Mild Traumatic Brain Injury in Patients on Long-Term Anticoagulation Therapy: Do They Really Need Repeated Head CT Scan?

Abstract

Background: Mild traumatic brain injury (mTBI), defined as blunt trauma to the head resulting in witnessed loss of consciousness, definite amnesia, or witnessed disorientation with a Glasgow Coma Scale (GCS) score of 14 or 15 is a common occurrence in the emergency department. In mTBI, oral anticoagulation is known to be an important risk factor for hemorrhage. Clinical guidelines recommend baseline computed tomographic (CT) scan and observation for 24 hours plus a CT scan before discharge.

Methods: We compared the non-anticoagulated and anticoagulated patients presenting at our emergency department with mTBI and no neurologic signs (GCS = 15). Every non-anticoagulated patient underwent only a baseline CT scan, whereas the anticoagulated group underwent a second CT scan after a 24-hour observation period.

Results: Between April 2012 and April 2013, we observed 908 adult patients with mTBI and a GCS score of 15; 74 patients (8.1%) were taking oral anticoagulant drugs as long-term therapy, whereas the remaining 834 patients (91.9%) were not. In the non-anticoagulation group, 38 patients (4.6%) were positive for hemorrhage. Two patients underwent neurosurgical intervention. In the anticoagulation group, 5 patients (6.8%) were positive for hemorrhage. No patient underwent neurosurgical intervention. None of them died. The differences between the two groups were not statistically significant.

Conclusions: Patients with a GCS score of 15 who are taking long-term anticoagulation therapy and who present with mTBI have a risk of cranial hemorrhage that is likely to be similar to that of non-anticoagulated patients. It may be reasonable to envision a protocol including only one CT scan and an appropriate observation period.

Keywords: Anticoagulants; GCS 15; Head CT scan; Mild traumatic brain injury; Minor head trauma.