title: Outcomes of warfarinized patients with minor head injury and normal initial CT scan.
abstract: OBJECTIVE
  We investigated delayed outcomes of patients with minor head injury, warfarin, and a normal initial head computer tomographic (CT) scan finding.
  
  
  METHODS
  We conducted a single-center, retrospective study on such patients who were admitted. A second CT was not mandatory. International normalized ratios were classified into subtherapeutic, therapeutic, and supratherapeutic ranges. We traced them 2 weeks after discharge for delayed intracranial hemorrhage (ICH). Primary outcomes were proportions with ICH on second CT, fresh-frozen plasma (FFP) and/or vitamin K administration, and neurosurgical intervention. Secondary outcomes were hospital length of stay and the proportion with ICH 2 weeks after discharge. We explored differences in proportions of ICH during hospital stay among different strata (age ≥65 years, antiplatelet therapy, supratherapeutic international normalized ratio ranges, and FFP administration). Data were analyzed using descriptive statistics. P values less than .05 were considered statistically significant.
  
  
  RESULTS
  We recruited 298 patients. Of admissions (N = 295), 11 (3.7%) had a second CT, with one (0.3%) abnormality. There were 7 (2.4%) and 8 (2.7%) patients who received FFP and vitamin K, respectively. One patient (0.3%) required neurosurgical intervention. The median hospital length of stay was 3 (interquartile range, 2) days. No patients reattended 2 weeks after discharge. There were no statistically significant differences in the proportions of ICH during hospital stay among the 4 strata.
  
  
  CONCLUSIONS
  Delayed ICH was rare with no predictive factors. Clinical monitoring before deciding on second CT was safe. The optimal period and mode of observation had yet to be determined.
authors.affiliation: Emergency Department, Jurong Health Services, Singapore. Electronic address: Beng_Leong_Lim@Juronghealth.com.sg.
authors.forename: Beng Leong
authors.initials: BL
authors.lastname: Lim
authors.affiliation: Emergency Department, Tan Tock Seng Hospital, Singapore. Electronic address: charmaine_manauis@Ttsh.com.sg.
authors.forename: Charmaine
authors.initials: C
authors.lastname: Manauis
authors.affiliation: Emergency Department, Jurong Health Services, Singapore. Electronic address: Marxengel_L_Asinas@Juronghealth.com.sg.
authors.forename: Marxengel L
authors.initials: ML
authors.lastname: Asinas-Tan
mesh_terms: D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects*; D006259:Craniocerebral Trauma / Q000150:complications* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D020300:Intracranial Hemorrhages / Q000000981:diagnostic imaging / Q000209:etiology*; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014859:Warfarin / Q000009:adverse effects*
chemical_list: D000925:Anticoagulants; D014859:Warfarin