Utility of Repeat Head CT in Patients on Preinjury Antithrombotic Medications.

Presently, there are no standardized guidelines regarding the necessity or timing of repeat head imaging in patients on antithrombotics (antiplatelet agents, warfarin, or novel oral anticoagulants) with suspected traumatic brain injury. This is a two-year single institutional retrospective analysis of patients with suspected traumatic brain injury on antithrombotic medications. Patients with a stable or negative repeat head CT were compared with patients who developed a new bleed or demonstrated progression of intracranial hemorrhage (ICH). Of 110 patients, 55 patients (50%) had a positive initial CT, two patients (1.8%) developed a new bleed after initially normal head CT, and 21 patients (19.1%) demonstrated worsening ICH. Patients with worsening or delayed ICH had a higher median Injury Severity Score (14 5, < 0.001), higher head/neck and face Abbreviated Injury Severity scores (both < 0.05), and were more likely to be receiving combination therapy with warfarin and clopidogrel (4.3% 0%, = 0.05). On multivariate analysis, lower face and head/neck Abbreviated Injury Severity scores were associated with a decreased risk for delayed or worsening hemorrhage (odds ratio = 0.21 and 0.46, respectively, < 0.05). Repeat head CT in patients on a preinjury antithrombotic has a low yield. The use of combination therapy may result in an increased risk for delayed hemorrhage or hemorrhage progression.