hemorrhage lesion in 5 (6%), with 3 subsequently hospitalized and 1 receiving craniotomy. Two patients discharged after completing the study protocol with 2 negative CT scan results were admitted 2 and 8 days later with symptomatic subdural hematomas; neither received surgery. Two of the 5 patients with delayed bleeding at 24 hours had an initial international normalized ratio greater than 3.0, as did both patients with delayed bleeding beyond 24 hours. The relative risk of delayed hemorrhage with an initial international normalized ratio greater than 3.0 was 14 (95% confidence interval 4 to 49).
  
  
  CONCLUSIONS
  For patients receiving warfarin who experience minor head injury and have a negative initial head CT scan result, a protocol of 24-hour observation followed by a second CT scan will identify most occurrences of delayed bleeding. An initial international normalized ratio greater than 3 suggests higher risk.
authors.affiliation: Emergency Department, Ospedali Riuniti di Ancona, Ancona, Italy. vincenzomenditto74@yahoo.it
authors.forename: Vincenzo G
authors.initials: VG
authors.lastname: Menditto
authors.forename: Moira
authors.initials: M
authors.lastname: Lucci
authors.forename: Stefano
authors.initials: S
authors.lastname: Polonara
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pomponio
authors.forename: Armando
authors.initials: A
authors.lastname: Gabrielli
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects*; D006259:Craniocerebral Trauma / Q000150:complications / Q000000981:diagnostic imaging / Q000628:therapy*; D019091:Critical Pathways; D005260:Female; D006801:Humans; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014193:Trauma Centers; D014859:Warfarin / Q000009:adverse effects*; D057832:Watchful Waiting
chemical_list: D000925:Anticoagulants; D014859:Warfarin