Delayed intracranial hemorrhage in the anticoagulated patient: A systematic review.

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.

CONCLUSION: 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.

LEVEL OF EVIDENCE: Systematic review, level III.