Secondary intracranial hemorrhage after mild head injury in patients with low-dose acetylsalicylate acid prophylaxis.

BACKGROUND: Low-dose acetylsalicylate acid (LDA) therapy is accepted as a major risk factor for intracranial hemorrhages (ICH) in head injuries. Coincidentally, patient admissions that might be indicated for in hospital observation of neurologic function causes increased health care costs. In the literature, there is no evidence concerning the incidence of secondary intracranial hemorrhagic events (SIHE) in patients with LDA prophylaxis that had negative primary computed tomography (CT)-scan of the head.
METHODS: In this prospective study, we enrolled 100 consecutive trauma patients older than 65 years presenting in a Level I urban trauma center after a mild head injury (Glasgow Coma Scale score of 15) who had LDA prophylaxis. Patients included had a negative primary head CT-scan concerning ICH. For analysis of the incidence of SIHEs patients had routine repeat head CT (RRHCT) after 12 hours to 24 hours.
RESULTS: Sixty-one patients were women and 39 men. Mean age was 81 years +/- 10 years. Injury mechanism was a level fall in 84 cases and others in 16. In four patients (4%) an SIHE was detected in the RRHCT (p < 0.00001). In two patients (2%) major secondary ICH had occurred without neurologic deterioration at the time of RRHCT with fatal outcome in one patient and neurosurgical intervention in another. The remaining two patients (2%) had minor SIHE with an uneventful clinical course.
CONCLUSION: The incidence of SIHE has been neglected until now. The current study revealed that patients with LDA prophylaxis after mild head injury with negative primary head CT should be subjected to RRHCT within 12 hours to 24 hours to accurately identify SIHE. Alternatively to RRHCT, patients should be subjected to a prolonged in-hospital observation for at least 48 hours.